CGExprScalar.cpp revision 2a41637a995affa1563f4d82a8b026e326a2faa0
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 "clang/Frontend/CodeGenOptions.h" 15#include "CodeGenFunction.h" 16#include "CGCXXABI.h" 17#include "CGObjCRuntime.h" 18#include "CodeGenModule.h" 19#include "CGDebugInfo.h" 20#include "clang/AST/ASTContext.h" 21#include "clang/AST/DeclObjC.h" 22#include "clang/AST/RecordLayout.h" 23#include "clang/AST/StmtVisitor.h" 24#include "clang/Basic/TargetInfo.h" 25#include "llvm/Constants.h" 26#include "llvm/Function.h" 27#include "llvm/GlobalVariable.h" 28#include "llvm/Intrinsics.h" 29#include "llvm/Module.h" 30#include "llvm/Support/CFG.h" 31#include "llvm/Target/TargetData.h" 32#include <cstdarg> 33 34using namespace clang; 35using namespace CodeGen; 36using llvm::Value; 37 38//===----------------------------------------------------------------------===// 39// Scalar Expression Emitter 40//===----------------------------------------------------------------------===// 41 42namespace { 43struct BinOpInfo { 44 Value *LHS; 45 Value *RHS; 46 QualType Ty; // Computation Type. 47 BinaryOperator::Opcode Opcode; // Opcode of BinOp to perform 48 const Expr *E; // Entire expr, for error unsupported. May not be binop. 49}; 50 51static bool MustVisitNullValue(const Expr *E) { 52 // If a null pointer expression's type is the C++0x nullptr_t, then 53 // it's not necessarily a simple constant and it must be evaluated 54 // for its potential side effects. 55 return E->getType()->isNullPtrType(); 56} 57 58class ScalarExprEmitter 59 : public StmtVisitor<ScalarExprEmitter, Value*> { 60 CodeGenFunction &CGF; 61 CGBuilderTy &Builder; 62 bool IgnoreResultAssign; 63 llvm::LLVMContext &VMContext; 64public: 65 66 ScalarExprEmitter(CodeGenFunction &cgf, bool ira=false) 67 : CGF(cgf), Builder(CGF.Builder), IgnoreResultAssign(ira), 68 VMContext(cgf.getLLVMContext()) { 69 } 70 71 //===--------------------------------------------------------------------===// 72 // Utilities 73 //===--------------------------------------------------------------------===// 74 75 bool TestAndClearIgnoreResultAssign() { 76 bool I = IgnoreResultAssign; 77 IgnoreResultAssign = false; 78 return I; 79 } 80 81 const llvm::Type *ConvertType(QualType T) { return CGF.ConvertType(T); } 82 LValue EmitLValue(const Expr *E) { return CGF.EmitLValue(E); } 83 LValue EmitCheckedLValue(const Expr *E) { return CGF.EmitCheckedLValue(E); } 84 85 Value *EmitLoadOfLValue(LValue LV, QualType T) { 86 return CGF.EmitLoadOfLValue(LV, T).getScalarVal(); 87 } 88 89 /// EmitLoadOfLValue - Given an expression with complex type that represents a 90 /// value l-value, this method emits the address of the l-value, then loads 91 /// and returns the result. 92 Value *EmitLoadOfLValue(const Expr *E) { 93 return EmitLoadOfLValue(EmitCheckedLValue(E), E->getType()); 94 } 95 96 /// EmitConversionToBool - Convert the specified expression value to a 97 /// boolean (i1) truth value. This is equivalent to "Val != 0". 98 Value *EmitConversionToBool(Value *Src, QualType DstTy); 99 100 /// EmitScalarConversion - Emit a conversion from the specified type to the 101 /// specified destination type, both of which are LLVM scalar types. 102 Value *EmitScalarConversion(Value *Src, QualType SrcTy, QualType DstTy); 103 104 /// EmitComplexToScalarConversion - Emit a conversion from the specified 105 /// complex type to the specified destination type, where the destination type 106 /// is an LLVM scalar type. 107 Value *EmitComplexToScalarConversion(CodeGenFunction::ComplexPairTy Src, 108 QualType SrcTy, QualType DstTy); 109 110 /// EmitNullValue - Emit a value that corresponds to null for the given type. 111 Value *EmitNullValue(QualType Ty); 112 113 /// EmitFloatToBoolConversion - Perform an FP to boolean conversion. 114 Value *EmitFloatToBoolConversion(Value *V) { 115 // Compare against 0.0 for fp scalars. 116 llvm::Value *Zero = llvm::Constant::getNullValue(V->getType()); 117 return Builder.CreateFCmpUNE(V, Zero, "tobool"); 118 } 119 120 /// EmitPointerToBoolConversion - Perform a pointer to boolean conversion. 