Revert "Revert "X86: Use locked add rather than mfence""
This reverts commit 0da3b9117706760e8722029f407da6d0297cc943.
Fix a compilation failure that slipped in somehow.
Change-Id: Ide8681cdc921febb296ea47aa282cc195f154049
diff --git a/compiler/dex/quick/x86/assemble_x86.cc b/compiler/dex/quick/x86/assemble_x86.cc
index e5d3841..1c2a619 100644
--- a/compiler/dex/quick/x86/assemble_x86.cc
+++ b/compiler/dex/quick/x86/assemble_x86.cc
@@ -508,6 +508,7 @@
{ kX86Lfence, kReg, NO_OPERAND, { 0, 0, 0x0F, 0xAE, 0, 5, 0, 0, false }, "Lfence", "" },
{ kX86Mfence, kReg, NO_OPERAND, { 0, 0, 0x0F, 0xAE, 0, 6, 0, 0, false }, "Mfence", "" },
{ kX86Sfence, kReg, NO_OPERAND, { 0, 0, 0x0F, 0xAE, 0, 7, 0, 0, false }, "Sfence", "" },
+ { kX86LockAdd32MI8, kMemImm, IS_LOAD | IS_STORE | IS_TERTIARY_OP | REG_USE0 | SETS_CCODES, { 0xF0, 0, 0x83, 0x0, 0x0, 0, 0, 1, false }, "LockAdd32MI8", "[!0r+!1d],!2d" },
EXT_0F_ENCODING_MAP(Imul16, 0x66, 0xAF, REG_USE0 | REG_DEF0 | SETS_CCODES),
EXT_0F_ENCODING_MAP(Imul32, 0x00, 0xAF, REG_USE0 | REG_DEF0 | SETS_CCODES),
diff --git a/compiler/dex/quick/x86/target_x86.cc b/compiler/dex/quick/x86/target_x86.cc
index 75f3fef..4ff7993 100755
--- a/compiler/dex/quick/x86/target_x86.cc
+++ b/compiler/dex/quick/x86/target_x86.cc
@@ -20,7 +20,7 @@
#include <inttypes.h>
#include <string>
-#include "arch/instruction_set_features.h"
+#include "arch/x86/instruction_set_features_x86.h"
#include "art_method.h"
#include "backend_x86.h"
#include "base/logging.h"
@@ -585,6 +585,8 @@
case kX86LockCmpxchgAR:
case kX86LockCmpxchg64M:
case kX86LockCmpxchg64A:
+ case kX86LockCmpxchg64AR:
+ case kX86LockAdd32MI8:
case kX86XchgMR:
case kX86Mfence:
// Atomic memory instructions provide full barrier.
@@ -598,7 +600,9 @@
}
bool X86Mir2Lir::GenMemBarrier(MemBarrierKind barrier_kind) {
- if (!cu_->compiler_driver->GetInstructionSetFeatures()->IsSmp()) {
+ const X86InstructionSetFeatures* features =
+ cu_->compiler_driver->GetInstructionSetFeatures()->AsX86InstructionSetFeatures();
+ if (!features->IsSmp()) {
return false;
}
// Start off with using the last LIR as the barrier. If it is not enough, then we will update it.
@@ -610,20 +614,34 @@
* All other barriers (LoadAny, AnyStore, StoreStore) are nops due to the x86 memory model.
* For those cases, all we need to ensure is that there is a scheduling barrier in place.
*/
+ const RegStorage rs_rSP = cu_->target64 ? rs_rX86_SP_64 : rs_rX86_SP_32;
+ bool use_locked_add = features->PrefersLockedAddSynchronization();
if (barrier_kind == kAnyAny) {
- // If no LIR exists already that can be used a barrier, then generate an mfence.
+ // If no LIR exists already that can be used a barrier, then generate a barrier.
if (mem_barrier == nullptr) {
- mem_barrier = NewLIR0(kX86Mfence);
+ if (use_locked_add) {
+ mem_barrier = NewLIR3(kX86LockAdd32MI8, rs_rSP.GetReg(), 0, 0);
+ } else {
+ mem_barrier = NewLIR0(kX86Mfence);
+ }
ret = true;
}
- // If last instruction does not provide full barrier, then insert an mfence.
+ // If last instruction does not provide full barrier, then insert a barrier.
