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LeafOS / LeafOS-Project / android_art / 00cca3a275562d110a8b35094b9b12fac37f67ab / . / compiler / optimizing / code_generator_arm_vixl.cc
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/*
* Copyright (C) 2016 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include "code_generator_arm_vixl.h"
#include "arch/arm/asm_support_arm.h"
#include "arch/arm/instruction_set_features_arm.h"
#include "art_method.h"
#include "base/bit_utils.h"
#include "base/bit_utils_iterator.h"
#include "code_generator_utils.h"
#include "common_arm.h"
#include "compiled_method.h"
#include "entrypoints/quick/quick_entrypoints.h"
#include "gc/accounting/card_table.h"
#include "intrinsics_arm_vixl.h"
#include "linker/arm/relative_patcher_thumb2.h"
#include "mirror/array-inl.h"
#include "mirror/class-inl.h"
#include "thread.h"
#include "utils/arm/assembler_arm_vixl.h"
#include "utils/arm/managed_register_arm.h"
#include "utils/assembler.h"
#include "utils/stack_checks.h"
namespace art {
namespace arm {
namespace vixl32 = vixl::aarch32;
using namespace vixl32; // NOLINT(build/namespaces)
using helpers::DRegisterFrom;
using helpers::DWARFReg;
using helpers::HighDRegisterFrom;
using helpers::HighRegisterFrom;
using helpers::InputDRegisterAt;
using helpers::InputOperandAt;
using helpers::InputRegister;
using helpers::InputRegisterAt;
using helpers::InputSRegisterAt;
using helpers::InputVRegister;
using helpers::InputVRegisterAt;
using helpers::Int32ConstantFrom;
using helpers::Int64ConstantFrom;
using helpers::LocationFrom;
using helpers::LowRegisterFrom;
using helpers::LowSRegisterFrom;
using helpers::OperandFrom;
using helpers::OutputRegister;
using helpers::OutputSRegister;
using helpers::OutputVRegister;
using helpers::RegisterFrom;
using helpers::SRegisterFrom;
using helpers::Uint64ConstantFrom;
using vixl::ExactAssemblyScope;
using vixl::CodeBufferCheckScope;
using RegisterList = vixl32::RegisterList;
static bool ExpectedPairLayout(Location location) {
// We expected this for both core and fpu register pairs.
return ((location.low() & 1) == 0) && (location.low() + 1 == location.high());
}
// Use a local definition to prevent copying mistakes.
static constexpr size_t kArmWordSize = static_cast<size_t>(kArmPointerSize);
static constexpr size_t kArmBitsPerWord = kArmWordSize * kBitsPerByte;
static constexpr uint32_t kPackedSwitchCompareJumpThreshold = 7;
// Reference load (except object array loads) is using LDR Rt, [Rn, #offset] which can handle
// offset < 4KiB. For offsets >= 4KiB, the load shall be emitted as two or more instructions.
// For the Baker read barrier implementation using link-generated thunks we need to split
// the offset explicitly.
constexpr uint32_t kReferenceLoadMinFarOffset = 4 * KB;
// Flags controlling the use of link-time generated thunks for Baker read barriers.
constexpr bool kBakerReadBarrierLinkTimeThunksEnableForFields = true;
constexpr bool kBakerReadBarrierLinkTimeThunksEnableForArrays = true;
constexpr bool kBakerReadBarrierLinkTimeThunksEnableForGcRoots = true;
// The reserved entrypoint register for link-time generated thunks.
const vixl32::Register kBakerCcEntrypointRegister = r4;
#ifdef __
#error "ARM Codegen VIXL macro-assembler macro already defined."
#endif
// NOLINT on __ macro to suppress wrong warning/fix (misc-macro-parentheses) from clang-tidy.
#define __ down_cast<CodeGeneratorARMVIXL*>(codegen)->GetVIXLAssembler()-> // NOLINT
#define QUICK_ENTRY_POINT(x) QUICK_ENTRYPOINT_OFFSET(kArmPointerSize, x).Int32Value()
// Marker that code is yet to be, and must, be implemented.
#define TODO_VIXL32(level) LOG(level) << __PRETTY_FUNCTION__ << " unimplemented "
static inline void ExcludeIPAndBakerCcEntrypointRegister(UseScratchRegisterScope* temps,
HInstruction* instruction) {
DCHECK(temps->IsAvailable(ip));
temps->Exclude(ip);
DCHECK(!temps->IsAvailable(kBakerCcEntrypointRegister));
DCHECK_EQ(kBakerCcEntrypointRegister.GetCode(),
linker::Thumb2RelativePatcher::kBakerCcEntrypointRegister);
DCHECK_NE(instruction->GetLocations()->GetTempCount(), 0u);
DCHECK(RegisterFrom(instruction->GetLocations()->GetTemp(
instruction->GetLocations()->GetTempCount() - 1u)).Is(kBakerCcEntrypointRegister));
}
static inline void EmitPlaceholderBne(CodeGeneratorARMVIXL* codegen, vixl32::Label* patch_label) {
ExactAssemblyScope eas(codegen->GetVIXLAssembler(), kMaxInstructionSizeInBytes);
__ bind(patch_label);
vixl32::Label placeholder_label;
__ b(ne, EncodingSize(Wide), &placeholder_label); // Placeholder, patched at link-time.
__ bind(&placeholder_label);
}
static inline bool CanEmitNarrowLdr(vixl32::Register rt, vixl32::Register rn, uint32_t offset) {
return rt.IsLow() && rn.IsLow() && offset < 32u;
}
class EmitAdrCode {
public:
EmitAdrCode(ArmVIXLMacroAssembler* assembler, vixl32::Register rd, vixl32::Label* label)
: assembler_(assembler), rd_(rd), label_(label) {
ExactAssemblyScope aas(assembler, kMaxInstructionSizeInBytes);
adr_location_ = assembler->GetCursorOffset();
assembler->adr(EncodingSize(Wide), rd, label);
}
~EmitAdrCode() {
DCHECK(label_->IsBound());
// The ADR emitted by the assembler does not set the Thumb mode bit we need.
// TODO: Maybe extend VIXL to allow ADR for return address?
uint8_t* raw_adr = assembler_->GetBuffer()->GetOffsetAddress<uint8_t*>(adr_location_);
// Expecting ADR encoding T3 with `(offset & 1) == 0`.
DCHECK_EQ(raw_adr[1] & 0xfbu, 0xf2u); // Check bits 24-31, except 26.
DCHECK_EQ(raw_adr[0] & 0xffu, 0x0fu); // Check bits 16-23.
DCHECK_EQ(raw_adr[3] & 0x8fu, rd_.GetCode()); // Check bits 8-11 and 15.
DCHECK_EQ(raw_adr[2] & 0x01u, 0x00u); // Check bit 0, i.e. the `offset & 1`.
// Add the Thumb mode bit.
raw_adr[2] |= 0x01u;
}
private:
ArmVIXLMacroAssembler* const assembler_;
vixl32::Register rd_;
vixl32::Label* const label_;
int32_t adr_location_;
};
// SaveLiveRegisters and RestoreLiveRegisters from SlowPathCodeARM operate on sets of S registers,
// for each live D registers they treat two corresponding S registers as live ones.
//
// Two following functions (SaveContiguousSRegisterList, RestoreContiguousSRegisterList) build
// from a list of contiguous S registers a list of contiguous D registers (processing first/last
// S registers corner cases) and save/restore this new list treating them as D registers.
// - decreasing code size
// - avoiding hazards on Cortex-A57, when a pair of S registers for an actual live D register is
// restored and then used in regular non SlowPath code as D register.
//
// For the following example (v means the S register is live):
// D names: | D0 | D1 | D2 | D4 | ...
// S names: | S0 | S1 | S2 | S3 | S4 | S5 | S6 | S7 | ...
// Live? | | v | v | v | v | v | v | | ...
//
// S1 and S6 will be saved/restored independently; D registers list (D1, D2) will be processed
// as D registers.
//
// TODO(VIXL): All this code should be unnecessary once the VIXL AArch32 backend provides helpers
// for lists of floating-point registers.
static size_t SaveContiguousSRegisterList(size_t first,
size_t last,
CodeGenerator* codegen,
size_t stack_offset) {
static_assert(kSRegSizeInBytes == kArmWordSize, "Broken assumption on reg/word sizes.");
static_assert(kDRegSizeInBytes == 2 * kArmWordSize, "Broken assumption on reg/word sizes.");
DCHECK_LE(first, last);
if ((first == last) && (first == 0)) {
__ Vstr(vixl32::SRegister(first), MemOperand(sp, stack_offset));
return stack_offset + kSRegSizeInBytes;
}
if (first % 2 == 1) {
__ Vstr(vixl32::SRegister(first++), MemOperand(sp, stack_offset));
stack_offset += kSRegSizeInBytes;
}
bool save_last = false;
if (last % 2 == 0) {
save_last = true;
--last;
}
if (first < last) {
vixl32::DRegister d_reg = vixl32::DRegister(first / 2);
DCHECK_EQ((last - first + 1) % 2, 0u);
size_t number_of_d_regs = (last - first + 1) / 2;
if (number_of_d_regs == 1) {
__ Vstr(d_reg, MemOperand(sp, stack_offset));
} else if (number_of_d_regs > 1) {
UseScratchRegisterScope temps(down_cast<CodeGeneratorARMVIXL*>(codegen)->GetVIXLAssembler());
vixl32::Register base = sp;
if (stack_offset != 0) {
base = temps.Acquire();
__ Add(base, sp, Operand::From(stack_offset));
}
__ Vstm(F64, base, NO_WRITE_BACK, DRegisterList(d_reg, number_of_d_regs));
}
stack_offset += number_of_d_regs * kDRegSizeInBytes;
}
if (save_last) {
__ Vstr(vixl32::SRegister(last + 1), MemOperand(sp, stack_offset));
stack_offset += kSRegSizeInBytes;
}
return stack_offset;
}
static size_t RestoreContiguousSRegisterList(size_t first,
size_t last,
CodeGenerator* codegen,
size_t stack_offset) {
static_assert(kSRegSizeInBytes == kArmWordSize, "Broken assumption on reg/word sizes.");
static_assert(kDRegSizeInBytes == 2 * kArmWordSize, "Broken assumption on reg/word sizes.");
DCHECK_LE(first, last);
if ((first == last) && (first == 0)) {
__ Vldr(vixl32::SRegister(first), MemOperand(sp, stack_offset));
return stack_offset + kSRegSizeInBytes;
}
if (first % 2 == 1) {
__ Vldr(vixl32::SRegister(first++), MemOperand(sp, stack_offset));
stack_offset += kSRegSizeInBytes;
}
bool restore_last = false;
if (last % 2 == 0) {
restore_last = true;
--last;
}
if (first < last) {
vixl32::DRegister d_reg = vixl32::DRegister(first / 2);
DCHECK_EQ((last - first + 1) % 2, 0u);
size_t number_of_d_regs = (last - first + 1) / 2;
if (number_of_d_regs == 1) {
__ Vldr(d_reg, MemOperand(sp, stack_offset));
} else if (number_of_d_regs > 1) {
UseScratchRegisterScope temps(down_cast<CodeGeneratorARMVIXL*>(codegen)->GetVIXLAssembler());
vixl32::Register base = sp;
if (stack_offset != 0) {
base = temps.Acquire();
__ Add(base, sp, Operand::From(stack_offset));
}
__ Vldm(F64, base, NO_WRITE_BACK, DRegisterList(d_reg, number_of_d_regs));
}
stack_offset += number_of_d_regs * kDRegSizeInBytes;
}
if (restore_last) {
__ Vldr(vixl32::SRegister(last + 1), MemOperand(sp, stack_offset));
stack_offset += kSRegSizeInBytes;
}
return stack_offset;
}
void SlowPathCodeARMVIXL::SaveLiveRegisters(CodeGenerator* codegen, LocationSummary* locations) {
size_t stack_offset = codegen->GetFirstRegisterSlotInSlowPath();
size_t orig_offset = stack_offset;
const uint32_t core_spills = codegen->GetSlowPathSpills(locations, /* core_registers */ true);
for (uint32_t i : LowToHighBits(core_spills)) {
// If the register holds an object, update the stack mask.
if (locations->RegisterContainsObject(i)) {
locations->SetStackBit(stack_offset / kVRegSize);
}
DCHECK_LT(stack_offset, codegen->GetFrameSize() - codegen->FrameEntrySpillSize());
DCHECK_LT(i, kMaximumNumberOfExpectedRegisters);
saved_core_stack_offsets_[i] = stack_offset;
stack_offset += kArmWordSize;
}
CodeGeneratorARMVIXL* arm_codegen = down_cast<CodeGeneratorARMVIXL*>(codegen);
arm_codegen->GetAssembler()->StoreRegisterList(core_spills, orig_offset);
uint32_t fp_spills = codegen->GetSlowPathSpills(locations, /* core_registers */ false);
orig_offset = stack_offset;
for (uint32_t i : LowToHighBits(fp_spills)) {
DCHECK_LT(i, kMaximumNumberOfExpectedRegisters);
saved_fpu_stack_offsets_[i] = stack_offset;
stack_offset += kArmWordSize;
}
stack_offset = orig_offset;
while (fp_spills != 0u) {
uint32_t begin = CTZ(fp_spills);
uint32_t tmp = fp_spills + (1u << begin);
fp_spills &= tmp; // Clear the contiguous range of 1s.
uint32_t end = (tmp == 0u) ? 32u : CTZ(tmp); // CTZ(0) is undefined.
stack_offset = SaveContiguousSRegisterList(begin, end - 1, codegen, stack_offset);
}
DCHECK_LE(stack_offset, codegen->GetFrameSize() - codegen->FrameEntrySpillSize());
}
void SlowPathCodeARMVIXL::RestoreLiveRegisters(CodeGenerator* codegen, LocationSummary* locations) {
size_t stack_offset = codegen->GetFirstRegisterSlotInSlowPath();
size_t orig_offset = stack_offset;
const uint32_t core_spills = codegen->GetSlowPathSpills(locations, /* core_registers */ true);
for (uint32_t i : LowToHighBits(core_spills)) {
DCHECK_LT(stack_offset, codegen->GetFrameSize() - codegen->FrameEntrySpillSize());
DCHECK_LT(i, kMaximumNumberOfExpectedRegisters);
stack_offset += kArmWordSize;
}
// TODO(VIXL): Check the coherency of stack_offset after this with a test.
CodeGeneratorARMVIXL* arm_codegen = down_cast<CodeGeneratorARMVIXL*>(codegen);
arm_codegen->GetAssembler()->LoadRegisterList(core_spills, orig_offset);
uint32_t fp_spills = codegen->GetSlowPathSpills(locations, /* core_registers */ false);
while (fp_spills != 0u) {
uint32_t begin = CTZ(fp_spills);
uint32_t tmp = fp_spills + (1u << begin);
fp_spills &= tmp; // Clear the contiguous range of 1s.
uint32_t end = (tmp == 0u) ? 32u : CTZ(tmp); // CTZ(0) is undefined.
stack_offset = RestoreContiguousSRegisterList(begin, end - 1, codegen, stack_offset);
}
DCHECK_LE(stack_offset, codegen->GetFrameSize() - codegen->FrameEntrySpillSize());
}
class NullCheckSlowPathARMVIXL : public SlowPathCodeARMVIXL {
public:
explicit NullCheckSlowPathARMVIXL(HNullCheck* instruction) : SlowPathCodeARMVIXL(instruction) {}
void EmitNativeCode(CodeGenerator* codegen) OVERRIDE {
CodeGeneratorARMVIXL* arm_codegen = down_cast<CodeGeneratorARMVIXL*>(codegen);
__ Bind(GetEntryLabel());
if (instruction_->CanThrowIntoCatchBlock()) {
// Live registers will be restored in the catch block if caught.
SaveLiveRegisters(codegen, instruction_->GetLocations());
}
arm_codegen->InvokeRuntime(kQuickThrowNullPointer,
instruction_,
instruction_->GetDexPc(),
this);
CheckEntrypointTypes<kQuickThrowNullPointer, void, void>();
}
bool IsFatal() const OVERRIDE { return true; }
const char* GetDescription() const OVERRIDE { return "NullCheckSlowPathARMVIXL"; }
private:
DISALLOW_COPY_AND_ASSIGN(NullCheckSlowPathARMVIXL);
};
class DivZeroCheckSlowPathARMVIXL : public SlowPathCodeARMVIXL {
public:
explicit DivZeroCheckSlowPathARMVIXL(HDivZeroCheck* instruction)
: SlowPathCodeARMVIXL(instruction) {}
void EmitNativeCode(CodeGenerator* codegen) OVERRIDE {
CodeGeneratorARMVIXL* arm_codegen = down_cast<CodeGeneratorARMVIXL*>(codegen);
__ Bind(GetEntryLabel());
arm_codegen->InvokeRuntime(kQuickThrowDivZero, instruction_, instruction_->GetDexPc(), this);
CheckEntrypointTypes<kQuickThrowDivZero, void, void>();
}
bool IsFatal() const OVERRIDE { return true; }
const char* GetDescription() const OVERRIDE { return "DivZeroCheckSlowPathARMVIXL"; }
private:
DISALLOW_COPY_AND_ASSIGN(DivZeroCheckSlowPathARMVIXL);
};
class SuspendCheckSlowPathARMVIXL : public SlowPathCodeARMVIXL {
public:
SuspendCheckSlowPathARMVIXL(HSuspendCheck* instruction, HBasicBlock* successor)
: SlowPathCodeARMVIXL(instruction), successor_(successor) {}
void EmitNativeCode(CodeGenerator* codegen) OVERRIDE {
CodeGeneratorARMVIXL* arm_codegen = down_cast<CodeGeneratorARMVIXL*>(codegen);
__ Bind(GetEntryLabel());
arm_codegen->InvokeRuntime(kQuickTestSuspend, instruction_, instruction_->GetDexPc(), this);
CheckEntrypointTypes<kQuickTestSuspend, void, void>();
if (successor_ == nullptr) {
__ B(GetReturnLabel());
} else {
__ B(arm_codegen->GetLabelOf(successor_));
}
}
vixl32::Label* GetReturnLabel() {
DCHECK(successor_ == nullptr);
return &return_label_;
}
HBasicBlock* GetSuccessor() const {
return successor_;
}
const char* GetDescription() const OVERRIDE { return "SuspendCheckSlowPathARMVIXL"; }
private:
// If not null, the block to branch to after the suspend check.
HBasicBlock* const successor_;
// If `successor_` is null, the label to branch to after the suspend check.
vixl32::Label return_label_;
DISALLOW_COPY_AND_ASSIGN(SuspendCheckSlowPathARMVIXL);
};
class BoundsCheckSlowPathARMVIXL : public SlowPathCodeARMVIXL {
public:
explicit BoundsCheckSlowPathARMVIXL(HBoundsCheck* instruction)
: SlowPathCodeARMVIXL(instruction) {}
void EmitNativeCode(CodeGenerator* codegen) OVERRIDE {
CodeGeneratorARMVIXL* arm_codegen = down_cast<CodeGeneratorARMVIXL*>(codegen);
LocationSummary* locations = instruction_->GetLocations();
__ Bind(GetEntryLabel());
if (instruction_->CanThrowIntoCatchBlock()) {
// Live registers will be restored in the catch block if caught.
SaveLiveRegisters(codegen, instruction_->GetLocations());
}
// We're moving two locations to locations that could overlap, so we need a parallel
// move resolver.
InvokeRuntimeCallingConventionARMVIXL calling_convention;
codegen->EmitParallelMoves(
locations->InAt(0),
LocationFrom(calling_convention.GetRegisterAt(0)),
Primitive::kPrimInt,
locations->InAt(1),
LocationFrom(calling_convention.GetRegisterAt(1)),
Primitive::kPrimInt);
QuickEntrypointEnum entrypoint = instruction_->AsBoundsCheck()->IsStringCharAt()
? kQuickThrowStringBounds
: kQuickThrowArrayBounds;
arm_codegen->InvokeRuntime(entrypoint, instruction_, instruction_->GetDexPc(), this);
CheckEntrypointTypes<kQuickThrowStringBounds, void, int32_t, int32_t>();
CheckEntrypointTypes<kQuickThrowArrayBounds, void, int32_t, int32_t>();
}
bool IsFatal() const OVERRIDE { return true; }
const char* GetDescription() const OVERRIDE { return "BoundsCheckSlowPathARMVIXL"; }
private:
DISALLOW_COPY_AND_ASSIGN(BoundsCheckSlowPathARMVIXL);
};
class LoadClassSlowPathARMVIXL : public SlowPathCodeARMVIXL {
public:
LoadClassSlowPathARMVIXL(HLoadClass* cls, HInstruction* at, uint32_t dex_pc, bool do_clinit)
: SlowPathCodeARMVIXL(at), cls_(cls), dex_pc_(dex_pc), do_clinit_(do_clinit) {
DCHECK(at->IsLoadClass() || at->IsClinitCheck());
}
void EmitNativeCode(CodeGenerator* codegen) OVERRIDE {
LocationSummary* locations = instruction_->GetLocations();
Location out = locations->Out();
constexpr bool call_saves_everything_except_r0 = (!kUseReadBarrier || kUseBakerReadBarrier);
CodeGeneratorARMVIXL* arm_codegen = down_cast<CodeGeneratorARMVIXL*>(codegen);
__ Bind(GetEntryLabel());
SaveLiveRegisters(codegen, locations);
InvokeRuntimeCallingConventionARMVIXL calling_convention;
// For HLoadClass/kBssEntry/kSaveEverything, make sure we preserve the address of the entry.
DCHECK_EQ(instruction_->IsLoadClass(), cls_ == instruction_);
bool is_load_class_bss_entry =
(cls_ == instruction_) && (cls_->GetLoadKind() == HLoadClass::LoadKind::kBssEntry);
vixl32::Register entry_address;
if (is_load_class_bss_entry && call_saves_everything_except_r0) {
vixl32::Register temp = RegisterFrom(locations->GetTemp(0));
// In the unlucky case that the `temp` is R0, we preserve the address in `out` across
// the kSaveEverything call.
bool temp_is_r0 = temp.Is(calling_convention.GetRegisterAt(0));
entry_address = temp_is_r0 ? RegisterFrom(out) : temp;
DCHECK(!entry_address.Is(calling_convention.GetRegisterAt(0)));
if (temp_is_r0) {
__ Mov(entry_address, temp);
}
}
dex::TypeIndex type_index = cls_->GetTypeIndex();
__ Mov(calling_convention.GetRegisterAt(0), type_index.index_);
QuickEntrypointEnum entrypoint = do_clinit_ ? kQuickInitializeStaticStorage
: kQuickInitializeType;
arm_codegen->InvokeRuntime(entrypoint, instruction_, dex_pc_, this);
if (do_clinit_) {
CheckEntrypointTypes<kQuickInitializeStaticStorage, void*, uint32_t>();
} else {
CheckEntrypointTypes<kQuickInitializeType, void*, uint32_t>();
}
// For HLoadClass/kBssEntry, store the resolved Class to the BSS entry.
if (is_load_class_bss_entry) {
if (call_saves_everything_except_r0) {
// The class entry address was preserved in `entry_address` thanks to kSaveEverything.
__ Str(r0, MemOperand(entry_address));
} else {
// For non-Baker read barrier, we need to re-calculate the address of the string entry.
UseScratchRegisterScope temps(
down_cast<CodeGeneratorARMVIXL*>(codegen)->GetVIXLAssembler());
vixl32::Register temp = temps.Acquire();
CodeGeneratorARMVIXL::PcRelativePatchInfo* labels =
arm_codegen->NewTypeBssEntryPatch(cls_->GetDexFile(), type_index);
arm_codegen->EmitMovwMovtPlaceholder(labels, temp);
__ Str(r0, MemOperand(temp));
}
}
// Move the class to the desired location.
if (out.IsValid()) {
DCHECK(out.IsRegister() && !locations->GetLiveRegisters()->ContainsCoreRegister(out.reg()));
arm_codegen->Move32(locations->Out(), LocationFrom(r0));
}
RestoreLiveRegisters(codegen, locations);
__ B(GetExitLabel());
}
const char* GetDescription() const OVERRIDE { return "LoadClassSlowPathARMVIXL"; }
private:
// The class this slow path will load.
HLoadClass* const cls_;
// The dex PC of `at_`.
const uint32_t dex_pc_;
// Whether to initialize the class.
const bool do_clinit_;
DISALLOW_COPY_AND_ASSIGN(LoadClassSlowPathARMVIXL);
};
class LoadStringSlowPathARMVIXL : public SlowPathCodeARMVIXL {
public:
explicit LoadStringSlowPathARMVIXL(HLoadString* instruction)
: SlowPathCodeARMVIXL(instruction) {}
void EmitNativeCode(CodeGenerator* codegen) OVERRIDE {
DCHECK(instruction_->IsLoadString());
DCHECK_EQ(instruction_->AsLoadString()->GetLoadKind(), HLoadString::LoadKind::kBssEntry);
LocationSummary* locations = instruction_->GetLocations();
DCHECK(!locations->GetLiveRegisters()->ContainsCoreRegister(locations->Out().reg()));
HLoadString* load = instruction_->AsLoadString();
const dex::StringIndex string_index = load->GetStringIndex();
vixl32::Register out = OutputRegister(load);
constexpr bool call_saves_everything_except_r0 = (!kUseReadBarrier || kUseBakerReadBarrier);
CodeGeneratorARMVIXL* arm_codegen = down_cast<CodeGeneratorARMVIXL*>(codegen);
__ Bind(GetEntryLabel());
SaveLiveRegisters(codegen, locations);
InvokeRuntimeCallingConventionARMVIXL calling_convention;
// In the unlucky case that the `temp` is R0, we preserve the address in `out` across
// the kSaveEverything call.
vixl32::Register entry_address;
if (call_saves_everything_except_r0) {
vixl32::Register temp = RegisterFrom(locations->GetTemp(0));
bool temp_is_r0 = (temp.Is(calling_convention.GetRegisterAt(0)));
entry_address = temp_is_r0 ? out : temp;
DCHECK(!entry_address.Is(calling_convention.GetRegisterAt(0)));
if (temp_is_r0) {
__ Mov(entry_address, temp);
}
}
__ Mov(calling_convention.GetRegisterAt(0), string_index.index_);
arm_codegen->InvokeRuntime(kQuickResolveString, instruction_, instruction_->GetDexPc(), this);
CheckEntrypointTypes<kQuickResolveString, void*, uint32_t>();
// Store the resolved String to the .bss entry.
if (call_saves_everything_except_r0) {
// The string entry address was preserved in `entry_address` thanks to kSaveEverything.
__ Str(r0, MemOperand(entry_address));
} else {
// For non-Baker read barrier, we need to re-calculate the address of the string entry.
UseScratchRegisterScope temps(
down_cast<CodeGeneratorARMVIXL*>(codegen)->GetVIXLAssembler());
vixl32::Register temp = temps.Acquire();
CodeGeneratorARMVIXL::PcRelativePatchInfo* labels =
arm_codegen->NewPcRelativeStringPatch(load->GetDexFile(), string_index);
arm_codegen->EmitMovwMovtPlaceholder(labels, temp);
__ Str(r0, MemOperand(temp));
}
arm_codegen->Move32(locations->Out(), LocationFrom(r0));
RestoreLiveRegisters(codegen, locations);
__ B(GetExitLabel());
}
const char* GetDescription() const OVERRIDE { return "LoadStringSlowPathARMVIXL"; }
private:
DISALLOW_COPY_AND_ASSIGN(LoadStringSlowPathARMVIXL);
};
class TypeCheckSlowPathARMVIXL : public SlowPathCodeARMVIXL {
public:
TypeCheckSlowPathARMVIXL(HInstruction* instruction, bool is_fatal)
: SlowPathCodeARMVIXL(instruction), is_fatal_(is_fatal) {}
void EmitNativeCode(CodeGenerator* codegen) OVERRIDE {
LocationSummary* locations = instruction_->GetLocations();
DCHECK(instruction_->IsCheckCast()
|| !locations->GetLiveRegisters()->ContainsCoreRegister(locations->Out().reg()));
CodeGeneratorARMVIXL* arm_codegen = down_cast<CodeGeneratorARMVIXL*>(codegen);
__ Bind(GetEntryLabel());
if (!is_fatal_) {
SaveLiveRegisters(codegen, locations);
}
// We're moving two locations to locations that could overlap, so we need a parallel
// move resolver.
InvokeRuntimeCallingConventionARMVIXL calling_convention;
codegen->EmitParallelMoves(locations->InAt(0),
LocationFrom(calling_convention.GetRegisterAt(0)),
Primitive::kPrimNot,
locations->InAt(1),
LocationFrom(calling_convention.GetRegisterAt(1)),
Primitive::kPrimNot);
if (instruction_->IsInstanceOf()) {
arm_codegen->InvokeRuntime(kQuickInstanceofNonTrivial,
instruction_,
instruction_->GetDexPc(),
this);
CheckEntrypointTypes<kQuickInstanceofNonTrivial, size_t, mirror::Object*, mirror::Class*>();
arm_codegen->Move32(locations->Out(), LocationFrom(r0));
} else {
DCHECK(instruction_->IsCheckCast());
arm_codegen->InvokeRuntime(kQuickCheckInstanceOf,
instruction_,
instruction_->GetDexPc(),
this);
CheckEntrypointTypes<kQuickCheckInstanceOf, void, mirror::Object*, mirror::Class*>();
}
if (!is_fatal_) {
RestoreLiveRegisters(codegen, locations);
__ B(GetExitLabel());
}
}
const char* GetDescription() const OVERRIDE { return "TypeCheckSlowPathARMVIXL"; }
bool IsFatal() const OVERRIDE { return is_fatal_; }
private:
const bool is_fatal_;
DISALLOW_COPY_AND_ASSIGN(TypeCheckSlowPathARMVIXL);
};
class DeoptimizationSlowPathARMVIXL : public SlowPathCodeARMVIXL {
public:
explicit DeoptimizationSlowPathARMVIXL(HDeoptimize* instruction)
: SlowPathCodeARMVIXL(instruction) {}
void EmitNativeCode(CodeGenerator* codegen) OVERRIDE {
CodeGeneratorARMVIXL* arm_codegen = down_cast<CodeGeneratorARMVIXL*>(codegen);
__ Bind(GetEntryLabel());
LocationSummary* locations = instruction_->GetLocations();
SaveLiveRegisters(codegen, locations);
InvokeRuntimeCallingConventionARMVIXL calling_convention;
__ Mov(calling_convention.GetRegisterAt(0),
static_cast<uint32_t>(instruction_->AsDeoptimize()->GetDeoptimizationKind()));
arm_codegen->InvokeRuntime(kQuickDeoptimize, instruction_, instruction_->GetDexPc(), this);
CheckEntrypointTypes<kQuickDeoptimize, void, DeoptimizationKind>();
}
const char* GetDescription() const OVERRIDE { return "DeoptimizationSlowPathARMVIXL"; }
private:
DISALLOW_COPY_AND_ASSIGN(DeoptimizationSlowPathARMVIXL);
};
class ArraySetSlowPathARMVIXL : public SlowPathCodeARMVIXL {
public:
explicit ArraySetSlowPathARMVIXL(HInstruction* instruction) : SlowPathCodeARMVIXL(instruction) {}
void EmitNativeCode(CodeGenerator* codegen) OVERRIDE {
LocationSummary* locations = instruction_->GetLocations();
__ Bind(GetEntryLabel());
SaveLiveRegisters(codegen, locations);
InvokeRuntimeCallingConventionARMVIXL calling_convention;
HParallelMove parallel_move(codegen->GetGraph()->GetArena());
parallel_move.AddMove(
locations->InAt(0),
LocationFrom(calling_convention.GetRegisterAt(0)),
Primitive::kPrimNot,
nullptr);
parallel_move.AddMove(
locations->InAt(1),
LocationFrom(calling_convention.GetRegisterAt(1)),
Primitive::kPrimInt,
nullptr);
parallel_move.AddMove(
locations->InAt(2),
LocationFrom(calling_convention.GetRegisterAt(2)),
Primitive::kPrimNot,
nullptr);
codegen->GetMoveResolver()->EmitNativeCode(&parallel_move);
CodeGeneratorARMVIXL* arm_codegen = down_cast<CodeGeneratorARMVIXL*>(codegen);
arm_codegen->InvokeRuntime(kQuickAputObject, instruction_, instruction_->GetDexPc(), this);
CheckEntrypointTypes<kQuickAputObject, void, mirror::Array*, int32_t, mirror::Object*>();
RestoreLiveRegisters(codegen, locations);
__ B(GetExitLabel());
}
const char* GetDescription() const OVERRIDE { return "ArraySetSlowPathARMVIXL"; }
private:
DISALLOW_COPY_AND_ASSIGN(ArraySetSlowPathARMVIXL);
};
// Abstract base class for read barrier slow paths marking a reference
// `ref`.
//
// Argument `entrypoint` must be a register location holding the read
// barrier marking runtime entry point to be invoked.
class ReadBarrierMarkSlowPathBaseARMVIXL : public SlowPathCodeARMVIXL {
protected:
ReadBarrierMarkSlowPathBaseARMVIXL(HInstruction* instruction, Location ref, Location entrypoint)
: SlowPathCodeARMVIXL(instruction), ref_(ref), entrypoint_(entrypoint) {
DCHECK(kEmitCompilerReadBarrier);
}
const char* GetDescription() const OVERRIDE { return "ReadBarrierMarkSlowPathBaseARMVIXL"; }
// Generate assembly code calling the read barrier marking runtime
// entry point (ReadBarrierMarkRegX).
void GenerateReadBarrierMarkRuntimeCall(CodeGenerator* codegen) {
vixl32::Register ref_reg = RegisterFrom(ref_);
// No need to save live registers; it's taken care of by the
// entrypoint. Also, there is no need to update the stack mask,
// as this runtime call will not trigger a garbage collection.
CodeGeneratorARMVIXL* arm_codegen = down_cast<CodeGeneratorARMVIXL*>(codegen);
DCHECK(!ref_reg.Is(sp));
DCHECK(!ref_reg.Is(lr));
DCHECK(!ref_reg.Is(pc));
// IP is used internally by the ReadBarrierMarkRegX entry point
// as a temporary, it cannot be the entry point's input/output.
DCHECK(!ref_reg.Is(ip));
DCHECK(ref_reg.IsRegister()) << ref_reg;
// "Compact" slow path, saving two moves.
//
// Instead of using the standard runtime calling convention (input
// and output in R0):
//
// R0 <- ref
// R0 <- ReadBarrierMark(R0)
// ref <- R0
//
// we just use rX (the register containing `ref`) as input and output
// of a dedicated entrypoint:
//
// rX <- ReadBarrierMarkRegX(rX)
//
if (entrypoint_.IsValid()) {
arm_codegen->ValidateInvokeRuntimeWithoutRecordingPcInfo(instruction_, this);
__ Blx(RegisterFrom(entrypoint_));
} else {
// Entrypoint is not already loaded, load from the thread.
int32_t entry_point_offset =
CodeGenerator::GetReadBarrierMarkEntryPointsOffset<kArmPointerSize>(ref_reg.GetCode());
// This runtime call does not require a stack map.
arm_codegen->InvokeRuntimeWithoutRecordingPcInfo(entry_point_offset, instruction_, this);
}
}
// The location (register) of the marked object reference.
const Location ref_;
// The location of the entrypoint if already loaded.
const Location entrypoint_;
private:
DISALLOW_COPY_AND_ASSIGN(ReadBarrierMarkSlowPathBaseARMVIXL);
};
// Slow path marking an object reference `ref` during a read
// barrier. The field `obj.field` in the object `obj` holding this
// reference does not get updated by this slow path after marking.
//
// This means that after the execution of this slow path, `ref` will
// always be up-to-date, but `obj.field` may not; i.e., after the
// flip, `ref` will be a to-space reference, but `obj.field` will
// probably still be a from-space reference (unless it gets updated by
// another thread, or if another thread installed another object
// reference (different from `ref`) in `obj.field`).
//
// If `entrypoint` is a valid location it is assumed to already be
// holding the entrypoint. The case where the entrypoint is passed in
// is when the decision to mark is based on whether the GC is marking.
class ReadBarrierMarkSlowPathARMVIXL : public ReadBarrierMarkSlowPathBaseARMVIXL {
public:
ReadBarrierMarkSlowPathARMVIXL(HInstruction* instruction,
Location ref,
Location entrypoint = Location::NoLocation())
: ReadBarrierMarkSlowPathBaseARMVIXL(instruction, ref, entrypoint) {
DCHECK(kEmitCompilerReadBarrier);
}
const char* GetDescription() const OVERRIDE { return "ReadBarrierMarkSlowPathARMVIXL"; }
void EmitNativeCode(CodeGenerator* codegen) OVERRIDE {
LocationSummary* locations = instruction_->GetLocations();
DCHECK(locations->CanCall());
DCHECK(ref_.IsRegister()) << ref_;
DCHECK(!locations->GetLiveRegisters()->ContainsCoreRegister(ref_.reg())) << ref_.reg();
DCHECK(instruction_->IsLoadClass() || instruction_->IsLoadString())
<< "Unexpected instruction in read barrier marking slow path: "
<< instruction_->DebugName();
__ Bind(GetEntryLabel());
GenerateReadBarrierMarkRuntimeCall(codegen);
__ B(GetExitLabel());
}
private:
DISALLOW_COPY_AND_ASSIGN(ReadBarrierMarkSlowPathARMVIXL);
};
// Slow path loading `obj`'s lock word, loading a reference from
// object `*(obj + offset + (index << scale_factor))` into `ref`, and
// marking `ref` if `obj` is gray according to the lock word (Baker
// read barrier). The field `obj.field` in the object `obj` holding
// this reference does not get updated by this slow path after marking
// (see LoadReferenceWithBakerReadBarrierAndUpdateFieldSlowPathARMVIXL
// below for that).
//
// This means that after the execution of this slow path, `ref` will
// always be up-to-date, but `obj.field` may not; i.e., after the
// flip, `ref` will be a to-space reference, but `obj.field` will
// probably still be a from-space reference (unless it gets updated by
// another thread, or if another thread installed another object
// reference (different from `ref`) in `obj.field`).
//
// Argument `entrypoint` must be a register location holding the read
// barrier marking runtime entry point to be invoked.
class LoadReferenceWithBakerReadBarrierSlowPathARMVIXL : public ReadBarrierMarkSlowPathBaseARMVIXL {
public:
LoadReferenceWithBakerReadBarrierSlowPathARMVIXL(HInstruction* instruction,
Location ref,
vixl32::Register obj,
uint32_t offset,
Location index,
ScaleFactor scale_factor,
bool needs_null_check,
vixl32::Register temp,
Location entrypoint)
: ReadBarrierMarkSlowPathBaseARMVIXL(instruction, ref, entrypoint),
obj_(obj),
offset_(offset),
index_(index),
scale_factor_(scale_factor),
needs_null_check_(needs_null_check),
temp_(temp) {
DCHECK(kEmitCompilerReadBarrier);
DCHECK(kUseBakerReadBarrier);
}
const char* GetDescription() const OVERRIDE {
return "LoadReferenceWithBakerReadBarrierSlowPathARMVIXL";
}
void EmitNativeCode(CodeGenerator* codegen) OVERRIDE {
LocationSummary* locations = instruction_->GetLocations();
vixl32::Register ref_reg = RegisterFrom(ref_);
DCHECK(locations->CanCall());
DCHECK(!locations->GetLiveRegisters()->ContainsCoreRegister(ref_reg.GetCode())) << ref_reg;
DCHECK(instruction_->IsInstanceFieldGet() ||
instruction_->IsStaticFieldGet() ||
instruction_->IsArrayGet() ||
instruction_->IsArraySet() ||
instruction_->IsInstanceOf() ||
instruction_->IsCheckCast() ||
(instruction_->IsInvokeVirtual() && instruction_->GetLocations()->Intrinsified()) ||
(instruction_->IsInvokeStaticOrDirect() && instruction_->GetLocations()->Intrinsified()))
<< "Unexpected instruction in read barrier marking slow path: "
<< instruction_->DebugName();
// The read barrier instrumentation of object ArrayGet
// instructions does not support the HIntermediateAddress
// instruction.
DCHECK(!(instruction_->IsArrayGet() &&
instruction_->AsArrayGet()->GetArray()->IsIntermediateAddress()));
// Temporary register `temp_`, used to store the lock word, must
// not be IP, as we may use it to emit the reference load (in the
// call to GenerateRawReferenceLoad below), and we need the lock
// word to still be in `temp_` after the reference load.
DCHECK(!temp_.Is(ip));
__ Bind(GetEntryLabel());
// When using MaybeGenerateReadBarrierSlow, the read barrier call is
// inserted after the original load. However, in fast path based
// Baker's read barriers, we need to perform the load of
// mirror::Object::monitor_ *before* the original reference load.
// This load-load ordering is required by the read barrier.
// The slow path (for Baker's algorithm) should look like:
//
// uint32_t rb_state = Lockword(obj->monitor_).ReadBarrierState();
// lfence; // Load fence or artificial data dependency to prevent load-load reordering
// HeapReference<mirror::Object> ref = *src; // Original reference load.
// bool is_gray = (rb_state == ReadBarrier::GrayState());
// if (is_gray) {
// ref = entrypoint(ref); // ref = ReadBarrier::Mark(ref); // Runtime entry point call.
// }
//
// Note: the original implementation in ReadBarrier::Barrier is
// slightly more complex as it performs additional checks that we do
// not do here for performance reasons.
CodeGeneratorARMVIXL* arm_codegen = down_cast<CodeGeneratorARMVIXL*>(codegen);
// /* int32_t */ monitor = obj->monitor_
uint32_t monitor_offset = mirror::Object::MonitorOffset().Int32Value();
arm_codegen->GetAssembler()->LoadFromOffset(kLoadWord, temp_, obj_, monitor_offset);
if (needs_null_check_) {
codegen->MaybeRecordImplicitNullCheck(instruction_);
}
// /* LockWord */ lock_word = LockWord(monitor)
static_assert(sizeof(LockWord) == sizeof(int32_t),
"art::LockWord and int32_t have different sizes.");
// Introduce a dependency on the lock_word including the rb_state,
// which shall prevent load-load reordering without using
// a memory barrier (which would be more expensive).
// `obj` is unchanged by this operation, but its value now depends
// on `temp`.
__ Add(obj_, obj_, Operand(temp_, ShiftType::LSR, 32));
// The actual reference load.
// A possible implicit null check has already been handled above.
arm_codegen->GenerateRawReferenceLoad(
instruction_, ref_, obj_, offset_, index_, scale_factor_, /* needs_null_check */ false);
// Mark the object `ref` when `obj` is gray.
//
// if (rb_state == ReadBarrier::GrayState())
// ref = ReadBarrier::Mark(ref);
//
// Given the numeric representation, it's enough to check the low bit of the
// rb_state. We do that by shifting the bit out of the lock word with LSRS
// which can be a 16-bit instruction unlike the TST immediate.
static_assert(ReadBarrier::WhiteState() == 0, "Expecting white to have value 0");
static_assert(ReadBarrier::GrayState() == 1, "Expecting gray to have value 1");
__ Lsrs(temp_, temp_, LockWord::kReadBarrierStateShift + 1);
__ B(cc, GetExitLabel()); // Carry flag is the last bit shifted out by LSRS.
GenerateReadBarrierMarkRuntimeCall(codegen);
__ B(GetExitLabel());
}
private:
// The register containing the object holding the marked object reference field.
vixl32::Register obj_;
// The offset, index and scale factor to access the reference in `obj_`.
uint32_t offset_;
Location index_;
ScaleFactor scale_factor_;
// Is a null check required?
bool needs_null_check_;
// A temporary register used to hold the lock word of `obj_`.
vixl32::Register temp_;
DISALLOW_COPY_AND_ASSIGN(LoadReferenceWithBakerReadBarrierSlowPathARMVIXL);
};
// Slow path loading `obj`'s lock word, loading a reference from
// object `*(obj + offset + (index << scale_factor))` into `ref`, and
// marking `ref` if `obj` is gray according to the lock word (Baker
// read barrier). If needed, this slow path also atomically updates
// the field `obj.field` in the object `obj` holding this reference
// after marking (contrary to
// LoadReferenceWithBakerReadBarrierSlowPathARMVIXL above, which never
// tries to update `obj.field`).
//
// This means that after the execution of this slow path, both `ref`
// and `obj.field` will be up-to-date; i.e., after the flip, both will
// hold the same to-space reference (unless another thread installed
// another object reference (different from `ref`) in `obj.field`).
//
//
// Argument `entrypoint` must be a register location holding the read
// barrier marking runtime entry point to be invoked.
class LoadReferenceWithBakerReadBarrierAndUpdateFieldSlowPathARMVIXL
: public ReadBarrierMarkSlowPathBaseARMVIXL {
public:
LoadReferenceWithBakerReadBarrierAndUpdateFieldSlowPathARMVIXL(HInstruction* instruction,
Location ref,
vixl32::Register obj,
uint32_t offset,
Location index,
ScaleFactor scale_factor,
bool needs_null_check,
vixl32::Register temp1,
vixl32::Register temp2,
Location entrypoint)
: ReadBarrierMarkSlowPathBaseARMVIXL(instruction, ref, entrypoint),
obj_(obj),
offset_(offset),
index_(index),
scale_factor_(scale_factor),
needs_null_check_(needs_null_check),
temp1_(temp1),
temp2_(temp2) {
DCHECK(kEmitCompilerReadBarrier);
DCHECK(kUseBakerReadBarrier);
}
const char* GetDescription() const OVERRIDE {
return "LoadReferenceWithBakerReadBarrierAndUpdateFieldSlowPathARMVIXL";
}
void EmitNativeCode(CodeGenerator* codegen) OVERRIDE {
LocationSummary* locations = instruction_->GetLocations();
vixl32::Register ref_reg = RegisterFrom(ref_);
DCHECK(locations->CanCall());
DCHECK(!locations->GetLiveRegisters()->ContainsCoreRegister(ref_reg.GetCode())) << ref_reg;
DCHECK_NE(ref_.reg(), LocationFrom(temp1_).reg());
// This slow path is only used by the UnsafeCASObject intrinsic at the moment.
DCHECK((instruction_->IsInvokeVirtual() && instruction_->GetLocations()->Intrinsified()))
<< "Unexpected instruction in read barrier marking and field updating slow path: "
<< instruction_->DebugName();
DCHECK(instruction_->GetLocations()->Intrinsified());
DCHECK_EQ(instruction_->AsInvoke()->GetIntrinsic(), Intrinsics::kUnsafeCASObject);
DCHECK_EQ(offset_, 0u);
DCHECK_EQ(scale_factor_, ScaleFactor::TIMES_1);
Location field_offset = index_;
DCHECK(field_offset.IsRegisterPair()) << field_offset;
// Temporary register `temp1_`, used to store the lock word, must
// not be IP, as we may use it to emit the reference load (in the
// call to GenerateRawReferenceLoad below), and we need the lock
// word to still be in `temp1_` after the reference load.
DCHECK(!temp1_.Is(ip));
__ Bind(GetEntryLabel());
// The implementation is similar to LoadReferenceWithBakerReadBarrierSlowPathARMVIXL's:
//
// uint32_t rb_state = Lockword(obj->monitor_).ReadBarrierState();
// lfence; // Load fence or artificial data dependency to prevent load-load reordering
// HeapReference<mirror::Object> ref = *src; // Original reference load.
// bool is_gray = (rb_state == ReadBarrier::GrayState());
// if (is_gray) {
// old_ref = ref;
// ref = entrypoint(ref); // ref = ReadBarrier::Mark(ref); // Runtime entry point call.
// compareAndSwapObject(obj, field_offset, old_ref, ref);
// }
CodeGeneratorARMVIXL* arm_codegen = down_cast<CodeGeneratorARMVIXL*>(codegen);
// /* int32_t */ monitor = obj->monitor_
uint32_t monitor_offset = mirror::Object::MonitorOffset().Int32Value();
arm_codegen->GetAssembler()->LoadFromOffset(kLoadWord, temp1_, obj_, monitor_offset);
if (needs_null_check_) {
codegen->MaybeRecordImplicitNullCheck(instruction_);
}
// /* LockWord */ lock_word = LockWord(monitor)
static_assert(sizeof(LockWord) == sizeof(int32_t),
"art::LockWord and int32_t have different sizes.");
// Introduce a dependency on the lock_word including the rb_state,
// which shall prevent load-load reordering without using
// a memory barrier (which would be more expensive).
// `obj` is unchanged by this operation, but its value now depends
// on `temp`.
__ Add(obj_, obj_, Operand(temp1_, ShiftType::LSR, 32));
// The actual reference load.
// A possible implicit null check has already been handled above.
arm_codegen->GenerateRawReferenceLoad(
instruction_, ref_, obj_, offset_, index_, scale_factor_, /* needs_null_check */ false);
// Mark the object `ref` when `obj` is gray.
//
// if (rb_state == ReadBarrier::GrayState())
// ref = ReadBarrier::Mark(ref);
//
// Given the numeric representation, it's enough to check the low bit of the
// rb_state. We do that by shifting the bit out of the lock word with LSRS
// which can be a 16-bit instruction unlike the TST immediate.
static_assert(ReadBarrier::WhiteState() == 0, "Expecting white to have value 0");
static_assert(ReadBarrier::GrayState() == 1, "Expecting gray to have value 1");
__ Lsrs(temp1_, temp1_, LockWord::kReadBarrierStateShift + 1);
__ B(cc, GetExitLabel()); // Carry flag is the last bit shifted out by LSRS.
// Save the old value of the reference before marking it.
