CGExprScalar.cpp revision fb6fa30a9b06670deb14f862dddbc49a12552939
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 53public: 54 55 ScalarExprEmitter(CodeGenFunction &cgf, bool ira=false) 56 : CGF(cgf), Builder(CGF.Builder), IgnoreResultAssign(ira) { 57 } 58 59 //===--------------------------------------------------------------------===// 60 // Utilities 61 //===--------------------------------------------------------------------===// 62 63 bool TestAndClearIgnoreResultAssign() { 64 bool I = IgnoreResultAssign; IgnoreResultAssign = false; 65 return I; } 66 67 const llvm::Type *ConvertType(QualType T) { return CGF.ConvertType(T); } 68 LValue EmitLValue(const Expr *E) { return CGF.EmitLValue(E); } 69 70 Value *EmitLoadOfLValue(LValue LV, QualType T) { 71 return CGF.EmitLoadOfLValue(LV, T).getScalarVal(); 72 } 73 74 /// EmitLoadOfLValue - Given an expression with complex type that represents a 75 /// value l-value, this method emits the address of the l-value, then loads 76 /// and returns the result. 77 Value *EmitLoadOfLValue(const Expr *E) { 78 return EmitLoadOfLValue(EmitLValue(E), E->getType()); 79 } 80 81 /// EmitConversionToBool - Convert the specified expression value to a 82 /// boolean (i1) truth value. This is equivalent to "Val != 0". 83 Value *EmitConversionToBool(Value *Src, QualType DstTy); 84 85 /// EmitScalarConversion - Emit a conversion from the specified type to the 86 /// specified destination type, both of which are LLVM scalar types. 87 Value *EmitScalarConversion(Value *Src, QualType SrcTy, QualType DstTy); 88 89 /// EmitComplexToScalarConversion - Emit a conversion from the specified 90 /// complex type to the specified destination type, where the destination 91 /// type is an LLVM scalar type. 92 Value *EmitComplexToScalarConversion(CodeGenFunction::ComplexPairTy Src, 93 QualType SrcTy, QualType DstTy); 94 95 //===--------------------------------------------------------------------===// 96 // Visitor Methods 97 //===--------------------------------------------------------------------===// 98 99 Value *VisitStmt(Stmt *S) { 100 S->dump(CGF.getContext().getSourceManager()); 101 assert(0 && "Stmt can't have complex result type!"); 102 return 0; 103 } 104 Value *VisitExpr(Expr *S); 105 Value *VisitParenExpr(ParenExpr *PE) { return Visit(PE->getSubExpr()); } 106 107 // Leaves. 108 Value *VisitIntegerLiteral(const IntegerLiteral *E) { 109 return llvm::ConstantInt::get(E->getValue()); 110 } 111 Value *VisitFloatingLiteral(const FloatingLiteral *E) { 112 return llvm::ConstantFP::get(E->getValue()); 113 } 114 Value *VisitCharacterLiteral(const CharacterLiteral *E) { 115 return llvm::ConstantInt::get(ConvertType(E->getType()), E->getValue()); 116 } 117 Value *VisitCXXBoolLiteralExpr(const CXXBoolLiteralExpr *E) { 118 return llvm::ConstantInt::get(ConvertType(E->getType()), E->getValue()); 119 } 120 Value *VisitCXXZeroInitValueExpr(const CXXZeroInitValueExpr *E) { 121 return llvm::Constant::getNullValue(ConvertType(E->getType())); 122 } 123 Value *VisitGNUNullExpr(const GNUNullExpr *E) { 124 return llvm::Constant::getNullValue(ConvertType(E->getType())); 125 } 126 Value *VisitTypesCompatibleExpr(const TypesCompatibleExpr *E) { 127 return llvm::ConstantInt::get(ConvertType(E->getType()), 128 CGF.getContext().typesAreCompatible( 129 E->getArgType1(), E->getArgType2())); 130 } 131 Value *VisitSizeOfAlignOfExpr(const SizeOfAlignOfExpr *E); 132 Value *VisitAddrLabelExpr(const AddrLabelExpr *E) { 133 llvm::Value *V = 134 llvm::ConstantInt::get(llvm::Type::Int32Ty, 135 CGF.GetIDForAddrOfLabel(E->getLabel())); 136 137 return Builder.CreateIntToPtr(V, ConvertType(E->getType())); 138 } 139 140 // l-values. 141 Value *VisitDeclRefExpr(DeclRefExpr *E) { 142 if (const EnumConstantDecl *EC = dyn_cast<EnumConstantDecl>(E->getDecl())) 143 return llvm::ConstantInt::get(EC->getInitVal()); 144 return EmitLoadOfLValue(E); 145 } 146 Value *VisitObjCSelectorExpr(ObjCSelectorExpr *E) { 147 return CGF.EmitObjCSelectorExpr(E); 148 } 149 Value *VisitObjCProtocolExpr(ObjCProtocolExpr *E) { 150 return CGF.EmitObjCProtocolExpr(E); 151 } 152 Value *VisitObjCIvarRefExpr(ObjCIvarRefExpr *E) { 153 return EmitLoadOfLValue(E); 154 } 155 Value *VisitObjCPropertyRefExpr(ObjCPropertyRefExpr *E) { 156 return EmitLoadOfLValue(E); 157 } 158 Value *VisitObjCKVCRefExpr(ObjCKVCRefExpr *E) { 159 return EmitLoadOfLValue(E); 160 } 161 Value *VisitObjCMessageExpr(ObjCMessageExpr *E) { 162 return CGF.EmitObjCMessageExpr(E).getScalarVal(); 163 } 164 165 Value *VisitArraySubscriptExpr(ArraySubscriptExpr *E); 166 Value *VisitShuffleVectorExpr(ShuffleVectorExpr *E); 167 Value *VisitMemberExpr(Expr *E) { return EmitLoadOfLValue(E); } 168 Value *VisitExtVectorElementExpr(Expr *E) { return EmitLoadOfLValue(E); } 169 Value *VisitCompoundLiteralExpr(CompoundLiteralExpr *E) { 170 return EmitLoadOfLValue(E); 171 } 172 Value *VisitStringLiteral(Expr *E) { return EmitLValue(E).getAddress(); } 173 Value *VisitObjCEncodeExpr(const ObjCEncodeExpr *E) { 174 return EmitLValue(E).getAddress(); 175 } 176 177 Value *VisitPredefinedExpr(Expr *E) { return EmitLValue(E).getAddress(); } 178 179 Value *VisitInitListExpr(InitListExpr *E) { 180 bool Ignore = TestAndClearIgnoreResultAssign(); 181 (void)Ignore; 182 assert (Ignore == false && "init list ignored"); 183 unsigned NumInitElements = E->getNumInits(); 184 185 if (E->hadArrayRangeDesignator()) { 186 CGF.ErrorUnsupported(E, "GNU array range designator extension"); 187 } 188 189 const llvm::VectorType *VType = 190 dyn_cast<llvm::VectorType>(ConvertType(E->getType())); 191 192 // We have a scalar in braces. Just use the first element. 193 if (!VType) 194 return Visit(E->getInit(0)); 195 196 unsigned NumVectorElements = VType->getNumElements(); 197 const llvm::Type *ElementType = VType->getElementType(); 198 199 // Emit individual vector element stores. 200 llvm::Value *V = llvm::UndefValue::get(VType); 201 202 // Emit initializers 203 unsigned i; 204 for (i = 0; i < NumInitElements; ++i) { 205 Value *NewV = Visit(E->getInit(i)); 206 Value *Idx = llvm::ConstantInt::get(llvm::Type::Int32Ty, i); 207 V = Builder.CreateInsertElement(V, NewV, Idx); 208 } 209 210 // Emit remaining default initializers 211 for (/* Do not initialize i*/; i < NumVectorElements; ++i) { 212 Value *Idx = llvm::ConstantInt::get(llvm::Type::Int32Ty, i); 213 llvm::Value *NewV = llvm::Constant::getNullValue(ElementType); 214 V = Builder.CreateInsertElement(V, NewV, Idx); 215 } 216 217 return V; 218 } 219 220 Value *VisitImplicitValueInitExpr(const ImplicitValueInitExpr *E) { 221 return llvm::Constant::getNullValue(ConvertType(E->getType())); 222 } 223 Value *VisitImplicitCastExpr(const ImplicitCastExpr *E); 224 Value *VisitCastExpr(const CastExpr *E) { 225 // Make sure to evaluate VLA bounds now so that we have them for later. 226 if (E->getType()->isVariablyModifiedType()) 227 CGF.EmitVLASize(E->getType()); 228 229 return EmitCastExpr(E->getSubExpr(), E->getType()); 230 } 231 Value *EmitCastExpr(const Expr *E, QualType T); 232 233 Value *VisitCallExpr(const CallExpr *E) { 234 if (E->getCallReturnType()->isReferenceType()) 235 return EmitLoadOfLValue(E); 236 237 return CGF.EmitCallExpr(E).getScalarVal(); 238 } 239 240 Value *VisitStmtExpr(const StmtExpr *E); 241 242 Value *VisitBlockDeclRefExpr(const BlockDeclRefExpr *E); 243 244 // Unary Operators. 