CGExprScalar.cpp revision 69243825cb5c91ec7207256aa57ae327cfaf8cb2
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; 52public: 53 54 ScalarExprEmitter(CodeGenFunction &cgf, bool ira=false) 55 : CGF(cgf), Builder(CGF.Builder), IgnoreResultAssign(ira) { 56 } 57 58 //===--------------------------------------------------------------------===// 59 // Utilities 60 //===--------------------------------------------------------------------===// 61 62 bool TestAndClearIgnoreResultAssign() { 63 bool I = IgnoreResultAssign; 64 IgnoreResultAssign = false; 65 return I; 66 } 67 68 const llvm::Type *ConvertType(QualType T) { return CGF.ConvertType(T); } 69 LValue EmitLValue(const Expr *E) { return CGF.EmitLValue(E); } 70 71 Value *EmitLoadOfLValue(LValue LV, QualType T) { 72 return CGF.EmitLoadOfLValue(LV, T).getScalarVal(); 73 } 74 75 /// EmitLoadOfLValue - Given an expression with complex type that represents a 76 /// value l-value, this method emits the address of the l-value, then loads 77 /// and returns the result. 78 Value *EmitLoadOfLValue(const Expr *E) { 79 return EmitLoadOfLValue(EmitLValue(E), E->getType()); 80 } 81 82 /// EmitConversionToBool - Convert the specified expression value to a 83 /// boolean (i1) truth value. This is equivalent to "Val != 0". 84 Value *EmitConversionToBool(Value *Src, QualType DstTy); 85 86 /// EmitScalarConversion - Emit a conversion from the specified type to the 87 /// specified destination type, both of which are LLVM scalar types. 88 Value *EmitScalarConversion(Value *Src, QualType SrcTy, QualType DstTy); 89 90 /// EmitComplexToScalarConversion - Emit a conversion from the specified 91 /// complex type to the specified destination type, where the destination 92 /// type is an LLVM scalar type. 93 Value *EmitComplexToScalarConversion(CodeGenFunction::ComplexPairTy Src, 94 QualType SrcTy, QualType DstTy); 95 96 //===--------------------------------------------------------------------===// 97 // Visitor Methods 98 //===--------------------------------------------------------------------===// 99 100 Value *VisitStmt(Stmt *S) { 101 S->dump(CGF.getContext().getSourceManager()); 102 assert(0 && "Stmt can't have complex result type!"); 103 return 0; 104 } 105 Value *VisitExpr(Expr *S); 106 Value *VisitParenExpr(ParenExpr *PE) { return Visit(PE->getSubExpr()); } 107 108 // Leaves. 109 Value *VisitIntegerLiteral(const IntegerLiteral *E) { 110 return llvm::ConstantInt::get(E->getValue()); 111 } 112 Value *VisitFloatingLiteral(const FloatingLiteral *E) { 113 return llvm::ConstantFP::get(E->getValue()); 114 } 115 Value *VisitCharacterLiteral(const CharacterLiteral *E) { 116 return llvm::ConstantInt::get(ConvertType(E->getType()), E->getValue()); 117 } 118 Value *VisitCXXBoolLiteralExpr(const CXXBoolLiteralExpr *E) { 119 return llvm::ConstantInt::get(ConvertType(E->getType()), E->getValue()); 120 } 121 Value *VisitCXXZeroInitValueExpr(const CXXZeroInitValueExpr *E) { 122 return CGF.getLLVMContext().getNullValue(ConvertType(E->getType())); 123 } 124 Value *VisitGNUNullExpr(const GNUNullExpr *E) { 125 return CGF.getLLVMContext().getNullValue(ConvertType(E->getType())); 126 } 127 Value *VisitTypesCompatibleExpr(const TypesCompatibleExpr *E) { 128 return llvm::ConstantInt::get(ConvertType(E->getType()), 129 CGF.getContext().typesAreCompatible( 130 E->getArgType1(), E->getArgType2())); 131 } 132 Value *VisitSizeOfAlignOfExpr(const SizeOfAlignOfExpr *E); 133 Value *VisitAddrLabelExpr(const AddrLabelExpr *E) { 134 llvm::Value *V = 135 llvm::ConstantInt::get(llvm::Type::Int32Ty, 136 CGF.GetIDForAddrOfLabel(E->getLabel())); 137 138 return Builder.CreateIntToPtr(V, ConvertType(E->getType())); 139 } 140 141 // l-values. 142 Value *VisitDeclRefExpr(DeclRefExpr *E) { 143 if (const EnumConstantDecl *EC = dyn_cast<EnumConstantDecl>(E->getDecl())) 144 return llvm::ConstantInt::get(EC->getInitVal()); 145 return EmitLoadOfLValue(E); 146 } 147 Value *VisitObjCSelectorExpr(ObjCSelectorExpr *E) { 148 return CGF.EmitObjCSelectorExpr(E); 149 } 150 Value *VisitObjCProtocolExpr(ObjCProtocolExpr *E) { 151 return CGF.EmitObjCProtocolExpr(E); 152 } 153 Value *VisitObjCIvarRefExpr(ObjCIvarRefExpr *E) { 154 return EmitLoadOfLValue(E); 155 } 156 Value *VisitObjCPropertyRefExpr(ObjCPropertyRefExpr *E) { 157 return EmitLoadOfLValue(E); 158 } 159 Value *VisitObjCKVCRefExpr(ObjCKVCRefExpr *E) { 160 return EmitLoadOfLValue(E); 161 } 162 Value *VisitObjCMessageExpr(ObjCMessageExpr *E) { 163 return CGF.EmitObjCMessageExpr(E).getScalarVal(); 164 } 165 166 Value *VisitArraySubscriptExpr(ArraySubscriptExpr *E); 167 Value *VisitShuffleVectorExpr(ShuffleVectorExpr *E); 168 Value *VisitMemberExpr(Expr *E) { return EmitLoadOfLValue(E); } 169 Value *VisitExtVectorElementExpr(Expr *E) { return EmitLoadOfLValue(E); } 170 Value *VisitCompoundLiteralExpr(CompoundLiteralExpr *E) { 171 return EmitLoadOfLValue(E); 172 } 173 Value *VisitStringLiteral(Expr *E) { return EmitLValue(E).getAddress(); } 174 Value *VisitObjCEncodeExpr(const ObjCEncodeExpr *E) { 175 return EmitLValue(E).getAddress(); 176 } 177 178 Value *VisitPredefinedExpr(Expr *E) { return EmitLValue(E).getAddress(); } 179 180 Value *VisitInitListExpr(InitListExpr *E) { 181 bool Ignore = TestAndClearIgnoreResultAssign(); 182 (void)Ignore; 183 assert (Ignore == false && "init list ignored"); 184 unsigned NumInitElements = E->getNumInits(); 185 186 if (E->hadArrayRangeDesignator()) { 187 CGF.ErrorUnsupported(E, "GNU array range designator extension"); 188 } 189 190 const llvm::VectorType *VType = 191 dyn_cast<llvm::VectorType>(ConvertType(E->getType())); 192 193 // We have a scalar in braces. Just use the first element. 194 if (!VType) 195 return Visit(E->getInit(0)); 196 197 unsigned NumVectorElements = VType->getNumElements(); 198 const llvm::Type *ElementType = VType->getElementType(); 199 200 // Emit individual vector element stores. 201 llvm::Value *V = llvm::UndefValue::get(VType); 202 203 // Emit initializers 204 unsigned i; 205 for (i = 0; i < NumInitElements; ++i) { 206 Value *NewV = Visit(E->getInit(i)); 207 Value *Idx = llvm::ConstantInt::get(llvm::Type::Int32Ty, i); 208 V = Builder.CreateInsertElement(V, NewV, Idx); 209 } 210 211 // Emit remaining default initializers 212 for (/* Do not initialize i*/; i < NumVectorElements; ++i) { 213 Value *Idx = llvm::ConstantInt::get(llvm::Type::Int32Ty, i); 214 llvm::Value *NewV = CGF.getLLVMContext().getNullValue(ElementType); 215 V = Builder.CreateInsertElement(V, NewV, Idx); 216 } 217 218 return V; 219 } 220 221 Value *VisitImplicitValueInitExpr(const ImplicitValueInitExpr *E) { 222 return CGF.getLLVMContext().getNullValue(ConvertType(E->getType())); 223 } 224 Value *VisitImplicitCastExpr(const ImplicitCastExpr *E); 225 Value *VisitCastExpr(const CastExpr *E) { 226 // Make sure to evaluate VLA bounds now so that we have them for later. 227 if (E->getType()->isVariablyModifiedType()) 228 CGF.EmitVLASize(E->getType()); 229 230 return EmitCastExpr(E->getSubExpr(), E->getType()); 231 } 232 Value *EmitCastExpr(const Expr *E, QualType T); 233 234 Value *VisitCallExpr(const CallExpr *E) { 235 if (E->getCallReturnType()->isReferenceType()) 236 return EmitLoadOfLValue(E); 237 238 return CGF.EmitCallExpr(E).getScalarVal(); 239 } 240 241 Value *VisitStmtExpr(const StmtExpr *E); 242 243 Value *VisitBlockDeclRefExpr(const BlockDeclRefExpr *E); 244 245 // Unary Operators. 