LLVM  4.0.0
InstCombineAndOrXor.cpp
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1 //===- InstCombineAndOrXor.cpp --------------------------------------------===//
2 //
3 // The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // This file implements the visitAnd, visitOr, and visitXor functions.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #include "InstCombineInternal.h"
16 #include "llvm/IR/ConstantRange.h"
17 #include "llvm/IR/Intrinsics.h"
18 #include "llvm/IR/PatternMatch.h"
21 using namespace llvm;
22 using namespace PatternMatch;
23 
24 #define DEBUG_TYPE "instcombine"
25 
26 static inline Value *dyn_castNotVal(Value *V) {
27  // If this is not(not(x)) don't return that this is a not: we want the two
28  // not's to be folded first.
29  if (BinaryOperator::isNot(V)) {
31  if (!IsFreeToInvert(Operand, Operand->hasOneUse()))
32  return Operand;
33  }
34 
35  // Constants can be considered to be not'ed values...
36  if (ConstantInt *C = dyn_cast<ConstantInt>(V))
37  return ConstantInt::get(C->getType(), ~C->getValue());
38  return nullptr;
39 }
40 
41 /// Similar to getICmpCode but for FCmpInst. This encodes a fcmp predicate into
42 /// a four bit mask.
43 static unsigned getFCmpCode(FCmpInst::Predicate CC) {
45  "Unexpected FCmp predicate!");
46  // Take advantage of the bit pattern of FCmpInst::Predicate here.
47  // U L G E
48  static_assert(FCmpInst::FCMP_FALSE == 0, ""); // 0 0 0 0
49  static_assert(FCmpInst::FCMP_OEQ == 1, ""); // 0 0 0 1
50  static_assert(FCmpInst::FCMP_OGT == 2, ""); // 0 0 1 0
51  static_assert(FCmpInst::FCMP_OGE == 3, ""); // 0 0 1 1
52  static_assert(FCmpInst::FCMP_OLT == 4, ""); // 0 1 0 0
53  static_assert(FCmpInst::FCMP_OLE == 5, ""); // 0 1 0 1
54  static_assert(FCmpInst::FCMP_ONE == 6, ""); // 0 1 1 0
55  static_assert(FCmpInst::FCMP_ORD == 7, ""); // 0 1 1 1
56  static_assert(FCmpInst::FCMP_UNO == 8, ""); // 1 0 0 0
57  static_assert(FCmpInst::FCMP_UEQ == 9, ""); // 1 0 0 1
58  static_assert(FCmpInst::FCMP_UGT == 10, ""); // 1 0 1 0
59  static_assert(FCmpInst::FCMP_UGE == 11, ""); // 1 0 1 1
60  static_assert(FCmpInst::FCMP_ULT == 12, ""); // 1 1 0 0
61  static_assert(FCmpInst::FCMP_ULE == 13, ""); // 1 1 0 1
62  static_assert(FCmpInst::FCMP_UNE == 14, ""); // 1 1 1 0
63  static_assert(FCmpInst::FCMP_TRUE == 15, ""); // 1 1 1 1
64  return CC;
65 }
66 
67 /// This is the complement of getICmpCode, which turns an opcode and two
68 /// operands into either a constant true or false, or a brand new ICmp
69 /// instruction. The sign is passed in to determine which kind of predicate to
70 /// use in the new icmp instruction.
71 static Value *getNewICmpValue(bool Sign, unsigned Code, Value *LHS, Value *RHS,
72  InstCombiner::BuilderTy *Builder) {
73  ICmpInst::Predicate NewPred;
74  if (Value *NewConstant = getICmpValue(Sign, Code, LHS, RHS, NewPred))
75  return NewConstant;
76  return Builder->CreateICmp(NewPred, LHS, RHS);
77 }
78 
79 /// This is the complement of getFCmpCode, which turns an opcode and two
80 /// operands into either a FCmp instruction, or a true/false constant.
81 static Value *getFCmpValue(unsigned Code, Value *LHS, Value *RHS,
82  InstCombiner::BuilderTy *Builder) {
83  const auto Pred = static_cast<FCmpInst::Predicate>(Code);
84  assert(FCmpInst::FCMP_FALSE <= Pred && Pred <= FCmpInst::FCMP_TRUE &&
85  "Unexpected FCmp predicate!");
86  if (Pred == FCmpInst::FCMP_FALSE)
88  if (Pred == FCmpInst::FCMP_TRUE)
90  return Builder->CreateFCmp(Pred, LHS, RHS);
91 }
92 
93 /// \brief Transform BITWISE_OP(BSWAP(A),BSWAP(B)) to BSWAP(BITWISE_OP(A, B))
94 /// \param I Binary operator to transform.
95 /// \return Pointer to node that must replace the original binary operator, or
96 /// null pointer if no transformation was made.
97 Value *InstCombiner::SimplifyBSwap(BinaryOperator &I) {
99 
100  // Can't do vectors.
101  if (I.getType()->isVectorTy())
102  return nullptr;
103 
104  // Can only do bitwise ops.
105  if (!I.isBitwiseLogicOp())
106  return nullptr;
107 
108  Value *OldLHS = I.getOperand(0);
109  Value *OldRHS = I.getOperand(1);
110  ConstantInt *ConstLHS = dyn_cast<ConstantInt>(OldLHS);
111  ConstantInt *ConstRHS = dyn_cast<ConstantInt>(OldRHS);
112  IntrinsicInst *IntrLHS = dyn_cast<IntrinsicInst>(OldLHS);
113  IntrinsicInst *IntrRHS = dyn_cast<IntrinsicInst>(OldRHS);
114  bool IsBswapLHS = (IntrLHS && IntrLHS->getIntrinsicID() == Intrinsic::bswap);
115  bool IsBswapRHS = (IntrRHS && IntrRHS->getIntrinsicID() == Intrinsic::bswap);
116 
117  if (!IsBswapLHS && !IsBswapRHS)
118  return nullptr;
119 
120  if (!IsBswapLHS && !ConstLHS)
121  return nullptr;
122 
123  if (!IsBswapRHS && !ConstRHS)
124  return nullptr;
125 
126  /// OP( BSWAP(x), BSWAP(y) ) -> BSWAP( OP(x, y) )
127  /// OP( BSWAP(x), CONSTANT ) -> BSWAP( OP(x, BSWAP(CONSTANT) ) )
128  Value *NewLHS = IsBswapLHS ? IntrLHS->getOperand(0) :
129  Builder->getInt(ConstLHS->getValue().byteSwap());
130 
131  Value *NewRHS = IsBswapRHS ? IntrRHS->getOperand(0) :
132  Builder->getInt(ConstRHS->getValue().byteSwap());
133 
134  Value *BinOp = Builder->CreateBinOp(I.getOpcode(), NewLHS, NewRHS);
135  Function *F = Intrinsic::getDeclaration(I.getModule(), Intrinsic::bswap, ITy);
136  return Builder->CreateCall(F, BinOp);
137 }
138 
139 /// This handles expressions of the form ((val OP C1) & C2). Where
140 /// the Op parameter is 'OP', OpRHS is 'C1', and AndRHS is 'C2'. Op is
141 /// guaranteed to be a binary operator.
142 Instruction *InstCombiner::OptAndOp(Instruction *Op,
143  ConstantInt *OpRHS,
144  ConstantInt *AndRHS,
145  BinaryOperator &TheAnd) {
146  Value *X = Op->getOperand(0);
147  Constant *Together = nullptr;
148  if (!Op->isShift())
149  Together = ConstantExpr::getAnd(AndRHS, OpRHS);
150 
151  switch (Op->getOpcode()) {
152  case Instruction::Xor:
153  if (Op->hasOneUse()) {
154  // (X ^ C1) & C2 --> (X & C2) ^ (C1&C2)
155  Value *And = Builder->CreateAnd(X, AndRHS);
156  And->takeName(Op);
157  return BinaryOperator::CreateXor(And, Together);
158  }
159  break;
160  case Instruction::Or:
161  if (Op->hasOneUse()){
162  if (Together != OpRHS) {
163  // (X | C1) & C2 --> (X | (C1&C2)) & C2
164  Value *Or = Builder->CreateOr(X, Together);
165  Or->takeName(Op);
166  return BinaryOperator::CreateAnd(Or, AndRHS);
167  }
168 
169  ConstantInt *TogetherCI = dyn_cast<ConstantInt>(Together);
170  if (TogetherCI && !TogetherCI->isZero()){
171  // (X | C1) & C2 --> (X & (C2^(C1&C2))) | C1
172  // NOTE: This reduces the number of bits set in the & mask, which
173  // can expose opportunities for store narrowing.
174  Together = ConstantExpr::getXor(AndRHS, Together);
175  Value *And = Builder->CreateAnd(X, Together);
176  And->takeName(Op);
177  return BinaryOperator::CreateOr(And, OpRHS);
178  }
179  }
180 
181  break;
182  case Instruction::Add:
183  if (Op->hasOneUse()) {
184  // Adding a one to a single bit bit-field should be turned into an XOR
185  // of the bit. First thing to check is to see if this AND is with a
186  // single bit constant.
187  const APInt &AndRHSV = AndRHS->getValue();
188 
189  // If there is only one bit set.
190  if (AndRHSV.isPowerOf2()) {
191  // Ok, at this point, we know that we are masking the result of the
192  // ADD down to exactly one bit. If the constant we are adding has
193  // no bits set below this bit, then we can eliminate the ADD.
194  const APInt& AddRHS = OpRHS->getValue();
195 
196  // Check to see if any bits below the one bit set in AndRHSV are set.
197  if ((AddRHS & (AndRHSV-1)) == 0) {
198  // If not, the only thing that can effect the output of the AND is
199  // the bit specified by AndRHSV. If that bit is set, the effect of
200  // the XOR is to toggle the bit. If it is clear, then the ADD has
201  // no effect.
202  if ((AddRHS & AndRHSV) == 0) { // Bit is not set, noop
203  TheAnd.setOperand(0, X);
204  return &TheAnd;
205  } else {
206  // Pull the XOR out of the AND.
207  Value *NewAnd = Builder->CreateAnd(X, AndRHS);
208  NewAnd->takeName(Op);
209  return BinaryOperator::CreateXor(NewAnd, AndRHS);
210  }
211  }
212  }
213  }
214  break;
215 
216  case Instruction::Shl: {
217  // We know that the AND will not produce any of the bits shifted in, so if
218  // the anded constant includes them, clear them now!
219  //
220  uint32_t BitWidth = AndRHS->getType()->getBitWidth();
221  uint32_t OpRHSVal = OpRHS->getLimitedValue(BitWidth);
222  APInt ShlMask(APInt::getHighBitsSet(BitWidth, BitWidth-OpRHSVal));
223  ConstantInt *CI = Builder->getInt(AndRHS->getValue() & ShlMask);
224 
225  if (CI->getValue() == ShlMask)
226  // Masking out bits that the shift already masks.
227  return replaceInstUsesWith(TheAnd, Op); // No need for the and.
228 
229  if (CI != AndRHS) { // Reducing bits set in and.
230  TheAnd.setOperand(1, CI);
231  return &TheAnd;
232  }
233  break;
234  }
235  case Instruction::LShr: {
236  // We know that the AND will not produce any of the bits shifted in, so if
237  // the anded constant includes them, clear them now! This only applies to
238  // unsigned shifts, because a signed shr may bring in set bits!
239  //
240  uint32_t BitWidth = AndRHS->getType()->getBitWidth();
241  uint32_t OpRHSVal = OpRHS->getLimitedValue(BitWidth);
242  APInt ShrMask(APInt::getLowBitsSet(BitWidth, BitWidth - OpRHSVal));
243  ConstantInt *CI = Builder->getInt(AndRHS->getValue() & ShrMask);
244 
245  if (CI->getValue() == ShrMask)
246  // Masking out bits that the shift already masks.
247  return replaceInstUsesWith(TheAnd, Op);
248 
249  if (CI != AndRHS) {
250  TheAnd.setOperand(1, CI); // Reduce bits set in and cst.
251  return &TheAnd;
252  }
253  break;
254  }
255  case Instruction::AShr:
256  // Signed shr.
257  // See if this is shifting in some sign extension, then masking it out
258  // with an and.
259  if (Op->hasOneUse()) {
260  uint32_t BitWidth = AndRHS->getType()->getBitWidth();
261  uint32_t OpRHSVal = OpRHS->getLimitedValue(BitWidth);
262  APInt ShrMask(APInt::getLowBitsSet(BitWidth, BitWidth - OpRHSVal));
263  Constant *C = Builder->getInt(AndRHS->getValue() & ShrMask);
264  if (C == AndRHS) { // Masking out bits shifted in.
265  // (Val ashr C1) & C2 -> (Val lshr C1) & C2
266  // Make the argument unsigned.
267  Value *ShVal = Op->getOperand(0);
268  ShVal = Builder->CreateLShr(ShVal, OpRHS, Op->getName());
269  return BinaryOperator::CreateAnd(ShVal, AndRHS, TheAnd.getName());
270  }
271  }
272  break;
273  }
274  return nullptr;
275 }
276 
277 /// Emit a computation of: (V >= Lo && V < Hi) if Inside is true, otherwise
278 /// (V < Lo || V >= Hi). This method expects that Lo <= Hi. IsSigned indicates
279 /// whether to treat V, Lo, and Hi as signed or not.
280 Value *InstCombiner::insertRangeTest(Value *V, const APInt &Lo, const APInt &Hi,
281  bool isSigned, bool Inside) {
282  assert((isSigned ? Lo.sle(Hi) : Lo.ule(Hi)) &&
283  "Lo is not <= Hi in range emission code!");
284 
285  Type *Ty = V->getType();
286  if (Lo == Hi)
287  return Inside ? ConstantInt::getFalse(Ty) : ConstantInt::getTrue(Ty);
288 
289  // V >= Min && V < Hi --> V < Hi
290  // V < Min || V >= Hi --> V >= Hi
292  if (isSigned ? Lo.isMinSignedValue() : Lo.isMinValue()) {
293  Pred = isSigned ? ICmpInst::getSignedPredicate(Pred) : Pred;
294  return Builder->CreateICmp(Pred, V, ConstantInt::get(Ty, Hi));
295  }
296 
297  // V >= Lo && V < Hi --> V - Lo u< Hi - Lo
298  // V < Lo || V >= Hi --> V - Lo u>= Hi - Lo
299  Value *VMinusLo =
300  Builder->CreateSub(V, ConstantInt::get(Ty, Lo), V->getName() + ".off");
301  Constant *HiMinusLo = ConstantInt::get(Ty, Hi - Lo);
302  return Builder->CreateICmp(Pred, VMinusLo, HiMinusLo);
303 }
304 
305 /// Returns true iff Val consists of one contiguous run of 1s with any number
306 /// of 0s on either side. The 1s are allowed to wrap from LSB to MSB,
307 /// so 0x000FFF0, 0x0000FFFF, and 0xFF0000FF are all runs. 0x0F0F0000 is
308 /// not, since all 1s are not contiguous.
309 static bool isRunOfOnes(ConstantInt *Val, uint32_t &MB, uint32_t &ME) {
310  const APInt& V = Val->getValue();
311  uint32_t BitWidth = Val->getType()->getBitWidth();
312  if (!APIntOps::isShiftedMask(BitWidth, V)) return false;
313 
314  // look for the first zero bit after the run of ones
315  MB = BitWidth - ((V - 1) ^ V).countLeadingZeros();
316  // look for the first non-zero bit
317  ME = V.getActiveBits();
318  return true;
319 }
320 
321 /// This is part of an expression (LHS +/- RHS) & Mask, where isSub determines
322 /// whether the operator is a sub. If we can fold one of the following xforms:
323 ///
324 /// ((A & N) +/- B) & Mask -> (A +/- B) & Mask iff N&Mask == Mask
325 /// ((A | N) +/- B) & Mask -> (A +/- B) & Mask iff N&Mask == 0
326 /// ((A ^ N) +/- B) & Mask -> (A +/- B) & Mask iff N&Mask == 0
327 ///
328 /// return (A +/- B).
329 ///
330 Value *InstCombiner::FoldLogicalPlusAnd(Value *LHS, Value *RHS,
331  ConstantInt *Mask, bool isSub,
332  Instruction &I) {
333  Instruction *LHSI = dyn_cast<Instruction>(LHS);
334  if (!LHSI || LHSI->getNumOperands() != 2 ||
335  !isa<ConstantInt>(LHSI->getOperand(1))) return nullptr;
336 
337  ConstantInt *N = cast<ConstantInt>(LHSI->getOperand(1));
338 
339  switch (LHSI->getOpcode()) {
340  default: return nullptr;
341  case Instruction::And:
342  if (ConstantExpr::getAnd(N, Mask) == Mask) {
343  // If the AndRHS is a power of two minus one (0+1+), this is simple.
344  if ((Mask->getValue().countLeadingZeros() +
345  Mask->getValue().countPopulation()) ==
346  Mask->getValue().getBitWidth())
347  break;
348 
349  // Otherwise, if Mask is 0+1+0+, and if B is known to have the low 0+
350  // part, we don't need any explicit masks to take them out of A. If that
351  // is all N is, ignore it.
352  uint32_t MB = 0, ME = 0;
353  if (isRunOfOnes(Mask, MB, ME)) { // begin/end bit of run, inclusive
354  uint32_t BitWidth = cast<IntegerType>(RHS->getType())->getBitWidth();
355  APInt Mask(APInt::getLowBitsSet(BitWidth, MB-1));
356  if (MaskedValueIsZero(RHS, Mask, 0, &I))
357  break;
358  }
359  }
360  return nullptr;
361  case Instruction::Or:
362  case Instruction::Xor:
363  // If the AndRHS is a power of two minus one (0+1+), and N&Mask == 0
364  if ((Mask->getValue().countLeadingZeros() +
365  Mask->getValue().countPopulation()) == Mask->getValue().getBitWidth()
366  && ConstantExpr::getAnd(N, Mask)->isNullValue())
367  break;
368  return nullptr;
369  }
370 
371  if (isSub)
372  return Builder->CreateSub(LHSI->getOperand(0), RHS, "fold");
373  return Builder->CreateAdd(LHSI->getOperand(0), RHS, "fold");
374 }
375 
376 /// enum for classifying (icmp eq (A & B), C) and (icmp ne (A & B), C)
377 /// One of A and B is considered the mask, the other the value. This is
378 /// described as the "AMask" or "BMask" part of the enum. If the enum
379 /// contains only "Mask", then both A and B can be considered masks.
380 /// If A is the mask, then it was proven, that (A & C) == C. This
381 /// is trivial if C == A, or C == 0. If both A and C are constants, this
382 /// proof is also easy.
383 /// For the following explanations we assume that A is the mask.
384 /// The part "AllOnes" declares, that the comparison is true only
385 /// if (A & B) == A, or all bits of A are set in B.
386 /// Example: (icmp eq (A & 3), 3) -> FoldMskICmp_AMask_AllOnes
387 /// The part "AllZeroes" declares, that the comparison is true only
388 /// if (A & B) == 0, or all bits of A are cleared in B.
389 /// Example: (icmp eq (A & 3), 0) -> FoldMskICmp_Mask_AllZeroes
390 /// The part "Mixed" declares, that (A & B) == C and C might or might not
391 /// contain any number of one bits and zero bits.
392 /// Example: (icmp eq (A & 3), 1) -> FoldMskICmp_AMask_Mixed
393 /// The Part "Not" means, that in above descriptions "==" should be replaced
394 /// by "!=".
395 /// Example: (icmp ne (A & 3), 3) -> FoldMskICmp_AMask_NotAllOnes
396 /// If the mask A contains a single bit, then the following is equivalent:
397 /// (icmp eq (A & B), A) equals (icmp ne (A & B), 0)
398 /// (icmp ne (A & B), A) equals (icmp eq (A & B), 0)
410 };
411 
412 /// Return the set of pattern classes (from MaskedICmpType)
413 /// that (icmp SCC (A & B), C) satisfies.
414 static unsigned getTypeOfMaskedICmp(Value* A, Value* B, Value* C,
416 {
417  ConstantInt *ACst = dyn_cast<ConstantInt>(A);
418  ConstantInt *BCst = dyn_cast<ConstantInt>(B);
419  ConstantInt *CCst = dyn_cast<ConstantInt>(C);
420  bool icmp_eq = (SCC == ICmpInst::ICMP_EQ);
421  bool icmp_abit = (ACst && !ACst->isZero() &&
422  ACst->getValue().isPowerOf2());
423  bool icmp_bbit = (BCst && !BCst->isZero() &&
424  BCst->getValue().isPowerOf2());
425  unsigned result = 0;
426  if (CCst && CCst->isZero()) {
427  // if C is zero, then both A and B qualify as mask
428  result |= (icmp_eq ? (FoldMskICmp_Mask_AllZeroes |
434  if (icmp_abit)
435  result |= (icmp_eq ? (FoldMskICmp_AMask_NotAllOnes |
439  if (icmp_bbit)
440  result |= (icmp_eq ? (FoldMskICmp_BMask_NotAllOnes |
444  return result;
445  }
446  if (A == C) {
447  result |= (icmp_eq ? (FoldMskICmp_AMask_AllOnes |
451  if (icmp_abit)
452  result |= (icmp_eq ? (FoldMskICmp_Mask_NotAllZeroes |
456  } else if (ACst && CCst &&
457  ConstantExpr::getAnd(ACst, CCst) == CCst) {
458  result |= (icmp_eq ? FoldMskICmp_AMask_Mixed
460  }
461  if (B == C) {
462  result |= (icmp_eq ? (FoldMskICmp_BMask_AllOnes |
466  if (icmp_bbit)
467  result |= (icmp_eq ? (FoldMskICmp_Mask_NotAllZeroes |
471  } else if (BCst && CCst &&
472  ConstantExpr::getAnd(BCst, CCst) == CCst) {
473  result |= (icmp_eq ? FoldMskICmp_BMask_Mixed
475  }
476  return result;
477 }
478 
479 /// Convert an analysis of a masked ICmp into its equivalent if all boolean
480 /// operations had the opposite sense. Since each "NotXXX" flag (recording !=)
481 /// is adjacent to the corresponding normal flag (recording ==), this just
482 /// involves swapping those bits over.