// Note that we cannot use IP to save the old reference, as IP is
// used internally by the ReadBarrierMarkRegX entry point, and we
// need the old reference after the call to that entry point.
DCHECK(!temp1_.Is(ip));
__ Mov(temp1_, ref_reg);
GenerateReadBarrierMarkRuntimeCall(codegen);
// If the new reference is different from the old reference,
// update the field in the holder (`*(obj_ + field_offset)`).
//
// Note that this field could also hold a different object, if
// another thread had concurrently changed it. In that case, the
// LDREX/SUBS/ITNE sequence of instructions in the compare-and-set
// (CAS) operation below would abort the CAS, leaving the field
// as-is.
__ Cmp(temp1_, ref_reg);
__ B(eq, GetExitLabel());
// Update the the holder's field atomically. This may fail if
// mutator updates before us, but it's OK. This is achieved
// using a strong compare-and-set (CAS) operation with relaxed
// memory synchronization ordering, where the expected value is
// the old reference and the desired value is the new reference.
UseScratchRegisterScope temps(arm_codegen->GetVIXLAssembler());
// Convenience aliases.
vixl32::Register base = obj_;
// The UnsafeCASObject intrinsic uses a register pair as field
// offset ("long offset"), of which only the low part contains
// data.
vixl32::Register offset = LowRegisterFrom(field_offset);
vixl32::Register expected = temp1_;
vixl32::Register value = ref_reg;
vixl32::Register tmp_ptr = temps.Acquire(); // Pointer to actual memory.
vixl32::Register tmp = temp2_; // Value in memory.
__ Add(tmp_ptr, base, offset);
if (kPoisonHeapReferences) {
arm_codegen->GetAssembler()->PoisonHeapReference(expected);
if (value.Is(expected)) {
// Do not poison `value`, as it is the same register as
// `expected`, which has just been poisoned.
} else {
arm_codegen->GetAssembler()->PoisonHeapReference(value);
}
}
// do {
// tmp = [r_ptr] - expected;
// } while (tmp == 0 && failure([r_ptr] <- r_new_value));
vixl32::Label loop_head, exit_loop;
__ Bind(&loop_head);
__ Ldrex(tmp, MemOperand(tmp_ptr));
__ Subs(tmp, tmp, expected);
{
ExactAssemblyScope aas(arm_codegen->GetVIXLAssembler(),
2 * kMaxInstructionSizeInBytes,
CodeBufferCheckScope::kMaximumSize);
__ it(ne);
__ clrex(ne);
}
__ B(ne, &exit_loop, /* far_target */ false);
__ Strex(tmp, value, MemOperand(tmp_ptr));
__ Cmp(tmp, 1);
__ B(eq, &loop_head, /* far_target */ false);
__ Bind(&exit_loop);
if (kPoisonHeapReferences) {
arm_codegen->GetAssembler()->UnpoisonHeapReference(expected);
if (value.Is(expected)) {
// Do not unpoison `value`, as it is the same register as
// `expected`, which has just been unpoisoned.
} else {
arm_codegen->GetAssembler()->UnpoisonHeapReference(value);
}
}
__ B(GetExitLabel());
}
private:
// The register containing the object holding the marked object reference field.
const vixl32::Register obj_;
// The offset, index and scale factor to access the reference in `obj_`.
uint32_t offset_;
Location index_;
ScaleFactor scale_factor_;
// Is a null check required?
bool needs_null_check_;
// A temporary register used to hold the lock word of `obj_`; and
// also to hold the original reference value, when the reference is
// marked.
const vixl32::Register temp1_;
// A temporary register used in the implementation of the CAS, to
// update the object's reference field.
const vixl32::Register temp2_;
DISALLOW_COPY_AND_ASSIGN(LoadReferenceWithBakerReadBarrierAndUpdateFieldSlowPathARMVIXL);
};
// Slow path generating a read barrier for a heap reference.
class ReadBarrierForHeapReferenceSlowPathARMVIXL : public SlowPathCodeARMVIXL {
public:
ReadBarrierForHeapReferenceSlowPathARMVIXL(HInstruction* instruction,
Location out,
Location ref,
Location obj,
uint32_t offset,
Location index)
: SlowPathCodeARMVIXL(instruction),
out_(out),
ref_(ref),
obj_(obj),
offset_(offset),
index_(index) {
DCHECK(kEmitCompilerReadBarrier);
// If `obj` is equal to `out` or `ref`, it means the initial object
// has been overwritten by (or after) the heap object reference load
// to be instrumented, e.g.:
//
// __ LoadFromOffset(kLoadWord, out, out, offset);
// codegen_->GenerateReadBarrierSlow(instruction, out_loc, out_loc, out_loc, offset);
//
// In that case, we have lost the information about the original
// object, and the emitted read barrier cannot work properly.
DCHECK(!obj.Equals(out)) << "obj=" << obj << " out=" << out;
DCHECK(!obj.Equals(ref)) << "obj=" << obj << " ref=" << ref;
}
void EmitNativeCode(CodeGenerator* codegen) OVERRIDE {
CodeGeneratorARMVIXL* arm_codegen = down_cast<CodeGeneratorARMVIXL*>(codegen);
LocationSummary* locations = instruction_->GetLocations();
vixl32::Register reg_out = RegisterFrom(out_);
DCHECK(locations->CanCall());
DCHECK(!locations->GetLiveRegisters()->ContainsCoreRegister(reg_out.GetCode()));
DCHECK(instruction_->IsInstanceFieldGet() ||
instruction_->IsStaticFieldGet() ||
instruction_->IsArrayGet() ||
instruction_->IsInstanceOf() ||
instruction_->IsCheckCast() ||
(instruction_->IsInvokeVirtual() && instruction_->GetLocations()->Intrinsified()))
<< "Unexpected instruction in read barrier for heap reference slow path: "
<< instruction_->DebugName();
// The read barrier instrumentation of object ArrayGet
// instructions does not support the HIntermediateAddress
// instruction.
DCHECK(!(instruction_->IsArrayGet() &&
instruction_->AsArrayGet()->GetArray()->IsIntermediateAddress()));
__ Bind(GetEntryLabel());
SaveLiveRegisters(codegen, locations);
// We may have to change the index's value, but as `index_` is a
// constant member (like other "inputs" of this slow path),
// introduce a copy of it, `index`.
Location index = index_;
if (index_.IsValid()) {
// Handle `index_` for HArrayGet and UnsafeGetObject/UnsafeGetObjectVolatile intrinsics.
if (instruction_->IsArrayGet()) {
// Compute the actual memory offset and store it in `index`.
vixl32::Register index_reg = RegisterFrom(index_);
DCHECK(locations->GetLiveRegisters()->ContainsCoreRegister(index_reg.GetCode()));
if (codegen->IsCoreCalleeSaveRegister(index_reg.GetCode())) {
// We are about to change the value of `index_reg` (see the
// calls to art::arm::Thumb2Assembler::Lsl and
// art::arm::Thumb2Assembler::AddConstant below), but it has
// not been saved by the previous call to
// art::SlowPathCode::SaveLiveRegisters, as it is a
// callee-save register --
// art::SlowPathCode::SaveLiveRegisters does not consider
// callee-save registers, as it has been designed with the
// assumption that callee-save registers are supposed to be
// handled by the called function. So, as a callee-save
// register, `index_reg` _would_ eventually be saved onto
// the stack, but it would be too late: we would have
// changed its value earlier. Therefore, we manually save
// it here into another freely available register,
// `free_reg`, chosen of course among the caller-save
// registers (as a callee-save `free_reg` register would
// exhibit the same problem).
//
// Note we could have requested a temporary register from
// the register allocator instead; but we prefer not to, as
// this is a slow path, and we know we can find a
// caller-save register that is available.
vixl32::Register free_reg = FindAvailableCallerSaveRegister(codegen);
__ Mov(free_reg, index_reg);
index_reg = free_reg;
index = LocationFrom(index_reg);
} else {
// The initial register stored in `index_` has already been
// saved in the call to art::SlowPathCode::SaveLiveRegisters
// (as it is not a callee-save register), so we can freely
// use it.
}
// Shifting the index value contained in `index_reg` by the scale
// factor (2) cannot overflow in practice, as the runtime is
// unable to allocate object arrays with a size larger than
// 2^26 - 1 (that is, 2^28 - 4 bytes).
__ Lsl(index_reg, index_reg, TIMES_4);
static_assert(
sizeof(mirror::HeapReference<mirror::Object>) == sizeof(int32_t),
"art::mirror::HeapReference<art::mirror::Object> and int32_t have different sizes.");
__ Add(index_reg, index_reg, offset_);
} else {
// In the case of the UnsafeGetObject/UnsafeGetObjectVolatile
// intrinsics, `index_` is not shifted by a scale factor of 2
// (as in the case of ArrayGet), as it is actually an offset
// to an object field within an object.
DCHECK(instruction_->IsInvoke()) << instruction_->DebugName();
DCHECK(instruction_->GetLocations()->Intrinsified());
DCHECK((instruction_->AsInvoke()->GetIntrinsic() == Intrinsics::kUnsafeGetObject) ||
(instruction_->AsInvoke()->GetIntrinsic() == Intrinsics::kUnsafeGetObjectVolatile))
<< instruction_->AsInvoke()->GetIntrinsic();
DCHECK_EQ(offset_, 0U);
DCHECK(index_.IsRegisterPair());
// UnsafeGet's offset location is a register pair, the low
// part contains the correct offset.
index = index_.ToLow();
}
}
// We're moving two or three locations to locations that could
// overlap, so we need a parallel move resolver.
InvokeRuntimeCallingConventionARMVIXL calling_convention;
HParallelMove parallel_move(codegen->GetGraph()->GetArena());
parallel_move.AddMove(ref_,
LocationFrom(calling_convention.GetRegisterAt(0)),
Primitive::kPrimNot,
nullptr);
parallel_move.AddMove(obj_,
LocationFrom(calling_convention.GetRegisterAt(1)),
Primitive::kPrimNot,
nullptr);
if (index.IsValid()) {
parallel_move.AddMove(index,
LocationFrom(calling_convention.GetRegisterAt(2)),
Primitive::kPrimInt,
nullptr);
codegen->GetMoveResolver()->EmitNativeCode(&parallel_move);
} else {
codegen->GetMoveResolver()->EmitNativeCode(&parallel_move);
__ Mov(calling_convention.GetRegisterAt(2), offset_);
}
arm_codegen->InvokeRuntime(kQuickReadBarrierSlow, instruction_, instruction_->GetDexPc(), this);
CheckEntrypointTypes<
kQuickReadBarrierSlow, mirror::Object*, mirror::Object*, mirror::Object*, uint32_t>();
arm_codegen->Move32(out_, LocationFrom(r0));
RestoreLiveRegisters(codegen, locations);
__ B(GetExitLabel());
}
const char* GetDescription() const OVERRIDE {
return "ReadBarrierForHeapReferenceSlowPathARMVIXL";
}
private:
vixl32::Register FindAvailableCallerSaveRegister(CodeGenerator* codegen) {
uint32_t ref = RegisterFrom(ref_).GetCode();
uint32_t obj = RegisterFrom(obj_).GetCode();
for (uint32_t i = 0, e = codegen->GetNumberOfCoreRegisters(); i < e; ++i) {
if (i != ref && i != obj && !codegen->IsCoreCalleeSaveRegister(i)) {
return vixl32::Register(i);
}
}
// We shall never fail to find a free caller-save register, as
// there are more than two core caller-save registers on ARM
// (meaning it is possible to find one which is different from
// `ref` and `obj`).
DCHECK_GT(codegen->GetNumberOfCoreCallerSaveRegisters(), 2u);
LOG(FATAL) << "Could not find a free caller-save register";
UNREACHABLE();
}
const Location out_;
const Location ref_;
const Location obj_;
const uint32_t offset_;
// An additional location containing an index to an array.
// Only used for HArrayGet and the UnsafeGetObject &
// UnsafeGetObjectVolatile intrinsics.
const Location index_;
DISALLOW_COPY_AND_ASSIGN(ReadBarrierForHeapReferenceSlowPathARMVIXL);
};
// Slow path generating a read barrier for a GC root.
class ReadBarrierForRootSlowPathARMVIXL : public SlowPathCodeARMVIXL {
public:
ReadBarrierForRootSlowPathARMVIXL(HInstruction* instruction, Location out, Location root)
: SlowPathCodeARMVIXL(instruction), out_(out), root_(root) {
DCHECK(kEmitCompilerReadBarrier);
}
void EmitNativeCode(CodeGenerator* codegen) OVERRIDE {
LocationSummary* locations = instruction_->GetLocations();
vixl32::Register reg_out = RegisterFrom(out_);
DCHECK(locations->CanCall());
DCHECK(!locations->GetLiveRegisters()->ContainsCoreRegister(reg_out.GetCode()));
DCHECK(instruction_->IsLoadClass() || instruction_->IsLoadString())
<< "Unexpected instruction in read barrier for GC root slow path: "
<< instruction_->DebugName();
__ Bind(GetEntryLabel());
SaveLiveRegisters(codegen, locations);
InvokeRuntimeCallingConventionARMVIXL calling_convention;
CodeGeneratorARMVIXL* arm_codegen = down_cast<CodeGeneratorARMVIXL*>(codegen);
arm_codegen->Move32(LocationFrom(calling_convention.GetRegisterAt(0)), root_);
arm_codegen->InvokeRuntime(kQuickReadBarrierForRootSlow,
instruction_,
instruction_->GetDexPc(),
this);
CheckEntrypointTypes<kQuickReadBarrierForRootSlow, mirror::Object*, GcRoot<mirror::Object>*>();
arm_codegen->Move32(out_, LocationFrom(r0));
RestoreLiveRegisters(codegen, locations);
__ B(GetExitLabel());
}
const char* GetDescription() const OVERRIDE { return "ReadBarrierForRootSlowPathARMVIXL"; }
private:
const Location out_;
const Location root_;
DISALLOW_COPY_AND_ASSIGN(ReadBarrierForRootSlowPathARMVIXL);
};
inline vixl32::Condition ARMCondition(IfCondition cond) {
switch (cond) {
case kCondEQ: return eq;
case kCondNE: return ne;
case kCondLT: return lt;
case kCondLE: return le;
case kCondGT: return gt;
case kCondGE: return ge;
case kCondB: return lo;
case kCondBE: return ls;
case kCondA: return hi;
case kCondAE: return hs;
}
LOG(FATAL) << "Unreachable";
UNREACHABLE();
}
// Maps signed condition to unsigned condition.
inline vixl32::Condition ARMUnsignedCondition(IfCondition cond) {
switch (cond) {
case kCondEQ: return eq;
case kCondNE: return ne;
// Signed to unsigned.
case kCondLT: return lo;
case kCondLE: return ls;
case kCondGT: return hi;
case kCondGE: return hs;
// Unsigned remain unchanged.
case kCondB: return lo;
case kCondBE: return ls;
case kCondA: return hi;
case kCondAE: return hs;
}
LOG(FATAL) << "Unreachable";
UNREACHABLE();
}
inline vixl32::Condition ARMFPCondition(IfCondition cond, bool gt_bias) {
// The ARM condition codes can express all the necessary branches, see the
// "Meaning (floating-point)" column in the table A8-1 of the ARMv7 reference manual.
// There is no dex instruction or HIR that would need the missing conditions
// "equal or unordered" or "not equal".
switch (cond) {
case kCondEQ: return eq;
case kCondNE: return ne /* unordered */;
case kCondLT: return gt_bias ? cc : lt /* unordered */;
case kCondLE: return gt_bias ? ls : le /* unordered */;
case kCondGT: return gt_bias ? hi /* unordered */ : gt;
case kCondGE: return gt_bias ? cs /* unordered */ : ge;
default:
LOG(FATAL) << "UNREACHABLE";
UNREACHABLE();
}
}
inline ShiftType ShiftFromOpKind(HDataProcWithShifterOp::OpKind op_kind) {
switch (op_kind) {
case HDataProcWithShifterOp::kASR: return ShiftType::ASR;
case HDataProcWithShifterOp::kLSL: return ShiftType::LSL;
case HDataProcWithShifterOp::kLSR: return ShiftType::LSR;
default:
LOG(FATAL) << "Unexpected op kind " << op_kind;
UNREACHABLE();
}
}
void CodeGeneratorARMVIXL::DumpCoreRegister(std::ostream& stream, int reg) const {
stream << vixl32::Register(reg);
}
void CodeGeneratorARMVIXL::DumpFloatingPointRegister(std::ostream& stream, int reg) const {
stream << vixl32::SRegister(reg);
}
static uint32_t ComputeSRegisterListMask(const SRegisterList& regs) {
uint32_t mask = 0;
for (uint32_t i = regs.GetFirstSRegister().GetCode();
i <= regs.GetLastSRegister().GetCode();
++i) {
mask |= (1 << i);
}
return mask;
}
// Saves the register in the stack. Returns the size taken on stack.
size_t CodeGeneratorARMVIXL::SaveCoreRegister(size_t stack_index ATTRIBUTE_UNUSED,
uint32_t reg_id ATTRIBUTE_UNUSED) {
TODO_VIXL32(FATAL);
return 0;
}
// Restores the register from the stack. Returns the size taken on stack.
size_t CodeGeneratorARMVIXL::RestoreCoreRegister(size_t stack_index ATTRIBUTE_UNUSED,
uint32_t reg_id ATTRIBUTE_UNUSED) {
TODO_VIXL32(FATAL);
return 0;
}
size_t CodeGeneratorARMVIXL::SaveFloatingPointRegister(size_t stack_index ATTRIBUTE_UNUSED,
uint32_t reg_id ATTRIBUTE_UNUSED) {
TODO_VIXL32(FATAL);
return 0;
}
size_t CodeGeneratorARMVIXL::RestoreFloatingPointRegister(size_t stack_index ATTRIBUTE_UNUSED,
uint32_t reg_id ATTRIBUTE_UNUSED) {
TODO_VIXL32(FATAL);
return 0;
}
static void GenerateDataProcInstruction(HInstruction::InstructionKind kind,
vixl32::Register out,
vixl32::Register first,
const Operand& second,
CodeGeneratorARMVIXL* codegen) {
if (second.IsImmediate() && second.GetImmediate() == 0) {
const Operand in = kind == HInstruction::kAnd
? Operand(0)
: Operand(first);
__ Mov(out, in);
} else {
switch (kind) {
case HInstruction::kAdd:
__ Add(out, first, second);
break;
case HInstruction::kAnd:
__ And(out, first, second);
break;
case HInstruction::kOr:
__ Orr(out, first, second);
break;
case HInstruction::kSub:
__ Sub(out, first, second);
break;
case HInstruction::kXor:
__ Eor(out, first, second);
break;
default:
LOG(FATAL) << "Unexpected instruction kind: " << kind;
UNREACHABLE();
}
}
}
static void GenerateDataProc(HInstruction::InstructionKind kind,
const Location& out,
const Location& first,
const Operand& second_lo,
const Operand& second_hi,
CodeGeneratorARMVIXL* codegen) {
const vixl32::Register first_hi = HighRegisterFrom(first);
const vixl32::Register first_lo = LowRegisterFrom(first);
const vixl32::Register out_hi = HighRegisterFrom(out);
const vixl32::Register out_lo = LowRegisterFrom(out);
if (kind == HInstruction::kAdd) {
__ Adds(out_lo, first_lo, second_lo);
__ Adc(out_hi, first_hi, second_hi);
} else if (kind == HInstruction::kSub) {
__ Subs(out_lo, first_lo, second_lo);
__ Sbc(out_hi, first_hi, second_hi);
} else {
GenerateDataProcInstruction(kind, out_lo, first_lo, second_lo, codegen);
GenerateDataProcInstruction(kind, out_hi, first_hi, second_hi, codegen);
}
}
static Operand GetShifterOperand(vixl32::Register rm, ShiftType shift, uint32_t shift_imm) {
return shift_imm == 0 ? Operand(rm) : Operand(rm, shift, shift_imm);
}
static void GenerateLongDataProc(HDataProcWithShifterOp* instruction,
CodeGeneratorARMVIXL* codegen) {
DCHECK_EQ(instruction->GetType(), Primitive::kPrimLong);
DCHECK(HDataProcWithShifterOp::IsShiftOp(instruction->GetOpKind()));
const LocationSummary* const locations = instruction->GetLocations();
const uint32_t shift_value = instruction->GetShiftAmount();
const HInstruction::InstructionKind kind = instruction->GetInstrKind();
const Location first = locations->InAt(0);
const Location second = locations->InAt(1);
const Location out = locations->Out();
const vixl32::Register first_hi = HighRegisterFrom(first);
const vixl32::Register first_lo = LowRegisterFrom(first);
const vixl32::Register out_hi = HighRegisterFrom(out);
const vixl32::Register out_lo = LowRegisterFrom(out);
const vixl32::Register second_hi = HighRegisterFrom(second);
const vixl32::Register second_lo = LowRegisterFrom(second);
const ShiftType shift = ShiftFromOpKind(instruction->GetOpKind());
if (shift_value >= 32) {
if (shift == ShiftType::LSL) {
GenerateDataProcInstruction(kind,
out_hi,
first_hi,
Operand(second_lo, ShiftType::LSL, shift_value - 32),
codegen);
GenerateDataProcInstruction(kind, out_lo, first_lo, 0, codegen);
} else if (shift == ShiftType::ASR) {
GenerateDataProc(kind,
out,
first,
GetShifterOperand(second_hi, ShiftType::ASR, shift_value - 32),
Operand(second_hi, ShiftType::ASR, 31),
codegen);
} else {
DCHECK_EQ(shift, ShiftType::LSR);
GenerateDataProc(kind,
out,
first,
GetShifterOperand(second_hi, ShiftType::LSR, shift_value - 32),
0,
codegen);
}
} else {
DCHECK_GT(shift_value, 1U);
DCHECK_LT(shift_value, 32U);
UseScratchRegisterScope temps(codegen->GetVIXLAssembler());
if (shift == ShiftType::LSL) {
// We are not doing this for HInstruction::kAdd because the output will require
// Location::kOutputOverlap; not applicable to other cases.
if (kind == HInstruction::kOr || kind == HInstruction::kXor) {
GenerateDataProcInstruction(kind,
out_hi,
first_hi,
Operand(second_hi, ShiftType::LSL, shift_value),
codegen);
GenerateDataProcInstruction(kind,
out_hi,
out_hi,
Operand(second_lo, ShiftType::LSR, 32 - shift_value),
codegen);
GenerateDataProcInstruction(kind,
out_lo,
first_lo,
Operand(second_lo, ShiftType::LSL, shift_value),
codegen);
} else {
const vixl32::Register temp = temps.Acquire();
__ Lsl(temp, second_hi, shift_value);
__ Orr(temp, temp, Operand(second_lo, ShiftType::LSR, 32 - shift_value));
GenerateDataProc(kind,
out,
first,
Operand(second_lo, ShiftType::LSL, shift_value),
temp,
codegen);
}
} else {
DCHECK(shift == ShiftType::ASR || shift == ShiftType::LSR);
// We are not doing this for HInstruction::kAdd because the output will require
// Location::kOutputOverlap; not applicable to other cases.
if (kind == HInstruction::kOr || kind == HInstruction::kXor) {
GenerateDataProcInstruction(kind,
out_lo,
first_lo,
Operand(second_lo, ShiftType::LSR, shift_value),
codegen);
GenerateDataProcInstruction(kind,
out_lo,
out_lo,
Operand(second_hi, ShiftType::LSL, 32 - shift_value),
codegen);
GenerateDataProcInstruction(kind,
out_hi,
first_hi,
Operand(second_hi, shift, shift_value),
codegen);
} else {
const vixl32::Register temp = temps.Acquire();
__ Lsr(temp, second_lo, shift_value);
__ Orr(temp, temp, Operand(second_hi, ShiftType::LSL, 32 - shift_value));
GenerateDataProc(kind,
out,
first,
temp,
Operand(second_hi, shift, shift_value),
codegen);
}
}
}
}
static void GenerateVcmp(HInstruction* instruction, CodeGeneratorARMVIXL* codegen) {
const Location rhs_loc = instruction->GetLocations()->InAt(1);
if (rhs_loc.IsConstant()) {
// 0.0 is the only immediate that can be encoded directly in
// a VCMP instruction.
//
// Both the JLS (section 15.20.1) and the JVMS (section 6.5)
// specify that in a floating-point comparison, positive zero
// and negative zero are considered equal, so we can use the
// literal 0.0 for both cases here.
//
// Note however that some methods (Float.equal, Float.compare,
// Float.compareTo, Double.equal, Double.compare,
// Double.compareTo, Math.max, Math.min, StrictMath.max,
// StrictMath.min) consider 0.0 to be (strictly) greater than
// -0.0. So if we ever translate calls to these methods into a
// HCompare instruction, we must handle the -0.0 case with
// care here.
DCHECK(rhs_loc.GetConstant()->IsArithmeticZero());
const Primitive::Type type = instruction->InputAt(0)->GetType();
if (type == Primitive::kPrimFloat) {
__ Vcmp(F32, InputSRegisterAt(instruction, 0), 0.0);
} else {
DCHECK_EQ(type, Primitive::kPrimDouble);
__ Vcmp(F64, InputDRegisterAt(instruction, 0), 0.0);
}
} else {
__ Vcmp(InputVRegisterAt(instruction, 0), InputVRegisterAt(instruction, 1));
}
}
static int64_t AdjustConstantForCondition(int64_t value,
IfCondition* condition,
IfCondition* opposite) {
if (value == 1) {
if (*condition == kCondB) {
value = 0;
*condition = kCondEQ;
*opposite = kCondNE;
} else if (*condition == kCondAE) {
value = 0;
*condition = kCondNE;
*opposite = kCondEQ;
}
} else if (value == -1) {
if (*condition == kCondGT) {
value = 0;
*condition = kCondGE;
*opposite = kCondLT;
} else if (*condition == kCondLE) {
value = 0;
*condition = kCondLT;
*opposite = kCondGE;
}
}
return value;
}
static std::pair<vixl32::Condition, vixl32::Condition> GenerateLongTestConstant(
HCondition* condition,
bool invert,
CodeGeneratorARMVIXL* codegen) {
DCHECK_EQ(condition->GetLeft()->GetType(), Primitive::kPrimLong);
const LocationSummary* const locations = condition->GetLocations();
IfCondition cond = condition->GetCondition();
IfCondition opposite = condition->GetOppositeCondition();
if (invert) {
std::swap(cond, opposite);
}
std::pair<vixl32::Condition, vixl32::Condition> ret(eq, ne);
const Location left = locations->InAt(0);
const Location right = locations->InAt(1);
DCHECK(right.IsConstant());
const vixl32::Register left_high = HighRegisterFrom(left);
const vixl32::Register left_low = LowRegisterFrom(left);
int64_t value = AdjustConstantForCondition(Int64ConstantFrom(right), &cond, &opposite);
UseScratchRegisterScope temps(codegen->GetVIXLAssembler());
// Comparisons against 0 are common enough to deserve special attention.
if (value == 0) {
switch (cond) {
case kCondNE:
// x > 0 iff x != 0 when the comparison is unsigned.
case kCondA:
ret = std::make_pair(ne, eq);
FALLTHROUGH_INTENDED;
case kCondEQ:
// x <= 0 iff x == 0 when the comparison is unsigned.
case kCondBE:
__ Orrs(temps.Acquire(), left_low, left_high);
return ret;
case kCondLT:
case kCondGE:
__ Cmp(left_high, 0);
return std::make_pair(ARMCondition(cond), ARMCondition(opposite));
// Trivially true or false.
case kCondB:
ret = std::make_pair(ne, eq);
FALLTHROUGH_INTENDED;
case kCondAE:
__ Cmp(left_low, left_low);
return ret;
default:
break;
}
}
switch (cond) {
case kCondEQ:
case kCondNE:
case kCondB:
case kCondBE:
case kCondA:
case kCondAE: {
__ Cmp(left_high, High32Bits(value));
// We use the scope because of the IT block that follows.
ExactAssemblyScope guard(codegen->GetVIXLAssembler(),
2 * vixl32::k16BitT32InstructionSizeInBytes,
CodeBufferCheckScope::kExactSize);
__ it(eq);
__ cmp(eq, left_low, Low32Bits(value));
ret = std::make_pair(ARMUnsignedCondition(cond), ARMUnsignedCondition(opposite));
break;
}
case kCondLE:
case kCondGT:
// Trivially true or false.
if (value == std::numeric_limits<int64_t>::max()) {
__ Cmp(left_low, left_low);
ret = cond == kCondLE ? std::make_pair(eq, ne) : std::make_pair(ne, eq);
break;
}
if (cond == kCondLE) {
DCHECK_EQ(opposite, kCondGT);
cond = kCondLT;
opposite = kCondGE;
} else {
DCHECK_EQ(cond, kCondGT);
DCHECK_EQ(opposite, kCondLE);
cond = kCondGE;
opposite = kCondLT;
}
value++;
FALLTHROUGH_INTENDED;
case kCondGE:
case kCondLT: {
__ Cmp(left_low, Low32Bits(value));
__ Sbcs(temps.Acquire(), left_high, High32Bits(value));
ret = std::make_pair(ARMCondition(cond), ARMCondition(opposite));
break;
}
default:
LOG(FATAL) << "Unreachable";
UNREACHABLE();
}
return ret;
}
static std::pair<vixl32::Condition, vixl32::Condition> GenerateLongTest(
HCondition* condition,
bool invert,
CodeGeneratorARMVIXL* codegen) {
DCHECK_EQ(condition->GetLeft()->GetType(), Primitive::kPrimLong);
const LocationSummary* const locations = condition->GetLocations();
IfCondition cond = condition->GetCondition();
IfCondition opposite = condition->GetOppositeCondition();
if (invert) {
std::swap(cond, opposite);
}
std::pair<vixl32::Condition, vixl32::Condition> ret(eq, ne);
Location left = locations->InAt(0);
Location right = locations->InAt(1);
DCHECK(right.IsRegisterPair());
switch (cond) {
case kCondEQ:
case kCondNE:
case kCondB:
case kCondBE:
case kCondA:
case kCondAE: {
__ Cmp(HighRegisterFrom(left), HighRegisterFrom(right));
// We use the scope because of the IT block that follows.
ExactAssemblyScope guard(codegen->GetVIXLAssembler(),
2 * vixl32::k16BitT32InstructionSizeInBytes,
CodeBufferCheckScope::kExactSize);
__ it(eq);
__ cmp(eq, LowRegisterFrom(left), LowRegisterFrom(right));
ret = std::make_pair(ARMUnsignedCondition(cond), ARMUnsignedCondition(opposite));
break;
}
case kCondLE:
case kCondGT:
if (cond == kCondLE) {
DCHECK_EQ(opposite, kCondGT);
cond = kCondGE;
opposite = kCondLT;
} else {
DCHECK_EQ(cond, kCondGT);
DCHECK_EQ(opposite, kCondLE);
cond = kCondLT;
opposite = kCondGE;
}
std::swap(left, right);
FALLTHROUGH_INTENDED;
case kCondGE:
case kCondLT: {
UseScratchRegisterScope temps(codegen->GetVIXLAssembler());
__ Cmp(LowRegisterFrom(left), LowRegisterFrom(right));
__ Sbcs(temps.Acquire(), HighRegisterFrom(left), HighRegisterFrom(right));
ret = std::make_pair(ARMCondition(cond), ARMCondition(opposite));
break;
}
default:
LOG(FATAL) << "Unreachable";
UNREACHABLE();
}
return ret;
}
static std::pair<vixl32::Condition, vixl32::Condition> GenerateTest(HCondition* condition,
bool invert,
CodeGeneratorARMVIXL* codegen) {
const Primitive::Type type = condition->GetLeft()->GetType();
IfCondition cond = condition->GetCondition();
IfCondition opposite = condition->GetOppositeCondition();
std::pair<vixl32::Condition, vixl32::Condition> ret(eq, ne);
if (invert) {
std::swap(cond, opposite);
}
if (type == Primitive::kPrimLong) {
ret = condition->GetLocations()->InAt(1).IsConstant()
? GenerateLongTestConstant(condition, invert, codegen)
: GenerateLongTest(condition, invert, codegen);
} else if (Primitive::IsFloatingPointType(type)) {
GenerateVcmp(condition, codegen);
__ Vmrs(RegisterOrAPSR_nzcv(kPcCode), FPSCR);
ret = std::make_pair(ARMFPCondition(cond, condition->IsGtBias()),
ARMFPCondition(opposite, condition->IsGtBias()));
} else {
DCHECK(Primitive::IsIntegralType(type) || type == Primitive::kPrimNot) << type;
__ Cmp(InputRegisterAt(condition, 0), InputOperandAt(condition, 1));
ret = std::make_pair(ARMCondition(cond), ARMCondition(opposite));
}
return ret;
}
static bool CanGenerateTest(HCondition* condition, ArmVIXLAssembler* assembler) {
if (condition->GetLeft()->GetType() == Primitive::kPrimLong) {
const LocationSummary* const locations = condition->GetLocations();
if (locations->InAt(1).IsConstant()) {
IfCondition c = condition->GetCondition();
IfCondition opposite = condition->GetOppositeCondition();
const int64_t value =
AdjustConstantForCondition(Int64ConstantFrom(locations->InAt(1)), &c, &opposite);
if (c < kCondLT || c > kCondGE) {
// Since IT blocks longer than a 16-bit instruction are deprecated by ARMv8,
// we check that the least significant half of the first input to be compared
// is in a low register (the other half is read outside an IT block), and
// the constant fits in an 8-bit unsigned integer, so that a 16-bit CMP
// encoding can be used; 0 is always handled, no matter what registers are
// used by the first input.
if (value != 0 &&
(!LowRegisterFrom(locations->InAt(0)).IsLow() || !IsUint<8>(Low32Bits(value)))) {
return false;
}
// TODO(VIXL): The rest of the checks are there to keep the backend in sync with
// the previous one, but are not strictly necessary.
} else if (c == kCondLE || c == kCondGT) {
if (value < std::numeric_limits<int64_t>::max() &&
!assembler->ShifterOperandCanHold(SBC, High32Bits(value + 1), kCcSet)) {
return false;
}
} else if (!assembler->ShifterOperandCanHold(SBC, High32Bits(value), kCcSet)) {
return false;
}
}
}
return true;
}
static void GenerateConditionGeneric(HCondition* cond, CodeGeneratorARMVIXL* codegen) {
DCHECK(CanGenerateTest(cond, codegen->GetAssembler()));
const vixl32::Register out = OutputRegister(cond);
const auto condition = GenerateTest(cond, false, codegen);
__ Mov(LeaveFlags, out, 0);
if (out.IsLow()) {
// We use the scope because of the IT block that follows.
ExactAssemblyScope guard(codegen->GetVIXLAssembler(),
2 * vixl32::k16BitT32InstructionSizeInBytes,
CodeBufferCheckScope::kExactSize);
__ it(condition.first);
__ mov(condition.first, out, 1);
} else {
vixl32::Label done_label;
vixl32::Label* const final_label = codegen->GetFinalLabel(cond, &done_label);
__ B(condition.second, final_label, /* far_target */ false);
__ Mov(out, 1);
if (done_label.IsReferenced()) {
__ Bind(&done_label);
}
}
}
static void GenerateEqualLong(HCondition* cond, CodeGeneratorARMVIXL* codegen) {
DCHECK_EQ(cond->GetLeft()->GetType(), Primitive::kPrimLong);
const LocationSummary* const locations = cond->GetLocations();
IfCondition condition = cond->GetCondition();
const vixl32::Register out = OutputRegister(cond);
const Location left = locations->InAt(0);
const Location right = locations->InAt(1);
vixl32::Register left_high = HighRegisterFrom(left);
vixl32::Register left_low = LowRegisterFrom(left);
vixl32::Register temp;
UseScratchRegisterScope temps(codegen->GetVIXLAssembler());
if (right.IsConstant()) {
IfCondition opposite = cond->GetOppositeCondition();
const int64_t value = AdjustConstantForCondition(Int64ConstantFrom(right),
&condition,
&opposite);
Operand right_high = High32Bits(value);
Operand right_low = Low32Bits(value);
// The output uses Location::kNoOutputOverlap.
if (out.Is(left_high)) {
std::swap(left_low, left_high);
std::swap(right_low, right_high);
}
__ Sub(out, left_low, right_low);
temp = temps.Acquire();
__ Sub(temp, left_high, right_high);
} else {
DCHECK(right.IsRegisterPair());
temp = temps.Acquire();
__ Sub(temp, left_high, HighRegisterFrom(right));
__ Sub(out, left_low, LowRegisterFrom(right));
}
// Need to check after calling AdjustConstantForCondition().
DCHECK(condition == kCondEQ || condition == kCondNE) << condition;
if (condition == kCondNE && out.IsLow()) {
__ Orrs(out, out, temp);
// We use the scope because of the IT block that follows.
ExactAssemblyScope guard(codegen->GetVIXLAssembler(),
2 * vixl32::k16BitT32InstructionSizeInBytes,
CodeBufferCheckScope::kExactSize);
__ it(ne);
__ mov(ne, out, 1);
} else {
__ Orr(out, out, temp);
codegen->GenerateConditionWithZero(condition, out, out, temp);
}
}
static void GenerateLongComparesAndJumps(HCondition* cond,
vixl32::Label* true_label,
vixl32::Label* false_label,
CodeGeneratorARMVIXL* codegen,
bool is_far_target = true) {
LocationSummary* locations = cond->GetLocations();
Location left = locations->InAt(0);
Location right = locations->InAt(1);
IfCondition if_cond = cond->GetCondition();
vixl32::Register left_high = HighRegisterFrom(left);
vixl32::Register left_low = LowRegisterFrom(left);
IfCondition true_high_cond = if_cond;
IfCondition false_high_cond = cond->GetOppositeCondition();
vixl32::Condition final_condition = ARMUnsignedCondition(if_cond); // unsigned on lower part
// Set the conditions for the test, remembering that == needs to be
// decided using the low words.
switch (if_cond) {
case kCondEQ:
case kCondNE:
// Nothing to do.
break;
case kCondLT:
false_high_cond = kCondGT;
break;
case kCondLE:
true_high_cond = kCondLT;
break;
case kCondGT:
false_high_cond = kCondLT;
break;
case kCondGE:
true_high_cond = kCondGT;
break;
case kCondB:
false_high_cond = kCondA;
break;
case kCondBE:
true_high_cond = kCondB;
break;
case kCondA:
false_high_cond = kCondB;
break;
case kCondAE:
true_high_cond = kCondA;
break;
}
if (right.IsConstant()) {
int64_t value = Int64ConstantFrom(right);
int32_t val_low = Low32Bits(value);
int32_t val_high = High32Bits(value);
__ Cmp(left_high, val_high);
if (if_cond == kCondNE) {
__ B(ARMCondition(true_high_cond), true_label, is_far_target);
} else if (if_cond == kCondEQ) {
__ B(ARMCondition(false_high_cond), false_label, is_far_target);
} else {
__ B(ARMCondition(true_high_cond), true_label, is_far_target);
__ B(ARMCondition(false_high_cond), false_label, is_far_target);
}
// Must be equal high, so compare the lows.
__ Cmp(left_low, val_low);
} else {
vixl32::Register right_high = HighRegisterFrom(right);
vixl32::Register right_low = LowRegisterFrom(right);
__ Cmp(left_high, right_high);
if (if_cond == kCondNE) {
__ B(ARMCondition(true_high_cond), true_label, is_far_target);
} else if (if_cond == kCondEQ) {
__ B(ARMCondition(false_high_cond), false_label, is_far_target);
} else {
__ B(ARMCondition(true_high_cond), true_label, is_far_target);
__ B(ARMCondition(false_high_cond), false_label, is_far_target);
}
// Must be equal high, so compare the lows.
__ Cmp(left_low, right_low);
}
// The last comparison might be unsigned.
// TODO: optimize cases where this is always true/false
__ B(final_condition, true_label, is_far_target);
}
static void GenerateConditionLong(HCondition* cond, CodeGeneratorARMVIXL* codegen) {
DCHECK_EQ(cond->GetLeft()->GetType(), Primitive::kPrimLong);
const LocationSummary* const locations = cond->GetLocations();
IfCondition condition = cond->GetCondition();
const vixl32::Register out = OutputRegister(cond);
const Location left = locations->InAt(0);
const Location right = locations->InAt(1);
if (right.IsConstant()) {
IfCondition opposite = cond->GetOppositeCondition();
// Comparisons against 0 are common enough to deserve special attention.
if (AdjustConstantForCondition(Int64ConstantFrom(right), &condition, &opposite) == 0) {
switch (condition) {
case kCondNE:
case kCondA:
if (out.IsLow()) {
// We only care if both input registers are 0 or not.
__ Orrs(out, LowRegisterFrom(left), HighRegisterFrom(left));
// We use the scope because of the IT block that follows.
ExactAssemblyScope guard(codegen->GetVIXLAssembler(),
2 * vixl32::k16BitT32InstructionSizeInBytes,
CodeBufferCheckScope::kExactSize);
__ it(ne);
__ mov(ne, out, 1);
return;
}
FALLTHROUGH_INTENDED;
case kCondEQ:
case kCondBE:
// We only care if both input registers are 0 or not.
__ Orr(out, LowRegisterFrom(left), HighRegisterFrom(left));
codegen->GenerateConditionWithZero(condition, out, out);
return;
case kCondLT:
case kCondGE:
// We only care about the sign bit.
FALLTHROUGH_INTENDED;
case kCondAE:
case kCondB:
codegen->GenerateConditionWithZero(condition, out, HighRegisterFrom(left));
return;
case kCondLE:
case kCondGT:
default:
break;
}
}
}
if ((condition == kCondEQ || condition == kCondNE) &&
// If `out` is a low register, then the GenerateConditionGeneric()
// function generates a shorter code sequence that is still branchless.
(!out.IsLow() || !CanGenerateTest(cond, codegen->GetAssembler()))) {
GenerateEqualLong(cond, codegen);
return;
}
if (CanGenerateTest(cond, codegen->GetAssembler())) {
GenerateConditionGeneric(cond, codegen);
return;
}
// Convert the jumps into the result.
vixl32::Label done_label;
vixl32::Label* const final_label = codegen->GetFinalLabel(cond, &done_label);
vixl32::Label true_label, false_label;
GenerateLongComparesAndJumps(cond, &true_label, &false_label, codegen, /* is_far_target */ false);
// False case: result = 0.
__ Bind(&false_label);
__ Mov(out, 0);
__ B(final_label);
// True case: result = 1.
__ Bind(&true_label);
__ Mov(out, 1);
if (done_label.IsReferenced()) {
__ Bind(&done_label);
}
}
static void GenerateConditionIntegralOrNonPrimitive(HCondition* cond, CodeGeneratorARMVIXL* codegen) {
const Primitive::Type type = cond->GetLeft()->GetType();
DCHECK(Primitive::IsIntegralType(type) || type == Primitive::kPrimNot) << type;
if (type == Primitive::kPrimLong) {
GenerateConditionLong(cond, codegen);
return;
}
IfCondition condition = cond->GetCondition();
vixl32::Register in = InputRegisterAt(cond, 0);
const vixl32::Register out = OutputRegister(cond);
const Location right = cond->GetLocations()->InAt(1);
int64_t value;
if (right.IsConstant()) {
IfCondition opposite = cond->GetOppositeCondition();
value = AdjustConstantForCondition(Int64ConstantFrom(right), &condition, &opposite);
// Comparisons against 0 are common enough to deserve special attention.
if (value == 0) {
switch (condition) {
case kCondNE:
case kCondA:
if (out.IsLow() && out.Is(in)) {
__ Cmp(out, 0);
// We use the scope because of the IT block that follows.
ExactAssemblyScope guard(codegen->GetVIXLAssembler(),
2 * vixl32::k16BitT32InstructionSizeInBytes,
CodeBufferCheckScope::kExactSize);
__ it(ne);
__ mov(ne, out, 1);
return;
}
FALLTHROUGH_INTENDED;
case kCondEQ:
case kCondBE:
case kCondLT:
case kCondGE:
case kCondAE:
case kCondB:
codegen->GenerateConditionWithZero(condition, out, in);
return;
case kCondLE:
case kCondGT:
default:
break;
}
}
}
if (condition == kCondEQ || condition == kCondNE) {
Operand operand(0);
if (right.IsConstant()) {
operand = Operand::From(value);
} else if (out.Is(RegisterFrom(right))) {
// Avoid 32-bit instructions if possible.
operand = InputOperandAt(cond, 0);
in = RegisterFrom(right);
} else {
operand = InputOperandAt(cond, 1);
}
if (condition == kCondNE && out.IsLow()) {
__ Subs(out, in, operand);
// We use the scope because of the IT block that follows.
ExactAssemblyScope guard(codegen->GetVIXLAssembler(),
2 * vixl32::k16BitT32InstructionSizeInBytes,
CodeBufferCheckScope::kExactSize);
__ it(ne);
__ mov(ne, out, 1);
} else {
__ Sub(out, in, operand);
codegen->GenerateConditionWithZero(condition, out, out);
}
return;
}
GenerateConditionGeneric(cond, codegen);
}
static bool CanEncodeConstantAs8BitImmediate(HConstant* constant) {
const Primitive::Type type = constant->GetType();
bool ret = false;
DCHECK(Primitive::IsIntegralType(type) || type == Primitive::kPrimNot) << type;
if (type == Primitive::kPrimLong) {
const uint64_t value = Uint64ConstantFrom(constant);
ret = IsUint<8>(Low32Bits(value)) && IsUint<8>(High32Bits(value));
} else {
ret = IsUint<8>(Int32ConstantFrom(constant));
}
return ret;
}
static Location Arm8BitEncodableConstantOrRegister(HInstruction* constant) {
DCHECK(!Primitive::IsFloatingPointType(constant->GetType()));
if (constant->IsConstant() && CanEncodeConstantAs8BitImmediate(constant->AsConstant())) {
return Location::ConstantLocation(constant->AsConstant());
}
return Location::RequiresRegister();
}
static bool CanGenerateConditionalMove(const Location& out, const Location& src) {
// Since IT blocks longer than a 16-bit instruction are deprecated by ARMv8,
// we check that we are not dealing with floating-point output (there is no
// 16-bit VMOV encoding).
if (!out.IsRegister() && !out.IsRegisterPair()) {
return false;
}
// For constants, we also check that the output is in one or two low registers,
// and that the constants fit in an 8-bit unsigned integer, so that a 16-bit
// MOV encoding can be used.
if (src.IsConstant()) {
if (!CanEncodeConstantAs8BitImmediate(src.GetConstant())) {
return false;
}
if (out.IsRegister()) {
if (!RegisterFrom(out).IsLow()) {
return false;
}
} else {
DCHECK(out.IsRegisterPair());
if (!HighRegisterFrom(out).IsLow()) {
return false;
}
}
}
return true;
}
#undef __
vixl32::Label* CodeGeneratorARMVIXL::GetFinalLabel(HInstruction* instruction,
vixl32::Label* final_label) {
DCHECK(!instruction->IsControlFlow() && !instruction->IsSuspendCheck());
DCHECK(!instruction->IsInvoke() || !instruction->GetLocations()->CanCall());
const HBasicBlock* const block = instruction->GetBlock();
const HLoopInformation* const info = block->GetLoopInformation();
HInstruction* const next = instruction->GetNext();
// Avoid a branch to a branch.
if (next->IsGoto() && (info == nullptr ||
!info->IsBackEdge(*block) ||
!info->HasSuspendCheck())) {
final_label = GetLabelOf(next->AsGoto()->GetSuccessor());
}
return final_label;
}
CodeGeneratorARMVIXL::CodeGeneratorARMVIXL(HGraph* graph,
const ArmInstructionSetFeatures& isa_features,
const CompilerOptions& compiler_options,
OptimizingCompilerStats* stats)
: CodeGenerator(graph,
kNumberOfCoreRegisters,
kNumberOfSRegisters,
kNumberOfRegisterPairs,
kCoreCalleeSaves.GetList(),
ComputeSRegisterListMask(kFpuCalleeSaves),
compiler_options,
stats),
block_labels_(graph->GetArena()->Adapter(kArenaAllocCodeGenerator)),
jump_tables_(graph->GetArena()->Adapter(kArenaAllocCodeGenerator)),
location_builder_(graph, this),
instruction_visitor_(graph, this),
move_resolver_(graph->GetArena(), this),
assembler_(graph->GetArena()),
isa_features_(isa_features),
uint32_literals_(std::less<uint32_t>(),
graph->GetArena()->Adapter(kArenaAllocCodeGenerator)),
pc_relative_method_patches_(graph->GetArena()->Adapter(kArenaAllocCodeGenerator)),
method_bss_entry_patches_(graph->GetArena()->Adapter(kArenaAllocCodeGenerator)),
pc_relative_type_patches_(graph->GetArena()->Adapter(kArenaAllocCodeGenerator)),
type_bss_entry_patches_(graph->GetArena()->Adapter(kArenaAllocCodeGenerator)),
pc_relative_string_patches_(graph->GetArena()->Adapter(kArenaAllocCodeGenerator)),
baker_read_barrier_patches_(graph->GetArena()->Adapter(kArenaAllocCodeGenerator)),
jit_string_patches_(StringReferenceValueComparator(),
graph->GetArena()->Adapter(kArenaAllocCodeGenerator)),
jit_class_patches_(TypeReferenceValueComparator(),
graph->GetArena()->Adapter(kArenaAllocCodeGenerator)) {
// Always save the LR register to mimic Quick.
AddAllocatedRegister(Location::RegisterLocation(LR));
// Give D30 and D31 as scratch register to VIXL. The register allocator only works on
// S0-S31, which alias to D0-D15.