246 Value *VisitPrePostIncDec(const UnaryOperator *E, bool isInc, bool isPre); 247 Value *VisitUnaryPostDec(const UnaryOperator *E) { 248 return VisitPrePostIncDec(E, false, false); 249 } 250 Value *VisitUnaryPostInc(const UnaryOperator *E) { 251 return VisitPrePostIncDec(E, true, false); 252 } 253 Value *VisitUnaryPreDec(const UnaryOperator *E) { 254 return VisitPrePostIncDec(E, false, true); 255 } 256 Value *VisitUnaryPreInc(const UnaryOperator *E) { 257 return VisitPrePostIncDec(E, true, true); 258 } 259 Value *VisitUnaryAddrOf(const UnaryOperator *E) { 260 return EmitLValue(E->getSubExpr()).getAddress(); 261 } 262 Value *VisitUnaryDeref(const Expr *E) { return EmitLoadOfLValue(E); } 263 Value *VisitUnaryPlus(const UnaryOperator *E) { 264 // This differs from gcc, though, most likely due to a bug in gcc. 265 TestAndClearIgnoreResultAssign(); 266 return Visit(E->getSubExpr()); 267 } 268 Value *VisitUnaryMinus (const UnaryOperator *E); 269 Value *VisitUnaryNot (const UnaryOperator *E); 270 Value *VisitUnaryLNot (const UnaryOperator *E); 271 Value *VisitUnaryReal (const UnaryOperator *E); 272 Value *VisitUnaryImag (const UnaryOperator *E); 273 Value *VisitUnaryExtension(const UnaryOperator *E) { 274 return Visit(E->getSubExpr()); 275 } 276 Value *VisitUnaryOffsetOf(const UnaryOperator *E); 277 278 // C++ 279 Value *VisitCXXDefaultArgExpr(CXXDefaultArgExpr *DAE) { 280 return Visit(DAE->getExpr()); 281 } 282 Value *VisitCXXThisExpr(CXXThisExpr *TE) { 283 return CGF.LoadCXXThis(); 284 } 285 286 Value *VisitCXXExprWithTemporaries(CXXExprWithTemporaries *E) { 287 return CGF.EmitCXXExprWithTemporaries(E).getScalarVal(); 288 } 289 Value *VisitCXXNewExpr(const CXXNewExpr *E) { 290 return CGF.EmitCXXNewExpr(E); 291 } 292 293 // Binary Operators. 294 Value *EmitMul(const BinOpInfo &Ops) { 295 if (CGF.getContext().getLangOptions().OverflowChecking 296 && Ops.Ty->isSignedIntegerType()) 297 return EmitOverflowCheckedBinOp(Ops); 298 if (Ops.LHS->getType()->isFPOrFPVector()) 299 return Builder.CreateFMul(Ops.LHS, Ops.RHS, "mul"); 300 return Builder.CreateMul(Ops.LHS, Ops.RHS, "mul"); 301 } 302 /// Create a binary op that checks for overflow. 303 /// Currently only supports +, - and *. 304 Value *EmitOverflowCheckedBinOp(const BinOpInfo &Ops); 305 Value *EmitDiv(const BinOpInfo &Ops); 306 Value *EmitRem(const BinOpInfo &Ops); 307 Value *EmitAdd(const BinOpInfo &Ops); 308 Value *EmitSub(const BinOpInfo &Ops); 309 Value *EmitShl(const BinOpInfo &Ops); 310 Value *EmitShr(const BinOpInfo &Ops); 311 Value *EmitAnd(const BinOpInfo &Ops) { 312 return Builder.CreateAnd(Ops.LHS, Ops.RHS, "and"); 313 } 314 Value *EmitXor(const BinOpInfo &Ops) { 315 return Builder.CreateXor(Ops.LHS, Ops.RHS, "xor"); 316 } 317 Value *EmitOr (const BinOpInfo &Ops) { 318 return Builder.CreateOr(Ops.LHS, Ops.RHS, "or"); 319 } 320 321 BinOpInfo EmitBinOps(const BinaryOperator *E); 322 Value *EmitCompoundAssign(const CompoundAssignOperator *E, 323 Value *(ScalarExprEmitter::*F)(const BinOpInfo &)); 324 325 // Binary operators and binary compound assignment operators. 326#define HANDLEBINOP(OP) \ 327 Value *VisitBin ## OP(const BinaryOperator *E) { \ 328 return Emit ## OP(EmitBinOps(E)); \ 329 } \ 330 Value *VisitBin ## OP ## Assign(const CompoundAssignOperator *E) { \ 331 return EmitCompoundAssign(E, &ScalarExprEmitter::Emit ## OP); \ 332 } 333 HANDLEBINOP(Mul); 334 HANDLEBINOP(Div); 335 HANDLEBINOP(Rem); 336 HANDLEBINOP(Add); 337 HANDLEBINOP(Sub); 338 HANDLEBINOP(Shl); 339 HANDLEBINOP(Shr); 340 HANDLEBINOP(And); 341 HANDLEBINOP(Xor); 342 HANDLEBINOP(Or); 343#undef HANDLEBINOP 344 345 // Comparisons. 346 Value *EmitCompare(const BinaryOperator *E, unsigned UICmpOpc, 347 unsigned SICmpOpc, unsigned FCmpOpc); 348#define VISITCOMP(CODE, UI, SI, FP) \ 349 Value *VisitBin##CODE(const BinaryOperator *E) { \ 350 return EmitCompare(E, llvm::ICmpInst::UI, llvm::ICmpInst::SI, \ 351 llvm::FCmpInst::FP); } 352 VISITCOMP(LT, ICMP_ULT, ICMP_SLT, FCMP_OLT); 353 VISITCOMP(GT, ICMP_UGT, ICMP_SGT, FCMP_OGT); 354 VISITCOMP(LE, ICMP_ULE, ICMP_SLE, FCMP_OLE); 355 VISITCOMP(GE, ICMP_UGE, ICMP_SGE, FCMP_OGE); 356 VISITCOMP(EQ, ICMP_EQ , ICMP_EQ , FCMP_OEQ); 357 VISITCOMP(NE, ICMP_NE , ICMP_NE , FCMP_UNE); 358#undef VISITCOMP 359 360 Value *VisitBinAssign (const BinaryOperator *E); 361 362 Value *VisitBinLAnd (const BinaryOperator *E); 363 Value *VisitBinLOr (const BinaryOperator *E); 364 Value *VisitBinComma (const BinaryOperator *E); 365 366 // Other Operators. 367 Value *VisitBlockExpr(const BlockExpr *BE); 368 Value *VisitConditionalOperator(const ConditionalOperator *CO); 369 Value *VisitChooseExpr(ChooseExpr *CE); 370 Value *VisitVAArgExpr(VAArgExpr *VE); 371 Value *VisitObjCStringLiteral(const ObjCStringLiteral *E) { 372 return CGF.EmitObjCStringLiteral(E); 373 } 374}; 375} // end anonymous namespace. 376 377//===----------------------------------------------------------------------===// 378// Utilities 379//===----------------------------------------------------------------------===// 380 381/// EmitConversionToBool - Convert the specified expression value to a 382/// boolean (i1) truth value. This is equivalent to "Val != 0". 383Value *ScalarExprEmitter::EmitConversionToBool(Value *Src, QualType SrcType) { 384 assert(SrcType->isCanonical() && "EmitScalarConversion strips typedefs"); 385 386 if (SrcType->isRealFloatingType()) { 387 // Compare against 0.0 for fp scalars. 388 llvm::Value *Zero = CGF.getLLVMContext().getNullValue(Src->getType()); 389 return Builder.CreateFCmpUNE(Src, Zero, "tobool"); 390 } 391 392 assert((SrcType->isIntegerType() || isa<llvm::PointerType>(Src->getType())) && 393 "Unknown scalar type to convert"); 394 395 // Because of the type rules of C, we often end up computing a logical value, 396 // then zero extending it to int, then wanting it as a logical value again. 397 // Optimize this common case. 398 if (llvm::ZExtInst *ZI = dyn_cast<llvm::ZExtInst>(Src)) { 399 if (ZI->getOperand(0)->getType() == llvm::Type::Int1Ty) { 400 Value *Result = ZI->getOperand(0); 401 // If there aren't any more uses, zap the instruction to save space. 402 // Note that there can be more uses, for example if this 403 // is the result of an assignment. 404 if (ZI->use_empty()) 405 ZI->eraseFromParent(); 406 return Result; 407 } 408 } 409 410 // Compare against an integer or pointer null. 411 llvm::Value *Zero = CGF.getLLVMContext().getNullValue(Src->getType()); 412 return Builder.CreateICmpNE(Src, Zero, "tobool"); 413} 414 415/// EmitScalarConversion - Emit a conversion from the specified type to the 416/// specified destination type, both of which are LLVM scalar types. 417Value *ScalarExprEmitter::EmitScalarConversion(Value *Src, QualType SrcType, 418 QualType DstType) { 419 SrcType = CGF.getContext().getCanonicalType(SrcType); 420 DstType = CGF.getContext().getCanonicalType(DstType); 421 if (SrcType == DstType) return Src; 422 423 if (DstType->isVoidType()) return 0; 424 425 // Handle conversions to bool first, they are special: comparisons against 0. 426 if (DstType->isBooleanType()) 427 return EmitConversionToBool(Src, SrcType); 428 429 const llvm::Type *DstTy = ConvertType(DstType); 430 431 // Ignore conversions like int -> uint. 432 if (Src->getType() == DstTy) 433 return Src; 434 435 // Handle pointer conversions next: pointers can only be converted 436 // to/from other pointers and integers. Check for pointer types in 437 // terms of LLVM, as some native types (like Obj-C id) may map to a 438 // pointer type. 439 if (isa<llvm::PointerType>(DstTy)) { 440 // The source value may be an integer, or a pointer. 441 if (isa<llvm::PointerType>(Src->getType())) 442 return Builder.CreateBitCast(Src, DstTy, "conv"); 443 assert(SrcType->isIntegerType() && "Not ptr->ptr or int->ptr conversion?"); 444 // First, convert to the correct width so that we control the kind of 445 // extension. 