483 static unsigned conjugateICmpMask(unsigned Mask) {
484  unsigned NewMask;
488  << 1;
489 
490  NewMask |=
494  >> 1;
495 
496  return NewMask;
497 }
498 
499 /// Handle (icmp(A & B) ==/!= C) &/| (icmp(A & D) ==/!= E)
500 /// Return the set of pattern classes (from MaskedICmpType)
501 /// that both LHS and RHS satisfy.
503  Value*& B, Value*& C,
504  Value*& D, Value*& E,
505  ICmpInst *LHS, ICmpInst *RHS,
506  ICmpInst::Predicate &LHSCC,
507  ICmpInst::Predicate &RHSCC) {
508  if (LHS->getOperand(0)->getType() != RHS->getOperand(0)->getType()) return 0;
509  // vectors are not (yet?) supported
510  if (LHS->getOperand(0)->getType()->isVectorTy()) return 0;
511 
512  // Here comes the tricky part:
513  // LHS might be of the form L11 & L12 == X, X == L21 & L22,
514  // and L11 & L12 == L21 & L22. The same goes for RHS.
515  // Now we must find those components L** and R**, that are equal, so
516  // that we can extract the parameters A, B, C, D, and E for the canonical
517  // above.
518  Value *L1 = LHS->getOperand(0);
519  Value *L2 = LHS->getOperand(1);
520  Value *L11,*L12,*L21,*L22;
521  // Check whether the icmp can be decomposed into a bit test.
522  if (decomposeBitTestICmp(LHS, LHSCC, L11, L12, L2)) {
523  L21 = L22 = L1 = nullptr;
524  } else {
525  // Look for ANDs in the LHS icmp.
526  if (!L1->getType()->isIntegerTy()) {
527  // You can icmp pointers, for example. They really aren't masks.
528  L11 = L12 = nullptr;
529  } else if (!match(L1, m_And(m_Value(L11), m_Value(L12)))) {
530  // Any icmp can be viewed as being trivially masked; if it allows us to
531  // remove one, it's worth it.
532  L11 = L1;
533  L12 = Constant::getAllOnesValue(L1->getType());
534  }
535 
536  if (!L2->getType()->isIntegerTy()) {
537  // You can icmp pointers, for example. They really aren't masks.
538  L21 = L22 = nullptr;
539  } else if (!match(L2, m_And(m_Value(L21), m_Value(L22)))) {
540  L21 = L2;
541  L22 = Constant::getAllOnesValue(L2->getType());
542  }
543  }
544 
545  // Bail if LHS was a icmp that can't be decomposed into an equality.
546  if (!ICmpInst::isEquality(LHSCC))
547  return 0;
548 
549  Value *R1 = RHS->getOperand(0);
550  Value *R2 = RHS->getOperand(1);
551  Value *R11,*R12;
552  bool ok = false;
553  if (decomposeBitTestICmp(RHS, RHSCC, R11, R12, R2)) {
554  if (R11 == L11 || R11 == L12 || R11 == L21 || R11 == L22) {
555  A = R11; D = R12;
556  } else if (R12 == L11 || R12 == L12 || R12 == L21 || R12 == L22) {
557  A = R12; D = R11;
558  } else {
559  return 0;
560  }
561  E = R2; R1 = nullptr; ok = true;
562  } else if (R1->getType()->isIntegerTy()) {
563  if (!match(R1, m_And(m_Value(R11), m_Value(R12)))) {
564  // As before, model no mask as a trivial mask if it'll let us do an
565  // optimization.
566  R11 = R1;
567  R12 = Constant::getAllOnesValue(R1->getType());
568  }
569 
570  if (R11 == L11 || R11 == L12 || R11 == L21 || R11 == L22) {
571  A = R11; D = R12; E = R2; ok = true;
572  } else if (R12 == L11 || R12 == L12 || R12 == L21 || R12 == L22) {
573  A = R12; D = R11; E = R2; ok = true;
574  }
575  }
576 
577  // Bail if RHS was a icmp that can't be decomposed into an equality.
578  if (!ICmpInst::isEquality(RHSCC))
579  return 0;
580 
581  // Look for ANDs on the right side of the RHS icmp.
582  if (!ok && R2->getType()->isIntegerTy()) {
583  if (!match(R2, m_And(m_Value(R11), m_Value(R12)))) {
584  R11 = R2;
585  R12 = Constant::getAllOnesValue(R2->getType());
586  }
587 
588  if (R11 == L11 || R11 == L12 || R11 == L21 || R11 == L22) {
589  A = R11; D = R12; E = R1; ok = true;
590  } else if (R12 == L11 || R12 == L12 || R12 == L21 || R12 == L22) {
591  A = R12; D = R11; E = R1; ok = true;
592  } else {
593  return 0;
594  }
595  }
596  if (!ok)
597  return 0;
598 
599  if (L11 == A) {
600  B = L12; C = L2;
601  } else if (L12 == A) {
602  B = L11; C = L2;
603  } else if (L21 == A) {
604  B = L22; C = L1;
605  } else if (L22 == A) {
606  B = L21; C = L1;
607  }
608 
609  unsigned LeftType = getTypeOfMaskedICmp(A, B, C, LHSCC);
610  unsigned RightType = getTypeOfMaskedICmp(A, D, E, RHSCC);
611  return LeftType & RightType;
612 }
613 
614 /// Try to fold (icmp(A & B) ==/!= C) &/| (icmp(A & D) ==/!= E)
615 /// into a single (icmp(A & X) ==/!= Y).
616 static Value *foldLogOpOfMaskedICmps(ICmpInst *LHS, ICmpInst *RHS, bool IsAnd,
618  Value *A = nullptr, *B = nullptr, *C = nullptr, *D = nullptr, *E = nullptr;
619  ICmpInst::Predicate LHSCC = LHS->getPredicate(), RHSCC = RHS->getPredicate();
620  unsigned Mask = foldLogOpOfMaskedICmpsHelper(A, B, C, D, E, LHS, RHS,
621  LHSCC, RHSCC);
622  if (Mask == 0) return nullptr;
624  "foldLogOpOfMaskedICmpsHelper must return an equality predicate.");
625 
626  // In full generality:
627  // (icmp (A & B) Op C) | (icmp (A & D) Op E)
628  // == ![ (icmp (A & B) !Op C) & (icmp (A & D) !Op E) ]
629  //
630  // If the latter can be converted into (icmp (A & X) Op Y) then the former is
631  // equivalent to (icmp (A & X) !Op Y).
632  //
633  // Therefore, we can pretend for the rest of this function that we're dealing
634  // with the conjunction, provided we flip the sense of any comparisons (both
635  // input and output).
636 
637  // In most cases we're going to produce an EQ for the "&&" case.
639  if (!IsAnd) {
640  // Convert the masking analysis into its equivalent with negated
641  // comparisons.
642  Mask = conjugateICmpMask(Mask);
643  }
644 
645  if (Mask & FoldMskICmp_Mask_AllZeroes) {
646  // (icmp eq (A & B), 0) & (icmp eq (A & D), 0)
647  // -> (icmp eq (A & (B|D)), 0)
648  Value *NewOr = Builder->CreateOr(B, D);
649  Value *NewAnd = Builder->CreateAnd(A, NewOr);
650  // We can't use C as zero because we might actually handle
651  // (icmp ne (A & B), B) & (icmp ne (A & D), D)
652  // with B and D, having a single bit set.
654  return Builder->CreateICmp(NewCC, NewAnd, Zero);
655  }
656  if (Mask & FoldMskICmp_BMask_AllOnes) {
657  // (icmp eq (A & B), B) & (icmp eq (A & D), D)
658  // -> (icmp eq (A & (B|D)), (B|D))
659  Value *NewOr = Builder->CreateOr(B, D);
660  Value *NewAnd = Builder->CreateAnd(A, NewOr);
661  return Builder->CreateICmp(NewCC, NewAnd, NewOr);
662  }
663  if (Mask & FoldMskICmp_AMask_AllOnes) {
664  // (icmp eq (A & B), A) & (icmp eq (A & D), A)
665  // -> (icmp eq (A & (B&D)), A)
666  Value *NewAnd1 = Builder->CreateAnd(B, D);
667  Value *NewAnd2 = Builder->CreateAnd(A, NewAnd1);
668  return Builder->CreateICmp(NewCC, NewAnd2, A);
669  }
670 
671  // Remaining cases assume at least that B and D are constant, and depend on
672  // their actual values. This isn't strictly necessary, just a "handle the
673  // easy cases for now" decision.
674  ConstantInt *BCst = dyn_cast<ConstantInt>(B);
675  if (!BCst) return nullptr;
676  ConstantInt *DCst = dyn_cast<ConstantInt>(D);
677  if (!DCst) return nullptr;
678 
680  // (icmp ne (A & B), 0) & (icmp ne (A & D), 0) and
681  // (icmp ne (A & B), B) & (icmp ne (A & D), D)
682  // -> (icmp ne (A & B), 0) or (icmp ne (A & D), 0)
683  // Only valid if one of the masks is a superset of the other (check "B&D" is
684  // the same as either B or D).
685  APInt NewMask = BCst->getValue() & DCst->getValue();
686 
687  if (NewMask == BCst->getValue())
688  return LHS;
689  else if (NewMask == DCst->getValue())
690  return RHS;
691  }
692  if (Mask & FoldMskICmp_AMask_NotAllOnes) {
693  // (icmp ne (A & B), B) & (icmp ne (A & D), D)
694  // -> (icmp ne (A & B), A) or (icmp ne (A & D), A)
695  // Only valid if one of the masks is a superset of the other (check "B|D" is
696  // the same as either B or D).
697  APInt NewMask = BCst->getValue() | DCst->getValue();
698 
699  if (NewMask == BCst->getValue())
700  return LHS;
701  else if (NewMask == DCst->getValue())
702  return RHS;
703  }
704  if (Mask & FoldMskICmp_BMask_Mixed) {
705  // (icmp eq (A & B), C) & (icmp eq (A & D), E)
706  // We already know that B & C == C && D & E == E.
707  // If we can prove that (B & D) & (C ^ E) == 0, that is, the bits of
708  // C and E, which are shared by both the mask B and the mask D, don't
709  // contradict, then we can transform to
710  // -> (icmp eq (A & (B|D)), (C|E))
711  // Currently, we only handle the case of B, C, D, and E being constant.
712  // We can't simply use C and E because we might actually handle
713  // (icmp ne (A & B), B) & (icmp eq (A & D), D)
714  // with B and D, having a single bit set.
715  ConstantInt *CCst = dyn_cast<ConstantInt>(C);
716  if (!CCst) return nullptr;
717  ConstantInt *ECst = dyn_cast<ConstantInt>(E);
718  if (!ECst) return nullptr;
719  if (LHSCC != NewCC)
720  CCst = cast<ConstantInt>(ConstantExpr::getXor(BCst, CCst));
721  if (RHSCC != NewCC)
722  ECst = cast<ConstantInt>(ConstantExpr::getXor(DCst, ECst));
723  // If there is a conflict, we should actually return a false for the
724  // whole construct.
725  if (((BCst->getValue() & DCst->getValue()) &
726  (CCst->getValue() ^ ECst->getValue())) != 0)
727  return ConstantInt::get(LHS->getType(), !IsAnd);
728  Value *NewOr1 = Builder->CreateOr(B, D);
729  Value *NewOr2 = ConstantExpr::getOr(CCst, ECst);
730  Value *NewAnd = Builder->CreateAnd(A, NewOr1);
731  return Builder->CreateICmp(NewCC, NewAnd, NewOr2);
732  }
733  return nullptr;
734 }
735 
736 /// Try to fold a signed range checked with lower bound 0 to an unsigned icmp.
737 /// Example: (icmp sge x, 0) & (icmp slt x, n) --> icmp ult x, n
738 /// If \p Inverted is true then the check is for the inverted range, e.g.
739 /// (icmp slt x, 0) | (icmp sgt x, n) --> icmp ugt x, n
741  bool Inverted) {
742  // Check the lower range comparison, e.g. x >= 0
743  // InstCombine already ensured that if there is a constant it's on the RHS.
744  ConstantInt *RangeStart = dyn_cast<ConstantInt>(Cmp0->getOperand(1));
745  if (!RangeStart)
746  return nullptr;
747 
748  ICmpInst::Predicate Pred0 = (Inverted ? Cmp0->getInversePredicate() :
749  Cmp0->getPredicate());
750 
751  // Accept x > -1 or x >= 0 (after potentially inverting the predicate).
752  if (!((Pred0 == ICmpInst::ICMP_SGT && RangeStart->isMinusOne()) ||
753  (Pred0 == ICmpInst::ICMP_SGE && RangeStart->isZero())))
754  return nullptr;
755 
756  ICmpInst::Predicate Pred1 = (Inverted ? Cmp1->getInversePredicate() :
757  Cmp1->getPredicate());
758 
759  Value *Input = Cmp0->getOperand(0);
760  Value *RangeEnd;
761  if (Cmp1->getOperand(0) == Input) {
762  // For the upper range compare we have: icmp x, n
763  RangeEnd = Cmp1->getOperand(1);
764  } else if (Cmp1->getOperand(1) == Input) {
765  // For the upper range compare we have: icmp n, x
766  RangeEnd = Cmp1->getOperand(0);
767  Pred1 = ICmpInst::getSwappedPredicate(Pred1);
768  } else {
769  return nullptr;
770  }
771 
772  // Check the upper range comparison, e.g. x < n
773  ICmpInst::Predicate NewPred;
774  switch (Pred1) {
775  case ICmpInst::ICMP_SLT: NewPred = ICmpInst::ICMP_ULT; break;
776  case ICmpInst::ICMP_SLE: NewPred = ICmpInst::ICMP_ULE; break;
777  default: return nullptr;
778  }
779 
780  // This simplification is only valid if the upper range is not negative.
781  bool IsNegative, IsNotNegative;
782  ComputeSignBit(RangeEnd, IsNotNegative, IsNegative, /*Depth=*/0, Cmp1);
783  if (!IsNotNegative)
784  return nullptr;
785 
786  if (Inverted)
787  NewPred = ICmpInst::getInversePredicate(NewPred);
788 
789  return Builder->CreateICmp(NewPred, Input, RangeEnd);
790 }
791 
792 /// Fold (icmp)&(icmp) if possible.
794  ICmpInst::Predicate LHSCC = LHS->getPredicate(), RHSCC = RHS->getPredicate();
795 
796  // (icmp1 A, B) & (icmp2 A, B) --> (icmp3 A, B)
797  if (PredicatesFoldable(LHSCC, RHSCC)) {
798  if (LHS->getOperand(0) == RHS->getOperand(1) &&
799  LHS->getOperand(1) == RHS->getOperand(0))
800  LHS->swapOperands();
801  if (LHS->getOperand(0) == RHS->getOperand(0) &&
802  LHS->getOperand(1) == RHS->getOperand(1)) {
803  Value *Op0 = LHS->getOperand(0), *Op1 = LHS->getOperand(1);
804  unsigned Code = getICmpCode(LHS) & getICmpCode(RHS);
805  bool isSigned = LHS->isSigned() || RHS->isSigned();
806  return getNewICmpValue(isSigned, Code, Op0, Op1, Builder);
807  }
808  }
809 
810  // handle (roughly): (icmp eq (A & B), C) & (icmp eq (A & D), E)
811  if (Value *V = foldLogOpOfMaskedICmps(LHS, RHS, true, Builder))
812  return V;
813 
814  // E.g. (icmp sge x, 0) & (icmp slt x, n) --> icmp ult x, n
815  if (Value *V = simplifyRangeCheck(LHS, RHS, /*Inverted=*/false))
816  return V;
817 
818  // E.g. (icmp slt x, n) & (icmp sge x, 0) --> icmp ult x, n
819  if (Value *V = simplifyRangeCheck(RHS, LHS, /*Inverted=*/false))
820  return V;
821 
822  // This only handles icmp of constants: (icmp1 A, C1) & (icmp2 B, C2).
823  Value *Val = LHS->getOperand(0), *Val2 = RHS->getOperand(0);
824  ConstantInt *LHSCst = dyn_cast<ConstantInt>(LHS->getOperand(1));
825  ConstantInt *RHSCst = dyn_cast<ConstantInt>(RHS->getOperand(1));
826  if (!LHSCst || !RHSCst) return nullptr;
827 
828  if (LHSCst == RHSCst && LHSCC == RHSCC) {
829  // (icmp ult A, C) & (icmp ult B, C) --> (icmp ult (A|B), C)
830  // where C is a power of 2 or
831  // (icmp eq A, 0) & (icmp eq B, 0) --> (icmp eq (A|B), 0)
832  if ((LHSCC == ICmpInst::ICMP_ULT && LHSCst->getValue().isPowerOf2()) ||
833  (LHSCC == ICmpInst::ICMP_EQ && LHSCst->isZero())) {
834  Value *NewOr = Builder->CreateOr(Val, Val2);
835  return Builder->CreateICmp(LHSCC, NewOr, LHSCst);
836  }
837  }
838 
839  // (trunc x) == C1 & (and x, CA) == C2 -> (and x, CA|CMAX) == C1|C2
840  // where CMAX is the all ones value for the truncated type,
841  // iff the lower bits of C2 and CA are zero.
842  if (LHSCC == ICmpInst::ICMP_EQ && LHSCC == RHSCC &&
843  LHS->hasOneUse() && RHS->hasOneUse()) {
844  Value *V;
845  ConstantInt *AndCst, *SmallCst = nullptr, *BigCst = nullptr;
846 
847  // (trunc x) == C1 & (and x, CA) == C2
848  // (and x, CA) == C2 & (trunc x) == C1
849  if (match(Val2, m_Trunc(m_Value(V))) &&
850  match(Val, m_And(m_Specific(V), m_ConstantInt(AndCst)))) {
851  SmallCst = RHSCst;
852  BigCst = LHSCst;
853  } else if (match(Val, m_Trunc(m_Value(V))) &&
854  match(Val2, m_And(m_Specific(V), m_ConstantInt(AndCst)))) {
855  SmallCst = LHSCst;
856  BigCst = RHSCst;
857  }
858 
859  if (SmallCst && BigCst) {
860  unsigned BigBitSize = BigCst->getType()->getBitWidth();
861  unsigned SmallBitSize = SmallCst->getType()->getBitWidth();
862 
863  // Check that the low bits are zero.
864  APInt Low = APInt::getLowBitsSet(BigBitSize, SmallBitSize);
865  if ((Low & AndCst->getValue()) == 0 && (Low & BigCst->getValue()) == 0) {
866  Value *NewAnd = Builder->CreateAnd(V, Low | AndCst->getValue());
867  APInt N = SmallCst->getValue().zext(BigBitSize) | BigCst->getValue();
868  Value *NewVal = ConstantInt::get(AndCst->getType()->getContext(), N);
869  return Builder->CreateICmp(LHSCC, NewAnd, NewVal);
870  }
871  }
872  }
873 
874  // From here on, we only handle:
875  // (icmp1 A, C1) & (icmp2 A, C2) --> something simpler.
876  if (Val != Val2) return nullptr;
877 
878  // ICMP_[US][GL]E X, CST is folded to ICMP_[US][GL]T elsewhere.
879  if (LHSCC == ICmpInst::ICMP_UGE || LHSCC == ICmpInst::ICMP_ULE ||
880  RHSCC == ICmpInst::ICMP_UGE || RHSCC == ICmpInst::ICMP_ULE ||
881  LHSCC == ICmpInst::ICMP_SGE || LHSCC == ICmpInst::ICMP_SLE ||
882  RHSCC == ICmpInst::ICMP_SGE || RHSCC == ICmpInst::ICMP_SLE)
883  return nullptr;
884 
885  // We can't fold (ugt x, C) & (sgt x, C2).
886  if (!PredicatesFoldable(LHSCC, RHSCC))
887  return nullptr;
888 
889  // Ensure that the larger constant is on the RHS.
