clang  10.0.0git
CGExprConstant.cpp
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1 //===--- CGExprConstant.cpp - Emit LLVM Code from Constant Expressions ----===//
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 contains code to emit Constant Expr nodes as LLVM code.
10 //
11 //===----------------------------------------------------------------------===//
12 
13 #include "CGCXXABI.h"
14 #include "CGObjCRuntime.h"
15 #include "CGRecordLayout.h"
16 #include "CodeGenFunction.h"
17 #include "CodeGenModule.h"
18 #include "ConstantEmitter.h"
19 #include "TargetInfo.h"
20 #include "clang/AST/APValue.h"
21 #include "clang/AST/ASTContext.h"
22 #include "clang/AST/Attr.h"
23 #include "clang/AST/RecordLayout.h"
24 #include "clang/AST/StmtVisitor.h"
25 #include "clang/Basic/Builtins.h"
26 #include "llvm/ADT/STLExtras.h"
27 #include "llvm/ADT/Sequence.h"
28 #include "llvm/IR/Constants.h"
29 #include "llvm/IR/DataLayout.h"
30 #include "llvm/IR/Function.h"
31 #include "llvm/IR/GlobalVariable.h"
32 using namespace clang;
33 using namespace CodeGen;
34 
35 //===----------------------------------------------------------------------===//
36 // ConstantAggregateBuilder
37 //===----------------------------------------------------------------------===//
38 
39 namespace {
40 class ConstExprEmitter;
41 
42 struct ConstantAggregateBuilderUtils {
43  CodeGenModule &CGM;
44 
45  ConstantAggregateBuilderUtils(CodeGenModule &CGM) : CGM(CGM) {}
46 
47  CharUnits getAlignment(const llvm::Constant *C) const {
49  CGM.getDataLayout().getABITypeAlignment(C->getType()));
50  }
51 
52  CharUnits getSize(llvm::Type *Ty) const {
53  return CharUnits::fromQuantity(CGM.getDataLayout().getTypeAllocSize(Ty));
54  }
55 
56  CharUnits getSize(const llvm::Constant *C) const {
57  return getSize(C->getType());
58  }
59 
60  llvm::Constant *getPadding(CharUnits PadSize) const {
61  llvm::Type *Ty = CGM.Int8Ty;
62  if (PadSize > CharUnits::One())
63  Ty = llvm::ArrayType::get(Ty, PadSize.getQuantity());
64  return llvm::UndefValue::get(Ty);
65  }
66 
67  llvm::Constant *getZeroes(CharUnits ZeroSize) const {
68  llvm::Type *Ty = llvm::ArrayType::get(CGM.Int8Ty, ZeroSize.getQuantity());
69  return llvm::ConstantAggregateZero::get(Ty);
70  }
71 };
72 
73 /// Incremental builder for an llvm::Constant* holding a struct or array
74 /// constant.
75 class ConstantAggregateBuilder : private ConstantAggregateBuilderUtils {
76  /// The elements of the constant. These two arrays must have the same size;
77  /// Offsets[i] describes the offset of Elems[i] within the constant. The
78  /// elements are kept in increasing offset order, and we ensure that there
79  /// is no overlap: Offsets[i+1] >= Offsets[i] + getSize(Elemes[i]).
80  ///
81  /// This may contain explicit padding elements (in order to create a
82  /// natural layout), but need not. Gaps between elements are implicitly
83  /// considered to be filled with undef.
86 
87  /// The size of the constant (the maximum end offset of any added element).
88  /// May be larger than the end of Elems.back() if we split the last element
89  /// and removed some trailing undefs.
90  CharUnits Size = CharUnits::Zero();
91 
92  /// This is true only if laying out Elems in order as the elements of a
93  /// non-packed LLVM struct will give the correct layout.
94  bool NaturalLayout = true;
95 
96  bool split(size_t Index, CharUnits Hint);
97  Optional<size_t> splitAt(CharUnits Pos);
98 
99  static llvm::Constant *buildFrom(CodeGenModule &CGM,
101  ArrayRef<CharUnits> Offsets,
102  CharUnits StartOffset, CharUnits Size,
103  bool NaturalLayout, llvm::Type *DesiredTy,
104  bool AllowOversized);
105 
106 public:
107  ConstantAggregateBuilder(CodeGenModule &CGM)
108  : ConstantAggregateBuilderUtils(CGM) {}
109 
110  /// Update or overwrite the value starting at \p Offset with \c C.
111  ///
112  /// \param AllowOverwrite If \c true, this constant might overwrite (part of)
113  /// a constant that has already been added. This flag is only used to
114  /// detect bugs.
115  bool add(llvm::Constant *C, CharUnits Offset, bool AllowOverwrite);
116 
117  /// Update or overwrite the bits starting at \p OffsetInBits with \p Bits.
118  bool addBits(llvm::APInt Bits, uint64_t OffsetInBits, bool AllowOverwrite);
119 
120  /// Attempt to condense the value starting at \p Offset to a constant of type
121  /// \p DesiredTy.
122  void condense(CharUnits Offset, llvm::Type *DesiredTy);
123 
124  /// Produce a constant representing the entire accumulated value, ideally of
125  /// the specified type. If \p AllowOversized, the constant might be larger
126  /// than implied by \p DesiredTy (eg, if there is a flexible array member).
127  /// Otherwise, the constant will be of exactly the same size as \p DesiredTy
128  /// even if we can't represent it as that type.
129  llvm::Constant *build(llvm::Type *DesiredTy, bool AllowOversized) const {
130  return buildFrom(CGM, Elems, Offsets, CharUnits::Zero(), Size,
131  NaturalLayout, DesiredTy, AllowOversized);
132  }
133 };
134 
135 template<typename Container, typename Range = std::initializer_list<
136  typename Container::value_type>>
137 static void replace(Container &C, size_t BeginOff, size_t EndOff, Range Vals) {
138  assert(BeginOff <= EndOff && "invalid replacement range");
139  llvm::replace(C, C.begin() + BeginOff, C.begin() + EndOff, Vals);
140 }
141 
142 bool ConstantAggregateBuilder::add(llvm::Constant *C, CharUnits Offset,
143  bool AllowOverwrite) {
144  // Common case: appending to a layout.
145  if (Offset >= Size) {
146  CharUnits Align = getAlignment(C);
147  CharUnits AlignedSize = Size.alignTo(Align);
148  if (AlignedSize > Offset || Offset.alignTo(Align) != Offset)
149  NaturalLayout = false;
150  else if (AlignedSize < Offset) {
151  Elems.push_back(getPadding(Offset - Size));
152  Offsets.push_back(Size);
153  }
154  Elems.push_back(C);
155  Offsets.push_back(Offset);
156  Size = Offset + getSize(C);
157  return true;
158  }
159 
160  // Uncommon case: constant overlaps what we've already created.
161  llvm::Optional<size_t> FirstElemToReplace = splitAt(Offset);
162  if (!FirstElemToReplace)
163  return false;
164 
165  CharUnits CSize = getSize(C);
166  llvm::Optional<size_t> LastElemToReplace = splitAt(Offset + CSize);
167  if (!LastElemToReplace)
168  return false;
169 
170  assert((FirstElemToReplace == LastElemToReplace || AllowOverwrite) &&
171  "unexpectedly overwriting field");
172 
173  replace(Elems, *FirstElemToReplace, *LastElemToReplace, {C});
174  replace(Offsets, *FirstElemToReplace, *LastElemToReplace, {Offset});
175  Size = std::max(Size, Offset + CSize);
176  NaturalLayout = false;
177  return true;
178 }
179 
180 bool ConstantAggregateBuilder::addBits(llvm::APInt Bits, uint64_t OffsetInBits,
181  bool AllowOverwrite) {
182  const ASTContext &Context = CGM.getContext();
183  const uint64_t CharWidth = CGM.getContext().getCharWidth();
184 
185  // Offset of where we want the first bit to go within the bits of the
186  // current char.
187  unsigned OffsetWithinChar = OffsetInBits % CharWidth;
188 
189  // We split bit-fields up into individual bytes. Walk over the bytes and
190  // update them.
191  for (CharUnits OffsetInChars =
192  Context.toCharUnitsFromBits(OffsetInBits - OffsetWithinChar);
193  /**/; ++OffsetInChars) {
194  // Number of bits we want to fill in this char.
195  unsigned WantedBits =
196  std::min((uint64_t)Bits.getBitWidth(), CharWidth - OffsetWithinChar);
197 
198  // Get a char containing the bits we want in the right places. The other
199  // bits have unspecified values.
200  llvm::APInt BitsThisChar = Bits;
201  if (BitsThisChar.getBitWidth() < CharWidth)
202  BitsThisChar = BitsThisChar.zext(CharWidth);
203  if (CGM.getDataLayout().isBigEndian()) {
204  // Figure out how much to shift by. We may need to left-shift if we have
205  // less than one byte of Bits left.
206  int Shift = Bits.getBitWidth() - CharWidth + OffsetWithinChar;
207  if (Shift > 0)
208  BitsThisChar.lshrInPlace(Shift);
209  else if (Shift < 0)
210  BitsThisChar = BitsThisChar.shl(-Shift);
211  } else {
212  BitsThisChar = BitsThisChar.shl(OffsetWithinChar);
213  }
214  if (BitsThisChar.getBitWidth() > CharWidth)
215  BitsThisChar = BitsThisChar.trunc(CharWidth);
216 
217  if (WantedBits == CharWidth) {
218  // Got a full byte: just add it directly.
219  add(llvm::ConstantInt::get(CGM.getLLVMContext(), BitsThisChar),
220  OffsetInChars, AllowOverwrite);
221  } else {
222  // Partial byte: update the existing integer if there is one. If we
223  // can't split out a 1-CharUnit range to update, then we can't add
224  // these bits and fail the entire constant emission.
225  llvm::Optional<size_t> FirstElemToUpdate = splitAt(OffsetInChars);
226  if (!FirstElemToUpdate)
227  return false;
228  llvm::Optional<size_t> LastElemToUpdate =
229  splitAt(OffsetInChars + CharUnits::One());
230  if (!LastElemToUpdate)
231  return false;
232  assert(*LastElemToUpdate - *FirstElemToUpdate < 2 &&
233  "should have at most one element covering one byte");
234 
235  // Figure out which bits we want and discard the rest.
236  llvm::APInt UpdateMask(CharWidth, 0);
237  if (CGM.getDataLayout().isBigEndian())
238  UpdateMask.setBits(CharWidth - OffsetWithinChar - WantedBits,
239  CharWidth - OffsetWithinChar);
240  else
241  UpdateMask.setBits(OffsetWithinChar, OffsetWithinChar + WantedBits);
242  BitsThisChar &= UpdateMask;
243 
244  if (*FirstElemToUpdate == *LastElemToUpdate ||
245  Elems[*FirstElemToUpdate]->isNullValue() ||
246  isa<llvm::UndefValue>(Elems[*FirstElemToUpdate])) {
247  // All existing bits are either zero or undef.
248  add(llvm::ConstantInt::get(CGM.getLLVMContext(), BitsThisChar),
249  OffsetInChars, /*AllowOverwrite*/ true);
250  } else {
251  llvm::Constant *&ToUpdate = Elems[*FirstElemToUpdate];
252  // In order to perform a partial update, we need the existing bitwise
253  // value, which we can only extract for a constant int.
254  auto *CI = dyn_cast<llvm::ConstantInt>(ToUpdate);
255  if (!CI)
256  return false;
257  // Because this is a 1-CharUnit range, the constant occupying it must
258  // be exactly one CharUnit wide.
259  assert(CI->getBitWidth() == CharWidth && "splitAt failed");
260  assert((!(CI->getValue() & UpdateMask) || AllowOverwrite) &&
261  "unexpectedly overwriting bitfield");
262  BitsThisChar |= (CI->getValue() & ~UpdateMask);
263  ToUpdate = llvm::ConstantInt::get(CGM.getLLVMContext(), BitsThisChar);
264  }
265  }
266 
267  // Stop if we've added all the bits.
268  if (WantedBits == Bits.getBitWidth())
269  break;
270 
271  // Remove the consumed bits from Bits.
272  if (!CGM.getDataLayout().isBigEndian())
273  Bits.lshrInPlace(WantedBits);
274  Bits = Bits.trunc(Bits.getBitWidth() - WantedBits);
275 
276  // The remanining bits go at the start of the following bytes.
277  OffsetWithinChar = 0;
278  }
279 
280  return true;
281 }
282 
283 /// Returns a position within Elems and Offsets such that all elements
284 /// before the returned index end before Pos and all elements at or after
285 /// the returned index begin at or after Pos. Splits elements as necessary
286 /// to ensure this. Returns None if we find something we can't split.
287 Optional<size_t> ConstantAggregateBuilder::splitAt(CharUnits Pos) {
288  if (Pos >= Size)
289  return Offsets.size();
290 
291  while (true) {
292  auto FirstAfterPos = llvm::upper_bound(Offsets, Pos);
293  if (FirstAfterPos == Offsets.begin())
294  return 0;
295 
296  // If we already have an element starting at Pos, we're done.
297  size_t LastAtOrBeforePosIndex = FirstAfterPos - Offsets.begin() - 1;
298  if (Offsets[LastAtOrBeforePosIndex] == Pos)
299  return LastAtOrBeforePosIndex;
300 
301  // We found an element starting before Pos. Check for overlap.
302  if (Offsets[LastAtOrBeforePosIndex] +
303  getSize(Elems[LastAtOrBeforePosIndex]) <= Pos)
304  return LastAtOrBeforePosIndex + 1;
305 
306  // Try to decompose it into smaller constants.
307  if (!split(LastAtOrBeforePosIndex, Pos))
308  return None;
309  }
310 }
311 
312 /// Split the constant at index Index, if possible. Return true if we did.
313 /// Hint indicates the location at which we'd like to split, but may be
314 /// ignored.
315 bool ConstantAggregateBuilder::split(size_t Index, CharUnits Hint) {
316  NaturalLayout = false;
317  llvm::Constant *C = Elems[Index];
318  CharUnits Offset = Offsets[Index];
319 
320  if (auto *CA = dyn_cast<llvm::ConstantAggregate>(C)) {
321  replace(Elems, Index, Index + 1,
322  llvm::map_range(llvm::seq(0u, CA->getNumOperands()),
323  [&](unsigned Op) { return CA->getOperand(Op); }));
324  if (auto *Seq = dyn_cast<llvm::SequentialType>(CA->getType())) {
325  // Array or vector.
326  CharUnits ElemSize = getSize(Seq->getElementType());
327  replace(
328  Offsets, Index, Index + 1,
329  llvm::map_range(llvm::seq(0u, CA->getNumOperands()),
330  [&](unsigned Op) { return Offset + Op * ElemSize; }));
331  } else {
332  // Must be a struct.
333  auto *ST = cast<llvm::StructType>(CA->getType());
334  const llvm::StructLayout *Layout =
335  CGM.getDataLayout().getStructLayout(ST);
336  replace(Offsets, Index, Index + 1,
337  llvm::map_range(
338  llvm::seq(0u, CA->getNumOperands()), [&](unsigned Op) {
339  return Offset + CharUnits::fromQuantity(
340  Layout->getElementOffset(Op));
341  }));
342  }
343  return true;
344  }
345 
346  if (auto *CDS = dyn_cast<llvm::ConstantDataSequential>(C)) {
347  // FIXME: If possible, split into two ConstantDataSequentials at Hint.
348  CharUnits ElemSize = getSize(CDS->getElementType());
349  replace(Elems, Index, Index + 1,
350  llvm::map_range(llvm::seq(0u, CDS->getNumElements()),
351  [&](unsigned Elem) {
352  return CDS->getElementAsConstant(Elem);
353  }));
354  replace(Offsets, Index, Index + 1,
355  llvm::map_range(
356  llvm::seq(0u, CDS->getNumElements()),
357  [&](unsigned Elem) { return Offset + Elem * ElemSize; }));
358  return true;
359  }
360 
361  if (isa<llvm::ConstantAggregateZero>(C)) {
362  CharUnits ElemSize = getSize(C);
363  assert(Hint > Offset && Hint < Offset + ElemSize && "nothing to split");
364  replace(Elems, Index, Index + 1,
365  {getZeroes(Hint - Offset), getZeroes(Offset + ElemSize - Hint)});
366  replace(Offsets, Index, Index + 1, {Offset, Hint});
367  return true;
368  }
369 
370  if (isa<llvm::UndefValue>(C)) {
371  replace(Elems, Index, Index + 1, {});
372  replace(Offsets, Index, Index + 1, {});
373  return true;
374  }
375 
376  // FIXME: We could split a ConstantInt if the need ever arose.
