Improve HLoadClass code generation.
For classes in the boot image, use either direct pointers
or PC-relative addresses. For other classes, use PC-relative
access to the dex cache arrays for AOT and direct address of
the type's dex cache slot for JIT.
For aosp_flounder-userdebug:
- 32-bit boot.oat: -252KiB (-0.3%)
- 64-bit boot.oat: -412KiB (-0.4%)
- 32-bit dalvik cache total: -392KiB (-0.4%)
- 64-bit dalvik-cache total: -2312KiB (-1.0%)
(contains more files than the 32-bit dalvik cache)
For aosp_flounder-userdebug forced to compile PIC:
- 32-bit boot.oat: -124KiB (-0.2%)
- 64-bit boot.oat: -420KiB (-0.5%)
- 32-bit dalvik cache total: -136KiB (-0.1%)
- 64-bit dalvik-cache total: -1136KiB (-0.5%)
(contains more files than the 32-bit dalvik cache)
Bug: 27950288
Change-Id: I4da991a4b7e53c63c92558b97923d18092acf139
diff --git a/compiler/optimizing/code_generator_x86_64.cc b/compiler/optimizing/code_generator_x86_64.cc
index 135f0c4..ccfb181 100644
--- a/compiler/optimizing/code_generator_x86_64.cc
+++ b/compiler/optimizing/code_generator_x86_64.cc
@@ -894,6 +894,11 @@
__ Bind(&string_patches_.back().label);
}
+void CodeGeneratorX86_64::RecordTypePatch(HLoadClass* load_class) {
+ type_patches_.emplace_back(load_class->GetDexFile(), load_class->GetTypeIndex());
+ __ Bind(&type_patches_.back().label);
+}
+
Label* CodeGeneratorX86_64::NewPcRelativeDexCacheArrayPatch(const DexFile& dex_file,
uint32_t element_offset) {
// Add a patch entry and return the label.
@@ -908,7 +913,8 @@
relative_call_patches_.size() +
pc_relative_dex_cache_patches_.size() +
simple_patches_.size() +
- string_patches_.size();
+ string_patches_.size() +
+ type_patches_.size();
linker_patches->reserve(size);
// The label points to the end of the "movl" insn but the literal offset for method
// patch needs to point to the embedded constant which occupies the last 4 bytes.
@@ -944,6 +950,14 @@
info.label.Position(),
info.string_index));
}
+ for (const TypePatchInfo<Label>& info : type_patches_) {
+ // These are always PC-relative, see GetSupportedLoadClassKind().
+ uint32_t literal_offset = info.label.Position() - kLabelPositionToLiteralOffsetAdjustment;
+ linker_patches->push_back(LinkerPatch::RelativeTypePatch(literal_offset,
+ &info.dex_file,
+ info.label.Position(),
+ info.type_index));
+ }
}
void CodeGeneratorX86_64::DumpCoreRegister(std::ostream& stream, int reg) const {
@@ -1023,6 +1037,7 @@
pc_relative_dex_cache_patches_(graph->GetArena()->Adapter(kArenaAllocCodeGenerator)),
simple_patches_(graph->GetArena()->Adapter(kArenaAllocCodeGenerator)),
string_patches_(graph->GetArena()->Adapter(kArenaAllocCodeGenerator)),
+ type_patches_(graph->GetArena()->Adapter(kArenaAllocCodeGenerator)),
fixups_to_jump_tables_(graph->GetArena()->Adapter(kArenaAllocCodeGenerator)) {
AddAllocatedRegister(Location::RegisterLocation(kFakeReturnRegister));
}
@@ -5317,13 +5332,64 @@
// No need for memory fence, thanks to the x86-64 memory model.
}
+HLoadClass::LoadKind CodeGeneratorX86_64::GetSupportedLoadClassKind(
+ HLoadClass::LoadKind desired_class_load_kind) {
+ if (kEmitCompilerReadBarrier) {
+ switch (desired_class_load_kind) {
+ case HLoadClass::LoadKind::kBootImageLinkTimeAddress:
+ case HLoadClass::LoadKind::kBootImageLinkTimePcRelative:
+ case HLoadClass::LoadKind::kBootImageAddress:
+ // TODO: Implement for read barrier.
+ return HLoadClass::LoadKind::kDexCacheViaMethod;
+ default:
+ break;
+ }
+ }
+ switch (desired_class_load_kind) {
+ case HLoadClass::LoadKind::kReferrersClass:
+ break;
+ case HLoadClass::LoadKind::kBootImageLinkTimeAddress:
+ DCHECK(!GetCompilerOptions().GetCompilePic());
+ // We prefer the always-available RIP-relative address for the x86-64 boot image.
