clang  10.0.0svn
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(), AlignmentCI);
298  }
299 
300  /// EmitLoadOfLValue - Given an expression with complex type that represents a
301  /// value l-value, this method emits the address of the l-value, then loads
302  /// and returns the result.
303  Value *EmitLoadOfLValue(const Expr *E) {
304  Value *V = EmitLoadOfLValue(EmitCheckedLValue(E, CodeGenFunction::TCK_Load),
305  E->getExprLoc());
306 
307  EmitLValueAlignmentAssumption(E, V);
308  return V;
309  }
310 
311  /// EmitConversionToBool - Convert the specified expression value to a
312  /// boolean (i1) truth value. This is equivalent to "Val != 0".
313  Value *EmitConversionToBool(Value *Src, QualType DstTy);
314 
315  /// Emit a check that a conversion from a floating-point type does not
316  /// overflow.
317  void EmitFloatConversionCheck(Value *OrigSrc, QualType OrigSrcType,
318  Value *Src, QualType SrcType, QualType DstType,
319  llvm::Type *DstTy, SourceLocation Loc);
320 
321  /// Known implicit conversion check kinds.
322  /// Keep in sync with the enum of the same name in ubsan_handlers.h
323  enum ImplicitConversionCheckKind : unsigned char {
324  ICCK_IntegerTruncation = 0, // Legacy, was only used by clang 7.
325  ICCK_UnsignedIntegerTruncation = 1,
326  ICCK_SignedIntegerTruncation = 2,
327  ICCK_IntegerSignChange = 3,
328  ICCK_SignedIntegerTruncationOrSignChange = 4,
329  };
330 
331  /// Emit a check that an [implicit] truncation of an integer does not
332  /// discard any bits. It is not UB, so we use the value after truncation.
333  void EmitIntegerTruncationCheck(Value *Src, QualType SrcType, Value *Dst,
334  QualType DstType, SourceLocation Loc);
335 
336  /// Emit a check that an [implicit] conversion of an integer does not change
337  /// the sign of the value. It is not UB, so we use the value after conversion.
338  /// NOTE: Src and Dst may be the exact same value! (point to the same thing)
339  void EmitIntegerSignChangeCheck(Value *Src, QualType SrcType, Value *Dst,
340  QualType DstType, SourceLocation Loc);
341 
342  /// Emit a conversion from the specified type to the specified destination
343  /// type, both of which are LLVM scalar types.
344  struct ScalarConversionOpts {
345  bool TreatBooleanAsSigned;
346  bool EmitImplicitIntegerTruncationChecks;
347  bool EmitImplicitIntegerSignChangeChecks;
348 
349  ScalarConversionOpts()
350  : TreatBooleanAsSigned(false),
351  EmitImplicitIntegerTruncationChecks(false),
352  EmitImplicitIntegerSignChangeChecks(false) {}
353 
354  ScalarConversionOpts(clang::SanitizerSet SanOpts)
355  : TreatBooleanAsSigned(false),
356  EmitImplicitIntegerTruncationChecks(
357  SanOpts.hasOneOf(SanitizerKind::ImplicitIntegerTruncation)),
358  EmitImplicitIntegerSignChangeChecks(
359  SanOpts.has(SanitizerKind::ImplicitIntegerSignChange)) {}
360  };
361  Value *
362  EmitScalarConversion(Value *Src, QualType SrcTy, QualType DstTy,
363  SourceLocation Loc,
364  ScalarConversionOpts Opts = ScalarConversionOpts());
365 
366  /// Convert between either a fixed point and other fixed point or fixed point
367  /// and an integer.
368  Value *EmitFixedPointConversion(Value *Src, QualType SrcTy, QualType DstTy,
369  SourceLocation Loc);
370  Value *EmitFixedPointConversion(Value *Src, FixedPointSemantics &SrcFixedSema,
371  FixedPointSemantics &DstFixedSema,
372  SourceLocation Loc,
373  bool DstIsInteger = false);
374 
375  /// Emit a conversion from the specified complex type to the specified
376  /// destination type, where the destination type is an LLVM scalar type.
377  Value *EmitComplexToScalarConversion(CodeGenFunction::ComplexPairTy Src,
378  QualType SrcTy, QualType DstTy,
379  SourceLocation Loc);
380 
381  /// EmitNullValue - Emit a value that corresponds to null for the given type.
382  Value *EmitNullValue(QualType Ty);
383 
384  /// EmitFloatToBoolConversion - Perform an FP to boolean conversion.
385  Value *EmitFloatToBoolConversion(Value *V) {
386  // Compare against 0.0 for fp scalars.
387  llvm::Value *Zero = llvm::Constant::getNullValue(V->getType());
388  return Builder.CreateFCmpUNE(V, Zero, "tobool");
389  }
390 
391  /// EmitPointerToBoolConversion - Perform a pointer to boolean conversion.
392  Value *EmitPointerToBoolConversion(Value *V, QualType QT) {
393  Value *Zero = CGF.CGM.getNullPointer(cast<llvm::PointerType>(V->getType()), QT);
394 
395  return Builder.CreateICmpNE(V, Zero, "tobool");
396  }
397 
398  Value *EmitIntToBoolConversion(Value *V) {
399  // Because of the type rules of C, we often end up computing a
400  // logical value, then zero extending it to int, then wanting it
401  // as a logical value again. Optimize this common case.
402  if (llvm::ZExtInst *ZI = dyn_cast<llvm::ZExtInst>(V)) {
403  if (ZI->getOperand(0)->getType() == Builder.getInt1Ty()) {
404  Value *Result = ZI->getOperand(0);
405  // If there aren't any more uses, zap the instruction to save space.
406  // Note that there can be more uses, for example if this
407  // is the result of an assignment.
408  if (ZI->use_empty())
409  ZI->eraseFromParent();
410  return Result;
411  }
412  }
413 
414  return Builder.CreateIsNotNull(V, "tobool");
415  }
416 
417  //===--------------------------------------------------------------------===//
418  // Visitor Methods
419  //===--------------------------------------------------------------------===//
420 
421  Value *Visit(Expr *E) {
422  ApplyDebugLocation DL(CGF, E);
424  }
425 
426  Value *VisitStmt(Stmt *S) {
427  S->dump(CGF.getContext().getSourceManager());
428  llvm_unreachable("Stmt can't have complex result type!");
429  }
430  Value *VisitExpr(Expr *S);
431 
432  Value *VisitConstantExpr(ConstantExpr *E) {
433  return Visit(E->getSubExpr());
434  }
435  Value *VisitParenExpr(ParenExpr *PE) {
436  return Visit(PE->getSubExpr());
437  }
438  Value *VisitSubstNonTypeTemplateParmExpr(SubstNonTypeTemplateParmExpr *E) {
439  return Visit(E->getReplacement());
440  }
441  Value *VisitGenericSelectionExpr(GenericSelectionExpr *GE) {
442  return Visit(GE->getResultExpr());
443  }
444  Value *VisitCoawaitExpr(CoawaitExpr *S) {
445  return CGF.EmitCoawaitExpr(*S).getScalarVal();
446  }
447  Value *VisitCoyieldExpr(CoyieldExpr *S) {
448  return CGF.EmitCoyieldExpr(*S).getScalarVal();
449  }
450  Value *VisitUnaryCoawait(const UnaryOperator *E) {
451  return Visit(E->getSubExpr());
452  }
453 
454  // Leaves.
455  Value *VisitIntegerLiteral(const IntegerLiteral *E) {
456  return Builder.getInt(E->getValue());
457  }
458  Value *VisitFixedPointLiteral(const FixedPointLiteral *E) {
459  return Builder.getInt(E->getValue());
460  }
461  Value *VisitFloatingLiteral(const FloatingLiteral *E) {
462  return llvm::ConstantFP::get(VMContext, E->getValue());
463  }
464  Value *VisitCharacterLiteral(const CharacterLiteral *E) {
465  return llvm::ConstantInt::get(ConvertType(E->getType()), E->getValue());
466  }
467  Value *VisitObjCBoolLiteralExpr(const ObjCBoolLiteralExpr *E) {
468  return llvm::ConstantInt::get(ConvertType(E->getType()), E->getValue());
469  }
470  Value *VisitCXXBoolLiteralExpr(const CXXBoolLiteralExpr *E) {
471  return llvm::ConstantInt::get(ConvertType(E->getType()), E->getValue());
472  }
473  Value *VisitCXXScalarValueInitExpr(const CXXScalarValueInitExpr *E) {
474  return EmitNullValue(E->getType());
475  }
476  Value *VisitGNUNullExpr(const GNUNullExpr *E) {
477  return EmitNullValue(E->getType());
478  }
479  Value *VisitOffsetOfExpr(OffsetOfExpr *E);
480  Value *VisitUnaryExprOrTypeTraitExpr(const UnaryExprOrTypeTraitExpr *E);
481  Value *VisitAddrLabelExpr(const AddrLabelExpr *E) {
482  llvm::Value *V = CGF.GetAddrOfLabel(E->getLabel());
483  return Builder.CreateBitCast(V, ConvertType(E->getType()));
484  }
485 
486  Value *VisitSizeOfPackExpr(SizeOfPackExpr *E) {
487  return llvm::ConstantInt::get(ConvertType(E->getType()),E->getPackLength());
488  }
489 
490  Value *VisitPseudoObjectExpr(PseudoObjectExpr *E) {
491  return CGF.EmitPseudoObjectRValue(E).getScalarVal();
492  }
493 
494  Value *VisitOpaqueValueExpr(OpaqueValueExpr *E) {
495  if (E->isGLValue())
496  return EmitLoadOfLValue(CGF.getOrCreateOpaqueLValueMapping(E),
497  E->getExprLoc());
498 
499  // Otherwise, assume the mapping is the scalar directly.
501  }
502 
503  // l-values.
504  Value *VisitDeclRefExpr(DeclRefExpr *E) {
506  return CGF.emitScalarConstant(Constant, E);
507  return EmitLoadOfLValue(E);
508  }
509 
510  Value *VisitObjCSelectorExpr(ObjCSelectorExpr *E) {
511  return CGF.EmitObjCSelectorExpr(E);
512  }
513  Value *VisitObjCProtocolExpr(ObjCProtocolExpr *E) {
514  return CGF.EmitObjCProtocolExpr(E);
515  }
516  Value *VisitObjCIvarRefExpr(ObjCIvarRefExpr *E) {
517  return EmitLoadOfLValue(E);
518  }
519  Value *VisitObjCMessageExpr(ObjCMessageExpr *E) {
520  if (E->getMethodDecl() &&
522  return EmitLoadOfLValue(E);
523  return CGF.EmitObjCMessageExpr(E).getScalarVal();
524  }
525 
526  Value *VisitObjCIsaExpr(ObjCIsaExpr *E) {
527  LValue LV = CGF.EmitObjCIsaExpr(E);
528  Value *V = CGF.EmitLoadOfLValue(LV, E->getExprLoc()).getScalarVal();
529  return V;
530  }
531 
532  Value *VisitObjCAvailabilityCheckExpr(ObjCAvailabilityCheckExpr *E) {
533  VersionTuple Version = E->getVersion();
534 
535  // If we're checking for a platform older than our minimum deployment
536  // target, we can fold the check away.
537  if (Version <= CGF.CGM.getTarget().getPlatformMinVersion())
538  return llvm::ConstantInt::get(Builder.getInt1Ty(), 1);
539 
540  Optional<unsigned> Min = Version.getMinor(), SMin = Version.getSubminor();
541  llvm::Value *Args[] = {
542  llvm::ConstantInt::get(CGF.CGM.Int32Ty, Version.getMajor()),
543  llvm::ConstantInt::get(CGF.CGM.Int32Ty, Min ? *Min : 0),
544  llvm::ConstantInt::get(CGF.CGM.Int32Ty, SMin ? *SMin : 0),
545  };
546 
547  return CGF.EmitBuiltinAvailable(Args);
548  }
549 
550  Value *VisitArraySubscriptExpr(ArraySubscriptExpr *E);
551  Value *VisitShuffleVectorExpr(ShuffleVectorExpr *E);
552  Value *VisitConvertVectorExpr(ConvertVectorExpr *E);
553  Value *VisitMemberExpr(MemberExpr *E);
554  Value *VisitExtVectorElementExpr(Expr *E) { return EmitLoadOfLValue(E); }
555  Value *VisitCompoundLiteralExpr(CompoundLiteralExpr *E) {
556  return EmitLoadOfLValue(E);
557  }
558 
559  Value *VisitInitListExpr(InitListExpr *E);
560 
561  Value *VisitArrayInitIndexExpr(ArrayInitIndexExpr *E) {
562  assert(CGF.getArrayInitIndex() &&
563  "ArrayInitIndexExpr not inside an ArrayInitLoopExpr?");
564  return CGF.getArrayInitIndex();
565  }
566 
567  Value *VisitImplicitValueInitExpr(const ImplicitValueInitExpr *E) {
568  return EmitNullValue(E->getType());
569  }
570  Value *VisitExplicitCastExpr(ExplicitCastExpr *E) {
571  CGF.CGM.EmitExplicitCastExprType(E, &CGF);
572  return VisitCastExpr(E);
573  }
574  Value *VisitCastExpr(CastExpr *E);
575 
576  Value *VisitCallExpr(const CallExpr *E) {
577  if (E->getCallReturnType(CGF.getContext())->isReferenceType())
578  return EmitLoadOfLValue(E);
579 
580  Value *V = CGF.EmitCallExpr(E).getScalarVal();
581 
582  EmitLValueAlignmentAssumption(E, V);
583  return V;
584  }
585 
586  Value *VisitStmtExpr(const StmtExpr *E);
587 
588  // Unary Operators.
589  Value *VisitUnaryPostDec(const UnaryOperator *E) {
590  LValue LV = EmitLValue(E->getSubExpr());
591  return EmitScalarPrePostIncDec(E, LV, false, false);
592  }
593  Value *VisitUnaryPostInc(const UnaryOperator *E) {
594  LValue LV = EmitLValue(E->getSubExpr());
595  return EmitScalarPrePostIncDec(E, LV, true, false);
596  }
597  Value *VisitUnaryPreDec(const UnaryOperator *E) {
598  LValue LV = EmitLValue(E->getSubExpr());
599  return EmitScalarPrePostIncDec(E, LV, false, true);
600  }
601  Value *VisitUnaryPreInc(const UnaryOperator *E) {
602  LValue LV = EmitLValue(E->getSubExpr());
603  return EmitScalarPrePostIncDec(E, LV, true, true);
604  }
605 
606  llvm::Value *EmitIncDecConsiderOverflowBehavior(const UnaryOperator *E,
607  llvm::Value *InVal,
608  bool IsInc);
609 
610  llvm::Value *EmitScalarPrePostIncDec(const UnaryOperator *E, LValue LV,
611  bool isInc, bool isPre);
612 
613 
614  Value *VisitUnaryAddrOf(const UnaryOperator *E) {
615  if (isa<MemberPointerType>(E->getType())) // never sugared
616  return CGF.CGM.getMemberPointerConstant(E);
617 
618  return EmitLValue(E->getSubExpr()).getPointer();
619  }
620  Value *VisitUnaryDeref(const UnaryOperator *E) {
621  if (E->getType()->isVoidType())
622  return Visit(E->getSubExpr()); // the actual value should be unused
623  return EmitLoadOfLValue(E);
624  }
625  Value *VisitUnaryPlus(const UnaryOperator *E) {
626  // This differs from gcc, though, most likely due to a bug in gcc.
627  TestAndClearIgnoreResultAssign();
628  return Visit(E->getSubExpr());
629  }
630  Value *VisitUnaryMinus (const UnaryOperator *E);
631  Value *VisitUnaryNot (const UnaryOperator *E);
632  Value *VisitUnaryLNot (const UnaryOperator *E);
633  Value *VisitUnaryReal (const UnaryOperator *E);
634  Value *VisitUnaryImag (const UnaryOperator *E);
635  Value *VisitUnaryExtension(const UnaryOperator *E) {
636  return Visit(E->getSubExpr());
637  }
638 
639  // C++
640  Value *VisitMaterializeTemporaryExpr(const MaterializeTemporaryExpr *E) {
641  return EmitLoadOfLValue(E);
642  }
643  Value *VisitSourceLocExpr(SourceLocExpr *SLE) {
644  auto &Ctx = CGF.getContext();
645  APValue Evaluated =
647  return ConstantEmitter(CGF.CGM, &CGF)
648  .emitAbstract(SLE->getLocation(), Evaluated, SLE->getType());
649  }
650 
651  Value *VisitCXXDefaultArgExpr(CXXDefaultArgExpr *DAE) {
653  return Visit(DAE->getExpr());
654  }
655  Value *VisitCXXDefaultInitExpr(CXXDefaultInitExpr *DIE) {
657  return Visit(DIE->getExpr());
658  }
659  Value *VisitCXXThisExpr(CXXThisExpr *TE) {
660  return CGF.LoadCXXThis();
661  }
662 
663  Value *VisitExprWithCleanups(ExprWithCleanups *E);
664  Value *VisitCXXNewExpr(const CXXNewExpr *E) {
665  return CGF.EmitCXXNewExpr(E);
666  }
667  Value *VisitCXXDeleteExpr(const CXXDeleteExpr *E) {
668  CGF.EmitCXXDeleteExpr(E);
669  return nullptr;
670  }
671 
672  Value *VisitTypeTraitExpr(const TypeTraitExpr *E) {
673  return llvm::ConstantInt::get(ConvertType(E->getType()), E->getValue());
674  }
675 
676  Value *VisitConceptSpecializationExpr(const ConceptSpecializationExpr *E) {
677  return Builder.getInt1(E->isSatisfied());
678  }
679 
680  Value *VisitArrayTypeTraitExpr(const ArrayTypeTraitExpr *E) {
681  return llvm::ConstantInt::get(Builder.getInt32Ty(), E->getValue());
682  }
683 
684  Value *VisitExpressionTraitExpr(const ExpressionTraitExpr *E) {
685  return llvm::ConstantInt::get(Builder.getInt1Ty(), E->getValue());
686  }
687 
688  Value *VisitCXXPseudoDestructorExpr(const CXXPseudoDestructorExpr *E) {
689  // C++ [expr.pseudo]p1:
690  // The result shall only be used as the operand for the function call
691  // operator (), and the result of such a call has type void. The only
692  // effect is the evaluation of the postfix-expression before the dot or
693  // arrow.
694  CGF.EmitScalarExpr(E->getBase());
695  return nullptr;
696  }
697 
698  Value *VisitCXXNullPtrLiteralExpr(const CXXNullPtrLiteralExpr *E) {
699  return EmitNullValue(E->getType());
700  }
701 
702  Value *VisitCXXThrowExpr(const CXXThrowExpr *E) {
703  CGF.EmitCXXThrowExpr(E);
704  return nullptr;
705  }
706 
707  Value *VisitCXXNoexceptExpr(const CXXNoexceptExpr *E) {
708  return Builder.getInt1(E->getValue());
709  }
710 
711  // Binary Operators.
712  Value *EmitMul(const BinOpInfo &Ops) {
713  if (Ops.Ty->isSignedIntegerOrEnumerationType()) {
714  switch (CGF.getLangOpts().getSignedOverflowBehavior()) {
716  return Builder.CreateMul(Ops.LHS, Ops.RHS, "mul");
718  if (!CGF.SanOpts.has(SanitizerKind::SignedIntegerOverflow))
719  return Builder.CreateNSWMul(Ops.LHS, Ops.RHS, "mul");
720  LLVM_FALLTHROUGH;
722  if (CanElideOverflowCheck(CGF.getContext(), Ops))
723  return Builder.CreateNSWMul(Ops.LHS, Ops.RHS, "mul");
724  return EmitOverflowCheckedBinOp(Ops);
725  }
726  }
727 
728  if (Ops.Ty->isUnsignedIntegerType() &&
729  CGF.SanOpts.has(SanitizerKind::UnsignedIntegerOverflow) &&
730  !CanElideOverflowCheck(CGF.getContext(), Ops))
731  return EmitOverflowCheckedBinOp(Ops);
732 
733  if (Ops.LHS->getType()->isFPOrFPVectorTy()) {
734  Value *V = Builder.CreateFMul(Ops.LHS, Ops.RHS, "mul");
735  return propagateFMFlags(V, Ops);
736  }
737  return Builder.CreateMul(Ops.LHS, Ops.RHS, "mul");
738  }
739  /// Create a binary op that checks for overflow.
740  /// Currently only supports +, - and *.
741  Value *EmitOverflowCheckedBinOp(const BinOpInfo &Ops);
742 
743  // Check for undefined division and modulus behaviors.
744  void EmitUndefinedBehaviorIntegerDivAndRemCheck(const BinOpInfo &Ops,
745  llvm::Value *Zero,bool isDiv);
746  // Common helper for getting how wide LHS of shift is.
747  static Value *GetWidthMinusOneValue(Value* LHS,Value* RHS);
748  Value *EmitDiv(const BinOpInfo &Ops);
749  Value *EmitRem(const BinOpInfo &Ops);
750  Value *EmitAdd(const BinOpInfo &Ops);
751  Value *EmitSub(const BinOpInfo &Ops);
752  Value *EmitShl(const BinOpInfo &Ops);
753  Value *EmitShr(const BinOpInfo &Ops);
754  Value *EmitAnd(const BinOpInfo &Ops) {
755  return Builder.CreateAnd(Ops.LHS, Ops.RHS, "and");
756  }
757  Value *EmitXor(const BinOpInfo &Ops) {
758  return Builder.CreateXor(Ops.LHS, Ops.RHS, "xor");
759  }
760  Value *EmitOr (const BinOpInfo &Ops) {
761  return Builder.CreateOr(Ops.LHS, Ops.RHS, "or");
762  }
763 
764  // Helper functions for fixed point binary operations.
765  Value *EmitFixedPointBinOp(const BinOpInfo &Ops);
766 
767  BinOpInfo EmitBinOps(const BinaryOperator *E);
768  LValue EmitCompoundAssignLValue(const CompoundAssignOperator *E,
769  Value *(ScalarExprEmitter::*F)(const BinOpInfo &),
770  Value *&Result);
771 
772  Value *EmitCompoundAssign(const CompoundAssignOperator *E,
773  Value *(ScalarExprEmitter::*F)(const BinOpInfo &));
774 
775  // Binary operators and binary compound assignment operators.
776 #define HANDLEBINOP(OP) \
777  Value *VisitBin ## OP(const BinaryOperator *E) { \
778  return Emit ## OP(EmitBinOps(E)); \
779  } \
780  Value *VisitBin ## OP ## Assign(const CompoundAssignOperator *E) { \
781  return EmitCompoundAssign(E, &ScalarExprEmitter::Emit ## OP); \
782  }
784  HANDLEBINOP(Div)
785  HANDLEBINOP(Rem)
791  HANDLEBINOP(Xor)
792  HANDLEBINOP(Or)
793 #undef HANDLEBINOP
794 
795  // Comparisons.
796  Value *EmitCompare(const BinaryOperator *E, llvm::CmpInst::Predicate UICmpOpc,
797  llvm::CmpInst::Predicate SICmpOpc,
798  llvm::CmpInst::Predicate FCmpOpc);
799 #define VISITCOMP(CODE, UI, SI, FP) \
800  Value *VisitBin##CODE(const BinaryOperator *E) { \
801  return EmitCompare(E, llvm::ICmpInst::UI, llvm::ICmpInst::SI, \
802  llvm::FCmpInst::FP); }
803  VISITCOMP(LT, ICMP_ULT, ICMP_SLT, FCMP_OLT)
804  VISITCOMP(GT, ICMP_UGT, ICMP_SGT, FCMP_OGT)
805  VISITCOMP(LE, ICMP_ULE, ICMP_SLE, FCMP_OLE)
806  VISITCOMP(GE, ICMP_UGE, ICMP_SGE, FCMP_OGE)
807  VISITCOMP(EQ, ICMP_EQ , ICMP_EQ , FCMP_OEQ)
808  VISITCOMP(NE, ICMP_NE , ICMP_NE , FCMP_UNE)
809 #undef VISITCOMP
810 
811  Value *VisitBinAssign (const BinaryOperator *E);
812 
813  Value *VisitBinLAnd (const BinaryOperator *E);
814  Value *VisitBinLOr (const BinaryOperator *E);
815  Value *VisitBinComma (const BinaryOperator *E);
816 
817  Value *VisitBinPtrMemD(const Expr *E) { return EmitLoadOfLValue(E); }
818  Value *VisitBinPtrMemI(const Expr *E) { return EmitLoadOfLValue(E); }
819 
820  Value *VisitCXXRewrittenBinaryOperator(CXXRewrittenBinaryOperator *E) {
821  return Visit(E->getSemanticForm());
822  }
823 
824  // Other Operators.
825  Value *VisitBlockExpr(const BlockExpr *BE);
826  Value *VisitAbstractConditionalOperator(const AbstractConditionalOperator *);
827  Value *VisitChooseExpr(ChooseExpr *CE);
828  Value *VisitVAArgExpr(VAArgExpr *VE);
829  Value *VisitObjCStringLiteral(const ObjCStringLiteral *E) {
830  return CGF.EmitObjCStringLiteral(E);
831  }
832  Value *VisitObjCBoxedExpr(ObjCBoxedExpr *E) {
833  return CGF.EmitObjCBoxedExpr(E);
834  }
835  Value *VisitObjCArrayLiteral(ObjCArrayLiteral *E) {
836  return CGF.EmitObjCArrayLiteral(E);
837  }
838  Value *VisitObjCDictionaryLiteral(ObjCDictionaryLiteral *E) {
839  return CGF.EmitObjCDictionaryLiteral(E);
840  }
841  Value *VisitAsTypeExpr(AsTypeExpr *CE);
842  Value *VisitAtomicExpr(AtomicExpr *AE);
843 };
844 } // end anonymous namespace.
845 
846 //===----------------------------------------------------------------------===//
847 // Utilities
848 //===----------------------------------------------------------------------===//
849 
850 /// EmitConversionToBool - Convert the specified expression value to a
851 /// boolean (i1) truth value. This is equivalent to "Val != 0".
852 Value *ScalarExprEmitter::EmitConversionToBool(Value *Src, QualType SrcType) {
853  assert(SrcType.isCanonical() && "EmitScalarConversion strips typedefs");
854 
855  if (SrcType->isRealFloatingType())
856  return EmitFloatToBoolConversion(Src);
857 
858  if (const MemberPointerType *MPT = dyn_cast<MemberPointerType>(SrcType))
859  return CGF.CGM.getCXXABI().EmitMemberPointerIsNotNull(CGF, Src, MPT);
860 
861  assert((SrcType->isIntegerType() || isa<llvm::PointerType>(Src->getType())) &&
862  "Unknown scalar type to convert");
863 
864  if (isa<llvm::IntegerType>(Src->getType()))
865  return EmitIntToBoolConversion(Src);
866 
867  assert(isa<llvm::PointerType>(Src->getType()));
868  return EmitPointerToBoolConversion(Src, SrcType);
869 }
870 
871 void ScalarExprEmitter::EmitFloatConversionCheck(
872  Value *OrigSrc, QualType OrigSrcType, Value *Src, QualType SrcType,
873  QualType DstType, llvm::Type *DstTy, SourceLocation Loc) {
874  assert(SrcType->isFloatingType() && "not a conversion from floating point");
875  if (!isa<llvm::IntegerType>(DstTy))
876  return;
877 
878  CodeGenFunction::SanitizerScope SanScope(&CGF);
879  using llvm::APFloat;
880  using llvm::APSInt;
881 
882  llvm::Value *Check = nullptr;
883  const llvm::fltSemantics &SrcSema =
884  CGF.getContext().getFloatTypeSemantics(OrigSrcType);
885 
886  // Floating-point to integer. This has undefined behavior if the source is
887  // +-Inf, NaN, or doesn't fit into the destination type (after truncation
888  // to an integer).
889  unsigned Width = CGF.getContext().getIntWidth(DstType);
890  bool Unsigned = DstType->isUnsignedIntegerOrEnumerationType();
891 
892  APSInt Min = APSInt::getMinValue(Width, Unsigned);
893  APFloat MinSrc(SrcSema, APFloat::uninitialized);
894  if (MinSrc.convertFromAPInt(Min, !Unsigned, APFloat::rmTowardZero) &
895  APFloat::opOverflow)
896  // Don't need an overflow check for lower bound. Just check for
897  // -Inf/NaN.
898  MinSrc = APFloat::getInf(SrcSema, true);
899  else
900  // Find the largest value which is too small to represent (before
901  // truncation toward zero).
902  MinSrc.subtract(APFloat(SrcSema, 1), APFloat::rmTowardNegative);
903 
904  APSInt Max = APSInt::getMaxValue(Width, Unsigned);
905  APFloat MaxSrc(SrcSema, APFloat::uninitialized);
906  if (MaxSrc.convertFromAPInt(Max, !Unsigned, APFloat::rmTowardZero) &
907  APFloat::opOverflow)
908  // Don't need an overflow check for upper bound. Just check for
909  // +Inf/NaN.
