CGExprScalar.cpp revision 22711185f2368bea6325504b58cac021857eb0d7
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/Support/Compiler.h" 25#include <cstdarg> 26 27using namespace clang; 28using namespace CodeGen; 29using llvm::Value; 30 31//===----------------------------------------------------------------------===// 32// Scalar Expression Emitter 33//===----------------------------------------------------------------------===// 34 35struct BinOpInfo { 36 Value *LHS; 37 Value *RHS; 38 QualType Ty; // Computation Type. 39 const BinaryOperator *E; 40}; 41 42namespace { 43class VISIBILITY_HIDDEN ScalarExprEmitter 44 : public StmtVisitor<ScalarExprEmitter, Value*> { 45 CodeGenFunction &CGF; 46 llvm::IRBuilder<> &Builder; 47 CGObjCRuntime *Runtime; 48 49public: 50 51 ScalarExprEmitter(CodeGenFunction &cgf) : CGF(cgf), 52 Builder(CGF.Builder), 53 Runtime(0) { 54 if (CGF.CGM.hasObjCRuntime()) 55 Runtime = &CGF.CGM.getObjCRuntime(); 56 } 57 58 //===--------------------------------------------------------------------===// 59 // Utilities 60 //===--------------------------------------------------------------------===// 61 62 const llvm::Type *ConvertType(QualType T) { return CGF.ConvertType(T); } 63 LValue EmitLValue(const Expr *E) { return CGF.EmitLValue(E); } 64 65 Value *EmitLoadOfLValue(LValue LV, QualType T) { 66 return CGF.EmitLoadOfLValue(LV, T).getScalarVal(); 67 } 68 69 /// EmitLoadOfLValue - Given an expression with complex type that represents a 70 /// value l-value, this method emits the address of the l-value, then loads 71 /// and returns the result. 72 Value *EmitLoadOfLValue(const Expr *E) { 73 // FIXME: Volatile 74 return EmitLoadOfLValue(EmitLValue(E), E->getType()); 75 } 76 77 /// EmitConversionToBool - Convert the specified expression value to a 78 /// boolean (i1) truth value. This is equivalent to "Val != 0". 79 Value *EmitConversionToBool(Value *Src, QualType DstTy); 80 81 /// EmitScalarConversion - Emit a conversion from the specified type to the 82 /// specified destination type, both of which are LLVM scalar types. 83 Value *EmitScalarConversion(Value *Src, QualType SrcTy, QualType DstTy); 84 85 /// EmitComplexToScalarConversion - Emit a conversion from the specified 86 /// complex type to the specified destination type, where the destination 87 /// type is an LLVM scalar type. 88 Value *EmitComplexToScalarConversion(CodeGenFunction::ComplexPairTy Src, 89 QualType SrcTy, QualType DstTy); 90 91 //===--------------------------------------------------------------------===// 92 // Visitor Methods 93 //===--------------------------------------------------------------------===// 94 95 Value *VisitStmt(Stmt *S) { 96 S->dump(CGF.getContext().getSourceManager()); 97 assert(0 && "Stmt can't have complex result type!"); 98 return 0; 99 } 100 Value *VisitExpr(Expr *S); 101 Value *VisitParenExpr(ParenExpr *PE) { return Visit(PE->getSubExpr()); } 102 103 // Leaves. 104 Value *VisitIntegerLiteral(const IntegerLiteral *E) { 105 return llvm::ConstantInt::get(E->getValue()); 106 } 107 Value *VisitFloatingLiteral(const FloatingLiteral *E) { 108 return llvm::ConstantFP::get(E->getValue()); 109 } 110 Value *VisitCharacterLiteral(const CharacterLiteral *E) { 111 return llvm::ConstantInt::get(ConvertType(E->getType()), E->getValue()); 112 } 113 Value *VisitCXXBoolLiteralExpr(const CXXBoolLiteralExpr *E) { 114 return llvm::ConstantInt::get(ConvertType(E->getType()), E->getValue()); 115 } 116 Value *VisitTypesCompatibleExpr(const TypesCompatibleExpr *E) { 117 return llvm::ConstantInt::get(ConvertType(E->getType()), 118 CGF.getContext().typesAreCompatible( 119 E->getArgType1(), E->getArgType2())); 120 } 121 Value *VisitSizeOfAlignOfTypeExpr(const SizeOfAlignOfTypeExpr *E) { 122 return EmitSizeAlignOf(E->getArgumentType(), E->getType(), E->isSizeOf()); 123 } 124 Value *VisitAddrLabelExpr(const AddrLabelExpr *E) { 125 Value *V = llvm::ConstantInt::get(llvm::Type::Int32Ty, 126 CGF.GetIDForAddrOfLabel(E->getLabel())); 127 return Builder.CreateIntToPtr(V, 128 llvm::PointerType::getUnqual(llvm::Type::Int8Ty)); 129 } 130 131 // l-values. 132 Value *VisitDeclRefExpr(DeclRefExpr *E) { 133 if (const EnumConstantDecl *EC = dyn_cast<EnumConstantDecl>(E->getDecl())) 134 return llvm::ConstantInt::get(EC->getInitVal()); 135 return EmitLoadOfLValue(E); 136 } 137 Value *VisitObjCMessageExpr(ObjCMessageExpr *E); 138 Value *VisitObjCSelectorExpr(ObjCSelectorExpr *E); 139 Value *VisitObjCProtocolExpr(ObjCProtocolExpr *E); 140 Value *VisitObjCIvarRefExpr(ObjCIvarRefExpr *E) { return EmitLoadOfLValue(E);} 141 Value *VisitArraySubscriptExpr(ArraySubscriptExpr *E); 142 Value *VisitShuffleVectorExpr(ShuffleVectorExpr *E); 143 Value *VisitMemberExpr(Expr *E) { return EmitLoadOfLValue(E); } 144 Value *VisitExtVectorElementExpr(Expr *E) { return EmitLoadOfLValue(E); } 145 Value *VisitCompoundLiteralExpr(CompoundLiteralExpr *E) { return EmitLoadOfLValue(E); } 146 Value *VisitStringLiteral(Expr *E) { return EmitLValue(E).getAddress(); } 147 Value *VisitPredefinedExpr(Expr *E) { return EmitLValue(E).getAddress(); } 148 149 Value *VisitInitListExpr(InitListExpr *E) { 150 unsigned NumInitElements = E->getNumInits(); 151 152 const llvm::VectorType *VType = 153 dyn_cast<llvm::VectorType>(ConvertType(E->getType())); 154 155 // We have a scalar in braces. Just use the first element. 156 if (!VType) 157 return Visit(E->getInit(0)); 158 159 unsigned NumVectorElements = VType->getNumElements(); 160 const llvm::Type *ElementType = VType->getElementType(); 161 162 // Emit individual vector element stores. 