446 const llvm::Type *MiddleTy = llvm::IntegerType::get(CGF.LLVMPointerWidth); 447 bool InputSigned = SrcType->isSignedIntegerType(); 448 llvm::Value* IntResult = 449 Builder.CreateIntCast(Src, MiddleTy, InputSigned, "conv"); 450 // Then, cast to pointer. 451 return Builder.CreateIntToPtr(IntResult, DstTy, "conv"); 452 } 453 454 if (isa<llvm::PointerType>(Src->getType())) { 455 // Must be an ptr to int cast. 456 assert(isa<llvm::IntegerType>(DstTy) && "not ptr->int?"); 457 return Builder.CreatePtrToInt(Src, DstTy, "conv"); 458 } 459 460 // A scalar can be splatted to an extended vector of the same element type 461 if (DstType->isExtVectorType() && !isa<VectorType>(SrcType)) { 462 // Cast the scalar to element type 463 QualType EltTy = DstType->getAsExtVectorType()->getElementType(); 464 llvm::Value *Elt = EmitScalarConversion(Src, SrcType, EltTy); 465 466 // Insert the element in element zero of an undef vector 467 llvm::Value *UnV = llvm::UndefValue::get(DstTy); 468 llvm::Value *Idx = llvm::ConstantInt::get(llvm::Type::Int32Ty, 0); 469 UnV = Builder.CreateInsertElement(UnV, Elt, Idx, "tmp"); 470 471 // Splat the element across to all elements 472 llvm::SmallVector<llvm::Constant*, 16> Args; 473 unsigned NumElements = cast<llvm::VectorType>(DstTy)->getNumElements(); 474 for (unsigned i = 0; i < NumElements; i++) 475 Args.push_back(llvm::ConstantInt::get(llvm::Type::Int32Ty, 0)); 476 477 llvm::Constant *Mask = llvm::ConstantVector::get(&Args[0], NumElements); 478 llvm::Value *Yay = Builder.CreateShuffleVector(UnV, UnV, Mask, "splat"); 479 return Yay; 480 } 481 482 // Allow bitcast from vector to integer/fp of the same size. 483 if (isa<llvm::VectorType>(Src->getType()) || 484 isa<llvm::VectorType>(DstTy)) 485 return Builder.CreateBitCast(Src, DstTy, "conv"); 486 487 // Finally, we have the arithmetic types: real int/float. 488 if (isa<llvm::IntegerType>(Src->getType())) { 489 bool InputSigned = SrcType->isSignedIntegerType(); 490 if (isa<llvm::IntegerType>(DstTy)) 491 return Builder.CreateIntCast(Src, DstTy, InputSigned, "conv"); 492 else if (InputSigned) 493 return Builder.CreateSIToFP(Src, DstTy, "conv"); 494 else 495 return Builder.CreateUIToFP(Src, DstTy, "conv"); 496 } 497 498 assert(Src->getType()->isFloatingPoint() && "Unknown real conversion"); 499 if (isa<llvm::IntegerType>(DstTy)) { 500 if (DstType->isSignedIntegerType()) 501 return Builder.CreateFPToSI(Src, DstTy, "conv"); 502 else 503 return Builder.CreateFPToUI(Src, DstTy, "conv"); 504 } 505 506 assert(DstTy->isFloatingPoint() && "Unknown real conversion"); 507 if (DstTy->getTypeID() < Src->getType()->getTypeID()) 508 return Builder.CreateFPTrunc(Src, DstTy, "conv"); 509 else 510 return Builder.CreateFPExt(Src, DstTy, "conv"); 511} 512 513/// EmitComplexToScalarConversion - Emit a conversion from the specified 514/// complex type to the specified destination type, where the destination 515/// type is an LLVM scalar type. 516Value *ScalarExprEmitter:: 517EmitComplexToScalarConversion(CodeGenFunction::ComplexPairTy Src, 518 QualType SrcTy, QualType DstTy) { 519 // Get the source element type. 520 SrcTy = SrcTy->getAsComplexType()->getElementType(); 521 522 // Handle conversions to bool first, they are special: comparisons against 0. 523 if (DstTy->isBooleanType()) { 524 // Complex != 0 -> (Real != 0) | (Imag != 0) 525 Src.first = EmitScalarConversion(Src.first, SrcTy, DstTy); 526 Src.second = EmitScalarConversion(Src.second, SrcTy, DstTy); 527 return Builder.CreateOr(Src.first, Src.second, "tobool"); 528 } 529 530 // C99 6.3.1.7p2: "When a value of complex type is converted to a real type, 531 // the imaginary part of the complex value is discarded and the value of the 532 // real part is converted according to the conversion rules for the 533 // corresponding real type. 534 return EmitScalarConversion(Src.first, SrcTy, DstTy); 535} 536 537 538//===----------------------------------------------------------------------===// 539// Visitor Methods 540//===----------------------------------------------------------------------===// 541 542Value *ScalarExprEmitter::VisitExpr(Expr *E) { 543 CGF.ErrorUnsupported(E, "scalar expression"); 544 if (E->getType()->isVoidType()) 545 return 0; 546 return llvm::UndefValue::get(CGF.ConvertType(E->getType())); 547} 548 549Value *ScalarExprEmitter::VisitShuffleVectorExpr(ShuffleVectorExpr *E) { 550 llvm::SmallVector<llvm::Constant*, 32> indices; 551 for (unsigned i = 2; i < E->getNumSubExprs(); i++) { 552 indices.push_back(cast<llvm::Constant>(CGF.EmitScalarExpr(E->getExpr(i)))); 553 } 554 Value* V1 = CGF.EmitScalarExpr(E->getExpr(0)); 555 Value* V2 = CGF.EmitScalarExpr(E->getExpr(1)); 556 Value* SV = llvm::ConstantVector::get(indices.begin(), indices.size()); 557 return Builder.CreateShuffleVector(V1, V2, SV, "shuffle"); 558} 559 560Value *ScalarExprEmitter::VisitArraySubscriptExpr(ArraySubscriptExpr *E) { 561 TestAndClearIgnoreResultAssign(); 562 563 // Emit subscript expressions in rvalue context's. For most cases, this just 564 // loads the lvalue formed by the subscript expr. However, we have to be 565 // careful, because the base of a vector subscript is occasionally an rvalue, 566 // so we can't get it as an lvalue. 567 if (!E->getBase()->getType()->isVectorType()) 568 return EmitLoadOfLValue(E); 569 570 // Handle the vector case. The base must be a vector, the index must be an 571 // integer value. 572 Value *Base = Visit(E->getBase()); 573 Value *Idx = Visit(E->getIdx()); 574 bool IdxSigned = E->getIdx()->getType()->isSignedIntegerType(); 575 Idx = Builder.CreateIntCast(Idx, llvm::Type::Int32Ty, IdxSigned, 576 "vecidxcast"); 577 return Builder.CreateExtractElement(Base, Idx, "vecext"); 578} 579 580/// VisitImplicitCastExpr - Implicit casts are the same as normal casts, but 581/// also handle things like function to pointer-to-function decay, and array to 582/// pointer decay. 583Value *ScalarExprEmitter::VisitImplicitCastExpr(const ImplicitCastExpr *E) { 584 const Expr *Op = E->getSubExpr(); 585 586 // If this is due to array->pointer conversion, emit the array expression as 587 // an l-value. 588 if (Op->getType()->isArrayType()) { 589 Value *V = EmitLValue(Op).getAddress(); // Bitfields can't be arrays. 590 591 // Note that VLA pointers are always decayed, so we don't need to do 592 // anything here. 593 if (!Op->getType()->isVariableArrayType()) { 594 assert(isa<llvm::PointerType>(V->getType()) && "Expected pointer"); 595 assert(isa<llvm::ArrayType>(cast<llvm::PointerType>(V->getType()) 596 ->getElementType()) && 597 "Expected pointer to array"); 598 V = Builder.CreateStructGEP(V, 0, "arraydecay"); 599 } 600 601 // The resultant pointer type can be implicitly casted to other pointer 602 // types as well (e.g. void*) and can be implicitly converted to integer. 603 const llvm::Type *DestTy = ConvertType(E->getType()); 604 if (V->getType() != DestTy) { 605 if (isa<llvm::PointerType>(DestTy)) 606 V = Builder.CreateBitCast(V, DestTy, "ptrconv"); 607 else { 608 assert(isa<llvm::IntegerType>(DestTy) && "Unknown array decay"); 609 V = Builder.CreatePtrToInt(V, DestTy, "ptrconv"); 610 } 611 } 612 return V; 613 } 614 615 return EmitCastExpr(Op, E->getType()); 616} 617 618 619// VisitCastExpr - Emit code for an explicit or implicit cast. Implicit casts 620// have to handle a more broad range of conversions than explicit casts, as they 621// handle things like function to ptr-to-function decay etc. 622Value *ScalarExprEmitter::EmitCastExpr(const Expr *E, QualType DestTy) { 623 if (!DestTy->isVoidType()) 624 TestAndClearIgnoreResultAssign(); 625 626 // Handle cases where the source is an non-complex type. 627 628 if (!CGF.hasAggregateLLVMType(E->getType())) { 629 Value *Src = Visit(const_cast<Expr*>(E)); 630 631 // Use EmitScalarConversion to perform the conversion. 