910  MaxSrc = APFloat::getInf(SrcSema, false);
911  else
912  // Find the smallest value which is too large to represent (before
913  // truncation toward zero).
914  MaxSrc.add(APFloat(SrcSema, 1), APFloat::rmTowardPositive);
915 
916  // If we're converting from __half, convert the range to float to match
917  // the type of src.
918  if (OrigSrcType->isHalfType()) {
919  const llvm::fltSemantics &Sema =
920  CGF.getContext().getFloatTypeSemantics(SrcType);
921  bool IsInexact;
922  MinSrc.convert(Sema, APFloat::rmTowardZero, &IsInexact);
923  MaxSrc.convert(Sema, APFloat::rmTowardZero, &IsInexact);
924  }
925 
926  llvm::Value *GE =
927  Builder.CreateFCmpOGT(Src, llvm::ConstantFP::get(VMContext, MinSrc));
928  llvm::Value *LE =
929  Builder.CreateFCmpOLT(Src, llvm::ConstantFP::get(VMContext, MaxSrc));
930  Check = Builder.CreateAnd(GE, LE);
931 
932  llvm::Constant *StaticArgs[] = {CGF.EmitCheckSourceLocation(Loc),
933  CGF.EmitCheckTypeDescriptor(OrigSrcType),
934  CGF.EmitCheckTypeDescriptor(DstType)};
935  CGF.EmitCheck(std::make_pair(Check, SanitizerKind::FloatCastOverflow),
936  SanitizerHandler::FloatCastOverflow, StaticArgs, OrigSrc);
937 }
938 
939 // Should be called within CodeGenFunction::SanitizerScope RAII scope.
940 // Returns 'i1 false' when the truncation Src -> Dst was lossy.
941 static std::pair<ScalarExprEmitter::ImplicitConversionCheckKind,
942  std::pair<llvm::Value *, SanitizerMask>>
944  QualType DstType, CGBuilderTy &Builder) {
945  llvm::Type *SrcTy = Src->getType();
946  llvm::Type *DstTy = Dst->getType();
947  (void)DstTy; // Only used in assert()
948 
949  // This should be truncation of integral types.
950  assert(Src != Dst);
951  assert(SrcTy->getScalarSizeInBits() > Dst->getType()->getScalarSizeInBits());
952  assert(isa<llvm::IntegerType>(SrcTy) && isa<llvm::IntegerType>(DstTy) &&
953  "non-integer llvm type");
954 
955  bool SrcSigned = SrcType->isSignedIntegerOrEnumerationType();
956  bool DstSigned = DstType->isSignedIntegerOrEnumerationType();
957 
958  // If both (src and dst) types are unsigned, then it's an unsigned truncation.
959  // Else, it is a signed truncation.
960  ScalarExprEmitter::ImplicitConversionCheckKind Kind;
961  SanitizerMask Mask;
962  if (!SrcSigned && !DstSigned) {
963  Kind = ScalarExprEmitter::ICCK_UnsignedIntegerTruncation;
964  Mask = SanitizerKind::ImplicitUnsignedIntegerTruncation;
965  } else {
966  Kind = ScalarExprEmitter::ICCK_SignedIntegerTruncation;
967  Mask = SanitizerKind::ImplicitSignedIntegerTruncation;
968  }
969 
970  llvm::Value *Check = nullptr;
971  // 1. Extend the truncated value back to the same width as the Src.
972  Check = Builder.CreateIntCast(Dst, SrcTy, DstSigned, "anyext");
973  // 2. Equality-compare with the original source value
974  Check = Builder.CreateICmpEQ(Check, Src, "truncheck");
975  // If the comparison result is 'i1 false', then the truncation was lossy.
976  return std::make_pair(Kind, std::make_pair(Check, Mask));
977 }
978 
979 void ScalarExprEmitter::EmitIntegerTruncationCheck(Value *Src, QualType SrcType,
980  Value *Dst, QualType DstType,
981  SourceLocation Loc) {
982  if (!CGF.SanOpts.hasOneOf(SanitizerKind::ImplicitIntegerTruncation))
983  return;
984 
985  // We only care about int->int conversions here.
986  // We ignore conversions to/from pointer and/or bool.
987  if (!(SrcType->isIntegerType() && DstType->isIntegerType()))
988  return;
989 
990  unsigned SrcBits = Src->getType()->getScalarSizeInBits();
991  unsigned DstBits = Dst->getType()->getScalarSizeInBits();
992  // This must be truncation. Else we do not care.
993  if (SrcBits <= DstBits)
994  return;
995 
996  assert(!DstType->isBooleanType() && "we should not get here with booleans.");
997 
998  // If the integer sign change sanitizer is enabled,
999  // and we are truncating from larger unsigned type to smaller signed type,
1000  // let that next sanitizer deal with it.
1001  bool SrcSigned = SrcType->isSignedIntegerOrEnumerationType();
1002  bool DstSigned = DstType->isSignedIntegerOrEnumerationType();
1003  if (CGF.SanOpts.has(SanitizerKind::ImplicitIntegerSignChange) &&
1004  (!SrcSigned && DstSigned))
1005  return;
1006 
1007  CodeGenFunction::SanitizerScope SanScope(&CGF);
1008 
1009  std::pair<ScalarExprEmitter::ImplicitConversionCheckKind,
1010  std::pair<llvm::Value *, SanitizerMask>>
1011  Check =
1012  EmitIntegerTruncationCheckHelper(Src, SrcType, Dst, DstType, Builder);
1013  // If the comparison result is 'i1 false', then the truncation was lossy.
1014 
1015  // Do we care about this type of truncation?
1016  if (!CGF.SanOpts.has(Check.second.second))
1017  return;
1018 
1019  llvm::Constant *StaticArgs[] = {
1020  CGF.EmitCheckSourceLocation(Loc), CGF.EmitCheckTypeDescriptor(SrcType),
1021  CGF.EmitCheckTypeDescriptor(DstType),
1022  llvm::ConstantInt::get(Builder.getInt8Ty(), Check.first)};
1023  CGF.EmitCheck(Check.second, SanitizerHandler::ImplicitConversion, StaticArgs,
1024  {Src, Dst});
1025 }
1026 
1027 // Should be called within CodeGenFunction::SanitizerScope RAII scope.
1028 // Returns 'i1 false' when the conversion Src -> Dst changed the sign.
1029 static std::pair<ScalarExprEmitter::ImplicitConversionCheckKind,
1030  std::pair<llvm::Value *, SanitizerMask>>
1032  QualType DstType, CGBuilderTy &Builder) {
1033  llvm::Type *SrcTy = Src->getType();
1034  llvm::Type *DstTy = Dst->getType();
1035 
1036  assert(isa<llvm::IntegerType>(SrcTy) && isa<llvm::IntegerType>(DstTy) &&
1037  "non-integer llvm type");
1038 
1039  bool SrcSigned = SrcType->isSignedIntegerOrEnumerationType();
1040  bool DstSigned = DstType->isSignedIntegerOrEnumerationType();
1041  (void)SrcSigned; // Only used in assert()
1042  (void)DstSigned; // Only used in assert()
1043  unsigned SrcBits = SrcTy->getScalarSizeInBits();
1044  unsigned DstBits = DstTy->getScalarSizeInBits();
1045  (void)SrcBits; // Only used in assert()
1046  (void)DstBits; // Only used in assert()
1047 
1048  assert(((SrcBits != DstBits) || (SrcSigned != DstSigned)) &&
1049  "either the widths should be different, or the signednesses.");
1050 
1051  // NOTE: zero value is considered to be non-negative.
1052  auto EmitIsNegativeTest = [&Builder](Value *V, QualType VType,
1053  const char *Name) -> Value * {
1054  // Is this value a signed type?
1055  bool VSigned = VType->isSignedIntegerOrEnumerationType();
1056  llvm::Type *VTy = V->getType();
1057  if (!VSigned) {
1058  // If the value is unsigned, then it is never negative.
1059  // FIXME: can we encounter non-scalar VTy here?
1060  return llvm::ConstantInt::getFalse(VTy->getContext());
1061  }
1062  // Get the zero of the same type with which we will be comparing.
1063  llvm::Constant *Zero = llvm::ConstantInt::get(VTy, 0);
1064  // %V.isnegative = icmp slt %V, 0
1065  // I.e is %V *strictly* less than zero, does it have negative value?
1066  return Builder.CreateICmp(llvm::ICmpInst::ICMP_SLT, V, Zero,
1067  llvm::Twine(Name) + "." + V->getName() +
1068  ".negativitycheck");
1069  };
1070 
1071  // 1. Was the old Value negative?
1072  llvm::Value *SrcIsNegative = EmitIsNegativeTest(Src, SrcType, "src");
1073  // 2. Is the new Value negative?
1074  llvm::Value *DstIsNegative = EmitIsNegativeTest(Dst, DstType, "dst");
1075  // 3. Now, was the 'negativity status' preserved during the conversion?
1076  // NOTE: conversion from negative to zero is considered to change the sign.
1077  // (We want to get 'false' when the conversion changed the sign)
1078  // So we should just equality-compare the negativity statuses.
1079  llvm::Value *Check = nullptr;
1080  Check = Builder.CreateICmpEQ(SrcIsNegative, DstIsNegative, "signchangecheck");
1081  // If the comparison result is 'false', then the conversion changed the sign.
1082  return std::make_pair(
1083  ScalarExprEmitter::ICCK_IntegerSignChange,
1084  std::make_pair(Check, SanitizerKind::ImplicitIntegerSignChange));
1085 }
1086 
1087 void ScalarExprEmitter::EmitIntegerSignChangeCheck(Value *Src, QualType SrcType,
1088  Value *Dst, QualType DstType,
1089  SourceLocation Loc) {
1090  if (!CGF.SanOpts.has(SanitizerKind::ImplicitIntegerSignChange))
1091  return;
1092 
1093  llvm::Type *SrcTy = Src->getType();
1094  llvm::Type *DstTy = Dst->getType();
1095 
1096  // We only care about int->int conversions here.
1097  // We ignore conversions to/from pointer and/or bool.
1098  if (!(SrcType->isIntegerType() && DstType->isIntegerType()))
1099  return;
1100 
1101  bool SrcSigned = SrcType->isSignedIntegerOrEnumerationType();
1102  bool DstSigned = DstType->isSignedIntegerOrEnumerationType();
1103  unsigned SrcBits = SrcTy->getScalarSizeInBits();
1104  unsigned DstBits = DstTy->getScalarSizeInBits();
1105 
1106  // Now, we do not need to emit the check in *all* of the cases.
1107  // We can avoid emitting it in some obvious cases where it would have been
1108  // dropped by the opt passes (instcombine) always anyways.
1109  // If it's a cast between effectively the same type, no check.
1110  // NOTE: this is *not* equivalent to checking the canonical types.
1111  if (SrcSigned == DstSigned && SrcBits == DstBits)
1112  return;
1113  // At least one of the values needs to have signed type.
1114  // If both are unsigned, then obviously, neither of them can be negative.
1115  if (!SrcSigned && !DstSigned)
1116  return;
1117  // If the conversion is to *larger* *signed* type, then no check is needed.
1118  // Because either sign-extension happens (so the sign will remain),
1119  // or zero-extension will happen (the sign bit will be zero.)
1120  if ((DstBits > SrcBits) && DstSigned)
1121  return;
1122  if (CGF.SanOpts.has(SanitizerKind::ImplicitSignedIntegerTruncation) &&
1123  (SrcBits > DstBits) && SrcSigned) {
1124  // If the signed integer truncation sanitizer is enabled,
1125  // and this is a truncation from signed type, then no check is needed.
1126  // Because here sign change check is interchangeable with truncation check.
1127  return;
1128  }
1129  // That's it. We can't rule out any more cases with the data we have.
1130 
1131  CodeGenFunction::SanitizerScope SanScope(&CGF);
1132 
1133  std::pair<ScalarExprEmitter::ImplicitConversionCheckKind,
1134  std::pair<llvm::Value *, SanitizerMask>>
1135  Check;
1136 
1137  // Each of these checks needs to return 'false' when an issue was detected.
1138  ImplicitConversionCheckKind CheckKind;
1140  // So we can 'and' all the checks together, and still get 'false',
1141  // if at least one of the checks detected an issue.
1142 
1143  Check = EmitIntegerSignChangeCheckHelper(Src, SrcType, Dst, DstType, Builder);
1144  CheckKind = Check.first;
1145  Checks.emplace_back(Check.second);
1146 
1147  if (CGF.SanOpts.has(SanitizerKind::ImplicitSignedIntegerTruncation) &&
1148  (SrcBits > DstBits) && !SrcSigned && DstSigned) {
1149  // If the signed integer truncation sanitizer was enabled,
1150  // and we are truncating from larger unsigned type to smaller signed type,
1151  // let's handle the case we skipped in that check.
1152  Check =
1153  EmitIntegerTruncationCheckHelper(Src, SrcType, Dst, DstType, Builder);
1154  CheckKind = ICCK_SignedIntegerTruncationOrSignChange;
1155  Checks.emplace_back(Check.second);
1156  // If the comparison result is 'i1 false', then the truncation was lossy.
1157  }
1158 
1159  llvm::Constant *StaticArgs[] = {
1160  CGF.EmitCheckSourceLocation(Loc), CGF.EmitCheckTypeDescriptor(SrcType),
1161  CGF.EmitCheckTypeDescriptor(DstType),
1162  llvm::ConstantInt::get(Builder.getInt8Ty(), CheckKind)};
1163  // EmitCheck() will 'and' all the checks together.
1164  CGF.EmitCheck(Checks, SanitizerHandler::ImplicitConversion, StaticArgs,
1165  {Src, Dst});
1166 }
1167 
1168 /// Emit a conversion from the specified type to the specified destination type,
1169 /// both of which are LLVM scalar types.
1170 Value *ScalarExprEmitter::EmitScalarConversion(Value *Src, QualType SrcType,
1171  QualType DstType,
1172  SourceLocation Loc,
1173  ScalarConversionOpts Opts) {
1174  // All conversions involving fixed point types should be handled by the
1175  // EmitFixedPoint family functions. This is done to prevent bloating up this
1176  // function more, and although fixed point numbers are represented by
1177  // integers, we do not want to follow any logic that assumes they should be
1178  // treated as integers.
1179  // TODO(leonardchan): When necessary, add another if statement checking for
1180  // conversions to fixed point types from other types.
1181  if (SrcType->isFixedPointType()) {
1182  if (DstType->isBooleanType())
1183  // It is important that we check this before checking if the dest type is
1184  // an integer because booleans are technically integer types.
1185  // We do not need to check the padding bit on unsigned types if unsigned
1186  // padding is enabled because overflow into this bit is undefined
1187  // behavior.
1188  return Builder.CreateIsNotNull(Src, "tobool");
1189  if (DstType->isFixedPointType() || DstType->isIntegerType())
1190  return EmitFixedPointConversion(Src, SrcType, DstType, Loc);
1191 
1192  llvm_unreachable(
1193  "Unhandled scalar conversion from a fixed point type to another type.");
1194  } else if (DstType->isFixedPointType()) {
1195  if (SrcType->isIntegerType())
1196  // This also includes converting booleans and enums to fixed point types.
1197  return EmitFixedPointConversion(Src, SrcType, DstType, Loc);
1198 
1199  llvm_unreachable(
1200  "Unhandled scalar conversion to a fixed point type from another type.");
1201  }
1202 
1203  QualType NoncanonicalSrcType = SrcType;
1204  QualType NoncanonicalDstType = DstType;
1205 
1206  SrcType = CGF.getContext().getCanonicalType(SrcType);
1207  DstType = CGF.getContext().getCanonicalType(DstType);
1208  if (SrcType == DstType) return Src;
1209 
1210  if (DstType->isVoidType()) return nullptr;
1211 
1212  llvm::Value *OrigSrc = Src;
1213  QualType OrigSrcType = SrcType;
1214  llvm::Type *SrcTy = Src->getType();
1215 
1216  // Handle conversions to bool first, they are special: comparisons against 0.
1217  if (DstType->isBooleanType())
1218  return EmitConversionToBool(Src, SrcType);
1219 
1220  llvm::Type *DstTy = ConvertType(DstType);
1221 
1222  // Cast from half through float if half isn't a native type.
1223  if (SrcType->isHalfType() && !CGF.getContext().getLangOpts().NativeHalfType) {
1224  // Cast to FP using the intrinsic if the half type itself isn't supported.
1225  if (DstTy->isFloatingPointTy()) {
1227  return Builder.CreateCall(
1228  CGF.CGM.getIntrinsic(llvm::Intrinsic::convert_from_fp16, DstTy),
1229  Src);
1230  } else {
1231  // Cast to other types through float, using either the intrinsic or FPExt,
1232  // depending on whether the half type itself is supported
1233  // (as opposed to operations on half, available with NativeHalfType).
1235  Src = Builder.CreateCall(
1236  CGF.CGM.getIntrinsic(llvm::Intrinsic::convert_from_fp16,
1237  CGF.CGM.FloatTy),
1238  Src);
1239  } else {
1240  Src = Builder.CreateFPExt(Src, CGF.CGM.FloatTy, "conv");
1241  }
1242  SrcType = CGF.getContext().FloatTy;
1243  SrcTy = CGF.FloatTy;
1244  }
1245  }
1246 
1247  // Ignore conversions like int -> uint.
1248  if (SrcTy == DstTy) {
1249  if (Opts.EmitImplicitIntegerSignChangeChecks)
1250  EmitIntegerSignChangeCheck(Src, NoncanonicalSrcType, Src,
1251  NoncanonicalDstType, Loc);
1252 
1253  return Src;
1254  }
1255 
1256  // Handle pointer conversions next: pointers can only be converted to/from
1257  // other pointers and integers. Check for pointer types in terms of LLVM, as
1258  // some native types (like Obj-C id) may map to a pointer type.
1259  if (auto DstPT = dyn_cast<llvm::PointerType>(DstTy)) {
1260  // The source value may be an integer, or a pointer.
1261  if (isa<llvm::PointerType>(SrcTy))
1262  return Builder.CreateBitCast(Src, DstTy, "conv");
1263 
1264  assert(SrcType->isIntegerType() && "Not ptr->ptr or int->ptr conversion?");
1265  // First, convert to the correct width so that we control the kind of
1266  // extension.
1267  llvm::Type *MiddleTy = CGF.CGM.getDataLayout().getIntPtrType(DstPT);
1268  bool InputSigned = SrcType->isSignedIntegerOrEnumerationType();
1269  llvm::Value* IntResult =
1270  Builder.CreateIntCast(Src, MiddleTy, InputSigned, "conv");
1271  // Then, cast to pointer.
1272  return Builder.CreateIntToPtr(IntResult, DstTy, "conv");
1273  }
1274 
1275  if (isa<llvm::PointerType>(SrcTy)) {
1276  // Must be an ptr to int cast.
1277  assert(isa<llvm::IntegerType>(DstTy) && "not ptr->int?");
1278  return Builder.CreatePtrToInt(Src, DstTy, "conv");
1279  }
1280 
1281  // A scalar can be splatted to an extended vector of the same element type
1282  if (DstType->isExtVectorType() && !SrcType->isVectorType()) {
1283  // Sema should add casts to make sure that the source expression's type is
1284  // the same as the vector's element type (sans qualifiers)
1285  assert(DstType->castAs<ExtVectorType>()->getElementType().getTypePtr() ==
1286  SrcType.getTypePtr() &&
1287  "Splatted expr doesn't match with vector element type?");
1288 
1289  // Splat the element across to all elements
1290  unsigned NumElements = DstTy->getVectorNumElements();
1291  return Builder.CreateVectorSplat(NumElements, Src, "splat");
1292  }
1293 
1294  if (isa<llvm::VectorType>(SrcTy) || isa<llvm::VectorType>(DstTy)) {
1295  // Allow bitcast from vector to integer/fp of the same size.
1296  unsigned SrcSize = SrcTy->getPrimitiveSizeInBits();
1297  unsigned DstSize = DstTy->getPrimitiveSizeInBits();
1298  if (SrcSize == DstSize)
1299  return Builder.CreateBitCast(Src, DstTy, "conv");
1300 
1301  // Conversions between vectors of different sizes are not allowed except
1302  // when vectors of half are involved. Operations on storage-only half
1303  // vectors require promoting half vector operands to float vectors and
1304  // truncating the result, which is either an int or float vector, to a
1305  // short or half vector.
1306 
1307  // Source and destination are both expected to be vectors.
1308  llvm::Type *SrcElementTy = SrcTy->getVectorElementType();
1309  llvm::Type *DstElementTy = DstTy->getVectorElementType();
1310  (void)DstElementTy;
1311 
1312  assert(((SrcElementTy->isIntegerTy() &&
1313  DstElementTy->isIntegerTy()) ||
1314  (SrcElementTy->isFloatingPointTy() &&
1315  DstElementTy->isFloatingPointTy())) &&
1316  "unexpected conversion between a floating-point vector and an "
1317  "integer vector");
1318 
1319  // Truncate an i32 vector to an i16 vector.
1320  if (SrcElementTy->isIntegerTy())
1321  return Builder.CreateIntCast(Src, DstTy, false, "conv");
1322 
1323  // Truncate a float vector to a half vector.
1324  if (SrcSize > DstSize)
1325  return Builder.CreateFPTrunc(Src, DstTy, "conv");
1326 
1327  // Promote a half vector to a float vector.
1328  return Builder.CreateFPExt(Src, DstTy, "conv");
1329  }
1330 
1331  // Finally, we have the arithmetic types: real int/float.
1332  Value *Res = nullptr;
1333  llvm::Type *ResTy = DstTy;
1334 
1335  // An overflowing conversion has undefined behavior if either the source type
1336  // or the destination type is a floating-point type. However, we consider the
1337  // range of representable values for all floating-point types to be
1338  // [-inf,+inf], so no overflow can ever happen when the destination type is a
1339  // floating-point type.
1340  if (CGF.SanOpts.has(SanitizerKind::FloatCastOverflow) &&
1341  OrigSrcType->isFloatingType())
1342  EmitFloatConversionCheck(OrigSrc, OrigSrcType, Src, SrcType, DstType, DstTy,
1343  Loc);
1344 
1345  // Cast to half through float if half isn't a native type.
1346  if (DstType->isHalfType() && !CGF.getContext().getLangOpts().NativeHalfType) {
1347  // Make sure we cast in a single step if from another FP type.
1348  if (SrcTy->isFloatingPointTy()) {
1349  // Use the intrinsic if the half type itself isn't supported
1350  // (as opposed to operations on half, available with NativeHalfType).
1352  return Builder.CreateCall(
1353  CGF.CGM.getIntrinsic(llvm::Intrinsic::convert_to_fp16, SrcTy), Src);
1354  // If the half type is supported, just use an fptrunc.
1355  return Builder.CreateFPTrunc(Src, DstTy);
1356  }
1357  DstTy = CGF.FloatTy;
1358  }
1359 
1360  if (isa<llvm::IntegerType>(SrcTy)) {
1361  bool InputSigned = SrcType->isSignedIntegerOrEnumerationType();
1362  if (SrcType->isBooleanType() && Opts.TreatBooleanAsSigned) {
1363  InputSigned = true;
1364  }
1365  if (isa<llvm::IntegerType>(DstTy))
1366  Res = Builder.CreateIntCast(Src, DstTy, InputSigned, "conv");
1367  else if (InputSigned)
1368  Res = Builder.CreateSIToFP(Src, DstTy, "conv");
1369  else
1370  Res = Builder.CreateUIToFP(Src, DstTy, "conv");
1371  } else if (isa<llvm::IntegerType>(DstTy)) {
1372  assert(SrcTy->isFloatingPointTy() && "Unknown real conversion");
1373  if (DstType->isSignedIntegerOrEnumerationType())
1374  Res = Builder.CreateFPToSI(Src, DstTy, "conv");
1375  else
1376  Res = Builder.CreateFPToUI(Src, DstTy, "conv");
1377  } else {
1378  assert(SrcTy->isFloatingPointTy() && DstTy->isFloatingPointTy() &&
1379  "Unknown real conversion");
1380  if (DstTy->getTypeID() < SrcTy->getTypeID())
1381  Res = Builder.CreateFPTrunc(Src, DstTy, "conv");
1382  else
1383  Res = Builder.CreateFPExt(Src, DstTy, "conv");
1384  }
1385 
1386  if (DstTy != ResTy) {
1388  assert(ResTy->isIntegerTy(16) && "Only half FP requires extra conversion");
1389  Res = Builder.CreateCall(
1390  CGF.CGM.getIntrinsic(llvm::Intrinsic::convert_to_fp16, CGF.CGM.FloatTy),
1391  Res);
1392  } else {
1393  Res = Builder.CreateFPTrunc(Res, ResTy, "conv");
1394  }
1395  }
1396 
1397  if (Opts.EmitImplicitIntegerTruncationChecks)
1398  EmitIntegerTruncationCheck(Src, NoncanonicalSrcType, Res,
1399  NoncanonicalDstType, Loc);
1400 
1401  if (Opts.EmitImplicitIntegerSignChangeChecks)
1402  EmitIntegerSignChangeCheck(Src, NoncanonicalSrcType, Res,
1403  NoncanonicalDstType, Loc);
1404 
1405  return Res;
1406 }
1407 
1408 Value *ScalarExprEmitter::EmitFixedPointConversion(Value *Src, QualType SrcTy,
1409  QualType DstTy,
1410  SourceLocation Loc) {
1411  FixedPointSemantics SrcFPSema =
1412  CGF.getContext().getFixedPointSemantics(SrcTy);
1413  FixedPointSemantics DstFPSema =
1414  CGF.getContext().getFixedPointSemantics(DstTy);
1415  return EmitFixedPointConversion(Src, SrcFPSema, DstFPSema, Loc,
1416  DstTy->isIntegerType());
1417 }
1418 
1419 Value *ScalarExprEmitter::EmitFixedPointConversion(
1420  Value *Src, FixedPointSemantics &SrcFPSema, FixedPointSemantics &DstFPSema,
1421  SourceLocation Loc, bool DstIsInteger) {
1422  using llvm::APInt;
1423  using llvm::ConstantInt;
1424  using llvm::Value;
1425 
1426  unsigned SrcWidth = SrcFPSema.getWidth();
1427  unsigned DstWidth = DstFPSema.getWidth();
1428  unsigned SrcScale = SrcFPSema.getScale();
1429  unsigned DstScale = DstFPSema.getScale();
1430  bool SrcIsSigned = SrcFPSema.isSigned();
1431  bool DstIsSigned = DstFPSema.isSigned();
1432 
1433  llvm::Type *DstIntTy = Builder.getIntNTy(DstWidth);
1434 
1435  Value *Result = Src;
1436  unsigned ResultWidth = SrcWidth;
1437 
1438  // Downscale.
1439  if (DstScale < SrcScale) {
1440  // When converting to integers, we round towards zero. For negative numbers,
1441  // right shifting rounds towards negative infinity. In this case, we can
1442  // just round up before shifting.
1443  if (DstIsInteger && SrcIsSigned) {
1444  Value *Zero = llvm::Constant::getNullValue(Result->getType());
1445  Value *IsNegative = Builder.CreateICmpSLT(Result, Zero);
1446  Value *LowBits = ConstantInt::get(
1447  CGF.getLLVMContext(), APInt::getLowBitsSet(ResultWidth, SrcScale));
1448  Value *Rounded = Builder.CreateAdd(Result, LowBits);
1449  Result = Builder.CreateSelect(IsNegative, Rounded, Result);
1450  }
1451 
1452  Result = SrcIsSigned
1453  ? Builder.CreateAShr(Result, SrcScale - DstScale, "downscale")
1454  : Builder.CreateLShr(Result, SrcScale - DstScale, "downscale");
1455  }
1456 
1457  if (!DstFPSema.isSaturated()) {
1458  // Resize.
1459  Result = Builder.CreateIntCast(Result, DstIntTy, SrcIsSigned, "resize");
1460 
1461  // Upscale.
1462  if (DstScale > SrcScale)
1463  Result = Builder.CreateShl(Result, DstScale - SrcScale, "upscale");
1464  } else {
1465  // Adjust the number of fractional bits.
1466  if (DstScale > SrcScale) {
1467  // Compare to DstWidth to prevent resizing twice.
1468  ResultWidth = std::max(SrcWidth + DstScale - SrcScale, DstWidth);
1469  llvm::Type *UpscaledTy = Builder.getIntNTy(ResultWidth);
1470  Result = Builder.CreateIntCast(Result, UpscaledTy, SrcIsSigned, "resize");
1471  Result = Builder.CreateShl(Result, DstScale - SrcScale, "upscale");
1472  }
1473 
1474  // Handle saturation.
1475  bool LessIntBits = DstFPSema.getIntegralBits() < SrcFPSema.getIntegralBits();
1476  if (LessIntBits) {
1477  Value *Max = ConstantInt::get(
1478  CGF.getLLVMContext(),
1479  APFixedPoint::getMax(DstFPSema).getValue().extOrTrunc(ResultWidth));
1480  Value *TooHigh = SrcIsSigned ? Builder.CreateICmpSGT(Result, Max)
1481  : Builder.CreateICmpUGT(Result, Max);
1482  Result = Builder.CreateSelect(TooHigh, Max, Result, "satmax");
1483  }
1484  // Cannot overflow min to dest type if src is unsigned since all fixed
1485  // point types can cover the unsigned min of 0.
