1 // Copyright 2014 the V8 project authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
5 #include "src/compiler/machine-operator-reducer.h"
7 #include "src/base/bits.h"
8 #include "src/base/division-by-constant.h"
9 #include "src/codegen.h"
10 #include "src/compiler/diamond.h"
11 #include "src/compiler/graph.h"
12 #include "src/compiler/js-graph.h"
13 #include "src/compiler/node-matchers.h"
19 MachineOperatorReducer::MachineOperatorReducer(JSGraph* jsgraph)
20 : jsgraph_(jsgraph) {}
23 MachineOperatorReducer::~MachineOperatorReducer() {}
26 Node* MachineOperatorReducer::Float32Constant(volatile float value) {
27 return graph()->NewNode(common()->Float32Constant(value));
31 Node* MachineOperatorReducer::Float64Constant(volatile double value) {
32 return jsgraph()->Float64Constant(value);
36 Node* MachineOperatorReducer::Int32Constant(int32_t value) {
37 return jsgraph()->Int32Constant(value);
41 Node* MachineOperatorReducer::Int64Constant(int64_t value) {
42 return graph()->NewNode(common()->Int64Constant(value));
46 Node* MachineOperatorReducer::Word32And(Node* lhs, Node* rhs) {
47 Node* const node = graph()->NewNode(machine()->Word32And(), lhs, rhs);
48 Reduction const reduction = ReduceWord32And(node);
49 return reduction.Changed() ? reduction.replacement() : node;
53 Node* MachineOperatorReducer::Word32Sar(Node* lhs, uint32_t rhs) {
54 if (rhs == 0) return lhs;
55 return graph()->NewNode(machine()->Word32Sar(), lhs, Uint32Constant(rhs));
59 Node* MachineOperatorReducer::Word32Shr(Node* lhs, uint32_t rhs) {
60 if (rhs == 0) return lhs;
61 return graph()->NewNode(machine()->Word32Shr(), lhs, Uint32Constant(rhs));
65 Node* MachineOperatorReducer::Word32Equal(Node* lhs, Node* rhs) {
66 return graph()->NewNode(machine()->Word32Equal(), lhs, rhs);
70 Node* MachineOperatorReducer::Int32Add(Node* lhs, Node* rhs) {
71 Node* const node = graph()->NewNode(machine()->Int32Add(), lhs, rhs);
72 Reduction const reduction = ReduceInt32Add(node);
73 return reduction.Changed() ? reduction.replacement() : node;
77 Node* MachineOperatorReducer::Int32Sub(Node* lhs, Node* rhs) {
78 Node* const node = graph()->NewNode(machine()->Int32Sub(), lhs, rhs);
79 Reduction const reduction = ReduceInt32Sub(node);
80 return reduction.Changed() ? reduction.replacement() : node;
84 Node* MachineOperatorReducer::Int32Mul(Node* lhs, Node* rhs) {
85 return graph()->NewNode(machine()->Int32Mul(), lhs, rhs);
89 Node* MachineOperatorReducer::Int32Div(Node* dividend, int32_t divisor) {
90 DCHECK_NE(0, divisor);
91 DCHECK_NE(std::numeric_limits<int32_t>::min(), divisor);
92 base::MagicNumbersForDivision<uint32_t> const mag =
93 base::SignedDivisionByConstant(bit_cast<uint32_t>(divisor));
94 Node* quotient = graph()->NewNode(machine()->Int32MulHigh(), dividend,
95 Uint32Constant(mag.multiplier));
96 if (divisor > 0 && bit_cast<int32_t>(mag.multiplier) < 0) {
97 quotient = Int32Add(quotient, dividend);
98 } else if (divisor < 0 && bit_cast<int32_t>(mag.multiplier) > 0) {
99 quotient = Int32Sub(quotient, dividend);
101 return Int32Add(Word32Sar(quotient, mag.shift), Word32Shr(dividend, 31));
105 Node* MachineOperatorReducer::Uint32Div(Node* dividend, uint32_t divisor) {
106 DCHECK_LT(0u, divisor);
107 // If the divisor is even, we can avoid using the expensive fixup by shifting
108 // the dividend upfront.
109 unsigned const shift = base::bits::CountTrailingZeros32(divisor);
110 dividend = Word32Shr(dividend, shift);
112 // Compute the magic number for the (shifted) divisor.
113 base::MagicNumbersForDivision<uint32_t> const mag =
114 base::UnsignedDivisionByConstant(divisor, shift);
115 Node* quotient = graph()->NewNode(machine()->Uint32MulHigh(), dividend,
116 Uint32Constant(mag.multiplier));
118 DCHECK_LE(1u, mag.shift);
119 quotient = Word32Shr(
120 Int32Add(Word32Shr(Int32Sub(dividend, quotient), 1), quotient),
123 quotient = Word32Shr(quotient, mag.shift);
129 // Perform constant folding and strength reduction on machine operators.
