CGExprScalar.cpp revision 58f9f2c884af6b72d036b746a016d8031d31cb7a
1//===--- CGExprScalar.cpp - Emit LLVM Code for Scalar Exprs ---------------===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9// 10// This contains code to emit Expr nodes with scalar LLVM types as LLVM code. 11// 12//===----------------------------------------------------------------------===// 13 14#include "CodeGenFunction.h" 15#include "CodeGenModule.h" 16#include "clang/AST/ASTContext.h" 17#include "clang/AST/DeclObjC.h" 18#include "clang/AST/StmtVisitor.h" 19#include "clang/Basic/TargetInfo.h" 20#include "llvm/Constants.h" 21#include "llvm/Function.h" 22#include "llvm/GlobalVariable.h" 23#include "llvm/Intrinsics.h" 24#include "llvm/Module.h" 25#include "llvm/Support/Compiler.h" 26#include "llvm/Support/CFG.h" 27#include "llvm/Target/TargetData.h" 28#include <cstdarg> 29 30using namespace clang; 31using namespace CodeGen; 32using llvm::Value; 33 34//===----------------------------------------------------------------------===// 35// Scalar Expression Emitter 36//===----------------------------------------------------------------------===// 37 38struct BinOpInfo { 39 Value *LHS; 40 Value *RHS; 41 QualType Ty; // Computation Type. 42 const BinaryOperator *E; 43}; 44 45namespace { 46class VISIBILITY_HIDDEN ScalarExprEmitter 47 : public StmtVisitor<ScalarExprEmitter, Value*> { 48 CodeGenFunction &CGF; 49 CGBuilderTy &Builder; 50 bool IgnoreResultAssign; 51public: 52 53 ScalarExprEmitter(CodeGenFunction &cgf, bool ira=false) 54 : CGF(cgf), Builder(CGF.Builder), IgnoreResultAssign(ira) { 55 } 56 57 //===--------------------------------------------------------------------===// 58 // Utilities 59 //===--------------------------------------------------------------------===// 60 61 bool TestAndClearIgnoreResultAssign() { 62 bool I = IgnoreResultAssign; 63 IgnoreResultAssign = false; 64 return I; 65 } 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 CGF.getLLVMContext().getNullValue(ConvertType(E->getType())); 122 } 123 Value *VisitGNUNullExpr(const GNUNullExpr *E) { 124 return CGF.getLLVMContext().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 = CGF.getLLVMContext().getNullValue(ElementType); 214 V = Builder.CreateInsertElement(V, NewV, Idx); 215 } 216 217 return V; 218 } 219 220 Value *VisitImplicitValueInitExpr(const ImplicitValueInitExpr *E) { 221 return CGF.getLLVMContext().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 if (Ops.LHS->getType()->isFPOrFPVector()) 298 return Builder.CreateFMul(Ops.LHS, Ops.RHS, "mul"); 299 return Builder.CreateMul(Ops.LHS, Ops.RHS, "mul"); 300 } 301 /// Create a binary op that checks for overflow. 302 /// Currently only supports +, - and *. 303 Value *EmitOverflowCheckedBinOp(const BinOpInfo &Ops); 304 Value *EmitDiv(const BinOpInfo &Ops); 305 Value *EmitRem(const BinOpInfo &Ops); 306 Value *EmitAdd(const BinOpInfo &Ops); 307 Value *EmitSub(const BinOpInfo &Ops); 308 Value *EmitShl(const BinOpInfo &Ops); 309 Value *EmitShr(const BinOpInfo &Ops); 310 Value *EmitAnd(const BinOpInfo &Ops) { 311 return Builder.CreateAnd(Ops.LHS, Ops.RHS, "and"); 312 } 313 Value *EmitXor(const BinOpInfo &Ops) { 314 return Builder.CreateXor(Ops.LHS, Ops.RHS, "xor"); 315 } 316 Value *EmitOr (const BinOpInfo &Ops) { 317 return Builder.CreateOr(Ops.LHS, Ops.RHS, "or"); 318 } 319 320 BinOpInfo EmitBinOps(const BinaryOperator *E); 321 Value *EmitCompoundAssign(const CompoundAssignOperator *E, 322 Value *(ScalarExprEmitter::*F)(const BinOpInfo &)); 323 324 // Binary operators and binary compound assignment operators. 325#define HANDLEBINOP(OP) \ 326 Value *VisitBin ## OP(const BinaryOperator *E) { \ 327 return Emit ## OP(EmitBinOps(E)); \ 328 } \ 329 Value *VisitBin ## OP ## Assign(const CompoundAssignOperator *E) { \ 330 return EmitCompoundAssign(E, &ScalarExprEmitter::Emit ## OP); \ 331 } 332 HANDLEBINOP(Mul); 333 HANDLEBINOP(Div); 334 HANDLEBINOP(Rem); 335 HANDLEBINOP(Add); 336 HANDLEBINOP(Sub); 337 HANDLEBINOP(Shl); 338 HANDLEBINOP(Shr); 339 HANDLEBINOP(And); 340 HANDLEBINOP(Xor); 341 HANDLEBINOP(Or); 342#undef HANDLEBINOP 343 344 // Comparisons. 345 Value *EmitCompare(const BinaryOperator *E, unsigned UICmpOpc, 346 unsigned SICmpOpc, unsigned FCmpOpc); 347#define VISITCOMP(CODE, UI, SI, FP) \ 348 Value *VisitBin##CODE(const BinaryOperator *E) { \ 349 return EmitCompare(E, llvm::ICmpInst::UI, llvm::ICmpInst::SI, \ 350 llvm::FCmpInst::FP); } 351 VISITCOMP(LT, ICMP_ULT, ICMP_SLT, FCMP_OLT); 352 VISITCOMP(GT, ICMP_UGT, ICMP_SGT, FCMP_OGT); 353 VISITCOMP(LE, ICMP_ULE, ICMP_SLE, FCMP_OLE); 354 VISITCOMP(GE, ICMP_UGE, ICMP_SGE, FCMP_OGE); 355 VISITCOMP(EQ, ICMP_EQ , ICMP_EQ , FCMP_OEQ); 356 VISITCOMP(NE, ICMP_NE , ICMP_NE , FCMP_UNE); 357#undef VISITCOMP 358 359 Value *VisitBinAssign (const BinaryOperator *E); 360 361 Value *VisitBinLAnd (const BinaryOperator *E); 362 Value *VisitBinLOr (const BinaryOperator *E); 363 Value *VisitBinComma (const BinaryOperator *E); 364 365 // Other Operators. 366 Value *VisitBlockExpr(const BlockExpr *BE); 367 Value *VisitConditionalOperator(const ConditionalOperator *CO); 368 Value *VisitChooseExpr(ChooseExpr *CE); 369 Value *VisitVAArgExpr(VAArgExpr *VE); 370 Value *VisitObjCStringLiteral(const ObjCStringLiteral *E) { 371 return CGF.EmitObjCStringLiteral(E); 372 } 373}; 374} // end anonymous namespace. 375 376//===----------------------------------------------------------------------===// 377// Utilities 378//===----------------------------------------------------------------------===// 379 380/// EmitConversionToBool - Convert the specified expression value to a 381/// boolean (i1) truth value. This is equivalent to "Val != 0". 382Value *ScalarExprEmitter::EmitConversionToBool(Value *Src, QualType SrcType) { 383 assert(SrcType->isCanonical() && "EmitScalarConversion strips typedefs"); 384 385 if (SrcType->isRealFloatingType()) { 386 // Compare against 0.0 for fp scalars. 387 llvm::Value *Zero = CGF.getLLVMContext().getNullValue(Src->getType()); 388 return Builder.CreateFCmpUNE(Src, Zero, "tobool"); 389 } 390 391 assert((SrcType->isIntegerType() || isa<llvm::PointerType>(Src->getType())) && 392 "Unknown scalar type to convert"); 393 394 // Because of the type rules of C, we often end up computing a logical value, 395 // then zero extending it to int, then wanting it as a logical value again. 396 // Optimize this common case. 397 if (llvm::ZExtInst *ZI = dyn_cast<llvm::ZExtInst>(Src)) { 398 if (ZI->getOperand(0)->getType() == llvm::Type::Int1Ty) { 399 Value *Result = ZI->getOperand(0); 400 // If there aren't any more uses, zap the instruction to save space. 401 // Note that there can be more uses, for example if this 402 // is the result of an assignment. 