CGExprScalar.cpp revision af2f62ce32e462f256855cd24b06dec4755d2827
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 "CGObjCRuntime.h" 17#include "clang/AST/ASTContext.h" 18#include "clang/AST/DeclObjC.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/Support/Compiler.h" 26#include <cstdarg> 27 28using namespace clang; 29using namespace CodeGen; 30using llvm::Value; 31 32//===----------------------------------------------------------------------===// 33// Scalar Expression Emitter 34//===----------------------------------------------------------------------===// 35 36struct BinOpInfo { 37 Value *LHS; 38 Value *RHS; 39 QualType Ty; // Computation Type. 40 const BinaryOperator *E; 41}; 42 43namespace { 44class VISIBILITY_HIDDEN ScalarExprEmitter 45 : public StmtVisitor<ScalarExprEmitter, Value*> { 46 CodeGenFunction &CGF; 47 llvm::IRBuilder<> &Builder; 48 CGObjCRuntime *Runtime; 49 50public: 51 52 ScalarExprEmitter(CodeGenFunction &cgf) : CGF(cgf), 53 Builder(CGF.Builder), 54 Runtime(0) { 55 if (CGF.CGM.hasObjCRuntime()) 56 Runtime = &CGF.CGM.getObjCRuntime(); 57 } 58 59 //===--------------------------------------------------------------------===// 60 // Utilities 61 //===--------------------------------------------------------------------===// 62 63 const llvm::Type *ConvertType(QualType T) { return CGF.ConvertType(T); } 64 LValue EmitLValue(const Expr *E) { return CGF.EmitLValue(E); } 65 66 Value *EmitLoadOfLValue(LValue LV, QualType T) { 67 return CGF.EmitLoadOfLValue(LV, T).getScalarVal(); 68 } 69 70 /// EmitLoadOfLValue - Given an expression with complex type that represents a 71 /// value l-value, this method emits the address of the l-value, then loads 72 /// and returns the result. 73 Value *EmitLoadOfLValue(const Expr *E) { 74 // FIXME: Volatile 75 return EmitLoadOfLValue(EmitLValue(E), E->getType()); 76 } 77 78 /// EmitConversionToBool - Convert the specified expression value to a 79 /// boolean (i1) truth value. This is equivalent to "Val != 0". 80 Value *EmitConversionToBool(Value *Src, QualType DstTy); 81 82 /// EmitScalarConversion - Emit a conversion from the specified type to the 83 /// specified destination type, both of which are LLVM scalar types. 84 Value *EmitScalarConversion(Value *Src, QualType SrcTy, QualType DstTy); 85 86 /// EmitComplexToScalarConversion - Emit a conversion from the specified 87 /// complex type to the specified destination type, where the destination 88 /// type is an LLVM scalar type. 89 Value *EmitComplexToScalarConversion(CodeGenFunction::ComplexPairTy Src, 90 QualType SrcTy, QualType DstTy); 91 92 //===--------------------------------------------------------------------===// 93 // Visitor Methods 94 //===--------------------------------------------------------------------===// 95 96 Value *VisitStmt(Stmt *S) { 97 S->dump(CGF.getContext().getSourceManager()); 98 assert(0 && "Stmt can't have complex result type!"); 99 return 0; 100 } 101 Value *VisitExpr(Expr *S); 102 Value *VisitParenExpr(ParenExpr *PE) { return Visit(PE->getSubExpr()); } 103 104 // Leaves. 105 Value *VisitIntegerLiteral(const IntegerLiteral *E) { 106 return llvm::ConstantInt::get(E->getValue()); 107 } 108 Value *VisitFloatingLiteral(const FloatingLiteral *E) { 109 return llvm::ConstantFP::get(E->getValue()); 110 } 111 Value *VisitCharacterLiteral(const CharacterLiteral *E) { 112 return llvm::ConstantInt::get(ConvertType(E->getType()), E->getValue()); 113 } 114 Value *VisitCXXBoolLiteralExpr(const CXXBoolLiteralExpr *E) { 115 return llvm::ConstantInt::get(ConvertType(E->getType()), E->getValue()); 116 } 117 Value *VisitTypesCompatibleExpr(const TypesCompatibleExpr *E) { 118 return llvm::ConstantInt::get(ConvertType(E->getType()), 119 CGF.getContext().typesAreCompatible( 120 E->getArgType1(), E->getArgType2())); 121 } 122 Value *VisitSizeOfAlignOfTypeExpr(const SizeOfAlignOfTypeExpr *E) { 123 return EmitSizeAlignOf(E->getArgumentType(), E->getType(), E->isSizeOf()); 124 } 125 Value *VisitAddrLabelExpr(const AddrLabelExpr *E) { 126 Value *V = llvm::ConstantInt::get(llvm::Type::Int32Ty, 127 CGF.GetIDForAddrOfLabel(E->getLabel())); 128 return Builder.CreateIntToPtr(V, 129 llvm::PointerType::getUnqual(llvm::Type::Int8Ty)); 130 } 131 132 // l-values. 133 Value *VisitDeclRefExpr(DeclRefExpr *E) { 134 if (const EnumConstantDecl *EC = dyn_cast<EnumConstantDecl>(E->getDecl())) 135 return llvm::ConstantInt::get(EC->getInitVal()); 136 return EmitLoadOfLValue(E); 137 } 138 Value *VisitObjCMessageExpr(ObjCMessageExpr *E); 139 Value *VisitObjCSelectorExpr(ObjCSelectorExpr *E); 140 Value *VisitObjCProtocolExpr(ObjCProtocolExpr *E); 141 Value *VisitObjCIvarRefExpr(ObjCIvarRefExpr *E) { return EmitLoadOfLValue(E);} 142 Value *VisitArraySubscriptExpr(ArraySubscriptExpr *E); 143 Value *VisitShuffleVectorExpr(ShuffleVectorExpr *E); 144 Value *VisitMemberExpr(Expr *E) { return EmitLoadOfLValue(E); } 145 Value *VisitExtVectorElementExpr(Expr *E) { return EmitLoadOfLValue(E); } 146 Value *VisitCompoundLiteralExpr(CompoundLiteralExpr *E) { return EmitLoadOfLValue(E); } 147 Value *VisitStringLiteral(Expr *E) { return EmitLValue(E).getAddress(); } 148 Value *VisitPredefinedExpr(Expr *E) { return EmitLValue(E).getAddress(); } 149 150 Value *VisitInitListExpr(InitListExpr *E) { 151 unsigned NumInitElements = E->getNumInits(); 152 153 const llvm::VectorType *VType = 154 dyn_cast<llvm::VectorType>(ConvertType(E->getType())); 155 156 // We have a scalar in braces. Just use the first element. 157 if (!VType) 158 return Visit(E->getInit(0)); 159 160 unsigned NumVectorElements = VType->getNumElements(); 161 const llvm::Type *ElementType = VType->getElementType(); 162 163 // Emit individual vector element stores. 