CGExprScalar.cpp revision a91d6a6619a91d0ca7102d8ab5678d855f04d850
1//===--- CGExprScalar.cpp - Emit LLVM Code for Scalar Exprs ---------------===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9// 10// This contains code to emit Expr nodes with scalar LLVM types as LLVM code. 11// 12//===----------------------------------------------------------------------===// 13 14#include "CodeGenFunction.h" 15#include "CodeGenModule.h" 16#include "clang/AST/ASTContext.h" 17#include "clang/AST/DeclObjC.h" 18#include "clang/AST/RecordLayout.h" 19#include "clang/AST/StmtVisitor.h" 20#include "clang/Basic/TargetInfo.h" 21#include "llvm/Constants.h" 22#include "llvm/Function.h" 23#include "llvm/GlobalVariable.h" 24#include "llvm/Intrinsics.h" 25#include "llvm/Module.h" 26#include "llvm/Support/Compiler.h" 27#include "llvm/Support/CFG.h" 28#include "llvm/Target/TargetData.h" 29#include <cstdarg> 30 31using namespace clang; 32using namespace CodeGen; 33using llvm::Value; 34 35//===----------------------------------------------------------------------===// 36// Scalar Expression Emitter 37//===----------------------------------------------------------------------===// 38 39struct BinOpInfo { 40 Value *LHS; 41 Value *RHS; 42 QualType Ty; // Computation Type. 43 const BinaryOperator *E; 44}; 45 46namespace { 47class VISIBILITY_HIDDEN ScalarExprEmitter 48 : public StmtVisitor<ScalarExprEmitter, Value*> { 49 CodeGenFunction &CGF; 50 CGBuilderTy &Builder; 51 bool IgnoreResultAssign; 52 llvm::LLVMContext &VMContext; 53public: 54 55 ScalarExprEmitter(CodeGenFunction &cgf, bool ira=false) 56 : CGF(cgf), Builder(CGF.Builder), IgnoreResultAssign(ira), 57 VMContext(cgf.getLLVMContext()) { 58 } 59 60 //===--------------------------------------------------------------------===// 61 // Utilities 62 //===--------------------------------------------------------------------===// 63 64 bool TestAndClearIgnoreResultAssign() { 65 bool I = IgnoreResultAssign; 66 IgnoreResultAssign = false; 67 return I; 68 } 69 70 const llvm::Type *ConvertType(QualType T) { return CGF.ConvertType(T); } 71 LValue EmitLValue(const Expr *E) { return CGF.EmitLValue(E); } 72 73 Value *EmitLoadOfLValue(LValue LV, QualType T) { 74 return CGF.EmitLoadOfLValue(LV, T).getScalarVal(); 75 } 76 77 /// EmitLoadOfLValue - Given an expression with complex type that represents a 78 /// value l-value, this method emits the address of the l-value, then loads 79 /// and returns the result. 80 Value *EmitLoadOfLValue(const Expr *E) { 81 return EmitLoadOfLValue(EmitLValue(E), E->getType()); 82 } 83 84 /// EmitConversionToBool - Convert the specified expression value to a 85 /// boolean (i1) truth value. This is equivalent to "Val != 0". 86 Value *EmitConversionToBool(Value *Src, QualType DstTy); 87 88 /// EmitScalarConversion - Emit a conversion from the specified type to the 89 /// specified destination type, both of which are LLVM scalar types. 90 Value *EmitScalarConversion(Value *Src, QualType SrcTy, QualType DstTy); 91 92 /// EmitComplexToScalarConversion - Emit a conversion from the specified 93 /// complex type to the specified destination type, where the destination 94 /// type is an LLVM scalar type. 95 Value *EmitComplexToScalarConversion(CodeGenFunction::ComplexPairTy Src, 96 QualType SrcTy, QualType DstTy); 97 98 //===--------------------------------------------------------------------===// 99 // Visitor Methods 100 //===--------------------------------------------------------------------===// 101 102 Value *VisitStmt(Stmt *S) { 103 S->dump(CGF.getContext().getSourceManager()); 104 assert(0 && "Stmt can't have complex result type!"); 105 return 0; 106 } 107 Value *VisitExpr(Expr *S); 108 Value *VisitParenExpr(ParenExpr *PE) { return Visit(PE->getSubExpr()); } 109 110 // Leaves. 111 Value *VisitIntegerLiteral(const IntegerLiteral *E) { 112 return llvm::ConstantInt::get(VMContext, E->getValue()); 113 } 114 Value *VisitFloatingLiteral(const FloatingLiteral *E) { 115 return llvm::ConstantFP::get(VMContext, E->getValue()); 116 } 117 Value *VisitCharacterLiteral(const CharacterLiteral *E) { 118 return llvm::ConstantInt::get(ConvertType(E->getType()), E->getValue()); 119 } 120 Value *VisitCXXBoolLiteralExpr(const CXXBoolLiteralExpr *E) { 121 return llvm::ConstantInt::get(ConvertType(E->getType()), E->getValue()); 122 } 123 Value *VisitCXXZeroInitValueExpr(const CXXZeroInitValueExpr *E) { 124 return VMContext.getNullValue(ConvertType(E->getType())); 125 } 126 Value *VisitGNUNullExpr(const GNUNullExpr *E) { 127 return VMContext.getNullValue(ConvertType(E->getType())); 128 } 129 Value *VisitTypesCompatibleExpr(const TypesCompatibleExpr *E) { 130 return llvm::ConstantInt::get(ConvertType(E->getType()), 131 CGF.getContext().typesAreCompatible( 132 E->getArgType1(), E->getArgType2())); 133 } 134 Value *VisitSizeOfAlignOfExpr(const SizeOfAlignOfExpr *E); 135 Value *VisitAddrLabelExpr(const AddrLabelExpr *E) { 136 llvm::Value *V = 137 llvm::ConstantInt::get(llvm::Type::Int32Ty, 138 CGF.GetIDForAddrOfLabel(E->getLabel())); 139 140 return Builder.CreateIntToPtr(V, ConvertType(E->getType())); 141 } 142 143 // l-values. 144 Value *VisitDeclRefExpr(DeclRefExpr *E) { 145 if (const EnumConstantDecl *EC = dyn_cast<EnumConstantDecl>(E->getDecl())) 146 return llvm::ConstantInt::get(VMContext, EC->getInitVal()); 147 return EmitLoadOfLValue(E); 148 } 149 Value *VisitObjCSelectorExpr(ObjCSelectorExpr *E) { 150 return CGF.EmitObjCSelectorExpr(E); 151 } 152 Value *VisitObjCProtocolExpr(ObjCProtocolExpr *E) { 153 return CGF.EmitObjCProtocolExpr(E); 154 } 155 Value *VisitObjCIvarRefExpr(ObjCIvarRefExpr *E) { 156 return EmitLoadOfLValue(E); 157 } 158 Value *VisitObjCPropertyRefExpr(ObjCPropertyRefExpr *E) { 159 return EmitLoadOfLValue(E); 160 } 161 Value *VisitObjCKVCRefExpr(ObjCKVCRefExpr *E) { 162 return EmitLoadOfLValue(E); 163 } 164 Value *VisitObjCMessageExpr(ObjCMessageExpr *E) { 165 return CGF.EmitObjCMessageExpr(E).getScalarVal(); 166 } 167 168 Value *VisitArraySubscriptExpr(ArraySubscriptExpr *E); 169 Value *VisitShuffleVectorExpr(ShuffleVectorExpr *E); 170 Value *VisitMemberExpr(Expr *E) { return EmitLoadOfLValue(E); } 171 Value *VisitExtVectorElementExpr(Expr *E) { return EmitLoadOfLValue(E); } 172 Value *VisitCompoundLiteralExpr(CompoundLiteralExpr *E) { 173 return EmitLoadOfLValue(E); 174 } 175 Value *VisitStringLiteral(Expr *E) { return EmitLValue(E).getAddress(); } 176 Value *VisitObjCEncodeExpr(const ObjCEncodeExpr *E) { 177 return EmitLValue(E).getAddress(); 178 } 179 180 Value *VisitPredefinedExpr(Expr *E) { return EmitLValue(E).getAddress(); } 181 182 Value *VisitInitListExpr(InitListExpr *E) { 183 bool Ignore = TestAndClearIgnoreResultAssign(); 184 (void)Ignore; 185 assert (Ignore == false && "init list ignored"); 186 unsigned NumInitElements = E->getNumInits(); 187 188 if (E->hadArrayRangeDesignator()) { 189 CGF.ErrorUnsupported(E, "GNU array range designator extension"); 190 } 191 192 const llvm::VectorType *VType = 193 dyn_cast<llvm::VectorType>(ConvertType(E->getType())); 194 195 // We have a scalar in braces. Just use the first element. 196 if (!VType) 197 return Visit(E->getInit(0)); 198 199 unsigned NumVectorElements = VType->getNumElements(); 200 const llvm::Type *ElementType = VType->getElementType(); 201 202 // Emit individual vector element stores. 203 llvm::Value *V = VMContext.getUndef(VType); 204 205 // Emit initializers 206 unsigned i; 207 for (i = 0; i < NumInitElements; ++i) { 208 Value *NewV = Visit(E->getInit(i)); 209 Value *Idx = llvm::ConstantInt::get(llvm::Type::Int32Ty, i); 210 V = Builder.CreateInsertElement(V, NewV, Idx); 211 } 212 213 // Emit remaining default initializers 214 for (/* Do not initialize i*/; i < NumVectorElements; ++i) { 215 Value *Idx = llvm::ConstantInt::get(llvm::Type::Int32Ty, i); 216 llvm::Value *NewV = VMContext.getNullValue(ElementType); 217 V = Builder.CreateInsertElement(V, NewV, Idx); 218 } 219 220 return V; 221 } 222 223 Value *VisitImplicitValueInitExpr(const ImplicitValueInitExpr *E) { 224 return VMContext.getNullValue(ConvertType(E->getType())); 225 } 226 Value *VisitImplicitCastExpr(const ImplicitCastExpr *E); 227 Value *VisitCastExpr(const CastExpr *E) { 228 // Make sure to evaluate VLA bounds now so that we have them for later. 