GetVIXLAssembler()->GetScratchVRegisterList()->Combine(d31);
GetVIXLAssembler()->GetScratchVRegisterList()->Combine(d30);
}
void JumpTableARMVIXL::EmitTable(CodeGeneratorARMVIXL* codegen) {
uint32_t num_entries = switch_instr_->GetNumEntries();
DCHECK_GE(num_entries, kPackedSwitchCompareJumpThreshold);
// We are about to use the assembler to place literals directly. Make sure we have enough
// underlying code buffer and we have generated a jump table of the right size, using
// codegen->GetVIXLAssembler()->GetBuffer().Align();
ExactAssemblyScope aas(codegen->GetVIXLAssembler(),
num_entries * sizeof(int32_t),
CodeBufferCheckScope::kMaximumSize);
// TODO(VIXL): Check that using lower case bind is fine here.
codegen->GetVIXLAssembler()->bind(&table_start_);
for (uint32_t i = 0; i < num_entries; i++) {
codegen->GetVIXLAssembler()->place(bb_addresses_[i].get());
}
}
void JumpTableARMVIXL::FixTable(CodeGeneratorARMVIXL* codegen) {
uint32_t num_entries = switch_instr_->GetNumEntries();
DCHECK_GE(num_entries, kPackedSwitchCompareJumpThreshold);
const ArenaVector<HBasicBlock*>& successors = switch_instr_->GetBlock()->GetSuccessors();
for (uint32_t i = 0; i < num_entries; i++) {
vixl32::Label* target_label = codegen->GetLabelOf(successors[i]);
DCHECK(target_label->IsBound());
int32_t jump_offset = target_label->GetLocation() - table_start_.GetLocation();
// When doing BX to address we need to have lower bit set to 1 in T32.
if (codegen->GetVIXLAssembler()->IsUsingT32()) {
jump_offset++;
}
DCHECK_GT(jump_offset, std::numeric_limits<int32_t>::min());
DCHECK_LE(jump_offset, std::numeric_limits<int32_t>::max());
bb_addresses_[i].get()->UpdateValue(jump_offset, codegen->GetVIXLAssembler()->GetBuffer());
}
}
void CodeGeneratorARMVIXL::FixJumpTables() {
for (auto&& jump_table : jump_tables_) {
jump_table->FixTable(this);
}
}
#define __ reinterpret_cast<ArmVIXLAssembler*>(GetAssembler())->GetVIXLAssembler()-> // NOLINT
void CodeGeneratorARMVIXL::Finalize(CodeAllocator* allocator) {
FixJumpTables();
GetAssembler()->FinalizeCode();
CodeGenerator::Finalize(allocator);
}
void CodeGeneratorARMVIXL::SetupBlockedRegisters() const {
// Stack register, LR and PC are always reserved.
blocked_core_registers_[SP] = true;
blocked_core_registers_[LR] = true;
blocked_core_registers_[PC] = true;
// Reserve thread register.
blocked_core_registers_[TR] = true;
// Reserve temp register.
blocked_core_registers_[IP] = true;
if (GetGraph()->IsDebuggable()) {
// Stubs do not save callee-save floating point registers. If the graph
// is debuggable, we need to deal with these registers differently. For
// now, just block them.
for (uint32_t i = kFpuCalleeSaves.GetFirstSRegister().GetCode();
i <= kFpuCalleeSaves.GetLastSRegister().GetCode();
++i) {
blocked_fpu_registers_[i] = true;
}
}
}
InstructionCodeGeneratorARMVIXL::InstructionCodeGeneratorARMVIXL(HGraph* graph,
CodeGeneratorARMVIXL* codegen)
: InstructionCodeGenerator(graph, codegen),
assembler_(codegen->GetAssembler()),
codegen_(codegen) {}
void CodeGeneratorARMVIXL::ComputeSpillMask() {
core_spill_mask_ = allocated_registers_.GetCoreRegisters() & core_callee_save_mask_;
DCHECK_NE(core_spill_mask_, 0u) << "At least the return address register must be saved";
// There is no easy instruction to restore just the PC on thumb2. We spill and
// restore another arbitrary register.
core_spill_mask_ |= (1 << kCoreAlwaysSpillRegister.GetCode());
fpu_spill_mask_ = allocated_registers_.GetFloatingPointRegisters() & fpu_callee_save_mask_;
// We use vpush and vpop for saving and restoring floating point registers, which take
// a SRegister and the number of registers to save/restore after that SRegister. We
// therefore update the `fpu_spill_mask_` to also contain those registers not allocated,
// but in the range.
if (fpu_spill_mask_ != 0) {
uint32_t least_significant_bit = LeastSignificantBit(fpu_spill_mask_);
uint32_t most_significant_bit = MostSignificantBit(fpu_spill_mask_);
for (uint32_t i = least_significant_bit + 1 ; i < most_significant_bit; ++i) {
fpu_spill_mask_ |= (1 << i);
}
}
}
void CodeGeneratorARMVIXL::GenerateFrameEntry() {
bool skip_overflow_check =
IsLeafMethod() && !FrameNeedsStackCheck(GetFrameSize(), InstructionSet::kArm);
DCHECK(GetCompilerOptions().GetImplicitStackOverflowChecks());
__ Bind(&frame_entry_label_);
if (HasEmptyFrame()) {
return;
}
if (!skip_overflow_check) {
UseScratchRegisterScope temps(GetVIXLAssembler());
vixl32::Register temp = temps.Acquire();
__ Sub(temp, sp, Operand::From(GetStackOverflowReservedBytes(kArm)));
// The load must immediately precede RecordPcInfo.
ExactAssemblyScope aas(GetVIXLAssembler(),
vixl32::kMaxInstructionSizeInBytes,
CodeBufferCheckScope::kMaximumSize);
__ ldr(temp, MemOperand(temp));
RecordPcInfo(nullptr, 0);
}
__ Push(RegisterList(core_spill_mask_));
GetAssembler()->cfi().AdjustCFAOffset(kArmWordSize * POPCOUNT(core_spill_mask_));
GetAssembler()->cfi().RelOffsetForMany(DWARFReg(kMethodRegister),
0,
core_spill_mask_,
kArmWordSize);
if (fpu_spill_mask_ != 0) {
uint32_t first = LeastSignificantBit(fpu_spill_mask_);
// Check that list is contiguous.
DCHECK_EQ(fpu_spill_mask_ >> CTZ(fpu_spill_mask_), ~0u >> (32 - POPCOUNT(fpu_spill_mask_)));
__ Vpush(SRegisterList(vixl32::SRegister(first), POPCOUNT(fpu_spill_mask_)));
GetAssembler()->cfi().AdjustCFAOffset(kArmWordSize * POPCOUNT(fpu_spill_mask_));
GetAssembler()->cfi().RelOffsetForMany(DWARFReg(s0), 0, fpu_spill_mask_, kArmWordSize);
}
int adjust = GetFrameSize() - FrameEntrySpillSize();
__ Sub(sp, sp, adjust);
GetAssembler()->cfi().AdjustCFAOffset(adjust);
// Save the current method if we need it. Note that we do not
// do this in HCurrentMethod, as the instruction might have been removed
// in the SSA graph.
if (RequiresCurrentMethod()) {
GetAssembler()->StoreToOffset(kStoreWord, kMethodRegister, sp, 0);
}
if (GetGraph()->HasShouldDeoptimizeFlag()) {
UseScratchRegisterScope temps(GetVIXLAssembler());
vixl32::Register temp = temps.Acquire();
// Initialize should_deoptimize flag to 0.
__ Mov(temp, 0);
GetAssembler()->StoreToOffset(kStoreWord, temp, sp, GetStackOffsetOfShouldDeoptimizeFlag());
}
}
void CodeGeneratorARMVIXL::GenerateFrameExit() {
if (HasEmptyFrame()) {
__ Bx(lr);
return;
}
GetAssembler()->cfi().RememberState();
int adjust = GetFrameSize() - FrameEntrySpillSize();
__ Add(sp, sp, adjust);
GetAssembler()->cfi().AdjustCFAOffset(-adjust);
if (fpu_spill_mask_ != 0) {
uint32_t first = LeastSignificantBit(fpu_spill_mask_);
// Check that list is contiguous.
DCHECK_EQ(fpu_spill_mask_ >> CTZ(fpu_spill_mask_), ~0u >> (32 - POPCOUNT(fpu_spill_mask_)));
__ Vpop(SRegisterList(vixl32::SRegister(first), POPCOUNT(fpu_spill_mask_)));
GetAssembler()->cfi().AdjustCFAOffset(
-static_cast<int>(kArmWordSize) * POPCOUNT(fpu_spill_mask_));
GetAssembler()->cfi().RestoreMany(DWARFReg(vixl32::SRegister(0)), fpu_spill_mask_);
}
// Pop LR into PC to return.
DCHECK_NE(core_spill_mask_ & (1 << kLrCode), 0U);
uint32_t pop_mask = (core_spill_mask_ & (~(1 << kLrCode))) | 1 << kPcCode;
__ Pop(RegisterList(pop_mask));
GetAssembler()->cfi().RestoreState();
GetAssembler()->cfi().DefCFAOffset(GetFrameSize());
}
void CodeGeneratorARMVIXL::Bind(HBasicBlock* block) {
__ Bind(GetLabelOf(block));
}
Location InvokeDexCallingConventionVisitorARMVIXL::GetNextLocation(Primitive::Type type) {
switch (type) {
case Primitive::kPrimBoolean:
case Primitive::kPrimByte:
case Primitive::kPrimChar:
case Primitive::kPrimShort:
case Primitive::kPrimInt:
case Primitive::kPrimNot: {
uint32_t index = gp_index_++;
uint32_t stack_index = stack_index_++;
if (index < calling_convention.GetNumberOfRegisters()) {
return LocationFrom(calling_convention.GetRegisterAt(index));
} else {
return Location::StackSlot(calling_convention.GetStackOffsetOf(stack_index));
}
}
case Primitive::kPrimLong: {
uint32_t index = gp_index_;
uint32_t stack_index = stack_index_;
gp_index_ += 2;
stack_index_ += 2;
if (index + 1 < calling_convention.GetNumberOfRegisters()) {
if (calling_convention.GetRegisterAt(index).Is(r1)) {
// Skip R1, and use R2_R3 instead.
gp_index_++;
index++;
}
}
if (index + 1 < calling_convention.GetNumberOfRegisters()) {
DCHECK_EQ(calling_convention.GetRegisterAt(index).GetCode() + 1,
calling_convention.GetRegisterAt(index + 1).GetCode());
return LocationFrom(calling_convention.GetRegisterAt(index),
calling_convention.GetRegisterAt(index + 1));
} else {
return Location::DoubleStackSlot(calling_convention.GetStackOffsetOf(stack_index));
}
}
case Primitive::kPrimFloat: {
uint32_t stack_index = stack_index_++;
if (float_index_ % 2 == 0) {
float_index_ = std::max(double_index_, float_index_);
}
if (float_index_ < calling_convention.GetNumberOfFpuRegisters()) {
return LocationFrom(calling_convention.GetFpuRegisterAt(float_index_++));
} else {
return Location::StackSlot(calling_convention.GetStackOffsetOf(stack_index));
}
}
case Primitive::kPrimDouble: {
double_index_ = std::max(double_index_, RoundUp(float_index_, 2));
uint32_t stack_index = stack_index_;
stack_index_ += 2;
if (double_index_ + 1 < calling_convention.GetNumberOfFpuRegisters()) {
uint32_t index = double_index_;
double_index_ += 2;
Location result = LocationFrom(
calling_convention.GetFpuRegisterAt(index),
calling_convention.GetFpuRegisterAt(index + 1));
DCHECK(ExpectedPairLayout(result));
return result;
} else {
return Location::DoubleStackSlot(calling_convention.GetStackOffsetOf(stack_index));
}
}
case Primitive::kPrimVoid:
LOG(FATAL) << "Unexpected parameter type " << type;
break;
}
return Location::NoLocation();
}
Location InvokeDexCallingConventionVisitorARMVIXL::GetReturnLocation(Primitive::Type type) const {
switch (type) {
case Primitive::kPrimBoolean:
case Primitive::kPrimByte:
case Primitive::kPrimChar:
case Primitive::kPrimShort:
case Primitive::kPrimInt:
case Primitive::kPrimNot: {
return LocationFrom(r0);
}
case Primitive::kPrimFloat: {
return LocationFrom(s0);
}
case Primitive::kPrimLong: {
return LocationFrom(r0, r1);
}
case Primitive::kPrimDouble: {
return LocationFrom(s0, s1);
}
case Primitive::kPrimVoid:
return Location::NoLocation();
}
UNREACHABLE();
}
Location InvokeDexCallingConventionVisitorARMVIXL::GetMethodLocation() const {
return LocationFrom(kMethodRegister);
}
void CodeGeneratorARMVIXL::Move32(Location destination, Location source) {
if (source.Equals(destination)) {
return;
}
if (destination.IsRegister()) {
if (source.IsRegister()) {
__ Mov(RegisterFrom(destination), RegisterFrom(source));
} else if (source.IsFpuRegister()) {
__ Vmov(RegisterFrom(destination), SRegisterFrom(source));
} else {
GetAssembler()->LoadFromOffset(kLoadWord,
RegisterFrom(destination),
sp,
source.GetStackIndex());
}
} else if (destination.IsFpuRegister()) {
if (source.IsRegister()) {
__ Vmov(SRegisterFrom(destination), RegisterFrom(source));
} else if (source.IsFpuRegister()) {
__ Vmov(SRegisterFrom(destination), SRegisterFrom(source));
} else {
GetAssembler()->LoadSFromOffset(SRegisterFrom(destination), sp, source.GetStackIndex());
}
} else {
DCHECK(destination.IsStackSlot()) << destination;
if (source.IsRegister()) {
GetAssembler()->StoreToOffset(kStoreWord,
RegisterFrom(source),
sp,
destination.GetStackIndex());
} else if (source.IsFpuRegister()) {
GetAssembler()->StoreSToOffset(SRegisterFrom(source), sp, destination.GetStackIndex());
} else {
DCHECK(source.IsStackSlot()) << source;
UseScratchRegisterScope temps(GetVIXLAssembler());
vixl32::Register temp = temps.Acquire();
GetAssembler()->LoadFromOffset(kLoadWord, temp, sp, source.GetStackIndex());
GetAssembler()->StoreToOffset(kStoreWord, temp, sp, destination.GetStackIndex());
}
}
}
void CodeGeneratorARMVIXL::MoveConstant(Location location, int32_t value) {
DCHECK(location.IsRegister());
__ Mov(RegisterFrom(location), value);
}
void CodeGeneratorARMVIXL::MoveLocation(Location dst, Location src, Primitive::Type dst_type) {
// TODO(VIXL): Maybe refactor to have the 'move' implementation here and use it in
// `ParallelMoveResolverARMVIXL::EmitMove`, as is done in the `arm64` backend.
HParallelMove move(GetGraph()->GetArena());
move.AddMove(src, dst, dst_type, nullptr);
GetMoveResolver()->EmitNativeCode(&move);
}
void CodeGeneratorARMVIXL::AddLocationAsTemp(Location location, LocationSummary* locations) {
if (location.IsRegister()) {
locations->AddTemp(location);
} else if (location.IsRegisterPair()) {
locations->AddTemp(LocationFrom(LowRegisterFrom(location)));
locations->AddTemp(LocationFrom(HighRegisterFrom(location)));
} else {
UNIMPLEMENTED(FATAL) << "AddLocationAsTemp not implemented for location " << location;
}
}
void CodeGeneratorARMVIXL::InvokeRuntime(QuickEntrypointEnum entrypoint,
HInstruction* instruction,
uint32_t dex_pc,
SlowPathCode* slow_path) {
ValidateInvokeRuntime(entrypoint, instruction, slow_path);
__ Ldr(lr, MemOperand(tr, GetThreadOffset<kArmPointerSize>(entrypoint).Int32Value()));
// Ensure the pc position is recorded immediately after the `blx` instruction.
// blx in T32 has only 16bit encoding that's why a stricter check for the scope is used.
ExactAssemblyScope aas(GetVIXLAssembler(),
vixl32::k16BitT32InstructionSizeInBytes,
CodeBufferCheckScope::kExactSize);
__ blx(lr);
if (EntrypointRequiresStackMap(entrypoint)) {
RecordPcInfo(instruction, dex_pc, slow_path);
}
}
void CodeGeneratorARMVIXL::InvokeRuntimeWithoutRecordingPcInfo(int32_t entry_point_offset,
HInstruction* instruction,
SlowPathCode* slow_path) {
ValidateInvokeRuntimeWithoutRecordingPcInfo(instruction, slow_path);
__ Ldr(lr, MemOperand(tr, entry_point_offset));
__ Blx(lr);
}
void InstructionCodeGeneratorARMVIXL::HandleGoto(HInstruction* got, HBasicBlock* successor) {
DCHECK(!successor->IsExitBlock());
HBasicBlock* block = got->GetBlock();
HInstruction* previous = got->GetPrevious();
HLoopInformation* info = block->GetLoopInformation();
if (info != nullptr && info->IsBackEdge(*block) && info->HasSuspendCheck()) {
codegen_->ClearSpillSlotsFromLoopPhisInStackMap(info->GetSuspendCheck());
GenerateSuspendCheck(info->GetSuspendCheck(), successor);
return;
}
if (block->IsEntryBlock() && (previous != nullptr) && previous->IsSuspendCheck()) {
GenerateSuspendCheck(previous->AsSuspendCheck(), nullptr);
}
if (!codegen_->GoesToNextBlock(block, successor)) {
__ B(codegen_->GetLabelOf(successor));
}
}
void LocationsBuilderARMVIXL::VisitGoto(HGoto* got) {
got->SetLocations(nullptr);
}
void InstructionCodeGeneratorARMVIXL::VisitGoto(HGoto* got) {
HandleGoto(got, got->GetSuccessor());
}
void LocationsBuilderARMVIXL::VisitTryBoundary(HTryBoundary* try_boundary) {
try_boundary->SetLocations(nullptr);
}
void InstructionCodeGeneratorARMVIXL::VisitTryBoundary(HTryBoundary* try_boundary) {
HBasicBlock* successor = try_boundary->GetNormalFlowSuccessor();
if (!successor->IsExitBlock()) {
HandleGoto(try_boundary, successor);
}
}
void LocationsBuilderARMVIXL::VisitExit(HExit* exit) {
exit->SetLocations(nullptr);
}
void InstructionCodeGeneratorARMVIXL::VisitExit(HExit* exit ATTRIBUTE_UNUSED) {
}
void InstructionCodeGeneratorARMVIXL::GenerateCompareTestAndBranch(HCondition* condition,
vixl32::Label* true_target_in,
vixl32::Label* false_target_in,
bool is_far_target) {
if (CanGenerateTest(condition, codegen_->GetAssembler())) {
vixl32::Label* non_fallthrough_target;
bool invert;
bool emit_both_branches;
if (true_target_in == nullptr) {
// The true target is fallthrough.
DCHECK(false_target_in != nullptr);
non_fallthrough_target = false_target_in;
invert = true;
emit_both_branches = false;
} else {
non_fallthrough_target = true_target_in;
invert = false;
// Either the false target is fallthrough, or there is no fallthrough
// and both branches must be emitted.
emit_both_branches = (false_target_in != nullptr);
}
const auto cond = GenerateTest(condition, invert, codegen_);
__ B(cond.first, non_fallthrough_target, is_far_target);
if (emit_both_branches) {
// No target falls through, we need to branch.
__ B(false_target_in);
}
return;
}
// Generated branching requires both targets to be explicit. If either of the
// targets is nullptr (fallthrough) use and bind `fallthrough` instead.
vixl32::Label fallthrough;
vixl32::Label* true_target = (true_target_in == nullptr) ? &fallthrough : true_target_in;
vixl32::Label* false_target = (false_target_in == nullptr) ? &fallthrough : false_target_in;
DCHECK_EQ(condition->InputAt(0)->GetType(), Primitive::kPrimLong);
GenerateLongComparesAndJumps(condition, true_target, false_target, codegen_, is_far_target);
if (false_target != &fallthrough) {
__ B(false_target);
}
if (fallthrough.IsReferenced()) {
__ Bind(&fallthrough);
}
}
void InstructionCodeGeneratorARMVIXL::GenerateTestAndBranch(HInstruction* instruction,
size_t condition_input_index,
vixl32::Label* true_target,
vixl32::Label* false_target,
bool far_target) {
HInstruction* cond = instruction->InputAt(condition_input_index);
if (true_target == nullptr && false_target == nullptr) {
// Nothing to do. The code always falls through.
return;
} else if (cond->IsIntConstant()) {
// Constant condition, statically compared against "true" (integer value 1).
if (cond->AsIntConstant()->IsTrue()) {
if (true_target != nullptr) {
__ B(true_target);
}
} else {
DCHECK(cond->AsIntConstant()->IsFalse()) << Int32ConstantFrom(cond);
if (false_target != nullptr) {
__ B(false_target);
}
}
return;
}
// The following code generates these patterns:
// (1) true_target == nullptr && false_target != nullptr
// - opposite condition true => branch to false_target
// (2) true_target != nullptr && false_target == nullptr
// - condition true => branch to true_target
// (3) true_target != nullptr && false_target != nullptr
// - condition true => branch to true_target
// - branch to false_target
if (IsBooleanValueOrMaterializedCondition(cond)) {
// Condition has been materialized, compare the output to 0.
if (kIsDebugBuild) {
Location cond_val = instruction->GetLocations()->InAt(condition_input_index);
DCHECK(cond_val.IsRegister());
}
if (true_target == nullptr) {
__ CompareAndBranchIfZero(InputRegisterAt(instruction, condition_input_index),
false_target,
far_target);
} else {
__ CompareAndBranchIfNonZero(InputRegisterAt(instruction, condition_input_index),
true_target,
far_target);
}
} else {
// Condition has not been materialized. Use its inputs as the comparison and
// its condition as the branch condition.
HCondition* condition = cond->AsCondition();
// If this is a long or FP comparison that has been folded into
// the HCondition, generate the comparison directly.
Primitive::Type type = condition->InputAt(0)->GetType();
if (type == Primitive::kPrimLong || Primitive::IsFloatingPointType(type)) {
GenerateCompareTestAndBranch(condition, true_target, false_target, far_target);
return;
}
vixl32::Label* non_fallthrough_target;
vixl32::Condition arm_cond = vixl32::Condition::None();
const vixl32::Register left = InputRegisterAt(cond, 0);
const Operand right = InputOperandAt(cond, 1);
if (true_target == nullptr) {
arm_cond = ARMCondition(condition->GetOppositeCondition());
non_fallthrough_target = false_target;
} else {
arm_cond = ARMCondition(condition->GetCondition());
non_fallthrough_target = true_target;
}
if (right.IsImmediate() && right.GetImmediate() == 0 && (arm_cond.Is(ne) || arm_cond.Is(eq))) {
if (arm_cond.Is(eq)) {
__ CompareAndBranchIfZero(left, non_fallthrough_target, far_target);
} else {
DCHECK(arm_cond.Is(ne));
__ CompareAndBranchIfNonZero(left, non_fallthrough_target, far_target);
}
} else {
__ Cmp(left, right);
__ B(arm_cond, non_fallthrough_target, far_target);
}
}
// If neither branch falls through (case 3), the conditional branch to `true_target`
// was already emitted (case 2) and we need to emit a jump to `false_target`.
if (true_target != nullptr && false_target != nullptr) {
__ B(false_target);
}
}
void LocationsBuilderARMVIXL::VisitIf(HIf* if_instr) {
LocationSummary* locations = new (GetGraph()->GetArena()) LocationSummary(if_instr);
if (IsBooleanValueOrMaterializedCondition(if_instr->InputAt(0))) {
locations->SetInAt(0, Location::RequiresRegister());
}
}
void InstructionCodeGeneratorARMVIXL::VisitIf(HIf* if_instr) {
HBasicBlock* true_successor = if_instr->IfTrueSuccessor();
HBasicBlock* false_successor = if_instr->IfFalseSuccessor();
vixl32::Label* true_target = codegen_->GoesToNextBlock(if_instr->GetBlock(), true_successor) ?
nullptr : codegen_->GetLabelOf(true_successor);
vixl32::Label* false_target = codegen_->GoesToNextBlock(if_instr->GetBlock(), false_successor) ?
nullptr : codegen_->GetLabelOf(false_successor);
GenerateTestAndBranch(if_instr, /* condition_input_index */ 0, true_target, false_target);
}
void LocationsBuilderARMVIXL::VisitDeoptimize(HDeoptimize* deoptimize) {
LocationSummary* locations = new (GetGraph()->GetArena())
LocationSummary(deoptimize, LocationSummary::kCallOnSlowPath);
InvokeRuntimeCallingConventionARMVIXL calling_convention;
RegisterSet caller_saves = RegisterSet::Empty();
caller_saves.Add(LocationFrom(calling_convention.GetRegisterAt(0)));
locations->SetCustomSlowPathCallerSaves(caller_saves);
if (IsBooleanValueOrMaterializedCondition(deoptimize->InputAt(0))) {
locations->SetInAt(0, Location::RequiresRegister());
}
}
void InstructionCodeGeneratorARMVIXL::VisitDeoptimize(HDeoptimize* deoptimize) {
SlowPathCodeARMVIXL* slow_path =
deopt_slow_paths_.NewSlowPath<DeoptimizationSlowPathARMVIXL>(deoptimize);
GenerateTestAndBranch(deoptimize,
/* condition_input_index */ 0,
slow_path->GetEntryLabel(),
/* false_target */ nullptr);
}
void LocationsBuilderARMVIXL::VisitShouldDeoptimizeFlag(HShouldDeoptimizeFlag* flag) {
LocationSummary* locations = new (GetGraph()->GetArena())
LocationSummary(flag, LocationSummary::kNoCall);
locations->SetOut(Location::RequiresRegister());
}
void InstructionCodeGeneratorARMVIXL::VisitShouldDeoptimizeFlag(HShouldDeoptimizeFlag* flag) {
GetAssembler()->LoadFromOffset(kLoadWord,
OutputRegister(flag),
sp,
codegen_->GetStackOffsetOfShouldDeoptimizeFlag());
}
void LocationsBuilderARMVIXL::VisitSelect(HSelect* select) {
LocationSummary* locations = new (GetGraph()->GetArena()) LocationSummary(select);
const bool is_floating_point = Primitive::IsFloatingPointType(select->GetType());
if (is_floating_point) {
locations->SetInAt(0, Location::RequiresFpuRegister());
locations->SetInAt(1, Location::FpuRegisterOrConstant(select->GetTrueValue()));
} else {
locations->SetInAt(0, Location::RequiresRegister());
locations->SetInAt(1, Arm8BitEncodableConstantOrRegister(select->GetTrueValue()));
}
if (IsBooleanValueOrMaterializedCondition(select->GetCondition())) {
locations->SetInAt(2, Location::RegisterOrConstant(select->GetCondition()));
// The code generator handles overlap with the values, but not with the condition.
locations->SetOut(Location::SameAsFirstInput());
} else if (is_floating_point) {
locations->SetOut(Location::RequiresFpuRegister(), Location::kNoOutputOverlap);
} else {
if (!locations->InAt(1).IsConstant()) {
locations->SetInAt(0, Arm8BitEncodableConstantOrRegister(select->GetFalseValue()));
}
locations->SetOut(Location::RequiresRegister(), Location::kNoOutputOverlap);
}
}
void InstructionCodeGeneratorARMVIXL::VisitSelect(HSelect* select) {
HInstruction* const condition = select->GetCondition();
const LocationSummary* const locations = select->GetLocations();
const Primitive::Type type = select->GetType();
const Location first = locations->InAt(0);
const Location out = locations->Out();
const Location second = locations->InAt(1);
Location src;
if (condition->IsIntConstant()) {
if (condition->AsIntConstant()->IsFalse()) {
src = first;
} else {
src = second;
}
codegen_->MoveLocation(out, src, type);
return;
}
if (!Primitive::IsFloatingPointType(type) &&
(IsBooleanValueOrMaterializedCondition(condition) ||
CanGenerateTest(condition->AsCondition(), codegen_->GetAssembler()))) {
bool invert = false;
if (out.Equals(second)) {
src = first;
invert = true;
} else if (out.Equals(first)) {
src = second;
} else if (second.IsConstant()) {
DCHECK(CanEncodeConstantAs8BitImmediate(second.GetConstant()));
src = second;
} else if (first.IsConstant()) {
DCHECK(CanEncodeConstantAs8BitImmediate(first.GetConstant()));
src = first;
invert = true;
} else {
src = second;
}
if (CanGenerateConditionalMove(out, src)) {
if (!out.Equals(first) && !out.Equals(second)) {
codegen_->MoveLocation(out, src.Equals(first) ? second : first, type);
}
std::pair<vixl32::Condition, vixl32::Condition> cond(eq, ne);
if (IsBooleanValueOrMaterializedCondition(condition)) {
__ Cmp(InputRegisterAt(select, 2), 0);
cond = invert ? std::make_pair(eq, ne) : std::make_pair(ne, eq);
} else {
cond = GenerateTest(condition->AsCondition(), invert, codegen_);
}
const size_t instr_count = out.IsRegisterPair() ? 4 : 2;
// We use the scope because of the IT block that follows.
ExactAssemblyScope guard(GetVIXLAssembler(),
instr_count * vixl32::k16BitT32InstructionSizeInBytes,
CodeBufferCheckScope::kExactSize);
if (out.IsRegister()) {
__ it(cond.first);
__ mov(cond.first, RegisterFrom(out), OperandFrom(src, type));
} else {
DCHECK(out.IsRegisterPair());
Operand operand_high(0);
Operand operand_low(0);
if (src.IsConstant()) {
const int64_t value = Int64ConstantFrom(src);
operand_high = High32Bits(value);
operand_low = Low32Bits(value);
} else {
DCHECK(src.IsRegisterPair());
operand_high = HighRegisterFrom(src);
operand_low = LowRegisterFrom(src);
}
__ it(cond.first);
__ mov(cond.first, LowRegisterFrom(out), operand_low);
__ it(cond.first);
__ mov(cond.first, HighRegisterFrom(out), operand_high);
}
return;
}
}
vixl32::Label* false_target = nullptr;
vixl32::Label* true_target = nullptr;
vixl32::Label select_end;
vixl32::Label* const target = codegen_->GetFinalLabel(select, &select_end);
if (out.Equals(second)) {
true_target = target;
src = first;
} else {
false_target = target;
src = second;
if (!out.Equals(first)) {
codegen_->MoveLocation(out, first, type);
}
}
GenerateTestAndBranch(select, 2, true_target, false_target, /* far_target */ false);
codegen_->MoveLocation(out, src, type);
if (select_end.IsReferenced()) {
__ Bind(&select_end);
}
}
void LocationsBuilderARMVIXL::VisitNativeDebugInfo(HNativeDebugInfo* info) {
new (GetGraph()->GetArena()) LocationSummary(info);
}
void InstructionCodeGeneratorARMVIXL::VisitNativeDebugInfo(HNativeDebugInfo*) {
// MaybeRecordNativeDebugInfo is already called implicitly in CodeGenerator::Compile.
}
void CodeGeneratorARMVIXL::GenerateNop() {
__ Nop();
}
// `temp` is an extra temporary register that is used for some conditions;
// callers may not specify it, in which case the method will use a scratch
// register instead.
void CodeGeneratorARMVIXL::GenerateConditionWithZero(IfCondition condition,
vixl32::Register out,
vixl32::Register in,
vixl32::Register temp) {
switch (condition) {
case kCondEQ:
// x <= 0 iff x == 0 when the comparison is unsigned.
case kCondBE:
if (!temp.IsValid() || (out.IsLow() && !out.Is(in))) {
temp = out;
}
// Avoid 32-bit instructions if possible; note that `in` and `temp` must be
// different as well.
if (in.IsLow() && temp.IsLow() && !in.Is(temp)) {
// temp = - in; only 0 sets the carry flag.
__ Rsbs(temp, in, 0);
if (out.Is(in)) {
std::swap(in, temp);
}
// out = - in + in + carry = carry
__ Adc(out, temp, in);
} else {
// If `in` is 0, then it has 32 leading zeros, and less than that otherwise.
__ Clz(out, in);
// Any number less than 32 logically shifted right by 5 bits results in 0;
// the same operation on 32 yields 1.
__ Lsr(out, out, 5);
}
break;
case kCondNE:
// x > 0 iff x != 0 when the comparison is unsigned.
case kCondA: {
UseScratchRegisterScope temps(GetVIXLAssembler());
if (out.Is(in)) {
if (!temp.IsValid() || in.Is(temp)) {
temp = temps.Acquire();
}
} else if (!temp.IsValid() || !temp.IsLow()) {
temp = out;
}
// temp = in - 1; only 0 does not set the carry flag.
__ Subs(temp, in, 1);
// out = in + ~temp + carry = in + (-(in - 1) - 1) + carry = in - in + 1 - 1 + carry = carry
__ Sbc(out, in, temp);
break;
}
case kCondGE:
__ Mvn(out, in);
in = out;
FALLTHROUGH_INTENDED;
case kCondLT:
// We only care about the sign bit.
__ Lsr(out, in, 31);
break;
case kCondAE:
// Trivially true.
__ Mov(out, 1);
break;
case kCondB:
// Trivially false.
__ Mov(out, 0);
break;
default:
LOG(FATAL) << "Unexpected condition " << condition;
UNREACHABLE();
}
}
void LocationsBuilderARMVIXL::HandleCondition(HCondition* cond) {
LocationSummary* locations =
new (GetGraph()->GetArena()) LocationSummary(cond, LocationSummary::kNoCall);
// Handle the long/FP comparisons made in instruction simplification.
switch (cond->InputAt(0)->GetType()) {
case Primitive::kPrimLong:
locations->SetInAt(0, Location::RequiresRegister());
locations->SetInAt(1, Location::RegisterOrConstant(cond->InputAt(1)));
if (!cond->IsEmittedAtUseSite()) {
locations->SetOut(Location::RequiresRegister(), Location::kNoOutputOverlap);
}
break;
case Primitive::kPrimFloat:
case Primitive::kPrimDouble:
locations->SetInAt(0, Location::RequiresFpuRegister());
locations->SetInAt(1, ArithmeticZeroOrFpuRegister(cond->InputAt(1)));
if (!cond->IsEmittedAtUseSite()) {
locations->SetOut(Location::RequiresRegister(), Location::kNoOutputOverlap);
}
break;
default:
locations->SetInAt(0, Location::RequiresRegister());
locations->SetInAt(1, Location::RegisterOrConstant(cond->InputAt(1)));
if (!cond->IsEmittedAtUseSite()) {
locations->SetOut(Location::RequiresRegister(), Location::kNoOutputOverlap);
}
}
}
void InstructionCodeGeneratorARMVIXL::HandleCondition(HCondition* cond) {
if (cond->IsEmittedAtUseSite()) {
return;
}
const Primitive::Type type = cond->GetLeft()->GetType();
if (Primitive::IsFloatingPointType(type)) {
GenerateConditionGeneric(cond, codegen_);
return;
}
DCHECK(Primitive::IsIntegralType(type) || type == Primitive::kPrimNot) << type;
const IfCondition condition = cond->GetCondition();
// A condition with only one boolean input, or two boolean inputs without being equality or
// inequality results from transformations done by the instruction simplifier, and is handled
// as a regular condition with integral inputs.
if (type == Primitive::kPrimBoolean &&
cond->GetRight()->GetType() == Primitive::kPrimBoolean &&
(condition == kCondEQ || condition == kCondNE)) {
vixl32::Register left = InputRegisterAt(cond, 0);
const vixl32::Register out = OutputRegister(cond);
const Location right_loc = cond->GetLocations()->InAt(1);
// The constant case is handled by the instruction simplifier.
DCHECK(!right_loc.IsConstant());
vixl32::Register right = RegisterFrom(right_loc);
// Avoid 32-bit instructions if possible.
if (out.Is(right)) {
std::swap(left, right);
}
__ Eor(out, left, right);
if (condition == kCondEQ) {
__ Eor(out, out, 1);
}
return;
}
GenerateConditionIntegralOrNonPrimitive(cond, codegen_);
}
void LocationsBuilderARMVIXL::VisitEqual(HEqual* comp) {
HandleCondition(comp);
}
void InstructionCodeGeneratorARMVIXL::VisitEqual(HEqual* comp) {
HandleCondition(comp);
}
void LocationsBuilderARMVIXL::VisitNotEqual(HNotEqual* comp) {
HandleCondition(comp);
}
void InstructionCodeGeneratorARMVIXL::VisitNotEqual(HNotEqual* comp) {
HandleCondition(comp);
}
void LocationsBuilderARMVIXL::VisitLessThan(HLessThan* comp) {
HandleCondition(comp);
}
void InstructionCodeGeneratorARMVIXL::VisitLessThan(HLessThan* comp) {
HandleCondition(comp);
}
void LocationsBuilderARMVIXL::VisitLessThanOrEqual(HLessThanOrEqual* comp) {
HandleCondition(comp);
}
void InstructionCodeGeneratorARMVIXL::VisitLessThanOrEqual(HLessThanOrEqual* comp) {
HandleCondition(comp);
}
void LocationsBuilderARMVIXL::VisitGreaterThan(HGreaterThan* comp) {
HandleCondition(comp);
}
void InstructionCodeGeneratorARMVIXL::VisitGreaterThan(HGreaterThan* comp) {
HandleCondition(comp);
}
void LocationsBuilderARMVIXL::VisitGreaterThanOrEqual(HGreaterThanOrEqual* comp) {
HandleCondition(comp);
}
void InstructionCodeGeneratorARMVIXL::VisitGreaterThanOrEqual(HGreaterThanOrEqual* comp) {
HandleCondition(comp);
}
void LocationsBuilderARMVIXL::VisitBelow(HBelow* comp) {
HandleCondition(comp);
}
void InstructionCodeGeneratorARMVIXL::VisitBelow(HBelow* comp) {
HandleCondition(comp);
}
void LocationsBuilderARMVIXL::VisitBelowOrEqual(HBelowOrEqual* comp) {
HandleCondition(comp);
}
void InstructionCodeGeneratorARMVIXL::VisitBelowOrEqual(HBelowOrEqual* comp) {
HandleCondition(comp);
}
void LocationsBuilderARMVIXL::VisitAbove(HAbove* comp) {
HandleCondition(comp);
}
void InstructionCodeGeneratorARMVIXL::VisitAbove(HAbove* comp) {
HandleCondition(comp);
}
void LocationsBuilderARMVIXL::VisitAboveOrEqual(HAboveOrEqual* comp) {
HandleCondition(comp);
}
void InstructionCodeGeneratorARMVIXL::VisitAboveOrEqual(HAboveOrEqual* comp) {
HandleCondition(comp);
}
void LocationsBuilderARMVIXL::VisitIntConstant(HIntConstant* constant) {
LocationSummary* locations =
new (GetGraph()->GetArena()) LocationSummary(constant, LocationSummary::kNoCall);
locations->SetOut(Location::ConstantLocation(constant));
}
void InstructionCodeGeneratorARMVIXL::VisitIntConstant(HIntConstant* constant ATTRIBUTE_UNUSED) {
// Will be generated at use site.
}
void LocationsBuilderARMVIXL::VisitNullConstant(HNullConstant* constant) {
LocationSummary* locations =
new (GetGraph()->GetArena()) LocationSummary(constant, LocationSummary::kNoCall);
locations->SetOut(Location::ConstantLocation(constant));
}
void InstructionCodeGeneratorARMVIXL::VisitNullConstant(HNullConstant* constant ATTRIBUTE_UNUSED) {
// Will be generated at use site.
}
void LocationsBuilderARMVIXL::VisitLongConstant(HLongConstant* constant) {
LocationSummary* locations =
new (GetGraph()->GetArena()) LocationSummary(constant, LocationSummary::kNoCall);
locations->SetOut(Location::ConstantLocation(constant));
}
void InstructionCodeGeneratorARMVIXL::VisitLongConstant(HLongConstant* constant ATTRIBUTE_UNUSED) {
// Will be generated at use site.
}
void LocationsBuilderARMVIXL::VisitFloatConstant(HFloatConstant* constant) {
LocationSummary* locations =
new (GetGraph()->GetArena()) LocationSummary(constant, LocationSummary::kNoCall);
locations->SetOut(Location::ConstantLocation(constant));
}
void InstructionCodeGeneratorARMVIXL::VisitFloatConstant(
HFloatConstant* constant ATTRIBUTE_UNUSED) {
// Will be generated at use site.
}
void LocationsBuilderARMVIXL::VisitDoubleConstant(HDoubleConstant* constant) {
LocationSummary* locations =
new (GetGraph()->GetArena()) LocationSummary(constant, LocationSummary::kNoCall);
locations->SetOut(Location::ConstantLocation(constant));
}
void InstructionCodeGeneratorARMVIXL::VisitDoubleConstant(
HDoubleConstant* constant ATTRIBUTE_UNUSED) {
// Will be generated at use site.
}
void LocationsBuilderARMVIXL::VisitConstructorFence(HConstructorFence* constructor_fence) {
constructor_fence->SetLocations(nullptr);
}
void InstructionCodeGeneratorARMVIXL::VisitConstructorFence(
HConstructorFence* constructor_fence ATTRIBUTE_UNUSED) {
codegen_->GenerateMemoryBarrier(MemBarrierKind::kStoreStore);
}
void LocationsBuilderARMVIXL::VisitMemoryBarrier(HMemoryBarrier* memory_barrier) {
memory_barrier->SetLocations(nullptr);
}
void InstructionCodeGeneratorARMVIXL::VisitMemoryBarrier(HMemoryBarrier* memory_barrier) {
codegen_->GenerateMemoryBarrier(memory_barrier->GetBarrierKind());
}
void LocationsBuilderARMVIXL::VisitReturnVoid(HReturnVoid* ret) {
ret->SetLocations(nullptr);
}
void InstructionCodeGeneratorARMVIXL::VisitReturnVoid(HReturnVoid* ret ATTRIBUTE_UNUSED) {
codegen_->GenerateFrameExit();
}
void LocationsBuilderARMVIXL::VisitReturn(HReturn* ret) {
LocationSummary* locations =
new (GetGraph()->GetArena()) LocationSummary(ret, LocationSummary::kNoCall);
locations->SetInAt(0, parameter_visitor_.GetReturnLocation(ret->InputAt(0)->GetType()));
}
void InstructionCodeGeneratorARMVIXL::VisitReturn(HReturn* ret ATTRIBUTE_UNUSED) {
codegen_->GenerateFrameExit();
}
void LocationsBuilderARMVIXL::VisitInvokeUnresolved(HInvokeUnresolved* invoke) {
// The trampoline uses the same calling convention as dex calling conventions,
// except instead of loading arg0/r0 with the target Method*, arg0/r0 will contain
// the method_idx.
HandleInvoke(invoke);
}
void InstructionCodeGeneratorARMVIXL::VisitInvokeUnresolved(HInvokeUnresolved* invoke) {
codegen_->GenerateInvokeUnresolvedRuntimeCall(invoke);
}
void LocationsBuilderARMVIXL::VisitInvokeStaticOrDirect(HInvokeStaticOrDirect* invoke) {
// Explicit clinit checks triggered by static invokes must have been pruned by
// art::PrepareForRegisterAllocation.
DCHECK(!invoke->IsStaticWithExplicitClinitCheck());
IntrinsicLocationsBuilderARMVIXL intrinsic(codegen_);
if (intrinsic.TryDispatch(invoke)) {
return;
}
HandleInvoke(invoke);
}
static bool TryGenerateIntrinsicCode(HInvoke* invoke, CodeGeneratorARMVIXL* codegen) {
if (invoke->GetLocations()->Intrinsified()) {
IntrinsicCodeGeneratorARMVIXL intrinsic(codegen);
intrinsic.Dispatch(invoke);
return true;
}
return false;
}
void InstructionCodeGeneratorARMVIXL::VisitInvokeStaticOrDirect(HInvokeStaticOrDirect* invoke) {
// Explicit clinit checks triggered by static invokes must have been pruned by
// art::PrepareForRegisterAllocation.
DCHECK(!invoke->IsStaticWithExplicitClinitCheck());
if (TryGenerateIntrinsicCode(invoke, codegen_)) {
return;
}
LocationSummary* locations = invoke->GetLocations();
codegen_->GenerateStaticOrDirectCall(
invoke, locations->HasTemps() ? locations->GetTemp(0) : Location::NoLocation());
}
void LocationsBuilderARMVIXL::HandleInvoke(HInvoke* invoke) {
InvokeDexCallingConventionVisitorARMVIXL calling_convention_visitor;
CodeGenerator::CreateCommonInvokeLocationSummary(invoke, &calling_convention_visitor);
}
void LocationsBuilderARMVIXL::VisitInvokeVirtual(HInvokeVirtual* invoke) {
IntrinsicLocationsBuilderARMVIXL intrinsic(codegen_);
if (intrinsic.TryDispatch(invoke)) {
return;
}
HandleInvoke(invoke);
}
void InstructionCodeGeneratorARMVIXL::VisitInvokeVirtual(HInvokeVirtual* invoke) {
if (TryGenerateIntrinsicCode(invoke, codegen_)) {
return;
}
codegen_->GenerateVirtualCall(invoke, invoke->GetLocations()->GetTemp(0));
DCHECK(!codegen_->IsLeafMethod());
}
void LocationsBuilderARMVIXL::VisitInvokeInterface(HInvokeInterface* invoke) {
HandleInvoke(invoke);
// Add the hidden argument.
invoke->GetLocations()->AddTemp(LocationFrom(r12));
}
void InstructionCodeGeneratorARMVIXL::VisitInvokeInterface(HInvokeInterface* invoke) {
// TODO: b/18116999, our IMTs can miss an IncompatibleClassChangeError.
LocationSummary* locations = invoke->GetLocations();
vixl32::Register temp = RegisterFrom(locations->GetTemp(0));
vixl32::Register hidden_reg = RegisterFrom(locations->GetTemp(1));
Location receiver = locations->InAt(0);
uint32_t class_offset = mirror::Object::ClassOffset().Int32Value();
DCHECK(!receiver.IsStackSlot());
// Ensure the pc position is recorded immediately after the `ldr` instruction.
{
ExactAssemblyScope aas(GetVIXLAssembler(),
vixl32::kMaxInstructionSizeInBytes,
CodeBufferCheckScope::kMaximumSize);
// /* HeapReference<Class> */ temp = receiver->klass_
__ ldr(temp, MemOperand(RegisterFrom(receiver), class_offset));
codegen_->MaybeRecordImplicitNullCheck(invoke);
}
// Instead of simply (possibly) unpoisoning `temp` here, we should
// emit a read barrier for the previous class reference load.
// However this is not required in practice, as this is an
// intermediate/temporary reference and because the current
// concurrent copying collector keeps the from-space memory
// intact/accessible until the end of the marking phase (the
// concurrent copying collector may not in the future).
GetAssembler()->MaybeUnpoisonHeapReference(temp);
GetAssembler()->LoadFromOffset(kLoadWord,
temp,
temp,
mirror::Class::ImtPtrOffset(kArmPointerSize).Uint32Value());
uint32_t method_offset = static_cast<uint32_t>(ImTable::OffsetOfElement(
invoke->GetImtIndex(), kArmPointerSize));
// temp = temp->GetImtEntryAt(method_offset);
GetAssembler()->LoadFromOffset(kLoadWord, temp, temp, method_offset);
uint32_t entry_point =
ArtMethod::EntryPointFromQuickCompiledCodeOffset(kArmPointerSize).Int32Value();
// LR = temp->GetEntryPoint();
GetAssembler()->LoadFromOffset(kLoadWord, lr, temp, entry_point);
// Set the hidden (in r12) argument. It is done here, right before a BLX to prevent other
// instruction from clobbering it as they might use r12 as a scratch register.
DCHECK(hidden_reg.Is(r12));
{
// The VIXL macro assembler may clobber any of the scratch registers that are available to it,
// so it checks if the application is using them (by passing them to the macro assembler
// methods). The following application of UseScratchRegisterScope corrects VIXL's notion of
// what is available, and is the opposite of the standard usage: Instead of requesting a
// temporary location, it imposes an external constraint (i.e. a specific register is reserved
// for the hidden argument). Note that this works even if VIXL needs a scratch register itself
// (to materialize the constant), since the destination register becomes available for such use
// internally for the duration of the macro instruction.
UseScratchRegisterScope temps(GetVIXLAssembler());
temps.Exclude(hidden_reg);
__ Mov(hidden_reg, invoke->GetDexMethodIndex());
}
{
// Ensure the pc position is recorded immediately after the `blx` instruction.
// blx in T32 has only 16bit encoding that's why a stricter check for the scope is used.
