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/*
* Copyright (C) 2015 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include "intrinsics_arm64.h"
#include "arch/arm64/callee_save_frame_arm64.h"
#include "arch/arm64/instruction_set_features_arm64.h"
#include "art_method.h"
#include "base/bit_utils.h"
#include "code_generator_arm64.h"
#include "common_arm64.h"
#include "data_type-inl.h"
#include "entrypoints/quick/quick_entrypoints.h"
#include "heap_poisoning.h"
#include "intrinsics.h"
#include "intrinsics_utils.h"
#include "lock_word.h"
#include "mirror/array-inl.h"
#include "mirror/object_array-inl.h"
#include "mirror/reference.h"
#include "mirror/string-inl.h"
#include "mirror/var_handle.h"
#include "scoped_thread_state_change-inl.h"
#include "thread-current-inl.h"
#include "utils/arm64/assembler_arm64.h"
using namespace vixl::aarch64; // NOLINT(build/namespaces)
// TODO(VIXL): Make VIXL compile with -Wshadow.
#pragma GCC diagnostic push
#pragma GCC diagnostic ignored "-Wshadow"
#include "aarch64/disasm-aarch64.h"
#include "aarch64/macro-assembler-aarch64.h"
#pragma GCC diagnostic pop
namespace art {
namespace arm64 {
using helpers::CPURegisterFrom;
using helpers::DRegisterFrom;
using helpers::HeapOperand;
using helpers::LocationFrom;
using helpers::InputCPURegisterOrZeroRegAt;
using helpers::IsConstantZeroBitPattern;
using helpers::OperandFrom;
using helpers::RegisterFrom;
using helpers::SRegisterFrom;
using helpers::WRegisterFrom;
using helpers::XRegisterFrom;
using helpers::HRegisterFrom;
using helpers::InputRegisterAt;
using helpers::OutputRegister;
namespace {
ALWAYS_INLINE inline MemOperand AbsoluteHeapOperandFrom(Location location, size_t offset = 0) {
return MemOperand(XRegisterFrom(location), offset);
}
} // namespace
MacroAssembler* IntrinsicCodeGeneratorARM64::GetVIXLAssembler() {
return codegen_->GetVIXLAssembler();
}
ArenaAllocator* IntrinsicCodeGeneratorARM64::GetAllocator() {
return codegen_->GetGraph()->GetAllocator();
}
using IntrinsicSlowPathARM64 = IntrinsicSlowPath<InvokeDexCallingConventionVisitorARM64,
SlowPathCodeARM64,
Arm64Assembler>;
#define __ codegen->GetVIXLAssembler()->
// Slow path implementing the SystemArrayCopy intrinsic copy loop with read barriers.
class ReadBarrierSystemArrayCopySlowPathARM64 : public SlowPathCodeARM64 {
public:
ReadBarrierSystemArrayCopySlowPathARM64(HInstruction* instruction, Location tmp)
: SlowPathCodeARM64(instruction), tmp_(tmp) {
DCHECK(kEmitCompilerReadBarrier);
DCHECK(kUseBakerReadBarrier);
}
void EmitNativeCode(CodeGenerator* codegen_in) override {
CodeGeneratorARM64* codegen = down_cast<CodeGeneratorARM64*>(codegen_in);
LocationSummary* locations = instruction_->GetLocations();
DCHECK(locations->CanCall());
DCHECK(instruction_->IsInvokeStaticOrDirect())
<< "Unexpected instruction in read barrier arraycopy slow path: "
<< instruction_->DebugName();
DCHECK(instruction_->GetLocations()->Intrinsified());
DCHECK_EQ(instruction_->AsInvoke()->GetIntrinsic(), Intrinsics::kSystemArrayCopy);
const int32_t element_size = DataType::Size(DataType::Type::kReference);
Register src_curr_addr = XRegisterFrom(locations->GetTemp(0));
Register dst_curr_addr = XRegisterFrom(locations->GetTemp(1));
Register src_stop_addr = XRegisterFrom(locations->GetTemp(2));
Register tmp_reg = WRegisterFrom(tmp_);
__ Bind(GetEntryLabel());
vixl::aarch64::Label slow_copy_loop;
__ Bind(&slow_copy_loop);
__ Ldr(tmp_reg, MemOperand(src_curr_addr, element_size, PostIndex));
codegen->GetAssembler()->MaybeUnpoisonHeapReference(tmp_reg);
// TODO: Inline the mark bit check before calling the runtime?
// tmp_reg = ReadBarrier::Mark(tmp_reg);
// No need to save live registers; it's taken care of by the
// entrypoint. Also, there is no need to update the stack mask,
// as this runtime call will not trigger a garbage collection.
// (See ReadBarrierMarkSlowPathARM64::EmitNativeCode for more
// explanations.)
DCHECK_NE(tmp_.reg(), LR);
DCHECK_NE(tmp_.reg(), WSP);
DCHECK_NE(tmp_.reg(), WZR);
// IP0 is used internally by the ReadBarrierMarkRegX entry point
// as a temporary (and not preserved). It thus cannot be used by
// any live register in this slow path.
DCHECK_NE(LocationFrom(src_curr_addr).reg(), IP0);
DCHECK_NE(LocationFrom(dst_curr_addr).reg(), IP0);
DCHECK_NE(LocationFrom(src_stop_addr).reg(), IP0);
DCHECK_NE(tmp_.reg(), IP0);
DCHECK(0 <= tmp_.reg() && tmp_.reg() < kNumberOfWRegisters) << tmp_.reg();
// TODO: Load the entrypoint once before the loop, instead of
// loading it at every iteration.
int32_t entry_point_offset =
Thread::ReadBarrierMarkEntryPointsOffset<kArm64PointerSize>(tmp_.reg());
// This runtime call does not require a stack map.
codegen->InvokeRuntimeWithoutRecordingPcInfo(entry_point_offset, instruction_, this);
codegen->GetAssembler()->MaybePoisonHeapReference(tmp_reg);
__ Str(tmp_reg, MemOperand(dst_curr_addr, element_size, PostIndex));
__ Cmp(src_curr_addr, src_stop_addr);
__ B(&slow_copy_loop, ne);
__ B(GetExitLabel());
}
const char* GetDescription() const override { return "ReadBarrierSystemArrayCopySlowPathARM64"; }
private:
Location tmp_;
DISALLOW_COPY_AND_ASSIGN(ReadBarrierSystemArrayCopySlowPathARM64);
};
#undef __
bool IntrinsicLocationsBuilderARM64::TryDispatch(HInvoke* invoke) {
Dispatch(invoke);
LocationSummary* res = invoke->GetLocations();
if (res == nullptr) {
return false;
}
return res->Intrinsified();
}
#define __ masm->
static void CreateFPToIntLocations(ArenaAllocator* allocator, HInvoke* invoke) {
LocationSummary* locations =
new (allocator) LocationSummary(invoke, LocationSummary::kNoCall, kIntrinsified);
locations->SetInAt(0, Location::RequiresFpuRegister());
locations->SetOut(Location::RequiresRegister());
}
static void CreateIntToFPLocations(ArenaAllocator* allocator, HInvoke* invoke) {
LocationSummary* locations =
new (allocator) LocationSummary(invoke, LocationSummary::kNoCall, kIntrinsified);
locations->SetInAt(0, Location::RequiresRegister());
locations->SetOut(Location::RequiresFpuRegister());
}
static void MoveFPToInt(LocationSummary* locations, bool is64bit, MacroAssembler* masm) {
Location input = locations->InAt(0);
Location output = locations->Out();
__ Fmov(is64bit ? XRegisterFrom(output) : WRegisterFrom(output),
is64bit ? DRegisterFrom(input) : SRegisterFrom(input));
}
static void MoveIntToFP(LocationSummary* locations, bool is64bit, MacroAssembler* masm) {
Location input = locations->InAt(0);
Location output = locations->Out();
__ Fmov(is64bit ? DRegisterFrom(output) : SRegisterFrom(output),
is64bit ? XRegisterFrom(input) : WRegisterFrom(input));
}
void IntrinsicLocationsBuilderARM64::VisitDoubleDoubleToRawLongBits(HInvoke* invoke) {
CreateFPToIntLocations(allocator_, invoke);
}
void IntrinsicLocationsBuilderARM64::VisitDoubleLongBitsToDouble(HInvoke* invoke) {
CreateIntToFPLocations(allocator_, invoke);
}
void IntrinsicCodeGeneratorARM64::VisitDoubleDoubleToRawLongBits(HInvoke* invoke) {
MoveFPToInt(invoke->GetLocations(), /* is64bit= */ true, GetVIXLAssembler());
}
void IntrinsicCodeGeneratorARM64::VisitDoubleLongBitsToDouble(HInvoke* invoke) {
MoveIntToFP(invoke->GetLocations(), /* is64bit= */ true, GetVIXLAssembler());
}
void IntrinsicLocationsBuilderARM64::VisitFloatFloatToRawIntBits(HInvoke* invoke) {
CreateFPToIntLocations(allocator_, invoke);
}
void IntrinsicLocationsBuilderARM64::VisitFloatIntBitsToFloat(HInvoke* invoke) {
CreateIntToFPLocations(allocator_, invoke);
}
void IntrinsicCodeGeneratorARM64::VisitFloatFloatToRawIntBits(HInvoke* invoke) {
MoveFPToInt(invoke->GetLocations(), /* is64bit= */ false, GetVIXLAssembler());
}
void IntrinsicCodeGeneratorARM64::VisitFloatIntBitsToFloat(HInvoke* invoke) {
MoveIntToFP(invoke->GetLocations(), /* is64bit= */ false, GetVIXLAssembler());
}
static void CreateIntToIntLocations(ArenaAllocator* allocator, HInvoke* invoke) {
LocationSummary* locations =
new (allocator) LocationSummary(invoke, LocationSummary::kNoCall, kIntrinsified);
locations->SetInAt(0, Location::RequiresRegister());
locations->SetOut(Location::RequiresRegister(), Location::kNoOutputOverlap);
}
static void CreateIntIntToIntLocations(ArenaAllocator* allocator, HInvoke* invoke) {
LocationSummary* locations =
new (allocator) LocationSummary(invoke, LocationSummary::kNoCall, kIntrinsified);
locations->SetInAt(0, Location::RequiresRegister());
locations->SetInAt(1, Location::RequiresRegister());
locations->SetOut(Location::RequiresRegister(), Location::kNoOutputOverlap);
}
static void CreateIntIntToIntSlowPathCallLocations(ArenaAllocator* allocator, HInvoke* invoke) {
LocationSummary* locations =
new (allocator) LocationSummary(invoke, LocationSummary::kCallOnSlowPath, kIntrinsified);
locations->SetInAt(0, Location::RequiresRegister());
locations->SetInAt(1, Location::RequiresRegister());
// Force kOutputOverlap; see comments in IntrinsicSlowPath::EmitNativeCode.
locations->SetOut(Location::RequiresRegister(), Location::kOutputOverlap);
}
static void GenerateReverseBytes(MacroAssembler* masm,
DataType::Type type,
CPURegister in,
CPURegister out) {
switch (type) {
case DataType::Type::kUint16:
__ Rev16(out.W(), in.W());
break;
case DataType::Type::kInt16:
__ Rev16(out.W(), in.W());
__ Sxth(out.W(), out.W());
break;
case DataType::Type::kInt32:
__ Rev(out.W(), in.W());
break;
case DataType::Type::kInt64:
__ Rev(out.X(), in.X());
break;
case DataType::Type::kFloat32:
__ Rev(in.W(), in.W()); // Note: Clobbers `in`.
__ Fmov(out.S(), in.W());
break;
case DataType::Type::kFloat64:
__ Rev(in.X(), in.X()); // Note: Clobbers `in`.
__ Fmov(out.D(), in.X());
break;
default:
LOG(FATAL) << "Unexpected type for reverse-bytes: " << type;
UNREACHABLE();
}
}
static void GenReverseBytes(LocationSummary* locations,
DataType::Type type,
MacroAssembler* masm) {
Location in = locations->InAt(0);
Location out = locations->Out();
GenerateReverseBytes(masm, type, CPURegisterFrom(in, type), CPURegisterFrom(out, type));
}
void IntrinsicLocationsBuilderARM64::VisitIntegerReverseBytes(HInvoke* invoke) {
CreateIntToIntLocations(allocator_, invoke);
}
void IntrinsicCodeGeneratorARM64::VisitIntegerReverseBytes(HInvoke* invoke) {
GenReverseBytes(invoke->GetLocations(), DataType::Type::kInt32, GetVIXLAssembler());
}
void IntrinsicLocationsBuilderARM64::VisitLongReverseBytes(HInvoke* invoke) {
CreateIntToIntLocations(allocator_, invoke);
}
void IntrinsicCodeGeneratorARM64::VisitLongReverseBytes(HInvoke* invoke) {
GenReverseBytes(invoke->GetLocations(), DataType::Type::kInt64, GetVIXLAssembler());
}
void IntrinsicLocationsBuilderARM64::VisitShortReverseBytes(HInvoke* invoke) {
CreateIntToIntLocations(allocator_, invoke);
}
void IntrinsicCodeGeneratorARM64::VisitShortReverseBytes(HInvoke* invoke) {
GenReverseBytes(invoke->GetLocations(), DataType::Type::kInt16, GetVIXLAssembler());
}
static void GenNumberOfLeadingZeros(LocationSummary* locations,
DataType::Type type,
MacroAssembler* masm) {
DCHECK(type == DataType::Type::kInt32 || type == DataType::Type::kInt64);
Location in = locations->InAt(0);
Location out = locations->Out();
__ Clz(RegisterFrom(out, type), RegisterFrom(in, type));
}
void IntrinsicLocationsBuilderARM64::VisitIntegerNumberOfLeadingZeros(HInvoke* invoke) {
CreateIntToIntLocations(allocator_, invoke);
}
void IntrinsicCodeGeneratorARM64::VisitIntegerNumberOfLeadingZeros(HInvoke* invoke) {
GenNumberOfLeadingZeros(invoke->GetLocations(), DataType::Type::kInt32, GetVIXLAssembler());
}
void IntrinsicLocationsBuilderARM64::VisitLongNumberOfLeadingZeros(HInvoke* invoke) {
CreateIntToIntLocations(allocator_, invoke);
}
void IntrinsicCodeGeneratorARM64::VisitLongNumberOfLeadingZeros(HInvoke* invoke) {
GenNumberOfLeadingZeros(invoke->GetLocations(), DataType::Type::kInt64, GetVIXLAssembler());
}
static void GenNumberOfTrailingZeros(LocationSummary* locations,
DataType::Type type,
MacroAssembler* masm) {
DCHECK(type == DataType::Type::kInt32 || type == DataType::Type::kInt64);
Location in = locations->InAt(0);
Location out = locations->Out();
__ Rbit(RegisterFrom(out, type), RegisterFrom(in, type));
__ Clz(RegisterFrom(out, type), RegisterFrom(out, type));
}
void IntrinsicLocationsBuilderARM64::VisitIntegerNumberOfTrailingZeros(HInvoke* invoke) {
CreateIntToIntLocations(allocator_, invoke);
}
void IntrinsicCodeGeneratorARM64::VisitIntegerNumberOfTrailingZeros(HInvoke* invoke) {
GenNumberOfTrailingZeros(invoke->GetLocations(), DataType::Type::kInt32, GetVIXLAssembler());
}
void IntrinsicLocationsBuilderARM64::VisitLongNumberOfTrailingZeros(HInvoke* invoke) {
CreateIntToIntLocations(allocator_, invoke);
}
void IntrinsicCodeGeneratorARM64::VisitLongNumberOfTrailingZeros(HInvoke* invoke) {
GenNumberOfTrailingZeros(invoke->GetLocations(), DataType::Type::kInt64, GetVIXLAssembler());
}
static void GenReverse(LocationSummary* locations,
DataType::Type type,
MacroAssembler* masm) {
DCHECK(type == DataType::Type::kInt32 || type == DataType::Type::kInt64);
Location in = locations->InAt(0);
Location out = locations->Out();
__ Rbit(RegisterFrom(out, type), RegisterFrom(in, type));
}
void IntrinsicLocationsBuilderARM64::VisitIntegerReverse(HInvoke* invoke) {
CreateIntToIntLocations(allocator_, invoke);
}
void IntrinsicCodeGeneratorARM64::VisitIntegerReverse(HInvoke* invoke) {
GenReverse(invoke->GetLocations(), DataType::Type::kInt32, GetVIXLAssembler());
}
void IntrinsicLocationsBuilderARM64::VisitLongReverse(HInvoke* invoke) {
CreateIntToIntLocations(allocator_, invoke);
}
void IntrinsicCodeGeneratorARM64::VisitLongReverse(HInvoke* invoke) {
GenReverse(invoke->GetLocations(), DataType::Type::kInt64, GetVIXLAssembler());
}
static void GenBitCount(HInvoke* instr, DataType::Type type, MacroAssembler* masm) {
DCHECK(DataType::IsIntOrLongType(type)) << type;
DCHECK_EQ(instr->GetType(), DataType::Type::kInt32);
DCHECK_EQ(DataType::Kind(instr->InputAt(0)->GetType()), type);
UseScratchRegisterScope temps(masm);
Register src = InputRegisterAt(instr, 0);
Register dst = RegisterFrom(instr->GetLocations()->Out(), type);
VRegister fpr = (type == DataType::Type::kInt64) ? temps.AcquireD() : temps.AcquireS();
__ Fmov(fpr, src);
__ Cnt(fpr.V8B(), fpr.V8B());
__ Addv(fpr.B(), fpr.V8B());
__ Fmov(dst, fpr);
}
void IntrinsicLocationsBuilderARM64::VisitLongBitCount(HInvoke* invoke) {
CreateIntToIntLocations(allocator_, invoke);
}
void IntrinsicCodeGeneratorARM64::VisitLongBitCount(HInvoke* invoke) {
GenBitCount(invoke, DataType::Type::kInt64, GetVIXLAssembler());
}
void IntrinsicLocationsBuilderARM64::VisitIntegerBitCount(HInvoke* invoke) {
CreateIntToIntLocations(allocator_, invoke);
}
void IntrinsicCodeGeneratorARM64::VisitIntegerBitCount(HInvoke* invoke) {
GenBitCount(invoke, DataType::Type::kInt32, GetVIXLAssembler());
}
static void GenHighestOneBit(HInvoke* invoke, DataType::Type type, MacroAssembler* masm) {
DCHECK(type == DataType::Type::kInt32 || type == DataType::Type::kInt64);
UseScratchRegisterScope temps(masm);
Register src = InputRegisterAt(invoke, 0);
Register dst = RegisterFrom(invoke->GetLocations()->Out(), type);
Register temp = (type == DataType::Type::kInt64) ? temps.AcquireX() : temps.AcquireW();
size_t high_bit = (type == DataType::Type::kInt64) ? 63u : 31u;
size_t clz_high_bit = (type == DataType::Type::kInt64) ? 6u : 5u;
__ Clz(temp, src);
__ Mov(dst, UINT64_C(1) << high_bit); // MOV (bitmask immediate)
__ Bic(dst, dst, Operand(temp, LSL, high_bit - clz_high_bit)); // Clear dst if src was 0.
__ Lsr(dst, dst, temp);
}
void IntrinsicLocationsBuilderARM64::VisitIntegerHighestOneBit(HInvoke* invoke) {
CreateIntToIntLocations(allocator_, invoke);
}
void IntrinsicCodeGeneratorARM64::VisitIntegerHighestOneBit(HInvoke* invoke) {
GenHighestOneBit(invoke, DataType::Type::kInt32, GetVIXLAssembler());
}
void IntrinsicLocationsBuilderARM64::VisitLongHighestOneBit(HInvoke* invoke) {
CreateIntToIntLocations(allocator_, invoke);
}
void IntrinsicCodeGeneratorARM64::VisitLongHighestOneBit(HInvoke* invoke) {
GenHighestOneBit(invoke, DataType::Type::kInt64, GetVIXLAssembler());
}
static void GenLowestOneBit(HInvoke* invoke, DataType::Type type, MacroAssembler* masm) {
DCHECK(type == DataType::Type::kInt32 || type == DataType::Type::kInt64);
UseScratchRegisterScope temps(masm);
Register src = InputRegisterAt(invoke, 0);
Register dst = RegisterFrom(invoke->GetLocations()->Out(), type);
Register temp = (type == DataType::Type::kInt64) ? temps.AcquireX() : temps.AcquireW();
__ Neg(temp, src);
__ And(dst, temp, src);
}
void IntrinsicLocationsBuilderARM64::VisitIntegerLowestOneBit(HInvoke* invoke) {
CreateIntToIntLocations(allocator_, invoke);
}
void IntrinsicCodeGeneratorARM64::VisitIntegerLowestOneBit(HInvoke* invoke) {
GenLowestOneBit(invoke, DataType::Type::kInt32, GetVIXLAssembler());
}
void IntrinsicLocationsBuilderARM64::VisitLongLowestOneBit(HInvoke* invoke) {
CreateIntToIntLocations(allocator_, invoke);
}
void IntrinsicCodeGeneratorARM64::VisitLongLowestOneBit(HInvoke* invoke) {
GenLowestOneBit(invoke, DataType::Type::kInt64, GetVIXLAssembler());
}
static void CreateFPToFPLocations(ArenaAllocator* allocator, HInvoke* invoke) {
LocationSummary* locations =
new (allocator) LocationSummary(invoke, LocationSummary::kNoCall, kIntrinsified);
locations->SetInAt(0, Location::RequiresFpuRegister());
locations->SetOut(Location::RequiresFpuRegister(), Location::kNoOutputOverlap);
}
void IntrinsicLocationsBuilderARM64::VisitMathSqrt(HInvoke* invoke) {
CreateFPToFPLocations(allocator_, invoke);
}
void IntrinsicCodeGeneratorARM64::VisitMathSqrt(HInvoke* invoke) {
LocationSummary* locations = invoke->GetLocations();
MacroAssembler* masm = GetVIXLAssembler();
__ Fsqrt(DRegisterFrom(locations->Out()), DRegisterFrom(locations->InAt(0)));
}
void IntrinsicLocationsBuilderARM64::VisitMathCeil(HInvoke* invoke) {
CreateFPToFPLocations(allocator_, invoke);
}
void IntrinsicCodeGeneratorARM64::VisitMathCeil(HInvoke* invoke) {
LocationSummary* locations = invoke->GetLocations();
MacroAssembler* masm = GetVIXLAssembler();
__ Frintp(DRegisterFrom(locations->Out()), DRegisterFrom(locations->InAt(0)));
}
void IntrinsicLocationsBuilderARM64::VisitMathFloor(HInvoke* invoke) {
CreateFPToFPLocations(allocator_, invoke);
}
void IntrinsicCodeGeneratorARM64::VisitMathFloor(HInvoke* invoke) {
LocationSummary* locations = invoke->GetLocations();
MacroAssembler* masm = GetVIXLAssembler();
__ Frintm(DRegisterFrom(locations->Out()), DRegisterFrom(locations->InAt(0)));
}
void IntrinsicLocationsBuilderARM64::VisitMathRint(HInvoke* invoke) {
CreateFPToFPLocations(allocator_, invoke);
}
void IntrinsicCodeGeneratorARM64::VisitMathRint(HInvoke* invoke) {
LocationSummary* locations = invoke->GetLocations();
MacroAssembler* masm = GetVIXLAssembler();
__ Frintn(DRegisterFrom(locations->Out()), DRegisterFrom(locations->InAt(0)));
}
static void CreateFPToIntPlusFPTempLocations(ArenaAllocator* allocator, HInvoke* invoke) {
LocationSummary* locations =
new (allocator) LocationSummary(invoke, LocationSummary::kNoCall, kIntrinsified);
locations->SetInAt(0, Location::RequiresFpuRegister());
locations->SetOut(Location::RequiresRegister());
locations->AddTemp(Location::RequiresFpuRegister());
}
static void GenMathRound(HInvoke* invoke, bool is_double, vixl::aarch64::MacroAssembler* masm) {
// Java 8 API definition for Math.round():
// Return the closest long or int to the argument, with ties rounding to positive infinity.
//
// There is no single instruction in ARMv8 that can support the above definition.
// We choose to use FCVTAS here, because it has closest semantic.
// FCVTAS performs rounding to nearest integer, ties away from zero.
// For most inputs (positive values, zero or NaN), this instruction is enough.
// We only need a few handling code after FCVTAS if the input is negative half value.
//
// The reason why we didn't choose FCVTPS instruction here is that
// although it performs rounding toward positive infinity, it doesn't perform rounding to nearest.
// For example, FCVTPS(-1.9) = -1 and FCVTPS(1.1) = 2.
// If we were using this instruction, for most inputs, more handling code would be needed.
LocationSummary* l = invoke->GetLocations();
VRegister in_reg = is_double ? DRegisterFrom(l->InAt(0)) : SRegisterFrom(l->InAt(0));
VRegister tmp_fp = is_double ? DRegisterFrom(l->GetTemp(0)) : SRegisterFrom(l->GetTemp(0));
Register out_reg = is_double ? XRegisterFrom(l->Out()) : WRegisterFrom(l->Out());
vixl::aarch64::Label done;
// Round to nearest integer, ties away from zero.
__ Fcvtas(out_reg, in_reg);
// For positive values, zero or NaN inputs, rounding is done.
__ Tbz(out_reg, out_reg.GetSizeInBits() - 1, &done);
// Handle input < 0 cases.
// If input is negative but not a tie, previous result (round to nearest) is valid.
// If input is a negative tie, out_reg += 1.
__ Frinta(tmp_fp, in_reg);
__ Fsub(tmp_fp, in_reg, tmp_fp);
__ Fcmp(tmp_fp, 0.5);
__ Cinc(out_reg, out_reg, eq);
__ Bind(&done);
}
void IntrinsicLocationsBuilderARM64::VisitMathRoundDouble(HInvoke* invoke) {
CreateFPToIntPlusFPTempLocations(allocator_, invoke);
}
void IntrinsicCodeGeneratorARM64::VisitMathRoundDouble(HInvoke* invoke) {
GenMathRound(invoke, /* is_double= */ true, GetVIXLAssembler());
}
void IntrinsicLocationsBuilderARM64::VisitMathRoundFloat(HInvoke* invoke) {
CreateFPToIntPlusFPTempLocations(allocator_, invoke);
}
void IntrinsicCodeGeneratorARM64::VisitMathRoundFloat(HInvoke* invoke) {
GenMathRound(invoke, /* is_double= */ false, GetVIXLAssembler());
}
void IntrinsicLocationsBuilderARM64::VisitMemoryPeekByte(HInvoke* invoke) {
CreateIntToIntLocations(allocator_, invoke);
}
void IntrinsicCodeGeneratorARM64::VisitMemoryPeekByte(HInvoke* invoke) {
MacroAssembler* masm = GetVIXLAssembler();
__ Ldrsb(WRegisterFrom(invoke->GetLocations()->Out()),
AbsoluteHeapOperandFrom(invoke->GetLocations()->InAt(0), 0));
}
void IntrinsicLocationsBuilderARM64::VisitMemoryPeekIntNative(HInvoke* invoke) {
CreateIntToIntLocations(allocator_, invoke);
}
void IntrinsicCodeGeneratorARM64::VisitMemoryPeekIntNative(HInvoke* invoke) {
MacroAssembler* masm = GetVIXLAssembler();
__ Ldr(WRegisterFrom(invoke->GetLocations()->Out()),
AbsoluteHeapOperandFrom(invoke->GetLocations()->InAt(0), 0));
}
void IntrinsicLocationsBuilderARM64::VisitMemoryPeekLongNative(HInvoke* invoke) {
CreateIntToIntLocations(allocator_, invoke);
}
void IntrinsicCodeGeneratorARM64::VisitMemoryPeekLongNative(HInvoke* invoke) {
MacroAssembler* masm = GetVIXLAssembler();
__ Ldr(XRegisterFrom(invoke->GetLocations()->Out()),
AbsoluteHeapOperandFrom(invoke->GetLocations()->InAt(0), 0));
}
void IntrinsicLocationsBuilderARM64::VisitMemoryPeekShortNative(HInvoke* invoke) {
CreateIntToIntLocations(allocator_, invoke);
}
void IntrinsicCodeGeneratorARM64::VisitMemoryPeekShortNative(HInvoke* invoke) {
MacroAssembler* masm = GetVIXLAssembler();
__ Ldrsh(WRegisterFrom(invoke->GetLocations()->Out()),
AbsoluteHeapOperandFrom(invoke->GetLocations()->InAt(0), 0));
}
static void CreateIntIntToVoidLocations(ArenaAllocator* allocator, HInvoke* invoke) {
LocationSummary* locations =
new (allocator) LocationSummary(invoke, LocationSummary::kNoCall, kIntrinsified);
locations->SetInAt(0, Location::RequiresRegister());
locations->SetInAt(1, Location::RequiresRegister());
}
void IntrinsicLocationsBuilderARM64::VisitMemoryPokeByte(HInvoke* invoke) {
CreateIntIntToVoidLocations(allocator_, invoke);
}
void IntrinsicCodeGeneratorARM64::VisitMemoryPokeByte(HInvoke* invoke) {
MacroAssembler* masm = GetVIXLAssembler();
__ Strb(WRegisterFrom(invoke->GetLocations()->InAt(1)),
AbsoluteHeapOperandFrom(invoke->GetLocations()->InAt(0), 0));
}
void IntrinsicLocationsBuilderARM64::VisitMemoryPokeIntNative(HInvoke* invoke) {
CreateIntIntToVoidLocations(allocator_, invoke);
}
void IntrinsicCodeGeneratorARM64::VisitMemoryPokeIntNative(HInvoke* invoke) {
MacroAssembler* masm = GetVIXLAssembler();
__ Str(WRegisterFrom(invoke->GetLocations()->InAt(1)),
AbsoluteHeapOperandFrom(invoke->GetLocations()->InAt(0), 0));
}
void IntrinsicLocationsBuilderARM64::VisitMemoryPokeLongNative(HInvoke* invoke) {
CreateIntIntToVoidLocations(allocator_, invoke);
}
void IntrinsicCodeGeneratorARM64::VisitMemoryPokeLongNative(HInvoke* invoke) {
MacroAssembler* masm = GetVIXLAssembler();
__ Str(XRegisterFrom(invoke->GetLocations()->InAt(1)),
AbsoluteHeapOperandFrom(invoke->GetLocations()->InAt(0), 0));
}
void IntrinsicLocationsBuilderARM64::VisitMemoryPokeShortNative(HInvoke* invoke) {
CreateIntIntToVoidLocations(allocator_, invoke);
}
void IntrinsicCodeGeneratorARM64::VisitMemoryPokeShortNative(HInvoke* invoke) {
MacroAssembler* masm = GetVIXLAssembler();
__ Strh(WRegisterFrom(invoke->GetLocations()->InAt(1)),
AbsoluteHeapOperandFrom(invoke->GetLocations()->InAt(0), 0));
}
void IntrinsicLocationsBuilderARM64::VisitThreadCurrentThread(HInvoke* invoke) {
LocationSummary* locations =
new (allocator_) LocationSummary(invoke, LocationSummary::kNoCall, kIntrinsified);
locations->SetOut(Location::RequiresRegister());
}
void IntrinsicCodeGeneratorARM64::VisitThreadCurrentThread(HInvoke* invoke) {
codegen_->Load(DataType::Type::kReference, WRegisterFrom(invoke->GetLocations()->Out()),
MemOperand(tr, Thread::PeerOffset<kArm64PointerSize>().Int32Value()));
}
static void GenUnsafeGet(HInvoke* invoke,
DataType::Type type,
bool is_volatile,
CodeGeneratorARM64* codegen) {
LocationSummary* locations = invoke->GetLocations();
DCHECK((type == DataType::Type::kInt32) ||
(type == DataType::Type::kInt64) ||
(type == DataType::Type::kReference));
Location base_loc = locations->InAt(1);
Register base = WRegisterFrom(base_loc); // Object pointer.
