LLVM 17.0.0git
InstCombineAddSub.cpp
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1//===- InstCombineAddSub.cpp ------------------------------------*- C++ -*-===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8//
9// This file implements the visit functions for add, fadd, sub, and fsub.
10//
11//===----------------------------------------------------------------------===//
12
13#include "InstCombineInternal.h"
14#include "llvm/ADT/APFloat.h"
15#include "llvm/ADT/APInt.h"
16#include "llvm/ADT/STLExtras.h"
20#include "llvm/IR/Constant.h"
21#include "llvm/IR/Constants.h"
22#include "llvm/IR/InstrTypes.h"
23#include "llvm/IR/Instruction.h"
25#include "llvm/IR/Operator.h"
27#include "llvm/IR/Type.h"
28#include "llvm/IR/Value.h"
33#include <cassert>
34#include <utility>
35
36using namespace llvm;
37using namespace PatternMatch;
38
39#define DEBUG_TYPE "instcombine"
40
41namespace {
42
43 /// Class representing coefficient of floating-point addend.
44 /// This class needs to be highly efficient, which is especially true for
45 /// the constructor. As of I write this comment, the cost of the default
46 /// constructor is merely 4-byte-store-zero (Assuming compiler is able to
47 /// perform write-merging).
48 ///
49 class FAddendCoef {
50 public:
51 // The constructor has to initialize a APFloat, which is unnecessary for
52 // most addends which have coefficient either 1 or -1. So, the constructor
53 // is expensive. In order to avoid the cost of the constructor, we should
54 // reuse some instances whenever possible. The pre-created instances
55 // FAddCombine::Add[0-5] embodies this idea.
56 FAddendCoef() = default;
57 ~FAddendCoef();
58
59 // If possible, don't define operator+/operator- etc because these
60 // operators inevitably call FAddendCoef's constructor which is not cheap.
61 void operator=(const FAddendCoef &A);
62 void operator+=(const FAddendCoef &A);
63 void operator*=(const FAddendCoef &S);
64
65 void set(short C) {
66 assert(!insaneIntVal(C) && "Insane coefficient");
67 IsFp = false; IntVal = C;
68 }
69
70 void set(const APFloat& C);
71
72 void negate();
73
74 bool isZero() const { return isInt() ? !IntVal : getFpVal().isZero(); }
75 Value *getValue(Type *) const;
76
77 bool isOne() const { return isInt() && IntVal == 1; }
78 bool isTwo() const { return isInt() && IntVal == 2; }
79 bool isMinusOne() const { return isInt() && IntVal == -1; }
80 bool isMinusTwo() const { return isInt() && IntVal == -2; }
81
82 private:
83 bool insaneIntVal(int V) { return V > 4 || V < -4; }
84
85 APFloat *getFpValPtr() { return reinterpret_cast<APFloat *>(&FpValBuf); }
86
87 const APFloat *getFpValPtr() const {
88 return reinterpret_cast<const APFloat *>(&FpValBuf);
89 }
90
91 const APFloat &getFpVal() const {
92 assert(IsFp && BufHasFpVal && "Incorret state");
93 return *getFpValPtr();
94 }
95
96 APFloat &getFpVal() {
97 assert(IsFp && BufHasFpVal && "Incorret state");
98 return *getFpValPtr();
99 }
100
101 bool isInt() const { return !IsFp; }
102
103 // If the coefficient is represented by an integer, promote it to a
104 // floating point.
105 void convertToFpType(const fltSemantics &Sem);
106
107 // Construct an APFloat from a signed integer.
108 // TODO: We should get rid of this function when APFloat can be constructed
109 // from an *SIGNED* integer.
110 APFloat createAPFloatFromInt(const fltSemantics &Sem, int Val);
111
112 bool IsFp = false;
113
114 // True iff FpValBuf contains an instance of APFloat.
115 bool BufHasFpVal = false;
116
117 // The integer coefficient of an individual addend is either 1 or -1,
118 // and we try to simplify at most 4 addends from neighboring at most
119 // two instructions. So the range of <IntVal> falls in [-4, 4]. APInt
120 // is overkill of this end.
121 short IntVal = 0;
122
124 };
125
126 /// FAddend is used to represent floating-point addend. An addend is
127 /// represented as <C, V>, where the V is a symbolic value, and C is a
128 /// constant coefficient. A constant addend is represented as <C, 0>.
129 class FAddend {
130 public:
131 FAddend() = default;
132
133 void operator+=(const FAddend &T) {
134 assert((Val == T.Val) && "Symbolic-values disagree");
135 Coeff += T.Coeff;
136 }
137
138 Value *getSymVal() const { return Val; }
139 const FAddendCoef &getCoef() const { return Coeff; }
140
141 bool isConstant() const { return Val == nullptr; }
142 bool isZero() const { return Coeff.isZero(); }
143
144 void set(short Coefficient, Value *V) {
145 Coeff.set(Coefficient);
146 Val = V;
147 }
148 void set(const APFloat &Coefficient, Value *V) {
149 Coeff.set(Coefficient);
150 Val = V;
151 }
152 void set(const ConstantFP *Coefficient, Value *V) {
153 Coeff.set(Coefficient->getValueAPF());
154 Val = V;
155 }
156
157 void negate() { Coeff.negate(); }
158
159 /// Drill down the U-D chain one step to find the definition of V, and
160 /// try to break the definition into one or two addends.
161 static unsigned drillValueDownOneStep(Value* V, FAddend &A0, FAddend &A1);
162
163 /// Similar to FAddend::drillDownOneStep() except that the value being
164 /// splitted is the addend itself.
165 unsigned drillAddendDownOneStep(FAddend &Addend0, FAddend &Addend1) const;
166
167 private:
168 void Scale(const FAddendCoef& ScaleAmt) { Coeff *= ScaleAmt; }
169
170 // This addend has the value of "Coeff * Val".
171 Value *Val = nullptr;
172 FAddendCoef Coeff;
173 };
174
175 /// FAddCombine is the class for optimizing an unsafe fadd/fsub along
176 /// with its neighboring at most two instructions.
177 ///
178 class FAddCombine {
179 public:
180 FAddCombine(InstCombiner::BuilderTy &B) : Builder(B) {}
181
183
184 private:
185 using AddendVect = SmallVector<const FAddend *, 4>;
186
187 Value *simplifyFAdd(AddendVect& V, unsigned InstrQuota);
188
189 /// Convert given addend to a Value
190 Value *createAddendVal(const FAddend &A, bool& NeedNeg);
191
192 /// Return the number of instructions needed to emit the N-ary addition.
193 unsigned calcInstrNumber(const AddendVect& Vect);
194
195 Value *createFSub(Value *Opnd0, Value *Opnd1);
196 Value *createFAdd(Value *Opnd0, Value *Opnd1);
197 Value *createFMul(Value *Opnd0, Value *Opnd1);
198 Value *createFNeg(Value *V);
199 Value *createNaryFAdd(const AddendVect& Opnds, unsigned InstrQuota);
200 void createInstPostProc(Instruction *NewInst, bool NoNumber = false);
201
202 // Debugging stuff are clustered here.
203 #ifndef NDEBUG
204 unsigned CreateInstrNum;
205 void initCreateInstNum() { CreateInstrNum = 0; }
206 void incCreateInstNum() { CreateInstrNum++; }
207 #else
208 void initCreateInstNum() {}
209 void incCreateInstNum() {}
210 #endif
211
213 Instruction *Instr = nullptr;
214 };
215
216} // end anonymous namespace
217
218//===----------------------------------------------------------------------===//
219//
220// Implementation of
221// {FAddendCoef, FAddend, FAddition, FAddCombine}.
222//
223//===----------------------------------------------------------------------===//
224FAddendCoef::~FAddendCoef() {
225 if (BufHasFpVal)
226 getFpValPtr()->~APFloat();
227}
228
229void FAddendCoef::set(const APFloat& C) {
230 APFloat *P = getFpValPtr();
231
232 if (isInt()) {
233 // As the buffer is meanless byte stream, we cannot call
234 // APFloat::operator=().
235 new(P) APFloat(C);
236 } else
237 *P = C;
238
239 IsFp = BufHasFpVal = true;
240}
241
242void FAddendCoef::convertToFpType(const fltSemantics &Sem) {
243 if (!isInt())
244 return;
245
246 APFloat *P = getFpValPtr();
247 if (IntVal > 0)
248 new(P) APFloat(Sem, IntVal);
249 else {
250 new(P) APFloat(Sem, 0 - IntVal);
251 P->changeSign();
252 }
253 IsFp = BufHasFpVal = true;
254}
255
256APFloat FAddendCoef::createAPFloatFromInt(const fltSemantics &Sem, int Val) {
257 if (Val >= 0)
258 return APFloat(Sem, Val);
259
260 APFloat T(Sem, 0 - Val);
261 T.changeSign();
262
263 return T;
264}
265
266void FAddendCoef::operator=(const FAddendCoef &That) {
267 if (That.isInt())
268 set(That.IntVal);
269 else
270 set(That.getFpVal());
271}
272
273void FAddendCoef::operator+=(const FAddendCoef &That) {
274 RoundingMode RndMode = RoundingMode::NearestTiesToEven;
275 if (isInt() == That.isInt()) {
276 if (isInt())
277 IntVal += That.IntVal;
278 else
279 getFpVal().add(That.getFpVal(), RndMode);
280 return;
281 }
282
283 if (isInt()) {
284 const APFloat &T = That.getFpVal();
285 convertToFpType(T.getSemantics());
286 getFpVal().add(T, RndMode);
287 return;
288 }
289
290 APFloat &T = getFpVal();
291 T.add(createAPFloatFromInt(T.getSemantics(), That.IntVal), RndMode);
292}
293
294void FAddendCoef::operator*=(const FAddendCoef &That) {
295 if (That.isOne())
296 return;
297
298 if (That.isMinusOne()) {
299 negate();
300 return;
301 }
302
303 if (isInt() && That.isInt()) {
304 int Res = IntVal * (int)That.IntVal;
305 assert(!insaneIntVal(Res) && "Insane int value");
306 IntVal = Res;
307 return;
308 }
309
310 const fltSemantics &Semantic =
311 isInt() ? That.getFpVal().getSemantics() : getFpVal().getSemantics();
312
313 if (isInt())
314 convertToFpType(Semantic);
315 APFloat &F0 = getFpVal();
316
317 if (That.isInt())
318 F0.multiply(createAPFloatFromInt(Semantic, That.IntVal),
319 APFloat::rmNearestTiesToEven);
320 else
321 F0.multiply(That.getFpVal(), APFloat::rmNearestTiesToEven);
322}
323
324void FAddendCoef::negate() {
325 if (isInt())
326 IntVal = 0 - IntVal;
327 else
328 getFpVal().changeSign();
329}
330
331Value *FAddendCoef::getValue(Type *Ty) const {
332 return isInt() ?
333 ConstantFP::get(Ty, float(IntVal)) :
334 ConstantFP::get(Ty->getContext(), getFpVal());
335}
336
337// The definition of <Val> Addends
338// =========================================
339// A + B <1, A>, <1,B>
340// A - B <1, A>, <1,B>
341// 0 - B <-1, B>
342// C * A, <C, A>
343// A + C <1, A> <C, NULL>
344// 0 +/- 0 <0, NULL> (corner case)
345//
346// Legend: A and B are not constant, C is constant
347unsigned FAddend::drillValueDownOneStep
348 (Value *Val, FAddend &Addend0, FAddend &Addend1) {
349 Instruction *I = nullptr;
350 if (!Val || !(I = dyn_cast<Instruction>(Val)))
351 return 0;
352
353 unsigned Opcode = I->getOpcode();
354
355 if (Opcode == Instruction::FAdd || Opcode == Instruction::FSub) {
356 ConstantFP *C0, *C1;
357 Value *Opnd0 = I->getOperand(0);
358 Value *Opnd1 = I->getOperand(1);
359 if ((C0 = dyn_cast<ConstantFP>(Opnd0)) && C0->isZero())
360 Opnd0 = nullptr;
361
362 if ((C1 = dyn_cast<ConstantFP>(Opnd1)) && C1->isZero())
363 Opnd1 = nullptr;
364
365 if (Opnd0) {
366 if (!C0)
367 Addend0.set(1, Opnd0);
368 else
369 Addend0.set(C0, nullptr);
370 }
371
372 if (Opnd1) {
373 FAddend &Addend = Opnd0 ? Addend1 : Addend0;
374 if (!C1)
375 Addend.set(1, Opnd1);
376 else
377 Addend.set(C1, nullptr);
378 if (Opcode == Instruction::FSub)
379 Addend.negate();
380 }
381
382 if (Opnd0 || Opnd1)
383 return Opnd0 && Opnd1 ? 2 : 1;
384
385 // Both operands are zero. Weird!
386 Addend0.set(APFloat(C0->getValueAPF().getSemantics()), nullptr);
387 return 1;
388 }
389
390 if (I->getOpcode() == Instruction::FMul) {
391 Value *V0 = I->getOperand(0);
392 Value *V1 = I->getOperand(1);
393 if (ConstantFP *C = dyn_cast<ConstantFP>(V0)) {
394 Addend0.set(C, V1);
395 return 1;
396 }
397
398 if (ConstantFP *C = dyn_cast<ConstantFP>(V1)) {
399 Addend0.set(C, V0);
400 return 1;
401 }
402 }
403
404 return 0;
405}
406
407// Try to break *this* addend into two addends. e.g. Suppose this addend is
408// <2.3, V>, and V = X + Y, by calling this function, we obtain two addends,
409// i.e. <2.3, X> and <2.3, Y>.
410unsigned FAddend::drillAddendDownOneStep
411 (FAddend &Addend0, FAddend &Addend1) const {
412 if (isConstant())
413 return 0;
414
415 unsigned BreakNum = FAddend::drillValueDownOneStep(Val, Addend0, Addend1);
416 if (!BreakNum || Coeff.isOne())
417 return BreakNum;
418
419 Addend0.Scale(Coeff);
420
421 if (BreakNum == 2)
422 Addend1.Scale(Coeff);
423
424 return BreakNum;
425}
426
427Value *FAddCombine::simplify(Instruction *I) {
428 assert(I->hasAllowReassoc() && I->hasNoSignedZeros() &&
429 "Expected 'reassoc'+'nsz' instruction");
430
431 // Currently we are not able to handle vector type.
432 if (I->getType()->isVectorTy())
433 return nullptr;
434
435 assert((I->getOpcode() == Instruction::FAdd ||
436 I->getOpcode() == Instruction::FSub) && "Expect add/sub");
437
438 // Save the instruction before calling other member-functions.
439 Instr = I;
440
441 FAddend Opnd0, Opnd1, Opnd0_0, Opnd0_1, Opnd1_0, Opnd1_1;
442
443 unsigned OpndNum = FAddend::drillValueDownOneStep(I, Opnd0, Opnd1);
444
445 // Step 1: Expand the 1st addend into Opnd0_0 and Opnd0_1.
446 unsigned Opnd0_ExpNum = 0;
447 unsigned Opnd1_ExpNum = 0;
448
449 if (!Opnd0.isConstant())
450 Opnd0_ExpNum = Opnd0.drillAddendDownOneStep(Opnd0_0, Opnd0_1);
451
452 // Step 2: Expand the 2nd addend into Opnd1_0 and Opnd1_1.
453 if (OpndNum == 2 && !Opnd1.isConstant())
454 Opnd1_ExpNum = Opnd1.drillAddendDownOneStep(Opnd1_0, Opnd1_1);
455
456 // Step 3: Try to optimize Opnd0_0 + Opnd0_1 + Opnd1_0 + Opnd1_1
457 if (Opnd0_ExpNum && Opnd1_ExpNum) {
458 AddendVect AllOpnds;
459 AllOpnds.push_back(&Opnd0_0);
460 AllOpnds.push_back(&Opnd1_0);
461 if (Opnd0_ExpNum == 2)
462 AllOpnds.push_back(&Opnd0_1);
463 if (Opnd1_ExpNum == 2)
464 AllOpnds.push_back(&Opnd1_1);
465
466 // Compute instruction quota. We should save at least one instruction.
467 unsigned InstQuota = 0;
468
469 Value *V0 = I->getOperand(0);
470 Value *V1 = I->getOperand(1);
471 InstQuota = ((!isa<Constant>(V0) && V0->hasOneUse()) &&
472 (!isa<Constant>(V1) && V1->hasOneUse())) ? 2 : 1;
473
474 if (Value *R = simplifyFAdd(AllOpnds, InstQuota))
475 return R;
476 }
477
478 if (OpndNum != 2) {
479 // The input instruction is : "I=0.0 +/- V". If the "V" were able to be
480 // splitted into two addends, say "V = X - Y", the instruction would have
481 // been optimized into "I = Y - X" in the previous steps.
482 //
483 const FAddendCoef &CE = Opnd0.getCoef();
484 return CE.isOne() ? Opnd0.getSymVal() : nullptr;
485 }
486
487 // step 4: Try to optimize Opnd0 + Opnd1_0 [+ Opnd1_1]
488 if (Opnd1_ExpNum) {
489 AddendVect AllOpnds;
490 AllOpnds.push_back(&Opnd0);
491 AllOpnds.push_back(&Opnd1_0);
492 if (Opnd1_ExpNum == 2)
493 AllOpnds.push_back(&Opnd1_1);
494
495 if (Value *R = simplifyFAdd(AllOpnds, 1))
496 return R;
497 }
498
499 // step 5: Try to optimize Opnd1 + Opnd0_0 [+ Opnd0_1]
500 if (Opnd0_ExpNum) {
501 AddendVect AllOpnds;
502 AllOpnds.push_back(&Opnd1);
503 AllOpnds.push_back(&Opnd0_0);
504 if (Opnd0_ExpNum == 2)
505 AllOpnds.push_back(&Opnd0_1);
506
507 if (Value *R = simplifyFAdd(AllOpnds, 1))
508 return R;
509 }
510
511 return nullptr;
512}
513
514Value *FAddCombine::simplifyFAdd(AddendVect& Addends, unsigned InstrQuota) {
515 unsigned AddendNum = Addends.size();
516 assert(AddendNum <= 4 && "Too many addends");
517
518 // For saving intermediate results;
519 unsigned NextTmpIdx = 0;
520 FAddend TmpResult[3];
521
522 // Simplified addends are placed <SimpVect>.
523 AddendVect SimpVect;
524
525 // The outer loop works on one symbolic-value at a time. Suppose the input
526 // addends are : <a1, x>, <b1, y>, <a2, x>, <c1, z>, <b2, y>, ...
527 // The symbolic-values will be processed in this order: x, y, z.
528 for (unsigned SymIdx = 0; SymIdx < AddendNum; SymIdx++) {
529
530 const FAddend *ThisAddend = Addends[SymIdx];
531 if (!ThisAddend) {
532 // This addend was processed before.
533 continue;
534 }
535
536 Value *Val = ThisAddend->getSymVal();
537
538 // If the resulting expr has constant-addend, this constant-addend is
539 // desirable to reside at the top of the resulting expression tree. Placing
540 // constant close to super-expr(s) will potentially reveal some
541 // optimization opportunities in super-expr(s). Here we do not implement
542 // this logic intentionally and rely on SimplifyAssociativeOrCommutative
543 // call later.
544
545 unsigned StartIdx = SimpVect.size();
546 SimpVect.push_back(ThisAddend);
547
548 // The inner loop collects addends sharing same symbolic-value, and these
549 // addends will be later on folded into a single addend. Following above
550 // example, if the symbolic value "y" is being processed, the inner loop
551 // will collect two addends "<b1,y>" and "<b2,Y>". These two addends will
552 // be later on folded into "<b1+b2, y>".
553 for (unsigned SameSymIdx = SymIdx + 1;
554 SameSymIdx < AddendNum; SameSymIdx++) {
555 const FAddend *T = Addends[SameSymIdx];
556 if (T && T->getSymVal() == Val) {
557 // Set null such that next iteration of the outer loop will not process
558 // this addend again.
559 Addends[SameSymIdx] = nullptr;
560 SimpVect.push_back(T);
561 }
562 }
563
564 // If multiple addends share same symbolic value, fold them together.