164 llvm::Value *V = llvm::UndefValue::get(VType); 165 166 // Emit initializers 167 unsigned i; 168 for (i = 0; i < NumInitElements; ++i) { 169 Value *NewV = Visit(E->getInit(i)); 170 Value *Idx = llvm::ConstantInt::get(llvm::Type::Int32Ty, i); 171 V = Builder.CreateInsertElement(V, NewV, Idx); 172 } 173 174 // Emit remaining default initializers 175 for (/* Do not initialize i*/; i < NumVectorElements; ++i) { 176 Value *Idx = llvm::ConstantInt::get(llvm::Type::Int32Ty, i); 177 llvm::Value *NewV = llvm::Constant::getNullValue(ElementType); 178 V = Builder.CreateInsertElement(V, NewV, Idx); 179 } 180 181 return V; 182 } 183 184 Value *VisitImplicitCastExpr(const ImplicitCastExpr *E); 185 Value *VisitCastExpr(const CastExpr *E) { 186 return EmitCastExpr(E->getSubExpr(), E->getType()); 187 } 188 Value *EmitCastExpr(const Expr *E, QualType T); 189 190 Value *VisitCallExpr(const CallExpr *E) { 191 return CGF.EmitCallExpr(E).getScalarVal(); 192 } 193 194 Value *VisitStmtExpr(const StmtExpr *E); 195 196 // Unary Operators. 197 Value *VisitPrePostIncDec(const UnaryOperator *E, bool isInc, bool isPre); 198 Value *VisitUnaryPostDec(const UnaryOperator *E) { 199 return VisitPrePostIncDec(E, false, false); 200 } 201 Value *VisitUnaryPostInc(const UnaryOperator *E) { 202 return VisitPrePostIncDec(E, true, false); 203 } 204 Value *VisitUnaryPreDec(const UnaryOperator *E) { 205 return VisitPrePostIncDec(E, false, true); 206 } 207 Value *VisitUnaryPreInc(const UnaryOperator *E) { 208 return VisitPrePostIncDec(E, true, true); 209 } 210 Value *VisitUnaryAddrOf(const UnaryOperator *E) { 211 return EmitLValue(E->getSubExpr()).getAddress(); 212 } 213 Value *VisitUnaryDeref(const Expr *E) { return EmitLoadOfLValue(E); } 214 Value *VisitUnaryPlus(const UnaryOperator *E) { 215 return Visit(E->getSubExpr()); 216 } 217 Value *VisitUnaryMinus (const UnaryOperator *E); 218 Value *VisitUnaryNot (const UnaryOperator *E); 219 Value *VisitUnaryLNot (const UnaryOperator *E); 220 Value *VisitUnarySizeOf (const UnaryOperator *E) { 221 return EmitSizeAlignOf(E->getSubExpr()->getType(), E->getType(), true); 222 } 223 Value *VisitUnaryAlignOf (const UnaryOperator *E) { 224 return EmitSizeAlignOf(E->getSubExpr()->getType(), E->getType(), false); 225 } 226 Value *EmitSizeAlignOf(QualType TypeToSize, QualType RetType, 227 bool isSizeOf); 228 Value *VisitUnaryReal (const UnaryOperator *E); 229 Value *VisitUnaryImag (const UnaryOperator *E); 230 Value *VisitUnaryExtension(const UnaryOperator *E) { 231 return Visit(E->getSubExpr()); 232 } 233 Value *VisitUnaryOffsetOf(const UnaryOperator *E); 234 Value *VisitCXXDefaultArgExpr(CXXDefaultArgExpr *DAE) { 235 return Visit(DAE->getExpr()); 236 } 237 238 // Binary Operators. 239 Value *EmitMul(const BinOpInfo &Ops) { 240 return Builder.CreateMul(Ops.LHS, Ops.RHS, "mul"); 241 } 242 Value *EmitDiv(const BinOpInfo &Ops); 243 Value *EmitRem(const BinOpInfo &Ops); 244 Value *EmitAdd(const BinOpInfo &Ops); 245 Value *EmitSub(const BinOpInfo &Ops); 246 Value *EmitShl(const BinOpInfo &Ops); 247 Value *EmitShr(const BinOpInfo &Ops); 248 Value *EmitAnd(const BinOpInfo &Ops) { 249 return Builder.CreateAnd(Ops.LHS, Ops.RHS, "and"); 250 } 251 Value *EmitXor(const BinOpInfo &Ops) { 252 return Builder.CreateXor(Ops.LHS, Ops.RHS, "xor"); 253 } 254 Value *EmitOr (const BinOpInfo &Ops) { 255 return Builder.CreateOr(Ops.LHS, Ops.RHS, "or"); 256 } 257 258 BinOpInfo EmitBinOps(const BinaryOperator *E); 259 Value *EmitCompoundAssign(const CompoundAssignOperator *E, 260 Value *(ScalarExprEmitter::*F)(const BinOpInfo &)); 261 262 // Binary operators and binary compound assignment operators. 263#define HANDLEBINOP(OP) \ 264 Value *VisitBin ## OP(const BinaryOperator *E) { \ 265 return Emit ## OP(EmitBinOps(E)); \ 266 } \ 267 Value *VisitBin ## OP ## Assign(const CompoundAssignOperator *E) { \ 268 return EmitCompoundAssign(E, &ScalarExprEmitter::Emit ## OP); \ 269 } 270 HANDLEBINOP(Mul); 271 HANDLEBINOP(Div); 272 HANDLEBINOP(Rem); 273 HANDLEBINOP(Add); 274 HANDLEBINOP(Sub); 275 HANDLEBINOP(Shl); 276 HANDLEBINOP(Shr); 277 HANDLEBINOP(And); 278 HANDLEBINOP(Xor); 279 HANDLEBINOP(Or); 280#undef HANDLEBINOP 281 282 // Comparisons. 283 Value *EmitCompare(const BinaryOperator *E, unsigned UICmpOpc, 284 unsigned SICmpOpc, unsigned FCmpOpc); 285#define VISITCOMP(CODE, UI, SI, FP) \ 286 Value *VisitBin##CODE(const BinaryOperator *E) { \ 287 return EmitCompare(E, llvm::ICmpInst::UI, llvm::ICmpInst::SI, \ 288 llvm::FCmpInst::FP); } 289 VISITCOMP(LT, ICMP_ULT, ICMP_SLT, FCMP_OLT); 290 VISITCOMP(GT, ICMP_UGT, ICMP_SGT, FCMP_OGT); 291 VISITCOMP(LE, ICMP_ULE, ICMP_SLE, FCMP_OLE); 292 VISITCOMP(GE, ICMP_UGE, ICMP_SGE, FCMP_OGE); 293 VISITCOMP(EQ, ICMP_EQ , ICMP_EQ , FCMP_OEQ); 294 VISITCOMP(NE, ICMP_NE , ICMP_NE , FCMP_UNE); 295#undef VISITCOMP 296 297 Value *VisitBinAssign (const BinaryOperator *E); 298 299 Value *VisitBinLAnd (const BinaryOperator *E); 300 Value *VisitBinLOr (const BinaryOperator *E); 301 Value *VisitBinComma (const BinaryOperator *E); 302 303 // Other Operators. 304 Value *VisitConditionalOperator(const ConditionalOperator *CO); 305 Value *VisitChooseExpr(ChooseExpr *CE); 306 Value *VisitOverloadExpr(OverloadExpr *OE); 307 Value *VisitVAArgExpr(VAArgExpr *VE); 308 Value *VisitObjCStringLiteral(const ObjCStringLiteral *E) { 309 return CGF.EmitObjCStringLiteral(E); 310 } 311 Value *VisitObjCEncodeExpr(const ObjCEncodeExpr *E); 312}; 313} // end anonymous namespace. 314 315//===----------------------------------------------------------------------===// 316// Utilities 317//===----------------------------------------------------------------------===// 318 319/// EmitConversionToBool - Convert the specified expression value to a 320/// boolean (i1) truth value. This is equivalent to "Val != 0". 321Value *ScalarExprEmitter::EmitConversionToBool(Value *Src, QualType SrcType) { 322 assert(SrcType->isCanonical() && "EmitScalarConversion strips typedefs"); 323 324 if (SrcType->isRealFloatingType()) { 325 // Compare against 0.0 for fp scalars. 326 llvm::Value *Zero = llvm::Constant::getNullValue(Src->getType()); 327 return Builder.CreateFCmpUNE(Src, Zero, "tobool"); 328 } 329 330 assert((SrcType->isIntegerType() || SrcType->isPointerType()) && 331 "Unknown scalar type to convert"); 332 333 // Because of the type rules of C, we often end up computing a logical value, 334 // then zero extending it to int, then wanting it as a logical value again. 