632 return EmitScalarConversion(Src, E->getType(), DestTy); 633 } 634 635 if (E->getType()->isAnyComplexType()) { 636 // Handle cases where the source is a complex type. 637 bool IgnoreImag = true; 638 bool IgnoreImagAssign = true; 639 bool IgnoreReal = IgnoreResultAssign; 640 bool IgnoreRealAssign = IgnoreResultAssign; 641 if (DestTy->isBooleanType()) 642 IgnoreImagAssign = IgnoreImag = false; 643 else if (DestTy->isVoidType()) { 644 IgnoreReal = IgnoreImag = false; 645 IgnoreRealAssign = IgnoreImagAssign = true; 646 } 647 CodeGenFunction::ComplexPairTy V 648 = CGF.EmitComplexExpr(E, IgnoreReal, IgnoreImag, IgnoreRealAssign, 649 IgnoreImagAssign); 650 return EmitComplexToScalarConversion(V, E->getType(), DestTy); 651 } 652 653 // Okay, this is a cast from an aggregate. It must be a cast to void. Just 654 // evaluate the result and return. 655 CGF.EmitAggExpr(E, 0, false, true); 656 return 0; 657} 658 659Value *ScalarExprEmitter::VisitStmtExpr(const StmtExpr *E) { 660 return CGF.EmitCompoundStmt(*E->getSubStmt(), 661 !E->getType()->isVoidType()).getScalarVal(); 662} 663 664Value *ScalarExprEmitter::VisitBlockDeclRefExpr(const BlockDeclRefExpr *E) { 665 return Builder.CreateLoad(CGF.GetAddrOfBlockDecl(E), false, "tmp"); 666} 667 668//===----------------------------------------------------------------------===// 669// Unary Operators 670//===----------------------------------------------------------------------===// 671 672Value *ScalarExprEmitter::VisitPrePostIncDec(const UnaryOperator *E, 673 bool isInc, bool isPre) { 674 LValue LV = EmitLValue(E->getSubExpr()); 675 QualType ValTy = E->getSubExpr()->getType(); 676 Value *InVal = CGF.EmitLoadOfLValue(LV, ValTy).getScalarVal(); 677 678 int AmountVal = isInc ? 1 : -1; 679 680 if (ValTy->isPointerType() && 681 ValTy->getAsPointerType()->isVariableArrayType()) { 682 // The amount of the addition/subtraction needs to account for the VLA size 683 CGF.ErrorUnsupported(E, "VLA pointer inc/dec"); 684 } 685 686 Value *NextVal; 687 if (const llvm::PointerType *PT = 688 dyn_cast<llvm::PointerType>(InVal->getType())) { 689 llvm::Constant *Inc =llvm::ConstantInt::get(llvm::Type::Int32Ty, AmountVal); 690 if (!isa<llvm::FunctionType>(PT->getElementType())) { 691 NextVal = Builder.CreateGEP(InVal, Inc, "ptrincdec"); 692 } else { 693 const llvm::Type *i8Ty = llvm::PointerType::getUnqual(llvm::Type::Int8Ty); 694 NextVal = Builder.CreateBitCast(InVal, i8Ty, "tmp"); 695 NextVal = Builder.CreateGEP(NextVal, Inc, "ptrincdec"); 696 NextVal = Builder.CreateBitCast(NextVal, InVal->getType()); 697 } 698 } else if (InVal->getType() == llvm::Type::Int1Ty && isInc) { 699 // Bool++ is an interesting case, due to promotion rules, we get: 700 // Bool++ -> Bool = Bool+1 -> Bool = (int)Bool+1 -> 701 // Bool = ((int)Bool+1) != 0 702 // An interesting aspect of this is that increment is always true. 703 // Decrement does not have this property. 704 NextVal = llvm::ConstantInt::getTrue(); 705 } else if (isa<llvm::IntegerType>(InVal->getType())) { 706 NextVal = llvm::ConstantInt::get(InVal->getType(), AmountVal); 707 NextVal = Builder.CreateAdd(InVal, NextVal, isInc ? "inc" : "dec"); 708 } else { 709 // Add the inc/dec to the real part. 710 if (InVal->getType() == llvm::Type::FloatTy) 711 NextVal = 712 llvm::ConstantFP::get(llvm::APFloat(static_cast<float>(AmountVal))); 713 else if (InVal->getType() == llvm::Type::DoubleTy) 714 NextVal = 715 llvm::ConstantFP::get(llvm::APFloat(static_cast<double>(AmountVal))); 716 else { 717 llvm::APFloat F(static_cast<float>(AmountVal)); 718 bool ignored; 719 F.convert(CGF.Target.getLongDoubleFormat(), llvm::APFloat::rmTowardZero, 720 &ignored); 721 NextVal = llvm::ConstantFP::get(F); 722 } 723 NextVal = Builder.CreateFAdd(InVal, NextVal, isInc ? "inc" : "dec"); 724 } 725 726 // Store the updated result through the lvalue. 727 if (LV.isBitfield()) 728 CGF.EmitStoreThroughBitfieldLValue(RValue::get(NextVal), LV, ValTy, 729 &NextVal); 730 else 731 CGF.EmitStoreThroughLValue(RValue::get(NextVal), LV, ValTy); 732 733 // If this is a postinc, return the value read from memory, otherwise use the 734 // updated value. 735 return isPre ? NextVal : InVal; 736} 737 738 739Value *ScalarExprEmitter::VisitUnaryMinus(const UnaryOperator *E) { 740 TestAndClearIgnoreResultAssign(); 741 Value *Op = Visit(E->getSubExpr()); 742 if (Op->getType()->isFPOrFPVector()) 743 return Builder.CreateFNeg(Op, "neg"); 744 return Builder.CreateNeg(Op, "neg"); 745} 746 747Value *ScalarExprEmitter::VisitUnaryNot(const UnaryOperator *E) { 748 TestAndClearIgnoreResultAssign(); 749 Value *Op = Visit(E->getSubExpr()); 750 return Builder.CreateNot(Op, "neg"); 751} 752 753Value *ScalarExprEmitter::VisitUnaryLNot(const UnaryOperator *E) { 754 // Compare operand to zero. 755 Value *BoolVal = CGF.EvaluateExprAsBool(E->getSubExpr()); 756 757 // Invert value. 758 // TODO: Could dynamically modify easy computations here. For example, if 759 // the operand is an icmp ne, turn into icmp eq. 760 BoolVal = Builder.CreateNot(BoolVal, "lnot"); 761 762 // ZExt result to the expr type. 763 return Builder.CreateZExt(BoolVal, ConvertType(E->getType()), "lnot.ext"); 764} 765 766/// VisitSizeOfAlignOfExpr - Return the size or alignment of the type of 767/// argument of the sizeof expression as an integer. 768Value * 769ScalarExprEmitter::VisitSizeOfAlignOfExpr(const SizeOfAlignOfExpr *E) { 770 QualType TypeToSize = E->getTypeOfArgument(); 771 if (E->isSizeOf()) { 772 if (const VariableArrayType *VAT = 773 CGF.getContext().getAsVariableArrayType(TypeToSize)) { 774 if (E->isArgumentType()) { 775 // sizeof(type) - make sure to emit the VLA size. 776 CGF.EmitVLASize(TypeToSize); 777 } else { 778 // C99 6.5.3.4p2: If the argument is an expression of type 779 // VLA, it is evaluated. 780 CGF.EmitAnyExpr(E->getArgumentExpr()); 781 } 782 783 return CGF.GetVLASize(VAT); 784 } 785 } 786 787 // If this isn't sizeof(vla), the result must be constant; use the 788 // constant folding logic so we don't have to duplicate it here. 789 Expr::EvalResult Result; 790 E->Evaluate(Result, CGF.getContext()); 791 return llvm::ConstantInt::get(Result.Val.getInt()); 792} 793 794Value *ScalarExprEmitter::VisitUnaryReal(const UnaryOperator *E) { 795 Expr *Op = E->getSubExpr(); 796 if (Op->getType()->isAnyComplexType()) 797 return CGF.EmitComplexExpr(Op, false, true, false, true).first; 798 return Visit(Op); 799} 800Value *ScalarExprEmitter::VisitUnaryImag(const UnaryOperator *E) { 801 Expr *Op = E->getSubExpr(); 802 if (Op->getType()->isAnyComplexType()) 803 return CGF.EmitComplexExpr(Op, true, false, true, false).second; 804 805 // __imag on a scalar returns zero. Emit the subexpr to ensure side 806 // effects are evaluated, but not the actual value. 807 if (E->isLvalue(CGF.getContext()) == Expr::LV_Valid) 808 CGF.EmitLValue(Op); 809 else 810 CGF.EmitScalarExpr(Op, true); 811 return CGF.getLLVMContext().getNullValue(ConvertType(E->getType())); 812} 813 814Value *ScalarExprEmitter::VisitUnaryOffsetOf(const UnaryOperator *E) 815{ 816 Value* ResultAsPtr = EmitLValue(E->getSubExpr()).getAddress(); 817 const llvm::Type* ResultType = ConvertType(E->getType()); 818 return Builder.CreatePtrToInt(ResultAsPtr, ResultType, "offsetof"); 819} 820 821//===----------------------------------------------------------------------===// 822// Binary Operators 823//===----------------------------------------------------------------------===// 824 825BinOpInfo ScalarExprEmitter::EmitBinOps(const BinaryOperator *E) { 826 TestAndClearIgnoreResultAssign(); 827 BinOpInfo Result; 828 Result.LHS = Visit(E->getLHS()); 829 Result.RHS = Visit(E->getRHS()); 830 Result.Ty = E->getType(); 831 Result.E = E; 832 return Result; 833} 834 835Value *ScalarExprEmitter::EmitCompoundAssign(const CompoundAssignOperator *E, 836 Value *(ScalarExprEmitter::*Func)(const BinOpInfo &)) { 837 bool Ignore = TestAndClearIgnoreResultAssign(); 838 QualType LHSTy = E->getLHS()->getType(), RHSTy = E->getRHS()->getType(); 839 840 BinOpInfo OpInfo; 841 842 if (E->getComputationResultType()->isAnyComplexType()) { 843 // This needs to go through the complex expression emitter, but 844 // it's a tad complicated to do that... I'm leaving it out for now. 845 // (Note that we do actually need the imaginary part of the RHS for 846 // multiplication and division.) 