Location offset_loc = locations->InAt(2);
Register offset = XRegisterFrom(offset_loc); // Long offset.
Location trg_loc = locations->Out();
Register trg = RegisterFrom(trg_loc, type);
if (type == DataType::Type::kReference && kEmitCompilerReadBarrier && kUseBakerReadBarrier) {
// UnsafeGetObject/UnsafeGetObjectVolatile with Baker's read barrier case.
Register temp = WRegisterFrom(locations->GetTemp(0));
MacroAssembler* masm = codegen->GetVIXLAssembler();
// Piggy-back on the field load path using introspection for the Baker read barrier.
__ Add(temp, base, offset.W()); // Offset should not exceed 32 bits.
codegen->GenerateFieldLoadWithBakerReadBarrier(invoke,
trg_loc,
base,
MemOperand(temp.X()),
/* needs_null_check= */ false,
is_volatile);
} else {
// Other cases.
MemOperand mem_op(base.X(), offset);
if (is_volatile) {
codegen->LoadAcquire(invoke, type, trg, mem_op, /* needs_null_check= */ true);
} else {
codegen->Load(type, trg, mem_op);
}
if (type == DataType::Type::kReference) {
DCHECK(trg.IsW());
codegen->MaybeGenerateReadBarrierSlow(invoke, trg_loc, trg_loc, base_loc, 0u, offset_loc);
}
}
}
static void CreateIntIntIntToIntLocations(ArenaAllocator* allocator, HInvoke* invoke) {
bool can_call = kEmitCompilerReadBarrier &&
(invoke->GetIntrinsic() == Intrinsics::kUnsafeGetObject ||
invoke->GetIntrinsic() == Intrinsics::kUnsafeGetObjectVolatile);
LocationSummary* locations =
new (allocator) LocationSummary(invoke,
can_call
? LocationSummary::kCallOnSlowPath
: LocationSummary::kNoCall,
kIntrinsified);
if (can_call && kUseBakerReadBarrier) {
locations->SetCustomSlowPathCallerSaves(RegisterSet::Empty()); // No caller-save registers.
// We need a temporary register for the read barrier load in order to use
// CodeGeneratorARM64::GenerateFieldLoadWithBakerReadBarrier().
locations->AddTemp(FixedTempLocation());
}
locations->SetInAt(0, Location::NoLocation()); // Unused receiver.
locations->SetInAt(1, Location::RequiresRegister());
locations->SetInAt(2, Location::RequiresRegister());
locations->SetOut(Location::RequiresRegister(),
(can_call ? Location::kOutputOverlap : Location::kNoOutputOverlap));
}
void IntrinsicLocationsBuilderARM64::VisitUnsafeGet(HInvoke* invoke) {
CreateIntIntIntToIntLocations(allocator_, invoke);
}
void IntrinsicLocationsBuilderARM64::VisitUnsafeGetVolatile(HInvoke* invoke) {
CreateIntIntIntToIntLocations(allocator_, invoke);
}
void IntrinsicLocationsBuilderARM64::VisitUnsafeGetLong(HInvoke* invoke) {
CreateIntIntIntToIntLocations(allocator_, invoke);
}
void IntrinsicLocationsBuilderARM64::VisitUnsafeGetLongVolatile(HInvoke* invoke) {
CreateIntIntIntToIntLocations(allocator_, invoke);
}
void IntrinsicLocationsBuilderARM64::VisitUnsafeGetObject(HInvoke* invoke) {
CreateIntIntIntToIntLocations(allocator_, invoke);
}
void IntrinsicLocationsBuilderARM64::VisitUnsafeGetObjectVolatile(HInvoke* invoke) {
CreateIntIntIntToIntLocations(allocator_, invoke);
}
void IntrinsicCodeGeneratorARM64::VisitUnsafeGet(HInvoke* invoke) {
GenUnsafeGet(invoke, DataType::Type::kInt32, /* is_volatile= */ false, codegen_);
}
void IntrinsicCodeGeneratorARM64::VisitUnsafeGetVolatile(HInvoke* invoke) {
GenUnsafeGet(invoke, DataType::Type::kInt32, /* is_volatile= */ true, codegen_);
}
void IntrinsicCodeGeneratorARM64::VisitUnsafeGetLong(HInvoke* invoke) {
GenUnsafeGet(invoke, DataType::Type::kInt64, /* is_volatile= */ false, codegen_);
}
void IntrinsicCodeGeneratorARM64::VisitUnsafeGetLongVolatile(HInvoke* invoke) {
GenUnsafeGet(invoke, DataType::Type::kInt64, /* is_volatile= */ true, codegen_);
}
void IntrinsicCodeGeneratorARM64::VisitUnsafeGetObject(HInvoke* invoke) {
GenUnsafeGet(invoke, DataType::Type::kReference, /* is_volatile= */ false, codegen_);
}
void IntrinsicCodeGeneratorARM64::VisitUnsafeGetObjectVolatile(HInvoke* invoke) {
GenUnsafeGet(invoke, DataType::Type::kReference, /* is_volatile= */ true, codegen_);
}
static void CreateIntIntIntIntToVoid(ArenaAllocator* allocator, HInvoke* invoke) {
LocationSummary* locations =
new (allocator) LocationSummary(invoke, LocationSummary::kNoCall, kIntrinsified);
locations->SetInAt(0, Location::NoLocation()); // Unused receiver.
locations->SetInAt(1, Location::RequiresRegister());
locations->SetInAt(2, Location::RequiresRegister());
locations->SetInAt(3, Location::RequiresRegister());
}
void IntrinsicLocationsBuilderARM64::VisitUnsafePut(HInvoke* invoke) {
CreateIntIntIntIntToVoid(allocator_, invoke);
}
void IntrinsicLocationsBuilderARM64::VisitUnsafePutOrdered(HInvoke* invoke) {
CreateIntIntIntIntToVoid(allocator_, invoke);
}
void IntrinsicLocationsBuilderARM64::VisitUnsafePutVolatile(HInvoke* invoke) {
CreateIntIntIntIntToVoid(allocator_, invoke);
}
void IntrinsicLocationsBuilderARM64::VisitUnsafePutObject(HInvoke* invoke) {
CreateIntIntIntIntToVoid(allocator_, invoke);
}
void IntrinsicLocationsBuilderARM64::VisitUnsafePutObjectOrdered(HInvoke* invoke) {
CreateIntIntIntIntToVoid(allocator_, invoke);
}
void IntrinsicLocationsBuilderARM64::VisitUnsafePutObjectVolatile(HInvoke* invoke) {
CreateIntIntIntIntToVoid(allocator_, invoke);
}
void IntrinsicLocationsBuilderARM64::VisitUnsafePutLong(HInvoke* invoke) {
CreateIntIntIntIntToVoid(allocator_, invoke);
}
void IntrinsicLocationsBuilderARM64::VisitUnsafePutLongOrdered(HInvoke* invoke) {
CreateIntIntIntIntToVoid(allocator_, invoke);
}
void IntrinsicLocationsBuilderARM64::VisitUnsafePutLongVolatile(HInvoke* invoke) {
CreateIntIntIntIntToVoid(allocator_, invoke);
}
static void GenUnsafePut(HInvoke* invoke,
DataType::Type type,
bool is_volatile,
bool is_ordered,
CodeGeneratorARM64* codegen) {
LocationSummary* locations = invoke->GetLocations();
MacroAssembler* masm = codegen->GetVIXLAssembler();
Register base = WRegisterFrom(locations->InAt(1)); // Object pointer.
Register offset = XRegisterFrom(locations->InAt(2)); // Long offset.
Register value = RegisterFrom(locations->InAt(3), type);
Register source = value;
MemOperand mem_op(base.X(), offset);
{
// We use a block to end the scratch scope before the write barrier, thus
// freeing the temporary registers so they can be used in `MarkGCCard`.
UseScratchRegisterScope temps(masm);
if (kPoisonHeapReferences && type == DataType::Type::kReference) {
DCHECK(value.IsW());
Register temp = temps.AcquireW();
__ Mov(temp.W(), value.W());
codegen->GetAssembler()->PoisonHeapReference(temp.W());
source = temp;
}
if (is_volatile || is_ordered) {
codegen->StoreRelease(invoke, type, source, mem_op, /* needs_null_check= */ false);
} else {
codegen->Store(type, source, mem_op);
}
}
if (type == DataType::Type::kReference) {
bool value_can_be_null = true; // TODO: Worth finding out this information?
codegen->MarkGCCard(base, value, value_can_be_null);
}
}
void IntrinsicCodeGeneratorARM64::VisitUnsafePut(HInvoke* invoke) {
GenUnsafePut(invoke,
DataType::Type::kInt32,
/* is_volatile= */ false,
/* is_ordered= */ false,
codegen_);
}
void IntrinsicCodeGeneratorARM64::VisitUnsafePutOrdered(HInvoke* invoke) {
GenUnsafePut(invoke,
DataType::Type::kInt32,
/* is_volatile= */ false,
/* is_ordered= */ true,
codegen_);
}
void IntrinsicCodeGeneratorARM64::VisitUnsafePutVolatile(HInvoke* invoke) {
GenUnsafePut(invoke,
DataType::Type::kInt32,
/* is_volatile= */ true,
/* is_ordered= */ false,
codegen_);
}
void IntrinsicCodeGeneratorARM64::VisitUnsafePutObject(HInvoke* invoke) {
GenUnsafePut(invoke,
DataType::Type::kReference,
/* is_volatile= */ false,
/* is_ordered= */ false,
codegen_);
}
void IntrinsicCodeGeneratorARM64::VisitUnsafePutObjectOrdered(HInvoke* invoke) {
GenUnsafePut(invoke,
DataType::Type::kReference,
/* is_volatile= */ false,
/* is_ordered= */ true,
codegen_);
}
void IntrinsicCodeGeneratorARM64::VisitUnsafePutObjectVolatile(HInvoke* invoke) {
GenUnsafePut(invoke,
DataType::Type::kReference,
/* is_volatile= */ true,
/* is_ordered= */ false,
codegen_);
}
void IntrinsicCodeGeneratorARM64::VisitUnsafePutLong(HInvoke* invoke) {
GenUnsafePut(invoke,
DataType::Type::kInt64,
/* is_volatile= */ false,
/* is_ordered= */ false,
codegen_);
}
void IntrinsicCodeGeneratorARM64::VisitUnsafePutLongOrdered(HInvoke* invoke) {
GenUnsafePut(invoke,
DataType::Type::kInt64,
/* is_volatile= */ false,
/* is_ordered= */ true,
codegen_);
}
void IntrinsicCodeGeneratorARM64::VisitUnsafePutLongVolatile(HInvoke* invoke) {
GenUnsafePut(invoke,
DataType::Type::kInt64,
/* is_volatile= */ true,
/* is_ordered= */ false,
codegen_);
}
static void CreateUnsafeCASLocations(ArenaAllocator* allocator, HInvoke* invoke) {
bool can_call = kEmitCompilerReadBarrier &&
(invoke->GetIntrinsic() == Intrinsics::kUnsafeCASObject);
LocationSummary* locations =
new (allocator) LocationSummary(invoke,
can_call
? LocationSummary::kCallOnSlowPath
: LocationSummary::kNoCall,
kIntrinsified);
if (can_call && kUseBakerReadBarrier) {
locations->SetCustomSlowPathCallerSaves(RegisterSet::Empty()); // No caller-save registers.
}
locations->SetInAt(0, Location::NoLocation()); // Unused receiver.
locations->SetInAt(1, Location::RequiresRegister());
locations->SetInAt(2, Location::RequiresRegister());
locations->SetInAt(3, Location::RequiresRegister());
locations->SetInAt(4, Location::RequiresRegister());
locations->SetOut(Location::RequiresRegister(), Location::kNoOutputOverlap);
}
static void EmitLoadExclusive(CodeGeneratorARM64* codegen,
DataType::Type type,
Register ptr,
Register old_value,
bool use_load_acquire) {
Arm64Assembler* assembler = codegen->GetAssembler();
MacroAssembler* masm = assembler->GetVIXLAssembler();
switch (type) {
case DataType::Type::kBool:
case DataType::Type::kUint8:
case DataType::Type::kInt8:
if (use_load_acquire) {
__ Ldaxrb(old_value, MemOperand(ptr));
} else {
__ Ldxrb(old_value, MemOperand(ptr));
}
break;
case DataType::Type::kUint16:
case DataType::Type::kInt16:
if (use_load_acquire) {
__ Ldaxrh(old_value, MemOperand(ptr));
} else {
__ Ldxrh(old_value, MemOperand(ptr));
}
break;
case DataType::Type::kInt32:
case DataType::Type::kInt64:
case DataType::Type::kReference:
if (use_load_acquire) {
__ Ldaxr(old_value, MemOperand(ptr));
} else {
__ Ldxr(old_value, MemOperand(ptr));
}
break;
default:
LOG(FATAL) << "Unexpected type: " << type;
UNREACHABLE();
}
switch (type) {
case DataType::Type::kInt8:
__ Sxtb(old_value, old_value);
break;
case DataType::Type::kInt16:
__ Sxth(old_value, old_value);
break;
case DataType::Type::kReference:
assembler->MaybeUnpoisonHeapReference(old_value);
break;
default:
break;
}
}
static void EmitStoreExclusive(CodeGeneratorARM64* codegen,
DataType::Type type,
Register ptr,
Register store_result,
Register new_value,
bool use_store_release) {
Arm64Assembler* assembler = codegen->GetAssembler();
MacroAssembler* masm = assembler->GetVIXLAssembler();
if (type == DataType::Type::kReference) {
assembler->MaybePoisonHeapReference(new_value);
}
switch (type) {
case DataType::Type::kBool:
case DataType::Type::kUint8:
case DataType::Type::kInt8:
if (use_store_release) {
__ Stlxrb(store_result, new_value, MemOperand(ptr));
} else {
__ Stxrb(store_result, new_value, MemOperand(ptr));
}
break;
case DataType::Type::kUint16:
case DataType::Type::kInt16:
if (use_store_release) {
__ Stlxrh(store_result, new_value, MemOperand(ptr));
} else {
__ Stxrh(store_result, new_value, MemOperand(ptr));
}
break;
case DataType::Type::kInt32:
case DataType::Type::kInt64:
case DataType::Type::kReference:
if (use_store_release) {
__ Stlxr(store_result, new_value, MemOperand(ptr));
} else {
__ Stxr(store_result, new_value, MemOperand(ptr));
}
break;
default:
LOG(FATAL) << "Unexpected type: " << type;
UNREACHABLE();
}
if (type == DataType::Type::kReference) {
assembler->MaybeUnpoisonHeapReference(new_value);
}
}
static void GenerateCompareAndSet(CodeGeneratorARM64* codegen,
DataType::Type type,
std::memory_order order,
bool strong,
vixl::aarch64::Label* cmp_failure,
Register ptr,
Register new_value,
Register old_value,
Register store_result,
Register expected,
Register expected2 = Register()) {
// The `expected2` is valid only for reference slow path and represents the unmarked old value
// from the main path attempt to emit CAS when the marked old value matched `expected`.
DCHECK(type == DataType::Type::kReference || !expected2.IsValid());
DCHECK(ptr.IsX());
DCHECK_EQ(new_value.IsX(), type == DataType::Type::kInt64);
DCHECK_EQ(old_value.IsX(), type == DataType::Type::kInt64);
DCHECK(store_result.IsW());
DCHECK_EQ(expected.IsX(), type == DataType::Type::kInt64);
DCHECK(!expected2.IsValid() || expected2.IsW());
Arm64Assembler* assembler = codegen->GetAssembler();
MacroAssembler* masm = assembler->GetVIXLAssembler();
bool use_load_acquire =
(order == std::memory_order_acquire) || (order == std::memory_order_seq_cst);
bool use_store_release =
(order == std::memory_order_release) || (order == std::memory_order_seq_cst);
DCHECK(use_load_acquire || use_store_release || order == std::memory_order_relaxed);
// repeat: {
// old_value = [ptr]; // Load exclusive.
// if (old_value != expected && old_value != expected2) goto cmp_failure;
// store_result = failed([ptr] <- new_value); // Store exclusive.
// }
// if (strong) {
// if (store_result) goto repeat; // Repeat until compare fails or store exclusive succeeds.
// } else {
// store_result = store_result ^ 1; // Report success as 1, failure as 0.
// }
//
// Flag Z indicates whether `old_value == expected || old_value == expected2`.
// (Is `expected2` is not valid, the `old_value == expected2` part is not emitted.)
vixl::aarch64::Label loop_head;
if (strong) {
__ Bind(&loop_head);
}
EmitLoadExclusive(codegen, type, ptr, old_value, use_load_acquire);
__ Cmp(old_value, expected);
if (expected2.IsValid()) {
__ Ccmp(old_value, expected2, ZFlag, ne);
}
// If the comparison failed, the Z flag is cleared as we branch to the `cmp_failure` label.
// If the comparison succeeded, the Z flag is set and remains set after the end of the
// code emitted here, unless we retry the whole operation.
__ B(cmp_failure, ne);
EmitStoreExclusive(codegen, type, ptr, store_result, new_value, use_store_release);
if (strong) {
__ Cbnz(store_result, &loop_head);
} else {
// Flip the `store_result` register to indicate success by 1 and failure by 0.
__ Eor(store_result, store_result, 1);
}
}
class ReadBarrierCasSlowPathARM64 : public SlowPathCodeARM64 {
public:
ReadBarrierCasSlowPathARM64(HInvoke* invoke,
std::memory_order order,
bool strong,
Register base,
Register offset,
Register expected,
Register new_value,
Register old_value,
Register old_value_temp,
Register store_result,
bool update_old_value,
CodeGeneratorARM64* arm64_codegen)
: SlowPathCodeARM64(invoke),
order_(order),
strong_(strong),
base_(base),
offset_(offset),
expected_(expected),
new_value_(new_value),
old_value_(old_value),
old_value_temp_(old_value_temp),
store_result_(store_result),
update_old_value_(update_old_value),
mark_old_value_slow_path_(nullptr),
update_old_value_slow_path_(nullptr) {
if (!kUseBakerReadBarrier) {
// We need to add the slow path now, it is too late when emitting slow path code.
mark_old_value_slow_path_ = arm64_codegen->AddReadBarrierSlowPath(
invoke,
Location::RegisterLocation(old_value_temp.GetCode()),
Location::RegisterLocation(old_value.GetCode()),
Location::RegisterLocation(base.GetCode()),
/*offset=*/ 0u,
/*index=*/ Location::RegisterLocation(offset.GetCode()));
if (update_old_value_) {
update_old_value_slow_path_ = arm64_codegen->AddReadBarrierSlowPath(
invoke,
Location::RegisterLocation(old_value.GetCode()),
Location::RegisterLocation(old_value_temp.GetCode()),
Location::RegisterLocation(base.GetCode()),
/*offset=*/ 0u,
/*index=*/ Location::RegisterLocation(offset.GetCode()));
}
}
}
const char* GetDescription() const override { return "ReadBarrierCasSlowPathARM64"; }
void EmitNativeCode(CodeGenerator* codegen) override {
CodeGeneratorARM64* arm64_codegen = down_cast<CodeGeneratorARM64*>(codegen);
Arm64Assembler* assembler = arm64_codegen->GetAssembler();
MacroAssembler* masm = assembler->GetVIXLAssembler();
__ Bind(GetEntryLabel());
// Mark the `old_value_` from the main path and compare with `expected_`.
if (kUseBakerReadBarrier) {
DCHECK(mark_old_value_slow_path_ == nullptr);
arm64_codegen->GenerateIntrinsicCasMoveWithBakerReadBarrier(old_value_temp_, old_value_);
} else {
DCHECK(mark_old_value_slow_path_ != nullptr);
__ B(mark_old_value_slow_path_->GetEntryLabel());
__ Bind(mark_old_value_slow_path_->GetExitLabel());
}
__ Cmp(old_value_temp_, expected_);
if (update_old_value_) {
// Update the old value if we're going to return from the slow path.
__ Csel(old_value_, old_value_temp_, old_value_, ne);
}
__ B(GetExitLabel(), ne); // If taken, Z=false indicates failure.
// The `old_value` we have read did not match `expected` (which is always a to-space
// reference) but after the read barrier the marked to-space value matched, so the
// `old_value` must be a from-space reference to the same object. Do the same CAS loop
// as the main path but check for both `expected` and the unmarked old value
// representing the to-space and from-space references for the same object.
UseScratchRegisterScope temps(masm);
DCHECK(!store_result_.IsValid() || !temps.IsAvailable(store_result_));
Register tmp_ptr = temps.AcquireX();
Register store_result = store_result_.IsValid() ? store_result_ : temps.AcquireW();
// Recalculate the `tmp_ptr` from main path clobbered by the read barrier above.
__ Add(tmp_ptr, base_.X(), Operand(offset_));
vixl::aarch64::Label mark_old_value;
GenerateCompareAndSet(arm64_codegen,
DataType::Type::kReference,
order_,
strong_,
/*cmp_failure=*/ update_old_value_ ? &mark_old_value : GetExitLabel(),
tmp_ptr,
new_value_,
/*old_value=*/ old_value_temp_,
store_result,
expected_,
/*expected2=*/ old_value_);
if (update_old_value_) {
// To reach this point, the `old_value_temp_` must be either a from-space or a to-space
// reference of the `expected_` object. Update the `old_value_` to the to-space reference.
__ Mov(old_value_, expected_);
}
// Z=true from the CMP+CCMP in GenerateCompareAndSet() above indicates comparison success.
// For strong CAS, that's the overall success. For weak CAS, the code also needs
// to check the `store_result` after returning from the slow path.
__ B(GetExitLabel());
if (update_old_value_) {
__ Bind(&mark_old_value);
if (kUseBakerReadBarrier) {
DCHECK(update_old_value_slow_path_ == nullptr);
arm64_codegen->GenerateIntrinsicCasMoveWithBakerReadBarrier(old_value_, old_value_temp_);
} else {
// Note: We could redirect the `failure` above directly to the entry label and bind
// the exit label in the main path, but the main path would need to access the
// `update_old_value_slow_path_`. To keep the code simple, keep the extra jumps.
DCHECK(update_old_value_slow_path_ != nullptr);
__ B(update_old_value_slow_path_->GetEntryLabel());
__ Bind(update_old_value_slow_path_->GetExitLabel());
}
__ B(GetExitLabel());
}
}
private:
std::memory_order order_;
bool strong_;
Register base_;
Register offset_;
Register expected_;
Register new_value_;
Register old_value_;
Register old_value_temp_;
Register store_result_;
bool update_old_value_;
SlowPathCodeARM64* mark_old_value_slow_path_;
SlowPathCodeARM64* update_old_value_slow_path_;
};
static void GenUnsafeCas(HInvoke* invoke, DataType::Type type, CodeGeneratorARM64* codegen) {
MacroAssembler* masm = codegen->GetVIXLAssembler();
LocationSummary* locations = invoke->GetLocations();
Register out = WRegisterFrom(locations->Out()); // Boolean result.
Register base = WRegisterFrom(locations->InAt(1)); // Object pointer.
Register offset = XRegisterFrom(locations->InAt(2)); // Long offset.
Register expected = RegisterFrom(locations->InAt(3), type); // Expected.
Register new_value = RegisterFrom(locations->InAt(4), type); // New value.
// This needs to be before the temp registers, as MarkGCCard also uses VIXL temps.
if (type == DataType::Type::kReference) {
// Mark card for object assuming new value is stored.
bool new_value_can_be_null = true; // TODO: Worth finding out this information?
codegen->MarkGCCard(base, new_value, new_value_can_be_null);
}
UseScratchRegisterScope temps(masm);
Register tmp_ptr = temps.AcquireX(); // Pointer to actual memory.
Register old_value; // Value in memory.
vixl::aarch64::Label exit_loop_label;
vixl::aarch64::Label* exit_loop = &exit_loop_label;
vixl::aarch64::Label* cmp_failure = &exit_loop_label;
if (kEmitCompilerReadBarrier && type == DataType::Type::kReference) {
// We need to store the `old_value` in a non-scratch register to make sure
// the read barrier in the slow path does not clobber it.
old_value = WRegisterFrom(locations->GetTemp(0)); // The old value from main path.
// The `old_value_temp` is used first for the marked `old_value` and then for the unmarked
// reloaded old value for subsequent CAS in the slow path. It cannot be a scratch register.
Register old_value_temp = WRegisterFrom(locations->GetTemp(1));
ReadBarrierCasSlowPathARM64* slow_path =
new (codegen->GetScopedAllocator()) ReadBarrierCasSlowPathARM64(
invoke,
std::memory_order_seq_cst,
/*strong=*/ true,
base,
offset,
expected,
new_value,
old_value,
old_value_temp,
/*store_result=*/ Register(), // Use a scratch register.
/*update_old_value=*/ false,
codegen);
codegen->AddSlowPath(slow_path);
exit_loop = slow_path->GetExitLabel();
cmp_failure = slow_path->GetEntryLabel();
} else {
old_value = temps.AcquireSameSizeAs(new_value);
}
__ Add(tmp_ptr, base.X(), Operand(offset));
GenerateCompareAndSet(codegen,
type,
std::memory_order_seq_cst,
/*strong=*/ true,
cmp_failure,
tmp_ptr,
new_value,
old_value,
/*store_result=*/ old_value.W(), // Reuse `old_value` for ST*XR* result.
expected);
__ Bind(exit_loop);
__ Cset(out, eq);
}
void IntrinsicLocationsBuilderARM64::VisitUnsafeCASInt(HInvoke* invoke) {
CreateUnsafeCASLocations(allocator_, invoke);
}
void IntrinsicLocationsBuilderARM64::VisitUnsafeCASLong(HInvoke* invoke) {
CreateUnsafeCASLocations(allocator_, invoke);
}
void IntrinsicLocationsBuilderARM64::VisitUnsafeCASObject(HInvoke* invoke) {
// The only read barrier implementation supporting the
// UnsafeCASObject intrinsic is the Baker-style read barriers. b/173104084
if (kEmitCompilerReadBarrier && !kUseBakerReadBarrier) {
return;
}
CreateUnsafeCASLocations(allocator_, invoke);
if (kEmitCompilerReadBarrier) {
// We need two non-scratch temporary registers for read barrier.
LocationSummary* locations = invoke->GetLocations();
if (kUseBakerReadBarrier) {
locations->AddTemp(Location::RequiresRegister());
locations->AddTemp(Location::RequiresRegister());
} else {
// To preserve the old value across the non-Baker read barrier
// slow path, use a fixed callee-save register.
constexpr int first_callee_save = CTZ(kArm64CalleeSaveRefSpills);
locations->AddTemp(Location::RegisterLocation(first_callee_save));
// To reduce the number of moves, request x0 as the second temporary.