377  // We don't need to do this to handle bit-fields because we always eagerly
378  // split them into 1-byte chunks.
379 
380  return false;
381 }
382 
383 static llvm::Constant *
384 EmitArrayConstant(CodeGenModule &CGM, llvm::ArrayType *DesiredType,
385  llvm::Type *CommonElementType, unsigned ArrayBound,
387  llvm::Constant *Filler);
388 
389 llvm::Constant *ConstantAggregateBuilder::buildFrom(
391  ArrayRef<CharUnits> Offsets, CharUnits StartOffset, CharUnits Size,
392  bool NaturalLayout, llvm::Type *DesiredTy, bool AllowOversized) {
393  ConstantAggregateBuilderUtils Utils(CGM);
394 
395  if (Elems.empty())
396  return llvm::UndefValue::get(DesiredTy);
397 
398  auto Offset = [&](size_t I) { return Offsets[I] - StartOffset; };
399 
400  // If we want an array type, see if all the elements are the same type and
401  // appropriately spaced.
402  if (llvm::ArrayType *ATy = dyn_cast<llvm::ArrayType>(DesiredTy)) {
403  assert(!AllowOversized && "oversized array emission not supported");
404 
405  bool CanEmitArray = true;
406  llvm::Type *CommonType = Elems[0]->getType();
407  llvm::Constant *Filler = llvm::Constant::getNullValue(CommonType);
408  CharUnits ElemSize = Utils.getSize(ATy->getElementType());
409  SmallVector<llvm::Constant*, 32> ArrayElements;
410  for (size_t I = 0; I != Elems.size(); ++I) {
411  // Skip zeroes; we'll use a zero value as our array filler.
412  if (Elems[I]->isNullValue())
413  continue;
414 
415  // All remaining elements must be the same type.
416  if (Elems[I]->getType() != CommonType ||
417  Offset(I) % ElemSize != 0) {
418  CanEmitArray = false;
419  break;
420  }
421  ArrayElements.resize(Offset(I) / ElemSize + 1, Filler);
422  ArrayElements.back() = Elems[I];
423  }
424 
425  if (CanEmitArray) {
426  return EmitArrayConstant(CGM, ATy, CommonType, ATy->getNumElements(),
427  ArrayElements, Filler);
428  }
429 
430  // Can't emit as an array, carry on to emit as a struct.
431  }
432 
433  CharUnits DesiredSize = Utils.getSize(DesiredTy);
434  CharUnits Align = CharUnits::One();
435  for (llvm::Constant *C : Elems)
436  Align = std::max(Align, Utils.getAlignment(C));
437  CharUnits AlignedSize = Size.alignTo(Align);
438 
439  bool Packed = false;
440  ArrayRef<llvm::Constant*> UnpackedElems = Elems;
441  llvm::SmallVector<llvm::Constant*, 32> UnpackedElemStorage;
442  if ((DesiredSize < AlignedSize && !AllowOversized) ||
443  DesiredSize.alignTo(Align) != DesiredSize) {
444  // The natural layout would be the wrong size; force use of a packed layout.
445  NaturalLayout = false;
446  Packed = true;
447  } else if (DesiredSize > AlignedSize) {
448  // The constant would be too small. Add padding to fix it.
449  UnpackedElemStorage.assign(Elems.begin(), Elems.end());
450  UnpackedElemStorage.push_back(Utils.getPadding(DesiredSize - Size));
451  UnpackedElems = UnpackedElemStorage;
452  }
453 
454  // If we don't have a natural layout, insert padding as necessary.
455  // As we go, double-check to see if we can actually just emit Elems
456  // as a non-packed struct and do so opportunistically if possible.
458  if (!NaturalLayout) {
459  CharUnits SizeSoFar = CharUnits::Zero();
460  for (size_t I = 0; I != Elems.size(); ++I) {
461  CharUnits Align = Utils.getAlignment(Elems[I]);
462  CharUnits NaturalOffset = SizeSoFar.alignTo(Align);
463  CharUnits DesiredOffset = Offset(I);
464  assert(DesiredOffset >= SizeSoFar && "elements out of order");
465 
466  if (DesiredOffset != NaturalOffset)
467  Packed = true;
468  if (DesiredOffset != SizeSoFar)
469  PackedElems.push_back(Utils.getPadding(DesiredOffset - SizeSoFar));
470  PackedElems.push_back(Elems[I]);
471  SizeSoFar = DesiredOffset + Utils.getSize(Elems[I]);
472  }
473  // If we're using the packed layout, pad it out to the desired size if
474  // necessary.
475  if (Packed) {
476  assert((SizeSoFar <= DesiredSize || AllowOversized) &&
477  "requested size is too small for contents");
478  if (SizeSoFar < DesiredSize)
479  PackedElems.push_back(Utils.getPadding(DesiredSize - SizeSoFar));
480  }
481  }
482 
483  llvm::StructType *STy = llvm::ConstantStruct::getTypeForElements(
484  CGM.getLLVMContext(), Packed ? PackedElems : UnpackedElems, Packed);
485 
486  // Pick the type to use. If the type is layout identical to the desired
487  // type then use it, otherwise use whatever the builder produced for us.
488  if (llvm::StructType *DesiredSTy = dyn_cast<llvm::StructType>(DesiredTy)) {
489  if (DesiredSTy->isLayoutIdentical(STy))
490  STy = DesiredSTy;
491  }
492 
493  return llvm::ConstantStruct::get(STy, Packed ? PackedElems : UnpackedElems);
494 }
495 
496 void ConstantAggregateBuilder::condense(CharUnits Offset,
497  llvm::Type *DesiredTy) {
498  CharUnits Size = getSize(DesiredTy);
499 
500  llvm::Optional<size_t> FirstElemToReplace = splitAt(Offset);
501  if (!FirstElemToReplace)
502  return;
503  size_t First = *FirstElemToReplace;
504 
505  llvm::Optional<size_t> LastElemToReplace = splitAt(Offset + Size);
506  if (!LastElemToReplace)
507  return;
508  size_t Last = *LastElemToReplace;
509 
510  size_t Length = Last - First;
511  if (Length == 0)
512  return;
513 
514  if (Length == 1 && Offsets[First] == Offset &&
515  getSize(Elems[First]) == Size) {
516  // Re-wrap single element structs if necessary. Otherwise, leave any single
517  // element constant of the right size alone even if it has the wrong type.
518  auto *STy = dyn_cast<llvm::StructType>(DesiredTy);
519  if (STy && STy->getNumElements() == 1 &&
520  STy->getElementType(0) == Elems[First]->getType())
521  Elems[First] = llvm::ConstantStruct::get(STy, Elems[First]);
522  return;
523  }
524 
525  llvm::Constant *Replacement = buildFrom(
526  CGM, makeArrayRef(Elems).slice(First, Length),
527  makeArrayRef(Offsets).slice(First, Length), Offset, getSize(DesiredTy),
528  /*known to have natural layout=*/false, DesiredTy, false);
529  replace(Elems, First, Last, {Replacement});
530  replace(Offsets, First, Last, {Offset});
531 }
532 
533 //===----------------------------------------------------------------------===//
534 // ConstStructBuilder
535 //===----------------------------------------------------------------------===//
536 
537 class ConstStructBuilder {
538  CodeGenModule &CGM;
540  ConstantAggregateBuilder &Builder;
541  CharUnits StartOffset;
542 
543 public:
544  static llvm::Constant *BuildStruct(ConstantEmitter &Emitter,
545  InitListExpr *ILE, QualType StructTy);
546  static llvm::Constant *BuildStruct(ConstantEmitter &Emitter,
547  const APValue &Value, QualType ValTy);
548  static bool UpdateStruct(ConstantEmitter &Emitter,
549  ConstantAggregateBuilder &Const, CharUnits Offset,
550  InitListExpr *Updater);
551 
552 private:
553  ConstStructBuilder(ConstantEmitter &Emitter,
554  ConstantAggregateBuilder &Builder, CharUnits StartOffset)
555  : CGM(Emitter.CGM), Emitter(Emitter), Builder(Builder),
556  StartOffset(StartOffset) {}
557 
558  bool AppendField(const FieldDecl *Field, uint64_t FieldOffset,
559  llvm::Constant *InitExpr, bool AllowOverwrite = false);
560 
561  bool AppendBytes(CharUnits FieldOffsetInChars, llvm::Constant *InitCst,
562  bool AllowOverwrite = false);
563 
564  bool AppendBitField(const FieldDecl *Field, uint64_t FieldOffset,
565  llvm::ConstantInt *InitExpr, bool AllowOverwrite = false);
566 
567  bool Build(InitListExpr *ILE, bool AllowOverwrite);
568  bool Build(const APValue &Val, const RecordDecl *RD, bool IsPrimaryBase,
569  const CXXRecordDecl *VTableClass, CharUnits BaseOffset);
570  llvm::Constant *Finalize(QualType Ty);
571 };
572 
573 bool ConstStructBuilder::AppendField(
574  const FieldDecl *Field, uint64_t FieldOffset, llvm::Constant *InitCst,
575  bool AllowOverwrite) {
576  const ASTContext &Context = CGM.getContext();
577 
578  CharUnits FieldOffsetInChars = Context.toCharUnitsFromBits(FieldOffset);
579 
580  return AppendBytes(FieldOffsetInChars, InitCst, AllowOverwrite);
581 }
582 
583 bool ConstStructBuilder::AppendBytes(CharUnits FieldOffsetInChars,
584  llvm::Constant *InitCst,
585  bool AllowOverwrite) {
586  return Builder.add(InitCst, StartOffset + FieldOffsetInChars, AllowOverwrite);
587 }
588 
589 bool ConstStructBuilder::AppendBitField(
590  const FieldDecl *Field, uint64_t FieldOffset, llvm::ConstantInt *CI,
591  bool AllowOverwrite) {
592  uint64_t FieldSize = Field->getBitWidthValue(CGM.getContext());
593  llvm::APInt FieldValue = CI->getValue();
594 
595  // Promote the size of FieldValue if necessary
596  // FIXME: This should never occur, but currently it can because initializer
597  // constants are cast to bool, and because clang is not enforcing bitfield
598  // width limits.
599  if (FieldSize > FieldValue.getBitWidth())
600  FieldValue = FieldValue.zext(FieldSize);
601 
602  // Truncate the size of FieldValue to the bit field size.
603  if (FieldSize < FieldValue.getBitWidth())
604  FieldValue = FieldValue.trunc(FieldSize);
605 
606  return Builder.addBits(FieldValue,
607  CGM.getContext().toBits(StartOffset) + FieldOffset,
608  AllowOverwrite);
609 }
610 
611 static bool EmitDesignatedInitUpdater(ConstantEmitter &Emitter,
612  ConstantAggregateBuilder &Const,
613  CharUnits Offset, QualType Type,
614  InitListExpr *Updater) {
615  if (Type->isRecordType())
616  return ConstStructBuilder::UpdateStruct(Emitter, Const, Offset, Updater);
617 
618  auto CAT = Emitter.CGM.getContext().getAsConstantArrayType(Type);
619  if (!CAT)
620  return false;
621  QualType ElemType = CAT->getElementType();
622  CharUnits ElemSize = Emitter.CGM.getContext().getTypeSizeInChars(ElemType);
623  llvm::Type *ElemTy = Emitter.CGM.getTypes().ConvertTypeForMem(ElemType);
624 
625  llvm::Constant *FillC = nullptr;
626  if (Expr *Filler = Updater->getArrayFiller()) {
627  if (!isa<NoInitExpr>(Filler)) {
628  FillC = Emitter.tryEmitAbstractForMemory(Filler, ElemType);
629  if (!FillC)
630  return false;
631  }
632  }
633 
634  unsigned NumElementsToUpdate =
635  FillC ? CAT->getSize().getZExtValue() : Updater->getNumInits();
636  for (unsigned I = 0; I != NumElementsToUpdate; ++I, Offset += ElemSize) {
637  Expr *Init = nullptr;
638  if (I < Updater->getNumInits())
639  Init = Updater->getInit(I);
640 
641  if (!Init && FillC) {
642  if (!Const.add(FillC, Offset, true))
643  return false;
644  } else if (!Init || isa<NoInitExpr>(Init)) {
645  continue;
646  } else if (InitListExpr *ChildILE = dyn_cast<InitListExpr>(Init)) {
647  if (!EmitDesignatedInitUpdater(Emitter, Const, Offset, ElemType,
648  ChildILE))
649  return false;
650  // Attempt to reduce the array element to a single constant if necessary.
651  Const.condense(Offset, ElemTy);
652  } else {
653  llvm::Constant *Val = Emitter.tryEmitPrivateForMemory(Init, ElemType);
654  if (!Const.add(Val, Offset, true))
655  return false;
656  }
657  }
658 
659  return true;
660 }
661 
662 bool ConstStructBuilder::Build(InitListExpr *ILE, bool AllowOverwrite) {
663  RecordDecl *RD = ILE->getType()->castAs<RecordType>()->getDecl();
664  const ASTRecordLayout &Layout = CGM.getContext().getASTRecordLayout(RD);
665 
666  unsigned FieldNo = -1;
667  unsigned ElementNo = 0;
668 
669  // Bail out if we have base classes. We could support these, but they only
670  // arise in C++1z where we will have already constant folded most interesting
671  // cases. FIXME: There are still a few more cases we can handle this way.
672  if (auto *CXXRD = dyn_cast<CXXRecordDecl>(RD))
673  if (CXXRD->getNumBases())
674  return false;
675 
676  for (FieldDecl *Field : RD->fields()) {
677  ++FieldNo;
678 
679  // If this is a union, skip all the fields that aren't being initialized.
680  if (RD->isUnion() &&
682  continue;
683 
684  // Don't emit anonymous bitfields or zero-sized fields.
685  if (Field->isUnnamedBitfield() || Field->isZeroSize(CGM.getContext()))
686  continue;
687 
688  // Get the initializer. A struct can include fields without initializers,
689  // we just use explicit null values for them.
690  Expr *Init = nullptr;
691  if (ElementNo < ILE->getNumInits())
692  Init = ILE->getInit(ElementNo++);
693  if (Init && isa<NoInitExpr>(Init))
694  continue;
695 
696  // When emitting a DesignatedInitUpdateExpr, a nested InitListExpr
697  // represents additional overwriting of our current constant value, and not
698  // a new constant to emit independently.
699  if (AllowOverwrite &&
700  (Field->getType()->isArrayType() || Field->getType()->isRecordType())) {
701  if (auto *SubILE = dyn_cast<InitListExpr>(Init)) {
703  Layout.getFieldOffset(FieldNo));
704  if (!EmitDesignatedInitUpdater(Emitter, Builder, StartOffset + Offset,
705  Field->getType(), SubILE))
706  return false;
707  // If we split apart the field's value, try to collapse it down to a
708  // single value now.
709  Builder.condense(StartOffset + Offset,
710  CGM.getTypes().ConvertTypeForMem(Field->getType()));
711  continue;
712  }
713  }
714 
715  llvm::Constant *EltInit =
716  Init ? Emitter.tryEmitPrivateForMemory(Init, Field->getType())
717  : Emitter.emitNullForMemory(Field->getType());
718  if (!EltInit)
719  return false;
720 
721  if (!Field->isBitField()) {
722  // Handle non-bitfield members.
723  if (!AppendField(Field, Layout.getFieldOffset(FieldNo), EltInit,
724  AllowOverwrite))
725  return false;
726  // After emitting a non-empty field with [[no_unique_address]], we may
727  // need to overwrite its tail padding.
