1 //===--- CGExprScalar.cpp - Emit LLVM Code for Scalar Exprs ---------------===//
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
7 //===----------------------------------------------------------------------===//
9 // This contains code to emit Expr nodes with scalar LLVM types as LLVM code.
11 //===----------------------------------------------------------------------===//
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"
26 #include "clang/Basic/CodeGenOptions.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"
40 using namespace clang;
41 using namespace CodeGen;
44 //===----------------------------------------------------------------------===//
45 // Scalar Expression Emitter
46 //===----------------------------------------------------------------------===//
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.
60 const auto &LHSAP = LHS->getValue();
61 const auto &RHSAP = RHS->getValue();
62 if (Opcode == BO_Add) {
64 Result = LHSAP.sadd_ov(RHSAP, Overflow);
66 Result = LHSAP.uadd_ov(RHSAP, Overflow);
67 } else if (Opcode == BO_Sub) {
69 Result = LHSAP.ssub_ov(RHSAP, Overflow);
71 Result = LHSAP.usub_ov(RHSAP, Overflow);
72 } else if (Opcode == BO_Mul) {
74 Result = LHSAP.smul_ov(RHSAP, Overflow);
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);
89 QualType Ty; // Computation Type.
90 BinaryOperator::Opcode Opcode; // Opcode of BinOp to perform
92 const Expr *E; // Entire expr, for error unsupported. May not be binop.
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);
103 return ::mayHaveIntegerOverflow(
104 LHSCI, RHSCI, Opcode, Ty->hasSignedIntegerRepresentation(), Result);
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;
113 /// Check if the binop can result in an integer division by zero.
114 bool mayHaveIntegerDivisionByZero() const {
116 if (auto *CI = dyn_cast<llvm::ConstantInt>(RHS))
121 /// Check if the binop can result in a float division by zero.
122 bool mayHaveFloatDivisionByZero() const {
124 if (auto *CFP = dyn_cast<llvm::ConstantFP>(RHS))
125 return CFP->isZero();
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
133 bool isFixedPointBinOp() const {
134 // We cannot simply check the result type since comparison operations return
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();
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();
152 /// If \p E is a widened promoted integer, get its base (unpromoted) type.
153 static llvm::Optional<QualType> getUnwidenedIntegerType(const ASTContext &Ctx,
155 const Expr *Base = E->IgnoreImpCasts();
159 QualType BaseTy = Base->getType();
160 if (!BaseTy->isPromotableIntegerType() ||
161 Ctx.getTypeSize(BaseTy) >= Ctx.getTypeSize(E->getType()))
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();
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");
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())
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();
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());
193 auto OptionalRHSTy = getUnwidenedIntegerType(Ctx, BO->getRHS());
197 QualType LHSTy = *OptionalLHSTy;
198 QualType RHSTy = *OptionalRHSTy;
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())
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;
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());
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);
229 class ScalarExprEmitter
230 : public StmtVisitor<ScalarExprEmitter, Value*> {
231 CodeGenFunction &CGF;
232 CGBuilderTy &Builder;
233 bool IgnoreResultAssign;
234 llvm::LLVMContext &VMContext;
237 ScalarExprEmitter(CodeGenFunction &cgf, bool ira=false)
238 : CGF(cgf), Builder(CGF.Builder), IgnoreResultAssign(ira),
239 VMContext(cgf.getLLVMContext()) {
242 //===--------------------------------------------------------------------===//
244 //===--------------------------------------------------------------------===//
246 bool TestAndClearIgnoreResultAssign() {
247 bool I = IgnoreResultAssign;
248 IgnoreResultAssign = false;
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);
258 void EmitBinOpCheck(ArrayRef<std::pair<Value *, SanitizerMask>> Checks,
259 const BinOpInfo &Info);
261 Value *EmitLoadOfLValue(LValue LV, SourceLocation Loc) {
262 return CGF.EmitLoadOfLValue(LV, Loc).getScalarVal();
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();
270 if (VD->getType()->isReferenceType()) {
271 if (const auto *TTy =
272 dyn_cast<TypedefType>(VD->getType().getNonReferenceType()))
273 AVAttr = TTy->getDecl()->getAttr<AlignValueAttr>();
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))
283 AVAttr = VD->getAttr<AlignValueAttr>();
288 if (const auto *TTy =
289 dyn_cast<TypedefType>(E->getType()))
290 AVAttr = TTy->getDecl()->getAttr<AlignValueAttr>();
295 Value *AlignmentValue = CGF.EmitScalarExpr(AVAttr->getAlignment());
296 llvm::ConstantInt *AlignmentCI = cast<llvm::ConstantInt>(AlignmentValue);
297 CGF.EmitAlignmentAssumption(V, E, AVAttr->getLocation(),
298 AlignmentCI->getZExtValue());
301 /// EmitLoadOfLValue - Given an expression with complex type that represents a
302 /// value l-value, this method emits the address of the l-value, then loads
303 /// and returns the result.
304 Value *EmitLoadOfLValue(const Expr *E) {
305 Value *V = EmitLoadOfLValue(EmitCheckedLValue(E, CodeGenFunction::TCK_Load),
308 EmitLValueAlignmentAssumption(E, V);
312 /// EmitConversionToBool - Convert the specified expression value to a
313 /// boolean (i1) truth value. This is equivalent to "Val != 0".
314 Value *EmitConversionToBool(Value *Src, QualType DstTy);
316 /// Emit a check that a conversion from a floating-point type does not
318 void EmitFloatConversionCheck(Value *OrigSrc, QualType OrigSrcType,
319 Value *Src, QualType SrcType, QualType DstType,
320 llvm::Type *DstTy, SourceLocation Loc);
322 /// Known implicit conversion check kinds.
323 /// Keep in sync with the enum of the same name in ubsan_handlers.h
324 enum ImplicitConversionCheckKind : unsigned char {
325 ICCK_IntegerTruncation = 0, // Legacy, was only used by clang 7.
326 ICCK_UnsignedIntegerTruncation = 1,
327 ICCK_SignedIntegerTruncation = 2,
328 ICCK_IntegerSignChange = 3,
329 ICCK_SignedIntegerTruncationOrSignChange = 4,
332 /// Emit a check that an [implicit] truncation of an integer does not
333 /// discard any bits. It is not UB, so we use the value after truncation.
334 void EmitIntegerTruncationCheck(Value *Src, QualType SrcType, Value *Dst,
335 QualType DstType, SourceLocation Loc);
337 /// Emit a check that an [implicit] conversion of an integer does not change
338 /// the sign of the value. It is not UB, so we use the value after conversion.
339 /// NOTE: Src and Dst may be the exact same value! (point to the same thing)
340 void EmitIntegerSignChangeCheck(Value *Src, QualType SrcType, Value *Dst,
341 QualType DstType, SourceLocation Loc);
343 /// Emit a conversion from the specified type to the specified destination
344 /// type, both of which are LLVM scalar types.
345 struct ScalarConversionOpts {
346 bool TreatBooleanAsSigned;
347 bool EmitImplicitIntegerTruncationChecks;
348 bool EmitImplicitIntegerSignChangeChecks;
350 ScalarConversionOpts()
351 : TreatBooleanAsSigned(false),
352 EmitImplicitIntegerTruncationChecks(false),
353 EmitImplicitIntegerSignChangeChecks(false) {}
355 ScalarConversionOpts(clang::SanitizerSet SanOpts)
356 : TreatBooleanAsSigned(false),
357 EmitImplicitIntegerTruncationChecks(
358 SanOpts.hasOneOf(SanitizerKind::ImplicitIntegerTruncation)),
359 EmitImplicitIntegerSignChangeChecks(
360 SanOpts.has(SanitizerKind::ImplicitIntegerSignChange)) {}
363 EmitScalarConversion(Value *Src, QualType SrcTy, QualType DstTy,
365 ScalarConversionOpts Opts = ScalarConversionOpts());
367 /// Convert between either a fixed point and other fixed point or fixed point
369 Value *EmitFixedPointConversion(Value *Src, QualType SrcTy, QualType DstTy,
371 Value *EmitFixedPointConversion(Value *Src, FixedPointSemantics &SrcFixedSema,
372 FixedPointSemantics &DstFixedSema,
374 bool DstIsInteger = false);
376 /// Emit a conversion from the specified complex type to the specified
377 /// destination type, where the destination type is an LLVM scalar type.
378 Value *EmitComplexToScalarConversion(CodeGenFunction::ComplexPairTy Src,
379 QualType SrcTy, QualType DstTy,
382 /// EmitNullValue - Emit a value that corresponds to null for the given type.
383 Value *EmitNullValue(QualType Ty);
385 /// EmitFloatToBoolConversion - Perform an FP to boolean conversion.
386 Value *EmitFloatToBoolConversion(Value *V) {
387 // Compare against 0.0 for fp scalars.
388 llvm::Value *Zero = llvm::Constant::getNullValue(V->getType());
389 return Builder.CreateFCmpUNE(V, Zero, "tobool");
392 /// EmitPointerToBoolConversion - Perform a pointer to boolean conversion.
393 Value *EmitPointerToBoolConversion(Value *V, QualType QT) {
394 Value *Zero = CGF.CGM.getNullPointer(cast<llvm::PointerType>(V->getType()), QT);
396 return Builder.CreateICmpNE(V, Zero, "tobool");
399 Value *EmitIntToBoolConversion(Value *V) {
400 // Because of the type rules of C, we often end up computing a
401 // logical value, then zero extending it to int, then wanting it
402 // as a logical value again. Optimize this common case.
403 if (llvm::ZExtInst *ZI = dyn_cast<llvm::ZExtInst>(V)) {
404 if (ZI->getOperand(0)->getType() == Builder.getInt1Ty()) {
405 Value *Result = ZI->getOperand(0);
406 // If there aren't any more uses, zap the instruction to save space.
407 // Note that there can be more uses, for example if this
408 // is the result of an assignment.
410 ZI->eraseFromParent();
415 return Builder.CreateIsNotNull(V, "tobool");
418 //===--------------------------------------------------------------------===//
420 //===--------------------------------------------------------------------===//
422 Value *Visit(Expr *E) {
423 ApplyDebugLocation DL(CGF, E);
424 return StmtVisitor<ScalarExprEmitter, Value*>::Visit(E);
427 Value *VisitStmt(Stmt *S) {
428 S->dump(CGF.getContext().getSourceManager());
429 llvm_unreachable("Stmt can't have complex result type!");
431 Value *VisitExpr(Expr *S);
433 Value *VisitConstantExpr(ConstantExpr *E) {
434 return Visit(E->getSubExpr());
436 Value *VisitParenExpr(ParenExpr *PE) {
437 return Visit(PE->getSubExpr());
439 Value *VisitSubstNonTypeTemplateParmExpr(SubstNonTypeTemplateParmExpr *E) {
440 return Visit(E->getReplacement());
442 Value *VisitGenericSelectionExpr(GenericSelectionExpr *GE) {
443 return Visit(GE->getResultExpr());
445 Value *VisitCoawaitExpr(CoawaitExpr *S) {
446 return CGF.EmitCoawaitExpr(*S).getScalarVal();
448 Value *VisitCoyieldExpr(CoyieldExpr *S) {
449 return CGF.EmitCoyieldExpr(*S).getScalarVal();
451 Value *VisitUnaryCoawait(const UnaryOperator *E) {
452 return Visit(E->getSubExpr());
456 Value *VisitIntegerLiteral(const IntegerLiteral *E) {
457 return Builder.getInt(E->getValue());
459 Value *VisitFixedPointLiteral(const FixedPointLiteral *E) {
460 return Builder.getInt(E->getValue());
462 Value *VisitFloatingLiteral(const FloatingLiteral *E) {
463 return llvm::ConstantFP::get(VMContext, E->getValue());
465 Value *VisitCharacterLiteral(const CharacterLiteral *E) {
466 return llvm::ConstantInt::get(ConvertType(E->getType()), E->getValue());
468 Value *VisitObjCBoolLiteralExpr(const ObjCBoolLiteralExpr *E) {
469 return llvm::ConstantInt::get(ConvertType(E->getType()), E->getValue());
471 Value *VisitCXXBoolLiteralExpr(const CXXBoolLiteralExpr *E) {
472 return llvm::ConstantInt::get(ConvertType(E->getType()), E->getValue());
474 Value *VisitCXXScalarValueInitExpr(const CXXScalarValueInitExpr *E) {
475 return EmitNullValue(E->getType());
477 Value *VisitGNUNullExpr(const GNUNullExpr *E) {
478 return EmitNullValue(E->getType());
480 Value *VisitOffsetOfExpr(OffsetOfExpr *E);
481 Value *VisitUnaryExprOrTypeTraitExpr(const UnaryExprOrTypeTraitExpr *E);
482 Value *VisitAddrLabelExpr(const AddrLabelExpr *E) {
483 llvm::Value *V = CGF.GetAddrOfLabel(E->getLabel());
484 return Builder.CreateBitCast(V, ConvertType(E->getType()));
487 Value *VisitSizeOfPackExpr(SizeOfPackExpr *E) {
488 return llvm::ConstantInt::get(ConvertType(E->getType()),E->getPackLength());
491 Value *VisitPseudoObjectExpr(PseudoObjectExpr *E) {
492 return CGF.EmitPseudoObjectRValue(E).getScalarVal();
495 Value *VisitOpaqueValueExpr(OpaqueValueExpr *E) {
497 return EmitLoadOfLValue(CGF.getOrCreateOpaqueLValueMapping(E),
500 // Otherwise, assume the mapping is the scalar directly.
501 return CGF.getOrCreateOpaqueRValueMapping(E).getScalarVal();
505 Value *VisitDeclRefExpr(DeclRefExpr *E) {
506 if (CodeGenFunction::ConstantEmission Constant = CGF.tryEmitAsConstant(E))
507 return CGF.emitScalarConstant(Constant, E);
508 return EmitLoadOfLValue(E);
511 Value *VisitObjCSelectorExpr(ObjCSelectorExpr *E) {
512 return CGF.EmitObjCSelectorExpr(E);
514 Value *VisitObjCProtocolExpr(ObjCProtocolExpr *E) {
515 return CGF.EmitObjCProtocolExpr(E);
517 Value *VisitObjCIvarRefExpr(ObjCIvarRefExpr *E) {
518 return EmitLoadOfLValue(E);
520 Value *VisitObjCMessageExpr(ObjCMessageExpr *E) {
521 if (E->getMethodDecl() &&
522 E->getMethodDecl()->getReturnType()->isReferenceType())
523 return EmitLoadOfLValue(E);
524 return CGF.EmitObjCMessageExpr(E).getScalarVal();
527 Value *VisitObjCIsaExpr(ObjCIsaExpr *E) {
528 LValue LV = CGF.EmitObjCIsaExpr(E);
529 Value *V = CGF.EmitLoadOfLValue(LV, E->getExprLoc()).getScalarVal();
533 Value *VisitObjCAvailabilityCheckExpr(ObjCAvailabilityCheckExpr *E) {
534 VersionTuple Version = E->getVersion();
536 // If we're checking for a platform older than our minimum deployment
537 // target, we can fold the check away.
538 if (Version <= CGF.CGM.getTarget().getPlatformMinVersion())
539 return llvm::ConstantInt::get(Builder.getInt1Ty(), 1);
541 Optional<unsigned> Min = Version.getMinor(), SMin = Version.getSubminor();
542 llvm::Value *Args[] = {
543 llvm::ConstantInt::get(CGF.CGM.Int32Ty, Version.getMajor()),
544 llvm::ConstantInt::get(CGF.CGM.Int32Ty, Min ? *Min : 0),
545 llvm::ConstantInt::get(CGF.CGM.Int32Ty, SMin ? *SMin : 0),
548 return CGF.EmitBuiltinAvailable(Args);
551 Value *VisitArraySubscriptExpr(ArraySubscriptExpr *E);
552 Value *VisitShuffleVectorExpr(ShuffleVectorExpr *E);
553 Value *VisitConvertVectorExpr(ConvertVectorExpr *E);
554 Value *VisitMemberExpr(MemberExpr *E);
555 Value *VisitExtVectorElementExpr(Expr *E) { return EmitLoadOfLValue(E); }
556 Value *VisitCompoundLiteralExpr(CompoundLiteralExpr *E) {
557 return EmitLoadOfLValue(E);
560 Value *VisitInitListExpr(InitListExpr *E);
562 Value *VisitArrayInitIndexExpr(ArrayInitIndexExpr *E) {
563 assert(CGF.getArrayInitIndex() &&
564 "ArrayInitIndexExpr not inside an ArrayInitLoopExpr?");
565 return CGF.getArrayInitIndex();
568 Value *VisitImplicitValueInitExpr(const ImplicitValueInitExpr *E) {
569 return EmitNullValue(E->getType());
571 Value *VisitExplicitCastExpr(ExplicitCastExpr *E) {
572 CGF.CGM.EmitExplicitCastExprType(E, &CGF);
573 return VisitCastExpr(E);
575 Value *VisitCastExpr(CastExpr *E);
577 Value *VisitCallExpr(const CallExpr *E) {
578 if (E->getCallReturnType(CGF.getContext())->isReferenceType())
579 return EmitLoadOfLValue(E);
581 Value *V = CGF.EmitCallExpr(E).getScalarVal();
583 EmitLValueAlignmentAssumption(E, V);
587 Value *VisitStmtExpr(const StmtExpr *E);
590 Value *VisitUnaryPostDec(const UnaryOperator *E) {
591 LValue LV = EmitLValue(E->getSubExpr());
592 return EmitScalarPrePostIncDec(E, LV, false, false);
594 Value *VisitUnaryPostInc(const UnaryOperator *E) {
595 LValue LV = EmitLValue(E->getSubExpr());
596 return EmitScalarPrePostIncDec(E, LV, true, false);
598 Value *VisitUnaryPreDec(const UnaryOperator *E) {
599 LValue LV = EmitLValue(E->getSubExpr());
600 return EmitScalarPrePostIncDec(E, LV, false, true);
602 Value *VisitUnaryPreInc(const UnaryOperator *E) {
603 LValue LV = EmitLValue(E->getSubExpr());
604 return EmitScalarPrePostIncDec(E, LV, true, true);
607 llvm::Value *EmitIncDecConsiderOverflowBehavior(const UnaryOperator *E,
611 llvm::Value *EmitScalarPrePostIncDec(const UnaryOperator *E, LValue LV,
612 bool isInc, bool isPre);
615 Value *VisitUnaryAddrOf(const UnaryOperator *E) {
616 if (isa<MemberPointerType>(E->getType())) // never sugared
617 return CGF.CGM.getMemberPointerConstant(E);
619 return EmitLValue(E->getSubExpr()).getPointer();
621 Value *VisitUnaryDeref(const UnaryOperator *E) {
622 if (E->getType()->isVoidType())
623 return Visit(E->getSubExpr()); // the actual value should be unused
624 return EmitLoadOfLValue(E);
626 Value *VisitUnaryPlus(const UnaryOperator *E) {
627 // This differs from gcc, though, most likely due to a bug in gcc.
628 TestAndClearIgnoreResultAssign();
629 return Visit(E->getSubExpr());
631 Value *VisitUnaryMinus (const UnaryOperator *E);
632 Value *VisitUnaryNot (const UnaryOperator *E);
633 Value *VisitUnaryLNot (const UnaryOperator *E);
634 Value *VisitUnaryReal (const UnaryOperator *E);
635 Value *VisitUnaryImag (const UnaryOperator *E);
636 Value *VisitUnaryExtension(const UnaryOperator *E) {
637 return Visit(E->getSubExpr());
641 Value *VisitMaterializeTemporaryExpr(const MaterializeTemporaryExpr *E) {
642 return EmitLoadOfLValue(E);
644 Value *VisitSourceLocExpr(SourceLocExpr *SLE) {
645 auto &Ctx = CGF.getContext();
647 SLE->EvaluateInContext(Ctx, CGF.CurSourceLocExprScope.getDefaultExpr());
648 return ConstantEmitter(CGF.CGM, &CGF)
649 .emitAbstract(SLE->getLocation(), Evaluated, SLE->getType());
652 Value *VisitCXXDefaultArgExpr(CXXDefaultArgExpr *DAE) {
653 CodeGenFunction::CXXDefaultArgExprScope Scope(CGF, DAE);
654 return Visit(DAE->getExpr());
656 Value *VisitCXXDefaultInitExpr(CXXDefaultInitExpr *DIE) {
657 CodeGenFunction::CXXDefaultInitExprScope Scope(CGF, DIE);
658 return Visit(DIE->getExpr());
660 Value *VisitCXXThisExpr(CXXThisExpr *TE) {
661 return CGF.LoadCXXThis();
664 Value *VisitExprWithCleanups(ExprWithCleanups *E);
665 Value *VisitCXXNewExpr(const CXXNewExpr *E) {
666 return CGF.EmitCXXNewExpr(E);
668 Value *VisitCXXDeleteExpr(const CXXDeleteExpr *E) {
669 CGF.EmitCXXDeleteExpr(E);
673 Value *VisitTypeTraitExpr(const TypeTraitExpr *E) {
674 return llvm::ConstantInt::get(ConvertType(E->getType()), E->getValue());
677 Value *VisitArrayTypeTraitExpr(const ArrayTypeTraitExpr *E) {
678 return llvm::ConstantInt::get(Builder.getInt32Ty(), E->getValue());
681 Value *VisitExpressionTraitExpr(const ExpressionTraitExpr *E) {
682 return llvm::ConstantInt::get(Builder.getInt1Ty(), E->getValue());
685 Value *VisitCXXPseudoDestructorExpr(const CXXPseudoDestructorExpr *E) {
686 // C++ [expr.pseudo]p1:
687 // The result shall only be used as the operand for the function call
688 // operator (), and the result of such a call has type void. The only
689 // effect is the evaluation of the postfix-expression before the dot or
691 CGF.EmitScalarExpr(E->getBase());
695 Value *VisitCXXNullPtrLiteralExpr(const CXXNullPtrLiteralExpr *E) {
696 return EmitNullValue(E->getType());
699 Value *VisitCXXThrowExpr(const CXXThrowExpr *E) {
700 CGF.EmitCXXThrowExpr(E);
704 Value *VisitCXXNoexceptExpr(const CXXNoexceptExpr *E) {
705 return Builder.getInt1(E->getValue());
709 Value *EmitMul(const BinOpInfo &Ops) {
710 if (Ops.Ty->isSignedIntegerOrEnumerationType()) {
711 switch (CGF.getLangOpts().getSignedOverflowBehavior()) {
712 case LangOptions::SOB_Defined:
713 return Builder.CreateMul(Ops.LHS, Ops.RHS, "mul");
714 case LangOptions::SOB_Undefined:
715 if (!CGF.SanOpts.has(SanitizerKind::SignedIntegerOverflow))
716 return Builder.CreateNSWMul(Ops.LHS, Ops.RHS, "mul");
718 case LangOptions::SOB_Trapping:
719 if (CanElideOverflowCheck(CGF.getContext(), Ops))
720 return Builder.CreateNSWMul(Ops.LHS, Ops.RHS, "mul");
721 return EmitOverflowCheckedBinOp(Ops);
725 if (Ops.Ty->isUnsignedIntegerType() &&
726 CGF.SanOpts.has(SanitizerKind::UnsignedIntegerOverflow) &&
727 !CanElideOverflowCheck(CGF.getContext(), Ops))
728 return EmitOverflowCheckedBinOp(Ops);
730 if (Ops.LHS->getType()->isFPOrFPVectorTy()) {
731 Value *V = Builder.CreateFMul(Ops.LHS, Ops.RHS, "mul");
732 return propagateFMFlags(V, Ops);
734 return Builder.CreateMul(Ops.LHS, Ops.RHS, "mul");
736 /// Create a binary op that checks for overflow.
737 /// Currently only supports +, - and *.
738 Value *EmitOverflowCheckedBinOp(const BinOpInfo &Ops);
740 // Check for undefined division and modulus behaviors.
741 void EmitUndefinedBehaviorIntegerDivAndRemCheck(const BinOpInfo &Ops,
742 llvm::Value *Zero,bool isDiv);
743 // Common helper for getting how wide LHS of shift is.
744 static Value *GetWidthMinusOneValue(Value* LHS,Value* RHS);
745 Value *EmitDiv(const BinOpInfo &Ops);
746 Value *EmitRem(const BinOpInfo &Ops);
747 Value *EmitAdd(const BinOpInfo &Ops);
748 Value *EmitSub(const BinOpInfo &Ops);
749 Value *EmitShl(const BinOpInfo &Ops);
750 Value *EmitShr(const BinOpInfo &Ops);
751 Value *EmitAnd(const BinOpInfo &Ops) {
752 return Builder.CreateAnd(Ops.LHS, Ops.RHS, "and");
754 Value *EmitXor(const BinOpInfo &Ops) {
755 return Builder.CreateXor(Ops.LHS, Ops.RHS, "xor");
757 Value *EmitOr (const BinOpInfo &Ops) {
758 return Builder.CreateOr(Ops.LHS, Ops.RHS, "or");
761 // Helper functions for fixed point binary operations.
