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// Copyright 2014 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 "src/compiler/machine-operator-reducer.h"
#include <cmath>
#include <limits>
#include "src/base/bits.h"
#include "src/base/division-by-constant.h"
#include "src/base/ieee754.h"
#include "src/base/overflowing-math.h"
#include "src/compiler/diamond.h"
#include "src/compiler/graph.h"
#include "src/compiler/machine-graph.h"
#include "src/compiler/node-matchers.h"
#include "src/compiler/node-properties.h"
#include "src/compiler/opcodes.h"
#include "src/numbers/conversions-inl.h"
namespace v8 {
namespace internal {
namespace compiler {
// Some optimizations performed by the MachineOperatorReducer can be applied
// to both Word32 and Word64 operations. Those are implemented in a generic
// way to be reused for different word sizes.
// This class adapts a generic algorithm to Word32 operations.
class Word32Adapter {
public:
using IntNBinopMatcher = Int32BinopMatcher;
using UintNBinopMatcher = Uint32BinopMatcher;
using intN_t = int32_t;
// WORD_SIZE refers to the N for which this adapter specializes.
static constexpr std::size_t WORD_SIZE = 32;
explicit Word32Adapter(MachineOperatorReducer* reducer) : r_(reducer) {}
template <typename T>
static bool IsWordNAnd(const T& x) {
return x.IsWord32And();
}
template <typename T>
static bool IsWordNShl(const T& x) {
return x.IsWord32Shl();
}
template <typename T>
static bool IsWordNShr(const T& x) {
return x.IsWord32Shr();
}
template <typename T>
static bool IsWordNSar(const T& x) {
return x.IsWord32Sar();
}
template <typename T>
static bool IsWordNXor(const T& x) {
return x.IsWord32Xor();
}
template <typename T>
static bool IsIntNAdd(const T& x) {
return x.IsInt32Add();
}
template <typename T>
static bool IsIntNMul(const T& x) {
return x.IsInt32Mul();
}
const Operator* IntNAdd(MachineOperatorBuilder* machine) {
return machine->Int32Add();
}
Reduction ReplaceIntN(int32_t value) { return r_->ReplaceInt32(value); }
Reduction ReduceWordNAnd(Node* node) { return r_->ReduceWord32And(node); }
Reduction ReduceIntNAdd(Node* node) { return r_->ReduceInt32Add(node); }
Reduction TryMatchWordNRor(Node* node) { return r_->TryMatchWord32Ror(node); }
Node* IntNConstant(int32_t value) { return r_->Int32Constant(value); }
Node* UintNConstant(uint32_t value) { return r_->Uint32Constant(value); }
Node* WordNAnd(Node* lhs, Node* rhs) { return r_->Word32And(lhs, rhs); }
private:
MachineOperatorReducer* r_;
};
// Some optimizations performed by the MachineOperatorReducer can be applied
// to both Word32 and Word64 operations. Those are implemented in a generic
// way to be reused for different word sizes.
// This class adapts a generic algorithm to Word64 operations.
class Word64Adapter {
public:
using IntNBinopMatcher = Int64BinopMatcher;
using UintNBinopMatcher = Uint64BinopMatcher;
using intN_t = int64_t;
// WORD_SIZE refers to the N for which this adapter specializes.
static constexpr std::size_t WORD_SIZE = 64;
explicit Word64Adapter(MachineOperatorReducer* reducer) : r_(reducer) {}
template <typename T>
static bool IsWordNAnd(const T& x) {
return x.IsWord64And();
}
template <typename T>
static bool IsWordNShl(const T& x) {
return x.IsWord64Shl();
}
template <typename T>
static bool IsWordNShr(const T& x) {
return x.IsWord64Shr();
}
template <typename T>
static bool IsWordNSar(const T& x) {
return x.IsWord64Sar();
}
template <typename T>
static bool IsWordNXor(const T& x) {
return x.IsWord64Xor();
}
template <typename T>
static bool IsIntNAdd(const T& x) {
return x.IsInt64Add();
}
template <typename T>
static bool IsIntNMul(const T& x) {
return x.IsInt64Mul();
}
static const Operator* IntNAdd(MachineOperatorBuilder* machine) {
return machine->Int64Add();
}
Reduction ReplaceIntN(int64_t value) { return r_->ReplaceInt64(value); }
Reduction ReduceWordNAnd(Node* node) { return r_->ReduceWord64And(node); }
Reduction ReduceIntNAdd(Node* node) { return r_->ReduceInt64Add(node); }
Reduction TryMatchWordNRor(Node* node) {
// TODO(nicohartmann@): Add a MachineOperatorReducer::TryMatchWord64Ror.
return r_->NoChange();
}
Node* IntNConstant(int64_t value) { return r_->Int64Constant(value); }
Node* UintNConstant(uint64_t value) { return r_->Uint64Constant(value); }
Node* WordNAnd(Node* lhs, Node* rhs) { return r_->Word64And(lhs, rhs); }
private:
MachineOperatorReducer* r_;
};
namespace {
// TODO(jgruber): Consider replacing all uses of this function by
// std::numeric_limits<T>::quiet_NaN().
template <class T>
T SilenceNaN(T x) {
DCHECK(std::isnan(x));
// Do some calculation to make a signalling NaN quiet.
return x - x;
}
} // namespace
MachineOperatorReducer::MachineOperatorReducer(Editor* editor,
MachineGraph* mcgraph,
bool allow_signalling_nan)
: AdvancedReducer(editor),
mcgraph_(mcgraph),
allow_signalling_nan_(allow_signalling_nan) {}
MachineOperatorReducer::~MachineOperatorReducer() = default;
Node* MachineOperatorReducer::Float32Constant(volatile float value) {
return graph()->NewNode(common()->Float32Constant(value));
}
Node* MachineOperatorReducer::Float64Constant(volatile double value) {
return mcgraph()->Float64Constant(value);
}
Node* MachineOperatorReducer::Int32Constant(int32_t value) {
return mcgraph()->Int32Constant(value);
}
Node* MachineOperatorReducer::Int64Constant(int64_t value) {
return graph()->NewNode(common()->Int64Constant(value));
}
Node* MachineOperatorReducer::Float64Mul(Node* lhs, Node* rhs) {
return graph()->NewNode(machine()->Float64Mul(), lhs, rhs);
}
Node* MachineOperatorReducer::Float64PowHalf(Node* value) {
value =
graph()->NewNode(machine()->Float64Add(), Float64Constant(0.0), value);
Diamond d(graph(), common(),
graph()->NewNode(machine()->Float64LessThanOrEqual(), value,
Float64Constant(-V8_INFINITY)),
BranchHint::kFalse);
return d.Phi(MachineRepresentation::kFloat64, Float64Constant(V8_INFINITY),
graph()->NewNode(machine()->Float64Sqrt(), value));
}
Node* MachineOperatorReducer::Word32And(Node* lhs, Node* rhs) {
Node* const node = graph()->NewNode(machine()->Word32And(), lhs, rhs);
Reduction const reduction = ReduceWord32And(node);
return reduction.Changed() ? reduction.replacement() : node;
}
Node* MachineOperatorReducer::Word32Sar(Node* lhs, uint32_t rhs) {
if (rhs == 0) return lhs;
return graph()->NewNode(machine()->Word32Sar(), lhs, Uint32Constant(rhs));
}
Node* MachineOperatorReducer::Word32Shr(Node* lhs, uint32_t rhs) {
if (rhs == 0) return lhs;
return graph()->NewNode(machine()->Word32Shr(), lhs, Uint32Constant(rhs));
}
Node* MachineOperatorReducer::Word32Equal(Node* lhs, Node* rhs) {
return graph()->NewNode(machine()->Word32Equal(), lhs, rhs);
}
Node* MachineOperatorReducer::Word64And(Node* lhs, Node* rhs) {
Node* const node = graph()->NewNode(machine()->Word64And(), lhs, rhs);
Reduction const reduction = ReduceWord64And(node);
return reduction.Changed() ? reduction.replacement() : node;
}
Node* MachineOperatorReducer::Int32Add(Node* lhs, Node* rhs) {
Node* const node = graph()->NewNode(machine()->Int32Add(), lhs, rhs);
Reduction const reduction = ReduceInt32Add(node);
return reduction.Changed() ? reduction.replacement() : node;
}
Node* MachineOperatorReducer::Int32Sub(Node* lhs, Node* rhs) {
Node* const node = graph()->NewNode(machine()->Int32Sub(), lhs, rhs);
Reduction const reduction = ReduceInt32Sub(node);
return reduction.Changed() ? reduction.replacement() : node;
}
Node* MachineOperatorReducer::Int32Mul(Node* lhs, Node* rhs) {
return graph()->NewNode(machine()->Int32Mul(), lhs, rhs);
}
Node* MachineOperatorReducer::Int32Div(Node* dividend, int32_t divisor) {
DCHECK_NE(0, divisor);
DCHECK_NE(std::numeric_limits<int32_t>::min(), divisor);
base::MagicNumbersForDivision<uint32_t> const mag =
base::SignedDivisionByConstant(bit_cast<uint32_t>(divisor));
Node* quotient = graph()->NewNode(machine()->Int32MulHigh(), dividend,
Uint32Constant(mag.multiplier));
if (divisor > 0 && bit_cast<int32_t>(mag.multiplier) < 0) {
quotient = Int32Add(quotient, dividend);
} else if (divisor < 0 && bit_cast<int32_t>(mag.multiplier) > 0) {
quotient = Int32Sub(quotient, dividend);
}
return Int32Add(Word32Sar(quotient, mag.shift), Word32Shr(dividend, 31));
}
Node* MachineOperatorReducer::Uint32Div(Node* dividend, uint32_t divisor) {
DCHECK_LT(0u, divisor);
// If the divisor is even, we can avoid using the expensive fixup by shifting
// the dividend upfront.
unsigned const shift = base::bits::CountTrailingZeros(divisor);
dividend = Word32Shr(dividend, shift);
divisor >>= shift;
// Compute the magic number for the (shifted) divisor.
base::MagicNumbersForDivision<uint32_t> const mag =
base::UnsignedDivisionByConstant(divisor, shift);
Node* quotient = graph()->NewNode(machine()->Uint32MulHigh(), dividend,
Uint32Constant(mag.multiplier));
if (mag.add) {
DCHECK_LE(1u, mag.shift);
quotient = Word32Shr(
Int32Add(Word32Shr(Int32Sub(dividend, quotient), 1), quotient),
mag.shift - 1);
} else {
quotient = Word32Shr(quotient, mag.shift);
}
return quotient;
}
Node* MachineOperatorReducer::TruncateInt64ToInt32(Node* value) {
Node* const node = graph()->NewNode(machine()->TruncateInt64ToInt32(), value);
Reduction const reduction = ReduceTruncateInt64ToInt32(node);
return reduction.Changed() ? reduction.replacement() : node;
}
namespace {
bool ObjectsMayAlias(Node* a, Node* b) {
if (a != b) {
if (NodeProperties::IsFreshObject(b)) std::swap(a, b);
if (NodeProperties::IsFreshObject(a) &&
(NodeProperties::IsFreshObject(b) ||
b->opcode() == IrOpcode::kParameter ||
b->opcode() == IrOpcode::kLoadImmutable ||
IrOpcode::IsConstantOpcode(b->opcode()))) {
return false;
}
}
return true;
}
} // namespace
// Perform constant folding and strength reduction on machine operators.