403 if (ZI->use_empty()) 404 ZI->eraseFromParent(); 405 return Result; 406 } 407 } 408 409 // Compare against an integer or pointer null. 410 llvm::Value *Zero = CGF.getLLVMContext().getNullValue(Src->getType()); 411 return Builder.CreateICmpNE(Src, Zero, "tobool"); 412} 413 414/// EmitScalarConversion - Emit a conversion from the specified type to the 415/// specified destination type, both of which are LLVM scalar types. 416Value *ScalarExprEmitter::EmitScalarConversion(Value *Src, QualType SrcType, 417 QualType DstType) { 418 SrcType = CGF.getContext().getCanonicalType(SrcType); 419 DstType = CGF.getContext().getCanonicalType(DstType); 420 if (SrcType == DstType) return Src; 421 422 if (DstType->isVoidType()) return 0; 423 424 // Handle conversions to bool first, they are special: comparisons against 0. 425 if (DstType->isBooleanType()) 426 return EmitConversionToBool(Src, SrcType); 427 428 const llvm::Type *DstTy = ConvertType(DstType); 429 430 // Ignore conversions like int -> uint. 431 if (Src->getType() == DstTy) 432 return Src; 433 434 // Handle pointer conversions next: pointers can only be converted 435 // to/from other pointers and integers. Check for pointer types in 436 // terms of LLVM, as some native types (like Obj-C id) may map to a 437 // pointer type. 438 if (isa<llvm::PointerType>(DstTy)) { 439 // The source value may be an integer, or a pointer. 440 if (isa<llvm::PointerType>(Src->getType())) 441 return Builder.CreateBitCast(Src, DstTy, "conv"); 442 assert(SrcType->isIntegerType() && "Not ptr->ptr or int->ptr conversion?"); 443 // First, convert to the correct width so that we control the kind of 444 // extension. 445 const llvm::Type *MiddleTy = llvm::IntegerType::get(CGF.LLVMPointerWidth); 446 bool InputSigned = SrcType->isSignedIntegerType(); 447 llvm::Value* IntResult = 448 Builder.CreateIntCast(Src, MiddleTy, InputSigned, "conv"); 449 // Then, cast to pointer. 450 return Builder.CreateIntToPtr(IntResult, DstTy, "conv"); 451 } 452 453 if (isa<llvm::PointerType>(Src->getType())) { 454 // Must be an ptr to int cast. 455 assert(isa<llvm::IntegerType>(DstTy) && "not ptr->int?"); 456 return Builder.CreatePtrToInt(Src, DstTy, "conv"); 457 } 458 459 // A scalar can be splatted to an extended vector of the same element type 460 if (DstType->isExtVectorType() && !isa<VectorType>(SrcType)) { 461 // Cast the scalar to element type 462 QualType EltTy = DstType->getAsExtVectorType()->getElementType(); 463 llvm::Value *Elt = EmitScalarConversion(Src, SrcType, EltTy); 464 465 // Insert the element in element zero of an undef vector 466 llvm::Value *UnV = llvm::UndefValue::get(DstTy); 467 llvm::Value *Idx = llvm::ConstantInt::get(llvm::Type::Int32Ty, 0); 468 UnV = Builder.CreateInsertElement(UnV, Elt, Idx, "tmp"); 469 470 // Splat the element across to all elements 471 llvm::SmallVector<llvm::Constant*, 16> Args; 472 unsigned NumElements = cast<llvm::VectorType>(DstTy)->getNumElements(); 473 for (unsigned i = 0; i < NumElements; i++) 474 Args.push_back(llvm::ConstantInt::get(llvm::Type::Int32Ty, 0)); 475 476 llvm::Constant *Mask = llvm::ConstantVector::get(&Args[0], NumElements); 477 llvm::Value *Yay = Builder.CreateShuffleVector(UnV, UnV, Mask, "splat"); 478 return Yay; 479 } 480 481 // Allow bitcast from vector to integer/fp of the same size. 482 if (isa<llvm::VectorType>(Src->getType()) || 483 isa<llvm::VectorType>(DstTy)) 484 return Builder.CreateBitCast(Src, DstTy, "conv"); 485 486 // Finally, we have the arithmetic types: real int/float. 487 if (isa<llvm::IntegerType>(Src->getType())) { 488 bool InputSigned = SrcType->isSignedIntegerType(); 489 if (isa<llvm::IntegerType>(DstTy)) 490 return Builder.CreateIntCast(Src, DstTy, InputSigned, "conv"); 491 else if (InputSigned) 492 return Builder.CreateSIToFP(Src, DstTy, "conv"); 493 else 494 return Builder.CreateUIToFP(Src, DstTy, "conv"); 495 } 496 497 assert(Src->getType()->isFloatingPoint() && "Unknown real conversion"); 498 if (isa<llvm::IntegerType>(DstTy)) { 499 if (DstType->isSignedIntegerType()) 500 return Builder.CreateFPToSI(Src, DstTy, "conv"); 501 else 502 return Builder.CreateFPToUI(Src, DstTy, "conv"); 503 } 504 505 assert(DstTy->isFloatingPoint() && "Unknown real conversion"); 506 if (DstTy->getTypeID() < Src->getType()->getTypeID()) 507 return Builder.CreateFPTrunc(Src, DstTy, "conv"); 508 else 509 return Builder.CreateFPExt(Src, DstTy, "conv"); 510} 511 512/// EmitComplexToScalarConversion - Emit a conversion from the specified 513/// complex type to the specified destination type, where the destination 514/// type is an LLVM scalar type. 515Value *ScalarExprEmitter:: 516EmitComplexToScalarConversion(CodeGenFunction::ComplexPairTy Src, 517 QualType SrcTy, QualType DstTy) { 518 // Get the source element type. 519 SrcTy = SrcTy->getAsComplexType()->getElementType(); 520 521 // Handle conversions to bool first, they are special: comparisons against 0. 522 if (DstTy->isBooleanType()) { 523 // Complex != 0 -> (Real != 0) | (Imag != 0) 524 Src.first = EmitScalarConversion(Src.first, SrcTy, DstTy); 525 Src.second = EmitScalarConversion(Src.second, SrcTy, DstTy); 526 return Builder.CreateOr(Src.first, Src.second, "tobool"); 527 } 528 529 // C99 6.3.1.7p2: "When a value of complex type is converted to a real type, 530 // the imaginary part of the complex value is discarded and the value of the 531 // real part is converted according to the conversion rules for the 532 // corresponding real type. 533 return EmitScalarConversion(Src.first, SrcTy, DstTy); 534} 535 536 537//===----------------------------------------------------------------------===// 538// Visitor Methods 539//===----------------------------------------------------------------------===// 540 541Value *ScalarExprEmitter::VisitExpr(Expr *E) { 542 CGF.ErrorUnsupported(E, "scalar expression"); 543 if (E->getType()->isVoidType()) 544 return 0; 545 return llvm::UndefValue::get(CGF.ConvertType(E->getType())); 546} 547 548Value *ScalarExprEmitter::VisitShuffleVectorExpr(ShuffleVectorExpr *E) { 549 llvm::SmallVector<llvm::Constant*, 32> indices; 550 for (unsigned i = 2; i < E->getNumSubExprs(); i++) { 551 indices.push_back(cast<llvm::Constant>(CGF.EmitScalarExpr(E->getExpr(i)))); 552 } 553 Value* V1 = CGF.EmitScalarExpr(E->getExpr(0)); 554 Value* V2 = CGF.EmitScalarExpr(E->getExpr(1)); 555 Value* SV = llvm::ConstantVector::get(indices.begin(), indices.size()); 556 return Builder.CreateShuffleVector(V1, V2, SV, "shuffle"); 557} 558 559Value *ScalarExprEmitter::VisitArraySubscriptExpr(ArraySubscriptExpr *E) { 560 TestAndClearIgnoreResultAssign(); 561 562 // Emit subscript expressions in rvalue context's. For most cases, this just 563 // loads the lvalue formed by the subscript expr. However, we have to be 564 // careful, because the base of a vector subscript is occasionally an rvalue, 565 // so we can't get it as an lvalue. 