565 if (StartIdx + 1 != SimpVect.size()) {
566 FAddend &R = TmpResult[NextTmpIdx ++];
567 R = *SimpVect[StartIdx];
568 for (unsigned Idx = StartIdx + 1; Idx < SimpVect.size(); Idx++)
569 R += *SimpVect[Idx];
570
571 // Pop all addends being folded and push the resulting folded addend.
572 SimpVect.resize(StartIdx);
573 if (!R.isZero()) {
574 SimpVect.push_back(&R);
575 }
576 }
577 }
578
579 assert((NextTmpIdx <= std::size(TmpResult) + 1) && "out-of-bound access");
580
581 Value *Result;
582 if (!SimpVect.empty())
583 Result = createNaryFAdd(SimpVect, InstrQuota);
584 else {
585 // The addition is folded to 0.0.
586 Result = ConstantFP::get(Instr->getType(), 0.0);
587 }
588
589 return Result;
590}
591
592Value *FAddCombine::createNaryFAdd
593 (const AddendVect &Opnds, unsigned InstrQuota) {
594 assert(!Opnds.empty() && "Expect at least one addend");
595
596 // Step 1: Check if the # of instructions needed exceeds the quota.
597
598 unsigned InstrNeeded = calcInstrNumber(Opnds);
599 if (InstrNeeded > InstrQuota)
600 return nullptr;
601
602 initCreateInstNum();
603
604 // step 2: Emit the N-ary addition.
605 // Note that at most three instructions are involved in Fadd-InstCombine: the
606 // addition in question, and at most two neighboring instructions.
607 // The resulting optimized addition should have at least one less instruction
608 // than the original addition expression tree. This implies that the resulting
609 // N-ary addition has at most two instructions, and we don't need to worry
610 // about tree-height when constructing the N-ary addition.
611
612 Value *LastVal = nullptr;
613 bool LastValNeedNeg = false;
614
615 // Iterate the addends, creating fadd/fsub using adjacent two addends.
616 for (const FAddend *Opnd : Opnds) {
617 bool NeedNeg;
618 Value *V = createAddendVal(*Opnd, NeedNeg);
619 if (!LastVal) {
620 LastVal = V;
621 LastValNeedNeg = NeedNeg;
622 continue;
623 }
624
625 if (LastValNeedNeg == NeedNeg) {
626 LastVal = createFAdd(LastVal, V);
627 continue;
628 }
629
630 if (LastValNeedNeg)
631 LastVal = createFSub(V, LastVal);
632 else
633 LastVal = createFSub(LastVal, V);
634
635 LastValNeedNeg = false;
636 }
637
638 if (LastValNeedNeg) {
639 LastVal = createFNeg(LastVal);
640 }
641
642#ifndef NDEBUG
643 assert(CreateInstrNum == InstrNeeded &&
644 "Inconsistent in instruction numbers");
645#endif
646
647 return LastVal;
648}
649
650Value *FAddCombine::createFSub(Value *Opnd0, Value *Opnd1) {
651 Value *V = Builder.CreateFSub(Opnd0, Opnd1);
652 if (Instruction *I = dyn_cast<Instruction>(V))
653 createInstPostProc(I);
654 return V;
655}
656
657Value *FAddCombine::createFNeg(Value *V) {
658 Value *NewV = Builder.CreateFNeg(V);
659 if (Instruction *I = dyn_cast<Instruction>(NewV))
660 createInstPostProc(I, true); // fneg's don't receive instruction numbers.
661 return NewV;
662}
663
664Value *FAddCombine::createFAdd(Value *Opnd0, Value *Opnd1) {
665 Value *V = Builder.CreateFAdd(Opnd0, Opnd1);
666 if (Instruction *I = dyn_cast<Instruction>(V))
667 createInstPostProc(I);
668 return V;
669}
670
671Value *FAddCombine::createFMul(Value *Opnd0, Value *Opnd1) {
672 Value *V = Builder.CreateFMul(Opnd0, Opnd1);
673 if (Instruction *I = dyn_cast<Instruction>(V))
674 createInstPostProc(I);
675 return V;
676}
677
678void FAddCombine::createInstPostProc(Instruction *NewInstr, bool NoNumber) {
679 NewInstr->setDebugLoc(Instr->getDebugLoc());
680
681 // Keep track of the number of instruction created.
682 if (!NoNumber)
683 incCreateInstNum();
684
685 // Propagate fast-math flags
686 NewInstr->setFastMathFlags(Instr->getFastMathFlags());
687}
688
689// Return the number of instruction needed to emit the N-ary addition.
690// NOTE: Keep this function in sync with createAddendVal().
691unsigned FAddCombine::calcInstrNumber(const AddendVect &Opnds) {
692 unsigned OpndNum = Opnds.size();
693 unsigned InstrNeeded = OpndNum - 1;
694
695 // Adjust the number of instructions needed to emit the N-ary add.
696 for (const FAddend *Opnd : Opnds) {
697 if (Opnd->isConstant())
698 continue;
699
700 // The constant check above is really for a few special constant
701 // coefficients.
702 if (isa<UndefValue>(Opnd->getSymVal()))
703 continue;
704
705 const FAddendCoef &CE = Opnd->getCoef();
706 // Let the addend be "c * x". If "c == +/-1", the value of the addend
707 // is immediately available; otherwise, it needs exactly one instruction
708 // to evaluate the value.
709 if (!CE.isMinusOne() && !CE.isOne())
710 InstrNeeded++;
711 }
712 return InstrNeeded;
713}
714
715// Input Addend Value NeedNeg(output)
716// ================================================================
717// Constant C C false
718// <+/-1, V> V coefficient is -1
719// <2/-2, V> "fadd V, V" coefficient is -2
720// <C, V> "fmul V, C" false
721//
722// NOTE: Keep this function in sync with FAddCombine::calcInstrNumber.
723Value *FAddCombine::createAddendVal(const FAddend &Opnd, bool &NeedNeg) {
724 const FAddendCoef &Coeff = Opnd.getCoef();
725
726 if (Opnd.isConstant()) {
727 NeedNeg = false;
728 return Coeff.getValue(Instr->getType());
729 }
730
731 Value *OpndVal = Opnd.getSymVal();
732
733 if (Coeff.isMinusOne() || Coeff.isOne()) {
734 NeedNeg = Coeff.isMinusOne();
735 return OpndVal;
736 }
737
738 if (Coeff.isTwo() || Coeff.isMinusTwo()) {
739 NeedNeg = Coeff.isMinusTwo();
740 return createFAdd(OpndVal, OpndVal);
741 }
742
743 NeedNeg = false;
744 return createFMul(OpndVal, Coeff.getValue(Instr->getType()));
745}
746
747// Checks if any operand is negative and we can convert add to sub.
748// This function checks for following negative patterns
749// ADD(XOR(OR(Z, NOT(C)), C)), 1) == NEG(AND(Z, C))
750// ADD(XOR(AND(Z, C), C), 1) == NEG(OR(Z, ~C))
751// XOR(AND(Z, C), (C + 1)) == NEG(OR(Z, ~C)) if C is even
753 InstCombiner::BuilderTy &Builder) {
754 Value *LHS = I.getOperand(0), *RHS = I.getOperand(1);
755
756 // This function creates 2 instructions to replace ADD, we need at least one
757 // of LHS or RHS to have one use to ensure benefit in transform.
758 if (!LHS->hasOneUse() && !RHS->hasOneUse())
759 return nullptr;
760
761 Value *X = nullptr, *Y = nullptr, *Z = nullptr;
762 const APInt *C1 = nullptr, *C2 = nullptr;
763
764 // if ONE is on other side, swap
765 if (match(RHS, m_Add(m_Value(X), m_One())))
766 std::swap(LHS, RHS);
767
768 if (match(LHS, m_Add(m_Value(X), m_One()))) {
769 // if XOR on other side, swap
770 if (match(RHS, m_Xor(m_Value(Y), m_APInt(C1))))
771 std::swap(X, RHS);
772
773 if (match(X, m_Xor(m_Value(Y), m_APInt(C1)))) {
774 // X = XOR(Y, C1), Y = OR(Z, C2), C2 = NOT(C1) ==> X == NOT(AND(Z, C1))
775 // ADD(ADD(X, 1), RHS) == ADD(X, ADD(RHS, 1)) == SUB(RHS, AND(Z, C1))
776 if (match(Y, m_Or(m_Value(Z), m_APInt(C2))) && (*C2 == ~(*C1))) {
777 Value *NewAnd = Builder.CreateAnd(Z, *C1);
778 return Builder.CreateSub(RHS, NewAnd, "sub");
779 } else if (match(Y, m_And(m_Value(Z), m_APInt(C2))) && (*C1 == *C2)) {
780 // X = XOR(Y, C1), Y = AND(Z, C2), C2 == C1 ==> X == NOT(OR(Z, ~C1))
781 // ADD(ADD(X, 1), RHS) == ADD(X, ADD(RHS, 1)) == SUB(RHS, OR(Z, ~C1))
782 Value *NewOr = Builder.CreateOr(Z, ~(*C1));
783 return Builder.CreateSub(RHS, NewOr, "sub");
784 }
785 }
786 }
787
788 // Restore LHS and RHS
789 LHS = I.getOperand(0);
790 RHS = I.getOperand(1);
791
792 // if XOR is on other side, swap
793 if (match(RHS, m_Xor(m_Value(Y), m_APInt(C1))))
794 std::swap(LHS, RHS);
795
796 // C2 is ODD
797 // LHS = XOR(Y, C1), Y = AND(Z, C2), C1 == (C2 + 1) => LHS == NEG(OR(Z, ~C2))
798 // ADD(LHS, RHS) == SUB(RHS, OR(Z, ~C2))
799 if (match(LHS, m_Xor(m_Value(Y), m_APInt(C1))))
800 if (C1->countr_zero() == 0)
801 if (match(Y, m_And(m_Value(Z), m_APInt(C2))) && *C1 == (*C2 + 1)) {
802 Value *NewOr = Builder.CreateOr(Z, ~(*C2));
803 return Builder.CreateSub(RHS, NewOr, "sub");
804 }
805 return nullptr;
806}
807
808/// Wrapping flags may allow combining constants separated by an extend.
810 InstCombiner::BuilderTy &Builder) {
811 Value *Op0 = Add.getOperand(0), *Op1 = Add.getOperand(1);
812 Type *Ty = Add.getType();
813 Constant *Op1C;
814 if (!match(Op1, m_Constant(Op1C)))
815 return nullptr;
816
817 // Try this match first because it results in an add in the narrow type.
818 // (zext (X +nuw C2)) + C1 --> zext (X + (C2 + trunc(C1)))
819 Value *X;
820 const APInt *C1, *C2;
821 if (match(Op1, m_APInt(C1)) &&
822 match(Op0, m_OneUse(m_ZExt(m_NUWAdd(m_Value(X), m_APInt(C2))))) &&
823 C1->isNegative() && C1->sge(-C2->sext(C1->getBitWidth()))) {
824 Constant *NewC =
825 ConstantInt::get(X->getType(), *C2 + C1->trunc(C2->getBitWidth()));
826 return new ZExtInst(Builder.CreateNUWAdd(X, NewC), Ty);
827 }
828
829 // More general combining of constants in the wide type.
830 // (sext (X +nsw NarrowC)) + C --> (sext X) + (sext(NarrowC) + C)
831 Constant *NarrowC;
832 if (match(Op0, m_OneUse(m_SExt(m_NSWAdd(m_Value(X), m_Constant(NarrowC)))))) {
833 Constant *WideC = ConstantExpr::getSExt(NarrowC, Ty);
834 Constant *NewC = ConstantExpr::getAdd(WideC, Op1C);
835 Value *WideX = Builder.CreateSExt(X, Ty);
836 return BinaryOperator::CreateAdd(WideX, NewC);
837 }
838 // (zext (X +nuw NarrowC)) + C --> (zext X) + (zext(NarrowC) + C)
839 if (match(Op0, m_OneUse(m_ZExt(m_NUWAdd(m_Value(X), m_Constant(NarrowC)))))) {
840 Constant *WideC = ConstantExpr::getZExt(NarrowC, Ty);
841 Constant *NewC = ConstantExpr::getAdd(WideC, Op1C);
842 Value *WideX = Builder.CreateZExt(X, Ty);
843 return BinaryOperator::CreateAdd(WideX, NewC);
844 }
845
846 return nullptr;
847}
848
850 Value *Op0 = Add.getOperand(0), *Op1 = Add.getOperand(1);
851 Type *Ty = Add.getType();
852 Constant *Op1C;
853 if (!match(Op1, m_ImmConstant(Op1C)))
854 return nullptr;
855
857 return NV;
858
859 Value *X;
860 Constant *Op00C;
861
862 // add (sub C1, X), C2 --> sub (add C1, C2), X
863 if (match(Op0, m_Sub(m_Constant(Op00C), m_Value(X))))
864 return BinaryOperator::CreateSub(ConstantExpr::getAdd(Op00C, Op1C), X);
865
866 Value *Y;
867
868 // add (sub X, Y), -1 --> add (not Y), X
869 if (match(Op0, m_OneUse(m_Sub(m_Value(X), m_Value(Y)))) &&
870 match(Op1, m_AllOnes()))
871 return BinaryOperator::CreateAdd(Builder.CreateNot(Y), X);
872
873 // zext(bool) + C -> bool ? C + 1 : C
874 if (match(Op0, m_ZExt(m_Value(X))) &&
875 X->getType()->getScalarSizeInBits() == 1)
876 return SelectInst::Create(X, InstCombiner::AddOne(Op1C), Op1);
877 // sext(bool) + C -> bool ? C - 1 : C
878 if (match(Op0, m_SExt(m_Value(X))) &&
879 X->getType()->getScalarSizeInBits() == 1)
880 return SelectInst::Create(X, InstCombiner::SubOne(Op1C), Op1);
881
882 // ~X + C --> (C-1) - X
883 if (match(Op0, m_Not(m_Value(X))))
884 return BinaryOperator::CreateSub(InstCombiner::SubOne(Op1C), X);
885
886 // (iN X s>> (N - 1)) + 1 --> zext (X > -1)
887 const APInt *C;
888 unsigned BitWidth = Ty->getScalarSizeInBits();
889 if (match(Op0, m_OneUse(m_AShr(m_Value(X),
891 match(Op1, m_One()))
892 return new ZExtInst(Builder.CreateIsNotNeg(X, "isnotneg"), Ty);
893
894 if (!match(Op1, m_APInt(C)))
895 return nullptr;
896
897 // (X | Op01C) + Op1C --> X + (Op01C + Op1C) iff the `or` is actually an `add`
898 Constant *Op01C;
899 if (match(Op0, m_Or(m_Value(X), m_ImmConstant(Op01C))) &&
900 haveNoCommonBitsSet(X, Op01C, DL, &AC, &Add, &DT))
901 return BinaryOperator::CreateAdd(X, ConstantExpr::getAdd(Op01C, Op1C));
902
903 // (X | C2) + C --> (X | C2) ^ C2 iff (C2 == -C)
904 const APInt *C2;
905 if (match(Op0, m_Or(m_Value(), m_APInt(C2))) && *C2 == -*C)
906 return BinaryOperator::CreateXor(Op0, ConstantInt::get(Add.getType(), *C2));
907
908 if (C->isSignMask()) {
909 // If wrapping is not allowed, then the addition must set the sign bit:
910 // X + (signmask) --> X | signmask
911 if (Add.hasNoSignedWrap() || Add.hasNoUnsignedWrap())
912 return BinaryOperator::CreateOr(Op0, Op1);
913
914 // If wrapping is allowed, then the addition flips the sign bit of LHS:
915 // X + (signmask) --> X ^ signmask
916 return BinaryOperator::CreateXor(Op0, Op1);
917 }
918
919 // Is this add the last step in a convoluted sext?
920 // add(zext(xor i16 X, -32768), -32768) --> sext X
921 if (match(Op0, m_ZExt(m_Xor(m_Value(X), m_APInt(C2)))) &&
922 C2->isMinSignedValue() && C2->sext(Ty->getScalarSizeInBits()) == *C)
923 return CastInst::Create(Instruction::SExt, X, Ty);
924
925 if (match(Op0, m_Xor(m_Value(X), m_APInt(C2)))) {
926 // (X ^ signmask) + C --> (X + (signmask ^ C))
927 if (C2->isSignMask())
928 return BinaryOperator::CreateAdd(X, ConstantInt::get(Ty, *C2 ^ *C));
929
930 // If X has no high-bits set above an xor mask:
931 // add (xor X, LowMaskC), C --> sub (LowMaskC + C), X
932 if (C2->isMask()) {
933 KnownBits LHSKnown = computeKnownBits(X, 0, &Add);
934 if ((*C2 | LHSKnown.Zero).isAllOnes())
935 return BinaryOperator::CreateSub(ConstantInt::get(Ty, *C2 + *C), X);
936 }
937
938 // Look for a math+logic pattern that corresponds to sext-in-register of a
939 // value with cleared high bits. Convert that into a pair of shifts:
940 // add (xor X, 0x80), 0xF..F80 --> (X << ShAmtC) >>s ShAmtC
941 // add (xor X, 0xF..F80), 0x80 --> (X << ShAmtC) >>s ShAmtC
942 if (Op0->hasOneUse() && *C2 == -(*C)) {
943 unsigned BitWidth = Ty->getScalarSizeInBits();
944 unsigned ShAmt = 0;
945 if (C->isPowerOf2())
946 ShAmt = BitWidth - C->logBase2() - 1;
947 else if (C2->isPowerOf2())
948 ShAmt = BitWidth - C2->logBase2() - 1;
950 0, &Add)) {
951 Constant *ShAmtC = ConstantInt::get(Ty, ShAmt);
952 Value *NewShl = Builder.CreateShl(X, ShAmtC, "sext");
953 return BinaryOperator::CreateAShr(NewShl, ShAmtC);
954 }
955 }
956 }
957
958 if (C->isOne() && Op0->hasOneUse()) {
959 // add (sext i1 X), 1 --> zext (not X)
960 // TODO: The smallest IR representation is (select X, 0, 1), and that would
961 // not require the one-use check. But we need to remove a transform in
962 // visitSelect and make sure that IR value tracking for select is equal or
963 // better than for these ops.
964 if (match(Op0, m_SExt(m_Value(X))) &&
965 X->getType()->getScalarSizeInBits() == 1)
966 return new ZExtInst(Builder.CreateNot(X), Ty);
967
968 // Shifts and add used to flip and mask off the low bit:
969 // add (ashr (shl i32 X, 31), 31), 1 --> and (not X), 1
970 const APInt *C3;
971 if (match(Op0, m_AShr(m_Shl(m_Value(X), m_APInt(C2)), m_APInt(C3))) &&
972 C2 == C3 && *C2 == Ty->getScalarSizeInBits() - 1) {
973 Value *NotX = Builder.CreateNot(X);
974 return BinaryOperator::CreateAnd(NotX, ConstantInt::get(Ty, 1));
975 }
976 }
977
978 // Fold (add (zext (add X, -1)), 1) -> (zext X) if X is non-zero.
979 // TODO: There's a general form for any constant on the outer add.
980 if (C->isOne()) {
981 if (match(Op0, m_ZExt(m_Add(m_Value(X), m_AllOnes())))) {
983 if (llvm::isKnownNonZero(X, DL, 0, Q.AC, Q.CxtI, Q.DT))
984 return new ZExtInst(X, Ty);
985 }
986 }
987
988 return nullptr;
989}
990
991// Matches multiplication expression Op * C where C is a constant. Returns the
992// constant value in C and the other operand in Op. Returns true if such a
993// match is found.
994static bool MatchMul(Value *E, Value *&Op, APInt &C) {
995 const APInt *AI;
996 if (match(E, m_Mul(m_Value(Op), m_APInt(AI)))) {
997 C = *AI;
998 return true;
999 }
1000 if (match(E, m_Shl(m_Value(Op), m_APInt(AI)))) {
1001 C = APInt(AI->getBitWidth(), 1);
1002 C <<= *AI;
1003 return true;
1004 }
1005 return false;
1006}
1007
1008// Matches remainder expression Op % C where C is a constant. Returns the
1009// constant value in C and the other operand in Op. Returns the signedness of
1010// the remainder operation in IsSigned. Returns true if such a match is
1011// found.
