CGExprScalar.cpp revision ee5a700af3fe9ae1a639c271f093f40677dddc04
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 48public: 49 50 ScalarExprEmitter(CodeGenFunction &cgf) : CGF(cgf), 51 Builder(CGF.Builder) { 52 } 53 54 //===--------------------------------------------------------------------===// 55 // Utilities 56 //===--------------------------------------------------------------------===// 57 58 const llvm::Type *ConvertType(QualType T) { return CGF.ConvertType(T); } 59 LValue EmitLValue(const Expr *E) { return CGF.EmitLValue(E); } 60 61 Value *EmitLoadOfLValue(LValue LV, QualType T) { 62 return CGF.EmitLoadOfLValue(LV, T).getScalarVal(); 63 } 64 65 /// EmitLoadOfLValue - Given an expression with complex type that represents a 66 /// value l-value, this method emits the address of the l-value, then loads 67 /// and returns the result. 68 Value *EmitLoadOfLValue(const Expr *E) { 69 // FIXME: Volatile 70 return EmitLoadOfLValue(EmitLValue(E), E->getType()); 71 } 72 73 /// EmitConversionToBool - Convert the specified expression value to a 74 /// boolean (i1) truth value. This is equivalent to "Val != 0". 75 Value *EmitConversionToBool(Value *Src, QualType DstTy); 76 77 /// EmitScalarConversion - Emit a conversion from the specified type to the 78 /// specified destination type, both of which are LLVM scalar types. 79 Value *EmitScalarConversion(Value *Src, QualType SrcTy, QualType DstTy); 80 81 /// EmitComplexToScalarConversion - Emit a conversion from the specified 82 /// complex type to the specified destination type, where the destination 83 /// type is an LLVM scalar type. 84 Value *EmitComplexToScalarConversion(CodeGenFunction::ComplexPairTy Src, 85 QualType SrcTy, QualType DstTy); 86 87 //===--------------------------------------------------------------------===// 88 // Visitor Methods 89 //===--------------------------------------------------------------------===// 90 91 Value *VisitStmt(Stmt *S) { 92 S->dump(CGF.getContext().getSourceManager()); 93 assert(0 && "Stmt can't have complex result type!"); 94 return 0; 95 } 96 Value *VisitExpr(Expr *S); 97 Value *VisitParenExpr(ParenExpr *PE) { return Visit(PE->getSubExpr()); } 98 99 // Leaves. 100 Value *VisitIntegerLiteral(const IntegerLiteral *E) { 101 return llvm::ConstantInt::get(E->getValue()); 102 } 103 Value *VisitFloatingLiteral(const FloatingLiteral *E) { 104 return llvm::ConstantFP::get(E->getValue()); 105 } 106 Value *VisitCharacterLiteral(const CharacterLiteral *E) { 107 return llvm::ConstantInt::get(ConvertType(E->getType()), E->getValue()); 108 } 109 Value *VisitCXXBoolLiteralExpr(const CXXBoolLiteralExpr *E) { 110 return llvm::ConstantInt::get(ConvertType(E->getType()), E->getValue()); 111 } 112 Value *VisitCXXZeroInitValueExpr(const CXXZeroInitValueExpr *E) { 113 return llvm::Constant::getNullValue(ConvertType(E->getType())); 114 } 115 Value *VisitTypesCompatibleExpr(const TypesCompatibleExpr *E) { 116 return llvm::ConstantInt::get(ConvertType(E->getType()), 117 CGF.getContext().typesAreCompatible( 118 E->getArgType1(), E->getArgType2())); 119 } 120 Value *VisitSizeOfAlignOfTypeExpr(const SizeOfAlignOfTypeExpr *E) { 121 return EmitSizeAlignOf(E->getArgumentType(), E->getType(), E->isSizeOf()); 122 } 123 Value *VisitAddrLabelExpr(const AddrLabelExpr *E) { 124 llvm::Value *V = 125 llvm::ConstantInt::get(llvm::Type::Int32Ty, 126 CGF.GetIDForAddrOfLabel(E->getLabel())); 127 128 return Builder.CreateIntToPtr(V, ConvertType(E->getType())); 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 *VisitObjCSelectorExpr(ObjCSelectorExpr *E) { 138 return CGF.EmitObjCSelectorExpr(E); 139 } 140 Value *VisitObjCProtocolExpr(ObjCProtocolExpr *E) { 141 return CGF.EmitObjCProtocolExpr(E); 142 } 143 Value *VisitObjCIvarRefExpr(ObjCIvarRefExpr *E) { 144 return EmitLoadOfLValue(E); 145 } 146 Value *VisitObjCPropertyRefExpr(ObjCPropertyRefExpr *E) { 147 return EmitLoadOfLValue(E); 148 } 149 Value *VisitObjCMessageExpr(ObjCMessageExpr *E) { 150 return CGF.EmitObjCMessageExpr(E).getScalarVal(); 151 } 152 153 Value *VisitArraySubscriptExpr(ArraySubscriptExpr *E); 154 Value *VisitShuffleVectorExpr(ShuffleVectorExpr *E); 155 Value *VisitMemberExpr(Expr *E) { return EmitLoadOfLValue(E); } 156 Value *VisitExtVectorElementExpr(Expr *E) { return EmitLoadOfLValue(E); } 157 Value *VisitCompoundLiteralExpr(CompoundLiteralExpr *E) { return EmitLoadOfLValue(E); } 158 Value *VisitStringLiteral(Expr *E) { return EmitLValue(E).getAddress(); } 159 Value *VisitPredefinedExpr(Expr *E) { return EmitLValue(E).getAddress(); } 160 161 Value *VisitInitListExpr(InitListExpr *E) { 162 unsigned NumInitElements = E->getNumInits(); 163 164 const llvm::VectorType *VType = 165 dyn_cast<llvm::VectorType>(ConvertType(E->getType())); 166 167 // We have a scalar in braces. Just use the first element. 168 if (!VType) 169 return Visit(E->getInit(0)); 170 171 unsigned NumVectorElements = VType->getNumElements(); 172 const llvm::Type *ElementType = VType->getElementType(); 173 174 // Emit individual vector element stores. 175 llvm::Value *V = llvm::UndefValue::get(VType); 176 177 // Emit initializers 178 unsigned i; 179 for (i = 0; i < NumInitElements; ++i) { 180 Value *NewV = Visit(E->getInit(i)); 181 Value *Idx = llvm::ConstantInt::get(llvm::Type::Int32Ty, i); 182 V = Builder.CreateInsertElement(V, NewV, Idx); 183 } 184 185 // Emit remaining default initializers 186 for (/* Do not initialize i*/; i < NumVectorElements; ++i) { 187 Value *Idx = llvm::ConstantInt::get(llvm::Type::Int32Ty, i); 188 llvm::Value *NewV = llvm::Constant::getNullValue(ElementType); 189 V = Builder.CreateInsertElement(V, NewV, Idx); 190 } 191 192 return V; 193 } 194 195 Value *VisitImplicitCastExpr(const ImplicitCastExpr *E); 196 Value *VisitCastExpr(const CastExpr *E) { 197 return EmitCastExpr(E->getSubExpr(), E->getType()); 198 } 199 Value *EmitCastExpr(const Expr *E, QualType T); 200 201 Value *VisitCallExpr(const CallExpr *E) { 202 return CGF.EmitCallExpr(E).getScalarVal(); 203 } 204 205 Value *VisitStmtExpr(const StmtExpr *E); 206 207 // Unary Operators. 