1486  if (SrcIsSigned && (LessIntBits || !DstIsSigned)) {
1487  Value *Min = ConstantInt::get(
1488  CGF.getLLVMContext(),
1489  APFixedPoint::getMin(DstFPSema).getValue().extOrTrunc(ResultWidth));
1490  Value *TooLow = Builder.CreateICmpSLT(Result, Min);
1491  Result = Builder.CreateSelect(TooLow, Min, Result, "satmin");
1492  }
1493 
1494  // Resize the integer part to get the final destination size.
1495  if (ResultWidth != DstWidth)
1496  Result = Builder.CreateIntCast(Result, DstIntTy, SrcIsSigned, "resize");
1497  }
1498  return Result;
1499 }
1500 
1501 /// Emit a conversion from the specified complex type to the specified
1502 /// destination type, where the destination type is an LLVM scalar type.
1503 Value *ScalarExprEmitter::EmitComplexToScalarConversion(
1505  SourceLocation Loc) {
1506  // Get the source element type.
1507  SrcTy = SrcTy->castAs<ComplexType>()->getElementType();
1508 
1509  // Handle conversions to bool first, they are special: comparisons against 0.
1510  if (DstTy->isBooleanType()) {
1511  // Complex != 0 -> (Real != 0) | (Imag != 0)
1512  Src.first = EmitScalarConversion(Src.first, SrcTy, DstTy, Loc);
1513  Src.second = EmitScalarConversion(Src.second, SrcTy, DstTy, Loc);
1514  return Builder.CreateOr(Src.first, Src.second, "tobool");
1515  }
1516 
1517  // C99 6.3.1.7p2: "When a value of complex type is converted to a real type,
1518  // the imaginary part of the complex value is discarded and the value of the
1519  // real part is converted according to the conversion rules for the
1520  // corresponding real type.
1521  return EmitScalarConversion(Src.first, SrcTy, DstTy, Loc);
1522 }
1523 
1524 Value *ScalarExprEmitter::EmitNullValue(QualType Ty) {
1525  return CGF.EmitFromMemory(CGF.CGM.EmitNullConstant(Ty), Ty);
1526 }
1527 
1528 /// Emit a sanitization check for the given "binary" operation (which
1529 /// might actually be a unary increment which has been lowered to a binary
1530 /// operation). The check passes if all values in \p Checks (which are \c i1),
1531 /// are \c true.
1532 void ScalarExprEmitter::EmitBinOpCheck(
1533  ArrayRef<std::pair<Value *, SanitizerMask>> Checks, const BinOpInfo &Info) {
1534  assert(CGF.IsSanitizerScope);
1535  SanitizerHandler Check;
1537  SmallVector<llvm::Value *, 2> DynamicData;
1538 
1539  BinaryOperatorKind Opcode = Info.Opcode;
1542 
1543  StaticData.push_back(CGF.EmitCheckSourceLocation(Info.E->getExprLoc()));
1544  const UnaryOperator *UO = dyn_cast<UnaryOperator>(Info.E);
1545  if (UO && UO->getOpcode() == UO_Minus) {
1546  Check = SanitizerHandler::NegateOverflow;
1547  StaticData.push_back(CGF.EmitCheckTypeDescriptor(UO->getType()));
1548  DynamicData.push_back(Info.RHS);
1549  } else {
1550  if (BinaryOperator::isShiftOp(Opcode)) {
1551  // Shift LHS negative or too large, or RHS out of bounds.
1552  Check = SanitizerHandler::ShiftOutOfBounds;
1553  const BinaryOperator *BO = cast<BinaryOperator>(Info.E);
1554  StaticData.push_back(
1555  CGF.EmitCheckTypeDescriptor(BO->getLHS()->getType()));
1556  StaticData.push_back(
1557  CGF.EmitCheckTypeDescriptor(BO->getRHS()->getType()));
1558  } else if (Opcode == BO_Div || Opcode == BO_Rem) {
1559  // Divide or modulo by zero, or signed overflow (eg INT_MAX / -1).
1560  Check = SanitizerHandler::DivremOverflow;
1561  StaticData.push_back(CGF.EmitCheckTypeDescriptor(Info.Ty));
1562  } else {
1563  // Arithmetic overflow (+, -, *).
1564  switch (Opcode) {
1565  case BO_Add: Check = SanitizerHandler::AddOverflow; break;
1566  case BO_Sub: Check = SanitizerHandler::SubOverflow; break;
1567  case BO_Mul: Check = SanitizerHandler::MulOverflow; break;
1568  default: llvm_unreachable("unexpected opcode for bin op check");
1569  }
1570  StaticData.push_back(CGF.EmitCheckTypeDescriptor(Info.Ty));
1571  }
1572  DynamicData.push_back(Info.LHS);
1573  DynamicData.push_back(Info.RHS);
1574  }
1575 
1576  CGF.EmitCheck(Checks, Check, StaticData, DynamicData);
1577 }
1578 
1579 //===----------------------------------------------------------------------===//
1580 // Visitor Methods
1581 //===----------------------------------------------------------------------===//
1582 
1583 Value *ScalarExprEmitter::VisitExpr(Expr *E) {
1584  CGF.ErrorUnsupported(E, "scalar expression");
1585  if (E->getType()->isVoidType())
1586  return nullptr;
1587  return llvm::UndefValue::get(CGF.ConvertType(E->getType()));
1588 }
1589 
1590 Value *ScalarExprEmitter::VisitShuffleVectorExpr(ShuffleVectorExpr *E) {
1591  // Vector Mask Case
1592  if (E->getNumSubExprs() == 2) {
1593  Value *LHS = CGF.EmitScalarExpr(E->getExpr(0));
1594  Value *RHS = CGF.EmitScalarExpr(E->getExpr(1));
1595  Value *Mask;
1596 
1597  llvm::VectorType *LTy = cast<llvm::VectorType>(LHS->getType());
1598  unsigned LHSElts = LTy->getNumElements();
1599 
1600  Mask = RHS;
1601 
1602  llvm::VectorType *MTy = cast<llvm::VectorType>(Mask->getType());
1603 
1604  // Mask off the high bits of each shuffle index.
1605  Value *MaskBits =
1606  llvm::ConstantInt::get(MTy, llvm::NextPowerOf2(LHSElts - 1) - 1);
1607  Mask = Builder.CreateAnd(Mask, MaskBits, "mask");
1608 
1609  // newv = undef
1610  // mask = mask & maskbits
1611  // for each elt
1612  // n = extract mask i
1613  // x = extract val n
1614  // newv = insert newv, x, i
1615  llvm::VectorType *RTy = llvm::VectorType::get(LTy->getElementType(),
1616  MTy->getNumElements());
1617  Value* NewV = llvm::UndefValue::get(RTy);
1618  for (unsigned i = 0, e = MTy->getNumElements(); i != e; ++i) {
1619  Value *IIndx = llvm::ConstantInt::get(CGF.SizeTy, i);
1620  Value *Indx = Builder.CreateExtractElement(Mask, IIndx, "shuf_idx");
1621 
1622  Value *VExt = Builder.CreateExtractElement(LHS, Indx, "shuf_elt");
1623  NewV = Builder.CreateInsertElement(NewV, VExt, IIndx, "shuf_ins");
1624  }
1625  return NewV;
1626  }
1627 
1628  Value* V1 = CGF.EmitScalarExpr(E->getExpr(0));
1629  Value* V2 = CGF.EmitScalarExpr(E->getExpr(1));
1630 
1632  for (unsigned i = 2; i < E->getNumSubExprs(); ++i) {
1633  llvm::APSInt Idx = E->getShuffleMaskIdx(CGF.getContext(), i-2);
1634  // Check for -1 and output it as undef in the IR.
1635  if (Idx.isSigned() && Idx.isAllOnesValue())
1636  indices.push_back(llvm::UndefValue::get(CGF.Int32Ty));
1637  else
1638  indices.push_back(Builder.getInt32(Idx.getZExtValue()));
1639  }
1640 
1641  Value *SV = llvm::ConstantVector::get(indices);
1642  return Builder.CreateShuffleVector(V1, V2, SV, "shuffle");
1643 }
1644 
1645 Value *ScalarExprEmitter::VisitConvertVectorExpr(ConvertVectorExpr *E) {
1646  QualType SrcType = E->getSrcExpr()->getType(),
1647  DstType = E->getType();
1648 
1649  Value *Src = CGF.EmitScalarExpr(E->getSrcExpr());
1650 
1651  SrcType = CGF.getContext().getCanonicalType(SrcType);
1652  DstType = CGF.getContext().getCanonicalType(DstType);
1653  if (SrcType == DstType) return Src;
1654 
1655  assert(SrcType->isVectorType() &&
1656  "ConvertVector source type must be a vector");
1657  assert(DstType->isVectorType() &&
1658  "ConvertVector destination type must be a vector");
1659 
1660  llvm::Type *SrcTy = Src->getType();
1661  llvm::Type *DstTy = ConvertType(DstType);
1662 
1663  // Ignore conversions like int -> uint.
1664  if (SrcTy == DstTy)
1665  return Src;
1666 
1667  QualType SrcEltType = SrcType->castAs<VectorType>()->getElementType(),
1668  DstEltType = DstType->castAs<VectorType>()->getElementType();
1669 
1670  assert(SrcTy->isVectorTy() &&
1671  "ConvertVector source IR type must be a vector");
1672  assert(DstTy->isVectorTy() &&
1673  "ConvertVector destination IR type must be a vector");
1674 
1675  llvm::Type *SrcEltTy = SrcTy->getVectorElementType(),
1676  *DstEltTy = DstTy->getVectorElementType();
1677 
1678  if (DstEltType->isBooleanType()) {
1679  assert((SrcEltTy->isFloatingPointTy() ||
1680  isa<llvm::IntegerType>(SrcEltTy)) && "Unknown boolean conversion");
1681 
1682  llvm::Value *Zero = llvm::Constant::getNullValue(SrcTy);
1683  if (SrcEltTy->isFloatingPointTy()) {
1684  return Builder.CreateFCmpUNE(Src, Zero, "tobool");
1685  } else {
1686  return Builder.CreateICmpNE(Src, Zero, "tobool");
1687  }
1688  }
1689 
1690  // We have the arithmetic types: real int/float.
1691  Value *Res = nullptr;
1692 
1693  if (isa<llvm::IntegerType>(SrcEltTy)) {
1694  bool InputSigned = SrcEltType->isSignedIntegerOrEnumerationType();
1695  if (isa<llvm::IntegerType>(DstEltTy))
1696  Res = Builder.CreateIntCast(Src, DstTy, InputSigned, "conv");
1697  else if (InputSigned)
1698  Res = Builder.CreateSIToFP(Src, DstTy, "conv");
1699  else
1700  Res = Builder.CreateUIToFP(Src, DstTy, "conv");
1701  } else if (isa<llvm::IntegerType>(DstEltTy)) {
1702  assert(SrcEltTy->isFloatingPointTy() && "Unknown real conversion");
1703  if (DstEltType->isSignedIntegerOrEnumerationType())
1704  Res = Builder.CreateFPToSI(Src, DstTy, "conv");
1705  else
1706  Res = Builder.CreateFPToUI(Src, DstTy, "conv");
1707  } else {
1708  assert(SrcEltTy->isFloatingPointTy() && DstEltTy->isFloatingPointTy() &&
1709  "Unknown real conversion");
1710  if (DstEltTy->getTypeID() < SrcEltTy->getTypeID())
1711  Res = Builder.CreateFPTrunc(Src, DstTy, "conv");
1712  else
1713  Res = Builder.CreateFPExt(Src, DstTy, "conv");
1714  }
1715 
1716  return Res;
1717 }
1718 
1719 Value *ScalarExprEmitter::VisitMemberExpr(MemberExpr *E) {
1720  if (CodeGenFunction::ConstantEmission Constant = CGF.tryEmitAsConstant(E)) {
1721  CGF.EmitIgnoredExpr(E->getBase());
1722  return CGF.emitScalarConstant(Constant, E);
1723  } else {
1724  Expr::EvalResult Result;
1725  if (E->EvaluateAsInt(Result, CGF.getContext(), Expr::SE_AllowSideEffects)) {
1726  llvm::APSInt Value = Result.Val.getInt();
1727  CGF.EmitIgnoredExpr(E->getBase());
1728  return Builder.getInt(Value);
1729  }
1730  }
1731 
1732  return EmitLoadOfLValue(E);
1733 }
1734 
1735 Value *ScalarExprEmitter::VisitArraySubscriptExpr(ArraySubscriptExpr *E) {
1736  TestAndClearIgnoreResultAssign();
1737 
1738  // Emit subscript expressions in rvalue context's. For most cases, this just
1739  // loads the lvalue formed by the subscript expr. However, we have to be
1740  // careful, because the base of a vector subscript is occasionally an rvalue,
1741  // so we can't get it as an lvalue.
1742  if (!E->getBase()->getType()->isVectorType())
1743  return EmitLoadOfLValue(E);
1744 
1745  // Handle the vector case. The base must be a vector, the index must be an
1746  // integer value.
1747  Value *Base = Visit(E->getBase());
1748  Value *Idx = Visit(E->getIdx());
1749  QualType IdxTy = E->getIdx()->getType();
1750 
1751  if (CGF.SanOpts.has(SanitizerKind::ArrayBounds))
1752  CGF.EmitBoundsCheck(E, E->getBase(), Idx, IdxTy, /*Accessed*/true);
1753 
1754  return Builder.CreateExtractElement(Base, Idx, "vecext");
1755 }
1756 
1757 static llvm::Constant *getMaskElt(llvm::ShuffleVectorInst *SVI, unsigned Idx,
1758  unsigned Off, llvm::Type *I32Ty) {
1759  int MV = SVI->getMaskValue(Idx);
1760  if (MV == -1)
1761  return llvm::UndefValue::get(I32Ty);
1762  return llvm::ConstantInt::get(I32Ty, Off+MV);
1763 }
1764 
1765 static llvm::Constant *getAsInt32(llvm::ConstantInt *C, llvm::Type *I32Ty) {
1766  if (C->getBitWidth() != 32) {
1767  assert(llvm::ConstantInt::isValueValidForType(I32Ty,
1768  C->getZExtValue()) &&
1769  "Index operand too large for shufflevector mask!");
1770  return llvm::ConstantInt::get(I32Ty, C->getZExtValue());
1771  }
1772  return C;
1773 }
1774 
1775 Value *ScalarExprEmitter::VisitInitListExpr(InitListExpr *E) {
1776  bool Ignore = TestAndClearIgnoreResultAssign();
1777  (void)Ignore;
1778  assert (Ignore == false && "init list ignored");
1779  unsigned NumInitElements = E->getNumInits();
1780 
1781  if (E->hadArrayRangeDesignator())
1782  CGF.ErrorUnsupported(E, "GNU array range designator extension");
1783 
1784  llvm::VectorType *VType =
1785  dyn_cast<llvm::VectorType>(ConvertType(E->getType()));
1786 
1787  if (!VType) {
1788  if (NumInitElements == 0) {
1789  // C++11 value-initialization for the scalar.
1790  return EmitNullValue(E->getType());
1791  }
1792  // We have a scalar in braces. Just use the first element.
1793  return Visit(E->getInit(0));
1794  }
1795 
1796  unsigned ResElts = VType->getNumElements();
1797 
1798  // Loop over initializers collecting the Value for each, and remembering
1799  // whether the source was swizzle (ExtVectorElementExpr). This will allow
1800  // us to fold the shuffle for the swizzle into the shuffle for the vector
1801  // initializer, since LLVM optimizers generally do not want to touch
1802  // shuffles.
1803  unsigned CurIdx = 0;
1804  bool VIsUndefShuffle = false;
1805  llvm::Value *V = llvm::UndefValue::get(VType);
1806  for (unsigned i = 0; i != NumInitElements; ++i) {
1807  Expr *IE = E->getInit(i);
1808  Value *Init = Visit(IE);
1810 
1811  llvm::VectorType *VVT = dyn_cast<llvm::VectorType>(Init->getType());
1812 
1813  // Handle scalar elements. If the scalar initializer is actually one
1814  // element of a different vector of the same width, use shuffle instead of
1815  // extract+insert.
1816  if (!VVT) {
1817  if (isa<ExtVectorElementExpr>(IE)) {
1818  llvm::ExtractElementInst *EI = cast<llvm::ExtractElementInst>(Init);
1819 
1820  if (EI->getVectorOperandType()->getNumElements() == ResElts) {
1821  llvm::ConstantInt *C = cast<llvm::ConstantInt>(EI->getIndexOperand());
1822  Value *LHS = nullptr, *RHS = nullptr;
1823  if (CurIdx == 0) {
1824  // insert into undef -> shuffle (src, undef)
1825  // shufflemask must use an i32
1826  Args.push_back(getAsInt32(C, CGF.Int32Ty));
1827  Args.resize(ResElts, llvm::UndefValue::get(CGF.Int32Ty));
1828 
1829  LHS = EI->getVectorOperand();
1830  RHS = V;
1831  VIsUndefShuffle = true;
1832  } else if (VIsUndefShuffle) {
1833  // insert into undefshuffle && size match -> shuffle (v, src)
1834  llvm::ShuffleVectorInst *SVV = cast<llvm::ShuffleVectorInst>(V);
1835  for (unsigned j = 0; j != CurIdx; ++j)
1836  Args.push_back(getMaskElt(SVV, j, 0, CGF.Int32Ty));
1837  Args.push_back(Builder.getInt32(ResElts + C->getZExtValue()));
1838  Args.resize(ResElts, llvm::UndefValue::get(CGF.Int32Ty));
1839 
1840  LHS = cast<llvm::ShuffleVectorInst>(V)->getOperand(0);
1841  RHS = EI->getVectorOperand();
1842  VIsUndefShuffle = false;
1843  }
1844  if (!Args.empty()) {
1845  llvm::Constant *Mask = llvm::ConstantVector::get(Args);
1846  V = Builder.CreateShuffleVector(LHS, RHS, Mask);
1847  ++CurIdx;
1848  continue;
1849  }
1850  }
1851  }
1852  V = Builder.CreateInsertElement(V, Init, Builder.getInt32(CurIdx),
1853  "vecinit");
1854  VIsUndefShuffle = false;
1855  ++CurIdx;
1856  continue;
1857  }
1858 
1859  unsigned InitElts = VVT->getNumElements();
1860 
1861  // If the initializer is an ExtVecEltExpr (a swizzle), and the swizzle's
1862  // input is the same width as the vector being constructed, generate an
1863  // optimized shuffle of the swizzle input into the result.
1864  unsigned Offset = (CurIdx == 0) ? 0 : ResElts;
1865  if (isa<ExtVectorElementExpr>(IE)) {
1866  llvm::ShuffleVectorInst *SVI = cast<llvm::ShuffleVectorInst>(Init);
1867  Value *SVOp = SVI->getOperand(0);
1868  llvm::VectorType *OpTy = cast<llvm::VectorType>(SVOp->getType());
1869 
1870  if (OpTy->getNumElements() == ResElts) {
1871  for (unsigned j = 0; j != CurIdx; ++j) {
1872  // If the current vector initializer is a shuffle with undef, merge
1873  // this shuffle directly into it.
1874  if (VIsUndefShuffle) {
1875  Args.push_back(getMaskElt(cast<llvm::ShuffleVectorInst>(V), j, 0,
1876  CGF.Int32Ty));
1877  } else {
1878  Args.push_back(Builder.getInt32(j));
1879  }
1880  }
1881  for (unsigned j = 0, je = InitElts; j != je; ++j)
1882  Args.push_back(getMaskElt(SVI, j, Offset, CGF.Int32Ty));
1883  Args.resize(ResElts, llvm::UndefValue::get(CGF.Int32Ty));
1884 
1885  if (VIsUndefShuffle)
1886  V = cast<llvm::ShuffleVectorInst>(V)->getOperand(0);
1887 
1888  Init = SVOp;
1889  }
1890  }
1891 
1892  // Extend init to result vector length, and then shuffle its contribution
1893  // to the vector initializer into V.
1894  if (Args.empty()) {
1895  for (unsigned j = 0; j != InitElts; ++j)
1896  Args.push_back(Builder.getInt32(j));
1897  Args.resize(ResElts, llvm::UndefValue::get(CGF.Int32Ty));
1898  llvm::Constant *Mask = llvm::ConstantVector::get(Args);
1899  Init = Builder.CreateShuffleVector(Init, llvm::UndefValue::get(VVT),
1900  Mask, "vext");
1901 
1902  Args.clear();
1903  for (unsigned j = 0; j != CurIdx; ++j)
1904  Args.push_back(Builder.getInt32(j));
1905  for (unsigned j = 0; j != InitElts; ++j)
1906  Args.push_back(Builder.getInt32(j+Offset));
1907  Args.resize(ResElts, llvm::UndefValue::get(CGF.Int32Ty));
1908  }
1909 
1910  // If V is undef, make sure it ends up on the RHS of the shuffle to aid
1911  // merging subsequent shuffles into this one.
1912  if (CurIdx == 0)
1913  std::swap(V, Init);
1914  llvm::Constant *Mask = llvm::ConstantVector::get(Args);
1915  V = Builder.CreateShuffleVector(V, Init, Mask, "vecinit");
1916  VIsUndefShuffle = isa<llvm::UndefValue>(Init);
1917  CurIdx += InitElts;
1918  }
1919 
1920  // FIXME: evaluate codegen vs. shuffling against constant null vector.
1921  // Emit remaining default initializers.
1922  llvm::Type *EltTy = VType->getElementType();
1923 
1924  // Emit remaining default initializers
1925  for (/* Do not initialize i*/; CurIdx < ResElts; ++CurIdx) {
1926  Value *Idx = Builder.getInt32(CurIdx);
1927  llvm::Value *Init = llvm::Constant::getNullValue(EltTy);
1928  V = Builder.CreateInsertElement(V, Init, Idx, "vecinit");
1929  }
1930  return V;
1931 }
1932 
1934  const Expr *E = CE->getSubExpr();
1935 
1936  if (CE->getCastKind() == CK_UncheckedDerivedToBase)
1937  return false;
1938 
1939  if (isa<CXXThisExpr>(E->IgnoreParens())) {
1940  // We always assume that 'this' is never null.
1941  return false;
1942  }
1943 
1944  if (const ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(CE)) {
1945  // And that glvalue casts are never null.
1946  if (ICE->getValueKind() != VK_RValue)
1947  return false;
1948  }
1949 
1950  return true;
1951 }
1952 
1953 // VisitCastExpr - Emit code for an explicit or implicit cast. Implicit casts
1954 // have to handle a more broad range of conversions than explicit casts, as they
1955 // handle things like function to ptr-to-function decay etc.
1956 Value *ScalarExprEmitter::VisitCastExpr(CastExpr *CE) {
1957  Expr *E = CE->getSubExpr();
1958  QualType DestTy = CE->getType();
1959  CastKind Kind = CE->getCastKind();
1960 
1961  // These cases are generally not written to ignore the result of
1962  // evaluating their sub-expressions, so we clear this now.
1963  bool Ignored = TestAndClearIgnoreResultAssign();
1964 
1965  // Since almost all cast kinds apply to scalars, this switch doesn't have
1966  // a default case, so the compiler will warn on a missing case. The cases
1967  // are in the same order as in the CastKind enum.
1968  switch (Kind) {
1969  case CK_Dependent: llvm_unreachable("dependent cast kind in IR gen!");
1970  case CK_BuiltinFnToFnPtr:
1971  llvm_unreachable("builtin functions are handled elsewhere");
1972 
1973  case CK_LValueBitCast:
1974  case CK_ObjCObjectLValueCast: {
1975  Address Addr = EmitLValue(E).getAddress();
1976  Addr = Builder.CreateElementBitCast(Addr, CGF.ConvertTypeForMem(DestTy));
1977  LValue LV = CGF.MakeAddrLValue(Addr, DestTy);
1978  return EmitLoadOfLValue(LV, CE->getExprLoc());
1979  }
1980 
1981  case CK_LValueToRValueBitCast: {
1982  LValue SourceLVal = CGF.EmitLValue(E);
1983  Address Addr = Builder.CreateElementBitCast(SourceLVal.getAddress(),
1984  CGF.ConvertTypeForMem(DestTy));
1985  LValue DestLV = CGF.MakeAddrLValue(Addr, DestTy);
1987  return EmitLoadOfLValue(DestLV, CE->getExprLoc());
1988  }
1989 
1990  case CK_CPointerToObjCPointerCast:
1991  case CK_BlockPointerToObjCPointerCast:
1992  case CK_AnyPointerToBlockPointerCast:
1993  case CK_BitCast: {
1994  Value *Src = Visit(const_cast<Expr*>(E));
1995  llvm::Type *SrcTy = Src->getType();
1996  llvm::Type *DstTy = ConvertType(DestTy);
1997  if (SrcTy->isPtrOrPtrVectorTy() && DstTy->isPtrOrPtrVectorTy() &&
1998  SrcTy->getPointerAddressSpace() != DstTy->getPointerAddressSpace()) {
1999  llvm_unreachable("wrong cast for pointers in different address spaces"
2000  "(must be an address space cast)!");
2001  }
2002 
2003  if (CGF.SanOpts.has(SanitizerKind::CFIUnrelatedCast)) {
2004  if (auto PT = DestTy->getAs<PointerType>())
2005  CGF.EmitVTablePtrCheckForCast(PT->getPointeeType(), Src,
2006  /*MayBeNull=*/true,
2008  CE->getBeginLoc());
2009  }
2010 
2011  if (CGF.CGM.getCodeGenOpts().StrictVTablePointers) {
2012  const QualType SrcType = E->getType();
2013 
2014  if (SrcType.mayBeNotDynamicClass() && DestTy.mayBeDynamicClass()) {
2015  // Casting to pointer that could carry dynamic information (provided by
2016  // invariant.group) requires launder.
2017  Src = Builder.CreateLaunderInvariantGroup(Src);
2018  } else if (SrcType.mayBeDynamicClass() && DestTy.mayBeNotDynamicClass()) {
2019  // Casting to pointer that does not carry dynamic information (provided
2020  // by invariant.group) requires stripping it. Note that we don't do it
2021  // if the source could not be dynamic type and destination could be
2022  // dynamic because dynamic information is already laundered. It is
2023  // because launder(strip(src)) == launder(src), so there is no need to
2024  // add extra strip before launder.
2025  Src = Builder.CreateStripInvariantGroup(Src);
2026  }
2027  }
2028 
2029  // Update heapallocsite metadata when there is an explicit cast.
2030  if (llvm::CallInst *CI = dyn_cast<llvm::CallInst>(Src))
2031  if (CI->getMetadata("heapallocsite") && isa<ExplicitCastExpr>(CE))
2032  CGF.getDebugInfo()->
2033  addHeapAllocSiteMetadata(CI, CE->getType(), CE->getExprLoc());
2034 
2035  return Builder.CreateBitCast(Src, DstTy);
2036  }
2037  case CK_AddressSpaceConversion: {
2038  Expr::EvalResult Result;
2039  if (E->EvaluateAsRValue(Result, CGF.getContext()) &&
2040  Result.Val.isNullPointer()) {
2041  // If E has side effect, it is emitted even if its final result is a
2042  // null pointer. In that case, a DCE pass should be able to
2043  // eliminate the useless instructions emitted during translating E.
2044  if (Result.HasSideEffects)
2045  Visit(E);
2046  return CGF.CGM.getNullPointer(cast<llvm::PointerType>(
2047  ConvertType(DestTy)), DestTy);
2048  }
2049  // Since target may map different address spaces in AST to the same address
2050  // space, an address space conversion may end up as a bitcast.
2052  CGF, Visit(E), E->getType()->getPointeeType().getAddressSpace(),
2053  DestTy->getPointeeType().getAddressSpace(), ConvertType(DestTy));
2054  }
2055  case CK_AtomicToNonAtomic:
2056  case CK_NonAtomicToAtomic:
2057  case CK_NoOp:
2058  case CK_UserDefinedConversion:
2059  return Visit(const_cast<Expr*>(E));
2060 
2061  case CK_BaseToDerived: {
2062  const CXXRecordDecl *DerivedClassDecl = DestTy->getPointeeCXXRecordDecl();
2063  assert(DerivedClassDecl && "BaseToDerived arg isn't a C++ object pointer!");
2064 
2065  Address Base = CGF.EmitPointerWithAlignment(E);
2066  Address Derived =
2067  CGF.GetAddressOfDerivedClass(Base, DerivedClassDecl,
2068  CE->path_begin(), CE->path_end(),
2070 
2071  // C++11 [expr.static.cast]p11: Behavior is undefined if a downcast is
2072  // performed and the object is not of the derived type.