762 Value *EmitFixedPointBinOp(const BinOpInfo &Ops);
764 BinOpInfo EmitBinOps(const BinaryOperator *E);
765 LValue EmitCompoundAssignLValue(const CompoundAssignOperator *E,
766 Value *(ScalarExprEmitter::*F)(const BinOpInfo &),
769 Value *EmitCompoundAssign(const CompoundAssignOperator *E,
770 Value *(ScalarExprEmitter::*F)(const BinOpInfo &));
772 // Binary operators and binary compound assignment operators.
773 #define HANDLEBINOP(OP) \
774 Value *VisitBin ## OP(const BinaryOperator *E) { \
775 return Emit ## OP(EmitBinOps(E)); \
777 Value *VisitBin ## OP ## Assign(const CompoundAssignOperator *E) { \
778 return EmitCompoundAssign(E, &ScalarExprEmitter::Emit ## OP); \
793 Value *EmitCompare(const BinaryOperator *E, llvm::CmpInst::Predicate UICmpOpc,
794 llvm::CmpInst::Predicate SICmpOpc,
795 llvm::CmpInst::Predicate FCmpOpc);
796 #define VISITCOMP(CODE, UI, SI, FP) \
797 Value *VisitBin##CODE(const BinaryOperator *E) { \
798 return EmitCompare(E, llvm::ICmpInst::UI, llvm::ICmpInst::SI, \
799 llvm::FCmpInst::FP); }
800 VISITCOMP(LT, ICMP_ULT, ICMP_SLT, FCMP_OLT)
801 VISITCOMP(GT, ICMP_UGT, ICMP_SGT, FCMP_OGT)
802 VISITCOMP(LE, ICMP_ULE, ICMP_SLE, FCMP_OLE)
803 VISITCOMP(GE, ICMP_UGE, ICMP_SGE, FCMP_OGE)
804 VISITCOMP(EQ, ICMP_EQ , ICMP_EQ , FCMP_OEQ)
805 VISITCOMP(NE, ICMP_NE , ICMP_NE , FCMP_UNE)
808 Value *VisitBinAssign (const BinaryOperator *E);
810 Value *VisitBinLAnd (const BinaryOperator *E);
811 Value *VisitBinLOr (const BinaryOperator *E);
812 Value *VisitBinComma (const BinaryOperator *E);
814 Value *VisitBinPtrMemD(const Expr *E) { return EmitLoadOfLValue(E); }
815 Value *VisitBinPtrMemI(const Expr *E) { return EmitLoadOfLValue(E); }
818 Value *VisitBlockExpr(const BlockExpr *BE);
819 Value *VisitAbstractConditionalOperator(const AbstractConditionalOperator *);
820 Value *VisitChooseExpr(ChooseExpr *CE);
821 Value *VisitVAArgExpr(VAArgExpr *VE);
822 Value *VisitObjCStringLiteral(const ObjCStringLiteral *E) {
823 return CGF.EmitObjCStringLiteral(E);
825 Value *VisitObjCBoxedExpr(ObjCBoxedExpr *E) {
826 return CGF.EmitObjCBoxedExpr(E);
828 Value *VisitObjCArrayLiteral(ObjCArrayLiteral *E) {
829 return CGF.EmitObjCArrayLiteral(E);
831 Value *VisitObjCDictionaryLiteral(ObjCDictionaryLiteral *E) {
832 return CGF.EmitObjCDictionaryLiteral(E);
834 Value *VisitAsTypeExpr(AsTypeExpr *CE);
835 Value *VisitAtomicExpr(AtomicExpr *AE);
837 } // end anonymous namespace.
839 //===----------------------------------------------------------------------===//
841 //===----------------------------------------------------------------------===//
843 /// EmitConversionToBool - Convert the specified expression value to a
844 /// boolean (i1) truth value. This is equivalent to "Val != 0".
845 Value *ScalarExprEmitter::EmitConversionToBool(Value *Src, QualType SrcType) {
846 assert(SrcType.isCanonical() && "EmitScalarConversion strips typedefs");
848 if (SrcType->isRealFloatingType())
849 return EmitFloatToBoolConversion(Src);
851 if (const MemberPointerType *MPT = dyn_cast<MemberPointerType>(SrcType))
852 return CGF.CGM.getCXXABI().EmitMemberPointerIsNotNull(CGF, Src, MPT);
854 assert((SrcType->isIntegerType() || isa<llvm::PointerType>(Src->getType())) &&
855 "Unknown scalar type to convert");
857 if (isa<llvm::IntegerType>(Src->getType()))
858 return EmitIntToBoolConversion(Src);
860 assert(isa<llvm::PointerType>(Src->getType()));
861 return EmitPointerToBoolConversion(Src, SrcType);
864 void ScalarExprEmitter::EmitFloatConversionCheck(
865 Value *OrigSrc, QualType OrigSrcType, Value *Src, QualType SrcType,
866 QualType DstType, llvm::Type *DstTy, SourceLocation Loc) {
867 assert(SrcType->isFloatingType() && "not a conversion from floating point");
868 if (!isa<llvm::IntegerType>(DstTy))
871 CodeGenFunction::SanitizerScope SanScope(&CGF);
875 llvm::Value *Check = nullptr;
876 const llvm::fltSemantics &SrcSema =
877 CGF.getContext().getFloatTypeSemantics(OrigSrcType);
879 // Floating-point to integer. This has undefined behavior if the source is
880 // +-Inf, NaN, or doesn't fit into the destination type (after truncation
882 unsigned Width = CGF.getContext().getIntWidth(DstType);
883 bool Unsigned = DstType->isUnsignedIntegerOrEnumerationType();
885 APSInt Min = APSInt::getMinValue(Width, Unsigned);
886 APFloat MinSrc(SrcSema, APFloat::uninitialized);
887 if (MinSrc.convertFromAPInt(Min, !Unsigned, APFloat::rmTowardZero) &
889 // Don't need an overflow check for lower bound. Just check for
891 MinSrc = APFloat::getInf(SrcSema, true);
893 // Find the largest value which is too small to represent (before
894 // truncation toward zero).
895 MinSrc.subtract(APFloat(SrcSema, 1), APFloat::rmTowardNegative);
897 APSInt Max = APSInt::getMaxValue(Width, Unsigned);
898 APFloat MaxSrc(SrcSema, APFloat::uninitialized);
899 if (MaxSrc.convertFromAPInt(Max, !Unsigned, APFloat::rmTowardZero) &
901 // Don't need an overflow check for upper bound. Just check for
903 MaxSrc = APFloat::getInf(SrcSema, false);
905 // Find the smallest value which is too large to represent (before
906 // truncation toward zero).
907 MaxSrc.add(APFloat(SrcSema, 1), APFloat::rmTowardPositive);
909 // If we're converting from __half, convert the range to float to match
911 if (OrigSrcType->isHalfType()) {
912 const llvm::fltSemantics &Sema =
913 CGF.getContext().getFloatTypeSemantics(SrcType);
915 MinSrc.convert(Sema, APFloat::rmTowardZero, &IsInexact);
916 MaxSrc.convert(Sema, APFloat::rmTowardZero, &IsInexact);
920 Builder.CreateFCmpOGT(Src, llvm::ConstantFP::get(VMContext, MinSrc));
922 Builder.CreateFCmpOLT(Src, llvm::ConstantFP::get(VMContext, MaxSrc));
923 Check = Builder.CreateAnd(GE, LE);
925 llvm::Constant *StaticArgs[] = {CGF.EmitCheckSourceLocation(Loc),
926 CGF.EmitCheckTypeDescriptor(OrigSrcType),
927 CGF.EmitCheckTypeDescriptor(DstType)};
928 CGF.EmitCheck(std::make_pair(Check, SanitizerKind::FloatCastOverflow),
929 SanitizerHandler::FloatCastOverflow, StaticArgs, OrigSrc);
932 // Should be called within CodeGenFunction::SanitizerScope RAII scope.
933 // Returns 'i1 false' when the truncation Src -> Dst was lossy.
934 static std::pair<ScalarExprEmitter::ImplicitConversionCheckKind,
935 std::pair<llvm::Value *, SanitizerMask>>
936 EmitIntegerTruncationCheckHelper(Value *Src, QualType SrcType, Value *Dst,
937 QualType DstType, CGBuilderTy &Builder) {
938 llvm::Type *SrcTy = Src->getType();
939 llvm::Type *DstTy = Dst->getType();
940 (void)DstTy; // Only used in assert()
942 // This should be truncation of integral types.
944 assert(SrcTy->getScalarSizeInBits() > Dst->getType()->getScalarSizeInBits());
945 assert(isa<llvm::IntegerType>(SrcTy) && isa<llvm::IntegerType>(DstTy) &&
946 "non-integer llvm type");
948 bool SrcSigned = SrcType->isSignedIntegerOrEnumerationType();
949 bool DstSigned = DstType->isSignedIntegerOrEnumerationType();
951 // If both (src and dst) types are unsigned, then it's an unsigned truncation.
952 // Else, it is a signed truncation.
953 ScalarExprEmitter::ImplicitConversionCheckKind Kind;
955 if (!SrcSigned && !DstSigned) {
956 Kind = ScalarExprEmitter::ICCK_UnsignedIntegerTruncation;
957 Mask = SanitizerKind::ImplicitUnsignedIntegerTruncation;
959 Kind = ScalarExprEmitter::ICCK_SignedIntegerTruncation;
960 Mask = SanitizerKind::ImplicitSignedIntegerTruncation;
963 llvm::Value *Check = nullptr;
964 // 1. Extend the truncated value back to the same width as the Src.
965 Check = Builder.CreateIntCast(Dst, SrcTy, DstSigned, "anyext");
966 // 2. Equality-compare with the original source value
967 Check = Builder.CreateICmpEQ(Check, Src, "truncheck");
968 // If the comparison result is 'i1 false', then the truncation was lossy.
969 return std::make_pair(Kind, std::make_pair(Check, Mask));
972 void ScalarExprEmitter::EmitIntegerTruncationCheck(Value *Src, QualType SrcType,
973 Value *Dst, QualType DstType,
974 SourceLocation Loc) {
975 if (!CGF.SanOpts.hasOneOf(SanitizerKind::ImplicitIntegerTruncation))
978 // We only care about int->int conversions here.
979 // We ignore conversions to/from pointer and/or bool.
980 if (!(SrcType->isIntegerType() && DstType->isIntegerType()))
983 unsigned SrcBits = Src->getType()->getScalarSizeInBits();
984 unsigned DstBits = Dst->getType()->getScalarSizeInBits();
985 // This must be truncation. Else we do not care.
986 if (SrcBits <= DstBits)
989 assert(!DstType->isBooleanType() && "we should not get here with booleans.");
991 // If the integer sign change sanitizer is enabled,
992 // and we are truncating from larger unsigned type to smaller signed type,
993 // let that next sanitizer deal with it.
994 bool SrcSigned = SrcType->isSignedIntegerOrEnumerationType();
995 bool DstSigned = DstType->isSignedIntegerOrEnumerationType();
996 if (CGF.SanOpts.has(SanitizerKind::ImplicitIntegerSignChange) &&
997 (!SrcSigned && DstSigned))
1000 CodeGenFunction::SanitizerScope SanScope(&CGF);
1002 std::pair<ScalarExprEmitter::ImplicitConversionCheckKind,
1003 std::pair<llvm::Value *, SanitizerMask>>
1005 EmitIntegerTruncationCheckHelper(Src, SrcType, Dst, DstType, Builder);
1006 // If the comparison result is 'i1 false', then the truncation was lossy.
1008 // Do we care about this type of truncation?
1009 if (!CGF.SanOpts.has(Check.second.second))
1012 llvm::Constant *StaticArgs[] = {
1013 CGF.EmitCheckSourceLocation(Loc), CGF.EmitCheckTypeDescriptor(SrcType),
1014 CGF.EmitCheckTypeDescriptor(DstType),
1015 llvm::ConstantInt::get(Builder.getInt8Ty(), Check.first)};
1016 CGF.EmitCheck(Check.second, SanitizerHandler::ImplicitConversion, StaticArgs,
1020 // Should be called within CodeGenFunction::SanitizerScope RAII scope.
1021 // Returns 'i1 false' when the conversion Src -> Dst changed the sign.
1022 static std::pair<ScalarExprEmitter::ImplicitConversionCheckKind,
1023 std::pair<llvm::Value *, SanitizerMask>>
1024 EmitIntegerSignChangeCheckHelper(Value *Src, QualType SrcType, Value *Dst,
1025 QualType DstType, CGBuilderTy &Builder) {
1026 llvm::Type *SrcTy = Src->getType();
1027 llvm::Type *DstTy = Dst->getType();
1029 assert(isa<llvm::IntegerType>(SrcTy) && isa<llvm::IntegerType>(DstTy) &&
1030 "non-integer llvm type");
1032 bool SrcSigned = SrcType->isSignedIntegerOrEnumerationType();
1033 bool DstSigned = DstType->isSignedIntegerOrEnumerationType();
1034 (void)SrcSigned; // Only used in assert()
1035 (void)DstSigned; // Only used in assert()
1036 unsigned SrcBits = SrcTy->getScalarSizeInBits();
1037 unsigned DstBits = DstTy->getScalarSizeInBits();
1038 (void)SrcBits; // Only used in assert()
1039 (void)DstBits; // Only used in assert()
1041 assert(((SrcBits != DstBits) || (SrcSigned != DstSigned)) &&
1042 "either the widths should be different, or the signednesses.");
1044 // NOTE: zero value is considered to be non-negative.
1045 auto EmitIsNegativeTest = [&Builder](Value *V, QualType VType,
1046 const char *Name) -> Value * {
1047 // Is this value a signed type?
1048 bool VSigned = VType->isSignedIntegerOrEnumerationType();
1049 llvm::Type *VTy = V->getType();
1051 // If the value is unsigned, then it is never negative.
1052 // FIXME: can we encounter non-scalar VTy here?
1053 return llvm::ConstantInt::getFalse(VTy->getContext());
1055 // Get the zero of the same type with which we will be comparing.
1056 llvm::Constant *Zero = llvm::ConstantInt::get(VTy, 0);
1057 // %V.isnegative = icmp slt %V, 0
1058 // I.e is %V *strictly* less than zero, does it have negative value?
1059 return Builder.CreateICmp(llvm::ICmpInst::ICMP_SLT, V, Zero,
1060 llvm::Twine(Name) + "." + V->getName() +
1061 ".negativitycheck");
1064 // 1. Was the old Value negative?
1065 llvm::Value *SrcIsNegative = EmitIsNegativeTest(Src, SrcType, "src");
1066 // 2. Is the new Value negative?
1067 llvm::Value *DstIsNegative = EmitIsNegativeTest(Dst, DstType, "dst");
1068 // 3. Now, was the 'negativity status' preserved during the conversion?
1069 // NOTE: conversion from negative to zero is considered to change the sign.
1070 // (We want to get 'false' when the conversion changed the sign)
1071 // So we should just equality-compare the negativity statuses.
1072 llvm::Value *Check = nullptr;
1073 Check = Builder.CreateICmpEQ(SrcIsNegative, DstIsNegative, "signchangecheck");
1074 // If the comparison result is 'false', then the conversion changed the sign.
1075 return std::make_pair(
1076 ScalarExprEmitter::ICCK_IntegerSignChange,
1077 std::make_pair(Check, SanitizerKind::ImplicitIntegerSignChange));
1080 void ScalarExprEmitter::EmitIntegerSignChangeCheck(Value *Src, QualType SrcType,
1081 Value *Dst, QualType DstType,
1082 SourceLocation Loc) {
1083 if (!CGF.SanOpts.has(SanitizerKind::ImplicitIntegerSignChange))
1086 llvm::Type *SrcTy = Src->getType();
1087 llvm::Type *DstTy = Dst->getType();
1089 // We only care about int->int conversions here.
1090 // We ignore conversions to/from pointer and/or bool.
1091 if (!(SrcType->isIntegerType() && DstType->isIntegerType()))
1094 bool SrcSigned = SrcType->isSignedIntegerOrEnumerationType();
1095 bool DstSigned = DstType->isSignedIntegerOrEnumerationType();
1096 unsigned SrcBits = SrcTy->getScalarSizeInBits();
1097 unsigned DstBits = DstTy->getScalarSizeInBits();
1099 // Now, we do not need to emit the check in *all* of the cases.
1100 // We can avoid emitting it in some obvious cases where it would have been
1101 // dropped by the opt passes (instcombine) always anyways.
1102 // If it's a cast between effectively the same type, no check.
1103 // NOTE: this is *not* equivalent to checking the canonical types.
1104 if (SrcSigned == DstSigned && SrcBits == DstBits)
1106 // At least one of the values needs to have signed type.
1107 // If both are unsigned, then obviously, neither of them can be negative.
1108 if (!SrcSigned && !DstSigned)
1110 // If the conversion is to *larger* *signed* type, then no check is needed.
1111 // Because either sign-extension happens (so the sign will remain),
1112 // or zero-extension will happen (the sign bit will be zero.)
1113 if ((DstBits > SrcBits) && DstSigned)
1115 if (CGF.SanOpts.has(SanitizerKind::ImplicitSignedIntegerTruncation) &&
1116 (SrcBits > DstBits) && SrcSigned) {
1117 // If the signed integer truncation sanitizer is enabled,
1118 // and this is a truncation from signed type, then no check is needed.
1119 // Because here sign change check is interchangeable with truncation check.
1122 // That's it. We can't rule out any more cases with the data we have.
1124 CodeGenFunction::SanitizerScope SanScope(&CGF);
1126 std::pair<ScalarExprEmitter::ImplicitConversionCheckKind,
1127 std::pair<llvm::Value *, SanitizerMask>>
1130 // Each of these checks needs to return 'false' when an issue was detected.
1131 ImplicitConversionCheckKind CheckKind;
1132 llvm::SmallVector<std::pair<llvm::Value *, SanitizerMask>, 2> Checks;
1133 // So we can 'and' all the checks together, and still get 'false',
1134 // if at least one of the checks detected an issue.
1136 Check = EmitIntegerSignChangeCheckHelper(Src, SrcType, Dst, DstType, Builder);
1137 CheckKind = Check.first;
1138 Checks.emplace_back(Check.second);
1140 if (CGF.SanOpts.has(SanitizerKind::ImplicitSignedIntegerTruncation) &&
1141 (SrcBits > DstBits) && !SrcSigned && DstSigned) {
1142 // If the signed integer truncation sanitizer was enabled,
1143 // and we are truncating from larger unsigned type to smaller signed type,
1144 // let's handle the case we skipped in that check.
1146 EmitIntegerTruncationCheckHelper(Src, SrcType, Dst, DstType, Builder);
1147 CheckKind = ICCK_SignedIntegerTruncationOrSignChange;
1148 Checks.emplace_back(Check.second);
1149 // If the comparison result is 'i1 false', then the truncation was lossy.
1152 llvm::Constant *StaticArgs[] = {
1153 CGF.EmitCheckSourceLocation(Loc), CGF.EmitCheckTypeDescriptor(SrcType),
1154 CGF.EmitCheckTypeDescriptor(DstType),
1155 llvm::ConstantInt::get(Builder.getInt8Ty(), CheckKind)};
1156 // EmitCheck() will 'and' all the checks together.
1157 CGF.EmitCheck(Checks, SanitizerHandler::ImplicitConversion, StaticArgs,
1161 /// Emit a conversion from the specified type to the specified destination type,
1162 /// both of which are LLVM scalar types.
1163 Value *ScalarExprEmitter::EmitScalarConversion(Value *Src, QualType SrcType,
1166 ScalarConversionOpts Opts) {
1167 // All conversions involving fixed point types should be handled by the
1168 // EmitFixedPoint family functions. This is done to prevent bloating up this
1169 // function more, and although fixed point numbers are represented by
1170 // integers, we do not want to follow any logic that assumes they should be
1171 // treated as integers.
1172 // TODO(leonardchan): When necessary, add another if statement checking for
1173 // conversions to fixed point types from other types.
1174 if (SrcType->isFixedPointType()) {
1175 if (DstType->isBooleanType())
1176 // It is important that we check this before checking if the dest type is
1177 // an integer because booleans are technically integer types.
1178 // We do not need to check the padding bit on unsigned types if unsigned
1179 // padding is enabled because overflow into this bit is undefined
1181 return Builder.CreateIsNotNull(Src, "tobool");
1182 if (DstType->isFixedPointType() || DstType->isIntegerType())
1183 return EmitFixedPointConversion(Src, SrcType, DstType, Loc);
1186 "Unhandled scalar conversion from a fixed point type to another type.");
1187 } else if (DstType->isFixedPointType()) {
1188 if (SrcType->isIntegerType())
1189 // This also includes converting booleans and enums to fixed point types.
1190 return EmitFixedPointConversion(Src, SrcType, DstType, Loc);
1193 "Unhandled scalar conversion to a fixed point type from another type.");
1196 QualType NoncanonicalSrcType = SrcType;
1197 QualType NoncanonicalDstType = DstType;
1199 SrcType = CGF.getContext().getCanonicalType(SrcType);
1200 DstType = CGF.getContext().getCanonicalType(DstType);
1201 if (SrcType == DstType) return Src;
1203 if (DstType->isVoidType()) return nullptr;
1205 llvm::Value *OrigSrc = Src;
1206 QualType OrigSrcType = SrcType;
1207 llvm::Type *SrcTy = Src->getType();
1209 // Handle conversions to bool first, they are special: comparisons against 0.
1210 if (DstType->isBooleanType())
1211 return EmitConversionToBool(Src, SrcType);
1213 llvm::Type *DstTy = ConvertType(DstType);
1215 // Cast from half through float if half isn't a native type.
1216 if (SrcType->isHalfType() && !CGF.getContext().getLangOpts().NativeHalfType) {
1217 // Cast to FP using the intrinsic if the half type itself isn't supported.
1218 if (DstTy->isFloatingPointTy()) {
1219 if (CGF.getContext().getTargetInfo().useFP16ConversionIntrinsics())
1220 return Builder.CreateCall(
1221 CGF.CGM.getIntrinsic(llvm::Intrinsic::convert_from_fp16, DstTy),
1224 // Cast to other types through float, using either the intrinsic or FPExt,
1225 // depending on whether the half type itself is supported
1226 // (as opposed to operations on half, available with NativeHalfType).
1227 if (CGF.getContext().getTargetInfo().useFP16ConversionIntrinsics()) {
1228 Src = Builder.CreateCall(
1229 CGF.CGM.getIntrinsic(llvm::Intrinsic::convert_from_fp16,
1233 Src = Builder.CreateFPExt(Src, CGF.CGM.FloatTy, "conv");
1235 SrcType = CGF.getContext().FloatTy;
1236 SrcTy = CGF.FloatTy;
1240 // Ignore conversions like int -> uint.
1241 if (SrcTy == DstTy) {
1242 if (Opts.EmitImplicitIntegerSignChangeChecks)
1243 EmitIntegerSignChangeCheck(Src, NoncanonicalSrcType, Src,
1244 NoncanonicalDstType, Loc);
1249 // Handle pointer conversions next: pointers can only be converted to/from
1250 // other pointers and integers. Check for pointer types in terms of LLVM, as
1251 // some native types (like Obj-C id) may map to a pointer type.
1252 if (auto DstPT = dyn_cast<llvm::PointerType>(DstTy)) {
1253 // The source value may be an integer, or a pointer.
1254 if (isa<llvm::PointerType>(SrcTy))
1255 return Builder.CreateBitCast(Src, DstTy, "conv");
1257 assert(SrcType->isIntegerType() && "Not ptr->ptr or int->ptr conversion?");
1258 // First, convert to the correct width so that we control the kind of
1260 llvm::Type *MiddleTy = CGF.CGM.getDataLayout().getIntPtrType(DstPT);
1261 bool InputSigned = SrcType->isSignedIntegerOrEnumerationType();
1262 llvm::Value* IntResult =
1263 Builder.CreateIntCast(Src, MiddleTy, InputSigned, "conv");
1264 // Then, cast to pointer.
1265 return Builder.CreateIntToPtr(IntResult, DstTy, "conv");
1268 if (isa<llvm::PointerType>(SrcTy)) {
1269 // Must be an ptr to int cast.
1270 assert(isa<llvm::IntegerType>(DstTy) && "not ptr->int?");
1271 return Builder.CreatePtrToInt(Src, DstTy, "conv");
1274 // A scalar can be splatted to an extended vector of the same element type
1275 if (DstType->isExtVectorType() && !SrcType->isVectorType()) {
1276 // Sema should add casts to make sure that the source expression's type is
1277 // the same as the vector's element type (sans qualifiers)
1278 assert(DstType->castAs<ExtVectorType>()->getElementType().getTypePtr() ==
1279 SrcType.getTypePtr() &&
1280 "Splatted expr doesn't match with vector element type?");
1282 // Splat the element across to all elements
1283 unsigned NumElements = DstTy->getVectorNumElements();
1284 return Builder.CreateVectorSplat(NumElements, Src, "splat");
1287 if (isa<llvm::VectorType>(SrcTy) || isa<llvm::VectorType>(DstTy)) {
1288 // Allow bitcast from vector to integer/fp of the same size.
1289 unsigned SrcSize = SrcTy->getPrimitiveSizeInBits();
1290 unsigned DstSize = DstTy->getPrimitiveSizeInBits();
1291 if (SrcSize == DstSize)
1292 return Builder.CreateBitCast(Src, DstTy, "conv");
1294 // Conversions between vectors of different sizes are not allowed except
1295 // when vectors of half are involved. Operations on storage-only half
1296 // vectors require promoting half vector operands to float vectors and
1297 // truncating the result, which is either an int or float vector, to a
1298 // short or half vector.