335 // Optimize this common case. 336 if (llvm::ZExtInst *ZI = dyn_cast<llvm::ZExtInst>(Src)) { 337 if (ZI->getOperand(0)->getType() == llvm::Type::Int1Ty) { 338 Value *Result = ZI->getOperand(0); 339 // If there aren't any more uses, zap the instruction to save space. 340 // Note that there can be more uses, for example if this 341 // is the result of an assignment. 342 if (ZI->use_empty()) 343 ZI->eraseFromParent(); 344 return Result; 345 } 346 } 347 348 // Compare against an integer or pointer null. 349 llvm::Value *Zero = llvm::Constant::getNullValue(Src->getType()); 350 return Builder.CreateICmpNE(Src, Zero, "tobool"); 351} 352 353/// EmitScalarConversion - Emit a conversion from the specified type to the 354/// specified destination type, both of which are LLVM scalar types. 355Value *ScalarExprEmitter::EmitScalarConversion(Value *Src, QualType SrcType, 356 QualType DstType) { 357 SrcType = CGF.getContext().getCanonicalType(SrcType); 358 DstType = CGF.getContext().getCanonicalType(DstType); 359 if (SrcType == DstType) return Src; 360 361 if (DstType->isVoidType()) return 0; 362 363 // Handle conversions to bool first, they are special: comparisons against 0. 364 if (DstType->isBooleanType()) 365 return EmitConversionToBool(Src, SrcType); 366 367 const llvm::Type *DstTy = ConvertType(DstType); 368 369 // Ignore conversions like int -> uint. 370 if (Src->getType() == DstTy) 371 return Src; 372 373 // Handle pointer conversions next: pointers can only be converted to/from 374 // other pointers and integers. 375 if (isa<PointerType>(DstType)) { 376 // The source value may be an integer, or a pointer. 377 if (isa<llvm::PointerType>(Src->getType())) 378 return Builder.CreateBitCast(Src, DstTy, "conv"); 379 assert(SrcType->isIntegerType() && "Not ptr->ptr or int->ptr conversion?"); 380 return Builder.CreateIntToPtr(Src, DstTy, "conv"); 381 } 382 383 if (isa<PointerType>(SrcType)) { 384 // Must be an ptr to int cast. 385 assert(isa<llvm::IntegerType>(DstTy) && "not ptr->int?"); 386 return Builder.CreatePtrToInt(Src, DstTy, "conv"); 387 } 388 389 // A scalar can be splatted to an extended vector of the same element type 390 if (DstType->isExtVectorType() && !isa<VectorType>(SrcType) && 391 cast<llvm::VectorType>(DstTy)->getElementType() == Src->getType()) 392 return CGF.EmitVector(&Src, DstType->getAsVectorType()->getNumElements(), 393 true); 394 395 // Allow bitcast from vector to integer/fp of the same size. 396 if (isa<llvm::VectorType>(Src->getType()) || 397 isa<llvm::VectorType>(DstTy)) 398 return Builder.CreateBitCast(Src, DstTy, "conv"); 399 400 // Finally, we have the arithmetic types: real int/float. 401 if (isa<llvm::IntegerType>(Src->getType())) { 402 bool InputSigned = SrcType->isSignedIntegerType(); 403 if (isa<llvm::IntegerType>(DstTy)) 404 return Builder.CreateIntCast(Src, DstTy, InputSigned, "conv"); 405 else if (InputSigned) 406 return Builder.CreateSIToFP(Src, DstTy, "conv"); 407 else 408 return Builder.CreateUIToFP(Src, DstTy, "conv"); 409 } 410 411 assert(Src->getType()->isFloatingPoint() && "Unknown real conversion"); 412 if (isa<llvm::IntegerType>(DstTy)) { 413 if (DstType->isSignedIntegerType()) 414 return Builder.CreateFPToSI(Src, DstTy, "conv"); 415 else 416 return Builder.CreateFPToUI(Src, DstTy, "conv"); 417 } 418 419 assert(DstTy->isFloatingPoint() && "Unknown real conversion"); 420 if (DstTy->getTypeID() < Src->getType()->getTypeID()) 421 return Builder.CreateFPTrunc(Src, DstTy, "conv"); 422 else 423 return Builder.CreateFPExt(Src, DstTy, "conv"); 424} 425 426/// EmitComplexToScalarConversion - Emit a conversion from the specified 427/// complex type to the specified destination type, where the destination 428/// type is an LLVM scalar type. 429Value *ScalarExprEmitter:: 430EmitComplexToScalarConversion(CodeGenFunction::ComplexPairTy Src, 431 QualType SrcTy, QualType DstTy) { 432 // Get the source element type. 433 SrcTy = SrcTy->getAsComplexType()->getElementType(); 434 435 // Handle conversions to bool first, they are special: comparisons against 0. 436 if (DstTy->isBooleanType()) { 437 // Complex != 0 -> (Real != 0) | (Imag != 0) 438 Src.first = EmitScalarConversion(Src.first, SrcTy, DstTy); 439 Src.second = EmitScalarConversion(Src.second, SrcTy, DstTy); 440 return Builder.CreateOr(Src.first, Src.second, "tobool"); 441 } 442 443 // C99 6.3.1.7p2: "When a value of complex type is converted to a real type, 444 // the imaginary part of the complex value is discarded and the value of the 445 // real part is converted according to the conversion rules for the 446 // corresponding real type. 447 return EmitScalarConversion(Src.first, SrcTy, DstTy); 448} 449 450 451//===----------------------------------------------------------------------===// 452// Visitor Methods 453//===----------------------------------------------------------------------===// 454 455Value *ScalarExprEmitter::VisitExpr(Expr *E) { 456 CGF.WarnUnsupported(E, "scalar expression"); 457 if (E->getType()->isVoidType()) 458 return 0; 459 return llvm::UndefValue::get(CGF.ConvertType(E->getType())); 460} 461 462Value *ScalarExprEmitter::VisitShuffleVectorExpr(ShuffleVectorExpr *E) { 463 llvm::SmallVector<llvm::Constant*, 32> indices; 464 for (unsigned i = 2; i < E->getNumSubExprs(); i++) { 465 indices.push_back(cast<llvm::Constant>(CGF.EmitScalarExpr(E->getExpr(i)))); 466 } 467 Value* V1 = CGF.EmitScalarExpr(E->getExpr(0)); 468 Value* V2 = CGF.EmitScalarExpr(E->getExpr(1)); 469 Value* SV = llvm::ConstantVector::get(indices.begin(), indices.size()); 470 return Builder.CreateShuffleVector(V1, V2, SV, "shuffle"); 471} 472 473Value *ScalarExprEmitter::VisitObjCMessageExpr(ObjCMessageExpr *E) { 474 // Only the lookup mechanism and first two arguments of the method 475 // implementation vary between runtimes. We can get the receiver and 476 // arguments in generic code. 477 478 // Find the receiver 479 llvm::Value *Receiver = CGF.EmitScalarExpr(E->getReceiver()); 480 481 // Process the arguments 482 unsigned ArgC = E->getNumArgs(); 483 llvm::SmallVector<llvm::Value*, 16> Args; 484 for (unsigned i = 0; i != ArgC; ++i) { 485 Expr *ArgExpr = E->getArg(i); 486 QualType ArgTy = ArgExpr->getType(); 487 if (!CGF.hasAggregateLLVMType(ArgTy)) { 488 // Scalar argument is passed by-value. 