CGExprScalar.cpp revision 62a11a78c2616ce1fa3ef7b1a4bc3f42365cafb9
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/StmtVisitor.h" 19#include "clang/Basic/TargetInfo.h" 20#include "llvm/Constants.h" 21#include "llvm/Function.h" 22#include "llvm/GlobalVariable.h" 23#include "llvm/Intrinsics.h" 24#include "llvm/Module.h" 25#include "llvm/Support/Compiler.h" 26#include "llvm/Support/CFG.h" 27#include "llvm/Target/TargetData.h" 28#include <cstdarg> 29 30using namespace clang; 31using namespace CodeGen; 32using llvm::Value; 33 34//===----------------------------------------------------------------------===// 35// Scalar Expression Emitter 36//===----------------------------------------------------------------------===// 37 38struct BinOpInfo { 39 Value *LHS; 40 Value *RHS; 41 QualType Ty; // Computation Type. 42 const BinaryOperator *E; 43}; 44 45namespace { 46class VISIBILITY_HIDDEN ScalarExprEmitter 47 : public StmtVisitor<ScalarExprEmitter, Value*> { 48 CodeGenFunction &CGF; 49 CGBuilderTy &Builder; 50 bool IgnoreResultAssign; 51 llvm::LLVMContext &VMContext; 52public: 53 54 ScalarExprEmitter(CodeGenFunction &cgf, bool ira=false) 55 : CGF(cgf), Builder(CGF.Builder), IgnoreResultAssign(ira), 56 VMContext(cgf.getLLVMContext()) { 57 } 58 59 //===--------------------------------------------------------------------===// 60 // Utilities 61 //===--------------------------------------------------------------------===// 62 63 bool TestAndClearIgnoreResultAssign() { 64 bool I = IgnoreResultAssign; 65 IgnoreResultAssign = false; 66 return I; 67 } 68 69 const llvm::Type *ConvertType(QualType T) { return CGF.ConvertType(T); } 70 LValue EmitLValue(const Expr *E) { return CGF.EmitLValue(E); } 71 72 Value *EmitLoadOfLValue(LValue LV, QualType T) { 73 return CGF.EmitLoadOfLValue(LV, T).getScalarVal(); 74 } 75 76 /// EmitLoadOfLValue - Given an expression with complex type that represents a 77 /// value l-value, this method emits the address of the l-value, then loads 78 /// and returns the result. 79 Value *EmitLoadOfLValue(const Expr *E) { 80 return EmitLoadOfLValue(EmitLValue(E), E->getType()); 81 } 82 83 /// EmitConversionToBool - Convert the specified expression value to a 84 /// boolean (i1) truth value. This is equivalent to "Val != 0". 85 Value *EmitConversionToBool(Value *Src, QualType DstTy); 86 87 /// EmitScalarConversion - Emit a conversion from the specified type to the 88 /// specified destination type, both of which are LLVM scalar types. 89 Value *EmitScalarConversion(Value *Src, QualType SrcTy, QualType DstTy); 90 91 /// EmitComplexToScalarConversion - Emit a conversion from the specified 92 /// complex type to the specified destination type, where the destination 93 /// type is an LLVM scalar type. 94 Value *EmitComplexToScalarConversion(CodeGenFunction::ComplexPairTy Src, 95 QualType SrcTy, QualType DstTy); 96 97 //===--------------------------------------------------------------------===// 98 // Visitor Methods 99 //===--------------------------------------------------------------------===// 100 101 Value *VisitStmt(Stmt *S) { 102 S->dump(CGF.getContext().getSourceManager()); 103 assert(0 && "Stmt can't have complex result type!"); 104 return 0; 105 } 106 Value *VisitExpr(Expr *S); 107 Value *VisitParenExpr(ParenExpr *PE) { return Visit(PE->getSubExpr()); } 108 109 // Leaves. 110 Value *VisitIntegerLiteral(const IntegerLiteral *E) { 111 return VMContext.getConstantInt(E->getValue()); 112 } 113 Value *VisitFloatingLiteral(const FloatingLiteral *E) { 114 return VMContext.getConstantFP(E->getValue()); 115 } 116 Value *VisitCharacterLiteral(const CharacterLiteral *E) { 117 return VMContext.getConstantInt(ConvertType(E->getType()), E->getValue()); 118 } 119 Value *VisitCXXBoolLiteralExpr(const CXXBoolLiteralExpr *E) { 120 return VMContext.getConstantInt(ConvertType(E->getType()), E->getValue()); 121 } 122 Value *VisitCXXZeroInitValueExpr(const CXXZeroInitValueExpr *E) { 123 return VMContext.getNullValue(ConvertType(E->getType())); 124 } 125 Value *VisitGNUNullExpr(const GNUNullExpr *E) { 126 return VMContext.getNullValue(ConvertType(E->getType())); 127 } 128 Value *VisitTypesCompatibleExpr(const TypesCompatibleExpr *E) { 129 return VMContext.getConstantInt(ConvertType(E->getType()), 130 CGF.getContext().typesAreCompatible( 131 E->getArgType1(), E->getArgType2())); 132 } 133 Value *VisitSizeOfAlignOfExpr(const SizeOfAlignOfExpr *E); 134 Value *VisitAddrLabelExpr(const AddrLabelExpr *E) { 135 llvm::Value *V = 136 VMContext.getConstantInt(llvm::Type::Int32Ty, 137 CGF.GetIDForAddrOfLabel(E->getLabel())); 138 139 return Builder.CreateIntToPtr(V, ConvertType(E->getType())); 140 } 141 142 // l-values. 143 Value *VisitDeclRefExpr(DeclRefExpr *E) { 144 if (const EnumConstantDecl *EC = dyn_cast<EnumConstantDecl>(E->getDecl())) 145 return VMContext.getConstantInt(EC->getInitVal()); 146 return EmitLoadOfLValue(E); 147 } 148 Value *VisitObjCSelectorExpr(ObjCSelectorExpr *E) { 149 return CGF.EmitObjCSelectorExpr(E); 150 } 151 Value *VisitObjCProtocolExpr(ObjCProtocolExpr *E) { 152 return CGF.EmitObjCProtocolExpr(E); 153 } 154 Value *VisitObjCIvarRefExpr(ObjCIvarRefExpr *E) { 155 return EmitLoadOfLValue(E); 156 } 157 Value *VisitObjCPropertyRefExpr(ObjCPropertyRefExpr *E) { 158 return EmitLoadOfLValue(E); 159 } 160 Value *VisitObjCKVCRefExpr(ObjCKVCRefExpr *E) { 161 return EmitLoadOfLValue(E); 162 } 163 Value *VisitObjCMessageExpr(ObjCMessageExpr *E) { 164 return CGF.EmitObjCMessageExpr(E).getScalarVal(); 165 } 166 167 Value *VisitArraySubscriptExpr(ArraySubscriptExpr *E); 168 Value *VisitShuffleVectorExpr(ShuffleVectorExpr *E); 169 Value *VisitMemberExpr(Expr *E) { return EmitLoadOfLValue(E); } 170 Value *VisitExtVectorElementExpr(Expr *E) { return EmitLoadOfLValue(E); } 171 Value *VisitCompoundLiteralExpr(CompoundLiteralExpr *E) { 172 return EmitLoadOfLValue(E); 173 } 174 Value *VisitStringLiteral(Expr *E) { return EmitLValue(E).getAddress(); } 175 Value *VisitObjCEncodeExpr(const ObjCEncodeExpr *E) { 176 return EmitLValue(E).getAddress(); 177 } 178 179 Value *VisitPredefinedExpr(Expr *E) { return EmitLValue(E).getAddress(); } 180 181 Value *VisitInitListExpr(InitListExpr *E) { 182 bool Ignore = TestAndClearIgnoreResultAssign(); 183 (void)Ignore; 184 assert (Ignore == false && "init list ignored"); 185 unsigned NumInitElements = E->getNumInits(); 186 187 if (E->hadArrayRangeDesignator()) { 188 CGF.ErrorUnsupported(E, "GNU array range designator extension"); 189 } 190 191 const llvm::VectorType *VType = 192 dyn_cast<llvm::VectorType>(ConvertType(E->getType())); 193 194 // We have a scalar in braces. Just use the first element. 195 if (!VType) 196 return Visit(E->getInit(0)); 197 198 unsigned NumVectorElements = VType->getNumElements(); 199 const llvm::Type *ElementType = VType->getElementType(); 200 201 // Emit individual vector element stores. 202 llvm::Value *V = VMContext.getUndef(VType); 203 204 // Emit initializers 205 unsigned i; 206 for (i = 0; i < NumInitElements; ++i) { 207 Value *NewV = Visit(E->getInit(i)); 208 Value *Idx = VMContext.getConstantInt(llvm::Type::Int32Ty, i); 209 V = Builder.CreateInsertElement(V, NewV, Idx); 210 } 211 212 // Emit remaining default initializers 213 for (/* Do not initialize i*/; i < NumVectorElements; ++i) { 214 Value *Idx = VMContext.getConstantInt(llvm::Type::Int32Ty, i); 215 llvm::Value *NewV = VMContext.getNullValue(ElementType); 216 V = Builder.CreateInsertElement(V, NewV, Idx); 217 } 218 219 return V; 220 } 221 222 Value *VisitImplicitValueInitExpr(const ImplicitValueInitExpr *E) { 223 return VMContext.getNullValue(ConvertType(E->getType())); 224 } 225 Value *VisitImplicitCastExpr(const ImplicitCastExpr *E); 226 Value *VisitCastExpr(const CastExpr *E) { 227 // Make sure to evaluate VLA bounds now so that we have them for later. 