566 if (!E->getBase()->getType()->isVectorType()) 567 return EmitLoadOfLValue(E); 568 569 // Handle the vector case. The base must be a vector, the index must be an 570 // integer value. 571 Value *Base = Visit(E->getBase()); 572 Value *Idx = Visit(E->getIdx()); 573 bool IdxSigned = E->getIdx()->getType()->isSignedIntegerType(); 574 Idx = Builder.CreateIntCast(Idx, llvm::Type::Int32Ty, IdxSigned, 575 "vecidxcast"); 576 return Builder.CreateExtractElement(Base, Idx, "vecext"); 577} 578 579/// VisitImplicitCastExpr - Implicit casts are the same as normal casts, but 580/// also handle things like function to pointer-to-function decay, and array to 581/// pointer decay. 582Value *ScalarExprEmitter::VisitImplicitCastExpr(const ImplicitCastExpr *E) { 583 const Expr *Op = E->getSubExpr(); 584 585 // If this is due to array->pointer conversion, emit the array expression as 586 // an l-value. 587 if (Op->getType()->isArrayType()) { 588 Value *V = EmitLValue(Op).getAddress(); // Bitfields can't be arrays. 589 590 // Note that VLA pointers are always decayed, so we don't need to do 591 // anything here. 592 if (!Op->getType()->isVariableArrayType()) { 593 assert(isa<llvm::PointerType>(V->getType()) && "Expected pointer"); 594 assert(isa<llvm::ArrayType>(cast<llvm::PointerType>(V->getType()) 595 ->getElementType()) && 596 "Expected pointer to array"); 597 V = Builder.CreateStructGEP(V, 0, "arraydecay"); 598 } 599 600 // The resultant pointer type can be implicitly casted to other pointer 601 // types as well (e.g. void*) and can be implicitly converted to integer. 602 const llvm::Type *DestTy = ConvertType(E->getType()); 603 if (V->getType() != DestTy) { 604 if (isa<llvm::PointerType>(DestTy)) 605 V = Builder.CreateBitCast(V, DestTy, "ptrconv"); 606 else { 607 assert(isa<llvm::IntegerType>(DestTy) && "Unknown array decay"); 608 V = Builder.CreatePtrToInt(V, DestTy, "ptrconv"); 609 } 610 } 611 return V; 612 } 613 614 return EmitCastExpr(Op, E->getType()); 615} 616 617 618// VisitCastExpr - Emit code for an explicit or implicit cast. Implicit casts 619// have to handle a more broad range of conversions than explicit casts, as they 620// handle things like function to ptr-to-function decay etc. 621Value *ScalarExprEmitter::EmitCastExpr(const Expr *E, QualType DestTy) { 622 if (!DestTy->isVoidType()) 623 TestAndClearIgnoreResultAssign(); 624 625 // Handle cases where the source is an non-complex type. 626 627 if (!CGF.hasAggregateLLVMType(E->getType())) { 628 Value *Src = Visit(const_cast<Expr*>(E)); 629 630 // Use EmitScalarConversion to perform the conversion. 631 return EmitScalarConversion(Src, E->getType(), DestTy); 632 } 633 634 if (E->getType()->isAnyComplexType()) { 635 // Handle cases where the source is a complex type. 636 bool IgnoreImag = true; 637 bool IgnoreImagAssign = true; 638 bool IgnoreReal = IgnoreResultAssign; 639 bool IgnoreRealAssign = IgnoreResultAssign; 640 if (DestTy->isBooleanType()) 641 IgnoreImagAssign = IgnoreImag = false; 642 else if (DestTy->isVoidType()) { 643 IgnoreReal = IgnoreImag = false; 644 IgnoreRealAssign = IgnoreImagAssign = true; 645 } 646 CodeGenFunction::ComplexPairTy V 647 = CGF.EmitComplexExpr(E, IgnoreReal, IgnoreImag, IgnoreRealAssign, 648 IgnoreImagAssign); 649 return EmitComplexToScalarConversion(V, E->getType(), DestTy); 650 } 651 652 // Okay, this is a cast from an aggregate. It must be a cast to void. Just 653 // evaluate the result and return. 654 CGF.EmitAggExpr(E, 0, false, true); 655 return 0; 656} 657 658Value *ScalarExprEmitter::VisitStmtExpr(const StmtExpr *E) { 659 return CGF.EmitCompoundStmt(*E->getSubStmt(), 660 !E->getType()->isVoidType()).getScalarVal(); 661} 662 663Value *ScalarExprEmitter::VisitBlockDeclRefExpr(const BlockDeclRefExpr *E) { 664 return Builder.CreateLoad(CGF.GetAddrOfBlockDecl(E), false, "tmp"); 665} 666 667//===----------------------------------------------------------------------===// 668// Unary Operators 669//===----------------------------------------------------------------------===// 670 671Value *ScalarExprEmitter::VisitPrePostIncDec(const UnaryOperator *E, 672 bool isInc, bool isPre) { 673 LValue LV = EmitLValue(E->getSubExpr()); 674 QualType ValTy = E->getSubExpr()->getType(); 675 Value *InVal = CGF.EmitLoadOfLValue(LV, ValTy).getScalarVal(); 676 677 int AmountVal = isInc ? 1 : -1; 678 679 if (ValTy->isPointerType() && 680 ValTy->getAsPointerType()->isVariableArrayType()) { 681 // The amount of the addition/subtraction needs to account for the VLA size 682 CGF.ErrorUnsupported(E, "VLA pointer inc/dec"); 683 } 684 685 Value *NextVal; 686 if (const llvm::PointerType *PT = 687 dyn_cast<llvm::PointerType>(InVal->getType())) { 688 llvm::Constant *Inc =llvm::ConstantInt::get(llvm::Type::Int32Ty, AmountVal); 689 if (!isa<llvm::FunctionType>(PT->getElementType())) { 690 NextVal = Builder.CreateGEP(InVal, Inc, "ptrincdec"); 691 } else { 692 const llvm::Type *i8Ty = llvm::PointerType::getUnqual(llvm::Type::Int8Ty); 693 NextVal = Builder.CreateBitCast(InVal, i8Ty, "tmp"); 694 NextVal = Builder.CreateGEP(NextVal, Inc, "ptrincdec"); 695 NextVal = Builder.CreateBitCast(NextVal, InVal->getType()); 696 } 697 } else if (InVal->getType() == llvm::Type::Int1Ty && isInc) { 698 // Bool++ is an interesting case, due to promotion rules, we get: 699 // Bool++ -> Bool = Bool+1 -> Bool = (int)Bool+1 -> 700 // Bool = ((int)Bool+1) != 0 701 // An interesting aspect of this is that increment is always true. 702 // Decrement does not have this property. 703 NextVal = llvm::ConstantInt::getTrue(); 704 } else if (isa<llvm::IntegerType>(InVal->getType())) { 705 NextVal = llvm::ConstantInt::get(InVal->getType(), AmountVal); 706 NextVal = Builder.CreateAdd(InVal, NextVal, isInc ? "inc" : "dec"); 707 } else { 708 // Add the inc/dec to the real part. 709 if (InVal->getType() == llvm::Type::FloatTy) 710 NextVal = 711 llvm::ConstantFP::get(llvm::APFloat(static_cast<float>(AmountVal))); 712 else if (InVal->getType() == llvm::Type::DoubleTy) 713 NextVal = 714 llvm::ConstantFP::get(llvm::APFloat(static_cast<double>(AmountVal))); 715 else { 716 llvm::APFloat F(static_cast<float>(AmountVal)); 717 bool ignored; 718 F.convert(CGF.Target.getLongDoubleFormat(), llvm::APFloat::rmTowardZero, 719 &ignored); 720 NextVal = llvm::ConstantFP::get(F); 721 } 722 NextVal = Builder.CreateFAdd(InVal, NextVal, isInc ? "inc" : "dec"); 723 } 724 725 // Store the updated result through the lvalue. 726 if (LV.isBitfield()) 727 CGF.EmitStoreThroughBitfieldLValue(RValue::get(NextVal), LV, ValTy, 728 &NextVal); 729 else 730 CGF.EmitStoreThroughLValue(RValue::get(NextVal), LV, ValTy); 731 732 // If this is a postinc, return the value read from memory, otherwise use the 733 // updated value. 