728  if (Field->hasAttr<NoUniqueAddressAttr>())
729  AllowOverwrite = true;
730  } else {
731  // Otherwise we have a bitfield.
732  if (auto *CI = dyn_cast<llvm::ConstantInt>(EltInit)) {
733  if (!AppendBitField(Field, Layout.getFieldOffset(FieldNo), CI,
734  AllowOverwrite))
735  return false;
736  } else {
737  // We are trying to initialize a bitfield with a non-trivial constant,
738  // this must require run-time code.
739  return false;
740  }
741  }
742  }
743 
744  return true;
745 }
746 
747 namespace {
748 struct BaseInfo {
749  BaseInfo(const CXXRecordDecl *Decl, CharUnits Offset, unsigned Index)
750  : Decl(Decl), Offset(Offset), Index(Index) {
751  }
752 
753  const CXXRecordDecl *Decl;
755  unsigned Index;
756 
757  bool operator<(const BaseInfo &O) const { return Offset < O.Offset; }
758 };
759 }
760 
761 bool ConstStructBuilder::Build(const APValue &Val, const RecordDecl *RD,
762  bool IsPrimaryBase,
763  const CXXRecordDecl *VTableClass,
764  CharUnits Offset) {
765  const ASTRecordLayout &Layout = CGM.getContext().getASTRecordLayout(RD);
766 
767  if (const CXXRecordDecl *CD = dyn_cast<CXXRecordDecl>(RD)) {
768  // Add a vtable pointer, if we need one and it hasn't already been added.
769  if (CD->isDynamicClass() && !IsPrimaryBase) {
770  llvm::Constant *VTableAddressPoint =
772  BaseSubobject(CD, Offset), VTableClass);
773  if (!AppendBytes(Offset, VTableAddressPoint))
774  return false;
775  }
776 
777  // Accumulate and sort bases, in order to visit them in address order, which
778  // may not be the same as declaration order.
780  Bases.reserve(CD->getNumBases());
781  unsigned BaseNo = 0;
782  for (CXXRecordDecl::base_class_const_iterator Base = CD->bases_begin(),
783  BaseEnd = CD->bases_end(); Base != BaseEnd; ++Base, ++BaseNo) {
784  assert(!Base->isVirtual() && "should not have virtual bases here");
785  const CXXRecordDecl *BD = Base->getType()->getAsCXXRecordDecl();
786  CharUnits BaseOffset = Layout.getBaseClassOffset(BD);
787  Bases.push_back(BaseInfo(BD, BaseOffset, BaseNo));
788  }
789  llvm::stable_sort(Bases);
790 
791  for (unsigned I = 0, N = Bases.size(); I != N; ++I) {
792  BaseInfo &Base = Bases[I];
793 
794  bool IsPrimaryBase = Layout.getPrimaryBase() == Base.Decl;
795  Build(Val.getStructBase(Base.Index), Base.Decl, IsPrimaryBase,
796  VTableClass, Offset + Base.Offset);
797  }
798  }
799 
800  unsigned FieldNo = 0;
801  uint64_t OffsetBits = CGM.getContext().toBits(Offset);
802 
803  bool AllowOverwrite = false;
804  for (RecordDecl::field_iterator Field = RD->field_begin(),
805  FieldEnd = RD->field_end(); Field != FieldEnd; ++Field, ++FieldNo) {
806  // If this is a union, skip all the fields that aren't being initialized.
807  if (RD->isUnion() && !declaresSameEntity(Val.getUnionField(), *Field))
808  continue;
809 
810  // Don't emit anonymous bitfields or zero-sized fields.
811  if (Field->isUnnamedBitfield() || Field->isZeroSize(CGM.getContext()))
812  continue;
813 
814  // Emit the value of the initializer.
815  const APValue &FieldValue =
816  RD->isUnion() ? Val.getUnionValue() : Val.getStructField(FieldNo);
817  llvm::Constant *EltInit =
818  Emitter.tryEmitPrivateForMemory(FieldValue, Field->getType());
819  if (!EltInit)
820  return false;
821 
822  if (!Field->isBitField()) {
823  // Handle non-bitfield members.
824  if (!AppendField(*Field, Layout.getFieldOffset(FieldNo) + OffsetBits,
825  EltInit, AllowOverwrite))
826  return false;
827  // After emitting a non-empty field with [[no_unique_address]], we may
828  // need to overwrite its tail padding.
829  if (Field->hasAttr<NoUniqueAddressAttr>())
830  AllowOverwrite = true;
831  } else {
832  // Otherwise we have a bitfield.
833  if (!AppendBitField(*Field, Layout.getFieldOffset(FieldNo) + OffsetBits,
834  cast<llvm::ConstantInt>(EltInit), AllowOverwrite))
835  return false;
836  }
837  }
838 
839  return true;
840 }
841 
842 llvm::Constant *ConstStructBuilder::Finalize(QualType Type) {
843  RecordDecl *RD = Type->castAs<RecordType>()->getDecl();
844  llvm::Type *ValTy = CGM.getTypes().ConvertType(Type);
845  return Builder.build(ValTy, RD->hasFlexibleArrayMember());
846 }
847 
848 llvm::Constant *ConstStructBuilder::BuildStruct(ConstantEmitter &Emitter,
849  InitListExpr *ILE,
850  QualType ValTy) {
851  ConstantAggregateBuilder Const(Emitter.CGM);
852  ConstStructBuilder Builder(Emitter, Const, CharUnits::Zero());
853 
854  if (!Builder.Build(ILE, /*AllowOverwrite*/false))
855  return nullptr;
856 
857  return Builder.Finalize(ValTy);
858 }
859 
860 llvm::Constant *ConstStructBuilder::BuildStruct(ConstantEmitter &Emitter,
861  const APValue &Val,
862  QualType ValTy) {
863  ConstantAggregateBuilder Const(Emitter.CGM);
864  ConstStructBuilder Builder(Emitter, Const, CharUnits::Zero());
865 
866  const RecordDecl *RD = ValTy->castAs<RecordType>()->getDecl();
867  const CXXRecordDecl *CD = dyn_cast<CXXRecordDecl>(RD);
868  if (!Builder.Build(Val, RD, false, CD, CharUnits::Zero()))
869  return nullptr;
870 
871  return Builder.Finalize(ValTy);
872 }
873 
874 bool ConstStructBuilder::UpdateStruct(ConstantEmitter &Emitter,
875  ConstantAggregateBuilder &Const,
876  CharUnits Offset, InitListExpr *Updater) {
877  return ConstStructBuilder(Emitter, Const, Offset)
878  .Build(Updater, /*AllowOverwrite*/ true);
879 }
880 
881 //===----------------------------------------------------------------------===//
882 // ConstExprEmitter
883 //===----------------------------------------------------------------------===//
884 
885 static ConstantAddress tryEmitGlobalCompoundLiteral(CodeGenModule &CGM,
886  CodeGenFunction *CGF,
887  const CompoundLiteralExpr *E) {
888  CharUnits Align = CGM.getContext().getTypeAlignInChars(E->getType());
889  if (llvm::GlobalVariable *Addr =
891  return ConstantAddress(Addr, Align);
892 
893  LangAS addressSpace = E->getType().getAddressSpace();
894 
895  ConstantEmitter emitter(CGM, CGF);
896  llvm::Constant *C = emitter.tryEmitForInitializer(E->getInitializer(),
897  addressSpace, E->getType());
898  if (!C) {
899  assert(!E->isFileScope() &&
900  "file-scope compound literal did not have constant initializer!");
901  return ConstantAddress::invalid();
902  }
903 
904  auto GV = new llvm::GlobalVariable(CGM.getModule(), C->getType(),
905  CGM.isTypeConstant(E->getType(), true),
907  C, ".compoundliteral", nullptr,
908  llvm::GlobalVariable::NotThreadLocal,
909  CGM.getContext().getTargetAddressSpace(addressSpace));
910  emitter.finalize(GV);
911  GV->setAlignment(Align.getAsAlign());
913  return ConstantAddress(GV, Align);
914 }
915 
916 static llvm::Constant *
917 EmitArrayConstant(CodeGenModule &CGM, llvm::ArrayType *DesiredType,
918  llvm::Type *CommonElementType, unsigned ArrayBound,
920  llvm::Constant *Filler) {
921  // Figure out how long the initial prefix of non-zero elements is.
922  unsigned NonzeroLength = ArrayBound;
923  if (Elements.size() < NonzeroLength && Filler->isNullValue())
924  NonzeroLength = Elements.size();
925  if (NonzeroLength == Elements.size()) {
926  while (NonzeroLength > 0 && Elements[NonzeroLength - 1]->isNullValue())
927  --NonzeroLength;
928  }
929 
930  if (NonzeroLength == 0)
931  return llvm::ConstantAggregateZero::get(DesiredType);
932 
933  // Add a zeroinitializer array filler if we have lots of trailing zeroes.
934  unsigned TrailingZeroes = ArrayBound - NonzeroLength;
935  if (TrailingZeroes >= 8) {
936  assert(Elements.size() >= NonzeroLength &&
937  "missing initializer for non-zero element");
938 
939  // If all the elements had the same type up to the trailing zeroes, emit a
940  // struct of two arrays (the nonzero data and the zeroinitializer).
941  if (CommonElementType && NonzeroLength >= 8) {
942  llvm::Constant *Initial = llvm::ConstantArray::get(
943  llvm::ArrayType::get(CommonElementType, NonzeroLength),
944  makeArrayRef(Elements).take_front(NonzeroLength));
945  Elements.resize(2);
946  Elements[0] = Initial;
947  } else {
948  Elements.resize(NonzeroLength + 1);
949  }
950 
951  auto *FillerType =
952  CommonElementType ? CommonElementType : DesiredType->getElementType();
953  FillerType = llvm::ArrayType::get(FillerType, TrailingZeroes);
954  Elements.back() = llvm::ConstantAggregateZero::get(FillerType);
955  CommonElementType = nullptr;
956  } else if (Elements.size() != ArrayBound) {
957  // Otherwise pad to the right size with the filler if necessary.
958  Elements.resize(ArrayBound, Filler);
959  if (Filler->getType() != CommonElementType)
960  CommonElementType = nullptr;
961  }
962 
963  // If all elements have the same type, just emit an array constant.
964  if (CommonElementType)
965  return llvm::ConstantArray::get(
966  llvm::ArrayType::get(CommonElementType, ArrayBound), Elements);
967 
968  // We have mixed types. Use a packed struct.
970  Types.reserve(Elements.size());
971  for (llvm::Constant *Elt : Elements)
972  Types.push_back(Elt->getType());
973  llvm::StructType *SType =
974  llvm::StructType::get(CGM.getLLVMContext(), Types, true);
975  return llvm::ConstantStruct::get(SType, Elements);
976 }
977 
978 // This class only needs to handle arrays, structs and unions. Outside C++11
979 // mode, we don't currently constant fold those types. All other types are
980 // handled by constant folding.
981 //
982 // Constant folding is currently missing support for a few features supported
983 // here: CK_ToUnion, CK_ReinterpretMemberPointer, and DesignatedInitUpdateExpr.
984 class ConstExprEmitter :
985  public StmtVisitor<ConstExprEmitter, llvm::Constant*, QualType> {
986  CodeGenModule &CGM;
987  ConstantEmitter &Emitter;
988  llvm::LLVMContext &VMContext;
989 public:
990  ConstExprEmitter(ConstantEmitter &emitter)
991  : CGM(emitter.CGM), Emitter(emitter), VMContext(CGM.getLLVMContext()) {
992  }
993 
994  //===--------------------------------------------------------------------===//
995  // Visitor Methods
996  //===--------------------------------------------------------------------===//
997 
998  llvm::Constant *VisitStmt(Stmt *S, QualType T) {
999  return nullptr;
1000  }
1001 
1002  llvm::Constant *VisitConstantExpr(ConstantExpr *CE, QualType T) {
1003  return Visit(CE->getSubExpr(), T);
1004  }
1005 
1006  llvm::Constant *VisitParenExpr(ParenExpr *PE, QualType T) {
1007  return Visit(PE->getSubExpr(), T);
1008  }
1009 
1010  llvm::Constant *
1011  VisitSubstNonTypeTemplateParmExpr(SubstNonTypeTemplateParmExpr *PE,
1012  QualType T) {
1013  return Visit(PE->getReplacement(), T);
1014  }
1015 
1016  llvm::Constant *VisitGenericSelectionExpr(GenericSelectionExpr *GE,
1017  QualType T) {
1018  return Visit(GE->getResultExpr(), T);
1019  }
1020 
1021  llvm::Constant *VisitChooseExpr(ChooseExpr *CE, QualType T) {
1022  return Visit(CE->getChosenSubExpr(), T);
1023  }
1024 
1025  llvm::Constant *VisitCompoundLiteralExpr(CompoundLiteralExpr *E, QualType T) {
1026  return Visit(E->getInitializer(), T);
1027  }
1028 
1029  llvm::Constant *VisitCastExpr(CastExpr *E, QualType destType) {
1030  if (const auto *ECE = dyn_cast<ExplicitCastExpr>(E))
1031  CGM.EmitExplicitCastExprType(ECE, Emitter.CGF);
1032  Expr *subExpr = E->getSubExpr();
1033 
1034  switch (E->getCastKind()) {
1035  case CK_ToUnion: {
1036  // GCC cast to union extension
1037  assert(E->getType()->isUnionType() &&
1038  "Destination type is not union type!");
1039 
1040  auto field = E->getTargetUnionField();
1041 
1042  auto C = Emitter.tryEmitPrivateForMemory(subExpr, field->getType());
1043  if (!C) return nullptr;
1044 
1045  auto destTy = ConvertType(destType);
1046  if (C->getType() == destTy) return C;
1047 
1048  // Build a struct with the union sub-element as the first member,
1049  // and padded to the appropriate size.
1052  Elts.push_back(C);
1053  Types.push_back(C->getType());
1054  unsigned CurSize = CGM.getDataLayout().getTypeAllocSize(C->getType());
1055  unsigned TotalSize = CGM.getDataLayout().getTypeAllocSize(destTy);
1056 
1057  assert(CurSize <= TotalSize && "Union size mismatch!");
1058  if (unsigned NumPadBytes = TotalSize - CurSize) {
1059  llvm::Type *Ty = CGM.Int8Ty;
1060  if (NumPadBytes > 1)
1061  Ty = llvm::ArrayType::get(Ty, NumPadBytes);
1062 
1063  Elts.push_back(llvm::UndefValue::get(Ty));
1064  Types.push_back(Ty);
1065  }
1066 
1067  llvm::StructType *STy = llvm::StructType::get(VMContext, Types, false);
1068  return llvm::ConstantStruct::get(STy, Elts);
1069  }
1070 
1071  case CK_AddressSpaceConversion: {
1072  auto C = Emitter.tryEmitPrivate(subExpr, subExpr->getType());
1073  if (!C) return nullptr;
1074  LangAS destAS = E->getType()->getPointeeType().getAddressSpace();
1075  LangAS srcAS = subExpr->getType()->getPointeeType().getAddressSpace();
1076  llvm::Type *destTy = ConvertType(E->getType());
1077  return CGM.getTargetCodeGenInfo().performAddrSpaceCast(CGM, C, srcAS,
1078  destAS, destTy);
1079  }
1080 
1081  case CK_LValueToRValue:
1082  case CK_AtomicToNonAtomic:
1083  case CK_NonAtomicToAtomic:
1084  case CK_NoOp:
1085  case CK_ConstructorConversion:
1086  return Visit(subExpr, destType);
1087 
1088  case CK_IntToOCLSampler:
1089  llvm_unreachable("global sampler variables are not generated");
1090 
1091  case CK_Dependent: llvm_unreachable("saw dependent cast!");
1092 
1093  case CK_BuiltinFnToFnPtr:
1094  llvm_unreachable("builtin functions are handled elsewhere");
1095 
1096  case CK_ReinterpretMemberPointer:
1097  case CK_DerivedToBaseMemberPointer:
1098  case CK_BaseToDerivedMemberPointer: {
1099  auto C = Emitter.tryEmitPrivate(subExpr, subExpr->getType());
1100  if (!C) return nullptr;
1101  return CGM.getCXXABI().EmitMemberPointerConversion(E, C);
1102  }
1103 
1104  // These will never be supported.