2073  if (CGF.sanitizePerformTypeCheck())
2075  Derived.getPointer(), DestTy->getPointeeType());
2076 
2077  if (CGF.SanOpts.has(SanitizerKind::CFIDerivedCast))
2079  DestTy->getPointeeType(), Derived.getPointer(),
2080  /*MayBeNull=*/true, CodeGenFunction::CFITCK_DerivedCast,
2081  CE->getBeginLoc());
2082 
2083  return Derived.getPointer();
2084  }
2085  case CK_UncheckedDerivedToBase:
2086  case CK_DerivedToBase: {
2087  // The EmitPointerWithAlignment path does this fine; just discard
2088  // the alignment.
2089  return CGF.EmitPointerWithAlignment(CE).getPointer();
2090  }
2091 
2092  case CK_Dynamic: {
2093  Address V = CGF.EmitPointerWithAlignment(E);
2094  const CXXDynamicCastExpr *DCE = cast<CXXDynamicCastExpr>(CE);
2095  return CGF.EmitDynamicCast(V, DCE);
2096  }
2097 
2098  case CK_ArrayToPointerDecay:
2099  return CGF.EmitArrayToPointerDecay(E).getPointer();
2100  case CK_FunctionToPointerDecay:
2101  return EmitLValue(E).getPointer();
2102 
2103  case CK_NullToPointer:
2104  if (MustVisitNullValue(E))
2105  CGF.EmitIgnoredExpr(E);
2106 
2107  return CGF.CGM.getNullPointer(cast<llvm::PointerType>(ConvertType(DestTy)),
2108  DestTy);
2109 
2110  case CK_NullToMemberPointer: {
2111  if (MustVisitNullValue(E))
2112  CGF.EmitIgnoredExpr(E);
2113 
2114  const MemberPointerType *MPT = CE->getType()->getAs<MemberPointerType>();
2115  return CGF.CGM.getCXXABI().EmitNullMemberPointer(MPT);
2116  }
2117 
2118  case CK_ReinterpretMemberPointer:
2119  case CK_BaseToDerivedMemberPointer:
2120  case CK_DerivedToBaseMemberPointer: {
2121  Value *Src = Visit(E);
2122 
2123  // Note that the AST doesn't distinguish between checked and
2124  // unchecked member pointer conversions, so we always have to
2125  // implement checked conversions here. This is inefficient when
2126  // actual control flow may be required in order to perform the
2127  // check, which it is for data member pointers (but not member
2128  // function pointers on Itanium and ARM).
2129  return CGF.CGM.getCXXABI().EmitMemberPointerConversion(CGF, CE, Src);
2130  }
2131 
2132  case CK_ARCProduceObject:
2133  return CGF.EmitARCRetainScalarExpr(E);
2134  case CK_ARCConsumeObject:
2135  return CGF.EmitObjCConsumeObject(E->getType(), Visit(E));
2136  case CK_ARCReclaimReturnedObject:
2137  return CGF.EmitARCReclaimReturnedObject(E, /*allowUnsafe*/ Ignored);
2138  case CK_ARCExtendBlockObject:
2139  return CGF.EmitARCExtendBlockObject(E);
2140 
2141  case CK_CopyAndAutoreleaseBlockObject:
2142  return CGF.EmitBlockCopyAndAutorelease(Visit(E), E->getType());
2143 
2144  case CK_FloatingRealToComplex:
2145  case CK_FloatingComplexCast:
2146  case CK_IntegralRealToComplex:
2147  case CK_IntegralComplexCast:
2148  case CK_IntegralComplexToFloatingComplex:
2149  case CK_FloatingComplexToIntegralComplex:
2150  case CK_ConstructorConversion:
2151  case CK_ToUnion:
2152  llvm_unreachable("scalar cast to non-scalar value");
2153 
2154  case CK_LValueToRValue:
2155  assert(CGF.getContext().hasSameUnqualifiedType(E->getType(), DestTy));
2156  assert(E->isGLValue() && "lvalue-to-rvalue applied to r-value!");
2157  return Visit(const_cast<Expr*>(E));
2158 
2159  case CK_IntegralToPointer: {
2160  Value *Src = Visit(const_cast<Expr*>(E));
2161 
2162  // First, convert to the correct width so that we control the kind of
2163  // extension.
2164  auto DestLLVMTy = ConvertType(DestTy);
2165  llvm::Type *MiddleTy = CGF.CGM.getDataLayout().getIntPtrType(DestLLVMTy);
2166  bool InputSigned = E->getType()->isSignedIntegerOrEnumerationType();
2167  llvm::Value* IntResult =
2168  Builder.CreateIntCast(Src, MiddleTy, InputSigned, "conv");
2169 
2170  auto *IntToPtr = Builder.CreateIntToPtr(IntResult, DestLLVMTy);
2171 
2172  if (CGF.CGM.getCodeGenOpts().StrictVTablePointers) {
2173  // Going from integer to pointer that could be dynamic requires reloading
2174  // dynamic information from invariant.group.
2175  if (DestTy.mayBeDynamicClass())
2176  IntToPtr = Builder.CreateLaunderInvariantGroup(IntToPtr);
2177  }
2178  return IntToPtr;
2179  }
2180  case CK_PointerToIntegral: {
2181  assert(!DestTy->isBooleanType() && "bool should use PointerToBool");
2182  auto *PtrExpr = Visit(E);
2183 
2184  if (CGF.CGM.getCodeGenOpts().StrictVTablePointers) {
2185  const QualType SrcType = E->getType();
2186 
2187  // Casting to integer requires stripping dynamic information as it does
2188  // not carries it.
2189  if (SrcType.mayBeDynamicClass())
2190  PtrExpr = Builder.CreateStripInvariantGroup(PtrExpr);
2191  }
2192 
2193  return Builder.CreatePtrToInt(PtrExpr, ConvertType(DestTy));
2194  }
2195  case CK_ToVoid: {
2196  CGF.EmitIgnoredExpr(E);
2197  return nullptr;
2198  }
2199  case CK_VectorSplat: {
2200  llvm::Type *DstTy = ConvertType(DestTy);
2201  Value *Elt = Visit(const_cast<Expr*>(E));
2202  // Splat the element across to all elements
2203  unsigned NumElements = DstTy->getVectorNumElements();
2204  return Builder.CreateVectorSplat(NumElements, Elt, "splat");
2205  }
2206 
2207  case CK_FixedPointCast:
2208  return EmitScalarConversion(Visit(E), E->getType(), DestTy,
2209  CE->getExprLoc());
2210 
2211  case CK_FixedPointToBoolean:
2212  assert(E->getType()->isFixedPointType() &&
2213  "Expected src type to be fixed point type");
2214  assert(DestTy->isBooleanType() && "Expected dest type to be boolean type");
2215  return EmitScalarConversion(Visit(E), E->getType(), DestTy,
2216  CE->getExprLoc());
2217 
2218  case CK_FixedPointToIntegral:
2219  assert(E->getType()->isFixedPointType() &&
2220  "Expected src type to be fixed point type");
2221  assert(DestTy->isIntegerType() && "Expected dest type to be an integer");
2222  return EmitScalarConversion(Visit(E), E->getType(), DestTy,
2223  CE->getExprLoc());
2224 
2225  case CK_IntegralToFixedPoint:
2226  assert(E->getType()->isIntegerType() &&
2227  "Expected src type to be an integer");
2228  assert(DestTy->isFixedPointType() &&
2229  "Expected dest type to be fixed point type");
2230  return EmitScalarConversion(Visit(E), E->getType(), DestTy,
2231  CE->getExprLoc());
2232 
2233  case CK_IntegralCast: {
2234  ScalarConversionOpts Opts;
2235  if (auto *ICE = dyn_cast<ImplicitCastExpr>(CE)) {
2236  if (!ICE->isPartOfExplicitCast())
2237  Opts = ScalarConversionOpts(CGF.SanOpts);
2238  }
2239  return EmitScalarConversion(Visit(E), E->getType(), DestTy,
2240  CE->getExprLoc(), Opts);
2241  }
2242  case CK_IntegralToFloating:
2243  case CK_FloatingToIntegral:
2244  case CK_FloatingCast:
2245  return EmitScalarConversion(Visit(E), E->getType(), DestTy,
2246  CE->getExprLoc());
2247  case CK_BooleanToSignedIntegral: {
2248  ScalarConversionOpts Opts;
2249  Opts.TreatBooleanAsSigned = true;
2250  return EmitScalarConversion(Visit(E), E->getType(), DestTy,
2251  CE->getExprLoc(), Opts);
2252  }
2253  case CK_IntegralToBoolean:
2254  return EmitIntToBoolConversion(Visit(E));
2255  case CK_PointerToBoolean:
2256  return EmitPointerToBoolConversion(Visit(E), E->getType());
2257  case CK_FloatingToBoolean:
2258  return EmitFloatToBoolConversion(Visit(E));
2259  case CK_MemberPointerToBoolean: {
2260  llvm::Value *MemPtr = Visit(E);
2261  const MemberPointerType *MPT = E->getType()->getAs<MemberPointerType>();
2262  return CGF.CGM.getCXXABI().EmitMemberPointerIsNotNull(CGF, MemPtr, MPT);
2263  }
2264 
2265  case CK_FloatingComplexToReal:
2266  case CK_IntegralComplexToReal:
2267  return CGF.EmitComplexExpr(E, false, true).first;
2268 
2269  case CK_FloatingComplexToBoolean:
2270  case CK_IntegralComplexToBoolean: {
2272 
2273  // TODO: kill this function off, inline appropriate case here
2274  return EmitComplexToScalarConversion(V, E->getType(), DestTy,
2275  CE->getExprLoc());
2276  }
2277 
2278  case CK_ZeroToOCLOpaqueType: {
2279  assert((DestTy->isEventT() || DestTy->isQueueT() ||
2280  DestTy->isOCLIntelSubgroupAVCType()) &&
2281  "CK_ZeroToOCLEvent cast on non-event type");
2282  return llvm::Constant::getNullValue(ConvertType(DestTy));
2283  }
2284 
2285  case CK_IntToOCLSampler:
2286  return CGF.CGM.createOpenCLIntToSamplerConversion(E, CGF);
2287 
2288  } // end of switch
2289 
2290  llvm_unreachable("unknown scalar cast");
2291 }
2292 
2293 Value *ScalarExprEmitter::VisitStmtExpr(const StmtExpr *E) {
2295  Address RetAlloca = CGF.EmitCompoundStmt(*E->getSubStmt(),
2296  !E->getType()->isVoidType());
2297  if (!RetAlloca.isValid())
2298  return nullptr;
2299  return CGF.EmitLoadOfScalar(CGF.MakeAddrLValue(RetAlloca, E->getType()),
2300  E->getExprLoc());
2301 }
2302 
2303 Value *ScalarExprEmitter::VisitExprWithCleanups(ExprWithCleanups *E) {
2304  CGF.enterFullExpression(E);
2306  Value *V = Visit(E->getSubExpr());
2307  // Defend against dominance problems caused by jumps out of expression
2308  // evaluation through the shared cleanup block.
2309  Scope.ForceCleanup({&V});
2310  return V;
2311 }
2312 
2313 //===----------------------------------------------------------------------===//
2314 // Unary Operators
2315 //===----------------------------------------------------------------------===//
2316 
2317 static BinOpInfo createBinOpInfoFromIncDec(const UnaryOperator *E,
2318  llvm::Value *InVal, bool IsInc) {
2319  BinOpInfo BinOp;
2320  BinOp.LHS = InVal;
2321  BinOp.RHS = llvm::ConstantInt::get(InVal->getType(), 1, false);
2322  BinOp.Ty = E->getType();
2323  BinOp.Opcode = IsInc ? BO_Add : BO_Sub;
2324  // FIXME: once UnaryOperator carries FPFeatures, copy it here.
2325  BinOp.E = E;
2326  return BinOp;
2327 }
2328 
2329 llvm::Value *ScalarExprEmitter::EmitIncDecConsiderOverflowBehavior(
2330  const UnaryOperator *E, llvm::Value *InVal, bool IsInc) {
2331  llvm::Value *Amount =
2332  llvm::ConstantInt::get(InVal->getType(), IsInc ? 1 : -1, true);
2333  StringRef Name = IsInc ? "inc" : "dec";
2334  switch (CGF.getLangOpts().getSignedOverflowBehavior()) {
2336  return Builder.CreateAdd(InVal, Amount, Name);
2338  if (!CGF.SanOpts.has(SanitizerKind::SignedIntegerOverflow))
2339  return Builder.CreateNSWAdd(InVal, Amount, Name);
2340  LLVM_FALLTHROUGH;
2342  if (!E->canOverflow())
2343  return Builder.CreateNSWAdd(InVal, Amount, Name);
2344  return EmitOverflowCheckedBinOp(createBinOpInfoFromIncDec(E, InVal, IsInc));
2345  }
2346  llvm_unreachable("Unknown SignedOverflowBehaviorTy");
2347 }
2348 
2349 llvm::Value *
2350 ScalarExprEmitter::EmitScalarPrePostIncDec(const UnaryOperator *E, LValue LV,
2351  bool isInc, bool isPre) {
2352 
2353  QualType type = E->getSubExpr()->getType();
2354  llvm::PHINode *atomicPHI = nullptr;
2355  llvm::Value *value;
2356  llvm::Value *input;
2357 
2358  int amount = (isInc ? 1 : -1);
2359  bool isSubtraction = !isInc;
2360 
2361  if (const AtomicType *atomicTy = type->getAs<AtomicType>()) {
2362  type = atomicTy->getValueType();
2363  if (isInc && type->isBooleanType()) {
2364  llvm::Value *True = CGF.EmitToMemory(Builder.getTrue(), type);
2365  if (isPre) {
2366  Builder.CreateStore(True, LV.getAddress(), LV.isVolatileQualified())
2367  ->setAtomic(llvm::AtomicOrdering::SequentiallyConsistent);
2368  return Builder.getTrue();
2369  }
2370  // For atomic bool increment, we just store true and return it for
2371  // preincrement, do an atomic swap with true for postincrement
2372  return Builder.CreateAtomicRMW(
2373  llvm::AtomicRMWInst::Xchg, LV.getPointer(), True,
2374  llvm::AtomicOrdering::SequentiallyConsistent);
2375  }
2376  // Special case for atomic increment / decrement on integers, emit
2377  // atomicrmw instructions. We skip this if we want to be doing overflow
2378  // checking, and fall into the slow path with the atomic cmpxchg loop.
2379  if (!type->isBooleanType() && type->isIntegerType() &&
2380  !(type->isUnsignedIntegerType() &&
2381  CGF.SanOpts.has(SanitizerKind::UnsignedIntegerOverflow)) &&
2382  CGF.getLangOpts().getSignedOverflowBehavior() !=
2384  llvm::AtomicRMWInst::BinOp aop = isInc ? llvm::AtomicRMWInst::Add :
2386  llvm::Instruction::BinaryOps op = isInc ? llvm::Instruction::Add :
2388  llvm::Value *amt = CGF.EmitToMemory(
2389  llvm::ConstantInt::get(ConvertType(type), 1, true), type);
2390  llvm::Value *old = Builder.CreateAtomicRMW(aop,
2391  LV.getPointer(), amt, llvm::AtomicOrdering::SequentiallyConsistent);
2392  return isPre ? Builder.CreateBinOp(op, old, amt) : old;
2393  }
2394  value = EmitLoadOfLValue(LV, E->getExprLoc());
2395  input = value;
2396  // For every other atomic operation, we need to emit a load-op-cmpxchg loop
2397  llvm::BasicBlock *startBB = Builder.GetInsertBlock();
2398  llvm::BasicBlock *opBB = CGF.createBasicBlock("atomic_op", CGF.CurFn);
2399  value = CGF.EmitToMemory(value, type);
2400  Builder.CreateBr(opBB);
2401  Builder.SetInsertPoint(opBB);
2402  atomicPHI = Builder.CreatePHI(value->getType(), 2);
2403  atomicPHI->addIncoming(value, startBB);
2404  value = atomicPHI;
2405  } else {
2406  value = EmitLoadOfLValue(LV, E->getExprLoc());
2407  input = value;
2408  }
2409 
2410  // Special case of integer increment that we have to check first: bool++.
2411  // Due to promotion rules, we get:
2412  // bool++ -> bool = bool + 1
2413  // -> bool = (int)bool + 1
2414  // -> bool = ((int)bool + 1 != 0)
2415  // An interesting aspect of this is that increment is always true.
2416  // Decrement does not have this property.
2417  if (isInc && type->isBooleanType()) {
2418  value = Builder.getTrue();
2419 
2420  // Most common case by far: integer increment.
2421  } else if (type->isIntegerType()) {
2422  // Note that signed integer inc/dec with width less than int can't
2423  // overflow because of promotion rules; we're just eliding a few steps here.
2424  if (E->canOverflow() && type->isSignedIntegerOrEnumerationType()) {
2425  value = EmitIncDecConsiderOverflowBehavior(E, value, isInc);
2426  } else if (E->canOverflow() && type->isUnsignedIntegerType() &&
2427  CGF.SanOpts.has(SanitizerKind::UnsignedIntegerOverflow)) {
2428  value =
2429  EmitOverflowCheckedBinOp(createBinOpInfoFromIncDec(E, value, isInc));
2430  } else {
2431  llvm::Value *amt = llvm::ConstantInt::get(value->getType(), amount, true);
2432  value = Builder.CreateAdd(value, amt, isInc ? "inc" : "dec");
2433  }
2434 
2435  // Next most common: pointer increment.
2436  } else if (const PointerType *ptr = type->getAs<PointerType>()) {
2437  QualType type = ptr->getPointeeType();
2438 
2439  // VLA types don't have constant size.
2440  if (const VariableArrayType *vla
2441  = CGF.getContext().getAsVariableArrayType(type)) {
2442  llvm::Value *numElts = CGF.getVLASize(vla).NumElts;
2443  if (!isInc) numElts = Builder.CreateNSWNeg(numElts, "vla.negsize");
2445  value = Builder.CreateGEP(value, numElts, "vla.inc");
2446  else
2447  value = CGF.EmitCheckedInBoundsGEP(
2448  value, numElts, /*SignedIndices=*/false, isSubtraction,
2449  E->getExprLoc(), "vla.inc");
2450 
2451  // Arithmetic on function pointers (!) is just +-1.
2452  } else if (type->isFunctionType()) {
2453  llvm::Value *amt = Builder.getInt32(amount);
2454 
2455  value = CGF.EmitCastToVoidPtr(value);
2457  value = Builder.CreateGEP(value, amt, "incdec.funcptr");
2458  else
2459  value = CGF.EmitCheckedInBoundsGEP(value, amt, /*SignedIndices=*/false,
2460  isSubtraction, E->getExprLoc(),
2461  "incdec.funcptr");
2462  value = Builder.CreateBitCast(value, input->getType());
2463 
2464  // For everything else, we can just do a simple increment.
2465  } else {
2466  llvm::Value *amt = Builder.getInt32(amount);
2468  value = Builder.CreateGEP(value, amt, "incdec.ptr");
2469  else
2470  value = CGF.EmitCheckedInBoundsGEP(value, amt, /*SignedIndices=*/false,
2471  isSubtraction, E->getExprLoc(),
2472  "incdec.ptr");
2473  }
2474 
2475  // Vector increment/decrement.
2476  } else if (type->isVectorType()) {
2477  if (type->hasIntegerRepresentation()) {
2478  llvm::Value *amt = llvm::ConstantInt::get(value->getType(), amount);
2479 
2480  value = Builder.CreateAdd(value, amt, isInc ? "inc" : "dec");
2481  } else {
2482  value = Builder.CreateFAdd(
2483  value,
2484  llvm::ConstantFP::get(value->getType(), amount),
2485  isInc ? "inc" : "dec");
2486  }
2487 
2488  // Floating point.
2489  } else if (type->isRealFloatingType()) {
2490  // Add the inc/dec to the real part.
2491  llvm::Value *amt;
2492 
2493  if (type->isHalfType() && !CGF.getContext().getLangOpts().NativeHalfType) {
2494  // Another special case: half FP increment should be done via float
2496  value = Builder.CreateCall(
2497  CGF.CGM.getIntrinsic(llvm::Intrinsic::convert_from_fp16,
2498  CGF.CGM.FloatTy),
2499  input, "incdec.conv");
2500  } else {
2501  value = Builder.CreateFPExt(input, CGF.CGM.FloatTy, "incdec.conv");
2502  }
2503  }
2504 
2505  if (value->getType()->isFloatTy())
2506  amt = llvm::ConstantFP::get(VMContext,
2507  llvm::APFloat(static_cast<float>(amount)));
2508  else if (value->getType()->isDoubleTy())
2509  amt = llvm::ConstantFP::get(VMContext,
2510  llvm::APFloat(static_cast<double>(amount)));
2511  else {
2512  // Remaining types are Half, LongDouble or __float128. Convert from float.
2513  llvm::APFloat F(static_cast<float>(amount));
2514  bool ignored;
2515  const llvm::fltSemantics *FS;
2516  // Don't use getFloatTypeSemantics because Half isn't
2517  // necessarily represented using the "half" LLVM type.
2518  if (value->getType()->isFP128Ty())
2519  FS = &CGF.getTarget().getFloat128Format();
2520  else if (value->getType()->isHalfTy())
2521  FS = &CGF.getTarget().getHalfFormat();
2522  else
2523  FS = &CGF.getTarget().getLongDoubleFormat();
2524  F.convert(*FS, llvm::APFloat::rmTowardZero, &ignored);
2525  amt = llvm::ConstantFP::get(VMContext, F);
2526  }
2527  value = Builder.CreateFAdd(value, amt, isInc ? "inc" : "dec");
2528 
2529  if (type->isHalfType() && !CGF.getContext().getLangOpts().NativeHalfType) {
2531  value = Builder.CreateCall(
2532  CGF.CGM.getIntrinsic(llvm::Intrinsic::convert_to_fp16,
2533  CGF.CGM.FloatTy),
2534  value, "incdec.conv");
2535  } else {
2536  value = Builder.CreateFPTrunc(value, input->getType(), "incdec.conv");
2537  }
2538  }
2539 
2540  // Objective-C pointer types.
2541  } else {
2542  const ObjCObjectPointerType *OPT = type->castAs<ObjCObjectPointerType>();
2543  value = CGF.EmitCastToVoidPtr(value);
2544 
2546  if (!isInc) size = -size;
2547  llvm::Value *sizeValue =
2548  llvm::ConstantInt::get(CGF.SizeTy, size.getQuantity());
2549 
2551  value = Builder.CreateGEP(value, sizeValue, "incdec.objptr");
2552  else
2553  value = CGF.EmitCheckedInBoundsGEP(value, sizeValue,
2554  /*SignedIndices=*/false, isSubtraction,
2555  E->getExprLoc(), "incdec.objptr");
2556  value = Builder.CreateBitCast(value, input->getType());
2557  }
2558 
2559  if (atomicPHI) {
2560  llvm::BasicBlock *curBlock = Builder.GetInsertBlock();
2561  llvm::BasicBlock *contBB = CGF.createBasicBlock("atomic_cont", CGF.CurFn);
2562  auto Pair = CGF.EmitAtomicCompareExchange(
2563  LV, RValue::get(atomicPHI), RValue::get(value), E->getExprLoc());
2564  llvm::Value *old = CGF.EmitToMemory(Pair.first.getScalarVal(), type);
2565  llvm::Value *success = Pair.second;
2566  atomicPHI->addIncoming(old, curBlock);
2567  Builder.CreateCondBr(success, contBB, atomicPHI->getParent());
2568  Builder.SetInsertPoint(contBB);
2569  return isPre ? value : input;
2570  }
2571 
2572  // Store the updated result through the lvalue.
2573  if (LV.isBitField())
2574  CGF.EmitStoreThroughBitfieldLValue(RValue::get(value), LV, &value);
2575  else
2576  CGF.EmitStoreThroughLValue(RValue::get(value), LV);
2577 
2578  // If this is a postinc, return the value read from memory, otherwise use the
2579  // updated value.
2580  return isPre ? value : input;
2581 }
2582 
2583 
2584 
2585 Value *ScalarExprEmitter::VisitUnaryMinus(const UnaryOperator *E) {
2586  TestAndClearIgnoreResultAssign();
2587  Value *Op = Visit(E->getSubExpr());
2588 
2589  // Generate a unary FNeg for FP ops.
2590  if (Op->getType()->isFPOrFPVectorTy())
2591  return Builder.CreateFNeg(Op, "fneg");
2592 
2593  // Emit unary minus with EmitSub so we handle overflow cases etc.
2594  BinOpInfo BinOp;
2595  BinOp.RHS = Op;
2596  BinOp.LHS = llvm::Constant::getNullValue(BinOp.RHS->getType());
2597  BinOp.Ty = E->getType();
2598  BinOp.Opcode = BO_Sub;
2599  // FIXME: once UnaryOperator carries FPFeatures, copy it here.
2600  BinOp.E = E;
2601  return EmitSub(BinOp);
2602 }
2603 
2604 Value *ScalarExprEmitter::VisitUnaryNot(const UnaryOperator *E) {
2605  TestAndClearIgnoreResultAssign();
2606  Value *Op = Visit(E->getSubExpr());
2607  return Builder.CreateNot(Op, "neg");
2608 }
2609 
2610 Value *ScalarExprEmitter::VisitUnaryLNot(const UnaryOperator *E) {
2611  // Perform vector logical not on comparison with zero vector.
2612  if (E->getType()->isExtVectorType()) {
2613  Value *Oper = Visit(E->getSubExpr());
2614  Value *Zero = llvm::Constant::getNullValue(Oper->getType());
2615  Value *Result;
2616  if (Oper->getType()->isFPOrFPVectorTy())
2617  Result = Builder.CreateFCmp(llvm::CmpInst::FCMP_OEQ, Oper, Zero, "cmp");
2618  else
2619  Result = Builder.CreateICmp(llvm::CmpInst::ICMP_EQ, Oper, Zero, "cmp");
2620  return Builder.CreateSExt(Result, ConvertType(E->getType()), "sext");
2621  }
2622 
2623  // Compare operand to zero.
2624  Value *BoolVal = CGF.EvaluateExprAsBool(E->getSubExpr());
2625 
2626  // Invert value.
2627  // TODO: Could dynamically modify easy computations here. For example, if
2628  // the operand is an icmp ne, turn into icmp eq.
2629  BoolVal = Builder.CreateNot(BoolVal, "lnot");
2630 
2631  // ZExt result to the expr type.
2632  return Builder.CreateZExt(BoolVal, ConvertType(E->getType()), "lnot.ext");
2633 }
2634 
2635 Value *ScalarExprEmitter::VisitOffsetOfExpr(OffsetOfExpr *E) {
2636  // Try folding the offsetof to a constant.
2637  Expr::EvalResult EVResult;
2638  if (E->EvaluateAsInt(EVResult, CGF.getContext())) {
2639  llvm::APSInt Value = EVResult.Val.getInt();
2640  return Builder.getInt(Value);
2641  }
2642 
2643  // Loop over the components of the offsetof to compute the value.
2644  unsigned n = E->getNumComponents();
2645  llvm::Type* ResultType = ConvertType(E->getType());
2646  llvm::Value* Result = llvm::Constant::getNullValue(ResultType);
2647  QualType CurrentType = E->getTypeSourceInfo()->getType();
2648  for (unsigned i = 0; i != n; ++i) {
2649  OffsetOfNode ON = E->getComponent(i);
2650  llvm::Value *Offset = nullptr;
2651  switch (ON.getKind()) {
2652  case OffsetOfNode::Array: {
2653  // Compute the index
2654  Expr *IdxExpr = E->getIndexExpr(ON.getArrayExprIndex());
2655  llvm::Value* Idx = CGF.EmitScalarExpr(IdxExpr);
2656  bool IdxSigned = IdxExpr->getType()->isSignedIntegerOrEnumerationType();
2657  Idx = Builder.CreateIntCast(Idx, ResultType, IdxSigned, "conv");
2658 
2659  // Save the element type
2660  CurrentType =
2661  CGF.getContext().getAsArrayType(CurrentType)->getElementType();
2662 
2663  // Compute the element size
2664  llvm::Value* ElemSize = llvm::ConstantInt::get(ResultType,
2665  CGF.getContext().getTypeSizeInChars(CurrentType).getQuantity());
2666 
2667  // Multiply out to compute the result
2668  Offset = Builder.CreateMul(Idx, ElemSize);
2669  break;
2670  }
2671 
2672  case OffsetOfNode::Field: {
2673  FieldDecl *MemberDecl = ON.getField();
2674  RecordDecl *RD = CurrentType->castAs<RecordType>()->getDecl();
2675  const ASTRecordLayout &RL = CGF.getContext().getASTRecordLayout(RD);
2676 
2677  // Compute the index of the field in its parent.
2678  unsigned i = 0;
2679  // FIXME: It would be nice if we didn't have to loop here!
