LLVM  10.0.0svn
ConstantFolding.cpp
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1 //===-- ConstantFolding.cpp - Fold instructions into constants ------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 // This file defines routines for folding instructions into constants.
10 //
11 // Also, to supplement the basic IR ConstantExpr simplifications,
12 // this file defines some additional folding routines that can make use of
13 // DataLayout information. These functions cannot go in IR due to library
14 // dependency issues.
15 //
16 //===----------------------------------------------------------------------===//
17 
19 #include "llvm/ADT/APFloat.h"
20 #include "llvm/ADT/APInt.h"
21 #include "llvm/ADT/ArrayRef.h"
22 #include "llvm/ADT/DenseMap.h"
23 #include "llvm/ADT/STLExtras.h"
24 #include "llvm/ADT/SmallVector.h"
25 #include "llvm/ADT/StringRef.h"
29 #include "llvm/Config/config.h"
30 #include "llvm/IR/Constant.h"
31 #include "llvm/IR/Constants.h"
32 #include "llvm/IR/DataLayout.h"
33 #include "llvm/IR/DerivedTypes.h"
34 #include "llvm/IR/Function.h"
35 #include "llvm/IR/GlobalValue.h"
36 #include "llvm/IR/GlobalVariable.h"
37 #include "llvm/IR/InstrTypes.h"
38 #include "llvm/IR/Instruction.h"
39 #include "llvm/IR/Instructions.h"
40 #include "llvm/IR/Operator.h"
41 #include "llvm/IR/Type.h"
42 #include "llvm/IR/Value.h"
43 #include "llvm/Support/Casting.h"
45 #include "llvm/Support/KnownBits.h"
47 #include <cassert>
48 #include <cerrno>
49 #include <cfenv>
50 #include <cmath>
51 #include <cstddef>
52 #include <cstdint>
53 
54 using namespace llvm;
55 
56 namespace {
57 
58 //===----------------------------------------------------------------------===//
59 // Constant Folding internal helper functions
60 //===----------------------------------------------------------------------===//
61 
62 static Constant *foldConstVectorToAPInt(APInt &Result, Type *DestTy,
63  Constant *C, Type *SrcEltTy,
64  unsigned NumSrcElts,
65  const DataLayout &DL) {
66  // Now that we know that the input value is a vector of integers, just shift
67  // and insert them into our result.
68  unsigned BitShift = DL.getTypeSizeInBits(SrcEltTy);
69  for (unsigned i = 0; i != NumSrcElts; ++i) {
70  Constant *Element;
71  if (DL.isLittleEndian())
72  Element = C->getAggregateElement(NumSrcElts - i - 1);
73  else
74  Element = C->getAggregateElement(i);
75 
76  if (Element && isa<UndefValue>(Element)) {
77  Result <<= BitShift;
78  continue;
79  }
80 
81  auto *ElementCI = dyn_cast_or_null<ConstantInt>(Element);
82  if (!ElementCI)
83  return ConstantExpr::getBitCast(C, DestTy);
84 
85  Result <<= BitShift;
86  Result |= ElementCI->getValue().zextOrSelf(Result.getBitWidth());
87  }
88 
89  return nullptr;
90 }
91 
92 /// Constant fold bitcast, symbolically evaluating it with DataLayout.
93 /// This always returns a non-null constant, but it may be a
94 /// ConstantExpr if unfoldable.
95 Constant *FoldBitCast(Constant *C, Type *DestTy, const DataLayout &DL) {
96  // Catch the obvious splat cases.
97  if (C->isNullValue() && !DestTy->isX86_MMXTy())
98  return Constant::getNullValue(DestTy);
99  if (C->isAllOnesValue() && !DestTy->isX86_MMXTy() &&
100  !DestTy->isPtrOrPtrVectorTy()) // Don't get ones for ptr types!
101  return Constant::getAllOnesValue(DestTy);
102 
103  if (auto *VTy = dyn_cast<VectorType>(C->getType())) {
104  // Handle a vector->scalar integer/fp cast.
105  if (isa<IntegerType>(DestTy) || DestTy->isFloatingPointTy()) {
106  unsigned NumSrcElts = VTy->getNumElements();
107  Type *SrcEltTy = VTy->getElementType();
108 
109  // If the vector is a vector of floating point, convert it to vector of int
110  // to simplify things.
111  if (SrcEltTy->isFloatingPointTy()) {
112  unsigned FPWidth = SrcEltTy->getPrimitiveSizeInBits();
113  Type *SrcIVTy =
114  VectorType::get(IntegerType::get(C->getContext(), FPWidth), NumSrcElts);
115  // Ask IR to do the conversion now that #elts line up.
116  C = ConstantExpr::getBitCast(C, SrcIVTy);
117  }
118 
119  APInt Result(DL.getTypeSizeInBits(DestTy), 0);
120  if (Constant *CE = foldConstVectorToAPInt(Result, DestTy, C,
121  SrcEltTy, NumSrcElts, DL))
122  return CE;
123 
124  if (isa<IntegerType>(DestTy))
125  return ConstantInt::get(DestTy, Result);
126 
127  APFloat FP(DestTy->getFltSemantics(), Result);
128  return ConstantFP::get(DestTy->getContext(), FP);
129  }
130  }
131 
132  // The code below only handles casts to vectors currently.
133  auto *DestVTy = dyn_cast<VectorType>(DestTy);
134  if (!DestVTy)
135  return ConstantExpr::getBitCast(C, DestTy);
136 
137  // If this is a scalar -> vector cast, convert the input into a <1 x scalar>
138  // vector so the code below can handle it uniformly.
139  if (isa<ConstantFP>(C) || isa<ConstantInt>(C)) {
140  Constant *Ops = C; // don't take the address of C!
141  return FoldBitCast(ConstantVector::get(Ops), DestTy, DL);
142  }
143 
144  // If this is a bitcast from constant vector -> vector, fold it.
145  if (!isa<ConstantDataVector>(C) && !isa<ConstantVector>(C))
146  return ConstantExpr::getBitCast(C, DestTy);
147 
148  // If the element types match, IR can fold it.
149  unsigned NumDstElt = DestVTy->getNumElements();
150  unsigned NumSrcElt = C->getType()->getVectorNumElements();
151  if (NumDstElt == NumSrcElt)
152  return ConstantExpr::getBitCast(C, DestTy);
153 
154  Type *SrcEltTy = C->getType()->getVectorElementType();
155  Type *DstEltTy = DestVTy->getElementType();
156 
157  // Otherwise, we're changing the number of elements in a vector, which
158  // requires endianness information to do the right thing. For example,
159  // bitcast (<2 x i64> <i64 0, i64 1> to <4 x i32>)
160  // folds to (little endian):
161  // <4 x i32> <i32 0, i32 0, i32 1, i32 0>
162  // and to (big endian):
163  // <4 x i32> <i32 0, i32 0, i32 0, i32 1>
164 
165  // First thing is first. We only want to think about integer here, so if
166  // we have something in FP form, recast it as integer.
167  if (DstEltTy->isFloatingPointTy()) {
168  // Fold to an vector of integers with same size as our FP type.
169  unsigned FPWidth = DstEltTy->getPrimitiveSizeInBits();
170  Type *DestIVTy =
171  VectorType::get(IntegerType::get(C->getContext(), FPWidth), NumDstElt);
172  // Recursively handle this integer conversion, if possible.
173  C = FoldBitCast(C, DestIVTy, DL);
174 
175  // Finally, IR can handle this now that #elts line up.
176  return ConstantExpr::getBitCast(C, DestTy);
177  }
178 
179  // Okay, we know the destination is integer, if the input is FP, convert
180  // it to integer first.
181  if (SrcEltTy->isFloatingPointTy()) {
182  unsigned FPWidth = SrcEltTy->getPrimitiveSizeInBits();
183  Type *SrcIVTy =
184  VectorType::get(IntegerType::get(C->getContext(), FPWidth), NumSrcElt);
185  // Ask IR to do the conversion now that #elts line up.
186  C = ConstantExpr::getBitCast(C, SrcIVTy);
187  // If IR wasn't able to fold it, bail out.
188  if (!isa<ConstantVector>(C) && // FIXME: Remove ConstantVector.
189  !isa<ConstantDataVector>(C))
190  return C;
191  }
192 
193  // Now we know that the input and output vectors are both integer vectors
194  // of the same size, and that their #elements is not the same. Do the
195  // conversion here, which depends on whether the input or output has
196  // more elements.
197  bool isLittleEndian = DL.isLittleEndian();
198 
200  if (NumDstElt < NumSrcElt) {
201  // Handle: bitcast (<4 x i32> <i32 0, i32 1, i32 2, i32 3> to <2 x i64>)
202  Constant *Zero = Constant::getNullValue(DstEltTy);
203  unsigned Ratio = NumSrcElt/NumDstElt;
204  unsigned SrcBitSize = SrcEltTy->getPrimitiveSizeInBits();
205  unsigned SrcElt = 0;
206  for (unsigned i = 0; i != NumDstElt; ++i) {
207  // Build each element of the result.
208  Constant *Elt = Zero;
209  unsigned ShiftAmt = isLittleEndian ? 0 : SrcBitSize*(Ratio-1);
210  for (unsigned j = 0; j != Ratio; ++j) {
211  Constant *Src = C->getAggregateElement(SrcElt++);
212  if (Src && isa<UndefValue>(Src))
214  else
215  Src = dyn_cast_or_null<ConstantInt>(Src);
216  if (!Src) // Reject constantexpr elements.
217  return ConstantExpr::getBitCast(C, DestTy);
218 
219  // Zero extend the element to the right size.
220  Src = ConstantExpr::getZExt(Src, Elt->getType());
221 
222  // Shift it to the right place, depending on endianness.
223  Src = ConstantExpr::getShl(Src,
224  ConstantInt::get(Src->getType(), ShiftAmt));
225  ShiftAmt += isLittleEndian ? SrcBitSize : -SrcBitSize;
226 
227  // Mix it in.
228  Elt = ConstantExpr::getOr(Elt, Src);
229  }
230  Result.push_back(Elt);
231  }
232  return ConstantVector::get(Result);
233  }
234 
235  // Handle: bitcast (<2 x i64> <i64 0, i64 1> to <4 x i32>)
236  unsigned Ratio = NumDstElt/NumSrcElt;
237  unsigned DstBitSize = DL.getTypeSizeInBits(DstEltTy);
238 
239  // Loop over each source value, expanding into multiple results.
240  for (unsigned i = 0; i != NumSrcElt; ++i) {
241  auto *Element = C->getAggregateElement(i);
242 
243  if (!Element) // Reject constantexpr elements.
244  return ConstantExpr::getBitCast(C, DestTy);
245 
246  if (isa<UndefValue>(Element)) {
247  // Correctly Propagate undef values.
248  Result.append(Ratio, UndefValue::get(DstEltTy));
249  continue;
250  }
251 
252  auto *Src = dyn_cast<ConstantInt>(Element);
253  if (!Src)
254  return ConstantExpr::getBitCast(C, DestTy);
255 
256  unsigned ShiftAmt = isLittleEndian ? 0 : DstBitSize*(Ratio-1);
257  for (unsigned j = 0; j != Ratio; ++j) {
258  // Shift the piece of the value into the right place, depending on
259  // endianness.
260  Constant *Elt = ConstantExpr::getLShr(Src,
261  ConstantInt::get(Src->getType(), ShiftAmt));
262  ShiftAmt += isLittleEndian ? DstBitSize : -DstBitSize;
263 
264  // Truncate the element to an integer with the same pointer size and
265  // convert the element back to a pointer using a inttoptr.
266  if (DstEltTy->isPointerTy()) {
267  IntegerType *DstIntTy = Type::getIntNTy(C->getContext(), DstBitSize);
268  Constant *CE = ConstantExpr::getTrunc(Elt, DstIntTy);
269  Result.push_back(ConstantExpr::getIntToPtr(CE, DstEltTy));
270  continue;
271  }
272 
273  // Truncate and remember this piece.
274  Result.push_back(ConstantExpr::getTrunc(Elt, DstEltTy));
275  }
276  }
277 
278  return ConstantVector::get(Result);
279 }
280 
281 } // end anonymous namespace
282 
283 /// If this constant is a constant offset from a global, return the global and
284 /// the constant. Because of constantexprs, this function is recursive.
286  APInt &Offset, const DataLayout &DL) {
287  // Trivial case, constant is the global.
288  if ((GV = dyn_cast<GlobalValue>(C))) {
289  unsigned BitWidth = DL.getIndexTypeSizeInBits(GV->getType());
290  Offset = APInt(BitWidth, 0);
291  return true;
292  }
293 
294  // Otherwise, if this isn't a constant expr, bail out.
295  auto *CE = dyn_cast<ConstantExpr>(C);
296  if (!CE) return false;
297 
298  // Look through ptr->int and ptr->ptr casts.
299  if (CE->getOpcode() == Instruction::PtrToInt ||
300  CE->getOpcode() == Instruction::BitCast)
301  return IsConstantOffsetFromGlobal(CE->getOperand(0), GV, Offset, DL);
302 
303  // i32* getelementptr ([5 x i32]* @a, i32 0, i32 5)
304  auto *GEP = dyn_cast<GEPOperator>(CE);
305  if (!GEP)
306  return false;
307 
308  unsigned BitWidth = DL.getIndexTypeSizeInBits(GEP->getType());
309  APInt TmpOffset(BitWidth, 0);
310 
311  // If the base isn't a global+constant, we aren't either.
312  if (!IsConstantOffsetFromGlobal(CE->getOperand(0), GV, TmpOffset, DL))
313  return false;
314 
315  // Otherwise, add any offset that our operands provide.
316  if (!GEP->accumulateConstantOffset(DL, TmpOffset))
317  return false;
318 
319  Offset = TmpOffset;
320  return true;
321 }
322 
324  const DataLayout &DL) {
325  do {
326  Type *SrcTy = C->getType();
327 
328  // If the type sizes are the same and a cast is legal, just directly
329  // cast the constant.
330  if (DL.getTypeSizeInBits(DestTy) == DL.getTypeSizeInBits(SrcTy)) {
331  Instruction::CastOps Cast = Instruction::BitCast;
332  // If we are going from a pointer to int or vice versa, we spell the cast
333  // differently.
334  if (SrcTy->isIntegerTy() && DestTy->isPointerTy())
335  Cast = Instruction::IntToPtr;
336  else if (SrcTy->isPointerTy() && DestTy->isIntegerTy())
337  Cast = Instruction::PtrToInt;
338 
339  if (CastInst::castIsValid(Cast, C, DestTy))
340  return ConstantExpr::getCast(Cast, C, DestTy);
341  }
342 
343  // If this isn't an aggregate type, there is nothing we can do to drill down
344  // and find a bitcastable constant.
345  if (!SrcTy->isAggregateType())
346  return nullptr;
347 
348  // We're simulating a load through a pointer that was bitcast to point to
349  // a different type, so we can try to walk down through the initial
350  // elements of an aggregate to see if some part of the aggregate is
351  // castable to implement the "load" semantic model.
352  if (SrcTy->isStructTy()) {
353  // Struct types might have leading zero-length elements like [0 x i32],
354  // which are certainly not what we are looking for, so skip them.
355  unsigned Elem = 0;
356  Constant *ElemC;
357  do {
358  ElemC = C->getAggregateElement(Elem++);
359  } while (ElemC && DL.getTypeSizeInBits(ElemC->getType()) == 0);
360  C = ElemC;
361  } else {
362  C = C->getAggregateElement(0u);
363  }
364  } while (C);
365 
366  return nullptr;
367 }
368 
369 namespace {
370 
371 /// Recursive helper to read bits out of global. C is the constant being copied
372 /// out of. ByteOffset is an offset into C. CurPtr is the pointer to copy
373 /// results into and BytesLeft is the number of bytes left in
374 /// the CurPtr buffer. DL is the DataLayout.
375 bool ReadDataFromGlobal(Constant *C, uint64_t ByteOffset, unsigned char *CurPtr,
376  unsigned BytesLeft, const DataLayout &DL) {
377  assert(ByteOffset <= DL.getTypeAllocSize(C->getType()) &&
378  "Out of range access");
379 
380  // If this element is zero or undefined, we can just return since *CurPtr is
381  // zero initialized.
382  if (isa<ConstantAggregateZero>(C) || isa<UndefValue>(C))
383  return true;
384 
385  if (auto *CI = dyn_cast<ConstantInt>(C)) {
386  if (CI->getBitWidth() > 64 ||
387  (CI->getBitWidth() & 7) != 0)
388  return false;
389 
390  uint64_t Val = CI->getZExtValue();
391  unsigned IntBytes = unsigned(CI->getBitWidth()/8);
392 
393  for (unsigned i = 0; i != BytesLeft && ByteOffset != IntBytes; ++i) {
394  int n = ByteOffset;
395  if (!DL.isLittleEndian())
396  n = IntBytes - n - 1;
397  CurPtr[i] = (unsigned char)(Val >> (n * 8));
398  ++ByteOffset;
399  }
400  return true;
401  }
402 
403  if (auto *CFP = dyn_cast<ConstantFP>(C)) {
404  if (CFP->getType()->isDoubleTy()) {
405  C = FoldBitCast(C, Type::getInt64Ty(C->getContext()), DL);
406  return ReadDataFromGlobal(C, ByteOffset, CurPtr, BytesLeft, DL);
407  }
408  if (CFP->getType()->isFloatTy()){
409  C = FoldBitCast(C, Type::getInt32Ty(C->getContext()), DL);
410  return ReadDataFromGlobal(C, ByteOffset, CurPtr, BytesLeft, DL);
411  }
412  if (CFP->getType()->isHalfTy()){
413  C = FoldBitCast(C, Type::getInt16Ty(C->getContext()), DL);
414  return ReadDataFromGlobal(C, ByteOffset, CurPtr, BytesLeft, DL);
415  }
416  return false;
417  }
418 
419  if (auto *CS = dyn_cast<ConstantStruct>(C)) {
420  const StructLayout *SL = DL.getStructLayout(CS->getType());
421  unsigned Index = SL->getElementContainingOffset(ByteOffset);
422  uint64_t CurEltOffset = SL->getElementOffset(Index);
423  ByteOffset -= CurEltOffset;
424 
425  while (true) {
426  // If the element access is to the element itself and not to tail padding,
427  // read the bytes from the element.