245 Value *VisitPrePostIncDec(const UnaryOperator *E, bool isInc, bool isPre); 246 Value *VisitUnaryPostDec(const UnaryOperator *E) { 247 return VisitPrePostIncDec(E, false, false); 248 } 249 Value *VisitUnaryPostInc(const UnaryOperator *E) { 250 return VisitPrePostIncDec(E, true, false); 251 } 252 Value *VisitUnaryPreDec(const UnaryOperator *E) { 253 return VisitPrePostIncDec(E, false, true); 254 } 255 Value *VisitUnaryPreInc(const UnaryOperator *E) { 256 return VisitPrePostIncDec(E, true, true); 257 } 258 Value *VisitUnaryAddrOf(const UnaryOperator *E) { 259 return EmitLValue(E->getSubExpr()).getAddress(); 260 } 261 Value *VisitUnaryDeref(const Expr *E) { return EmitLoadOfLValue(E); } 262 Value *VisitUnaryPlus(const UnaryOperator *E) { 263 // This differs from gcc, though, most likely due to a bug in gcc. 264 TestAndClearIgnoreResultAssign(); 265 return Visit(E->getSubExpr()); 266 } 267 Value *VisitUnaryMinus (const UnaryOperator *E); 268 Value *VisitUnaryNot (const UnaryOperator *E); 269 Value *VisitUnaryLNot (const UnaryOperator *E); 270 Value *VisitUnaryReal (const UnaryOperator *E); 271 Value *VisitUnaryImag (const UnaryOperator *E); 272 Value *VisitUnaryExtension(const UnaryOperator *E) { 273 return Visit(E->getSubExpr()); 274 } 275 Value *VisitUnaryOffsetOf(const UnaryOperator *E); 276 277 // C++ 278 Value *VisitCXXDefaultArgExpr(CXXDefaultArgExpr *DAE) { 279 return Visit(DAE->getExpr()); 280 } 281 Value *VisitCXXThisExpr(CXXThisExpr *TE) { 282 return CGF.LoadCXXThis(); 283 } 284 285 Value *VisitCXXExprWithTemporaries(CXXExprWithTemporaries *E) { 286 return CGF.EmitCXXExprWithTemporaries(E).getScalarVal(); 287 } 288 Value *VisitCXXNewExpr(const CXXNewExpr *E) { 289 return CGF.EmitCXXNewExpr(E); 290 } 291 292 // Binary Operators. 293 Value *EmitMul(const BinOpInfo &Ops) { 294 if (CGF.getContext().getLangOptions().OverflowChecking 295 && Ops.Ty->isSignedIntegerType()) 296 return EmitOverflowCheckedBinOp(Ops); 297 return Builder.CreateMul(Ops.LHS, Ops.RHS, "mul"); 298 } 299 /// Create a binary op that checks for overflow. 300 /// Currently only supports +, - and *. 301 Value *EmitOverflowCheckedBinOp(const BinOpInfo &Ops); 302 Value *EmitDiv(const BinOpInfo &Ops); 303 Value *EmitRem(const BinOpInfo &Ops); 304 Value *EmitAdd(const BinOpInfo &Ops); 305 Value *EmitSub(const BinOpInfo &Ops); 306 Value *EmitShl(const BinOpInfo &Ops); 307 Value *EmitShr(const BinOpInfo &Ops); 308 Value *EmitAnd(const BinOpInfo &Ops) { 309 return Builder.CreateAnd(Ops.LHS, Ops.RHS, "and"); 310 } 311 Value *EmitXor(const BinOpInfo &Ops) { 312 return Builder.CreateXor(Ops.LHS, Ops.RHS, "xor"); 313 } 314 Value *EmitOr (const BinOpInfo &Ops) { 315 return Builder.CreateOr(Ops.LHS, Ops.RHS, "or"); 316 } 317 318 BinOpInfo EmitBinOps(const BinaryOperator *E); 319 Value *EmitCompoundAssign(const CompoundAssignOperator *E, 320 Value *(ScalarExprEmitter::*F)(const BinOpInfo &)); 321 322 // Binary operators and binary compound assignment operators. 323#define HANDLEBINOP(OP) \ 324 Value *VisitBin ## OP(const BinaryOperator *E) { \ 325 return Emit ## OP(EmitBinOps(E)); \ 326 } \ 327 Value *VisitBin ## OP ## Assign(const CompoundAssignOperator *E) { \ 328 return EmitCompoundAssign(E, &ScalarExprEmitter::Emit ## OP); \ 329 } 330 HANDLEBINOP(Mul); 331 HANDLEBINOP(Div); 332 HANDLEBINOP(Rem); 333 HANDLEBINOP(Add); 334 HANDLEBINOP(Sub); 335 HANDLEBINOP(Shl); 336 HANDLEBINOP(Shr); 337 HANDLEBINOP(And); 338 HANDLEBINOP(Xor); 339 HANDLEBINOP(Or); 340#undef HANDLEBINOP 341 342 // Comparisons. 343 Value *EmitCompare(const BinaryOperator *E, unsigned UICmpOpc, 344 unsigned SICmpOpc, unsigned FCmpOpc); 345#define VISITCOMP(CODE, UI, SI, FP) \ 346 Value *VisitBin##CODE(const BinaryOperator *E) { \ 347 return EmitCompare(E, llvm::ICmpInst::UI, llvm::ICmpInst::SI, \ 348 llvm::FCmpInst::FP); } 349 VISITCOMP(LT, ICMP_ULT, ICMP_SLT, FCMP_OLT); 350 VISITCOMP(GT, ICMP_UGT, ICMP_SGT, FCMP_OGT); 351 VISITCOMP(LE, ICMP_ULE, ICMP_SLE, FCMP_OLE); 352 VISITCOMP(GE, ICMP_UGE, ICMP_SGE, FCMP_OGE); 353 VISITCOMP(EQ, ICMP_EQ , ICMP_EQ , FCMP_OEQ); 354 VISITCOMP(NE, ICMP_NE , ICMP_NE , FCMP_UNE); 355#undef VISITCOMP 356 357 Value *VisitBinAssign (const BinaryOperator *E); 358 359 Value *VisitBinLAnd (const BinaryOperator *E); 360 Value *VisitBinLOr (const BinaryOperator *E); 361 Value *VisitBinComma (const BinaryOperator *E); 362 363 // Other Operators. 364 Value *VisitBlockExpr(const BlockExpr *BE); 365 Value *VisitConditionalOperator(const ConditionalOperator *CO); 366 Value *VisitChooseExpr(ChooseExpr *CE); 367 Value *VisitVAArgExpr(VAArgExpr *VE); 368 Value *VisitObjCStringLiteral(const ObjCStringLiteral *E) { 369 return CGF.EmitObjCStringLiteral(E); 370 } 371}; 372} // end anonymous namespace. 373 374//===----------------------------------------------------------------------===// 375// Utilities 376//===----------------------------------------------------------------------===// 377 378/// EmitConversionToBool - Convert the specified expression value to a 379/// boolean (i1) truth value. This is equivalent to "Val != 0". 380Value *ScalarExprEmitter::EmitConversionToBool(Value *Src, QualType SrcType) { 381 assert(SrcType->isCanonical() && "EmitScalarConversion strips typedefs"); 382 383 if (SrcType->isRealFloatingType()) { 384 // Compare against 0.0 for fp scalars. 385 llvm::Value *Zero = llvm::Constant::getNullValue(Src->getType()); 386 return Builder.CreateFCmpUNE(Src, Zero, "tobool"); 387 } 388 389 assert((SrcType->isIntegerType() || isa<llvm::PointerType>(Src->getType())) && 390 "Unknown scalar type to convert"); 391 392 // Because of the type rules of C, we often end up computing a logical value, 393 // then zero extending it to int, then wanting it as a logical value again. 394 // Optimize this common case. 395 if (llvm::ZExtInst *ZI = dyn_cast<llvm::ZExtInst>(Src)) { 396 if (ZI->getOperand(0)->getType() == llvm::Type::Int1Ty) { 397 Value *Result = ZI->getOperand(0); 398 // If there aren't any more uses, zap the instruction to save space. 399 // Note that there can be more uses, for example if this 400 // is the result of an assignment. 401 if (ZI->use_empty()) 402 ZI->eraseFromParent(); 403 return Result; 404 } 405 } 406 407 // Compare against an integer or pointer null. 408 llvm::Value *Zero = llvm::Constant::getNullValue(Src->getType()); 409 return Builder.CreateICmpNE(Src, Zero, "tobool"); 410} 411 412/// EmitScalarConversion - Emit a conversion from the specified type to the 413/// specified destination type, both of which are LLVM scalar types. 414Value *ScalarExprEmitter::EmitScalarConversion(Value *Src, QualType SrcType, 415 QualType DstType) { 416 SrcType = CGF.getContext().getCanonicalType(SrcType); 417 DstType = CGF.getContext().getCanonicalType(DstType); 418 if (SrcType == DstType) return Src; 419 420 if (DstType->isVoidType()) return 0; 421 422 // Handle conversions to bool first, they are special: comparisons against 0. 423 if (DstType->isBooleanType()) 424 return EmitConversionToBool(Src, SrcType); 425 426 const llvm::Type *DstTy = ConvertType(DstType); 427 428 // Ignore conversions like int -> uint. 429 if (Src->getType() == DstTy) 430 return Src; 431 432 // Handle pointer conversions next: pointers can only be converted 433 // to/from other pointers and integers. Check for pointer types in 434 // terms of LLVM, as some native types (like Obj-C id) may map to a 435 // pointer type. 436 if (isa<llvm::PointerType>(DstTy)) { 437 // The source value may be an integer, or a pointer. 438 if (isa<llvm::PointerType>(Src->getType())) 439 return Builder.CreateBitCast(Src, DstTy, "conv"); 440 assert(SrcType->isIntegerType() && "Not ptr->ptr or int->ptr conversion?"); 441 // First, convert to the correct width so that we control the kind of 442 // extension. 