// 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 "src/base/bits.h" #include "src/base/division-by-constant.h" #include "src/base/ieee754.h" #include "src/codegen.h" #include "src/compiler/diamond.h" #include "src/compiler/graph.h" #include "src/compiler/js-graph.h" #include "src/compiler/node-matchers.h" #include "src/objects-inl.h" namespace v8 { namespace internal { namespace compiler { MachineOperatorReducer::MachineOperatorReducer(JSGraph* jsgraph, bool allow_signalling_nan) : jsgraph_(jsgraph), allow_signalling_nan_(allow_signalling_nan) {} MachineOperatorReducer::~MachineOperatorReducer() {} Node* MachineOperatorReducer::Float32Constant(volatile float value) { return graph()->NewNode(common()->Float32Constant(value)); } Node* MachineOperatorReducer::Float64Constant(volatile double value) { return jsgraph()->Float64Constant(value); } Node* MachineOperatorReducer::Int32Constant(int32_t value) { return jsgraph()->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::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::CountTrailingZeros32(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; } // 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::kWord32Or: return ReduceWord32Or(node); case IrOpcode::kWord32Xor: return ReduceWord32Xor(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 return ReplaceInt32( base::bits::RotateRight32(m.left().Value(), m.right().Value())); } break; } case IrOpcode::kWord32Equal: { Int32BinopMatcher m(node); if (m.IsFoldable()) { // K == K => K return ReplaceBool(m.left().Value() == m.right().Value()); } 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 break; } case IrOpcode::kWord64Equal: { Int64BinopMatcher m(node); if (m.IsFoldable()) { // K == K => K return ReplaceBool(m.left().Value() == m.right().Value()); } 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 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 return ReplaceInt32(m.left().Value() * m.right().Value()); } 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(WhichPowerOf2(m.right().Value()))); NodeProperties::ChangeOp(node, machine()->Word32Shl()); Reduction reduction = ReduceWord32Shl(node); return reduction.Changed() ? reduction : 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::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 return ReplaceBool(m.left().Value() < m.right().Value()); } 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); } } break; } case IrOpcode::kInt32LessThanOrEqual: { Int32BinopMatcher m(node); if (m.IsFoldable()) { // K <= K => K return ReplaceBool(m.left().Value() <= m.right().Value()); } if (m.LeftEqualsRight()) return ReplaceBool(true); // x <= x => true break; } 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 return ReplaceBool(m.left().Value() < m.right().Value()); } if (m.LeftEqualsRight()) return ReplaceBool(false); // x < x => false if (m.left().IsWord32Sar() && m.right().HasValue()) { Int32BinopMatcher mleft(m.left().node()); if (mleft.right().HasValue()) { // (x >> K) < C => x < (C << K) // when C < (M >> K) const uint32_t c = m.right().Value(); const uint32_t k = mleft.right().Value() & 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. } } break; } 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 return ReplaceBool(m.left().Value() <= m.right().Value()); } if (m.LeftEqualsRight()) return ReplaceBool(true); // x <= x => true break; } case IrOpcode::kFloat32Sub: { Float32BinopMatcher m(node); if (allow_signalling_nan_ && m.right().Is(0) && (copysign(1.0, m.right().Value()) > 0)) { return Replace(m.left().node()); // x - 0 => x } if (m.right().IsNaN()) { // x - NaN => NaN // Do some calculation to make a signalling NaN quiet. return