1105  case CK_ObjCObjectLValueCast:
1106  case CK_ARCProduceObject:
1107  case CK_ARCConsumeObject:
1108  case CK_ARCReclaimReturnedObject:
1109  case CK_ARCExtendBlockObject:
1110  case CK_CopyAndAutoreleaseBlockObject:
1111  return nullptr;
1112 
1113  // These don't need to be handled here because Evaluate knows how to
1114  // evaluate them in the cases where they can be folded.
1115  case CK_BitCast:
1116  case CK_ToVoid:
1117  case CK_Dynamic:
1118  case CK_LValueBitCast:
1119  case CK_LValueToRValueBitCast:
1120  case CK_NullToMemberPointer:
1121  case CK_UserDefinedConversion:
1122  case CK_CPointerToObjCPointerCast:
1123  case CK_BlockPointerToObjCPointerCast:
1124  case CK_AnyPointerToBlockPointerCast:
1125  case CK_ArrayToPointerDecay:
1126  case CK_FunctionToPointerDecay:
1127  case CK_BaseToDerived:
1128  case CK_DerivedToBase:
1129  case CK_UncheckedDerivedToBase:
1130  case CK_MemberPointerToBoolean:
1131  case CK_VectorSplat:
1132  case CK_FloatingRealToComplex:
1133  case CK_FloatingComplexToReal:
1134  case CK_FloatingComplexToBoolean:
1135  case CK_FloatingComplexCast:
1136  case CK_FloatingComplexToIntegralComplex:
1137  case CK_IntegralRealToComplex:
1138  case CK_IntegralComplexToReal:
1139  case CK_IntegralComplexToBoolean:
1140  case CK_IntegralComplexCast:
1141  case CK_IntegralComplexToFloatingComplex:
1142  case CK_PointerToIntegral:
1143  case CK_PointerToBoolean:
1144  case CK_NullToPointer:
1145  case CK_IntegralCast:
1146  case CK_BooleanToSignedIntegral:
1147  case CK_IntegralToPointer:
1148  case CK_IntegralToBoolean:
1149  case CK_IntegralToFloating:
1150  case CK_FloatingToIntegral:
1151  case CK_FloatingToBoolean:
1152  case CK_FloatingCast:
1153  case CK_FixedPointCast:
1154  case CK_FixedPointToBoolean:
1155  case CK_FixedPointToIntegral:
1156  case CK_IntegralToFixedPoint:
1157  case CK_ZeroToOCLOpaqueType:
1158  return nullptr;
1159  }
1160  llvm_unreachable("Invalid CastKind");
1161  }
1162 
1163  llvm::Constant *VisitCXXDefaultInitExpr(CXXDefaultInitExpr *DIE, QualType T) {
1164  // No need for a DefaultInitExprScope: we don't handle 'this' in a
1165  // constant expression.
1166  return Visit(DIE->getExpr(), T);
1167  }
1168 
1169  llvm::Constant *VisitExprWithCleanups(ExprWithCleanups *E, QualType T) {
1170  if (!E->cleanupsHaveSideEffects())
1171  return Visit(E->getSubExpr(), T);
1172  return nullptr;
1173  }
1174 
1175  llvm::Constant *VisitMaterializeTemporaryExpr(MaterializeTemporaryExpr *E,
1176  QualType T) {
1177  return Visit(E->getSubExpr(), T);
1178  }
1179 
1180  llvm::Constant *EmitArrayInitialization(InitListExpr *ILE, QualType T) {
1181  auto *CAT = CGM.getContext().getAsConstantArrayType(ILE->getType());
1182  assert(CAT && "can't emit array init for non-constant-bound array");
1183  unsigned NumInitElements = ILE->getNumInits();
1184  unsigned NumElements = CAT->getSize().getZExtValue();
1185 
1186  // Initialising an array requires us to automatically
1187  // initialise any elements that have not been initialised explicitly
1188  unsigned NumInitableElts = std::min(NumInitElements, NumElements);
1189 
1190  QualType EltType = CAT->getElementType();
1191 
1192  // Initialize remaining array elements.
1193  llvm::Constant *fillC = nullptr;
1194  if (Expr *filler = ILE->getArrayFiller()) {
1195  fillC = Emitter.tryEmitAbstractForMemory(filler, EltType);
1196  if (!fillC)
1197  return nullptr;
1198  }
1199 
1200  // Copy initializer elements.
1202  if (fillC && fillC->isNullValue())
1203  Elts.reserve(NumInitableElts + 1);
1204  else
1205  Elts.reserve(NumElements);
1206 
1207  llvm::Type *CommonElementType = nullptr;
1208  for (unsigned i = 0; i < NumInitableElts; ++i) {
1209  Expr *Init = ILE->getInit(i);
1210  llvm::Constant *C = Emitter.tryEmitPrivateForMemory(Init, EltType);
1211  if (!C)
1212  return nullptr;
1213  if (i == 0)
1214  CommonElementType = C->getType();
1215  else if (C->getType() != CommonElementType)
1216  CommonElementType = nullptr;
1217  Elts.push_back(C);
1218  }
1219 
1220  llvm::ArrayType *Desired =
1221  cast<llvm::ArrayType>(CGM.getTypes().ConvertType(ILE->getType()));
1222  return EmitArrayConstant(CGM, Desired, CommonElementType, NumElements, Elts,
1223  fillC);
1224  }
1225 
1226  llvm::Constant *EmitRecordInitialization(InitListExpr *ILE, QualType T) {
1227  return ConstStructBuilder::BuildStruct(Emitter, ILE, T);
1228  }
1229 
1230  llvm::Constant *VisitImplicitValueInitExpr(ImplicitValueInitExpr* E,
1231  QualType T) {
1232  return CGM.EmitNullConstant(T);
1233  }
1234 
1235  llvm::Constant *VisitInitListExpr(InitListExpr *ILE, QualType T) {
1236  if (ILE->isTransparent())
1237  return Visit(ILE->getInit(0), T);
1238 
1239  if (ILE->getType()->isArrayType())
1240  return EmitArrayInitialization(ILE, T);
1241 
1242  if (ILE->getType()->isRecordType())
1243  return EmitRecordInitialization(ILE, T);
1244 
1245  return nullptr;
1246  }
1247 
1248  llvm::Constant *VisitDesignatedInitUpdateExpr(DesignatedInitUpdateExpr *E,
1249  QualType destType) {
1250  auto C = Visit(E->getBase(), destType);
1251  if (!C)
1252  return nullptr;
1253 
1254  ConstantAggregateBuilder Const(CGM);
1255  Const.add(C, CharUnits::Zero(), false);
1256 
1257  if (!EmitDesignatedInitUpdater(Emitter, Const, CharUnits::Zero(), destType,
1258  E->getUpdater()))
1259  return nullptr;
1260 
1261  llvm::Type *ValTy = CGM.getTypes().ConvertType(destType);
1262  bool HasFlexibleArray = false;
1263  if (auto *RT = destType->getAs<RecordType>())
1264  HasFlexibleArray = RT->getDecl()->hasFlexibleArrayMember();
1265  return Const.build(ValTy, HasFlexibleArray);
1266  }
1267 
1268  llvm::Constant *VisitCXXConstructExpr(CXXConstructExpr *E, QualType Ty) {
1269  if (!E->getConstructor()->isTrivial())
1270  return nullptr;
1271 
1272  // FIXME: We should not have to call getBaseElementType here.
1273  const auto *RT =
1275  const CXXRecordDecl *RD = cast<CXXRecordDecl>(RT->getDecl());
1276 
1277  // If the class doesn't have a trivial destructor, we can't emit it as a
1278  // constant expr.
1279  if (!RD->hasTrivialDestructor())
1280  return nullptr;
1281 
1282  // Only copy and default constructors can be trivial.
1283 
1284 
1285  if (E->getNumArgs()) {
1286  assert(E->getNumArgs() == 1 && "trivial ctor with > 1 argument");
1287  assert(E->getConstructor()->isCopyOrMoveConstructor() &&
1288  "trivial ctor has argument but isn't a copy/move ctor");
1289 
1290  Expr *Arg = E->getArg(0);
1291  assert(CGM.getContext().hasSameUnqualifiedType(Ty, Arg->getType()) &&
1292  "argument to copy ctor is of wrong type");
1293 
1294  return Visit(Arg, Ty);
1295  }
1296 
1297  return CGM.EmitNullConstant(Ty);
1298  }
1299 
1300  llvm::Constant *VisitStringLiteral(StringLiteral *E, QualType T) {
1301  // This is a string literal initializing an array in an initializer.
1302  return CGM.GetConstantArrayFromStringLiteral(E);
1303  }
1304 
1305  llvm::Constant *VisitObjCEncodeExpr(ObjCEncodeExpr *E, QualType T) {
1306  // This must be an @encode initializing an array in a static initializer.
1307  // Don't emit it as the address of the string, emit the string data itself
1308  // as an inline array.
1309  std::string Str;
1311  const ConstantArrayType *CAT = CGM.getContext().getAsConstantArrayType(T);
1312 
1313  // Resize the string to the right size, adding zeros at the end, or
1314  // truncating as needed.
1315  Str.resize(CAT->getSize().getZExtValue(), '\0');
1316  return llvm::ConstantDataArray::getString(VMContext, Str, false);
1317  }
1318 
1319  llvm::Constant *VisitUnaryExtension(const UnaryOperator *E, QualType T) {
1320  return Visit(E->getSubExpr(), T);
1321  }
1322 
1323  // Utility methods
1324  llvm::Type *ConvertType(QualType T) {
1325  return CGM.getTypes().ConvertType(T);
1326  }
1327 };
1328 
1329 } // end anonymous namespace.
1330 
1331 llvm::Constant *ConstantEmitter::validateAndPopAbstract(llvm::Constant *C,
1332  AbstractState saved) {
1333  Abstract = saved.OldValue;
1334 
1335  assert(saved.OldPlaceholdersSize == PlaceholderAddresses.size() &&
1336  "created a placeholder while doing an abstract emission?");
1337 
1338  // No validation necessary for now.
1339  // No cleanup to do for now.
1340  return C;
1341 }
1342 
1343 llvm::Constant *
1345  auto state = pushAbstract();
1346  auto C = tryEmitPrivateForVarInit(D);
1347  return validateAndPopAbstract(C, state);
1348 }
1349 
1350 llvm::Constant *
1352  auto state = pushAbstract();
1353  auto C = tryEmitPrivate(E, destType);
1354  return validateAndPopAbstract(C, state);
1355 }
1356 
1357 llvm::Constant *
1359  auto state = pushAbstract();
1360  auto C = tryEmitPrivate(value, destType);
1361  return validateAndPopAbstract(C, state);
1362 }
1363 
1364 llvm::Constant *
1366  auto state = pushAbstract();
1367  auto C = tryEmitPrivate(E, destType);
1368  C = validateAndPopAbstract(C, state);
1369  if (!C) {
1370  CGM.Error(E->getExprLoc(),
1371  "internal error: could not emit constant value \"abstractly\"");
1372  C = CGM.EmitNullConstant(destType);
1373  }
1374  return C;
1375 }
1376 
1377 llvm::Constant *
1379  QualType destType) {
1380  auto state = pushAbstract();
1381  auto C = tryEmitPrivate(value, destType);
1382  C = validateAndPopAbstract(C, state);
1383  if (!C) {
1384  CGM.Error(loc,
1385  "internal error: could not emit constant value \"abstractly\"");
1386  C = CGM.EmitNullConstant(destType);
1387  }
1388  return C;
1389 }
1390 
1392  initializeNonAbstract(D.getType().getAddressSpace());
1393  return markIfFailed(tryEmitPrivateForVarInit(D));
1394 }
1395 
1397  LangAS destAddrSpace,
1398  QualType destType) {
1399  initializeNonAbstract(destAddrSpace);
1400  return markIfFailed(tryEmitPrivateForMemory(E, destType));
1401 }
1402 
1403 llvm::Constant *ConstantEmitter::emitForInitializer(const APValue &value,
1404  LangAS destAddrSpace,
1405  QualType destType) {
1406  initializeNonAbstract(destAddrSpace);
1407  auto C = tryEmitPrivateForMemory(value, destType);
1408  assert(C && "couldn't emit constant value non-abstractly?");
1409  return C;
1410 }
1411 
1413  assert(!Abstract && "cannot get current address for abstract constant");
1414 
1415 
1416 
1417  // Make an obviously ill-formed global that should blow up compilation
1418  // if it survives.
1419  auto global = new llvm::GlobalVariable(CGM.getModule(), CGM.Int8Ty, true,
1420  llvm::GlobalValue::PrivateLinkage,
1421  /*init*/ nullptr,
1422  /*name*/ "",
1423  /*before*/ nullptr,
1424  llvm::GlobalVariable::NotThreadLocal,
1425  CGM.getContext().getTargetAddressSpace(DestAddressSpace));
1426 
1427  PlaceholderAddresses.push_back(std::make_pair(nullptr, global));
1428 
1429  return global;
1430 }
1431 
1433  llvm::GlobalValue *placeholder) {
1434  assert(!PlaceholderAddresses.empty());
1435  assert(PlaceholderAddresses.back().first == nullptr);
1436  assert(PlaceholderAddresses.back().second == placeholder);
1437  PlaceholderAddresses.back().first = signal;
1438 }
1439 
1440 namespace {
1441  struct ReplacePlaceholders {
1442  CodeGenModule &CGM;
1443 
1444  /// The base address of the global.
1445  llvm::Constant *Base;
1446  llvm::Type *BaseValueTy = nullptr;
1447 
1448  /// The placeholder addresses that were registered during emission.
1449  llvm::DenseMap<llvm::Constant*, llvm::GlobalVariable*> PlaceholderAddresses;
1450 
1451  /// The locations of the placeholder signals.
1452  llvm::DenseMap<llvm::GlobalVariable*, llvm::Constant*> Locations;
1453 
1454  /// The current index stack. We use a simple unsigned stack because
1455  /// we assume that placeholders will be relatively sparse in the
1456  /// initializer, but we cache the index values we find just in case.
1459 
1460  ReplacePlaceholders(CodeGenModule &CGM, llvm::Constant *base,
1461  ArrayRef<std::pair<llvm::Constant*,
1462  llvm::GlobalVariable*>> addresses)
1463  : CGM(CGM), Base(base),
1464  PlaceholderAddresses(addresses.begin(), addresses.end()) {
1465  }
1466 
1467  void replaceInInitializer(llvm::Constant *init) {
1468  // Remember the type of the top-most initializer.
1469  BaseValueTy = init->getType();
1470 
1471  // Initialize the stack.
1472  Indices.push_back(0);
1473  IndexValues.push_back(nullptr);
1474 
1475  // Recurse into the initializer.
1476  findLocations(init);
1477 
1478  // Check invariants.
1479  assert(IndexValues.size() == Indices.size() && "mismatch");
1480  assert(Indices.size() == 1 && "didn't pop all indices");
1481 
1482  // Do the replacement; this basically invalidates 'init'.
1483  assert(Locations.size() == PlaceholderAddresses.size() &&
1484  "missed a placeholder?");
1485 
1486  // We're iterating over a hashtable, so this would be a source of
1487  // non-determinism in compiler output *except* that we're just
1488  // messing around with llvm::Constant structures, which never itself
1489  // does anything that should be visible in compiler output.
1490  for (auto &entry : Locations) {
1491  assert(entry.first->getParent() == nullptr && "not a placeholder!");
1492  entry.first->replaceAllUsesWith(entry.second);
1493  entry.first->eraseFromParent();
1494  }
1495  }
1496 
1497  private:
1498  void findLocations(llvm::Constant *init) {
1499  // Recurse into aggregates.
1500  if (auto agg = dyn_cast<llvm::ConstantAggregate>(init)) {
1501  for (unsigned i = 0, e = agg->getNumOperands(); i != e; ++i) {
1502  Indices.push_back(i);
1503  IndexValues.push_back(nullptr);
1504 
1505  findLocations(agg->getOperand(i));
1506 
1507  IndexValues.pop_back();
1508  Indices.pop_back();
1509  }
1510  return;
1511  }
1512 
1513  // Otherwise, check for registered constants.
