v8/test/unittests/interpreter/interpreter-assembler-unittest.cc

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// Copyright 2015 the V8 project authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "test/unittests/interpreter/interpreter-assembler-unittest.h"
#include "src/codegen/code-factory.h"
#include "src/codegen/interface-descriptors.h"
#include "src/compiler/node-properties.h"
#include "src/compiler/node.h"
#include "src/execution/isolate.h"
#include "src/objects/objects-inl.h"
#include "test/unittests/compiler/compiler-test-utils.h"
#include "test/unittests/compiler/node-test-utils.h"
using ::testing::_;
using ::testing::Eq;
namespace c = v8::internal::compiler;
namespace v8 {
namespace internal {
namespace interpreter {
namespace interpreter_assembler_unittest {
InterpreterAssemblerTestState::InterpreterAssemblerTestState(
InterpreterAssemblerTest* test, Bytecode bytecode)
: compiler::CodeAssemblerState(
test->isolate(), test->zone(), InterpreterDispatchDescriptor{},
CodeKind::BYTECODE_HANDLER, Bytecodes::ToString(bytecode)) {}
const interpreter::Bytecode kBytecodes[] = {
#define DEFINE_BYTECODE(Name, ...) interpreter::Bytecode::k##Name,
BYTECODE_LIST(DEFINE_BYTECODE)
#undef DEFINE_BYTECODE
};
InterpreterAssemblerTest::InterpreterAssemblerForTest::
~InterpreterAssemblerForTest() {
// Tests don't necessarily read and write accumulator but
// InterpreterAssembler checks accumulator uses.
if (Bytecodes::ReadsAccumulator(bytecode())) {
GetAccumulator();
}
if (Bytecodes::WritesAccumulator(bytecode())) {
SetAccumulator(NullConstant());
}
Reland "[interpreter] Short Star bytecode" This is a reland of cf93071c91a932996a4df2e2d8880aca3cffbe28 Original change's description: > [interpreter] Short Star bytecode > > Design doc: > https://docs.google.com/document/d/1g_NExMT78II_KnIYNa9MvyPYIj23qAiFUEsyemY5KRk/edit > > This change adds 16 new interpreter opcodes, kStar0 through kStar15, so > that we can use a single byte to represent the common operation of > storing to a low-numbered register. This generally reduces the quantity > of bytecode generated on web sites by 8-9%. > > In order to not degrade speed, a couple of other changes are required: > > The existing lookahead logic to check for Star after certain other > bytecode handlers is updated to check for these new short Star codes > instead. Furthermore, that lookahead logic is updated to contain its own > copy of the dispatch jump rather than merging control flow with the > lookahead-failed case, to improve branch prediction. > > A bunch of constants use bytecode size in bytes as a proxy for the size > or complexity of a function, and are adjusted downward proportionally to > the decrease in generated bytecode size. > > Other small drive-by fix: update generate-bytecode-expectations to emit > \n instead of \r\n on Windows. > > Change-Id: I6307c2b0f5794a3a1088bb0fb94f6e1615441ed5 > Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2641180 > Reviewed-by: Ross McIlroy <rmcilroy@chromium.org> > Commit-Queue: Seth Brenith <seth.brenith@microsoft.com> > Cr-Commit-Position: refs/heads/master@{#72773} Change-Id: I1afb670c25694498b3989de615858f984a8c7f6f Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2698057 Commit-Queue: Seth Brenith <seth.brenith@microsoft.com> Reviewed-by: Ross McIlroy <rmcilroy@chromium.org> Reviewed-by: Mythri Alle <mythria@chromium.org> Cr-Commit-Position: refs/heads/master@{#72821}