229 if (E->getType()->isVariablyModifiedType()) 230 CGF.EmitVLASize(E->getType()); 231 232 return EmitCastExpr(E->getSubExpr(), E->getType()); 233 } 234 Value *EmitCastExpr(const Expr *E, QualType T); 235 236 Value *VisitCallExpr(const CallExpr *E) { 237 if (E->getCallReturnType()->isReferenceType()) 238 return EmitLoadOfLValue(E); 239 240 return CGF.EmitCallExpr(E).getScalarVal(); 241 } 242 243 Value *VisitStmtExpr(const StmtExpr *E); 244 245 Value *VisitBlockDeclRefExpr(const BlockDeclRefExpr *E); 246 247 // Unary Operators. 248 Value *VisitPrePostIncDec(const UnaryOperator *E, bool isInc, bool isPre); 249 Value *VisitUnaryPostDec(const UnaryOperator *E) { 250 return VisitPrePostIncDec(E, false, false); 251 } 252 Value *VisitUnaryPostInc(const UnaryOperator *E) { 253 return VisitPrePostIncDec(E, true, false); 254 } 255 Value *VisitUnaryPreDec(const UnaryOperator *E) { 256 return VisitPrePostIncDec(E, false, true); 257 } 258 Value *VisitUnaryPreInc(const UnaryOperator *E) { 259 return VisitPrePostIncDec(E, true, true); 260 } 261 Value *VisitUnaryAddrOf(const UnaryOperator *E) { 262 return EmitLValue(E->getSubExpr()).getAddress(); 263 } 264 Value *VisitUnaryDeref(const Expr *E) { return EmitLoadOfLValue(E); } 265 Value *VisitUnaryPlus(const UnaryOperator *E) { 266 // This differs from gcc, though, most likely due to a bug in gcc. 267 TestAndClearIgnoreResultAssign(); 268 return Visit(E->getSubExpr()); 269 } 270 Value *VisitUnaryMinus (const UnaryOperator *E); 271 Value *VisitUnaryNot (const UnaryOperator *E); 272 Value *VisitUnaryLNot (const UnaryOperator *E); 273 Value *VisitUnaryReal (const UnaryOperator *E); 274 Value *VisitUnaryImag (const UnaryOperator *E); 275 Value *VisitUnaryExtension(const UnaryOperator *E) { 276 return Visit(E->getSubExpr()); 277 } 278 Value *VisitUnaryOffsetOf(const UnaryOperator *E); 279 280 // C++ 281 Value *VisitCXXDefaultArgExpr(CXXDefaultArgExpr *DAE) { 282 return Visit(DAE->getExpr()); 283 } 284 Value *VisitCXXThisExpr(CXXThisExpr *TE) { 285 return CGF.LoadCXXThis(); 286 } 287 288 Value *VisitCXXExprWithTemporaries(CXXExprWithTemporaries *E) { 289 return CGF.EmitCXXExprWithTemporaries(E).getScalarVal(); 290 } 291 Value *VisitCXXNewExpr(const CXXNewExpr *E) { 292 return CGF.EmitCXXNewExpr(E); 293 } 294 295 // Binary Operators. 296 Value *EmitMul(const BinOpInfo &Ops) { 297 if (CGF.getContext().getLangOptions().OverflowChecking 298 && Ops.Ty->isSignedIntegerType()) 299 return EmitOverflowCheckedBinOp(Ops); 300 if (Ops.LHS->getType()->isFPOrFPVector()) 301 return Builder.CreateFMul(Ops.LHS, Ops.RHS, "mul"); 302 return Builder.CreateMul(Ops.LHS, Ops.RHS, "mul"); 303 } 304 /// Create a binary op that checks for overflow. 305 /// Currently only supports +, - and *. 306 Value *EmitOverflowCheckedBinOp(const BinOpInfo &Ops); 307 Value *EmitDiv(const BinOpInfo &Ops); 308 Value *EmitRem(const BinOpInfo &Ops); 309 Value *EmitAdd(const BinOpInfo &Ops); 310 Value *EmitSub(const BinOpInfo &Ops); 311 Value *EmitShl(const BinOpInfo &Ops); 312 Value *EmitShr(const BinOpInfo &Ops); 313 Value *EmitAnd(const BinOpInfo &Ops) { 314 return Builder.CreateAnd(Ops.LHS, Ops.RHS, "and"); 315 } 316 Value *EmitXor(const BinOpInfo &Ops) { 317 return Builder.CreateXor(Ops.LHS, Ops.RHS, "xor"); 318 } 319 Value *EmitOr (const BinOpInfo &Ops) { 320 return Builder.CreateOr(Ops.LHS, Ops.RHS, "or"); 321 } 322 323 BinOpInfo EmitBinOps(const BinaryOperator *E); 324 Value *EmitCompoundAssign(const CompoundAssignOperator *E, 325 Value *(ScalarExprEmitter::*F)(const BinOpInfo &)); 326 327 // Binary operators and binary compound assignment operators. 328#define HANDLEBINOP(OP) \ 329 Value *VisitBin ## OP(const BinaryOperator *E) { \ 330 return Emit ## OP(EmitBinOps(E)); \ 331 } \ 332 Value *VisitBin ## OP ## Assign(const CompoundAssignOperator *E) { \ 333 return EmitCompoundAssign(E, &ScalarExprEmitter::Emit ## OP); \ 334 } 335 HANDLEBINOP(Mul); 336 HANDLEBINOP(Div); 337 HANDLEBINOP(Rem); 338 HANDLEBINOP(Add); 339 HANDLEBINOP(Sub); 340 HANDLEBINOP(Shl); 341 HANDLEBINOP(Shr); 342 HANDLEBINOP(And); 343 HANDLEBINOP(Xor); 344 HANDLEBINOP(Or); 345#undef HANDLEBINOP 346 347 // Comparisons. 348 Value *EmitCompare(const BinaryOperator *E, unsigned UICmpOpc, 349 unsigned SICmpOpc, unsigned FCmpOpc); 350#define VISITCOMP(CODE, UI, SI, FP) \ 351 Value *VisitBin##CODE(const BinaryOperator *E) { \ 352 return EmitCompare(E, llvm::ICmpInst::UI, llvm::ICmpInst::SI, \ 353 llvm::FCmpInst::FP); } 354 VISITCOMP(LT, ICMP_ULT, ICMP_SLT, FCMP_OLT); 355 VISITCOMP(GT, ICMP_UGT, ICMP_SGT, FCMP_OGT); 356 VISITCOMP(LE, ICMP_ULE, ICMP_SLE, FCMP_OLE); 357 VISITCOMP(GE, ICMP_UGE, ICMP_SGE, FCMP_OGE); 358 VISITCOMP(EQ, ICMP_EQ , ICMP_EQ , FCMP_OEQ); 359 VISITCOMP(NE, ICMP_NE , ICMP_NE , FCMP_UNE); 360#undef VISITCOMP 361 362 Value *VisitBinAssign (const BinaryOperator *E); 363 364 Value *VisitBinLAnd (const BinaryOperator *E); 365 Value *VisitBinLOr (const BinaryOperator *E); 366 Value *VisitBinComma (const BinaryOperator *E); 367 368 // Other Operators. 369 Value *VisitBlockExpr(const BlockExpr *BE); 370 Value *VisitConditionalOperator(const ConditionalOperator *CO); 371 Value *VisitChooseExpr(ChooseExpr *CE); 372 Value *VisitVAArgExpr(VAArgExpr *VE); 373 Value *VisitObjCStringLiteral(const ObjCStringLiteral *E) { 374 return CGF.EmitObjCStringLiteral(E); 375 } 376}; 377} // end anonymous namespace. 378 379//===----------------------------------------------------------------------===// 380// Utilities 381//===----------------------------------------------------------------------===// 382 383/// EmitConversionToBool - Convert the specified expression value to a 384/// boolean (i1) truth value. This is equivalent to "Val != 0". 385Value *ScalarExprEmitter::EmitConversionToBool(Value *Src, QualType SrcType) { 386 assert(SrcType->isCanonical() && "EmitScalarConversion strips typedefs"); 387 388 if (SrcType->isRealFloatingType()) { 389 // Compare against 0.0 for fp scalars. 390 llvm::Value *Zero = VMContext.getNullValue(Src->getType()); 391 return Builder.CreateFCmpUNE(Src, Zero, "tobool"); 392 } 393 394 assert((SrcType->isIntegerType() || isa<llvm::PointerType>(Src->getType())) && 395 "Unknown scalar type to convert"); 396 397 // Because of the type rules of C, we often end up computing a logical value, 398 // then zero extending it to int, then wanting it as a logical value again. 399 // Optimize this common case. 400 if (llvm::ZExtInst *ZI = dyn_cast<llvm::ZExtInst>(Src)) { 401 if (ZI->getOperand(0)->getType() == llvm::Type::Int1Ty) { 402 Value *Result = ZI->getOperand(0); 403 // If there aren't any more uses, zap the instruction to save space. 404 // Note that there can be more uses, for example if this 405 // is the result of an assignment. 406 if (ZI->use_empty()) 407 ZI->eraseFromParent(); 408 return Result; 409 } 410 } 411 412 // Compare against an integer or pointer null. 413 llvm::Value *Zero = VMContext.getNullValue(Src->getType()); 414 return Builder.CreateICmpNE(Src, Zero, "tobool"); 415} 416 417/// EmitScalarConversion - Emit a conversion from the specified type to the 418/// specified destination type, both of which are LLVM scalar types. 419Value *ScalarExprEmitter::EmitScalarConversion(Value *Src, QualType SrcType, 420 QualType DstType) { 421 SrcType = CGF.getContext().getCanonicalType(SrcType); 422 DstType = CGF.getContext().getCanonicalType(DstType); 423 if (SrcType == DstType) return Src; 424 425 if (DstType->isVoidType()) return 0; 426 427 // Handle conversions to bool first, they are special: comparisons against 0. 