228 if (E->getType()->isVariablyModifiedType()) 229 CGF.EmitVLASize(E->getType()); 230 231 return EmitCastExpr(E->getSubExpr(), E->getType()); 232 } 233 Value *EmitCastExpr(const Expr *E, QualType T); 234 235 Value *VisitCallExpr(const CallExpr *E) { 236 if (E->getCallReturnType()->isReferenceType()) 237 return EmitLoadOfLValue(E); 238 239 return CGF.EmitCallExpr(E).getScalarVal(); 240 } 241 242 Value *VisitStmtExpr(const StmtExpr *E); 243 244 Value *VisitBlockDeclRefExpr(const BlockDeclRefExpr *E); 245 246 // Unary Operators. 247 Value *VisitPrePostIncDec(const UnaryOperator *E, bool isInc, bool isPre); 248 Value *VisitUnaryPostDec(const UnaryOperator *E) { 249 return VisitPrePostIncDec(E, false, false); 250 } 251 Value *VisitUnaryPostInc(const UnaryOperator *E) { 252 return VisitPrePostIncDec(E, true, false); 253 } 254 Value *VisitUnaryPreDec(const UnaryOperator *E) { 255 return VisitPrePostIncDec(E, false, true); 256 } 257 Value *VisitUnaryPreInc(const UnaryOperator *E) { 258 return VisitPrePostIncDec(E, true, true); 259 } 260 Value *VisitUnaryAddrOf(const UnaryOperator *E) { 261 return EmitLValue(E->getSubExpr()).getAddress(); 262 } 263 Value *VisitUnaryDeref(const Expr *E) { return EmitLoadOfLValue(E); } 264 Value *VisitUnaryPlus(const UnaryOperator *E) { 265 // This differs from gcc, though, most likely due to a bug in gcc. 266 TestAndClearIgnoreResultAssign(); 267 return Visit(E->getSubExpr()); 268 } 269 Value *VisitUnaryMinus (const UnaryOperator *E); 270 Value *VisitUnaryNot (const UnaryOperator *E); 271 Value *VisitUnaryLNot (const UnaryOperator *E); 272 Value *VisitUnaryReal (const UnaryOperator *E); 273 Value *VisitUnaryImag (const UnaryOperator *E); 274 Value *VisitUnaryExtension(const UnaryOperator *E) { 275 return Visit(E->getSubExpr()); 276 } 277 Value *VisitUnaryOffsetOf(const UnaryOperator *E); 278 279 // C++ 280 Value *VisitCXXDefaultArgExpr(CXXDefaultArgExpr *DAE) { 281 return Visit(DAE->getExpr()); 282 } 283 Value *VisitCXXThisExpr(CXXThisExpr *TE) { 284 return CGF.LoadCXXThis(); 285 } 286 287 Value *VisitCXXExprWithTemporaries(CXXExprWithTemporaries *E) { 288 return CGF.EmitCXXExprWithTemporaries(E).getScalarVal(); 289 } 290 Value *VisitCXXNewExpr(const CXXNewExpr *E) { 291 return CGF.EmitCXXNewExpr(E); 292 } 293 294 // Binary Operators. 295 Value *EmitMul(const BinOpInfo &Ops) { 296 if (CGF.getContext().getLangOptions().OverflowChecking 297 && Ops.Ty->isSignedIntegerType()) 298 return EmitOverflowCheckedBinOp(Ops); 299 if (Ops.LHS->getType()->isFPOrFPVector()) 300 return Builder.CreateFMul(Ops.LHS, Ops.RHS, "mul"); 301 return Builder.CreateMul(Ops.LHS, Ops.RHS, "mul"); 302 } 303 /// Create a binary op that checks for overflow. 304 /// Currently only supports +, - and *. 305 Value *EmitOverflowCheckedBinOp(const BinOpInfo &Ops); 306 Value *EmitDiv(const BinOpInfo &Ops); 307 Value *EmitRem(const BinOpInfo &Ops); 308 Value *EmitAdd(const BinOpInfo &Ops); 309 Value *EmitSub(const BinOpInfo &Ops); 310 Value *EmitShl(const BinOpInfo &Ops); 311 Value *EmitShr(const BinOpInfo &Ops); 312 Value *EmitAnd(const BinOpInfo &Ops) { 313 return Builder.CreateAnd(Ops.LHS, Ops.RHS, "and"); 314 } 315 Value *EmitXor(const BinOpInfo &Ops) { 316 return Builder.CreateXor(Ops.LHS, Ops.RHS, "xor"); 317 } 318 Value *EmitOr (const BinOpInfo &Ops) { 319 return Builder.CreateOr(Ops.LHS, Ops.RHS, "or"); 320 } 321 322 BinOpInfo EmitBinOps(const BinaryOperator *E); 323 Value *EmitCompoundAssign(const CompoundAssignOperator *E, 324 Value *(ScalarExprEmitter::*F)(const BinOpInfo &)); 325 326 // Binary operators and binary compound assignment operators. 327#define HANDLEBINOP(OP) \ 328 Value *VisitBin ## OP(const BinaryOperator *E) { \ 329 return Emit ## OP(EmitBinOps(E)); \ 330 } \ 331 Value *VisitBin ## OP ## Assign(const CompoundAssignOperator *E) { \ 332 return EmitCompoundAssign(E, &ScalarExprEmitter::Emit ## OP); \ 333 } 334 HANDLEBINOP(Mul); 335 HANDLEBINOP(Div); 336 HANDLEBINOP(Rem); 337 HANDLEBINOP(Add); 338 HANDLEBINOP(Sub); 339 HANDLEBINOP(Shl); 340 HANDLEBINOP(Shr); 341 HANDLEBINOP(And); 342 HANDLEBINOP(Xor); 343 HANDLEBINOP(Or); 344#undef HANDLEBINOP 345 346 // Comparisons. 347 Value *EmitCompare(const BinaryOperator *E, unsigned UICmpOpc, 348 unsigned SICmpOpc, unsigned FCmpOpc); 349#define VISITCOMP(CODE, UI, SI, FP) \ 350 Value *VisitBin##CODE(const BinaryOperator *E) { \ 351 return EmitCompare(E, llvm::ICmpInst::UI, llvm::ICmpInst::SI, \ 352 llvm::FCmpInst::FP); } 353 VISITCOMP(LT, ICMP_ULT, ICMP_SLT, FCMP_OLT); 354 VISITCOMP(GT, ICMP_UGT, ICMP_SGT, FCMP_OGT); 355 VISITCOMP(LE, ICMP_ULE, ICMP_SLE, FCMP_OLE); 356 VISITCOMP(GE, ICMP_UGE, ICMP_SGE, FCMP_OGE); 357 VISITCOMP(EQ, ICMP_EQ , ICMP_EQ , FCMP_OEQ); 358 VISITCOMP(NE, ICMP_NE , ICMP_NE , FCMP_UNE); 359#undef VISITCOMP 360 361 Value *VisitBinAssign (const BinaryOperator *E); 362 363 Value *VisitBinLAnd (const BinaryOperator *E); 364 Value *VisitBinLOr (const BinaryOperator *E); 365 Value *VisitBinComma (const BinaryOperator *E); 366 367 // Other Operators. 368 Value *VisitBlockExpr(const BlockExpr *BE); 369 Value *VisitConditionalOperator(const ConditionalOperator *CO); 370 Value *VisitChooseExpr(ChooseExpr *CE); 371 Value *VisitVAArgExpr(VAArgExpr *VE); 372 Value *VisitObjCStringLiteral(const ObjCStringLiteral *E) { 373 return CGF.EmitObjCStringLiteral(E); 374 } 375}; 376} // end anonymous namespace. 377 378//===----------------------------------------------------------------------===// 379// Utilities 380//===----------------------------------------------------------------------===// 381 382/// EmitConversionToBool - Convert the specified expression value to a 383/// boolean (i1) truth value. This is equivalent to "Val != 0". 384Value *ScalarExprEmitter::EmitConversionToBool(Value *Src, QualType SrcType) { 385 assert(SrcType->isCanonical() && "EmitScalarConversion strips typedefs"); 386 387 if (SrcType->isRealFloatingType()) { 388 // Compare against 0.0 for fp scalars. 389 llvm::Value *Zero = VMContext.getNullValue(Src->getType()); 390 return Builder.CreateFCmpUNE(Src, Zero, "tobool"); 391 } 392 393 assert((SrcType->isIntegerType() || isa<llvm::PointerType>(Src->getType())) && 394 "Unknown scalar type to convert"); 395 396 // Because of the type rules of C, we often end up computing a logical value, 397 // then zero extending it to int, then wanting it as a logical value again. 398 // Optimize this common case. 399 if (llvm::ZExtInst *ZI = dyn_cast<llvm::ZExtInst>(Src)) { 400 if (ZI->getOperand(0)->getType() == llvm::Type::Int1Ty) { 401 Value *Result = ZI->getOperand(0); 402 // If there aren't any more uses, zap the instruction to save space. 403 // Note that there can be more uses, for example if this 404 // is the result of an assignment. 405 if (ZI->use_empty()) 406 ZI->eraseFromParent(); 407 return Result; 408 } 409 } 410 411 // Compare against an integer or pointer null. 412 llvm::Value *Zero = VMContext.getNullValue(Src->getType()); 413 return Builder.CreateICmpNE(Src, Zero, "tobool"); 414} 415 416/// EmitScalarConversion - Emit a conversion from the specified type to the 417/// specified destination type, both of which are LLVM scalar types. 418Value *ScalarExprEmitter::EmitScalarConversion(Value *Src, QualType SrcType, 419 QualType DstType) { 420 SrcType = CGF.getContext().getCanonicalType(SrcType); 421 DstType = CGF.getContext().getCanonicalType(DstType); 422 if (SrcType == DstType) return Src; 423 424 if (DstType->isVoidType()) return 0; 425 426 // Handle conversions to bool first, they are special: comparisons against 0. 427 if (DstType->isBooleanType()) 428 return EmitConversionToBool(Src, SrcType); 429 430 const llvm::Type *DstTy = ConvertType(DstType); 431 432 // Ignore conversions like int -> uint. 433 if (Src->getType() == DstTy) 434 return Src; 435 436 // Handle pointer conversions next: pointers can only be converted 437 // to/from other pointers and integers. Check for pointer types in 438 // terms of LLVM, as some native types (like Obj-C id) may map to a 439 // pointer type. 440 if (isa<llvm::PointerType>(DstTy)) { 441 // The source value may be an integer, or a pointer. 