DCHECK(InvokeRuntimeCallingConvention().GetReturnLocation(DataType::Type::kReference).Equals(
Location::RegisterLocation(x0.GetCode())));
locations->AddTemp(Location::RegisterLocation(x0.GetCode()));
}
}
}
void IntrinsicCodeGeneratorARM64::VisitUnsafeCASInt(HInvoke* invoke) {
GenUnsafeCas(invoke, DataType::Type::kInt32, codegen_);
}
void IntrinsicCodeGeneratorARM64::VisitUnsafeCASLong(HInvoke* invoke) {
GenUnsafeCas(invoke, DataType::Type::kInt64, codegen_);
}
void IntrinsicCodeGeneratorARM64::VisitUnsafeCASObject(HInvoke* invoke) {
GenUnsafeCas(invoke, DataType::Type::kReference, codegen_);
}
enum class GetAndUpdateOp {
kSet,
kAdd,
kAddWithByteSwap,
kAnd,
kOr,
kXor
};
static void GenerateGetAndUpdate(CodeGeneratorARM64* codegen,
GetAndUpdateOp get_and_update_op,
DataType::Type load_store_type,
std::memory_order order,
Register ptr,
CPURegister arg,
CPURegister old_value) {
MacroAssembler* masm = codegen->GetVIXLAssembler();
UseScratchRegisterScope temps(masm);
Register store_result = temps.AcquireW();
DCHECK_EQ(old_value.GetSizeInBits(), arg.GetSizeInBits());
Register old_value_reg;
Register new_value;
switch (get_and_update_op) {
case GetAndUpdateOp::kSet:
old_value_reg = old_value.IsX() ? old_value.X() : old_value.W();
new_value = arg.IsX() ? arg.X() : arg.W();
break;
case GetAndUpdateOp::kAddWithByteSwap:
case GetAndUpdateOp::kAdd:
if (arg.IsVRegister()) {
old_value_reg = arg.IsD() ? temps.AcquireX() : temps.AcquireW();
new_value = old_value_reg; // Use the same temporary.
break;
}
FALLTHROUGH_INTENDED;
case GetAndUpdateOp::kAnd:
case GetAndUpdateOp::kOr:
case GetAndUpdateOp::kXor:
old_value_reg = old_value.IsX() ? old_value.X() : old_value.W();
new_value = old_value.IsX() ? temps.AcquireX() : temps.AcquireW();
break;
}
bool use_load_acquire =
(order == std::memory_order_acquire) || (order == std::memory_order_seq_cst);
bool use_store_release =
(order == std::memory_order_release) || (order == std::memory_order_seq_cst);
DCHECK(use_load_acquire || use_store_release);
vixl::aarch64::Label loop_label;
__ Bind(&loop_label);
EmitLoadExclusive(codegen, load_store_type, ptr, old_value_reg, use_load_acquire);
switch (get_and_update_op) {
case GetAndUpdateOp::kSet:
break;
case GetAndUpdateOp::kAddWithByteSwap:
// To avoid unnecessary sign extension before REV16, the caller must specify `kUint16`
// instead of `kInt16` and do the sign-extension explicitly afterwards.
DCHECK_NE(load_store_type, DataType::Type::kInt16);
GenerateReverseBytes(masm, load_store_type, old_value_reg, old_value_reg);
FALLTHROUGH_INTENDED;
case GetAndUpdateOp::kAdd:
if (arg.IsVRegister()) {
VRegister old_value_vreg = old_value.IsD() ? old_value.D() : old_value.S();
VRegister sum = temps.AcquireSameSizeAs(old_value_vreg);
__ Fmov(old_value_vreg, old_value_reg);
__ Fadd(sum, old_value_vreg, arg.IsD() ? arg.D() : arg.S());
__ Fmov(new_value, sum);
} else {
__ Add(new_value, old_value_reg, arg.IsX() ? arg.X() : arg.W());
}
if (get_and_update_op == GetAndUpdateOp::kAddWithByteSwap) {
GenerateReverseBytes(masm, load_store_type, new_value, new_value);
}
break;
case GetAndUpdateOp::kAnd:
__ And(new_value, old_value_reg, arg.IsX() ? arg.X() : arg.W());
break;
case GetAndUpdateOp::kOr:
__ Orr(new_value, old_value_reg, arg.IsX() ? arg.X() : arg.W());
break;
case GetAndUpdateOp::kXor:
__ Eor(new_value, old_value_reg, arg.IsX() ? arg.X() : arg.W());
break;
}
EmitStoreExclusive(codegen, load_store_type, ptr, store_result, new_value, use_store_release);
__ Cbnz(store_result, &loop_label);
}
void IntrinsicLocationsBuilderARM64::VisitStringCompareTo(HInvoke* invoke) {
LocationSummary* locations =
new (allocator_) LocationSummary(invoke,
invoke->InputAt(1)->CanBeNull()
? LocationSummary::kCallOnSlowPath
: LocationSummary::kNoCall,
kIntrinsified);
locations->SetInAt(0, Location::RequiresRegister());
locations->SetInAt(1, Location::RequiresRegister());
locations->AddTemp(Location::RequiresRegister());
locations->AddTemp(Location::RequiresRegister());
locations->AddTemp(Location::RequiresRegister());
// Need temporary registers for String compression's feature.
if (mirror::kUseStringCompression) {
locations->AddTemp(Location::RequiresRegister());
}
locations->SetOut(Location::RequiresRegister(), Location::kOutputOverlap);
}
void IntrinsicCodeGeneratorARM64::VisitStringCompareTo(HInvoke* invoke) {
MacroAssembler* masm = GetVIXLAssembler();
LocationSummary* locations = invoke->GetLocations();
Register str = InputRegisterAt(invoke, 0);
Register arg = InputRegisterAt(invoke, 1);
DCHECK(str.IsW());
DCHECK(arg.IsW());
Register out = OutputRegister(invoke);
Register temp0 = WRegisterFrom(locations->GetTemp(0));
Register temp1 = WRegisterFrom(locations->GetTemp(1));
Register temp2 = WRegisterFrom(locations->GetTemp(2));
Register temp3;
if (mirror::kUseStringCompression) {
temp3 = WRegisterFrom(locations->GetTemp(3));
}
vixl::aarch64::Label loop;
vixl::aarch64::Label find_char_diff;
vixl::aarch64::Label end;
vixl::aarch64::Label different_compression;
// Get offsets of count and value fields within a string object.
const int32_t count_offset = mirror::String::CountOffset().Int32Value();
const int32_t value_offset = mirror::String::ValueOffset().Int32Value();
// Note that the null check must have been done earlier.
DCHECK(!invoke->CanDoImplicitNullCheckOn(invoke->InputAt(0)));
// Take slow path and throw if input can be and is null.
SlowPathCodeARM64* slow_path = nullptr;
const bool can_slow_path = invoke->InputAt(1)->CanBeNull();
if (can_slow_path) {
slow_path = new (codegen_->GetScopedAllocator()) IntrinsicSlowPathARM64(invoke);
codegen_->AddSlowPath(slow_path);
__ Cbz(arg, slow_path->GetEntryLabel());
}
// Reference equality check, return 0 if same reference.
__ Subs(out, str, arg);
__ B(&end, eq);
if (mirror::kUseStringCompression) {
// Load `count` fields of this and argument strings.
__ Ldr(temp3, HeapOperand(str, count_offset));
__ Ldr(temp2, HeapOperand(arg, count_offset));
// Clean out compression flag from lengths.
__ Lsr(temp0, temp3, 1u);
__ Lsr(temp1, temp2, 1u);
} else {
// Load lengths of this and argument strings.
__ Ldr(temp0, HeapOperand(str, count_offset));
__ Ldr(temp1, HeapOperand(arg, count_offset));
}
// out = length diff.
__ Subs(out, temp0, temp1);
// temp0 = min(len(str), len(arg)).
__ Csel(temp0, temp1, temp0, ge);
// Shorter string is empty?
__ Cbz(temp0, &end);
if (mirror::kUseStringCompression) {
// Check if both strings using same compression style to use this comparison loop.
__ Eor(temp2, temp2, Operand(temp3));
// Interleave with compression flag extraction which is needed for both paths
// and also set flags which is needed only for the different compressions path.
__ Ands(temp3.W(), temp3.W(), Operand(1));
__ Tbnz(temp2, 0, &different_compression); // Does not use flags.
}
// Store offset of string value in preparation for comparison loop.
__ Mov(temp1, value_offset);
if (mirror::kUseStringCompression) {
// For string compression, calculate the number of bytes to compare (not chars).
// This could in theory exceed INT32_MAX, so treat temp0 as unsigned.
__ Lsl(temp0, temp0, temp3);
}
UseScratchRegisterScope scratch_scope(masm);
Register temp4 = scratch_scope.AcquireX();
// Assertions that must hold in order to compare strings 8 bytes at a time.
DCHECK_ALIGNED(value_offset, 8);
static_assert(IsAligned<8>(kObjectAlignment), "String of odd length is not zero padded");
const size_t char_size = DataType::Size(DataType::Type::kUint16);
DCHECK_EQ(char_size, 2u);
// Promote temp2 to an X reg, ready for LDR.
temp2 = temp2.X();
// Loop to compare 4x16-bit characters at a time (ok because of string data alignment).
__ Bind(&loop);
__ Ldr(temp4, MemOperand(str.X(), temp1.X()));
__ Ldr(temp2, MemOperand(arg.X(), temp1.X()));
__ Cmp(temp4, temp2);
__ B(ne, &find_char_diff);
__ Add(temp1, temp1, char_size * 4);
// With string compression, we have compared 8 bytes, otherwise 4 chars.
__ Subs(temp0, temp0, (mirror::kUseStringCompression) ? 8 : 4);
__ B(&loop, hi);
__ B(&end);
// Promote temp1 to an X reg, ready for EOR.
temp1 = temp1.X();
// Find the single character difference.
__ Bind(&find_char_diff);
// Get the bit position of the first character that differs.
__ Eor(temp1, temp2, temp4);
__ Rbit(temp1, temp1);
__ Clz(temp1, temp1);
// If the number of chars remaining <= the index where the difference occurs (0-3), then
// the difference occurs outside the remaining string data, so just return length diff (out).
// Unlike ARM, we're doing the comparison in one go here, without the subtraction at the
// find_char_diff_2nd_cmp path, so it doesn't matter whether the comparison is signed or
// unsigned when string compression is disabled.
// When it's enabled, the comparison must be unsigned.
__ Cmp(temp0, Operand(temp1.W(), LSR, (mirror::kUseStringCompression) ? 3 : 4));
__ B(ls, &end);
// Extract the characters and calculate the difference.
if (mirror:: kUseStringCompression) {
__ Bic(temp1, temp1, 0x7);
__ Bic(temp1, temp1, Operand(temp3.X(), LSL, 3u));
} else {
__ Bic(temp1, temp1, 0xf);
}
__ Lsr(temp2, temp2, temp1);
__ Lsr(temp4, temp4, temp1);
if (mirror::kUseStringCompression) {
// Prioritize the case of compressed strings and calculate such result first.
__ Uxtb(temp1, temp4);
__ Sub(out, temp1.W(), Operand(temp2.W(), UXTB));
__ Tbz(temp3, 0u, &end); // If actually compressed, we're done.
}
__ Uxth(temp4, temp4);
__ Sub(out, temp4.W(), Operand(temp2.W(), UXTH));
if (mirror::kUseStringCompression) {
__ B(&end);
__ Bind(&different_compression);
// Comparison for different compression style.
const size_t c_char_size = DataType::Size(DataType::Type::kInt8);
DCHECK_EQ(c_char_size, 1u);
temp1 = temp1.W();
temp2 = temp2.W();
temp4 = temp4.W();
// `temp1` will hold the compressed data pointer, `temp2` the uncompressed data pointer.
// Note that flags have been set by the `str` compression flag extraction to `temp3`
// before branching to the `different_compression` label.
__ Csel(temp1, str, arg, eq); // Pointer to the compressed string.
__ Csel(temp2, str, arg, ne); // Pointer to the uncompressed string.
// We want to free up the temp3, currently holding `str` compression flag, for comparison.
// So, we move it to the bottom bit of the iteration count `temp0` which we then need to treat
// as unsigned. Start by freeing the bit with a LSL and continue further down by a SUB which
// will allow `subs temp0, #2; bhi different_compression_loop` to serve as the loop condition.
__ Lsl(temp0, temp0, 1u);
// Adjust temp1 and temp2 from string pointers to data pointers.
__ Add(temp1, temp1, Operand(value_offset));
__ Add(temp2, temp2, Operand(value_offset));
// Complete the move of the compression flag.
__ Sub(temp0, temp0, Operand(temp3));
vixl::aarch64::Label different_compression_loop;
vixl::aarch64::Label different_compression_diff;
__ Bind(&different_compression_loop);
__ Ldrb(temp4, MemOperand(temp1.X(), c_char_size, PostIndex));
__ Ldrh(temp3, MemOperand(temp2.X(), char_size, PostIndex));
__ Subs(temp4, temp4, Operand(temp3));
__ B(&different_compression_diff, ne);
__ Subs(temp0, temp0, 2);
__ B(&different_compression_loop, hi);
__ B(&end);
// Calculate the difference.
__ Bind(&different_compression_diff);
__ Tst(temp0, Operand(1));
static_assert(static_cast<uint32_t>(mirror::StringCompressionFlag::kCompressed) == 0u,
"Expecting 0=compressed, 1=uncompressed");
__ Cneg(out, temp4, ne);
}
__ Bind(&end);
if (can_slow_path) {
__ Bind(slow_path->GetExitLabel());
}
}
// The cut off for unrolling the loop in String.equals() intrinsic for const strings.
// The normal loop plus the pre-header is 9 instructions without string compression and 12
// instructions with string compression. We can compare up to 8 bytes in 4 instructions
// (LDR+LDR+CMP+BNE) and up to 16 bytes in 5 instructions (LDP+LDP+CMP+CCMP+BNE). Allow up
// to 10 instructions for the unrolled loop.
constexpr size_t kShortConstStringEqualsCutoffInBytes = 32;
static const char* GetConstString(HInstruction* candidate, uint32_t* utf16_length) {
if (candidate->IsLoadString()) {
HLoadString* load_string = candidate->AsLoadString();
const DexFile& dex_file = load_string->GetDexFile();
return dex_file.StringDataAndUtf16LengthByIdx(load_string->GetStringIndex(), utf16_length);
}
return nullptr;
}
void IntrinsicLocationsBuilderARM64::VisitStringEquals(HInvoke* invoke) {
LocationSummary* locations =
new (allocator_) LocationSummary(invoke, LocationSummary::kNoCall, kIntrinsified);
locations->SetInAt(0, Location::RequiresRegister());
locations->SetInAt(1, Location::RequiresRegister());
// For the generic implementation and for long const strings we need a temporary.
// We do not need it for short const strings, up to 8 bytes, see code generation below.
uint32_t const_string_length = 0u;
const char* const_string = GetConstString(invoke->InputAt(0), &const_string_length);
if (const_string == nullptr) {
const_string = GetConstString(invoke->InputAt(1), &const_string_length);
}
bool is_compressed =
mirror::kUseStringCompression &&
const_string != nullptr &&
mirror::String::DexFileStringAllASCII(const_string, const_string_length);
if (const_string == nullptr || const_string_length > (is_compressed ? 8u : 4u)) {
locations->AddTemp(Location::RequiresRegister());
}
// TODO: If the String.equals() is used only for an immediately following HIf, we can
// mark it as emitted-at-use-site and emit branches directly to the appropriate blocks.
// Then we shall need an extra temporary register instead of the output register.
locations->SetOut(Location::RequiresRegister(), Location::kOutputOverlap);
}
void IntrinsicCodeGeneratorARM64::VisitStringEquals(HInvoke* invoke) {
MacroAssembler* masm = GetVIXLAssembler();
LocationSummary* locations = invoke->GetLocations();
Register str = WRegisterFrom(locations->InAt(0));
Register arg = WRegisterFrom(locations->InAt(1));
Register out = XRegisterFrom(locations->Out());
UseScratchRegisterScope scratch_scope(masm);
Register temp = scratch_scope.AcquireW();
Register temp1 = scratch_scope.AcquireW();
vixl::aarch64::Label loop;
vixl::aarch64::Label end;
vixl::aarch64::Label return_true;
vixl::aarch64::Label return_false;
// Get offsets of count, value, and class fields within a string object.
const int32_t count_offset = mirror::String::CountOffset().Int32Value();
const int32_t value_offset = mirror::String::ValueOffset().Int32Value();
const int32_t class_offset = mirror::Object::ClassOffset().Int32Value();
// Note that the null check must have been done earlier.
DCHECK(!invoke->CanDoImplicitNullCheckOn(invoke->InputAt(0)));
StringEqualsOptimizations optimizations(invoke);
if (!optimizations.GetArgumentNotNull()) {
// Check if input is null, return false if it is.
__ Cbz(arg, &return_false);
}
// Reference equality check, return true if same reference.
__ Cmp(str, arg);
__ B(&return_true, eq);
if (!optimizations.GetArgumentIsString()) {
// Instanceof check for the argument by comparing class fields.
// All string objects must have the same type since String cannot be subclassed.
// Receiver must be a string object, so its class field is equal to all strings' class fields.
// If the argument is a string object, its class field must be equal to receiver's class field.
//
// As the String class is expected to be non-movable, we can read the class
// field from String.equals' arguments without read barriers.
AssertNonMovableStringClass();
// /* HeapReference<Class> */ temp = str->klass_
__ Ldr(temp, MemOperand(str.X(), class_offset));
// /* HeapReference<Class> */ temp1 = arg->klass_
__ Ldr(temp1, MemOperand(arg.X(), class_offset));
// Also, because we use the previously loaded class references only in the
// following comparison, we don't need to unpoison them.
__ Cmp(temp, temp1);
__ B(&return_false, ne);
}
// Check if one of the inputs is a const string. Do not special-case both strings
// being const, such cases should be handled by constant folding if needed.
uint32_t const_string_length = 0u;
const char* const_string = GetConstString(invoke->InputAt(0), &const_string_length);
if (const_string == nullptr) {
const_string = GetConstString(invoke->InputAt(1), &const_string_length);
if (const_string != nullptr) {
std::swap(str, arg); // Make sure the const string is in `str`.
}
}
bool is_compressed =
mirror::kUseStringCompression &&
const_string != nullptr &&
mirror::String::DexFileStringAllASCII(const_string, const_string_length);
if (const_string != nullptr) {
// Load `count` field of the argument string and check if it matches the const string.
// Also compares the compression style, if differs return false.
__ Ldr(temp, MemOperand(arg.X(), count_offset));
// Temporarily release temp1 as we may not be able to embed the flagged count in CMP immediate.
scratch_scope.Release(temp1);
__ Cmp(temp, Operand(mirror::String::GetFlaggedCount(const_string_length, is_compressed)));
temp1 = scratch_scope.AcquireW();
__ B(&return_false, ne);
} else {
// Load `count` fields of this and argument strings.
__ Ldr(temp, MemOperand(str.X(), count_offset));
__ Ldr(temp1, MemOperand(arg.X(), count_offset));
// Check if `count` fields are equal, return false if they're not.
// Also compares the compression style, if differs return false.
__ Cmp(temp, temp1);
__ B(&return_false, ne);
}
// Assertions that must hold in order to compare strings 8 bytes at a time.
// Ok to do this because strings are zero-padded to kObjectAlignment.
DCHECK_ALIGNED(value_offset, 8);
static_assert(IsAligned<8>(kObjectAlignment), "String of odd length is not zero padded");
if (const_string != nullptr &&
const_string_length <= (is_compressed ? kShortConstStringEqualsCutoffInBytes
: kShortConstStringEqualsCutoffInBytes / 2u)) {
// Load and compare the contents. Though we know the contents of the short const string
// at compile time, materializing constants may be more code than loading from memory.
int32_t offset = value_offset;
size_t remaining_bytes =
RoundUp(is_compressed ? const_string_length : const_string_length * 2u, 8u);
temp = temp.X();
temp1 = temp1.X();
while (remaining_bytes > sizeof(uint64_t)) {
Register temp2 = XRegisterFrom(locations->GetTemp(0));
__ Ldp(temp, temp1, MemOperand(str.X(), offset));
__ Ldp(temp2, out, MemOperand(arg.X(), offset));
__ Cmp(temp, temp2);
__ Ccmp(temp1, out, NoFlag, eq);
__ B(&return_false, ne);
offset += 2u * sizeof(uint64_t);
remaining_bytes -= 2u * sizeof(uint64_t);
}
if (remaining_bytes != 0u) {
__ Ldr(temp, MemOperand(str.X(), offset));
__ Ldr(temp1, MemOperand(arg.X(), offset));
__ Cmp(temp, temp1);
__ B(&return_false, ne);
}
} else {
// Return true if both strings are empty. Even with string compression `count == 0` means empty.
static_assert(static_cast<uint32_t>(mirror::StringCompressionFlag::kCompressed) == 0u,
"Expecting 0=compressed, 1=uncompressed");
__ Cbz(temp, &return_true);
if (mirror::kUseStringCompression) {
// For string compression, calculate the number of bytes to compare (not chars).
// This could in theory exceed INT32_MAX, so treat temp as unsigned.
__ And(temp1, temp, Operand(1)); // Extract compression flag.
__ Lsr(temp, temp, 1u); // Extract length.
__ Lsl(temp, temp, temp1); // Calculate number of bytes to compare.
}
// Store offset of string value in preparation for comparison loop
__ Mov(temp1, value_offset);
temp1 = temp1.X();
Register temp2 = XRegisterFrom(locations->GetTemp(0));
// Loop to compare strings 8 bytes at a time starting at the front of the string.
__ Bind(&loop);
__ Ldr(out, MemOperand(str.X(), temp1));
__ Ldr(temp2, MemOperand(arg.X(), temp1));
__ Add(temp1, temp1, Operand(sizeof(uint64_t)));
__ Cmp(out, temp2);
__ B(&return_false, ne);
// With string compression, we have compared 8 bytes, otherwise 4 chars.
__ Sub(temp, temp, Operand(mirror::kUseStringCompression ? 8 : 4), SetFlags);
__ B(&loop, hi);
}
// Return true and exit the function.
// If loop does not result in returning false, we return true.
__ Bind(&return_true);
__ Mov(out, 1);
__ B(&end);
// Return false and exit the function.
__ Bind(&return_false);
__ Mov(out, 0);
__ Bind(&end);
}
static void GenerateVisitStringIndexOf(HInvoke* invoke,
MacroAssembler* masm,
CodeGeneratorARM64* codegen,
bool start_at_zero) {
LocationSummary* locations = invoke->GetLocations();
// Note that the null check must have been done earlier.
DCHECK(!invoke->CanDoImplicitNullCheckOn(invoke->InputAt(0)));
// Check for code points > 0xFFFF. Either a slow-path check when we don't know statically,
// or directly dispatch for a large constant, or omit slow-path for a small constant or a char.
SlowPathCodeARM64* slow_path = nullptr;
HInstruction* code_point = invoke->InputAt(1);
if (code_point->IsIntConstant()) {
if (static_cast<uint32_t>(code_point->AsIntConstant()->GetValue()) > 0xFFFFU) {
// Always needs the slow-path. We could directly dispatch to it, but this case should be
// rare, so for simplicity just put the full slow-path down and branch unconditionally.
slow_path = new (codegen->GetScopedAllocator()) IntrinsicSlowPathARM64(invoke);
codegen->AddSlowPath(slow_path);
__ B(slow_path->GetEntryLabel());
__ Bind(slow_path->GetExitLabel());
return;
}
} else if (code_point->GetType() != DataType::Type::kUint16) {
Register char_reg = WRegisterFrom(locations->InAt(1));
__ Tst(char_reg, 0xFFFF0000);
slow_path = new (codegen->GetScopedAllocator()) IntrinsicSlowPathARM64(invoke);
codegen->AddSlowPath(slow_path);
__ B(ne, slow_path->GetEntryLabel());
}
if (start_at_zero) {
// Start-index = 0.
Register tmp_reg = WRegisterFrom(locations->GetTemp(0));
__ Mov(tmp_reg, 0);
}
codegen->InvokeRuntime(kQuickIndexOf, invoke, invoke->GetDexPc(), slow_path);
CheckEntrypointTypes<kQuickIndexOf, int32_t, void*, uint32_t, uint32_t>();
if (slow_path != nullptr) {
__ Bind(slow_path->GetExitLabel());
}
}
void IntrinsicLocationsBuilderARM64::VisitStringIndexOf(HInvoke* invoke) {
LocationSummary* locations = new (allocator_) LocationSummary(
invoke, LocationSummary::kCallOnMainAndSlowPath, kIntrinsified);
// We have a hand-crafted assembly stub that follows the runtime calling convention. So it's
// best to align the inputs accordingly.
InvokeRuntimeCallingConvention calling_convention;
locations->SetInAt(0, LocationFrom(calling_convention.GetRegisterAt(0)));
locations->SetInAt(1, LocationFrom(calling_convention.GetRegisterAt(1)));
locations->SetOut(calling_convention.GetReturnLocation(DataType::Type::kInt32));
// Need to send start_index=0.
locations->AddTemp(LocationFrom(calling_convention.GetRegisterAt(2)));
}
void IntrinsicCodeGeneratorARM64::VisitStringIndexOf(HInvoke* invoke) {
GenerateVisitStringIndexOf(invoke, GetVIXLAssembler(), codegen_, /* start_at_zero= */ true);
}
void IntrinsicLocationsBuilderARM64::VisitStringIndexOfAfter(HInvoke* invoke) {
LocationSummary* locations = new (allocator_) LocationSummary(
invoke, LocationSummary::kCallOnMainAndSlowPath, kIntrinsified);
// We have a hand-crafted assembly stub that follows the runtime calling convention. So it's
// best to align the inputs accordingly.
InvokeRuntimeCallingConvention calling_convention;
locations->SetInAt(0, LocationFrom(calling_convention.GetRegisterAt(0)));
locations->SetInAt(1, LocationFrom(calling_convention.GetRegisterAt(1)));
locations->SetInAt(2, LocationFrom(calling_convention.GetRegisterAt(2)));
locations->SetOut(calling_convention.GetReturnLocation(DataType::Type::kInt32));
}
void IntrinsicCodeGeneratorARM64::VisitStringIndexOfAfter(HInvoke* invoke) {
GenerateVisitStringIndexOf(invoke, GetVIXLAssembler(), codegen_, /* start_at_zero= */ false);
}
void IntrinsicLocationsBuilderARM64::VisitStringNewStringFromBytes(HInvoke* invoke) {
LocationSummary* locations = new (allocator_) LocationSummary(
invoke, LocationSummary::kCallOnMainAndSlowPath, kIntrinsified);
InvokeRuntimeCallingConvention calling_convention;
locations->SetInAt(0, LocationFrom(calling_convention.GetRegisterAt(0)));
locations->SetInAt(1, LocationFrom(calling_convention.GetRegisterAt(1)));
locations->SetInAt(2, LocationFrom(calling_convention.GetRegisterAt(2)));
locations->SetInAt(3, LocationFrom(calling_convention.GetRegisterAt(3)));
locations->SetOut(calling_convention.GetReturnLocation(DataType::Type::kReference));
}
void IntrinsicCodeGeneratorARM64::VisitStringNewStringFromBytes(HInvoke* invoke) {
MacroAssembler* masm = GetVIXLAssembler();
LocationSummary* locations = invoke->GetLocations();
Register byte_array = WRegisterFrom(locations->InAt(0));
__ Cmp(byte_array, 0);
SlowPathCodeARM64* slow_path =
new (codegen_->GetScopedAllocator()) IntrinsicSlowPathARM64(invoke);
codegen_->AddSlowPath(slow_path);
__ B(eq, slow_path->GetEntryLabel());
codegen_->InvokeRuntime(kQuickAllocStringFromBytes, invoke, invoke->GetDexPc(), slow_path);
CheckEntrypointTypes<kQuickAllocStringFromBytes, void*, void*, int32_t, int32_t, int32_t>();
__ Bind(slow_path->GetExitLabel());
}
void IntrinsicLocationsBuilderARM64::VisitStringNewStringFromChars(HInvoke* invoke) {
LocationSummary* locations =
new (allocator_) LocationSummary(invoke, LocationSummary::kCallOnMainOnly, kIntrinsified);
InvokeRuntimeCallingConvention calling_convention;
locations->SetInAt(0, LocationFrom(calling_convention.GetRegisterAt(0)));
locations->SetInAt(1, LocationFrom(calling_convention.GetRegisterAt(1)));
locations->SetInAt(2, LocationFrom(calling_convention.GetRegisterAt(2)));
locations->SetOut(calling_convention.GetReturnLocation(DataType::Type::kReference));
}
void IntrinsicCodeGeneratorARM64::VisitStringNewStringFromChars(HInvoke* invoke) {
// No need to emit code checking whether `locations->InAt(2)` is a null
// pointer, as callers of the native method
//
// java.lang.StringFactory.newStringFromChars(int offset, int charCount, char[] data)
//
// all include a null check on `data` before calling that method.