428 if (DstType->isBooleanType()) 429 return EmitConversionToBool(Src, SrcType); 430 431 const llvm::Type *DstTy = ConvertType(DstType); 432 433 // Ignore conversions like int -> uint. 434 if (Src->getType() == DstTy) 435 return Src; 436 437 // Handle pointer conversions next: pointers can only be converted 438 // to/from other pointers and integers. Check for pointer types in 439 // terms of LLVM, as some native types (like Obj-C id) may map to a 440 // pointer type. 441 if (isa<llvm::PointerType>(DstTy)) { 442 // The source value may be an integer, or a pointer. 443 if (isa<llvm::PointerType>(Src->getType())) { 444 // Some heavy lifting for derived to base conversion. 445 if (const CXXRecordDecl *ClassDecl = 446 SrcType->getCXXRecordDeclForPointerType()) 447 if (const CXXRecordDecl *BaseClassDecl = 448 DstType->getCXXRecordDeclForPointerType()) 449 Src = CGF.AddressCXXOfBaseClass(Src, ClassDecl, BaseClassDecl); 450 return Builder.CreateBitCast(Src, DstTy, "conv"); 451 } 452 assert(SrcType->isIntegerType() && "Not ptr->ptr or int->ptr conversion?"); 453 // First, convert to the correct width so that we control the kind of 454 // extension. 455 const llvm::Type *MiddleTy = VMContext.getIntegerType(CGF.LLVMPointerWidth); 456 bool InputSigned = SrcType->isSignedIntegerType(); 457 llvm::Value* IntResult = 458 Builder.CreateIntCast(Src, MiddleTy, InputSigned, "conv"); 459 // Then, cast to pointer. 460 return Builder.CreateIntToPtr(IntResult, DstTy, "conv"); 461 } 462 463 if (isa<llvm::PointerType>(Src->getType())) { 464 // Must be an ptr to int cast. 465 assert(isa<llvm::IntegerType>(DstTy) && "not ptr->int?"); 466 return Builder.CreatePtrToInt(Src, DstTy, "conv"); 467 } 468 469 // A scalar can be splatted to an extended vector of the same element type 470 if (DstType->isExtVectorType() && !isa<VectorType>(SrcType)) { 471 // Cast the scalar to element type 472 QualType EltTy = DstType->getAsExtVectorType()->getElementType(); 473 llvm::Value *Elt = EmitScalarConversion(Src, SrcType, EltTy); 474 475 // Insert the element in element zero of an undef vector 476 llvm::Value *UnV = VMContext.getUndef(DstTy); 477 llvm::Value *Idx = llvm::ConstantInt::get(llvm::Type::Int32Ty, 0); 478 UnV = Builder.CreateInsertElement(UnV, Elt, Idx, "tmp"); 479 480 // Splat the element across to all elements 481 llvm::SmallVector<llvm::Constant*, 16> Args; 482 unsigned NumElements = cast<llvm::VectorType>(DstTy)->getNumElements(); 483 for (unsigned i = 0; i < NumElements; i++) 484 Args.push_back(llvm::ConstantInt::get(llvm::Type::Int32Ty, 0)); 485 486 llvm::Constant *Mask = llvm::ConstantVector::get(&Args[0], NumElements); 487 llvm::Value *Yay = Builder.CreateShuffleVector(UnV, UnV, Mask, "splat"); 488 return Yay; 489 } 490 491 // Allow bitcast from vector to integer/fp of the same size. 492 if (isa<llvm::VectorType>(Src->getType()) || 493 isa<llvm::VectorType>(DstTy)) 494 return Builder.CreateBitCast(Src, DstTy, "conv"); 495 496 // Finally, we have the arithmetic types: real int/float. 497 if (isa<llvm::IntegerType>(Src->getType())) { 498 bool InputSigned = SrcType->isSignedIntegerType(); 499 if (isa<llvm::IntegerType>(DstTy)) 500 return Builder.CreateIntCast(Src, DstTy, InputSigned, "conv"); 501 else if (InputSigned) 502 return Builder.CreateSIToFP(Src, DstTy, "conv"); 503 else 504 return Builder.CreateUIToFP(Src, DstTy, "conv"); 505 } 506 507 assert(Src->getType()->isFloatingPoint() && "Unknown real conversion"); 508 if (isa<llvm::IntegerType>(DstTy)) { 509 if (DstType->isSignedIntegerType()) 510 return Builder.CreateFPToSI(Src, DstTy, "conv"); 511 else 512 return Builder.CreateFPToUI(Src, DstTy, "conv"); 513 } 514 515 assert(DstTy->isFloatingPoint() && "Unknown real conversion"); 516 if (DstTy->getTypeID() < Src->getType()->getTypeID()) 517 return Builder.CreateFPTrunc(Src, DstTy, "conv"); 518 else 519 return Builder.CreateFPExt(Src, DstTy, "conv"); 520} 521 522/// EmitComplexToScalarConversion - Emit a conversion from the specified 523/// complex type to the specified destination type, where the destination 524/// type is an LLVM scalar type. 525Value *ScalarExprEmitter:: 526EmitComplexToScalarConversion(CodeGenFunction::ComplexPairTy Src, 527 QualType SrcTy, QualType DstTy) { 528 // Get the source element type. 529 SrcTy = SrcTy->getAsComplexType()->getElementType(); 530 531 // Handle conversions to bool first, they are special: comparisons against 0. 532 if (DstTy->isBooleanType()) { 533 // Complex != 0 -> (Real != 0) | (Imag != 0) 534 Src.first = EmitScalarConversion(Src.first, SrcTy, DstTy); 535 Src.second = EmitScalarConversion(Src.second, SrcTy, DstTy); 536 return Builder.CreateOr(Src.first, Src.second, "tobool"); 537 } 538 539 // C99 6.3.1.7p2: "When a value of complex type is converted to a real type, 540 // the imaginary part of the complex value is discarded and the value of the 541 // real part is converted according to the conversion rules for the 542 // corresponding real type. 543 return EmitScalarConversion(Src.first, SrcTy, DstTy); 544} 545 546 547//===----------------------------------------------------------------------===// 548// Visitor Methods 549//===----------------------------------------------------------------------===// 550 551Value *ScalarExprEmitter::VisitExpr(Expr *E) { 552 CGF.ErrorUnsupported(E, "scalar expression"); 553 if (E->getType()->isVoidType()) 554 return 0; 555 return VMContext.getUndef(CGF.ConvertType(E->getType())); 556} 557 558Value *ScalarExprEmitter::VisitShuffleVectorExpr(ShuffleVectorExpr *E) { 559 llvm::SmallVector<llvm::Constant*, 32> indices; 560 for (unsigned i = 2; i < E->getNumSubExprs(); i++) { 561 indices.push_back(cast<llvm::Constant>(CGF.EmitScalarExpr(E->getExpr(i)))); 562 } 563 Value* V1 = CGF.EmitScalarExpr(E->getExpr(0)); 564 Value* V2 = CGF.EmitScalarExpr(E->getExpr(1)); 565 Value* SV = llvm::ConstantVector::get(indices.begin(), indices.size()); 566 return Builder.CreateShuffleVector(V1, V2, SV, "shuffle"); 567} 568 569Value *ScalarExprEmitter::VisitArraySubscriptExpr(ArraySubscriptExpr *E) { 570 TestAndClearIgnoreResultAssign(); 571 572 // Emit subscript expressions in rvalue context's. For most cases, this just 573 // loads the lvalue formed by the subscript expr. However, we have to be 574 // careful, because the base of a vector subscript is occasionally an rvalue, 575 // so we can't get it as an lvalue. 576 if (!E->getBase()->getType()->isVectorType()) 577 return EmitLoadOfLValue(E); 578 579 // Handle the vector case. The base must be a vector, the index must be an 580 // integer value. 581 Value *Base = Visit(E->getBase()); 582 Value *Idx = Visit(E->getIdx()); 583 bool IdxSigned = E->getIdx()->getType()->isSignedIntegerType(); 584 Idx = Builder.CreateIntCast(Idx, llvm::Type::Int32Ty, IdxSigned, 585 "vecidxcast"); 586 return Builder.CreateExtractElement(Base, Idx, "vecext"); 587} 588 589/// VisitImplicitCastExpr - Implicit casts are the same as normal casts, but 590/// also handle things like function to pointer-to-function decay, and array to 591/// pointer decay. 592Value *ScalarExprEmitter::VisitImplicitCastExpr(const ImplicitCastExpr *E) { 593 const Expr *Op = E->getSubExpr(); 594 595 // If this is due to array->pointer conversion, emit the array expression as 596 // an l-value. 597 if (Op->getType()->isArrayType()) { 598 Value *V = EmitLValue(Op).getAddress(); // Bitfields can't be arrays. 599 600 // Note that VLA pointers are always decayed, so we don't need to do 601 // anything here. 602 if (!Op->getType()->isVariableArrayType()) { 603 assert(isa<llvm::PointerType>(V->getType()) && "Expected pointer"); 604 assert(isa<llvm::ArrayType>(cast<llvm::PointerType>(V->getType()) 605 ->getElementType()) && 606 "Expected pointer to array"); 607 V = Builder.CreateStructGEP(V, 0, "arraydecay"); 608 } 609 610 // The resultant pointer type can be implicitly casted to other pointer 611 // types as well (e.g. void*) and can be implicitly converted to integer. 