428  uint64_t EltSize = DL.getTypeAllocSize(CS->getOperand(Index)->getType());
429 
430  if (ByteOffset < EltSize &&
431  !ReadDataFromGlobal(CS->getOperand(Index), ByteOffset, CurPtr,
432  BytesLeft, DL))
433  return false;
434 
435  ++Index;
436 
437  // Check to see if we read from the last struct element, if so we're done.
438  if (Index == CS->getType()->getNumElements())
439  return true;
440 
441  // If we read all of the bytes we needed from this element we're done.
442  uint64_t NextEltOffset = SL->getElementOffset(Index);
443 
444  if (BytesLeft <= NextEltOffset - CurEltOffset - ByteOffset)
445  return true;
446 
447  // Move to the next element of the struct.
448  CurPtr += NextEltOffset - CurEltOffset - ByteOffset;
449  BytesLeft -= NextEltOffset - CurEltOffset - ByteOffset;
450  ByteOffset = 0;
451  CurEltOffset = NextEltOffset;
452  }
453  // not reached.
454  }
455 
456  if (isa<ConstantArray>(C) || isa<ConstantVector>(C) ||
457  isa<ConstantDataSequential>(C)) {
458  Type *EltTy = C->getType()->getSequentialElementType();
459  uint64_t EltSize = DL.getTypeAllocSize(EltTy);
460  uint64_t Index = ByteOffset / EltSize;
461  uint64_t Offset = ByteOffset - Index * EltSize;
462  uint64_t NumElts;
463  if (auto *AT = dyn_cast<ArrayType>(C->getType()))
464  NumElts = AT->getNumElements();
465  else
466  NumElts = C->getType()->getVectorNumElements();
467 
468  for (; Index != NumElts; ++Index) {
469  if (!ReadDataFromGlobal(C->getAggregateElement(Index), Offset, CurPtr,
470  BytesLeft, DL))
471  return false;
472 
473  uint64_t BytesWritten = EltSize - Offset;
474  assert(BytesWritten <= EltSize && "Not indexing into this element?");
475  if (BytesWritten >= BytesLeft)
476  return true;
477 
478  Offset = 0;
479  BytesLeft -= BytesWritten;
480  CurPtr += BytesWritten;
481  }
482  return true;
483  }
484 
485  if (auto *CE = dyn_cast<ConstantExpr>(C)) {
486  if (CE->getOpcode() == Instruction::IntToPtr &&
487  CE->getOperand(0)->getType() == DL.getIntPtrType(CE->getType())) {
488  return ReadDataFromGlobal(CE->getOperand(0), ByteOffset, CurPtr,
489  BytesLeft, DL);
490  }
491  }
492 
493  // Otherwise, unknown initializer type.
494  return false;
495 }
496 
497 Constant *FoldReinterpretLoadFromConstPtr(Constant *C, Type *LoadTy,
498  const DataLayout &DL) {
499  auto *PTy = cast<PointerType>(C->getType());
500  auto *IntType = dyn_cast<IntegerType>(LoadTy);
501 
502  // If this isn't an integer load we can't fold it directly.
503  if (!IntType) {
504  unsigned AS = PTy->getAddressSpace();
505 
506  // If this is a float/double load, we can try folding it as an int32/64 load
507  // and then bitcast the result. This can be useful for union cases. Note
508  // that address spaces don't matter here since we're not going to result in
509  // an actual new load.
510  Type *MapTy;
511  if (LoadTy->isHalfTy())
512  MapTy = Type::getInt16Ty(C->getContext());
513  else if (LoadTy->isFloatTy())
514  MapTy = Type::getInt32Ty(C->getContext());
515  else if (LoadTy->isDoubleTy())
516  MapTy = Type::getInt64Ty(C->getContext());
517  else if (LoadTy->isVectorTy()) {
518  MapTy = PointerType::getIntNTy(C->getContext(),
519  DL.getTypeSizeInBits(LoadTy));
520  } else
521  return nullptr;
522 
523  C = FoldBitCast(C, MapTy->getPointerTo(AS), DL);
524  if (Constant *Res = FoldReinterpretLoadFromConstPtr(C, MapTy, DL))
525  return FoldBitCast(Res, LoadTy, DL);
526  return nullptr;
527  }
528 
529  unsigned BytesLoaded = (IntType->getBitWidth() + 7) / 8;
530  if (BytesLoaded > 32 || BytesLoaded == 0)
531  return nullptr;
532 
533  GlobalValue *GVal;
534  APInt OffsetAI;
535  if (!IsConstantOffsetFromGlobal(C, GVal, OffsetAI, DL))
536  return nullptr;
537 
538  auto *GV = dyn_cast<GlobalVariable>(GVal);
539  if (!GV || !GV->isConstant() || !GV->hasDefinitiveInitializer() ||
540  !GV->getInitializer()->getType()->isSized())
541  return nullptr;
542 
543  int64_t Offset = OffsetAI.getSExtValue();
544  int64_t InitializerSize = DL.getTypeAllocSize(GV->getInitializer()->getType());
545 
546  // If we're not accessing anything in this constant, the result is undefined.
547  if (Offset <= -1 * static_cast<int64_t>(BytesLoaded))
548  return UndefValue::get(IntType);
549 
550  // If we're not accessing anything in this constant, the result is undefined.
551  if (Offset >= InitializerSize)
552  return UndefValue::get(IntType);
553 
554  unsigned char RawBytes[32] = {0};
555  unsigned char *CurPtr = RawBytes;
556  unsigned BytesLeft = BytesLoaded;
557 
558  // If we're loading off the beginning of the global, some bytes may be valid.
559  if (Offset < 0) {
560  CurPtr += -Offset;
561  BytesLeft += Offset;
562  Offset = 0;
563  }
564 
565  if (!ReadDataFromGlobal(GV->getInitializer(), Offset, CurPtr, BytesLeft, DL))
566  return nullptr;
567 
568  APInt ResultVal = APInt(IntType->getBitWidth(), 0);
569  if (DL.isLittleEndian()) {
570  ResultVal = RawBytes[BytesLoaded - 1];
571  for (unsigned i = 1; i != BytesLoaded; ++i) {
572  ResultVal <<= 8;
573  ResultVal |= RawBytes[BytesLoaded - 1 - i];
574  }
575  } else {
576  ResultVal = RawBytes[0];
577  for (unsigned i = 1; i != BytesLoaded; ++i) {
578  ResultVal <<= 8;
579  ResultVal |= RawBytes[i];
580  }
581  }
582 
583  return ConstantInt::get(IntType->getContext(), ResultVal);
584 }
585 
586 Constant *ConstantFoldLoadThroughBitcastExpr(ConstantExpr *CE, Type *DestTy,
587  const DataLayout &DL) {
588  auto *SrcPtr = CE->getOperand(0);
589  auto *SrcPtrTy = dyn_cast<PointerType>(SrcPtr->getType());
590  if (!SrcPtrTy)
591  return nullptr;
592  Type *SrcTy = SrcPtrTy->getPointerElementType();
593 
594  Constant *C = ConstantFoldLoadFromConstPtr(SrcPtr, SrcTy, DL);
595  if (!C)
596  return nullptr;
597 
598  return llvm::ConstantFoldLoadThroughBitcast(C, DestTy, DL);
599 }
600 
601 } // end anonymous namespace
602 
604  const DataLayout &DL) {
605  // First, try the easy cases:
606  if (auto *GV = dyn_cast<GlobalVariable>(C))
607  if (GV->isConstant() && GV->hasDefinitiveInitializer())
608  return GV->getInitializer();
609 
610  if (auto *GA = dyn_cast<GlobalAlias>(C))
611  if (GA->getAliasee() && !GA->isInterposable())
612  return ConstantFoldLoadFromConstPtr(GA->getAliasee(), Ty, DL);
613 
614  // If the loaded value isn't a constant expr, we can't handle it.
615  auto *CE = dyn_cast<ConstantExpr>(C);
616  if (!CE)
617  return nullptr;
618 
619  if (CE->getOpcode() == Instruction::GetElementPtr) {
620  if (auto *GV = dyn_cast<GlobalVariable>(CE->getOperand(0))) {
621  if (GV->isConstant() && GV->hasDefinitiveInitializer()) {
622  if (Constant *V =
623  ConstantFoldLoadThroughGEPConstantExpr(GV->getInitializer(), CE))
624  return V;
625  }
626  }
627  }
628 
629  if (CE->getOpcode() == Instruction::BitCast)
630  if (Constant *LoadedC = ConstantFoldLoadThroughBitcastExpr(CE, Ty, DL))
631  return LoadedC;
632 
633  // Instead of loading constant c string, use corresponding integer value
634  // directly if string length is small enough.
635  StringRef Str;
636  if (getConstantStringInfo(CE, Str) && !Str.empty()) {
637  size_t StrLen = Str.size();
638  unsigned NumBits = Ty->getPrimitiveSizeInBits();
639  // Replace load with immediate integer if the result is an integer or fp
640  // value.
641  if ((NumBits >> 3) == StrLen + 1 && (NumBits & 7) == 0 &&
642  (isa<IntegerType>(Ty) || Ty->isFloatingPointTy())) {
643  APInt StrVal(NumBits, 0);
644  APInt SingleChar(NumBits, 0);
645  if (DL.isLittleEndian()) {
646  for (unsigned char C : reverse(Str.bytes())) {
647  SingleChar = static_cast<uint64_t>(C);
648  StrVal = (StrVal << 8) | SingleChar;
649  }
650  } else {
651  for (unsigned char C : Str.bytes()) {
652  SingleChar = static_cast<uint64_t>(C);
653  StrVal = (StrVal << 8) | SingleChar;
654  }
655  // Append NULL at the end.
656  SingleChar = 0;
657  StrVal = (StrVal << 8) | SingleChar;
658  }
659 
660  Constant *Res = ConstantInt::get(CE->getContext(), StrVal);
661  if (Ty->isFloatingPointTy())
662  Res = ConstantExpr::getBitCast(Res, Ty);
663  return Res;
664  }
665  }
666 
667  // If this load comes from anywhere in a constant global, and if the global
668  // is all undef or zero, we know what it loads.
669  if (auto *GV = dyn_cast<GlobalVariable>(GetUnderlyingObject(CE, DL))) {
670  if (GV->isConstant() && GV->hasDefinitiveInitializer()) {
671  if (GV->getInitializer()->isNullValue())
672  return Constant::getNullValue(Ty);
673  if (isa<UndefValue>(GV->getInitializer()))
674  return UndefValue::get(Ty);
675  }
676  }
677 
678  // Try hard to fold loads from bitcasted strange and non-type-safe things.
679  return FoldReinterpretLoadFromConstPtr(CE, Ty, DL);
680 }
681 
682 namespace {
683 
684 Constant *ConstantFoldLoadInst(const LoadInst *LI, const DataLayout &DL) {
685  if (LI->isVolatile()) return nullptr;
686 
687  if (auto *C = dyn_cast<Constant>(LI->getOperand(0)))
688  return ConstantFoldLoadFromConstPtr(C, LI->getType(), DL);
689 
690  return nullptr;
691 }
692 
693 /// One of Op0/Op1 is a constant expression.
694 /// Attempt to symbolically evaluate the result of a binary operator merging
695 /// these together. If target data info is available, it is provided as DL,
696 /// otherwise DL is null.
697 Constant *SymbolicallyEvaluateBinop(unsigned Opc, Constant *Op0, Constant *Op1,
698  const DataLayout &DL) {
699  // SROA
700 
701  // Fold (and 0xffffffff00000000, (shl x, 32)) -> shl.
702  // Fold (lshr (or X, Y), 32) -> (lshr [X/Y], 32) if one doesn't contribute
703  // bits.
704 
705  if (Opc == Instruction::And) {
706  KnownBits Known0 = computeKnownBits(Op0, DL);
707  KnownBits Known1 = computeKnownBits(Op1, DL);
708  if ((Known1.One | Known0.Zero).isAllOnesValue()) {
709  // All the bits of Op0 that the 'and' could be masking are already zero.
710  return Op0;
711  }
712  if ((Known0.One | Known1.Zero).isAllOnesValue()) {
713  // All the bits of Op1 that the 'and' could be masking are already zero.
714  return Op1;
715  }
716 
717  Known0.Zero |= Known1.Zero;
718  Known0.One &= Known1.One;
719  if (Known0.isConstant())
720  return ConstantInt::get(Op0->getType(), Known0.getConstant());
721  }
722 
723  // If the constant expr is something like &A[123] - &A[4].f, fold this into a
724  // constant. This happens frequently when iterating over a global array.
725  if (Opc == Instruction::Sub) {
726  GlobalValue *GV1, *GV2;
727  APInt Offs1, Offs2;
728 
729  if (IsConstantOffsetFromGlobal(Op0, GV1, Offs1, DL))
730  if (IsConstantOffsetFromGlobal(Op1, GV2, Offs2, DL) && GV1 == GV2) {
731  unsigned OpSize = DL.getTypeSizeInBits(Op0->getType());
732 
733  // (&GV+C1) - (&GV+C2) -> C1-C2, pointer arithmetic cannot overflow.
734  // PtrToInt may change the bitwidth so we have convert to the right size
735  // first.
736  return ConstantInt::get(Op0->getType(), Offs1.zextOrTrunc(OpSize) -
737  Offs2.zextOrTrunc(OpSize));
738  }
739  }
740 
741  return nullptr;
742 }
743 
744 /// If array indices are not pointer-sized integers, explicitly cast them so
745 /// that they aren't implicitly casted by the getelementptr.
746 Constant *CastGEPIndices(Type *SrcElemTy, ArrayRef<Constant *> Ops,
747  Type *ResultTy, Optional<unsigned> InRangeIndex,
748  const DataLayout &DL, const TargetLibraryInfo *TLI) {
749  Type *IntPtrTy = DL.getIntPtrType(ResultTy);
750  Type *IntPtrScalarTy = IntPtrTy->getScalarType();
751 
752  bool Any = false;
754  for (unsigned i = 1, e = Ops.size(); i != e; ++i) {
755  if ((i == 1 ||
756  !isa<StructType>(GetElementPtrInst::getIndexedType(
757  SrcElemTy, Ops.slice(1, i - 1)))) &&
758  Ops[i]->getType()->getScalarType() != IntPtrScalarTy) {
759  Any = true;
760  Type *NewType = Ops[i]->getType()->isVectorTy()
761  ? IntPtrTy
762  : IntPtrTy->getScalarType();
764  true,
765  NewType,
766  true),
767  Ops[i], NewType));
768  } else
769  NewIdxs.push_back(Ops[i]);
770  }
771 
772  if (!Any)
773  return nullptr;
774 
776  SrcElemTy, Ops[0], NewIdxs, /*InBounds=*/false, InRangeIndex);
777  if (Constant *Folded = ConstantFoldConstant(C, DL, TLI))
778  C = Folded;
779 
780  return C;
781 }
782 
783 /// Strip the pointer casts, but preserve the address space information.
784 Constant *StripPtrCastKeepAS(Constant *Ptr, Type *&ElemTy) {
785  assert(Ptr->getType()->isPointerTy() && "Not a pointer type");
786  auto *OldPtrTy = cast<PointerType>(Ptr->getType());
787  Ptr = cast<Constant>(Ptr->stripPointerCasts());
788  auto *NewPtrTy = cast<PointerType>(Ptr->getType());
789 
790  ElemTy = NewPtrTy->getPointerElementType();
791 
792  // Preserve the address space number of the pointer.
793  if (NewPtrTy->getAddressSpace() != OldPtrTy->getAddressSpace()) {
794  NewPtrTy = ElemTy->getPointerTo(OldPtrTy->getAddressSpace());
795  Ptr = ConstantExpr::getPointerCast(Ptr, NewPtrTy);
796  }
797  return Ptr;
798 }
799 
800 /// If we can symbolically evaluate the GEP constant expression, do so.
801 Constant *SymbolicallyEvaluateGEP(const GEPOperator *GEP,
803  const DataLayout &DL,
804  const TargetLibraryInfo *TLI) {
805  const GEPOperator *InnermostGEP = GEP;
806  bool InBounds = GEP->isInBounds();
807 
808  Type *SrcElemTy = GEP->getSourceElementType();
809  Type *ResElemTy = GEP->getResultElementType();
810  Type *ResTy = GEP->getType();
811  if (!SrcElemTy->isSized())
812  return nullptr;
813 
814  if (Constant *C = CastGEPIndices(SrcElemTy, Ops, ResTy,
815  GEP->getInRangeIndex(), DL, TLI))
816  return C;
817 
818  Constant *Ptr = Ops[0];
819  if (!Ptr->getType()->isPointerTy())
820  return nullptr;
821 
822  Type *IntPtrTy = DL.getIntPtrType(Ptr->getType());
823 
824  // If this is a constant expr gep that is effectively computing an
825  // "offsetof", fold it into 'cast int Size to T*' instead of 'gep 0, 0, 12'
826  for (unsigned i = 1, e = Ops.size(); i != e; ++i)
827  if (!isa<ConstantInt>(Ops[i])) {
828 
829  // If this is "gep i8* Ptr, (sub 0, V)", fold this as:
830  // "inttoptr (sub (ptrtoint Ptr), V)"
831  if (Ops.size() == 2 && ResElemTy->isIntegerTy(8)) {
832  auto *CE = dyn_cast<ConstantExpr>(Ops[1]);
833  assert((!CE || CE->getType() == IntPtrTy) &&
834  "CastGEPIndices didn't canonicalize index types!");
835  if (CE && CE->getOpcode() == Instruction::Sub &&
836  CE->getOperand(0)->isNullValue()) {
837  Constant *Res = ConstantExpr::getPtrToInt(Ptr, CE->getType());
838  Res = ConstantExpr::getSub(Res, CE->getOperand(1));
839  Res = ConstantExpr::getIntToPtr(Res, ResTy);
840  if (auto *FoldedRes = ConstantFoldConstant(Res, DL, TLI))
841  Res = FoldedRes;
842  return Res;
843  }
844  }
845  return nullptr;
846  }
847 
848  unsigned BitWidth = DL.getTypeSizeInBits(IntPtrTy);
849  APInt Offset =
850  APInt(BitWidth,
852  SrcElemTy,
853  makeArrayRef((Value * const *)Ops.data() + 1, Ops.size() - 1)));
854  Ptr = StripPtrCastKeepAS(Ptr, SrcElemTy);
855 
856  // If this is a GEP of a GEP, fold it all into a single GEP.