163 llvm::Value *V = llvm::UndefValue::get(VType); 164 165 // Emit initializers 166 unsigned i; 167 for (i = 0; i < NumInitElements; ++i) { 168 Value *NewV = Visit(E->getInit(i)); 169 Value *Idx = llvm::ConstantInt::get(llvm::Type::Int32Ty, i); 170 V = Builder.CreateInsertElement(V, NewV, Idx); 171 } 172 173 // Emit remaining default initializers 174 for (/* Do not initialize i*/; i < NumVectorElements; ++i) { 175 Value *Idx = llvm::ConstantInt::get(llvm::Type::Int32Ty, i); 176 llvm::Value *NewV = llvm::Constant::getNullValue(ElementType); 177 V = Builder.CreateInsertElement(V, NewV, Idx); 178 } 179 180 return V; 181 } 182 183 Value *VisitImplicitCastExpr(const ImplicitCastExpr *E); 184 Value *VisitCastExpr(const CastExpr *E) { 185 return EmitCastExpr(E->getSubExpr(), E->getType()); 186 } 187 Value *EmitCastExpr(const Expr *E, QualType T); 188 189 Value *VisitCallExpr(const CallExpr *E) { 190 return CGF.EmitCallExpr(E).getScalarVal(); 191 } 192 193 Value *VisitStmtExpr(const StmtExpr *E); 194 195 // Unary Operators. 196 Value *VisitPrePostIncDec(const UnaryOperator *E, bool isInc, bool isPre); 197 Value *VisitUnaryPostDec(const UnaryOperator *E) { 198 return VisitPrePostIncDec(E, false, false); 199 } 200 Value *VisitUnaryPostInc(const UnaryOperator *E) { 201 return VisitPrePostIncDec(E, true, false); 202 } 203 Value *VisitUnaryPreDec(const UnaryOperator *E) { 204 return VisitPrePostIncDec(E, false, true); 205 } 206 Value *VisitUnaryPreInc(const UnaryOperator *E) { 207 return VisitPrePostIncDec(E, true, true); 208 } 209 Value *VisitUnaryAddrOf(const UnaryOperator *E) { 210 return EmitLValue(E->getSubExpr()).getAddress(); 211 } 212 Value *VisitUnaryDeref(const Expr *E) { return EmitLoadOfLValue(E); } 213 Value *VisitUnaryPlus(const UnaryOperator *E) { 214 return Visit(E->getSubExpr()); 215 } 216 Value *VisitUnaryMinus (const UnaryOperator *E); 217 Value *VisitUnaryNot (const UnaryOperator *E); 218 Value *VisitUnaryLNot (const UnaryOperator *E); 219 Value *VisitUnarySizeOf (const UnaryOperator *E) { 220 return EmitSizeAlignOf(E->getSubExpr()->getType(), E->getType(), true); 221 } 222 Value *VisitUnaryAlignOf (const UnaryOperator *E) { 223 return EmitSizeAlignOf(E->getSubExpr()->getType(), E->getType(), false); 224 } 225 Value *EmitSizeAlignOf(QualType TypeToSize, QualType RetType, 226 bool isSizeOf); 227 Value *VisitUnaryReal (const UnaryOperator *E); 228 Value *VisitUnaryImag (const UnaryOperator *E); 229 Value *VisitUnaryExtension(const UnaryOperator *E) { 230 return Visit(E->getSubExpr()); 231 } 232 Value *VisitUnaryOffsetOf(const UnaryOperator *E); 233 Value *VisitCXXDefaultArgExpr(CXXDefaultArgExpr *DAE) { 234 return Visit(DAE->getExpr()); 235 } 236 237 // Binary Operators. 238 Value *EmitMul(const BinOpInfo &Ops) { 239 return Builder.CreateMul(Ops.LHS, Ops.RHS, "mul"); 240 } 241 Value *EmitDiv(const BinOpInfo &Ops); 242 Value *EmitRem(const BinOpInfo &Ops); 243 Value *EmitAdd(const BinOpInfo &Ops); 244 Value *EmitSub(const BinOpInfo &Ops); 245 Value *EmitShl(const BinOpInfo &Ops); 246 Value *EmitShr(const BinOpInfo &Ops); 247 Value *EmitAnd(const BinOpInfo &Ops) { 248 return Builder.CreateAnd(Ops.LHS, Ops.RHS, "and"); 249 } 250 Value *EmitXor(const BinOpInfo &Ops) { 251 return Builder.CreateXor(Ops.LHS, Ops.RHS, "xor"); 252 } 253 Value *EmitOr (const BinOpInfo &Ops) { 254 return Builder.CreateOr(Ops.LHS, Ops.RHS, "or"); 255 } 256 257 BinOpInfo EmitBinOps(const BinaryOperator *E); 258 Value *EmitCompoundAssign(const CompoundAssignOperator *E, 259 Value *(ScalarExprEmitter::*F)(const BinOpInfo &)); 260 261 // Binary operators and binary compound assignment operators. 262#define HANDLEBINOP(OP) \ 263 Value *VisitBin ## OP(const BinaryOperator *E) { \ 264 return Emit ## OP(EmitBinOps(E)); \ 265 } \ 266 Value *VisitBin ## OP ## Assign(const CompoundAssignOperator *E) { \ 267 return EmitCompoundAssign(E, &ScalarExprEmitter::Emit ## OP); \ 268 } 269 HANDLEBINOP(Mul); 270 HANDLEBINOP(Div); 271 HANDLEBINOP(Rem); 272 HANDLEBINOP(Add); 273 HANDLEBINOP(Sub); 274 HANDLEBINOP(Shl); 275 HANDLEBINOP(Shr); 276 HANDLEBINOP(And); 277 HANDLEBINOP(Xor); 278 HANDLEBINOP(Or); 279#undef HANDLEBINOP 280 281 // Comparisons. 282 Value *EmitCompare(const BinaryOperator *E, unsigned UICmpOpc, 283 unsigned SICmpOpc, unsigned FCmpOpc); 284#define VISITCOMP(CODE, UI, SI, FP) \ 285 Value *VisitBin##CODE(const BinaryOperator *E) { \ 286 return EmitCompare(E, llvm::ICmpInst::UI, llvm::ICmpInst::SI, \ 287 llvm::FCmpInst::FP); } 288 VISITCOMP(LT, ICMP_ULT, ICMP_SLT, FCMP_OLT); 289 VISITCOMP(GT, ICMP_UGT, ICMP_SGT, FCMP_OGT); 290 VISITCOMP(LE, ICMP_ULE, ICMP_SLE, FCMP_OLE); 291 VISITCOMP(GE, ICMP_UGE, ICMP_SGE, FCMP_OGE); 292 VISITCOMP(EQ, ICMP_EQ , ICMP_EQ , FCMP_OEQ); 293 VISITCOMP(NE, ICMP_NE , ICMP_NE , FCMP_UNE); 294#undef VISITCOMP 295 296 Value *VisitBinAssign (const BinaryOperator *E); 297 298 Value *VisitBinLAnd (const BinaryOperator *E); 299 Value *VisitBinLOr (const BinaryOperator *E); 300 Value *VisitBinComma (const BinaryOperator *E); 301 302 // Other Operators. 303 Value *VisitConditionalOperator(const ConditionalOperator *CO); 304 Value *VisitChooseExpr(ChooseExpr *CE); 305 Value *VisitOverloadExpr(OverloadExpr *OE); 306 Value *VisitVAArgExpr(VAArgExpr *VE); 307 Value *VisitObjCStringLiteral(const ObjCStringLiteral *E) { 308 return CGF.EmitObjCStringLiteral(E); 309 } 310 Value *VisitObjCEncodeExpr(const ObjCEncodeExpr *E); 311}; 312} // end anonymous namespace. 313 314//===----------------------------------------------------------------------===// 315// Utilities 316//===----------------------------------------------------------------------===// 317 318/// EmitConversionToBool - Convert the specified expression value to a 319/// boolean (i1) truth value. This is equivalent to "Val != 0". 320Value *ScalarExprEmitter::EmitConversionToBool(Value *Src, QualType SrcType) { 321 assert(SrcType->isCanonical() && "EmitScalarConversion strips typedefs"); 322 323 if (SrcType->isRealFloatingType()) { 324 // Compare against 0.0 for fp scalars. 325 llvm::Value *Zero = llvm::Constant::getNullValue(Src->getType()); 326 return Builder.CreateFCmpUNE(Src, Zero, "tobool"); 327 } 328 329 assert((SrcType->isIntegerType() || SrcType->isPointerType()) && 330 "Unknown scalar type to convert"); 331 332 // Because of the type rules of C, we often end up computing a logical value, 333 // then zero extending it to int, then wanting it as a logical value again. 