2680  for (RecordDecl::field_iterator Field = RD->field_begin(),
2681  FieldEnd = RD->field_end();
2682  Field != FieldEnd; ++Field, ++i) {
2683  if (*Field == MemberDecl)
2684  break;
2685  }
2686  assert(i < RL.getFieldCount() && "offsetof field in wrong type");
2687 
2688  // Compute the offset to the field
2689  int64_t OffsetInt = RL.getFieldOffset(i) /
2690  CGF.getContext().getCharWidth();
2691  Offset = llvm::ConstantInt::get(ResultType, OffsetInt);
2692 
2693  // Save the element type.
2694  CurrentType = MemberDecl->getType();
2695  break;
2696  }
2697 
2699  llvm_unreachable("dependent __builtin_offsetof");
2700 
2701  case OffsetOfNode::Base: {
2702  if (ON.getBase()->isVirtual()) {
2703  CGF.ErrorUnsupported(E, "virtual base in offsetof");
2704  continue;
2705  }
2706 
2707  RecordDecl *RD = CurrentType->castAs<RecordType>()->getDecl();
2708  const ASTRecordLayout &RL = CGF.getContext().getASTRecordLayout(RD);
2709 
2710  // Save the element type.
2711  CurrentType = ON.getBase()->getType();
2712 
2713  // Compute the offset to the base.
2714  const RecordType *BaseRT = CurrentType->getAs<RecordType>();
2715  CXXRecordDecl *BaseRD = cast<CXXRecordDecl>(BaseRT->getDecl());
2716  CharUnits OffsetInt = RL.getBaseClassOffset(BaseRD);
2717  Offset = llvm::ConstantInt::get(ResultType, OffsetInt.getQuantity());
2718  break;
2719  }
2720  }
2721  Result = Builder.CreateAdd(Result, Offset);
2722  }
2723  return Result;
2724 }
2725 
2726 /// VisitUnaryExprOrTypeTraitExpr - Return the size or alignment of the type of
2727 /// argument of the sizeof expression as an integer.
2728 Value *
2729 ScalarExprEmitter::VisitUnaryExprOrTypeTraitExpr(
2730  const UnaryExprOrTypeTraitExpr *E) {
2731  QualType TypeToSize = E->getTypeOfArgument();
2732  if (E->getKind() == UETT_SizeOf) {
2733  if (const VariableArrayType *VAT =
2734  CGF.getContext().getAsVariableArrayType(TypeToSize)) {
2735  if (E->isArgumentType()) {
2736  // sizeof(type) - make sure to emit the VLA size.
2737  CGF.EmitVariablyModifiedType(TypeToSize);
2738  } else {
2739  // C99 6.5.3.4p2: If the argument is an expression of type
2740  // VLA, it is evaluated.
2741  CGF.EmitIgnoredExpr(E->getArgumentExpr());
2742  }
2743 
2744  auto VlaSize = CGF.getVLASize(VAT);
2745  llvm::Value *size = VlaSize.NumElts;
2746 
2747  // Scale the number of non-VLA elements by the non-VLA element size.
2748  CharUnits eltSize = CGF.getContext().getTypeSizeInChars(VlaSize.Type);
2749  if (!eltSize.isOne())
2750  size = CGF.Builder.CreateNUWMul(CGF.CGM.getSize(eltSize), size);
2751 
2752  return size;
2753  }
2754  } else if (E->getKind() == UETT_OpenMPRequiredSimdAlign) {
2755  auto Alignment =
2756  CGF.getContext()
2759  .getQuantity();
2760  return llvm::ConstantInt::get(CGF.SizeTy, Alignment);
2761  }
2762 
2763  // If this isn't sizeof(vla), the result must be constant; use the constant
2764  // folding logic so we don't have to duplicate it here.
2765  return Builder.getInt(E->EvaluateKnownConstInt(CGF.getContext()));
2766 }
2767 
2768 Value *ScalarExprEmitter::VisitUnaryReal(const UnaryOperator *E) {
2769  Expr *Op = E->getSubExpr();
2770  if (Op->getType()->isAnyComplexType()) {
2771  // If it's an l-value, load through the appropriate subobject l-value.
2772  // Note that we have to ask E because Op might be an l-value that
2773  // this won't work for, e.g. an Obj-C property.
2774  if (E->isGLValue())
2775  return CGF.EmitLoadOfLValue(CGF.EmitLValue(E),
2776  E->getExprLoc()).getScalarVal();
2777 
2778  // Otherwise, calculate and project.
2779  return CGF.EmitComplexExpr(Op, false, true).first;
2780  }
2781 
2782  return Visit(Op);
2783 }
2784 
2785 Value *ScalarExprEmitter::VisitUnaryImag(const UnaryOperator *E) {
2786  Expr *Op = E->getSubExpr();
2787  if (Op->getType()->isAnyComplexType()) {
2788  // If it's an l-value, load through the appropriate subobject l-value.
2789  // Note that we have to ask E because Op might be an l-value that
2790  // this won't work for, e.g. an Obj-C property.
2791  if (Op->isGLValue())
2792  return CGF.EmitLoadOfLValue(CGF.EmitLValue(E),
2793  E->getExprLoc()).getScalarVal();
2794 
2795  // Otherwise, calculate and project.
2796  return CGF.EmitComplexExpr(Op, true, false).second;
2797  }
2798 
2799  // __imag on a scalar returns zero. Emit the subexpr to ensure side
2800  // effects are evaluated, but not the actual value.
2801  if (Op->isGLValue())
2802  CGF.EmitLValue(Op);
2803  else
2804  CGF.EmitScalarExpr(Op, true);
2805  return llvm::Constant::getNullValue(ConvertType(E->getType()));
2806 }
2807 
2808 //===----------------------------------------------------------------------===//
2809 // Binary Operators
2810 //===----------------------------------------------------------------------===//
2811 
2812 BinOpInfo ScalarExprEmitter::EmitBinOps(const BinaryOperator *E) {
2813  TestAndClearIgnoreResultAssign();
2814  BinOpInfo Result;
2815  Result.LHS = Visit(E->getLHS());
2816  Result.RHS = Visit(E->getRHS());
2817  Result.Ty = E->getType();
2818  Result.Opcode = E->getOpcode();
2819  Result.FPFeatures = E->getFPFeatures();
2820  Result.E = E;
2821  return Result;
2822 }
2823 
2824 LValue ScalarExprEmitter::EmitCompoundAssignLValue(
2825  const CompoundAssignOperator *E,
2826  Value *(ScalarExprEmitter::*Func)(const BinOpInfo &),
2827  Value *&Result) {
2828  QualType LHSTy = E->getLHS()->getType();
2829  BinOpInfo OpInfo;
2830 
2832  return CGF.EmitScalarCompoundAssignWithComplex(E, Result);
2833 
2834  // Emit the RHS first. __block variables need to have the rhs evaluated
2835  // first, plus this should improve codegen a little.
2836  OpInfo.RHS = Visit(E->getRHS());
2837  OpInfo.Ty = E->getComputationResultType();
2838  OpInfo.Opcode = E->getOpcode();
2839  OpInfo.FPFeatures = E->getFPFeatures();
2840  OpInfo.E = E;
2841  // Load/convert the LHS.
2842  LValue LHSLV = EmitCheckedLValue(E->getLHS(), CodeGenFunction::TCK_Store);
2843 
2844  llvm::PHINode *atomicPHI = nullptr;
2845  if (const AtomicType *atomicTy = LHSTy->getAs<AtomicType>()) {
2846  QualType type = atomicTy->getValueType();
2847  if (!type->isBooleanType() && type->isIntegerType() &&
2848  !(type->isUnsignedIntegerType() &&
2849  CGF.SanOpts.has(SanitizerKind::UnsignedIntegerOverflow)) &&
2850  CGF.getLangOpts().getSignedOverflowBehavior() !=
2852  llvm::AtomicRMWInst::BinOp aop = llvm::AtomicRMWInst::BAD_BINOP;
2853  switch (OpInfo.Opcode) {
2854  // We don't have atomicrmw operands for *, %, /, <<, >>
2855  case BO_MulAssign: case BO_DivAssign:
2856  case BO_RemAssign:
2857  case BO_ShlAssign:
2858  case BO_ShrAssign:
2859  break;
2860  case BO_AddAssign:
2862  break;
2863  case BO_SubAssign:
2865  break;
2866  case BO_AndAssign:
2868  break;
2869  case BO_XorAssign:
2870  aop = llvm::AtomicRMWInst::Xor;
2871  break;
2872  case BO_OrAssign:
2873  aop = llvm::AtomicRMWInst::Or;
2874  break;
2875  default:
2876  llvm_unreachable("Invalid compound assignment type");
2877  }
2878  if (aop != llvm::AtomicRMWInst::BAD_BINOP) {
2879  llvm::Value *amt = CGF.EmitToMemory(
2880  EmitScalarConversion(OpInfo.RHS, E->getRHS()->getType(), LHSTy,
2881  E->getExprLoc()),
2882  LHSTy);
2883  Builder.CreateAtomicRMW(aop, LHSLV.getPointer(), amt,
2884  llvm::AtomicOrdering::SequentiallyConsistent);
2885  return LHSLV;
2886  }
2887  }
2888  // FIXME: For floating point types, we should be saving and restoring the
2889  // floating point environment in the loop.
2890  llvm::BasicBlock *startBB = Builder.GetInsertBlock();
2891  llvm::BasicBlock *opBB = CGF.createBasicBlock("atomic_op", CGF.CurFn);
2892  OpInfo.LHS = EmitLoadOfLValue(LHSLV, E->getExprLoc());
2893  OpInfo.LHS = CGF.EmitToMemory(OpInfo.LHS, type);
2894  Builder.CreateBr(opBB);
2895  Builder.SetInsertPoint(opBB);
2896  atomicPHI = Builder.CreatePHI(OpInfo.LHS->getType(), 2);
2897  atomicPHI->addIncoming(OpInfo.LHS, startBB);
2898  OpInfo.LHS = atomicPHI;
2899  }
2900  else
2901  OpInfo.LHS = EmitLoadOfLValue(LHSLV, E->getExprLoc());
2902 
2903  SourceLocation Loc = E->getExprLoc();
2904  OpInfo.LHS =
2905  EmitScalarConversion(OpInfo.LHS, LHSTy, E->getComputationLHSType(), Loc);
2906 
2907  // Expand the binary operator.
2908  Result = (this->*Func)(OpInfo);
2909 
2910  // Convert the result back to the LHS type,
2911  // potentially with Implicit Conversion sanitizer check.
2912  Result = EmitScalarConversion(Result, E->getComputationResultType(), LHSTy,
2913  Loc, ScalarConversionOpts(CGF.SanOpts));
2914 
2915  if (atomicPHI) {
2916  llvm::BasicBlock *curBlock = Builder.GetInsertBlock();
2917  llvm::BasicBlock *contBB = CGF.createBasicBlock("atomic_cont", CGF.CurFn);
2918  auto Pair = CGF.EmitAtomicCompareExchange(
2919  LHSLV, RValue::get(atomicPHI), RValue::get(Result), E->getExprLoc());
2920  llvm::Value *old = CGF.EmitToMemory(Pair.first.getScalarVal(), LHSTy);
2921  llvm::Value *success = Pair.second;
2922  atomicPHI->addIncoming(old, curBlock);
2923  Builder.CreateCondBr(success, contBB, atomicPHI->getParent());
2924  Builder.SetInsertPoint(contBB);
2925  return LHSLV;
2926  }
2927 
2928  // Store the result value into the LHS lvalue. Bit-fields are handled
2929  // specially because the result is altered by the store, i.e., [C99 6.5.16p1]
2930  // 'An assignment expression has the value of the left operand after the
2931  // assignment...'.
2932  if (LHSLV.isBitField())
2933  CGF.EmitStoreThroughBitfieldLValue(RValue::get(Result), LHSLV, &Result);
2934  else
2935  CGF.EmitStoreThroughLValue(RValue::get(Result), LHSLV);
2936 
2937  return LHSLV;
2938 }
2939 
2940 Value *ScalarExprEmitter::EmitCompoundAssign(const CompoundAssignOperator *E,
2941  Value *(ScalarExprEmitter::*Func)(const BinOpInfo &)) {
2942  bool Ignore = TestAndClearIgnoreResultAssign();
2943  Value *RHS = nullptr;
2944  LValue LHS = EmitCompoundAssignLValue(E, Func, RHS);
2945 
2946  // If the result is clearly ignored, return now.
2947  if (Ignore)
2948  return nullptr;
2949 
2950  // The result of an assignment in C is the assigned r-value.
2951  if (!CGF.getLangOpts().CPlusPlus)
2952  return RHS;
2953 
2954  // If the lvalue is non-volatile, return the computed value of the assignment.
2955  if (!LHS.isVolatileQualified())
2956  return RHS;
2957 
2958  // Otherwise, reload the value.
2959  return EmitLoadOfLValue(LHS, E->getExprLoc());
2960 }
2961 
2962 void ScalarExprEmitter::EmitUndefinedBehaviorIntegerDivAndRemCheck(
2963  const BinOpInfo &Ops, llvm::Value *Zero, bool isDiv) {
2965 
2966  if (CGF.SanOpts.has(SanitizerKind::IntegerDivideByZero)) {
2967  Checks.push_back(std::make_pair(Builder.CreateICmpNE(Ops.RHS, Zero),
2968  SanitizerKind::IntegerDivideByZero));
2969  }
2970 
2971  const auto *BO = cast<BinaryOperator>(Ops.E);
2972  if (CGF.SanOpts.has(SanitizerKind::SignedIntegerOverflow) &&
2973  Ops.Ty->hasSignedIntegerRepresentation() &&
2974  !IsWidenedIntegerOp(CGF.getContext(), BO->getLHS()) &&
2975  Ops.mayHaveIntegerOverflow()) {
2976  llvm::IntegerType *Ty = cast<llvm::IntegerType>(Zero->getType());
2977 
2978  llvm::Value *IntMin =
2979  Builder.getInt(llvm::APInt::getSignedMinValue(Ty->getBitWidth()));
2980  llvm::Value *NegOne = llvm::ConstantInt::get(Ty, -1ULL);
2981 
2982  llvm::Value *LHSCmp = Builder.CreateICmpNE(Ops.LHS, IntMin);
2983  llvm::Value *RHSCmp = Builder.CreateICmpNE(Ops.RHS, NegOne);
2984  llvm::Value *NotOverflow = Builder.CreateOr(LHSCmp, RHSCmp, "or");
2985  Checks.push_back(
2986  std::make_pair(NotOverflow, SanitizerKind::SignedIntegerOverflow));
2987  }
2988 
2989  if (Checks.size() > 0)
2990  EmitBinOpCheck(Checks, Ops);
2991 }
2992 
2993 Value *ScalarExprEmitter::EmitDiv(const BinOpInfo &Ops) {
2994  {
2995  CodeGenFunction::SanitizerScope SanScope(&CGF);
2996  if ((CGF.SanOpts.has(SanitizerKind::IntegerDivideByZero) ||
2997  CGF.SanOpts.has(SanitizerKind::SignedIntegerOverflow)) &&
2998  Ops.Ty->isIntegerType() &&
2999  (Ops.mayHaveIntegerDivisionByZero() || Ops.mayHaveIntegerOverflow())) {
3000  llvm::Value *Zero = llvm::Constant::getNullValue(ConvertType(Ops.Ty));
3001  EmitUndefinedBehaviorIntegerDivAndRemCheck(Ops, Zero, true);
3002  } else if (CGF.SanOpts.has(SanitizerKind::FloatDivideByZero) &&
3003  Ops.Ty->isRealFloatingType() &&
3004  Ops.mayHaveFloatDivisionByZero()) {
3005  llvm::Value *Zero = llvm::Constant::getNullValue(ConvertType(Ops.Ty));
3006  llvm::Value *NonZero = Builder.CreateFCmpUNE(Ops.RHS, Zero);
3007  EmitBinOpCheck(std::make_pair(NonZero, SanitizerKind::FloatDivideByZero),
3008  Ops);
3009  }
3010  }
3011 
3012  if (Ops.LHS->getType()->isFPOrFPVectorTy()) {
3013  llvm::Value *Val = Builder.CreateFDiv(Ops.LHS, Ops.RHS, "div");
3014  if (CGF.getLangOpts().OpenCL &&
3015  !CGF.CGM.getCodeGenOpts().CorrectlyRoundedDivSqrt) {
3016  // OpenCL v1.1 s7.4: minimum accuracy of single precision / is 2.5ulp
3017  // OpenCL v1.2 s5.6.4.2: The -cl-fp32-correctly-rounded-divide-sqrt
3018  // build option allows an application to specify that single precision
3019  // floating-point divide (x/y and 1/x) and sqrt used in the program
3020  // source are correctly rounded.
3021  llvm::Type *ValTy = Val->getType();
3022  if (ValTy->isFloatTy() ||
3023  (isa<llvm::VectorType>(ValTy) &&
3024  cast<llvm::VectorType>(ValTy)->getElementType()->isFloatTy()))
3025  CGF.SetFPAccuracy(Val, 2.5);
3026  }
3027  return Val;
3028  }
3029  else if (Ops.Ty->hasUnsignedIntegerRepresentation())
3030  return Builder.CreateUDiv(Ops.LHS, Ops.RHS, "div");
3031  else
3032  return Builder.CreateSDiv(Ops.LHS, Ops.RHS, "div");
3033 }
3034 
3035 Value *ScalarExprEmitter::EmitRem(const BinOpInfo &Ops) {
3036  // Rem in C can't be a floating point type: C99 6.5.5p2.
3037  if ((CGF.SanOpts.has(SanitizerKind::IntegerDivideByZero) ||
3038  CGF.SanOpts.has(SanitizerKind::SignedIntegerOverflow)) &&
3039  Ops.Ty->isIntegerType() &&
3040  (Ops.mayHaveIntegerDivisionByZero() || Ops.mayHaveIntegerOverflow())) {
3041  CodeGenFunction::SanitizerScope SanScope(&CGF);
3042  llvm::Value *Zero = llvm::Constant::getNullValue(ConvertType(Ops.Ty));
3043  EmitUndefinedBehaviorIntegerDivAndRemCheck(Ops, Zero, false);
3044  }
3045 
3046  if (Ops.Ty->hasUnsignedIntegerRepresentation())
3047  return Builder.CreateURem(Ops.LHS, Ops.RHS, "rem");
3048  else
3049  return Builder.CreateSRem(Ops.LHS, Ops.RHS, "rem");
3050 }
3051 
3052 Value *ScalarExprEmitter::EmitOverflowCheckedBinOp(const BinOpInfo &Ops) {
3053  unsigned IID;
3054  unsigned OpID = 0;
3055 
3056  bool isSigned = Ops.Ty->isSignedIntegerOrEnumerationType();
3057  switch (Ops.Opcode) {
3058  case BO_Add:
3059  case BO_AddAssign:
3060  OpID = 1;
3061  IID = isSigned ? llvm::Intrinsic::sadd_with_overflow :
3062  llvm::Intrinsic::uadd_with_overflow;
3063  break;
3064  case BO_Sub:
3065  case BO_SubAssign:
3066  OpID = 2;
3067  IID = isSigned ? llvm::Intrinsic::ssub_with_overflow :
3068  llvm::Intrinsic::usub_with_overflow;
3069  break;
3070  case BO_Mul:
3071  case BO_MulAssign:
3072  OpID = 3;
3073  IID = isSigned ? llvm::Intrinsic::smul_with_overflow :
3074  llvm::Intrinsic::umul_with_overflow;
3075  break;
3076  default:
3077  llvm_unreachable("Unsupported operation for overflow detection");
3078  }
3079  OpID <<= 1;
3080  if (isSigned)
3081  OpID |= 1;
3082 
3083  CodeGenFunction::SanitizerScope SanScope(&CGF);
3084  llvm::Type *opTy = CGF.CGM.getTypes().ConvertType(Ops.Ty);
3085 
3086  llvm::Function *intrinsic = CGF.CGM.getIntrinsic(IID, opTy);
3087 
3088  Value *resultAndOverflow = Builder.CreateCall(intrinsic, {Ops.LHS, Ops.RHS});
3089  Value *result = Builder.CreateExtractValue(resultAndOverflow, 0);
3090  Value *overflow = Builder.CreateExtractValue(resultAndOverflow, 1);
3091 
3092  // Handle overflow with llvm.trap if no custom handler has been specified.
3093  const std::string *handlerName =
3095  if (handlerName->empty()) {
3096  // If the signed-integer-overflow sanitizer is enabled, emit a call to its
3097  // runtime. Otherwise, this is a -ftrapv check, so just emit a trap.
3098  if (!isSigned || CGF.SanOpts.has(SanitizerKind::SignedIntegerOverflow)) {
3099  llvm::Value *NotOverflow = Builder.CreateNot(overflow);
3100  SanitizerMask Kind = isSigned ? SanitizerKind::SignedIntegerOverflow
3101  : SanitizerKind::UnsignedIntegerOverflow;
3102  EmitBinOpCheck(std::make_pair(NotOverflow, Kind), Ops);
3103  } else
3104  CGF.EmitTrapCheck(Builder.CreateNot(overflow));
3105  return result;
3106  }
3107 
3108  // Branch in case of overflow.
3109  llvm::BasicBlock *initialBB = Builder.GetInsertBlock();
3110  llvm::BasicBlock *continueBB =
3111  CGF.createBasicBlock("nooverflow", CGF.CurFn, initialBB->getNextNode());
3112  llvm::BasicBlock *overflowBB = CGF.createBasicBlock("overflow", CGF.CurFn);
3113 
3114  Builder.CreateCondBr(overflow, overflowBB, continueBB);
3115 
3116  // If an overflow handler is set, then we want to call it and then use its
3117  // result, if it returns.
3118  Builder.SetInsertPoint(overflowBB);
3119 
3120  // Get the overflow handler.
3121  llvm::Type *Int8Ty = CGF.Int8Ty;
3122  llvm::Type *argTypes[] = { CGF.Int64Ty, CGF.Int64Ty, Int8Ty, Int8Ty };
3123  llvm::FunctionType *handlerTy =
3124  llvm::FunctionType::get(CGF.Int64Ty, argTypes, true);
3125  llvm::FunctionCallee handler =
3126  CGF.CGM.CreateRuntimeFunction(handlerTy, *handlerName);
3127 
3128  // Sign extend the args to 64-bit, so that we can use the same handler for
3129  // all types of overflow.
3130  llvm::Value *lhs = Builder.CreateSExt(Ops.LHS, CGF.Int64Ty);
3131  llvm::Value *rhs = Builder.CreateSExt(Ops.RHS, CGF.Int64Ty);
3132 
3133  // Call the handler with the two arguments, the operation, and the size of
3134  // the result.
3135  llvm::Value *handlerArgs[] = {
3136  lhs,
3137  rhs,
3138  Builder.getInt8(OpID),
3139  Builder.getInt8(cast<llvm::IntegerType>(opTy)->getBitWidth())
3140  };
3141  llvm::Value *handlerResult =
3142  CGF.EmitNounwindRuntimeCall(handler, handlerArgs);
3143 
3144  // Truncate the result back to the desired size.
3145  handlerResult = Builder.CreateTrunc(handlerResult, opTy);
3146  Builder.CreateBr(continueBB);
3147 
3148  Builder.SetInsertPoint(continueBB);
3149  llvm::PHINode *phi = Builder.CreatePHI(opTy, 2);
3150  phi->addIncoming(result, initialBB);
3151  phi->addIncoming(handlerResult, overflowBB);
3152 
3153  return phi;
3154 }
3155 
3156 /// Emit pointer + index arithmetic.
3158  const BinOpInfo &op,
3159  bool isSubtraction) {
3160  // Must have binary (not unary) expr here. Unary pointer
3161  // increment/decrement doesn't use this path.
3162  const BinaryOperator *expr = cast<BinaryOperator>(op.E);
3163 
3164  Value *pointer = op.LHS;
3165  Expr *pointerOperand = expr->getLHS();
3166  Value *index = op.RHS;
3167  Expr *indexOperand = expr->getRHS();
3168 
3169  // In a subtraction, the LHS is always the pointer.
3170  if (!isSubtraction && !pointer->getType()->isPointerTy()) {
3171  std::swap(pointer, index);
3172  std::swap(pointerOperand, indexOperand);
3173  }
3174 
3175  bool isSigned = indexOperand->getType()->isSignedIntegerOrEnumerationType();
3176 
3177  unsigned width = cast<llvm::IntegerType>(index->getType())->getBitWidth();
3178  auto &DL = CGF.CGM.getDataLayout();
3179  auto PtrTy = cast<llvm::PointerType>(pointer->getType());
3180 
3181  // Some versions of glibc and gcc use idioms (particularly in their malloc
3182  // routines) that add a pointer-sized integer (known to be a pointer value)
3183  // to a null pointer in order to cast the value back to an integer or as
3184  // part of a pointer alignment algorithm. This is undefined behavior, but
3185  // we'd like to be able to compile programs that use it.
3186  //
3187  // Normally, we'd generate a GEP with a null-pointer base here in response
3188  // to that code, but it's also UB to dereference a pointer created that
3189  // way. Instead (as an acknowledged hack to tolerate the idiom) we will
3190  // generate a direct cast of the integer value to a pointer.
3191  //
3192  // The idiom (p = nullptr + N) is not met if any of the following are true:
3193  //
3194  // The operation is subtraction.
3195  // The index is not pointer-sized.
3196  // The pointer type is not byte-sized.
3197  //
3199  op.Opcode,
3200  expr->getLHS(),
3201  expr->getRHS()))
3202  return CGF.Builder.CreateIntToPtr(index, pointer->getType());
3203 
3204  if (width != DL.getTypeSizeInBits(PtrTy)) {
3205  // Zero-extend or sign-extend the pointer value according to
3206  // whether the index is signed or not.
3207  index = CGF.Builder.CreateIntCast(index, DL.getIntPtrType(PtrTy), isSigned,
3208  "idx.ext");
3209  }
3210 
3211  // If this is subtraction, negate the index.
3212  if (isSubtraction)
3213  index = CGF.Builder.CreateNeg(index, "idx.neg");
3214 
3215  if (CGF.SanOpts.has(SanitizerKind::ArrayBounds))
3216  CGF.EmitBoundsCheck(op.E, pointerOperand, index, indexOperand->getType(),
3217  /*Accessed*/ false);
3218 
3219  const PointerType *pointerType
3220  = pointerOperand->getType()->getAs<PointerType>();
3221  if (!pointerType) {
3222  QualType objectType = pointerOperand->getType()
3224  ->getPointeeType();
3225  llvm::Value *objectSize
3226  = CGF.CGM.getSize(CGF.getContext().getTypeSizeInChars(objectType));
3227 
3228  index = CGF.Builder.CreateMul(index, objectSize);
3229 
3230  Value *result = CGF.Builder.CreateBitCast(pointer, CGF.VoidPtrTy);
3231  result = CGF.Builder.CreateGEP(result, index, "add.ptr");
3232  return CGF.Builder.CreateBitCast(result, pointer->getType());
3233  }
3234 
3235  QualType elementType = pointerType->getPointeeType();
3236  if (const VariableArrayType *vla
3237  = CGF.getContext().getAsVariableArrayType(elementType)) {
3238  // The element count here is the total number of non-VLA elements.
3239  llvm::Value *numElements = CGF.getVLASize(vla).NumElts;
3240 
3241  // Effectively, the multiply by the VLA size is part of the GEP.
3242  // GEP indexes are signed, and scaling an index isn't permitted to
3243  // signed-overflow, so we use the same semantics for our explicit
3244  // multiply. We suppress this if overflow is not undefined behavior.
3245  if (CGF.getLangOpts().isSignedOverflowDefined()) {
3246  index = CGF.Builder.CreateMul(index, numElements, "vla.index");
3247  pointer = CGF.Builder.CreateGEP(pointer, index, "add.ptr");
3248  } else {
3249  index = CGF.Builder.CreateNSWMul(index, numElements, "vla.index");
3250  pointer =
3251  CGF.EmitCheckedInBoundsGEP(pointer, index, isSigned, isSubtraction,
3252  op.E->getExprLoc(), "add.ptr");
3253  }
3254  return pointer;
3255  }
3256 
3257  // Explicitly handle GNU void* and function pointer arithmetic extensions. The
3258  // GNU void* casts amount to no-ops since our void* type is i8*, but this is
3259  // future proof.
3260  if (elementType->isVoidType() || elementType->isFunctionType()) {
3261  Value *result = CGF.Builder.CreateBitCast(pointer, CGF.VoidPtrTy);
3262  result = CGF.Builder.CreateGEP(result, index, "add.ptr");
3263  return CGF.Builder.CreateBitCast(result, pointer->getType());
3264  }
3265 
3267  return CGF.Builder.CreateGEP(pointer, index, "add.ptr");
3268 
3269  return CGF.EmitCheckedInBoundsGEP(pointer, index, isSigned, isSubtraction,
3270  op.E->getExprLoc(), "add.ptr");
3271 }
3272 
3273 // Construct an fmuladd intrinsic to represent a fused mul-add of MulOp and
3274 // Addend. Use negMul and negAdd to negate the first operand of the Mul or
3275 // the add operand respectively. This allows fmuladd to represent a*b-c, or
3276 // c-a*b. Patterns in LLVM should catch the negated forms and translate them to
3277 // efficient operations.