ExactAssemblyScope aas(GetVIXLAssembler(),
vixl32::k16BitT32InstructionSizeInBytes,
CodeBufferCheckScope::kExactSize);
// LR();
__ blx(lr);
codegen_->RecordPcInfo(invoke, invoke->GetDexPc());
DCHECK(!codegen_->IsLeafMethod());
}
}
void LocationsBuilderARMVIXL::VisitInvokePolymorphic(HInvokePolymorphic* invoke) {
HandleInvoke(invoke);
}
void InstructionCodeGeneratorARMVIXL::VisitInvokePolymorphic(HInvokePolymorphic* invoke) {
codegen_->GenerateInvokePolymorphicCall(invoke);
}
void LocationsBuilderARMVIXL::VisitNeg(HNeg* neg) {
LocationSummary* locations =
new (GetGraph()->GetArena()) LocationSummary(neg, LocationSummary::kNoCall);
switch (neg->GetResultType()) {
case Primitive::kPrimInt: {
locations->SetInAt(0, Location::RequiresRegister());
locations->SetOut(Location::RequiresRegister(), Location::kNoOutputOverlap);
break;
}
case Primitive::kPrimLong: {
locations->SetInAt(0, Location::RequiresRegister());
locations->SetOut(Location::RequiresRegister(), Location::kOutputOverlap);
break;
}
case Primitive::kPrimFloat:
case Primitive::kPrimDouble:
locations->SetInAt(0, Location::RequiresFpuRegister());
locations->SetOut(Location::RequiresFpuRegister(), Location::kNoOutputOverlap);
break;
default:
LOG(FATAL) << "Unexpected neg type " << neg->GetResultType();
}
}
void InstructionCodeGeneratorARMVIXL::VisitNeg(HNeg* neg) {
LocationSummary* locations = neg->GetLocations();
Location out = locations->Out();
Location in = locations->InAt(0);
switch (neg->GetResultType()) {
case Primitive::kPrimInt:
__ Rsb(OutputRegister(neg), InputRegisterAt(neg, 0), 0);
break;
case Primitive::kPrimLong:
// out.lo = 0 - in.lo (and update the carry/borrow (C) flag)
__ Rsbs(LowRegisterFrom(out), LowRegisterFrom(in), 0);
// We cannot emit an RSC (Reverse Subtract with Carry)
// instruction here, as it does not exist in the Thumb-2
// instruction set. We use the following approach
// using SBC and SUB instead.
//
// out.hi = -C
__ Sbc(HighRegisterFrom(out), HighRegisterFrom(out), HighRegisterFrom(out));
// out.hi = out.hi - in.hi
__ Sub(HighRegisterFrom(out), HighRegisterFrom(out), HighRegisterFrom(in));
break;
case Primitive::kPrimFloat:
case Primitive::kPrimDouble:
__ Vneg(OutputVRegister(neg), InputVRegister(neg));
break;
default:
LOG(FATAL) << "Unexpected neg type " << neg->GetResultType();
}
}
void LocationsBuilderARMVIXL::VisitTypeConversion(HTypeConversion* conversion) {
Primitive::Type result_type = conversion->GetResultType();
Primitive::Type input_type = conversion->GetInputType();
DCHECK_NE(result_type, input_type);
// The float-to-long, double-to-long and long-to-float type conversions
// rely on a call to the runtime.
LocationSummary::CallKind call_kind =
(((input_type == Primitive::kPrimFloat || input_type == Primitive::kPrimDouble)
&& result_type == Primitive::kPrimLong)
|| (input_type == Primitive::kPrimLong && result_type == Primitive::kPrimFloat))
? LocationSummary::kCallOnMainOnly
: LocationSummary::kNoCall;
LocationSummary* locations =
new (GetGraph()->GetArena()) LocationSummary(conversion, call_kind);
// The Java language does not allow treating boolean as an integral type but
// our bit representation makes it safe.
switch (result_type) {
case Primitive::kPrimByte:
switch (input_type) {
case Primitive::kPrimLong:
// Type conversion from long to byte is a result of code transformations.
case Primitive::kPrimBoolean:
// Boolean input is a result of code transformations.
case Primitive::kPrimShort:
case Primitive::kPrimInt:
case Primitive::kPrimChar:
// Processing a Dex `int-to-byte' instruction.
locations->SetInAt(0, Location::RequiresRegister());
locations->SetOut(Location::RequiresRegister(), Location::kNoOutputOverlap);
break;
default:
LOG(FATAL) << "Unexpected type conversion from " << input_type
<< " to " << result_type;
}
break;
case Primitive::kPrimShort:
switch (input_type) {
case Primitive::kPrimLong:
// Type conversion from long to short is a result of code transformations.
case Primitive::kPrimBoolean:
// Boolean input is a result of code transformations.
case Primitive::kPrimByte:
case Primitive::kPrimInt:
case Primitive::kPrimChar:
// Processing a Dex `int-to-short' instruction.
locations->SetInAt(0, Location::RequiresRegister());
locations->SetOut(Location::RequiresRegister(), Location::kNoOutputOverlap);
break;
default:
LOG(FATAL) << "Unexpected type conversion from " << input_type
<< " to " << result_type;
}
break;
case Primitive::kPrimInt:
switch (input_type) {
case Primitive::kPrimLong:
// Processing a Dex `long-to-int' instruction.
locations->SetInAt(0, Location::Any());
locations->SetOut(Location::RequiresRegister(), Location::kNoOutputOverlap);
break;
case Primitive::kPrimFloat:
// Processing a Dex `float-to-int' instruction.
locations->SetInAt(0, Location::RequiresFpuRegister());
locations->SetOut(Location::RequiresRegister());
locations->AddTemp(Location::RequiresFpuRegister());
break;
case Primitive::kPrimDouble:
// Processing a Dex `double-to-int' instruction.
locations->SetInAt(0, Location::RequiresFpuRegister());
locations->SetOut(Location::RequiresRegister());
locations->AddTemp(Location::RequiresFpuRegister());
break;
default:
LOG(FATAL) << "Unexpected type conversion from " << input_type
<< " to " << result_type;
}
break;
case Primitive::kPrimLong:
switch (input_type) {
case Primitive::kPrimBoolean:
// Boolean input is a result of code transformations.
case Primitive::kPrimByte:
case Primitive::kPrimShort:
case Primitive::kPrimInt:
case Primitive::kPrimChar:
// Processing a Dex `int-to-long' instruction.
locations->SetInAt(0, Location::RequiresRegister());
locations->SetOut(Location::RequiresRegister(), Location::kNoOutputOverlap);
break;
case Primitive::kPrimFloat: {
// Processing a Dex `float-to-long' instruction.
InvokeRuntimeCallingConventionARMVIXL calling_convention;
locations->SetInAt(0, LocationFrom(calling_convention.GetFpuRegisterAt(0)));
locations->SetOut(LocationFrom(r0, r1));
break;
}
case Primitive::kPrimDouble: {
// Processing a Dex `double-to-long' instruction.
InvokeRuntimeCallingConventionARMVIXL calling_convention;
locations->SetInAt(0, LocationFrom(calling_convention.GetFpuRegisterAt(0),
calling_convention.GetFpuRegisterAt(1)));
locations->SetOut(LocationFrom(r0, r1));
break;
}
default:
LOG(FATAL) << "Unexpected type conversion from " << input_type
<< " to " << result_type;
}
break;
case Primitive::kPrimChar:
switch (input_type) {
case Primitive::kPrimLong:
// Type conversion from long to char is a result of code transformations.
case Primitive::kPrimBoolean:
// Boolean input is a result of code transformations.
case Primitive::kPrimByte:
case Primitive::kPrimShort:
case Primitive::kPrimInt:
// Processing a Dex `int-to-char' instruction.
locations->SetInAt(0, Location::RequiresRegister());
locations->SetOut(Location::RequiresRegister(), Location::kNoOutputOverlap);
break;
default:
LOG(FATAL) << "Unexpected type conversion from " << input_type
<< " to " << result_type;
}
break;
case Primitive::kPrimFloat:
switch (input_type) {
case Primitive::kPrimBoolean:
// Boolean input is a result of code transformations.
case Primitive::kPrimByte:
case Primitive::kPrimShort:
case Primitive::kPrimInt:
case Primitive::kPrimChar:
// Processing a Dex `int-to-float' instruction.
locations->SetInAt(0, Location::RequiresRegister());
locations->SetOut(Location::RequiresFpuRegister());
break;
case Primitive::kPrimLong: {
// Processing a Dex `long-to-float' instruction.
InvokeRuntimeCallingConventionARMVIXL calling_convention;
locations->SetInAt(0, LocationFrom(calling_convention.GetRegisterAt(0),
calling_convention.GetRegisterAt(1)));
locations->SetOut(LocationFrom(calling_convention.GetFpuRegisterAt(0)));
break;
}
case Primitive::kPrimDouble:
// Processing a Dex `double-to-float' instruction.
locations->SetInAt(0, Location::RequiresFpuRegister());
locations->SetOut(Location::RequiresFpuRegister(), Location::kNoOutputOverlap);
break;
default:
LOG(FATAL) << "Unexpected type conversion from " << input_type
<< " to " << result_type;
};
break;
case Primitive::kPrimDouble:
switch (input_type) {
case Primitive::kPrimBoolean:
// Boolean input is a result of code transformations.
case Primitive::kPrimByte:
case Primitive::kPrimShort:
case Primitive::kPrimInt:
case Primitive::kPrimChar:
// Processing a Dex `int-to-double' instruction.
locations->SetInAt(0, Location::RequiresRegister());
locations->SetOut(Location::RequiresFpuRegister());
break;
case Primitive::kPrimLong:
// Processing a Dex `long-to-double' instruction.
locations->SetInAt(0, Location::RequiresRegister());
locations->SetOut(Location::RequiresFpuRegister());
locations->AddTemp(Location::RequiresFpuRegister());
locations->AddTemp(Location::RequiresFpuRegister());
break;
case Primitive::kPrimFloat:
// Processing a Dex `float-to-double' instruction.
locations->SetInAt(0, Location::RequiresFpuRegister());
locations->SetOut(Location::RequiresFpuRegister(), Location::kNoOutputOverlap);
break;
default:
LOG(FATAL) << "Unexpected type conversion from " << input_type
<< " to " << result_type;
};
break;
default:
LOG(FATAL) << "Unexpected type conversion from " << input_type
<< " to " << result_type;
}
}
void InstructionCodeGeneratorARMVIXL::VisitTypeConversion(HTypeConversion* conversion) {
LocationSummary* locations = conversion->GetLocations();
Location out = locations->Out();
Location in = locations->InAt(0);
Primitive::Type result_type = conversion->GetResultType();
Primitive::Type input_type = conversion->GetInputType();
DCHECK_NE(result_type, input_type);
switch (result_type) {
case Primitive::kPrimByte:
switch (input_type) {
case Primitive::kPrimLong:
// Type conversion from long to byte is a result of code transformations.
__ Sbfx(OutputRegister(conversion), LowRegisterFrom(in), 0, 8);
break;
case Primitive::kPrimBoolean:
// Boolean input is a result of code transformations.
case Primitive::kPrimShort:
case Primitive::kPrimInt:
case Primitive::kPrimChar:
// Processing a Dex `int-to-byte' instruction.
__ Sbfx(OutputRegister(conversion), InputRegisterAt(conversion, 0), 0, 8);
break;
default:
LOG(FATAL) << "Unexpected type conversion from " << input_type
<< " to " << result_type;
}
break;
case Primitive::kPrimShort:
switch (input_type) {
case Primitive::kPrimLong:
// Type conversion from long to short is a result of code transformations.
__ Sbfx(OutputRegister(conversion), LowRegisterFrom(in), 0, 16);
break;
case Primitive::kPrimBoolean:
// Boolean input is a result of code transformations.
case Primitive::kPrimByte:
case Primitive::kPrimInt:
case Primitive::kPrimChar:
// Processing a Dex `int-to-short' instruction.
__ Sbfx(OutputRegister(conversion), InputRegisterAt(conversion, 0), 0, 16);
break;
default:
LOG(FATAL) << "Unexpected type conversion from " << input_type
<< " to " << result_type;
}
break;
case Primitive::kPrimInt:
switch (input_type) {
case Primitive::kPrimLong:
// Processing a Dex `long-to-int' instruction.
DCHECK(out.IsRegister());
if (in.IsRegisterPair()) {
__ Mov(OutputRegister(conversion), LowRegisterFrom(in));
} else if (in.IsDoubleStackSlot()) {
GetAssembler()->LoadFromOffset(kLoadWord,
OutputRegister(conversion),
sp,
in.GetStackIndex());
} else {
DCHECK(in.IsConstant());
DCHECK(in.GetConstant()->IsLongConstant());
int64_t value = in.GetConstant()->AsLongConstant()->GetValue();
__ Mov(OutputRegister(conversion), static_cast<int32_t>(value));
}
break;
case Primitive::kPrimFloat: {
// Processing a Dex `float-to-int' instruction.
vixl32::SRegister temp = LowSRegisterFrom(locations->GetTemp(0));
__ Vcvt(S32, F32, temp, InputSRegisterAt(conversion, 0));
__ Vmov(OutputRegister(conversion), temp);
break;
}
case Primitive::kPrimDouble: {
// Processing a Dex `double-to-int' instruction.
vixl32::SRegister temp_s = LowSRegisterFrom(locations->GetTemp(0));
__ Vcvt(S32, F64, temp_s, DRegisterFrom(in));
__ Vmov(OutputRegister(conversion), temp_s);
break;
}
default:
LOG(FATAL) << "Unexpected type conversion from " << input_type
<< " to " << result_type;
}
break;
case Primitive::kPrimLong:
switch (input_type) {
case Primitive::kPrimBoolean:
// Boolean input is a result of code transformations.
case Primitive::kPrimByte:
case Primitive::kPrimShort:
case Primitive::kPrimInt:
case Primitive::kPrimChar:
// Processing a Dex `int-to-long' instruction.
DCHECK(out.IsRegisterPair());
DCHECK(in.IsRegister());
__ Mov(LowRegisterFrom(out), InputRegisterAt(conversion, 0));
// Sign extension.
__ Asr(HighRegisterFrom(out), LowRegisterFrom(out), 31);
break;
case Primitive::kPrimFloat:
// Processing a Dex `float-to-long' instruction.
codegen_->InvokeRuntime(kQuickF2l, conversion, conversion->GetDexPc());
CheckEntrypointTypes<kQuickF2l, int64_t, float>();
break;
case Primitive::kPrimDouble:
// Processing a Dex `double-to-long' instruction.
codegen_->InvokeRuntime(kQuickD2l, conversion, conversion->GetDexPc());
CheckEntrypointTypes<kQuickD2l, int64_t, double>();
break;
default:
LOG(FATAL) << "Unexpected type conversion from " << input_type
<< " to " << result_type;
}
break;
case Primitive::kPrimChar:
switch (input_type) {
case Primitive::kPrimLong:
// Type conversion from long to char is a result of code transformations.
__ Ubfx(OutputRegister(conversion), LowRegisterFrom(in), 0, 16);
break;
case Primitive::kPrimBoolean:
// Boolean input is a result of code transformations.
case Primitive::kPrimByte:
case Primitive::kPrimShort:
case Primitive::kPrimInt:
// Processing a Dex `int-to-char' instruction.
__ Ubfx(OutputRegister(conversion), InputRegisterAt(conversion, 0), 0, 16);
break;
default:
LOG(FATAL) << "Unexpected type conversion from " << input_type
<< " to " << result_type;
}
break;
case Primitive::kPrimFloat:
switch (input_type) {
case Primitive::kPrimBoolean:
// Boolean input is a result of code transformations.
case Primitive::kPrimByte:
case Primitive::kPrimShort:
case Primitive::kPrimInt:
case Primitive::kPrimChar: {
// Processing a Dex `int-to-float' instruction.
__ Vmov(OutputSRegister(conversion), InputRegisterAt(conversion, 0));
__ Vcvt(F32, S32, OutputSRegister(conversion), OutputSRegister(conversion));
break;
}
case Primitive::kPrimLong:
// Processing a Dex `long-to-float' instruction.
codegen_->InvokeRuntime(kQuickL2f, conversion, conversion->GetDexPc());
CheckEntrypointTypes<kQuickL2f, float, int64_t>();
break;
case Primitive::kPrimDouble:
// Processing a Dex `double-to-float' instruction.
__ Vcvt(F32, F64, OutputSRegister(conversion), DRegisterFrom(in));
break;
default:
LOG(FATAL) << "Unexpected type conversion from " << input_type
<< " to " << result_type;
};
break;
case Primitive::kPrimDouble:
switch (input_type) {
case Primitive::kPrimBoolean:
// Boolean input is a result of code transformations.
case Primitive::kPrimByte:
case Primitive::kPrimShort:
case Primitive::kPrimInt:
case Primitive::kPrimChar: {
// Processing a Dex `int-to-double' instruction.
__ Vmov(LowSRegisterFrom(out), InputRegisterAt(conversion, 0));
__ Vcvt(F64, S32, DRegisterFrom(out), LowSRegisterFrom(out));
break;
}
case Primitive::kPrimLong: {
// Processing a Dex `long-to-double' instruction.
vixl32::Register low = LowRegisterFrom(in);
vixl32::Register high = HighRegisterFrom(in);
vixl32::SRegister out_s = LowSRegisterFrom(out);
vixl32::DRegister out_d = DRegisterFrom(out);
vixl32::SRegister temp_s = LowSRegisterFrom(locations->GetTemp(0));
vixl32::DRegister temp_d = DRegisterFrom(locations->GetTemp(0));
vixl32::DRegister constant_d = DRegisterFrom(locations->GetTemp(1));
// temp_d = int-to-double(high)
__ Vmov(temp_s, high);
__ Vcvt(F64, S32, temp_d, temp_s);
// constant_d = k2Pow32EncodingForDouble
__ Vmov(constant_d, bit_cast<double, int64_t>(k2Pow32EncodingForDouble));
// out_d = unsigned-to-double(low)
__ Vmov(out_s, low);
__ Vcvt(F64, U32, out_d, out_s);
// out_d += temp_d * constant_d
__ Vmla(F64, out_d, temp_d, constant_d);
break;
}
case Primitive::kPrimFloat:
// Processing a Dex `float-to-double' instruction.
__ Vcvt(F64, F32, DRegisterFrom(out), InputSRegisterAt(conversion, 0));
break;
default:
LOG(FATAL) << "Unexpected type conversion from " << input_type
<< " to " << result_type;
};
break;
default:
LOG(FATAL) << "Unexpected type conversion from " << input_type
<< " to " << result_type;
}
}
void LocationsBuilderARMVIXL::VisitAdd(HAdd* add) {
LocationSummary* locations =
new (GetGraph()->GetArena()) LocationSummary(add, LocationSummary::kNoCall);
switch (add->GetResultType()) {
case Primitive::kPrimInt: {
locations->SetInAt(0, Location::RequiresRegister());
locations->SetInAt(1, Location::RegisterOrConstant(add->InputAt(1)));
locations->SetOut(Location::RequiresRegister(), Location::kNoOutputOverlap);
break;
}
case Primitive::kPrimLong: {
locations->SetInAt(0, Location::RequiresRegister());
locations->SetInAt(1, ArmEncodableConstantOrRegister(add->InputAt(1), ADD));
locations->SetOut(Location::RequiresRegister(), Location::kNoOutputOverlap);
break;
}
case Primitive::kPrimFloat:
case Primitive::kPrimDouble: {
locations->SetInAt(0, Location::RequiresFpuRegister());
locations->SetInAt(1, Location::RequiresFpuRegister());
locations->SetOut(Location::RequiresFpuRegister(), Location::kNoOutputOverlap);
break;
}
default:
LOG(FATAL) << "Unexpected add type " << add->GetResultType();
}
}
void InstructionCodeGeneratorARMVIXL::VisitAdd(HAdd* add) {
LocationSummary* locations = add->GetLocations();
Location out = locations->Out();
Location first = locations->InAt(0);
Location second = locations->InAt(1);
switch (add->GetResultType()) {
case Primitive::kPrimInt: {
__ Add(OutputRegister(add), InputRegisterAt(add, 0), InputOperandAt(add, 1));
}
break;
case Primitive::kPrimLong: {
if (second.IsConstant()) {
uint64_t value = static_cast<uint64_t>(Int64FromConstant(second.GetConstant()));
GenerateAddLongConst(out, first, value);
} else {
DCHECK(second.IsRegisterPair());
__ Adds(LowRegisterFrom(out), LowRegisterFrom(first), LowRegisterFrom(second));
__ Adc(HighRegisterFrom(out), HighRegisterFrom(first), HighRegisterFrom(second));
}
break;
}
case Primitive::kPrimFloat:
case Primitive::kPrimDouble:
__ Vadd(OutputVRegister(add), InputVRegisterAt(add, 0), InputVRegisterAt(add, 1));
break;
default:
LOG(FATAL) << "Unexpected add type " << add->GetResultType();
}
}
void LocationsBuilderARMVIXL::VisitSub(HSub* sub) {
LocationSummary* locations =
new (GetGraph()->GetArena()) LocationSummary(sub, LocationSummary::kNoCall);
switch (sub->GetResultType()) {
case Primitive::kPrimInt: {
locations->SetInAt(0, Location::RequiresRegister());
locations->SetInAt(1, Location::RegisterOrConstant(sub->InputAt(1)));
locations->SetOut(Location::RequiresRegister(), Location::kNoOutputOverlap);
break;
}
case Primitive::kPrimLong: {
locations->SetInAt(0, Location::RequiresRegister());
locations->SetInAt(1, ArmEncodableConstantOrRegister(sub->InputAt(1), SUB));
locations->SetOut(Location::RequiresRegister(), Location::kNoOutputOverlap);
break;
}
case Primitive::kPrimFloat:
case Primitive::kPrimDouble: {
locations->SetInAt(0, Location::RequiresFpuRegister());
locations->SetInAt(1, Location::RequiresFpuRegister());
locations->SetOut(Location::RequiresFpuRegister(), Location::kNoOutputOverlap);
break;
}
default:
LOG(FATAL) << "Unexpected sub type " << sub->GetResultType();
}
}
void InstructionCodeGeneratorARMVIXL::VisitSub(HSub* sub) {
LocationSummary* locations = sub->GetLocations();
Location out = locations->Out();
Location first = locations->InAt(0);
Location second = locations->InAt(1);
switch (sub->GetResultType()) {
case Primitive::kPrimInt: {
__ Sub(OutputRegister(sub), InputRegisterAt(sub, 0), InputOperandAt(sub, 1));
break;
}
case Primitive::kPrimLong: {
if (second.IsConstant()) {
uint64_t value = static_cast<uint64_t>(Int64FromConstant(second.GetConstant()));
GenerateAddLongConst(out, first, -value);
} else {
DCHECK(second.IsRegisterPair());
__ Subs(LowRegisterFrom(out), LowRegisterFrom(first), LowRegisterFrom(second));
__ Sbc(HighRegisterFrom(out), HighRegisterFrom(first), HighRegisterFrom(second));
}
break;
}
case Primitive::kPrimFloat:
case Primitive::kPrimDouble:
__ Vsub(OutputVRegister(sub), InputVRegisterAt(sub, 0), InputVRegisterAt(sub, 1));
break;
default:
LOG(FATAL) << "Unexpected sub type " << sub->GetResultType();
}
}
void LocationsBuilderARMVIXL::VisitMul(HMul* mul) {
LocationSummary* locations =
new (GetGraph()->GetArena()) LocationSummary(mul, LocationSummary::kNoCall);
switch (mul->GetResultType()) {
case Primitive::kPrimInt:
case Primitive::kPrimLong: {
locations->SetInAt(0, Location::RequiresRegister());
locations->SetInAt(1, Location::RequiresRegister());
locations->SetOut(Location::RequiresRegister(), Location::kNoOutputOverlap);
break;
}
case Primitive::kPrimFloat:
case Primitive::kPrimDouble: {
locations->SetInAt(0, Location::RequiresFpuRegister());
locations->SetInAt(1, Location::RequiresFpuRegister());
locations->SetOut(Location::RequiresFpuRegister(), Location::kNoOutputOverlap);
break;
}
default:
LOG(FATAL) << "Unexpected mul type " << mul->GetResultType();
}
}
void InstructionCodeGeneratorARMVIXL::VisitMul(HMul* mul) {
LocationSummary* locations = mul->GetLocations();
Location out = locations->Out();
Location first = locations->InAt(0);
Location second = locations->InAt(1);
switch (mul->GetResultType()) {
case Primitive::kPrimInt: {
__ Mul(OutputRegister(mul), InputRegisterAt(mul, 0), InputRegisterAt(mul, 1));
break;
}
case Primitive::kPrimLong: {
vixl32::Register out_hi = HighRegisterFrom(out);
vixl32::Register out_lo = LowRegisterFrom(out);
vixl32::Register in1_hi = HighRegisterFrom(first);
vixl32::Register in1_lo = LowRegisterFrom(first);
vixl32::Register in2_hi = HighRegisterFrom(second);
vixl32::Register in2_lo = LowRegisterFrom(second);
// Extra checks to protect caused by the existence of R1_R2.
// The algorithm is wrong if out.hi is either in1.lo or in2.lo:
// (e.g. in1=r0_r1, in2=r2_r3 and out=r1_r2);
DCHECK(!out_hi.Is(in1_lo));
DCHECK(!out_hi.Is(in2_lo));
// input: in1 - 64 bits, in2 - 64 bits
// output: out
// formula: out.hi : out.lo = (in1.lo * in2.hi + in1.hi * in2.lo)* 2^32 + in1.lo * in2.lo
// parts: out.hi = in1.lo * in2.hi + in1.hi * in2.lo + (in1.lo * in2.lo)[63:32]
// parts: out.lo = (in1.lo * in2.lo)[31:0]
UseScratchRegisterScope temps(GetVIXLAssembler());
vixl32::Register temp = temps.Acquire();
// temp <- in1.lo * in2.hi
__ Mul(temp, in1_lo, in2_hi);
// out.hi <- in1.lo * in2.hi + in1.hi * in2.lo
__ Mla(out_hi, in1_hi, in2_lo, temp);
// out.lo <- (in1.lo * in2.lo)[31:0];
__ Umull(out_lo, temp, in1_lo, in2_lo);
// out.hi <- in2.hi * in1.lo + in2.lo * in1.hi + (in1.lo * in2.lo)[63:32]
__ Add(out_hi, out_hi, temp);
break;
}
case Primitive::kPrimFloat:
case Primitive::kPrimDouble:
__ Vmul(OutputVRegister(mul), InputVRegisterAt(mul, 0), InputVRegisterAt(mul, 1));
break;
default:
LOG(FATAL) << "Unexpected mul type " << mul->GetResultType();
}
}
void InstructionCodeGeneratorARMVIXL::DivRemOneOrMinusOne(HBinaryOperation* instruction) {
DCHECK(instruction->IsDiv() || instruction->IsRem());
DCHECK(instruction->GetResultType() == Primitive::kPrimInt);
Location second = instruction->GetLocations()->InAt(1);
DCHECK(second.IsConstant());
vixl32::Register out = OutputRegister(instruction);
vixl32::Register dividend = InputRegisterAt(instruction, 0);
int32_t imm = Int32ConstantFrom(second);
DCHECK(imm == 1 || imm == -1);
if (instruction->IsRem()) {
__ Mov(out, 0);
} else {
if (imm == 1) {
__ Mov(out, dividend);
} else {
__ Rsb(out, dividend, 0);
}
}
}
void InstructionCodeGeneratorARMVIXL::DivRemByPowerOfTwo(HBinaryOperation* instruction) {
DCHECK(instruction->IsDiv() || instruction->IsRem());
DCHECK(instruction->GetResultType() == Primitive::kPrimInt);
LocationSummary* locations = instruction->GetLocations();
Location second = locations->InAt(1);
DCHECK(second.IsConstant());
vixl32::Register out = OutputRegister(instruction);
vixl32::Register dividend = InputRegisterAt(instruction, 0);
vixl32::Register temp = RegisterFrom(locations->GetTemp(0));
int32_t imm = Int32ConstantFrom(second);
uint32_t abs_imm = static_cast<uint32_t>(AbsOrMin(imm));
int ctz_imm = CTZ(abs_imm);
if (ctz_imm == 1) {
__ Lsr(temp, dividend, 32 - ctz_imm);
} else {
__ Asr(temp, dividend, 31);
__ Lsr(temp, temp, 32 - ctz_imm);
}
__ Add(out, temp, dividend);
if (instruction->IsDiv()) {
__ Asr(out, out, ctz_imm);
if (imm < 0) {
__ Rsb(out, out, 0);
}
} else {
__ Ubfx(out, out, 0, ctz_imm);
__ Sub(out, out, temp);
}
}
void InstructionCodeGeneratorARMVIXL::GenerateDivRemWithAnyConstant(HBinaryOperation* instruction) {
DCHECK(instruction->IsDiv() || instruction->IsRem());
DCHECK(instruction->GetResultType() == Primitive::kPrimInt);
LocationSummary* locations = instruction->GetLocations();
Location second = locations->InAt(1);
DCHECK(second.IsConstant());
vixl32::Register out = OutputRegister(instruction);
vixl32::Register dividend = InputRegisterAt(instruction, 0);
vixl32::Register temp1 = RegisterFrom(locations->GetTemp(0));
vixl32::Register temp2 = RegisterFrom(locations->GetTemp(1));
int32_t imm = Int32ConstantFrom(second);
int64_t magic;
int shift;
CalculateMagicAndShiftForDivRem(imm, false /* is_long */, &magic, &shift);
// TODO(VIXL): Change the static cast to Operand::From() after VIXL is fixed.
__ Mov(temp1, static_cast<int32_t>(magic));
__ Smull(temp2, temp1, dividend, temp1);
if (imm > 0 && magic < 0) {
__ Add(temp1, temp1, dividend);
} else if (imm < 0 && magic > 0) {
__ Sub(temp1, temp1, dividend);
}
if (shift != 0) {
__ Asr(temp1, temp1, shift);
}
if (instruction->IsDiv()) {
__ Sub(out, temp1, Operand(temp1, vixl32::Shift(ASR), 31));
} else {
__ Sub(temp1, temp1, Operand(temp1, vixl32::Shift(ASR), 31));
// TODO: Strength reduction for mls.
__ Mov(temp2, imm);
__ Mls(out, temp1, temp2, dividend);
}
}
void InstructionCodeGeneratorARMVIXL::GenerateDivRemConstantIntegral(
HBinaryOperation* instruction) {
DCHECK(instruction->IsDiv() || instruction->IsRem());
DCHECK(instruction->GetResultType() == Primitive::kPrimInt);
Location second = instruction->GetLocations()->InAt(1);
DCHECK(second.IsConstant());
int32_t imm = Int32ConstantFrom(second);
if (imm == 0) {
// Do not generate anything. DivZeroCheck would prevent any code to be executed.
} else if (imm == 1 || imm == -1) {
DivRemOneOrMinusOne(instruction);
} else if (IsPowerOfTwo(AbsOrMin(imm))) {
DivRemByPowerOfTwo(instruction);
} else {
DCHECK(imm <= -2 || imm >= 2);
GenerateDivRemWithAnyConstant(instruction);
}
}
void LocationsBuilderARMVIXL::VisitDiv(HDiv* div) {
LocationSummary::CallKind call_kind = LocationSummary::kNoCall;
if (div->GetResultType() == Primitive::kPrimLong) {
// pLdiv runtime call.
call_kind = LocationSummary::kCallOnMainOnly;
} else if (div->GetResultType() == Primitive::kPrimInt && div->InputAt(1)->IsConstant()) {
// sdiv will be replaced by other instruction sequence.
} else if (div->GetResultType() == Primitive::kPrimInt &&
!codegen_->GetInstructionSetFeatures().HasDivideInstruction()) {
// pIdivmod runtime call.
call_kind = LocationSummary::kCallOnMainOnly;
}
LocationSummary* locations = new (GetGraph()->GetArena()) LocationSummary(div, call_kind);
switch (div->GetResultType()) {
case Primitive::kPrimInt: {
if (div->InputAt(1)->IsConstant()) {
locations->SetInAt(0, Location::RequiresRegister());
locations->SetInAt(1, Location::ConstantLocation(div->InputAt(1)->AsConstant()));
locations->SetOut(Location::RequiresRegister(), Location::kNoOutputOverlap);
int32_t value = Int32ConstantFrom(div->InputAt(1));
if (value == 1 || value == 0 || value == -1) {
// No temp register required.
} else {
locations->AddTemp(Location::RequiresRegister());
if (!IsPowerOfTwo(AbsOrMin(value))) {
locations->AddTemp(Location::RequiresRegister());
}
}
} else if (codegen_->GetInstructionSetFeatures().HasDivideInstruction()) {
locations->SetInAt(0, Location::RequiresRegister());
locations->SetInAt(1, Location::RequiresRegister());
locations->SetOut(Location::RequiresRegister(), Location::kNoOutputOverlap);
} else {
InvokeRuntimeCallingConventionARMVIXL calling_convention;
locations->SetInAt(0, LocationFrom(calling_convention.GetRegisterAt(0)));
locations->SetInAt(1, LocationFrom(calling_convention.GetRegisterAt(1)));
// Note: divmod will compute both the quotient and the remainder as the pair R0 and R1, but
// we only need the former.
locations->SetOut(LocationFrom(r0));
}
break;
}
case Primitive::kPrimLong: {
InvokeRuntimeCallingConventionARMVIXL calling_convention;
locations->SetInAt(0, LocationFrom(
calling_convention.GetRegisterAt(0), calling_convention.GetRegisterAt(1)));
locations->SetInAt(1, LocationFrom(
calling_convention.GetRegisterAt(2), calling_convention.GetRegisterAt(3)));
locations->SetOut(LocationFrom(r0, r1));
break;
}
case Primitive::kPrimFloat:
case Primitive::kPrimDouble: {
locations->SetInAt(0, Location::RequiresFpuRegister());
locations->SetInAt(1, Location::RequiresFpuRegister());
locations->SetOut(Location::RequiresFpuRegister(), Location::kNoOutputOverlap);
break;
}
default:
LOG(FATAL) << "Unexpected div type " << div->GetResultType();
}
}
void InstructionCodeGeneratorARMVIXL::VisitDiv(HDiv* div) {
Location lhs = div->GetLocations()->InAt(0);
Location rhs = div->GetLocations()->InAt(1);
switch (div->GetResultType()) {
case Primitive::kPrimInt: {
if (rhs.IsConstant()) {
GenerateDivRemConstantIntegral(div);
} else if (codegen_->GetInstructionSetFeatures().HasDivideInstruction()) {
__ Sdiv(OutputRegister(div), InputRegisterAt(div, 0), InputRegisterAt(div, 1));
} else {
InvokeRuntimeCallingConventionARMVIXL calling_convention;
DCHECK(calling_convention.GetRegisterAt(0).Is(RegisterFrom(lhs)));
DCHECK(calling_convention.GetRegisterAt(1).Is(RegisterFrom(rhs)));
DCHECK(r0.Is(OutputRegister(div)));
codegen_->InvokeRuntime(kQuickIdivmod, div, div->GetDexPc());
CheckEntrypointTypes<kQuickIdivmod, int32_t, int32_t, int32_t>();
}
break;
}
case Primitive::kPrimLong: {
InvokeRuntimeCallingConventionARMVIXL calling_convention;
DCHECK(calling_convention.GetRegisterAt(0).Is(LowRegisterFrom(lhs)));
DCHECK(calling_convention.GetRegisterAt(1).Is(HighRegisterFrom(lhs)));
DCHECK(calling_convention.GetRegisterAt(2).Is(LowRegisterFrom(rhs)));
DCHECK(calling_convention.GetRegisterAt(3).Is(HighRegisterFrom(rhs)));
DCHECK(LowRegisterFrom(div->GetLocations()->Out()).Is(r0));
DCHECK(HighRegisterFrom(div->GetLocations()->Out()).Is(r1));
codegen_->InvokeRuntime(kQuickLdiv, div, div->GetDexPc());
CheckEntrypointTypes<kQuickLdiv, int64_t, int64_t, int64_t>();
break;
}
case Primitive::kPrimFloat:
case Primitive::kPrimDouble:
__ Vdiv(OutputVRegister(div), InputVRegisterAt(div, 0), InputVRegisterAt(div, 1));
break;
default:
LOG(FATAL) << "Unexpected div type " << div->GetResultType();
}
}
void LocationsBuilderARMVIXL::VisitRem(HRem* rem) {
Primitive::Type type = rem->GetResultType();
// Most remainders are implemented in the runtime.
LocationSummary::CallKind call_kind = LocationSummary::kCallOnMainOnly;
if (rem->GetResultType() == Primitive::kPrimInt && rem->InputAt(1)->IsConstant()) {
// sdiv will be replaced by other instruction sequence.
call_kind = LocationSummary::kNoCall;
} else if ((rem->GetResultType() == Primitive::kPrimInt)
&& codegen_->GetInstructionSetFeatures().HasDivideInstruction()) {
// Have hardware divide instruction for int, do it with three instructions.
call_kind = LocationSummary::kNoCall;
}
LocationSummary* locations = new (GetGraph()->GetArena()) LocationSummary(rem, call_kind);
switch (type) {
case Primitive::kPrimInt: {
if (rem->InputAt(1)->IsConstant()) {
locations->SetInAt(0, Location::RequiresRegister());
locations->SetInAt(1, Location::ConstantLocation(rem->InputAt(1)->AsConstant()));
locations->SetOut(Location::RequiresRegister(), Location::kNoOutputOverlap);
int32_t value = Int32ConstantFrom(rem->InputAt(1));
if (value == 1 || value == 0 || value == -1) {
// No temp register required.
} else {
locations->AddTemp(Location::RequiresRegister());
if (!IsPowerOfTwo(AbsOrMin(value))) {
locations->AddTemp(Location::RequiresRegister());
}
}
} else if (codegen_->GetInstructionSetFeatures().HasDivideInstruction()) {
locations->SetInAt(0, Location::RequiresRegister());
locations->SetInAt(1, Location::RequiresRegister());
locations->SetOut(Location::RequiresRegister(), Location::kNoOutputOverlap);
locations->AddTemp(Location::RequiresRegister());
} else {
InvokeRuntimeCallingConventionARMVIXL calling_convention;
locations->SetInAt(0, LocationFrom(calling_convention.GetRegisterAt(0)));
locations->SetInAt(1, LocationFrom(calling_convention.GetRegisterAt(1)));
// Note: divmod will compute both the quotient and the remainder as the pair R0 and R1, but
// we only need the latter.
locations->SetOut(LocationFrom(r1));
}
break;
}
case Primitive::kPrimLong: {
InvokeRuntimeCallingConventionARMVIXL calling_convention;
locations->SetInAt(0, LocationFrom(
calling_convention.GetRegisterAt(0), calling_convention.GetRegisterAt(1)));
locations->SetInAt(1, LocationFrom(
calling_convention.GetRegisterAt(2), calling_convention.GetRegisterAt(3)));
// The runtime helper puts the output in R2,R3.
locations->SetOut(LocationFrom(r2, r3));
break;
}
case Primitive::kPrimFloat: {
InvokeRuntimeCallingConventionARMVIXL calling_convention;
locations->SetInAt(0, LocationFrom(calling_convention.GetFpuRegisterAt(0)));
locations->SetInAt(1, LocationFrom(calling_convention.GetFpuRegisterAt(1)));
locations->SetOut(LocationFrom(s0));
break;
}
case Primitive::kPrimDouble: {
InvokeRuntimeCallingConventionARMVIXL calling_convention;
locations->SetInAt(0, LocationFrom(
calling_convention.GetFpuRegisterAt(0), calling_convention.GetFpuRegisterAt(1)));
locations->SetInAt(1, LocationFrom(
calling_convention.GetFpuRegisterAt(2), calling_convention.GetFpuRegisterAt(3)));
locations->SetOut(LocationFrom(s0, s1));
break;
}
default:
LOG(FATAL) << "Unexpected rem type " << type;
}
}
void InstructionCodeGeneratorARMVIXL::VisitRem(HRem* rem) {
LocationSummary* locations = rem->GetLocations();
Location second = locations->InAt(1);
Primitive::Type type = rem->GetResultType();
switch (type) {
case Primitive::kPrimInt: {
vixl32::Register reg1 = InputRegisterAt(rem, 0);
vixl32::Register out_reg = OutputRegister(rem);
if (second.IsConstant()) {
GenerateDivRemConstantIntegral(rem);
} else if (codegen_->GetInstructionSetFeatures().HasDivideInstruction()) {
vixl32::Register reg2 = RegisterFrom(second);
vixl32::Register temp = RegisterFrom(locations->GetTemp(0));
// temp = reg1 / reg2 (integer division)
// dest = reg1 - temp * reg2
__ Sdiv(temp, reg1, reg2);
__ Mls(out_reg, temp, reg2, reg1);
} else {
InvokeRuntimeCallingConventionARMVIXL calling_convention;
DCHECK(reg1.Is(calling_convention.GetRegisterAt(0)));
DCHECK(RegisterFrom(second).Is(calling_convention.GetRegisterAt(1)));
DCHECK(out_reg.Is(r1));
codegen_->InvokeRuntime(kQuickIdivmod, rem, rem->GetDexPc());
CheckEntrypointTypes<kQuickIdivmod, int32_t, int32_t, int32_t>();
}
break;
}
case Primitive::kPrimLong: {
codegen_->InvokeRuntime(kQuickLmod, rem, rem->GetDexPc());
CheckEntrypointTypes<kQuickLmod, int64_t, int64_t, int64_t>();
break;
}
case Primitive::kPrimFloat: {
codegen_->InvokeRuntime(kQuickFmodf, rem, rem->GetDexPc());
CheckEntrypointTypes<kQuickFmodf, float, float, float>();
break;
}
case Primitive::kPrimDouble: {
codegen_->InvokeRuntime(kQuickFmod, rem, rem->GetDexPc());
CheckEntrypointTypes<kQuickFmod, double, double, double>();
break;
}
default:
LOG(FATAL) << "Unexpected rem type " << type;
}
}
void LocationsBuilderARMVIXL::VisitDivZeroCheck(HDivZeroCheck* instruction) {
LocationSummary* locations = codegen_->CreateThrowingSlowPathLocations(instruction);
locations->SetInAt(0, Location::RegisterOrConstant(instruction->InputAt(0)));
}
void InstructionCodeGeneratorARMVIXL::VisitDivZeroCheck(HDivZeroCheck* instruction) {
DivZeroCheckSlowPathARMVIXL* slow_path =
new (GetGraph()->GetArena()) DivZeroCheckSlowPathARMVIXL(instruction);
codegen_->AddSlowPath(slow_path);
LocationSummary* locations = instruction->GetLocations();
Location value = locations->InAt(0);
switch (instruction->GetType()) {
case Primitive::kPrimBoolean:
case Primitive::kPrimByte:
case Primitive::kPrimChar:
case Primitive::kPrimShort:
case Primitive::kPrimInt: {
if (value.IsRegister()) {
__ CompareAndBranchIfZero(InputRegisterAt(instruction, 0), slow_path->GetEntryLabel());
} else {
DCHECK(value.IsConstant()) << value;
if (Int32ConstantFrom(value) == 0) {
__ B(slow_path->GetEntryLabel());
}
}
break;
}
case Primitive::kPrimLong: {
if (value.IsRegisterPair()) {
UseScratchRegisterScope temps(GetVIXLAssembler());
vixl32::Register temp = temps.Acquire();
__ Orrs(temp, LowRegisterFrom(value), HighRegisterFrom(value));
__ B(eq, slow_path->GetEntryLabel());
} else {
DCHECK(value.IsConstant()) << value;
if (Int64ConstantFrom(value) == 0) {
__ B(slow_path->GetEntryLabel());
}
}
break;
}
default:
LOG(FATAL) << "Unexpected type for HDivZeroCheck " << instruction->GetType();
}
}
void InstructionCodeGeneratorARMVIXL::HandleIntegerRotate(HRor* ror) {
LocationSummary* locations = ror->GetLocations();
vixl32::Register in = InputRegisterAt(ror, 0);
Location rhs = locations->InAt(1);
vixl32::Register out = OutputRegister(ror);
if (rhs.IsConstant()) {
// Arm32 and Thumb2 assemblers require a rotation on the interval [1,31],
// so map all rotations to a +ve. equivalent in that range.
// (e.g. left *or* right by -2 bits == 30 bits in the same direction.)
uint32_t rot = CodeGenerator::GetInt32ValueOf(rhs.GetConstant()) & 0x1F;
if (rot) {
// Rotate, mapping left rotations to right equivalents if necessary.
// (e.g. left by 2 bits == right by 30.)
__ Ror(out, in, rot);
} else if (!out.Is(in)) {
__ Mov(out, in);
}
} else {
__ Ror(out, in, RegisterFrom(rhs));
}
}
// Gain some speed by mapping all Long rotates onto equivalent pairs of Integer
// rotates by swapping input regs (effectively rotating by the first 32-bits of
// a larger rotation) or flipping direction (thus treating larger right/left
// rotations as sub-word sized rotations in the other direction) as appropriate.
void InstructionCodeGeneratorARMVIXL::HandleLongRotate(HRor* ror) {
LocationSummary* locations = ror->GetLocations();
vixl32::Register in_reg_lo = LowRegisterFrom(locations->InAt(0));
vixl32::Register in_reg_hi = HighRegisterFrom(locations->InAt(0));
Location rhs = locations->InAt(1);
vixl32::Register out_reg_lo = LowRegisterFrom(locations->Out());
vixl32::Register out_reg_hi = HighRegisterFrom(locations->Out());
if (rhs.IsConstant()) {
uint64_t rot = CodeGenerator::GetInt64ValueOf(rhs.GetConstant());
// Map all rotations to +ve. equivalents on the interval [0,63].
rot &= kMaxLongShiftDistance;
// For rotates over a word in size, 'pre-rotate' by 32-bits to keep rotate
// logic below to a simple pair of binary orr.
// (e.g. 34 bits == in_reg swap + 2 bits right.)
if (rot >= kArmBitsPerWord) {
rot -= kArmBitsPerWord;
std::swap(in_reg_hi, in_reg_lo);
}
// Rotate, or mov to out for zero or word size rotations.
if (rot != 0u) {
__ Lsr(out_reg_hi, in_reg_hi, Operand::From(rot));
__ Orr(out_reg_hi, out_reg_hi, Operand(in_reg_lo, ShiftType::LSL, kArmBitsPerWord - rot));
__ Lsr(out_reg_lo, in_reg_lo, Operand::From(rot));
__ Orr(out_reg_lo, out_reg_lo, Operand(in_reg_hi, ShiftType::LSL, kArmBitsPerWord - rot));
} else {
__ Mov(out_reg_lo, in_reg_lo);
__ Mov(out_reg_hi, in_reg_hi);
}
} else {
vixl32::Register shift_right = RegisterFrom(locations->GetTemp(0));
vixl32::Register shift_left = RegisterFrom(locations->GetTemp(1));
vixl32::Label end;
vixl32::Label shift_by_32_plus_shift_right;
vixl32::Label* final_label = codegen_->GetFinalLabel(ror, &end);
__ And(shift_right, RegisterFrom(rhs), 0x1F);
__ Lsrs(shift_left, RegisterFrom(rhs), 6);
__ Rsb(LeaveFlags, shift_left, shift_right, Operand::From(kArmBitsPerWord));
__ B(cc, &shift_by_32_plus_shift_right, /* far_target */ false);
// out_reg_hi = (reg_hi << shift_left) | (reg_lo >> shift_right).
// out_reg_lo = (reg_lo << shift_left) | (reg_hi >> shift_right).
__ Lsl(out_reg_hi, in_reg_hi, shift_left);
__ Lsr(out_reg_lo, in_reg_lo, shift_right);
__ Add(out_reg_hi, out_reg_hi, out_reg_lo);
__ Lsl(out_reg_lo, in_reg_lo, shift_left);
__ Lsr(shift_left, in_reg_hi, shift_right);
__ Add(out_reg_lo, out_reg_lo, shift_left);
__ B(final_label);
__ Bind(&shift_by_32_plus_shift_right); // Shift by 32+shift_right.
// out_reg_hi = (reg_hi >> shift_right) | (reg_lo << shift_left).
// out_reg_lo = (reg_lo >> shift_right) | (reg_hi << shift_left).
__ Lsr(out_reg_hi, in_reg_hi, shift_right);
__ Lsl(out_reg_lo, in_reg_lo, shift_left);
__ Add(out_reg_hi, out_reg_hi, out_reg_lo);
__ Lsr(out_reg_lo, in_reg_lo, shift_right);
__ Lsl(shift_right, in_reg_hi, shift_left);
__ Add(out_reg_lo, out_reg_lo, shift_right);
if (end.IsReferenced()) {
__ Bind(&end);
}
}
}
void LocationsBuilderARMVIXL::VisitRor(HRor* ror) {
LocationSummary* locations =
new (GetGraph()->GetArena()) LocationSummary(ror, LocationSummary::kNoCall);
switch (ror->GetResultType()) {
case Primitive::kPrimInt: {
locations->SetInAt(0, Location::RequiresRegister());
locations->SetInAt(1, Location::RegisterOrConstant(ror->InputAt(1)));
locations->SetOut(Location::RequiresRegister(), Location::kNoOutputOverlap);
break;
}
case Primitive::kPrimLong: {
locations->SetInAt(0, Location::RequiresRegister());
if (ror->InputAt(1)->IsConstant()) {
locations->SetInAt(1, Location::ConstantLocation(ror->InputAt(1)->AsConstant()));
} else {
locations->SetInAt(1, Location::RequiresRegister());
locations->AddTemp(Location::RequiresRegister());
locations->AddTemp(Location::RequiresRegister());
}
locations->SetOut(Location::RequiresRegister(), Location::kOutputOverlap);
break;
}
default:
LOG(FATAL) << "Unexpected operation type " << ror->GetResultType();
}
}
void InstructionCodeGeneratorARMVIXL::VisitRor(HRor* ror) {
Primitive::Type type = ror->GetResultType();
switch (type) {
case Primitive::kPrimInt: {
HandleIntegerRotate(ror);
break;
}
case Primitive::kPrimLong: {
HandleLongRotate(ror);
break;
}
default:
LOG(FATAL) << "Unexpected operation type " << type;
UNREACHABLE();
}
}
void LocationsBuilderARMVIXL::HandleShift(HBinaryOperation* op) {
DCHECK(op->IsShl() || op->IsShr() || op->IsUShr());
LocationSummary* locations =
new (GetGraph()->GetArena()) LocationSummary(op, LocationSummary::kNoCall);
switch (op->GetResultType()) {
case Primitive::kPrimInt: {
locations->SetInAt(0, Location::RequiresRegister());
if (op->InputAt(1)->IsConstant()) {
locations->SetInAt(1, Location::ConstantLocation(op->InputAt(1)->AsConstant()));
locations->SetOut(Location::RequiresRegister(), Location::kNoOutputOverlap);
} else {
locations->SetInAt(1, Location::RequiresRegister());
// Make the output overlap, as it will be used to hold the masked
// second input.
locations->SetOut(Location::RequiresRegister(), Location::kOutputOverlap);
}
break;
}
case Primitive::kPrimLong: {
locations->SetInAt(0, Location::RequiresRegister());
if (op->InputAt(1)->IsConstant()) {
locations->SetInAt(1, Location::ConstantLocation(op->InputAt(1)->AsConstant()));
// For simplicity, use kOutputOverlap even though we only require that low registers
// don't clash with high registers which the register allocator currently guarantees.
locations->SetOut(Location::RequiresRegister(), Location::kOutputOverlap);
} else {
locations->SetInAt(1, Location::RequiresRegister());
locations->AddTemp(Location::RequiresRegister());
locations->SetOut(Location::RequiresRegister(), Location::kOutputOverlap);
}
break;
}
default:
LOG(FATAL) << "Unexpected operation type " << op->GetResultType();
}
}
void InstructionCodeGeneratorARMVIXL::HandleShift(HBinaryOperation* op) {
DCHECK(op->IsShl() || op->IsShr() || op->IsUShr());
LocationSummary* locations = op->GetLocations();
Location out = locations->Out();
Location first = locations->InAt(0);
Location second = locations->InAt(1);
Primitive::Type type = op->GetResultType();
switch (type) {
case Primitive::kPrimInt: {
vixl32::Register out_reg = OutputRegister(op);
vixl32::Register first_reg = InputRegisterAt(op, 0);
if (second.IsRegister()) {
vixl32::Register second_reg = RegisterFrom(second);
// ARM doesn't mask the shift count so we need to do it ourselves.
