clang  9.0.0svn
CGExprScalar.cpp
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1 //===--- CGExprScalar.cpp - Emit LLVM Code for Scalar Exprs ---------------===//
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 Expr nodes with scalar LLVM types as LLVM code.
10 //
11 //===----------------------------------------------------------------------===//
12 
13 #include "CGCXXABI.h"
14 #include "CGCleanup.h"
15 #include "CGDebugInfo.h"
16 #include "CGObjCRuntime.h"
17 #include "CodeGenFunction.h"
18 #include "CodeGenModule.h"
19 #include "ConstantEmitter.h"
20 #include "TargetInfo.h"
21 #include "clang/AST/ASTContext.h"
22 #include "clang/AST/DeclObjC.h"
23 #include "clang/AST/Expr.h"
24 #include "clang/AST/RecordLayout.h"
25 #include "clang/AST/StmtVisitor.h"
27 #include "clang/Basic/FixedPoint.h"
28 #include "clang/Basic/TargetInfo.h"
29 #include "llvm/ADT/Optional.h"
30 #include "llvm/IR/CFG.h"
31 #include "llvm/IR/Constants.h"
32 #include "llvm/IR/DataLayout.h"
33 #include "llvm/IR/Function.h"
34 #include "llvm/IR/GetElementPtrTypeIterator.h"
35 #include "llvm/IR/GlobalVariable.h"
36 #include "llvm/IR/Intrinsics.h"
37 #include "llvm/IR/Module.h"
38 #include <cstdarg>
39 
40 using namespace clang;
41 using namespace CodeGen;
42 using llvm::Value;
43 
44 //===----------------------------------------------------------------------===//
45 // Scalar Expression Emitter
46 //===----------------------------------------------------------------------===//
47 
48 namespace {
49 
50 /// Determine whether the given binary operation may overflow.
51 /// Sets \p Result to the value of the operation for BO_Add, BO_Sub, BO_Mul,
52 /// and signed BO_{Div,Rem}. For these opcodes, and for unsigned BO_{Div,Rem},
53 /// the returned overflow check is precise. The returned value is 'true' for
54 /// all other opcodes, to be conservative.
55 bool mayHaveIntegerOverflow(llvm::ConstantInt *LHS, llvm::ConstantInt *RHS,
56  BinaryOperator::Opcode Opcode, bool Signed,
57  llvm::APInt &Result) {
58  // Assume overflow is possible, unless we can prove otherwise.
59  bool Overflow = true;
60  const auto &LHSAP = LHS->getValue();
61  const auto &RHSAP = RHS->getValue();
62  if (Opcode == BO_Add) {
63  if (Signed)
64  Result = LHSAP.sadd_ov(RHSAP, Overflow);
65  else
66  Result = LHSAP.uadd_ov(RHSAP, Overflow);
67  } else if (Opcode == BO_Sub) {
68  if (Signed)
69  Result = LHSAP.ssub_ov(RHSAP, Overflow);
70  else
71  Result = LHSAP.usub_ov(RHSAP, Overflow);
72  } else if (Opcode == BO_Mul) {
73  if (Signed)
74  Result = LHSAP.smul_ov(RHSAP, Overflow);
75  else
76  Result = LHSAP.umul_ov(RHSAP, Overflow);
77  } else if (Opcode == BO_Div || Opcode == BO_Rem) {
78  if (Signed && !RHS->isZero())
79  Result = LHSAP.sdiv_ov(RHSAP, Overflow);
80  else
81  return false;
82  }
83  return Overflow;
84 }
85 
86 struct BinOpInfo {
87  Value *LHS;
88  Value *RHS;
89  QualType Ty; // Computation Type.
90  BinaryOperator::Opcode Opcode; // Opcode of BinOp to perform
91  FPOptions FPFeatures;
92  const Expr *E; // Entire expr, for error unsupported. May not be binop.
93 
94  /// Check if the binop can result in integer overflow.
95  bool mayHaveIntegerOverflow() const {
96  // Without constant input, we can't rule out overflow.
97  auto *LHSCI = dyn_cast<llvm::ConstantInt>(LHS);
98  auto *RHSCI = dyn_cast<llvm::ConstantInt>(RHS);
99  if (!LHSCI || !RHSCI)
100  return true;
101 
102  llvm::APInt Result;
103  return ::mayHaveIntegerOverflow(
104  LHSCI, RHSCI, Opcode, Ty->hasSignedIntegerRepresentation(), Result);
105  }
106 
107  /// Check if the binop computes a division or a remainder.
108  bool isDivremOp() const {
109  return Opcode == BO_Div || Opcode == BO_Rem || Opcode == BO_DivAssign ||
110  Opcode == BO_RemAssign;
111  }
112 
113  /// Check if the binop can result in an integer division by zero.
114  bool mayHaveIntegerDivisionByZero() const {
115  if (isDivremOp())
116  if (auto *CI = dyn_cast<llvm::ConstantInt>(RHS))
117  return CI->isZero();
118  return true;
119  }
120 
121  /// Check if the binop can result in a float division by zero.
122  bool mayHaveFloatDivisionByZero() const {
123  if (isDivremOp())
124  if (auto *CFP = dyn_cast<llvm::ConstantFP>(RHS))
125  return CFP->isZero();
126  return true;
127  }
128 
129  /// Check if either operand is a fixed point type or integer type, with at
130  /// least one being a fixed point type. In any case, this
131  /// operation did not follow usual arithmetic conversion and both operands may
132  /// not be the same.
133  bool isFixedPointBinOp() const {
134  // We cannot simply check the result type since comparison operations return
135  // an int.
136  if (const auto *BinOp = dyn_cast<BinaryOperator>(E)) {
137  QualType LHSType = BinOp->getLHS()->getType();
138  QualType RHSType = BinOp->getRHS()->getType();
139  return LHSType->isFixedPointType() || RHSType->isFixedPointType();
140  }
141  return false;
142  }
143 };
144 
145 static bool MustVisitNullValue(const Expr *E) {
146  // If a null pointer expression's type is the C++0x nullptr_t, then
147  // it's not necessarily a simple constant and it must be evaluated
148  // for its potential side effects.
149  return E->getType()->isNullPtrType();
150 }
151 
152 /// If \p E is a widened promoted integer, get its base (unpromoted) type.
153 static llvm::Optional<QualType> getUnwidenedIntegerType(const ASTContext &Ctx,
154  const Expr *E) {
155  const Expr *Base = E->IgnoreImpCasts();
156  if (E == Base)
157  return llvm::None;
158 
159  QualType BaseTy = Base->getType();
160  if (!BaseTy->isPromotableIntegerType() ||
161  Ctx.getTypeSize(BaseTy) >= Ctx.getTypeSize(E->getType()))
162  return llvm::None;
163 
164  return BaseTy;
165 }
166 
167 /// Check if \p E is a widened promoted integer.
168 static bool IsWidenedIntegerOp(const ASTContext &Ctx, const Expr *E) {
169  return getUnwidenedIntegerType(Ctx, E).hasValue();
170 }
171 
172 /// Check if we can skip the overflow check for \p Op.
173 static bool CanElideOverflowCheck(const ASTContext &Ctx, const BinOpInfo &Op) {
174  assert((isa<UnaryOperator>(Op.E) || isa<BinaryOperator>(Op.E)) &&
175  "Expected a unary or binary operator");
176 
177  // If the binop has constant inputs and we can prove there is no overflow,
178  // we can elide the overflow check.
179  if (!Op.mayHaveIntegerOverflow())
180  return true;
181 
182  // If a unary op has a widened operand, the op cannot overflow.
183  if (const auto *UO = dyn_cast<UnaryOperator>(Op.E))
184  return !UO->canOverflow();
185 
186  // We usually don't need overflow checks for binops with widened operands.
187  // Multiplication with promoted unsigned operands is a special case.
188  const auto *BO = cast<BinaryOperator>(Op.E);
189  auto OptionalLHSTy = getUnwidenedIntegerType(Ctx, BO->getLHS());
190  if (!OptionalLHSTy)
191  return false;
192 
193  auto OptionalRHSTy = getUnwidenedIntegerType(Ctx, BO->getRHS());
194  if (!OptionalRHSTy)
195  return false;
196 
197  QualType LHSTy = *OptionalLHSTy;
198  QualType RHSTy = *OptionalRHSTy;
199 
200  // This is the simple case: binops without unsigned multiplication, and with
201  // widened operands. No overflow check is needed here.
202  if ((Op.Opcode != BO_Mul && Op.Opcode != BO_MulAssign) ||
203  !LHSTy->isUnsignedIntegerType() || !RHSTy->isUnsignedIntegerType())
204  return true;
205 
206  // For unsigned multiplication the overflow check can be elided if either one
207  // of the unpromoted types are less than half the size of the promoted type.
208  unsigned PromotedSize = Ctx.getTypeSize(Op.E->getType());
209  return (2 * Ctx.getTypeSize(LHSTy)) < PromotedSize ||
210  (2 * Ctx.getTypeSize(RHSTy)) < PromotedSize;
211 }
212 
213 /// Update the FastMathFlags of LLVM IR from the FPOptions in LangOptions.
214 static void updateFastMathFlags(llvm::FastMathFlags &FMF,
215  FPOptions FPFeatures) {
216  FMF.setAllowContract(FPFeatures.allowFPContractAcrossStatement());
217 }
218 
219 /// Propagate fast-math flags from \p Op to the instruction in \p V.
220 static Value *propagateFMFlags(Value *V, const BinOpInfo &Op) {
221  if (auto *I = dyn_cast<llvm::Instruction>(V)) {
222  llvm::FastMathFlags FMF = I->getFastMathFlags();
223  updateFastMathFlags(FMF, Op.FPFeatures);
224  I->setFastMathFlags(FMF);
225  }
226  return V;
227 }
228 
229 class ScalarExprEmitter
230  : public StmtVisitor<ScalarExprEmitter, Value*> {
231  CodeGenFunction &CGF;
232  CGBuilderTy &Builder;
233  bool IgnoreResultAssign;
234  llvm::LLVMContext &VMContext;
235 public:
236 
237  ScalarExprEmitter(CodeGenFunction &cgf, bool ira=false)
238  : CGF(cgf), Builder(CGF.Builder), IgnoreResultAssign(ira),
239  VMContext(cgf.getLLVMContext()) {
240  }
241 
242  //===--------------------------------------------------------------------===//
243  // Utilities
244  //===--------------------------------------------------------------------===//
245 
246  bool TestAndClearIgnoreResultAssign() {
247  bool I = IgnoreResultAssign;
248  IgnoreResultAssign = false;
249  return I;
250  }
251 
252  llvm::Type *ConvertType(QualType T) { return CGF.ConvertType(T); }
253  LValue EmitLValue(const Expr *E) { return CGF.EmitLValue(E); }
254  LValue EmitCheckedLValue(const Expr *E, CodeGenFunction::TypeCheckKind TCK) {
255  return CGF.EmitCheckedLValue(E, TCK);
256  }
257 
258  void EmitBinOpCheck(ArrayRef<std::pair<Value *, SanitizerMask>> Checks,
259  const BinOpInfo &Info);
260 
261  Value *EmitLoadOfLValue(LValue LV, SourceLocation Loc) {
262  return CGF.EmitLoadOfLValue(LV, Loc).getScalarVal();
263  }
264 
265  void EmitLValueAlignmentAssumption(const Expr *E, Value *V) {
266  const AlignValueAttr *AVAttr = nullptr;
267  if (const auto *DRE = dyn_cast<DeclRefExpr>(E)) {
268  const ValueDecl *VD = DRE->getDecl();
269 
270  if (VD->getType()->isReferenceType()) {
271  if (const auto *TTy =
272  dyn_cast<TypedefType>(VD->getType().getNonReferenceType()))
273  AVAttr = TTy->getDecl()->getAttr<AlignValueAttr>();
274  } else {
275  // Assumptions for function parameters are emitted at the start of the
276  // function, so there is no need to repeat that here,
277  // unless the alignment-assumption sanitizer is enabled,
278  // then we prefer the assumption over alignment attribute
279  // on IR function param.
280  if (isa<ParmVarDecl>(VD) && !CGF.SanOpts.has(SanitizerKind::Alignment))
281  return;
282 
283  AVAttr = VD->getAttr<AlignValueAttr>();
284  }
285  }
286 
287  if (!AVAttr)
288  if (const auto *TTy =
289  dyn_cast<TypedefType>(E->getType()))
290  AVAttr = TTy->getDecl()->getAttr<AlignValueAttr>();
291 
292  if (!AVAttr)
293  return;
294 
295  Value *AlignmentValue = CGF.EmitScalarExpr(AVAttr->getAlignment());
296  llvm::ConstantInt *AlignmentCI = cast<llvm::ConstantInt>(AlignmentValue);
297  CGF.EmitAlignmentAssumption(V, E, AVAttr->getLocation(),
298  AlignmentCI->getZExtValue());
299  }
300 
301  /// EmitLoadOfLValue - Given an expression with complex type that represents a
302  /// value l-value, this method emits the address of the l-value, then loads
303  /// and returns the result.
304  Value *EmitLoadOfLValue(const Expr *E) {
305  Value *V = EmitLoadOfLValue(EmitCheckedLValue(E, CodeGenFunction::TCK_Load),
306  E->getExprLoc());
307 
308  EmitLValueAlignmentAssumption(E, V);
309  return V;
310  }
311 
312  /// EmitConversionToBool - Convert the specified expression value to a
313  /// boolean (i1) truth value. This is equivalent to "Val != 0".
314  Value *EmitConversionToBool(Value *Src, QualType DstTy);
315 
316  /// Emit a check that a conversion to or from a floating-point type does not
317  /// overflow.
318  void EmitFloatConversionCheck(Value *OrigSrc, QualType OrigSrcType,
319  Value *Src, QualType SrcType, QualType DstType,
320  llvm::Type *DstTy, SourceLocation Loc);
321 
322  /// Known implicit conversion check kinds.
323  /// Keep in sync with the enum of the same name in ubsan_handlers.h
324  enum ImplicitConversionCheckKind : unsigned char {
325  ICCK_IntegerTruncation = 0, // Legacy, was only used by clang 7.
326  ICCK_UnsignedIntegerTruncation = 1,
327  ICCK_SignedIntegerTruncation = 2,
328  ICCK_IntegerSignChange = 3,
329  ICCK_SignedIntegerTruncationOrSignChange = 4,
330  };
331 
332  /// Emit a check that an [implicit] truncation of an integer does not
333  /// discard any bits. It is not UB, so we use the value after truncation.
334  void EmitIntegerTruncationCheck(Value *Src, QualType SrcType, Value *Dst,
335  QualType DstType, SourceLocation Loc);
336 
337  /// Emit a check that an [implicit] conversion of an integer does not change
338  /// the sign of the value. It is not UB, so we use the value after conversion.
339  /// NOTE: Src and Dst may be the exact same value! (point to the same thing)
340  void EmitIntegerSignChangeCheck(Value *Src, QualType SrcType, Value *Dst,
341  QualType DstType, SourceLocation Loc);
342 
343  /// Emit a conversion from the specified type to the specified destination
344  /// type, both of which are LLVM scalar types.
345  struct ScalarConversionOpts {
346  bool TreatBooleanAsSigned;
347  bool EmitImplicitIntegerTruncationChecks;
348  bool EmitImplicitIntegerSignChangeChecks;
349 
350  ScalarConversionOpts()
351  : TreatBooleanAsSigned(false),
352  EmitImplicitIntegerTruncationChecks(false),
353  EmitImplicitIntegerSignChangeChecks(false) {}
354 
355  ScalarConversionOpts(clang::SanitizerSet SanOpts)
356  : TreatBooleanAsSigned(false),
357  EmitImplicitIntegerTruncationChecks(
358  SanOpts.hasOneOf(SanitizerKind::ImplicitIntegerTruncation)),
359  EmitImplicitIntegerSignChangeChecks(
360  SanOpts.has(SanitizerKind::ImplicitIntegerSignChange)) {}
361  };
362  Value *
363  EmitScalarConversion(Value *Src, QualType SrcTy, QualType DstTy,
364  SourceLocation Loc,
365  ScalarConversionOpts Opts = ScalarConversionOpts());
366 
367  /// Convert between either a fixed point and other fixed point or fixed point
368  /// and an integer.
369  Value *EmitFixedPointConversion(Value *Src, QualType SrcTy, QualType DstTy,
370  SourceLocation Loc);
371  Value *EmitFixedPointConversion(Value *Src, FixedPointSemantics &SrcFixedSema,
372  FixedPointSemantics &DstFixedSema,
373  SourceLocation Loc,
374  bool DstIsInteger = false);
375 
376  /// Emit a conversion from the specified complex type to the specified
377  /// destination type, where the destination type is an LLVM scalar type.
378  Value *EmitComplexToScalarConversion(CodeGenFunction::ComplexPairTy Src,
379  QualType SrcTy, QualType DstTy,
380  SourceLocation Loc);
381 
382  /// EmitNullValue - Emit a value that corresponds to null for the given type.
383  Value *EmitNullValue(QualType Ty);
384 
385  /// EmitFloatToBoolConversion - Perform an FP to boolean conversion.
386  Value *EmitFloatToBoolConversion(Value *V) {
387  // Compare against 0.0 for fp scalars.
388  llvm::Value *Zero = llvm::Constant::getNullValue(V->getType());
389  return Builder.CreateFCmpUNE(V, Zero, "tobool");
390  }
391 
392  /// EmitPointerToBoolConversion - Perform a pointer to boolean conversion.
393  Value *EmitPointerToBoolConversion(Value *V, QualType QT) {
394  Value *Zero = CGF.CGM.getNullPointer(cast<llvm::PointerType>(V->getType()), QT);
395 
396  return Builder.CreateICmpNE(V, Zero, "tobool");
397  }
398 
399  Value *EmitIntToBoolConversion(Value *V) {
400  // Because of the type rules of C, we often end up computing a
401  // logical value, then zero extending it to int, then wanting it
402  // as a logical value again. Optimize this common case.
403  if (llvm::ZExtInst *ZI = dyn_cast<llvm::ZExtInst>(V)) {
404  if (ZI->getOperand(0)->getType() == Builder.getInt1Ty()) {
405  Value *Result = ZI->getOperand(0);
406  // If there aren't any more uses, zap the instruction to save space.
407  // Note that there can be more uses, for example if this
408  // is the result of an assignment.
409  if (ZI->use_empty())
410  ZI->eraseFromParent();
411  return Result;
412  }
413  }
414 
415  return Builder.CreateIsNotNull(V, "tobool");
416  }
417 
418  //===--------------------------------------------------------------------===//
419  // Visitor Methods
420  //===--------------------------------------------------------------------===//
421 
422  Value *Visit(Expr *E) {
423  ApplyDebugLocation DL(CGF, E);
425  }
426 
427  Value *VisitStmt(Stmt *S) {
428  S->dump(CGF.getContext().getSourceManager());
429  llvm_unreachable("Stmt can't have complex result type!");
430  }
431  Value *VisitExpr(Expr *S);
432 
433  Value *VisitConstantExpr(ConstantExpr *E) {
434  return Visit(E->getSubExpr());
435  }
436  Value *VisitParenExpr(ParenExpr *PE) {
437  return Visit(PE->getSubExpr());
438  }
439  Value *VisitSubstNonTypeTemplateParmExpr(SubstNonTypeTemplateParmExpr *E) {
440  return Visit(E->getReplacement());
441  }
442  Value *VisitGenericSelectionExpr(GenericSelectionExpr *GE) {
443  return Visit(GE->getResultExpr());
444  }
445  Value *VisitCoawaitExpr(CoawaitExpr *S) {
446  return CGF.EmitCoawaitExpr(*S).getScalarVal();
447  }
448  Value *VisitCoyieldExpr(CoyieldExpr *S) {
449  return CGF.EmitCoyieldExpr(*S).getScalarVal();
450  }
451  Value *VisitUnaryCoawait(const UnaryOperator *E) {
452  return Visit(E->getSubExpr());
453  }
454 
455  // Leaves.
456  Value *VisitIntegerLiteral(const IntegerLiteral *E) {
457  return Builder.getInt(E->getValue());
458  }
459  Value *VisitFixedPointLiteral(const FixedPointLiteral *E) {
460  return Builder.getInt(E->getValue());
461  }
462  Value *VisitFloatingLiteral(const FloatingLiteral *E) {
463  return llvm::ConstantFP::get(VMContext, E->getValue());
464  }
465  Value *VisitCharacterLiteral(const CharacterLiteral *E) {
466  return llvm::ConstantInt::get(ConvertType(E->getType()), E->getValue());
467  }
468  Value *VisitObjCBoolLiteralExpr(const ObjCBoolLiteralExpr *E) {
469  return llvm::ConstantInt::get(ConvertType(E->getType()), E->getValue());
470  }
471  Value *VisitCXXBoolLiteralExpr(const CXXBoolLiteralExpr *E) {
472  return llvm::ConstantInt::get(ConvertType(E->getType()), E->getValue());
473  }
474  Value *VisitCXXScalarValueInitExpr(const CXXScalarValueInitExpr *E) {
475  return EmitNullValue(E->getType());
476  }
477  Value *VisitGNUNullExpr(const GNUNullExpr *E) {
478  return EmitNullValue(E->getType());
479  }
480  Value *VisitOffsetOfExpr(OffsetOfExpr *E);
481  Value *VisitUnaryExprOrTypeTraitExpr(const UnaryExprOrTypeTraitExpr *E);
482  Value *VisitAddrLabelExpr(const AddrLabelExpr *E) {
483  llvm::Value *V = CGF.GetAddrOfLabel(E->getLabel());
484  return Builder.CreateBitCast(V, ConvertType(E->getType()));
485  }
486 
487  Value *VisitSizeOfPackExpr(SizeOfPackExpr *E) {
488  return llvm::ConstantInt::get(ConvertType(E->getType()),E->getPackLength());
489  }
490 
491  Value *VisitPseudoObjectExpr(PseudoObjectExpr *E) {
492  return CGF.EmitPseudoObjectRValue(E).getScalarVal();
493  }
494 
495  Value *VisitOpaqueValueExpr(OpaqueValueExpr *E) {
496  if (E->isGLValue())
497  return EmitLoadOfLValue(CGF.getOrCreateOpaqueLValueMapping(E),
498  E->getExprLoc());
499 
500  // Otherwise, assume the mapping is the scalar directly.
502  }
503 
504  // l-values.
505  Value *VisitDeclRefExpr(DeclRefExpr *E) {
507  return CGF.emitScalarConstant(Constant, E);
508  return EmitLoadOfLValue(E);
509  }
510 
511  Value *VisitObjCSelectorExpr(ObjCSelectorExpr *E) {
512  return CGF.EmitObjCSelectorExpr(E);
513  }
514  Value *VisitObjCProtocolExpr(ObjCProtocolExpr *E) {
515  return CGF.EmitObjCProtocolExpr(E);
516  }
517  Value *VisitObjCIvarRefExpr(ObjCIvarRefExpr *E) {
518  return EmitLoadOfLValue(E);
519  }
520  Value *VisitObjCMessageExpr(ObjCMessageExpr *E) {
521  if (E->getMethodDecl() &&
523  return EmitLoadOfLValue(E);
524  return CGF.EmitObjCMessageExpr(E).getScalarVal();
525  }
526 
527  Value *VisitObjCIsaExpr(ObjCIsaExpr *E) {
528  LValue LV = CGF.EmitObjCIsaExpr(E);
529  Value *V = CGF.EmitLoadOfLValue(LV, E->getExprLoc()).getScalarVal();
530  return V;
531  }
532 
533  Value *VisitObjCAvailabilityCheckExpr(ObjCAvailabilityCheckExpr *E) {
534  VersionTuple Version = E->getVersion();
535 
536  // If we're checking for a platform older than our minimum deployment
537  // target, we can fold the check away.
538  if (Version <= CGF.CGM.getTarget().getPlatformMinVersion())
539  return llvm::ConstantInt::get(Builder.getInt1Ty(), 1);
540 
541  Optional<unsigned> Min = Version.getMinor(), SMin = Version.getSubminor();
542  llvm::Value *Args[] = {
543  llvm::ConstantInt::get(CGF.CGM.Int32Ty, Version.getMajor()),
544  llvm::ConstantInt::get(CGF.CGM.Int32Ty, Min ? *Min : 0),
545  llvm::ConstantInt::get(CGF.CGM.Int32Ty, SMin ? *SMin : 0),
546  };
547 
548  return CGF.EmitBuiltinAvailable(Args);
549  }
550 
551  Value *VisitArraySubscriptExpr(ArraySubscriptExpr *E);
552  Value *VisitShuffleVectorExpr(ShuffleVectorExpr *E);
553  Value *VisitConvertVectorExpr(ConvertVectorExpr *E);
554  Value *VisitMemberExpr(MemberExpr *E);
555  Value *VisitExtVectorElementExpr(Expr *E) { return EmitLoadOfLValue(E); }
556  Value *VisitCompoundLiteralExpr(CompoundLiteralExpr *E) {
557  return EmitLoadOfLValue(E);
558  }
559 
560  Value *VisitInitListExpr(InitListExpr *E);
561 
562  Value *VisitArrayInitIndexExpr(ArrayInitIndexExpr *E) {
563  assert(CGF.getArrayInitIndex() &&
564  "ArrayInitIndexExpr not inside an ArrayInitLoopExpr?");
565  return CGF.getArrayInitIndex();
566  }
567 
568  Value *VisitImplicitValueInitExpr(const ImplicitValueInitExpr *E) {
569  return EmitNullValue(E->getType());
570  }
571  Value *VisitExplicitCastExpr(ExplicitCastExpr *E) {
572  CGF.CGM.EmitExplicitCastExprType(E, &CGF);
573  return VisitCastExpr(E);
574  }
575  Value *VisitCastExpr(CastExpr *E);
576 
577  Value *VisitCallExpr(const CallExpr *E) {
578  if (E->getCallReturnType(CGF.getContext())->isReferenceType())
579  return EmitLoadOfLValue(E);
580 
581  Value *V = CGF.EmitCallExpr(E).getScalarVal();
582 
583  EmitLValueAlignmentAssumption(E, V);
584  return V;
585  }
586 
587  Value *VisitStmtExpr(const StmtExpr *E);
588 
589  // Unary Operators.
590  Value *VisitUnaryPostDec(const UnaryOperator *E) {
591  LValue LV = EmitLValue(E->getSubExpr());
592  return EmitScalarPrePostIncDec(E, LV, false, false);
593  }
594  Value *VisitUnaryPostInc(const UnaryOperator *E) {
595  LValue LV = EmitLValue(E->getSubExpr());
596  return EmitScalarPrePostIncDec(E, LV, true, false);
597  }
598  Value *VisitUnaryPreDec(const UnaryOperator *E) {
599  LValue LV = EmitLValue(E->getSubExpr());
600  return EmitScalarPrePostIncDec(E, LV, false, true);
601  }
602  Value *VisitUnaryPreInc(const UnaryOperator *E) {
603  LValue LV = EmitLValue(E->getSubExpr());
604  return EmitScalarPrePostIncDec(E, LV, true, true);
605  }
606 
607  llvm::Value *EmitIncDecConsiderOverflowBehavior(const UnaryOperator *E,
608  llvm::Value *InVal,
609  bool IsInc);
610 
611  llvm::Value *EmitScalarPrePostIncDec(const UnaryOperator *E, LValue LV,
612  bool isInc, bool isPre);
613 
614 
615  Value *VisitUnaryAddrOf(const UnaryOperator *E) {
616  if (isa<MemberPointerType>(E->getType())) // never sugared
617  return CGF.CGM.getMemberPointerConstant(E);
618 
619  return EmitLValue(E->getSubExpr()).getPointer();
620  }
621  Value *VisitUnaryDeref(const UnaryOperator *E) {
622  if (E->getType()->isVoidType())
623  return Visit(E->getSubExpr()); // the actual value should be unused
624  return EmitLoadOfLValue(E);
625  }
626  Value *VisitUnaryPlus(const UnaryOperator *E) {
627  // This differs from gcc, though, most likely due to a bug in gcc.
628  TestAndClearIgnoreResultAssign();
629  return Visit(E->getSubExpr());
630  }
631  Value *VisitUnaryMinus (const UnaryOperator *E);
632  Value *VisitUnaryNot (const UnaryOperator *E);
633  Value *VisitUnaryLNot (const UnaryOperator *E);
634  Value *VisitUnaryReal (const UnaryOperator *E);
635  Value *VisitUnaryImag (const UnaryOperator *E);
636  Value *VisitUnaryExtension(const UnaryOperator *E) {
637  return Visit(E->getSubExpr());
638  }
639 
640  // C++
641  Value *VisitMaterializeTemporaryExpr(const MaterializeTemporaryExpr *E) {
642  return EmitLoadOfLValue(E);
643  }
644  Value *VisitSourceLocExpr(SourceLocExpr *SLE) {
645  auto &Ctx = CGF.getContext();
646  APValue Evaluated =
648  return ConstantEmitter(CGF.CGM, &CGF)
649  .emitAbstract(SLE->getLocation(), Evaluated, SLE->getType());
650  }
651 
652  Value *VisitCXXDefaultArgExpr(CXXDefaultArgExpr *DAE) {
654  return Visit(DAE->getExpr());
655  }
656  Value *VisitCXXDefaultInitExpr(CXXDefaultInitExpr *DIE) {
658  return Visit(DIE->getExpr());
659  }
660  Value *VisitCXXThisExpr(CXXThisExpr *TE) {
661  return CGF.LoadCXXThis();
662  }
663 
664  Value *VisitExprWithCleanups(ExprWithCleanups *E);
665  Value *VisitCXXNewExpr(const CXXNewExpr *E) {
666  return CGF.EmitCXXNewExpr(E);
667  }
668  Value *VisitCXXDeleteExpr(const CXXDeleteExpr *E) {
669  CGF.EmitCXXDeleteExpr(E);
670  return nullptr;
671  }
672 
673  Value *VisitTypeTraitExpr(const TypeTraitExpr *E) {
674  return llvm::ConstantInt::get(ConvertType(E->getType()), E->getValue());
675  }
676 
677  Value *VisitArrayTypeTraitExpr(const ArrayTypeTraitExpr *E) {
678  return llvm::ConstantInt::get(Builder.getInt32Ty(), E->getValue());
679  }
680 
681  Value *VisitExpressionTraitExpr(const ExpressionTraitExpr *E) {
682  return llvm::ConstantInt::get(Builder.getInt1Ty(), E->getValue());
683  }
684 
685  Value *VisitCXXPseudoDestructorExpr(const CXXPseudoDestructorExpr *E) {
686  // C++ [expr.pseudo]p1:
687  // The result shall only be used as the operand for the function call
688  // operator (), and the result of such a call has type void. The only
689  // effect is the evaluation of the postfix-expression before the dot or
690  // arrow.
691  CGF.EmitScalarExpr(E->getBase());
692  return nullptr;
693  }
694 
695  Value *VisitCXXNullPtrLiteralExpr(const CXXNullPtrLiteralExpr *E) {
696  return EmitNullValue(E->getType());
697  }
698 
699  Value *VisitCXXThrowExpr(const CXXThrowExpr *E) {
700  CGF.EmitCXXThrowExpr(E);
701  return nullptr;
702  }
703 
704  Value *VisitCXXNoexceptExpr(const CXXNoexceptExpr *E) {
705  return Builder.getInt1(E->getValue());
706  }
707 
708  // Binary Operators.
709  Value *EmitMul(const BinOpInfo &Ops) {
710  if (Ops.Ty->isSignedIntegerOrEnumerationType()) {
711  switch (CGF.getLangOpts().getSignedOverflowBehavior()) {
713  return Builder.CreateMul(Ops.LHS, Ops.RHS, "mul");
715  if (!CGF.SanOpts.has(SanitizerKind::SignedIntegerOverflow))
716  return Builder.CreateNSWMul(Ops.LHS, Ops.RHS, "mul");
717  LLVM_FALLTHROUGH;
719  if (CanElideOverflowCheck(CGF.getContext(), Ops))
720  return Builder.CreateNSWMul(Ops.LHS, Ops.RHS, "mul");
721  return EmitOverflowCheckedBinOp(Ops);
722  }
723  }
724 
725  if (Ops.Ty->isUnsignedIntegerType() &&
726  CGF.SanOpts.has(SanitizerKind::UnsignedIntegerOverflow) &&
727  !CanElideOverflowCheck(CGF.getContext(), Ops))
728  return EmitOverflowCheckedBinOp(Ops);
729 
730  if (Ops.LHS->getType()->isFPOrFPVectorTy()) {
731  Value *V = Builder.CreateFMul(Ops.LHS, Ops.RHS, "mul");
732  return propagateFMFlags(V, Ops);
733  }
734  return Builder.CreateMul(Ops.LHS, Ops.RHS, "mul");
735  }
736  /// Create a binary op that checks for overflow.
737  /// Currently only supports +, - and *.
738  Value *EmitOverflowCheckedBinOp(const BinOpInfo &Ops);
739 
740  // Check for undefined division and modulus behaviors.