1012static bool MatchRem(Value *E, Value *&Op, APInt &C, bool &IsSigned) {
1013 const APInt *AI;
1014 IsSigned = false;
1015 if (match(E, m_SRem(m_Value(Op), m_APInt(AI)))) {
1016 IsSigned = true;
1017 C = *AI;
1018 return true;
1019 }
1020 if (match(E, m_URem(m_Value(Op), m_APInt(AI)))) {
1021 C = *AI;
1022 return true;
1023 }
1024 if (match(E, m_And(m_Value(Op), m_APInt(AI))) && (*AI + 1).isPowerOf2()) {
1025 C = *AI + 1;
1026 return true;
1027 }
1028 return false;
1029}
1030
1031// Matches division expression Op / C with the given signedness as indicated
1032// by IsSigned, where C is a constant. Returns the constant value in C and the
1033// other operand in Op. Returns true if such a match is found.
1034static bool MatchDiv(Value *E, Value *&Op, APInt &C, bool IsSigned) {
1035 const APInt *AI;
1036 if (IsSigned && match(E, m_SDiv(m_Value(Op), m_APInt(AI)))) {
1037 C = *AI;
1038 return true;
1039 }
1040 if (!IsSigned) {
1041 if (match(E, m_UDiv(m_Value(Op), m_APInt(AI)))) {
1042 C = *AI;
1043 return true;
1044 }
1045 if (match(E, m_LShr(m_Value(Op), m_APInt(AI)))) {
1046 C = APInt(AI->getBitWidth(), 1);
1047 C <<= *AI;
1048 return true;
1049 }
1050 }
1051 return false;
1052}
1053
1054// Returns whether C0 * C1 with the given signedness overflows.
1055static bool MulWillOverflow(APInt &C0, APInt &C1, bool IsSigned) {
1056 bool overflow;
1057 if (IsSigned)
1058 (void)C0.smul_ov(C1, overflow);
1059 else
1060 (void)C0.umul_ov(C1, overflow);
1061 return overflow;
1062}
1063
1064// Simplifies X % C0 + (( X / C0 ) % C1) * C0 to X % (C0 * C1), where (C0 * C1)
1065// does not overflow.
1067 Value *LHS = I.getOperand(0), *RHS = I.getOperand(1);
1068 Value *X, *MulOpV;
1069 APInt C0, MulOpC;
1070 bool IsSigned;
1071 // Match I = X % C0 + MulOpV * C0
1072 if (((MatchRem(LHS, X, C0, IsSigned) && MatchMul(RHS, MulOpV, MulOpC)) ||
1073 (MatchRem(RHS, X, C0, IsSigned) && MatchMul(LHS, MulOpV, MulOpC))) &&
1074 C0 == MulOpC) {
1075 Value *RemOpV;
1076 APInt C1;
1077 bool Rem2IsSigned;
1078 // Match MulOpC = RemOpV % C1
1079 if (MatchRem(MulOpV, RemOpV, C1, Rem2IsSigned) &&
1080 IsSigned == Rem2IsSigned) {
1081 Value *DivOpV;
1082 APInt DivOpC;
1083 // Match RemOpV = X / C0
1084 if (MatchDiv(RemOpV, DivOpV, DivOpC, IsSigned) && X == DivOpV &&
1085 C0 == DivOpC && !MulWillOverflow(C0, C1, IsSigned)) {
1086 Value *NewDivisor = ConstantInt::get(X->getType(), C0 * C1);
1087 return IsSigned ? Builder.CreateSRem(X, NewDivisor, "srem")
1088 : Builder.CreateURem(X, NewDivisor, "urem");
1089 }
1090 }
1091 }
1092
1093 return nullptr;
1094}
1095
1096/// Fold
1097/// (1 << NBits) - 1
1098/// Into:
1099/// ~(-(1 << NBits))
1100/// Because a 'not' is better for bit-tracking analysis and other transforms
1101/// than an 'add'. The new shl is always nsw, and is nuw if old `and` was.
1103 InstCombiner::BuilderTy &Builder) {
1104 Value *NBits;
1105 if (!match(&I, m_Add(m_OneUse(m_Shl(m_One(), m_Value(NBits))), m_AllOnes())))
1106 return nullptr;
1107
1108 Constant *MinusOne = Constant::getAllOnesValue(NBits->getType());
1109 Value *NotMask = Builder.CreateShl(MinusOne, NBits, "notmask");
1110 // Be wary of constant folding.
1111 if (auto *BOp = dyn_cast<BinaryOperator>(NotMask)) {
1112 // Always NSW. But NUW propagates from `add`.
1113 BOp->setHasNoSignedWrap();
1114 BOp->setHasNoUnsignedWrap(I.hasNoUnsignedWrap());
1115 }
1116
1117 return BinaryOperator::CreateNot(NotMask, I.getName());
1118}
1119
1121 assert(I.getOpcode() == Instruction::Add && "Expecting add instruction");
1122 Type *Ty = I.getType();
1123 auto getUAddSat = [&]() {
1124 return Intrinsic::getDeclaration(I.getModule(), Intrinsic::uadd_sat, Ty);
1125 };
1126
1127 // add (umin X, ~Y), Y --> uaddsat X, Y
1128 Value *X, *Y;
1130 m_Deferred(Y))))
1131 return CallInst::Create(getUAddSat(), { X, Y });
1132
1133 // add (umin X, ~C), C --> uaddsat X, C
1134 const APInt *C, *NotC;
1135 if (match(&I, m_Add(m_UMin(m_Value(X), m_APInt(NotC)), m_APInt(C))) &&
1136 *C == ~*NotC)
1137 return CallInst::Create(getUAddSat(), { X, ConstantInt::get(Ty, *C) });
1138
1139 return nullptr;
1140}
1141
1142/// Try to reduce signed division by power-of-2 to an arithmetic shift right.
1144 // Division must be by power-of-2, but not the minimum signed value.
1145 Value *X;
1146 const APInt *DivC;
1147 if (!match(Add.getOperand(0), m_SDiv(m_Value(X), m_Power2(DivC))) ||
1148 DivC->isNegative())
1149 return nullptr;
1150
1151 // Rounding is done by adding -1 if the dividend (X) is negative and has any
1152 // low bits set. The canonical pattern for that is an "ugt" compare with SMIN:
1153 // sext (icmp ugt (X & (DivC - 1)), SMIN)
1154 const APInt *MaskC;
1156 if (!match(Add.getOperand(1),
1157 m_SExt(m_ICmp(Pred, m_And(m_Specific(X), m_APInt(MaskC)),
1158 m_SignMask()))) ||
1159 Pred != ICmpInst::ICMP_UGT)
1160 return nullptr;
1161
1162 APInt SMin = APInt::getSignedMinValue(Add.getType()->getScalarSizeInBits());
1163 if (*MaskC != (SMin | (*DivC - 1)))
1164 return nullptr;
1165
1166 // (X / DivC) + sext ((X & (SMin | (DivC - 1)) >u SMin) --> X >>s log2(DivC)
1167 return BinaryOperator::CreateAShr(
1168 X, ConstantInt::get(Add.getType(), DivC->exactLogBase2()));
1169}
1170
1173 BinaryOperator &I) {
1174 assert((I.getOpcode() == Instruction::Add ||
1175 I.getOpcode() == Instruction::Or ||
1176 I.getOpcode() == Instruction::Sub) &&
1177 "Expecting add/or/sub instruction");
1178
1179 // We have a subtraction/addition between a (potentially truncated) *logical*
1180 // right-shift of X and a "select".
1181 Value *X, *Select;
1182 Instruction *LowBitsToSkip, *Extract;
1184 m_LShr(m_Value(X), m_Instruction(LowBitsToSkip)),
1185 m_Instruction(Extract))),
1186 m_Value(Select))))
1187 return nullptr;
1188
1189 // `add`/`or` is commutative; but for `sub`, "select" *must* be on RHS.
1190 if (I.getOpcode() == Instruction::Sub && I.getOperand(1) != Select)
1191 return nullptr;
1192
1193 Type *XTy = X->getType();
1194 bool HadTrunc = I.getType() != XTy;
1195
1196 // If there was a truncation of extracted value, then we'll need to produce
1197 // one extra instruction, so we need to ensure one instruction will go away.
1198 if (HadTrunc && !match(&I, m_c_BinOp(m_OneUse(m_Value()), m_Value())))
1199 return nullptr;
1200
1201 // Extraction should extract high NBits bits, with shift amount calculated as:
1202 // low bits to skip = shift bitwidth - high bits to extract
1203 // The shift amount itself may be extended, and we need to look past zero-ext
1204 // when matching NBits, that will matter for matching later.
1205 Constant *C;
1206 Value *NBits;
1207 if (!match(
1208 LowBitsToSkip,
1211 APInt(C->getType()->getScalarSizeInBits(),
1212 X->getType()->getScalarSizeInBits()))))
1213 return nullptr;
1214
1215 // Sign-extending value can be zero-extended if we `sub`tract it,
1216 // or sign-extended otherwise.
1217 auto SkipExtInMagic = [&I](Value *&V) {
1218 if (I.getOpcode() == Instruction::Sub)
1219 match(V, m_ZExtOrSelf(m_Value(V)));
1220 else
1221 match(V, m_SExtOrSelf(m_Value(V)));
1222 };
1223
1224 // Now, finally validate the sign-extending magic.
1225 // `select` itself may be appropriately extended, look past that.
1226 SkipExtInMagic(Select);
1227
1229 const APInt *Thr;
1230 Value *SignExtendingValue, *Zero;
1231 bool ShouldSignext;
1232 // It must be a select between two values we will later establish to be a
1233 // sign-extending value and a zero constant. The condition guarding the
1234 // sign-extension must be based on a sign bit of the same X we had in `lshr`.
1235 if (!match(Select, m_Select(m_ICmp(Pred, m_Specific(X), m_APInt(Thr)),
1236 m_Value(SignExtendingValue), m_Value(Zero))) ||
1237 !isSignBitCheck(Pred, *Thr, ShouldSignext))
1238 return nullptr;
1239
1240 // icmp-select pair is commutative.
1241 if (!ShouldSignext)
1242 std::swap(SignExtendingValue, Zero);
1243
1244 // If we should not perform sign-extension then we must add/or/subtract zero.
1245 if (!match(Zero, m_Zero()))
1246 return nullptr;
1247 // Otherwise, it should be some constant, left-shifted by the same NBits we
1248 // had in `lshr`. Said left-shift can also be appropriately extended.
1249 // Again, we must look past zero-ext when looking for NBits.
1250 SkipExtInMagic(SignExtendingValue);
1251 Constant *SignExtendingValueBaseConstant;
1252 if (!match(SignExtendingValue,
1253 m_Shl(m_Constant(SignExtendingValueBaseConstant),
1254 m_ZExtOrSelf(m_Specific(NBits)))))
1255 return nullptr;
1256 // If we `sub`, then the constant should be one, else it should be all-ones.
1257 if (I.getOpcode() == Instruction::Sub
1258 ? !match(SignExtendingValueBaseConstant, m_One())
1259 : !match(SignExtendingValueBaseConstant, m_AllOnes()))
1260 return nullptr;
1261
1262 auto *NewAShr = BinaryOperator::CreateAShr(X, LowBitsToSkip,
1263 Extract->getName() + ".sext");
1264 NewAShr->copyIRFlags(Extract); // Preserve `exact`-ness.
1265 if (!HadTrunc)
1266 return NewAShr;
1267
1268 Builder.Insert(NewAShr);
1269 return TruncInst::CreateTruncOrBitCast(NewAShr, I.getType());
1270}
1271
1272/// This is a specialization of a more general transform from
1273/// foldUsingDistributiveLaws. If that code can be made to work optimally
1274/// for multi-use cases or propagating nsw/nuw, then we would not need this.
1276 InstCombiner::BuilderTy &Builder) {
1277 // TODO: Also handle mul by doubling the shift amount?
1278 assert((I.getOpcode() == Instruction::Add ||
1279 I.getOpcode() == Instruction::Sub) &&
1280 "Expected add/sub");
1281 auto *Op0 = dyn_cast<BinaryOperator>(I.getOperand(0));
1282 auto *Op1 = dyn_cast<BinaryOperator>(I.getOperand(1));
1283 if (!Op0 || !Op1 || !(Op0->hasOneUse() || Op1->hasOneUse()))
1284 return nullptr;
1285
1286 Value *X, *Y, *ShAmt;
1287 if (!match(Op0, m_Shl(m_Value(X), m_Value(ShAmt))) ||
1288 !match(Op1, m_Shl(m_Value(Y), m_Specific(ShAmt))))
1289 return nullptr;
1290
1291 // No-wrap propagates only when all ops have no-wrap.
1292 bool HasNSW = I.hasNoSignedWrap() && Op0->hasNoSignedWrap() &&
1293 Op1->hasNoSignedWrap();
1294 bool HasNUW = I.hasNoUnsignedWrap() && Op0->hasNoUnsignedWrap() &&
1295 Op1->hasNoUnsignedWrap();
1296
1297 // add/sub (X << ShAmt), (Y << ShAmt) --> (add/sub X, Y) << ShAmt
1298 Value *NewMath = Builder.CreateBinOp(I.getOpcode(), X, Y);
1299 if (auto *NewI = dyn_cast<BinaryOperator>(NewMath)) {
1300 NewI->setHasNoSignedWrap(HasNSW);
1301 NewI->setHasNoUnsignedWrap(HasNUW);
1302 }
1303 auto *NewShl = BinaryOperator::CreateShl(NewMath, ShAmt);
1304 NewShl->setHasNoSignedWrap(HasNSW);
1305 NewShl->setHasNoUnsignedWrap(HasNUW);
1306 return NewShl;
1307}
1308
1309/// Reduce a sequence of masked half-width multiplies to a single multiply.
1310/// ((XLow * YHigh) + (YLow * XHigh)) << HalfBits) + (XLow * YLow) --> X * Y
1312 unsigned BitWidth = I.getType()->getScalarSizeInBits();
1313 // Skip the odd bitwidth types.
1314 if ((BitWidth & 0x1))
1315 return nullptr;
1316
1317 unsigned HalfBits = BitWidth >> 1;
1318 APInt HalfMask = APInt::getMaxValue(HalfBits);
1319
1320 // ResLo = (CrossSum << HalfBits) + (YLo * XLo)
1321 Value *XLo, *YLo;
1322 Value *CrossSum;
1323 if (!match(&I, m_c_Add(m_Shl(m_Value(CrossSum), m_SpecificInt(HalfBits)),
1324 m_Mul(m_Value(YLo), m_Value(XLo)))))
1325 return nullptr;
1326
1327 // XLo = X & HalfMask
1328 // YLo = Y & HalfMask
1329 // TODO: Refactor with SimplifyDemandedBits or KnownBits known leading zeros
1330 // to enhance robustness
1331 Value *X, *Y;
1332 if (!match(XLo, m_And(m_Value(X), m_SpecificInt(HalfMask))) ||
1333 !match(YLo, m_And(m_Value(Y), m_SpecificInt(HalfMask))))
1334 return nullptr;
1335
1336 // CrossSum = (X' * (Y >> Halfbits)) + (Y' * (X >> HalfBits))
1337 // X' can be either X or XLo in the pattern (and the same for Y')
1338 if (match(CrossSum,
1343 return BinaryOperator::CreateMul(X, Y);
1344
1345 return nullptr;
1346}
1347
1349 if (Value *V = simplifyAddInst(I.getOperand(0), I.getOperand(1),
1350 I.hasNoSignedWrap(), I.hasNoUnsignedWrap(),
1352 return replaceInstUsesWith(I, V);
1353
1355 return &I;
1356
1358 return X;
1359
1361 return Phi;
1362
1363 // (A*B)+(A*C) -> A*(B+C) etc
1365 return replaceInstUsesWith(I, V);
1366
1367 if (Instruction *R = foldBoxMultiply(I))
1368 return R;
1369
1371 return R;
1372
1374 return X;
1375
1377 return X;
1378
1379 Value *LHS = I.getOperand(0), *RHS = I.getOperand(1);
1380 Type *Ty = I.getType();
1381 if (Ty->isIntOrIntVectorTy(1))
1382 return BinaryOperator::CreateXor(LHS, RHS);
1383
1384 // X + X --> X << 1
1385 if (LHS == RHS) {
1386 auto *Shl = BinaryOperator::CreateShl(LHS, ConstantInt::get(Ty, 1));
1387 Shl->setHasNoSignedWrap(I.hasNoSignedWrap());
1388 Shl->setHasNoUnsignedWrap(I.hasNoUnsignedWrap());
1389 return Shl;
1390 }
1391
1392 Value *A, *B;
1393 if (match(LHS, m_Neg(m_Value(A)))) {
1394 // -A + -B --> -(A + B)
1395 if (match(RHS, m_Neg(m_Value(B))))
1397
1398 // -A + B --> B - A
1399 return BinaryOperator::CreateSub(RHS, A);
1400 }
1401
1402 // A + -B --> A - B
1403 if (match(RHS, m_Neg(m_Value(B))))
1404 return BinaryOperator::CreateSub(LHS, B);
1405
1407 return replaceInstUsesWith(I, V);
1408
1409 // (A + 1) + ~B --> A - B
1410 // ~B + (A + 1) --> A - B
1411 // (~B + A) + 1 --> A - B
1412 // (A + ~B) + 1 --> A - B
1413 if (match(&I, m_c_BinOp(m_Add(m_Value(A), m_One()), m_Not(m_Value(B)))) ||
1415 return BinaryOperator::CreateSub(A, B);
1416
1417 // (A + RHS) + RHS --> A + (RHS << 1)
1419 return BinaryOperator::CreateAdd(A, Builder.CreateShl(RHS, 1, "reass.add"));
1420
1421 // LHS + (A + LHS) --> A + (LHS << 1)
1423 return BinaryOperator::CreateAdd(A, Builder.CreateShl(LHS, 1, "reass.add"));
1424
1425 {
1426 // (A + C1) + (C2 - B) --> (A - B) + (C1 + C2)
1427 Constant *C1, *C2;
1428 if (match(&I, m_c_Add(m_Add(m_Value(A), m_ImmConstant(C1)),
1429 m_Sub(m_ImmConstant(C2), m_Value(B)))) &&
1430 (LHS->hasOneUse() || RHS->hasOneUse())) {
1431 Value *Sub = Builder.CreateSub(A, B);
1432 return BinaryOperator::CreateAdd(Sub, ConstantExpr::getAdd(C1, C2));
1433 }
1434
1435 // Canonicalize a constant sub operand as an add operand for better folding:
1436 // (C1 - A) + B --> (B - A) + C1
1438 m_Value(B)))) {
1439 Value *Sub = Builder.CreateSub(B, A, "reass.sub");
1440 return BinaryOperator::CreateAdd(Sub, C1);
1441 }
1442 }
1443
1444 // X % C0 + (( X / C0 ) % C1) * C0 => X % (C0 * C1)
1446
1447 // ((X s/ C1) << C2) + X => X s% -C1 where -C1 is 1 << C2
1448 const APInt *C1, *C2;
1449 if (match(LHS, m_Shl(m_SDiv(m_Specific(RHS), m_APInt(C1)), m_APInt(C2)))) {
1450 APInt one(C2->getBitWidth(), 1);
1451 APInt minusC1 = -(*C1);
1452 if (minusC1 == (one << *C2)) {
1453 Constant *NewRHS = ConstantInt::get(RHS->getType(), minusC1);
1454 return BinaryOperator::CreateSRem(RHS, NewRHS);
1455 }
1456 }
1457
1458 // (A & 2^C1) + A => A & (2^C1 - 1) iff bit C1 in A is a sign bit
1459 if (match(&I, m_c_Add(m_And(m_Value(A), m_APInt(C1)), m_Deferred(A))) &&
1460 C1->isPowerOf2() && (ComputeNumSignBits(A) > C1->countl_zero())) {
1461 Constant *NewMask = ConstantInt::get(RHS->getType(), *C1 - 1);
1462 return BinaryOperator::CreateAnd(A, NewMask);
1463 }
1464
1465 // ZExt (B - A) + ZExt(A) --> ZExt(B)
1466 if ((match(RHS, m_ZExt(m_Value(A))) &&
1468 (match(LHS, m_ZExt(m_Value(A))) &&
1470 return new ZExtInst(B, LHS->getType());
1471
1472 // A+B --> A|B iff A and B have no bits set in common.