codegen_->InvokeRuntime(kQuickAllocStringFromChars, invoke, invoke->GetDexPc());
CheckEntrypointTypes<kQuickAllocStringFromChars, void*, int32_t, int32_t, void*>();
}
void IntrinsicLocationsBuilderARM64::VisitStringNewStringFromString(HInvoke* invoke) {
LocationSummary* locations = new (allocator_) LocationSummary(
invoke, LocationSummary::kCallOnMainAndSlowPath, kIntrinsified);
InvokeRuntimeCallingConvention calling_convention;
locations->SetInAt(0, LocationFrom(calling_convention.GetRegisterAt(0)));
locations->SetOut(calling_convention.GetReturnLocation(DataType::Type::kReference));
}
void IntrinsicCodeGeneratorARM64::VisitStringNewStringFromString(HInvoke* invoke) {
MacroAssembler* masm = GetVIXLAssembler();
LocationSummary* locations = invoke->GetLocations();
Register string_to_copy = WRegisterFrom(locations->InAt(0));
__ Cmp(string_to_copy, 0);
SlowPathCodeARM64* slow_path =
new (codegen_->GetScopedAllocator()) IntrinsicSlowPathARM64(invoke);
codegen_->AddSlowPath(slow_path);
__ B(eq, slow_path->GetEntryLabel());
codegen_->InvokeRuntime(kQuickAllocStringFromString, invoke, invoke->GetDexPc(), slow_path);
CheckEntrypointTypes<kQuickAllocStringFromString, void*, void*>();
__ Bind(slow_path->GetExitLabel());
}
static void CreateFPToFPCallLocations(ArenaAllocator* allocator, HInvoke* invoke) {
DCHECK_EQ(invoke->GetNumberOfArguments(), 1U);
DCHECK(DataType::IsFloatingPointType(invoke->InputAt(0)->GetType()));
DCHECK(DataType::IsFloatingPointType(invoke->GetType()));
LocationSummary* const locations =
new (allocator) LocationSummary(invoke, LocationSummary::kCallOnMainOnly, kIntrinsified);
InvokeRuntimeCallingConvention calling_convention;
locations->SetInAt(0, LocationFrom(calling_convention.GetFpuRegisterAt(0)));
locations->SetOut(calling_convention.GetReturnLocation(invoke->GetType()));
}
static void CreateFPFPToFPCallLocations(ArenaAllocator* allocator, HInvoke* invoke) {
DCHECK_EQ(invoke->GetNumberOfArguments(), 2U);
DCHECK(DataType::IsFloatingPointType(invoke->InputAt(0)->GetType()));
DCHECK(DataType::IsFloatingPointType(invoke->InputAt(1)->GetType()));
DCHECK(DataType::IsFloatingPointType(invoke->GetType()));
LocationSummary* const locations =
new (allocator) LocationSummary(invoke, LocationSummary::kCallOnMainOnly, kIntrinsified);
InvokeRuntimeCallingConvention calling_convention;
locations->SetInAt(0, LocationFrom(calling_convention.GetFpuRegisterAt(0)));
locations->SetInAt(1, LocationFrom(calling_convention.GetFpuRegisterAt(1)));
locations->SetOut(calling_convention.GetReturnLocation(invoke->GetType()));
}
static void GenFPToFPCall(HInvoke* invoke,
CodeGeneratorARM64* codegen,
QuickEntrypointEnum entry) {
codegen->InvokeRuntime(entry, invoke, invoke->GetDexPc());
}
void IntrinsicLocationsBuilderARM64::VisitMathCos(HInvoke* invoke) {
CreateFPToFPCallLocations(allocator_, invoke);
}
void IntrinsicCodeGeneratorARM64::VisitMathCos(HInvoke* invoke) {
GenFPToFPCall(invoke, codegen_, kQuickCos);
}
void IntrinsicLocationsBuilderARM64::VisitMathSin(HInvoke* invoke) {
CreateFPToFPCallLocations(allocator_, invoke);
}
void IntrinsicCodeGeneratorARM64::VisitMathSin(HInvoke* invoke) {
GenFPToFPCall(invoke, codegen_, kQuickSin);
}
void IntrinsicLocationsBuilderARM64::VisitMathAcos(HInvoke* invoke) {
CreateFPToFPCallLocations(allocator_, invoke);
}
void IntrinsicCodeGeneratorARM64::VisitMathAcos(HInvoke* invoke) {
GenFPToFPCall(invoke, codegen_, kQuickAcos);
}
void IntrinsicLocationsBuilderARM64::VisitMathAsin(HInvoke* invoke) {
CreateFPToFPCallLocations(allocator_, invoke);
}
void IntrinsicCodeGeneratorARM64::VisitMathAsin(HInvoke* invoke) {
GenFPToFPCall(invoke, codegen_, kQuickAsin);
}
void IntrinsicLocationsBuilderARM64::VisitMathAtan(HInvoke* invoke) {
CreateFPToFPCallLocations(allocator_, invoke);
}
void IntrinsicCodeGeneratorARM64::VisitMathAtan(HInvoke* invoke) {
GenFPToFPCall(invoke, codegen_, kQuickAtan);
}
void IntrinsicLocationsBuilderARM64::VisitMathCbrt(HInvoke* invoke) {
CreateFPToFPCallLocations(allocator_, invoke);
}
void IntrinsicCodeGeneratorARM64::VisitMathCbrt(HInvoke* invoke) {
GenFPToFPCall(invoke, codegen_, kQuickCbrt);
}
void IntrinsicLocationsBuilderARM64::VisitMathCosh(HInvoke* invoke) {
CreateFPToFPCallLocations(allocator_, invoke);
}
void IntrinsicCodeGeneratorARM64::VisitMathCosh(HInvoke* invoke) {
GenFPToFPCall(invoke, codegen_, kQuickCosh);
}
void IntrinsicLocationsBuilderARM64::VisitMathExp(HInvoke* invoke) {
CreateFPToFPCallLocations(allocator_, invoke);
}
void IntrinsicCodeGeneratorARM64::VisitMathExp(HInvoke* invoke) {
GenFPToFPCall(invoke, codegen_, kQuickExp);
}
void IntrinsicLocationsBuilderARM64::VisitMathExpm1(HInvoke* invoke) {
CreateFPToFPCallLocations(allocator_, invoke);
}
void IntrinsicCodeGeneratorARM64::VisitMathExpm1(HInvoke* invoke) {
GenFPToFPCall(invoke, codegen_, kQuickExpm1);
}
void IntrinsicLocationsBuilderARM64::VisitMathLog(HInvoke* invoke) {
CreateFPToFPCallLocations(allocator_, invoke);
}
void IntrinsicCodeGeneratorARM64::VisitMathLog(HInvoke* invoke) {
GenFPToFPCall(invoke, codegen_, kQuickLog);
}
void IntrinsicLocationsBuilderARM64::VisitMathLog10(HInvoke* invoke) {
CreateFPToFPCallLocations(allocator_, invoke);
}
void IntrinsicCodeGeneratorARM64::VisitMathLog10(HInvoke* invoke) {
GenFPToFPCall(invoke, codegen_, kQuickLog10);
}
void IntrinsicLocationsBuilderARM64::VisitMathSinh(HInvoke* invoke) {
CreateFPToFPCallLocations(allocator_, invoke);
}
void IntrinsicCodeGeneratorARM64::VisitMathSinh(HInvoke* invoke) {
GenFPToFPCall(invoke, codegen_, kQuickSinh);
}
void IntrinsicLocationsBuilderARM64::VisitMathTan(HInvoke* invoke) {
CreateFPToFPCallLocations(allocator_, invoke);
}
void IntrinsicCodeGeneratorARM64::VisitMathTan(HInvoke* invoke) {
GenFPToFPCall(invoke, codegen_, kQuickTan);
}
void IntrinsicLocationsBuilderARM64::VisitMathTanh(HInvoke* invoke) {
CreateFPToFPCallLocations(allocator_, invoke);
}
void IntrinsicCodeGeneratorARM64::VisitMathTanh(HInvoke* invoke) {
GenFPToFPCall(invoke, codegen_, kQuickTanh);
}
void IntrinsicLocationsBuilderARM64::VisitMathAtan2(HInvoke* invoke) {
CreateFPFPToFPCallLocations(allocator_, invoke);
}
void IntrinsicCodeGeneratorARM64::VisitMathAtan2(HInvoke* invoke) {
GenFPToFPCall(invoke, codegen_, kQuickAtan2);
}
void IntrinsicLocationsBuilderARM64::VisitMathPow(HInvoke* invoke) {
CreateFPFPToFPCallLocations(allocator_, invoke);
}
void IntrinsicCodeGeneratorARM64::VisitMathPow(HInvoke* invoke) {
GenFPToFPCall(invoke, codegen_, kQuickPow);
}
void IntrinsicLocationsBuilderARM64::VisitMathHypot(HInvoke* invoke) {
CreateFPFPToFPCallLocations(allocator_, invoke);
}
void IntrinsicCodeGeneratorARM64::VisitMathHypot(HInvoke* invoke) {
GenFPToFPCall(invoke, codegen_, kQuickHypot);
}
void IntrinsicLocationsBuilderARM64::VisitMathNextAfter(HInvoke* invoke) {
CreateFPFPToFPCallLocations(allocator_, invoke);
}
void IntrinsicCodeGeneratorARM64::VisitMathNextAfter(HInvoke* invoke) {
GenFPToFPCall(invoke, codegen_, kQuickNextAfter);
}
void IntrinsicLocationsBuilderARM64::VisitStringGetCharsNoCheck(HInvoke* invoke) {
LocationSummary* locations =
new (allocator_) LocationSummary(invoke, LocationSummary::kNoCall, kIntrinsified);
locations->SetInAt(0, Location::RequiresRegister());
locations->SetInAt(1, Location::RequiresRegister());
locations->SetInAt(2, Location::RequiresRegister());
locations->SetInAt(3, Location::RequiresRegister());
locations->SetInAt(4, Location::RequiresRegister());
locations->AddTemp(Location::RequiresRegister());
locations->AddTemp(Location::RequiresRegister());
locations->AddTemp(Location::RequiresRegister());
}
void IntrinsicCodeGeneratorARM64::VisitStringGetCharsNoCheck(HInvoke* invoke) {
MacroAssembler* masm = GetVIXLAssembler();
LocationSummary* locations = invoke->GetLocations();
// Check assumption that sizeof(Char) is 2 (used in scaling below).
const size_t char_size = DataType::Size(DataType::Type::kUint16);
DCHECK_EQ(char_size, 2u);
// Location of data in char array buffer.
const uint32_t data_offset = mirror::Array::DataOffset(char_size).Uint32Value();
// Location of char array data in string.
const uint32_t value_offset = mirror::String::ValueOffset().Uint32Value();
// void getCharsNoCheck(int srcBegin, int srcEnd, char[] dst, int dstBegin);
// Since getChars() calls getCharsNoCheck() - we use registers rather than constants.
Register srcObj = XRegisterFrom(locations->InAt(0));
Register srcBegin = XRegisterFrom(locations->InAt(1));
Register srcEnd = XRegisterFrom(locations->InAt(2));
Register dstObj = XRegisterFrom(locations->InAt(3));
Register dstBegin = XRegisterFrom(locations->InAt(4));
Register src_ptr = XRegisterFrom(locations->GetTemp(0));
Register num_chr = XRegisterFrom(locations->GetTemp(1));
Register tmp1 = XRegisterFrom(locations->GetTemp(2));
UseScratchRegisterScope temps(masm);
Register dst_ptr = temps.AcquireX();
Register tmp2 = temps.AcquireX();
vixl::aarch64::Label done;
vixl::aarch64::Label compressed_string_vector_loop;
vixl::aarch64::Label compressed_string_remainder;
__ Sub(num_chr, srcEnd, srcBegin);
// Early out for valid zero-length retrievals.
__ Cbz(num_chr, &done);
// dst address start to copy to.
__ Add(dst_ptr, dstObj, Operand(data_offset));
__ Add(dst_ptr, dst_ptr, Operand(dstBegin, LSL, 1));
// src address to copy from.
__ Add(src_ptr, srcObj, Operand(value_offset));
vixl::aarch64::Label compressed_string_preloop;
if (mirror::kUseStringCompression) {
// Location of count in string.
const uint32_t count_offset = mirror::String::CountOffset().Uint32Value();
// String's length.
__ Ldr(tmp2, MemOperand(srcObj, count_offset));
__ Tbz(tmp2, 0, &compressed_string_preloop);
}
__ Add(src_ptr, src_ptr, Operand(srcBegin, LSL, 1));
// Do the copy.
vixl::aarch64::Label loop;
vixl::aarch64::Label remainder;
// Save repairing the value of num_chr on the < 8 character path.
__ Subs(tmp1, num_chr, 8);
__ B(lt, &remainder);
// Keep the result of the earlier subs, we are going to fetch at least 8 characters.
__ Mov(num_chr, tmp1);
// Main loop used for longer fetches loads and stores 8x16-bit characters at a time.
// (Unaligned addresses are acceptable here and not worth inlining extra code to rectify.)
__ Bind(&loop);
__ Ldp(tmp1, tmp2, MemOperand(src_ptr, char_size * 8, PostIndex));
__ Subs(num_chr, num_chr, 8);
__ Stp(tmp1, tmp2, MemOperand(dst_ptr, char_size * 8, PostIndex));
__ B(ge, &loop);
__ Adds(num_chr, num_chr, 8);
__ B(eq, &done);
// Main loop for < 8 character case and remainder handling. Loads and stores one
// 16-bit Java character at a time.
__ Bind(&remainder);
__ Ldrh(tmp1, MemOperand(src_ptr, char_size, PostIndex));
__ Subs(num_chr, num_chr, 1);
__ Strh(tmp1, MemOperand(dst_ptr, char_size, PostIndex));
__ B(gt, &remainder);
__ B(&done);
if (mirror::kUseStringCompression) {
// For compressed strings, acquire a SIMD temporary register.
VRegister vtmp1 = temps.AcquireVRegisterOfSize(kQRegSize);
const size_t c_char_size = DataType::Size(DataType::Type::kInt8);
DCHECK_EQ(c_char_size, 1u);
__ Bind(&compressed_string_preloop);
__ Add(src_ptr, src_ptr, Operand(srcBegin));
// Save repairing the value of num_chr on the < 8 character path.
__ Subs(tmp1, num_chr, 8);
__ B(lt, &compressed_string_remainder);
// Keep the result of the earlier subs, we are going to fetch at least 8 characters.
__ Mov(num_chr, tmp1);
// Main loop for compressed src, copying 8 characters (8-bit) to (16-bit) at a time.
// Uses SIMD instructions.
__ Bind(&compressed_string_vector_loop);
__ Ld1(vtmp1.V8B(), MemOperand(src_ptr, c_char_size * 8, PostIndex));
__ Subs(num_chr, num_chr, 8);
__ Uxtl(vtmp1.V8H(), vtmp1.V8B());
__ St1(vtmp1.V8H(), MemOperand(dst_ptr, char_size * 8, PostIndex));
__ B(ge, &compressed_string_vector_loop);
__ Adds(num_chr, num_chr, 8);
__ B(eq, &done);
// Loop for < 8 character case and remainder handling with a compressed src.
// Copies 1 character (8-bit) to (16-bit) at a time.
__ Bind(&compressed_string_remainder);
__ Ldrb(tmp1, MemOperand(src_ptr, c_char_size, PostIndex));
__ Strh(tmp1, MemOperand(dst_ptr, char_size, PostIndex));
__ Subs(num_chr, num_chr, Operand(1));
__ B(gt, &compressed_string_remainder);
}
__ Bind(&done);
}
// Mirrors ARRAYCOPY_SHORT_CHAR_ARRAY_THRESHOLD in libcore, so we can choose to use the native
// implementation there for longer copy lengths.
static constexpr int32_t kSystemArrayCopyCharThreshold = 32;
static void SetSystemArrayCopyLocationRequires(LocationSummary* locations,
uint32_t at,
HInstruction* input) {
HIntConstant* const_input = input->AsIntConstant();
if (const_input != nullptr && !vixl::aarch64::Assembler::IsImmAddSub(const_input->GetValue())) {
locations->SetInAt(at, Location::RequiresRegister());
} else {
locations->SetInAt(at, Location::RegisterOrConstant(input));
}
}
void IntrinsicLocationsBuilderARM64::VisitSystemArrayCopyChar(HInvoke* invoke) {
// Check to see if we have known failures that will cause us to have to bail out
// to the runtime, and just generate the runtime call directly.
HIntConstant* src_pos = invoke->InputAt(1)->AsIntConstant();
HIntConstant* dst_pos = invoke->InputAt(3)->AsIntConstant();
// The positions must be non-negative.
if ((src_pos != nullptr && src_pos->GetValue() < 0) ||
(dst_pos != nullptr && dst_pos->GetValue() < 0)) {
// We will have to fail anyways.
return;
}
// The length must be >= 0 and not so long that we would (currently) prefer libcore's
// native implementation.
HIntConstant* length = invoke->InputAt(4)->AsIntConstant();
if (length != nullptr) {
int32_t len = length->GetValue();
if (len < 0 || len > kSystemArrayCopyCharThreshold) {
// Just call as normal.
return;
}
}
ArenaAllocator* allocator = invoke->GetBlock()->GetGraph()->GetAllocator();
LocationSummary* locations =
new (allocator) LocationSummary(invoke, LocationSummary::kCallOnSlowPath, kIntrinsified);
// arraycopy(char[] src, int src_pos, char[] dst, int dst_pos, int length).
locations->SetInAt(0, Location::RequiresRegister());
SetSystemArrayCopyLocationRequires(locations, 1, invoke->InputAt(1));
locations->SetInAt(2, Location::RequiresRegister());
SetSystemArrayCopyLocationRequires(locations, 3, invoke->InputAt(3));
SetSystemArrayCopyLocationRequires(locations, 4, invoke->InputAt(4));
locations->AddTemp(Location::RequiresRegister());
locations->AddTemp(Location::RequiresRegister());
locations->AddTemp(Location::RequiresRegister());
}
static void CheckSystemArrayCopyPosition(MacroAssembler* masm,
const Location& pos,
const Register& input,
const Location& length,
SlowPathCodeARM64* slow_path,
const Register& temp,
bool length_is_input_length = false) {
const int32_t length_offset = mirror::Array::LengthOffset().Int32Value();
if (pos.IsConstant()) {
int32_t pos_const = pos.GetConstant()->AsIntConstant()->GetValue();
if (pos_const == 0) {
if (!length_is_input_length) {
// Check that length(input) >= length.
__ Ldr(temp, MemOperand(input, length_offset));
__ Cmp(temp, OperandFrom(length, DataType::Type::kInt32));
__ B(slow_path->GetEntryLabel(), lt);
}
} else {
// Check that length(input) >= pos.
__ Ldr(temp, MemOperand(input, length_offset));
__ Subs(temp, temp, pos_const);
__ B(slow_path->GetEntryLabel(), lt);
// Check that (length(input) - pos) >= length.
__ Cmp(temp, OperandFrom(length, DataType::Type::kInt32));
__ B(slow_path->GetEntryLabel(), lt);
}
} else if (length_is_input_length) {
// The only way the copy can succeed is if pos is zero.
__ Cbnz(WRegisterFrom(pos), slow_path->GetEntryLabel());
} else {
// Check that pos >= 0.
Register pos_reg = WRegisterFrom(pos);
__ Tbnz(pos_reg, pos_reg.GetSizeInBits() - 1, slow_path->GetEntryLabel());
// Check that pos <= length(input) && (length(input) - pos) >= length.
__ Ldr(temp, MemOperand(input, length_offset));
__ Subs(temp, temp, pos_reg);
// Ccmp if length(input) >= pos, else definitely bail to slow path (N!=V == lt).
__ Ccmp(temp, OperandFrom(length, DataType::Type::kInt32), NFlag, ge);
__ B(slow_path->GetEntryLabel(), lt);
}
}
// Compute base source address, base destination address, and end
// source address for System.arraycopy* intrinsics in `src_base`,
// `dst_base` and `src_end` respectively.
static void GenSystemArrayCopyAddresses(MacroAssembler* masm,
DataType::Type type,
const Register& src,
const Location& src_pos,
const Register& dst,
const Location& dst_pos,
const Location& copy_length,
const Register& src_base,
const Register& dst_base,
const Register& src_end) {
// This routine is used by the SystemArrayCopy and the SystemArrayCopyChar intrinsics.
DCHECK(type == DataType::Type::kReference || type == DataType::Type::kUint16)
<< "Unexpected element type: " << type;
const int32_t element_size = DataType::Size(type);
const int32_t element_size_shift = DataType::SizeShift(type);
const uint32_t data_offset = mirror::Array::DataOffset(element_size).Uint32Value();
if (src_pos.IsConstant()) {
int32_t constant = src_pos.GetConstant()->AsIntConstant()->GetValue();
__ Add(src_base, src, element_size * constant + data_offset);
} else {
__ Add(src_base, src, data_offset);
__ Add(src_base, src_base, Operand(XRegisterFrom(src_pos), LSL, element_size_shift));
}
if (dst_pos.IsConstant()) {
int32_t constant = dst_pos.GetConstant()->AsIntConstant()->GetValue();
__ Add(dst_base, dst, element_size * constant + data_offset);
} else {
__ Add(dst_base, dst, data_offset);
__ Add(dst_base, dst_base, Operand(XRegisterFrom(dst_pos), LSL, element_size_shift));
}
if (copy_length.IsConstant()) {
int32_t constant = copy_length.GetConstant()->AsIntConstant()->GetValue();
__ Add(src_end, src_base, element_size * constant);
} else {
__ Add(src_end, src_base, Operand(XRegisterFrom(copy_length), LSL, element_size_shift));
}
}
void IntrinsicCodeGeneratorARM64::VisitSystemArrayCopyChar(HInvoke* invoke) {
MacroAssembler* masm = GetVIXLAssembler();
LocationSummary* locations = invoke->GetLocations();
Register src = XRegisterFrom(locations->InAt(0));
Location src_pos = locations->InAt(1);
Register dst = XRegisterFrom(locations->InAt(2));
Location dst_pos = locations->InAt(3);
Location length = locations->InAt(4);
SlowPathCodeARM64* slow_path =
new (codegen_->GetScopedAllocator()) IntrinsicSlowPathARM64(invoke);
codegen_->AddSlowPath(slow_path);
// If source and destination are the same, take the slow path. Overlapping copy regions must be
// copied in reverse and we can't know in all cases if it's needed.
__ Cmp(src, dst);
__ B(slow_path->GetEntryLabel(), eq);
// Bail out if the source is null.
__ Cbz(src, slow_path->GetEntryLabel());
// Bail out if the destination is null.
__ Cbz(dst, slow_path->GetEntryLabel());
if (!length.IsConstant()) {
// Merge the following two comparisons into one:
// If the length is negative, bail out (delegate to libcore's native implementation).
// If the length > 32 then (currently) prefer libcore's native implementation.
__ Cmp(WRegisterFrom(length), kSystemArrayCopyCharThreshold);
__ B(slow_path->GetEntryLabel(), hi);
} else {
// We have already checked in the LocationsBuilder for the constant case.
DCHECK_GE(length.GetConstant()->AsIntConstant()->GetValue(), 0);
DCHECK_LE(length.GetConstant()->AsIntConstant()->GetValue(), 32);
}
Register src_curr_addr = WRegisterFrom(locations->GetTemp(0));
Register dst_curr_addr = WRegisterFrom(locations->GetTemp(1));
Register src_stop_addr = WRegisterFrom(locations->GetTemp(2));
CheckSystemArrayCopyPosition(masm,
src_pos,
src,
length,
slow_path,
src_curr_addr,
false);
CheckSystemArrayCopyPosition(masm,
dst_pos,
dst,
length,
slow_path,
src_curr_addr,
false);
src_curr_addr = src_curr_addr.X();
dst_curr_addr = dst_curr_addr.X();
src_stop_addr = src_stop_addr.X();
GenSystemArrayCopyAddresses(masm,
DataType::Type::kUint16,
src,
src_pos,
dst,
dst_pos,
length,
src_curr_addr,
dst_curr_addr,
src_stop_addr);
// Iterate over the arrays and do a raw copy of the chars.
const int32_t char_size = DataType::Size(DataType::Type::kUint16);
UseScratchRegisterScope temps(masm);
Register tmp = temps.AcquireW();
vixl::aarch64::Label loop, done;
__ Bind(&loop);
__ Cmp(src_curr_addr, src_stop_addr);
__ B(&done, eq);
__ Ldrh(tmp, MemOperand(src_curr_addr, char_size, PostIndex));
__ Strh(tmp, MemOperand(dst_curr_addr, char_size, PostIndex));
__ B(&loop);
__ Bind(&done);
__ Bind(slow_path->GetExitLabel());
}
// We can choose to use the native implementation there for longer copy lengths.
static constexpr int32_t kSystemArrayCopyThreshold = 128;
// CodeGenerator::CreateSystemArrayCopyLocationSummary use three temporary registers.
// We want to use two temporary registers in order to reduce the register pressure in arm64.
// So we don't use the CodeGenerator::CreateSystemArrayCopyLocationSummary.
void IntrinsicLocationsBuilderARM64::VisitSystemArrayCopy(HInvoke* invoke) {
// The only read barrier implementation supporting the
// SystemArrayCopy intrinsic is the Baker-style read barriers.
if (kEmitCompilerReadBarrier && !kUseBakerReadBarrier) {
return;
}
// Check to see if we have known failures that will cause us to have to bail out
// to the runtime, and just generate the runtime call directly.
HIntConstant* src_pos = invoke->InputAt(1)->AsIntConstant();
HIntConstant* dest_pos = invoke->InputAt(3)->AsIntConstant();
// The positions must be non-negative.
if ((src_pos != nullptr && src_pos->GetValue() < 0) ||
(dest_pos != nullptr && dest_pos->GetValue() < 0)) {
// We will have to fail anyways.
return;
}
// The length must be >= 0.
HIntConstant* length = invoke->InputAt(4)->AsIntConstant();
if (length != nullptr) {
int32_t len = length->GetValue();
if (len < 0 || len >= kSystemArrayCopyThreshold) {
// Just call as normal.
return;
}
}
SystemArrayCopyOptimizations optimizations(invoke);
if (optimizations.GetDestinationIsSource()) {
if (src_pos != nullptr && dest_pos != nullptr && src_pos->GetValue() < dest_pos->GetValue()) {
// We only support backward copying if source and destination are the same.
return;
}
}
if (optimizations.GetDestinationIsPrimitiveArray() || optimizations.GetSourceIsPrimitiveArray()) {
// We currently don't intrinsify primitive copying.
return;
}
ArenaAllocator* allocator = invoke->GetBlock()->GetGraph()->GetAllocator();
LocationSummary* locations =
new (allocator) LocationSummary(invoke, LocationSummary::kCallOnSlowPath, kIntrinsified);
// arraycopy(Object src, int src_pos, Object dest, int dest_pos, int length).
locations->SetInAt(0, Location::RequiresRegister());
SetSystemArrayCopyLocationRequires(locations, 1, invoke->InputAt(1));
locations->SetInAt(2, Location::RequiresRegister());
SetSystemArrayCopyLocationRequires(locations, 3, invoke->InputAt(3));
SetSystemArrayCopyLocationRequires(locations, 4, invoke->InputAt(4));
locations->AddTemp(Location::RequiresRegister());
locations->AddTemp(Location::RequiresRegister());
if (kEmitCompilerReadBarrier && kUseBakerReadBarrier) {
// Temporary register IP0, obtained from the VIXL scratch register
// pool, cannot be used in ReadBarrierSystemArrayCopySlowPathARM64
// (because that register is clobbered by ReadBarrierMarkRegX
// entry points). It cannot be used in calls to
// CodeGeneratorARM64::GenerateFieldLoadWithBakerReadBarrier
// either. For these reasons, get a third extra temporary register
// from the register allocator.
locations->AddTemp(Location::RequiresRegister());
} else {
// Cases other than Baker read barriers: the third temporary will
// be acquired from the VIXL scratch register pool.
}
}
void IntrinsicCodeGeneratorARM64::VisitSystemArrayCopy(HInvoke* invoke) {
// The only read barrier implementation supporting the
// SystemArrayCopy intrinsic is the Baker-style read barriers.
DCHECK(!kEmitCompilerReadBarrier || kUseBakerReadBarrier);
MacroAssembler* masm = GetVIXLAssembler();
LocationSummary* locations = invoke->GetLocations();
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();
uint32_t monitor_offset = mirror::Object::MonitorOffset().Int32Value();
Register src = XRegisterFrom(locations->InAt(0));
Location src_pos = locations->InAt(1);
Register dest = XRegisterFrom(locations->InAt(2));
Location dest_pos = locations->InAt(3);
Location length = locations->InAt(4);
Register temp1 = WRegisterFrom(locations->GetTemp(0));
Location temp1_loc = LocationFrom(temp1);
Register temp2 = WRegisterFrom(locations->GetTemp(1));
Location temp2_loc = LocationFrom(temp2);
SlowPathCodeARM64* intrinsic_slow_path =
new (codegen_->GetScopedAllocator()) IntrinsicSlowPathARM64(invoke);
codegen_->AddSlowPath(intrinsic_slow_path);
vixl::aarch64::Label conditions_on_positions_validated;
SystemArrayCopyOptimizations optimizations(invoke);
// If source and destination are the same, we go to slow path if we need to do
// forward copying.
if (src_pos.IsConstant()) {
int32_t src_pos_constant = src_pos.GetConstant()->AsIntConstant()->GetValue();
if (dest_pos.IsConstant()) {
int32_t dest_pos_constant = dest_pos.GetConstant()->AsIntConstant()->GetValue();
if (optimizations.GetDestinationIsSource()) {
// Checked when building locations.
DCHECK_GE(src_pos_constant, dest_pos_constant);
} else if (src_pos_constant < dest_pos_constant) {
__ Cmp(src, dest);
__ B(intrinsic_slow_path->GetEntryLabel(), eq);
}
// Checked when building locations.
DCHECK(!optimizations.GetDestinationIsSource()
|| (src_pos_constant >= dest_pos.GetConstant()->AsIntConstant()->GetValue()));
} else {
if (!optimizations.GetDestinationIsSource()) {
__ Cmp(src, dest);
__ B(&conditions_on_positions_validated, ne);
}
__ Cmp(WRegisterFrom(dest_pos), src_pos_constant);
__ B(intrinsic_slow_path->GetEntryLabel(), gt);
}
} else {
if (!optimizations.GetDestinationIsSource()) {
__ Cmp(src, dest);
__ B(&conditions_on_positions_validated, ne);
}
__ Cmp(RegisterFrom(src_pos, invoke->InputAt(1)->GetType()),
OperandFrom(dest_pos, invoke->InputAt(3)->GetType()));
__ B(intrinsic_slow_path->GetEntryLabel(), lt);
}
__ Bind(&conditions_on_positions_validated);
if (!optimizations.GetSourceIsNotNull()) {
// Bail out if the source is null.
__ Cbz(src, intrinsic_slow_path->GetEntryLabel());
}
if (!optimizations.GetDestinationIsNotNull() && !optimizations.GetDestinationIsSource()) {
// Bail out if the destination is null.
__ Cbz(dest, intrinsic_slow_path->GetEntryLabel());
}
// We have already checked in the LocationsBuilder for the constant case.
if (!length.IsConstant() &&
!optimizations.GetCountIsSourceLength() &&
!optimizations.GetCountIsDestinationLength()) {
// Merge the following two comparisons into one:
// If the length is negative, bail out (delegate to libcore's native implementation).
// If the length >= 128 then (currently) prefer native implementation.
__ Cmp(WRegisterFrom(length), kSystemArrayCopyThreshold);
__ B(intrinsic_slow_path->GetEntryLabel(), hs);
}
// Validity checks: source.
CheckSystemArrayCopyPosition(masm,
src_pos,
src,
length,
intrinsic_slow_path,
temp1,
optimizations.GetCountIsSourceLength());
// Validity checks: dest.