489 Args.push_back(CGF.EmitScalarExpr(ArgExpr)); 490 } else if (ArgTy->isAnyComplexType()) { 491 // Make a temporary alloca to pass the argument. 492 llvm::Value *DestMem = CGF.CreateTempAlloca(ConvertType(ArgTy)); 493 CGF.EmitComplexExprIntoAddr(ArgExpr, DestMem, false); 494 Args.push_back(DestMem); 495 } else { 496 llvm::Value *DestMem = CGF.CreateTempAlloca(ConvertType(ArgTy)); 497 CGF.EmitAggExpr(ArgExpr, DestMem, false); 498 Args.push_back(DestMem); 499 } 500 } 501 502 return Runtime->GenerateMessageSend(Builder, ConvertType(E->getType()), 503 Receiver, E->getSelector(), 504 &Args[0], Args.size()); 505} 506 507Value *ScalarExprEmitter::VisitObjCSelectorExpr(ObjCSelectorExpr *E) { 508 return Runtime->GetSelector(Builder, E->getSelector()); 509} 510 511Value *ScalarExprEmitter::VisitObjCProtocolExpr(ObjCProtocolExpr *E) { 512 // FIXME: This should pass the Decl not the name. 513 return Runtime->GenerateProtocolRef(Builder, E->getProtocol()); 514} 515 516Value *ScalarExprEmitter::VisitArraySubscriptExpr(ArraySubscriptExpr *E) { 517 // Emit subscript expressions in rvalue context's. For most cases, this just 518 // loads the lvalue formed by the subscript expr. However, we have to be 519 // careful, because the base of a vector subscript is occasionally an rvalue, 520 // so we can't get it as an lvalue. 521 if (!E->getBase()->getType()->isVectorType()) 522 return EmitLoadOfLValue(E); 523 524 // Handle the vector case. The base must be a vector, the index must be an 525 // integer value. 526 Value *Base = Visit(E->getBase()); 527 Value *Idx = Visit(E->getIdx()); 528 529 // FIXME: Convert Idx to i32 type. 530 return Builder.CreateExtractElement(Base, Idx, "vecext"); 531} 532 533/// VisitImplicitCastExpr - Implicit casts are the same as normal casts, but 534/// also handle things like function to pointer-to-function decay, and array to 535/// pointer decay. 536Value *ScalarExprEmitter::VisitImplicitCastExpr(const ImplicitCastExpr *E) { 537 const Expr *Op = E->getSubExpr(); 538 539 // If this is due to array->pointer conversion, emit the array expression as 540 // an l-value. 541 if (Op->getType()->isArrayType()) { 542 // FIXME: For now we assume that all source arrays map to LLVM arrays. This 543 // will not true when we add support for VLAs. 544 Value *V = EmitLValue(Op).getAddress(); // Bitfields can't be arrays. 545 546 assert(isa<llvm::PointerType>(V->getType()) && 547 isa<llvm::ArrayType>(cast<llvm::PointerType>(V->getType()) 548 ->getElementType()) && 549 "Doesn't support VLAs yet!"); 550 V = Builder.CreateStructGEP(V, 0, "arraydecay"); 551 552 // The resultant pointer type can be implicitly casted to other pointer 553 // types as well (e.g. void*) and can be implicitly converted to integer. 554 const llvm::Type *DestTy = ConvertType(E->getType()); 555 if (V->getType() != DestTy) { 556 if (isa<llvm::PointerType>(DestTy)) 557 V = Builder.CreateBitCast(V, DestTy, "ptrconv"); 558 else { 559 assert(isa<llvm::IntegerType>(DestTy) && "Unknown array decay"); 560 V = Builder.CreatePtrToInt(V, DestTy, "ptrconv"); 561 } 562 } 563 return V; 564 565 } else if (E->getType()->isReferenceType()) { 566 return EmitLValue(Op).getAddress(); 567 } 568 569 return EmitCastExpr(Op, E->getType()); 570} 571 572 573// VisitCastExpr - Emit code for an explicit or implicit cast. Implicit casts 574// have to handle a more broad range of conversions than explicit casts, as they 575// handle things like function to ptr-to-function decay etc. 576Value *ScalarExprEmitter::EmitCastExpr(const Expr *E, QualType DestTy) { 577 // Handle cases where the source is an non-complex type. 578 579 if (!CGF.hasAggregateLLVMType(E->getType())) { 580 Value *Src = Visit(const_cast<Expr*>(E)); 581 582 // Use EmitScalarConversion to perform the conversion. 583 return EmitScalarConversion(Src, E->getType(), DestTy); 584 } 585 586 if (E->getType()->isAnyComplexType()) { 587 // Handle cases where the source is a complex type. 588 return EmitComplexToScalarConversion(CGF.EmitComplexExpr(E), E->getType(), 589 DestTy); 590 } 591 592 // Okay, this is a cast from an aggregate. It must be a cast to void. Just 593 // evaluate the result and return. 594 CGF.EmitAggExpr(E, 0, false); 595 return 0; 596} 597 598Value *ScalarExprEmitter::VisitStmtExpr(const StmtExpr *E) { 599 return CGF.EmitCompoundStmt(*E->getSubStmt(), 600 !E->getType()->isVoidType()).getScalarVal(); 601} 602 603 604//===----------------------------------------------------------------------===// 605// Unary Operators 606//===----------------------------------------------------------------------===// 607 608Value *ScalarExprEmitter::VisitPrePostIncDec(const UnaryOperator *E, 609 bool isInc, bool isPre) { 610 LValue LV = EmitLValue(E->getSubExpr()); 611 // FIXME: Handle volatile! 612 Value *InVal = CGF.EmitLoadOfLValue(LV, // false 613 E->getSubExpr()->getType()).getScalarVal(); 614 615 int AmountVal = isInc ? 1 : -1; 616 617 Value *NextVal; 618 if (isa<llvm::PointerType>(InVal->getType())) { 619 // FIXME: This isn't right for VLAs. 620 NextVal = llvm::ConstantInt::get(llvm::Type::Int32Ty, AmountVal); 621 NextVal = Builder.CreateGEP(InVal, NextVal, "ptrincdec"); 622 } else { 623 // Add the inc/dec to the real part. 624 if (isa<llvm::IntegerType>(InVal->getType())) 625 NextVal = llvm::ConstantInt::get(InVal->getType(), AmountVal); 626 else if (InVal->getType() == llvm::Type::FloatTy) 627 NextVal = 628 llvm::ConstantFP::get(llvm::APFloat(static_cast<float>(AmountVal))); 629 else if (InVal->getType() == llvm::Type::DoubleTy) 630 NextVal = 631 llvm::ConstantFP::get(llvm::APFloat(static_cast<double>(AmountVal))); 632 else { 633 llvm::APFloat F(static_cast<float>(AmountVal)); 634 F.convert(CGF.Target.getLongDoubleFormat(), llvm::APFloat::rmTowardZero); 635 NextVal = llvm::ConstantFP::get(F); 636 } 637 NextVal = Builder.CreateAdd(InVal, NextVal, isInc ? "inc" : "dec"); 638 } 639 640 // Store the updated result through the lvalue. 