890  bool ShouldSwap;
891  if (CmpInst::isSigned(LHSCC) ||
892  (ICmpInst::isEquality(LHSCC) &&
893  CmpInst::isSigned(RHSCC)))
894  ShouldSwap = LHSCst->getValue().sgt(RHSCst->getValue());
895  else
896  ShouldSwap = LHSCst->getValue().ugt(RHSCst->getValue());
897 
898  if (ShouldSwap) {
899  std::swap(LHS, RHS);
900  std::swap(LHSCst, RHSCst);
901  std::swap(LHSCC, RHSCC);
902  }
903 
904  // At this point, we know we have two icmp instructions
905  // comparing a value against two constants and and'ing the result
906  // together. Because of the above check, we know that we only have
907  // icmp eq, icmp ne, icmp [su]lt, and icmp [SU]gt here. We also know
908  // (from the icmp folding check above), that the two constants
909  // are not equal and that the larger constant is on the RHS
910  assert(LHSCst != RHSCst && "Compares not folded above?");
911 
912  switch (LHSCC) {
913  default: llvm_unreachable("Unknown integer condition code!");
914  case ICmpInst::ICMP_EQ:
915  switch (RHSCC) {
916  default: llvm_unreachable("Unknown integer condition code!");
917  case ICmpInst::ICMP_NE: // (X == 13 & X != 15) -> X == 13
918  case ICmpInst::ICMP_ULT: // (X == 13 & X < 15) -> X == 13
919  case ICmpInst::ICMP_SLT: // (X == 13 & X < 15) -> X == 13
920  return LHS;
921  }
922  case ICmpInst::ICMP_NE:
923  switch (RHSCC) {
924  default: llvm_unreachable("Unknown integer condition code!");
925  case ICmpInst::ICMP_ULT:
926  if (LHSCst == SubOne(RHSCst)) // (X != 13 & X u< 14) -> X < 13
927  return Builder->CreateICmpULT(Val, LHSCst);
928  if (LHSCst->isNullValue()) // (X != 0 & X u< 14) -> X-1 u< 13
929  return insertRangeTest(Val, LHSCst->getValue() + 1, RHSCst->getValue(),
930  false, true);
931  break; // (X != 13 & X u< 15) -> no change
932  case ICmpInst::ICMP_SLT:
933  if (LHSCst == SubOne(RHSCst)) // (X != 13 & X s< 14) -> X < 13
934  return Builder->CreateICmpSLT(Val, LHSCst);
935  break; // (X != 13 & X s< 15) -> no change
936  case ICmpInst::ICMP_EQ: // (X != 13 & X == 15) -> X == 15
937  case ICmpInst::ICMP_UGT: // (X != 13 & X u> 15) -> X u> 15
938  case ICmpInst::ICMP_SGT: // (X != 13 & X s> 15) -> X s> 15
939  return RHS;
940  case ICmpInst::ICMP_NE:
941  // Special case to get the ordering right when the values wrap around
942  // zero.
943  if (LHSCst->getValue() == 0 && RHSCst->getValue().isAllOnesValue())
944  std::swap(LHSCst, RHSCst);
945  if (LHSCst == SubOne(RHSCst)){// (X != 13 & X != 14) -> X-13 >u 1
946  Constant *AddCST = ConstantExpr::getNeg(LHSCst);
947  Value *Add = Builder->CreateAdd(Val, AddCST, Val->getName()+".off");
948  return Builder->CreateICmpUGT(Add, ConstantInt::get(Add->getType(), 1),
949  Val->getName()+".cmp");
950  }
951  break; // (X != 13 & X != 15) -> no change
952  }
953  break;
954  case ICmpInst::ICMP_ULT:
955  switch (RHSCC) {
956  default: llvm_unreachable("Unknown integer condition code!");
957  case ICmpInst::ICMP_EQ: // (X u< 13 & X == 15) -> false
958  case ICmpInst::ICMP_UGT: // (X u< 13 & X u> 15) -> false
960  case ICmpInst::ICMP_SGT: // (X u< 13 & X s> 15) -> no change
961  break;
962  case ICmpInst::ICMP_NE: // (X u< 13 & X != 15) -> X u< 13
963  case ICmpInst::ICMP_ULT: // (X u< 13 & X u< 15) -> X u< 13
964  return LHS;
965  case ICmpInst::ICMP_SLT: // (X u< 13 & X s< 15) -> no change
966  break;
967  }
968  break;
969  case ICmpInst::ICMP_SLT:
970  switch (RHSCC) {
971  default: llvm_unreachable("Unknown integer condition code!");
972  case ICmpInst::ICMP_UGT: // (X s< 13 & X u> 15) -> no change
973  break;
974  case ICmpInst::ICMP_NE: // (X s< 13 & X != 15) -> X < 13
975  case ICmpInst::ICMP_SLT: // (X s< 13 & X s< 15) -> X < 13
976  return LHS;
977  case ICmpInst::ICMP_ULT: // (X s< 13 & X u< 15) -> no change
978  break;
979  }
980  break;
981  case ICmpInst::ICMP_UGT:
982  switch (RHSCC) {
983  default: llvm_unreachable("Unknown integer condition code!");
984  case ICmpInst::ICMP_EQ: // (X u> 13 & X == 15) -> X == 15
985  case ICmpInst::ICMP_UGT: // (X u> 13 & X u> 15) -> X u> 15
986  return RHS;
987  case ICmpInst::ICMP_SGT: // (X u> 13 & X s> 15) -> no change
988  break;
989  case ICmpInst::ICMP_NE:
990  if (RHSCst == AddOne(LHSCst)) // (X u> 13 & X != 14) -> X u> 14
991  return Builder->CreateICmp(LHSCC, Val, RHSCst);
992  break; // (X u> 13 & X != 15) -> no change
993  case ICmpInst::ICMP_ULT: // (X u> 13 & X u< 15) -> (X-14) <u 1
994  return insertRangeTest(Val, LHSCst->getValue() + 1, RHSCst->getValue(),
995  false, true);
996  case ICmpInst::ICMP_SLT: // (X u> 13 & X s< 15) -> no change
997  break;
998  }
999  break;
1000  case ICmpInst::ICMP_SGT:
1001  switch (RHSCC) {
1002  default: llvm_unreachable("Unknown integer condition code!");
1003  case ICmpInst::ICMP_EQ: // (X s> 13 & X == 15) -> X == 15
1004  case ICmpInst::ICMP_SGT: // (X s> 13 & X s> 15) -> X s> 15
1005  return RHS;
1006  case ICmpInst::ICMP_UGT: // (X s> 13 & X u> 15) -> no change
1007  break;
1008  case ICmpInst::ICMP_NE:
1009  if (RHSCst == AddOne(LHSCst)) // (X s> 13 & X != 14) -> X s> 14
1010  return Builder->CreateICmp(LHSCC, Val, RHSCst);
1011  break; // (X s> 13 & X != 15) -> no change
1012  case ICmpInst::ICMP_SLT: // (X s> 13 & X s< 15) -> (X-14) s< 1
1013  return insertRangeTest(Val, LHSCst->getValue() + 1, RHSCst->getValue(),
1014  true, true);
1015  case ICmpInst::ICMP_ULT: // (X s> 13 & X u< 15) -> no change
1016  break;
1017  }
1018  break;
1019  }
1020 
1021  return nullptr;
1022 }
1023 
1024 /// Optimize (fcmp)&(fcmp). NOTE: Unlike the rest of instcombine, this returns
1025 /// a Value which should already be inserted into the function.
1027  Value *Op0LHS = LHS->getOperand(0), *Op0RHS = LHS->getOperand(1);
1028  Value *Op1LHS = RHS->getOperand(0), *Op1RHS = RHS->getOperand(1);
1029  FCmpInst::Predicate Op0CC = LHS->getPredicate(), Op1CC = RHS->getPredicate();
1030 
1031  if (Op0LHS == Op1RHS && Op0RHS == Op1LHS) {
1032  // Swap RHS operands to match LHS.
1033  Op1CC = FCmpInst::getSwappedPredicate(Op1CC);
1034  std::swap(Op1LHS, Op1RHS);
1035  }
1036 
1037  // Simplify (fcmp cc0 x, y) & (fcmp cc1 x, y).
1038  // Suppose the relation between x and y is R, where R is one of
1039  // U(1000), L(0100), G(0010) or E(0001), and CC0 and CC1 are the bitmasks for
1040  // testing the desired relations.
1041  //
1042  // Since (R & CC0) and (R & CC1) are either R or 0, we actually have this:
1043  // bool(R & CC0) && bool(R & CC1)
1044  // = bool((R & CC0) & (R & CC1))
1045  // = bool(R & (CC0 & CC1)) <= by re-association, commutation, and idempotency
1046  if (Op0LHS == Op1LHS && Op0RHS == Op1RHS)
1047  return getFCmpValue(getFCmpCode(Op0CC) & getFCmpCode(Op1CC), Op0LHS, Op0RHS,
1048  Builder);
1049 
1050  if (LHS->getPredicate() == FCmpInst::FCMP_ORD &&
1051  RHS->getPredicate() == FCmpInst::FCMP_ORD) {
1052  if (LHS->getOperand(0)->getType() != RHS->getOperand(0)->getType())
1053  return nullptr;
1054 
1055  // (fcmp ord x, c) & (fcmp ord y, c) -> (fcmp ord x, y)
1056  if (ConstantFP *LHSC = dyn_cast<ConstantFP>(LHS->getOperand(1)))
1057  if (ConstantFP *RHSC = dyn_cast<ConstantFP>(RHS->getOperand(1))) {
1058  // If either of the constants are nans, then the whole thing returns
1059  // false.
1060  if (LHSC->getValueAPF().isNaN() || RHSC->getValueAPF().isNaN())
1061  return Builder->getFalse();
1062  return Builder->CreateFCmpORD(LHS->getOperand(0), RHS->getOperand(0));
1063  }
1064 
1065  // Handle vector zeros. This occurs because the canonical form of
1066  // "fcmp ord x,x" is "fcmp ord x, 0".
1067  if (isa<ConstantAggregateZero>(LHS->getOperand(1)) &&
1068  isa<ConstantAggregateZero>(RHS->getOperand(1)))
1069  return Builder->CreateFCmpORD(LHS->getOperand(0), RHS->getOperand(0));
1070  return nullptr;
1071  }
1072 
1073  return nullptr;
1074 }
1075 
1076 /// Match De Morgan's Laws:
1077 /// (~A & ~B) == (~(A | B))
1078 /// (~A | ~B) == (~(A & B))
1080  InstCombiner::BuilderTy *Builder) {
1081  auto Opcode = I.getOpcode();
1082  assert((Opcode == Instruction::And || Opcode == Instruction::Or) &&
1083  "Trying to match De Morgan's Laws with something other than and/or");
1084  // Flip the logic operation.
1085  if (Opcode == Instruction::And)
1086  Opcode = Instruction::Or;
1087  else
1088  Opcode = Instruction::And;
1089 
1090  Value *Op0 = I.getOperand(0);
1091  Value *Op1 = I.getOperand(1);
1092  // TODO: Use pattern matchers instead of dyn_cast.
1093  if (Value *Op0NotVal = dyn_castNotVal(Op0))
1094  if (Value *Op1NotVal = dyn_castNotVal(Op1))
1095  if (Op0->hasOneUse() && Op1->hasOneUse()) {
1096  Value *LogicOp = Builder->CreateBinOp(Opcode, Op0NotVal, Op1NotVal,
1097  I.getName() + ".demorgan");
1098  return BinaryOperator::CreateNot(LogicOp);
1099  }
1100 
1101  return nullptr;
1102 }
1103 
1104 bool InstCombiner::shouldOptimizeCast(CastInst *CI) {
1105  Value *CastSrc = CI->getOperand(0);
1106 
1107  // Noop casts and casts of constants should be eliminated trivially.
1108  if (CI->getSrcTy() == CI->getDestTy() || isa<Constant>(CastSrc))
1109  return false;
1110 
1111  // If this cast is paired with another cast that can be eliminated, we prefer
1112  // to have it eliminated.
1113  if (const auto *PrecedingCI = dyn_cast<CastInst>(CastSrc))
1114  if (isEliminableCastPair(PrecedingCI, CI))
1115  return false;
1116 
1117  // If this is a vector sext from a compare, then we don't want to break the
1118  // idiom where each element of the extended vector is either zero or all ones.
1119  if (CI->getOpcode() == Instruction::SExt &&
1120  isa<CmpInst>(CastSrc) && CI->getDestTy()->isVectorTy())
1121  return false;
1122 
1123  return true;
1124 }
1125 
1126 /// Fold {and,or,xor} (cast X), C.
1128  InstCombiner::BuilderTy *Builder) {
1129  Constant *C;
1130  if (!match(Logic.getOperand(1), m_Constant(C)))
1131  return nullptr;
1132 
1133  auto LogicOpc = Logic.getOpcode();
1134  Type *DestTy = Logic.getType();
1135  Type *SrcTy = Cast->getSrcTy();
1136 
1137  // If the first operand is bitcast, move the logic operation ahead of the
1138  // bitcast (do the logic operation in the original type). This can eliminate
1139  // bitcasts and allow combines that would otherwise be impeded by the bitcast.
1140  Value *X;
1141  if (match(Cast, m_BitCast(m_Value(X)))) {
1142  Value *NewConstant = ConstantExpr::getBitCast(C, SrcTy);
1143  Value *NewOp = Builder->CreateBinOp(LogicOpc, X, NewConstant);
1144  return CastInst::CreateBitOrPointerCast(NewOp, DestTy);
1145  }
1146 
1147  // Similarly, move the logic operation ahead of a zext if the constant is
1148  // unchanged in the smaller source type. Performing the logic in a smaller
1149  // type may provide more information to later folds, and the smaller logic
1150  // instruction may be cheaper (particularly in the case of vectors).
1151  if (match(Cast, m_OneUse(m_ZExt(m_Value(X))))) {
1152  Constant *TruncC = ConstantExpr::getTrunc(C, SrcTy);
1153  Constant *ZextTruncC = ConstantExpr::getZExt(TruncC, DestTy);
1154  if (ZextTruncC == C) {
1155  // LogicOpc (zext X), C --> zext (LogicOpc X, C)
1156  Value *NewOp = Builder->CreateBinOp(LogicOpc, X, TruncC);
1157  return new ZExtInst(NewOp, DestTy);
1158  }
1159  }
1160 
1161  return nullptr;
1162 }
1163 
1164 /// Fold {and,or,xor} (cast X), Y.
1165 Instruction *InstCombiner::foldCastedBitwiseLogic(BinaryOperator &I) {
1166  auto LogicOpc = I.getOpcode();
1167  assert(I.isBitwiseLogicOp() && "Unexpected opcode for bitwise logic folding");
1168 
1169  Value *Op0 = I.getOperand(0), *Op1 = I.getOperand(1);
1170  CastInst *Cast0 = dyn_cast<CastInst>(Op0);
1171  if (!Cast0)
1172  return nullptr;
1173 
1174  // This must be a cast from an integer or integer vector source type to allow
1175  // transformation of the logic operation to the source type.
1176  Type *DestTy = I.getType();
1177  Type *SrcTy = Cast0->getSrcTy();
1178  if (!SrcTy->isIntOrIntVectorTy())
1179  return nullptr;
1180 
1181  if (Instruction *Ret = foldLogicCastConstant(I, Cast0, Builder))
1182  return Ret;
1183 
1184  CastInst *Cast1 = dyn_cast<CastInst>(Op1);
1185  if (!Cast1)
1186  return nullptr;
1187 
1188  // Both operands of the logic operation are casts. The casts must be of the
1189  // same type for reduction.
1190  auto CastOpcode = Cast0->getOpcode();
1191  if (CastOpcode != Cast1->getOpcode() || SrcTy != Cast1->getSrcTy())
1192  return nullptr;
1193 
1194  Value *Cast0Src = Cast0->getOperand(0);
1195  Value *Cast1Src = Cast1->getOperand(0);
1196 
1197  // fold logic(cast(A), cast(B)) -> cast(logic(A, B))
1198  if (shouldOptimizeCast(Cast0) && shouldOptimizeCast(Cast1)) {
1199  Value *NewOp = Builder->CreateBinOp(LogicOpc, Cast0Src, Cast1Src,
1200  I.getName());
1201  return CastInst::Create(CastOpcode, NewOp, DestTy);
1202  }
1203 
1204  // For now, only 'and'/'or' have optimizations after this.
1205  if (LogicOpc == Instruction::Xor)
1206  return nullptr;
1207 
1208  // If this is logic(cast(icmp), cast(icmp)), try to fold this even if the
1209  // cast is otherwise not optimizable. This happens for vector sexts.
1210  ICmpInst *ICmp0 = dyn_cast<ICmpInst>(Cast0Src);
1211  ICmpInst *ICmp1 = dyn_cast<ICmpInst>(Cast1Src);
1212  if (ICmp0 && ICmp1) {
1213  Value *Res = LogicOpc == Instruction::And ? FoldAndOfICmps(ICmp0, ICmp1)
1214  : FoldOrOfICmps(ICmp0, ICmp1, &I);
1215  if (Res)
1216  return CastInst::Create(CastOpcode, Res, DestTy);
1217  return nullptr;
1218  }
1219 
1220  // If this is logic(cast(fcmp), cast(fcmp)), try to fold this even if the
1221  // cast is otherwise not optimizable. This happens for vector sexts.
1222  FCmpInst *FCmp0 = dyn_cast<FCmpInst>(Cast0Src);
1223  FCmpInst *FCmp1 = dyn_cast<FCmpInst>(Cast1Src);
1224  if (FCmp0 && FCmp1) {
1225  Value *Res = LogicOpc == Instruction::And ? FoldAndOfFCmps(FCmp0, FCmp1)
1226  : FoldOrOfFCmps(FCmp0, FCmp1);
1227  if (Res)
1228  return CastInst::Create(CastOpcode, Res, DestTy);
1229  return nullptr;
1230  }
1231 
1232  return nullptr;
1233 }
1234 
1236  Value *Op0 = I.getOperand(0), *Op1 = I.getOperand(1);
1237 
1238  // Canonicalize SExt or Not to the LHS
1239  if (match(Op1, m_SExt(m_Value())) || match(Op1, m_Not(m_Value()))) {
1240  std::swap(Op0, Op1);
1241  }
1242 
1243  // Fold (and (sext bool to A), B) --> (select bool, B, 0)
1244  Value *X = nullptr;
1245  if (match(Op0, m_SExt(m_Value(X))) &&
1246  X->getType()->getScalarType()->isIntegerTy(1)) {
1247  Value *Zero = Constant::getNullValue(Op1->getType());
1248  return SelectInst::Create(X, Op1, Zero);
1249  }
1250 
1251  // Fold (and ~(sext bool to A), B) --> (select bool, 0, B)
1252  if (match(Op0, m_Not(m_SExt(m_Value(X)))) &&
1253  X->getType()->getScalarType()->isIntegerTy(1)) {
1255  return SelectInst::Create(X, Zero, Op1);
1256  }
1257 
1258  return nullptr;
1259 }
1260 
1261 // FIXME: We use commutative matchers (m_c_*) for some, but not all, matches
1262 // here. We should standardize that construct where it is needed or choose some
1263 // other way to ensure that commutated variants of patterns are not missed.
1265  bool Changed = SimplifyAssociativeOrCommutative(I);
1266  Value *Op0 = I.getOperand(0), *Op1 = I.getOperand(1);
1267 
1268  if (Value *V = SimplifyVectorOp(I))
1269  return replaceInstUsesWith(I, V);
1270 
1271  if (Value *V = SimplifyAndInst(Op0, Op1, DL, &TLI, &DT, &AC))
1272  return replaceInstUsesWith(I, V);
1273 
1274  // (A|B)&(A|C) -> A|(B&C) etc
1275  if (Value *V = SimplifyUsingDistributiveLaws(I))
1276  return replaceInstUsesWith(I, V);
1277 
1278  // See if we can simplify any instructions used by the instruction whose sole
1279  // purpose is to compute bits we don't care about.
1280  if (SimplifyDemandedInstructionBits(I))
1281  return &I;
1282 
1283  if (Value *V = SimplifyBSwap(I))
1284  return replaceInstUsesWith(I, V);
1285 
1286  if (ConstantInt *AndRHS = dyn_cast<ConstantInt>(Op1)) {
1287  const APInt &AndRHSMask = AndRHS->getValue();
1288 
1289  // Optimize a variety of ((val OP C1) & C2) combinations...
1290  if (BinaryOperator *Op0I = dyn_cast<BinaryOperator>(Op0)) {
1291  Value *Op0LHS = Op0I->getOperand(0);
1292  Value *Op0RHS = Op0I->getOperand(1);
1293  switch (Op0I->getOpcode()) {
1294  default: break;
1295  case Instruction::Xor:
1296  case Instruction::Or: {
1297  // If the mask is only needed on one incoming arm, push it up.
1298  if (!Op0I->hasOneUse()) break;
1299 
1300  APInt NotAndRHS(~AndRHSMask);
1301  if (MaskedValueIsZero(Op0LHS, NotAndRHS, 0, &I)) {
1302  // Not masking anything out for the LHS, move to RHS.
1303  Value *NewRHS = Builder->CreateAnd(Op0RHS, AndRHS,
1304  Op0RHS->getName()+".masked");
1305  return BinaryOperator::Create(Op0I->getOpcode(), Op0LHS, NewRHS);
1306  }
1307  if (!isa<Constant>(Op0RHS) &&
1308  MaskedValueIsZero(Op0RHS, NotAndRHS, 0, &I)) {
1309  // Not masking anything out for the RHS, move to LHS.