121 Value *EmitPointerToBoolConversion(Value *V) { 122 Value *Zero = llvm::ConstantPointerNull::get( 123 cast<llvm::PointerType>(V->getType())); 124 return Builder.CreateICmpNE(V, Zero, "tobool"); 125 } 126 127 Value *EmitIntToBoolConversion(Value *V) { 128 // Because of the type rules of C, we often end up computing a 129 // logical value, then zero extending it to int, then wanting it 130 // as a logical value again. Optimize this common case. 131 if (llvm::ZExtInst *ZI = dyn_cast<llvm::ZExtInst>(V)) { 132 if (ZI->getOperand(0)->getType() == Builder.getInt1Ty()) { 133 Value *Result = ZI->getOperand(0); 134 // If there aren't any more uses, zap the instruction to save space. 135 // Note that there can be more uses, for example if this 136 // is the result of an assignment. 137 if (ZI->use_empty()) 138 ZI->eraseFromParent(); 139 return Result; 140 } 141 } 142 143 const llvm::IntegerType *Ty = cast<llvm::IntegerType>(V->getType()); 144 Value *Zero = llvm::ConstantInt::get(Ty, 0); 145 return Builder.CreateICmpNE(V, Zero, "tobool"); 146 } 147 148 //===--------------------------------------------------------------------===// 149 // Visitor Methods 150 //===--------------------------------------------------------------------===// 151 152 Value *Visit(Expr *E) { 153 llvm::DenseMap<const Expr *, llvm::Value *>::iterator I = 154 CGF.ConditionalSaveExprs.find(E); 155 if (I != CGF.ConditionalSaveExprs.end()) 156 return I->second; 157 158 return StmtVisitor<ScalarExprEmitter, Value*>::Visit(E); 159 } 160 161 Value *VisitStmt(Stmt *S) { 162 S->dump(CGF.getContext().getSourceManager()); 163 assert(0 && "Stmt can't have complex result type!"); 164 return 0; 165 } 166 Value *VisitExpr(Expr *S); 167 168 Value *VisitParenExpr(ParenExpr *PE) { 169 return Visit(PE->getSubExpr()); 170 } 171 172 // Leaves. 173 Value *VisitIntegerLiteral(const IntegerLiteral *E) { 174 return llvm::ConstantInt::get(VMContext, E->getValue()); 175 } 176 Value *VisitFloatingLiteral(const FloatingLiteral *E) { 177 return llvm::ConstantFP::get(VMContext, E->getValue()); 178 } 179 Value *VisitCharacterLiteral(const CharacterLiteral *E) { 180 return llvm::ConstantInt::get(ConvertType(E->getType()), E->getValue()); 181 } 182 Value *VisitCXXBoolLiteralExpr(const CXXBoolLiteralExpr *E) { 183 return llvm::ConstantInt::get(ConvertType(E->getType()), E->getValue()); 184 } 185 Value *VisitCXXScalarValueInitExpr(const CXXScalarValueInitExpr *E) { 186 return EmitNullValue(E->getType()); 187 } 188 Value *VisitGNUNullExpr(const GNUNullExpr *E) { 189 return EmitNullValue(E->getType()); 190 } 191 Value *VisitTypesCompatibleExpr(const TypesCompatibleExpr *E) { 192 return llvm::ConstantInt::get(ConvertType(E->getType()), 193 CGF.getContext().typesAreCompatible( 194 E->getArgType1(), E->getArgType2())); 195 } 196 Value *VisitOffsetOfExpr(OffsetOfExpr *E); 197 Value *VisitSizeOfAlignOfExpr(const SizeOfAlignOfExpr *E); 198 Value *VisitAddrLabelExpr(const AddrLabelExpr *E) { 199 llvm::Value *V = CGF.GetAddrOfLabel(E->getLabel()); 200 return Builder.CreateBitCast(V, ConvertType(E->getType())); 201 } 202 203 // l-values. 204 Value *VisitDeclRefExpr(DeclRefExpr *E) { 205 Expr::EvalResult Result; 206 if (!E->Evaluate(Result, CGF.getContext())) 207 return EmitLoadOfLValue(E); 208 209 assert(!Result.HasSideEffects && "Constant declref with side-effect?!"); 210 211 llvm::Constant *C; 212 if (Result.Val.isInt()) { 213 C = llvm::ConstantInt::get(VMContext, Result.Val.getInt()); 214 } else if (Result.Val.isFloat()) { 215 C = llvm::ConstantFP::get(VMContext, Result.Val.getFloat()); 216 } else { 217 return EmitLoadOfLValue(E); 218 } 219 220 // Make sure we emit a debug reference to the global variable. 