857  while (auto *GEP = dyn_cast<GEPOperator>(Ptr)) {
858  InnermostGEP = GEP;
859  InBounds &= GEP->isInBounds();
860 
861  SmallVector<Value *, 4> NestedOps(GEP->op_begin() + 1, GEP->op_end());
862 
863  // Do not try the incorporate the sub-GEP if some index is not a number.
864  bool AllConstantInt = true;
865  for (Value *NestedOp : NestedOps)
866  if (!isa<ConstantInt>(NestedOp)) {
867  AllConstantInt = false;
868  break;
869  }
870  if (!AllConstantInt)
871  break;
872 
873  Ptr = cast<Constant>(GEP->getOperand(0));
874  SrcElemTy = GEP->getSourceElementType();
875  Offset += APInt(BitWidth, DL.getIndexedOffsetInType(SrcElemTy, NestedOps));
876  Ptr = StripPtrCastKeepAS(Ptr, SrcElemTy);
877  }
878 
879  // If the base value for this address is a literal integer value, fold the
880  // getelementptr to the resulting integer value casted to the pointer type.
881  APInt BasePtr(BitWidth, 0);
882  if (auto *CE = dyn_cast<ConstantExpr>(Ptr)) {
883  if (CE->getOpcode() == Instruction::IntToPtr) {
884  if (auto *Base = dyn_cast<ConstantInt>(CE->getOperand(0)))
885  BasePtr = Base->getValue().zextOrTrunc(BitWidth);
886  }
887  }
888 
889  auto *PTy = cast<PointerType>(Ptr->getType());
890  if ((Ptr->isNullValue() || BasePtr != 0) &&
891  !DL.isNonIntegralPointerType(PTy)) {
892  Constant *C = ConstantInt::get(Ptr->getContext(), Offset + BasePtr);
893  return ConstantExpr::getIntToPtr(C, ResTy);
894  }
895 
896  // Otherwise form a regular getelementptr. Recompute the indices so that
897  // we eliminate over-indexing of the notional static type array bounds.
898  // This makes it easy to determine if the getelementptr is "inbounds".
899  // Also, this helps GlobalOpt do SROA on GlobalVariables.
900  Type *Ty = PTy;
902 
903  do {
904  if (!Ty->isStructTy()) {
905  if (Ty->isPointerTy()) {
906  // The only pointer indexing we'll do is on the first index of the GEP.
907  if (!NewIdxs.empty())
908  break;
909 
910  Ty = SrcElemTy;
911 
912  // Only handle pointers to sized types, not pointers to functions.
913  if (!Ty->isSized())
914  return nullptr;
915  } else if (auto *ATy = dyn_cast<SequentialType>(Ty)) {
916  Ty = ATy->getElementType();
917  } else {
918  // We've reached some non-indexable type.
919  break;
920  }
921 
922  // Determine which element of the array the offset points into.
923  APInt ElemSize(BitWidth, DL.getTypeAllocSize(Ty));
924  if (ElemSize == 0) {
925  // The element size is 0. This may be [0 x Ty]*, so just use a zero
926  // index for this level and proceed to the next level to see if it can
927  // accommodate the offset.
928  NewIdxs.push_back(ConstantInt::get(IntPtrTy, 0));
929  } else {
930  // The element size is non-zero divide the offset by the element
931  // size (rounding down), to compute the index at this level.
932  bool Overflow;
933  APInt NewIdx = Offset.sdiv_ov(ElemSize, Overflow);
934  if (Overflow)
935  break;
936  Offset -= NewIdx * ElemSize;
937  NewIdxs.push_back(ConstantInt::get(IntPtrTy, NewIdx));
938  }
939  } else {
940  auto *STy = cast<StructType>(Ty);
941  // If we end up with an offset that isn't valid for this struct type, we
942  // can't re-form this GEP in a regular form, so bail out. The pointer
943  // operand likely went through casts that are necessary to make the GEP
944  // sensible.
945  const StructLayout &SL = *DL.getStructLayout(STy);
946  if (Offset.isNegative() || Offset.uge(SL.getSizeInBytes()))
947  break;
948 
949  // Determine which field of the struct the offset points into. The
950  // getZExtValue is fine as we've already ensured that the offset is
951  // within the range representable by the StructLayout API.
952  unsigned ElIdx = SL.getElementContainingOffset(Offset.getZExtValue());
954  ElIdx));
955  Offset -= APInt(BitWidth, SL.getElementOffset(ElIdx));
956  Ty = STy->getTypeAtIndex(ElIdx);
957  }
958  } while (Ty != ResElemTy);
959 
960  // If we haven't used up the entire offset by descending the static
961  // type, then the offset is pointing into the middle of an indivisible
962  // member, so we can't simplify it.
963  if (Offset != 0)
964  return nullptr;
965 
966  // Preserve the inrange index from the innermost GEP if possible. We must
967  // have calculated the same indices up to and including the inrange index.
968  Optional<unsigned> InRangeIndex;
969  if (Optional<unsigned> LastIRIndex = InnermostGEP->getInRangeIndex())
970  if (SrcElemTy == InnermostGEP->getSourceElementType() &&
971  NewIdxs.size() > *LastIRIndex) {
972  InRangeIndex = LastIRIndex;
973  for (unsigned I = 0; I <= *LastIRIndex; ++I)
974  if (NewIdxs[I] != InnermostGEP->getOperand(I + 1))
975  return nullptr;
976  }
977 
978  // Create a GEP.
979  Constant *C = ConstantExpr::getGetElementPtr(SrcElemTy, Ptr, NewIdxs,
980  InBounds, InRangeIndex);
981  assert(C->getType()->getPointerElementType() == Ty &&
982  "Computed GetElementPtr has unexpected type!");
983 
984  // If we ended up indexing a member with a type that doesn't match
985  // the type of what the original indices indexed, add a cast.
986  if (Ty != ResElemTy)
987  C = FoldBitCast(C, ResTy, DL);
988 
989  return C;
990 }
991 
992 /// Attempt to constant fold an instruction with the
993 /// specified opcode and operands. If successful, the constant result is
994 /// returned, if not, null is returned. Note that this function can fail when
995 /// attempting to fold instructions like loads and stores, which have no
996 /// constant expression form.
997 Constant *ConstantFoldInstOperandsImpl(const Value *InstOrCE, unsigned Opcode,
999  const DataLayout &DL,
1000  const TargetLibraryInfo *TLI) {
1001  Type *DestTy = InstOrCE->getType();
1002 
1003  if (Instruction::isUnaryOp(Opcode))
1004  return ConstantFoldUnaryOpOperand(Opcode, Ops[0], DL);
1005 
1006  if (Instruction::isBinaryOp(Opcode))
1007  return ConstantFoldBinaryOpOperands(Opcode, Ops[0], Ops[1], DL);
1008 
1009  if (Instruction::isCast(Opcode))
1010  return ConstantFoldCastOperand(Opcode, Ops[0], DestTy, DL);
1011 
1012  if (auto *GEP = dyn_cast<GEPOperator>(InstOrCE)) {
1013  if (Constant *C = SymbolicallyEvaluateGEP(GEP, Ops, DL, TLI))
1014  return C;
1015 
1017  Ops.slice(1), GEP->isInBounds(),
1018  GEP->getInRangeIndex());
1019  }
1020 
1021  if (auto *CE = dyn_cast<ConstantExpr>(InstOrCE))
1022  return CE->getWithOperands(Ops);
1023 
1024  switch (Opcode) {
1025  default: return nullptr;
1026  case Instruction::ICmp:
1027  case Instruction::FCmp: llvm_unreachable("Invalid for compares");
1028  case Instruction::Call:
1029  if (auto *F = dyn_cast<Function>(Ops.back())) {
1030  const auto *Call = cast<CallBase>(InstOrCE);
1031  if (canConstantFoldCallTo(Call, F))
1032  return ConstantFoldCall(Call, F, Ops.slice(0, Ops.size() - 1), TLI);
1033  }
1034  return nullptr;
1035  case Instruction::Select:
1036  return ConstantExpr::getSelect(Ops[0], Ops[1], Ops[2]);
1037  case Instruction::ExtractElement:
1038  return ConstantExpr::getExtractElement(Ops[0], Ops[1]);
1039  case Instruction::ExtractValue:
1041  Ops[0], dyn_cast<ExtractValueInst>(InstOrCE)->getIndices());
1042  case Instruction::InsertElement:
1043  return ConstantExpr::getInsertElement(Ops[0], Ops[1], Ops[2]);
1044  case Instruction::ShuffleVector:
1045  return ConstantExpr::getShuffleVector(Ops[0], Ops[1], Ops[2]);
1046  }
1047 }
1048 
1049 } // end anonymous namespace
1050 
1051 //===----------------------------------------------------------------------===//
1052 // Constant Folding public APIs
1053 //===----------------------------------------------------------------------===//
1054 
1055 namespace {
1056 
1057 Constant *
1058 ConstantFoldConstantImpl(const Constant *C, const DataLayout &DL,
1059  const TargetLibraryInfo *TLI,
1061  if (!isa<ConstantVector>(C) && !isa<ConstantExpr>(C))
1062  return nullptr;
1063 
1065  for (const Use &NewU : C->operands()) {
1066  auto *NewC = cast<Constant>(&NewU);
1067  // Recursively fold the ConstantExpr's operands. If we have already folded
1068  // a ConstantExpr, we don't have to process it again.
1069  if (isa<ConstantVector>(NewC) || isa<ConstantExpr>(NewC)) {
1070  auto It = FoldedOps.find(NewC);
1071  if (It == FoldedOps.end()) {
1072  if (auto *FoldedC =
1073  ConstantFoldConstantImpl(NewC, DL, TLI, FoldedOps)) {
1074  FoldedOps.insert({NewC, FoldedC});
1075  NewC = FoldedC;
1076  } else {
1077  FoldedOps.insert({NewC, NewC});
1078  }
1079  } else {
1080  NewC = It->second;
1081  }
1082  }
1083  Ops.push_back(NewC);
1084  }
1085 
1086  if (auto *CE = dyn_cast<ConstantExpr>(C)) {
1087  if (CE->isCompare())
1088  return ConstantFoldCompareInstOperands(CE->getPredicate(), Ops[0], Ops[1],
1089  DL, TLI);
1090 
1091  return ConstantFoldInstOperandsImpl(CE, CE->getOpcode(), Ops, DL, TLI);
1092  }
1093 
1094  assert(isa<ConstantVector>(C));
1095  return ConstantVector::get(Ops);
1096 }
1097 
1098 } // end anonymous namespace
1099 
1101  const TargetLibraryInfo *TLI) {
1102  // Handle PHI nodes quickly here...
1103  if (auto *PN = dyn_cast<PHINode>(I)) {
1104  Constant *CommonValue = nullptr;
1105 
1107  for (Value *Incoming : PN->incoming_values()) {
1108  // If the incoming value is undef then skip it. Note that while we could
1109  // skip the value if it is equal to the phi node itself we choose not to
1110  // because that would break the rule that constant folding only applies if
1111  // all operands are constants.
1112  if (isa<UndefValue>(Incoming))
1113  continue;
1114  // If the incoming value is not a constant, then give up.
1115  auto *C = dyn_cast<Constant>(Incoming);
1116  if (!C)
1117  return nullptr;
1118  // Fold the PHI's operands.
1119  if (auto *FoldedC = ConstantFoldConstantImpl(C, DL, TLI, FoldedOps))
1120  C = FoldedC;
1121  // If the incoming value is a different constant to
1122  // the one we saw previously, then give up.
1123  if (CommonValue && C != CommonValue)
1124  return nullptr;
1125  CommonValue = C;
1126  }
1127 
1128  // If we reach here, all incoming values are the same constant or undef.
1129  return CommonValue ? CommonValue : UndefValue::get(PN->getType());
1130  }
1131 
1132  // Scan the operand list, checking to see if they are all constants, if so,
1133  // hand off to ConstantFoldInstOperandsImpl.
1134  if (!all_of(I->operands(), [](Use &U) { return isa<Constant>(U); }))
1135  return nullptr;
1136 
1139  for (const Use &OpU : I->operands()) {
1140  auto *Op = cast<Constant>(&OpU);
1141  // Fold the Instruction's operands.
1142  if (auto *FoldedOp = ConstantFoldConstantImpl(Op, DL, TLI, FoldedOps))
1143  Op = FoldedOp;
1144 
1145  Ops.push_back(Op);
1146  }
1147 
1148  if (const auto *CI = dyn_cast<CmpInst>(I))
1149  return ConstantFoldCompareInstOperands(CI->getPredicate(), Ops[0], Ops[1],
1150  DL, TLI);
1151 
1152  if (const auto *LI = dyn_cast<LoadInst>(I))
1153  return ConstantFoldLoadInst(LI, DL);
1154 
1155  if (auto *IVI = dyn_cast<InsertValueInst>(I)) {
1157  cast<Constant>(IVI->getAggregateOperand()),
1158  cast<Constant>(IVI->getInsertedValueOperand()),
1159  IVI->getIndices());
1160  }
1161 
1162  if (auto *EVI = dyn_cast<ExtractValueInst>(I)) {
1164  cast<Constant>(EVI->getAggregateOperand()),
1165  EVI->getIndices());
1166  }
1167 
1168  return ConstantFoldInstOperands(I, Ops, DL, TLI);
1169 }
1170 
1172  const TargetLibraryInfo *TLI) {
1174  return ConstantFoldConstantImpl(C, DL, TLI, FoldedOps);
1175 }
1176 
1179  const DataLayout &DL,
1180  const TargetLibraryInfo *TLI) {
1181  return ConstantFoldInstOperandsImpl(I, I->getOpcode(), Ops, DL, TLI);
1182 }
1183 
1185  Constant *Ops0, Constant *Ops1,
1186  const DataLayout &DL,
1187  const TargetLibraryInfo *TLI) {
1188  // fold: icmp (inttoptr x), null -> icmp x, 0
1189  // fold: icmp null, (inttoptr x) -> icmp 0, x
1190  // fold: icmp (ptrtoint x), 0 -> icmp x, null
1191  // fold: icmp 0, (ptrtoint x) -> icmp null, x
1192  // fold: icmp (inttoptr x), (inttoptr y) -> icmp trunc/zext x, trunc/zext y
1193  // fold: icmp (ptrtoint x), (ptrtoint y) -> icmp x, y
1194  //
1195  // FIXME: The following comment is out of data and the DataLayout is here now.
1196  // ConstantExpr::getCompare cannot do this, because it doesn't have DL
1197  // around to know if bit truncation is happening.
1198  if (auto *CE0 = dyn_cast<ConstantExpr>(Ops0)) {
1199  if (Ops1->isNullValue()) {
1200  if (CE0->getOpcode() == Instruction::IntToPtr) {
1201  Type *IntPtrTy = DL.getIntPtrType(CE0->getType());
1202  // Convert the integer value to the right size to ensure we get the
1203  // proper extension or truncation.
1204  Constant *C = ConstantExpr::getIntegerCast(CE0->getOperand(0),
1205  IntPtrTy, false);
1206  Constant *Null = Constant::getNullValue(C->getType());
1207  return ConstantFoldCompareInstOperands(Predicate, C, Null, DL, TLI);
1208  }
1209 
1210  // Only do this transformation if the int is intptrty in size, otherwise
1211  // there is a truncation or extension that we aren't modeling.
1212  if (CE0->getOpcode() == Instruction::PtrToInt) {
1213  Type *IntPtrTy = DL.getIntPtrType(CE0->getOperand(0)->getType());
1214  if (CE0->getType() == IntPtrTy) {
1215  Constant *C = CE0->getOperand(0);
1216  Constant *Null = Constant::getNullValue(C->getType());
1217  return ConstantFoldCompareInstOperands(Predicate, C, Null, DL, TLI);
1218  }
1219  }
1220  }
1221 
1222  if (auto *CE1 = dyn_cast<ConstantExpr>(Ops1)) {
1223  if (CE0->getOpcode() == CE1->getOpcode()) {
1224  if (CE0->getOpcode() == Instruction::IntToPtr) {
1225  Type *IntPtrTy = DL.getIntPtrType(CE0->getType());
1226 
1227  // Convert the integer value to the right size to ensure we get the
1228  // proper extension or truncation.