208 Value *VisitPrePostIncDec(const UnaryOperator *E, bool isInc, bool isPre); 209 Value *VisitUnaryPostDec(const UnaryOperator *E) { 210 return VisitPrePostIncDec(E, false, false); 211 } 212 Value *VisitUnaryPostInc(const UnaryOperator *E) { 213 return VisitPrePostIncDec(E, true, false); 214 } 215 Value *VisitUnaryPreDec(const UnaryOperator *E) { 216 return VisitPrePostIncDec(E, false, true); 217 } 218 Value *VisitUnaryPreInc(const UnaryOperator *E) { 219 return VisitPrePostIncDec(E, true, true); 220 } 221 Value *VisitUnaryAddrOf(const UnaryOperator *E) { 222 return EmitLValue(E->getSubExpr()).getAddress(); 223 } 224 Value *VisitUnaryDeref(const Expr *E) { return EmitLoadOfLValue(E); } 225 Value *VisitUnaryPlus(const UnaryOperator *E) { 226 return Visit(E->getSubExpr()); 227 } 228 Value *VisitUnaryMinus (const UnaryOperator *E); 229 Value *VisitUnaryNot (const UnaryOperator *E); 230 Value *VisitUnaryLNot (const UnaryOperator *E); 231 Value *VisitUnarySizeOf (const UnaryOperator *E) { 232 return EmitSizeAlignOf(E->getSubExpr()->getType(), E->getType(), true); 233 } 234 Value *VisitUnaryAlignOf (const UnaryOperator *E) { 235 return EmitSizeAlignOf(E->getSubExpr()->getType(), E->getType(), false); 236 } 237 Value *EmitSizeAlignOf(QualType TypeToSize, QualType RetType, 238 bool isSizeOf); 239 Value *VisitUnaryReal (const UnaryOperator *E); 240 Value *VisitUnaryImag (const UnaryOperator *E); 241 Value *VisitUnaryExtension(const UnaryOperator *E) { 242 return Visit(E->getSubExpr()); 243 } 244 Value *VisitUnaryOffsetOf(const UnaryOperator *E); 245 Value *VisitCXXDefaultArgExpr(CXXDefaultArgExpr *DAE) { 246 return Visit(DAE->getExpr()); 247 } 248 249 // Binary Operators. 250 Value *EmitMul(const BinOpInfo &Ops) { 251 return Builder.CreateMul(Ops.LHS, Ops.RHS, "mul"); 252 } 253 Value *EmitDiv(const BinOpInfo &Ops); 254 Value *EmitRem(const BinOpInfo &Ops); 255 Value *EmitAdd(const BinOpInfo &Ops); 256 Value *EmitSub(const BinOpInfo &Ops); 257 Value *EmitShl(const BinOpInfo &Ops); 258 Value *EmitShr(const BinOpInfo &Ops); 259 Value *EmitAnd(const BinOpInfo &Ops) { 260 return Builder.CreateAnd(Ops.LHS, Ops.RHS, "and"); 261 } 262 Value *EmitXor(const BinOpInfo &Ops) { 263 return Builder.CreateXor(Ops.LHS, Ops.RHS, "xor"); 264 } 265 Value *EmitOr (const BinOpInfo &Ops) { 266 return Builder.CreateOr(Ops.LHS, Ops.RHS, "or"); 267 } 268 269 BinOpInfo EmitBinOps(const BinaryOperator *E); 270 Value *EmitCompoundAssign(const CompoundAssignOperator *E, 271 Value *(ScalarExprEmitter::*F)(const BinOpInfo &)); 272 273 // Binary operators and binary compound assignment operators. 274#define HANDLEBINOP(OP) \ 275 Value *VisitBin ## OP(const BinaryOperator *E) { \ 276 return Emit ## OP(EmitBinOps(E)); \ 277 } \ 278 Value *VisitBin ## OP ## Assign(const CompoundAssignOperator *E) { \ 279 return EmitCompoundAssign(E, &ScalarExprEmitter::Emit ## OP); \ 280 } 281 HANDLEBINOP(Mul); 282 HANDLEBINOP(Div); 283 HANDLEBINOP(Rem); 284 HANDLEBINOP(Add); 285 HANDLEBINOP(Sub); 286 HANDLEBINOP(Shl); 287 HANDLEBINOP(Shr); 288 HANDLEBINOP(And); 289 HANDLEBINOP(Xor); 290 HANDLEBINOP(Or); 291#undef HANDLEBINOP 292 293 // Comparisons. 294 Value *EmitCompare(const BinaryOperator *E, unsigned UICmpOpc, 295 unsigned SICmpOpc, unsigned FCmpOpc); 296#define VISITCOMP(CODE, UI, SI, FP) \ 297 Value *VisitBin##CODE(const BinaryOperator *E) { \ 298 return EmitCompare(E, llvm::ICmpInst::UI, llvm::ICmpInst::SI, \ 299 llvm::FCmpInst::FP); } 300 VISITCOMP(LT, ICMP_ULT, ICMP_SLT, FCMP_OLT); 301 VISITCOMP(GT, ICMP_UGT, ICMP_SGT, FCMP_OGT); 302 VISITCOMP(LE, ICMP_ULE, ICMP_SLE, FCMP_OLE); 303 VISITCOMP(GE, ICMP_UGE, ICMP_SGE, FCMP_OGE); 304 VISITCOMP(EQ, ICMP_EQ , ICMP_EQ , FCMP_OEQ); 305 VISITCOMP(NE, ICMP_NE , ICMP_NE , FCMP_UNE); 306#undef VISITCOMP 307 308 Value *VisitBinAssign (const BinaryOperator *E); 309 310 Value *VisitBinLAnd (const BinaryOperator *E); 311 Value *VisitBinLOr (const BinaryOperator *E); 312 Value *VisitBinComma (const BinaryOperator *E); 313 314 // Other Operators. 315 Value *VisitConditionalOperator(const ConditionalOperator *CO); 316 Value *VisitChooseExpr(ChooseExpr *CE); 317 Value *VisitOverloadExpr(OverloadExpr *OE); 318 Value *VisitVAArgExpr(VAArgExpr *VE); 319 Value *VisitObjCStringLiteral(const ObjCStringLiteral *E) { 320 return CGF.EmitObjCStringLiteral(E); 321 } 322 Value *VisitObjCEncodeExpr(const ObjCEncodeExpr *E); 323}; 324} // end anonymous namespace. 325 326//===----------------------------------------------------------------------===// 327// Utilities 328//===----------------------------------------------------------------------===// 329 330/// EmitConversionToBool - Convert the specified expression value to a 331/// boolean (i1) truth value. This is equivalent to "Val != 0". 332Value *ScalarExprEmitter::EmitConversionToBool(Value *Src, QualType SrcType) { 333 assert(SrcType->isCanonical() && "EmitScalarConversion strips typedefs"); 334 335 if (SrcType->isRealFloatingType()) { 336 // Compare against 0.0 for fp scalars. 337 llvm::Value *Zero = llvm::Constant::getNullValue(Src->getType()); 338 return Builder.CreateFCmpUNE(Src, Zero, "tobool"); 339 } 340 341 assert((SrcType->isIntegerType() || isa<llvm::PointerType>(Src->getType())) && 342 "Unknown scalar type to convert"); 343 344 // Because of the type rules of C, we often end up computing a logical value, 345 // then zero extending it to int, then wanting it as a logical value again. 