734 return isPre ? NextVal : InVal; 735} 736 737 738Value *ScalarExprEmitter::VisitUnaryMinus(const UnaryOperator *E) { 739 TestAndClearIgnoreResultAssign(); 740 Value *Op = Visit(E->getSubExpr()); 741 if (Op->getType()->isFPOrFPVector()) 742 return Builder.CreateFNeg(Op, "neg"); 743 return Builder.CreateNeg(Op, "neg"); 744} 745 746Value *ScalarExprEmitter::VisitUnaryNot(const UnaryOperator *E) { 747 TestAndClearIgnoreResultAssign(); 748 Value *Op = Visit(E->getSubExpr()); 749 return Builder.CreateNot(Op, "neg"); 750} 751 752Value *ScalarExprEmitter::VisitUnaryLNot(const UnaryOperator *E) { 753 // Compare operand to zero. 754 Value *BoolVal = CGF.EvaluateExprAsBool(E->getSubExpr()); 755 756 // Invert value. 757 // TODO: Could dynamically modify easy computations here. For example, if 758 // the operand is an icmp ne, turn into icmp eq. 759 BoolVal = Builder.CreateNot(BoolVal, "lnot"); 760 761 // ZExt result to the expr type. 762 return Builder.CreateZExt(BoolVal, ConvertType(E->getType()), "lnot.ext"); 763} 764 765/// VisitSizeOfAlignOfExpr - Return the size or alignment of the type of 766/// argument of the sizeof expression as an integer. 767Value * 768ScalarExprEmitter::VisitSizeOfAlignOfExpr(const SizeOfAlignOfExpr *E) { 769 QualType TypeToSize = E->getTypeOfArgument(); 770 if (E->isSizeOf()) { 771 if (const VariableArrayType *VAT = 772 CGF.getContext().getAsVariableArrayType(TypeToSize)) { 773 if (E->isArgumentType()) { 774 // sizeof(type) - make sure to emit the VLA size. 775 CGF.EmitVLASize(TypeToSize); 776 } else { 777 // C99 6.5.3.4p2: If the argument is an expression of type 778 // VLA, it is evaluated. 779 CGF.EmitAnyExpr(E->getArgumentExpr()); 780 } 781 782 return CGF.GetVLASize(VAT); 783 } 784 } 785 786 // If this isn't sizeof(vla), the result must be constant; use the 787 // constant folding logic so we don't have to duplicate it here. 788 Expr::EvalResult Result; 789 E->Evaluate(Result, CGF.getContext()); 790 return llvm::ConstantInt::get(Result.Val.getInt()); 791} 792 793Value *ScalarExprEmitter::VisitUnaryReal(const UnaryOperator *E) { 794 Expr *Op = E->getSubExpr(); 795 if (Op->getType()->isAnyComplexType()) 796 return CGF.EmitComplexExpr(Op, false, true, false, true).first; 797 return Visit(Op); 798} 799Value *ScalarExprEmitter::VisitUnaryImag(const UnaryOperator *E) { 800 Expr *Op = E->getSubExpr(); 801 if (Op->getType()->isAnyComplexType()) 802 return CGF.EmitComplexExpr(Op, true, false, true, false).second; 803 804 // __imag on a scalar returns zero. Emit the subexpr to ensure side 805 // effects are evaluated, but not the actual value. 806 if (E->isLvalue(CGF.getContext()) == Expr::LV_Valid) 807 CGF.EmitLValue(Op); 808 else 809 CGF.EmitScalarExpr(Op, true); 810 return CGF.getLLVMContext().getNullValue(ConvertType(E->getType())); 811} 812 813Value *ScalarExprEmitter::VisitUnaryOffsetOf(const UnaryOperator *E) 814{ 815 Value* ResultAsPtr = EmitLValue(E->getSubExpr()).getAddress(); 816 const llvm::Type* ResultType = ConvertType(E->getType()); 817 return Builder.CreatePtrToInt(ResultAsPtr, ResultType, "offsetof"); 818} 819 820//===----------------------------------------------------------------------===// 821// Binary Operators 822//===----------------------------------------------------------------------===// 823 824BinOpInfo ScalarExprEmitter::EmitBinOps(const BinaryOperator *E) { 825 TestAndClearIgnoreResultAssign(); 826 BinOpInfo Result; 827 Result.LHS = Visit(E->getLHS()); 828 Result.RHS = Visit(E->getRHS()); 829 Result.Ty = E->getType(); 830 Result.E = E; 831 return Result; 832} 833 834Value *ScalarExprEmitter::EmitCompoundAssign(const CompoundAssignOperator *E, 835 Value *(ScalarExprEmitter::*Func)(const BinOpInfo &)) { 836 bool Ignore = TestAndClearIgnoreResultAssign(); 837 QualType LHSTy = E->getLHS()->getType(), RHSTy = E->getRHS()->getType(); 838 839 BinOpInfo OpInfo; 840 841 if (E->getComputationResultType()->isAnyComplexType()) { 842 // This needs to go through the complex expression emitter, but 843 // it's a tad complicated to do that... I'm leaving it out for now. 844 // (Note that we do actually need the imaginary part of the RHS for 845 // multiplication and division.) 846 CGF.ErrorUnsupported(E, "complex compound assignment"); 847 return llvm::UndefValue::get(CGF.ConvertType(E->getType())); 848 } 849 850 // Emit the RHS first. __block variables need to have the rhs evaluated 851 // first, plus this should improve codegen a little. 852 OpInfo.RHS = Visit(E->getRHS()); 853 OpInfo.Ty = E->getComputationResultType(); 854 OpInfo.E = E; 855 // Load/convert the LHS. 856 LValue LHSLV = EmitLValue(E->getLHS()); 857 OpInfo.LHS = EmitLoadOfLValue(LHSLV, LHSTy); 858 OpInfo.LHS = EmitScalarConversion(OpInfo.LHS, LHSTy, 859 E->getComputationLHSType()); 860 861 // Expand the binary operator. 862 Value *Result = (this->*Func)(OpInfo); 863 864 // Convert the result back to the LHS type. 865 Result = EmitScalarConversion(Result, E->getComputationResultType(), LHSTy); 866 867 // Store the result value into the LHS lvalue. Bit-fields are 868 // handled specially because the result is altered by the store, 869 // i.e., [C99 6.5.16p1] 'An assignment expression has the value of 870 // the left operand after the assignment...'. 871 if (LHSLV.isBitfield()) { 872 if (!LHSLV.isVolatileQualified()) { 873 CGF.EmitStoreThroughBitfieldLValue(RValue::get(Result), LHSLV, LHSTy, 874 &Result); 875 return Result; 876 } else 877 CGF.EmitStoreThroughBitfieldLValue(RValue::get(Result), LHSLV, LHSTy); 878 } else 879 CGF.EmitStoreThroughLValue(RValue::get(Result), LHSLV, LHSTy); 880 if (Ignore) 881 return 0; 882 return EmitLoadOfLValue(LHSLV, E->getType()); 883} 884 885 886Value *ScalarExprEmitter::EmitDiv(const BinOpInfo &Ops) { 887 if (Ops.LHS->getType()->isFPOrFPVector()) 888 return Builder.CreateFDiv(Ops.LHS, Ops.RHS, "div"); 889 else if (Ops.Ty->isUnsignedIntegerType()) 890 return Builder.CreateUDiv(Ops.LHS, Ops.RHS, "div"); 891 else 892 return Builder.CreateSDiv(Ops.LHS, Ops.RHS, "div"); 893} 894 895Value *ScalarExprEmitter::EmitRem(const BinOpInfo &Ops) { 896 // Rem in C can't be a floating point type: C99 6.5.5p2. 897 if (Ops.Ty->isUnsignedIntegerType()) 898 return Builder.CreateURem(Ops.LHS, Ops.RHS, "rem"); 899 else 900 return Builder.CreateSRem(Ops.LHS, Ops.RHS, "rem"); 901} 902 903Value *ScalarExprEmitter::EmitOverflowCheckedBinOp(const BinOpInfo &Ops) { 904 unsigned IID; 905 unsigned OpID = 0; 906 907 switch (Ops.E->getOpcode()) { 908 case BinaryOperator::Add: 909 case BinaryOperator::AddAssign: 910 OpID = 1; 911 IID = llvm::Intrinsic::sadd_with_overflow; 912 break; 913 case BinaryOperator::Sub: 914 case BinaryOperator::SubAssign: 915 OpID = 2; 916 IID = llvm::Intrinsic::ssub_with_overflow; 917 break; 918 case BinaryOperator::Mul: 919 case BinaryOperator::MulAssign: 920 OpID = 3; 921 IID = llvm::Intrinsic::smul_with_overflow; 922 break; 923 default: 924 assert(false && "Unsupported operation for overflow detection"); 925 IID = 0; 926 } 927 OpID <<= 1; 928 OpID |= 1; 929 930 const llvm::Type *opTy = CGF.CGM.getTypes().ConvertType(Ops.Ty); 931 932 llvm::Function *intrinsic = CGF.CGM.getIntrinsic(IID, &opTy, 1); 933 934 Value *resultAndOverflow = Builder.CreateCall2(intrinsic, Ops.LHS, Ops.RHS); 935 Value *result = Builder.CreateExtractValue(resultAndOverflow, 0); 936 Value *overflow = Builder.CreateExtractValue(resultAndOverflow, 1); 937 938 // Branch in case of overflow. 