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-rw-r--r--compiler/optimizing/code_generator_x86.cc681
-rw-r--r--compiler/optimizing/code_generator_x86.h105
-rw-r--r--compiler/optimizing/intrinsics_x86.cc48
3 files changed, 579 insertions, 255 deletions
diff --git a/compiler/optimizing/code_generator_x86.cc b/compiler/optimizing/code_generator_x86.cc
index 0fb552a59b..469dd49a8e 100644
--- a/compiler/optimizing/code_generator_x86.cc
+++ b/compiler/optimizing/code_generator_x86.cc
@@ -433,6 +433,56 @@ class ArraySetSlowPathX86 : public SlowPathCode {
DISALLOW_COPY_AND_ASSIGN(ArraySetSlowPathX86);
};
+// Slow path marking an object during a read barrier.
+class ReadBarrierMarkSlowPathX86 : public SlowPathCode {
+ public:
+ ReadBarrierMarkSlowPathX86(HInstruction* instruction, Location out, Location obj)
+ : instruction_(instruction), out_(out), obj_(obj) {
+ DCHECK(kEmitCompilerReadBarrier);
+ }
+
+ const char* GetDescription() const OVERRIDE { return "ReadBarrierMarkSlowPathX86"; }
+
+ void EmitNativeCode(CodeGenerator* codegen) OVERRIDE {
+ LocationSummary* locations = instruction_->GetLocations();
+ Register reg_out = out_.AsRegister<Register>();
+ DCHECK(locations->CanCall());
+ DCHECK(!locations->GetLiveRegisters()->ContainsCoreRegister(reg_out));
+ DCHECK(instruction_->IsInstanceFieldGet() ||
+ instruction_->IsStaticFieldGet() ||
+ instruction_->IsArrayGet() ||
+ instruction_->IsLoadClass() ||
+ instruction_->IsLoadString() ||
+ instruction_->IsInstanceOf() ||
+ instruction_->IsCheckCast())
+ << "Unexpected instruction in read barrier marking slow path: "
+ << instruction_->DebugName();
+
+ __ Bind(GetEntryLabel());
+ SaveLiveRegisters(codegen, locations);
+
+ InvokeRuntimeCallingConvention calling_convention;
+ CodeGeneratorX86* x86_codegen = down_cast<CodeGeneratorX86*>(codegen);
+ x86_codegen->Move32(Location::RegisterLocation(calling_convention.GetRegisterAt(0)), obj_);
+ x86_codegen->InvokeRuntime(QUICK_ENTRY_POINT(pReadBarrierMark),
+ instruction_,
+ instruction_->GetDexPc(),
+ this);
+ CheckEntrypointTypes<kQuickReadBarrierMark, mirror::Object*, mirror::Object*>();
+ x86_codegen->Move32(out_, Location::RegisterLocation(EAX));
+
+ RestoreLiveRegisters(codegen, locations);
+ __ jmp(GetExitLabel());
+ }
+
+ private:
+ HInstruction* const instruction_;
+ const Location out_;
+ const Location obj_;
+
+ DISALLOW_COPY_AND_ASSIGN(ReadBarrierMarkSlowPathX86);
+};
+
// Slow path generating a read barrier for a heap reference.
class ReadBarrierForHeapReferenceSlowPathX86 : public SlowPathCode {
public:
@@ -454,7 +504,7 @@ class ReadBarrierForHeapReferenceSlowPathX86 : public SlowPathCode {
// to be instrumented, e.g.:
//
// __ movl(out, Address(out, offset));
- // codegen_->GenerateReadBarrier(instruction, out_loc, out_loc, out_loc, 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.
@@ -470,7 +520,9 @@ class ReadBarrierForHeapReferenceSlowPathX86 : public SlowPathCode {
DCHECK(!locations->GetLiveRegisters()->ContainsCoreRegister(reg_out));
DCHECK(!instruction_->IsInvoke() ||
(instruction_->IsInvokeStaticOrDirect() &&
- instruction_->GetLocations()->Intrinsified()));
+ instruction_->GetLocations()->Intrinsified()))
+ << "Unexpected instruction in read barrier for heap reference slow path: "
+ << instruction_->DebugName();
__ Bind(GetEntryLabel());
SaveLiveRegisters(codegen, locations);
@@ -612,14 +664,18 @@ class ReadBarrierForHeapReferenceSlowPathX86 : public SlowPathCode {
class ReadBarrierForRootSlowPathX86 : public SlowPathCode {
public:
ReadBarrierForRootSlowPathX86(HInstruction* instruction, Location out, Location root)
- : instruction_(instruction), out_(out), root_(root) {}
+ : instruction_(instruction), out_(out), root_(root) {
+ DCHECK(kEmitCompilerReadBarrier);
+ }
void EmitNativeCode(CodeGenerator* codegen) OVERRIDE {
LocationSummary* locations = instruction_->GetLocations();
Register reg_out = out_.AsRegister<Register>();
DCHECK(locations->CanCall());
DCHECK(!locations->GetLiveRegisters()->ContainsCoreRegister(reg_out));
- DCHECK(instruction_->IsLoadClass() || instruction_->IsLoadString());
+ DCHECK(instruction_->IsLoadClass() || instruction_->IsLoadString())
+ << "Unexpected instruction in read barrier for GC root slow path: "
+ << instruction_->DebugName();
__ Bind(GetEntryLabel());
SaveLiveRegisters(codegen, locations);
@@ -1831,7 +1887,7 @@ void LocationsBuilderX86::VisitMemoryBarrier(HMemoryBarrier* memory_barrier) {
}
void InstructionCodeGeneratorX86::VisitMemoryBarrier(HMemoryBarrier* memory_barrier) {
- GenerateMemoryBarrier(memory_barrier->GetBarrierKind());
+ codegen_->GenerateMemoryBarrier(memory_barrier->GetBarrierKind());
}
void LocationsBuilderX86::VisitReturnVoid(HReturnVoid* ret) {
@@ -4092,7 +4148,7 @@ void InstructionCodeGeneratorX86::VisitPhi(HPhi* instruction ATTRIBUTE_UNUSED) {
LOG(FATAL) << "Unreachable";
}
-void InstructionCodeGeneratorX86::GenerateMemoryBarrier(MemBarrierKind kind) {
+void CodeGeneratorX86::GenerateMemoryBarrier(MemBarrierKind kind) {
/*
* According to the JSR-133 Cookbook, for x86 only StoreLoad/AnyAny barriers need memory fence.
* All other barriers (LoadAny, AnyStore, StoreStore) are nops due to the x86 memory model.
@@ -4346,9 +4402,14 @@ void LocationsBuilderX86::HandleFieldGet(HInstruction* instruction, const FieldI
if (field_info.IsVolatile() && (field_info.GetFieldType() == Primitive::kPrimLong)) {
// Long values can be loaded atomically into an XMM using movsd.
- // So we use an XMM register as a temp to achieve atomicity (first load the temp into the XMM
- // and then copy the XMM into the output 32bits at a time).
+ // So we use an XMM register as a temp to achieve atomicity (first
+ // load the temp into the XMM and then copy the XMM into the
+ // output, 32 bits at a time).
locations->AddTemp(Location::RequiresFpuRegister());
+ } else if (object_field_get_with_read_barrier && kUseBakerReadBarrier) {
+ // We need a temporary register for the read barrier marking slow
+ // path in CodeGeneratorX86::GenerateFieldLoadWithBakerReadBarrier.
+ locations->AddTemp(Location::RequiresRegister());
}
}
@@ -4386,9 +4447,32 @@ void InstructionCodeGeneratorX86::HandleFieldGet(HInstruction* instruction,
}
case Primitive::kPrimInt:
- case Primitive::kPrimNot: {
__ movl(out.AsRegister<Register>(), Address(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
+ // CodeGeneratorX86::GenerateFieldLoadWithBakerReadBarrier call.