346 // Optimize this common case. 347 if (llvm::ZExtInst *ZI = dyn_cast<llvm::ZExtInst>(Src)) { 348 if (ZI->getOperand(0)->getType() == llvm::Type::Int1Ty) { 349 Value *Result = ZI->getOperand(0); 350 // If there aren't any more uses, zap the instruction to save space. 351 // Note that there can be more uses, for example if this 352 // is the result of an assignment. 353 if (ZI->use_empty()) 354 ZI->eraseFromParent(); 355 return Result; 356 } 357 } 358 359 // Compare against an integer or pointer null. 360 llvm::Value *Zero = llvm::Constant::getNullValue(Src->getType()); 361 return Builder.CreateICmpNE(Src, Zero, "tobool"); 362} 363 364/// EmitScalarConversion - Emit a conversion from the specified type to the 365/// specified destination type, both of which are LLVM scalar types. 366Value *ScalarExprEmitter::EmitScalarConversion(Value *Src, QualType SrcType, 367 QualType DstType) { 368 SrcType = CGF.getContext().getCanonicalType(SrcType); 369 DstType = CGF.getContext().getCanonicalType(DstType); 370 if (SrcType == DstType) return Src; 371 372 if (DstType->isVoidType()) return 0; 373 374 // Handle conversions to bool first, they are special: comparisons against 0. 375 if (DstType->isBooleanType()) 376 return EmitConversionToBool(Src, SrcType); 377 378 const llvm::Type *DstTy = ConvertType(DstType); 379 380 // Ignore conversions like int -> uint. 381 if (Src->getType() == DstTy) 382 return Src; 383 384 // Handle pointer conversions next: pointers can only be converted 385 // to/from other pointers and integers. Check for pointer types in 386 // terms of LLVM, as some native types (like Obj-C id) may map to a 387 // pointer type. 388 if (isa<llvm::PointerType>(DstTy)) { 389 // The source value may be an integer, or a pointer. 390 if (isa<llvm::PointerType>(Src->getType())) 391 return Builder.CreateBitCast(Src, DstTy, "conv"); 392 assert(SrcType->isIntegerType() && "Not ptr->ptr or int->ptr conversion?"); 393 return Builder.CreateIntToPtr(Src, DstTy, "conv"); 394 } 395 396 if (isa<llvm::PointerType>(Src->getType())) { 397 // Must be an ptr to int cast. 398 assert(isa<llvm::IntegerType>(DstTy) && "not ptr->int?"); 399 return Builder.CreatePtrToInt(Src, DstTy, "conv"); 400 } 401 402 // A scalar can be splatted to an extended vector of the same element type 403 if (DstType->isExtVectorType() && !isa<VectorType>(SrcType) && 404 cast<llvm::VectorType>(DstTy)->getElementType() == Src->getType()) 405 return CGF.EmitVector(&Src, DstType->getAsVectorType()->getNumElements(), 406 true); 407 408 // Allow bitcast from vector to integer/fp of the same size. 409 if (isa<llvm::VectorType>(Src->getType()) || 410 isa<llvm::VectorType>(DstTy)) 411 return Builder.CreateBitCast(Src, DstTy, "conv"); 412 413 // Finally, we have the arithmetic types: real int/float. 414 if (isa<llvm::IntegerType>(Src->getType())) { 415 bool InputSigned = SrcType->isSignedIntegerType(); 416 if (isa<llvm::IntegerType>(DstTy)) 417 return Builder.CreateIntCast(Src, DstTy, InputSigned, "conv"); 418 else if (InputSigned) 419 return Builder.CreateSIToFP(Src, DstTy, "conv"); 420 else 421 return Builder.CreateUIToFP(Src, DstTy, "conv"); 422 } 423 424 assert(Src->getType()->isFloatingPoint() && "Unknown real conversion"); 425 if (isa<llvm::IntegerType>(DstTy)) { 426 if (DstType->isSignedIntegerType()) 427 return Builder.CreateFPToSI(Src, DstTy, "conv"); 428 else 429 return Builder.CreateFPToUI(Src, DstTy, "conv"); 430 } 431 432 assert(DstTy->isFloatingPoint() && "Unknown real conversion"); 433 if (DstTy->getTypeID() < Src->getType()->getTypeID()) 434 return Builder.CreateFPTrunc(Src, DstTy, "conv"); 435 else 436 return Builder.CreateFPExt(Src, DstTy, "conv"); 437} 438 439/// EmitComplexToScalarConversion - Emit a conversion from the specified 440/// complex type to the specified destination type, where the destination 441/// type is an LLVM scalar type. 442Value *ScalarExprEmitter:: 443EmitComplexToScalarConversion(CodeGenFunction::ComplexPairTy Src, 444 QualType SrcTy, QualType DstTy) { 445 // Get the source element type. 446 SrcTy = SrcTy->getAsComplexType()->getElementType(); 447 448 // Handle conversions to bool first, they are special: comparisons against 0. 449 if (DstTy->isBooleanType()) { 450 // Complex != 0 -> (Real != 0) | (Imag != 0) 451 Src.first = EmitScalarConversion(Src.first, SrcTy, DstTy); 452 Src.second = EmitScalarConversion(Src.second, SrcTy, DstTy); 453 return Builder.CreateOr(Src.first, Src.second, "tobool"); 454 } 455 456 // C99 6.3.1.7p2: "When a value of complex type is converted to a real type, 457 // the imaginary part of the complex value is discarded and the value of the 458 // real part is converted according to the conversion rules for the 459 // corresponding real type. 460 return EmitScalarConversion(Src.first, SrcTy, DstTy); 461} 462 463 464//===----------------------------------------------------------------------===// 465// Visitor Methods 466//===----------------------------------------------------------------------===// 467 468Value *ScalarExprEmitter::VisitExpr(Expr *E) { 469 CGF.ErrorUnsupported(E, "scalar expression"); 470 if (E->getType()->isVoidType()) 471 return 0; 472 return llvm::UndefValue::get(CGF.ConvertType(E->getType())); 473} 474 475Value *ScalarExprEmitter::VisitShuffleVectorExpr(ShuffleVectorExpr *E) { 476 llvm::SmallVector<llvm::Constant*, 32> indices; 477 for (unsigned i = 2; i < E->getNumSubExprs(); i++) { 478 indices.push_back(cast<llvm::Constant>(CGF.EmitScalarExpr(E->getExpr(i)))); 479 } 480 Value* V1 = CGF.EmitScalarExpr(E->getExpr(0)); 481 Value* V2 = CGF.EmitScalarExpr(E->getExpr(1)); 482 Value* SV = llvm::ConstantVector::get(indices.begin(), indices.size()); 483 return Builder.CreateShuffleVector(V1, V2, SV, "shuffle"); 484} 485 486Value *ScalarExprEmitter::VisitArraySubscriptExpr(ArraySubscriptExpr *E) { 487 // Emit subscript expressions in rvalue context's. For most cases, this just 488 // loads the lvalue formed by the subscript expr. However, we have to be 489 // careful, because the base of a vector subscript is occasionally an rvalue, 490 // so we can't get it as an lvalue. 