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.
4
5 #include "src/compiler/machine-operator-reducer.h"
6
7 #include "src/base/bits.h"
8 #include "src/base/division-by-constant.h"
9 #include "src/base/ieee754.h"
10 #include "src/compiler/diamond.h"
11 #include "src/compiler/graph.h"
12 #include "src/compiler/machine-graph.h"
13 #include "src/compiler/node-matchers.h"
14 #include "src/compiler/node-properties.h"
15 #include "src/conversions-inl.h"
16
17 namespace v8 {
18 namespace internal {
19 namespace compiler {
20
MachineOperatorReducer(MachineGraph * mcgraph,bool allow_signalling_nan)21 MachineOperatorReducer::MachineOperatorReducer(MachineGraph* mcgraph,
22 bool allow_signalling_nan)
23 : mcgraph_(mcgraph), allow_signalling_nan_(allow_signalling_nan) {}
24
~MachineOperatorReducer()25 MachineOperatorReducer::~MachineOperatorReducer() {}
26
27
Float32Constant(volatile float value)28 Node* MachineOperatorReducer::Float32Constant(volatile float value) {
29 return graph()->NewNode(common()->Float32Constant(value));
30 }
31
32
Float64Constant(volatile double value)33 Node* MachineOperatorReducer::Float64Constant(volatile double value) {
34 return mcgraph()->Float64Constant(value);
35 }
36
37
Int32Constant(int32_t value)38 Node* MachineOperatorReducer::Int32Constant(int32_t value) {
39 return mcgraph()->Int32Constant(value);
40 }
41
42
Int64Constant(int64_t value)43 Node* MachineOperatorReducer::Int64Constant(int64_t value) {
44 return graph()->NewNode(common()->Int64Constant(value));
45 }
46
Float64Mul(Node * lhs,Node * rhs)47 Node* MachineOperatorReducer::Float64Mul(Node* lhs, Node* rhs) {
48 return graph()->NewNode(machine()->Float64Mul(), lhs, rhs);
49 }
50
Float64PowHalf(Node * value)51 Node* MachineOperatorReducer::Float64PowHalf(Node* value) {
52 value =
53 graph()->NewNode(machine()->Float64Add(), Float64Constant(0.0), value);
54 Diamond d(graph(), common(),
55 graph()->NewNode(machine()->Float64LessThanOrEqual(), value,
56 Float64Constant(-V8_INFINITY)),
57 BranchHint::kFalse);
58 return d.Phi(MachineRepresentation::kFloat64, Float64Constant(V8_INFINITY),
59 graph()->NewNode(machine()->Float64Sqrt(), value));
60 }
61
Word32And(Node * lhs,Node * rhs)62 Node* MachineOperatorReducer::Word32And(Node* lhs, Node* rhs) {
63 Node* const node = graph()->NewNode(machine()->Word32And(), lhs, rhs);
64 Reduction const reduction = ReduceWord32And(node);
65 return reduction.Changed() ? reduction.replacement() : node;
66 }
67
68
Word32Sar(Node * lhs,uint32_t rhs)69 Node* MachineOperatorReducer::Word32Sar(Node* lhs, uint32_t rhs) {
70 if (rhs == 0) return lhs;
71 return graph()->NewNode(machine()->Word32Sar(), lhs, Uint32Constant(rhs));
72 }
73
74
Word32Shr(Node * lhs,uint32_t rhs)75 Node* MachineOperatorReducer::Word32Shr(Node* lhs, uint32_t rhs) {
76 if (rhs == 0) return lhs;
77 return graph()->NewNode(machine()->Word32Shr(), lhs, Uint32Constant(rhs));
78 }
79
80
Word32Equal(Node * lhs,Node * rhs)81 Node* MachineOperatorReducer::Word32Equal(Node* lhs, Node* rhs) {
82 return graph()->NewNode(machine()->Word32Equal(), lhs, rhs);
83 }
84
85
Int32Add(Node * lhs,Node * rhs)86 Node* MachineOperatorReducer::Int32Add(Node* lhs, Node* rhs) {
87 Node* const node = graph()->NewNode(machine()->Int32Add(), lhs, rhs);
88 Reduction const reduction = ReduceInt32Add(node);
89 return reduction.Changed() ? reduction.replacement() : node;
90 }
91
92
Int32Sub(Node * lhs,Node * rhs)93 Node* MachineOperatorReducer::Int32Sub(Node* lhs, Node* rhs) {
94 Node* const node = graph()->NewNode(machine()->Int32Sub(), lhs, rhs);
95 Reduction const reduction = ReduceInt32Sub(node);
96 return reduction.Changed() ? reduction.replacement() : node;
97 }
98
99
Int32Mul(Node * lhs,Node * rhs)100 Node* MachineOperatorReducer::Int32Mul(Node* lhs, Node* rhs) {
101 return graph()->NewNode(machine()->Int32Mul(), lhs, rhs);
102 }
103
104
Int32Div(Node * dividend,int32_t divisor)105 Node* MachineOperatorReducer::Int32Div(Node* dividend, int32_t divisor) {
106 DCHECK_NE(0, divisor);
107 DCHECK_NE(std::numeric_limits<int32_t>::min(), divisor);
108 base::MagicNumbersForDivision<uint32_t> const mag =
109 base::SignedDivisionByConstant(bit_cast<uint32_t>(divisor));
110 Node* quotient = graph()->NewNode(machine()->Int32MulHigh(), dividend,
111 Uint32Constant(mag.multiplier));
112 if (divisor > 0 && bit_cast<int32_t>(mag.multiplier) < 0) {
113 quotient = Int32Add(quotient, dividend);
114 } else if (divisor < 0 && bit_cast<int32_t>(mag.multiplier) > 0) {
115 quotient = Int32Sub(quotient, dividend);
116 }
117 return Int32Add(Word32Sar(quotient, mag.shift), Word32Shr(dividend, 31));
118 }
119
120
Uint32Div(Node * dividend,uint32_t divisor)121 Node* MachineOperatorReducer::Uint32Div(Node* dividend, uint32_t divisor) {
122 DCHECK_LT(0u, divisor);
123 // If the divisor is even, we can avoid using the expensive fixup by shifting
124 // the dividend upfront.
125 unsigned const shift = base::bits::CountTrailingZeros(divisor);
126 dividend = Word32Shr(dividend, shift);
127 divisor >>= shift;
128 // Compute the magic number for the (shifted) divisor.
129 base::MagicNumbersForDivision<uint32_t> const mag =
130 base::UnsignedDivisionByConstant(divisor, shift);
131 Node* quotient = graph()->NewNode(machine()->Uint32MulHigh(), dividend,
132 Uint32Constant(mag.multiplier));
133 if (mag.add) {
134 DCHECK_LE(1u, mag.shift);
135 quotient = Word32Shr(
136 Int32Add(Word32Shr(Int32Sub(dividend, quotient), 1), quotient),
137 mag.shift - 1);
138 } else {
139 quotient = Word32Shr(quotient, mag.shift);
140 }
141 return quotient;
142 }
143
144
145 // Perform constant folding and strength reduction on machine operators.