3278 static Value* buildFMulAdd(llvm::BinaryOperator *MulOp, Value *Addend,
3279  const CodeGenFunction &CGF, CGBuilderTy &Builder,
3280  bool negMul, bool negAdd) {
3281  assert(!(negMul && negAdd) && "Only one of negMul and negAdd should be set.");
3282 
3283  Value *MulOp0 = MulOp->getOperand(0);
3284  Value *MulOp1 = MulOp->getOperand(1);
3285  if (negMul) {
3286  MulOp0 =
3287  Builder.CreateFSub(
3288  llvm::ConstantFP::getZeroValueForNegation(MulOp0->getType()), MulOp0,
3289  "neg");
3290  } else if (negAdd) {
3291  Addend =
3292  Builder.CreateFSub(
3293  llvm::ConstantFP::getZeroValueForNegation(Addend->getType()), Addend,
3294  "neg");
3295  }
3296 
3297  Value *FMulAdd = Builder.CreateCall(
3298  CGF.CGM.getIntrinsic(llvm::Intrinsic::fmuladd, Addend->getType()),
3299  {MulOp0, MulOp1, Addend});
3300  MulOp->eraseFromParent();
3301 
3302  return FMulAdd;
3303 }
3304 
3305 // Check whether it would be legal to emit an fmuladd intrinsic call to
3306 // represent op and if so, build the fmuladd.
3307 //
3308 // Checks that (a) the operation is fusable, and (b) -ffp-contract=on.
3309 // Does NOT check the type of the operation - it's assumed that this function
3310 // will be called from contexts where it's known that the type is contractable.
3311 static Value* tryEmitFMulAdd(const BinOpInfo &op,
3312  const CodeGenFunction &CGF, CGBuilderTy &Builder,
3313  bool isSub=false) {
3314 
3315  assert((op.Opcode == BO_Add || op.Opcode == BO_AddAssign ||
3316  op.Opcode == BO_Sub || op.Opcode == BO_SubAssign) &&
3317  "Only fadd/fsub can be the root of an fmuladd.");
3318 
3319  // Check whether this op is marked as fusable.
3320  if (!op.FPFeatures.allowFPContractWithinStatement())
3321  return nullptr;
3322 
3323  // We have a potentially fusable op. Look for a mul on one of the operands.
3324  // Also, make sure that the mul result isn't used directly. In that case,
3325  // there's no point creating a muladd operation.
3326  if (auto *LHSBinOp = dyn_cast<llvm::BinaryOperator>(op.LHS)) {
3327  if (LHSBinOp->getOpcode() == llvm::Instruction::FMul &&
3328  LHSBinOp->use_empty())
3329  return buildFMulAdd(LHSBinOp, op.RHS, CGF, Builder, false, isSub);
3330  }
3331  if (auto *RHSBinOp = dyn_cast<llvm::BinaryOperator>(op.RHS)) {
3332  if (RHSBinOp->getOpcode() == llvm::Instruction::FMul &&
3333  RHSBinOp->use_empty())
3334  return buildFMulAdd(RHSBinOp, op.LHS, CGF, Builder, isSub, false);
3335  }
3336 
3337  return nullptr;
3338 }
3339 
3340 Value *ScalarExprEmitter::EmitAdd(const BinOpInfo &op) {
3341  if (op.LHS->getType()->isPointerTy() ||
3342  op.RHS->getType()->isPointerTy())
3344 
3345  if (op.Ty->isSignedIntegerOrEnumerationType()) {
3346  switch (CGF.getLangOpts().getSignedOverflowBehavior()) {
3348  return Builder.CreateAdd(op.LHS, op.RHS, "add");
3350  if (!CGF.SanOpts.has(SanitizerKind::SignedIntegerOverflow))
3351  return Builder.CreateNSWAdd(op.LHS, op.RHS, "add");
3352  LLVM_FALLTHROUGH;
3354  if (CanElideOverflowCheck(CGF.getContext(), op))
3355  return Builder.CreateNSWAdd(op.LHS, op.RHS, "add");
3356  return EmitOverflowCheckedBinOp(op);
3357  }
3358  }
3359 
3360  if (op.Ty->isUnsignedIntegerType() &&
3361  CGF.SanOpts.has(SanitizerKind::UnsignedIntegerOverflow) &&
3362  !CanElideOverflowCheck(CGF.getContext(), op))
3363  return EmitOverflowCheckedBinOp(op);
3364 
3365  if (op.LHS->getType()->isFPOrFPVectorTy()) {
3366  // Try to form an fmuladd.
3367  if (Value *FMulAdd = tryEmitFMulAdd(op, CGF, Builder))
3368  return FMulAdd;
3369 
3370  Value *V = Builder.CreateFAdd(op.LHS, op.RHS, "add");
3371  return propagateFMFlags(V, op);
3372  }
3373 
3374  if (op.isFixedPointBinOp())
3375  return EmitFixedPointBinOp(op);
3376 
3377  return Builder.CreateAdd(op.LHS, op.RHS, "add");
3378 }
3379 
3380 /// The resulting value must be calculated with exact precision, so the operands
3381 /// may not be the same type.
3382 Value *ScalarExprEmitter::EmitFixedPointBinOp(const BinOpInfo &op) {
3383  using llvm::APSInt;
3384  using llvm::ConstantInt;
3385 
3386  const auto *BinOp = cast<BinaryOperator>(op.E);
3387 
3388  // The result is a fixed point type and at least one of the operands is fixed
3389  // point while the other is either fixed point or an int. This resulting type
3390  // should be determined by Sema::handleFixedPointConversions().
3391  QualType ResultTy = op.Ty;
3392  QualType LHSTy = BinOp->getLHS()->getType();
3393  QualType RHSTy = BinOp->getRHS()->getType();
3394  ASTContext &Ctx = CGF.getContext();
3395  Value *LHS = op.LHS;
3396  Value *RHS = op.RHS;
3397 
3398  auto LHSFixedSema = Ctx.getFixedPointSemantics(LHSTy);
3399  auto RHSFixedSema = Ctx.getFixedPointSemantics(RHSTy);
3400  auto ResultFixedSema = Ctx.getFixedPointSemantics(ResultTy);
3401  auto CommonFixedSema = LHSFixedSema.getCommonSemantics(RHSFixedSema);
3402 
3403  // Convert the operands to the full precision type.
3404  Value *FullLHS = EmitFixedPointConversion(LHS, LHSFixedSema, CommonFixedSema,
3405  BinOp->getExprLoc());
3406  Value *FullRHS = EmitFixedPointConversion(RHS, RHSFixedSema, CommonFixedSema,
3407  BinOp->getExprLoc());
3408 
3409  // Perform the actual addition.
3410  Value *Result;
3411  switch (BinOp->getOpcode()) {
3412  case BO_Add: {
3413  if (ResultFixedSema.isSaturated()) {
3414  llvm::Intrinsic::ID IID = ResultFixedSema.isSigned()
3415  ? llvm::Intrinsic::sadd_sat
3416  : llvm::Intrinsic::uadd_sat;
3417  Result = Builder.CreateBinaryIntrinsic(IID, FullLHS, FullRHS);
3418  } else {
3419  Result = Builder.CreateAdd(FullLHS, FullRHS);
3420  }
3421  break;
3422  }
3423  case BO_Sub: {
3424  if (ResultFixedSema.isSaturated()) {
3425  llvm::Intrinsic::ID IID = ResultFixedSema.isSigned()
3426  ? llvm::Intrinsic::ssub_sat
3427  : llvm::Intrinsic::usub_sat;
3428  Result = Builder.CreateBinaryIntrinsic(IID, FullLHS, FullRHS);
3429  } else {
3430  Result = Builder.CreateSub(FullLHS, FullRHS);
3431  }
3432  break;
3433  }
3434  case BO_LT:
3435  return CommonFixedSema.isSigned() ? Builder.CreateICmpSLT(FullLHS, FullRHS)
3436  : Builder.CreateICmpULT(FullLHS, FullRHS);
3437  case BO_GT:
3438  return CommonFixedSema.isSigned() ? Builder.CreateICmpSGT(FullLHS, FullRHS)
3439  : Builder.CreateICmpUGT(FullLHS, FullRHS);
3440  case BO_LE:
3441  return CommonFixedSema.isSigned() ? Builder.CreateICmpSLE(FullLHS, FullRHS)
3442  : Builder.CreateICmpULE(FullLHS, FullRHS);
3443  case BO_GE:
3444  return CommonFixedSema.isSigned() ? Builder.CreateICmpSGE(FullLHS, FullRHS)
3445  : Builder.CreateICmpUGE(FullLHS, FullRHS);
3446  case BO_EQ:
3447  // For equality operations, we assume any padding bits on unsigned types are
3448  // zero'd out. They could be overwritten through non-saturating operations
3449  // that cause overflow, but this leads to undefined behavior.
3450  return Builder.CreateICmpEQ(FullLHS, FullRHS);
3451  case BO_NE:
3452  return Builder.CreateICmpNE(FullLHS, FullRHS);
3453  case BO_Mul:
3454  case BO_Div:
3455  case BO_Shl:
3456  case BO_Shr:
3457  case BO_Cmp:
3458  case BO_LAnd:
3459  case BO_LOr:
3460  case BO_MulAssign:
3461  case BO_DivAssign:
3462  case BO_AddAssign:
3463  case BO_SubAssign:
3464  case BO_ShlAssign:
3465  case BO_ShrAssign:
3466  llvm_unreachable("Found unimplemented fixed point binary operation");
3467  case BO_PtrMemD:
3468  case BO_PtrMemI:
3469  case BO_Rem:
3470  case BO_Xor:
3471  case BO_And:
3472  case BO_Or:
3473  case BO_Assign:
3474  case BO_RemAssign:
3475  case BO_AndAssign:
3476  case BO_XorAssign:
3477  case BO_OrAssign:
3478  case BO_Comma:
3479  llvm_unreachable("Found unsupported binary operation for fixed point types.");
3480  }
3481 
3482  // Convert to the result type.
3483  return EmitFixedPointConversion(Result, CommonFixedSema, ResultFixedSema,
3484  BinOp->getExprLoc());
3485 }
3486 
3487 Value *ScalarExprEmitter::EmitSub(const BinOpInfo &op) {
3488  // The LHS is always a pointer if either side is.
3489  if (!op.LHS->getType()->isPointerTy()) {
3490  if (op.Ty->isSignedIntegerOrEnumerationType()) {
3491  switch (CGF.getLangOpts().getSignedOverflowBehavior()) {
3493  return Builder.CreateSub(op.LHS, op.RHS, "sub");
3495  if (!CGF.SanOpts.has(SanitizerKind::SignedIntegerOverflow))
3496  return Builder.CreateNSWSub(op.LHS, op.RHS, "sub");
3497  LLVM_FALLTHROUGH;
3499  if (CanElideOverflowCheck(CGF.getContext(), op))
3500  return Builder.CreateNSWSub(op.LHS, op.RHS, "sub");
3501  return EmitOverflowCheckedBinOp(op);
3502  }
3503  }
3504 
3505  if (op.Ty->isUnsignedIntegerType() &&
3506  CGF.SanOpts.has(SanitizerKind::UnsignedIntegerOverflow) &&
3507  !CanElideOverflowCheck(CGF.getContext(), op))
3508  return EmitOverflowCheckedBinOp(op);
3509 
3510  if (op.LHS->getType()->isFPOrFPVectorTy()) {
3511  // Try to form an fmuladd.
3512  if (Value *FMulAdd = tryEmitFMulAdd(op, CGF, Builder, true))
3513  return FMulAdd;
3514  Value *V = Builder.CreateFSub(op.LHS, op.RHS, "sub");
3515  return propagateFMFlags(V, op);
3516  }
3517 
3518  if (op.isFixedPointBinOp())
3519  return EmitFixedPointBinOp(op);
3520 
3521  return Builder.CreateSub(op.LHS, op.RHS, "sub");
3522  }
3523 
3524  // If the RHS is not a pointer, then we have normal pointer
3525  // arithmetic.
3526  if (!op.RHS->getType()->isPointerTy())
3528 
3529  // Otherwise, this is a pointer subtraction.
3530 
3531  // Do the raw subtraction part.
3532  llvm::Value *LHS
3533  = Builder.CreatePtrToInt(op.LHS, CGF.PtrDiffTy, "sub.ptr.lhs.cast");
3534  llvm::Value *RHS
3535  = Builder.CreatePtrToInt(op.RHS, CGF.PtrDiffTy, "sub.ptr.rhs.cast");
3536  Value *diffInChars = Builder.CreateSub(LHS, RHS, "sub.ptr.sub");
3537 
3538  // Okay, figure out the element size.
3539  const BinaryOperator *expr = cast<BinaryOperator>(op.E);
3540  QualType elementType = expr->getLHS()->getType()->getPointeeType();
3541 
3542  llvm::Value *divisor = nullptr;
3543 
3544  // For a variable-length array, this is going to be non-constant.
3545  if (const VariableArrayType *vla
3546  = CGF.getContext().getAsVariableArrayType(elementType)) {
3547  auto VlaSize = CGF.getVLASize(vla);
3548  elementType = VlaSize.Type;
3549  divisor = VlaSize.NumElts;
3550 
3551  // Scale the number of non-VLA elements by the non-VLA element size.
3552  CharUnits eltSize = CGF.getContext().getTypeSizeInChars(elementType);
3553  if (!eltSize.isOne())
3554  divisor = CGF.Builder.CreateNUWMul(CGF.CGM.getSize(eltSize), divisor);
3555 
3556  // For everything elese, we can just compute it, safe in the
3557  // assumption that Sema won't let anything through that we can't
3558  // safely compute the size of.
3559  } else {
3560  CharUnits elementSize;
3561  // Handle GCC extension for pointer arithmetic on void* and
3562  // function pointer types.
3563  if (elementType->isVoidType() || elementType->isFunctionType())
3564  elementSize = CharUnits::One();
3565  else
3566  elementSize = CGF.getContext().getTypeSizeInChars(elementType);
3567 
3568  // Don't even emit the divide for element size of 1.
3569  if (elementSize.isOne())
3570  return diffInChars;
3571 
3572  divisor = CGF.CGM.getSize(elementSize);
3573  }
3574 
3575  // Otherwise, do a full sdiv. This uses the "exact" form of sdiv, since
3576  // pointer difference in C is only defined in the case where both operands
3577  // are pointing to elements of an array.
3578  return Builder.CreateExactSDiv(diffInChars, divisor, "sub.ptr.div");
3579 }
3580 
3581 Value *ScalarExprEmitter::GetWidthMinusOneValue(Value* LHS,Value* RHS) {
3582  llvm::IntegerType *Ty;
3583  if (llvm::VectorType *VT = dyn_cast<llvm::VectorType>(LHS->getType()))
3584  Ty = cast<llvm::IntegerType>(VT->getElementType());
3585  else
3586  Ty = cast<llvm::IntegerType>(LHS->getType());
3587  return llvm::ConstantInt::get(RHS->getType(), Ty->getBitWidth() - 1);
3588 }
3589 
3590 Value *ScalarExprEmitter::EmitShl(const BinOpInfo &Ops) {
3591  // LLVM requires the LHS and RHS to be the same type: promote or truncate the
3592  // RHS to the same size as the LHS.
3593  Value *RHS = Ops.RHS;
3594  if (Ops.LHS->getType() != RHS->getType())
3595  RHS = Builder.CreateIntCast(RHS, Ops.LHS->getType(), false, "sh_prom");
3596 
3597  bool SanitizeBase = CGF.SanOpts.has(SanitizerKind::ShiftBase) &&
3598  Ops.Ty->hasSignedIntegerRepresentation() &&
3600  !CGF.getLangOpts().CPlusPlus2a;
3601  bool SanitizeExponent = CGF.SanOpts.has(SanitizerKind::ShiftExponent);
3602  // OpenCL 6.3j: shift values are effectively % word size of LHS.
3603  if (CGF.getLangOpts().OpenCL)
3604  RHS =
3605  Builder.CreateAnd(RHS, GetWidthMinusOneValue(Ops.LHS, RHS), "shl.mask");
3606  else if ((SanitizeBase || SanitizeExponent) &&
3607  isa<llvm::IntegerType>(Ops.LHS->getType())) {
3608  CodeGenFunction::SanitizerScope SanScope(&CGF);
3610  llvm::Value *WidthMinusOne = GetWidthMinusOneValue(Ops.LHS, Ops.RHS);
3611  llvm::Value *ValidExponent = Builder.CreateICmpULE(Ops.RHS, WidthMinusOne);
3612 
3613  if (SanitizeExponent) {
3614  Checks.push_back(
3615  std::make_pair(ValidExponent, SanitizerKind::ShiftExponent));
3616  }
3617 
3618  if (SanitizeBase) {
3619  // Check whether we are shifting any non-zero bits off the top of the
3620  // integer. We only emit this check if exponent is valid - otherwise
3621  // instructions below will have undefined behavior themselves.
3622  llvm::BasicBlock *Orig = Builder.GetInsertBlock();
3623  llvm::BasicBlock *Cont = CGF.createBasicBlock("cont");
3624  llvm::BasicBlock *CheckShiftBase = CGF.createBasicBlock("check");
3625  Builder.CreateCondBr(ValidExponent, CheckShiftBase, Cont);
3626  llvm::Value *PromotedWidthMinusOne =
3627  (RHS == Ops.RHS) ? WidthMinusOne
3628  : GetWidthMinusOneValue(Ops.LHS, RHS);
3629  CGF.EmitBlock(CheckShiftBase);
3630  llvm::Value *BitsShiftedOff = Builder.CreateLShr(
3631  Ops.LHS, Builder.CreateSub(PromotedWidthMinusOne, RHS, "shl.zeros",
3632  /*NUW*/ true, /*NSW*/ true),
3633  "shl.check");
3634  if (CGF.getLangOpts().CPlusPlus) {
3635  // In C99, we are not permitted to shift a 1 bit into the sign bit.
3636  // Under C++11's rules, shifting a 1 bit into the sign bit is
3637  // OK, but shifting a 1 bit out of it is not. (C89 and C++03 don't
3638  // define signed left shifts, so we use the C99 and C++11 rules there).
3639  llvm::Value *One = llvm::ConstantInt::get(BitsShiftedOff->getType(), 1);
3640  BitsShiftedOff = Builder.CreateLShr(BitsShiftedOff, One);
3641  }
3642  llvm::Value *Zero = llvm::ConstantInt::get(BitsShiftedOff->getType(), 0);
3643  llvm::Value *ValidBase = Builder.CreateICmpEQ(BitsShiftedOff, Zero);
3644  CGF.EmitBlock(Cont);
3645  llvm::PHINode *BaseCheck = Builder.CreatePHI(ValidBase->getType(), 2);
3646  BaseCheck->addIncoming(Builder.getTrue(), Orig);
3647  BaseCheck->addIncoming(ValidBase, CheckShiftBase);
3648  Checks.push_back(std::make_pair(BaseCheck, SanitizerKind::ShiftBase));
3649  }
3650 
3651  assert(!Checks.empty());
3652  EmitBinOpCheck(Checks, Ops);
3653  }
3654 
3655  return Builder.CreateShl(Ops.LHS, RHS, "shl");
3656 }
3657 
3658 Value *ScalarExprEmitter::EmitShr(const BinOpInfo &Ops) {
3659  // LLVM requires the LHS and RHS to be the same type: promote or truncate the
3660  // RHS to the same size as the LHS.
3661  Value *RHS = Ops.RHS;
3662  if (Ops.LHS->getType() != RHS->getType())
3663  RHS = Builder.CreateIntCast(RHS, Ops.LHS->getType(), false, "sh_prom");
3664 
3665  // OpenCL 6.3j: shift values are effectively % word size of LHS.
3666  if (CGF.getLangOpts().OpenCL)
3667  RHS =
3668  Builder.CreateAnd(RHS, GetWidthMinusOneValue(Ops.LHS, RHS), "shr.mask");
3669  else if (CGF.SanOpts.has(SanitizerKind::ShiftExponent) &&
3670  isa<llvm::IntegerType>(Ops.LHS->getType())) {
3671  CodeGenFunction::SanitizerScope SanScope(&CGF);
3672  llvm::Value *Valid =
3673  Builder.CreateICmpULE(RHS, GetWidthMinusOneValue(Ops.LHS, RHS));
3674  EmitBinOpCheck(std::make_pair(Valid, SanitizerKind::ShiftExponent), Ops);
3675  }
3676 
3677  if (Ops.Ty->hasUnsignedIntegerRepresentation())
3678  return Builder.CreateLShr(Ops.LHS, RHS, "shr");
3679  return Builder.CreateAShr(Ops.LHS, RHS, "shr");
3680 }
3681 
3683 // return corresponding comparison intrinsic for given vector type
3685  BuiltinType::Kind ElemKind) {
3686  switch (ElemKind) {
3687  default: llvm_unreachable("unexpected element type");
3688  case BuiltinType::Char_U:
3689  case BuiltinType::UChar:
3690  return (IT == VCMPEQ) ? llvm::Intrinsic::ppc_altivec_vcmpequb_p :
3691  llvm::Intrinsic::ppc_altivec_vcmpgtub_p;
3692  case BuiltinType::Char_S:
3693  case BuiltinType::SChar:
3694  return (IT == VCMPEQ) ? llvm::Intrinsic::ppc_altivec_vcmpequb_p :
3695  llvm::Intrinsic::ppc_altivec_vcmpgtsb_p;
3696  case BuiltinType::UShort:
3697  return (IT == VCMPEQ) ? llvm::Intrinsic::ppc_altivec_vcmpequh_p :
3698  llvm::Intrinsic::ppc_altivec_vcmpgtuh_p;
3699  case BuiltinType::Short:
3700  return (IT == VCMPEQ) ? llvm::Intrinsic::ppc_altivec_vcmpequh_p :
3701  llvm::Intrinsic::ppc_altivec_vcmpgtsh_p;
3702  case BuiltinType::UInt:
3703  return (IT == VCMPEQ) ? llvm::Intrinsic::ppc_altivec_vcmpequw_p :
3704  llvm::Intrinsic::ppc_altivec_vcmpgtuw_p;
3705  case BuiltinType::Int:
3706  return (IT == VCMPEQ) ? llvm::Intrinsic::ppc_altivec_vcmpequw_p :
3707  llvm::Intrinsic::ppc_altivec_vcmpgtsw_p;
3708  case BuiltinType::ULong:
3709  case BuiltinType::ULongLong:
3710  return (IT == VCMPEQ) ? llvm::Intrinsic::ppc_altivec_vcmpequd_p :
3711  llvm::Intrinsic::ppc_altivec_vcmpgtud_p;
3712  case BuiltinType::Long:
3713  case BuiltinType::LongLong:
3714  return (IT == VCMPEQ) ? llvm::Intrinsic::ppc_altivec_vcmpequd_p :
3715  llvm::Intrinsic::ppc_altivec_vcmpgtsd_p;
3716  case BuiltinType::Float:
3717  return (IT == VCMPEQ) ? llvm::Intrinsic::ppc_altivec_vcmpeqfp_p :
3718  llvm::Intrinsic::ppc_altivec_vcmpgtfp_p;
3719  case BuiltinType::Double:
3720  return (IT == VCMPEQ) ? llvm::Intrinsic::ppc_vsx_xvcmpeqdp_p :
3721  llvm::Intrinsic::ppc_vsx_xvcmpgtdp_p;
3722  }
3723 }
3724 
3726  llvm::CmpInst::Predicate UICmpOpc,
3727  llvm::CmpInst::Predicate SICmpOpc,
3728  llvm::CmpInst::Predicate FCmpOpc) {
3729  TestAndClearIgnoreResultAssign();
3730  Value *Result;
3731  QualType LHSTy = E->getLHS()->getType();
3732  QualType RHSTy = E->getRHS()->getType();
3733  if (const MemberPointerType *MPT = LHSTy->getAs<MemberPointerType>()) {
3734  assert(E->getOpcode() == BO_EQ ||
3735  E->getOpcode() == BO_NE);
3736  Value *LHS = CGF.EmitScalarExpr(E->getLHS());
3737  Value *RHS = CGF.EmitScalarExpr(E->getRHS());
3738  Result = CGF.CGM.getCXXABI().EmitMemberPointerComparison(
3739  CGF, LHS, RHS, MPT, E->getOpcode() == BO_NE);
3740  } else if (!LHSTy->isAnyComplexType() && !RHSTy->isAnyComplexType()) {
3741  BinOpInfo BOInfo = EmitBinOps(E);
3742  Value *LHS = BOInfo.LHS;
3743  Value *RHS = BOInfo.RHS;
3744 
3745  // If AltiVec, the comparison results in a numeric type, so we use
3746  // intrinsics comparing vectors and giving 0 or 1 as a result
3747  if (LHSTy->isVectorType() && !E->getType()->isVectorType()) {
3748  // constants for mapping CR6 register bits to predicate result
3749  enum { CR6_EQ=0, CR6_EQ_REV, CR6_LT, CR6_LT_REV } CR6;
3750 
3751  llvm::Intrinsic::ID ID = llvm::Intrinsic::not_intrinsic;
3752 
3753  // in several cases vector arguments order will be reversed
3754  Value *FirstVecArg = LHS,
3755  *SecondVecArg = RHS;
3756 
3757  QualType ElTy = LHSTy->castAs<VectorType>()->getElementType();
3758  const BuiltinType *BTy = ElTy->getAs<BuiltinType>();
3759  BuiltinType::Kind ElementKind = BTy->getKind();
3760 
3761  switch(E->getOpcode()) {
3762  default: llvm_unreachable("is not a comparison operation");
3763  case BO_EQ:
3764  CR6 = CR6_LT;
3765  ID = GetIntrinsic(VCMPEQ, ElementKind);
3766  break;
3767  case BO_NE:
3768  CR6 = CR6_EQ;
3769  ID = GetIntrinsic(VCMPEQ, ElementKind);
3770  break;
3771  case BO_LT:
3772  CR6 = CR6_LT;
3773  ID = GetIntrinsic(VCMPGT, ElementKind);
3774  std::swap(FirstVecArg, SecondVecArg);
3775  break;
3776  case BO_GT:
3777  CR6 = CR6_LT;
3778  ID = GetIntrinsic(VCMPGT, ElementKind);
3779  break;
3780  case BO_LE:
3781  if (ElementKind == BuiltinType::Float) {
3782  CR6 = CR6_LT;
3783  ID = llvm::Intrinsic::ppc_altivec_vcmpgefp_p;
3784  std::swap(FirstVecArg, SecondVecArg);
3785  }
3786  else {
3787  CR6 = CR6_EQ;
3788  ID = GetIntrinsic(VCMPGT, ElementKind);
3789  }
3790  break;
3791  case BO_GE:
3792  if (ElementKind == BuiltinType::Float) {
3793  CR6 = CR6_LT;
3794  ID = llvm::Intrinsic::ppc_altivec_vcmpgefp_p;
3795  }
3796  else {
3797  CR6 = CR6_EQ;
3798  ID = GetIntrinsic(VCMPGT, ElementKind);
3799  std::swap(FirstVecArg, SecondVecArg);
3800  }
3801  break;
3802  }
3803 
3804  Value *CR6Param = Builder.getInt32(CR6);
3805  llvm::Function *F = CGF.CGM.getIntrinsic(ID);
3806  Result = Builder.CreateCall(F, {CR6Param, FirstVecArg, SecondVecArg});
3807 
3808  // The result type of intrinsic may not be same as E->getType().
3809  // If E->getType() is not BoolTy, EmitScalarConversion will do the
3810  // conversion work. If E->getType() is BoolTy, EmitScalarConversion will
3811  // do nothing, if ResultTy is not i1 at the same time, it will cause
3812  // crash later.
3813  llvm::IntegerType *ResultTy = cast<llvm::IntegerType>(Result->getType());
3814  if (ResultTy->getBitWidth() > 1 &&
3815  E->getType() == CGF.getContext().BoolTy)
3816  Result = Builder.CreateTrunc(Result, Builder.getInt1Ty());
3817  return EmitScalarConversion(Result, CGF.getContext().BoolTy, E->getType(),
3818  E->getExprLoc());
3819  }
3820 
3821  if (BOInfo.isFixedPointBinOp()) {
3822  Result = EmitFixedPointBinOp(BOInfo);
3823  } else if (LHS->getType()->isFPOrFPVectorTy()) {
3824  Result = Builder.CreateFCmp(FCmpOpc, LHS, RHS, "cmp");
3825  } else if (LHSTy->hasSignedIntegerRepresentation()) {
3826  Result = Builder.CreateICmp(SICmpOpc, LHS, RHS, "cmp");
3827  } else {
3828  // Unsigned integers and pointers.