Reduction MachineOperatorReducer::Reduce(Node* node) {
switch (node->opcode()) {
case IrOpcode::kProjection:
return ReduceProjection(ProjectionIndexOf(node->op()), node->InputAt(0));
case IrOpcode::kWord32And:
return ReduceWord32And(node);
case IrOpcode::kWord64And:
return ReduceWord64And(node);
case IrOpcode::kWord32Or:
return ReduceWord32Or(node);
case IrOpcode::kWord64Or:
return ReduceWord64Or(node);
case IrOpcode::kWord32Xor:
return ReduceWord32Xor(node);
case IrOpcode::kWord64Xor:
return ReduceWord64Xor(node);
case IrOpcode::kWord32Shl:
return ReduceWord32Shl(node);
case IrOpcode::kWord64Shl:
return ReduceWord64Shl(node);
case IrOpcode::kWord32Shr:
return ReduceWord32Shr(node);
case IrOpcode::kWord64Shr:
return ReduceWord64Shr(node);
case IrOpcode::kWord32Sar:
return ReduceWord32Sar(node);
case IrOpcode::kWord64Sar:
return ReduceWord64Sar(node);
case IrOpcode::kWord32Ror: {
Int32BinopMatcher m(node);
if (m.right().Is(0)) return Replace(m.left().node()); // x ror 0 => x
if (m.IsFoldable()) { // K ror K => K (K stands for arbitrary constants)
return ReplaceInt32(base::bits::RotateRight32(
m.left().ResolvedValue(), m.right().ResolvedValue() & 31));
}
break;
}
case IrOpcode::kWord32Equal: {
return ReduceWord32Equal(node);
}
case IrOpcode::kWord64Equal: {
Int64BinopMatcher m(node);
if (m.IsFoldable()) { // K == K => K (K stands for arbitrary constants)
return ReplaceBool(m.left().ResolvedValue() ==
m.right().ResolvedValue());
}
if (m.left().IsInt64Sub() && m.right().Is(0)) { // x - y == 0 => x == y
Int64BinopMatcher msub(m.left().node());
node->ReplaceInput(0, msub.left().node());
node->ReplaceInput(1, msub.right().node());
return Changed(node);
}
// TODO(turbofan): fold HeapConstant, ExternalReference, pointer compares
if (m.LeftEqualsRight()) return ReplaceBool(true); // x == x => true
// This is a workaround for not having escape analysis for wasm
// (machine-level) turbofan graphs.
if (!ObjectsMayAlias(m.left().node(), m.right().node())) {
return ReplaceBool(false);
}
break;
}
case IrOpcode::kInt32Add:
return ReduceInt32Add(node);
case IrOpcode::kInt64Add:
return ReduceInt64Add(node);
case IrOpcode::kInt32Sub:
return ReduceInt32Sub(node);
case IrOpcode::kInt64Sub:
return ReduceInt64Sub(node);
case IrOpcode::kInt32Mul: {
Int32BinopMatcher m(node);
if (m.right().Is(0)) return Replace(m.right().node()); // x * 0 => 0
if (m.right().Is(1)) return Replace(m.left().node()); // x * 1 => x
if (m.IsFoldable()) { // K * K => K (K stands for arbitrary constants)
return ReplaceInt32(base::MulWithWraparound(m.left().ResolvedValue(),
m.right().ResolvedValue()));
}
if (m.right().Is(-1)) { // x * -1 => 0 - x
node->ReplaceInput(0, Int32Constant(0));
node->ReplaceInput(1, m.left().node());
NodeProperties::ChangeOp(node, machine()->Int32Sub());
return Changed(node);
}
if (m.right().IsPowerOf2()) { // x * 2^n => x << n
node->ReplaceInput(1, Int32Constant(base::bits::WhichPowerOfTwo(
m.right().ResolvedValue())));
NodeProperties::ChangeOp(node, machine()->Word32Shl());
return Changed(node).FollowedBy(ReduceWord32Shl(node));
}
// (x * Int32Constant(a)) * Int32Constant(b)) => x * Int32Constant(a * b)
if (m.right().HasResolvedValue() && m.left().IsInt32Mul()) {
Int32BinopMatcher n(m.left().node());
if (n.right().HasResolvedValue() && m.OwnsInput(m.left().node())) {
node->ReplaceInput(
1, Int32Constant(base::MulWithWraparound(
m.right().ResolvedValue(), n.right().ResolvedValue())));
node->ReplaceInput(0, n.left().node());
return Changed(node);
}
}
break;
}
case IrOpcode::kInt32MulWithOverflow: {
Int32BinopMatcher m(node);
if (m.right().Is(2)) {
node->ReplaceInput(1, m.left().node());
NodeProperties::ChangeOp(node, machine()->Int32AddWithOverflow());
return Changed(node);
}
if (m.right().Is(-1)) {
node->ReplaceInput(0, Int32Constant(0));
node->ReplaceInput(1, m.left().node());
NodeProperties::ChangeOp(node, machine()->Int32SubWithOverflow());
return Changed(node);
}
break;
}
case IrOpcode::kInt64Mul:
return ReduceInt64Mul(node);
case IrOpcode::kInt32Div:
return ReduceInt32Div(node);
case IrOpcode::kUint32Div:
return ReduceUint32Div(node);
case IrOpcode::kInt32Mod:
return ReduceInt32Mod(node);
case IrOpcode::kUint32Mod:
return ReduceUint32Mod(node);
case IrOpcode::kInt32LessThan: {
Int32BinopMatcher m(node);
if (m.IsFoldable()) { // K < K => K (K stands for arbitrary constants)
return ReplaceBool(m.left().ResolvedValue() <
m.right().ResolvedValue());
}
if (m.LeftEqualsRight()) return ReplaceBool(false); // x < x => false
if (m.left().IsWord32Or() && m.right().Is(0)) {
// (x | K) < 0 => true or (K | x) < 0 => true iff K < 0
Int32BinopMatcher mleftmatcher(m.left().node());
if (mleftmatcher.left().IsNegative() ||
mleftmatcher.right().IsNegative()) {
return ReplaceBool(true);
}
}
return ReduceWord32Comparisons(node);
}
case IrOpcode::kInt32LessThanOrEqual: {
Int32BinopMatcher m(node);
if (m.IsFoldable()) { // K <= K => K (K stands for arbitrary constants)
return ReplaceBool(m.left().ResolvedValue() <=
m.right().ResolvedValue());
}
if (m.LeftEqualsRight()) return ReplaceBool(true); // x <= x => true
return ReduceWord32Comparisons(node);
}
case IrOpcode::kUint32LessThan: {
Uint32BinopMatcher m(node);
if (m.left().Is(kMaxUInt32)) return ReplaceBool(false); // M < x => false
if (m.right().Is(0)) return ReplaceBool(false); // x < 0 => false
if (m.IsFoldable()) { // K < K => K (K stands for arbitrary constants)
return ReplaceBool(m.left().ResolvedValue() <
m.right().ResolvedValue());
}
if (m.LeftEqualsRight()) return ReplaceBool(false); // x < x => false
if (m.left().IsWord32Sar() && m.right().HasResolvedValue()) {
Int32BinopMatcher mleft(m.left().node());
if (mleft.right().HasResolvedValue()) {
// (x >> K) < C => x < (C << K)
// when C < (M >> K)
const uint32_t c = m.right().ResolvedValue();
const uint32_t k = mleft.right().ResolvedValue() & 0x1F;
if (c < static_cast<uint32_t>(kMaxInt >> k)) {
node->ReplaceInput(0, mleft.left().node());
node->ReplaceInput(1, Uint32Constant(c << k));
return Changed(node);
}
// TODO(turbofan): else the comparison is always true.
}
}
return ReduceWord32Comparisons(node);
}
case IrOpcode::kUint32LessThanOrEqual: {
Uint32BinopMatcher m(node);
if (m.left().Is(0)) return ReplaceBool(true); // 0 <= x => true
if (m.right().Is(kMaxUInt32)) return ReplaceBool(true); // x <= M => true
if (m.IsFoldable()) { // K <= K => K (K stands for arbitrary constants)
return ReplaceBool(m.left().ResolvedValue() <=
m.right().ResolvedValue());
}
if (m.LeftEqualsRight()) return ReplaceBool(true); // x <= x => true
return ReduceWord32Comparisons(node);
}
case IrOpcode::kFloat32Sub: {
Float32BinopMatcher m(node);
if (allow_signalling_nan_ && m.right().Is(0) &&
(std::copysign(1.0, m.right().ResolvedValue()) > 0)) {
return Replace(m.left().node()); // x - 0 => x
}
if (m.right().IsNaN()) { // x - NaN => NaN
return ReplaceFloat32(SilenceNaN(m.right().ResolvedValue()));
}
if (m.left().IsNaN()) { // NaN - x => NaN
return ReplaceFloat32(SilenceNaN(m.left().ResolvedValue()));
}
if (m.IsFoldable()) { // L - R => (L - R)
return ReplaceFloat32(m.left().ResolvedValue() -
m.right().ResolvedValue());
}
if (allow_signalling_nan_ && m.left().IsMinusZero()) {
// -0.0 - round_down(-0.0 - R) => round_up(R)
if (machine()->Float32RoundUp().IsSupported() &&
m.right().IsFloat32RoundDown()) {
if (m.right().InputAt(0)->opcode() == IrOpcode::kFloat32Sub) {
Float32BinopMatcher mright0(m.right().InputAt(0));
if (mright0.left().IsMinusZero()) {
return Replace(graph()->NewNode(machine()->Float32RoundUp().op(),
mright0.right().node()));
}
}
}
// -0.0 - R => -R
node->RemoveInput(0);
NodeProperties::ChangeOp(node, machine()->Float32Neg());
return Changed(node);
}
break;
}
case IrOpcode::kFloat64Add: {
Float64BinopMatcher m(node);
if (m.right().IsNaN()) { // x + NaN => NaN
return ReplaceFloat64(SilenceNaN(m.right().ResolvedValue()));
}
if (m.left().IsNaN()) { // NaN + x => NaN
return ReplaceFloat64(SilenceNaN(m.left().ResolvedValue()));
}
if (m.IsFoldable()) { // K + K => K (K stands for arbitrary constants)
return ReplaceFloat64(m.left().ResolvedValue() +
m.right().ResolvedValue());
}
break;
}
case IrOpcode::kFloat64Sub: {
Float64BinopMatcher m(node);
if (allow_signalling_nan_ && m.right().Is(0) &&
(base::Double(m.right().ResolvedValue()).Sign() > 0)) {
return Replace(m.left().node()); // x - 0 => x
}
if (m.right().IsNaN()) { // x - NaN => NaN
return ReplaceFloat64(SilenceNaN(m.right().ResolvedValue()));
}
if (m.left().IsNaN()) { // NaN - x => NaN
return ReplaceFloat64(SilenceNaN(m.left().ResolvedValue()));
}
if (m.IsFoldable()) { // L - R => (L - R)
return ReplaceFloat64(m.left().ResolvedValue() -
m.right().ResolvedValue());
}
if (allow_signalling_nan_ && m.left().IsMinusZero()) {
// -0.0 - round_down(-0.0 - R) => round_up(R)
if (machine()->Float64RoundUp().IsSupported() &&
m.right().IsFloat64RoundDown()) {
if (m.right().InputAt(0)->opcode() == IrOpcode::kFloat64Sub) {
Float64BinopMatcher mright0(m.right().InputAt(0));
if (mright0.left().IsMinusZero()) {
return Replace(graph()->NewNode(machine()->Float64RoundUp().op(),
mright0.right().node()));
}
}
}
// -0.0 - R => -R
node->RemoveInput(0);
NodeProperties::ChangeOp(node, machine()->Float64Neg());
return Changed(node);
}
break;
}
case IrOpcode::kFloat64Mul: {
Float64BinopMatcher m(node);
if (allow_signalling_nan_ && m.right().Is(1))
return Replace(m.left().node()); // x * 1.0 => x
if (m.right().Is(-1)) { // x * -1.0 => -0.0 - x
node->ReplaceInput(0, Float64Constant(-0.0));
node->ReplaceInput(1, m.left().node());
NodeProperties::ChangeOp(node, machine()->Float64Sub());
return Changed(node);
}
if (m.right().IsNaN()) { // x * NaN => NaN
return ReplaceFloat64(SilenceNaN(m.right().ResolvedValue()));
}
if (m.IsFoldable()) { // K * K => K (K stands for arbitrary constants)
return ReplaceFloat64(m.left().ResolvedValue() *
m.right().ResolvedValue());
}
if (m.right().Is(2)) { // x * 2.0 => x + x
node->ReplaceInput(1, m.left().node());
NodeProperties::ChangeOp(node, machine()->Float64Add());
return Changed(node);
}
break;
}
case IrOpcode::kFloat64Div: {
Float64BinopMatcher m(node);
if (allow_signalling_nan_ && m.right().Is(1))
return Replace(m.left().node()); // x / 1.0 => x
// TODO(ahaas): We could do x / 1.0 = x if we knew that x is not an sNaN.