442 if (isa<llvm::PointerType>(Src->getType())) 443 return Builder.CreateBitCast(Src, DstTy, "conv"); 444 assert(SrcType->isIntegerType() && "Not ptr->ptr or int->ptr conversion?"); 445 // First, convert to the correct width so that we control the kind of 446 // extension. 447 const llvm::Type *MiddleTy = VMContext.getIntegerType(CGF.LLVMPointerWidth); 448 bool InputSigned = SrcType->isSignedIntegerType(); 449 llvm::Value* IntResult = 450 Builder.CreateIntCast(Src, MiddleTy, InputSigned, "conv"); 451 // Then, cast to pointer. 452 return Builder.CreateIntToPtr(IntResult, DstTy, "conv"); 453 } 454 455 if (isa<llvm::PointerType>(Src->getType())) { 456 // Must be an ptr to int cast. 457 assert(isa<llvm::IntegerType>(DstTy) && "not ptr->int?"); 458 return Builder.CreatePtrToInt(Src, DstTy, "conv"); 459 } 460 461 // A scalar can be splatted to an extended vector of the same element type 462 if (DstType->isExtVectorType() && !isa<VectorType>(SrcType)) { 463 // Cast the scalar to element type 464 QualType EltTy = DstType->getAsExtVectorType()->getElementType(); 465 llvm::Value *Elt = EmitScalarConversion(Src, SrcType, EltTy); 466 467 // Insert the element in element zero of an undef vector 468 llvm::Value *UnV = VMContext.getUndef(DstTy); 469 llvm::Value *Idx = VMContext.getConstantInt(llvm::Type::Int32Ty, 0); 470 UnV = Builder.CreateInsertElement(UnV, Elt, Idx, "tmp"); 471 472 // Splat the element across to all elements 473 llvm::SmallVector<llvm::Constant*, 16> Args; 474 unsigned NumElements = cast<llvm::VectorType>(DstTy)->getNumElements(); 475 for (unsigned i = 0; i < NumElements; i++) 476 Args.push_back(VMContext.getConstantInt(llvm::Type::Int32Ty, 0)); 477 478 llvm::Constant *Mask = VMContext.getConstantVector(&Args[0], NumElements); 479 llvm::Value *Yay = Builder.CreateShuffleVector(UnV, UnV, Mask, "splat"); 480 return Yay; 481 } 482 483 // Allow bitcast from vector to integer/fp of the same size. 484 if (isa<llvm::VectorType>(Src->getType()) || 485 isa<llvm::VectorType>(DstTy)) 486 return Builder.CreateBitCast(Src, DstTy, "conv"); 487 488 // Finally, we have the arithmetic types: real int/float. 489 if (isa<llvm::IntegerType>(Src->getType())) { 490 bool InputSigned = SrcType->isSignedIntegerType(); 491 if (isa<llvm::IntegerType>(DstTy)) 492 return Builder.CreateIntCast(Src, DstTy, InputSigned, "conv"); 493 else if (InputSigned) 494 return Builder.CreateSIToFP(Src, DstTy, "conv"); 495 else 496 return Builder.CreateUIToFP(Src, DstTy, "conv"); 497 } 498 499 assert(Src->getType()->isFloatingPoint() && "Unknown real conversion"); 500 if (isa<llvm::IntegerType>(DstTy)) { 501 if (DstType->isSignedIntegerType()) 502 return Builder.CreateFPToSI(Src, DstTy, "conv"); 503 else 504 return Builder.CreateFPToUI(Src, DstTy, "conv"); 505 } 506 507 assert(DstTy->isFloatingPoint() && "Unknown real conversion"); 508 if (DstTy->getTypeID() < Src->getType()->getTypeID()) 509 return Builder.CreateFPTrunc(Src, DstTy, "conv"); 510 else 511 return Builder.CreateFPExt(Src, DstTy, "conv"); 512} 513 514/// EmitComplexToScalarConversion - Emit a conversion from the specified 515/// complex type to the specified destination type, where the destination 516/// type is an LLVM scalar type. 517Value *ScalarExprEmitter:: 518EmitComplexToScalarConversion(CodeGenFunction::ComplexPairTy Src, 519 QualType SrcTy, QualType DstTy) { 520 // Get the source element type. 521 SrcTy = SrcTy->getAsComplexType()->getElementType(); 522 523 // Handle conversions to bool first, they are special: comparisons against 0. 524 if (DstTy->isBooleanType()) { 525 // Complex != 0 -> (Real != 0) | (Imag != 0) 526 Src.first = EmitScalarConversion(Src.first, SrcTy, DstTy); 527 Src.second = EmitScalarConversion(Src.second, SrcTy, DstTy); 528 return Builder.CreateOr(Src.first, Src.second, "tobool"); 529 } 530 531 // C99 6.3.1.7p2: "When a value of complex type is converted to a real type, 532 // the imaginary part of the complex value is discarded and the value of the 533 // real part is converted according to the conversion rules for the 534 // corresponding real type. 535 return EmitScalarConversion(Src.first, SrcTy, DstTy); 536} 537 538 539//===----------------------------------------------------------------------===// 540// Visitor Methods 541//===----------------------------------------------------------------------===// 542 543Value *ScalarExprEmitter::VisitExpr(Expr *E) { 544 CGF.ErrorUnsupported(E, "scalar expression"); 545 if (E->getType()->isVoidType()) 546 return 0; 547 return VMContext.getUndef(CGF.ConvertType(E->getType())); 548} 549 550Value *ScalarExprEmitter::VisitShuffleVectorExpr(ShuffleVectorExpr *E) { 551 llvm::SmallVector<llvm::Constant*, 32> indices; 552 for (unsigned i = 2; i < E->getNumSubExprs(); i++) { 553 indices.push_back(cast<llvm::Constant>(CGF.EmitScalarExpr(E->getExpr(i)))); 554 } 555 Value* V1 = CGF.EmitScalarExpr(E->getExpr(0)); 556 Value* V2 = CGF.EmitScalarExpr(E->getExpr(1)); 557 Value* SV = VMContext.getConstantVector(indices.begin(), indices.size()); 558 return Builder.CreateShuffleVector(V1, V2, SV, "shuffle"); 559} 560 561Value *ScalarExprEmitter::VisitArraySubscriptExpr(ArraySubscriptExpr *E) { 562 TestAndClearIgnoreResultAssign(); 563 564 // Emit subscript expressions in rvalue context's. For most cases, this just 565 // loads the lvalue formed by the subscript expr. However, we have to be 566 // careful, because the base of a vector subscript is occasionally an rvalue, 567 // so we can't get it as an lvalue. 568 if (!E->getBase()->getType()->isVectorType()) 569 return EmitLoadOfLValue(E); 570 571 // Handle the vector case. The base must be a vector, the index must be an 572 // integer value. 573 Value *Base = Visit(E->getBase()); 574 Value *Idx = Visit(E->getIdx()); 575 bool IdxSigned = E->getIdx()->getType()->isSignedIntegerType(); 576 Idx = Builder.CreateIntCast(Idx, llvm::Type::Int32Ty, IdxSigned, 577 "vecidxcast"); 578 return Builder.CreateExtractElement(Base, Idx, "vecext"); 579} 580 581/// VisitImplicitCastExpr - Implicit casts are the same as normal casts, but 582/// also handle things like function to pointer-to-function decay, and array to 583/// pointer decay. 584Value *ScalarExprEmitter::VisitImplicitCastExpr(const ImplicitCastExpr *E) { 585 const Expr *Op = E->getSubExpr(); 586 587 // If this is due to array->pointer conversion, emit the array expression as 588 // an l-value. 589 if (Op->getType()->isArrayType()) { 590 Value *V = EmitLValue(Op).getAddress(); // Bitfields can't be arrays. 591 592 // Note that VLA pointers are always decayed, so we don't need to do 593 // anything here. 594 if (!Op->getType()->isVariableArrayType()) { 595 assert(isa<llvm::PointerType>(V->getType()) && "Expected pointer"); 596 assert(isa<llvm::ArrayType>(cast<llvm::PointerType>(V->getType()) 597 ->getElementType()) && 598 "Expected pointer to array"); 599 V = Builder.CreateStructGEP(V, 0, "arraydecay"); 600 } 601 602 // The resultant pointer type can be implicitly casted to other pointer 603 // types as well (e.g. void*) and can be implicitly converted to integer. 604 const llvm::Type *DestTy = ConvertType(E->getType()); 605 if (V->getType() != DestTy) { 606 if (isa<llvm::PointerType>(DestTy)) 607 V = Builder.CreateBitCast(V, DestTy, "ptrconv"); 608 else { 609 assert(isa<llvm::IntegerType>(DestTy) && "Unknown array decay"); 610 V = Builder.CreatePtrToInt(V, DestTy, "ptrconv"); 611 } 612 } 613 return V; 614 } 615 616 return EmitCastExpr(Op, E->getType()); 617} 618 619 620// VisitCastExpr - Emit code for an explicit or implicit cast. Implicit casts 621// have to handle a more broad range of conversions than explicit casts, as they 622// handle things like function to ptr-to-function decay etc. 623Value *ScalarExprEmitter::EmitCastExpr(const Expr *E, QualType DestTy) { 624 if (!DestTy->isVoidType()) 625 TestAndClearIgnoreResultAssign(); 626 627 // Handle cases where the source is an non-complex type. 628 629 if (!CGF.hasAggregateLLVMType(E->getType())) { 630 Value *Src = Visit(const_cast<Expr*>(E)); 631 632 // Use EmitScalarConversion to perform the conversion. 