ReplaceFloat32(m.right().Value() - m.right().Value()); } if (m.left().IsNaN()) { // NaN - x => NaN // Do some calculation to make a signalling NaN quiet. return ReplaceFloat32(m.left().Value() - m.left().Value()); } if (m.IsFoldable()) { // L - R => (L - R) return ReplaceFloat32(m.left().Value() - m.right().Value()); } 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 // Do some calculation to make a signalling NaN quiet. return ReplaceFloat64(m.right().Value() - m.right().Value()); } if (m.IsFoldable()) { // K + K => K return ReplaceFloat64(m.left().Value() + m.right().Value()); } break; } case IrOpcode::kFloat64Sub: { Float64BinopMatcher m(node); if (allow_signalling_nan_ && m.right().Is(0) && (Double(m.right().Value()).Sign() > 0)) { return Replace(m.left().node()); // x - 0 => x } if (m.right().IsNaN()) { // x - NaN => NaN // Do some calculation to make a signalling NaN quiet. return ReplaceFloat64(m.right().Value() - m.right().Value()); } if (m.left().IsNaN()) { // NaN - x => NaN // Do some calculation to make a signalling NaN quiet. return ReplaceFloat64(m.left().Value() - m.left().Value()); } if (m.IsFoldable()) { // L - R => (L - R) return ReplaceFloat64(m.left().Value() - m.right().Value()); } 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 // Do some calculation to make a signalling NaN quiet. return ReplaceFloat64(m.right().Value() - m.right().Value()); } if (m.IsFoldable()) { // K * K => K return ReplaceFloat64(m.left().Value() * m.right().Value()); } 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 // Do some calculation to make a signalling NaN quiet. return ReplaceFloat64(m.right().Value() - m.right().Value()); } if (m.left().IsNaN()) { // NaN / x => NaN // Do some calculation to make a signalling NaN quiet. return ReplaceFloat64(m.left().Value() - m.left().Value()); } if (m.IsFoldable()) { // K / K => K return ReplaceFloat64(m.left().Value() / m.right().Value()); } 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().Value())); 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 Replace(m.right().node()); } if (m.left().IsNaN()) { // NaN % x => NaN return Replace(m.left().node()); } if (m.IsFoldable()) { // K % K => K return ReplaceFloat64(modulo(m.left().Value(), m.right().Value())); } break; } case IrOpcode::kFloat64Acos: { Float64Matcher m(node->InputAt(0)); if (m.HasValue()) return ReplaceFloat64(base::ieee754::acos(m.Value())); break; } case IrOpcode::kFloat64Acosh: { Float64Matcher m(node->InputAt(0)); if (m.HasValue()) return ReplaceFloat64(base::ieee754::acosh(m.Value())); break; } case IrOpcode::kFloat64Asin: { Float64Matcher m(node->InputAt(0)); if (m.HasValue()) return ReplaceFloat64(base::ieee754::asin(m.Value())); break; } case IrOpcode::kFloat64Asinh: { Float64Matcher m(node->InputAt(0)); if (m.HasValue()) return ReplaceFloat64(base::ieee754::asinh(m.Value())); break; } case IrOpcode::kFloat64Atan: { Float64Matcher m(node->InputAt(0)); if (m.HasValue()) return ReplaceFloat64(base::ieee754::atan(m.Value())); break; } case IrOpcode::kFloat64Atanh: { Float64Matcher m(node->InputAt(0)); if (m.HasValue()) return ReplaceFloat64(base::ieee754::atanh(m.Value())); break; } case IrOpcode::kFloat64Atan2: { Float64BinopMatcher m(node); if (m.right().IsNaN()) { return Replace(m.right().node()); } if (m.left().IsNaN()) { return Replace(m.left().node()); } if (m.IsFoldable()) { return ReplaceFloat64( base::ieee754::atan2(m.left().Value(), m.right().Value())); } break; } case IrOpcode::kFloat64Cbrt: { Float64Matcher m(node->InputAt(0)); if (m.HasValue()) return ReplaceFloat64(base::ieee754::cbrt(m.Value())); break; } case IrOpcode::kFloat64Cos: { Float64Matcher m(node->InputAt(0)); if (m.HasValue()) return