__ And(out_reg, second_reg, kMaxIntShiftDistance);
if (op->IsShl()) {
__ Lsl(out_reg, first_reg, out_reg);
} else if (op->IsShr()) {
__ Asr(out_reg, first_reg, out_reg);
} else {
__ Lsr(out_reg, first_reg, out_reg);
}
} else {
int32_t cst = Int32ConstantFrom(second);
uint32_t shift_value = cst & kMaxIntShiftDistance;
if (shift_value == 0) { // ARM does not support shifting with 0 immediate.
__ Mov(out_reg, first_reg);
} else if (op->IsShl()) {
__ Lsl(out_reg, first_reg, shift_value);
} else if (op->IsShr()) {
__ Asr(out_reg, first_reg, shift_value);
} else {
__ Lsr(out_reg, first_reg, shift_value);
}
}
break;
}
case Primitive::kPrimLong: {
vixl32::Register o_h = HighRegisterFrom(out);
vixl32::Register o_l = LowRegisterFrom(out);
vixl32::Register high = HighRegisterFrom(first);
vixl32::Register low = LowRegisterFrom(first);
if (second.IsRegister()) {
vixl32::Register temp = RegisterFrom(locations->GetTemp(0));
vixl32::Register second_reg = RegisterFrom(second);
if (op->IsShl()) {
__ And(o_l, second_reg, kMaxLongShiftDistance);
// Shift the high part
__ Lsl(o_h, high, o_l);
// Shift the low part and `or` what overflew on the high part
__ Rsb(temp, o_l, Operand::From(kArmBitsPerWord));
__ Lsr(temp, low, temp);
__ Orr(o_h, o_h, temp);
// If the shift is > 32 bits, override the high part
__ Subs(temp, o_l, Operand::From(kArmBitsPerWord));
{
ExactAssemblyScope guard(GetVIXLAssembler(),
2 * vixl32::kMaxInstructionSizeInBytes,
CodeBufferCheckScope::kMaximumSize);
__ it(pl);
__ lsl(pl, o_h, low, temp);
}
// Shift the low part
__ Lsl(o_l, low, o_l);
} else if (op->IsShr()) {
__ And(o_h, second_reg, kMaxLongShiftDistance);
// Shift the low part
__ Lsr(o_l, low, o_h);
// Shift the high part and `or` what underflew on the low part
__ Rsb(temp, o_h, Operand::From(kArmBitsPerWord));
__ Lsl(temp, high, temp);
__ Orr(o_l, o_l, temp);
// If the shift is > 32 bits, override the low part
__ Subs(temp, o_h, Operand::From(kArmBitsPerWord));
{
ExactAssemblyScope guard(GetVIXLAssembler(),
2 * vixl32::kMaxInstructionSizeInBytes,
CodeBufferCheckScope::kMaximumSize);
__ it(pl);
__ asr(pl, o_l, high, temp);
}
// Shift the high part
__ Asr(o_h, high, o_h);
} else {
__ And(o_h, second_reg, kMaxLongShiftDistance);
// same as Shr except we use `Lsr`s and not `Asr`s
__ Lsr(o_l, low, o_h);
__ Rsb(temp, o_h, Operand::From(kArmBitsPerWord));
__ Lsl(temp, high, temp);
__ Orr(o_l, o_l, temp);
__ Subs(temp, o_h, Operand::From(kArmBitsPerWord));
{
ExactAssemblyScope guard(GetVIXLAssembler(),
2 * vixl32::kMaxInstructionSizeInBytes,
CodeBufferCheckScope::kMaximumSize);
__ it(pl);
__ lsr(pl, o_l, high, temp);
}
__ Lsr(o_h, high, o_h);
}
} else {
// Register allocator doesn't create partial overlap.
DCHECK(!o_l.Is(high));
DCHECK(!o_h.Is(low));
int32_t cst = Int32ConstantFrom(second);
uint32_t shift_value = cst & kMaxLongShiftDistance;
if (shift_value > 32) {
if (op->IsShl()) {
__ Lsl(o_h, low, shift_value - 32);
__ Mov(o_l, 0);
} else if (op->IsShr()) {
__ Asr(o_l, high, shift_value - 32);
__ Asr(o_h, high, 31);
} else {
__ Lsr(o_l, high, shift_value - 32);
__ Mov(o_h, 0);
}
} else if (shift_value == 32) {
if (op->IsShl()) {
__ Mov(o_h, low);
__ Mov(o_l, 0);
} else if (op->IsShr()) {
__ Mov(o_l, high);
__ Asr(o_h, high, 31);
} else {
__ Mov(o_l, high);
__ Mov(o_h, 0);
}
} else if (shift_value == 1) {
if (op->IsShl()) {
__ Lsls(o_l, low, 1);
__ Adc(o_h, high, high);
} else if (op->IsShr()) {
__ Asrs(o_h, high, 1);
__ Rrx(o_l, low);
} else {
__ Lsrs(o_h, high, 1);
__ Rrx(o_l, low);
}
} else {
DCHECK(2 <= shift_value && shift_value < 32) << shift_value;
if (op->IsShl()) {
__ Lsl(o_h, high, shift_value);
__ Orr(o_h, o_h, Operand(low, ShiftType::LSR, 32 - shift_value));
__ Lsl(o_l, low, shift_value);
} else if (op->IsShr()) {
__ Lsr(o_l, low, shift_value);
__ Orr(o_l, o_l, Operand(high, ShiftType::LSL, 32 - shift_value));
__ Asr(o_h, high, shift_value);
} else {
__ Lsr(o_l, low, shift_value);
__ Orr(o_l, o_l, Operand(high, ShiftType::LSL, 32 - shift_value));
__ Lsr(o_h, high, shift_value);
}
}
}
break;
}
default:
LOG(FATAL) << "Unexpected operation type " << type;
UNREACHABLE();
}
}
void LocationsBuilderARMVIXL::VisitShl(HShl* shl) {
HandleShift(shl);
}
void InstructionCodeGeneratorARMVIXL::VisitShl(HShl* shl) {
HandleShift(shl);
}
void LocationsBuilderARMVIXL::VisitShr(HShr* shr) {
HandleShift(shr);
}
void InstructionCodeGeneratorARMVIXL::VisitShr(HShr* shr) {
HandleShift(shr);
}
void LocationsBuilderARMVIXL::VisitUShr(HUShr* ushr) {
HandleShift(ushr);
}
void InstructionCodeGeneratorARMVIXL::VisitUShr(HUShr* ushr) {
HandleShift(ushr);
}
void LocationsBuilderARMVIXL::VisitNewInstance(HNewInstance* instruction) {
LocationSummary* locations =
new (GetGraph()->GetArena()) LocationSummary(instruction, LocationSummary::kCallOnMainOnly);
if (instruction->IsStringAlloc()) {
locations->AddTemp(LocationFrom(kMethodRegister));
} else {
InvokeRuntimeCallingConventionARMVIXL calling_convention;
locations->SetInAt(0, LocationFrom(calling_convention.GetRegisterAt(0)));
}
locations->SetOut(LocationFrom(r0));
}
void InstructionCodeGeneratorARMVIXL::VisitNewInstance(HNewInstance* instruction) {
// Note: if heap poisoning is enabled, the entry point takes cares
// of poisoning the reference.
if (instruction->IsStringAlloc()) {
// String is allocated through StringFactory. Call NewEmptyString entry point.
vixl32::Register temp = RegisterFrom(instruction->GetLocations()->GetTemp(0));
MemberOffset code_offset = ArtMethod::EntryPointFromQuickCompiledCodeOffset(kArmPointerSize);
GetAssembler()->LoadFromOffset(kLoadWord, temp, tr, QUICK_ENTRY_POINT(pNewEmptyString));
GetAssembler()->LoadFromOffset(kLoadWord, lr, temp, code_offset.Int32Value());
// blx in T32 has only 16bit encoding that's why a stricter check for the scope is used.
ExactAssemblyScope aas(GetVIXLAssembler(),
vixl32::k16BitT32InstructionSizeInBytes,
CodeBufferCheckScope::kExactSize);
__ blx(lr);
codegen_->RecordPcInfo(instruction, instruction->GetDexPc());
} else {
codegen_->InvokeRuntime(instruction->GetEntrypoint(), instruction, instruction->GetDexPc());
CheckEntrypointTypes<kQuickAllocObjectWithChecks, void*, mirror::Class*>();
}
}
void LocationsBuilderARMVIXL::VisitNewArray(HNewArray* instruction) {
LocationSummary* locations =
new (GetGraph()->GetArena()) LocationSummary(instruction, LocationSummary::kCallOnMainOnly);
InvokeRuntimeCallingConventionARMVIXL calling_convention;
locations->SetOut(LocationFrom(r0));
locations->SetInAt(0, LocationFrom(calling_convention.GetRegisterAt(0)));
locations->SetInAt(1, LocationFrom(calling_convention.GetRegisterAt(1)));
}
void InstructionCodeGeneratorARMVIXL::VisitNewArray(HNewArray* instruction) {
// Note: if heap poisoning is enabled, the entry point takes cares
// of poisoning the reference.
QuickEntrypointEnum entrypoint =
CodeGenerator::GetArrayAllocationEntrypoint(instruction->GetLoadClass()->GetClass());
codegen_->InvokeRuntime(entrypoint, instruction, instruction->GetDexPc());
CheckEntrypointTypes<kQuickAllocArrayResolved, void*, mirror::Class*, int32_t>();
DCHECK(!codegen_->IsLeafMethod());
}
void LocationsBuilderARMVIXL::VisitParameterValue(HParameterValue* instruction) {
LocationSummary* locations =
new (GetGraph()->GetArena()) LocationSummary(instruction, LocationSummary::kNoCall);
Location location = parameter_visitor_.GetNextLocation(instruction->GetType());
if (location.IsStackSlot()) {
location = Location::StackSlot(location.GetStackIndex() + codegen_->GetFrameSize());
} else if (location.IsDoubleStackSlot()) {
location = Location::DoubleStackSlot(location.GetStackIndex() + codegen_->GetFrameSize());
}
locations->SetOut(location);
}
void InstructionCodeGeneratorARMVIXL::VisitParameterValue(
HParameterValue* instruction ATTRIBUTE_UNUSED) {
// Nothing to do, the parameter is already at its location.
}
void LocationsBuilderARMVIXL::VisitCurrentMethod(HCurrentMethod* instruction) {
LocationSummary* locations =
new (GetGraph()->GetArena()) LocationSummary(instruction, LocationSummary::kNoCall);
locations->SetOut(LocationFrom(kMethodRegister));
}
void InstructionCodeGeneratorARMVIXL::VisitCurrentMethod(
HCurrentMethod* instruction ATTRIBUTE_UNUSED) {
// Nothing to do, the method is already at its location.
}
void LocationsBuilderARMVIXL::VisitNot(HNot* not_) {
LocationSummary* locations =
new (GetGraph()->GetArena()) LocationSummary(not_, LocationSummary::kNoCall);
locations->SetInAt(0, Location::RequiresRegister());
locations->SetOut(Location::RequiresRegister(), Location::kNoOutputOverlap);
}
void InstructionCodeGeneratorARMVIXL::VisitNot(HNot* not_) {
LocationSummary* locations = not_->GetLocations();
Location out = locations->Out();
Location in = locations->InAt(0);
switch (not_->GetResultType()) {
case Primitive::kPrimInt:
__ Mvn(OutputRegister(not_), InputRegisterAt(not_, 0));
break;
case Primitive::kPrimLong:
__ Mvn(LowRegisterFrom(out), LowRegisterFrom(in));
__ Mvn(HighRegisterFrom(out), HighRegisterFrom(in));
break;
default:
LOG(FATAL) << "Unimplemented type for not operation " << not_->GetResultType();
}
}
void LocationsBuilderARMVIXL::VisitBooleanNot(HBooleanNot* bool_not) {
LocationSummary* locations =
new (GetGraph()->GetArena()) LocationSummary(bool_not, LocationSummary::kNoCall);
locations->SetInAt(0, Location::RequiresRegister());
locations->SetOut(Location::RequiresRegister(), Location::kNoOutputOverlap);
}
void InstructionCodeGeneratorARMVIXL::VisitBooleanNot(HBooleanNot* bool_not) {
__ Eor(OutputRegister(bool_not), InputRegister(bool_not), 1);
}
void LocationsBuilderARMVIXL::VisitCompare(HCompare* compare) {
LocationSummary* locations =
new (GetGraph()->GetArena()) LocationSummary(compare, LocationSummary::kNoCall);
switch (compare->InputAt(0)->GetType()) {
case Primitive::kPrimBoolean:
case Primitive::kPrimByte:
case Primitive::kPrimShort:
case Primitive::kPrimChar:
case Primitive::kPrimInt:
case Primitive::kPrimLong: {
locations->SetInAt(0, Location::RequiresRegister());
locations->SetInAt(1, Location::RequiresRegister());
// Output overlaps because it is written before doing the low comparison.
locations->SetOut(Location::RequiresRegister(), Location::kOutputOverlap);
break;
}
case Primitive::kPrimFloat:
case Primitive::kPrimDouble: {
locations->SetInAt(0, Location::RequiresFpuRegister());
locations->SetInAt(1, ArithmeticZeroOrFpuRegister(compare->InputAt(1)));
locations->SetOut(Location::RequiresRegister());
break;
}
default:
LOG(FATAL) << "Unexpected type for compare operation " << compare->InputAt(0)->GetType();
}
}
void InstructionCodeGeneratorARMVIXL::VisitCompare(HCompare* compare) {
LocationSummary* locations = compare->GetLocations();
vixl32::Register out = OutputRegister(compare);
Location left = locations->InAt(0);
Location right = locations->InAt(1);
vixl32::Label less, greater, done;
vixl32::Label* final_label = codegen_->GetFinalLabel(compare, &done);
Primitive::Type type = compare->InputAt(0)->GetType();
vixl32::Condition less_cond = vixl32::Condition(kNone);
switch (type) {
case Primitive::kPrimBoolean:
case Primitive::kPrimByte:
case Primitive::kPrimShort:
case Primitive::kPrimChar:
case Primitive::kPrimInt: {
// Emit move to `out` before the `Cmp`, as `Mov` might affect the status flags.
__ Mov(out, 0);
__ Cmp(RegisterFrom(left), RegisterFrom(right)); // Signed compare.
less_cond = lt;
break;
}
case Primitive::kPrimLong: {
__ Cmp(HighRegisterFrom(left), HighRegisterFrom(right)); // Signed compare.
__ B(lt, &less, /* far_target */ false);
__ B(gt, &greater, /* far_target */ false);
// Emit move to `out` before the last `Cmp`, as `Mov` might affect the status flags.
__ Mov(out, 0);
__ Cmp(LowRegisterFrom(left), LowRegisterFrom(right)); // Unsigned compare.
less_cond = lo;
break;
}
case Primitive::kPrimFloat:
case Primitive::kPrimDouble: {
__ Mov(out, 0);
GenerateVcmp(compare, codegen_);
// To branch on the FP compare result we transfer FPSCR to APSR (encoded as PC in VMRS).
__ Vmrs(RegisterOrAPSR_nzcv(kPcCode), FPSCR);
less_cond = ARMFPCondition(kCondLT, compare->IsGtBias());
break;
}
default:
LOG(FATAL) << "Unexpected compare type " << type;
UNREACHABLE();
}
__ B(eq, final_label, /* far_target */ false);
__ B(less_cond, &less, /* far_target */ false);
__ Bind(&greater);
__ Mov(out, 1);
__ B(final_label);
__ Bind(&less);
__ Mov(out, -1);
if (done.IsReferenced()) {
__ Bind(&done);
}
}
void LocationsBuilderARMVIXL::VisitPhi(HPhi* instruction) {
LocationSummary* locations =
new (GetGraph()->GetArena()) LocationSummary(instruction, LocationSummary::kNoCall);
for (size_t i = 0, e = locations->GetInputCount(); i < e; ++i) {
locations->SetInAt(i, Location::Any());
}
locations->SetOut(Location::Any());
}
void InstructionCodeGeneratorARMVIXL::VisitPhi(HPhi* instruction ATTRIBUTE_UNUSED) {
LOG(FATAL) << "Unreachable";
}
void CodeGeneratorARMVIXL::GenerateMemoryBarrier(MemBarrierKind kind) {
// TODO (ported from quick): revisit ARM barrier kinds.
DmbOptions flavor = DmbOptions::ISH; // Quiet C++ warnings.
switch (kind) {
case MemBarrierKind::kAnyStore:
case MemBarrierKind::kLoadAny:
case MemBarrierKind::kAnyAny: {
flavor = DmbOptions::ISH;
break;
}
case MemBarrierKind::kStoreStore: {
flavor = DmbOptions::ISHST;
break;
}
default:
LOG(FATAL) << "Unexpected memory barrier " << kind;
}
__ Dmb(flavor);
}
void InstructionCodeGeneratorARMVIXL::GenerateWideAtomicLoad(vixl32::Register addr,
uint32_t offset,
vixl32::Register out_lo,
vixl32::Register out_hi) {
UseScratchRegisterScope temps(GetVIXLAssembler());
if (offset != 0) {
vixl32::Register temp = temps.Acquire();
__ Add(temp, addr, offset);
addr = temp;
}
__ Ldrexd(out_lo, out_hi, MemOperand(addr));
}
void InstructionCodeGeneratorARMVIXL::GenerateWideAtomicStore(vixl32::Register addr,
uint32_t offset,
vixl32::Register value_lo,
vixl32::Register value_hi,
vixl32::Register temp1,
vixl32::Register temp2,
HInstruction* instruction) {
UseScratchRegisterScope temps(GetVIXLAssembler());
vixl32::Label fail;
if (offset != 0) {
vixl32::Register temp = temps.Acquire();
__ Add(temp, addr, offset);
addr = temp;
}
__ Bind(&fail);
{
// Ensure the pc position is recorded immediately after the `ldrexd` instruction.
ExactAssemblyScope aas(GetVIXLAssembler(),
vixl32::kMaxInstructionSizeInBytes,
CodeBufferCheckScope::kMaximumSize);
// We need a load followed by store. (The address used in a STREX instruction must
// be the same as the address in the most recently executed LDREX instruction.)
__ ldrexd(temp1, temp2, MemOperand(addr));
codegen_->MaybeRecordImplicitNullCheck(instruction);
}
__ Strexd(temp1, value_lo, value_hi, MemOperand(addr));
__ CompareAndBranchIfNonZero(temp1, &fail);
}
void LocationsBuilderARMVIXL::HandleFieldSet(
HInstruction* instruction, const FieldInfo& field_info) {
DCHECK(instruction->IsInstanceFieldSet() || instruction->IsStaticFieldSet());
LocationSummary* locations =
new (GetGraph()->GetArena()) LocationSummary(instruction, LocationSummary::kNoCall);
locations->SetInAt(0, Location::RequiresRegister());
Primitive::Type field_type = field_info.GetFieldType();
if (Primitive::IsFloatingPointType(field_type)) {
locations->SetInAt(1, Location::RequiresFpuRegister());
} else {
locations->SetInAt(1, Location::RequiresRegister());
}
bool is_wide = field_type == Primitive::kPrimLong || field_type == Primitive::kPrimDouble;
bool generate_volatile = field_info.IsVolatile()
&& is_wide
&& !codegen_->GetInstructionSetFeatures().HasAtomicLdrdAndStrd();
bool needs_write_barrier =
CodeGenerator::StoreNeedsWriteBarrier(field_type, instruction->InputAt(1));
// Temporary registers for the write barrier.
// TODO: consider renaming StoreNeedsWriteBarrier to StoreNeedsGCMark.
if (needs_write_barrier) {
locations->AddTemp(Location::RequiresRegister()); // Possibly used for reference poisoning too.
locations->AddTemp(Location::RequiresRegister());
} else if (generate_volatile) {
// ARM encoding have some additional constraints for ldrexd/strexd:
// - registers need to be consecutive
// - the first register should be even but not R14.
// We don't test for ARM yet, and the assertion makes sure that we
// revisit this if we ever enable ARM encoding.
DCHECK_EQ(InstructionSet::kThumb2, codegen_->GetInstructionSet());
locations->AddTemp(Location::RequiresRegister());
locations->AddTemp(Location::RequiresRegister());
if (field_type == Primitive::kPrimDouble) {
// For doubles we need two more registers to copy the value.
locations->AddTemp(LocationFrom(r2));
locations->AddTemp(LocationFrom(r3));
}
}
}
void InstructionCodeGeneratorARMVIXL::HandleFieldSet(HInstruction* instruction,
const FieldInfo& field_info,
bool value_can_be_null) {
DCHECK(instruction->IsInstanceFieldSet() || instruction->IsStaticFieldSet());
LocationSummary* locations = instruction->GetLocations();
vixl32::Register base = InputRegisterAt(instruction, 0);
Location value = locations->InAt(1);
bool is_volatile = field_info.IsVolatile();
bool atomic_ldrd_strd = codegen_->GetInstructionSetFeatures().HasAtomicLdrdAndStrd();
Primitive::Type field_type = field_info.GetFieldType();
uint32_t offset = field_info.GetFieldOffset().Uint32Value();
bool needs_write_barrier =
CodeGenerator::StoreNeedsWriteBarrier(field_type, instruction->InputAt(1));
if (is_volatile) {
codegen_->GenerateMemoryBarrier(MemBarrierKind::kAnyStore);
}
switch (field_type) {
case Primitive::kPrimBoolean:
case Primitive::kPrimByte: {
GetAssembler()->StoreToOffset(kStoreByte, RegisterFrom(value), base, offset);
break;
}
case Primitive::kPrimShort:
case Primitive::kPrimChar: {
GetAssembler()->StoreToOffset(kStoreHalfword, RegisterFrom(value), base, offset);
break;
}
case Primitive::kPrimInt:
case Primitive::kPrimNot: {
if (kPoisonHeapReferences && needs_write_barrier) {
// Note that in the case where `value` is a null reference,
// we do not enter this block, as a null reference does not
// need poisoning.
DCHECK_EQ(field_type, Primitive::kPrimNot);
vixl32::Register temp = RegisterFrom(locations->GetTemp(0));
__ Mov(temp, RegisterFrom(value));
GetAssembler()->PoisonHeapReference(temp);
GetAssembler()->StoreToOffset(kStoreWord, temp, base, offset);
} else {
GetAssembler()->StoreToOffset(kStoreWord, RegisterFrom(value), base, offset);
}
break;
}
case Primitive::kPrimLong: {
if (is_volatile && !atomic_ldrd_strd) {
GenerateWideAtomicStore(base,
offset,
LowRegisterFrom(value),
HighRegisterFrom(value),
RegisterFrom(locations->GetTemp(0)),
RegisterFrom(locations->GetTemp(1)),
instruction);
} else {
GetAssembler()->StoreToOffset(kStoreWordPair, LowRegisterFrom(value), base, offset);
codegen_->MaybeRecordImplicitNullCheck(instruction);
}
break;
}
case Primitive::kPrimFloat: {
GetAssembler()->StoreSToOffset(SRegisterFrom(value), base, offset);
break;
}
case Primitive::kPrimDouble: {
vixl32::DRegister value_reg = DRegisterFrom(value);
if (is_volatile && !atomic_ldrd_strd) {
vixl32::Register value_reg_lo = RegisterFrom(locations->GetTemp(0));
vixl32::Register value_reg_hi = RegisterFrom(locations->GetTemp(1));
__ Vmov(value_reg_lo, value_reg_hi, value_reg);
GenerateWideAtomicStore(base,
offset,
value_reg_lo,
value_reg_hi,
RegisterFrom(locations->GetTemp(2)),
RegisterFrom(locations->GetTemp(3)),
instruction);
} else {
GetAssembler()->StoreDToOffset(value_reg, base, offset);
codegen_->MaybeRecordImplicitNullCheck(instruction);
}
break;
}
case Primitive::kPrimVoid:
LOG(FATAL) << "Unreachable type " << field_type;
UNREACHABLE();
}
// Longs and doubles are handled in the switch.
if (field_type != Primitive::kPrimLong && field_type != Primitive::kPrimDouble) {
// TODO(VIXL): Here and for other calls to `MaybeRecordImplicitNullCheck` in this method, we
// should use a scope and the assembler to emit the store instruction to guarantee that we
// record the pc at the correct position. But the `Assembler` does not automatically handle
// unencodable offsets. Practically, everything is fine because the helper and VIXL, at the time
// of writing, do generate the store instruction last.
codegen_->MaybeRecordImplicitNullCheck(instruction);
}
if (CodeGenerator::StoreNeedsWriteBarrier(field_type, instruction->InputAt(1))) {
vixl32::Register temp = RegisterFrom(locations->GetTemp(0));
vixl32::Register card = RegisterFrom(locations->GetTemp(1));
codegen_->MarkGCCard(temp, card, base, RegisterFrom(value), value_can_be_null);
}
if (is_volatile) {
codegen_->GenerateMemoryBarrier(MemBarrierKind::kAnyAny);
}
}
void LocationsBuilderARMVIXL::HandleFieldGet(HInstruction* instruction,
const FieldInfo& field_info) {
DCHECK(instruction->IsInstanceFieldGet() || instruction->IsStaticFieldGet());
bool object_field_get_with_read_barrier =
kEmitCompilerReadBarrier && (field_info.GetFieldType() == Primitive::kPrimNot);
LocationSummary* locations =
new (GetGraph()->GetArena()) LocationSummary(instruction,
object_field_get_with_read_barrier ?
LocationSummary::kCallOnSlowPath :
LocationSummary::kNoCall);
if (object_field_get_with_read_barrier && kUseBakerReadBarrier) {
locations->SetCustomSlowPathCallerSaves(RegisterSet::Empty()); // No caller-save registers.
}
locations->SetInAt(0, Location::RequiresRegister());
bool volatile_for_double = field_info.IsVolatile()
&& (field_info.GetFieldType() == Primitive::kPrimDouble)
&& !codegen_->GetInstructionSetFeatures().HasAtomicLdrdAndStrd();
// The output overlaps in case of volatile long: we don't want the
// code generated by GenerateWideAtomicLoad to overwrite the
// object's location. Likewise, in the case of an object field get
// with read barriers enabled, we do not want the load to overwrite
// the object's location, as we need it to emit the read barrier.
bool overlap = (field_info.IsVolatile() && (field_info.GetFieldType() == Primitive::kPrimLong)) ||
object_field_get_with_read_barrier;
if (Primitive::IsFloatingPointType(instruction->GetType())) {
locations->SetOut(Location::RequiresFpuRegister());
} else {
locations->SetOut(Location::RequiresRegister(),
(overlap ? Location::kOutputOverlap : Location::kNoOutputOverlap));
}
if (volatile_for_double) {
// ARM encoding have some additional constraints for ldrexd/strexd:
// - registers need to be consecutive
// - the first register should be even but not R14.
// We don't test for ARM yet, and the assertion makes sure that we
// revisit this if we ever enable ARM encoding.
DCHECK_EQ(InstructionSet::kThumb2, codegen_->GetInstructionSet());
locations->AddTemp(Location::RequiresRegister());
locations->AddTemp(Location::RequiresRegister());
} else if (object_field_get_with_read_barrier && kUseBakerReadBarrier) {
// We need a temporary register for the read barrier marking slow
// path in CodeGeneratorARMVIXL::GenerateFieldLoadWithBakerReadBarrier.
if (kBakerReadBarrierLinkTimeThunksEnableForFields &&
!Runtime::Current()->UseJitCompilation()) {
// If link-time thunks for the Baker read barrier are enabled, for AOT
// loads we need a temporary only if the offset is too big.
if (field_info.GetFieldOffset().Uint32Value() >= kReferenceLoadMinFarOffset) {
locations->AddTemp(Location::RequiresRegister());
}
// And we always need the reserved entrypoint register.
locations->AddTemp(Location::RegisterLocation(kBakerCcEntrypointRegister.GetCode()));
} else {
locations->AddTemp(Location::RequiresRegister());
}
}
}
Location LocationsBuilderARMVIXL::ArithmeticZeroOrFpuRegister(HInstruction* input) {
DCHECK(Primitive::IsFloatingPointType(input->GetType())) << input->GetType();
if ((input->IsFloatConstant() && (input->AsFloatConstant()->IsArithmeticZero())) ||
(input->IsDoubleConstant() && (input->AsDoubleConstant()->IsArithmeticZero()))) {
return Location::ConstantLocation(input->AsConstant());
} else {
return Location::RequiresFpuRegister();
}
}
Location LocationsBuilderARMVIXL::ArmEncodableConstantOrRegister(HInstruction* constant,
Opcode opcode) {
DCHECK(!Primitive::IsFloatingPointType(constant->GetType()));
if (constant->IsConstant() &&
CanEncodeConstantAsImmediate(constant->AsConstant(), opcode)) {
return Location::ConstantLocation(constant->AsConstant());
}
return Location::RequiresRegister();
}
bool LocationsBuilderARMVIXL::CanEncodeConstantAsImmediate(HConstant* input_cst,
Opcode opcode) {
uint64_t value = static_cast<uint64_t>(Int64FromConstant(input_cst));
if (Primitive::Is64BitType(input_cst->GetType())) {
Opcode high_opcode = opcode;
SetCc low_set_cc = kCcDontCare;
switch (opcode) {
case SUB:
// Flip the operation to an ADD.
value = -value;
opcode = ADD;
FALLTHROUGH_INTENDED;
case ADD:
if (Low32Bits(value) == 0u) {
return CanEncodeConstantAsImmediate(High32Bits(value), opcode, kCcDontCare);
}
high_opcode = ADC;
low_set_cc = kCcSet;
break;
default:
break;
}
return CanEncodeConstantAsImmediate(Low32Bits(value), opcode, low_set_cc) &&
CanEncodeConstantAsImmediate(High32Bits(value), high_opcode, kCcDontCare);
} else {
return CanEncodeConstantAsImmediate(Low32Bits(value), opcode);
}
}
// TODO(VIXL): Replace art::arm::SetCc` with `vixl32::FlagsUpdate after flags set optimization
// enabled.
bool LocationsBuilderARMVIXL::CanEncodeConstantAsImmediate(uint32_t value,
Opcode opcode,
SetCc set_cc) {
ArmVIXLAssembler* assembler = codegen_->GetAssembler();
if (assembler->ShifterOperandCanHold(opcode, value, set_cc)) {
return true;
}
Opcode neg_opcode = kNoOperand;
uint32_t neg_value = 0;
switch (opcode) {
case AND: neg_opcode = BIC; neg_value = ~value; break;
case ORR: neg_opcode = ORN; neg_value = ~value; break;
case ADD: neg_opcode = SUB; neg_value = -value; break;
case ADC: neg_opcode = SBC; neg_value = ~value; break;
case SUB: neg_opcode = ADD; neg_value = -value; break;
case SBC: neg_opcode = ADC; neg_value = ~value; break;
case MOV: neg_opcode = MVN; neg_value = ~value; break;
default:
return false;
}
if (assembler->ShifterOperandCanHold(neg_opcode, neg_value, set_cc)) {
return true;
}
return opcode == AND && IsPowerOfTwo(value + 1);
}
void InstructionCodeGeneratorARMVIXL::HandleFieldGet(HInstruction* instruction,
const FieldInfo& field_info) {
DCHECK(instruction->IsInstanceFieldGet() || instruction->IsStaticFieldGet());
LocationSummary* locations = instruction->GetLocations();
vixl32::Register base = InputRegisterAt(instruction, 0);
Location out = locations->Out();
bool is_volatile = field_info.IsVolatile();
bool atomic_ldrd_strd = codegen_->GetInstructionSetFeatures().HasAtomicLdrdAndStrd();
Primitive::Type field_type = field_info.GetFieldType();
uint32_t offset = field_info.GetFieldOffset().Uint32Value();
switch (field_type) {
case Primitive::kPrimBoolean:
GetAssembler()->LoadFromOffset(kLoadUnsignedByte, RegisterFrom(out), base, offset);
break;
case Primitive::kPrimByte:
GetAssembler()->LoadFromOffset(kLoadSignedByte, RegisterFrom(out), base, offset);
break;
case Primitive::kPrimShort:
GetAssembler()->LoadFromOffset(kLoadSignedHalfword, RegisterFrom(out), base, offset);
break;
case Primitive::kPrimChar:
GetAssembler()->LoadFromOffset(kLoadUnsignedHalfword, RegisterFrom(out), base, offset);
break;
case Primitive::kPrimInt:
GetAssembler()->LoadFromOffset(kLoadWord, RegisterFrom(out), base, offset);
break;
case Primitive::kPrimNot: {
// /* HeapReference<Object> */ out = *(base + offset)
if (kEmitCompilerReadBarrier && kUseBakerReadBarrier) {
Location temp_loc = locations->GetTemp(0);
// Note that a potential implicit null check is handled in this
// CodeGeneratorARMVIXL::GenerateFieldLoadWithBakerReadBarrier call.
codegen_->GenerateFieldLoadWithBakerReadBarrier(
instruction, out, base, offset, temp_loc, /* needs_null_check */ true);
if (is_volatile) {
codegen_->GenerateMemoryBarrier(MemBarrierKind::kLoadAny);
}
} else {
GetAssembler()->LoadFromOffset(kLoadWord, RegisterFrom(out), base, offset);
codegen_->MaybeRecordImplicitNullCheck(instruction);
if (is_volatile) {
codegen_->GenerateMemoryBarrier(MemBarrierKind::kLoadAny);
}
// If read barriers are enabled, emit read barriers other than
// Baker's using a slow path (and also unpoison the loaded
// reference, if heap poisoning is enabled).
codegen_->MaybeGenerateReadBarrierSlow(instruction, out, out, locations->InAt(0), offset);
}
break;
}
case Primitive::kPrimLong:
if (is_volatile && !atomic_ldrd_strd) {
GenerateWideAtomicLoad(base, offset, LowRegisterFrom(out), HighRegisterFrom(out));
} else {
GetAssembler()->LoadFromOffset(kLoadWordPair, LowRegisterFrom(out), base, offset);
}
break;
case Primitive::kPrimFloat:
GetAssembler()->LoadSFromOffset(SRegisterFrom(out), base, offset);
break;
case Primitive::kPrimDouble: {
vixl32::DRegister out_dreg = DRegisterFrom(out);
if (is_volatile && !atomic_ldrd_strd) {
vixl32::Register lo = RegisterFrom(locations->GetTemp(0));
vixl32::Register hi = RegisterFrom(locations->GetTemp(1));
GenerateWideAtomicLoad(base, offset, lo, hi);
// TODO(VIXL): Do we need to be immediately after the ldrexd instruction? If so we need a
// scope.
codegen_->MaybeRecordImplicitNullCheck(instruction);
__ Vmov(out_dreg, lo, hi);
} else {
GetAssembler()->LoadDFromOffset(out_dreg, base, offset);
codegen_->MaybeRecordImplicitNullCheck(instruction);
}
break;
}
case Primitive::kPrimVoid:
LOG(FATAL) << "Unreachable type " << field_type;
UNREACHABLE();
}
if (field_type == Primitive::kPrimNot || field_type == Primitive::kPrimDouble) {
// Potential implicit null checks, in the case of reference or
// double fields, are handled in the previous switch statement.
} else {
// Address cases other than reference and double that may require an implicit null check.
// TODO(VIXL): Here and for other calls to `MaybeRecordImplicitNullCheck` in this method, we
// should use a scope and the assembler to emit the load instruction to guarantee that we
// record the pc at the correct position. But the `Assembler` does not automatically handle
// unencodable offsets. Practically, everything is fine because the helper and VIXL, at the time
// of writing, do generate the store instruction last.
codegen_->MaybeRecordImplicitNullCheck(instruction);
}
if (is_volatile) {
if (field_type == Primitive::kPrimNot) {
// Memory barriers, in the case of references, are also handled
// in the previous switch statement.
} else {
codegen_->GenerateMemoryBarrier(MemBarrierKind::kLoadAny);
}
}
}
void LocationsBuilderARMVIXL::VisitInstanceFieldSet(HInstanceFieldSet* instruction) {
HandleFieldSet(instruction, instruction->GetFieldInfo());
}
void InstructionCodeGeneratorARMVIXL::VisitInstanceFieldSet(HInstanceFieldSet* instruction) {
HandleFieldSet(instruction, instruction->GetFieldInfo(), instruction->GetValueCanBeNull());
}
void LocationsBuilderARMVIXL::VisitInstanceFieldGet(HInstanceFieldGet* instruction) {
HandleFieldGet(instruction, instruction->GetFieldInfo());
}
void InstructionCodeGeneratorARMVIXL::VisitInstanceFieldGet(HInstanceFieldGet* instruction) {
HandleFieldGet(instruction, instruction->GetFieldInfo());
}
void LocationsBuilderARMVIXL::VisitStaticFieldGet(HStaticFieldGet* instruction) {
HandleFieldGet(instruction, instruction->GetFieldInfo());
}
void InstructionCodeGeneratorARMVIXL::VisitStaticFieldGet(HStaticFieldGet* instruction) {
HandleFieldGet(instruction, instruction->GetFieldInfo());
}
void LocationsBuilderARMVIXL::VisitStaticFieldSet(HStaticFieldSet* instruction) {
HandleFieldSet(instruction, instruction->GetFieldInfo());
}
void InstructionCodeGeneratorARMVIXL::VisitStaticFieldSet(HStaticFieldSet* instruction) {
HandleFieldSet(instruction, instruction->GetFieldInfo(), instruction->GetValueCanBeNull());
}
void LocationsBuilderARMVIXL::VisitUnresolvedInstanceFieldGet(
HUnresolvedInstanceFieldGet* instruction) {
FieldAccessCallingConventionARMVIXL calling_convention;
codegen_->CreateUnresolvedFieldLocationSummary(
instruction, instruction->GetFieldType(), calling_convention);
}
void InstructionCodeGeneratorARMVIXL::VisitUnresolvedInstanceFieldGet(
HUnresolvedInstanceFieldGet* instruction) {
FieldAccessCallingConventionARMVIXL calling_convention;
codegen_->GenerateUnresolvedFieldAccess(instruction,
instruction->GetFieldType(),
instruction->GetFieldIndex(),
instruction->GetDexPc(),
calling_convention);
}
void LocationsBuilderARMVIXL::VisitUnresolvedInstanceFieldSet(
HUnresolvedInstanceFieldSet* instruction) {
FieldAccessCallingConventionARMVIXL calling_convention;
codegen_->CreateUnresolvedFieldLocationSummary(
instruction, instruction->GetFieldType(), calling_convention);
}
void InstructionCodeGeneratorARMVIXL::VisitUnresolvedInstanceFieldSet(
HUnresolvedInstanceFieldSet* instruction) {
FieldAccessCallingConventionARMVIXL calling_convention;
codegen_->GenerateUnresolvedFieldAccess(instruction,
instruction->GetFieldType(),
instruction->GetFieldIndex(),
instruction->GetDexPc(),
calling_convention);
}
void LocationsBuilderARMVIXL::VisitUnresolvedStaticFieldGet(
HUnresolvedStaticFieldGet* instruction) {
FieldAccessCallingConventionARMVIXL calling_convention;
codegen_->CreateUnresolvedFieldLocationSummary(
instruction, instruction->GetFieldType(), calling_convention);
}
void InstructionCodeGeneratorARMVIXL::VisitUnresolvedStaticFieldGet(
HUnresolvedStaticFieldGet* instruction) {
FieldAccessCallingConventionARMVIXL calling_convention;
codegen_->GenerateUnresolvedFieldAccess(instruction,
instruction->GetFieldType(),
instruction->GetFieldIndex(),
instruction->GetDexPc(),
calling_convention);
}
void LocationsBuilderARMVIXL::VisitUnresolvedStaticFieldSet(
HUnresolvedStaticFieldSet* instruction) {
FieldAccessCallingConventionARMVIXL calling_convention;
codegen_->CreateUnresolvedFieldLocationSummary(
instruction, instruction->GetFieldType(), calling_convention);
}
void InstructionCodeGeneratorARMVIXL::VisitUnresolvedStaticFieldSet(
HUnresolvedStaticFieldSet* instruction) {
FieldAccessCallingConventionARMVIXL calling_convention;
codegen_->GenerateUnresolvedFieldAccess(instruction,
instruction->GetFieldType(),
instruction->GetFieldIndex(),
instruction->GetDexPc(),
calling_convention);
}
void LocationsBuilderARMVIXL::VisitNullCheck(HNullCheck* instruction) {
LocationSummary* locations = codegen_->CreateThrowingSlowPathLocations(instruction);
locations->SetInAt(0, Location::RequiresRegister());
}
void CodeGeneratorARMVIXL::GenerateImplicitNullCheck(HNullCheck* instruction) {
if (CanMoveNullCheckToUser(instruction)) {
return;
}
UseScratchRegisterScope temps(GetVIXLAssembler());
// Ensure the pc position is recorded immediately after the `ldr` instruction.
ExactAssemblyScope aas(GetVIXLAssembler(),
vixl32::kMaxInstructionSizeInBytes,
CodeBufferCheckScope::kMaximumSize);
__ ldr(temps.Acquire(), MemOperand(InputRegisterAt(instruction, 0)));
RecordPcInfo(instruction, instruction->GetDexPc());
}
void CodeGeneratorARMVIXL::GenerateExplicitNullCheck(HNullCheck* instruction) {
NullCheckSlowPathARMVIXL* slow_path =
new (GetGraph()->GetArena()) NullCheckSlowPathARMVIXL(instruction);
AddSlowPath(slow_path);
__ CompareAndBranchIfZero(InputRegisterAt(instruction, 0), slow_path->GetEntryLabel());
}
void InstructionCodeGeneratorARMVIXL::VisitNullCheck(HNullCheck* instruction) {
codegen_->GenerateNullCheck(instruction);
}
static LoadOperandType GetLoadOperandType(Primitive::Type type) {
switch (type) {
case Primitive::kPrimNot:
return kLoadWord;
case Primitive::kPrimBoolean:
return kLoadUnsignedByte;
case Primitive::kPrimByte:
return kLoadSignedByte;
case Primitive::kPrimChar:
return kLoadUnsignedHalfword;
case Primitive::kPrimShort:
return kLoadSignedHalfword;
case Primitive::kPrimInt:
return kLoadWord;
case Primitive::kPrimLong:
return kLoadWordPair;
case Primitive::kPrimFloat:
return kLoadSWord;
case Primitive::kPrimDouble:
return kLoadDWord;
default:
LOG(FATAL) << "Unreachable type " << type;
UNREACHABLE();
}
}
static StoreOperandType GetStoreOperandType(Primitive::Type type) {
switch (type) {
case Primitive::kPrimNot:
return kStoreWord;
case Primitive::kPrimBoolean:
case Primitive::kPrimByte:
return kStoreByte;
case Primitive::kPrimChar:
case Primitive::kPrimShort:
return kStoreHalfword;
case Primitive::kPrimInt:
return kStoreWord;
case Primitive::kPrimLong:
return kStoreWordPair;
case Primitive::kPrimFloat:
return kStoreSWord;
case Primitive::kPrimDouble:
return kStoreDWord;
default:
LOG(FATAL) << "Unreachable type " << type;
UNREACHABLE();
}
}
void CodeGeneratorARMVIXL::LoadFromShiftedRegOffset(Primitive::Type type,
Location out_loc,
vixl32::Register base,
vixl32::Register reg_index,
vixl32::Condition cond) {
uint32_t shift_count = Primitive::ComponentSizeShift(type);
MemOperand mem_address(base, reg_index, vixl32::LSL, shift_count);
switch (type) {
case Primitive::kPrimByte:
__ Ldrsb(cond, RegisterFrom(out_loc), mem_address);
break;
case Primitive::kPrimBoolean:
__ Ldrb(cond, RegisterFrom(out_loc), mem_address);
break;
case Primitive::kPrimShort:
__ Ldrsh(cond, RegisterFrom(out_loc), mem_address);
break;
case Primitive::kPrimChar:
__ Ldrh(cond, RegisterFrom(out_loc), mem_address);
break;
case Primitive::kPrimNot:
case Primitive::kPrimInt:
__ Ldr(cond, RegisterFrom(out_loc), mem_address);
break;
// T32 doesn't support LoadFromShiftedRegOffset mem address mode for these types.
case Primitive::kPrimLong:
case Primitive::kPrimFloat:
case Primitive::kPrimDouble:
default:
LOG(FATAL) << "Unreachable type " << type;
UNREACHABLE();
}
}
void CodeGeneratorARMVIXL::StoreToShiftedRegOffset(Primitive::Type type,
Location loc,
vixl32::Register base,
vixl32::Register reg_index,
vixl32::Condition cond) {
uint32_t shift_count = Primitive::ComponentSizeShift(type);
MemOperand mem_address(base, reg_index, vixl32::LSL, shift_count);
switch (type) {
case Primitive::kPrimByte:
case Primitive::kPrimBoolean:
__ Strb(cond, RegisterFrom(loc), mem_address);
break;
case Primitive::kPrimShort:
case Primitive::kPrimChar:
__ Strh(cond, RegisterFrom(loc), mem_address);
break;
case Primitive::kPrimNot:
case Primitive::kPrimInt:
__ Str(cond, RegisterFrom(loc), mem_address);
break;
// T32 doesn't support StoreToShiftedRegOffset mem address mode for these types.
case Primitive::kPrimLong:
case Primitive::kPrimFloat:
case Primitive::kPrimDouble:
default:
LOG(FATAL) << "Unreachable type " << type;
UNREACHABLE();
}
}
void LocationsBuilderARMVIXL::VisitArrayGet(HArrayGet* instruction) {
bool object_array_get_with_read_barrier =
kEmitCompilerReadBarrier && (instruction->GetType() == Primitive::kPrimNot);
LocationSummary* locations =
new (GetGraph()->GetArena()) LocationSummary(instruction,
object_array_get_with_read_barrier ?
LocationSummary::kCallOnSlowPath :
LocationSummary::kNoCall);
if (object_array_get_with_read_barrier && kUseBakerReadBarrier) {
locations->SetCustomSlowPathCallerSaves(RegisterSet::Empty()); // No caller-save registers.
}
locations->SetInAt(0, Location::RequiresRegister());
locations->SetInAt(1, Location::RegisterOrConstant(instruction->InputAt(1)));
if (Primitive::IsFloatingPointType(instruction->GetType())) {
locations->SetOut(Location::RequiresFpuRegister(), Location::kNoOutputOverlap);
} else {
// The output overlaps in the case of an object array get with
// read barriers enabled: we do not want the move to overwrite the
// array's location, as we need it to emit the read barrier.
locations->SetOut(
Location::RequiresRegister(),
object_array_get_with_read_barrier ? Location::kOutputOverlap : Location::kNoOutputOverlap);
}
if (object_array_get_with_read_barrier && kUseBakerReadBarrier) {
// We need a temporary register for the read barrier marking slow
// path in CodeGeneratorARMVIXL::GenerateArrayLoadWithBakerReadBarrier.
if (kBakerReadBarrierLinkTimeThunksEnableForFields &&
!Runtime::Current()->UseJitCompilation() &&
instruction->GetIndex()->IsConstant()) {
// Array loads with constant index are treated as field loads.