1310  Value *NewLHS = Builder->CreateAnd(Op0LHS, AndRHS,
1311  Op0LHS->getName()+".masked");
1312  return BinaryOperator::Create(Op0I->getOpcode(), NewLHS, Op0RHS);
1313  }
1314 
1315  break;
1316  }
1317  case Instruction::Add:
1318  // ((A & N) + B) & AndRHS -> (A + B) & AndRHS iff N&AndRHS == AndRHS.
1319  // ((A | N) + B) & AndRHS -> (A + B) & AndRHS iff N&AndRHS == 0
1320  // ((A ^ N) + B) & AndRHS -> (A + B) & AndRHS iff N&AndRHS == 0
1321  if (Value *V = FoldLogicalPlusAnd(Op0LHS, Op0RHS, AndRHS, false, I))
1322  return BinaryOperator::CreateAnd(V, AndRHS);
1323  if (Value *V = FoldLogicalPlusAnd(Op0RHS, Op0LHS, AndRHS, false, I))
1324  return BinaryOperator::CreateAnd(V, AndRHS); // Add commutes
1325  break;
1326 
1327  case Instruction::Sub:
1328  // ((A & N) - B) & AndRHS -> (A - B) & AndRHS iff N&AndRHS == AndRHS.
1329  // ((A | N) - B) & AndRHS -> (A - B) & AndRHS iff N&AndRHS == 0
1330  // ((A ^ N) - B) & AndRHS -> (A - B) & AndRHS iff N&AndRHS == 0
1331  if (Value *V = FoldLogicalPlusAnd(Op0LHS, Op0RHS, AndRHS, true, I))
1332  return BinaryOperator::CreateAnd(V, AndRHS);
1333 
1334  // -x & 1 -> x & 1
1335  if (AndRHSMask == 1 && match(Op0LHS, m_Zero()))
1336  return BinaryOperator::CreateAnd(Op0RHS, AndRHS);
1337 
1338  // (A - N) & AndRHS -> -N & AndRHS iff A&AndRHS==0 and AndRHS
1339  // has 1's for all bits that the subtraction with A might affect.
1340  if (Op0I->hasOneUse() && !match(Op0LHS, m_Zero())) {
1341  uint32_t BitWidth = AndRHSMask.getBitWidth();
1342  uint32_t Zeros = AndRHSMask.countLeadingZeros();
1343  APInt Mask = APInt::getLowBitsSet(BitWidth, BitWidth - Zeros);
1344 
1345  if (MaskedValueIsZero(Op0LHS, Mask, 0, &I)) {
1346  Value *NewNeg = Builder->CreateNeg(Op0RHS);
1347  return BinaryOperator::CreateAnd(NewNeg, AndRHS);
1348  }
1349  }
1350  break;
1351 
1352  case Instruction::Shl:
1353  case Instruction::LShr:
1354  // (1 << x) & 1 --> zext(x == 0)
1355  // (1 >> x) & 1 --> zext(x == 0)
1356  if (AndRHSMask == 1 && Op0LHS == AndRHS) {
1357  Value *NewICmp =
1358  Builder->CreateICmpEQ(Op0RHS, Constant::getNullValue(I.getType()));
1359  return new ZExtInst(NewICmp, I.getType());
1360  }
1361  break;
1362  }
1363 
1364  if (ConstantInt *Op0CI = dyn_cast<ConstantInt>(Op0I->getOperand(1)))
1365  if (Instruction *Res = OptAndOp(Op0I, Op0CI, AndRHS, I))
1366  return Res;
1367  }
1368 
1369  // If this is an integer truncation, and if the source is an 'and' with
1370  // immediate, transform it. This frequently occurs for bitfield accesses.
1371  {
1372  Value *X = nullptr; ConstantInt *YC = nullptr;
1373  if (match(Op0, m_Trunc(m_And(m_Value(X), m_ConstantInt(YC))))) {
1374  // Change: and (trunc (and X, YC) to T), C2
1375  // into : and (trunc X to T), trunc(YC) & C2
1376  // This will fold the two constants together, which may allow
1377  // other simplifications.
1378  Value *NewCast = Builder->CreateTrunc(X, I.getType(), "and.shrunk");
1379  Constant *C3 = ConstantExpr::getTrunc(YC, I.getType());
1380  C3 = ConstantExpr::getAnd(C3, AndRHS);
1381  return BinaryOperator::CreateAnd(NewCast, C3);
1382  }
1383  }
1384 
1385  if (Instruction *FoldedLogic = foldOpWithConstantIntoOperand(I))
1386  return FoldedLogic;
1387  }
1388 
1389  if (Instruction *DeMorgan = matchDeMorgansLaws(I, Builder))
1390  return DeMorgan;
1391 
1392  {
1393  Value *A = nullptr, *B = nullptr, *C = nullptr, *D = nullptr;
1394  // (A|B) & ~(A&B) -> A^B
1395  if (match(Op0, m_Or(m_Value(A), m_Value(B))) &&
1396  match(Op1, m_Not(m_And(m_Value(C), m_Value(D)))) &&
1397  ((A == C && B == D) || (A == D && B == C)))
1398  return BinaryOperator::CreateXor(A, B);
1399 
1400  // ~(A&B) & (A|B) -> A^B
1401  if (match(Op1, m_Or(m_Value(A), m_Value(B))) &&
1402  match(Op0, m_Not(m_And(m_Value(C), m_Value(D)))) &&
1403  ((A == C && B == D) || (A == D && B == C)))
1404  return BinaryOperator::CreateXor(A, B);
1405 
1406  // A&(A^B) => A & ~B
1407  {
1408  Value *tmpOp0 = Op0;
1409  Value *tmpOp1 = Op1;
1410  if (match(Op0, m_OneUse(m_Xor(m_Value(A), m_Value(B))))) {
1411  if (A == Op1 || B == Op1 ) {
1412  tmpOp1 = Op0;
1413  tmpOp0 = Op1;
1414  // Simplify below
1415  }
1416  }
1417 
1418  if (match(tmpOp1, m_OneUse(m_Xor(m_Value(A), m_Value(B))))) {
1419  if (B == tmpOp0) {
1420  std::swap(A, B);
1421  }
1422  // Notice that the pattern (A&(~B)) is actually (A&(-1^B)), so if
1423  // A is originally -1 (or a vector of -1 and undefs), then we enter
1424  // an endless loop. By checking that A is non-constant we ensure that
1425  // we will never get to the loop.
1426  if (A == tmpOp0 && !isa<Constant>(A)) // A&(A^B) -> A & ~B
1427  return BinaryOperator::CreateAnd(A, Builder->CreateNot(B));
1428  }
1429  }
1430 
1431  // (A&((~A)|B)) -> A&B
1432  if (match(Op0, m_Or(m_Not(m_Specific(Op1)), m_Value(A))) ||
1433  match(Op0, m_Or(m_Value(A), m_Not(m_Specific(Op1)))))
1434  return BinaryOperator::CreateAnd(A, Op1);
1435  if (match(Op1, m_Or(m_Not(m_Specific(Op0)), m_Value(A))) ||
1436  match(Op1, m_Or(m_Value(A), m_Not(m_Specific(Op0)))))
1437  return BinaryOperator::CreateAnd(A, Op0);
1438 
1439  // (A ^ B) & ((B ^ C) ^ A) -> (A ^ B) & ~C
1440  if (match(Op0, m_Xor(m_Value(A), m_Value(B))))
1441  if (match(Op1, m_Xor(m_Xor(m_Specific(B), m_Value(C)), m_Specific(A))))
1442  if (Op1->hasOneUse() || cast<BinaryOperator>(Op1)->hasOneUse())
1443  return BinaryOperator::CreateAnd(Op0, Builder->CreateNot(C));
1444 
1445  // ((A ^ C) ^ B) & (B ^ A) -> (B ^ A) & ~C
1446  if (match(Op0, m_Xor(m_Xor(m_Value(A), m_Value(C)), m_Value(B))))
1447  if (match(Op1, m_Xor(m_Specific(B), m_Specific(A))))
1448  if (Op0->hasOneUse() || cast<BinaryOperator>(Op0)->hasOneUse())
1449  return BinaryOperator::CreateAnd(Op1, Builder->CreateNot(C));
1450 
1451  // (A | B) & ((~A) ^ B) -> (A & B)
1452  if (match(Op0, m_Or(m_Value(A), m_Value(B))) &&
1453  match(Op1, m_Xor(m_Not(m_Specific(A)), m_Specific(B))))
1454  return BinaryOperator::CreateAnd(A, B);
1455 
1456  // ((~A) ^ B) & (A | B) -> (A & B)
1457  // ((~A) ^ B) & (B | A) -> (A & B)
1458  if (match(Op0, m_Xor(m_Not(m_Value(A)), m_Value(B))) &&
1459  match(Op1, m_c_Or(m_Specific(A), m_Specific(B))))
1460  return BinaryOperator::CreateAnd(A, B);
1461  }
1462 
1463  {
1464  ICmpInst *LHS = dyn_cast<ICmpInst>(Op0);
1465  ICmpInst *RHS = dyn_cast<ICmpInst>(Op1);
1466  if (LHS && RHS)
1467  if (Value *Res = FoldAndOfICmps(LHS, RHS))
1468  return replaceInstUsesWith(I, Res);
1469 
1470  // TODO: Make this recursive; it's a little tricky because an arbitrary
1471  // number of 'and' instructions might have to be created.
1472  Value *X, *Y;
1473  if (LHS && match(Op1, m_OneUse(m_And(m_Value(X), m_Value(Y))))) {
1474  if (auto *Cmp = dyn_cast<ICmpInst>(X))
1475  if (Value *Res = FoldAndOfICmps(LHS, Cmp))
1476  return replaceInstUsesWith(I, Builder->CreateAnd(Res, Y));
1477  if (auto *Cmp = dyn_cast<ICmpInst>(Y))
1478  if (Value *Res = FoldAndOfICmps(LHS, Cmp))
1479  return replaceInstUsesWith(I, Builder->CreateAnd(Res, X));
1480  }
1481  if (RHS && match(Op0, m_OneUse(m_And(m_Value(X), m_Value(Y))))) {
1482  if (auto *Cmp = dyn_cast<ICmpInst>(X))
1483  if (Value *Res = FoldAndOfICmps(Cmp, RHS))
1484  return replaceInstUsesWith(I, Builder->CreateAnd(Res, Y));
1485  if (auto *Cmp = dyn_cast<ICmpInst>(Y))
1486  if (Value *Res = FoldAndOfICmps(Cmp, RHS))
1487  return replaceInstUsesWith(I, Builder->CreateAnd(Res, X));
1488  }
1489  }
1490 
1491  // If and'ing two fcmp, try combine them into one.
1492  if (FCmpInst *LHS = dyn_cast<FCmpInst>(I.getOperand(0)))
1493  if (FCmpInst *RHS = dyn_cast<FCmpInst>(I.getOperand(1)))
1494  if (Value *Res = FoldAndOfFCmps(LHS, RHS))
1495  return replaceInstUsesWith(I, Res);
1496 
1497  if (Instruction *CastedAnd = foldCastedBitwiseLogic(I))
1498  return CastedAnd;
1499 
1501  return Select;
1502 
1503  return Changed ? &I : nullptr;
1504 }
1505 
1506 /// Given an OR instruction, check to see if this is a bswap idiom. If so,
1507 /// insert the new intrinsic and return it.
1508 Instruction *InstCombiner::MatchBSwap(BinaryOperator &I) {
1509  Value *Op0 = I.getOperand(0), *Op1 = I.getOperand(1);
1510 
1511  // Look through zero extends.
1512  if (Instruction *Ext = dyn_cast<ZExtInst>(Op0))
1513  Op0 = Ext->getOperand(0);
1514 
1515  if (Instruction *Ext = dyn_cast<ZExtInst>(Op1))
1516  Op1 = Ext->getOperand(0);
1517 
1518  // (A | B) | C and A | (B | C) -> bswap if possible.
1519  bool OrOfOrs = match(Op0, m_Or(m_Value(), m_Value())) ||
1520  match(Op1, m_Or(m_Value(), m_Value()));
1521 
1522  // (A >> B) | (C << D) and (A << B) | (B >> C) -> bswap if possible.
1523  bool OrOfShifts = match(Op0, m_LogicalShift(m_Value(), m_Value())) &&
1524  match(Op1, m_LogicalShift(m_Value(), m_Value()));
1525 
1526  // (A & B) | (C & D) -> bswap if possible.
1527  bool OrOfAnds = match(Op0, m_And(m_Value(), m_Value())) &&
1528  match(Op1, m_And(m_Value(), m_Value()));
1529 
1530  if (!OrOfOrs && !OrOfShifts && !OrOfAnds)
1531  return nullptr;
1532 
1534  if (!recognizeBSwapOrBitReverseIdiom(&I, true, false, Insts))
1535  return nullptr;
1536  Instruction *LastInst = Insts.pop_back_val();
1537  LastInst->removeFromParent();
1538 
1539  for (auto *Inst : Insts)
1540  Worklist.Add(Inst);
1541  return LastInst;
1542 }
1543 
1544 /// If all elements of two constant vectors are 0/-1 and inverses, return true.
1546  unsigned NumElts = C1->getType()->getVectorNumElements();
1547  for (unsigned i = 0; i != NumElts; ++i) {
1548  Constant *EltC1 = C1->getAggregateElement(i);
1549  Constant *EltC2 = C2->getAggregateElement(i);
1550  if (!EltC1 || !EltC2)
1551  return false;
1552 
1553  // One element must be all ones, and the other must be all zeros.
1554  // FIXME: Allow undef elements.
1555  if (!((match(EltC1, m_Zero()) && match(EltC2, m_AllOnes())) ||
1556  (match(EltC2, m_Zero()) && match(EltC1, m_AllOnes()))))
1557  return false;
1558  }
1559  return true;
1560 }
1561 
1562 /// We have an expression of the form (A & C) | (B & D). If A is a scalar or
1563 /// vector composed of all-zeros or all-ones values and is the bitwise 'not' of
1564 /// B, it can be used as the condition operand of a select instruction.
1566  InstCombiner::BuilderTy &Builder) {
1567  // If these are scalars or vectors of i1, A can be used directly.
1568  Type *Ty = A->getType();
1569  if (match(A, m_Not(m_Specific(B))) && Ty->getScalarType()->isIntegerTy(1))
1570  return A;
1571 
1572  // If A and B are sign-extended, look through the sexts to find the booleans.
1573  Value *Cond;
1574  if (match(A, m_SExt(m_Value(Cond))) &&
1575  Cond->getType()->getScalarType()->isIntegerTy(1) &&
1577  m_SExt(m_Not(m_Specific(Cond))))))
1578  return Cond;
1579 
1580  // All scalar (and most vector) possibilities should be handled now.
1581  // Try more matches that only apply to non-splat constant vectors.
1582  if (!Ty->isVectorTy())
1583  return nullptr;
1584 
1585  // If both operands are constants, see if the constants are inverse bitmasks.
1586  Constant *AC, *BC;
1587  if (match(A, m_Constant(AC)) && match(B, m_Constant(BC)) &&
1588  areInverseVectorBitmasks(AC, BC))
1590 
1591  // If both operands are xor'd with constants using the same sexted boolean
1592  // operand, see if the constants are inverse bitmasks.
1593  if (match(A, (m_Xor(m_SExt(m_Value(Cond)), m_Constant(AC)))) &&
1594  match(B, (m_Xor(m_SExt(m_Specific(Cond)), m_Constant(BC)))) &&
1595  Cond->getType()->getScalarType()->isIntegerTy(1) &&
1596  areInverseVectorBitmasks(AC, BC)) {
1598  return Builder.CreateXor(Cond, AC);
1599  }
1600  return nullptr;
1601 }
1602 
1603 /// We have an expression of the form (A & C) | (B & D). Try to simplify this
1604 /// to "A' ? C : D", where A' is a boolean or vector of booleans.
1606  InstCombiner::BuilderTy &Builder) {
1607  // The potential condition of the select may be bitcasted. In that case, look
1608  // through its bitcast and the corresponding bitcast of the 'not' condition.
1609  Type *OrigType = A->getType();
1610  Value *SrcA, *SrcB;
1611  if (match(A, m_OneUse(m_BitCast(m_Value(SrcA)))) &&
1612  match(B, m_OneUse(m_BitCast(m_Value(SrcB))))) {
1613  A = SrcA;
1614  B = SrcB;
1615  }
1616 
1617  if (Value *Cond = getSelectCondition(A, B, Builder)) {
1618  // ((bc Cond) & C) | ((bc ~Cond) & D) --> bc (select Cond, (bc C), (bc D))
1619  // The bitcasts will either all exist or all not exist. The builder will
1620  // not create unnecessary casts if the types already match.
1621  Value *BitcastC = Builder.CreateBitCast(C, A->getType());
1622  Value *BitcastD = Builder.CreateBitCast(D, A->getType());
1623  Value *Select = Builder.CreateSelect(Cond, BitcastC, BitcastD);
1624  return Builder.CreateBitCast(Select, OrigType);
1625  }
1626 
1627  return nullptr;
1628 }
1629 
1630 /// Fold (icmp)|(icmp) if possible.
1632  Instruction *CxtI) {
1633  ICmpInst::Predicate LHSCC = LHS->getPredicate(), RHSCC = RHS->getPredicate();
1634 
1635  // Fold (iszero(A & K1) | iszero(A & K2)) -> (A & (K1 | K2)) != (K1 | K2)
1636  // if K1 and K2 are a one-bit mask.
1637  ConstantInt *LHSCst = dyn_cast<ConstantInt>(LHS->getOperand(1));
1638  ConstantInt *RHSCst = dyn_cast<ConstantInt>(RHS->getOperand(1));
1639 
1640  if (LHS->getPredicate() == ICmpInst::ICMP_EQ && LHSCst && LHSCst->isZero() &&
1641  RHS->getPredicate() == ICmpInst::ICMP_EQ && RHSCst && RHSCst->isZero()) {
1642 
1645  if (LAnd && RAnd && LAnd->hasOneUse() && RHS->hasOneUse() &&
1646  LAnd->getOpcode() == Instruction::And &&
1647  RAnd->getOpcode() == Instruction::And) {
1648 
1649  Value *Mask = nullptr;
1650  Value *Masked = nullptr;
1651  if (LAnd->getOperand(0) == RAnd->getOperand(0) &&
1652  isKnownToBeAPowerOfTwo(LAnd->getOperand(1), DL, false, 0, &AC, CxtI,
1653  &DT) &&
1654  isKnownToBeAPowerOfTwo(RAnd->getOperand(1), DL, false, 0, &AC, CxtI,
1655  &DT)) {
1656  Mask = Builder->CreateOr(LAnd->getOperand(1), RAnd->getOperand(1));
1657  Masked = Builder->CreateAnd(LAnd->getOperand(0), Mask);
1658  } else if (LAnd->getOperand(1) == RAnd->getOperand(1) &&
1659  isKnownToBeAPowerOfTwo(LAnd->getOperand(0), DL, false, 0, &AC,
1660  CxtI, &DT) &&
1661  isKnownToBeAPowerOfTwo(RAnd->getOperand(0), DL, false, 0, &AC,
1662  CxtI, &DT)) {
1663  Mask = Builder->CreateOr(LAnd->getOperand(0), RAnd->getOperand(0));
1664  Masked = Builder->CreateAnd(LAnd->getOperand(1), Mask);
1665  }
1666 
1667  if (Masked)
1668  return Builder->CreateICmp(ICmpInst::ICMP_NE, Masked, Mask);
1669  }
1670  }
1671 
1672  // Fold (icmp ult/ule (A + C1), C3) | (icmp ult/ule (A + C2), C3)
1673  // --> (icmp ult/ule ((A & ~(C1 ^ C2)) + max(C1, C2)), C3)
1674  // The original condition actually refers to the following two ranges:
1675  // [MAX_UINT-C1+1, MAX_UINT-C1+1+C3] and [MAX_UINT-C2+1, MAX_UINT-C2+1+C3]
1676  // We can fold these two ranges if:
1677  // 1) C1 and C2 is unsigned greater than C3.
1678  // 2) The two ranges are separated.
1679  // 3) C1 ^ C2 is one-bit mask.
1680  // 4) LowRange1 ^ LowRange2 and HighRange1 ^ HighRange2 are one-bit mask.
1681  // This implies all values in the two ranges differ by exactly one bit.