2021-02-17 14:36:58 +00:00
if (Bytecodes::WritesImplicitRegister(bytecode())) {
StoreRegisterForShortStar(NullConstant(), IntPtrConstant(2));
}
}
Matcher<c::Node*> InterpreterAssemblerTest::InterpreterAssemblerForTest::IsLoad(
const Matcher<c::LoadRepresentation>& rep_matcher,
const Matcher<c::Node*>& base_matcher,
const Matcher<c::Node*>& index_matcher) {
return ::i::compiler::IsLoad(rep_matcher, base_matcher, index_matcher, _, _);
}
Matcher<c::Node*>
InterpreterAssemblerTest::InterpreterAssemblerForTest::IsLoadFromObject(
const Matcher<c::LoadRepresentation>& rep_matcher,
const Matcher<c::Node*>& base_matcher,
const Matcher<c::Node*>& index_matcher) {
return ::i::compiler::IsLoadFromObject(rep_matcher, base_matcher,
index_matcher, _, _);
}
Matcher<c::Node*>
InterpreterAssemblerTest::InterpreterAssemblerForTest::IsStore(
const Matcher<c::StoreRepresentation>& rep_matcher,
const Matcher<c::Node*>& base_matcher,
const Matcher<c::Node*>& index_matcher,
const Matcher<c::Node*>& value_matcher) {
return ::i::compiler::IsStore(rep_matcher, base_matcher, index_matcher,
value_matcher, _, _);
}
Matcher<c::Node*>
InterpreterAssemblerTest::InterpreterAssemblerForTest::IsWordNot(
const Matcher<c::Node*>& value_matcher) {
return kSystemPointerSize == 8
? IsWord64Xor(value_matcher, c::IsInt64Constant(-1))
: IsWord32Xor(value_matcher, c::IsInt32Constant(-1));
}
Matcher<c::Node*>
InterpreterAssemblerTest::InterpreterAssemblerForTest::IsUnsignedByteOperand(
int offset) {
return IsLoad(
MachineType::Uint8(),
c::IsParameter(InterpreterDispatchDescriptor::kBytecodeArray),
c::IsIntPtrAdd(
c::IsParameter(InterpreterDispatchDescriptor::kBytecodeOffset),
c::IsIntPtrConstant(offset)));
}
Matcher<c::Node*>
InterpreterAssemblerTest::InterpreterAssemblerForTest::IsSignedByteOperand(
int offset) {
return IsLoad(
MachineType::Int8(),
c::IsParameter(InterpreterDispatchDescriptor::kBytecodeArray),
c::IsIntPtrAdd(
c::IsParameter(InterpreterDispatchDescriptor::kBytecodeOffset),
c::IsIntPtrConstant(offset)));
}
Matcher<c::Node*>
InterpreterAssemblerTest::InterpreterAssemblerForTest::IsUnsignedShortOperand(
int offset) {
if (TargetSupportsUnalignedAccess()) {
return IsLoad(
MachineType::Uint16(),
c::IsParameter(InterpreterDispatchDescriptor::kBytecodeArray),
c::IsIntPtrAdd(
c::IsParameter(InterpreterDispatchDescriptor::kBytecodeOffset),
c::IsIntPtrConstant(offset)));
} else {
#if V8_TARGET_LITTLE_ENDIAN
const int kStep = -1;
const int kMsbOffset = 1;
#elif V8_TARGET_BIG_ENDIAN
const int kStep = 1;
const int kMsbOffset = 0;
#else
#error "Unknown Architecture"
#endif
Matcher<c::Node*> bytes[2];
for (int i = 0; i < static_cast<int>(arraysize(bytes)); i++) {
bytes[i] = IsLoad(
MachineType::Uint8(),
c::IsParameter(InterpreterDispatchDescriptor::kBytecodeArray),
c::IsIntPtrAdd(
c::IsParameter(InterpreterDispatchDescriptor::kBytecodeOffset),
c::IsIntPtrConstant(offset + kMsbOffset + kStep * i)));
}
return c::IsWord32Or(
c::IsWord32Shl(bytes[0], c::IsInt32Constant(kBitsPerByte)), bytes[1]);
}
}
Matcher<c::Node*>