+ codegen_->GenerateFieldLoadWithBakerReadBarrier(
+ instruction, out, base, offset, temp_loc, /* needs_null_check */ true);
+ if (is_volatile) {
+ codegen_->GenerateMemoryBarrier(MemBarrierKind::kLoadAny);
+ }
+ } else {
+ __ movl(out.AsRegister<Register>(), Address(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, base_loc, offset);
+ }
+ break;
}
case Primitive::kPrimLong: {
@@ -4423,17 +4507,20 @@ void InstructionCodeGeneratorX86::HandleFieldGet(HInstruction* instruction,
UNREACHABLE();
}
- // Longs are handled in the switch.
- if (field_type != Primitive::kPrimLong) {
+ if (field_type == Primitive::kPrimNot || field_type == Primitive::kPrimLong) {
+ // Potential implicit null checks, in the case of reference or
+ // long fields, are handled in the previous switch statement.
+ } else {
codegen_->MaybeRecordImplicitNullCheck(instruction);
}
if (is_volatile) {
- GenerateMemoryBarrier(MemBarrierKind::kLoadAny);
- }
-
- if (field_type == Primitive::kPrimNot) {
- codegen_->MaybeGenerateReadBarrier(instruction, out, out, base_loc, offset);
+ 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);
+ }
}
}
@@ -4498,7 +4585,7 @@ void InstructionCodeGeneratorX86::HandleFieldSet(HInstruction* instruction,
CodeGenerator::StoreNeedsWriteBarrier(field_type, instruction->InputAt(1));
if (is_volatile) {
- GenerateMemoryBarrier(MemBarrierKind::kAnyStore);
+ codegen_->GenerateMemoryBarrier(MemBarrierKind::kAnyStore);
}
bool maybe_record_implicit_null_check_done = false;
@@ -4603,7 +4690,7 @@ void InstructionCodeGeneratorX86::HandleFieldSet(HInstruction* instruction,
}
if (is_volatile) {
- GenerateMemoryBarrier(MemBarrierKind::kAnyAny);
+ codegen_->GenerateMemoryBarrier(MemBarrierKind::kAnyAny);
}
}
@@ -4784,6 +4871,11 @@ void LocationsBuilderX86::VisitArrayGet(HArrayGet* instruction) {
Location::kOutputOverlap :
Location::kNoOutputOverlap);
}
+ // We need a temporary register for the read barrier marking slow
+ // path in CodeGeneratorX86::GenerateArrayLoadWithBakerReadBarrier.
+ if (object_array_get_with_read_barrier && kUseBakerReadBarrier) {
+ locations->AddTemp(Location::RequiresRegister());
+ }
}
void InstructionCodeGeneratorX86::VisitArrayGet(HArrayGet* instruction) {
@@ -4791,12 +4883,13 @@ void InstructionCodeGeneratorX86::VisitArrayGet(HArrayGet* instruction) {
Location obj_loc = locations->InAt(0);
Register obj = obj_loc.AsRegister<Register>();
Location index = locations->InAt(1);
+ Location out_loc = locations->Out();
Primitive::Type type = instruction->GetType();
switch (type) {
case Primitive::kPrimBoolean: {
uint32_t data_offset = mirror::Array::DataOffset(sizeof(uint8_t)).Uint32Value();
- Register out = locations->Out().AsRegister<Register>();
+ Register out = out_loc.AsRegister<Register>();
if (index.IsConstant()) {
__ movzxb(out, Address(obj,
(index.GetConstant()->AsIntConstant()->GetValue() << TIMES_1) + data_offset));
@@ -4808,7 +4901,7 @@ void InstructionCodeGeneratorX86::VisitArrayGet(HArrayGet* instruction) {
case Primitive::kPrimByte: {
uint32_t data_offset = mirror::Array::DataOffset(sizeof(int8_t)).Uint32Value();
- Register out = locations->Out().AsRegister<Register>();
+ Register out = out_loc.AsRegister<Register>();
if (index.IsConstant()) {
__ movsxb(out, Address(obj,
(index.GetConstant()->AsIntConstant()->GetValue() << TIMES_1) + data_offset));
@@ -4820,7 +4913,7 @@ void InstructionCodeGeneratorX86::VisitArrayGet(HArrayGet* instruction) {
case Primitive::kPrimShort: {
uint32_t data_offset = mirror::Array::DataOffset(sizeof(int16_t)).Uint32Value();
- Register out = locations->Out().AsRegister<Register>();
+ Register out = out_loc.AsRegister<Register>();
if (index.IsConstant()) {
__ movsxw(out, Address(obj,
(index.GetConstant()->AsIntConstant()->GetValue() << TIMES_2) + data_offset));
@@ -4832,7 +4925,7 @@ void InstructionCodeGeneratorX86::VisitArrayGet(HArrayGet* instruction) {
case Primitive::kPrimChar: {
uint32_t data_offset = mirror::Array::DataOffset(sizeof(uint16_t)).Uint32Value();
- Register out = locations->Out().AsRegister<Register>();
+ Register out = out_loc.AsRegister<Register>();
if (index.IsConstant()) {
__ movzxw(out, Address(obj,
(index.GetConstant()->AsIntConstant()->GetValue() << TIMES_2) + data_offset));
@@ -4842,13 +4935,9 @@ void InstructionCodeGeneratorX86::VisitArrayGet(HArrayGet* instruction) {
break;
}
- case Primitive::kPrimInt:
- case Primitive::kPrimNot: {
- static_assert(
- sizeof(mirror::HeapReference<mirror::Object>) == sizeof(int32_t),
- "art::mirror::HeapReference<art::mirror::Object> and int32_t have different sizes.");
+ case Primitive::kPrimInt: {
uint32_t data_offset = mirror::Array::DataOffset(sizeof(int32_t)).Uint32Value();
- Register out = locations->Out().AsRegister<Register>();
+ Register out = out_loc.AsRegister<Register>();
if (index.IsConstant()) {
__ movl(out, Address(obj,
(index.GetConstant()->AsIntConstant()->GetValue() << TIMES_4) + data_offset));
@@ -4858,20 +4947,56 @@ void InstructionCodeGeneratorX86::VisitArrayGet(HArrayGet* instruction) {
break;
}
+ case Primitive::kPrimNot: {
+ static_assert(
+ sizeof(mirror::HeapReference<mirror::Object>) == sizeof(int32_t),
+ "art::mirror::HeapReference<art::mirror::Object> and int32_t have different sizes.");
+ uint32_t data_offset = mirror::Array::DataOffset(sizeof(int32_t)).Uint32Value();
+ // /* 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
+ // CodeGeneratorX86::GenerateArrayLoadWithBakerReadBarrier call.