443 const llvm::Type *MiddleTy = llvm::IntegerType::get(CGF.LLVMPointerWidth); 444 bool InputSigned = SrcType->isSignedIntegerType(); 445 llvm::Value* IntResult = 446 Builder.CreateIntCast(Src, MiddleTy, InputSigned, "conv"); 447 // Then, cast to pointer. 448 return Builder.CreateIntToPtr(IntResult, DstTy, "conv"); 449 } 450 451 if (isa<llvm::PointerType>(Src->getType())) { 452 // Must be an ptr to int cast. 453 assert(isa<llvm::IntegerType>(DstTy) && "not ptr->int?"); 454 return Builder.CreatePtrToInt(Src, DstTy, "conv"); 455 } 456 457 // A scalar can be splatted to an extended vector of the same element type 458 if (DstType->isExtVectorType() && !isa<VectorType>(SrcType)) { 459 // Cast the scalar to element type 460 QualType EltTy = DstType->getAsExtVectorType()->getElementType(); 461 llvm::Value *Elt = EmitScalarConversion(Src, SrcType, EltTy); 462 463 // Insert the element in element zero of an undef vector 464 llvm::Value *UnV = llvm::UndefValue::get(DstTy); 465 llvm::Value *Idx = llvm::ConstantInt::get(llvm::Type::Int32Ty, 0); 466 UnV = Builder.CreateInsertElement(UnV, Elt, Idx, "tmp"); 467 468 // Splat the element across to all elements 469 llvm::SmallVector<llvm::Constant*, 16> Args; 470 unsigned NumElements = cast<llvm::VectorType>(DstTy)->getNumElements(); 471 for (unsigned i = 0; i < NumElements; i++) 472 Args.push_back(llvm::ConstantInt::get(llvm::Type::Int32Ty, 0)); 473 474 llvm::Constant *Mask = llvm::ConstantVector::get(&Args[0], NumElements); 475 llvm::Value *Yay = Builder.CreateShuffleVector(UnV, UnV, Mask, "splat"); 476 return Yay; 477 } 478 479 // Allow bitcast from vector to integer/fp of the same size. 480 if (isa<llvm::VectorType>(Src->getType()) || 481 isa<llvm::VectorType>(DstTy)) 482 return Builder.CreateBitCast(Src, DstTy, "conv"); 483 484 // Finally, we have the arithmetic types: real int/float. 485 if (isa<llvm::IntegerType>(Src->getType())) { 486 bool InputSigned = SrcType->isSignedIntegerType(); 487 if (isa<llvm::IntegerType>(DstTy)) 488 return Builder.CreateIntCast(Src, DstTy, InputSigned, "conv"); 489 else if (InputSigned) 490 return Builder.CreateSIToFP(Src, DstTy, "conv"); 491 else 492 return Builder.CreateUIToFP(Src, DstTy, "conv"); 493 } 494 495 assert(Src->getType()->isFloatingPoint() && "Unknown real conversion"); 496 if (isa<llvm::IntegerType>(DstTy)) { 497 if (DstType->isSignedIntegerType()) 498 return Builder.CreateFPToSI(Src, DstTy, "conv"); 499 else 500 return Builder.CreateFPToUI(Src, DstTy, "conv"); 501 } 502 503 assert(DstTy->isFloatingPoint() && "Unknown real conversion"); 504 if (DstTy->getTypeID() < Src->getType()->getTypeID()) 505 return Builder.CreateFPTrunc(Src, DstTy, "conv"); 506 else 507 return Builder.CreateFPExt(Src, DstTy, "conv"); 508} 509 510/// EmitComplexToScalarConversion - Emit a conversion from the specified 511/// complex type to the specified destination type, where the destination 512/// type is an LLVM scalar type. 513Value *ScalarExprEmitter:: 514EmitComplexToScalarConversion(CodeGenFunction::ComplexPairTy Src, 515 QualType SrcTy, QualType DstTy) { 516 // Get the source element type. 517 SrcTy = SrcTy->getAsComplexType()->getElementType(); 518 519 // Handle conversions to bool first, they are special: comparisons against 0. 520 if (DstTy->isBooleanType()) { 521 // Complex != 0 -> (Real != 0) | (Imag != 0) 522 Src.first = EmitScalarConversion(Src.first, SrcTy, DstTy); 523 Src.second = EmitScalarConversion(Src.second, SrcTy, DstTy); 524 return Builder.CreateOr(Src.first, Src.second, "tobool"); 525 } 526 527 // C99 6.3.1.7p2: "When a value of complex type is converted to a real type, 528 // the imaginary part of the complex value is discarded and the value of the 529 // real part is converted according to the conversion rules for the 530 // corresponding real type. 531 return EmitScalarConversion(Src.first, SrcTy, DstTy); 532} 533 534 535//===----------------------------------------------------------------------===// 536// Visitor Methods 537//===----------------------------------------------------------------------===// 538 539Value *ScalarExprEmitter::VisitExpr(Expr *E) { 540 CGF.ErrorUnsupported(E, "scalar expression"); 541 if (E->getType()->isVoidType()) 542 return 0; 543 return llvm::UndefValue::get(CGF.ConvertType(E->getType())); 544} 545 546Value *ScalarExprEmitter::VisitShuffleVectorExpr(ShuffleVectorExpr *E) { 547 llvm::SmallVector<llvm::Constant*, 32> indices; 548 for (unsigned i = 2; i < E->getNumSubExprs(); i++) { 549 indices.push_back(cast<llvm::Constant>(CGF.EmitScalarExpr(E->getExpr(i)))); 550 } 551 Value* V1 = CGF.EmitScalarExpr(E->getExpr(0)); 552 Value* V2 = CGF.EmitScalarExpr(E->getExpr(1)); 553 Value* SV = llvm::ConstantVector::get(indices.begin(), indices.size()); 554 return Builder.CreateShuffleVector(V1, V2, SV, "shuffle"); 555} 556 557Value *ScalarExprEmitter::VisitArraySubscriptExpr(ArraySubscriptExpr *E) { 558 TestAndClearIgnoreResultAssign(); 559 560 // Emit subscript expressions in rvalue context's. For most cases, this just 561 // loads the lvalue formed by the subscript expr. However, we have to be 562 // careful, because the base of a vector subscript is occasionally an rvalue, 563 // so we can't get it as an lvalue. 564 if (!E->getBase()->getType()->isVectorType()) 565 return EmitLoadOfLValue(E); 566 567 // Handle the vector case. The base must be a vector, the index must be an 568 // integer value. 569 Value *Base = Visit(E->getBase()); 570 Value *Idx = Visit(E->getIdx()); 571 bool IdxSigned = E->getIdx()->getType()->isSignedIntegerType(); 572 Idx = Builder.CreateIntCast(Idx, llvm::Type::Int32Ty, IdxSigned, 573 "vecidxcast"); 574 return Builder.CreateExtractElement(Base, Idx, "vecext"); 575} 576 577/// VisitImplicitCastExpr - Implicit casts are the same as normal casts, but 578/// also handle things like function to pointer-to-function decay, and array to 579/// pointer decay. 580Value *ScalarExprEmitter::VisitImplicitCastExpr(const ImplicitCastExpr *E) { 581 const Expr *Op = E->getSubExpr(); 582 583 // If this is due to array->pointer conversion, emit the array expression as 584 // an l-value. 585 if (Op->getType()->isArrayType()) { 586 Value *V = EmitLValue(Op).getAddress(); // Bitfields can't be arrays. 587 588 // Note that VLA pointers are always decayed, so we don't need to do 589 // anything here. 590 if (!Op->getType()->isVariableArrayType()) { 591 assert(isa<llvm::PointerType>(V->getType()) && "Expected pointer"); 592 assert(isa<llvm::ArrayType>(cast<llvm::PointerType>(V->getType()) 593 ->getElementType()) && 594 "Expected pointer to array"); 595 V = Builder.CreateStructGEP(V, 0, "arraydecay"); 596 } 597 598 // The resultant pointer type can be implicitly casted to other pointer 599 // types as well (e.g. void*) and can be implicitly converted to integer. 600 const llvm::Type *DestTy = ConvertType(E->getType()); 601 if (V->getType() != DestTy) { 602 if (isa<llvm::PointerType>(DestTy)) 603 V = Builder.CreateBitCast(V, DestTy, "ptrconv"); 604 else { 605 assert(isa<llvm::IntegerType>(DestTy) && "Unknown array decay"); 606 V = Builder.CreatePtrToInt(V, DestTy, "ptrconv"); 607 } 608 } 609 return V; 610 } 611 612 return EmitCastExpr(Op, E->getType()); 613} 614 615 616// VisitCastExpr - Emit code for an explicit or implicit cast. Implicit casts 617// have to handle a more broad range of conversions than explicit casts, as they 618// handle things like function to ptr-to-function decay etc. 619Value *ScalarExprEmitter::EmitCastExpr(const Expr *E, QualType DestTy) { 620 if (!DestTy->isVoidType()) 621 TestAndClearIgnoreResultAssign(); 622 623 // Handle cases where the source is an non-complex type. 624 625 if (!CGF.hasAggregateLLVMType(E->getType())) { 626 Value *Src = Visit(const_cast<Expr*>(E)); 627 628 // Use EmitScalarConversion to perform the conversion. 