847 CGF.ErrorUnsupported(E, "complex compound assignment"); 848 return llvm::UndefValue::get(CGF.ConvertType(E->getType())); 849 } 850 851 // Emit the RHS first. __block variables need to have the rhs evaluated 852 // first, plus this should improve codegen a little. 853 OpInfo.RHS = Visit(E->getRHS()); 854 OpInfo.Ty = E->getComputationResultType(); 855 OpInfo.E = E; 856 // Load/convert the LHS. 857 LValue LHSLV = EmitLValue(E->getLHS()); 858 OpInfo.LHS = EmitLoadOfLValue(LHSLV, LHSTy); 859 OpInfo.LHS = EmitScalarConversion(OpInfo.LHS, LHSTy, 860 E->getComputationLHSType()); 861 862 // Expand the binary operator. 863 Value *Result = (this->*Func)(OpInfo); 864 865 // Convert the result back to the LHS type. 866 Result = EmitScalarConversion(Result, E->getComputationResultType(), LHSTy); 867 868 // Store the result value into the LHS lvalue. Bit-fields are 869 // handled specially because the result is altered by the store, 870 // i.e., [C99 6.5.16p1] 'An assignment expression has the value of 871 // the left operand after the assignment...'. 872 if (LHSLV.isBitfield()) { 873 if (!LHSLV.isVolatileQualified()) { 874 CGF.EmitStoreThroughBitfieldLValue(RValue::get(Result), LHSLV, LHSTy, 875 &Result); 876 return Result; 877 } else 878 CGF.EmitStoreThroughBitfieldLValue(RValue::get(Result), LHSLV, LHSTy); 879 } else 880 CGF.EmitStoreThroughLValue(RValue::get(Result), LHSLV, LHSTy); 881 if (Ignore) 882 return 0; 883 return EmitLoadOfLValue(LHSLV, E->getType()); 884} 885 886 887Value *ScalarExprEmitter::EmitDiv(const BinOpInfo &Ops) { 888 if (Ops.LHS->getType()->isFPOrFPVector()) 889 return Builder.CreateFDiv(Ops.LHS, Ops.RHS, "div"); 890 else if (Ops.Ty->isUnsignedIntegerType()) 891 return Builder.CreateUDiv(Ops.LHS, Ops.RHS, "div"); 892 else 893 return Builder.CreateSDiv(Ops.LHS, Ops.RHS, "div"); 894} 895 896Value *ScalarExprEmitter::EmitRem(const BinOpInfo &Ops) { 897 // Rem in C can't be a floating point type: C99 6.5.5p2. 898 if (Ops.Ty->isUnsignedIntegerType()) 899 return Builder.CreateURem(Ops.LHS, Ops.RHS, "rem"); 900 else 901 return Builder.CreateSRem(Ops.LHS, Ops.RHS, "rem"); 902} 903 904Value *ScalarExprEmitter::EmitOverflowCheckedBinOp(const BinOpInfo &Ops) { 905 unsigned IID; 906 unsigned OpID = 0; 907 908 switch (Ops.E->getOpcode()) { 909 case BinaryOperator::Add: 910 case BinaryOperator::AddAssign: 911 OpID = 1; 912 IID = llvm::Intrinsic::sadd_with_overflow; 913 break; 914 case BinaryOperator::Sub: 915 case BinaryOperator::SubAssign: 916 OpID = 2; 917 IID = llvm::Intrinsic::ssub_with_overflow; 918 break; 919 case BinaryOperator::Mul: 920 case BinaryOperator::MulAssign: 921 OpID = 3; 922 IID = llvm::Intrinsic::smul_with_overflow; 923 break; 924 default: 925 assert(false && "Unsupported operation for overflow detection"); 926 IID = 0; 927 } 928 OpID <<= 1; 929 OpID |= 1; 930 931 const llvm::Type *opTy = CGF.CGM.getTypes().ConvertType(Ops.Ty); 932 933 llvm::Function *intrinsic = CGF.CGM.getIntrinsic(IID, &opTy, 1); 934 935 Value *resultAndOverflow = Builder.CreateCall2(intrinsic, Ops.LHS, Ops.RHS); 936 Value *result = Builder.CreateExtractValue(resultAndOverflow, 0); 937 Value *overflow = Builder.CreateExtractValue(resultAndOverflow, 1); 938 939 // Branch in case of overflow. 940 llvm::BasicBlock *initialBB = Builder.GetInsertBlock(); 941 llvm::BasicBlock *overflowBB = 942 CGF.createBasicBlock("overflow", CGF.CurFn); 943 llvm::BasicBlock *continueBB = 944 CGF.createBasicBlock("overflow.continue", CGF.CurFn); 945 946 Builder.CreateCondBr(overflow, overflowBB, continueBB); 947 948 // Handle overflow 949 950 Builder.SetInsertPoint(overflowBB); 951 952 // Handler is: 953 // long long *__overflow_handler)(long long a, long long b, char op, 954 // char width) 955 std::vector<const llvm::Type*> handerArgTypes; 956 handerArgTypes.push_back(llvm::Type::Int64Ty); 957 handerArgTypes.push_back(llvm::Type::Int64Ty); 958 handerArgTypes.push_back(llvm::Type::Int8Ty); 959 handerArgTypes.push_back(llvm::Type::Int8Ty); 960 llvm::FunctionType *handlerTy = llvm::FunctionType::get(llvm::Type::Int64Ty, 961 handerArgTypes, false); 962 llvm::Value *handlerFunction = 963 CGF.CGM.getModule().getOrInsertGlobal("__overflow_handler", 964 llvm::PointerType::getUnqual(handlerTy)); 965 handlerFunction = Builder.CreateLoad(handlerFunction); 966 967 llvm::Value *handlerResult = Builder.CreateCall4(handlerFunction, 968 Builder.CreateSExt(Ops.LHS, llvm::Type::Int64Ty), 969 Builder.CreateSExt(Ops.RHS, llvm::Type::Int64Ty), 970 llvm::ConstantInt::get(llvm::Type::Int8Ty, OpID), 971 llvm::ConstantInt::get(llvm::Type::Int8Ty, 972 cast<llvm::IntegerType>(opTy)->getBitWidth())); 973 974 handlerResult = Builder.CreateTrunc(handlerResult, opTy); 975 976 Builder.CreateBr(continueBB); 977 978 // Set up the continuation 979 Builder.SetInsertPoint(continueBB); 980 // Get the correct result 981 llvm::PHINode *phi = Builder.CreatePHI(opTy); 982 phi->reserveOperandSpace(2); 983 phi->addIncoming(result, initialBB); 984 phi->addIncoming(handlerResult, overflowBB); 985 986 return phi; 987} 988 989Value *ScalarExprEmitter::EmitAdd(const BinOpInfo &Ops) { 990 if (!Ops.Ty->isPointerType() && !Ops.Ty->isObjCObjectPointerType()) { 991 if (CGF.getContext().getLangOptions().OverflowChecking && 992 Ops.Ty->isSignedIntegerType()) 993 return EmitOverflowCheckedBinOp(Ops); 994 995 if (Ops.LHS->getType()->isFPOrFPVector()) 996 return Builder.CreateFAdd(Ops.LHS, Ops.RHS, "add"); 997 998 return Builder.CreateAdd(Ops.LHS, Ops.RHS, "add"); 999 } 1000 1001 if (Ops.Ty->isPointerType() && 1002 Ops.Ty->getAsPointerType()->isVariableArrayType()) { 1003 // The amount of the addition needs to account for the VLA size 1004 CGF.ErrorUnsupported(Ops.E, "VLA pointer addition"); 1005 } 1006 Value *Ptr, *Idx; 1007 Expr *IdxExp; 1008 const PointerType *PT = Ops.E->getLHS()->getType()->getAsPointerType(); 1009 const ObjCObjectPointerType *OPT = 1010 Ops.E->getLHS()->getType()->getAsObjCObjectPointerType(); 1011 if (PT || OPT) { 1012 Ptr = Ops.LHS; 1013 Idx = Ops.RHS; 1014 IdxExp = Ops.E->getRHS(); 1015 } else { // int + pointer 1016 PT = Ops.E->getRHS()->getType()->getAsPointerType(); 1017 OPT = Ops.E->getRHS()->getType()->getAsObjCObjectPointerType(); 1018 assert((PT || OPT) && "Invalid add expr"); 1019 Ptr = Ops.RHS; 1020 Idx = Ops.LHS; 1021 IdxExp = Ops.E->getLHS(); 1022 } 1023 1024 unsigned Width = cast<llvm::IntegerType>(Idx->getType())->getBitWidth(); 1025 if (Width < CGF.LLVMPointerWidth) { 1026 // Zero or sign extend the pointer value based on whether the index is 1027 // signed or not. 1028 const llvm::Type *IdxType = llvm::IntegerType::get(CGF.LLVMPointerWidth); 1029 if (IdxExp->getType()->isSignedIntegerType()) 1030 Idx = Builder.CreateSExt(Idx, IdxType, "idx.ext"); 1031 else 1032 Idx = Builder.CreateZExt(Idx, IdxType, "idx.ext"); 1033 } 1034 const QualType ElementType = PT ? PT->getPointeeType() : OPT->getPointeeType(); 1035 // Handle interface types, which are not represented with a concrete 1036 // type. 1037 if (const ObjCInterfaceType *OIT = dyn_cast<ObjCInterfaceType>(ElementType)) { 1038 llvm::Value *InterfaceSize = 1039 llvm::ConstantInt::get(Idx->getType(), 1040 CGF.getContext().getTypeSize(OIT) / 8); 1041 Idx = Builder.CreateMul(Idx, InterfaceSize); 1042 const llvm::Type *i8Ty = llvm::PointerType::getUnqual(llvm::Type::Int8Ty); 1043 Value *Casted = Builder.CreateBitCast(Ptr, i8Ty); 1044 Value *Res = Builder.CreateGEP(Casted, Idx, "add.ptr"); 1045 return Builder.CreateBitCast(Res, Ptr->getType()); 1046 } 1047 1048 // Explicitly handle GNU void* and function pointer arithmetic 1049 // extensions. The GNU void* casts amount to no-ops since our void* 1050 // type is i8*, but this is future proof. 