130 Reduction MachineOperatorReducer::Reduce(Node* node) {
131 switch (node->opcode()) {
132 case IrOpcode::kProjection:
133 return ReduceProjection(ProjectionIndexOf(node->op()), node->InputAt(0));
134 case IrOpcode::kWord32And:
135 return ReduceWord32And(node);
136 case IrOpcode::kWord32Or:
137 return ReduceWord32Or(node);
138 case IrOpcode::kWord32Xor: {
139 Int32BinopMatcher m(node);
140 if (m.right().Is(0)) return Replace(m.left().node()); // x ^ 0 => x
141 if (m.IsFoldable()) { // K ^ K => K
142 return ReplaceInt32(m.left().Value() ^ m.right().Value());
144 if (m.LeftEqualsRight()) return ReplaceInt32(0); // x ^ x => 0
145 if (m.left().IsWord32Xor() && m.right().Is(-1)) {
146 Int32BinopMatcher mleft(m.left().node());
147 if (mleft.right().Is(-1)) { // (x ^ -1) ^ -1 => x
148 return Replace(mleft.left().node());
153 case IrOpcode::kWord32Shl:
154 return ReduceWord32Shl(node);
155 case IrOpcode::kWord32Shr: {
156 Uint32BinopMatcher m(node);
157 if (m.right().Is(0)) return Replace(m.left().node()); // x >>> 0 => x
158 if (m.IsFoldable()) { // K >>> K => K
159 return ReplaceInt32(m.left().Value() >> m.right().Value());
161 return ReduceWord32Shifts(node);
163 case IrOpcode::kWord32Sar:
164 return ReduceWord32Sar(node);
165 case IrOpcode::kWord32Ror: {
166 Int32BinopMatcher m(node);
167 if (m.right().Is(0)) return Replace(m.left().node()); // x ror 0 => x
168 if (m.IsFoldable()) { // K ror K => K
170 base::bits::RotateRight32(m.left().Value(), m.right().Value()));
174 case IrOpcode::kWord32Equal: {
175 Int32BinopMatcher m(node);
176 if (m.IsFoldable()) { // K == K => K
177 return ReplaceBool(m.left().Value() == m.right().Value());
179 if (m.left().IsInt32Sub() && m.right().Is(0)) { // x - y == 0 => x == y
180 Int32BinopMatcher msub(m.left().node());
181 node->ReplaceInput(0, msub.left().node());
182 node->ReplaceInput(1, msub.right().node());
183 return Changed(node);
185 // TODO(turbofan): fold HeapConstant, ExternalReference, pointer compares
186 if (m.LeftEqualsRight()) return ReplaceBool(true); // x == x => true
189 case IrOpcode::kWord64Equal: {
190 Int64BinopMatcher m(node);
191 if (m.IsFoldable()) { // K == K => K
192 return ReplaceBool(m.left().Value() == m.right().Value());
194 if (m.left().IsInt64Sub() && m.right().Is(0)) { // x - y == 0 => x == y
195 Int64BinopMatcher msub(m.left().node());
196 node->ReplaceInput(0, msub.left().node());
197 node->ReplaceInput(1, msub.right().node());
198 return Changed(node);
200 // TODO(turbofan): fold HeapConstant, ExternalReference, pointer compares
201 if (m.LeftEqualsRight()) return ReplaceBool(true); // x == x => true
204 case IrOpcode::kInt32Add:
205 return ReduceInt32Add(node);
206 case IrOpcode::kInt32Sub:
207 return ReduceInt32Sub(node);
208 case IrOpcode::kInt32Mul: {
209 Int32BinopMatcher m(node);
210 if (m.right().Is(0)) return Replace(m.right().node()); // x * 0 => 0
211 if (m.right().Is(1)) return Replace(m.left().node()); // x * 1 => x
212 if (m.IsFoldable()) { // K * K => K
213 return ReplaceInt32(m.left().Value() * m.right().Value());
215 if (m.right().Is(-1)) { // x * -1 => 0 - x
216 node->set_op(machine()->Int32Sub());
217 node->ReplaceInput(0, Int32Constant(0));
218 node->ReplaceInput(1, m.left().node());
219 return Changed(node);
221 if (m.right().IsPowerOf2()) { // x * 2^n => x << n
222 node->set_op(machine()->Word32Shl());
223 node->ReplaceInput(1, Int32Constant(WhichPowerOf2(m.right().Value())));
224 Reduction reduction = ReduceWord32Shl(node);
225 return reduction.Changed() ? reduction : Changed(node);
229 case IrOpcode::kInt32Div:
230 return ReduceInt32Div(node);
231 case IrOpcode::kUint32Div:
232 return ReduceUint32Div(node);
233 case IrOpcode::kInt32Mod:
234 return ReduceInt32Mod(node);
235 case IrOpcode::kUint32Mod:
236 return ReduceUint32Mod(node);
237 case IrOpcode::kInt32LessThan: {
238 Int32BinopMatcher m(node);
239 if (m.IsFoldable()) { // K < K => K
240 return ReplaceBool(m.left().Value() < m.right().Value());
242 if (m.left().IsInt32Sub() && m.right().Is(0)) { // x - y < 0 => x < y
243 Int32BinopMatcher msub(m.left().node());
244 node->ReplaceInput(0, msub.left().node());
245 node->ReplaceInput(1, msub.right().node());
246 return Changed(node);
248 if (m.left().Is(0) && m.right().IsInt32Sub()) { // 0 < x - y => y < x
249 Int32BinopMatcher msub(m.right().node());
250 node->ReplaceInput(0, msub.right().node());
251 node->ReplaceInput(1, msub.left().node());
252 return Changed(node);
254 if (m.LeftEqualsRight()) return ReplaceBool(false); // x < x => false
257 case IrOpcode::kInt32LessThanOrEqual: {