491 if (!E->getBase()->getType()->isVectorType()) 492 return EmitLoadOfLValue(E); 493 494 // Handle the vector case. The base must be a vector, the index must be an 495 // integer value. 496 Value *Base = Visit(E->getBase()); 497 Value *Idx = Visit(E->getIdx()); 498 499 // FIXME: Convert Idx to i32 type. 500 return Builder.CreateExtractElement(Base, Idx, "vecext"); 501} 502 503/// VisitImplicitCastExpr - Implicit casts are the same as normal casts, but 504/// also handle things like function to pointer-to-function decay, and array to 505/// pointer decay. 506Value *ScalarExprEmitter::VisitImplicitCastExpr(const ImplicitCastExpr *E) { 507 const Expr *Op = E->getSubExpr(); 508 509 // If this is due to array->pointer conversion, emit the array expression as 510 // an l-value. 511 if (Op->getType()->isArrayType()) { 512 // FIXME: For now we assume that all source arrays map to LLVM arrays. This 513 // will not true when we add support for VLAs. 514 Value *V = EmitLValue(Op).getAddress(); // Bitfields can't be arrays. 515 516 if (!(isa<llvm::PointerType>(V->getType()) && 517 isa<llvm::ArrayType>(cast<llvm::PointerType>(V->getType()) 518 ->getElementType()))) { 519 CGF.ErrorUnsupported(E, "variable-length array cast", true); 520 if (E->getType()->isVoidType()) 521 return 0; 522 return llvm::UndefValue::get(CGF.ConvertType(E->getType())); 523 } 524 V = Builder.CreateStructGEP(V, 0, "arraydecay"); 525 526 // The resultant pointer type can be implicitly casted to other pointer 527 // types as well (e.g. void*) and can be implicitly converted to integer. 528 const llvm::Type *DestTy = ConvertType(E->getType()); 529 if (V->getType() != DestTy) { 530 if (isa<llvm::PointerType>(DestTy)) 531 V = Builder.CreateBitCast(V, DestTy, "ptrconv"); 532 else { 533 assert(isa<llvm::IntegerType>(DestTy) && "Unknown array decay"); 534 V = Builder.CreatePtrToInt(V, DestTy, "ptrconv"); 535 } 536 } 537 return V; 538 539 } else if (E->getType()->isReferenceType()) { 540 return EmitLValue(Op).getAddress(); 541 } 542 543 return EmitCastExpr(Op, E->getType()); 544} 545 546 547// VisitCastExpr - Emit code for an explicit or implicit cast. Implicit casts 548// have to handle a more broad range of conversions than explicit casts, as they 549// handle things like function to ptr-to-function decay etc. 550Value *ScalarExprEmitter::EmitCastExpr(const Expr *E, QualType DestTy) { 551 // Handle cases where the source is an non-complex type. 552 553 if (!CGF.hasAggregateLLVMType(E->getType())) { 554 Value *Src = Visit(const_cast<Expr*>(E)); 555 556 // Use EmitScalarConversion to perform the conversion. 557 return EmitScalarConversion(Src, E->getType(), DestTy); 558 } 559 560 if (E->getType()->isAnyComplexType()) { 561 // Handle cases where the source is a complex type. 562 return EmitComplexToScalarConversion(CGF.EmitComplexExpr(E), E->getType(), 563 DestTy); 564 } 565 566 // Okay, this is a cast from an aggregate. It must be a cast to void. Just 567 // evaluate the result and return. 568 CGF.EmitAggExpr(E, 0, false); 569 return 0; 570} 571 572Value *ScalarExprEmitter::VisitStmtExpr(const StmtExpr *E) { 573 return CGF.EmitCompoundStmt(*E->getSubStmt(), 574 !E->getType()->isVoidType()).getScalarVal(); 575} 576 577 578//===----------------------------------------------------------------------===// 579// Unary Operators 580//===----------------------------------------------------------------------===// 581 582Value *ScalarExprEmitter::VisitPrePostIncDec(const UnaryOperator *E, 583 bool isInc, bool isPre) { 584 LValue LV = EmitLValue(E->getSubExpr()); 585 // FIXME: Handle volatile! 586 Value *InVal = CGF.EmitLoadOfLValue(LV, // false 587 E->getSubExpr()->getType()).getScalarVal(); 588 589 int AmountVal = isInc ? 1 : -1; 590 591 Value *NextVal; 592 if (isa<llvm::PointerType>(InVal->getType())) { 593 // FIXME: This isn't right for VLAs. 594 NextVal = llvm::ConstantInt::get(llvm::Type::Int32Ty, AmountVal); 595 NextVal = Builder.CreateGEP(InVal, NextVal, "ptrincdec"); 596 } else { 597 // Add the inc/dec to the real part. 598 if (isa<llvm::IntegerType>(InVal->getType())) 599 NextVal = llvm::ConstantInt::get(InVal->getType(), AmountVal); 600 else if (InVal->getType() == llvm::Type::FloatTy) 601 NextVal = 602 llvm::ConstantFP::get(llvm::APFloat(static_cast<float>(AmountVal))); 603 else if (InVal->getType() == llvm::Type::DoubleTy) 604 NextVal = 605 llvm::ConstantFP::get(llvm::APFloat(static_cast<double>(AmountVal))); 606 else { 607 llvm::APFloat F(static_cast<float>(AmountVal)); 608 bool ignored; 609 F.convert(CGF.Target.getLongDoubleFormat(), llvm::APFloat::rmTowardZero, 610 &ignored); 611 NextVal = llvm::ConstantFP::get(F); 612 } 613 NextVal = Builder.CreateAdd(InVal, NextVal, isInc ? "inc" : "dec"); 614 } 615 616 // Store the updated result through the lvalue. 617 CGF.EmitStoreThroughLValue(RValue::get(NextVal), LV, 618 E->getSubExpr()->getType()); 619 620 // If this is a postinc, return the value read from memory, otherwise use the 621 // updated value. 622 return isPre ? NextVal : InVal; 623} 624 625 626Value *ScalarExprEmitter::VisitUnaryMinus(const UnaryOperator *E) { 627 Value *Op = Visit(E->getSubExpr()); 628 return Builder.CreateNeg(Op, "neg"); 629} 630 631Value *ScalarExprEmitter::VisitUnaryNot(const UnaryOperator *E) { 632 Value *Op = Visit(E->getSubExpr()); 633 return Builder.CreateNot(Op, "neg"); 634} 635 636Value *ScalarExprEmitter::VisitUnaryLNot(const UnaryOperator *E) { 637 // Compare operand to zero. 638 Value *BoolVal = CGF.EvaluateExprAsBool(E->getSubExpr()); 639 640 // Invert value. 