641 CGF.EmitStoreThroughLValue(RValue::get(NextVal), LV, 642 E->getSubExpr()->getType()); 643 644 // If this is a postinc, return the value read from memory, otherwise use the 645 // updated value. 646 return isPre ? NextVal : InVal; 647} 648 649 650Value *ScalarExprEmitter::VisitUnaryMinus(const UnaryOperator *E) { 651 Value *Op = Visit(E->getSubExpr()); 652 return Builder.CreateNeg(Op, "neg"); 653} 654 655Value *ScalarExprEmitter::VisitUnaryNot(const UnaryOperator *E) { 656 Value *Op = Visit(E->getSubExpr()); 657 return Builder.CreateNot(Op, "neg"); 658} 659 660Value *ScalarExprEmitter::VisitUnaryLNot(const UnaryOperator *E) { 661 // Compare operand to zero. 662 Value *BoolVal = CGF.EvaluateExprAsBool(E->getSubExpr()); 663 664 // Invert value. 665 // TODO: Could dynamically modify easy computations here. For example, if 666 // the operand is an icmp ne, turn into icmp eq. 667 BoolVal = Builder.CreateNot(BoolVal, "lnot"); 668 669 // ZExt result to int. 670 return Builder.CreateZExt(BoolVal, CGF.LLVMIntTy, "lnot.ext"); 671} 672 673/// EmitSizeAlignOf - Return the size or alignment of the 'TypeToSize' type as 674/// an integer (RetType). 675Value *ScalarExprEmitter::EmitSizeAlignOf(QualType TypeToSize, 676 QualType RetType,bool isSizeOf){ 677 assert(RetType->isIntegerType() && "Result type must be an integer!"); 678 uint32_t ResultWidth = 679 static_cast<uint32_t>(CGF.getContext().getTypeSize(RetType)); 680 681 // sizeof(void) and __alignof__(void) = 1 as a gcc extension. Also 682 // for function types. 683 // FIXME: what is alignof a function type in gcc? 684 if (TypeToSize->isVoidType() || TypeToSize->isFunctionType()) 685 return llvm::ConstantInt::get(llvm::APInt(ResultWidth, 1)); 686 687 /// FIXME: This doesn't handle VLAs yet! 688 std::pair<uint64_t, unsigned> Info = CGF.getContext().getTypeInfo(TypeToSize); 689 690 uint64_t Val = isSizeOf ? Info.first : Info.second; 691 Val /= 8; // Return size in bytes, not bits. 692 693 return llvm::ConstantInt::get(llvm::APInt(ResultWidth, Val)); 694} 695 696Value *ScalarExprEmitter::VisitUnaryReal(const UnaryOperator *E) { 697 Expr *Op = E->getSubExpr(); 698 if (Op->getType()->isAnyComplexType()) 699 return CGF.EmitComplexExpr(Op).first; 700 return Visit(Op); 701} 702Value *ScalarExprEmitter::VisitUnaryImag(const UnaryOperator *E) { 703 Expr *Op = E->getSubExpr(); 704 if (Op->getType()->isAnyComplexType()) 705 return CGF.EmitComplexExpr(Op).second; 706 707 // __imag on a scalar returns zero. Emit it the subexpr to ensure side 708 // effects are evaluated. 709 CGF.EmitScalarExpr(Op); 710 return llvm::Constant::getNullValue(ConvertType(E->getType())); 711} 712 713Value *ScalarExprEmitter::VisitUnaryOffsetOf(const UnaryOperator *E) 714{ 715 int64_t Val = E->evaluateOffsetOf(CGF.getContext()); 716 717 assert(E->getType()->isIntegerType() && "Result type must be an integer!"); 718 719 uint32_t ResultWidth = 720 static_cast<uint32_t>(CGF.getContext().getTypeSize(E->getType())); 721 return llvm::ConstantInt::get(llvm::APInt(ResultWidth, Val)); 722} 723 724//===----------------------------------------------------------------------===// 725// Binary Operators 726//===----------------------------------------------------------------------===// 727 728BinOpInfo ScalarExprEmitter::EmitBinOps(const BinaryOperator *E) { 729 BinOpInfo Result; 730 Result.LHS = Visit(E->getLHS()); 731 Result.RHS = Visit(E->getRHS()); 732 Result.Ty = E->getType(); 733 Result.E = E; 734 return Result; 735} 736 737Value *ScalarExprEmitter::EmitCompoundAssign(const CompoundAssignOperator *E, 738 Value *(ScalarExprEmitter::*Func)(const BinOpInfo &)) { 739 QualType LHSTy = E->getLHS()->getType(), RHSTy = E->getRHS()->getType(); 740 741 BinOpInfo OpInfo; 742 743 // Load the LHS and RHS operands. 744 LValue LHSLV = EmitLValue(E->getLHS()); 745 OpInfo.LHS = EmitLoadOfLValue(LHSLV, LHSTy); 746 747 // Determine the computation type. If the RHS is complex, then this is one of 748 // the add/sub/mul/div operators. All of these operators can be computed in 749 // with just their real component even though the computation domain really is 750 // complex. 751 QualType ComputeType = E->getComputationType(); 752 753 // If the computation type is complex, then the RHS is complex. Emit the RHS. 754 if (const ComplexType *CT = ComputeType->getAsComplexType()) { 755 ComputeType = CT->getElementType(); 756 757 // Emit the RHS, only keeping the real component. 758 OpInfo.RHS = CGF.EmitComplexExpr(E->getRHS()).first; 759 RHSTy = RHSTy->getAsComplexType()->getElementType(); 760 } else { 761 // Otherwise the RHS is a simple scalar value. 762 OpInfo.RHS = Visit(E->getRHS()); 763 } 764 765 QualType LComputeTy, RComputeTy, ResultTy; 766 767 // Compound assignment does not contain enough information about all 768 // the types involved for pointer arithmetic cases. Figure it out 769 // here for now. 770 if (E->getLHS()->getType()->isPointerType()) { 771 // Pointer arithmetic cases: ptr +=,-= int and ptr -= ptr, 772 assert((E->getOpcode() == BinaryOperator::AddAssign || 773 E->getOpcode() == BinaryOperator::SubAssign) && 774 "Invalid compound assignment operator on pointer type."); 775 LComputeTy = E->getLHS()->getType(); 776 777 if (E->getRHS()->getType()->isPointerType()) { 778 // Degenerate case of (ptr -= ptr) allowed by GCC implicit cast 779 // extension, the conversion from the pointer difference back to 780 // the LHS type is handled at the end. 781 assert(E->getOpcode() == BinaryOperator::SubAssign && 782 "Invalid compound assignment operator on pointer type."); 783 RComputeTy = E->getLHS()->getType(); 784 ResultTy = CGF.getContext().getPointerDiffType(); 785 } else { 786 RComputeTy = E->getRHS()->getType(); 787 ResultTy = LComputeTy; 788 } 789 } else if (E->getRHS()->getType()->isPointerType()) { 790 // Degenerate case of (int += ptr) allowed by GCC implicit cast 791 // extension. 