+ codegen_->GenerateArrayLoadWithBakerReadBarrier(
+ instruction, out_loc, obj, data_offset, index, temp, /* needs_null_check */ true);
+ } else {
+ Register out = out_loc.AsRegister<Register>();
+ if (index.IsConstant()) {
+ uint32_t offset =
+ (index.GetConstant()->AsIntConstant()->GetValue() << TIMES_4) + data_offset;
+ __ movl(out, Address(obj, offset));
+ 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 {
+ __ movl(out, Address(obj, index.AsRegister<Register>(), TIMES_4, data_offset));
+ 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: {
uint32_t data_offset = mirror::Array::DataOffset(sizeof(int64_t)).Uint32Value();
- Location out = locations->Out();
- DCHECK_NE(obj, out.AsRegisterPairLow<Register>());
+ DCHECK_NE(obj, out_loc.AsRegisterPairLow<Register>());
if (index.IsConstant()) {
size_t offset = (index.GetConstant()->AsIntConstant()->GetValue() << TIMES_8) + data_offset;
- __ movl(out.AsRegisterPairLow<Register>(), Address(obj, offset));
+ __ movl(out_loc.AsRegisterPairLow<Register>(), Address(obj, offset));
codegen_->MaybeRecordImplicitNullCheck(instruction);
- __ movl(out.AsRegisterPairHigh<Register>(), Address(obj, offset + kX86WordSize));
+ __ movl(out_loc.AsRegisterPairHigh<Register>(), Address(obj, offset + kX86WordSize));
} else {
- __ movl(out.AsRegisterPairLow<Register>(),
+ __ movl(out_loc.AsRegisterPairLow<Register>(),
Address(obj, index.AsRegister<Register>(), TIMES_8, data_offset));
codegen_->MaybeRecordImplicitNullCheck(instruction);
- __ movl(out.AsRegisterPairHigh<Register>(),
+ __ movl(out_loc.AsRegisterPairHigh<Register>(),
Address(obj, index.AsRegister<Register>(), TIMES_8, data_offset + kX86WordSize));
}
break;
@@ -4879,7 +5004,7 @@ void InstructionCodeGeneratorX86::VisitArrayGet(HArrayGet* instruction) {
case Primitive::kPrimFloat: {
uint32_t data_offset = mirror::Array::DataOffset(sizeof(float)).Uint32Value();
- XmmRegister out = locations->Out().AsFpuRegister<XmmRegister>();
+ XmmRegister out = out_loc.AsFpuRegister<XmmRegister>();
if (index.IsConstant()) {
__ movss(out, Address(obj,
(index.GetConstant()->AsIntConstant()->GetValue() << TIMES_4) + data_offset));
@@ -4891,7 +5016,7 @@ void InstructionCodeGeneratorX86::VisitArrayGet(HArrayGet* instruction) {
case Primitive::kPrimDouble: {
uint32_t data_offset = mirror::Array::DataOffset(sizeof(double)).Uint32Value();
- XmmRegister out = locations->Out().AsFpuRegister<XmmRegister>();
+ XmmRegister out = out_loc.AsFpuRegister<XmmRegister>();
if (index.IsConstant()) {
__ movsd(out, Address(obj,
(index.GetConstant()->AsIntConstant()->GetValue() << TIMES_8) + data_offset));
@@ -4906,23 +5031,12 @@ void InstructionCodeGeneratorX86::VisitArrayGet(HArrayGet* instruction) {
UNREACHABLE();
}
- if (type != Primitive::kPrimLong) {
+ if (type == Primitive::kPrimNot || type == Primitive::kPrimLong) {
+ // Potential implicit null checks, in the case of reference or
+ // long arrays, are handled in the previous switch statement.
+ } else {
codegen_->MaybeRecordImplicitNullCheck(instruction);
}
-
- if (type == Primitive::kPrimNot) {
- static_assert(
- sizeof(mirror::HeapReference<mirror::Object>) == sizeof(int32_t),
- "art::mirror::HeapReference<art::mirror::Object> and int32_t have different sizes.");
- uint32_t data_offset = mirror::Array::DataOffset(sizeof(int32_t)).Uint32Value();
- Location out = locations->Out();
- if (index.IsConstant()) {
- uint32_t offset = (index.GetConstant()->AsIntConstant()->GetValue() << TIMES_4) + data_offset;
- codegen_->MaybeGenerateReadBarrier(instruction, out, out, obj_loc, offset);
- } else {
- codegen_->MaybeGenerateReadBarrier(instruction, out, out, obj_loc, data_offset, index);
- }
- }
}
void LocationsBuilderX86::VisitArraySet(HArraySet* instruction) {
@@ -5054,12 +5168,12 @@ void InstructionCodeGeneratorX86::VisitArraySet(HArraySet* instruction) {
// __ movl(temp2, temp);
// // /* HeapReference<Class> */ temp = temp->component_type_
// __ movl(temp, Address(temp, component_offset));
- // codegen_->GenerateReadBarrier(
+ // codegen_->GenerateReadBarrierSlow(
// instruction, temp_loc, temp_loc, temp2_loc, component_offset);
//
// // /* HeapReference<Class> */ temp2 = register_value->klass_
// __ movl(temp2, Address(register_value, class_offset));
- // codegen_->GenerateReadBarrier(
+ // codegen_->GenerateReadBarrierSlow(
// instruction, temp2_loc, temp2_loc, value, class_offset, temp_loc);
//
// __ cmpl(temp, temp2);
@@ -5340,8 +5454,8 @@ void InstructionCodeGeneratorX86::GenerateSuspendCheck(HSuspendCheck* instructio
DCHECK_EQ(slow_path->GetSuccessor(), successor);
}
- __ fs()->cmpw(Address::Absolute(
- Thread::ThreadFlagsOffset<kX86WordSize>().Int32Value()), Immediate(0));
+ __ fs()->cmpw(Address::Absolute(Thread::ThreadFlagsOffset<kX86WordSize>().Int32Value()),
+ Immediate(0));
if (successor == nullptr) {
__ j(kNotEqual, slow_path->GetEntryLabel());
__ Bind(slow_path->GetReturnLabel());
@@ -5622,32 +5736,16 @@ void InstructionCodeGeneratorX86::VisitLoadClass(HLoadClass* cls) {
if (cls->IsReferrersClass()) {
DCHECK(!cls->CanCallRuntime());
DCHECK(!cls->MustGenerateClinitCheck());
- uint32_t declaring_class_offset = ArtMethod::DeclaringClassOffset().Int32Value();
- if (kEmitCompilerReadBarrier) {
- // /* GcRoot<mirror::Class>* */ out = &(current_method->declaring_class_)
- __ leal(out, Address(current_method, declaring_class_offset));
- // /* mirror::Class* */ out = out->Read()
- codegen_->GenerateReadBarrierForRoot(cls, out_loc, out_loc);
- } else {
- // /* GcRoot<mirror::Class> */ out = current_method->declaring_class_
- __ movl(out, Address(current_method, declaring_class_offset));
- }
+ // /* GcRoot<mirror::Class> */ out = current_method->declaring_class_
+ GenerateGcRootFieldLoad(
+ cls, out_loc, current_method, ArtMethod::DeclaringClassOffset().Int32Value());
} else {
// /* GcRoot<mirror::Class>[] */ out =
// current_method.ptr_sized_fields_->dex_cache_resolved_types_
__ movl(out, Address(current_method,
ArtMethod::DexCacheResolvedTypesOffset(kX86PointerSize).Int32Value()));
-
- size_t cache_offset = CodeGenerator::GetCacheOffset(cls->GetTypeIndex());
- if (kEmitCompilerReadBarrier) {
- // /* GcRoot<mirror::Class>* */ out = &out[type_index]
- __ leal(out, Address(out, cache_offset));
- // /* mirror::Class* */ out = out->Read()
- codegen_->GenerateReadBarrierForRoot(cls, out_loc, out_loc);
- } else {
- // /* GcRoot<mirror::Class> */ out = out[type_index]
- __ movl(out, Address(out, cache_offset));
- }
+ // /* GcRoot<mirror::Class> */ out = out[type_index]
+ GenerateGcRootFieldLoad(cls, out_loc, out, CodeGenerator::GetCacheOffset(cls->GetTypeIndex()));
if (!cls->IsInDexCache() || cls->MustGenerateClinitCheck()) {
DCHECK(cls->CanCallRuntime());
@@ -5711,30 +5809,14 @@ void InstructionCodeGeneratorX86::VisitLoadString(HLoadString* load) {
Register out = out_loc.AsRegister<Register>();
Register current_method = locations->InAt(0).AsRegister<Register>();
- uint32_t declaring_class_offset = ArtMethod::DeclaringClassOffset().Int32Value();
- if (kEmitCompilerReadBarrier) {