Reduce(Node * node)146 Reduction MachineOperatorReducer::Reduce(Node* node) {
147 switch (node->opcode()) {
148 case IrOpcode::kProjection:
149 return ReduceProjection(ProjectionIndexOf(node->op()), node->InputAt(0));
150 case IrOpcode::kWord32And:
151 return ReduceWord32And(node);
152 case IrOpcode::kWord32Or:
153 return ReduceWord32Or(node);
154 case IrOpcode::kWord32Xor:
155 return ReduceWord32Xor(node);
156 case IrOpcode::kWord32Shl:
157 return ReduceWord32Shl(node);
158 case IrOpcode::kWord64Shl:
159 return ReduceWord64Shl(node);
160 case IrOpcode::kWord32Shr:
161 return ReduceWord32Shr(node);
162 case IrOpcode::kWord64Shr:
163 return ReduceWord64Shr(node);
164 case IrOpcode::kWord32Sar:
165 return ReduceWord32Sar(node);
166 case IrOpcode::kWord64Sar:
167 return ReduceWord64Sar(node);
168 case IrOpcode::kWord32Ror: {
169 Int32BinopMatcher m(node);
170 if (m.right().Is(0)) return Replace(m.left().node()); // x ror 0 => x
171 if (m.IsFoldable()) { // K ror K => K
172 return ReplaceInt32(
173 base::bits::RotateRight32(m.left().Value(), m.right().Value()));
174 }
175 break;
176 }
177 case IrOpcode::kWord32Equal: {
178 Int32BinopMatcher m(node);
179 if (m.IsFoldable()) { // K == K => K
180 return ReplaceBool(m.left().Value() == m.right().Value());
181 }
182 if (m.left().IsInt32Sub() && m.right().Is(0)) { // x - y == 0 => x == y
183 Int32BinopMatcher msub(m.left().node());
184 node->ReplaceInput(0, msub.left().node());
185 node->ReplaceInput(1, msub.right().node());
186 return Changed(node);
187 }
188 // TODO(turbofan): fold HeapConstant, ExternalReference, pointer compares
189 if (m.LeftEqualsRight()) return ReplaceBool(true); // x == x => true
190 break;
191 }
192 case IrOpcode::kWord64Equal: {
193 Int64BinopMatcher m(node);
194 if (m.IsFoldable()) { // K == K => K
195 return ReplaceBool(m.left().Value() == m.right().Value());
196 }
197 if (m.left().IsInt64Sub() && m.right().Is(0)) { // x - y == 0 => x == y
198 Int64BinopMatcher msub(m.left().node());
199 node->ReplaceInput(0, msub.left().node());
200 node->ReplaceInput(1, msub.right().node());
201 return Changed(node);
202 }
203 // TODO(turbofan): fold HeapConstant, ExternalReference, pointer compares
204 if (m.LeftEqualsRight()) return ReplaceBool(true); // x == x => true
205 break;
206 }
207 case IrOpcode::kInt32Add:
208 return ReduceInt32Add(node);
209 case IrOpcode::kInt64Add:
210 return ReduceInt64Add(node);
211 case IrOpcode::kInt32Sub:
212 return ReduceInt32Sub(node);
213 case IrOpcode::kInt64Sub:
214 return ReduceInt64Sub(node);
215 case IrOpcode::kInt32Mul: {
216 Int32BinopMatcher m(node);
217 if (m.right().Is(0)) return Replace(m.right().node()); // x * 0 => 0
218 if (m.right().Is(1)) return Replace(m.left().node()); // x * 1 => x
219 if (m.IsFoldable()) { // K * K => K
220 return ReplaceInt32(m.left().Value() * m.right().Value());
221 }
222 if (m.right().Is(-1)) { // x * -1 => 0 - x
223 node->ReplaceInput(0, Int32Constant(0));
224 node->ReplaceInput(1, m.left().node());
225 NodeProperties::ChangeOp(node, machine()->Int32Sub());
226 return Changed(node);
227 }
228 if (m.right().IsPowerOf2()) { // x * 2^n => x << n
229 node->ReplaceInput(1, Int32Constant(WhichPowerOf2(m.right().Value())));
230 NodeProperties::ChangeOp(node, machine()->Word32Shl());
231 Reduction reduction = ReduceWord32Shl(node);
232 return reduction.Changed() ? reduction : Changed(node);
233 }
234 break;
235 }
236 case IrOpcode::kInt32MulWithOverflow: {
237 Int32BinopMatcher m(node);
238 if (m.right().Is(2)) {
239 node->ReplaceInput(1, m.left().node());
240 NodeProperties::ChangeOp(node, machine()->Int32AddWithOverflow());
241 return Changed(node);
242 }
243 if (m.right().Is(-1)) {
244 node->ReplaceInput(0, Int32Constant(0));
245 node->ReplaceInput(1, m.left().node());
246 NodeProperties::ChangeOp(node, machine()->Int32SubWithOverflow());
247 return Changed(node);
248 }
249 break;
250 }
251 case IrOpcode::kInt32Div:
252 return ReduceInt32Div(node);
253 case IrOpcode::kUint32Div:
254 return ReduceUint32Div(node);
255 case IrOpcode::kInt32Mod:
256 return ReduceInt32Mod(node);
257 case IrOpcode::kUint32Mod:
258 return ReduceUint32Mod(node);
259 case IrOpcode::kInt32LessThan: {
260 Int32BinopMatcher m(node);
261 if (m.IsFoldable()) { // K < K => K
262 return ReplaceBool(m.left().Value() < m.right().Value());
263 }
264 if (m.LeftEqualsRight()) return ReplaceBool(false); // x < x => false
265 if (m.left().IsWord32Or() && m.right().Is(0)) {
266 // (x | K) < 0 => true or (K | x) < 0 => true iff K < 0
267 Int32BinopMatcher mleftmatcher(m.left().node());
268 if (mleftmatcher.left().IsNegative() ||
269 mleftmatcher.right().IsNegative()) {
270 return ReplaceBool(true);
271 }
272 }
273 break;
274 }
275 case IrOpcode::kInt32LessThanOrEqual: {
276 Int32BinopMatcher m(node);
277 if (m.IsFoldable()) { // K <= K => K
278 return ReplaceBool(m.left().Value() <= m.right().Value());
279 }
280 if (m.LeftEqualsRight()) return ReplaceBool(true); // x <= x => true
281 break;
282 }
283 case IrOpcode::kUint32LessThan: {
284 Uint32BinopMatcher m(node);
285 if (m.left().Is(kMaxUInt32)) return ReplaceBool(false); // M < x => false
286 if (m.right().Is(0)) return ReplaceBool(false); // x < 0 => false
287 if (m.IsFoldable()) { // K < K => K
288 return ReplaceBool(m.left().Value() < m.right().Value());
289 }
290 if (m.LeftEqualsRight()) return ReplaceBool(false); // x < x => false
291 if (m.left().IsWord32Sar() && m.right().HasValue()) {
292 Int32BinopMatcher mleft(m.left().node());
293 if (mleft.right().HasValue()) {
294 // (x >> K) < C => x < (C << K)
295 // when C < (M >> K)
296 const uint32_t c = m.right().Value();
297 const uint32_t k = mleft.right().Value() & 0x1F;
298 if (c < static_cast<uint32_t>(kMaxInt >> k)) {
299 node->ReplaceInput(0, mleft.left().node());
300 node->ReplaceInput(1, Uint32Constant(c << k));
301 return Changed(node);
302 }
303 // TODO(turbofan): else the comparison is always true.
304 }
305 }
306 break;
307 }
308 case IrOpcode::kUint32LessThanOrEqual: {
309 Uint32BinopMatcher m(node);
310 if (m.left().Is(0)) return ReplaceBool(true); // 0 <= x => true
311 if (m.right().Is(kMaxUInt32)) return ReplaceBool(true); // x <= M => true
312 if (m.IsFoldable()) { // K <= K => K
313 return ReplaceBool(m.left().Value() <= m.right().Value());
314 }
315 if (m.LeftEqualsRight()) return ReplaceBool(true); // x <= x => true
316 break;
317 }
318 case IrOpcode::kFloat32Sub: {
319 Float32BinopMatcher m(node);
320 if (allow_signalling_nan_ && m.right().Is(0) &&
321 (copysign(1.0, m.right().Value()) > 0)) {
322 return Replace(m.left().node()); // x - 0 => x
323 }
324 if (m.right().IsNaN()) { // x - NaN => NaN
325 // Do some calculation to make a signalling NaN quiet.
326 return ReplaceFloat32(m.right().Value() - m.right().Value());
327 }
328 if (m.left().IsNaN()) { // NaN - x => NaN
329 // Do some calculation to make a signalling NaN quiet.
330 return ReplaceFloat32(m.left().Value() - m.left().Value());
331 }
332 if (m.IsFoldable()) { // L - R => (L - R)
333 return ReplaceFloat32(m.left().Value() - m.right().Value());
334 }
335 if (allow_signalling_nan_ && m.left().IsMinusZero()) {
336 // -0.0 - round_down(-0.0 - R) => round_up(R)
337 if (machine()->Float32RoundUp().IsSupported() &&
338 m.right().IsFloat32RoundDown()) {
339 if (m.right().InputAt(0)->opcode() == IrOpcode::kFloat32Sub) {
340 Float32BinopMatcher mright0(m.right().InputAt(0));
341 if (mright0.left().IsMinusZero()) {
342 return Replace(graph()->NewNode(machine()->Float32RoundUp().op(),
343 mright0.right().node()));
344 }
345 }
346 }
347 // -0.0 - R => -R
348 node->RemoveInput(0);
349 NodeProperties::ChangeOp(node, machine()->Float32Neg());
350 return Changed(node);
351 }
352 break;
353 }
354 case IrOpcode::kFloat64Add: {
355 Float64BinopMatcher m(node);
356 if (m.IsFoldable()) { // K + K => K
357 return ReplaceFloat64(m.left().Value() + m.right().Value());
358 }
359 break;
360 }
361 case IrOpcode::kFloat64Sub: {
362 Float64BinopMatcher m(node);
363 if (allow_signalling_nan_ && m.right().Is(0) &&
364 (Double(m.right().Value()).Sign() > 0)) {
365 return Replace(m.left().node()); // x - 0 => x
366 }
367 if (m.right().IsNaN()) { // x - NaN => NaN
368 // Do some calculation to make a signalling NaN quiet.