if (m.right().IsNaN()) { // x / NaN => NaN
return ReplaceFloat64(SilenceNaN(m.right().ResolvedValue()));
}
if (m.left().IsNaN()) { // NaN / x => NaN
return ReplaceFloat64(SilenceNaN(m.left().ResolvedValue()));
}
if (m.IsFoldable()) { // K / K => K (K stands for arbitrary constants)
return ReplaceFloat64(
base::Divide(m.left().ResolvedValue(), m.right().ResolvedValue()));
}
if (allow_signalling_nan_ && m.right().Is(-1)) { // x / -1.0 => -x
node->RemoveInput(1);
NodeProperties::ChangeOp(node, machine()->Float64Neg());
return Changed(node);
}
if (m.right().IsNormal() && m.right().IsPositiveOrNegativePowerOf2()) {
// All reciprocals of non-denormal powers of two can be represented
// exactly, so division by power of two can be reduced to
// multiplication by reciprocal, with the same result.
node->ReplaceInput(1, Float64Constant(1.0 / m.right().ResolvedValue()));
NodeProperties::ChangeOp(node, machine()->Float64Mul());
return Changed(node);
}
break;
}
case IrOpcode::kFloat64Mod: {
Float64BinopMatcher m(node);
if (m.right().Is(0)) { // x % 0 => NaN
return ReplaceFloat64(std::numeric_limits<double>::quiet_NaN());
}
if (m.right().IsNaN()) { // x % NaN => NaN
return ReplaceFloat64(SilenceNaN(m.right().ResolvedValue()));
}
if (m.left().IsNaN()) { // NaN % x => NaN
return ReplaceFloat64(SilenceNaN(m.left().ResolvedValue()));
}
if (m.IsFoldable()) { // K % K => K (K stands for arbitrary constants)
return ReplaceFloat64(
Modulo(m.left().ResolvedValue(), m.right().ResolvedValue()));
}
break;
}
case IrOpcode::kFloat64Acos: {
Float64Matcher m(node->InputAt(0));
if (m.HasResolvedValue())
return ReplaceFloat64(base::ieee754::acos(m.ResolvedValue()));
break;
}
case IrOpcode::kFloat64Acosh: {
Float64Matcher m(node->InputAt(0));
if (m.HasResolvedValue())
return ReplaceFloat64(base::ieee754::acosh(m.ResolvedValue()));
break;
}
case IrOpcode::kFloat64Asin: {
Float64Matcher m(node->InputAt(0));
if (m.HasResolvedValue())
return ReplaceFloat64(base::ieee754::asin(m.ResolvedValue()));
break;
}
case IrOpcode::kFloat64Asinh: {
Float64Matcher m(node->InputAt(0));
if (m.HasResolvedValue())
return ReplaceFloat64(base::ieee754::asinh(m.ResolvedValue()));
break;
}
case IrOpcode::kFloat64Atan: {
Float64Matcher m(node->InputAt(0));
if (m.HasResolvedValue())
return ReplaceFloat64(base::ieee754::atan(m.ResolvedValue()));
break;
}
case IrOpcode::kFloat64Atanh: {
Float64Matcher m(node->InputAt(0));
if (m.HasResolvedValue())
return ReplaceFloat64(base::ieee754::atanh(m.ResolvedValue()));
break;
}
case IrOpcode::kFloat64Atan2: {
Float64BinopMatcher m(node);
if (m.right().IsNaN()) {
return ReplaceFloat64(SilenceNaN(m.right().ResolvedValue()));
}
if (m.left().IsNaN()) {
return ReplaceFloat64(SilenceNaN(m.left().ResolvedValue()));
}
if (m.IsFoldable()) {
return ReplaceFloat64(base::ieee754::atan2(m.left().ResolvedValue(),
m.right().ResolvedValue()));
}
break;
}
case IrOpcode::kFloat64Cbrt: {
Float64Matcher m(node->InputAt(0));
if (m.HasResolvedValue())
return ReplaceFloat64(base::ieee754::cbrt(m.ResolvedValue()));
break;
}
case IrOpcode::kFloat64Cos: {
Float64Matcher m(node->InputAt(0));
if (m.HasResolvedValue())
return ReplaceFloat64(base::ieee754::cos(m.ResolvedValue()));
break;
}
case IrOpcode::kFloat64Cosh: {
Float64Matcher m(node->InputAt(0));
if (m.HasResolvedValue())
return ReplaceFloat64(base::ieee754::cosh(m.ResolvedValue()));
break;
}
case IrOpcode::kFloat64Exp: {
Float64Matcher m(node->InputAt(0));
if (m.HasResolvedValue())
return ReplaceFloat64(base::ieee754::exp(m.ResolvedValue()));
break;
}
case IrOpcode::kFloat64Expm1: {
Float64Matcher m(node->InputAt(0));
if (m.HasResolvedValue())
return ReplaceFloat64(base::ieee754::expm1(m.ResolvedValue()));
break;
}
case IrOpcode::kFloat64Log: {
Float64Matcher m(node->InputAt(0));
if (m.HasResolvedValue())
return ReplaceFloat64(base::ieee754::log(m.ResolvedValue()));
break;
}
case IrOpcode::kFloat64Log1p: {
Float64Matcher m(node->InputAt(0));
if (m.HasResolvedValue())
return ReplaceFloat64(base::ieee754::log1p(m.ResolvedValue()));
break;
}
case IrOpcode::kFloat64Log10: {
Float64Matcher m(node->InputAt(0));
if (m.HasResolvedValue())
return ReplaceFloat64(base::ieee754::log10(m.ResolvedValue()));
break;
}
case IrOpcode::kFloat64Log2: {
Float64Matcher m(node->InputAt(0));
if (m.HasResolvedValue())
return ReplaceFloat64(base::ieee754::log2(m.ResolvedValue()));
break;
}
case IrOpcode::kFloat64Pow: {
Float64BinopMatcher m(node);
if (m.IsFoldable()) {
return ReplaceFloat64(base::ieee754::pow(m.left().ResolvedValue(),
m.right().ResolvedValue()));
} else if (m.right().Is(0.0)) { // x ** +-0.0 => 1.0
return ReplaceFloat64(1.0);
} else if (m.right().Is(2.0)) { // x ** 2.0 => x * x
node->ReplaceInput(1, m.left().node());
NodeProperties::ChangeOp(node, machine()->Float64Mul());
return Changed(node);
} else if (m.right().Is(0.5)) {
// x ** 0.5 => if x <= -Infinity then Infinity else sqrt(0.0 + x)
return Replace(Float64PowHalf(m.left().node()));
}
break;
}
case IrOpcode::kFloat64Sin: {
Float64Matcher m(node->InputAt(0));
if (m.HasResolvedValue())
return ReplaceFloat64(base::ieee754::sin(m.ResolvedValue()));
break;
}
case IrOpcode::kFloat64Sinh: {
Float64Matcher m(node->InputAt(0));
if (m.HasResolvedValue())
return ReplaceFloat64(base::ieee754::sinh(m.ResolvedValue()));
break;
}
case IrOpcode::kFloat64Tan: {
Float64Matcher m(node->InputAt(0));
if (m.HasResolvedValue())
return ReplaceFloat64(base::ieee754::tan(m.ResolvedValue()));
break;
}
case IrOpcode::kFloat64Tanh: {
Float64Matcher m(node->InputAt(0));
if (m.HasResolvedValue())
return ReplaceFloat64(base::ieee754::tanh(m.ResolvedValue()));
break;
}
case IrOpcode::kChangeFloat32ToFloat64: {
Float32Matcher m(node->InputAt(0));
if (m.HasResolvedValue()) {
if (!allow_signalling_nan_ && std::isnan(m.ResolvedValue())) {
return ReplaceFloat64(SilenceNaN(m.ResolvedValue()));
}
return ReplaceFloat64(m.ResolvedValue());
}
break;
}
case IrOpcode::kChangeFloat64ToInt32: {
Float64Matcher m(node->InputAt(0));
if (m.HasResolvedValue())
return ReplaceInt32(FastD2IChecked(m.ResolvedValue()));
if (m.IsChangeInt32ToFloat64()) return Replace(m.node()->InputAt(0));
break;
}
case IrOpcode::kChangeFloat64ToInt64: {
Float64Matcher m(node->InputAt(0));
if (m.HasResolvedValue())
return ReplaceInt64(static_cast<int64_t>(m.ResolvedValue()));
if (m.IsChangeInt64ToFloat64()) return Replace(m.node()->InputAt(0));
break;
}
case IrOpcode::kChangeFloat64ToUint32: {
Float64Matcher m(node->InputAt(0));
if (m.HasResolvedValue())
return ReplaceInt32(FastD2UI(m.ResolvedValue()));
if (m.IsChangeUint32ToFloat64()) return Replace(m.node()->InputAt(0));
break;
}
case IrOpcode::kChangeInt32ToFloat64: {
Int32Matcher m(node->InputAt(0));
if (m.HasResolvedValue())
return ReplaceFloat64(FastI2D(m.ResolvedValue()));
break;
}
case IrOpcode::kBitcastWord32ToWord64: {
Int32Matcher m(node->InputAt(0));
if (m.HasResolvedValue()) return ReplaceInt64(m.ResolvedValue());
break;
}
case IrOpcode::kChangeInt32ToInt64: {
Int32Matcher m(node->InputAt(0));
if (m.HasResolvedValue()) return ReplaceInt64(m.ResolvedValue());
break;
}
case IrOpcode::kChangeInt64ToFloat64: {
Int64Matcher m(node->InputAt(0));
if (m.HasResolvedValue())
return ReplaceFloat64(static_cast<double>(m.ResolvedValue()));
if (m.IsChangeFloat64ToInt64()) return Replace(m.node()->InputAt(0));
break;
}
case IrOpcode::kChangeUint32ToFloat64: {
Uint32Matcher m(node->InputAt(0));
if (m.HasResolvedValue())
return ReplaceFloat64(FastUI2D(m.ResolvedValue()));
break;
}
case IrOpcode::kChangeUint32ToUint64: {
Uint32Matcher m(node->InputAt(0));
if (m.HasResolvedValue())
return ReplaceInt64(static_cast<uint64_t>(m.ResolvedValue()));
break;
}
case IrOpcode::kTruncateFloat64ToWord32: {
Float64Matcher m(node->InputAt(0));
if (m.HasResolvedValue())
return ReplaceInt32(DoubleToInt32(m.ResolvedValue()));
if (m.IsChangeInt32ToFloat64()) return Replace(m.node()->InputAt(0));
return NoChange();
}
case IrOpcode::kTruncateInt64ToInt32:
return ReduceTruncateInt64ToInt32(node);
case IrOpcode::kTruncateFloat64ToFloat32: {
Float64Matcher m(node->InputAt(0));
if (m.HasResolvedValue()) {
if (!allow_signalling_nan_ && m.IsNaN()) {
return ReplaceFloat32(DoubleToFloat32(SilenceNaN(m.ResolvedValue())));
}
return ReplaceFloat32(DoubleToFloat32(m.ResolvedValue()));
}
if (allow_signalling_nan_ && m.IsChangeFloat32ToFloat64())
return Replace(m.node()->InputAt(0));
break;
}
case IrOpcode::kRoundFloat64ToInt32: {
Float64Matcher m(node->InputAt(0));
if (m.HasResolvedValue()) {
return ReplaceInt32(DoubleToInt32(m.ResolvedValue()));
}
if (m.IsChangeInt32ToFloat64()) return Replace(m.node()->InputAt(0));
break;
}
case IrOpcode::kFloat64InsertLowWord32:
return ReduceFloat64InsertLowWord32(node);
case IrOpcode::kFloat64InsertHighWord32:
return ReduceFloat64InsertHighWord32(node);
case IrOpcode::kStore:
case IrOpcode::kUnalignedStore:
return ReduceStore(node);
case IrOpcode::kFloat64Equal:
case IrOpcode::kFloat64LessThan:
case IrOpcode::kFloat64LessThanOrEqual:
return ReduceFloat64Compare(node);
case IrOpcode::kFloat64RoundDown:
return ReduceFloat64RoundDown(node);
case IrOpcode::kBitcastTaggedToWord:
case IrOpcode::kBitcastTaggedToWordForTagAndSmiBits: {
NodeMatcher m(node->InputAt(0));
if (m.IsBitcastWordToTaggedSigned()) {
RelaxEffectsAndControls(node);
return Replace(m.InputAt(0));
}
break;
}
case IrOpcode::kBranch:
case IrOpcode::kDeoptimizeIf:
case IrOpcode::kDeoptimizeUnless:
case IrOpcode::kTrapIf:
case IrOpcode::kTrapUnless:
return ReduceConditional(node);
case IrOpcode::kInt64LessThan: {
Int64BinopMatcher m(node);
if (m.IsFoldable()) { // K < K => K (K stands for arbitrary constants)
return ReplaceBool(m.left().ResolvedValue() <
m.right().ResolvedValue());
}
return ReduceWord64Comparisons(node);
}
case IrOpcode::kInt64LessThanOrEqual: {
Int64BinopMatcher m(node);
if (m.IsFoldable()) { // K <= K => K (K stands for arbitrary constants)
return ReplaceBool(m.left().ResolvedValue() <=
m.right().ResolvedValue());
}
return ReduceWord64Comparisons(node);
}
case IrOpcode::kUint64LessThan: {
Uint64BinopMatcher m(node);
if (m.IsFoldable()) { // K < K => K (K stands for arbitrary constants)
return ReplaceBool(m.left().ResolvedValue() <
m.right().ResolvedValue());
}
return ReduceWord64Comparisons(node);
}
case IrOpcode::kUint64LessThanOrEqual: {
Uint64BinopMatcher m(node);
if (m.IsFoldable()) { // K <= K => K (K stands for arbitrary constants)
return ReplaceBool(m.left().ResolvedValue() <=
m.right().ResolvedValue());
}
return ReduceWord64Comparisons(node);
}
default:
break;
}
return NoChange();
}
Reduction MachineOperatorReducer::ReduceTruncateInt64ToInt32(Node* node) {
Int64Matcher m(node->InputAt(0));
if (m.HasResolvedValue())
return ReplaceInt32(static_cast<int32_t>(m.ResolvedValue()));
if (m.IsChangeInt32ToInt64()) return Replace(m.node()->InputAt(0));
return NoChange();
}
Reduction MachineOperatorReducer::ReduceInt32Add(Node* node) {
DCHECK_EQ(IrOpcode::kInt32Add, node->opcode());
Int32BinopMatcher m(node);
if (m.right().Is(0)) return Replace(m.left().node()); // x + 0 => x
if (m.IsFoldable()) { // K + K => K (K stands for arbitrary constants)
return ReplaceInt32(base::AddWithWraparound(m.left().ResolvedValue(),
m.right().ResolvedValue()));
}
if (m.left().IsInt32Sub()) {
Int32BinopMatcher mleft(m.left().node());
if (mleft.left().Is(0)) { // (0 - x) + y => y - x
node->ReplaceInput(0, m.right().node());
node->ReplaceInput(1, mleft.right().node());
NodeProperties::ChangeOp(node, machine()->Int32Sub());
return Changed(node).FollowedBy(ReduceInt32Sub(node));
}
}
if (m.right().IsInt32Sub()) {
Int32BinopMatcher mright(m.right().node());
if (mright.left().Is(0)) { // y + (0 - x) => y - x
node->ReplaceInput(1, mright.right().node());
NodeProperties::ChangeOp(node, machine()->Int32Sub());
return Changed(node).FollowedBy(ReduceInt32Sub(node));
}
}
// (x + Int32Constant(a)) + Int32Constant(b)) => x + Int32Constant(a + b)
if (m.right().HasResolvedValue() && m.left().IsInt32Add()) {
Int32BinopMatcher n(m.left().node());
if (n.right().HasResolvedValue() && m.OwnsInput(m.left().node())) {
node->ReplaceInput(
1, Int32Constant(base::AddWithWraparound(m.right().ResolvedValue(),
n.right().ResolvedValue())));
node->ReplaceInput(0, n.left().node());
return Changed(node);
}
}
return NoChange();
}
Reduction MachineOperatorReducer::ReduceInt64Add(Node* node) {
DCHECK_EQ(IrOpcode::kInt64Add, node->opcode());
Int64BinopMatcher m(node);
if (m.right().Is(0)) return Replace(m.left().node()); // x + 0 => 0
if (m.IsFoldable()) {
return ReplaceInt64(base::AddWithWraparound(m.left().ResolvedValue(),
m.right().ResolvedValue()));
}
// (x + Int64Constant(a)) + Int64Constant(b)) => x + Int64Constant(a + b)
if (m.right().HasResolvedValue() && m.left().IsInt64Add()) {
Int64BinopMatcher n(m.left().node());
if (n.right().HasResolvedValue() && m.OwnsInput(m.left().node())) {
node->ReplaceInput(
1, Int64Constant(base::AddWithWraparound(m.right().ResolvedValue(),
n.right().ResolvedValue())));
node->ReplaceInput(0, n.left().node());
return Changed(node);
}
}
return NoChange();
}
Reduction MachineOperatorReducer::ReduceInt32Sub(Node* node) {
DCHECK_EQ(IrOpcode::kInt32Sub, node->opcode());
Int32BinopMatcher m(node);
if (m.right().Is(0)) return Replace(m.left().node()); // x - 0 => x
if (m.IsFoldable()) { // K - K => K (K stands for arbitrary constants)
return ReplaceInt32(base::SubWithWraparound(m.left().ResolvedValue(),
m.right().ResolvedValue()));
}
if (m.LeftEqualsRight()) return ReplaceInt32(0); // x - x => 0
if (m.right().HasResolvedValue()) { // x - K => x + -K
node->ReplaceInput(
1,
Int32Constant(base::NegateWithWraparound(m.right().ResolvedValue())));
NodeProperties::ChangeOp(node, machine()->Int32Add());
return Changed(node).FollowedBy(ReduceInt32Add(node));
}
return NoChange();
}
Reduction MachineOperatorReducer::ReduceInt64Sub(Node* node) {
DCHECK_EQ(IrOpcode::kInt64Sub, node->opcode());
Int64BinopMatcher m(node);
if (m.right().Is(0)) return Replace(m.left().node()); // x - 0 => x
if (m.IsFoldable()) { // K - K => K (K stands for arbitrary constants)
return ReplaceInt64(base::SubWithWraparound(m.left().ResolvedValue(),
m.right().ResolvedValue()));
}
if (m.LeftEqualsRight()) return Replace(Int64Constant(0)); // x - x => 0
if (m.right().HasResolvedValue()) { // x - K => x + -K
node->ReplaceInput(
1,
Int64Constant(base::NegateWithWraparound(m.right().ResolvedValue())));
NodeProperties::ChangeOp(node, machine()->Int64Add());
return Changed(node).FollowedBy(ReduceInt64Add(node));
}
return NoChange();
}
Reduction MachineOperatorReducer::ReduceInt64Mul(Node* node) {
DCHECK_EQ(IrOpcode::kInt64Mul, node->opcode());
Int64BinopMatcher m(node);
if (m.right().Is(0)) return Replace(m.right().node()); // x * 0 => 0
if (m.right().Is(1)) return Replace(m.left().node()); // x * 1 => x
if (m.IsFoldable()) { // K * K => K (K stands for arbitrary constants)
return ReplaceInt64(base::MulWithWraparound(m.left().ResolvedValue(),
m.right().ResolvedValue()));
}
if (m.right().Is(-1)) { // x * -1 => 0 - x
node->ReplaceInput(0, Int64Constant(0));
node->ReplaceInput(1, m.left().node());
NodeProperties::ChangeOp(node, machine()->Int64Sub());
return Changed(node);
}
if (m.right().IsPowerOf2()) { // x * 2^n => x << n
node->ReplaceInput(
1,
Int64Constant(base::bits::WhichPowerOfTwo(m.right().ResolvedValue())));
NodeProperties::ChangeOp(node, machine()->Word64Shl());
return Changed(node).FollowedBy(ReduceWord64Shl(node));
}
// (x * Int64Constant(a)) * Int64Constant(b)) => x * Int64Constant(a * b)
if (m.right().HasResolvedValue() && m.left().IsInt64Mul()) {
Int64BinopMatcher n(m.left().node());
if (n.right().HasResolvedValue() && m.OwnsInput(m.left().node())) {
node->ReplaceInput(
1, Int64Constant(base::MulWithWraparound(m.right().ResolvedValue(),
n.right().ResolvedValue())));
node->ReplaceInput(0, n.left().node());
return Changed(node);
}
}
return NoChange();
}
Reduction MachineOperatorReducer::ReduceInt32Div(Node* node) {
Int32BinopMatcher m(node);
if (m.left().Is(0)) return Replace(m.left().node()); // 0 / x => 0
if (m.right().Is(0)) return Replace(m.right().node()); // x / 0 => 0
if (m.right().Is(1)) return Replace(m.left().node()); // x / 1 => x
if (m.IsFoldable()) { // K / K => K (K stands for arbitrary constants)
return ReplaceInt32(base::bits::SignedDiv32(m.left().ResolvedValue(),
m.right().ResolvedValue()));
}
if (m.LeftEqualsRight()) { // x / x => x != 0
Node* const zero = Int32Constant(0);
return Replace(Word32Equal(Word32Equal(m.left().node(), zero), zero));
}
if (m.right().Is(-1)) { // x / -1 => 0 - x
node->ReplaceInput(0, Int32Constant(0));
node->ReplaceInput(1, m.left().node());
node->TrimInputCount(2);
NodeProperties::ChangeOp(node, machine()->Int32Sub());
return Changed(node);
}
if (m.right().HasResolvedValue()) {
int32_t const divisor = m.right().ResolvedValue();
Node* const dividend = m.left().node();
Node* quotient = dividend;
if (base::bits::IsPowerOfTwo(Abs(divisor))) {
uint32_t const shift = base::bits::WhichPowerOfTwo(Abs(divisor));
DCHECK_NE(0u, shift);
if (shift > 1) {
quotient = Word32Sar(quotient, 31);
}
quotient = Int32Add(Word32Shr(quotient, 32u - shift), dividend);
quotient = Word32Sar(quotient, shift);
} else {
quotient = Int32Div(quotient, Abs(divisor));
}
if (divisor < 0) {
node->ReplaceInput(0, Int32Constant(0));
node->ReplaceInput(1, quotient);
node->TrimInputCount(2);
NodeProperties::ChangeOp(node, machine()->Int32Sub());
return Changed(node);
}
return Replace(quotient);
}
return NoChange();
}
Reduction MachineOperatorReducer::ReduceUint32Div(Node* node) {
Uint32BinopMatcher m(node);
if (m.left().Is(0)) return Replace(m.left().node()); // 0 / x => 0
if (m.right().Is(0)) return Replace(m.right().node()); // x / 0 => 0
if (m.right().Is(1)) return Replace(m.left().node()); // x / 1 => x
if (m.IsFoldable()) { // K / K => K (K stands for arbitrary constants)