CheckSystemArrayCopyPosition(masm,
dest_pos,
dest,
length,
intrinsic_slow_path,
temp1,
optimizations.GetCountIsDestinationLength());
{
// We use a block to end the scratch scope before the write barrier, thus
// freeing the temporary registers so they can be used in `MarkGCCard`.
UseScratchRegisterScope temps(masm);
Location temp3_loc; // Used only for Baker read barrier.
Register temp3;
if (kEmitCompilerReadBarrier && kUseBakerReadBarrier) {
temp3_loc = locations->GetTemp(2);
temp3 = WRegisterFrom(temp3_loc);
} else {
temp3 = temps.AcquireW();
}
if (!optimizations.GetDoesNotNeedTypeCheck()) {
// Check whether all elements of the source array are assignable to the component
// type of the destination array. We do two checks: the classes are the same,
// or the destination is Object[]. If none of these checks succeed, we go to the
// slow path.
if (kEmitCompilerReadBarrier && kUseBakerReadBarrier) {
if (!optimizations.GetSourceIsNonPrimitiveArray()) {
// /* HeapReference<Class> */ temp1 = src->klass_
codegen_->GenerateFieldLoadWithBakerReadBarrier(invoke,
temp1_loc,
src.W(),
class_offset,
temp3_loc,
/* needs_null_check= */ false,
/* use_load_acquire= */ false);
// Bail out if the source is not a non primitive array.
// /* HeapReference<Class> */ temp1 = temp1->component_type_
codegen_->GenerateFieldLoadWithBakerReadBarrier(invoke,
temp1_loc,
temp1,
component_offset,
temp3_loc,
/* needs_null_check= */ false,
/* use_load_acquire= */ false);
__ Cbz(temp1, intrinsic_slow_path->GetEntryLabel());
// If heap poisoning is enabled, `temp1` has been unpoisoned
// by the the previous call to GenerateFieldLoadWithBakerReadBarrier.
// /* uint16_t */ temp1 = static_cast<uint16>(temp1->primitive_type_);
__ Ldrh(temp1, HeapOperand(temp1, primitive_offset));
static_assert(Primitive::kPrimNot == 0, "Expected 0 for kPrimNot");
__ Cbnz(temp1, intrinsic_slow_path->GetEntryLabel());
}
// /* HeapReference<Class> */ temp1 = dest->klass_
codegen_->GenerateFieldLoadWithBakerReadBarrier(invoke,
temp1_loc,
dest.W(),
class_offset,
temp3_loc,
/* needs_null_check= */ false,
/* use_load_acquire= */ false);
if (!optimizations.GetDestinationIsNonPrimitiveArray()) {
// Bail out if the destination is not a non primitive array.
//
// Register `temp1` is not trashed by the read barrier emitted
// by GenerateFieldLoadWithBakerReadBarrier below, as that
// method produces a call to a ReadBarrierMarkRegX entry point,
// which saves all potentially live registers, including
// temporaries such a `temp1`.
// /* HeapReference<Class> */ temp2 = temp1->component_type_
codegen_->GenerateFieldLoadWithBakerReadBarrier(invoke,
temp2_loc,
temp1,
component_offset,
temp3_loc,
/* needs_null_check= */ false,
/* use_load_acquire= */ false);
__ Cbz(temp2, intrinsic_slow_path->GetEntryLabel());
// If heap poisoning is enabled, `temp2` has been unpoisoned
// by the the previous call to GenerateFieldLoadWithBakerReadBarrier.
// /* uint16_t */ temp2 = static_cast<uint16>(temp2->primitive_type_);
__ Ldrh(temp2, HeapOperand(temp2, primitive_offset));
static_assert(Primitive::kPrimNot == 0, "Expected 0 for kPrimNot");
__ Cbnz(temp2, intrinsic_slow_path->GetEntryLabel());
}
// For the same reason given earlier, `temp1` is not trashed by the
// read barrier emitted by GenerateFieldLoadWithBakerReadBarrier below.
// /* HeapReference<Class> */ temp2 = src->klass_
codegen_->GenerateFieldLoadWithBakerReadBarrier(invoke,
temp2_loc,
src.W(),
class_offset,
temp3_loc,
/* needs_null_check= */ false,
/* use_load_acquire= */ false);
// Note: if heap poisoning is on, we are comparing two unpoisoned references here.
__ Cmp(temp1, temp2);
if (optimizations.GetDestinationIsTypedObjectArray()) {
vixl::aarch64::Label do_copy;
__ B(&do_copy, eq);
// /* HeapReference<Class> */ temp1 = temp1->component_type_
codegen_->GenerateFieldLoadWithBakerReadBarrier(invoke,
temp1_loc,
temp1,
component_offset,
temp3_loc,
/* needs_null_check= */ false,
/* use_load_acquire= */ false);
// /* HeapReference<Class> */ temp1 = temp1->super_class_
// We do not need to emit a read barrier for the following
// heap reference load, as `temp1` is only used in a
// comparison with null below, and this reference is not
// kept afterwards.
__ Ldr(temp1, HeapOperand(temp1, super_offset));
__ Cbnz(temp1, intrinsic_slow_path->GetEntryLabel());
__ Bind(&do_copy);
} else {
__ B(intrinsic_slow_path->GetEntryLabel(), ne);
}
} else {
// Non read barrier code.
// /* HeapReference<Class> */ temp1 = dest->klass_
__ Ldr(temp1, MemOperand(dest, class_offset));
// /* HeapReference<Class> */ temp2 = src->klass_
__ Ldr(temp2, MemOperand(src, class_offset));
bool did_unpoison = false;
if (!optimizations.GetDestinationIsNonPrimitiveArray() ||
!optimizations.GetSourceIsNonPrimitiveArray()) {
// One or two of the references need to be unpoisoned. Unpoison them
// both to make the identity check valid.
codegen_->GetAssembler()->MaybeUnpoisonHeapReference(temp1);
codegen_->GetAssembler()->MaybeUnpoisonHeapReference(temp2);
did_unpoison = true;
}
if (!optimizations.GetDestinationIsNonPrimitiveArray()) {
// Bail out if the destination is not a non primitive array.
// /* HeapReference<Class> */ temp3 = temp1->component_type_
__ Ldr(temp3, HeapOperand(temp1, component_offset));
__ Cbz(temp3, intrinsic_slow_path->GetEntryLabel());
codegen_->GetAssembler()->MaybeUnpoisonHeapReference(temp3);
// /* uint16_t */ temp3 = static_cast<uint16>(temp3->primitive_type_);
__ Ldrh(temp3, HeapOperand(temp3, primitive_offset));
static_assert(Primitive::kPrimNot == 0, "Expected 0 for kPrimNot");
__ Cbnz(temp3, intrinsic_slow_path->GetEntryLabel());
}
if (!optimizations.GetSourceIsNonPrimitiveArray()) {
// Bail out if the source is not a non primitive array.
// /* HeapReference<Class> */ temp3 = temp2->component_type_
__ Ldr(temp3, HeapOperand(temp2, component_offset));
__ Cbz(temp3, intrinsic_slow_path->GetEntryLabel());
codegen_->GetAssembler()->MaybeUnpoisonHeapReference(temp3);
// /* uint16_t */ temp3 = static_cast<uint16>(temp3->primitive_type_);
__ Ldrh(temp3, HeapOperand(temp3, primitive_offset));
static_assert(Primitive::kPrimNot == 0, "Expected 0 for kPrimNot");
__ Cbnz(temp3, intrinsic_slow_path->GetEntryLabel());
}
__ Cmp(temp1, temp2);
if (optimizations.GetDestinationIsTypedObjectArray()) {
vixl::aarch64::Label do_copy;
__ B(&do_copy, eq);
if (!did_unpoison) {
codegen_->GetAssembler()->MaybeUnpoisonHeapReference(temp1);
}
// /* HeapReference<Class> */ temp1 = temp1->component_type_
__ Ldr(temp1, HeapOperand(temp1, component_offset));
codegen_->GetAssembler()->MaybeUnpoisonHeapReference(temp1);
// /* HeapReference<Class> */ temp1 = temp1->super_class_
__ Ldr(temp1, HeapOperand(temp1, super_offset));
// No need to unpoison the result, we're comparing against null.
__ Cbnz(temp1, intrinsic_slow_path->GetEntryLabel());
__ Bind(&do_copy);
} else {
__ B(intrinsic_slow_path->GetEntryLabel(), ne);
}
}
} else if (!optimizations.GetSourceIsNonPrimitiveArray()) {
DCHECK(optimizations.GetDestinationIsNonPrimitiveArray());
// Bail out if the source is not a non primitive array.
if (kEmitCompilerReadBarrier && kUseBakerReadBarrier) {
// /* HeapReference<Class> */ temp1 = src->klass_
codegen_->GenerateFieldLoadWithBakerReadBarrier(invoke,
temp1_loc,
src.W(),
class_offset,
temp3_loc,
/* needs_null_check= */ false,
/* use_load_acquire= */ false);
// /* HeapReference<Class> */ temp2 = temp1->component_type_
codegen_->GenerateFieldLoadWithBakerReadBarrier(invoke,
temp2_loc,
temp1,
component_offset,
temp3_loc,
/* needs_null_check= */ false,
/* use_load_acquire= */ false);
__ Cbz(temp2, intrinsic_slow_path->GetEntryLabel());
// If heap poisoning is enabled, `temp2` has been unpoisoned
// by the the previous call to GenerateFieldLoadWithBakerReadBarrier.
} else {
// /* HeapReference<Class> */ temp1 = src->klass_
__ Ldr(temp1, HeapOperand(src.W(), class_offset));
codegen_->GetAssembler()->MaybeUnpoisonHeapReference(temp1);
// /* HeapReference<Class> */ temp2 = temp1->component_type_
__ Ldr(temp2, HeapOperand(temp1, component_offset));
__ Cbz(temp2, intrinsic_slow_path->GetEntryLabel());
codegen_->GetAssembler()->MaybeUnpoisonHeapReference(temp2);
}
// /* uint16_t */ temp2 = static_cast<uint16>(temp2->primitive_type_);
__ Ldrh(temp2, HeapOperand(temp2, primitive_offset));
static_assert(Primitive::kPrimNot == 0, "Expected 0 for kPrimNot");
__ Cbnz(temp2, intrinsic_slow_path->GetEntryLabel());
}
if (length.IsConstant() && length.GetConstant()->AsIntConstant()->GetValue() == 0) {
// Null constant length: not need to emit the loop code at all.
} else {
Register src_curr_addr = temp1.X();
Register dst_curr_addr = temp2.X();
Register src_stop_addr = temp3.X();
vixl::aarch64::Label done;
const DataType::Type type = DataType::Type::kReference;
const int32_t element_size = DataType::Size(type);
if (length.IsRegister()) {
// Don't enter the copy loop if the length is null.
__ Cbz(WRegisterFrom(length), &done);
}
if (kEmitCompilerReadBarrier && kUseBakerReadBarrier) {
// TODO: Also convert this intrinsic to the IsGcMarking strategy?
// SystemArrayCopy implementation for Baker read barriers (see
// also CodeGeneratorARM64::GenerateReferenceLoadWithBakerReadBarrier):
//
// uint32_t rb_state = Lockword(src->monitor_).ReadBarrierState();
// lfence; // Load fence or artificial data dependency to prevent load-load reordering
// bool is_gray = (rb_state == ReadBarrier::GrayState());
// if (is_gray) {
// // Slow-path copy.
// do {
// *dest_ptr++ = MaybePoison(ReadBarrier::Mark(MaybeUnpoison(*src_ptr++)));
// } while (src_ptr != end_ptr)
// } else {
// // Fast-path copy.
// do {
// *dest_ptr++ = *src_ptr++;
// } while (src_ptr != end_ptr)
// }
// Make sure `tmp` is not IP0, as it is clobbered by
// ReadBarrierMarkRegX entry points in
// ReadBarrierSystemArrayCopySlowPathARM64.
DCHECK(temps.IsAvailable(ip0));
temps.Exclude(ip0);
Register tmp = temps.AcquireW();
DCHECK_NE(LocationFrom(tmp).reg(), IP0);
// Put IP0 back in the pool so that VIXL has at least one
// scratch register available to emit macro-instructions (note
// that IP1 is already used for `tmp`). Indeed some
// macro-instructions used in GenSystemArrayCopyAddresses
// (invoked hereunder) may require a scratch register (for
// instance to emit a load with a large constant offset).
temps.Include(ip0);
// /* int32_t */ monitor = src->monitor_
__ Ldr(tmp, HeapOperand(src.W(), monitor_offset));
// /* LockWord */ lock_word = LockWord(monitor)
static_assert(sizeof(LockWord) == sizeof(int32_t),
"art::LockWord and int32_t have different sizes.");
// Introduce a dependency on the lock_word including rb_state,
// to prevent load-load reordering, and without using
// a memory barrier (which would be more expensive).
// `src` is unchanged by this operation, but its value now depends
// on `tmp`.
__ Add(src.X(), src.X(), Operand(tmp.X(), LSR, 32));
// Compute base source address, base destination address, and end
// source address for System.arraycopy* intrinsics in `src_base`,
// `dst_base` and `src_end` respectively.
// Note that `src_curr_addr` is computed from from `src` (and
// `src_pos`) here, and thus honors the artificial dependency
// of `src` on `tmp`.
GenSystemArrayCopyAddresses(masm,
type,
src,
src_pos,
dest,
dest_pos,
length,
src_curr_addr,
dst_curr_addr,
src_stop_addr);
// Slow path used to copy array when `src` is gray.
SlowPathCodeARM64* read_barrier_slow_path =
new (codegen_->GetScopedAllocator()) ReadBarrierSystemArrayCopySlowPathARM64(
invoke, LocationFrom(tmp));
codegen_->AddSlowPath(read_barrier_slow_path);
// Given the numeric representation, it's enough to check the low bit of the rb_state.
static_assert(ReadBarrier::NonGrayState() == 0, "Expecting non-gray to have value 0");
static_assert(ReadBarrier::GrayState() == 1, "Expecting gray to have value 1");
__ Tbnz(tmp, LockWord::kReadBarrierStateShift, read_barrier_slow_path->GetEntryLabel());
// Fast-path copy.
// Iterate over the arrays and do a raw copy of the objects. We don't need to
// poison/unpoison.
vixl::aarch64::Label loop;
__ Bind(&loop);
__ Ldr(tmp, MemOperand(src_curr_addr, element_size, PostIndex));
__ Str(tmp, MemOperand(dst_curr_addr, element_size, PostIndex));
__ Cmp(src_curr_addr, src_stop_addr);
__ B(&loop, ne);
__ Bind(read_barrier_slow_path->GetExitLabel());
} else {
// Non read barrier code.
// Compute base source address, base destination address, and end
// source address for System.arraycopy* intrinsics in `src_base`,
// `dst_base` and `src_end` respectively.
GenSystemArrayCopyAddresses(masm,
type,
src,
src_pos,
dest,
dest_pos,
length,
src_curr_addr,
dst_curr_addr,
src_stop_addr);
// Iterate over the arrays and do a raw copy of the objects. We don't need to
// poison/unpoison.
vixl::aarch64::Label loop;
__ Bind(&loop);
{
Register tmp = temps.AcquireW();
__ Ldr(tmp, MemOperand(src_curr_addr, element_size, PostIndex));
__ Str(tmp, MemOperand(dst_curr_addr, element_size, PostIndex));
}
__ Cmp(src_curr_addr, src_stop_addr);
__ B(&loop, ne);
}
__ Bind(&done);
}
}
// We only need one card marking on the destination array.
codegen_->MarkGCCard(dest.W(), Register(), /* value_can_be_null= */ false);
__ Bind(intrinsic_slow_path->GetExitLabel());
}
static void GenIsInfinite(LocationSummary* locations,
bool is64bit,
MacroAssembler* masm) {
Operand infinity(0);
Operand tst_mask(0);
Register out;
if (is64bit) {
infinity = Operand(kPositiveInfinityDouble);
tst_mask = MaskLeastSignificant<uint64_t>(63);
out = XRegisterFrom(locations->Out());
} else {
infinity = Operand(kPositiveInfinityFloat);
tst_mask = MaskLeastSignificant<uint32_t>(31);
out = WRegisterFrom(locations->Out());
}
MoveFPToInt(locations, is64bit, masm);
// Checks whether exponent bits are all 1 and fraction bits are all 0.
__ Eor(out, out, infinity);
// TST bitmask is used to mask out the sign bit: either 0x7fffffff or 0x7fffffffffffffff
// depending on is64bit.
__ Tst(out, tst_mask);
__ Cset(out, eq);
}
void IntrinsicLocationsBuilderARM64::VisitFloatIsInfinite(HInvoke* invoke) {
CreateFPToIntLocations(allocator_, invoke);
}
void IntrinsicCodeGeneratorARM64::VisitFloatIsInfinite(HInvoke* invoke) {
GenIsInfinite(invoke->GetLocations(), /* is64bit= */ false, GetVIXLAssembler());
}
void IntrinsicLocationsBuilderARM64::VisitDoubleIsInfinite(HInvoke* invoke) {
CreateFPToIntLocations(allocator_, invoke);
}
void IntrinsicCodeGeneratorARM64::VisitDoubleIsInfinite(HInvoke* invoke) {
GenIsInfinite(invoke->GetLocations(), /* is64bit= */ true, GetVIXLAssembler());
}
void IntrinsicLocationsBuilderARM64::VisitIntegerValueOf(HInvoke* invoke) {
InvokeRuntimeCallingConvention calling_convention;
IntrinsicVisitor::ComputeIntegerValueOfLocations(
invoke,
codegen_,
calling_convention.GetReturnLocation(DataType::Type::kReference),
Location::RegisterLocation(calling_convention.GetRegisterAt(0).GetCode()));
}
void IntrinsicCodeGeneratorARM64::VisitIntegerValueOf(HInvoke* invoke) {
IntrinsicVisitor::IntegerValueOfInfo info =
IntrinsicVisitor::ComputeIntegerValueOfInfo(invoke, codegen_->GetCompilerOptions());
LocationSummary* locations = invoke->GetLocations();
MacroAssembler* masm = GetVIXLAssembler();
Register out = RegisterFrom(locations->Out(), DataType::Type::kReference);
UseScratchRegisterScope temps(masm);
Register temp = temps.AcquireW();
auto allocate_instance = [&]() {
DCHECK(out.X().Is(InvokeRuntimeCallingConvention().GetRegisterAt(0)));
codegen_->LoadIntrinsicDeclaringClass(out, invoke);
codegen_->InvokeRuntime(kQuickAllocObjectInitialized, invoke, invoke->GetDexPc());
CheckEntrypointTypes<kQuickAllocObjectWithChecks, void*, mirror::Class*>();
};
if (invoke->InputAt(0)->IsConstant()) {
int32_t value = invoke->InputAt(0)->AsIntConstant()->GetValue();
if (static_cast<uint32_t>(value - info.low) < info.length) {
// Just embed the j.l.Integer in the code.
DCHECK_NE(info.value_boot_image_reference, IntegerValueOfInfo::kInvalidReference);
codegen_->LoadBootImageAddress(out, info.value_boot_image_reference);
} else {
DCHECK(locations->CanCall());
// Allocate and initialize a new j.l.Integer.
// TODO: If we JIT, we could allocate the j.l.Integer now, and store it in the
// JIT object table.
allocate_instance();
__ Mov(temp.W(), value);
__ Str(temp.W(), HeapOperand(out.W(), info.value_offset));
// Class pointer and `value` final field stores require a barrier before publication.
codegen_->GenerateMemoryBarrier(MemBarrierKind::kStoreStore);
}
} else {
DCHECK(locations->CanCall());
Register in = RegisterFrom(locations->InAt(0), DataType::Type::kInt32);
// Check bounds of our cache.
__ Add(out.W(), in.W(), -info.low);
__ Cmp(out.W(), info.length);
vixl::aarch64::Label allocate, done;
__ B(&allocate, hs);
// If the value is within the bounds, load the j.l.Integer directly from the array.
codegen_->LoadBootImageAddress(temp, info.array_data_boot_image_reference);
MemOperand source = HeapOperand(
temp, out.X(), LSL, DataType::SizeShift(DataType::Type::kReference));
codegen_->Load(DataType::Type::kReference, out, source);
codegen_->GetAssembler()->MaybeUnpoisonHeapReference(out);
__ B(&done);
__ Bind(&allocate);
// Otherwise allocate and initialize a new j.l.Integer.
allocate_instance();
__ Str(in.W(), HeapOperand(out.W(), info.value_offset));
// Class pointer and `value` final field stores require a barrier before publication.
codegen_->GenerateMemoryBarrier(MemBarrierKind::kStoreStore);
__ Bind(&done);
}
}
void IntrinsicLocationsBuilderARM64::VisitReferenceGetReferent(HInvoke* invoke) {
IntrinsicVisitor::CreateReferenceGetReferentLocations(invoke, codegen_);
if (kEmitCompilerReadBarrier && kUseBakerReadBarrier && invoke->GetLocations() != nullptr) {
invoke->GetLocations()->AddTemp(Location::RequiresRegister());
}
}
void IntrinsicCodeGeneratorARM64::VisitReferenceGetReferent(HInvoke* invoke) {
MacroAssembler* masm = GetVIXLAssembler();
LocationSummary* locations = invoke->GetLocations();
Location obj = locations->InAt(0);
Location out = locations->Out();
SlowPathCodeARM64* slow_path = new (GetAllocator()) IntrinsicSlowPathARM64(invoke);
codegen_->AddSlowPath(slow_path);
if (kEmitCompilerReadBarrier) {
// Check self->GetWeakRefAccessEnabled().
UseScratchRegisterScope temps(masm);
Register temp = temps.AcquireW();
__ Ldr(temp,
MemOperand(tr, Thread::WeakRefAccessEnabledOffset<kArm64PointerSize>().Uint32Value()));
__ Cbz(temp, slow_path->GetEntryLabel());
}
{
// Load the java.lang.ref.Reference class.
UseScratchRegisterScope temps(masm);
Register temp = temps.AcquireW();
codegen_->LoadIntrinsicDeclaringClass(temp, invoke);
// Check static fields java.lang.ref.Reference.{disableIntrinsic,slowPathEnabled} together.
MemberOffset disable_intrinsic_offset = IntrinsicVisitor::GetReferenceDisableIntrinsicOffset();
DCHECK_ALIGNED(disable_intrinsic_offset.Uint32Value(), 2u);
DCHECK_EQ(disable_intrinsic_offset.Uint32Value() + 1u,
IntrinsicVisitor::GetReferenceSlowPathEnabledOffset().Uint32Value());
__ Ldrh(temp, HeapOperand(temp, disable_intrinsic_offset.Uint32Value()));
__ Cbnz(temp, slow_path->GetEntryLabel());
}
// Load the value from the field.
uint32_t referent_offset = mirror::Reference::ReferentOffset().Uint32Value();
if (kEmitCompilerReadBarrier && kUseBakerReadBarrier) {
codegen_->GenerateFieldLoadWithBakerReadBarrier(invoke,
out,
WRegisterFrom(obj),
referent_offset,
/*maybe_temp=*/ locations->GetTemp(0),
/*needs_null_check=*/ true,
/*use_load_acquire=*/ true);
} else {
MemOperand field = HeapOperand(WRegisterFrom(obj), referent_offset);
codegen_->LoadAcquire(
invoke, DataType::Type::kReference, WRegisterFrom(out), field, /*needs_null_check=*/ true);
codegen_->MaybeGenerateReadBarrierSlow(invoke, out, out, obj, referent_offset);
}
__ Bind(slow_path->GetExitLabel());
}
void IntrinsicLocationsBuilderARM64::VisitReferenceRefersTo(HInvoke* invoke) {
IntrinsicVisitor::CreateReferenceRefersToLocations(invoke);
}
void IntrinsicCodeGeneratorARM64::VisitReferenceRefersTo(HInvoke* invoke) {
LocationSummary* locations = invoke->GetLocations();
MacroAssembler* masm = codegen_->GetVIXLAssembler();
UseScratchRegisterScope temps(masm);
Register obj = WRegisterFrom(locations->InAt(0));
Register other = WRegisterFrom(locations->InAt(1));
Register out = WRegisterFrom(locations->Out());
Register tmp = temps.AcquireW();
uint32_t referent_offset = mirror::Reference::ReferentOffset().Uint32Value();
uint32_t monitor_offset = mirror::Object::MonitorOffset().Int32Value();
MemOperand field = HeapOperand(obj, referent_offset);
codegen_->LoadAcquire(invoke, DataType::Type::kReference, tmp, field, /*needs_null_check=*/ true);
codegen_->GetAssembler()->MaybeUnpoisonHeapReference(tmp);
__ Cmp(tmp, other);
if (kEmitCompilerReadBarrier) {
DCHECK(kUseBakerReadBarrier);
vixl::aarch64::Label calculate_result;
// If the GC is not marking, the comparison result is final.
__ Cbz(mr, &calculate_result);
__ B(&calculate_result, eq); // ZF set if taken.
// Check if the loaded reference is null.
__ Cbz(tmp, &calculate_result); // ZF clear if taken.
// For correct memory visibility, we need a barrier before loading the lock word.
codegen_->GenerateMemoryBarrier(MemBarrierKind::kLoadAny);
// Load the lockword and check if it is a forwarding address.
static_assert(LockWord::kStateShift == 30u);
static_assert(LockWord::kStateForwardingAddress == 3u);
__ Ldr(tmp, HeapOperand(tmp, monitor_offset));
__ Cmp(tmp, Operand(0xc0000000));
__ B(&calculate_result, lo); // ZF clear if taken.
// Extract the forwarding address and compare with `other`.
__ Cmp(other, Operand(tmp, LSL, LockWord::kForwardingAddressShift));
__ Bind(&calculate_result);
}
// Convert ZF into the Boolean result.
__ Cset(out, eq);
}
void IntrinsicLocationsBuilderARM64::VisitThreadInterrupted(HInvoke* invoke) {
LocationSummary* locations =
new (allocator_) LocationSummary(invoke, LocationSummary::kNoCall, kIntrinsified);
locations->SetOut(Location::RequiresRegister());
}
void IntrinsicCodeGeneratorARM64::VisitThreadInterrupted(HInvoke* invoke) {
MacroAssembler* masm = GetVIXLAssembler();
Register out = RegisterFrom(invoke->GetLocations()->Out(), DataType::Type::kInt32);
UseScratchRegisterScope temps(masm);
Register temp = temps.AcquireX();
__ Add(temp, tr, Thread::InterruptedOffset<kArm64PointerSize>().Int32Value());
__ Ldar(out.W(), MemOperand(temp));
vixl::aarch64::Label done;
__ Cbz(out.W(), &done);
__ Stlr(wzr, MemOperand(temp));
__ Bind(&done);
}
void IntrinsicLocationsBuilderARM64::VisitReachabilityFence(HInvoke* invoke) {
LocationSummary* locations =
new (allocator_) LocationSummary(invoke, LocationSummary::kNoCall, kIntrinsified);
locations->SetInAt(0, Location::Any());
}
void IntrinsicCodeGeneratorARM64::VisitReachabilityFence(HInvoke* invoke ATTRIBUTE_UNUSED) { }
void IntrinsicLocationsBuilderARM64::VisitCRC32Update(HInvoke* invoke) {
if (!codegen_->GetInstructionSetFeatures().HasCRC()) {
return;
}
LocationSummary* locations = new (allocator_) LocationSummary(invoke,
LocationSummary::kNoCall,
kIntrinsified);
locations->SetInAt(0, Location::RequiresRegister());
locations->SetInAt(1, Location::RequiresRegister());
locations->SetOut(Location::RequiresRegister(), Location::kNoOutputOverlap);
}
// Lower the invoke of CRC32.update(int crc, int b).
void IntrinsicCodeGeneratorARM64::VisitCRC32Update(HInvoke* invoke) {
DCHECK(codegen_->GetInstructionSetFeatures().HasCRC());
MacroAssembler* masm = GetVIXLAssembler();
Register crc = InputRegisterAt(invoke, 0);
Register val = InputRegisterAt(invoke, 1);
Register out = OutputRegister(invoke);
// The general algorithm of the CRC32 calculation is:
// crc = ~crc
// result = crc32_for_byte(crc, b)
// crc = ~result
// It is directly lowered to three instructions.
UseScratchRegisterScope temps(masm);
Register tmp = temps.AcquireSameSizeAs(out);
__ Mvn(tmp, crc);
__ Crc32b(tmp, tmp, val);
__ Mvn(out, tmp);
}
// Generate code using CRC32 instructions which calculates
// a CRC32 value of a byte.
//
// Parameters:
// masm - VIXL macro assembler
// crc - a register holding an initial CRC value
// ptr - a register holding a memory address of bytes
// length - a register holding a number of bytes to process
// out - a register to put a result of calculation
static void GenerateCodeForCalculationCRC32ValueOfBytes(MacroAssembler* masm,
const Register& crc,
const Register& ptr,
const Register& length,
const Register& out) {
// The algorithm of CRC32 of bytes is:
// crc = ~crc
// process a few first bytes to make the array 8-byte aligned
// while array has 8 bytes do:
// crc = crc32_of_8bytes(crc, 8_bytes(array))
// if array has 4 bytes:
// crc = crc32_of_4bytes(crc, 4_bytes(array))
// if array has 2 bytes:
// crc = crc32_of_2bytes(crc, 2_bytes(array))
// if array has a byte:
// crc = crc32_of_byte(crc, 1_byte(array))
// crc = ~crc
vixl::aarch64::Label loop, done;
vixl::aarch64::Label process_4bytes, process_2bytes, process_1byte;
vixl::aarch64::Label aligned2, aligned4, aligned8;
// Use VIXL scratch registers as the VIXL macro assembler won't use them in
// instructions below.