612 const llvm::Type *DestTy = ConvertType(E->getType()); 613 if (V->getType() != DestTy) { 614 if (isa<llvm::PointerType>(DestTy)) 615 V = Builder.CreateBitCast(V, DestTy, "ptrconv"); 616 else { 617 assert(isa<llvm::IntegerType>(DestTy) && "Unknown array decay"); 618 V = Builder.CreatePtrToInt(V, DestTy, "ptrconv"); 619 } 620 } 621 return V; 622 } 623 624 return EmitCastExpr(Op, E->getType()); 625} 626 627 628// VisitCastExpr - Emit code for an explicit or implicit cast. Implicit casts 629// have to handle a more broad range of conversions than explicit casts, as they 630// handle things like function to ptr-to-function decay etc. 631Value *ScalarExprEmitter::EmitCastExpr(const Expr *E, QualType DestTy) { 632 if (!DestTy->isVoidType()) 633 TestAndClearIgnoreResultAssign(); 634 635 // Handle cases where the source is an non-complex type. 636 637 if (!CGF.hasAggregateLLVMType(E->getType())) { 638 Value *Src = Visit(const_cast<Expr*>(E)); 639 640 // Use EmitScalarConversion to perform the conversion. 641 return EmitScalarConversion(Src, E->getType(), DestTy); 642 } 643 644 if (E->getType()->isAnyComplexType()) { 645 // Handle cases where the source is a complex type. 646 bool IgnoreImag = true; 647 bool IgnoreImagAssign = true; 648 bool IgnoreReal = IgnoreResultAssign; 649 bool IgnoreRealAssign = IgnoreResultAssign; 650 if (DestTy->isBooleanType()) 651 IgnoreImagAssign = IgnoreImag = false; 652 else if (DestTy->isVoidType()) { 653 IgnoreReal = IgnoreImag = false; 654 IgnoreRealAssign = IgnoreImagAssign = true; 655 } 656 CodeGenFunction::ComplexPairTy V 657 = CGF.EmitComplexExpr(E, IgnoreReal, IgnoreImag, IgnoreRealAssign, 658 IgnoreImagAssign); 659 return EmitComplexToScalarConversion(V, E->getType(), DestTy); 660 } 661 662 // Okay, this is a cast from an aggregate. It must be a cast to void. Just 663 // evaluate the result and return. 664 CGF.EmitAggExpr(E, 0, false, true); 665 return 0; 666} 667 668Value *ScalarExprEmitter::VisitStmtExpr(const StmtExpr *E) { 669 return CGF.EmitCompoundStmt(*E->getSubStmt(), 670 !E->getType()->isVoidType()).getScalarVal(); 671} 672 673Value *ScalarExprEmitter::VisitBlockDeclRefExpr(const BlockDeclRefExpr *E) { 674 return Builder.CreateLoad(CGF.GetAddrOfBlockDecl(E), false, "tmp"); 675} 676 677//===----------------------------------------------------------------------===// 678// Unary Operators 679//===----------------------------------------------------------------------===// 680 681Value *ScalarExprEmitter::VisitPrePostIncDec(const UnaryOperator *E, 682 bool isInc, bool isPre) { 683 LValue LV = EmitLValue(E->getSubExpr()); 684 QualType ValTy = E->getSubExpr()->getType(); 685 Value *InVal = CGF.EmitLoadOfLValue(LV, ValTy).getScalarVal(); 686 687 int AmountVal = isInc ? 1 : -1; 688 689 if (ValTy->isPointerType() && 690 ValTy->getAsPointerType()->isVariableArrayType()) { 691 // The amount of the addition/subtraction needs to account for the VLA size 692 CGF.ErrorUnsupported(E, "VLA pointer inc/dec"); 693 } 694 695 Value *NextVal; 696 if (const llvm::PointerType *PT = 697 dyn_cast<llvm::PointerType>(InVal->getType())) { 698 llvm::Constant *Inc = 699 llvm::ConstantInt::get(llvm::Type::Int32Ty, AmountVal); 700 if (!isa<llvm::FunctionType>(PT->getElementType())) { 701 QualType PTEE = ValTy->getPointeeType(); 702 if (const ObjCInterfaceType *OIT = 703 dyn_cast<ObjCInterfaceType>(PTEE)) { 704 // Handle interface types, which are not represented with a concrete type. 705 int size = CGF.getContext().getTypeSize(OIT) / 8; 706 if (!isInc) 707 size = -size; 708 Inc = llvm::ConstantInt::get(Inc->getType(), size); 709 const llvm::Type *i8Ty = 710 VMContext.getPointerTypeUnqual(llvm::Type::Int8Ty); 711 InVal = Builder.CreateBitCast(InVal, i8Ty); 712 NextVal = Builder.CreateGEP(InVal, Inc, "add.ptr"); 713 llvm::Value *lhs = LV.getAddress(); 714 lhs = Builder.CreateBitCast(lhs, VMContext.getPointerTypeUnqual(i8Ty)); 715 LV = LValue::MakeAddr(lhs, ValTy.getCVRQualifiers(), 716 CGF.getContext().getObjCGCAttrKind(ValTy)); 717 } 718 else 719 NextVal = Builder.CreateGEP(InVal, Inc, "ptrincdec"); 720 } else { 721 const llvm::Type *i8Ty = 722 VMContext.getPointerTypeUnqual(llvm::Type::Int8Ty); 723 NextVal = Builder.CreateBitCast(InVal, i8Ty, "tmp"); 724 NextVal = Builder.CreateGEP(NextVal, Inc, "ptrincdec"); 725 NextVal = Builder.CreateBitCast(NextVal, InVal->getType()); 726 } 727 } else if (InVal->getType() == llvm::Type::Int1Ty && isInc) { 728 // Bool++ is an interesting case, due to promotion rules, we get: 729 // Bool++ -> Bool = Bool+1 -> Bool = (int)Bool+1 -> 730 // Bool = ((int)Bool+1) != 0 731 // An interesting aspect of this is that increment is always true. 732 // Decrement does not have this property. 733 NextVal = VMContext.getTrue(); 734 } else if (isa<llvm::IntegerType>(InVal->getType())) { 735 NextVal = llvm::ConstantInt::get(InVal->getType(), AmountVal); 736 NextVal = Builder.CreateAdd(InVal, NextVal, isInc ? "inc" : "dec"); 737 } else { 738 // Add the inc/dec to the real part. 739 if (InVal->getType() == llvm::Type::FloatTy) 740 NextVal = 741 llvm::ConstantFP::get(VMContext, 742 llvm::APFloat(static_cast<float>(AmountVal))); 743 else if (InVal->getType() == llvm::Type::DoubleTy) 744 NextVal = 745 llvm::ConstantFP::get(VMContext, 746 llvm::APFloat(static_cast<double>(AmountVal))); 747 else { 748 llvm::APFloat F(static_cast<float>(AmountVal)); 749 bool ignored; 750 F.convert(CGF.Target.getLongDoubleFormat(), llvm::APFloat::rmTowardZero, 751 &ignored); 752 NextVal = llvm::ConstantFP::get(VMContext, F); 753 } 754 NextVal = Builder.CreateFAdd(InVal, NextVal, isInc ? "inc" : "dec"); 755 } 756 757 // Store the updated result through the lvalue. 758 if (LV.isBitfield()) 759 CGF.EmitStoreThroughBitfieldLValue(RValue::get(NextVal), LV, ValTy, 760 &NextVal); 761 else 762 CGF.EmitStoreThroughLValue(RValue::get(NextVal), LV, ValTy); 763 764 // If this is a postinc, return the value read from memory, otherwise use the 765 // updated value. 766 return isPre ? NextVal : InVal; 767} 768 769 770Value *ScalarExprEmitter::VisitUnaryMinus(const UnaryOperator *E) { 771 TestAndClearIgnoreResultAssign(); 772 Value *Op = Visit(E->getSubExpr()); 773 if (Op->getType()->isFPOrFPVector()) 774 return Builder.CreateFNeg(Op, "neg"); 775 return Builder.CreateNeg(Op, "neg"); 776} 777 778Value *ScalarExprEmitter::VisitUnaryNot(const UnaryOperator *E) { 779 TestAndClearIgnoreResultAssign(); 780 Value *Op = Visit(E->getSubExpr()); 781 return Builder.CreateNot(Op, "neg"); 782} 783 784Value *ScalarExprEmitter::VisitUnaryLNot(const UnaryOperator *E) { 785 // Compare operand to zero. 786 Value *BoolVal = CGF.EvaluateExprAsBool(E->getSubExpr()); 787 788 // Invert value. 789 // TODO: Could dynamically modify easy computations here. For example, if 790 // the operand is an icmp ne, turn into icmp eq. 791 BoolVal = Builder.CreateNot(BoolVal, "lnot"); 792 793 // ZExt result to the expr type. 794 return Builder.CreateZExt(BoolVal, ConvertType(E->getType()), "lnot.ext"); 795} 796 797/// VisitSizeOfAlignOfExpr - Return the size or alignment of the type of 798/// argument of the sizeof expression as an integer. 799Value * 800ScalarExprEmitter::VisitSizeOfAlignOfExpr(const SizeOfAlignOfExpr *E) { 801 QualType TypeToSize = E->getTypeOfArgument(); 802 if (E->isSizeOf()) { 803 if (const VariableArrayType *VAT = 804 CGF.getContext().getAsVariableArrayType(TypeToSize)) { 805 if (E->isArgumentType()) { 806 // sizeof(type) - make sure to emit the VLA size. 807 CGF.EmitVLASize(TypeToSize); 808 } else { 809 // C99 6.5.3.4p2: If the argument is an expression of type 810 // VLA, it is evaluated. 811 CGF.EmitAnyExpr(E->getArgumentExpr()); 812 } 813 814 return CGF.GetVLASize(VAT); 815 } 816 } 817 818 // If this isn't sizeof(vla), the result must be constant; use the 819 // constant folding logic so we don't have to duplicate it here. 820 Expr::EvalResult Result; 821 E->Evaluate(Result, CGF.getContext()); 822 return llvm::ConstantInt::get(VMContext, Result.Val.getInt()); 823} 824 825Value *ScalarExprEmitter::VisitUnaryReal(const UnaryOperator *E) { 826 Expr *Op = E->getSubExpr(); 827 if (Op->getType()->isAnyComplexType()) 828 return CGF.EmitComplexExpr(Op, false, true, false, true).first; 829 return Visit(Op); 830} 831Value *ScalarExprEmitter::VisitUnaryImag(const UnaryOperator *E) { 832 Expr *Op = E->getSubExpr(); 833 if (Op->getType()->isAnyComplexType()) 834 return CGF.EmitComplexExpr(Op, true, false, true, false).second; 835 836 // __imag on a scalar returns zero. Emit the subexpr to ensure side 837 // effects are evaluated, but not the actual value. 