633 return EmitScalarConversion(Src, E->getType(), DestTy); 634 } 635 636 if (E->getType()->isAnyComplexType()) { 637 // Handle cases where the source is a complex type. 638 bool IgnoreImag = true; 639 bool IgnoreImagAssign = true; 640 bool IgnoreReal = IgnoreResultAssign; 641 bool IgnoreRealAssign = IgnoreResultAssign; 642 if (DestTy->isBooleanType()) 643 IgnoreImagAssign = IgnoreImag = false; 644 else if (DestTy->isVoidType()) { 645 IgnoreReal = IgnoreImag = false; 646 IgnoreRealAssign = IgnoreImagAssign = true; 647 } 648 CodeGenFunction::ComplexPairTy V 649 = CGF.EmitComplexExpr(E, IgnoreReal, IgnoreImag, IgnoreRealAssign, 650 IgnoreImagAssign); 651 return EmitComplexToScalarConversion(V, E->getType(), DestTy); 652 } 653 654 // Okay, this is a cast from an aggregate. It must be a cast to void. Just 655 // evaluate the result and return. 656 CGF.EmitAggExpr(E, 0, false, true); 657 return 0; 658} 659 660Value *ScalarExprEmitter::VisitStmtExpr(const StmtExpr *E) { 661 return CGF.EmitCompoundStmt(*E->getSubStmt(), 662 !E->getType()->isVoidType()).getScalarVal(); 663} 664 665Value *ScalarExprEmitter::VisitBlockDeclRefExpr(const BlockDeclRefExpr *E) { 666 return Builder.CreateLoad(CGF.GetAddrOfBlockDecl(E), false, "tmp"); 667} 668 669//===----------------------------------------------------------------------===// 670// Unary Operators 671//===----------------------------------------------------------------------===// 672 673Value *ScalarExprEmitter::VisitPrePostIncDec(const UnaryOperator *E, 674 bool isInc, bool isPre) { 675 LValue LV = EmitLValue(E->getSubExpr()); 676 QualType ValTy = E->getSubExpr()->getType(); 677 Value *InVal = CGF.EmitLoadOfLValue(LV, ValTy).getScalarVal(); 678 679 int AmountVal = isInc ? 1 : -1; 680 681 if (ValTy->isPointerType() && 682 ValTy->getAs<PointerType>()->isVariableArrayType()) { 683 // The amount of the addition/subtraction needs to account for the VLA size 684 CGF.ErrorUnsupported(E, "VLA pointer inc/dec"); 685 } 686 687 Value *NextVal; 688 if (const llvm::PointerType *PT = 689 dyn_cast<llvm::PointerType>(InVal->getType())) { 690 llvm::Constant *Inc = 691 VMContext.getConstantInt(llvm::Type::Int32Ty, AmountVal); 692 if (!isa<llvm::FunctionType>(PT->getElementType())) { 693 QualType PTEE = ValTy->getPointeeType(); 694 if (const ObjCInterfaceType *OIT = 695 dyn_cast<ObjCInterfaceType>(PTEE)) { 696 // Handle interface types, which are not represented with a concrete type. 697 int size = CGF.getContext().getTypeSize(OIT) / 8; 698 if (!isInc) 699 size = -size; 700 Inc = VMContext.getConstantInt(Inc->getType(), size); 701 const llvm::Type *i8Ty = 702 VMContext.getPointerTypeUnqual(llvm::Type::Int8Ty); 703 InVal = Builder.CreateBitCast(InVal, i8Ty); 704 NextVal = Builder.CreateGEP(InVal, Inc, "add.ptr"); 705 llvm::Value *lhs = LV.getAddress(); 706 lhs = Builder.CreateBitCast(lhs, VMContext.getPointerTypeUnqual(i8Ty)); 707 LV = LValue::MakeAddr(lhs, ValTy.getCVRQualifiers(), 708 CGF.getContext().getObjCGCAttrKind(ValTy)); 709 } 710 else 711 NextVal = Builder.CreateGEP(InVal, Inc, "ptrincdec"); 712 } else { 713 const llvm::Type *i8Ty = 714 VMContext.getPointerTypeUnqual(llvm::Type::Int8Ty); 715 NextVal = Builder.CreateBitCast(InVal, i8Ty, "tmp"); 716 NextVal = Builder.CreateGEP(NextVal, Inc, "ptrincdec"); 717 NextVal = Builder.CreateBitCast(NextVal, InVal->getType()); 718 } 719 } else if (InVal->getType() == llvm::Type::Int1Ty && isInc) { 720 // Bool++ is an interesting case, due to promotion rules, we get: 721 // Bool++ -> Bool = Bool+1 -> Bool = (int)Bool+1 -> 722 // Bool = ((int)Bool+1) != 0 723 // An interesting aspect of this is that increment is always true. 724 // Decrement does not have this property. 725 NextVal = VMContext.getConstantIntTrue(); 726 } else if (isa<llvm::IntegerType>(InVal->getType())) { 727 NextVal = VMContext.getConstantInt(InVal->getType(), AmountVal); 728 NextVal = Builder.CreateAdd(InVal, NextVal, isInc ? "inc" : "dec"); 729 } else { 730 // Add the inc/dec to the real part. 731 if (InVal->getType() == llvm::Type::FloatTy) 732 NextVal = 733 VMContext.getConstantFP(llvm::APFloat(static_cast<float>(AmountVal))); 734 else if (InVal->getType() == llvm::Type::DoubleTy) 735 NextVal = 736 VMContext.getConstantFP(llvm::APFloat(static_cast<double>(AmountVal))); 737 else { 738 llvm::APFloat F(static_cast<float>(AmountVal)); 739 bool ignored; 740 F.convert(CGF.Target.getLongDoubleFormat(), llvm::APFloat::rmTowardZero, 741 &ignored); 742 NextVal = VMContext.getConstantFP(F); 743 } 744 NextVal = Builder.CreateFAdd(InVal, NextVal, isInc ? "inc" : "dec"); 745 } 746 747 // Store the updated result through the lvalue. 748 if (LV.isBitfield()) 749 CGF.EmitStoreThroughBitfieldLValue(RValue::get(NextVal), LV, ValTy, 750 &NextVal); 751 else 752 CGF.EmitStoreThroughLValue(RValue::get(NextVal), LV, ValTy); 753 754 // If this is a postinc, return the value read from memory, otherwise use the 755 // updated value. 756 return isPre ? NextVal : InVal; 757} 758 759 760Value *ScalarExprEmitter::VisitUnaryMinus(const UnaryOperator *E) { 761 TestAndClearIgnoreResultAssign(); 762 Value *Op = Visit(E->getSubExpr()); 763 if (Op->getType()->isFPOrFPVector()) 764 return Builder.CreateFNeg(Op, "neg"); 765 return Builder.CreateNeg(Op, "neg"); 766} 767 768Value *ScalarExprEmitter::VisitUnaryNot(const UnaryOperator *E) { 769 TestAndClearIgnoreResultAssign(); 770 Value *Op = Visit(E->getSubExpr()); 771 return Builder.CreateNot(Op, "neg"); 772} 773 774Value *ScalarExprEmitter::VisitUnaryLNot(const UnaryOperator *E) { 775 // Compare operand to zero. 776 Value *BoolVal = CGF.EvaluateExprAsBool(E->getSubExpr()); 777 778 // Invert value. 779 // TODO: Could dynamically modify easy computations here. For example, if 780 // the operand is an icmp ne, turn into icmp eq. 781 BoolVal = Builder.CreateNot(BoolVal, "lnot"); 782 783 // ZExt result to the expr type. 784 return Builder.CreateZExt(BoolVal, ConvertType(E->getType()), "lnot.ext"); 785} 786 787/// VisitSizeOfAlignOfExpr - Return the size or alignment of the type of 788/// argument of the sizeof expression as an integer. 789Value * 790ScalarExprEmitter::VisitSizeOfAlignOfExpr(const SizeOfAlignOfExpr *E) { 791 QualType TypeToSize = E->getTypeOfArgument(); 792 if (E->isSizeOf()) { 793 if (const VariableArrayType *VAT = 794 CGF.getContext().getAsVariableArrayType(TypeToSize)) { 795 if (E->isArgumentType()) { 796 // sizeof(type) - make sure to emit the VLA size. 797 CGF.EmitVLASize(TypeToSize); 798 } else { 799 // C99 6.5.3.4p2: If the argument is an expression of type 800 // VLA, it is evaluated. 801 CGF.EmitAnyExpr(E->getArgumentExpr()); 802 } 803 804 return CGF.GetVLASize(VAT); 805 } 806 } 807 808 // If this isn't sizeof(vla), the result must be constant; use the 809 // constant folding logic so we don't have to duplicate it here. 810 Expr::EvalResult Result; 811 E->Evaluate(Result, CGF.getContext()); 812 return VMContext.getConstantInt(Result.Val.getInt()); 813} 814 815Value *ScalarExprEmitter::VisitUnaryReal(const UnaryOperator *E) { 816 Expr *Op = E->getSubExpr(); 817 if (Op->getType()->isAnyComplexType()) 818 return CGF.EmitComplexExpr(Op, false, true, false, true).first; 819 return Visit(Op); 820} 821Value *ScalarExprEmitter::VisitUnaryImag(const UnaryOperator *E) { 822 Expr *Op = E->getSubExpr(); 823 if (Op->getType()->isAnyComplexType()) 824 return CGF.EmitComplexExpr(Op, true, false, true, false).second; 825 826 // __imag on a scalar returns zero. Emit the subexpr to ensure side 827 // effects are evaluated, but not the actual value. 