629 return EmitScalarConversion(Src, E->getType(), DestTy); 630 } 631 632 if (E->getType()->isAnyComplexType()) { 633 // Handle cases where the source is a complex type. 634 bool IgnoreImag = true; 635 bool IgnoreImagAssign = true; 636 bool IgnoreReal = IgnoreResultAssign; 637 bool IgnoreRealAssign = IgnoreResultAssign; 638 if (DestTy->isBooleanType()) 639 IgnoreImagAssign = IgnoreImag = false; 640 else if (DestTy->isVoidType()) { 641 IgnoreReal = IgnoreImag = false; 642 IgnoreRealAssign = IgnoreImagAssign = true; 643 } 644 CodeGenFunction::ComplexPairTy V 645 = CGF.EmitComplexExpr(E, IgnoreReal, IgnoreImag, IgnoreRealAssign, 646 IgnoreImagAssign); 647 return EmitComplexToScalarConversion(V, E->getType(), DestTy); 648 } 649 650 // Okay, this is a cast from an aggregate. It must be a cast to void. Just 651 // evaluate the result and return. 652 CGF.EmitAggExpr(E, 0, false, true); 653 return 0; 654} 655 656Value *ScalarExprEmitter::VisitStmtExpr(const StmtExpr *E) { 657 return CGF.EmitCompoundStmt(*E->getSubStmt(), 658 !E->getType()->isVoidType()).getScalarVal(); 659} 660 661Value *ScalarExprEmitter::VisitBlockDeclRefExpr(const BlockDeclRefExpr *E) { 662 return Builder.CreateLoad(CGF.GetAddrOfBlockDecl(E), false, "tmp"); 663} 664 665//===----------------------------------------------------------------------===// 666// Unary Operators 667//===----------------------------------------------------------------------===// 668 669Value *ScalarExprEmitter::VisitPrePostIncDec(const UnaryOperator *E, 670 bool isInc, bool isPre) { 671 LValue LV = EmitLValue(E->getSubExpr()); 672 QualType ValTy = E->getSubExpr()->getType(); 673 Value *InVal = CGF.EmitLoadOfLValue(LV, ValTy).getScalarVal(); 674 675 int AmountVal = isInc ? 1 : -1; 676 677 if (ValTy->isPointerType() && 678 ValTy->getAsPointerType()->isVariableArrayType()) { 679 // The amount of the addition/subtraction needs to account for the VLA size 680 CGF.ErrorUnsupported(E, "VLA pointer inc/dec"); 681 } 682 683 Value *NextVal; 684 if (const llvm::PointerType *PT = 685 dyn_cast<llvm::PointerType>(InVal->getType())) { 686 llvm::Constant *Inc =llvm::ConstantInt::get(llvm::Type::Int32Ty, AmountVal); 687 if (!isa<llvm::FunctionType>(PT->getElementType())) { 688 NextVal = Builder.CreateGEP(InVal, Inc, "ptrincdec"); 689 } else { 690 const llvm::Type *i8Ty = llvm::PointerType::getUnqual(llvm::Type::Int8Ty); 691 NextVal = Builder.CreateBitCast(InVal, i8Ty, "tmp"); 692 NextVal = Builder.CreateGEP(NextVal, Inc, "ptrincdec"); 693 NextVal = Builder.CreateBitCast(NextVal, InVal->getType()); 694 } 695 } else if (InVal->getType() == llvm::Type::Int1Ty && isInc) { 696 // Bool++ is an interesting case, due to promotion rules, we get: 697 // Bool++ -> Bool = Bool+1 -> Bool = (int)Bool+1 -> 698 // Bool = ((int)Bool+1) != 0 699 // An interesting aspect of this is that increment is always true. 700 // Decrement does not have this property. 701 NextVal = llvm::ConstantInt::getTrue(); 702 } else { 703 // Add the inc/dec to the real part. 704 if (isa<llvm::IntegerType>(InVal->getType())) 705 NextVal = llvm::ConstantInt::get(InVal->getType(), AmountVal); 706 else if (InVal->getType() == llvm::Type::FloatTy) 707 NextVal = 708 llvm::ConstantFP::get(llvm::APFloat(static_cast<float>(AmountVal))); 709 else if (InVal->getType() == llvm::Type::DoubleTy) 710 NextVal = 711 llvm::ConstantFP::get(llvm::APFloat(static_cast<double>(AmountVal))); 712 else { 713 llvm::APFloat F(static_cast<float>(AmountVal)); 714 bool ignored; 715 F.convert(CGF.Target.getLongDoubleFormat(), llvm::APFloat::rmTowardZero, 716 &ignored); 717 NextVal = llvm::ConstantFP::get(F); 718 } 719 NextVal = Builder.CreateAdd(InVal, NextVal, isInc ? "inc" : "dec"); 720 } 721 722 // Store the updated result through the lvalue. 723 if (LV.isBitfield()) 724 CGF.EmitStoreThroughBitfieldLValue(RValue::get(NextVal), LV, ValTy, 725 &NextVal); 726 else 727 CGF.EmitStoreThroughLValue(RValue::get(NextVal), LV, ValTy); 728 729 // If this is a postinc, return the value read from memory, otherwise use the 730 // updated value. 731 return isPre ? NextVal : InVal; 732} 733 734 735Value *ScalarExprEmitter::VisitUnaryMinus(const UnaryOperator *E) { 736 TestAndClearIgnoreResultAssign(); 737 Value *Op = Visit(E->getSubExpr()); 738 return Builder.CreateNeg(Op, "neg"); 739} 740 741Value *ScalarExprEmitter::VisitUnaryNot(const UnaryOperator *E) { 742 TestAndClearIgnoreResultAssign(); 743 Value *Op = Visit(E->getSubExpr()); 744 return Builder.CreateNot(Op, "neg"); 745} 746 747Value *ScalarExprEmitter::VisitUnaryLNot(const UnaryOperator *E) { 748 // Compare operand to zero. 749 Value *BoolVal = CGF.EvaluateExprAsBool(E->getSubExpr()); 750 751 // Invert value. 752 // TODO: Could dynamically modify easy computations here. For example, if 753 // the operand is an icmp ne, turn into icmp eq. 754 BoolVal = Builder.CreateNot(BoolVal, "lnot"); 755 756 // ZExt result to the expr type. 757 return Builder.CreateZExt(BoolVal, ConvertType(E->getType()), "lnot.ext"); 758} 759 760/// VisitSizeOfAlignOfExpr - Return the size or alignment of the type of 761/// argument of the sizeof expression as an integer. 762Value * 763ScalarExprEmitter::VisitSizeOfAlignOfExpr(const SizeOfAlignOfExpr *E) { 764 QualType TypeToSize = E->getTypeOfArgument(); 765 if (E->isSizeOf()) { 766 if (const VariableArrayType *VAT = 767 CGF.getContext().getAsVariableArrayType(TypeToSize)) { 768 if (E->isArgumentType()) { 769 // sizeof(type) - make sure to emit the VLA size. 770 CGF.EmitVLASize(TypeToSize); 771 } else { 772 // C99 6.5.3.4p2: If the argument is an expression of type 773 // VLA, it is evaluated. 774 CGF.EmitAnyExpr(E->getArgumentExpr()); 775 } 776 777 return CGF.GetVLASize(VAT); 778 } 779 } 780 781 // If this isn't sizeof(vla), the result must be constant; use the 782 // constant folding logic so we don't have to duplicate it here. 783 Expr::EvalResult Result; 784 E->Evaluate(Result, CGF.getContext()); 785 return llvm::ConstantInt::get(Result.Val.getInt()); 786} 787 788Value *ScalarExprEmitter::VisitUnaryReal(const UnaryOperator *E) { 789 Expr *Op = E->getSubExpr(); 790 if (Op->getType()->isAnyComplexType()) 791 return CGF.EmitComplexExpr(Op, false, true, false, true).first; 792 return Visit(Op); 793} 794Value *ScalarExprEmitter::VisitUnaryImag(const UnaryOperator *E) { 795 Expr *Op = E->getSubExpr(); 796 if (Op->getType()->isAnyComplexType()) 797 return CGF.EmitComplexExpr(Op, true, false, true, false).second; 798 799 // __imag on a scalar returns zero. Emit the subexpr to ensure side 800 // effects are evaluated, but not the actual value. 801 if (E->isLvalue(CGF.getContext()) == Expr::LV_Valid) 802 CGF.EmitLValue(Op); 803 else 804 CGF.EmitScalarExpr(Op, true); 805 return llvm::Constant::getNullValue(ConvertType(E->getType())); 806} 807 808Value *ScalarExprEmitter::VisitUnaryOffsetOf(const UnaryOperator *E) 809{ 810 Value* ResultAsPtr = EmitLValue(E->getSubExpr()).getAddress(); 811 const llvm::Type* ResultType = ConvertType(E->getType()); 812 return Builder.CreatePtrToInt(ResultAsPtr, ResultType, "offsetof"); 813} 814 815//===----------------------------------------------------------------------===// 816// Binary Operators 817//===----------------------------------------------------------------------===// 818 819BinOpInfo ScalarExprEmitter::EmitBinOps(const BinaryOperator *E) { 820 TestAndClearIgnoreResultAssign(); 821 BinOpInfo Result; 822 Result.LHS = Visit(E->getLHS()); 823 Result.RHS = Visit(E->getRHS()); 824 Result.Ty = E->getType(); 825 Result.E = E; 826 return Result; 827} 828 829Value *ScalarExprEmitter::EmitCompoundAssign(const CompoundAssignOperator *E, 830 Value *(ScalarExprEmitter::*Func)(const BinOpInfo &)) { 831 bool Ignore = TestAndClearIgnoreResultAssign(); 832 QualType LHSTy = E->getLHS()->getType(), RHSTy = E->getRHS()->getType(); 833 834 BinOpInfo OpInfo; 835 836 if (E->getComputationResultType()->isAnyComplexType()) { 837 // This needs to go through the complex expression emitter, but 838 // it's a tad complicated to do that... I'm leaving it out for now. 839 // (Note that we do actually need the imaginary part of the RHS for 840 // multiplication and division.) 