792 assert(E->getOpcode() == BinaryOperator::AddAssign && 793 "Invalid compound assignment operator on pointer type."); 794 LComputeTy = E->getLHS()->getType(); 795 RComputeTy = E->getRHS()->getType(); 796 ResultTy = RComputeTy; 797 } else { 798 LComputeTy = RComputeTy = ResultTy = ComputeType; 799 } 800 801 // Convert the LHS/RHS values to the computation type. 802 OpInfo.LHS = EmitScalarConversion(OpInfo.LHS, LHSTy, LComputeTy); 803 OpInfo.RHS = EmitScalarConversion(OpInfo.RHS, RHSTy, RComputeTy); 804 OpInfo.Ty = ResultTy; 805 OpInfo.E = E; 806 807 // Expand the binary operator. 808 Value *Result = (this->*Func)(OpInfo); 809 810 // Convert the result back to the LHS type. 811 Result = EmitScalarConversion(Result, ResultTy, LHSTy); 812 813 // Store the result value into the LHS lvalue. 814 CGF.EmitStoreThroughLValue(RValue::get(Result), LHSLV, LHSTy); 815 816 // For bitfields, we need the value in the bitfield 817 // FIXME: This adds an extra bitfield load 818 if (LHSLV.isBitfield()) 819 Result = EmitLoadOfLValue(LHSLV, LHSTy); 820 821 return Result; 822} 823 824 825Value *ScalarExprEmitter::EmitDiv(const BinOpInfo &Ops) { 826 if (Ops.LHS->getType()->isFPOrFPVector()) 827 return Builder.CreateFDiv(Ops.LHS, Ops.RHS, "div"); 828 else if (Ops.Ty->isUnsignedIntegerType()) 829 return Builder.CreateUDiv(Ops.LHS, Ops.RHS, "div"); 830 else 831 return Builder.CreateSDiv(Ops.LHS, Ops.RHS, "div"); 832} 833 834Value *ScalarExprEmitter::EmitRem(const BinOpInfo &Ops) { 835 // Rem in C can't be a floating point type: C99 6.5.5p2. 836 if (Ops.Ty->isUnsignedIntegerType()) 837 return Builder.CreateURem(Ops.LHS, Ops.RHS, "rem"); 838 else 839 return Builder.CreateSRem(Ops.LHS, Ops.RHS, "rem"); 840} 841 842 843Value *ScalarExprEmitter::EmitAdd(const BinOpInfo &Ops) { 844 if (!Ops.Ty->isPointerType()) 845 return Builder.CreateAdd(Ops.LHS, Ops.RHS, "add"); 846 847 // FIXME: What about a pointer to a VLA? 848 Value *Ptr, *Idx; 849 Expr *IdxExp; 850 if (isa<llvm::PointerType>(Ops.LHS->getType())) { // pointer + int 851 Ptr = Ops.LHS; 852 Idx = Ops.RHS; 853 IdxExp = Ops.E->getRHS(); 854 } else { // int + pointer 855 Ptr = Ops.RHS; 856 Idx = Ops.LHS; 857 IdxExp = Ops.E->getLHS(); 858 } 859 860 unsigned Width = cast<llvm::IntegerType>(Idx->getType())->getBitWidth(); 861 if (Width < CGF.LLVMPointerWidth) { 862 // Zero or sign extend the pointer value based on whether the index is 863 // signed or not. 864 const llvm::Type *IdxType = llvm::IntegerType::get(CGF.LLVMPointerWidth); 865 if (IdxExp->getType()->isSignedIntegerType()) 866 Idx = Builder.CreateSExt(Idx, IdxType, "idx.ext"); 867 else 868 Idx = Builder.CreateZExt(Idx, IdxType, "idx.ext"); 869 } 870 871 return Builder.CreateGEP(Ptr, Idx, "add.ptr"); 872} 873 874Value *ScalarExprEmitter::EmitSub(const BinOpInfo &Ops) { 875 if (!isa<llvm::PointerType>(Ops.LHS->getType())) 876 return Builder.CreateSub(Ops.LHS, Ops.RHS, "sub"); 877 878 if (!isa<llvm::PointerType>(Ops.RHS->getType())) { 879 // pointer - int 880 Value *Idx = Ops.RHS; 881 unsigned Width = cast<llvm::IntegerType>(Idx->getType())->getBitWidth(); 882 if (Width < CGF.LLVMPointerWidth) { 883 // Zero or sign extend the pointer value based on whether the index is 884 // signed or not. 885 const llvm::Type *IdxType = llvm::IntegerType::get(CGF.LLVMPointerWidth); 886 if (Ops.E->getRHS()->getType()->isSignedIntegerType()) 887 Idx = Builder.CreateSExt(Idx, IdxType, "idx.ext"); 888 else 889 Idx = Builder.CreateZExt(Idx, IdxType, "idx.ext"); 890 } 891 Idx = Builder.CreateNeg(Idx, "sub.ptr.neg"); 892 893 // FIXME: The pointer could point to a VLA. 894 // The GNU void* - int case is automatically handled here because 895 // our LLVM type for void* is i8*. 896 return Builder.CreateGEP(Ops.LHS, Idx, "sub.ptr"); 897 } else { 898 // pointer - pointer 899 Value *LHS = Ops.LHS; 900 Value *RHS = Ops.RHS; 901 902 const QualType LHSType = Ops.E->getLHS()->getType(); 903 const QualType LHSElementType = LHSType->getAsPointerType()->getPointeeType(); 904 uint64_t ElementSize; 905 906 // Handle GCC extension for pointer arithmetic on void* types. 907 if (LHSElementType->isVoidType()) { 908 ElementSize = 1; 909 } else { 910 ElementSize = CGF.getContext().getTypeSize(LHSElementType) / 8; 911 } 912 913 const llvm::Type *ResultType = ConvertType(Ops.Ty); 914 LHS = Builder.CreatePtrToInt(LHS, ResultType, "sub.ptr.lhs.cast"); 915 RHS = Builder.CreatePtrToInt(RHS, ResultType, "sub.ptr.rhs.cast"); 916 Value *BytesBetween = Builder.CreateSub(LHS, RHS, "sub.ptr.sub"); 917 918 // HACK: LLVM doesn't have an divide instruction that 'knows' there is no 919 // remainder. As such, we handle common power-of-two cases here to generate 920 // better code. See PR2247. 921 if (llvm::isPowerOf2_64(ElementSize)) { 922 Value *ShAmt = 923 llvm::ConstantInt::get(ResultType, llvm::Log2_64(ElementSize)); 924 return Builder.CreateAShr(BytesBetween, ShAmt, "sub.ptr.shr"); 925 } 926 927 // Otherwise, do a full sdiv. 928 Value *BytesPerElt = llvm::ConstantInt::get(ResultType, ElementSize); 929 return Builder.CreateSDiv(BytesBetween, BytesPerElt, "sub.ptr.div"); 930 } 931} 932 933Value *ScalarExprEmitter::EmitShl(const BinOpInfo &Ops) { 934 // LLVM requires the LHS and RHS to be the same type: promote or truncate the 935 // RHS to the same size as the LHS. 936 Value *RHS = Ops.RHS; 937 if (Ops.LHS->getType() != RHS->getType()) 938 RHS = Builder.CreateIntCast(RHS, Ops.LHS->getType(), false, "sh_prom"); 939 940 return Builder.CreateShl(Ops.LHS, RHS, "shl"); 941} 942 943Value *ScalarExprEmitter::EmitShr(const BinOpInfo &Ops) { 944 // LLVM requires the LHS and RHS to be the same type: promote or truncate the 945 // RHS to the same size as the LHS. 946 Value *RHS = Ops.RHS; 947 