1682 
1683  if ((LHSCC == ICmpInst::ICMP_ULT || LHSCC == ICmpInst::ICMP_ULE) &&
1684  LHSCC == RHSCC && LHSCst && RHSCst && LHS->hasOneUse() &&
1685  RHS->hasOneUse() && LHSCst->getType() == RHSCst->getType() &&
1686  LHSCst->getValue() == (RHSCst->getValue())) {
1687 
1688  Value *LAdd = LHS->getOperand(0);
1689  Value *RAdd = RHS->getOperand(0);
1690 
1691  Value *LAddOpnd, *RAddOpnd;
1692  ConstantInt *LAddCst, *RAddCst;
1693  if (match(LAdd, m_Add(m_Value(LAddOpnd), m_ConstantInt(LAddCst))) &&
1694  match(RAdd, m_Add(m_Value(RAddOpnd), m_ConstantInt(RAddCst))) &&
1695  LAddCst->getValue().ugt(LHSCst->getValue()) &&
1696  RAddCst->getValue().ugt(LHSCst->getValue())) {
1697 
1698  APInt DiffCst = LAddCst->getValue() ^ RAddCst->getValue();
1699  if (LAddOpnd == RAddOpnd && DiffCst.isPowerOf2()) {
1700  ConstantInt *MaxAddCst = nullptr;
1701  if (LAddCst->getValue().ult(RAddCst->getValue()))
1702  MaxAddCst = RAddCst;
1703  else
1704  MaxAddCst = LAddCst;
1705 
1706  APInt RRangeLow = -RAddCst->getValue();
1707  APInt RRangeHigh = RRangeLow + LHSCst->getValue();
1708  APInt LRangeLow = -LAddCst->getValue();
1709  APInt LRangeHigh = LRangeLow + LHSCst->getValue();
1710  APInt LowRangeDiff = RRangeLow ^ LRangeLow;
1711  APInt HighRangeDiff = RRangeHigh ^ LRangeHigh;
1712  APInt RangeDiff = LRangeLow.sgt(RRangeLow) ? LRangeLow - RRangeLow
1713  : RRangeLow - LRangeLow;
1714 
1715  if (LowRangeDiff.isPowerOf2() && LowRangeDiff == HighRangeDiff &&
1716  RangeDiff.ugt(LHSCst->getValue())) {
1717  Value *MaskCst = ConstantInt::get(LAddCst->getType(), ~DiffCst);
1718 
1719  Value *NewAnd = Builder->CreateAnd(LAddOpnd, MaskCst);
1720  Value *NewAdd = Builder->CreateAdd(NewAnd, MaxAddCst);
1721  return (Builder->CreateICmp(LHS->getPredicate(), NewAdd, LHSCst));
1722  }
1723  }
1724  }
1725  }
1726 
1727  // (icmp1 A, B) | (icmp2 A, B) --> (icmp3 A, B)
1728  if (PredicatesFoldable(LHSCC, RHSCC)) {
1729  if (LHS->getOperand(0) == RHS->getOperand(1) &&
1730  LHS->getOperand(1) == RHS->getOperand(0))
1731  LHS->swapOperands();
1732  if (LHS->getOperand(0) == RHS->getOperand(0) &&
1733  LHS->getOperand(1) == RHS->getOperand(1)) {
1734  Value *Op0 = LHS->getOperand(0), *Op1 = LHS->getOperand(1);
1735  unsigned Code = getICmpCode(LHS) | getICmpCode(RHS);
1736  bool isSigned = LHS->isSigned() || RHS->isSigned();
1737  return getNewICmpValue(isSigned, Code, Op0, Op1, Builder);
1738  }
1739  }
1740 
1741  // handle (roughly):
1742  // (icmp ne (A & B), C) | (icmp ne (A & D), E)
1743  if (Value *V = foldLogOpOfMaskedICmps(LHS, RHS, false, Builder))
1744  return V;
1745 
1746  Value *Val = LHS->getOperand(0), *Val2 = RHS->getOperand(0);
1747  if (LHS->hasOneUse() || RHS->hasOneUse()) {
1748  // (icmp eq B, 0) | (icmp ult A, B) -> (icmp ule A, B-1)
1749  // (icmp eq B, 0) | (icmp ugt B, A) -> (icmp ule A, B-1)
1750  Value *A = nullptr, *B = nullptr;
1751  if (LHSCC == ICmpInst::ICMP_EQ && LHSCst && LHSCst->isZero()) {
1752  B = Val;
1753  if (RHSCC == ICmpInst::ICMP_ULT && Val == RHS->getOperand(1))
1754  A = Val2;
1755  else if (RHSCC == ICmpInst::ICMP_UGT && Val == Val2)
1756  A = RHS->getOperand(1);
1757  }
1758  // (icmp ult A, B) | (icmp eq B, 0) -> (icmp ule A, B-1)
1759  // (icmp ugt B, A) | (icmp eq B, 0) -> (icmp ule A, B-1)
1760  else if (RHSCC == ICmpInst::ICMP_EQ && RHSCst && RHSCst->isZero()) {
1761  B = Val2;
1762  if (LHSCC == ICmpInst::ICMP_ULT && Val2 == LHS->getOperand(1))
1763  A = Val;
1764  else if (LHSCC == ICmpInst::ICMP_UGT && Val2 == Val)
1765  A = LHS->getOperand(1);
1766  }
1767  if (A && B)
1768  return Builder->CreateICmp(
1770  Builder->CreateAdd(B, ConstantInt::getSigned(B->getType(), -1)), A);
1771  }
1772 
1773  // E.g. (icmp slt x, 0) | (icmp sgt x, n) --> icmp ugt x, n
1774  if (Value *V = simplifyRangeCheck(LHS, RHS, /*Inverted=*/true))
1775  return V;
1776 
1777  // E.g. (icmp sgt x, n) | (icmp slt x, 0) --> icmp ugt x, n
1778  if (Value *V = simplifyRangeCheck(RHS, LHS, /*Inverted=*/true))
1779  return V;
1780 
1781  // This only handles icmp of constants: (icmp1 A, C1) | (icmp2 B, C2).
1782  if (!LHSCst || !RHSCst) return nullptr;
1783 
1784  if (LHSCst == RHSCst && LHSCC == RHSCC) {
1785  // (icmp ne A, 0) | (icmp ne B, 0) --> (icmp ne (A|B), 0)
1786  if (LHSCC == ICmpInst::ICMP_NE && LHSCst->isZero()) {
1787  Value *NewOr = Builder->CreateOr(Val, Val2);
1788  return Builder->CreateICmp(LHSCC, NewOr, LHSCst);
1789  }
1790  }
1791 
1792  // (icmp ult (X + CA), C1) | (icmp eq X, C2) -> (icmp ule (X + CA), C1)
1793  // iff C2 + CA == C1.
1794  if (LHSCC == ICmpInst::ICMP_ULT && RHSCC == ICmpInst::ICMP_EQ) {
1795  ConstantInt *AddCst;
1796  if (match(Val, m_Add(m_Specific(Val2), m_ConstantInt(AddCst))))
1797  if (RHSCst->getValue() + AddCst->getValue() == LHSCst->getValue())
1798  return Builder->CreateICmpULE(Val, LHSCst);
1799  }
1800 
1801  // From here on, we only handle:
1802  // (icmp1 A, C1) | (icmp2 A, C2) --> something simpler.
1803  if (Val != Val2) return nullptr;
1804 
1805  // ICMP_[US][GL]E X, CST is folded to ICMP_[US][GL]T elsewhere.
1806  if (LHSCC == ICmpInst::ICMP_UGE || LHSCC == ICmpInst::ICMP_ULE ||
1807  RHSCC == ICmpInst::ICMP_UGE || RHSCC == ICmpInst::ICMP_ULE ||
1808  LHSCC == ICmpInst::ICMP_SGE || LHSCC == ICmpInst::ICMP_SLE ||
1809  RHSCC == ICmpInst::ICMP_SGE || RHSCC == ICmpInst::ICMP_SLE)
1810  return nullptr;
1811 
1812  // We can't fold (ugt x, C) | (sgt x, C2).
1813  if (!PredicatesFoldable(LHSCC, RHSCC))
1814  return nullptr;
1815 
1816  // Ensure that the larger constant is on the RHS.
1817  bool ShouldSwap;
1818  if (CmpInst::isSigned(LHSCC) ||
1819  (ICmpInst::isEquality(LHSCC) &&
1820  CmpInst::isSigned(RHSCC)))
1821  ShouldSwap = LHSCst->getValue().sgt(RHSCst->getValue());
1822  else
1823  ShouldSwap = LHSCst->getValue().ugt(RHSCst->getValue());
1824 
1825  if (ShouldSwap) {
1826  std::swap(LHS, RHS);
1827  std::swap(LHSCst, RHSCst);
1828  std::swap(LHSCC, RHSCC);
1829  }
1830 
1831  // At this point, we know we have two icmp instructions
1832  // comparing a value against two constants and or'ing the result
1833  // together. Because of the above check, we know that we only have
1834  // ICMP_EQ, ICMP_NE, ICMP_LT, and ICMP_GT here. We also know (from the
1835  // icmp folding check above), that the two constants are not
1836  // equal.
1837  assert(LHSCst != RHSCst && "Compares not folded above?");
1838 
1839  switch (LHSCC) {
1840  default: llvm_unreachable("Unknown integer condition code!");
1841  case ICmpInst::ICMP_EQ:
1842  switch (RHSCC) {
1843  default: llvm_unreachable("Unknown integer condition code!");
1844  case ICmpInst::ICMP_EQ:
1845  if (LHS->getOperand(0) == RHS->getOperand(0)) {
1846  // if LHSCst and RHSCst differ only by one bit:
1847  // (A == C1 || A == C2) -> (A | (C1 ^ C2)) == C2
1848  assert(LHSCst->getValue().ule(LHSCst->getValue()));
1849 
1850  APInt Xor = LHSCst->getValue() ^ RHSCst->getValue();
1851  if (Xor.isPowerOf2()) {
1852  Value *Cst = Builder->getInt(Xor);
1853  Value *Or = Builder->CreateOr(LHS->getOperand(0), Cst);
1854  return Builder->CreateICmp(ICmpInst::ICMP_EQ, Or, RHSCst);
1855  }
1856  }
1857 
1858  if (LHSCst == SubOne(RHSCst)) {
1859  // (X == 13 | X == 14) -> X-13 <u 2
1860  Constant *AddCST = ConstantExpr::getNeg(LHSCst);
1861  Value *Add = Builder->CreateAdd(Val, AddCST, Val->getName()+".off");
1862  AddCST = ConstantExpr::getSub(AddOne(RHSCst), LHSCst);
1863  return Builder->CreateICmpULT(Add, AddCST);
1864  }
1865 
1866  break; // (X == 13 | X == 15) -> no change
1867  case ICmpInst::ICMP_UGT: // (X == 13 | X u> 14) -> no change
1868  case ICmpInst::ICMP_SGT: // (X == 13 | X s> 14) -> no change
1869  break;
1870  case ICmpInst::ICMP_NE: // (X == 13 | X != 15) -> X != 15
1871  case ICmpInst::ICMP_ULT: // (X == 13 | X u< 15) -> X u< 15
1872  case ICmpInst::ICMP_SLT: // (X == 13 | X s< 15) -> X s< 15
1873  return RHS;
1874  }
1875  break;
1876  case ICmpInst::ICMP_NE:
1877  switch (RHSCC) {
1878  default: llvm_unreachable("Unknown integer condition code!");
1879  case ICmpInst::ICMP_EQ: // (X != 13 | X == 15) -> X != 13
1880  case ICmpInst::ICMP_UGT: // (X != 13 | X u> 15) -> X != 13
1881  case ICmpInst::ICMP_SGT: // (X != 13 | X s> 15) -> X != 13
1882  return LHS;
1883  case ICmpInst::ICMP_NE: // (X != 13 | X != 15) -> true
1884  case ICmpInst::ICMP_ULT: // (X != 13 | X u< 15) -> true
1885  case ICmpInst::ICMP_SLT: // (X != 13 | X s< 15) -> true
1886  return Builder->getTrue();
1887  }
1888  case ICmpInst::ICMP_ULT:
1889  switch (RHSCC) {
1890  default: llvm_unreachable("Unknown integer condition code!");
1891  case ICmpInst::ICMP_EQ: // (X u< 13 | X == 14) -> no change
1892  break;
1893  case ICmpInst::ICMP_UGT: // (X u< 13 | X u> 15) -> (X-13) u> 2
1894  // If RHSCst is [us]MAXINT, it is always false. Not handling
1895  // this can cause overflow.
1896  if (RHSCst->isMaxValue(false))
1897  return LHS;
1898  return insertRangeTest(Val, LHSCst->getValue(), RHSCst->getValue() + 1,
1899  false, false);
1900  case ICmpInst::ICMP_SGT: // (X u< 13 | X s> 15) -> no change
1901  break;
1902  case ICmpInst::ICMP_NE: // (X u< 13 | X != 15) -> X != 15
1903  case ICmpInst::ICMP_ULT: // (X u< 13 | X u< 15) -> X u< 15
1904  return RHS;
1905  case ICmpInst::ICMP_SLT: // (X u< 13 | X s< 15) -> no change
1906  break;
1907  }
1908  break;
1909  case ICmpInst::ICMP_SLT:
1910  switch (RHSCC) {
1911  default: llvm_unreachable("Unknown integer condition code!");
1912  case ICmpInst::ICMP_EQ: // (X s< 13 | X == 14) -> no change
1913  break;
1914  case ICmpInst::ICMP_SGT: // (X s< 13 | X s> 15) -> (X-13) s> 2
1915  // If RHSCst is [us]MAXINT, it is always false. Not handling
1916  // this can cause overflow.
1917  if (RHSCst->isMaxValue(true))
1918  return LHS;
1919  return insertRangeTest(Val, LHSCst->getValue(), RHSCst->getValue() + 1,
1920  true, false);
1921  case ICmpInst::ICMP_UGT: // (X s< 13 | X u> 15) -> no change
1922  break;
1923  case ICmpInst::ICMP_NE: // (X s< 13 | X != 15) -> X != 15
1924  case ICmpInst::ICMP_SLT: // (X s< 13 | X s< 15) -> X s< 15
1925  return RHS;
1926  case ICmpInst::ICMP_ULT: // (X s< 13 | X u< 15) -> no change
1927  break;
1928  }
1929  break;
1930  case ICmpInst::ICMP_UGT:
1931  switch (RHSCC) {
1932  default: llvm_unreachable("Unknown integer condition code!");
1933  case ICmpInst::ICMP_EQ: // (X u> 13 | X == 15) -> X u> 13
1934  case ICmpInst::ICMP_UGT: // (X u> 13 | X u> 15) -> X u> 13
1935  return LHS;
1936  case ICmpInst::ICMP_SGT: // (X u> 13 | X s> 15) -> no change
1937  break;
1938  case ICmpInst::ICMP_NE: // (X u> 13 | X != 15) -> true
1939  case ICmpInst::ICMP_ULT: // (X u> 13 | X u< 15) -> true
1940  return Builder->getTrue();
1941  case ICmpInst::ICMP_SLT: // (X u> 13 | X s< 15) -> no change
1942  break;
1943  }
1944  break;
1945  case ICmpInst::ICMP_SGT:
1946  switch (RHSCC) {
1947  default: llvm_unreachable("Unknown integer condition code!");
1948  case ICmpInst::ICMP_EQ: // (X s> 13 | X == 15) -> X > 13
1949  case ICmpInst::ICMP_SGT: // (X s> 13 | X s> 15) -> X > 13
1950  return LHS;
1951  case ICmpInst::ICMP_UGT: // (X s> 13 | X u> 15) -> no change
1952  break;
1953  case ICmpInst::ICMP_NE: // (X s> 13 | X != 15) -> true
1954  case ICmpInst::ICMP_SLT: // (X s> 13 | X s< 15) -> true
1955  return Builder->getTrue();
1956  case ICmpInst::ICMP_ULT: // (X s> 13 | X u< 15) -> no change
1957  break;
1958  }
1959  break;
1960  }
1961  return nullptr;
1962 }
1963 
1964 /// Optimize (fcmp)|(fcmp). NOTE: Unlike the rest of instcombine, this returns
1965 /// a Value which should already be inserted into the function.
1967  Value *Op0LHS = LHS->getOperand(0), *Op0RHS = LHS->getOperand(1);
1968  Value *Op1LHS = RHS->getOperand(0), *Op1RHS = RHS->getOperand(1);
1969  FCmpInst::Predicate Op0CC = LHS->getPredicate(), Op1CC = RHS->getPredicate();
1970 
1971  if (Op0LHS == Op1RHS && Op0RHS == Op1LHS) {
1972  // Swap RHS operands to match LHS.
1973  Op1CC = FCmpInst::getSwappedPredicate(Op1CC);
1974  std::swap(Op1LHS, Op1RHS);
1975  }
1976 
1977  // Simplify (fcmp cc0 x, y) | (fcmp cc1 x, y).
1978  // This is a similar transformation to the one in FoldAndOfFCmps.
1979  //
1980  // Since (R & CC0) and (R & CC1) are either R or 0, we actually have this:
1981  // bool(R & CC0) || bool(R & CC1)
1982  // = bool((R & CC0) | (R & CC1))
1983  // = bool(R & (CC0 | CC1)) <= by reversed distribution (contribution? ;)
1984  if (Op0LHS == Op1LHS && Op0RHS == Op1RHS)
1985  return getFCmpValue(getFCmpCode(Op0CC) | getFCmpCode(Op1CC), Op0LHS, Op0RHS,
1986  Builder);
1987 
1988  if (LHS->getPredicate() == FCmpInst::FCMP_UNO &&
1989  RHS->getPredicate() == FCmpInst::FCMP_UNO &&
1990  LHS->getOperand(0)->getType() == RHS->getOperand(0)->getType()) {
1991  if (ConstantFP *LHSC = dyn_cast<ConstantFP>(LHS->getOperand(1)))
1992  if (ConstantFP *RHSC = dyn_cast<ConstantFP>(RHS->getOperand(1))) {
1993  // If either of the constants are nans, then the whole thing returns
1994  // true.
1995  if (LHSC->getValueAPF().isNaN() || RHSC->getValueAPF().isNaN())
1996  return Builder->getTrue();
1997 
1998  // Otherwise, no need to compare the two constants, compare the
1999  // rest.
2000  return Builder->CreateFCmpUNO(LHS->getOperand(0), RHS->getOperand(0));
2001  }
2002 
2003  // Handle vector zeros. This occurs because the canonical form of
2004  // "fcmp uno x,x" is "fcmp uno x, 0".
2005  if (isa<ConstantAggregateZero>(LHS->getOperand(1)) &&
2006  isa<ConstantAggregateZero>(RHS->getOperand(1)))
2007  return Builder->CreateFCmpUNO(LHS->getOperand(0), RHS->getOperand(0));
2008 
2009  return nullptr;
2010  }
2011 
2012  return nullptr;
2013 }
2014 
2015 /// This helper function folds:
2016 ///
2017 /// ((A | B) & C1) | (B & C2)
2018 ///
2019 /// into:
2020 ///
2021 /// (A & C1) | B
2022 ///
2023 /// when the XOR of the two constants is "all ones" (-1).
2025  Value *A, Value *B, Value *C) {
2026  ConstantInt *CI1 = dyn_cast<ConstantInt>(C);
2027  if (!CI1) return nullptr;
2028 
2029  Value *V1 = nullptr;
2030  ConstantInt *CI2 = nullptr;
2031  if (!match(Op, m_And(m_Value(V1), m_ConstantInt(CI2)))) return nullptr;
2032 
2033  APInt Xor = CI1->getValue() ^ CI2->getValue();
2034  if (!Xor.isAllOnesValue()) return nullptr;
2035 
2036  if (V1 == A || V1 == B) {
2037  Value *NewOp = Builder->CreateAnd((V1 == A) ? B : A, CI1);
2038  return BinaryOperator::CreateOr(NewOp, V1);
2039  }
2040 
2041  return nullptr;
2042 }
2043 
2044 /// \brief This helper function folds:
2045 ///
2046 /// ((A | B) & C1) ^ (B & C2)
2047 ///
2048 /// into:
2049 ///
2050 /// (A & C1) ^ B
2051 ///
2052 /// when the XOR of the two constants is "all ones" (-1).
2054  Value *A, Value *B, Value *C) {
2055  ConstantInt *CI1 = dyn_cast<ConstantInt>(C);
2056  if (!CI1)
2057  return nullptr;
2058 
2059  Value *V1 = nullptr;
2060  ConstantInt *CI2 = nullptr;
2061  if (!match(Op, m_And(m_Value(V1), m_ConstantInt(CI2))))
2062  return nullptr;
2063 
2064  APInt Xor = CI1->getValue() ^ CI2->getValue();
2065  if (!Xor.isAllOnesValue())
2066  return nullptr;
2067 
2068  if (V1 == A || V1 == B) {
2069  Value *NewOp = Builder->CreateAnd(V1 == A ? B : A, CI1);
2070  return BinaryOperator::CreateXor(NewOp, V1);
2071  }
2072 
2073  return nullptr;
2074 }
2075 
2076 // FIXME: We use commutative matchers (m_c_*) for some, but not all, matches
2077 // here. We should standardize that construct where it is needed or choose some
2078 // other way to ensure that commutated variants of patterns are not missed.
2080  bool Changed = SimplifyAssociativeOrCommutative(I);
2081  Value *Op0 = I.getOperand(0), *Op1 = I.getOperand(1);
2082 
2083  if (Value *V = SimplifyVectorOp(I))
2084  return replaceInstUsesWith(I, V);
2085 
2086  if (Value *V = SimplifyOrInst(Op0, Op1, DL, &TLI, &DT, &AC))
2087  return replaceInstUsesWith(I, V);
2088 
2089  // (A&B)|(A&C) -> A&(B|C) etc
2090  if (Value *V = SimplifyUsingDistributiveLaws(I))
2091  return replaceInstUsesWith(I, V);
2092 
2093  // See if we can simplify any instructions used by the instruction whose sole
2094  // purpose is to compute bits we don't care about.