841 CGF.ErrorUnsupported(E, "complex compound assignment"); 842 return llvm::UndefValue::get(CGF.ConvertType(E->getType())); 843 } 844 845 // Emit the RHS first. __block variables need to have the rhs evaluated 846 // first, plus this should improve codegen a little. 847 OpInfo.RHS = Visit(E->getRHS()); 848 OpInfo.Ty = E->getComputationResultType(); 849 OpInfo.E = E; 850 // Load/convert the LHS. 851 LValue LHSLV = EmitLValue(E->getLHS()); 852 OpInfo.LHS = EmitLoadOfLValue(LHSLV, LHSTy); 853 OpInfo.LHS = EmitScalarConversion(OpInfo.LHS, LHSTy, 854 E->getComputationLHSType()); 855 856 // Expand the binary operator. 857 Value *Result = (this->*Func)(OpInfo); 858 859 // Convert the result back to the LHS type. 860 Result = EmitScalarConversion(Result, E->getComputationResultType(), LHSTy); 861 862 // Store the result value into the LHS lvalue. Bit-fields are 863 // handled specially because the result is altered by the store, 864 // i.e., [C99 6.5.16p1] 'An assignment expression has the value of 865 // the left operand after the assignment...'. 866 if (LHSLV.isBitfield()) { 867 if (!LHSLV.isVolatileQualified()) { 868 CGF.EmitStoreThroughBitfieldLValue(RValue::get(Result), LHSLV, LHSTy, 869 &Result); 870 return Result; 871 } else 872 CGF.EmitStoreThroughBitfieldLValue(RValue::get(Result), LHSLV, LHSTy); 873 } else 874 CGF.EmitStoreThroughLValue(RValue::get(Result), LHSLV, LHSTy); 875 if (Ignore) 876 return 0; 877 return EmitLoadOfLValue(LHSLV, E->getType()); 878} 879 880 881Value *ScalarExprEmitter::EmitDiv(const BinOpInfo &Ops) { 882 if (Ops.LHS->getType()->isFPOrFPVector()) 883 return Builder.CreateFDiv(Ops.LHS, Ops.RHS, "div"); 884 else if (Ops.Ty->isUnsignedIntegerType()) 885 return Builder.CreateUDiv(Ops.LHS, Ops.RHS, "div"); 886 else 887 return Builder.CreateSDiv(Ops.LHS, Ops.RHS, "div"); 888} 889 890Value *ScalarExprEmitter::EmitRem(const BinOpInfo &Ops) { 891 // Rem in C can't be a floating point type: C99 6.5.5p2. 892 if (Ops.Ty->isUnsignedIntegerType()) 893 return Builder.CreateURem(Ops.LHS, Ops.RHS, "rem"); 894 else 895 return Builder.CreateSRem(Ops.LHS, Ops.RHS, "rem"); 896} 897 898Value *ScalarExprEmitter::EmitOverflowCheckedBinOp(const BinOpInfo &Ops) { 899 unsigned IID; 900 unsigned OpID = 0; 901 902 switch (Ops.E->getOpcode()) { 903 case BinaryOperator::Add: 904 case BinaryOperator::AddAssign: 905 OpID = 1; 906 IID = llvm::Intrinsic::sadd_with_overflow; 907 break; 908 case BinaryOperator::Sub: 909 case BinaryOperator::SubAssign: 910 OpID = 2; 911 IID = llvm::Intrinsic::ssub_with_overflow; 912 break; 913 case BinaryOperator::Mul: 914 case BinaryOperator::MulAssign: 915 OpID = 3; 916 IID = llvm::Intrinsic::smul_with_overflow; 917 break; 918 default: 919 assert(false && "Unsupported operation for overflow detection"); 920 IID = 0; 921 } 922 OpID <<= 1; 923 OpID |= 1; 924 925 const llvm::Type *opTy = CGF.CGM.getTypes().ConvertType(Ops.Ty); 926 927 llvm::Function *intrinsic = CGF.CGM.getIntrinsic(IID, &opTy, 1); 928 929 Value *resultAndOverflow = Builder.CreateCall2(intrinsic, Ops.LHS, Ops.RHS); 930 Value *result = Builder.CreateExtractValue(resultAndOverflow, 0); 931 Value *overflow = Builder.CreateExtractValue(resultAndOverflow, 1); 932 933 // Branch in case of overflow. 934 llvm::BasicBlock *initialBB = Builder.GetInsertBlock(); 935 llvm::BasicBlock *overflowBB = 936 CGF.createBasicBlock("overflow", CGF.CurFn); 937 llvm::BasicBlock *continueBB = 938 CGF.createBasicBlock("overflow.continue", CGF.CurFn); 939 940 Builder.CreateCondBr(overflow, overflowBB, continueBB); 941 942 // Handle overflow 943 944 Builder.SetInsertPoint(overflowBB); 945 946 // Handler is: 947 // long long *__overflow_handler)(long long a, long long b, char op, 948 // char width) 949 std::vector<const llvm::Type*> handerArgTypes; 950 handerArgTypes.push_back(llvm::Type::Int64Ty); 951 handerArgTypes.push_back(llvm::Type::Int64Ty); 952 handerArgTypes.push_back(llvm::Type::Int8Ty); 953 handerArgTypes.push_back(llvm::Type::Int8Ty); 954 llvm::FunctionType *handlerTy = llvm::FunctionType::get(llvm::Type::Int64Ty, 955 handerArgTypes, false); 956 llvm::Value *handlerFunction = 957 CGF.CGM.getModule().getOrInsertGlobal("__overflow_handler", 958 llvm::PointerType::getUnqual(handlerTy)); 959 handlerFunction = Builder.CreateLoad(handlerFunction); 960 961 llvm::Value *handlerResult = Builder.CreateCall4(handlerFunction, 962 Builder.CreateSExt(Ops.LHS, llvm::Type::Int64Ty), 963 Builder.CreateSExt(Ops.RHS, llvm::Type::Int64Ty), 964 llvm::ConstantInt::get(llvm::Type::Int8Ty, OpID), 965 llvm::ConstantInt::get(llvm::Type::Int8Ty, 966 cast<llvm::IntegerType>(opTy)->getBitWidth())); 967 968 handlerResult = Builder.CreateTrunc(handlerResult, opTy); 969 970 Builder.CreateBr(continueBB); 971 972 // Set up the continuation 973 Builder.SetInsertPoint(continueBB); 974 // Get the correct result 975 llvm::PHINode *phi = Builder.CreatePHI(opTy); 976 phi->reserveOperandSpace(2); 977 phi->addIncoming(result, initialBB); 978 phi->addIncoming(handlerResult, overflowBB); 979 980 return phi; 981} 982 983Value *ScalarExprEmitter::EmitAdd(const BinOpInfo &Ops) { 984 if (!Ops.Ty->isPointerType()) { 985 if (CGF.getContext().getLangOptions().OverflowChecking 986 && Ops.Ty->isSignedIntegerType()) 987 return EmitOverflowCheckedBinOp(Ops); 988 return Builder.CreateAdd(Ops.LHS, Ops.RHS, "add"); 989 } 990 991 if (Ops.Ty->getAsPointerType()->isVariableArrayType()) { 992 // The amount of the addition needs to account for the VLA size 993 CGF.ErrorUnsupported(Ops.E, "VLA pointer addition"); 994 } 995 Value *Ptr, *Idx; 996 Expr *IdxExp; 997 const PointerType *PT; 998 if ((PT = Ops.E->getLHS()->getType()->getAsPointerType())) { 999 Ptr = Ops.LHS; 1000 Idx = Ops.RHS; 1001 IdxExp = Ops.E->getRHS(); 1002 } else { // int + pointer 1003 PT = Ops.E->getRHS()->getType()->getAsPointerType(); 1004 assert(PT && "Invalid add expr"); 1005 Ptr = Ops.RHS; 1006 Idx = Ops.LHS; 1007 IdxExp = Ops.E->getLHS(); 1008 } 1009 1010 unsigned Width = cast<llvm::IntegerType>(Idx->getType())->getBitWidth(); 1011 if (Width < CGF.LLVMPointerWidth) { 1012 // Zero or sign extend the pointer value based on whether the index is 1013 // signed or not. 1014 const llvm::Type *IdxType = llvm::IntegerType::get(CGF.LLVMPointerWidth); 1015 if (IdxExp->getType()->isSignedIntegerType()) 1016 Idx = Builder.CreateSExt(Idx, IdxType, "idx.ext"); 1017 else 1018 Idx = Builder.CreateZExt(Idx, IdxType, "idx.ext"); 1019 } 1020 1021 const QualType ElementType = PT->getPointeeType(); 1022 // Handle interface types, which are not represented with a concrete 1023 // type. 1024 if (const ObjCInterfaceType *OIT = dyn_cast<ObjCInterfaceType>(ElementType)) { 1025 llvm::Value *InterfaceSize = 1026 llvm::ConstantInt::get(Idx->getType(), 1027 CGF.getContext().getTypeSize(OIT) / 8); 1028 Idx = Builder.CreateMul(Idx, InterfaceSize); 1029 const llvm::Type *i8Ty = llvm::PointerType::getUnqual(llvm::Type::Int8Ty); 1030 Value *Casted = Builder.CreateBitCast(Ptr, i8Ty); 1031 Value *Res = Builder.CreateGEP(Casted, Idx, "add.ptr"); 1032 return Builder.CreateBitCast(Res, Ptr->getType()); 1033 } 1034 1035 // Explicitly handle GNU void* and function pointer arithmetic 1036 // extensions. The GNU void* casts amount to no-ops since our void* 1037 // type is i8*, but this is future proof. 