1514  while (true) {
1515  auto it = PlaceholderAddresses.find(init);
1516  if (it != PlaceholderAddresses.end()) {
1517  setLocation(it->second);
1518  break;
1519  }
1520 
1521  // Look through bitcasts or other expressions.
1522  if (auto expr = dyn_cast<llvm::ConstantExpr>(init)) {
1523  init = expr->getOperand(0);
1524  } else {
1525  break;
1526  }
1527  }
1528  }
1529 
1530  void setLocation(llvm::GlobalVariable *placeholder) {
1531  assert(Locations.find(placeholder) == Locations.end() &&
1532  "already found location for placeholder!");
1533 
1534  // Lazily fill in IndexValues with the values from Indices.
1535  // We do this in reverse because we should always have a strict
1536  // prefix of indices from the start.
1537  assert(Indices.size() == IndexValues.size());
1538  for (size_t i = Indices.size() - 1; i != size_t(-1); --i) {
1539  if (IndexValues[i]) {
1540 #ifndef NDEBUG
1541  for (size_t j = 0; j != i + 1; ++j) {
1542  assert(IndexValues[j] &&
1543  isa<llvm::ConstantInt>(IndexValues[j]) &&
1544  cast<llvm::ConstantInt>(IndexValues[j])->getZExtValue()
1545  == Indices[j]);
1546  }
1547 #endif
1548  break;
1549  }
1550 
1551  IndexValues[i] = llvm::ConstantInt::get(CGM.Int32Ty, Indices[i]);
1552  }
1553 
1554  // Form a GEP and then bitcast to the placeholder type so that the
1555  // replacement will succeed.
1556  llvm::Constant *location =
1557  llvm::ConstantExpr::getInBoundsGetElementPtr(BaseValueTy,
1558  Base, IndexValues);
1559  location = llvm::ConstantExpr::getBitCast(location,
1560  placeholder->getType());
1561 
1562  Locations.insert({placeholder, location});
1563  }
1564  };
1565 }
1566 
1567 void ConstantEmitter::finalize(llvm::GlobalVariable *global) {
1568  assert(InitializedNonAbstract &&
1569  "finalizing emitter that was used for abstract emission?");
1570  assert(!Finalized && "finalizing emitter multiple times");
1571  assert(global->getInitializer());
1572 
1573  // Note that we might also be Failed.
1574  Finalized = true;
1575 
1576  if (!PlaceholderAddresses.empty()) {
1577  ReplacePlaceholders(CGM, global, PlaceholderAddresses)
1578  .replaceInInitializer(global->getInitializer());
1579  PlaceholderAddresses.clear(); // satisfy
1580  }
1581 }
1582 
1584  assert((!InitializedNonAbstract || Finalized || Failed) &&
1585  "not finalized after being initialized for non-abstract emission");
1586  assert(PlaceholderAddresses.empty() && "unhandled placeholders");
1587 }
1588 
1590  if (auto AT = type->getAs<AtomicType>()) {
1591  return CGM.getContext().getQualifiedType(AT->getValueType(),
1592  type.getQualifiers());
1593  }
1594  return type;
1595 }
1596 
1598  // Make a quick check if variable can be default NULL initialized
1599  // and avoid going through rest of code which may do, for c++11,
1600  // initialization of memory to all NULLs.
1601  if (!D.hasLocalStorage()) {
1603  if (Ty->isRecordType())
1604  if (const CXXConstructExpr *E =
1605  dyn_cast_or_null<CXXConstructExpr>(D.getInit())) {
1606  const CXXConstructorDecl *CD = E->getConstructor();
1607  if (CD->isTrivial() && CD->isDefaultConstructor())
1608  return CGM.EmitNullConstant(D.getType());
1609  }
1610  InConstantContext = true;
1611  }
1612 
1613  QualType destType = D.getType();
1614 
1615  // Try to emit the initializer. Note that this can allow some things that
1616  // are not allowed by tryEmitPrivateForMemory alone.
1617  if (auto value = D.evaluateValue()) {
1618  return tryEmitPrivateForMemory(*value, destType);
1619  }
1620 
1621  // FIXME: Implement C++11 [basic.start.init]p2: if the initializer of a
1622  // reference is a constant expression, and the reference binds to a temporary,
1623  // then constant initialization is performed. ConstExprEmitter will
1624  // incorrectly emit a prvalue constant in this case, and the calling code
1625  // interprets that as the (pointer) value of the reference, rather than the
1626  // desired value of the referee.
1627  if (destType->isReferenceType())
1628  return nullptr;
1629 
1630  const Expr *E = D.getInit();
1631  assert(E && "No initializer to emit");
1632 
1633  auto nonMemoryDestType = getNonMemoryType(CGM, destType);
1634  auto C =
1635  ConstExprEmitter(*this).Visit(const_cast<Expr*>(E), nonMemoryDestType);
1636  return (C ? emitForMemory(C, destType) : nullptr);
1637 }
1638 
1639 llvm::Constant *
1641  auto nonMemoryDestType = getNonMemoryType(CGM, destType);
1642  auto C = tryEmitAbstract(E, nonMemoryDestType);
1643  return (C ? emitForMemory(C, destType) : nullptr);
1644 }
1645 
1646 llvm::Constant *
1648  QualType destType) {
1649  auto nonMemoryDestType = getNonMemoryType(CGM, destType);
1650  auto C = tryEmitAbstract(value, nonMemoryDestType);
1651  return (C ? emitForMemory(C, destType) : nullptr);
1652 }
1653 
1655  QualType destType) {
1656  auto nonMemoryDestType = getNonMemoryType(CGM, destType);
1657  llvm::Constant *C = tryEmitPrivate(E, nonMemoryDestType);
1658  return (C ? emitForMemory(C, destType) : nullptr);
1659 }
1660 
1662  QualType destType) {
1663  auto nonMemoryDestType = getNonMemoryType(CGM, destType);
1664  auto C = tryEmitPrivate(value, nonMemoryDestType);
1665  return (C ? emitForMemory(C, destType) : nullptr);
1666 }
1667 
1669  llvm::Constant *C,
1670  QualType destType) {
1671  // For an _Atomic-qualified constant, we may need to add tail padding.
1672  if (auto AT = destType->getAs<AtomicType>()) {
1673  QualType destValueType = AT->getValueType();
1674  C = emitForMemory(CGM, C, destValueType);
1675 
1676  uint64_t innerSize = CGM.getContext().getTypeSize(destValueType);
1677  uint64_t outerSize = CGM.getContext().getTypeSize(destType);
1678  if (innerSize == outerSize)
1679  return C;
1680 
1681  assert(innerSize < outerSize && "emitted over-large constant for atomic");
1682  llvm::Constant *elts[] = {
1683  C,
1684  llvm::ConstantAggregateZero::get(
1685  llvm::ArrayType::get(CGM.Int8Ty, (outerSize - innerSize) / 8))
1686  };
1687  return llvm::ConstantStruct::getAnon(elts);
1688  }
1689 
1690  // Zero-extend bool.
1691  if (C->getType()->isIntegerTy(1)) {
1692  llvm::Type *boolTy = CGM.getTypes().ConvertTypeForMem(destType);
1693  return llvm::ConstantExpr::getZExt(C, boolTy);
1694  }
1695 
1696  return C;
1697 }
1698 
1699 llvm::Constant *ConstantEmitter::tryEmitPrivate(const Expr *E,
1700  QualType destType) {
1701  Expr::EvalResult Result;
1702 
1703  bool Success = false;
1704 
1705  if (destType->isReferenceType())
1706  Success = E->EvaluateAsLValue(Result, CGM.getContext());
1707  else
1708  Success = E->EvaluateAsRValue(Result, CGM.getContext(), InConstantContext);
1709 
1710  llvm::Constant *C;
1711  if (Success && !Result.HasSideEffects)
1712  C = tryEmitPrivate(Result.Val, destType);
1713  else
1714  C = ConstExprEmitter(*this).Visit(const_cast<Expr*>(E), destType);
1715 
1716  return C;
1717 }
1718 
1719 llvm::Constant *CodeGenModule::getNullPointer(llvm::PointerType *T, QualType QT) {
1720  return getTargetCodeGenInfo().getNullPointer(*this, T, QT);
1721 }
1722 
1723 namespace {
1724 /// A struct which can be used to peephole certain kinds of finalization
1725 /// that normally happen during l-value emission.
1726 struct ConstantLValue {
1727  llvm::Constant *Value;
1728  bool HasOffsetApplied;
1729 
1730  /*implicit*/ ConstantLValue(llvm::Constant *value,
1731  bool hasOffsetApplied = false)
1732  : Value(value), HasOffsetApplied(hasOffsetApplied) {}
1733 
1734  /*implicit*/ ConstantLValue(ConstantAddress address)
1735  : ConstantLValue(address.getPointer()) {}
1736 };
1737 
1738 /// A helper class for emitting constant l-values.
1739 class ConstantLValueEmitter : public ConstStmtVisitor<ConstantLValueEmitter,
1740  ConstantLValue> {
1741  CodeGenModule &CGM;
1742  ConstantEmitter &Emitter;
1743  const APValue &Value;
1744  QualType DestType;
1745 
1746  // Befriend StmtVisitorBase so that we don't have to expose Visit*.
1747  friend StmtVisitorBase;
1748 
1749 public:
1750  ConstantLValueEmitter(ConstantEmitter &emitter, const APValue &value,
1751  QualType destType)
1752  : CGM(emitter.CGM), Emitter(emitter), Value(value), DestType(destType) {}
1753 
1754  llvm::Constant *tryEmit();
1755 
1756 private:
1757  llvm::Constant *tryEmitAbsolute(llvm::Type *destTy);
1758  ConstantLValue tryEmitBase(const APValue::LValueBase &base);
1759 
1760  ConstantLValue VisitStmt(const Stmt *S) { return nullptr; }
1761  ConstantLValue VisitConstantExpr(const ConstantExpr *E);
1762  ConstantLValue VisitCompoundLiteralExpr(const CompoundLiteralExpr *E);
1763  ConstantLValue VisitStringLiteral(const StringLiteral *E);
1764  ConstantLValue VisitObjCBoxedExpr(const ObjCBoxedExpr *E);
1765  ConstantLValue VisitObjCEncodeExpr(const ObjCEncodeExpr *E);
1766  ConstantLValue VisitObjCStringLiteral(const ObjCStringLiteral *E);
1767  ConstantLValue VisitPredefinedExpr(const PredefinedExpr *E);
1768  ConstantLValue VisitAddrLabelExpr(const AddrLabelExpr *E);
1769  ConstantLValue VisitCallExpr(const CallExpr *E);
1770  ConstantLValue VisitBlockExpr(const BlockExpr *E);
1771  ConstantLValue VisitCXXTypeidExpr(const CXXTypeidExpr *E);
1772  ConstantLValue VisitCXXUuidofExpr(const CXXUuidofExpr *E);
1773  ConstantLValue VisitMaterializeTemporaryExpr(
1774  const MaterializeTemporaryExpr *E);
1775 
1776  bool hasNonZeroOffset() const {
1777  return !Value.getLValueOffset().isZero();
1778  }
1779 
1780  /// Return the value offset.
1781  llvm::Constant *getOffset() {
1782  return llvm::ConstantInt::get(CGM.Int64Ty,
1783  Value.getLValueOffset().getQuantity());
1784  }
1785 
1786  /// Apply the value offset to the given constant.
1787  llvm::Constant *applyOffset(llvm::Constant *C) {
1788  if (!hasNonZeroOffset())
1789  return C;
1790 
1791  llvm::Type *origPtrTy = C->getType();
1792  unsigned AS = origPtrTy->getPointerAddressSpace();
1793  llvm::Type *charPtrTy = CGM.Int8Ty->getPointerTo(AS);
1794  C = llvm::ConstantExpr::getBitCast(C, charPtrTy);
1795  C = llvm::ConstantExpr::getGetElementPtr(CGM.Int8Ty, C, getOffset());
1796  C = llvm::ConstantExpr::getPointerCast(C, origPtrTy);
1797  return C;
1798  }
1799 };
1800 
1801 }
1802 
1803 llvm::Constant *ConstantLValueEmitter::tryEmit() {
1804  const APValue::LValueBase &base = Value.getLValueBase();
1805 
1806  // The destination type should be a pointer or reference
1807  // type, but it might also be a cast thereof.
1808  //
1809  // FIXME: the chain of casts required should be reflected in the APValue.
1810  // We need this in order to correctly handle things like a ptrtoint of a
1811  // non-zero null pointer and addrspace casts that aren't trivially
1812  // represented in LLVM IR.
1813  auto destTy = CGM.getTypes().ConvertTypeForMem(DestType);
1814  assert(isa<llvm::IntegerType>(destTy) || isa<llvm::PointerType>(destTy));
1815 
1816  // If there's no base at all, this is a null or absolute pointer,
1817  // possibly cast back to an integer type.
1818  if (!base) {
1819  return tryEmitAbsolute(destTy);
1820  }
1821 
1822  // Otherwise, try to emit the base.
1823  ConstantLValue result = tryEmitBase(base);
1824 
1825  // If that failed, we're done.
1826  llvm::Constant *value = result.Value;
1827  if (!value) return nullptr;
1828 
1829  // Apply the offset if necessary and not already done.
1830  if (!result.HasOffsetApplied) {
1831  value = applyOffset(value);
1832  }
1833 
1834  // Convert to the appropriate type; this could be an lvalue for
1835  // an integer. FIXME: performAddrSpaceCast
1836  if (isa<llvm::PointerType>(destTy))
1837  return llvm::ConstantExpr::getPointerCast(value, destTy);
1838 
1839  return llvm::ConstantExpr::getPtrToInt(value, destTy);
1840 }
1841 
1842 /// Try to emit an absolute l-value, such as a null pointer or an integer
1843 /// bitcast to pointer type.
1844 llvm::Constant *
1845 ConstantLValueEmitter::tryEmitAbsolute(llvm::Type *destTy) {
1846  // If we're producing a pointer, this is easy.
1847  auto destPtrTy = cast<llvm::PointerType>(destTy);
1848  if (Value.isNullPointer()) {
1849  // FIXME: integer offsets from non-zero null pointers.
1850  return CGM.getNullPointer(destPtrTy, DestType);
1851  }
1852 
1853  // Convert the integer to a pointer-sized integer before converting it
1854  // to a pointer.
1855  // FIXME: signedness depends on the original integer type.
1856  auto intptrTy = CGM.getDataLayout().getIntPtrType(destPtrTy);
1857  llvm::Constant *C;
1858  C = llvm::ConstantExpr::getIntegerCast(getOffset(), intptrTy,
1859  /*isSigned*/ false);
1860  C = llvm::ConstantExpr::getIntToPtr(C, destPtrTy);
1861  return C;
1862 }
1863 
1864 ConstantLValue
1865 ConstantLValueEmitter::tryEmitBase(const APValue::LValueBase &base) {
1866  // Handle values.
1867  if (const ValueDecl *D = base.dyn_cast<const ValueDecl*>()) {
1868  if (D->hasAttr<WeakRefAttr>())
1869  return CGM.GetWeakRefReference(D).getPointer();
1870 
1871  if (auto FD = dyn_cast<FunctionDecl>(D))
1872  return CGM.GetAddrOfFunction(FD);
1873 
1874  if (auto VD = dyn_cast<VarDecl>(D)) {
1875  // We can never refer to a variable with local storage.
1876  if (!VD->hasLocalStorage()) {
1877  if (VD->isFileVarDecl() || VD->hasExternalStorage())
1878  return CGM.GetAddrOfGlobalVar(VD);
1879 
1880  if (VD->isLocalVarDecl()) {
1881  return CGM.getOrCreateStaticVarDecl(
1882  *VD, CGM.getLLVMLinkageVarDefinition(VD, /*IsConstant=*/false));
1883  }
1884  }
1885  }
1886 
1887  return nullptr;
1888  }
1889 
1890  // Handle typeid(T).