1300 // Source and destination are both expected to be vectors.
1301 llvm::Type *SrcElementTy = SrcTy->getVectorElementType();
1302 llvm::Type *DstElementTy = DstTy->getVectorElementType();
1305 assert(((SrcElementTy->isIntegerTy() &&
1306 DstElementTy->isIntegerTy()) ||
1307 (SrcElementTy->isFloatingPointTy() &&
1308 DstElementTy->isFloatingPointTy())) &&
1309 "unexpected conversion between a floating-point vector and an "
1312 // Truncate an i32 vector to an i16 vector.
1313 if (SrcElementTy->isIntegerTy())
1314 return Builder.CreateIntCast(Src, DstTy, false, "conv");
1316 // Truncate a float vector to a half vector.
1317 if (SrcSize > DstSize)
1318 return Builder.CreateFPTrunc(Src, DstTy, "conv");
1320 // Promote a half vector to a float vector.
1321 return Builder.CreateFPExt(Src, DstTy, "conv");
1324 // Finally, we have the arithmetic types: real int/float.
1325 Value *Res = nullptr;
1326 llvm::Type *ResTy = DstTy;
1328 // An overflowing conversion has undefined behavior if either the source type
1329 // or the destination type is a floating-point type. However, we consider the
1330 // range of representable values for all floating-point types to be
1331 // [-inf,+inf], so no overflow can ever happen when the destination type is a
1332 // floating-point type.
1333 if (CGF.SanOpts.has(SanitizerKind::FloatCastOverflow) &&
1334 OrigSrcType->isFloatingType())
1335 EmitFloatConversionCheck(OrigSrc, OrigSrcType, Src, SrcType, DstType, DstTy,
1338 // Cast to half through float if half isn't a native type.
1339 if (DstType->isHalfType() && !CGF.getContext().getLangOpts().NativeHalfType) {
1340 // Make sure we cast in a single step if from another FP type.
1341 if (SrcTy->isFloatingPointTy()) {
1342 // Use the intrinsic if the half type itself isn't supported
1343 // (as opposed to operations on half, available with NativeHalfType).
1344 if (CGF.getContext().getTargetInfo().useFP16ConversionIntrinsics())
1345 return Builder.CreateCall(
1346 CGF.CGM.getIntrinsic(llvm::Intrinsic::convert_to_fp16, SrcTy), Src);
1347 // If the half type is supported, just use an fptrunc.
1348 return Builder.CreateFPTrunc(Src, DstTy);
1350 DstTy = CGF.FloatTy;
1353 if (isa<llvm::IntegerType>(SrcTy)) {
1354 bool InputSigned = SrcType->isSignedIntegerOrEnumerationType();
1355 if (SrcType->isBooleanType() && Opts.TreatBooleanAsSigned) {
1358 if (isa<llvm::IntegerType>(DstTy))
1359 Res = Builder.CreateIntCast(Src, DstTy, InputSigned, "conv");
1360 else if (InputSigned)
1361 Res = Builder.CreateSIToFP(Src, DstTy, "conv");
1363 Res = Builder.CreateUIToFP(Src, DstTy, "conv");
1364 } else if (isa<llvm::IntegerType>(DstTy)) {
1365 assert(SrcTy->isFloatingPointTy() && "Unknown real conversion");
1366 if (DstType->isSignedIntegerOrEnumerationType())
1367 Res = Builder.CreateFPToSI(Src, DstTy, "conv");
1369 Res = Builder.CreateFPToUI(Src, DstTy, "conv");
1371 assert(SrcTy->isFloatingPointTy() && DstTy->isFloatingPointTy() &&
1372 "Unknown real conversion");
1373 if (DstTy->getTypeID() < SrcTy->getTypeID())
1374 Res = Builder.CreateFPTrunc(Src, DstTy, "conv");
1376 Res = Builder.CreateFPExt(Src, DstTy, "conv");
1379 if (DstTy != ResTy) {
1380 if (CGF.getContext().getTargetInfo().useFP16ConversionIntrinsics()) {
1381 assert(ResTy->isIntegerTy(16) && "Only half FP requires extra conversion");
1382 Res = Builder.CreateCall(
1383 CGF.CGM.getIntrinsic(llvm::Intrinsic::convert_to_fp16, CGF.CGM.FloatTy),
1386 Res = Builder.CreateFPTrunc(Res, ResTy, "conv");
1390 if (Opts.EmitImplicitIntegerTruncationChecks)
1391 EmitIntegerTruncationCheck(Src, NoncanonicalSrcType, Res,
1392 NoncanonicalDstType, Loc);
1394 if (Opts.EmitImplicitIntegerSignChangeChecks)
1395 EmitIntegerSignChangeCheck(Src, NoncanonicalSrcType, Res,
1396 NoncanonicalDstType, Loc);
1401 Value *ScalarExprEmitter::EmitFixedPointConversion(Value *Src, QualType SrcTy,
1403 SourceLocation Loc) {
1404 FixedPointSemantics SrcFPSema =
1405 CGF.getContext().getFixedPointSemantics(SrcTy);
1406 FixedPointSemantics DstFPSema =
1407 CGF.getContext().getFixedPointSemantics(DstTy);
1408 return EmitFixedPointConversion(Src, SrcFPSema, DstFPSema, Loc,
1409 DstTy->isIntegerType());
1412 Value *ScalarExprEmitter::EmitFixedPointConversion(
1413 Value *Src, FixedPointSemantics &SrcFPSema, FixedPointSemantics &DstFPSema,
1414 SourceLocation Loc, bool DstIsInteger) {
1416 using llvm::ConstantInt;
1419 unsigned SrcWidth = SrcFPSema.getWidth();
1420 unsigned DstWidth = DstFPSema.getWidth();
1421 unsigned SrcScale = SrcFPSema.getScale();
1422 unsigned DstScale = DstFPSema.getScale();
1423 bool SrcIsSigned = SrcFPSema.isSigned();
1424 bool DstIsSigned = DstFPSema.isSigned();
1426 llvm::Type *DstIntTy = Builder.getIntNTy(DstWidth);
1428 Value *Result = Src;
1429 unsigned ResultWidth = SrcWidth;
1432 if (DstScale < SrcScale) {
1433 // When converting to integers, we round towards zero. For negative numbers,
1434 // right shifting rounds towards negative infinity. In this case, we can
1435 // just round up before shifting.
1436 if (DstIsInteger && SrcIsSigned) {
1437 Value *Zero = llvm::Constant::getNullValue(Result->getType());
1438 Value *IsNegative = Builder.CreateICmpSLT(Result, Zero);
1439 Value *LowBits = ConstantInt::get(
1440 CGF.getLLVMContext(), APInt::getLowBitsSet(ResultWidth, SrcScale));
1441 Value *Rounded = Builder.CreateAdd(Result, LowBits);
1442 Result = Builder.CreateSelect(IsNegative, Rounded, Result);
1445 Result = SrcIsSigned
1446 ? Builder.CreateAShr(Result, SrcScale - DstScale, "downscale")
1447 : Builder.CreateLShr(Result, SrcScale - DstScale, "downscale");
1450 if (!DstFPSema.isSaturated()) {
1452 Result = Builder.CreateIntCast(Result, DstIntTy, SrcIsSigned, "resize");
1455 if (DstScale > SrcScale)
1456 Result = Builder.CreateShl(Result, DstScale - SrcScale, "upscale");
1458 // Adjust the number of fractional bits.
1459 if (DstScale > SrcScale) {
1460 // Compare to DstWidth to prevent resizing twice.
1461 ResultWidth = std::max(SrcWidth + DstScale - SrcScale, DstWidth);
1462 llvm::Type *UpscaledTy = Builder.getIntNTy(ResultWidth);
1463 Result = Builder.CreateIntCast(Result, UpscaledTy, SrcIsSigned, "resize");
1464 Result = Builder.CreateShl(Result, DstScale - SrcScale, "upscale");
1467 // Handle saturation.
1468 bool LessIntBits = DstFPSema.getIntegralBits() < SrcFPSema.getIntegralBits();
1470 Value *Max = ConstantInt::get(
1471 CGF.getLLVMContext(),
1472 APFixedPoint::getMax(DstFPSema).getValue().extOrTrunc(ResultWidth));
1473 Value *TooHigh = SrcIsSigned ? Builder.CreateICmpSGT(Result, Max)
1474 : Builder.CreateICmpUGT(Result, Max);
1475 Result = Builder.CreateSelect(TooHigh, Max, Result, "satmax");
1477 // Cannot overflow min to dest type if src is unsigned since all fixed
1478 // point types can cover the unsigned min of 0.
1479 if (SrcIsSigned && (LessIntBits || !DstIsSigned)) {
1480 Value *Min = ConstantInt::get(
1481 CGF.getLLVMContext(),
1482 APFixedPoint::getMin(DstFPSema).getValue().extOrTrunc(ResultWidth));
1483 Value *TooLow = Builder.CreateICmpSLT(Result, Min);
1484 Result = Builder.CreateSelect(TooLow, Min, Result, "satmin");
1487 // Resize the integer part to get the final destination size.
1488 if (ResultWidth != DstWidth)
1489 Result = Builder.CreateIntCast(Result, DstIntTy, SrcIsSigned, "resize");
1494 /// Emit a conversion from the specified complex type to the specified
1495 /// destination type, where the destination type is an LLVM scalar type.
1496 Value *ScalarExprEmitter::EmitComplexToScalarConversion(
1497 CodeGenFunction::ComplexPairTy Src, QualType SrcTy, QualType DstTy,
1498 SourceLocation Loc) {
1499 // Get the source element type.
1500 SrcTy = SrcTy->castAs<ComplexType>()->getElementType();
1502 // Handle conversions to bool first, they are special: comparisons against 0.
1503 if (DstTy->isBooleanType()) {
1504 // Complex != 0 -> (Real != 0) | (Imag != 0)
1505 Src.first = EmitScalarConversion(Src.first, SrcTy, DstTy, Loc);
1506 Src.second = EmitScalarConversion(Src.second, SrcTy, DstTy, Loc);
1507 return Builder.CreateOr(Src.first, Src.second, "tobool");
1510 // C99 6.3.1.7p2: "When a value of complex type is converted to a real type,
1511 // the imaginary part of the complex value is discarded and the value of the
1512 // real part is converted according to the conversion rules for the
1513 // corresponding real type.
1514 return EmitScalarConversion(Src.first, SrcTy, DstTy, Loc);
1517 Value *ScalarExprEmitter::EmitNullValue(QualType Ty) {
1518 return CGF.EmitFromMemory(CGF.CGM.EmitNullConstant(Ty), Ty);
1521 /// Emit a sanitization check for the given "binary" operation (which
1522 /// might actually be a unary increment which has been lowered to a binary
1523 /// operation). The check passes if all values in \p Checks (which are \c i1),
1525 void ScalarExprEmitter::EmitBinOpCheck(
1526 ArrayRef<std::pair<Value *, SanitizerMask>> Checks, const BinOpInfo &Info) {
1527 assert(CGF.IsSanitizerScope);
1528 SanitizerHandler Check;
1529 SmallVector<llvm::Constant *, 4> StaticData;
1530 SmallVector<llvm::Value *, 2> DynamicData;
1532 BinaryOperatorKind Opcode = Info.Opcode;
1533 if (BinaryOperator::isCompoundAssignmentOp(Opcode))
1534 Opcode = BinaryOperator::getOpForCompoundAssignment(Opcode);
1536 StaticData.push_back(CGF.EmitCheckSourceLocation(Info.E->getExprLoc()));
1537 const UnaryOperator *UO = dyn_cast<UnaryOperator>(Info.E);
1538 if (UO && UO->getOpcode() == UO_Minus) {
1539 Check = SanitizerHandler::NegateOverflow;
1540 StaticData.push_back(CGF.EmitCheckTypeDescriptor(UO->getType()));
1541 DynamicData.push_back(Info.RHS);
1543 if (BinaryOperator::isShiftOp(Opcode)) {
1544 // Shift LHS negative or too large, or RHS out of bounds.
1545 Check = SanitizerHandler::ShiftOutOfBounds;
1546 const BinaryOperator *BO = cast<BinaryOperator>(Info.E);
1547 StaticData.push_back(
1548 CGF.EmitCheckTypeDescriptor(BO->getLHS()->getType()));
1549 StaticData.push_back(
1550 CGF.EmitCheckTypeDescriptor(BO->getRHS()->getType()));
1551 } else if (Opcode == BO_Div || Opcode == BO_Rem) {
1552 // Divide or modulo by zero, or signed overflow (eg INT_MAX / -1).
1553 Check = SanitizerHandler::DivremOverflow;
1554 StaticData.push_back(CGF.EmitCheckTypeDescriptor(Info.Ty));
1556 // Arithmetic overflow (+, -, *).
1558 case BO_Add: Check = SanitizerHandler::AddOverflow; break;
1559 case BO_Sub: Check = SanitizerHandler::SubOverflow; break;
1560 case BO_Mul: Check = SanitizerHandler::MulOverflow; break;
1561 default: llvm_unreachable("unexpected opcode for bin op check");
1563 StaticData.push_back(CGF.EmitCheckTypeDescriptor(Info.Ty));
1565 DynamicData.push_back(Info.LHS);
1566 DynamicData.push_back(Info.RHS);
1569 CGF.EmitCheck(Checks, Check, StaticData, DynamicData);
1572 //===----------------------------------------------------------------------===//
1574 //===----------------------------------------------------------------------===//
1576 Value *ScalarExprEmitter::VisitExpr(Expr *E) {
1577 CGF.ErrorUnsupported(E, "scalar expression");
1578 if (E->getType()->isVoidType())
1580 return llvm::UndefValue::get(CGF.ConvertType(E->getType()));
1583 Value *ScalarExprEmitter::VisitShuffleVectorExpr(ShuffleVectorExpr *E) {
1585 if (E->getNumSubExprs() == 2) {
1586 Value *LHS = CGF.EmitScalarExpr(E->getExpr(0));
1587 Value *RHS = CGF.EmitScalarExpr(E->getExpr(1));
1590 llvm::VectorType *LTy = cast<llvm::VectorType>(LHS->getType());
1591 unsigned LHSElts = LTy->getNumElements();
1595 llvm::VectorType *MTy = cast<llvm::VectorType>(Mask->getType());
1597 // Mask off the high bits of each shuffle index.
1599 llvm::ConstantInt::get(MTy, llvm::NextPowerOf2(LHSElts - 1) - 1);
1600 Mask = Builder.CreateAnd(Mask, MaskBits, "mask");
1603 // mask = mask & maskbits
1605 // n = extract mask i
1606 // x = extract val n
1607 // newv = insert newv, x, i
1608 llvm::VectorType *RTy = llvm::VectorType::get(LTy->getElementType(),
1609 MTy->getNumElements());
1610 Value* NewV = llvm::UndefValue::get(RTy);
1611 for (unsigned i = 0, e = MTy->getNumElements(); i != e; ++i) {
1612 Value *IIndx = llvm::ConstantInt::get(CGF.SizeTy, i);
1613 Value *Indx = Builder.CreateExtractElement(Mask, IIndx, "shuf_idx");
1615 Value *VExt = Builder.CreateExtractElement(LHS, Indx, "shuf_elt");
1616 NewV = Builder.CreateInsertElement(NewV, VExt, IIndx, "shuf_ins");
1621 Value* V1 = CGF.EmitScalarExpr(E->getExpr(0));
1622 Value* V2 = CGF.EmitScalarExpr(E->getExpr(1));
1624 SmallVector<llvm::Constant*, 32> indices;
1625 for (unsigned i = 2; i < E->getNumSubExprs(); ++i) {
1626 llvm::APSInt Idx = E->getShuffleMaskIdx(CGF.getContext(), i-2);
1627 // Check for -1 and output it as undef in the IR.
1628 if (Idx.isSigned() && Idx.isAllOnesValue())
1629 indices.push_back(llvm::UndefValue::get(CGF.Int32Ty));
1631 indices.push_back(Builder.getInt32(Idx.getZExtValue()));
1634 Value *SV = llvm::ConstantVector::get(indices);
1635 return Builder.CreateShuffleVector(V1, V2, SV, "shuffle");
1638 Value *ScalarExprEmitter::VisitConvertVectorExpr(ConvertVectorExpr *E) {
1639 QualType SrcType = E->getSrcExpr()->getType(),
1640 DstType = E->getType();
1642 Value *Src = CGF.EmitScalarExpr(E->getSrcExpr());
1644 SrcType = CGF.getContext().getCanonicalType(SrcType);
1645 DstType = CGF.getContext().getCanonicalType(DstType);
1646 if (SrcType == DstType) return Src;
1648 assert(SrcType->isVectorType() &&
1649 "ConvertVector source type must be a vector");
1650 assert(DstType->isVectorType() &&
1651 "ConvertVector destination type must be a vector");
1653 llvm::Type *SrcTy = Src->getType();
1654 llvm::Type *DstTy = ConvertType(DstType);
1656 // Ignore conversions like int -> uint.
1660 QualType SrcEltType = SrcType->getAs<VectorType>()->getElementType(),
1661 DstEltType = DstType->getAs<VectorType>()->getElementType();
1663 assert(SrcTy->isVectorTy() &&
1664 "ConvertVector source IR type must be a vector");
1665 assert(DstTy->isVectorTy() &&
1666 "ConvertVector destination IR type must be a vector");
1668 llvm::Type *SrcEltTy = SrcTy->getVectorElementType(),
1669 *DstEltTy = DstTy->getVectorElementType();
1671 if (DstEltType->isBooleanType()) {
1672 assert((SrcEltTy->isFloatingPointTy() ||
1673 isa<llvm::IntegerType>(SrcEltTy)) && "Unknown boolean conversion");
1675 llvm::Value *Zero = llvm::Constant::getNullValue(SrcTy);
1676 if (SrcEltTy->isFloatingPointTy()) {
1677 return Builder.CreateFCmpUNE(Src, Zero, "tobool");
1679 return Builder.CreateICmpNE(Src, Zero, "tobool");
1683 // We have the arithmetic types: real int/float.
1684 Value *Res = nullptr;
1686 if (isa<llvm::IntegerType>(SrcEltTy)) {
1687 bool InputSigned = SrcEltType->isSignedIntegerOrEnumerationType();
1688 if (isa<llvm::IntegerType>(DstEltTy))
1689 Res = Builder.CreateIntCast(Src, DstTy, InputSigned, "conv");
1690 else if (InputSigned)
1691 Res = Builder.CreateSIToFP(Src, DstTy, "conv");
1693 Res = Builder.CreateUIToFP(Src, DstTy, "conv");
1694 } else if (isa<llvm::IntegerType>(DstEltTy)) {
1695 assert(SrcEltTy->isFloatingPointTy() && "Unknown real conversion");
1696 if (DstEltType->isSignedIntegerOrEnumerationType())
1697 Res = Builder.CreateFPToSI(Src, DstTy, "conv");
1699 Res = Builder.CreateFPToUI(Src, DstTy, "conv");
1701 assert(SrcEltTy->isFloatingPointTy() && DstEltTy->isFloatingPointTy() &&
1702 "Unknown real conversion");
1703 if (DstEltTy->getTypeID() < SrcEltTy->getTypeID())
1704 Res = Builder.CreateFPTrunc(Src, DstTy, "conv");
1706 Res = Builder.CreateFPExt(Src, DstTy, "conv");
1712 Value *ScalarExprEmitter::VisitMemberExpr(MemberExpr *E) {
1713 if (CodeGenFunction::ConstantEmission Constant = CGF.tryEmitAsConstant(E)) {
1714 CGF.EmitIgnoredExpr(E->getBase());
1715 return CGF.emitScalarConstant(Constant, E);
1717 Expr::EvalResult Result;
1718 if (E->EvaluateAsInt(Result, CGF.getContext(), Expr::SE_AllowSideEffects)) {
1719 llvm::APSInt Value = Result.Val.getInt();
1720 CGF.EmitIgnoredExpr(E->getBase());
1721 return Builder.getInt(Value);
1725 return EmitLoadOfLValue(E);
1728 Value *ScalarExprEmitter::VisitArraySubscriptExpr(ArraySubscriptExpr *E) {
1729 TestAndClearIgnoreResultAssign();
1731 // Emit subscript expressions in rvalue context's. For most cases, this just
1732 // loads the lvalue formed by the subscript expr. However, we have to be
1733 // careful, because the base of a vector subscript is occasionally an rvalue,
1734 // so we can't get it as an lvalue.
1735 if (!E->getBase()->getType()->isVectorType())
1736 return EmitLoadOfLValue(E);
1738 // Handle the vector case. The base must be a vector, the index must be an
1740 Value *Base = Visit(E->getBase());
1741 Value *Idx = Visit(E->getIdx());
1742 QualType IdxTy = E->getIdx()->getType();
1744 if (CGF.SanOpts.has(SanitizerKind::ArrayBounds))
1745 CGF.EmitBoundsCheck(E, E->getBase(), Idx, IdxTy, /*Accessed*/true);
1747 return Builder.CreateExtractElement(Base, Idx, "vecext");
1750 static llvm::Constant *getMaskElt(llvm::ShuffleVectorInst *SVI, unsigned Idx,
1751 unsigned Off, llvm::Type *I32Ty) {
1752 int MV = SVI->getMaskValue(Idx);
1754 return llvm::UndefValue::get(I32Ty);
1755 return llvm::ConstantInt::get(I32Ty, Off+MV);
1758 static llvm::Constant *getAsInt32(llvm::ConstantInt *C, llvm::Type *I32Ty) {
1759 if (C->getBitWidth() != 32) {
1760 assert(llvm::ConstantInt::isValueValidForType(I32Ty,
1761 C->getZExtValue()) &&
1762 "Index operand too large for shufflevector mask!");
1763 return llvm::ConstantInt::get(I32Ty, C->getZExtValue());
1768 Value *ScalarExprEmitter::VisitInitListExpr(InitListExpr *E) {
1769 bool Ignore = TestAndClearIgnoreResultAssign();
1771 assert (Ignore == false && "init list ignored");
1772 unsigned NumInitElements = E->getNumInits();
1774 if (E->hadArrayRangeDesignator())
1775 CGF.ErrorUnsupported(E, "GNU array range designator extension");
1777 llvm::VectorType *VType =
1778 dyn_cast<llvm::VectorType>(ConvertType(E->getType()));
1781 if (NumInitElements == 0) {
1782 // C++11 value-initialization for the scalar.
1783 return EmitNullValue(E->getType());
1785 // We have a scalar in braces. Just use the first element.
1786 return Visit(E->getInit(0));
1789 unsigned ResElts = VType->getNumElements();
1791 // Loop over initializers collecting the Value for each, and remembering
1792 // whether the source was swizzle (ExtVectorElementExpr). This will allow
1793 // us to fold the shuffle for the swizzle into the shuffle for the vector
1794 // initializer, since LLVM optimizers generally do not want to touch
1796 unsigned CurIdx = 0;
1797 bool VIsUndefShuffle = false;
1798 llvm::Value *V = llvm::UndefValue::get(VType);
1799 for (unsigned i = 0; i != NumInitElements; ++i) {
1800 Expr *IE = E->getInit(i);
1801 Value *Init = Visit(IE);
1802 SmallVector<llvm::Constant*, 16> Args;
1804 llvm::VectorType *VVT = dyn_cast<llvm::VectorType>(Init->getType());
1806 // Handle scalar elements. If the scalar initializer is actually one
1807 // element of a different vector of the same width, use shuffle instead of
1810 if (isa<ExtVectorElementExpr>(IE)) {
1811 llvm::ExtractElementInst *EI = cast<llvm::ExtractElementInst>(Init);
1813 if (EI->getVectorOperandType()->getNumElements() == ResElts) {
1814 llvm::ConstantInt *C = cast<llvm::ConstantInt>(EI->getIndexOperand());
1815 Value *LHS = nullptr, *RHS = nullptr;
1817 // insert into undef -> shuffle (src, undef)
1818 // shufflemask must use an i32
1819 Args.push_back(getAsInt32(C, CGF.Int32Ty));
1820 Args.resize(ResElts, llvm::UndefValue::get(CGF.Int32Ty));
1822 LHS = EI->getVectorOperand();
1824 VIsUndefShuffle = true;
1825 } else if (VIsUndefShuffle) {
1826 // insert into undefshuffle && size match -> shuffle (v, src)
1827 llvm::ShuffleVectorInst *SVV = cast<llvm::ShuffleVectorInst>(V);
1828 for (unsigned j = 0; j != CurIdx; ++j)
1829 Args.push_back(getMaskElt(SVV, j, 0, CGF.Int32Ty));
1830 Args.push_back(Builder.getInt32(ResElts + C->getZExtValue()));
1831 Args.resize(ResElts, llvm::UndefValue::get(CGF.Int32Ty));
1833 LHS = cast<llvm::ShuffleVectorInst>(V)->getOperand(0);
1834 RHS = EI->getVectorOperand();
1835 VIsUndefShuffle = false;
1837 if (!Args.empty()) {
1838 llvm::Constant *Mask = llvm::ConstantVector::get(Args);
1839 V = Builder.CreateShuffleVector(LHS, RHS, Mask);
1845 V = Builder.CreateInsertElement(V, Init, Builder.getInt32(CurIdx),
1847 VIsUndefShuffle = false;
1852 unsigned InitElts = VVT->getNumElements();
1854 // If the initializer is an ExtVecEltExpr (a swizzle), and the swizzle's
1855 // input is the same width as the vector being constructed, generate an
1856 // optimized shuffle of the swizzle input into the result.