return ReplaceUint32(base::bits::UnsignedDiv32(m.left().ResolvedValue(),
m.right().ResolvedValue()));
}
if (m.LeftEqualsRight()) { // x / x => x != 0
Node* const zero = Int32Constant(0);
return Replace(Word32Equal(Word32Equal(m.left().node(), zero), zero));
}
if (m.right().HasResolvedValue()) {
Node* const dividend = m.left().node();
uint32_t const divisor = m.right().ResolvedValue();
if (base::bits::IsPowerOfTwo(divisor)) { // x / 2^n => x >> n
node->ReplaceInput(1, Uint32Constant(base::bits::WhichPowerOfTwo(
m.right().ResolvedValue())));
node->TrimInputCount(2);
NodeProperties::ChangeOp(node, machine()->Word32Shr());
return Changed(node);
} else {
return Replace(Uint32Div(dividend, divisor));
}
}
return NoChange();
}
Reduction MachineOperatorReducer::ReduceInt32Mod(Node* node) {
Int32BinopMatcher m(node);
if (m.left().Is(0)) return Replace(m.left().node()); // 0 % x => 0
if (m.right().Is(0)) return Replace(m.right().node()); // x % 0 => 0
if (m.right().Is(1)) return ReplaceInt32(0); // x % 1 => 0
if (m.right().Is(-1)) return ReplaceInt32(0); // x % -1 => 0
if (m.LeftEqualsRight()) return ReplaceInt32(0); // x % x => 0
if (m.IsFoldable()) { // K % K => K (K stands for arbitrary constants)
return ReplaceInt32(base::bits::SignedMod32(m.left().ResolvedValue(),
m.right().ResolvedValue()));
}
if (m.right().HasResolvedValue()) {
Node* const dividend = m.left().node();
uint32_t const divisor = Abs(m.right().ResolvedValue());
if (base::bits::IsPowerOfTwo(divisor)) {
uint32_t const mask = divisor - 1;
Node* const zero = Int32Constant(0);
Diamond d(graph(), common(),
graph()->NewNode(machine()->Int32LessThan(), dividend, zero),
BranchHint::kFalse);
return Replace(
d.Phi(MachineRepresentation::kWord32,
Int32Sub(zero, Word32And(Int32Sub(zero, dividend), mask)),
Word32And(dividend, mask)));
} else {
Node* quotient = Int32Div(dividend, divisor);
DCHECK_EQ(dividend, node->InputAt(0));
node->ReplaceInput(1, Int32Mul(quotient, Int32Constant(divisor)));
node->TrimInputCount(2);
NodeProperties::ChangeOp(node, machine()->Int32Sub());
}
return Changed(node);
}
return NoChange();
}
Reduction MachineOperatorReducer::ReduceUint32Mod(Node* node) {
Uint32BinopMatcher m(node);
if (m.left().Is(0)) return Replace(m.left().node()); // 0 % x => 0
if (m.right().Is(0)) return Replace(m.right().node()); // x % 0 => 0
if (m.right().Is(1)) return ReplaceUint32(0); // x % 1 => 0
if (m.LeftEqualsRight()) return ReplaceInt32(0); // x % x => 0
if (m.IsFoldable()) { // K % K => K (K stands for arbitrary constants)
return ReplaceUint32(base::bits::UnsignedMod32(m.left().ResolvedValue(),
m.right().ResolvedValue()));
}
if (m.right().HasResolvedValue()) {
Node* const dividend = m.left().node();
uint32_t const divisor = m.right().ResolvedValue();
if (base::bits::IsPowerOfTwo(divisor)) { // x % 2^n => x & 2^n-1
node->ReplaceInput(1, Uint32Constant(m.right().ResolvedValue() - 1));
node->TrimInputCount(2);
NodeProperties::ChangeOp(node, machine()->Word32And());
} else {
Node* quotient = Uint32Div(dividend, divisor);
DCHECK_EQ(dividend, node->InputAt(0));
node->ReplaceInput(1, Int32Mul(quotient, Uint32Constant(divisor)));
node->TrimInputCount(2);
NodeProperties::ChangeOp(node, machine()->Int32Sub());
}
return Changed(node);
}
return NoChange();
}
Reduction MachineOperatorReducer::ReduceStore(Node* node) {
NodeMatcher nm(node);
MachineRepresentation rep;
int value_input;
if (nm.IsStore()) {
rep = StoreRepresentationOf(node->op()).representation();
value_input = 2;
} else {
DCHECK(nm.IsUnalignedStore());
rep = UnalignedStoreRepresentationOf(node->op());
value_input = 2;
}
Node* const value = node->InputAt(value_input);
switch (value->opcode()) {
case IrOpcode::kWord32And: {
Uint32BinopMatcher m(value);
if (m.right().HasResolvedValue() &&
((rep == MachineRepresentation::kWord8 &&
(m.right().ResolvedValue() & 0xFF) == 0xFF) ||
(rep == MachineRepresentation::kWord16 &&
(m.right().ResolvedValue() & 0xFFFF) == 0xFFFF))) {
node->ReplaceInput(value_input, m.left().node());
return Changed(node);
}
break;
}
case IrOpcode::kWord32Sar: {
Int32BinopMatcher m(value);
if (m.left().IsWord32Shl() && ((rep == MachineRepresentation::kWord8 &&
m.right().IsInRange(1, 24)) ||
(rep == MachineRepresentation::kWord16 &&
m.right().IsInRange(1, 16)))) {
Int32BinopMatcher mleft(m.left().node());
if (mleft.right().Is(m.right().ResolvedValue())) {
node->ReplaceInput(value_input, mleft.left().node());
return Changed(node);
}
}
break;
}
default:
break;
}
return NoChange();
}
Reduction MachineOperatorReducer::ReduceProjection(size_t index, Node* node) {
switch (node->opcode()) {
case IrOpcode::kInt32AddWithOverflow: {
DCHECK(index == 0 || index == 1);
Int32BinopMatcher m(node);
if (m.IsFoldable()) {
int32_t val;
bool ovf = base::bits::SignedAddOverflow32(
m.left().ResolvedValue(), m.right().ResolvedValue(), &val);
return ReplaceInt32(index == 0 ? val : ovf);
}
if (m.right().Is(0)) {
return Replace(index == 0 ? m.left().node() : m.right().node());
}
break;
}
case IrOpcode::kInt32SubWithOverflow: {
DCHECK(index == 0 || index == 1);
Int32BinopMatcher m(node);
if (m.IsFoldable()) {
int32_t val;
bool ovf = base::bits::SignedSubOverflow32(
m.left().ResolvedValue(), m.right().ResolvedValue(), &val);
return ReplaceInt32(index == 0 ? val : ovf);
}
if (m.right().Is(0)) {
return Replace(index == 0 ? m.left().node() : m.right().node());
}
break;
}
case IrOpcode::kInt32MulWithOverflow: {
DCHECK(index == 0 || index == 1);
Int32BinopMatcher m(node);
if (m.IsFoldable()) {
int32_t val;
bool ovf = base::bits::SignedMulOverflow32(
m.left().ResolvedValue(), m.right().ResolvedValue(), &val);
return ReplaceInt32(index == 0 ? val : ovf);
}
if (m.right().Is(0)) {
return Replace(m.right().node());
}
if (m.right().Is(1)) {
return index == 0 ? Replace(m.left().node()) : ReplaceInt32(0);
}
break;
}
default:
break;
}
return NoChange();
}
Reduction MachineOperatorReducer::ReduceWord32Comparisons(Node* node) {
DCHECK(node->opcode() == IrOpcode::kInt32LessThan ||
node->opcode() == IrOpcode::kInt32LessThanOrEqual ||
node->opcode() == IrOpcode::kUint32LessThan ||
node->opcode() == IrOpcode::kUint32LessThanOrEqual);
Int32BinopMatcher m(node);
// (x >>> K) < (y >>> K) => x < y if only zeros shifted out
if (m.left().op() == machine()->Word32SarShiftOutZeros() &&
m.right().op() == machine()->Word32SarShiftOutZeros()) {
Int32BinopMatcher mleft(m.left().node());
Int32BinopMatcher mright(m.right().node());
if (mleft.right().HasResolvedValue() &&
mright.right().Is(mleft.right().ResolvedValue())) {
node->ReplaceInput(0, mleft.left().node());
node->ReplaceInput(1, mright.left().node());
return Changed(node);
}
}
return NoChange();
}
const Operator* MachineOperatorReducer::Map64To32Comparison(
const Operator* op, bool sign_extended) {
switch (op->opcode()) {
case IrOpcode::kInt64LessThan:
return sign_extended ? machine()->Int32LessThan()
: machine()->Uint32LessThan();
case IrOpcode::kInt64LessThanOrEqual:
return sign_extended ? machine()->Int32LessThanOrEqual()
: machine()->Uint32LessThanOrEqual();
case IrOpcode::kUint64LessThan:
return machine()->Uint32LessThan();
case IrOpcode::kUint64LessThanOrEqual:
return machine()->Uint32LessThanOrEqual();
default:
UNREACHABLE();
}
}
Reduction MachineOperatorReducer::ReduceWord64Comparisons(Node* node) {
DCHECK(node->opcode() == IrOpcode::kInt64LessThan ||
node->opcode() == IrOpcode::kInt64LessThanOrEqual ||
node->opcode() == IrOpcode::kUint64LessThan ||
node->opcode() == IrOpcode::kUint64LessThanOrEqual);
Int64BinopMatcher m(node);
bool sign_extended =
m.left().IsChangeInt32ToInt64() && m.right().IsChangeInt32ToInt64();
if (sign_extended || (m.left().IsChangeUint32ToUint64() &&
m.right().IsChangeUint32ToUint64())) {
node->ReplaceInput(0, NodeProperties::GetValueInput(m.left().node(), 0));
node->ReplaceInput(1, NodeProperties::GetValueInput(m.right().node(), 0));
NodeProperties::ChangeOp(node,
Map64To32Comparison(node->op(), sign_extended));
return Changed(node).FollowedBy(Reduce(node));
}
// (x >>> K) < (y >>> K) => x < y if only zeros shifted out
// This is useful for Smi untagging, which results in such a shift.
if (m.left().op() == machine()->Word64SarShiftOutZeros() &&
m.right().op() == machine()->Word64SarShiftOutZeros()) {
Int64BinopMatcher mleft(m.left().node());
Int64BinopMatcher mright(m.right().node());
if (mleft.right().HasResolvedValue() &&
mright.right().Is(mleft.right().ResolvedValue())) {
node->ReplaceInput(0, mleft.left().node());
node->ReplaceInput(1, mright.left().node());
return Changed(node);
}
}
return NoChange();
}
Reduction MachineOperatorReducer::ReduceWord32Shifts(Node* node) {
DCHECK((node->opcode() == IrOpcode::kWord32Shl) ||
(node->opcode() == IrOpcode::kWord32Shr) ||
(node->opcode() == IrOpcode::kWord32Sar));
if (machine()->Word32ShiftIsSafe()) {
// Remove the explicit 'and' with 0x1F if the shift provided by the machine
// instruction matches that required by JavaScript.