1891  if (TypeInfoLValue TI = base.dyn_cast<TypeInfoLValue>()) {
1892  llvm::Type *StdTypeInfoPtrTy =
1893  CGM.getTypes().ConvertType(base.getTypeInfoType())->getPointerTo();
1894  llvm::Constant *TypeInfo =
1895  CGM.GetAddrOfRTTIDescriptor(QualType(TI.getType(), 0));
1896  if (TypeInfo->getType() != StdTypeInfoPtrTy)
1897  TypeInfo = llvm::ConstantExpr::getBitCast(TypeInfo, StdTypeInfoPtrTy);
1898  return TypeInfo;
1899  }
1900 
1901  // Otherwise, it must be an expression.
1902  return Visit(base.get<const Expr*>());
1903 }
1904 
1905 ConstantLValue
1906 ConstantLValueEmitter::VisitConstantExpr(const ConstantExpr *E) {
1907  return Visit(E->getSubExpr());
1908 }
1909 
1910 ConstantLValue
1911 ConstantLValueEmitter::VisitCompoundLiteralExpr(const CompoundLiteralExpr *E) {
1912  return tryEmitGlobalCompoundLiteral(CGM, Emitter.CGF, E);
1913 }
1914 
1915 ConstantLValue
1916 ConstantLValueEmitter::VisitStringLiteral(const StringLiteral *E) {
1917  return CGM.GetAddrOfConstantStringFromLiteral(E);
1918 }
1919 
1920 ConstantLValue
1921 ConstantLValueEmitter::VisitObjCEncodeExpr(const ObjCEncodeExpr *E) {
1923 }
1924 
1925 static ConstantLValue emitConstantObjCStringLiteral(const StringLiteral *S,
1926  QualType T,
1927  CodeGenModule &CGM) {
1928  auto C = CGM.getObjCRuntime().GenerateConstantString(S);
1929  return C.getElementBitCast(CGM.getTypes().ConvertTypeForMem(T));
1930 }
1931 
1932 ConstantLValue
1933 ConstantLValueEmitter::VisitObjCStringLiteral(const ObjCStringLiteral *E) {
1934  return emitConstantObjCStringLiteral(E->getString(), E->getType(), CGM);
1935 }
1936 
1937 ConstantLValue
1938 ConstantLValueEmitter::VisitObjCBoxedExpr(const ObjCBoxedExpr *E) {
1939  assert(E->isExpressibleAsConstantInitializer() &&
1940  "this boxed expression can't be emitted as a compile-time constant");
1941  auto *SL = cast<StringLiteral>(E->getSubExpr()->IgnoreParenCasts());
1942  return emitConstantObjCStringLiteral(SL, E->getType(), CGM);
1943 }
1944 
1945 ConstantLValue
1946 ConstantLValueEmitter::VisitPredefinedExpr(const PredefinedExpr *E) {
1948 }
1949 
1950 ConstantLValue
1951 ConstantLValueEmitter::VisitAddrLabelExpr(const AddrLabelExpr *E) {
1952  assert(Emitter.CGF && "Invalid address of label expression outside function");
1953  llvm::Constant *Ptr = Emitter.CGF->GetAddrOfLabel(E->getLabel());
1954  Ptr = llvm::ConstantExpr::getBitCast(Ptr,
1955  CGM.getTypes().ConvertType(E->getType()));
1956  return Ptr;
1957 }
1958 
1959 ConstantLValue
1960 ConstantLValueEmitter::VisitCallExpr(const CallExpr *E) {
1961  unsigned builtin = E->getBuiltinCallee();
1962  if (builtin != Builtin::BI__builtin___CFStringMakeConstantString &&
1963  builtin != Builtin::BI__builtin___NSStringMakeConstantString)
1964  return nullptr;
1965 
1966  auto literal = cast<StringLiteral>(E->getArg(0)->IgnoreParenCasts());
1967  if (builtin == Builtin::BI__builtin___NSStringMakeConstantString) {
1968  return CGM.getObjCRuntime().GenerateConstantString(literal);
1969  } else {
1970  // FIXME: need to deal with UCN conversion issues.
1971  return CGM.GetAddrOfConstantCFString(literal);
1972  }
1973 }
1974 
1975 ConstantLValue
1976 ConstantLValueEmitter::VisitBlockExpr(const BlockExpr *E) {
1977  StringRef functionName;
1978  if (auto CGF = Emitter.CGF)
1979  functionName = CGF->CurFn->getName();
1980  else
1981  functionName = "global";
1982 
1983  return CGM.GetAddrOfGlobalBlock(E, functionName);
1984 }
1985 
1986 ConstantLValue
1987 ConstantLValueEmitter::VisitCXXTypeidExpr(const CXXTypeidExpr *E) {
1988  QualType T;
1989  if (E->isTypeOperand())
1990  T = E->getTypeOperand(CGM.getContext());
1991  else
1992  T = E->getExprOperand()->getType();
1993  return CGM.GetAddrOfRTTIDescriptor(T);
1994 }
1995 
1996 ConstantLValue
1997 ConstantLValueEmitter::VisitCXXUuidofExpr(const CXXUuidofExpr *E) {
1998  return CGM.GetAddrOfUuidDescriptor(E);
1999 }
2000 
2001 ConstantLValue
2002 ConstantLValueEmitter::VisitMaterializeTemporaryExpr(
2003  const MaterializeTemporaryExpr *E) {
2004  assert(E->getStorageDuration() == SD_Static);
2005  SmallVector<const Expr *, 2> CommaLHSs;
2007  const Expr *Inner =
2008  E->getSubExpr()->skipRValueSubobjectAdjustments(CommaLHSs, Adjustments);
2009  return CGM.GetAddrOfGlobalTemporary(E, Inner);
2010 }
2011 
2013  QualType DestType) {
2014  switch (Value.getKind()) {
2015  case APValue::None:
2017  // Out-of-lifetime and indeterminate values can be modeled as 'undef'.
2018  return llvm::UndefValue::get(CGM.getTypes().ConvertType(DestType));
2019  case APValue::LValue:
2020  return ConstantLValueEmitter(*this, Value, DestType).tryEmit();
2021  case APValue::Int:
2022  return llvm::ConstantInt::get(CGM.getLLVMContext(), Value.getInt());
2023  case APValue::FixedPoint:
2024  return llvm::ConstantInt::get(CGM.getLLVMContext(),
2025  Value.getFixedPoint().getValue());
2026  case APValue::ComplexInt: {
2027  llvm::Constant *Complex[2];
2028 
2029  Complex[0] = llvm::ConstantInt::get(CGM.getLLVMContext(),
2030  Value.getComplexIntReal());
2031  Complex[1] = llvm::ConstantInt::get(CGM.getLLVMContext(),
2032  Value.getComplexIntImag());
2033 
2034  // FIXME: the target may want to specify that this is packed.
2035  llvm::StructType *STy =
2036  llvm::StructType::get(Complex[0]->getType(), Complex[1]->getType());
2037  return llvm::ConstantStruct::get(STy, Complex);
2038  }
2039  case APValue::Float: {
2040  const llvm::APFloat &Init = Value.getFloat();
2041  if (&Init.getSemantics() == &llvm::APFloat::IEEEhalf() &&
2042  !CGM.getContext().getLangOpts().NativeHalfType &&
2044  return llvm::ConstantInt::get(CGM.getLLVMContext(),
2045  Init.bitcastToAPInt());
2046  else
2047  return llvm::ConstantFP::get(CGM.getLLVMContext(), Init);
2048  }
2049  case APValue::ComplexFloat: {
2050  llvm::Constant *Complex[2];
2051 
2052  Complex[0] = llvm::ConstantFP::get(CGM.getLLVMContext(),
2053  Value.getComplexFloatReal());
2054  Complex[1] = llvm::ConstantFP::get(CGM.getLLVMContext(),
2055  Value.getComplexFloatImag());
2056 
2057  // FIXME: the target may want to specify that this is packed.
2058  llvm::StructType *STy =
2059  llvm::StructType::get(Complex[0]->getType(), Complex[1]->getType());
2060  return llvm::ConstantStruct::get(STy, Complex);
2061  }
2062  case APValue::Vector: {
2063  unsigned NumElts = Value.getVectorLength();
2065 
2066  for (unsigned I = 0; I != NumElts; ++I) {
2067  const APValue &Elt = Value.getVectorElt(I);
2068  if (Elt.isInt())
2069  Inits[I] = llvm::ConstantInt::get(CGM.getLLVMContext(), Elt.getInt());
2070  else if (Elt.isFloat())
2071  Inits[I] = llvm::ConstantFP::get(CGM.getLLVMContext(), Elt.getFloat());
2072  else
2073  llvm_unreachable("unsupported vector element type");
2074  }
2075  return llvm::ConstantVector::get(Inits);
2076  }
2077  case APValue::AddrLabelDiff: {
2078  const AddrLabelExpr *LHSExpr = Value.getAddrLabelDiffLHS();
2079  const AddrLabelExpr *RHSExpr = Value.getAddrLabelDiffRHS();
2080  llvm::Constant *LHS = tryEmitPrivate(LHSExpr, LHSExpr->getType());
2081  llvm::Constant *RHS = tryEmitPrivate(RHSExpr, RHSExpr->getType());
2082  if (!LHS || !RHS) return nullptr;
2083 
2084  // Compute difference
2085  llvm::Type *ResultType = CGM.getTypes().ConvertType(DestType);
2086  LHS = llvm::ConstantExpr::getPtrToInt(LHS, CGM.IntPtrTy);
2087  RHS = llvm::ConstantExpr::getPtrToInt(RHS, CGM.IntPtrTy);
2088  llvm::Constant *AddrLabelDiff = llvm::ConstantExpr::getSub(LHS, RHS);
2089 
2090  // LLVM is a bit sensitive about the exact format of the
2091  // address-of-label difference; make sure to truncate after
2092  // the subtraction.
2093  return llvm::ConstantExpr::getTruncOrBitCast(AddrLabelDiff, ResultType);
2094  }
2095  case APValue::Struct:
2096  case APValue::Union:
2097  return ConstStructBuilder::BuildStruct(*this, Value, DestType);
2098  case APValue::Array: {
2099  const ConstantArrayType *CAT =
2100  CGM.getContext().getAsConstantArrayType(DestType);
2101  unsigned NumElements = Value.getArraySize();
2102  unsigned NumInitElts = Value.getArrayInitializedElts();
2103 
2104  // Emit array filler, if there is one.
2105  llvm::Constant *Filler = nullptr;
2106  if (Value.hasArrayFiller()) {
2107  Filler = tryEmitAbstractForMemory(Value.getArrayFiller(),
2108  CAT->getElementType());
2109  if (!Filler)
2110  return nullptr;
2111  }
2112 
2113  // Emit initializer elements.
2115  if (Filler && Filler->isNullValue())
2116  Elts.reserve(NumInitElts + 1);
2117  else
2118  Elts.reserve(NumElements);
2119 
2120  llvm::Type *CommonElementType = nullptr;
2121  for (unsigned I = 0; I < NumInitElts; ++I) {
2122  llvm::Constant *C = tryEmitPrivateForMemory(
2123  Value.getArrayInitializedElt(I), CAT->getElementType());
2124  if (!C) return nullptr;
2125 
2126  if (I == 0)
2127  CommonElementType = C->getType();
2128  else if (C->getType() != CommonElementType)
2129  CommonElementType = nullptr;
2130  Elts.push_back(C);
2131  }
2132 
2133  // This means that the array type is probably "IncompleteType" or some
2134  // type that is not ConstantArray.
2135  if (CAT == nullptr && CommonElementType == nullptr && !NumInitElts) {
2136  const ArrayType *AT = CGM.getContext().getAsArrayType(DestType);
2137  CommonElementType = CGM.getTypes().ConvertType(AT->getElementType());
2138  llvm::ArrayType *AType = llvm::ArrayType::get(CommonElementType,
2139  NumElements);
2140  return llvm::ConstantAggregateZero::get(AType);
2141  }
2142 
2143  llvm::ArrayType *Desired =
2144  cast<llvm::ArrayType>(CGM.getTypes().ConvertType(DestType));
2145  return EmitArrayConstant(CGM, Desired, CommonElementType, NumElements, Elts,
2146  Filler);
2147  }
2149  return CGM.getCXXABI().EmitMemberPointer(Value, DestType);
2150  }
2151  llvm_unreachable("Unknown APValue kind");
2152 }
2153 
2155  const CompoundLiteralExpr *E) {
2156  return EmittedCompoundLiterals.lookup(E);
2157 }
2158 
2160  const CompoundLiteralExpr *CLE, llvm::GlobalVariable *GV) {
2161  bool Ok = EmittedCompoundLiterals.insert(std::make_pair(CLE, GV)).second;
2162  (void)Ok;
2163  assert(Ok && "CLE has already been emitted!");
2164 }
2165 
2168  assert(E->isFileScope() && "not a file-scope compound literal expr");
2169  return tryEmitGlobalCompoundLiteral(*this, nullptr, E);
2170 }
2171 
2172 llvm::Constant *
2174  // Member pointer constants always have a very particular form.
2175  const MemberPointerType *type = cast<MemberPointerType>(uo->getType());
2176  const ValueDecl *decl = cast<DeclRefExpr>(uo->getSubExpr())->getDecl();
2177 
2178  // A member function pointer.
2179  if (const CXXMethodDecl *method = dyn_cast<CXXMethodDecl>(decl))
2180  return getCXXABI().EmitMemberFunctionPointer(method);
2181 
2182  // Otherwise, a member data pointer.
2183  uint64_t fieldOffset = getContext().getFieldOffset(decl);
2184  CharUnits chars = getContext().toCharUnitsFromBits((int64_t) fieldOffset);
2185  return getCXXABI().EmitMemberDataPointer(type, chars);
2186 }
2187 
2188 static llvm::Constant *EmitNullConstantForBase(CodeGenModule &CGM,
2189  llvm::Type *baseType,
2190  const CXXRecordDecl *base);
2191 
2192 static llvm::Constant *EmitNullConstant(CodeGenModule &CGM,
2193  const RecordDecl *record,
2194  bool asCompleteObject) {
2195  const CGRecordLayout &layout = CGM.getTypes().getCGRecordLayout(record);
2196  llvm::StructType *structure =
2197  (asCompleteObject ? layout.getLLVMType()
2198  : layout.getBaseSubobjectLLVMType());
2199 
2200  unsigned numElements = structure->getNumElements();
2201  std::vector<llvm::Constant *> elements(numElements);
2202 
2203  auto CXXR = dyn_cast<CXXRecordDecl>(record);
2204  // Fill in all the bases.
2205  if (CXXR) {
2206  for (const auto &I : CXXR->bases()) {
2207  if (I.isVirtual()) {
2208  // Ignore virtual bases; if we're laying out for a complete
2209  // object, we'll lay these out later.
2210  continue;
2211  }
2212 
2213  const CXXRecordDecl *base =
2214  cast<CXXRecordDecl>(I.getType()->castAs<RecordType>()->getDecl());
2215 
2216  // Ignore empty bases.
2217  if (base->isEmpty() ||
2219  .isZero())
2220  continue;
2221 
2222  unsigned fieldIndex = layout.getNonVirtualBaseLLVMFieldNo(base);
2223  llvm::Type *baseType = structure->getElementType(fieldIndex);
2224  elements[fieldIndex] = EmitNullConstantForBase(CGM, baseType, base);
2225  }
2226  }
2227 
2228  // Fill in all the fields.
2229  for (const auto *Field : record->fields()) {
2230  // Fill in non-bitfields. (Bitfields always use a zero pattern, which we
2231  // will fill in later.)
2232  if (!Field->isBitField() && !Field->isZeroSize(CGM.getContext())) {
2233  unsigned fieldIndex = layout.getLLVMFieldNo(Field);
2234  elements[fieldIndex] = CGM.EmitNullConstant(Field->getType());
2235  }
2236 
2237  // For unions, stop after the first named field.
2238  if (record->isUnion()) {
2239  if (Field->getIdentifier())
2240  break;
2241  if (const auto *FieldRD = Field->getType()->getAsRecordDecl())
2242  if (FieldRD->findFirstNamedDataMember())
2243  break;
2244  }
2245  }
2246 
2247  // Fill in the virtual bases, if we're working with the complete object.