334 // Optimize this common case. 335 if (llvm::ZExtInst *ZI = dyn_cast<llvm::ZExtInst>(Src)) { 336 if (ZI->getOperand(0)->getType() == llvm::Type::Int1Ty) { 337 Value *Result = ZI->getOperand(0); 338 // If there aren't any more uses, zap the instruction to save space. 339 // Note that there can be more uses, for example if this 340 // is the result of an assignment. 341 if (ZI->use_empty()) 342 ZI->eraseFromParent(); 343 return Result; 344 } 345 } 346 347 // Compare against an integer or pointer null. 348 llvm::Value *Zero = llvm::Constant::getNullValue(Src->getType()); 349 return Builder.CreateICmpNE(Src, Zero, "tobool"); 350} 351 352/// EmitScalarConversion - Emit a conversion from the specified type to the 353/// specified destination type, both of which are LLVM scalar types. 354Value *ScalarExprEmitter::EmitScalarConversion(Value *Src, QualType SrcType, 355 QualType DstType) { 356 SrcType = CGF.getContext().getCanonicalType(SrcType); 357 DstType = CGF.getContext().getCanonicalType(DstType); 358 if (SrcType == DstType) return Src; 359 360 if (DstType->isVoidType()) return 0; 361 362 // Handle conversions to bool first, they are special: comparisons against 0. 363 if (DstType->isBooleanType()) 364 return EmitConversionToBool(Src, SrcType); 365 366 const llvm::Type *DstTy = ConvertType(DstType); 367 368 // Ignore conversions like int -> uint. 369 if (Src->getType() == DstTy) 370 return Src; 371 372 // Handle pointer conversions next: pointers can only be converted to/from 373 // other pointers and integers. 374 if (isa<PointerType>(DstType)) { 375 // The source value may be an integer, or a pointer. 376 if (isa<llvm::PointerType>(Src->getType())) 377 return Builder.CreateBitCast(Src, DstTy, "conv"); 378 assert(SrcType->isIntegerType() && "Not ptr->ptr or int->ptr conversion?"); 379 return Builder.CreateIntToPtr(Src, DstTy, "conv"); 380 } 381 382 if (isa<PointerType>(SrcType)) { 383 // Must be an ptr to int cast. 384 assert(isa<llvm::IntegerType>(DstTy) && "not ptr->int?"); 385 return Builder.CreatePtrToInt(Src, DstTy, "conv"); 386 } 387 388 // A scalar can be splatted to an extended vector of the same element type 389 if (DstType->isExtVectorType() && !isa<VectorType>(SrcType) && 390 cast<llvm::VectorType>(DstTy)->getElementType() == Src->getType()) 391 return CGF.EmitVector(&Src, DstType->getAsVectorType()->getNumElements(), 392 true); 393 394 // Allow bitcast from vector to integer/fp of the same size. 395 if (isa<llvm::VectorType>(Src->getType()) || 396 isa<llvm::VectorType>(DstTy)) 397 return Builder.CreateBitCast(Src, DstTy, "conv"); 398 399 // Finally, we have the arithmetic types: real int/float. 400 if (isa<llvm::IntegerType>(Src->getType())) { 401 bool InputSigned = SrcType->isSignedIntegerType(); 402 if (isa<llvm::IntegerType>(DstTy)) 403 return Builder.CreateIntCast(Src, DstTy, InputSigned, "conv"); 404 else if (InputSigned) 405 return Builder.CreateSIToFP(Src, DstTy, "conv"); 406 else 407 return Builder.CreateUIToFP(Src, DstTy, "conv"); 408 } 409 410 assert(Src->getType()->isFloatingPoint() && "Unknown real conversion"); 411 if (isa<llvm::IntegerType>(DstTy)) { 412 if (DstType->isSignedIntegerType()) 413 return Builder.CreateFPToSI(Src, DstTy, "conv"); 414 else 415 return Builder.CreateFPToUI(Src, DstTy, "conv"); 416 } 417 418 assert(DstTy->isFloatingPoint() && "Unknown real conversion"); 419 if (DstTy->getTypeID() < Src->getType()->getTypeID()) 420 return Builder.CreateFPTrunc(Src, DstTy, "conv"); 421 else 422 return Builder.CreateFPExt(Src, DstTy, "conv"); 423} 424 425/// EmitComplexToScalarConversion - Emit a conversion from the specified 426/// complex type to the specified destination type, where the destination 427/// type is an LLVM scalar type. 428Value *ScalarExprEmitter:: 429EmitComplexToScalarConversion(CodeGenFunction::ComplexPairTy Src, 430 QualType SrcTy, QualType DstTy) { 431 // Get the source element type. 432 SrcTy = SrcTy->getAsComplexType()->getElementType(); 433 434 // Handle conversions to bool first, they are special: comparisons against 0. 435 if (DstTy->isBooleanType()) { 436 // Complex != 0 -> (Real != 0) | (Imag != 0) 437 Src.first = EmitScalarConversion(Src.first, SrcTy, DstTy); 438 Src.second = EmitScalarConversion(Src.second, SrcTy, DstTy); 439 return Builder.CreateOr(Src.first, Src.second, "tobool"); 440 } 441 442 // C99 6.3.1.7p2: "When a value of complex type is converted to a real type, 443 // the imaginary part of the complex value is discarded and the value of the 444 // real part is converted according to the conversion rules for the 445 // corresponding real type. 446 return EmitScalarConversion(Src.first, SrcTy, DstTy); 447} 448 449 450//===----------------------------------------------------------------------===// 451// Visitor Methods 452//===----------------------------------------------------------------------===// 453 454Value *ScalarExprEmitter::VisitExpr(Expr *E) { 455 CGF.WarnUnsupported(E, "scalar expression"); 456 if (E->getType()->isVoidType()) 457 return 0; 458 return llvm::UndefValue::get(CGF.ConvertType(E->getType())); 459} 460 461Value *ScalarExprEmitter::VisitShuffleVectorExpr(ShuffleVectorExpr *E) { 462 llvm::SmallVector<llvm::Constant*, 32> indices; 463 for (unsigned i = 2; i < E->getNumSubExprs(); i++) { 464 indices.push_back(cast<llvm::Constant>(CGF.EmitScalarExpr(E->getExpr(i)))); 465 } 466 Value* V1 = CGF.EmitScalarExpr(E->getExpr(0)); 467 Value* V2 = CGF.EmitScalarExpr(E->getExpr(1)); 468 Value* SV = llvm::ConstantVector::get(indices.begin(), indices.size()); 469 return Builder.CreateShuffleVector(V1, V2, SV, "shuffle"); 470} 471 472Value *ScalarExprEmitter::VisitObjCMessageExpr(ObjCMessageExpr *E) { 473 // Only the lookup mechanism and first two arguments of the method 474 // implementation vary between runtimes. We can get the receiver and 475 // arguments in generic code. 476 477 // Find the receiver 478 llvm::Value *Receiver = CGF.EmitScalarExpr(E->getReceiver()); 479 480 // Process the arguments 481 unsigned ArgC = E->getNumArgs(); 482 llvm::SmallVector<llvm::Value*, 16> Args; 483 for (unsigned i = 0; i != ArgC; ++i) { 484 Expr *ArgExpr = E->getArg(i); 485 QualType ArgTy = ArgExpr->getType(); 486 if (!CGF.hasAggregateLLVMType(ArgTy)) { 487 // Scalar argument is passed by-value. 