1229  Constant *C0 = ConstantExpr::getIntegerCast(CE0->getOperand(0),
1230  IntPtrTy, false);
1231  Constant *C1 = ConstantExpr::getIntegerCast(CE1->getOperand(0),
1232  IntPtrTy, false);
1233  return ConstantFoldCompareInstOperands(Predicate, C0, C1, DL, TLI);
1234  }
1235 
1236  // Only do this transformation if the int is intptrty in size, otherwise
1237  // there is a truncation or extension that we aren't modeling.
1238  if (CE0->getOpcode() == Instruction::PtrToInt) {
1239  Type *IntPtrTy = DL.getIntPtrType(CE0->getOperand(0)->getType());
1240  if (CE0->getType() == IntPtrTy &&
1241  CE0->getOperand(0)->getType() == CE1->getOperand(0)->getType()) {
1243  Predicate, CE0->getOperand(0), CE1->getOperand(0), DL, TLI);
1244  }
1245  }
1246  }
1247  }
1248 
1249  // icmp eq (or x, y), 0 -> (icmp eq x, 0) & (icmp eq y, 0)
1250  // icmp ne (or x, y), 0 -> (icmp ne x, 0) | (icmp ne y, 0)
1251  if ((Predicate == ICmpInst::ICMP_EQ || Predicate == ICmpInst::ICMP_NE) &&
1252  CE0->getOpcode() == Instruction::Or && Ops1->isNullValue()) {
1254  Predicate, CE0->getOperand(0), Ops1, DL, TLI);
1256  Predicate, CE0->getOperand(1), Ops1, DL, TLI);
1257  unsigned OpC =
1258  Predicate == ICmpInst::ICMP_EQ ? Instruction::And : Instruction::Or;
1259  return ConstantFoldBinaryOpOperands(OpC, LHS, RHS, DL);
1260  }
1261  } else if (isa<ConstantExpr>(Ops1)) {
1262  // If RHS is a constant expression, but the left side isn't, swap the
1263  // operands and try again.
1264  Predicate = ICmpInst::getSwappedPredicate((ICmpInst::Predicate)Predicate);
1265  return ConstantFoldCompareInstOperands(Predicate, Ops1, Ops0, DL, TLI);
1266  }
1267 
1268  return ConstantExpr::getCompare(Predicate, Ops0, Ops1);
1269 }
1270 
1272  const DataLayout &DL) {
1273  assert(Instruction::isUnaryOp(Opcode));
1274 
1275  return ConstantExpr::get(Opcode, Op);
1276 }
1277 
1279  Constant *RHS,
1280  const DataLayout &DL) {
1282  if (isa<ConstantExpr>(LHS) || isa<ConstantExpr>(RHS))
1283  if (Constant *C = SymbolicallyEvaluateBinop(Opcode, LHS, RHS, DL))
1284  return C;
1285 
1286  return ConstantExpr::get(Opcode, LHS, RHS);
1287 }
1288 
1290  Type *DestTy, const DataLayout &DL) {
1291  assert(Instruction::isCast(Opcode));
1292  switch (Opcode) {
1293  default:
1294  llvm_unreachable("Missing case");
1295  case Instruction::PtrToInt:
1296  // If the input is a inttoptr, eliminate the pair. This requires knowing
1297  // the width of a pointer, so it can't be done in ConstantExpr::getCast.
1298  if (auto *CE = dyn_cast<ConstantExpr>(C)) {
1299  if (CE->getOpcode() == Instruction::IntToPtr) {
1300  Constant *Input = CE->getOperand(0);
1301  unsigned InWidth = Input->getType()->getScalarSizeInBits();
1302  unsigned PtrWidth = DL.getPointerTypeSizeInBits(CE->getType());
1303  if (PtrWidth < InWidth) {
1304  Constant *Mask =
1305  ConstantInt::get(CE->getContext(),
1306  APInt::getLowBitsSet(InWidth, PtrWidth));
1307  Input = ConstantExpr::getAnd(Input, Mask);
1308  }
1309  // Do a zext or trunc to get to the dest size.
1310  return ConstantExpr::getIntegerCast(Input, DestTy, false);
1311  }
1312  }
1313  return ConstantExpr::getCast(Opcode, C, DestTy);
1314  case Instruction::IntToPtr:
1315  // If the input is a ptrtoint, turn the pair into a ptr to ptr bitcast if
1316  // the int size is >= the ptr size and the address spaces are the same.
1317  // This requires knowing the width of a pointer, so it can't be done in
1318  // ConstantExpr::getCast.
1319  if (auto *CE = dyn_cast<ConstantExpr>(C)) {
1320  if (CE->getOpcode() == Instruction::PtrToInt) {
1321  Constant *SrcPtr = CE->getOperand(0);
1322  unsigned SrcPtrSize = DL.getPointerTypeSizeInBits(SrcPtr->getType());
1323  unsigned MidIntSize = CE->getType()->getScalarSizeInBits();
1324 
1325  if (MidIntSize >= SrcPtrSize) {
1326  unsigned SrcAS = SrcPtr->getType()->getPointerAddressSpace();
1327  if (SrcAS == DestTy->getPointerAddressSpace())
1328  return FoldBitCast(CE->getOperand(0), DestTy, DL);
1329  }
1330  }
1331  }
1332 
1333  return ConstantExpr::getCast(Opcode, C, DestTy);
1334  case Instruction::Trunc:
1335  case Instruction::ZExt:
1336  case Instruction::SExt:
1337  case Instruction::FPTrunc:
1338  case Instruction::FPExt:
1339  case Instruction::UIToFP:
1340  case Instruction::SIToFP:
1341  case Instruction::FPToUI:
1342  case Instruction::FPToSI:
1343  case Instruction::AddrSpaceCast:
1344  return ConstantExpr::getCast(Opcode, C, DestTy);
1345  case Instruction::BitCast:
1346  return FoldBitCast(C, DestTy, DL);
1347  }
1348 }
1349 
1351  ConstantExpr *CE) {
1352  if (!CE->getOperand(1)->isNullValue())
1353  return nullptr; // Do not allow stepping over the value!
1354 
1355  // Loop over all of the operands, tracking down which value we are
1356  // addressing.
1357  for (unsigned i = 2, e = CE->getNumOperands(); i != e; ++i) {
1358  C = C->getAggregateElement(CE->getOperand(i));
1359  if (!C)
1360  return nullptr;
1361  }
1362  return C;
1363 }
1364 
1365 Constant *
1367  ArrayRef<Constant *> Indices) {
1368  // Loop over all of the operands, tracking down which value we are
1369  // addressing.
1370  for (Constant *Index : Indices) {
1371  C = C->getAggregateElement(Index);
1372  if (!C)
1373  return nullptr;
1374  }
1375  return C;
1376 }
1377 
1378 //===----------------------------------------------------------------------===//
1379 // Constant Folding for Calls
1380 //
1381 
1382 bool llvm::canConstantFoldCallTo(const CallBase *Call, const Function *F) {
1383  if (Call->isNoBuiltin() || Call->isStrictFP())
1384  return false;
1385  switch (F->getIntrinsicID()) {
1386  case Intrinsic::fabs:
1387  case Intrinsic::minnum:
1388  case Intrinsic::maxnum:
1389  case Intrinsic::minimum:
1390  case Intrinsic::maximum:
1391  case Intrinsic::log:
1392  case Intrinsic::log2:
1393  case Intrinsic::log10:
1394  case Intrinsic::exp:
1395  case Intrinsic::exp2:
1396  case Intrinsic::floor:
1397  case Intrinsic::ceil:
1398  case Intrinsic::sqrt:
1399  case Intrinsic::sin:
1400  case Intrinsic::cos:
1401  case Intrinsic::trunc:
1402  case Intrinsic::rint:
1403  case Intrinsic::nearbyint:
1404  case Intrinsic::pow:
1405  case Intrinsic::powi:
1406  case Intrinsic::bswap:
1407  case Intrinsic::ctpop:
1408  case Intrinsic::ctlz:
1409  case Intrinsic::cttz:
1410  case Intrinsic::fshl:
1411  case Intrinsic::fshr:
1412  case Intrinsic::fma:
1413  case Intrinsic::fmuladd:
1414  case Intrinsic::copysign:
1415  case Intrinsic::launder_invariant_group:
1416  case Intrinsic::strip_invariant_group:
1417  case Intrinsic::round:
1418  case Intrinsic::masked_load:
1419  case Intrinsic::sadd_with_overflow:
1420  case Intrinsic::uadd_with_overflow:
1421  case Intrinsic::ssub_with_overflow:
1422  case Intrinsic::usub_with_overflow:
1423  case Intrinsic::smul_with_overflow:
1424  case Intrinsic::umul_with_overflow:
1425  case Intrinsic::sadd_sat:
1426  case Intrinsic::uadd_sat:
1427  case Intrinsic::ssub_sat:
1428  case Intrinsic::usub_sat:
1429  case Intrinsic::smul_fix:
1430  case Intrinsic::smul_fix_sat:
1431  case Intrinsic::convert_from_fp16:
1432  case Intrinsic::convert_to_fp16:
1433  case Intrinsic::bitreverse:
1434  case Intrinsic::x86_sse_cvtss2si:
1435  case Intrinsic::x86_sse_cvtss2si64:
1436  case Intrinsic::x86_sse_cvttss2si:
1437  case Intrinsic::x86_sse_cvttss2si64:
1438  case Intrinsic::x86_sse2_cvtsd2si:
1439  case Intrinsic::x86_sse2_cvtsd2si64:
1440  case Intrinsic::x86_sse2_cvttsd2si:
1441  case Intrinsic::x86_sse2_cvttsd2si64:
1442  case Intrinsic::x86_avx512_vcvtss2si32:
1443  case Intrinsic::x86_avx512_vcvtss2si64:
1444  case Intrinsic::x86_avx512_cvttss2si:
1445  case Intrinsic::x86_avx512_cvttss2si64:
1446  case Intrinsic::x86_avx512_vcvtsd2si32:
1447  case Intrinsic::x86_avx512_vcvtsd2si64:
1448  case Intrinsic::x86_avx512_cvttsd2si:
1449  case Intrinsic::x86_avx512_cvttsd2si64:
1450  case Intrinsic::x86_avx512_vcvtss2usi32:
1451  case Intrinsic::x86_avx512_vcvtss2usi64:
1452  case Intrinsic::x86_avx512_cvttss2usi:
1453  case Intrinsic::x86_avx512_cvttss2usi64:
1454  case Intrinsic::x86_avx512_vcvtsd2usi32:
1455  case Intrinsic::x86_avx512_vcvtsd2usi64:
1456  case Intrinsic::x86_avx512_cvttsd2usi:
1457  case Intrinsic::x86_avx512_cvttsd2usi64:
1458  case Intrinsic::is_constant:
1459  return true;
1460  default:
1461  return false;
1462  case Intrinsic::not_intrinsic: break;
1463  }
1464 
1465  if (!F->hasName())
1466  return false;
1467  StringRef Name = F->getName();
1468 
1469  // In these cases, the check of the length is required. We don't want to
1470  // return true for a name like "cos\0blah" which strcmp would return equal to
1471  // "cos", but has length 8.
1472  switch (Name[0]) {
1473  default:
1474  return false;
1475  case 'a':
1476  return Name == "acos" || Name == "asin" || Name == "atan" ||
1477  Name == "atan2" || Name == "acosf" || Name == "asinf" ||
1478  Name == "atanf" || Name == "atan2f";
1479  case 'c':
1480  return Name == "ceil" || Name == "cos" || Name == "cosh" ||
1481  Name == "ceilf" || Name == "cosf" || Name == "coshf";
1482  case 'e':
1483  return Name == "exp" || Name == "exp2" || Name == "expf" || Name == "exp2f";
1484  case 'f':
1485  return Name == "fabs" || Name == "floor" || Name == "fmod" ||
1486  Name == "fabsf" || Name == "floorf" || Name == "fmodf";
1487  case 'l':
1488  return Name == "log" || Name == "log10" || Name == "logf" ||
1489  Name == "log10f";
1490  case 'p':
1491  return Name == "pow" || Name == "powf";
1492  case 'r':
1493  return Name == "round" || Name == "roundf";
1494  case 's':
1495  return Name == "sin" || Name == "sinh" || Name == "sqrt" ||
1496  Name == "sinf" || Name == "sinhf" || Name == "sqrtf";
1497  case 't':
1498  return Name == "tan" || Name == "tanh" || Name == "tanf" || Name == "tanhf";
1499  case '_':
1500 
1501  // Check for various function names that get used for the math functions
1502  // when the header files are preprocessed with the macro
1503  // __FINITE_MATH_ONLY__ enabled.
1504  // The '12' here is the length of the shortest name that can match.
1505  // We need to check the size before looking at Name[1] and Name[2]
1506  // so we may as well check a limit that will eliminate mismatches.
1507  if (Name.size() < 12 || Name[1] != '_')
1508  return false;
1509  switch (Name[2]) {
1510  default:
1511  return false;
1512  case 'a':
1513  return Name == "__acos_finite" || Name == "__acosf_finite" ||
1514  Name == "__asin_finite" || Name == "__asinf_finite" ||
1515  Name == "__atan2_finite" || Name == "__atan2f_finite";
1516  case 'c':
1517  return Name == "__cosh_finite" || Name == "__coshf_finite";
1518  case 'e':
1519  return Name == "__exp_finite" || Name == "__expf_finite" ||
1520  Name == "__exp2_finite" || Name == "__exp2f_finite";
1521  case 'l':
1522  return Name == "__log_finite" || Name == "__logf_finite" ||
1523  Name == "__log10_finite" || Name == "__log10f_finite";
1524  case 'p':
1525  return Name == "__pow_finite" || Name == "__powf_finite";
1526  case 's':
1527  return Name == "__sinh_finite" || Name == "__sinhf_finite";
1528  }
1529  }
1530 }
1531 
1532 namespace {
1533 
1534 Constant *GetConstantFoldFPValue(double V, Type *Ty) {
1535  if (Ty->isHalfTy() || Ty->isFloatTy()) {
1536  APFloat APF(V);
1537  bool unused;
1539  return ConstantFP::get(Ty->getContext(), APF);
1540  }
1541  if (Ty->isDoubleTy())
1542  return ConstantFP::get(Ty->getContext(), APFloat(V));
1543  llvm_unreachable("Can only constant fold half/float/double");
1544 }
1545 
1546 /// Clear the floating-point exception state.
1547 inline void llvm_fenv_clearexcept() {
1548 #if defined(HAVE_FENV_H) && HAVE_DECL_FE_ALL_EXCEPT
1549  feclearexcept(FE_ALL_EXCEPT);
1550 #endif
1551  errno = 0;
1552 }
1553 
1554 /// Test if a floating-point exception was raised.
1555 inline bool llvm_fenv_testexcept() {
1556  int errno_val = errno;
1557  if (errno_val == ERANGE || errno_val == EDOM)
1558  return true;
1559 #if defined(HAVE_FENV_H) && HAVE_DECL_FE_ALL_EXCEPT && HAVE_DECL_FE_INEXACT
1560  if (fetestexcept(FE_ALL_EXCEPT & ~FE_INEXACT))
1561  return true;
1562 #endif
1563  return false;
1564 }
1565 
1566 Constant *ConstantFoldFP(double (*NativeFP)(double), double V, Type *Ty) {
1567  llvm_fenv_clearexcept();
1568  V = NativeFP(V);
1569  if (llvm_fenv_testexcept()) {
1570  llvm_fenv_clearexcept();
1571  return nullptr;
1572  }
1573 
1574  return GetConstantFoldFPValue(V, Ty);
1575 }
1576 
1577 Constant *ConstantFoldBinaryFP(double (*NativeFP)(double, double), double V,
1578  double W, Type *Ty) {
1579  llvm_fenv_clearexcept();
1580  V = NativeFP(V, W);
1581  if (llvm_fenv_testexcept()) {
1582  llvm_fenv_clearexcept();
1583  return nullptr;
1584  }
1585 
1586  return GetConstantFoldFPValue(V, Ty);
1587 }
1588 
1589 /// Attempt to fold an SSE floating point to integer conversion of a constant
1590 /// floating point. If roundTowardZero is false, the default IEEE rounding is
1591 /// used (toward nearest, ties to even). This matches the behavior of the
1592 /// non-truncating SSE instructions in the default rounding mode. The desired
1593 /// integer type Ty is used to select how many bits are available for the
1594 /// result. Returns null if the conversion cannot be performed, otherwise
1595 /// returns the Constant value resulting from the conversion.
1596 Constant *ConstantFoldSSEConvertToInt(const APFloat &Val, bool roundTowardZero,
1597  Type *Ty, bool IsSigned) {
1598  // All of these conversion intrinsics form an integer of at most 64bits.