2248  if (CXXR && asCompleteObject) {
2249  for (const auto &I : CXXR->vbases()) {
2250  const CXXRecordDecl *base =
2251  cast<CXXRecordDecl>(I.getType()->castAs<RecordType>()->getDecl());
2252 
2253  // Ignore empty bases.
2254  if (base->isEmpty())
2255  continue;
2256 
2257  unsigned fieldIndex = layout.getVirtualBaseIndex(base);
2258 
2259  // We might have already laid this field out.
2260  if (elements[fieldIndex]) continue;
2261 
2262  llvm::Type *baseType = structure->getElementType(fieldIndex);
2263  elements[fieldIndex] = EmitNullConstantForBase(CGM, baseType, base);
2264  }
2265  }
2266 
2267  // Now go through all other fields and zero them out.
2268  for (unsigned i = 0; i != numElements; ++i) {
2269  if (!elements[i])
2270  elements[i] = llvm::Constant::getNullValue(structure->getElementType(i));
2271  }
2272 
2273  return llvm::ConstantStruct::get(structure, elements);
2274 }
2275 
2276 /// Emit the null constant for a base subobject.
2277 static llvm::Constant *EmitNullConstantForBase(CodeGenModule &CGM,
2278  llvm::Type *baseType,
2279  const CXXRecordDecl *base) {
2280  const CGRecordLayout &baseLayout = CGM.getTypes().getCGRecordLayout(base);
2281 
2282  // Just zero out bases that don't have any pointer to data members.
2283  if (baseLayout.isZeroInitializableAsBase())
2284  return llvm::Constant::getNullValue(baseType);
2285 
2286  // Otherwise, we can just use its null constant.
2287  return EmitNullConstant(CGM, base, /*asCompleteObject=*/false);
2288 }
2289 
2291  QualType T) {
2292  return emitForMemory(CGM, CGM.EmitNullConstant(T), T);
2293 }
2294 
2296  if (T->getAs<PointerType>())
2297  return getNullPointer(
2298  cast<llvm::PointerType>(getTypes().ConvertTypeForMem(T)), T);
2299 
2300  if (getTypes().isZeroInitializable(T))
2301  return llvm::Constant::getNullValue(getTypes().ConvertTypeForMem(T));
2302 
2303  if (const ConstantArrayType *CAT = Context.getAsConstantArrayType(T)) {
2304  llvm::ArrayType *ATy =
2305  cast<llvm::ArrayType>(getTypes().ConvertTypeForMem(T));
2306 
2307  QualType ElementTy = CAT->getElementType();
2308 
2309  llvm::Constant *Element =
2310  ConstantEmitter::emitNullForMemory(*this, ElementTy);
2311  unsigned NumElements = CAT->getSize().getZExtValue();
2312  SmallVector<llvm::Constant *, 8> Array(NumElements, Element);
2313  return llvm::ConstantArray::get(ATy, Array);
2314  }
2315 
2316  if (const RecordType *RT = T->getAs<RecordType>())
2317  return ::EmitNullConstant(*this, RT->getDecl(), /*complete object*/ true);
2318 
2319  assert(T->isMemberDataPointerType() &&
2320  "Should only see pointers to data members here!");
2321 
2322  return getCXXABI().EmitNullMemberPointer(T->castAs<MemberPointerType>());
2323 }
2324 
2325 llvm::Constant *
2327  return ::EmitNullConstant(*this, Record, false);
2328 }
const llvm::DataLayout & getDataLayout() const
const Expr * getSubExpr() const
Definition: Expr.h:963
const internal::VariadicAllOfMatcher< Type > type
Matches Types in the clang AST.
Defines the clang::ASTContext interface.
CharUnits alignTo(const CharUnits &Align) const
alignTo - Returns the next integer (mod 2**64) that is greater than or equal to this quantity and is ...
Definition: CharUnits.h:188
Expr * getChosenSubExpr() const
getChosenSubExpr - Return the subexpression chosen according to the condition.
Definition: Expr.h:4171
CodeGenFunction *const CGF
virtual llvm::Constant * EmitMemberPointer(const APValue &MP, QualType MPT)
Create a member pointer for the given member pointer constant.
Definition: CGCXXABI.cpp:113
PointerType - C99 6.7.5.1 - Pointer Declarators.
Definition: Type.h:2614
A (possibly-)qualified type.
Definition: Type.h:654
Static storage duration.
Definition: Specifiers.h:310
bool isArrayType() const
Definition: Type.h:6570
llvm::Constant * emitForInitializer(const APValue &value, LangAS destAddrSpace, QualType destType)
Expr * getArg(unsigned Arg)
getArg - Return the specified argument.
Definition: Expr.h:2702
const Expr * skipRValueSubobjectAdjustments(SmallVectorImpl< const Expr *> &CommaLHS, SmallVectorImpl< SubobjectAdjustment > &Adjustments) const
Walk outwards from an expression we want to bind a reference to and find the expression whose lifetim...
Definition: Expr.cpp:76
ConstStmtVisitor - This class implements a simple visitor for Stmt subclasses.
Definition: StmtVisitor.h:193
CGRecordLayout - This class handles struct and union layout info while lowering AST types to LLVM typ...
bool isMemberDataPointerType() const
Definition: Type.h:6563
llvm::APSInt getValue() const
Definition: FixedPoint.h:110
Expr * getResultExpr()
Return the result expression of this controlling expression.
Definition: Expr.h:5426
llvm::Constant * getMemberPointerConstant(const UnaryOperator *e)
llvm::LLVMContext & getLLVMContext()
const Expr * getInit(unsigned Init) const
Definition: Expr.h:4451
ConstantAddress GetAddrOfConstantStringFromObjCEncode(const ObjCEncodeExpr *)
Return a pointer to a constant array for the given ObjCEncodeExpr node.
const ASTRecordLayout & getASTRecordLayout(const RecordDecl *D) const
Get or compute information about the layout of the specified record (struct/union/class) D...
Stmt - This represents one statement.
Definition: Stmt.h:66
llvm::Constant * tryEmitForInitializer(const VarDecl &D)
Try to emit the initiaizer of the given declaration as an abstract constant.
QualType getPointeeType() const
If this is a pointer, ObjC object pointer, or block pointer, this returns the respective pointee...
Definition: Type.cpp:557
CharUnits getBaseClassOffset(const CXXRecordDecl *Base) const
getBaseClassOffset - Get the offset, in chars, for the given base class.
Definition: RecordLayout.h:232
bool isRecordType() const
Definition: Type.h:6594
QualType getQualifiedType(SplitQualType split) const
Un-split a SplitQualType.
Definition: ASTContext.h:1958
Decl - This represents one declaration (or definition), e.g.
Definition: DeclBase.h:88
llvm::Constant * emitForMemory(llvm::Constant *C, QualType T)
bool isTransparent() const
Is this a transparent initializer list (that is, an InitListExpr that is purely syntactic, and whose semantics are that of the sole contained initializer)?
Definition: Expr.cpp:2303
ParenExpr - This represents a parethesized expression, e.g.
Definition: Expr.h:1994
The base class of the type hierarchy.
Definition: Type.h:1450
Represents an array type, per C99 6.7.5.2 - Array Declarators.
Definition: Type.h:2889
Represents a call to a C++ constructor.
Definition: ExprCXX.h:1422
bool isZero() const
isZero - Test whether the quantity equals zero.
Definition: CharUnits.h:116
const TargetInfo & getTargetInfo() const
Definition: ASTContext.h:707
The l-value was an access to a declared entity or something equivalently strong, like the address of ...
llvm::IntegerType * Int8Ty
i8, i16, i32, and i64
Represents a C++ constructor within a class.
Definition: DeclCXX.h:2383
Represents a prvalue temporary that is written into memory so that a reference can bind to it...
Definition: ExprCXX.h:4419
const AddrLabelExpr * getAddrLabelDiffLHS() const
Definition: APValue.h:534
QualType getElementType() const
Definition: Type.h:2910
bool isDefaultConstructor() const
Whether this constructor is a default constructor (C++ [class.ctor]p5), which can be used to default-...
Definition: DeclCXX.cpp:2544
llvm::Constant * tryEmitPrivateForVarInit(const VarDecl &D)
Represents a variable declaration or definition.
Definition: Decl.h:820
CompoundLiteralExpr - [C99 6.5.2.5].
Definition: Expr.h:3077
const internal::VariadicDynCastAllOfMatcher< Stmt, Expr > expr
Matches expressions.
APFloat & getComplexFloatReal()
Definition: APValue.h:426
const T * getAs() const
Member-template getAs<specific type>&#39;.
Definition: Type.h:7002
LangAS
Defines the address space values used by the address space qualifier of QualType. ...
Definition: AddressSpaces.h:25
QualType getTypeInfoType() const
Definition: APValue.cpp:70
llvm::Type * ConvertTypeForMem(QualType T)
ConvertTypeForMem - Convert type T into a llvm::Type.
Expr * getExprOperand() const
Definition: ExprCXX.h:821
Represents an expression – generally a full-expression – that introduces cleanups to be run at the ...
Definition: ExprCXX.h:3306
bool isZeroInitializableAsBase() const
Check whether this struct can be C++ zero-initialized with a zeroinitializer when considered as a bas...
IdentifierInfo * getIdentifier() const
Get the identifier that names this declaration, if there is one.
Definition: Decl.h:244
Represents a struct/union/class.
Definition: Decl.h:3748
bool isEmpty() const
Determine whether this is an empty class in the sense of (C++11 [meta.unary.prop]).
Definition: DeclCXX.h:1099
bool cleanupsHaveSideEffects() const
Definition: ExprCXX.h:3344
CodeGenFunction - This class organizes the per-function state that is used while generating LLVM code...
virtual llvm::Constant * getVTableAddressPointForConstExpr(BaseSubobject Base, const CXXRecordDecl *VTableClass)=0
Get the address point of the vtable for the given base subobject while building a constexpr...
llvm::Type * ConvertType(QualType T)
ConvertType - Convert type T into a llvm::Type.
Holds long-lived AST nodes (such as types and decls) that can be referred to throughout the semantic ...
Definition: ASTContext.h:168
llvm::Constant * tryEmitAbstractForInitializer(const VarDecl &D)
Try to emit the initializer of the given declaration as an abstract constant.
bool isFileScope() const
Definition: Expr.h:3107
field_range fields() const
Definition: Decl.h:3963
Represents a member of a struct/union/class.
Definition: Decl.h:2729
StringLiteral * getString()
Definition: ExprObjC.h:62
unsigned getNonVirtualBaseLLVMFieldNo(const CXXRecordDecl *RD) const
bool isReferenceType() const
Definition: Type.h:6516
__SIZE_TYPE__ size_t
The unsigned integer type of the result of the sizeof operator.
Definition: opencl-c-base.h:40
unsigned getArraySize() const
Definition: APValue.h:490
static CharUnits Zero()
Zero - Construct a CharUnits quantity of zero.
Definition: CharUnits.h:53
__DEVICE__ int max(int __a, int __b)
Expr * getSubExpr()
Definition: Expr.h:3202
Symbolic representation of typeid(T) for some type T.
Definition: APValue.h:37
i32 captured_struct **param SharedsTy A type which contains references the shared variables *param Shareds Context with the list of shared variables from the p *TaskFunction *param Data Additional data for task generation like final * state
bool isFloat() const
Definition: APValue.h:362
bool GE(InterpState &S, CodePtr OpPC)
Definition: Interp.h:252
llvm::Constant * GetConstantArrayFromStringLiteral(const StringLiteral *E)
Return a constant array for the given string.
Describes an C or C++ initializer list.
Definition: Expr.h:4403
A C++ typeid expression (C++ [expr.typeid]), which gets the type_info that corresponds to the supplie...
Definition: ExprCXX.h:764
bool isBitField() const
Determines whether this field is a bitfield.
Definition: Decl.h:2807
CharUnits - This is an opaque type for sizes expressed in character units.
Definition: CharUnits.h:38
APValue Val
Val - This is the value the expression can be folded to.
Definition: Expr.h:588
llvm::Align getAsAlign() const
getAsAlign - Returns Quantity as a valid llvm::Align, Beware llvm::Align assumes power of two 8-bit b...
Definition: CharUnits.h:183
llvm::Constant * tryEmitPrivate(const Expr *E, QualType T)
llvm::StructType * getBaseSubobjectLLVMType() const
Return the "base subobject" LLVM type associated with this record.
Expr * IgnoreParenCasts() LLVM_READONLY
Skip past any parentheses and casts which might surround this expression until reaching a fixed point...
Definition: Expr.cpp:3000
ObjCStringLiteral, used for Objective-C string literals i.e.
Definition: ExprObjC.h:50
field_iterator field_begin() const
Definition: Decl.cpp:4425
unsigned getBitWidthValue(const ASTContext &Ctx) const
Definition: Decl.cpp:4031
bool declaresSameEntity(const Decl *D1, const Decl *D2)
Determine whether two declarations declare the same entity.
Definition: DeclBase.h:1166
bool isInt() const
Definition: APValue.h:361
CastExpr - Base class for type casts, including both implicit casts (ImplicitCastExpr) and explicit c...
Definition: Expr.h:3150
bool Const(InterpState &S, CodePtr OpPC, const T &Arg)
Definition: Interp.h:294
APSInt & getComplexIntReal()
Definition: APValue.h:410
llvm::GlobalValue * getCurrentAddrPrivate()
Get the address of the current location.
virtual llvm::Value * performAddrSpaceCast(CodeGen::CodeGenFunction &CGF, llvm::Value *V, LangAS SrcAddr, LangAS DestAddr, llvm::Type *DestTy, bool IsNonNull=false) const
Perform address space cast of an expression of pointer type.
Definition: TargetInfo.cpp:447
bool isTypeConstant(QualType QTy, bool ExcludeCtorDtor)
isTypeConstant - Determine whether an object of this type can be emitted as a constant.
const Expr * getExpr() const
Get the initialization expression that will be used.
Definition: ExprCXX.h:1307
APValue & getVectorElt(unsigned I)
Definition: APValue.h:454
bool hasAttr() const
Definition: DeclBase.h:542
RecordDecl * getAsRecordDecl() const
Retrieves the RecordDecl this type refers to.
Definition: Type.cpp:1694
static CharUnits One()
One - Construct a CharUnits quantity of one.
Definition: CharUnits.h:58
ConstantAddress getElementBitCast(llvm::Type *ty) const
Definition: Address.h:92
const TargetCodeGenInfo & getTargetCodeGenInfo()
CXXConstructorDecl * getConstructor() const
Get the constructor that this expression will (ultimately) call.
Definition: ExprCXX.h:1494
APValue & getArrayFiller()
Definition: APValue.h:478
bool EvaluateAsLValue(EvalResult &Result, const ASTContext &Ctx, bool InConstantContext=false) const
EvaluateAsLValue - Evaluate an expression to see if we can fold it to an lvalue with link time known ...
llvm::Constant * getNullPointer(llvm::PointerType *T, QualType QT)
Get target specific null pointer.
InitListExpr * getUpdater() const
Definition: Expr.h:4995
QuantityType getQuantity() const
getQuantity - Get the raw integer representation of this quantity.
Definition: CharUnits.h:179
ConstantExpr - An expression that occurs in a constant context and optionally the result of evaluatin...
Definition: Expr.h:978
unsigned Offset
Definition: Format.cpp:1827
ASTRecordLayout - This class contains layout information for one RecordDecl, which is a struct/union/...
Definition: RecordLayout.h:38
bool hasArrayFiller() const
Definition: APValue.h:475
CGObjCRuntime & getObjCRuntime()
Return a reference to the configured Objective-C runtime.
Represent the declaration of a variable (in which case it is an lvalue) a function (in which case it ...
Definition: Decl.h:619
This represents one expression.
Definition: Expr.h:108
bool isCopyOrMoveConstructor(unsigned &TypeQuals) const
Determine whether this is a copy or move constructor.
Definition: DeclCXX.cpp:2564
bool hasLocalStorage() const
Returns true if a variable with function scope is a non-static local variable.