488 Args.push_back(CGF.EmitScalarExpr(ArgExpr)); 489 } else if (ArgTy->isAnyComplexType()) { 490 // Make a temporary alloca to pass the argument. 491 llvm::Value *DestMem = CGF.CreateTempAlloca(ConvertType(ArgTy)); 492 CGF.EmitComplexExprIntoAddr(ArgExpr, DestMem, false); 493 Args.push_back(DestMem); 494 } else { 495 llvm::Value *DestMem = CGF.CreateTempAlloca(ConvertType(ArgTy)); 496 CGF.EmitAggExpr(ArgExpr, DestMem, false); 497 Args.push_back(DestMem); 498 } 499 } 500 501 return Runtime->GenerateMessageSend(Builder, ConvertType(E->getType()), 502 Receiver, E->getSelector(), 503 &Args[0], Args.size()); 504} 505 506Value *ScalarExprEmitter::VisitObjCSelectorExpr(ObjCSelectorExpr *E) { 507 return Runtime->GetSelector(Builder, E->getSelector()); 508} 509 510Value *ScalarExprEmitter::VisitObjCProtocolExpr(ObjCProtocolExpr *E) { 511 // FIXME: This should pass the Decl not the name. 512 return Runtime->GenerateProtocolRef(Builder, E->getProtocol()->getName()); 513} 514 515Value *ScalarExprEmitter::VisitArraySubscriptExpr(ArraySubscriptExpr *E) { 516 // Emit subscript expressions in rvalue context's. For most cases, this just 517 // loads the lvalue formed by the subscript expr. However, we have to be 518 // careful, because the base of a vector subscript is occasionally an rvalue, 519 // so we can't get it as an lvalue. 520 if (!E->getBase()->getType()->isVectorType()) 521 return EmitLoadOfLValue(E); 522 523 // Handle the vector case. The base must be a vector, the index must be an 524 // integer value. 525 Value *Base = Visit(E->getBase()); 526 Value *Idx = Visit(E->getIdx()); 527 528 // FIXME: Convert Idx to i32 type. 529 return Builder.CreateExtractElement(Base, Idx, "vecext"); 530} 531 532/// VisitImplicitCastExpr - Implicit casts are the same as normal casts, but 533/// also handle things like function to pointer-to-function decay, and array to 534/// pointer decay. 535Value *ScalarExprEmitter::VisitImplicitCastExpr(const ImplicitCastExpr *E) { 536 const Expr *Op = E->getSubExpr(); 537 538 // If this is due to array->pointer conversion, emit the array expression as 539 // an l-value. 540 if (Op->getType()->isArrayType()) { 541 // FIXME: For now we assume that all source arrays map to LLVM arrays. This 542 // will not true when we add support for VLAs. 543 Value *V = EmitLValue(Op).getAddress(); // Bitfields can't be arrays. 544 545 assert(isa<llvm::PointerType>(V->getType()) && 546 isa<llvm::ArrayType>(cast<llvm::PointerType>(V->getType()) 547 ->getElementType()) && 548 "Doesn't support VLAs yet!"); 549 V = Builder.CreateStructGEP(V, 0, "arraydecay"); 550 551 // The resultant pointer type can be implicitly casted to other pointer 552 // types as well (e.g. void*) and can be implicitly converted to integer. 553 const llvm::Type *DestTy = ConvertType(E->getType()); 554 if (V->getType() != DestTy) { 555 if (isa<llvm::PointerType>(DestTy)) 556 V = Builder.CreateBitCast(V, DestTy, "ptrconv"); 557 else { 558 assert(isa<llvm::IntegerType>(DestTy) && "Unknown array decay"); 559 V = Builder.CreatePtrToInt(V, DestTy, "ptrconv"); 560 } 561 } 562 return V; 563 564 } else if (E->getType()->isReferenceType()) { 565 return EmitLValue(Op).getAddress(); 566 } 567 568 return EmitCastExpr(Op, E->getType()); 569} 570 571 572// VisitCastExpr - Emit code for an explicit or implicit cast. Implicit casts 573// have to handle a more broad range of conversions than explicit casts, as they 574// handle things like function to ptr-to-function decay etc. 575Value *ScalarExprEmitter::EmitCastExpr(const Expr *E, QualType DestTy) { 576 // Handle cases where the source is an non-complex type. 577 578 if (!CGF.hasAggregateLLVMType(E->getType())) { 579 Value *Src = Visit(const_cast<Expr*>(E)); 580 581 // Use EmitScalarConversion to perform the conversion. 582 return EmitScalarConversion(Src, E->getType(), DestTy); 583 } 584 585 if (E->getType()->isAnyComplexType()) { 586 // Handle cases where the source is a complex type. 587 return EmitComplexToScalarConversion(CGF.EmitComplexExpr(E), E->getType(), 588 DestTy); 589 } 590 591 // Okay, this is a cast from an aggregate. It must be a cast to void. Just 592 // evaluate the result and return. 593 CGF.EmitAggExpr(E, 0, false); 594 return 0; 595} 596 597Value *ScalarExprEmitter::VisitStmtExpr(const StmtExpr *E) { 598 return CGF.EmitCompoundStmt(*E->getSubStmt(), 599 !E->getType()->isVoidType()).getScalarVal(); 600} 601 602 603//===----------------------------------------------------------------------===// 604// Unary Operators 605//===----------------------------------------------------------------------===// 606 607Value *ScalarExprEmitter::VisitPrePostIncDec(const UnaryOperator *E, 608 bool isInc, bool isPre) { 609 LValue LV = EmitLValue(E->getSubExpr()); 610 // FIXME: Handle volatile! 611 Value *InVal = CGF.EmitLoadOfLValue(LV, // false 612 E->getSubExpr()->getType()).getScalarVal(); 613 614 int AmountVal = isInc ? 1 : -1; 615 616 Value *NextVal; 617 if (isa<llvm::PointerType>(InVal->getType())) { 618 // FIXME: This isn't right for VLAs. 619 NextVal = llvm::ConstantInt::get(llvm::Type::Int32Ty, AmountVal); 620 NextVal = Builder.CreateGEP(InVal, NextVal, "ptrincdec"); 621 } else { 622 // Add the inc/dec to the real part. 623 if (isa<llvm::IntegerType>(InVal->getType())) 624 NextVal = llvm::ConstantInt::get(InVal->getType(), AmountVal); 625 else if (InVal->getType() == llvm::Type::FloatTy) 626 NextVal = 627 llvm::ConstantFP::get(llvm::APFloat(static_cast<float>(AmountVal))); 628 else if (InVal->getType() == llvm::Type::DoubleTy) 629 NextVal = 630 llvm::ConstantFP::get(llvm::APFloat(static_cast<double>(AmountVal))); 631 else { 632 llvm::APFloat F(static_cast<float>(AmountVal)); 633 F.convert(CGF.Target.getLongDoubleFormat(), llvm::APFloat::rmTowardZero); 634 NextVal = llvm::ConstantFP::get(F); 635 } 636 NextVal = Builder.CreateAdd(InVal, NextVal, isInc ? "inc" : "dec"); 637 } 638 639 // Store the updated result through the lvalue. 