369 return ReplaceFloat64(m.right().Value() - m.right().Value());
370 }
371 if (m.left().IsNaN()) { // NaN - x => NaN
372 // Do some calculation to make a signalling NaN quiet.
373 return ReplaceFloat64(m.left().Value() - m.left().Value());
374 }
375 if (m.IsFoldable()) { // L - R => (L - R)
376 return ReplaceFloat64(m.left().Value() - m.right().Value());
377 }
378 if (allow_signalling_nan_ && m.left().IsMinusZero()) {
379 // -0.0 - round_down(-0.0 - R) => round_up(R)
380 if (machine()->Float64RoundUp().IsSupported() &&
381 m.right().IsFloat64RoundDown()) {
382 if (m.right().InputAt(0)->opcode() == IrOpcode::kFloat64Sub) {
383 Float64BinopMatcher mright0(m.right().InputAt(0));
384 if (mright0.left().IsMinusZero()) {
385 return Replace(graph()->NewNode(machine()->Float64RoundUp().op(),
386 mright0.right().node()));
387 }
388 }
389 }
390 // -0.0 - R => -R
391 node->RemoveInput(0);
392 NodeProperties::ChangeOp(node, machine()->Float64Neg());
393 return Changed(node);
394 }
395 break;
396 }
397 case IrOpcode::kFloat64Mul: {
398 Float64BinopMatcher m(node);
399 if (allow_signalling_nan_ && m.right().Is(1))
400 return Replace(m.left().node()); // x * 1.0 => x
401 if (m.right().Is(-1)) { // x * -1.0 => -0.0 - x
402 node->ReplaceInput(0, Float64Constant(-0.0));
403 node->ReplaceInput(1, m.left().node());
404 NodeProperties::ChangeOp(node, machine()->Float64Sub());
405 return Changed(node);
406 }
407 if (m.right().IsNaN()) { // x * NaN => NaN
408 // Do some calculation to make a signalling NaN quiet.
409 return ReplaceFloat64(m.right().Value() - m.right().Value());
410 }
411 if (m.IsFoldable()) { // K * K => K
412 return ReplaceFloat64(m.left().Value() * m.right().Value());
413 }
414 if (m.right().Is(2)) { // x * 2.0 => x + x
415 node->ReplaceInput(1, m.left().node());
416 NodeProperties::ChangeOp(node, machine()->Float64Add());
417 return Changed(node);
418 }
419 break;
420 }
421 case IrOpcode::kFloat64Div: {
422 Float64BinopMatcher m(node);
423 if (allow_signalling_nan_ && m.right().Is(1))
424 return Replace(m.left().node()); // x / 1.0 => x
425 // TODO(ahaas): We could do x / 1.0 = x if we knew that x is not an sNaN.
426 if (m.right().IsNaN()) { // x / NaN => NaN
427 // Do some calculation to make a signalling NaN quiet.
428 return ReplaceFloat64(m.right().Value() - m.right().Value());
429 }
430 if (m.left().IsNaN()) { // NaN / x => NaN
431 // Do some calculation to make a signalling NaN quiet.
432 return ReplaceFloat64(m.left().Value() - m.left().Value());
433 }
434 if (m.IsFoldable()) { // K / K => K
435 return ReplaceFloat64(m.left().Value() / m.right().Value());
436 }
437 if (allow_signalling_nan_ && m.right().Is(-1)) { // x / -1.0 => -x
438 node->RemoveInput(1);
439 NodeProperties::ChangeOp(node, machine()->Float64Neg());
440 return Changed(node);
441 }
442 if (m.right().IsNormal() && m.right().IsPositiveOrNegativePowerOf2()) {
443 // All reciprocals of non-denormal powers of two can be represented
444 // exactly, so division by power of two can be reduced to
445 // multiplication by reciprocal, with the same result.
446 node->ReplaceInput(1, Float64Constant(1.0 / m.right().Value()));
447 NodeProperties::ChangeOp(node, machine()->Float64Mul());
448 return Changed(node);
449 }
450 break;
451 }
452 case IrOpcode::kFloat64Mod: {
453 Float64BinopMatcher m(node);
454 if (m.right().Is(0)) { // x % 0 => NaN
455 return ReplaceFloat64(std::numeric_limits<double>::quiet_NaN());
456 }
457 if (m.right().IsNaN()) { // x % NaN => NaN
458 return Replace(m.right().node());
459 }
460 if (m.left().IsNaN()) { // NaN % x => NaN
461 return Replace(m.left().node());
462 }
463 if (m.IsFoldable()) { // K % K => K
464 return ReplaceFloat64(Modulo(m.left().Value(), m.right().Value()));
465 }
466 break;
467 }
468 case IrOpcode::kFloat64Acos: {
469 Float64Matcher m(node->InputAt(0));
470 if (m.HasValue()) return ReplaceFloat64(base::ieee754::acos(m.Value()));
471 break;
472 }
473 case IrOpcode::kFloat64Acosh: {
474 Float64Matcher m(node->InputAt(0));
475 if (m.HasValue()) return ReplaceFloat64(base::ieee754::acosh(m.Value()));
476 break;
477 }
478 case IrOpcode::kFloat64Asin: {
479 Float64Matcher m(node->InputAt(0));
480 if (m.HasValue()) return ReplaceFloat64(base::ieee754::asin(m.Value()));
481 break;
482 }
483 case IrOpcode::kFloat64Asinh: {
484 Float64Matcher m(node->InputAt(0));
485 if (m.HasValue()) return ReplaceFloat64(base::ieee754::asinh(m.Value()));
486 break;
487 }
488 case IrOpcode::kFloat64Atan: {
489 Float64Matcher m(node->InputAt(0));
490 if (m.HasValue()) return ReplaceFloat64(base::ieee754::atan(m.Value()));
491 break;
492 }
493 case IrOpcode::kFloat64Atanh: {
494 Float64Matcher m(node->InputAt(0));
495 if (m.HasValue()) return ReplaceFloat64(base::ieee754::atanh(m.Value()));
496 break;
497 }
498 case IrOpcode::kFloat64Atan2: {
499 Float64BinopMatcher m(node);
500 if (m.right().IsNaN()) {
501 return Replace(m.right().node());
502 }
503 if (m.left().IsNaN()) {
504 return Replace(m.left().node());
505 }
506 if (m.IsFoldable()) {
507 return ReplaceFloat64(
508 base::ieee754::atan2(m.left().Value(), m.right().Value()));
509 }
510 break;
511 }
512 case IrOpcode::kFloat64Cbrt: {
513 Float64Matcher m(node->InputAt(0));
514 if (m.HasValue()) return ReplaceFloat64(base::ieee754::cbrt(m.Value()));
515 break;
516 }
517 case IrOpcode::kFloat64Cos: {
518 Float64Matcher m(node->InputAt(0));
519 if (m.HasValue()) return ReplaceFloat64(base::ieee754::cos(m.Value()));
520 break;
521 }
522 case IrOpcode::kFloat64Cosh: {
523 Float64Matcher m(node->InputAt(0));
524 if (m.HasValue()) return ReplaceFloat64(base::ieee754::cosh(m.Value()));
525 break;
526 }
527 case IrOpcode::kFloat64Exp: {
528 Float64Matcher m(node->InputAt(0));
529 if (m.HasValue()) return ReplaceFloat64(base::ieee754::exp(m.Value()));
530 break;
531 }
532 case IrOpcode::kFloat64Expm1: {
533 Float64Matcher m(node->InputAt(0));
534 if (m.HasValue()) return ReplaceFloat64(base::ieee754::expm1(m.Value()));
535 break;
536 }
537 case IrOpcode::kFloat64Log: {
538 Float64Matcher m(node->InputAt(0));
539 if (m.HasValue()) return ReplaceFloat64(base::ieee754::log(m.Value()));
540 break;
541 }
542 case IrOpcode::kFloat64Log1p: {
543 Float64Matcher m(node->InputAt(0));
544 if (m.HasValue()) return ReplaceFloat64(base::ieee754::log1p(m.Value()));
545 break;
546 }
547 case IrOpcode::kFloat64Log10: {
548 Float64Matcher m(node->InputAt(0));
549 if (m.HasValue()) return ReplaceFloat64(base::ieee754::log10(m.Value()));
550 break;
551 }
552 case IrOpcode::kFloat64Log2: {
553 Float64Matcher m(node->InputAt(0));
554 if (m.HasValue()) return ReplaceFloat64(base::ieee754::log2(m.Value()));
555 break;
556 }
557 case IrOpcode::kFloat64Pow: {
558 Float64BinopMatcher m(node);
559 if (m.IsFoldable()) {