221 if (VarDecl *VD = dyn_cast<VarDecl>(E->getDecl())) { 222 if (!CGF.getContext().DeclMustBeEmitted(VD)) 223 CGF.EmitDeclRefExprDbgValue(E, C); 224 } else if (isa<EnumConstantDecl>(E->getDecl())) { 225 CGF.EmitDeclRefExprDbgValue(E, C); 226 } 227 228 return C; 229 } 230 Value *VisitObjCSelectorExpr(ObjCSelectorExpr *E) { 231 return CGF.EmitObjCSelectorExpr(E); 232 } 233 Value *VisitObjCProtocolExpr(ObjCProtocolExpr *E) { 234 return CGF.EmitObjCProtocolExpr(E); 235 } 236 Value *VisitObjCIvarRefExpr(ObjCIvarRefExpr *E) { 237 return EmitLoadOfLValue(E); 238 } 239 Value *VisitObjCPropertyRefExpr(ObjCPropertyRefExpr *E) { 240 assert(E->getObjectKind() == OK_Ordinary && 241 "reached property reference without lvalue-to-rvalue"); 242 return EmitLoadOfLValue(E); 243 } 244 Value *VisitObjCMessageExpr(ObjCMessageExpr *E) { 245 return CGF.EmitObjCMessageExpr(E).getScalarVal(); 246 } 247 248 Value *VisitObjCIsaExpr(ObjCIsaExpr *E) { 249 LValue LV = CGF.EmitObjCIsaExpr(E); 250 Value *V = CGF.EmitLoadOfLValue(LV, E->getType()).getScalarVal(); 251 return V; 252 } 253 254 Value *VisitArraySubscriptExpr(ArraySubscriptExpr *E); 255 Value *VisitShuffleVectorExpr(ShuffleVectorExpr *E); 256 Value *VisitMemberExpr(MemberExpr *E); 257 Value *VisitExtVectorElementExpr(Expr *E) { return EmitLoadOfLValue(E); } 258 Value *VisitCompoundLiteralExpr(CompoundLiteralExpr *E) { 259 return EmitLoadOfLValue(E); 260 } 261 262 Value *VisitInitListExpr(InitListExpr *E); 263 264 Value *VisitImplicitValueInitExpr(const ImplicitValueInitExpr *E) { 265 return CGF.CGM.EmitNullConstant(E->getType()); 266 } 267 Value *VisitCastExpr(CastExpr *E) { 268 // Make sure to evaluate VLA bounds now so that we have them for later. 269 if (E->getType()->isVariablyModifiedType()) 270 CGF.EmitVLASize(E->getType()); 271 272 return EmitCastExpr(E); 273 } 274 Value *EmitCastExpr(CastExpr *E); 275 276 Value *VisitCallExpr(const CallExpr *E) { 277 if (E->getCallReturnType()->isReferenceType()) 278 return EmitLoadOfLValue(E); 279 280 return CGF.EmitCallExpr(E).getScalarVal(); 281 } 282 283 Value *VisitStmtExpr(const StmtExpr *E); 284 285 Value *VisitBlockDeclRefExpr(const BlockDeclRefExpr *E); 286 287 // Unary Operators. 288 Value *VisitUnaryPostDec(const UnaryOperator *E) { 289 LValue LV = EmitLValue(E->getSubExpr()); 290 return EmitScalarPrePostIncDec(E, LV, false, false); 291 } 292 Value *VisitUnaryPostInc(const UnaryOperator *E) { 293 LValue LV = EmitLValue(E->getSubExpr()); 294 return EmitScalarPrePostIncDec(E, LV, true, false); 295 } 296 Value *VisitUnaryPreDec(const UnaryOperator *E) { 297 LValue LV = EmitLValue(E->getSubExpr()); 298 return EmitScalarPrePostIncDec(E, LV, false, true); 299 } 300 Value *VisitUnaryPreInc(const UnaryOperator *E) { 301 LValue LV = EmitLValue(E->getSubExpr()); 302 return EmitScalarPrePostIncDec(E, LV, true, true); 303 } 304 305 llvm::Value *EmitScalarPrePostIncDec(const UnaryOperator *E, LValue LV, 306 bool isInc, bool isPre); 307 308 309 Value *VisitUnaryAddrOf(const UnaryOperator *E) { 310 // If the sub-expression is an instance member reference, 311 // EmitDeclRefLValue will magically emit it with the appropriate 312 // value as the "address". 313 return EmitLValue(E->getSubExpr()).getAddress(); 314 } 315 Value *VisitUnaryDeref(const UnaryOperator *E) { 316 if (E->getType()->isVoidType()) 317 return Visit(E->getSubExpr()); // the actual value should be unused 318 return EmitLoadOfLValue(E); 319 } 320 Value *VisitUnaryPlus(const UnaryOperator *E) { 321 // This differs from gcc, though, most likely due to a bug in gcc. 322 TestAndClearIgnoreResultAssign(); 323 return Visit(E->getSubExpr()); 324 } 325 Value *VisitUnaryMinus (const UnaryOperator *E); 326 Value *VisitUnaryNot (const UnaryOperator *E); 327 Value *VisitUnaryLNot (const UnaryOperator *E); 328 Value *VisitUnaryReal (const UnaryOperator *E); 329 Value *VisitUnaryImag (const UnaryOperator *E); 330 Value *VisitUnaryExtension(const UnaryOperator *E) { 331 return Visit(E->getSubExpr()); 332 } 333 334 // C++ 335 Value *VisitCXXDefaultArgExpr(CXXDefaultArgExpr *DAE) { 336 return Visit(DAE->getExpr()); 337 } 338 Value *VisitCXXThisExpr(CXXThisExpr *TE) { 339 return CGF.LoadCXXThis(); 340 } 341 342 Value *VisitCXXExprWithTemporaries(CXXExprWithTemporaries *E) { 343 return CGF.EmitCXXExprWithTemporaries(E).getScalarVal(); 344 } 345 Value *VisitCXXNewExpr(const CXXNewExpr *E) { 346 return CGF.EmitCXXNewExpr(E); 347 } 348 Value *VisitCXXDeleteExpr(const CXXDeleteExpr *E) { 349 CGF.EmitCXXDeleteExpr(E); 350 return 0; 351 } 352 Value *VisitUnaryTypeTraitExpr(const UnaryTypeTraitExpr *E) { 353 return llvm::ConstantInt::get(Builder.getInt1Ty(), E->getValue()); 354 } 355 356 Value *VisitCXXPseudoDestructorExpr(const CXXPseudoDestructorExpr *E) { 357 // C++ [expr.pseudo]p1: 358 // The result shall only be used as the operand for the function call 359 // operator (), and the result of such a call has type void. The only 360 // effect is the evaluation of the postfix-expression before the dot or 361 // arrow. 