641 // TODO: Could dynamically modify easy computations here. For example, if 642 // the operand is an icmp ne, turn into icmp eq. 643 BoolVal = Builder.CreateNot(BoolVal, "lnot"); 644 645 // ZExt result to int. 646 return Builder.CreateZExt(BoolVal, CGF.LLVMIntTy, "lnot.ext"); 647} 648 649/// EmitSizeAlignOf - Return the size or alignment of the 'TypeToSize' type as 650/// an integer (RetType). 651Value *ScalarExprEmitter::EmitSizeAlignOf(QualType TypeToSize, 652 QualType RetType,bool isSizeOf){ 653 assert(RetType->isIntegerType() && "Result type must be an integer!"); 654 uint32_t ResultWidth = 655 static_cast<uint32_t>(CGF.getContext().getTypeSize(RetType)); 656 657 // sizeof(void) and __alignof__(void) = 1 as a gcc extension. Also 658 // for function types. 659 // FIXME: what is alignof a function type in gcc? 660 if (TypeToSize->isVoidType() || TypeToSize->isFunctionType()) 661 return llvm::ConstantInt::get(llvm::APInt(ResultWidth, 1)); 662 663 /// FIXME: This doesn't handle VLAs yet! 664 std::pair<uint64_t, unsigned> Info = CGF.getContext().getTypeInfo(TypeToSize); 665 666 uint64_t Val = isSizeOf ? Info.first : Info.second; 667 Val /= 8; // Return size in bytes, not bits. 668 669 return llvm::ConstantInt::get(llvm::APInt(ResultWidth, Val)); 670} 671 672Value *ScalarExprEmitter::VisitUnaryReal(const UnaryOperator *E) { 673 Expr *Op = E->getSubExpr(); 674 if (Op->getType()->isAnyComplexType()) 675 return CGF.EmitComplexExpr(Op).first; 676 return Visit(Op); 677} 678Value *ScalarExprEmitter::VisitUnaryImag(const UnaryOperator *E) { 679 Expr *Op = E->getSubExpr(); 680 if (Op->getType()->isAnyComplexType()) 681 return CGF.EmitComplexExpr(Op).second; 682 683 // __imag on a scalar returns zero. Emit it the subexpr to ensure side 684 // effects are evaluated. 685 CGF.EmitScalarExpr(Op); 686 return llvm::Constant::getNullValue(ConvertType(E->getType())); 687} 688 689Value *ScalarExprEmitter::VisitUnaryOffsetOf(const UnaryOperator *E) 690{ 691 int64_t Val = E->evaluateOffsetOf(CGF.getContext()); 692 693 assert(E->getType()->isIntegerType() && "Result type must be an integer!"); 694 695 uint32_t ResultWidth = 696 static_cast<uint32_t>(CGF.getContext().getTypeSize(E->getType())); 697 return llvm::ConstantInt::get(llvm::APInt(ResultWidth, Val)); 698} 699 700//===----------------------------------------------------------------------===// 701// Binary Operators 702//===----------------------------------------------------------------------===// 703 704BinOpInfo ScalarExprEmitter::EmitBinOps(const BinaryOperator *E) { 705 BinOpInfo Result; 706 Result.LHS = Visit(E->getLHS()); 707 Result.RHS = Visit(E->getRHS()); 708 Result.Ty = E->getType(); 709 Result.E = E; 710 return Result; 711} 712 713Value *ScalarExprEmitter::EmitCompoundAssign(const CompoundAssignOperator *E, 714 Value *(ScalarExprEmitter::*Func)(const BinOpInfo &)) { 715 QualType LHSTy = E->getLHS()->getType(), RHSTy = E->getRHS()->getType(); 716 717 BinOpInfo OpInfo; 718 719 // Load the LHS and RHS operands. 720 LValue LHSLV = EmitLValue(E->getLHS()); 721 OpInfo.LHS = EmitLoadOfLValue(LHSLV, LHSTy); 722 723 // Determine the computation type. If the RHS is complex, then this is one of 724 // the add/sub/mul/div operators. All of these operators can be computed in 725 // with just their real component even though the computation domain really is 726 // complex. 727 QualType ComputeType = E->getComputationType(); 728 729 // If the computation type is complex, then the RHS is complex. Emit the RHS. 730 if (const ComplexType *CT = ComputeType->getAsComplexType()) { 731 ComputeType = CT->getElementType(); 732 733 // Emit the RHS, only keeping the real component. 734 OpInfo.RHS = CGF.EmitComplexExpr(E->getRHS()).first; 735 RHSTy = RHSTy->getAsComplexType()->getElementType(); 736 } else { 737 // Otherwise the RHS is a simple scalar value. 738 OpInfo.RHS = Visit(E->getRHS()); 739 } 740 741 QualType LComputeTy, RComputeTy, ResultTy; 742 743 // Compound assignment does not contain enough information about all 744 // the types involved for pointer arithmetic cases. Figure it out 745 // here for now. 746 if (E->getLHS()->getType()->isPointerType()) { 747 // Pointer arithmetic cases: ptr +=,-= int and ptr -= ptr, 748 assert((E->getOpcode() == BinaryOperator::AddAssign || 749 E->getOpcode() == BinaryOperator::SubAssign) && 750 "Invalid compound assignment operator on pointer type."); 751 LComputeTy = E->getLHS()->getType(); 752 753 if (E->getRHS()->getType()->isPointerType()) { 754 // Degenerate case of (ptr -= ptr) allowed by GCC implicit cast 755 // extension, the conversion from the pointer difference back to 756 // the LHS type is handled at the end. 757 assert(E->getOpcode() == BinaryOperator::SubAssign && 758 "Invalid compound assignment operator on pointer type."); 759 RComputeTy = E->getLHS()->getType(); 760 ResultTy = CGF.getContext().getPointerDiffType(); 761 } else { 762 RComputeTy = E->getRHS()->getType(); 763 ResultTy = LComputeTy; 764 } 765 } else if (E->getRHS()->getType()->isPointerType()) { 766 // Degenerate case of (int += ptr) allowed by GCC implicit cast 767 // extension. 768 assert(E->getOpcode() == BinaryOperator::AddAssign && 769 "Invalid compound assignment operator on pointer type."); 770 LComputeTy = E->getLHS()->getType(); 771 RComputeTy = E->getRHS()->getType(); 772 ResultTy = RComputeTy; 773 } else { 774 LComputeTy = RComputeTy = ResultTy = ComputeType; 775 } 776 777 // Convert the LHS/RHS values to the computation type. 778 OpInfo.LHS = EmitScalarConversion(OpInfo.LHS, LHSTy, LComputeTy); 779 OpInfo.RHS = EmitScalarConversion(OpInfo.RHS, RHSTy, RComputeTy); 780 OpInfo.Ty = ResultTy; 781 OpInfo.E = E; 782 783 // Expand the binary operator. 