560 return ReplaceFloat64(Pow(m.left().Value(), m.right().Value()));
561 } else if (m.right().Is(0.0)) { // x ** +-0.0 => 1.0
562 return ReplaceFloat64(1.0);
563 } else if (m.right().Is(-2.0)) { // x ** -2.0 => 1 / (x * x)
564 node->ReplaceInput(0, Float64Constant(1.0));
565 node->ReplaceInput(1, Float64Mul(m.left().node(), m.left().node()));
566 NodeProperties::ChangeOp(node, machine()->Float64Div());
567 return Changed(node);
568 } else if (m.right().Is(2.0)) { // x ** 2.0 => x * x
569 node->ReplaceInput(1, m.left().node());
570 NodeProperties::ChangeOp(node, machine()->Float64Mul());
571 return Changed(node);
572 } else if (m.right().Is(-0.5)) {
573 // x ** 0.5 => 1 / (if x <= -Infinity then Infinity else sqrt(0.0 + x))
574 node->ReplaceInput(0, Float64Constant(1.0));
575 node->ReplaceInput(1, Float64PowHalf(m.left().node()));
576 NodeProperties::ChangeOp(node, machine()->Float64Div());
577 return Changed(node);
578 } else if (m.right().Is(0.5)) {
579 // x ** 0.5 => if x <= -Infinity then Infinity else sqrt(0.0 + x)
580 return Replace(Float64PowHalf(m.left().node()));
581 }
582 break;
583 }
584 case IrOpcode::kFloat64Sin: {
585 Float64Matcher m(node->InputAt(0));
586 if (m.HasValue()) return ReplaceFloat64(base::ieee754::sin(m.Value()));
587 break;
588 }
589 case IrOpcode::kFloat64Sinh: {
590 Float64Matcher m(node->InputAt(0));
591 if (m.HasValue()) return ReplaceFloat64(base::ieee754::sinh(m.Value()));
592 break;
593 }
594 case IrOpcode::kFloat64Tan: {
595 Float64Matcher m(node->InputAt(0));
596 if (m.HasValue()) return ReplaceFloat64(base::ieee754::tan(m.Value()));
597 break;
598 }
599 case IrOpcode::kFloat64Tanh: {
600 Float64Matcher m(node->InputAt(0));
601 if (m.HasValue()) return ReplaceFloat64(base::ieee754::tanh(m.Value()));
602 break;
603 }
604 case IrOpcode::kChangeFloat32ToFloat64: {
605 Float32Matcher m(node->InputAt(0));
606 if (m.HasValue()) {
607 if (!allow_signalling_nan_ && std::isnan(m.Value())) {
608 // Do some calculation to make guarantee the value is a quiet NaN.
609 return ReplaceFloat64(m.Value() + m.Value());
610 }
611 return ReplaceFloat64(m.Value());
612 }
613 break;
614 }
615 case IrOpcode::kChangeFloat64ToInt32: {
616 Float64Matcher m(node->InputAt(0));
617 if (m.HasValue()) return ReplaceInt32(FastD2IChecked(m.Value()));
618 if (m.IsChangeInt32ToFloat64()) return Replace(m.node()->InputAt(0));
619 break;
620 }
621 case IrOpcode::kChangeFloat64ToUint32: {
622 Float64Matcher m(node->InputAt(0));
623 if (m.HasValue()) return ReplaceInt32(FastD2UI(m.Value()));
624 if (m.IsChangeUint32ToFloat64()) return Replace(m.node()->InputAt(0));
625 break;
626 }
627 case IrOpcode::kChangeInt32ToFloat64: {
628 Int32Matcher m(node->InputAt(0));
629 if (m.HasValue()) return ReplaceFloat64(FastI2D(m.Value()));
630 break;
631 }
632 case IrOpcode::kChangeInt32ToInt64: {
633 Int32Matcher m(node->InputAt(0));
634 if (m.HasValue()) return ReplaceInt64(m.Value());
635 break;
636 }
637 case IrOpcode::kChangeUint32ToFloat64: {
638 Uint32Matcher m(node->InputAt(0));
639 if (m.HasValue()) return ReplaceFloat64(FastUI2D(m.Value()));
640 break;
641 }
642 case IrOpcode::kChangeUint32ToUint64: {
643 Uint32Matcher m(node->InputAt(0));
644 if (m.HasValue()) return ReplaceInt64(static_cast<uint64_t>(m.Value()));
645 break;
646 }
647 case IrOpcode::kTruncateFloat64ToWord32: {
648 Float64Matcher m(node->InputAt(0));
649 if (m.HasValue()) return ReplaceInt32(DoubleToInt32(m.Value()));
650 if (m.IsChangeInt32ToFloat64()) return Replace(m.node()->InputAt(0));
651 return NoChange();
652 }
653 case IrOpcode::kTruncateInt64ToInt32: {
654 Int64Matcher m(node->InputAt(0));
655 if (m.HasValue()) return ReplaceInt32(static_cast<int32_t>(m.Value()));
656 if (m.IsChangeInt32ToInt64()) return Replace(m.node()->InputAt(0));
657 break;
658 }
659 case IrOpcode::kTruncateFloat64ToFloat32: {
660 Float64Matcher m(node->InputAt(0));
661 if (m.HasValue()) {
662 if (!allow_signalling_nan_ && std::isnan(m.Value())) {
663 // Do some calculation to make guarantee the value is a quiet NaN.
664 return ReplaceFloat32(DoubleToFloat32(m.Value() + m.Value()));
665 }
666 return ReplaceFloat32(DoubleToFloat32(m.Value()));
667 }
668 if (allow_signalling_nan_ && m.IsChangeFloat32ToFloat64())
669 return Replace(m.node()->InputAt(0));
670 break;
671 }
672 case IrOpcode::kRoundFloat64ToInt32: {
673 Float64Matcher m(node->InputAt(0));
674 if (m.HasValue()) {
675 return ReplaceInt32(DoubleToInt32(m.Value()));
676 }
677 if (m.IsChangeInt32ToFloat64()) return Replace(m.node()->InputAt(0));
678 break;
679 }
680 case IrOpcode::kFloat64InsertLowWord32:
681 return ReduceFloat64InsertLowWord32(node);
682 case IrOpcode::kFloat64InsertHighWord32:
683 return ReduceFloat64InsertHighWord32(node);
684 case IrOpcode::kStore:
685 case IrOpcode::kUnalignedStore:
686 return ReduceStore(node);
687 case IrOpcode::kFloat64Equal:
688 case IrOpcode::kFloat64LessThan:
689 case IrOpcode::kFloat64LessThanOrEqual:
690 return ReduceFloat64Compare(node);
691 case IrOpcode::kFloat64RoundDown:
692 return ReduceFloat64RoundDown(node);
693 default:
694 break;
695 }
696 return NoChange();
697 }
698
ReduceInt32Add(Node * node)699 Reduction MachineOperatorReducer::ReduceInt32Add(Node* node) {
700 DCHECK_EQ(IrOpcode::kInt32Add, node->opcode());
701 Int32BinopMatcher m(node);
702 if (m.right().Is(0)) return Replace(m.left().node()); // x + 0 => x
703 if (m.IsFoldable()) { // K + K => K
704 return ReplaceUint32(bit_cast<uint32_t>(m.left().Value()) +
705 bit_cast<uint32_t>(m.right().Value()));
706 }
707 if (m.left().IsInt32Sub()) {
708 Int32BinopMatcher mleft(m.left().node());
709 if (mleft.left().Is(0)) { // (0 - x) + y => y - x
710 node->ReplaceInput(0, m.right().node());
711 node->ReplaceInput(1, mleft.right().node());
712 NodeProperties::ChangeOp(node, machine()->Int32Sub());
713 Reduction const reduction = ReduceInt32Sub(node);
714 return reduction.Changed() ? reduction : Changed(node);
715 }
716 }
717 if (m.right().IsInt32Sub()) {
718 Int32BinopMatcher mright(m.right().node());
719 if (mright.left().Is(0)) { // y + (0 - x) => y - x
720 node->ReplaceInput(1, mright.right().node());
721 NodeProperties::ChangeOp(node, machine()->Int32Sub());
722 Reduction const reduction = ReduceInt32Sub(node);
723 return reduction.Changed() ? reduction : Changed(node);
724 }
725 }
726 return NoChange();
727 }
728
ReduceInt64Add(Node * node)729 Reduction MachineOperatorReducer::ReduceInt64Add(Node* node) {
730 DCHECK_EQ(IrOpcode::kInt64Add, node->opcode());
731 Int64BinopMatcher m(node);
732 if (m.right().Is(0)) return Replace(m.left().node()); // x + 0 => 0
733 if (m.IsFoldable()) {
734 return Replace(Uint64Constant(bit_cast<uint64_t>(m.left().Value()) +
735 bit_cast<uint64_t>(m.right().Value())));
736 }
737 return NoChange();
738 }
739