UseScratchRegisterScope temps(masm);
Register len = temps.AcquireW();
Register array_elem = temps.AcquireW();
__ Mvn(out, crc);
__ Mov(len, length);
__ Tbz(ptr, 0, &aligned2);
__ Subs(len, len, 1);
__ B(&done, lo);
__ Ldrb(array_elem, MemOperand(ptr, 1, PostIndex));
__ Crc32b(out, out, array_elem);
__ Bind(&aligned2);
__ Tbz(ptr, 1, &aligned4);
__ Subs(len, len, 2);
__ B(&process_1byte, lo);
__ Ldrh(array_elem, MemOperand(ptr, 2, PostIndex));
__ Crc32h(out, out, array_elem);
__ Bind(&aligned4);
__ Tbz(ptr, 2, &aligned8);
__ Subs(len, len, 4);
__ B(&process_2bytes, lo);
__ Ldr(array_elem, MemOperand(ptr, 4, PostIndex));
__ Crc32w(out, out, array_elem);
__ Bind(&aligned8);
__ Subs(len, len, 8);
// If len < 8 go to process data by 4 bytes, 2 bytes and a byte.
__ B(&process_4bytes, lo);
// The main loop processing data by 8 bytes.
__ Bind(&loop);
__ Ldr(array_elem.X(), MemOperand(ptr, 8, PostIndex));
__ Subs(len, len, 8);
__ Crc32x(out, out, array_elem.X());
// if len >= 8, process the next 8 bytes.
__ B(&loop, hs);
// Process the data which is less than 8 bytes.
// The code generated below works with values of len
// which come in the range [-8, 0].
// The first three bits are used to detect whether 4 bytes or 2 bytes or
// a byte can be processed.
// The checking order is from bit 2 to bit 0:
// bit 2 is set: at least 4 bytes available
// bit 1 is set: at least 2 bytes available
// bit 0 is set: at least a byte available
__ Bind(&process_4bytes);
// Goto process_2bytes if less than four bytes available
__ Tbz(len, 2, &process_2bytes);
__ Ldr(array_elem, MemOperand(ptr, 4, PostIndex));
__ Crc32w(out, out, array_elem);
__ Bind(&process_2bytes);
// Goto process_1bytes if less than two bytes available
__ Tbz(len, 1, &process_1byte);
__ Ldrh(array_elem, MemOperand(ptr, 2, PostIndex));
__ Crc32h(out, out, array_elem);
__ Bind(&process_1byte);
// Goto done if no bytes available
__ Tbz(len, 0, &done);
__ Ldrb(array_elem, MemOperand(ptr));
__ Crc32b(out, out, array_elem);
__ Bind(&done);
__ Mvn(out, out);
}
// The threshold for sizes of arrays to use the library provided implementation
// of CRC32.updateBytes instead of the intrinsic.
static constexpr int32_t kCRC32UpdateBytesThreshold = 64 * 1024;
void IntrinsicLocationsBuilderARM64::VisitCRC32UpdateBytes(HInvoke* invoke) {
if (!codegen_->GetInstructionSetFeatures().HasCRC()) {
return;
}
LocationSummary* locations =
new (allocator_) LocationSummary(invoke,
LocationSummary::kCallOnSlowPath,
kIntrinsified);
locations->SetInAt(0, Location::RequiresRegister());
locations->SetInAt(1, Location::RequiresRegister());
locations->SetInAt(2, Location::RegisterOrConstant(invoke->InputAt(2)));
locations->SetInAt(3, Location::RequiresRegister());
locations->AddTemp(Location::RequiresRegister());
locations->SetOut(Location::RequiresRegister());
}
// Lower the invoke of CRC32.updateBytes(int crc, byte[] b, int off, int len)
//
// Note: The intrinsic is not used if len exceeds a threshold.
void IntrinsicCodeGeneratorARM64::VisitCRC32UpdateBytes(HInvoke* invoke) {
DCHECK(codegen_->GetInstructionSetFeatures().HasCRC());
MacroAssembler* masm = GetVIXLAssembler();
LocationSummary* locations = invoke->GetLocations();
SlowPathCodeARM64* slow_path =
new (codegen_->GetScopedAllocator()) IntrinsicSlowPathARM64(invoke);
codegen_->AddSlowPath(slow_path);
Register length = WRegisterFrom(locations->InAt(3));
__ Cmp(length, kCRC32UpdateBytesThreshold);
__ B(slow_path->GetEntryLabel(), hi);
const uint32_t array_data_offset =
mirror::Array::DataOffset(Primitive::kPrimByte).Uint32Value();
Register ptr = XRegisterFrom(locations->GetTemp(0));
Register array = XRegisterFrom(locations->InAt(1));
Location offset = locations->InAt(2);
if (offset.IsConstant()) {
int32_t offset_value = offset.GetConstant()->AsIntConstant()->GetValue();
__ Add(ptr, array, array_data_offset + offset_value);
} else {
__ Add(ptr, array, array_data_offset);
__ Add(ptr, ptr, XRegisterFrom(offset));
}
Register crc = WRegisterFrom(locations->InAt(0));
Register out = WRegisterFrom(locations->Out());
GenerateCodeForCalculationCRC32ValueOfBytes(masm, crc, ptr, length, out);
__ Bind(slow_path->GetExitLabel());
}
void IntrinsicLocationsBuilderARM64::VisitCRC32UpdateByteBuffer(HInvoke* invoke) {
if (!codegen_->GetInstructionSetFeatures().HasCRC()) {
return;
}
LocationSummary* locations =
new (allocator_) LocationSummary(invoke,
LocationSummary::kNoCall,
kIntrinsified);
locations->SetInAt(0, Location::RequiresRegister());
locations->SetInAt(1, Location::RequiresRegister());
locations->SetInAt(2, Location::RequiresRegister());
locations->SetInAt(3, Location::RequiresRegister());
locations->AddTemp(Location::RequiresRegister());
locations->SetOut(Location::RequiresRegister());
}
// Lower the invoke of CRC32.updateByteBuffer(int crc, long addr, int off, int len)
//
// There is no need to generate code checking if addr is 0.
// The method updateByteBuffer is a private method of java.util.zip.CRC32.
// This guarantees no calls outside of the CRC32 class.
// An address of DirectBuffer is always passed to the call of updateByteBuffer.
// It might be an implementation of an empty DirectBuffer which can use a zero
// address but it must have the length to be zero. The current generated code
// correctly works with the zero length.
void IntrinsicCodeGeneratorARM64::VisitCRC32UpdateByteBuffer(HInvoke* invoke) {
DCHECK(codegen_->GetInstructionSetFeatures().HasCRC());
MacroAssembler* masm = GetVIXLAssembler();
LocationSummary* locations = invoke->GetLocations();
Register addr = XRegisterFrom(locations->InAt(1));
Register ptr = XRegisterFrom(locations->GetTemp(0));
__ Add(ptr, addr, XRegisterFrom(locations->InAt(2)));
Register crc = WRegisterFrom(locations->InAt(0));
Register length = WRegisterFrom(locations->InAt(3));
Register out = WRegisterFrom(locations->Out());
GenerateCodeForCalculationCRC32ValueOfBytes(masm, crc, ptr, length, out);
}
void IntrinsicLocationsBuilderARM64::VisitFP16ToFloat(HInvoke* invoke) {
if (!codegen_->GetInstructionSetFeatures().HasFP16()) {
return;
}
LocationSummary* locations = new (allocator_) LocationSummary(invoke,
LocationSummary::kNoCall,
kIntrinsified);
locations->SetInAt(0, Location::RequiresRegister());
locations->SetOut(Location::RequiresFpuRegister());
}
void IntrinsicCodeGeneratorARM64::VisitFP16ToFloat(HInvoke* invoke) {
DCHECK(codegen_->GetInstructionSetFeatures().HasFP16());
MacroAssembler* masm = GetVIXLAssembler();
UseScratchRegisterScope scratch_scope(masm);
Register bits = InputRegisterAt(invoke, 0);
VRegister out = SRegisterFrom(invoke->GetLocations()->Out());
VRegister half = scratch_scope.AcquireH();
__ Fmov(half, bits); // ARMv8.2
__ Fcvt(out, half);
}
void IntrinsicLocationsBuilderARM64::VisitFP16ToHalf(HInvoke* invoke) {
if (!codegen_->GetInstructionSetFeatures().HasFP16()) {
return;
}
LocationSummary* locations = new (allocator_) LocationSummary(invoke,
LocationSummary::kNoCall,
kIntrinsified);
locations->SetInAt(0, Location::RequiresFpuRegister());
locations->SetOut(Location::RequiresRegister());
}
void IntrinsicCodeGeneratorARM64::VisitFP16ToHalf(HInvoke* invoke) {
DCHECK(codegen_->GetInstructionSetFeatures().HasFP16());
MacroAssembler* masm = GetVIXLAssembler();
UseScratchRegisterScope scratch_scope(masm);
VRegister in = SRegisterFrom(invoke->GetLocations()->InAt(0));
VRegister half = scratch_scope.AcquireH();
Register out = WRegisterFrom(invoke->GetLocations()->Out());
__ Fcvt(half, in);
__ Fmov(out, half);
__ Sxth(out, out); // sign extend due to returning a short type.
}
template<typename OP>
void GenerateFP16Round(HInvoke* invoke,
CodeGeneratorARM64* const codegen_,
MacroAssembler* masm,
const OP roundOp) {
DCHECK(codegen_->GetInstructionSetFeatures().HasFP16());
LocationSummary* locations = invoke->GetLocations();
UseScratchRegisterScope scratch_scope(masm);
Register out = WRegisterFrom(locations->Out());
VRegister half = scratch_scope.AcquireH();
__ Fmov(half, WRegisterFrom(locations->InAt(0)));
roundOp(half, half);
__ Fmov(out, half);
__ Sxth(out, out);
}
void IntrinsicLocationsBuilderARM64::VisitFP16Floor(HInvoke* invoke) {
if (!codegen_->GetInstructionSetFeatures().HasFP16()) {
return;
}
CreateIntToIntLocations(allocator_, invoke);
}
void IntrinsicCodeGeneratorARM64::VisitFP16Floor(HInvoke* invoke) {
MacroAssembler* masm = GetVIXLAssembler();
auto roundOp = [masm](const VRegister& out, const VRegister& in) {
__ Frintm(out, in); // Round towards Minus infinity
};
GenerateFP16Round(invoke, codegen_, masm, roundOp);
}
void IntrinsicLocationsBuilderARM64::VisitFP16Ceil(HInvoke* invoke) {
if (!codegen_->GetInstructionSetFeatures().HasFP16()) {
return;
}
CreateIntToIntLocations(allocator_, invoke);
}
void IntrinsicCodeGeneratorARM64::VisitFP16Ceil(HInvoke* invoke) {
MacroAssembler* masm = GetVIXLAssembler();
auto roundOp = [masm](const VRegister& out, const VRegister& in) {
__ Frintp(out, in); // Round towards Plus infinity
};
GenerateFP16Round(invoke, codegen_, masm, roundOp);
}
void IntrinsicLocationsBuilderARM64::VisitFP16Rint(HInvoke* invoke) {
if (!codegen_->GetInstructionSetFeatures().HasFP16()) {
return;
}
CreateIntToIntLocations(allocator_, invoke);
}
void IntrinsicCodeGeneratorARM64::VisitFP16Rint(HInvoke* invoke) {
MacroAssembler* masm = GetVIXLAssembler();
auto roundOp = [masm](const VRegister& out, const VRegister& in) {
__ Frintn(out, in); // Round to nearest, with ties to even
};
GenerateFP16Round(invoke, codegen_, masm, roundOp);
}
template<typename OP>
void GenerateFP16Compare(HInvoke* invoke,
CodeGeneratorARM64* codegen,
MacroAssembler* masm,
const OP compareOp) {
DCHECK(codegen->GetInstructionSetFeatures().HasFP16());
LocationSummary* locations = invoke->GetLocations();
Register out = WRegisterFrom(locations->Out());
VRegister half0 = HRegisterFrom(locations->GetTemp(0));
VRegister half1 = HRegisterFrom(locations->GetTemp(1));
__ Fmov(half0, WRegisterFrom(locations->InAt(0)));
__ Fmov(half1, WRegisterFrom(locations->InAt(1)));
compareOp(out, half0, half1);
}
static inline void GenerateFP16Compare(HInvoke* invoke,
CodeGeneratorARM64* codegen,
MacroAssembler* masm,
vixl::aarch64::Condition cond) {
auto compareOp = [masm, cond](const Register out, const VRegister& in0, const VRegister& in1) {
__ Fcmp(in0, in1);
__ Cset(out, cond);
};
GenerateFP16Compare(invoke, codegen, masm, compareOp);
}
void IntrinsicLocationsBuilderARM64::VisitFP16Greater(HInvoke* invoke) {
if (!codegen_->GetInstructionSetFeatures().HasFP16()) {
return;
}
CreateIntIntToIntLocations(allocator_, invoke);
invoke->GetLocations()->AddTemp(Location::RequiresFpuRegister());
invoke->GetLocations()->AddTemp(Location::RequiresFpuRegister());
}
void IntrinsicCodeGeneratorARM64::VisitFP16Greater(HInvoke* invoke) {
MacroAssembler* masm = GetVIXLAssembler();
GenerateFP16Compare(invoke, codegen_, masm, gt);
}
void IntrinsicLocationsBuilderARM64::VisitFP16GreaterEquals(HInvoke* invoke) {
if (!codegen_->GetInstructionSetFeatures().HasFP16()) {
return;
}
CreateIntIntToIntLocations(allocator_, invoke);
invoke->GetLocations()->AddTemp(Location::RequiresFpuRegister());
invoke->GetLocations()->AddTemp(Location::RequiresFpuRegister());
}
void IntrinsicCodeGeneratorARM64::VisitFP16GreaterEquals(HInvoke* invoke) {
MacroAssembler* masm = GetVIXLAssembler();
GenerateFP16Compare(invoke, codegen_, masm, ge);
}
void IntrinsicLocationsBuilderARM64::VisitFP16Less(HInvoke* invoke) {
if (!codegen_->GetInstructionSetFeatures().HasFP16()) {
return;
}
CreateIntIntToIntLocations(allocator_, invoke);
invoke->GetLocations()->AddTemp(Location::RequiresFpuRegister());
invoke->GetLocations()->AddTemp(Location::RequiresFpuRegister());
}
void IntrinsicCodeGeneratorARM64::VisitFP16Less(HInvoke* invoke) {
MacroAssembler* masm = GetVIXLAssembler();
GenerateFP16Compare(invoke, codegen_, masm, mi);
}
void IntrinsicLocationsBuilderARM64::VisitFP16LessEquals(HInvoke* invoke) {
if (!codegen_->GetInstructionSetFeatures().HasFP16()) {
return;
}
CreateIntIntToIntLocations(allocator_, invoke);
invoke->GetLocations()->AddTemp(Location::RequiresFpuRegister());
invoke->GetLocations()->AddTemp(Location::RequiresFpuRegister());
}
void IntrinsicCodeGeneratorARM64::VisitFP16LessEquals(HInvoke* invoke) {
MacroAssembler* masm = GetVIXLAssembler();
GenerateFP16Compare(invoke, codegen_, masm, ls);
}
static void GenerateDivideUnsigned(HInvoke* invoke, CodeGeneratorARM64* codegen) {
LocationSummary* locations = invoke->GetLocations();
MacroAssembler* masm = codegen->GetVIXLAssembler();
DataType::Type type = invoke->GetType();
DCHECK(type == DataType::Type::kInt32 || type == DataType::Type::kInt64);
Register dividend = RegisterFrom(locations->InAt(0), type);
Register divisor = RegisterFrom(locations->InAt(1), type);
Register out = RegisterFrom(locations->Out(), type);
// Check if divisor is zero, bail to managed implementation to handle.
SlowPathCodeARM64* slow_path =
new (codegen->GetScopedAllocator()) IntrinsicSlowPathARM64(invoke);
codegen->AddSlowPath(slow_path);
__ Cbz(divisor, slow_path->GetEntryLabel());
__ Udiv(out, dividend, divisor);
__ Bind(slow_path->GetExitLabel());
}
void IntrinsicLocationsBuilderARM64::VisitIntegerDivideUnsigned(HInvoke* invoke) {
CreateIntIntToIntSlowPathCallLocations(allocator_, invoke);
}
void IntrinsicCodeGeneratorARM64::VisitIntegerDivideUnsigned(HInvoke* invoke) {
GenerateDivideUnsigned(invoke, codegen_);
}
void IntrinsicLocationsBuilderARM64::VisitLongDivideUnsigned(HInvoke* invoke) {
CreateIntIntToIntSlowPathCallLocations(allocator_, invoke);
}
void IntrinsicCodeGeneratorARM64::VisitLongDivideUnsigned(HInvoke* invoke) {
GenerateDivideUnsigned(invoke, codegen_);
}
void IntrinsicLocationsBuilderARM64::VisitMathMultiplyHigh(HInvoke* invoke) {
CreateIntIntToIntLocations(allocator_, invoke);
}
void IntrinsicCodeGeneratorARM64::VisitMathMultiplyHigh(HInvoke* invoke) {
LocationSummary* locations = invoke->GetLocations();
MacroAssembler* masm = codegen_->GetVIXLAssembler();
DataType::Type type = invoke->GetType();
DCHECK(type == DataType::Type::kInt64);
Register x = RegisterFrom(locations->InAt(0), type);
Register y = RegisterFrom(locations->InAt(1), type);
Register out = RegisterFrom(locations->Out(), type);
__ Smulh(out, x, y);
}
class VarHandleSlowPathARM64 : public IntrinsicSlowPathARM64 {
public:
VarHandleSlowPathARM64(HInvoke* invoke, std::memory_order order)
: IntrinsicSlowPathARM64(invoke),
order_(order),
return_success_(false),
strong_(false),
get_and_update_op_(GetAndUpdateOp::kAdd) {
}
vixl::aarch64::Label* GetByteArrayViewCheckLabel() {
return &byte_array_view_check_label_;
}
vixl::aarch64::Label* GetNativeByteOrderLabel() {
return &native_byte_order_label_;
}
void SetCompareAndSetOrExchangeArgs(bool return_success, bool strong) {
if (return_success) {
DCHECK(GetAccessModeTemplate() == mirror::VarHandle::AccessModeTemplate::kCompareAndSet);
} else {
DCHECK(GetAccessModeTemplate() == mirror::VarHandle::AccessModeTemplate::kCompareAndExchange);
}
return_success_ = return_success;
strong_ = strong;
}
void SetGetAndUpdateOp(GetAndUpdateOp get_and_update_op) {
DCHECK(GetAccessModeTemplate() == mirror::VarHandle::AccessModeTemplate::kGetAndUpdate);
get_and_update_op_ = get_and_update_op;
}
void EmitNativeCode(CodeGenerator* codegen_in) override {
if (GetByteArrayViewCheckLabel()->IsLinked()) {
EmitByteArrayViewCode(codegen_in);
}
IntrinsicSlowPathARM64::EmitNativeCode(codegen_in);
}
private:
HInvoke* GetInvoke() const {
return GetInstruction()->AsInvoke();
}
mirror::VarHandle::AccessModeTemplate GetAccessModeTemplate() const {
return mirror::VarHandle::GetAccessModeTemplateByIntrinsic(GetInvoke()->GetIntrinsic());
}
void EmitByteArrayViewCode(CodeGenerator* codegen_in);
vixl::aarch64::Label byte_array_view_check_label_;
vixl::aarch64::Label native_byte_order_label_;
// Shared parameter for all VarHandle intrinsics.
std::memory_order order_;
// Extra arguments for GenerateVarHandleCompareAndSetOrExchange().
bool return_success_;
bool strong_;
// Extra argument for GenerateVarHandleGetAndUpdate().
GetAndUpdateOp get_and_update_op_;
};
// Generate subtype check without read barriers.
static void GenerateSubTypeObjectCheckNoReadBarrier(CodeGeneratorARM64* codegen,
SlowPathCodeARM64* slow_path,
Register object,
Register type,
bool object_can_be_null = true) {
MacroAssembler* masm = codegen->GetVIXLAssembler();
const MemberOffset class_offset = mirror::Object::ClassOffset();
const MemberOffset super_class_offset = mirror::Class::SuperClassOffset();
vixl::aarch64::Label success;
if (object_can_be_null) {
__ Cbz(object, &success);
}
UseScratchRegisterScope temps(masm);
Register temp = temps.AcquireW();
__ Ldr(temp, HeapOperand(object, class_offset.Int32Value()));
codegen->GetAssembler()->MaybeUnpoisonHeapReference(temp);
vixl::aarch64::Label loop;
__ Bind(&loop);
__ Cmp(type, temp);
__ B(&success, eq);
__ Ldr(temp, HeapOperand(temp, super_class_offset.Int32Value()));
codegen->GetAssembler()->MaybeUnpoisonHeapReference(temp);
__ Cbz(temp, slow_path->GetEntryLabel());
__ B(&loop);
__ Bind(&success);
}
// Check access mode and the primitive type from VarHandle.varType.
// Check reference arguments against the VarHandle.varType; for references this is a subclass
// check without read barrier, so it can have false negatives which we handle in the slow path.
static void GenerateVarHandleAccessModeAndVarTypeChecks(HInvoke* invoke,
CodeGeneratorARM64* codegen,
SlowPathCodeARM64* slow_path,
DataType::Type type) {
mirror::VarHandle::AccessMode access_mode =
mirror::VarHandle::GetAccessModeByIntrinsic(invoke->GetIntrinsic());
Primitive::Type primitive_type = DataTypeToPrimitive(type);
MacroAssembler* masm = codegen->GetVIXLAssembler();
Register varhandle = InputRegisterAt(invoke, 0);
const MemberOffset var_type_offset = mirror::VarHandle::VarTypeOffset();
const MemberOffset access_mode_bit_mask_offset = mirror::VarHandle::AccessModesBitMaskOffset();
const MemberOffset primitive_type_offset = mirror::Class::PrimitiveTypeOffset();
UseScratchRegisterScope temps(masm);
Register var_type_no_rb = temps.AcquireW();
Register temp2 = temps.AcquireW();
// Check that the operation is permitted and the primitive type of varhandle.varType.
// We do not need a read barrier when loading a reference only for loading constant
// primitive field through the reference. Use LDP to load the fields together.
DCHECK_EQ(var_type_offset.Int32Value() + 4, access_mode_bit_mask_offset.Int32Value());
__ Ldp(var_type_no_rb, temp2, HeapOperand(varhandle, var_type_offset.Int32Value()));
codegen->GetAssembler()->MaybeUnpoisonHeapReference(var_type_no_rb);
__ Tbz(temp2, static_cast<uint32_t>(access_mode), slow_path->GetEntryLabel());
__ Ldrh(temp2, HeapOperand(var_type_no_rb, primitive_type_offset.Int32Value()));
if (primitive_type == Primitive::kPrimNot) {
static_assert(Primitive::kPrimNot == 0);
__ Cbnz(temp2, slow_path->GetEntryLabel());
} else {
__ Cmp(temp2, static_cast<uint16_t>(primitive_type));
__ B(slow_path->GetEntryLabel(), ne);
}
temps.Release(temp2);
if (type == DataType::Type::kReference) {
// Check reference arguments against the varType.
// False negatives due to varType being an interface or array type
// or due to the missing read barrier are handled by the slow path.
size_t expected_coordinates_count = GetExpectedVarHandleCoordinatesCount(invoke);
uint32_t arguments_start = /* VarHandle object */ 1u + expected_coordinates_count;
uint32_t number_of_arguments = invoke->GetNumberOfArguments();
for (size_t arg_index = arguments_start; arg_index != number_of_arguments; ++arg_index) {
HInstruction* arg = invoke->InputAt(arg_index);
DCHECK_EQ(arg->GetType(), DataType::Type::kReference);
if (!arg->IsNullConstant()) {
Register arg_reg = WRegisterFrom(invoke->GetLocations()->InAt(arg_index));
GenerateSubTypeObjectCheckNoReadBarrier(codegen, slow_path, arg_reg, var_type_no_rb);
}
}
}
}
static void GenerateVarHandleStaticFieldCheck(HInvoke* invoke,
CodeGeneratorARM64* codegen,
SlowPathCodeARM64* slow_path) {
MacroAssembler* masm = codegen->GetVIXLAssembler();
Register varhandle = InputRegisterAt(invoke, 0);
const MemberOffset coordinate_type0_offset = mirror::VarHandle::CoordinateType0Offset();
UseScratchRegisterScope temps(masm);
Register temp = temps.AcquireW();
// Check that the VarHandle references a static field by checking that coordinateType0 == null.
// Do not emit read barrier (or unpoison the reference) for comparing to null.
__ Ldr(temp, HeapOperand(varhandle, coordinate_type0_offset.Int32Value()));
__ Cbnz(temp, slow_path->GetEntryLabel());
}
static void GenerateVarHandleInstanceFieldChecks(HInvoke* invoke,
CodeGeneratorARM64* codegen,
SlowPathCodeARM64* slow_path) {
MacroAssembler* masm = codegen->GetVIXLAssembler();
Register varhandle = InputRegisterAt(invoke, 0);
Register object = InputRegisterAt(invoke, 1);
const MemberOffset coordinate_type0_offset = mirror::VarHandle::CoordinateType0Offset();
const MemberOffset coordinate_type1_offset = mirror::VarHandle::CoordinateType1Offset();
// Null-check the object.
__ Cbz(object, slow_path->GetEntryLabel());
UseScratchRegisterScope temps(masm);
Register temp = temps.AcquireW();
Register temp2 = temps.AcquireW();
// Check that the VarHandle references an instance field by checking that
// coordinateType1 == null. coordinateType0 should not be null, but this is handled by the
// type compatibility check with the source object's type, which will fail for null.
DCHECK_EQ(coordinate_type0_offset.Int32Value() + 4, coordinate_type1_offset.Int32Value());
__ Ldp(temp, temp2, HeapOperand(varhandle, coordinate_type0_offset.Int32Value()));
codegen->GetAssembler()->MaybeUnpoisonHeapReference(temp);
// No need for read barrier or unpoisoning of coordinateType1 for comparison with null.
__ Cbnz(temp2, slow_path->GetEntryLabel());
// Check that the object has the correct type.
// We deliberately avoid the read barrier, letting the slow path handle the false negatives.
temps.Release(temp2); // Needed by GenerateSubTypeObjectCheckNoReadBarrier().
GenerateSubTypeObjectCheckNoReadBarrier(
codegen, slow_path, object, temp, /*object_can_be_null=*/ false);
}
static DataType::Type GetVarHandleExpectedValueType(HInvoke* invoke,
size_t expected_coordinates_count) {
DCHECK_EQ(expected_coordinates_count, GetExpectedVarHandleCoordinatesCount(invoke));
uint32_t number_of_arguments = invoke->GetNumberOfArguments();
DCHECK_GE(number_of_arguments, /* VarHandle object */ 1u + expected_coordinates_count);
if (number_of_arguments == /* VarHandle object */ 1u + expected_coordinates_count) {
return invoke->GetType();
} else {
return GetDataTypeFromShorty(invoke, number_of_arguments - 1u);
}
}
static void GenerateVarHandleArrayChecks(HInvoke* invoke,
CodeGeneratorARM64* codegen,
VarHandleSlowPathARM64* slow_path) {
MacroAssembler* masm = codegen->GetVIXLAssembler();
Register varhandle = InputRegisterAt(invoke, 0);
Register object = InputRegisterAt(invoke, 1);
Register index = InputRegisterAt(invoke, 2);
DataType::Type value_type =
GetVarHandleExpectedValueType(invoke, /*expected_coordinates_count=*/ 2u);
Primitive::Type primitive_type = DataTypeToPrimitive(value_type);
const MemberOffset coordinate_type0_offset = mirror::VarHandle::CoordinateType0Offset();
const MemberOffset coordinate_type1_offset = mirror::VarHandle::CoordinateType1Offset();
const MemberOffset component_type_offset = mirror::Class::ComponentTypeOffset();
const MemberOffset primitive_type_offset = mirror::Class::PrimitiveTypeOffset();
const MemberOffset class_offset = mirror::Object::ClassOffset();
const MemberOffset array_length_offset = mirror::Array::LengthOffset();
// Null-check the object.
__ Cbz(object, slow_path->GetEntryLabel());
UseScratchRegisterScope temps(masm);
Register temp = temps.AcquireW();
Register temp2 = temps.AcquireW();
// Check that the VarHandle references an array, byte array view or ByteBuffer by checking
// that coordinateType1 != null. If that's true, coordinateType1 shall be int.class and
// coordinateType0 shall not be null but we do not explicitly verify that.
DCHECK_EQ(coordinate_type0_offset.Int32Value() + 4, coordinate_type1_offset.Int32Value());
__ Ldp(temp, temp2, HeapOperand(varhandle, coordinate_type0_offset.Int32Value()));
codegen->GetAssembler()->MaybeUnpoisonHeapReference(temp);
// No need for read barrier or unpoisoning of coordinateType1 for comparison with null.
__ Cbz(temp2, slow_path->GetEntryLabel());
// Check object class against componentType0.
//
// This is an exact check and we defer other cases to the runtime. This includes
// conversion to array of superclass references, which is valid but subsequently
// requires all update operations to check that the value can indeed be stored.
// We do not want to perform such extra checks in the intrinsified code.
//
// We do this check without read barrier, so there can be false negatives which we
// defer to the slow path. There shall be no false negatives for array classes in the
// boot image (including Object[] and primitive arrays) because they are non-movable.
__ Ldr(temp2, HeapOperand(object, class_offset.Int32Value()));
codegen->GetAssembler()->MaybeUnpoisonHeapReference(temp2);
__ Cmp(temp, temp2);
__ B(slow_path->GetEntryLabel(), ne);
// Check that the coordinateType0 is an array type. We do not need a read barrier
// for loading constant reference fields (or chains of them) for comparison with null,
// nor for finally loading a constant primitive field (primitive type) below.
__ Ldr(temp2, HeapOperand(temp, component_type_offset.Int32Value()));
codegen->GetAssembler()->MaybeUnpoisonHeapReference(temp2);
__ Cbz(temp2, slow_path->GetEntryLabel());
// Check that the array component type matches the primitive type.