741  void EmitUndefinedBehaviorIntegerDivAndRemCheck(const BinOpInfo &Ops,
742  llvm::Value *Zero,bool isDiv);
743  // Common helper for getting how wide LHS of shift is.
744  static Value *GetWidthMinusOneValue(Value* LHS,Value* RHS);
745  Value *EmitDiv(const BinOpInfo &Ops);
746  Value *EmitRem(const BinOpInfo &Ops);
747  Value *EmitAdd(const BinOpInfo &Ops);
748  Value *EmitSub(const BinOpInfo &Ops);
749  Value *EmitShl(const BinOpInfo &Ops);
750  Value *EmitShr(const BinOpInfo &Ops);
751  Value *EmitAnd(const BinOpInfo &Ops) {
752  return Builder.CreateAnd(Ops.LHS, Ops.RHS, "and");
753  }
754  Value *EmitXor(const BinOpInfo &Ops) {
755  return Builder.CreateXor(Ops.LHS, Ops.RHS, "xor");
756  }
757  Value *EmitOr (const BinOpInfo &Ops) {
758  return Builder.CreateOr(Ops.LHS, Ops.RHS, "or");
759  }
760 
761  // Helper functions for fixed point binary operations.
762  Value *EmitFixedPointBinOp(const BinOpInfo &Ops);
763 
764  BinOpInfo EmitBinOps(const BinaryOperator *E);
765  LValue EmitCompoundAssignLValue(const CompoundAssignOperator *E,
766  Value *(ScalarExprEmitter::*F)(const BinOpInfo &),
767  Value *&Result);
768 
769  Value *EmitCompoundAssign(const CompoundAssignOperator *E,
770  Value *(ScalarExprEmitter::*F)(const BinOpInfo &));
771 
772  // Binary operators and binary compound assignment operators.
773 #define HANDLEBINOP(OP) \
774  Value *VisitBin ## OP(const BinaryOperator *E) { \
775  return Emit ## OP(EmitBinOps(E)); \
776  } \
777  Value *VisitBin ## OP ## Assign(const CompoundAssignOperator *E) { \
778  return EmitCompoundAssign(E, &ScalarExprEmitter::Emit ## OP); \
779  }
780  HANDLEBINOP(Mul)
781  HANDLEBINOP(Div)
782  HANDLEBINOP(Rem)
783  HANDLEBINOP(Add)
784  HANDLEBINOP(Sub)
785  HANDLEBINOP(Shl)
786  HANDLEBINOP(Shr)
788  HANDLEBINOP(Xor)
789  HANDLEBINOP(Or)
790 #undef HANDLEBINOP
791 
792  // Comparisons.
793  Value *EmitCompare(const BinaryOperator *E, llvm::CmpInst::Predicate UICmpOpc,
794  llvm::CmpInst::Predicate SICmpOpc,
795  llvm::CmpInst::Predicate FCmpOpc);
796 #define VISITCOMP(CODE, UI, SI, FP) \
797  Value *VisitBin##CODE(const BinaryOperator *E) { \
798  return EmitCompare(E, llvm::ICmpInst::UI, llvm::ICmpInst::SI, \
799  llvm::FCmpInst::FP); }
800  VISITCOMP(LT, ICMP_ULT, ICMP_SLT, FCMP_OLT)
801  VISITCOMP(GT, ICMP_UGT, ICMP_SGT, FCMP_OGT)
802  VISITCOMP(LE, ICMP_ULE, ICMP_SLE, FCMP_OLE)
803  VISITCOMP(GE, ICMP_UGE, ICMP_SGE, FCMP_OGE)
804  VISITCOMP(EQ, ICMP_EQ , ICMP_EQ , FCMP_OEQ)
805  VISITCOMP(NE, ICMP_NE , ICMP_NE , FCMP_UNE)
806 #undef VISITCOMP
807 
808  Value *VisitBinAssign (const BinaryOperator *E);
809 
810  Value *VisitBinLAnd (const BinaryOperator *E);
811  Value *VisitBinLOr (const BinaryOperator *E);
812  Value *VisitBinComma (const BinaryOperator *E);
813 
814  Value *VisitBinPtrMemD(const Expr *E) { return EmitLoadOfLValue(E); }
815  Value *VisitBinPtrMemI(const Expr *E) { return EmitLoadOfLValue(E); }
816 
817  // Other Operators.
818  Value *VisitBlockExpr(const BlockExpr *BE);
819  Value *VisitAbstractConditionalOperator(const AbstractConditionalOperator *);
820  Value *VisitChooseExpr(ChooseExpr *CE);
821  Value *VisitVAArgExpr(VAArgExpr *VE);
822  Value *VisitObjCStringLiteral(const ObjCStringLiteral *E) {
823  return CGF.EmitObjCStringLiteral(E);
824  }
825  Value *VisitObjCBoxedExpr(ObjCBoxedExpr *E) {
826  return CGF.EmitObjCBoxedExpr(E);
827  }
828  Value *VisitObjCArrayLiteral(ObjCArrayLiteral *E) {
829  return CGF.EmitObjCArrayLiteral(E);
830  }
831  Value *VisitObjCDictionaryLiteral(ObjCDictionaryLiteral *E) {
832  return CGF.EmitObjCDictionaryLiteral(E);
833  }
834  Value *VisitAsTypeExpr(AsTypeExpr *CE);
835  Value *VisitAtomicExpr(AtomicExpr *AE);
836 };
837 } // end anonymous namespace.
838 
839 //===----------------------------------------------------------------------===//
840 // Utilities
841 //===----------------------------------------------------------------------===//
842 
843 /// EmitConversionToBool - Convert the specified expression value to a
844 /// boolean (i1) truth value. This is equivalent to "Val != 0".
845 Value *ScalarExprEmitter::EmitConversionToBool(Value *Src, QualType SrcType) {
846  assert(SrcType.isCanonical() && "EmitScalarConversion strips typedefs");
847 
848  if (SrcType->isRealFloatingType())
849  return EmitFloatToBoolConversion(Src);
850 
851  if (const MemberPointerType *MPT = dyn_cast<MemberPointerType>(SrcType))
852  return CGF.CGM.getCXXABI().EmitMemberPointerIsNotNull(CGF, Src, MPT);
853 
854  assert((SrcType->isIntegerType() || isa<llvm::PointerType>(Src->getType())) &&
855  "Unknown scalar type to convert");
856 
857  if (isa<llvm::IntegerType>(Src->getType()))
858  return EmitIntToBoolConversion(Src);
859 
860  assert(isa<llvm::PointerType>(Src->getType()));
861  return EmitPointerToBoolConversion(Src, SrcType);
862 }
863 
864 void ScalarExprEmitter::EmitFloatConversionCheck(
865  Value *OrigSrc, QualType OrigSrcType, Value *Src, QualType SrcType,
866  QualType DstType, llvm::Type *DstTy, SourceLocation Loc) {
867  CodeGenFunction::SanitizerScope SanScope(&CGF);
868  using llvm::APFloat;
869  using llvm::APSInt;
870 
871  llvm::Type *SrcTy = Src->getType();
872 
873  llvm::Value *Check = nullptr;
874  if (llvm::IntegerType *IntTy = dyn_cast<llvm::IntegerType>(SrcTy)) {
875  // Integer to floating-point. This can fail for unsigned short -> __half
876  // or unsigned __int128 -> float.
877  assert(DstType->isFloatingType());
878  bool SrcIsUnsigned = OrigSrcType->isUnsignedIntegerOrEnumerationType();
879 
880  APFloat LargestFloat =
881  APFloat::getLargest(CGF.getContext().getFloatTypeSemantics(DstType));
882  APSInt LargestInt(IntTy->getBitWidth(), SrcIsUnsigned);
883 
884  bool IsExact;
885  if (LargestFloat.convertToInteger(LargestInt, APFloat::rmTowardZero,
886  &IsExact) != APFloat::opOK)
887  // The range of representable values of this floating point type includes
888  // all values of this integer type. Don't need an overflow check.
889  return;
890 
891  llvm::Value *Max = llvm::ConstantInt::get(VMContext, LargestInt);
892  if (SrcIsUnsigned)
893  Check = Builder.CreateICmpULE(Src, Max);
894  else {
895  llvm::Value *Min = llvm::ConstantInt::get(VMContext, -LargestInt);
896  llvm::Value *GE = Builder.CreateICmpSGE(Src, Min);
897  llvm::Value *LE = Builder.CreateICmpSLE(Src, Max);
898  Check = Builder.CreateAnd(GE, LE);
899  }
900  } else {
901  const llvm::fltSemantics &SrcSema =
902  CGF.getContext().getFloatTypeSemantics(OrigSrcType);
903  if (isa<llvm::IntegerType>(DstTy)) {
904  // Floating-point to integer. This has undefined behavior if the source is
905  // +-Inf, NaN, or doesn't fit into the destination type (after truncation
906  // to an integer).
907  unsigned Width = CGF.getContext().getIntWidth(DstType);
908  bool Unsigned = DstType->isUnsignedIntegerOrEnumerationType();
909 
910  APSInt Min = APSInt::getMinValue(Width, Unsigned);
911  APFloat MinSrc(SrcSema, APFloat::uninitialized);
912  if (MinSrc.convertFromAPInt(Min, !Unsigned, APFloat::rmTowardZero) &
913  APFloat::opOverflow)
914  // Don't need an overflow check for lower bound. Just check for
915  // -Inf/NaN.
916  MinSrc = APFloat::getInf(SrcSema, true);
917  else
918  // Find the largest value which is too small to represent (before
919  // truncation toward zero).
920  MinSrc.subtract(APFloat(SrcSema, 1), APFloat::rmTowardNegative);
921 
922  APSInt Max = APSInt::getMaxValue(Width, Unsigned);
923  APFloat MaxSrc(SrcSema, APFloat::uninitialized);
924  if (MaxSrc.convertFromAPInt(Max, !Unsigned, APFloat::rmTowardZero) &
925  APFloat::opOverflow)
926  // Don't need an overflow check for upper bound. Just check for
927  // +Inf/NaN.
928  MaxSrc = APFloat::getInf(SrcSema, false);
929  else
930  // Find the smallest value which is too large to represent (before
931  // truncation toward zero).
932  MaxSrc.add(APFloat(SrcSema, 1), APFloat::rmTowardPositive);
933 
934  // If we're converting from __half, convert the range to float to match
935  // the type of src.
936  if (OrigSrcType->isHalfType()) {
937  const llvm::fltSemantics &Sema =
938  CGF.getContext().getFloatTypeSemantics(SrcType);
939  bool IsInexact;
940  MinSrc.convert(Sema, APFloat::rmTowardZero, &IsInexact);
941  MaxSrc.convert(Sema, APFloat::rmTowardZero, &IsInexact);
942  }
943 
944  llvm::Value *GE =
945  Builder.CreateFCmpOGT(Src, llvm::ConstantFP::get(VMContext, MinSrc));
946  llvm::Value *LE =
947  Builder.CreateFCmpOLT(Src, llvm::ConstantFP::get(VMContext, MaxSrc));
948  Check = Builder.CreateAnd(GE, LE);
949  } else {
950  // FIXME: Maybe split this sanitizer out from float-cast-overflow.
951  //
952  // Floating-point to floating-point. This has undefined behavior if the
953  // source is not in the range of representable values of the destination
954  // type. The C and C++ standards are spectacularly unclear here. We
955  // diagnose finite out-of-range conversions, but allow infinities and NaNs
956  // to convert to the corresponding value in the smaller type.
957  //
958  // C11 Annex F gives all such conversions defined behavior for IEC 60559
959  // conforming implementations. Unfortunately, LLVM's fptrunc instruction
960  // does not.
961 
962  // Converting from a lower rank to a higher rank can never have
963  // undefined behavior, since higher-rank types must have a superset
964  // of values of lower-rank types.
965  if (CGF.getContext().getFloatingTypeOrder(OrigSrcType, DstType) != 1)
966  return;
967 
968  assert(!OrigSrcType->isHalfType() &&
969  "should not check conversion from __half, it has the lowest rank");
970 
971  const llvm::fltSemantics &DstSema =
972  CGF.getContext().getFloatTypeSemantics(DstType);
973  APFloat MinBad = APFloat::getLargest(DstSema, false);
974  APFloat MaxBad = APFloat::getInf(DstSema, false);
975 
976  bool IsInexact;
977  MinBad.convert(SrcSema, APFloat::rmTowardZero, &IsInexact);
978  MaxBad.convert(SrcSema, APFloat::rmTowardZero, &IsInexact);
979 
980  Value *AbsSrc = CGF.EmitNounwindRuntimeCall(
981  CGF.CGM.getIntrinsic(llvm::Intrinsic::fabs, Src->getType()), Src);
982  llvm::Value *GE =
983  Builder.CreateFCmpOGT(AbsSrc, llvm::ConstantFP::get(VMContext, MinBad));
984  llvm::Value *LE =
985  Builder.CreateFCmpOLT(AbsSrc, llvm::ConstantFP::get(VMContext, MaxBad));
986  Check = Builder.CreateNot(Builder.CreateAnd(GE, LE));
987  }
988  }
989 
990  llvm::Constant *StaticArgs[] = {CGF.EmitCheckSourceLocation(Loc),
991  CGF.EmitCheckTypeDescriptor(OrigSrcType),
992  CGF.EmitCheckTypeDescriptor(DstType)};
993  CGF.EmitCheck(std::make_pair(Check, SanitizerKind::FloatCastOverflow),
994  SanitizerHandler::FloatCastOverflow, StaticArgs, OrigSrc);
995 }
996 
997 // Should be called within CodeGenFunction::SanitizerScope RAII scope.
998 // Returns 'i1 false' when the truncation Src -> Dst was lossy.
999 static std::pair<ScalarExprEmitter::ImplicitConversionCheckKind,
1000  std::pair<llvm::Value *, SanitizerMask>>
1002  QualType DstType, CGBuilderTy &Builder) {
1003  llvm::Type *SrcTy = Src->getType();
1004  llvm::Type *DstTy = Dst->getType();
1005  (void)DstTy; // Only used in assert()
1006 
1007  // This should be truncation of integral types.
1008  assert(Src != Dst);
1009  assert(SrcTy->getScalarSizeInBits() > Dst->getType()->getScalarSizeInBits());
1010  assert(isa<llvm::IntegerType>(SrcTy) && isa<llvm::IntegerType>(DstTy) &&
1011  "non-integer llvm type");
1012 
1013  bool SrcSigned = SrcType->isSignedIntegerOrEnumerationType();
1014  bool DstSigned = DstType->isSignedIntegerOrEnumerationType();
1015 
1016  // If both (src and dst) types are unsigned, then it's an unsigned truncation.
1017  // Else, it is a signed truncation.
1018  ScalarExprEmitter::ImplicitConversionCheckKind Kind;
1019  SanitizerMask Mask;
1020  if (!SrcSigned && !DstSigned) {
1021  Kind = ScalarExprEmitter::ICCK_UnsignedIntegerTruncation;
1022  Mask = SanitizerKind::ImplicitUnsignedIntegerTruncation;
1023  } else {
1024  Kind = ScalarExprEmitter::ICCK_SignedIntegerTruncation;
1025  Mask = SanitizerKind::ImplicitSignedIntegerTruncation;
1026  }
1027 
1028  llvm::Value *Check = nullptr;
1029  // 1. Extend the truncated value back to the same width as the Src.
1030  Check = Builder.CreateIntCast(Dst, SrcTy, DstSigned, "anyext");
1031  // 2. Equality-compare with the original source value
1032  Check = Builder.CreateICmpEQ(Check, Src, "truncheck");
1033  // If the comparison result is 'i1 false', then the truncation was lossy.
1034  return std::make_pair(Kind, std::make_pair(Check, Mask));
1035 }
1036 
1037 void ScalarExprEmitter::EmitIntegerTruncationCheck(Value *Src, QualType SrcType,
1038  Value *Dst, QualType DstType,
1039  SourceLocation Loc) {
1040  if (!CGF.SanOpts.hasOneOf(SanitizerKind::ImplicitIntegerTruncation))
1041  return;
1042 
1043  // We only care about int->int conversions here.
1044  // We ignore conversions to/from pointer and/or bool.
1045  if (!(SrcType->isIntegerType() && DstType->isIntegerType()))
1046  return;
1047 
1048  unsigned SrcBits = Src->getType()->getScalarSizeInBits();
1049  unsigned DstBits = Dst->getType()->getScalarSizeInBits();
1050  // This must be truncation. Else we do not care.
1051  if (SrcBits <= DstBits)
1052  return;
1053 
1054  assert(!DstType->isBooleanType() && "we should not get here with booleans.");
1055 
1056  // If the integer sign change sanitizer is enabled,
1057  // and we are truncating from larger unsigned type to smaller signed type,
1058  // let that next sanitizer deal with it.
1059  bool SrcSigned = SrcType->isSignedIntegerOrEnumerationType();
1060  bool DstSigned = DstType->isSignedIntegerOrEnumerationType();
1061  if (CGF.SanOpts.has(SanitizerKind::ImplicitIntegerSignChange) &&
1062  (!SrcSigned && DstSigned))
1063  return;
1064 
1065  CodeGenFunction::SanitizerScope SanScope(&CGF);
1066 
1067  std::pair<ScalarExprEmitter::ImplicitConversionCheckKind,
1068  std::pair<llvm::Value *, SanitizerMask>>
1069  Check =
1070  EmitIntegerTruncationCheckHelper(Src, SrcType, Dst, DstType, Builder);
1071  // If the comparison result is 'i1 false', then the truncation was lossy.
1072 
1073  // Do we care about this type of truncation?
1074  if (!CGF.SanOpts.has(Check.second.second))
1075  return;
1076 
1077  llvm::Constant *StaticArgs[] = {
1078  CGF.EmitCheckSourceLocation(Loc), CGF.EmitCheckTypeDescriptor(SrcType),
1079  CGF.EmitCheckTypeDescriptor(DstType),
1080  llvm::ConstantInt::get(Builder.getInt8Ty(), Check.first)};
1081  CGF.EmitCheck(Check.second, SanitizerHandler::ImplicitConversion, StaticArgs,
1082  {Src, Dst});
1083 }
1084 
1085 // Should be called within CodeGenFunction::SanitizerScope RAII scope.
1086 // Returns 'i1 false' when the conversion Src -> Dst changed the sign.
1087 static std::pair<ScalarExprEmitter::ImplicitConversionCheckKind,
1088  std::pair<llvm::Value *, SanitizerMask>>
1090  QualType DstType, CGBuilderTy &Builder) {
1091  llvm::Type *SrcTy = Src->getType();
1092  llvm::Type *DstTy = Dst->getType();
1093 
1094  assert(isa<llvm::IntegerType>(SrcTy) && isa<llvm::IntegerType>(DstTy) &&
1095  "non-integer llvm type");
1096 
1097  bool SrcSigned = SrcType->isSignedIntegerOrEnumerationType();
1098  bool DstSigned = DstType->isSignedIntegerOrEnumerationType();
1099  (void)SrcSigned; // Only used in assert()
1100  (void)DstSigned; // Only used in assert()
1101  unsigned SrcBits = SrcTy->getScalarSizeInBits();
1102  unsigned DstBits = DstTy->getScalarSizeInBits();
1103  (void)SrcBits; // Only used in assert()
1104  (void)DstBits; // Only used in assert()
1105 
1106  assert(((SrcBits != DstBits) || (SrcSigned != DstSigned)) &&
1107  "either the widths should be different, or the signednesses.");
1108 
1109  // NOTE: zero value is considered to be non-negative.
1110  auto EmitIsNegativeTest = [&Builder](Value *V, QualType VType,
1111  const char *Name) -> Value * {
1112  // Is this value a signed type?
1113  bool VSigned = VType->isSignedIntegerOrEnumerationType();
1114  llvm::Type *VTy = V->getType();
1115  if (!VSigned) {
1116  // If the value is unsigned, then it is never negative.
1117  // FIXME: can we encounter non-scalar VTy here?
1118  return llvm::ConstantInt::getFalse(VTy->getContext());
1119  }
1120  // Get the zero of the same type with which we will be comparing.
1121  llvm::Constant *Zero = llvm::ConstantInt::get(VTy, 0);
1122  // %V.isnegative = icmp slt %V, 0
1123  // I.e is %V *strictly* less than zero, does it have negative value?
1124  return Builder.CreateICmp(llvm::ICmpInst::ICMP_SLT, V, Zero,
1125  llvm::Twine(Name) + "." + V->getName() +
1126  ".negativitycheck");
1127  };
1128 
1129  // 1. Was the old Value negative?
1130  llvm::Value *SrcIsNegative = EmitIsNegativeTest(Src, SrcType, "src");
1131  // 2. Is the new Value negative?
1132  llvm::Value *DstIsNegative = EmitIsNegativeTest(Dst, DstType, "dst");
1133  // 3. Now, was the 'negativity status' preserved during the conversion?
1134  // NOTE: conversion from negative to zero is considered to change the sign.
1135  // (We want to get 'false' when the conversion changed the sign)
1136  // So we should just equality-compare the negativity statuses.
1137  llvm::Value *Check = nullptr;
1138  Check = Builder.CreateICmpEQ(SrcIsNegative, DstIsNegative, "signchangecheck");
1139  // If the comparison result is 'false', then the conversion changed the sign.
1140  return std::make_pair(
1141  ScalarExprEmitter::ICCK_IntegerSignChange,
1142  std::make_pair(Check, SanitizerKind::ImplicitIntegerSignChange));
1143 }
1144 
1145 void ScalarExprEmitter::EmitIntegerSignChangeCheck(Value *Src, QualType SrcType,
1146  Value *Dst, QualType DstType,
1147  SourceLocation Loc) {
1148  if (!CGF.SanOpts.has(SanitizerKind::ImplicitIntegerSignChange))
1149  return;
1150 
1151  llvm::Type *SrcTy = Src->getType();
1152  llvm::Type *DstTy = Dst->getType();
1153 
1154  // We only care about int->int conversions here.
1155  // We ignore conversions to/from pointer and/or bool.
1156  if (!(SrcType->isIntegerType() && DstType->isIntegerType()))
1157  return;
1158 
1159  bool SrcSigned = SrcType->isSignedIntegerOrEnumerationType();
1160  bool DstSigned = DstType->isSignedIntegerOrEnumerationType();
1161  unsigned SrcBits = SrcTy->getScalarSizeInBits();
1162  unsigned DstBits = DstTy->getScalarSizeInBits();
1163 
1164  // Now, we do not need to emit the check in *all* of the cases.
1165  // We can avoid emitting it in some obvious cases where it would have been
1166  // dropped by the opt passes (instcombine) always anyways.
1167  // If it's a cast between effectively the same type, no check.
1168  // NOTE: this is *not* equivalent to checking the canonical types.
1169  if (SrcSigned == DstSigned && SrcBits == DstBits)
1170  return;
1171  // At least one of the values needs to have signed type.
1172  // If both are unsigned, then obviously, neither of them can be negative.
1173  if (!SrcSigned && !DstSigned)
1174  return;
1175  // If the conversion is to *larger* *signed* type, then no check is needed.
1176  // Because either sign-extension happens (so the sign will remain),
1177  // or zero-extension will happen (the sign bit will be zero.)
1178  if ((DstBits > SrcBits) && DstSigned)
1179  return;
1180  if (CGF.SanOpts.has(SanitizerKind::ImplicitSignedIntegerTruncation) &&
1181  (SrcBits > DstBits) && SrcSigned) {
1182  // If the signed integer truncation sanitizer is enabled,
1183  // and this is a truncation from signed type, then no check is needed.
1184  // Because here sign change check is interchangeable with truncation check.
1185  return;
1186  }
1187  // That's it. We can't rule out any more cases with the data we have.
1188 
1189  CodeGenFunction::SanitizerScope SanScope(&CGF);
1190 
1191  std::pair<ScalarExprEmitter::ImplicitConversionCheckKind,
1192  std::pair<llvm::Value *, SanitizerMask>>
1193  Check;
1194 
1195  // Each of these checks needs to return 'false' when an issue was detected.
1196  ImplicitConversionCheckKind CheckKind;
1198  // So we can 'and' all the checks together, and still get 'false',
1199  // if at least one of the checks detected an issue.
1200 
1201  Check = EmitIntegerSignChangeCheckHelper(Src, SrcType, Dst, DstType, Builder);
1202  CheckKind = Check.first;
1203  Checks.emplace_back(Check.second);
1204 
1205  if (CGF.SanOpts.has(SanitizerKind::ImplicitSignedIntegerTruncation) &&
1206  (SrcBits > DstBits) && !SrcSigned && DstSigned) {
1207  // If the signed integer truncation sanitizer was enabled,
1208  // and we are truncating from larger unsigned type to smaller signed type,
1209  // let's handle the case we skipped in that check.
1210  Check =
1211  EmitIntegerTruncationCheckHelper(Src, SrcType, Dst, DstType, Builder);
1212  CheckKind = ICCK_SignedIntegerTruncationOrSignChange;
1213  Checks.emplace_back(Check.second);
1214  // If the comparison result is 'i1 false', then the truncation was lossy.
1215  }
1216 
1217  llvm::Constant *StaticArgs[] = {
1218  CGF.EmitCheckSourceLocation(Loc), CGF.EmitCheckTypeDescriptor(SrcType),
1219  CGF.EmitCheckTypeDescriptor(DstType),
1220  llvm::ConstantInt::get(Builder.getInt8Ty(), CheckKind)};
1221  // EmitCheck() will 'and' all the checks together.
1222  CGF.EmitCheck(Checks, SanitizerHandler::ImplicitConversion, StaticArgs,
1223  {Src, Dst});
1224 }
1225 
1226 /// Emit a conversion from the specified type to the specified destination type,
1227 /// both of which are LLVM scalar types.
1228 Value *ScalarExprEmitter::EmitScalarConversion(Value *Src, QualType SrcType,
1229  QualType DstType,
1230  SourceLocation Loc,
1231  ScalarConversionOpts Opts) {
1232  // All conversions involving fixed point types should be handled by the
1233  // EmitFixedPoint family functions. This is done to prevent bloating up this
1234  // function more, and although fixed point numbers are represented by
1235  // integers, we do not want to follow any logic that assumes they should be
1236  // treated as integers.
1237  // TODO(leonardchan): When necessary, add another if statement checking for
1238  // conversions to fixed point types from other types.
1239  if (SrcType->isFixedPointType()) {
1240  if (DstType->isBooleanType())
1241  // It is important that we check this before checking if the dest type is
1242  // an integer because booleans are technically integer types.
1243  // We do not need to check the padding bit on unsigned types if unsigned
1244  // padding is enabled because overflow into this bit is undefined
1245  // behavior.
1246  return Builder.CreateIsNotNull(Src, "tobool");
1247  if (DstType->isFixedPointType() || DstType->isIntegerType())
1248  return EmitFixedPointConversion(Src, SrcType, DstType, Loc);
1249 
1250  llvm_unreachable(
1251  "Unhandled scalar conversion from a fixed point type to another type.");
1252  } else if (DstType->isFixedPointType()) {
1253  if (SrcType->isIntegerType())
1254  // This also includes converting booleans and enums to fixed point types.
1255  return EmitFixedPointConversion(Src, SrcType, DstType, Loc);
1256 
1257  llvm_unreachable(
1258  "Unhandled scalar conversion to a fixed point type from another type.");
1259  }
1260 
1261  QualType NoncanonicalSrcType = SrcType;
1262  QualType NoncanonicalDstType = DstType;
1263 
1264  SrcType = CGF.getContext().getCanonicalType(SrcType);
1265  DstType = CGF.getContext().getCanonicalType(DstType);
1266  if (SrcType == DstType) return Src;
1267 
1268  if (DstType->isVoidType()) return nullptr;
1269 
1270  llvm::Value *OrigSrc = Src;
1271  QualType OrigSrcType = SrcType;
1272  llvm::Type *SrcTy = Src->getType();
1273 
1274  // Handle conversions to bool first, they are special: comparisons against 0.
1275  if (DstType->isBooleanType())
1276  return EmitConversionToBool(Src, SrcType);
1277 
1278  llvm::Type *DstTy = ConvertType(DstType);
1279 
1280  // Cast from half through float if half isn't a native type.
1281  if (SrcType->isHalfType() && !CGF.getContext().getLangOpts().NativeHalfType) {
1282  // Cast to FP using the intrinsic if the half type itself isn't supported.
1283  if (DstTy->isFloatingPointTy()) {
1285  return Builder.CreateCall(
1286  CGF.CGM.getIntrinsic(llvm::Intrinsic::convert_from_fp16, DstTy),
1287  Src);
1288  } else {
1289  // Cast to other types through float, using either the intrinsic or FPExt,
1290  // depending on whether the half type itself is supported
1291  // (as opposed to operations on half, available with NativeHalfType).
1293  Src = Builder.CreateCall(
1294  CGF.CGM.getIntrinsic(llvm::Intrinsic::convert_from_fp16,
1295  CGF.CGM.FloatTy),
1296  Src);
1297  } else {
1298  Src = Builder.CreateFPExt(Src, CGF.CGM.FloatTy, "conv");
1299  }
1300  SrcType = CGF.getContext().FloatTy;
1301  SrcTy = CGF.FloatTy;
1302  }
1303  }
1304 
1305  // Ignore conversions like int -> uint.
1306  if (SrcTy == DstTy) {
1307  if (Opts.EmitImplicitIntegerSignChangeChecks)
1308  EmitIntegerSignChangeCheck(Src, NoncanonicalSrcType, Src,
1309  NoncanonicalDstType, Loc);
1310 
1311  return Src;
1312  }
1313 
1314  // Handle pointer conversions next: pointers can only be converted to/from
1315  // other pointers and integers. Check for pointer types in terms of LLVM, as
1316  // some native types (like Obj-C id) may map to a pointer type.
1317  if (auto DstPT = dyn_cast<llvm::PointerType>(DstTy)) {
1318  // The source value may be an integer, or a pointer.
1319  if (isa<llvm::PointerType>(SrcTy))
1320  return Builder.CreateBitCast(Src, DstTy, "conv");
1321 
1322  assert(SrcType->isIntegerType() && "Not ptr->ptr or int->ptr conversion?");
1323  // First, convert to the correct width so that we control the kind of
1324  // extension.
1325  llvm::Type *MiddleTy = CGF.CGM.getDataLayout().getIntPtrType(DstPT);
1326  bool InputSigned = SrcType->isSignedIntegerOrEnumerationType();
1327  llvm::Value* IntResult =
1328  Builder.CreateIntCast(Src, MiddleTy, InputSigned, "conv");
1329  // Then, cast to pointer.
1330  return Builder.CreateIntToPtr(IntResult, DstTy, "conv");
1331  }
1332 
1333  if (isa<llvm::PointerType>(SrcTy)) {
1334  // Must be an ptr to int cast.
1335  assert(isa<llvm::IntegerType>(DstTy) && "not ptr->int?");
1336  return Builder.CreatePtrToInt(Src, DstTy, "conv");
1337  }
1338 
1339  // A scalar can be splatted to an extended vector of the same element type
1340  if (DstType->isExtVectorType() && !SrcType->isVectorType()) {
1341  // Sema should add casts to make sure that the source expression's type is
1342  // the same as the vector's element type (sans qualifiers)
1343  assert(DstType->castAs<ExtVectorType>()->getElementType().getTypePtr() ==
1344  SrcType.getTypePtr() &&
1345  "Splatted expr doesn't match with vector element type?");
1346 
1347  // Splat the element across to all elements
1348  unsigned NumElements = DstTy->getVectorNumElements();
1349  return Builder.CreateVectorSplat(NumElements, Src, "splat");
1350  }
1351 
1352  if (isa<llvm::VectorType>(SrcTy) || isa<llvm::VectorType>(DstTy)) {
1353  // Allow bitcast from vector to integer/fp of the same size.
1354  unsigned SrcSize = SrcTy->getPrimitiveSizeInBits();
1355  unsigned DstSize = DstTy->getPrimitiveSizeInBits();
1356  if (SrcSize == DstSize)
1357  return Builder.CreateBitCast(Src, DstTy, "conv");
1358 
1359  // Conversions between vectors of different sizes are not allowed except
1360  // when vectors of half are involved. Operations on storage-only half
1361  // vectors require promoting half vector operands to float vectors and
1362  // truncating the result, which is either an int or float vector, to a
1363  // short or half vector.
1364 
1365  // Source and destination are both expected to be vectors.
1366  llvm::Type *SrcElementTy = SrcTy->getVectorElementType();
1367  llvm::Type *DstElementTy = DstTy->getVectorElementType();
1368  (void)DstElementTy;
1369 
1370  assert(((SrcElementTy->isIntegerTy() &&
1371  DstElementTy->isIntegerTy()) ||
1372  (SrcElementTy->isFloatingPointTy() &&
1373  DstElementTy->isFloatingPointTy())) &&
1374  "unexpected conversion between a floating-point vector and an "
1375  "integer vector");
1376 
1377  // Truncate an i32 vector to an i16 vector.
1378  if (SrcElementTy->isIntegerTy())
1379  return Builder.CreateIntCast(Src, DstTy, false, "conv");
1380 
1381  // Truncate a float vector to a half vector.