1473 if (haveNoCommonBitsSet(LHS, RHS, DL, &AC, &I, &DT))
1474 return BinaryOperator::CreateOr(LHS, RHS);
1475
1476 if (Instruction *Ext = narrowMathIfNoOverflow(I))
1477 return Ext;
1478
1479 // (add (xor A, B) (and A, B)) --> (or A, B)
1480 // (add (and A, B) (xor A, B)) --> (or A, B)
1481 if (match(&I, m_c_BinOp(m_Xor(m_Value(A), m_Value(B)),
1483 return BinaryOperator::CreateOr(A, B);
1484
1485 // (add (or A, B) (and A, B)) --> (add A, B)
1486 // (add (and A, B) (or A, B)) --> (add A, B)
1487 if (match(&I, m_c_BinOp(m_Or(m_Value(A), m_Value(B)),
1489 // Replacing operands in-place to preserve nuw/nsw flags.
1490 replaceOperand(I, 0, A);
1491 replaceOperand(I, 1, B);
1492 return &I;
1493 }
1494
1495 // (add A (or A, -A)) --> (and (add A, -1) A)
1496 // (add A (or -A, A)) --> (and (add A, -1) A)
1497 // (add (or A, -A) A) --> (and (add A, -1) A)
1498 // (add (or -A, A) A) --> (and (add A, -1) A)
1500 m_Deferred(A)))))) {
1501 Value *Add =
1503 I.hasNoUnsignedWrap(), I.hasNoSignedWrap());
1504 return BinaryOperator::CreateAnd(Add, A);
1505 }
1506
1507 // Canonicalize ((A & -A) - 1) --> ((A - 1) & ~A)
1508 // Forms all commutable operations, and simplifies ctpop -> cttz folds.
1509 if (match(&I,
1511 m_AllOnes()))) {
1513 Value *Dec = Builder.CreateAdd(A, AllOnes);
1514 Value *Not = Builder.CreateXor(A, AllOnes);
1515 return BinaryOperator::CreateAnd(Dec, Not);
1516 }
1517
1518 // Disguised reassociation/factorization:
1519 // ~(A * C1) + A
1520 // ((A * -C1) - 1) + A
1521 // ((A * -C1) + A) - 1
1522 // (A * (1 - C1)) - 1
1523 if (match(&I,
1525 m_Deferred(A)))) {
1526 Type *Ty = I.getType();
1527 Constant *NewMulC = ConstantInt::get(Ty, 1 - *C1);
1528 Value *NewMul = Builder.CreateMul(A, NewMulC);
1529 return BinaryOperator::CreateAdd(NewMul, ConstantInt::getAllOnesValue(Ty));
1530 }
1531
1532 // (A * -2**C) + B --> B - (A << C)
1533 const APInt *NegPow2C;
1534 if (match(&I, m_c_Add(m_OneUse(m_Mul(m_Value(A), m_NegatedPower2(NegPow2C))),
1535 m_Value(B)))) {
1536 Constant *ShiftAmtC = ConstantInt::get(Ty, NegPow2C->countr_zero());
1537 Value *Shl = Builder.CreateShl(A, ShiftAmtC);
1538 return BinaryOperator::CreateSub(B, Shl);
1539 }
1540
1541 // Canonicalize signum variant that ends in add:
1542 // (A s>> (BW - 1)) + (zext (A s> 0)) --> (A s>> (BW - 1)) | (zext (A != 0))
1547 m_OneUse(m_ICmp(Pred, m_Specific(A), m_ZeroInt()))))) &&
1548 Pred == CmpInst::ICMP_SGT) {
1549 Value *NotZero = Builder.CreateIsNotNull(A, "isnotnull");
1550 Value *Zext = Builder.CreateZExt(NotZero, Ty, "isnotnull.zext");
1551 return BinaryOperator::CreateOr(LHS, Zext);
1552 }
1553
1554 if (Instruction *Ashr = foldAddToAshr(I))
1555 return Ashr;
1556
1557 // TODO(jingyue): Consider willNotOverflowSignedAdd and
1558 // willNotOverflowUnsignedAdd to reduce the number of invocations of
1559 // computeKnownBits.
1560 bool Changed = false;
1561 if (!I.hasNoSignedWrap() && willNotOverflowSignedAdd(LHS, RHS, I)) {
1562 Changed = true;
1563 I.setHasNoSignedWrap(true);
1564 }
1565 if (!I.hasNoUnsignedWrap() && willNotOverflowUnsignedAdd(LHS, RHS, I)) {
1566 Changed = true;
1567 I.setHasNoUnsignedWrap(true);
1568 }
1569
1571 return V;
1572
1573 if (Instruction *V =
1575 return V;
1576
1578 return SatAdd;
1579
1580 // usub.sat(A, B) + B => umax(A, B)
1581 if (match(&I, m_c_BinOp(
1582 m_OneUse(m_Intrinsic<Intrinsic::usub_sat>(m_Value(A), m_Value(B))),
1583 m_Deferred(B)))) {
1584 return replaceInstUsesWith(I,
1585 Builder.CreateIntrinsic(Intrinsic::umax, {I.getType()}, {A, B}));
1586 }
1587
1588 // ctpop(A) + ctpop(B) => ctpop(A | B) if A and B have no bits set in common.
1589 if (match(LHS, m_OneUse(m_Intrinsic<Intrinsic::ctpop>(m_Value(A)))) &&
1590 match(RHS, m_OneUse(m_Intrinsic<Intrinsic::ctpop>(m_Value(B)))) &&
1591 haveNoCommonBitsSet(A, B, DL, &AC, &I, &DT))
1592 return replaceInstUsesWith(
1593 I, Builder.CreateIntrinsic(Intrinsic::ctpop, {I.getType()},
1594 {Builder.CreateOr(A, B)}));
1595
1596 return Changed ? &I : nullptr;
1597}
1598
1599/// Eliminate an op from a linear interpolation (lerp) pattern.
1601 InstCombiner::BuilderTy &Builder) {
1602 Value *X, *Y, *Z;
1605 m_Value(Z))))),
1607 return nullptr;
1608
1609 // (Y * (1.0 - Z)) + (X * Z) --> Y + Z * (X - Y) [8 commuted variants]
1610 Value *XY = Builder.CreateFSubFMF(X, Y, &I);
1611 Value *MulZ = Builder.CreateFMulFMF(Z, XY, &I);
1612 return BinaryOperator::CreateFAddFMF(Y, MulZ, &I);
1613}
1614
1615/// Factor a common operand out of fadd/fsub of fmul/fdiv.
1617 InstCombiner::BuilderTy &Builder) {
1618 assert((I.getOpcode() == Instruction::FAdd ||
1619 I.getOpcode() == Instruction::FSub) && "Expecting fadd/fsub");
1620 assert(I.hasAllowReassoc() && I.hasNoSignedZeros() &&
1621 "FP factorization requires FMF");
1622
1623 if (Instruction *Lerp = factorizeLerp(I, Builder))
1624 return Lerp;
1625
1626 Value *Op0 = I.getOperand(0), *Op1 = I.getOperand(1);
1627 if (!Op0->hasOneUse() || !Op1->hasOneUse())
1628 return nullptr;
1629
1630 Value *X, *Y, *Z;
1631 bool IsFMul;
1632 if ((match(Op0, m_FMul(m_Value(X), m_Value(Z))) &&
1633 match(Op1, m_c_FMul(m_Value(Y), m_Specific(Z)))) ||
1634 (match(Op0, m_FMul(m_Value(Z), m_Value(X))) &&
1635 match(Op1, m_c_FMul(m_Value(Y), m_Specific(Z)))))
1636 IsFMul = true;
1637 else if (match(Op0, m_FDiv(m_Value(X), m_Value(Z))) &&
1638 match(Op1, m_FDiv(m_Value(Y), m_Specific(Z))))
1639 IsFMul = false;
1640 else
1641 return nullptr;
1642
1643 // (X * Z) + (Y * Z) --> (X + Y) * Z
1644 // (X * Z) - (Y * Z) --> (X - Y) * Z
1645 // (X / Z) + (Y / Z) --> (X + Y) / Z
1646 // (X / Z) - (Y / Z) --> (X - Y) / Z
1647 bool IsFAdd = I.getOpcode() == Instruction::FAdd;
1648 Value *XY = IsFAdd ? Builder.CreateFAddFMF(X, Y, &I)
1649 : Builder.CreateFSubFMF(X, Y, &I);
1650
1651 // Bail out if we just created a denormal constant.
1652 // TODO: This is copied from a previous implementation. Is it necessary?
1653 const APFloat *C;
1654 if (match(XY, m_APFloat(C)) && !C->isNormal())
1655 return nullptr;
1656
1657 return IsFMul ? BinaryOperator::CreateFMulFMF(XY, Z, &I)
1659}
1660
1662 if (Value *V = simplifyFAddInst(I.getOperand(0), I.getOperand(1),
1663 I.getFastMathFlags(),
1665 return replaceInstUsesWith(I, V);
1666
1668 return &I;
1669
1671 return X;
1672
1674 return Phi;
1675
1676 if (Instruction *FoldedFAdd = foldBinOpIntoSelectOrPhi(I))
1677 return FoldedFAdd;
1678
1679 // (-X) + Y --> Y - X
1680 Value *X, *Y;
1681 if (match(&I, m_c_FAdd(m_FNeg(m_Value(X)), m_Value(Y))))
1683
1684 // Similar to above, but look through fmul/fdiv for the negated term.
1685 // (-X * Y) + Z --> Z - (X * Y) [4 commuted variants]
1686 Value *Z;
1688 m_Value(Z)))) {
1689 Value *XY = Builder.CreateFMulFMF(X, Y, &I);
1690 return BinaryOperator::CreateFSubFMF(Z, XY, &I);
1691 }
1692 // (-X / Y) + Z --> Z - (X / Y) [2 commuted variants]
1693 // (X / -Y) + Z --> Z - (X / Y) [2 commuted variants]
1695 m_Value(Z))) ||
1697 m_Value(Z)))) {
1698 Value *XY = Builder.CreateFDivFMF(X, Y, &I);
1699 return BinaryOperator::CreateFSubFMF(Z, XY, &I);
1700 }
1701
1702 // Check for (fadd double (sitofp x), y), see if we can merge this into an
1703 // integer add followed by a promotion.
1704 Value *LHS = I.getOperand(0), *RHS = I.getOperand(1);
1705 if (SIToFPInst *LHSConv = dyn_cast<SIToFPInst>(LHS)) {
1706 Value *LHSIntVal = LHSConv->getOperand(0);
1707 Type *FPType = LHSConv->getType();
1708
1709 // TODO: This check is overly conservative. In many cases known bits
1710 // analysis can tell us that the result of the addition has less significant
1711 // bits than the integer type can hold.
1712 auto IsValidPromotion = [](Type *FTy, Type *ITy) {
1713 Type *FScalarTy = FTy->getScalarType();
1714 Type *IScalarTy = ITy->getScalarType();
1715
1716 // Do we have enough bits in the significand to represent the result of
1717 // the integer addition?
1718 unsigned MaxRepresentableBits =
1720 return IScalarTy->getIntegerBitWidth() <= MaxRepresentableBits;
1721 };
1722
1723 // (fadd double (sitofp x), fpcst) --> (sitofp (add int x, intcst))
1724 // ... if the constant fits in the integer value. This is useful for things
1725 // like (double)(x & 1234) + 4.0 -> (double)((X & 1234)+4) which no longer
1726 // requires a constant pool load, and generally allows the add to be better
1727 // instcombined.
1728 if (ConstantFP *CFP = dyn_cast<ConstantFP>(RHS))
1729 if (IsValidPromotion(FPType, LHSIntVal->getType())) {
1730 Constant *CI =
1731 ConstantExpr::getFPToSI(CFP, LHSIntVal->getType());
1732 if (LHSConv->hasOneUse() &&
1733 ConstantExpr::getSIToFP(CI, I.getType()) == CFP &&
1734 willNotOverflowSignedAdd(LHSIntVal, CI, I)) {
1735 // Insert the new integer add.
1736 Value *NewAdd = Builder.CreateNSWAdd(LHSIntVal, CI, "addconv");
1737 return new SIToFPInst(NewAdd, I.getType());
1738 }
1739 }
1740
1741 // (fadd double (sitofp x), (sitofp y)) --> (sitofp (add int x, y))
1742 if (SIToFPInst *RHSConv = dyn_cast<SIToFPInst>(RHS)) {
1743 Value *RHSIntVal = RHSConv->getOperand(0);
1744 // It's enough to check LHS types only because we require int types to
1745 // be the same for this transform.
1746 if (IsValidPromotion(FPType, LHSIntVal->getType())) {
1747 // Only do this if x/y have the same type, if at least one of them has a
1748 // single use (so we don't increase the number of int->fp conversions),
1749 // and if the integer add will not overflow.
1750 if (LHSIntVal->getType() == RHSIntVal->getType() &&
1751 (LHSConv->hasOneUse() || RHSConv->hasOneUse()) &&
1752 willNotOverflowSignedAdd(LHSIntVal, RHSIntVal, I)) {
1753 // Insert the new integer add.
1754 Value *NewAdd = Builder.CreateNSWAdd(LHSIntVal, RHSIntVal, "addconv");
1755 return new SIToFPInst(NewAdd, I.getType());
1756 }
1757 }
1758 }
1759 }
1760
1761 // Handle specials cases for FAdd with selects feeding the operation
1763 return replaceInstUsesWith(I, V);
1764
1765 if (I.hasAllowReassoc() && I.hasNoSignedZeros()) {
1767 return F;
1768
1769 // Try to fold fadd into start value of reduction intrinsic.
1770 if (match(&I, m_c_FAdd(m_OneUse(m_Intrinsic<Intrinsic::vector_reduce_fadd>(
1771 m_AnyZeroFP(), m_Value(X))),
1772 m_Value(Y)))) {
1773 // fadd (rdx 0.0, X), Y --> rdx Y, X
1774 return replaceInstUsesWith(
1775 I, Builder.CreateIntrinsic(Intrinsic::vector_reduce_fadd,
1776 {X->getType()}, {Y, X}, &I));
1777 }
1778 const APFloat *StartC, *C;
1779 if (match(LHS, m_OneUse(m_Intrinsic<Intrinsic::vector_reduce_fadd>(
1780 m_APFloat(StartC), m_Value(X)))) &&
1781 match(RHS, m_APFloat(C))) {
1782 // fadd (rdx StartC, X), C --> rdx (C + StartC), X
1783 Constant *NewStartC = ConstantFP::get(I.getType(), *C + *StartC);
1784 return replaceInstUsesWith(
1785 I, Builder.CreateIntrinsic(Intrinsic::vector_reduce_fadd,
1786 {X->getType()}, {NewStartC, X}, &I));
1787 }
1788
1789 // (X * MulC) + X --> X * (MulC + 1.0)
1790 Constant *MulC;
1791 if (match(&I, m_c_FAdd(m_FMul(m_Value(X), m_ImmConstant(MulC)),
1792 m_Deferred(X)))) {
1794 Instruction::FAdd, MulC, ConstantFP::get(I.getType(), 1.0), DL))
1795 return BinaryOperator::CreateFMulFMF(X, NewMulC, &I);
1796 }
1797
1798 // (-X - Y) + (X + Z) --> Z - Y
1800 m_c_FAdd(m_Deferred(X), m_Value(Z)))))
1801 return BinaryOperator::CreateFSubFMF(Z, Y, &I);
1802
1803 if (Value *V = FAddCombine(Builder).simplify(&I))
1804 return replaceInstUsesWith(I, V);
1805 }
1806
1807 return nullptr;
1808}
1809
1810/// Optimize pointer differences into the same array into a size. Consider:
1811/// &A[10] - &A[0]: we should compile this to "10". LHS/RHS are the pointer
1812/// operands to the ptrtoint instructions for the LHS/RHS of the subtract.
1814 Type *Ty, bool IsNUW) {
1815 // If LHS is a gep based on RHS or RHS is a gep based on LHS, we can optimize
1816 // this.
1817 bool Swapped = false;
1818 GEPOperator *GEP1 = nullptr, *GEP2 = nullptr;
1819 if (!isa<GEPOperator>(LHS) && isa<GEPOperator>(RHS)) {
1820 std::swap(LHS, RHS);
1821 Swapped = true;
1822 }
1823
1824 // Require at least one GEP with a common base pointer on both sides.
1825 if (auto *LHSGEP = dyn_cast<GEPOperator>(LHS)) {
1826 // (gep X, ...) - X
1827 if (LHSGEP->getOperand(0)->stripPointerCasts() ==
1829 GEP1 = LHSGEP;
1830 } else if (auto *RHSGEP = dyn_cast<GEPOperator>(RHS)) {
1831 // (gep X, ...) - (gep X, ...)
1832 if (LHSGEP->getOperand(0)->stripPointerCasts() ==
1833 RHSGEP->getOperand(0)->stripPointerCasts()) {
1834 GEP1 = LHSGEP;
1835 GEP2 = RHSGEP;
1836 }
1837 }
1838 }
1839
1840 if (!GEP1)
1841 return nullptr;
1842
1843 if (GEP2) {
1844 // (gep X, ...) - (gep X, ...)
1845 //
1846 // Avoid duplicating the arithmetic if there are more than one non-constant
1847 // indices between the two GEPs and either GEP has a non-constant index and
1848 // multiple users. If zero non-constant index, the result is a constant and
1849 // there is no duplication. If one non-constant index, the result is an add
1850 // or sub with a constant, which is no larger than the original code, and
1851 // there's no duplicated arithmetic, even if either GEP has multiple
1852 // users. If more than one non-constant indices combined, as long as the GEP
1853 // with at least one non-constant index doesn't have multiple users, there
1854 // is no duplication.
1855 unsigned NumNonConstantIndices1 = GEP1->countNonConstantIndices();
1856 unsigned NumNonConstantIndices2 = GEP2->countNonConstantIndices();
1857 if (NumNonConstantIndices1 + NumNonConstantIndices2 > 1 &&
1858 ((NumNonConstantIndices1 > 0 && !GEP1->hasOneUse()) ||
1859 (NumNonConstantIndices2 > 0 && !GEP2->hasOneUse()))) {
1860 return nullptr;
1861 }
1862 }
1863
1864 // Emit the offset of the GEP and an intptr_t.
1865 Value *Result = EmitGEPOffset(GEP1);
1866
1867 // If this is a single inbounds GEP and the original sub was nuw,
1868 // then the final multiplication is also nuw.
1869 if (auto *I = dyn_cast<Instruction>(Result))
1870 if (IsNUW && !GEP2 && !Swapped && GEP1->isInBounds() &&
1871 I->getOpcode() == Instruction::Mul)
1872 I->setHasNoUnsignedWrap();
1873
1874 // If we have a 2nd GEP of the same base pointer, subtract the offsets.
1875 // If both GEPs are inbounds, then the subtract does not have signed overflow.
1876 if (GEP2) {
1877 Value *Offset = EmitGEPOffset(GEP2);
1878 Result = Builder.CreateSub(Result, Offset, "gepdiff", /* NUW */ false,
1879 GEP1->isInBounds() && GEP2->isInBounds());
1880 }
1881
1882 // If we have p - gep(p, ...) then we have to negate the result.