640 CGF.EmitStoreThroughLValue(RValue::get(NextVal), LV, 641 E->getSubExpr()->getType()); 642 643 // If this is a postinc, return the value read from memory, otherwise use the 644 // updated value. 645 return isPre ? NextVal : InVal; 646} 647 648 649Value *ScalarExprEmitter::VisitUnaryMinus(const UnaryOperator *E) { 650 Value *Op = Visit(E->getSubExpr()); 651 return Builder.CreateNeg(Op, "neg"); 652} 653 654Value *ScalarExprEmitter::VisitUnaryNot(const UnaryOperator *E) { 655 Value *Op = Visit(E->getSubExpr()); 656 return Builder.CreateNot(Op, "neg"); 657} 658 659Value *ScalarExprEmitter::VisitUnaryLNot(const UnaryOperator *E) { 660 // Compare operand to zero. 661 Value *BoolVal = CGF.EvaluateExprAsBool(E->getSubExpr()); 662 663 // Invert value. 664 // TODO: Could dynamically modify easy computations here. For example, if 665 // the operand is an icmp ne, turn into icmp eq. 666 BoolVal = Builder.CreateNot(BoolVal, "lnot"); 667 668 // ZExt result to int. 669 return Builder.CreateZExt(BoolVal, CGF.LLVMIntTy, "lnot.ext"); 670} 671 672/// EmitSizeAlignOf - Return the size or alignment of the 'TypeToSize' type as 673/// an integer (RetType). 674Value *ScalarExprEmitter::EmitSizeAlignOf(QualType TypeToSize, 675 QualType RetType,bool isSizeOf){ 676 assert(RetType->isIntegerType() && "Result type must be an integer!"); 677 uint32_t ResultWidth = 678 static_cast<uint32_t>(CGF.getContext().getTypeSize(RetType)); 679 680 // sizeof(void) and __alignof__(void) = 1 as a gcc extension. Also 681 // for function types. 682 // FIXME: what is alignof a function type in gcc? 683 if (TypeToSize->isVoidType() || TypeToSize->isFunctionType()) 684 return llvm::ConstantInt::get(llvm::APInt(ResultWidth, 1)); 685 686 /// FIXME: This doesn't handle VLAs yet! 687 std::pair<uint64_t, unsigned> Info = CGF.getContext().getTypeInfo(TypeToSize); 688 689 uint64_t Val = isSizeOf ? Info.first : Info.second; 690 Val /= 8; // Return size in bytes, not bits. 691 692 return llvm::ConstantInt::get(llvm::APInt(ResultWidth, Val)); 693} 694 695Value *ScalarExprEmitter::VisitUnaryReal(const UnaryOperator *E) { 696 Expr *Op = E->getSubExpr(); 697 if (Op->getType()->isAnyComplexType()) 698 return CGF.EmitComplexExpr(Op).first; 699 return Visit(Op); 700} 701Value *ScalarExprEmitter::VisitUnaryImag(const UnaryOperator *E) { 702 Expr *Op = E->getSubExpr(); 703 if (Op->getType()->isAnyComplexType()) 704 return CGF.EmitComplexExpr(Op).second; 705 706 // __imag on a scalar returns zero. Emit it the subexpr to ensure side 707 // effects are evaluated. 708 CGF.EmitScalarExpr(Op); 709 return llvm::Constant::getNullValue(ConvertType(E->getType())); 710} 711 712Value *ScalarExprEmitter::VisitUnaryOffsetOf(const UnaryOperator *E) 713{ 714 int64_t Val = E->evaluateOffsetOf(CGF.getContext()); 715 716 assert(E->getType()->isIntegerType() && "Result type must be an integer!"); 717 718 uint32_t ResultWidth = 719 static_cast<uint32_t>(CGF.getContext().getTypeSize(E->getType())); 720 return llvm::ConstantInt::get(llvm::APInt(ResultWidth, Val)); 721} 722 723//===----------------------------------------------------------------------===// 724// Binary Operators 725//===----------------------------------------------------------------------===// 726 727BinOpInfo ScalarExprEmitter::EmitBinOps(const BinaryOperator *E) { 728 BinOpInfo Result; 729 Result.LHS = Visit(E->getLHS()); 730 Result.RHS = Visit(E->getRHS()); 731 Result.Ty = E->getType(); 732 Result.E = E; 733 return Result; 734} 735 736Value *ScalarExprEmitter::EmitCompoundAssign(const CompoundAssignOperator *E, 737 Value *(ScalarExprEmitter::*Func)(const BinOpInfo &)) { 738 QualType LHSTy = E->getLHS()->getType(), RHSTy = E->getRHS()->getType(); 739 740 BinOpInfo OpInfo; 741 742 // Load the LHS and RHS operands. 743 LValue LHSLV = EmitLValue(E->getLHS()); 744 OpInfo.LHS = EmitLoadOfLValue(LHSLV, LHSTy); 745 746 // Determine the computation type. If the RHS is complex, then this is one of 747 // the add/sub/mul/div operators. All of these operators can be computed in 748 // with just their real component even though the computation domain really is 749 // complex. 750 QualType ComputeType = E->getComputationType(); 751 752 // If the computation type is complex, then the RHS is complex. Emit the RHS. 753 if (const ComplexType *CT = ComputeType->getAsComplexType()) { 754 ComputeType = CT->getElementType(); 755 756 // Emit the RHS, only keeping the real component. 757 OpInfo.RHS = CGF.EmitComplexExpr(E->getRHS()).first; 758 RHSTy = RHSTy->getAsComplexType()->getElementType(); 759 } else { 760 // Otherwise the RHS is a simple scalar value. 761 OpInfo.RHS = Visit(E->getRHS()); 762 } 763 764 QualType LComputeTy, RComputeTy, ResultTy; 765 766 // Compound assignment does not contain enough information about all 767 // the types involved for pointer arithmetic cases. Figure it out 768 // here for now. 769 if (E->getLHS()->getType()->isPointerType()) { 770 // Pointer arithmetic cases: ptr +=,-= int and ptr -= ptr, 771 assert((E->getOpcode() == BinaryOperator::AddAssign || 772 E->getOpcode() == BinaryOperator::SubAssign) && 773 "Invalid compound assignment operator on pointer type."); 774 LComputeTy = E->getLHS()->getType(); 775 776 if (E->getRHS()->getType()->isPointerType()) { 777 // Degenerate case of (ptr -= ptr) allowed by GCC implicit cast 778 // extension, the conversion from the pointer difference back to 779 // the LHS type is handled at the end. 780 assert(E->getOpcode() == BinaryOperator::SubAssign && 781 "Invalid compound assignment operator on pointer type."); 782 RComputeTy = E->getLHS()->getType(); 783 ResultTy = CGF.getContext().getPointerDiffType(); 784 } else { 785 RComputeTy = E->getRHS()->getType(); 786 ResultTy = LComputeTy; 787 } 788 } else if (E->getRHS()->getType()->isPointerType()) { 789 // Degenerate case of (int += ptr) allowed by GCC implicit cast 790 // extension. 