1038 if (ElementType->isVoidType() || ElementType->isFunctionType()) { 1039 const llvm::Type *i8Ty = llvm::PointerType::getUnqual(llvm::Type::Int8Ty); 1040 Value *Casted = Builder.CreateBitCast(Ptr, i8Ty); 1041 Value *Res = Builder.CreateGEP(Casted, Idx, "add.ptr"); 1042 return Builder.CreateBitCast(Res, Ptr->getType()); 1043 } 1044 1045 return Builder.CreateGEP(Ptr, Idx, "add.ptr"); 1046} 1047 1048Value *ScalarExprEmitter::EmitSub(const BinOpInfo &Ops) { 1049 if (!isa<llvm::PointerType>(Ops.LHS->getType())) { 1050 if (CGF.getContext().getLangOptions().OverflowChecking 1051 && Ops.Ty->isSignedIntegerType()) 1052 return EmitOverflowCheckedBinOp(Ops); 1053 return Builder.CreateSub(Ops.LHS, Ops.RHS, "sub"); 1054 } 1055 1056 if (Ops.E->getLHS()->getType()->getAsPointerType()->isVariableArrayType()) { 1057 // The amount of the addition needs to account for the VLA size for 1058 // ptr-int 1059 // The amount of the division needs to account for the VLA size for 1060 // ptr-ptr. 1061 CGF.ErrorUnsupported(Ops.E, "VLA pointer subtraction"); 1062 } 1063 1064 const QualType LHSType = Ops.E->getLHS()->getType(); 1065 const QualType LHSElementType = LHSType->getAsPointerType()->getPointeeType(); 1066 if (!isa<llvm::PointerType>(Ops.RHS->getType())) { 1067 // pointer - int 1068 Value *Idx = Ops.RHS; 1069 unsigned Width = cast<llvm::IntegerType>(Idx->getType())->getBitWidth(); 1070 if (Width < CGF.LLVMPointerWidth) { 1071 // Zero or sign extend the pointer value based on whether the index is 1072 // signed or not. 1073 const llvm::Type *IdxType = llvm::IntegerType::get(CGF.LLVMPointerWidth); 1074 if (Ops.E->getRHS()->getType()->isSignedIntegerType()) 1075 Idx = Builder.CreateSExt(Idx, IdxType, "idx.ext"); 1076 else 1077 Idx = Builder.CreateZExt(Idx, IdxType, "idx.ext"); 1078 } 1079 Idx = Builder.CreateNeg(Idx, "sub.ptr.neg"); 1080 1081 // Handle interface types, which are not represented with a concrete 1082 // type. 1083 if (const ObjCInterfaceType *OIT = 1084 dyn_cast<ObjCInterfaceType>(LHSElementType)) { 1085 llvm::Value *InterfaceSize = 1086 llvm::ConstantInt::get(Idx->getType(), 1087 CGF.getContext().getTypeSize(OIT) / 8); 1088 Idx = Builder.CreateMul(Idx, InterfaceSize); 1089 const llvm::Type *i8Ty = llvm::PointerType::getUnqual(llvm::Type::Int8Ty); 1090 Value *LHSCasted = Builder.CreateBitCast(Ops.LHS, i8Ty); 1091 Value *Res = Builder.CreateGEP(LHSCasted, Idx, "add.ptr"); 1092 return Builder.CreateBitCast(Res, Ops.LHS->getType()); 1093 } 1094 1095 // Explicitly handle GNU void* and function pointer arithmetic 1096 // extensions. The GNU void* casts amount to no-ops since our 1097 // void* type is i8*, but this is future proof. 1098 if (LHSElementType->isVoidType() || LHSElementType->isFunctionType()) { 1099 const llvm::Type *i8Ty = llvm::PointerType::getUnqual(llvm::Type::Int8Ty); 1100 Value *LHSCasted = Builder.CreateBitCast(Ops.LHS, i8Ty); 1101 Value *Res = Builder.CreateGEP(LHSCasted, Idx, "sub.ptr"); 1102 return Builder.CreateBitCast(Res, Ops.LHS->getType()); 1103 } 1104 1105 return Builder.CreateGEP(Ops.LHS, Idx, "sub.ptr"); 1106 } else { 1107 // pointer - pointer 1108 Value *LHS = Ops.LHS; 1109 Value *RHS = Ops.RHS; 1110 1111 uint64_t ElementSize; 1112 1113 // Handle GCC extension for pointer arithmetic on void* and function pointer 1114 // types. 1115 if (LHSElementType->isVoidType() || LHSElementType->isFunctionType()) { 1116 ElementSize = 1; 1117 } else { 1118 ElementSize = CGF.getContext().getTypeSize(LHSElementType) / 8; 1119 } 1120 1121 const llvm::Type *ResultType = ConvertType(Ops.Ty); 1122 LHS = Builder.CreatePtrToInt(LHS, ResultType, "sub.ptr.lhs.cast"); 1123 RHS = Builder.CreatePtrToInt(RHS, ResultType, "sub.ptr.rhs.cast"); 1124 Value *BytesBetween = Builder.CreateSub(LHS, RHS, "sub.ptr.sub"); 1125 1126 // Optimize out the shift for element size of 1. 1127 if (ElementSize == 1) 1128 return BytesBetween; 1129 1130 // HACK: LLVM doesn't have an divide instruction that 'knows' there is no 1131 // remainder. As such, we handle common power-of-two cases here to generate 1132 // better code. See PR2247. 1133 if (llvm::isPowerOf2_64(ElementSize)) { 1134 Value *ShAmt = 1135 llvm::ConstantInt::get(ResultType, llvm::Log2_64(ElementSize)); 1136 return Builder.CreateAShr(BytesBetween, ShAmt, "sub.ptr.shr"); 1137 } 1138 1139 // Otherwise, do a full sdiv. 1140 Value *BytesPerElt = llvm::ConstantInt::get(ResultType, ElementSize); 1141 return Builder.CreateSDiv(BytesBetween, BytesPerElt, "sub.ptr.div"); 1142 } 1143} 1144 1145Value *ScalarExprEmitter::EmitShl(const BinOpInfo &Ops) { 1146 // LLVM requires the LHS and RHS to be the same type: promote or truncate the 1147 // RHS to the same size as the LHS. 1148 Value *RHS = Ops.RHS; 1149 if (Ops.LHS->getType() != RHS->getType()) 1150 RHS = Builder.CreateIntCast(RHS, Ops.LHS->getType(), false, "sh_prom"); 1151 1152 return Builder.CreateShl(Ops.LHS, RHS, "shl"); 1153} 1154 1155Value *ScalarExprEmitter::EmitShr(const BinOpInfo &Ops) { 1156 // LLVM requires the LHS and RHS to be the same type: promote or truncate the 1157 // RHS to the same size as the LHS. 1158 Value *RHS = Ops.RHS; 1159 if (Ops.LHS->getType() != RHS->getType()) 1160 RHS = Builder.CreateIntCast(RHS, Ops.LHS->getType(), false, "sh_prom"); 1161 1162 if (Ops.Ty->isUnsignedIntegerType()) 1163 return Builder.CreateLShr(Ops.LHS, RHS, "shr"); 1164 return Builder.CreateAShr(Ops.LHS, RHS, "shr"); 1165} 1166 1167Value *ScalarExprEmitter::EmitCompare(const BinaryOperator *E,unsigned UICmpOpc, 1168 unsigned SICmpOpc, unsigned FCmpOpc) { 1169 TestAndClearIgnoreResultAssign(); 1170 Value *Result; 1171 QualType LHSTy = E->getLHS()->getType(); 1172 if (!LHSTy->isAnyComplexType() && !LHSTy->isVectorType()) { 1173 Value *LHS = Visit(E->getLHS()); 1174 Value *RHS = Visit(E->getRHS()); 1175 1176 if (LHS->getType()->isFloatingPoint()) { 1177 Result = Builder.CreateFCmp((llvm::CmpInst::Predicate)FCmpOpc, 1178 LHS, RHS, "cmp"); 1179 } else if (LHSTy->isSignedIntegerType()) { 1180 Result = Builder.CreateICmp((llvm::ICmpInst::Predicate)SICmpOpc, 1181 LHS, RHS, "cmp"); 1182 } else { 1183 // Unsigned integers and pointers. 1184 Result = Builder.CreateICmp((llvm::ICmpInst::Predicate)UICmpOpc, 1185 LHS, RHS, "cmp"); 1186 } 1187 } else if (LHSTy->isVectorType()) { 1188 Value *LHS = Visit(E->getLHS()); 1189 Value *RHS = Visit(E->getRHS()); 1190 1191 if (LHS->getType()->isFPOrFPVector()) { 1192 Result = Builder.CreateVFCmp((llvm::CmpInst::Predicate)FCmpOpc, 1193 LHS, RHS, "cmp"); 1194 } else if (LHSTy->isUnsignedIntegerType()) { 1195 Result = Builder.CreateVICmp((llvm::CmpInst::Predicate)UICmpOpc, 1196 LHS, RHS, "cmp"); 1197 } else { 1198 // Signed integers and pointers. 1199 Result = Builder.CreateVICmp((llvm::CmpInst::Predicate)SICmpOpc, 1200 LHS, RHS, "cmp"); 1201 } 1202 return Result; 1203 } else { 1204 // Complex Comparison: can only be an equality comparison. 