939 llvm::BasicBlock *initialBB = Builder.GetInsertBlock(); 940 llvm::BasicBlock *overflowBB = 941 CGF.createBasicBlock("overflow", CGF.CurFn); 942 llvm::BasicBlock *continueBB = 943 CGF.createBasicBlock("overflow.continue", CGF.CurFn); 944 945 Builder.CreateCondBr(overflow, overflowBB, continueBB); 946 947 // Handle overflow 948 949 Builder.SetInsertPoint(overflowBB); 950 951 // Handler is: 952 // long long *__overflow_handler)(long long a, long long b, char op, 953 // char width) 954 std::vector<const llvm::Type*> handerArgTypes; 955 handerArgTypes.push_back(llvm::Type::Int64Ty); 956 handerArgTypes.push_back(llvm::Type::Int64Ty); 957 handerArgTypes.push_back(llvm::Type::Int8Ty); 958 handerArgTypes.push_back(llvm::Type::Int8Ty); 959 llvm::FunctionType *handlerTy = llvm::FunctionType::get(llvm::Type::Int64Ty, 960 handerArgTypes, false); 961 llvm::Value *handlerFunction = 962 CGF.CGM.getModule().getOrInsertGlobal("__overflow_handler", 963 llvm::PointerType::getUnqual(handlerTy)); 964 handlerFunction = Builder.CreateLoad(handlerFunction); 965 966 llvm::Value *handlerResult = Builder.CreateCall4(handlerFunction, 967 Builder.CreateSExt(Ops.LHS, llvm::Type::Int64Ty), 968 Builder.CreateSExt(Ops.RHS, llvm::Type::Int64Ty), 969 llvm::ConstantInt::get(llvm::Type::Int8Ty, OpID), 970 llvm::ConstantInt::get(llvm::Type::Int8Ty, 971 cast<llvm::IntegerType>(opTy)->getBitWidth())); 972 973 handlerResult = Builder.CreateTrunc(handlerResult, opTy); 974 975 Builder.CreateBr(continueBB); 976 977 // Set up the continuation 978 Builder.SetInsertPoint(continueBB); 979 // Get the correct result 980 llvm::PHINode *phi = Builder.CreatePHI(opTy); 981 phi->reserveOperandSpace(2); 982 phi->addIncoming(result, initialBB); 983 phi->addIncoming(handlerResult, overflowBB); 984 985 return phi; 986} 987 988Value *ScalarExprEmitter::EmitAdd(const BinOpInfo &Ops) { 989 if (!Ops.Ty->isAnyPointerType()) { 990 if (CGF.getContext().getLangOptions().OverflowChecking && 991 Ops.Ty->isSignedIntegerType()) 992 return EmitOverflowCheckedBinOp(Ops); 993 994 if (Ops.LHS->getType()->isFPOrFPVector()) 995 return Builder.CreateFAdd(Ops.LHS, Ops.RHS, "add"); 996 997 return Builder.CreateAdd(Ops.LHS, Ops.RHS, "add"); 998 } 999 1000 if (Ops.Ty->isPointerType() && 1001 Ops.Ty->getAsPointerType()->isVariableArrayType()) { 1002 // The amount of the addition needs to account for the VLA size 1003 CGF.ErrorUnsupported(Ops.E, "VLA pointer addition"); 1004 } 1005 Value *Ptr, *Idx; 1006 Expr *IdxExp; 1007 const PointerType *PT = Ops.E->getLHS()->getType()->getAsPointerType(); 1008 const ObjCObjectPointerType *OPT = 1009 Ops.E->getLHS()->getType()->getAsObjCObjectPointerType(); 1010 if (PT || OPT) { 1011 Ptr = Ops.LHS; 1012 Idx = Ops.RHS; 1013 IdxExp = Ops.E->getRHS(); 1014 } else { // int + pointer 1015 PT = Ops.E->getRHS()->getType()->getAsPointerType(); 1016 OPT = Ops.E->getRHS()->getType()->getAsObjCObjectPointerType(); 1017 assert((PT || OPT) && "Invalid add expr"); 1018 Ptr = Ops.RHS; 1019 Idx = Ops.LHS; 1020 IdxExp = Ops.E->getLHS(); 1021 } 1022 1023 unsigned Width = cast<llvm::IntegerType>(Idx->getType())->getBitWidth(); 1024 if (Width < CGF.LLVMPointerWidth) { 1025 // Zero or sign extend the pointer value based on whether the index is 1026 // signed or not. 1027 const llvm::Type *IdxType = llvm::IntegerType::get(CGF.LLVMPointerWidth); 1028 if (IdxExp->getType()->isSignedIntegerType()) 1029 Idx = Builder.CreateSExt(Idx, IdxType, "idx.ext"); 1030 else 1031 Idx = Builder.CreateZExt(Idx, IdxType, "idx.ext"); 1032 } 1033 const QualType ElementType = PT ? PT->getPointeeType() : OPT->getPointeeType(); 1034 // Handle interface types, which are not represented with a concrete 1035 // type. 1036 if (const ObjCInterfaceType *OIT = dyn_cast<ObjCInterfaceType>(ElementType)) { 1037 llvm::Value *InterfaceSize = 1038 llvm::ConstantInt::get(Idx->getType(), 1039 CGF.getContext().getTypeSize(OIT) / 8); 1040 Idx = Builder.CreateMul(Idx, InterfaceSize); 1041 const llvm::Type *i8Ty = llvm::PointerType::getUnqual(llvm::Type::Int8Ty); 1042 Value *Casted = Builder.CreateBitCast(Ptr, i8Ty); 1043 Value *Res = Builder.CreateGEP(Casted, Idx, "add.ptr"); 1044 return Builder.CreateBitCast(Res, Ptr->getType()); 1045 } 1046 1047 // Explicitly handle GNU void* and function pointer arithmetic 1048 // extensions. The GNU void* casts amount to no-ops since our void* 1049 // type is i8*, but this is future proof. 1050 if (ElementType->isVoidType() || ElementType->isFunctionType()) { 1051 const llvm::Type *i8Ty = llvm::PointerType::getUnqual(llvm::Type::Int8Ty); 1052 Value *Casted = Builder.CreateBitCast(Ptr, i8Ty); 1053 Value *Res = Builder.CreateGEP(Casted, Idx, "add.ptr"); 1054 return Builder.CreateBitCast(Res, Ptr->getType()); 1055 } 1056 1057 return Builder.CreateGEP(Ptr, Idx, "add.ptr"); 1058} 1059 1060Value *ScalarExprEmitter::EmitSub(const BinOpInfo &Ops) { 1061 if (!isa<llvm::PointerType>(Ops.LHS->getType())) { 1062 if (CGF.getContext().getLangOptions().OverflowChecking 1063 && Ops.Ty->isSignedIntegerType()) 1064 return EmitOverflowCheckedBinOp(Ops); 1065 1066 if (Ops.LHS->getType()->isFPOrFPVector()) 1067 return Builder.CreateFSub(Ops.LHS, Ops.RHS, "sub"); 1068 return Builder.CreateSub(Ops.LHS, Ops.RHS, "sub"); 1069 } 1070 1071 if (Ops.E->getLHS()->getType()->isPointerType() && 1072 Ops.E->getLHS()->getType()->getAsPointerType()->isVariableArrayType()) { 1073 // The amount of the addition needs to account for the VLA size for 1074 // ptr-int 1075 // The amount of the division needs to account for the VLA size for 1076 // ptr-ptr. 1077 CGF.ErrorUnsupported(Ops.E, "VLA pointer subtraction"); 1078 } 1079 1080 const QualType LHSType = Ops.E->getLHS()->getType(); 1081 const QualType LHSElementType = LHSType->getPointeeType(); 1082 if (!isa<llvm::PointerType>(Ops.RHS->getType())) { 1083 // pointer - int 1084 Value *Idx = Ops.RHS; 1085 unsigned Width = cast<llvm::IntegerType>(Idx->getType())->getBitWidth(); 1086 if (Width < CGF.LLVMPointerWidth) { 1087 // Zero or sign extend the pointer value based on whether the index is 1088 // signed or not. 1089 const llvm::Type *IdxType = llvm::IntegerType::get(CGF.LLVMPointerWidth); 1090 if (Ops.E->getRHS()->getType()->isSignedIntegerType()) 1091 Idx = Builder.CreateSExt(Idx, IdxType, "idx.ext"); 1092 else 1093 Idx = Builder.CreateZExt(Idx, IdxType, "idx.ext"); 1094 } 1095 Idx = Builder.CreateNeg(Idx, "sub.ptr.neg"); 1096 1097 // Handle interface types, which are not represented with a concrete 1098 // type. 1099 if (const ObjCInterfaceType *OIT = 1100 dyn_cast<ObjCInterfaceType>(LHSElementType)) { 1101 llvm::Value *InterfaceSize = 1102 llvm::ConstantInt::get(Idx->getType(), 1103 CGF.getContext().getTypeSize(OIT) / 8); 1104 Idx = Builder.CreateMul(Idx, InterfaceSize); 1105 const llvm::Type *i8Ty = llvm::PointerType::getUnqual(llvm::Type::Int8Ty); 1106 Value *LHSCasted = Builder.CreateBitCast(Ops.LHS, i8Ty); 1107 Value *Res = Builder.CreateGEP(LHSCasted, Idx, "add.ptr"); 1108 return Builder.CreateBitCast(Res, Ops.LHS->getType()); 1109 } 1110 1111 // Explicitly handle GNU void* and function pointer arithmetic 1112 // extensions. The GNU void* casts amount to no-ops since our 1113 // void* type is i8*, but this is future proof. 