Don't use StringFactory.newEmptyString in compiled code
When compiling debuggable code we would compile a new-instance String
instruction into a StringFactory.newEmptyString invoke. This
additional invoke could be observed using tracing and is inconsistent
with the interpreter, where the string is simply allocated directly.
In order to bring these two modes into alignment we added a new
AllocStringObject quick entrypoint that will be used instead of the
normal AllocObject<...> entrypoints when allocating a string. This
entrypoint directly allocates a new string in the same manner the
interpreter does.
Needs next CL for test to work.
Bug: 110884646
Test: ./test/testrunner/testrunner.py --host --runtime-option=-Xjitthreshold:0 --jit
Test: Manual inspection of compiled code.
Change-Id: I7b4b084bcf7dd9a23485c0e3cd2cd04a04b43d3d
diff --git a/compiler/optimizing/code_generator_arm64.cc b/compiler/optimizing/code_generator_arm64.cc
index 26c9e9f..d1c83ce 100644
--- a/compiler/optimizing/code_generator_arm64.cc
+++ b/compiler/optimizing/code_generator_arm64.cc
@@ -5493,36 +5493,13 @@
LocationSummary* locations = new (GetGraph()->GetAllocator()) LocationSummary(
instruction, LocationSummary::kCallOnMainOnly);
InvokeRuntimeCallingConvention calling_convention;
- if (instruction->IsStringAlloc()) {
- locations->AddTemp(LocationFrom(kArtMethodRegister));
- } else {
- locations->SetInAt(0, LocationFrom(calling_convention.GetRegisterAt(0)));
- }
+ locations->SetInAt(0, LocationFrom(calling_convention.GetRegisterAt(0)));
locations->SetOut(calling_convention.GetReturnLocation(DataType::Type::kReference));
}
void InstructionCodeGeneratorARM64::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.
- Location temp = instruction->GetLocations()->GetTemp(0);
- MemberOffset code_offset = ArtMethod::EntryPointFromQuickCompiledCodeOffset(kArm64PointerSize);
- __ Ldr(XRegisterFrom(temp), MemOperand(tr, QUICK_ENTRY_POINT(pNewEmptyString)));
- __ Ldr(lr, MemOperand(XRegisterFrom(temp), code_offset.Int32Value()));
-
- {
- // Ensure the pc position is recorded immediately after the `blr` instruction.
- ExactAssemblyScope eas(GetVIXLAssembler(),
- kInstructionSize,
- CodeBufferCheckScope::kExactSize);
- __ blr(lr);
- codegen_->RecordPcInfo(instruction, instruction->GetDexPc());
- }
- } else {
- codegen_->InvokeRuntime(instruction->GetEntrypoint(), instruction, instruction->GetDexPc());
- CheckEntrypointTypes<kQuickAllocObjectWithChecks, void*, mirror::Class*>();
- }
+ codegen_->InvokeRuntime(instruction->GetEntrypoint(), instruction, instruction->GetDexPc());
+ CheckEntrypointTypes<kQuickAllocObjectWithChecks, void*, mirror::Class*>();
codegen_->MaybeGenerateMarkingRegisterCheck(/* code */ __LINE__);
}
diff --git a/compiler/optimizing/code_generator_arm_vixl.cc b/compiler/optimizing/code_generator_arm_vixl.cc
index 9e1ef40..deab239 100644
--- a/compiler/optimizing/code_generator_arm_vixl.cc
+++ b/compiler/optimizing/code_generator_arm_vixl.cc
@@ -5479,34 +5479,14 @@
void LocationsBuilderARMVIXL::VisitNewInstance(HNewInstance* instruction) {
LocationSummary* locations = new (GetGraph()->GetAllocator()) LocationSummary(
instruction, LocationSummary::kCallOnMainOnly);
- if (instruction->IsStringAlloc()) {
- locations->AddTemp(LocationFrom(kMethodRegister));
- } else {
- InvokeRuntimeCallingConventionARMVIXL calling_convention;