ReplaceFloat64(base::ieee754::cos(m.Value())); break; } case IrOpcode::kFloat64Cosh: { Float64Matcher m(node->InputAt(0)); if (m.HasValue()) return ReplaceFloat64(base::ieee754::cosh(m.Value())); break; } case IrOpcode::kFloat64Exp: { Float64Matcher m(node->InputAt(0)); if (m.HasValue()) return ReplaceFloat64(base::ieee754::exp(m.Value())); break; } case IrOpcode::kFloat64Expm1: { Float64Matcher m(node->InputAt(0)); if (m.HasValue()) return ReplaceFloat64(base::ieee754::expm1(m.Value())); break; } case IrOpcode::kFloat64Log: { Float64Matcher m(node->InputAt(0)); if (m.HasValue()) return ReplaceFloat64(base::ieee754::log(m.Value())); break; } case IrOpcode::kFloat64Log1p: { Float64Matcher m(node->InputAt(0)); if (m.HasValue()) return ReplaceFloat64(base::ieee754::log1p(m.Value())); break; } case IrOpcode::kFloat64Log10: { Float64Matcher m(node->InputAt(0)); if (m.HasValue()) return ReplaceFloat64(base::ieee754::log10(m.Value())); break; } case IrOpcode::kFloat64Log2: { Float64Matcher m(node->InputAt(0)); if (m.HasValue()) return ReplaceFloat64(base::ieee754::log2(m.Value())); break; } case IrOpcode::kFloat64Pow: { Float64BinopMatcher m(node); if (m.IsFoldable()) { return ReplaceFloat64(Pow(m.left().Value(), m.right().Value())); } 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 => 1 / (x * x) node->ReplaceInput(0, Float64Constant(1.0)); node->ReplaceInput(1, Float64Mul(m.left().node(), m.left().node())); NodeProperties::ChangeOp(node, machine()->Float64Div()); return Changed(node); } 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 => 1 / (if x <= -Infinity then Infinity else sqrt(0.0 + x)) node->ReplaceInput(0, Float64Constant(1.0)); node->ReplaceInput(1, Float64PowHalf(m.left().node())); NodeProperties::ChangeOp(node, machine()->Float64Div()); 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.HasValue()) return ReplaceFloat64(base::ieee754::sin(m.Value())); break; } case IrOpcode::kFloat64Sinh: { Float64Matcher m(node->InputAt(0)); if (m.HasValue()) return ReplaceFloat64(base::ieee754::sinh(m.Value())); break; } case IrOpcode::kFloat64Tan: { Float64Matcher m(node->InputAt(0)); if (m.HasValue()) return ReplaceFloat64(base::ieee754::tan(m.Value())); break; } case IrOpcode::kFloat64Tanh: { Float64Matcher m(node->InputAt(0)); if (m.HasValue()) return ReplaceFloat64(base::ieee754::tanh(m.Value())); break; } case IrOpcode::kChangeFloat32ToFloat64: { Float32Matcher m(node->InputAt(0)); if (m.HasValue()) { if (!allow_signalling_nan_ && std::isnan(m.Value())) { // Do some calculation to make guarantee the value is a quiet NaN. return ReplaceFloat64(m.Value() + m.Value()); } return ReplaceFloat64(m.Value()); } break; } case IrOpcode::kChangeFloat64ToInt32: { Float64Matcher m(node->InputAt(0)); if (m.HasValue()) return ReplaceInt32(FastD2I(m.Value())); if (m.IsChangeInt32ToFloat64()) return Replace(m.node()->InputAt(0)); break; } case IrOpcode::kChangeFloat64ToUint32: { Float64Matcher m(node->InputAt(0)); if (m.HasValue()) return ReplaceInt32(FastD2UI(m.Value())); if (m.IsChangeUint32ToFloat64()) return Replace(m.node()->InputAt(0)); break; } case IrOpcode::kChangeInt32ToFloat64: { Int32Matcher m(node->InputAt(0)); if (m.HasValue()) return ReplaceFloat64(FastI2D(m.Value())); break; } case IrOpcode::kChangeInt32ToInt64: { Int32Matcher m(node->InputAt(0)); if (m.HasValue()) return ReplaceInt64(m.Value()); break; } case IrOpcode::kChangeUint32ToFloat64: { Uint32Matcher m(node->InputAt(0)); if (m.HasValue()) return ReplaceFloat64(FastUI2D(m.Value())); break; } case IrOpcode::kChangeUint32ToUint64: { Uint32Matcher m(node->InputAt(0)); if (m.HasValue()) return ReplaceInt64(static_cast<uint64_t>(m.Value())); break; } case