+ return HLoadClass::LoadKind::kBootImageLinkTimePcRelative;
+ case HLoadClass::LoadKind::kBootImageLinkTimePcRelative:
+ DCHECK(GetCompilerOptions().GetCompilePic());
+ break;
+ case HLoadClass::LoadKind::kBootImageAddress:
+ break;
+ case HLoadClass::LoadKind::kDexCacheAddress:
+ DCHECK(Runtime::Current()->UseJitCompilation());
+ break;
+ case HLoadClass::LoadKind::kDexCachePcRelative:
+ DCHECK(!Runtime::Current()->UseJitCompilation());
+ break;
+ case HLoadClass::LoadKind::kDexCacheViaMethod:
+ break;
+ }
+ return desired_class_load_kind;
+}
+
void LocationsBuilderX86_64::VisitLoadClass(HLoadClass* cls) {
- InvokeRuntimeCallingConvention calling_convention;
- CodeGenerator::CreateLoadClassLocationSummary(
- cls,
- Location::RegisterLocation(calling_convention.GetRegisterAt(0)),
- Location::RegisterLocation(RAX),
- /* code_generator_supports_read_barrier */ true);
+ if (cls->NeedsAccessCheck()) {
+ InvokeRuntimeCallingConvention calling_convention;
+ CodeGenerator::CreateLoadClassLocationSummary(
+ cls,
+ Location::RegisterLocation(calling_convention.GetRegisterAt(0)),
+ Location::RegisterLocation(RAX),
+ /* code_generator_supports_read_barrier */ true);
+ return;
+ }
+
+ LocationSummary::CallKind call_kind = (cls->NeedsEnvironment() || kEmitCompilerReadBarrier)
+ ? LocationSummary::kCallOnSlowPath
+ : LocationSummary::kNoCall;
+ LocationSummary* locations = new (GetGraph()->GetArena()) LocationSummary(cls, call_kind);
+ HLoadClass::LoadKind load_kind = cls->GetLoadKind();
+ if (load_kind == HLoadClass::LoadKind::kReferrersClass ||
+ load_kind == HLoadClass::LoadKind::kDexCacheViaMethod) {
+ locations->SetInAt(0, Location::RequiresRegister());
+ }
+ locations->SetOut(Location::RequiresRegister());
}
void InstructionCodeGeneratorX86_64::VisitLoadClass(HLoadClass* cls) {
@@ -5340,37 +5406,86 @@
Location out_loc = locations->Out();
CpuRegister out = out_loc.AsRegister<CpuRegister>();
- CpuRegister current_method = locations->InAt(0).AsRegister<CpuRegister>();
- if (cls->IsReferrersClass()) {
- DCHECK(!cls->CanCallRuntime());
- DCHECK(!cls->MustGenerateClinitCheck());
- // /* GcRoot<mirror::Class> */ out = current_method->declaring_class_
- GenerateGcRootFieldLoad(
- cls, out_loc, Address(current_method, ArtMethod::DeclaringClassOffset().Int32Value()));
- } else {
- // /* GcRoot<mirror::Class>[] */ out =
- // current_method.ptr_sized_fields_->dex_cache_resolved_types_
- __ movq(out, Address(current_method,
- ArtMethod::DexCacheResolvedTypesOffset(kX86_64PointerSize).Int32Value()));
- // /* GcRoot<mirror::Class> */ out = out[type_index]
- GenerateGcRootFieldLoad(
- cls, out_loc, Address(out, CodeGenerator::GetCacheOffset(cls->GetTypeIndex())));
-
- if (!cls->IsInDexCache() || cls->MustGenerateClinitCheck()) {
- DCHECK(cls->CanCallRuntime());
- SlowPathCode* slow_path = new (GetGraph()->GetArena()) LoadClassSlowPathX86_64(
- cls, cls, cls->GetDexPc(), cls->MustGenerateClinitCheck());
- codegen_->AddSlowPath(slow_path);
- if (!cls->IsInDexCache()) {
- __ testl(out, out);
- __ j(kEqual, slow_path->GetEntryLabel());
- }
- if (cls->MustGenerateClinitCheck()) {
- GenerateClassInitializationCheck(slow_path, out);
+ bool generate_null_check = false;
+ switch (cls->GetLoadKind()) {
+ case HLoadClass::LoadKind::kReferrersClass: {
+ DCHECK(!cls->CanCallRuntime());
+ DCHECK(!cls->MustGenerateClinitCheck());
+ // /* GcRoot<mirror::Class> */ out = current_method->declaring_class_
+ CpuRegister current_method = locations->InAt(0).AsRegister<CpuRegister>();
+ GenerateGcRootFieldLoad(
+ cls, out_loc, Address(current_method, ArtMethod::DeclaringClassOffset().Int32Value()));
+ break;
+ }
+ case HLoadClass::LoadKind::kBootImageLinkTimePcRelative:
+ DCHECK(!kEmitCompilerReadBarrier);
+ __ leal(out, Address::Absolute(CodeGeneratorX86_64::kDummy32BitOffset, /* no_rip */ false));
+ codegen_->RecordTypePatch(cls);
+ break;
+ case HLoadClass::LoadKind::kBootImageAddress: {
+ DCHECK(!kEmitCompilerReadBarrier);
+ DCHECK_NE(cls->GetAddress(), 0u);
+ uint32_t address = dchecked_integral_cast<uint32_t>(cls->GetAddress());
+ __ movl(out, Immediate(address)); // Zero-extended.
