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_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);
}