258 Int32BinopMatcher m(node);
259 if (m.IsFoldable()) { // K <= K => K
260 return ReplaceBool(m.left().Value() <= m.right().Value());
262 if (m.left().IsInt32Sub() && m.right().Is(0)) { // x - y <= 0 => x <= y
263 Int32BinopMatcher msub(m.left().node());
264 node->ReplaceInput(0, msub.left().node());
265 node->ReplaceInput(1, msub.right().node());
266 return Changed(node);
268 if (m.left().Is(0) && m.right().IsInt32Sub()) { // 0 <= x - y => y <= x
269 Int32BinopMatcher msub(m.right().node());
270 node->ReplaceInput(0, msub.right().node());
271 node->ReplaceInput(1, msub.left().node());
272 return Changed(node);
274 if (m.LeftEqualsRight()) return ReplaceBool(true); // x <= x => true
277 case IrOpcode::kUint32LessThan: {
278 Uint32BinopMatcher m(node);
279 if (m.left().Is(kMaxUInt32)) return ReplaceBool(false); // M < x => false
280 if (m.right().Is(0)) return ReplaceBool(false); // x < 0 => false
281 if (m.IsFoldable()) { // K < K => K
282 return ReplaceBool(m.left().Value() < m.right().Value());
284 if (m.LeftEqualsRight()) return ReplaceBool(false); // x < x => false
285 if (m.left().IsWord32Sar() && m.right().HasValue()) {
286 Int32BinopMatcher mleft(m.left().node());
287 if (mleft.right().HasValue()) {
288 // (x >> K) < C => x < (C << K)
290 const uint32_t c = m.right().Value();
291 const uint32_t k = mleft.right().Value() & 0x1f;
292 if (c < static_cast<uint32_t>(kMaxInt >> k)) {
293 node->ReplaceInput(0, mleft.left().node());
294 node->ReplaceInput(1, Uint32Constant(c << k));
295 return Changed(node);
297 // TODO(turbofan): else the comparison is always true.
302 case IrOpcode::kUint32LessThanOrEqual: {
303 Uint32BinopMatcher m(node);
304 if (m.left().Is(0)) return ReplaceBool(true); // 0 <= x => true
305 if (m.right().Is(kMaxUInt32)) return ReplaceBool(true); // x <= M => true
306 if (m.IsFoldable()) { // K <= K => K
307 return ReplaceBool(m.left().Value() <= m.right().Value());
309 if (m.LeftEqualsRight()) return ReplaceBool(true); // x <= x => true
312 case IrOpcode::kFloat64Add: {
313 Float64BinopMatcher m(node);
314 if (m.right().IsNaN()) { // x + NaN => NaN
315 return Replace(m.right().node());
317 if (m.IsFoldable()) { // K + K => K
318 return ReplaceFloat64(m.left().Value() + m.right().Value());
322 case IrOpcode::kFloat64Sub: {
323 Float64BinopMatcher m(node);
324 if (m.right().Is(0) && (Double(m.right().Value()).Sign() > 0)) {
325 return Replace(m.left().node()); // x - 0 => x
327 if (m.right().IsNaN()) { // x - NaN => NaN
328 return Replace(m.right().node());
330 if (m.left().IsNaN()) { // NaN - x => NaN
331 return Replace(m.left().node());
333 if (m.IsFoldable()) { // K - K => K
334 return ReplaceFloat64(m.left().Value() - m.right().Value());
338 case IrOpcode::kFloat64Mul: {
339 Float64BinopMatcher m(node);
340 if (m.right().Is(-1)) { // x * -1.0 => -0.0 - x
341 node->set_op(machine()->Float64Sub());
342 node->ReplaceInput(0, Float64Constant(-0.0));
343 node->ReplaceInput(1, m.left().node());
344 return Changed(node);
346 if (m.right().Is(1)) return Replace(m.left().node()); // x * 1.0 => x
347 if (m.right().IsNaN()) { // x * NaN => NaN
348 return Replace(m.right().node());
350 if (m.IsFoldable()) { // K * K => K
351 return ReplaceFloat64(m.left().Value() * m.right().Value());
355 case IrOpcode::kFloat64Div: {
356 Float64BinopMatcher m(node);
357 if (m.right().Is(1)) return Replace(m.left().node()); // x / 1.0 => x
358 if (m.right().IsNaN()) { // x / NaN => NaN
359 return Replace(m.right().node());
361 if (m.left().IsNaN()) { // NaN / x => NaN
362 return Replace(m.left().node());
364 if (m.IsFoldable()) { // K / K => K
365 return ReplaceFloat64(m.left().Value() / m.right().Value());
369 case IrOpcode::kFloat64Mod: {
370 Float64BinopMatcher m(node);
371 if (m.right().Is(0)) { // x % 0 => NaN
372 return ReplaceFloat64(std::numeric_limits<double>::quiet_NaN());
374 if (m.right().IsNaN()) { // x % NaN => NaN
375 return Replace(m.right().node());
377 if (m.left().IsNaN()) { // NaN % x => NaN
378 return Replace(m.left().node());
380 if (m.IsFoldable()) { // K % K => K
381 return ReplaceFloat64(modulo(m.left().Value(), m.right().Value()));
385 case IrOpcode::kChangeFloat32ToFloat64: {
386 Float32Matcher m(node->InputAt(0));
387 if (m.HasValue()) return ReplaceFloat64(m.Value());
390 case IrOpcode::kChangeFloat64ToInt32: {
391 Float64Matcher m(node->InputAt(0));
392 if (m.HasValue()) return ReplaceInt32(FastD2I(m.Value()));
393 if (m.IsChangeInt32ToFloat64()) return Replace(m.node()->InputAt(0));
396 case IrOpcode::kChangeFloat64ToUint32: {
397 Float64Matcher m(node->InputAt(0));