Int32BinopMatcher m(node);
if (m.right().IsWord32And()) {
Int32BinopMatcher mright(m.right().node());
if (mright.right().Is(0x1F)) {
node->ReplaceInput(1, mright.left().node());
return Changed(node);
}
}
}
return NoChange();
}
Reduction MachineOperatorReducer::ReduceWord32Shl(Node* node) {
DCHECK_EQ(IrOpcode::kWord32Shl, node->opcode());
Int32BinopMatcher m(node);
if (m.right().Is(0)) return Replace(m.left().node()); // x << 0 => x
if (m.IsFoldable()) { // K << K => K (K stands for arbitrary constants)
return ReplaceInt32(base::ShlWithWraparound(m.left().ResolvedValue(),
m.right().ResolvedValue()));
}
if (m.right().IsInRange(1, 31)) {
if (m.left().IsWord32Sar() || m.left().IsWord32Shr()) {
Int32BinopMatcher mleft(m.left().node());
// If x >> K only shifted out zeros:
// (x >> K) << L => x if K == L
// (x >> K) << L => x >> (K-L) if K > L
// (x >> K) << L => x << (L-K) if K < L
// Since this is used for Smi untagging, we currently only need it for
// signed shifts.
if (mleft.op() == machine()->Word32SarShiftOutZeros() &&
mleft.right().IsInRange(1, 31)) {
Node* x = mleft.left().node();
int k = mleft.right().ResolvedValue();
int l = m.right().ResolvedValue();
if (k == l) {
return Replace(x);
} else if (k > l) {
node->ReplaceInput(0, x);
node->ReplaceInput(1, Uint32Constant(k - l));
NodeProperties::ChangeOp(node, machine()->Word32Sar());
return Changed(node).FollowedBy(ReduceWord32Sar(node));
} else {
DCHECK(k < l);
node->ReplaceInput(0, x);
node->ReplaceInput(1, Uint32Constant(l - k));
return Changed(node);
}
}
// (x >>> K) << K => x & ~(2^K - 1)
// (x >> K) << K => x & ~(2^K - 1)
if (mleft.right().Is(m.right().ResolvedValue())) {
node->ReplaceInput(0, mleft.left().node());
node->ReplaceInput(1,
Uint32Constant(std::numeric_limits<uint32_t>::max()
<< m.right().ResolvedValue()));
NodeProperties::ChangeOp(node, machine()->Word32And());
return Changed(node).FollowedBy(ReduceWord32And(node));
}
}
}
return ReduceWord32Shifts(node);
}
Reduction MachineOperatorReducer::ReduceWord64Shl(Node* node) {
DCHECK_EQ(IrOpcode::kWord64Shl, node->opcode());
Int64BinopMatcher m(node);
if (m.right().Is(0)) return Replace(m.left().node()); // x << 0 => x
if (m.IsFoldable()) { // K << K => K (K stands for arbitrary constants)
return ReplaceInt64(base::ShlWithWraparound(m.left().ResolvedValue(),
m.right().ResolvedValue()));
}
if (m.right().IsInRange(1, 63) &&
(m.left().IsWord64Sar() || m.left().IsWord64Shr())) {
Int64BinopMatcher mleft(m.left().node());
// If x >> K only shifted out zeros:
// (x >> K) << L => x if K == L
// (x >> K) << L => x >> (K-L) if K > L
// (x >> K) << L => x << (L-K) if K < L
// Since this is used for Smi untagging, we currently only need it for
// signed shifts.
if (mleft.op() == machine()->Word64SarShiftOutZeros() &&
mleft.right().IsInRange(1, 63)) {
Node* x = mleft.left().node();
int64_t k = mleft.right().ResolvedValue();
int64_t l = m.right().ResolvedValue();
if (k == l) {
return Replace(x);
} else if (k > l) {
node->ReplaceInput(0, x);
node->ReplaceInput(1, Uint64Constant(k - l));
NodeProperties::ChangeOp(node, machine()->Word64Sar());
return Changed(node).FollowedBy(ReduceWord64Sar(node));
} else {
DCHECK(k < l);
node->ReplaceInput(0, x);
node->ReplaceInput(1, Uint64Constant(l - k));
return Changed(node);
}
}
// (x >>> K) << K => x & ~(2^K - 1)
// (x >> K) << K => x & ~(2^K - 1)
if (mleft.right().Is(m.right().ResolvedValue())) {
node->ReplaceInput(0, mleft.left().node());
node->ReplaceInput(1, Uint64Constant(std::numeric_limits<uint64_t>::max()
<< m.right().ResolvedValue()));
NodeProperties::ChangeOp(node, machine()->Word64And());
return Changed(node).FollowedBy(ReduceWord64And(node));
}
}
return NoChange();
}
Reduction MachineOperatorReducer::ReduceWord32Shr(Node* node) {
Uint32BinopMatcher m(node);
if (m.right().Is(0)) return Replace(m.left().node()); // x >>> 0 => x
if (m.IsFoldable()) { // K >>> K => K (K stands for arbitrary constants)
return ReplaceInt32(m.left().ResolvedValue() >>
(m.right().ResolvedValue() & 31));
}
if (m.left().IsWord32And() && m.right().HasResolvedValue()) {
Uint32BinopMatcher mleft(m.left().node());
if (mleft.right().HasResolvedValue()) {
uint32_t shift = m.right().ResolvedValue() & 31;
uint32_t mask = mleft.right().ResolvedValue();
if ((mask >> shift) == 0) {
// (m >>> s) == 0 implies ((x & m) >>> s) == 0
return ReplaceInt32(0);
}
}
}
return ReduceWord32Shifts(node);
}
Reduction MachineOperatorReducer::ReduceWord64Shr(Node* node) {
DCHECK_EQ(IrOpcode::kWord64Shr, node->opcode());
Uint64BinopMatcher m(node);
if (m.right().Is(0)) return Replace(m.left().node()); // x >>> 0 => x
if (m.IsFoldable()) { // K >> K => K (K stands for arbitrary constants)
return ReplaceInt64(m.left().ResolvedValue() >>
(m.right().ResolvedValue() & 63));
}
return NoChange();
}
Reduction MachineOperatorReducer::ReduceWord32Sar(Node* node) {
Int32BinopMatcher m(node);
if (m.right().Is(0)) return Replace(m.left().node()); // x >> 0 => x
if (m.IsFoldable()) { // K >> K => K (K stands for arbitrary constants)
return ReplaceInt32(m.left().ResolvedValue() >>
(m.right().ResolvedValue() & 31));
}
if (m.left().IsWord32Shl()) {
Int32BinopMatcher mleft(m.left().node());
if (mleft.left().IsComparison()) {
if (m.right().Is(31) && mleft.right().Is(31)) {
// Comparison << 31 >> 31 => 0 - Comparison
node->ReplaceInput(0, Int32Constant(0));
node->ReplaceInput(1, mleft.left().node());
NodeProperties::ChangeOp(node, machine()->Int32Sub());
return Changed(node).FollowedBy(ReduceInt32Sub(node));
}
} else if (mleft.left().IsLoad()) {
LoadRepresentation const rep =
LoadRepresentationOf(mleft.left().node()->op());
if (m.right().Is(24) && mleft.right().Is(24) &&
rep == MachineType::Int8()) {
// Load[kMachInt8] << 24 >> 24 => Load[kMachInt8]
return Replace(mleft.left().node());
}
if (m.right().Is(16) && mleft.right().Is(16) &&
rep == MachineType::Int16()) {
// Load[kMachInt16] << 16 >> 16 => Load[kMachInt8]
return Replace(mleft.left().node());
}
}
}
return ReduceWord32Shifts(node);
}
Reduction MachineOperatorReducer::ReduceWord64Sar(Node* node) {
Int64BinopMatcher m(node);
if (m.right().Is(0)) return Replace(m.left().node()); // x >> 0 => x
if (m.IsFoldable()) {
return ReplaceInt64(m.left().ResolvedValue() >>
(m.right().ResolvedValue() & 63));
}
return NoChange();
}
template <typename WordNAdapter>
Reduction MachineOperatorReducer::ReduceWordNAnd(Node* node) {
using A = WordNAdapter;
A a(this);
typename A::IntNBinopMatcher m(node);
if (m.right().Is(0)) return Replace(m.right().node()); // x & 0 => 0
if (m.right().Is(-1)) return Replace(m.left().node()); // x & -1 => x
if (m.left().IsComparison() && m.right().Is(1)) { // CMP & 1 => CMP
return Replace(m.left().node());
}
if (m.IsFoldable()) { // K & K => K (K stands for arbitrary constants)
return a.ReplaceIntN(m.left().ResolvedValue() & m.right().ResolvedValue());
}
if (m.LeftEqualsRight()) return Replace(m.left().node()); // x & x => x
if (A::IsWordNAnd(m.left()) && m.right().HasResolvedValue()) {
typename A::IntNBinopMatcher mleft(m.left().node());
if (mleft.right().HasResolvedValue()) { // (x & K) & K => x & K
node->ReplaceInput(0, mleft.left().node());
node->ReplaceInput(1, a.IntNConstant(m.right().ResolvedValue() &
mleft.right().ResolvedValue()));
return Changed(node).FollowedBy(a.ReduceWordNAnd(node));
}
}
if (m.right().IsNegativePowerOf2()) {
typename A::intN_t const mask = m.right().ResolvedValue();
typename A::intN_t const neg_mask = base::NegateWithWraparound(mask);
if (A::IsWordNShl(m.left())) {
typename A::UintNBinopMatcher mleft(m.left().node());
if (mleft.right().HasResolvedValue() &&
(mleft.right().ResolvedValue() & (A::WORD_SIZE - 1)) >=
base::bits::CountTrailingZeros(mask)) {
// (x << L) & (-1 << K) => x << L iff L >= K
return Replace(mleft.node());
}
} else if (A::IsIntNAdd(m.left())) {
typename A::IntNBinopMatcher mleft(m.left().node());
if (mleft.right().HasResolvedValue() &&
(mleft.right().ResolvedValue() & mask) ==
mleft.right().ResolvedValue()) {
// (x + (K << L)) & (-1 << L) => (x & (-1 << L)) + (K << L)
node->ReplaceInput(0,
a.WordNAnd(mleft.left().node(), m.right().node()));
node->ReplaceInput(1, mleft.right().node());
NodeProperties::ChangeOp(node, a.IntNAdd(machine()));
return Changed(node).FollowedBy(a.ReduceIntNAdd(node));
}
if (A::IsIntNMul(mleft.left())) {
typename A::IntNBinopMatcher mleftleft(mleft.left().node());
if (mleftleft.right().IsMultipleOf(neg_mask)) {
// (y * (K << L) + x) & (-1 << L) => (x & (-1 << L)) + y * (K << L)
node->ReplaceInput(
0, a.WordNAnd(mleft.right().node(), m.right().node()));
node->ReplaceInput(1, mleftleft.node());
NodeProperties::ChangeOp(node, a.IntNAdd(machine()));
return Changed(node).FollowedBy(a.ReduceIntNAdd(node));
}
}
if (A::IsIntNMul(mleft.right())) {
typename A::IntNBinopMatcher mleftright(mleft.right().node());
if (mleftright.right().IsMultipleOf(neg_mask)) {
// (x + y * (K << L)) & (-1 << L) => (x & (-1 << L)) + y * (K << L)
node->ReplaceInput(0,
a.WordNAnd(mleft.left().node(), m.right().node()));
node->ReplaceInput(1, mleftright.node());
NodeProperties::ChangeOp(node, a.IntNAdd(machine()));
return Changed(node).FollowedBy(a.ReduceIntNAdd(node));
}
}
if (A::IsWordNShl(mleft.left())) {
typename A::IntNBinopMatcher mleftleft(mleft.left().node());
if (mleftleft.right().Is(base::bits::CountTrailingZeros(mask))) {
// (y << L + x) & (-1 << L) => (x & (-1 << L)) + y << L
node->ReplaceInput(
0, a.WordNAnd(mleft.right().node(), m.right().node()));
node->ReplaceInput(1, mleftleft.node());
NodeProperties::ChangeOp(node, a.IntNAdd(machine()));
return Changed(node).FollowedBy(a.ReduceIntNAdd(node));
}
}
if (A::IsWordNShl(mleft.right())) {
typename A::IntNBinopMatcher mleftright(mleft.right().node());
if (mleftright.right().Is(base::bits::CountTrailingZeros(mask))) {
// (x + y << L) & (-1 << L) => (x & (-1 << L)) + y << L
node->ReplaceInput(0,
a.WordNAnd(mleft.left().node(), m.right().node()));
node->ReplaceInput(1, mleftright.node());
NodeProperties::ChangeOp(node, a.IntNAdd(machine()));
return Changed(node).FollowedBy(a.ReduceIntNAdd(node));
}
}
} else if (A::IsIntNMul(m.left())) {
typename A::IntNBinopMatcher mleft(m.left().node());
if (mleft.right().IsMultipleOf(neg_mask)) {
// (x * (K << L)) & (-1 << L) => x * (K << L)
return Replace(mleft.node());
}
}
}
return NoChange();
}
namespace {
// Represents an operation of the form `(source & mask) == masked_value`.