1205 CodeGenFunction::ComplexPairTy LHS = CGF.EmitComplexExpr(E->getLHS()); 1206 CodeGenFunction::ComplexPairTy RHS = CGF.EmitComplexExpr(E->getRHS()); 1207 1208 QualType CETy = LHSTy->getAsComplexType()->getElementType(); 1209 1210 Value *ResultR, *ResultI; 1211 if (CETy->isRealFloatingType()) { 1212 ResultR = Builder.CreateFCmp((llvm::FCmpInst::Predicate)FCmpOpc, 1213 LHS.first, RHS.first, "cmp.r"); 1214 ResultI = Builder.CreateFCmp((llvm::FCmpInst::Predicate)FCmpOpc, 1215 LHS.second, RHS.second, "cmp.i"); 1216 } else { 1217 // Complex comparisons can only be equality comparisons. As such, signed 1218 // and unsigned opcodes are the same. 1219 ResultR = Builder.CreateICmp((llvm::ICmpInst::Predicate)UICmpOpc, 1220 LHS.first, RHS.first, "cmp.r"); 1221 ResultI = Builder.CreateICmp((llvm::ICmpInst::Predicate)UICmpOpc, 1222 LHS.second, RHS.second, "cmp.i"); 1223 } 1224 1225 if (E->getOpcode() == BinaryOperator::EQ) { 1226 Result = Builder.CreateAnd(ResultR, ResultI, "and.ri"); 1227 } else { 1228 assert(E->getOpcode() == BinaryOperator::NE && 1229 "Complex comparison other than == or != ?"); 1230 Result = Builder.CreateOr(ResultR, ResultI, "or.ri"); 1231 } 1232 } 1233 1234 return EmitScalarConversion(Result, CGF.getContext().BoolTy, E->getType()); 1235} 1236 1237Value *ScalarExprEmitter::VisitBinAssign(const BinaryOperator *E) { 1238 bool Ignore = TestAndClearIgnoreResultAssign(); 1239 1240 // __block variables need to have the rhs evaluated first, plus this should 1241 // improve codegen just a little. 1242 Value *RHS = Visit(E->getRHS()); 1243 LValue LHS = EmitLValue(E->getLHS()); 1244 1245 // Store the value into the LHS. Bit-fields are handled specially 1246 // because the result is altered by the store, i.e., [C99 6.5.16p1] 1247 // 'An assignment expression has the value of the left operand after 1248 // the assignment...'. 1249 if (LHS.isBitfield()) { 1250 if (!LHS.isVolatileQualified()) { 1251 CGF.EmitStoreThroughBitfieldLValue(RValue::get(RHS), LHS, E->getType(), 1252 &RHS); 1253 return RHS; 1254 } else 1255 CGF.EmitStoreThroughBitfieldLValue(RValue::get(RHS), LHS, E->getType()); 1256 } else 1257 CGF.EmitStoreThroughLValue(RValue::get(RHS), LHS, E->getType()); 1258 if (Ignore) 1259 return 0; 1260 return EmitLoadOfLValue(LHS, E->getType()); 1261} 1262 1263Value *ScalarExprEmitter::VisitBinLAnd(const BinaryOperator *E) { 1264 // If we have 0 && RHS, see if we can elide RHS, if so, just return 0. 1265 // If we have 1 && X, just emit X without inserting the control flow. 1266 if (int Cond = CGF.ConstantFoldsToSimpleInteger(E->getLHS())) { 1267 if (Cond == 1) { // If we have 1 && X, just emit X. 1268 Value *RHSCond = CGF.EvaluateExprAsBool(E->getRHS()); 1269 // ZExt result to int. 1270 return Builder.CreateZExt(RHSCond, CGF.LLVMIntTy, "land.ext"); 1271 } 1272 1273 // 0 && RHS: If it is safe, just elide the RHS, and return 0. 1274 if (!CGF.ContainsLabel(E->getRHS())) 1275 return llvm::Constant::getNullValue(CGF.LLVMIntTy); 1276 } 1277 1278 llvm::BasicBlock *ContBlock = CGF.createBasicBlock("land.end"); 1279 llvm::BasicBlock *RHSBlock = CGF.createBasicBlock("land.rhs"); 1280 1281 // Branch on the LHS first. If it is false, go to the failure (cont) block. 1282 CGF.EmitBranchOnBoolExpr(E->getLHS(), RHSBlock, ContBlock); 1283 1284 // Any edges into the ContBlock are now from an (indeterminate number of) 1285 // edges from this first condition. All of these values will be false. Start 1286 // setting up the PHI node in the Cont Block for this. 1287 llvm::PHINode *PN = llvm::PHINode::Create(llvm::Type::Int1Ty, "", ContBlock); 1288 PN->reserveOperandSpace(2); // Normal case, two inputs. 1289 for (llvm::pred_iterator PI = pred_begin(ContBlock), PE = pred_end(ContBlock); 1290 PI != PE; ++PI) 1291 PN->addIncoming(llvm::ConstantInt::getFalse(), *PI); 1292 1293 CGF.PushConditionalTempDestruction(); 1294 CGF.EmitBlock(RHSBlock); 1295 Value *RHSCond = CGF.EvaluateExprAsBool(E->getRHS()); 1296 CGF.PopConditionalTempDestruction(); 1297 1298 // Reaquire the RHS block, as there may be subblocks inserted. 1299 RHSBlock = Builder.GetInsertBlock(); 1300 1301 // Emit an unconditional branch from this block to ContBlock. Insert an entry 1302 // into the phi node for the edge with the value of RHSCond. 1303 CGF.EmitBlock(ContBlock); 1304 PN->addIncoming(RHSCond, RHSBlock); 1305 1306 // ZExt result to int. 1307 return Builder.CreateZExt(PN, CGF.LLVMIntTy, "land.ext"); 1308} 1309 1310Value *ScalarExprEmitter::VisitBinLOr(const BinaryOperator *E) { 1311 // If we have 1 || RHS, see if we can elide RHS, if so, just return 1. 1312 // If we have 0 || X, just emit X without inserting the control flow. 1313 if (int Cond = CGF.ConstantFoldsToSimpleInteger(E->getLHS())) { 1314 if (Cond == -1) { // If we have 0 || X, just emit X. 1315 Value *RHSCond = CGF.EvaluateExprAsBool(E->getRHS()); 1316 // ZExt result to int. 1317 return Builder.CreateZExt(RHSCond, CGF.LLVMIntTy, "lor.ext"); 1318 } 1319 1320 // 1 || RHS: If it is safe, just elide the RHS, and return 1. 1321 if (!CGF.ContainsLabel(E->getRHS())) 1322 return llvm::ConstantInt::get(CGF.LLVMIntTy, 1); 1323 } 1324 1325 llvm::BasicBlock *ContBlock = CGF.createBasicBlock("lor.end"); 1326 llvm::BasicBlock *RHSBlock = CGF.createBasicBlock("lor.rhs"); 1327 1328 // Branch on the LHS first. If it is true, go to the success (cont) block. 1329 CGF.EmitBranchOnBoolExpr(E->getLHS(), ContBlock, RHSBlock); 1330 1331 // Any edges into the ContBlock are now from an (indeterminate number of) 1332 // edges from this first condition. All of these values will be true. Start 1333 // setting up the PHI node in the Cont Block for this. 1334 llvm::PHINode *PN = llvm::PHINode::Create(llvm::Type::Int1Ty, "", ContBlock); 1335 PN->reserveOperandSpace(2); // Normal case, two inputs. 1336 for (llvm::pred_iterator PI = pred_begin(ContBlock), PE = pred_end(ContBlock); 1337 PI != PE; ++PI) 1338 PN->addIncoming(llvm::ConstantInt::getTrue(), *PI); 1339 1340 CGF.PushConditionalTempDestruction(); 1341 1342 // Emit the RHS condition as a bool value. 1343 CGF.EmitBlock(RHSBlock); 1344 Value *RHSCond = CGF.EvaluateExprAsBool(E->getRHS()); 1345 1346 CGF.PopConditionalTempDestruction(); 1347 1348 // Reaquire the RHS block, as there may be subblocks inserted. 1349 RHSBlock = Builder.GetInsertBlock(); 1350 1351 // Emit an unconditional branch from this block to ContBlock. Insert an entry 1352 // into the phi node for the edge with the value of RHSCond. 1353 CGF.EmitBlock(ContBlock); 1354 PN->addIncoming(RHSCond, RHSBlock); 1355 1356 // ZExt result to int. 1357 return Builder.CreateZExt(PN, CGF.LLVMIntTy, "lor.ext"); 1358} 1359 1360Value *ScalarExprEmitter::VisitBinComma(const BinaryOperator *E) { 1361 CGF.EmitStmt(E->getLHS()); 1362 CGF.EnsureInsertPoint(); 1363 return Visit(E->getRHS()); 1364} 1365 1366//===----------------------------------------------------------------------===// 1367// Other Operators 1368//===----------------------------------------------------------------------===// 1369 1370/// isCheapEnoughToEvaluateUnconditionally - Return true if the specified 1371/// expression is cheap enough and side-effect-free enough to evaluate 1372/// unconditionally instead of conditionally. This is used to convert control 1373/// flow into selects in some cases. 1374static bool isCheapEnoughToEvaluateUnconditionally(const Expr *E) { 1375 if (const ParenExpr *PE = dyn_cast<ParenExpr>(E)) 1376 return isCheapEnoughToEvaluateUnconditionally(PE->getSubExpr()); 1377 1378 // TODO: Allow anything we can constant fold to an integer or fp constant. 1379 if (isa<IntegerLiteral>(E) || isa<CharacterLiteral>(E) || 1380 isa<FloatingLiteral>(E)) 1381 return true; 1382 1383 // Non-volatile automatic variables too, to get "cond ? X : Y" where 1384 // X and Y are local variables. 