1114 if (LHSElementType->isVoidType() || LHSElementType->isFunctionType()) { 1115 const llvm::Type *i8Ty = llvm::PointerType::getUnqual(llvm::Type::Int8Ty); 1116 Value *LHSCasted = Builder.CreateBitCast(Ops.LHS, i8Ty); 1117 Value *Res = Builder.CreateGEP(LHSCasted, Idx, "sub.ptr"); 1118 return Builder.CreateBitCast(Res, Ops.LHS->getType()); 1119 } 1120 1121 return Builder.CreateGEP(Ops.LHS, Idx, "sub.ptr"); 1122 } else { 1123 // pointer - pointer 1124 Value *LHS = Ops.LHS; 1125 Value *RHS = Ops.RHS; 1126 1127 uint64_t ElementSize; 1128 1129 // Handle GCC extension for pointer arithmetic on void* and function pointer 1130 // types. 1131 if (LHSElementType->isVoidType() || LHSElementType->isFunctionType()) { 1132 ElementSize = 1; 1133 } else { 1134 ElementSize = CGF.getContext().getTypeSize(LHSElementType) / 8; 1135 } 1136 1137 const llvm::Type *ResultType = ConvertType(Ops.Ty); 1138 LHS = Builder.CreatePtrToInt(LHS, ResultType, "sub.ptr.lhs.cast"); 1139 RHS = Builder.CreatePtrToInt(RHS, ResultType, "sub.ptr.rhs.cast"); 1140 Value *BytesBetween = Builder.CreateSub(LHS, RHS, "sub.ptr.sub"); 1141 1142 // Optimize out the shift for element size of 1. 1143 if (ElementSize == 1) 1144 return BytesBetween; 1145 1146 // HACK: LLVM doesn't have an divide instruction that 'knows' there is no 1147 // remainder. As such, we handle common power-of-two cases here to generate 1148 // better code. See PR2247. 1149 if (llvm::isPowerOf2_64(ElementSize)) { 1150 Value *ShAmt = 1151 llvm::ConstantInt::get(ResultType, llvm::Log2_64(ElementSize)); 1152 return Builder.CreateAShr(BytesBetween, ShAmt, "sub.ptr.shr"); 1153 } 1154 1155 // Otherwise, do a full sdiv. 1156 Value *BytesPerElt = llvm::ConstantInt::get(ResultType, ElementSize); 1157 return Builder.CreateSDiv(BytesBetween, BytesPerElt, "sub.ptr.div"); 1158 } 1159} 1160 1161Value *ScalarExprEmitter::EmitShl(const BinOpInfo &Ops) { 1162 // LLVM requires the LHS and RHS to be the same type: promote or truncate the 1163 // RHS to the same size as the LHS. 1164 Value *RHS = Ops.RHS; 1165 if (Ops.LHS->getType() != RHS->getType()) 1166 RHS = Builder.CreateIntCast(RHS, Ops.LHS->getType(), false, "sh_prom"); 1167 1168 return Builder.CreateShl(Ops.LHS, RHS, "shl"); 1169} 1170 1171Value *ScalarExprEmitter::EmitShr(const BinOpInfo &Ops) { 1172 // LLVM requires the LHS and RHS to be the same type: promote or truncate the 1173 // RHS to the same size as the LHS. 1174 Value *RHS = Ops.RHS; 1175 if (Ops.LHS->getType() != RHS->getType()) 1176 RHS = Builder.CreateIntCast(RHS, Ops.LHS->getType(), false, "sh_prom"); 1177 1178 if (Ops.Ty->isUnsignedIntegerType()) 1179 return Builder.CreateLShr(Ops.LHS, RHS, "shr"); 1180 return Builder.CreateAShr(Ops.LHS, RHS, "shr"); 1181} 1182 1183Value *ScalarExprEmitter::EmitCompare(const BinaryOperator *E,unsigned UICmpOpc, 1184 unsigned SICmpOpc, unsigned FCmpOpc) { 1185 TestAndClearIgnoreResultAssign(); 1186 Value *Result; 1187 QualType LHSTy = E->getLHS()->getType(); 1188 if (!LHSTy->isAnyComplexType()) { 1189 Value *LHS = Visit(E->getLHS()); 1190 Value *RHS = Visit(E->getRHS()); 1191 1192 if (LHS->getType()->isFloatingPoint()) { 1193 Result = Builder.CreateFCmp((llvm::CmpInst::Predicate)FCmpOpc, 1194 LHS, RHS, "cmp"); 1195 } else if (LHSTy->isSignedIntegerType()) { 1196 Result = Builder.CreateICmp((llvm::ICmpInst::Predicate)SICmpOpc, 1197 LHS, RHS, "cmp"); 1198 } else { 1199 // Unsigned integers and pointers. 1200 Result = Builder.CreateICmp((llvm::ICmpInst::Predicate)UICmpOpc, 1201 LHS, RHS, "cmp"); 1202 } 1203 1204 // If this is a vector comparison, sign extend the result to the appropriate 1205 // vector integer type and return it (don't convert to bool). 1206 if (LHSTy->isVectorType()) 1207 return Builder.CreateSExt(Result, ConvertType(E->getType()), "sext"); 1208 1209 } else { 1210 // Complex Comparison: can only be an equality comparison. 1211 CodeGenFunction::ComplexPairTy LHS = CGF.EmitComplexExpr(E->getLHS()); 1212 CodeGenFunction::ComplexPairTy RHS = CGF.EmitComplexExpr(E->getRHS()); 1213 1214 QualType CETy = LHSTy->getAsComplexType()->getElementType(); 1215 1216 Value *ResultR, *ResultI; 1217 if (CETy->isRealFloatingType()) { 1218 ResultR = Builder.CreateFCmp((llvm::FCmpInst::Predicate)FCmpOpc, 1219 LHS.first, RHS.first, "cmp.r"); 1220 ResultI = Builder.CreateFCmp((llvm::FCmpInst::Predicate)FCmpOpc, 1221 LHS.second, RHS.second, "cmp.i"); 1222 } else { 1223 // Complex comparisons can only be equality comparisons. As such, signed 1224 // and unsigned opcodes are the same. 1225 ResultR = Builder.CreateICmp((llvm::ICmpInst::Predicate)UICmpOpc, 1226 LHS.first, RHS.first, "cmp.r"); 1227 ResultI = Builder.CreateICmp((llvm::ICmpInst::Predicate)UICmpOpc, 1228 LHS.second, RHS.second, "cmp.i"); 1229 } 1230 1231 if (E->getOpcode() == BinaryOperator::EQ) { 1232 Result = Builder.CreateAnd(ResultR, ResultI, "and.ri"); 1233 } else { 1234 assert(E->getOpcode() == BinaryOperator::NE && 1235 "Complex comparison other than == or != ?"); 1236 Result = Builder.CreateOr(ResultR, ResultI, "or.ri"); 1237 } 1238 } 1239 1240 return EmitScalarConversion(Result, CGF.getContext().BoolTy, E->getType()); 1241} 1242 1243Value *ScalarExprEmitter::VisitBinAssign(const BinaryOperator *E) { 1244 bool Ignore = TestAndClearIgnoreResultAssign(); 1245 1246 // __block variables need to have the rhs evaluated first, plus this should 1247 // improve codegen just a little. 1248 Value *RHS = Visit(E->getRHS()); 1249 LValue LHS = EmitLValue(E->getLHS()); 1250 1251 // Store the value into the LHS. Bit-fields are handled specially 1252 // because the result is altered by the store, i.e., [C99 6.5.16p1] 1253 // 'An assignment expression has the value of the left operand after 1254 // the assignment...'. 