3829 
3830  if (CGF.CGM.getCodeGenOpts().StrictVTablePointers &&
3831  !isa<llvm::ConstantPointerNull>(LHS) &&
3832  !isa<llvm::ConstantPointerNull>(RHS)) {
3833 
3834  // Dynamic information is required to be stripped for comparisons,
3835  // because it could leak the dynamic information. Based on comparisons
3836  // of pointers to dynamic objects, the optimizer can replace one pointer
3837  // with another, which might be incorrect in presence of invariant
3838  // groups. Comparison with null is safe because null does not carry any
3839  // dynamic information.
3840  if (LHSTy.mayBeDynamicClass())
3841  LHS = Builder.CreateStripInvariantGroup(LHS);
3842  if (RHSTy.mayBeDynamicClass())
3843  RHS = Builder.CreateStripInvariantGroup(RHS);
3844  }
3845 
3846  Result = Builder.CreateICmp(UICmpOpc, LHS, RHS, "cmp");
3847  }
3848 
3849  // If this is a vector comparison, sign extend the result to the appropriate
3850  // vector integer type and return it (don't convert to bool).
3851  if (LHSTy->isVectorType())
3852  return Builder.CreateSExt(Result, ConvertType(E->getType()), "sext");
3853 
3854  } else {
3855  // Complex Comparison: can only be an equality comparison.
3857  QualType CETy;
3858  if (auto *CTy = LHSTy->getAs<ComplexType>()) {
3859  LHS = CGF.EmitComplexExpr(E->getLHS());
3860  CETy = CTy->getElementType();
3861  } else {
3862  LHS.first = Visit(E->getLHS());
3863  LHS.second = llvm::Constant::getNullValue(LHS.first->getType());
3864  CETy = LHSTy;
3865  }
3866  if (auto *CTy = RHSTy->getAs<ComplexType>()) {
3867  RHS = CGF.EmitComplexExpr(E->getRHS());
3868  assert(CGF.getContext().hasSameUnqualifiedType(CETy,
3869  CTy->getElementType()) &&
3870  "The element types must always match.");
3871  (void)CTy;
3872  } else {
3873  RHS.first = Visit(E->getRHS());
3874  RHS.second = llvm::Constant::getNullValue(RHS.first->getType());
3875  assert(CGF.getContext().hasSameUnqualifiedType(CETy, RHSTy) &&
3876  "The element types must always match.");
3877  }
3878 
3879  Value *ResultR, *ResultI;
3880  if (CETy->isRealFloatingType()) {
3881  ResultR = Builder.CreateFCmp(FCmpOpc, LHS.first, RHS.first, "cmp.r");
3882  ResultI = Builder.CreateFCmp(FCmpOpc, LHS.second, RHS.second, "cmp.i");
3883  } else {
3884  // Complex comparisons can only be equality comparisons. As such, signed
3885  // and unsigned opcodes are the same.
3886  ResultR = Builder.CreateICmp(UICmpOpc, LHS.first, RHS.first, "cmp.r");
3887  ResultI = Builder.CreateICmp(UICmpOpc, LHS.second, RHS.second, "cmp.i");
3888  }
3889 
3890  if (E->getOpcode() == BO_EQ) {
3891  Result = Builder.CreateAnd(ResultR, ResultI, "and.ri");
3892  } else {
3893  assert(E->getOpcode() == BO_NE &&
3894  "Complex comparison other than == or != ?");
3895  Result = Builder.CreateOr(ResultR, ResultI, "or.ri");
3896  }
3897  }
3898 
3899  return EmitScalarConversion(Result, CGF.getContext().BoolTy, E->getType(),
3900  E->getExprLoc());
3901 }
3902 
3903 Value *ScalarExprEmitter::VisitBinAssign(const BinaryOperator *E) {
3904  bool Ignore = TestAndClearIgnoreResultAssign();
3905 
3906  Value *RHS;
3907  LValue LHS;
3908 
3909  switch (E->getLHS()->getType().getObjCLifetime()) {
3911  std::tie(LHS, RHS) = CGF.EmitARCStoreStrong(E, Ignore);
3912  break;
3913 
3915  std::tie(LHS, RHS) = CGF.EmitARCStoreAutoreleasing(E);
3916  break;
3917 
3919  std::tie(LHS, RHS) = CGF.EmitARCStoreUnsafeUnretained(E, Ignore);
3920  break;
3921 
3922  case Qualifiers::OCL_Weak:
3923  RHS = Visit(E->getRHS());
3924  LHS = EmitCheckedLValue(E->getLHS(), CodeGenFunction::TCK_Store);
3925  RHS = CGF.EmitARCStoreWeak(LHS.getAddress(), RHS, Ignore);
3926  break;
3927 
3928  case Qualifiers::OCL_None:
3929  // __block variables need to have the rhs evaluated first, plus
3930  // this should improve codegen just a little.
3931  RHS = Visit(E->getRHS());
3932  LHS = EmitCheckedLValue(E->getLHS(), CodeGenFunction::TCK_Store);
3933 
3934  // Store the value into the LHS. Bit-fields are handled specially
3935  // because the result is altered by the store, i.e., [C99 6.5.16p1]
3936  // 'An assignment expression has the value of the left operand after
3937  // the assignment...'.
3938  if (LHS.isBitField()) {
3939  CGF.EmitStoreThroughBitfieldLValue(RValue::get(RHS), LHS, &RHS);
3940  } else {
3941  CGF.EmitNullabilityCheck(LHS, RHS, E->getExprLoc());
3942  CGF.EmitStoreThroughLValue(RValue::get(RHS), LHS);
3943  }
3944  }
3945 
3946  // If the result is clearly ignored, return now.
3947  if (Ignore)
3948  return nullptr;
3949 
3950  // The result of an assignment in C is the assigned r-value.
3951  if (!CGF.getLangOpts().CPlusPlus)
3952  return RHS;
3953 
3954  // If the lvalue is non-volatile, return the computed value of the assignment.
3955  if (!LHS.isVolatileQualified())
3956  return RHS;
3957 
3958  // Otherwise, reload the value.
3959  return EmitLoadOfLValue(LHS, E->getExprLoc());
3960 }
3961 
3962 Value *ScalarExprEmitter::VisitBinLAnd(const BinaryOperator *E) {
3963  // Perform vector logical and on comparisons with zero vectors.
3964  if (E->getType()->isVectorType()) {
3965  CGF.incrementProfileCounter(E);
3966 
3967  Value *LHS = Visit(E->getLHS());
3968  Value *RHS = Visit(E->getRHS());
3969  Value *Zero = llvm::ConstantAggregateZero::get(LHS->getType());
3970  if (LHS->getType()->isFPOrFPVectorTy()) {
3971  LHS = Builder.CreateFCmp(llvm::CmpInst::FCMP_UNE, LHS, Zero, "cmp");
3972  RHS = Builder.CreateFCmp(llvm::CmpInst::FCMP_UNE, RHS, Zero, "cmp");
3973  } else {
3974  LHS = Builder.CreateICmp(llvm::CmpInst::ICMP_NE, LHS, Zero, "cmp");
3975  RHS = Builder.CreateICmp(llvm::CmpInst::ICMP_NE, RHS, Zero, "cmp");
3976  }
3977  Value *And = Builder.CreateAnd(LHS, RHS);
3978  return Builder.CreateSExt(And, ConvertType(E->getType()), "sext");
3979  }
3980 
3981  llvm::Type *ResTy = ConvertType(E->getType());
3982 
3983  // If we have 0 && RHS, see if we can elide RHS, if so, just return 0.
3984  // If we have 1 && X, just emit X without inserting the control flow.
3985  bool LHSCondVal;
3986  if (CGF.ConstantFoldsToSimpleInteger(E->getLHS(), LHSCondVal)) {
3987  if (LHSCondVal) { // If we have 1 && X, just emit X.
3988  CGF.incrementProfileCounter(E);
3989 
3990  Value *RHSCond = CGF.EvaluateExprAsBool(E->getRHS());
3991  // ZExt result to int or bool.
3992  return Builder.CreateZExtOrBitCast(RHSCond, ResTy, "land.ext");
3993  }
3994 
3995  // 0 && RHS: If it is safe, just elide the RHS, and return 0/false.
3996  if (!CGF.ContainsLabel(E->getRHS()))
3997  return llvm::Constant::getNullValue(ResTy);
3998  }
3999 
4000  llvm::BasicBlock *ContBlock = CGF.createBasicBlock("land.end");
4001  llvm::BasicBlock *RHSBlock = CGF.createBasicBlock("land.rhs");
4002 
4004 
4005  // Branch on the LHS first. If it is false, go to the failure (cont) block.
4006  CGF.EmitBranchOnBoolExpr(E->getLHS(), RHSBlock, ContBlock,
4007  CGF.getProfileCount(E->getRHS()));
4008 
4009  // Any edges into the ContBlock are now from an (indeterminate number of)
4010  // edges from this first condition. All of these values will be false. Start
4011  // setting up the PHI node in the Cont Block for this.
4012  llvm::PHINode *PN = llvm::PHINode::Create(llvm::Type::getInt1Ty(VMContext), 2,
4013  "", ContBlock);
4014  for (llvm::pred_iterator PI = pred_begin(ContBlock), PE = pred_end(ContBlock);
4015  PI != PE; ++PI)
4016  PN->addIncoming(llvm::ConstantInt::getFalse(VMContext), *PI);
4017 
4018  eval.begin(CGF);
4019  CGF.EmitBlock(RHSBlock);
4020  CGF.incrementProfileCounter(E);
4021  Value *RHSCond = CGF.EvaluateExprAsBool(E->getRHS());
4022  eval.end(CGF);
4023 
4024  // Reaquire the RHS block, as there may be subblocks inserted.
4025  RHSBlock = Builder.GetInsertBlock();
4026 
4027  // Emit an unconditional branch from this block to ContBlock.
4028  {
4029  // There is no need to emit line number for unconditional branch.
4030  auto NL = ApplyDebugLocation::CreateEmpty(CGF);
4031  CGF.EmitBlock(ContBlock);
4032  }
4033  // Insert an entry into the phi node for the edge with the value of RHSCond.
4034  PN->addIncoming(RHSCond, RHSBlock);
4035 
4036  // Artificial location to preserve the scope information
4037  {
4038  auto NL = ApplyDebugLocation::CreateArtificial(CGF);
4039  PN->setDebugLoc(Builder.getCurrentDebugLocation());
4040  }
4041 
4042  // ZExt result to int.
4043  return Builder.CreateZExtOrBitCast(PN, ResTy, "land.ext");
4044 }
4045 
4046 Value *ScalarExprEmitter::VisitBinLOr(const BinaryOperator *E) {
4047  // Perform vector logical or on comparisons with zero vectors.
4048  if (E->getType()->isVectorType()) {
4049  CGF.incrementProfileCounter(E);
4050 
4051  Value *LHS = Visit(E->getLHS());
4052  Value *RHS = Visit(E->getRHS());
4053  Value *Zero = llvm::ConstantAggregateZero::get(LHS->getType());
4054  if (LHS->getType()->isFPOrFPVectorTy()) {
4055  LHS = Builder.CreateFCmp(llvm::CmpInst::FCMP_UNE, LHS, Zero, "cmp");
4056  RHS = Builder.CreateFCmp(llvm::CmpInst::FCMP_UNE, RHS, Zero, "cmp");
4057  } else {
4058  LHS = Builder.CreateICmp(llvm::CmpInst::ICMP_NE, LHS, Zero, "cmp");
4059  RHS = Builder.CreateICmp(llvm::CmpInst::ICMP_NE, RHS, Zero, "cmp");
4060  }
4061  Value *Or = Builder.CreateOr(LHS, RHS);
4062  return Builder.CreateSExt(Or, ConvertType(E->getType()), "sext");
4063  }
4064 
4065  llvm::Type *ResTy = ConvertType(E->getType());
4066 
4067  // If we have 1 || RHS, see if we can elide RHS, if so, just return 1.
4068  // If we have 0 || X, just emit X without inserting the control flow.
4069  bool LHSCondVal;
4070  if (CGF.ConstantFoldsToSimpleInteger(E->getLHS(), LHSCondVal)) {
4071  if (!LHSCondVal) { // If we have 0 || X, just emit X.
4072  CGF.incrementProfileCounter(E);
4073 
4074  Value *RHSCond = CGF.EvaluateExprAsBool(E->getRHS());
4075  // ZExt result to int or bool.
4076  return Builder.CreateZExtOrBitCast(RHSCond, ResTy, "lor.ext");
4077  }
4078 
4079  // 1 || RHS: If it is safe, just elide the RHS, and return 1/true.
4080  if (!CGF.ContainsLabel(E->getRHS()))
4081  return llvm::ConstantInt::get(ResTy, 1);
4082  }
4083 
4084  llvm::BasicBlock *ContBlock = CGF.createBasicBlock("lor.end");
4085  llvm::BasicBlock *RHSBlock = CGF.createBasicBlock("lor.rhs");
4086 
4088 
4089  // Branch on the LHS first. If it is true, go to the success (cont) block.
4090  CGF.EmitBranchOnBoolExpr(E->getLHS(), ContBlock, RHSBlock,
4091  CGF.getCurrentProfileCount() -
4092  CGF.getProfileCount(E->getRHS()));
4093 
4094  // Any edges into the ContBlock are now from an (indeterminate number of)
4095  // edges from this first condition. All of these values will be true. Start
4096  // setting up the PHI node in the Cont Block for this.
4097  llvm::PHINode *PN = llvm::PHINode::Create(llvm::Type::getInt1Ty(VMContext), 2,
4098  "", ContBlock);
4099  for (llvm::pred_iterator PI = pred_begin(ContBlock), PE = pred_end(ContBlock);
4100  PI != PE; ++PI)
4101  PN->addIncoming(llvm::ConstantInt::getTrue(VMContext), *PI);
4102 
4103  eval.begin(CGF);
4104 
4105  // Emit the RHS condition as a bool value.
4106  CGF.EmitBlock(RHSBlock);
4107  CGF.incrementProfileCounter(E);
4108  Value *RHSCond = CGF.EvaluateExprAsBool(E->getRHS());
4109 
4110  eval.end(CGF);
4111 
4112  // Reaquire the RHS block, as there may be subblocks inserted.
4113  RHSBlock = Builder.GetInsertBlock();
4114 
4115  // Emit an unconditional branch from this block to ContBlock. Insert an entry
4116  // into the phi node for the edge with the value of RHSCond.
4117  CGF.EmitBlock(ContBlock);
4118  PN->addIncoming(RHSCond, RHSBlock);
4119 
4120  // ZExt result to int.
4121  return Builder.CreateZExtOrBitCast(PN, ResTy, "lor.ext");
4122 }
4123 
4124 Value *ScalarExprEmitter::VisitBinComma(const BinaryOperator *E) {
4125  CGF.EmitIgnoredExpr(E->getLHS());
4126  CGF.EnsureInsertPoint();
4127  return Visit(E->getRHS());
4128 }
4129 
4130 //===----------------------------------------------------------------------===//
4131 // Other Operators
4132 //===----------------------------------------------------------------------===//
4133 
4134 /// isCheapEnoughToEvaluateUnconditionally - Return true if the specified
4135 /// expression is cheap enough and side-effect-free enough to evaluate
4136 /// unconditionally instead of conditionally. This is used to convert control
4137 /// flow into selects in some cases.
4139  CodeGenFunction &CGF) {
4140  // Anything that is an integer or floating point constant is fine.
4141  return E->IgnoreParens()->isEvaluatable(CGF.getContext());
4142 
4143  // Even non-volatile automatic variables can't be evaluated unconditionally.
4144  // Referencing a thread_local may cause non-trivial initialization work to
4145  // occur. If we're inside a lambda and one of the variables is from the scope
4146  // outside the lambda, that function may have returned already. Reading its
4147  // locals is a bad idea. Also, these reads may introduce races there didn't
4148  // exist in the source-level program.
4149 }
4150 
4151 
4152 Value *ScalarExprEmitter::
4153 VisitAbstractConditionalOperator(const AbstractConditionalOperator *E) {
4154  TestAndClearIgnoreResultAssign();
4155 
4156  // Bind the common expression if necessary.
4157  CodeGenFunction::OpaqueValueMapping binding(CGF, E);
4158 
4159  Expr *condExpr = E->getCond();
4160  Expr *lhsExpr = E->getTrueExpr();
4161  Expr *rhsExpr = E->getFalseExpr();
4162 
4163  // If the condition constant folds and can be elided, try to avoid emitting
4164  // the condition and the dead arm.
4165  bool CondExprBool;
4166  if (CGF.ConstantFoldsToSimpleInteger(condExpr, CondExprBool)) {
4167  Expr *live = lhsExpr, *dead = rhsExpr;
4168  if (!CondExprBool) std::swap(live, dead);
4169 
4170  // If the dead side doesn't have labels we need, just emit the Live part.
4171  if (!CGF.ContainsLabel(dead)) {
4172  if (CondExprBool)
4173  CGF.incrementProfileCounter(E);
4174  Value *Result = Visit(live);
4175 
4176  // If the live part is a throw expression, it acts like it has a void
4177  // type, so evaluating it returns a null Value*. However, a conditional
4178  // with non-void type must return a non-null Value*.
4179  if (!Result && !E->getType()->isVoidType())
4180  Result = llvm::UndefValue::get(CGF.ConvertType(E->getType()));
4181 
4182  return Result;
4183  }
4184  }
4185 
4186  // OpenCL: If the condition is a vector, we can treat this condition like
4187  // the select function.
4188  if (CGF.getLangOpts().OpenCL
4189  && condExpr->getType()->isVectorType()) {
4190  CGF.incrementProfileCounter(E);
4191 
4192  llvm::Value *CondV = CGF.EmitScalarExpr(condExpr);
4193  llvm::Value *LHS = Visit(lhsExpr);
4194  llvm::Value *RHS = Visit(rhsExpr);
4195 
4196  llvm::Type *condType = ConvertType(condExpr->getType());
4197  llvm::VectorType *vecTy = cast<llvm::VectorType>(condType);
4198 
4199  unsigned numElem = vecTy->getNumElements();
4200  llvm::Type *elemType = vecTy->getElementType();
4201 
4202  llvm::Value *zeroVec = llvm::Constant::getNullValue(vecTy);
4203  llvm::Value *TestMSB = Builder.CreateICmpSLT(CondV, zeroVec);
4204  llvm::Value *tmp = Builder.CreateSExt(TestMSB,
4205  llvm::VectorType::get(elemType,
4206  numElem),
4207  "sext");
4208  llvm::Value *tmp2 = Builder.CreateNot(tmp);
4209 
4210  // Cast float to int to perform ANDs if necessary.
4211  llvm::Value *RHSTmp = RHS;
4212  llvm::Value *LHSTmp = LHS;
4213  bool wasCast = false;
4214  llvm::VectorType *rhsVTy = cast<llvm::VectorType>(RHS->getType());
4215  if (rhsVTy->getElementType()->isFloatingPointTy()) {
4216  RHSTmp = Builder.CreateBitCast(RHS, tmp2->getType());
4217  LHSTmp = Builder.CreateBitCast(LHS, tmp->getType());
4218  wasCast = true;
4219  }
4220 
4221  llvm::Value *tmp3 = Builder.CreateAnd(RHSTmp, tmp2);
4222  llvm::Value *tmp4 = Builder.CreateAnd(LHSTmp, tmp);
4223  llvm::Value *tmp5 = Builder.CreateOr(tmp3, tmp4, "cond");
4224  if (wasCast)
4225  tmp5 = Builder.CreateBitCast(tmp5, RHS->getType());
4226 
4227  return tmp5;
4228  }
4229 
4230  // If this is a really simple expression (like x ? 4 : 5), emit this as a
4231  // select instead of as control flow. We can only do this if it is cheap and
4232  // safe to evaluate the LHS and RHS unconditionally.
4233  if (isCheapEnoughToEvaluateUnconditionally(lhsExpr, CGF) &&
4235  llvm::Value *CondV = CGF.EvaluateExprAsBool(condExpr);
4236  llvm::Value *StepV = Builder.CreateZExtOrBitCast(CondV, CGF.Int64Ty);
4237 
4238  CGF.incrementProfileCounter(E, StepV);
4239 
4240  llvm::Value *LHS = Visit(lhsExpr);
4241  llvm::Value *RHS = Visit(rhsExpr);
4242  if (!LHS) {
4243  // If the conditional has void type, make sure we return a null Value*.
4244  assert(!RHS && "LHS and RHS types must match");
4245  return nullptr;
4246  }
4247  return Builder.CreateSelect(CondV, LHS, RHS, "cond");
4248  }
4249 
4250  llvm::BasicBlock *LHSBlock = CGF.createBasicBlock("cond.true");
4251  llvm::BasicBlock *RHSBlock = CGF.createBasicBlock("cond.false");
4252  llvm::BasicBlock *ContBlock = CGF.createBasicBlock("cond.end");
4253 
4255  CGF.EmitBranchOnBoolExpr(condExpr, LHSBlock, RHSBlock,
4256  CGF.getProfileCount(lhsExpr));
4257 
4258  CGF.EmitBlock(LHSBlock);
4259  CGF.incrementProfileCounter(E);
4260  eval.begin(CGF);
4261  Value *LHS = Visit(lhsExpr);
4262  eval.end(CGF);
4263 
4264  LHSBlock = Builder.GetInsertBlock();
4265  Builder.CreateBr(ContBlock);
4266 
4267  CGF.EmitBlock(RHSBlock);
4268  eval.begin(CGF);
4269  Value *RHS = Visit(rhsExpr);
4270  eval.end(CGF);
4271 
4272  RHSBlock = Builder.GetInsertBlock();
4273  CGF.EmitBlock(ContBlock);
4274 
4275  // If the LHS or RHS is a throw expression, it will be legitimately null.
4276  if (!LHS)
4277  return RHS;
4278  if (!RHS)
4279  return LHS;
4280 
4281  // Create a PHI node for the real part.
4282  llvm::PHINode *PN = Builder.CreatePHI(LHS->getType(), 2, "cond");
4283  PN->addIncoming(LHS, LHSBlock);
4284  PN->addIncoming(RHS, RHSBlock);
4285  return PN;
4286 }
4287 
4288 Value *ScalarExprEmitter::VisitChooseExpr(ChooseExpr *E) {
4289  return Visit(E->getChosenSubExpr());
4290 }
4291 
4292 Value *ScalarExprEmitter::VisitVAArgExpr(VAArgExpr *VE) {
4293  QualType Ty = VE->getType();
4294 
4295  if (Ty->isVariablyModifiedType())
4296  CGF.EmitVariablyModifiedType(Ty);
4297 
4298  Address ArgValue = Address::invalid();
4299  Address ArgPtr = CGF.EmitVAArg(VE, ArgValue);
4300 
4301  llvm::Type *ArgTy = ConvertType(VE->getType());
4302 
4303  // If EmitVAArg fails, emit an error.
4304  if (!ArgPtr.isValid()) {
4305  CGF.ErrorUnsupported(VE, "va_arg expression");
4306  return llvm::UndefValue::get(ArgTy);
4307  }
4308 
4309  // FIXME Volatility.
4310  llvm::Value *Val = Builder.CreateLoad(ArgPtr);
4311 
4312  // If EmitVAArg promoted the type, we must truncate it.
4313  if (ArgTy != Val->getType()) {
4314  if (ArgTy->isPointerTy() && !Val->getType()->isPointerTy())
4315  Val = Builder.CreateIntToPtr(Val, ArgTy);
4316  else
4317  Val = Builder.CreateTrunc(Val, ArgTy);
4318  }
4319 
4320  return Val;
4321 }
4322 
4323 Value *ScalarExprEmitter::VisitBlockExpr(const BlockExpr *block) {
4324  return CGF.EmitBlockLiteral(block);
4325 }
4326 
4327 // Convert a vec3 to vec4, or vice versa.
4329  Value *Src, unsigned NumElementsDst) {
4330  llvm::Value *UnV = llvm::UndefValue::get(Src->getType());
4332  Args.push_back(Builder.getInt32(0));
4333  Args.push_back(Builder.getInt32(1));
4334  Args.push_back(Builder.getInt32(2));
4335  if (NumElementsDst == 4)
4336  Args.push_back(llvm::UndefValue::get(CGF.Int32Ty));
4337  llvm::Constant *Mask = llvm::ConstantVector::get(Args);
4338  return Builder.CreateShuffleVector(Src, UnV, Mask);
4339 }
4340 
4341 // Create cast instructions for converting LLVM value \p Src to LLVM type \p
4342 // DstTy. \p Src has the same size as \p DstTy. Both are single value types
4343 // but could be scalar or vectors of different lengths, and either can be
4344 // pointer.
4345 // There are 4 cases:
4346 // 1. non-pointer -> non-pointer : needs 1 bitcast
4347 // 2. pointer -> pointer : needs 1 bitcast or addrspacecast
4348 // 3. pointer -> non-pointer
4349 // a) pointer -> intptr_t : needs 1 ptrtoint
4350 // b) pointer -> non-intptr_t : needs 1 ptrtoint then 1 bitcast
4351 // 4. non-pointer -> pointer
4352 // a) intptr_t -> pointer : needs 1 inttoptr
4353 // b) non-intptr_t -> pointer : needs 1 bitcast then 1 inttoptr
4354 // Note: for cases 3b and 4b two casts are required since LLVM casts do not
4355 // allow casting directly between pointer types and non-integer non-pointer
4356 // types.
4358  const llvm::DataLayout &DL,
4359  Value *Src, llvm::Type *DstTy,
4360  StringRef Name = "") {
4361  auto SrcTy = Src->getType();
4362 
4363  // Case 1.
4364  if (!SrcTy->isPointerTy() && !DstTy->isPointerTy())
4365  return Builder.CreateBitCast(Src, DstTy, Name);
4366 
4367  // Case 2.
4368  if (SrcTy->isPointerTy() && DstTy->isPointerTy())
4369  return Builder.CreatePointerBitCastOrAddrSpaceCast(Src, DstTy, Name);
4370 
4371  // Case 3.
4372  if (SrcTy->isPointerTy() && !DstTy->isPointerTy()) {
4373  // Case 3b.
4374  if (!DstTy->isIntegerTy())
4375  Src = Builder.CreatePtrToInt(Src, DL.getIntPtrType(SrcTy));
4376  // Cases 3a and 3b.
4377  return Builder.CreateBitOrPointerCast(Src, DstTy, Name);
4378  }
4379 
4380  // Case 4b.
4381  if (!SrcTy->isIntegerTy())
4382  Src = Builder.CreateBitCast(Src, DL.getIntPtrType(DstTy));
4383  // Cases 4a and 4b.
4384  return Builder.CreateIntToPtr(Src, DstTy, Name);
4385 }
4386 
4387 Value *ScalarExprEmitter::VisitAsTypeExpr(AsTypeExpr *E) {
4388  Value *Src = CGF.EmitScalarExpr(E->getSrcExpr());
4389  llvm::Type *DstTy = ConvertType(E->getType());
4390 
4391  llvm::Type *SrcTy = Src->getType();
4392  unsigned NumElementsSrc = isa<llvm::VectorType>(SrcTy) ?
4393  cast<llvm::VectorType>(SrcTy)->getNumElements() : 0;
4394  unsigned NumElementsDst = isa<llvm::VectorType>(DstTy) ?
4395  cast<llvm::VectorType>(DstTy)->getNumElements() : 0;
4396 
4397  // Going from vec3 to non-vec3 is a special case and requires a shuffle
4398  // vector to get a vec4, then a bitcast if the target type is different.
4399  if (NumElementsSrc == 3 && NumElementsDst != 3) {
4400  Src = ConvertVec3AndVec4(Builder, CGF, Src, 4);
4401 
4402  if (!CGF.CGM.getCodeGenOpts().PreserveVec3Type) {
4403  Src = createCastsForTypeOfSameSize(Builder, CGF.CGM.getDataLayout(), Src,
4404  DstTy);
4405  }
4406 
4407  Src->setName("astype");
4408  return Src;
4409  }
4410 
4411  // Going from non-vec3 to vec3 is a special case and requires a bitcast
4412  // to vec4 if the original type is not vec4, then a shuffle vector to
4413  // get a vec3.
4414  if (NumElementsSrc != 3 && NumElementsDst == 3) {
4415  if (!CGF.CGM.getCodeGenOpts().PreserveVec3Type) {
4416  auto Vec4Ty = llvm::VectorType::get(DstTy->getVectorElementType(), 4);
4417  Src = createCastsForTypeOfSameSize(Builder, CGF.CGM.getDataLayout(), Src,
4418  Vec4Ty);
4419  }
4420 
4421  Src = ConvertVec3AndVec4(Builder, CGF, Src, 3);
4422  Src->setName("astype");
4423  return Src;
4424  }
4425 
4426  return createCastsForTypeOfSameSize(Builder, CGF.CGM.getDataLayout(),
4427  Src, DstTy, "astype");
4428 }
4429 
4430 Value *ScalarExprEmitter::VisitAtomicExpr(AtomicExpr *E) {
4431  return CGF.EmitAtomicExpr(E).getScalarVal();
4432 }
4433 
4434 //===----------------------------------------------------------------------===//
4435 // Entry Point into this File
4436 //===----------------------------------------------------------------------===//
4437 
4438 /// Emit the computation of the specified expression of scalar type, ignoring
4439 /// the result.