784 Value *Result = (this->*Func)(OpInfo); 785 786 // Convert the result back to the LHS type. 787 Result = EmitScalarConversion(Result, ResultTy, LHSTy); 788 789 // Store the result value into the LHS lvalue. 790 CGF.EmitStoreThroughLValue(RValue::get(Result), LHSLV, LHSTy); 791 792 // For bitfields, we need the value in the bitfield. Note that 793 // property references do not reload their value (even though the 794 // setter may have changed it). 795 // FIXME: This adds an extra bitfield load 796 if (LHSLV.isBitfield()) 797 Result = EmitLoadOfLValue(LHSLV, LHSTy); 798 return Result; 799} 800 801 802Value *ScalarExprEmitter::EmitDiv(const BinOpInfo &Ops) { 803 if (Ops.LHS->getType()->isFPOrFPVector()) 804 return Builder.CreateFDiv(Ops.LHS, Ops.RHS, "div"); 805 else if (Ops.Ty->isUnsignedIntegerType()) 806 return Builder.CreateUDiv(Ops.LHS, Ops.RHS, "div"); 807 else 808 return Builder.CreateSDiv(Ops.LHS, Ops.RHS, "div"); 809} 810 811Value *ScalarExprEmitter::EmitRem(const BinOpInfo &Ops) { 812 // Rem in C can't be a floating point type: C99 6.5.5p2. 813 if (Ops.Ty->isUnsignedIntegerType()) 814 return Builder.CreateURem(Ops.LHS, Ops.RHS, "rem"); 815 else 816 return Builder.CreateSRem(Ops.LHS, Ops.RHS, "rem"); 817} 818 819 820Value *ScalarExprEmitter::EmitAdd(const BinOpInfo &Ops) { 821 if (!Ops.Ty->isPointerType()) 822 return Builder.CreateAdd(Ops.LHS, Ops.RHS, "add"); 823 824 // FIXME: What about a pointer to a VLA? 825 Value *Ptr, *Idx; 826 Expr *IdxExp; 827 if (isa<llvm::PointerType>(Ops.LHS->getType())) { // pointer + int 828 Ptr = Ops.LHS; 829 Idx = Ops.RHS; 830 IdxExp = Ops.E->getRHS(); 831 } else { // int + pointer 832 Ptr = Ops.RHS; 833 Idx = Ops.LHS; 834 IdxExp = Ops.E->getLHS(); 835 } 836 837 unsigned Width = cast<llvm::IntegerType>(Idx->getType())->getBitWidth(); 838 if (Width < CGF.LLVMPointerWidth) { 839 // Zero or sign extend the pointer value based on whether the index is 840 // signed or not. 841 const llvm::Type *IdxType = llvm::IntegerType::get(CGF.LLVMPointerWidth); 842 if (IdxExp->getType()->isSignedIntegerType()) 843 Idx = Builder.CreateSExt(Idx, IdxType, "idx.ext"); 844 else 845 Idx = Builder.CreateZExt(Idx, IdxType, "idx.ext"); 846 } 847 848 return Builder.CreateGEP(Ptr, Idx, "add.ptr"); 849} 850 851Value *ScalarExprEmitter::EmitSub(const BinOpInfo &Ops) { 852 if (!isa<llvm::PointerType>(Ops.LHS->getType())) 853 return Builder.CreateSub(Ops.LHS, Ops.RHS, "sub"); 854 855 if (!isa<llvm::PointerType>(Ops.RHS->getType())) { 856 // pointer - int 857 Value *Idx = Ops.RHS; 858 unsigned Width = cast<llvm::IntegerType>(Idx->getType())->getBitWidth(); 859 if (Width < CGF.LLVMPointerWidth) { 860 // Zero or sign extend the pointer value based on whether the index is 861 // signed or not. 862 const llvm::Type *IdxType = llvm::IntegerType::get(CGF.LLVMPointerWidth); 863 if (Ops.E->getRHS()->getType()->isSignedIntegerType()) 864 Idx = Builder.CreateSExt(Idx, IdxType, "idx.ext"); 865 else 866 Idx = Builder.CreateZExt(Idx, IdxType, "idx.ext"); 867 } 868 Idx = Builder.CreateNeg(Idx, "sub.ptr.neg"); 869 870 // FIXME: The pointer could point to a VLA. 871 // The GNU void* - int case is automatically handled here because 872 // our LLVM type for void* is i8*. 873 return Builder.CreateGEP(Ops.LHS, Idx, "sub.ptr"); 874 } else { 875 // pointer - pointer 876 Value *LHS = Ops.LHS; 877 Value *RHS = Ops.RHS; 878 879 const QualType LHSType = Ops.E->getLHS()->getType(); 880 const QualType LHSElementType = LHSType->getAsPointerType()->getPointeeType(); 881 uint64_t ElementSize; 882 883 // Handle GCC extension for pointer arithmetic on void* types. 884 if (LHSElementType->isVoidType()) { 885 ElementSize = 1; 886 } else { 887 ElementSize = CGF.getContext().getTypeSize(LHSElementType) / 8; 888 } 889 890 const llvm::Type *ResultType = ConvertType(Ops.Ty); 891 LHS = Builder.CreatePtrToInt(LHS, ResultType, "sub.ptr.lhs.cast"); 892 RHS = Builder.CreatePtrToInt(RHS, ResultType, "sub.ptr.rhs.cast"); 893 Value *BytesBetween = Builder.CreateSub(LHS, RHS, "sub.ptr.sub"); 894 895 // HACK: LLVM doesn't have an divide instruction that 'knows' there is no 896 // remainder. As such, we handle common power-of-two cases here to generate 897 // better code. See PR2247. 898 if (llvm::isPowerOf2_64(ElementSize)) { 899 Value *ShAmt = 900 llvm::ConstantInt::get(ResultType, llvm::Log2_64(ElementSize)); 901 return Builder.CreateAShr(BytesBetween, ShAmt, "sub.ptr.shr"); 902 } 903 904 // Otherwise, do a full sdiv. 905 Value *BytesPerElt = llvm::ConstantInt::get(ResultType, ElementSize); 906 return Builder.CreateSDiv(BytesBetween, BytesPerElt, "sub.ptr.div"); 907 } 908} 909 910Value *ScalarExprEmitter::EmitShl(const BinOpInfo &Ops) { 911 // LLVM requires the LHS and RHS to be the same type: promote or truncate the 912 // RHS to the same size as the LHS. 913 Value *RHS = Ops.RHS; 914 if (Ops.LHS->getType() != RHS->getType()) 915 RHS = Builder.CreateIntCast(RHS, Ops.LHS->getType(), false, "sh_prom"); 916 917 return Builder.CreateShl(Ops.LHS, RHS, "shl"); 918} 919 920Value *ScalarExprEmitter::EmitShr(const BinOpInfo &Ops) { 921 // LLVM requires the LHS and RHS to be the same type: promote or truncate the 922 // RHS to the same size as the LHS. 923 Value *RHS = Ops.RHS; 924 if (Ops.LHS->getType() != RHS->getType()) 925 RHS = Builder.CreateIntCast(RHS, Ops.LHS->getType(), false, "sh_prom"); 926 927 if (Ops.Ty->isUnsignedIntegerType()) 928 return Builder.CreateLShr(Ops.LHS, RHS, "shr"); 929 return Builder.CreateAShr(Ops.LHS, RHS, "shr"); 930} 931 932Value *ScalarExprEmitter::EmitCompare(const BinaryOperator *E,unsigned UICmpOpc, 933 unsigned SICmpOpc, unsigned FCmpOpc) { 934 Value *Result; 935 QualType LHSTy = E->getLHS()->getType(); 936 if (!LHSTy->isAnyComplexType() && !LHSTy->isVectorType()) { 937 Value *LHS = Visit(E->getLHS()); 938 Value *RHS = Visit(E->getRHS()); 939 940 if (LHS->getType()->isFloatingPoint()) { 941 Result = Builder.CreateFCmp((llvm::CmpInst::Predicate)FCmpOpc, 942 LHS, RHS, "cmp"); 943 } else if (LHSTy->isSignedIntegerType()) { 944 Result = Builder.CreateICmp((llvm::ICmpInst::Predicate)SICmpOpc, 945 LHS, RHS, "cmp"); 946 } else { 947 // Unsigned integers and pointers. 