- // /* GcRoot<mirror::Class>* */ out = &(current_method->declaring_class_)
- __ leal(out, Address(current_method, declaring_class_offset));
- // /* mirror::Class* */ out = out->Read()
- codegen_->GenerateReadBarrierForRoot(load, out_loc, out_loc);
- } else {
- // /* GcRoot<mirror::Class> */ out = current_method->declaring_class_
- __ movl(out, Address(current_method, declaring_class_offset));
- }
-
+ // /* GcRoot<mirror::Class> */ out = current_method->declaring_class_
+ GenerateGcRootFieldLoad(
+ load, out_loc, current_method, ArtMethod::DeclaringClassOffset().Int32Value());
// /* GcRoot<mirror::String>[] */ out = out->dex_cache_strings_
__ movl(out, Address(out, mirror::Class::DexCacheStringsOffset().Int32Value()));
-
- size_t cache_offset = CodeGenerator::GetCacheOffset(load->GetStringIndex());
- if (kEmitCompilerReadBarrier) {
- // /* GcRoot<mirror::String>* */ out = &out[string_index]
- __ leal(out, Address(out, cache_offset));
- // /* mirror::String* */ out = out->Read()
- codegen_->GenerateReadBarrierForRoot(load, out_loc, out_loc);
- } else {
- // /* GcRoot<mirror::String> */ out = out[string_index]
- __ movl(out, Address(out, cache_offset));
- }
+ // /* GcRoot<mirror::String> */ out = out[string_index]
+ GenerateGcRootFieldLoad(
+ load, out_loc, out, CodeGenerator::GetCacheOffset(load->GetStringIndex()));
if (!load->IsInDexCache()) {
SlowPathCode* slow_path = new (GetGraph()->GetArena()) LoadStringSlowPathX86(load);
@@ -5782,6 +5864,14 @@ void InstructionCodeGeneratorX86::VisitThrow(HThrow* instruction) {
CheckEntrypointTypes<kQuickDeliverException, void, mirror::Object*>();
}
+static bool TypeCheckNeedsATemporary(TypeCheckKind type_check_kind) {
+ return kEmitCompilerReadBarrier &&
+ (kUseBakerReadBarrier ||
+ type_check_kind == TypeCheckKind::kAbstractClassCheck ||
+ type_check_kind == TypeCheckKind::kClassHierarchyCheck ||
+ type_check_kind == TypeCheckKind::kArrayObjectCheck);
+}
+
void LocationsBuilderX86::VisitInstanceOf(HInstanceOf* instruction) {
LocationSummary::CallKind call_kind = LocationSummary::kNoCall;
TypeCheckKind type_check_kind = instruction->GetTypeCheckKind();
@@ -5807,21 +5897,22 @@ void LocationsBuilderX86::VisitInstanceOf(HInstanceOf* instruction) {
locations->SetOut(Location::RequiresRegister());
// When read barriers are enabled, we need a temporary register for
// some cases.
- if (kEmitCompilerReadBarrier &&
- (type_check_kind == TypeCheckKind::kAbstractClassCheck ||
- type_check_kind == TypeCheckKind::kClassHierarchyCheck ||
- type_check_kind == TypeCheckKind::kArrayObjectCheck)) {
+ if (TypeCheckNeedsATemporary(type_check_kind)) {
locations->AddTemp(Location::RequiresRegister());
}
}
void InstructionCodeGeneratorX86::VisitInstanceOf(HInstanceOf* instruction) {
+ TypeCheckKind type_check_kind = instruction->GetTypeCheckKind();
LocationSummary* locations = instruction->GetLocations();
Location obj_loc = locations->InAt(0);
Register obj = obj_loc.AsRegister<Register>();
Location cls = locations->InAt(1);
Location out_loc = locations->Out();
Register out = out_loc.AsRegister<Register>();
+ Location temp_loc = TypeCheckNeedsATemporary(type_check_kind) ?
+ 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();
@@ -5837,10 +5928,9 @@ void InstructionCodeGeneratorX86::VisitInstanceOf(HInstanceOf* instruction) {
}
// /* HeapReference<Class> */ out = obj->klass_
- __ movl(out, Address(obj, class_offset));
- codegen_->MaybeGenerateReadBarrier(instruction, out_loc, out_loc, obj_loc, class_offset);
+ GenerateReferenceLoadTwoRegisters(instruction, out_loc, obj_loc, class_offset, temp_loc);
- switch (instruction->GetTypeCheckKind()) {
+ switch (type_check_kind) {
case TypeCheckKind::kExactCheck: {
if (cls.IsRegister()) {
__ cmpl(out, cls.AsRegister<Register>());
@@ -5861,17 +5951,8 @@ void InstructionCodeGeneratorX86::VisitInstanceOf(HInstanceOf* instruction) {
// object to avoid doing a comparison we know will fail.
NearLabel loop;
__ Bind(&loop);
- Location temp_loc = kEmitCompilerReadBarrier ? locations->GetTemp(0) : Location::NoLocation();
- if (kEmitCompilerReadBarrier) {
- // Save the value of `out` into `temp` before overwriting it
- // in the following move operation, as we will need it for the
- // read barrier below.
- Register temp = temp_loc.AsRegister<Register>();
- __ movl(temp, out);
- }
// /* HeapReference<Class> */ out = out->super_class_
- __ movl(out, Address(out, super_offset));
- codegen_->MaybeGenerateReadBarrier(instruction, out_loc, out_loc, temp_loc, super_offset);
+ GenerateReferenceLoadOneRegister(instruction, out_loc, super_offset, temp_loc);
__ testl(out, out);
// If `out` is null, we use it for the result, and jump to `done`.
__ j(kEqual, &done);
@@ -5900,17 +5981,8 @@ void InstructionCodeGeneratorX86::VisitInstanceOf(HInstanceOf* instruction) {
__ cmpl(out, Address(ESP, cls.GetStackIndex()));
}
__ j(kEqual, &success);
- Location temp_loc = kEmitCompilerReadBarrier ? locations->GetTemp(0) : Location::NoLocation();
- if (kEmitCompilerReadBarrier) {
- // Save the value of `out` into `temp` before overwriting it
- // in the following move operation, as we will need it for the
- // read barrier below.
- Register temp = temp_loc.AsRegister<Register>();
- __ movl(temp, out);
- }
// /* HeapReference<Class> */ out = out->super_class_
- __ movl(out, Address(out, super_offset));
- codegen_->MaybeGenerateReadBarrier(instruction, out_loc, out_loc, temp_loc, super_offset);
+ GenerateReferenceLoadOneRegister(instruction, out_loc, super_offset, temp_loc);
__ testl(out, out);
__ j(kNotEqual, &loop);
// If `out` is null, we use it for the result, and jump to `done`.
@@ -5934,17 +6006,8 @@ void InstructionCodeGeneratorX86::VisitInstanceOf(HInstanceOf* instruction) {
}
__ j(kEqual, &exact_check);
// Otherwise, we need to check that the object's class is a non-primitive array.
- Location temp_loc = kEmitCompilerReadBarrier ? locations->GetTemp(0) : Location::NoLocation();
- if (kEmitCompilerReadBarrier) {
- // Save the value of `out` into `temp` before overwriting it
- // in the following move operation, as we will need it for the
- // read barrier below.
- Register temp = temp_loc.AsRegister<Register>();
- __ movl(temp, out);
- }
// /* HeapReference<Class> */ out = out->component_type_
- __ movl(out, Address(out, component_offset));
- codegen_->MaybeGenerateReadBarrier(instruction, out_loc, out_loc, temp_loc, component_offset);
+ GenerateReferenceLoadOneRegister(instruction, out_loc, component_offset, temp_loc);
__ testl(out, out);
// If `out` is null, we use it for the result, and jump to `done`.
__ j(kEqual, &done);
@@ -5988,6 +6051,13 @@ void InstructionCodeGeneratorX86::VisitInstanceOf(HInstanceOf* instruction) {
// 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()) TypeCheckSlowPathX86(instruction,
/* is_fatal */ false);
@@ -6040,27 +6110,27 @@ void LocationsBuilderX86::VisitCheckCast(HCheckCast* instruction) {
locations->AddTemp(Location::RequiresRegister());
// When read barriers are enabled, we need an additional temporary
// register for some cases.