// where each bit set in masked_value also has to be set in mask.
struct BitfieldCheck {
Node* const source;
uint32_t const mask;
uint32_t const masked_value;
bool const truncate_from_64_bit;
BitfieldCheck(Node* source, uint32_t mask, uint32_t masked_value,
bool truncate_from_64_bit)
: source(source),
mask(mask),
masked_value(masked_value),
truncate_from_64_bit(truncate_from_64_bit) {
CHECK_EQ(masked_value & ~mask, 0);
}
static base::Optional<BitfieldCheck> Detect(Node* node) {
// There are two patterns to check for here:
// 1. Single-bit checks: `(val >> shift) & 1`, where:
// - the shift may be omitted, and/or
// - the result may be truncated from 64 to 32
// 2. Equality checks: `(val & mask) == expected`, where:
// - val may be truncated from 64 to 32 before masking (see
// ReduceWord32EqualForConstantRhs)
if (node->opcode() == IrOpcode::kWord32Equal) {
Uint32BinopMatcher eq(node);
if (eq.left().IsWord32And()) {
Uint32BinopMatcher mand(eq.left().node());
if (mand.right().HasResolvedValue() && eq.right().HasResolvedValue()) {
uint32_t mask = mand.right().ResolvedValue();
uint32_t masked_value = eq.right().ResolvedValue();
if ((masked_value & ~mask) != 0) return {};
if (mand.left().IsTruncateInt64ToInt32()) {
return BitfieldCheck(
NodeProperties::GetValueInput(mand.left().node(), 0), mask,
masked_value, true);
} else {
return BitfieldCheck(mand.left().node(), mask, masked_value, false);
}
}
}
} else {
if (node->opcode() == IrOpcode::kTruncateInt64ToInt32) {
return TryDetectShiftAndMaskOneBit<Word64Adapter>(
NodeProperties::GetValueInput(node, 0));
} else {
return TryDetectShiftAndMaskOneBit<Word32Adapter>(node);
}
}
return {};
}
base::Optional<BitfieldCheck> TryCombine(const BitfieldCheck& other) {
if (source != other.source ||
truncate_from_64_bit != other.truncate_from_64_bit)
return {};
uint32_t overlapping_bits = mask & other.mask;
// It would be kind of strange to have any overlapping bits, but they can be
// allowed as long as they don't require opposite values in the same
// positions.
if ((masked_value & overlapping_bits) !=
(other.masked_value & overlapping_bits))
return {};
return BitfieldCheck{source, mask | other.mask,
masked_value | other.masked_value,
truncate_from_64_bit};
}
private:
template <typename WordNAdapter>
static base::Optional<BitfieldCheck> TryDetectShiftAndMaskOneBit(Node* node) {
// Look for the pattern `(val >> shift) & 1`. The shift may be omitted.
if (WordNAdapter::IsWordNAnd(NodeMatcher(node))) {
typename WordNAdapter::IntNBinopMatcher mand(node);
if (mand.right().HasResolvedValue() &&
mand.right().ResolvedValue() == 1) {
if (WordNAdapter::IsWordNShr(mand.left()) ||
WordNAdapter::IsWordNSar(mand.left())) {
typename WordNAdapter::UintNBinopMatcher shift(mand.left().node());
if (shift.right().HasResolvedValue() &&
shift.right().ResolvedValue() < 32u) {
uint32_t mask = 1 << shift.right().ResolvedValue();
return BitfieldCheck{shift.left().node(), mask, mask,
WordNAdapter::WORD_SIZE == 64};
}
}
return BitfieldCheck{mand.left().node(), 1, 1,
WordNAdapter::WORD_SIZE == 64};
}
}
return {};
}
};
} // namespace
Reduction MachineOperatorReducer::ReduceWord32And(Node* node) {
DCHECK_EQ(IrOpcode::kWord32And, node->opcode());
Reduction reduction = ReduceWordNAnd<Word32Adapter>(node);
if (reduction.Changed()) {
return reduction;
}
// Attempt to detect multiple bitfield checks from the same bitfield struct
// and fold them into a single check.
Int32BinopMatcher m(node);
if (auto right_bitfield = BitfieldCheck::Detect(m.right().node())) {
if (auto left_bitfield = BitfieldCheck::Detect(m.left().node())) {
if (auto combined_bitfield = left_bitfield->TryCombine(*right_bitfield)) {
Node* source = combined_bitfield->source;
if (combined_bitfield->truncate_from_64_bit) {
source = TruncateInt64ToInt32(source);
}
node->ReplaceInput(0, Word32And(source, combined_bitfield->mask));
node->ReplaceInput(1, Int32Constant(combined_bitfield->masked_value));
NodeProperties::ChangeOp(node, machine()->Word32Equal());
return Changed(node).FollowedBy(ReduceWord32Equal(node));
}
}
}
return NoChange();
}
Reduction MachineOperatorReducer::ReduceWord64And(Node* node) {
DCHECK_EQ(IrOpcode::kWord64And, node->opcode());
return ReduceWordNAnd<Word64Adapter>(node);
}
Reduction MachineOperatorReducer::TryMatchWord32Ror(Node* node) {
// Recognize rotation, we are matching and transforming as follows:
// x << y | x >>> (32 - y) => x ror (32 - y)
// x << (32 - y) | x >>> y => x ror y
// x << y ^ x >>> (32 - y) => x ror (32 - y) if y & 31 != 0
// x << (32 - y) ^ x >>> y => x ror y if y & 31 != 0
// (As well as the commuted forms.)
// Note the side condition for XOR: the optimization doesn't hold for
// multiples of 32.
DCHECK(IrOpcode::kWord32Or == node->opcode() ||
IrOpcode::kWord32Xor == node->opcode());
Int32BinopMatcher m(node);
Node* shl = nullptr;
Node* shr = nullptr;
if (m.left().IsWord32Shl() && m.right().IsWord32Shr()) {
shl = m.left().node();
shr = m.right().node();
} else if (m.left().IsWord32Shr() && m.right().IsWord32Shl()) {
shl = m.right().node();
shr = m.left().node();
} else {
return NoChange();
}
Int32BinopMatcher mshl(shl);
Int32BinopMatcher mshr(shr);
if (mshl.left().node() != mshr.left().node()) return NoChange();
if (mshl.right().HasResolvedValue() && mshr.right().HasResolvedValue()) {
// Case where y is a constant.
if (mshl.right().ResolvedValue() + mshr.right().ResolvedValue() != 32) {
return NoChange();
}
if (node->opcode() == IrOpcode::kWord32Xor &&
(mshl.right().ResolvedValue() & 31) == 0) {
return NoChange();
}
} else {
Node* sub = nullptr;
Node* y = nullptr;
if (mshl.right().IsInt32Sub()) {
sub = mshl.right().node();
y = mshr.right().node();
} else if (mshr.right().IsInt32Sub()) {
sub = mshr.right().node();
y = mshl.right().node();
} else {
return NoChange();
}
Int32BinopMatcher msub(sub);
if (!msub.left().Is(32) || msub.right().node() != y) return NoChange();
if (node->opcode() == IrOpcode::kWord32Xor) {
return NoChange(); // Can't guarantee y & 31 != 0.
}
}
node->ReplaceInput(0, mshl.left().node());
node->ReplaceInput(1, mshr.right().node());
NodeProperties::ChangeOp(node, machine()->Word32Ror());
return Changed(node);
}
template <typename WordNAdapter>
Reduction MachineOperatorReducer::ReduceWordNOr(Node* node) {
using A = WordNAdapter;
A a(this);
typename A::IntNBinopMatcher m(node);
if (m.right().Is(0)) return Replace(m.left().node()); // x | 0 => x
if (m.right().Is(-1)) return Replace(m.right().node()); // x | -1 => -1
if (m.IsFoldable()) { // K | K => K (K stands for arbitrary constants)
return a.ReplaceIntN(m.left().ResolvedValue() | m.right().ResolvedValue());
}
if (m.LeftEqualsRight()) return Replace(m.left().node()); // x | x => x
// (x & K1) | K2 => x | K2 if K2 has ones for every zero bit in K1.