828 if (E->isLvalue(CGF.getContext()) == Expr::LV_Valid) 829 CGF.EmitLValue(Op); 830 else 831 CGF.EmitScalarExpr(Op, true); 832 return VMContext.getNullValue(ConvertType(E->getType())); 833} 834 835Value *ScalarExprEmitter::VisitUnaryOffsetOf(const UnaryOperator *E) 836{ 837 Value* ResultAsPtr = EmitLValue(E->getSubExpr()).getAddress(); 838 const llvm::Type* ResultType = ConvertType(E->getType()); 839 return Builder.CreatePtrToInt(ResultAsPtr, ResultType, "offsetof"); 840} 841 842//===----------------------------------------------------------------------===// 843// Binary Operators 844//===----------------------------------------------------------------------===// 845 846BinOpInfo ScalarExprEmitter::EmitBinOps(const BinaryOperator *E) { 847 TestAndClearIgnoreResultAssign(); 848 BinOpInfo Result; 849 Result.LHS = Visit(E->getLHS()); 850 Result.RHS = Visit(E->getRHS()); 851 Result.Ty = E->getType(); 852 Result.E = E; 853 return Result; 854} 855 856Value *ScalarExprEmitter::EmitCompoundAssign(const CompoundAssignOperator *E, 857 Value *(ScalarExprEmitter::*Func)(const BinOpInfo &)) { 858 bool Ignore = TestAndClearIgnoreResultAssign(); 859 QualType LHSTy = E->getLHS()->getType(), RHSTy = E->getRHS()->getType(); 860 861 BinOpInfo OpInfo; 862 863 if (E->getComputationResultType()->isAnyComplexType()) { 864 // This needs to go through the complex expression emitter, but 865 // it's a tad complicated to do that... I'm leaving it out for now. 866 // (Note that we do actually need the imaginary part of the RHS for 867 // multiplication and division.) 868 CGF.ErrorUnsupported(E, "complex compound assignment"); 869 return VMContext.getUndef(CGF.ConvertType(E->getType())); 870 } 871 872 // Emit the RHS first. __block variables need to have the rhs evaluated 873 // first, plus this should improve codegen a little. 874 OpInfo.RHS = Visit(E->getRHS()); 875 OpInfo.Ty = E->getComputationResultType(); 876 OpInfo.E = E; 877 // Load/convert the LHS. 878 LValue LHSLV = EmitLValue(E->getLHS()); 879 OpInfo.LHS = EmitLoadOfLValue(LHSLV, LHSTy); 880 OpInfo.LHS = EmitScalarConversion(OpInfo.LHS, LHSTy, 881 E->getComputationLHSType()); 882 883 // Expand the binary operator. 884 Value *Result = (this->*Func)(OpInfo); 885 886 // Convert the result back to the LHS type. 887 Result = EmitScalarConversion(Result, E->getComputationResultType(), LHSTy); 888 889 // Store the result value into the LHS lvalue. Bit-fields are 890 // handled specially because the result is altered by the store, 891 // i.e., [C99 6.5.16p1] 'An assignment expression has the value of 892 // the left operand after the assignment...'. 893 if (LHSLV.isBitfield()) { 894 if (!LHSLV.isVolatileQualified()) { 895 CGF.EmitStoreThroughBitfieldLValue(RValue::get(Result), LHSLV, LHSTy, 896 &Result); 897 return Result; 898 } else 899 CGF.EmitStoreThroughBitfieldLValue(RValue::get(Result), LHSLV, LHSTy); 900 } else 901 CGF.EmitStoreThroughLValue(RValue::get(Result), LHSLV, LHSTy); 902 if (Ignore) 903 return 0; 904 return EmitLoadOfLValue(LHSLV, E->getType()); 905} 906 907 908Value *ScalarExprEmitter::EmitDiv(const BinOpInfo &Ops) { 909 if (Ops.LHS->getType()->isFPOrFPVector()) 910 return Builder.CreateFDiv(Ops.LHS, Ops.RHS, "div"); 911 else if (Ops.Ty->isUnsignedIntegerType()) 912 return Builder.CreateUDiv(Ops.LHS, Ops.RHS, "div"); 913 else 914 return Builder.CreateSDiv(Ops.LHS, Ops.RHS, "div"); 915} 916 917Value *ScalarExprEmitter::EmitRem(const BinOpInfo &Ops) { 918 // Rem in C can't be a floating point type: C99 6.5.5p2. 919 if (Ops.Ty->isUnsignedIntegerType()) 920 return Builder.CreateURem(Ops.LHS, Ops.RHS, "rem"); 921 else 922 return Builder.CreateSRem(Ops.LHS, Ops.RHS, "rem"); 923} 924 925Value *ScalarExprEmitter::EmitOverflowCheckedBinOp(const BinOpInfo &Ops) { 926 unsigned IID; 927 unsigned OpID = 0; 928 929 switch (Ops.E->getOpcode()) { 930 case BinaryOperator::Add: 931 case BinaryOperator::AddAssign: 932 OpID = 1; 933 IID = llvm::Intrinsic::sadd_with_overflow; 934 break; 935 case BinaryOperator::Sub: 936 case BinaryOperator::SubAssign: 937 OpID = 2; 938 IID = llvm::Intrinsic::ssub_with_overflow; 939 break; 940 case BinaryOperator::Mul: 941 case BinaryOperator::MulAssign: 942 OpID = 3; 943 IID = llvm::Intrinsic::smul_with_overflow; 944 break; 945 default: 946 assert(false && "Unsupported operation for overflow detection"); 947 IID = 0; 948 } 949 OpID <<= 1; 950 OpID |= 1; 951 952 const llvm::Type *opTy = CGF.CGM.getTypes().ConvertType(Ops.Ty); 953 954 llvm::Function *intrinsic = CGF.CGM.getIntrinsic(IID, &opTy, 1); 955 956 Value *resultAndOverflow = Builder.CreateCall2(intrinsic, Ops.LHS, Ops.RHS); 957 Value *result = Builder.CreateExtractValue(resultAndOverflow, 0); 958 Value *overflow = Builder.CreateExtractValue(resultAndOverflow, 1); 959 960 // Branch in case of overflow. 961 llvm::BasicBlock *initialBB = Builder.GetInsertBlock(); 962 llvm::BasicBlock *overflowBB = 963 CGF.createBasicBlock("overflow", CGF.CurFn); 964 llvm::BasicBlock *continueBB = 965 CGF.createBasicBlock("overflow.continue", CGF.CurFn); 966 967 Builder.CreateCondBr(overflow, overflowBB, continueBB); 968 969 // Handle overflow 970 971 Builder.SetInsertPoint(overflowBB); 972 973 // Handler is: 974 // long long *__overflow_handler)(long long a, long long b, char op, 975 // char width) 976 std::vector<const llvm::Type*> handerArgTypes; 977 handerArgTypes.push_back(llvm::Type::Int64Ty); 978 handerArgTypes.push_back(llvm::Type::Int64Ty); 979 handerArgTypes.push_back(llvm::Type::Int8Ty); 980 handerArgTypes.push_back(llvm::Type::Int8Ty); 981 llvm::FunctionType *handlerTy = VMContext.getFunctionType(llvm::Type::Int64Ty, 982 handerArgTypes, false); 983 llvm::Value *handlerFunction = 984 CGF.CGM.getModule().getOrInsertGlobal("__overflow_handler", 985 VMContext.getPointerTypeUnqual(handlerTy)); 986 handlerFunction = Builder.CreateLoad(handlerFunction); 987 988 llvm::Value *handlerResult = Builder.CreateCall4(handlerFunction, 989 Builder.CreateSExt(Ops.LHS, llvm::Type::Int64Ty), 990 Builder.CreateSExt(Ops.RHS, llvm::Type::Int64Ty), 991 VMContext.getConstantInt(llvm::Type::Int8Ty, OpID), 992 VMContext.getConstantInt(llvm::Type::Int8Ty, 993 cast<llvm::IntegerType>(opTy)->getBitWidth())); 994 995 handlerResult = Builder.CreateTrunc(handlerResult, opTy); 996 997 Builder.CreateBr(continueBB); 998 999 // Set up the continuation 1000 Builder.SetInsertPoint(continueBB); 1001 // Get the correct result 1002 llvm::PHINode *phi = Builder.CreatePHI(opTy); 1003 phi->reserveOperandSpace(2); 1004 phi->addIncoming(result, initialBB); 1005 phi->addIncoming(handlerResult, overflowBB); 1006 1007 return phi; 1008} 1009 1010Value *ScalarExprEmitter::EmitAdd(const BinOpInfo &Ops) { 1011 if (!Ops.Ty->isAnyPointerType()) { 1012 if (CGF.getContext().getLangOptions().OverflowChecking && 1013 Ops.Ty->isSignedIntegerType()) 1014 return EmitOverflowCheckedBinOp(Ops); 1015 1016 if (Ops.LHS->getType()->isFPOrFPVector()) 1017 return Builder.CreateFAdd(Ops.LHS, Ops.RHS, "add"); 1018 1019 return Builder.CreateAdd(Ops.LHS, Ops.RHS, "add"); 1020 } 1021 1022 if (Ops.Ty->isPointerType() && 1023 Ops.Ty->getAs<PointerType>()->isVariableArrayType()) { 1024 // The amount of the addition needs to account for the VLA size 1025 CGF.ErrorUnsupported(Ops.E, "VLA pointer addition"); 1026 } 1027 Value *Ptr, *Idx; 1028 Expr *IdxExp; 1029 const PointerType *PT = Ops.E->getLHS()->getType()->getAs<PointerType>(); 1030 const ObjCObjectPointerType *OPT = 1031 Ops.E->getLHS()->getType()->getAsObjCObjectPointerType(); 1032 if (PT || OPT) { 1033 Ptr = Ops.LHS; 1034 Idx = Ops.RHS; 1035 IdxExp = Ops.E->getRHS(); 1036 } else { // int + pointer 1037 PT = Ops.E->getRHS()->getType()->getAs<PointerType>(); 