// If link-time thunks for the Baker read barrier are enabled, for AOT
// constant index loads we need a temporary only if the offset is too big.
uint32_t offset = CodeGenerator::GetArrayDataOffset(instruction);
uint32_t index = instruction->GetIndex()->AsIntConstant()->GetValue();
offset += index << Primitive::ComponentSizeShift(Primitive::kPrimNot);
if (offset >= kReferenceLoadMinFarOffset) {
locations->AddTemp(Location::RequiresRegister());
}
// And we always need the reserved entrypoint register.
locations->AddTemp(Location::RegisterLocation(kBakerCcEntrypointRegister.GetCode()));
} else if (kBakerReadBarrierLinkTimeThunksEnableForArrays &&
!Runtime::Current()->UseJitCompilation() &&
!instruction->GetIndex()->IsConstant()) {
// We need a non-scratch temporary for the array data pointer.
locations->AddTemp(Location::RequiresRegister());
// And we always need the reserved entrypoint register.
locations->AddTemp(Location::RegisterLocation(kBakerCcEntrypointRegister.GetCode()));
} else {
locations->AddTemp(Location::RequiresRegister());
}
} else if (mirror::kUseStringCompression && instruction->IsStringCharAt()) {
// Also need a temporary for String compression feature.
locations->AddTemp(Location::RequiresRegister());
}
}
void InstructionCodeGeneratorARMVIXL::VisitArrayGet(HArrayGet* instruction) {
LocationSummary* locations = instruction->GetLocations();
Location obj_loc = locations->InAt(0);
vixl32::Register obj = InputRegisterAt(instruction, 0);
Location index = locations->InAt(1);
Location out_loc = locations->Out();
uint32_t data_offset = CodeGenerator::GetArrayDataOffset(instruction);
Primitive::Type type = instruction->GetType();
const bool maybe_compressed_char_at = mirror::kUseStringCompression &&
instruction->IsStringCharAt();
HInstruction* array_instr = instruction->GetArray();
bool has_intermediate_address = array_instr->IsIntermediateAddress();
switch (type) {
case Primitive::kPrimBoolean:
case Primitive::kPrimByte:
case Primitive::kPrimShort:
case Primitive::kPrimChar:
case Primitive::kPrimInt: {
vixl32::Register length;
if (maybe_compressed_char_at) {
length = RegisterFrom(locations->GetTemp(0));
uint32_t count_offset = mirror::String::CountOffset().Uint32Value();
GetAssembler()->LoadFromOffset(kLoadWord, length, obj, count_offset);
codegen_->MaybeRecordImplicitNullCheck(instruction);
}
if (index.IsConstant()) {
int32_t const_index = Int32ConstantFrom(index);
if (maybe_compressed_char_at) {
vixl32::Label uncompressed_load, done;
vixl32::Label* final_label = codegen_->GetFinalLabel(instruction, &done);
__ Lsrs(length, length, 1u); // LSRS has a 16-bit encoding, TST (immediate) does not.
static_assert(static_cast<uint32_t>(mirror::StringCompressionFlag::kCompressed) == 0u,
"Expecting 0=compressed, 1=uncompressed");
__ B(cs, &uncompressed_load, /* far_target */ false);
GetAssembler()->LoadFromOffset(kLoadUnsignedByte,
RegisterFrom(out_loc),
obj,
data_offset + const_index);
__ B(final_label);
__ Bind(&uncompressed_load);
GetAssembler()->LoadFromOffset(GetLoadOperandType(Primitive::kPrimChar),
RegisterFrom(out_loc),
obj,
data_offset + (const_index << 1));
if (done.IsReferenced()) {
__ Bind(&done);
}
} else {
uint32_t full_offset = data_offset + (const_index << Primitive::ComponentSizeShift(type));
LoadOperandType load_type = GetLoadOperandType(type);
GetAssembler()->LoadFromOffset(load_type, RegisterFrom(out_loc), obj, full_offset);
}
} else {
UseScratchRegisterScope temps(GetVIXLAssembler());
vixl32::Register temp = temps.Acquire();
if (has_intermediate_address) {
// We do not need to compute the intermediate address from the array: the
// input instruction has done it already. See the comment in
// `TryExtractArrayAccessAddress()`.
if (kIsDebugBuild) {
HIntermediateAddress* tmp = array_instr->AsIntermediateAddress();
DCHECK_EQ(Uint64ConstantFrom(tmp->GetOffset()), data_offset);
}
temp = obj;
} else {
__ Add(temp, obj, data_offset);
}
if (maybe_compressed_char_at) {
vixl32::Label uncompressed_load, done;
vixl32::Label* final_label = codegen_->GetFinalLabel(instruction, &done);
__ Lsrs(length, length, 1u); // LSRS has a 16-bit encoding, TST (immediate) does not.
static_assert(static_cast<uint32_t>(mirror::StringCompressionFlag::kCompressed) == 0u,
"Expecting 0=compressed, 1=uncompressed");
__ B(cs, &uncompressed_load, /* far_target */ false);
__ Ldrb(RegisterFrom(out_loc), MemOperand(temp, RegisterFrom(index), vixl32::LSL, 0));
__ B(final_label);
__ Bind(&uncompressed_load);
__ Ldrh(RegisterFrom(out_loc), MemOperand(temp, RegisterFrom(index), vixl32::LSL, 1));
if (done.IsReferenced()) {
__ Bind(&done);
}
} else {
codegen_->LoadFromShiftedRegOffset(type, out_loc, temp, RegisterFrom(index));
}
}
break;
}
case Primitive::kPrimNot: {
// The read barrier instrumentation of object ArrayGet
// instructions does not support the HIntermediateAddress
// instruction.
DCHECK(!(has_intermediate_address && kEmitCompilerReadBarrier));
static_assert(
sizeof(mirror::HeapReference<mirror::Object>) == sizeof(int32_t),
"art::mirror::HeapReference<art::mirror::Object> and int32_t have different sizes.");
// /* HeapReference<Object> */ out =
// *(obj + data_offset + index * sizeof(HeapReference<Object>))
if (kEmitCompilerReadBarrier && kUseBakerReadBarrier) {
Location temp = locations->GetTemp(0);
// Note that a potential implicit null check is handled in this
// CodeGeneratorARMVIXL::GenerateArrayLoadWithBakerReadBarrier call.
DCHECK(!instruction->CanDoImplicitNullCheckOn(instruction->InputAt(0)));
if (index.IsConstant()) {
// Array load with a constant index can be treated as a field load.
data_offset += Int32ConstantFrom(index) << Primitive::ComponentSizeShift(type);
codegen_->GenerateFieldLoadWithBakerReadBarrier(instruction,
out_loc,
obj,
data_offset,
locations->GetTemp(0),
/* needs_null_check */ false);
} else {
codegen_->GenerateArrayLoadWithBakerReadBarrier(
instruction, out_loc, obj, data_offset, index, temp, /* needs_null_check */ false);
}
} else {
vixl32::Register out = OutputRegister(instruction);
if (index.IsConstant()) {
size_t offset =
(Int32ConstantFrom(index) << TIMES_4) + data_offset;
GetAssembler()->LoadFromOffset(kLoadWord, out, obj, offset);
// TODO(VIXL): Here and for other calls to `MaybeRecordImplicitNullCheck` in this method,
// we should use a scope and the assembler to emit the load instruction to guarantee that
// we record the pc at the correct position. But the `Assembler` does not automatically
// handle unencodable offsets. Practically, everything is fine because the helper and
// VIXL, at the time of writing, do generate the store instruction last.
codegen_->MaybeRecordImplicitNullCheck(instruction);
// If read barriers are enabled, emit read barriers other than
// Baker's using a slow path (and also unpoison the loaded
// reference, if heap poisoning is enabled).
codegen_->MaybeGenerateReadBarrierSlow(instruction, out_loc, out_loc, obj_loc, offset);
} else {
UseScratchRegisterScope temps(GetVIXLAssembler());
vixl32::Register temp = temps.Acquire();
if (has_intermediate_address) {
// We do not need to compute the intermediate address from the array: the
// input instruction has done it already. See the comment in
// `TryExtractArrayAccessAddress()`.
if (kIsDebugBuild) {
HIntermediateAddress* tmp = array_instr->AsIntermediateAddress();
DCHECK_EQ(Uint64ConstantFrom(tmp->GetOffset()), data_offset);
}
temp = obj;
} else {
__ Add(temp, obj, data_offset);
}
codegen_->LoadFromShiftedRegOffset(type, out_loc, temp, RegisterFrom(index));
temps.Close();
// TODO(VIXL): Use a scope to ensure that we record the pc position immediately after the
// load instruction. Practically, everything is fine because the helper and VIXL, at the
// time of writing, do generate the store instruction last.
codegen_->MaybeRecordImplicitNullCheck(instruction);
// If read barriers are enabled, emit read barriers other than
// Baker's using a slow path (and also unpoison the loaded
// reference, if heap poisoning is enabled).
codegen_->MaybeGenerateReadBarrierSlow(
instruction, out_loc, out_loc, obj_loc, data_offset, index);
}
}
break;
}
case Primitive::kPrimLong: {
if (index.IsConstant()) {
size_t offset =
(Int32ConstantFrom(index) << TIMES_8) + data_offset;
GetAssembler()->LoadFromOffset(kLoadWordPair, LowRegisterFrom(out_loc), obj, offset);
} else {
UseScratchRegisterScope temps(GetVIXLAssembler());
vixl32::Register temp = temps.Acquire();
__ Add(temp, obj, Operand(RegisterFrom(index), vixl32::LSL, TIMES_8));
GetAssembler()->LoadFromOffset(kLoadWordPair, LowRegisterFrom(out_loc), temp, data_offset);
}
break;
}
case Primitive::kPrimFloat: {
vixl32::SRegister out = SRegisterFrom(out_loc);
if (index.IsConstant()) {
size_t offset = (Int32ConstantFrom(index) << TIMES_4) + data_offset;
GetAssembler()->LoadSFromOffset(out, obj, offset);
} else {
UseScratchRegisterScope temps(GetVIXLAssembler());
vixl32::Register temp = temps.Acquire();
__ Add(temp, obj, Operand(RegisterFrom(index), vixl32::LSL, TIMES_4));
GetAssembler()->LoadSFromOffset(out, temp, data_offset);
}
break;
}
case Primitive::kPrimDouble: {
if (index.IsConstant()) {
size_t offset = (Int32ConstantFrom(index) << TIMES_8) + data_offset;
GetAssembler()->LoadDFromOffset(DRegisterFrom(out_loc), obj, offset);
} else {
UseScratchRegisterScope temps(GetVIXLAssembler());
vixl32::Register temp = temps.Acquire();
__ Add(temp, obj, Operand(RegisterFrom(index), vixl32::LSL, TIMES_8));
GetAssembler()->LoadDFromOffset(DRegisterFrom(out_loc), temp, data_offset);
}
break;
}
case Primitive::kPrimVoid:
LOG(FATAL) << "Unreachable type " << type;
UNREACHABLE();
}
if (type == Primitive::kPrimNot) {
// Potential implicit null checks, in the case of reference
// arrays, are handled in the previous switch statement.
} else if (!maybe_compressed_char_at) {
// TODO(VIXL): Use a scope to ensure we record the pc info immediately after
// the preceding load instruction.
codegen_->MaybeRecordImplicitNullCheck(instruction);
}
}
void LocationsBuilderARMVIXL::VisitArraySet(HArraySet* instruction) {
Primitive::Type value_type = instruction->GetComponentType();
bool needs_write_barrier =
CodeGenerator::StoreNeedsWriteBarrier(value_type, instruction->GetValue());
bool may_need_runtime_call_for_type_check = instruction->NeedsTypeCheck();
LocationSummary* locations = new (GetGraph()->GetArena()) LocationSummary(
instruction,
may_need_runtime_call_for_type_check ?
LocationSummary::kCallOnSlowPath :
LocationSummary::kNoCall);
locations->SetInAt(0, Location::RequiresRegister());
locations->SetInAt(1, Location::RegisterOrConstant(instruction->InputAt(1)));
if (Primitive::IsFloatingPointType(value_type)) {
locations->SetInAt(2, Location::RequiresFpuRegister());
} else {
locations->SetInAt(2, Location::RequiresRegister());
}
if (needs_write_barrier) {
// Temporary registers for the write barrier.
locations->AddTemp(Location::RequiresRegister()); // Possibly used for ref. poisoning too.
locations->AddTemp(Location::RequiresRegister());
}
}
void InstructionCodeGeneratorARMVIXL::VisitArraySet(HArraySet* instruction) {
LocationSummary* locations = instruction->GetLocations();
vixl32::Register array = InputRegisterAt(instruction, 0);
Location index = locations->InAt(1);
Primitive::Type value_type = instruction->GetComponentType();
bool may_need_runtime_call_for_type_check = instruction->NeedsTypeCheck();
bool needs_write_barrier =
CodeGenerator::StoreNeedsWriteBarrier(value_type, instruction->GetValue());
uint32_t data_offset =
mirror::Array::DataOffset(Primitive::ComponentSize(value_type)).Uint32Value();
Location value_loc = locations->InAt(2);
HInstruction* array_instr = instruction->GetArray();
bool has_intermediate_address = array_instr->IsIntermediateAddress();
switch (value_type) {
case Primitive::kPrimBoolean:
case Primitive::kPrimByte:
case Primitive::kPrimShort:
case Primitive::kPrimChar:
case Primitive::kPrimInt: {
if (index.IsConstant()) {
int32_t const_index = Int32ConstantFrom(index);
uint32_t full_offset =
data_offset + (const_index << Primitive::ComponentSizeShift(value_type));
StoreOperandType store_type = GetStoreOperandType(value_type);
GetAssembler()->StoreToOffset(store_type, RegisterFrom(value_loc), array, full_offset);
} else {
UseScratchRegisterScope temps(GetVIXLAssembler());
vixl32::Register temp = temps.Acquire();
if (has_intermediate_address) {
// We do not need to compute the intermediate address from the array: the
// input instruction has done it already. See the comment in
// `TryExtractArrayAccessAddress()`.
if (kIsDebugBuild) {
HIntermediateAddress* tmp = array_instr->AsIntermediateAddress();
DCHECK_EQ(Uint64ConstantFrom(tmp->GetOffset()), data_offset);
}
temp = array;
} else {
__ Add(temp, array, data_offset);
}
codegen_->StoreToShiftedRegOffset(value_type, value_loc, temp, RegisterFrom(index));
}
break;
}
case Primitive::kPrimNot: {
vixl32::Register value = RegisterFrom(value_loc);
// TryExtractArrayAccessAddress optimization is never applied for non-primitive ArraySet.
// See the comment in instruction_simplifier_shared.cc.
DCHECK(!has_intermediate_address);
if (instruction->InputAt(2)->IsNullConstant()) {
// Just setting null.
if (index.IsConstant()) {
size_t offset =
(Int32ConstantFrom(index) << TIMES_4) + data_offset;
GetAssembler()->StoreToOffset(kStoreWord, value, array, offset);
} else {
DCHECK(index.IsRegister()) << index;
UseScratchRegisterScope temps(GetVIXLAssembler());
vixl32::Register temp = temps.Acquire();
__ Add(temp, array, data_offset);
codegen_->StoreToShiftedRegOffset(value_type, value_loc, temp, RegisterFrom(index));
}
// TODO(VIXL): Use a scope to ensure we record the pc info immediately after the preceding
// store instruction.
codegen_->MaybeRecordImplicitNullCheck(instruction);
DCHECK(!needs_write_barrier);
DCHECK(!may_need_runtime_call_for_type_check);
break;
}
DCHECK(needs_write_barrier);
Location temp1_loc = locations->GetTemp(0);
vixl32::Register temp1 = RegisterFrom(temp1_loc);
Location temp2_loc = locations->GetTemp(1);
vixl32::Register temp2 = RegisterFrom(temp2_loc);
uint32_t class_offset = mirror::Object::ClassOffset().Int32Value();
uint32_t super_offset = mirror::Class::SuperClassOffset().Int32Value();
uint32_t component_offset = mirror::Class::ComponentTypeOffset().Int32Value();
vixl32::Label done;
vixl32::Label* final_label = codegen_->GetFinalLabel(instruction, &done);
SlowPathCodeARMVIXL* slow_path = nullptr;
if (may_need_runtime_call_for_type_check) {
slow_path = new (GetGraph()->GetArena()) ArraySetSlowPathARMVIXL(instruction);
codegen_->AddSlowPath(slow_path);
if (instruction->GetValueCanBeNull()) {
vixl32::Label non_zero;
__ CompareAndBranchIfNonZero(value, &non_zero);
if (index.IsConstant()) {
size_t offset =
(Int32ConstantFrom(index) << TIMES_4) + data_offset;
GetAssembler()->StoreToOffset(kStoreWord, value, array, offset);
} else {
DCHECK(index.IsRegister()) << index;
UseScratchRegisterScope temps(GetVIXLAssembler());
vixl32::Register temp = temps.Acquire();
__ Add(temp, array, data_offset);
codegen_->StoreToShiftedRegOffset(value_type, value_loc, temp, RegisterFrom(index));
}
// TODO(VIXL): Use a scope to ensure we record the pc info immediately after the preceding
// store instruction.
codegen_->MaybeRecordImplicitNullCheck(instruction);
__ B(final_label);
__ Bind(&non_zero);
}
// Note that when read barriers are enabled, the type checks
// are performed without read barriers. This is fine, even in
// the case where a class object is in the from-space after
// the flip, as a comparison involving such a type would not
// produce a false positive; it may of course produce a false
// negative, in which case we would take the ArraySet slow
// path.
{
// Ensure we record the pc position immediately after the `ldr` instruction.
ExactAssemblyScope aas(GetVIXLAssembler(),
vixl32::kMaxInstructionSizeInBytes,
CodeBufferCheckScope::kMaximumSize);
// /* HeapReference<Class> */ temp1 = array->klass_
__ ldr(temp1, MemOperand(array, class_offset));
codegen_->MaybeRecordImplicitNullCheck(instruction);
}
GetAssembler()->MaybeUnpoisonHeapReference(temp1);
// /* HeapReference<Class> */ temp1 = temp1->component_type_
GetAssembler()->LoadFromOffset(kLoadWord, temp1, temp1, component_offset);
// /* HeapReference<Class> */ temp2 = value->klass_
GetAssembler()->LoadFromOffset(kLoadWord, temp2, value, class_offset);
// If heap poisoning is enabled, no need to unpoison `temp1`
// nor `temp2`, as we are comparing two poisoned references.
__ Cmp(temp1, temp2);
if (instruction->StaticTypeOfArrayIsObjectArray()) {
vixl32::Label do_put;
__ B(eq, &do_put, /* far_target */ false);
// If heap poisoning is enabled, the `temp1` reference has
// not been unpoisoned yet; unpoison it now.
GetAssembler()->MaybeUnpoisonHeapReference(temp1);
// /* HeapReference<Class> */ temp1 = temp1->super_class_
GetAssembler()->LoadFromOffset(kLoadWord, temp1, temp1, super_offset);
// If heap poisoning is enabled, no need to unpoison
// `temp1`, as we are comparing against null below.
__ CompareAndBranchIfNonZero(temp1, slow_path->GetEntryLabel());
__ Bind(&do_put);
} else {
__ B(ne, slow_path->GetEntryLabel());
}
}
vixl32::Register source = value;
if (kPoisonHeapReferences) {
// Note that in the case where `value` is a null reference,
// we do not enter this block, as a null reference does not
// need poisoning.
DCHECK_EQ(value_type, Primitive::kPrimNot);
__ Mov(temp1, value);
GetAssembler()->PoisonHeapReference(temp1);
source = temp1;
}
if (index.IsConstant()) {
size_t offset =
(Int32ConstantFrom(index) << TIMES_4) + data_offset;
GetAssembler()->StoreToOffset(kStoreWord, source, array, offset);
} else {
DCHECK(index.IsRegister()) << index;
UseScratchRegisterScope temps(GetVIXLAssembler());
vixl32::Register temp = temps.Acquire();
__ Add(temp, array, data_offset);
codegen_->StoreToShiftedRegOffset(value_type,
LocationFrom(source),
temp,
RegisterFrom(index));
}
if (!may_need_runtime_call_for_type_check) {
// TODO(VIXL): Ensure we record the pc position immediately after the preceding store
// instruction.
codegen_->MaybeRecordImplicitNullCheck(instruction);
}
codegen_->MarkGCCard(temp1, temp2, array, value, instruction->GetValueCanBeNull());
if (done.IsReferenced()) {
__ Bind(&done);
}
if (slow_path != nullptr) {
__ Bind(slow_path->GetExitLabel());
}
break;
}
case Primitive::kPrimLong: {
Location value = locations->InAt(2);
if (index.IsConstant()) {
size_t offset =
(Int32ConstantFrom(index) << TIMES_8) + data_offset;
GetAssembler()->StoreToOffset(kStoreWordPair, LowRegisterFrom(value), array, offset);
} else {
UseScratchRegisterScope temps(GetVIXLAssembler());
vixl32::Register temp = temps.Acquire();
__ Add(temp, array, Operand(RegisterFrom(index), vixl32::LSL, TIMES_8));
GetAssembler()->StoreToOffset(kStoreWordPair, LowRegisterFrom(value), temp, data_offset);
}
break;
}
case Primitive::kPrimFloat: {
Location value = locations->InAt(2);
DCHECK(value.IsFpuRegister());
if (index.IsConstant()) {
size_t offset = (Int32ConstantFrom(index) << TIMES_4) + data_offset;
GetAssembler()->StoreSToOffset(SRegisterFrom(value), array, offset);
} else {
UseScratchRegisterScope temps(GetVIXLAssembler());
vixl32::Register temp = temps.Acquire();
__ Add(temp, array, Operand(RegisterFrom(index), vixl32::LSL, TIMES_4));
GetAssembler()->StoreSToOffset(SRegisterFrom(value), temp, data_offset);
}
break;
}
case Primitive::kPrimDouble: {
Location value = locations->InAt(2);
DCHECK(value.IsFpuRegisterPair());
if (index.IsConstant()) {
size_t offset = (Int32ConstantFrom(index) << TIMES_8) + data_offset;
GetAssembler()->StoreDToOffset(DRegisterFrom(value), array, offset);
} else {
UseScratchRegisterScope temps(GetVIXLAssembler());
vixl32::Register temp = temps.Acquire();
__ Add(temp, array, Operand(RegisterFrom(index), vixl32::LSL, TIMES_8));
GetAssembler()->StoreDToOffset(DRegisterFrom(value), temp, data_offset);
}
break;
}
case Primitive::kPrimVoid:
LOG(FATAL) << "Unreachable type " << value_type;
UNREACHABLE();
}
// Objects are handled in the switch.
if (value_type != Primitive::kPrimNot) {
// TODO(VIXL): Ensure we record the pc position immediately after the preceding store
// instruction.
codegen_->MaybeRecordImplicitNullCheck(instruction);
}
}
void LocationsBuilderARMVIXL::VisitArrayLength(HArrayLength* instruction) {
LocationSummary* locations =
new (GetGraph()->GetArena()) LocationSummary(instruction, LocationSummary::kNoCall);
locations->SetInAt(0, Location::RequiresRegister());
locations->SetOut(Location::RequiresRegister(), Location::kNoOutputOverlap);
}
void InstructionCodeGeneratorARMVIXL::VisitArrayLength(HArrayLength* instruction) {
uint32_t offset = CodeGenerator::GetArrayLengthOffset(instruction);
vixl32::Register obj = InputRegisterAt(instruction, 0);
vixl32::Register out = OutputRegister(instruction);
{
ExactAssemblyScope aas(GetVIXLAssembler(),
vixl32::kMaxInstructionSizeInBytes,
CodeBufferCheckScope::kMaximumSize);
__ ldr(out, MemOperand(obj, offset));
codegen_->MaybeRecordImplicitNullCheck(instruction);
}
// Mask out compression flag from String's array length.
if (mirror::kUseStringCompression && instruction->IsStringLength()) {
__ Lsr(out, out, 1u);
}
}
void LocationsBuilderARMVIXL::VisitIntermediateAddress(HIntermediateAddress* instruction) {
LocationSummary* locations =
new (GetGraph()->GetArena()) LocationSummary(instruction, LocationSummary::kNoCall);
locations->SetInAt(0, Location::RequiresRegister());
locations->SetInAt(1, Location::RegisterOrConstant(instruction->GetOffset()));
locations->SetOut(Location::RequiresRegister(), Location::kNoOutputOverlap);
}
void InstructionCodeGeneratorARMVIXL::VisitIntermediateAddress(HIntermediateAddress* instruction) {
vixl32::Register out = OutputRegister(instruction);
vixl32::Register first = InputRegisterAt(instruction, 0);
Location second = instruction->GetLocations()->InAt(1);
if (second.IsRegister()) {
__ Add(out, first, RegisterFrom(second));
} else {
__ Add(out, first, Int32ConstantFrom(second));
}
}
void LocationsBuilderARMVIXL::VisitIntermediateAddressIndex(
HIntermediateAddressIndex* instruction) {
LOG(FATAL) << "Unreachable " << instruction->GetId();
}
void InstructionCodeGeneratorARMVIXL::VisitIntermediateAddressIndex(
HIntermediateAddressIndex* instruction) {
LOG(FATAL) << "Unreachable " << instruction->GetId();
}
void LocationsBuilderARMVIXL::VisitBoundsCheck(HBoundsCheck* instruction) {
RegisterSet caller_saves = RegisterSet::Empty();
InvokeRuntimeCallingConventionARMVIXL calling_convention;
caller_saves.Add(LocationFrom(calling_convention.GetRegisterAt(0)));
caller_saves.Add(LocationFrom(calling_convention.GetRegisterAt(1)));
LocationSummary* locations = codegen_->CreateThrowingSlowPathLocations(instruction, caller_saves);
HInstruction* index = instruction->InputAt(0);
HInstruction* length = instruction->InputAt(1);
// If both index and length are constants we can statically check the bounds. But if at least one
// of them is not encodable ArmEncodableConstantOrRegister will create
// Location::RequiresRegister() which is not desired to happen. Instead we create constant
// locations.
bool both_const = index->IsConstant() && length->IsConstant();
locations->SetInAt(0, both_const
? Location::ConstantLocation(index->AsConstant())
: ArmEncodableConstantOrRegister(index, CMP));
locations->SetInAt(1, both_const
? Location::ConstantLocation(length->AsConstant())
: ArmEncodableConstantOrRegister(length, CMP));
}
void InstructionCodeGeneratorARMVIXL::VisitBoundsCheck(HBoundsCheck* instruction) {
LocationSummary* locations = instruction->GetLocations();
Location index_loc = locations->InAt(0);
Location length_loc = locations->InAt(1);
if (length_loc.IsConstant()) {
int32_t length = Int32ConstantFrom(length_loc);
if (index_loc.IsConstant()) {
// BCE will remove the bounds check if we are guaranteed to pass.
int32_t index = Int32ConstantFrom(index_loc);
if (index < 0 || index >= length) {
SlowPathCodeARMVIXL* slow_path =
new (GetGraph()->GetArena()) BoundsCheckSlowPathARMVIXL(instruction);
codegen_->AddSlowPath(slow_path);
__ B(slow_path->GetEntryLabel());
} else {
// Some optimization after BCE may have generated this, and we should not
// generate a bounds check if it is a valid range.
}
return;
}
SlowPathCodeARMVIXL* slow_path =
new (GetGraph()->GetArena()) BoundsCheckSlowPathARMVIXL(instruction);
__ Cmp(RegisterFrom(index_loc), length);
codegen_->AddSlowPath(slow_path);
__ B(hs, slow_path->GetEntryLabel());
} else {
SlowPathCodeARMVIXL* slow_path =
new (GetGraph()->GetArena()) BoundsCheckSlowPathARMVIXL(instruction);
__ Cmp(RegisterFrom(length_loc), InputOperandAt(instruction, 0));
codegen_->AddSlowPath(slow_path);
__ B(ls, slow_path->GetEntryLabel());
}
}
void CodeGeneratorARMVIXL::MarkGCCard(vixl32::Register temp,
vixl32::Register card,
vixl32::Register object,
vixl32::Register value,
bool can_be_null) {
vixl32::Label is_null;
if (can_be_null) {
__ CompareAndBranchIfZero(value, &is_null);
}
GetAssembler()->LoadFromOffset(
kLoadWord, card, tr, Thread::CardTableOffset<kArmPointerSize>().Int32Value());
__ Lsr(temp, object, Operand::From(gc::accounting::CardTable::kCardShift));
__ Strb(card, MemOperand(card, temp));
if (can_be_null) {
__ Bind(&is_null);
}
}
void LocationsBuilderARMVIXL::VisitParallelMove(HParallelMove* instruction ATTRIBUTE_UNUSED) {
LOG(FATAL) << "Unreachable";
}
void InstructionCodeGeneratorARMVIXL::VisitParallelMove(HParallelMove* instruction) {
codegen_->GetMoveResolver()->EmitNativeCode(instruction);
}
void LocationsBuilderARMVIXL::VisitSuspendCheck(HSuspendCheck* instruction) {
LocationSummary* locations =
new (GetGraph()->GetArena()) LocationSummary(instruction, LocationSummary::kCallOnSlowPath);
locations->SetCustomSlowPathCallerSaves(RegisterSet::Empty()); // No caller-save registers.
}
void InstructionCodeGeneratorARMVIXL::VisitSuspendCheck(HSuspendCheck* instruction) {
HBasicBlock* block = instruction->GetBlock();
if (block->GetLoopInformation() != nullptr) {
DCHECK(block->GetLoopInformation()->GetSuspendCheck() == instruction);
// The back edge will generate the suspend check.
return;
}
if (block->IsEntryBlock() && instruction->GetNext()->IsGoto()) {
// The goto will generate the suspend check.
return;
}
GenerateSuspendCheck(instruction, nullptr);
}
void InstructionCodeGeneratorARMVIXL::GenerateSuspendCheck(HSuspendCheck* instruction,
HBasicBlock* successor) {
SuspendCheckSlowPathARMVIXL* slow_path =
down_cast<SuspendCheckSlowPathARMVIXL*>(instruction->GetSlowPath());
if (slow_path == nullptr) {
slow_path = new (GetGraph()->GetArena()) SuspendCheckSlowPathARMVIXL(instruction, successor);
instruction->SetSlowPath(slow_path);
codegen_->AddSlowPath(slow_path);
if (successor != nullptr) {
DCHECK(successor->IsLoopHeader());
codegen_->ClearSpillSlotsFromLoopPhisInStackMap(instruction);
}
} else {
DCHECK_EQ(slow_path->GetSuccessor(), successor);
}
UseScratchRegisterScope temps(GetVIXLAssembler());
vixl32::Register temp = temps.Acquire();
GetAssembler()->LoadFromOffset(
kLoadUnsignedHalfword, temp, tr, Thread::ThreadFlagsOffset<kArmPointerSize>().Int32Value());
if (successor == nullptr) {
__ CompareAndBranchIfNonZero(temp, slow_path->GetEntryLabel());
__ Bind(slow_path->GetReturnLabel());
} else {
__ CompareAndBranchIfZero(temp, codegen_->GetLabelOf(successor));
__ B(slow_path->GetEntryLabel());
}
}
ArmVIXLAssembler* ParallelMoveResolverARMVIXL::GetAssembler() const {
return codegen_->GetAssembler();
}
void ParallelMoveResolverARMVIXL::EmitMove(size_t index) {
UseScratchRegisterScope temps(GetAssembler()->GetVIXLAssembler());
MoveOperands* move = moves_[index];
Location source = move->GetSource();
Location destination = move->GetDestination();
if (source.IsRegister()) {
if (destination.IsRegister()) {
__ Mov(RegisterFrom(destination), RegisterFrom(source));
} else if (destination.IsFpuRegister()) {
__ Vmov(SRegisterFrom(destination), RegisterFrom(source));
} else {
DCHECK(destination.IsStackSlot());
GetAssembler()->StoreToOffset(kStoreWord,
RegisterFrom(source),
sp,
destination.GetStackIndex());
}
} else if (source.IsStackSlot()) {
if (destination.IsRegister()) {
GetAssembler()->LoadFromOffset(kLoadWord,
RegisterFrom(destination),
sp,
source.GetStackIndex());
} else if (destination.IsFpuRegister()) {
GetAssembler()->LoadSFromOffset(SRegisterFrom(destination), sp, source.GetStackIndex());
} else {
DCHECK(destination.IsStackSlot());
vixl32::Register temp = temps.Acquire();
GetAssembler()->LoadFromOffset(kLoadWord, temp, sp, source.GetStackIndex());
GetAssembler()->StoreToOffset(kStoreWord, temp, sp, destination.GetStackIndex());
}
} else if (source.IsFpuRegister()) {
if (destination.IsRegister()) {
__ Vmov(RegisterFrom(destination), SRegisterFrom(source));
} else if (destination.IsFpuRegister()) {
__ Vmov(SRegisterFrom(destination), SRegisterFrom(source));
} else {
DCHECK(destination.IsStackSlot());
GetAssembler()->StoreSToOffset(SRegisterFrom(source), sp, destination.GetStackIndex());
}
} else if (source.IsDoubleStackSlot()) {
if (destination.IsDoubleStackSlot()) {
vixl32::DRegister temp = temps.AcquireD();
GetAssembler()->LoadDFromOffset(temp, sp, source.GetStackIndex());
GetAssembler()->StoreDToOffset(temp, sp, destination.GetStackIndex());
} else if (destination.IsRegisterPair()) {
DCHECK(ExpectedPairLayout(destination));
GetAssembler()->LoadFromOffset(
kLoadWordPair, LowRegisterFrom(destination), sp, source.GetStackIndex());
} else {
DCHECK(destination.IsFpuRegisterPair()) << destination;
GetAssembler()->LoadDFromOffset(DRegisterFrom(destination), sp, source.GetStackIndex());
}
} else if (source.IsRegisterPair()) {
if (destination.IsRegisterPair()) {
__ Mov(LowRegisterFrom(destination), LowRegisterFrom(source));
__ Mov(HighRegisterFrom(destination), HighRegisterFrom(source));
} else if (destination.IsFpuRegisterPair()) {
__ Vmov(DRegisterFrom(destination), LowRegisterFrom(source), HighRegisterFrom(source));
} else {
DCHECK(destination.IsDoubleStackSlot()) << destination;
DCHECK(ExpectedPairLayout(source));
GetAssembler()->StoreToOffset(kStoreWordPair,
LowRegisterFrom(source),
sp,
destination.GetStackIndex());
}
} else if (source.IsFpuRegisterPair()) {
if (destination.IsRegisterPair()) {
__ Vmov(LowRegisterFrom(destination), HighRegisterFrom(destination), DRegisterFrom(source));
} else if (destination.IsFpuRegisterPair()) {
__ Vmov(DRegisterFrom(destination), DRegisterFrom(source));
} else {
DCHECK(destination.IsDoubleStackSlot()) << destination;
GetAssembler()->StoreDToOffset(DRegisterFrom(source), sp, destination.GetStackIndex());
}
} else {
DCHECK(source.IsConstant()) << source;
HConstant* constant = source.GetConstant();
if (constant->IsIntConstant() || constant->IsNullConstant()) {
int32_t value = CodeGenerator::GetInt32ValueOf(constant);
if (destination.IsRegister()) {
__ Mov(RegisterFrom(destination), value);
} else {
DCHECK(destination.IsStackSlot());
vixl32::Register temp = temps.Acquire();
__ Mov(temp, value);
GetAssembler()->StoreToOffset(kStoreWord, temp, sp, destination.GetStackIndex());
}
} else if (constant->IsLongConstant()) {
int64_t value = Int64ConstantFrom(source);
if (destination.IsRegisterPair()) {
__ Mov(LowRegisterFrom(destination), Low32Bits(value));
__ Mov(HighRegisterFrom(destination), High32Bits(value));
} else {
DCHECK(destination.IsDoubleStackSlot()) << destination;
vixl32::Register temp = temps.Acquire();
__ Mov(temp, Low32Bits(value));
GetAssembler()->StoreToOffset(kStoreWord, temp, sp, destination.GetStackIndex());
__ Mov(temp, High32Bits(value));
GetAssembler()->StoreToOffset(kStoreWord,
temp,
sp,
destination.GetHighStackIndex(kArmWordSize));
}
} else if (constant->IsDoubleConstant()) {
double value = constant->AsDoubleConstant()->GetValue();
if (destination.IsFpuRegisterPair()) {
__ Vmov(DRegisterFrom(destination), value);
} else {
DCHECK(destination.IsDoubleStackSlot()) << destination;
uint64_t int_value = bit_cast<uint64_t, double>(value);
vixl32::Register temp = temps.Acquire();
__ Mov(temp, Low32Bits(int_value));
GetAssembler()->StoreToOffset(kStoreWord, temp, sp, destination.GetStackIndex());
__ Mov(temp, High32Bits(int_value));
GetAssembler()->StoreToOffset(kStoreWord,
temp,
sp,
destination.GetHighStackIndex(kArmWordSize));
}
} else {
DCHECK(constant->IsFloatConstant()) << constant->DebugName();
float value = constant->AsFloatConstant()->GetValue();
if (destination.IsFpuRegister()) {
__ Vmov(SRegisterFrom(destination), value);
} else {
DCHECK(destination.IsStackSlot());
vixl32::Register temp = temps.Acquire();
__ Mov(temp, bit_cast<int32_t, float>(value));
GetAssembler()->StoreToOffset(kStoreWord, temp, sp, destination.GetStackIndex());
}
}
}
}
void ParallelMoveResolverARMVIXL::Exchange(vixl32::Register reg, int mem) {
UseScratchRegisterScope temps(GetAssembler()->GetVIXLAssembler());
vixl32::Register temp = temps.Acquire();
__ Mov(temp, reg);
GetAssembler()->LoadFromOffset(kLoadWord, reg, sp, mem);
GetAssembler()->StoreToOffset(kStoreWord, temp, sp, mem);
}
void ParallelMoveResolverARMVIXL::Exchange(int mem1, int mem2) {
// TODO(VIXL32): Double check the performance of this implementation.
UseScratchRegisterScope temps(GetAssembler()->GetVIXLAssembler());
vixl32::Register temp1 = temps.Acquire();
ScratchRegisterScope ensure_scratch(
this, temp1.GetCode(), r0.GetCode(), codegen_->GetNumberOfCoreRegisters());
vixl32::Register temp2(ensure_scratch.GetRegister());
int stack_offset = ensure_scratch.IsSpilled() ? kArmWordSize : 0;
GetAssembler()->LoadFromOffset(kLoadWord, temp1, sp, mem1 + stack_offset);
GetAssembler()->LoadFromOffset(kLoadWord, temp2, sp, mem2 + stack_offset);
GetAssembler()->StoreToOffset(kStoreWord, temp1, sp, mem2 + stack_offset);
GetAssembler()->StoreToOffset(kStoreWord, temp2, sp, mem1 + stack_offset);
}
void ParallelMoveResolverARMVIXL::EmitSwap(size_t index) {
MoveOperands* move = moves_[index];
Location source = move->GetSource();
Location destination = move->GetDestination();
UseScratchRegisterScope temps(GetAssembler()->GetVIXLAssembler());
if (source.IsRegister() && destination.IsRegister()) {
vixl32::Register temp = temps.Acquire();
DCHECK(!RegisterFrom(source).Is(temp));
DCHECK(!RegisterFrom(destination).Is(temp));
__ Mov(temp, RegisterFrom(destination));
__ Mov(RegisterFrom(destination), RegisterFrom(source));
__ Mov(RegisterFrom(source), temp);
} else if (source.IsRegister() && destination.IsStackSlot()) {
Exchange(RegisterFrom(source), destination.GetStackIndex());
} else if (source.IsStackSlot() && destination.IsRegister()) {
Exchange(RegisterFrom(destination), source.GetStackIndex());
} else if (source.IsStackSlot() && destination.IsStackSlot()) {
Exchange(source.GetStackIndex(), destination.GetStackIndex());
} else if (source.IsFpuRegister() && destination.IsFpuRegister()) {
vixl32::Register temp = temps.Acquire();
__ Vmov(temp, SRegisterFrom(source));
__ Vmov(SRegisterFrom(source), SRegisterFrom(destination));
__ Vmov(SRegisterFrom(destination), temp);
} else if (source.IsRegisterPair() && destination.IsRegisterPair()) {
vixl32::DRegister temp = temps.AcquireD();
__ Vmov(temp, LowRegisterFrom(source), HighRegisterFrom(source));
__ Mov(LowRegisterFrom(source), LowRegisterFrom(destination));
__ Mov(HighRegisterFrom(source), HighRegisterFrom(destination));
__ Vmov(LowRegisterFrom(destination), HighRegisterFrom(destination), temp);
} else if (source.IsRegisterPair() || destination.IsRegisterPair()) {
vixl32::Register low_reg = LowRegisterFrom(source.IsRegisterPair() ? source : destination);
int mem = source.IsRegisterPair() ? destination.GetStackIndex() : source.GetStackIndex();
DCHECK(ExpectedPairLayout(source.IsRegisterPair() ? source : destination));
vixl32::DRegister temp = temps.AcquireD();
__ Vmov(temp, low_reg, vixl32::Register(low_reg.GetCode() + 1));
GetAssembler()->LoadFromOffset(kLoadWordPair, low_reg, sp, mem);
GetAssembler()->StoreDToOffset(temp, sp, mem);
} else if (source.IsFpuRegisterPair() && destination.IsFpuRegisterPair()) {
vixl32::DRegister first = DRegisterFrom(source);
vixl32::DRegister second = DRegisterFrom(destination);
vixl32::DRegister temp = temps.AcquireD();
__ Vmov(temp, first);
__ Vmov(first, second);
__ Vmov(second, temp);
} else if (source.IsFpuRegisterPair() || destination.IsFpuRegisterPair()) {
vixl32::DRegister reg = source.IsFpuRegisterPair()
? DRegisterFrom(source)
: DRegisterFrom(destination);
int mem = source.IsFpuRegisterPair()
? destination.GetStackIndex()
: source.GetStackIndex();
vixl32::DRegister temp = temps.AcquireD();
__ Vmov(temp, reg);
GetAssembler()->LoadDFromOffset(reg, sp, mem);
GetAssembler()->StoreDToOffset(temp, sp, mem);
} else if (source.IsFpuRegister() || destination.IsFpuRegister()) {
vixl32::SRegister reg = source.IsFpuRegister()
? SRegisterFrom(source)
: SRegisterFrom(destination);
int mem = source.IsFpuRegister()
? destination.GetStackIndex()
: source.GetStackIndex();
vixl32::Register temp = temps.Acquire();
__ Vmov(temp, reg);
GetAssembler()->LoadSFromOffset(reg, sp, mem);
GetAssembler()->StoreToOffset(kStoreWord, temp, sp, mem);
} else if (source.IsDoubleStackSlot() && destination.IsDoubleStackSlot()) {
vixl32::DRegister temp1 = temps.AcquireD();
vixl32::DRegister temp2 = temps.AcquireD();
__ Vldr(temp1, MemOperand(sp, source.GetStackIndex()));
__ Vldr(temp2, MemOperand(sp, destination.GetStackIndex()));
__ Vstr(temp1, MemOperand(sp, destination.GetStackIndex()));
__ Vstr(temp2, MemOperand(sp, source.GetStackIndex()));
} else {
LOG(FATAL) << "Unimplemented" << source << " <-> " << destination;
}
}
void ParallelMoveResolverARMVIXL::SpillScratch(int reg) {
__ Push(vixl32::Register(reg));
}
void ParallelMoveResolverARMVIXL::RestoreScratch(int reg) {
__ Pop(vixl32::Register(reg));
}
HLoadClass::LoadKind CodeGeneratorARMVIXL::GetSupportedLoadClassKind(
HLoadClass::LoadKind desired_class_load_kind) {
switch (desired_class_load_kind) {
case HLoadClass::LoadKind::kInvalid:
LOG(FATAL) << "UNREACHABLE";
UNREACHABLE();
case HLoadClass::LoadKind::kReferrersClass:
break;
case HLoadClass::LoadKind::kBootImageLinkTimePcRelative:
case HLoadClass::LoadKind::kBssEntry:
DCHECK(!Runtime::Current()->UseJitCompilation());
break;
case HLoadClass::LoadKind::kJitTableAddress:
DCHECK(Runtime::Current()->UseJitCompilation());
break;
case HLoadClass::LoadKind::kBootImageAddress:
case HLoadClass::LoadKind::kRuntimeCall:
break;
}
return desired_class_load_kind;
}
void LocationsBuilderARMVIXL::VisitLoadClass(HLoadClass* cls) {
HLoadClass::LoadKind load_kind = cls->GetLoadKind();
if (load_kind == HLoadClass::LoadKind::kRuntimeCall) {
InvokeRuntimeCallingConventionARMVIXL calling_convention;
CodeGenerator::CreateLoadClassRuntimeCallLocationSummary(
cls,
LocationFrom(calling_convention.GetRegisterAt(0)),
LocationFrom(r0));
DCHECK(calling_convention.GetRegisterAt(0).Is(r0));
return;
}
DCHECK(!cls->NeedsAccessCheck());
const bool requires_read_barrier = kEmitCompilerReadBarrier && !cls->IsInBootImage();
LocationSummary::CallKind call_kind = (cls->NeedsEnvironment() || requires_read_barrier)
? LocationSummary::kCallOnSlowPath
: LocationSummary::kNoCall;
LocationSummary* locations = new (GetGraph()->GetArena()) LocationSummary(cls, call_kind);
if (kUseBakerReadBarrier && requires_read_barrier && !cls->NeedsEnvironment()) {
locations->SetCustomSlowPathCallerSaves(RegisterSet::Empty()); // No caller-save registers.
}
if (load_kind == HLoadClass::LoadKind::kReferrersClass) {
locations->SetInAt(0, Location::RequiresRegister());
}
locations->SetOut(Location::RequiresRegister());
if (load_kind == HLoadClass::LoadKind::kBssEntry) {
if (!kUseReadBarrier || kUseBakerReadBarrier) {
// Rely on the type resolution or initialization and marking to save everything we need.
// Note that IP may be clobbered by saving/restoring the live register (only one thanks
// to the custom calling convention) or by marking, so we request a different temp.
locations->AddTemp(Location::RequiresRegister());
RegisterSet caller_saves = RegisterSet::Empty();
InvokeRuntimeCallingConventionARMVIXL calling_convention;
caller_saves.Add(LocationFrom(calling_convention.GetRegisterAt(0)));
// TODO: Add GetReturnLocation() to the calling convention so that we can DCHECK()
// that the the kPrimNot result register is the same as the first argument register.
locations->SetCustomSlowPathCallerSaves(caller_saves);
} else {
// For non-Baker read barrier we have a temp-clobbering call.
}
}
if (kUseBakerReadBarrier && kBakerReadBarrierLinkTimeThunksEnableForGcRoots) {
if (load_kind == HLoadClass::LoadKind::kBssEntry ||
(load_kind == HLoadClass::LoadKind::kReferrersClass &&
!Runtime::Current()->UseJitCompilation())) {
locations->AddTemp(Location::RegisterLocation(kBakerCcEntrypointRegister.GetCode()));
}
}
}
// NO_THREAD_SAFETY_ANALYSIS as we manipulate handles whose internal object we know does not
// move.
void InstructionCodeGeneratorARMVIXL::VisitLoadClass(HLoadClass* cls) NO_THREAD_SAFETY_ANALYSIS {
HLoadClass::LoadKind load_kind = cls->GetLoadKind();
if (load_kind == HLoadClass::LoadKind::kRuntimeCall) {
codegen_->GenerateLoadClassRuntimeCall(cls);
return;
}
DCHECK(!cls->NeedsAccessCheck());
LocationSummary* locations = cls->GetLocations();
Location out_loc = locations->Out();
vixl32::Register out = OutputRegister(cls);
const ReadBarrierOption read_barrier_option = cls->IsInBootImage()
? kWithoutReadBarrier
: kCompilerReadBarrierOption;
bool generate_null_check = false;
switch (load_kind) {
case HLoadClass::LoadKind::kReferrersClass: {
DCHECK(!cls->CanCallRuntime());
DCHECK(!cls->MustGenerateClinitCheck());
// /* GcRoot<mirror::Class> */ out = current_method->declaring_class_
vixl32::Register current_method = InputRegisterAt(cls, 0);
GenerateGcRootFieldLoad(cls,
out_loc,
current_method,
ArtMethod::DeclaringClassOffset().Int32Value(),
read_barrier_option);
break;
}
case HLoadClass::LoadKind::kBootImageLinkTimePcRelative: {
DCHECK(codegen_->GetCompilerOptions().IsBootImage());
DCHECK_EQ(read_barrier_option, kWithoutReadBarrier);
CodeGeneratorARMVIXL::PcRelativePatchInfo* labels =
codegen_->NewPcRelativeTypePatch(cls->GetDexFile(), cls->GetTypeIndex());
codegen_->EmitMovwMovtPlaceholder(labels, out);
break;
}
case HLoadClass::LoadKind::kBootImageAddress: {
DCHECK_EQ(read_barrier_option, kWithoutReadBarrier);
uint32_t address = dchecked_integral_cast<uint32_t>(
reinterpret_cast<uintptr_t>(cls->GetClass().Get()));
DCHECK_NE(address, 0u);
__ Ldr(out, codegen_->DeduplicateBootImageAddressLiteral(address));
break;
}
case HLoadClass::LoadKind::kBssEntry: {
vixl32::Register temp = (!kUseReadBarrier || kUseBakerReadBarrier)
? RegisterFrom(locations->GetTemp(0))
: out;
CodeGeneratorARMVIXL::PcRelativePatchInfo* labels =
codegen_->NewTypeBssEntryPatch(cls->GetDexFile(), cls->GetTypeIndex());
codegen_->EmitMovwMovtPlaceholder(labels, temp);
GenerateGcRootFieldLoad(cls, out_loc, temp, /* offset */ 0, read_barrier_option);
generate_null_check = true;
break;
}
case HLoadClass::LoadKind::kJitTableAddress: {
__ Ldr(out, codegen_->DeduplicateJitClassLiteral(cls->GetDexFile(),
cls->GetTypeIndex(),
cls->GetClass()));
// /* GcRoot<mirror::Class> */ out = *out
GenerateGcRootFieldLoad(cls, out_loc, out, /* offset */ 0, read_barrier_option);
break;
}
case HLoadClass::LoadKind::kRuntimeCall:
case HLoadClass::LoadKind::kInvalid:
LOG(FATAL) << "UNREACHABLE";
UNREACHABLE();
}
if (generate_null_check || cls->MustGenerateClinitCheck()) {
DCHECK(cls->CanCallRuntime());
LoadClassSlowPathARMVIXL* slow_path = new (GetGraph()->GetArena()) LoadClassSlowPathARMVIXL(
cls, cls, cls->GetDexPc(), cls->MustGenerateClinitCheck());
codegen_->AddSlowPath(slow_path);
if (generate_null_check) {
__ CompareAndBranchIfZero(out, slow_path->GetEntryLabel());
}
if (cls->MustGenerateClinitCheck()) {
GenerateClassInitializationCheck(slow_path, out);
} else {
__ Bind(slow_path->GetExitLabel());
}
}
}
void LocationsBuilderARMVIXL::VisitClinitCheck(HClinitCheck* check) {
LocationSummary* locations =
new (GetGraph()->GetArena()) LocationSummary(check, LocationSummary::kCallOnSlowPath);
locations->SetInAt(0, Location::RequiresRegister());
if (check->HasUses()) {
locations->SetOut(Location::SameAsFirstInput());
}
}
void InstructionCodeGeneratorARMVIXL::VisitClinitCheck(HClinitCheck* check) {
// We assume the class is not null.