398 if (m.HasValue()) return ReplaceInt32(FastD2UI(m.Value()));
399 if (m.IsChangeUint32ToFloat64()) return Replace(m.node()->InputAt(0));
402 case IrOpcode::kChangeInt32ToFloat64: {
403 Int32Matcher m(node->InputAt(0));
404 if (m.HasValue()) return ReplaceFloat64(FastI2D(m.Value()));
407 case IrOpcode::kChangeInt32ToInt64: {
408 Int32Matcher m(node->InputAt(0));
409 if (m.HasValue()) return ReplaceInt64(m.Value());
412 case IrOpcode::kChangeUint32ToFloat64: {
413 Uint32Matcher m(node->InputAt(0));
414 if (m.HasValue()) return ReplaceFloat64(FastUI2D(m.Value()));
417 case IrOpcode::kChangeUint32ToUint64: {
418 Uint32Matcher m(node->InputAt(0));
419 if (m.HasValue()) return ReplaceInt64(static_cast<uint64_t>(m.Value()));
422 case IrOpcode::kTruncateFloat64ToInt32:
423 return ReduceTruncateFloat64ToInt32(node);
424 case IrOpcode::kTruncateInt64ToInt32: {
425 Int64Matcher m(node->InputAt(0));
426 if (m.HasValue()) return ReplaceInt32(static_cast<int32_t>(m.Value()));
427 if (m.IsChangeInt32ToInt64()) return Replace(m.node()->InputAt(0));
430 case IrOpcode::kTruncateFloat64ToFloat32: {
431 Float64Matcher m(node->InputAt(0));
432 if (m.HasValue()) return ReplaceFloat32(DoubleToFloat32(m.Value()));
433 if (m.IsChangeFloat32ToFloat64()) return Replace(m.node()->InputAt(0));
436 case IrOpcode::kFloat64InsertLowWord32:
437 return ReduceFloat64InsertLowWord32(node);
438 case IrOpcode::kFloat64InsertHighWord32:
439 return ReduceFloat64InsertHighWord32(node);
440 case IrOpcode::kStore:
441 return ReduceStore(node);
449 Reduction MachineOperatorReducer::ReduceInt32Add(Node* node) {
450 DCHECK_EQ(IrOpcode::kInt32Add, node->opcode());
451 Int32BinopMatcher m(node);
452 if (m.right().Is(0)) return Replace(m.left().node()); // x + 0 => x
453 if (m.IsFoldable()) { // K + K => K
454 return ReplaceUint32(bit_cast<uint32_t>(m.left().Value()) +
455 bit_cast<uint32_t>(m.right().Value()));
457 if (m.left().IsInt32Sub()) {
458 Int32BinopMatcher mleft(m.left().node());
459 if (mleft.left().Is(0)) { // (0 - x) + y => y - x
460 node->set_op(machine()->Int32Sub());
461 node->ReplaceInput(0, m.right().node());
462 node->ReplaceInput(1, mleft.right().node());
463 Reduction const reduction = ReduceInt32Sub(node);
464 return reduction.Changed() ? reduction : Changed(node);
467 if (m.right().IsInt32Sub()) {
468 Int32BinopMatcher mright(m.right().node());
469 if (mright.left().Is(0)) { // y + (0 - x) => y - x
470 node->set_op(machine()->Int32Sub());
471 node->ReplaceInput(1, mright.right().node());
472 Reduction const reduction = ReduceInt32Sub(node);
473 return reduction.Changed() ? reduction : Changed(node);
480 Reduction MachineOperatorReducer::ReduceInt32Sub(Node* node) {
481 DCHECK_EQ(IrOpcode::kInt32Sub, node->opcode());
482 Int32BinopMatcher m(node);
483 if (m.right().Is(0)) return Replace(m.left().node()); // x - 0 => x
484 if (m.IsFoldable()) { // K - K => K
485 return ReplaceInt32(static_cast<uint32_t>(m.left().Value()) -
486 static_cast<uint32_t>(m.right().Value()));
488 if (m.LeftEqualsRight()) return ReplaceInt32(0); // x - x => 0
489 if (m.right().HasValue()) { // x - K => x + -K
490 node->set_op(machine()->Int32Add());
491 node->ReplaceInput(1, Int32Constant(-m.right().Value()));
492 Reduction const reduction = ReduceInt32Add(node);
493 return reduction.Changed() ? reduction : Changed(node);
499 Reduction MachineOperatorReducer::ReduceInt32Div(Node* node) {
500 Int32BinopMatcher m(node);
501 if (m.left().Is(0)) return Replace(m.left().node()); // 0 / x => 0
502 if (m.right().Is(0)) return Replace(m.right().node()); // x / 0 => 0
503 if (m.right().Is(1)) return Replace(m.left().node()); // x / 1 => x
504 if (m.IsFoldable()) { // K / K => K
506 base::bits::SignedDiv32(m.left().Value(), m.right().Value()));
508 if (m.LeftEqualsRight()) { // x / x => x != 0
509 Node* const zero = Int32Constant(0);
510 return Replace(Word32Equal(Word32Equal(m.left().node(), zero), zero));
512 if (m.right().Is(-1)) { // x / -1 => 0 - x
513 node->set_op(machine()->Int32Sub());
514 node->ReplaceInput(0, Int32Constant(0));
515 node->ReplaceInput(1, m.left().node());
516 node->TrimInputCount(2);
517 return Changed(node);
519 if (m.right().HasValue()) {
520 int32_t const divisor = m.right().Value();
521 Node* const dividend = m.left().node();
522 Node* quotient = dividend;
523 if (base::bits::IsPowerOfTwo32(Abs(divisor))) {
524 uint32_t const shift = WhichPowerOf2Abs(divisor);
525 DCHECK_NE(0u, shift);
527 quotient = Word32Sar(quotient, 31);
529 quotient = Int32Add(Word32Shr(quotient, 32u - shift), dividend);
530 quotient = Word32Sar(quotient, shift);