- if (kEmitCompilerReadBarrier &&
- (type_check_kind == TypeCheckKind::kAbstractClassCheck ||
- type_check_kind == TypeCheckKind::kClassHierarchyCheck ||
- type_check_kind == TypeCheckKind::kArrayObjectCheck)) {
+ if (TypeCheckNeedsATemporary(type_check_kind)) {
locations->AddTemp(Location::RequiresRegister());
}
}
void InstructionCodeGeneratorX86::VisitCheckCast(HCheckCast* instruction) {
+ TypeCheckKind type_check_kind = instruction->GetTypeCheckKind();
LocationSummary* locations = instruction->GetLocations();
Location obj_loc = locations->InAt(0);
Register obj = obj_loc.AsRegister<Register>();
Location cls = locations->InAt(1);
Location temp_loc = locations->GetTemp(0);
Register temp = temp_loc.AsRegister<Register>();
+ Location temp2_loc = TypeCheckNeedsATemporary(type_check_kind) ?
+ locations->GetTemp(1) :
+ 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();
- TypeCheckKind type_check_kind = instruction->GetTypeCheckKind();
bool is_type_check_slow_path_fatal =
(type_check_kind == TypeCheckKind::kExactCheck ||
type_check_kind == TypeCheckKind::kAbstractClassCheck ||
@@ -6080,8 +6150,7 @@ void InstructionCodeGeneratorX86::VisitCheckCast(HCheckCast* instruction) {
}
// /* HeapReference<Class> */ temp = obj->klass_
- __ movl(temp, Address(obj, class_offset));
- codegen_->MaybeGenerateReadBarrier(instruction, temp_loc, temp_loc, obj_loc, class_offset);
+ GenerateReferenceLoadTwoRegisters(instruction, temp_loc, obj_loc, class_offset, temp2_loc);
switch (type_check_kind) {
case TypeCheckKind::kExactCheck:
@@ -6103,18 +6172,8 @@ void InstructionCodeGeneratorX86::VisitCheckCast(HCheckCast* instruction) {
// object to avoid doing a comparison we know will fail.
NearLabel loop, compare_classes;
__ Bind(&loop);
- Location temp2_loc =
- kEmitCompilerReadBarrier ? locations->GetTemp(1) : Location::NoLocation();
- if (kEmitCompilerReadBarrier) {
- // Save the value of `temp` into `temp2` before overwriting it
- // in the following move operation, as we will need it for the
- // read barrier below.
- Register temp2 = temp2_loc.AsRegister<Register>();
- __ movl(temp2, temp);
- }
// /* HeapReference<Class> */ temp = temp->super_class_
- __ movl(temp, Address(temp, super_offset));
- codegen_->MaybeGenerateReadBarrier(instruction, temp_loc, temp_loc, temp2_loc, super_offset);
+ GenerateReferenceLoadOneRegister(instruction, temp_loc, super_offset, temp2_loc);
// If the class reference currently in `temp` is not null, jump
// to the `compare_classes` label to compare it with the checked
@@ -6127,8 +6186,7 @@ void InstructionCodeGeneratorX86::VisitCheckCast(HCheckCast* instruction) {
// going into the slow path, as it has been overwritten in the
// meantime.
// /* HeapReference<Class> */ temp = obj->klass_
- __ movl(temp, Address(obj, class_offset));
- codegen_->MaybeGenerateReadBarrier(instruction, temp_loc, temp_loc, obj_loc, class_offset);
+ GenerateReferenceLoadTwoRegisters(instruction, temp_loc, obj_loc, class_offset, temp2_loc);
__ jmp(type_check_slow_path->GetEntryLabel());
__ Bind(&compare_classes);
@@ -6154,18 +6212,8 @@ void InstructionCodeGeneratorX86::VisitCheckCast(HCheckCast* instruction) {
}
__ j(kEqual, &done);
- Location temp2_loc =
- kEmitCompilerReadBarrier ? locations->GetTemp(1) : Location::NoLocation();
- if (kEmitCompilerReadBarrier) {
- // Save the value of `temp` into `temp2` before overwriting it
- // in the following move operation, as we will need it for the
- // read barrier below.
- Register temp2 = temp2_loc.AsRegister<Register>();
- __ movl(temp2, temp);
- }
// /* HeapReference<Class> */ temp = temp->super_class_
- __ movl(temp, Address(temp, super_offset));
- codegen_->MaybeGenerateReadBarrier(instruction, temp_loc, temp_loc, temp2_loc, super_offset);
+ GenerateReferenceLoadOneRegister(instruction, temp_loc, super_offset, temp2_loc);
// If the class reference currently in `temp` is not null, jump
// back at the beginning of the loop.
@@ -6177,8 +6225,7 @@ void InstructionCodeGeneratorX86::VisitCheckCast(HCheckCast* instruction) {
// going into the slow path, as it has been overwritten in the
// meantime.
// /* HeapReference<Class> */ temp = obj->klass_
- __ movl(temp, Address(obj, class_offset));
- codegen_->MaybeGenerateReadBarrier(instruction, temp_loc, temp_loc, obj_loc, class_offset);
+ GenerateReferenceLoadTwoRegisters(instruction, temp_loc, obj_loc, class_offset, temp2_loc);
__ jmp(type_check_slow_path->GetEntryLabel());
break;
}
@@ -6195,19 +6242,8 @@ void InstructionCodeGeneratorX86::VisitCheckCast(HCheckCast* instruction) {
__ j(kEqual, &done);
// Otherwise, we need to check that the object's class is a non-primitive array.
- Location temp2_loc =
- kEmitCompilerReadBarrier ? locations->GetTemp(1) : Location::NoLocation();
- if (kEmitCompilerReadBarrier) {
- // Save the value of `temp` into `temp2` before overwriting it
- // in the following move operation, as we will need it for the
- // read barrier below.
- Register temp2 = temp2_loc.AsRegister<Register>();
- __ movl(temp2, temp);
- }
// /* HeapReference<Class> */ temp = temp->component_type_
- __ movl(temp, Address(temp, component_offset));
- codegen_->MaybeGenerateReadBarrier(
- instruction, temp_loc, temp_loc, temp2_loc, component_offset);
+ GenerateReferenceLoadOneRegister(instruction, temp_loc, component_offset, temp2_loc);
// If the component type is not null (i.e. the object is indeed
// an array), jump to label `check_non_primitive_component_type`
@@ -6221,8 +6257,7 @@ void InstructionCodeGeneratorX86::VisitCheckCast(HCheckCast* instruction) {
// going into the slow path, as it has been overwritten in the
// meantime.
// /* HeapReference<Class> */ temp = obj->klass_
- __ movl(temp, Address(obj, class_offset));
- codegen_->MaybeGenerateReadBarrier(instruction, temp_loc, temp_loc, obj_loc, class_offset);
+ GenerateReferenceLoadTwoRegisters(instruction, temp_loc, obj_loc, class_offset, temp2_loc);
__ jmp(type_check_slow_path->GetEntryLabel());
__ Bind(&check_non_primitive_component_type);
@@ -6230,8 +6265,7 @@ void InstructionCodeGeneratorX86::VisitCheckCast(HCheckCast* instruction) {
__ j(kEqual, &done);
// Same comment as above regarding `temp` and the slow path.
// /* HeapReference<Class> */ temp = obj->klass_
- __ movl(temp, Address(obj, class_offset));
- codegen_->MaybeGenerateReadBarrier(instruction, temp_loc, temp_loc, obj_loc, class_offset);
+ GenerateReferenceLoadTwoRegisters(instruction, temp_loc, obj_loc, class_offset, temp2_loc);
__ jmp(type_check_slow_path->GetEntryLabel());
break;
}
@@ -6248,6 +6282,13 @@ void InstructionCodeGeneratorX86::VisitCheckCast(HCheckCast* instruction) {
// 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.