__ Ldrh(temp2, HeapOperand(temp2, primitive_type_offset.Int32Value()));
if (primitive_type == Primitive::kPrimNot) {
static_assert(Primitive::kPrimNot == 0);
__ Cbnz(temp2, slow_path->GetEntryLabel());
} else {
// With the exception of `kPrimNot` (handled above), `kPrimByte` and `kPrimBoolean`,
// we shall check for a byte array view in the slow path.
// The check requires the ByteArrayViewVarHandle.class to be in the boot image,
// so we cannot emit that if we're JITting without boot image.
bool boot_image_available =
codegen->GetCompilerOptions().IsBootImage() ||
!Runtime::Current()->GetHeap()->GetBootImageSpaces().empty();
DCHECK(boot_image_available || codegen->GetCompilerOptions().IsJitCompiler());
size_t can_be_view = (DataType::Size(value_type) != 1u) && boot_image_available;
vixl::aarch64::Label* slow_path_label =
can_be_view ? slow_path->GetByteArrayViewCheckLabel() : slow_path->GetEntryLabel();
__ Cmp(temp2, static_cast<uint16_t>(primitive_type));
__ B(slow_path_label, ne);
}
// Check for array index out of bounds.
__ Ldr(temp, HeapOperand(object, array_length_offset.Int32Value()));
__ Cmp(index, temp);
__ B(slow_path->GetEntryLabel(), hs);
}
static void GenerateVarHandleCoordinateChecks(HInvoke* invoke,
CodeGeneratorARM64* codegen,
VarHandleSlowPathARM64* slow_path) {
size_t expected_coordinates_count = GetExpectedVarHandleCoordinatesCount(invoke);
if (expected_coordinates_count == 0u) {
GenerateVarHandleStaticFieldCheck(invoke, codegen, slow_path);
} else if (expected_coordinates_count == 1u) {
GenerateVarHandleInstanceFieldChecks(invoke, codegen, slow_path);
} else {
DCHECK_EQ(expected_coordinates_count, 2u);
GenerateVarHandleArrayChecks(invoke, codegen, slow_path);
}
}
static VarHandleSlowPathARM64* GenerateVarHandleChecks(HInvoke* invoke,
CodeGeneratorARM64* codegen,
std::memory_order order,
DataType::Type type) {
VarHandleSlowPathARM64* slow_path =
new (codegen->GetScopedAllocator()) VarHandleSlowPathARM64(invoke, order);
codegen->AddSlowPath(slow_path);
GenerateVarHandleAccessModeAndVarTypeChecks(invoke, codegen, slow_path, type);
GenerateVarHandleCoordinateChecks(invoke, codegen, slow_path);
return slow_path;
}
struct VarHandleTarget {
Register object; // The object holding the value to operate on.
Register offset; // The offset of the value to operate on.
};
static VarHandleTarget GetVarHandleTarget(HInvoke* invoke) {
size_t expected_coordinates_count = GetExpectedVarHandleCoordinatesCount(invoke);
LocationSummary* locations = invoke->GetLocations();
VarHandleTarget target;
// The temporary allocated for loading the offset.
target.offset = WRegisterFrom(locations->GetTemp(0u));
// The reference to the object that holds the value to operate on.
target.object = (expected_coordinates_count == 0u)
? WRegisterFrom(locations->GetTemp(1u))
: InputRegisterAt(invoke, 1);
return target;
}
static void GenerateVarHandleTarget(HInvoke* invoke,
const VarHandleTarget& target,
CodeGeneratorARM64* codegen) {
MacroAssembler* masm = codegen->GetVIXLAssembler();
Register varhandle = InputRegisterAt(invoke, 0);
size_t expected_coordinates_count = GetExpectedVarHandleCoordinatesCount(invoke);
if (expected_coordinates_count <= 1u) {
// For static fields, we need to fill the `target.object` with the declaring class,
// so we can use `target.object` as temporary for the `ArtMethod*`. For instance fields,
// we do not need the declaring class, so we can forget the `ArtMethod*` when
// we load the `target.offset`, so use the `target.offset` to hold the `ArtMethod*`.
Register method = (expected_coordinates_count == 0) ? target.object : target.offset;
const MemberOffset art_field_offset = mirror::FieldVarHandle::ArtFieldOffset();
const MemberOffset offset_offset = ArtField::OffsetOffset();
// Load the ArtField, the offset and, if needed, declaring class.
__ Ldr(method.X(), HeapOperand(varhandle, art_field_offset.Int32Value()));
__ Ldr(target.offset, MemOperand(method.X(), offset_offset.Int32Value()));
if (expected_coordinates_count == 0u) {
codegen->GenerateGcRootFieldLoad(invoke,
LocationFrom(target.object),
method.X(),
ArtField::DeclaringClassOffset().Int32Value(),
/*fixup_label=*/ nullptr,
kCompilerReadBarrierOption);
}
} else {
DCHECK_EQ(expected_coordinates_count, 2u);
DataType::Type value_type =
GetVarHandleExpectedValueType(invoke, /*expected_coordinates_count=*/ 2u);
size_t size_shift = DataType::SizeShift(value_type);
MemberOffset data_offset = mirror::Array::DataOffset(DataType::Size(value_type));
Register index = InputRegisterAt(invoke, 2);
Register shifted_index = index;
if (size_shift != 0u) {
shifted_index = target.offset;
__ Lsl(shifted_index, index, size_shift);
}
__ Add(target.offset, shifted_index, data_offset.Int32Value());
}
}
static bool HasVarHandleIntrinsicImplementation(HInvoke* invoke) {
size_t expected_coordinates_count = GetExpectedVarHandleCoordinatesCount(invoke);
if (expected_coordinates_count > 2u) {
// Invalid coordinate count. This invoke shall throw at runtime.
return false;
}
if (expected_coordinates_count != 0u &&
invoke->InputAt(1)->GetType() != DataType::Type::kReference) {
// Except for static fields (no coordinates), the first coordinate must be a reference.
return false;
}
if (expected_coordinates_count == 2u) {
// For arrays and views, the second coordinate must be convertible to `int`.
// In this context, `boolean` is not convertible but we have to look at the shorty
// as compiler transformations can give the invoke a valid boolean input.
DataType::Type index_type = GetDataTypeFromShorty(invoke, 2);
if (index_type == DataType::Type::kBool ||
DataType::Kind(index_type) != DataType::Type::kInt32) {
return false;
}
}
uint32_t number_of_arguments = invoke->GetNumberOfArguments();
DataType::Type return_type = invoke->GetType();
mirror::VarHandle::AccessModeTemplate access_mode_template =
mirror::VarHandle::GetAccessModeTemplateByIntrinsic(invoke->GetIntrinsic());
switch (access_mode_template) {
case mirror::VarHandle::AccessModeTemplate::kGet:
// The return type should be the same as varType, so it shouldn't be void.
if (return_type == DataType::Type::kVoid) {
return false;
}
break;
case mirror::VarHandle::AccessModeTemplate::kSet:
if (return_type != DataType::Type::kVoid) {
return false;
}
break;
case mirror::VarHandle::AccessModeTemplate::kCompareAndSet: {
if (return_type != DataType::Type::kBool) {
return false;
}
uint32_t expected_value_index = number_of_arguments - 2;
uint32_t new_value_index = number_of_arguments - 1;
DataType::Type expected_value_type = GetDataTypeFromShorty(invoke, expected_value_index);
DataType::Type new_value_type = GetDataTypeFromShorty(invoke, new_value_index);
if (expected_value_type != new_value_type) {
return false;
}
break;
}
case mirror::VarHandle::AccessModeTemplate::kCompareAndExchange: {
uint32_t expected_value_index = number_of_arguments - 2;
uint32_t new_value_index = number_of_arguments - 1;
DataType::Type expected_value_type = GetDataTypeFromShorty(invoke, expected_value_index);
DataType::Type new_value_type = GetDataTypeFromShorty(invoke, new_value_index);
if (expected_value_type != new_value_type || return_type != expected_value_type) {
return false;
}
break;
}
case mirror::VarHandle::AccessModeTemplate::kGetAndUpdate: {
DataType::Type value_type = GetDataTypeFromShorty(invoke, number_of_arguments - 1);
if (IsVarHandleGetAndAdd(invoke) &&
(value_type == DataType::Type::kReference || value_type == DataType::Type::kBool)) {
// We should only add numerical types.
return false;
} else if (IsVarHandleGetAndBitwiseOp(invoke) && !DataType::IsIntegralType(value_type)) {
// We can only apply operators to bitwise integral types.
// Note that bitwise VarHandle operations accept a non-integral boolean type and
// perform the appropriate logical operation. However, the result is the same as
// using the bitwise operation on our boolean representation and this fits well
// with DataType::IsIntegralType() treating the compiler type kBool as integral.
return false;
}
if (value_type != return_type) {
return false;
}
break;
}
}
return true;
}
static LocationSummary* CreateVarHandleCommonLocations(HInvoke* invoke) {
size_t expected_coordinates_count = GetExpectedVarHandleCoordinatesCount(invoke);
DataType::Type return_type = invoke->GetType();
ArenaAllocator* allocator = invoke->GetBlock()->GetGraph()->GetAllocator();
LocationSummary* locations =
new (allocator) LocationSummary(invoke, LocationSummary::kCallOnSlowPath, kIntrinsified);
locations->SetInAt(0, Location::RequiresRegister());
// Require coordinates in registers. These are the object holding the value
// to operate on (except for static fields) and index (for arrays and views).
for (size_t i = 0; i != expected_coordinates_count; ++i) {
locations->SetInAt(/* VarHandle object */ 1u + i, Location::RequiresRegister());
}
if (return_type != DataType::Type::kVoid) {
if (DataType::IsFloatingPointType(return_type)) {
locations->SetOut(Location::RequiresFpuRegister());
} else {
locations->SetOut(Location::RequiresRegister());
}
}
uint32_t arguments_start = /* VarHandle object */ 1u + expected_coordinates_count;
uint32_t number_of_arguments = invoke->GetNumberOfArguments();
for (size_t arg_index = arguments_start; arg_index != number_of_arguments; ++arg_index) {
HInstruction* arg = invoke->InputAt(arg_index);
if (IsConstantZeroBitPattern(arg)) {
locations->SetInAt(arg_index, Location::ConstantLocation(arg->AsConstant()));
} else if (DataType::IsFloatingPointType(arg->GetType())) {
locations->SetInAt(arg_index, Location::RequiresFpuRegister());
} else {
locations->SetInAt(arg_index, Location::RequiresRegister());
}
}
// Add a temporary for offset.
if ((kEmitCompilerReadBarrier && !kUseBakerReadBarrier) &&
GetExpectedVarHandleCoordinatesCount(invoke) == 0u) { // For static fields.
// To preserve the offset value across the non-Baker read barrier slow path
// for loading the declaring class, use a fixed callee-save register.
constexpr int first_callee_save = CTZ(kArm64CalleeSaveRefSpills);
locations->AddTemp(Location::RegisterLocation(first_callee_save));
} else {
locations->AddTemp(Location::RequiresRegister());
}
if (expected_coordinates_count == 0u) {
// Add a temporary to hold the declaring class.
locations->AddTemp(Location::RequiresRegister());
}
return locations;
}
static void CreateVarHandleGetLocations(HInvoke* invoke) {
if (!HasVarHandleIntrinsicImplementation(invoke)) {
return;
}
if ((kEmitCompilerReadBarrier && !kUseBakerReadBarrier) &&
invoke->GetType() == DataType::Type::kReference &&
invoke->GetIntrinsic() != Intrinsics::kVarHandleGet &&
invoke->GetIntrinsic() != Intrinsics::kVarHandleGetOpaque) {
// Unsupported for non-Baker read barrier because the artReadBarrierSlow() ignores
// the passed reference and reloads it from the field. This gets the memory visibility
// wrong for Acquire/Volatile operations. b/173104084
return;
}
CreateVarHandleCommonLocations(invoke);
}
static void GenerateVarHandleGet(HInvoke* invoke,
CodeGeneratorARM64* codegen,
std::memory_order order,
bool byte_swap = false) {
DataType::Type type = invoke->GetType();
DCHECK_NE(type, DataType::Type::kVoid);
LocationSummary* locations = invoke->GetLocations();
MacroAssembler* masm = codegen->GetVIXLAssembler();
CPURegister out = helpers::OutputCPURegister(invoke);
VarHandleTarget target = GetVarHandleTarget(invoke);
VarHandleSlowPathARM64* slow_path = nullptr;
if (!byte_swap) {
slow_path = GenerateVarHandleChecks(invoke, codegen, order, type);
GenerateVarHandleTarget(invoke, target, codegen);
__ Bind(slow_path->GetNativeByteOrderLabel());
}
// ARM64 load-acquire instructions are implicitly sequentially consistent.
bool use_load_acquire =
(order == std::memory_order_acquire) || (order == std::memory_order_seq_cst);
DCHECK(use_load_acquire || order == std::memory_order_relaxed);
// Load the value from the target location.
if (type == DataType::Type::kReference && kEmitCompilerReadBarrier && kUseBakerReadBarrier) {
// Piggy-back on the field load path using introspection for the Baker read barrier.
// The `target.offset` is a temporary, use it for field address.
Register tmp_ptr = target.offset.X();
__ Add(tmp_ptr, target.object.X(), target.offset.X());
codegen->GenerateFieldLoadWithBakerReadBarrier(invoke,
locations->Out(),
target.object,
MemOperand(tmp_ptr),
/*needs_null_check=*/ false,
use_load_acquire);
DCHECK(!byte_swap);
} else {
MemOperand address(target.object.X(), target.offset.X());
CPURegister load_reg = out;
DataType::Type load_type = type;
UseScratchRegisterScope temps(masm);
if (byte_swap) {
if (type == DataType::Type::kInt16) {
// Avoid unnecessary sign extension before REV16.
load_type = DataType::Type::kUint16;
} else if (type == DataType::Type::kFloat32) {
load_type = DataType::Type::kInt32;
load_reg = target.offset.W();
} else if (type == DataType::Type::kFloat64) {
load_type = DataType::Type::kInt64;
load_reg = target.offset.X();
}
}
if (use_load_acquire) {
codegen->LoadAcquire(invoke, load_type, load_reg, address, /*needs_null_check=*/ false);
} else {
codegen->Load(load_type, load_reg, address);
}
if (type == DataType::Type::kReference) {
DCHECK(!byte_swap);
DCHECK(out.IsW());
Location out_loc = locations->Out();
Location object_loc = LocationFrom(target.object);
Location offset_loc = LocationFrom(target.offset);
codegen->MaybeGenerateReadBarrierSlow(invoke, out_loc, out_loc, object_loc, 0u, offset_loc);
} else if (byte_swap) {
GenerateReverseBytes(masm, type, load_reg, out);
}
}
if (!byte_swap) {
__ Bind(slow_path->GetExitLabel());
}
}
void IntrinsicLocationsBuilderARM64::VisitVarHandleGet(HInvoke* invoke) {
CreateVarHandleGetLocations(invoke);
}
void IntrinsicCodeGeneratorARM64::VisitVarHandleGet(HInvoke* invoke) {
GenerateVarHandleGet(invoke, codegen_, std::memory_order_relaxed);
}
void IntrinsicLocationsBuilderARM64::VisitVarHandleGetOpaque(HInvoke* invoke) {
CreateVarHandleGetLocations(invoke);
}
void IntrinsicCodeGeneratorARM64::VisitVarHandleGetOpaque(HInvoke* invoke) {
GenerateVarHandleGet(invoke, codegen_, std::memory_order_relaxed);
}
void IntrinsicLocationsBuilderARM64::VisitVarHandleGetAcquire(HInvoke* invoke) {
CreateVarHandleGetLocations(invoke);
}
void IntrinsicCodeGeneratorARM64::VisitVarHandleGetAcquire(HInvoke* invoke) {
GenerateVarHandleGet(invoke, codegen_, std::memory_order_acquire);
}
void IntrinsicLocationsBuilderARM64::VisitVarHandleGetVolatile(HInvoke* invoke) {
CreateVarHandleGetLocations(invoke);
}
void IntrinsicCodeGeneratorARM64::VisitVarHandleGetVolatile(HInvoke* invoke) {
GenerateVarHandleGet(invoke, codegen_, std::memory_order_seq_cst);
}
static void CreateVarHandleSetLocations(HInvoke* invoke) {
if (!HasVarHandleIntrinsicImplementation(invoke)) {
return;
}
CreateVarHandleCommonLocations(invoke);
}
static void GenerateVarHandleSet(HInvoke* invoke,
CodeGeneratorARM64* codegen,
std::memory_order order,
bool byte_swap = false) {
uint32_t value_index = invoke->GetNumberOfArguments() - 1;
DataType::Type value_type = GetDataTypeFromShorty(invoke, value_index);
MacroAssembler* masm = codegen->GetVIXLAssembler();
CPURegister value = InputCPURegisterOrZeroRegAt(invoke, value_index);
VarHandleTarget target = GetVarHandleTarget(invoke);
VarHandleSlowPathARM64* slow_path = nullptr;
if (!byte_swap) {
slow_path = GenerateVarHandleChecks(invoke, codegen, order, value_type);
GenerateVarHandleTarget(invoke, target, codegen);
__ Bind(slow_path->GetNativeByteOrderLabel());
}
// ARM64 store-release instructions are implicitly sequentially consistent.
bool use_store_release =
(order == std::memory_order_release) || (order == std::memory_order_seq_cst);
DCHECK(use_store_release || order == std::memory_order_relaxed);
// Store the value to the target location.
{
CPURegister source = value;
UseScratchRegisterScope temps(masm);
if (kPoisonHeapReferences && value_type == DataType::Type::kReference) {
DCHECK(value.IsW());
Register temp = temps.AcquireW();
__ Mov(temp, value.W());
codegen->GetAssembler()->PoisonHeapReference(temp);
source = temp;
}
if (byte_swap) {
DCHECK(!source.IsZero()); // We use the main path for zero as it does not need a byte swap.
Register temp = source.Is64Bits() ? temps.AcquireX() : temps.AcquireW();
if (value_type == DataType::Type::kInt16) {
// Avoid unnecessary sign extension before storing.
value_type = DataType::Type::kUint16;
} else if (DataType::IsFloatingPointType(value_type)) {
__ Fmov(temp, source.Is64Bits() ? source.D() : source.S());
value_type = source.Is64Bits() ? DataType::Type::kInt64 : DataType::Type::kInt32;
source = temp; // Source for the `GenerateReverseBytes()` below.
}
GenerateReverseBytes(masm, value_type, source, temp);
source = temp;
}
MemOperand address(target.object.X(), target.offset.X());
if (use_store_release) {
codegen->StoreRelease(invoke, value_type, source, address, /*needs_null_check=*/ false);
} else {
codegen->Store(value_type, source, address);
}
}
if (CodeGenerator::StoreNeedsWriteBarrier(value_type, invoke->InputAt(value_index))) {
codegen->MarkGCCard(target.object, Register(value), /*value_can_be_null=*/ true);
}
if (!byte_swap) {
__ Bind(slow_path->GetExitLabel());
}
}
void IntrinsicLocationsBuilderARM64::VisitVarHandleSet(HInvoke* invoke) {
CreateVarHandleSetLocations(invoke);
}
void IntrinsicCodeGeneratorARM64::VisitVarHandleSet(HInvoke* invoke) {
GenerateVarHandleSet(invoke, codegen_, std::memory_order_relaxed);
}
void IntrinsicLocationsBuilderARM64::VisitVarHandleSetOpaque(HInvoke* invoke) {
CreateVarHandleSetLocations(invoke);
}
void IntrinsicCodeGeneratorARM64::VisitVarHandleSetOpaque(HInvoke* invoke) {
GenerateVarHandleSet(invoke, codegen_, std::memory_order_relaxed);
}
void IntrinsicLocationsBuilderARM64::VisitVarHandleSetRelease(HInvoke* invoke) {
CreateVarHandleSetLocations(invoke);
}
void IntrinsicCodeGeneratorARM64::VisitVarHandleSetRelease(HInvoke* invoke) {
GenerateVarHandleSet(invoke, codegen_, std::memory_order_release);
}
void IntrinsicLocationsBuilderARM64::VisitVarHandleSetVolatile(HInvoke* invoke) {
CreateVarHandleSetLocations(invoke);
}
void IntrinsicCodeGeneratorARM64::VisitVarHandleSetVolatile(HInvoke* invoke) {
GenerateVarHandleSet(invoke, codegen_, std::memory_order_seq_cst);
}
static void CreateVarHandleCompareAndSetOrExchangeLocations(HInvoke* invoke, bool return_success) {
if (!HasVarHandleIntrinsicImplementation(invoke)) {
return;
}
uint32_t number_of_arguments = invoke->GetNumberOfArguments();
DataType::Type value_type = GetDataTypeFromShorty(invoke, number_of_arguments - 1u);
if ((kEmitCompilerReadBarrier && !kUseBakerReadBarrier) &&
value_type == DataType::Type::kReference) {
// Unsupported for non-Baker read barrier because the artReadBarrierSlow() ignores
// the passed reference and reloads it from the field. This breaks the read barriers
// in slow path in different ways. The marked old value may not actually be a to-space
// reference to the same object as `old_value`, breaking slow path assumptions. And
// for CompareAndExchange, marking the old value after comparison failure may actually
// return the reference to `expected`, erroneously indicating success even though we
// did not set the new value. (And it also gets the memory visibility wrong.) b/173104084
return;
}
LocationSummary* locations = CreateVarHandleCommonLocations(invoke);
if (kEmitCompilerReadBarrier && !kUseBakerReadBarrier) {
// We need callee-save registers for both the class object and offset instead of
// the temporaries reserved in CreateVarHandleCommonLocations().
static_assert(POPCOUNT(kArm64CalleeSaveRefSpills) >= 2u);
uint32_t first_callee_save = CTZ(kArm64CalleeSaveRefSpills);
uint32_t second_callee_save = CTZ(kArm64CalleeSaveRefSpills ^ (1u << first_callee_save));
if (GetExpectedVarHandleCoordinatesCount(invoke) == 0u) { // For static fields.
DCHECK_EQ(locations->GetTempCount(), 2u);
DCHECK(locations->GetTemp(0u).Equals(Location::RequiresRegister()));
DCHECK(locations->GetTemp(1u).Equals(Location::RegisterLocation(first_callee_save)));
locations->SetTempAt(0u, Location::RegisterLocation(second_callee_save));
} else {
DCHECK_EQ(locations->GetTempCount(), 1u);
DCHECK(locations->GetTemp(0u).Equals(Location::RequiresRegister()));
locations->SetTempAt(0u, Location::RegisterLocation(first_callee_save));
}
}
size_t old_temp_count = locations->GetTempCount();
DCHECK_EQ(old_temp_count, (GetExpectedVarHandleCoordinatesCount(invoke) == 0) ? 2u : 1u);
if (!return_success) {
if (DataType::IsFloatingPointType(value_type)) {
// Add a temporary for old value and exclusive store result if floating point
// `expected` and/or `new_value` take scratch registers.
size_t available_scratch_registers =
(IsConstantZeroBitPattern(invoke->InputAt(number_of_arguments - 1u)) ? 1u : 0u) +
(IsConstantZeroBitPattern(invoke->InputAt(number_of_arguments - 2u)) ? 1u : 0u);
size_t temps_needed = /* pointer, old value, store result */ 3u - available_scratch_registers;
// We can reuse the declaring class (if present) and offset temporary.
if (temps_needed > old_temp_count) {
locations->AddRegisterTemps(temps_needed - old_temp_count);
}
} else if ((value_type != DataType::Type::kReference && DataType::Size(value_type) != 1u) &&
!IsConstantZeroBitPattern(invoke->InputAt(number_of_arguments - 2u)) &&
!IsConstantZeroBitPattern(invoke->InputAt(number_of_arguments - 1u)) &&
GetExpectedVarHandleCoordinatesCount(invoke) == 2u) {
// Allocate a normal temporary for store result in the non-native byte order path
// because scratch registers are used by the byte-swapped `expected` and `new_value`.
DCHECK_EQ(old_temp_count, 1u);
locations->AddTemp(Location::RequiresRegister());
}
}
if (kEmitCompilerReadBarrier && value_type == DataType::Type::kReference) {
// Add a temporary for the `old_value_temp` in slow path.
locations->AddTemp(Location::RequiresRegister());
}
}
static Register MoveToTempIfFpRegister(const CPURegister& cpu_reg,
DataType::Type type,
MacroAssembler* masm,
UseScratchRegisterScope* temps) {
if (cpu_reg.IsS()) {
DCHECK_EQ(type, DataType::Type::kFloat32);
Register reg = temps->AcquireW();
__ Fmov(reg, cpu_reg.S());
return reg;
} else if (cpu_reg.IsD()) {
DCHECK_EQ(type, DataType::Type::kFloat64);
Register reg = temps->AcquireX();
__ Fmov(reg, cpu_reg.D());
return reg;
} else {
return DataType::Is64BitType(type) ? cpu_reg.X() : cpu_reg.W();
}
}
static void GenerateVarHandleCompareAndSetOrExchange(HInvoke* invoke,
CodeGeneratorARM64* codegen,
std::memory_order order,
bool return_success,
bool strong,
bool byte_swap = false) {
DCHECK(return_success || strong);
uint32_t expected_index = invoke->GetNumberOfArguments() - 2;
uint32_t new_value_index = invoke->GetNumberOfArguments() - 1;
DataType::Type value_type = GetDataTypeFromShorty(invoke, new_value_index);
DCHECK_EQ(value_type, GetDataTypeFromShorty(invoke, expected_index));
MacroAssembler* masm = codegen->GetVIXLAssembler();
LocationSummary* locations = invoke->GetLocations();
CPURegister expected = InputCPURegisterOrZeroRegAt(invoke, expected_index);
CPURegister new_value = InputCPURegisterOrZeroRegAt(invoke, new_value_index);
CPURegister out = helpers::OutputCPURegister(invoke);
VarHandleTarget target = GetVarHandleTarget(invoke);
VarHandleSlowPathARM64* slow_path = nullptr;
if (!byte_swap) {
slow_path = GenerateVarHandleChecks(invoke, codegen, order, value_type);
slow_path->SetCompareAndSetOrExchangeArgs(return_success, strong);
GenerateVarHandleTarget(invoke, target, codegen);
__ Bind(slow_path->GetNativeByteOrderLabel());
}
// This needs to be before the temp registers, as MarkGCCard also uses VIXL temps.
if (CodeGenerator::StoreNeedsWriteBarrier(value_type, invoke->InputAt(new_value_index))) {
// Mark card for object assuming new value is stored.
bool new_value_can_be_null = true; // TODO: Worth finding out this information?
codegen->MarkGCCard(target.object, new_value.W(), new_value_can_be_null);
}
// Reuse the `offset` temporary for the pointer to the target location,
// except for references that need the offset for the read barrier.
UseScratchRegisterScope temps(masm);
Register tmp_ptr = target.offset.X();
if (kEmitCompilerReadBarrier && value_type == DataType::Type::kReference) {
tmp_ptr = temps.AcquireX();
}
__ Add(tmp_ptr, target.object.X(), target.offset.X());
// Move floating point values to scratch registers.
// Note that float/double CAS uses bitwise comparison, rather than the operator==.
Register expected_reg = MoveToTempIfFpRegister(expected, value_type, masm, &temps);
Register new_value_reg = MoveToTempIfFpRegister(new_value, value_type, masm, &temps);
bool is_fp = DataType::IsFloatingPointType(value_type);
DataType::Type cas_type = is_fp
? ((value_type == DataType::Type::kFloat64) ? DataType::Type::kInt64 : DataType::Type::kInt32)
: value_type;
// Avoid sign extension in the CAS loop by zero-extending `expected` before the loop. This adds
// one instruction for CompareAndExchange as we shall need to sign-extend the returned value.
if (value_type == DataType::Type::kInt16 && !expected.IsZero()) {
Register temp = temps.AcquireW();
__ Uxth(temp, expected_reg);
expected_reg = temp;
cas_type = DataType::Type::kUint16;
} else if (value_type == DataType::Type::kInt8 && !expected.IsZero()) {
Register temp = temps.AcquireW();
__ Uxtb(temp, expected_reg);
expected_reg = temp;
cas_type = DataType::Type::kUint8;
}
if (byte_swap) {
// Do the byte swap and move values to scratch registers if needed.
// Non-zero FP values and non-zero `expected` for `kInt16` are already in scratch registers.
DCHECK_NE(value_type, DataType::Type::kInt8);
if (!expected.IsZero()) {
bool is_scratch = is_fp || (value_type == DataType::Type::kInt16);
Register temp = is_scratch ? expected_reg : temps.AcquireSameSizeAs(expected_reg);
GenerateReverseBytes(masm, cas_type, expected_reg, temp);
expected_reg = temp;
}
if (!new_value.IsZero()) {
Register temp = is_fp ? new_value_reg : temps.AcquireSameSizeAs(new_value_reg);
GenerateReverseBytes(masm, cas_type, new_value_reg, temp);
new_value_reg = temp;
}
}
// Prepare registers for old value and the result of the exclusive store.
Register old_value;
Register store_result;
if (return_success) {
// Use the output register for both old value and exclusive store result.
old_value = (cas_type == DataType::Type::kInt64) ? out.X() : out.W();
store_result = out.W();
} else if (DataType::IsFloatingPointType(value_type)) {
// We need two temporary registers but we have already used scratch registers for
// holding the expected and new value unless they are zero bit pattern (+0.0f or
// +0.0). We have allocated sufficient normal temporaries to handle that.
size_t next_temp = 1u;
if (expected.IsZero()) {
old_value = (cas_type == DataType::Type::kInt64) ? temps.AcquireX() : temps.AcquireW();
} else {
Location temp = locations->GetTemp(next_temp);
++next_temp;
old_value = (cas_type == DataType::Type::kInt64) ? XRegisterFrom(temp) : WRegisterFrom(temp);
}
store_result =
new_value.IsZero() ? temps.AcquireW() : WRegisterFrom(locations->GetTemp(next_temp));
DCHECK(!old_value.Is(tmp_ptr));
DCHECK(!store_result.Is(tmp_ptr));
} else {
// Use the output register for the old value.
old_value = (cas_type == DataType::Type::kInt64) ? out.X() : out.W();
// Use scratch register for the store result, except when we have used up
// scratch registers for byte-swapped `expected` and `new_value`.