1382  if (SrcSize > DstSize)
1383  return Builder.CreateFPTrunc(Src, DstTy, "conv");
1384 
1385  // Promote a half vector to a float vector.
1386  return Builder.CreateFPExt(Src, DstTy, "conv");
1387  }
1388 
1389  // Finally, we have the arithmetic types: real int/float.
1390  Value *Res = nullptr;
1391  llvm::Type *ResTy = DstTy;
1392 
1393  // An overflowing conversion has undefined behavior if either the source type
1394  // or the destination type is a floating-point type.
1395  if (CGF.SanOpts.has(SanitizerKind::FloatCastOverflow) &&
1396  (OrigSrcType->isFloatingType() || DstType->isFloatingType()))
1397  EmitFloatConversionCheck(OrigSrc, OrigSrcType, Src, SrcType, DstType, DstTy,
1398  Loc);
1399 
1400  // Cast to half through float if half isn't a native type.
1401  if (DstType->isHalfType() && !CGF.getContext().getLangOpts().NativeHalfType) {
1402  // Make sure we cast in a single step if from another FP type.
1403  if (SrcTy->isFloatingPointTy()) {
1404  // Use the intrinsic if the half type itself isn't supported
1405  // (as opposed to operations on half, available with NativeHalfType).
1407  return Builder.CreateCall(
1408  CGF.CGM.getIntrinsic(llvm::Intrinsic::convert_to_fp16, SrcTy), Src);
1409  // If the half type is supported, just use an fptrunc.
1410  return Builder.CreateFPTrunc(Src, DstTy);
1411  }
1412  DstTy = CGF.FloatTy;
1413  }
1414 
1415  if (isa<llvm::IntegerType>(SrcTy)) {
1416  bool InputSigned = SrcType->isSignedIntegerOrEnumerationType();
1417  if (SrcType->isBooleanType() && Opts.TreatBooleanAsSigned) {
1418  InputSigned = true;
1419  }
1420  if (isa<llvm::IntegerType>(DstTy))
1421  Res = Builder.CreateIntCast(Src, DstTy, InputSigned, "conv");
1422  else if (InputSigned)
1423  Res = Builder.CreateSIToFP(Src, DstTy, "conv");
1424  else
1425  Res = Builder.CreateUIToFP(Src, DstTy, "conv");
1426  } else if (isa<llvm::IntegerType>(DstTy)) {
1427  assert(SrcTy->isFloatingPointTy() && "Unknown real conversion");
1428  if (DstType->isSignedIntegerOrEnumerationType())
1429  Res = Builder.CreateFPToSI(Src, DstTy, "conv");
1430  else
1431  Res = Builder.CreateFPToUI(Src, DstTy, "conv");
1432  } else {
1433  assert(SrcTy->isFloatingPointTy() && DstTy->isFloatingPointTy() &&
1434  "Unknown real conversion");
1435  if (DstTy->getTypeID() < SrcTy->getTypeID())
1436  Res = Builder.CreateFPTrunc(Src, DstTy, "conv");
1437  else
1438  Res = Builder.CreateFPExt(Src, DstTy, "conv");
1439  }
1440 
1441  if (DstTy != ResTy) {
1443  assert(ResTy->isIntegerTy(16) && "Only half FP requires extra conversion");
1444  Res = Builder.CreateCall(
1445  CGF.CGM.getIntrinsic(llvm::Intrinsic::convert_to_fp16, CGF.CGM.FloatTy),
1446  Res);
1447  } else {
1448  Res = Builder.CreateFPTrunc(Res, ResTy, "conv");
1449  }
1450  }
1451 
1452  if (Opts.EmitImplicitIntegerTruncationChecks)
1453  EmitIntegerTruncationCheck(Src, NoncanonicalSrcType, Res,
1454  NoncanonicalDstType, Loc);
1455 
1456  if (Opts.EmitImplicitIntegerSignChangeChecks)
1457  EmitIntegerSignChangeCheck(Src, NoncanonicalSrcType, Res,
1458  NoncanonicalDstType, Loc);
1459 
1460  return Res;
1461 }
1462 
1463 Value *ScalarExprEmitter::EmitFixedPointConversion(Value *Src, QualType SrcTy,
1464  QualType DstTy,
1465  SourceLocation Loc) {
1466  FixedPointSemantics SrcFPSema =
1467  CGF.getContext().getFixedPointSemantics(SrcTy);
1468  FixedPointSemantics DstFPSema =
1469  CGF.getContext().getFixedPointSemantics(DstTy);
1470  return EmitFixedPointConversion(Src, SrcFPSema, DstFPSema, Loc,
1471  DstTy->isIntegerType());
1472 }
1473 
1474 Value *ScalarExprEmitter::EmitFixedPointConversion(
1475  Value *Src, FixedPointSemantics &SrcFPSema, FixedPointSemantics &DstFPSema,
1476  SourceLocation Loc, bool DstIsInteger) {
1477  using llvm::APInt;
1478  using llvm::ConstantInt;
1479  using llvm::Value;
1480 
1481  unsigned SrcWidth = SrcFPSema.getWidth();
1482  unsigned DstWidth = DstFPSema.getWidth();
1483  unsigned SrcScale = SrcFPSema.getScale();
1484  unsigned DstScale = DstFPSema.getScale();
1485  bool SrcIsSigned = SrcFPSema.isSigned();
1486  bool DstIsSigned = DstFPSema.isSigned();
1487 
1488  llvm::Type *DstIntTy = Builder.getIntNTy(DstWidth);
1489 
1490  Value *Result = Src;
1491  unsigned ResultWidth = SrcWidth;
1492 
1493  // Downscale.
1494  if (DstScale < SrcScale) {
1495  // When converting to integers, we round towards zero. For negative numbers,
1496  // right shifting rounds towards negative infinity. In this case, we can
1497  // just round up before shifting.
1498  if (DstIsInteger && SrcIsSigned) {
1499  Value *Zero = llvm::Constant::getNullValue(Result->getType());
1500  Value *IsNegative = Builder.CreateICmpSLT(Result, Zero);
1501  Value *LowBits = ConstantInt::get(
1502  CGF.getLLVMContext(), APInt::getLowBitsSet(ResultWidth, SrcScale));
1503  Value *Rounded = Builder.CreateAdd(Result, LowBits);
1504  Result = Builder.CreateSelect(IsNegative, Rounded, Result);
1505  }
1506 
1507  Result = SrcIsSigned
1508  ? Builder.CreateAShr(Result, SrcScale - DstScale, "downscale")
1509  : Builder.CreateLShr(Result, SrcScale - DstScale, "downscale");
1510  }
1511 
1512  if (!DstFPSema.isSaturated()) {
1513  // Resize.
1514  Result = Builder.CreateIntCast(Result, DstIntTy, SrcIsSigned, "resize");
1515 
1516  // Upscale.
1517  if (DstScale > SrcScale)
1518  Result = Builder.CreateShl(Result, DstScale - SrcScale, "upscale");
1519  } else {
1520  // Adjust the number of fractional bits.
1521  if (DstScale > SrcScale) {
1522  // Compare to DstWidth to prevent resizing twice.
1523  ResultWidth = std::max(SrcWidth + DstScale - SrcScale, DstWidth);
1524  llvm::Type *UpscaledTy = Builder.getIntNTy(ResultWidth);
1525  Result = Builder.CreateIntCast(Result, UpscaledTy, SrcIsSigned, "resize");
1526  Result = Builder.CreateShl(Result, DstScale - SrcScale, "upscale");
1527  }
1528 
1529  // Handle saturation.
1530  bool LessIntBits = DstFPSema.getIntegralBits() < SrcFPSema.getIntegralBits();
1531  if (LessIntBits) {
1532  Value *Max = ConstantInt::get(
1533  CGF.getLLVMContext(),
1534  APFixedPoint::getMax(DstFPSema).getValue().extOrTrunc(ResultWidth));
1535  Value *TooHigh = SrcIsSigned ? Builder.CreateICmpSGT(Result, Max)
1536  : Builder.CreateICmpUGT(Result, Max);
1537  Result = Builder.CreateSelect(TooHigh, Max, Result, "satmax");
1538  }
1539  // Cannot overflow min to dest type if src is unsigned since all fixed
1540  // point types can cover the unsigned min of 0.
1541  if (SrcIsSigned && (LessIntBits || !DstIsSigned)) {
1542  Value *Min = ConstantInt::get(
1543  CGF.getLLVMContext(),
1544  APFixedPoint::getMin(DstFPSema).getValue().extOrTrunc(ResultWidth));
1545  Value *TooLow = Builder.CreateICmpSLT(Result, Min);
1546  Result = Builder.CreateSelect(TooLow, Min, Result, "satmin");
1547  }
1548 
1549  // Resize the integer part to get the final destination size.
1550  if (ResultWidth != DstWidth)
1551  Result = Builder.CreateIntCast(Result, DstIntTy, SrcIsSigned, "resize");
1552  }
1553  return Result;
1554 }
1555 
1556 /// Emit a conversion from the specified complex type to the specified
1557 /// destination type, where the destination type is an LLVM scalar type.
1558 Value *ScalarExprEmitter::EmitComplexToScalarConversion(
1560  SourceLocation Loc) {
1561  // Get the source element type.
1562  SrcTy = SrcTy->castAs<ComplexType>()->getElementType();
1563 
1564  // Handle conversions to bool first, they are special: comparisons against 0.
1565  if (DstTy->isBooleanType()) {
1566  // Complex != 0 -> (Real != 0) | (Imag != 0)
1567  Src.first = EmitScalarConversion(Src.first, SrcTy, DstTy, Loc);
1568  Src.second = EmitScalarConversion(Src.second, SrcTy, DstTy, Loc);
1569  return Builder.CreateOr(Src.first, Src.second, "tobool");
1570  }
1571 
1572  // C99 6.3.1.7p2: "When a value of complex type is converted to a real type,
1573  // the imaginary part of the complex value is discarded and the value of the
1574  // real part is converted according to the conversion rules for the
1575  // corresponding real type.
1576  return EmitScalarConversion(Src.first, SrcTy, DstTy, Loc);
1577 }
1578 
1579 Value *ScalarExprEmitter::EmitNullValue(QualType Ty) {
1580  return CGF.EmitFromMemory(CGF.CGM.EmitNullConstant(Ty), Ty);
1581 }
1582 
1583 /// Emit a sanitization check for the given "binary" operation (which
1584 /// might actually be a unary increment which has been lowered to a binary
1585 /// operation). The check passes if all values in \p Checks (which are \c i1),
1586 /// are \c true.
1587 void ScalarExprEmitter::EmitBinOpCheck(
1588  ArrayRef<std::pair<Value *, SanitizerMask>> Checks, const BinOpInfo &Info) {
1589  assert(CGF.IsSanitizerScope);
1590  SanitizerHandler Check;
1592  SmallVector<llvm::Value *, 2> DynamicData;
1593 
1594  BinaryOperatorKind Opcode = Info.Opcode;
1597 
1598  StaticData.push_back(CGF.EmitCheckSourceLocation(Info.E->getExprLoc()));
1599  const UnaryOperator *UO = dyn_cast<UnaryOperator>(Info.E);
1600  if (UO && UO->getOpcode() == UO_Minus) {
1601  Check = SanitizerHandler::NegateOverflow;
1602  StaticData.push_back(CGF.EmitCheckTypeDescriptor(UO->getType()));
1603  DynamicData.push_back(Info.RHS);
1604  } else {
1605  if (BinaryOperator::isShiftOp(Opcode)) {
1606  // Shift LHS negative or too large, or RHS out of bounds.
1607  Check = SanitizerHandler::ShiftOutOfBounds;
1608  const BinaryOperator *BO = cast<BinaryOperator>(Info.E);
1609  StaticData.push_back(
1610  CGF.EmitCheckTypeDescriptor(BO->getLHS()->getType()));
1611  StaticData.push_back(
1612  CGF.EmitCheckTypeDescriptor(BO->getRHS()->getType()));
1613  } else if (Opcode == BO_Div || Opcode == BO_Rem) {
1614  // Divide or modulo by zero, or signed overflow (eg INT_MAX / -1).
1615  Check = SanitizerHandler::DivremOverflow;
1616  StaticData.push_back(CGF.EmitCheckTypeDescriptor(Info.Ty));
1617  } else {
1618  // Arithmetic overflow (+, -, *).
1619  switch (Opcode) {
1620  case BO_Add: Check = SanitizerHandler::AddOverflow; break;
1621  case BO_Sub: Check = SanitizerHandler::SubOverflow; break;
1622  case BO_Mul: Check = SanitizerHandler::MulOverflow; break;
1623  default: llvm_unreachable("unexpected opcode for bin op check");
1624  }
1625  StaticData.push_back(CGF.EmitCheckTypeDescriptor(Info.Ty));
1626  }
1627  DynamicData.push_back(Info.LHS);
1628  DynamicData.push_back(Info.RHS);
1629  }
1630 
1631  CGF.EmitCheck(Checks, Check, StaticData, DynamicData);
1632 }
1633 
1634 //===----------------------------------------------------------------------===//
1635 // Visitor Methods
1636 //===----------------------------------------------------------------------===//
1637 
1638 Value *ScalarExprEmitter::VisitExpr(Expr *E) {
1639  CGF.ErrorUnsupported(E, "scalar expression");
1640  if (E->getType()->isVoidType())
1641  return nullptr;
1642  return llvm::UndefValue::get(CGF.ConvertType(E->getType()));
1643 }
1644 
1645 Value *ScalarExprEmitter::VisitShuffleVectorExpr(ShuffleVectorExpr *E) {
1646  // Vector Mask Case
1647  if (E->getNumSubExprs() == 2) {
1648  Value *LHS = CGF.EmitScalarExpr(E->getExpr(0));
1649  Value *RHS = CGF.EmitScalarExpr(E->getExpr(1));
1650  Value *Mask;
1651 
1652  llvm::VectorType *LTy = cast<llvm::VectorType>(LHS->getType());
1653  unsigned LHSElts = LTy->getNumElements();
1654 
1655  Mask = RHS;
1656 
1657  llvm::VectorType *MTy = cast<llvm::VectorType>(Mask->getType());
1658 
1659  // Mask off the high bits of each shuffle index.
1660  Value *MaskBits =
1661  llvm::ConstantInt::get(MTy, llvm::NextPowerOf2(LHSElts - 1) - 1);
1662  Mask = Builder.CreateAnd(Mask, MaskBits, "mask");
1663 
1664  // newv = undef
1665  // mask = mask & maskbits
1666  // for each elt
1667  // n = extract mask i
1668  // x = extract val n
1669  // newv = insert newv, x, i
1670  llvm::VectorType *RTy = llvm::VectorType::get(LTy->getElementType(),
1671  MTy->getNumElements());
1672  Value* NewV = llvm::UndefValue::get(RTy);
1673  for (unsigned i = 0, e = MTy->getNumElements(); i != e; ++i) {
1674  Value *IIndx = llvm::ConstantInt::get(CGF.SizeTy, i);
1675  Value *Indx = Builder.CreateExtractElement(Mask, IIndx, "shuf_idx");
1676 
1677  Value *VExt = Builder.CreateExtractElement(LHS, Indx, "shuf_elt");
1678  NewV = Builder.CreateInsertElement(NewV, VExt, IIndx, "shuf_ins");
1679  }
1680  return NewV;
1681  }
1682 
1683  Value* V1 = CGF.EmitScalarExpr(E->getExpr(0));
1684  Value* V2 = CGF.EmitScalarExpr(E->getExpr(1));
1685 
1687  for (unsigned i = 2; i < E->getNumSubExprs(); ++i) {
1688  llvm::APSInt Idx = E->getShuffleMaskIdx(CGF.getContext(), i-2);
1689  // Check for -1 and output it as undef in the IR.
1690  if (Idx.isSigned() && Idx.isAllOnesValue())
1691  indices.push_back(llvm::UndefValue::get(CGF.Int32Ty));
1692  else
1693  indices.push_back(Builder.getInt32(Idx.getZExtValue()));
1694  }
1695 
1696  Value *SV = llvm::ConstantVector::get(indices);
1697  return Builder.CreateShuffleVector(V1, V2, SV, "shuffle");
1698 }
1699 
1700 Value *ScalarExprEmitter::VisitConvertVectorExpr(ConvertVectorExpr *E) {
1701  QualType SrcType = E->getSrcExpr()->getType(),
1702  DstType = E->getType();
1703 
1704  Value *Src = CGF.EmitScalarExpr(E->getSrcExpr());
1705 
1706  SrcType = CGF.getContext().getCanonicalType(SrcType);
1707  DstType = CGF.getContext().getCanonicalType(DstType);
1708  if (SrcType == DstType) return Src;
1709 
1710  assert(SrcType->isVectorType() &&
1711  "ConvertVector source type must be a vector");
1712  assert(DstType->isVectorType() &&
1713  "ConvertVector destination type must be a vector");
1714 
1715  llvm::Type *SrcTy = Src->getType();
1716  llvm::Type *DstTy = ConvertType(DstType);
1717 
1718  // Ignore conversions like int -> uint.
1719  if (SrcTy == DstTy)
1720  return Src;
1721 
1722  QualType SrcEltType = SrcType->getAs<VectorType>()->getElementType(),
1723  DstEltType = DstType->getAs<VectorType>()->getElementType();
1724 
1725  assert(SrcTy->isVectorTy() &&
1726  "ConvertVector source IR type must be a vector");
1727  assert(DstTy->isVectorTy() &&
1728  "ConvertVector destination IR type must be a vector");
1729 
1730  llvm::Type *SrcEltTy = SrcTy->getVectorElementType(),
1731  *DstEltTy = DstTy->getVectorElementType();
1732 
1733  if (DstEltType->isBooleanType()) {
1734  assert((SrcEltTy->isFloatingPointTy() ||
1735  isa<llvm::IntegerType>(SrcEltTy)) && "Unknown boolean conversion");
1736 
1737  llvm::Value *Zero = llvm::Constant::getNullValue(SrcTy);
1738  if (SrcEltTy->isFloatingPointTy()) {
1739  return Builder.CreateFCmpUNE(Src, Zero, "tobool");
1740  } else {
1741  return Builder.CreateICmpNE(Src, Zero, "tobool");
1742  }
1743  }
1744 
1745  // We have the arithmetic types: real int/float.
1746  Value *Res = nullptr;
1747 
1748  if (isa<llvm::IntegerType>(SrcEltTy)) {
1749  bool InputSigned = SrcEltType->isSignedIntegerOrEnumerationType();
1750  if (isa<llvm::IntegerType>(DstEltTy))
1751  Res = Builder.CreateIntCast(Src, DstTy, InputSigned, "conv");
1752  else if (InputSigned)
1753  Res = Builder.CreateSIToFP(Src, DstTy, "conv");
1754  else
1755  Res = Builder.CreateUIToFP(Src, DstTy, "conv");
1756  } else if (isa<llvm::IntegerType>(DstEltTy)) {
1757  assert(SrcEltTy->isFloatingPointTy() && "Unknown real conversion");
1758  if (DstEltType->isSignedIntegerOrEnumerationType())
1759  Res = Builder.CreateFPToSI(Src, DstTy, "conv");
1760  else
1761  Res = Builder.CreateFPToUI(Src, DstTy, "conv");
1762  } else {
1763  assert(SrcEltTy->isFloatingPointTy() && DstEltTy->isFloatingPointTy() &&
1764  "Unknown real conversion");
1765  if (DstEltTy->getTypeID() < SrcEltTy->getTypeID())
1766  Res = Builder.CreateFPTrunc(Src, DstTy, "conv");
1767  else
1768  Res = Builder.CreateFPExt(Src, DstTy, "conv");
1769  }
1770 
1771  return Res;
1772 }
1773 
1774 Value *ScalarExprEmitter::VisitMemberExpr(MemberExpr *E) {
1775  if (CodeGenFunction::ConstantEmission Constant = CGF.tryEmitAsConstant(E)) {
1776  CGF.EmitIgnoredExpr(E->getBase());
1777  return CGF.emitScalarConstant(Constant, E);
1778  } else {
1779  Expr::EvalResult Result;
1780  if (E->EvaluateAsInt(Result, CGF.getContext(), Expr::SE_AllowSideEffects)) {
1781  llvm::APSInt Value = Result.Val.getInt();
1782  CGF.EmitIgnoredExpr(E->getBase());
1783  return Builder.getInt(Value);
1784  }
1785  }
1786 
1787  return EmitLoadOfLValue(E);
1788 }
1789 
1790 Value *ScalarExprEmitter::VisitArraySubscriptExpr(ArraySubscriptExpr *E) {
1791  TestAndClearIgnoreResultAssign();
1792 
1793  // Emit subscript expressions in rvalue context's. For most cases, this just
1794  // loads the lvalue formed by the subscript expr. However, we have to be
1795  // careful, because the base of a vector subscript is occasionally an rvalue,
1796  // so we can't get it as an lvalue.
1797  if (!E->getBase()->getType()->isVectorType())
1798  return EmitLoadOfLValue(E);
1799 
1800  // Handle the vector case. The base must be a vector, the index must be an
1801  // integer value.
1802  Value *Base = Visit(E->getBase());
1803  Value *Idx = Visit(E->getIdx());
1804  QualType IdxTy = E->getIdx()->getType();
1805 
1806  if (CGF.SanOpts.has(SanitizerKind::ArrayBounds))
1807  CGF.EmitBoundsCheck(E, E->getBase(), Idx, IdxTy, /*Accessed*/true);
1808 
1809  return Builder.CreateExtractElement(Base, Idx, "vecext");
1810 }
1811 
1812 static llvm::Constant *getMaskElt(llvm::ShuffleVectorInst *SVI, unsigned Idx,
1813  unsigned Off, llvm::Type *I32Ty) {
1814  int MV = SVI->getMaskValue(Idx);
1815  if (MV == -1)
1816  return llvm::UndefValue::get(I32Ty);
1817  return llvm::ConstantInt::get(I32Ty, Off+MV);
1818 }
1819 
1820 static llvm::Constant *getAsInt32(llvm::ConstantInt *C, llvm::Type *I32Ty) {
1821  if (C->getBitWidth() != 32) {
1822  assert(llvm::ConstantInt::isValueValidForType(I32Ty,
1823  C->getZExtValue()) &&
1824  "Index operand too large for shufflevector mask!");
1825  return llvm::ConstantInt::get(I32Ty, C->getZExtValue());
1826  }
1827  return C;
1828 }
1829 
1830 Value *ScalarExprEmitter::VisitInitListExpr(InitListExpr *E) {
1831  bool Ignore = TestAndClearIgnoreResultAssign();
1832  (void)Ignore;
1833  assert (Ignore == false && "init list ignored");
1834  unsigned NumInitElements = E->getNumInits();
1835 
1836  if (E->hadArrayRangeDesignator())
1837  CGF.ErrorUnsupported(E, "GNU array range designator extension");
1838 
1839  llvm::VectorType *VType =
1840  dyn_cast<llvm::VectorType>(ConvertType(E->getType()));
1841 
1842  if (!VType) {
1843  if (NumInitElements == 0) {
1844  // C++11 value-initialization for the scalar.
1845  return EmitNullValue(E->getType());
1846  }
1847  // We have a scalar in braces. Just use the first element.
1848  return Visit(E->getInit(0));
1849  }
1850 
1851  unsigned ResElts = VType->getNumElements();
1852 
1853  // Loop over initializers collecting the Value for each, and remembering
1854  // whether the source was swizzle (ExtVectorElementExpr). This will allow
1855  // us to fold the shuffle for the swizzle into the shuffle for the vector
1856  // initializer, since LLVM optimizers generally do not want to touch
1857  // shuffles.
1858  unsigned CurIdx = 0;
1859  bool VIsUndefShuffle = false;
1860  llvm::Value *V = llvm::UndefValue::get(VType);
1861  for (unsigned i = 0; i != NumInitElements; ++i) {
1862  Expr *IE = E->getInit(i);
1863  Value *Init = Visit(IE);
1865 
1866  llvm::VectorType *VVT = dyn_cast<llvm::VectorType>(Init->getType());
1867 
1868  // Handle scalar elements. If the scalar initializer is actually one
1869  // element of a different vector of the same width, use shuffle instead of
1870  // extract+insert.
1871  if (!VVT) {
1872  if (isa<ExtVectorElementExpr>(IE)) {
1873  llvm::ExtractElementInst *EI = cast<llvm::ExtractElementInst>(Init);
1874 
1875  if (EI->getVectorOperandType()->getNumElements() == ResElts) {
1876  llvm::ConstantInt *C = cast<llvm::ConstantInt>(EI->getIndexOperand());
1877  Value *LHS = nullptr, *RHS = nullptr;
1878  if (CurIdx == 0) {
1879  // insert into undef -> shuffle (src, undef)
1880  // shufflemask must use an i32
1881  Args.push_back(getAsInt32(C, CGF.Int32Ty));
1882  Args.resize(ResElts, llvm::UndefValue::get(CGF.Int32Ty));
1883 
1884  LHS = EI->getVectorOperand();
1885  RHS = V;
1886  VIsUndefShuffle = true;
1887  } else if (VIsUndefShuffle) {
1888  // insert into undefshuffle && size match -> shuffle (v, src)
1889  llvm::ShuffleVectorInst *SVV = cast<llvm::ShuffleVectorInst>(V);
1890  for (unsigned j = 0; j != CurIdx; ++j)
1891  Args.push_back(getMaskElt(SVV, j, 0, CGF.Int32Ty));
1892  Args.push_back(Builder.getInt32(ResElts + C->getZExtValue()));
1893  Args.resize(ResElts, llvm::UndefValue::get(CGF.Int32Ty));
1894 
1895  LHS = cast<llvm::ShuffleVectorInst>(V)->getOperand(0);
1896  RHS = EI->getVectorOperand();
1897  VIsUndefShuffle = false;
1898  }
1899  if (!Args.empty()) {
1900  llvm::Constant *Mask = llvm::ConstantVector::get(Args);
1901  V = Builder.CreateShuffleVector(LHS, RHS, Mask);
1902  ++CurIdx;
1903  continue;
1904  }
1905  }
1906  }
1907  V = Builder.CreateInsertElement(V, Init, Builder.getInt32(CurIdx),
1908  "vecinit");
1909  VIsUndefShuffle = false;
1910  ++CurIdx;
1911  continue;
1912  }
1913 
1914  unsigned InitElts = VVT->getNumElements();
1915 
1916  // If the initializer is an ExtVecEltExpr (a swizzle), and the swizzle's
1917  // input is the same width as the vector being constructed, generate an
1918  // optimized shuffle of the swizzle input into the result.
1919  unsigned Offset = (CurIdx == 0) ? 0 : ResElts;
1920  if (isa<ExtVectorElementExpr>(IE)) {
1921  llvm::ShuffleVectorInst *SVI = cast<llvm::ShuffleVectorInst>(Init);
1922  Value *SVOp = SVI->getOperand(0);
1923  llvm::VectorType *OpTy = cast<llvm::VectorType>(SVOp->getType());
1924 
1925  if (OpTy->getNumElements() == ResElts) {
1926  for (unsigned j = 0; j != CurIdx; ++j) {
1927  // If the current vector initializer is a shuffle with undef, merge
1928  // this shuffle directly into it.
1929  if (VIsUndefShuffle) {
1930  Args.push_back(getMaskElt(cast<llvm::ShuffleVectorInst>(V), j, 0,
1931  CGF.Int32Ty));
1932  } else {
1933  Args.push_back(Builder.getInt32(j));
1934  }
1935  }
1936  for (unsigned j = 0, je = InitElts; j != je; ++j)
1937  Args.push_back(getMaskElt(SVI, j, Offset, CGF.Int32Ty));
1938  Args.resize(ResElts, llvm::UndefValue::get(CGF.Int32Ty));
1939 
1940  if (VIsUndefShuffle)
1941  V = cast<llvm::ShuffleVectorInst>(V)->getOperand(0);
1942 
1943  Init = SVOp;
1944  }
1945  }
1946 
1947  // Extend init to result vector length, and then shuffle its contribution
1948  // to the vector initializer into V.
1949  if (Args.empty()) {
1950  for (unsigned j = 0; j != InitElts; ++j)
1951  Args.push_back(Builder.getInt32(j));
1952  Args.resize(ResElts, llvm::UndefValue::get(CGF.Int32Ty));
1953  llvm::Constant *Mask = llvm::ConstantVector::get(Args);
1954  Init = Builder.CreateShuffleVector(Init, llvm::UndefValue::get(VVT),
1955  Mask, "vext");
1956 
1957  Args.clear();
1958  for (unsigned j = 0; j != CurIdx; ++j)
1959  Args.push_back(Builder.getInt32(j));
1960  for (unsigned j = 0; j != InitElts; ++j)
1961  Args.push_back(Builder.getInt32(j+Offset));
1962  Args.resize(ResElts, llvm::UndefValue::get(CGF.Int32Ty));
1963  }
1964 
1965  // If V is undef, make sure it ends up on the RHS of the shuffle to aid
1966  // merging subsequent shuffles into this one.
1967  if (CurIdx == 0)
1968  std::swap(V, Init);
1969  llvm::Constant *Mask = llvm::ConstantVector::get(Args);
1970  V = Builder.CreateShuffleVector(V, Init, Mask, "vecinit");
1971  VIsUndefShuffle = isa<llvm::UndefValue>(Init);
1972  CurIdx += InitElts;
1973  }
1974 
1975  // FIXME: evaluate codegen vs. shuffling against constant null vector.
1976  // Emit remaining default initializers.
1977  llvm::Type *EltTy = VType->getElementType();
1978 
1979  // Emit remaining default initializers
1980  for (/* Do not initialize i*/; CurIdx < ResElts; ++CurIdx) {
1981  Value *Idx = Builder.getInt32(CurIdx);
1982  llvm::Value *Init = llvm::Constant::getNullValue(EltTy);
1983  V = Builder.CreateInsertElement(V, Init, Idx, "vecinit");
1984  }
1985  return V;
1986 }
1987 
1989  const Expr *E = CE->getSubExpr();
1990 
1991  if (CE->getCastKind() == CK_UncheckedDerivedToBase)
1992  return false;
1993 
1994  if (isa<CXXThisExpr>(E->IgnoreParens())) {
1995  // We always assume that 'this' is never null.
1996  return false;
1997  }
1998 
1999  if (const ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(CE)) {
2000  // And that glvalue casts are never null.
2001  if (ICE->getValueKind() != VK_RValue)
2002  return false;
2003  }
2004 
2005  return true;
2006 }
2007 
2008 // VisitCastExpr - Emit code for an explicit or implicit cast. Implicit casts
2009 // have to handle a more broad range of conversions than explicit casts, as they
2010 // handle things like function to ptr-to-function decay etc.
2011 Value *ScalarExprEmitter::VisitCastExpr(CastExpr *CE) {
2012  Expr *E = CE->getSubExpr();
2013  QualType DestTy = CE->getType();
2014  CastKind Kind = CE->getCastKind();
2015 
2016  // These cases are generally not written to ignore the result of
2017  // evaluating their sub-expressions, so we clear this now.
2018  bool Ignored = TestAndClearIgnoreResultAssign();
2019 
2020  // Since almost all cast kinds apply to scalars, this switch doesn't have
2021  // a default case, so the compiler will warn on a missing case. The cases
2022  // are in the same order as in the CastKind enum.
2023  switch (Kind) {
2024  case CK_Dependent: llvm_unreachable("dependent cast kind in IR gen!");
2025  case CK_BuiltinFnToFnPtr:
2026  llvm_unreachable("builtin functions are handled elsewhere");
2027 
2028  case CK_LValueBitCast:
2029  case CK_ObjCObjectLValueCast: {
2030  Address Addr = EmitLValue(E).getAddress();
2031  Addr = Builder.CreateElementBitCast(Addr, CGF.ConvertTypeForMem(DestTy));
2032  LValue LV = CGF.MakeAddrLValue(Addr, DestTy);
2033  return EmitLoadOfLValue(LV, CE->getExprLoc());
2034  }
2035 
2036  case CK_CPointerToObjCPointerCast:
2037  case CK_BlockPointerToObjCPointerCast:
2038  case CK_AnyPointerToBlockPointerCast:
2039  case CK_BitCast: {
2040  Value *Src = Visit(const_cast<Expr*>(E));
2041  llvm::Type *SrcTy = Src->getType();
2042  llvm::Type *DstTy = ConvertType(DestTy);
2043  if (SrcTy->isPtrOrPtrVectorTy() && DstTy->isPtrOrPtrVectorTy() &&
2044  SrcTy->getPointerAddressSpace() != DstTy->getPointerAddressSpace()) {
2045  llvm_unreachable("wrong cast for pointers in different address spaces"
2046  "(must be an address space cast)!");
2047  }
2048 
2049  if (CGF.SanOpts.has(SanitizerKind::CFIUnrelatedCast)) {
2050  if (auto PT = DestTy->getAs<PointerType>())
2051  CGF.EmitVTablePtrCheckForCast(PT->getPointeeType(), Src,
2052  /*MayBeNull=*/true,
2054  CE->getBeginLoc());
2055  }
2056 
2057  if (CGF.CGM.getCodeGenOpts().StrictVTablePointers) {
2058  const QualType SrcType = E->getType();
2059 
2060  if (SrcType.mayBeNotDynamicClass() && DestTy.mayBeDynamicClass()) {
2061  // Casting to pointer that could carry dynamic information (provided by
2062  // invariant.group) requires launder.