362 CGF.EmitScalarExpr(E->getBase()); 363 return 0; 364 } 365 366 Value *VisitCXXNullPtrLiteralExpr(const CXXNullPtrLiteralExpr *E) { 367 return EmitNullValue(E->getType()); 368 } 369 370 Value *VisitCXXThrowExpr(const CXXThrowExpr *E) { 371 CGF.EmitCXXThrowExpr(E); 372 return 0; 373 } 374 375 Value *VisitCXXNoexceptExpr(const CXXNoexceptExpr *E) { 376 return llvm::ConstantInt::get(Builder.getInt1Ty(), E->getValue()); 377 } 378 379 // Binary Operators. 380 Value *EmitMul(const BinOpInfo &Ops) { 381 if (Ops.Ty->hasSignedIntegerRepresentation()) { 382 switch (CGF.getContext().getLangOptions().getSignedOverflowBehavior()) { 383 case LangOptions::SOB_Undefined: 384 return Builder.CreateNSWMul(Ops.LHS, Ops.RHS, "mul"); 385 case LangOptions::SOB_Defined: 386 return Builder.CreateMul(Ops.LHS, Ops.RHS, "mul"); 387 case LangOptions::SOB_Trapping: 388 return EmitOverflowCheckedBinOp(Ops); 389 } 390 } 391 392 if (Ops.LHS->getType()->isFPOrFPVectorTy()) 393 return Builder.CreateFMul(Ops.LHS, Ops.RHS, "mul"); 394 return Builder.CreateMul(Ops.LHS, Ops.RHS, "mul"); 395 } 396 bool isTrapvOverflowBehavior() { 397 return CGF.getContext().getLangOptions().getSignedOverflowBehavior() 398 == LangOptions::SOB_Trapping; 399 } 400 /// Create a binary op that checks for overflow. 401 /// Currently only supports +, - and *. 402 Value *EmitOverflowCheckedBinOp(const BinOpInfo &Ops); 403 // Emit the overflow BB when -ftrapv option is activated. 404 void EmitOverflowBB(llvm::BasicBlock *overflowBB) { 405 Builder.SetInsertPoint(overflowBB); 406 llvm::Function *Trap = CGF.CGM.getIntrinsic(llvm::Intrinsic::trap); 407 Builder.CreateCall(Trap); 408 Builder.CreateUnreachable(); 409 } 410 // Check for undefined division and modulus behaviors. 411 void EmitUndefinedBehaviorIntegerDivAndRemCheck(const BinOpInfo &Ops, 412 llvm::Value *Zero,bool isDiv); 413 Value *EmitDiv(const BinOpInfo &Ops); 414 Value *EmitRem(const BinOpInfo &Ops); 415 Value *EmitAdd(const BinOpInfo &Ops); 416 Value *EmitSub(const BinOpInfo &Ops); 417 Value *EmitShl(const BinOpInfo &Ops); 418 Value *EmitShr(const BinOpInfo &Ops); 419 Value *EmitAnd(const BinOpInfo &Ops) { 420 return Builder.CreateAnd(Ops.LHS, Ops.RHS, "and"); 421 } 422 Value *EmitXor(const BinOpInfo &Ops) { 423 return Builder.CreateXor(Ops.LHS, Ops.RHS, "xor"); 424 } 425 Value *EmitOr (const BinOpInfo &Ops) { 426 return Builder.CreateOr(Ops.LHS, Ops.RHS, "or"); 427 } 428 429 BinOpInfo EmitBinOps(const BinaryOperator *E); 430 LValue EmitCompoundAssignLValue(const CompoundAssignOperator *E, 431 Value *(ScalarExprEmitter::*F)(const BinOpInfo &), 432 Value *&Result); 433 434 Value *EmitCompoundAssign(const CompoundAssignOperator *E, 435 Value *(ScalarExprEmitter::*F)(const BinOpInfo &)); 436 437 // Binary operators and binary compound assignment operators. 438#define HANDLEBINOP(OP) \ 439 Value *VisitBin ## OP(const BinaryOperator *E) { \ 440 return Emit ## OP(EmitBinOps(E)); \ 441 } \ 442 Value *VisitBin ## OP ## Assign(const CompoundAssignOperator *E) { \ 443 return EmitCompoundAssign(E, &ScalarExprEmitter::Emit ## OP); \ 444 } 445 HANDLEBINOP(Mul) 446 HANDLEBINOP(Div) 447 HANDLEBINOP(Rem) 448 HANDLEBINOP(Add) 449 HANDLEBINOP(Sub) 450 HANDLEBINOP(Shl) 451 HANDLEBINOP(Shr) 452 HANDLEBINOP(And) 453 HANDLEBINOP(Xor) 454 HANDLEBINOP(Or) 455#undef HANDLEBINOP 456 457 // Comparisons. 458 Value *EmitCompare(const BinaryOperator *E, unsigned UICmpOpc, 459 unsigned SICmpOpc, unsigned FCmpOpc); 460#define VISITCOMP(CODE, UI, SI, FP) \ 461 Value *VisitBin##CODE(const BinaryOperator *E) { \ 462 return EmitCompare(E, llvm::ICmpInst::UI, llvm::ICmpInst::SI, \ 463 llvm::FCmpInst::FP); } 464 VISITCOMP(LT, ICMP_ULT, ICMP_SLT, FCMP_OLT) 465 VISITCOMP(GT, ICMP_UGT, ICMP_SGT, FCMP_OGT) 466 VISITCOMP(LE, ICMP_ULE, ICMP_SLE, FCMP_OLE) 467 VISITCOMP(GE, ICMP_UGE, ICMP_SGE, FCMP_OGE) 468 VISITCOMP(EQ, ICMP_EQ , ICMP_EQ , FCMP_OEQ) 469 VISITCOMP(NE, ICMP_NE , ICMP_NE , FCMP_UNE) 470#undef VISITCOMP 471 472 Value *VisitBinAssign (const BinaryOperator *E); 473 474 Value *VisitBinLAnd (const BinaryOperator *E); 475 Value *VisitBinLOr (const BinaryOperator *E); 476 Value *VisitBinComma (const BinaryOperator *E); 477 478 Value *VisitBinPtrMemD(const Expr *E) { return EmitLoadOfLValue(E); } 479 Value *VisitBinPtrMemI(const Expr *E) { return EmitLoadOfLValue(E); } 480 481 // Other Operators. 