1038 OPT = Ops.E->getRHS()->getType()->getAsObjCObjectPointerType(); 1039 assert((PT || OPT) && "Invalid add expr"); 1040 Ptr = Ops.RHS; 1041 Idx = Ops.LHS; 1042 IdxExp = Ops.E->getLHS(); 1043 } 1044 1045 unsigned Width = cast<llvm::IntegerType>(Idx->getType())->getBitWidth(); 1046 if (Width < CGF.LLVMPointerWidth) { 1047 // Zero or sign extend the pointer value based on whether the index is 1048 // signed or not. 1049 const llvm::Type *IdxType = VMContext.getIntegerType(CGF.LLVMPointerWidth); 1050 if (IdxExp->getType()->isSignedIntegerType()) 1051 Idx = Builder.CreateSExt(Idx, IdxType, "idx.ext"); 1052 else 1053 Idx = Builder.CreateZExt(Idx, IdxType, "idx.ext"); 1054 } 1055 const QualType ElementType = PT ? PT->getPointeeType() : OPT->getPointeeType(); 1056 // Handle interface types, which are not represented with a concrete 1057 // type. 1058 if (const ObjCInterfaceType *OIT = dyn_cast<ObjCInterfaceType>(ElementType)) { 1059 llvm::Value *InterfaceSize = 1060 VMContext.getConstantInt(Idx->getType(), 1061 CGF.getContext().getTypeSize(OIT) / 8); 1062 Idx = Builder.CreateMul(Idx, InterfaceSize); 1063 const llvm::Type *i8Ty = VMContext.getPointerTypeUnqual(llvm::Type::Int8Ty); 1064 Value *Casted = Builder.CreateBitCast(Ptr, i8Ty); 1065 Value *Res = Builder.CreateGEP(Casted, Idx, "add.ptr"); 1066 return Builder.CreateBitCast(Res, Ptr->getType()); 1067 } 1068 1069 // Explicitly handle GNU void* and function pointer arithmetic 1070 // extensions. The GNU void* casts amount to no-ops since our void* 1071 // type is i8*, but this is future proof. 1072 if (ElementType->isVoidType() || ElementType->isFunctionType()) { 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 return Builder.CreateGEP(Ptr, Idx, "add.ptr"); 1080} 1081 1082Value *ScalarExprEmitter::EmitSub(const BinOpInfo &Ops) { 1083 if (!isa<llvm::PointerType>(Ops.LHS->getType())) { 1084 if (CGF.getContext().getLangOptions().OverflowChecking 1085 && Ops.Ty->isSignedIntegerType()) 1086 return EmitOverflowCheckedBinOp(Ops); 1087 1088 if (Ops.LHS->getType()->isFPOrFPVector()) 1089 return Builder.CreateFSub(Ops.LHS, Ops.RHS, "sub"); 1090 return Builder.CreateSub(Ops.LHS, Ops.RHS, "sub"); 1091 } 1092 1093 if (Ops.E->getLHS()->getType()->isPointerType() && 1094 Ops.E->getLHS()->getType()->getAs<PointerType>()->isVariableArrayType()) { 1095 // The amount of the addition needs to account for the VLA size for 1096 // ptr-int 1097 // The amount of the division needs to account for the VLA size for 1098 // ptr-ptr. 1099 CGF.ErrorUnsupported(Ops.E, "VLA pointer subtraction"); 1100 } 1101 1102 const QualType LHSType = Ops.E->getLHS()->getType(); 1103 const QualType LHSElementType = LHSType->getPointeeType(); 1104 if (!isa<llvm::PointerType>(Ops.RHS->getType())) { 1105 // pointer - int 1106 Value *Idx = Ops.RHS; 1107 unsigned Width = cast<llvm::IntegerType>(Idx->getType())->getBitWidth(); 1108 if (Width < CGF.LLVMPointerWidth) { 1109 // Zero or sign extend the pointer value based on whether the index is 1110 // signed or not. 1111 const llvm::Type *IdxType = 1112 VMContext.getIntegerType(CGF.LLVMPointerWidth); 1113 if (Ops.E->getRHS()->getType()->isSignedIntegerType()) 1114 Idx = Builder.CreateSExt(Idx, IdxType, "idx.ext"); 1115 else 1116 Idx = Builder.CreateZExt(Idx, IdxType, "idx.ext"); 1117 } 1118 Idx = Builder.CreateNeg(Idx, "sub.ptr.neg"); 1119 1120 // Handle interface types, which are not represented with a concrete 1121 // type. 1122 if (const ObjCInterfaceType *OIT = 1123 dyn_cast<ObjCInterfaceType>(LHSElementType)) { 1124 llvm::Value *InterfaceSize = 1125 VMContext.getConstantInt(Idx->getType(), 1126 CGF.getContext().getTypeSize(OIT) / 8); 1127 Idx = Builder.CreateMul(Idx, InterfaceSize); 1128 const llvm::Type *i8Ty = 1129 VMContext.getPointerTypeUnqual(llvm::Type::Int8Ty); 1130 Value *LHSCasted = Builder.CreateBitCast(Ops.LHS, i8Ty); 1131 Value *Res = Builder.CreateGEP(LHSCasted, Idx, "add.ptr"); 1132 return Builder.CreateBitCast(Res, Ops.LHS->getType()); 1133 } 1134 1135 // Explicitly handle GNU void* and function pointer arithmetic 1136 // extensions. The GNU void* casts amount to no-ops since our 1137 // void* type is i8*, but this is future proof. 1138 if (LHSElementType->isVoidType() || LHSElementType->isFunctionType()) { 1139 const llvm::Type *i8Ty = 1140 VMContext.getPointerTypeUnqual(llvm::Type::Int8Ty); 1141 Value *LHSCasted = Builder.CreateBitCast(Ops.LHS, i8Ty); 1142 Value *Res = Builder.CreateGEP(LHSCasted, Idx, "sub.ptr"); 1143 return Builder.CreateBitCast(Res, Ops.LHS->getType()); 1144 } 1145 1146 return Builder.CreateGEP(Ops.LHS, Idx, "sub.ptr"); 1147 } else { 1148 // pointer - pointer 1149 Value *LHS = Ops.LHS; 1150 Value *RHS = Ops.RHS; 1151 1152 uint64_t ElementSize; 1153 1154 // Handle GCC extension for pointer arithmetic on void* and function pointer 1155 // types. 1156 if (LHSElementType->isVoidType() || LHSElementType->isFunctionType()) { 1157 ElementSize = 1; 1158 } else { 1159 ElementSize = CGF.getContext().getTypeSize(LHSElementType) / 8; 1160 } 1161 1162 const llvm::Type *ResultType = ConvertType(Ops.Ty); 1163 LHS = Builder.CreatePtrToInt(LHS, ResultType, "sub.ptr.lhs.cast"); 1164 RHS = Builder.CreatePtrToInt(RHS, ResultType, "sub.ptr.rhs.cast"); 1165 Value *BytesBetween = Builder.CreateSub(LHS, RHS, "sub.ptr.sub"); 1166 1167 // Optimize out the shift for element size of 1. 1168 if (ElementSize == 1) 1169 return BytesBetween; 1170 1171 // HACK: LLVM doesn't have an divide instruction that 'knows' there is no 1172 // remainder. As such, we handle common power-of-two cases here to generate 1173 // better code. See PR2247. 1174 if (llvm::isPowerOf2_64(ElementSize)) { 1175 Value *ShAmt = 1176 VMContext.getConstantInt(ResultType, llvm::Log2_64(ElementSize)); 1177 return Builder.CreateAShr(BytesBetween, ShAmt, "sub.ptr.shr"); 1178 } 1179 1180 // Otherwise, do a full sdiv. 1181 Value *BytesPerElt = VMContext.getConstantInt(ResultType, ElementSize); 1182 return Builder.CreateSDiv(BytesBetween, BytesPerElt, "sub.ptr.div"); 1183 } 1184} 1185 1186Value *ScalarExprEmitter::EmitShl(const BinOpInfo &Ops) { 1187 // LLVM requires the LHS and RHS to be the same type: promote or truncate the 1188 // RHS to the same size as the LHS. 1189 Value *RHS = Ops.RHS; 1190 if (Ops.LHS->getType() != RHS->getType()) 1191 RHS = Builder.CreateIntCast(RHS, Ops.LHS->getType(), false, "sh_prom"); 1192 1193 return Builder.CreateShl(Ops.LHS, RHS, "shl"); 1194} 1195 1196Value *ScalarExprEmitter::EmitShr(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 if (Ops.Ty->isUnsignedIntegerType()) 1204 return Builder.CreateLShr(Ops.LHS, RHS, "shr"); 1205 return Builder.CreateAShr(Ops.LHS, RHS, "shr"); 1206} 1207 1208Value *ScalarExprEmitter::EmitCompare(const BinaryOperator *E,unsigned UICmpOpc, 1209 unsigned SICmpOpc, unsigned FCmpOpc) { 1210 TestAndClearIgnoreResultAssign(); 1211 Value *Result; 1212 QualType LHSTy = E->getLHS()->getType(); 1213 if (!LHSTy->isAnyComplexType()) { 1214 Value *LHS = Visit(E->getLHS()); 1215 Value *RHS = Visit(E->getRHS()); 1216 1217 if (LHS->getType()->isFloatingPoint()) { 1218 Result = Builder.CreateFCmp((llvm::CmpInst::Predicate)FCmpOpc, 1219 LHS, RHS, "cmp"); 1220 } else if (LHSTy->isSignedIntegerType()) { 1221 Result = Builder.CreateICmp((llvm::ICmpInst::Predicate)SICmpOpc, 1222 LHS, RHS, "cmp"); 1223 } else { 1224 // Unsigned integers and pointers. 1225 Result = Builder.CreateICmp((llvm::ICmpInst::Predicate)UICmpOpc, 1226 LHS, RHS, "cmp"); 1227 } 1228 1229 // If this is a vector comparison, sign extend the result to the appropriate 1230 // vector integer type and return it (don't convert to bool). 1231 if (LHSTy->isVectorType()) 1232 return Builder.CreateSExt(Result, ConvertType(E->getType()), "sext"); 1233 1234 } else { 1235 // Complex Comparison: can only be an equality comparison. 