2095  if (SimplifyDemandedInstructionBits(I))
2096  return &I;
2097 
2098  if (Value *V = SimplifyBSwap(I))
2099  return replaceInstUsesWith(I, V);
2100 
2101  if (ConstantInt *RHS = dyn_cast<ConstantInt>(Op1)) {
2102  ConstantInt *C1 = nullptr; Value *X = nullptr;
2103  // (X & C1) | C2 --> (X | C2) & (C1|C2)
2104  // iff (C1 & C2) == 0.
2105  if (match(Op0, m_And(m_Value(X), m_ConstantInt(C1))) &&
2106  (RHS->getValue() & C1->getValue()) != 0 &&
2107  Op0->hasOneUse()) {
2108  Value *Or = Builder->CreateOr(X, RHS);
2109  Or->takeName(Op0);
2110  return BinaryOperator::CreateAnd(Or,
2111  Builder->getInt(RHS->getValue() | C1->getValue()));
2112  }
2113 
2114  // (X ^ C1) | C2 --> (X | C2) ^ (C1&~C2)
2115  if (match(Op0, m_Xor(m_Value(X), m_ConstantInt(C1))) &&
2116  Op0->hasOneUse()) {
2117  Value *Or = Builder->CreateOr(X, RHS);
2118  Or->takeName(Op0);
2119  return BinaryOperator::CreateXor(Or,
2120  Builder->getInt(C1->getValue() & ~RHS->getValue()));
2121  }
2122 
2123  if (Instruction *FoldedLogic = foldOpWithConstantIntoOperand(I))
2124  return FoldedLogic;
2125  }
2126 
2127  // Given an OR instruction, check to see if this is a bswap.
2128  if (Instruction *BSwap = MatchBSwap(I))
2129  return BSwap;
2130 
2131  Value *A = nullptr, *B = nullptr;
2132  ConstantInt *C1 = nullptr, *C2 = nullptr;
2133 
2134  // (X^C)|Y -> (X|Y)^C iff Y&C == 0
2135  if (Op0->hasOneUse() &&
2136  match(Op0, m_Xor(m_Value(A), m_ConstantInt(C1))) &&
2137  MaskedValueIsZero(Op1, C1->getValue(), 0, &I)) {
2138  Value *NOr = Builder->CreateOr(A, Op1);
2139  NOr->takeName(Op0);
2140  return BinaryOperator::CreateXor(NOr, C1);
2141  }
2142 
2143  // Y|(X^C) -> (X|Y)^C iff Y&C == 0
2144  if (Op1->hasOneUse() &&
2145  match(Op1, m_Xor(m_Value(A), m_ConstantInt(C1))) &&
2146  MaskedValueIsZero(Op0, C1->getValue(), 0, &I)) {
2147  Value *NOr = Builder->CreateOr(A, Op0);
2148  NOr->takeName(Op0);
2149  return BinaryOperator::CreateXor(NOr, C1);
2150  }
2151 
2152  // ((~A & B) | A) -> (A | B)
2153  if (match(Op0, m_And(m_Not(m_Value(A)), m_Value(B))) &&
2154  match(Op1, m_Specific(A)))
2155  return BinaryOperator::CreateOr(A, B);
2156 
2157  // ((A & B) | ~A) -> (~A | B)
2158  if (match(Op0, m_And(m_Value(A), m_Value(B))) &&
2159  match(Op1, m_Not(m_Specific(A))))
2160  return BinaryOperator::CreateOr(Builder->CreateNot(A), B);
2161 
2162  // (A & ~B) | (A ^ B) -> (A ^ B)
2163  // (~B & A) | (A ^ B) -> (A ^ B)
2164  if (match(Op0, m_c_And(m_Value(A), m_Not(m_Value(B)))) &&
2165  match(Op1, m_Xor(m_Specific(A), m_Specific(B))))
2166  return BinaryOperator::CreateXor(A, B);
2167 
2168  // Commute the 'or' operands.
2169  // (A ^ B) | (A & ~B) -> (A ^ B)
2170  // (A ^ B) | (~B & A) -> (A ^ B)
2171  if (match(Op1, m_c_And(m_Value(A), m_Not(m_Value(B)))) &&
2172  match(Op0, m_Xor(m_Specific(A), m_Specific(B))))
2173  return BinaryOperator::CreateXor(A, B);
2174 
2175  // (A & C)|(B & D)
2176  Value *C = nullptr, *D = nullptr;
2177  if (match(Op0, m_And(m_Value(A), m_Value(C))) &&
2178  match(Op1, m_And(m_Value(B), m_Value(D)))) {
2179  Value *V1 = nullptr, *V2 = nullptr;
2180  C1 = dyn_cast<ConstantInt>(C);
2181  C2 = dyn_cast<ConstantInt>(D);
2182  if (C1 && C2) { // (A & C1)|(B & C2)
2183  if ((C1->getValue() & C2->getValue()) == 0) {
2184  // ((V | N) & C1) | (V & C2) --> (V|N) & (C1|C2)
2185  // iff (C1&C2) == 0 and (N&~C1) == 0
2186  if (match(A, m_Or(m_Value(V1), m_Value(V2))) &&
2187  ((V1 == B &&
2188  MaskedValueIsZero(V2, ~C1->getValue(), 0, &I)) || // (V|N)
2189  (V2 == B &&
2190  MaskedValueIsZero(V1, ~C1->getValue(), 0, &I)))) // (N|V)
2191  return BinaryOperator::CreateAnd(A,
2192  Builder->getInt(C1->getValue()|C2->getValue()));
2193  // Or commutes, try both ways.
2194  if (match(B, m_Or(m_Value(V1), m_Value(V2))) &&
2195  ((V1 == A &&
2196  MaskedValueIsZero(V2, ~C2->getValue(), 0, &I)) || // (V|N)
2197  (V2 == A &&
2198  MaskedValueIsZero(V1, ~C2->getValue(), 0, &I)))) // (N|V)
2199  return BinaryOperator::CreateAnd(B,
2200  Builder->getInt(C1->getValue()|C2->getValue()));
2201 
2202  // ((V|C3)&C1) | ((V|C4)&C2) --> (V|C3|C4)&(C1|C2)
2203  // iff (C1&C2) == 0 and (C3&~C1) == 0 and (C4&~C2) == 0.
2204  ConstantInt *C3 = nullptr, *C4 = nullptr;
2205  if (match(A, m_Or(m_Value(V1), m_ConstantInt(C3))) &&
2206  (C3->getValue() & ~C1->getValue()) == 0 &&
2207  match(B, m_Or(m_Specific(V1), m_ConstantInt(C4))) &&
2208  (C4->getValue() & ~C2->getValue()) == 0) {
2209  V2 = Builder->CreateOr(V1, ConstantExpr::getOr(C3, C4), "bitfield");
2210  return BinaryOperator::CreateAnd(V2,
2211  Builder->getInt(C1->getValue()|C2->getValue()));
2212  }
2213  }
2214  }
2215 
2216  // Don't try to form a select if it's unlikely that we'll get rid of at
2217  // least one of the operands. A select is generally more expensive than the
2218  // 'or' that it is replacing.
2219  if (Op0->hasOneUse() || Op1->hasOneUse()) {
2220  // (Cond & C) | (~Cond & D) -> Cond ? C : D, and commuted variants.
2221  if (Value *V = matchSelectFromAndOr(A, C, B, D, *Builder))
2222  return replaceInstUsesWith(I, V);
2223  if (Value *V = matchSelectFromAndOr(A, C, D, B, *Builder))
2224  return replaceInstUsesWith(I, V);
2225  if (Value *V = matchSelectFromAndOr(C, A, B, D, *Builder))
2226  return replaceInstUsesWith(I, V);
2227  if (Value *V = matchSelectFromAndOr(C, A, D, B, *Builder))
2228  return replaceInstUsesWith(I, V);
2229  if (Value *V = matchSelectFromAndOr(B, D, A, C, *Builder))
2230  return replaceInstUsesWith(I, V);
2231  if (Value *V = matchSelectFromAndOr(B, D, C, A, *Builder))
2232  return replaceInstUsesWith(I, V);
2233  if (Value *V = matchSelectFromAndOr(D, B, A, C, *Builder))
2234  return replaceInstUsesWith(I, V);
2235  if (Value *V = matchSelectFromAndOr(D, B, C, A, *Builder))
2236  return replaceInstUsesWith(I, V);
2237  }
2238 
2239  // ((A&~B)|(~A&B)) -> A^B
2240  if ((match(C, m_Not(m_Specific(D))) &&
2241  match(B, m_Not(m_Specific(A)))))
2242  return BinaryOperator::CreateXor(A, D);
2243  // ((~B&A)|(~A&B)) -> A^B
2244  if ((match(A, m_Not(m_Specific(D))) &&
2245  match(B, m_Not(m_Specific(C)))))
2246  return BinaryOperator::CreateXor(C, D);
2247  // ((A&~B)|(B&~A)) -> A^B
2248  if ((match(C, m_Not(m_Specific(B))) &&
2249  match(D, m_Not(m_Specific(A)))))
2250  return BinaryOperator::CreateXor(A, B);
2251  // ((~B&A)|(B&~A)) -> A^B
2252  if ((match(A, m_Not(m_Specific(B))) &&
2253  match(D, m_Not(m_Specific(C)))))
2254  return BinaryOperator::CreateXor(C, B);
2255 
2256  // ((A|B)&1)|(B&-2) -> (A&1) | B
2257  if (match(A, m_Or(m_Value(V1), m_Specific(B))) ||
2258  match(A, m_Or(m_Specific(B), m_Value(V1)))) {
2259  Instruction *Ret = FoldOrWithConstants(I, Op1, V1, B, C);
2260  if (Ret) return Ret;
2261  }
2262  // (B&-2)|((A|B)&1) -> (A&1) | B
2263  if (match(B, m_Or(m_Specific(A), m_Value(V1))) ||
2264  match(B, m_Or(m_Value(V1), m_Specific(A)))) {
2265  Instruction *Ret = FoldOrWithConstants(I, Op0, A, V1, D);
2266  if (Ret) return Ret;
2267  }
2268  // ((A^B)&1)|(B&-2) -> (A&1) ^ B
2269  if (match(A, m_Xor(m_Value(V1), m_Specific(B))) ||
2270  match(A, m_Xor(m_Specific(B), m_Value(V1)))) {
2271  Instruction *Ret = FoldXorWithConstants(I, Op1, V1, B, C);
2272  if (Ret) return Ret;
2273  }
2274  // (B&-2)|((A^B)&1) -> (A&1) ^ B
2275  if (match(B, m_Xor(m_Specific(A), m_Value(V1))) ||
2276  match(B, m_Xor(m_Value(V1), m_Specific(A)))) {
2277  Instruction *Ret = FoldXorWithConstants(I, Op0, A, V1, D);
2278  if (Ret) return Ret;
2279  }
2280  }
2281 
2282  // (A ^ B) | ((B ^ C) ^ A) -> (A ^ B) | C
2283  if (match(Op0, m_Xor(m_Value(A), m_Value(B))))
2284  if (match(Op1, m_Xor(m_Xor(m_Specific(B), m_Value(C)), m_Specific(A))))
2285  if (Op1->hasOneUse() || cast<BinaryOperator>(Op1)->hasOneUse())
2286  return BinaryOperator::CreateOr(Op0, C);
2287 
2288  // ((A ^ C) ^ B) | (B ^ A) -> (B ^ A) | C
2289  if (match(Op0, m_Xor(m_Xor(m_Value(A), m_Value(C)), m_Value(B))))
2290  if (match(Op1, m_Xor(m_Specific(B), m_Specific(A))))
2291  if (Op0->hasOneUse() || cast<BinaryOperator>(Op0)->hasOneUse())
2292  return BinaryOperator::CreateOr(Op1, C);
2293 
2294  // ((B | C) & A) | B -> B | (A & C)
2295  if (match(Op0, m_And(m_Or(m_Specific(Op1), m_Value(C)), m_Value(A))))
2296  return BinaryOperator::CreateOr(Op1, Builder->CreateAnd(A, C));
2297 
2298  if (Instruction *DeMorgan = matchDeMorgansLaws(I, Builder))
2299  return DeMorgan;
2300 
2301  // Canonicalize xor to the RHS.
2302  bool SwappedForXor = false;
2303  if (match(Op0, m_Xor(m_Value(), m_Value()))) {
2304  std::swap(Op0, Op1);
2305  SwappedForXor = true;
2306  }
2307 
2308  // A | ( A ^ B) -> A | B
2309  // A | (~A ^ B) -> A | ~B
2310  // (A & B) | (A ^ B)
2311  if (match(Op1, m_Xor(m_Value(A), m_Value(B)))) {
2312  if (Op0 == A || Op0 == B)
2313  return BinaryOperator::CreateOr(A, B);
2314 
2315  if (match(Op0, m_And(m_Specific(A), m_Specific(B))) ||
2316  match(Op0, m_And(m_Specific(B), m_Specific(A))))
2317  return BinaryOperator::CreateOr(A, B);
2318 
2319  if (Op1->hasOneUse() && match(A, m_Not(m_Specific(Op0)))) {
2320  Value *Not = Builder->CreateNot(B, B->getName()+".not");
2321  return BinaryOperator::CreateOr(Not, Op0);
2322  }
2323  if (Op1->hasOneUse() && match(B, m_Not(m_Specific(Op0)))) {
2324  Value *Not = Builder->CreateNot(A, A->getName()+".not");
2325  return BinaryOperator::CreateOr(Not, Op0);
2326  }
2327  }
2328 
2329  // A | ~(A | B) -> A | ~B
2330  // A | ~(A ^ B) -> A | ~B
2331  if (match(Op1, m_Not(m_Value(A))))
2332  if (BinaryOperator *B = dyn_cast<BinaryOperator>(A))
2333  if ((Op0 == B->getOperand(0) || Op0 == B->getOperand(1)) &&
2334  Op1->hasOneUse() && (B->getOpcode() == Instruction::Or ||
2335  B->getOpcode() == Instruction::Xor)) {
2336  Value *NotOp = Op0 == B->getOperand(0) ? B->getOperand(1) :
2337  B->getOperand(0);
2338  Value *Not = Builder->CreateNot(NotOp, NotOp->getName()+".not");
2339  return BinaryOperator::CreateOr(Not, Op0);
2340  }
2341 
2342  // (A & B) | (~A ^ B) -> (~A ^ B)
2343  // (A & B) | (B ^ ~A) -> (~A ^ B)
2344  // (B & A) | (~A ^ B) -> (~A ^ B)
2345  // (B & A) | (B ^ ~A) -> (~A ^ B)
2346  // The match order is important: match the xor first because the 'not'
2347  // operation defines 'A'. We do not need to match the xor as Op0 because the
2348  // xor was canonicalized to Op1 above.
2349  if (match(Op1, m_c_Xor(m_Not(m_Value(A)), m_Value(B))) &&
2350  match(Op0, m_c_And(m_Specific(A), m_Specific(B))))
2351  return BinaryOperator::CreateXor(Builder->CreateNot(A), B);
2352 
2353  if (SwappedForXor)
2354  std::swap(Op0, Op1);
2355 
2356  {
2357  ICmpInst *LHS = dyn_cast<ICmpInst>(Op0);
2358  ICmpInst *RHS = dyn_cast<ICmpInst>(Op1);
2359  if (LHS && RHS)
2360  if (Value *Res = FoldOrOfICmps(LHS, RHS, &I))
2361  return replaceInstUsesWith(I, Res);
2362 
2363  // TODO: Make this recursive; it's a little tricky because an arbitrary
2364  // number of 'or' instructions might have to be created.
2365  Value *X, *Y;
2366  if (LHS && match(Op1, m_OneUse(m_Or(m_Value(X), m_Value(Y))))) {
2367  if (auto *Cmp = dyn_cast<ICmpInst>(X))
2368  if (Value *Res = FoldOrOfICmps(LHS, Cmp, &I))
2369  return replaceInstUsesWith(I, Builder->CreateOr(Res, Y));
2370  if (auto *Cmp = dyn_cast<ICmpInst>(Y))
2371  if (Value *Res = FoldOrOfICmps(LHS, Cmp, &I))
2372  return replaceInstUsesWith(I, Builder->CreateOr(Res, X));
2373  }
2374  if (RHS && match(Op0, m_OneUse(m_Or(m_Value(X), m_Value(Y))))) {
2375  if (auto *Cmp = dyn_cast<ICmpInst>(X))
2376  if (Value *Res = FoldOrOfICmps(Cmp, RHS, &I))
2377  return replaceInstUsesWith(I, Builder->CreateOr(Res, Y));
2378  if (auto *Cmp = dyn_cast<ICmpInst>(Y))
2379  if (Value *Res = FoldOrOfICmps(Cmp, RHS, &I))
2380  return replaceInstUsesWith(I, Builder->CreateOr(Res, X));
2381  }
2382  }
2383 
2384  // (fcmp uno x, c) | (fcmp uno y, c) -> (fcmp uno x, y)
2385  if (FCmpInst *LHS = dyn_cast<FCmpInst>(I.getOperand(0)))
2386  if (FCmpInst *RHS = dyn_cast<FCmpInst>(I.getOperand(1)))
2387  if (Value *Res = FoldOrOfFCmps(LHS, RHS))
2388  return replaceInstUsesWith(I, Res);
2389 
2390  if (Instruction *CastedOr = foldCastedBitwiseLogic(I))
2391  return CastedOr;
2392 
2393  // or(sext(A), B) / or(B, sext(A)) --> A ? -1 : B, where A is i1 or <N x i1>.
2394  if (match(Op0, m_OneUse(m_SExt(m_Value(A)))) &&
2395  A->getType()->getScalarType()->isIntegerTy(1))
2396  return SelectInst::Create(A, ConstantInt::getSigned(I.getType(), -1), Op1);
2397  if (match(Op1, m_OneUse(m_SExt(m_Value(A)))) &&
2398  A->getType()->getScalarType()->isIntegerTy(1))
2399  return SelectInst::Create(A, ConstantInt::getSigned(I.getType(), -1), Op0);
2400 
2401  // Note: If we've gotten to the point of visiting the outer OR, then the
2402  // inner one couldn't be simplified. If it was a constant, then it won't
2403  // be simplified by a later pass either, so we try swapping the inner/outer
2404  // ORs in the hopes that we'll be able to simplify it this way.
2405  // (X|C) | V --> (X|V) | C
2406  if (Op0->hasOneUse() && !isa<ConstantInt>(Op1) &&
2407  match(Op0, m_Or(m_Value(A), m_ConstantInt(C1)))) {
2408  Value *Inner = Builder->CreateOr(A, Op1);
2409  Inner->takeName(Op0);
2410  return BinaryOperator::CreateOr(Inner, C1);
2411  }
2412 
2413  // Change (or (bool?A:B),(bool?C:D)) --> (bool?(or A,C):(or B,D))
2414  // Since this OR statement hasn't been optimized further yet, we hope
2415  // that this transformation will allow the new ORs to be optimized.
2416  {
2417  Value *X = nullptr, *Y = nullptr;
2418  if (Op0->hasOneUse() && Op1->hasOneUse() &&
2419  match(Op0, m_Select(m_Value(X), m_Value(A), m_Value(B))) &&
2420  match(Op1, m_Select(m_Value(Y), m_Value(C), m_Value(D))) && X == Y) {
2421  Value *orTrue = Builder->CreateOr(A, C);
2422  Value *orFalse = Builder->CreateOr(B, D);
2423  return SelectInst::Create(X, orTrue, orFalse);
2424  }
2425  }
2426 
2427  return Changed ? &I : nullptr;
2428 }
2429 
2430 // FIXME: We use commutative matchers (m_c_*) for some, but not all, matches
2431 // here. We should standardize that construct where it is needed or choose some
2432 // other way to ensure that commutated variants of patterns are not missed.
2434  bool Changed = SimplifyAssociativeOrCommutative(I);
2435  Value *Op0 = I.getOperand(0), *Op1 = I.getOperand(1);
2436 
2437  if (Value *V = SimplifyVectorOp(I))
2438  return replaceInstUsesWith(I, V);
2439 
2440  if (Value *V = SimplifyXorInst(Op0, Op1, DL, &TLI, &DT, &AC))
2441  return replaceInstUsesWith(I, V);
2442 
2443  // (A&B)^(A&C) -> A&(B^C) etc
2444  if (Value *V = SimplifyUsingDistributiveLaws(I))
2445  return replaceInstUsesWith(I, V);
2446 
2447  // See if we can simplify any instructions used by the instruction whose sole
2448  // purpose is to compute bits we don't care about.
2449  if (SimplifyDemandedInstructionBits(I))
2450  return &I;
2451 
2452  if (Value *V = SimplifyBSwap(I))
2453  return replaceInstUsesWith(I, V);
2454 
2455  // Is this a ~ operation?