LoadClassSlowPathARMVIXL* slow_path =
new (GetGraph()->GetArena()) LoadClassSlowPathARMVIXL(check->GetLoadClass(),
check,
check->GetDexPc(),
/* do_clinit */ true);
codegen_->AddSlowPath(slow_path);
GenerateClassInitializationCheck(slow_path, InputRegisterAt(check, 0));
}
void InstructionCodeGeneratorARMVIXL::GenerateClassInitializationCheck(
LoadClassSlowPathARMVIXL* slow_path, vixl32::Register class_reg) {
UseScratchRegisterScope temps(GetVIXLAssembler());
vixl32::Register temp = temps.Acquire();
GetAssembler()->LoadFromOffset(kLoadWord,
temp,
class_reg,
mirror::Class::StatusOffset().Int32Value());
__ Cmp(temp, mirror::Class::kStatusInitialized);
__ B(lt, slow_path->GetEntryLabel());
// Even if the initialized flag is set, we may be in a situation where caches are not synced
// properly. Therefore, we do a memory fence.
__ Dmb(ISH);
__ Bind(slow_path->GetExitLabel());
}
HLoadString::LoadKind CodeGeneratorARMVIXL::GetSupportedLoadStringKind(
HLoadString::LoadKind desired_string_load_kind) {
switch (desired_string_load_kind) {
case HLoadString::LoadKind::kBootImageLinkTimePcRelative:
case HLoadString::LoadKind::kBssEntry:
DCHECK(!Runtime::Current()->UseJitCompilation());
break;
case HLoadString::LoadKind::kJitTableAddress:
DCHECK(Runtime::Current()->UseJitCompilation());
break;
case HLoadString::LoadKind::kBootImageAddress:
case HLoadString::LoadKind::kRuntimeCall:
break;
}
return desired_string_load_kind;
}
void LocationsBuilderARMVIXL::VisitLoadString(HLoadString* load) {
LocationSummary::CallKind call_kind = CodeGenerator::GetLoadStringCallKind(load);
LocationSummary* locations = new (GetGraph()->GetArena()) LocationSummary(load, call_kind);
HLoadString::LoadKind load_kind = load->GetLoadKind();
if (load_kind == HLoadString::LoadKind::kRuntimeCall) {
locations->SetOut(LocationFrom(r0));
} else {
locations->SetOut(Location::RequiresRegister());
if (load_kind == HLoadString::LoadKind::kBssEntry) {
if (!kUseReadBarrier || kUseBakerReadBarrier) {
// Rely on the pResolveString and marking to save everything we need, including temps.
// Note that IP may be clobbered by saving/restoring the live register (only one thanks
// to the custom calling convention) or by marking, so we request a different temp.
locations->AddTemp(Location::RequiresRegister());
RegisterSet caller_saves = RegisterSet::Empty();
InvokeRuntimeCallingConventionARMVIXL calling_convention;
caller_saves.Add(LocationFrom(calling_convention.GetRegisterAt(0)));
// TODO: Add GetReturnLocation() to the calling convention so that we can DCHECK()
// that the the kPrimNot result register is the same as the first argument register.
locations->SetCustomSlowPathCallerSaves(caller_saves);
if (kUseBakerReadBarrier && kBakerReadBarrierLinkTimeThunksEnableForGcRoots) {
locations->AddTemp(Location::RegisterLocation(kBakerCcEntrypointRegister.GetCode()));
}
} else {
// For non-Baker read barrier we have a temp-clobbering call.
}
}
}
}
// NO_THREAD_SAFETY_ANALYSIS as we manipulate handles whose internal object we know does not
// move.
void InstructionCodeGeneratorARMVIXL::VisitLoadString(HLoadString* load) NO_THREAD_SAFETY_ANALYSIS {
LocationSummary* locations = load->GetLocations();
Location out_loc = locations->Out();
vixl32::Register out = OutputRegister(load);
HLoadString::LoadKind load_kind = load->GetLoadKind();
switch (load_kind) {
case HLoadString::LoadKind::kBootImageLinkTimePcRelative: {
DCHECK(codegen_->GetCompilerOptions().IsBootImage());
CodeGeneratorARMVIXL::PcRelativePatchInfo* labels =
codegen_->NewPcRelativeStringPatch(load->GetDexFile(), load->GetStringIndex());
codegen_->EmitMovwMovtPlaceholder(labels, out);
return; // No dex cache slow path.
}
case HLoadString::LoadKind::kBootImageAddress: {
uint32_t address = dchecked_integral_cast<uint32_t>(
reinterpret_cast<uintptr_t>(load->GetString().Get()));
DCHECK_NE(address, 0u);
__ Ldr(out, codegen_->DeduplicateBootImageAddressLiteral(address));
return; // No dex cache slow path.
}
case HLoadString::LoadKind::kBssEntry: {
DCHECK(!codegen_->GetCompilerOptions().IsBootImage());
vixl32::Register temp = (!kUseReadBarrier || kUseBakerReadBarrier)
? RegisterFrom(locations->GetTemp(0))
: out;
CodeGeneratorARMVIXL::PcRelativePatchInfo* labels =
codegen_->NewPcRelativeStringPatch(load->GetDexFile(), load->GetStringIndex());
codegen_->EmitMovwMovtPlaceholder(labels, temp);
GenerateGcRootFieldLoad(load, out_loc, temp, /* offset */ 0, kCompilerReadBarrierOption);
LoadStringSlowPathARMVIXL* slow_path =
new (GetGraph()->GetArena()) LoadStringSlowPathARMVIXL(load);
codegen_->AddSlowPath(slow_path);
__ CompareAndBranchIfZero(out, slow_path->GetEntryLabel());
__ Bind(slow_path->GetExitLabel());
return;
}
case HLoadString::LoadKind::kJitTableAddress: {
__ Ldr(out, codegen_->DeduplicateJitStringLiteral(load->GetDexFile(),
load->GetStringIndex(),
load->GetString()));
// /* GcRoot<mirror::String> */ out = *out
GenerateGcRootFieldLoad(load, out_loc, out, /* offset */ 0, kCompilerReadBarrierOption);
return;
}
default:
break;
}
// TODO: Re-add the compiler code to do string dex cache lookup again.
DCHECK_EQ(load->GetLoadKind(), HLoadString::LoadKind::kRuntimeCall);
InvokeRuntimeCallingConventionARMVIXL calling_convention;
__ Mov(calling_convention.GetRegisterAt(0), load->GetStringIndex().index_);
codegen_->InvokeRuntime(kQuickResolveString, load, load->GetDexPc());
CheckEntrypointTypes<kQuickResolveString, void*, uint32_t>();
}
static int32_t GetExceptionTlsOffset() {
return Thread::ExceptionOffset<kArmPointerSize>().Int32Value();
}
void LocationsBuilderARMVIXL::VisitLoadException(HLoadException* load) {
LocationSummary* locations =
new (GetGraph()->GetArena()) LocationSummary(load, LocationSummary::kNoCall);
locations->SetOut(Location::RequiresRegister());
}
void InstructionCodeGeneratorARMVIXL::VisitLoadException(HLoadException* load) {
vixl32::Register out = OutputRegister(load);
GetAssembler()->LoadFromOffset(kLoadWord, out, tr, GetExceptionTlsOffset());
}
void LocationsBuilderARMVIXL::VisitClearException(HClearException* clear) {
new (GetGraph()->GetArena()) LocationSummary(clear, LocationSummary::kNoCall);
}
void InstructionCodeGeneratorARMVIXL::VisitClearException(HClearException* clear ATTRIBUTE_UNUSED) {
UseScratchRegisterScope temps(GetVIXLAssembler());
vixl32::Register temp = temps.Acquire();
__ Mov(temp, 0);
GetAssembler()->StoreToOffset(kStoreWord, temp, tr, GetExceptionTlsOffset());
}
void LocationsBuilderARMVIXL::VisitThrow(HThrow* instruction) {
LocationSummary* locations =
new (GetGraph()->GetArena()) LocationSummary(instruction, LocationSummary::kCallOnMainOnly);
InvokeRuntimeCallingConventionARMVIXL calling_convention;
locations->SetInAt(0, LocationFrom(calling_convention.GetRegisterAt(0)));
}
void InstructionCodeGeneratorARMVIXL::VisitThrow(HThrow* instruction) {
codegen_->InvokeRuntime(kQuickDeliverException, instruction, instruction->GetDexPc());
CheckEntrypointTypes<kQuickDeliverException, void, mirror::Object*>();
}
// Temp is used for read barrier.
static size_t NumberOfInstanceOfTemps(TypeCheckKind type_check_kind) {
if (kEmitCompilerReadBarrier &&
(kUseBakerReadBarrier ||
type_check_kind == TypeCheckKind::kAbstractClassCheck ||
type_check_kind == TypeCheckKind::kClassHierarchyCheck ||
type_check_kind == TypeCheckKind::kArrayObjectCheck)) {
return 1;
}
return 0;
}
// Interface case has 3 temps, one for holding the number of interfaces, one for the current
// interface pointer, one for loading the current interface.
// The other checks have one temp for loading the object's class.
static size_t NumberOfCheckCastTemps(TypeCheckKind type_check_kind) {
if (type_check_kind == TypeCheckKind::kInterfaceCheck) {
return 3;
}
return 1 + NumberOfInstanceOfTemps(type_check_kind);
}
void LocationsBuilderARMVIXL::VisitInstanceOf(HInstanceOf* instruction) {
LocationSummary::CallKind call_kind = LocationSummary::kNoCall;
TypeCheckKind type_check_kind = instruction->GetTypeCheckKind();
bool baker_read_barrier_slow_path = false;
switch (type_check_kind) {
case TypeCheckKind::kExactCheck:
case TypeCheckKind::kAbstractClassCheck:
case TypeCheckKind::kClassHierarchyCheck:
case TypeCheckKind::kArrayObjectCheck:
call_kind =
kEmitCompilerReadBarrier ? LocationSummary::kCallOnSlowPath : LocationSummary::kNoCall;
baker_read_barrier_slow_path = kUseBakerReadBarrier;
break;
case TypeCheckKind::kArrayCheck:
case TypeCheckKind::kUnresolvedCheck:
case TypeCheckKind::kInterfaceCheck:
call_kind = LocationSummary::kCallOnSlowPath;
break;
}
LocationSummary* locations = new (GetGraph()->GetArena()) LocationSummary(instruction, call_kind);
if (baker_read_barrier_slow_path) {
locations->SetCustomSlowPathCallerSaves(RegisterSet::Empty()); // No caller-save registers.
}
locations->SetInAt(0, Location::RequiresRegister());
locations->SetInAt(1, Location::RequiresRegister());
// The "out" register is used as a temporary, so it overlaps with the inputs.
// Note that TypeCheckSlowPathARM uses this register too.
locations->SetOut(Location::RequiresRegister(), Location::kOutputOverlap);
locations->AddRegisterTemps(NumberOfInstanceOfTemps(type_check_kind));
if (kEmitCompilerReadBarrier && kUseBakerReadBarrier) {
codegen_->MaybeAddBakerCcEntrypointTempForFields(locations);
}
}
void InstructionCodeGeneratorARMVIXL::VisitInstanceOf(HInstanceOf* instruction) {
TypeCheckKind type_check_kind = instruction->GetTypeCheckKind();
LocationSummary* locations = instruction->GetLocations();
Location obj_loc = locations->InAt(0);
vixl32::Register obj = InputRegisterAt(instruction, 0);
vixl32::Register cls = InputRegisterAt(instruction, 1);
Location out_loc = locations->Out();
vixl32::Register out = OutputRegister(instruction);
const size_t num_temps = NumberOfInstanceOfTemps(type_check_kind);
DCHECK_LE(num_temps, 1u);
Location maybe_temp_loc = (num_temps >= 1) ? locations->GetTemp(0) : Location::NoLocation();
uint32_t class_offset = mirror::Object::ClassOffset().Int32Value();
uint32_t super_offset = mirror::Class::SuperClassOffset().Int32Value();
uint32_t component_offset = mirror::Class::ComponentTypeOffset().Int32Value();
uint32_t primitive_offset = mirror::Class::PrimitiveTypeOffset().Int32Value();
vixl32::Label done;
vixl32::Label* const final_label = codegen_->GetFinalLabel(instruction, &done);
SlowPathCodeARMVIXL* slow_path = nullptr;
// Return 0 if `obj` is null.
// avoid null check if we know obj is not null.
if (instruction->MustDoNullCheck()) {
DCHECK(!out.Is(obj));
__ Mov(out, 0);
__ CompareAndBranchIfZero(obj, final_label, /* far_target */ false);
}
switch (type_check_kind) {
case TypeCheckKind::kExactCheck: {
// /* HeapReference<Class> */ out = obj->klass_
GenerateReferenceLoadTwoRegisters(instruction,
out_loc,
obj_loc,
class_offset,
maybe_temp_loc,
kCompilerReadBarrierOption);
// Classes must be equal for the instanceof to succeed.
__ Cmp(out, cls);
// We speculatively set the result to false without changing the condition
// flags, which allows us to avoid some branching later.
__ Mov(LeaveFlags, out, 0);
// Since IT blocks longer than a 16-bit instruction are deprecated by ARMv8,
// we check that the output is in a low register, so that a 16-bit MOV
// encoding can be used.
if (out.IsLow()) {
// We use the scope because of the IT block that follows.
ExactAssemblyScope guard(GetVIXLAssembler(),
2 * vixl32::k16BitT32InstructionSizeInBytes,
CodeBufferCheckScope::kExactSize);
__ it(eq);
__ mov(eq, out, 1);
} else {
__ B(ne, final_label, /* far_target */ false);
__ Mov(out, 1);
}
break;
}
case TypeCheckKind::kAbstractClassCheck: {
// /* HeapReference<Class> */ out = obj->klass_
GenerateReferenceLoadTwoRegisters(instruction,
out_loc,
obj_loc,
class_offset,
maybe_temp_loc,
kCompilerReadBarrierOption);
// If the class is abstract, we eagerly fetch the super class of the
// object to avoid doing a comparison we know will fail.
vixl32::Label loop;
__ Bind(&loop);
// /* HeapReference<Class> */ out = out->super_class_
GenerateReferenceLoadOneRegister(instruction,
out_loc,
super_offset,
maybe_temp_loc,
kCompilerReadBarrierOption);
// If `out` is null, we use it for the result, and jump to the final label.
__ CompareAndBranchIfZero(out, final_label, /* far_target */ false);
__ Cmp(out, cls);
__ B(ne, &loop, /* far_target */ false);
__ Mov(out, 1);
break;
}
case TypeCheckKind::kClassHierarchyCheck: {
// /* HeapReference<Class> */ out = obj->klass_
GenerateReferenceLoadTwoRegisters(instruction,
out_loc,
obj_loc,
class_offset,
maybe_temp_loc,
kCompilerReadBarrierOption);
// Walk over the class hierarchy to find a match.
vixl32::Label loop, success;
__ Bind(&loop);
__ Cmp(out, cls);
__ B(eq, &success, /* far_target */ false);
// /* HeapReference<Class> */ out = out->super_class_
GenerateReferenceLoadOneRegister(instruction,
out_loc,
super_offset,
maybe_temp_loc,
kCompilerReadBarrierOption);
// This is essentially a null check, but it sets the condition flags to the
// proper value for the code that follows the loop, i.e. not `eq`.
__ Cmp(out, 1);
__ B(hs, &loop, /* far_target */ false);
// Since IT blocks longer than a 16-bit instruction are deprecated by ARMv8,
// we check that the output is in a low register, so that a 16-bit MOV
// encoding can be used.
if (out.IsLow()) {
// If `out` is null, we use it for the result, and the condition flags
// have already been set to `ne`, so the IT block that comes afterwards
// (and which handles the successful case) turns into a NOP (instead of
// overwriting `out`).
__ Bind(&success);
// We use the scope because of the IT block that follows.
ExactAssemblyScope guard(GetVIXLAssembler(),
2 * vixl32::k16BitT32InstructionSizeInBytes,
CodeBufferCheckScope::kExactSize);
// There is only one branch to the `success` label (which is bound to this
// IT block), and it has the same condition, `eq`, so in that case the MOV
// is executed.
__ it(eq);
__ mov(eq, out, 1);
} else {
// If `out` is null, we use it for the result, and jump to the final label.
__ B(final_label);
__ Bind(&success);
__ Mov(out, 1);
}
break;
}
case TypeCheckKind::kArrayObjectCheck: {
// /* HeapReference<Class> */ out = obj->klass_
GenerateReferenceLoadTwoRegisters(instruction,
out_loc,
obj_loc,
class_offset,
maybe_temp_loc,
kCompilerReadBarrierOption);
// Do an exact check.
vixl32::Label exact_check;
__ Cmp(out, cls);
__ B(eq, &exact_check, /* far_target */ false);
// Otherwise, we need to check that the object's class is a non-primitive array.
// /* HeapReference<Class> */ out = out->component_type_
GenerateReferenceLoadOneRegister(instruction,
out_loc,
component_offset,
maybe_temp_loc,
kCompilerReadBarrierOption);
// If `out` is null, we use it for the result, and jump to the final label.
__ CompareAndBranchIfZero(out, final_label, /* far_target */ false);
GetAssembler()->LoadFromOffset(kLoadUnsignedHalfword, out, out, primitive_offset);
static_assert(Primitive::kPrimNot == 0, "Expected 0 for kPrimNot");
__ Cmp(out, 0);
// We speculatively set the result to false without changing the condition
// flags, which allows us to avoid some branching later.
__ Mov(LeaveFlags, out, 0);
// Since IT blocks longer than a 16-bit instruction are deprecated by ARMv8,
// we check that the output is in a low register, so that a 16-bit MOV
// encoding can be used.
if (out.IsLow()) {
__ Bind(&exact_check);
// We use the scope because of the IT block that follows.
ExactAssemblyScope guard(GetVIXLAssembler(),
2 * vixl32::k16BitT32InstructionSizeInBytes,
CodeBufferCheckScope::kExactSize);
__ it(eq);
__ mov(eq, out, 1);
} else {
__ B(ne, final_label, /* far_target */ false);
__ Bind(&exact_check);
__ Mov(out, 1);
}
break;
}
case TypeCheckKind::kArrayCheck: {
// No read barrier since the slow path will retry upon failure.
// /* HeapReference<Class> */ out = obj->klass_
GenerateReferenceLoadTwoRegisters(instruction,
out_loc,
obj_loc,
class_offset,
maybe_temp_loc,
kWithoutReadBarrier);
__ Cmp(out, cls);
DCHECK(locations->OnlyCallsOnSlowPath());
slow_path = new (GetGraph()->GetArena()) TypeCheckSlowPathARMVIXL(instruction,
/* is_fatal */ false);
codegen_->AddSlowPath(slow_path);
__ B(ne, slow_path->GetEntryLabel());
__ Mov(out, 1);
break;
}
case TypeCheckKind::kUnresolvedCheck:
case TypeCheckKind::kInterfaceCheck: {
// Note that we indeed only call on slow path, but we always go
// into the slow path for the unresolved and interface check
// cases.
//
// We cannot directly call the InstanceofNonTrivial runtime
// entry point without resorting to a type checking slow path
// here (i.e. by calling InvokeRuntime directly), as it would
// require to assign fixed registers for the inputs of this
// HInstanceOf instruction (following the runtime calling
// convention), which might be cluttered by the potential first
// read barrier emission at the beginning of this method.
//
// TODO: Introduce a new runtime entry point taking the object
// to test (instead of its class) as argument, and let it deal
// with the read barrier issues. This will let us refactor this
// case of the `switch` code as it was previously (with a direct
// call to the runtime not using a type checking slow path).
// This should also be beneficial for the other cases above.
DCHECK(locations->OnlyCallsOnSlowPath());
slow_path = new (GetGraph()->GetArena()) TypeCheckSlowPathARMVIXL(instruction,
/* is_fatal */ false);
codegen_->AddSlowPath(slow_path);
__ B(slow_path->GetEntryLabel());
break;
}
}
if (done.IsReferenced()) {
__ Bind(&done);
}
if (slow_path != nullptr) {
__ Bind(slow_path->GetExitLabel());
}
}
void LocationsBuilderARMVIXL::VisitCheckCast(HCheckCast* instruction) {
LocationSummary::CallKind call_kind = LocationSummary::kNoCall;
bool throws_into_catch = instruction->CanThrowIntoCatchBlock();
TypeCheckKind type_check_kind = instruction->GetTypeCheckKind();
switch (type_check_kind) {
case TypeCheckKind::kExactCheck:
case TypeCheckKind::kAbstractClassCheck:
case TypeCheckKind::kClassHierarchyCheck:
case TypeCheckKind::kArrayObjectCheck:
call_kind = (throws_into_catch || kEmitCompilerReadBarrier) ?
LocationSummary::kCallOnSlowPath :
LocationSummary::kNoCall; // In fact, call on a fatal (non-returning) slow path.
break;
case TypeCheckKind::kArrayCheck:
case TypeCheckKind::kUnresolvedCheck:
case TypeCheckKind::kInterfaceCheck:
call_kind = LocationSummary::kCallOnSlowPath;
break;
}
LocationSummary* locations = new (GetGraph()->GetArena()) LocationSummary(instruction, call_kind);
locations->SetInAt(0, Location::RequiresRegister());
locations->SetInAt(1, Location::RequiresRegister());
locations->AddRegisterTemps(NumberOfCheckCastTemps(type_check_kind));
}
void InstructionCodeGeneratorARMVIXL::VisitCheckCast(HCheckCast* instruction) {
TypeCheckKind type_check_kind = instruction->GetTypeCheckKind();
LocationSummary* locations = instruction->GetLocations();
Location obj_loc = locations->InAt(0);
vixl32::Register obj = InputRegisterAt(instruction, 0);
vixl32::Register cls = InputRegisterAt(instruction, 1);
Location temp_loc = locations->GetTemp(0);
vixl32::Register temp = RegisterFrom(temp_loc);
const size_t num_temps = NumberOfCheckCastTemps(type_check_kind);
DCHECK_LE(num_temps, 3u);
Location maybe_temp2_loc = (num_temps >= 2) ? locations->GetTemp(1) : Location::NoLocation();
Location maybe_temp3_loc = (num_temps >= 3) ? locations->GetTemp(2) : Location::NoLocation();
const uint32_t class_offset = mirror::Object::ClassOffset().Int32Value();
const uint32_t super_offset = mirror::Class::SuperClassOffset().Int32Value();
const uint32_t component_offset = mirror::Class::ComponentTypeOffset().Int32Value();
const uint32_t primitive_offset = mirror::Class::PrimitiveTypeOffset().Int32Value();
const uint32_t iftable_offset = mirror::Class::IfTableOffset().Uint32Value();
const uint32_t array_length_offset = mirror::Array::LengthOffset().Uint32Value();
const uint32_t object_array_data_offset =
mirror::Array::DataOffset(kHeapReferenceSize).Uint32Value();
// Always false for read barriers since we may need to go to the entrypoint for non-fatal cases
// from false negatives. The false negatives may come from avoiding read barriers below. Avoiding
// read barriers is done for performance and code size reasons.
bool is_type_check_slow_path_fatal = false;
if (!kEmitCompilerReadBarrier) {
is_type_check_slow_path_fatal =
(type_check_kind == TypeCheckKind::kExactCheck ||
type_check_kind == TypeCheckKind::kAbstractClassCheck ||
type_check_kind == TypeCheckKind::kClassHierarchyCheck ||
type_check_kind == TypeCheckKind::kArrayObjectCheck) &&
!instruction->CanThrowIntoCatchBlock();
}
SlowPathCodeARMVIXL* type_check_slow_path =
new (GetGraph()->GetArena()) TypeCheckSlowPathARMVIXL(instruction,
is_type_check_slow_path_fatal);
codegen_->AddSlowPath(type_check_slow_path);
vixl32::Label done;
vixl32::Label* final_label = codegen_->GetFinalLabel(instruction, &done);
// Avoid null check if we know obj is not null.
if (instruction->MustDoNullCheck()) {
__ CompareAndBranchIfZero(obj, final_label, /* far_target */ false);
}
switch (type_check_kind) {
case TypeCheckKind::kExactCheck:
case TypeCheckKind::kArrayCheck: {
// /* HeapReference<Class> */ temp = obj->klass_
GenerateReferenceLoadTwoRegisters(instruction,
temp_loc,
obj_loc,
class_offset,
maybe_temp2_loc,
kWithoutReadBarrier);
__ Cmp(temp, cls);
// Jump to slow path for throwing the exception or doing a
// more involved array check.
__ B(ne, type_check_slow_path->GetEntryLabel());
break;
}
case TypeCheckKind::kAbstractClassCheck: {
// /* HeapReference<Class> */ temp = obj->klass_
GenerateReferenceLoadTwoRegisters(instruction,
temp_loc,
obj_loc,
class_offset,
maybe_temp2_loc,
kWithoutReadBarrier);
// If the class is abstract, we eagerly fetch the super class of the
// object to avoid doing a comparison we know will fail.
vixl32::Label loop;
__ Bind(&loop);
// /* HeapReference<Class> */ temp = temp->super_class_
GenerateReferenceLoadOneRegister(instruction,
temp_loc,
super_offset,
maybe_temp2_loc,
kWithoutReadBarrier);
// If the class reference currently in `temp` is null, jump to the slow path to throw the
// exception.
__ CompareAndBranchIfZero(temp, type_check_slow_path->GetEntryLabel());
// Otherwise, compare the classes.
__ Cmp(temp, cls);
__ B(ne, &loop, /* far_target */ false);
break;
}
case TypeCheckKind::kClassHierarchyCheck: {
// /* HeapReference<Class> */ temp = obj->klass_
GenerateReferenceLoadTwoRegisters(instruction,
temp_loc,
obj_loc,
class_offset,
maybe_temp2_loc,
kWithoutReadBarrier);
// Walk over the class hierarchy to find a match.
vixl32::Label loop;
__ Bind(&loop);
__ Cmp(temp, cls);
__ B(eq, final_label, /* far_target */ false);
// /* HeapReference<Class> */ temp = temp->super_class_
GenerateReferenceLoadOneRegister(instruction,
temp_loc,
super_offset,
maybe_temp2_loc,
kWithoutReadBarrier);
// If the class reference currently in `temp` is null, jump to the slow path to throw the
// exception.
__ CompareAndBranchIfZero(temp, type_check_slow_path->GetEntryLabel());
// Otherwise, jump to the beginning of the loop.
__ B(&loop);
break;
}
case TypeCheckKind::kArrayObjectCheck: {
// /* HeapReference<Class> */ temp = obj->klass_
GenerateReferenceLoadTwoRegisters(instruction,
temp_loc,
obj_loc,
class_offset,
maybe_temp2_loc,
kWithoutReadBarrier);
// Do an exact check.
__ Cmp(temp, cls);
__ B(eq, final_label, /* far_target */ false);
// Otherwise, we need to check that the object's class is a non-primitive array.
// /* HeapReference<Class> */ temp = temp->component_type_
GenerateReferenceLoadOneRegister(instruction,
temp_loc,
component_offset,
maybe_temp2_loc,
kWithoutReadBarrier);
// If the component type is null, jump to the slow path to throw the exception.
__ CompareAndBranchIfZero(temp, type_check_slow_path->GetEntryLabel());
// Otherwise,the object is indeed an array, jump to label `check_non_primitive_component_type`
// to further check that this component type is not a primitive type.
GetAssembler()->LoadFromOffset(kLoadUnsignedHalfword, temp, temp, primitive_offset);
static_assert(Primitive::kPrimNot == 0, "Expected 0 for art::Primitive::kPrimNot");
__ CompareAndBranchIfNonZero(temp, type_check_slow_path->GetEntryLabel());
break;
}
case TypeCheckKind::kUnresolvedCheck:
// We always go into the type check slow path for the unresolved check case.
// We cannot directly call the CheckCast runtime entry point
// without resorting to a type checking slow path here (i.e. by
// calling InvokeRuntime directly), as it would require to
// assign fixed registers for the inputs of this HInstanceOf
// instruction (following the runtime calling convention), which
// might be cluttered by the potential first read barrier
// emission at the beginning of this method.
__ B(type_check_slow_path->GetEntryLabel());
break;
case TypeCheckKind::kInterfaceCheck: {
// Avoid read barriers to improve performance of the fast path. We can not get false
// positives by doing this.
// /* HeapReference<Class> */ temp = obj->klass_
GenerateReferenceLoadTwoRegisters(instruction,
temp_loc,
obj_loc,
class_offset,
maybe_temp2_loc,
kWithoutReadBarrier);
// /* HeapReference<Class> */ temp = temp->iftable_
GenerateReferenceLoadTwoRegisters(instruction,
temp_loc,
temp_loc,
iftable_offset,
maybe_temp2_loc,
kWithoutReadBarrier);
// Iftable is never null.
__ Ldr(RegisterFrom(maybe_temp2_loc), MemOperand(temp, array_length_offset));
// Loop through the iftable and check if any class matches.
vixl32::Label start_loop;
__ Bind(&start_loop);
__ CompareAndBranchIfZero(RegisterFrom(maybe_temp2_loc),
type_check_slow_path->GetEntryLabel());
__ Ldr(RegisterFrom(maybe_temp3_loc), MemOperand(temp, object_array_data_offset));
GetAssembler()->MaybeUnpoisonHeapReference(RegisterFrom(maybe_temp3_loc));
// Go to next interface.
__ Add(temp, temp, Operand::From(2 * kHeapReferenceSize));
__ Sub(RegisterFrom(maybe_temp2_loc), RegisterFrom(maybe_temp2_loc), 2);
// Compare the classes and continue the loop if they do not match.
__ Cmp(cls, RegisterFrom(maybe_temp3_loc));
__ B(ne, &start_loop, /* far_target */ false);
break;
}
}
if (done.IsReferenced()) {
__ Bind(&done);
}
__ Bind(type_check_slow_path->GetExitLabel());
}
void LocationsBuilderARMVIXL::VisitMonitorOperation(HMonitorOperation* instruction) {
LocationSummary* locations =
new (GetGraph()->GetArena()) LocationSummary(instruction, LocationSummary::kCallOnMainOnly);
InvokeRuntimeCallingConventionARMVIXL calling_convention;
locations->SetInAt(0, LocationFrom(calling_convention.GetRegisterAt(0)));
}
void InstructionCodeGeneratorARMVIXL::VisitMonitorOperation(HMonitorOperation* instruction) {
codegen_->InvokeRuntime(instruction->IsEnter() ? kQuickLockObject : kQuickUnlockObject,
instruction,
instruction->GetDexPc());
if (instruction->IsEnter()) {
CheckEntrypointTypes<kQuickLockObject, void, mirror::Object*>();
} else {
CheckEntrypointTypes<kQuickUnlockObject, void, mirror::Object*>();
}
}
void LocationsBuilderARMVIXL::VisitAnd(HAnd* instruction) {
HandleBitwiseOperation(instruction, AND);
}
void LocationsBuilderARMVIXL::VisitOr(HOr* instruction) {
HandleBitwiseOperation(instruction, ORR);
}
void LocationsBuilderARMVIXL::VisitXor(HXor* instruction) {
HandleBitwiseOperation(instruction, EOR);
}
void LocationsBuilderARMVIXL::HandleBitwiseOperation(HBinaryOperation* instruction, Opcode opcode) {
LocationSummary* locations =
new (GetGraph()->GetArena()) LocationSummary(instruction, LocationSummary::kNoCall);
DCHECK(instruction->GetResultType() == Primitive::kPrimInt
|| instruction->GetResultType() == Primitive::kPrimLong);
// Note: GVN reorders commutative operations to have the constant on the right hand side.
locations->SetInAt(0, Location::RequiresRegister());
locations->SetInAt(1, ArmEncodableConstantOrRegister(instruction->InputAt(1), opcode));
locations->SetOut(Location::RequiresRegister(), Location::kNoOutputOverlap);
}
void InstructionCodeGeneratorARMVIXL::VisitAnd(HAnd* instruction) {
HandleBitwiseOperation(instruction);
}
void InstructionCodeGeneratorARMVIXL::VisitOr(HOr* instruction) {
HandleBitwiseOperation(instruction);
}
void InstructionCodeGeneratorARMVIXL::VisitXor(HXor* instruction) {
HandleBitwiseOperation(instruction);
}
void LocationsBuilderARMVIXL::VisitBitwiseNegatedRight(HBitwiseNegatedRight* instruction) {
LocationSummary* locations =
new (GetGraph()->GetArena()) LocationSummary(instruction, LocationSummary::kNoCall);
DCHECK(instruction->GetResultType() == Primitive::kPrimInt
|| instruction->GetResultType() == Primitive::kPrimLong);
locations->SetInAt(0, Location::RequiresRegister());
locations->SetInAt(1, Location::RequiresRegister());
locations->SetOut(Location::RequiresRegister(), Location::kNoOutputOverlap);
}
void InstructionCodeGeneratorARMVIXL::VisitBitwiseNegatedRight(HBitwiseNegatedRight* instruction) {
LocationSummary* locations = instruction->GetLocations();
Location first = locations->InAt(0);
Location second = locations->InAt(1);
Location out = locations->Out();
if (instruction->GetResultType() == Primitive::kPrimInt) {
vixl32::Register first_reg = RegisterFrom(first);
vixl32::Register second_reg = RegisterFrom(second);
vixl32::Register out_reg = RegisterFrom(out);
switch (instruction->GetOpKind()) {
case HInstruction::kAnd:
__ Bic(out_reg, first_reg, second_reg);
break;
case HInstruction::kOr:
__ Orn(out_reg, first_reg, second_reg);
break;
// There is no EON on arm.
case HInstruction::kXor:
default:
LOG(FATAL) << "Unexpected instruction " << instruction->DebugName();
UNREACHABLE();
}
return;
} else {
DCHECK_EQ(instruction->GetResultType(), Primitive::kPrimLong);
vixl32::Register first_low = LowRegisterFrom(first);
vixl32::Register first_high = HighRegisterFrom(first);
vixl32::Register second_low = LowRegisterFrom(second);
vixl32::Register second_high = HighRegisterFrom(second);
vixl32::Register out_low = LowRegisterFrom(out);
vixl32::Register out_high = HighRegisterFrom(out);
switch (instruction->GetOpKind()) {
case HInstruction::kAnd:
__ Bic(out_low, first_low, second_low);
__ Bic(out_high, first_high, second_high);
break;
case HInstruction::kOr:
__ Orn(out_low, first_low, second_low);
__ Orn(out_high, first_high, second_high);
break;
// There is no EON on arm.
case HInstruction::kXor:
default:
LOG(FATAL) << "Unexpected instruction " << instruction->DebugName();
UNREACHABLE();
}
}
}
void LocationsBuilderARMVIXL::VisitDataProcWithShifterOp(
HDataProcWithShifterOp* instruction) {
DCHECK(instruction->GetType() == Primitive::kPrimInt ||
instruction->GetType() == Primitive::kPrimLong);
LocationSummary* locations =
new (GetGraph()->GetArena()) LocationSummary(instruction, LocationSummary::kNoCall);
const bool overlap = instruction->GetType() == Primitive::kPrimLong &&
HDataProcWithShifterOp::IsExtensionOp(instruction->GetOpKind());
locations->SetInAt(0, Location::RequiresRegister());
locations->SetInAt(1, Location::RequiresRegister());
locations->SetOut(Location::RequiresRegister(),
overlap ? Location::kOutputOverlap : Location::kNoOutputOverlap);
}
void InstructionCodeGeneratorARMVIXL::VisitDataProcWithShifterOp(
HDataProcWithShifterOp* instruction) {
const LocationSummary* const locations = instruction->GetLocations();
const HInstruction::InstructionKind kind = instruction->GetInstrKind();
const HDataProcWithShifterOp::OpKind op_kind = instruction->GetOpKind();
if (instruction->GetType() == Primitive::kPrimInt) {
DCHECK(!HDataProcWithShifterOp::IsExtensionOp(op_kind));
const vixl32::Register second = instruction->InputAt(1)->GetType() == Primitive::kPrimLong
? LowRegisterFrom(locations->InAt(1))
: InputRegisterAt(instruction, 1);
GenerateDataProcInstruction(kind,
OutputRegister(instruction),
InputRegisterAt(instruction, 0),
Operand(second,
ShiftFromOpKind(op_kind),
instruction->GetShiftAmount()),
codegen_);
} else {
DCHECK_EQ(instruction->GetType(), Primitive::kPrimLong);
if (HDataProcWithShifterOp::IsExtensionOp(op_kind)) {
const vixl32::Register second = InputRegisterAt(instruction, 1);
DCHECK(!LowRegisterFrom(locations->Out()).Is(second));
GenerateDataProc(kind,
locations->Out(),
locations->InAt(0),
second,
Operand(second, ShiftType::ASR, 31),
codegen_);
} else {
GenerateLongDataProc(instruction, codegen_);
}
}
}
// TODO(VIXL): Remove optimizations in the helper when they are implemented in vixl.
void InstructionCodeGeneratorARMVIXL::GenerateAndConst(vixl32::Register out,
vixl32::Register first,
uint32_t value) {
// Optimize special cases for individual halfs of `and-long` (`and` is simplified earlier).
if (value == 0xffffffffu) {
if (!out.Is(first)) {
__ Mov(out, first);
}
return;
}
if (value == 0u) {
__ Mov(out, 0);
return;
}
if (GetAssembler()->ShifterOperandCanHold(AND, value)) {
__ And(out, first, value);
} else if (GetAssembler()->ShifterOperandCanHold(BIC, ~value)) {
__ Bic(out, first, ~value);
} else {
DCHECK(IsPowerOfTwo(value + 1));
__ Ubfx(out, first, 0, WhichPowerOf2(value + 1));
}
}
// TODO(VIXL): Remove optimizations in the helper when they are implemented in vixl.
void InstructionCodeGeneratorARMVIXL::GenerateOrrConst(vixl32::Register out,
vixl32::Register first,
uint32_t value) {
// Optimize special cases for individual halfs of `or-long` (`or` is simplified earlier).
if (value == 0u) {
if (!out.Is(first)) {
__ Mov(out, first);
}
return;
}
if (value == 0xffffffffu) {
__ Mvn(out, 0);
return;
}
if (GetAssembler()->ShifterOperandCanHold(ORR, value)) {
__ Orr(out, first, value);
} else {
DCHECK(GetAssembler()->ShifterOperandCanHold(ORN, ~value));
__ Orn(out, first, ~value);
}
}
// TODO(VIXL): Remove optimizations in the helper when they are implemented in vixl.
void InstructionCodeGeneratorARMVIXL::GenerateEorConst(vixl32::Register out,
vixl32::Register first,
uint32_t value) {
// Optimize special case for individual halfs of `xor-long` (`xor` is simplified earlier).
if (value == 0u) {
if (!out.Is(first)) {
__ Mov(out, first);
}
return;
}
__ Eor(out, first, value);
}
void InstructionCodeGeneratorARMVIXL::GenerateAddLongConst(Location out,
Location first,
uint64_t value) {
vixl32::Register out_low = LowRegisterFrom(out);
vixl32::Register out_high = HighRegisterFrom(out);
vixl32::Register first_low = LowRegisterFrom(first);
vixl32::Register first_high = HighRegisterFrom(first);
uint32_t value_low = Low32Bits(value);
uint32_t value_high = High32Bits(value);
if (value_low == 0u) {
if (!out_low.Is(first_low)) {
__ Mov(out_low, first_low);
}
__ Add(out_high, first_high, value_high);
return;
}
__ Adds(out_low, first_low, value_low);
if (GetAssembler()->ShifterOperandCanHold(ADC, value_high, kCcDontCare)) {
__ Adc(out_high, first_high, value_high);
} else if (GetAssembler()->ShifterOperandCanHold(SBC, ~value_high, kCcDontCare)) {
__ Sbc(out_high, first_high, ~value_high);
} else {
LOG(FATAL) << "Unexpected constant " << value_high;
UNREACHABLE();
}
}
void InstructionCodeGeneratorARMVIXL::HandleBitwiseOperation(HBinaryOperation* instruction) {
LocationSummary* locations = instruction->GetLocations();
Location first = locations->InAt(0);
Location second = locations->InAt(1);
Location out = locations->Out();
if (second.IsConstant()) {
uint64_t value = static_cast<uint64_t>(Int64FromConstant(second.GetConstant()));
uint32_t value_low = Low32Bits(value);
if (instruction->GetResultType() == Primitive::kPrimInt) {
vixl32::Register first_reg = InputRegisterAt(instruction, 0);
vixl32::Register out_reg = OutputRegister(instruction);
if (instruction->IsAnd()) {
GenerateAndConst(out_reg, first_reg, value_low);
} else if (instruction->IsOr()) {
GenerateOrrConst(out_reg, first_reg, value_low);
} else {
DCHECK(instruction->IsXor());
GenerateEorConst(out_reg, first_reg, value_low);
}
} else {
DCHECK_EQ(instruction->GetResultType(), Primitive::kPrimLong);
uint32_t value_high = High32Bits(value);
vixl32::Register first_low = LowRegisterFrom(first);
vixl32::Register first_high = HighRegisterFrom(first);
vixl32::Register out_low = LowRegisterFrom(out);
vixl32::Register out_high = HighRegisterFrom(out);
if (instruction->IsAnd()) {
GenerateAndConst(out_low, first_low, value_low);
GenerateAndConst(out_high, first_high, value_high);
} else if (instruction->IsOr()) {
GenerateOrrConst(out_low, first_low, value_low);
GenerateOrrConst(out_high, first_high, value_high);
} else {
DCHECK(instruction->IsXor());
GenerateEorConst(out_low, first_low, value_low);
GenerateEorConst(out_high, first_high, value_high);
}
}
return;
}
if (instruction->GetResultType() == Primitive::kPrimInt) {
vixl32::Register first_reg = InputRegisterAt(instruction, 0);
vixl32::Register second_reg = InputRegisterAt(instruction, 1);
vixl32::Register out_reg = OutputRegister(instruction);
if (instruction->IsAnd()) {
__ And(out_reg, first_reg, second_reg);
} else if (instruction->IsOr()) {
__ Orr(out_reg, first_reg, second_reg);
} else {
DCHECK(instruction->IsXor());
__ Eor(out_reg, first_reg, second_reg);
}
} else {
DCHECK_EQ(instruction->GetResultType(), Primitive::kPrimLong);
vixl32::Register first_low = LowRegisterFrom(first);
vixl32::Register first_high = HighRegisterFrom(first);
vixl32::Register second_low = LowRegisterFrom(second);
vixl32::Register second_high = HighRegisterFrom(second);
vixl32::Register out_low = LowRegisterFrom(out);
vixl32::Register out_high = HighRegisterFrom(out);
if (instruction->IsAnd()) {
__ And(out_low, first_low, second_low);
__ And(out_high, first_high, second_high);
} else if (instruction->IsOr()) {
__ Orr(out_low, first_low, second_low);
__ Orr(out_high, first_high, second_high);
} else {
DCHECK(instruction->IsXor());
__ Eor(out_low, first_low, second_low);
__ Eor(out_high, first_high, second_high);
}
}
}
void InstructionCodeGeneratorARMVIXL::GenerateReferenceLoadOneRegister(
HInstruction* instruction,
Location out,
uint32_t offset,
Location maybe_temp,
ReadBarrierOption read_barrier_option) {
vixl32::Register out_reg = RegisterFrom(out);
if (read_barrier_option == kWithReadBarrier) {
CHECK(kEmitCompilerReadBarrier);
DCHECK(maybe_temp.IsRegister()) << maybe_temp;
if (kUseBakerReadBarrier) {
// Load with fast path based Baker's read barrier.
// /* HeapReference<Object> */ out = *(out + offset)
codegen_->GenerateFieldLoadWithBakerReadBarrier(
instruction, out, out_reg, offset, maybe_temp, /* needs_null_check */ false);
} else {
// Load with slow path based read barrier.
// Save the value of `out` into `maybe_temp` before overwriting it
// in the following move operation, as we will need it for the
// read barrier below.
__ Mov(RegisterFrom(maybe_temp), out_reg);
// /* HeapReference<Object> */ out = *(out + offset)
GetAssembler()->LoadFromOffset(kLoadWord, out_reg, out_reg, offset);
codegen_->GenerateReadBarrierSlow(instruction, out, out, maybe_temp, offset);
}
} else {
// Plain load with no read barrier.
// /* HeapReference<Object> */ out = *(out + offset)
GetAssembler()->LoadFromOffset(kLoadWord, out_reg, out_reg, offset);
GetAssembler()->MaybeUnpoisonHeapReference(out_reg);
}
}
void InstructionCodeGeneratorARMVIXL::GenerateReferenceLoadTwoRegisters(
HInstruction* instruction,
Location out,
Location obj,
uint32_t offset,
Location maybe_temp,
ReadBarrierOption read_barrier_option) {
vixl32::Register out_reg = RegisterFrom(out);
vixl32::Register obj_reg = RegisterFrom(obj);
if (read_barrier_option == kWithReadBarrier) {
CHECK(kEmitCompilerReadBarrier);
if (kUseBakerReadBarrier) {
DCHECK(maybe_temp.IsRegister()) << maybe_temp;
// Load with fast path based Baker's read barrier.
// /* HeapReference<Object> */ out = *(obj + offset)
codegen_->GenerateFieldLoadWithBakerReadBarrier(
instruction, out, obj_reg, offset, maybe_temp, /* needs_null_check */ false);
} else {
// Load with slow path based read barrier.
// /* HeapReference<Object> */ out = *(obj + offset)
GetAssembler()->LoadFromOffset(kLoadWord, out_reg, obj_reg, offset);
codegen_->GenerateReadBarrierSlow(instruction, out, out, obj, offset);
}
} else {
// Plain load with no read barrier.
// /* HeapReference<Object> */ out = *(obj + offset)
GetAssembler()->LoadFromOffset(kLoadWord, out_reg, obj_reg, offset);
GetAssembler()->MaybeUnpoisonHeapReference(out_reg);
}
}
void InstructionCodeGeneratorARMVIXL::GenerateGcRootFieldLoad(
HInstruction* instruction,
Location root,
vixl32::Register obj,
uint32_t offset,
ReadBarrierOption read_barrier_option) {
vixl32::Register root_reg = RegisterFrom(root);
if (read_barrier_option == kWithReadBarrier) {
DCHECK(kEmitCompilerReadBarrier);
if (kUseBakerReadBarrier) {
// Fast path implementation of art::ReadBarrier::BarrierForRoot when
// Baker's read barrier are used.
if (kBakerReadBarrierLinkTimeThunksEnableForGcRoots &&
!Runtime::Current()->UseJitCompilation()) {
// Note that we do not actually check the value of `GetIsGcMarking()`
// to decide whether to mark the loaded GC root or not. Instead, we
// load into `temp` (actually kBakerCcEntrypointRegister) the read
// barrier mark introspection entrypoint. If `temp` is null, it means
// that `GetIsGcMarking()` is false, and vice versa.
//
// We use link-time generated thunks for the slow path. That thunk
// checks the reference and jumps to the entrypoint if needed.
//
// temp = Thread::Current()->pReadBarrierMarkIntrospection
// lr = &return_address;
// GcRoot<mirror::Object> root = *(obj+offset); // Original reference load.
// if (temp != nullptr) {
// goto gc_root_thunk<root_reg>(lr)
// }
// return_address:
UseScratchRegisterScope temps(GetVIXLAssembler());
ExcludeIPAndBakerCcEntrypointRegister(&temps, instruction);
bool narrow = CanEmitNarrowLdr(root_reg, obj, offset);
uint32_t custom_data = linker::Thumb2RelativePatcher::EncodeBakerReadBarrierGcRootData(
root_reg.GetCode(), narrow);
vixl32::Label* bne_label = codegen_->NewBakerReadBarrierPatch(custom_data);
// entrypoint_reg =
// Thread::Current()->pReadBarrierMarkReg12, i.e. pReadBarrierMarkIntrospection.
DCHECK_EQ(ip.GetCode(), 12u);
const int32_t entry_point_offset =
CodeGenerator::GetReadBarrierMarkEntryPointsOffset<kArmPointerSize>(ip.GetCode());
__ Ldr(kBakerCcEntrypointRegister, MemOperand(tr, entry_point_offset));
vixl::EmissionCheckScope guard(GetVIXLAssembler(),
4 * vixl32::kMaxInstructionSizeInBytes);
vixl32::Label return_address;
EmitAdrCode adr(GetVIXLAssembler(), lr, &return_address);
__ cmp(kBakerCcEntrypointRegister, Operand(0));
// Currently the offset is always within range. If that changes,
// we shall have to split the load the same way as for fields.