- locations->SetInAt(0, LocationFrom(calling_convention.GetRegisterAt(0)));
- }
+ 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*>();
- }
+ codegen_->InvokeRuntime(instruction->GetEntrypoint(), instruction, instruction->GetDexPc());
+ CheckEntrypointTypes<kQuickAllocObjectWithChecks, void*, mirror::Class*>();
codegen_->MaybeGenerateMarkingRegisterCheck(/* code */ 11);
}
diff --git a/compiler/optimizing/code_generator_mips.cc b/compiler/optimizing/code_generator_mips.cc
index f0ef30e..c7295e4 100644
--- a/compiler/optimizing/code_generator_mips.cc
+++ b/compiler/optimizing/code_generator_mips.cc
@@ -8701,30 +8701,13 @@
LocationSummary* locations = new (GetGraph()->GetAllocator()) LocationSummary(
instruction, LocationSummary::kCallOnMainOnly);
InvokeRuntimeCallingConvention calling_convention;
- if (instruction->IsStringAlloc()) {
- locations->AddTemp(Location::RegisterLocation(kMethodRegisterArgument));
- } else {
- locations->SetInAt(0, Location::RegisterLocation(calling_convention.GetRegisterAt(0)));
- }
+ locations->SetInAt(0, Location::RegisterLocation(calling_convention.GetRegisterAt(0)));
locations->SetOut(calling_convention.GetReturnLocation(DataType::Type::kReference));
}
void InstructionCodeGeneratorMIPS::VisitNewInstance(HNewInstance* instruction) {
- // Note: if heap poisoning is enabled, the entry point takes care
- // of poisoning the reference.
- if (instruction->IsStringAlloc()) {
- // String is allocated through StringFactory. Call NewEmptyString entry point.
- Register temp = instruction->GetLocations()->GetTemp(0).AsRegister<Register>();
- MemberOffset code_offset = ArtMethod::EntryPointFromQuickCompiledCodeOffset(kMipsPointerSize);
- __ LoadFromOffset(kLoadWord, temp, TR, QUICK_ENTRY_POINT(pNewEmptyString));
- __ LoadFromOffset(kLoadWord, T9, temp, code_offset.Int32Value());
- __ Jalr(T9);
- __ NopIfNoReordering();
- codegen_->RecordPcInfo(instruction, instruction->GetDexPc());
- } else {
- codegen_->InvokeRuntime(instruction->GetEntrypoint(), instruction, instruction->GetDexPc());
- CheckEntrypointTypes<kQuickAllocObjectWithChecks, void*, mirror::Class*>();
- }
+ codegen_->InvokeRuntime(instruction->GetEntrypoint(), instruction, instruction->GetDexPc());
+ CheckEntrypointTypes<kQuickAllocObjectWithChecks, void*, mirror::Class*>();
}
void LocationsBuilderMIPS::VisitNot(HNot* instruction) {
diff --git a/compiler/optimizing/code_generator_mips64.cc b/compiler/optimizing/code_generator_mips64.cc
index 6e72727..ffde45e 100644
--- a/compiler/optimizing/code_generator_mips64.cc
+++ b/compiler/optimizing/code_generator_mips64.cc
@@ -6632,31 +6632,13 @@
LocationSummary* locations = new (GetGraph()->GetAllocator()) LocationSummary(
instruction, LocationSummary::kCallOnMainOnly);
InvokeRuntimeCallingConvention calling_convention;
- if (instruction->IsStringAlloc()) {
- locations->AddTemp(Location::RegisterLocation(kMethodRegisterArgument));
- } else {
- locations->SetInAt(0, Location::RegisterLocation(calling_convention.GetRegisterAt(0)));
- }
+ locations->SetInAt(0, Location::RegisterLocation(calling_convention.GetRegisterAt(0)));
locations->SetOut(calling_convention.GetReturnLocation(DataType::Type::kReference));
}
void InstructionCodeGeneratorMIPS64::VisitNewInstance(HNewInstance* instruction) {
- // Note: if heap poisoning is enabled, the entry point takes care
- // of poisoning the reference.