482 Value *VisitBlockExpr(const BlockExpr *BE); 483 Value *VisitConditionalOperator(const ConditionalOperator *CO); 484 Value *VisitChooseExpr(ChooseExpr *CE); 485 Value *VisitVAArgExpr(VAArgExpr *VE); 486 Value *VisitObjCStringLiteral(const ObjCStringLiteral *E) { 487 return CGF.EmitObjCStringLiteral(E); 488 } 489}; 490} // end anonymous namespace. 491 492//===----------------------------------------------------------------------===// 493// Utilities 494//===----------------------------------------------------------------------===// 495 496/// EmitConversionToBool - Convert the specified expression value to a 497/// boolean (i1) truth value. This is equivalent to "Val != 0". 498Value *ScalarExprEmitter::EmitConversionToBool(Value *Src, QualType SrcType) { 499 assert(SrcType.isCanonical() && "EmitScalarConversion strips typedefs"); 500 501 if (SrcType->isRealFloatingType()) 502 return EmitFloatToBoolConversion(Src); 503 504 if (const MemberPointerType *MPT = dyn_cast<MemberPointerType>(SrcType)) 505 return CGF.CGM.getCXXABI().EmitMemberPointerIsNotNull(CGF, Src, MPT); 506 507 assert((SrcType->isIntegerType() || isa<llvm::PointerType>(Src->getType())) && 508 "Unknown scalar type to convert"); 509 510 if (isa<llvm::IntegerType>(Src->getType())) 511 return EmitIntToBoolConversion(Src); 512 513 assert(isa<llvm::PointerType>(Src->getType())); 514 return EmitPointerToBoolConversion(Src); 515} 516 517/// EmitScalarConversion - Emit a conversion from the specified type to the 518/// specified destination type, both of which are LLVM scalar types. 519Value *ScalarExprEmitter::EmitScalarConversion(Value *Src, QualType SrcType, 520 QualType DstType) { 521 SrcType = CGF.getContext().getCanonicalType(SrcType); 522 DstType = CGF.getContext().getCanonicalType(DstType); 523 if (SrcType == DstType) return Src; 524 525 if (DstType->isVoidType()) return 0; 526 527 // Handle conversions to bool first, they are special: comparisons against 0. 528 if (DstType->isBooleanType()) 529 return EmitConversionToBool(Src, SrcType); 530 531 const llvm::Type *DstTy = ConvertType(DstType); 532 533 // Ignore conversions like int -> uint. 534 if (Src->getType() == DstTy) 535 return Src; 536 537 // Handle pointer conversions next: pointers can only be converted to/from 538 // other pointers and integers. Check for pointer types in terms of LLVM, as 539 // some native types (like Obj-C id) may map to a pointer type. 540 if (isa<llvm::PointerType>(DstTy)) { 541 // The source value may be an integer, or a pointer. 542 if (isa<llvm::PointerType>(Src->getType())) 543 return Builder.CreateBitCast(Src, DstTy, "conv"); 544 545 assert(SrcType->isIntegerType() && "Not ptr->ptr or int->ptr conversion?"); 546 // First, convert to the correct width so that we control the kind of 547 // extension. 548 const llvm::Type *MiddleTy = CGF.IntPtrTy; 549 bool InputSigned = SrcType->isSignedIntegerType(); 550 llvm::Value* IntResult = 551 Builder.CreateIntCast(Src, MiddleTy, InputSigned, "conv"); 552 // Then, cast to pointer. 553 return Builder.CreateIntToPtr(IntResult, DstTy, "conv"); 554 } 555 556 if (isa<llvm::PointerType>(Src->getType())) { 557 // Must be an ptr to int cast. 558 assert(isa<llvm::IntegerType>(DstTy) && "not ptr->int?"); 559 return Builder.CreatePtrToInt(Src, DstTy, "conv"); 560 } 561 562 // A scalar can be splatted to an extended vector of the same element type 563 if (DstType->isExtVectorType() && !SrcType->isVectorType()) { 564 // Cast the scalar to element type 565 QualType EltTy = DstType->getAs<ExtVectorType>()->getElementType(); 566 llvm::Value *Elt = EmitScalarConversion(Src, SrcType, EltTy); 567 568 // Insert the element in element zero of an undef vector 569 llvm::Value *UnV = llvm::UndefValue::get(DstTy); 570 llvm::Value *Idx = llvm::ConstantInt::get(CGF.Int32Ty, 0); 571 UnV = Builder.CreateInsertElement(UnV, Elt, Idx, "tmp"); 572 573 // Splat the element