InterpreterAssemblerTest::InterpreterAssemblerForTest::IsSignedShortOperand(
int offset) {
if (TargetSupportsUnalignedAccess()) {
return IsLoad(
MachineType::Int16(),
c::IsParameter(InterpreterDispatchDescriptor::kBytecodeArray),
c::IsIntPtrAdd(
c::IsParameter(InterpreterDispatchDescriptor::kBytecodeOffset),
c::IsIntPtrConstant(offset)));
} else {
#if V8_TARGET_LITTLE_ENDIAN
const int kStep = -1;
const int kMsbOffset = 1;
#elif V8_TARGET_BIG_ENDIAN
const int kStep = 1;
const int kMsbOffset = 0;
#else
#error "Unknown Architecture"
#endif
Matcher<c::Node*> bytes[2];
for (int i = 0; i < static_cast<int>(arraysize(bytes)); i++) {
bytes[i] = IsLoad(
(i == 0) ? MachineType::Int8() : MachineType::Uint8(),
c::IsParameter(InterpreterDispatchDescriptor::kBytecodeArray),
c::IsIntPtrAdd(
c::IsParameter(InterpreterDispatchDescriptor::kBytecodeOffset),
c::IsIntPtrConstant(offset + kMsbOffset + kStep * i)));
}
return c::IsWord32Or(
c::IsWord32Shl(bytes[0], c::IsInt32Constant(kBitsPerByte)), bytes[1]);
}
}
Matcher<c::Node*>
InterpreterAssemblerTest::InterpreterAssemblerForTest::IsUnsignedQuadOperand(
int offset) {
if (TargetSupportsUnalignedAccess()) {
return IsLoad(
MachineType::Uint32(),
c::IsParameter(InterpreterDispatchDescriptor::kBytecodeArray),
c::IsIntPtrAdd(
c::IsParameter(InterpreterDispatchDescriptor::kBytecodeOffset),
c::IsIntPtrConstant(offset)));
} else {
#if V8_TARGET_LITTLE_ENDIAN
const int kStep = -1;
const int kMsbOffset = 3;
#elif V8_TARGET_BIG_ENDIAN
const int kStep = 1;
const int kMsbOffset = 0;
#else
#error "Unknown Architecture"
#endif
Matcher<c::Node*> bytes[4];
for (int i = 0; i < static_cast<int>(arraysize(bytes)); i++) {
bytes[i] = IsLoad(
MachineType::Uint8(),
c::IsParameter(InterpreterDispatchDescriptor::kBytecodeArray),
c::IsIntPtrAdd(
c::IsParameter(InterpreterDispatchDescriptor::kBytecodeOffset),
c::IsIntPtrConstant(offset + kMsbOffset + kStep * i)));
}
return c::IsWord32Or(
c::IsWord32Shl(bytes[0], c::IsInt32Constant(3 * kBitsPerByte)),
c::IsWord32Or(
c::IsWord32Shl(bytes[1], c::IsInt32Constant(2 * kBitsPerByte)),
c::IsWord32Or(
c::IsWord32Shl(bytes[2], c::IsInt32Constant(1 * kBitsPerByte)),
bytes[3])));
}
}
Matcher<c::Node*>
InterpreterAssemblerTest::InterpreterAssemblerForTest::IsSignedQuadOperand(
int offset) {
if (TargetSupportsUnalignedAccess()) {
return IsLoad(
MachineType::Int32(),
c::IsParameter(InterpreterDispatchDescriptor::kBytecodeArray),
c::IsIntPtrAdd(
c::IsParameter(InterpreterDispatchDescriptor::kBytecodeOffset),
c::IsIntPtrConstant(offset)));
} else {
#if V8_TARGET_LITTLE_ENDIAN
const int kStep = -1;
int kMsbOffset = 3;
#elif V8_TARGET_BIG_ENDIAN
const int kStep = 1;
int kMsbOffset = 0;
#else
#error "Unknown Architecture"
#endif
Matcher<c::Node*> bytes[4];
for (int i = 0; i < static_cast<int>(arraysize(bytes)); i++) {
bytes[i] = IsLoad(
(i == 0) ? MachineType::Int8() : MachineType::Uint8(),
c::IsParameter(InterpreterDispatchDescriptor::kBytecodeArray),
c::IsIntPtrAdd(
c::IsParameter(InterpreterDispatchDescriptor::kBytecodeOffset),
c::IsIntPtrConstant(offset + kMsbOffset + kStep * i)));
}
return c::IsWord32Or(
c::IsWord32Shl(bytes[0], c::IsInt32Constant(3 * kBitsPerByte)),
c::IsWord32Or(
c::IsWord32Shl(bytes[1], c::IsInt32Constant(2 * kBitsPerByte)),