+ codegen_->RecordSimplePatch();
+ break;
+ }
+ case HLoadClass::LoadKind::kDexCacheAddress: {
+ DCHECK_NE(cls->GetAddress(), 0u);
+ // /* GcRoot<mirror::Class> */ out = *address
+ if (IsUint<32>(cls->GetAddress())) {
+ Address address = Address::Absolute(cls->GetAddress(), /* no_rip */ true);
+ GenerateGcRootFieldLoad(cls, out_loc, address);
} else {
- __ Bind(slow_path->GetExitLabel());
+ // TODO: Consider using opcode A1, i.e. movl eax, moff32 (with 64-bit address).
+ __ movq(out, Immediate(cls->GetAddress()));
+ GenerateGcRootFieldLoad(cls, out_loc, Address(out, 0));
}
+ generate_null_check = !cls->IsInDexCache();
+ break;
+ }
+ case HLoadClass::LoadKind::kDexCachePcRelative: {
+ uint32_t offset = cls->GetDexCacheElementOffset();
+ Label* fixup_label = codegen_->NewPcRelativeDexCacheArrayPatch(cls->GetDexFile(), offset);
+ Address address = Address::Absolute(CodeGeneratorX86_64::kDummy32BitOffset,
+ /* no_rip */ false);
+ // /* GcRoot<mirror::Class> */ out = *address /* PC-relative */
+ GenerateGcRootFieldLoad(cls, out_loc, address, fixup_label);
+ generate_null_check = !cls->IsInDexCache();
+ break;
+ }
+ case HLoadClass::LoadKind::kDexCacheViaMethod: {
+ // /* GcRoot<mirror::Class>[] */ out =
+ // current_method.ptr_sized_fields_->dex_cache_resolved_types_
+ CpuRegister current_method = locations->InAt(0).AsRegister<CpuRegister>();
+ __ movq(out,
+ Address(current_method,
+ ArtMethod::DexCacheResolvedTypesOffset(kX86_64PointerSize).Int32Value()));
+ // /* GcRoot<mirror::Class> */ out = out[type_index]
+ GenerateGcRootFieldLoad(
+ cls, out_loc, Address(out, CodeGenerator::GetCacheOffset(cls->GetTypeIndex())));
+ generate_null_check = !cls->IsInDexCache();
+ break;
+ }
+ default:
+ LOG(FATAL) << "Unexpected load kind: " << cls->GetLoadKind();
+ UNREACHABLE();
+ }
+
+ if (generate_null_check || cls->MustGenerateClinitCheck()) {
+ DCHECK(cls->CanCallRuntime());
+ SlowPathCode* slow_path = new (GetGraph()->GetArena()) LoadClassSlowPathX86_64(
+ cls, cls, cls->GetDexPc(), cls->MustGenerateClinitCheck());
+ codegen_->AddSlowPath(slow_path);
+ if (generate_null_check) {
+ __ testl(out, out);
+ __ j(kEqual, slow_path->GetEntryLabel());
+ }
+ if (cls->MustGenerateClinitCheck()) {
+ GenerateClassInitializationCheck(slow_path, out);
+ } else {
+ __ Bind(slow_path->GetExitLabel());
}
}
}
@@ -5461,6 +5576,7 @@
}
case HLoadString::LoadKind::kDexCacheAddress: {
DCHECK_NE(load->GetAddress(), 0u);
+ // /* GcRoot<mirror::String> */ out = *address
if (IsUint<32>(load->GetAddress())) {
Address address = Address::Absolute(load->GetAddress(), /* no_rip */ true);
GenerateGcRootFieldLoad(load, out_loc, address);
@@ -5476,6 +5592,7 @@
Label* fixup_label = codegen_->NewPcRelativeDexCacheArrayPatch(load->GetDexFile(), offset);
Address address = Address::Absolute(CodeGeneratorX86_64::kDummy32BitOffset,
/* no_rip */ false);
+ // /* GcRoot<mirror::String> */ out = *address /* PC-relative */
GenerateGcRootFieldLoad(load, out_loc, address, fixup_label);
break;
}