ReduceInt32Sub(Node * node)740 Reduction MachineOperatorReducer::ReduceInt32Sub(Node* node) {
741 DCHECK_EQ(IrOpcode::kInt32Sub, node->opcode());
742 Int32BinopMatcher m(node);
743 if (m.right().Is(0)) return Replace(m.left().node()); // x - 0 => x
744 if (m.IsFoldable()) { // K - K => K
745 return ReplaceInt32(static_cast<uint32_t>(m.left().Value()) -
746 static_cast<uint32_t>(m.right().Value()));
747 }
748 if (m.LeftEqualsRight()) return ReplaceInt32(0); // x - x => 0
749 if (m.right().HasValue()) { // x - K => x + -K
750 node->ReplaceInput(1, Int32Constant(-m.right().Value()));
751 NodeProperties::ChangeOp(node, machine()->Int32Add());
752 Reduction const reduction = ReduceInt32Add(node);
753 return reduction.Changed() ? reduction : Changed(node);
754 }
755 return NoChange();
756 }
757
ReduceInt64Sub(Node * node)758 Reduction MachineOperatorReducer::ReduceInt64Sub(Node* node) {
759 DCHECK_EQ(IrOpcode::kInt64Sub, node->opcode());
760 Int64BinopMatcher m(node);
761 if (m.right().Is(0)) return Replace(m.left().node()); // x - 0 => x
762 if (m.IsFoldable()) { // K - K => K
763 return Replace(Uint64Constant(bit_cast<uint64_t>(m.left().Value()) -
764 bit_cast<uint64_t>(m.right().Value())));
765 }
766 if (m.LeftEqualsRight()) return Replace(Int64Constant(0)); // x - x => 0
767 if (m.right().HasValue()) { // x - K => x + -K
768 node->ReplaceInput(1, Int64Constant(-m.right().Value()));
769 NodeProperties::ChangeOp(node, machine()->Int64Add());
770 Reduction const reduction = ReduceInt64Add(node);
771 return reduction.Changed() ? reduction : Changed(node);
772 }
773 return NoChange();
774 }
775
ReduceInt32Div(Node * node)776 Reduction MachineOperatorReducer::ReduceInt32Div(Node* node) {
777 Int32BinopMatcher m(node);
778 if (m.left().Is(0)) return Replace(m.left().node()); // 0 / x => 0
779 if (m.right().Is(0)) return Replace(m.right().node()); // x / 0 => 0
780 if (m.right().Is(1)) return Replace(m.left().node()); // x / 1 => x
781 if (m.IsFoldable()) { // K / K => K
782 return ReplaceInt32(
783 base::bits::SignedDiv32(m.left().Value(), m.right().Value()));
784 }
785 if (m.LeftEqualsRight()) { // x / x => x != 0
786 Node* const zero = Int32Constant(0);
787 return Replace(Word32Equal(Word32Equal(m.left().node(), zero), zero));
788 }
789 if (m.right().Is(-1)) { // x / -1 => 0 - x
790 node->ReplaceInput(0, Int32Constant(0));
791 node->ReplaceInput(1, m.left().node());
792 node->TrimInputCount(2);
793 NodeProperties::ChangeOp(node, machine()->Int32Sub());
794 return Changed(node);
795 }
796 if (m.right().HasValue()) {
797 int32_t const divisor = m.right().Value();
798 Node* const dividend = m.left().node();
799 Node* quotient = dividend;
800 if (base::bits::IsPowerOfTwo(Abs(divisor))) {
801 uint32_t const shift = WhichPowerOf2(Abs(divisor));
802 DCHECK_NE(0u, shift);
803 if (shift > 1) {
804 quotient = Word32Sar(quotient, 31);
805 }
806 quotient = Int32Add(Word32Shr(quotient, 32u - shift), dividend);
807 quotient = Word32Sar(quotient, shift);
808 } else {
809 quotient = Int32Div(quotient, Abs(divisor));
810 }
811 if (divisor < 0) {
812 node->ReplaceInput(0, Int32Constant(0));
813 node->ReplaceInput(1, quotient);
814 node->TrimInputCount(2);
815 NodeProperties::ChangeOp(node, machine()->Int32Sub());
816 return Changed(node);
817 }
818 return Replace(quotient);
819 }
820 return NoChange();
821 }
822
823
ReduceUint32Div(Node * node)824 Reduction MachineOperatorReducer::ReduceUint32Div(Node* node) {
825 Uint32BinopMatcher m(node);
826 if (m.left().Is(0)) return Replace(m.left().node()); // 0 / x => 0
827 if (m.right().Is(0)) return Replace(m.right().node()); // x / 0 => 0
828 if (m.right().Is(1)) return Replace(m.left().node()); // x / 1 => x
829 if (m.IsFoldable()) { // K / K => K
830 return ReplaceUint32(
831 base::bits::UnsignedDiv32(m.left().Value(), m.right().Value()));
832 }
833 if (m.LeftEqualsRight()) { // x / x => x != 0
834 Node* const zero = Int32Constant(0);
835 return Replace(Word32Equal(Word32Equal(m.left().node(), zero), zero));
836 }
837 if (m.right().HasValue()) {
838 Node* const dividend = m.left().node();
839 uint32_t const divisor = m.right().Value();
840 if (base::bits::IsPowerOfTwo(divisor)) { // x / 2^n => x >> n
841 node->ReplaceInput(1, Uint32Constant(WhichPowerOf2(m.right().Value())));
842 node->TrimInputCount(2);
843 NodeProperties::ChangeOp(node, machine()->Word32Shr());
844 return Changed(node);
845 } else {
846 return Replace(Uint32Div(dividend, divisor));
847 }
848 }
849 return NoChange();
850 }
851
852
ReduceInt32Mod(Node * node)853 Reduction MachineOperatorReducer::ReduceInt32Mod(Node* node) {
854 Int32BinopMatcher m(node);
855 if (m.left().Is(0)) return Replace(m.left().node()); // 0 % x => 0
856 if (m.right().Is(0)) return Replace(m.right().node()); // x % 0 => 0
857 if (m.right().Is(1)) return ReplaceInt32(0); // x % 1 => 0
858 if (m.right().Is(-1)) return ReplaceInt32(0); // x % -1 => 0
859 if (m.LeftEqualsRight()) return ReplaceInt32(0); // x % x => 0
860 if (m.IsFoldable()) { // K % K => K
861 return ReplaceInt32(
862 base::bits::SignedMod32(m.left().Value(), m.right().Value()));
863 }
864 if (m.right().HasValue()) {
865 Node* const dividend = m.left().node();
866 uint32_t const divisor = Abs(m.right().Value());
867 if (base::bits::IsPowerOfTwo(divisor)) {
868 uint32_t const mask = divisor - 1;
869 Node* const zero = Int32Constant(0);
870 Diamond d(graph(), common(),
871 graph()->NewNode(machine()->Int32LessThan(), dividend, zero),
872 BranchHint::kFalse);
873 return Replace(
874 d.Phi(MachineRepresentation::kWord32,
875 Int32Sub(zero, Word32And(Int32Sub(zero, dividend), mask)),
876 Word32And(dividend, mask)));
877 } else {
878 Node* quotient = Int32Div(dividend, divisor);
879 DCHECK_EQ(dividend, node->InputAt(0));
880 node->ReplaceInput(1, Int32Mul(quotient, Int32Constant(divisor)));
881 node->TrimInputCount(2);
882 NodeProperties::ChangeOp(node, machine()->Int32Sub());
883 }
884 return Changed(node);
885 }
886 return NoChange();
887 }
888
889
ReduceUint32Mod(Node * node)890 Reduction MachineOperatorReducer::ReduceUint32Mod(Node* node) {
891 Uint32BinopMatcher m(node);
892 if (m.left().Is(0)) return Replace(m.left().node()); // 0 % x => 0
893 if (m.right().Is(0)) return Replace(m.right().node()); // x % 0 => 0
894 if (m.right().Is(1)) return ReplaceUint32(0); // x % 1 => 0
895 if (m.LeftEqualsRight()) return ReplaceInt32(0); // x % x => 0
896 if (m.IsFoldable()) { // K % K => K
897 return ReplaceUint32(
898 base::bits::UnsignedMod32(m.left().Value(), m.right().Value()));
899 }
900 if (m.right().HasValue()) {
901 Node* const dividend = m.left().node();
902 uint32_t const divisor = m.right().Value();
903 if (base::bits::IsPowerOfTwo(divisor)) { // x % 2^n => x & 2^n-1
904 node->ReplaceInput(1, Uint32Constant(m.right().Value() - 1));