1857 unsigned Offset = (CurIdx == 0) ? 0 : ResElts;
1858 if (isa<ExtVectorElementExpr>(IE)) {
1859 llvm::ShuffleVectorInst *SVI = cast<llvm::ShuffleVectorInst>(Init);
1860 Value *SVOp = SVI->getOperand(0);
1861 llvm::VectorType *OpTy = cast<llvm::VectorType>(SVOp->getType());
1863 if (OpTy->getNumElements() == ResElts) {
1864 for (unsigned j = 0; j != CurIdx; ++j) {
1865 // If the current vector initializer is a shuffle with undef, merge
1866 // this shuffle directly into it.
1867 if (VIsUndefShuffle) {
1868 Args.push_back(getMaskElt(cast<llvm::ShuffleVectorInst>(V), j, 0,
1871 Args.push_back(Builder.getInt32(j));
1874 for (unsigned j = 0, je = InitElts; j != je; ++j)
1875 Args.push_back(getMaskElt(SVI, j, Offset, CGF.Int32Ty));
1876 Args.resize(ResElts, llvm::UndefValue::get(CGF.Int32Ty));
1878 if (VIsUndefShuffle)
1879 V = cast<llvm::ShuffleVectorInst>(V)->getOperand(0);
1885 // Extend init to result vector length, and then shuffle its contribution
1886 // to the vector initializer into V.
1888 for (unsigned j = 0; j != InitElts; ++j)
1889 Args.push_back(Builder.getInt32(j));
1890 Args.resize(ResElts, llvm::UndefValue::get(CGF.Int32Ty));
1891 llvm::Constant *Mask = llvm::ConstantVector::get(Args);
1892 Init = Builder.CreateShuffleVector(Init, llvm::UndefValue::get(VVT),
1896 for (unsigned j = 0; j != CurIdx; ++j)
1897 Args.push_back(Builder.getInt32(j));
1898 for (unsigned j = 0; j != InitElts; ++j)
1899 Args.push_back(Builder.getInt32(j+Offset));
1900 Args.resize(ResElts, llvm::UndefValue::get(CGF.Int32Ty));
1903 // If V is undef, make sure it ends up on the RHS of the shuffle to aid
1904 // merging subsequent shuffles into this one.
1907 llvm::Constant *Mask = llvm::ConstantVector::get(Args);
1908 V = Builder.CreateShuffleVector(V, Init, Mask, "vecinit");
1909 VIsUndefShuffle = isa<llvm::UndefValue>(Init);
1913 // FIXME: evaluate codegen vs. shuffling against constant null vector.
1914 // Emit remaining default initializers.
1915 llvm::Type *EltTy = VType->getElementType();
1917 // Emit remaining default initializers
1918 for (/* Do not initialize i*/; CurIdx < ResElts; ++CurIdx) {
1919 Value *Idx = Builder.getInt32(CurIdx);
1920 llvm::Value *Init = llvm::Constant::getNullValue(EltTy);
1921 V = Builder.CreateInsertElement(V, Init, Idx, "vecinit");
1926 bool CodeGenFunction::ShouldNullCheckClassCastValue(const CastExpr *CE) {
1927 const Expr *E = CE->getSubExpr();
1929 if (CE->getCastKind() == CK_UncheckedDerivedToBase)
1932 if (isa<CXXThisExpr>(E->IgnoreParens())) {
1933 // We always assume that 'this' is never null.
1937 if (const ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(CE)) {
1938 // And that glvalue casts are never null.
1939 if (ICE->getValueKind() != VK_RValue)
1946 // VisitCastExpr - Emit code for an explicit or implicit cast. Implicit casts
1947 // have to handle a more broad range of conversions than explicit casts, as they
1948 // handle things like function to ptr-to-function decay etc.
1949 Value *ScalarExprEmitter::VisitCastExpr(CastExpr *CE) {
1950 Expr *E = CE->getSubExpr();
1951 QualType DestTy = CE->getType();
1952 CastKind Kind = CE->getCastKind();
1954 // These cases are generally not written to ignore the result of
1955 // evaluating their sub-expressions, so we clear this now.
1956 bool Ignored = TestAndClearIgnoreResultAssign();
1958 // Since almost all cast kinds apply to scalars, this switch doesn't have
1959 // a default case, so the compiler will warn on a missing case. The cases
1960 // are in the same order as in the CastKind enum.
1962 case CK_Dependent: llvm_unreachable("dependent cast kind in IR gen!");
1963 case CK_BuiltinFnToFnPtr:
1964 llvm_unreachable("builtin functions are handled elsewhere");
1966 case CK_LValueBitCast:
1967 case CK_ObjCObjectLValueCast: {
1968 Address Addr = EmitLValue(E).getAddress();
1969 Addr = Builder.CreateElementBitCast(Addr, CGF.ConvertTypeForMem(DestTy));
1970 LValue LV = CGF.MakeAddrLValue(Addr, DestTy);
1971 return EmitLoadOfLValue(LV, CE->getExprLoc());
1974 case CK_LValueToRValueBitCast: {
1975 LValue SourceLVal = CGF.EmitLValue(E);
1976 Address Addr = Builder.CreateElementBitCast(SourceLVal.getAddress(),
1977 CGF.ConvertTypeForMem(DestTy));
1978 LValue DestLV = CGF.MakeAddrLValue(Addr, DestTy);
1979 DestLV.setTBAAInfo(TBAAAccessInfo::getMayAliasInfo());
1980 return EmitLoadOfLValue(DestLV, CE->getExprLoc());
1983 case CK_CPointerToObjCPointerCast:
1984 case CK_BlockPointerToObjCPointerCast:
1985 case CK_AnyPointerToBlockPointerCast:
1987 Value *Src = Visit(const_cast<Expr*>(E));
1988 llvm::Type *SrcTy = Src->getType();
1989 llvm::Type *DstTy = ConvertType(DestTy);
1990 if (SrcTy->isPtrOrPtrVectorTy() && DstTy->isPtrOrPtrVectorTy() &&
1991 SrcTy->getPointerAddressSpace() != DstTy->getPointerAddressSpace()) {
1992 llvm_unreachable("wrong cast for pointers in different address spaces"
1993 "(must be an address space cast)!");
1996 if (CGF.SanOpts.has(SanitizerKind::CFIUnrelatedCast)) {
1997 if (auto PT = DestTy->getAs<PointerType>())
1998 CGF.EmitVTablePtrCheckForCast(PT->getPointeeType(), Src,
2000 CodeGenFunction::CFITCK_UnrelatedCast,
2004 if (CGF.CGM.getCodeGenOpts().StrictVTablePointers) {
2005 const QualType SrcType = E->getType();
2007 if (SrcType.mayBeNotDynamicClass() && DestTy.mayBeDynamicClass()) {
2008 // Casting to pointer that could carry dynamic information (provided by
2009 // invariant.group) requires launder.
2010 Src = Builder.CreateLaunderInvariantGroup(Src);
2011 } else if (SrcType.mayBeDynamicClass() && DestTy.mayBeNotDynamicClass()) {
2012 // Casting to pointer that does not carry dynamic information (provided
2013 // by invariant.group) requires stripping it. Note that we don't do it
2014 // if the source could not be dynamic type and destination could be
2015 // dynamic because dynamic information is already laundered. It is
2016 // because launder(strip(src)) == launder(src), so there is no need to
2017 // add extra strip before launder.
2018 Src = Builder.CreateStripInvariantGroup(Src);
2022 // Update heapallocsite metadata when there is an explicit cast.
2023 if (llvm::CallInst *CI = dyn_cast<llvm::CallInst>(Src))
2024 if (CI->getMetadata("heapallocsite") && isa<ExplicitCastExpr>(CE))
2025 CGF.getDebugInfo()->
2026 addHeapAllocSiteMetadata(CI, CE->getType(), CE->getExprLoc());
2028 return Builder.CreateBitCast(Src, DstTy);
2030 case CK_AddressSpaceConversion: {
2031 Expr::EvalResult Result;
2032 if (E->EvaluateAsRValue(Result, CGF.getContext()) &&
2033 Result.Val.isNullPointer()) {
2034 // If E has side effect, it is emitted even if its final result is a
2035 // null pointer. In that case, a DCE pass should be able to
2036 // eliminate the useless instructions emitted during translating E.
2037 if (Result.HasSideEffects)
2039 return CGF.CGM.getNullPointer(cast<llvm::PointerType>(
2040 ConvertType(DestTy)), DestTy);
2042 // Since target may map different address spaces in AST to the same address
2043 // space, an address space conversion may end up as a bitcast.
2044 return CGF.CGM.getTargetCodeGenInfo().performAddrSpaceCast(
2045 CGF, Visit(E), E->getType()->getPointeeType().getAddressSpace(),
2046 DestTy->getPointeeType().getAddressSpace(), ConvertType(DestTy));
2048 case CK_AtomicToNonAtomic:
2049 case CK_NonAtomicToAtomic:
2051 case CK_UserDefinedConversion:
2052 return Visit(const_cast<Expr*>(E));
2054 case CK_BaseToDerived: {
2055 const CXXRecordDecl *DerivedClassDecl = DestTy->getPointeeCXXRecordDecl();
2056 assert(DerivedClassDecl && "BaseToDerived arg isn't a C++ object pointer!");
2058 Address Base = CGF.EmitPointerWithAlignment(E);
2060 CGF.GetAddressOfDerivedClass(Base, DerivedClassDecl,
2061 CE->path_begin(), CE->path_end(),
2062 CGF.ShouldNullCheckClassCastValue(CE));
2064 // C++11 [expr.static.cast]p11: Behavior is undefined if a downcast is
2065 // performed and the object is not of the derived type.
2066 if (CGF.sanitizePerformTypeCheck())
2067 CGF.EmitTypeCheck(CodeGenFunction::TCK_DowncastPointer, CE->getExprLoc(),
2068 Derived.getPointer(), DestTy->getPointeeType());
2070 if (CGF.SanOpts.has(SanitizerKind::CFIDerivedCast))
2071 CGF.EmitVTablePtrCheckForCast(
2072 DestTy->getPointeeType(), Derived.getPointer(),
2073 /*MayBeNull=*/true, CodeGenFunction::CFITCK_DerivedCast,
2076 return Derived.getPointer();
2078 case CK_UncheckedDerivedToBase:
2079 case CK_DerivedToBase: {
2080 // The EmitPointerWithAlignment path does this fine; just discard
2082 return CGF.EmitPointerWithAlignment(CE).getPointer();
2086 Address V = CGF.EmitPointerWithAlignment(E);
2087 const CXXDynamicCastExpr *DCE = cast<CXXDynamicCastExpr>(CE);
2088 return CGF.EmitDynamicCast(V, DCE);
2091 case CK_ArrayToPointerDecay:
2092 return CGF.EmitArrayToPointerDecay(E).getPointer();
2093 case CK_FunctionToPointerDecay:
2094 return EmitLValue(E).getPointer();
2096 case CK_NullToPointer:
2097 if (MustVisitNullValue(E))
2098 CGF.EmitIgnoredExpr(E);
2100 return CGF.CGM.getNullPointer(cast<llvm::PointerType>(ConvertType(DestTy)),
2103 case CK_NullToMemberPointer: {
2104 if (MustVisitNullValue(E))
2105 CGF.EmitIgnoredExpr(E);
2107 const MemberPointerType *MPT = CE->getType()->getAs<MemberPointerType>();
2108 return CGF.CGM.getCXXABI().EmitNullMemberPointer(MPT);
2111 case CK_ReinterpretMemberPointer:
2112 case CK_BaseToDerivedMemberPointer:
2113 case CK_DerivedToBaseMemberPointer: {
2114 Value *Src = Visit(E);
2116 // Note that the AST doesn't distinguish between checked and
2117 // unchecked member pointer conversions, so we always have to
2118 // implement checked conversions here. This is inefficient when
2119 // actual control flow may be required in order to perform the
2120 // check, which it is for data member pointers (but not member
2121 // function pointers on Itanium and ARM).
2122 return CGF.CGM.getCXXABI().EmitMemberPointerConversion(CGF, CE, Src);
2125 case CK_ARCProduceObject:
2126 return CGF.EmitARCRetainScalarExpr(E);
2127 case CK_ARCConsumeObject:
2128 return CGF.EmitObjCConsumeObject(E->getType(), Visit(E));
2129 case CK_ARCReclaimReturnedObject:
2130 return CGF.EmitARCReclaimReturnedObject(E, /*allowUnsafe*/ Ignored);
2131 case CK_ARCExtendBlockObject:
2132 return CGF.EmitARCExtendBlockObject(E);
2134 case CK_CopyAndAutoreleaseBlockObject:
2135 return CGF.EmitBlockCopyAndAutorelease(Visit(E), E->getType());
2137 case CK_FloatingRealToComplex:
2138 case CK_FloatingComplexCast:
2139 case CK_IntegralRealToComplex:
2140 case CK_IntegralComplexCast:
2141 case CK_IntegralComplexToFloatingComplex:
2142 case CK_FloatingComplexToIntegralComplex:
2143 case CK_ConstructorConversion:
2145 llvm_unreachable("scalar cast to non-scalar value");
2147 case CK_LValueToRValue:
2148 assert(CGF.getContext().hasSameUnqualifiedType(E->getType(), DestTy));
2149 assert(E->isGLValue() && "lvalue-to-rvalue applied to r-value!");
2150 return Visit(const_cast<Expr*>(E));
2152 case CK_IntegralToPointer: {
2153 Value *Src = Visit(const_cast<Expr*>(E));
2155 // First, convert to the correct width so that we control the kind of
2157 auto DestLLVMTy = ConvertType(DestTy);
2158 llvm::Type *MiddleTy = CGF.CGM.getDataLayout().getIntPtrType(DestLLVMTy);
2159 bool InputSigned = E->getType()->isSignedIntegerOrEnumerationType();
2160 llvm::Value* IntResult =
2161 Builder.CreateIntCast(Src, MiddleTy, InputSigned, "conv");
2163 auto *IntToPtr = Builder.CreateIntToPtr(IntResult, DestLLVMTy);
2165 if (CGF.CGM.getCodeGenOpts().StrictVTablePointers) {
2166 // Going from integer to pointer that could be dynamic requires reloading
2167 // dynamic information from invariant.group.
2168 if (DestTy.mayBeDynamicClass())
2169 IntToPtr = Builder.CreateLaunderInvariantGroup(IntToPtr);
2173 case CK_PointerToIntegral: {
2174 assert(!DestTy->isBooleanType() && "bool should use PointerToBool");
2175 auto *PtrExpr = Visit(E);
2177 if (CGF.CGM.getCodeGenOpts().StrictVTablePointers) {
2178 const QualType SrcType = E->getType();
2180 // Casting to integer requires stripping dynamic information as it does
2182 if (SrcType.mayBeDynamicClass())
2183 PtrExpr = Builder.CreateStripInvariantGroup(PtrExpr);
2186 return Builder.CreatePtrToInt(PtrExpr, ConvertType(DestTy));
2189 CGF.EmitIgnoredExpr(E);
2192 case CK_VectorSplat: {
2193 llvm::Type *DstTy = ConvertType(DestTy);
2194 Value *Elt = Visit(const_cast<Expr*>(E));
2195 // Splat the element across to all elements
2196 unsigned NumElements = DstTy->getVectorNumElements();
2197 return Builder.CreateVectorSplat(NumElements, Elt, "splat");
2200 case CK_FixedPointCast:
2201 return EmitScalarConversion(Visit(E), E->getType(), DestTy,
2204 case CK_FixedPointToBoolean:
2205 assert(E->getType()->isFixedPointType() &&
2206 "Expected src type to be fixed point type");
2207 assert(DestTy->isBooleanType() && "Expected dest type to be boolean type");
2208 return EmitScalarConversion(Visit(E), E->getType(), DestTy,
2211 case CK_FixedPointToIntegral:
2212 assert(E->getType()->isFixedPointType() &&
2213 "Expected src type to be fixed point type");
2214 assert(DestTy->isIntegerType() && "Expected dest type to be an integer");
2215 return EmitScalarConversion(Visit(E), E->getType(), DestTy,
2218 case CK_IntegralToFixedPoint:
2219 assert(E->getType()->isIntegerType() &&
2220 "Expected src type to be an integer");
2221 assert(DestTy->isFixedPointType() &&
2222 "Expected dest type to be fixed point type");
2223 return EmitScalarConversion(Visit(E), E->getType(), DestTy,
2226 case CK_IntegralCast: {
2227 ScalarConversionOpts Opts;
2228 if (auto *ICE = dyn_cast<ImplicitCastExpr>(CE)) {
2229 if (!ICE->isPartOfExplicitCast())
2230 Opts = ScalarConversionOpts(CGF.SanOpts);
2232 return EmitScalarConversion(Visit(E), E->getType(), DestTy,
2233 CE->getExprLoc(), Opts);
2235 case CK_IntegralToFloating:
2236 case CK_FloatingToIntegral:
2237 case CK_FloatingCast:
2238 return EmitScalarConversion(Visit(E), E->getType(), DestTy,
2240 case CK_BooleanToSignedIntegral: {
2241 ScalarConversionOpts Opts;
2242 Opts.TreatBooleanAsSigned = true;
2243 return EmitScalarConversion(Visit(E), E->getType(), DestTy,
2244 CE->getExprLoc(), Opts);
2246 case CK_IntegralToBoolean:
2247 return EmitIntToBoolConversion(Visit(E));
2248 case CK_PointerToBoolean:
2249 return EmitPointerToBoolConversion(Visit(E), E->getType());
2250 case CK_FloatingToBoolean:
2251 return EmitFloatToBoolConversion(Visit(E));
2252 case CK_MemberPointerToBoolean: {
2253 llvm::Value *MemPtr = Visit(E);
2254 const MemberPointerType *MPT = E->getType()->getAs<MemberPointerType>();
2255 return CGF.CGM.getCXXABI().EmitMemberPointerIsNotNull(CGF, MemPtr, MPT);
2258 case CK_FloatingComplexToReal:
2259 case CK_IntegralComplexToReal:
2260 return CGF.EmitComplexExpr(E, false, true).first;
2262 case CK_FloatingComplexToBoolean:
2263 case CK_IntegralComplexToBoolean: {
2264 CodeGenFunction::ComplexPairTy V = CGF.EmitComplexExpr(E);
2266 // TODO: kill this function off, inline appropriate case here
2267 return EmitComplexToScalarConversion(V, E->getType(), DestTy,
2271 case CK_ZeroToOCLOpaqueType: {
2272 assert((DestTy->isEventT() || DestTy->isQueueT() ||
2273 DestTy->isOCLIntelSubgroupAVCType()) &&
2274 "CK_ZeroToOCLEvent cast on non-event type");
2275 return llvm::Constant::getNullValue(ConvertType(DestTy));
2278 case CK_IntToOCLSampler:
2279 return CGF.CGM.createOpenCLIntToSamplerConversion(E, CGF);
2283 llvm_unreachable("unknown scalar cast");
2286 Value *ScalarExprEmitter::VisitStmtExpr(const StmtExpr *E) {
2287 CodeGenFunction::StmtExprEvaluation eval(CGF);
2288 Address RetAlloca = CGF.EmitCompoundStmt(*E->getSubStmt(),
2289 !E->getType()->isVoidType());
2290 if (!RetAlloca.isValid())
2292 return CGF.EmitLoadOfScalar(CGF.MakeAddrLValue(RetAlloca, E->getType()),
2296 Value *ScalarExprEmitter::VisitExprWithCleanups(ExprWithCleanups *E) {
2297 CGF.enterFullExpression(E);
2298 CodeGenFunction::RunCleanupsScope Scope(CGF);
2299 Value *V = Visit(E->getSubExpr());
2300 // Defend against dominance problems caused by jumps out of expression
2301 // evaluation through the shared cleanup block.
2302 Scope.ForceCleanup({&V});
2306 //===----------------------------------------------------------------------===//
2308 //===----------------------------------------------------------------------===//
2310 static BinOpInfo createBinOpInfoFromIncDec(const UnaryOperator *E,
2311 llvm::Value *InVal, bool IsInc) {
2314 BinOp.RHS = llvm::ConstantInt::get(InVal->getType(), 1, false);
2315 BinOp.Ty = E->getType();
2316 BinOp.Opcode = IsInc ? BO_Add : BO_Sub;
2317 // FIXME: once UnaryOperator carries FPFeatures, copy it here.
2322 llvm::Value *ScalarExprEmitter::EmitIncDecConsiderOverflowBehavior(
2323 const UnaryOperator *E, llvm::Value *InVal, bool IsInc) {
2324 llvm::Value *Amount =
2325 llvm::ConstantInt::get(InVal->getType(), IsInc ? 1 : -1, true);
2326 StringRef Name = IsInc ? "inc" : "dec";
2327 switch (CGF.getLangOpts().getSignedOverflowBehavior()) {
2328 case LangOptions::SOB_Defined:
2329 return Builder.CreateAdd(InVal, Amount, Name);
2330 case LangOptions::SOB_Undefined:
2331 if (!CGF.SanOpts.has(SanitizerKind::SignedIntegerOverflow))
2332 return Builder.CreateNSWAdd(InVal, Amount, Name);
2334 case LangOptions::SOB_Trapping:
2335 if (!E->canOverflow())
2336 return Builder.CreateNSWAdd(InVal, Amount, Name);
2337 return EmitOverflowCheckedBinOp(createBinOpInfoFromIncDec(E, InVal, IsInc));
2339 llvm_unreachable("Unknown SignedOverflowBehaviorTy");
2343 ScalarExprEmitter::EmitScalarPrePostIncDec(const UnaryOperator *E, LValue LV,
2344 bool isInc, bool isPre) {
2346 QualType type = E->getSubExpr()->getType();
2347 llvm::PHINode *atomicPHI = nullptr;
2351 int amount = (isInc ? 1 : -1);
2352 bool isSubtraction = !isInc;
2354 if (const AtomicType *atomicTy = type->getAs<AtomicType>()) {
2355 type = atomicTy->getValueType();
2356 if (isInc && type->isBooleanType()) {
2357 llvm::Value *True = CGF.EmitToMemory(Builder.getTrue(), type);
2359 Builder.CreateStore(True, LV.getAddress(), LV.isVolatileQualified())
2360 ->setAtomic(llvm::AtomicOrdering::SequentiallyConsistent);
2361 return Builder.getTrue();
2363 // For atomic bool increment, we just store true and return it for
2364 // preincrement, do an atomic swap with true for postincrement
2365 return Builder.CreateAtomicRMW(
2366 llvm::AtomicRMWInst::Xchg, LV.getPointer(), True,
2367 llvm::AtomicOrdering::SequentiallyConsistent);
2369 // Special case for atomic increment / decrement on integers, emit
2370 // atomicrmw instructions. We skip this if we want to be doing overflow
2371 // checking, and fall into the slow path with the atomic cmpxchg loop.
2372 if (!type->isBooleanType() && type->isIntegerType() &&
2373 !(type->isUnsignedIntegerType() &&
2374 CGF.SanOpts.has(SanitizerKind::UnsignedIntegerOverflow)) &&
2375 CGF.getLangOpts().getSignedOverflowBehavior() !=
2376 LangOptions::SOB_Trapping) {
2377 llvm::AtomicRMWInst::BinOp aop = isInc ? llvm::AtomicRMWInst::Add :
2378 llvm::AtomicRMWInst::Sub;
2379 llvm::Instruction::BinaryOps op = isInc ? llvm::Instruction::Add :
2380 llvm::Instruction::Sub;
2381 llvm::Value *amt = CGF.EmitToMemory(
2382 llvm::ConstantInt::get(ConvertType(type), 1, true), type);
2383 llvm::Value *old = Builder.CreateAtomicRMW(aop,
2384 LV.getPointer(), amt, llvm::AtomicOrdering::SequentiallyConsistent);
2385 return isPre ? Builder.CreateBinOp(op, old, amt) : old;
2387 value = EmitLoadOfLValue(LV, E->getExprLoc());
2389 // For every other atomic operation, we need to emit a load-op-cmpxchg loop
2390 llvm::BasicBlock *startBB = Builder.GetInsertBlock();
2391 llvm::BasicBlock *opBB = CGF.createBasicBlock("atomic_op", CGF.CurFn);
2392 value = CGF.EmitToMemory(value, type);
2393 Builder.CreateBr(opBB);
2394 Builder.SetInsertPoint(opBB);
2395 atomicPHI = Builder.CreatePHI(value->getType(), 2);
2396 atomicPHI->addIncoming(value, startBB);
2399 value = EmitLoadOfLValue(LV, E->getExprLoc());
2403 // Special case of integer increment that we have to check first: bool++.
2404 // Due to promotion rules, we get:
2405 // bool++ -> bool = bool + 1
2406 // -> bool = (int)bool + 1
2407 // -> bool = ((int)bool + 1 != 0)
2408 // An interesting aspect of this is that increment is always true.