2063  Src = Builder.CreateLaunderInvariantGroup(Src);
2064  } else if (SrcType.mayBeDynamicClass() && DestTy.mayBeNotDynamicClass()) {
2065  // Casting to pointer that does not carry dynamic information (provided
2066  // by invariant.group) requires stripping it. Note that we don't do it
2067  // if the source could not be dynamic type and destination could be
2068  // dynamic because dynamic information is already laundered. It is
2069  // because launder(strip(src)) == launder(src), so there is no need to
2070  // add extra strip before launder.
2071  Src = Builder.CreateStripInvariantGroup(Src);
2072  }
2073  }
2074 
2075  // Update heapallocsite metadata when there is an explicit cast.
2076  if (llvm::CallInst *CI = dyn_cast<llvm::CallInst>(Src))
2077  if (CI->getMetadata("heapallocsite") && isa<ExplicitCastExpr>(CE))
2078  CGF.getDebugInfo()->
2079  addHeapAllocSiteMetadata(CI, CE->getType(), CE->getExprLoc());
2080 
2081  return Builder.CreateBitCast(Src, DstTy);
2082  }
2083  case CK_AddressSpaceConversion: {
2084  Expr::EvalResult Result;
2085  if (E->EvaluateAsRValue(Result, CGF.getContext()) &&
2086  Result.Val.isNullPointer()) {
2087  // If E has side effect, it is emitted even if its final result is a
2088  // null pointer. In that case, a DCE pass should be able to
2089  // eliminate the useless instructions emitted during translating E.
2090  if (Result.HasSideEffects)
2091  Visit(E);
2092  return CGF.CGM.getNullPointer(cast<llvm::PointerType>(
2093  ConvertType(DestTy)), DestTy);
2094  }
2095  // Since target may map different address spaces in AST to the same address
2096  // space, an address space conversion may end up as a bitcast.
2098  CGF, Visit(E), E->getType()->getPointeeType().getAddressSpace(),
2099  DestTy->getPointeeType().getAddressSpace(), ConvertType(DestTy));
2100  }
2101  case CK_AtomicToNonAtomic:
2102  case CK_NonAtomicToAtomic:
2103  case CK_NoOp:
2104  case CK_UserDefinedConversion:
2105  return Visit(const_cast<Expr*>(E));
2106 
2107  case CK_BaseToDerived: {
2108  const CXXRecordDecl *DerivedClassDecl = DestTy->getPointeeCXXRecordDecl();
2109  assert(DerivedClassDecl && "BaseToDerived arg isn't a C++ object pointer!");
2110 
2111  Address Base = CGF.EmitPointerWithAlignment(E);
2112  Address Derived =
2113  CGF.GetAddressOfDerivedClass(Base, DerivedClassDecl,
2114  CE->path_begin(), CE->path_end(),
2116 
2117  // C++11 [expr.static.cast]p11: Behavior is undefined if a downcast is
2118  // performed and the object is not of the derived type.
2119  if (CGF.sanitizePerformTypeCheck())
2121  Derived.getPointer(), DestTy->getPointeeType());
2122 
2123  if (CGF.SanOpts.has(SanitizerKind::CFIDerivedCast))
2125  DestTy->getPointeeType(), Derived.getPointer(),
2126  /*MayBeNull=*/true, CodeGenFunction::CFITCK_DerivedCast,
2127  CE->getBeginLoc());
2128 
2129  return Derived.getPointer();
2130  }
2131  case CK_UncheckedDerivedToBase:
2132  case CK_DerivedToBase: {
2133  // The EmitPointerWithAlignment path does this fine; just discard
2134  // the alignment.
2135  return CGF.EmitPointerWithAlignment(CE).getPointer();
2136  }
2137 
2138  case CK_Dynamic: {
2139  Address V = CGF.EmitPointerWithAlignment(E);
2140  const CXXDynamicCastExpr *DCE = cast<CXXDynamicCastExpr>(CE);
2141  return CGF.EmitDynamicCast(V, DCE);
2142  }
2143 
2144  case CK_ArrayToPointerDecay:
2145  return CGF.EmitArrayToPointerDecay(E).getPointer();
2146  case CK_FunctionToPointerDecay:
2147  return EmitLValue(E).getPointer();
2148 
2149  case CK_NullToPointer:
2150  if (MustVisitNullValue(E))
2151  CGF.EmitIgnoredExpr(E);
2152 
2153  return CGF.CGM.getNullPointer(cast<llvm::PointerType>(ConvertType(DestTy)),
2154  DestTy);
2155 
2156  case CK_NullToMemberPointer: {
2157  if (MustVisitNullValue(E))
2158  CGF.EmitIgnoredExpr(E);
2159 
2160  const MemberPointerType *MPT = CE->getType()->getAs<MemberPointerType>();
2161  return CGF.CGM.getCXXABI().EmitNullMemberPointer(MPT);
2162  }
2163 
2164  case CK_ReinterpretMemberPointer:
2165  case CK_BaseToDerivedMemberPointer:
2166  case CK_DerivedToBaseMemberPointer: {
2167  Value *Src = Visit(E);
2168 
2169  // Note that the AST doesn't distinguish between checked and
2170  // unchecked member pointer conversions, so we always have to
2171  // implement checked conversions here. This is inefficient when
2172  // actual control flow may be required in order to perform the
2173  // check, which it is for data member pointers (but not member
2174  // function pointers on Itanium and ARM).
2175  return CGF.CGM.getCXXABI().EmitMemberPointerConversion(CGF, CE, Src);
2176  }
2177 
2178  case CK_ARCProduceObject:
2179  return CGF.EmitARCRetainScalarExpr(E);
2180  case CK_ARCConsumeObject:
2181  return CGF.EmitObjCConsumeObject(E->getType(), Visit(E));
2182  case CK_ARCReclaimReturnedObject:
2183  return CGF.EmitARCReclaimReturnedObject(E, /*allowUnsafe*/ Ignored);
2184  case CK_ARCExtendBlockObject:
2185  return CGF.EmitARCExtendBlockObject(E);
2186 
2187  case CK_CopyAndAutoreleaseBlockObject:
2188  return CGF.EmitBlockCopyAndAutorelease(Visit(E), E->getType());
2189 
2190  case CK_FloatingRealToComplex:
2191  case CK_FloatingComplexCast:
2192  case CK_IntegralRealToComplex:
2193  case CK_IntegralComplexCast:
2194  case CK_IntegralComplexToFloatingComplex:
2195  case CK_FloatingComplexToIntegralComplex:
2196  case CK_ConstructorConversion:
2197  case CK_ToUnion:
2198  llvm_unreachable("scalar cast to non-scalar value");
2199 
2200  case CK_LValueToRValue:
2201  assert(CGF.getContext().hasSameUnqualifiedType(E->getType(), DestTy));
2202  assert(E->isGLValue() && "lvalue-to-rvalue applied to r-value!");
2203  return Visit(const_cast<Expr*>(E));
2204 
2205  case CK_IntegralToPointer: {
2206  Value *Src = Visit(const_cast<Expr*>(E));
2207 
2208  // First, convert to the correct width so that we control the kind of
2209  // extension.
2210  auto DestLLVMTy = ConvertType(DestTy);
2211  llvm::Type *MiddleTy = CGF.CGM.getDataLayout().getIntPtrType(DestLLVMTy);
2212  bool InputSigned = E->getType()->isSignedIntegerOrEnumerationType();
2213  llvm::Value* IntResult =
2214  Builder.CreateIntCast(Src, MiddleTy, InputSigned, "conv");
2215 
2216  auto *IntToPtr = Builder.CreateIntToPtr(IntResult, DestLLVMTy);
2217 
2218  if (CGF.CGM.getCodeGenOpts().StrictVTablePointers) {
2219  // Going from integer to pointer that could be dynamic requires reloading
2220  // dynamic information from invariant.group.
2221  if (DestTy.mayBeDynamicClass())
2222  IntToPtr = Builder.CreateLaunderInvariantGroup(IntToPtr);
2223  }
2224  return IntToPtr;
2225  }
2226  case CK_PointerToIntegral: {
2227  assert(!DestTy->isBooleanType() && "bool should use PointerToBool");
2228  auto *PtrExpr = Visit(E);
2229 
2230  if (CGF.CGM.getCodeGenOpts().StrictVTablePointers) {
2231  const QualType SrcType = E->getType();
2232 
2233  // Casting to integer requires stripping dynamic information as it does
2234  // not carries it.
2235  if (SrcType.mayBeDynamicClass())
2236  PtrExpr = Builder.CreateStripInvariantGroup(PtrExpr);
2237  }
2238 
2239  return Builder.CreatePtrToInt(PtrExpr, ConvertType(DestTy));
2240  }
2241  case CK_ToVoid: {
2242  CGF.EmitIgnoredExpr(E);
2243  return nullptr;
2244  }
2245  case CK_VectorSplat: {
2246  llvm::Type *DstTy = ConvertType(DestTy);
2247  Value *Elt = Visit(const_cast<Expr*>(E));
2248  // Splat the element across to all elements
2249  unsigned NumElements = DstTy->getVectorNumElements();
2250  return Builder.CreateVectorSplat(NumElements, Elt, "splat");
2251  }
2252 
2253  case CK_FixedPointCast:
2254  return EmitScalarConversion(Visit(E), E->getType(), DestTy,
2255  CE->getExprLoc());
2256 
2257  case CK_FixedPointToBoolean:
2258  assert(E->getType()->isFixedPointType() &&
2259  "Expected src type to be fixed point type");
2260  assert(DestTy->isBooleanType() && "Expected dest type to be boolean type");
2261  return EmitScalarConversion(Visit(E), E->getType(), DestTy,
2262  CE->getExprLoc());
2263 
2264  case CK_FixedPointToIntegral:
2265  assert(E->getType()->isFixedPointType() &&
2266  "Expected src type to be fixed point type");
2267  assert(DestTy->isIntegerType() && "Expected dest type to be an integer");
2268  return EmitScalarConversion(Visit(E), E->getType(), DestTy,
2269  CE->getExprLoc());
2270 
2271  case CK_IntegralToFixedPoint:
2272  assert(E->getType()->isIntegerType() &&
2273  "Expected src type to be an integer");
2274  assert(DestTy->isFixedPointType() &&
2275  "Expected dest type to be fixed point type");
2276  return EmitScalarConversion(Visit(E), E->getType(), DestTy,
2277  CE->getExprLoc());
2278 
2279  case CK_IntegralCast: {
2280  ScalarConversionOpts Opts;
2281  if (auto *ICE = dyn_cast<ImplicitCastExpr>(CE)) {
2282  if (!ICE->isPartOfExplicitCast())
2283  Opts = ScalarConversionOpts(CGF.SanOpts);
2284  }
2285  return EmitScalarConversion(Visit(E), E->getType(), DestTy,
2286  CE->getExprLoc(), Opts);
2287  }
2288  case CK_IntegralToFloating:
2289  case CK_FloatingToIntegral:
2290  case CK_FloatingCast:
2291  return EmitScalarConversion(Visit(E), E->getType(), DestTy,
2292  CE->getExprLoc());
2293  case CK_BooleanToSignedIntegral: {
2294  ScalarConversionOpts Opts;
2295  Opts.TreatBooleanAsSigned = true;
2296  return EmitScalarConversion(Visit(E), E->getType(), DestTy,
2297  CE->getExprLoc(), Opts);
2298  }
2299  case CK_IntegralToBoolean:
2300  return EmitIntToBoolConversion(Visit(E));
2301  case CK_PointerToBoolean:
2302  return EmitPointerToBoolConversion(Visit(E), E->getType());
2303  case CK_FloatingToBoolean:
2304  return EmitFloatToBoolConversion(Visit(E));
2305  case CK_MemberPointerToBoolean: {
2306  llvm::Value *MemPtr = Visit(E);
2307  const MemberPointerType *MPT = E->getType()->getAs<MemberPointerType>();
2308  return CGF.CGM.getCXXABI().EmitMemberPointerIsNotNull(CGF, MemPtr, MPT);
2309  }
2310 
2311  case CK_FloatingComplexToReal:
2312  case CK_IntegralComplexToReal:
2313  return CGF.EmitComplexExpr(E, false, true).first;
2314 
2315  case CK_FloatingComplexToBoolean:
2316  case CK_IntegralComplexToBoolean: {
2318 
2319  // TODO: kill this function off, inline appropriate case here
2320  return EmitComplexToScalarConversion(V, E->getType(), DestTy,
2321  CE->getExprLoc());
2322  }
2323 
2324  case CK_ZeroToOCLOpaqueType: {
2325  assert((DestTy->isEventT() || DestTy->isQueueT() ||
2326  DestTy->isOCLIntelSubgroupAVCType()) &&
2327  "CK_ZeroToOCLEvent cast on non-event type");
2328  return llvm::Constant::getNullValue(ConvertType(DestTy));
2329  }
2330 
2331  case CK_IntToOCLSampler:
2332  return CGF.CGM.createOpenCLIntToSamplerConversion(E, CGF);
2333 
2334  } // end of switch
2335 
2336  llvm_unreachable("unknown scalar cast");
2337 }
2338 
2339 Value *ScalarExprEmitter::VisitStmtExpr(const StmtExpr *E) {
2341  Address RetAlloca = CGF.EmitCompoundStmt(*E->getSubStmt(),
2342  !E->getType()->isVoidType());
2343  if (!RetAlloca.isValid())
2344  return nullptr;
2345  return CGF.EmitLoadOfScalar(CGF.MakeAddrLValue(RetAlloca, E->getType()),
2346  E->getExprLoc());
2347 }
2348 
2349 Value *ScalarExprEmitter::VisitExprWithCleanups(ExprWithCleanups *E) {
2350  CGF.enterFullExpression(E);
2352  Value *V = Visit(E->getSubExpr());
2353  // Defend against dominance problems caused by jumps out of expression
2354  // evaluation through the shared cleanup block.
2355  Scope.ForceCleanup({&V});
2356  return V;
2357 }
2358 
2359 //===----------------------------------------------------------------------===//
2360 // Unary Operators
2361 //===----------------------------------------------------------------------===//
2362 
2363 static BinOpInfo createBinOpInfoFromIncDec(const UnaryOperator *E,
2364  llvm::Value *InVal, bool IsInc) {
2365  BinOpInfo BinOp;
2366  BinOp.LHS = InVal;
2367  BinOp.RHS = llvm::ConstantInt::get(InVal->getType(), 1, false);
2368  BinOp.Ty = E->getType();
2369  BinOp.Opcode = IsInc ? BO_Add : BO_Sub;
2370  // FIXME: once UnaryOperator carries FPFeatures, copy it here.
2371  BinOp.E = E;
2372  return BinOp;
2373 }
2374 
2375 llvm::Value *ScalarExprEmitter::EmitIncDecConsiderOverflowBehavior(
2376  const UnaryOperator *E, llvm::Value *InVal, bool IsInc) {
2377  llvm::Value *Amount =
2378  llvm::ConstantInt::get(InVal->getType(), IsInc ? 1 : -1, true);
2379  StringRef Name = IsInc ? "inc" : "dec";
2380  switch (CGF.getLangOpts().getSignedOverflowBehavior()) {
2382  return Builder.CreateAdd(InVal, Amount, Name);
2384  if (!CGF.SanOpts.has(SanitizerKind::SignedIntegerOverflow))
2385  return Builder.CreateNSWAdd(InVal, Amount, Name);
2386  LLVM_FALLTHROUGH;
2388  if (!E->canOverflow())
2389  return Builder.CreateNSWAdd(InVal, Amount, Name);
2390  return EmitOverflowCheckedBinOp(createBinOpInfoFromIncDec(E, InVal, IsInc));
2391  }
2392  llvm_unreachable("Unknown SignedOverflowBehaviorTy");
2393 }
2394 
2395 llvm::Value *
2396 ScalarExprEmitter::EmitScalarPrePostIncDec(const UnaryOperator *E, LValue LV,
2397  bool isInc, bool isPre) {
2398 
2399  QualType type = E->getSubExpr()->getType();
2400  llvm::PHINode *atomicPHI = nullptr;
2401  llvm::Value *value;
2402  llvm::Value *input;
2403 
2404  int amount = (isInc ? 1 : -1);
2405  bool isSubtraction = !isInc;
2406 
2407  if (const AtomicType *atomicTy = type->getAs<AtomicType>()) {
2408  type = atomicTy->getValueType();
2409  if (isInc && type->isBooleanType()) {
2410  llvm::Value *True = CGF.EmitToMemory(Builder.getTrue(), type);
2411  if (isPre) {
2412  Builder.CreateStore(True, LV.getAddress(), LV.isVolatileQualified())
2413  ->setAtomic(llvm::AtomicOrdering::SequentiallyConsistent);
2414  return Builder.getTrue();
2415  }
2416  // For atomic bool increment, we just store true and return it for
2417  // preincrement, do an atomic swap with true for postincrement
2418  return Builder.CreateAtomicRMW(
2419  llvm::AtomicRMWInst::Xchg, LV.getPointer(), True,
2420  llvm::AtomicOrdering::SequentiallyConsistent);
2421  }
2422  // Special case for atomic increment / decrement on integers, emit
2423  // atomicrmw instructions. We skip this if we want to be doing overflow
2424  // checking, and fall into the slow path with the atomic cmpxchg loop.
2425  if (!type->isBooleanType() && type->isIntegerType() &&
2426  !(type->isUnsignedIntegerType() &&
2427  CGF.SanOpts.has(SanitizerKind::UnsignedIntegerOverflow)) &&
2428  CGF.getLangOpts().getSignedOverflowBehavior() !=
2430  llvm::AtomicRMWInst::BinOp aop = isInc ? llvm::AtomicRMWInst::Add :
2431  llvm::AtomicRMWInst::Sub;
2432  llvm::Instruction::BinaryOps op = isInc ? llvm::Instruction::Add :
2433  llvm::Instruction::Sub;
2434  llvm::Value *amt = CGF.EmitToMemory(
2435  llvm::ConstantInt::get(ConvertType(type), 1, true), type);
2436  llvm::Value *old = Builder.CreateAtomicRMW(aop,
2437  LV.getPointer(), amt, llvm::AtomicOrdering::SequentiallyConsistent);
2438  return isPre ? Builder.CreateBinOp(op, old, amt) : old;
2439  }
2440  value = EmitLoadOfLValue(LV, E->getExprLoc());
2441  input = value;
2442  // For every other atomic operation, we need to emit a load-op-cmpxchg loop
2443  llvm::BasicBlock *startBB = Builder.GetInsertBlock();
2444  llvm::BasicBlock *opBB = CGF.createBasicBlock("atomic_op", CGF.CurFn);
2445  value = CGF.EmitToMemory(value, type);
2446  Builder.CreateBr(opBB);
2447  Builder.SetInsertPoint(opBB);
2448  atomicPHI = Builder.CreatePHI(value->getType(), 2);
2449  atomicPHI->addIncoming(value, startBB);
2450  value = atomicPHI;
2451  } else {
2452  value = EmitLoadOfLValue(LV, E->getExprLoc());
2453  input = value;
2454  }
2455 
2456  // Special case of integer increment that we have to check first: bool++.
2457  // Due to promotion rules, we get:
2458  // bool++ -> bool = bool + 1
2459  // -> bool = (int)bool + 1
2460  // -> bool = ((int)bool + 1 != 0)
2461  // An interesting aspect of this is that increment is always true.
2462  // Decrement does not have this property.
2463  if (isInc && type->isBooleanType()) {
2464  value = Builder.getTrue();
2465 
2466  // Most common case by far: integer increment.
2467  } else if (type->isIntegerType()) {
2468  // Note that signed integer inc/dec with width less than int can't
2469  // overflow because of promotion rules; we're just eliding a few steps here.
2470  if (E->canOverflow() && type->isSignedIntegerOrEnumerationType()) {
2471  value = EmitIncDecConsiderOverflowBehavior(E, value, isInc);
2472  } else if (E->canOverflow() && type->isUnsignedIntegerType() &&
2473  CGF.SanOpts.has(SanitizerKind::UnsignedIntegerOverflow)) {
2474  value =
2475  EmitOverflowCheckedBinOp(createBinOpInfoFromIncDec(E, value, isInc));
2476  } else {
2477  llvm::Value *amt = llvm::ConstantInt::get(value->getType(), amount, true);
2478  value = Builder.CreateAdd(value, amt, isInc ? "inc" : "dec");
2479  }
2480 
2481  // Next most common: pointer increment.
2482  } else if (const PointerType *ptr = type->getAs<PointerType>()) {
2483  QualType type = ptr->getPointeeType();
2484 
2485  // VLA types don't have constant size.
2486  if (const VariableArrayType *vla
2487  = CGF.getContext().getAsVariableArrayType(type)) {
2488  llvm::Value *numElts = CGF.getVLASize(vla).NumElts;
2489  if (!isInc) numElts = Builder.CreateNSWNeg(numElts, "vla.negsize");
2491  value = Builder.CreateGEP(value, numElts, "vla.inc");
2492  else
2493  value = CGF.EmitCheckedInBoundsGEP(
2494  value, numElts, /*SignedIndices=*/false, isSubtraction,
2495  E->getExprLoc(), "vla.inc");
2496 
2497  // Arithmetic on function pointers (!) is just +-1.
2498  } else if (type->isFunctionType()) {
2499  llvm::Value *amt = Builder.getInt32(amount);
2500 
2501  value = CGF.EmitCastToVoidPtr(value);
2503  value = Builder.CreateGEP(value, amt, "incdec.funcptr");
2504  else
2505  value = CGF.EmitCheckedInBoundsGEP(value, amt, /*SignedIndices=*/false,
2506  isSubtraction, E->getExprLoc(),
2507  "incdec.funcptr");
2508  value = Builder.CreateBitCast(value, input->getType());
2509 
2510  // For everything else, we can just do a simple increment.
2511  } else {
2512  llvm::Value *amt = Builder.getInt32(amount);
2514  value = Builder.CreateGEP(value, amt, "incdec.ptr");
2515  else
2516  value = CGF.EmitCheckedInBoundsGEP(value, amt, /*SignedIndices=*/false,
2517  isSubtraction, E->getExprLoc(),
2518  "incdec.ptr");
2519  }
2520 
2521  // Vector increment/decrement.
2522  } else if (type->isVectorType()) {
2523  if (type->hasIntegerRepresentation()) {
2524  llvm::Value *amt = llvm::ConstantInt::get(value->getType(), amount);
2525 
2526  value = Builder.CreateAdd(value, amt, isInc ? "inc" : "dec");
2527  } else {
2528  value = Builder.CreateFAdd(
2529  value,
2530  llvm::ConstantFP::get(value->getType(), amount),
2531  isInc ? "inc" : "dec");
2532  }
2533 
2534  // Floating point.
2535  } else if (type->isRealFloatingType()) {
2536  // Add the inc/dec to the real part.
2537  llvm::Value *amt;
2538 
2539  if (type->isHalfType() && !CGF.getContext().getLangOpts().NativeHalfType) {
2540  // Another special case: half FP increment should be done via float
2542  value = Builder.CreateCall(
2543  CGF.CGM.getIntrinsic(llvm::Intrinsic::convert_from_fp16,
2544  CGF.CGM.FloatTy),
2545  input, "incdec.conv");
2546  } else {
2547  value = Builder.CreateFPExt(input, CGF.CGM.FloatTy, "incdec.conv");
2548  }
2549  }
2550 
2551  if (value->getType()->isFloatTy())
2552  amt = llvm::ConstantFP::get(VMContext,
2553  llvm::APFloat(static_cast<float>(amount)));
2554  else if (value->getType()->isDoubleTy())
2555  amt = llvm::ConstantFP::get(VMContext,
2556  llvm::APFloat(static_cast<double>(amount)));
2557  else {
2558  // Remaining types are Half, LongDouble or __float128. Convert from float.
2559  llvm::APFloat F(static_cast<float>(amount));
2560  bool ignored;
2561  const llvm::fltSemantics *FS;
2562  // Don't use getFloatTypeSemantics because Half isn't
2563  // necessarily represented using the "half" LLVM type.
2564  if (value->getType()->isFP128Ty())
2565  FS = &CGF.getTarget().getFloat128Format();
2566  else if (value->getType()->isHalfTy())
2567  FS = &CGF.getTarget().getHalfFormat();
2568  else
2569  FS = &CGF.getTarget().getLongDoubleFormat();
2570  F.convert(*FS, llvm::APFloat::rmTowardZero, &ignored);
2571  amt = llvm::ConstantFP::get(VMContext, F);
2572  }
2573  value = Builder.CreateFAdd(value, amt, isInc ? "inc" : "dec");
2574 
2575  if (type->isHalfType() && !CGF.getContext().getLangOpts().NativeHalfType) {
2577  value = Builder.CreateCall(
2578  CGF.CGM.getIntrinsic(llvm::Intrinsic::convert_to_fp16,
2579  CGF.CGM.FloatTy),
2580  value, "incdec.conv");
2581  } else {
2582  value = Builder.CreateFPTrunc(value, input->getType(), "incdec.conv");
2583  }
2584  }
2585 
2586  // Objective-C pointer types.
2587  } else {
2588  const ObjCObjectPointerType *OPT = type->castAs<ObjCObjectPointerType>();
2589  value = CGF.EmitCastToVoidPtr(value);
2590 
2592  if (!isInc) size = -size;
2593  llvm::Value *sizeValue =
2594  llvm::ConstantInt::get(CGF.SizeTy, size.getQuantity());
2595 
2597  value = Builder.CreateGEP(value, sizeValue, "incdec.objptr");
2598  else
2599  value = CGF.EmitCheckedInBoundsGEP(value, sizeValue,
2600  /*SignedIndices=*/false, isSubtraction,
2601  E->getExprLoc(), "incdec.objptr");
2602  value = Builder.CreateBitCast(value, input->getType());
2603  }
2604 
2605  if (atomicPHI) {
2606  llvm::BasicBlock *curBlock = Builder.GetInsertBlock();
2607  llvm::BasicBlock *contBB = CGF.createBasicBlock("atomic_cont", CGF.CurFn);
2608  auto Pair = CGF.EmitAtomicCompareExchange(
2609  LV, RValue::get(atomicPHI), RValue::get(value), E->getExprLoc());
2610  llvm::Value *old = CGF.EmitToMemory(Pair.first.getScalarVal(), type);
2611  llvm::Value *success = Pair.second;
2612  atomicPHI->addIncoming(old, curBlock);
2613  Builder.CreateCondBr(success, contBB, atomicPHI->getParent());
2614  Builder.SetInsertPoint(contBB);
2615  return isPre ? value : input;
2616  }
2617 
2618  // Store the updated result through the lvalue.
2619  if (LV.isBitField())
2620  CGF.EmitStoreThroughBitfieldLValue(RValue::get(value), LV, &value);
2621  else
2622  CGF.EmitStoreThroughLValue(RValue::get(value), LV);
2623 
2624  // If this is a postinc, return the value read from memory, otherwise use the
2625  // updated value.
2626  return isPre ? value : input;
2627 }
2628 
2629 
2630 
2631 Value *ScalarExprEmitter::VisitUnaryMinus(const UnaryOperator *E) {
2632  TestAndClearIgnoreResultAssign();
2633  // Emit unary minus with EmitSub so we handle overflow cases etc.
2634  BinOpInfo BinOp;
2635  BinOp.RHS = Visit(E->getSubExpr());
2636 
2637  if (BinOp.RHS->getType()->isFPOrFPVectorTy())
2638  BinOp.LHS = llvm::ConstantFP::getZeroValueForNegation(BinOp.RHS->getType());
2639  else
2640  BinOp.LHS = llvm::Constant::getNullValue(BinOp.RHS->getType());
2641  BinOp.Ty = E->getType();
2642  BinOp.Opcode = BO_Sub;
2643  // FIXME: once UnaryOperator carries FPFeatures, copy it here.
2644  BinOp.E = E;
2645  return EmitSub(BinOp);
2646 }
2647 
2648 Value *ScalarExprEmitter::VisitUnaryNot(const UnaryOperator *E) {
2649  TestAndClearIgnoreResultAssign();
2650  Value *Op = Visit(E->getSubExpr());
2651  return Builder.CreateNot(Op, "neg");
2652 }
2653 
2654 Value *ScalarExprEmitter::VisitUnaryLNot(const UnaryOperator *E) {
2655  // Perform vector logical not on comparison with zero vector.
2656  if (E->getType()->isExtVectorType()) {
2657  Value *Oper = Visit(E->getSubExpr());
2658  Value *Zero = llvm::Constant::getNullValue(Oper->getType());
2659  Value *Result;
2660  if (Oper->getType()->isFPOrFPVectorTy())
2661  Result = Builder.CreateFCmp(llvm::CmpInst::FCMP_OEQ, Oper, Zero, "cmp");
2662  else
2663  Result = Builder.CreateICmp(llvm::CmpInst::ICMP_EQ, Oper, Zero, "cmp");
2664  return Builder.CreateSExt(Result, ConvertType(E->getType()), "sext");
2665  }
2666 
2667  // Compare operand to zero.
2668  Value *BoolVal = CGF.EvaluateExprAsBool(E->getSubExpr());
2669 
2670  // Invert value.
2671  // TODO: Could dynamically modify easy computations here. For example, if
2672  // the operand is an icmp ne, turn into icmp eq.
2673  BoolVal = Builder.CreateNot(BoolVal, "lnot");
2674 
2675  // ZExt result to the expr type.
2676  return Builder.CreateZExt(BoolVal, ConvertType(E->getType()), "lnot.ext");
2677 }
2678 
2679 Value *ScalarExprEmitter::VisitOffsetOfExpr(OffsetOfExpr *E) {
2680  // Try folding the offsetof to a constant.
2681  Expr::EvalResult EVResult;
2682  if (E->EvaluateAsInt(EVResult, CGF.getContext())) {
2683  llvm::APSInt Value = EVResult.Val.getInt();
2684  return Builder.getInt(Value);
2685  }
2686 
2687  // Loop over the components of the offsetof to compute the value.
2688  unsigned n = E->getNumComponents();
2689  llvm::Type* ResultType = ConvertType(E->getType());
2690  llvm::Value* Result = llvm::Constant::getNullValue(ResultType);
2691  QualType CurrentType = E->getTypeSourceInfo()->getType();
2692  for (unsigned i = 0; i != n; ++i) {
2693  OffsetOfNode ON = E->getComponent(i);
2694  llvm::Value *Offset = nullptr;
2695  switch (ON.getKind()) {
2696  case OffsetOfNode::Array: {
2697  // Compute the index
2698  Expr *IdxExpr = E->getIndexExpr(ON.getArrayExprIndex());
2699  llvm::Value* Idx = CGF.EmitScalarExpr(IdxExpr);
2700  bool IdxSigned = IdxExpr->getType()->isSignedIntegerOrEnumerationType();
2701  Idx = Builder.CreateIntCast(Idx, ResultType, IdxSigned, "conv");
2702 
2703  // Save the element type
2704  CurrentType =
2705  CGF.getContext().getAsArrayType(CurrentType)->getElementType();
2706 
2707  // Compute the element size
2708  llvm::Value* ElemSize = llvm::ConstantInt::get(ResultType,
2709  CGF.getContext().getTypeSizeInChars(CurrentType).getQuantity());
2710 
2711  // Multiply out to compute the result
2712  Offset = Builder.CreateMul(Idx, ElemSize);
2713  break;
2714  }
2715 
2716  case OffsetOfNode::Field: {
2717  FieldDecl *MemberDecl = ON.getField();
2718  RecordDecl *RD = CurrentType->getAs<RecordType>()->getDecl();
2719  const ASTRecordLayout &RL = CGF.getContext().getASTRecordLayout(RD);
2720 
2721  // Compute the index of the field in its parent.
2722  unsigned i = 0;
2723  // FIXME: It would be nice if we didn't have to loop here!
2724  for (RecordDecl::field_iterator Field = RD->field_begin(),
2725  FieldEnd = RD->field_end();
2726  Field != FieldEnd; ++Field, ++i) {
2727  if (*Field == MemberDecl)
2728  break;
2729  }
2730  assert(i < RL.getFieldCount() && "offsetof field in wrong type");
2731 
2732  // Compute the offset to the field
2733  int64_t OffsetInt = RL.getFieldOffset(i) /
2734  CGF.getContext().getCharWidth();
2735  Offset = llvm::ConstantInt::get(ResultType, OffsetInt);
2736 
2737  // Save the element type.
2738  CurrentType = MemberDecl->getType();
2739  break;
2740  }
2741 
2743  llvm_unreachable("dependent __builtin_offsetof");
2744 
2745  case OffsetOfNode::Base: {
2746  if (ON.getBase()->isVirtual()) {
2747  CGF.ErrorUnsupported(E, "virtual base in offsetof");
2748  continue;
2749  }
2750 
2751  RecordDecl *RD = CurrentType->getAs<RecordType>()->getDecl();
2752  const ASTRecordLayout &RL = CGF.getContext().getASTRecordLayout(RD);
2753 
2754  // Save the element type.