838 if (E->isLvalue(CGF.getContext()) == Expr::LV_Valid) 839 CGF.EmitLValue(Op); 840 else 841 CGF.EmitScalarExpr(Op, true); 842 return VMContext.getNullValue(ConvertType(E->getType())); 843} 844 845Value *ScalarExprEmitter::VisitUnaryOffsetOf(const UnaryOperator *E) 846{ 847 Value* ResultAsPtr = EmitLValue(E->getSubExpr()).getAddress(); 848 const llvm::Type* ResultType = ConvertType(E->getType()); 849 return Builder.CreatePtrToInt(ResultAsPtr, ResultType, "offsetof"); 850} 851 852//===----------------------------------------------------------------------===// 853// Binary Operators 854//===----------------------------------------------------------------------===// 855 856BinOpInfo ScalarExprEmitter::EmitBinOps(const BinaryOperator *E) { 857 TestAndClearIgnoreResultAssign(); 858 BinOpInfo Result; 859 Result.LHS = Visit(E->getLHS()); 860 Result.RHS = Visit(E->getRHS()); 861 Result.Ty = E->getType(); 862 Result.E = E; 863 return Result; 864} 865 866Value *ScalarExprEmitter::EmitCompoundAssign(const CompoundAssignOperator *E, 867 Value *(ScalarExprEmitter::*Func)(const BinOpInfo &)) { 868 bool Ignore = TestAndClearIgnoreResultAssign(); 869 QualType LHSTy = E->getLHS()->getType(), RHSTy = E->getRHS()->getType(); 870 871 BinOpInfo OpInfo; 872 873 if (E->getComputationResultType()->isAnyComplexType()) { 874 // This needs to go through the complex expression emitter, but 875 // it's a tad complicated to do that... I'm leaving it out for now. 876 // (Note that we do actually need the imaginary part of the RHS for 877 // multiplication and division.) 878 CGF.ErrorUnsupported(E, "complex compound assignment"); 879 return VMContext.getUndef(CGF.ConvertType(E->getType())); 880 } 881 882 // Emit the RHS first. __block variables need to have the rhs evaluated 883 // first, plus this should improve codegen a little. 884 OpInfo.RHS = Visit(E->getRHS()); 885 OpInfo.Ty = E->getComputationResultType(); 886 OpInfo.E = E; 887 // Load/convert the LHS. 888 LValue LHSLV = EmitLValue(E->getLHS()); 889 OpInfo.LHS = EmitLoadOfLValue(LHSLV, LHSTy); 890 OpInfo.LHS = EmitScalarConversion(OpInfo.LHS, LHSTy, 891 E->getComputationLHSType()); 892 893 // Expand the binary operator. 894 Value *Result = (this->*Func)(OpInfo); 895 896 // Convert the result back to the LHS type. 897 Result = EmitScalarConversion(Result, E->getComputationResultType(), LHSTy); 898 899 // Store the result value into the LHS lvalue. Bit-fields are 900 // handled specially because the result is altered by the store, 901 // i.e., [C99 6.5.16p1] 'An assignment expression has the value of 902 // the left operand after the assignment...'. 903 if (LHSLV.isBitfield()) { 904 if (!LHSLV.isVolatileQualified()) { 905 CGF.EmitStoreThroughBitfieldLValue(RValue::get(Result), LHSLV, LHSTy, 906 &Result); 907 return Result; 908 } else 909 CGF.EmitStoreThroughBitfieldLValue(RValue::get(Result), LHSLV, LHSTy); 910 } else 911 CGF.EmitStoreThroughLValue(RValue::get(Result), LHSLV, LHSTy); 912 if (Ignore) 913 return 0; 914 return EmitLoadOfLValue(LHSLV, E->getType()); 915} 916 917 918Value *ScalarExprEmitter::EmitDiv(const BinOpInfo &Ops) { 919 if (Ops.LHS->getType()->isFPOrFPVector()) 920 return Builder.CreateFDiv(Ops.LHS, Ops.RHS, "div"); 921 else if (Ops.Ty->isUnsignedIntegerType()) 922 return Builder.CreateUDiv(Ops.LHS, Ops.RHS, "div"); 923 else 924 return Builder.CreateSDiv(Ops.LHS, Ops.RHS, "div"); 925} 926 927Value *ScalarExprEmitter::EmitRem(const BinOpInfo &Ops) { 928 // Rem in C can't be a floating point type: C99 6.5.5p2. 929 if (Ops.Ty->isUnsignedIntegerType()) 930 return Builder.CreateURem(Ops.LHS, Ops.RHS, "rem"); 931 else 932 return Builder.CreateSRem(Ops.LHS, Ops.RHS, "rem"); 933} 934 935Value *ScalarExprEmitter::EmitOverflowCheckedBinOp(const BinOpInfo &Ops) { 936 unsigned IID; 937 unsigned OpID = 0; 938 939 switch (Ops.E->getOpcode()) { 940 case BinaryOperator::Add: 941 case BinaryOperator::AddAssign: 942 OpID = 1; 943 IID = llvm::Intrinsic::sadd_with_overflow; 944 break; 945 case BinaryOperator::Sub: 946 case BinaryOperator::SubAssign: 947 OpID = 2; 948 IID = llvm::Intrinsic::ssub_with_overflow; 949 break; 950 case BinaryOperator::Mul: 951 case BinaryOperator::MulAssign: 952 OpID = 3; 953 IID = llvm::Intrinsic::smul_with_overflow; 954 break; 955 default: 956 assert(false && "Unsupported operation for overflow detection"); 957 IID = 0; 958 } 959 OpID <<= 1; 960 OpID |= 1; 961 962 const llvm::Type *opTy = CGF.CGM.getTypes().ConvertType(Ops.Ty); 963 964 llvm::Function *intrinsic = CGF.CGM.getIntrinsic(IID, &opTy, 1); 965 966 Value *resultAndOverflow = Builder.CreateCall2(intrinsic, Ops.LHS, Ops.RHS); 967 Value *result = Builder.CreateExtractValue(resultAndOverflow, 0); 968 Value *overflow = Builder.CreateExtractValue(resultAndOverflow, 1); 969 970 // Branch in case of overflow. 971 llvm::BasicBlock *initialBB = Builder.GetInsertBlock(); 972 llvm::BasicBlock *overflowBB = 973 CGF.createBasicBlock("overflow", CGF.CurFn); 974 llvm::BasicBlock *continueBB = 975 CGF.createBasicBlock("overflow.continue", CGF.CurFn); 976 977 Builder.CreateCondBr(overflow, overflowBB, continueBB); 978 979 // Handle overflow 980 981 Builder.SetInsertPoint(overflowBB); 982 983 // Handler is: 984 // long long *__overflow_handler)(long long a, long long b, char op, 985 // char width) 986 std::vector<const llvm::Type*> handerArgTypes; 987 handerArgTypes.push_back(llvm::Type::Int64Ty); 988 handerArgTypes.push_back(llvm::Type::Int64Ty); 989 handerArgTypes.push_back(llvm::Type::Int8Ty); 990 handerArgTypes.push_back(llvm::Type::Int8Ty); 991 llvm::FunctionType *handlerTy = VMContext.getFunctionType(llvm::Type::Int64Ty, 992 handerArgTypes, false); 993 llvm::Value *handlerFunction = 994 CGF.CGM.getModule().getOrInsertGlobal("__overflow_handler", 995 VMContext.getPointerTypeUnqual(handlerTy)); 996 handlerFunction = Builder.CreateLoad(handlerFunction); 997 998 llvm::Value *handlerResult = Builder.CreateCall4(handlerFunction, 999 Builder.CreateSExt(Ops.LHS, llvm::Type::Int64Ty), 1000 Builder.CreateSExt(Ops.RHS, llvm::Type::Int64Ty), 1001 llvm::ConstantInt::get(llvm::Type::Int8Ty, OpID), 1002 llvm::ConstantInt::get(llvm::Type::Int8Ty, 1003 cast<llvm::IntegerType>(opTy)->getBitWidth())); 1004 1005 handlerResult = Builder.CreateTrunc(handlerResult, opTy); 1006 1007 Builder.CreateBr(continueBB); 1008 1009 // Set up the continuation 1010 Builder.SetInsertPoint(continueBB); 1011 // Get the correct result 1012 llvm::PHINode *phi = Builder.CreatePHI(opTy); 1013 phi->reserveOperandSpace(2); 1014 phi->addIncoming(result, initialBB); 1015 phi->addIncoming(handlerResult, overflowBB); 1016 1017 return phi; 1018} 1019 1020Value *ScalarExprEmitter::EmitAdd(const BinOpInfo &Ops) { 1021 if (!Ops.Ty->isAnyPointerType()) { 1022 if (CGF.getContext().getLangOptions().OverflowChecking && 1023 Ops.Ty->isSignedIntegerType()) 1024 return EmitOverflowCheckedBinOp(Ops); 1025 1026 if (Ops.LHS->getType()->isFPOrFPVector()) 1027 return Builder.CreateFAdd(Ops.LHS, Ops.RHS, "add"); 1028 1029 return Builder.CreateAdd(Ops.LHS, Ops.RHS, "add"); 1030 } 1031 1032 if (Ops.Ty->isPointerType() && 1033 Ops.Ty->getAsPointerType()->isVariableArrayType()) { 1034 // The amount of the addition needs to account for the VLA size 1035 CGF.ErrorUnsupported(Ops.E, "VLA pointer addition"); 1036 } 1037 Value *Ptr, *Idx; 1038 Expr *IdxExp; 1039 const PointerType *PT = Ops.E->getLHS()->getType()->getAsPointerType(); 1040 const ObjCObjectPointerType *OPT = 1041 Ops.E->getLHS()->getType()->getAsObjCObjectPointerType(); 1042 if (PT || OPT) { 1043 Ptr = Ops.LHS; 1044 Idx = Ops.RHS; 1045 IdxExp = Ops.E->getRHS(); 1046 } else { // int + pointer 1047 PT = Ops.E->getRHS()->getType()->getAsPointerType(); 1048 OPT = Ops.E->getRHS()->getType()->getAsObjCObjectPointerType(); 1049 assert((PT || OPT) && "Invalid add expr"); 1050 Ptr = Ops.RHS; 1051 Idx = Ops.LHS; 1052 IdxExp = Ops.E->getLHS(); 1053 } 1054 1055 unsigned Width = cast<llvm::IntegerType>(Idx->getType())->getBitWidth(); 1056 if (Width < CGF.LLVMPointerWidth) { 1057 // Zero or sign extend the pointer value based on whether the index is 1058 // signed or not. 1059 const llvm::Type *IdxType = VMContext.getIntegerType(CGF.LLVMPointerWidth); 1060 if (IdxExp->getType()->isSignedIntegerType()) 1061 Idx = Builder.CreateSExt(Idx, IdxType, "idx.ext"); 1062 else 1063 Idx = Builder.CreateZExt(Idx, IdxType, "idx.ext"); 1064 } 1065 const QualType ElementType = PT ? PT->getPointeeType() : OPT->getPointeeType(); 1066 // Handle interface types, which are not represented with a concrete 1067 // type. 1068 if (const ObjCInterfaceType *OIT = dyn_cast<ObjCInterfaceType>(ElementType)) { 1069 llvm::Value *InterfaceSize = 1070 llvm::ConstantInt::get(Idx->getType(), 1071 CGF.getContext().getTypeSize(OIT) / 8); 1072 Idx = Builder.CreateMul(Idx, InterfaceSize); 1073 const llvm::Type *i8Ty = VMContext.getPointerTypeUnqual(llvm::Type::Int8Ty); 1074 Value *Casted = Builder.CreateBitCast(Ptr, i8Ty); 1075 Value *Res = Builder.CreateGEP(Casted, Idx, "add.ptr"); 1076 return Builder.CreateBitCast(Res, Ptr->getType()); 1077 } 1078 1079 // Explicitly handle GNU void* and function pointer arithmetic 1080 // extensions. The GNU void* casts amount to no-ops since our void* 1081 // type is i8*, but this is future proof. 1082 if (ElementType->isVoidType() || ElementType->isFunctionType()) { 1083 const llvm::Type *i8Ty = VMContext.getPointerTypeUnqual(llvm::Type::Int8Ty); 1084 Value *Casted = Builder.CreateBitCast(Ptr, i8Ty); 1085 Value *Res = Builder.CreateGEP(Casted, Idx, "add.ptr"); 1086 return Builder.CreateBitCast(Res, Ptr->getType()); 1087 } 1088 1089 return Builder.CreateGEP(Ptr, Idx, "add.ptr"); 1090} 1091 1092Value *ScalarExprEmitter::EmitSub(const BinOpInfo &Ops) { 1093 if (!isa<llvm::PointerType>(Ops.LHS->getType())) { 1094 if (CGF.getContext().getLangOptions().OverflowChecking 1095 && Ops.Ty->isSignedIntegerType()) 1096 return EmitOverflowCheckedBinOp(Ops); 1097 1098 if (Ops.LHS->getType()->isFPOrFPVector()) 1099 return Builder.CreateFSub(Ops.LHS, Ops.RHS, "sub"); 1100 return Builder.CreateSub(Ops.LHS, Ops.RHS, "sub"); 1101 } 1102 1103 if (Ops.E->getLHS()->getType()->isPointerType() && 1104 Ops.E->getLHS()->getType()->getAsPointerType()->isVariableArrayType()) { 1105 // The amount of the addition needs to account for the VLA size for 1106 // ptr-int 1107 // The amount of the division needs to account for the VLA size for 1108 // ptr-ptr. 1109 CGF.ErrorUnsupported(Ops.E, "VLA pointer subtraction"); 1110 } 1111 1112 const QualType LHSType = Ops.E->getLHS()->getType(); 1113 const QualType LHSElementType = LHSType->getPointeeType(); 1114 if (!isa<llvm::PointerType>(Ops.RHS->getType())) { 1115 // pointer - int 1116 Value *Idx = Ops.RHS; 1117 unsigned Width = cast<llvm::IntegerType>(Idx->getType())->getBitWidth(); 1118 if (Width < CGF.LLVMPointerWidth) { 1119 // Zero or sign extend the pointer value based on whether the index is 1120 // signed or not. 1121 const llvm::Type *IdxType = 1122 VMContext.getIntegerType(CGF.LLVMPointerWidth); 1123 if (Ops.E->getRHS()->getType()->isSignedIntegerType()) 1124 Idx = Builder.CreateSExt(Idx, IdxType, "idx.ext"); 1125 else 1126 Idx = Builder.CreateZExt(Idx, IdxType, "idx.ext"); 1127 } 1128 Idx = Builder.CreateNeg(Idx, "sub.ptr.neg"); 1129 1130 // Handle interface types, which are not represented with a concrete 1131 // type. 1132 if (const ObjCInterfaceType *OIT = 1133 dyn_cast<ObjCInterfaceType>(LHSElementType)) { 1134 llvm::Value *InterfaceSize = 1135 llvm::ConstantInt::get(Idx->getType(), 1136 CGF.getContext().getTypeSize(OIT) / 8); 1137 Idx = Builder.CreateMul(Idx, InterfaceSize); 1138 const llvm::Type *i8Ty = 1139 VMContext.getPointerTypeUnqual(llvm::Type::Int8Ty); 1140 Value *LHSCasted = Builder.CreateBitCast(Ops.LHS, i8Ty); 1141 Value *Res = Builder.CreateGEP(LHSCasted, Idx, "add.ptr"); 1142 return Builder.CreateBitCast(Res, Ops.LHS->getType()); 1143 } 1144 1145 // Explicitly handle GNU void* and function pointer arithmetic 1146 // extensions. The GNU void* casts amount to no-ops since our 1147 // void* type is i8*, but this is future proof. 1148 if (LHSElementType->isVoidType() || LHSElementType->isFunctionType()) { 1149 const llvm::Type *i8Ty = 1150 VMContext.getPointerTypeUnqual(llvm::Type::Int8Ty); 1151 Value *LHSCasted = Builder.CreateBitCast(Ops.LHS, i8Ty); 1152 Value *Res = Builder.CreateGEP(LHSCasted, Idx, "sub.ptr"); 1153 return Builder.CreateBitCast(Res, Ops.LHS->getType()); 1154 } 1155 1156 return Builder.CreateGEP(Ops.LHS, Idx, "sub.ptr"); 1157 } else { 1158 // pointer - pointer 1159 Value *LHS = Ops.LHS; 1160 Value *RHS = Ops.RHS; 1161 1162 uint64_t ElementSize; 1163 1164 // Handle GCC extension for pointer arithmetic on void* and function pointer 1165 // types. 1166 if (LHSElementType->isVoidType() || LHSElementType->isFunctionType()) { 1167 ElementSize = 1; 1168 } else { 1169 ElementSize = CGF.getContext().getTypeSize(LHSElementType) / 8; 1170 } 1171 1172 const llvm::Type *ResultType = ConvertType(Ops.Ty); 1173 LHS = Builder.CreatePtrToInt(LHS, ResultType, "sub.ptr.lhs.cast"); 1174 RHS = Builder.CreatePtrToInt(RHS, ResultType, "sub.ptr.rhs.cast"); 1175 Value *BytesBetween = Builder.CreateSub(LHS, RHS, "sub.ptr.sub"); 1176 1177 // Optimize out the shift for element size of 1. 1178 if (ElementSize == 1) 1179 return BytesBetween; 1180 1181 // HACK: LLVM doesn't have an divide instruction that 'knows' there is no 1182 // remainder. As such, we handle common power-of-two cases here to generate 1183 // better code. See PR2247. 1184 if (llvm::isPowerOf2_64(ElementSize)) { 1185 Value *ShAmt = 1186 llvm::ConstantInt::get(ResultType, llvm::Log2_64(ElementSize)); 1187 return Builder.CreateAShr(BytesBetween, ShAmt, "sub.ptr.shr"); 1188 } 1189 1190 // Otherwise, do a full sdiv. 1191 Value *BytesPerElt = llvm::ConstantInt::get(ResultType, ElementSize); 1192 return Builder.CreateSDiv(BytesBetween, BytesPerElt, "sub.ptr.div"); 1193 } 1194} 1195 1196Value *ScalarExprEmitter::EmitShl(const BinOpInfo &Ops) { 1197 // LLVM requires the LHS and RHS to be the same type: promote or truncate the 1198 // RHS to the same size as the LHS. 1199 Value *RHS = Ops.RHS; 1200 if (Ops.LHS->getType() != RHS->getType()) 1201 RHS = Builder.CreateIntCast(RHS, Ops.LHS->getType(), false, "sh_prom"); 1202 1203 return Builder.CreateShl(Ops.LHS, RHS, "shl"); 1204} 1205 1206Value *ScalarExprEmitter::EmitShr(const BinOpInfo &Ops) { 1207 // LLVM requires the LHS and RHS to be the same type: promote or truncate the 1208 // RHS to the same size as the LHS. 1209 Value *RHS = Ops.RHS; 1210 if (Ops.LHS->getType() != RHS->getType()) 1211 RHS = Builder.CreateIntCast(RHS, Ops.LHS->getType(), false, "sh_prom"); 1212 1213 if (Ops.Ty->isUnsignedIntegerType()) 1214 return Builder.CreateLShr(Ops.LHS, RHS, "shr"); 1215 return Builder.CreateAShr(Ops.LHS, RHS, "shr"); 1216} 1217 1218Value *ScalarExprEmitter::EmitCompare(const BinaryOperator *E,unsigned UICmpOpc, 1219 unsigned SICmpOpc, unsigned FCmpOpc) { 1220 TestAndClearIgnoreResultAssign(); 1221 Value *Result; 1222 QualType LHSTy = E->getLHS()->getType(); 1223 if (!LHSTy->isAnyComplexType()) { 1224 Value *LHS = Visit(E->getLHS()); 1225 Value *RHS = Visit(E->getRHS()); 1226 1227 if (LHS->getType()->isFPOrFPVector()) { 1228 Result = Builder.CreateFCmp((llvm::CmpInst::Predicate)FCmpOpc, 1229 LHS, RHS, "cmp"); 1230 } else if (LHSTy->isSignedIntegerType()) { 1231 Result = Builder.CreateICmp((llvm::ICmpInst::Predicate)SICmpOpc, 1232 LHS, RHS, "cmp"); 1233 } else { 1234 // Unsigned integers and pointers. 1235 Result = Builder.CreateICmp((llvm::ICmpInst::Predicate)UICmpOpc, 1236 LHS, RHS, "cmp"); 1237 } 1238 1239 // If this is a vector comparison, sign extend the result to the appropriate 1240 // vector integer type and return it (don't convert to bool). 