if (Ops.LHS->getType() != RHS->getType()) 948 RHS = Builder.CreateIntCast(RHS, Ops.LHS->getType(), false, "sh_prom"); 949 950 if (Ops.Ty->isUnsignedIntegerType()) 951 return Builder.CreateLShr(Ops.LHS, RHS, "shr"); 952 return Builder.CreateAShr(Ops.LHS, RHS, "shr"); 953} 954 955Value *ScalarExprEmitter::EmitCompare(const BinaryOperator *E,unsigned UICmpOpc, 956 unsigned SICmpOpc, unsigned FCmpOpc) { 957 Value *Result; 958 QualType LHSTy = E->getLHS()->getType(); 959 if (!LHSTy->isAnyComplexType() && !LHSTy->isVectorType()) { 960 Value *LHS = Visit(E->getLHS()); 961 Value *RHS = Visit(E->getRHS()); 962 963 if (LHS->getType()->isFloatingPoint()) { 964 Result = Builder.CreateFCmp((llvm::CmpInst::Predicate)FCmpOpc, 965 LHS, RHS, "cmp"); 966 } else if (LHSTy->isSignedIntegerType()) { 967 Result = Builder.CreateICmp((llvm::ICmpInst::Predicate)SICmpOpc, 968 LHS, RHS, "cmp"); 969 } else { 970 // Unsigned integers and pointers. 971 Result = Builder.CreateICmp((llvm::ICmpInst::Predicate)UICmpOpc, 972 LHS, RHS, "cmp"); 973 } 974 } else if (LHSTy->isVectorType()) { 975 Value *LHS = Visit(E->getLHS()); 976 Value *RHS = Visit(E->getRHS()); 977 978 if (LHS->getType()->isFPOrFPVector()) { 979 Result = Builder.CreateVFCmp((llvm::CmpInst::Predicate)FCmpOpc, 980 LHS, RHS, "cmp"); 981 } else if (LHSTy->isUnsignedIntegerType()) { 982 Result = Builder.CreateVICmp((llvm::CmpInst::Predicate)UICmpOpc, 983 LHS, RHS, "cmp"); 984 } else { 985 // Signed integers and pointers. 986 Result = Builder.CreateVICmp((llvm::CmpInst::Predicate)SICmpOpc, 987 LHS, RHS, "cmp"); 988 } 989 return Result; 990 } else { 991 // Complex Comparison: can only be an equality comparison. 992 CodeGenFunction::ComplexPairTy LHS = CGF.EmitComplexExpr(E->getLHS()); 993 CodeGenFunction::ComplexPairTy RHS = CGF.EmitComplexExpr(E->getRHS()); 994 995 QualType CETy = LHSTy->getAsComplexType()->getElementType(); 996 997 Value *ResultR, *ResultI; 998 if (CETy->isRealFloatingType()) { 999 ResultR = Builder.CreateFCmp((llvm::FCmpInst::Predicate)FCmpOpc, 1000 LHS.first, RHS.first, "cmp.r"); 1001 ResultI = Builder.CreateFCmp((llvm::FCmpInst::Predicate)FCmpOpc, 1002 LHS.second, RHS.second, "cmp.i"); 1003 } else { 1004 // Complex comparisons can only be equality comparisons. As such, signed 1005 // and unsigned opcodes are the same. 1006 ResultR = Builder.CreateICmp((llvm::ICmpInst::Predicate)UICmpOpc, 1007 LHS.first, RHS.first, "cmp.r"); 1008 ResultI = Builder.CreateICmp((llvm::ICmpInst::Predicate)UICmpOpc, 1009 LHS.second, RHS.second, "cmp.i"); 1010 } 1011 1012 if (E->getOpcode() == BinaryOperator::EQ) { 1013 Result = Builder.CreateAnd(ResultR, ResultI, "and.ri"); 1014 } else { 1015 assert(E->getOpcode() == BinaryOperator::NE && 1016 "Complex comparison other than == or != ?"); 1017 Result = Builder.CreateOr(ResultR, ResultI, "or.ri"); 1018 } 1019 } 1020 1021 // ZExt result to int. 1022 return Builder.CreateZExt(Result, CGF.LLVMIntTy, "cmp.ext"); 1023} 1024 1025Value *ScalarExprEmitter::VisitBinAssign(const BinaryOperator *E) { 1026 LValue LHS = EmitLValue(E->getLHS()); 1027 Value *RHS = Visit(E->getRHS()); 1028 1029 // Store the value into the LHS. 1030 // FIXME: Volatility! 1031 CGF.EmitStoreThroughLValue(RValue::get(RHS), LHS, E->getType()); 1032 1033 // For bitfields, we need the value in the bitfield 1034 // FIXME: This adds an extra bitfield load 1035 if (LHS.isBitfield()) 1036 return EmitLoadOfLValue(LHS, E->getLHS()->getType()); 1037 // Return the RHS. 1038 return RHS; 1039} 1040 1041Value *ScalarExprEmitter::VisitBinLAnd(const BinaryOperator *E) { 1042 Value *LHSCond = CGF.EvaluateExprAsBool(E->getLHS()); 1043 1044 llvm::BasicBlock *ContBlock = llvm::BasicBlock::Create("land_cont"); 1045 llvm::BasicBlock *RHSBlock = llvm::BasicBlock::Create("land_rhs"); 1046 1047 llvm::BasicBlock *OrigBlock = Builder.GetInsertBlock(); 1048 Builder.CreateCondBr(LHSCond, RHSBlock, ContBlock); 1049 1050 CGF.EmitBlock(RHSBlock); 1051 Value *RHSCond = CGF.EvaluateExprAsBool(E->getRHS()); 1052 1053 // Reaquire the RHS block, as there may be subblocks inserted. 1054 RHSBlock = Builder.GetInsertBlock(); 1055 CGF.EmitBlock(ContBlock); 1056 1057 // Create a PHI node. If we just evaluted the LHS condition, the result is 1058 // false. If we evaluated both, the result is the RHS condition. 1059 llvm::PHINode *PN = Builder.CreatePHI(llvm::Type::Int1Ty, "land"); 1060 PN->reserveOperandSpace(2); 1061 PN->addIncoming(llvm::ConstantInt::getFalse(), OrigBlock); 1062 PN->addIncoming(RHSCond, RHSBlock); 1063 1064 // ZExt result to int. 1065 return Builder.CreateZExt(PN, CGF.LLVMIntTy, "land.ext"); 1066} 1067 1068Value *ScalarExprEmitter::VisitBinLOr(const BinaryOperator *E) { 1069 Value *LHSCond = CGF.EvaluateExprAsBool(E->getLHS()); 1070 1071 llvm::BasicBlock *ContBlock = llvm::BasicBlock::Create("lor_cont"); 1072 llvm::BasicBlock *RHSBlock = llvm::BasicBlock::Create("lor_rhs"); 1073 1074 llvm::BasicBlock *OrigBlock = Builder.GetInsertBlock(); 1075 Builder.CreateCondBr(LHSCond, ContBlock, RHSBlock); 1076 1077 CGF.EmitBlock(RHSBlock); 1078 Value *RHSCond = CGF.EvaluateExprAsBool(E->getRHS()); 1079 1080 // Reaquire the RHS block, as there may be subblocks inserted. 1081 RHSBlock = Builder.GetInsertBlock(); 1082 CGF.EmitBlock(ContBlock); 1083 1084 // Create a PHI node. If we just evaluted the LHS condition, the result is 1085 // true. If we evaluated both, the result is the RHS condition. 1086 llvm::PHINode *PN = Builder.CreatePHI(llvm::Type::Int1Ty, "lor"); 1087 PN->reserveOperandSpace(2); 1088 PN->addIncoming(llvm::ConstantInt::getTrue(), OrigBlock); 1089 PN->addIncoming(RHSCond, RHSBlock); 1090 1091 // ZExt result to int. 1092 return Builder.CreateZExt(PN, CGF.LLVMIntTy, "lor.ext"); 1093} 1094 1095Value *ScalarExprEmitter::VisitBinComma(const BinaryOperator *E) { 1096 CGF.EmitStmt(E->getLHS()); 1097 return Visit(E->getRHS()); 1098} 1099 1100//===----------------------------------------------------------------------===// 1101// Other Operators 1102//===----------------------------------------------------------------------===// 1103 1104Value *ScalarExprEmitter:: 1105VisitConditionalOperator(const ConditionalOperator *E) { 1106 llvm::BasicBlock *LHSBlock = llvm::BasicBlock::Create("cond.?"); 1107 llvm::BasicBlock *RHSBlock = llvm::BasicBlock::Create("cond.:"); 1108 llvm::BasicBlock *ContBlock = llvm::BasicBlock::Create("cond.cont"); 1109 1110 // Evaluate the conditional, then convert it to bool. We do this explicitly 1111 // because we need the unconverted value if this is a GNU ?: expression with 1112 // missing middle value. 