__ jmp(type_check_slow_path->GetEntryLabel());
break;
}
@@ -6409,14 +6450,226 @@ void InstructionCodeGeneratorX86::HandleBitwiseOperation(HBinaryOperation* instr
}
}
-void CodeGeneratorX86::GenerateReadBarrier(HInstruction* instruction,
- Location out,
- Location ref,
- Location obj,
- uint32_t offset,
- Location index) {
+void InstructionCodeGeneratorX86::GenerateReferenceLoadOneRegister(HInstruction* instruction,
+ Location out,
+ uint32_t offset,
+ Location temp) {
+ Register out_reg = out.AsRegister<Register>();
+ if (kEmitCompilerReadBarrier) {
+ if (kUseBakerReadBarrier) {
+ // Load with fast path based Baker's read barrier.
+ // /* HeapReference<Object> */ out = *(out + offset)
+ codegen_->GenerateFieldLoadWithBakerReadBarrier(
+ instruction, out, out_reg, offset, temp, /* needs_null_check */ false);
+ } else {
+ // Load with slow path based read barrier.
+ // Save the value of `out` into `temp` before overwriting it
+ // in the following move operation, as we will need it for the
+ // read barrier below.
+ __ movl(temp.AsRegister<Register>(), out_reg);
+ // /* HeapReference<Object> */ out = *(out + offset)
+ __ movl(out_reg, Address(out_reg, offset));
+ codegen_->GenerateReadBarrierSlow(instruction, out, out, temp, offset);
+ }
+ } else {
+ // Plain load with no read barrier.
+ // /* HeapReference<Object> */ out = *(out + offset)
+ __ movl(out_reg, Address(out_reg, offset));
+ __ MaybeUnpoisonHeapReference(out_reg);
+ }
+}
+
+void InstructionCodeGeneratorX86::GenerateReferenceLoadTwoRegisters(HInstruction* instruction,
+ Location out,
+ Location obj,
+ uint32_t offset,
+ Location temp) {
+ Register out_reg = out.AsRegister<Register>();
+ Register obj_reg = obj.AsRegister<Register>();
+ if (kEmitCompilerReadBarrier) {
+ if (kUseBakerReadBarrier) {
+ // Load with fast path based Baker's read barrier.
+ // /* HeapReference<Object> */ out = *(obj + offset)
+ codegen_->GenerateFieldLoadWithBakerReadBarrier(
+ instruction, out, obj_reg, offset, temp, /* needs_null_check */ false);
+ } else {
+ // Load with slow path based read barrier.
+ // /* HeapReference<Object> */ out = *(obj + offset)
+ __ movl(out_reg, Address(obj_reg, offset));
+ codegen_->GenerateReadBarrierSlow(instruction, out, out, obj, offset);
+ }
+ } else {
+ // Plain load with no read barrier.
+ // /* HeapReference<Object> */ out = *(obj + offset)
+ __ movl(out_reg, Address(obj_reg, offset));
+ __ MaybeUnpoisonHeapReference(out_reg);
+ }
+}
+
+void InstructionCodeGeneratorX86::GenerateGcRootFieldLoad(HInstruction* instruction,
+ Location root,
+ Register obj,
+ uint32_t offset) {
+ Register root_reg = root.AsRegister<Register>();
+ if (kEmitCompilerReadBarrier) {
+ if (kUseBakerReadBarrier) {
+ // Fast path implementation of art::ReadBarrier::BarrierForRoot when
+ // Baker's read barrier are used:
+ //
+ // root = obj.field;
+ // if (Thread::Current()->GetIsGcMarking()) {
+ // root = ReadBarrier::Mark(root)
+ // }
+
+ // /* GcRoot<mirror::Object> */ root = *(obj + offset)
+ __ movl(root_reg, Address(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.");
+
+ // Slow path used to mark the GC root `root`.
+ SlowPathCode* slow_path =
+ new (GetGraph()->GetArena()) ReadBarrierMarkSlowPathX86(instruction, root, root);
+ codegen_->AddSlowPath(slow_path);
+
+ __ fs()->cmpl(Address::Absolute(Thread::IsGcMarkingOffset<kX86WordSize>().Int32Value()),
+ Immediate(0));
+ __ j(kNotEqual, 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
+ __ leal(root_reg, Address(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)
+ __ movl(root_reg, Address(obj, offset));
+ }
+}
+
+void CodeGeneratorX86::GenerateFieldLoadWithBakerReadBarrier(HInstruction* instruction,
+ Location ref,
+ Register obj,
+ uint32_t offset,
+ Location temp,
+ bool needs_null_check) {
+ DCHECK(kEmitCompilerReadBarrier);
+ DCHECK(kUseBakerReadBarrier);
+
+ // /* HeapReference<Object> */ ref = *(obj + offset)
+ Address src(obj, offset);
+ GenerateReferenceLoadWithBakerReadBarrier(instruction, ref, obj, src, temp, needs_null_check);
+}
+
+void CodeGeneratorX86::GenerateArrayLoadWithBakerReadBarrier(HInstruction* instruction,
+ Location ref,
+ Register obj,
+ uint32_t data_offset,
+ Location index,
+ Location temp,
+ bool needs_null_check) {
+ DCHECK(kEmitCompilerReadBarrier);
+ DCHECK(kUseBakerReadBarrier);
+
+ // /* HeapReference<Object> */ ref =
+ // *(obj + data_offset + index * sizeof(HeapReference<Object>))
+ Address src = index.IsConstant() ?
+ Address(obj, (index.GetConstant()->AsIntConstant()->GetValue() << TIMES_4) + data_offset) :
+ Address(obj, index.AsRegister<Register>(), TIMES_4, data_offset);
+ GenerateReferenceLoadWithBakerReadBarrier(instruction, ref, obj, src, temp, needs_null_check);
+}
+
+void CodeGeneratorX86::GenerateReferenceLoadWithBakerReadBarrier(HInstruction* instruction,
+ Location ref,
+ Register obj,
+ const Address& src,
+ Location temp,
+ bool needs_null_check) {
+ DCHECK(kEmitCompilerReadBarrier);
+ DCHECK(kUseBakerReadBarrier);
+
+ // In slow path based read barriers, 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 fast path/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<Object> ref = *src; // Original reference load.
+ // bool is_gray = (rb_state == ReadBarrier::gray_ptr_);
+ // if (is_gray) {
+ // ref = ReadBarrier::Mark(ref); // Performed by runtime entrypoint slow path.
+ // }
+ //
+ // Note: the original implementation in ReadBarrier::Barrier is
+ // slightly more complex as:
+ // - it implements the load-load fence using a data dependency on
+ // the high-bits of rb_state, which are expected to be all zeroes;
+ // - it performs additional checks that we do not do here for
+ // performance reasons.
+
+ Register ref_reg = ref.AsRegister<Register>();
+ Register temp_reg = temp.AsRegister<Register>();
+ uint32_t monitor_offset = mirror::Object::MonitorOffset().Int32Value();
+
+ // /* int32_t */ monitor = obj->monitor_
+ __ movl(temp_reg, Address(obj, monitor_offset));
+ if (needs_null_check) {
+ MaybeRecordImplicitNullCheck(instruction);
+ }
+ // /* LockWord */ lock_word = LockWord(monitor)
+ static_assert(sizeof(LockWord) == sizeof(int32_t),
+ "art::LockWord and int32_t have different sizes.");
+ // /* uint32_t */ rb_state = lock_word.ReadBarrierState()
+ __ shrl(temp_reg, Immediate(LockWord::kReadBarrierStateShift));
+ __ andl(temp_reg, Immediate(LockWord::kReadBarrierStateMask));
+ static_assert(
+ LockWord::kReadBarrierStateMask == ReadBarrier::rb_ptr_mask_,
+ "art::LockWord::kReadBarrierStateMask is not equal to art::ReadBarrier::rb_ptr_mask_.");
+
+ // Load fence to prevent load-load reordering.