2409 // Decrement does not have this property.
2410 if (isInc && type->isBooleanType()) {
2411 value = Builder.getTrue();
2413 // Most common case by far: integer increment.
2414 } else if (type->isIntegerType()) {
2415 // Note that signed integer inc/dec with width less than int can't
2416 // overflow because of promotion rules; we're just eliding a few steps here.
2417 if (E->canOverflow() && type->isSignedIntegerOrEnumerationType()) {
2418 value = EmitIncDecConsiderOverflowBehavior(E, value, isInc);
2419 } else if (E->canOverflow() && type->isUnsignedIntegerType() &&
2420 CGF.SanOpts.has(SanitizerKind::UnsignedIntegerOverflow)) {
2422 EmitOverflowCheckedBinOp(createBinOpInfoFromIncDec(E, value, isInc));
2424 llvm::Value *amt = llvm::ConstantInt::get(value->getType(), amount, true);
2425 value = Builder.CreateAdd(value, amt, isInc ? "inc" : "dec");
2428 // Next most common: pointer increment.
2429 } else if (const PointerType *ptr = type->getAs<PointerType>()) {
2430 QualType type = ptr->getPointeeType();
2432 // VLA types don't have constant size.
2433 if (const VariableArrayType *vla
2434 = CGF.getContext().getAsVariableArrayType(type)) {
2435 llvm::Value *numElts = CGF.getVLASize(vla).NumElts;
2436 if (!isInc) numElts = Builder.CreateNSWNeg(numElts, "vla.negsize");
2437 if (CGF.getLangOpts().isSignedOverflowDefined())
2438 value = Builder.CreateGEP(value, numElts, "vla.inc");
2440 value = CGF.EmitCheckedInBoundsGEP(
2441 value, numElts, /*SignedIndices=*/false, isSubtraction,
2442 E->getExprLoc(), "vla.inc");
2444 // Arithmetic on function pointers (!) is just +-1.
2445 } else if (type->isFunctionType()) {
2446 llvm::Value *amt = Builder.getInt32(amount);
2448 value = CGF.EmitCastToVoidPtr(value);
2449 if (CGF.getLangOpts().isSignedOverflowDefined())
2450 value = Builder.CreateGEP(value, amt, "incdec.funcptr");
2452 value = CGF.EmitCheckedInBoundsGEP(value, amt, /*SignedIndices=*/false,
2453 isSubtraction, E->getExprLoc(),
2455 value = Builder.CreateBitCast(value, input->getType());
2457 // For everything else, we can just do a simple increment.
2459 llvm::Value *amt = Builder.getInt32(amount);
2460 if (CGF.getLangOpts().isSignedOverflowDefined())
2461 value = Builder.CreateGEP(value, amt, "incdec.ptr");
2463 value = CGF.EmitCheckedInBoundsGEP(value, amt, /*SignedIndices=*/false,
2464 isSubtraction, E->getExprLoc(),
2468 // Vector increment/decrement.
2469 } else if (type->isVectorType()) {
2470 if (type->hasIntegerRepresentation()) {
2471 llvm::Value *amt = llvm::ConstantInt::get(value->getType(), amount);
2473 value = Builder.CreateAdd(value, amt, isInc ? "inc" : "dec");
2475 value = Builder.CreateFAdd(
2477 llvm::ConstantFP::get(value->getType(), amount),
2478 isInc ? "inc" : "dec");
2482 } else if (type->isRealFloatingType()) {
2483 // Add the inc/dec to the real part.
2486 if (type->isHalfType() && !CGF.getContext().getLangOpts().NativeHalfType) {
2487 // Another special case: half FP increment should be done via float
2488 if (CGF.getContext().getTargetInfo().useFP16ConversionIntrinsics()) {
2489 value = Builder.CreateCall(
2490 CGF.CGM.getIntrinsic(llvm::Intrinsic::convert_from_fp16,
2492 input, "incdec.conv");
2494 value = Builder.CreateFPExt(input, CGF.CGM.FloatTy, "incdec.conv");
2498 if (value->getType()->isFloatTy())
2499 amt = llvm::ConstantFP::get(VMContext,
2500 llvm::APFloat(static_cast<float>(amount)));
2501 else if (value->getType()->isDoubleTy())
2502 amt = llvm::ConstantFP::get(VMContext,
2503 llvm::APFloat(static_cast<double>(amount)));
2505 // Remaining types are Half, LongDouble or __float128. Convert from float.
2506 llvm::APFloat F(static_cast<float>(amount));
2508 const llvm::fltSemantics *FS;
2509 // Don't use getFloatTypeSemantics because Half isn't
2510 // necessarily represented using the "half" LLVM type.
2511 if (value->getType()->isFP128Ty())
2512 FS = &CGF.getTarget().getFloat128Format();
2513 else if (value->getType()->isHalfTy())
2514 FS = &CGF.getTarget().getHalfFormat();
2516 FS = &CGF.getTarget().getLongDoubleFormat();
2517 F.convert(*FS, llvm::APFloat::rmTowardZero, &ignored);
2518 amt = llvm::ConstantFP::get(VMContext, F);
2520 value = Builder.CreateFAdd(value, amt, isInc ? "inc" : "dec");
2522 if (type->isHalfType() && !CGF.getContext().getLangOpts().NativeHalfType) {
2523 if (CGF.getContext().getTargetInfo().useFP16ConversionIntrinsics()) {
2524 value = Builder.CreateCall(
2525 CGF.CGM.getIntrinsic(llvm::Intrinsic::convert_to_fp16,
2527 value, "incdec.conv");
2529 value = Builder.CreateFPTrunc(value, input->getType(), "incdec.conv");
2533 // Objective-C pointer types.
2535 const ObjCObjectPointerType *OPT = type->castAs<ObjCObjectPointerType>();
2536 value = CGF.EmitCastToVoidPtr(value);
2538 CharUnits size = CGF.getContext().getTypeSizeInChars(OPT->getObjectType());
2539 if (!isInc) size = -size;
2540 llvm::Value *sizeValue =
2541 llvm::ConstantInt::get(CGF.SizeTy, size.getQuantity());
2543 if (CGF.getLangOpts().isSignedOverflowDefined())
2544 value = Builder.CreateGEP(value, sizeValue, "incdec.objptr");
2546 value = CGF.EmitCheckedInBoundsGEP(value, sizeValue,
2547 /*SignedIndices=*/false, isSubtraction,
2548 E->getExprLoc(), "incdec.objptr");
2549 value = Builder.CreateBitCast(value, input->getType());
2553 llvm::BasicBlock *curBlock = Builder.GetInsertBlock();
2554 llvm::BasicBlock *contBB = CGF.createBasicBlock("atomic_cont", CGF.CurFn);
2555 auto Pair = CGF.EmitAtomicCompareExchange(
2556 LV, RValue::get(atomicPHI), RValue::get(value), E->getExprLoc());
2557 llvm::Value *old = CGF.EmitToMemory(Pair.first.getScalarVal(), type);
2558 llvm::Value *success = Pair.second;
2559 atomicPHI->addIncoming(old, curBlock);
2560 Builder.CreateCondBr(success, contBB, atomicPHI->getParent());
2561 Builder.SetInsertPoint(contBB);
2562 return isPre ? value : input;
2565 // Store the updated result through the lvalue.
2566 if (LV.isBitField())
2567 CGF.EmitStoreThroughBitfieldLValue(RValue::get(value), LV, &value);
2569 CGF.EmitStoreThroughLValue(RValue::get(value), LV);
2571 // If this is a postinc, return the value read from memory, otherwise use the
2573 return isPre ? value : input;
2578 Value *ScalarExprEmitter::VisitUnaryMinus(const UnaryOperator *E) {
2579 TestAndClearIgnoreResultAssign();
2580 // Emit unary minus with EmitSub so we handle overflow cases etc.
2582 BinOp.RHS = Visit(E->getSubExpr());
2584 if (BinOp.RHS->getType()->isFPOrFPVectorTy())
2585 BinOp.LHS = llvm::ConstantFP::getZeroValueForNegation(BinOp.RHS->getType());
2587 BinOp.LHS = llvm::Constant::getNullValue(BinOp.RHS->getType());
2588 BinOp.Ty = E->getType();
2589 BinOp.Opcode = BO_Sub;
2590 // FIXME: once UnaryOperator carries FPFeatures, copy it here.
2592 return EmitSub(BinOp);
2595 Value *ScalarExprEmitter::VisitUnaryNot(const UnaryOperator *E) {
2596 TestAndClearIgnoreResultAssign();
2597 Value *Op = Visit(E->getSubExpr());
2598 return Builder.CreateNot(Op, "neg");
2601 Value *ScalarExprEmitter::VisitUnaryLNot(const UnaryOperator *E) {
2602 // Perform vector logical not on comparison with zero vector.
2603 if (E->getType()->isExtVectorType()) {
2604 Value *Oper = Visit(E->getSubExpr());
2605 Value *Zero = llvm::Constant::getNullValue(Oper->getType());
2607 if (Oper->getType()->isFPOrFPVectorTy())
2608 Result = Builder.CreateFCmp(llvm::CmpInst::FCMP_OEQ, Oper, Zero, "cmp");
2610 Result = Builder.CreateICmp(llvm::CmpInst::ICMP_EQ, Oper, Zero, "cmp");
2611 return Builder.CreateSExt(Result, ConvertType(E->getType()), "sext");
2614 // Compare operand to zero.
2615 Value *BoolVal = CGF.EvaluateExprAsBool(E->getSubExpr());
2618 // TODO: Could dynamically modify easy computations here. For example, if
2619 // the operand is an icmp ne, turn into icmp eq.
2620 BoolVal = Builder.CreateNot(BoolVal, "lnot");
2622 // ZExt result to the expr type.
2623 return Builder.CreateZExt(BoolVal, ConvertType(E->getType()), "lnot.ext");
2626 Value *ScalarExprEmitter::VisitOffsetOfExpr(OffsetOfExpr *E) {
2627 // Try folding the offsetof to a constant.
2628 Expr::EvalResult EVResult;
2629 if (E->EvaluateAsInt(EVResult, CGF.getContext())) {
2630 llvm::APSInt Value = EVResult.Val.getInt();
2631 return Builder.getInt(Value);
2634 // Loop over the components of the offsetof to compute the value.
2635 unsigned n = E->getNumComponents();
2636 llvm::Type* ResultType = ConvertType(E->getType());
2637 llvm::Value* Result = llvm::Constant::getNullValue(ResultType);
2638 QualType CurrentType = E->getTypeSourceInfo()->getType();
2639 for (unsigned i = 0; i != n; ++i) {
2640 OffsetOfNode ON = E->getComponent(i);
2641 llvm::Value *Offset = nullptr;
2642 switch (ON.getKind()) {
2643 case OffsetOfNode::Array: {
2644 // Compute the index
2645 Expr *IdxExpr = E->getIndexExpr(ON.getArrayExprIndex());
2646 llvm::Value* Idx = CGF.EmitScalarExpr(IdxExpr);
2647 bool IdxSigned = IdxExpr->getType()->isSignedIntegerOrEnumerationType();
2648 Idx = Builder.CreateIntCast(Idx, ResultType, IdxSigned, "conv");
2650 // Save the element type
2652 CGF.getContext().getAsArrayType(CurrentType)->getElementType();
2654 // Compute the element size
2655 llvm::Value* ElemSize = llvm::ConstantInt::get(ResultType,
2656 CGF.getContext().getTypeSizeInChars(CurrentType).getQuantity());
2658 // Multiply out to compute the result
2659 Offset = Builder.CreateMul(Idx, ElemSize);
2663 case OffsetOfNode::Field: {
2664 FieldDecl *MemberDecl = ON.getField();
2665 RecordDecl *RD = CurrentType->getAs<RecordType>()->getDecl();
2666 const ASTRecordLayout &RL = CGF.getContext().getASTRecordLayout(RD);
2668 // Compute the index of the field in its parent.
2670 // FIXME: It would be nice if we didn't have to loop here!
2671 for (RecordDecl::field_iterator Field = RD->field_begin(),
2672 FieldEnd = RD->field_end();
2673 Field != FieldEnd; ++Field, ++i) {
2674 if (*Field == MemberDecl)
2677 assert(i < RL.getFieldCount() && "offsetof field in wrong type");
2679 // Compute the offset to the field
2680 int64_t OffsetInt = RL.getFieldOffset(i) /
2681 CGF.getContext().getCharWidth();
2682 Offset = llvm::ConstantInt::get(ResultType, OffsetInt);
2684 // Save the element type.
2685 CurrentType = MemberDecl->getType();
2689 case OffsetOfNode::Identifier:
2690 llvm_unreachable("dependent __builtin_offsetof");
2692 case OffsetOfNode::Base: {
2693 if (ON.getBase()->isVirtual()) {
2694 CGF.ErrorUnsupported(E, "virtual base in offsetof");
2698 RecordDecl *RD = CurrentType->getAs<RecordType>()->getDecl();
2699 const ASTRecordLayout &RL = CGF.getContext().getASTRecordLayout(RD);
2701 // Save the element type.
2702 CurrentType = ON.getBase()->getType();
2704 // Compute the offset to the base.
2705 const RecordType *BaseRT = CurrentType->getAs<RecordType>();
2706 CXXRecordDecl *BaseRD = cast<CXXRecordDecl>(BaseRT->getDecl());
2707 CharUnits OffsetInt = RL.getBaseClassOffset(BaseRD);
2708 Offset = llvm::ConstantInt::get(ResultType, OffsetInt.getQuantity());
2712 Result = Builder.CreateAdd(Result, Offset);
2717 /// VisitUnaryExprOrTypeTraitExpr - Return the size or alignment of the type of
2718 /// argument of the sizeof expression as an integer.
2720 ScalarExprEmitter::VisitUnaryExprOrTypeTraitExpr(
2721 const UnaryExprOrTypeTraitExpr *E) {
2722 QualType TypeToSize = E->getTypeOfArgument();
2723 if (E->getKind() == UETT_SizeOf) {
2724 if (const VariableArrayType *VAT =
2725 CGF.getContext().getAsVariableArrayType(TypeToSize)) {
2726 if (E->isArgumentType()) {
2727 // sizeof(type) - make sure to emit the VLA size.
2728 CGF.EmitVariablyModifiedType(TypeToSize);
2730 // C99 6.5.3.4p2: If the argument is an expression of type
2731 // VLA, it is evaluated.
2732 CGF.EmitIgnoredExpr(E->getArgumentExpr());
2735 auto VlaSize = CGF.getVLASize(VAT);
2736 llvm::Value *size = VlaSize.NumElts;
2738 // Scale the number of non-VLA elements by the non-VLA element size.
2739 CharUnits eltSize = CGF.getContext().getTypeSizeInChars(VlaSize.Type);
2740 if (!eltSize.isOne())
2741 size = CGF.Builder.CreateNUWMul(CGF.CGM.getSize(eltSize), size);
2745 } else if (E->getKind() == UETT_OpenMPRequiredSimdAlign) {
2748 .toCharUnitsFromBits(CGF.getContext().getOpenMPDefaultSimdAlign(
2749 E->getTypeOfArgument()->getPointeeType()))
2751 return llvm::ConstantInt::get(CGF.SizeTy, Alignment);
2754 // If this isn't sizeof(vla), the result must be constant; use the constant
2755 // folding logic so we don't have to duplicate it here.
2756 return Builder.getInt(E->EvaluateKnownConstInt(CGF.getContext()));
2759 Value *ScalarExprEmitter::VisitUnaryReal(const UnaryOperator *E) {
2760 Expr *Op = E->getSubExpr();
2761 if (Op->getType()->isAnyComplexType()) {
2762 // If it's an l-value, load through the appropriate subobject l-value.
2763 // Note that we have to ask E because Op might be an l-value that
2764 // this won't work for, e.g. an Obj-C property.
2766 return CGF.EmitLoadOfLValue(CGF.EmitLValue(E),
2767 E->getExprLoc()).getScalarVal();
2769 // Otherwise, calculate and project.
2770 return CGF.EmitComplexExpr(Op, false, true).first;
2776 Value *ScalarExprEmitter::VisitUnaryImag(const UnaryOperator *E) {
2777 Expr *Op = E->getSubExpr();
2778 if (Op->getType()->isAnyComplexType()) {
2779 // If it's an l-value, load through the appropriate subobject l-value.
2780 // Note that we have to ask E because Op might be an l-value that
2781 // this won't work for, e.g. an Obj-C property.
2782 if (Op->isGLValue())
2783 return CGF.EmitLoadOfLValue(CGF.EmitLValue(E),
2784 E->getExprLoc()).getScalarVal();
2786 // Otherwise, calculate and project.
2787 return CGF.EmitComplexExpr(Op, true, false).second;
2790 // __imag on a scalar returns zero. Emit the subexpr to ensure side
2791 // effects are evaluated, but not the actual value.
2792 if (Op->isGLValue())
2795 CGF.EmitScalarExpr(Op, true);
2796 return llvm::Constant::getNullValue(ConvertType(E->getType()));
2799 //===----------------------------------------------------------------------===//
2801 //===----------------------------------------------------------------------===//
2803 BinOpInfo ScalarExprEmitter::EmitBinOps(const BinaryOperator *E) {
2804 TestAndClearIgnoreResultAssign();
2806 Result.LHS = Visit(E->getLHS());
2807 Result.RHS = Visit(E->getRHS());
2808 Result.Ty = E->getType();
2809 Result.Opcode = E->getOpcode();
2810 Result.FPFeatures = E->getFPFeatures();
2815 LValue ScalarExprEmitter::EmitCompoundAssignLValue(
2816 const CompoundAssignOperator *E,
2817 Value *(ScalarExprEmitter::*Func)(const BinOpInfo &),
2819 QualType LHSTy = E->getLHS()->getType();
2822 if (E->getComputationResultType()->isAnyComplexType())
2823 return CGF.EmitScalarCompoundAssignWithComplex(E, Result);
2825 // Emit the RHS first. __block variables need to have the rhs evaluated
2826 // first, plus this should improve codegen a little.
2827 OpInfo.RHS = Visit(E->getRHS());
2828 OpInfo.Ty = E->getComputationResultType();
2829 OpInfo.Opcode = E->getOpcode();
2830 OpInfo.FPFeatures = E->getFPFeatures();
2832 // Load/convert the LHS.
2833 LValue LHSLV = EmitCheckedLValue(E->getLHS(), CodeGenFunction::TCK_Store);
2835 llvm::PHINode *atomicPHI = nullptr;
2836 if (const AtomicType *atomicTy = LHSTy->getAs<AtomicType>()) {
2837 QualType type = atomicTy->getValueType();
2838 if (!type->isBooleanType() && type->isIntegerType() &&
2839 !(type->isUnsignedIntegerType() &&
2840 CGF.SanOpts.has(SanitizerKind::UnsignedIntegerOverflow)) &&
2841 CGF.getLangOpts().getSignedOverflowBehavior() !=
2842 LangOptions::SOB_Trapping) {
2843 llvm::AtomicRMWInst::BinOp aop = llvm::AtomicRMWInst::BAD_BINOP;
2844 switch (OpInfo.Opcode) {
2845 // We don't have atomicrmw operands for *, %, /, <<, >>
2846 case BO_MulAssign: case BO_DivAssign:
2852 aop = llvm::AtomicRMWInst::Add;
2855 aop = llvm::AtomicRMWInst::Sub;
2858 aop = llvm::AtomicRMWInst::And;
2861 aop = llvm::AtomicRMWInst::Xor;
2864 aop = llvm::AtomicRMWInst::Or;
2867 llvm_unreachable("Invalid compound assignment type");
2869 if (aop != llvm::AtomicRMWInst::BAD_BINOP) {
2870 llvm::Value *amt = CGF.EmitToMemory(
2871 EmitScalarConversion(OpInfo.RHS, E->getRHS()->getType(), LHSTy,
2874 Builder.CreateAtomicRMW(aop, LHSLV.getPointer(), amt,
2875 llvm::AtomicOrdering::SequentiallyConsistent);
2879 // FIXME: For floating point types, we should be saving and restoring the
2880 // floating point environment in the loop.
2881 llvm::BasicBlock *startBB = Builder.GetInsertBlock();
2882 llvm::BasicBlock *opBB = CGF.createBasicBlock("atomic_op", CGF.CurFn);
2883 OpInfo.LHS = EmitLoadOfLValue(LHSLV, E->getExprLoc());
2884 OpInfo.LHS = CGF.EmitToMemory(OpInfo.LHS, type);
2885 Builder.CreateBr(opBB);
2886 Builder.SetInsertPoint(opBB);
2887 atomicPHI = Builder.CreatePHI(OpInfo.LHS->getType(), 2);
2888 atomicPHI->addIncoming(OpInfo.LHS, startBB);
2889 OpInfo.LHS = atomicPHI;
2892 OpInfo.LHS = EmitLoadOfLValue(LHSLV, E->getExprLoc());
2894 SourceLocation Loc = E->getExprLoc();
2896 EmitScalarConversion(OpInfo.LHS, LHSTy, E->getComputationLHSType(), Loc);
2898 // Expand the binary operator.
2899 Result = (this->*Func)(OpInfo);
2901 // Convert the result back to the LHS type,
2902 // potentially with Implicit Conversion sanitizer check.
2903 Result = EmitScalarConversion(Result, E->getComputationResultType(), LHSTy,
2904 Loc, ScalarConversionOpts(CGF.SanOpts));
2907 llvm::BasicBlock *curBlock = Builder.GetInsertBlock();
2908 llvm::BasicBlock *contBB = CGF.createBasicBlock("atomic_cont", CGF.CurFn);
2909 auto Pair = CGF.EmitAtomicCompareExchange(
2910 LHSLV, RValue::get(atomicPHI), RValue::get(Result), E->getExprLoc());
2911 llvm::Value *old = CGF.EmitToMemory(Pair.first.getScalarVal(), LHSTy);
2912 llvm::Value *success = Pair.second;
2913 atomicPHI->addIncoming(old, curBlock);
2914 Builder.CreateCondBr(success, contBB, atomicPHI->getParent());
2915 Builder.SetInsertPoint(contBB);
2919 // Store the result value into the LHS lvalue. Bit-fields are handled
2920 // specially because the result is altered by the store, i.e., [C99 6.5.16p1]
2921 // 'An assignment expression has the value of the left operand after the
2923 if (LHSLV.isBitField())
2924 CGF.EmitStoreThroughBitfieldLValue(RValue::get(Result), LHSLV, &Result);
2926 CGF.EmitStoreThroughLValue(RValue::get(Result), LHSLV);
2931 Value *ScalarExprEmitter::EmitCompoundAssign(const CompoundAssignOperator *E,
2932 Value *(ScalarExprEmitter::*Func)(const BinOpInfo &)) {
2933 bool Ignore = TestAndClearIgnoreResultAssign();
2934 Value *RHS = nullptr;
2935 LValue LHS = EmitCompoundAssignLValue(E, Func, RHS);
2937 // If the result is clearly ignored, return now.
2941 // The result of an assignment in C is the assigned r-value.
2942 if (!CGF.getLangOpts().CPlusPlus)
2945 // If the lvalue is non-volatile, return the computed value of the assignment.
2946 if (!LHS.isVolatileQualified())
2949 // Otherwise, reload the value.
2950 return EmitLoadOfLValue(LHS, E->getExprLoc());
2953 void ScalarExprEmitter::EmitUndefinedBehaviorIntegerDivAndRemCheck(
2954 const BinOpInfo &Ops, llvm::Value *Zero, bool isDiv) {
2955 SmallVector<std::pair<llvm::Value *, SanitizerMask>, 2> Checks;
2957 if (CGF.SanOpts.has(SanitizerKind::IntegerDivideByZero)) {
2958 Checks.push_back(std::make_pair(Builder.CreateICmpNE(Ops.RHS, Zero),
2959 SanitizerKind::IntegerDivideByZero));
2962 const auto *BO = cast<BinaryOperator>(Ops.E);
2963 if (CGF.SanOpts.has(SanitizerKind::SignedIntegerOverflow) &&
2964 Ops.Ty->hasSignedIntegerRepresentation() &&
2965 !IsWidenedIntegerOp(CGF.getContext(), BO->getLHS()) &&
2966 Ops.mayHaveIntegerOverflow()) {
2967 llvm::IntegerType *Ty = cast<llvm::IntegerType>(Zero->getType());
2969 llvm::Value *IntMin =
2970 Builder.getInt(llvm::APInt::getSignedMinValue(Ty->getBitWidth()));
2971 llvm::Value *NegOne = llvm::ConstantInt::get(Ty, -1ULL);
2973 llvm::Value *LHSCmp = Builder.CreateICmpNE(Ops.LHS, IntMin);
2974 llvm::Value *RHSCmp = Builder.CreateICmpNE(Ops.RHS, NegOne);
2975 llvm::Value *NotOverflow = Builder.CreateOr(LHSCmp, RHSCmp, "or");
2977 std::make_pair(NotOverflow, SanitizerKind::SignedIntegerOverflow));
2980 if (Checks.size() > 0)
2981 EmitBinOpCheck(Checks, Ops);
2984 Value *ScalarExprEmitter::EmitDiv(const BinOpInfo &Ops) {
2986 CodeGenFunction::SanitizerScope SanScope(&CGF);
2987 if ((CGF.SanOpts.has(SanitizerKind::IntegerDivideByZero) ||
2988 CGF.SanOpts.has(SanitizerKind::SignedIntegerOverflow)) &&
2989 Ops.Ty->isIntegerType() &&
2990 (Ops.mayHaveIntegerDivisionByZero() || Ops.mayHaveIntegerOverflow())) {
2991 llvm::Value *Zero = llvm::Constant::getNullValue(ConvertType(Ops.Ty));
2992 EmitUndefinedBehaviorIntegerDivAndRemCheck(Ops, Zero, true);
2993 } else if (CGF.SanOpts.has(SanitizerKind::FloatDivideByZero) &&
2994 Ops.Ty->isRealFloatingType() &&
2995 Ops.mayHaveFloatDivisionByZero()) {
2996 llvm::Value *Zero = llvm::Constant::getNullValue(ConvertType(Ops.Ty));
2997 llvm::Value *NonZero = Builder.CreateFCmpUNE(Ops.RHS, Zero);
2998 EmitBinOpCheck(std::make_pair(NonZero, SanitizerKind::FloatDivideByZero),
3003 if (Ops.LHS->getType()->isFPOrFPVectorTy()) {
3004 llvm::Value *Val = Builder.CreateFDiv(Ops.LHS, Ops.RHS, "div");
3005 if (CGF.getLangOpts().OpenCL &&
3006 !CGF.CGM.getCodeGenOpts().CorrectlyRoundedDivSqrt) {
3007 // OpenCL v1.1 s7.4: minimum accuracy of single precision / is 2.5ulp
3008 // OpenCL v1.2 s5.6.4.2: The -cl-fp32-correctly-rounded-divide-sqrt
3009 // build option allows an application to specify that single precision
3010 // floating-point divide (x/y and 1/x) and sqrt used in the program
3011 // source are correctly rounded.