532 quotient = Int32Div(quotient, Abs(divisor));
535 node->set_op(machine()->Int32Sub());
536 node->ReplaceInput(0, Int32Constant(0));
537 node->ReplaceInput(1, quotient);
538 node->TrimInputCount(2);
539 return Changed(node);
541 return Replace(quotient);
547 Reduction MachineOperatorReducer::ReduceUint32Div(Node* node) {
548 Uint32BinopMatcher m(node);
549 if (m.left().Is(0)) return Replace(m.left().node()); // 0 / x => 0
550 if (m.right().Is(0)) return Replace(m.right().node()); // x / 0 => 0
551 if (m.right().Is(1)) return Replace(m.left().node()); // x / 1 => x
552 if (m.IsFoldable()) { // K / K => K
553 return ReplaceUint32(
554 base::bits::UnsignedDiv32(m.left().Value(), m.right().Value()));
556 if (m.LeftEqualsRight()) { // x / x => x != 0
557 Node* const zero = Int32Constant(0);
558 return Replace(Word32Equal(Word32Equal(m.left().node(), zero), zero));
560 if (m.right().HasValue()) {
561 Node* const dividend = m.left().node();
562 uint32_t const divisor = m.right().Value();
563 if (base::bits::IsPowerOfTwo32(divisor)) { // x / 2^n => x >> n
564 node->set_op(machine()->Word32Shr());
565 node->ReplaceInput(1, Uint32Constant(WhichPowerOf2(m.right().Value())));
566 node->TrimInputCount(2);
567 return Changed(node);
569 return Replace(Uint32Div(dividend, divisor));
576 Reduction MachineOperatorReducer::ReduceInt32Mod(Node* node) {
577 Int32BinopMatcher m(node);
578 if (m.left().Is(0)) return Replace(m.left().node()); // 0 % x => 0
579 if (m.right().Is(0)) return Replace(m.right().node()); // x % 0 => 0
580 if (m.right().Is(1)) return ReplaceInt32(0); // x % 1 => 0
581 if (m.right().Is(-1)) return ReplaceInt32(0); // x % -1 => 0
582 if (m.LeftEqualsRight()) return ReplaceInt32(0); // x % x => 0
583 if (m.IsFoldable()) { // K % K => K
585 base::bits::SignedMod32(m.left().Value(), m.right().Value()));
587 if (m.right().HasValue()) {
588 Node* const dividend = m.left().node();
589 int32_t const divisor = Abs(m.right().Value());
590 if (base::bits::IsPowerOfTwo32(divisor)) {
591 uint32_t const mask = divisor - 1;
592 Node* const zero = Int32Constant(0);
593 node->set_op(common()->Select(kMachInt32, BranchHint::kFalse));
595 0, graph()->NewNode(machine()->Int32LessThan(), dividend, zero));
597 1, Int32Sub(zero, Word32And(Int32Sub(zero, dividend), mask)));
598 node->ReplaceInput(2, Word32And(dividend, mask));
600 Node* quotient = Int32Div(dividend, divisor);
601 node->set_op(machine()->Int32Sub());
602 DCHECK_EQ(dividend, node->InputAt(0));
603 node->ReplaceInput(1, Int32Mul(quotient, Int32Constant(divisor)));
604 node->TrimInputCount(2);
606 return Changed(node);
612 Reduction MachineOperatorReducer::ReduceUint32Mod(Node* node) {
613 Uint32BinopMatcher m(node);
614 if (m.left().Is(0)) return Replace(m.left().node()); // 0 % x => 0
615 if (m.right().Is(0)) return Replace(m.right().node()); // x % 0 => 0
616 if (m.right().Is(1)) return ReplaceUint32(0); // x % 1 => 0
617 if (m.LeftEqualsRight()) return ReplaceInt32(0); // x % x => 0
618 if (m.IsFoldable()) { // K % K => K
619 return ReplaceUint32(
620 base::bits::UnsignedMod32(m.left().Value(), m.right().Value()));
622 if (m.right().HasValue()) {
623 Node* const dividend = m.left().node();
624 uint32_t const divisor = m.right().Value();
625 if (base::bits::IsPowerOfTwo32(divisor)) { // x % 2^n => x & 2^n-1
626 node->set_op(machine()->Word32And());
627 node->ReplaceInput(1, Uint32Constant(m.right().Value() - 1));
629 Node* quotient = Uint32Div(dividend, divisor);
630 node->set_op(machine()->Int32Sub());
631 DCHECK_EQ(dividend, node->InputAt(0));
632 node->ReplaceInput(1, Int32Mul(quotient, Uint32Constant(divisor)));
634 node->TrimInputCount(2);
635 return Changed(node);
641 Reduction MachineOperatorReducer::ReduceTruncateFloat64ToInt32(Node* node) {
642 Float64Matcher m(node->InputAt(0));
643 if (m.HasValue()) return ReplaceInt32(DoubleToInt32(m.Value()));
644 if (m.IsChangeInt32ToFloat64()) return Replace(m.node()->InputAt(0));
646 Node* const phi = m.node();
647 DCHECK_EQ(kRepFloat64, RepresentationOf(OpParameter<MachineType>(phi)));
648 if (phi->OwnedBy(node)) {
649 // TruncateFloat64ToInt32(Phi[Float64](x1,...,xn))
650 // => Phi[Int32](TruncateFloat64ToInt32(x1),
652 // TruncateFloat64ToInt32(xn))
653 const int value_input_count = phi->InputCount() - 1;
654 for (int i = 0; i < value_input_count; ++i) {
655 Node* input = graph()->NewNode(machine()->TruncateFloat64ToInt32(),
657 // TODO(bmeurer): Reschedule input for reduction once we have Revisit()
658 // instead of recursing into ReduceTruncateFloat64ToInt32() here.