1599  unsigned ResultWidth = Ty->getIntegerBitWidth();
1600  assert(ResultWidth <= 64 &&
1601  "Can only constant fold conversions to 64 and 32 bit ints");
1602 
1603  uint64_t UIntVal;
1604  bool isExact = false;
1608  Val.convertToInteger(makeMutableArrayRef(UIntVal), ResultWidth,
1609  IsSigned, mode, &isExact);
1610  if (status != APFloat::opOK &&
1611  (!roundTowardZero || status != APFloat::opInexact))
1612  return nullptr;
1613  return ConstantInt::get(Ty, UIntVal, IsSigned);
1614 }
1615 
1616 double getValueAsDouble(ConstantFP *Op) {
1617  Type *Ty = Op->getType();
1618 
1619  if (Ty->isFloatTy())
1620  return Op->getValueAPF().convertToFloat();
1621 
1622  if (Ty->isDoubleTy())
1623  return Op->getValueAPF().convertToDouble();
1624 
1625  bool unused;
1626  APFloat APF = Op->getValueAPF();
1628  return APF.convertToDouble();
1629 }
1630 
1631 static bool isManifestConstant(const Constant *c) {
1632  if (isa<ConstantData>(c)) {
1633  return true;
1634  } else if (isa<ConstantAggregate>(c) || isa<ConstantExpr>(c)) {
1635  for (const Value *subc : c->operand_values()) {
1636  if (!isManifestConstant(cast<Constant>(subc)))
1637  return false;
1638  }
1639  return true;
1640  }
1641  return false;
1642 }
1643 
1644 static bool getConstIntOrUndef(Value *Op, const APInt *&C) {
1645  if (auto *CI = dyn_cast<ConstantInt>(Op)) {
1646  C = &CI->getValue();
1647  return true;
1648  }
1649  if (isa<UndefValue>(Op)) {
1650  C = nullptr;
1651  return true;
1652  }
1653  return false;
1654 }
1655 
1656 static Constant *ConstantFoldScalarCall1(StringRef Name,
1657  Intrinsic::ID IntrinsicID,
1658  Type *Ty,
1659  ArrayRef<Constant *> Operands,
1660  const TargetLibraryInfo *TLI,
1661  const CallBase *Call) {
1662  assert(Operands.size() == 1 && "Wrong number of operands.");
1663 
1664  if (IntrinsicID == Intrinsic::is_constant) {
1665  // We know we have a "Constant" argument. But we want to only
1666  // return true for manifest constants, not those that depend on
1667  // constants with unknowable values, e.g. GlobalValue or BlockAddress.
1668  if (isManifestConstant(Operands[0]))
1669  return ConstantInt::getTrue(Ty->getContext());
1670  return nullptr;
1671  }
1672  if (isa<UndefValue>(Operands[0])) {
1673  // cosine(arg) is between -1 and 1. cosine(invalid arg) is NaN.
1674  // ctpop() is between 0 and bitwidth, pick 0 for undef.
1675  if (IntrinsicID == Intrinsic::cos ||
1676  IntrinsicID == Intrinsic::ctpop)
1677  return Constant::getNullValue(Ty);
1678  if (IntrinsicID == Intrinsic::bswap ||
1679  IntrinsicID == Intrinsic::bitreverse ||
1680  IntrinsicID == Intrinsic::launder_invariant_group ||
1681  IntrinsicID == Intrinsic::strip_invariant_group)
1682  return Operands[0];
1683  }
1684 
1685  if (isa<ConstantPointerNull>(Operands[0])) {
1686  // launder(null) == null == strip(null) iff in addrspace 0
1687  if (IntrinsicID == Intrinsic::launder_invariant_group ||
1688  IntrinsicID == Intrinsic::strip_invariant_group) {
1689  // If instruction is not yet put in a basic block (e.g. when cloning
1690  // a function during inlining), Call's caller may not be available.
1691  // So check Call's BB first before querying Call->getCaller.
1692  const Function *Caller =
1693  Call->getParent() ? Call->getCaller() : nullptr;
1694  if (Caller &&
1696  Caller, Operands[0]->getType()->getPointerAddressSpace())) {
1697  return Operands[0];
1698  }
1699  return nullptr;
1700  }
1701  }
1702 
1703  if (auto *Op = dyn_cast<ConstantFP>(Operands[0])) {
1704  if (IntrinsicID == Intrinsic::convert_to_fp16) {
1705  APFloat Val(Op->getValueAPF());
1706 
1707  bool lost = false;
1709 
1710  return ConstantInt::get(Ty->getContext(), Val.bitcastToAPInt());
1711  }
1712 
1713  if (!Ty->isHalfTy() && !Ty->isFloatTy() && !Ty->isDoubleTy())
1714  return nullptr;
1715 
1716  if (IntrinsicID == Intrinsic::round) {
1717  APFloat V = Op->getValueAPF();
1719  return ConstantFP::get(Ty->getContext(), V);
1720  }
1721 
1722  if (IntrinsicID == Intrinsic::floor) {
1723  APFloat V = Op->getValueAPF();
1725  return ConstantFP::get(Ty->getContext(), V);
1726  }
1727 
1728  if (IntrinsicID == Intrinsic::ceil) {
1729  APFloat V = Op->getValueAPF();
1731  return ConstantFP::get(Ty->getContext(), V);
1732  }
1733 
1734  if (IntrinsicID == Intrinsic::trunc) {
1735  APFloat V = Op->getValueAPF();
1737  return ConstantFP::get(Ty->getContext(), V);
1738  }
1739 
1740  if (IntrinsicID == Intrinsic::rint) {
1741  APFloat V = Op->getValueAPF();
1743  return ConstantFP::get(Ty->getContext(), V);
1744  }
1745 
1746  if (IntrinsicID == Intrinsic::nearbyint) {
1747  APFloat V = Op->getValueAPF();
1749  return ConstantFP::get(Ty->getContext(), V);
1750  }
1751 
1752  /// We only fold functions with finite arguments. Folding NaN and inf is
1753  /// likely to be aborted with an exception anyway, and some host libms
1754  /// have known errors raising exceptions.
1755  if (Op->getValueAPF().isNaN() || Op->getValueAPF().isInfinity())
1756  return nullptr;
1757 
1758  /// Currently APFloat versions of these functions do not exist, so we use
1759  /// the host native double versions. Float versions are not called
1760  /// directly but for all these it is true (float)(f((double)arg)) ==
1761  /// f(arg). Long double not supported yet.
1762  double V = getValueAsDouble(Op);
1763 
1764  switch (IntrinsicID) {
1765  default: break;
1766  case Intrinsic::fabs:
1767  return ConstantFoldFP(fabs, V, Ty);
1768  case Intrinsic::log2:
1769  return ConstantFoldFP(Log2, V, Ty);
1770  case Intrinsic::log:
1771  return ConstantFoldFP(log, V, Ty);
1772  case Intrinsic::log10:
1773  return ConstantFoldFP(log10, V, Ty);
1774  case Intrinsic::exp:
1775  return ConstantFoldFP(exp, V, Ty);
1776  case Intrinsic::exp2:
1777  return ConstantFoldFP(exp2, V, Ty);
1778  case Intrinsic::sin:
1779  return ConstantFoldFP(sin, V, Ty);
1780  case Intrinsic::cos:
1781  return ConstantFoldFP(cos, V, Ty);
1782  case Intrinsic::sqrt:
1783  return ConstantFoldFP(sqrt, V, Ty);
1784  }
1785 
1786  if (!TLI)
1787  return nullptr;
1788 
1789  char NameKeyChar = Name[0];
1790  if (Name[0] == '_' && Name.size() > 2 && Name[1] == '_')
1791  NameKeyChar = Name[2];
1792 
1793  switch (NameKeyChar) {
1794  case 'a':
1795  if ((Name == "acos" && TLI->has(LibFunc_acos)) ||
1796  (Name == "acosf" && TLI->has(LibFunc_acosf)) ||
1797  (Name == "__acos_finite" && TLI->has(LibFunc_acos_finite)) ||
1798  (Name == "__acosf_finite" && TLI->has(LibFunc_acosf_finite)))
1799  return ConstantFoldFP(acos, V, Ty);
1800  else if ((Name == "asin" && TLI->has(LibFunc_asin)) ||
1801  (Name == "asinf" && TLI->has(LibFunc_asinf)) ||
1802  (Name == "__asin_finite" && TLI->has(LibFunc_asin_finite)) ||
1803  (Name == "__asinf_finite" && TLI->has(LibFunc_asinf_finite)))
1804  return ConstantFoldFP(asin, V, Ty);
1805  else if ((Name == "atan" && TLI->has(LibFunc_atan)) ||
1806  (Name == "atanf" && TLI->has(LibFunc_atanf)))
1807  return ConstantFoldFP(atan, V, Ty);
1808  break;
1809  case 'c':
1810  if ((Name == "ceil" && TLI->has(LibFunc_ceil)) ||
1811  (Name == "ceilf" && TLI->has(LibFunc_ceilf)))
1812  return ConstantFoldFP(ceil, V, Ty);
1813  else if ((Name == "cos" && TLI->has(LibFunc_cos)) ||
1814  (Name == "cosf" && TLI->has(LibFunc_cosf)))
1815  return ConstantFoldFP(cos, V, Ty);
1816  else if ((Name == "cosh" && TLI->has(LibFunc_cosh)) ||
1817  (Name == "coshf" && TLI->has(LibFunc_coshf)) ||
1818  (Name == "__cosh_finite" && TLI->has(LibFunc_cosh_finite)) ||
1819  (Name == "__coshf_finite" && TLI->has(LibFunc_coshf_finite)))
1820  return ConstantFoldFP(cosh, V, Ty);
1821  break;
1822  case 'e':
1823  if ((Name == "exp" && TLI->has(LibFunc_exp)) ||
1824  (Name == "expf" && TLI->has(LibFunc_expf)) ||
1825  (Name == "__exp_finite" && TLI->has(LibFunc_exp_finite)) ||
1826  (Name == "__expf_finite" && TLI->has(LibFunc_expf_finite)))
1827  return ConstantFoldFP(exp, V, Ty);
1828  if ((Name == "exp2" && TLI->has(LibFunc_exp2)) ||
1829  (Name == "exp2f" && TLI->has(LibFunc_exp2f)) ||
1830  (Name == "__exp2_finite" && TLI->has(LibFunc_exp2_finite)) ||
1831  (Name == "__exp2f_finite" && TLI->has(LibFunc_exp2f_finite)))
1832  // Constant fold exp2(x) as pow(2,x) in case the host doesn't have a
1833  // C99 library.
1834  return ConstantFoldBinaryFP(pow, 2.0, V, Ty);
1835  break;
1836  case 'f':
1837  if ((Name == "fabs" && TLI->has(LibFunc_fabs)) ||
1838  (Name == "fabsf" && TLI->has(LibFunc_fabsf)))
1839  return ConstantFoldFP(fabs, V, Ty);
1840  else if ((Name == "floor" && TLI->has(LibFunc_floor)) ||
1841  (Name == "floorf" && TLI->has(LibFunc_floorf)))
1842  return ConstantFoldFP(floor, V, Ty);
1843  break;
1844  case 'l':
1845  if ((Name == "log" && V > 0 && TLI->has(LibFunc_log)) ||
1846  (Name == "logf" && V > 0 && TLI->has(LibFunc_logf)) ||
1847  (Name == "__log_finite" && V > 0 &&
1848  TLI->has(LibFunc_log_finite)) ||
1849  (Name == "__logf_finite" && V > 0 &&
1850  TLI->has(LibFunc_logf_finite)))
1851  return ConstantFoldFP(log, V, Ty);
1852  else if ((Name == "log10" && V > 0 && TLI->has(LibFunc_log10)) ||
1853  (Name == "log10f" && V > 0 && TLI->has(LibFunc_log10f)) ||
1854  (Name == "__log10_finite" && V > 0 &&
1855  TLI->has(LibFunc_log10_finite)) ||
1856  (Name == "__log10f_finite" && V > 0 &&
1857  TLI->has(LibFunc_log10f_finite)))
1858  return ConstantFoldFP(log10, V, Ty);
1859  break;
1860  case 'r':
1861  if ((Name == "round" && TLI->has(LibFunc_round)) ||
1862  (Name == "roundf" && TLI->has(LibFunc_roundf)))
1863  return ConstantFoldFP(round, V, Ty);
1864  break;
1865  case 's':
1866  if ((Name == "sin" && TLI->has(LibFunc_sin)) ||
1867  (Name == "sinf" && TLI->has(LibFunc_sinf)))
1868  return ConstantFoldFP(sin, V, Ty);
1869  else if ((Name == "sinh" && TLI->has(LibFunc_sinh)) ||
1870  (Name == "sinhf" && TLI->has(LibFunc_sinhf)) ||
1871  (Name == "__sinh_finite" && TLI->has(LibFunc_sinh_finite)) ||
1872  (Name == "__sinhf_finite" && TLI->has(LibFunc_sinhf_finite)))
1873  return ConstantFoldFP(sinh, V, Ty);
1874  else if ((Name == "sqrt" && V >= 0 && TLI->has(LibFunc_sqrt)) ||
1875  (Name == "sqrtf" && V >= 0 && TLI->has(LibFunc_sqrtf)))
1876  return ConstantFoldFP(sqrt, V, Ty);
1877  break;
1878  case 't':
1879  if ((Name == "tan" && TLI->has(LibFunc_tan)) ||
1880  (Name == "tanf" && TLI->has(LibFunc_tanf)))
1881  return ConstantFoldFP(tan, V, Ty);
1882  else if ((Name == "tanh" && TLI->has(LibFunc_tanh)) ||
1883  (Name == "tanhf" && TLI->has(LibFunc_tanhf)))
1884  return ConstantFoldFP(tanh, V, Ty);
1885  break;
1886  default:
1887  break;
1888  }
1889  return nullptr;
1890  }
1891 
1892  if (auto *Op = dyn_cast<ConstantInt>(Operands[0])) {
1893  switch (IntrinsicID) {
1894  case Intrinsic::bswap:
1895  return ConstantInt::get(Ty->getContext(), Op->getValue().byteSwap());
1896  case Intrinsic::ctpop:
1897  return ConstantInt::get(Ty, Op->getValue().countPopulation());
1898  case Intrinsic::bitreverse:
1899  return ConstantInt::get(Ty->getContext(), Op->getValue().reverseBits());
1900  case Intrinsic::convert_from_fp16: {
1901  APFloat Val(APFloat::IEEEhalf(), Op->getValue());
1902 
1903  bool lost = false;
1906 
1907  // Conversion is always precise.
1908  (void)status;
1909  assert(status == APFloat::opOK && !lost &&
1910  "Precision lost during fp16 constfolding");
1911 
1912  return ConstantFP::get(Ty->getContext(), Val);
1913  }
1914  default:
1915  return nullptr;
1916  }
1917  }
1918 
1919  // Support ConstantVector in case we have an Undef in the top.
1920  if (isa<ConstantVector>(Operands[0]) ||
1921  isa<ConstantDataVector>(Operands[0])) {
1922  auto *Op = cast<Constant>(Operands[0]);
1923  switch (IntrinsicID) {
1924  default: break;
1925  case Intrinsic::x86_sse_cvtss2si:
1926  case Intrinsic::x86_sse_cvtss2si64:
1927  case Intrinsic::x86_sse2_cvtsd2si:
1928  case Intrinsic::x86_sse2_cvtsd2si64:
1929  if (ConstantFP *FPOp =
1930  dyn_cast_or_null<ConstantFP>(Op->getAggregateElement(0U)))
1931  return ConstantFoldSSEConvertToInt(FPOp->getValueAPF(),
1932  /*roundTowardZero=*/false, Ty,
1933  /*IsSigned*/true);
1934  break;
1935  case Intrinsic::x86_sse_cvttss2si:
1936  case Intrinsic::x86_sse_cvttss2si64:
1937  case Intrinsic::x86_sse2_cvttsd2si:
1938  case Intrinsic::x86_sse2_cvttsd2si64:
1939  if (ConstantFP *FPOp =
1940  dyn_cast_or_null<ConstantFP>(Op->getAggregateElement(0U)))
1941  return ConstantFoldSSEConvertToInt(FPOp->getValueAPF(),
1942  /*roundTowardZero=*/true, Ty,
1943  /*IsSigned*/true);
1944  break;
1945  }
1946  }
1947 
1948  return nullptr;
1949 }
1950 
1951 static Constant *ConstantFoldScalarCall2(StringRef Name,
1952  Intrinsic::ID IntrinsicID,
1953  Type *Ty,
1954  ArrayRef<Constant *> Operands,
1955  const TargetLibraryInfo *TLI,
1956  const CallBase *Call) {
1957  assert(Operands.size() == 2 && "Wrong number of operands.");
1958 
1959  if (auto *Op1 = dyn_cast<ConstantFP>(Operands[0])) {
1960  if (!Ty->isHalfTy() && !Ty->isFloatTy() && !Ty->isDoubleTy())
1961  return nullptr;
1962  double Op1V = getValueAsDouble(Op1);
1963 
1964  if (auto *Op2 = dyn_cast<ConstantFP>(Operands[1])) {
1965  if (Op2->getType() != Op1->getType())
1966  return nullptr;
1967 
1968  double Op2V = getValueAsDouble(Op2);
1969  if (IntrinsicID == Intrinsic::pow) {
1970  return ConstantFoldBinaryFP(pow, Op1V, Op2V, Ty);
1971  }
1972  if (IntrinsicID == Intrinsic::copysign) {
1973  APFloat V1 = Op1->getValueAPF();
1974  const APFloat &V2 = Op2->getValueAPF();
1975  V1.copySign(V2);
1976  return ConstantFP::get(Ty->getContext(), V1);
1977  }
1978 
1979  if (IntrinsicID == Intrinsic::minnum) {
1980  const APFloat &C1 = Op1->getValueAPF();
1981  const APFloat &C2 = Op2->getValueAPF();
1982  return ConstantFP::get(Ty->getContext(), minnum(C1, C2));
1983  }
1984 
1985  if (IntrinsicID == Intrinsic::maxnum) {
1986  const APFloat &C1 = Op1->getValueAPF();
1987  const APFloat &C2 = Op2->getValueAPF();
1988  return ConstantFP::get(Ty->getContext(), maxnum(C1, C2));
1989  }
1990 
1991  if (IntrinsicID == Intrinsic::minimum) {
1992  const APFloat &C1 = Op1->getValueAPF();
1993  const APFloat &C2 = Op2->getValueAPF();
1994  return ConstantFP::get(Ty->getContext(), minimum(C1, C2));
1995  }
1996 
1997  if (IntrinsicID == Intrinsic::maximum) {
1998  const APFloat &C1 = Op1->getValueAPF();
1999  const APFloat &C2 = Op2->getValueAPF();
2000  return ConstantFP::get(Ty->getContext(), maximum(C1, C2));
2001  }
2002 
2003  if (!TLI)
2004  return nullptr;
2005  if ((Name == "pow" && TLI->has(LibFunc_pow)) ||
2006  (Name == "powf" && TLI->has(LibFunc_powf)) ||
2007  (Name == "__pow_finite" && TLI->has(LibFunc_pow_finite)) ||
2008  (Name == "__powf_finite" && TLI->has(LibFunc_powf_finite)))
2009  return ConstantFoldBinaryFP(pow, Op1V, Op2V, Ty);
2010  if ((Name == "fmod" && TLI->has(LibFunc_fmod)) ||
2011  (Name == "fmodf" && TLI->has(LibFunc_fmodf)))
2012  return ConstantFoldBinaryFP(fmod, Op1V, Op2V, Ty);
2013  if ((Name == "atan2" && TLI->has(LibFunc_atan2)) ||
2014  (Name == "atan2f" && TLI->has(LibFunc_atan2f)) ||
2015  (Name == "__atan2_finite" && TLI->has(LibFunc_atan2_finite)) ||
2016  (Name == "__atan2f_finite" && TLI->has(LibFunc_atan2f_finite)))
2017  return ConstantFoldBinaryFP(atan2, Op1V, Op2V, Ty);
2018  } else if (auto *Op2C = dyn_cast<ConstantInt>(Operands[1])) {
2019  if (IntrinsicID == Intrinsic::powi && Ty->isHalfTy())
2020  return ConstantFP::get(Ty->getContext(),
2021  APFloat((float)std::pow((float)Op1V,
2022  (int)Op2C->getZExtValue())));
2023  if (IntrinsicID == Intrinsic::powi && Ty->isFloatTy())
2024  return ConstantFP::get(Ty->getContext(),
2025  APFloat((float)std::pow((float)Op1V,
2026  (int)Op2C->getZExtValue())));
2027  if (IntrinsicID == Intrinsic::powi && Ty->isDoubleTy())
2028  return ConstantFP::get(Ty->getContext(),
2029  APFloat((double)std::pow((double)Op1V,
2030  (int)Op2C->getZExtValue())));
2031  }
2032  return nullptr;
2033  }
2034 
2035  if (Operands[0]->getType()->isIntegerTy() &&
2036  Operands[1]->getType()->isIntegerTy()) {
2037  const APInt *C0, *C1;
2038  if (!getConstIntOrUndef(Operands[0], C0) ||
2039  !getConstIntOrUndef(Operands[1], C1))
2040  return nullptr;
2041 
2042  switch (IntrinsicID) {
2043  default: break;
2044  case Intrinsic::smul_with_overflow:
2045  case Intrinsic::umul_with_overflow:
2046  // Even if both operands are undef, we cannot fold muls to undef
2047  // in the general case. For example, on i2 there are no inputs
2048  // that would produce { i2 -1, i1 true } as the result.