905 node->TrimInputCount(2);
906 NodeProperties::ChangeOp(node, machine()->Word32And());
907 } else {
908 Node* quotient = Uint32Div(dividend, divisor);
909 DCHECK_EQ(dividend, node->InputAt(0));
910 node->ReplaceInput(1, Int32Mul(quotient, Uint32Constant(divisor)));
911 node->TrimInputCount(2);
912 NodeProperties::ChangeOp(node, machine()->Int32Sub());
913 }
914 return Changed(node);
915 }
916 return NoChange();
917 }
918
919
ReduceStore(Node * node)920 Reduction MachineOperatorReducer::ReduceStore(Node* node) {
921 NodeMatcher nm(node);
922 MachineRepresentation rep;
923 int value_input;
924 if (nm.IsStore()) {
925 rep = StoreRepresentationOf(node->op()).representation();
926 value_input = 2;
927 } else {
928 DCHECK(nm.IsUnalignedStore());
929 rep = UnalignedStoreRepresentationOf(node->op());
930 value_input = 2;
931 }
932
933 Node* const value = node->InputAt(value_input);
934
935 switch (value->opcode()) {
936 case IrOpcode::kWord32And: {
937 Uint32BinopMatcher m(value);
938 if (m.right().HasValue() && ((rep == MachineRepresentation::kWord8 &&
939 (m.right().Value() & 0xFF) == 0xFF) ||
940 (rep == MachineRepresentation::kWord16 &&
941 (m.right().Value() & 0xFFFF) == 0xFFFF))) {
942 node->ReplaceInput(value_input, m.left().node());
943 return Changed(node);
944 }
945 break;
946 }
947 case IrOpcode::kWord32Sar: {
948 Int32BinopMatcher m(value);
949 if (m.left().IsWord32Shl() && ((rep == MachineRepresentation::kWord8 &&
950 m.right().IsInRange(1, 24)) ||
951 (rep == MachineRepresentation::kWord16 &&
952 m.right().IsInRange(1, 16)))) {
953 Int32BinopMatcher mleft(m.left().node());
954 if (mleft.right().Is(m.right().Value())) {
955 node->ReplaceInput(value_input, mleft.left().node());
956 return Changed(node);
957 }
958 }
959 break;
960 }
961 default:
962 break;
963 }
964 return NoChange();
965 }
966
967
ReduceProjection(size_t index,Node * node)968 Reduction MachineOperatorReducer::ReduceProjection(size_t index, Node* node) {
969 switch (node->opcode()) {
970 case IrOpcode::kInt32AddWithOverflow: {
971 DCHECK(index == 0 || index == 1);
972 Int32BinopMatcher m(node);
973 if (m.IsFoldable()) {
974 int32_t val;
975 bool ovf = base::bits::SignedAddOverflow32(m.left().Value(),
976 m.right().Value(), &val);
977 return ReplaceInt32(index == 0 ? val : ovf);
978 }
979 if (m.right().Is(0)) {
980 return Replace(index == 0 ? m.left().node() : m.right().node());
981 }
982 break;
983 }
984 case IrOpcode::kInt32SubWithOverflow: {
985 DCHECK(index == 0 || index == 1);
986 Int32BinopMatcher m(node);
987 if (m.IsFoldable()) {
988 int32_t val;
989 bool ovf = base::bits::SignedSubOverflow32(m.left().Value(),
990 m.right().Value(), &val);
991 return ReplaceInt32(index == 0 ? val : ovf);
992 }
993 if (m.right().Is(0)) {
994 return Replace(index == 0 ? m.left().node() : m.right().node());
995 }
996 break;
997 }
998 case IrOpcode::kInt32MulWithOverflow: {
999 DCHECK(index == 0 || index == 1);
1000 Int32BinopMatcher m(node);
1001 if (m.IsFoldable()) {
1002 int32_t val;
1003 bool ovf = base::bits::SignedMulOverflow32(m.left().Value(),
1004 m.right().Value(), &val);
1005 return ReplaceInt32(index == 0 ? val : ovf);
1006 }
1007 if (m.right().Is(0)) {
1008 return Replace(m.right().node());
1009 }
1010 if (m.right().Is(1)) {
1011 return index == 0 ? Replace(m.left().node()) : ReplaceInt32(0);
1012 }
1013 break;
1014 }
1015 default:
1016 break;
1017 }
1018 return NoChange();
1019 }
1020
1021
ReduceWord32Shifts(Node * node)1022 Reduction MachineOperatorReducer::ReduceWord32Shifts(Node* node) {
1023 DCHECK((node->opcode() == IrOpcode::kWord32Shl) ||
1024 (node->opcode() == IrOpcode::kWord32Shr) ||
1025 (node->opcode() == IrOpcode::kWord32Sar));
1026 if (machine()->Word32ShiftIsSafe()) {
1027 // Remove the explicit 'and' with 0x1F if the shift provided by the machine
1028 // instruction matches that required by JavaScript.
1029 Int32BinopMatcher m(node);
1030 if (m.right().IsWord32And()) {
1031 Int32BinopMatcher mright(m.right().node());
1032 if (mright.right().Is(0x1F)) {
1033 node->ReplaceInput(1, mright.left().node());
1034 return Changed(node);
1035 }
1036 }
1037 }
1038 return NoChange();
1039 }
1040
1041
ReduceWord32Shl(Node * node)1042 Reduction MachineOperatorReducer::ReduceWord32Shl(Node* node) {
1043 DCHECK_EQ(IrOpcode::kWord32Shl, node->opcode());
1044 Int32BinopMatcher m(node);
1045 if (m.right().Is(0)) return Replace(m.left().node()); // x << 0 => x
1046 if (m.IsFoldable()) { // K << K => K
1047 return ReplaceInt32(m.left().Value() << m.right().Value());
1048 }
1049 if (m.right().IsInRange(1, 31)) {
1050 // (x >>> K) << K => x & ~(2^K - 1)
1051 // (x >> K) << K => x & ~(2^K - 1)
1052 if (m.left().IsWord32Sar() || m.left().IsWord32Shr()) {
1053 Int32BinopMatcher mleft(m.left().node());
1054 if (mleft.right().Is(m.right().Value())) {
1055 node->ReplaceInput(0, mleft.left().node());
1056 node->ReplaceInput(1,
1057 Uint32Constant(~((1U << m.right().Value()) - 1U)));
1058 NodeProperties::ChangeOp(node, machine()->Word32And());
1059 Reduction reduction = ReduceWord32And(node);
1060 return reduction.Changed() ? reduction : Changed(node);
1061 }
1062 }
1063 }
1064 return ReduceWord32Shifts(node);
1065 }
1066
ReduceWord64Shl(Node * node)1067 Reduction MachineOperatorReducer::ReduceWord64Shl(Node* node) {
1068 DCHECK_EQ(IrOpcode::kWord64Shl, node->opcode());
1069 Int64BinopMatcher m(node);
1070 if (m.right().Is(0)) return Replace(m.left().node()); // x << 0 => x
1071 if (m.IsFoldable()) { // K << K => K
1072 return ReplaceInt64(m.left().Value() << m.right().Value());
1073 }
1074 return NoChange();
1075 }
1076
ReduceWord32Shr(Node * node)1077 Reduction MachineOperatorReducer::ReduceWord32Shr(Node* node) {
1078 Uint32BinopMatcher m(node);
1079 if (m.right().Is(0)) return Replace(m.left().node()); // x >>> 0 => x
1080 if (m.IsFoldable()) { // K >>> K => K
1081 return ReplaceInt32(m.left().Value() >> m.right().Value());
1082 }
1083 if (m.left().IsWord32And() && m.right().HasValue()) {
1084 Uint32BinopMatcher mleft(m.left().node());
1085 if (mleft.right().HasValue()) {
1086 uint32_t shift = m.right().Value() & 0x1F;
1087 uint32_t mask = mleft.right().Value();
1088 if ((mask >> shift) == 0) {
1089 // (m >>> s) == 0 implies ((x & m) >>> s) == 0
1090 return ReplaceInt32(0);
1091 }
1092 }
1093 }
1094 return ReduceWord32Shifts(node);
1095 }
1096
ReduceWord64Shr(Node * node)1097 Reduction MachineOperatorReducer::ReduceWord64Shr(Node* node) {
1098 DCHECK_EQ(IrOpcode::kWord64Shr, node->opcode());
1099 Uint64BinopMatcher m(node);
1100 if (m.right().Is(0)) return Replace(m.left().node()); // x >>> 0 => x
1101 if (m.IsFoldable()) { // K >> K => K
1102 return ReplaceInt64(m.left().Value() >> m.right().Value());
1103 }
1104 return NoChange();
1105 }
1106