// This case can be constructed by UpdateWord and UpdateWord32 in CSA.
if (m.right().HasResolvedValue()) {
if (A::IsWordNAnd(m.left())) {
typename A::IntNBinopMatcher mand(m.left().node());
if (mand.right().HasResolvedValue()) {
if ((m.right().ResolvedValue() | mand.right().ResolvedValue()) == -1) {
node->ReplaceInput(0, mand.left().node());
return Changed(node);
}
}
}
}
return a.TryMatchWordNRor(node);
}
Reduction MachineOperatorReducer::ReduceWord32Or(Node* node) {
DCHECK_EQ(IrOpcode::kWord32Or, node->opcode());
return ReduceWordNOr<Word32Adapter>(node);
}
Reduction MachineOperatorReducer::ReduceWord64Or(Node* node) {
DCHECK_EQ(IrOpcode::kWord64Or, node->opcode());
return ReduceWordNOr<Word64Adapter>(node);
}
template <typename WordNAdapter>
Reduction MachineOperatorReducer::ReduceWordNXor(Node* node) {
using A = WordNAdapter;
A a(this);
typename A::IntNBinopMatcher m(node);
if (m.right().Is(0)) return Replace(m.left().node()); // x ^ 0 => x
if (m.IsFoldable()) { // K ^ K => K (K stands for arbitrary constants)
return a.ReplaceIntN(m.left().ResolvedValue() ^ m.right().ResolvedValue());
}
if (m.LeftEqualsRight()) return ReplaceInt32(0); // x ^ x => 0
if (A::IsWordNXor(m.left()) && m.right().Is(-1)) {
typename A::IntNBinopMatcher mleft(m.left().node());
if (mleft.right().Is(-1)) { // (x ^ -1) ^ -1 => x
return Replace(mleft.left().node());
}
}
return a.TryMatchWordNRor(node);
}
Reduction MachineOperatorReducer::ReduceWord32Xor(Node* node) {
DCHECK_EQ(IrOpcode::kWord32Xor, node->opcode());
Int32BinopMatcher m(node);
if (m.right().IsWord32Equal() && m.left().Is(1)) {
return Replace(Word32Equal(m.right().node(), Int32Constant(0)));
}
return ReduceWordNXor<Word32Adapter>(node);
}
Reduction MachineOperatorReducer::ReduceWord64Xor(Node* node) {
DCHECK_EQ(IrOpcode::kWord64Xor, node->opcode());
return ReduceWordNXor<Word64Adapter>(node);
}
Reduction MachineOperatorReducer::ReduceWord32Equal(Node* node) {
Int32BinopMatcher m(node);
if (m.IsFoldable()) { // K == K => K (K stands for arbitrary constants)
return ReplaceBool(m.left().ResolvedValue() == m.right().ResolvedValue());
}
if (m.left().IsInt32Sub() && m.right().Is(0)) { // x - y == 0 => x == y
Int32BinopMatcher msub(m.left().node());
node->ReplaceInput(0, msub.left().node());
node->ReplaceInput(1, msub.right().node());
return Changed(node);
}
// TODO(turbofan): fold HeapConstant, ExternalReference, pointer compares
if (m.LeftEqualsRight()) return ReplaceBool(true); // x == x => true
if (m.right().HasResolvedValue()) {
base::Optional<std::pair<Node*, uint32_t>> replacements;
if (m.left().IsTruncateInt64ToInt32()) {
replacements = ReduceWord32EqualForConstantRhs<Word64Adapter>(
NodeProperties::GetValueInput(m.left().node(), 0),
static_cast<uint32_t>(m.right().ResolvedValue()));
} else {
replacements = ReduceWord32EqualForConstantRhs<Word32Adapter>(
m.left().node(), static_cast<uint32_t>(m.right().ResolvedValue()));
}
if (replacements) {
node->ReplaceInput(0, replacements->first);
node->ReplaceInput(1, Uint32Constant(replacements->second));
return Changed(node);
}
}
// This is a workaround for not having escape analysis for wasm
// (machine-level) turbofan graphs.
if (!ObjectsMayAlias(m.left().node(), m.right().node())) {
return ReplaceBool(false);
}
return NoChange();
}
Reduction MachineOperatorReducer::ReduceFloat64InsertLowWord32(Node* node) {
DCHECK_EQ(IrOpcode::kFloat64InsertLowWord32, node->opcode());
Float64Matcher mlhs(node->InputAt(0));
Uint32Matcher mrhs(node->InputAt(1));
if (mlhs.HasResolvedValue() && mrhs.HasResolvedValue()) {
return ReplaceFloat64(
bit_cast<double>((bit_cast<uint64_t>(mlhs.ResolvedValue()) &
uint64_t{0xFFFFFFFF00000000}) |
mrhs.ResolvedValue()));
}
return NoChange();
}
Reduction MachineOperatorReducer::ReduceFloat64InsertHighWord32(Node* node) {
DCHECK_EQ(IrOpcode::kFloat64InsertHighWord32, node->opcode());
Float64Matcher mlhs(node->InputAt(0));
Uint32Matcher mrhs(node->InputAt(1));
if (mlhs.HasResolvedValue() && mrhs.HasResolvedValue()) {
return ReplaceFloat64(bit_cast<double>(
(bit_cast<uint64_t>(mlhs.ResolvedValue()) & uint64_t{0xFFFFFFFF}) |
(static_cast<uint64_t>(mrhs.ResolvedValue()) << 32)));
}
return NoChange();
}
namespace {
bool IsFloat64RepresentableAsFloat32(const Float64Matcher& m) {
if (m.HasResolvedValue()) {
double v = m.ResolvedValue();
return DoubleToFloat32(v) == v;
}
return false;
}
} // namespace
Reduction MachineOperatorReducer::ReduceFloat64Compare(Node* node) {
DCHECK(IrOpcode::kFloat64Equal == node->opcode() ||
IrOpcode::kFloat64LessThan == node->opcode() ||
IrOpcode::kFloat64LessThanOrEqual == node->opcode());
Float64BinopMatcher m(node);
if (m.IsFoldable()) {
switch (node->opcode()) {
case IrOpcode::kFloat64Equal:
return ReplaceBool(m.left().ResolvedValue() ==
m.right().ResolvedValue());
case IrOpcode::kFloat64LessThan:
return ReplaceBool(m.left().ResolvedValue() <
m.right().ResolvedValue());
case IrOpcode::kFloat64LessThanOrEqual:
return ReplaceBool(m.left().ResolvedValue() <=
m.right().ResolvedValue());
default:
UNREACHABLE();
}
} else if ((m.left().IsChangeFloat32ToFloat64() &&
m.right().IsChangeFloat32ToFloat64()) ||
(m.left().IsChangeFloat32ToFloat64() &&
IsFloat64RepresentableAsFloat32(m.right())) ||
(IsFloat64RepresentableAsFloat32(m.left()) &&
m.right().IsChangeFloat32ToFloat64())) {
// As all Float32 values have an exact representation in Float64, comparing
// two Float64 values both converted from Float32 is equivalent to comparing
// the original Float32s, so we can ignore the conversions. We can also
// reduce comparisons of converted Float64 values against constants that
// can be represented exactly as Float32.
switch (node->opcode()) {
case IrOpcode::kFloat64Equal:
NodeProperties::ChangeOp(node, machine()->Float32Equal());
break;
case IrOpcode::kFloat64LessThan:
NodeProperties::ChangeOp(node, machine()->Float32LessThan());
break;
case IrOpcode::kFloat64LessThanOrEqual:
NodeProperties::ChangeOp(node, machine()->Float32LessThanOrEqual());
break;
default:
UNREACHABLE();
}
node->ReplaceInput(
0, m.left().HasResolvedValue()
? Float32Constant(static_cast<float>(m.left().ResolvedValue()))
: m.left().InputAt(0));
node->ReplaceInput(
1, m.right().HasResolvedValue()
? Float32Constant(static_cast<float>(m.right().ResolvedValue()))
: m.right().InputAt(0));
return Changed(node);
}
return NoChange();
}
Reduction MachineOperatorReducer::ReduceFloat64RoundDown(Node* node) {
DCHECK_EQ(IrOpcode::kFloat64RoundDown, node->opcode());
Float64Matcher m(node->InputAt(0));
if (m.HasResolvedValue()) {
return ReplaceFloat64(std::floor(m.ResolvedValue()));
}
return NoChange();
}
Reduction MachineOperatorReducer::ReduceConditional(Node* node) {
DCHECK(node->opcode() == IrOpcode::kBranch ||
node->opcode() == IrOpcode::kDeoptimizeIf ||
node->opcode() == IrOpcode::kDeoptimizeUnless ||
node->opcode() == IrOpcode::kTrapIf ||
node->opcode() == IrOpcode::kTrapUnless);
// This reducer only applies operator reductions to the branch condition.
// Reductions involving control flow happen elsewhere. Non-zero inputs are
// considered true in all conditional ops.
NodeMatcher condition(NodeProperties::GetValueInput(node, 0));
if (condition.IsTruncateInt64ToInt32()) {
if (auto replacement =
ReduceConditionalN<Word64Adapter>(condition.node())) {
NodeProperties::ReplaceValueInput(node, *replacement, 0);
return Changed(node);
}
} else if (auto replacement = ReduceConditionalN<Word32Adapter>(node)) {
NodeProperties::ReplaceValueInput(node, *replacement, 0);
return Changed(node);
}
return NoChange();
}
template <typename WordNAdapter>
base::Optional<Node*> MachineOperatorReducer::ReduceConditionalN(Node* node) {
NodeMatcher condition(NodeProperties::GetValueInput(node, 0));
// Branch conditions are 32-bit comparisons against zero, so they are the
// opposite of a 32-bit `x == 0` node. To avoid repetition, we can reuse logic
// for Word32Equal: if `x == 0` can reduce to `y == 0`, then branch(x) can
// reduce to branch(y).
auto replacements =
ReduceWord32EqualForConstantRhs<WordNAdapter>(condition.node(), 0);
if (replacements && replacements->second == 0) return replacements->first;
return {};
}
template <typename WordNAdapter>
base::Optional<std::pair<Node*, uint32_t>>
MachineOperatorReducer::ReduceWord32EqualForConstantRhs(Node* lhs,
uint32_t rhs) {
if (WordNAdapter::IsWordNAnd(NodeMatcher(lhs))) {
typename WordNAdapter::UintNBinopMatcher mand(lhs);
if ((WordNAdapter::IsWordNShr(mand.left()) ||
WordNAdapter::IsWordNSar(mand.left())) &&
mand.right().HasResolvedValue()) {
typename WordNAdapter::UintNBinopMatcher mshift(mand.left().node());
// ((x >> K1) & K2) == K3 => (x & (K2 << K1)) == (K3 << K1)
if (mshift.right().HasResolvedValue()) {
auto shift_bits = mshift.right().ResolvedValue();
auto mask = mand.right().ResolvedValue();
// Make sure that we won't shift data off the end, and that all of the
// data ends up in the lower 32 bits for 64-bit mode.
if (shift_bits <= base::bits::CountLeadingZeros(mask) &&
shift_bits <= base::bits::CountLeadingZeros(rhs) &&
mask << shift_bits <= std::numeric_limits<uint32_t>::max()) {
Node* new_input = mshift.left().node();
uint32_t new_mask = static_cast<uint32_t>(mask << shift_bits);
uint32_t new_rhs = rhs << shift_bits;
if (WordNAdapter::WORD_SIZE == 64) {
// We can truncate before performing the And.
new_input = TruncateInt64ToInt32(new_input);
}
return std::make_pair(Word32And(new_input, new_mask), new_rhs);
}
}
}
}
return {};
}
CommonOperatorBuilder* MachineOperatorReducer::common() const {
return mcgraph()->common();
}
MachineOperatorBuilder* MachineOperatorReducer::machine() const {
return mcgraph()->machine();
}
Graph* MachineOperatorReducer::graph() const { return mcgraph()->graph(); }
} // namespace compiler
} // namespace internal
} // namespace v8
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