2456  if (Value *NotOp = dyn_castNotVal(&I)) {
2457  if (BinaryOperator *Op0I = dyn_cast<BinaryOperator>(NotOp)) {
2458  if (Op0I->getOpcode() == Instruction::And ||
2459  Op0I->getOpcode() == Instruction::Or) {
2460  // ~(~X & Y) --> (X | ~Y) - De Morgan's Law
2461  // ~(~X | Y) === (X & ~Y) - De Morgan's Law
2462  if (dyn_castNotVal(Op0I->getOperand(1)))
2463  Op0I->swapOperands();
2464  if (Value *Op0NotVal = dyn_castNotVal(Op0I->getOperand(0))) {
2465  Value *NotY =
2466  Builder->CreateNot(Op0I->getOperand(1),
2467  Op0I->getOperand(1)->getName()+".not");
2468  if (Op0I->getOpcode() == Instruction::And)
2469  return BinaryOperator::CreateOr(Op0NotVal, NotY);
2470  return BinaryOperator::CreateAnd(Op0NotVal, NotY);
2471  }
2472 
2473  // ~(X & Y) --> (~X | ~Y) - De Morgan's Law
2474  // ~(X | Y) === (~X & ~Y) - De Morgan's Law
2475  if (IsFreeToInvert(Op0I->getOperand(0),
2476  Op0I->getOperand(0)->hasOneUse()) &&
2477  IsFreeToInvert(Op0I->getOperand(1),
2478  Op0I->getOperand(1)->hasOneUse())) {
2479  Value *NotX =
2480  Builder->CreateNot(Op0I->getOperand(0), "notlhs");
2481  Value *NotY =
2482  Builder->CreateNot(Op0I->getOperand(1), "notrhs");
2483  if (Op0I->getOpcode() == Instruction::And)
2484  return BinaryOperator::CreateOr(NotX, NotY);
2485  return BinaryOperator::CreateAnd(NotX, NotY);
2486  }
2487 
2488  } else if (Op0I->getOpcode() == Instruction::AShr) {
2489  // ~(~X >>s Y) --> (X >>s Y)
2490  if (Value *Op0NotVal = dyn_castNotVal(Op0I->getOperand(0)))
2491  return BinaryOperator::CreateAShr(Op0NotVal, Op0I->getOperand(1));
2492  }
2493  }
2494  }
2495 
2496  if (Constant *RHS = dyn_cast<Constant>(Op1)) {
2497  if (RHS->isAllOnesValue() && Op0->hasOneUse())
2498  // xor (cmp A, B), true = not (cmp A, B) = !cmp A, B
2499  if (CmpInst *CI = dyn_cast<CmpInst>(Op0))
2500  return CmpInst::Create(CI->getOpcode(),
2501  CI->getInversePredicate(),
2502  CI->getOperand(0), CI->getOperand(1));
2503  }
2504 
2505  if (ConstantInt *RHS = dyn_cast<ConstantInt>(Op1)) {
2506  // fold (xor(zext(cmp)), 1) and (xor(sext(cmp)), -1) to ext(!cmp).
2507  if (CastInst *Op0C = dyn_cast<CastInst>(Op0)) {
2508  if (CmpInst *CI = dyn_cast<CmpInst>(Op0C->getOperand(0))) {
2509  if (CI->hasOneUse() && Op0C->hasOneUse()) {
2510  Instruction::CastOps Opcode = Op0C->getOpcode();
2511  if ((Opcode == Instruction::ZExt || Opcode == Instruction::SExt) &&
2512  (RHS == ConstantExpr::getCast(Opcode, Builder->getTrue(),
2513  Op0C->getDestTy()))) {
2514  CI->setPredicate(CI->getInversePredicate());
2515  return CastInst::Create(Opcode, CI, Op0C->getType());
2516  }
2517  }
2518  }
2519  }
2520 
2521  if (BinaryOperator *Op0I = dyn_cast<BinaryOperator>(Op0)) {
2522  // ~(c-X) == X-c-1 == X+(-c-1)
2523  if (Op0I->getOpcode() == Instruction::Sub && RHS->isAllOnesValue())
2524  if (Constant *Op0I0C = dyn_cast<Constant>(Op0I->getOperand(0))) {
2525  Constant *NegOp0I0C = ConstantExpr::getNeg(Op0I0C);
2526  Constant *ConstantRHS = ConstantExpr::getSub(NegOp0I0C,
2527  ConstantInt::get(I.getType(), 1));
2528  return BinaryOperator::CreateAdd(Op0I->getOperand(1), ConstantRHS);
2529  }
2530 
2531  if (ConstantInt *Op0CI = dyn_cast<ConstantInt>(Op0I->getOperand(1))) {
2532  if (Op0I->getOpcode() == Instruction::Add) {
2533  // ~(X-c) --> (-c-1)-X
2534  if (RHS->isAllOnesValue()) {
2535  Constant *NegOp0CI = ConstantExpr::getNeg(Op0CI);
2536  return BinaryOperator::CreateSub(
2537  ConstantExpr::getSub(NegOp0CI,
2538  ConstantInt::get(I.getType(), 1)),
2539  Op0I->getOperand(0));
2540  } else if (RHS->getValue().isSignBit()) {
2541  // (X + C) ^ signbit -> (X + C + signbit)
2542  Constant *C = Builder->getInt(RHS->getValue() + Op0CI->getValue());
2543  return BinaryOperator::CreateAdd(Op0I->getOperand(0), C);
2544 
2545  }
2546  } else if (Op0I->getOpcode() == Instruction::Or) {
2547  // (X|C1)^C2 -> X^(C1|C2) iff X&~C1 == 0
2548  if (MaskedValueIsZero(Op0I->getOperand(0), Op0CI->getValue(),
2549  0, &I)) {
2550  Constant *NewRHS = ConstantExpr::getOr(Op0CI, RHS);
2551  // Anything in both C1 and C2 is known to be zero, remove it from
2552  // NewRHS.
2553  Constant *CommonBits = ConstantExpr::getAnd(Op0CI, RHS);
2554  NewRHS = ConstantExpr::getAnd(NewRHS,
2555  ConstantExpr::getNot(CommonBits));
2556  Worklist.Add(Op0I);
2557  I.setOperand(0, Op0I->getOperand(0));
2558  I.setOperand(1, NewRHS);
2559  return &I;
2560  }
2561  } else if (Op0I->getOpcode() == Instruction::LShr) {
2562  // ((X^C1) >> C2) ^ C3 -> (X>>C2) ^ ((C1>>C2)^C3)
2563  // E1 = "X ^ C1"
2564  BinaryOperator *E1;
2565  ConstantInt *C1;
2566  if (Op0I->hasOneUse() &&
2567  (E1 = dyn_cast<BinaryOperator>(Op0I->getOperand(0))) &&
2568  E1->getOpcode() == Instruction::Xor &&
2569  (C1 = dyn_cast<ConstantInt>(E1->getOperand(1)))) {
2570  // fold (C1 >> C2) ^ C3
2571  ConstantInt *C2 = Op0CI, *C3 = RHS;
2572  APInt FoldConst = C1->getValue().lshr(C2->getValue());
2573  FoldConst ^= C3->getValue();
2574  // Prepare the two operands.
2575  Value *Opnd0 = Builder->CreateLShr(E1->getOperand(0), C2);
2576  Opnd0->takeName(Op0I);
2577  cast<Instruction>(Opnd0)->setDebugLoc(I.getDebugLoc());
2578  Value *FoldVal = ConstantInt::get(Opnd0->getType(), FoldConst);
2579 
2580  return BinaryOperator::CreateXor(Opnd0, FoldVal);
2581  }
2582  }
2583  }
2584  }
2585 
2586  if (Instruction *FoldedLogic = foldOpWithConstantIntoOperand(I))
2587  return FoldedLogic;
2588  }
2589 
2590  BinaryOperator *Op1I = dyn_cast<BinaryOperator>(Op1);
2591  if (Op1I) {
2592  Value *A, *B;
2593  if (match(Op1I, m_Or(m_Value(A), m_Value(B)))) {
2594  if (A == Op0) { // B^(B|A) == (A|B)^B
2595  Op1I->swapOperands();
2596  I.swapOperands();
2597  std::swap(Op0, Op1);
2598  } else if (B == Op0) { // B^(A|B) == (A|B)^B
2599  I.swapOperands(); // Simplified below.
2600  std::swap(Op0, Op1);
2601  }
2602  } else if (match(Op1I, m_And(m_Value(A), m_Value(B))) &&
2603  Op1I->hasOneUse()){
2604  if (A == Op0) { // A^(A&B) -> A^(B&A)
2605  Op1I->swapOperands();
2606  std::swap(A, B);
2607  }
2608  if (B == Op0) { // A^(B&A) -> (B&A)^A
2609  I.swapOperands(); // Simplified below.
2610  std::swap(Op0, Op1);
2611  }
2612  }
2613  }
2614 
2615  BinaryOperator *Op0I = dyn_cast<BinaryOperator>(Op0);
2616  if (Op0I) {
2617  Value *A, *B;
2618  if (match(Op0I, m_Or(m_Value(A), m_Value(B))) &&
2619  Op0I->hasOneUse()) {
2620  if (A == Op1) // (B|A)^B == (A|B)^B
2621  std::swap(A, B);
2622  if (B == Op1) // (A|B)^B == A & ~B
2623  return BinaryOperator::CreateAnd(A, Builder->CreateNot(Op1));
2624  } else if (match(Op0I, m_And(m_Value(A), m_Value(B))) &&
2625  Op0I->hasOneUse()){
2626  if (A == Op1) // (A&B)^A -> (B&A)^A
2627  std::swap(A, B);
2628  if (B == Op1 && // (B&A)^A == ~B & A
2629  !isa<ConstantInt>(Op1)) { // Canonical form is (B&C)^C
2630  return BinaryOperator::CreateAnd(Builder->CreateNot(A), Op1);
2631  }
2632  }
2633  }
2634 
2635  if (Op0I && Op1I) {
2636  Value *A, *B, *C, *D;
2637  // (A & B)^(A | B) -> A ^ B
2638  if (match(Op0I, m_And(m_Value(A), m_Value(B))) &&
2639  match(Op1I, m_Or(m_Value(C), m_Value(D)))) {
2640  if ((A == C && B == D) || (A == D && B == C))
2641  return BinaryOperator::CreateXor(A, B);
2642  }
2643  // (A | B)^(A & B) -> A ^ B
2644  if (match(Op0I, m_Or(m_Value(A), m_Value(B))) &&
2645  match(Op1I, m_And(m_Value(C), m_Value(D)))) {
2646  if ((A == C && B == D) || (A == D && B == C))
2647  return BinaryOperator::CreateXor(A, B);
2648  }
2649  // (A | ~B) ^ (~A | B) -> A ^ B
2650  // (~B | A) ^ (~A | B) -> A ^ B
2651  if (match(Op0I, m_c_Or(m_Value(A), m_Not(m_Value(B)))) &&
2652  match(Op1I, m_Or(m_Not(m_Specific(A)), m_Specific(B))))
2653  return BinaryOperator::CreateXor(A, B);
2654 
2655  // (~A | B) ^ (A | ~B) -> A ^ B
2656  if (match(Op0I, m_Or(m_Not(m_Value(A)), m_Value(B))) &&
2657  match(Op1I, m_Or(m_Specific(A), m_Not(m_Specific(B))))) {
2658  return BinaryOperator::CreateXor(A, B);
2659  }
2660  // (A & ~B) ^ (~A & B) -> A ^ B
2661  // (~B & A) ^ (~A & B) -> A ^ B
2662  if (match(Op0I, m_c_And(m_Value(A), m_Not(m_Value(B)))) &&
2663  match(Op1I, m_And(m_Not(m_Specific(A)), m_Specific(B))))
2664  return BinaryOperator::CreateXor(A, B);
2665 
2666  // (~A & B) ^ (A & ~B) -> A ^ B
2667  if (match(Op0I, m_And(m_Not(m_Value(A)), m_Value(B))) &&
2668  match(Op1I, m_And(m_Specific(A), m_Not(m_Specific(B))))) {
2669  return BinaryOperator::CreateXor(A, B);
2670  }
2671  // (A ^ C)^(A | B) -> ((~A) & B) ^ C
2672  if (match(Op0I, m_Xor(m_Value(D), m_Value(C))) &&
2673  match(Op1I, m_Or(m_Value(A), m_Value(B)))) {
2674  if (D == A)
2675  return BinaryOperator::CreateXor(
2676  Builder->CreateAnd(Builder->CreateNot(A), B), C);
2677  if (D == B)
2678  return BinaryOperator::CreateXor(
2679  Builder->CreateAnd(Builder->CreateNot(B), A), C);
2680  }
2681  // (A | B)^(A ^ C) -> ((~A) & B) ^ C
2682  if (match(Op0I, m_Or(m_Value(A), m_Value(B))) &&
2683  match(Op1I, m_Xor(m_Value(D), m_Value(C)))) {
2684  if (D == A)
2685  return BinaryOperator::CreateXor(
2686  Builder->CreateAnd(Builder->CreateNot(A), B), C);
2687  if (D == B)
2688  return BinaryOperator::CreateXor(
2689  Builder->CreateAnd(Builder->CreateNot(B), A), C);
2690  }
2691  // (A & B) ^ (A ^ B) -> (A | B)
2692  if (match(Op0I, m_And(m_Value(A), m_Value(B))) &&
2693  match(Op1I, m_Xor(m_Specific(A), m_Specific(B))))
2694  return BinaryOperator::CreateOr(A, B);
2695  // (A ^ B) ^ (A & B) -> (A | B)
2696  if (match(Op0I, m_Xor(m_Value(A), m_Value(B))) &&
2697  match(Op1I, m_And(m_Specific(A), m_Specific(B))))
2698  return BinaryOperator::CreateOr(A, B);
2699  }
2700 
2701  // (A & ~B) ^ ~A -> ~(A & B)
2702  // (~B & A) ^ ~A -> ~(A & B)
2703  Value *A, *B;
2704  if (match(Op0, m_c_And(m_Value(A), m_Not(m_Value(B)))) &&
2705  match(Op1, m_Not(m_Specific(A))))
2706  return BinaryOperator::CreateNot(Builder->CreateAnd(A, B));
2707 
2708  // (icmp1 A, B) ^ (icmp2 A, B) --> (icmp3 A, B)
2709  if (ICmpInst *RHS = dyn_cast<ICmpInst>(I.getOperand(1)))
2710  if (ICmpInst *LHS = dyn_cast<ICmpInst>(I.getOperand(0)))
2711  if (PredicatesFoldable(LHS->getPredicate(), RHS->getPredicate())) {
2712  if (LHS->getOperand(0) == RHS->getOperand(1) &&
2713  LHS->getOperand(1) == RHS->getOperand(0))
2714  LHS->swapOperands();
2715  if (LHS->getOperand(0) == RHS->getOperand(0) &&
2716  LHS->getOperand(1) == RHS->getOperand(1)) {
2717  Value *Op0 = LHS->getOperand(0), *Op1 = LHS->getOperand(1);
2718  unsigned Code = getICmpCode(LHS) ^ getICmpCode(RHS);
2719  bool isSigned = LHS->isSigned() || RHS->isSigned();
2720  return replaceInstUsesWith(I,
2721  getNewICmpValue(isSigned, Code, Op0, Op1,
2722  Builder));
2723  }
2724  }
2725 
2726  if (Instruction *CastedXor = foldCastedBitwiseLogic(I))
2727  return CastedXor;
2728 
2729  return Changed ? &I : nullptr;
2730 }
Value * FoldOrOfICmps(ICmpInst *LHS, ICmpInst *RHS, Instruction *CxtI)
Fold (icmp)|(icmp) if possible.
static unsigned getBitWidth(Type *Ty, const DataLayout &DL)
Returns the bitwidth of the given scalar or pointer type (if unknown returns 0).
BinaryOp_match< LHS, RHS, Instruction::And > m_And(const LHS &L, const RHS &R)
Definition: PatternMatch.h:506
static ConstantInt * getFalse(LLVMContext &Context)
Definition: Constants.cpp:513
Value * FoldAndOfICmps(ICmpInst *LHS, ICmpInst *RHS)
Fold (icmp)&(icmp) if possible.
IntegerType * getType() const
getType - Specialize the getType() method to always return an IntegerType, which reduces the amount o...
Definition: Constants.h:177
bool isKnownToBeAPowerOfTwo(const Value *V, const DataLayout &DL, bool OrZero=false, unsigned Depth=0, AssumptionCache *AC=nullptr, const Instruction *CxtI=nullptr, const DominatorTree *DT=nullptr)
Return true if the given value is known to have exactly one bit set when defined. ...
Instruction::CastOps getOpcode() const
Return the opcode of this CastInst.
Definition: InstrTypes.h:840
class_match< Value > m_Value()
Match an arbitrary value and ignore it.
Definition: PatternMatch.h:64
Value * CreateICmp(CmpInst::Predicate P, Value *LHS, Value *RHS, const Twine &Name="")
Definition: IRBuilder.h:1554
This class is the base class for the comparison instructions.
Definition: InstrTypes.h:870
APInt byteSwap() const
Definition: APInt.cpp:744
static bool IsFreeToInvert(Value *V, bool WillInvertAllUses)
Return true if the specified value is free to invert (apply ~ to).
Instruction * visitXor(BinaryOperator &I)
Value * CreateBinOp(Instruction::BinaryOps Opc, Value *LHS, Value *RHS, const Twine &Name="", MDNode *FPMathTag=nullptr)
Definition: IRBuilder.h:1032
Instruction * visitOr(BinaryOperator &I)
static BinaryOperator * CreateNot(Value *Op, const Twine &Name="", Instruction *InsertBefore=nullptr)
static Type * makeCmpResultType(Type *opnd_type)
Create a result type for fcmp/icmp.
Definition: InstrTypes.h:1112
bool decomposeBitTestICmp(const ICmpInst *I, CmpInst::Predicate &Pred, Value *&X, Value *&Y, Value *&Z)
Decompose an icmp into the form ((X & Y) pred Z) if possible.
size_t i
Value * CreateXor(Value *LHS, Value *RHS, const Twine &Name="")
Definition: IRBuilder.h:1019
match_zero m_Zero()
Match an arbitrary zero/null constant.
Definition: PatternMatch.h:137
static unsigned getFCmpCode(FCmpInst::Predicate CC)
Similar to getICmpCode but for FCmpInst.
This class represents zero extension of integer types.
unsigned getNumOperands() const
Definition: User.h:167
static Value * foldLogOpOfMaskedICmps(ICmpInst *LHS, ICmpInst *RHS, bool IsAnd, llvm::InstCombiner::BuilderTy *Builder)
Try to fold (icmp(A & B) ==/!= C) &/| (icmp(A & D) ==/!= E) into a single (icmp(A & X) ==/!= Y)...
match_combine_or< BinaryOp_match< LHS, RHS, Instruction::Xor >, BinaryOp_match< RHS, LHS, Instruction::Xor > > m_c_Xor(const LHS &L, const RHS &R)
Matches an Xor with LHS and RHS in either order.
unsigned getICmpCode(const ICmpInst *ICI, bool InvertPred=false)
Encode a icmp predicate into a three bit mask.
static bool areInverseVectorBitmasks(Constant *C1, Constant *C2)
If all elements of two constant vectors are 0/-1 and inverses, return true.
static APInt getLowBitsSet(unsigned numBits, unsigned loBitsSet)
Get a value with low bits set.
Definition: APInt.h:536
Predicate getInversePredicate() const
For example, EQ -> NE, UGT -> ULE, SLT -> SGE, OEQ -> UNE, UGT -> OLE, OLT -> UGE, etc.
Definition: InstrTypes.h:984
class_match< Constant > m_Constant()
Match an arbitrary Constant and ignore it.
Definition: PatternMatch.h:83
unsigned less or equal
Definition: InstrTypes.h:906
unsigned less than
Definition: InstrTypes.h:905
bool isSigned() const
Determine if this instruction is using a signed comparison.
Definition: InstrTypes.h:1027
0 1 0 0 True if ordered and less than
Definition: InstrTypes.h:886
static SelectInst * Create(Value *C, Value *S1, Value *S2, const Twine &NameStr="", Instruction *InsertBefore=nullptr, Instruction *MDFrom=nullptr)
static Value * getFCmpValue(unsigned Code, Value *LHS, Value *RHS, InstCombiner::BuilderTy *Builder)
This is the complement of getFCmpCode, which turns an opcode and two operands into either a FCmp inst...
1 1 1 0 True if unordered or not equal
Definition: InstrTypes.h:896
static CastInst * CreateBitOrPointerCast(Value *S, Type *Ty, const Twine &Name="", Instruction *InsertBefore=nullptr)
Create a BitCast, a PtrToInt, or an IntToPTr cast instruction.
MaskedICmpType
enum for classifying (icmp eq (A & B), C) and (icmp ne (A & B), C) One of A and B is considered the m...
unsigned getBitWidth() const
Get the number of bits in this IntegerType.