1051 if (ElementType->isVoidType() || ElementType->isFunctionType()) { 1052 const llvm::Type *i8Ty = llvm::PointerType::getUnqual(llvm::Type::Int8Ty); 1053 Value *Casted = Builder.CreateBitCast(Ptr, i8Ty); 1054 Value *Res = Builder.CreateGEP(Casted, Idx, "add.ptr"); 1055 return Builder.CreateBitCast(Res, Ptr->getType()); 1056 } 1057 1058 return Builder.CreateGEP(Ptr, Idx, "add.ptr"); 1059} 1060 1061Value *ScalarExprEmitter::EmitSub(const BinOpInfo &Ops) { 1062 if (!isa<llvm::PointerType>(Ops.LHS->getType())) { 1063 if (CGF.getContext().getLangOptions().OverflowChecking 1064 && Ops.Ty->isSignedIntegerType()) 1065 return EmitOverflowCheckedBinOp(Ops); 1066 1067 if (Ops.LHS->getType()->isFPOrFPVector()) 1068 return Builder.CreateFSub(Ops.LHS, Ops.RHS, "sub"); 1069 return Builder.CreateSub(Ops.LHS, Ops.RHS, "sub"); 1070 } 1071 1072 if (Ops.E->getLHS()->getType()->isPointerType() && 1073 Ops.E->getLHS()->getType()->getAsPointerType()->isVariableArrayType()) { 1074 // The amount of the addition needs to account for the VLA size for 1075 // ptr-int 1076 // The amount of the division needs to account for the VLA size for 1077 // ptr-ptr. 1078 CGF.ErrorUnsupported(Ops.E, "VLA pointer subtraction"); 1079 } 1080 1081 const QualType LHSType = Ops.E->getLHS()->getType(); 1082 const QualType LHSElementType = LHSType->getPointeeType(); 1083 if (!isa<llvm::PointerType>(Ops.RHS->getType())) { 1084 // pointer - int 1085 Value *Idx = Ops.RHS; 1086 unsigned Width = cast<llvm::IntegerType>(Idx->getType())->getBitWidth(); 1087 if (Width < CGF.LLVMPointerWidth) { 1088 // Zero or sign extend the pointer value based on whether the index is 1089 // signed or not. 1090 const llvm::Type *IdxType = llvm::IntegerType::get(CGF.LLVMPointerWidth); 1091 if (Ops.E->getRHS()->getType()->isSignedIntegerType()) 1092 Idx = Builder.CreateSExt(Idx, IdxType, "idx.ext"); 1093 else 1094 Idx = Builder.CreateZExt(Idx, IdxType, "idx.ext"); 1095 } 1096 Idx = Builder.CreateNeg(Idx, "sub.ptr.neg"); 1097 1098 // Handle interface types, which are not represented with a concrete 1099 // type. 1100 if (const ObjCInterfaceType *OIT = 1101 dyn_cast<ObjCInterfaceType>(LHSElementType)) { 1102 llvm::Value *InterfaceSize = 1103 llvm::ConstantInt::get(Idx->getType(), 1104 CGF.getContext().getTypeSize(OIT) / 8); 1105 Idx = Builder.CreateMul(Idx, InterfaceSize); 1106 const llvm::Type *i8Ty = llvm::PointerType::getUnqual(llvm::Type::Int8Ty); 1107 Value *LHSCasted = Builder.CreateBitCast(Ops.LHS, i8Ty); 1108 Value *Res = Builder.CreateGEP(LHSCasted, Idx, "add.ptr"); 1109 return Builder.CreateBitCast(Res, Ops.LHS->getType()); 1110 } 1111 1112 // Explicitly handle GNU void* and function pointer arithmetic 1113 // extensions. The GNU void* casts amount to no-ops since our 1114 // void* type is i8*, but this is future proof. 1115 if (LHSElementType->isVoidType() || LHSElementType->isFunctionType()) { 1116 const llvm::Type *i8Ty = llvm::PointerType::getUnqual(llvm::Type::Int8Ty); 1117 Value *LHSCasted = Builder.CreateBitCast(Ops.LHS, i8Ty); 1118 Value *Res = Builder.CreateGEP(LHSCasted, Idx, "sub.ptr"); 1119 return Builder.CreateBitCast(Res, Ops.LHS->getType()); 1120 } 1121 1122 return Builder.CreateGEP(Ops.LHS, Idx, "sub.ptr"); 1123 } else { 1124 // pointer - pointer 1125 Value *LHS = Ops.LHS; 1126 Value *RHS = Ops.RHS; 1127 1128 uint64_t ElementSize; 1129 1130 // Handle GCC extension for pointer arithmetic on void* and function pointer 1131 // types. 1132 if (LHSElementType->isVoidType() || LHSElementType->isFunctionType()) { 1133 ElementSize = 1; 1134 } else { 1135 ElementSize = CGF.getContext().getTypeSize(LHSElementType) / 8; 1136 } 1137 1138 const llvm::Type *ResultType = ConvertType(Ops.Ty); 1139 LHS = Builder.CreatePtrToInt(LHS, ResultType, "sub.ptr.lhs.cast"); 1140 RHS = Builder.CreatePtrToInt(RHS, ResultType, "sub.ptr.rhs.cast"); 1141 Value *BytesBetween = Builder.CreateSub(LHS, RHS, "sub.ptr.sub"); 1142 1143 // Optimize out the shift for element size of 1. 1144 if (ElementSize == 1) 1145 return BytesBetween; 1146 1147 // HACK: LLVM doesn't have an divide instruction that 'knows' there is no 1148 // remainder. As such, we handle common power-of-two cases here to generate 1149 // better code. See PR2247. 1150 if (llvm::isPowerOf2_64(ElementSize)) { 1151 Value *ShAmt = 1152 llvm::ConstantInt::get(ResultType, llvm::Log2_64(ElementSize)); 1153 return Builder.CreateAShr(BytesBetween, ShAmt, "sub.ptr.shr"); 1154 } 1155 1156 // Otherwise, do a full sdiv. 1157 Value *BytesPerElt = llvm::ConstantInt::get(ResultType, ElementSize); 1158 return Builder.CreateSDiv(BytesBetween, BytesPerElt, "sub.ptr.div"); 1159 } 1160} 1161 1162Value *ScalarExprEmitter::EmitShl(const BinOpInfo &Ops) { 1163 // LLVM requires the LHS and RHS to be the same type: promote or truncate the 1164 // RHS to the same size as the LHS. 1165 Value *RHS = Ops.RHS; 1166 if (Ops.LHS->getType() != RHS->getType()) 1167 RHS = Builder.CreateIntCast(RHS, Ops.LHS->getType(), false, "sh_prom"); 1168 1169 return Builder.CreateShl(Ops.LHS, RHS, "shl"); 1170} 1171 1172Value *ScalarExprEmitter::EmitShr(const BinOpInfo &Ops) { 1173 // LLVM requires the LHS and RHS to be the same type: promote or truncate the 1174 // RHS to the same size as the LHS. 1175 Value *RHS = Ops.RHS; 1176 if (Ops.LHS->getType() != RHS->getType()) 1177 RHS = Builder.CreateIntCast(RHS, Ops.LHS->getType(), false, "sh_prom"); 1178 1179 if (Ops.Ty->isUnsignedIntegerType()) 1180 return Builder.CreateLShr(Ops.LHS, RHS, "shr"); 1181 return Builder.CreateAShr(Ops.LHS, RHS, "shr"); 1182} 1183 1184Value *ScalarExprEmitter::EmitCompare(const BinaryOperator *E,unsigned UICmpOpc, 1185 unsigned SICmpOpc, unsigned FCmpOpc) { 1186 TestAndClearIgnoreResultAssign(); 1187 Value *Result; 1188 QualType LHSTy = E->getLHS()->getType(); 1189 if (!LHSTy->isAnyComplexType()) { 1190 Value *LHS = Visit(E->getLHS()); 1191 Value *RHS = Visit(E->getRHS()); 1192 1193 if (LHS->getType()->isFloatingPoint()) { 1194 Result = Builder.CreateFCmp((llvm::CmpInst::Predicate)FCmpOpc, 1195 LHS, RHS, "cmp"); 1196 } else if (LHSTy->isSignedIntegerType()) { 1197 Result = Builder.CreateICmp((llvm::ICmpInst::Predicate)SICmpOpc, 1198 LHS, RHS, "cmp"); 1199 } else { 1200 // Unsigned integers and pointers. 1201 Result = Builder.CreateICmp((llvm::ICmpInst::Predicate)UICmpOpc, 1202 LHS, RHS, "cmp"); 1203 } 1204 1205 // If this is a vector comparison, sign extend the result to the appropriate 1206 // vector integer type and return it (don't convert to bool). 1207 if (LHSTy->isVectorType()) 1208 return Builder.CreateSExt(Result, ConvertType(E->getType()), "sext"); 1209 1210 } else { 1211 // Complex Comparison: can only be an equality comparison. 