c::IsWord32Or(
c::IsWord32Shl(bytes[2], c::IsInt32Constant(1 * kBitsPerByte)),
bytes[3])));
}
}
Matcher<c::Node*>
InterpreterAssemblerTest::InterpreterAssemblerForTest::IsSignedOperand(
int offset, OperandSize operand_size) {
switch (operand_size) {
case OperandSize::kByte:
return IsSignedByteOperand(offset);
case OperandSize::kShort:
return IsSignedShortOperand(offset);
case OperandSize::kQuad:
return IsSignedQuadOperand(offset);
case OperandSize::kNone:
UNREACHABLE();
}
return nullptr;
}
Matcher<c::Node*>
InterpreterAssemblerTest::InterpreterAssemblerForTest::IsUnsignedOperand(
int offset, OperandSize operand_size) {
switch (operand_size) {
case OperandSize::kByte:
return IsUnsignedByteOperand(offset);
case OperandSize::kShort:
return IsUnsignedShortOperand(offset);
case OperandSize::kQuad:
return IsUnsignedQuadOperand(offset);
case OperandSize::kNone:
UNREACHABLE();
}
return nullptr;
}
Matcher<c::Node*>
InterpreterAssemblerTest::InterpreterAssemblerForTest::IsLoadRegisterOperand(
int offset, OperandSize operand_size) {
Matcher<c::Node*> reg_operand =
IsChangeInt32ToIntPtr(IsSignedOperand(offset, operand_size));
return IsBitcastWordToTagged(IsLoad(
MachineType::Pointer(), c::IsLoadParentFramePointer(),
c::IsWordShl(reg_operand, c::IsIntPtrConstant(kSystemPointerSizeLog2))));
}
TARGET_TEST_F(InterpreterAssemblerTest, BytecodeOperand) {
static const OperandScale kOperandScales[] = {
OperandScale::kSingle, OperandScale::kDouble, OperandScale::kQuadruple};
TRACED_FOREACH(interpreter::Bytecode, bytecode, kBytecodes) {
TRACED_FOREACH(interpreter::OperandScale, operand_scale, kOperandScales) {
InterpreterAssemblerTestState state(this, bytecode);
InterpreterAssemblerForTest m(&state, bytecode, operand_scale);
int number_of_operands =
interpreter::Bytecodes::NumberOfOperands(bytecode);
for (int i = 0; i < number_of_operands; i++) {
int offset = interpreter::Bytecodes::GetOperandOffset(bytecode, i,
operand_scale);
OperandType operand_type =
interpreter::Bytecodes::GetOperandType(bytecode, i);
OperandSize operand_size =
Bytecodes::SizeOfOperand(operand_type, operand_scale);
switch (interpreter::Bytecodes::GetOperandType(bytecode, i)) {
case interpreter::OperandType::kRegCount:
EXPECT_THAT(m.BytecodeOperandCount(i),
m.IsUnsignedOperand(offset, operand_size));
break;
case interpreter::OperandType::kFlag8:
EXPECT_THAT(m.BytecodeOperandFlag8(i),
m.IsUnsignedOperand(offset, operand_size));
break;
case interpreter::OperandType::kFlag16:
EXPECT_THAT(m.BytecodeOperandFlag16(i),
m.IsUnsignedOperand(offset, operand_size));
break;
case interpreter::OperandType::kIdx:
EXPECT_THAT(m.BytecodeOperandIdx(i),
c::IsChangeUint32ToWord(
m.IsUnsignedOperand(offset, operand_size)));
break;
case interpreter::OperandType::kNativeContextIndex:
EXPECT_THAT(m.BytecodeOperandNativeContextIndex(i),
c::IsChangeUint32ToWord(
m.IsUnsignedOperand(offset, operand_size)));
break;
case interpreter::OperandType::kUImm:
EXPECT_THAT(m.BytecodeOperandUImm(i),
m.IsUnsignedOperand(offset, operand_size));
break;
case interpreter::OperandType::kImm: {
EXPECT_THAT(m.BytecodeOperandImm(i),
m.IsSignedOperand(offset, operand_size));
break;
}
case interpreter::OperandType::kRuntimeId:
EXPECT_THAT(m.BytecodeOperandRuntimeId(i),