2049  if (!C0 || !C1)
2050  return Constant::getNullValue(Ty);
2052  case Intrinsic::sadd_with_overflow:
2053  case Intrinsic::uadd_with_overflow:
2054  case Intrinsic::ssub_with_overflow:
2055  case Intrinsic::usub_with_overflow: {
2056  if (!C0 || !C1)
2057  return UndefValue::get(Ty);
2058 
2059  APInt Res;
2060  bool Overflow;
2061  switch (IntrinsicID) {
2062  default: llvm_unreachable("Invalid case");
2063  case Intrinsic::sadd_with_overflow:
2064  Res = C0->sadd_ov(*C1, Overflow);
2065  break;
2066  case Intrinsic::uadd_with_overflow:
2067  Res = C0->uadd_ov(*C1, Overflow);
2068  break;
2069  case Intrinsic::ssub_with_overflow:
2070  Res = C0->ssub_ov(*C1, Overflow);
2071  break;
2072  case Intrinsic::usub_with_overflow:
2073  Res = C0->usub_ov(*C1, Overflow);
2074  break;
2075  case Intrinsic::smul_with_overflow:
2076  Res = C0->smul_ov(*C1, Overflow);
2077  break;
2078  case Intrinsic::umul_with_overflow:
2079  Res = C0->umul_ov(*C1, Overflow);
2080  break;
2081  }
2082  Constant *Ops[] = {
2083  ConstantInt::get(Ty->getContext(), Res),
2084  ConstantInt::get(Type::getInt1Ty(Ty->getContext()), Overflow)
2085  };
2086  return ConstantStruct::get(cast<StructType>(Ty), Ops);
2087  }
2088  case Intrinsic::uadd_sat:
2089  case Intrinsic::sadd_sat:
2090  if (!C0 && !C1)
2091  return UndefValue::get(Ty);
2092  if (!C0 || !C1)
2093  return Constant::getAllOnesValue(Ty);
2094  if (IntrinsicID == Intrinsic::uadd_sat)
2095  return ConstantInt::get(Ty, C0->uadd_sat(*C1));
2096  else
2097  return ConstantInt::get(Ty, C0->sadd_sat(*C1));
2098  case Intrinsic::usub_sat:
2099  case Intrinsic::ssub_sat:
2100  if (!C0 && !C1)
2101  return UndefValue::get(Ty);
2102  if (!C0 || !C1)
2103  return Constant::getNullValue(Ty);
2104  if (IntrinsicID == Intrinsic::usub_sat)
2105  return ConstantInt::get(Ty, C0->usub_sat(*C1));
2106  else
2107  return ConstantInt::get(Ty, C0->ssub_sat(*C1));
2108  case Intrinsic::cttz:
2109  case Intrinsic::ctlz:
2110  assert(C1 && "Must be constant int");
2111 
2112  // cttz(0, 1) and ctlz(0, 1) are undef.
2113  if (C1->isOneValue() && (!C0 || C0->isNullValue()))
2114  return UndefValue::get(Ty);
2115  if (!C0)
2116  return Constant::getNullValue(Ty);
2117  if (IntrinsicID == Intrinsic::cttz)
2118  return ConstantInt::get(Ty, C0->countTrailingZeros());
2119  else
2120  return ConstantInt::get(Ty, C0->countLeadingZeros());
2121  }
2122 
2123  return nullptr;
2124  }
2125 
2126  // Support ConstantVector in case we have an Undef in the top.
2127  if ((isa<ConstantVector>(Operands[0]) ||
2128  isa<ConstantDataVector>(Operands[0])) &&
2129  // Check for default rounding mode.
2130  // FIXME: Support other rounding modes?
2131  isa<ConstantInt>(Operands[1]) &&
2132  cast<ConstantInt>(Operands[1])->getValue() == 4) {
2133  auto *Op = cast<Constant>(Operands[0]);
2134  switch (IntrinsicID) {
2135  default: break;
2136  case Intrinsic::x86_avx512_vcvtss2si32:
2137  case Intrinsic::x86_avx512_vcvtss2si64:
2138  case Intrinsic::x86_avx512_vcvtsd2si32:
2139  case Intrinsic::x86_avx512_vcvtsd2si64:
2140  if (ConstantFP *FPOp =
2141  dyn_cast_or_null<ConstantFP>(Op->getAggregateElement(0U)))
2142  return ConstantFoldSSEConvertToInt(FPOp->getValueAPF(),
2143  /*roundTowardZero=*/false, Ty,
2144  /*IsSigned*/true);
2145  break;
2146  case Intrinsic::x86_avx512_vcvtss2usi32:
2147  case Intrinsic::x86_avx512_vcvtss2usi64:
2148  case Intrinsic::x86_avx512_vcvtsd2usi32:
2149  case Intrinsic::x86_avx512_vcvtsd2usi64:
2150  if (ConstantFP *FPOp =
2151  dyn_cast_or_null<ConstantFP>(Op->getAggregateElement(0U)))
2152  return ConstantFoldSSEConvertToInt(FPOp->getValueAPF(),
2153  /*roundTowardZero=*/false, Ty,
2154  /*IsSigned*/false);
2155  break;
2156  case Intrinsic::x86_avx512_cvttss2si:
2157  case Intrinsic::x86_avx512_cvttss2si64:
2158  case Intrinsic::x86_avx512_cvttsd2si:
2159  case Intrinsic::x86_avx512_cvttsd2si64:
2160  if (ConstantFP *FPOp =
2161  dyn_cast_or_null<ConstantFP>(Op->getAggregateElement(0U)))
2162  return ConstantFoldSSEConvertToInt(FPOp->getValueAPF(),
2163  /*roundTowardZero=*/true, Ty,
2164  /*IsSigned*/true);
2165  break;
2166  case Intrinsic::x86_avx512_cvttss2usi:
2167  case Intrinsic::x86_avx512_cvttss2usi64:
2168  case Intrinsic::x86_avx512_cvttsd2usi:
2169  case Intrinsic::x86_avx512_cvttsd2usi64:
2170  if (ConstantFP *FPOp =
2171  dyn_cast_or_null<ConstantFP>(Op->getAggregateElement(0U)))
2172  return ConstantFoldSSEConvertToInt(FPOp->getValueAPF(),
2173  /*roundTowardZero=*/true, Ty,
2174  /*IsSigned*/false);
2175  break;
2176  }
2177  }
2178  return nullptr;
2179 }
2180 
2181 static Constant *ConstantFoldScalarCall3(StringRef Name,
2182  Intrinsic::ID IntrinsicID,
2183  Type *Ty,
2184  ArrayRef<Constant *> Operands,
2185  const TargetLibraryInfo *TLI,
2186  const CallBase *Call) {
2187  assert(Operands.size() == 3 && "Wrong number of operands.");
2188 
2189  if (const auto *Op1 = dyn_cast<ConstantFP>(Operands[0])) {
2190  if (const auto *Op2 = dyn_cast<ConstantFP>(Operands[1])) {
2191  if (const auto *Op3 = dyn_cast<ConstantFP>(Operands[2])) {
2192  switch (IntrinsicID) {
2193  default: break;
2194  case Intrinsic::fma:
2195  case Intrinsic::fmuladd: {
2196  APFloat V = Op1->getValueAPF();
2197  APFloat::opStatus s = V.fusedMultiplyAdd(Op2->getValueAPF(),
2198  Op3->getValueAPF(),
2200  if (s != APFloat::opInvalidOp)
2201  return ConstantFP::get(Ty->getContext(), V);
2202 
2203  return nullptr;
2204  }
2205  }
2206  }
2207  }
2208  }
2209 
2210  if (const auto *Op1 = dyn_cast<ConstantInt>(Operands[0])) {
2211  if (const auto *Op2 = dyn_cast<ConstantInt>(Operands[1])) {
2212  if (const auto *Op3 = dyn_cast<ConstantInt>(Operands[2])) {
2213  switch (IntrinsicID) {
2214  default: break;
2215  case Intrinsic::smul_fix:
2216  case Intrinsic::smul_fix_sat: {
2217  // This code performs rounding towards negative infinity in case the
2218  // result cannot be represented exactly for the given scale. Targets
2219  // that do care about rounding should use a target hook for specifying
2220  // how rounding should be done, and provide their own folding to be
2221  // consistent with rounding. This is the same approach as used by
2222  // DAGTypeLegalizer::ExpandIntRes_MULFIX.
2223  APInt Lhs = Op1->getValue();
2224  APInt Rhs = Op2->getValue();
2225  unsigned Scale = Op3->getValue().getZExtValue();
2226  unsigned Width = Lhs.getBitWidth();
2227  assert(Scale < Width && "Illegal scale.");
2228  unsigned ExtendedWidth = Width * 2;
2229  APInt Product = (Lhs.sextOrSelf(ExtendedWidth) *
2230  Rhs.sextOrSelf(ExtendedWidth)).ashr(Scale);
2231  if (IntrinsicID == Intrinsic::smul_fix_sat) {
2232  APInt MaxValue =
2233  APInt::getSignedMaxValue(Width).sextOrSelf(ExtendedWidth);
2234  APInt MinValue =
2235  APInt::getSignedMinValue(Width).sextOrSelf(ExtendedWidth);
2236  Product = APIntOps::smin(Product, MaxValue);
2237  Product = APIntOps::smax(Product, MinValue);
2238  }
2239  return ConstantInt::get(Ty->getContext(),
2240  Product.sextOrTrunc(Width));
2241  }
2242  }
2243  }
2244  }
2245  }
2246 
2247  if (IntrinsicID == Intrinsic::fshl || IntrinsicID == Intrinsic::fshr) {
2248  const APInt *C0, *C1, *C2;
2249  if (!getConstIntOrUndef(Operands[0], C0) ||
2250  !getConstIntOrUndef(Operands[1], C1) ||
2251  !getConstIntOrUndef(Operands[2], C2))
2252  return nullptr;
2253 
2254  bool IsRight = IntrinsicID == Intrinsic::fshr;
2255  if (!C2)
2256  return Operands[IsRight ? 1 : 0];
2257  if (!C0 && !C1)
2258  return UndefValue::get(Ty);
2259 
2260  // The shift amount is interpreted as modulo the bitwidth. If the shift
2261  // amount is effectively 0, avoid UB due to oversized inverse shift below.
2262  unsigned BitWidth = C2->getBitWidth();
2263  unsigned ShAmt = C2->urem(BitWidth);
2264  if (!ShAmt)
2265  return Operands[IsRight ? 1 : 0];
2266 
2267  // (C0 << ShlAmt) | (C1 >> LshrAmt)
2268  unsigned LshrAmt = IsRight ? ShAmt : BitWidth - ShAmt;
2269  unsigned ShlAmt = !IsRight ? ShAmt : BitWidth - ShAmt;
2270  if (!C0)
2271  return ConstantInt::get(Ty, C1->lshr(LshrAmt));
2272  if (!C1)
2273  return ConstantInt::get(Ty, C0->shl(ShlAmt));
2274  return ConstantInt::get(Ty, C0->shl(ShlAmt) | C1->lshr(LshrAmt));
2275  }
2276 
2277  return nullptr;
2278 }
2279 
2280 static Constant *ConstantFoldScalarCall(StringRef Name,
2281  Intrinsic::ID IntrinsicID,
2282  Type *Ty,
2283  ArrayRef<Constant *> Operands,
2284  const TargetLibraryInfo *TLI,
2285  const CallBase *Call) {
2286  if (Operands.size() == 1)
2287  return ConstantFoldScalarCall1(Name, IntrinsicID, Ty, Operands, TLI, Call);
2288 
2289  if (Operands.size() == 2)
2290  return ConstantFoldScalarCall2(Name, IntrinsicID, Ty, Operands, TLI, Call);
2291 
2292  if (Operands.size() == 3)
2293  return ConstantFoldScalarCall3(Name, IntrinsicID, Ty, Operands, TLI, Call);
2294 
2295  return nullptr;
2296 }
2297 
2298 static Constant *ConstantFoldVectorCall(StringRef Name,
2299  Intrinsic::ID IntrinsicID,
2300  VectorType *VTy,
2301  ArrayRef<Constant *> Operands,
2302  const DataLayout &DL,
2303  const TargetLibraryInfo *TLI,
2304  const CallBase *Call) {
2306  SmallVector<Constant *, 4> Lane(Operands.size());
2307  Type *Ty = VTy->getElementType();
2308 
2309  if (IntrinsicID == Intrinsic::masked_load) {
2310  auto *SrcPtr = Operands[0];
2311  auto *Mask = Operands[2];
2312  auto *Passthru = Operands[3];
2313 
2314  Constant *VecData = ConstantFoldLoadFromConstPtr(SrcPtr, VTy, DL);
2315 
2316  SmallVector<Constant *, 32> NewElements;
2317  for (unsigned I = 0, E = VTy->getNumElements(); I != E; ++I) {
2318  auto *MaskElt = Mask->getAggregateElement(I);
2319  if (!MaskElt)
2320  break;
2321  auto *PassthruElt = Passthru->getAggregateElement(I);
2322  auto *VecElt = VecData ? VecData->getAggregateElement(I) : nullptr;
2323  if (isa<UndefValue>(MaskElt)) {
2324  if (PassthruElt)
2325  NewElements.push_back(PassthruElt);
2326  else if (VecElt)
2327  NewElements.push_back(VecElt);
2328  else
2329  return nullptr;
2330  }
2331  if (MaskElt->isNullValue()) {
2332  if (!PassthruElt)
2333  return nullptr;
2334  NewElements.push_back(PassthruElt);
2335  } else if (MaskElt->isOneValue()) {
2336  if (!VecElt)
2337  return nullptr;
2338  NewElements.push_back(VecElt);
2339  } else {
2340  return nullptr;
2341  }
2342  }
2343  if (NewElements.size() != VTy->getNumElements())
2344  return nullptr;
2345  return ConstantVector::get(NewElements);
2346  }
2347 
2348  for (unsigned I = 0, E = VTy->getNumElements(); I != E; ++I) {
2349  // Gather a column of constants.
2350  for (unsigned J = 0, JE = Operands.size(); J != JE; ++J) {
2351  // Some intrinsics use a scalar type for certain arguments.
2352  if (hasVectorInstrinsicScalarOpd(IntrinsicID, J)) {
2353  Lane[J] = Operands[J];
2354  continue;
2355  }
2356 
2357  Constant *Agg = Operands[J]->getAggregateElement(I);
2358  if (!Agg)
2359  return nullptr;
2360 
2361  Lane[J] = Agg;
2362  }
2363 
2364  // Use the regular scalar folding to simplify this column.