Definition: DerivedTypes.h:65
#define R2(n)
static Constant * getTrue(Type *Ty)
For a boolean type, or a vector of boolean type, return true, or a vector with every element true...
static Constant * getSub(Constant *C1, Constant *C2, bool HasNUW=false, bool HasNSW=false)
Definition: Constants.cpp:2143
match_combine_or< BinaryOp_match< LHS, RHS, Instruction::And >, BinaryOp_match< RHS, LHS, Instruction::And > > m_c_And(const LHS &L, const RHS &R)
Matches an And with LHS and RHS in either order.
bool isMinusOne() const
This function will return true iff every bit in this constant is set to true.
Definition: Constants.h:214
static Constant * getNullValue(Type *Ty)
Constructor to create a '0' constant of arbitrary type.
Definition: Constants.cpp:195
StringRef getName() const
Return a constant reference to the value's name.
Definition: Value.cpp:191
bool swapOperands()
Exchange the two operands to this instruction.
APInt Not(const APInt &APIVal)
Bitwise complement function.
Definition: APInt.h:1957
1 0 0 1 True if unordered or equal
Definition: InstrTypes.h:891
bool match(Val *V, const Pattern &P)
Definition: PatternMatch.h:41
match_combine_or< BinaryOp_match< LHS, RHS, Instruction::Or >, BinaryOp_match< RHS, LHS, Instruction::Or > > m_c_Or(const LHS &L, const RHS &R)
Matches an Or with LHS and RHS in either order.
1 0 0 0 True if unordered: isnan(X) | isnan(Y)
Definition: InstrTypes.h:890
BinaryOp_match< LHS, RHS, Instruction::Xor > m_Xor(const LHS &L, const RHS &R)
Definition: PatternMatch.h:518
This is the base class for all instructions that perform data casts.
Definition: InstrTypes.h:578
const APInt & getValue() const
Return the constant as an APInt value reference.
Definition: Constants.h:143
APInt lshr(unsigned shiftAmt) const
Logical right-shift function.
Definition: APInt.cpp:1122
static GCRegistry::Add< StatepointGC > D("statepoint-example","an example strategy for statepoint")
CastClass_match< OpTy, Instruction::Trunc > m_Trunc(const OpTy &Op)
Matches Trunc.
Definition: PatternMatch.h:801
This provides a uniform API for creating instructions and inserting them into a basic block: either a...
Definition: IRBuilder.h:588
static Constant * AddOne(Constant *C)
Add one to a Constant.
0 1 0 1 True if ordered and less than or equal
Definition: InstrTypes.h:887
bool isShiftedMask(unsigned numBits, const APInt &APIVal)
Return true if the argument APInt value contains a sequence of ones with the remainder zero...
Definition: APInt.h:1826
Instruction * FoldOrWithConstants(BinaryOperator &I, Value *Op, Value *A, Value *B, Value *C)
This helper function folds:
not_match< LHS > m_Not(const LHS &L)
Definition: PatternMatch.h:854
BinaryOp_match< LHS, RHS, Instruction::Add > m_Add(const LHS &L, const RHS &R)
Definition: PatternMatch.h:434
static unsigned foldLogOpOfMaskedICmpsHelper(Value *&A, Value *&B, Value *&C, Value *&D, Value *&E, ICmpInst *LHS, ICmpInst *RHS, ICmpInst::Predicate &LHSCC, ICmpInst::Predicate &RHSCC)
Handle (icmp(A & B) ==/!= C) &/| (icmp(A & D) ==/!= E) Return the set of pattern classes (from Masked...
static Constant * getZExt(Constant *C, Type *Ty, bool OnlyIfReduced=false)
Definition: Constants.cpp:1587
Value * CreateBitCast(Value *V, Type *DestTy, const Twine &Name="")
Definition: IRBuilder.h:1362
#define F(x, y, z)
Definition: MD5.cpp:51
LLVMContext & getContext() const
Return the LLVMContext in which this type was uniqued.
Definition: Type.h:128
match_combine_or< LTy, RTy > m_CombineOr(const LTy &L, const RTy &R)
Combine two pattern matchers matching L || R.
Definition: PatternMatch.h:117
static Instruction * foldLogicCastConstant(BinaryOperator &Logic, CastInst *Cast, InstCombiner::BuilderTy *Builder)
Fold {and,or,xor} (cast X), C.
CastClass_match< OpTy, Instruction::ZExt > m_ZExt(const OpTy &Op)
Matches ZExt.
Definition: PatternMatch.h:813
This instruction compares its operands according to the predicate given to the constructor.
uint64_t getLimitedValue(uint64_t Limit=~0ULL) const
getLimitedValue - If the value is smaller than the specified limit, return it, otherwise return the l...
Definition: Constants.h:256
bool sgt(const APInt &RHS) const
Signed greather than comparison.
Definition: APInt.h:1101
static CmpInst * Create(OtherOps Op, Predicate predicate, Value *S1, Value *S2, const Twine &Name="", Instruction *InsertBefore=nullptr)
Construct a compare instruction, given the opcode, the predicate and the two operands.
unsigned getActiveBits() const
Compute the number of active bits in the value.
Definition: APInt.h:1279
class_match< ConstantInt > m_ConstantInt()
Match an arbitrary ConstantInt and ignore it.
Definition: PatternMatch.h:75
Function * getDeclaration(Module *M, ID id, ArrayRef< Type * > Tys=None)
Create or insert an LLVM Function declaration for an intrinsic, and return it.
Definition: Function.cpp:949
static GCRegistry::Add< OcamlGC > B("ocaml","ocaml 3.10-compatible GC")
SelectClass_match< Cond, LHS, RHS > m_Select(const Cond &C, const LHS &L, const RHS &R)
Definition: PatternMatch.h:758
void takeName(Value *V)
Transfer the name from V to this value.
Definition: Value.cpp:263
Type * getScalarType() const LLVM_READONLY
If this is a vector type, return the element type, otherwise return 'this'.
Definition: Type.cpp:44
static BinaryOperator * CreateAdd(Value *S1, Value *S2, const Twine &Name, Instruction *InsertBefore, Value *FlagsOp)
static const Value * getNotArgument(const Value *BinOp)
bool ult(const APInt &RHS) const
Unsigned less than comparison.
Definition: APInt.cpp:501
static GCRegistry::Add< CoreCLRGC > E("coreclr","CoreCLR-compatible GC")
Value * CreateOr(Value *LHS, Value *RHS, const Twine &Name="")
Definition: IRBuilder.h:1003
static APInt getHighBitsSet(unsigned numBits, unsigned hiBitsSet)
Get a value with high bits set.
Definition: APInt.h:518
Value * SimplifyOrInst(Value *LHS, Value *RHS, const DataLayout &DL, const TargetLibraryInfo *TLI=nullptr, const DominatorTree *DT=nullptr, AssumptionCache *AC=nullptr, const Instruction *CxtI=nullptr)
Given operands for an Or, fold the result or return null.
static Constant * getBitCast(Constant *C, Type *Ty, bool OnlyIfReduced=false)
Definition: Constants.cpp:1695
Value * CreateFCmp(CmpInst::Predicate P, Value *LHS, Value *RHS, const Twine &Name="", MDNode *FPMathTag=nullptr)
Definition: IRBuilder.h:1561
OneUse_match< T > m_OneUse(const T &SubPattern)
Definition: PatternMatch.h:55
bool isIntOrIntVectorTy() const
Return true if this is an integer type or a vector of integer types.
Definition: Type.h:201
static Value * getSelectCondition(Value *A, Value *B, InstCombiner::BuilderTy &Builder)
We have an expression of the form (A & C) | (B & D).
The instances of the Type class are immutable: once they are created, they are never changed...
Definition: Type.h:45
BinaryOp_match< LHS, RHS, Instruction::Or > m_Or(const LHS &L, const RHS &R)
Definition: PatternMatch.h:512
bool isVectorTy() const
True if this is an instance of VectorType.
Definition: Type.h:219
bool isEquality() const
Return true if this predicate is either EQ or NE.
CastClass_match< OpTy, Instruction::BitCast > m_BitCast(const OpTy &Op)
Matches BitCast.
Definition: PatternMatch.h:789
This is an important base class in LLVM.
Definition: Constant.h:42
Value * FoldAndOfFCmps(FCmpInst *LHS, FCmpInst *RHS)
Optimize (fcmp)&(fcmp).
Value * CreateSelect(Value *C, Value *True, Value *False, const Twine &Name="", Instruction *MDFrom=nullptr)
Definition: IRBuilder.h:1609
bool MaskedValueIsZero(const Value *V, const APInt &Mask, const DataLayout &DL, unsigned Depth=0, AssumptionCache *AC=nullptr, const Instruction *CxtI=nullptr, const DominatorTree *DT=nullptr)
Return true if 'V & Mask' is known to be zero.
static Constant * getAnd(Constant *C1, Constant *C2)
Definition: Constants.cpp:2191
APInt Or(const APInt &LHS, const APInt &RHS)
Bitwise OR function for APInt.
Definition: APInt.h:1947
ConstantFP - Floating Point Values [float, double].
Definition: Constants.h:269
APInt Xor(const APInt &LHS, const APInt &RHS)
Bitwise XOR function for APInt.
Definition: APInt.h:1952
cst_pred_ty< is_all_ones > m_AllOnes()
Match an integer or vector with all bits set to true.
Definition: PatternMatch.h:252
specificval_ty m_Specific(const Value *V)
Match if we have a specific specified value.
Definition: PatternMatch.h:322
const DebugLoc & getDebugLoc() const
Return the debug location for this node as a DebugLoc.
Definition: Instruction.h:259
bool sle(const APInt &RHS) const
Signed less or equal comparison.
Definition: APInt.h:1067
static GCMetadataPrinterRegistry::Add< ErlangGCPrinter > X("erlang","erlang-compatible garbage collector")
This instruction compares its operands according to the predicate given to the constructor.
Predicate
This enumeration lists the possible predicates for CmpInst subclasses.
Definition: InstrTypes.h:880
unsigned getBitWidth() const
Return the number of bits in the APInt.
Definition: APInt.h:1255
Value * getOperand(unsigned i) const
Definition: User.h:145
0 1 1 1 True if ordered (no nans)
Definition: InstrTypes.h:889
static bool isNot(const Value *V)
Class to represent integer types.
Definition: DerivedTypes.h:39
Type * getSrcTy() const
Return the source type, as a convenience.
Definition: InstrTypes.h:845
unsigned countPopulation() const
Count the number of bits set.
Definition: APInt.h:1397
static unsigned conjugateICmpMask(unsigned Mask)
Convert an analysis of a masked ICmp into its equivalent if all boolean operations had the opposite s...
Predicate getPredicate() const
Return the predicate for this instruction.
Definition: InstrTypes.h:960
static Constant * getNot(Constant *C)
Definition: Constants.cpp:2126
Constant * getAggregateElement(unsigned Elt) const
For aggregates (struct/array/vector) return the constant that corresponds to the specified element if...
Definition: Constants.cpp:265
static Constant * getAllOnesValue(Type *Ty)
Get the all ones value.
Definition: Constants.cpp:249
1 1 1 1 Always true (always folded)
Definition: InstrTypes.h:897
void swapOperands()
Exchange the two operands to this instruction in such a way that it does not modify the semantics of ...
bool isPowerOf2() const
Check if this APInt's value is a power of two greater than zero.
Definition: APInt.h:391
1 1 0 1 True if unordered, less than, or equal
Definition: InstrTypes.h:895
#define llvm_unreachable(msg)
Marks that the current location is not supposed to be reachable.
static Instruction * foldBoolSextMaskToSelect(BinaryOperator &I)
signed greater than
Definition: InstrTypes.h:907
Instruction * visitAnd(BinaryOperator &I)
CastClass_match< OpTy, Instruction::SExt > m_SExt(const OpTy &Op)
Matches SExt.
Definition: PatternMatch.h:807
bool ugt(const APInt &RHS) const
Unsigned greather than comparison.
Definition: APInt.h:1083
0 0 1 0 True if ordered and greater than
Definition: InstrTypes.h:884
BinaryOps getOpcode() const
Definition: InstrTypes.h:541
This is the shared class of boolean and integer constants.
Definition: Constants.h:88
const Module * getModule() const
Return the module owning the function this instruction belongs to or nullptr it the function does not...
Definition: Instruction.cpp:58
This is a 'vector' (really, a variable-sized array), optimized for the case when the array is small...
Definition: SmallVector.h:843
1 1 0 0 True if unordered or less than
Definition: InstrTypes.h:894
Type * getType() const
All values are typed, get the type of this value.
Definition: Value.h:230
BinOp2_match< LHS, RHS, Instruction::LShr, Instruction::Shl > m_LogicalShift(const LHS &L, const RHS &R)
Matches LShr or Shl.
Definition: PatternMatch.h:665
signed less than
Definition: InstrTypes.h:909
Type * getDestTy() const
Return the destination type, as a convenience.
Definition: InstrTypes.h:847
LLVM_NODISCARD T pop_back_val()
Definition: SmallVector.h:382
Predicate getSwappedPredicate() const
For example, EQ->EQ, SLE->SGE, ULT->UGT, OEQ->OEQ, ULE->UGE, OLT->OGT, etc.
Definition: InstrTypes.h:1000
static Constant * getTrunc(Constant *C, Type *Ty, bool OnlyIfReduced=false)
Definition: Constants.cpp:1559
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:558
static ConstantInt * getSigned(IntegerType *Ty, int64_t V)
Return a ConstantInt with the specified value for the specified type.
Definition: Constants.cpp:572
bool isZero() const
This is just a convenience method to make client code smaller for a common code.
Definition: Constants.h:198
bool isNullValue() const
Return true if this is the value that would be returned by getNullValue.
Definition: Constants.cpp:90
bool PredicatesFoldable(CmpInst::Predicate p1, CmpInst::Predicate p2)
Return true if both predicates match sign or if at least one of them is an equality comparison (which...
static GCRegistry::Add< ShadowStackGC > C("shadow-stack","Very portable GC for uncooperative code generators")
void setOperand(unsigned i, Value *Val)
Definition: User.h:150
void swap(llvm::BitVector &LHS, llvm::BitVector &RHS)
Implement std::swap in terms of BitVector swap.
Definition: BitVector.h:586
signed less or equal
Definition: InstrTypes.h:910
Class for arbitrary precision integers.
Definition: APInt.h:77
bool isIntegerTy() const
True if this is an instance of IntegerType.
Definition: Type.h:195
static BinaryOperator * Create(BinaryOps Op, Value *S1, Value *S2, const Twine &Name=Twine(), Instruction *InsertBefore=nullptr)
Construct a binary instruction, given the opcode and the two operands.
unsigned getVectorNumElements() const
Definition: DerivedTypes.h:438
static Constant * getCast(unsigned ops, Constant *C, Type *Ty, bool OnlyIfReduced=false)
Convenience function for getting a Cast operation.
Definition: Constants.cpp:1452
bool isMinValue() const
Determine if this is the smallest unsigned value.
Definition: APInt.h:366
APInt And(const APInt &LHS, const APInt &RHS)
Bitwise AND function for APInt.
Definition: APInt.h:1942
void removeFromParent()
This method unlinks 'this' from the containing basic block, but does not delete it.
Definition: Instruction.cpp:72
static Constant * getNeg(Constant *C, bool HasNUW=false, bool HasNSW=false)
Definition: Constants.cpp:2113
bool isAllOnesValue() const
Determine if all bits are set.
Definition: APInt.h:342
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 ...
void ComputeSignBit(const Value *V, bool &KnownZero, bool &KnownOne, const DataLayout &DL, unsigned Depth=0, AssumptionCache *AC=nullptr, const Instruction *CxtI=nullptr, const DominatorTree *DT=nullptr)
Determine whether the sign bit is known to be zero or one.
bool isMinSignedValue() const
Determine if this is the smallest signed value.
Definition: APInt.h:372
Value * SimplifyAndInst(Value *LHS, Value *RHS, const DataLayout &DL, const TargetLibraryInfo *TLI=nullptr, const DominatorTree *DT=nullptr, AssumptionCache *AC=nullptr, const Instruction *CxtI=nullptr)
Given operands for an And, fold the result or return null.
Value * getICmpValue(bool Sign, unsigned Code, Value *LHS, Value *RHS, CmpInst::Predicate &NewICmpPred)
This is the complement of getICmpCode, which turns an opcode and two operands into either a constant ...
unsigned greater or equal
Definition: InstrTypes.h:904
static Value * dyn_castNotVal(Value *V)
#define I(x, y, z)
Definition: MD5.cpp:54
#define N
static Constant * getOr(Constant *C1, Constant *C2)
Definition: Constants.cpp:2195
bool hasOneUse() const
Return true if there is exactly one user of this value.
Definition: Value.h:383
0 1 1 0 True if ordered and operands are unequal
Definition: InstrTypes.h:888
bool recognizeBSwapOrBitReverseIdiom(Instruction *I, bool MatchBSwaps, bool MatchBitReversals, SmallVectorImpl< Instruction * > &InsertedInsts)
Try and match a bswap or bitreverse idiom.
Definition: Local.cpp:1994
LLVM_NODISCARD std::enable_if<!is_simple_type< Y >::value, typename cast_retty< X, const Y >::ret_type >::type dyn_cast(const Y &Val)
Definition: Casting.h:287
static volatile int Zero
1 0 1 0 True if unordered or greater than
Definition: InstrTypes.h:892
Value * CreateAnd(Value *LHS, Value *RHS, const Twine &Name="")
Definition: IRBuilder.h:987
OtherOps getOpcode() const
Get the opcode casted to the right type.
Definition: InstrTypes.h:955
Value * SimplifyXorInst(Value *LHS, Value *RHS, const DataLayout &DL, const TargetLibraryInfo *TLI=nullptr, const DominatorTree *DT=nullptr, AssumptionCache *AC=nullptr, const Instruction *CxtI=nullptr)
Given operands for an Xor, fold the result or return null.
assert(ImpDefSCC.getReg()==AMDGPU::SCC &&ImpDefSCC.isDef())
static bool isRunOfOnes(unsigned Val, unsigned &MB, unsigned &ME)
Returns true iff Val consists of one contiguous run of 1s with any number of 0s on either side...
0 0 0 1 True if ordered and equal
Definition: InstrTypes.h:883
LLVM Value Representation.
Definition: Value.h:71
This file provides internal interfaces used to implement the InstCombine.
1 0 1 1 True if unordered, greater than, or equal
Definition: InstrTypes.h:893
unsigned getOpcode() const
Returns a member of one of the enums like Instruction::Add.
Definition: Instruction.h:111
std::underlying_type< E >::type Mask()
Get a bitmask with 1s in all places up to the high-order bit of E's largest value.
Definition: BitmaskEnum.h:81
static Value * getNewICmpValue(bool Sign, unsigned Code, Value *LHS, Value *RHS, InstCombiner::BuilderTy *Builder)
This is the complement of getICmpCode, which turns an opcode and two operands into either a constant ...
unsigned countLeadingZeros() const
The APInt version of the countLeadingZeros functions in MathExtras.h.
Definition: APInt.h:1343
Predicate getSignedPredicate() const
For example, EQ->EQ, SLE->SLE, UGT->SGT, etc.
unsigned greater than
Definition: InstrTypes.h:903
APInt zext(unsigned width) const
Zero extend to a new width.
Definition: APInt.cpp:980
Value * simplifyRangeCheck(ICmpInst *Cmp0, ICmpInst *Cmp1, bool Inverted)
Try to fold a signed range checked with lower bound 0 to an unsigned icmp.
static GCMetadataPrinterRegistry::Add< OcamlGCMetadataPrinter > Y("ocaml","ocaml 3.10-compatible collector")
bool isBitwiseLogicOp() const
Return true if this is and/or/xor.
Definition: Instruction.h:146
0 0 1 1 True if ordered and greater than or equal
Definition: InstrTypes.h:885
static Value * matchSelectFromAndOr(Value *A, Value *C, Value *B, Value *D, InstCombiner::BuilderTy &Builder)
We have an expression of the form (A & C) | (B & D).
static GCRegistry::Add< ErlangGC > A("erlang","erlang-compatible garbage collector")
static Instruction * matchDeMorgansLaws(BinaryOperator &I, InstCombiner::BuilderTy *Builder)
Match De Morgan's Laws: (~A & ~B) == (~(A | B)) (~A | ~B) == (~(A & B))
bool ule(const APInt &RHS) const
Unsigned less or equal comparison.
Definition: APInt.h:1051
Instruction * FoldXorWithConstants(BinaryOperator &I, Value *Op, Value *A, Value *B, Value *C)
This helper function folds:
static Constant * SubOne(Constant *C)
Subtract one from a Constant.
static unsigned getTypeOfMaskedICmp(Value *A, Value *B, Value *C, ICmpInst::Predicate SCC)
Return the set of pattern classes (from MaskedICmpType) that (icmp SCC (A & B), C) satisfies...
0 0 0 0 Always false (always folded)
Definition: InstrTypes.h:882
signed greater or equal
Definition: InstrTypes.h:908
A wrapper class for inspecting calls to intrinsic functions.
Definition: IntrinsicInst.h:44
static Constant * getXor(Constant *C1, Constant *C2)
Definition: Constants.cpp:2199
Value * FoldOrOfFCmps(FCmpInst *LHS, FCmpInst *RHS)
Optimize (fcmp)|(fcmp).