1255 if (LHS.isBitfield()) { 1256 if (!LHS.isVolatileQualified()) { 1257 CGF.EmitStoreThroughBitfieldLValue(RValue::get(RHS), LHS, E->getType(), 1258 &RHS); 1259 return RHS; 1260 } else 1261 CGF.EmitStoreThroughBitfieldLValue(RValue::get(RHS), LHS, E->getType()); 1262 } else 1263 CGF.EmitStoreThroughLValue(RValue::get(RHS), LHS, E->getType()); 1264 if (Ignore) 1265 return 0; 1266 return EmitLoadOfLValue(LHS, E->getType()); 1267} 1268 1269Value *ScalarExprEmitter::VisitBinLAnd(const BinaryOperator *E) { 1270 // If we have 0 && RHS, see if we can elide RHS, if so, just return 0. 1271 // If we have 1 && X, just emit X without inserting the control flow. 1272 if (int Cond = CGF.ConstantFoldsToSimpleInteger(E->getLHS())) { 1273 if (Cond == 1) { // If we have 1 && X, just emit X. 1274 Value *RHSCond = CGF.EvaluateExprAsBool(E->getRHS()); 1275 // ZExt result to int. 1276 return Builder.CreateZExt(RHSCond, CGF.LLVMIntTy, "land.ext"); 1277 } 1278 1279 // 0 && RHS: If it is safe, just elide the RHS, and return 0. 1280 if (!CGF.ContainsLabel(E->getRHS())) 1281 return CGF.getLLVMContext().getNullValue(CGF.LLVMIntTy); 1282 } 1283 1284 llvm::BasicBlock *ContBlock = CGF.createBasicBlock("land.end"); 1285 llvm::BasicBlock *RHSBlock = CGF.createBasicBlock("land.rhs"); 1286 1287 // Branch on the LHS first. If it is false, go to the failure (cont) block. 1288 CGF.EmitBranchOnBoolExpr(E->getLHS(), RHSBlock, ContBlock); 1289 1290 // Any edges into the ContBlock are now from an (indeterminate number of) 1291 // edges from this first condition. All of these values will be false. Start 1292 // setting up the PHI node in the Cont Block for this. 1293 llvm::PHINode *PN = llvm::PHINode::Create(llvm::Type::Int1Ty, "", ContBlock); 1294 PN->reserveOperandSpace(2); // Normal case, two inputs. 1295 for (llvm::pred_iterator PI = pred_begin(ContBlock), PE = pred_end(ContBlock); 1296 PI != PE; ++PI) 1297 PN->addIncoming(llvm::ConstantInt::getFalse(), *PI); 1298 1299 CGF.PushConditionalTempDestruction(); 1300 CGF.EmitBlock(RHSBlock); 1301 Value *RHSCond = CGF.EvaluateExprAsBool(E->getRHS()); 1302 CGF.PopConditionalTempDestruction(); 1303 1304 // Reaquire the RHS block, as there may be subblocks inserted. 1305 RHSBlock = Builder.GetInsertBlock(); 1306 1307 // Emit an unconditional branch from this block to ContBlock. Insert an entry 1308 // into the phi node for the edge with the value of RHSCond. 1309 CGF.EmitBlock(ContBlock); 1310 PN->addIncoming(RHSCond, RHSBlock); 1311 1312 // ZExt result to int. 1313 return Builder.CreateZExt(PN, CGF.LLVMIntTy, "land.ext"); 1314} 1315 1316Value *ScalarExprEmitter::VisitBinLOr(const BinaryOperator *E) { 1317 // If we have 1 || RHS, see if we can elide RHS, if so, just return 1. 1318 // If we have 0 || X, just emit X without inserting the control flow. 1319 if (int Cond = CGF.ConstantFoldsToSimpleInteger(E->getLHS())) { 1320 if (Cond == -1) { // If we have 0 || X, just emit X. 1321 Value *RHSCond = CGF.EvaluateExprAsBool(E->getRHS()); 1322 // ZExt result to int. 1323 return Builder.CreateZExt(RHSCond, CGF.LLVMIntTy, "lor.ext"); 1324 } 1325 1326 // 1 || RHS: If it is safe, just elide the RHS, and return 1. 1327 if (!CGF.ContainsLabel(E->getRHS())) 1328 return llvm::ConstantInt::get(CGF.LLVMIntTy, 1); 1329 } 1330 1331 llvm::BasicBlock *ContBlock = CGF.createBasicBlock("lor.end"); 1332 llvm::BasicBlock *RHSBlock = CGF.createBasicBlock("lor.rhs"); 1333 1334 // Branch on the LHS first. If it is true, go to the success (cont) block. 1335 CGF.EmitBranchOnBoolExpr(E->getLHS(), ContBlock, RHSBlock); 1336 1337 // Any edges into the ContBlock are now from an (indeterminate number of) 1338 // edges from this first condition. All of these values will be true. Start 1339 // setting up the PHI node in the Cont Block for this. 1340 llvm::PHINode *PN = llvm::PHINode::Create(llvm::Type::Int1Ty, "", ContBlock); 1341 PN->reserveOperandSpace(2); // Normal case, two inputs. 1342 for (llvm::pred_iterator PI = pred_begin(ContBlock), PE = pred_end(ContBlock); 1343 PI != PE; ++PI) 1344 PN->addIncoming(llvm::ConstantInt::getTrue(), *PI); 1345 1346 CGF.PushConditionalTempDestruction(); 1347 1348 // Emit the RHS condition as a bool value. 1349 CGF.EmitBlock(RHSBlock); 1350 Value *RHSCond = CGF.EvaluateExprAsBool(E->getRHS()); 1351 1352 CGF.PopConditionalTempDestruction(); 1353 1354 // Reaquire the RHS block, as there may be subblocks inserted. 1355 RHSBlock = Builder.GetInsertBlock(); 1356 1357 // Emit an unconditional branch from this block to ContBlock. Insert an entry 1358 // into the phi node for the edge with the value of RHSCond. 1359 CGF.EmitBlock(ContBlock); 1360 PN->addIncoming(RHSCond, RHSBlock); 1361 1362 // ZExt result to int. 1363 return Builder.CreateZExt(PN, CGF.LLVMIntTy, "lor.ext"); 1364} 1365 1366Value *ScalarExprEmitter::VisitBinComma(const BinaryOperator *E) { 1367 CGF.EmitStmt(E->getLHS()); 1368 CGF.EnsureInsertPoint(); 1369 return Visit(E->getRHS()); 1370} 1371 1372//===----------------------------------------------------------------------===// 1373// Other Operators 1374//===----------------------------------------------------------------------===// 1375 1376/// isCheapEnoughToEvaluateUnconditionally - Return true if the specified 1377/// expression is cheap enough and side-effect-free enough to evaluate 1378/// unconditionally instead of conditionally. This is used to convert control 1379/// flow into selects in some cases. 1380static bool isCheapEnoughToEvaluateUnconditionally(const Expr *E) { 1381 if (const ParenExpr *PE = dyn_cast<ParenExpr>(E)) 1382 return isCheapEnoughToEvaluateUnconditionally(PE->getSubExpr()); 1383 1384 // TODO: Allow anything we can constant fold to an integer or fp constant. 1385 if (isa<IntegerLiteral>(E) || isa<CharacterLiteral>(E) || 1386 isa<FloatingLiteral>(E)) 1387 return true; 1388 1389 // Non-volatile automatic variables too, to get "cond ? X : Y" where 1390 // X and Y are local variables. 1391 if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(E)) 1392 if (const VarDecl *VD = dyn_cast<VarDecl>(DRE->getDecl())) 1393 if (VD->hasLocalStorage() && !VD->getType().isVolatileQualified()) 1394 return true; 1395 1396 return false; 1397} 1398 1399 1400Value *ScalarExprEmitter:: 1401VisitConditionalOperator(const ConditionalOperator *E) { 1402 TestAndClearIgnoreResultAssign(); 1403 // If the condition constant folds and can be elided, try to avoid emitting 1404 // the condition and the dead arm. 1405 if (int Cond = CGF.ConstantFoldsToSimpleInteger(E->getCond())){ 1406 Expr *Live = E->getLHS(), *Dead = E->getRHS(); 1407 if (Cond == -1) 1408 std::swap(Live, Dead); 1409 1410 // If the dead side doesn't have labels we need, and if the Live side isn't 1411 // the gnu missing ?: extension (which we could handle, but don't bother 1412 // to), just emit the Live part. 1413 if ((!Dead || !CGF.ContainsLabel(Dead)) && // No labels in dead part 1414 Live) // Live part isn't missing. 1415 return Visit(Live); 1416 } 1417 1418 1419 // If this is a really simple expression (like x ? 