1385 if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(E)) 1386 if (const VarDecl *VD = dyn_cast<VarDecl>(DRE->getDecl())) 1387 if (VD->hasLocalStorage() && !VD->getType().isVolatileQualified()) 1388 return true; 1389 1390 return false; 1391} 1392 1393 1394Value *ScalarExprEmitter:: 1395VisitConditionalOperator(const ConditionalOperator *E) { 1396 TestAndClearIgnoreResultAssign(); 1397 // If the condition constant folds and can be elided, try to avoid emitting 1398 // the condition and the dead arm. 1399 if (int Cond = CGF.ConstantFoldsToSimpleInteger(E->getCond())){ 1400 Expr *Live = E->getLHS(), *Dead = E->getRHS(); 1401 if (Cond == -1) 1402 std::swap(Live, Dead); 1403 1404 // If the dead side doesn't have labels we need, and if the Live side isn't 1405 // the gnu missing ?: extension (which we could handle, but don't bother 1406 // to), just emit the Live part. 1407 if ((!Dead || !CGF.ContainsLabel(Dead)) && // No labels in dead part 1408 Live) // Live part isn't missing. 1409 return Visit(Live); 1410 } 1411 1412 1413 // If this is a really simple expression (like x ? 4 : 5), emit this as a 1414 // select instead of as control flow. We can only do this if it is cheap and 1415 // safe to evaluate the LHS and RHS unconditionally. 1416 if (E->getLHS() && isCheapEnoughToEvaluateUnconditionally(E->getLHS()) && 1417 isCheapEnoughToEvaluateUnconditionally(E->getRHS())) { 1418 llvm::Value *CondV = CGF.EvaluateExprAsBool(E->getCond()); 1419 llvm::Value *LHS = Visit(E->getLHS()); 1420 llvm::Value *RHS = Visit(E->getRHS()); 1421 return Builder.CreateSelect(CondV, LHS, RHS, "cond"); 1422 } 1423 1424 1425 llvm::BasicBlock *LHSBlock = CGF.createBasicBlock("cond.true"); 1426 llvm::BasicBlock *RHSBlock = CGF.createBasicBlock("cond.false"); 1427 llvm::BasicBlock *ContBlock = CGF.createBasicBlock("cond.end"); 1428 Value *CondVal = 0; 1429 1430 // If we don't have the GNU missing condition extension, emit a branch on 1431 // bool the normal way. 1432 if (E->getLHS()) { 1433 // Otherwise, just use EmitBranchOnBoolExpr to get small and simple code for 1434 // the branch on bool. 1435 CGF.EmitBranchOnBoolExpr(E->getCond(), LHSBlock, RHSBlock); 1436 } else { 1437 // Otherwise, for the ?: extension, evaluate the conditional and then 1438 // convert it to bool the hard way. We do this explicitly because we need 1439 // the unconverted value for the missing middle value of the ?:. 1440 CondVal = CGF.EmitScalarExpr(E->getCond()); 1441 1442 // In some cases, EmitScalarConversion will delete the "CondVal" expression 1443 // if there are no extra uses (an optimization). Inhibit this by making an 1444 // extra dead use, because we're going to add a use of CondVal later. We 1445 // don't use the builder for this, because we don't want it to get optimized 1446 // away. This leaves dead code, but the ?: extension isn't common. 1447 new llvm::BitCastInst(CondVal, CondVal->getType(), "dummy?:holder", 1448 Builder.GetInsertBlock()); 1449 1450 Value *CondBoolVal = 1451 CGF.EmitScalarConversion(CondVal, E->getCond()->getType(), 1452 CGF.getContext().BoolTy); 1453 Builder.CreateCondBr(CondBoolVal, LHSBlock, RHSBlock); 1454 } 1455 1456 CGF.PushConditionalTempDestruction(); 1457 CGF.EmitBlock(LHSBlock); 1458 1459 // Handle the GNU extension for missing LHS. 1460 Value *LHS; 1461 if (E->getLHS()) 1462 LHS = Visit(E->getLHS()); 1463 else // Perform promotions, to handle cases like "short ?: int" 1464 LHS = EmitScalarConversion(CondVal, E->getCond()->getType(), E->getType()); 1465 1466 CGF.PopConditionalTempDestruction(); 1467 LHSBlock = Builder.GetInsertBlock(); 1468 CGF.EmitBranch(ContBlock); 1469 1470 CGF.PushConditionalTempDestruction(); 1471 CGF.EmitBlock(RHSBlock); 1472 1473 Value *RHS = Visit(E->getRHS()); 1474 CGF.PopConditionalTempDestruction(); 1475 RHSBlock = Builder.GetInsertBlock(); 1476 CGF.EmitBranch(ContBlock); 1477 1478 CGF.EmitBlock(ContBlock); 1479 1480 if (!LHS || !RHS) { 1481 assert(E->getType()->isVoidType() && "Non-void value should have a value"); 1482 return 0; 1483 } 1484 1485 // Create a PHI node for the real part. 1486 llvm::PHINode *PN = Builder.CreatePHI(LHS->getType(), "cond"); 1487 PN->reserveOperandSpace(2); 1488 PN->addIncoming(LHS, LHSBlock); 1489 PN->addIncoming(RHS, RHSBlock); 1490 return PN; 1491} 1492 1493Value *ScalarExprEmitter::VisitChooseExpr(ChooseExpr *E) { 1494 return Visit(E->getChosenSubExpr(CGF.getContext())); 1495} 1496 1497Value *ScalarExprEmitter::VisitVAArgExpr(VAArgExpr *VE) { 1498 llvm::Value *ArgValue = CGF.EmitVAListRef(VE->getSubExpr()); 1499 llvm::Value *ArgPtr = CGF.EmitVAArg(ArgValue, VE->getType()); 1500 1501 // If EmitVAArg fails, we fall back to the LLVM instruction. 1502 if (!ArgPtr) 1503 return Builder.CreateVAArg(ArgValue, ConvertType(VE->getType())); 1504 1505 // FIXME Volatility. 1506 return Builder.CreateLoad(ArgPtr); 1507} 1508 1509Value *ScalarExprEmitter::VisitBlockExpr(const BlockExpr *BE) { 1510 return CGF.BuildBlockLiteralTmp(BE); 1511} 1512 1513//===----------------------------------------------------------------------===// 1514// Entry Point into this File 1515//===----------------------------------------------------------------------===// 1516 1517/// EmitScalarExpr - Emit the computation of the specified expression of 1518/// scalar type, ignoring the result. 1519Value *CodeGenFunction::EmitScalarExpr(const Expr *E, bool IgnoreResultAssign) { 1520 assert(E && !hasAggregateLLVMType(E->getType()) && 1521 "Invalid scalar expression to emit"); 1522 1523 return ScalarExprEmitter(*this, IgnoreResultAssign) 1524 .Visit(const_cast<Expr*>(E)); 1525} 1526 1527/// EmitScalarConversion - Emit a conversion from the specified type to the 1528/// specified destination type, both of which are LLVM scalar types. 1529Value *CodeGenFunction::EmitScalarConversion(Value *Src, QualType SrcTy, 1530 QualType DstTy) { 1531 assert(!hasAggregateLLVMType(SrcTy) && !hasAggregateLLVMType(DstTy) && 1532 "Invalid scalar expression to emit"); 1533 return ScalarExprEmitter(*this).EmitScalarConversion(Src, SrcTy, DstTy); 1534} 1535 1536/// EmitComplexToScalarConversion - Emit a conversion from the specified 1537/// complex type to the specified destination type, where the destination 1538/// type is an LLVM scalar type. 1539Value *CodeGenFunction::EmitComplexToScalarConversion(ComplexPairTy Src, 1540 QualType SrcTy, 1541 QualType DstTy) { 1542 assert(SrcTy->isAnyComplexType() && !hasAggregateLLVMType(DstTy) && 1543 "Invalid complex -> scalar conversion"); 1544 return ScalarExprEmitter(*this).EmitComplexToScalarConversion(Src, SrcTy, 1545 DstTy); 1546} 1547 1548Value *CodeGenFunction::EmitShuffleVector(Value* V1, Value *V2, ...) { 1549 assert(V1->getType() == V2->getType() && 1550 "Vector operands must be of the same type"); 1551 unsigned NumElements = 1552 cast<llvm::VectorType>(V1->getType())->getNumElements(); 1553 1554 va_list va; 1555 va_start(va, V2); 1556 1557 llvm::SmallVector<llvm::Constant*, 16> Args; 1558 for (unsigned i = 0; i < NumElements; i++) { 1559 int n = va_arg(va, int); 1560 assert(n >= 0 && n < (int)NumElements * 2 && 1561 "Vector shuffle index out of bounds!"); 1562 Args.push_back(llvm::ConstantInt::get(llvm::Type::Int32Ty, n)); 1563 } 1564 1565 const char *Name = va_arg(va, const char *); 1566 va_end(va); 1567 1568 llvm::Constant *Mask = llvm::ConstantVector::get(&Args[0], NumElements); 1569 1570 return Builder.CreateShuffleVector(V1, V2, Mask, Name); 1571} 1572 1573llvm::Value *CodeGenFunction::EmitVector(llvm::Value * const *Vals, 1574 unsigned NumVals, bool isSplat) { 1575 llvm::Value *Vec 1576 = llvm::UndefValue::get(llvm::VectorType::get(Vals[0]->getType(), NumVals)); 1577 1578 for (unsigned i = 0, e = NumVals; i != e; ++i) { 1579 llvm::Value *Val = isSplat ? Vals[0] : Vals[i]; 1580 llvm::Value *Idx = llvm::ConstantInt::get(llvm::Type::Int32Ty, i); 1581 Vec = Builder.CreateInsertElement(Vec, Val, Idx, "tmp"); 1582 } 1583 1584 return Vec; 1585} 1586