IrOpcode::kTruncateFloat64ToWord32: { Float64Matcher m(node->InputAt(0)); if (m.HasValue()) return ReplaceInt32(DoubleToInt32(m.Value())); if (m.IsChangeInt32ToFloat64()) return Replace(m.node()->InputAt(0)); return NoChange(); } case IrOpcode::kTruncateInt64ToInt32: { Int64Matcher m(node->InputAt(0)); if (m.HasValue()) return ReplaceInt32(static_cast<int32_t>(m.Value())); if (m.IsChangeInt32ToInt64()) return Replace(m.node()->InputAt(0)); break; } case IrOpcode::kTruncateFloat64ToFloat32: { Float64Matcher m(node->InputAt(0)); if (m.HasValue()) { if (!allow_signalling_nan_ && std::isnan(m.Value())) { // Do some calculation to make guarantee the value is a quiet NaN. return ReplaceFloat32(DoubleToFloat32(m.Value() + m.Value())); } return ReplaceFloat32(DoubleToFloat32(m.Value())); } if (allow_signalling_nan_ && m.IsChangeFloat32ToFloat64()) return Replace(m.node()->InputAt(0)); break; } case IrOpcode::kRoundFloat64ToInt32: { Float64Matcher m(node->InputAt(0)); if (m.HasValue()) return ReplaceInt32(static_cast<int32_t>(m.Value())); 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: case IrOpcode::kCheckedStore: return ReduceStore(node); case IrOpcode::kFloat64Equal: case IrOpcode::kFloat64LessThan: case IrOpcode::kFloat64LessThanOrEqual: return ReduceFloat64Compare(node); case IrOpcode::kFloat64RoundDown: return ReduceFloat64RoundDown(node); default: break; } 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 return ReplaceUint32(bit_cast<uint32_t>(m.left().Value()) + bit_cast<uint32_t>(m.right().Value())); } 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()); Reduction const reduction = ReduceInt32Sub(node); return reduction.Changed() ? reduction : Changed(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()); Reduction const reduction = ReduceInt32Sub(node); return reduction.Changed() ? reduction : 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 Replace(Uint64Constant(bit_cast<uint64_t>(m.left().Value()) + bit_cast<uint64_t>(m.right().Value()))); } 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 return ReplaceInt32(static_cast<uint32_t>(m.left().Value()) - static_cast<uint32_t>(m.right().Value())); } if (m.LeftEqualsRight()) return ReplaceInt32(0); // x - x => 0 if (m.right().HasValue()) { // x - K => x + -K node->ReplaceInput(1, Int32Constant(-m.right().Value())); NodeProperties::ChangeOp(node, machine()->Int32Add()); Reduction const reduction = ReduceInt32Add(node); return reduction.Changed() ? reduction : Changed(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 return Replace(Uint64Constant(bit_cast<uint64_t>(m.left().Value()) - bit_cast<uint64_t>(m.right().Value()))); } if (m.LeftEqualsRight()) return Replace(Int64Constant(0)); // x - x => 0 if (m.right().HasValue()) { // x - K => x + -K node->ReplaceInput(1, Int64Constant(-m.right().Value())); NodeProperties::ChangeOp(node, machine()->Int64Add()); Reduction const reduction = ReduceInt64Add(node); return reduction.Changed() ? reduction : 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 return ReplaceInt32( base::bits::SignedDiv32(m.left().Value(), m.right().Value())); } 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().HasValue()) { int32_t const divisor = m.right().Value(); Node* const dividend = m.left().node(); Node* quotient = dividend; if (base::bits::IsPowerOfTwo32(Abs(divisor))) { uint32_t const shift = WhichPowerOf2Abs(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 return ReplaceUint32( base::bits::UnsignedDiv32(m.left().Value(), m.right().Value())); } if (m.LeftEqualsRight()) { // x / x => x != 0 Node* const zero = Int32Constant(0); return Replace(Word32Equal(Word32Equal(m.left().node(), zero), zero)); } if (m.right().HasValue()) { Node* const dividend = m.left().node(); uint32_t const divisor = m.right().Value(); if (base::bits::IsPowerOfTwo32(divisor)) { // x / 2^n => x >> n node->ReplaceInput(1, Uint32Constant(WhichPowerOf2(m.right().Value()))); 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 return ReplaceInt32( base::bits::SignedMod32(m.left().Value(), m.right().Value())); } if (m.right().HasValue()) { Node* const dividend = m.left().node(); int32_t const divisor = Abs(m.right().Value()); if (base::bits::IsPowerOfTwo32(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 return ReplaceUint32( base::bits::UnsignedMod32(m.left().Value(), m.right().Value())); } if (m.right().HasValue()) { Node* const dividend = m.left().node(); uint32_t const divisor = m.right().Value(); if (base::bits::IsPowerOfTwo32(divisor)) { // x % 2^n => x & 2^n-1 node->ReplaceInput(1, Uint32Constant(m.right().Value() - 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.IsCheckedStore()) { rep = CheckedStoreRepresentationOf(node->op()); value_input = 3; } else 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().HasValue() && ((rep == MachineRepresentation::kWord8 && (m.right().Value() & 0xff) == 0xff) || (rep == MachineRepresentation::kWord16 && (m.right().Value() & 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().Value())) { 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().Value(), m.right().Value(), &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().Value(), m.right().Value(), &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().Value(), m.right().Value(), &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::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 return ReplaceInt32(m.left().Value() << m.right().Value()); } if (m.right().IsInRange(1, 31)) { // (x >>> K) << K => x & ~(2^K - 1) // (x >> K) << K => x & ~(2^K - 1) if (m.left().IsWord32Sar() || m.left().IsWord32Shr()) { Int32BinopMatcher mleft(m.left().node()); if (mleft.right().Is(m.right().Value())) { node->ReplaceInput(0, mleft.left().node()); node->ReplaceInput(1, Uint32Constant(~((1U << m.right().Value()) - 1U))); NodeProperties::ChangeOp(node, machine()->Word32And()); Reduction reduction = ReduceWord32And(node); return reduction.Changed() ? reduction : Changed(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 return ReplaceInt64(m.left().Value() << m.right().Value()); } 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 return ReplaceInt32(m.left().Value() >> m.right().Value()); } if (m.left().IsWord32And() && m.right().HasValue()) { Uint32BinopMatcher mleft(m.left().node()); if (mleft.right().HasValue()) { uint32_t shift = m.right().Value() & 0x1f; uint32_t mask = mleft.right().Value(); 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 return ReplaceInt64(m.left().Value() >> m.right().Value()); } 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 return ReplaceInt32(m.left().Value() >> m.right().Value()); } 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()); Reduction const reduction = ReduceInt32Sub(node); return reduction.Changed() ? reduction : Changed(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().Value() >> m.right().Value()); } return NoChange(); } Reduction MachineOperatorReducer::ReduceWord32And(Node* node) { DCHECK_EQ(IrOpcode::kWord32And, node->opcode()); 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.left().IsComparison() && m.right().Is(1)) { // CMP & 1 => CMP return Replace(m.left().node()); } if (m.IsFoldable()) { // K & K => K return ReplaceInt32(m.left().Value() & m.right().Value()); } if (m.LeftEqualsRight()) return Replace(m.left().node()); // x & x => x if (m.left().IsWord32And() && m.right().HasValue()) { Int32BinopMatcher