m.IsUnsignedOperand(offset, operand_size));
break;
case interpreter::OperandType::kIntrinsicId:
EXPECT_THAT(m.BytecodeOperandIntrinsicId(i),
m.IsUnsignedOperand(offset, operand_size));
break;
case interpreter::OperandType::kRegList:
case interpreter::OperandType::kReg:
case interpreter::OperandType::kRegPair:
case interpreter::OperandType::kRegOut:
case interpreter::OperandType::kRegOutList:
case interpreter::OperandType::kRegOutPair:
case interpreter::OperandType::kRegOutTriple:
EXPECT_THAT(m.LoadRegisterAtOperandIndex(i),
m.IsLoadRegisterOperand(offset, operand_size));
break;
case interpreter::OperandType::kNone:
UNREACHABLE();
}
}
}
}
}
TARGET_TEST_F(InterpreterAssemblerTest, GetContext) {
TRACED_FOREACH(interpreter::Bytecode, bytecode, kBytecodes) {
InterpreterAssemblerTestState state(this, bytecode);
InterpreterAssemblerForTest m(&state, bytecode);
EXPECT_THAT(
m.GetContext(),
IsBitcastWordToTagged(m.IsLoad(
MachineType::Pointer(), c::IsLoadParentFramePointer(),
c::IsIntPtrConstant(Register::current_context().ToOperand() *
kSystemPointerSize))));
}
}
TARGET_TEST_F(InterpreterAssemblerTest, LoadConstantPoolEntry) {
TRACED_FOREACH(interpreter::Bytecode, bytecode, kBytecodes) {
InterpreterAssemblerTestState state(this, bytecode);
InterpreterAssemblerForTest m(&state, bytecode);
{
TNode<IntPtrT> index = m.IntPtrConstant(2);
TNode<Object> load_constant = m.LoadConstantPoolEntry(index);
Matcher<c::Node*> constant_pool_matcher = m.IsLoadFromObject(
MachineType::AnyTagged(),
c::IsParameter(InterpreterDispatchDescriptor::kBytecodeArray),
c::IsIntPtrConstant(BytecodeArray::kConstantPoolOffset -
kHeapObjectTag));
EXPECT_THAT(load_constant,
m.IsLoadFromObject(
MachineType::AnyTagged(), constant_pool_matcher,
c::IsIntPtrConstant(FixedArray::OffsetOfElementAt(2) -
kHeapObjectTag)));
}
{
c::Node* index = m.UntypedParameter(2);
TNode<Object> load_constant =
m.LoadConstantPoolEntry(m.ReinterpretCast<IntPtrT>(index));
Matcher<c::Node*> constant_pool_matcher = m.IsLoadFromObject(
MachineType::AnyTagged(),
c::IsParameter(InterpreterDispatchDescriptor::kBytecodeArray),
c::IsIntPtrConstant(BytecodeArray::kConstantPoolOffset -
kHeapObjectTag));
EXPECT_THAT(
load_constant,
m.IsLoadFromObject(
MachineType::AnyTagged(), constant_pool_matcher,
c::IsIntPtrAdd(
c::IsIntPtrConstant(FixedArray::kHeaderSize - kHeapObjectTag),
c::IsWordShl(index, c::IsIntPtrConstant(kTaggedSizeLog2)))));
}
}
}
TARGET_TEST_F(InterpreterAssemblerTest, LoadObjectField) {
TRACED_FOREACH(interpreter::Bytecode, bytecode, kBytecodes) {
InterpreterAssemblerTestState state(this, bytecode);
InterpreterAssemblerForTest m(&state, bytecode);
TNode<HeapObject> object =
m.ReinterpretCast<HeapObject>(m.IntPtrConstant(0xDEADBEEF));
int offset = 16;
TNode<Object> load_field = m.LoadObjectField(object, offset);
EXPECT_THAT(
load_field,
m.IsLoadFromObject(MachineType::AnyTagged(), Eq(object),
c::IsIntPtrConstant(offset - kHeapObjectTag)));
}
}
TARGET_TEST_F(InterpreterAssemblerTest, CallRuntime2) {
TRACED_FOREACH(interpreter::Bytecode, bytecode, kBytecodes) {
InterpreterAssemblerTestState state(this, bytecode);
InterpreterAssemblerForTest m(&state, bytecode);
TNode<Object> arg1 = m.ReinterpretCast<Object>(m.Int32Constant(2));