2365  Constant *Folded =
2366  ConstantFoldScalarCall(Name, IntrinsicID, Ty, Lane, TLI, Call);
2367  if (!Folded)
2368  return nullptr;
2369  Result[I] = Folded;
2370  }
2371 
2372  return ConstantVector::get(Result);
2373 }
2374 
2375 } // end anonymous namespace
2376 
2378  ArrayRef<Constant *> Operands,
2379  const TargetLibraryInfo *TLI) {
2380  if (Call->isNoBuiltin() || Call->isStrictFP())
2381  return nullptr;
2382  if (!F->hasName())
2383  return nullptr;
2384  StringRef Name = F->getName();
2385 
2386  Type *Ty = F->getReturnType();
2387 
2388  if (auto *VTy = dyn_cast<VectorType>(Ty))
2389  return ConstantFoldVectorCall(Name, F->getIntrinsicID(), VTy, Operands,
2390  F->getParent()->getDataLayout(), TLI, Call);
2391 
2392  return ConstantFoldScalarCall(Name, F->getIntrinsicID(), Ty, Operands, TLI,
2393  Call);
2394 }
2395 
2397  const TargetLibraryInfo *TLI) {
2398  // FIXME: Refactor this code; this duplicates logic in LibCallsShrinkWrap
2399  // (and to some extent ConstantFoldScalarCall).
2400  if (Call->isNoBuiltin() || Call->isStrictFP())
2401  return false;
2402  Function *F = Call->getCalledFunction();
2403  if (!F)
2404  return false;
2405 
2406  LibFunc Func;
2407  if (!TLI || !TLI->getLibFunc(*F, Func))
2408  return false;
2409 
2410  if (Call->getNumArgOperands() == 1) {
2411  if (ConstantFP *OpC = dyn_cast<ConstantFP>(Call->getArgOperand(0))) {
2412  const APFloat &Op = OpC->getValueAPF();
2413  switch (Func) {
2414  case LibFunc_logl:
2415  case LibFunc_log:
2416  case LibFunc_logf:
2417  case LibFunc_log2l:
2418  case LibFunc_log2:
2419  case LibFunc_log2f:
2420  case LibFunc_log10l:
2421  case LibFunc_log10:
2422  case LibFunc_log10f:
2423  return Op.isNaN() || (!Op.isZero() && !Op.isNegative());
2424 
2425  case LibFunc_expl:
2426  case LibFunc_exp:
2427  case LibFunc_expf:
2428  // FIXME: These boundaries are slightly conservative.
2429  if (OpC->getType()->isDoubleTy())
2430  return Op.compare(APFloat(-745.0)) != APFloat::cmpLessThan &&
2431  Op.compare(APFloat(709.0)) != APFloat::cmpGreaterThan;
2432  if (OpC->getType()->isFloatTy())
2433  return Op.compare(APFloat(-103.0f)) != APFloat::cmpLessThan &&
2434  Op.compare(APFloat(88.0f)) != APFloat::cmpGreaterThan;
2435  break;
2436 
2437  case LibFunc_exp2l:
2438  case LibFunc_exp2:
2439  case LibFunc_exp2f:
2440  // FIXME: These boundaries are slightly conservative.
2441  if (OpC->getType()->isDoubleTy())
2442  return Op.compare(APFloat(-1074.0)) != APFloat::cmpLessThan &&
2443  Op.compare(APFloat(1023.0)) != APFloat::cmpGreaterThan;
2444  if (OpC->getType()->isFloatTy())
2445  return Op.compare(APFloat(-149.0f)) != APFloat::cmpLessThan &&
2446  Op.compare(APFloat(127.0f)) != APFloat::cmpGreaterThan;
2447  break;
2448 
2449  case LibFunc_sinl:
2450  case LibFunc_sin:
2451  case LibFunc_sinf:
2452  case LibFunc_cosl:
2453  case LibFunc_cos:
2454  case LibFunc_cosf:
2455  return !Op.isInfinity();
2456 
2457  case LibFunc_tanl:
2458  case LibFunc_tan:
2459  case LibFunc_tanf: {
2460  // FIXME: Stop using the host math library.
2461  // FIXME: The computation isn't done in the right precision.
2462  Type *Ty = OpC->getType();
2463  if (Ty->isDoubleTy() || Ty->isFloatTy() || Ty->isHalfTy()) {
2464  double OpV = getValueAsDouble(OpC);
2465  return ConstantFoldFP(tan, OpV, Ty) != nullptr;
2466  }
2467  break;
2468  }
2469 
2470  case LibFunc_asinl:
2471  case LibFunc_asin:
2472  case LibFunc_asinf:
2473  case LibFunc_acosl:
2474  case LibFunc_acos:
2475  case LibFunc_acosf:
2476  return Op.compare(APFloat(Op.getSemantics(), "-1")) !=
2478  Op.compare(APFloat(Op.getSemantics(), "1")) !=
2480 
2481  case LibFunc_sinh:
2482  case LibFunc_cosh:
2483  case LibFunc_sinhf:
2484  case LibFunc_coshf:
2485  case LibFunc_sinhl:
2486  case LibFunc_coshl:
2487  // FIXME: These boundaries are slightly conservative.
2488  if (OpC->getType()->isDoubleTy())
2489  return Op.compare(APFloat(-710.0)) != APFloat::cmpLessThan &&
2490  Op.compare(APFloat(710.0)) != APFloat::cmpGreaterThan;
2491  if (OpC->getType()->isFloatTy())
2492  return Op.compare(APFloat(-89.0f)) != APFloat::cmpLessThan &&
2493  Op.compare(APFloat(89.0f)) != APFloat::cmpGreaterThan;
2494  break;
2495 
2496  case LibFunc_sqrtl:
2497  case LibFunc_sqrt:
2498  case LibFunc_sqrtf:
2499  return Op.isNaN() || Op.isZero() || !Op.isNegative();
2500 
2501  // FIXME: Add more functions: sqrt_finite, atanh, expm1, log1p,
2502  // maybe others?
2503  default:
2504  break;
2505  }
2506  }
2507  }
2508 
2509  if (Call->getNumArgOperands() == 2) {
2510  ConstantFP *Op0C = dyn_cast<ConstantFP>(Call->getArgOperand(0));
2511  ConstantFP *Op1C = dyn_cast<ConstantFP>(Call->getArgOperand(1));
2512  if (Op0C && Op1C) {
2513  const APFloat &Op0 = Op0C->getValueAPF();
2514  const APFloat &Op1 = Op1C->getValueAPF();
2515 
2516  switch (Func) {
2517  case LibFunc_powl:
2518  case LibFunc_pow:
2519  case LibFunc_powf: {
2520  // FIXME: Stop using the host math library.
2521  // FIXME: The computation isn't done in the right precision.
2522  Type *Ty = Op0C->getType();
2523  if (Ty->isDoubleTy() || Ty->isFloatTy() || Ty->isHalfTy()) {
2524  if (Ty == Op1C->getType()) {
2525  double Op0V = getValueAsDouble(Op0C);
2526  double Op1V = getValueAsDouble(Op1C);
2527  return ConstantFoldBinaryFP(pow, Op0V, Op1V, Ty) != nullptr;
2528  }
2529  }
2530  break;
2531  }
2532 
2533  case LibFunc_fmodl:
2534  case LibFunc_fmod:
2535  case LibFunc_fmodf:
2536  return Op0.isNaN() || Op1.isNaN() ||
2537  (!Op0.isInfinity() && !Op1.isZero());
2538 
2539  default:
2540  break;
2541  }
2542  }
2543  }
2544 
2545  return false;
2546 }
Constant * ConstantFoldCastOperand(unsigned Opcode, Constant *C, Type *DestTy, const DataLayout &DL)
Attempt to constant fold a cast with the specified operand.
opStatus roundToIntegral(roundingMode RM)
Definition: APFloat.h:1018
Type * getVectorElementType() const
Definition: Type.h:371
unsigned Log2(Align A)
Returns the log2 of the alignment.
Definition: Alignment.h:137
uint64_t CallInst * C
static Constant * FoldBitCast(Constant *V, Type *DestTy)
void computeKnownBits(const Value *V, KnownBits &Known, const DataLayout &DL, unsigned Depth=0, AssumptionCache *AC=nullptr, const Instruction *CxtI=nullptr, const DominatorTree *DT=nullptr, OptimizationRemarkEmitter *ORE=nullptr, bool UseInstrInfo=true)
Determine which bits of V are known to be either zero or one and return them in the KnownZero/KnownOn...
A parsed version of the target data layout string in and methods for querying it. ...
Definition: DataLayout.h:111
Definition: Any.h:26
bool isZero() const
Definition: APFloat.h:1153
bool isAllOnesValue() const
Return true if this is the value that would be returned by getAllOnesValue.
Definition: Constants.cpp:100
static IntegerType * getInt1Ty(LLVMContext &C)
Definition: Type.cpp:172
uint64_t getZExtValue() const
Get zero extended value.
Definition: APInt.h:1569
const T & back() const
back - Get the last element.
Definition: ArrayRef.h:157
MutableArrayRef< T > makeMutableArrayRef(T &OneElt)
Construct a MutableArrayRef from a single element.
Definition: ArrayRef.h:502
This class represents lattice values for constants.
Definition: AllocatorList.h:23
Constant * ConstantFoldLoadThroughGEPConstantExpr(Constant *C, ConstantExpr *CE)
ConstantFoldLoadThroughGEPConstantExpr - Given a constant and a getelementptr constantexpr, return the constant value being addressed by the constant expression, or null if something is funny and we can&#39;t decide.
static Constant * getGetElementPtr(Type *Ty, Constant *C, ArrayRef< Constant *> IdxList, bool InBounds=false, Optional< unsigned > InRangeIndex=None, Type *OnlyIfReducedTy=nullptr)
Getelementptr form.
Definition: Constants.h:1153
bool isSized(SmallPtrSetImpl< Type *> *Visited=nullptr) const
Return true if it makes sense to take the size of this type.
Definition: Type.h:264
amdgpu Simplify well known AMD library false FunctionCallee Value const Twine & Name
Function * getCaller()
Helper to get the caller (the parent function).
Constant * ConstantFoldCall(const CallBase *Call, Function *F, ArrayRef< Constant *> Operands, const TargetLibraryInfo *TLI=nullptr)
ConstantFoldCall - Attempt to constant fold a call to the specified function with the specified argum...
const StructLayout * getStructLayout(StructType *Ty) const
Returns a StructLayout object, indicating the alignment of the struct, its size, and the offsets of i...
Definition: DataLayout.cpp:610
APInt uadd_sat(const APInt &RHS) const
Definition: APInt.cpp:1971
Optional< unsigned > getInRangeIndex() const
Returns the offset of the index with an inrange attachment, or None if none.
Definition: Operator.h:463
static APInt getLowBitsSet(unsigned numBits, unsigned loBitsSet)
Get a value with low bits set.
Definition: APInt.h:647
static uint64_t round(uint64_t Acc, uint64_t Input)
Definition: xxhash.cpp:57
static Constant * getIntToPtr(Constant *C, Type *Ty, bool OnlyIfReduced=false)
Definition: Constants.cpp:1791
float convertToFloat() const
Definition: APFloat.h:1108
static Constant * getExtractElement(Constant *Vec, Constant *Idx, Type *OnlyIfReducedTy=nullptr)
Definition: Constants.cpp:2115
bool IsConstantOffsetFromGlobal(Constant *C, GlobalValue *&GV, APInt &Offset, const DataLayout &DL)
If this constant is a constant offset from a global, return the global and the constant.
LLVMContext & getContext() const
All values hold a context through their type.
Definition: Value.cpp:733
bool all_of(R &&range, UnaryPredicate P)
Provide wrappers to std::all_of which take ranges instead of having to pass begin/end explicitly...
Definition: STLExtras.h:1165
Base class for all callable instructions (InvokeInst and CallInst) Holds everything related to callin...
Definition: InstrTypes.h:1100
F(f)
const fltSemantics & getSemantics() const
Definition: APFloat.h:1165
unsigned getPointerAddressSpace() const
Get the address space of this pointer or pointer vector type.
Definition: DerivedTypes.h:580
An instruction for reading from memory.
Definition: Instructions.h:167
static IntegerType * getInt64Ty(LLVMContext &C)
Definition: Type.cpp:176
APInt zextOrTrunc(unsigned width) const
Zero extend or truncate to width.
Definition: APInt.cpp:878
static Constant * getCompare(unsigned short pred, Constant *C1, Constant *C2, bool OnlyIfReduced=false)
Return an ICmp or FCmp comparison operator constant expression.
Definition: Constants.cpp:1968
Hexagon Common GEP
static Constant * getSub(Constant *C1, Constant *C2, bool HasNUW=false, bool HasNSW=false)
Definition: Constants.cpp:2261
bool isVectorTy() const
True if this is an instance of VectorType.
Definition: Type.h:229
LLVM_READONLY APFloat maximum(const APFloat &A, const APFloat &B)
Implements IEEE 754-2018 maximum semantics.
Definition: APFloat.h:1272
static IntegerType * getInt16Ty(LLVMContext &C)
Definition: Type.cpp:174
op_iterator op_begin()
Definition: User.h:229
static APInt getSignedMaxValue(unsigned numBits)
Gets maximum signed value of APInt for a specific bit width.
Definition: APInt.h:534
unsigned getElementContainingOffset(uint64_t Offset) const
Given a valid byte offset into the structure, returns the structure index that contains it...
Definition: DataLayout.cpp:83
unsigned getBitWidth() const
Return the number of bits in the APInt.
Definition: APInt.h:1515
static Constant * getInsertElement(Constant *Vec, Constant *Elt, Constant *Idx, Type *OnlyIfReducedTy=nullptr)
Definition: Constants.cpp:2137
LLVMContext & getContext() const
Return the LLVMContext in which this type was uniqued.
Definition: Type.h:129
static Constant * getNullValue(Type *Ty)
Constructor to create a &#39;0&#39; constant of arbitrary type.
Definition: Constants.cpp:289
amode Optimize addressing mode
Value * getArgOperand(unsigned i) const
Definition: InstrTypes.h:1241
opStatus convertToInteger(MutableArrayRef< integerPart > Input, unsigned int Width, bool IsSigned, roundingMode RM, bool *IsExact) const
Definition: APFloat.h:1079
unsigned countTrailingZeros() const
Count the number of trailing zero bits.
Definition: APInt.h:1638
Used to lazily calculate structure layout information for a target machine, based on the DataLayout s...
Definition: DataLayout.h:559
bool isMathLibCallNoop(const CallBase *Call, const TargetLibraryInfo *TLI)
Check whether the given call has no side-effects.
bool isVolatile() const
Return true if this is a load from a volatile memory location.
Definition: Instructions.h:231
static Constant * getIntegerCast(Constant *C, Type *Ty, bool isSigned)
Create a ZExt, Bitcast or Trunc for integer -> integer casts.
Definition: Constants.cpp:1644
static bool castIsValid(Instruction::CastOps op, Value *S, Type *DstTy)
This method can be used to determine if a cast from S to DstTy using Opcode op is valid or not...
Type * getPointerElementType() const
Definition: Type.h:376
const DataLayout & getDataLayout() const
Get the data layout for the module&#39;s target platform.
Definition: Module.cpp:369
unsigned getPointerTypeSizeInBits(Type *) const
Layout pointer size, in bits, based on the type.
Definition: DataLayout.cpp:668
ArrayRef< T > makeArrayRef(const T &OneElt)
Construct an ArrayRef from a single element.
Definition: ArrayRef.h:450
bool isFloatingPointTy() const
Return true if this is one of the six floating-point types.
Definition: Type.h:161
APInt shl(unsigned shiftAmt) const
Left-shift function.
Definition: APInt.h:992
roundingMode
IEEE-754R 4.3: Rounding-direction attributes.
Definition: APFloat.h:184
APInt zextOrSelf(unsigned width) const
Zero extend or truncate to width.
Definition: APInt.cpp:894
A Use represents the edge between a Value definition and its users.
Definition: Use.h:55
static Constant * getLShr(Constant *C1, Constant *C2, bool isExact=false)
Definition: Constants.cpp:2328
PointerType * getPointerTo(unsigned AddrSpace=0) const
Return a pointer to the current type.
Definition: Type.cpp:654
bool isIntegerTy() const
True if this is an instance of IntegerType.
Definition: Type.h:196
LLVM_READONLY APFloat minimum(const APFloat &A, const APFloat &B)
Implements IEEE 754-2018 minimum semantics.
Definition: APFloat.h:1259
Windows NT (Windows on ARM)
iterator_range< const unsigned char * > bytes() const
Definition: StringRef.h:111
uint64_t getNumElements() const
For scalable vectors, this will return the minimum number of elements in the vector.
Definition: DerivedTypes.h:393
LLVM_NODISCARD bool empty() const
empty - Check if the string is empty.
Definition: StringRef.h:126
This file implements a class to represent arbitrary precision integral constant values and operations...
auto reverse(ContainerTy &&C, typename std::enable_if< has_rbegin< ContainerTy >::value >::type *=nullptr) -> decltype(make_range(C.rbegin(), C.rend()))
Definition: STLExtras.h:261
Constant * ConstantFoldConstant(const Constant *C, const DataLayout &DL, const TargetLibraryInfo *TLI=nullptr)
ConstantFoldConstant - Attempt to fold the constant using the specified DataLayout.
const APInt & smax(const APInt &A, const APInt &B)
Determine the larger of two APInts considered to be signed.
Definition: APInt.h:2116
const APInt & smin(const APInt &A, const APInt &B)
Determine the smaller of two APInts considered to be signed.
Definition: APInt.h:2111
static Constant * getZExt(Constant *C, Type *Ty, bool OnlyIfReduced=false)
Definition: Constants.cpp:1696
bool isNullValue() const
Return true if this is the value that would be returned by getNullValue.
Definition: Constants.cpp:85
A constant value that is initialized with an expression using other constant values.
Definition: Constants.h:888
int64_t getSExtValue() const
Get sign extended value.
Definition: APInt.h:1581
bool isInfinity() const
Definition: APFloat.h:1154
Type * getType() const
All values are typed, get the type of this value.