+ // Note that this is a no-op, thanks to the x86 memory model.
+ GenerateMemoryBarrier(MemBarrierKind::kLoadAny);
+
+ // The actual reference load.
+ // /* HeapReference<Object> */ ref = *src
+ __ movl(ref_reg, src);
+
+ // Object* ref = ref_addr->AsMirrorPtr()
+ __ MaybeUnpoisonHeapReference(ref_reg);
+
+ // Slow path used to mark the object `ref` when it is gray.
+ SlowPathCode* slow_path =
+ new (GetGraph()->GetArena()) ReadBarrierMarkSlowPathX86(instruction, ref, ref);
+ AddSlowPath(slow_path);
+
+ // if (rb_state == ReadBarrier::gray_ptr_)
+ // ref = ReadBarrier::Mark(ref);
+ __ cmpl(temp_reg, Immediate(ReadBarrier::gray_ptr_));
+ __ j(kEqual, slow_path->GetEntryLabel());
+ __ Bind(slow_path->GetExitLabel());
+}
+
+void CodeGeneratorX86::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.
@@ -6430,57 +6683,41 @@ void CodeGeneratorX86::GenerateReadBarrier(HInstruction* instruction,
ReadBarrierForHeapReferenceSlowPathX86(instruction, out, ref, obj, offset, index);
AddSlowPath(slow_path);
- // TODO: When read barrier has a fast path, add it here.
- /* Currently the read barrier call is inserted after the original load.
- * However, if we have a fast path, we need to perform the load of obj.LockWord *before* the
- * original load. This load-load ordering is required by the read barrier.
- * The fast path/slow path (for Baker's algorithm) should look like:
- *
- * bool isGray = obj.LockWord & kReadBarrierMask;
- * lfence; // load fence or artificial data dependence to prevent load-load reordering
- * ref = obj.field; // this is the original load
- * if (isGray) {
- * ref = Mark(ref); // ideally the slow path just does Mark(ref)
- * }
- */
-
__ jmp(slow_path->GetEntryLabel());
__ Bind(slow_path->GetExitLabel());
}
-void CodeGeneratorX86::MaybeGenerateReadBarrier(HInstruction* instruction,
- Location out,
- Location ref,
- Location obj,
- uint32_t offset,
- Location index) {
+void CodeGeneratorX86::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
+ // (CodeGeneratorX86::GenerateReferenceLoadWithBakerReadBarrier).
+ DCHECK(!kUseBakerReadBarrier);
// If heap poisoning is enabled, unpoisoning will be taken care of
// by the runtime within the slow path.
- GenerateReadBarrier(instruction, out, ref, obj, offset, index);
+ GenerateReadBarrierSlow(instruction, out, ref, obj, offset, index);
} else if (kPoisonHeapReferences) {
__ UnpoisonHeapReference(out.AsRegister<Register>());
}
}
-void CodeGeneratorX86::GenerateReadBarrierForRoot(HInstruction* instruction,
- Location out,
- Location root) {
+void CodeGeneratorX86::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.
SlowPathCode* slow_path =
new (GetGraph()->GetArena()) ReadBarrierForRootSlowPathX86(instruction, out, root);
AddSlowPath(slow_path);
- // TODO: Implement a fast path for ReadBarrierForRoot, performing
- // the following operation (for Baker's algorithm):
- //
- // if (thread.tls32_.is_gc_marking) {
- // root = Mark(root);
- // }
-
__ jmp(slow_path->GetEntryLabel());
__ Bind(slow_path->GetExitLabel());
}
@@ -6839,7 +7076,7 @@ Address CodeGeneratorX86::LiteralCaseTable(HX86PackedSwitch* switch_instr,
// TODO: target as memory.
void CodeGeneratorX86::MoveFromReturnRegister(Location target, Primitive::Type type) {
if (!target.IsValid()) {
- DCHECK(type == Primitive::kPrimVoid);
+ DCHECK_EQ(type, Primitive::kPrimVoid);
return;
}
diff --git a/compiler/optimizing/code_generator_x86.h b/compiler/optimizing/code_generator_x86.h
index f9403a67c0..712179920b 100644
--- a/compiler/optimizing/code_generator_x86.h
+++ b/compiler/optimizing/code_generator_x86.h
@@ -219,11 +219,44 @@ class InstructionCodeGeneratorX86 : public HGraphVisitor {
void GenerateShlLong(const Location& loc, int shift);
void GenerateShrLong(const Location& loc, int shift);
void GenerateUShrLong(const Location& loc, int shift);
- void GenerateMemoryBarrier(MemBarrierKind kind);
+
void HandleFieldSet(HInstruction* instruction,
const FieldInfo& field_info,
bool value_can_be_null);
void HandleFieldGet(HInstruction* instruction, const FieldInfo& field_info);
+
+ // Generate a heap reference load using one register `out`:
+ //
+ // out <- *(out + offset)
+ //
+ // while honoring heap poisoning and/or read barriers (if any).
+ // Register `temp` is used when generating a read barrier.
+ void GenerateReferenceLoadOneRegister(HInstruction* instruction,
+ Location out,
+ uint32_t offset,
+ Location temp);
+ // Generate a heap reference load using two different registers
+ // `out` and `obj`:
+ //
+ // out <- *(obj + offset)
+ //
+ // while honoring heap poisoning and/or read barriers (if any).
+ // Register `temp` is used when generating a Baker's read barrier.
+ void GenerateReferenceLoadTwoRegisters(HInstruction* instruction,
+ Location out,
+ Location obj,
+ uint32_t offset,
+ Location temp);
+ // Generate a GC root reference load:
+ //
+ // root <- *(obj + offset)
+ //
+ // while honoring read barriers (if any).
+ void GenerateGcRootFieldLoad(HInstruction* instruction,
+ Location root,
+ Register obj,
+ uint32_t offset);
+
// Push value to FPU stack. `is_fp` specifies whether the value is floating point or not.
// `is_wide` specifies whether it is long/double or not.
void PushOntoFPStack(Location source, uint32_t temp_offset,
@@ -364,6 +397,8 @@ class CodeGeneratorX86 : public CodeGenerator {
Register value,
bool value_can_be_null);
+ void GenerateMemoryBarrier(MemBarrierKind kind);
+
Label* GetLabelOf(HBasicBlock* block) const {
return CommonGetLabelOf<Label>(block_labels_, block);
}
@@ -405,7 +440,26 @@ class CodeGeneratorX86 : public CodeGenerator {
void Finalize(CodeAllocator* allocator) OVERRIDE;
- // Generate a read barrier for a heap reference within `instruction`.
+ // Fast path implementation of ReadBarrier::Barrier for a heap
+ // reference field load when Baker's read barriers are used.
+ void GenerateFieldLoadWithBakerReadBarrier(HInstruction* instruction,
+ Location out,
+ Register obj,
+ uint32_t offset,
+ Location temp,
+ bool needs_null_check);
+ // Fast path implementation of ReadBarrier::Barrier for a heap
+ // reference array load when Baker's read barriers are used.
+ void GenerateArrayLoadWithBakerReadBarrier(HInstruction* instruction,
+ Location out,
+ Register obj,
+ uint32_t data_offset,
+ Location index,
+ Location temp,
+ bool needs_null_check);
+
+ // Generate a read barrier for a heap reference within `instruction`
+ // using a slow path.
//
// A read barrier for an object reference read from the heap is
// implemented as a call to the artReadBarrierSlow runtime entry
@@ -422,23 +476,25 @@ class CodeGeneratorX86 : public CodeGenerator {
// When `index` is provided (i.e. for array accesses), the offset
// value passed to artReadBarrierSlow is adjusted to take `index`
// into account.