1241 if (LHSTy->isVectorType()) 1242 return Builder.CreateSExt(Result, ConvertType(E->getType()), "sext"); 1243 1244 } else { 1245 // Complex Comparison: can only be an equality comparison. 1246 CodeGenFunction::ComplexPairTy LHS = CGF.EmitComplexExpr(E->getLHS()); 1247 CodeGenFunction::ComplexPairTy RHS = CGF.EmitComplexExpr(E->getRHS()); 1248 1249 QualType CETy = LHSTy->getAsComplexType()->getElementType(); 1250 1251 Value *ResultR, *ResultI; 1252 if (CETy->isRealFloatingType()) { 1253 ResultR = Builder.CreateFCmp((llvm::FCmpInst::Predicate)FCmpOpc, 1254 LHS.first, RHS.first, "cmp.r"); 1255 ResultI = Builder.CreateFCmp((llvm::FCmpInst::Predicate)FCmpOpc, 1256 LHS.second, RHS.second, "cmp.i"); 1257 } else { 1258 // Complex comparisons can only be equality comparisons. As such, signed 1259 // and unsigned opcodes are the same. 1260 ResultR = Builder.CreateICmp((llvm::ICmpInst::Predicate)UICmpOpc, 1261 LHS.first, RHS.first, "cmp.r"); 1262 ResultI = Builder.CreateICmp((llvm::ICmpInst::Predicate)UICmpOpc, 1263 LHS.second, RHS.second, "cmp.i"); 1264 } 1265 1266 if (E->getOpcode() == BinaryOperator::EQ) { 1267 Result = Builder.CreateAnd(ResultR, ResultI, "and.ri"); 1268 } else { 1269 assert(E->getOpcode() == BinaryOperator::NE && 1270 "Complex comparison other than == or != ?"); 1271 Result = Builder.CreateOr(ResultR, ResultI, "or.ri"); 1272 } 1273 } 1274 1275 return EmitScalarConversion(Result, CGF.getContext().BoolTy, E->getType()); 1276} 1277 1278Value *ScalarExprEmitter::VisitBinAssign(const BinaryOperator *E) { 1279 bool Ignore = TestAndClearIgnoreResultAssign(); 1280 1281 // __block variables need to have the rhs evaluated first, plus this should 1282 // improve codegen just a little. 1283 Value *RHS = Visit(E->getRHS()); 1284 LValue LHS = EmitLValue(E->getLHS()); 1285 1286 // Store the value into the LHS. Bit-fields are handled specially 1287 // because the result is altered by the store, i.e., [C99 6.5.16p1] 1288 // 'An assignment expression has the value of the left operand after 1289 // the assignment...'. 1290 if (LHS.isBitfield()) { 1291 if (!LHS.isVolatileQualified()) { 1292 CGF.EmitStoreThroughBitfieldLValue(RValue::get(RHS), LHS, E->getType(), 1293 &RHS); 1294 return RHS; 1295 } else 1296 CGF.EmitStoreThroughBitfieldLValue(RValue::get(RHS), LHS, E->getType()); 1297 } else 1298 CGF.EmitStoreThroughLValue(RValue::get(RHS), LHS, E->getType()); 1299 if (Ignore) 1300 return 0; 1301 return EmitLoadOfLValue(LHS, E->getType()); 1302} 1303 1304Value *ScalarExprEmitter::VisitBinLAnd(const BinaryOperator *E) { 1305 // If we have 0 && RHS, see if we can elide RHS, if so, just return 0. 1306 // If we have 1 && X, just emit X without inserting the control flow. 1307 if (int Cond = CGF.ConstantFoldsToSimpleInteger(E->getLHS())) { 1308 if (Cond == 1) { // If we have 1 && X, just emit X. 1309 Value *RHSCond = CGF.EvaluateExprAsBool(E->getRHS()); 1310 // ZExt result to int. 1311 return Builder.CreateZExt(RHSCond, CGF.LLVMIntTy, "land.ext"); 1312 } 1313 1314 // 0 && RHS: If it is safe, just elide the RHS, and return 0. 1315 if (!CGF.ContainsLabel(E->getRHS())) 1316 return VMContext.getNullValue(CGF.LLVMIntTy); 1317 } 1318 1319 llvm::BasicBlock *ContBlock = CGF.createBasicBlock("land.end"); 1320 llvm::BasicBlock *RHSBlock = CGF.createBasicBlock("land.rhs"); 1321 1322 // Branch on the LHS first. If it is false, go to the failure (cont) block. 1323 CGF.EmitBranchOnBoolExpr(E->getLHS(), RHSBlock, ContBlock); 1324 1325 // Any edges into the ContBlock are now from an (indeterminate number of) 1326 // edges from this first condition. All of these values will be false. Start 1327 // setting up the PHI node in the Cont Block for this. 1328 llvm::PHINode *PN = llvm::PHINode::Create(llvm::Type::Int1Ty, "", ContBlock); 1329 PN->reserveOperandSpace(2); // Normal case, two inputs. 1330 for (llvm::pred_iterator PI = pred_begin(ContBlock), PE = pred_end(ContBlock); 1331 PI != PE; ++PI) 1332 PN->addIncoming(VMContext.getFalse(), *PI); 1333 1334 CGF.PushConditionalTempDestruction(); 1335 CGF.EmitBlock(RHSBlock); 1336 Value *RHSCond = CGF.EvaluateExprAsBool(E->getRHS()); 1337 CGF.PopConditionalTempDestruction(); 1338 1339 // Reaquire the RHS block, as there may be subblocks inserted. 1340 RHSBlock = Builder.GetInsertBlock(); 1341 1342 // Emit an unconditional branch from this block to ContBlock. Insert an entry 1343 // into the phi node for the edge with the value of RHSCond. 1344 CGF.EmitBlock(ContBlock); 1345 PN->addIncoming(RHSCond, RHSBlock); 1346 1347 // ZExt result to int. 1348 return Builder.CreateZExt(PN, CGF.LLVMIntTy, "land.ext"); 1349} 1350 1351Value *ScalarExprEmitter::VisitBinLOr(const BinaryOperator *E) { 1352 // If we have 1 || RHS, see if we can elide RHS, if so, just return 1. 1353 // If we have 0 || X, just emit X without inserting the control flow. 1354 if (int Cond = CGF.ConstantFoldsToSimpleInteger(E->getLHS())) { 1355 if (Cond == -1) { // If we have 0 || X, just emit X. 1356 Value *RHSCond = CGF.EvaluateExprAsBool(E->getRHS()); 1357 // ZExt result to int. 1358 return Builder.CreateZExt(RHSCond, CGF.LLVMIntTy, "lor.ext"); 1359 } 1360 1361 // 1 || RHS: If it is safe, just elide the RHS, and return 1. 1362 if (!CGF.ContainsLabel(E->getRHS())) 1363 return llvm::ConstantInt::get(CGF.LLVMIntTy, 1); 1364 } 1365 1366 llvm::BasicBlock *ContBlock = CGF.createBasicBlock("lor.end"); 1367 llvm::BasicBlock *RHSBlock = CGF.createBasicBlock("lor.rhs"); 1368 1369 // Branch on the LHS first. If it is true, go to the success (cont) block. 1370 CGF.EmitBranchOnBoolExpr(E->getLHS(), ContBlock, RHSBlock); 1371 1372 // Any edges into the ContBlock are now from an (indeterminate number of) 1373 // edges from this first condition. All of these values will be true. Start 1374 // setting up the PHI node in the Cont Block for this. 1375 llvm::PHINode *PN = llvm::PHINode::Create(llvm::Type::Int1Ty, "", ContBlock); 1376 PN->reserveOperandSpace(2); // Normal case, two inputs. 1377 for (llvm::pred_iterator PI = pred_begin(ContBlock), PE = pred_end(ContBlock); 1378 PI != PE; ++PI) 1379 PN->addIncoming(VMContext.getTrue(), *PI); 1380 1381 CGF.PushConditionalTempDestruction(); 1382 1383 // Emit the RHS condition as a bool value. 1384 CGF.EmitBlock(RHSBlock); 1385 Value *RHSCond = CGF.EvaluateExprAsBool(E->getRHS()); 1386 1387 CGF.PopConditionalTempDestruction(); 1388 1389 // Reaquire the RHS block, as there may be subblocks inserted. 1390 RHSBlock = Builder.GetInsertBlock(); 1391 1392 // Emit an unconditional branch from this block to ContBlock. Insert an entry 1393 // into the phi node for the edge with the value of RHSCond. 1394 CGF.EmitBlock(ContBlock); 1395 PN->addIncoming(RHSCond, RHSBlock); 1396 1397 // ZExt result to int. 1398 return Builder.CreateZExt(PN, CGF.LLVMIntTy, "lor.ext"); 1399} 1400 1401Value *ScalarExprEmitter::VisitBinComma(const BinaryOperator *E) { 1402 CGF.EmitStmt(E->getLHS()); 1403 CGF.EnsureInsertPoint(); 1404 return Visit(E->getRHS()); 1405} 1406 1407//===----------------------------------------------------------------------===// 1408// Other Operators 1409//===----------------------------------------------------------------------===// 1410 1411/// isCheapEnoughToEvaluateUnconditionally - Return true if the specified 1412/// expression is cheap enough and side-effect-free enough to evaluate 1413/// unconditionally instead of conditionally. This is used to convert control 1414/// flow into selects in some cases. 1415static bool isCheapEnoughToEvaluateUnconditionally(const Expr *E) { 1416 if (const ParenExpr *PE = dyn_cast<ParenExpr>(E)) 1417 return isCheapEnoughToEvaluateUnconditionally(PE->getSubExpr()); 1418 1419 // TODO: Allow anything we can constant fold to an integer or fp constant. 1420 if (isa<IntegerLiteral>(E) || isa<CharacterLiteral>(E) || 1421 isa<FloatingLiteral>(E)) 1422 return true; 1423 1424 // Non-volatile automatic variables too, to get "cond ? X : Y" where 1425 // X and Y are local variables. 