Definition: Value.h:245
opStatus convert(const fltSemantics &ToSemantics, roundingMode RM, bool *losesInfo)
Definition: APFloat.cpp:4483
APInt sextOrTrunc(unsigned width) const
Sign extend or truncate to width.
Definition: APInt.cpp:886
bool isInBounds() const
Test whether this is an inbounds GEP, as defined by LangRef.html.
Definition: Operator.h:457
bool has(LibFunc F) const
Tests whether a library function is available.
static Constant * getSelect(Constant *C, Constant *V1, Constant *V2, Type *OnlyIfReducedTy=nullptr)
Select constant expr.
Definition: Constants.cpp:1990
ArrayRef - Represent a constant reference to an array (0 or more elements consecutively in memory)...
Definition: APInt.h:32
LLVM_NODISCARD size_t size() const
size - Get the string size.
Definition: StringRef.h:130
bool isLittleEndian() const
Layout endianness...
Definition: DataLayout.h:233
unsigned getOpcode() const
Returns a member of one of the enums like Instruction::Add.
Definition: Instruction.h:125
static const fltSemantics & IEEEdouble() LLVM_READNONE
Definition: APFloat.cpp:158
Value * getOperand(unsigned i) const
Definition: User.h:169
Class to represent pointers.
Definition: DerivedTypes.h:544
Constant * getAggregateElement(unsigned Elt) const
For aggregates (struct/array/vector) return the constant that corresponds to the specified element if...
Definition: Constants.cpp:359
Type * getScalarType() const
If this is a vector type, return the element type, otherwise return &#39;this&#39;.
Definition: Type.h:303
static Constant * getBitCast(Constant *C, Type *Ty, bool OnlyIfReduced=false)
Definition: Constants.cpp:1804
bool isFloatTy() const
Return true if this is &#39;float&#39;, a 32-bit IEEE fp type.
Definition: Type.h:146
IntegerType * getIntPtrType(LLVMContext &C, unsigned AddressSpace=0) const
Returns an integer type with size at least as big as that of a pointer in the given address space...
Definition: DataLayout.cpp:766
static Constant * getInsertValue(Constant *Agg, Constant *Val, ArrayRef< unsigned > Idxs, Type *OnlyIfReducedTy=nullptr)
Definition: Constants.cpp:2183
bool isNegative() const
Determine sign of this APInt.
Definition: APInt.h:363
Type * getReturnType() const
Returns the type of the ret val.
Definition: Function.h:168
bool isNegative() const
Definition: APFloat.h:1157
APInt urem(const APInt &RHS) const
Unsigned remainder operation.
Definition: APInt.cpp:1617
bool hasName() const
Definition: Value.h:251
The instances of the Type class are immutable: once they are created, they are never changed...
Definition: Type.h:45
std::error_code status(const Twine &path, file_status &result, bool follow=true)
Get file status as if by POSIX stat().
bool isNoBuiltin() const
Return true if the call should not be treated as a call to a builtin.
Definition: InstrTypes.h:1611
size_t size() const
size - Get the array size.
Definition: ArrayRef.h:148
bool isNaN() const
Definition: APFloat.h:1155
static GCRegistry::Add< CoreCLRGC > E("coreclr", "CoreCLR-compatible GC")
This is an important base class in LLVM.
Definition: Constant.h:41
const APInt & getConstant() const
Returns the value when all bits have a known value.
Definition: KnownBits.h:56
This file contains the declarations for the subclasses of Constant, which represent the different fla...
bool isPointerTy() const
True if this is an instance of PointerType.
Definition: Type.h:223
static Constant * getAnd(Constant *C1, Constant *C2)
Definition: Constants.cpp:2309
ConstantFP - Floating Point Values [float, double].
Definition: Constants.h:263
bool isOneValue() const
Determine if this is a value of 1.
Definition: APInt.h:410
APInt ssub_ov(const APInt &RHS, bool &Overflow) const
Definition: APInt.cpp:1892
Constant * ConstantFoldInstruction(Instruction *I, const DataLayout &DL, const TargetLibraryInfo *TLI=nullptr)
ConstantFoldInstruction - Try to constant fold the specified instruction.
double convertToDouble() const
Definition: APFloat.h:1107
static Constant * getShuffleVector(Constant *V1, Constant *V2, Constant *Mask, Type *OnlyIfReducedTy=nullptr)
Definition: Constants.cpp:2160
op_iterator op_end()
Definition: User.h:231
This file declares a class to represent arbitrary precision floating point values and provide a varie...
bool isHalfTy() const
Return true if this is &#39;half&#39;, a 16-bit IEEE fp type.
Definition: Type.h:143
bool isConstant() const
Returns true if we know the value of all bits.
Definition: KnownBits.h:49
Predicate
This enumeration lists the possible predicates for CmpInst subclasses.
Definition: InstrTypes.h:732
bool isBinaryOp() const
Definition: Instruction.h:130
static Constant * get(StructType *T, ArrayRef< Constant *> V)
Definition: Constants.cpp:1075
op_range operands()
Definition: User.h:237
bool isX86_MMXTy() const
Return true if this is X86 MMX.
Definition: Type.h:181
Class to represent integer types.
Definition: DerivedTypes.h:40
unsigned getIndexTypeSizeInBits(Type *Ty) const
Layout size of the index used in GEP calculation.
Definition: DataLayout.cpp:684
Constant * ConstantFoldLoadFromConstPtr(Constant *C, Type *Ty, const DataLayout &DL)
ConstantFoldLoadFromConstPtr - Return the value that a load from C would produce if it is constant an...
static double log2(double V)
static Constant * getAllOnesValue(Type *Ty)
Definition: Constants.cpp:343
static UndefValue * get(Type *T)
Static factory methods - Return an &#39;undef&#39; object of the specified type.
Definition: Constants.cpp:1446
bool isCast() const
Definition: Instruction.h:133
size_t size() const
Definition: SmallVector.h:52
Constant * ConstantFoldLoadThroughGEPIndices(Constant *C, ArrayRef< Constant *> Indices)
ConstantFoldLoadThroughGEPIndices - Given a constant and getelementptr indices (with an implied zero ...
static wasm::ValType getType(const TargetRegisterClass *RC)
APInt uadd_ov(const APInt &RHS, bool &Overflow) const
Definition: APInt.cpp:1886
Constant * ConstantFoldCompareInstOperands(unsigned Predicate, Constant *LHS, Constant *RHS, const DataLayout &DL, const TargetLibraryInfo *TLI=nullptr)
ConstantFoldCompareInstOperands - Attempt to constant fold a compare instruction (icmp/fcmp) with the...
Value * GetUnderlyingObject(Value *V, const DataLayout &DL, unsigned MaxLookup=6)
This method strips off any GEP address adjustments and pointer casts from the specified value...
APInt ssub_sat(const APInt &RHS) const
Definition: APInt.cpp:1980
#define llvm_unreachable(msg)
Marks that the current location is not supposed to be reachable.
void copySign(const APFloat &RHS)
Definition: APFloat.h:1065
LLVM_READONLY APFloat maxnum(const APFloat &A, const APFloat &B)
Implements IEEE maxNum semantics.
Definition: APFloat.h:1248
const T * data() const
Definition: ArrayRef.h:145
APInt lshr(unsigned shiftAmt) const
Logical right-shift function.
Definition: APInt.h:970
bool canConstantFoldCallTo(const CallBase *Call, const Function *F)
canConstantFoldCallTo - Return true if its even possible to fold a call to the specified function...
const APFloat & getValueAPF() const
Definition: Constants.h:302
static Constant * getPointerCast(Constant *C, Type *Ty)
Create a BitCast, AddrSpaceCast, or a PtrToInt cast constant expression.
Definition: Constants.cpp:1618
bool isPtrOrPtrVectorTy() const
Return true if this is a pointer type or a vector of pointer types.
Definition: Type.h:226
static IntegerType * get(LLVMContext &C, unsigned NumBits)
This static method is the primary way of constructing an IntegerType.
Definition: Type.cpp:239
Type * getSequentialElementType() const
Definition: Type.h:357
unsigned getNumOperands() const
Definition: User.h:191
This is the shared class of boolean and integer constants.
Definition: Constants.h:83
static const fltSemantics & IEEEhalf() LLVM_READNONE
Definition: APFloat.cpp:152
unsigned getScalarSizeInBits() const LLVM_READONLY
If this is a vector type, return the getPrimitiveSizeInBits value for the element type...
Definition: Type.cpp:129
This is a &#39;vector&#39; (really, a variable-sized array), optimized for the case when the array is small...
Definition: SmallVector.h:837
Provides information about what library functions are available for the current target.
bool isAggregateType() const
Return true if the type is an aggregate type.
Definition: Type.h:257
static IntegerType * getIntNTy(LLVMContext &C, unsigned N)
Definition: Type.cpp:179
static Constant * getTrunc(Constant *C, Type *Ty, bool OnlyIfReduced=false)
Definition: Constants.cpp:1668
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:653
static Constant * get(Type *Ty, double V)
This returns a ConstantFP, or a vector containing a splat of a ConstantFP, for the specified value in...
Definition: Constants.cpp:716
bool hasVectorInstrinsicScalarOpd(Intrinsic::ID ID, unsigned ScalarOpdIdx)
Identifies if the vector form of the intrinsic has a scalar operand.
Definition: VectorUtils.cpp:91
bool uge(const APInt &RHS) const
Unsigned greater or equal comparison.
Definition: APInt.h:1292
bool NullPointerIsDefined(const Function *F, unsigned AS=0)
Check whether null pointer dereferencing is considered undefined behavior for a given function or an ...
Definition: Function.cpp:1523
static ConstantInt * getTrue(LLVMContext &Context)
Definition: Constants.cpp:609
Intrinsic::ID getIntrinsicID() const LLVM_READONLY
getIntrinsicID - This method returns the ID number of the specified function, or Intrinsic::not_intri...
Definition: Function.h:193
unsigned getVectorNumElements() const
Definition: DerivedTypes.h:535
Class to represent vector types.
Definition: DerivedTypes.h:427
Class for arbitrary precision integers.
Definition: APInt.h:69
static Constant * getCast(unsigned ops, Constant *C, Type *Ty, bool OnlyIfReduced=false)
Convenience function for getting a Cast operation.
Definition: Constants.cpp:1561
Type * getResultElementType() const
Definition: Operator.cpp:28
bool getLibFunc(StringRef funcName, LibFunc &F) const
Searches for a particular function name.
ArrayRef< T > slice(size_t N, size_t M) const
slice(n, m) - Chop off the first N elements of the array, and keep M elements in the array...
Definition: ArrayRef.h:178
void append(in_iter in_start, in_iter in_end)
Add the specified range to the end of the SmallVector.
Definition: SmallVector.h:387
bool isNonIntegralPointerType(PointerType *PT) const
Definition: DataLayout.h:377
uint64_t getTypeSizeInBits(Type *Ty) const
Size examples:
Definition: DataLayout.h:598
uint64_t getTypeAllocSize(Type *Ty) const
Returns the offset in bytes between successive objects of the specified type, including alignment pad...
Definition: DataLayout.h:470
opStatus
IEEE-754R 7: Default exception handling.
Definition: APFloat.h:195
unsigned getNumArgOperands() const
Definition: InstrTypes.h:1239
uint64_t getElementOffset(unsigned Idx) const
Definition: DataLayout.h:581
static Type * getIndexedType(Type *Ty, ArrayRef< Value *> IdxList)
Returns the type of the element that would be loaded with a load instruction with the specified param...
static IntegerType * getInt32Ty(LLVMContext &C)
Definition: Type.cpp:175
unsigned getIntegerBitWidth() const
Definition: DerivedTypes.h:97
LLVM_NODISCARD bool empty() const
Definition: SmallVector.h:55
static VectorType * get(Type *ElementType, ElementCount EC)
This static method is the primary way to construct an VectorType.
Definition: Type.cpp:609
StringRef getName() const
Return a constant reference to the value&#39;s name.
Definition: Value.cpp:214
Function * getCalledFunction() const
Returns the function called, or null if this is an indirect function invocation.
Definition: InstrTypes.h:1287
APInt smul_ov(const APInt &RHS, bool &Overflow) const
Definition: APInt.cpp:1911
static Instruction::CastOps getCastOpcode(const Value *Val, bool SrcIsSigned, Type *Ty, bool DstIsSigned)
Returns the opcode necessary to cast Val into Ty using usual casting rules.
static Constant * getPtrToInt(Constant *C, Type *Ty, bool OnlyIfReduced=false)
Definition: Constants.cpp:1778
#define I(x, y, z)
Definition: MD5.cpp:58
static Constant * getOr(Constant *C1, Constant *C2)
Definition: Constants.cpp:2313
Constant * ConstantFoldUnaryOpOperand(unsigned Opcode, Constant *Op, const DataLayout &DL)
Attempt to constant fold a unary operation with the specified operand.
iterator_range< value_op_iterator > operand_values()
Definition: User.h:261
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:332
Constant * ConstantFoldInstOperands(Instruction *I, ArrayRef< Constant *> Ops, const DataLayout &DL, const TargetLibraryInfo *TLI=nullptr)
ConstantFoldInstOperands - Attempt to constant fold an instruction with the specified operands...
static Constant * getShl(Constant *C1, Constant *C2, bool HasNUW=false, bool HasNSW=false)
Definition: Constants.cpp:2321
bool isStrictFP() const
Determine if the call requires strict floating point semantics.
Definition: InstrTypes.h:1617
APInt umul_ov(const APInt &RHS, bool &Overflow) const
Definition: APInt.cpp:1921
bool getConstantStringInfo(const Value *V, StringRef &Str, uint64_t Offset=0, bool TrimAtNul=true)
This function computes the length of a null-terminated C string pointed to by V.
assert(ImpDefSCC.getReg()==AMDGPU::SCC &&ImpDefSCC.isDef())
opStatus fusedMultiplyAdd(const APFloat &Multiplicand, const APFloat &Addend, roundingMode RM)
Definition: APFloat.h:1005
static APInt getSignedMinValue(unsigned numBits)
Gets minimum signed value of APInt for a specific bit width.
Definition: APInt.h:544
APInt sadd_ov(const APInt &RHS, bool &Overflow) const
Definition: APInt.cpp:1879
unsigned getPrimitiveSizeInBits() const LLVM_READONLY
Return the basic size of this type if it is a primitive type.
Definition: Type.cpp:114
Module * getParent()
Get the module that this global value is contained inside of...
Definition: GlobalValue.h:575
LLVM Value Representation.
Definition: Value.h:73
Constant * ConstantFoldLoadThroughBitcast(Constant *C, Type *DestTy, const DataLayout &DL)
ConstantFoldLoadThroughBitcast - try to cast constant to destination type returning null if unsuccess...
#define LLVM_FALLTHROUGH
LLVM_FALLTHROUGH - Mark fallthrough cases in switch statements.
Definition: Compiler.h:265
std::underlying_type< E >::type Mask()
Get a bitmask with 1s in all places up to the high-order bit of E&#39;s largest value.
Definition: BitmaskEnum.h:80
Type * getElementType() const
Definition: DerivedTypes.h:394
APInt usub_sat(const APInt &RHS) const
Definition: APInt.cpp:1990
static Constant * getExtractValue(Constant *Agg, ArrayRef< unsigned > Idxs, Type *OnlyIfReducedTy=nullptr)
Definition: Constants.cpp:2207
StringRef - Represent a constant reference to a string, i.e.
Definition: StringRef.h:48
Predicate getSwappedPredicate() const
For example, EQ->EQ, SLE->SGE, ULT->UGT, OEQ->OEQ, ULE->UGE, OLT->OGT, etc.
Definition: InstrTypes.h:847
Type * getSourceElementType() const
Definition: Operator.cpp:22
APInt bitcastToAPInt() const
Definition: APFloat.h:1104
unsigned countLeadingZeros() const
The APInt version of the countLeadingZeros functions in MathExtras.h.
Definition: APInt.h:1602
APInt sadd_sat(const APInt &RHS) const
Definition: APInt.cpp:1961
bool isDoubleTy() const
Return true if this is &#39;double&#39;, a 64-bit IEEE fp type.
Definition: Type.h:149
bool isUnaryOp() const
Definition: Instruction.h:129
static Constant * get(ArrayRef< Constant *> V)
Definition: Constants.cpp:1110
APInt sextOrSelf(unsigned width) const
Sign extend or truncate to width.
Definition: APInt.cpp:900
LLVM_READONLY APFloat minnum(const APFloat &A, const APFloat &B)
Implements IEEE minNum semantics.
Definition: APFloat.h:1237
int64_t getIndexedOffsetInType(Type *ElemTy, ArrayRef< Value *> Indices) const
Returns the offset from the beginning of the type for the specified indices.
Definition: DataLayout.cpp:803
PointerType * getType() const
Global values are always pointers.
Definition: GlobalValue.h:277
bool isNullValue() const
Determine if all bits are clear.
Definition: APInt.h:405
bool isStructTy() const
True if this is an instance of StructType.
Definition: Type.h:217
cmpResult compare(const APFloat &RHS) const
Definition: APFloat.h:1112
const BasicBlock * getParent() const
Definition: Instruction.h:66
APInt sdiv_ov(const APInt &RHS, bool &Overflow) const
Definition: APInt.cpp:1905
const fltSemantics & getFltSemantics() const
Definition: Type.h:168
APInt usub_ov(const APInt &RHS, bool &Overflow) const
Definition: APInt.cpp:1899
static Constant * get(unsigned Opcode, Constant *C1, unsigned Flags=0, Type *OnlyIfReducedTy=nullptr)
get - Return a unary operator constant expression, folding if possible.
Definition: Constants.cpp:1837
Constant * ConstantFoldBinaryOpOperands(unsigned Opcode, Constant *LHS, Constant *RHS, const DataLayout &DL)
Attempt to constant fold a binary operation with the specified operands.