Definition: Decl.h:1045
llvm::Constant * GetAddrOfGlobalVar(const VarDecl *D, llvm::Type *Ty=nullptr, ForDefinition_t IsForDefinition=NotForDefinition)
Return the llvm::Constant for the address of the given global variable.
const T * castAs() const
Member-template castAs<specific type>.
Definition: Type.h:7067
Inits[]
Definition: OpenMPClause.h:150
BlockExpr - Adaptor class for mixing a BlockDecl with expressions.
Definition: Expr.h:5579
const internal::VariadicAllOfMatcher< Decl > decl
Matches declarations.
unsigned getNumInits() const
Definition: Expr.h:4433
field_iterator field_end() const
Definition: Decl.h:3966
CharUnits getTypeAlignInChars(QualType T) const
Return the ABI-specified alignment of a (complete) type T, in characters.
const CXXRecordDecl * getPrimaryBase() const
getPrimaryBase - Get the primary base for this record.
Definition: RecordLayout.h:217
static CharUnits fromQuantity(QuantityType Quantity)
fromQuantity - Construct a CharUnits quantity from a raw integer type.
Definition: CharUnits.h:63
QualType getType() const
Definition: Expr.h:137
llvm::GlobalValue::LinkageTypes getLLVMLinkageVarDefinition(const VarDecl *VD, bool IsConstant)
Returns LLVM linkage for a declarator.
APValue & getStructField(unsigned i)
Definition: APValue.h:507
StorageDuration getStorageDuration() const
Retrieve the storage duration for the materialized temporary.
Definition: ExprCXX.h:4444
QualType getEncodedType() const
Definition: ExprObjC.h:428
ConstantAddress GetAddrOfUuidDescriptor(const CXXUuidofExpr *E)
Get the address of a uuid descriptor .
UnaryOperator - This represents the unary-expression&#39;s (except sizeof and alignof), the postinc/postdec operators from postfix-expression, and various extensions.
Definition: Expr.h:2046
QualType getTypeOperand(ASTContext &Context) const
Retrieves the type operand of this typeid() expression after various required adjustments (removing r...
Definition: ExprCXX.cpp:147
Represents a reference to a non-type template parameter that has been substituted with a template arg...
Definition: ExprCXX.h:4209
APValue * evaluateValue() const
Attempt to evaluate the value of the initializer attached to this declaration, and produce notes expl...
Definition: Decl.cpp:2356
APSInt & getComplexIntImag()
Definition: APValue.h:418
bool isTrivial() const
Whether this function is "trivial" in some specialized C++ senses.
Definition: Decl.h:2122
const Expr * getSubExpr() const
Definition: Expr.h:2010
bool isUnionType() const
Definition: Type.cpp:527
ASTContext & getContext() const
const FieldDecl * getUnionField() const
Definition: APValue.h:518
ConstantAddress GetAddrOfGlobalTemporary(const MaterializeTemporaryExpr *E, const Expr *Inner)
Returns a pointer to a global variable representing a temporary with static or thread storage duratio...
unsigned getBuiltinCallee() const
getBuiltinCallee - If this is a call to a builtin, return the builtin ID of the callee.
Definition: Expr.cpp:1471
The l-value was considered opaque, so the alignment was determined from a type.
APValue & getStructBase(unsigned i)
Definition: APValue.h:503
virtual bool useFP16ConversionIntrinsics() const
Check whether llvm intrinsics such as llvm.convert.to.fp16 should be used to convert to and from __fp...
Definition: TargetInfo.h:754
uint64_t getFieldOffset(unsigned FieldNo) const
getFieldOffset - Get the offset of the given field index, in bits.
Definition: RecordLayout.h:190
static ConstantLValue emitConstantObjCStringLiteral(const StringLiteral *S, QualType T, CodeGenModule &CGM)
llvm::Constant * getOrCreateStaticVarDecl(const VarDecl &D, llvm::GlobalValue::LinkageTypes Linkage)
Definition: CGDecl.cpp:221
bool EvaluateAsRValue(EvalResult &Result, const ASTContext &Ctx, bool InConstantContext=false) const
EvaluateAsRValue - Return true if this is a constant which we can fold to an rvalue using any crazy t...
Expr * getBase() const
Definition: Expr.h:4992
APValue & getArrayInitializedElt(unsigned I)
Definition: APValue.h:467
virtual llvm::Value * EmitMemberPointerConversion(CodeGenFunction &CGF, const CastExpr *E, llvm::Value *Src)
Perform a derived-to-base, base-to-derived, or bitcast member pointer conversion. ...
Definition: CGCXXABI.cpp:68
This object has an indeterminate value (C++ [basic.indet]).
Definition: APValue.h:123
static QualType getNonMemoryType(CodeGenModule &CGM, QualType type)
bool isExpressibleAsConstantInitializer() const
Definition: ExprObjC.h:151
StringLiteral * getFunctionName()
Definition: Expr.h:1958
Encodes a location in the source.
const AddrLabelExpr * getAddrLabelDiffRHS() const
Definition: APValue.h:538
LangAS getAddressSpace() const
Return the address space of this type.
Definition: Type.h:6377
virtual ConstantAddress GenerateConstantString(const StringLiteral *)=0
Generate a constant string object.
Expr * getSubExpr() const
Definition: Expr.h:2076
ConstantAddress GetAddrOfConstantCFString(const StringLiteral *Literal)
Return a pointer to a constant CFString object for the given string.
CastKind getCastKind() const
Definition: Expr.h:3196
APValue & getUnionValue()
Definition: APValue.h:522
bool isUnnamedBitfield() const
Determines whether this is an unnamed bitfield.
Definition: Decl.h:2810
APFloat & getFloat()
Definition: APValue.h:394
QualType getBaseElementType(const ArrayType *VAT) const
Return the innermost element type of an array type.
Represents a static or instance method of a struct/union/class.
Definition: DeclCXX.h:1931
const ConstantArrayType * getAsConstantArrayType(QualType T) const
Definition: ASTContext.h:2466
ConstantAddress GetAddrOfConstantStringFromLiteral(const StringLiteral *S, StringRef Name=".str")
Return a pointer to a constant array for the given string literal.
StmtVisitor - This class implements a simple visitor for Stmt subclasses.
Definition: StmtVisitor.h:183
llvm::Constant * EmitNullConstantForBase(const CXXRecordDecl *Record)
Return a null constant appropriate for zero-initializing a base class with the given type...
llvm::Constant * GetAddrOfRTTIDescriptor(QualType Ty, bool ForEH=false)
Get the address of the RTTI descriptor for the given type.
const ArrayType * getAsArrayType(QualType T) const
Type Query functions.
llvm::Constant * emitAbstract(const Expr *E, QualType T)
Emit the result of the given expression as an abstract constant, asserting that it succeeded...
ConstantAddress GetWeakRefReference(const ValueDecl *VD)
Get a reference to the target of VD.
llvm::APInt APInt
Definition: Integral.h:27
void registerCurrentAddrPrivate(llvm::Constant *signal, llvm::GlobalValue *placeholder)
Register a &#39;signal&#39; value with the emitter to inform it where to resolve a placeholder.
llvm::GlobalVariable * getAddrOfConstantCompoundLiteralIfEmitted(const CompoundLiteralExpr *E)
If it&#39;s been emitted already, returns the GlobalVariable corresponding to a compound literal...
constexpr XRayInstrMask None
Definition: XRayInstr.h:37
bool operator<(DeclarationName LHS, DeclarationName RHS)
Ordering on two declaration names.
Expr * getSubExpr()
Definition: ExprObjC.h:142
ObjCBoxedExpr - used for generalized expression boxing.
Definition: ExprObjC.h:124
void Error(SourceLocation loc, StringRef error)
Emit a general error that something can&#39;t be done.
llvm::Constant * emitNullForMemory(QualType T)
Expr * getArrayFiller()
If this initializer list initializes an array with more elements than there are initializers in the l...
Definition: Expr.h:4497
bool hasFlexibleArrayMember() const
Definition: Decl.h:3802
bool hasSameUnqualifiedType(QualType T1, QualType T2) const
Determine whether the given types are equivalent after cvr-qualifiers have been removed.
Definition: ASTContext.h:2345
SourceLocation getExprLoc() const LLVM_READONLY
getExprLoc - Return the preferred location for the arrow when diagnosing a problem with a generic exp...
Definition: Expr.cpp:224
const Expr * getInitializer() const
Definition: Expr.h:3103
Represents a C11 generic selection.
Definition: Expr.h:5234
AddrLabelExpr - The GNU address of label extension, representing &&label.
Definition: Expr.h:3910
const FieldDecl * getTargetUnionField() const
Definition: Expr.h:3234
This class organizes the cross-function state that is used while generating LLVM code.
bool isTypeOperand() const
Definition: ExprCXX.h:804
Dataflow Directional Tag Classes.
[C99 6.4.2.2] - A predefined identifier such as func.
Definition: Expr.h:1903
EvalResult is a struct with detailed info about an evaluated expression.
Definition: Expr.h:586
const Expr * getInit() const
Definition: Decl.h:1229
static llvm::Constant * EmitNullConstantForBase(CodeGenModule &CGM, llvm::Type *baseType, const CXXRecordDecl *base)
Emit the null constant for a base subobject.
llvm::Constant * getPointer() const
Definition: Address.h:83
unsigned getArrayInitializedElts() const
Definition: APValue.h:486
llvm::Constant * EmitNullConstant(QualType T)
Return the result of value-initializing the given type, i.e.
A pointer to member type per C++ 8.3.3 - Pointers to members.
Definition: Type.h:2833
llvm::Module & getModule() const
specific_decl_iterator - Iterates over a subrange of declarations stored in a DeclContext, providing only those that are of type SpecificDecl (or a class derived from it).
Definition: DeclBase.h:2053
LabelDecl * getLabel() const
Definition: Expr.h:3932
llvm::Constant * tryEmitPrivateForMemory(const Expr *E, QualType T)
void EmitExplicitCastExprType(const ExplicitCastExpr *E, CodeGenFunction *CGF=nullptr)
Emit type info if type of an expression is a variably modified type.
Definition: CGExpr.cpp:1023
bool HasSideEffects
Whether the evaluated expression has side effects.
Definition: Expr.h:559
A helper class that allows the use of isa/cast/dyncast to detect TagType objects of structs/unions/cl...
Definition: Type.h:4495
StmtVisitorBase - This class implements a simple visitor for Stmt subclasses.
Definition: StmtVisitor.h:36
ObjCEncodeExpr, used for @encode in Objective-C.
Definition: ExprObjC.h:407
const llvm::APInt & getSize() const
Definition: Type.h:2958
uint64_t getCharWidth() const
Return the size of the character type, in bits.
Definition: ASTContext.h:2108
void getObjCEncodingForType(QualType T, std::string &S, const FieldDecl *Field=nullptr, QualType *NotEncodedT=nullptr) const
Emit the Objective-CC type encoding for the given type T into S.
Expr * getArg(unsigned Arg)
Return the specified argument.
Definition: ExprCXX.h:1573
llvm::StructType * getLLVMType() const
Return the "complete object" LLVM type associated with this record.
llvm::Constant * GetAddrOfFunction(GlobalDecl GD, llvm::Type *Ty=nullptr, bool ForVTable=false, bool DontDefer=false, ForDefinition_t IsForDefinition=NotForDefinition)
Return the address of the given function.
Internal linkage, which indicates that the entity can be referred to from within the translation unit...
Definition: Linkage.h:31
ConstantAddress GetAddrOfConstantCompoundLiteral(const CompoundLiteralExpr *E)
Returns a pointer to a constant global variable for the given file-scope compound literal expression...
APValue - This class implements a discriminated union of [uninitialized] [APSInt] [APFloat]...
Definition: APValue.h:115
Represents a base class of a C++ class.
Definition: DeclCXX.h:145
uint64_t getTypeSize(QualType T) const
Return the size of the specified (complete) type T, in bits.
Definition: ASTContext.h:2104
A use of a default initializer in a constructor or in aggregate initialization.
Definition: ExprCXX.h:1279
void setAddrOfConstantCompoundLiteral(const CompoundLiteralExpr *CLE, llvm::GlobalVariable *GV)
Notes that CLE&#39;s GlobalVariable is GV.
static llvm::Constant * EmitNullConstant(CodeGenModule &CGM, const RecordDecl *record, bool asCompleteObject)
CharUnits toCharUnitsFromBits(int64_t BitSize) const
Convert a size in bits to a size in characters.
int64_t toBits(CharUnits CharSize) const
Convert a size in characters to a size in bits.
ValueKind getKind() const
Definition: APValue.h:355
APFloat & getComplexFloatImag()
Definition: APValue.h:434
Represents a C++ struct/union/class.
Definition: DeclCXX.h:253
ChooseExpr - GNU builtin-in function __builtin_choose_expr.
Definition: Expr.h:4130
Qualifiers getQualifiers() const
Retrieve the set of qualifiers applied to this type.
Definition: Type.h:6283
A specialization of Address that requires the address to be an LLVM Constant.
Definition: Address.h:74
There is no such object (it&#39;s outside its lifetime).
Definition: APValue.h:121
CharUnits getNonVirtualSize() const
getNonVirtualSize - Get the non-virtual size (in chars) of an object, which is the size of the object...
Definition: RecordLayout.h:202
unsigned getVirtualBaseIndex(const CXXRecordDecl *base) const
Return the LLVM field index corresponding to the given virtual base.
__DEVICE__ int min(int __a, int __b)
StringLiteral - This represents a string literal expression, e.g.
Definition: Expr.h:1711
CallExpr - Represents a function call (C99 6.5.2.2, C++ [expr.call]).
Definition: Expr.h:2546
void finalize(llvm::GlobalVariable *global)
llvm::Constant * tryEmitAbstract(const Expr *E, QualType T)
Try to emit the result of the given expression as an abstract constant.
static ConstantAddress invalid()
Definition: Address.h:79
CGCXXABI & getCXXABI() const
bool isUnion() const
Definition: Decl.h:3407
llvm::Constant * tryEmitAbstractForMemory(const Expr *E, QualType T)
CharUnits getTypeSizeInChars(QualType T) const
Return the size of the specified (complete) type T, in characters.
FieldDecl * getInitializedFieldInUnion()
If this initializes a union, specifies which field in the union to initialize.
Definition: Expr.h:4515
llvm::Constant * GetAddrOfGlobalBlock(const BlockExpr *BE, StringRef Name)
Gets the address of a block which requires no captures.
Definition: CGBlocks.cpp:1361
QualType getType() const
Definition: Decl.h:630
unsigned getNumArgs() const
Return the number of arguments to the constructor call.
Definition: ExprCXX.h:1570
llvm::BlockAddress * GetAddrOfLabel(const LabelDecl *L)
A Microsoft C++ __uuidof expression, which gets the _GUID that corresponds to the supplied type or ex...
Definition: ExprCXX.h:1000
APSInt & getInt()
Definition: APValue.h:380
unsigned getTargetAddressSpace(QualType T) const
Definition: ASTContext.h:2557
bool isZeroSize(const ASTContext &Ctx) const
Determine if this field is a subobject of zero size, that is, either a zero-length bit-field or a fie...
Definition: Decl.cpp:4041
const CGRecordLayout & getCGRecordLayout(const RecordDecl *)
getCGRecordLayout - Return record layout info for the given record decl.
Expr * getSubExpr() const
Retrieve the temporary-generating subexpression whose value will be materialized into a glvalue...
Definition: ExprCXX.h:4436
const LangOptions & getLangOpts() const
Definition: ASTContext.h:724
Represents the canonical version of C arrays with a specified constant size.
Definition: Type.h:2935
Defines enum values for all the target-independent builtin functions.
Represents an implicitly-generated value initialization of an object of a given type.
Definition: Expr.h:5117
APFixedPoint & getFixedPoint()
Definition: APValue.h:402
CharUnits & getLValueOffset()
Definition: APValue.cpp:743
unsigned getLLVMFieldNo(const FieldDecl *FD) const
Return llvm::StructType element number that corresponds to the field FD.
unsigned getVectorLength() const
Definition: APValue.h:462