1236 CodeGenFunction::ComplexPairTy LHS = CGF.EmitComplexExpr(E->getLHS()); 1237 CodeGenFunction::ComplexPairTy RHS = CGF.EmitComplexExpr(E->getRHS()); 1238 1239 QualType CETy = LHSTy->getAsComplexType()->getElementType(); 1240 1241 Value *ResultR, *ResultI; 1242 if (CETy->isRealFloatingType()) { 1243 ResultR = Builder.CreateFCmp((llvm::FCmpInst::Predicate)FCmpOpc, 1244 LHS.first, RHS.first, "cmp.r"); 1245 ResultI = Builder.CreateFCmp((llvm::FCmpInst::Predicate)FCmpOpc, 1246 LHS.second, RHS.second, "cmp.i"); 1247 } else { 1248 // Complex comparisons can only be equality comparisons. As such, signed 1249 // and unsigned opcodes are the same. 1250 ResultR = Builder.CreateICmp((llvm::ICmpInst::Predicate)UICmpOpc, 1251 LHS.first, RHS.first, "cmp.r"); 1252 ResultI = Builder.CreateICmp((llvm::ICmpInst::Predicate)UICmpOpc, 1253 LHS.second, RHS.second, "cmp.i"); 1254 } 1255 1256 if (E->getOpcode() == BinaryOperator::EQ) { 1257 Result = Builder.CreateAnd(ResultR, ResultI, "and.ri"); 1258 } else { 1259 assert(E->getOpcode() == BinaryOperator::NE && 1260 "Complex comparison other than == or != ?"); 1261 Result = Builder.CreateOr(ResultR, ResultI, "or.ri"); 1262 } 1263 } 1264 1265 return EmitScalarConversion(Result, CGF.getContext().BoolTy, E->getType()); 1266} 1267 1268Value *ScalarExprEmitter::VisitBinAssign(const BinaryOperator *E) { 1269 bool Ignore = TestAndClearIgnoreResultAssign(); 1270 1271 // __block variables need to have the rhs evaluated first, plus this should 1272 // improve codegen just a little. 1273 Value *RHS = Visit(E->getRHS()); 1274 LValue LHS = EmitLValue(E->getLHS()); 1275 1276 // Store the value into the LHS. Bit-fields are handled specially 1277 // because the result is altered by the store, i.e., [C99 6.5.16p1] 1278 // 'An assignment expression has the value of the left operand after 1279 // the assignment...'. 1280 if (LHS.isBitfield()) { 1281 if (!LHS.isVolatileQualified()) { 1282 CGF.EmitStoreThroughBitfieldLValue(RValue::get(RHS), LHS, E->getType(), 1283 &RHS); 1284 return RHS; 1285 } else 1286 CGF.EmitStoreThroughBitfieldLValue(RValue::get(RHS), LHS, E->getType()); 1287 } else 1288 CGF.EmitStoreThroughLValue(RValue::get(RHS), LHS, E->getType()); 1289 if (Ignore) 1290 return 0; 1291 return EmitLoadOfLValue(LHS, E->getType()); 1292} 1293 1294Value *ScalarExprEmitter::VisitBinLAnd(const BinaryOperator *E) { 1295 // If we have 0 && RHS, see if we can elide RHS, if so, just return 0. 1296 // If we have 1 && X, just emit X without inserting the control flow. 1297 if (int Cond = CGF.ConstantFoldsToSimpleInteger(E->getLHS())) { 1298 if (Cond == 1) { // If we have 1 && X, just emit X. 1299 Value *RHSCond = CGF.EvaluateExprAsBool(E->getRHS()); 1300 // ZExt result to int. 1301 return Builder.CreateZExt(RHSCond, CGF.LLVMIntTy, "land.ext"); 1302 } 1303 1304 // 0 && RHS: If it is safe, just elide the RHS, and return 0. 1305 if (!CGF.ContainsLabel(E->getRHS())) 1306 return VMContext.getNullValue(CGF.LLVMIntTy); 1307 } 1308 1309 llvm::BasicBlock *ContBlock = CGF.createBasicBlock("land.end"); 1310 llvm::BasicBlock *RHSBlock = CGF.createBasicBlock("land.rhs"); 1311 1312 // Branch on the LHS first. If it is false, go to the failure (cont) block. 1313 CGF.EmitBranchOnBoolExpr(E->getLHS(), RHSBlock, ContBlock); 1314 1315 // Any edges into the ContBlock are now from an (indeterminate number of) 1316 // edges from this first condition. All of these values will be false. Start 1317 // setting up the PHI node in the Cont Block for this. 1318 llvm::PHINode *PN = llvm::PHINode::Create(llvm::Type::Int1Ty, "", ContBlock); 1319 PN->reserveOperandSpace(2); // Normal case, two inputs. 1320 for (llvm::pred_iterator PI = pred_begin(ContBlock), PE = pred_end(ContBlock); 1321 PI != PE; ++PI) 1322 PN->addIncoming(VMContext.getConstantIntFalse(), *PI); 1323 1324 CGF.PushConditionalTempDestruction(); 1325 CGF.EmitBlock(RHSBlock); 1326 Value *RHSCond = CGF.EvaluateExprAsBool(E->getRHS()); 1327 CGF.PopConditionalTempDestruction(); 1328 1329 // Reaquire the RHS block, as there may be subblocks inserted. 1330 RHSBlock = Builder.GetInsertBlock(); 1331 1332 // Emit an unconditional branch from this block to ContBlock. Insert an entry 1333 // into the phi node for the edge with the value of RHSCond. 1334 CGF.EmitBlock(ContBlock); 1335 PN->addIncoming(RHSCond, RHSBlock); 1336 1337 // ZExt result to int. 1338 return Builder.CreateZExt(PN, CGF.LLVMIntTy, "land.ext"); 1339} 1340 1341Value *ScalarExprEmitter::VisitBinLOr(const BinaryOperator *E) { 1342 // If we have 1 || RHS, see if we can elide RHS, if so, just return 1. 1343 // If we have 0 || X, just emit X without inserting the control flow. 1344 if (int Cond = CGF.ConstantFoldsToSimpleInteger(E->getLHS())) { 1345 if (Cond == -1) { // If we have 0 || X, just emit X. 1346 Value *RHSCond = CGF.EvaluateExprAsBool(E->getRHS()); 1347 // ZExt result to int. 1348 return Builder.CreateZExt(RHSCond, CGF.LLVMIntTy, "lor.ext"); 1349 } 1350 1351 // 1 || RHS: If it is safe, just elide the RHS, and return 1. 1352 if (!CGF.ContainsLabel(E->getRHS())) 1353 return VMContext.getConstantInt(CGF.LLVMIntTy, 1); 1354 } 1355 1356 llvm::BasicBlock *ContBlock = CGF.createBasicBlock("lor.end"); 1357 llvm::BasicBlock *RHSBlock = CGF.createBasicBlock("lor.rhs"); 1358 1359 // Branch on the LHS first. If it is true, go to the success (cont) block. 1360 CGF.EmitBranchOnBoolExpr(E->getLHS(), ContBlock, RHSBlock); 1361 1362 // Any edges into the ContBlock are now from an (indeterminate number of) 1363 // edges from this first condition. All of these values will be true. Start 1364 // setting up the PHI node in the Cont Block for this. 1365 llvm::PHINode *PN = llvm::PHINode::Create(llvm::Type::Int1Ty, "", ContBlock); 1366 PN->reserveOperandSpace(2); // Normal case, two inputs. 1367 for (llvm::pred_iterator PI = pred_begin(ContBlock), PE = pred_end(ContBlock); 1368 PI != PE; ++PI) 1369 PN->addIncoming(VMContext.getConstantIntTrue(), *PI); 1370 1371 CGF.PushConditionalTempDestruction(); 1372 1373 // Emit the RHS condition as a bool value. 1374 CGF.EmitBlock(RHSBlock); 1375 Value *RHSCond = CGF.EvaluateExprAsBool(E->getRHS()); 1376 1377 CGF.PopConditionalTempDestruction(); 1378 1379 // Reaquire the RHS block, as there may be subblocks inserted. 1380 RHSBlock = Builder.GetInsertBlock(); 1381 1382 // Emit an unconditional branch from this block to ContBlock. Insert an entry 1383 // into the phi node for the edge with the value of RHSCond. 1384 CGF.EmitBlock(ContBlock); 1385 PN->addIncoming(RHSCond, RHSBlock); 1386 1387 // ZExt result to int. 1388 return Builder.CreateZExt(PN, CGF.LLVMIntTy, "lor.ext"); 1389} 1390 1391Value *ScalarExprEmitter::VisitBinComma(const BinaryOperator *E) { 1392 CGF.EmitStmt(E->getLHS()); 1393 CGF.EnsureInsertPoint(); 1394 return Visit(E->getRHS()); 1395} 1396 1397//===----------------------------------------------------------------------===// 1398// Other Operators 1399//===----------------------------------------------------------------------===// 1400 1401/// isCheapEnoughToEvaluateUnconditionally - Return true if the specified 1402/// expression is cheap enough and side-effect-free enough to evaluate 1403/// unconditionally instead of conditionally. This is used to convert control 1404/// flow into selects in some cases. 1405static bool isCheapEnoughToEvaluateUnconditionally(const Expr *E) { 1406 if (const ParenExpr *PE = dyn_cast<ParenExpr>(E)) 1407 return isCheapEnoughToEvaluateUnconditionally(PE->getSubExpr()); 1408 1409 // TODO: Allow anything we can constant fold to an integer or fp constant. 1410 if (isa<IntegerLiteral>(E) || isa<CharacterLiteral>(E) || 1411 isa<FloatingLiteral>(E)) 1412 return true; 1413 1414 // Non-volatile automatic variables too, to get "cond ? X : Y" where 1415 // X and Y are local variables. 