2755  CurrentType = ON.getBase()->getType();
2756 
2757  // Compute the offset to the base.
2758  const RecordType *BaseRT = CurrentType->getAs<RecordType>();
2759  CXXRecordDecl *BaseRD = cast<CXXRecordDecl>(BaseRT->getDecl());
2760  CharUnits OffsetInt = RL.getBaseClassOffset(BaseRD);
2761  Offset = llvm::ConstantInt::get(ResultType, OffsetInt.getQuantity());
2762  break;
2763  }
2764  }
2765  Result = Builder.CreateAdd(Result, Offset);
2766  }
2767  return Result;
2768 }
2769 
2770 /// VisitUnaryExprOrTypeTraitExpr - Return the size or alignment of the type of
2771 /// argument of the sizeof expression as an integer.
2772 Value *
2773 ScalarExprEmitter::VisitUnaryExprOrTypeTraitExpr(
2774  const UnaryExprOrTypeTraitExpr *E) {
2775  QualType TypeToSize = E->getTypeOfArgument();
2776  if (E->getKind() == UETT_SizeOf) {
2777  if (const VariableArrayType *VAT =
2778  CGF.getContext().getAsVariableArrayType(TypeToSize)) {
2779  if (E->isArgumentType()) {
2780  // sizeof(type) - make sure to emit the VLA size.
2781  CGF.EmitVariablyModifiedType(TypeToSize);
2782  } else {
2783  // C99 6.5.3.4p2: If the argument is an expression of type
2784  // VLA, it is evaluated.
2785  CGF.EmitIgnoredExpr(E->getArgumentExpr());
2786  }
2787 
2788  auto VlaSize = CGF.getVLASize(VAT);
2789  llvm::Value *size = VlaSize.NumElts;
2790 
2791  // Scale the number of non-VLA elements by the non-VLA element size.
2792  CharUnits eltSize = CGF.getContext().getTypeSizeInChars(VlaSize.Type);
2793  if (!eltSize.isOne())
2794  size = CGF.Builder.CreateNUWMul(CGF.CGM.getSize(eltSize), size);
2795 
2796  return size;
2797  }
2798  } else if (E->getKind() == UETT_OpenMPRequiredSimdAlign) {
2799  auto Alignment =
2800  CGF.getContext()
2803  .getQuantity();
2804  return llvm::ConstantInt::get(CGF.SizeTy, Alignment);
2805  }
2806 
2807  // If this isn't sizeof(vla), the result must be constant; use the constant
2808  // folding logic so we don't have to duplicate it here.
2809  return Builder.getInt(E->EvaluateKnownConstInt(CGF.getContext()));
2810 }
2811 
2812 Value *ScalarExprEmitter::VisitUnaryReal(const UnaryOperator *E) {
2813  Expr *Op = E->getSubExpr();
2814  if (Op->getType()->isAnyComplexType()) {
2815  // If it's an l-value, load through the appropriate subobject l-value.
2816  // Note that we have to ask E because Op might be an l-value that
2817  // this won't work for, e.g. an Obj-C property.
2818  if (E->isGLValue())
2819  return CGF.EmitLoadOfLValue(CGF.EmitLValue(E),
2820  E->getExprLoc()).getScalarVal();
2821 
2822  // Otherwise, calculate and project.
2823  return CGF.EmitComplexExpr(Op, false, true).first;
2824  }
2825 
2826  return Visit(Op);
2827 }
2828 
2829 Value *ScalarExprEmitter::VisitUnaryImag(const UnaryOperator *E) {
2830  Expr *Op = E->getSubExpr();
2831  if (Op->getType()->isAnyComplexType()) {
2832  // If it's an l-value, load through the appropriate subobject l-value.
2833  // Note that we have to ask E because Op might be an l-value that
2834  // this won't work for, e.g. an Obj-C property.
2835  if (Op->isGLValue())
2836  return CGF.EmitLoadOfLValue(CGF.EmitLValue(E),
2837  E->getExprLoc()).getScalarVal();
2838 
2839  // Otherwise, calculate and project.
2840  return CGF.EmitComplexExpr(Op, true, false).second;
2841  }
2842 
2843  // __imag on a scalar returns zero. Emit the subexpr to ensure side
2844  // effects are evaluated, but not the actual value.
2845  if (Op->isGLValue())
2846  CGF.EmitLValue(Op);
2847  else
2848  CGF.EmitScalarExpr(Op, true);
2849  return llvm::Constant::getNullValue(ConvertType(E->getType()));
2850 }
2851 
2852 //===----------------------------------------------------------------------===//
2853 // Binary Operators
2854 //===----------------------------------------------------------------------===//
2855 
2856 BinOpInfo ScalarExprEmitter::EmitBinOps(const BinaryOperator *E) {
2857  TestAndClearIgnoreResultAssign();
2858  BinOpInfo Result;
2859  Result.LHS = Visit(E->getLHS());
2860  Result.RHS = Visit(E->getRHS());
2861  Result.Ty = E->getType();
2862  Result.Opcode = E->getOpcode();
2863  Result.FPFeatures = E->getFPFeatures();
2864  Result.E = E;
2865  return Result;
2866 }
2867 
2868 LValue ScalarExprEmitter::EmitCompoundAssignLValue(
2869  const CompoundAssignOperator *E,
2870  Value *(ScalarExprEmitter::*Func)(const BinOpInfo &),
2871  Value *&Result) {
2872  QualType LHSTy = E->getLHS()->getType();
2873  BinOpInfo OpInfo;
2874 
2876  return CGF.EmitScalarCompoundAssignWithComplex(E, Result);
2877 
2878  // Emit the RHS first. __block variables need to have the rhs evaluated
2879  // first, plus this should improve codegen a little.
2880  OpInfo.RHS = Visit(E->getRHS());
2881  OpInfo.Ty = E->getComputationResultType();
2882  OpInfo.Opcode = E->getOpcode();
2883  OpInfo.FPFeatures = E->getFPFeatures();
2884  OpInfo.E = E;
2885  // Load/convert the LHS.
2886  LValue LHSLV = EmitCheckedLValue(E->getLHS(), CodeGenFunction::TCK_Store);
2887 
2888  llvm::PHINode *atomicPHI = nullptr;
2889  if (const AtomicType *atomicTy = LHSTy->getAs<AtomicType>()) {
2890  QualType type = atomicTy->getValueType();
2891  if (!type->isBooleanType() && type->isIntegerType() &&
2892  !(type->isUnsignedIntegerType() &&
2893  CGF.SanOpts.has(SanitizerKind::UnsignedIntegerOverflow)) &&
2894  CGF.getLangOpts().getSignedOverflowBehavior() !=
2896  llvm::AtomicRMWInst::BinOp aop = llvm::AtomicRMWInst::BAD_BINOP;
2897  switch (OpInfo.Opcode) {
2898  // We don't have atomicrmw operands for *, %, /, <<, >>
2899  case BO_MulAssign: case BO_DivAssign:
2900  case BO_RemAssign:
2901  case BO_ShlAssign:
2902  case BO_ShrAssign:
2903  break;
2904  case BO_AddAssign:
2905  aop = llvm::AtomicRMWInst::Add;
2906  break;
2907  case BO_SubAssign:
2908  aop = llvm::AtomicRMWInst::Sub;
2909  break;
2910  case BO_AndAssign:
2912  break;
2913  case BO_XorAssign:
2914  aop = llvm::AtomicRMWInst::Xor;
2915  break;
2916  case BO_OrAssign:
2917  aop = llvm::AtomicRMWInst::Or;
2918  break;
2919  default:
2920  llvm_unreachable("Invalid compound assignment type");
2921  }
2922  if (aop != llvm::AtomicRMWInst::BAD_BINOP) {
2923  llvm::Value *amt = CGF.EmitToMemory(
2924  EmitScalarConversion(OpInfo.RHS, E->getRHS()->getType(), LHSTy,
2925  E->getExprLoc()),
2926  LHSTy);
2927  Builder.CreateAtomicRMW(aop, LHSLV.getPointer(), amt,
2928  llvm::AtomicOrdering::SequentiallyConsistent);
2929  return LHSLV;
2930  }
2931  }
2932  // FIXME: For floating point types, we should be saving and restoring the
2933  // floating point environment in the loop.
2934  llvm::BasicBlock *startBB = Builder.GetInsertBlock();
2935  llvm::BasicBlock *opBB = CGF.createBasicBlock("atomic_op", CGF.CurFn);
2936  OpInfo.LHS = EmitLoadOfLValue(LHSLV, E->getExprLoc());
2937  OpInfo.LHS = CGF.EmitToMemory(OpInfo.LHS, type);
2938  Builder.CreateBr(opBB);
2939  Builder.SetInsertPoint(opBB);
2940  atomicPHI = Builder.CreatePHI(OpInfo.LHS->getType(), 2);
2941  atomicPHI->addIncoming(OpInfo.LHS, startBB);
2942  OpInfo.LHS = atomicPHI;
2943  }
2944  else
2945  OpInfo.LHS = EmitLoadOfLValue(LHSLV, E->getExprLoc());
2946 
2947  SourceLocation Loc = E->getExprLoc();
2948  OpInfo.LHS =
2949  EmitScalarConversion(OpInfo.LHS, LHSTy, E->getComputationLHSType(), Loc);
2950 
2951  // Expand the binary operator.
2952  Result = (this->*Func)(OpInfo);
2953 
2954  // Convert the result back to the LHS type,
2955  // potentially with Implicit Conversion sanitizer check.
2956  Result = EmitScalarConversion(Result, E->getComputationResultType(), LHSTy,
2957  Loc, ScalarConversionOpts(CGF.SanOpts));
2958 
2959  if (atomicPHI) {
2960  llvm::BasicBlock *curBlock = Builder.GetInsertBlock();
2961  llvm::BasicBlock *contBB = CGF.createBasicBlock("atomic_cont", CGF.CurFn);
2962  auto Pair = CGF.EmitAtomicCompareExchange(
2963  LHSLV, RValue::get(atomicPHI), RValue::get(Result), E->getExprLoc());
2964  llvm::Value *old = CGF.EmitToMemory(Pair.first.getScalarVal(), LHSTy);
2965  llvm::Value *success = Pair.second;
2966  atomicPHI->addIncoming(old, curBlock);
2967  Builder.CreateCondBr(success, contBB, atomicPHI->getParent());
2968  Builder.SetInsertPoint(contBB);
2969  return LHSLV;
2970  }
2971 
2972  // Store the result value into the LHS lvalue. Bit-fields are handled
2973  // specially because the result is altered by the store, i.e., [C99 6.5.16p1]
2974  // 'An assignment expression has the value of the left operand after the
2975  // assignment...'.
2976  if (LHSLV.isBitField())
2977  CGF.EmitStoreThroughBitfieldLValue(RValue::get(Result), LHSLV, &Result);
2978  else
2979  CGF.EmitStoreThroughLValue(RValue::get(Result), LHSLV);
2980 
2981  return LHSLV;
2982 }
2983 
2984 Value *ScalarExprEmitter::EmitCompoundAssign(const CompoundAssignOperator *E,
2985  Value *(ScalarExprEmitter::*Func)(const BinOpInfo &)) {
2986  bool Ignore = TestAndClearIgnoreResultAssign();
2987  Value *RHS = nullptr;
2988  LValue LHS = EmitCompoundAssignLValue(E, Func, RHS);
2989 
2990  // If the result is clearly ignored, return now.
2991  if (Ignore)
2992  return nullptr;
2993 
2994  // The result of an assignment in C is the assigned r-value.
2995  if (!CGF.getLangOpts().CPlusPlus)
2996  return RHS;
2997 
2998  // If the lvalue is non-volatile, return the computed value of the assignment.
2999  if (!LHS.isVolatileQualified())
3000  return RHS;
3001 
3002  // Otherwise, reload the value.
3003  return EmitLoadOfLValue(LHS, E->getExprLoc());
3004 }
3005 
3006 void ScalarExprEmitter::EmitUndefinedBehaviorIntegerDivAndRemCheck(
3007  const BinOpInfo &Ops, llvm::Value *Zero, bool isDiv) {
3009 
3010  if (CGF.SanOpts.has(SanitizerKind::IntegerDivideByZero)) {
3011  Checks.push_back(std::make_pair(Builder.CreateICmpNE(Ops.RHS, Zero),
3012  SanitizerKind::IntegerDivideByZero));
3013  }
3014 
3015  const auto *BO = cast<BinaryOperator>(Ops.E);
3016  if (CGF.SanOpts.has(SanitizerKind::SignedIntegerOverflow) &&
3017  Ops.Ty->hasSignedIntegerRepresentation() &&
3018  !IsWidenedIntegerOp(CGF.getContext(), BO->getLHS()) &&
3019  Ops.mayHaveIntegerOverflow()) {
3020  llvm::IntegerType *Ty = cast<llvm::IntegerType>(Zero->getType());
3021 
3022  llvm::Value *IntMin =
3023  Builder.getInt(llvm::APInt::getSignedMinValue(Ty->getBitWidth()));
3024  llvm::Value *NegOne = llvm::ConstantInt::get(Ty, -1ULL);
3025 
3026  llvm::Value *LHSCmp = Builder.CreateICmpNE(Ops.LHS, IntMin);
3027  llvm::Value *RHSCmp = Builder.CreateICmpNE(Ops.RHS, NegOne);
3028  llvm::Value *NotOverflow = Builder.CreateOr(LHSCmp, RHSCmp, "or");
3029  Checks.push_back(
3030  std::make_pair(NotOverflow, SanitizerKind::SignedIntegerOverflow));
3031  }
3032 
3033  if (Checks.size() > 0)
3034  EmitBinOpCheck(Checks, Ops);
3035 }
3036 
3037 Value *ScalarExprEmitter::EmitDiv(const BinOpInfo &Ops) {
3038  {
3039  CodeGenFunction::SanitizerScope SanScope(&CGF);
3040  if ((CGF.SanOpts.has(SanitizerKind::IntegerDivideByZero) ||
3041  CGF.SanOpts.has(SanitizerKind::SignedIntegerOverflow)) &&
3042  Ops.Ty->isIntegerType() &&
3043  (Ops.mayHaveIntegerDivisionByZero() || Ops.mayHaveIntegerOverflow())) {
3044  llvm::Value *Zero = llvm::Constant::getNullValue(ConvertType(Ops.Ty));
3045  EmitUndefinedBehaviorIntegerDivAndRemCheck(Ops, Zero, true);
3046  } else if (CGF.SanOpts.has(SanitizerKind::FloatDivideByZero) &&
3047  Ops.Ty->isRealFloatingType() &&
3048  Ops.mayHaveFloatDivisionByZero()) {
3049  llvm::Value *Zero = llvm::Constant::getNullValue(ConvertType(Ops.Ty));
3050  llvm::Value *NonZero = Builder.CreateFCmpUNE(Ops.RHS, Zero);
3051  EmitBinOpCheck(std::make_pair(NonZero, SanitizerKind::FloatDivideByZero),
3052  Ops);
3053  }
3054  }
3055 
3056  if (Ops.LHS->getType()->isFPOrFPVectorTy()) {
3057  llvm::Value *Val = Builder.CreateFDiv(Ops.LHS, Ops.RHS, "div");
3058  if (CGF.getLangOpts().OpenCL &&
3059  !CGF.CGM.getCodeGenOpts().CorrectlyRoundedDivSqrt) {
3060  // OpenCL v1.1 s7.4: minimum accuracy of single precision / is 2.5ulp
3061  // OpenCL v1.2 s5.6.4.2: The -cl-fp32-correctly-rounded-divide-sqrt
3062  // build option allows an application to specify that single precision
3063  // floating-point divide (x/y and 1/x) and sqrt used in the program
3064  // source are correctly rounded.
3065  llvm::Type *ValTy = Val->getType();
3066  if (ValTy->isFloatTy() ||
3067  (isa<llvm::VectorType>(ValTy) &&
3068  cast<llvm::VectorType>(ValTy)->getElementType()->isFloatTy()))
3069  CGF.SetFPAccuracy(Val, 2.5);
3070  }
3071  return Val;
3072  }
3073  else if (Ops.Ty->hasUnsignedIntegerRepresentation())
3074  return Builder.CreateUDiv(Ops.LHS, Ops.RHS, "div");
3075  else
3076  return Builder.CreateSDiv(Ops.LHS, Ops.RHS, "div");
3077 }
3078 
3079 Value *ScalarExprEmitter::EmitRem(const BinOpInfo &Ops) {
3080  // Rem in C can't be a floating point type: C99 6.5.5p2.
3081  if ((CGF.SanOpts.has(SanitizerKind::IntegerDivideByZero) ||
3082  CGF.SanOpts.has(SanitizerKind::SignedIntegerOverflow)) &&
3083  Ops.Ty->isIntegerType() &&
3084  (Ops.mayHaveIntegerDivisionByZero() || Ops.mayHaveIntegerOverflow())) {
3085  CodeGenFunction::SanitizerScope SanScope(&CGF);
3086  llvm::Value *Zero = llvm::Constant::getNullValue(ConvertType(Ops.Ty));
3087  EmitUndefinedBehaviorIntegerDivAndRemCheck(Ops, Zero, false);
3088  }
3089 
3090  if (Ops.Ty->hasUnsignedIntegerRepresentation())
3091  return Builder.CreateURem(Ops.LHS, Ops.RHS, "rem");
3092  else
3093  return Builder.CreateSRem(Ops.LHS, Ops.RHS, "rem");
3094 }
3095 
3096 Value *ScalarExprEmitter::EmitOverflowCheckedBinOp(const BinOpInfo &Ops) {
3097  unsigned IID;
3098  unsigned OpID = 0;
3099 
3100  bool isSigned = Ops.Ty->isSignedIntegerOrEnumerationType();
3101  switch (Ops.Opcode) {
3102  case BO_Add:
3103  case BO_AddAssign:
3104  OpID = 1;
3105  IID = isSigned ? llvm::Intrinsic::sadd_with_overflow :
3106  llvm::Intrinsic::uadd_with_overflow;
3107  break;
3108  case BO_Sub:
3109  case BO_SubAssign:
3110  OpID = 2;
3111  IID = isSigned ? llvm::Intrinsic::ssub_with_overflow :
3112  llvm::Intrinsic::usub_with_overflow;
3113  break;
3114  case BO_Mul:
3115  case BO_MulAssign:
3116  OpID = 3;
3117  IID = isSigned ? llvm::Intrinsic::smul_with_overflow :
3118  llvm::Intrinsic::umul_with_overflow;
3119  break;
3120  default:
3121  llvm_unreachable("Unsupported operation for overflow detection");
3122  }
3123  OpID <<= 1;
3124  if (isSigned)
3125  OpID |= 1;
3126 
3127  CodeGenFunction::SanitizerScope SanScope(&CGF);
3128  llvm::Type *opTy = CGF.CGM.getTypes().ConvertType(Ops.Ty);
3129 
3130  llvm::Function *intrinsic = CGF.CGM.getIntrinsic(IID, opTy);
3131 
3132  Value *resultAndOverflow = Builder.CreateCall(intrinsic, {Ops.LHS, Ops.RHS});
3133  Value *result = Builder.CreateExtractValue(resultAndOverflow, 0);
3134  Value *overflow = Builder.CreateExtractValue(resultAndOverflow, 1);
3135 
3136  // Handle overflow with llvm.trap if no custom handler has been specified.
3137  const std::string *handlerName =
3139  if (handlerName->empty()) {
3140  // If the signed-integer-overflow sanitizer is enabled, emit a call to its
3141  // runtime. Otherwise, this is a -ftrapv check, so just emit a trap.
3142  if (!isSigned || CGF.SanOpts.has(SanitizerKind::SignedIntegerOverflow)) {
3143  llvm::Value *NotOverflow = Builder.CreateNot(overflow);
3144  SanitizerMask Kind = isSigned ? SanitizerKind::SignedIntegerOverflow
3145  : SanitizerKind::UnsignedIntegerOverflow;
3146  EmitBinOpCheck(std::make_pair(NotOverflow, Kind), Ops);
3147  } else
3148  CGF.EmitTrapCheck(Builder.CreateNot(overflow));
3149  return result;
3150  }
3151 
3152  // Branch in case of overflow.
3153  llvm::BasicBlock *initialBB = Builder.GetInsertBlock();
3154  llvm::BasicBlock *continueBB =
3155  CGF.createBasicBlock("nooverflow", CGF.CurFn, initialBB->getNextNode());
3156  llvm::BasicBlock *overflowBB = CGF.createBasicBlock("overflow", CGF.CurFn);
3157 
3158  Builder.CreateCondBr(overflow, overflowBB, continueBB);
3159 
3160  // If an overflow handler is set, then we want to call it and then use its
3161  // result, if it returns.
3162  Builder.SetInsertPoint(overflowBB);
3163 
3164  // Get the overflow handler.
3165  llvm::Type *Int8Ty = CGF.Int8Ty;
3166  llvm::Type *argTypes[] = { CGF.Int64Ty, CGF.Int64Ty, Int8Ty, Int8Ty };
3167  llvm::FunctionType *handlerTy =
3168  llvm::FunctionType::get(CGF.Int64Ty, argTypes, true);
3169  llvm::FunctionCallee handler =
3170  CGF.CGM.CreateRuntimeFunction(handlerTy, *handlerName);
3171 
3172  // Sign extend the args to 64-bit, so that we can use the same handler for
3173  // all types of overflow.
3174  llvm::Value *lhs = Builder.CreateSExt(Ops.LHS, CGF.Int64Ty);
3175  llvm::Value *rhs = Builder.CreateSExt(Ops.RHS, CGF.Int64Ty);
3176 
3177  // Call the handler with the two arguments, the operation, and the size of
3178  // the result.
3179  llvm::Value *handlerArgs[] = {
3180  lhs,
3181  rhs,
3182  Builder.getInt8(OpID),
3183  Builder.getInt8(cast<llvm::IntegerType>(opTy)->getBitWidth())
3184  };
3185  llvm::Value *handlerResult =
3186  CGF.EmitNounwindRuntimeCall(handler, handlerArgs);
3187 
3188  // Truncate the result back to the desired size.
3189  handlerResult = Builder.CreateTrunc(handlerResult, opTy);
3190  Builder.CreateBr(continueBB);
3191 
3192  Builder.SetInsertPoint(continueBB);
3193  llvm::PHINode *phi = Builder.CreatePHI(opTy, 2);
3194  phi->addIncoming(result, initialBB);
3195  phi->addIncoming(handlerResult, overflowBB);
3196 
3197  return phi;
3198 }
3199 
3200 /// Emit pointer + index arithmetic.
3202  const BinOpInfo &op,
3203  bool isSubtraction) {
3204  // Must have binary (not unary) expr here. Unary pointer
3205  // increment/decrement doesn't use this path.
3206  const BinaryOperator *expr = cast<BinaryOperator>(op.E);
3207 
3208  Value *pointer = op.LHS;
3209  Expr *pointerOperand = expr->getLHS();
3210  Value *index = op.RHS;
3211  Expr *indexOperand = expr->getRHS();
3212 
3213  // In a subtraction, the LHS is always the pointer.
3214  if (!isSubtraction && !pointer->getType()->isPointerTy()) {
3215  std::swap(pointer, index);
3216  std::swap(pointerOperand, indexOperand);
3217  }
3218 
3219  bool isSigned = indexOperand->getType()->isSignedIntegerOrEnumerationType();
3220 
3221  unsigned width = cast<llvm::IntegerType>(index->getType())->getBitWidth();
3222  auto &DL = CGF.CGM.getDataLayout();
3223  auto PtrTy = cast<llvm::PointerType>(pointer->getType());
3224 
3225  // Some versions of glibc and gcc use idioms (particularly in their malloc
3226  // routines) that add a pointer-sized integer (known to be a pointer value)
3227  // to a null pointer in order to cast the value back to an integer or as
3228  // part of a pointer alignment algorithm. This is undefined behavior, but
3229  // we'd like to be able to compile programs that use it.
3230  //
3231  // Normally, we'd generate a GEP with a null-pointer base here in response
3232  // to that code, but it's also UB to dereference a pointer created that
3233  // way. Instead (as an acknowledged hack to tolerate the idiom) we will
3234  // generate a direct cast of the integer value to a pointer.
3235  //
3236  // The idiom (p = nullptr + N) is not met if any of the following are true:
3237  //
3238  // The operation is subtraction.
3239  // The index is not pointer-sized.
3240  // The pointer type is not byte-sized.
3241  //
3243  op.Opcode,
3244  expr->getLHS(),
3245  expr->getRHS()))
3246  return CGF.Builder.CreateIntToPtr(index, pointer->getType());
3247 
3248  if (width != DL.getTypeSizeInBits(PtrTy)) {
3249  // Zero-extend or sign-extend the pointer value according to
3250  // whether the index is signed or not.
3251  index = CGF.Builder.CreateIntCast(index, DL.getIntPtrType(PtrTy), isSigned,
3252  "idx.ext");
3253  }
3254 
3255  // If this is subtraction, negate the index.
3256  if (isSubtraction)
3257  index = CGF.Builder.CreateNeg(index, "idx.neg");
3258 
3259  if (CGF.SanOpts.has(SanitizerKind::ArrayBounds))
3260  CGF.EmitBoundsCheck(op.E, pointerOperand, index, indexOperand->getType(),
3261  /*Accessed*/ false);
3262 
3263  const PointerType *pointerType
3264  = pointerOperand->getType()->getAs<PointerType>();
3265  if (!pointerType) {
3266  QualType objectType = pointerOperand->getType()
3268  ->getPointeeType();
3269  llvm::Value *objectSize
3270  = CGF.CGM.getSize(CGF.getContext().getTypeSizeInChars(objectType));
3271 
3272  index = CGF.Builder.CreateMul(index, objectSize);
3273 
3274  Value *result = CGF.Builder.CreateBitCast(pointer, CGF.VoidPtrTy);
3275  result = CGF.Builder.CreateGEP(result, index, "add.ptr");
3276  return CGF.Builder.CreateBitCast(result, pointer->getType());
3277  }
3278 
3279  QualType elementType = pointerType->getPointeeType();
3280  if (const VariableArrayType *vla
3281  = CGF.getContext().getAsVariableArrayType(elementType)) {
3282  // The element count here is the total number of non-VLA elements.
3283  llvm::Value *numElements = CGF.getVLASize(vla).NumElts;
3284 
3285  // Effectively, the multiply by the VLA size is part of the GEP.
3286  // GEP indexes are signed, and scaling an index isn't permitted to
3287  // signed-overflow, so we use the same semantics for our explicit
3288  // multiply. We suppress this if overflow is not undefined behavior.
3289  if (CGF.getLangOpts().isSignedOverflowDefined()) {
3290  index = CGF.Builder.CreateMul(index, numElements, "vla.index");
3291  pointer = CGF.Builder.CreateGEP(pointer, index, "add.ptr");
3292  } else {
3293  index = CGF.Builder.CreateNSWMul(index, numElements, "vla.index");
3294  pointer =
3295  CGF.EmitCheckedInBoundsGEP(pointer, index, isSigned, isSubtraction,
3296  op.E->getExprLoc(), "add.ptr");
3297  }
3298  return pointer;
3299  }
3300 
3301  // Explicitly handle GNU void* and function pointer arithmetic extensions. The
3302  // GNU void* casts amount to no-ops since our void* type is i8*, but this is
3303  // future proof.
3304  if (elementType->isVoidType() || elementType->isFunctionType()) {
3305  Value *result = CGF.Builder.CreateBitCast(pointer, CGF.VoidPtrTy);
3306  result = CGF.Builder.CreateGEP(result, index, "add.ptr");
3307  return CGF.Builder.CreateBitCast(result, pointer->getType());
3308  }
3309 
3311  return CGF.Builder.CreateGEP(pointer, index, "add.ptr");
3312 
3313  return CGF.EmitCheckedInBoundsGEP(pointer, index, isSigned, isSubtraction,
3314  op.E->getExprLoc(), "add.ptr");
3315 }
3316 
3317 // Construct an fmuladd intrinsic to represent a fused mul-add of MulOp and
3318 // Addend. Use negMul and negAdd to negate the first operand of the Mul or
3319 // the add operand respectively. This allows fmuladd to represent a*b-c, or
3320 // c-a*b. Patterns in LLVM should catch the negated forms and translate them to
3321 // efficient operations.
3322 static Value* buildFMulAdd(llvm::BinaryOperator *MulOp, Value *Addend,
3323  const CodeGenFunction &CGF, CGBuilderTy &Builder,
3324  bool negMul, bool negAdd) {
3325  assert(!(negMul && negAdd) && "Only one of negMul and negAdd should be set.");
3326 
3327  Value *MulOp0 = MulOp->getOperand(0);
3328  Value *MulOp1 = MulOp->getOperand(1);
3329  if (negMul) {
3330  MulOp0 =
3331  Builder.CreateFSub(
3332  llvm::ConstantFP::getZeroValueForNegation(MulOp0->getType()), MulOp0,
3333  "neg");
3334  } else if (negAdd) {
3335  Addend =
3336  Builder.CreateFSub(
3337  llvm::ConstantFP::getZeroValueForNegation(Addend->getType()), Addend,
3338  "neg");
3339  }
3340 
3341  Value *FMulAdd = Builder.CreateCall(
3342  CGF.CGM.getIntrinsic(llvm::Intrinsic::fmuladd, Addend->getType()),
3343  {MulOp0, MulOp1, Addend});
3344  MulOp->eraseFromParent();
3345 
3346  return FMulAdd;
3347 }
3348 
3349 // Check whether it would be legal to emit an fmuladd intrinsic call to
3350 // represent op and if so, build the fmuladd.
3351 //
3352 // Checks that (a) the operation is fusable, and (b) -ffp-contract=on.
3353 // Does NOT check the type of the operation - it's assumed that this function
3354 // will be called from contexts where it's known that the type is contractable.
3355 static Value* tryEmitFMulAdd(const BinOpInfo &op,
3356  const CodeGenFunction &CGF, CGBuilderTy &Builder,
3357  bool isSub=false) {
3358 
3359  assert((op.Opcode == BO_Add || op.Opcode == BO_AddAssign ||
3360  op.Opcode == BO_Sub || op.Opcode == BO_SubAssign) &&
3361  "Only fadd/fsub can be the root of an fmuladd.");
3362 
3363  // Check whether this op is marked as fusable.
3364  if (!op.FPFeatures.allowFPContractWithinStatement())
3365  return nullptr;
3366 
3367  // We have a potentially fusable op. Look for a mul on one of the operands.
3368  // Also, make sure that the mul result isn't used directly. In that case,
3369  // there's no point creating a muladd operation.
3370  if (auto *LHSBinOp = dyn_cast<llvm::BinaryOperator>(op.LHS)) {
3371  if (LHSBinOp->getOpcode() == llvm::Instruction::FMul &&
3372  LHSBinOp->use_empty())
3373  return buildFMulAdd(LHSBinOp, op.RHS, CGF, Builder, false, isSub);
3374  }
3375  if (auto *RHSBinOp = dyn_cast<llvm::BinaryOperator>(op.RHS)) {
3376  if (RHSBinOp->getOpcode() == llvm::Instruction::FMul &&
3377  RHSBinOp->use_empty())
3378  return buildFMulAdd(RHSBinOp, op.LHS, CGF, Builder, isSub, false);
3379  }
3380 
3381  return nullptr;
3382 }
3383 
3384 Value *ScalarExprEmitter::EmitAdd(const BinOpInfo &op) {
3385  if (op.LHS->getType()->isPointerTy() ||
3386  op.RHS->getType()->isPointerTy())
3388 
3389  if (op.Ty->isSignedIntegerOrEnumerationType()) {
3390  switch (CGF.getLangOpts().getSignedOverflowBehavior()) {
3392  return Builder.CreateAdd(op.LHS, op.RHS, "add");
3394  if (!CGF.SanOpts.has(SanitizerKind::SignedIntegerOverflow))
3395  return Builder.CreateNSWAdd(op.LHS, op.RHS, "add");
3396  LLVM_FALLTHROUGH;
3398  if (CanElideOverflowCheck(CGF.getContext(), op))
3399  return Builder.CreateNSWAdd(op.LHS, op.RHS, "add");
3400  return EmitOverflowCheckedBinOp(op);
3401  }
3402  }
3403 
3404  if (op.Ty->isUnsignedIntegerType() &&
3405  CGF.SanOpts.has(SanitizerKind::UnsignedIntegerOverflow) &&
3406  !CanElideOverflowCheck(CGF.getContext(), op))
3407  return EmitOverflowCheckedBinOp(op);
3408 
3409  if (op.LHS->getType()->isFPOrFPVectorTy()) {
3410  // Try to form an fmuladd.