4440 Value *CodeGenFunction::EmitScalarExpr(const Expr *E, bool IgnoreResultAssign) {
4441  assert(E && hasScalarEvaluationKind(E->getType()) &&
4442  "Invalid scalar expression to emit");
4443 
4444  return ScalarExprEmitter(*this, IgnoreResultAssign)
4445  .Visit(const_cast<Expr *>(E));
4446 }
4447 
4448 /// Emit a conversion from the specified type to the specified destination type,
4449 /// both of which are LLVM scalar types.
4451  QualType DstTy,
4452  SourceLocation Loc) {
4453  assert(hasScalarEvaluationKind(SrcTy) && hasScalarEvaluationKind(DstTy) &&
4454  "Invalid scalar expression to emit");
4455  return ScalarExprEmitter(*this).EmitScalarConversion(Src, SrcTy, DstTy, Loc);
4456 }
4457 
4458 /// Emit a conversion from the specified complex type to the specified
4459 /// destination type, where the destination type is an LLVM scalar type.
4461  QualType SrcTy,
4462  QualType DstTy,
4463  SourceLocation Loc) {
4464  assert(SrcTy->isAnyComplexType() && hasScalarEvaluationKind(DstTy) &&
4465  "Invalid complex -> scalar conversion");
4466  return ScalarExprEmitter(*this)
4467  .EmitComplexToScalarConversion(Src, SrcTy, DstTy, Loc);
4468 }
4469 
4470 
4473  bool isInc, bool isPre) {
4474  return ScalarExprEmitter(*this).EmitScalarPrePostIncDec(E, LV, isInc, isPre);
4475 }
4476 
4478  // object->isa or (*object).isa
4479  // Generate code as for: *(Class*)object
4480 
4481  Expr *BaseExpr = E->getBase();
4482  Address Addr = Address::invalid();
4483  if (BaseExpr->isRValue()) {
4484  Addr = Address(EmitScalarExpr(BaseExpr), getPointerAlign());
4485  } else {
4486  Addr = EmitLValue(BaseExpr).getAddress();
4487  }
4488 
4489  // Cast the address to Class*.
4490  Addr = Builder.CreateElementBitCast(Addr, ConvertType(E->getType()));
4491  return MakeAddrLValue(Addr, E->getType());
4492 }
4493 
4494 
4496  const CompoundAssignOperator *E) {
4497  ScalarExprEmitter Scalar(*this);
4498  Value *Result = nullptr;
4499  switch (E->getOpcode()) {
4500 #define COMPOUND_OP(Op) \
4501  case BO_##Op##Assign: \
4502  return Scalar.EmitCompoundAssignLValue(E, &ScalarExprEmitter::Emit##Op, \
4503  Result)
4504  COMPOUND_OP(Mul);
4505  COMPOUND_OP(Div);
4506  COMPOUND_OP(Rem);
4507  COMPOUND_OP(Add);
4508  COMPOUND_OP(Sub);
4509  COMPOUND_OP(Shl);
4510  COMPOUND_OP(Shr);
4511  COMPOUND_OP(And);
4512  COMPOUND_OP(Xor);
4513  COMPOUND_OP(Or);
4514 #undef COMPOUND_OP
4515 
4516  case BO_PtrMemD:
4517  case BO_PtrMemI:
4518  case BO_Mul:
4519  case BO_Div:
4520  case BO_Rem:
4521  case BO_Add:
4522  case BO_Sub:
4523  case BO_Shl:
4524  case BO_Shr:
4525  case BO_LT:
4526  case BO_GT:
4527  case BO_LE:
4528  case BO_GE:
4529  case BO_EQ:
4530  case BO_NE:
4531  case BO_Cmp:
4532  case BO_And:
4533  case BO_Xor:
4534  case BO_Or:
4535  case BO_LAnd:
4536  case BO_LOr:
4537  case BO_Assign:
4538  case BO_Comma:
4539  llvm_unreachable("Not valid compound assignment operators");
4540  }
4541 
4542  llvm_unreachable("Unhandled compound assignment operator");
4543 }
4544 
4546  // The total (signed) byte offset for the GEP.
4548  // The offset overflow flag - true if the total offset overflows.
4550 };
4551 
4552 /// Evaluate given GEPVal, which is either an inbounds GEP, or a constant,
4553 /// and compute the total offset it applies from it's base pointer BasePtr.
4554 /// Returns offset in bytes and a boolean flag whether an overflow happened
4555 /// during evaluation.
4557  llvm::LLVMContext &VMContext,
4558  CodeGenModule &CGM,
4559  CGBuilderTy Builder) {
4560  const auto &DL = CGM.getDataLayout();
4561 
4562  // The total (signed) byte offset for the GEP.
4563  llvm::Value *TotalOffset = nullptr;
4564 
4565  // Was the GEP already reduced to a constant?
4566  if (isa<llvm::Constant>(GEPVal)) {
4567  // Compute the offset by casting both pointers to integers and subtracting:
4568  // GEPVal = BasePtr + ptr(Offset) <--> Offset = int(GEPVal) - int(BasePtr)
4569  Value *BasePtr_int =
4570  Builder.CreatePtrToInt(BasePtr, DL.getIntPtrType(BasePtr->getType()));
4571  Value *GEPVal_int =
4572  Builder.CreatePtrToInt(GEPVal, DL.getIntPtrType(GEPVal->getType()));
4573  TotalOffset = Builder.CreateSub(GEPVal_int, BasePtr_int);
4574  return {TotalOffset, /*OffsetOverflows=*/Builder.getFalse()};
4575  }
4576 
4577  auto *GEP = cast<llvm::GEPOperator>(GEPVal);
4578  assert(GEP->getPointerOperand() == BasePtr &&
4579  "BasePtr must be the the base of the GEP.");
4580  assert(GEP->isInBounds() && "Expected inbounds GEP");
4581 
4582  auto *IntPtrTy = DL.getIntPtrType(GEP->getPointerOperandType());
4583 
4584  // Grab references to the signed add/mul overflow intrinsics for intptr_t.
4585  auto *Zero = llvm::ConstantInt::getNullValue(IntPtrTy);
4586  auto *SAddIntrinsic =
4587  CGM.getIntrinsic(llvm::Intrinsic::sadd_with_overflow, IntPtrTy);
4588  auto *SMulIntrinsic =
4589  CGM.getIntrinsic(llvm::Intrinsic::smul_with_overflow, IntPtrTy);
4590 
4591  // The offset overflow flag - true if the total offset overflows.
4592  llvm::Value *OffsetOverflows = Builder.getFalse();
4593 
4594  /// Return the result of the given binary operation.
4595  auto eval = [&](BinaryOperator::Opcode Opcode, llvm::Value *LHS,
4596  llvm::Value *RHS) -> llvm::Value * {
4597  assert((Opcode == BO_Add || Opcode == BO_Mul) && "Can't eval binop");
4598 
4599  // If the operands are constants, return a constant result.
4600  if (auto *LHSCI = dyn_cast<llvm::ConstantInt>(LHS)) {
4601  if (auto *RHSCI = dyn_cast<llvm::ConstantInt>(RHS)) {
4602  llvm::APInt N;
4603  bool HasOverflow = mayHaveIntegerOverflow(LHSCI, RHSCI, Opcode,
4604  /*Signed=*/true, N);
4605  if (HasOverflow)
4606  OffsetOverflows = Builder.getTrue();
4607  return llvm::ConstantInt::get(VMContext, N);
4608  }
4609  }
4610 
4611  // Otherwise, compute the result with checked arithmetic.
4612  auto *ResultAndOverflow = Builder.CreateCall(
4613  (Opcode == BO_Add) ? SAddIntrinsic : SMulIntrinsic, {LHS, RHS});
4614  OffsetOverflows = Builder.CreateOr(
4615  Builder.CreateExtractValue(ResultAndOverflow, 1), OffsetOverflows);
4616  return Builder.CreateExtractValue(ResultAndOverflow, 0);
4617  };
4618 
4619  // Determine the total byte offset by looking at each GEP operand.
4620  for (auto GTI = llvm::gep_type_begin(GEP), GTE = llvm::gep_type_end(GEP);
4621  GTI != GTE; ++GTI) {
4622  llvm::Value *LocalOffset;
4623  auto *Index = GTI.getOperand();
4624  // Compute the local offset contributed by this indexing step:
4625  if (auto *STy = GTI.getStructTypeOrNull()) {
4626  // For struct indexing, the local offset is the byte position of the
4627  // specified field.
4628  unsigned FieldNo = cast<llvm::ConstantInt>(Index)->getZExtValue();
4629  LocalOffset = llvm::ConstantInt::get(
4630  IntPtrTy, DL.getStructLayout(STy)->getElementOffset(FieldNo));
4631  } else {
4632  // Otherwise this is array-like indexing. The local offset is the index
4633  // multiplied by the element size.
4634  auto *ElementSize = llvm::ConstantInt::get(
4635  IntPtrTy, DL.getTypeAllocSize(GTI.getIndexedType()));
4636  auto *IndexS = Builder.CreateIntCast(Index, IntPtrTy, /*isSigned=*/true);
4637  LocalOffset = eval(BO_Mul, ElementSize, IndexS);
4638  }
4639 
4640  // If this is the first offset, set it as the total offset. Otherwise, add
4641  // the local offset into the running total.
4642  if (!TotalOffset || TotalOffset == Zero)
4643  TotalOffset = LocalOffset;
4644  else
4645  TotalOffset = eval(BO_Add, TotalOffset, LocalOffset);
4646  }
4647 
4648  return {TotalOffset, OffsetOverflows};
4649 }
4650 
4651 Value *
4653  bool SignedIndices, bool IsSubtraction,
4654  SourceLocation Loc, const Twine &Name) {
4655  Value *GEPVal = Builder.CreateInBoundsGEP(Ptr, IdxList, Name);
4656 
4657  // If the pointer overflow sanitizer isn't enabled, do nothing.
4658  if (!SanOpts.has(SanitizerKind::PointerOverflow))
4659  return GEPVal;
4660 
4661  llvm::Type *PtrTy = Ptr->getType();
4662 
4663  // Perform nullptr-and-offset check unless the nullptr is defined.
4664  bool PerformNullCheck = !NullPointerIsDefined(
4665  Builder.GetInsertBlock()->getParent(), PtrTy->getPointerAddressSpace());
4666  // Check for overflows unless the GEP got constant-folded,
4667  // and only in the default address space
4668  bool PerformOverflowCheck =
4669  !isa<llvm::Constant>(GEPVal) && PtrTy->getPointerAddressSpace() == 0;
4670 
4671  if (!(PerformNullCheck || PerformOverflowCheck))
4672  return GEPVal;
4673 
4674  const auto &DL = CGM.getDataLayout();
4675 
4676  SanitizerScope SanScope(this);
4677  llvm::Type *IntPtrTy = DL.getIntPtrType(PtrTy);
4678 
4679  GEPOffsetAndOverflow EvaluatedGEP =
4680  EmitGEPOffsetInBytes(Ptr, GEPVal, getLLVMContext(), CGM, Builder);
4681 
4682  assert((!isa<llvm::Constant>(EvaluatedGEP.TotalOffset) ||
4683  EvaluatedGEP.OffsetOverflows == Builder.getFalse()) &&
4684  "If the offset got constant-folded, we don't expect that there was an "
4685  "overflow.");
4686 
4687  auto *Zero = llvm::ConstantInt::getNullValue(IntPtrTy);
4688 
4689  // Common case: if the total offset is zero, and we are using C++ semantics,
4690  // where nullptr+0 is defined, don't emit a check.
4691  if (EvaluatedGEP.TotalOffset == Zero && CGM.getLangOpts().CPlusPlus)
4692  return GEPVal;
4693 
4694  // Now that we've computed the total offset, add it to the base pointer (with
4695  // wrapping semantics).
4696  auto *IntPtr = Builder.CreatePtrToInt(Ptr, IntPtrTy);
4697  auto *ComputedGEP = Builder.CreateAdd(IntPtr, EvaluatedGEP.TotalOffset);
4698 
4700 
4701  if (PerformNullCheck) {
4702  // In C++, if the base pointer evaluates to a null pointer value,
4703  // the only valid pointer this inbounds GEP can produce is also
4704  // a null pointer, so the offset must also evaluate to zero.
4705  // Likewise, if we have non-zero base pointer, we can not get null pointer
4706  // as a result, so the offset can not be -intptr_t(BasePtr).
4707  // In other words, both pointers are either null, or both are non-null,
4708  // or the behaviour is undefined.
4709  //
4710  // C, however, is more strict in this regard, and gives more
4711  // optimization opportunities: in C, additionally, nullptr+0 is undefined.
4712  // So both the input to the 'gep inbounds' AND the output must not be null.
4713  auto *BaseIsNotNullptr = Builder.CreateIsNotNull(Ptr);
4714  auto *ResultIsNotNullptr = Builder.CreateIsNotNull(ComputedGEP);
4715  auto *Valid =
4716  CGM.getLangOpts().CPlusPlus
4717  ? Builder.CreateICmpEQ(BaseIsNotNullptr, ResultIsNotNullptr)
4718  : Builder.CreateAnd(BaseIsNotNullptr, ResultIsNotNullptr);
4719  Checks.emplace_back(Valid, SanitizerKind::PointerOverflow);
4720  }
4721 
4722  if (PerformOverflowCheck) {
4723  // The GEP is valid if:
4724  // 1) The total offset doesn't overflow, and
4725  // 2) The sign of the difference between the computed address and the base
4726  // pointer matches the sign of the total offset.
4727  llvm::Value *ValidGEP;
4728  auto *NoOffsetOverflow = Builder.CreateNot(EvaluatedGEP.OffsetOverflows);
4729  if (SignedIndices) {
4730  // GEP is computed as `unsigned base + signed offset`, therefore:
4731  // * If offset was positive, then the computed pointer can not be
4732  // [unsigned] less than the base pointer, unless it overflowed.
4733  // * If offset was negative, then the computed pointer can not be
4734  // [unsigned] greater than the bas pointere, unless it overflowed.
4735  auto *PosOrZeroValid = Builder.CreateICmpUGE(ComputedGEP, IntPtr);
4736  auto *PosOrZeroOffset =
4737  Builder.CreateICmpSGE(EvaluatedGEP.TotalOffset, Zero);
4738  llvm::Value *NegValid = Builder.CreateICmpULT(ComputedGEP, IntPtr);
4739  ValidGEP =
4740  Builder.CreateSelect(PosOrZeroOffset, PosOrZeroValid, NegValid);
4741  } else if (!IsSubtraction) {
4742  // GEP is computed as `unsigned base + unsigned offset`, therefore the
4743  // computed pointer can not be [unsigned] less than base pointer,
4744  // unless there was an overflow.
4745  // Equivalent to `@llvm.uadd.with.overflow(%base, %offset)`.
4746  ValidGEP = Builder.CreateICmpUGE(ComputedGEP, IntPtr);
4747  } else {
4748  // GEP is computed as `unsigned base - unsigned offset`, therefore the
4749  // computed pointer can not be [unsigned] greater than base pointer,
4750  // unless there was an overflow.
4751  // Equivalent to `@llvm.usub.with.overflow(%base, sub(0, %offset))`.
4752  ValidGEP = Builder.CreateICmpULE(ComputedGEP, IntPtr);
4753  }
4754  ValidGEP = Builder.CreateAnd(ValidGEP, NoOffsetOverflow);
4755  Checks.emplace_back(ValidGEP, SanitizerKind::PointerOverflow);
4756  }
4757 
4758  assert(!Checks.empty() && "Should have produced some checks.");
4759 
4760  llvm::Constant *StaticArgs[] = {EmitCheckSourceLocation(Loc)};
4761  // Pass the computed GEP to the runtime to avoid emitting poisoned arguments.
4762  llvm::Value *DynamicArgs[] = {IntPtr, ComputedGEP};
4763  EmitCheck(Checks, SanitizerHandler::PointerOverflow, StaticArgs, DynamicArgs);
4764 
4765  return GEPVal;
4766 }
const llvm::DataLayout & getDataLayout() const
const Expr * getSubExpr() const
Definition: Expr.h:938
bool Mul(InterpState &S, CodePtr OpPC)
Definition: Interp.h:148
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:1980
The null pointer literal (C++11 [lex.nullptr])
Definition: ExprCXX.h:683
Expr * getChosenSubExpr() const
getChosenSubExpr - Return the subexpression chosen according to the condition.
Definition: Expr.h:4143
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:2670
bool isFixedPointType() const
Return true if this is a fixed point type according to ISO/IEC JTC1 SC22 WG14 N1169.
Definition: Type.h:6697
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:1253
bool isSignedOverflowDefined() const
Definition: LangOptions.h:288
PointerType - C99 6.7.5.1 - Pointer Declarators.
Definition: Type.h:2585
QualType getPointeeType() const
Definition: Type.h:2598
A (possibly-)qualified type.
Definition: Type.h:643
uint64_t getValue() const
Definition: ExprCXX.h:2760
bool sanitizePerformTypeCheck() const
Whether any type-checking sanitizers are enabled.
Definition: CGExpr.cpp:646
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:3546
const CodeGenOptions & getCodeGenOpts() const
SourceLocation getExprLoc() const
Definition: Expr.h:3440
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:1987
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:2791
void enterFullExpression(const FullExpr *E)
Expr * getExpr(unsigned Index)
getExpr - Return the Expr at the specified index.
Definition: Expr.h:4011
unsigned getNumSubExprs() const
getNumSubExprs - Return the size of the SubExprs array.
Definition: Expr.h:4005
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:2627
Expr * getResultExpr()
Return the result expression of this controlling expression.
Definition: Expr.h:5398
llvm::Constant * getMemberPointerConstant(const UnaryOperator *e)
CompoundStmt * getSubStmt()
Definition: Expr.h:3942
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:4423
static llvm::Constant * getAsInt32(llvm::ConstantInt *C, llvm::Type *I32Ty)
llvm::Value * OffsetOverflows
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:2466
QualType getPointeeType() const
If this is a pointer, ObjC object pointer, or block pointer, this returns the respective pointee...
Definition: Type.cpp:557
CharUnits getBaseClassOffset(const CXXRecordDecl *Base) const
getBaseClassOffset - Get the offset, in chars, for the given base class.
Definition: RecordLayout.h:232
bool isRealFloatingType() const
Floating point categories.
Definition: Type.cpp:2024
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:376
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:4603
Expr * getBase() const
Definition: Expr.h:2888
RValue EmitPseudoObjectRValue(const PseudoObjectExpr *e, AggValueSlot slot=AggValueSlot::ignored())
Definition: CGExpr.cpp:5087
llvm::APFloat getValue() const
Definition: Expr.h:1572
Represents the index of the current element of an array being initialized by an ArrayInitLoopExpr.
Definition: Expr.h:5054
bool isExtVectorType() const
Definition: Type.h:6487
bool isVirtual() const
Determines whether the base class is a virtual base class (or not).
Definition: DeclCXX.h:200
RValue EmitCoawaitExpr(const CoawaitExpr &E, AggValueSlot aggSlot=AggValueSlot::ignored(), bool ignoreResult=false)
Opcode getOpcode() const
Definition: Expr.h:3444
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:3005
ParenExpr - This represents a parethesized expression, e.g.
Definition: Expr.h:1969
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:6339
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:1927
FPOptions getFPFeatures() const
Definition: Expr.h:3586
An Embarcadero array type trait, as used in the implementation of __array_rank and __array_extent...
Definition: ExprCXX.h:2715
const TargetInfo & getTargetInfo() const
Definition: ASTContext.h:706
SourceLocation getLocation() const
Definition: Expr.h:4310
Floating point control options.
Definition: LangOptions.h:323
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:4419
bool isSatisfied() const
Whether or not the concept with the given arguments was satisfied when the expression was created...
Definition: ExprCXX.h:4935
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:2881
#define COMPOUND_OP(Op)
Expr * getIndexExpr(unsigned Idx)
Definition: Expr.h:2305
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:1971
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:3052
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:6858
uint64_t getProfileCount(const Stmt *S)
Get the profiler&#39;s count for the given statement.
const llvm::fltSemantics & getHalfFormat() const
Definition: TargetInfo.h:576
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:1140
Represents an expression – generally a full-expression – that introduces cleanups to be run at the ...
Definition: ExprCXX.h:3306
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:2024
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:3662
const TargetInfo & getTarget() const
An object to manage conditionally-evaluated expressions.
Expr * getSemanticForm()
Get an equivalent semantic form for this expression.
Definition: ExprCXX.h:293
llvm::Value * EmitCXXNewExpr(const CXXNewExpr *E)
Definition: CGExprCXX.cpp:1534
FieldDecl * getField() const
For a field offsetof node, returns the field.
Definition: Expr.h:2202
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:4267
ShuffleVectorExpr - clang-specific builtin-in function __builtin_shufflevector.
Definition: Expr.h:3971
Address getAddress() const
Definition: CGValue.h:326
QualType getComputationResultType() const
Definition: Expr.h:3655
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:160
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:2182
SourceLocation getBeginLoc() const LLVM_READONLY
Definition: Stmt.cpp:274
bool isVolatileQualified() const
Definition: CGValue.h:257
Represents a member of a struct/union/class.
Definition: Decl.h:2643
An RAII object to set (and then clear) a mapping for an OpaqueValueExpr.
bool Zero(InterpState &S, CodePtr OpPC)
Definition: Interp.h:815
unsigned getArrayExprIndex() const
For an array element node, returns the index into the array of expressions.
Definition: Expr.h:2196
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:4182
bool isReferenceType() const
Definition: Type.h:6403
__DEVICE__ int max(int __a, int __b)
Expr * getSubExpr()
Definition: Expr.h:3177
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:4545
bool GE(InterpState &S, CodePtr OpPC)
Definition: Interp.h:255
An r-value expression (a pr-value in the C++11 taxonomy) produces a temporary value.
Definition: Specifiers.h:125
static ApplyDebugLocation CreateArtificial(CodeGenFunction &CGF)
Apply TemporaryLocation if it is valid.
Definition: CGDebugInfo.h:742
bool isGLValue() const
Definition: Expr.h:261
Describes an C or C++ initializer list.
Definition: Expr.h:4375
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:38
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:119
path_iterator path_begin()
Definition: Expr.h:3197
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:3409
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:6148
unsigned getScale() const
Definition: FixedPoint.h:45
field_iterator field_begin() const
Definition: Decl.cpp:4343
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:182
CastExpr - Base class for type casts, including both implicit casts (ImplicitCastExpr) and explicit c...
Definition: Expr.h:3125
Helper class for OffsetOfExpr.
Definition: Expr.h:2138
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:746
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
static GEPOffsetAndOverflow EmitGEPOffsetInBytes(Value *BasePtr, Value *GEPVal, llvm::LLVMContext &VMContext, CodeGenModule &CGM, CGBuilderTy Builder)
Evaluate given GEPVal, which is either an inbounds GEP, or a constant, and compute the total offset i...
A default argument (C++ [dcl.fct.default]).
Definition: ExprCXX.h:1202
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:2950
This object can be modified without requiring retains or releases.
Definition: Type.h:158
Represents the this expression in C++.
Definition: ExprCXX.h:1097
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:2102
const Expr * getExpr() const
Get the initialization expression that will be used.
Definition: ExprCXX.h:1307
#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:6656
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:331
bool isPromotableIntegerType() const
More type predicates useful for type checking/promotion.
Definition: Type.cpp:2563
static CharUnits One()
One - Construct a CharUnits quantity of one.
Definition: CharUnits.h:58
Represents a C++ pseudo-destructor (C++ [expr.pseudo]).
Definition: ExprCXX.h:2479
std::pair< llvm::Value *, llvm::Value * > ComplexPairTy
const TargetCodeGenInfo & getTargetCodeGenInfo()
QualType getComputationLHSType() const
Definition: Expr.h:3652
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:2347
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:179
ConstantExpr - An expression that occurs in a constant context and optionally the result of evaluatin...
Definition: Expr.h:953
Represents a call to the builtin function __builtin_va_arg.
Definition: Expr.h:4216
llvm::APSInt EvaluateKnownConstInt(const ASTContext &Ctx, SmallVectorImpl< PartialDiagnosticAt > *Diag=nullptr) const
EvaluateKnownConstInt - Call EvaluateAsRValue and return the folded integer.
unsigned Offset
Definition: Format.cpp:1809
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:592
unsigned getValue() const
Definition: Expr.h:1539
llvm::Value * emitScalarConstant(const ConstantEmission &Constant, Expr *E)
Definition: CGExpr.cpp:1514
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:5623
llvm::APSInt getShuffleMaskIdx(const ASTContext &Ctx, unsigned N) const
Definition: Expr.h:4022
An expression "T()" which creates a value-initialized rvalue of type T, which is a non-class type...
Definition: ExprCXX.h:2053
bool isEventT() const
Definition: Type.h:6560
Represent the declaration of a variable (in which case it is an lvalue) a function (in which case it ...
Definition: Decl.h:644
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:2212
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:1677
unsigned getPackLength() const
Retrieve the length of the parameter pack.
Definition: ExprCXX.h:4168
const T * castAs() const
Member-template castAs<specific type>.
Definition: Type.h:6923
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:2921
BlockExpr - Adaptor class for mixing a BlockDecl with expressions.
Definition: Expr.h:5551
Address EmitCompoundStmt(const CompoundStmt &S, bool GetLast=false, AggValueSlot AVS=AggValueSlot::ignored())
EmitCompoundStmt - Emit a compound statement {..} node.
Definition: CGStmt.cpp:379
unsigned getNumInits() const
Definition: Expr.h:4405
bool isNullPtrType() const
Definition: Type.h:6675
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:4997
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:3880
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:1691
bool isAnyComplexType() const
Definition: Type.h:6479
ObjCSelectorExpr used for @selector in Objective-C.
Definition: ExprObjC.h:454
TypeSourceInfo * getTypeSourceInfo() const
Definition: Expr.h:2284
Represents an expression that computes the length of a parameter pack.
Definition: ExprCXX.h:4091
AsTypeExpr - Clang builtin function __builtin_astype [OpenCL 6.2.4.2] This AST node provides support ...
Definition: Expr.h:5600
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:2192
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:719
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:2410
bool Shl(InterpState &S, CodePtr OpPC)
Definition: Interp.h:914
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:653
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:2021
Represents a GCC generic vector type.
Definition: Type.h:3206
bool isNullPointer() const
Definition: APValue.cpp:769
llvm::Value * EmitCastToVoidPtr(llvm::Value *value)
Emit a cast to void* in the appropriate address space.
Definition: CGExpr.cpp:50
ConstantEmission tryEmitAsConstant(DeclRefExpr *refExpr)
Try to emit a reference to the given value without producing it as an l-value.
Definition: CGExpr.cpp:1433
Represents a reference to a non-type template parameter that has been substituted with a template arg...
Definition: ExprCXX.h:4209
const OffsetOfNode & getComponent(unsigned Idx) const
Definition: Expr.h:2291
const TargetInfo & getTarget() const
const Expr * getSubExpr() const
Definition: Expr.h:1985
bool getValue() const
Definition: ExprCXX.h:657
The l-value was considered opaque, so the alignment was determined from a type.
RecordDecl * getDecl() const
Definition: Type.h:4454
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:753
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:3984
A C++ dynamic_cast expression (C++ [expr.dynamic.cast]).
Definition: ExprCXX.h:445
OpaqueValueExpr - An expression referring to an opaque object of a fixed type and value class...
Definition: Expr.h:1050
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:4039
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:2147
PseudoObjectExpr - An expression which accesses a pseudo-object l-value.
Definition: Expr.h:5673
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
llvm::APSInt APSInt
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:97
LangAS getAddressSpace() const
Return the address space of this type.
Definition: Type.h:6264
bool allowFPContractAcrossStatement() const
Definition: LangOptions.h:343
unsigned getOpenMPDefaultSimdAlign(QualType T) const
Get default simd alignment of the specified complete type in bits.
Expr * getSubExpr() const
Definition: Expr.h:2051
llvm::Value * EvaluateExprAsBool(const Expr *E)
EvaluateExprAsBool - Perform the usual unary conversions on the specified expression and compare the ...
Definition: CGExpr.cpp:164
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:2137
llvm::Value * EmitFromMemory(llvm::Value *Value, QualType Ty)
EmitFromMemory - Change a scalar value from its memory representation to its value representation...
Definition: CGExpr.cpp:1705
CastKind getCastKind() const
Definition: Expr.h:3171
Represents a new-expression for memory allocation and constructor calls, e.g: "new CXXNewExpr(foo)"...
Definition: ExprCXX.h:2100
QualType getElementType() const
Definition: Type.h:3241
A scoped helper to set the current debug location to the specified location or preferred location of ...
Definition: CGDebugInfo.h:711
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:2064
CanQualType FloatTy
Definition: ASTContext.h:1027
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:1947
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:5807
UnaryExprOrTypeTrait getKind() const
Definition: Expr.h:2378
APValue EvaluateInContext(const ASTContext &Ctx, const Expr *DefaultExpr) const