1416 if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(E)) 1417 if (const VarDecl *VD = dyn_cast<VarDecl>(DRE->getDecl())) 1418 if (VD->hasLocalStorage() && !VD->getType().isVolatileQualified()) 1419 return true; 1420 1421 return false; 1422} 1423 1424 1425Value *ScalarExprEmitter:: 1426VisitConditionalOperator(const ConditionalOperator *E) { 1427 TestAndClearIgnoreResultAssign(); 1428 // If the condition constant folds and can be elided, try to avoid emitting 1429 // the condition and the dead arm. 1430 if (int Cond = CGF.ConstantFoldsToSimpleInteger(E->getCond())){ 1431 Expr *Live = E->getLHS(), *Dead = E->getRHS(); 1432 if (Cond == -1) 1433 std::swap(Live, Dead); 1434 1435 // If the dead side doesn't have labels we need, and if the Live side isn't 1436 // the gnu missing ?: extension (which we could handle, but don't bother 1437 // to), just emit the Live part. 1438 if ((!Dead || !CGF.ContainsLabel(Dead)) && // No labels in dead part 1439 Live) // Live part isn't missing. 1440 return Visit(Live); 1441 } 1442 1443 1444 // If this is a really simple expression (like x ? 4 : 5), emit this as a 1445 // select instead of as control flow. We can only do this if it is cheap and 1446 // safe to evaluate the LHS and RHS unconditionally. 1447 if (E->getLHS() && isCheapEnoughToEvaluateUnconditionally(E->getLHS()) && 1448 isCheapEnoughToEvaluateUnconditionally(E->getRHS())) { 1449 llvm::Value *CondV = CGF.EvaluateExprAsBool(E->getCond()); 1450 llvm::Value *LHS = Visit(E->getLHS()); 1451 llvm::Value *RHS = Visit(E->getRHS()); 1452 return Builder.CreateSelect(CondV, LHS, RHS, "cond"); 1453 } 1454 1455 1456 llvm::BasicBlock *LHSBlock = CGF.createBasicBlock("cond.true"); 1457 llvm::BasicBlock *RHSBlock = CGF.createBasicBlock("cond.false"); 1458 llvm::BasicBlock *ContBlock = CGF.createBasicBlock("cond.end"); 1459 Value *CondVal = 0; 1460 1461 // If we don't have the GNU missing condition extension, emit a branch on 1462 // bool the normal way. 1463 if (E->getLHS()) { 1464 // Otherwise, just use EmitBranchOnBoolExpr to get small and simple code for 1465 // the branch on bool. 1466 CGF.EmitBranchOnBoolExpr(E->getCond(), LHSBlock, RHSBlock); 1467 } else { 1468 // Otherwise, for the ?: extension, evaluate the conditional and then 1469 // convert it to bool the hard way. We do this explicitly because we need 1470 // the unconverted value for the missing middle value of the ?:. 1471 CondVal = CGF.EmitScalarExpr(E->getCond()); 1472 1473 // In some cases, EmitScalarConversion will delete the "CondVal" expression 1474 // if there are no extra uses (an optimization). Inhibit this by making an 1475 // extra dead use, because we're going to add a use of CondVal later. We 1476 // don't use the builder for this, because we don't want it to get optimized 1477 // away. This leaves dead code, but the ?: extension isn't common. 1478 new llvm::BitCastInst(CondVal, CondVal->getType(), "dummy?:holder", 1479 Builder.GetInsertBlock()); 1480 1481 Value *CondBoolVal = 1482 CGF.EmitScalarConversion(CondVal, E->getCond()->getType(), 1483 CGF.getContext().BoolTy); 1484 Builder.CreateCondBr(CondBoolVal, LHSBlock, RHSBlock); 1485 } 1486 1487 CGF.PushConditionalTempDestruction(); 1488 CGF.EmitBlock(LHSBlock); 1489 1490 // Handle the GNU extension for missing LHS. 1491 Value *LHS; 1492 if (E->getLHS()) 1493 LHS = Visit(E->getLHS()); 1494 else // Perform promotions, to handle cases like "short ?: int" 1495 LHS = EmitScalarConversion(CondVal, E->getCond()->getType(), E->getType()); 1496 1497 CGF.PopConditionalTempDestruction(); 1498 LHSBlock = Builder.GetInsertBlock(); 1499 CGF.EmitBranch(ContBlock); 1500 1501 CGF.PushConditionalTempDestruction(); 1502 CGF.EmitBlock(RHSBlock); 1503 1504 Value *RHS = Visit(E->getRHS()); 1505 CGF.PopConditionalTempDestruction(); 1506 RHSBlock = Builder.GetInsertBlock(); 1507 CGF.EmitBranch(ContBlock); 1508 1509 CGF.EmitBlock(ContBlock); 1510 1511 if (!LHS || !RHS) { 1512 assert(E->getType()->isVoidType() && "Non-void value should have a value"); 1513 return 0; 1514 } 1515 1516 // Create a PHI node for the real part. 1517 llvm::PHINode *PN = Builder.CreatePHI(LHS->getType(), "cond"); 1518 PN->reserveOperandSpace(2); 1519 PN->addIncoming(LHS, LHSBlock); 1520 PN->addIncoming(RHS, RHSBlock); 1521 return PN; 1522} 1523 1524Value *ScalarExprEmitter::VisitChooseExpr(ChooseExpr *E) { 1525 return Visit(E->getChosenSubExpr(CGF.getContext())); 1526} 1527 1528Value *ScalarExprEmitter::VisitVAArgExpr(VAArgExpr *VE) { 1529 llvm::Value *ArgValue = CGF.EmitVAListRef(VE->getSubExpr()); 1530 llvm::Value *ArgPtr = CGF.EmitVAArg(ArgValue, VE->getType()); 1531 1532 // If EmitVAArg fails, we fall back to the LLVM instruction. 1533 if (!ArgPtr) 1534 return Builder.CreateVAArg(ArgValue, ConvertType(VE->getType())); 1535 1536 // FIXME Volatility. 1537 return Builder.CreateLoad(ArgPtr); 1538} 1539 1540Value *ScalarExprEmitter::VisitBlockExpr(const BlockExpr *BE) { 1541 return CGF.BuildBlockLiteralTmp(BE); 1542} 1543 1544//===----------------------------------------------------------------------===// 1545// Entry Point into this File 1546//===----------------------------------------------------------------------===// 1547 1548/// EmitScalarExpr - Emit the computation of the specified expression of 1549/// scalar type, ignoring the result. 1550Value *CodeGenFunction::EmitScalarExpr(const Expr *E, bool IgnoreResultAssign) { 1551 assert(E && !hasAggregateLLVMType(E->getType()) && 1552 "Invalid scalar expression to emit"); 1553 1554 return ScalarExprEmitter(*this, IgnoreResultAssign) 1555 .Visit(const_cast<Expr*>(E)); 1556} 1557 1558/// EmitScalarConversion - Emit a conversion from the specified type to the 1559/// specified destination type, both of which are LLVM scalar types. 1560Value *CodeGenFunction::EmitScalarConversion(Value *Src, QualType SrcTy, 1561 QualType DstTy) { 1562 assert(!hasAggregateLLVMType(SrcTy) && !hasAggregateLLVMType(DstTy) && 1563 "Invalid scalar expression to emit"); 1564 return ScalarExprEmitter(*this).EmitScalarConversion(Src, SrcTy, DstTy); 1565} 1566 1567/// EmitComplexToScalarConversion - Emit a conversion from the specified 1568/// complex type to the specified destination type, where the destination 1569/// type is an LLVM scalar type. 1570Value *CodeGenFunction::EmitComplexToScalarConversion(ComplexPairTy Src, 1571 QualType SrcTy, 1572 QualType DstTy) { 1573 assert(SrcTy->isAnyComplexType() && !hasAggregateLLVMType(DstTy) && 1574 "Invalid complex -> scalar conversion"); 1575 return ScalarExprEmitter(*this).EmitComplexToScalarConversion(Src, SrcTy, 1576 DstTy); 1577} 1578 1579Value *CodeGenFunction::EmitShuffleVector(Value* V1, Value *V2, ...) { 1580 assert(V1->getType() == V2->getType() && 1581 "Vector operands must be of the same type"); 1582 unsigned NumElements = 1583 cast<llvm::VectorType>(V1->getType())->getNumElements(); 1584 1585 va_list va; 1586 va_start(va, V2); 1587 1588 llvm::SmallVector<llvm::Constant*, 16> Args; 1589 for (unsigned i = 0; i < NumElements; i++) { 1590 int n = va_arg(va, int); 1591 assert(n >= 0 && n < (int)NumElements * 2 && 1592 "Vector shuffle index out of bounds!"); 1593 Args.push_back(VMContext.getConstantInt(llvm::Type::Int32Ty, n)); 1594 } 1595 1596 const char *Name = va_arg(va, const char *); 1597 va_end(va); 1598 1599 llvm::Constant *Mask = VMContext.getConstantVector(&Args[0], NumElements); 1600 1601 return Builder.CreateShuffleVector(V1, V2, Mask, Name); 1602} 1603 1604llvm::Value *CodeGenFunction::EmitVector(llvm::Value * const *Vals, 1605 unsigned NumVals, bool isSplat) { 1606 llvm::Value *Vec 1607 = VMContext.getUndef(VMContext.getVectorType(Vals[0]->getType(), NumVals)); 1608 1609 for (unsigned i = 0, e = NumVals; i != e; ++i) { 1610 llvm::Value *Val = isSplat ? Vals[0] : Vals[i]; 1611 llvm::Value *Idx = VMContext.getConstantInt(llvm::Type::Int32Ty, i); 1612 Vec = Builder.CreateInsertElement(Vec, Val, Idx, "tmp"); 1613 } 1614 1615 return Vec; 1616} 1617