3411  if (Value *FMulAdd = tryEmitFMulAdd(op, CGF, Builder))
3412  return FMulAdd;
3413 
3414  Value *V = Builder.CreateFAdd(op.LHS, op.RHS, "add");
3415  return propagateFMFlags(V, op);
3416  }
3417 
3418  if (op.isFixedPointBinOp())
3419  return EmitFixedPointBinOp(op);
3420 
3421  return Builder.CreateAdd(op.LHS, op.RHS, "add");
3422 }
3423 
3424 /// The resulting value must be calculated with exact precision, so the operands
3425 /// may not be the same type.
3426 Value *ScalarExprEmitter::EmitFixedPointBinOp(const BinOpInfo &op) {
3427  using llvm::APSInt;
3428  using llvm::ConstantInt;
3429 
3430  const auto *BinOp = cast<BinaryOperator>(op.E);
3431 
3432  // The result is a fixed point type and at least one of the operands is fixed
3433  // point while the other is either fixed point or an int. This resulting type
3434  // should be determined by Sema::handleFixedPointConversions().
3435  QualType ResultTy = op.Ty;
3436  QualType LHSTy = BinOp->getLHS()->getType();
3437  QualType RHSTy = BinOp->getRHS()->getType();
3438  ASTContext &Ctx = CGF.getContext();
3439  Value *LHS = op.LHS;
3440  Value *RHS = op.RHS;
3441 
3442  auto LHSFixedSema = Ctx.getFixedPointSemantics(LHSTy);
3443  auto RHSFixedSema = Ctx.getFixedPointSemantics(RHSTy);
3444  auto ResultFixedSema = Ctx.getFixedPointSemantics(ResultTy);
3445  auto CommonFixedSema = LHSFixedSema.getCommonSemantics(RHSFixedSema);
3446 
3447  // Convert the operands to the full precision type.
3448  Value *FullLHS = EmitFixedPointConversion(LHS, LHSFixedSema, CommonFixedSema,
3449  BinOp->getExprLoc());
3450  Value *FullRHS = EmitFixedPointConversion(RHS, RHSFixedSema, CommonFixedSema,
3451  BinOp->getExprLoc());
3452 
3453  // Perform the actual addition.
3454  Value *Result;
3455  switch (BinOp->getOpcode()) {
3456  case BO_Add: {
3457  if (ResultFixedSema.isSaturated()) {
3458  llvm::Intrinsic::ID IID = ResultFixedSema.isSigned()
3459  ? llvm::Intrinsic::sadd_sat
3460  : llvm::Intrinsic::uadd_sat;
3461  Result = Builder.CreateBinaryIntrinsic(IID, FullLHS, FullRHS);
3462  } else {
3463  Result = Builder.CreateAdd(FullLHS, FullRHS);
3464  }
3465  break;
3466  }
3467  case BO_Sub: {
3468  if (ResultFixedSema.isSaturated()) {
3469  llvm::Intrinsic::ID IID = ResultFixedSema.isSigned()
3470  ? llvm::Intrinsic::ssub_sat
3471  : llvm::Intrinsic::usub_sat;
3472  Result = Builder.CreateBinaryIntrinsic(IID, FullLHS, FullRHS);
3473  } else {
3474  Result = Builder.CreateSub(FullLHS, FullRHS);
3475  }
3476  break;
3477  }
3478  case BO_LT:
3479  return CommonFixedSema.isSigned() ? Builder.CreateICmpSLT(FullLHS, FullRHS)
3480  : Builder.CreateICmpULT(FullLHS, FullRHS);
3481  case BO_GT:
3482  return CommonFixedSema.isSigned() ? Builder.CreateICmpSGT(FullLHS, FullRHS)
3483  : Builder.CreateICmpUGT(FullLHS, FullRHS);
3484  case BO_LE:
3485  return CommonFixedSema.isSigned() ? Builder.CreateICmpSLE(FullLHS, FullRHS)
3486  : Builder.CreateICmpULE(FullLHS, FullRHS);
3487  case BO_GE:
3488  return CommonFixedSema.isSigned() ? Builder.CreateICmpSGE(FullLHS, FullRHS)
3489  : Builder.CreateICmpUGE(FullLHS, FullRHS);
3490  case BO_EQ:
3491  // For equality operations, we assume any padding bits on unsigned types are
3492  // zero'd out. They could be overwritten through non-saturating operations
3493  // that cause overflow, but this leads to undefined behavior.
3494  return Builder.CreateICmpEQ(FullLHS, FullRHS);
3495  case BO_NE:
3496  return Builder.CreateICmpNE(FullLHS, FullRHS);
3497  case BO_Mul:
3498  case BO_Div:
3499  case BO_Shl:
3500  case BO_Shr:
3501  case BO_Cmp:
3502  case BO_LAnd:
3503  case BO_LOr:
3504  case BO_MulAssign:
3505  case BO_DivAssign:
3506  case BO_AddAssign:
3507  case BO_SubAssign:
3508  case BO_ShlAssign:
3509  case BO_ShrAssign:
3510  llvm_unreachable("Found unimplemented fixed point binary operation");
3511  case BO_PtrMemD:
3512  case BO_PtrMemI:
3513  case BO_Rem:
3514  case BO_Xor:
3515  case BO_And:
3516  case BO_Or:
3517  case BO_Assign:
3518  case BO_RemAssign:
3519  case BO_AndAssign:
3520  case BO_XorAssign:
3521  case BO_OrAssign:
3522  case BO_Comma:
3523  llvm_unreachable("Found unsupported binary operation for fixed point types.");
3524  }
3525 
3526  // Convert to the result type.
3527  return EmitFixedPointConversion(Result, CommonFixedSema, ResultFixedSema,
3528  BinOp->getExprLoc());
3529 }
3530 
3531 Value *ScalarExprEmitter::EmitSub(const BinOpInfo &op) {
3532  // The LHS is always a pointer if either side is.
3533  if (!op.LHS->getType()->isPointerTy()) {
3534  if (op.Ty->isSignedIntegerOrEnumerationType()) {
3535  switch (CGF.getLangOpts().getSignedOverflowBehavior()) {
3537  return Builder.CreateSub(op.LHS, op.RHS, "sub");
3539  if (!CGF.SanOpts.has(SanitizerKind::SignedIntegerOverflow))
3540  return Builder.CreateNSWSub(op.LHS, op.RHS, "sub");
3541  LLVM_FALLTHROUGH;
3543  if (CanElideOverflowCheck(CGF.getContext(), op))
3544  return Builder.CreateNSWSub(op.LHS, op.RHS, "sub");
3545  return EmitOverflowCheckedBinOp(op);
3546  }
3547  }
3548 
3549  if (op.Ty->isUnsignedIntegerType() &&
3550  CGF.SanOpts.has(SanitizerKind::UnsignedIntegerOverflow) &&
3551  !CanElideOverflowCheck(CGF.getContext(), op))
3552  return EmitOverflowCheckedBinOp(op);
3553 
3554  if (op.LHS->getType()->isFPOrFPVectorTy()) {
3555  // Try to form an fmuladd.
3556  if (Value *FMulAdd = tryEmitFMulAdd(op, CGF, Builder, true))
3557  return FMulAdd;
3558  Value *V = Builder.CreateFSub(op.LHS, op.RHS, "sub");
3559  return propagateFMFlags(V, op);
3560  }
3561 
3562  if (op.isFixedPointBinOp())
3563  return EmitFixedPointBinOp(op);
3564 
3565  return Builder.CreateSub(op.LHS, op.RHS, "sub");
3566  }
3567 
3568  // If the RHS is not a pointer, then we have normal pointer
3569  // arithmetic.
3570  if (!op.RHS->getType()->isPointerTy())
3572 
3573  // Otherwise, this is a pointer subtraction.
3574 
3575  // Do the raw subtraction part.
3576  llvm::Value *LHS
3577  = Builder.CreatePtrToInt(op.LHS, CGF.PtrDiffTy, "sub.ptr.lhs.cast");
3578  llvm::Value *RHS
3579  = Builder.CreatePtrToInt(op.RHS, CGF.PtrDiffTy, "sub.ptr.rhs.cast");
3580  Value *diffInChars = Builder.CreateSub(LHS, RHS, "sub.ptr.sub");
3581 
3582  // Okay, figure out the element size.
3583  const BinaryOperator *expr = cast<BinaryOperator>(op.E);
3584  QualType elementType = expr->getLHS()->getType()->getPointeeType();
3585 
3586  llvm::Value *divisor = nullptr;
3587 
3588  // For a variable-length array, this is going to be non-constant.
3589  if (const VariableArrayType *vla
3590  = CGF.getContext().getAsVariableArrayType(elementType)) {
3591  auto VlaSize = CGF.getVLASize(vla);
3592  elementType = VlaSize.Type;
3593  divisor = VlaSize.NumElts;
3594 
3595  // Scale the number of non-VLA elements by the non-VLA element size.
3596  CharUnits eltSize = CGF.getContext().getTypeSizeInChars(elementType);
3597  if (!eltSize.isOne())
3598  divisor = CGF.Builder.CreateNUWMul(CGF.CGM.getSize(eltSize), divisor);
3599 
3600  // For everything elese, we can just compute it, safe in the
3601  // assumption that Sema won't let anything through that we can't
3602  // safely compute the size of.
3603  } else {
3604  CharUnits elementSize;
3605  // Handle GCC extension for pointer arithmetic on void* and
3606  // function pointer types.
3607  if (elementType->isVoidType() || elementType->isFunctionType())
3608  elementSize = CharUnits::One();
3609  else
3610  elementSize = CGF.getContext().getTypeSizeInChars(elementType);
3611 
3612  // Don't even emit the divide for element size of 1.
3613  if (elementSize.isOne())
3614  return diffInChars;
3615 
3616  divisor = CGF.CGM.getSize(elementSize);
3617  }
3618 
3619  // Otherwise, do a full sdiv. This uses the "exact" form of sdiv, since
3620  // pointer difference in C is only defined in the case where both operands
3621  // are pointing to elements of an array.
3622  return Builder.CreateExactSDiv(diffInChars, divisor, "sub.ptr.div");
3623 }
3624 
3625 Value *ScalarExprEmitter::GetWidthMinusOneValue(Value* LHS,Value* RHS) {
3626  llvm::IntegerType *Ty;
3627  if (llvm::VectorType *VT = dyn_cast<llvm::VectorType>(LHS->getType()))
3628  Ty = cast<llvm::IntegerType>(VT->getElementType());
3629  else
3630  Ty = cast<llvm::IntegerType>(LHS->getType());
3631  return llvm::ConstantInt::get(RHS->getType(), Ty->getBitWidth() - 1);
3632 }
3633 
3634 Value *ScalarExprEmitter::EmitShl(const BinOpInfo &Ops) {
3635  // LLVM requires the LHS and RHS to be the same type: promote or truncate the
3636  // RHS to the same size as the LHS.
3637  Value *RHS = Ops.RHS;
3638  if (Ops.LHS->getType() != RHS->getType())
3639  RHS = Builder.CreateIntCast(RHS, Ops.LHS->getType(), false, "sh_prom");
3640 
3641  bool SanitizeBase = CGF.SanOpts.has(SanitizerKind::ShiftBase) &&
3642  Ops.Ty->hasSignedIntegerRepresentation() &&
3644  bool SanitizeExponent = CGF.SanOpts.has(SanitizerKind::ShiftExponent);
3645  // OpenCL 6.3j: shift values are effectively % word size of LHS.
3646  if (CGF.getLangOpts().OpenCL)
3647  RHS =
3648  Builder.CreateAnd(RHS, GetWidthMinusOneValue(Ops.LHS, RHS), "shl.mask");
3649  else if ((SanitizeBase || SanitizeExponent) &&
3650  isa<llvm::IntegerType>(Ops.LHS->getType())) {
3651  CodeGenFunction::SanitizerScope SanScope(&CGF);
3653  llvm::Value *WidthMinusOne = GetWidthMinusOneValue(Ops.LHS, Ops.RHS);
3654  llvm::Value *ValidExponent = Builder.CreateICmpULE(Ops.RHS, WidthMinusOne);
3655 
3656  if (SanitizeExponent) {
3657  Checks.push_back(
3658  std::make_pair(ValidExponent, SanitizerKind::ShiftExponent));
3659  }
3660 
3661  if (SanitizeBase) {
3662  // Check whether we are shifting any non-zero bits off the top of the
3663  // integer. We only emit this check if exponent is valid - otherwise
3664  // instructions below will have undefined behavior themselves.
3665  llvm::BasicBlock *Orig = Builder.GetInsertBlock();
3666  llvm::BasicBlock *Cont = CGF.createBasicBlock("cont");
3667  llvm::BasicBlock *CheckShiftBase = CGF.createBasicBlock("check");
3668  Builder.CreateCondBr(ValidExponent, CheckShiftBase, Cont);
3669  llvm::Value *PromotedWidthMinusOne =
3670  (RHS == Ops.RHS) ? WidthMinusOne
3671  : GetWidthMinusOneValue(Ops.LHS, RHS);
3672  CGF.EmitBlock(CheckShiftBase);
3673  llvm::Value *BitsShiftedOff = Builder.CreateLShr(
3674  Ops.LHS, Builder.CreateSub(PromotedWidthMinusOne, RHS, "shl.zeros",
3675  /*NUW*/ true, /*NSW*/ true),
3676  "shl.check");
3677  if (CGF.getLangOpts().CPlusPlus) {
3678  // In C99, we are not permitted to shift a 1 bit into the sign bit.
3679  // Under C++11's rules, shifting a 1 bit into the sign bit is
3680  // OK, but shifting a 1 bit out of it is not. (C89 and C++03 don't
3681  // define signed left shifts, so we use the C99 and C++11 rules there).
3682  llvm::Value *One = llvm::ConstantInt::get(BitsShiftedOff->getType(), 1);
3683  BitsShiftedOff = Builder.CreateLShr(BitsShiftedOff, One);
3684  }
3685  llvm::Value *Zero = llvm::ConstantInt::get(BitsShiftedOff->getType(), 0);
3686  llvm::Value *ValidBase = Builder.CreateICmpEQ(BitsShiftedOff, Zero);
3687  CGF.EmitBlock(Cont);
3688  llvm::PHINode *BaseCheck = Builder.CreatePHI(ValidBase->getType(), 2);
3689  BaseCheck->addIncoming(Builder.getTrue(), Orig);
3690  BaseCheck->addIncoming(ValidBase, CheckShiftBase);
3691  Checks.push_back(std::make_pair(BaseCheck, SanitizerKind::ShiftBase));
3692  }
3693 
3694  assert(!Checks.empty());
3695  EmitBinOpCheck(Checks, Ops);
3696  }
3697 
3698  return Builder.CreateShl(Ops.LHS, RHS, "shl");
3699 }
3700 
3701 Value *ScalarExprEmitter::EmitShr(const BinOpInfo &Ops) {
3702  // LLVM requires the LHS and RHS to be the same type: promote or truncate the
3703  // RHS to the same size as the LHS.
3704  Value *RHS = Ops.RHS;
3705  if (Ops.LHS->getType() != RHS->getType())
3706  RHS = Builder.CreateIntCast(RHS, Ops.LHS->getType(), false, "sh_prom");
3707 
3708  // OpenCL 6.3j: shift values are effectively % word size of LHS.
3709  if (CGF.getLangOpts().OpenCL)
3710  RHS =
3711  Builder.CreateAnd(RHS, GetWidthMinusOneValue(Ops.LHS, RHS), "shr.mask");
3712  else if (CGF.SanOpts.has(SanitizerKind::ShiftExponent) &&
3713  isa<llvm::IntegerType>(Ops.LHS->getType())) {
3714  CodeGenFunction::SanitizerScope SanScope(&CGF);
3715  llvm::Value *Valid =
3716  Builder.CreateICmpULE(RHS, GetWidthMinusOneValue(Ops.LHS, RHS));
3717  EmitBinOpCheck(std::make_pair(Valid, SanitizerKind::ShiftExponent), Ops);
3718  }
3719 
3720  if (Ops.Ty->hasUnsignedIntegerRepresentation())
3721  return Builder.CreateLShr(Ops.LHS, RHS, "shr");
3722  return Builder.CreateAShr(Ops.LHS, RHS, "shr");
3723 }
3724 
3726 // return corresponding comparison intrinsic for given vector type
3728  BuiltinType::Kind ElemKind) {
3729  switch (ElemKind) {
3730  default: llvm_unreachable("unexpected element type");
3731  case BuiltinType::Char_U:
3732  case BuiltinType::UChar:
3733  return (IT == VCMPEQ) ? llvm::Intrinsic::ppc_altivec_vcmpequb_p :
3734  llvm::Intrinsic::ppc_altivec_vcmpgtub_p;
3735  case BuiltinType::Char_S:
3736  case BuiltinType::SChar:
3737  return (IT == VCMPEQ) ? llvm::Intrinsic::ppc_altivec_vcmpequb_p :
3738  llvm::Intrinsic::ppc_altivec_vcmpgtsb_p;
3739  case BuiltinType::UShort:
3740  return (IT == VCMPEQ) ? llvm::Intrinsic::ppc_altivec_vcmpequh_p :
3741  llvm::Intrinsic::ppc_altivec_vcmpgtuh_p;
3742  case BuiltinType::Short:
3743  return (IT == VCMPEQ) ? llvm::Intrinsic::ppc_altivec_vcmpequh_p :
3744  llvm::Intrinsic::ppc_altivec_vcmpgtsh_p;
3745  case BuiltinType::UInt:
3746  return (IT == VCMPEQ) ? llvm::Intrinsic::ppc_altivec_vcmpequw_p :
3747  llvm::Intrinsic::ppc_altivec_vcmpgtuw_p;
3748  case BuiltinType::Int:
3749  return (IT == VCMPEQ) ? llvm::Intrinsic::ppc_altivec_vcmpequw_p :
3750  llvm::Intrinsic::ppc_altivec_vcmpgtsw_p;
3751  case BuiltinType::ULong:
3752  case BuiltinType::ULongLong:
3753  return (IT == VCMPEQ) ? llvm::Intrinsic::ppc_altivec_vcmpequd_p :
3754  llvm::Intrinsic::ppc_altivec_vcmpgtud_p;
3755  case BuiltinType::Long:
3756  case BuiltinType::LongLong:
3757  return (IT == VCMPEQ) ? llvm::Intrinsic::ppc_altivec_vcmpequd_p :
3758  llvm::Intrinsic::ppc_altivec_vcmpgtsd_p;
3759  case BuiltinType::Float:
3760  return (IT == VCMPEQ) ? llvm::Intrinsic::ppc_altivec_vcmpeqfp_p :
3761  llvm::Intrinsic::ppc_altivec_vcmpgtfp_p;
3762  case BuiltinType::Double:
3763  return (IT == VCMPEQ) ? llvm::Intrinsic::ppc_vsx_xvcmpeqdp_p :
3764  llvm::Intrinsic::ppc_vsx_xvcmpgtdp_p;
3765  }
3766 }
3767 
3769  llvm::CmpInst::Predicate UICmpOpc,
3770  llvm::CmpInst::Predicate SICmpOpc,
3771  llvm::CmpInst::Predicate FCmpOpc) {
3772  TestAndClearIgnoreResultAssign();
3773  Value *Result;
3774  QualType LHSTy = E->getLHS()->getType();
3775  QualType RHSTy = E->getRHS()->getType();
3776  if (const MemberPointerType *MPT = LHSTy->getAs<MemberPointerType>()) {
3777  assert(E->getOpcode() == BO_EQ ||
3778  E->getOpcode() == BO_NE);
3779  Value *LHS = CGF.EmitScalarExpr(E->getLHS());
3780  Value *RHS = CGF.EmitScalarExpr(E->getRHS());
3781  Result = CGF.CGM.getCXXABI().EmitMemberPointerComparison(
3782  CGF, LHS, RHS, MPT, E->getOpcode() == BO_NE);
3783  } else if (!LHSTy->isAnyComplexType() && !RHSTy->isAnyComplexType()) {
3784  BinOpInfo BOInfo = EmitBinOps(E);
3785  Value *LHS = BOInfo.LHS;
3786  Value *RHS = BOInfo.RHS;
3787 
3788  // If AltiVec, the comparison results in a numeric type, so we use
3789  // intrinsics comparing vectors and giving 0 or 1 as a result
3790  if (LHSTy->isVectorType() && !E->getType()->isVectorType()) {
3791  // constants for mapping CR6 register bits to predicate result
3792  enum { CR6_EQ=0, CR6_EQ_REV, CR6_LT, CR6_LT_REV } CR6;
3793 
3794  llvm::Intrinsic::ID ID = llvm::Intrinsic::not_intrinsic;
3795 
3796  // in several cases vector arguments order will be reversed
3797  Value *FirstVecArg = LHS,
3798  *SecondVecArg = RHS;
3799 
3800  QualType ElTy = LHSTy->getAs<VectorType>()->getElementType();
3801  const BuiltinType *BTy = ElTy->getAs<BuiltinType>();
3802  BuiltinType::Kind ElementKind = BTy->getKind();
3803 
3804  switch(E->getOpcode()) {
3805  default: llvm_unreachable("is not a comparison operation");
3806  case BO_EQ:
3807  CR6 = CR6_LT;
3808  ID = GetIntrinsic(VCMPEQ, ElementKind);
3809  break;
3810  case BO_NE:
3811  CR6 = CR6_EQ;
3812  ID = GetIntrinsic(VCMPEQ, ElementKind);
3813  break;
3814  case BO_LT:
3815  CR6 = CR6_LT;
3816  ID = GetIntrinsic(VCMPGT, ElementKind);
3817  std::swap(FirstVecArg, SecondVecArg);
3818  break;
3819  case BO_GT:
3820  CR6 = CR6_LT;
3821  ID = GetIntrinsic(VCMPGT, ElementKind);
3822  break;
3823  case BO_LE:
3824  if (ElementKind == BuiltinType::Float) {
3825  CR6 = CR6_LT;
3826  ID = llvm::Intrinsic::ppc_altivec_vcmpgefp_p;
3827  std::swap(FirstVecArg, SecondVecArg);
3828  }
3829  else {
3830  CR6 = CR6_EQ;
3831  ID = GetIntrinsic(VCMPGT, ElementKind);
3832  }
3833  break;
3834  case BO_GE:
3835  if (ElementKind == BuiltinType::Float) {
3836  CR6 = CR6_LT;
3837  ID = llvm::Intrinsic::ppc_altivec_vcmpgefp_p;
3838  }
3839  else {
3840  CR6 = CR6_EQ;
3841  ID = GetIntrinsic(VCMPGT, ElementKind);
3842  std::swap(FirstVecArg, SecondVecArg);
3843  }
3844  break;
3845  }
3846 
3847  Value *CR6Param = Builder.getInt32(CR6);
3848  llvm::Function *F = CGF.CGM.getIntrinsic(ID);
3849  Result = Builder.CreateCall(F, {CR6Param, FirstVecArg, SecondVecArg});
3850 
3851  // The result type of intrinsic may not be same as E->getType().
3852  // If E->getType() is not BoolTy, EmitScalarConversion will do the
3853  // conversion work. If E->getType() is BoolTy, EmitScalarConversion will
3854  // do nothing, if ResultTy is not i1 at the same time, it will cause
3855  // crash later.
3856  llvm::IntegerType *ResultTy = cast<llvm::IntegerType>(Result->getType());
3857  if (ResultTy->getBitWidth() > 1 &&
3858  E->getType() == CGF.getContext().BoolTy)
3859  Result = Builder.CreateTrunc(Result, Builder.getInt1Ty());
3860  return EmitScalarConversion(Result, CGF.getContext().BoolTy, E->getType(),
3861  E->getExprLoc());
3862  }
3863 
3864  if (BOInfo.isFixedPointBinOp()) {
3865  Result = EmitFixedPointBinOp(BOInfo);
3866  } else if (LHS->getType()->isFPOrFPVectorTy()) {
3867  Result = Builder.CreateFCmp(FCmpOpc, LHS, RHS, "cmp");
3868  } else if (LHSTy->hasSignedIntegerRepresentation()) {
3869  Result = Builder.CreateICmp(SICmpOpc, LHS, RHS, "cmp");
3870  } else {
3871  // Unsigned integers and pointers.
3872 
3873  if (CGF.CGM.getCodeGenOpts().StrictVTablePointers &&
3874  !isa<llvm::ConstantPointerNull>(LHS) &&
3875  !isa<llvm::ConstantPointerNull>(RHS)) {
3876 
3877  // Dynamic information is required to be stripped for comparisons,
3878  // because it could leak the dynamic information. Based on comparisons
3879  // of pointers to dynamic objects, the optimizer can replace one pointer
3880  // with another, which might be incorrect in presence of invariant
3881  // groups. Comparison with null is safe because null does not carry any
3882  // dynamic information.
3883  if (LHSTy.mayBeDynamicClass())
3884  LHS = Builder.CreateStripInvariantGroup(LHS);
3885  if (RHSTy.mayBeDynamicClass())
3886  RHS = Builder.CreateStripInvariantGroup(RHS);
3887  }
3888 
3889  Result = Builder.CreateICmp(UICmpOpc, LHS, RHS, "cmp");
3890  }
3891 
3892  // If this is a vector comparison, sign extend the result to the appropriate
3893  // vector integer type and return it (don't convert to bool).
3894  if (LHSTy->isVectorType())
3895  return Builder.CreateSExt(Result, ConvertType(E->getType()), "sext");
3896 
3897  } else {
3898  // Complex Comparison: can only be an equality comparison.
3900  QualType CETy;
3901  if (auto *CTy = LHSTy->getAs<ComplexType>()) {
3902  LHS = CGF.EmitComplexExpr(E->getLHS());
3903  CETy = CTy->getElementType();
3904  } else {
3905  LHS.first = Visit(E->getLHS());
3906  LHS.second = llvm::Constant::getNullValue(LHS.first->getType());
3907  CETy = LHSTy;
3908  }
3909  if (auto *CTy = RHSTy->getAs<ComplexType>()) {
3910  RHS = CGF.EmitComplexExpr(E->getRHS());
3911  assert(CGF.getContext().hasSameUnqualifiedType(CETy,
3912  CTy->getElementType()) &&
3913  "The element types must always match.");
3914  (void)CTy;
3915  } else {
3916  RHS.first = Visit(E->getRHS());
3917  RHS.second = llvm::Constant::getNullValue(RHS.first->getType());
3918  assert(CGF.getContext().hasSameUnqualifiedType(CETy, RHSTy) &&
3919  "The element types must always match.");
3920  }
3921 
3922  Value *ResultR, *ResultI;
3923  if (CETy->isRealFloatingType()) {
3924  ResultR = Builder.CreateFCmp(FCmpOpc, LHS.first, RHS.first, "cmp.r");
3925  ResultI = Builder.CreateFCmp(FCmpOpc, LHS.second, RHS.second, "cmp.i");
3926  } else {
3927  // Complex comparisons can only be equality comparisons. As such, signed
3928  // and unsigned opcodes are the same.
3929  ResultR = Builder.CreateICmp(UICmpOpc, LHS.first, RHS.first, "cmp.r");
3930  ResultI = Builder.CreateICmp(UICmpOpc, LHS.second, RHS.second, "cmp.i");
3931  }
3932 
3933  if (E->getOpcode() == BO_EQ) {
3934  Result = Builder.CreateAnd(ResultR, ResultI, "and.ri");
3935  } else {
3936  assert(E->getOpcode() == BO_NE &&
3937  "Complex comparison other than == or != ?");
3938  Result = Builder.CreateOr(ResultR, ResultI, "or.ri");
3939  }
3940  }
3941 
3942  return EmitScalarConversion(Result, CGF.getContext().BoolTy, E->getType(),
3943  E->getExprLoc());
3944 }
3945 
3946 Value *ScalarExprEmitter::VisitBinAssign(const BinaryOperator *E) {
3947  bool Ignore = TestAndClearIgnoreResultAssign();
3948 
3949  Value *RHS;
3950  LValue LHS;
3951 
3952  switch (E->getLHS()->getType().getObjCLifetime()) {
3954  std::tie(LHS, RHS) = CGF.EmitARCStoreStrong(E, Ignore);
3955  break;
3956 
3958  std::tie(LHS, RHS) = CGF.EmitARCStoreAutoreleasing(E);
3959  break;
3960 
3962  std::tie(LHS, RHS) = CGF.EmitARCStoreUnsafeUnretained(E, Ignore);
3963  break;
3964 
3965  case Qualifiers::OCL_Weak:
3966  RHS = Visit(E->getRHS());
3967  LHS = EmitCheckedLValue(E->getLHS(), CodeGenFunction::TCK_Store);
3968  RHS = CGF.EmitARCStoreWeak(LHS.getAddress(), RHS, Ignore);
3969  break;
3970 
3971  case Qualifiers::OCL_None:
3972  // __block variables need to have the rhs evaluated first, plus
3973  // this should improve codegen just a little.
3974  RHS = Visit(E->getRHS());
3975  LHS = EmitCheckedLValue(E->getLHS(), CodeGenFunction::TCK_Store);
3976 
3977  // Store the value into the LHS. Bit-fields are handled specially
3978  // because the result is altered by the store, i.e., [C99 6.5.16p1]
3979  // 'An assignment expression has the value of the left operand after
3980  // the assignment...'.
3981  if (LHS.isBitField()) {
3982  CGF.EmitStoreThroughBitfieldLValue(RValue::get(RHS), LHS, &RHS);
3983  } else {
3984  CGF.EmitNullabilityCheck(LHS, RHS, E->getExprLoc());
3985  CGF.EmitStoreThroughLValue(RValue::get(RHS), LHS);
3986  }
3987  }
3988 
3989  // If the result is clearly ignored, return now.
3990  if (Ignore)
3991  return nullptr;
3992 
3993  // The result of an assignment in C is the assigned r-value.
3994  if (!CGF.getLangOpts().CPlusPlus)
3995  return RHS;
3996 
3997  // If the lvalue is non-volatile, return the computed value of the assignment.
3998  if (!LHS.isVolatileQualified())
3999  return RHS;
4000 
4001  // Otherwise, reload the value.
4002  return EmitLoadOfLValue(LHS, E->getExprLoc());
4003 }
4004 
4005 Value *ScalarExprEmitter::VisitBinLAnd(const BinaryOperator *E) {
4006  // Perform vector logical and on comparisons with zero vectors.
4007  if (E->getType()->isVectorType()) {
4008  CGF.incrementProfileCounter(E);
4009 
4010  Value *LHS = Visit(E->getLHS());
4011  Value *RHS = Visit(E->getRHS());
4012  Value *Zero = llvm::ConstantAggregateZero::get(LHS->getType());
4013  if (LHS->getType()->isFPOrFPVectorTy()) {
4014  LHS = Builder.CreateFCmp(llvm::CmpInst::FCMP_UNE, LHS, Zero, "cmp");
4015  RHS = Builder.CreateFCmp(llvm::CmpInst::FCMP_UNE, RHS, Zero, "cmp");
4016  } else {
4017  LHS = Builder.CreateICmp(llvm::CmpInst::ICMP_NE, LHS, Zero, "cmp");
4018  RHS = Builder.CreateICmp(llvm::CmpInst::ICMP_NE, RHS, Zero, "cmp");
4019  }
4020  Value *And = Builder.CreateAnd(LHS, RHS);
4021  return Builder.CreateSExt(And, ConvertType(E->getType()), "sext");
4022  }
4023 
4024  llvm::Type *ResTy = ConvertType(E->getType());
4025 
4026  // If we have 0 && RHS, see if we can elide RHS, if so, just return 0.
4027  // If we have 1 && X, just emit X without inserting the control flow.
4028  bool LHSCondVal;
4029  if (CGF.ConstantFoldsToSimpleInteger(E->getLHS(), LHSCondVal)) {
4030  if (LHSCondVal) { // If we have 1 && X, just emit X.
4031  CGF.incrementProfileCounter(E);
4032 
4033  Value *RHSCond = CGF.EvaluateExprAsBool(E->getRHS());
4034  // ZExt result to int or bool.
4035  return Builder.CreateZExtOrBitCast(RHSCond, ResTy, "land.ext");
4036  }
4037 
4038  // 0 && RHS: If it is safe, just elide the RHS, and return 0/false.
4039  if (!CGF.ContainsLabel(E->getRHS()))
4040  return llvm::Constant::getNullValue(ResTy);
4041  }
4042 
4043  llvm::BasicBlock *ContBlock = CGF.createBasicBlock("land.end");
4044  llvm::BasicBlock *RHSBlock = CGF.createBasicBlock("land.rhs");
4045 
4047 
4048  // Branch on the LHS first. If it is false, go to the failure (cont) block.
4049  CGF.EmitBranchOnBoolExpr(E->getLHS(), RHSBlock, ContBlock,
4050  CGF.getProfileCount(E->getRHS()));
4051 
4052  // Any edges into the ContBlock are now from an (indeterminate number of)
4053  // edges from this first condition. All of these values will be false. Start
4054  // setting up the PHI node in the Cont Block for this.