659 Reduction reduction = ReduceTruncateFloat64ToInt32(input);
660 if (reduction.Changed()) input = reduction.replacement();
661 phi->ReplaceInput(i, input);
663 phi->set_op(common()->Phi(kMachInt32, value_input_count));
671 Reduction MachineOperatorReducer::ReduceStore(Node* node) {
672 MachineType const rep =
673 RepresentationOf(StoreRepresentationOf(node->op()).machine_type());
674 Node* const value = node->InputAt(2);
675 switch (value->opcode()) {
676 case IrOpcode::kWord32And: {
677 Uint32BinopMatcher m(value);
678 if (m.right().HasValue() &&
679 ((rep == kRepWord8 && (m.right().Value() & 0xff) == 0xff) ||
680 (rep == kRepWord16 && (m.right().Value() & 0xffff) == 0xffff))) {
681 node->ReplaceInput(2, m.left().node());
682 return Changed(node);
686 case IrOpcode::kWord32Sar: {
687 Int32BinopMatcher m(value);
688 if (m.left().IsWord32Shl() &&
689 ((rep == kRepWord8 && m.right().IsInRange(1, 24)) ||
690 (rep == kRepWord16 && m.right().IsInRange(1, 16)))) {
691 Int32BinopMatcher mleft(m.left().node());
692 if (mleft.right().Is(m.right().Value())) {
693 node->ReplaceInput(2, mleft.left().node());
694 return Changed(node);
706 Reduction MachineOperatorReducer::ReduceProjection(size_t index, Node* node) {
707 switch (node->opcode()) {
708 case IrOpcode::kInt32AddWithOverflow: {
709 DCHECK(index == 0 || index == 1);
710 Int32BinopMatcher m(node);
711 if (m.IsFoldable()) {
713 bool ovf = base::bits::SignedAddOverflow32(m.left().Value(),
714 m.right().Value(), &val);
715 return ReplaceInt32((index == 0) ? val : ovf);
717 if (m.right().Is(0)) {
718 return (index == 0) ? Replace(m.left().node()) : ReplaceInt32(0);
722 case IrOpcode::kInt32SubWithOverflow: {
723 DCHECK(index == 0 || index == 1);
724 Int32BinopMatcher m(node);
725 if (m.IsFoldable()) {
727 bool ovf = base::bits::SignedSubOverflow32(m.left().Value(),
728 m.right().Value(), &val);
729 return ReplaceInt32((index == 0) ? val : ovf);
731 if (m.right().Is(0)) {
732 return (index == 0) ? Replace(m.left().node()) : ReplaceInt32(0);
743 Reduction MachineOperatorReducer::ReduceWord32Shifts(Node* node) {
744 DCHECK((node->opcode() == IrOpcode::kWord32Shl) ||
745 (node->opcode() == IrOpcode::kWord32Shr) ||
746 (node->opcode() == IrOpcode::kWord32Sar));
747 if (machine()->Word32ShiftIsSafe()) {
748 // Remove the explicit 'and' with 0x1f if the shift provided by the machine
749 // instruction matches that required by JavaScript.