791 assert(E->getOpcode() == BinaryOperator::AddAssign && 792 "Invalid compound assignment operator on pointer type."); 793 LComputeTy = E->getLHS()->getType(); 794 RComputeTy = E->getRHS()->getType(); 795 ResultTy = RComputeTy; 796 } else { 797 LComputeTy = RComputeTy = ResultTy = ComputeType; 798 } 799 800 // Convert the LHS/RHS values to the computation type. 801 OpInfo.LHS = EmitScalarConversion(OpInfo.LHS, LHSTy, LComputeTy); 802 OpInfo.RHS = EmitScalarConversion(OpInfo.RHS, RHSTy, RComputeTy); 803 OpInfo.Ty = ResultTy; 804 OpInfo.E = E; 805 806 // Expand the binary operator. 807 Value *Result = (this->*Func)(OpInfo); 808 809 // Convert the result back to the LHS type. 810 Result = EmitScalarConversion(Result, ResultTy, LHSTy); 811 812 // Store the result value into the LHS lvalue. 813 CGF.EmitStoreThroughLValue(RValue::get(Result), LHSLV, LHSTy); 814 815 // For bitfields, we need the value in the bitfield 816 // FIXME: This adds an extra bitfield load 817 if (LHSLV.isBitfield()) 818 Result = EmitLoadOfLValue(LHSLV, LHSTy); 819 820 return Result; 821} 822 823 824Value *ScalarExprEmitter::EmitDiv(const BinOpInfo &Ops) { 825 if (Ops.LHS->getType()->isFPOrFPVector()) 826 return Builder.CreateFDiv(Ops.LHS, Ops.RHS, "div"); 827 else if (Ops.Ty->isUnsignedIntegerType()) 828 return Builder.CreateUDiv(Ops.LHS, Ops.RHS, "div"); 829 else 830 return Builder.CreateSDiv(Ops.LHS, Ops.RHS, "div"); 831} 832 833Value *ScalarExprEmitter::EmitRem(const BinOpInfo &Ops) { 834 // Rem in C can't be a floating point type: C99 6.5.5p2. 835 if (Ops.Ty->isUnsignedIntegerType()) 836 return Builder.CreateURem(Ops.LHS, Ops.RHS, "rem"); 837 else 838 return Builder.CreateSRem(Ops.LHS, Ops.RHS, "rem"); 839} 840 841 842Value *ScalarExprEmitter::EmitAdd(const BinOpInfo &Ops) { 843 if (!Ops.Ty->isPointerType()) 844 return Builder.CreateAdd(Ops.LHS, Ops.RHS, "add"); 845 846 // FIXME: What about a pointer to a VLA? 847 Value *Ptr, *Idx; 848 Expr *IdxExp; 849 if (isa<llvm::PointerType>(Ops.LHS->getType())) { // pointer + int 850 Ptr = Ops.LHS; 851 Idx = Ops.RHS; 852 IdxExp = Ops.E->getRHS(); 853 } else { // int + pointer 854 Ptr = Ops.RHS; 855 Idx = Ops.LHS; 856 IdxExp = Ops.E->getLHS(); 857 } 858 859 unsigned Width = cast<llvm::IntegerType>(Idx->getType())->getBitWidth(); 860 if (Width < CGF.LLVMPointerWidth) { 861 // Zero or sign extend the pointer value based on whether the index is 862 // signed or not. 863 const llvm::Type *IdxType = llvm::IntegerType::get(CGF.LLVMPointerWidth); 864 if (IdxExp->getType()->isSignedIntegerType()) 865 Idx = Builder.CreateSExt(Idx, IdxType, "idx.ext"); 866 else 867 Idx = Builder.CreateZExt(Idx, IdxType, "idx.ext"); 868 } 869 870 return Builder.CreateGEP(Ptr, Idx, "add.ptr"); 871} 872 873Value *ScalarExprEmitter::EmitSub(const BinOpInfo &Ops) { 874 if (!isa<llvm::PointerType>(Ops.LHS->getType())) 875 return Builder.CreateSub(Ops.LHS, Ops.RHS, "sub"); 876 877 if (!isa<llvm::PointerType>(Ops.RHS->getType())) { 878 // pointer - int 879 Value *Idx = Ops.RHS; 880 unsigned Width = cast<llvm::IntegerType>(Idx->getType())->getBitWidth(); 881 if (Width < CGF.LLVMPointerWidth) { 882 // Zero or sign extend the pointer value based on whether the index is 883 // signed or not. 884 const llvm::Type *IdxType = llvm::IntegerType::get(CGF.LLVMPointerWidth); 885 if (Ops.E->getRHS()->getType()->isSignedIntegerType()) 886 Idx = Builder.CreateSExt(Idx, IdxType, "idx.ext"); 887 else 888 Idx = Builder.CreateZExt(Idx, IdxType, "idx.ext"); 889 } 890 Idx = Builder.CreateNeg(Idx, "sub.ptr.neg"); 891 892 // FIXME: The pointer could point to a VLA. 893 // The GNU void* - int case is automatically handled here because 894 // our LLVM type for void* is i8*. 895 return Builder.CreateGEP(Ops.LHS, Idx, "sub.ptr"); 896 } else { 897 // pointer - pointer 898 Value *LHS = Ops.LHS; 899 Value *RHS = Ops.RHS; 900 901 const QualType LHSType = Ops.E->getLHS()->getType(); 902 const QualType LHSElementType = LHSType->getAsPointerType()->getPointeeType(); 903 uint64_t ElementSize; 904 905 // Handle GCC extension for pointer arithmetic on void* types. 906 if (LHSElementType->isVoidType()) { 907 ElementSize = 1; 908 } else { 909 ElementSize = CGF.getContext().getTypeSize(LHSElementType) / 8; 910 } 911 912 const llvm::Type *ResultType = ConvertType(Ops.Ty); 913 LHS = Builder.CreatePtrToInt(LHS, ResultType, "sub.ptr.lhs.cast"); 914 RHS = Builder.CreatePtrToInt(RHS, ResultType, "sub.ptr.rhs.cast"); 915 Value *BytesBetween = Builder.CreateSub(LHS, RHS, "sub.ptr.sub"); 916 917 // HACK: LLVM doesn't have an divide instruction that 'knows' there is no 918 // remainder. As such, we handle common power-of-two cases here to generate 919 // better code. See PR2247. 920 if (llvm::isPowerOf2_64(ElementSize)) { 921 Value *ShAmt = 922 llvm::ConstantInt::get(ResultType, llvm::Log2_64(ElementSize)); 923 return Builder.CreateAShr(BytesBetween, ShAmt, "sub.ptr.shr"); 924 } 925 926 // Otherwise, do a full sdiv. 927 Value *BytesPerElt = llvm::ConstantInt::get(ResultType, ElementSize); 928 return Builder.CreateSDiv(BytesBetween, BytesPerElt, "sub.ptr.div"); 929 } 930} 931 932Value *ScalarExprEmitter::EmitShl(const BinOpInfo &Ops) { 933 // LLVM requires the LHS and RHS to be the same type: promote or truncate the 934 // RHS to the same size as the LHS. 935 Value *RHS = Ops.RHS; 936 if (Ops.LHS->getType() != RHS->getType()) 937 RHS = Builder.CreateIntCast(RHS, Ops.LHS->getType(), false, "sh_prom"); 938 939 return Builder.CreateShl(Ops.LHS, RHS, "shl"); 940} 941 942Value *ScalarExprEmitter::EmitShr(const BinOpInfo &Ops) { 943 // LLVM requires the LHS and RHS to be the same type: promote or truncate the 944 // RHS to the same size as the LHS. 945 Value *RHS = Ops.RHS; 946 if (Ops.LHS->getType() != RHS->getType()) 