1212 CodeGenFunction::ComplexPairTy LHS = CGF.EmitComplexExpr(E->getLHS()); 1213 CodeGenFunction::ComplexPairTy RHS = CGF.EmitComplexExpr(E->getRHS()); 1214 1215 QualType CETy = LHSTy->getAsComplexType()->getElementType(); 1216 1217 Value *ResultR, *ResultI; 1218 if (CETy->isRealFloatingType()) { 1219 ResultR = Builder.CreateFCmp((llvm::FCmpInst::Predicate)FCmpOpc, 1220 LHS.first, RHS.first, "cmp.r"); 1221 ResultI = Builder.CreateFCmp((llvm::FCmpInst::Predicate)FCmpOpc, 1222 LHS.second, RHS.second, "cmp.i"); 1223 } else { 1224 // Complex comparisons can only be equality comparisons. As such, signed 1225 // and unsigned opcodes are the same. 1226 ResultR = Builder.CreateICmp((llvm::ICmpInst::Predicate)UICmpOpc, 1227 LHS.first, RHS.first, "cmp.r"); 1228 ResultI = Builder.CreateICmp((llvm::ICmpInst::Predicate)UICmpOpc, 1229 LHS.second, RHS.second, "cmp.i"); 1230 } 1231 1232 if (E->getOpcode() == BinaryOperator::EQ) { 1233 Result = Builder.CreateAnd(ResultR, ResultI, "and.ri"); 1234 } else { 1235 assert(E->getOpcode() == BinaryOperator::NE && 1236 "Complex comparison other than == or != ?"); 1237 Result = Builder.CreateOr(ResultR, ResultI, "or.ri"); 1238 } 1239 } 1240 1241 return EmitScalarConversion(Result, CGF.getContext().BoolTy, E->getType()); 1242} 1243 1244Value *ScalarExprEmitter::VisitBinAssign(const BinaryOperator *E) { 1245 bool Ignore = TestAndClearIgnoreResultAssign(); 1246 1247 // __block variables need to have the rhs evaluated first, plus this should 1248 // improve codegen just a little. 1249 Value *RHS = Visit(E->getRHS()); 1250 LValue LHS = EmitLValue(E->getLHS()); 1251 1252 // Store the value into the LHS. Bit-fields are handled specially 1253 // because the result is altered by the store, i.e., [C99 6.5.16p1] 1254 // 'An assignment expression has the value of the left operand after 1255 // the assignment...'. 1256 if (LHS.isBitfield()) { 1257 if (!LHS.isVolatileQualified()) { 1258 CGF.EmitStoreThroughBitfieldLValue(RValue::get(RHS), LHS, E->getType(), 1259 &RHS); 1260 return RHS; 1261 } else 1262 CGF.EmitStoreThroughBitfieldLValue(RValue::get(RHS), LHS, E->getType()); 1263 } else 1264 CGF.EmitStoreThroughLValue(RValue::get(RHS), LHS, E->getType()); 1265 if (Ignore) 1266 return 0; 1267 return EmitLoadOfLValue(LHS, E->getType()); 1268} 1269 1270Value *ScalarExprEmitter::VisitBinLAnd(const BinaryOperator *E) { 1271 // If we have 0 && RHS, see if we can elide RHS, if so, just return 0. 1272 // If we have 1 && X, just emit X without inserting the control flow. 1273 if (int Cond = CGF.ConstantFoldsToSimpleInteger(E->getLHS())) { 1274 if (Cond == 1) { // If we have 1 && X, just emit X. 1275 Value *RHSCond = CGF.EvaluateExprAsBool(E->getRHS()); 1276 // ZExt result to int. 1277 return Builder.CreateZExt(RHSCond, CGF.LLVMIntTy, "land.ext"); 1278 } 1279 1280 // 0 && RHS: If it is safe, just elide the RHS, and return 0. 1281 if (!CGF.ContainsLabel(E->getRHS())) 1282 return CGF.getLLVMContext().getNullValue(CGF.LLVMIntTy); 1283 } 1284 1285 llvm::BasicBlock *ContBlock = CGF.createBasicBlock("land.end"); 1286 llvm::BasicBlock *RHSBlock = CGF.createBasicBlock("land.rhs"); 1287 1288 // Branch on the LHS first. If it is false, go to the failure (cont) block. 1289 CGF.EmitBranchOnBoolExpr(E->getLHS(), RHSBlock, ContBlock); 1290 1291 // Any edges into the ContBlock are now from an (indeterminate number of) 1292 // edges from this first condition. All of these values will be false. Start 1293 // setting up the PHI node in the Cont Block for this. 1294 llvm::PHINode *PN = llvm::PHINode::Create(llvm::Type::Int1Ty, "", ContBlock); 1295 PN->reserveOperandSpace(2); // Normal case, two inputs. 1296 for (llvm::pred_iterator PI = pred_begin(ContBlock), PE = pred_end(ContBlock); 1297 PI != PE; ++PI) 1298 PN->addIncoming(llvm::ConstantInt::getFalse(), *PI); 1299 1300 CGF.PushConditionalTempDestruction(); 1301 CGF.EmitBlock(RHSBlock); 1302 Value *RHSCond = CGF.EvaluateExprAsBool(E->getRHS()); 1303 CGF.PopConditionalTempDestruction(); 1304 1305 // Reaquire the RHS block, as there may be subblocks inserted. 1306 RHSBlock = Builder.GetInsertBlock(); 1307 1308 // Emit an unconditional branch from this block to ContBlock. Insert an entry 1309 // into the phi node for the edge with the value of RHSCond. 1310 CGF.EmitBlock(ContBlock); 1311 PN->addIncoming(RHSCond, RHSBlock); 1312 1313 // ZExt result to int. 1314 return Builder.CreateZExt(PN, CGF.LLVMIntTy, "land.ext"); 1315} 1316 1317Value *ScalarExprEmitter::VisitBinLOr(const BinaryOperator *E) { 1318 // If we have 1 || RHS, see if we can elide RHS, if so, just return 1. 1319 // If we have 0 || X, just emit X without inserting the control flow. 1320 if (int Cond = CGF.ConstantFoldsToSimpleInteger(E->getLHS())) { 1321 if (Cond == -1) { // If we have 0 || X, just emit X. 1322 Value *RHSCond = CGF.EvaluateExprAsBool(E->getRHS()); 1323 // ZExt result to int. 1324 return Builder.CreateZExt(RHSCond, CGF.LLVMIntTy, "lor.ext"); 1325 } 1326 1327 // 1 || RHS: If it is safe, just elide the RHS, and return 1. 1328 if (!CGF.ContainsLabel(E->getRHS())) 1329 return llvm::ConstantInt::get(CGF.LLVMIntTy, 1); 1330 } 1331 1332 llvm::BasicBlock *ContBlock = CGF.createBasicBlock("lor.end"); 1333 llvm::BasicBlock *RHSBlock = CGF.createBasicBlock("lor.rhs"); 1334 1335 // Branch on the LHS first. If it is true, go to the success (cont) block. 1336 CGF.EmitBranchOnBoolExpr(E->getLHS(), ContBlock, RHSBlock); 1337 1338 // Any edges into the ContBlock are now from an (indeterminate number of) 1339 // edges from this first condition. All of these values will be true. Start 1340 // setting up the PHI node in the Cont Block for this. 1341 llvm::PHINode *PN = llvm::PHINode::Create(llvm::Type::Int1Ty, "", ContBlock); 1342 PN->reserveOperandSpace(2); // Normal case, two inputs. 1343 for (llvm::pred_iterator PI = pred_begin(ContBlock), PE = pred_end(ContBlock); 1344 PI != PE; ++PI) 1345 PN->addIncoming(llvm::ConstantInt::getTrue(), *PI); 1346 1347 CGF.PushConditionalTempDestruction(); 1348 1349 // Emit the RHS condition as a bool value. 1350 CGF.EmitBlock(RHSBlock); 1351 Value *RHSCond = CGF.EvaluateExprAsBool(E->getRHS()); 1352 1353 CGF.PopConditionalTempDestruction(); 1354 1355 // Reaquire the RHS block, as there may be subblocks inserted. 1356 RHSBlock = Builder.GetInsertBlock(); 1357 1358 // Emit an unconditional branch from this block to ContBlock. Insert an entry 1359 // into the phi node for the edge with the value of RHSCond. 1360 CGF.EmitBlock(ContBlock); 1361 PN->addIncoming(RHSCond, RHSBlock); 1362 1363 // ZExt result to int. 1364 return Builder.CreateZExt(PN, CGF.LLVMIntTy, "lor.ext"); 1365} 1366 1367Value *ScalarExprEmitter::VisitBinComma(const BinaryOperator *E) { 1368 CGF.EmitStmt(E->getLHS()); 1369 CGF.EnsureInsertPoint(); 1370 return Visit(E->getRHS()); 1371} 1372 1373//===----------------------------------------------------------------------===// 1374// Other Operators 1375//===----------------------------------------------------------------------===// 1376 1377/// isCheapEnoughToEvaluateUnconditionally - Return true if the specified 1378/// expression is cheap enough and side-effect-free enough to evaluate 1379/// unconditionally instead of conditionally. This is used to convert control 1380/// flow into selects in some cases. 1381static bool isCheapEnoughToEvaluateUnconditionally(const Expr *E) { 1382 if (const ParenExpr *PE = dyn_cast<ParenExpr>(E)) 1383 return isCheapEnoughToEvaluateUnconditionally(PE->getSubExpr()); 1384 1385 // TODO: Allow anything we can constant fold to an integer or fp constant. 1386 if (isa<IntegerLiteral>(E) || isa<CharacterLiteral>(E) || 1387 isa<FloatingLiteral>(E)) 1388 return true; 1389 1390 // Non-volatile automatic variables too, to get "cond ? X : Y" where 1391 // X and Y are local variables. 