750 Int32BinopMatcher m(node);
751 if (m.right().IsWord32And()) {
752 Int32BinopMatcher mright(m.right().node());
753 if (mright.right().Is(0x1f)) {
754 node->ReplaceInput(1, mright.left().node());
755 return Changed(node);
763 Reduction MachineOperatorReducer::ReduceWord32Shl(Node* node) {
764 DCHECK_EQ(IrOpcode::kWord32Shl, node->opcode());
765 Int32BinopMatcher m(node);
766 if (m.right().Is(0)) return Replace(m.left().node()); // x << 0 => x
767 if (m.IsFoldable()) { // K << K => K
768 return ReplaceInt32(m.left().Value() << m.right().Value());
770 if (m.right().IsInRange(1, 31)) {
771 // (x >>> K) << K => x & ~(2^K - 1)
772 // (x >> K) << K => x & ~(2^K - 1)
773 if (m.left().IsWord32Sar() || m.left().IsWord32Shr()) {
774 Int32BinopMatcher mleft(m.left().node());
775 if (mleft.right().Is(m.right().Value())) {
776 node->set_op(machine()->Word32And());
777 node->ReplaceInput(0, mleft.left().node());
778 node->ReplaceInput(1,
779 Uint32Constant(~((1U << m.right().Value()) - 1U)));
780 Reduction reduction = ReduceWord32And(node);
781 return reduction.Changed() ? reduction : Changed(node);
785 return ReduceWord32Shifts(node);
789 Reduction MachineOperatorReducer::ReduceWord32Sar(Node* node) {
790 Int32BinopMatcher m(node);
791 if (m.right().Is(0)) return Replace(m.left().node()); // x >> 0 => x
792 if (m.IsFoldable()) { // K >> K => K
793 return ReplaceInt32(m.left().Value() >> m.right().Value());
795 if (m.left().IsWord32Shl()) {
796 Int32BinopMatcher mleft(m.left().node());
797 if (mleft.left().IsComparison()) {
798 if (m.right().Is(31) && mleft.right().Is(31)) {
799 // Comparison << 31 >> 31 => 0 - Comparison
800 node->set_op(machine()->Int32Sub());
801 node->ReplaceInput(0, Int32Constant(0));
802 node->ReplaceInput(1, mleft.left().node());
803 Reduction const reduction = ReduceInt32Sub(node);
804 return reduction.Changed() ? reduction : Changed(node);
806 } else if (mleft.left().IsLoad()) {
807 LoadRepresentation const rep =
808 OpParameter<LoadRepresentation>(mleft.left().node());
809 if (m.right().Is(24) && mleft.right().Is(24) && rep == kMachInt8) {
810 // Load[kMachInt8] << 24 >> 24 => Load[kMachInt8]
811 return Replace(mleft.left().node());
813 if (m.right().Is(16) && mleft.right().Is(16) && rep == kMachInt16) {
814 // Load[kMachInt16] << 16 >> 16 => Load[kMachInt8]
815 return Replace(mleft.left().node());
819 return ReduceWord32Shifts(node);
823 Reduction MachineOperatorReducer::ReduceWord32And(Node* node) {
824 DCHECK_EQ(IrOpcode::kWord32And, node->opcode());
825 Int32BinopMatcher m(node);
826 if (m.right().Is(0)) return Replace(m.right().node()); // x & 0 => 0
827 if (m.right().Is(-1)) return Replace(m.left().node()); // x & -1 => x
828 if (m.left().IsComparison() && m.right().Is(1)) { // CMP & 1 => CMP
829 return Replace(m.left().node());
831 if (m.IsFoldable()) { // K & K => K
832 return ReplaceInt32(m.left().Value() & m.right().Value());
834 if (m.LeftEqualsRight()) return Replace(m.left().node()); // x & x => x
835 if (m.left().IsWord32And() && m.right().HasValue()) {
836 Int32BinopMatcher mleft(m.left().node());
837 if (mleft.right().HasValue()) { // (x & K) & K => x & K
838 node->ReplaceInput(0, mleft.left().node());
840 1, Int32Constant(m.right().Value() & mleft.right().Value()));
841 Reduction const reduction = ReduceWord32And(node);
842 return reduction.Changed() ? reduction : Changed(node);
845 if (m.right().IsNegativePowerOf2()) {
846 int32_t const mask = m.right().Value();
847 if (m.left().IsWord32Shl()) {
848 Uint32BinopMatcher mleft(m.left().node());
849 if (mleft.right().HasValue() &&
850 mleft.right().Value() >= base::bits::CountTrailingZeros32(mask)) {
851 // (x << L) & (-1 << K) => x << L iff K >= L
852 return Replace(mleft.node());
854 } else if (m.left().IsInt32Add()) {
855 Int32BinopMatcher mleft(m.left().node());
856 if (mleft.right().HasValue() &&
857 (mleft.right().Value() & mask) == mleft.right().Value()) {
858 // (x + (K << L)) & (-1 << L) => (x & (-1 << L)) + (K << L)
859 node->set_op(machine()->Int32Add());
860 node->ReplaceInput(0, Word32And(mleft.left().node(), m.right().node()));
861 node->ReplaceInput(1, mleft.right().node());
862 Reduction const reduction = ReduceInt32Add(node);
863 return reduction.Changed() ? reduction : Changed(node);
865 if (mleft.left().IsInt32Mul()) {
866 Int32BinopMatcher mleftleft(mleft.left().node());
867 if (mleftleft.right().IsMultipleOf(-mask)) {
868 // (y * (K << L) + x) & (-1 << L) => (x & (-1 << L)) + y * (K << L)
869 node->set_op(machine()->Int32Add());
870 node->ReplaceInput(0,
871 Word32And(mleft.right().node(), m.right().node()));
872 node->ReplaceInput(1, mleftleft.node());
873 Reduction const reduction = ReduceInt32Add(node);