1883 if (Swapped)
1884 Result = Builder.CreateNeg(Result, "diff.neg");
1885
1886 return Builder.CreateIntCast(Result, Ty, true);
1887}
1888
1890 InstCombiner::BuilderTy &Builder) {
1891 Value *Op0 = I.getOperand(0);
1892 Value *Op1 = I.getOperand(1);
1893 Type *Ty = I.getType();
1894 auto *MinMax = dyn_cast<MinMaxIntrinsic>(Op1);
1895 if (!MinMax)
1896 return nullptr;
1897
1898 // sub(add(X,Y), s/umin(X,Y)) --> s/umax(X,Y)
1899 // sub(add(X,Y), s/umax(X,Y)) --> s/umin(X,Y)
1900 Value *X = MinMax->getLHS();
1901 Value *Y = MinMax->getRHS();
1902 if (match(Op0, m_c_Add(m_Specific(X), m_Specific(Y))) &&
1903 (Op0->hasOneUse() || Op1->hasOneUse())) {
1904 Intrinsic::ID InvID = getInverseMinMaxIntrinsic(MinMax->getIntrinsicID());
1905 Function *F = Intrinsic::getDeclaration(I.getModule(), InvID, Ty);
1906 return CallInst::Create(F, {X, Y});
1907 }
1908
1909 // sub(add(X,Y),umin(Y,Z)) --> add(X,usub.sat(Y,Z))
1910 // sub(add(X,Z),umin(Y,Z)) --> add(X,usub.sat(Z,Y))
1911 Value *Z;
1912 if (match(Op1, m_OneUse(m_UMin(m_Value(Y), m_Value(Z))))) {
1913 if (match(Op0, m_OneUse(m_c_Add(m_Specific(Y), m_Value(X))))) {
1914 Value *USub = Builder.CreateIntrinsic(Intrinsic::usub_sat, Ty, {Y, Z});
1915 return BinaryOperator::CreateAdd(X, USub);
1916 }
1917 if (match(Op0, m_OneUse(m_c_Add(m_Specific(Z), m_Value(X))))) {
1918 Value *USub = Builder.CreateIntrinsic(Intrinsic::usub_sat, Ty, {Z, Y});
1919 return BinaryOperator::CreateAdd(X, USub);
1920 }
1921 }
1922
1923 // sub Op0, smin((sub nsw Op0, Z), 0) --> smax Op0, Z
1924 // sub Op0, smax((sub nsw Op0, Z), 0) --> smin Op0, Z
1925 if (MinMax->isSigned() && match(Y, m_ZeroInt()) &&
1926 match(X, m_NSWSub(m_Specific(Op0), m_Value(Z)))) {
1927 Intrinsic::ID InvID = getInverseMinMaxIntrinsic(MinMax->getIntrinsicID());
1928 Function *F = Intrinsic::getDeclaration(I.getModule(), InvID, Ty);
1929 return CallInst::Create(F, {Op0, Z});
1930 }
1931
1932 return nullptr;
1933}
1934
1936 if (Value *V = simplifySubInst(I.getOperand(0), I.getOperand(1),
1937 I.hasNoSignedWrap(), I.hasNoUnsignedWrap(),
1939 return replaceInstUsesWith(I, V);
1940
1942 return X;
1943
1945 return Phi;
1946
1947 Value *Op0 = I.getOperand(0), *Op1 = I.getOperand(1);
1948
1949 // If this is a 'B = x-(-A)', change to B = x+A.
1950 // We deal with this without involving Negator to preserve NSW flag.
1951 if (Value *V = dyn_castNegVal(Op1)) {
1952 BinaryOperator *Res = BinaryOperator::CreateAdd(Op0, V);
1953
1954 if (const auto *BO = dyn_cast<BinaryOperator>(Op1)) {
1955 assert(BO->getOpcode() == Instruction::Sub &&
1956 "Expected a subtraction operator!");
1957 if (BO->hasNoSignedWrap() && I.hasNoSignedWrap())
1958 Res->setHasNoSignedWrap(true);
1959 } else {
1960 if (cast<Constant>(Op1)->isNotMinSignedValue() && I.hasNoSignedWrap())
1961 Res->setHasNoSignedWrap(true);
1962 }
1963
1964 return Res;
1965 }
1966
1967 // Try this before Negator to preserve NSW flag.
1969 return R;
1970
1971 Constant *C;
1972 if (match(Op0, m_ImmConstant(C))) {
1973 Value *X;
1974 Constant *C2;
1975
1976 // C-(X+C2) --> (C-C2)-X
1977 if (match(Op1, m_Add(m_Value(X), m_ImmConstant(C2))))
1978 return BinaryOperator::CreateSub(ConstantExpr::getSub(C, C2), X);
1979 }
1980
1981 auto TryToNarrowDeduceFlags = [this, &I, &Op0, &Op1]() -> Instruction * {
1982 if (Instruction *Ext = narrowMathIfNoOverflow(I))
1983 return Ext;
1984
1985 bool Changed = false;
1986 if (!I.hasNoSignedWrap() && willNotOverflowSignedSub(Op0, Op1, I)) {
1987 Changed = true;
1988 I.setHasNoSignedWrap(true);
1989 }
1990 if (!I.hasNoUnsignedWrap() && willNotOverflowUnsignedSub(Op0, Op1, I)) {
1991 Changed = true;
1992 I.setHasNoUnsignedWrap(true);
1993 }
1994
1995 return Changed ? &I : nullptr;
1996 };
1997
1998 // First, let's try to interpret `sub a, b` as `add a, (sub 0, b)`,
1999 // and let's try to sink `(sub 0, b)` into `b` itself. But only if this isn't
2000 // a pure negation used by a select that looks like abs/nabs.
2001 bool IsNegation = match(Op0, m_ZeroInt());
2002 if (!IsNegation || none_of(I.users(), [&I, Op1](const User *U) {
2003 const Instruction *UI = dyn_cast<Instruction>(U);
2004 if (!UI)
2005 return false;
2006 return match(UI,
2007 m_Select(m_Value(), m_Specific(Op1), m_Specific(&I))) ||
2008 match(UI, m_Select(m_Value(), m_Specific(&I), m_Specific(Op1)));
2009 })) {
2010 if (Value *NegOp1 = Negator::Negate(IsNegation, Op1, *this))
2011 return BinaryOperator::CreateAdd(NegOp1, Op0);
2012 }
2013 if (IsNegation)
2014 return TryToNarrowDeduceFlags(); // Should have been handled in Negator!
2015
2016 // (A*B)-(A*C) -> A*(B-C) etc
2018 return replaceInstUsesWith(I, V);
2019
2020 if (I.getType()->isIntOrIntVectorTy(1))
2021 return BinaryOperator::CreateXor(Op0, Op1);
2022
2023 // Replace (-1 - A) with (~A).
2024 if (match(Op0, m_AllOnes()))
2025 return BinaryOperator::CreateNot(Op1);
2026
2027 // (X + -1) - Y --> ~Y + X
2028 Value *X, *Y;
2029 if (match(Op0, m_OneUse(m_Add(m_Value(X), m_AllOnes()))))
2030 return BinaryOperator::CreateAdd(Builder.CreateNot(Op1), X);
2031
2032 // Reassociate sub/add sequences to create more add instructions and
2033 // reduce dependency chains:
2034 // ((X - Y) + Z) - Op1 --> (X + Z) - (Y + Op1)
2035 Value *Z;
2037 m_Value(Z))))) {
2038 Value *XZ = Builder.CreateAdd(X, Z);
2039 Value *YW = Builder.CreateAdd(Y, Op1);
2040 return BinaryOperator::CreateSub(XZ, YW);
2041 }
2042
2043 // ((X - Y) - Op1) --> X - (Y + Op1)
2044 if (match(Op0, m_OneUse(m_Sub(m_Value(X), m_Value(Y))))) {
2045 Value *Add = Builder.CreateAdd(Y, Op1);
2046 return BinaryOperator::CreateSub(X, Add);
2047 }
2048
2049 // (~X) - (~Y) --> Y - X
2050 // This is placed after the other reassociations and explicitly excludes a
2051 // sub-of-sub pattern to avoid infinite looping.
2052 if (isFreeToInvert(Op0, Op0->hasOneUse()) &&
2053 isFreeToInvert(Op1, Op1->hasOneUse()) &&
2054 !match(Op0, m_Sub(m_ImmConstant(), m_Value()))) {
2055 Value *NotOp0 = Builder.CreateNot(Op0);
2056 Value *NotOp1 = Builder.CreateNot(Op1);
2057 return BinaryOperator::CreateSub(NotOp1, NotOp0);
2058 }
2059
2060 auto m_AddRdx = [](Value *&Vec) {
2061 return m_OneUse(m_Intrinsic<Intrinsic::vector_reduce_add>(m_Value(Vec)));
2062 };
2063 Value *V0, *V1;
2064 if (match(Op0, m_AddRdx(V0)) && match(Op1, m_AddRdx(V1)) &&
2065 V0->getType() == V1->getType()) {
2066 // Difference of sums is sum of differences:
2067 // add_rdx(V0) - add_rdx(V1) --> add_rdx(V0 - V1)
2068 Value *Sub = Builder.CreateSub(V0, V1);
2069 Value *Rdx = Builder.CreateIntrinsic(Intrinsic::vector_reduce_add,
2070 {Sub->getType()}, {Sub});
2071 return replaceInstUsesWith(I, Rdx);
2072 }
2073
2074 if (Constant *C = dyn_cast<Constant>(Op0)) {
2075 Value *X;
2076 if (match(Op1, m_ZExt(m_Value(X))) && X->getType()->isIntOrIntVectorTy(1))
2077 // C - (zext bool) --> bool ? C - 1 : C
2079 if (match(Op1, m_SExt(m_Value(X))) && X->getType()->isIntOrIntVectorTy(1))
2080 // C - (sext bool) --> bool ? C + 1 : C
2082
2083 // C - ~X == X + (1+C)
2084 if (match(Op1, m_Not(m_Value(X))))
2085 return BinaryOperator::CreateAdd(X, InstCombiner::AddOne(C));
2086
2087 // Try to fold constant sub into select arguments.
2088 if (SelectInst *SI = dyn_cast<SelectInst>(Op1))
2089 if (Instruction *R = FoldOpIntoSelect(I, SI))
2090 return R;
2091
2092 // Try to fold constant sub into PHI values.
2093 if (PHINode *PN = dyn_cast<PHINode>(Op1))
2094 if (Instruction *R = foldOpIntoPhi(I, PN))
2095 return R;
2096
2097 Constant *C2;
2098
2099 // C-(C2-X) --> X+(C-C2)
2100 if (match(Op1, m_Sub(m_ImmConstant(C2), m_Value(X))))
2101 return BinaryOperator::CreateAdd(X, ConstantExpr::getSub(C, C2));
2102 }
2103
2104 const APInt *Op0C;
2105 if (match(Op0, m_APInt(Op0C))) {
2106 if (Op0C->isMask()) {
2107 // Turn this into a xor if LHS is 2^n-1 and the remaining bits are known
2108 // zero.
2109 KnownBits RHSKnown = computeKnownBits(Op1, 0, &I);
2110 if ((*Op0C | RHSKnown.Zero).isAllOnes())
2111 return BinaryOperator::CreateXor(Op1, Op0);
2112 }
2113
2114 // C - ((C3 -nuw X) & C2) --> (C - (C2 & C3)) + (X & C2) when:
2115 // (C3 - ((C2 & C3) - 1)) is pow2
2116 // ((C2 + C3) & ((C2 & C3) - 1)) == ((C2 & C3) - 1)
2117 // C2 is negative pow2 || sub nuw
2118 const APInt *C2, *C3;
2119 BinaryOperator *InnerSub;
2120 if (match(Op1, m_OneUse(m_And(m_BinOp(InnerSub), m_APInt(C2)))) &&
2121 match(InnerSub, m_Sub(m_APInt(C3), m_Value(X))) &&
2122 (InnerSub->hasNoUnsignedWrap() || C2->isNegatedPowerOf2())) {
2123 APInt C2AndC3 = *C2 & *C3;
2124 APInt C2AndC3Minus1 = C2AndC3 - 1;
2125 APInt C2AddC3 = *C2 + *C3;
2126 if ((*C3 - C2AndC3Minus1).isPowerOf2() &&
2127 C2AndC3Minus1.isSubsetOf(C2AddC3)) {
2128 Value *And = Builder.CreateAnd(X, ConstantInt::get(I.getType(), *C2));
2129 return BinaryOperator::CreateAdd(
2130 And, ConstantInt::get(I.getType(), *Op0C - C2AndC3));
2131 }
2132 }
2133 }
2134
2135 {
2136 Value *Y;
2137 // X-(X+Y) == -Y X-(Y+X) == -Y
2138 if (match(Op1, m_c_Add(m_Specific(Op0), m_Value(Y))))
2140
2141 // (X-Y)-X == -Y
2142 if (match(Op0, m_Sub(m_Specific(Op1), m_Value(Y))))
2144 }
2145
2146 // (sub (or A, B) (and A, B)) --> (xor A, B)
2147 {
2148 Value *A, *B;
2149 if (match(Op1, m_And(m_Value(A), m_Value(B))) &&
2150 match(Op0, m_c_Or(m_Specific(A), m_Specific(B))))
2151 return BinaryOperator::CreateXor(A, B);
2152 }
2153
2154 // (sub (add A, B) (or A, B)) --> (and A, B)
2155 {
2156 Value *A, *B;
2157 if (match(Op0, m_Add(m_Value(A), m_Value(B))) &&
2158 match(Op1, m_c_Or(m_Specific(A), m_Specific(B))))
2159 return BinaryOperator::CreateAnd(A, B);
2160 }
2161
2162 // (sub (add A, B) (and A, B)) --> (or A, B)
2163 {
2164 Value *A, *B;
2165 if (match(Op0, m_Add(m_Value(A), m_Value(B))) &&
2167 return BinaryOperator::CreateOr(A, B);
2168 }
2169
2170 // (sub (and A, B) (or A, B)) --> neg (xor A, B)
2171 {
2172 Value *A, *B;
2173 if (match(Op0, m_And(m_Value(A), m_Value(B))) &&
2174 match(Op1, m_c_Or(m_Specific(A), m_Specific(B))) &&
2175 (Op0->hasOneUse() || Op1->hasOneUse()))
2177 }
2178
2179 // (sub (or A, B), (xor A, B)) --> (and A, B)
2180 {
2181 Value *A, *B;
2182 if (match(Op1, m_Xor(m_Value(A), m_Value(B))) &&
2183 match(Op0, m_c_Or(m_Specific(A), m_Specific(B))))
2184 return BinaryOperator::CreateAnd(A, B);
2185 }
2186
2187 // (sub (xor A, B) (or A, B)) --> neg (and A, B)
2188 {
2189 Value *A, *B;
2190 if (match(Op0, m_Xor(m_Value(A), m_Value(B))) &&
2191 match(Op1, m_c_Or(m_Specific(A), m_Specific(B))) &&
2192 (Op0->hasOneUse() || Op1->hasOneUse()))
2194 }
2195
2196 {
2197 Value *Y;
2198 // ((X | Y) - X) --> (~X & Y)
2199 if (match(Op0, m_OneUse(m_c_Or(m_Value(Y), m_Specific(Op1)))))
2200 return BinaryOperator::CreateAnd(
2201 Y, Builder.CreateNot(Op1, Op1->getName() + ".not"));
2202 }
2203
2204 {
2205 // (sub (and Op1, (neg X)), Op1) --> neg (and Op1, (add X, -1))
2206 Value *X;
2207 if (match(Op0, m_OneUse(m_c_And(m_Specific(Op1),
2208 m_OneUse(m_Neg(m_Value(X))))))) {
2210 Op1, Builder.CreateAdd(X, Constant::getAllOnesValue(I.getType()))));
2211 }
2212 }
2213
2214 {
2215 // (sub (and Op1, C), Op1) --> neg (and Op1, ~C)
2216 Constant *C;
2217 if (match(Op0, m_OneUse(m_And(m_Specific(Op1), m_Constant(C))))) {
2220 }
2221 }
2222
2224 return R;
2225
2226 {
2227 // If we have a subtraction between some value and a select between
2228 // said value and something else, sink subtraction into select hands, i.e.:
2229 // sub (select %Cond, %TrueVal, %FalseVal), %Op1
2230 // ->
2231 // select %Cond, (sub %TrueVal, %Op1), (sub %FalseVal, %Op1)
2232 // or
2233 // sub %Op0, (select %Cond, %TrueVal, %FalseVal)
2234 // ->
2235 // select %Cond, (sub %Op0, %TrueVal), (sub %Op0, %FalseVal)
2236 // This will result in select between new subtraction and 0.
2237 auto SinkSubIntoSelect =
2238 [Ty = I.getType()](Value *Select, Value *OtherHandOfSub,
2239 auto SubBuilder) -> Instruction * {
2240 Value *Cond, *TrueVal, *FalseVal;
2241 if (!match(Select, m_OneUse(m_Select(m_Value(Cond), m_Value(TrueVal),
2242 m_Value(FalseVal)))))
2243 return nullptr;
2244 if (OtherHandOfSub != TrueVal && OtherHandOfSub != FalseVal)
2245 return nullptr;
2246 // While it is really tempting to just create two subtractions and let
2247 // InstCombine fold one of those to 0, it isn't possible to do so
2248 // because of worklist visitation order. So ugly it is.
2249 bool OtherHandOfSubIsTrueVal = OtherHandOfSub == TrueVal;
2250 Value *NewSub = SubBuilder(OtherHandOfSubIsTrueVal ? FalseVal : TrueVal);
2251 Constant *Zero = Constant::getNullValue(Ty);
2252 SelectInst *NewSel =
2253 SelectInst::Create(Cond, OtherHandOfSubIsTrueVal ? Zero : NewSub,
2254 OtherHandOfSubIsTrueVal ? NewSub : Zero);
2255 // Preserve prof metadata if any.
2256 NewSel->copyMetadata(cast<Instruction>(*Select));
2257 return NewSel;
2258 };
2259 if (Instruction *NewSel = SinkSubIntoSelect(
2260 /*Select=*/Op0, /*OtherHandOfSub=*/Op1,
2261 [Builder = &Builder, Op1](Value *OtherHandOfSelect) {
2262 return Builder->CreateSub(OtherHandOfSelect,
2263 /*OtherHandOfSub=*/Op1);
2264 }))
2265 return NewSel;
2266 if (Instruction *NewSel = SinkSubIntoSelect(
2267 /*Select=*/Op1, /*OtherHandOfSub=*/Op0,
2268 [Builder = &Builder, Op0](Value *OtherHandOfSelect) {
2269 return Builder->CreateSub(/*OtherHandOfSub=*/Op0,
2270 OtherHandOfSelect);
2271 }))
2272 return NewSel;
2273 }
2274
2275 // (X - (X & Y)) --> (X & ~Y)
2276 if (match(Op1, m_c_And(m_Specific(Op0), m_Value(Y))) &&
2277 (Op1->hasOneUse() || isa<Constant>(Y)))
2278 return BinaryOperator::CreateAnd(
2279 Op0, Builder.CreateNot(Y, Y->getName() + ".not"));
2280
2281 // ~X - Min/Max(~X, Y) -> ~Min/Max(X, ~Y) - X
2282 // ~X - Min/Max(Y, ~X) -> ~Min/Max(X, ~Y) - X
2283 // Min/Max(~X, Y) - ~X -> X - ~Min/Max(X, ~Y)
2284 // Min/Max(Y, ~X) - ~X -> X - ~Min/Max(X, ~Y)
2285 // As long as Y is freely invertible, this will be neutral or a win.
2286 // Note: We don't generate the inverse max/min, just create the 'not' of
2287 // it and let other folds do the rest.
2288 if (match(Op0, m_Not(m_Value(X))) &&
2289 match(Op1, m_c_MaxOrMin(m_Specific(Op0), m_Value(Y))) &&
2290 !Op0->hasNUsesOrMore(3) && isFreeToInvert(Y, Y->hasOneUse())) {
2291 Value *Not = Builder.CreateNot(Op1);
2292 return BinaryOperator::CreateSub(Not, X);
2293 }
2294 if (match(Op1, m_Not(m_Value(X))) &&
2295 match(Op0, m_c_MaxOrMin(m_Specific(Op1), m_Value(Y))) &&
2296 !Op1->hasNUsesOrMore(3) && isFreeToInvert(Y, Y->hasOneUse())) {
2297 Value *Not = Builder.CreateNot(Op0);
2298 return BinaryOperator::CreateSub(X, Not);
2299 }
2300
2301 // Optimize pointer differences into the same array into a size. Consider:
2302 // &A[10] - &A[0]: we should compile this to "10".