- if (instruction->IsStringAlloc()) {
- // String is allocated through StringFactory. Call NewEmptyString entry point.
- GpuRegister temp = instruction->GetLocations()->GetTemp(0).AsRegister<GpuRegister>();
- MemberOffset code_offset =
- ArtMethod::EntryPointFromQuickCompiledCodeOffset(kMips64PointerSize);
- __ LoadFromOffset(kLoadDoubleword, temp, TR, QUICK_ENTRY_POINT(pNewEmptyString));
- __ LoadFromOffset(kLoadDoubleword, T9, temp, code_offset.Int32Value());
- __ Jalr(T9);
- __ Nop();
- codegen_->RecordPcInfo(instruction, instruction->GetDexPc());
- } else {
- codegen_->InvokeRuntime(instruction->GetEntrypoint(), instruction, instruction->GetDexPc());
- CheckEntrypointTypes<kQuickAllocObjectWithChecks, void*, mirror::Class*>();
- }
+ codegen_->InvokeRuntime(instruction->GetEntrypoint(), instruction, instruction->GetDexPc());
+ CheckEntrypointTypes<kQuickAllocObjectWithChecks, void*, mirror::Class*>();
}
void LocationsBuilderMIPS64::VisitNot(HNot* instruction) {
diff --git a/compiler/optimizing/code_generator_x86.cc b/compiler/optimizing/code_generator_x86.cc
index d189476..1c0d283 100644
--- a/compiler/optimizing/code_generator_x86.cc
+++ b/compiler/optimizing/code_generator_x86.cc
@@ -4496,29 +4496,14 @@
LocationSummary* locations = new (GetGraph()->GetAllocator()) LocationSummary(
instruction, LocationSummary::kCallOnMainOnly);
locations->SetOut(Location::RegisterLocation(EAX));
- if (instruction->IsStringAlloc()) {
- locations->AddTemp(Location::RegisterLocation(kMethodRegisterArgument));
- } else {
- InvokeRuntimeCallingConvention calling_convention;
- locations->SetInAt(0, Location::RegisterLocation(calling_convention.GetRegisterAt(0)));
- }
+ InvokeRuntimeCallingConvention calling_convention;
+ locations->SetInAt(0, Location::RegisterLocation(calling_convention.GetRegisterAt(0)));
}
void InstructionCodeGeneratorX86::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.
- Register temp = instruction->GetLocations()->GetTemp(0).AsRegister<Register>();
- MemberOffset code_offset = ArtMethod::EntryPointFromQuickCompiledCodeOffset(kX86PointerSize);
- __ fs()->movl(temp, Address::Absolute(QUICK_ENTRY_POINT(pNewEmptyString)));
- __ call(Address(temp, code_offset.Int32Value()));
- codegen_->RecordPcInfo(instruction, instruction->GetDexPc());
- } else {
- codegen_->InvokeRuntime(instruction->GetEntrypoint(), instruction, instruction->GetDexPc());
- CheckEntrypointTypes<kQuickAllocObjectWithChecks, void*, mirror::Class*>();
- DCHECK(!codegen_->IsLeafMethod());
- }
+ codegen_->InvokeRuntime(instruction->GetEntrypoint(), instruction, instruction->GetDexPc());
+ CheckEntrypointTypes<kQuickAllocObjectWithChecks, void*, mirror::Class*>();
+ DCHECK(!codegen_->IsLeafMethod());
}
void LocationsBuilderX86::VisitNewArray(HNewArray* instruction) {
diff --git a/compiler/optimizing/code_generator_x86_64.cc b/compiler/optimizing/code_generator_x86_64.cc
index bea3da0..3073be6 100644
--- a/compiler/optimizing/code_generator_x86_64.cc
+++ b/compiler/optimizing/code_generator_x86_64.cc
@@ -4343,29 +4343,14 @@
LocationSummary* locations = new (GetGraph()->GetAllocator()) LocationSummary(
instruction, LocationSummary::kCallOnMainOnly);
InvokeRuntimeCallingConvention calling_convention;
- if (instruction->IsStringAlloc()) {
- locations->AddTemp(Location::RegisterLocation(kMethodRegisterArgument));
- } else {
- locations->SetInAt(0, Location::RegisterLocation(calling_convention.GetRegisterAt(0)));
- }
+ locations->SetInAt(0, Location::RegisterLocation(calling_convention.GetRegisterAt(0)));
locations->SetOut(Location::RegisterLocation(RAX));
}
void InstructionCodeGeneratorX86_64::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.