if (ProvidesFullMemoryBarrier(static_cast<X86OpCode>(mem_barrier->opcode)) == false) {
- mem_barrier = NewLIR0(kX86Mfence);
+ if (use_locked_add) {
+ mem_barrier = NewLIR3(kX86LockAdd32MI8, rs_rSP.GetReg(), 0, 0);
+ } else {
+ mem_barrier = NewLIR0(kX86Mfence);
+ }
ret = true;
}
} else if (barrier_kind == kNTStoreStore) {
- mem_barrier = NewLIR0(kX86Sfence);
+ if (use_locked_add) {
+ mem_barrier = NewLIR3(kX86LockAdd32MI8, rs_rSP.GetReg(), 0, 0);
+ } else {
+ mem_barrier = NewLIR0(kX86Sfence);
+ }
ret = true;
}
diff --git a/compiler/dex/quick/x86/x86_lir.h b/compiler/dex/quick/x86/x86_lir.h
index d6a6a60..8cd6574 100644
--- a/compiler/dex/quick/x86/x86_lir.h
+++ b/compiler/dex/quick/x86/x86_lir.h
@@ -606,6 +606,7 @@
// load-from-memory and store-to-memory instructions
kX86Sfence, // memory barrier to serialize all previous
// store-to-memory instructions
+ kX86LockAdd32MI8, // locked add used to serialize memory instructions
Binary0fOpCode(kX86Imul16), // 16bit multiply
Binary0fOpCode(kX86Imul32), // 32bit multiply
Binary0fOpCode(kX86Imul64), // 64bit multiply
diff --git a/compiler/optimizing/code_generator_x86.cc b/compiler/optimizing/code_generator_x86.cc
index bc3256e..e7f7d57 100644
--- a/compiler/optimizing/code_generator_x86.cc
+++ b/compiler/optimizing/code_generator_x86.cc
@@ -4157,7 +4157,7 @@
*/
switch (kind) {
case MemBarrierKind::kAnyAny: {
- __ mfence();
+ MemoryFence();
break;
}
case MemBarrierKind::kAnyStore:
diff --git a/compiler/optimizing/code_generator_x86.h b/compiler/optimizing/code_generator_x86.h
index 7c292fa..ebbe486 100644
--- a/compiler/optimizing/code_generator_x86.h
+++ b/compiler/optimizing/code_generator_x86.h
@@ -17,6 +17,7 @@
#ifndef ART_COMPILER_OPTIMIZING_CODE_GENERATOR_X86_H_
#define ART_COMPILER_OPTIMIZING_CODE_GENERATOR_X86_H_
+#include "arch/x86/instruction_set_features_x86.h"
#include "code_generator.h"
#include "dex/compiler_enums.h"
#include "driver/compiler_options.h"
@@ -496,6 +497,19 @@
// artReadBarrierForRootSlow.
void GenerateReadBarrierForRootSlow(HInstruction* instruction, Location out, Location root);
+ // Ensure that prior stores complete to memory before subsequent loads.
+ // The locked add implementation will avoid serializing device memory, but will
+ // touch (but not change) the top of the stack.
+ // The 'non_temporal' parameter should be used to ensure ordering of non-temporal stores.
+ void MemoryFence(bool non_temporal = false) {
+ if (!non_temporal && isa_features_.PrefersLockedAddSynchronization()) {
+ assembler_.lock()->addl(Address(ESP, 0), Immediate(0));
+ } else {
+ assembler_.mfence();
+ }
+ }
+
+
private:
// Factored implementation of GenerateFieldLoadWithBakerReadBarrier
// and GenerateArrayLoadWithBakerReadBarrier.
diff --git a/compiler/optimizing/code_generator_x86_64.cc b/compiler/optimizing/code_generator_x86_64.cc
index 92cef5f..e0ad062 100644
--- a/compiler/optimizing/code_generator_x86_64.cc
+++ b/compiler/optimizing/code_generator_x86_64.cc
@@ -4029,7 +4029,7 @@
*/
switch (kind) {
case MemBarrierKind::kAnyAny: {
- __ mfence();
+ MemoryFence();
break;
}
case MemBarrierKind::kAnyStore:
diff --git a/compiler/optimizing/code_generator_x86_64.h b/compiler/optimizing/code_generator_x86_64.h
index dda9ea2..e5a487c 100644
--- a/compiler/optimizing/code_generator_x86_64.h
+++ b/compiler/optimizing/code_generator_x86_64.h
@@ -17,6 +17,7 @@
#ifndef ART_COMPILER_OPTIMIZING_CODE_GENERATOR_X86_64_H_
#define ART_COMPILER_OPTIMIZING_CODE_GENERATOR_X86_64_H_
+#include "arch/x86_64/instruction_set_features_x86_64.h"
#include "code_generator.h"
#include "dex/compiler_enums.h"
#include "driver/compiler_options.h"
@@ -479,6 +480,18 @@
int64_t v,
HInstruction* instruction);
+ // Ensure that prior stores complete to memory before subsequent loads.
+ // The locked add implementation will avoid serializing device memory, but will
+ // touch (but not change) the top of the stack. The locked add should not be used for
+ // ordering non-temporal stores.
+ void MemoryFence(bool force_mfence = false) {
+ if (!force_mfence && isa_features_.PrefersLockedAddSynchronization()) {
+ assembler_.lock()->addl(Address(CpuRegister(RSP), 0), Immediate(0));
+ } else {
+ assembler_.mfence();
+ }
+ }
+
private:
// Factored implementation of GenerateFieldLoadWithBakerReadBarrier
// and GenerateArrayLoadWithBakerReadBarrier.
diff --git a/compiler/optimizing/intrinsics_x86.cc b/compiler/optimizing/intrinsics_x86.cc
index fd454d8..74ade7c 100644
--- a/compiler/optimizing/intrinsics_x86.cc
+++ b/compiler/optimizing/intrinsics_x86.cc
@@ -2005,7 +2005,7 @@
}
if (is_volatile) {
- __ mfence();
+ codegen->MemoryFence();
}
if (type == Primitive::kPrimNot) {
diff --git a/compiler/optimizing/intrinsics_x86_64.cc b/compiler/optimizing/intrinsics_x86_64.cc
index ce737e3..6e54dde 100644
--- a/compiler/optimizing/intrinsics_x86_64.cc
+++ b/compiler/optimizing/intrinsics_x86_64.cc
@@ -2080,7 +2080,7 @@
}
if (is_volatile) {
- __ mfence();
+ codegen->MemoryFence();
}
if (type == Primitive::kPrimNot) {