2303 Value *LHSOp, *RHSOp;
2304 if (match(Op0, m_PtrToInt(m_Value(LHSOp))) &&
2305 match(Op1, m_PtrToInt(m_Value(RHSOp))))
2306 if (Value *Res = OptimizePointerDifference(LHSOp, RHSOp, I.getType(),
2307 I.hasNoUnsignedWrap()))
2308 return replaceInstUsesWith(I, Res);
2309
2310 // trunc(p)-trunc(q) -> trunc(p-q)
2311 if (match(Op0, m_Trunc(m_PtrToInt(m_Value(LHSOp)))) &&
2312 match(Op1, m_Trunc(m_PtrToInt(m_Value(RHSOp)))))
2313 if (Value *Res = OptimizePointerDifference(LHSOp, RHSOp, I.getType(),
2314 /* IsNUW */ false))
2315 return replaceInstUsesWith(I, Res);
2316
2317 // Canonicalize a shifty way to code absolute value to the common pattern.
2318 // There are 2 potential commuted variants.
2319 // We're relying on the fact that we only do this transform when the shift has
2320 // exactly 2 uses and the xor has exactly 1 use (otherwise, we might increase
2321 // instructions).
2322 Value *A;
2323 const APInt *ShAmt;
2324 Type *Ty = I.getType();
2325 unsigned BitWidth = Ty->getScalarSizeInBits();
2326 if (match(Op1, m_AShr(m_Value(A), m_APInt(ShAmt))) &&
2327 Op1->hasNUses(2) && *ShAmt == BitWidth - 1 &&
2328 match(Op0, m_OneUse(m_c_Xor(m_Specific(A), m_Specific(Op1))))) {
2329 // B = ashr i32 A, 31 ; smear the sign bit
2330 // sub (xor A, B), B ; flip bits if negative and subtract -1 (add 1)
2331 // --> (A < 0) ? -A : A
2332 Value *IsNeg = Builder.CreateIsNeg(A);
2333 // Copy the nuw/nsw flags from the sub to the negate.
2334 Value *NegA = Builder.CreateNeg(A, "", I.hasNoUnsignedWrap(),
2335 I.hasNoSignedWrap());
2336 return SelectInst::Create(IsNeg, NegA, A);
2337 }
2338
2339 // If we are subtracting a low-bit masked subset of some value from an add
2340 // of that same value with no low bits changed, that is clearing some low bits
2341 // of the sum:
2342 // sub (X + AddC), (X & AndC) --> and (X + AddC), ~AndC
2343 const APInt *AddC, *AndC;
2344 if (match(Op0, m_Add(m_Value(X), m_APInt(AddC))) &&
2345 match(Op1, m_And(m_Specific(X), m_APInt(AndC)))) {
2346 unsigned Cttz = AddC->countr_zero();
2347 APInt HighMask(APInt::getHighBitsSet(BitWidth, BitWidth - Cttz));
2348 if ((HighMask & *AndC).isZero())
2349 return BinaryOperator::CreateAnd(Op0, ConstantInt::get(Ty, ~(*AndC)));
2350 }
2351
2352 if (Instruction *V =
2354 return V;
2355
2356 // X - usub.sat(X, Y) => umin(X, Y)
2357 if (match(Op1, m_OneUse(m_Intrinsic<Intrinsic::usub_sat>(m_Specific(Op0),
2358 m_Value(Y)))))
2359 return replaceInstUsesWith(
2360 I, Builder.CreateIntrinsic(Intrinsic::umin, {I.getType()}, {Op0, Y}));
2361
2362 // umax(X, Op1) - Op1 --> usub.sat(X, Op1)
2363 // TODO: The one-use restriction is not strictly necessary, but it may
2364 // require improving other pattern matching and/or codegen.
2365 if (match(Op0, m_OneUse(m_c_UMax(m_Value(X), m_Specific(Op1)))))
2366 return replaceInstUsesWith(
2367 I, Builder.CreateIntrinsic(Intrinsic::usub_sat, {Ty}, {X, Op1}));
2368
2369 // Op0 - umin(X, Op0) --> usub.sat(Op0, X)
2370 if (match(Op1, m_OneUse(m_c_UMin(m_Value(X), m_Specific(Op0)))))
2371 return replaceInstUsesWith(
2372 I, Builder.CreateIntrinsic(Intrinsic::usub_sat, {Ty}, {Op0, X}));
2373
2374 // Op0 - umax(X, Op0) --> 0 - usub.sat(X, Op0)
2375 if (match(Op1, m_OneUse(m_c_UMax(m_Value(X), m_Specific(Op0))))) {
2376 Value *USub = Builder.CreateIntrinsic(Intrinsic::usub_sat, {Ty}, {X, Op0});
2377 return BinaryOperator::CreateNeg(USub);
2378 }
2379
2380 // umin(X, Op1) - Op1 --> 0 - usub.sat(Op1, X)
2381 if (match(Op0, m_OneUse(m_c_UMin(m_Value(X), m_Specific(Op1))))) {
2382 Value *USub = Builder.CreateIntrinsic(Intrinsic::usub_sat, {Ty}, {Op1, X});
2383 return BinaryOperator::CreateNeg(USub);
2384 }
2385
2386 // C - ctpop(X) => ctpop(~X) if C is bitwidth
2387 if (match(Op0, m_SpecificInt(BitWidth)) &&
2388 match(Op1, m_OneUse(m_Intrinsic<Intrinsic::ctpop>(m_Value(X)))))
2389 return replaceInstUsesWith(
2390 I, Builder.CreateIntrinsic(Intrinsic::ctpop, {I.getType()},
2391 {Builder.CreateNot(X)}));
2392
2393 // Reduce multiplies for difference-of-squares by factoring:
2394 // (X * X) - (Y * Y) --> (X + Y) * (X - Y)
2395 if (match(Op0, m_OneUse(m_Mul(m_Value(X), m_Deferred(X)))) &&
2396 match(Op1, m_OneUse(m_Mul(m_Value(Y), m_Deferred(Y))))) {
2397 auto *OBO0 = cast<OverflowingBinaryOperator>(Op0);
2398 auto *OBO1 = cast<OverflowingBinaryOperator>(Op1);
2399 bool PropagateNSW = I.hasNoSignedWrap() && OBO0->hasNoSignedWrap() &&
2400 OBO1->hasNoSignedWrap() && BitWidth > 2;
2401 bool PropagateNUW = I.hasNoUnsignedWrap() && OBO0->hasNoUnsignedWrap() &&
2402 OBO1->hasNoUnsignedWrap() && BitWidth > 1;
2403 Value *Add = Builder.CreateAdd(X, Y, "add", PropagateNUW, PropagateNSW);
2404 Value *Sub = Builder.CreateSub(X, Y, "sub", PropagateNUW, PropagateNSW);
2405 Value *Mul = Builder.CreateMul(Add, Sub, "", PropagateNUW, PropagateNSW);
2406 return replaceInstUsesWith(I, Mul);
2407 }
2408
2409 // max(X,Y) nsw/nuw - min(X,Y) --> abs(X nsw - Y)
2410 if (match(Op0, m_OneUse(m_c_SMax(m_Value(X), m_Value(Y)))) &&
2412 if (I.hasNoUnsignedWrap() || I.hasNoSignedWrap()) {
2413 Value *Sub =
2414 Builder.CreateSub(X, Y, "sub", /*HasNUW=*/false, /*HasNSW=*/true);
2415 Value *Call =
2416 Builder.CreateBinaryIntrinsic(Intrinsic::abs, Sub, Builder.getTrue());
2417 return replaceInstUsesWith(I, Call);
2418 }
2419 }
2420
2421 return TryToNarrowDeduceFlags();
2422}
2423
2424/// This eliminates floating-point negation in either 'fneg(X)' or
2425/// 'fsub(-0.0, X)' form by combining into a constant operand.
2427 // This is limited with one-use because fneg is assumed better for
2428 // reassociation and cheaper in codegen than fmul/fdiv.
2429 // TODO: Should the m_OneUse restriction be removed?
2430 Instruction *FNegOp;
2431 if (!match(&I, m_FNeg(m_OneUse(m_Instruction(FNegOp)))))
2432 return nullptr;
2433
2434 Value *X;
2435 Constant *C;
2436
2437 // Fold negation into constant operand.
2438 // -(X * C) --> X * (-C)
2439 if (match(FNegOp, m_FMul(m_Value(X), m_Constant(C))))
2440 if (Constant *NegC = ConstantFoldUnaryOpOperand(Instruction::FNeg, C, DL))
2441 return BinaryOperator::CreateFMulFMF(X, NegC, &I);
2442 // -(X / C) --> X / (-C)
2443 if (match(FNegOp, m_FDiv(m_Value(X), m_Constant(C))))
2444 if (Constant *NegC = ConstantFoldUnaryOpOperand(Instruction::FNeg, C, DL))
2445 return BinaryOperator::CreateFDivFMF(X, NegC, &I);
2446 // -(C / X) --> (-C) / X
2447 if (match(FNegOp, m_FDiv(m_Constant(C), m_Value(X))))
2448 if (Constant *NegC = ConstantFoldUnaryOpOperand(Instruction::FNeg, C, DL)) {
2450
2451 // Intersect 'nsz' and 'ninf' because those special value exceptions may
2452 // not apply to the fdiv. Everything else propagates from the fneg.
2453 // TODO: We could propagate nsz/ninf from fdiv alone?
2454 FastMathFlags FMF = I.getFastMathFlags();
2455 FastMathFlags OpFMF = FNegOp->getFastMathFlags();
2456 FDiv->setHasNoSignedZeros(FMF.noSignedZeros() && OpFMF.noSignedZeros());
2457 FDiv->setHasNoInfs(FMF.noInfs() && OpFMF.noInfs());
2458 return FDiv;
2459 }
2460 // With NSZ [ counter-example with -0.0: -(-0.0 + 0.0) != 0.0 + -0.0 ]:
2461 // -(X + C) --> -X + -C --> -C - X
2462 if (I.hasNoSignedZeros() && match(FNegOp, m_FAdd(m_Value(X), m_Constant(C))))
2463 if (Constant *NegC = ConstantFoldUnaryOpOperand(Instruction::FNeg, C, DL))
2464 return BinaryOperator::CreateFSubFMF(NegC, X, &I);
2465
2466 return nullptr;
2467}
2468
2470 InstCombiner::BuilderTy &Builder) {
2471 Value *FNeg;
2472 if (!match(&I, m_FNeg(m_Value(FNeg))))
2473 return nullptr;
2474
2475 Value *X, *Y;
2476 if (match(FNeg, m_OneUse(m_FMul(m_Value(X), m_Value(Y)))))
2477 return BinaryOperator::CreateFMulFMF(Builder.CreateFNegFMF(X, &I), Y, &I);
2478
2479 if (match(FNeg, m_OneUse(m_FDiv(m_Value(X), m_Value(Y)))))
2480 return BinaryOperator::CreateFDivFMF(Builder.CreateFNegFMF(X, &I), Y, &I);
2481
2482 return nullptr;
2483}
2484
2486 Value *Op = I.getOperand(0);
2487
2488 if (Value *V = simplifyFNegInst(Op, I.getFastMathFlags(),
2489 getSimplifyQuery().getWithInstruction(&I)))
2490 return replaceInstUsesWith(I, V);
2491
2493 return X;
2494
2495 Value *X, *Y;
2496
2497 // If we can ignore the sign of zeros: -(X - Y) --> (Y - X)
2498 if (I.hasNoSignedZeros() &&
2501
2503 return R;
2504
2505 Value *OneUse;
2506 if (!match(Op, m_OneUse(m_Value(OneUse))))
2507 return nullptr;
2508
2509 // Try to eliminate fneg if at least 1 arm of the select is negated.
2510 Value *Cond;
2511 if (match(OneUse, m_Select(m_Value(Cond), m_Value(X), m_Value(Y)))) {
2512 // Unlike most transforms, this one is not safe to propagate nsz unless
2513 // it is present on the original select. We union the flags from the select
2514 // and fneg and then remove nsz if needed.
2515 auto propagateSelectFMF = [&](SelectInst *S, bool CommonOperand) {
2516 S->copyFastMathFlags(&I);
2517 if (auto *OldSel = dyn_cast<SelectInst>(Op)) {
2518 FastMathFlags FMF = I.getFastMathFlags();
2519 FMF |= OldSel->getFastMathFlags();
2520 S->setFastMathFlags(FMF);
2521 if (!OldSel->hasNoSignedZeros() && !CommonOperand &&
2522 !isGuaranteedNotToBeUndefOrPoison(OldSel->getCondition()))
2523 S->setHasNoSignedZeros(false);
2524 }
2525 };
2526 // -(Cond ? -P : Y) --> Cond ? P : -Y
2527 Value *P;
2528 if (match(X, m_FNeg(m_Value(P)))) {
2529 Value *NegY = Builder.CreateFNegFMF(Y, &I, Y->getName() + ".neg");
2530 SelectInst *NewSel = SelectInst::Create(Cond, P, NegY);
2531 propagateSelectFMF(NewSel, P == Y);
2532 return NewSel;
2533 }
2534 // -(Cond ? X : -P) --> Cond ? -X : P
2535 if (match(Y, m_FNeg(m_Value(P)))) {
2536 Value *NegX = Builder.CreateFNegFMF(X, &I, X->getName() + ".neg");
2537 SelectInst *NewSel = SelectInst::Create(Cond, NegX, P);
2538 propagateSelectFMF(NewSel, P == X);
2539 return NewSel;
2540 }
2541 }
2542
2543 // fneg (copysign x, y) -> copysign x, (fneg y)
2544 if (match(OneUse, m_CopySign(m_Value(X), m_Value(Y)))) {
2545 // The source copysign has an additional value input, so we can't propagate
2546 // flags the copysign doesn't also have.
2547 FastMathFlags FMF = I.getFastMathFlags();
2548 FMF &= cast<FPMathOperator>(OneUse)->getFastMathFlags();
2549
2552
2553 Value *NegY = Builder.CreateFNeg(Y);
2554 Value *NewCopySign = Builder.CreateCopySign(X, NegY);
2555 return replaceInstUsesWith(I, NewCopySign);
2556 }
2557
2558 return nullptr;
2559}
2560
2562 if (Value *V = simplifyFSubInst(I.getOperand(0), I.getOperand(1),
2563 I.getFastMathFlags(),
2564 getSimplifyQuery().getWithInstruction(&I)))
2565 return replaceInstUsesWith(I, V);
2566
2568 return X;
2569
2571 return Phi;
2572
2573 // Subtraction from -0.0 is the canonical form of fneg.
2574 // fsub -0.0, X ==> fneg X
2575 // fsub nsz 0.0, X ==> fneg nsz X
2576 //
2577 // FIXME This matcher does not respect FTZ or DAZ yet:
2578 // fsub -0.0, Denorm ==> +-0
2579 // fneg Denorm ==> -Denorm
2580 Value *Op;
2581 if (match(&I, m_FNeg(m_Value(Op))))
2582 return UnaryOperator::CreateFNegFMF(Op, &I);
2583
2585 return X;
2586
2588 return R;
2589
2590 Value *X, *Y;
2591 Constant *C;
2592
2593 Value *Op0 = I.getOperand(0), *Op1 = I.getOperand(1);
2594 // If Op0 is not -0.0 or we can ignore -0.0: Z - (X - Y) --> Z + (Y - X)
2595 // Canonicalize to fadd to make analysis easier.
2596 // This can also help codegen because fadd is commutative.
2597 // Note that if this fsub was really an fneg, the fadd with -0.0 will get
2598 // killed later. We still limit that particular transform with 'hasOneUse'
2599 // because an fneg is assumed better/cheaper than a generic fsub.
2600 if (I.hasNoSignedZeros() || CannotBeNegativeZero(Op0, SQ.TLI)) {
2601 if (match(Op1, m_OneUse(m_FSub(m_Value(X), m_Value(Y))))) {
2602 Value *NewSub = Builder.CreateFSubFMF(Y, X, &I);
2603 return BinaryOperator::CreateFAddFMF(Op0, NewSub, &I);
2604 }
2605 }
2606
2607 // (-X) - Op1 --> -(X + Op1)
2608 if (I.hasNoSignedZeros() && !isa<ConstantExpr>(Op0) &&
2609 match(Op0, m_OneUse(m_FNeg(m_Value(X))))) {
2610 Value *FAdd = Builder.CreateFAddFMF(X, Op1, &I);
2612 }
2613
2614 if (isa<Constant>(Op0))
2615 if (SelectInst *SI = dyn_cast<SelectInst>(Op1))
2616 if (Instruction *NV = FoldOpIntoSelect(I, SI))
2617 return NV;
2618
2619 // X - C --> X + (-C)
2620 // But don't transform constant expressions because there's an inverse fold
2621 // for X + (-Y) --> X - Y.
2622 if (match(Op1, m_ImmConstant(C)))
2623 if (Constant *NegC = ConstantFoldUnaryOpOperand(Instruction::FNeg, C, DL))
2624 return BinaryOperator::CreateFAddFMF(Op0, NegC, &I);
2625
2626 // X - (-Y) --> X + Y
2627 if (match(Op1, m_FNeg(m_Value(Y))))
2628 return BinaryOperator::CreateFAddFMF(Op0, Y, &I);
2629
2630 // Similar to above, but look through a cast of the negated value:
2631 // X - (fptrunc(-Y)) --> X + fptrunc(Y)
2632 Type *Ty = I.getType();
2633 if (match(Op1, m_OneUse(m_FPTrunc(m_FNeg(m_Value(Y))))))
2635
2636 // X - (fpext(-Y)) --> X + fpext(Y)
2637 if (match(Op1, m_OneUse(m_FPExt(m_FNeg(m_Value(Y))))))
2639
2640 // Similar to above, but look through fmul/fdiv of the negated value:
2641 // Op0 - (-X * Y) --> Op0 + (X * Y)
2642 // Op0 - (Y * -X) --> Op0 + (X * Y)
2643 if (match(Op1, m_OneUse(m_c_FMul(m_FNeg(m_Value(X)), m_Value(Y))))) {
2645 return BinaryOperator::CreateFAddFMF(Op0, FMul, &I);
2646 }
2647 // Op0 - (-X / Y) --> Op0 + (X / Y)
2648 // Op0 - (X / -Y) --> Op0 + (X / Y)
2649 if (match(Op1, m_OneUse(m_FDiv(m_FNeg(m_Value(X)), m_Value(Y)))) ||
2650 match(Op1, m_OneUse(m_FDiv(m_Value(X), m_FNeg(m_Value(Y)))))) {
2651 Value *FDiv = Builder.CreateFDivFMF(X, Y, &I);
2652 return BinaryOperator::CreateFAddFMF(Op0, FDiv, &I);
2653 }
2654
2655 // Handle special cases for FSub with selects feeding the operation
2656 if (Value *V = SimplifySelectsFeedingBinaryOp(I, Op0, Op1))
2657 return replaceInstUsesWith(I, V);
2658
2659 if (I.hasAllowReassoc() && I.hasNoSignedZeros()) {
2660 // (Y - X) - Y --> -X
2661 if (match(Op0, m_FSub(m_Specific(Op1), m_Value(X))))
2663
2664 // Y - (X + Y) --> -X
2665 // Y - (Y + X) --> -X
2666 if (match(Op1, m_c_FAdd(m_Specific(Op0), m_Value(X))))
2668
2669 // (X * C) - X --> X * (C - 1.0)
2670 if (match(Op0, m_FMul(m_Specific(Op1), m_Constant(C)))) {
2672 Instruction::FSub, C, ConstantFP::get(Ty, 1.0), DL))
2673 return BinaryOperator::CreateFMulFMF(Op1, CSubOne, &I);
2674 }
2675 // X - (X * C) --> X * (1.0 - C)
2676 if (match(Op1, m_FMul(m_Specific(Op0), m_Constant(C)))) {
2678 Instruction::FSub, ConstantFP::get(Ty, 1.0), C, DL))
2679 return BinaryOperator::CreateFMulFMF(Op0, OneSubC, &I);
2680 }
2681
2682 // Reassociate fsub/fadd sequences to create more fadd instructions and
2683 // reduce dependency chains:
2684 // ((X - Y) + Z) - Op1 --> (X + Z) - (Y + Op1)
2685 Value *Z;
2687 m_Value(Z))))) {
2688 Value *XZ = Builder.CreateFAddFMF(X, Z, &I);
2689 Value *YW = Builder.CreateFAddFMF(Y, Op1, &I);
2690 return BinaryOperator::CreateFSubFMF(XZ, YW, &I);
2691 }
2692
2693 auto m_FaddRdx = [](Value *&Sum, Value *&Vec) {
2694 return m_OneUse(m_Intrinsic<Intrinsic::vector_reduce_fadd>(m_Value(Sum),
2695 m_Value(Vec)));
2696 };
2697 Value *A0, *A1, *V0, *V1;
2698 if (match(Op0, m_FaddRdx(A0, V0)) && match(Op1, m_FaddRdx(A1, V1)) &&
2699 V0->getType() == V1->getType()) {
2700 // Difference of sums is sum of differences:
2701 // add_rdx(A0, V0) - add_rdx(A1, V1) --> add_rdx(A0, V0 - V1) - A1
2702 Value *Sub = Builder.CreateFSubFMF(V0, V1, &I);
2703 Value *Rdx = Builder.CreateIntrinsic(Intrinsic::vector_reduce_fadd,
2704 {Sub->getType()}, {A0, Sub}, &I);
2705 return BinaryOperator::CreateFSubFMF(Rdx, A1, &I);
2706 }
2707
2709 return F;
2710
2711 // TODO: This performs reassociative folds for FP ops. Some fraction of the
2712 // functionality has been subsumed by simple pattern matching here and in
2713 // InstSimplify. We should let a dedicated reassociation pass handle more
2714 // complex pattern matching and remove this from InstCombine.