874 return reduction.Changed() ? reduction : Changed(node);
877 if (mleft.right().IsInt32Mul()) {
878 Int32BinopMatcher mleftright(mleft.right().node());
879 if (mleftright.right().IsMultipleOf(-mask)) {
880 // (x + y * (K << L)) & (-1 << L) => (x & (-1 << L)) + y * (K << L)
881 node->set_op(machine()->Int32Add());
882 node->ReplaceInput(0,
883 Word32And(mleft.left().node(), m.right().node()));
884 node->ReplaceInput(1, mleftright.node());
885 Reduction const reduction = ReduceInt32Add(node);
886 return reduction.Changed() ? reduction : Changed(node);
889 if (mleft.left().IsWord32Shl()) {
890 Int32BinopMatcher mleftleft(mleft.left().node());
891 if (mleftleft.right().Is(base::bits::CountTrailingZeros32(mask))) {
892 // (y << L + x) & (-1 << L) => (x & (-1 << L)) + y << L
893 node->set_op(machine()->Int32Add());
894 node->ReplaceInput(0,
895 Word32And(mleft.right().node(), m.right().node()));
896 node->ReplaceInput(1, mleftleft.node());
897 Reduction const reduction = ReduceInt32Add(node);
898 return reduction.Changed() ? reduction : Changed(node);
901 if (mleft.right().IsWord32Shl()) {
902 Int32BinopMatcher mleftright(mleft.right().node());
903 if (mleftright.right().Is(base::bits::CountTrailingZeros32(mask))) {
904 // (x + y << L) & (-1 << L) => (x & (-1 << L)) + y << L
905 node->set_op(machine()->Int32Add());
906 node->ReplaceInput(0,
907 Word32And(mleft.left().node(), m.right().node()));
908 node->ReplaceInput(1, mleftright.node());
909 Reduction const reduction = ReduceInt32Add(node);
910 return reduction.Changed() ? reduction : Changed(node);
913 } else if (m.left().IsInt32Mul()) {
914 Int32BinopMatcher mleft(m.left().node());
915 if (mleft.right().IsMultipleOf(-mask)) {
916 // (x * (K << L)) & (-1 << L) => x * (K << L)
917 return Replace(mleft.node());
925 Reduction MachineOperatorReducer::ReduceWord32Or(Node* node) {
926 DCHECK_EQ(IrOpcode::kWord32Or, node->opcode());
927 Int32BinopMatcher m(node);
928 if (m.right().Is(0)) return Replace(m.left().node()); // x | 0 => x
929 if (m.right().Is(-1)) return Replace(m.right().node()); // x | -1 => -1
930 if (m.IsFoldable()) { // K | K => K
931 return ReplaceInt32(m.left().Value() | m.right().Value());
933 if (m.LeftEqualsRight()) return Replace(m.left().node()); // x | x => x
937 // Recognize rotation, we are matching either:
938 // * x << y | x >>> (32 - y) => x ror (32 - y), i.e x rol y
939 // * x << (32 - y) | x >>> y => x ror y
940 // as well as their commuted form.
941 if (m.left().IsWord32Shl() && m.right().IsWord32Shr()) {
942 shl = m.left().node();
943 shr = m.right().node();
944 } else if (m.left().IsWord32Shr() && m.right().IsWord32Shl()) {
945 shl = m.right().node();
946 shr = m.left().node();
951 Int32BinopMatcher mshl(shl);
952 Int32BinopMatcher mshr(shr);
953 if (mshl.left().node() != mshr.left().node()) return NoChange();
955 if (mshl.right().HasValue() && mshr.right().HasValue()) {
956 // Case where y is a constant.
957 if (mshl.right().Value() + mshr.right().Value() != 32) return NoChange();
961 if (mshl.right().IsInt32Sub()) {
962 sub = mshl.right().node();
963 y = mshr.right().node();
964 } else if (mshr.right().IsInt32Sub()) {
965 sub = mshr.right().node();
966 y = mshl.right().node();
971 Int32BinopMatcher msub(sub);
972 if (!msub.left().Is(32) || msub.right().node() != y) return NoChange();
975 node->set_op(machine()->Word32Ror());
976 node->ReplaceInput(0, mshl.left().node());
977 node->ReplaceInput(1, mshr.right().node());
978 return Changed(node);
982 Reduction MachineOperatorReducer::ReduceFloat64InsertLowWord32(Node* node) {
983 DCHECK_EQ(IrOpcode::kFloat64InsertLowWord32, node->opcode());
984 Float64Matcher mlhs(node->InputAt(0));
985 Uint32Matcher mrhs(node->InputAt(1));
986 if (mlhs.HasValue() && mrhs.HasValue()) {
987 return ReplaceFloat64(bit_cast<double>(
988 (bit_cast<uint64_t>(mlhs.Value()) & V8_UINT64_C(0xFFFFFFFF00000000)) |
995 Reduction MachineOperatorReducer::ReduceFloat64InsertHighWord32(Node* node) {
996 DCHECK_EQ(IrOpcode::kFloat64InsertHighWord32, node->opcode());
997 Float64Matcher mlhs(node->InputAt(0));
998 Uint32Matcher mrhs(node->InputAt(1));
999 if (mlhs.HasValue() && mrhs.HasValue()) {
1000 return ReplaceFloat64(bit_cast<double>(
1001 (bit_cast<uint64_t>(mlhs.Value()) & V8_UINT64_C(0xFFFFFFFF)) |
1002 (static_cast<uint64_t>(mrhs.Value()) << 32)));
1008 CommonOperatorBuilder* MachineOperatorReducer::common() const {
1009 return jsgraph()->common();
1013 MachineOperatorBuilder* MachineOperatorReducer::machine() const {
1014 return jsgraph()->machine();
1018 Graph* MachineOperatorReducer::graph() const { return jsgraph()->graph(); }
1020 } // namespace compiler
1021 } // namespace internal