3012 llvm::Type *ValTy = Val->getType();
3013 if (ValTy->isFloatTy() ||
3014 (isa<llvm::VectorType>(ValTy) &&
3015 cast<llvm::VectorType>(ValTy)->getElementType()->isFloatTy()))
3016 CGF.SetFPAccuracy(Val, 2.5);
3020 else if (Ops.Ty->hasUnsignedIntegerRepresentation())
3021 return Builder.CreateUDiv(Ops.LHS, Ops.RHS, "div");
3023 return Builder.CreateSDiv(Ops.LHS, Ops.RHS, "div");
3026 Value *ScalarExprEmitter::EmitRem(const BinOpInfo &Ops) {
3027 // Rem in C can't be a floating point type: C99 6.5.5p2.
3028 if ((CGF.SanOpts.has(SanitizerKind::IntegerDivideByZero) ||
3029 CGF.SanOpts.has(SanitizerKind::SignedIntegerOverflow)) &&
3030 Ops.Ty->isIntegerType() &&
3031 (Ops.mayHaveIntegerDivisionByZero() || Ops.mayHaveIntegerOverflow())) {
3032 CodeGenFunction::SanitizerScope SanScope(&CGF);
3033 llvm::Value *Zero = llvm::Constant::getNullValue(ConvertType(Ops.Ty));
3034 EmitUndefinedBehaviorIntegerDivAndRemCheck(Ops, Zero, false);
3037 if (Ops.Ty->hasUnsignedIntegerRepresentation())
3038 return Builder.CreateURem(Ops.LHS, Ops.RHS, "rem");
3040 return Builder.CreateSRem(Ops.LHS, Ops.RHS, "rem");
3043 Value *ScalarExprEmitter::EmitOverflowCheckedBinOp(const BinOpInfo &Ops) {
3047 bool isSigned = Ops.Ty->isSignedIntegerOrEnumerationType();
3048 switch (Ops.Opcode) {
3052 IID = isSigned ? llvm::Intrinsic::sadd_with_overflow :
3053 llvm::Intrinsic::uadd_with_overflow;
3058 IID = isSigned ? llvm::Intrinsic::ssub_with_overflow :
3059 llvm::Intrinsic::usub_with_overflow;
3064 IID = isSigned ? llvm::Intrinsic::smul_with_overflow :
3065 llvm::Intrinsic::umul_with_overflow;
3068 llvm_unreachable("Unsupported operation for overflow detection");
3074 CodeGenFunction::SanitizerScope SanScope(&CGF);
3075 llvm::Type *opTy = CGF.CGM.getTypes().ConvertType(Ops.Ty);
3077 llvm::Function *intrinsic = CGF.CGM.getIntrinsic(IID, opTy);
3079 Value *resultAndOverflow = Builder.CreateCall(intrinsic, {Ops.LHS, Ops.RHS});
3080 Value *result = Builder.CreateExtractValue(resultAndOverflow, 0);
3081 Value *overflow = Builder.CreateExtractValue(resultAndOverflow, 1);
3083 // Handle overflow with llvm.trap if no custom handler has been specified.
3084 const std::string *handlerName =
3085 &CGF.getLangOpts().OverflowHandler;
3086 if (handlerName->empty()) {
3087 // If the signed-integer-overflow sanitizer is enabled, emit a call to its
3088 // runtime. Otherwise, this is a -ftrapv check, so just emit a trap.
3089 if (!isSigned || CGF.SanOpts.has(SanitizerKind::SignedIntegerOverflow)) {
3090 llvm::Value *NotOverflow = Builder.CreateNot(overflow);
3091 SanitizerMask Kind = isSigned ? SanitizerKind::SignedIntegerOverflow
3092 : SanitizerKind::UnsignedIntegerOverflow;
3093 EmitBinOpCheck(std::make_pair(NotOverflow, Kind), Ops);
3095 CGF.EmitTrapCheck(Builder.CreateNot(overflow));
3099 // Branch in case of overflow.
3100 llvm::BasicBlock *initialBB = Builder.GetInsertBlock();
3101 llvm::BasicBlock *continueBB =
3102 CGF.createBasicBlock("nooverflow", CGF.CurFn, initialBB->getNextNode());
3103 llvm::BasicBlock *overflowBB = CGF.createBasicBlock("overflow", CGF.CurFn);
3105 Builder.CreateCondBr(overflow, overflowBB, continueBB);
3107 // If an overflow handler is set, then we want to call it and then use its
3108 // result, if it returns.
3109 Builder.SetInsertPoint(overflowBB);
3111 // Get the overflow handler.
3112 llvm::Type *Int8Ty = CGF.Int8Ty;
3113 llvm::Type *argTypes[] = { CGF.Int64Ty, CGF.Int64Ty, Int8Ty, Int8Ty };
3114 llvm::FunctionType *handlerTy =
3115 llvm::FunctionType::get(CGF.Int64Ty, argTypes, true);
3116 llvm::FunctionCallee handler =
3117 CGF.CGM.CreateRuntimeFunction(handlerTy, *handlerName);
3119 // Sign extend the args to 64-bit, so that we can use the same handler for
3120 // all types of overflow.
3121 llvm::Value *lhs = Builder.CreateSExt(Ops.LHS, CGF.Int64Ty);
3122 llvm::Value *rhs = Builder.CreateSExt(Ops.RHS, CGF.Int64Ty);
3124 // Call the handler with the two arguments, the operation, and the size of
3126 llvm::Value *handlerArgs[] = {
3129 Builder.getInt8(OpID),
3130 Builder.getInt8(cast<llvm::IntegerType>(opTy)->getBitWidth())
3132 llvm::Value *handlerResult =
3133 CGF.EmitNounwindRuntimeCall(handler, handlerArgs);
3135 // Truncate the result back to the desired size.
3136 handlerResult = Builder.CreateTrunc(handlerResult, opTy);
3137 Builder.CreateBr(continueBB);
3139 Builder.SetInsertPoint(continueBB);
3140 llvm::PHINode *phi = Builder.CreatePHI(opTy, 2);
3141 phi->addIncoming(result, initialBB);
3142 phi->addIncoming(handlerResult, overflowBB);
3147 /// Emit pointer + index arithmetic.
3148 static Value *emitPointerArithmetic(CodeGenFunction &CGF,
3149 const BinOpInfo &op,
3150 bool isSubtraction) {
3151 // Must have binary (not unary) expr here. Unary pointer
3152 // increment/decrement doesn't use this path.
3153 const BinaryOperator *expr = cast<BinaryOperator>(op.E);
3155 Value *pointer = op.LHS;
3156 Expr *pointerOperand = expr->getLHS();
3157 Value *index = op.RHS;
3158 Expr *indexOperand = expr->getRHS();
3160 // In a subtraction, the LHS is always the pointer.
3161 if (!isSubtraction && !pointer->getType()->isPointerTy()) {
3162 std::swap(pointer, index);
3163 std::swap(pointerOperand, indexOperand);
3166 bool isSigned = indexOperand->getType()->isSignedIntegerOrEnumerationType();
3168 unsigned width = cast<llvm::IntegerType>(index->getType())->getBitWidth();
3169 auto &DL = CGF.CGM.getDataLayout();
3170 auto PtrTy = cast<llvm::PointerType>(pointer->getType());
3172 // Some versions of glibc and gcc use idioms (particularly in their malloc
3173 // routines) that add a pointer-sized integer (known to be a pointer value)
3174 // to a null pointer in order to cast the value back to an integer or as
3175 // part of a pointer alignment algorithm. This is undefined behavior, but
3176 // we'd like to be able to compile programs that use it.
3178 // Normally, we'd generate a GEP with a null-pointer base here in response
3179 // to that code, but it's also UB to dereference a pointer created that
3180 // way. Instead (as an acknowledged hack to tolerate the idiom) we will
3181 // generate a direct cast of the integer value to a pointer.
3183 // The idiom (p = nullptr + N) is not met if any of the following are true:
3185 // The operation is subtraction.
3186 // The index is not pointer-sized.
3187 // The pointer type is not byte-sized.
3189 if (BinaryOperator::isNullPointerArithmeticExtension(CGF.getContext(),
3193 return CGF.Builder.CreateIntToPtr(index, pointer->getType());
3195 if (width != DL.getTypeSizeInBits(PtrTy)) {
3196 // Zero-extend or sign-extend the pointer value according to
3197 // whether the index is signed or not.
3198 index = CGF.Builder.CreateIntCast(index, DL.getIntPtrType(PtrTy), isSigned,
3202 // If this is subtraction, negate the index.
3204 index = CGF.Builder.CreateNeg(index, "idx.neg");
3206 if (CGF.SanOpts.has(SanitizerKind::ArrayBounds))
3207 CGF.EmitBoundsCheck(op.E, pointerOperand, index, indexOperand->getType(),
3208 /*Accessed*/ false);
3210 const PointerType *pointerType
3211 = pointerOperand->getType()->getAs<PointerType>();
3213 QualType objectType = pointerOperand->getType()
3214 ->castAs<ObjCObjectPointerType>()
3216 llvm::Value *objectSize
3217 = CGF.CGM.getSize(CGF.getContext().getTypeSizeInChars(objectType));
3219 index = CGF.Builder.CreateMul(index, objectSize);
3221 Value *result = CGF.Builder.CreateBitCast(pointer, CGF.VoidPtrTy);
3222 result = CGF.Builder.CreateGEP(result, index, "add.ptr");
3223 return CGF.Builder.CreateBitCast(result, pointer->getType());
3226 QualType elementType = pointerType->getPointeeType();
3227 if (const VariableArrayType *vla
3228 = CGF.getContext().getAsVariableArrayType(elementType)) {
3229 // The element count here is the total number of non-VLA elements.
3230 llvm::Value *numElements = CGF.getVLASize(vla).NumElts;
3232 // Effectively, the multiply by the VLA size is part of the GEP.
3233 // GEP indexes are signed, and scaling an index isn't permitted to
3234 // signed-overflow, so we use the same semantics for our explicit
3235 // multiply. We suppress this if overflow is not undefined behavior.
3236 if (CGF.getLangOpts().isSignedOverflowDefined()) {
3237 index = CGF.Builder.CreateMul(index, numElements, "vla.index");
3238 pointer = CGF.Builder.CreateGEP(pointer, index, "add.ptr");
3240 index = CGF.Builder.CreateNSWMul(index, numElements, "vla.index");
3242 CGF.EmitCheckedInBoundsGEP(pointer, index, isSigned, isSubtraction,
3243 op.E->getExprLoc(), "add.ptr");
3248 // Explicitly handle GNU void* and function pointer arithmetic extensions. The
3249 // GNU void* casts amount to no-ops since our void* type is i8*, but this is
3251 if (elementType->isVoidType() || elementType->isFunctionType()) {
3252 Value *result = CGF.Builder.CreateBitCast(pointer, CGF.VoidPtrTy);
3253 result = CGF.Builder.CreateGEP(result, index, "add.ptr");
3254 return CGF.Builder.CreateBitCast(result, pointer->getType());
3257 if (CGF.getLangOpts().isSignedOverflowDefined())
3258 return CGF.Builder.CreateGEP(pointer, index, "add.ptr");
3260 return CGF.EmitCheckedInBoundsGEP(pointer, index, isSigned, isSubtraction,
3261 op.E->getExprLoc(), "add.ptr");
3264 // Construct an fmuladd intrinsic to represent a fused mul-add of MulOp and
3265 // Addend. Use negMul and negAdd to negate the first operand of the Mul or
3266 // the add operand respectively. This allows fmuladd to represent a*b-c, or
3267 // c-a*b. Patterns in LLVM should catch the negated forms and translate them to
3268 // efficient operations.
3269 static Value* buildFMulAdd(llvm::BinaryOperator *MulOp, Value *Addend,
3270 const CodeGenFunction &CGF, CGBuilderTy &Builder,
3271 bool negMul, bool negAdd) {
3272 assert(!(negMul && negAdd) && "Only one of negMul and negAdd should be set.");
3274 Value *MulOp0 = MulOp->getOperand(0);
3275 Value *MulOp1 = MulOp->getOperand(1);
3279 llvm::ConstantFP::getZeroValueForNegation(MulOp0->getType()), MulOp0,
3281 } else if (negAdd) {
3284 llvm::ConstantFP::getZeroValueForNegation(Addend->getType()), Addend,
3288 Value *FMulAdd = Builder.CreateCall(
3289 CGF.CGM.getIntrinsic(llvm::Intrinsic::fmuladd, Addend->getType()),
3290 {MulOp0, MulOp1, Addend});
3291 MulOp->eraseFromParent();
3296 // Check whether it would be legal to emit an fmuladd intrinsic call to
3297 // represent op and if so, build the fmuladd.
3299 // Checks that (a) the operation is fusable, and (b) -ffp-contract=on.
3300 // Does NOT check the type of the operation - it's assumed that this function
3301 // will be called from contexts where it's known that the type is contractable.
3302 static Value* tryEmitFMulAdd(const BinOpInfo &op,
3303 const CodeGenFunction &CGF, CGBuilderTy &Builder,
3306 assert((op.Opcode == BO_Add || op.Opcode == BO_AddAssign ||
3307 op.Opcode == BO_Sub || op.Opcode == BO_SubAssign) &&
3308 "Only fadd/fsub can be the root of an fmuladd.");
3310 // Check whether this op is marked as fusable.
3311 if (!op.FPFeatures.allowFPContractWithinStatement())
3314 // We have a potentially fusable op. Look for a mul on one of the operands.
3315 // Also, make sure that the mul result isn't used directly. In that case,
3316 // there's no point creating a muladd operation.
3317 if (auto *LHSBinOp = dyn_cast<llvm::BinaryOperator>(op.LHS)) {
3318 if (LHSBinOp->getOpcode() == llvm::Instruction::FMul &&
3319 LHSBinOp->use_empty())
3320 return buildFMulAdd(LHSBinOp, op.RHS, CGF, Builder, false, isSub);
3322 if (auto *RHSBinOp = dyn_cast<llvm::BinaryOperator>(op.RHS)) {
3323 if (RHSBinOp->getOpcode() == llvm::Instruction::FMul &&
3324 RHSBinOp->use_empty())
3325 return buildFMulAdd(RHSBinOp, op.LHS, CGF, Builder, isSub, false);
3331 Value *ScalarExprEmitter::EmitAdd(const BinOpInfo &op) {
3332 if (op.LHS->getType()->isPointerTy() ||
3333 op.RHS->getType()->isPointerTy())
3334 return emitPointerArithmetic(CGF, op, CodeGenFunction::NotSubtraction);
3336 if (op.Ty->isSignedIntegerOrEnumerationType()) {
3337 switch (CGF.getLangOpts().getSignedOverflowBehavior()) {
3338 case LangOptions::SOB_Defined:
3339 return Builder.CreateAdd(op.LHS, op.RHS, "add");
3340 case LangOptions::SOB_Undefined:
3341 if (!CGF.SanOpts.has(SanitizerKind::SignedIntegerOverflow))
3342 return Builder.CreateNSWAdd(op.LHS, op.RHS, "add");
3344 case LangOptions::SOB_Trapping:
3345 if (CanElideOverflowCheck(CGF.getContext(), op))
3346 return Builder.CreateNSWAdd(op.LHS, op.RHS, "add");
3347 return EmitOverflowCheckedBinOp(op);
3351 if (op.Ty->isUnsignedIntegerType() &&
3352 CGF.SanOpts.has(SanitizerKind::UnsignedIntegerOverflow) &&
3353 !CanElideOverflowCheck(CGF.getContext(), op))
3354 return EmitOverflowCheckedBinOp(op);
3356 if (op.LHS->getType()->isFPOrFPVectorTy()) {
3357 // Try to form an fmuladd.
3358 if (Value *FMulAdd = tryEmitFMulAdd(op, CGF, Builder))
3361 Value *V = Builder.CreateFAdd(op.LHS, op.RHS, "add");
3362 return propagateFMFlags(V, op);
3365 if (op.isFixedPointBinOp())
3366 return EmitFixedPointBinOp(op);
3368 return Builder.CreateAdd(op.LHS, op.RHS, "add");
3371 /// The resulting value must be calculated with exact precision, so the operands
3372 /// may not be the same type.
3373 Value *ScalarExprEmitter::EmitFixedPointBinOp(const BinOpInfo &op) {
3375 using llvm::ConstantInt;
3377 const auto *BinOp = cast<BinaryOperator>(op.E);
3379 // The result is a fixed point type and at least one of the operands is fixed
3380 // point while the other is either fixed point or an int. This resulting type
3381 // should be determined by Sema::handleFixedPointConversions().
3382 QualType ResultTy = op.Ty;
3383 QualType LHSTy = BinOp->getLHS()->getType();
3384 QualType RHSTy = BinOp->getRHS()->getType();
3385 ASTContext &Ctx = CGF.getContext();
3386 Value *LHS = op.LHS;
3387 Value *RHS = op.RHS;
3389 auto LHSFixedSema = Ctx.getFixedPointSemantics(LHSTy);
3390 auto RHSFixedSema = Ctx.getFixedPointSemantics(RHSTy);
3391 auto ResultFixedSema = Ctx.getFixedPointSemantics(ResultTy);
3392 auto CommonFixedSema = LHSFixedSema.getCommonSemantics(RHSFixedSema);
3394 // Convert the operands to the full precision type.
3395 Value *FullLHS = EmitFixedPointConversion(LHS, LHSFixedSema, CommonFixedSema,
3396 BinOp->getExprLoc());
3397 Value *FullRHS = EmitFixedPointConversion(RHS, RHSFixedSema, CommonFixedSema,
3398 BinOp->getExprLoc());
3400 // Perform the actual addition.
3402 switch (BinOp->getOpcode()) {
3404 if (ResultFixedSema.isSaturated()) {
3405 llvm::Intrinsic::ID IID = ResultFixedSema.isSigned()
3406 ? llvm::Intrinsic::sadd_sat
3407 : llvm::Intrinsic::uadd_sat;
3408 Result = Builder.CreateBinaryIntrinsic(IID, FullLHS, FullRHS);
3410 Result = Builder.CreateAdd(FullLHS, FullRHS);
3415 if (ResultFixedSema.isSaturated()) {
3416 llvm::Intrinsic::ID IID = ResultFixedSema.isSigned()
3417 ? llvm::Intrinsic::ssub_sat
3418 : llvm::Intrinsic::usub_sat;
3419 Result = Builder.CreateBinaryIntrinsic(IID, FullLHS, FullRHS);
3421 Result = Builder.CreateSub(FullLHS, FullRHS);
3426 return CommonFixedSema.isSigned() ? Builder.CreateICmpSLT(FullLHS, FullRHS)
3427 : Builder.CreateICmpULT(FullLHS, FullRHS);
3429 return CommonFixedSema.isSigned() ? Builder.CreateICmpSGT(FullLHS, FullRHS)
3430 : Builder.CreateICmpUGT(FullLHS, FullRHS);
3432 return CommonFixedSema.isSigned() ? Builder.CreateICmpSLE(FullLHS, FullRHS)
3433 : Builder.CreateICmpULE(FullLHS, FullRHS);
3435 return CommonFixedSema.isSigned() ? Builder.CreateICmpSGE(FullLHS, FullRHS)
3436 : Builder.CreateICmpUGE(FullLHS, FullRHS);
3438 // For equality operations, we assume any padding bits on unsigned types are
3439 // zero'd out. They could be overwritten through non-saturating operations
3440 // that cause overflow, but this leads to undefined behavior.
3441 return Builder.CreateICmpEQ(FullLHS, FullRHS);
3443 return Builder.CreateICmpNE(FullLHS, FullRHS);
3457 llvm_unreachable("Found unimplemented fixed point binary operation");
3470 llvm_unreachable("Found unsupported binary operation for fixed point types.");
3473 // Convert to the result type.
3474 return EmitFixedPointConversion(Result, CommonFixedSema, ResultFixedSema,
3475 BinOp->getExprLoc());
3478 Value *ScalarExprEmitter::EmitSub(const BinOpInfo &op) {
3479 // The LHS is always a pointer if either side is.
3480 if (!op.LHS->getType()->isPointerTy()) {
3481 if (op.Ty->isSignedIntegerOrEnumerationType()) {
3482 switch (CGF.getLangOpts().getSignedOverflowBehavior()) {
3483 case LangOptions::SOB_Defined:
3484 return Builder.CreateSub(op.LHS, op.RHS, "sub");
3485 case LangOptions::SOB_Undefined:
3486 if (!CGF.SanOpts.has(SanitizerKind::SignedIntegerOverflow))
3487 return Builder.CreateNSWSub(op.LHS, op.RHS, "sub");
3489 case LangOptions::SOB_Trapping:
3490 if (CanElideOverflowCheck(CGF.getContext(), op))
3491 return Builder.CreateNSWSub(op.LHS, op.RHS, "sub");
3492 return EmitOverflowCheckedBinOp(op);
3496 if (op.Ty->isUnsignedIntegerType() &&
3497 CGF.SanOpts.has(SanitizerKind::UnsignedIntegerOverflow) &&
3498 !CanElideOverflowCheck(CGF.getContext(), op))
3499 return EmitOverflowCheckedBinOp(op);
3501 if (op.LHS->getType()->isFPOrFPVectorTy()) {
3502 // Try to form an fmuladd.
3503 if (Value *FMulAdd = tryEmitFMulAdd(op, CGF, Builder, true))
3505 Value *V = Builder.CreateFSub(op.LHS, op.RHS, "sub");
3506 return propagateFMFlags(V, op);
3509 if (op.isFixedPointBinOp())
3510 return EmitFixedPointBinOp(op);
3512 return Builder.CreateSub(op.LHS, op.RHS, "sub");
3515 // If the RHS is not a pointer, then we have normal pointer
3517 if (!op.RHS->getType()->isPointerTy())
3518 return emitPointerArithmetic(CGF, op, CodeGenFunction::IsSubtraction);
3520 // Otherwise, this is a pointer subtraction.
3522 // Do the raw subtraction part.
3524 = Builder.CreatePtrToInt(op.LHS, CGF.PtrDiffTy, "sub.ptr.lhs.cast");
3526 = Builder.CreatePtrToInt(op.RHS, CGF.PtrDiffTy, "sub.ptr.rhs.cast");
3527 Value *diffInChars = Builder.CreateSub(LHS, RHS, "sub.ptr.sub");
3529 // Okay, figure out the element size.
3530 const BinaryOperator *expr = cast<BinaryOperator>(op.E);
3531 QualType elementType = expr->getLHS()->getType()->getPointeeType();
3533 llvm::Value *divisor = nullptr;
3535 // For a variable-length array, this is going to be non-constant.
3536 if (const VariableArrayType *vla
3537 = CGF.getContext().getAsVariableArrayType(elementType)) {
3538 auto VlaSize = CGF.getVLASize(vla);
3539 elementType = VlaSize.Type;
3540 divisor = VlaSize.NumElts;
3542 // Scale the number of non-VLA elements by the non-VLA element size.
3543 CharUnits eltSize = CGF.getContext().getTypeSizeInChars(elementType);
3544 if (!eltSize.isOne())
3545 divisor = CGF.Builder.CreateNUWMul(CGF.CGM.getSize(eltSize), divisor);
3547 // For everything elese, we can just compute it, safe in the
3548 // assumption that Sema won't let anything through that we can't
3549 // safely compute the size of.
3551 CharUnits elementSize;
3552 // Handle GCC extension for pointer arithmetic on void* and
3553 // function pointer types.