2715 if (Value *V = FAddCombine(Builder).simplify(&I))
2716 return replaceInstUsesWith(I, V);
2717
2718 // (X - Y) - Op1 --> X - (Y + Op1)
2719 if (match(Op0, m_OneUse(m_FSub(m_Value(X), m_Value(Y))))) {
2720 Value *FAdd = Builder.CreateFAddFMF(Y, Op1, &I);
2722 }
2723 }
2724
2725 return nullptr;
2726}
MachineBasicBlock MachineBasicBlock::iterator DebugLoc DL
static bool isConstant(const MachineInstr &MI)
amdgpu AMDGPU Register Bank Select
This file declares a class to represent arbitrary precision floating point values and provide a varie...
This file implements a class to represent arbitrary precision integral constant values and operations...
assume Assume Builder
SmallVector< MachineOperand, 4 > Cond
static GCRegistry::Add< OcamlGC > B("ocaml", "ocaml 3.10-compatible GC")
static GCRegistry::Add< ErlangGC > A("erlang", "erlang-compatible garbage collector")
static GCRegistry::Add< CoreCLRGC > E("coreclr", "CoreCLR-compatible GC")
This file contains the declarations for the subclasses of Constant, which represent the different fla...
Returns the sub type a function will return at a given Idx Should correspond to the result type of an ExtractValue instruction executed with just that one unsigned Idx
static GCMetadataPrinterRegistry::Add< ErlangGCPrinter > X("erlang", "erlang-compatible garbage collector")
hexagon bit simplify
static Instruction * factorizeFAddFSub(BinaryOperator &I, InstCombiner::BuilderTy &Builder)
Factor a common operand out of fadd/fsub of fmul/fdiv.
static Instruction * foldAddToAshr(BinaryOperator &Add)
Try to reduce signed division by power-of-2 to an arithmetic shift right.
static bool MatchMul(Value *E, Value *&Op, APInt &C)
static bool MatchDiv(Value *E, Value *&Op, APInt &C, bool IsSigned)
static Instruction * foldFNegIntoConstant(Instruction &I, const DataLayout &DL)
This eliminates floating-point negation in either 'fneg(X)' or 'fsub(-0.0, X)' form by combining into...
static Instruction * factorizeLerp(BinaryOperator &I, InstCombiner::BuilderTy &Builder)
Eliminate an op from a linear interpolation (lerp) pattern.
static Instruction * foldSubOfMinMax(BinaryOperator &I, InstCombiner::BuilderTy &Builder)
static Instruction * foldBoxMultiply(BinaryOperator &I)
Reduce a sequence of masked half-width multiplies to a single multiply.
static Value * checkForNegativeOperand(BinaryOperator &I, InstCombiner::BuilderTy &Builder)
static Instruction * hoistFNegAboveFMulFDiv(Instruction &I, InstCombiner::BuilderTy &Builder)
static bool MulWillOverflow(APInt &C0, APInt &C1, bool IsSigned)
static Instruction * foldNoWrapAdd(BinaryOperator &Add, InstCombiner::BuilderTy &Builder)
Wrapping flags may allow combining constants separated by an extend.
static Instruction * factorizeMathWithShlOps(BinaryOperator &I, InstCombiner::BuilderTy &Builder)
This is a specialization of a more general transform from foldUsingDistributiveLaws.
static Instruction * canonicalizeLowbitMask(BinaryOperator &I, InstCombiner::BuilderTy &Builder)
Fold (1 << NBits) - 1 Into: ~(-(1 << NBits)) Because a 'not' is better for bit-tracking analysis and ...
static Instruction * foldToUnsignedSaturatedAdd(BinaryOperator &I)
static bool MatchRem(Value *E, Value *&Op, APInt &C, bool &IsSigned)
This file provides internal interfaces used to implement the InstCombine.
This file provides the interface for the instcombine pass implementation.
static bool isZero(Value *V, const DataLayout &DL, DominatorTree *DT, AssumptionCache *AC)
Definition: Lint.cpp:524
#define F(x, y, z)
Definition: MD5.cpp:55
#define I(x, y, z)
Definition: MD5.cpp:58
static GCMetadataPrinterRegistry::Add< OcamlGCMetadataPrinter > Y("ocaml", "ocaml 3.10-compatible collector")
#define P(N)
@ SI
assert(ImpDefSCC.getReg()==AMDGPU::SCC &&ImpDefSCC.isDef())
This file contains some templates that are useful if you are working with the STL at all.
This file defines the SmallVector class.
Value * RHS
Value * LHS
const fltSemantics & getSemantics() const
Definition: APFloat.h:1277
opStatus multiply(const APFloat &RHS, roundingMode RM)
Definition: APFloat.h:1034
Class for arbitrary precision integers.
Definition: APInt.h:75
APInt umul_ov(const APInt &RHS, bool &Overflow) const
Definition: APInt.cpp:1969
bool isNegatedPowerOf2() const
Check if this APInt's negated value is a power of two greater than zero.
Definition: APInt.h:441
bool isMinSignedValue() const
Determine if this is the smallest signed value.
Definition: APInt.h:415
APInt trunc(unsigned width) const
Truncate to new width.
Definition: APInt.cpp:898
static APInt getMaxValue(unsigned numBits)
Gets maximum unsigned value of APInt for specific bit width.
Definition: APInt.h:186
bool isSignMask() const
Check if the APInt's value is returned by getSignMask.
Definition: APInt.h:454
unsigned getBitWidth() const
Return the number of bits in the APInt.
Definition: APInt.h:1439
bool isNegative() const
Determine sign of this APInt.
Definition: APInt.h:312
int32_t exactLogBase2() const
Definition: APInt.h:1729
unsigned countr_zero() const
Count the number of trailing zero bits.
Definition: APInt.h:1592
unsigned countl_zero() const
The APInt version of std::countl_zero.
Definition: APInt.h:1551
static APInt getSignedMinValue(unsigned numBits)
Gets minimum signed value of APInt for a specific bit width.
Definition: APInt.h:199
unsigned logBase2() const
Definition: APInt.h:1707
APInt smul_ov(const APInt &RHS, bool &Overflow) const
Definition: APInt.cpp:1958
bool isMask(unsigned numBits) const
Definition: APInt.h:476
APInt sext(unsigned width) const
Sign extend to a new width.
Definition: APInt.cpp:946
bool isSubsetOf(const APInt &RHS) const
This operation checks that all bits set in this APInt are also set in RHS.
Definition: APInt.h:1235
bool isPowerOf2() const
Check if this APInt's value is a power of two greater than zero.
Definition: APInt.h:432
static APInt getHighBitsSet(unsigned numBits, unsigned hiBitsSet)
Constructs an APInt value that has the top hiBitsSet bits set.
Definition: APInt.h:279
bool sge(const APInt &RHS) const
Signed greater or equal comparison.
Definition: APInt.h:1215
static BinaryOperator * CreateFDivFMF(Value *V1, Value *V2, Instruction *FMFSource, const Twine &Name="")
Definition: InstrTypes.h:271
static BinaryOperator * CreateNeg(Value *Op, const Twine &Name="", Instruction *InsertBefore=nullptr)
Helper functions to construct and inspect unary operations (NEG and NOT) via binary operators SUB and...
static BinaryOperator * CreateNot(Value *Op, const Twine &Name="", Instruction *InsertBefore=nullptr)
static BinaryOperator * CreateFMulFMF(Value *V1, Value *V2, Instruction *FMFSource, const Twine &Name="")
Definition: InstrTypes.h:266
static BinaryOperator * CreateFSubFMF(Value *V1, Value *V2, Instruction *FMFSource, const Twine &Name="")
Definition: InstrTypes.h:261
static BinaryOperator * CreateFAddFMF(Value *V1, Value *V2, Instruction *FMFSource, const Twine &Name="")
Definition: InstrTypes.h:256
static CallInst * Create(FunctionType *Ty, Value *F, const Twine &NameStr="", Instruction *InsertBefore=nullptr)
static CastInst * Create(Instruction::CastOps, Value *S, Type *Ty, const Twine &Name="", Instruction *InsertBefore=nullptr)
Provides a way to construct any of the CastInst subclasses using an opcode instead of the subclass's ...
static CastInst * CreateTruncOrBitCast(Value *S, Type *Ty, const Twine &Name="", Instruction *InsertBefore=nullptr)
Create a Trunc or BitCast cast instruction.
Predicate
This enumeration lists the possible predicates for CmpInst subclasses.
Definition: InstrTypes.h:718
@ ICMP_UGT
unsigned greater than
Definition: InstrTypes.h:741
@ ICMP_SGT
signed greater than
Definition: InstrTypes.h:745
@ ICMP_EQ
equal
Definition: InstrTypes.h:739
static Constant * getSub(Constant *C1, Constant *C2, bool HasNUW=false, bool HasNSW=false)
Definition: Constants.cpp:2621
static Constant * getZExt(Constant *C, Type *Ty, bool OnlyIfReduced=false)
Definition: Constants.cpp:2110
static Constant * getSIToFP(Constant *C, Type *Ty, bool OnlyIfReduced=false)
Definition: Constants.cpp:2159
static Constant * getSExt(Constant *C, Type *Ty, bool OnlyIfReduced=false)
Definition: Constants.cpp:2096
static Constant * getFPToSI(Constant *C, Type *Ty, bool OnlyIfReduced=false)
Definition: Constants.cpp:2181
static Constant * getAdd(Constant *C1, Constant *C2, bool HasNUW=false, bool HasNSW=false)
Definition: Constants.cpp:2614
ConstantFP - Floating Point Values [float, double].
Definition: Constants.h:260
const APFloat & getValueAPF() const
Definition: Constants.h:301
static Constant * get(Type *Ty, double V)
This returns a ConstantFP, or a vector containing a splat of a ConstantFP, for the specified value in...
Definition: Constants.cpp:927
bool isZero() const
Return true if the value is positive or negative zero.
Definition: Constants.h:305
static Constant * get(Type *Ty, uint64_t V, bool IsSigned=false)
If Ty is a vector type, return a Constant with a splat of the given value.
Definition: Constants.cpp:888
This is an important base class in LLVM.
Definition: Constant.h:41
static Constant * getAllOnesValue(Type *Ty)
Definition: Constants.cpp:403
static Constant * getNullValue(Type *Ty)
Constructor to create a '0' constant of arbitrary type.
Definition: Constants.cpp:356
A parsed version of the target data layout string in and methods for querying it.
Definition: DataLayout.h:110
Convenience struct for specifying and reasoning about fast-math flags.
Definition: FMF.h:21
bool noSignedZeros() const
Definition: FMF.h:69
bool noInfs() const
Definition: FMF.h:68
bool isInBounds() const
Test whether this is an inbounds GEP, as defined by LangRef.html.
Definition: Operator.h:395
unsigned countNonConstantIndices() const
Definition: Operator.h:475
Value * CreateFAddFMF(Value *L, Value *R, Instruction *FMFSource, const Twine &Name="")
Copy fast-math-flags from an instruction rather than using the builder's default FMF.
Definition: IRBuilder.h:1470
Value * CreateNeg(Value *V, const Twine &Name="", bool HasNUW=false, bool HasNSW=false)
Definition: IRBuilder.h:1639
Value * CreateSRem(Value *LHS, Value *RHS, const Twine &Name="")
Definition: IRBuilder.h:1333
Value * CreateFMulFMF(Value *L, Value *R, Instruction *FMFSource, const Twine &Name="")
Copy fast-math-flags from an instruction rather than using the builder's default FMF.
Definition: IRBuilder.h:1524
Value * CreateFSubFMF(Value *L, Value *R, Instruction *FMFSource, const Twine &Name="")
Copy fast-math-flags from an instruction rather than using the builder's default FMF.
Definition: IRBuilder.h:1497
Value * CreateFDivFMF(Value *L, Value *R, Instruction *FMFSource, const Twine &Name="")
Copy fast-math-flags from an instruction rather than using the builder's default FMF.
Definition: IRBuilder.h:1551
Value * CreateFPTrunc(Value *V, Type *DestTy, const Twine &Name="")
Definition: IRBuilder.h:1990
ConstantInt * getTrue()
Get the constant value for i1 true.
Definition: IRBuilder.h:452
CallInst * CreateIntrinsic(Intrinsic::ID ID, ArrayRef< Type * > Types, ArrayRef< Value * > Args, Instruction *FMFSource=nullptr, const Twine &Name="")
Create a call to intrinsic ID with Args, mangled using Types.
Definition: IRBuilder.cpp:973
Value * CreateFNegFMF(Value *V, Instruction *FMFSource, const Twine &Name="")
Copy fast-math-flags from an instruction rather than using the builder's default FMF.
Definition: IRBuilder.h:1663
Value * CreateIsNotNeg(Value *Arg, const Twine &Name="")
Return a boolean value testing if Arg > -1.
Definition: IRBuilder.h:2448
Value * CreateNSWAdd(Value *LHS, Value *RHS, const Twine &Name="")
Definition: IRBuilder.h:1259
void setFastMathFlags(FastMathFlags NewFMF)
Set the fast-math flags to be used with generated fp-math operators.
Definition: IRBuilder.h:297
CallInst * CreateCopySign(Value *LHS, Value *RHS, Instruction *FMFSource=nullptr, const Twine &Name="")
Create call to the copysign intrinsic.
Definition: IRBuilder.h:956
Value * CreateZExt(Value *V, Type *DestTy, const Twine &Name="")
Definition: IRBuilder.h:1924
Value * CreateNot(Value *V, const Twine &Name="")
Definition: IRBuilder.h:1672
InstTy * Insert(InstTy *I, const Twine &Name="") const
Insert and return the specified instruction.
Definition: IRBuilder.h:145
Value * CreateIsNeg(Value *Arg, const Twine &Name="")
Return a boolean value testing if Arg < 0.
Definition: IRBuilder.h:2443
Value * CreateSub(Value *LHS, Value *RHS, const Twine &Name="", bool HasNUW=false, bool HasNSW=false)
Definition: IRBuilder.h:1267
Value * CreateShl(Value *LHS, Value *RHS, const Twine &Name="", bool HasNUW=false, bool HasNSW=false)
Definition: IRBuilder.h:1339
CallInst * CreateBinaryIntrinsic(Intrinsic::ID ID, Value *LHS, Value *RHS, Instruction *FMFSource=nullptr, const Twine &Name="")
Create a call to intrinsic ID with 2 operands which is mangled on the first type.
Definition: IRBuilder.cpp:964
Value * CreateAnd(Value *LHS, Value *RHS, const Twine &Name="")
Definition: IRBuilder.h:1398
Value * CreateAdd(Value *LHS, Value *RHS, const Twine &Name="", bool HasNUW=false, bool HasNSW=false)
Definition: IRBuilder.h:1250
Value * CreateIsNotNull(Value *Arg, const Twine &Name="")
Return a boolean value testing if Arg != 0.
Definition: IRBuilder.h:2438
Value * CreateIntCast(Value *V, Type *DestTy, bool isSigned, const Twine &Name="")
Definition: IRBuilder.h:2085
Value * CreateFPExt(Value *V, Type *DestTy, const Twine &Name="")
Definition: IRBuilder.h:1999
Value * CreateXor(Value *LHS, Value *RHS, const Twine &Name="")
Definition: IRBuilder.h:1442
Value * CreateFNeg(Value *V, const Twine &Name="", MDNode *FPMathTag=nullptr)
Definition: IRBuilder.h:1653
Value * CreateURem(Value *LHS, Value *RHS, const Twine &Name="")
Definition: IRBuilder.h:1327
Value * CreateMul(Value *LHS, Value *RHS, const Twine &Name="", bool HasNUW=false, bool HasNSW=false)
Definition: IRBuilder.h:1284
Instruction * FoldOpIntoSelect(Instruction &Op, SelectInst *SI, bool FoldWithMultiUse=false)
Given an instruction with a select as one operand and a constant as the other operand,...
Instruction * visitAdd(BinaryOperator &I)
Instruction * canonicalizeCondSignextOfHighBitExtractToSignextHighBitExtract(BinaryOperator &I)
Instruction * foldBinOpIntoSelectOrPhi(BinaryOperator &I)
This is a convenience wrapper function for the above two functions.
bool SimplifyAssociativeOrCommutative(BinaryOperator &I)
Performs a few simplifications for operators which are associative or commutative.
Value * foldUsingDistributiveLaws(BinaryOperator &I)
Tries to simplify binary operations which some other binary operation distributes over.
Instruction * foldOpIntoPhi(Instruction &I, PHINode *PN)
Given a binary operator, cast instruction, or select which has a PHI node as operand #0,...
Instruction * visitSub(BinaryOperator &I)
Value * OptimizePointerDifference(Value *LHS, Value *RHS, Type *Ty, bool isNUW)
Optimize pointer differences into the same array into a size.
Instruction * visitFAdd(BinaryOperator &I)
Instruction * foldBinopWithPhiOperands(BinaryOperator &BO)
For a binary operator with 2 phi operands, try to hoist the binary operation before the phi.
Value * SimplifyAddWithRemainder(BinaryOperator &I)
Tries to simplify add operations using the definition of remainder.
Instruction * foldAddWithConstant(BinaryOperator &Add)
Instruction * foldVectorBinop(BinaryOperator &Inst)
Canonicalize the position of binops relative to shufflevector.
Value * SimplifySelectsFeedingBinaryOp(BinaryOperator &I, Value *LHS, Value *RHS)
Instruction * visitFNeg(UnaryOperator &I)
Instruction * visitFSub(BinaryOperator &I)
Instruction * replaceInstUsesWith(Instruction &I, Value *V)
A combiner-aware RAUW-like routine.
Definition: InstCombiner.h:418
static bool isFreeToInvert(Value *V, bool WillInvertAllUses)
Return true if the specified value is free to invert (apply ~ to).
Definition: InstCombiner.h:235
static Constant * SubOne(Constant *C)
Subtract one from a Constant.