948 Result = Builder.CreateICmp((llvm::ICmpInst::Predicate)UICmpOpc, 949 LHS, RHS, "cmp"); 950 } 951 } else if (LHSTy->isVectorType()) { 952 Value *LHS = Visit(E->getLHS()); 953 Value *RHS = Visit(E->getRHS()); 954 955 if (LHS->getType()->isFPOrFPVector()) { 956 Result = Builder.CreateVFCmp((llvm::CmpInst::Predicate)FCmpOpc, 957 LHS, RHS, "cmp"); 958 } else if (LHSTy->isUnsignedIntegerType()) { 959 Result = Builder.CreateVICmp((llvm::CmpInst::Predicate)UICmpOpc, 960 LHS, RHS, "cmp"); 961 } else { 962 // Signed integers and pointers. 963 Result = Builder.CreateVICmp((llvm::CmpInst::Predicate)SICmpOpc, 964 LHS, RHS, "cmp"); 965 } 966 return Result; 967 } else { 968 // Complex Comparison: can only be an equality comparison. 969 CodeGenFunction::ComplexPairTy LHS = CGF.EmitComplexExpr(E->getLHS()); 970 CodeGenFunction::ComplexPairTy RHS = CGF.EmitComplexExpr(E->getRHS()); 971 972 QualType CETy = LHSTy->getAsComplexType()->getElementType(); 973 974 Value *ResultR, *ResultI; 975 if (CETy->isRealFloatingType()) { 976 ResultR = Builder.CreateFCmp((llvm::FCmpInst::Predicate)FCmpOpc, 977 LHS.first, RHS.first, "cmp.r"); 978 ResultI = Builder.CreateFCmp((llvm::FCmpInst::Predicate)FCmpOpc, 979 LHS.second, RHS.second, "cmp.i"); 980 } else { 981 // Complex comparisons can only be equality comparisons. As such, signed 982 // and unsigned opcodes are the same. 983 ResultR = Builder.CreateICmp((llvm::ICmpInst::Predicate)UICmpOpc, 984 LHS.first, RHS.first, "cmp.r"); 985 ResultI = Builder.CreateICmp((llvm::ICmpInst::Predicate)UICmpOpc, 986 LHS.second, RHS.second, "cmp.i"); 987 } 988 989 if (E->getOpcode() == BinaryOperator::EQ) { 990 Result = Builder.CreateAnd(ResultR, ResultI, "and.ri"); 991 } else { 992 assert(E->getOpcode() == BinaryOperator::NE && 993 "Complex comparison other than == or != ?"); 994 Result = Builder.CreateOr(ResultR, ResultI, "or.ri"); 995 } 996 } 997 998 // ZExt result to int. 999 return Builder.CreateZExt(Result, CGF.LLVMIntTy, "cmp.ext"); 1000} 1001 1002Value *ScalarExprEmitter::VisitBinAssign(const BinaryOperator *E) { 1003 LValue LHS = EmitLValue(E->getLHS()); 1004 Value *RHS = Visit(E->getRHS()); 1005 1006 // Store the value into the LHS. 1007 // FIXME: Volatility! 1008 CGF.EmitStoreThroughLValue(RValue::get(RHS), LHS, E->getType()); 1009 1010 // For bitfields, we need the value in the bitfield. Note that 1011 // property references do not reload their value (even though the 1012 // setter may have changed it). 1013 // FIXME: This adds an extra bitfield load 1014 if (LHS.isBitfield()) 1015 return EmitLoadOfLValue(LHS, E->getLHS()->getType()); 1016 1017 // Return the RHS. 1018 return RHS; 1019} 1020 1021Value *ScalarExprEmitter::VisitBinLAnd(const BinaryOperator *E) { 1022 Value *LHSCond = CGF.EvaluateExprAsBool(E->getLHS()); 1023 1024 llvm::BasicBlock *ContBlock = llvm::BasicBlock::Create("land_cont"); 1025 llvm::BasicBlock *RHSBlock = llvm::BasicBlock::Create("land_rhs"); 1026 1027 llvm::BasicBlock *OrigBlock = Builder.GetInsertBlock(); 1028 Builder.CreateCondBr(LHSCond, RHSBlock, ContBlock); 1029 1030 CGF.EmitBlock(RHSBlock); 1031 Value *RHSCond = CGF.EvaluateExprAsBool(E->getRHS()); 1032 1033 // Reaquire the RHS block, as there may be subblocks inserted. 1034 RHSBlock = Builder.GetInsertBlock(); 1035 CGF.EmitBlock(ContBlock); 1036 1037 // Create a PHI node. If we just evaluted the LHS condition, the result is 1038 // false. If we evaluated both, the result is the RHS condition. 1039 llvm::PHINode *PN = Builder.CreatePHI(llvm::Type::Int1Ty, "land"); 1040 PN->reserveOperandSpace(2); 1041 PN->addIncoming(llvm::ConstantInt::getFalse(), OrigBlock); 1042 PN->addIncoming(RHSCond, RHSBlock); 1043 1044 // ZExt result to int. 1045 return Builder.CreateZExt(PN, CGF.LLVMIntTy, "land.ext"); 1046} 1047 1048Value *ScalarExprEmitter::VisitBinLOr(const BinaryOperator *E) { 1049 Value *LHSCond = CGF.EvaluateExprAsBool(E->getLHS()); 1050 1051 llvm::BasicBlock *ContBlock = llvm::BasicBlock::Create("lor_cont"); 1052 llvm::BasicBlock *RHSBlock = llvm::BasicBlock::Create("lor_rhs"); 1053 1054 llvm::BasicBlock *OrigBlock = Builder.GetInsertBlock(); 1055 Builder.CreateCondBr(LHSCond, ContBlock, RHSBlock); 1056 1057 CGF.EmitBlock(RHSBlock); 1058 Value *RHSCond = CGF.EvaluateExprAsBool(E->getRHS()); 1059 1060 // Reaquire the RHS block, as there may be subblocks inserted. 1061 RHSBlock = Builder.GetInsertBlock(); 1062 CGF.EmitBlock(ContBlock); 1063 1064 // Create a PHI node. If we just evaluted the LHS condition, the result is 1065 // true. If we evaluated both, the result is the RHS condition. 1066 llvm::PHINode *PN = Builder.CreatePHI(llvm::Type::Int1Ty, "lor"); 1067 PN->reserveOperandSpace(2); 1068 PN->addIncoming(llvm::ConstantInt::getTrue(), OrigBlock); 1069 PN->addIncoming(RHSCond, RHSBlock); 1070 1071 // ZExt result to int. 1072 return Builder.CreateZExt(PN, CGF.LLVMIntTy, "lor.ext"); 1073} 1074 1075Value *ScalarExprEmitter::VisitBinComma(const BinaryOperator *E) { 1076 CGF.EmitStmt(E->getLHS()); 1077 return Visit(E->getRHS()); 1078} 1079 1080//===----------------------------------------------------------------------===// 1081// Other Operators 1082//===----------------------------------------------------------------------===// 1083 1084Value *ScalarExprEmitter:: 1085VisitConditionalOperator(const ConditionalOperator *E) { 1086 llvm::BasicBlock *LHSBlock = llvm::BasicBlock::Create("cond.?"); 1087 llvm::BasicBlock *RHSBlock = llvm::BasicBlock::Create("cond.:"); 1088 llvm::BasicBlock *ContBlock = llvm::BasicBlock::Create("cond.cont"); 1089 1090 // Evaluate the conditional, then convert it to bool. We do this explicitly 1091 // because we need the unconverted value if this is a GNU ?: expression with 1092 // missing middle value. 