DCHECK_LT(offset, kReferenceLoadMinFarOffset);
ptrdiff_t old_offset = GetVIXLAssembler()->GetBuffer()->GetCursorOffset();
__ ldr(EncodingSize(narrow ? Narrow : Wide), root_reg, MemOperand(obj, offset));
EmitPlaceholderBne(codegen_, bne_label);
__ Bind(&return_address);
DCHECK_EQ(old_offset - GetVIXLAssembler()->GetBuffer()->GetCursorOffset(),
narrow ? BAKER_MARK_INTROSPECTION_GC_ROOT_LDR_NARROW_OFFSET
: BAKER_MARK_INTROSPECTION_GC_ROOT_LDR_WIDE_OFFSET);
} else {
// Note that we do not actually check the value of
// `GetIsGcMarking()` to decide whether to mark the loaded GC
// root or not. Instead, we load into `temp` the read barrier
// mark entry point corresponding to register `root`. If `temp`
// is null, it means that `GetIsGcMarking()` is false, and vice
// versa.
//
// temp = Thread::Current()->pReadBarrierMarkReg ## root.reg()
// GcRoot<mirror::Object> root = *(obj+offset); // Original reference load.
// if (temp != nullptr) { // <=> Thread::Current()->GetIsGcMarking()
// // Slow path.
// root = temp(root); // root = ReadBarrier::Mark(root); // Runtime entry point call.
// }
// Slow path marking the GC root `root`. The entrypoint will already be loaded in `temp`.
Location temp = LocationFrom(lr);
SlowPathCodeARMVIXL* slow_path =
new (GetGraph()->GetArena()) ReadBarrierMarkSlowPathARMVIXL(
instruction, root, /* entrypoint */ temp);
codegen_->AddSlowPath(slow_path);
// temp = Thread::Current()->pReadBarrierMarkReg ## root.reg()
const int32_t entry_point_offset =
CodeGenerator::GetReadBarrierMarkEntryPointsOffset<kArmPointerSize>(root.reg());
// Loading the entrypoint does not require a load acquire since it is only changed when
// threads are suspended or running a checkpoint.
GetAssembler()->LoadFromOffset(kLoadWord, RegisterFrom(temp), tr, entry_point_offset);
// /* GcRoot<mirror::Object> */ root = *(obj + offset)
GetAssembler()->LoadFromOffset(kLoadWord, root_reg, obj, offset);
static_assert(
sizeof(mirror::CompressedReference<mirror::Object>) == sizeof(GcRoot<mirror::Object>),
"art::mirror::CompressedReference<mirror::Object> and art::GcRoot<mirror::Object> "
"have different sizes.");
static_assert(sizeof(mirror::CompressedReference<mirror::Object>) == sizeof(int32_t),
"art::mirror::CompressedReference<mirror::Object> and int32_t "
"have different sizes.");
// The entrypoint is null when the GC is not marking, this prevents one load compared to
// checking GetIsGcMarking.
__ CompareAndBranchIfNonZero(RegisterFrom(temp), slow_path->GetEntryLabel());
__ Bind(slow_path->GetExitLabel());
}
} else {
// GC root loaded through a slow path for read barriers other
// than Baker's.
// /* GcRoot<mirror::Object>* */ root = obj + offset
__ Add(root_reg, obj, offset);
// /* mirror::Object* */ root = root->Read()
codegen_->GenerateReadBarrierForRootSlow(instruction, root, root);
}
} else {
// Plain GC root load with no read barrier.
// /* GcRoot<mirror::Object> */ root = *(obj + offset)
GetAssembler()->LoadFromOffset(kLoadWord, root_reg, obj, offset);
// Note that GC roots are not affected by heap poisoning, thus we
// do not have to unpoison `root_reg` here.
}
}
void CodeGeneratorARMVIXL::MaybeAddBakerCcEntrypointTempForFields(LocationSummary* locations) {
DCHECK(kEmitCompilerReadBarrier);
DCHECK(kUseBakerReadBarrier);
if (kBakerReadBarrierLinkTimeThunksEnableForFields) {
if (!Runtime::Current()->UseJitCompilation()) {
locations->AddTemp(Location::RegisterLocation(kBakerCcEntrypointRegister.GetCode()));
}
}
}
void CodeGeneratorARMVIXL::GenerateFieldLoadWithBakerReadBarrier(HInstruction* instruction,
Location ref,
vixl32::Register obj,
uint32_t offset,
Location temp,
bool needs_null_check) {
DCHECK(kEmitCompilerReadBarrier);
DCHECK(kUseBakerReadBarrier);
if (kBakerReadBarrierLinkTimeThunksEnableForFields &&
!Runtime::Current()->UseJitCompilation()) {
// Note that we do not actually check the value of `GetIsGcMarking()`
// to decide whether to mark the loaded reference or not. Instead, we
// load into `temp` (actually kBakerCcEntrypointRegister) the read
// barrier mark introspection entrypoint. If `temp` is null, it means
// that `GetIsGcMarking()` is false, and vice versa.
//
// We use link-time generated thunks for the slow path. That thunk checks
// the holder and jumps to the entrypoint if needed. If the holder is not
// gray, it creates a fake dependency and returns to the LDR instruction.
//
// temp = Thread::Current()->pReadBarrierMarkIntrospection
// lr = &gray_return_address;
// if (temp != nullptr) {
// goto field_thunk<holder_reg, base_reg>(lr)
// }
// not_gray_return_address:
// // Original reference load. If the offset is too large to fit
// // into LDR, we use an adjusted base register here.
// HeapReference<mirror::Object> reference = *(obj+offset);
// gray_return_address:
DCHECK_ALIGNED(offset, sizeof(mirror::HeapReference<mirror::Object>));
vixl32::Register ref_reg = RegisterFrom(ref, Primitive::kPrimNot);
bool narrow = CanEmitNarrowLdr(ref_reg, obj, offset);
vixl32::Register base = obj;
if (offset >= kReferenceLoadMinFarOffset) {
base = RegisterFrom(temp);
DCHECK(!base.Is(kBakerCcEntrypointRegister));
static_assert(IsPowerOfTwo(kReferenceLoadMinFarOffset), "Expecting a power of 2.");
__ Add(base, obj, Operand(offset & ~(kReferenceLoadMinFarOffset - 1u)));
offset &= (kReferenceLoadMinFarOffset - 1u);
// Use narrow LDR only for small offsets. Generating narrow encoding LDR for the large
// offsets with `(offset & (kReferenceLoadMinFarOffset - 1u)) < 32u` would most likely
// increase the overall code size when taking the generated thunks into account.
DCHECK(!narrow);
}
UseScratchRegisterScope temps(GetVIXLAssembler());
ExcludeIPAndBakerCcEntrypointRegister(&temps, instruction);
uint32_t custom_data = linker::Thumb2RelativePatcher::EncodeBakerReadBarrierFieldData(
base.GetCode(), obj.GetCode(), narrow);
vixl32::Label* bne_label = NewBakerReadBarrierPatch(custom_data);
// entrypoint_reg =
// Thread::Current()->pReadBarrierMarkReg12, i.e. pReadBarrierMarkIntrospection.
DCHECK_EQ(ip.GetCode(), 12u);
const int32_t entry_point_offset =
CodeGenerator::GetReadBarrierMarkEntryPointsOffset<kArmPointerSize>(ip.GetCode());
__ Ldr(kBakerCcEntrypointRegister, MemOperand(tr, entry_point_offset));
vixl::EmissionCheckScope guard(
GetVIXLAssembler(),
(kPoisonHeapReferences ? 5u : 4u) * vixl32::kMaxInstructionSizeInBytes);
vixl32::Label return_address;
EmitAdrCode adr(GetVIXLAssembler(), lr, &return_address);
__ cmp(kBakerCcEntrypointRegister, Operand(0));
EmitPlaceholderBne(this, bne_label);
ptrdiff_t old_offset = GetVIXLAssembler()->GetBuffer()->GetCursorOffset();
__ ldr(EncodingSize(narrow ? Narrow : Wide), ref_reg, MemOperand(base, offset));
if (needs_null_check) {
MaybeRecordImplicitNullCheck(instruction);
}
// Note: We need a specific width for the unpoisoning NEG.
if (kPoisonHeapReferences) {
if (narrow) {
// The only 16-bit encoding is T1 which sets flags outside IT block (i.e. RSBS, not RSB).
__ rsbs(EncodingSize(Narrow), ref_reg, ref_reg, Operand(0));
} else {
__ rsb(EncodingSize(Wide), ref_reg, ref_reg, Operand(0));
}
}
__ Bind(&return_address);
DCHECK_EQ(old_offset - GetVIXLAssembler()->GetBuffer()->GetCursorOffset(),
narrow ? BAKER_MARK_INTROSPECTION_FIELD_LDR_NARROW_OFFSET
: BAKER_MARK_INTROSPECTION_FIELD_LDR_WIDE_OFFSET);
return;
}
// /* HeapReference<Object> */ ref = *(obj + offset)
Location no_index = Location::NoLocation();
ScaleFactor no_scale_factor = TIMES_1;
GenerateReferenceLoadWithBakerReadBarrier(
instruction, ref, obj, offset, no_index, no_scale_factor, temp, needs_null_check);
}
void CodeGeneratorARMVIXL::GenerateArrayLoadWithBakerReadBarrier(HInstruction* instruction,
Location ref,
vixl32::Register obj,
uint32_t data_offset,
Location index,
Location temp,
bool needs_null_check) {
DCHECK(kEmitCompilerReadBarrier);
DCHECK(kUseBakerReadBarrier);
static_assert(
sizeof(mirror::HeapReference<mirror::Object>) == sizeof(int32_t),
"art::mirror::HeapReference<art::mirror::Object> and int32_t have different sizes.");
ScaleFactor scale_factor = TIMES_4;
if (kBakerReadBarrierLinkTimeThunksEnableForArrays &&
!Runtime::Current()->UseJitCompilation()) {
// Note that we do not actually check the value of `GetIsGcMarking()`
// to decide whether to mark the loaded reference or not. Instead, we
// load into `temp` (actually kBakerCcEntrypointRegister) the read
// barrier mark introspection entrypoint. If `temp` is null, it means
// that `GetIsGcMarking()` is false, and vice versa.
//
// We use link-time generated thunks for the slow path. That thunk checks
// the holder and jumps to the entrypoint if needed. If the holder is not
// gray, it creates a fake dependency and returns to the LDR instruction.
//
// temp = Thread::Current()->pReadBarrierMarkIntrospection
// lr = &gray_return_address;
// if (temp != nullptr) {
// goto field_thunk<holder_reg, base_reg>(lr)
// }
// not_gray_return_address:
// // Original reference load. If the offset is too large to fit
// // into LDR, we use an adjusted base register here.
// HeapReference<mirror::Object> reference = data[index];
// gray_return_address:
DCHECK(index.IsValid());
vixl32::Register index_reg = RegisterFrom(index, Primitive::kPrimInt);
vixl32::Register ref_reg = RegisterFrom(ref, Primitive::kPrimNot);
vixl32::Register data_reg = RegisterFrom(temp, Primitive::kPrimInt); // Raw pointer.
DCHECK(!data_reg.Is(kBakerCcEntrypointRegister));
UseScratchRegisterScope temps(GetVIXLAssembler());
ExcludeIPAndBakerCcEntrypointRegister(&temps, instruction);
uint32_t custom_data =
linker::Thumb2RelativePatcher::EncodeBakerReadBarrierArrayData(data_reg.GetCode());
vixl32::Label* bne_label = NewBakerReadBarrierPatch(custom_data);
// entrypoint_reg =
// Thread::Current()->pReadBarrierMarkReg16, i.e. pReadBarrierMarkIntrospection.
DCHECK_EQ(ip.GetCode(), 12u);
const int32_t entry_point_offset =
CodeGenerator::GetReadBarrierMarkEntryPointsOffset<kArmPointerSize>(ip.GetCode());
__ Ldr(kBakerCcEntrypointRegister, MemOperand(tr, entry_point_offset));
__ Add(data_reg, obj, Operand(data_offset));
vixl::EmissionCheckScope guard(
GetVIXLAssembler(),
(kPoisonHeapReferences ? 5u : 4u) * vixl32::kMaxInstructionSizeInBytes);
vixl32::Label return_address;
EmitAdrCode adr(GetVIXLAssembler(), lr, &return_address);
__ cmp(kBakerCcEntrypointRegister, Operand(0));
EmitPlaceholderBne(this, bne_label);
ptrdiff_t old_offset = GetVIXLAssembler()->GetBuffer()->GetCursorOffset();
__ ldr(ref_reg, MemOperand(data_reg, index_reg, vixl32::LSL, scale_factor));
DCHECK(!needs_null_check); // The thunk cannot handle the null check.
// Note: We need a Wide NEG for the unpoisoning.
if (kPoisonHeapReferences) {
__ rsb(EncodingSize(Wide), ref_reg, ref_reg, Operand(0));
}
__ Bind(&return_address);
DCHECK_EQ(old_offset - GetVIXLAssembler()->GetBuffer()->GetCursorOffset(),
BAKER_MARK_INTROSPECTION_ARRAY_LDR_OFFSET);
return;
}
// /* HeapReference<Object> */ ref =
// *(obj + data_offset + index * sizeof(HeapReference<Object>))
GenerateReferenceLoadWithBakerReadBarrier(
instruction, ref, obj, data_offset, index, scale_factor, temp, needs_null_check);
}
void CodeGeneratorARMVIXL::GenerateReferenceLoadWithBakerReadBarrier(HInstruction* instruction,
Location ref,
vixl32::Register obj,
uint32_t offset,
Location index,
ScaleFactor scale_factor,
Location temp,
bool needs_null_check) {
DCHECK(kEmitCompilerReadBarrier);
DCHECK(kUseBakerReadBarrier);
// Query `art::Thread::Current()->GetIsGcMarking()` to decide
// whether we need to enter the slow path to mark the reference.
// Then, in the slow path, check the gray bit in the lock word of
// the reference's holder (`obj`) to decide whether to mark `ref` or
// not.
//
// Note that we do not actually check the value of `GetIsGcMarking()`;
// instead, we load into `temp2` the read barrier mark entry point
// corresponding to register `ref`. If `temp2` is null, it means
// that `GetIsGcMarking()` is false, and vice versa.
//
// temp2 = Thread::Current()->pReadBarrierMarkReg ## root.reg()
// if (temp2 != nullptr) { // <=> Thread::Current()->GetIsGcMarking()
// // Slow path.
// uint32_t rb_state = Lockword(obj->monitor_).ReadBarrierState();
// lfence; // Load fence or artificial data dependency to prevent load-load reordering
// HeapReference<mirror::Object> ref = *src; // Original reference load.
// bool is_gray = (rb_state == ReadBarrier::GrayState());
// if (is_gray) {
// ref = temp2(ref); // ref = ReadBarrier::Mark(ref); // Runtime entry point call.
// }
// } else {
// HeapReference<mirror::Object> ref = *src; // Original reference load.
// }
vixl32::Register temp_reg = RegisterFrom(temp);
// Slow path marking the object `ref` when the GC is marking. The
// entrypoint will already be loaded in `temp2`.
Location temp2 = LocationFrom(lr);
SlowPathCodeARMVIXL* slow_path =
new (GetGraph()->GetArena()) LoadReferenceWithBakerReadBarrierSlowPathARMVIXL(
instruction,
ref,
obj,
offset,
index,
scale_factor,
needs_null_check,
temp_reg,
/* entrypoint */ temp2);
AddSlowPath(slow_path);
// temp2 = Thread::Current()->pReadBarrierMarkReg ## ref.reg()
const int32_t entry_point_offset =
CodeGenerator::GetReadBarrierMarkEntryPointsOffset<kArmPointerSize>(ref.reg());
// Loading the entrypoint does not require a load acquire since it is only changed when
// threads are suspended or running a checkpoint.
GetAssembler()->LoadFromOffset(kLoadWord, RegisterFrom(temp2), tr, entry_point_offset);
// The entrypoint is null when the GC is not marking, this prevents one load compared to
// checking GetIsGcMarking.
__ CompareAndBranchIfNonZero(RegisterFrom(temp2), slow_path->GetEntryLabel());
// Fast path: the GC is not marking: just load the reference.
GenerateRawReferenceLoad(instruction, ref, obj, offset, index, scale_factor, needs_null_check);
__ Bind(slow_path->GetExitLabel());
}
void CodeGeneratorARMVIXL::UpdateReferenceFieldWithBakerReadBarrier(HInstruction* instruction,
Location ref,
vixl32::Register obj,
Location field_offset,
Location temp,
bool needs_null_check,
vixl32::Register temp2) {
DCHECK(kEmitCompilerReadBarrier);
DCHECK(kUseBakerReadBarrier);
// Query `art::Thread::Current()->GetIsGcMarking()` to decide
// whether we need to enter the slow path to update the reference
// field within `obj`. Then, in the slow path, check the gray bit
// in the lock word of the reference's holder (`obj`) to decide
// whether to mark `ref` and update the field or not.
//
// Note that we do not actually check the value of `GetIsGcMarking()`;
// instead, we load into `temp3` the read barrier mark entry point
// corresponding to register `ref`. If `temp3` is null, it means
// that `GetIsGcMarking()` is false, and vice versa.
//
// temp3 = Thread::Current()->pReadBarrierMarkReg ## root.reg()
// if (temp3 != nullptr) { // <=> Thread::Current()->GetIsGcMarking()
// // Slow path.
// uint32_t rb_state = Lockword(obj->monitor_).ReadBarrierState();
// lfence; // Load fence or artificial data dependency to prevent load-load reordering
// HeapReference<mirror::Object> ref = *(obj + field_offset); // Reference load.
// bool is_gray = (rb_state == ReadBarrier::GrayState());
// if (is_gray) {
// old_ref = ref;
// ref = temp3(ref); // ref = ReadBarrier::Mark(ref); // Runtime entry point call.
// compareAndSwapObject(obj, field_offset, old_ref, ref);
// }
// }
vixl32::Register temp_reg = RegisterFrom(temp);
// Slow path updating the object reference at address `obj + field_offset`
// when the GC is marking. The entrypoint will already be loaded in `temp3`.
Location temp3 = LocationFrom(lr);
SlowPathCodeARMVIXL* slow_path =
new (GetGraph()->GetArena()) LoadReferenceWithBakerReadBarrierAndUpdateFieldSlowPathARMVIXL(
instruction,
ref,
obj,
/* offset */ 0u,
/* index */ field_offset,
/* scale_factor */ ScaleFactor::TIMES_1,
needs_null_check,
temp_reg,
temp2,
/* entrypoint */ temp3);
AddSlowPath(slow_path);
// temp3 = Thread::Current()->pReadBarrierMarkReg ## ref.reg()
const int32_t entry_point_offset =
CodeGenerator::GetReadBarrierMarkEntryPointsOffset<kArmPointerSize>(ref.reg());
// Loading the entrypoint does not require a load acquire since it is only changed when
// threads are suspended or running a checkpoint.
GetAssembler()->LoadFromOffset(kLoadWord, RegisterFrom(temp3), tr, entry_point_offset);
// The entrypoint is null when the GC is not marking, this prevents one load compared to
// checking GetIsGcMarking.
__ CompareAndBranchIfNonZero(RegisterFrom(temp3), slow_path->GetEntryLabel());
// Fast path: the GC is not marking: nothing to do (the field is
// up-to-date, and we don't need to load the reference).
__ Bind(slow_path->GetExitLabel());
}
void CodeGeneratorARMVIXL::GenerateRawReferenceLoad(HInstruction* instruction,
Location ref,
vixl::aarch32::Register obj,
uint32_t offset,
Location index,
ScaleFactor scale_factor,
bool needs_null_check) {
Primitive::Type type = Primitive::kPrimNot;
vixl32::Register ref_reg = RegisterFrom(ref, type);
// If needed, vixl::EmissionCheckScope guards are used to ensure
// that no pools are emitted between the load (macro) instruction
// and MaybeRecordImplicitNullCheck.
if (index.IsValid()) {
// Load types involving an "index": ArrayGet,
// UnsafeGetObject/UnsafeGetObjectVolatile and UnsafeCASObject
// intrinsics.
// /* HeapReference<mirror::Object> */ ref = *(obj + offset + (index << scale_factor))
if (index.IsConstant()) {
size_t computed_offset =
(Int32ConstantFrom(index) << scale_factor) + offset;
vixl::EmissionCheckScope guard(GetVIXLAssembler(), kMaxMacroInstructionSizeInBytes);
GetAssembler()->LoadFromOffset(kLoadWord, ref_reg, obj, computed_offset);
if (needs_null_check) {
MaybeRecordImplicitNullCheck(instruction);
}
} else {
// Handle the special case of the
// UnsafeGetObject/UnsafeGetObjectVolatile and UnsafeCASObject
// intrinsics, which use a register pair as index ("long
// offset"), of which only the low part contains data.
vixl32::Register index_reg = index.IsRegisterPair()
? LowRegisterFrom(index)
: RegisterFrom(index);
UseScratchRegisterScope temps(GetVIXLAssembler());
vixl32::Register temp = temps.Acquire();
__ Add(temp, obj, Operand(index_reg, ShiftType::LSL, scale_factor));
{
vixl::EmissionCheckScope guard(GetVIXLAssembler(), kMaxMacroInstructionSizeInBytes);
GetAssembler()->LoadFromOffset(kLoadWord, ref_reg, temp, offset);
if (needs_null_check) {
MaybeRecordImplicitNullCheck(instruction);
}
}
}
} else {
// /* HeapReference<mirror::Object> */ ref = *(obj + offset)
vixl::EmissionCheckScope guard(GetVIXLAssembler(), kMaxMacroInstructionSizeInBytes);
GetAssembler()->LoadFromOffset(kLoadWord, ref_reg, obj, offset);
if (needs_null_check) {
MaybeRecordImplicitNullCheck(instruction);
}
}
// Object* ref = ref_addr->AsMirrorPtr()
GetAssembler()->MaybeUnpoisonHeapReference(ref_reg);
}
void CodeGeneratorARMVIXL::GenerateReadBarrierSlow(HInstruction* instruction,
Location out,
Location ref,
Location obj,
uint32_t offset,
Location index) {
DCHECK(kEmitCompilerReadBarrier);
// Insert a slow path based read barrier *after* the reference load.
//
// If heap poisoning is enabled, the unpoisoning of the loaded
// reference will be carried out by the runtime within the slow
// path.
//
// Note that `ref` currently does not get unpoisoned (when heap
// poisoning is enabled), which is alright as the `ref` argument is
// not used by the artReadBarrierSlow entry point.
//
// TODO: Unpoison `ref` when it is used by artReadBarrierSlow.
SlowPathCodeARMVIXL* slow_path = new (GetGraph()->GetArena())
ReadBarrierForHeapReferenceSlowPathARMVIXL(instruction, out, ref, obj, offset, index);
AddSlowPath(slow_path);
__ B(slow_path->GetEntryLabel());
__ Bind(slow_path->GetExitLabel());
}
void CodeGeneratorARMVIXL::MaybeGenerateReadBarrierSlow(HInstruction* instruction,
Location out,
Location ref,
Location obj,
uint32_t offset,
Location index) {
if (kEmitCompilerReadBarrier) {
// Baker's read barriers shall be handled by the fast path
// (CodeGeneratorARM::GenerateReferenceLoadWithBakerReadBarrier).
DCHECK(!kUseBakerReadBarrier);
// If heap poisoning is enabled, unpoisoning will be taken care of
// by the runtime within the slow path.
GenerateReadBarrierSlow(instruction, out, ref, obj, offset, index);
} else if (kPoisonHeapReferences) {
GetAssembler()->UnpoisonHeapReference(RegisterFrom(out));
}
}
void CodeGeneratorARMVIXL::GenerateReadBarrierForRootSlow(HInstruction* instruction,
Location out,
Location root) {
DCHECK(kEmitCompilerReadBarrier);
// Insert a slow path based read barrier *after* the GC root load.
//
// Note that GC roots are not affected by heap poisoning, so we do
// not need to do anything special for this here.
SlowPathCodeARMVIXL* slow_path =
new (GetGraph()->GetArena()) ReadBarrierForRootSlowPathARMVIXL(instruction, out, root);
AddSlowPath(slow_path);
__ B(slow_path->GetEntryLabel());
__ Bind(slow_path->GetExitLabel());
}
// Check if the desired_dispatch_info is supported. If it is, return it,
// otherwise return a fall-back info that should be used instead.
HInvokeStaticOrDirect::DispatchInfo CodeGeneratorARMVIXL::GetSupportedInvokeStaticOrDirectDispatch(
const HInvokeStaticOrDirect::DispatchInfo& desired_dispatch_info,
HInvokeStaticOrDirect* invoke ATTRIBUTE_UNUSED) {
return desired_dispatch_info;
}
vixl32::Register CodeGeneratorARMVIXL::GetInvokeStaticOrDirectExtraParameter(
HInvokeStaticOrDirect* invoke, vixl32::Register temp) {
DCHECK_EQ(invoke->InputCount(), invoke->GetNumberOfArguments() + 1u);
Location location = invoke->GetLocations()->InAt(invoke->GetSpecialInputIndex());
if (!invoke->GetLocations()->Intrinsified()) {
return RegisterFrom(location);
}
// For intrinsics we allow any location, so it may be on the stack.
if (!location.IsRegister()) {
GetAssembler()->LoadFromOffset(kLoadWord, temp, sp, location.GetStackIndex());
return temp;
}
// For register locations, check if the register was saved. If so, get it from the stack.
// Note: There is a chance that the register was saved but not overwritten, so we could
// save one load. However, since this is just an intrinsic slow path we prefer this
// simple and more robust approach rather that trying to determine if that's the case.
SlowPathCode* slow_path = GetCurrentSlowPath();
if (slow_path != nullptr && slow_path->IsCoreRegisterSaved(RegisterFrom(location).GetCode())) {
int stack_offset = slow_path->GetStackOffsetOfCoreRegister(RegisterFrom(location).GetCode());
GetAssembler()->LoadFromOffset(kLoadWord, temp, sp, stack_offset);
return temp;
}
return RegisterFrom(location);
}
void CodeGeneratorARMVIXL::GenerateStaticOrDirectCall(
HInvokeStaticOrDirect* invoke, Location temp, SlowPathCode* slow_path) {
Location callee_method = temp; // For all kinds except kRecursive, callee will be in temp.
switch (invoke->GetMethodLoadKind()) {
case HInvokeStaticOrDirect::MethodLoadKind::kStringInit: {
uint32_t offset =
GetThreadOffset<kArmPointerSize>(invoke->GetStringInitEntryPoint()).Int32Value();
// temp = thread->string_init_entrypoint
GetAssembler()->LoadFromOffset(kLoadWord, RegisterFrom(temp), tr, offset);
break;
}
case HInvokeStaticOrDirect::MethodLoadKind::kRecursive:
callee_method = invoke->GetLocations()->InAt(invoke->GetSpecialInputIndex());
break;
case HInvokeStaticOrDirect::MethodLoadKind::kBootImageLinkTimePcRelative: {
DCHECK(GetCompilerOptions().IsBootImage());
PcRelativePatchInfo* labels = NewPcRelativeMethodPatch(invoke->GetTargetMethod());
vixl32::Register temp_reg = RegisterFrom(temp);
EmitMovwMovtPlaceholder(labels, temp_reg);
break;
}
case HInvokeStaticOrDirect::MethodLoadKind::kDirectAddress:
__ Mov(RegisterFrom(temp), Operand::From(invoke->GetMethodAddress()));
break;
case HInvokeStaticOrDirect::MethodLoadKind::kBssEntry: {
PcRelativePatchInfo* labels = NewMethodBssEntryPatch(
MethodReference(&GetGraph()->GetDexFile(), invoke->GetDexMethodIndex()));
vixl32::Register temp_reg = RegisterFrom(temp);
EmitMovwMovtPlaceholder(labels, temp_reg);
GetAssembler()->LoadFromOffset(kLoadWord, temp_reg, temp_reg, /* offset*/ 0);
break;
}
case HInvokeStaticOrDirect::MethodLoadKind::kRuntimeCall: {
GenerateInvokeStaticOrDirectRuntimeCall(invoke, temp, slow_path);
return; // No code pointer retrieval; the runtime performs the call directly.
}
}
switch (invoke->GetCodePtrLocation()) {
case HInvokeStaticOrDirect::CodePtrLocation::kCallSelf:
{
// Use a scope to help guarantee that `RecordPcInfo()` records the correct pc.
ExactAssemblyScope aas(GetVIXLAssembler(),
vixl32::k32BitT32InstructionSizeInBytes,
CodeBufferCheckScope::kMaximumSize);
__ bl(GetFrameEntryLabel());
RecordPcInfo(invoke, invoke->GetDexPc(), slow_path);
}
break;
case HInvokeStaticOrDirect::CodePtrLocation::kCallArtMethod:
// LR = callee_method->entry_point_from_quick_compiled_code_
GetAssembler()->LoadFromOffset(
kLoadWord,
lr,
RegisterFrom(callee_method),
ArtMethod::EntryPointFromQuickCompiledCodeOffset(kArmPointerSize).Int32Value());
{
// Use a scope to help guarantee that `RecordPcInfo()` records the correct pc.
// blx in T32 has only 16bit encoding that's why a stricter check for the scope is used.
ExactAssemblyScope aas(GetVIXLAssembler(),
vixl32::k16BitT32InstructionSizeInBytes,
CodeBufferCheckScope::kExactSize);
// LR()
__ blx(lr);
RecordPcInfo(invoke, invoke->GetDexPc(), slow_path);
}
break;
}
DCHECK(!IsLeafMethod());
}
void CodeGeneratorARMVIXL::GenerateVirtualCall(
HInvokeVirtual* invoke, Location temp_location, SlowPathCode* slow_path) {
vixl32::Register temp = RegisterFrom(temp_location);
uint32_t method_offset = mirror::Class::EmbeddedVTableEntryOffset(
invoke->GetVTableIndex(), kArmPointerSize).Uint32Value();
// Use the calling convention instead of the location of the receiver, as
// intrinsics may have put the receiver in a different register. In the intrinsics
// slow path, the arguments have been moved to the right place, so here we are
// guaranteed that the receiver is the first register of the calling convention.
InvokeDexCallingConventionARMVIXL calling_convention;
vixl32::Register receiver = calling_convention.GetRegisterAt(0);
uint32_t class_offset = mirror::Object::ClassOffset().Int32Value();
{
// Make sure the pc is recorded immediately after the `ldr` instruction.
ExactAssemblyScope aas(GetVIXLAssembler(),
vixl32::kMaxInstructionSizeInBytes,
CodeBufferCheckScope::kMaximumSize);
// /* HeapReference<Class> */ temp = receiver->klass_
__ ldr(temp, MemOperand(receiver, class_offset));
MaybeRecordImplicitNullCheck(invoke);
}
// Instead of simply (possibly) unpoisoning `temp` here, we should
// emit a read barrier for the previous class reference load.
// However this is not required in practice, as this is an
// intermediate/temporary reference and because the current
// concurrent copying collector keeps the from-space memory
// intact/accessible until the end of the marking phase (the
// concurrent copying collector may not in the future).
GetAssembler()->MaybeUnpoisonHeapReference(temp);
// temp = temp->GetMethodAt(method_offset);
uint32_t entry_point = ArtMethod::EntryPointFromQuickCompiledCodeOffset(
kArmPointerSize).Int32Value();
GetAssembler()->LoadFromOffset(kLoadWord, temp, temp, method_offset);
// LR = temp->GetEntryPoint();
GetAssembler()->LoadFromOffset(kLoadWord, lr, temp, entry_point);
{
// Use a scope to help guarantee that `RecordPcInfo()` records the correct pc.
// blx in T32 has only 16bit encoding that's why a stricter check for the scope is used.
ExactAssemblyScope aas(GetVIXLAssembler(),
vixl32::k16BitT32InstructionSizeInBytes,
CodeBufferCheckScope::kExactSize);
// LR();
__ blx(lr);
RecordPcInfo(invoke, invoke->GetDexPc(), slow_path);
}
}
CodeGeneratorARMVIXL::PcRelativePatchInfo* CodeGeneratorARMVIXL::NewPcRelativeMethodPatch(
MethodReference target_method) {
return NewPcRelativePatch(*target_method.dex_file,
target_method.dex_method_index,
&pc_relative_method_patches_);
}
CodeGeneratorARMVIXL::PcRelativePatchInfo* CodeGeneratorARMVIXL::NewMethodBssEntryPatch(
MethodReference target_method) {
return NewPcRelativePatch(*target_method.dex_file,
target_method.dex_method_index,
&method_bss_entry_patches_);
}
CodeGeneratorARMVIXL::PcRelativePatchInfo* CodeGeneratorARMVIXL::NewPcRelativeTypePatch(
const DexFile& dex_file, dex::TypeIndex type_index) {
return NewPcRelativePatch(dex_file, type_index.index_, &pc_relative_type_patches_);
}
CodeGeneratorARMVIXL::PcRelativePatchInfo* CodeGeneratorARMVIXL::NewTypeBssEntryPatch(
const DexFile& dex_file, dex::TypeIndex type_index) {
return NewPcRelativePatch(dex_file, type_index.index_, &type_bss_entry_patches_);
}
CodeGeneratorARMVIXL::PcRelativePatchInfo* CodeGeneratorARMVIXL::NewPcRelativeStringPatch(
const DexFile& dex_file, dex::StringIndex string_index) {
return NewPcRelativePatch(dex_file, string_index.index_, &pc_relative_string_patches_);
}
CodeGeneratorARMVIXL::PcRelativePatchInfo* CodeGeneratorARMVIXL::NewPcRelativePatch(
const DexFile& dex_file, uint32_t offset_or_index, ArenaDeque<PcRelativePatchInfo>* patches) {
patches->emplace_back(dex_file, offset_or_index);
return &patches->back();
}
vixl::aarch32::Label* CodeGeneratorARMVIXL::NewBakerReadBarrierPatch(uint32_t custom_data) {
baker_read_barrier_patches_.emplace_back(custom_data);
return &baker_read_barrier_patches_.back().label;
}
VIXLUInt32Literal* CodeGeneratorARMVIXL::DeduplicateBootImageAddressLiteral(uint32_t address) {
return DeduplicateUint32Literal(dchecked_integral_cast<uint32_t>(address), &uint32_literals_);
}
VIXLUInt32Literal* CodeGeneratorARMVIXL::DeduplicateJitStringLiteral(
const DexFile& dex_file,
dex::StringIndex string_index,
Handle<mirror::String> handle) {
jit_string_roots_.Overwrite(StringReference(&dex_file, string_index),
reinterpret_cast64<uint64_t>(handle.GetReference()));
return jit_string_patches_.GetOrCreate(
StringReference(&dex_file, string_index),
[this]() {
return GetAssembler()->CreateLiteralDestroyedWithPool<uint32_t>(/* placeholder */ 0u);
});
}
VIXLUInt32Literal* CodeGeneratorARMVIXL::DeduplicateJitClassLiteral(const DexFile& dex_file,
dex::TypeIndex type_index,
Handle<mirror::Class> handle) {
jit_class_roots_.Overwrite(TypeReference(&dex_file, type_index),
reinterpret_cast64<uint64_t>(handle.GetReference()));
return jit_class_patches_.GetOrCreate(
TypeReference(&dex_file, type_index),
[this]() {
return GetAssembler()->CreateLiteralDestroyedWithPool<uint32_t>(/* placeholder */ 0u);
});
}
template <LinkerPatch (*Factory)(size_t, const DexFile*, uint32_t, uint32_t)>
inline void CodeGeneratorARMVIXL::EmitPcRelativeLinkerPatches(
const ArenaDeque<PcRelativePatchInfo>& infos,
ArenaVector<LinkerPatch>* linker_patches) {
for (const PcRelativePatchInfo& info : infos) {
const DexFile& dex_file = info.target_dex_file;
size_t offset_or_index = info.offset_or_index;
DCHECK(info.add_pc_label.IsBound());
uint32_t add_pc_offset = dchecked_integral_cast<uint32_t>(info.add_pc_label.GetLocation());
// Add MOVW patch.
DCHECK(info.movw_label.IsBound());
uint32_t movw_offset = dchecked_integral_cast<uint32_t>(info.movw_label.GetLocation());
linker_patches->push_back(Factory(movw_offset, &dex_file, add_pc_offset, offset_or_index));
// Add MOVT patch.
DCHECK(info.movt_label.IsBound());
uint32_t movt_offset = dchecked_integral_cast<uint32_t>(info.movt_label.GetLocation());
linker_patches->push_back(Factory(movt_offset, &dex_file, add_pc_offset, offset_or_index));
}
}
void CodeGeneratorARMVIXL::EmitLinkerPatches(ArenaVector<LinkerPatch>* linker_patches) {
DCHECK(linker_patches->empty());
size_t size =
/* MOVW+MOVT for each entry */ 2u * pc_relative_method_patches_.size() +
/* MOVW+MOVT for each entry */ 2u * method_bss_entry_patches_.size() +
/* MOVW+MOVT for each entry */ 2u * pc_relative_type_patches_.size() +
/* MOVW+MOVT for each entry */ 2u * type_bss_entry_patches_.size() +
/* MOVW+MOVT for each entry */ 2u * pc_relative_string_patches_.size() +
baker_read_barrier_patches_.size();
linker_patches->reserve(size);
if (GetCompilerOptions().IsBootImage()) {
EmitPcRelativeLinkerPatches<LinkerPatch::RelativeMethodPatch>(pc_relative_method_patches_,
linker_patches);
EmitPcRelativeLinkerPatches<LinkerPatch::RelativeTypePatch>(pc_relative_type_patches_,
linker_patches);
EmitPcRelativeLinkerPatches<LinkerPatch::RelativeStringPatch>(pc_relative_string_patches_,
linker_patches);
} else {
DCHECK(pc_relative_method_patches_.empty());
DCHECK(pc_relative_type_patches_.empty());
EmitPcRelativeLinkerPatches<LinkerPatch::StringBssEntryPatch>(pc_relative_string_patches_,
linker_patches);
}
EmitPcRelativeLinkerPatches<LinkerPatch::MethodBssEntryPatch>(method_bss_entry_patches_,
linker_patches);
EmitPcRelativeLinkerPatches<LinkerPatch::TypeBssEntryPatch>(type_bss_entry_patches_,
linker_patches);
for (const BakerReadBarrierPatchInfo& info : baker_read_barrier_patches_) {
linker_patches->push_back(LinkerPatch::BakerReadBarrierBranchPatch(info.label.GetLocation(),
info.custom_data));
}
DCHECK_EQ(size, linker_patches->size());
}
VIXLUInt32Literal* CodeGeneratorARMVIXL::DeduplicateUint32Literal(
uint32_t value,
Uint32ToLiteralMap* map) {
return map->GetOrCreate(
value,
[this, value]() {
return GetAssembler()->CreateLiteralDestroyedWithPool<uint32_t>(/* placeholder */ value);
});
}
void LocationsBuilderARMVIXL::VisitMultiplyAccumulate(HMultiplyAccumulate* instr) {
LocationSummary* locations =
new (GetGraph()->GetArena()) LocationSummary(instr, LocationSummary::kNoCall);
locations->SetInAt(HMultiplyAccumulate::kInputAccumulatorIndex,
Location::RequiresRegister());
locations->SetInAt(HMultiplyAccumulate::kInputMulLeftIndex, Location::RequiresRegister());
locations->SetInAt(HMultiplyAccumulate::kInputMulRightIndex, Location::RequiresRegister());
locations->SetOut(Location::RequiresRegister(), Location::kNoOutputOverlap);
}
void InstructionCodeGeneratorARMVIXL::VisitMultiplyAccumulate(HMultiplyAccumulate* instr) {
vixl32::Register res = OutputRegister(instr);
vixl32::Register accumulator =
InputRegisterAt(instr, HMultiplyAccumulate::kInputAccumulatorIndex);
vixl32::Register mul_left =
InputRegisterAt(instr, HMultiplyAccumulate::kInputMulLeftIndex);
vixl32::Register mul_right =
InputRegisterAt(instr, HMultiplyAccumulate::kInputMulRightIndex);
if (instr->GetOpKind() == HInstruction::kAdd) {
__ Mla(res, mul_left, mul_right, accumulator);
} else {
__ Mls(res, mul_left, mul_right, accumulator);
}
}
void LocationsBuilderARMVIXL::VisitBoundType(HBoundType* instruction ATTRIBUTE_UNUSED) {
// Nothing to do, this should be removed during prepare for register allocator.
LOG(FATAL) << "Unreachable";
}
void InstructionCodeGeneratorARMVIXL::VisitBoundType(HBoundType* instruction ATTRIBUTE_UNUSED) {
// Nothing to do, this should be removed during prepare for register allocator.
LOG(FATAL) << "Unreachable";
}
// Simple implementation of packed switch - generate cascaded compare/jumps.
void LocationsBuilderARMVIXL::VisitPackedSwitch(HPackedSwitch* switch_instr) {
LocationSummary* locations =
new (GetGraph()->GetArena()) LocationSummary(switch_instr, LocationSummary::kNoCall);
locations->SetInAt(0, Location::RequiresRegister());
if (switch_instr->GetNumEntries() > kPackedSwitchCompareJumpThreshold &&
codegen_->GetAssembler()->GetVIXLAssembler()->IsUsingT32()) {
locations->AddTemp(Location::RequiresRegister()); // We need a temp for the table base.
if (switch_instr->GetStartValue() != 0) {
locations->AddTemp(Location::RequiresRegister()); // We need a temp for the bias.
}
}
}
// TODO(VIXL): Investigate and reach the parity with old arm codegen.
void InstructionCodeGeneratorARMVIXL::VisitPackedSwitch(HPackedSwitch* switch_instr) {
int32_t lower_bound = switch_instr->GetStartValue();
uint32_t num_entries = switch_instr->GetNumEntries();
LocationSummary* locations = switch_instr->GetLocations();
vixl32::Register value_reg = InputRegisterAt(switch_instr, 0);
HBasicBlock* default_block = switch_instr->GetDefaultBlock();
if (num_entries <= kPackedSwitchCompareJumpThreshold ||
!codegen_->GetAssembler()->GetVIXLAssembler()->IsUsingT32()) {
// Create a series of compare/jumps.
UseScratchRegisterScope temps(GetVIXLAssembler());
vixl32::Register temp_reg = temps.Acquire();
// Note: It is fine for the below AddConstantSetFlags() using IP register to temporarily store
// the immediate, because IP is used as the destination register. For the other
// AddConstantSetFlags() and GenerateCompareWithImmediate(), the immediate values are constant,
// and they can be encoded in the instruction without making use of IP register.
__ Adds(temp_reg, value_reg, -lower_bound);
const ArenaVector<HBasicBlock*>& successors = switch_instr->GetBlock()->GetSuccessors();
// Jump to successors[0] if value == lower_bound.
__ B(eq, codegen_->GetLabelOf(successors[0]));
int32_t last_index = 0;
for (; num_entries - last_index > 2; last_index += 2) {
__ Adds(temp_reg, temp_reg, -2);
// Jump to successors[last_index + 1] if value < case_value[last_index + 2].
__ B(lo, codegen_->GetLabelOf(successors[last_index + 1]));
// Jump to successors[last_index + 2] if value == case_value[last_index + 2].
__ B(eq, codegen_->GetLabelOf(successors[last_index + 2]));
}
if (num_entries - last_index == 2) {
// The last missing case_value.
__ Cmp(temp_reg, 1);
__ B(eq, codegen_->GetLabelOf(successors[last_index + 1]));
}
// And the default for any other value.
if (!codegen_->GoesToNextBlock(switch_instr->GetBlock(), default_block)) {
__ B(codegen_->GetLabelOf(default_block));
}
} else {
// Create a table lookup.
vixl32::Register table_base = RegisterFrom(locations->GetTemp(0));
JumpTableARMVIXL* jump_table = codegen_->CreateJumpTable(switch_instr);
// Remove the bias.
vixl32::Register key_reg;
if (lower_bound != 0) {
key_reg = RegisterFrom(locations->GetTemp(1));
__ Sub(key_reg, value_reg, lower_bound);
} else {
key_reg = value_reg;
}
// Check whether the value is in the table, jump to default block if not.
__ Cmp(key_reg, num_entries - 1);
__ B(hi, codegen_->GetLabelOf(default_block));
UseScratchRegisterScope temps(GetVIXLAssembler());
vixl32::Register jump_offset = temps.Acquire();
// Load jump offset from the table.
{
const size_t jump_size = switch_instr->GetNumEntries() * sizeof(int32_t);
ExactAssemblyScope aas(GetVIXLAssembler(),
(vixl32::kMaxInstructionSizeInBytes * 4) + jump_size,
CodeBufferCheckScope::kMaximumSize);
__ adr(table_base, jump_table->GetTableStartLabel());
__ ldr(jump_offset, MemOperand(table_base, key_reg, vixl32::LSL, 2));
// Jump to target block by branching to table_base(pc related) + offset.
vixl32::Register target_address = table_base;
__ add(target_address, table_base, jump_offset);
__ bx(target_address);
jump_table->EmitTable(codegen_);
}
}
}
// Copy the result of a call into the given target.
void CodeGeneratorARMVIXL::MoveFromReturnRegister(Location trg, Primitive::Type type) {
if (!trg.IsValid()) {
DCHECK_EQ(type, Primitive::kPrimVoid);
return;
}
DCHECK_NE(type, Primitive::kPrimVoid);
Location return_loc = InvokeDexCallingConventionVisitorARMVIXL().GetReturnLocation(type);
if (return_loc.Equals(trg)) {
return;
}
// TODO: Consider pairs in the parallel move resolver, then this could be nicely merged
// with the last branch.
if (type == Primitive::kPrimLong) {
TODO_VIXL32(FATAL);
} else if (type == Primitive::kPrimDouble) {
TODO_VIXL32(FATAL);
} else {
// Let the parallel move resolver take care of all of this.
HParallelMove parallel_move(GetGraph()->GetArena());
parallel_move.AddMove(return_loc, trg, type, nullptr);
GetMoveResolver()->EmitNativeCode(&parallel_move);
}
}
void LocationsBuilderARMVIXL::VisitClassTableGet(HClassTableGet* instruction) {
LocationSummary* locations =
new (GetGraph()->GetArena()) LocationSummary(instruction, LocationSummary::kNoCall);
locations->SetInAt(0, Location::RequiresRegister());
locations->SetOut(Location::RequiresRegister());
}
void InstructionCodeGeneratorARMVIXL::VisitClassTableGet(HClassTableGet* instruction) {
if (instruction->GetTableKind() == HClassTableGet::TableKind::kVTable) {
uint32_t method_offset = mirror::Class::EmbeddedVTableEntryOffset(
instruction->GetIndex(), kArmPointerSize).SizeValue();
GetAssembler()->LoadFromOffset(kLoadWord,
OutputRegister(instruction),
InputRegisterAt(instruction, 0),
method_offset);
} else {
uint32_t method_offset = static_cast<uint32_t>(ImTable::OffsetOfElement(
instruction->GetIndex(), kArmPointerSize));
GetAssembler()->LoadFromOffset(kLoadWord,
OutputRegister(instruction),
InputRegisterAt(instruction, 0),
mirror::Class::ImtPtrOffset(kArmPointerSize).Uint32Value());
GetAssembler()->LoadFromOffset(kLoadWord,
OutputRegister(instruction),
OutputRegister(instruction),
method_offset);
}
}
static void PatchJitRootUse(uint8_t* code,
const uint8_t* roots_data,
VIXLUInt32Literal* literal,
uint64_t index_in_table) {
DCHECK(literal->IsBound());
uint32_t literal_offset = literal->GetLocation();
uintptr_t address =
reinterpret_cast<uintptr_t>(roots_data) + index_in_table * sizeof(GcRoot<mirror::Object>);
uint8_t* data = code + literal_offset;
reinterpret_cast<uint32_t*>(data)[0] = dchecked_integral_cast<uint32_t>(address);
}
void CodeGeneratorARMVIXL::EmitJitRootPatches(uint8_t* code, const uint8_t* roots_data) {
for (const auto& entry : jit_string_patches_) {
const StringReference& string_reference = entry.first;
VIXLUInt32Literal* table_entry_literal = entry.second;
const auto it = jit_string_roots_.find(string_reference);
DCHECK(it != jit_string_roots_.end());
uint64_t index_in_table = it->second;
PatchJitRootUse(code, roots_data, table_entry_literal, index_in_table);
}
for (const auto& entry : jit_class_patches_) {
const TypeReference& type_reference = entry.first;
VIXLUInt32Literal* table_entry_literal = entry.second;
const auto it = jit_class_roots_.find(type_reference);
DCHECK(it != jit_class_roots_.end());
uint64_t index_in_table = it->second;
PatchJitRootUse(code, roots_data, table_entry_literal, index_in_table);
}
}
void CodeGeneratorARMVIXL::EmitMovwMovtPlaceholder(
CodeGeneratorARMVIXL::PcRelativePatchInfo* labels,
vixl32::Register out) {
ExactAssemblyScope aas(GetVIXLAssembler(),
3 * vixl32::kMaxInstructionSizeInBytes,
CodeBufferCheckScope::kMaximumSize);
// TODO(VIXL): Think about using mov instead of movw.
__ bind(&labels->movw_label);
__ movw(out, /* placeholder */ 0u);
__ bind(&labels->movt_label);
__ movt(out, /* placeholder */ 0u);
__ bind(&labels->add_pc_label);
__ add(out, out, pc);
}
#undef __
#undef QUICK_ENTRY_POINT
#undef TODO_VIXL32
} // namespace arm
} // namespace art