mleft(m.left().node()); if (mleft.right().HasValue()) { // (x & K) & K => x & K node->ReplaceInput(0, mleft.left().node()); node->ReplaceInput( 1, Int32Constant(m.right().Value() & mleft.right().Value())); Reduction const reduction = ReduceWord32And(node); return reduction.Changed() ? reduction : Changed(node); } } if (m.right().IsNegativePowerOf2()) { int32_t const mask = m.right().Value(); if (m.left().IsWord32Shl()) { Uint32BinopMatcher mleft(m.left().node()); if (mleft.right().HasValue() && (mleft.right().Value() & 0x1f) >= base::bits::CountTrailingZeros32(mask)) { // (x << L) & (-1 << K) => x << L iff L >= K return Replace(mleft.node()); } } else if (m.left().IsInt32Add()) { Int32BinopMatcher mleft(m.left().node()); if (mleft.right().HasValue() && (mleft.right().Value() & mask) == mleft.right().Value()) { // (x + (K << L)) & (-1 << L) => (x & (-1 << L)) + (K << L) node->ReplaceInput(0, Word32And(mleft.left().node(), m.right().node())); node->ReplaceInput(1, mleft.right().node()); NodeProperties::ChangeOp(node, machine()->Int32Add()); Reduction const reduction = ReduceInt32Add(node); return reduction.Changed() ? reduction : Changed(node); } if (mleft.left().IsInt32Mul()) { Int32BinopMatcher mleftleft(mleft.left().node()); if (mleftleft.right().IsMultipleOf(-mask)) { // (y * (K << L) + x) & (-1 << L) => (x & (-1 << L)) + y * (K << L) node->ReplaceInput(0, Word32And(mleft.right().node(), m.right().node())); node->ReplaceInput(1, mleftleft.node()); NodeProperties::ChangeOp(node, machine()->Int32Add()); Reduction const reduction = ReduceInt32Add(node); return reduction.Changed() ? reduction : Changed(node); } } if (mleft.right().IsInt32Mul()) { Int32BinopMatcher mleftright(mleft.right().node()); if (mleftright.right().IsMultipleOf(-mask)) { // (x + y * (K << L)) & (-1 << L) => (x & (-1 << L)) + y * (K << L) node->ReplaceInput(0, Word32And(mleft.left().node(), m.right().node())); node->ReplaceInput(1, mleftright.node()); NodeProperties::ChangeOp(node, machine()->Int32Add()); Reduction const reduction = ReduceInt32Add(node); return reduction.Changed() ? reduction : Changed(node); } } if (mleft.left().IsWord32Shl()) { Int32BinopMatcher mleftleft(mleft.left().node()); if (mleftleft.right().Is(base::bits::CountTrailingZeros32(mask))) { // (y << L + x) & (-1 << L) => (x & (-1 << L)) + y << L node->ReplaceInput(0, Word32And(mleft.right().node(), m.right().node())); node->ReplaceInput(1, mleftleft.node()); NodeProperties::ChangeOp(node, machine()->Int32Add()); Reduction const reduction = ReduceInt32Add(node); return reduction.Changed() ? reduction : Changed(node); } } if (mleft.right().IsWord32Shl()) { Int32BinopMatcher mleftright(mleft.right().node()); if (mleftright.right().Is(base::bits::CountTrailingZeros32(mask))) { // (x + y << L) & (-1 << L) => (x & (-1 << L)) + y << L node->ReplaceInput(0, Word32And(mleft.left().node(), m.right().node())); node->ReplaceInput(1, mleftright.node()); NodeProperties::ChangeOp(node, machine()->Int32Add()); Reduction const reduction = ReduceInt32Add(node); return reduction.Changed() ? reduction : Changed(node); } } } else if (m.left().IsInt32Mul()) { Int32BinopMatcher mleft(m.left().node()); if (mleft.right().IsMultipleOf(-mask)) { // (x * (K << L)) & (-1 << L) => x * (K << L) return Replace(mleft.node()); } } } return NoChange(); } Reduction MachineOperatorReducer::TryMatchWord32Ror(Node* node) { DCHECK(IrOpcode::kWord32Or == node->opcode() || IrOpcode::kWord32Xor == node->opcode()); Int32BinopMatcher m(node); Node* shl = nullptr; Node* shr = nullptr; // Recognize rotation, we are matching: // * x << y | x >>> (32 - y) => x ror (32 - y), i.e x rol y // * x << (32 - y) | x >>> y => x ror y // * x << y ^ x >>> (32 - y) => x ror (32 - y), i.e. x rol y // * x << (32 - y) ^ x >>> y => x ror y // as well as their commuted form. 