1426 if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(E)) 1427 if (const VarDecl *VD = dyn_cast<VarDecl>(DRE->getDecl())) 1428 if (VD->hasLocalStorage() && !VD->getType().isVolatileQualified()) 1429 return true; 1430 1431 return false; 1432} 1433 1434 1435Value *ScalarExprEmitter:: 1436VisitConditionalOperator(const ConditionalOperator *E) { 1437 TestAndClearIgnoreResultAssign(); 1438 // If the condition constant folds and can be elided, try to avoid emitting 1439 // the condition and the dead arm. 1440 if (int Cond = CGF.ConstantFoldsToSimpleInteger(E->getCond())){ 1441 Expr *Live = E->getLHS(), *Dead = E->getRHS(); 1442 if (Cond == -1) 1443 std::swap(Live, Dead); 1444 1445 // If the dead side doesn't have labels we need, and if the Live side isn't 1446 // the gnu missing ?: extension (which we could handle, but don't bother 1447 // to), just emit the Live part. 1448 if ((!Dead || !CGF.ContainsLabel(Dead)) && // No labels in dead part 1449 Live) // Live part isn't missing. 1450 return Visit(Live); 1451 } 1452 1453 1454 // If this is a really simple expression (like x ? 4 : 5), emit this as a 1455 // select instead of as control flow. We can only do this if it is cheap and 1456 // safe to evaluate the LHS and RHS unconditionally. 1457 if (E->getLHS() && isCheapEnoughToEvaluateUnconditionally(E->getLHS()) && 1458 isCheapEnoughToEvaluateUnconditionally(E->getRHS())) { 1459 llvm::Value *CondV = CGF.EvaluateExprAsBool(E->getCond()); 1460 llvm::Value *LHS = Visit(E->getLHS()); 1461 llvm::Value *RHS = Visit(E->getRHS()); 1462 return Builder.CreateSelect(CondV, LHS, RHS, "cond"); 1463 } 1464 1465 1466 llvm::BasicBlock *LHSBlock = CGF.createBasicBlock("cond.true"); 1467 llvm::BasicBlock *RHSBlock = CGF.createBasicBlock("cond.false"); 1468 llvm::BasicBlock *ContBlock = CGF.createBasicBlock("cond.end"); 1469 Value *CondVal = 0; 1470 1471 // If we don't have the GNU missing condition extension, emit a branch on 1472 // bool the normal way. 1473 if (E->getLHS()) { 1474 // Otherwise, just use EmitBranchOnBoolExpr to get small and simple code for 1475 // the branch on bool. 1476 CGF.EmitBranchOnBoolExpr(E->getCond(), LHSBlock, RHSBlock); 1477 } else { 1478 // Otherwise, for the ?: extension, evaluate the conditional and then 1479 // convert it to bool the hard way. We do this explicitly because we need 1480 // the unconverted value for the missing middle value of the ?:. 1481 CondVal = CGF.EmitScalarExpr(E->getCond()); 1482 1483 // In some cases, EmitScalarConversion will delete the "CondVal" expression 1484 // if there are no extra uses (an optimization). Inhibit this by making an 1485 // extra dead use, because we're going to add a use of CondVal later. We 1486 // don't use the builder for this, because we don't want it to get optimized 1487 // away. This leaves dead code, but the ?: extension isn't common. 1488 new llvm::BitCastInst(CondVal, CondVal->getType(), "dummy?:holder", 1489 Builder.GetInsertBlock()); 1490 1491 Value *CondBoolVal = 1492 CGF.EmitScalarConversion(CondVal, E->getCond()->getType(), 1493 CGF.getContext().BoolTy); 1494 Builder.CreateCondBr(CondBoolVal, LHSBlock, RHSBlock); 1495 } 1496 1497 CGF.PushConditionalTempDestruction(); 1498 CGF.EmitBlock(LHSBlock); 1499 1500 // Handle the GNU extension for missing LHS. 1501 Value *LHS; 1502 if (E->getLHS()) 1503 LHS = Visit(E->getLHS()); 1504 else // Perform promotions, to handle cases like "short ?: int" 1505 LHS = EmitScalarConversion(CondVal, E->getCond()->getType(), E->getType()); 1506 1507 CGF.PopConditionalTempDestruction(); 1508 LHSBlock = Builder.GetInsertBlock(); 1509 CGF.EmitBranch(ContBlock); 1510 1511 CGF.PushConditionalTempDestruction(); 1512 CGF.EmitBlock(RHSBlock); 1513 1514 Value *RHS = Visit(E->getRHS()); 1515 CGF.PopConditionalTempDestruction(); 1516 RHSBlock = Builder.GetInsertBlock(); 1517 CGF.EmitBranch(ContBlock); 1518 1519 CGF.EmitBlock(ContBlock); 1520 1521 if (!LHS || !RHS) { 1522 assert(E->getType()->isVoidType() && "Non-void value should have a value"); 1523 return 0; 1524 } 1525 1526 // Create a PHI node for the real part. 1527 llvm::PHINode *PN = Builder.CreatePHI(LHS->getType(), "cond"); 1528 PN->reserveOperandSpace(2); 1529 PN->addIncoming(LHS, LHSBlock); 1530 PN->addIncoming(RHS, RHSBlock); 1531 return PN; 1532} 1533 1534Value *ScalarExprEmitter::VisitChooseExpr(ChooseExpr *E) { 1535 return Visit(E->getChosenSubExpr(CGF.getContext())); 1536} 1537 1538Value *ScalarExprEmitter::VisitVAArgExpr(VAArgExpr *VE) { 1539 llvm::Value *ArgValue = CGF.EmitVAListRef(VE->getSubExpr()); 1540 llvm::Value *ArgPtr = CGF.EmitVAArg(ArgValue, VE->getType()); 1541 1542 // If EmitVAArg fails, we fall back to the LLVM instruction. 1543 if (!ArgPtr) 1544 return Builder.CreateVAArg(ArgValue, ConvertType(VE->getType())); 1545 1546 // FIXME Volatility. 1547 return Builder.CreateLoad(ArgPtr); 1548} 1549 1550Value *ScalarExprEmitter::VisitBlockExpr(const BlockExpr *BE) { 1551 return CGF.BuildBlockLiteralTmp(BE); 1552} 1553 1554//===----------------------------------------------------------------------===// 1555// Entry Point into this File 1556//===----------------------------------------------------------------------===// 1557 1558/// EmitScalarExpr - Emit the computation of the specified expression of 1559/// scalar type, ignoring the result. 1560Value *CodeGenFunction::EmitScalarExpr(const Expr *E, bool IgnoreResultAssign) { 1561 assert(E && !hasAggregateLLVMType(E->getType()) && 1562 "Invalid scalar expression to emit"); 1563 1564 return ScalarExprEmitter(*this, IgnoreResultAssign) 1565 .Visit(const_cast<Expr*>(E)); 1566} 1567 1568/// EmitScalarConversion - Emit a conversion from the specified type to the 1569/// specified destination type, both of which are LLVM scalar types. 1570Value *CodeGenFunction::EmitScalarConversion(Value *Src, QualType SrcTy, 1571 QualType DstTy) { 1572 assert(!hasAggregateLLVMType(SrcTy) && !hasAggregateLLVMType(DstTy) && 1573 "Invalid scalar expression to emit"); 1574 return ScalarExprEmitter(*this).EmitScalarConversion(Src, SrcTy, DstTy); 1575} 1576 1577/// EmitComplexToScalarConversion - Emit a conversion from the specified 1578/// complex type to the specified destination type, where the destination 1579/// type is an LLVM scalar type. 1580Value *CodeGenFunction::EmitComplexToScalarConversion(ComplexPairTy Src, 1581 QualType SrcTy, 1582 QualType DstTy) { 1583 assert(SrcTy->isAnyComplexType() && !hasAggregateLLVMType(DstTy) && 1584 "Invalid complex -> scalar conversion"); 1585 return ScalarExprEmitter(*this).EmitComplexToScalarConversion(Src, SrcTy, 1586 DstTy); 1587} 1588 1589Value *CodeGenFunction::EmitShuffleVector(Value* V1, Value *V2, ...) { 1590 assert(V1->getType() == V2->getType() && 1591 "Vector operands must be of the same type"); 1592 unsigned NumElements = 1593 cast<llvm::VectorType>(V1->getType())->getNumElements(); 1594 1595 va_list va; 1596 va_start(va, V2); 1597 1598 llvm::SmallVector<llvm::Constant*, 16> Args; 1599 for (unsigned i = 0; i < NumElements; i++) { 1600 int n = va_arg(va, int); 1601 assert(n >= 0 && n < (int)NumElements * 2 && 1602 "Vector shuffle index out of bounds!"); 1603 Args.push_back(llvm::ConstantInt::get(llvm::Type::Int32Ty, n)); 1604 } 1605 1606 const char *Name = va_arg(va, const char *); 1607 va_end(va); 1608 1609 llvm::Constant *Mask = llvm::ConstantVector::get(&Args[0], NumElements); 1610 1611 return Builder.CreateShuffleVector(V1, V2, Mask, Name); 1612} 1613 1614llvm::Value *CodeGenFunction::EmitVector(llvm::Value * const *Vals, 1615 unsigned NumVals, bool isSplat) { 1616 llvm::Value *Vec 1617 = VMContext.getUndef(VMContext.getVectorType(Vals[0]->getType(), NumVals)); 1618 1619 for (unsigned i = 0, e = NumVals; i != e; ++i) { 1620 llvm::Value *Val = isSplat ? Vals[0] : Vals[i]; 1621 llvm::Value *Idx = llvm::ConstantInt::get(llvm::Type::Int32Ty, i); 1622 Vec = Builder.CreateInsertElement(Vec, Val, Idx, "tmp"); 1623 } 1624 1625 return Vec; 1626} 1627