TNode<Object> arg2 = m.ReinterpretCast<Object>(m.Int32Constant(3));
TNode<Object> context = m.ReinterpretCast<Object>(m.Int32Constant(4));
TNode<Object> call_runtime =
m.CallRuntime(Runtime::kAdd, context, arg1, arg2);
EXPECT_THAT(call_runtime,
c::IsCall(_, _, Eq(arg1), Eq(arg2), _, c::IsInt32Constant(2),
Eq(context), _, _));
}
}
TARGET_TEST_F(InterpreterAssemblerTest, CallRuntime) {
const int kResultSizes[] = {1, 2};
TRACED_FOREACH(interpreter::Bytecode, bytecode, kBytecodes) {
TRACED_FOREACH(int, result_size, kResultSizes) {
if (Bytecodes::IsCallRuntime(bytecode)) {
InterpreterAssemblerTestState state(this, bytecode);
InterpreterAssemblerForTest m(&state, bytecode);
Callable builtin =
CodeFactory::InterpreterCEntry(isolate(), result_size);
TNode<Uint32T> function_id = m.Uint32Constant(0);
InterpreterAssembler::RegListNodePair registers(m.IntPtrConstant(1),
m.Int32Constant(2));
TNode<Context> context = m.ReinterpretCast<Context>(m.Int32Constant(4));
Matcher<c::Node*> function_table = c::IsExternalConstant(
ExternalReference::runtime_function_table_address_for_unittests(
isolate()));
Matcher<c::Node*> function =
c::IsIntPtrAdd(function_table,
c::IsChangeUint32ToWord(c::IsInt32Mul(
Eq(function_id),
c::IsInt32Constant(sizeof(Runtime::Function)))));
Matcher<c::Node*> function_entry =
m.IsLoad(MachineType::Pointer(), function,
c::IsIntPtrConstant(offsetof(Runtime::Function, entry)));
c::Node* call_runtime =
m.CallRuntimeN(function_id, context, registers, result_size);
EXPECT_THAT(call_runtime,
c::IsCall(_, c::IsHeapConstant(builtin.code()),
Eq(registers.reg_count()),
Eq(registers.base_reg_location()), function_entry,
Eq(context), _, _));
}
}
}
}
TARGET_TEST_F(InterpreterAssemblerTest, LoadFeedbackVector) {
TRACED_FOREACH(interpreter::Bytecode, bytecode, kBytecodes) {
InterpreterAssemblerTestState state(this, bytecode);
InterpreterAssemblerForTest m(&state, bytecode);
TNode<HeapObject> feedback_vector = m.LoadFeedbackVector();
// Feedback vector is a phi node with two inputs. One of them is loading the
// feedback vector and the other is undefined constant (when feedback
// vectors aren't allocated). Find the input that loads feedback vector.
CHECK_EQ(static_cast<c::Node*>(feedback_vector)->opcode(),
i::compiler::IrOpcode::kPhi);
c::Node* value0 =
i::compiler::NodeProperties::GetValueInput(feedback_vector, 0);
c::Node* value1 =
i::compiler::NodeProperties::GetValueInput(feedback_vector, 1);
c::Node* load_feedback_vector = value0;
if (value0->opcode() == i::compiler::IrOpcode::kHeapConstant) {
load_feedback_vector = value1;
}
Matcher<c::Node*> load_function_matcher = IsBitcastWordToTagged(
m.IsLoad(MachineType::Pointer(), c::IsLoadParentFramePointer(),
c::IsIntPtrConstant(Register::function_closure().ToOperand() *
kSystemPointerSize)));
Matcher<c::Node*> load_vector_cell_matcher = m.IsLoadFromObject(
MachineType::TaggedPointer(), load_function_matcher,
c::IsIntPtrConstant(JSFunction::kFeedbackCellOffset - kHeapObjectTag));
EXPECT_THAT(load_feedback_vector,
m.IsLoadFromObject(
MachineType::TaggedPointer(), load_vector_cell_matcher,
c::IsIntPtrConstant(Cell::kValueOffset - kHeapObjectTag)));
}
}
} // namespace interpreter_assembler_unittest
} // namespace interpreter
} // namespace internal
} // namespace v8