- CpuRegister temp = instruction->GetLocations()->GetTemp(0).AsRegister<CpuRegister>();
- MemberOffset code_offset = ArtMethod::EntryPointFromQuickCompiledCodeOffset(kX86_64PointerSize);
- __ gs()->movq(temp, Address::Absolute(QUICK_ENTRY_POINT(pNewEmptyString), /* no_rip */ true));
- __ call(Address(temp, code_offset.SizeValue()));
- codegen_->RecordPcInfo(instruction, instruction->GetDexPc());
- } else {
- codegen_->InvokeRuntime(instruction->GetEntrypoint(), instruction, instruction->GetDexPc());
- CheckEntrypointTypes<kQuickAllocObjectWithChecks, void*, mirror::Class*>();
- DCHECK(!codegen_->IsLeafMethod());
- }
+ codegen_->InvokeRuntime(instruction->GetEntrypoint(), instruction, instruction->GetDexPc());
+ CheckEntrypointTypes<kQuickAllocObjectWithChecks, void*, mirror::Class*>();
+ DCHECK(!codegen_->IsLeafMethod());
}
void LocationsBuilderX86_64::VisitNewArray(HNewArray* instruction) {
diff --git a/compiler/optimizing/instruction_builder.cc b/compiler/optimizing/instruction_builder.cc
index 731accd..ba160e5 100644
--- a/compiler/optimizing/instruction_builder.cc
+++ b/compiler/optimizing/instruction_builder.cc
@@ -1075,6 +1075,10 @@
if (load_class->NeedsAccessCheck() || klass->IsFinalizable() || !klass->IsInstantiable()) {
entrypoint = kQuickAllocObjectWithChecks;
}
+ // We will always be able to resolve the string class since it is in the BCP.
+ if (!klass.IsNull() && klass->IsStringClass()) {
+ entrypoint = kQuickAllocStringObject;
+ }
// Consider classes we haven't resolved as potentially finalizable.
bool finalizable = (klass == nullptr) || klass->IsFinalizable();
diff --git a/compiler/optimizing/nodes.cc b/compiler/optimizing/nodes.cc
index d243331..50ce755 100644
--- a/compiler/optimizing/nodes.cc
+++ b/compiler/optimizing/nodes.cc
@@ -2892,8 +2892,7 @@
}
bool HNewInstance::IsStringAlloc() const {
- ScopedObjectAccess soa(Thread::Current());
- return GetReferenceTypeInfo().IsStringClass();
+ return GetEntrypoint() == kQuickAllocStringObject;
}
bool HInvoke::NeedsEnvironment() const {
diff --git a/compiler/utils/assembler_thumb_test_expected.cc.inc b/compiler/utils/assembler_thumb_test_expected.cc.inc
index e76e98a..85e4326 100644
--- a/compiler/utils/assembler_thumb_test_expected.cc.inc
+++ b/compiler/utils/assembler_thumb_test_expected.cc.inc
@@ -153,7 +153,7 @@
" 21c: f8d9 8034 ldr.w r8, [r9, #52] ; 0x34\n",
" 220: 4770 bx lr\n",
" 222: 4660 mov r0, ip\n",
- " 224: f8d9 c2d0 ldr.w ip, [r9, #720] ; 0x2d0\n",
+ " 224: f8d9 c2d4 ldr.w ip, [r9, #724] ; 0x2d4\n",
" 228: 47e0 blx ip\n",
nullptr
};