3554 if (elementType->isVoidType() || elementType->isFunctionType())
3555 elementSize = CharUnits::One();
3557 elementSize = CGF.getContext().getTypeSizeInChars(elementType);
3559 // Don't even emit the divide for element size of 1.
3560 if (elementSize.isOne())
3563 divisor = CGF.CGM.getSize(elementSize);
3566 // Otherwise, do a full sdiv. This uses the "exact" form of sdiv, since
3567 // pointer difference in C is only defined in the case where both operands
3568 // are pointing to elements of an array.
3569 return Builder.CreateExactSDiv(diffInChars, divisor, "sub.ptr.div");
3572 Value *ScalarExprEmitter::GetWidthMinusOneValue(Value* LHS,Value* RHS) {
3573 llvm::IntegerType *Ty;
3574 if (llvm::VectorType *VT = dyn_cast<llvm::VectorType>(LHS->getType()))
3575 Ty = cast<llvm::IntegerType>(VT->getElementType());
3577 Ty = cast<llvm::IntegerType>(LHS->getType());
3578 return llvm::ConstantInt::get(RHS->getType(), Ty->getBitWidth() - 1);
3581 Value *ScalarExprEmitter::EmitShl(const BinOpInfo &Ops) {
3582 // LLVM requires the LHS and RHS to be the same type: promote or truncate the
3583 // RHS to the same size as the LHS.
3584 Value *RHS = Ops.RHS;
3585 if (Ops.LHS->getType() != RHS->getType())
3586 RHS = Builder.CreateIntCast(RHS, Ops.LHS->getType(), false, "sh_prom");
3588 bool SanitizeBase = CGF.SanOpts.has(SanitizerKind::ShiftBase) &&
3589 Ops.Ty->hasSignedIntegerRepresentation() &&
3590 !CGF.getLangOpts().isSignedOverflowDefined() &&
3591 !CGF.getLangOpts().CPlusPlus2a;
3592 bool SanitizeExponent = CGF.SanOpts.has(SanitizerKind::ShiftExponent);
3593 // OpenCL 6.3j: shift values are effectively % word size of LHS.
3594 if (CGF.getLangOpts().OpenCL)
3596 Builder.CreateAnd(RHS, GetWidthMinusOneValue(Ops.LHS, RHS), "shl.mask");
3597 else if ((SanitizeBase || SanitizeExponent) &&
3598 isa<llvm::IntegerType>(Ops.LHS->getType())) {
3599 CodeGenFunction::SanitizerScope SanScope(&CGF);
3600 SmallVector<std::pair<Value *, SanitizerMask>, 2> Checks;
3601 llvm::Value *WidthMinusOne = GetWidthMinusOneValue(Ops.LHS, Ops.RHS);
3602 llvm::Value *ValidExponent = Builder.CreateICmpULE(Ops.RHS, WidthMinusOne);
3604 if (SanitizeExponent) {
3606 std::make_pair(ValidExponent, SanitizerKind::ShiftExponent));
3610 // Check whether we are shifting any non-zero bits off the top of the
3611 // integer. We only emit this check if exponent is valid - otherwise
3612 // instructions below will have undefined behavior themselves.
3613 llvm::BasicBlock *Orig = Builder.GetInsertBlock();
3614 llvm::BasicBlock *Cont = CGF.createBasicBlock("cont");
3615 llvm::BasicBlock *CheckShiftBase = CGF.createBasicBlock("check");
3616 Builder.CreateCondBr(ValidExponent, CheckShiftBase, Cont);
3617 llvm::Value *PromotedWidthMinusOne =
3618 (RHS == Ops.RHS) ? WidthMinusOne
3619 : GetWidthMinusOneValue(Ops.LHS, RHS);
3620 CGF.EmitBlock(CheckShiftBase);
3621 llvm::Value *BitsShiftedOff = Builder.CreateLShr(
3622 Ops.LHS, Builder.CreateSub(PromotedWidthMinusOne, RHS, "shl.zeros",
3623 /*NUW*/ true, /*NSW*/ true),
3625 if (CGF.getLangOpts().CPlusPlus) {
3626 // In C99, we are not permitted to shift a 1 bit into the sign bit.
3627 // Under C++11's rules, shifting a 1 bit into the sign bit is
3628 // OK, but shifting a 1 bit out of it is not. (C89 and C++03 don't
3629 // define signed left shifts, so we use the C99 and C++11 rules there).
3630 llvm::Value *One = llvm::ConstantInt::get(BitsShiftedOff->getType(), 1);
3631 BitsShiftedOff = Builder.CreateLShr(BitsShiftedOff, One);
3633 llvm::Value *Zero = llvm::ConstantInt::get(BitsShiftedOff->getType(), 0);
3634 llvm::Value *ValidBase = Builder.CreateICmpEQ(BitsShiftedOff, Zero);
3635 CGF.EmitBlock(Cont);
3636 llvm::PHINode *BaseCheck = Builder.CreatePHI(ValidBase->getType(), 2);
3637 BaseCheck->addIncoming(Builder.getTrue(), Orig);
3638 BaseCheck->addIncoming(ValidBase, CheckShiftBase);
3639 Checks.push_back(std::make_pair(BaseCheck, SanitizerKind::ShiftBase));
3642 assert(!Checks.empty());
3643 EmitBinOpCheck(Checks, Ops);
3646 return Builder.CreateShl(Ops.LHS, RHS, "shl");
3649 Value *ScalarExprEmitter::EmitShr(const BinOpInfo &Ops) {
3650 // LLVM requires the LHS and RHS to be the same type: promote or truncate the
3651 // RHS to the same size as the LHS.
3652 Value *RHS = Ops.RHS;
3653 if (Ops.LHS->getType() != RHS->getType())
3654 RHS = Builder.CreateIntCast(RHS, Ops.LHS->getType(), false, "sh_prom");
3656 // OpenCL 6.3j: shift values are effectively % word size of LHS.
3657 if (CGF.getLangOpts().OpenCL)
3659 Builder.CreateAnd(RHS, GetWidthMinusOneValue(Ops.LHS, RHS), "shr.mask");
3660 else if (CGF.SanOpts.has(SanitizerKind::ShiftExponent) &&
3661 isa<llvm::IntegerType>(Ops.LHS->getType())) {
3662 CodeGenFunction::SanitizerScope SanScope(&CGF);
3663 llvm::Value *Valid =
3664 Builder.CreateICmpULE(RHS, GetWidthMinusOneValue(Ops.LHS, RHS));
3665 EmitBinOpCheck(std::make_pair(Valid, SanitizerKind::ShiftExponent), Ops);
3668 if (Ops.Ty->hasUnsignedIntegerRepresentation())
3669 return Builder.CreateLShr(Ops.LHS, RHS, "shr");
3670 return Builder.CreateAShr(Ops.LHS, RHS, "shr");
3673 enum IntrinsicType { VCMPEQ, VCMPGT };
3674 // return corresponding comparison intrinsic for given vector type
3675 static llvm::Intrinsic::ID GetIntrinsic(IntrinsicType IT,
3676 BuiltinType::Kind ElemKind) {
3678 default: llvm_unreachable("unexpected element type");
3679 case BuiltinType::Char_U:
3680 case BuiltinType::UChar:
3681 return (IT == VCMPEQ) ? llvm::Intrinsic::ppc_altivec_vcmpequb_p :
3682 llvm::Intrinsic::ppc_altivec_vcmpgtub_p;
3683 case BuiltinType::Char_S:
3684 case BuiltinType::SChar:
3685 return (IT == VCMPEQ) ? llvm::Intrinsic::ppc_altivec_vcmpequb_p :
3686 llvm::Intrinsic::ppc_altivec_vcmpgtsb_p;
3687 case BuiltinType::UShort:
3688 return (IT == VCMPEQ) ? llvm::Intrinsic::ppc_altivec_vcmpequh_p :
3689 llvm::Intrinsic::ppc_altivec_vcmpgtuh_p;
3690 case BuiltinType::Short:
3691 return (IT == VCMPEQ) ? llvm::Intrinsic::ppc_altivec_vcmpequh_p :
3692 llvm::Intrinsic::ppc_altivec_vcmpgtsh_p;
3693 case BuiltinType::UInt:
3694 return (IT == VCMPEQ) ? llvm::Intrinsic::ppc_altivec_vcmpequw_p :
3695 llvm::Intrinsic::ppc_altivec_vcmpgtuw_p;
3696 case BuiltinType::Int:
3697 return (IT == VCMPEQ) ? llvm::Intrinsic::ppc_altivec_vcmpequw_p :
3698 llvm::Intrinsic::ppc_altivec_vcmpgtsw_p;
3699 case BuiltinType::ULong:
3700 case BuiltinType::ULongLong:
3701 return (IT == VCMPEQ) ? llvm::Intrinsic::ppc_altivec_vcmpequd_p :
3702 llvm::Intrinsic::ppc_altivec_vcmpgtud_p;
3703 case BuiltinType::Long:
3704 case BuiltinType::LongLong:
3705 return (IT == VCMPEQ) ? llvm::Intrinsic::ppc_altivec_vcmpequd_p :
3706 llvm::Intrinsic::ppc_altivec_vcmpgtsd_p;
3707 case BuiltinType::Float:
3708 return (IT == VCMPEQ) ? llvm::Intrinsic::ppc_altivec_vcmpeqfp_p :
3709 llvm::Intrinsic::ppc_altivec_vcmpgtfp_p;
3710 case BuiltinType::Double:
3711 return (IT == VCMPEQ) ? llvm::Intrinsic::ppc_vsx_xvcmpeqdp_p :
3712 llvm::Intrinsic::ppc_vsx_xvcmpgtdp_p;
3716 Value *ScalarExprEmitter::EmitCompare(const BinaryOperator *E,
3717 llvm::CmpInst::Predicate UICmpOpc,
3718 llvm::CmpInst::Predicate SICmpOpc,
3719 llvm::CmpInst::Predicate FCmpOpc) {
3720 TestAndClearIgnoreResultAssign();
3722 QualType LHSTy = E->getLHS()->getType();
3723 QualType RHSTy = E->getRHS()->getType();
3724 if (const MemberPointerType *MPT = LHSTy->getAs<MemberPointerType>()) {
3725 assert(E->getOpcode() == BO_EQ ||
3726 E->getOpcode() == BO_NE);
3727 Value *LHS = CGF.EmitScalarExpr(E->getLHS());
3728 Value *RHS = CGF.EmitScalarExpr(E->getRHS());
3729 Result = CGF.CGM.getCXXABI().EmitMemberPointerComparison(
3730 CGF, LHS, RHS, MPT, E->getOpcode() == BO_NE);
3731 } else if (!LHSTy->isAnyComplexType() && !RHSTy->isAnyComplexType()) {
3732 BinOpInfo BOInfo = EmitBinOps(E);
3733 Value *LHS = BOInfo.LHS;
3734 Value *RHS = BOInfo.RHS;
3736 // If AltiVec, the comparison results in a numeric type, so we use
3737 // intrinsics comparing vectors and giving 0 or 1 as a result
3738 if (LHSTy->isVectorType() && !E->getType()->isVectorType()) {
3739 // constants for mapping CR6 register bits to predicate result
3740 enum { CR6_EQ=0, CR6_EQ_REV, CR6_LT, CR6_LT_REV } CR6;
3742 llvm::Intrinsic::ID ID = llvm::Intrinsic::not_intrinsic;
3744 // in several cases vector arguments order will be reversed
3745 Value *FirstVecArg = LHS,
3746 *SecondVecArg = RHS;
3748 QualType ElTy = LHSTy->getAs<VectorType>()->getElementType();
3749 const BuiltinType *BTy = ElTy->getAs<BuiltinType>();
3750 BuiltinType::Kind ElementKind = BTy->getKind();
3752 switch(E->getOpcode()) {
3753 default: llvm_unreachable("is not a comparison operation");
3756 ID = GetIntrinsic(VCMPEQ, ElementKind);
3760 ID = GetIntrinsic(VCMPEQ, ElementKind);
3764 ID = GetIntrinsic(VCMPGT, ElementKind);
3765 std::swap(FirstVecArg, SecondVecArg);
3769 ID = GetIntrinsic(VCMPGT, ElementKind);
3772 if (ElementKind == BuiltinType::Float) {
3774 ID = llvm::Intrinsic::ppc_altivec_vcmpgefp_p;
3775 std::swap(FirstVecArg, SecondVecArg);
3779 ID = GetIntrinsic(VCMPGT, ElementKind);
3783 if (ElementKind == BuiltinType::Float) {
3785 ID = llvm::Intrinsic::ppc_altivec_vcmpgefp_p;
3789 ID = GetIntrinsic(VCMPGT, ElementKind);
3790 std::swap(FirstVecArg, SecondVecArg);
3795 Value *CR6Param = Builder.getInt32(CR6);
3796 llvm::Function *F = CGF.CGM.getIntrinsic(ID);
3797 Result = Builder.CreateCall(F, {CR6Param, FirstVecArg, SecondVecArg});
3799 // The result type of intrinsic may not be same as E->getType().
3800 // If E->getType() is not BoolTy, EmitScalarConversion will do the
3801 // conversion work. If E->getType() is BoolTy, EmitScalarConversion will
3802 // do nothing, if ResultTy is not i1 at the same time, it will cause
3804 llvm::IntegerType *ResultTy = cast<llvm::IntegerType>(Result->getType());
3805 if (ResultTy->getBitWidth() > 1 &&
3806 E->getType() == CGF.getContext().BoolTy)
3807 Result = Builder.CreateTrunc(Result, Builder.getInt1Ty());
3808 return EmitScalarConversion(Result, CGF.getContext().BoolTy, E->getType(),
3812 if (BOInfo.isFixedPointBinOp()) {
3813 Result = EmitFixedPointBinOp(BOInfo);
3814 } else if (LHS->getType()->isFPOrFPVectorTy()) {
3815 Result = Builder.CreateFCmp(FCmpOpc, LHS, RHS, "cmp");
3816 } else if (LHSTy->hasSignedIntegerRepresentation()) {
3817 Result = Builder.CreateICmp(SICmpOpc, LHS, RHS, "cmp");
3819 // Unsigned integers and pointers.
3821 if (CGF.CGM.getCodeGenOpts().StrictVTablePointers &&
3822 !isa<llvm::ConstantPointerNull>(LHS) &&
3823 !isa<llvm::ConstantPointerNull>(RHS)) {
3825 // Dynamic information is required to be stripped for comparisons,
3826 // because it could leak the dynamic information. Based on comparisons
3827 // of pointers to dynamic objects, the optimizer can replace one pointer
3828 // with another, which might be incorrect in presence of invariant
3829 // groups. Comparison with null is safe because null does not carry any
3830 // dynamic information.
3831 if (LHSTy.mayBeDynamicClass())
3832 LHS = Builder.CreateStripInvariantGroup(LHS);
3833 if (RHSTy.mayBeDynamicClass())
3834 RHS = Builder.CreateStripInvariantGroup(RHS);
3837 Result = Builder.CreateICmp(UICmpOpc, LHS, RHS, "cmp");
3840 // If this is a vector comparison, sign extend the result to the appropriate
3841 // vector integer type and return it (don't convert to bool).
3842 if (LHSTy->isVectorType())
3843 return Builder.CreateSExt(Result, ConvertType(E->getType()), "sext");
3846 // Complex Comparison: can only be an equality comparison.
3847 CodeGenFunction::ComplexPairTy LHS, RHS;
3849 if (auto *CTy = LHSTy->getAs<ComplexType>()) {
3850 LHS = CGF.EmitComplexExpr(E->getLHS());
3851 CETy = CTy->getElementType();
3853 LHS.first = Visit(E->getLHS());
3854 LHS.second = llvm::Constant::getNullValue(LHS.first->getType());
3857 if (auto *CTy = RHSTy->getAs<ComplexType>()) {
3858 RHS = CGF.EmitComplexExpr(E->getRHS());
3859 assert(CGF.getContext().hasSameUnqualifiedType(CETy,
3860 CTy->getElementType()) &&
3861 "The element types must always match.");
3864 RHS.first = Visit(E->getRHS());
3865 RHS.second = llvm::Constant::getNullValue(RHS.first->getType());
3866 assert(CGF.getContext().hasSameUnqualifiedType(CETy, RHSTy) &&
3867 "The element types must always match.");
3870 Value *ResultR, *ResultI;
3871 if (CETy->isRealFloatingType()) {
3872 ResultR = Builder.CreateFCmp(FCmpOpc, LHS.first, RHS.first, "cmp.r");
3873 ResultI = Builder.CreateFCmp(FCmpOpc, LHS.second, RHS.second, "cmp.i");
3875 // Complex comparisons can only be equality comparisons. As such, signed
3876 // and unsigned opcodes are the same.
3877 ResultR = Builder.CreateICmp(UICmpOpc, LHS.first, RHS.first, "cmp.r");
3878 ResultI = Builder.CreateICmp(UICmpOpc, LHS.second, RHS.second, "cmp.i");
3881 if (E->getOpcode() == BO_EQ) {
3882 Result = Builder.CreateAnd(ResultR, ResultI, "and.ri");
3884 assert(E->getOpcode() == BO_NE &&
3885 "Complex comparison other than == or != ?");
3886 Result = Builder.CreateOr(ResultR, ResultI, "or.ri");
3890 return EmitScalarConversion(Result, CGF.getContext().BoolTy, E->getType(),
3894 Value *ScalarExprEmitter::VisitBinAssign(const BinaryOperator *E) {
3895 bool Ignore = TestAndClearIgnoreResultAssign();
3900 switch (E->getLHS()->getType().getObjCLifetime()) {
3901 case Qualifiers::OCL_Strong:
3902 std::tie(LHS, RHS) = CGF.EmitARCStoreStrong(E, Ignore);
3905 case Qualifiers::OCL_Autoreleasing:
3906 std::tie(LHS, RHS) = CGF.EmitARCStoreAutoreleasing(E);
3909 case Qualifiers::OCL_ExplicitNone:
3910 std::tie(LHS, RHS) = CGF.EmitARCStoreUnsafeUnretained(E, Ignore);
3913 case Qualifiers::OCL_Weak:
3914 RHS = Visit(E->getRHS());
3915 LHS = EmitCheckedLValue(E->getLHS(), CodeGenFunction::TCK_Store);
3916 RHS = CGF.EmitARCStoreWeak(LHS.getAddress(), RHS, Ignore);
3919 case Qualifiers::OCL_None:
3920 // __block variables need to have the rhs evaluated first, plus
3921 // this should improve codegen just a little.
3922 RHS = Visit(E->getRHS());
3923 LHS = EmitCheckedLValue(E->getLHS(), CodeGenFunction::TCK_Store);
3925 // Store the value into the LHS. Bit-fields are handled specially
3926 // because the result is altered by the store, i.e., [C99 6.5.16p1]
3927 // 'An assignment expression has the value of the left operand after
3928 // the assignment...'.
3929 if (LHS.isBitField()) {
3930 CGF.EmitStoreThroughBitfieldLValue(RValue::get(RHS), LHS, &RHS);
3932 CGF.EmitNullabilityCheck(LHS, RHS, E->getExprLoc());
3933 CGF.EmitStoreThroughLValue(RValue::get(RHS), LHS);
3937 // If the result is clearly ignored, return now.
3941 // The result of an assignment in C is the assigned r-value.
3942 if (!CGF.getLangOpts().CPlusPlus)
3945 // If the lvalue is non-volatile, return the computed value of the assignment.
3946 if (!LHS.isVolatileQualified())
3949 // Otherwise, reload the value.
3950 return EmitLoadOfLValue(LHS, E->getExprLoc());
3953 Value *ScalarExprEmitter::VisitBinLAnd(const BinaryOperator *E) {
3954 // Perform vector logical and on comparisons with zero vectors.
3955 if (E->getType()->isVectorType()) {
3956 CGF.incrementProfileCounter(E);
3958 Value *LHS = Visit(E->getLHS());
3959 Value *RHS = Visit(E->getRHS());
3960 Value *Zero = llvm::ConstantAggregateZero::get(LHS->getType());
3961 if (LHS->getType()->isFPOrFPVectorTy()) {
3962 LHS = Builder.CreateFCmp(llvm::CmpInst::FCMP_UNE, LHS, Zero, "cmp");
3963 RHS = Builder.CreateFCmp(llvm::CmpInst::FCMP_UNE, RHS, Zero, "cmp");
3965 LHS = Builder.CreateICmp(llvm::CmpInst::ICMP_NE, LHS, Zero, "cmp");
3966 RHS = Builder.CreateICmp(llvm::CmpInst::ICMP_NE, RHS, Zero, "cmp");
3968 Value *And = Builder.CreateAnd(LHS, RHS);
3969 return Builder.CreateSExt(And, ConvertType(E->getType()), "sext");
3972 llvm::Type *ResTy = ConvertType(E->getType());
3974 // If we have 0 && RHS, see if we can elide RHS, if so, just return 0.
3975 // If we have 1 && X, just emit X without inserting the control flow.
3977 if (CGF.ConstantFoldsToSimpleInteger(E->getLHS(), LHSCondVal)) {
3978 if (LHSCondVal) { // If we have 1 && X, just emit X.
3979 CGF.incrementProfileCounter(E);
3981 Value *RHSCond = CGF.EvaluateExprAsBool(E->getRHS());
3982 // ZExt result to int or bool.
3983 return Builder.CreateZExtOrBitCast(RHSCond, ResTy, "land.ext");
3986 // 0 && RHS: If it is safe, just elide the RHS, and return 0/false.
3987 if (!CGF.ContainsLabel(E->getRHS()))
3988 return llvm::Constant::getNullValue(ResTy);
3991 llvm::BasicBlock *ContBlock = CGF.createBasicBlock("land.end");
3992 llvm::BasicBlock *RHSBlock = CGF.createBasicBlock("land.rhs");
3994 CodeGenFunction::ConditionalEvaluation eval(CGF);
3996 // Branch on the LHS first. If it is false, go to the failure (cont) block.
3997 CGF.EmitBranchOnBoolExpr(E->getLHS(), RHSBlock, ContBlock,
3998 CGF.getProfileCount(E->getRHS()));
4000 // Any edges into the ContBlock are now from an (indeterminate number of)
4001 // edges from this first condition. All of these values will be false. Start
4002 // setting up the PHI node in the Cont Block for this.
4003 llvm::PHINode *PN = llvm::PHINode::Create(llvm::Type::getInt1Ty(VMContext), 2,
4005 for (llvm::pred_iterator PI = pred_begin(ContBlock), PE = pred_end(ContBlock);
4007 PN->addIncoming(llvm::ConstantInt::getFalse(VMContext), *PI);
4010 CGF.EmitBlock(RHSBlock);
4011 CGF.incrementProfileCounter(E);
4012 Value *RHSCond = CGF.EvaluateExprAsBool(E->getRHS());
4015 // Reaquire the RHS block, as there may be subblocks inserted.
4016 RHSBlock = Builder.GetInsertBlock();
4018 // Emit an unconditional branch from this block to ContBlock.
4020 // There is no need to emit line number for unconditional branch.
4021 auto NL = ApplyDebugLocation::CreateEmpty(CGF);
4022 CGF.EmitBlock(ContBlock);
4024 // Insert an entry into the phi node for the edge with the value of RHSCond.
4025 PN->addIncoming(RHSCond, RHSBlock);
4027 // Artificial location to preserve the scope information
4029 auto NL = ApplyDebugLocation::CreateArtificial(CGF);
4030 PN->setDebugLoc(Builder.getCurrentDebugLocation());
4033 // ZExt result to int.
4034 return Builder.CreateZExtOrBitCast(PN, ResTy, "land.ext");
4037 Value *ScalarExprEmitter::VisitBinLOr(const BinaryOperator *E) {
4038 // Perform vector logical or on comparisons with zero vectors.
4039 if (E->getType()->isVectorType()) {
4040 CGF.incrementProfileCounter(E);
4042 Value *LHS = Visit(E->getLHS());
4043 Value *RHS = Visit(E->getRHS());
4044 Value *Zero = llvm::ConstantAggregateZero::get(LHS->getType());
4045 if (LHS->getType()->isFPOrFPVectorTy()) {
4046 LHS = Builder.CreateFCmp(llvm::CmpInst::FCMP_UNE, LHS, Zero, "cmp");
4047 RHS = Builder.CreateFCmp(llvm::CmpInst::FCMP_UNE, RHS, Zero, "cmp");
4049 LHS = Builder.CreateICmp(llvm::CmpInst::ICMP_NE, LHS, Zero, "cmp");
4050 RHS = Builder.CreateICmp(llvm::CmpInst::ICMP_NE, RHS, Zero, "cmp");
4052 Value *Or = Builder.CreateOr(LHS, RHS);
4053 return Builder.CreateSExt(Or, ConvertType(E->getType()), "sext");
4056 llvm::Type *ResTy = ConvertType(E->getType());
4058 // If we have 1 || RHS, see if we can elide RHS, if so, just return 1.
4059 // If we have 0 || X, just emit X without inserting the control flow.
4061 if (CGF.ConstantFoldsToSimpleInteger(E->getLHS(), LHSCondVal)) {
4062 if (!LHSCondVal) { // If we have 0 || X, just emit X.
4063 CGF.incrementProfileCounter(E);
4065 Value *RHSCond = CGF.EvaluateExprAsBool(E->getRHS());
4066 // ZExt result to int or bool.