947 RHS = Builder.CreateIntCast(RHS, Ops.LHS->getType(), false, "sh_prom"); 948 949 if (Ops.Ty->isUnsignedIntegerType()) 950 return Builder.CreateLShr(Ops.LHS, RHS, "shr"); 951 return Builder.CreateAShr(Ops.LHS, RHS, "shr"); 952} 953 954Value *ScalarExprEmitter::EmitCompare(const BinaryOperator *E,unsigned UICmpOpc, 955 unsigned SICmpOpc, unsigned FCmpOpc) { 956 Value *Result; 957 QualType LHSTy = E->getLHS()->getType(); 958 if (!LHSTy->isAnyComplexType() && !LHSTy->isVectorType()) { 959 Value *LHS = Visit(E->getLHS()); 960 Value *RHS = Visit(E->getRHS()); 961 962 if (LHS->getType()->isFloatingPoint()) { 963 Result = Builder.CreateFCmp((llvm::CmpInst::Predicate)FCmpOpc, 964 LHS, RHS, "cmp"); 965 } else if (LHSTy->isSignedIntegerType()) { 966 Result = Builder.CreateICmp((llvm::ICmpInst::Predicate)SICmpOpc, 967 LHS, RHS, "cmp"); 968 } else { 969 // Unsigned integers and pointers. 970 Result = Builder.CreateICmp((llvm::ICmpInst::Predicate)UICmpOpc, 971 LHS, RHS, "cmp"); 972 } 973 } else if (LHSTy->isVectorType()) { 974 Value *LHS = Visit(E->getLHS()); 975 Value *RHS = Visit(E->getRHS()); 976 977 if (LHS->getType()->isFPOrFPVector()) { 978 Result = Builder.CreateVFCmp((llvm::CmpInst::Predicate)FCmpOpc, 979 LHS, RHS, "cmp"); 980 } else if (LHSTy->isUnsignedIntegerType()) { 981 Result = Builder.CreateVICmp((llvm::CmpInst::Predicate)UICmpOpc, 982 LHS, RHS, "cmp"); 983 } else { 984 // Signed integers and pointers. 985 Result = Builder.CreateVICmp((llvm::CmpInst::Predicate)SICmpOpc, 986 LHS, RHS, "cmp"); 987 } 988 return Result; 989 } else { 990 // Complex Comparison: can only be an equality comparison. 991 CodeGenFunction::ComplexPairTy LHS = CGF.EmitComplexExpr(E->getLHS()); 992 CodeGenFunction::ComplexPairTy RHS = CGF.EmitComplexExpr(E->getRHS()); 993 994 QualType CETy = LHSTy->getAsComplexType()->getElementType(); 995 996 Value *ResultR, *ResultI; 997 if (CETy->isRealFloatingType()) { 998 ResultR = Builder.CreateFCmp((llvm::FCmpInst::Predicate)FCmpOpc, 999 LHS.first, RHS.first, "cmp.r"); 1000 ResultI = Builder.CreateFCmp((llvm::FCmpInst::Predicate)FCmpOpc, 1001 LHS.second, RHS.second, "cmp.i"); 1002 } else { 1003 // Complex comparisons can only be equality comparisons. As such, signed 1004 // and unsigned opcodes are the same. 1005 ResultR = Builder.CreateICmp((llvm::ICmpInst::Predicate)UICmpOpc, 1006 LHS.first, RHS.first, "cmp.r"); 1007 ResultI = Builder.CreateICmp((llvm::ICmpInst::Predicate)UICmpOpc, 1008 LHS.second, RHS.second, "cmp.i"); 1009 } 1010 1011 if (E->getOpcode() == BinaryOperator::EQ) { 1012 Result = Builder.CreateAnd(ResultR, ResultI, "and.ri"); 1013 } else { 1014 assert(E->getOpcode() == BinaryOperator::NE && 1015 "Complex comparison other than == or != ?"); 1016 Result = Builder.CreateOr(ResultR, ResultI, "or.ri"); 1017 } 1018 } 1019 1020 // ZExt result to int. 1021 return Builder.CreateZExt(Result, CGF.LLVMIntTy, "cmp.ext"); 1022} 1023 1024Value *ScalarExprEmitter::VisitBinAssign(const BinaryOperator *E) { 1025 LValue LHS = EmitLValue(E->getLHS()); 1026 Value *RHS = Visit(E->getRHS()); 1027 1028 // Store the value into the LHS. 1029 // FIXME: Volatility! 1030 CGF.EmitStoreThroughLValue(RValue::get(RHS), LHS, E->getType()); 1031 1032 // For bitfields, we need the value in the bitfield 1033 // FIXME: This adds an extra bitfield load 1034 if (LHS.isBitfield()) 1035 return EmitLoadOfLValue(LHS, E->getLHS()->getType()); 1036 // Return the RHS. 1037 return RHS; 1038} 1039 1040Value *ScalarExprEmitter::VisitBinLAnd(const BinaryOperator *E) { 1041 Value *LHSCond = CGF.EvaluateExprAsBool(E->getLHS()); 1042 1043 llvm::BasicBlock *ContBlock = llvm::BasicBlock::Create("land_cont"); 1044 llvm::BasicBlock *RHSBlock = llvm::BasicBlock::Create("land_rhs"); 1045 1046 llvm::BasicBlock *OrigBlock = Builder.GetInsertBlock(); 1047 Builder.CreateCondBr(LHSCond, RHSBlock, ContBlock); 1048 1049 CGF.EmitBlock(RHSBlock); 1050 Value *RHSCond = CGF.EvaluateExprAsBool(E->getRHS()); 1051 1052 // Reaquire the RHS block, as there may be subblocks inserted. 1053 RHSBlock = Builder.GetInsertBlock(); 1054 CGF.EmitBlock(ContBlock); 1055 1056 // Create a PHI node. If we just evaluted the LHS condition, the result is 1057 // false. If we evaluated both, the result is the RHS condition. 1058 llvm::PHINode *PN = Builder.CreatePHI(llvm::Type::Int1Ty, "land"); 1059 PN->reserveOperandSpace(2); 1060 PN->addIncoming(llvm::ConstantInt::getFalse(), OrigBlock); 1061 PN->addIncoming(RHSCond, RHSBlock); 1062 1063 // ZExt result to int. 1064 return Builder.CreateZExt(PN, CGF.LLVMIntTy, "land.ext"); 1065} 1066 1067Value *ScalarExprEmitter::VisitBinLOr(const BinaryOperator *E) { 1068 Value *LHSCond = CGF.EvaluateExprAsBool(E->getLHS()); 1069 1070 llvm::BasicBlock *ContBlock = llvm::BasicBlock::Create("lor_cont"); 1071 llvm::BasicBlock *RHSBlock = llvm::BasicBlock::Create("lor_rhs"); 1072 1073 llvm::BasicBlock *OrigBlock = Builder.GetInsertBlock(); 1074 Builder.CreateCondBr(LHSCond, ContBlock, RHSBlock); 1075 1076 CGF.EmitBlock(RHSBlock); 1077 Value *RHSCond = CGF.EvaluateExprAsBool(E->getRHS()); 1078 1079 // Reaquire the RHS block, as there may be subblocks inserted. 1080 RHSBlock = Builder.GetInsertBlock(); 1081 CGF.EmitBlock(ContBlock); 1082 1083 // Create a PHI node. If we just evaluted the LHS condition, the result is 1084 // true. If we evaluated both, the result is the RHS condition. 1085 llvm::PHINode *PN = Builder.CreatePHI(llvm::Type::Int1Ty, "lor"); 1086 PN->reserveOperandSpace(2); 1087 PN->addIncoming(llvm::ConstantInt::getTrue(), OrigBlock); 1088 PN->addIncoming(RHSCond, RHSBlock); 1089 1090 // ZExt result to int. 1091 return Builder.CreateZExt(PN, CGF.LLVMIntTy, "lor.ext"); 1092} 1093 1094Value *ScalarExprEmitter::VisitBinComma(const BinaryOperator *E) { 1095 CGF.EmitStmt(E->getLHS()); 1096 return Visit(E->getRHS()); 1097} 1098 1099//===----------------------------------------------------------------------===// 1100// Other Operators 1101//===----------------------------------------------------------------------===// 1102 1103Value *ScalarExprEmitter:: 1104VisitConditionalOperator(const ConditionalOperator *E) { 1105 llvm::BasicBlock *LHSBlock = llvm::BasicBlock::Create("cond.?"); 1106 llvm::BasicBlock *RHSBlock = llvm::BasicBlock::Create("cond.:"); 1107 llvm::BasicBlock *ContBlock = llvm::BasicBlock::Create("cond.cont"); 1108 1109 // Evaluate the conditional, then convert it to bool. We do this explicitly 1110 // because we need the unconverted value if this is a GNU ?: expression with 1111 // missing middle value. 