1392 if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(E)) 1393 if (const VarDecl *VD = dyn_cast<VarDecl>(DRE->getDecl())) 1394 if (VD->hasLocalStorage() && !VD->getType().isVolatileQualified()) 1395 return true; 1396 1397 return false; 1398} 1399 1400 1401Value *ScalarExprEmitter:: 1402VisitConditionalOperator(const ConditionalOperator *E) { 1403 TestAndClearIgnoreResultAssign(); 1404 // If the condition constant folds and can be elided, try to avoid emitting 1405 // the condition and the dead arm. 1406 if (int Cond = CGF.ConstantFoldsToSimpleInteger(E->getCond())){ 1407 Expr *Live = E->getLHS(), *Dead = E->getRHS(); 1408 if (Cond == -1) 1409 std::swap(Live, Dead); 1410 1411 // If the dead side doesn't have labels we need, and if the Live side isn't 1412 // the gnu missing ?: extension (which we could handle, but don't bother 1413 // to), just emit the Live part. 1414 if ((!Dead || !CGF.ContainsLabel(Dead)) && // No labels in dead part 1415 Live) // Live part isn't missing. 1416 return Visit(Live); 1417 } 1418 1419 1420 // If this is a really simple expression (like x ? 4 : 5), emit this as a 1421 // select instead of as control flow. We can only do this if it is cheap and 1422 // safe to evaluate the LHS and RHS unconditionally. 1423 if (E->getLHS() && isCheapEnoughToEvaluateUnconditionally(E->getLHS()) && 1424 isCheapEnoughToEvaluateUnconditionally(E->getRHS())) { 1425 llvm::Value *CondV = CGF.EvaluateExprAsBool(E->getCond()); 1426 llvm::Value *LHS = Visit(E->getLHS()); 1427 llvm::Value *RHS = Visit(E->getRHS()); 1428 return Builder.CreateSelect(CondV, LHS, RHS, "cond"); 1429 } 1430 1431 1432 llvm::BasicBlock *LHSBlock = CGF.createBasicBlock("cond.true"); 1433 llvm::BasicBlock *RHSBlock = CGF.createBasicBlock("cond.false"); 1434 llvm::BasicBlock *ContBlock = CGF.createBasicBlock("cond.end"); 1435 Value *CondVal = 0; 1436 1437 // If we don't have the GNU missing condition extension, emit a branch on 1438 // bool the normal way. 1439 if (E->getLHS()) { 1440 // Otherwise, just use EmitBranchOnBoolExpr to get small and simple code for 1441 // the branch on bool. 1442 CGF.EmitBranchOnBoolExpr(E->getCond(), LHSBlock, RHSBlock); 1443 } else { 1444 // Otherwise, for the ?: extension, evaluate the conditional and then 1445 // convert it to bool the hard way. We do this explicitly because we need 1446 // the unconverted value for the missing middle value of the ?:. 1447 CondVal = CGF.EmitScalarExpr(E->getCond()); 1448 1449 // In some cases, EmitScalarConversion will delete the "CondVal" expression 1450 // if there are no extra uses (an optimization). Inhibit this by making an 1451 // extra dead use, because we're going to add a use of CondVal later. We 1452 // don't use the builder for this, because we don't want it to get optimized 1453 // away. This leaves dead code, but the ?: extension isn't common. 1454 new llvm::BitCastInst(CondVal, CondVal->getType(), "dummy?:holder", 1455 Builder.GetInsertBlock()); 1456 1457 Value *CondBoolVal = 1458 CGF.EmitScalarConversion(CondVal, E->getCond()->getType(), 1459 CGF.getContext().BoolTy); 1460 Builder.CreateCondBr(CondBoolVal, LHSBlock, RHSBlock); 1461 } 1462 1463 CGF.PushConditionalTempDestruction(); 1464 CGF.EmitBlock(LHSBlock); 1465 1466 // Handle the GNU extension for missing LHS. 1467 Value *LHS; 1468 if (E->getLHS()) 1469 LHS = Visit(E->getLHS()); 1470 else // Perform promotions, to handle cases like "short ?: int" 1471 LHS = EmitScalarConversion(CondVal, E->getCond()->getType(), E->getType()); 1472 1473 CGF.PopConditionalTempDestruction(); 1474 LHSBlock = Builder.GetInsertBlock(); 1475 CGF.EmitBranch(ContBlock); 1476 1477 CGF.PushConditionalTempDestruction(); 1478 CGF.EmitBlock(RHSBlock); 1479 1480 Value *RHS = Visit(E->getRHS()); 1481 CGF.PopConditionalTempDestruction(); 1482 RHSBlock = Builder.GetInsertBlock(); 1483 CGF.EmitBranch(ContBlock); 1484 1485 CGF.EmitBlock(ContBlock); 1486 1487 if (!LHS || !RHS) { 1488 assert(E->getType()->isVoidType() && "Non-void value should have a value"); 1489 return 0; 1490 } 1491 1492 // Create a PHI node for the real part. 1493 llvm::PHINode *PN = Builder.CreatePHI(LHS->getType(), "cond"); 1494 PN->reserveOperandSpace(2); 1495 PN->addIncoming(LHS, LHSBlock); 1496 PN->addIncoming(RHS, RHSBlock); 1497 return PN; 1498} 1499 1500Value *ScalarExprEmitter::VisitChooseExpr(ChooseExpr *E) { 1501 return Visit(E->getChosenSubExpr(CGF.getContext())); 1502} 1503 1504Value *ScalarExprEmitter::VisitVAArgExpr(VAArgExpr *VE) { 1505 llvm::Value *ArgValue = CGF.EmitVAListRef(VE->getSubExpr()); 1506 llvm::Value *ArgPtr = CGF.EmitVAArg(ArgValue, VE->getType()); 1507 1508 // If EmitVAArg fails, we fall back to the LLVM instruction. 1509 if (!ArgPtr) 1510 return Builder.CreateVAArg(ArgValue, ConvertType(VE->getType())); 1511 1512 // FIXME Volatility. 1513 return Builder.CreateLoad(ArgPtr); 1514} 1515 1516Value *ScalarExprEmitter::VisitBlockExpr(const BlockExpr *BE) { 1517 return CGF.BuildBlockLiteralTmp(BE); 1518} 1519 1520//===----------------------------------------------------------------------===// 1521// Entry Point into this File 1522//===----------------------------------------------------------------------===// 1523 1524/// EmitScalarExpr - Emit the computation of the specified expression of 1525/// scalar type, ignoring the result. 1526Value *CodeGenFunction::EmitScalarExpr(const Expr *E, bool IgnoreResultAssign) { 1527 assert(E && !hasAggregateLLVMType(E->getType()) && 1528 "Invalid scalar expression to emit"); 1529 1530 return ScalarExprEmitter(*this, IgnoreResultAssign) 1531 .Visit(const_cast<Expr*>(E)); 1532} 1533 1534/// EmitScalarConversion - Emit a conversion from the specified type to the 1535/// specified destination type, both of which are LLVM scalar types. 1536Value *CodeGenFunction::EmitScalarConversion(Value *Src, QualType SrcTy, 1537 QualType DstTy) { 1538 assert(!hasAggregateLLVMType(SrcTy) && !hasAggregateLLVMType(DstTy) && 1539 "Invalid scalar expression to emit"); 1540 return ScalarExprEmitter(*this).EmitScalarConversion(Src, SrcTy, DstTy); 1541} 1542 1543/// EmitComplexToScalarConversion - Emit a conversion from the specified 1544/// complex type to the specified destination type, where the destination 1545/// type is an LLVM scalar type. 1546Value *CodeGenFunction::EmitComplexToScalarConversion(ComplexPairTy Src, 1547 QualType SrcTy, 1548 QualType DstTy) { 1549 assert(SrcTy->isAnyComplexType() && !hasAggregateLLVMType(DstTy) && 1550 "Invalid complex -> scalar conversion"); 1551 return ScalarExprEmitter(*this).EmitComplexToScalarConversion(Src, SrcTy, 1552 DstTy); 1553} 1554 1555Value *CodeGenFunction::EmitShuffleVector(Value* V1, Value *V2, ...) { 1556 assert(V1->getType() == V2->getType() && 1557 "Vector operands must be of the same type"); 1558 unsigned NumElements = 1559 cast<llvm::VectorType>(V1->getType())->getNumElements(); 1560 1561 va_list va; 1562 va_start(va, V2); 1563 1564 llvm::SmallVector<llvm::Constant*, 16> Args; 1565 for (unsigned i = 0; i < NumElements; i++) { 1566 int n = va_arg(va, int); 1567 assert(n >= 0 && n < (int)NumElements * 2 && 1568 "Vector shuffle index out of bounds!"); 1569 Args.push_back(llvm::ConstantInt::get(llvm::Type::Int32Ty, n)); 1570 } 1571 1572 const char *Name = va_arg(va, const char *); 1573 va_end(va); 1574 1575 llvm::Constant *Mask = llvm::ConstantVector::get(&Args[0], NumElements); 1576 1577 return Builder.CreateShuffleVector(V1, V2, Mask, Name); 1578} 1579 1580llvm::Value *CodeGenFunction::EmitVector(llvm::Value * const *Vals, 1581 unsigned NumVals, bool isSplat) { 1582 llvm::Value *Vec 1583 = llvm::UndefValue::get(llvm::VectorType::get(Vals[0]->getType(), NumVals)); 1584 1585 for (unsigned i = 0, e = NumVals; i != e; ++i) { 1586 llvm::Value *Val = isSplat ? Vals[0] : Vals[i]; 1587 llvm::Value *Idx = llvm::ConstantInt::get(llvm::Type::Int32Ty, i); 1588 Vec = Builder.CreateInsertElement(Vec, Val, Idx, "tmp"); 1589 } 1590 1591 return Vec; 1592} 1593