ReduceWord32Sar(Node * node)1107 Reduction MachineOperatorReducer::ReduceWord32Sar(Node* node) {
1108 Int32BinopMatcher m(node);
1109 if (m.right().Is(0)) return Replace(m.left().node()); // x >> 0 => x
1110 if (m.IsFoldable()) { // K >> K => K
1111 return ReplaceInt32(m.left().Value() >> m.right().Value());
1112 }
1113 if (m.left().IsWord32Shl()) {
1114 Int32BinopMatcher mleft(m.left().node());
1115 if (mleft.left().IsComparison()) {
1116 if (m.right().Is(31) && mleft.right().Is(31)) {
1117 // Comparison << 31 >> 31 => 0 - Comparison
1118 node->ReplaceInput(0, Int32Constant(0));
1119 node->ReplaceInput(1, mleft.left().node());
1120 NodeProperties::ChangeOp(node, machine()->Int32Sub());
1121 Reduction const reduction = ReduceInt32Sub(node);
1122 return reduction.Changed() ? reduction : Changed(node);
1123 }
1124 } else if (mleft.left().IsLoad()) {
1125 LoadRepresentation const rep =
1126 LoadRepresentationOf(mleft.left().node()->op());
1127 if (m.right().Is(24) && mleft.right().Is(24) &&
1128 rep == MachineType::Int8()) {
1129 // Load[kMachInt8] << 24 >> 24 => Load[kMachInt8]
1130 return Replace(mleft.left().node());
1131 }
1132 if (m.right().Is(16) && mleft.right().Is(16) &&
1133 rep == MachineType::Int16()) {
1134 // Load[kMachInt16] << 16 >> 16 => Load[kMachInt8]
1135 return Replace(mleft.left().node());
1136 }
1137 }
1138 }
1139 return ReduceWord32Shifts(node);
1140 }
1141
ReduceWord64Sar(Node * node)1142 Reduction MachineOperatorReducer::ReduceWord64Sar(Node* node) {
1143 Int64BinopMatcher m(node);
1144 if (m.right().Is(0)) return Replace(m.left().node()); // x >> 0 => x
1145 if (m.IsFoldable()) {
1146 return ReplaceInt64(m.left().Value() >> m.right().Value());
1147 }
1148 return NoChange();
1149 }
1150
ReduceWord32And(Node * node)1151 Reduction MachineOperatorReducer::ReduceWord32And(Node* node) {
1152 DCHECK_EQ(IrOpcode::kWord32And, node->opcode());
1153 Int32BinopMatcher m(node);
1154 if (m.right().Is(0)) return Replace(m.right().node()); // x & 0 => 0
1155 if (m.right().Is(-1)) return Replace(m.left().node()); // x & -1 => x
1156 if (m.left().IsComparison() && m.right().Is(1)) { // CMP & 1 => CMP
1157 return Replace(m.left().node());
1158 }
1159 if (m.IsFoldable()) { // K & K => K
1160 return ReplaceInt32(m.left().Value() & m.right().Value());
1161 }
1162 if (m.LeftEqualsRight()) return Replace(m.left().node()); // x & x => x
1163 if (m.left().IsWord32And() && m.right().HasValue()) {
1164 Int32BinopMatcher mleft(m.left().node());
1165 if (mleft.right().HasValue()) { // (x & K) & K => x & K
1166 node->ReplaceInput(0, mleft.left().node());
1167 node->ReplaceInput(
1168 1, Int32Constant(m.right().Value() & mleft.right().Value()));
1169 Reduction const reduction = ReduceWord32And(node);
1170 return reduction.Changed() ? reduction : Changed(node);
1171 }
1172 }
1173 if (m.right().IsNegativePowerOf2()) {
1174 int32_t const mask = m.right().Value();
1175 if (m.left().IsWord32Shl()) {
1176 Uint32BinopMatcher mleft(m.left().node());
1177 if (mleft.right().HasValue() &&
1178 (mleft.right().Value() & 0x1F) >=
1179 base::bits::CountTrailingZeros(mask)) {
1180 // (x << L) & (-1 << K) => x << L iff L >= K
1181 return Replace(mleft.node());
1182 }
1183 } else if (m.left().IsInt32Add()) {
1184 Int32BinopMatcher mleft(m.left().node());
1185 if (mleft.right().HasValue() &&
1186 (mleft.right().Value() & mask) == mleft.right().Value()) {
1187 // (x + (K << L)) & (-1 << L) => (x & (-1 << L)) + (K << L)
1188 node->ReplaceInput(0, Word32And(mleft.left().node(), m.right().node()));
1189 node->ReplaceInput(1, mleft.right().node());
1190 NodeProperties::ChangeOp(node, machine()->Int32Add());
1191 Reduction const reduction = ReduceInt32Add(node);
1192 return reduction.Changed() ? reduction : Changed(node);
1193 }
1194 if (mleft.left().IsInt32Mul()) {
1195 Int32BinopMatcher mleftleft(mleft.left().node());
1196 if (mleftleft.right().IsMultipleOf(-mask)) {
1197 // (y * (K << L) + x) & (-1 << L) => (x & (-1 << L)) + y * (K << L)
1198 node->ReplaceInput(0,
1199 Word32And(mleft.right().node(), m.right().node()));
1200 node->ReplaceInput(1, mleftleft.node());
1201 NodeProperties::ChangeOp(node, machine()->Int32Add());
1202 Reduction const reduction = ReduceInt32Add(node);
1203 return reduction.Changed() ? reduction : Changed(node);
1204 }
1205 }
1206 if (mleft.right().IsInt32Mul()) {
1207 Int32BinopMatcher mleftright(mleft.right().node());
1208 if (mleftright.right().IsMultipleOf(-mask)) {
1209 // (x + y * (K << L)) & (-1 << L) => (x & (-1 << L)) + y * (K << L)
1210 node->ReplaceInput(0,
1211 Word32And(mleft.left().node(), m.right().node()));
1212 node->ReplaceInput(1, mleftright.node());
1213 NodeProperties::ChangeOp(node, machine()->Int32Add());
1214 Reduction const reduction = ReduceInt32Add(node);
1215 return reduction.Changed() ? reduction : Changed(node);
1216 }
1217 }
1218 if (mleft.left().IsWord32Shl()) {
1219 Int32BinopMatcher mleftleft(mleft.left().node());
1220 if (mleftleft.right().Is(base::bits::CountTrailingZeros(mask))) {
1221 // (y << L + x) & (-1 << L) => (x & (-1 << L)) + y << L
1222 node->ReplaceInput(0,
1223 Word32And(mleft.right().node(), m.right().node()));
1224 node->ReplaceInput(1, mleftleft.node());
1225 NodeProperties::ChangeOp(node, machine()->Int32Add());
1226 Reduction const reduction = ReduceInt32Add(node);
1227 return reduction.Changed() ? reduction : Changed(node);
1228 }
1229 }
1230 if (mleft.right().IsWord32Shl()) {
1231 Int32BinopMatcher mleftright(mleft.right().node());
1232 if (mleftright.right().Is(base::bits::CountTrailingZeros(mask))) {
1233 // (x + y << L) & (-1 << L) => (x & (-1 << L)) + y << L
1234 node->ReplaceInput(0,
1235 Word32And(mleft.left().node(), m.right().node()));
1236 node->ReplaceInput(1, mleftright.node());
1237 NodeProperties::ChangeOp(node, machine()->Int32Add());
1238 Reduction const reduction = ReduceInt32Add(node);
1239 return reduction.Changed() ? reduction : Changed(node);
1240 }
1241 }
1242 } else if (m.left().IsInt32Mul()) {
1243 Int32BinopMatcher mleft(m.left().node());
1244 if (mleft.right().IsMultipleOf(-mask)) {
1245 // (x * (K << L)) & (-1 << L) => x * (K << L)
1246 return Replace(mleft.node());
1247 }
1248 }
1249 }
1250 return NoChange();
1251 }
1252
TryMatchWord32Ror(Node * node)1253 Reduction MachineOperatorReducer::TryMatchWord32Ror(Node* node) {
1254 DCHECK(IrOpcode::kWord32Or == node->opcode() ||
1255 IrOpcode::kWord32Xor == node->opcode());
1256 Int32BinopMatcher m(node);
1257 Node* shl = nullptr;
1258 Node* shr = nullptr;
1259 // Recognize rotation, we are matching:
1260 // * x << y | x >>> (32 - y) => x ror (32 - y), i.e x rol y
1261 // * x << (32 - y) | x >>> y => x ror y
1262 // * x << y ^ x >>> (32 - y) => x ror (32 - y), i.e. x rol y
1263 // * x << (32 - y) ^ x >>> y => x ror y
1264 // as well as their commuted form.