across to all elements 574 llvm::SmallVector<llvm::Constant*, 16> Args; 575 unsigned NumElements = cast<llvm::VectorType>(DstTy)->getNumElements(); 576 for (unsigned i = 0; i < NumElements; i++) 577 Args.push_back(llvm::ConstantInt::get(CGF.Int32Ty, 0)); 578 579 llvm::Constant *Mask = llvm::ConstantVector::get(&Args[0], NumElements); 580 llvm::Value *Yay = Builder.CreateShuffleVector(UnV, UnV, Mask, "splat"); 581 return Yay; 582 } 583 584 // Allow bitcast from vector to integer/fp of the same size. 585 if (isa<llvm::VectorType>(Src->getType()) || 586 isa<llvm::VectorType>(DstTy)) 587 return Builder.CreateBitCast(Src, DstTy, "conv"); 588 589 // Finally, we have the arithmetic types: real int/float. 590 if (isa<llvm::IntegerType>(Src->getType())) { 591 bool InputSigned = SrcType->isSignedIntegerType(); 592 if (isa<llvm::IntegerType>(DstTy)) 593 return Builder.CreateIntCast(Src, DstTy, InputSigned, "conv"); 594 else if (InputSigned) 595 return Builder.CreateSIToFP(Src, DstTy, "conv"); 596 else 597 return Builder.CreateUIToFP(Src, DstTy, "conv"); 598 } 599 600 assert(Src->getType()->isFloatingPointTy() && "Unknown real conversion"); 601 if (isa<llvm::IntegerType>(DstTy)) { 602 if (DstType->isSignedIntegerType()) 603 return Builder.CreateFPToSI(Src, DstTy, "conv"); 604 else 605 return Builder.CreateFPToUI(Src, DstTy, "conv"); 606 } 607 608 assert(DstTy->isFloatingPointTy() && "Unknown real conversion"); 609 if (DstTy->getTypeID() < Src->getType()->getTypeID()) 610 return Builder.CreateFPTrunc(Src, DstTy, "conv"); 611 else 612 return Builder.CreateFPExt(Src, DstTy, "conv"); 613} 614 615/// EmitComplexToScalarConversion - Emit a conversion from the specified complex 616/// type to the specified destination type, where the destination type is an 617/// LLVM scalar type. 618Value *ScalarExprEmitter:: 619EmitComplexToScalarConversion(CodeGenFunction::ComplexPairTy Src, 620 QualType SrcTy, QualType DstTy) { 621 // Get the source element type. 622 SrcTy = SrcTy->getAs<ComplexType>()->getElementType(); 623 624 // Handle conversions to bool first, they are special: comparisons against 0. 625 if (DstTy->isBooleanType()) { 626 // Complex != 0 -> (Real != 0) | (Imag != 0) 627 Src.first = EmitScalarConversion(Src.first, SrcTy, DstTy); 628 Src.second = EmitScalarConversion(Src.second, SrcTy, DstTy); 629 return Builder.CreateOr(Src.first, Src.second, "tobool"); 630 } 631 632 // C99 6.3.1.7p2: "When a value of complex type is converted to a real type, 633 // the imaginary part of the complex value is discarded and the value of the 634 // real part is converted according to the conversion rules for the 635 // corresponding real type. 636 return EmitScalarConversion(Src.first, SrcTy, DstTy); 637} 638 639Value *ScalarExprEmitter::EmitNullValue(QualType Ty) { 640 if (const MemberPointerType *MPT = Ty->getAs<MemberPointerType>()) 641 return CGF.CGM.getCXXABI().EmitNullMemberPointer(MPT); 642 643 return llvm::Constant::getNullValue(ConvertType(Ty)); 644} 645 646//===----------------------------------------------------------------------===// 647// Visitor Methods 648//===----------------------------------------------------------------------===// 649 650Value *ScalarExprEmitter::VisitExpr(Expr *E) { 651 CGF.ErrorUnsupported(E, "scalar expression"); 652 if (E->getType()->isVoidType()) 653 return 0; 654 return llvm::UndefValue::get(CGF.ConvertType(E->getType())); 655} 656 657Value *ScalarExprEmitter::VisitShuffleVectorExpr(ShuffleVectorExpr *E) { 658 // Vector Mask Case 659 if (E->getNumSubExprs() == 2 || 660 (E->getNumSubExprs() == 3 && E->getExpr(2)->getType()->isVectorType())) { 661 Value *LHS = CGF.EmitScalarExpr(E->getExpr(0)); 662 Value *RHS = CGF.EmitScalarExpr(E->getExpr(1)); 663 Value *Mask; 664 665 const llvm::VectorType *LTy = cast<llvm::VectorType>(LHS->getType()); 666 unsigned LHSElts = LTy->getNumElements(); 667 668 if (E->getNumSubExprs() == 3) { 669 Mask = CGF.EmitScalarExpr(E->getExpr(2)); 670 671 // Shuffle LHS & RHS into one input vector. 