Definition: InstCombiner.h:207
const SimplifyQuery SQ
Definition: InstCombiner.h:74
const DataLayout & DL
Definition: InstCombiner.h:73
unsigned ComputeNumSignBits(const Value *Op, unsigned Depth=0, const Instruction *CxtI=nullptr) const
Definition: InstCombiner.h:482
AssumptionCache & AC
Definition: InstCombiner.h:70
Instruction * replaceOperand(Instruction &I, unsigned OpNum, Value *V)
Replace operand of instruction and add old operand to the worklist.
Definition: InstCombiner.h:442
DominatorTree & DT
Definition: InstCombiner.h:72
static bool isSignBitCheck(ICmpInst::Predicate Pred, const APInt &RHS, bool &TrueIfSigned)
Given an exploded icmp instruction, return true if the comparison only checks the sign bit.
Definition: InstCombiner.h:165
void computeKnownBits(const Value *V, KnownBits &Known, unsigned Depth, const Instruction *CxtI) const
Definition: InstCombiner.h:461
BuilderTy & Builder
Definition: InstCombiner.h:58
bool MaskedValueIsZero(const Value *V, const APInt &Mask, unsigned Depth=0, const Instruction *CxtI=nullptr) const
Definition: InstCombiner.h:477
const SimplifyQuery & getSimplifyQuery() const
Definition: InstCombiner.h:373
static Constant * AddOne(Constant *C)
Add one to a Constant.
Definition: InstCombiner.h:202
bool hasNoUnsignedWrap() const LLVM_READONLY
Determine whether the no unsigned wrap flag is set.
void copyFastMathFlags(FastMathFlags FMF)
Convenience function for transferring all fast-math flag values to this instruction,...
void setHasNoSignedZeros(bool B)
Set or clear the no-signed-zeros flag on this instruction, which must be an operator which supports t...
void setHasNoSignedWrap(bool b=true)
Set or clear the nsw flag on this instruction, which must be an operator which supports this flag.
void setFastMathFlags(FastMathFlags FMF)
Convenience function for setting multiple fast-math flags on this instruction, which must be an opera...
void setHasNoInfs(bool B)
Set or clear the no-infs flag on this instruction, which must be an operator which supports this flag...
FastMathFlags getFastMathFlags() const LLVM_READONLY
Convenience function for getting all the fast-math flags, which must be an operator which supports th...
void setDebugLoc(DebugLoc Loc)
Set the debug location information for this instruction.
Definition: Instruction.h:355
void copyMetadata(const Instruction &SrcInst, ArrayRef< unsigned > WL=ArrayRef< unsigned >())
Copy metadata from SrcInst to this instruction.
static Value * Negate(bool LHSIsZero, Value *Root, InstCombinerImpl &IC)
Attempt to negate Root.
This class represents a cast from signed integer to floating point.
This class represents the LLVM 'select' instruction.
static SelectInst * Create(Value *C, Value *S1, Value *S2, const Twine &NameStr="", Instruction *InsertBefore=nullptr, Instruction *MDFrom=nullptr)
This is a 'vector' (really, a variable-sized array), optimized for the case when the array is small.
Definition: SmallVector.h:1200
The instances of the Type class are immutable: once they are created, they are never changed.
Definition: Type.h:45
unsigned getIntegerBitWidth() const
const fltSemantics & getFltSemantics() const
bool isIntOrIntVectorTy() const
Return true if this is an integer type or a vector of integer types.
Definition: Type.h:237
unsigned getScalarSizeInBits() const LLVM_READONLY
If this is a vector type, return the getPrimitiveSizeInBits value for the element type.
Type * getScalarType() const
If this is a vector type, return the element type, otherwise return 'this'.
Definition: Type.h:350
static UnaryOperator * CreateFNegFMF(Value *Op, Instruction *FMFSource, const Twine &Name="", Instruction *InsertBefore=nullptr)
Definition: InstrTypes.h:163
LLVM Value Representation.
Definition: Value.h:74
Type * getType() const
All values are typed, get the type of this value.
Definition: Value.h:255
bool hasOneUse() const
Return true if there is exactly one use of this value.
Definition: Value.h:434
bool hasNUsesOrMore(unsigned N) const
Return true if this value has N uses or more.
Definition: Value.cpp:152
const Value * stripPointerCasts() const
Strip off pointer casts, all-zero GEPs and address space casts.
Definition: Value.cpp:685
StringRef getName() const
Return a constant reference to the value's name.
Definition: Value.cpp:308
This class represents zero extension of integer types.
@ C
The default llvm calling convention, compatible with C.
Definition: CallingConv.h:34
Function * getDeclaration(Module *M, ID id, ArrayRef< Type * > Tys=std::nullopt)
Create or insert an LLVM Function declaration for an intrinsic, and return it.
Definition: Function.cpp:1506
cst_pred_ty< is_all_ones > m_AllOnes()
Match an integer or vector with all bits set.
Definition: PatternMatch.h:453
BinaryOp_match< LHS, RHS, Instruction::And > m_And(const LHS &L, const RHS &R)
specific_intval< false > m_SpecificInt(APInt V)
Match a specific integer value or vector with all elements equal to the value.
Definition: PatternMatch.h:854
match_combine_or< CastClass_match< OpTy, Instruction::ZExt >, OpTy > m_ZExtOrSelf(const OpTy &Op)
BinaryOp_match< LHS, RHS, Instruction::Add > m_Add(const LHS &L, const RHS &R)
Definition: PatternMatch.h:979
class_match< BinaryOperator > m_BinOp()
Match an arbitrary binary operation and ignore it.
Definition: PatternMatch.h:84
BinaryOp_match< LHS, RHS, Instruction::FMul, true > m_c_FMul(const LHS &L, const RHS &R)
Matches FMul with LHS and RHS in either order.
cst_pred_ty< is_sign_mask > m_SignMask()
Match an integer or vector with only the sign bit(s) set.
Definition: PatternMatch.h:576
OverflowingBinaryOp_match< LHS, RHS, Instruction::Add, OverflowingBinaryOperator::NoUnsignedWrap > m_NUWAdd(const LHS &L, const RHS &R)
BinaryOp_match< LHS, RHS, Instruction::AShr > m_AShr(const LHS &L, const RHS &R)
BinaryOp_match< LHS, RHS, Instruction::FSub > m_FSub(const LHS &L, const RHS &R)
Definition: PatternMatch.h:997
cst_pred_ty< is_power2 > m_Power2()
Match an integer or vector power-of-2.
Definition: PatternMatch.h:544
BinaryOp_match< LHS, RHS, Instruction::URem > m_URem(const LHS &L, const RHS &R)
CastClass_match< OpTy, Instruction::SExt > m_SExt(const OpTy &Op)
Matches SExt.
class_match< Constant > m_Constant()
Match an arbitrary Constant and ignore it.
Definition: PatternMatch.h:144
BinaryOp_match< LHS, RHS, Instruction::And, true > m_c_And(const LHS &L, const RHS &R)
Matches an And with LHS and RHS in either order.
BinaryOp_match< LHS, RHS, Instruction::Xor > m_Xor(const LHS &L, const RHS &R)
CastClass_match< OpTy, Instruction::ZExt > m_ZExt(const OpTy &Op)
Matches ZExt.
OverflowingBinaryOp_match< LHS, RHS, Instruction::Sub, OverflowingBinaryOperator::NoSignedWrap > m_NSWSub(const LHS &L, const RHS &R)
BinaryOp_match< LHS, RHS, Instruction::FMul > m_FMul(const LHS &L, const RHS &R)
bool match(Val *V, const Pattern &P)
Definition: PatternMatch.h:49
bind_ty< Instruction > m_Instruction(Instruction *&I)
Match an instruction, capturing it if we match.
Definition: PatternMatch.h:716
cstfp_pred_ty< is_any_zero_fp > m_AnyZeroFP()
Match a floating-point negative zero or positive zero.
Definition: PatternMatch.h:664
specificval_ty m_Specific(const Value *V)
Match if we have a specific specified value.
Definition: PatternMatch.h:772
cst_pred_ty< is_one > m_One()
Match an integer 1 or a vector with all elements equal to 1.
Definition: PatternMatch.h:517
ThreeOps_match< Cond, LHS, RHS, Instruction::Select > m_Select(const Cond &C, const LHS &L, const RHS &R)
Matches SelectInst.
match_combine_and< LTy, RTy > m_CombineAnd(const LTy &L, const RTy &R)
Combine two pattern matchers matching L && R.
Definition: PatternMatch.h:224
BinaryOp_match< LHS, RHS, Instruction::Xor, true > m_c_Xor(const LHS &L, const RHS &R)
Matches an Xor with LHS and RHS in either order.
BinaryOp_match< LHS, RHS, Instruction::FAdd > m_FAdd(const LHS &L, const RHS &R)
Definition: PatternMatch.h:985
BinaryOp_match< LHS, RHS, Instruction::Mul > m_Mul(const LHS &L, const RHS &R)
deferredval_ty< Value > m_Deferred(Value *const &V)
Like m_Specific(), but works if the specific value to match is determined as part of the same match()...
Definition: PatternMatch.h:790
cst_pred_ty< is_zero_int > m_ZeroInt()
Match an integer 0 or a vector with all elements equal to 0.
Definition: PatternMatch.h:524
CastClass_match< OpTy, Instruction::FPTrunc > m_FPTrunc(const OpTy &Op)
CmpClass_match< LHS, RHS, ICmpInst, ICmpInst::Predicate > m_ICmp(ICmpInst::Predicate &Pred, const LHS &L, const RHS &R)
OneUse_match< T > m_OneUse(const T &SubPattern)
Definition: PatternMatch.h:67
MaxMin_match< ICmpInst, LHS, RHS, smin_pred_ty, true > m_c_SMin(const LHS &L, const RHS &R)
Matches an SMin with LHS and RHS in either order.
BinaryOp_match< cst_pred_ty< is_zero_int >, ValTy, Instruction::Sub > m_Neg(const ValTy &V)
Matches a 'Neg' as 'sub 0, V'.
CastClass_match< OpTy, Instruction::PtrToInt > m_PtrToInt(const OpTy &Op)
Matches PtrToInt.
match_combine_and< class_match< Constant >, match_unless< constantexpr_match > > m_ImmConstant()
Match an arbitrary immediate Constant and ignore it.
Definition: PatternMatch.h:751
MaxMin_match< ICmpInst, LHS, RHS, umax_pred_ty, true > m_c_UMax(const LHS &L, const RHS &R)
Matches a UMax with LHS and RHS in either order.
CastClass_match< OpTy, Instruction::Trunc > m_Trunc(const OpTy &Op)
Matches Trunc.
BinaryOp_match< LHS, RHS, Instruction::UDiv > m_UDiv(const LHS &L, const RHS &R)
match_combine_or< CastClass_match< OpTy, Instruction::Trunc >, OpTy > m_TruncOrSelf(const OpTy &Op)
cst_pred_ty< is_negated_power2 > m_NegatedPower2()
Match a integer or vector negated power-of-2.
Definition: PatternMatch.h:552
specific_fpval m_FPOne()
Match a float 1.0 or vector with all elements equal to 1.0.
Definition: PatternMatch.h:818
MaxMin_match< ICmpInst, LHS, RHS, umin_pred_ty, true > m_c_UMin(const LHS &L, const RHS &R)
Matches a UMin with LHS and RHS in either order.
BinaryOp_match< LHS, RHS, Instruction::Add, true > m_c_Add(const LHS &L, const RHS &R)
Matches a Add with LHS and RHS in either order.
CastClass_match< OpTy, Instruction::FPExt > m_FPExt(const OpTy &Op)
MaxMin_match< ICmpInst, LHS, RHS, smax_pred_ty, true > m_c_SMax(const LHS &L, const RHS &R)
Matches an SMax with LHS and RHS in either order.
match_combine_or< match_combine_or< MaxMin_match< ICmpInst, LHS, RHS, smax_pred_ty, true >, MaxMin_match< ICmpInst, LHS, RHS, smin_pred_ty, true > >, match_combine_or< MaxMin_match< ICmpInst, LHS, RHS, umax_pred_ty, true >, MaxMin_match< ICmpInst, LHS, RHS, umin_pred_ty, true > > > m_c_MaxOrMin(const LHS &L, const RHS &R)
BinaryOp_match< LHS, RHS, Instruction::SDiv > m_SDiv(const LHS &L, const RHS &R)
specific_intval< true > m_SpecificIntAllowUndef(APInt V)
Definition: PatternMatch.h:862
OverflowingBinaryOp_match< LHS, RHS, Instruction::Sub, OverflowingBinaryOperator::NoUnsignedWrap > m_NUWSub(const LHS &L, const RHS &R)
apint_match m_APInt(const APInt *&Res)
Match a ConstantInt or splatted ConstantVector, binding the specified pointer to the contained APInt.
Definition: PatternMatch.h:278
class_match< Value > m_Value()
Match an arbitrary value and ignore it.
Definition: PatternMatch.h:76
AnyBinaryOp_match< LHS, RHS, true > m_c_BinOp(const LHS &L, const RHS &R)
Matches a BinaryOperator with LHS and RHS in either order.
OverflowingBinaryOp_match< LHS, RHS, Instruction::Add, OverflowingBinaryOperator::NoSignedWrap > m_NSWAdd(const LHS &L, const RHS &R)
BinaryOp_match< LHS, RHS, Instruction::LShr > m_LShr(const LHS &L, const RHS &R)
FNeg_match< OpTy > m_FNeg(const OpTy &X)
Match 'fneg X' as 'fsub -0.0, X'.
BinaryOp_match< LHS, RHS, Instruction::FAdd, true > m_c_FAdd(const LHS &L, const RHS &R)
Matches FAdd with LHS and RHS in either order.
BinaryOp_match< LHS, RHS, Instruction::Shl > m_Shl(const LHS &L, const RHS &R)
BinaryOp_match< LHS, RHS, Instruction::FDiv > m_FDiv(const LHS &L, const RHS &R)
apfloat_match m_APFloat(const APFloat *&Res)
Match a ConstantFP or splatted ConstantVector, binding the specified pointer to the contained APFloat...
Definition: PatternMatch.h:295
BinaryOp_match< LHS, RHS, Instruction::SRem > m_SRem(const LHS &L, const RHS &R)
match_combine_or< CastClass_match< OpTy, Instruction::SExt >, OpTy > m_SExtOrSelf(const OpTy &Op)
BinaryOp_match< cst_pred_ty< is_all_ones >, ValTy, Instruction::Xor, true > m_Not(const ValTy &V)
Matches a 'Not' as 'xor V, -1' or 'xor -1, V'.
BinaryOp_match< LHS, RHS, Instruction::Or > m_Or(const LHS &L, const RHS &R)
is_zero m_Zero()
Match any null constant or a vector with all elements equal to 0.
Definition: PatternMatch.h:537
BinaryOp_match< LHS, RHS, Instruction::Or, true > m_c_Or(const LHS &L, const RHS &R)
Matches an Or with LHS and RHS in either order.
BinaryOp_match< LHS, RHS, Instruction::Mul, true > m_c_Mul(const LHS &L, const RHS &R)
Matches a Mul with LHS and RHS in either order.
m_Intrinsic_Ty< Opnd0, Opnd1 >::Ty m_CopySign(const Opnd0 &Op0, const Opnd1 &Op1)
BinaryOp_match< LHS, RHS, Instruction::Sub > m_Sub(const LHS &L, const RHS &R)
Definition: PatternMatch.h:991
MaxMin_match< ICmpInst, LHS, RHS, umin_pred_ty > m_UMin(const LHS &L, const RHS &R)
match_combine_or< LTy, RTy > m_CombineOr(const LTy &L, const RTy &R)
Combine two pattern matchers matching L || R.
Definition: PatternMatch.h:218
cst_pred_ty< icmp_pred_with_threshold > m_SpecificInt_ICMP(ICmpInst::Predicate Predicate, const APInt &Threshold)
Match an integer or vector with every element comparing 'pred' (eg/ne/...) to Threshold.
Definition: PatternMatch.h:598
@ CE
Windows NT (Windows on ARM)
This is an optimization pass for GlobalISel generic memory operations.
Definition: AddressRanges.h:18
Intrinsic::ID getInverseMinMaxIntrinsic(Intrinsic::ID MinMaxID)
@ Offset
Definition: DWP.cpp:406
bool isKnownNonZero(const Value *V, const DataLayout &DL, unsigned Depth=0, AssumptionCache *AC=nullptr, const Instruction *CxtI=nullptr, const DominatorTree *DT=nullptr, bool UseInstrInfo=true)
Return true if the given value is known to be non-zero when defined.
constexpr bool isInt(int64_t x)
Checks if an integer fits into the given bit width.
Definition: MathExtras.h:179
std::string & operator+=(std::string &buffer, StringRef string)
Definition: StringRef.h:890
Value * simplifySubInst(Value *LHS, Value *RHS, bool IsNSW, bool IsNUW, const SimplifyQuery &Q)
Given operands for a Sub, fold the result or return null.
Value * simplifyAddInst(Value *LHS, Value *RHS, bool IsNSW, bool IsNUW, const SimplifyQuery &Q)
Given operands for an Add, fold the result or return null.
Constant * ConstantFoldUnaryOpOperand(unsigned Opcode, Constant *Op, const DataLayout &DL)
Attempt to constant fold a unary operation with the specified operand.
Value * simplifyFNegInst(Value *Op, FastMathFlags FMF, const SimplifyQuery &Q)
Given operand for an FNeg, fold the result or return null.
Value * simplifyFSubInst(Value *LHS, Value *RHS, FastMathFlags FMF, const SimplifyQuery &Q, fp::ExceptionBehavior ExBehavior=fp::ebIgnore, RoundingMode Rounding=RoundingMode::NearestTiesToEven)
Given operands for an FSub, fold the result or return null.
decltype(auto) get(const PointerIntPair< PointerTy, IntBits, IntType, PtrTraits, Info > &Pair)
Value * simplifyFAddInst(Value *LHS, Value *RHS, FastMathFlags FMF, const SimplifyQuery &Q, fp::ExceptionBehavior ExBehavior=fp::ebIgnore, RoundingMode Rounding=RoundingMode::NearestTiesToEven)
Given operands for an FAdd, fold the result or return null.
bool none_of(R &&Range, UnaryPredicate P)
Provide wrappers to std::none_of which take ranges instead of having to pass begin/end explicitly.
Definition: STLExtras.h:1833
Constant * ConstantFoldBinaryOpOperands(unsigned Opcode, Constant *LHS, Constant *RHS, const DataLayout &DL)
Attempt to constant fold a binary operation with the specified operands.
bool haveNoCommonBitsSet(const Value *LHS, const Value *RHS, const DataLayout &DL, AssumptionCache *AC=nullptr, const Instruction *CxtI=nullptr, const DominatorTree *DT=nullptr, bool UseInstrInfo=true)
Return true if LHS and RHS have no common bits set.
@ Mul
Product of integers.
@ FMul
Product of floats.
@ And
Bitwise or logical AND of integers.
@ SMin
Signed integer min implemented in terms of select(cmp()).
@ Add
Sum of integers.
@ FAdd
Sum of floats.
RoundingMode
Rounding mode.
bool isGuaranteedNotToBeUndefOrPoison(const Value *V, AssumptionCache *AC=nullptr, const Instruction *CtxI=nullptr, const DominatorTree *DT=nullptr, unsigned Depth=0)
Return true if this function can prove that V does not have undef bits and is never poison.
constexpr unsigned BitWidth
Definition: BitmaskEnum.h:184
bool CannotBeNegativeZero(const Value *V, const TargetLibraryInfo *TLI, unsigned Depth=0)
Return true if we can prove that the specified FP value is never equal to -0.0.
void swap(llvm::BitVector &LHS, llvm::BitVector &RHS)
Implement std::swap in terms of BitVector swap.
Definition: BitVector.h:860
static unsigned int semanticsPrecision(const fltSemantics &)
Definition: APFloat.cpp:304
A suitably aligned and sized character array member which can hold elements of any type.
Definition: AlignOf.h:27
const Instruction * CxtI
const DominatorTree * DT
AssumptionCache * AC
SimplifyQuery getWithInstruction(Instruction *I) const
const TargetLibraryInfo * TLI