4 : 5), emit this as a 1420 // select instead of as control flow. We can only do this if it is cheap and 1421 // safe to evaluate the LHS and RHS unconditionally. 1422 if (E->getLHS() && isCheapEnoughToEvaluateUnconditionally(E->getLHS()) && 1423 isCheapEnoughToEvaluateUnconditionally(E->getRHS())) { 1424 llvm::Value *CondV = CGF.EvaluateExprAsBool(E->getCond()); 1425 llvm::Value *LHS = Visit(E->getLHS()); 1426 llvm::Value *RHS = Visit(E->getRHS()); 1427 return Builder.CreateSelect(CondV, LHS, RHS, "cond"); 1428 } 1429 1430 1431 llvm::BasicBlock *LHSBlock = CGF.createBasicBlock("cond.true"); 1432 llvm::BasicBlock *RHSBlock = CGF.createBasicBlock("cond.false"); 1433 llvm::BasicBlock *ContBlock = CGF.createBasicBlock("cond.end"); 1434 Value *CondVal = 0; 1435 1436 // If we don't have the GNU missing condition extension, emit a branch on 1437 // bool the normal way. 1438 if (E->getLHS()) { 1439 // Otherwise, just use EmitBranchOnBoolExpr to get small and simple code for 1440 // the branch on bool. 1441 CGF.EmitBranchOnBoolExpr(E->getCond(), LHSBlock, RHSBlock); 1442 } else { 1443 // Otherwise, for the ?: extension, evaluate the conditional and then 1444 // convert it to bool the hard way. We do this explicitly because we need 1445 // the unconverted value for the missing middle value of the ?:. 1446 CondVal = CGF.EmitScalarExpr(E->getCond()); 1447 1448 // In some cases, EmitScalarConversion will delete the "CondVal" expression 1449 // if there are no extra uses (an optimization). Inhibit this by making an 1450 // extra dead use, because we're going to add a use of CondVal later. We 1451 // don't use the builder for this, because we don't want it to get optimized 1452 // away. This leaves dead code, but the ?: extension isn't common. 1453 new llvm::BitCastInst(CondVal, CondVal->getType(), "dummy?:holder", 1454 Builder.GetInsertBlock()); 1455 1456 Value *CondBoolVal = 1457 CGF.EmitScalarConversion(CondVal, E->getCond()->getType(), 1458 CGF.getContext().BoolTy); 1459 Builder.CreateCondBr(CondBoolVal, LHSBlock, RHSBlock); 1460 } 1461 1462 CGF.PushConditionalTempDestruction(); 1463 CGF.EmitBlock(LHSBlock); 1464 1465 // Handle the GNU extension for missing LHS. 1466 Value *LHS; 1467 if (E->getLHS()) 1468 LHS = Visit(E->getLHS()); 1469 else // Perform promotions, to handle cases like "short ?: int" 1470 LHS = EmitScalarConversion(CondVal, E->getCond()->getType(), E->getType()); 1471 1472 CGF.PopConditionalTempDestruction(); 1473 LHSBlock = Builder.GetInsertBlock(); 1474 CGF.EmitBranch(ContBlock); 1475 1476 CGF.PushConditionalTempDestruction(); 1477 CGF.EmitBlock(RHSBlock); 1478 1479 Value *RHS = Visit(E->getRHS()); 1480 CGF.PopConditionalTempDestruction(); 1481 RHSBlock = Builder.GetInsertBlock(); 1482 CGF.EmitBranch(ContBlock); 1483 1484 CGF.EmitBlock(ContBlock); 1485 1486 if (!LHS || !RHS) { 1487 assert(E->getType()->isVoidType() && "Non-void value should have a value"); 1488 return 0; 1489 } 1490 1491 // Create a PHI node for the real part. 1492 llvm::PHINode *PN = Builder.CreatePHI(LHS->getType(), "cond"); 1493 PN->reserveOperandSpace(2); 1494 PN->addIncoming(LHS, LHSBlock); 1495 PN->addIncoming(RHS, RHSBlock); 1496 return PN; 1497} 1498 1499Value *ScalarExprEmitter::VisitChooseExpr(ChooseExpr *E) { 1500 return Visit(E->getChosenSubExpr(CGF.getContext())); 1501} 1502 1503Value *ScalarExprEmitter::VisitVAArgExpr(VAArgExpr *VE) { 1504 llvm::Value *ArgValue = CGF.EmitVAListRef(VE->getSubExpr()); 1505 llvm::Value *ArgPtr = CGF.EmitVAArg(ArgValue, VE->getType()); 1506 1507 // If EmitVAArg fails, we fall back to the LLVM instruction. 1508 if (!ArgPtr) 1509 return Builder.CreateVAArg(ArgValue, ConvertType(VE->getType())); 1510 1511 // FIXME Volatility. 1512 return Builder.CreateLoad(ArgPtr); 1513} 1514 1515Value *ScalarExprEmitter::VisitBlockExpr(const BlockExpr *BE) { 1516 return CGF.BuildBlockLiteralTmp(BE); 1517} 1518 1519//===----------------------------------------------------------------------===// 1520// Entry Point into this File 1521//===----------------------------------------------------------------------===// 1522 1523/// EmitScalarExpr - Emit the computation of the specified expression of 1524/// scalar type, ignoring the result. 1525Value *CodeGenFunction::EmitScalarExpr(const Expr *E, bool IgnoreResultAssign) { 1526 assert(E && !hasAggregateLLVMType(E->getType()) && 1527 "Invalid scalar expression to emit"); 1528 1529 return ScalarExprEmitter(*this, IgnoreResultAssign) 1530 .Visit(const_cast<Expr*>(E)); 1531} 1532 1533/// EmitScalarConversion - Emit a conversion from the specified type to the 1534/// specified destination type, both of which are LLVM scalar types. 1535Value *CodeGenFunction::EmitScalarConversion(Value *Src, QualType SrcTy, 1536 QualType DstTy) { 1537 assert(!hasAggregateLLVMType(SrcTy) && !hasAggregateLLVMType(DstTy) && 1538 "Invalid scalar expression to emit"); 1539 return ScalarExprEmitter(*this).EmitScalarConversion(Src, SrcTy, DstTy); 1540} 1541 1542/// EmitComplexToScalarConversion - Emit a conversion from the specified 1543/// complex type to the specified destination type, where the destination 1544/// type is an LLVM scalar type. 1545Value *CodeGenFunction::EmitComplexToScalarConversion(ComplexPairTy Src, 1546 QualType SrcTy, 1547 QualType DstTy) { 1548 assert(SrcTy->isAnyComplexType() && !hasAggregateLLVMType(DstTy) && 1549 "Invalid complex -> scalar conversion"); 1550 return ScalarExprEmitter(*this).EmitComplexToScalarConversion(Src, SrcTy, 1551 DstTy); 1552} 1553 1554Value *CodeGenFunction::EmitShuffleVector(Value* V1, Value *V2, ...) { 1555 assert(V1->getType() == V2->getType() && 1556 "Vector operands must be of the same type"); 1557 unsigned NumElements = 1558 cast<llvm::VectorType>(V1->getType())->getNumElements(); 1559 1560 va_list va; 1561 va_start(va, V2); 1562 1563 llvm::SmallVector<llvm::Constant*, 16> Args; 1564 for (unsigned i = 0; i < NumElements; i++) { 1565 int n = va_arg(va, int); 1566 assert(n >= 0 && n < (int)NumElements * 2 && 1567 "Vector shuffle index out of bounds!"); 1568 Args.push_back(llvm::ConstantInt::get(llvm::Type::Int32Ty, n)); 1569 } 1570 1571 const char *Name = va_arg(va, const char *); 1572 va_end(va); 1573 1574 llvm::Constant *Mask = llvm::ConstantVector::get(&Args[0], NumElements); 1575 1576 return Builder.CreateShuffleVector(V1, V2, Mask, Name); 1577} 1578 1579llvm::Value *CodeGenFunction::EmitVector(llvm::Value * const *Vals, 1580 unsigned NumVals, bool isSplat) { 1581 llvm::Value *Vec 1582 = llvm::UndefValue::get(llvm::VectorType::get(Vals[0]->getType(), NumVals)); 1583 1584 for (unsigned i = 0, e = NumVals; i != e; ++i) { 1585 llvm::Value *Val = isSplat ? Vals[0] : Vals[i]; 1586 llvm::Value *Idx = llvm::ConstantInt::get(llvm::Type::Int32Ty, i); 1587 Vec = Builder.CreateInsertElement(Vec, Val, Idx, "tmp"); 1588 } 1589 1590 return Vec; 1591} 1592