4055  llvm::PHINode *PN = llvm::PHINode::Create(llvm::Type::getInt1Ty(VMContext), 2,
4056  "", ContBlock);
4057  for (llvm::pred_iterator PI = pred_begin(ContBlock), PE = pred_end(ContBlock);
4058  PI != PE; ++PI)
4059  PN->addIncoming(llvm::ConstantInt::getFalse(VMContext), *PI);
4060 
4061  eval.begin(CGF);
4062  CGF.EmitBlock(RHSBlock);
4063  CGF.incrementProfileCounter(E);
4064  Value *RHSCond = CGF.EvaluateExprAsBool(E->getRHS());
4065  eval.end(CGF);
4066 
4067  // Reaquire the RHS block, as there may be subblocks inserted.
4068  RHSBlock = Builder.GetInsertBlock();
4069 
4070  // Emit an unconditional branch from this block to ContBlock.
4071  {
4072  // There is no need to emit line number for unconditional branch.
4073  auto NL = ApplyDebugLocation::CreateEmpty(CGF);
4074  CGF.EmitBlock(ContBlock);
4075  }
4076  // Insert an entry into the phi node for the edge with the value of RHSCond.
4077  PN->addIncoming(RHSCond, RHSBlock);
4078 
4079  // Artificial location to preserve the scope information
4080  {
4081  auto NL = ApplyDebugLocation::CreateArtificial(CGF);
4082  PN->setDebugLoc(Builder.getCurrentDebugLocation());
4083  }
4084 
4085  // ZExt result to int.
4086  return Builder.CreateZExtOrBitCast(PN, ResTy, "land.ext");
4087 }
4088 
4089 Value *ScalarExprEmitter::VisitBinLOr(const BinaryOperator *E) {
4090  // Perform vector logical or on comparisons with zero vectors.
4091  if (E->getType()->isVectorType()) {
4092  CGF.incrementProfileCounter(E);
4093 
4094  Value *LHS = Visit(E->getLHS());
4095  Value *RHS = Visit(E->getRHS());
4096  Value *Zero = llvm::ConstantAggregateZero::get(LHS->getType());
4097  if (LHS->getType()->isFPOrFPVectorTy()) {
4098  LHS = Builder.CreateFCmp(llvm::CmpInst::FCMP_UNE, LHS, Zero, "cmp");
4099  RHS = Builder.CreateFCmp(llvm::CmpInst::FCMP_UNE, RHS, Zero, "cmp");
4100  } else {
4101  LHS = Builder.CreateICmp(llvm::CmpInst::ICMP_NE, LHS, Zero, "cmp");
4102  RHS = Builder.CreateICmp(llvm::CmpInst::ICMP_NE, RHS, Zero, "cmp");
4103  }
4104  Value *Or = Builder.CreateOr(LHS, RHS);
4105  return Builder.CreateSExt(Or, ConvertType(E->getType()), "sext");
4106  }
4107 
4108  llvm::Type *ResTy = ConvertType(E->getType());
4109 
4110  // If we have 1 || RHS, see if we can elide RHS, if so, just return 1.
4111  // If we have 0 || X, just emit X without inserting the control flow.
4112  bool LHSCondVal;
4113  if (CGF.ConstantFoldsToSimpleInteger(E->getLHS(), LHSCondVal)) {
4114  if (!LHSCondVal) { // If we have 0 || X, just emit X.
4115  CGF.incrementProfileCounter(E);
4116 
4117  Value *RHSCond = CGF.EvaluateExprAsBool(E->getRHS());
4118  // ZExt result to int or bool.
4119  return Builder.CreateZExtOrBitCast(RHSCond, ResTy, "lor.ext");
4120  }
4121 
4122  // 1 || RHS: If it is safe, just elide the RHS, and return 1/true.
4123  if (!CGF.ContainsLabel(E->getRHS()))
4124  return llvm::ConstantInt::get(ResTy, 1);
4125  }
4126 
4127  llvm::BasicBlock *ContBlock = CGF.createBasicBlock("lor.end");
4128  llvm::BasicBlock *RHSBlock = CGF.createBasicBlock("lor.rhs");
4129 
4131 
4132  // Branch on the LHS first. If it is true, go to the success (cont) block.
4133  CGF.EmitBranchOnBoolExpr(E->getLHS(), ContBlock, RHSBlock,
4134  CGF.getCurrentProfileCount() -
4135  CGF.getProfileCount(E->getRHS()));
4136 
4137  // Any edges into the ContBlock are now from an (indeterminate number of)
4138  // edges from this first condition. All of these values will be true. Start
4139  // setting up the PHI node in the Cont Block for this.
4140  llvm::PHINode *PN = llvm::PHINode::Create(llvm::Type::getInt1Ty(VMContext), 2,
4141  "", ContBlock);
4142  for (llvm::pred_iterator PI = pred_begin(ContBlock), PE = pred_end(ContBlock);
4143  PI != PE; ++PI)
4144  PN->addIncoming(llvm::ConstantInt::getTrue(VMContext), *PI);
4145 
4146  eval.begin(CGF);
4147 
4148  // Emit the RHS condition as a bool value.
4149  CGF.EmitBlock(RHSBlock);
4150  CGF.incrementProfileCounter(E);
4151  Value *RHSCond = CGF.EvaluateExprAsBool(E->getRHS());
4152 
4153  eval.end(CGF);
4154 
4155  // Reaquire the RHS block, as there may be subblocks inserted.
4156  RHSBlock = Builder.GetInsertBlock();
4157 
4158  // Emit an unconditional branch from this block to ContBlock. Insert an entry
4159  // into the phi node for the edge with the value of RHSCond.
4160  CGF.EmitBlock(ContBlock);
4161  PN->addIncoming(RHSCond, RHSBlock);
4162 
4163  // ZExt result to int.
4164  return Builder.CreateZExtOrBitCast(PN, ResTy, "lor.ext");
4165 }
4166 
4167 Value *ScalarExprEmitter::VisitBinComma(const BinaryOperator *E) {
4168  CGF.EmitIgnoredExpr(E->getLHS());
4169  CGF.EnsureInsertPoint();
4170  return Visit(E->getRHS());
4171 }
4172 
4173 //===----------------------------------------------------------------------===//
4174 // Other Operators
4175 //===----------------------------------------------------------------------===//
4176 
4177 /// isCheapEnoughToEvaluateUnconditionally - Return true if the specified
4178 /// expression is cheap enough and side-effect-free enough to evaluate
4179 /// unconditionally instead of conditionally. This is used to convert control
4180 /// flow into selects in some cases.
4182  CodeGenFunction &CGF) {
4183  // Anything that is an integer or floating point constant is fine.
4184  return E->IgnoreParens()->isEvaluatable(CGF.getContext());
4185 
4186  // Even non-volatile automatic variables can't be evaluated unconditionally.
4187  // Referencing a thread_local may cause non-trivial initialization work to
4188  // occur. If we're inside a lambda and one of the variables is from the scope
4189  // outside the lambda, that function may have returned already. Reading its
4190  // locals is a bad idea. Also, these reads may introduce races there didn't
4191  // exist in the source-level program.
4192 }
4193 
4194 
4195 Value *ScalarExprEmitter::
4196 VisitAbstractConditionalOperator(const AbstractConditionalOperator *E) {
4197  TestAndClearIgnoreResultAssign();
4198 
4199  // Bind the common expression if necessary.
4200  CodeGenFunction::OpaqueValueMapping binding(CGF, E);
4201 
4202  Expr *condExpr = E->getCond();
4203  Expr *lhsExpr = E->getTrueExpr();
4204  Expr *rhsExpr = E->getFalseExpr();
4205 
4206  // If the condition constant folds and can be elided, try to avoid emitting
4207  // the condition and the dead arm.
4208  bool CondExprBool;
4209  if (CGF.ConstantFoldsToSimpleInteger(condExpr, CondExprBool)) {
4210  Expr *live = lhsExpr, *dead = rhsExpr;
4211  if (!CondExprBool) std::swap(live, dead);
4212 
4213  // If the dead side doesn't have labels we need, just emit the Live part.
4214  if (!CGF.ContainsLabel(dead)) {
4215  if (CondExprBool)
4216  CGF.incrementProfileCounter(E);
4217  Value *Result = Visit(live);
4218 
4219  // If the live part is a throw expression, it acts like it has a void
4220  // type, so evaluating it returns a null Value*. However, a conditional
4221  // with non-void type must return a non-null Value*.
4222  if (!Result && !E->getType()->isVoidType())
4223  Result = llvm::UndefValue::get(CGF.ConvertType(E->getType()));
4224 
4225  return Result;
4226  }
4227  }
4228 
4229  // OpenCL: If the condition is a vector, we can treat this condition like
4230  // the select function.
4231  if (CGF.getLangOpts().OpenCL
4232  && condExpr->getType()->isVectorType()) {
4233  CGF.incrementProfileCounter(E);
4234 
4235  llvm::Value *CondV = CGF.EmitScalarExpr(condExpr);
4236  llvm::Value *LHS = Visit(lhsExpr);
4237  llvm::Value *RHS = Visit(rhsExpr);
4238 
4239  llvm::Type *condType = ConvertType(condExpr->getType());
4240  llvm::VectorType *vecTy = cast<llvm::VectorType>(condType);
4241 
4242  unsigned numElem = vecTy->getNumElements();
4243  llvm::Type *elemType = vecTy->getElementType();
4244 
4245  llvm::Value *zeroVec = llvm::Constant::getNullValue(vecTy);
4246  llvm::Value *TestMSB = Builder.CreateICmpSLT(CondV, zeroVec);
4247  llvm::Value *tmp = Builder.CreateSExt(TestMSB,
4248  llvm::VectorType::get(elemType,
4249  numElem),
4250  "sext");
4251  llvm::Value *tmp2 = Builder.CreateNot(tmp);
4252 
4253  // Cast float to int to perform ANDs if necessary.
4254  llvm::Value *RHSTmp = RHS;
4255  llvm::Value *LHSTmp = LHS;
4256  bool wasCast = false;
4257  llvm::VectorType *rhsVTy = cast<llvm::VectorType>(RHS->getType());
4258  if (rhsVTy->getElementType()->isFloatingPointTy()) {
4259  RHSTmp = Builder.CreateBitCast(RHS, tmp2->getType());
4260  LHSTmp = Builder.CreateBitCast(LHS, tmp->getType());
4261  wasCast = true;
4262  }
4263 
4264  llvm::Value *tmp3 = Builder.CreateAnd(RHSTmp, tmp2);
4265  llvm::Value *tmp4 = Builder.CreateAnd(LHSTmp, tmp);
4266  llvm::Value *tmp5 = Builder.CreateOr(tmp3, tmp4, "cond");
4267  if (wasCast)
4268  tmp5 = Builder.CreateBitCast(tmp5, RHS->getType());
4269 
4270  return tmp5;
4271  }
4272 
4273  // If this is a really simple expression (like x ? 4 : 5), emit this as a
4274  // select instead of as control flow. We can only do this if it is cheap and
4275  // safe to evaluate the LHS and RHS unconditionally.
4276  if (isCheapEnoughToEvaluateUnconditionally(lhsExpr, CGF) &&
4278  llvm::Value *CondV = CGF.EvaluateExprAsBool(condExpr);
4279  llvm::Value *StepV = Builder.CreateZExtOrBitCast(CondV, CGF.Int64Ty);
4280 
4281  CGF.incrementProfileCounter(E, StepV);
4282 
4283  llvm::Value *LHS = Visit(lhsExpr);
4284  llvm::Value *RHS = Visit(rhsExpr);
4285  if (!LHS) {
4286  // If the conditional has void type, make sure we return a null Value*.
4287  assert(!RHS && "LHS and RHS types must match");
4288  return nullptr;
4289  }
4290  return Builder.CreateSelect(CondV, LHS, RHS, "cond");
4291  }
4292 
4293  llvm::BasicBlock *LHSBlock = CGF.createBasicBlock("cond.true");
4294  llvm::BasicBlock *RHSBlock = CGF.createBasicBlock("cond.false");
4295  llvm::BasicBlock *ContBlock = CGF.createBasicBlock("cond.end");
4296 
4298  CGF.EmitBranchOnBoolExpr(condExpr, LHSBlock, RHSBlock,
4299  CGF.getProfileCount(lhsExpr));
4300 
4301  CGF.EmitBlock(LHSBlock);
4302  CGF.incrementProfileCounter(E);
4303  eval.begin(CGF);
4304  Value *LHS = Visit(lhsExpr);
4305  eval.end(CGF);
4306 
4307  LHSBlock = Builder.GetInsertBlock();
4308  Builder.CreateBr(ContBlock);
4309 
4310  CGF.EmitBlock(RHSBlock);
4311  eval.begin(CGF);
4312  Value *RHS = Visit(rhsExpr);
4313  eval.end(CGF);
4314 
4315  RHSBlock = Builder.GetInsertBlock();
4316  CGF.EmitBlock(ContBlock);
4317 
4318  // If the LHS or RHS is a throw expression, it will be legitimately null.
4319  if (!LHS)
4320  return RHS;
4321  if (!RHS)
4322  return LHS;
4323 
4324  // Create a PHI node for the real part.
4325  llvm::PHINode *PN = Builder.CreatePHI(LHS->getType(), 2, "cond");
4326  PN->addIncoming(LHS, LHSBlock);
4327  PN->addIncoming(RHS, RHSBlock);
4328  return PN;
4329 }
4330 
4331 Value *ScalarExprEmitter::VisitChooseExpr(ChooseExpr *E) {
4332  return Visit(E->getChosenSubExpr());
4333 }
4334 
4335 Value *ScalarExprEmitter::VisitVAArgExpr(VAArgExpr *VE) {
4336  QualType Ty = VE->getType();
4337 
4338  if (Ty->isVariablyModifiedType())
4339  CGF.EmitVariablyModifiedType(Ty);
4340 
4341  Address ArgValue = Address::invalid();
4342  Address ArgPtr = CGF.EmitVAArg(VE, ArgValue);
4343 
4344  llvm::Type *ArgTy = ConvertType(VE->getType());
4345 
4346  // If EmitVAArg fails, emit an error.
4347  if (!ArgPtr.isValid()) {
4348  CGF.ErrorUnsupported(VE, "va_arg expression");
4349  return llvm::UndefValue::get(ArgTy);
4350  }
4351 
4352  // FIXME Volatility.
4353  llvm::Value *Val = Builder.CreateLoad(ArgPtr);
4354 
4355  // If EmitVAArg promoted the type, we must truncate it.
4356  if (ArgTy != Val->getType()) {
4357  if (ArgTy->isPointerTy() && !Val->getType()->isPointerTy())
4358  Val = Builder.CreateIntToPtr(Val, ArgTy);
4359  else
4360  Val = Builder.CreateTrunc(Val, ArgTy);
4361  }
4362 
4363  return Val;
4364 }
4365 
4366 Value *ScalarExprEmitter::VisitBlockExpr(const BlockExpr *block) {
4367  return CGF.EmitBlockLiteral(block);
4368 }
4369 
4370 // Convert a vec3 to vec4, or vice versa.
4372  Value *Src, unsigned NumElementsDst) {
4373  llvm::Value *UnV = llvm::UndefValue::get(Src->getType());
4375  Args.push_back(Builder.getInt32(0));
4376  Args.push_back(Builder.getInt32(1));
4377  Args.push_back(Builder.getInt32(2));
4378  if (NumElementsDst == 4)
4379  Args.push_back(llvm::UndefValue::get(CGF.Int32Ty));
4380  llvm::Constant *Mask = llvm::ConstantVector::get(Args);
4381  return Builder.CreateShuffleVector(Src, UnV, Mask);
4382 }
4383 
4384 // Create cast instructions for converting LLVM value \p Src to LLVM type \p
4385 // DstTy. \p Src has the same size as \p DstTy. Both are single value types
4386 // but could be scalar or vectors of different lengths, and either can be
4387 // pointer.
4388 // There are 4 cases:
4389 // 1. non-pointer -> non-pointer : needs 1 bitcast
4390 // 2. pointer -> pointer : needs 1 bitcast or addrspacecast
4391 // 3. pointer -> non-pointer
4392 // a) pointer -> intptr_t : needs 1 ptrtoint
4393 // b) pointer -> non-intptr_t : needs 1 ptrtoint then 1 bitcast
4394 // 4. non-pointer -> pointer
4395 // a) intptr_t -> pointer : needs 1 inttoptr
4396 // b) non-intptr_t -> pointer : needs 1 bitcast then 1 inttoptr
4397 // Note: for cases 3b and 4b two casts are required since LLVM casts do not
4398 // allow casting directly between pointer types and non-integer non-pointer
4399 // types.
4401  const llvm::DataLayout &DL,
4402  Value *Src, llvm::Type *DstTy,
4403  StringRef Name = "") {
4404  auto SrcTy = Src->getType();
4405 
4406  // Case 1.
4407  if (!SrcTy->isPointerTy() && !DstTy->isPointerTy())
4408  return Builder.CreateBitCast(Src, DstTy, Name);
4409 
4410  // Case 2.
4411  if (SrcTy->isPointerTy() && DstTy->isPointerTy())
4412  return Builder.CreatePointerBitCastOrAddrSpaceCast(Src, DstTy, Name);
4413 
4414  // Case 3.
4415  if (SrcTy->isPointerTy() && !DstTy->isPointerTy()) {
4416  // Case 3b.
4417  if (!DstTy->isIntegerTy())
4418  Src = Builder.CreatePtrToInt(Src, DL.getIntPtrType(SrcTy));
4419  // Cases 3a and 3b.
4420  return Builder.CreateBitOrPointerCast(Src, DstTy, Name);
4421  }
4422 
4423  // Case 4b.
4424  if (!SrcTy->isIntegerTy())
4425  Src = Builder.CreateBitCast(Src, DL.getIntPtrType(DstTy));
4426  // Cases 4a and 4b.
4427  return Builder.CreateIntToPtr(Src, DstTy, Name);
4428 }
4429 
4430 Value *ScalarExprEmitter::VisitAsTypeExpr(AsTypeExpr *E) {
4431  Value *Src = CGF.EmitScalarExpr(E->getSrcExpr());
4432  llvm::Type *DstTy = ConvertType(E->getType());
4433 
4434  llvm::Type *SrcTy = Src->getType();
4435  unsigned NumElementsSrc = isa<llvm::VectorType>(SrcTy) ?
4436  cast<llvm::VectorType>(SrcTy)->getNumElements() : 0;
4437  unsigned NumElementsDst = isa<llvm::VectorType>(DstTy) ?
4438  cast<llvm::VectorType>(DstTy)->getNumElements() : 0;
4439 
4440  // Going from vec3 to non-vec3 is a special case and requires a shuffle
4441  // vector to get a vec4, then a bitcast if the target type is different.
4442  if (NumElementsSrc == 3 && NumElementsDst != 3) {
4443  Src = ConvertVec3AndVec4(Builder, CGF, Src, 4);
4444 
4445  if (!CGF.CGM.getCodeGenOpts().PreserveVec3Type) {
4446  Src = createCastsForTypeOfSameSize(Builder, CGF.CGM.getDataLayout(), Src,
4447  DstTy);
4448  }
4449 
4450  Src->setName("astype");
4451  return Src;
4452  }
4453 
4454  // Going from non-vec3 to vec3 is a special case and requires a bitcast
4455  // to vec4 if the original type is not vec4, then a shuffle vector to
4456  // get a vec3.
4457  if (NumElementsSrc != 3 && NumElementsDst == 3) {
4458  if (!CGF.CGM.getCodeGenOpts().PreserveVec3Type) {
4459  auto Vec4Ty = llvm::VectorType::get(DstTy->getVectorElementType(), 4);
4460  Src = createCastsForTypeOfSameSize(Builder, CGF.CGM.getDataLayout(), Src,
4461  Vec4Ty);
4462  }
4463 
4464  Src = ConvertVec3AndVec4(Builder, CGF, Src, 3);
4465  Src->setName("astype");
4466  return Src;
4467  }
4468 
4469  return Src = createCastsForTypeOfSameSize(Builder, CGF.CGM.getDataLayout(),
4470  Src, DstTy, "astype");
4471 }
4472 
4473 Value *ScalarExprEmitter::VisitAtomicExpr(AtomicExpr *E) {
4474  return CGF.EmitAtomicExpr(E).getScalarVal();
4475 }
4476 
4477 //===----------------------------------------------------------------------===//
4478 // Entry Point into this File
4479 //===----------------------------------------------------------------------===//
4480 
4481 /// Emit the computation of the specified expression of scalar type, ignoring
4482 /// the result.
4483 Value *CodeGenFunction::EmitScalarExpr(const Expr *E, bool IgnoreResultAssign) {
4484  assert(E && hasScalarEvaluationKind(E->getType()) &&
4485  "Invalid scalar expression to emit");
4486 
4487  return ScalarExprEmitter(*this, IgnoreResultAssign)
4488  .Visit(const_cast<Expr *>(E));
4489 }
4490 
4491 /// Emit a conversion from the specified type to the specified destination type,
4492 /// both of which are LLVM scalar types.
4494  QualType DstTy,
4495  SourceLocation Loc) {
4496  assert(hasScalarEvaluationKind(SrcTy) && hasScalarEvaluationKind(DstTy) &&
4497  "Invalid scalar expression to emit");
4498  return ScalarExprEmitter(*this).EmitScalarConversion(Src, SrcTy, DstTy, Loc);
4499 }
4500 
4501 /// Emit a conversion from the specified complex type to the specified
4502 /// destination type, where the destination type is an LLVM scalar type.
4504  QualType SrcTy,
4505  QualType DstTy,
4506  SourceLocation Loc) {
4507  assert(SrcTy->isAnyComplexType() && hasScalarEvaluationKind(DstTy) &&
4508  "Invalid complex -> scalar conversion");
4509  return ScalarExprEmitter(*this)
4510  .EmitComplexToScalarConversion(Src, SrcTy, DstTy, Loc);
4511 }
4512 
4513 
4516  bool isInc, bool isPre) {
4517  return ScalarExprEmitter(*this).EmitScalarPrePostIncDec(E, LV, isInc, isPre);
4518 }
4519 
4521  // object->isa or (*object).isa
4522  // Generate code as for: *(Class*)object
4523 
4524  Expr *BaseExpr = E->getBase();
4525  Address Addr = Address::invalid();
4526  if (BaseExpr->isRValue()) {
4527  Addr = Address(EmitScalarExpr(BaseExpr), getPointerAlign());
4528  } else {
4529  Addr = EmitLValue(BaseExpr).getAddress();
4530  }
4531 
4532  // Cast the address to Class*.
4533  Addr = Builder.CreateElementBitCast(Addr, ConvertType(E->getType()));
4534  return MakeAddrLValue(Addr, E->getType());
4535 }
4536 
4537 
4539  const CompoundAssignOperator *E) {
4540  ScalarExprEmitter Scalar(*this);
4541  Value *Result = nullptr;
4542  switch (E->getOpcode()) {
4543 #define COMPOUND_OP(Op) \
4544  case BO_##Op##Assign: \
4545  return Scalar.EmitCompoundAssignLValue(E, &ScalarExprEmitter::Emit##Op, \
4546  Result)
4547  COMPOUND_OP(Mul);
4548  COMPOUND_OP(Div);
4549  COMPOUND_OP(Rem);
4550  COMPOUND_OP(Add);
4551  COMPOUND_OP(Sub);
4552  COMPOUND_OP(Shl);
4553  COMPOUND_OP(Shr);
4554  COMPOUND_OP(And);
4555  COMPOUND_OP(Xor);
4556  COMPOUND_OP(Or);
4557 #undef COMPOUND_OP
4558 
4559  case BO_PtrMemD:
4560  case BO_PtrMemI:
4561  case BO_Mul:
4562  case BO_Div:
4563  case BO_Rem:
4564  case BO_Add:
4565  case BO_Sub:
4566  case BO_Shl:
4567  case BO_Shr:
4568  case BO_LT:
4569  case BO_GT:
4570  case BO_LE:
4571  case BO_GE:
4572  case BO_EQ:
4573  case BO_NE:
4574  case BO_Cmp:
4575  case BO_And:
4576  case BO_Xor:
4577  case BO_Or:
4578  case BO_LAnd:
4579  case BO_LOr:
4580  case BO_Assign:
4581  case BO_Comma:
4582  llvm_unreachable("Not valid compound assignment operators");
4583  }
4584 
4585  llvm_unreachable("Unhandled compound assignment operator");
4586 }
4587 
4589  ArrayRef<Value *> IdxList,
4590  bool SignedIndices,
4591  bool IsSubtraction,
4592  SourceLocation Loc,
4593  const Twine &Name) {
4594  Value *GEPVal = Builder.CreateInBoundsGEP(Ptr, IdxList, Name);
4595 
4596  // If the pointer overflow sanitizer isn't enabled, do nothing.
4597  if (!SanOpts.has(SanitizerKind::PointerOverflow))
4598  return GEPVal;
4599 
4600  // If the GEP has already been reduced to a constant, leave it be.
4601  if (isa<llvm::Constant>(GEPVal))
4602  return GEPVal;
4603 
4604  // Only check for overflows in the default address space.
4605  if (GEPVal->getType()->getPointerAddressSpace())
4606  return GEPVal;
4607 
4608  auto *GEP = cast<llvm::GEPOperator>(GEPVal);
4609  assert(GEP->isInBounds() && "Expected inbounds GEP");
4610 
4611  SanitizerScope SanScope(this);
4612  auto &VMContext = getLLVMContext();
4613  const auto &DL = CGM.getDataLayout();
4614  auto *IntPtrTy = DL.getIntPtrType(GEP->getPointerOperandType());
4615 
4616  // Grab references to the signed add/mul overflow intrinsics for intptr_t.
4617  auto *Zero = llvm::ConstantInt::getNullValue(IntPtrTy);
4618  auto *SAddIntrinsic =
4619  CGM.getIntrinsic(llvm::Intrinsic::sadd_with_overflow, IntPtrTy);
4620  auto *SMulIntrinsic =
4621  CGM.getIntrinsic(llvm::Intrinsic::smul_with_overflow, IntPtrTy);
4622 
4623  // The total (signed) byte offset for the GEP.
4624  llvm::Value *TotalOffset = nullptr;
4625  // The offset overflow flag - true if the total offset overflows.
4626  llvm::Value *OffsetOverflows = Builder.getFalse();
4627 
4628  /// Return the result of the given binary operation.
4629  auto eval = [&](BinaryOperator::Opcode Opcode, llvm::Value *LHS,
4630  llvm::Value *RHS) -> llvm::Value * {
4631  assert((Opcode == BO_Add || Opcode == BO_Mul) && "Can't eval binop");
4632 
4633  // If the operands are constants, return a constant result.
4634  if (auto *LHSCI = dyn_cast<llvm::ConstantInt>(LHS)) {
4635  if (auto *RHSCI = dyn_cast<llvm::ConstantInt>(RHS)) {
4636  llvm::APInt N;
4637  bool HasOverflow = mayHaveIntegerOverflow(LHSCI, RHSCI, Opcode,
4638  /*Signed=*/true, N);
4639  if (HasOverflow)
4640  OffsetOverflows = Builder.getTrue();
4641  return llvm::ConstantInt::get(VMContext, N);
4642  }
4643  }
4644 
4645  // Otherwise, compute the result with checked arithmetic.
4646  auto *ResultAndOverflow = Builder.CreateCall(
4647  (Opcode == BO_Add) ? SAddIntrinsic : SMulIntrinsic, {LHS, RHS});
4648  OffsetOverflows = Builder.CreateOr(
4649  Builder.CreateExtractValue(ResultAndOverflow, 1), OffsetOverflows);
4650  return Builder.CreateExtractValue(ResultAndOverflow, 0);
4651  };
4652 
4653  // Determine the total byte offset by looking at each GEP operand.
4654  for (auto GTI = llvm::gep_type_begin(GEP), GTE = llvm::gep_type_end(GEP);
4655  GTI != GTE; ++GTI) {
4656  llvm::Value *LocalOffset;
4657  auto *Index = GTI.getOperand();
4658  // Compute the local offset contributed by this indexing step:
4659  if (auto *STy = GTI.getStructTypeOrNull()) {
4660  // For struct indexing, the local offset is the byte position of the
4661  // specified field.
4662  unsigned FieldNo = cast<llvm::ConstantInt>(Index)->getZExtValue();
4663  LocalOffset = llvm::ConstantInt::get(
4664  IntPtrTy, DL.getStructLayout(STy)->getElementOffset(FieldNo));
4665  } else {
4666  // Otherwise this is array-like indexing. The local offset is the index
4667  // multiplied by the element size.
4668  auto *ElementSize = llvm::ConstantInt::get(
4669  IntPtrTy, DL.getTypeAllocSize(GTI.getIndexedType()));
4670  auto *IndexS = Builder.CreateIntCast(Index, IntPtrTy, /*isSigned=*/true);
4671  LocalOffset = eval(BO_Mul, ElementSize, IndexS);
4672  }
4673 
4674  // If this is the first offset, set it as the total offset. Otherwise, add
4675  // the local offset into the running total.
4676  if (!TotalOffset || TotalOffset == Zero)
4677  TotalOffset = LocalOffset;
4678  else
4679  TotalOffset = eval(BO_Add, TotalOffset, LocalOffset);
4680  }
4681 
4682  // Common case: if the total offset is zero, don't emit a check.
4683  if (TotalOffset == Zero)
4684  return GEPVal;
4685 
4686  // Now that we've computed the total offset, add it to the base pointer (with
4687  // wrapping semantics).
4688  auto *IntPtr = Builder.CreatePtrToInt(GEP->getPointerOperand(), IntPtrTy);
4689  auto *ComputedGEP = Builder.CreateAdd(IntPtr, TotalOffset);
4690 
4691  // The GEP is valid if:
4692  // 1) The total offset doesn't overflow, and
4693  // 2) The sign of the difference between the computed address and the base
4694  // pointer matches the sign of the total offset.
4695  llvm::Value *ValidGEP;
4696  auto *NoOffsetOverflow = Builder.CreateNot(OffsetOverflows);
4697  if (SignedIndices) {
4698  auto *PosOrZeroValid = Builder.CreateICmpUGE(ComputedGEP, IntPtr);
4699  auto *PosOrZeroOffset = Builder.CreateICmpSGE(TotalOffset, Zero);
4700  llvm::Value *NegValid = Builder.CreateICmpULT(ComputedGEP, IntPtr);
4701  ValidGEP = Builder.CreateAnd(
4702  Builder.CreateSelect(PosOrZeroOffset, PosOrZeroValid, NegValid),
4703  NoOffsetOverflow);
4704  } else if (!SignedIndices && !IsSubtraction) {
4705  auto *PosOrZeroValid = Builder.CreateICmpUGE(ComputedGEP, IntPtr);
4706  ValidGEP = Builder.CreateAnd(PosOrZeroValid, NoOffsetOverflow);
4707  } else {
4708  auto *NegOrZeroValid = Builder.CreateICmpULE(ComputedGEP, IntPtr);
4709  ValidGEP = Builder.CreateAnd(NegOrZeroValid, NoOffsetOverflow);
4710  }
4711 
4712  llvm::Constant *StaticArgs[] = {EmitCheckSourceLocation(Loc)};
4713  // Pass the computed GEP to the runtime to avoid emitting poisoned arguments.
4714  llvm::Value *DynamicArgs[] = {IntPtr, ComputedGEP};
4715  EmitCheck(std::make_pair(ValidGEP, SanitizerKind::PointerOverflow),
4716  SanitizerHandler::PointerOverflow, StaticArgs, DynamicArgs);
4717 
4718  return GEPVal;
4719 }
const llvm::DataLayout & getDataLayout() const
const Expr * getSubExpr() const
Definition: Expr.h:933
llvm::Value * getArrayInitIndex()
Get the index of the current ArrayInitLoopExpr, if any.
const internal::VariadicAllOfMatcher< Type > type
Matches Types in the clang AST.
Defines the clang::ASTContext interface.
std::pair< RValue, llvm::Value * > EmitAtomicCompareExchange(LValue Obj, RValue Expected, RValue Desired, SourceLocation Loc, llvm::AtomicOrdering Success=llvm::AtomicOrdering::SequentiallyConsistent, llvm::AtomicOrdering Failure=llvm::AtomicOrdering::SequentiallyConsistent, bool IsWeak=false, AggValueSlot Slot=AggValueSlot::ignored())
Emit a compare-and-exchange op for atomic type.
Definition: CGAtomic.cpp:1979
The null pointer literal (C++11 [lex.nullptr])
Definition: ExprCXX.h:587
Expr * getChosenSubExpr() const
getChosenSubExpr - Return the subexpression chosen according to the condition.
Definition: Expr.h:4141
static APFixedPoint getMax(const FixedPointSemantics &Sema)
Definition: FixedPoint.cpp:114
llvm::Value * EmitARCStoreStrong(LValue lvalue, llvm::Value *value, bool resultIgnored)
Store into a strong object.
Definition: CGObjC.cpp:2300
bool getValue() const
Definition: ExprObjC.h:97
bool getValue() const
Definition: ExprCXX.h:2571
bool isFixedPointType() const
Return true if this is a fixed point type according to ISO/IEC JTC1 SC22 WG14 N1169.