672 llvm::SmallVector<llvm::Constant*, 32> concat; 673 for (unsigned i = 0; i != LHSElts; ++i) { 674 concat.push_back(llvm::ConstantInt::get(CGF.Int32Ty, 2*i)); 675 concat.push_back(llvm::ConstantInt::get(CGF.Int32Ty, 2*i+1)); 676 } 677 678 Value* CV = llvm::ConstantVector::get(concat.begin(), concat.size()); 679 LHS = Builder.CreateShuffleVector(LHS, RHS, CV, "concat"); 680 LHSElts *= 2; 681 } else { 682 Mask = RHS; 683 } 684 685 const llvm::VectorType *MTy = cast<llvm::VectorType>(Mask->getType()); 686 llvm::Constant* EltMask; 687 688 // Treat vec3 like vec4. 689 if ((LHSElts == 6) && (E->getNumSubExprs() == 3)) 690 EltMask = llvm::ConstantInt::get(MTy->getElementType(), 691 (1 << llvm::Log2_32(LHSElts+2))-1); 692 else if ((LHSElts == 3) && (E->getNumSubExprs() == 2)) 693 EltMask = llvm::ConstantInt::get(MTy->getElementType(), 694 (1 << llvm::Log2_32(LHSElts+1))-1); 695 else 696 EltMask = llvm::ConstantInt::get(MTy->getElementType(), 697 (1 << llvm::Log2_32(LHSElts))-1); 698 699 // Mask off the high bits of each shuffle index. 700 llvm::SmallVector<llvm::Constant *, 32> MaskV; 701 for (unsigned i = 0, e = MTy->getNumElements(); i != e; ++i) 702 MaskV.push_back(EltMask); 703 704 Value* MaskBits = llvm::ConstantVector::get(MaskV.begin(), MaskV.size()); 705 Mask = Builder.CreateAnd(Mask, MaskBits, "mask"); 706 707 // newv = undef 708 // mask = mask & maskbits 709 // for each elt 710 // n = extract mask i 711 // x = extract val n 712 // newv = insert newv, x, i 713 const llvm::VectorType *RTy = llvm::VectorType::get(LTy->getElementType(), 714 MTy->getNumElements()); 715 Value* NewV = llvm::UndefValue::get(RTy); 716 for (unsigned i = 0, e = MTy->getNumElements(); i != e; ++i) { 717 Value *Indx = llvm::ConstantInt::get(CGF.Int32Ty, i); 718 Indx = Builder.CreateExtractElement(Mask, Indx, "shuf_idx"); 719 Indx = Builder.CreateZExt(Indx, CGF.Int32Ty, "idx_zext"); 720 721 // Handle vec3 special since the index will be off by one for the RHS. 722 if ((LHSElts == 6) && (E->getNumSubExprs() == 3)) { 723 Value *cmpIndx, *newIndx; 724 cmpIndx = Builder.CreateICmpUGT(Indx, 725 llvm::ConstantInt::get(CGF.Int32Ty, 3), 726 "cmp_shuf_idx"); 727 newIndx = Builder.CreateSub(Indx, llvm::ConstantInt::get(CGF.Int32Ty,1), 728 "shuf_idx_adj"); 729 Indx = Builder.CreateSelect(cmpIndx, newIndx, Indx, "sel_shuf_idx"); 730 } 731 Value *VExt = Builder.CreateExtractElement(LHS, Indx, "shuf_elt"); 732 NewV = Builder.CreateInsertElement(NewV, VExt, Indx, "shuf_ins"); 733 } 734 return NewV; 735 } 736 737 Value* V1 = CGF.EmitScalarExpr(E->getExpr(0)); 738 Value* V2 = CGF.EmitScalarExpr(E->getExpr(1)); 739 740 // Handle vec3 special since the index will be off by one for the RHS. 741 llvm::SmallVector<llvm::Constant*, 32> indices; 742 for (unsigned i = 2; i < E->getNumSubExprs(); i++) { 743 llvm::Constant *C = cast<llvm::Constant>(CGF.EmitScalarExpr(E->getExpr(i))); 744 const llvm::VectorType *VTy = cast<llvm::VectorType>(V1->getType()); 745 if (VTy->getNumElements() == 3) { 746 if (llvm::ConstantInt *CI = dyn_cast<llvm::ConstantInt>(C)) { 747 uint64_t cVal = CI->getZExtValue(); 748 if (cVal > 3) { 749 C = llvm::ConstantInt::get(C->getType(), cVal-1); 750 } 751 } 752 } 753 indices.push_back(C); 754 } 755 756 Value* SV = llvm::ConstantVector::get(indices.begin(), indices.size()); 757 return Builder.CreateShuffleVector(V1, V2, SV, "shuffle"); 758} 759Value *ScalarExprEmitter::VisitMemberExpr(MemberExpr *E) { 760 Expr::EvalResult Result; 761 if (E->Evaluate(Result, CGF.getContext()) && Result.Val.isInt()) { 762 if (E->isArrow()) 763 CGF.EmitScalarExpr(E->getBase()); 764 else 765 EmitLValue(E->getBase()); 766 return llvm::ConstantInt::get(VMContext, Result.Val.getInt()); 767 } 768 769 // Emit debug info for aggregate now, if it was delayed to reduce 770 // debug info size. 771 CGDebugInfo *DI = CGF.getDebugInfo(); 772 if (DI && CGF.CGM.getCodeGenOpts().LimitDebugInfo) { 773 QualType PQTy = E->getBase()->IgnoreParenImpCasts()->getType(); 774 if (const PointerType * PTy = dyn_cast<PointerType>(PQTy)) 775 if (FieldDecl *M = dyn_cast<FieldDecl>(E->getMemberDecl())) 776 DI->getOrCreateRecordType(PTy->getPointeeType(), 777 M->getParent()->getLocation()); 778 } 779 return EmitLoadOfLValue(E); 780} 781 782Value *ScalarExprEmitter::VisitArraySubscriptExpr(ArraySubscriptExpr *E) { 783 TestAndClearIgnoreResultAssign(); 784 785 // Emit subscript expressions in rvalue context's. For most cases, this just 786 // loads the lvalue formed by the subscript expr. However, we have to be 787 // careful, because the base of a vector subscript is occasionally an rvalue, 788 // so we can't get it as an lvalue. 