- void GenerateReadBarrier(HInstruction* instruction,
- Location out,
- Location ref,
- Location obj,
- uint32_t offset,
- Location index = Location::NoLocation());
-
- // If read barriers are enabled, generate a read barrier for a heap reference.
- // If heap poisoning is enabled, also unpoison the reference in `out`.
- void MaybeGenerateReadBarrier(HInstruction* instruction,
- Location out,
- Location ref,
- Location obj,
- uint32_t offset,
- Location index = Location::NoLocation());
-
- // Generate a read barrier for a GC root within `instruction`.
+ void GenerateReadBarrierSlow(HInstruction* instruction,
+ Location out,
+ Location ref,
+ Location obj,
+ uint32_t offset,
+ Location index = Location::NoLocation());
+
+ // If read barriers are enabled, generate a read barrier for a heap
+ // reference using a slow path. If heap poisoning is enabled, also
+ // unpoison the reference in `out`.
+ void MaybeGenerateReadBarrierSlow(HInstruction* instruction,
+ Location out,
+ Location ref,
+ Location obj,
+ uint32_t offset,
+ Location index = Location::NoLocation());
+
+ // Generate a read barrier for a GC root within `instruction` using
+ // a slow path.
//
// A read barrier for an object reference GC root is implemented as
// a call to the artReadBarrierForRootSlow runtime entry point,
@@ -448,9 +504,18 @@ class CodeGeneratorX86 : public CodeGenerator {
//
// The `out` location contains the value returned by
// artReadBarrierForRootSlow.
- void GenerateReadBarrierForRoot(HInstruction* instruction, Location out, Location root);
+ void GenerateReadBarrierForRootSlow(HInstruction* instruction, Location out, Location root);
private:
+ // Factored implementation of GenerateFieldLoadWithBakerReadBarrier
+ // and GenerateArrayLoadWithBakerReadBarrier.
+ void GenerateReferenceLoadWithBakerReadBarrier(HInstruction* instruction,
+ Location ref,
+ Register obj,
+ const Address& src,
+ Location temp,
+ bool needs_null_check);
+
Register GetInvokeStaticOrDirectExtraParameter(HInvokeStaticOrDirect* invoke, Register temp);
struct PcRelativeDexCacheAccessInfo {
diff --git a/compiler/optimizing/intrinsics_x86.cc b/compiler/optimizing/intrinsics_x86.cc
index 422bb8928d..fd454d8322 100644
--- a/compiler/optimizing/intrinsics_x86.cc
+++ b/compiler/optimizing/intrinsics_x86.cc
@@ -1790,12 +1790,27 @@ static void GenUnsafeGet(HInvoke* invoke,
Location output_loc = locations->Out();
switch (type) {
- case Primitive::kPrimInt:
- case Primitive::kPrimNot: {
+ case Primitive::kPrimInt: {
Register output = output_loc.AsRegister<Register>();
__ movl(output, Address(base, offset, ScaleFactor::TIMES_1, 0));
- if (type == Primitive::kPrimNot) {
- codegen->MaybeGenerateReadBarrier(invoke, output_loc, output_loc, base_loc, 0U, offset_loc);
+ break;
+ }
+
+ case Primitive::kPrimNot: {
+ Register output = output_loc.AsRegister<Register>();
+ if (kEmitCompilerReadBarrier) {
+ if (kUseBakerReadBarrier) {
+ Location temp = locations->GetTemp(0);
+ codegen->GenerateArrayLoadWithBakerReadBarrier(
+ invoke, output_loc, base, 0U, offset_loc, temp, /* needs_null_check */ false);
+ } else {
+ __ movl(output, Address(base, offset, ScaleFactor::TIMES_1, 0));
+ codegen->GenerateReadBarrierSlow(
+ invoke, output_loc, output_loc, base_loc, 0U, offset_loc);
+ }
+ } else {
+ __ movl(output, Address(base, offset, ScaleFactor::TIMES_1, 0));
+ __ MaybeUnpoisonHeapReference(output);
}
break;
}
@@ -1823,8 +1838,10 @@ static void GenUnsafeGet(HInvoke* invoke,
}
}
-static void CreateIntIntIntToIntLocations(ArenaAllocator* arena, HInvoke* invoke,
- bool is_long, bool is_volatile) {
+static void CreateIntIntIntToIntLocations(ArenaAllocator* arena,
+ HInvoke* invoke,
+ Primitive::Type type,
+ bool is_volatile) {
bool can_call = kEmitCompilerReadBarrier &&
(invoke->GetIntrinsic() == Intrinsics::kUnsafeGetObject ||
invoke->GetIntrinsic() == Intrinsics::kUnsafeGetObjectVolatile);
@@ -1836,7 +1853,7 @@ static void CreateIntIntIntToIntLocations(ArenaAllocator* arena, HInvoke* invoke
locations->SetInAt(0, Location::NoLocation()); // Unused receiver.
locations->SetInAt(1, Location::RequiresRegister());
locations->SetInAt(2, Location::RequiresRegister());
- if (is_long) {
+ if (type == Primitive::kPrimLong) {
if (is_volatile) {
// Need to use XMM to read volatile.
locations->AddTemp(Location::RequiresFpuRegister());
@@ -1847,25 +1864,30 @@ static void CreateIntIntIntToIntLocations(ArenaAllocator* arena, HInvoke* invoke
} else {
locations->SetOut(Location::RequiresRegister());
}
+ if (type == Primitive::kPrimNot && kEmitCompilerReadBarrier && kUseBakerReadBarrier) {
+ // We need a temporary register for the read barrier marking slow
+ // path in InstructionCodeGeneratorX86::GenerateArrayLoadWithBakerReadBarrier.
+ locations->AddTemp(Location::RequiresRegister());
+ }
}
void IntrinsicLocationsBuilderX86::VisitUnsafeGet(HInvoke* invoke) {
- CreateIntIntIntToIntLocations(arena_, invoke, /* is_long */ false, /* is_volatile */ false);
+ CreateIntIntIntToIntLocations(arena_, invoke, Primitive::kPrimInt, /* is_volatile */ false);
}
void IntrinsicLocationsBuilderX86::VisitUnsafeGetVolatile(HInvoke* invoke) {
- CreateIntIntIntToIntLocations(arena_, invoke, /* is_long */ false, /* is_volatile */ true);
+ CreateIntIntIntToIntLocations(arena_, invoke, Primitive::kPrimInt, /* is_volatile */ true);
}
void IntrinsicLocationsBuilderX86::VisitUnsafeGetLong(HInvoke* invoke) {
- CreateIntIntIntToIntLocations(arena_, invoke, /* is_long */ true, /* is_volatile */ false);
+ CreateIntIntIntToIntLocations(arena_, invoke, Primitive::kPrimLong, /* is_volatile */ false);
}
void IntrinsicLocationsBuilderX86::VisitUnsafeGetLongVolatile(HInvoke* invoke) {
- CreateIntIntIntToIntLocations(arena_, invoke, /* is_long */ true, /* is_volatile */ true);
+ CreateIntIntIntToIntLocations(arena_, invoke, Primitive::kPrimLong, /* is_volatile */ true);
}
void IntrinsicLocationsBuilderX86::VisitUnsafeGetObject(HInvoke* invoke) {
- CreateIntIntIntToIntLocations(arena_, invoke, /* is_long */ false, /* is_volatile */ false);
+ CreateIntIntIntToIntLocations(arena_, invoke, Primitive::kPrimNot, /* is_volatile */ false);
}
void IntrinsicLocationsBuilderX86::VisitUnsafeGetObjectVolatile(HInvoke* invoke) {
- CreateIntIntIntToIntLocations(arena_, invoke, /* is_long */ false, /* is_volatile */ true);
+ CreateIntIntIntToIntLocations(arena_, invoke, Primitive::kPrimNot, /* is_volatile */ true);
}