// In that case, we have allocated a normal temporary.
store_result = (byte_swap && !expected.IsZero() && !new_value.IsZero())
? WRegisterFrom(locations->GetTemp(1))
: temps.AcquireW();
DCHECK(!store_result.Is(tmp_ptr));
}
vixl::aarch64::Label exit_loop_label;
vixl::aarch64::Label* exit_loop = &exit_loop_label;
vixl::aarch64::Label* cmp_failure = &exit_loop_label;
if (kEmitCompilerReadBarrier && value_type == DataType::Type::kReference) {
// The `old_value_temp` is used first for the marked `old_value` and then for the unmarked
// reloaded old value for subsequent CAS in the slow path. It cannot be a scratch register.
size_t expected_coordinates_count = GetExpectedVarHandleCoordinatesCount(invoke);
Register old_value_temp =
WRegisterFrom(locations->GetTemp((expected_coordinates_count == 0u) ? 2u : 1u));
// For strong CAS, use a scratch register for the store result in slow path.
// For weak CAS, we need to check the store result, so store it in `store_result`.
Register slow_path_store_result = strong ? Register() : store_result;
ReadBarrierCasSlowPathARM64* rb_slow_path =
new (codegen->GetScopedAllocator()) ReadBarrierCasSlowPathARM64(
invoke,
order,
strong,
target.object,
target.offset.X(),
expected_reg,
new_value_reg,
old_value,
old_value_temp,
slow_path_store_result,
/*update_old_value=*/ !return_success,
codegen);
codegen->AddSlowPath(rb_slow_path);
exit_loop = rb_slow_path->GetExitLabel();
cmp_failure = rb_slow_path->GetEntryLabel();
}
GenerateCompareAndSet(codegen,
cas_type,
order,
strong,
cmp_failure,
tmp_ptr,
new_value_reg,
old_value,
store_result,
expected_reg);
__ Bind(exit_loop);
if (return_success) {
if (strong) {
__ Cset(out.W(), eq);
} else {
// On success, the Z flag is set and the store result is 1, see GenerateCompareAndSet().
// On failure, either the Z flag is clear or the store result is 0.
// Determine the final success value with a CSEL.
__ Csel(out.W(), store_result, wzr, eq);
}
} else if (byte_swap) {
// Also handles moving to FP registers.
GenerateReverseBytes(masm, value_type, old_value, out);
} else if (DataType::IsFloatingPointType(value_type)) {
__ Fmov((value_type == DataType::Type::kFloat64) ? out.D() : out.S(), old_value);
} else if (value_type == DataType::Type::kInt8) {
__ Sxtb(out.W(), old_value);
} else if (value_type == DataType::Type::kInt16) {
__ Sxth(out.W(), old_value);
}
if (!byte_swap) {
__ Bind(slow_path->GetExitLabel());
}
}
void IntrinsicLocationsBuilderARM64::VisitVarHandleCompareAndExchange(HInvoke* invoke) {
CreateVarHandleCompareAndSetOrExchangeLocations(invoke, /*return_success=*/ false);
}
void IntrinsicCodeGeneratorARM64::VisitVarHandleCompareAndExchange(HInvoke* invoke) {
GenerateVarHandleCompareAndSetOrExchange(
invoke, codegen_, std::memory_order_seq_cst, /*return_success=*/ false, /*strong=*/ true);
}
void IntrinsicLocationsBuilderARM64::VisitVarHandleCompareAndExchangeAcquire(HInvoke* invoke) {
CreateVarHandleCompareAndSetOrExchangeLocations(invoke, /*return_success=*/ false);
}
void IntrinsicCodeGeneratorARM64::VisitVarHandleCompareAndExchangeAcquire(HInvoke* invoke) {
GenerateVarHandleCompareAndSetOrExchange(
invoke, codegen_, std::memory_order_acquire, /*return_success=*/ false, /*strong=*/ true);
}
void IntrinsicLocationsBuilderARM64::VisitVarHandleCompareAndExchangeRelease(HInvoke* invoke) {
CreateVarHandleCompareAndSetOrExchangeLocations(invoke, /*return_success=*/ false);
}
void IntrinsicCodeGeneratorARM64::VisitVarHandleCompareAndExchangeRelease(HInvoke* invoke) {
GenerateVarHandleCompareAndSetOrExchange(
invoke, codegen_, std::memory_order_release, /*return_success=*/ false, /*strong=*/ true);
}
void IntrinsicLocationsBuilderARM64::VisitVarHandleCompareAndSet(HInvoke* invoke) {
CreateVarHandleCompareAndSetOrExchangeLocations(invoke, /*return_success=*/ true);
}
void IntrinsicCodeGeneratorARM64::VisitVarHandleCompareAndSet(HInvoke* invoke) {
GenerateVarHandleCompareAndSetOrExchange(
invoke, codegen_, std::memory_order_seq_cst, /*return_success=*/ true, /*strong=*/ true);
}
void IntrinsicLocationsBuilderARM64::VisitVarHandleWeakCompareAndSet(HInvoke* invoke) {
CreateVarHandleCompareAndSetOrExchangeLocations(invoke, /*return_success=*/ true);
}
void IntrinsicCodeGeneratorARM64::VisitVarHandleWeakCompareAndSet(HInvoke* invoke) {
GenerateVarHandleCompareAndSetOrExchange(
invoke, codegen_, std::memory_order_seq_cst, /*return_success=*/ true, /*strong=*/ false);
}
void IntrinsicLocationsBuilderARM64::VisitVarHandleWeakCompareAndSetAcquire(HInvoke* invoke) {
CreateVarHandleCompareAndSetOrExchangeLocations(invoke, /*return_success=*/ true);
}
void IntrinsicCodeGeneratorARM64::VisitVarHandleWeakCompareAndSetAcquire(HInvoke* invoke) {
GenerateVarHandleCompareAndSetOrExchange(
invoke, codegen_, std::memory_order_acquire, /*return_success=*/ true, /*strong=*/ false);
}
void IntrinsicLocationsBuilderARM64::VisitVarHandleWeakCompareAndSetPlain(HInvoke* invoke) {
CreateVarHandleCompareAndSetOrExchangeLocations(invoke, /*return_success=*/ true);
}
void IntrinsicCodeGeneratorARM64::VisitVarHandleWeakCompareAndSetPlain(HInvoke* invoke) {
GenerateVarHandleCompareAndSetOrExchange(
invoke, codegen_, std::memory_order_relaxed, /*return_success=*/ true, /*strong=*/ false);
}
void IntrinsicLocationsBuilderARM64::VisitVarHandleWeakCompareAndSetRelease(HInvoke* invoke) {
CreateVarHandleCompareAndSetOrExchangeLocations(invoke, /*return_success=*/ true);
}
void IntrinsicCodeGeneratorARM64::VisitVarHandleWeakCompareAndSetRelease(HInvoke* invoke) {
GenerateVarHandleCompareAndSetOrExchange(
invoke, codegen_, std::memory_order_release, /*return_success=*/ true, /*strong=*/ false);
}
static void CreateVarHandleGetAndUpdateLocations(HInvoke* invoke,
GetAndUpdateOp get_and_update_op) {
if (!HasVarHandleIntrinsicImplementation(invoke)) {
return;
}
if ((kEmitCompilerReadBarrier && !kUseBakerReadBarrier) &&
invoke->GetType() == DataType::Type::kReference) {
// Unsupported for non-Baker read barrier because the artReadBarrierSlow() ignores
// the passed reference and reloads it from the field, thus seeing the new value
// that we have just stored. (And it also gets the memory visibility wrong.) b/173104084
return;
}
LocationSummary* locations = CreateVarHandleCommonLocations(invoke);
size_t old_temp_count = locations->GetTempCount();
DCHECK_EQ(old_temp_count, (GetExpectedVarHandleCoordinatesCount(invoke) == 0) ? 2u : 1u);
if (DataType::IsFloatingPointType(invoke->GetType())) {
if (get_and_update_op == GetAndUpdateOp::kAdd) {
// For ADD, do not use ZR for zero bit pattern (+0.0f or +0.0).
locations->SetInAt(invoke->GetNumberOfArguments() - 1u, Location::RequiresFpuRegister());
} else {
DCHECK(get_and_update_op == GetAndUpdateOp::kSet);
// We can reuse the declaring class temporary if present.
if (old_temp_count == 1u &&
!IsConstantZeroBitPattern(invoke->InputAt(invoke->GetNumberOfArguments() - 1u))) {
// Add a temporary for `old_value` if floating point `new_value` takes a scratch register.
locations->AddTemp(Location::RequiresRegister());
}
}
}
// We need a temporary for the byte-swap path for bitwise operations unless the argument is a
// zero which does not need a byte-swap. We can reuse the declaring class temporary if present.
if (old_temp_count == 1u &&
(get_and_update_op != GetAndUpdateOp::kSet && get_and_update_op != GetAndUpdateOp::kAdd) &&
GetExpectedVarHandleCoordinatesCount(invoke) == 2u &&
!IsConstantZeroBitPattern(invoke->InputAt(invoke->GetNumberOfArguments() - 1u))) {
DataType::Type value_type =
GetVarHandleExpectedValueType(invoke, /*expected_coordinates_count=*/ 2u);
if (value_type != DataType::Type::kReference && DataType::Size(value_type) != 1u) {
locations->AddTemp(Location::RequiresRegister());
}
}
}
static void GenerateVarHandleGetAndUpdate(HInvoke* invoke,
CodeGeneratorARM64* codegen,
GetAndUpdateOp get_and_update_op,
std::memory_order order,
bool byte_swap = false) {
uint32_t arg_index = invoke->GetNumberOfArguments() - 1;
DataType::Type value_type = GetDataTypeFromShorty(invoke, arg_index);
MacroAssembler* masm = codegen->GetVIXLAssembler();
LocationSummary* locations = invoke->GetLocations();
CPURegister arg = InputCPURegisterOrZeroRegAt(invoke, arg_index);
CPURegister out = helpers::OutputCPURegister(invoke);
VarHandleTarget target = GetVarHandleTarget(invoke);
VarHandleSlowPathARM64* slow_path = nullptr;
if (!byte_swap) {
slow_path = GenerateVarHandleChecks(invoke, codegen, order, value_type);
slow_path->SetGetAndUpdateOp(get_and_update_op);
GenerateVarHandleTarget(invoke, target, codegen);
__ Bind(slow_path->GetNativeByteOrderLabel());
}
// This needs to be before the temp registers, as MarkGCCard also uses VIXL temps.
if (CodeGenerator::StoreNeedsWriteBarrier(value_type, invoke->InputAt(arg_index))) {
DCHECK(get_and_update_op == GetAndUpdateOp::kSet);
// Mark card for object, the new value shall be stored.
bool new_value_can_be_null = true; // TODO: Worth finding out this information?
codegen->MarkGCCard(target.object, arg.W(), new_value_can_be_null);
}
// Reuse the `target.offset` temporary for the pointer to the target location,
// except for references that need the offset for the non-Baker read barrier.
UseScratchRegisterScope temps(masm);
Register tmp_ptr = target.offset.X();
if ((kEmitCompilerReadBarrier && !kUseBakerReadBarrier) &&
value_type == DataType::Type::kReference) {
tmp_ptr = temps.AcquireX();
}
__ Add(tmp_ptr, target.object.X(), target.offset.X());
// The load/store type is never floating point.
bool is_fp = DataType::IsFloatingPointType(value_type);
DataType::Type load_store_type = is_fp
? ((value_type == DataType::Type::kFloat32) ? DataType::Type::kInt32 : DataType::Type::kInt64)
: value_type;
// Avoid sign extension in the CAS loop. Sign-extend after the loop.
// Note: Using unsigned values yields the same value to store (we do not store higher bits).
if (value_type == DataType::Type::kInt8) {
load_store_type = DataType::Type::kUint8;
} else if (value_type == DataType::Type::kInt16) {
load_store_type = DataType::Type::kUint16;
}
// Prepare register for old value.
CPURegister old_value = out;
if (get_and_update_op == GetAndUpdateOp::kSet) {
// For floating point GetAndSet, do the GenerateGetAndUpdate() with core registers,
// rather than moving between core and FP registers in the loop.
arg = MoveToTempIfFpRegister(arg, value_type, masm, &temps);
if (DataType::IsFloatingPointType(value_type) && !arg.IsZero()) {
// We need a temporary register but we have already used a scratch register for
// the new value unless it is zero bit pattern (+0.0f or +0.0) and need another one
// in GenerateGetAndUpdate(). We have allocated a normal temporary to handle that.
old_value = CPURegisterFrom(locations->GetTemp(1u), load_store_type);
} else if ((kEmitCompilerReadBarrier && kUseBakerReadBarrier) &&
value_type == DataType::Type::kReference) {
// Load the old value initially to a scratch register.
// We shall move it to `out` later with a read barrier.
old_value = temps.AcquireW();
}
}
if (byte_swap) {
DCHECK_NE(value_type, DataType::Type::kReference);
DCHECK_NE(DataType::Size(value_type), 1u);
if (get_and_update_op == GetAndUpdateOp::kAdd) {
// We need to do the byte swapping in the CAS loop for GetAndAdd.
get_and_update_op = GetAndUpdateOp::kAddWithByteSwap;
} else if (!arg.IsZero()) {
// For other operations, avoid byte swap inside the CAS loop by providing an adjusted `arg`.
// For GetAndSet use a scratch register; FP argument is already in a scratch register.
// For bitwise operations GenerateGetAndUpdate() needs both scratch registers;
// we have allocated a normal temporary to handle that.
CPURegister temp = (get_and_update_op == GetAndUpdateOp::kSet)
? (is_fp ? arg : (arg.Is64Bits() ? temps.AcquireX() : temps.AcquireW()))
: CPURegisterFrom(locations->GetTemp(1u), load_store_type);
GenerateReverseBytes(masm, load_store_type, arg, temp);
arg = temp;
}
}
GenerateGetAndUpdate(codegen, get_and_update_op, load_store_type, order, tmp_ptr, arg, old_value);
if (get_and_update_op == GetAndUpdateOp::kAddWithByteSwap) {
// The only adjustment needed is sign-extension for `kInt16`.
// Everything else has been done by the `GenerateGetAndUpdate()`.
DCHECK(byte_swap);
if (value_type == DataType::Type::kInt16) {
DCHECK_EQ(load_store_type, DataType::Type::kUint16);
__ Sxth(out.W(), old_value.W());
}
} else if (byte_swap) {
// Also handles moving to FP registers.
GenerateReverseBytes(masm, value_type, old_value, out);
} else if (get_and_update_op == GetAndUpdateOp::kSet && value_type == DataType::Type::kFloat64) {
__ Fmov(out.D(), old_value.X());
} else if (get_and_update_op == GetAndUpdateOp::kSet && value_type == DataType::Type::kFloat32) {
__ Fmov(out.S(), old_value.W());
} else if (value_type == DataType::Type::kInt8) {
__ Sxtb(out.W(), old_value.W());
} else if (value_type == DataType::Type::kInt16) {
__ Sxth(out.W(), old_value.W());
} else if (kEmitCompilerReadBarrier && value_type == DataType::Type::kReference) {
if (kUseBakerReadBarrier) {
codegen->GenerateIntrinsicCasMoveWithBakerReadBarrier(out.W(), old_value.W());
} else {
codegen->GenerateReadBarrierSlow(
invoke,
Location::RegisterLocation(out.GetCode()),
Location::RegisterLocation(old_value.GetCode()),
Location::RegisterLocation(target.object.GetCode()),
/*offset=*/ 0u,
/*index=*/ Location::RegisterLocation(target.offset.GetCode()));
}
}
if (!byte_swap) {
__ Bind(slow_path->GetExitLabel());
}
}
void IntrinsicLocationsBuilderARM64::VisitVarHandleGetAndSet(HInvoke* invoke) {
CreateVarHandleGetAndUpdateLocations(invoke, GetAndUpdateOp::kSet);
}
void IntrinsicCodeGeneratorARM64::VisitVarHandleGetAndSet(HInvoke* invoke) {
GenerateVarHandleGetAndUpdate(invoke, codegen_, GetAndUpdateOp::kSet, std::memory_order_seq_cst);
}
void IntrinsicLocationsBuilderARM64::VisitVarHandleGetAndSetAcquire(HInvoke* invoke) {
CreateVarHandleGetAndUpdateLocations(invoke, GetAndUpdateOp::kSet);
}
void IntrinsicCodeGeneratorARM64::VisitVarHandleGetAndSetAcquire(HInvoke* invoke) {
GenerateVarHandleGetAndUpdate(invoke, codegen_, GetAndUpdateOp::kSet, std::memory_order_acquire);
}
void IntrinsicLocationsBuilderARM64::VisitVarHandleGetAndSetRelease(HInvoke* invoke) {
CreateVarHandleGetAndUpdateLocations(invoke, GetAndUpdateOp::kSet);
}
void IntrinsicCodeGeneratorARM64::VisitVarHandleGetAndSetRelease(HInvoke* invoke) {
GenerateVarHandleGetAndUpdate(invoke, codegen_, GetAndUpdateOp::kSet, std::memory_order_release);
}
void IntrinsicLocationsBuilderARM64::VisitVarHandleGetAndAdd(HInvoke* invoke) {
CreateVarHandleGetAndUpdateLocations(invoke, GetAndUpdateOp::kAdd);
}
void IntrinsicCodeGeneratorARM64::VisitVarHandleGetAndAdd(HInvoke* invoke) {
GenerateVarHandleGetAndUpdate(invoke, codegen_, GetAndUpdateOp::kAdd, std::memory_order_seq_cst);
}
void IntrinsicLocationsBuilderARM64::VisitVarHandleGetAndAddAcquire(HInvoke* invoke) {
CreateVarHandleGetAndUpdateLocations(invoke, GetAndUpdateOp::kAdd);
}
void IntrinsicCodeGeneratorARM64::VisitVarHandleGetAndAddAcquire(HInvoke* invoke) {
GenerateVarHandleGetAndUpdate(invoke, codegen_, GetAndUpdateOp::kAdd, std::memory_order_acquire);
}
void IntrinsicLocationsBuilderARM64::VisitVarHandleGetAndAddRelease(HInvoke* invoke) {
CreateVarHandleGetAndUpdateLocations(invoke, GetAndUpdateOp::kAdd);
}
void IntrinsicCodeGeneratorARM64::VisitVarHandleGetAndAddRelease(HInvoke* invoke) {
GenerateVarHandleGetAndUpdate(invoke, codegen_, GetAndUpdateOp::kAdd, std::memory_order_release);
}
void IntrinsicLocationsBuilderARM64::VisitVarHandleGetAndBitwiseAnd(HInvoke* invoke) {
CreateVarHandleGetAndUpdateLocations(invoke, GetAndUpdateOp::kAnd);
}
void IntrinsicCodeGeneratorARM64::VisitVarHandleGetAndBitwiseAnd(HInvoke* invoke) {
GenerateVarHandleGetAndUpdate(invoke, codegen_, GetAndUpdateOp::kAnd, std::memory_order_seq_cst);
}
void IntrinsicLocationsBuilderARM64::VisitVarHandleGetAndBitwiseAndAcquire(HInvoke* invoke) {
CreateVarHandleGetAndUpdateLocations(invoke, GetAndUpdateOp::kAnd);
}
void IntrinsicCodeGeneratorARM64::VisitVarHandleGetAndBitwiseAndAcquire(HInvoke* invoke) {
GenerateVarHandleGetAndUpdate(invoke, codegen_, GetAndUpdateOp::kAnd, std::memory_order_acquire);
}
void IntrinsicLocationsBuilderARM64::VisitVarHandleGetAndBitwiseAndRelease(HInvoke* invoke) {
CreateVarHandleGetAndUpdateLocations(invoke, GetAndUpdateOp::kAnd);
}
void IntrinsicCodeGeneratorARM64::VisitVarHandleGetAndBitwiseAndRelease(HInvoke* invoke) {
GenerateVarHandleGetAndUpdate(invoke, codegen_, GetAndUpdateOp::kAnd, std::memory_order_release);
}
void IntrinsicLocationsBuilderARM64::VisitVarHandleGetAndBitwiseOr(HInvoke* invoke) {
CreateVarHandleGetAndUpdateLocations(invoke, GetAndUpdateOp::kOr);
}
void IntrinsicCodeGeneratorARM64::VisitVarHandleGetAndBitwiseOr(HInvoke* invoke) {
GenerateVarHandleGetAndUpdate(invoke, codegen_, GetAndUpdateOp::kOr, std::memory_order_seq_cst);
}
void IntrinsicLocationsBuilderARM64::VisitVarHandleGetAndBitwiseOrAcquire(HInvoke* invoke) {
CreateVarHandleGetAndUpdateLocations(invoke, GetAndUpdateOp::kOr);
}
void IntrinsicCodeGeneratorARM64::VisitVarHandleGetAndBitwiseOrAcquire(HInvoke* invoke) {
GenerateVarHandleGetAndUpdate(invoke, codegen_, GetAndUpdateOp::kOr, std::memory_order_acquire);
}
void IntrinsicLocationsBuilderARM64::VisitVarHandleGetAndBitwiseOrRelease(HInvoke* invoke) {
CreateVarHandleGetAndUpdateLocations(invoke, GetAndUpdateOp::kOr);
}
void IntrinsicCodeGeneratorARM64::VisitVarHandleGetAndBitwiseOrRelease(HInvoke* invoke) {
GenerateVarHandleGetAndUpdate(invoke, codegen_, GetAndUpdateOp::kOr, std::memory_order_release);
}
void IntrinsicLocationsBuilderARM64::VisitVarHandleGetAndBitwiseXor(HInvoke* invoke) {
CreateVarHandleGetAndUpdateLocations(invoke, GetAndUpdateOp::kXor);
}
void IntrinsicCodeGeneratorARM64::VisitVarHandleGetAndBitwiseXor(HInvoke* invoke) {
GenerateVarHandleGetAndUpdate(invoke, codegen_, GetAndUpdateOp::kXor, std::memory_order_seq_cst);
}
void IntrinsicLocationsBuilderARM64::VisitVarHandleGetAndBitwiseXorAcquire(HInvoke* invoke) {
CreateVarHandleGetAndUpdateLocations(invoke, GetAndUpdateOp::kXor);
}
void IntrinsicCodeGeneratorARM64::VisitVarHandleGetAndBitwiseXorAcquire(HInvoke* invoke) {
GenerateVarHandleGetAndUpdate(invoke, codegen_, GetAndUpdateOp::kXor, std::memory_order_acquire);
}
void IntrinsicLocationsBuilderARM64::VisitVarHandleGetAndBitwiseXorRelease(HInvoke* invoke) {
CreateVarHandleGetAndUpdateLocations(invoke, GetAndUpdateOp::kXor);
}
void IntrinsicCodeGeneratorARM64::VisitVarHandleGetAndBitwiseXorRelease(HInvoke* invoke) {
GenerateVarHandleGetAndUpdate(invoke, codegen_, GetAndUpdateOp::kXor, std::memory_order_release);
}
void VarHandleSlowPathARM64::EmitByteArrayViewCode(CodeGenerator* codegen_in) {
DCHECK(GetByteArrayViewCheckLabel()->IsLinked());
CodeGeneratorARM64* codegen = down_cast<CodeGeneratorARM64*>(codegen_in);
MacroAssembler* masm = codegen->GetVIXLAssembler();
HInvoke* invoke = GetInvoke();
mirror::VarHandle::AccessModeTemplate access_mode_template = GetAccessModeTemplate();
DataType::Type value_type =
GetVarHandleExpectedValueType(invoke, /*expected_coordinates_count=*/ 2u);
DCHECK_NE(value_type, DataType::Type::kReference);
size_t size = DataType::Size(value_type);
DCHECK_GT(size, 1u);
Register varhandle = InputRegisterAt(invoke, 0);
Register object = InputRegisterAt(invoke, 1);
Register index = InputRegisterAt(invoke, 2);
MemberOffset class_offset = mirror::Object::ClassOffset();
MemberOffset array_length_offset = mirror::Array::LengthOffset();
MemberOffset data_offset = mirror::Array::DataOffset(Primitive::kPrimByte);
MemberOffset native_byte_order_offset = mirror::ByteArrayViewVarHandle::NativeByteOrderOffset();
__ Bind(GetByteArrayViewCheckLabel());
VarHandleTarget target = GetVarHandleTarget(invoke);
{
UseScratchRegisterScope temps(masm);
Register temp = temps.AcquireW();
Register temp2 = temps.AcquireW();
// The main path checked that the coordinateType0 is an array class that matches
// the class of the actual coordinate argument but it does not match the value type.
// Check if the `varhandle` references a ByteArrayViewVarHandle instance.
__ Ldr(temp, HeapOperand(varhandle, class_offset.Int32Value()));
codegen->LoadClassRootForIntrinsic(temp2, ClassRoot::kJavaLangInvokeByteArrayViewVarHandle);
__ Cmp(temp, temp2);
__ B(GetEntryLabel(), ne);
// Check for array index out of bounds.
__ Ldr(temp, HeapOperand(object, array_length_offset.Int32Value()));
__ Subs(temp, temp, index);
__ Ccmp(temp, size, NoFlag, hs); // If SUBS yields LO (C=false), keep the C flag clear.
__ B(GetEntryLabel(), lo);
// Construct the target.
__ Add(target.offset, index, data_offset.Int32Value());
// Alignment check. For unaligned access, go to the runtime.
DCHECK(IsPowerOfTwo(size));
if (size == 2u) {
__ Tbnz(target.offset, 0, GetEntryLabel());
} else {
__ Tst(target.offset, size - 1u);
__ B(GetEntryLabel(), ne);
}
// Byte order check. For native byte order return to the main path.
if (access_mode_template == mirror::VarHandle::AccessModeTemplate::kSet &&
IsConstantZeroBitPattern(invoke->InputAt(invoke->GetNumberOfArguments() - 1u))) {
// There is no reason to differentiate between native byte order and byte-swap
// for setting a zero bit pattern. Just return to the main path.
__ B(GetNativeByteOrderLabel());
return;
}
__ Ldr(temp, HeapOperand(varhandle, native_byte_order_offset.Int32Value()));
__ Cbnz(temp, GetNativeByteOrderLabel());
}
switch (access_mode_template) {
case mirror::VarHandle::AccessModeTemplate::kGet:
GenerateVarHandleGet(invoke, codegen, order_, /*byte_swap=*/ true);
break;
case mirror::VarHandle::AccessModeTemplate::kSet:
GenerateVarHandleSet(invoke, codegen, order_, /*byte_swap=*/ true);
break;
case mirror::VarHandle::AccessModeTemplate::kCompareAndSet:
case mirror::VarHandle::AccessModeTemplate::kCompareAndExchange:
GenerateVarHandleCompareAndSetOrExchange(
invoke, codegen, order_, return_success_, strong_, /*byte_swap=*/ true);
break;
case mirror::VarHandle::AccessModeTemplate::kGetAndUpdate:
GenerateVarHandleGetAndUpdate(
invoke, codegen, get_and_update_op_, order_, /*byte_swap=*/ true);
break;
}
__ B(GetExitLabel());
}
UNIMPLEMENTED_INTRINSIC(ARM64, StringStringIndexOf);
UNIMPLEMENTED_INTRINSIC(ARM64, StringStringIndexOfAfter);
UNIMPLEMENTED_INTRINSIC(ARM64, StringBufferAppend);
UNIMPLEMENTED_INTRINSIC(ARM64, StringBufferLength);
UNIMPLEMENTED_INTRINSIC(ARM64, StringBufferToString);
UNIMPLEMENTED_INTRINSIC(ARM64, StringBuilderAppendObject);
UNIMPLEMENTED_INTRINSIC(ARM64, StringBuilderAppendString);
UNIMPLEMENTED_INTRINSIC(ARM64, StringBuilderAppendCharSequence);
UNIMPLEMENTED_INTRINSIC(ARM64, StringBuilderAppendCharArray);
UNIMPLEMENTED_INTRINSIC(ARM64, StringBuilderAppendBoolean);
UNIMPLEMENTED_INTRINSIC(ARM64, StringBuilderAppendChar);
UNIMPLEMENTED_INTRINSIC(ARM64, StringBuilderAppendInt);
UNIMPLEMENTED_INTRINSIC(ARM64, StringBuilderAppendLong);
UNIMPLEMENTED_INTRINSIC(ARM64, StringBuilderAppendFloat);
UNIMPLEMENTED_INTRINSIC(ARM64, StringBuilderAppendDouble);
UNIMPLEMENTED_INTRINSIC(ARM64, StringBuilderLength);
UNIMPLEMENTED_INTRINSIC(ARM64, StringBuilderToString);
// 1.8.
UNIMPLEMENTED_INTRINSIC(ARM64, UnsafeGetAndAddInt)
UNIMPLEMENTED_INTRINSIC(ARM64, UnsafeGetAndAddLong)
UNIMPLEMENTED_INTRINSIC(ARM64, UnsafeGetAndSetInt)
UNIMPLEMENTED_INTRINSIC(ARM64, UnsafeGetAndSetLong)
UNIMPLEMENTED_INTRINSIC(ARM64, UnsafeGetAndSetObject)
UNIMPLEMENTED_INTRINSIC(ARM64, MethodHandleInvokeExact)
UNIMPLEMENTED_INTRINSIC(ARM64, MethodHandleInvoke)
UNREACHABLE_INTRINSICS(ARM64)
#undef __
} // namespace arm64
} // namespace art