1093 Value *CondVal = CGF.EmitScalarExpr(E->getCond()); 1094 Value *CondBoolVal =CGF.EmitScalarConversion(CondVal, E->getCond()->getType(), 1095 CGF.getContext().BoolTy); 1096 Builder.CreateCondBr(CondBoolVal, LHSBlock, RHSBlock); 1097 1098 CGF.EmitBlock(LHSBlock); 1099 1100 // Handle the GNU extension for missing LHS. 1101 Value *LHS; 1102 if (E->getLHS()) 1103 LHS = Visit(E->getLHS()); 1104 else // Perform promotions, to handle cases like "short ?: int" 1105 LHS = EmitScalarConversion(CondVal, E->getCond()->getType(), E->getType()); 1106 1107 Builder.CreateBr(ContBlock); 1108 LHSBlock = Builder.GetInsertBlock(); 1109 1110 CGF.EmitBlock(RHSBlock); 1111 1112 Value *RHS = Visit(E->getRHS()); 1113 Builder.CreateBr(ContBlock); 1114 RHSBlock = Builder.GetInsertBlock(); 1115 1116 CGF.EmitBlock(ContBlock); 1117 1118 if (!LHS || !RHS) { 1119 assert(E->getType()->isVoidType() && "Non-void value should have a value"); 1120 return 0; 1121 } 1122 1123 // Create a PHI node for the real part. 1124 llvm::PHINode *PN = Builder.CreatePHI(LHS->getType(), "cond"); 1125 PN->reserveOperandSpace(2); 1126 PN->addIncoming(LHS, LHSBlock); 1127 PN->addIncoming(RHS, RHSBlock); 1128 return PN; 1129} 1130 1131Value *ScalarExprEmitter::VisitChooseExpr(ChooseExpr *E) { 1132 // Emit the LHS or RHS as appropriate. 1133 return 1134 Visit(E->isConditionTrue(CGF.getContext()) ? E->getLHS() : E->getRHS()); 1135} 1136 1137Value *ScalarExprEmitter::VisitOverloadExpr(OverloadExpr *E) { 1138 return CGF.EmitCallExpr(E->getFn(), E->arg_begin(), 1139 E->arg_end(CGF.getContext())).getScalarVal(); 1140} 1141 1142Value *ScalarExprEmitter::VisitVAArgExpr(VAArgExpr *VE) { 1143 llvm::Value *ArgValue = EmitLValue(VE->getSubExpr()).getAddress(); 1144 1145 llvm::Value *V = Builder.CreateVAArg(ArgValue, ConvertType(VE->getType())); 1146 return V; 1147} 1148 1149Value *ScalarExprEmitter::VisitObjCEncodeExpr(const ObjCEncodeExpr *E) { 1150 std::string str; 1151 llvm::SmallVector<const RecordType *, 8> EncodingRecordTypes; 1152 CGF.getContext().getObjCEncodingForType(E->getEncodedType(), str, 1153 EncodingRecordTypes); 1154 1155 llvm::Constant *C = llvm::ConstantArray::get(str); 1156 C = new llvm::GlobalVariable(C->getType(), true, 1157 llvm::GlobalValue::InternalLinkage, 1158 C, ".str", &CGF.CGM.getModule()); 1159 llvm::Constant *Zero = llvm::Constant::getNullValue(llvm::Type::Int32Ty); 1160 llvm::Constant *Zeros[] = { Zero, Zero }; 1161 C = llvm::ConstantExpr::getGetElementPtr(C, Zeros, 2); 1162 1163 return C; 1164} 1165 1166//===----------------------------------------------------------------------===// 1167// Entry Point into this File 1168//===----------------------------------------------------------------------===// 1169 1170/// EmitComplexExpr - Emit the computation of the specified expression of 1171/// complex type, ignoring the result. 1172Value *CodeGenFunction::EmitScalarExpr(const Expr *E) { 1173 assert(E && !hasAggregateLLVMType(E->getType()) && 1174 "Invalid scalar expression to emit"); 1175 1176 return ScalarExprEmitter(*this).Visit(const_cast<Expr*>(E)); 1177} 1178 1179/// EmitScalarConversion - Emit a conversion from the specified type to the 1180/// specified destination type, both of which are LLVM scalar types. 1181Value *CodeGenFunction::EmitScalarConversion(Value *Src, QualType SrcTy, 1182 QualType DstTy) { 1183 assert(!hasAggregateLLVMType(SrcTy) && !hasAggregateLLVMType(DstTy) && 1184 "Invalid scalar expression to emit"); 1185 return ScalarExprEmitter(*this).EmitScalarConversion(Src, SrcTy, DstTy); 1186} 1187 1188/// EmitComplexToScalarConversion - Emit a conversion from the specified 1189/// complex type to the specified destination type, where the destination 1190/// type is an LLVM scalar type. 1191Value *CodeGenFunction::EmitComplexToScalarConversion(ComplexPairTy Src, 1192 QualType SrcTy, 1193 QualType DstTy) { 1194 assert(SrcTy->isAnyComplexType() && !hasAggregateLLVMType(DstTy) && 1195 "Invalid complex -> scalar conversion"); 1196 return ScalarExprEmitter(*this).EmitComplexToScalarConversion(Src, SrcTy, 1197 DstTy); 1198} 1199 1200Value *CodeGenFunction::EmitShuffleVector(Value* V1, Value *V2, ...) { 1201 assert(V1->getType() == V2->getType() && 1202 "Vector operands must be of the same type"); 1203 unsigned NumElements = 1204 cast<llvm::VectorType>(V1->getType())->getNumElements(); 1205 1206 va_list va; 1207 va_start(va, V2); 1208 1209 llvm::SmallVector<llvm::Constant*, 16> Args; 1210 for (unsigned i = 0; i < NumElements; i++) { 1211 int n = va_arg(va, int); 1212 assert(n >= 0 && n < (int)NumElements * 2 && 1213 "Vector shuffle index out of bounds!"); 1214 Args.push_back(llvm::ConstantInt::get(llvm::Type::Int32Ty, n)); 1215 } 1216 1217 const char *Name = va_arg(va, const char *); 1218 va_end(va); 1219 1220 llvm::Constant *Mask = llvm::ConstantVector::get(&Args[0], NumElements); 1221 1222 return Builder.CreateShuffleVector(V1, V2, Mask, Name); 1223} 1224 1225llvm::Value *CodeGenFunction::EmitVector(llvm::Value * const *Vals, 1226 unsigned NumVals, bool isSplat) { 1227 llvm::Value *Vec 1228 = llvm::UndefValue::get(llvm::VectorType::get(Vals[0]->getType(), NumVals)); 1229 1230 for (unsigned i = 0, e = NumVals; i != e; ++i) { 1231 llvm::Value *Val = isSplat ? Vals[0] : Vals[i]; 1232 llvm::Value *Idx = llvm::ConstantInt::get(llvm::Type::Int32Ty, i); 1233 Vec = Builder.CreateInsertElement(Vec, Val, Idx, "tmp"); 1234 } 1235 1236 return Vec; 1237} 1238