Definition: Type.h:6657
llvm::Value * EmitARCReclaimReturnedObject(const Expr *e, bool allowUnsafeClaim)
Definition: CGObjC.cpp:2837
static BinOpInfo createBinOpInfoFromIncDec(const UnaryOperator *E, llvm::Value *InVal, bool IsInc)
VersionTuple getPlatformMinVersion() const
Retrieve the minimum desired version of the platform, to which the program should be compiled...
Definition: TargetInfo.h:1245
bool isSignedOverflowDefined() const
Definition: LangOptions.h:272
PointerType - C99 6.7.5.1 - Pointer Declarators.
Definition: Type.h:2554
QualType getPointeeType() const
Definition: Type.h:2567
A (possibly-)qualified type.
Definition: Type.h:643
uint64_t getValue() const
Definition: ExprCXX.h:2661
bool sanitizePerformTypeCheck() const
Whether any type-checking sanitizers are enabled.
Definition: CGExpr.cpp:645
llvm::Type * ConvertTypeForMem(QualType T)
void EmitBranchOnBoolExpr(const Expr *Cond, llvm::BasicBlock *TrueBlock, llvm::BasicBlock *FalseBlock, uint64_t TrueCount)
EmitBranchOnBoolExpr - Emit a branch on a boolean condition (e.g.
static Opcode getOpForCompoundAssignment(Opcode Opc)
Definition: Expr.h:3544
const CodeGenOptions & getCodeGenOpts() const
SourceLocation getExprLoc() const
Definition: Expr.h:3438
llvm::Value * EmitARCExtendBlockObject(const Expr *expr)
Definition: CGObjC.cpp:3273
bool isUnsignedIntegerOrEnumerationType() const
Determines whether this is an integer type that is unsigned or an enumeration types whose underlying ...
Definition: Type.cpp:1931
RValue EmitCoyieldExpr(const CoyieldExpr &E, AggValueSlot aggSlot=AggValueSlot::ignored(), bool ignoreResult=false)
llvm::Constant * EmitCheckTypeDescriptor(QualType T)
Emit a description of a type in a format suitable for passing to a runtime sanitizer handler...
Definition: CGExpr.cpp:2777
void enterFullExpression(const FullExpr *E)
Expr * getExpr(unsigned Index)
getExpr - Return the Expr at the specified index.
Definition: Expr.h:4009
unsigned getNumSubExprs() const
getNumSubExprs - Return the size of the SubExprs array.
Definition: Expr.h:4003
llvm::APSInt getValue() const
Definition: FixedPoint.h:110
A type trait used in the implementation of various C++11 and Library TR1 trait templates.
Definition: ExprCXX.h:2528
Expr * getResultExpr()
Return the result expression of this controlling expression.
Definition: Expr.h:5390
llvm::Constant * getMemberPointerConstant(const UnaryOperator *e)
CompoundStmt * getSubStmt()
Definition: Expr.h:3940
LValue EmitObjCIsaExpr(const ObjCIsaExpr *E)
const internal::ArgumentAdaptingMatcherFunc< internal::HasMatcher > has
Matches AST nodes that have child AST nodes that match the provided matcher.
const Expr * getInit(unsigned Init) const
Definition: Expr.h:4421
static llvm::Constant * getAsInt32(llvm::ConstantInt *C, llvm::Type *I32Ty)
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
Kind getKind() const
Definition: Type.h:2435
QualType getPointeeType() const
If this is a pointer, ObjC object pointer, or block pointer, this returns the respective pointee...
Definition: Type.cpp:505
CharUnits getBaseClassOffset(const CXXRecordDecl *Base) const
getBaseClassOffset - Get the offset, in chars, for the given base class.
Definition: RecordLayout.h:232
bool isRealFloatingType() const
Floating point categories.
Definition: Type.cpp:1968
The fixed point semantics work similarly to llvm::fltSemantics.
Definition: FixedPoint.h:33
Address GetAddressOfDerivedClass(Address Value, const CXXRecordDecl *Derived, CastExpr::path_const_iterator PathBegin, CastExpr::path_const_iterator PathEnd, bool NullCheckValue)
Definition: CGClass.cpp:375
Address EmitPointerWithAlignment(const Expr *Addr, LValueBaseInfo *BaseInfo=nullptr, TBAAAccessInfo *TBAAInfo=nullptr)
EmitPointerWithAlignment - Given an expression with a pointer type, emit the value and compute our be...
Definition: CGExpr.cpp:1036
Address EmitVAArg(VAArgExpr *VE, Address &VAListAddr)
Generate code to get an argument from the passed in pointer and update it accordingly.
Definition: CGCall.cpp:4567
Expr * getBase() const
Definition: Expr.h:2886
RValue EmitPseudoObjectRValue(const PseudoObjectExpr *e, AggValueSlot slot=AggValueSlot::ignored())
Definition: CGExpr.cpp:4981
llvm::APFloat getValue() const
Definition: Expr.h:1569
Represents the index of the current element of an array being initialized by an ArrayInitLoopExpr.
Definition: Expr.h:5046
bool isExtVectorType() const
Definition: Type.h:6447
bool isVirtual() const
Determines whether the base class is a virtual base class (or not).
Definition: DeclCXX.h:245
RValue EmitCoawaitExpr(const CoawaitExpr &E, AggValueSlot aggSlot=AggValueSlot::ignored(), bool ignoreResult=false)
Opcode getOpcode() const
Definition: Expr.h:3442
void EmitCheck(ArrayRef< std::pair< llvm::Value *, SanitizerMask >> Checked, SanitizerHandler Check, ArrayRef< llvm::Constant *> StaticArgs, ArrayRef< llvm::Value *> DynamicArgs)
Create a basic block that will either trap or call a handler function in the UBSan runtime with the p...
Definition: CGExpr.cpp:2991
ParenExpr - This represents a parethesized expression, e.g.
Definition: Expr.h:1966
QualType getNonReferenceType() const
If Type is a reference type (e.g., const int&), returns the type that the reference refers to ("const...
Definition: Type.h:6300
llvm::Value * LoadCXXThis()
LoadCXXThis - Load the value of &#39;this&#39;.
void EmitStoreThroughLValue(RValue Src, LValue Dst, bool isInit=false)
EmitStoreThroughLValue - Store the specified rvalue into the specified lvalue, where both are guarant...
Definition: CGExpr.cpp:1925
FPOptions getFPFeatures() const
Definition: Expr.h:3584
An Embarcadero array type trait, as used in the implementation of __array_rank and __array_extent...
Definition: ExprCXX.h:2616
const TargetInfo & getTargetInfo() const
Definition: ASTContext.h:693
SourceLocation getLocation() const
Definition: Expr.h:4308
Floating point control options.
Definition: LangOptions.h:307
llvm::IntegerType * Int8Ty
i8, i16, i32, and i64
Represents a prvalue temporary that is written into memory so that a reference can bind to it...
Definition: ExprCXX.h:4320
static Value * buildFMulAdd(llvm::BinaryOperator *MulOp, Value *Addend, const CodeGenFunction &CGF, CGBuilderTy &Builder, bool negMul, bool negAdd)
bool ConstantFoldsToSimpleInteger(const Expr *Cond, bool &Result, bool AllowLabels=false)
ConstantFoldsToSimpleInteger - If the specified expression does not fold to a constant, or if it does but contains a label, return false.
QualType getElementType() const
Definition: Type.h:2864
#define COMPOUND_OP(Op)
Expr * getIndexExpr(unsigned Idx)
Definition: Expr.h:2302
bool isUnsignedIntegerType() const
Return true if this is an integer type that is unsigned, according to C99 6.2.5p6 [which returns true...
Definition: Type.cpp:1915
ObjCIsaExpr - Represent X->isa and X.isa when X is an ObjC &#39;id&#39; type.
Definition: ExprObjC.h:1492
CompoundLiteralExpr - [C99 6.5.2.5].
Definition: Expr.h:3050
RAII object to set/unset CodeGenFunction::IsSanitizerScope.
const AstTypeMatcher< PointerType > pointerType
Matches pointer types, but does not match Objective-C object pointer types.
const internal::VariadicDynCastAllOfMatcher< Stmt, Expr > expr
Matches expressions.
const T * getAs() const
Member-template getAs<specific type>&#39;.
Definition: Type.h:6818
uint64_t getProfileCount(const Stmt *S)
Get the profiler&#39;s count for the given statement.
const llvm::fltSemantics & getHalfFormat() const
Definition: TargetInfo.h:574
llvm::Value * EmitBlockCopyAndAutorelease(llvm::Value *Block, QualType Ty)
Definition: CGObjC.cpp:3673
void EmitVariablyModifiedType(QualType Ty)
EmitVLASize - Capture all the sizes for the VLA expressions in the given variably-modified type and s...
llvm::Value * getPointer() const
Definition: Address.h:37
bool IsSanitizerScope
True if CodeGen currently emits code implementing sanitizer checks.
A C++ throw-expression (C++ [except.throw]).
Definition: ExprCXX.h:1044
Represents an expression – generally a full-expression – that introduces cleanups to be run at the ...
Definition: ExprCXX.h:3207
long i
Definition: xmmintrin.h:1456
llvm::Value * EmitObjCDictionaryLiteral(const ObjCDictionaryLiteral *E)
Definition: CGObjC.cpp:244
void EmitStoreThroughBitfieldLValue(RValue Src, LValue Dst, llvm::Value **Result=nullptr)
EmitStoreThroughBitfieldLValue - Store Src into Dst with same constraints as EmitStoreThroughLValue.
Definition: CGExpr.cpp:2022
void EmitBoundsCheck(const Expr *E, const Expr *Base, llvm::Value *Index, QualType IndexType, bool Accessed)
Emit a check that Base points into an array object, which we can access at index Index.
Definition: CGExpr.cpp:959
Represents a struct/union/class.
Definition: Decl.h:3619
const TargetInfo & getTarget() const
An object to manage conditionally-evaluated expressions.
llvm::Value * EmitCXXNewExpr(const CXXNewExpr *E)
Definition: CGExprCXX.cpp:1520
FieldDecl * getField() const
For a field offsetof node, returns the field.
Definition: Expr.h:2199
llvm::Value * EmitScalarPrePostIncDec(const UnaryOperator *E, LValue LV, bool isInc, bool isPre)
LValue EmitScalarCompoundAssignWithComplex(const CompoundAssignOperator *E, llvm::Value *&Result)
Represents a function call to one of __builtin_LINE(), __builtin_COLUMN(), __builtin_FUNCTION(), or __builtin_FILE().
Definition: Expr.h:4265
ShuffleVectorExpr - clang-specific builtin-in function __builtin_shufflevector.
Definition: Expr.h:3969
Address getAddress() const
Definition: CGValue.h:326
QualType getComputationResultType() const
Definition: Expr.h:3653
CodeGenFunction - This class organizes the per-function state that is used while generating LLVM code...
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:154
std::pair< LValue, llvm::Value * > EmitARCStoreAutoreleasing(const BinaryOperator *e)
Definition: CGObjC.cpp:3429
bool hasOneOf(SanitizerMask K) const
Check if one or more sanitizers are enabled.
Definition: Sanitizers.h:158
llvm::Value * EmitDynamicCast(Address V, const CXXDynamicCastExpr *DCE)
Definition: CGExprCXX.cpp:2144
SourceLocation getBeginLoc() const LLVM_READONLY
Definition: Stmt.cpp:263
bool isVolatileQualified() const
Definition: CGValue.h:257
Represents a member of a struct/union/class.
Definition: Decl.h:2605
An RAII object to set (and then clear) a mapping for an OpaqueValueExpr.
unsigned getArrayExprIndex() const
For an array element node, returns the index into the array of expressions.
Definition: Expr.h:2193
unsigned getIntegralBits() const
Return the number of integral bits represented by these semantics.
Definition: FixedPoint.h:55
GNUNullExpr - Implements the GNU __null extension, which is a name for a null pointer constant that h...
Definition: Expr.h:4180
bool isReferenceType() const
Definition: Type.h:6363
Expr * getSubExpr()
Definition: Expr.h:3175
ObjCArrayLiteral - used for objective-c array containers; as in: @["Hello", NSApp, [NSNumber numberWithInt:42]];.
Definition: ExprObjC.h:188
llvm::Value * EmitObjCBoxedExpr(const ObjCBoxedExpr *E)
EmitObjCBoxedExpr - This routine generates code to call the appropriate expression boxing method...
Definition: CGObjC.cpp:59
bool hadArrayRangeDesignator() const
Definition: Expr.h:4541
An r-value expression (a pr-value in the C++11 taxonomy) produces a temporary value.
Definition: Specifiers.h:124
static ApplyDebugLocation CreateArtificial(CodeGenFunction &CGF)
Apply TemporaryLocation if it is valid.
Definition: CGDebugInfo.h:728
bool isGLValue() const
Definition: Expr.h:261
Describes an C or C++ initializer list.
Definition: Expr.h:4373
BinaryOperatorKind
llvm::Value * EmitObjCStringLiteral(const ObjCStringLiteral *E)
Emits an instance of NSConstantString representing the object.
Definition: CGObjC.cpp:45
static APFixedPoint getMin(const FixedPointSemantics &Sema)
Definition: FixedPoint.cpp:122
Address CreateElementBitCast(Address Addr, llvm::Type *Ty, const llvm::Twine &Name="")
Cast the element type of the given address to a different type, preserving information like the align...
Definition: CGBuilder.h:156
CharUnits - This is an opaque type for sizes expressed in character units.
Definition: CharUnits.h:37
APValue Val
Val - This is the value the expression can be folded to.
Definition: Expr.h:582
bool isOne() const
isOne - Test whether the quantity equals one.
Definition: CharUnits.h:118
path_iterator path_begin()
Definition: Expr.h:3195
llvm::Value * EmitBlockLiteral(const BlockExpr *)
Emit block literal.
Definition: CGBlocks.cpp:900
A builtin binary operation expression such as "x + y" or "x <= y".
Definition: Expr.h:3407
virtual llvm::Value * EmitMemberPointerIsNotNull(CodeGenFunction &CGF, llvm::Value *MemPtr, const MemberPointerType *MPT)
Determine if a member pointer is non-null. Returns an i1.
Definition: CGCXXABI.cpp:90
static Value * tryEmitFMulAdd(const BinOpInfo &op, const CodeGenFunction &CGF, CGBuilderTy &Builder, bool isSub=false)
ObjCStringLiteral, used for Objective-C string literals i.e.
Definition: ExprObjC.h:50
static llvm::Constant * getMaskElt(llvm::ShuffleVectorInst *SVI, unsigned Idx, unsigned Off, llvm::Type *I32Ty)
Scope - A scope is a transient data structure that is used while parsing the program.
Definition: Scope.h:40
const Type * getTypePtr() const
Retrieves a pointer to the underlying (unqualified) type.
Definition: Type.h:6127
unsigned getScale() const
Definition: FixedPoint.h:45
field_iterator field_begin() const
Definition: Decl.cpp:4264
llvm::BasicBlock * createBasicBlock(const Twine &name="", llvm::Function *parent=nullptr, llvm::BasicBlock *before=nullptr)
createBasicBlock - Create an LLVM basic block.
llvm::Value * EmitARCRetainScalarExpr(const Expr *expr)
EmitARCRetainScalarExpr - Semantically equivalent to EmitARCRetainObject(e->getType(), EmitScalarExpr(e)), but making a best-effort attempt to peephole expressions that naturally produce retained objects.
Definition: CGObjC.cpp:3240
void EmitIgnoredExpr(const Expr *E)
EmitIgnoredExpr - Emit an expression in a context which ignores the result.
Definition: CGExpr.cpp:181
CastExpr - Base class for type casts, including both implicit casts (ImplicitCastExpr) and explicit c...
Definition: Expr.h:3123
Helper class for OffsetOfExpr.
Definition: Expr.h:2135
void ForceCleanup(std::initializer_list< llvm::Value **> ValuesToReload={})
Force the emission of cleanups now, instead of waiting until this object is destroyed.
RValue EmitAtomicExpr(AtomicExpr *E)
Definition: CGAtomic.cpp:745
static bool ContainsLabel(const Stmt *S, bool IgnoreCaseStmts=false)
ContainsLabel - Return true if the statement contains a label in it.
void incrementProfileCounter(const Stmt *S, llvm::Value *StepV=nullptr)
Increment the profiler&#39;s counter for the given statement by StepV.
uint64_t getCurrentProfileCount()
Get the profiler&#39;s current count.
QualType getReturnType() const
Definition: DeclObjC.h:322
A default argument (C++ [dcl.fct.default]).
Definition: ExprCXX.h:1106
static bool ShouldNullCheckClassCastValue(const CastExpr *Cast)
Checking the operand of a load. Must be suitably sized and aligned.
Expr * IgnoreImpCasts() LLVM_READONLY
Skip past any implicit casts which might surround this expression until reaching a fixed point...
Definition: Expr.cpp:2901
This object can be modified without requiring retains or releases.
Definition: Type.h:158
Represents the this expression in C++.
Definition: ExprCXX.h:1001
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:445
static bool isNullPointerArithmeticExtension(ASTContext &Ctx, Opcode Opc, Expr *LHS, Expr *RHS)
Definition: Expr.cpp:2072
const Expr * getExpr() const
Get the initialization expression that will be used.
Definition: ExprCXX.h:1211
#define HANDLEBINOP(OP)
llvm::Value * EmitLoadOfScalar(Address Addr, bool Volatile, QualType Ty, SourceLocation Loc, AlignmentSource Source=AlignmentSource::Type, bool isNontemporal=false)
EmitLoadOfScalar - Load a scalar value from an address, taking care to appropriately convert from the...
bool isHalfType() const
Definition: Type.h:6616
RValue EmitObjCMessageExpr(const ObjCMessageExpr *E, ReturnValueSlot Return=ReturnValueSlot())
Definition: CGObjC.cpp:484
bool isValid() const
Definition: Address.h:35
Sema - This implements semantic analysis and AST building for C.
Definition: Sema.h:328
bool isPromotableIntegerType() const
More type predicates useful for type checking/promotion.
Definition: Type.cpp:2542
static CharUnits One()
One - Construct a CharUnits quantity of one.
Definition: CharUnits.h:57
Represents a C++ pseudo-destructor (C++ [expr.pseudo]).
Definition: ExprCXX.h:2380
std::pair< llvm::Value *, llvm::Value * > ComplexPairTy
const TargetCodeGenInfo & getTargetCodeGenInfo()
QualType getComputationLHSType() const
Definition: Expr.h:3650
CastKind
CastKind - The kind of operation required for a conversion.
static std::pair< ScalarExprEmitter::ImplicitConversionCheckKind, std::pair< llvm::Value *, SanitizerMask > > EmitIntegerTruncationCheckHelper(Value *Src, QualType SrcType, Value *Dst, QualType DstType, CGBuilderTy &Builder)
UnaryExprOrTypeTraitExpr - expression with either a type or (unevaluated) expression operand...
Definition: Expr.h:2344
llvm::Constant * getNullPointer(llvm::PointerType *T, QualType QT)
Get target specific null pointer.
QuantityType getQuantity() const
getQuantity - Get the raw integer representation of this quantity.
Definition: CharUnits.h:178
ConstantExpr - An expression that occurs in a constant context and optionally the result of evaluatin...
Definition: Expr.h:948
Represents a call to the builtin function __builtin_va_arg.
Definition: Expr.h:4214
llvm::APSInt EvaluateKnownConstInt(const ASTContext &Ctx, SmallVectorImpl< PartialDiagnosticAt > *Diag=nullptr) const
EvaluateKnownConstInt - Call EvaluateAsRValue and return the folded integer.
unsigned Offset
Definition: Format.cpp:1711
ASTRecordLayout - This class contains layout information for one RecordDecl, which is a struct/union/...
Definition: RecordLayout.h:38
const llvm::fltSemantics & getLongDoubleFormat() const
Definition: TargetInfo.h:590
unsigned getValue() const
Definition: Expr.h:1536
llvm::Value * emitScalarConstant(const ConstantEmission &Constant, Expr *E)
Definition: CGExpr.cpp:1512
llvm::Value * EmitARCStoreWeak(Address addr, llvm::Value *value, bool ignored)
i8* @objc_storeWeak(i8** addr, i8* value) Returns value.
Definition: CGObjC.cpp:2406
Expr * getSrcExpr() const
getSrcExpr - Return the Expr to be converted.
Definition: Expr.h:5615
llvm::APSInt getShuffleMaskIdx(const ASTContext &Ctx, unsigned N) const
Definition: Expr.h:4020
An expression "T()" which creates a value-initialized rvalue of type T, which is a non-class type...
Definition: ExprCXX.h:1953
bool isEventT() const
Definition: Type.h:6520
Represent the declaration of a variable (in which case it is an lvalue) a function (in which case it ...
Definition: Decl.h:636
This represents one expression.
Definition: Expr.h:108
Allow any unmodeled side effect.
Definition: Expr.h:609
static Address invalid()
Definition: Address.h:34
CXXBaseSpecifier * getBase() const
For a base class node, returns the base specifier.
Definition: Expr.h:2209
Enters a new scope for capturing cleanups, all of which will be executed once the scope is exited...
llvm::Value * EmitComplexToScalarConversion(ComplexPairTy Src, QualType SrcTy, QualType DstTy, SourceLocation Loc)
Emit a conversion from the specified complex type to the specified destination type, where the destination type is an LLVM scalar type.
SourceLocation getExprLoc() const LLVM_READONLY
Definition: ExprObjC.h:1541
const CXXRecordDecl * getPointeeCXXRecordDecl() const
If this is a pointer or reference to a RecordType, return the CXXRecordDecl that the type refers to...
Definition: Type.cpp:1621
unsigned getPackLength() const
Retrieve the length of the parameter pack.
Definition: ExprCXX.h:4069
const T * castAs() const
Member-template castAs<specific type>.
Definition: Type.h:6883
static std::pair< ScalarExprEmitter::ImplicitConversionCheckKind, std::pair< llvm::Value *, SanitizerMask > > EmitIntegerSignChangeCheckHelper(Value *Src, QualType SrcType, Value *Dst, QualType DstType, CGBuilderTy &Builder)
#define V(N, I)
Definition: ASTContext.h:2912
BlockExpr - Adaptor class for mixing a BlockDecl with expressions.
Definition: Expr.h:5543
Address EmitCompoundStmt(const CompoundStmt &S, bool GetLast=false, AggValueSlot AVS=AggValueSlot::ignored())
EmitCompoundStmt - Emit a compound statement {..} node.
Definition: CGStmt.cpp:368
unsigned getNumInits() const
Definition: Expr.h:4403
bool isNullPtrType() const
Definition: Type.h:6635
void SetFPAccuracy(llvm::Value *Val, float Accuracy)
SetFPAccuracy - Set the minimum required accuracy of the given floating point operation, expressed as the maximum relative error in ulp.
Definition: CGExpr.cpp:4891
VlaSizePair getVLASize(const VariableArrayType *vla)
Returns an LLVM value that corresponds to the size, in non-variably-sized elements, of a variable length array type, plus that largest non-variably-sized element type.
field_iterator field_end() const
Definition: Decl.h:3813
ObjCDictionaryLiteral - AST node to represent objective-c dictionary literals; as in:"name" : NSUserN...
Definition: ExprObjC.h:304
llvm::Value * EmitToMemory(llvm::Value *Value, QualType Ty)
EmitToMemory - Change a scalar value from its value representation to its in-memory representation...
Definition: CGExpr.cpp:1689
bool isAnyComplexType() const
Definition: Type.h:6439
ObjCSelectorExpr used for @selector in Objective-C.
Definition: ExprObjC.h:454
TypeSourceInfo * getTypeSourceInfo() const
Definition: Expr.h:2281
Represents an expression that computes the length of a parameter pack.
Definition: ExprCXX.h:3992
AsTypeExpr - Clang builtin function __builtin_astype [OpenCL 6.2.4.2] This AST node provides support ...
Definition: Expr.h:5592
unsigned getFieldCount() const
getFieldCount - Get the number of fields in the layout.
Definition: RecordLayout.h:186
llvm::LLVMContext & getLLVMContext()
Kind getKind() const
Determine what kind of offsetof node this is.
Definition: Expr.h:2189
QualType getType() const
Definition: Expr.h:137
void EmitNullabilityCheck(LValue LHS, llvm::Value *RHS, SourceLocation Loc)
Given an assignment *LHS = RHS, emit a test that checks if RHS is nonnull, if LHS is marked _Nonnull...
Definition: CGDecl.cpp:723
An RAII object to record that we&#39;re evaluating a statement expression.
QualType getTypeOfArgument() const
Gets the argument type, or the type of the argument expression, whichever is appropriate.
Definition: Expr.h:2407
void EmitTypeCheck(TypeCheckKind TCK, SourceLocation Loc, llvm::Value *V, QualType Type, CharUnits Alignment=CharUnits::Zero(), SanitizerSet SkippedChecks=SanitizerSet(), llvm::Value *ArraySize=nullptr)
Emit a check that V is the address of storage of the appropriate size and alignment for an object of ...
Definition: CGExpr.cpp:652
An expression that sends a message to the given Objective-C object or class.
Definition: ExprObjC.h:950
FixedPointSemantics getCommonSemantics(const FixedPointSemantics &Other) const
Return the FixedPointSemantics that allows for calculating the full precision semantic that can preci...
Definition: FixedPoint.cpp:127
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:2018
Represents a GCC generic vector type.
Definition: Type.h:3185
bool isNullPointer() const
Definition: APValue.cpp:743
llvm::Value * EmitCastToVoidPtr(llvm::Value *value)
Emit a cast to void* in the appropriate address space.
Definition: CGExpr.cpp:49
ConstantEmission tryEmitAsConstant(DeclRefExpr *refExpr)
Try to emit a reference to the given value without producing it as an l-value.
Definition: CGExpr.cpp:1431
Represents a reference to a non-type template parameter that has been substituted with a template arg...
Definition: ExprCXX.h:4110
const OffsetOfNode & getComponent(unsigned Idx) const
Definition: Expr.h:2288
const TargetInfo & getTarget() const
const Expr * getSubExpr() const
Definition: Expr.h:1982
bool getValue() const
Definition: ExprCXX.h:561
The l-value was considered opaque, so the alignment was determined from a type.
RecordDecl * getDecl() const
Definition: Type.h:4433
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:749
uint64_t getFieldOffset(unsigned FieldNo) const
getFieldOffset - Get the offset of the given field index, in bits.
Definition: RecordLayout.h:190
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...
There is no lifetime qualification on this type.
Definition: Type.h:154
bool getValue() const
Definition: ExprCXX.h:3885
A C++ dynamic_cast expression (C++ [expr.dynamic.cast]).
Definition: ExprCXX.h:349
OpaqueValueExpr - An expression referring to an opaque object of a fixed type and value class...
Definition: Expr.h:1047
Address CreateBitCast(Address Addr, llvm::Type *Ty, const llvm::Twine &Name="")
Definition: CGBuilder.h:141
ConvertVectorExpr - Clang builtin function __builtin_convertvector This AST node provides support for...
Definition: Expr.h:4037
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:67
#define false
Definition: stdbool.h:17
Assigning into this object requires the old value to be released and the new value to be retained...
Definition: Type.h:165
Kind
A field in a dependent type, known only by its name.
Definition: Expr.h:2144
PseudoObjectExpr - An expression which accesses a pseudo-object l-value.
Definition: Expr.h:5665
Encodes a location in the source.
void EnsureInsertPoint()
EnsureInsertPoint - Ensure that an insertion point is defined so that emitted IR has a place to go...
llvm::Value * EmitObjCArrayLiteral(const ObjCArrayLiteral *E)
Definition: CGObjC.cpp:240
std::pair< LValue, llvm::Value * > EmitARCStoreUnsafeUnretained(const BinaryOperator *e, bool ignored)
Definition: CGObjC.cpp:3379
bool mayBeNotDynamicClass() const
Returns true if it is not a class or if the class might not be dynamic.
Definition: Type.cpp:96
LangAS getAddressSpace() const
Return the address space of this type.
Definition: Type.h:6243
bool allowFPContractAcrossStatement() const
Definition: LangOptions.h:327
unsigned getOpenMPDefaultSimdAlign(QualType T) const
Get default simd alignment of the specified complete type in bits.
Expr * getSubExpr() const
Definition: Expr.h:2048
llvm::Value * EvaluateExprAsBool(const Expr *E)
EvaluateExprAsBool - Perform the usual unary conversions on the specified expression and compare the ...
Definition: CGExpr.cpp:163
LValue EmitCheckedLValue(const Expr *E, TypeCheckKind TCK)
Same as EmitLValue but additionally we generate checking code to guard against undefined behavior...
Definition: CGExpr.cpp:1207
bool isVariablyModifiedType() const
Whether this type is a variably-modified type (C99 6.7.5).
Definition: Type.h:2109
llvm::Value * EmitFromMemory(llvm::Value *Value, QualType Ty)
EmitFromMemory - Change a scalar value from its memory representation to its value representation...
Definition: CGExpr.cpp:1703
CastKind getCastKind() const
Definition: Expr.h:3169
Represents a new-expression for memory allocation and constructor calls, e.g: "new CXXNewExpr(foo)"...
Definition: ExprCXX.h:2000
QualType getElementType() const
Definition: Type.h:3220
A scoped helper to set the current debug location to the specified location or preferred location of ...
Definition: CGDebugInfo.h:697
StmtVisitor - This class implements a simple visitor for Stmt subclasses.
Definition: StmtVisitor.h:182
bool canOverflow() const
Returns true if the unary operator can cause an overflow.
Definition: Expr.h:2061
CanQualType FloatTy
Definition: ASTContext.h:1026
SanitizerSet SanOpts
Sanitizers enabled for this function.
const ArrayType * getAsArrayType(QualType T) const
Type Query functions.
bool isSignedIntegerOrEnumerationType() const
Determines whether this is an integer type that is signed or an enumeration types whose underlying ty...
Definition: Type.cpp:1891
AtomicExpr - Variadic atomic builtins: __atomic_exchange, __atomic_fetch_*, __atomic_load, __atomic_store, and __atomic_compare_exchange_*, for the similarly-named C++11 instructions, and __c11 variants for <stdatomic.h>, and corresponding __opencl_atomic_* for OpenCL 2.0.
Definition: Expr.h:5799
UnaryExprOrTypeTrait getKind() const
Definition: Expr.h:2375
APValue EvaluateInContext(const ASTContext &Ctx, const Expr *DefaultExpr) const
Return the result of evaluating this SourceLocExpr in the specified (and possibly null) default argum...
Definition: Expr.cpp:2143
llvm::Constant * emitAbstract(const Expr *E, QualType T)
Emit the result of the given expression as an abstract constant, asserting that it succeeded...
ObjCProtocolExpr used for protocol expression in Objective-C.
Definition: ExprObjC.h:503
TypeCheckKind
Situations in which we might emit a check for the suitability of a pointer or glvalue.
An aligned address.
Definition: Address.h:24
ImplicitCastExpr - Allows us to explicitly represent implicit type conversions, which have no direct ...
Definition: Expr.h:3247
Address EmitArrayToPointerDecay(const Expr *Array, LValueBaseInfo *BaseInfo=nullptr, TBAAAccessInfo *TBAAInfo=nullptr)
Definition: CGExpr.cpp:3300
An expression trait intrinsic.
Definition: ExprCXX.h:2686
const ObjCMethodDecl * getMethodDecl() const
Definition: ExprObjC.h:1356
bool isVectorType() const
Definition: Type.h:6443
Assigning into this object requires a lifetime extension.
Definition: Type.h:171
StmtExpr - This is the GNU Statement Expression extension: ({int X=4; X;}).
Definition: Expr.h:3924
bool isSaturated() const
Definition: FixedPoint.h:47
ObjCBoxedExpr - used for generalized expression boxing.
Definition: ExprObjC.h:124
virtual llvm::Constant * EmitNullMemberPointer(const MemberPointerType *MPT)
Create a null member pointer of the given type.
Definition: CGCXXABI.cpp:98
bool isArgumentType() const
Definition: Expr.h:2380
RValue EmitCallExpr(const CallExpr *E, ReturnValueSlot ReturnValue=ReturnValueSlot())
Definition: CGExpr.cpp:4403
FixedPointSemantics getFixedPointSemantics(QualType Ty) const
bool isCanonical() const
Definition: Type.h:6171
bool hasSameUnqualifiedType(QualType T1, QualType T2) const
Determine whether the given types are equivalent after cvr-qualifiers have been removed.
Definition: ASTContext.h:2320
static Value * createCastsForTypeOfSameSize(CGBuilderTy &Builder, const llvm::DataLayout &DL, Value *Src, llvm::Type *DstTy, StringRef Name="")
Defines the fixed point number interface.
SourceLocation getExprLoc() const LLVM_READONLY
getExprLoc - Return the preferred location for the arrow when diagnosing a problem with a generic exp...
Definition: Expr.cpp:215
__v16qu tmp
Definition: emmintrin.h:2133
const llvm::fltSemantics & getFloatTypeSemantics(QualType T) const
Return the APFloat &#39;semantics&#39; for the specified scalar floating point type.
Expr * getLHS() const
Definition: Expr.h:3447
CompoundAssignOperator - For compound assignments (e.g.
Definition: Expr.h:3627