4067 return Builder.CreateZExtOrBitCast(RHSCond, ResTy, "lor.ext");
4070 // 1 || RHS: If it is safe, just elide the RHS, and return 1/true.
4071 if (!CGF.ContainsLabel(E->getRHS()))
4072 return llvm::ConstantInt::get(ResTy, 1);
4075 llvm::BasicBlock *ContBlock = CGF.createBasicBlock("lor.end");
4076 llvm::BasicBlock *RHSBlock = CGF.createBasicBlock("lor.rhs");
4078 CodeGenFunction::ConditionalEvaluation eval(CGF);
4080 // Branch on the LHS first. If it is true, go to the success (cont) block.
4081 CGF.EmitBranchOnBoolExpr(E->getLHS(), ContBlock, RHSBlock,
4082 CGF.getCurrentProfileCount() -
4083 CGF.getProfileCount(E->getRHS()));
4085 // Any edges into the ContBlock are now from an (indeterminate number of)
4086 // edges from this first condition. All of these values will be true. Start
4087 // setting up the PHI node in the Cont Block for this.
4088 llvm::PHINode *PN = llvm::PHINode::Create(llvm::Type::getInt1Ty(VMContext), 2,
4090 for (llvm::pred_iterator PI = pred_begin(ContBlock), PE = pred_end(ContBlock);
4092 PN->addIncoming(llvm::ConstantInt::getTrue(VMContext), *PI);
4096 // Emit the RHS condition as a bool value.
4097 CGF.EmitBlock(RHSBlock);
4098 CGF.incrementProfileCounter(E);
4099 Value *RHSCond = CGF.EvaluateExprAsBool(E->getRHS());
4103 // Reaquire the RHS block, as there may be subblocks inserted.
4104 RHSBlock = Builder.GetInsertBlock();
4106 // Emit an unconditional branch from this block to ContBlock. Insert an entry
4107 // into the phi node for the edge with the value of RHSCond.
4108 CGF.EmitBlock(ContBlock);
4109 PN->addIncoming(RHSCond, RHSBlock);
4111 // ZExt result to int.
4112 return Builder.CreateZExtOrBitCast(PN, ResTy, "lor.ext");
4115 Value *ScalarExprEmitter::VisitBinComma(const BinaryOperator *E) {
4116 CGF.EmitIgnoredExpr(E->getLHS());
4117 CGF.EnsureInsertPoint();
4118 return Visit(E->getRHS());
4121 //===----------------------------------------------------------------------===//
4123 //===----------------------------------------------------------------------===//
4125 /// isCheapEnoughToEvaluateUnconditionally - Return true if the specified
4126 /// expression is cheap enough and side-effect-free enough to evaluate
4127 /// unconditionally instead of conditionally. This is used to convert control
4128 /// flow into selects in some cases.
4129 static bool isCheapEnoughToEvaluateUnconditionally(const Expr *E,
4130 CodeGenFunction &CGF) {
4131 // Anything that is an integer or floating point constant is fine.
4132 return E->IgnoreParens()->isEvaluatable(CGF.getContext());
4134 // Even non-volatile automatic variables can't be evaluated unconditionally.
4135 // Referencing a thread_local may cause non-trivial initialization work to
4136 // occur. If we're inside a lambda and one of the variables is from the scope
4137 // outside the lambda, that function may have returned already. Reading its
4138 // locals is a bad idea. Also, these reads may introduce races there didn't
4139 // exist in the source-level program.
4143 Value *ScalarExprEmitter::
4144 VisitAbstractConditionalOperator(const AbstractConditionalOperator *E) {
4145 TestAndClearIgnoreResultAssign();
4147 // Bind the common expression if necessary.
4148 CodeGenFunction::OpaqueValueMapping binding(CGF, E);
4150 Expr *condExpr = E->getCond();
4151 Expr *lhsExpr = E->getTrueExpr();
4152 Expr *rhsExpr = E->getFalseExpr();
4154 // If the condition constant folds and can be elided, try to avoid emitting
4155 // the condition and the dead arm.
4157 if (CGF.ConstantFoldsToSimpleInteger(condExpr, CondExprBool)) {
4158 Expr *live = lhsExpr, *dead = rhsExpr;
4159 if (!CondExprBool) std::swap(live, dead);
4161 // If the dead side doesn't have labels we need, just emit the Live part.
4162 if (!CGF.ContainsLabel(dead)) {
4164 CGF.incrementProfileCounter(E);
4165 Value *Result = Visit(live);
4167 // If the live part is a throw expression, it acts like it has a void
4168 // type, so evaluating it returns a null Value*. However, a conditional
4169 // with non-void type must return a non-null Value*.
4170 if (!Result && !E->getType()->isVoidType())
4171 Result = llvm::UndefValue::get(CGF.ConvertType(E->getType()));
4177 // OpenCL: If the condition is a vector, we can treat this condition like
4178 // the select function.
4179 if (CGF.getLangOpts().OpenCL
4180 && condExpr->getType()->isVectorType()) {
4181 CGF.incrementProfileCounter(E);
4183 llvm::Value *CondV = CGF.EmitScalarExpr(condExpr);
4184 llvm::Value *LHS = Visit(lhsExpr);
4185 llvm::Value *RHS = Visit(rhsExpr);
4187 llvm::Type *condType = ConvertType(condExpr->getType());
4188 llvm::VectorType *vecTy = cast<llvm::VectorType>(condType);
4190 unsigned numElem = vecTy->getNumElements();
4191 llvm::Type *elemType = vecTy->getElementType();
4193 llvm::Value *zeroVec = llvm::Constant::getNullValue(vecTy);
4194 llvm::Value *TestMSB = Builder.CreateICmpSLT(CondV, zeroVec);
4195 llvm::Value *tmp = Builder.CreateSExt(TestMSB,
4196 llvm::VectorType::get(elemType,
4199 llvm::Value *tmp2 = Builder.CreateNot(tmp);
4201 // Cast float to int to perform ANDs if necessary.
4202 llvm::Value *RHSTmp = RHS;
4203 llvm::Value *LHSTmp = LHS;
4204 bool wasCast = false;
4205 llvm::VectorType *rhsVTy = cast<llvm::VectorType>(RHS->getType());
4206 if (rhsVTy->getElementType()->isFloatingPointTy()) {
4207 RHSTmp = Builder.CreateBitCast(RHS, tmp2->getType());
4208 LHSTmp = Builder.CreateBitCast(LHS, tmp->getType());
4212 llvm::Value *tmp3 = Builder.CreateAnd(RHSTmp, tmp2);
4213 llvm::Value *tmp4 = Builder.CreateAnd(LHSTmp, tmp);
4214 llvm::Value *tmp5 = Builder.CreateOr(tmp3, tmp4, "cond");
4216 tmp5 = Builder.CreateBitCast(tmp5, RHS->getType());
4221 // If this is a really simple expression (like x ? 4 : 5), emit this as a
4222 // select instead of as control flow. We can only do this if it is cheap and
4223 // safe to evaluate the LHS and RHS unconditionally.
4224 if (isCheapEnoughToEvaluateUnconditionally(lhsExpr, CGF) &&
4225 isCheapEnoughToEvaluateUnconditionally(rhsExpr, CGF)) {
4226 llvm::Value *CondV = CGF.EvaluateExprAsBool(condExpr);
4227 llvm::Value *StepV = Builder.CreateZExtOrBitCast(CondV, CGF.Int64Ty);
4229 CGF.incrementProfileCounter(E, StepV);
4231 llvm::Value *LHS = Visit(lhsExpr);
4232 llvm::Value *RHS = Visit(rhsExpr);
4234 // If the conditional has void type, make sure we return a null Value*.
4235 assert(!RHS && "LHS and RHS types must match");
4238 return Builder.CreateSelect(CondV, LHS, RHS, "cond");
4241 llvm::BasicBlock *LHSBlock = CGF.createBasicBlock("cond.true");
4242 llvm::BasicBlock *RHSBlock = CGF.createBasicBlock("cond.false");
4243 llvm::BasicBlock *ContBlock = CGF.createBasicBlock("cond.end");
4245 CodeGenFunction::ConditionalEvaluation eval(CGF);
4246 CGF.EmitBranchOnBoolExpr(condExpr, LHSBlock, RHSBlock,
4247 CGF.getProfileCount(lhsExpr));
4249 CGF.EmitBlock(LHSBlock);
4250 CGF.incrementProfileCounter(E);
4252 Value *LHS = Visit(lhsExpr);
4255 LHSBlock = Builder.GetInsertBlock();
4256 Builder.CreateBr(ContBlock);
4258 CGF.EmitBlock(RHSBlock);
4260 Value *RHS = Visit(rhsExpr);
4263 RHSBlock = Builder.GetInsertBlock();
4264 CGF.EmitBlock(ContBlock);
4266 // If the LHS or RHS is a throw expression, it will be legitimately null.
4272 // Create a PHI node for the real part.
4273 llvm::PHINode *PN = Builder.CreatePHI(LHS->getType(), 2, "cond");
4274 PN->addIncoming(LHS, LHSBlock);
4275 PN->addIncoming(RHS, RHSBlock);
4279 Value *ScalarExprEmitter::VisitChooseExpr(ChooseExpr *E) {
4280 return Visit(E->getChosenSubExpr());
4283 Value *ScalarExprEmitter::VisitVAArgExpr(VAArgExpr *VE) {
4284 QualType Ty = VE->getType();
4286 if (Ty->isVariablyModifiedType())
4287 CGF.EmitVariablyModifiedType(Ty);
4289 Address ArgValue = Address::invalid();
4290 Address ArgPtr = CGF.EmitVAArg(VE, ArgValue);
4292 llvm::Type *ArgTy = ConvertType(VE->getType());
4294 // If EmitVAArg fails, emit an error.
4295 if (!ArgPtr.isValid()) {
4296 CGF.ErrorUnsupported(VE, "va_arg expression");
4297 return llvm::UndefValue::get(ArgTy);
4300 // FIXME Volatility.
4301 llvm::Value *Val = Builder.CreateLoad(ArgPtr);
4303 // If EmitVAArg promoted the type, we must truncate it.
4304 if (ArgTy != Val->getType()) {
4305 if (ArgTy->isPointerTy() && !Val->getType()->isPointerTy())
4306 Val = Builder.CreateIntToPtr(Val, ArgTy);
4308 Val = Builder.CreateTrunc(Val, ArgTy);
4314 Value *ScalarExprEmitter::VisitBlockExpr(const BlockExpr *block) {
4315 return CGF.EmitBlockLiteral(block);
4318 // Convert a vec3 to vec4, or vice versa.
4319 static Value *ConvertVec3AndVec4(CGBuilderTy &Builder, CodeGenFunction &CGF,
4320 Value *Src, unsigned NumElementsDst) {
4321 llvm::Value *UnV = llvm::UndefValue::get(Src->getType());
4322 SmallVector<llvm::Constant*, 4> Args;
4323 Args.push_back(Builder.getInt32(0));
4324 Args.push_back(Builder.getInt32(1));
4325 Args.push_back(Builder.getInt32(2));
4326 if (NumElementsDst == 4)
4327 Args.push_back(llvm::UndefValue::get(CGF.Int32Ty));
4328 llvm::Constant *Mask = llvm::ConstantVector::get(Args);
4329 return Builder.CreateShuffleVector(Src, UnV, Mask);
4332 // Create cast instructions for converting LLVM value \p Src to LLVM type \p
4333 // DstTy. \p Src has the same size as \p DstTy. Both are single value types
4334 // but could be scalar or vectors of different lengths, and either can be
4336 // There are 4 cases:
4337 // 1. non-pointer -> non-pointer : needs 1 bitcast
4338 // 2. pointer -> pointer : needs 1 bitcast or addrspacecast
4339 // 3. pointer -> non-pointer
4340 // a) pointer -> intptr_t : needs 1 ptrtoint
4341 // b) pointer -> non-intptr_t : needs 1 ptrtoint then 1 bitcast
4342 // 4. non-pointer -> pointer
4343 // a) intptr_t -> pointer : needs 1 inttoptr
4344 // b) non-intptr_t -> pointer : needs 1 bitcast then 1 inttoptr
4345 // Note: for cases 3b and 4b two casts are required since LLVM casts do not
4346 // allow casting directly between pointer types and non-integer non-pointer
4348 static Value *createCastsForTypeOfSameSize(CGBuilderTy &Builder,
4349 const llvm::DataLayout &DL,
4350 Value *Src, llvm::Type *DstTy,
4351 StringRef Name = "") {
4352 auto SrcTy = Src->getType();
4355 if (!SrcTy->isPointerTy() && !DstTy->isPointerTy())
4356 return Builder.CreateBitCast(Src, DstTy, Name);
4359 if (SrcTy->isPointerTy() && DstTy->isPointerTy())
4360 return Builder.CreatePointerBitCastOrAddrSpaceCast(Src, DstTy, Name);
4363 if (SrcTy->isPointerTy() && !DstTy->isPointerTy()) {
4365 if (!DstTy->isIntegerTy())
4366 Src = Builder.CreatePtrToInt(Src, DL.getIntPtrType(SrcTy));
4368 return Builder.CreateBitOrPointerCast(Src, DstTy, Name);
4372 if (!SrcTy->isIntegerTy())
4373 Src = Builder.CreateBitCast(Src, DL.getIntPtrType(DstTy));
4375 return Builder.CreateIntToPtr(Src, DstTy, Name);
4378 Value *ScalarExprEmitter::VisitAsTypeExpr(AsTypeExpr *E) {
4379 Value *Src = CGF.EmitScalarExpr(E->getSrcExpr());
4380 llvm::Type *DstTy = ConvertType(E->getType());
4382 llvm::Type *SrcTy = Src->getType();
4383 unsigned NumElementsSrc = isa<llvm::VectorType>(SrcTy) ?
4384 cast<llvm::VectorType>(SrcTy)->getNumElements() : 0;
4385 unsigned NumElementsDst = isa<llvm::VectorType>(DstTy) ?
4386 cast<llvm::VectorType>(DstTy)->getNumElements() : 0;
4388 // Going from vec3 to non-vec3 is a special case and requires a shuffle
4389 // vector to get a vec4, then a bitcast if the target type is different.
4390 if (NumElementsSrc == 3 && NumElementsDst != 3) {
4391 Src = ConvertVec3AndVec4(Builder, CGF, Src, 4);
4393 if (!CGF.CGM.getCodeGenOpts().PreserveVec3Type) {
4394 Src = createCastsForTypeOfSameSize(Builder, CGF.CGM.getDataLayout(), Src,
4398 Src->setName("astype");
4402 // Going from non-vec3 to vec3 is a special case and requires a bitcast
4403 // to vec4 if the original type is not vec4, then a shuffle vector to
4405 if (NumElementsSrc != 3 && NumElementsDst == 3) {
4406 if (!CGF.CGM.getCodeGenOpts().PreserveVec3Type) {
4407 auto Vec4Ty = llvm::VectorType::get(DstTy->getVectorElementType(), 4);
4408 Src = createCastsForTypeOfSameSize(Builder, CGF.CGM.getDataLayout(), Src,
4412 Src = ConvertVec3AndVec4(Builder, CGF, Src, 3);
4413 Src->setName("astype");
4417 return Src = createCastsForTypeOfSameSize(Builder, CGF.CGM.getDataLayout(),
4418 Src, DstTy, "astype");
4421 Value *ScalarExprEmitter::VisitAtomicExpr(AtomicExpr *E) {
4422 return CGF.EmitAtomicExpr(E).getScalarVal();
4425 //===----------------------------------------------------------------------===//
4426 // Entry Point into this File
4427 //===----------------------------------------------------------------------===//
4429 /// Emit the computation of the specified expression of scalar type, ignoring
4431 Value *CodeGenFunction::EmitScalarExpr(const Expr *E, bool IgnoreResultAssign) {
4432 assert(E && hasScalarEvaluationKind(E->getType()) &&
4433 "Invalid scalar expression to emit");
4435 return ScalarExprEmitter(*this, IgnoreResultAssign)
4436 .Visit(const_cast<Expr *>(E));
4439 /// Emit a conversion from the specified type to the specified destination type,
4440 /// both of which are LLVM scalar types.
4441 Value *CodeGenFunction::EmitScalarConversion(Value *Src, QualType SrcTy,
4443 SourceLocation Loc) {
4444 assert(hasScalarEvaluationKind(SrcTy) && hasScalarEvaluationKind(DstTy) &&
4445 "Invalid scalar expression to emit");
4446 return ScalarExprEmitter(*this).EmitScalarConversion(Src, SrcTy, DstTy, Loc);
4449 /// Emit a conversion from the specified complex type to the specified
4450 /// destination type, where the destination type is an LLVM scalar type.
4451 Value *CodeGenFunction::EmitComplexToScalarConversion(ComplexPairTy Src,
4454 SourceLocation Loc) {
4455 assert(SrcTy->isAnyComplexType() && hasScalarEvaluationKind(DstTy) &&
4456 "Invalid complex -> scalar conversion");
4457 return ScalarExprEmitter(*this)
4458 .EmitComplexToScalarConversion(Src, SrcTy, DstTy, Loc);
4462 llvm::Value *CodeGenFunction::
4463 EmitScalarPrePostIncDec(const UnaryOperator *E, LValue LV,
4464 bool isInc, bool isPre) {
4465 return ScalarExprEmitter(*this).EmitScalarPrePostIncDec(E, LV, isInc, isPre);
4468 LValue CodeGenFunction::EmitObjCIsaExpr(const ObjCIsaExpr *E) {
4469 // object->isa or (*object).isa
4470 // Generate code as for: *(Class*)object
4472 Expr *BaseExpr = E->getBase();
4473 Address Addr = Address::invalid();
4474 if (BaseExpr->isRValue()) {
4475 Addr = Address(EmitScalarExpr(BaseExpr), getPointerAlign());
4477 Addr = EmitLValue(BaseExpr).getAddress();
4480 // Cast the address to Class*.
4481 Addr = Builder.CreateElementBitCast(Addr, ConvertType(E->getType()));
4482 return MakeAddrLValue(Addr, E->getType());
4486 LValue CodeGenFunction::EmitCompoundAssignmentLValue(
4487 const CompoundAssignOperator *E) {
4488 ScalarExprEmitter Scalar(*this);
4489 Value *Result = nullptr;
4490 switch (E->getOpcode()) {
4491 #define COMPOUND_OP(Op) \
4492 case BO_##Op##Assign: \
4493 return Scalar.EmitCompoundAssignLValue(E, &ScalarExprEmitter::Emit##Op, \
4530 llvm_unreachable("Not valid compound assignment operators");
4533 llvm_unreachable("Unhandled compound assignment operator");
4536 Value *CodeGenFunction::EmitCheckedInBoundsGEP(Value *Ptr,
4537 ArrayRef<Value *> IdxList,
4541 const Twine &Name) {
4542 Value *GEPVal = Builder.CreateInBoundsGEP(Ptr, IdxList, Name);
4544 // If the pointer overflow sanitizer isn't enabled, do nothing.
4545 if (!SanOpts.has(SanitizerKind::PointerOverflow))
4548 // If the GEP has already been reduced to a constant, leave it be.
4549 if (isa<llvm::Constant>(GEPVal))
4552 // Only check for overflows in the default address space.
4553 if (GEPVal->getType()->getPointerAddressSpace())
4556 auto *GEP = cast<llvm::GEPOperator>(GEPVal);
4557 assert(GEP->isInBounds() && "Expected inbounds GEP");
4559 SanitizerScope SanScope(this);
4560 auto &VMContext = getLLVMContext();
4561 const auto &DL = CGM.getDataLayout();
4562 auto *IntPtrTy = DL.getIntPtrType(GEP->getPointerOperandType());
4564 // Grab references to the signed add/mul overflow intrinsics for intptr_t.
4565 auto *Zero = llvm::ConstantInt::getNullValue(IntPtrTy);
4566 auto *SAddIntrinsic =
4567 CGM.getIntrinsic(llvm::Intrinsic::sadd_with_overflow, IntPtrTy);
4568 auto *SMulIntrinsic =
4569 CGM.getIntrinsic(llvm::Intrinsic::smul_with_overflow, IntPtrTy);
4571 // The total (signed) byte offset for the GEP.
4572 llvm::Value *TotalOffset = nullptr;
4573 // The offset overflow flag - true if the total offset overflows.
4574 llvm::Value *OffsetOverflows = Builder.getFalse();
4576 /// Return the result of the given binary operation.
4577 auto eval = [&](BinaryOperator::Opcode Opcode, llvm::Value *LHS,
4578 llvm::Value *RHS) -> llvm::Value * {
4579 assert((Opcode == BO_Add || Opcode == BO_Mul) && "Can't eval binop");
4581 // If the operands are constants, return a constant result.
4582 if (auto *LHSCI = dyn_cast<llvm::ConstantInt>(LHS)) {
4583 if (auto *RHSCI = dyn_cast<llvm::ConstantInt>(RHS)) {
4585 bool HasOverflow = mayHaveIntegerOverflow(LHSCI, RHSCI, Opcode,
4586 /*Signed=*/true, N);
4588 OffsetOverflows = Builder.getTrue();
4589 return llvm::ConstantInt::get(VMContext, N);
4593 // Otherwise, compute the result with checked arithmetic.
4594 auto *ResultAndOverflow = Builder.CreateCall(
4595 (Opcode == BO_Add) ? SAddIntrinsic : SMulIntrinsic, {LHS, RHS});
4596 OffsetOverflows = Builder.CreateOr(
4597 Builder.CreateExtractValue(ResultAndOverflow, 1), OffsetOverflows);
4598 return Builder.CreateExtractValue(ResultAndOverflow, 0);
4601 // Determine the total byte offset by looking at each GEP operand.
4602 for (auto GTI = llvm::gep_type_begin(GEP), GTE = llvm::gep_type_end(GEP);
4603 GTI != GTE; ++GTI) {
4604 llvm::Value *LocalOffset;
4605 auto *Index = GTI.getOperand();
4606 // Compute the local offset contributed by this indexing step:
4607 if (auto *STy = GTI.getStructTypeOrNull()) {
4608 // For struct indexing, the local offset is the byte position of the
4610 unsigned FieldNo = cast<llvm::ConstantInt>(Index)->getZExtValue();
4611 LocalOffset = llvm::ConstantInt::get(
4612 IntPtrTy, DL.getStructLayout(STy)->getElementOffset(FieldNo));
4614 // Otherwise this is array-like indexing. The local offset is the index
4615 // multiplied by the element size.
4616 auto *ElementSize = llvm::ConstantInt::get(
4617 IntPtrTy, DL.getTypeAllocSize(GTI.getIndexedType()));
4618 auto *IndexS = Builder.CreateIntCast(Index, IntPtrTy, /*isSigned=*/true);
4619 LocalOffset = eval(BO_Mul, ElementSize, IndexS);
4622 // If this is the first offset, set it as the total offset. Otherwise, add
4623 // the local offset into the running total.
4624 if (!TotalOffset || TotalOffset == Zero)
4625 TotalOffset = LocalOffset;
4627 TotalOffset = eval(BO_Add, TotalOffset, LocalOffset);
4630 // Common case: if the total offset is zero, don't emit a check.
4631 if (TotalOffset == Zero)
4634 // Now that we've computed the total offset, add it to the base pointer (with
4635 // wrapping semantics).
4636 auto *IntPtr = Builder.CreatePtrToInt(GEP->getPointerOperand(), IntPtrTy);
4637 auto *ComputedGEP = Builder.CreateAdd(IntPtr, TotalOffset);
4639 // The GEP is valid if:
4640 // 1) The total offset doesn't overflow, and
4641 // 2) The sign of the difference between the computed address and the base
4642 // pointer matches the sign of the total offset.
4643 llvm::Value *ValidGEP;
4644 auto *NoOffsetOverflow = Builder.CreateNot(OffsetOverflows);
4645 if (SignedIndices) {
4646 auto *PosOrZeroValid = Builder.CreateICmpUGE(ComputedGEP, IntPtr);
4647 auto *PosOrZeroOffset = Builder.CreateICmpSGE(TotalOffset, Zero);
4648 llvm::Value *NegValid = Builder.CreateICmpULT(ComputedGEP, IntPtr);
4649 ValidGEP = Builder.CreateAnd(
4650 Builder.CreateSelect(PosOrZeroOffset, PosOrZeroValid, NegValid),
4652 } else if (!SignedIndices && !IsSubtraction) {
4653 auto *PosOrZeroValid = Builder.CreateICmpUGE(ComputedGEP, IntPtr);
4654 ValidGEP = Builder.CreateAnd(PosOrZeroValid, NoOffsetOverflow);
4656 auto *NegOrZeroValid = Builder.CreateICmpULE(ComputedGEP, IntPtr);
4657 ValidGEP = Builder.CreateAnd(NegOrZeroValid, NoOffsetOverflow);
4660 llvm::Constant *StaticArgs[] = {EmitCheckSourceLocation(Loc)};
4661 // Pass the computed GEP to the runtime to avoid emitting poisoned arguments.
4662 llvm::Value *DynamicArgs[] = {IntPtr, ComputedGEP};
4663 EmitCheck(std::make_pair(ValidGEP, SanitizerKind::PointerOverflow),
4664 SanitizerHandler::PointerOverflow, StaticArgs, DynamicArgs);