1265 if (m.left().IsWord32Shl() && m.right().IsWord32Shr()) {
1266 shl = m.left().node();
1267 shr = m.right().node();
1268 } else if (m.left().IsWord32Shr() && m.right().IsWord32Shl()) {
1269 shl = m.right().node();
1270 shr = m.left().node();
1271 } else {
1272 return NoChange();
1273 }
1274
1275 Int32BinopMatcher mshl(shl);
1276 Int32BinopMatcher mshr(shr);
1277 if (mshl.left().node() != mshr.left().node()) return NoChange();
1278
1279 if (mshl.right().HasValue() && mshr.right().HasValue()) {
1280 // Case where y is a constant.
1281 if (mshl.right().Value() + mshr.right().Value() != 32) return NoChange();
1282 } else {
1283 Node* sub = nullptr;
1284 Node* y = nullptr;
1285 if (mshl.right().IsInt32Sub()) {
1286 sub = mshl.right().node();
1287 y = mshr.right().node();
1288 } else if (mshr.right().IsInt32Sub()) {
1289 sub = mshr.right().node();
1290 y = mshl.right().node();
1291 } else {
1292 return NoChange();
1293 }
1294
1295 Int32BinopMatcher msub(sub);
1296 if (!msub.left().Is(32) || msub.right().node() != y) return NoChange();
1297 }
1298
1299 node->ReplaceInput(0, mshl.left().node());
1300 node->ReplaceInput(1, mshr.right().node());
1301 NodeProperties::ChangeOp(node, machine()->Word32Ror());
1302 return Changed(node);
1303 }
1304
ReduceWord32Or(Node * node)1305 Reduction MachineOperatorReducer::ReduceWord32Or(Node* node) {
1306 DCHECK_EQ(IrOpcode::kWord32Or, node->opcode());
1307 Int32BinopMatcher m(node);
1308 if (m.right().Is(0)) return Replace(m.left().node()); // x | 0 => x
1309 if (m.right().Is(-1)) return Replace(m.right().node()); // x | -1 => -1
1310 if (m.IsFoldable()) { // K | K => K
1311 return ReplaceInt32(m.left().Value() | m.right().Value());
1312 }
1313 if (m.LeftEqualsRight()) return Replace(m.left().node()); // x | x => x
1314
1315 return TryMatchWord32Ror(node);
1316 }
1317
ReduceWord32Xor(Node * node)1318 Reduction MachineOperatorReducer::ReduceWord32Xor(Node* node) {
1319 DCHECK_EQ(IrOpcode::kWord32Xor, node->opcode());
1320 Int32BinopMatcher m(node);
1321 if (m.right().Is(0)) return Replace(m.left().node()); // x ^ 0 => x
1322 if (m.IsFoldable()) { // K ^ K => K
1323 return ReplaceInt32(m.left().Value() ^ m.right().Value());
1324 }
1325 if (m.LeftEqualsRight()) return ReplaceInt32(0); // x ^ x => 0
1326 if (m.left().IsWord32Xor() && m.right().Is(-1)) {
1327 Int32BinopMatcher mleft(m.left().node());
1328 if (mleft.right().Is(-1)) { // (x ^ -1) ^ -1 => x
1329 return Replace(mleft.left().node());
1330 }
1331 }
1332
1333 return TryMatchWord32Ror(node);
1334 }
1335
ReduceFloat64InsertLowWord32(Node * node)1336 Reduction MachineOperatorReducer::ReduceFloat64InsertLowWord32(Node* node) {
1337 DCHECK_EQ(IrOpcode::kFloat64InsertLowWord32, node->opcode());
1338 Float64Matcher mlhs(node->InputAt(0));
1339 Uint32Matcher mrhs(node->InputAt(1));
1340 if (mlhs.HasValue() && mrhs.HasValue()) {
1341 return ReplaceFloat64(bit_cast<double>(
1342 (bit_cast<uint64_t>(mlhs.Value()) & uint64_t{0xFFFFFFFF00000000}) |
1343 mrhs.Value()));
1344 }
1345 return NoChange();
1346 }
1347
1348
ReduceFloat64InsertHighWord32(Node * node)1349 Reduction MachineOperatorReducer::ReduceFloat64InsertHighWord32(Node* node) {
1350 DCHECK_EQ(IrOpcode::kFloat64InsertHighWord32, node->opcode());
1351 Float64Matcher mlhs(node->InputAt(0));
1352 Uint32Matcher mrhs(node->InputAt(1));
1353 if (mlhs.HasValue() && mrhs.HasValue()) {
1354 return ReplaceFloat64(bit_cast<double>(
1355 (bit_cast<uint64_t>(mlhs.Value()) & uint64_t{0xFFFFFFFF}) |
1356 (static_cast<uint64_t>(mrhs.Value()) << 32)));
1357 }
1358 return NoChange();
1359 }
1360
1361
1362 namespace {
1363
IsFloat64RepresentableAsFloat32(const Float64Matcher & m)1364 bool IsFloat64RepresentableAsFloat32(const Float64Matcher& m) {
1365 if (m.HasValue()) {
1366 double v = m.Value();
1367 float fv = static_cast<float>(v);
1368 return static_cast<double>(fv) == v;
1369 }
1370 return false;
1371 }
1372
1373 } // namespace
1374
1375
ReduceFloat64Compare(Node * node)1376 Reduction MachineOperatorReducer::ReduceFloat64Compare(Node* node) {
1377 DCHECK((IrOpcode::kFloat64Equal == node->opcode()) ||
1378 (IrOpcode::kFloat64LessThan == node->opcode()) ||
1379 (IrOpcode::kFloat64LessThanOrEqual == node->opcode()));
1380 // As all Float32 values have an exact representation in Float64, comparing
1381 // two Float64 values both converted from Float32 is equivalent to comparing
1382 // the original Float32s, so we can ignore the conversions. We can also reduce
1383 // comparisons of converted Float64 values against constants that can be
1384 // represented exactly as Float32.
1385 Float64BinopMatcher m(node);
1386 if ((m.left().IsChangeFloat32ToFloat64() &&
1387 m.right().IsChangeFloat32ToFloat64()) ||
1388 (m.left().IsChangeFloat32ToFloat64() &&
1389 IsFloat64RepresentableAsFloat32(m.right())) ||
1390 (IsFloat64RepresentableAsFloat32(m.left()) &&
1391 m.right().IsChangeFloat32ToFloat64())) {
1392 switch (node->opcode()) {
1393 case IrOpcode::kFloat64Equal:
1394 NodeProperties::ChangeOp(node, machine()->Float32Equal());
1395 break;
1396 case IrOpcode::kFloat64LessThan:
1397 NodeProperties::ChangeOp(node, machine()->Float32LessThan());
1398 break;
1399 case IrOpcode::kFloat64LessThanOrEqual:
1400 NodeProperties::ChangeOp(node, machine()->Float32LessThanOrEqual());
1401 break;
1402 default:
1403 return NoChange();
1404 }
1405 node->ReplaceInput(
1406 0, m.left().HasValue()
1407 ? Float32Constant(static_cast<float>(m.left().Value()))
1408 : m.left().InputAt(0));
1409 node->ReplaceInput(
1410 1, m.right().HasValue()
1411 ? Float32Constant(static_cast<float>(m.right().Value()))
1412 : m.right().InputAt(0));
1413 return Changed(node);
1414 }
1415 return NoChange();
1416 }
1417
ReduceFloat64RoundDown(Node * node)1418 Reduction MachineOperatorReducer::ReduceFloat64RoundDown(Node* node) {
1419 DCHECK_EQ(IrOpcode::kFloat64RoundDown, node->opcode());
1420 Float64Matcher m(node->InputAt(0));
1421 if (m.HasValue()) {
1422 return ReplaceFloat64(Floor(m.Value()));
1423 }
1424 return NoChange();
1425 }
1426
common() const1427 CommonOperatorBuilder* MachineOperatorReducer::common() const {
1428 return mcgraph()->common();
1429 }
1430
1431
machine() const1432 MachineOperatorBuilder* MachineOperatorReducer::machine() const {
1433 return mcgraph()->machine();
1434 }
1435
graph() const1436 Graph* MachineOperatorReducer::graph() const { return mcgraph()->graph(); }
1437
1438 } // namespace compiler
1439 } // namespace internal
1440 } // namespace v8
1441