1113 Value *CondVal = CGF.EmitScalarExpr(E->getCond()); 1114 Value *CondBoolVal =CGF.EmitScalarConversion(CondVal, E->getCond()->getType(), 1115 CGF.getContext().BoolTy); 1116 Builder.CreateCondBr(CondBoolVal, LHSBlock, RHSBlock); 1117 1118 CGF.EmitBlock(LHSBlock); 1119 1120 // Handle the GNU extension for missing LHS. 1121 Value *LHS; 1122 if (E->getLHS()) 1123 LHS = Visit(E->getLHS()); 1124 else // Perform promotions, to handle cases like "short ?: int" 1125 LHS = EmitScalarConversion(CondVal, E->getCond()->getType(), E->getType()); 1126 1127 Builder.CreateBr(ContBlock); 1128 LHSBlock = Builder.GetInsertBlock(); 1129 1130 CGF.EmitBlock(RHSBlock); 1131 1132 Value *RHS = Visit(E->getRHS()); 1133 Builder.CreateBr(ContBlock); 1134 RHSBlock = Builder.GetInsertBlock(); 1135 1136 CGF.EmitBlock(ContBlock); 1137 1138 if (!LHS || !RHS) { 1139 assert(E->getType()->isVoidType() && "Non-void value should have a value"); 1140 return 0; 1141 } 1142 1143 // Create a PHI node for the real part. 1144 llvm::PHINode *PN = Builder.CreatePHI(LHS->getType(), "cond"); 1145 PN->reserveOperandSpace(2); 1146 PN->addIncoming(LHS, LHSBlock); 1147 PN->addIncoming(RHS, RHSBlock); 1148 return PN; 1149} 1150 1151Value *ScalarExprEmitter::VisitChooseExpr(ChooseExpr *E) { 1152 // Emit the LHS or RHS as appropriate. 1153 return 1154 Visit(E->isConditionTrue(CGF.getContext()) ? E->getLHS() : E->getRHS()); 1155} 1156 1157Value *ScalarExprEmitter::VisitOverloadExpr(OverloadExpr *E) { 1158 return CGF.EmitCallExpr(E->getFn(), E->arg_begin(), 1159 E->arg_end(CGF.getContext())).getScalarVal(); 1160} 1161 1162Value *ScalarExprEmitter::VisitVAArgExpr(VAArgExpr *VE) { 1163 llvm::Value *ArgValue = EmitLValue(VE->getSubExpr()).getAddress(); 1164 1165 llvm::Value *V = Builder.CreateVAArg(ArgValue, ConvertType(VE->getType())); 1166 return V; 1167} 1168 1169Value *ScalarExprEmitter::VisitObjCEncodeExpr(const ObjCEncodeExpr *E) { 1170 std::string str; 1171 llvm::SmallVector<const RecordType *, 8> EncodingRecordTypes; 1172 CGF.getContext().getObjCEncodingForType(E->getEncodedType(), str, 1173 EncodingRecordTypes); 1174 1175 llvm::Constant *C = llvm::ConstantArray::get(str); 1176 C = new llvm::GlobalVariable(C->getType(), true, 1177 llvm::GlobalValue::InternalLinkage, 1178 C, ".str", &CGF.CGM.getModule()); 1179 llvm::Constant *Zero = llvm::Constant::getNullValue(llvm::Type::Int32Ty); 1180 llvm::Constant *Zeros[] = { Zero, Zero }; 1181 C = llvm::ConstantExpr::getGetElementPtr(C, Zeros, 2); 1182 1183 return C; 1184} 1185 1186//===----------------------------------------------------------------------===// 1187// Entry Point into this File 1188//===----------------------------------------------------------------------===// 1189 1190/// EmitComplexExpr - Emit the computation of the specified expression of 1191/// complex type, ignoring the result. 1192Value *CodeGenFunction::EmitScalarExpr(const Expr *E) { 1193 assert(E && !hasAggregateLLVMType(E->getType()) && 1194 "Invalid scalar expression to emit"); 1195 1196 return ScalarExprEmitter(*this).Visit(const_cast<Expr*>(E)); 1197} 1198 1199/// EmitScalarConversion - Emit a conversion from the specified type to the 1200/// specified destination type, both of which are LLVM scalar types. 1201Value *CodeGenFunction::EmitScalarConversion(Value *Src, QualType SrcTy, 1202 QualType DstTy) { 1203 assert(!hasAggregateLLVMType(SrcTy) && !hasAggregateLLVMType(DstTy) && 1204 "Invalid scalar expression to emit"); 1205 return ScalarExprEmitter(*this).EmitScalarConversion(Src, SrcTy, DstTy); 1206} 1207 1208/// EmitComplexToScalarConversion - Emit a conversion from the specified 1209/// complex type to the specified destination type, where the destination 1210/// type is an LLVM scalar type. 1211Value *CodeGenFunction::EmitComplexToScalarConversion(ComplexPairTy Src, 1212 QualType SrcTy, 1213 QualType DstTy) { 1214 assert(SrcTy->isAnyComplexType() && !hasAggregateLLVMType(DstTy) && 1215 "Invalid complex -> scalar conversion"); 1216 return ScalarExprEmitter(*this).EmitComplexToScalarConversion(Src, SrcTy, 1217 DstTy); 1218} 1219 1220Value *CodeGenFunction::EmitShuffleVector(Value* V1, Value *V2, ...) { 1221 assert(V1->getType() == V2->getType() && 1222 "Vector operands must be of the same type"); 1223 unsigned NumElements = 1224 cast<llvm::VectorType>(V1->getType())->getNumElements(); 1225 1226 va_list va; 1227 va_start(va, V2); 1228 1229 llvm::SmallVector<llvm::Constant*, 16> Args; 1230 for (unsigned i = 0; i < NumElements; i++) { 1231 int n = va_arg(va, int); 1232 assert(n >= 0 && n < (int)NumElements * 2 && 1233 "Vector shuffle index out of bounds!"); 1234 Args.push_back(llvm::ConstantInt::get(llvm::Type::Int32Ty, n)); 1235 } 1236 1237 const char *Name = va_arg(va, const char *); 1238 va_end(va); 1239 1240 llvm::Constant *Mask = llvm::ConstantVector::get(&Args[0], NumElements); 1241 1242 return Builder.CreateShuffleVector(V1, V2, Mask, Name); 1243} 1244 1245llvm::Value *CodeGenFunction::EmitVector(llvm::Value * const *Vals, 1246 unsigned NumVals, bool isSplat) { 1247 llvm::Value *Vec 1248 = llvm::UndefValue::get(llvm::VectorType::get(Vals[0]->getType(), NumVals)); 1249 1250 for (unsigned i = 0, e = NumVals; i != e; ++i) { 1251 llvm::Value *Val = isSplat ? Vals[0] : Vals[i]; 1252 llvm::Value *Idx = llvm::ConstantInt::get(llvm::Type::Int32Ty, i); 1253 Vec = Builder.CreateInsertElement(Vec, Val, Idx, "tmp"); 1254 } 1255 1256 return Vec; 1257} 1258