1112 Value *CondVal = CGF.EmitScalarExpr(E->getCond()); 1113 Value *CondBoolVal =CGF.EmitScalarConversion(CondVal, E->getCond()->getType(), 1114 CGF.getContext().BoolTy); 1115 Builder.CreateCondBr(CondBoolVal, LHSBlock, RHSBlock); 1116 1117 CGF.EmitBlock(LHSBlock); 1118 1119 // Handle the GNU extension for missing LHS. 1120 Value *LHS; 1121 if (E->getLHS()) 1122 LHS = Visit(E->getLHS()); 1123 else // Perform promotions, to handle cases like "short ?: int" 1124 LHS = EmitScalarConversion(CondVal, E->getCond()->getType(), E->getType()); 1125 1126 Builder.CreateBr(ContBlock); 1127 LHSBlock = Builder.GetInsertBlock(); 1128 1129 CGF.EmitBlock(RHSBlock); 1130 1131 Value *RHS = Visit(E->getRHS()); 1132 Builder.CreateBr(ContBlock); 1133 RHSBlock = Builder.GetInsertBlock(); 1134 1135 CGF.EmitBlock(ContBlock); 1136 1137 if (!LHS || !RHS) { 1138 assert(E->getType()->isVoidType() && "Non-void value should have a value"); 1139 return 0; 1140 } 1141 1142 // Create a PHI node for the real part. 1143 llvm::PHINode *PN = Builder.CreatePHI(LHS->getType(), "cond"); 1144 PN->reserveOperandSpace(2); 1145 PN->addIncoming(LHS, LHSBlock); 1146 PN->addIncoming(RHS, RHSBlock); 1147 return PN; 1148} 1149 1150Value *ScalarExprEmitter::VisitChooseExpr(ChooseExpr *E) { 1151 // Emit the LHS or RHS as appropriate. 1152 return 1153 Visit(E->isConditionTrue(CGF.getContext()) ? E->getLHS() : E->getRHS()); 1154} 1155 1156Value *ScalarExprEmitter::VisitOverloadExpr(OverloadExpr *E) { 1157 return CGF.EmitCallExpr(E->getFn(), E->arg_begin(), 1158 E->arg_end(CGF.getContext())).getScalarVal(); 1159} 1160 1161Value *ScalarExprEmitter::VisitVAArgExpr(VAArgExpr *VE) { 1162 llvm::Value *ArgValue = EmitLValue(VE->getSubExpr()).getAddress(); 1163 1164 llvm::Value *V = Builder.CreateVAArg(ArgValue, ConvertType(VE->getType())); 1165 return V; 1166} 1167 1168Value *ScalarExprEmitter::VisitObjCEncodeExpr(const ObjCEncodeExpr *E) { 1169 std::string str; 1170 llvm::SmallVector<const RecordType *, 8> EncodingRecordTypes; 1171 CGF.getContext().getObjCEncodingForType(E->getEncodedType(), str, 1172 EncodingRecordTypes); 1173 1174 llvm::Constant *C = llvm::ConstantArray::get(str); 1175 C = new llvm::GlobalVariable(C->getType(), true, 1176 llvm::GlobalValue::InternalLinkage, 1177 C, ".str", &CGF.CGM.getModule()); 1178 llvm::Constant *Zero = llvm::Constant::getNullValue(llvm::Type::Int32Ty); 1179 llvm::Constant *Zeros[] = { Zero, Zero }; 1180 C = llvm::ConstantExpr::getGetElementPtr(C, Zeros, 2); 1181 1182 return C; 1183} 1184 1185//===----------------------------------------------------------------------===// 1186// Entry Point into this File 1187//===----------------------------------------------------------------------===// 1188 1189/// EmitComplexExpr - Emit the computation of the specified expression of 1190/// complex type, ignoring the result. 1191Value *CodeGenFunction::EmitScalarExpr(const Expr *E) { 1192 assert(E && !hasAggregateLLVMType(E->getType()) && 1193 "Invalid scalar expression to emit"); 1194 1195 return ScalarExprEmitter(*this).Visit(const_cast<Expr*>(E)); 1196} 1197 1198/// EmitScalarConversion - Emit a conversion from the specified type to the 1199/// specified destination type, both of which are LLVM scalar types. 1200Value *CodeGenFunction::EmitScalarConversion(Value *Src, QualType SrcTy, 1201 QualType DstTy) { 1202 assert(!hasAggregateLLVMType(SrcTy) && !hasAggregateLLVMType(DstTy) && 1203 "Invalid scalar expression to emit"); 1204 return ScalarExprEmitter(*this).EmitScalarConversion(Src, SrcTy, DstTy); 1205} 1206 1207/// EmitComplexToScalarConversion - Emit a conversion from the specified 1208/// complex type to the specified destination type, where the destination 1209/// type is an LLVM scalar type. 1210Value *CodeGenFunction::EmitComplexToScalarConversion(ComplexPairTy Src, 1211 QualType SrcTy, 1212 QualType DstTy) { 1213 assert(SrcTy->isAnyComplexType() && !hasAggregateLLVMType(DstTy) && 1214 "Invalid complex -> scalar conversion"); 1215 return ScalarExprEmitter(*this).EmitComplexToScalarConversion(Src, SrcTy, 1216 DstTy); 1217} 1218 1219Value *CodeGenFunction::EmitShuffleVector(Value* V1, Value *V2, ...) { 1220 assert(V1->getType() == V2->getType() && 1221 "Vector operands must be of the same type"); 1222 unsigned NumElements = 1223 cast<llvm::VectorType>(V1->getType())->getNumElements(); 1224 1225 va_list va; 1226 va_start(va, V2); 1227 1228 llvm::SmallVector<llvm::Constant*, 16> Args; 1229 for (unsigned i = 0; i < NumElements; i++) { 1230 int n = va_arg(va, int); 1231 assert(n >= 0 && n < (int)NumElements * 2 && 1232 "Vector shuffle index out of bounds!"); 1233 Args.push_back(llvm::ConstantInt::get(llvm::Type::Int32Ty, n)); 1234 } 1235 1236 const char *Name = va_arg(va, const char *); 1237 va_end(va); 1238 1239 llvm::Constant *Mask = llvm::ConstantVector::get(&Args[0], NumElements); 1240 1241 return Builder.CreateShuffleVector(V1, V2, Mask, Name); 1242} 1243 1244llvm::Value *CodeGenFunction::EmitVector(llvm::Value * const *Vals, 1245 unsigned NumVals, bool isSplat) { 1246 llvm::Value *Vec 1247 = llvm::UndefValue::get(llvm::VectorType::get(Vals[0]->getType(), NumVals)); 1248 1249 for (unsigned i = 0, e = NumVals; i != e; ++i) { 1250 llvm::Value *Val = isSplat ? Vals[0] : Vals[i]; 1251 llvm::Value *Idx = llvm::ConstantInt::get(llvm::Type::Int32Ty, i); 1252 Vec = Builder.CreateInsertElement(Vec, Val, Idx, "tmp"); 1253 } 1254 1255 return Vec; 1256} 1257