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().HasValue() && mshr.right().HasValue()) { // Case where y is a constant. if (mshl.right().Value() + mshr.right().Value() != 32) 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(); } node->ReplaceInput(0, mshl.left().node()); node->ReplaceInput(1, mshr.right().node()); NodeProperties::ChangeOp(node, machine()->Word32Ror()); return Changed(node); } Reduction MachineOperatorReducer::ReduceWord32Or(Node* node) { DCHECK_EQ(IrOpcode::kWord32Or, node->opcode()); Int32BinopMatcher 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 return ReplaceInt32(m.left().Value() | m.right().Value()); } if (m.LeftEqualsRight()) return Replace(m.left().node()); // x | x => x return TryMatchWord32Ror(node); } Reduction MachineOperatorReducer::ReduceWord32Xor(Node* node) { DCHECK_EQ(IrOpcode::kWord32Xor, node->opcode()); Int32BinopMatcher m(node); if (m.right().Is(0)) return Replace(m.left().node()); // x ^ 0 => x if (m.IsFoldable()) { // K ^ K => K return ReplaceInt32(m.left().Value() ^ m.right().Value()); } if (m.LeftEqualsRight()) return ReplaceInt32(0); // x ^ x => 0 if (m.left().IsWord32Xor() && m.right().Is(-1)) { Int32BinopMatcher mleft(m.left().node()); if (mleft.right().Is(-1)) { // (x ^ -1) ^ -1 => x return Replace(mleft.left().node()); } } return TryMatchWord32Ror(node); } Reduction MachineOperatorReducer::ReduceFloat64InsertLowWord32(Node* node) { DCHECK_EQ(IrOpcode::kFloat64InsertLowWord32, node->opcode()); Float64Matcher mlhs(node->InputAt(0)); Uint32Matcher mrhs(node->InputAt(1)); if (mlhs.HasValue() && mrhs.HasValue()) { return ReplaceFloat64(bit_cast<double>( (bit_cast<uint64_t>(mlhs.Value()) & V8_UINT64_C(0xFFFFFFFF00000000)) | mrhs.Value())); } 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.HasValue() && mrhs.HasValue()) { return ReplaceFloat64(bit_cast<double>( (bit_cast<uint64_t>(mlhs.Value()) & V8_UINT64_C(0xFFFFFFFF)) | (static_cast<uint64_t>(mrhs.Value()) << 32))); } return NoChange(); } namespace { bool IsFloat64RepresentableAsFloat32(const Float64Matcher& m) { if (m.HasValue()) { double v = m.Value(); float fv = static_cast<float>(v); return static_cast<double>(fv) == v; } return false; } } // namespace Reduction MachineOperatorReducer::ReduceFloat64Compare(Node* node) { DCHECK((IrOpcode::kFloat64Equal == node->opcode()) || (IrOpcode::kFloat64LessThan == node->opcode()) || (IrOpcode::kFloat64LessThanOrEqual == node->opcode())); // 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. Float64BinopMatcher m(node); if ((m.left().IsChangeFloat32ToFloat64() && m.right().IsChangeFloat32ToFloat64()) || (m.left().IsChangeFloat32ToFloat64() && IsFloat64RepresentableAsFloat32(m.right())) || (IsFloat64RepresentableAsFloat32(m.left()) && m.right().IsChangeFloat32ToFloat64())) { 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: return NoChange(); } node->ReplaceInput( 0, m.left().HasValue() ? Float32Constant(static_cast<float>(m.left().Value())) : m.left().InputAt(0)); node->ReplaceInput( 1, m.right().HasValue() ? Float32Constant(static_cast<float>(m.right().Value())) : 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.HasValue()) { return ReplaceFloat64(Floor(m.Value())); } return NoChange(); } CommonOperatorBuilder* MachineOperatorReducer::common() const { return jsgraph()->common(); } MachineOperatorBuilder* MachineOperatorReducer::machine() const { return jsgraph()->machine(); } Graph* MachineOperatorReducer::graph() const { return jsgraph()->graph(); } } // namespace compiler } // namespace internal } // namespace v8