789 if (!E->getBase()->getType()->isVectorType()) 790 return EmitLoadOfLValue(E); 791 792 // Handle the vector case. The base must be a vector, the index must be an 793 // integer value. 794 Value *Base = Visit(E->getBase()); 795 Value *Idx = Visit(E->getIdx()); 796 bool IdxSigned = E->getIdx()->getType()->isSignedIntegerType(); 797 Idx = Builder.CreateIntCast(Idx, CGF.Int32Ty, IdxSigned, "vecidxcast"); 798 return Builder.CreateExtractElement(Base, Idx, "vecext"); 799} 800 801static llvm::Constant *getMaskElt(llvm::ShuffleVectorInst *SVI, unsigned Idx, 802 unsigned Off, const llvm::Type *I32Ty) { 803 int MV = SVI->getMaskValue(Idx); 804 if (MV == -1) 805 return llvm::UndefValue::get(I32Ty); 806 return llvm::ConstantInt::get(I32Ty, Off+MV); 807} 808 809Value *ScalarExprEmitter::VisitInitListExpr(InitListExpr *E) { 810 bool Ignore = TestAndClearIgnoreResultAssign(); 811 (void)Ignore; 812 assert (Ignore == false && "init list ignored"); 813 unsigned NumInitElements = E->getNumInits(); 814 815 if (E->hadArrayRangeDesignator()) 816 CGF.ErrorUnsupported(E, "GNU array range designator extension"); 817 818 const llvm::VectorType *VType = 819 dyn_cast<llvm::VectorType>(ConvertType(E->getType())); 820 821 // We have a scalar in braces. Just use the first element. 822 if (!VType) 823 return Visit(E->getInit(0)); 824 825 unsigned ResElts = VType->getNumElements(); 826 827 // Loop over initializers collecting the Value for each, and remembering 828 // whether the source was swizzle (ExtVectorElementExpr). This will allow 829 // us to fold the shuffle for the swizzle into the shuffle for the vector 830 // initializer, since LLVM optimizers generally do not want to touch 831 // shuffles. 832 unsigned CurIdx = 0; 833 bool VIsUndefShuffle = false; 834 llvm::Value *V = llvm::UndefValue::get(VType); 835 for (unsigned i = 0; i != NumInitElements; ++i) { 836 Expr *IE = E->getInit(i); 837 Value *Init = Visit(IE); 838 llvm::SmallVector<llvm::Constant*, 16> Args; 839 840 const llvm::VectorType *VVT = dyn_cast<llvm::VectorType>(Init->getType()); 841 842 // Handle scalar elements. If the scalar initializer is actually one 843 // element of a different vector of the same width, use shuffle instead of 844 // extract+insert. 845 if (!VVT) { 846 if (isa<ExtVectorElementExpr>(IE)) { 847 llvm::ExtractElementInst *EI = cast<llvm::ExtractElementInst>(Init); 848 849 if (EI->getVectorOperandType()->getNumElements() == ResElts) { 850 llvm::ConstantInt *C = cast<llvm::ConstantInt>(EI->getIndexOperand()); 851 Value *LHS = 0, *RHS = 0; 852 if (CurIdx == 0) { 853 // insert into undef -> shuffle (src, undef) 854 Args.push_back(C); 855 for (unsigned j = 1; j != ResElts; ++j) 856 Args.push_back(llvm::UndefValue::get(CGF.Int32Ty)); 857 858 LHS = EI->getVectorOperand(); 859 RHS = V; 860 VIsUndefShuffle = true; 861 } else if (VIsUndefShuffle) { 862 // insert into undefshuffle && size match -> shuffle (v, src) 863 llvm::ShuffleVectorInst *SVV = cast<llvm::ShuffleVectorInst>(V); 864 for (unsigned j = 0; j != CurIdx; ++j) 865 Args.push_back(getMaskElt(SVV, j, 0, CGF.Int32Ty)); 866 Args.push_back(llvm::ConstantInt::get(CGF.Int32Ty, 867 ResElts + C->getZExtValue())); 868 for (unsigned j = CurIdx + 1; j != ResElts; ++j) 869 Args.push_back(llvm::UndefValue::get(CGF.Int32Ty)); 870 871 LHS = cast<llvm::ShuffleVectorInst>(V)->getOperand(0); 872 RHS = EI->getVectorOperand(); 873 VIsUndefShuffle = false; 874 } 875 if (!Args.empty()) { 876 llvm::Constant *Mask = llvm::ConstantVector::get(&Args[0], ResElts); 877 V = Builder.CreateShuffleVector(LHS, RHS, Mask); 878 ++CurIdx; 879 continue; 880 } 881 } 882 } 883 Value *Idx = llvm::ConstantInt::get(CGF.Int32Ty, CurIdx); 884 V = Builder.CreateInsertElement(V, Init, Idx, "vecinit"); 885 VIsUndefShuffle = false; 886 ++CurIdx; 887 continue; 888 } 889 890 unsigned InitElts = VVT->getNumElements(); 891 892 // If the initializer is an ExtVecEltExpr (a swizzle), and the swizzle's 893 // input is the same width as the vector being constructed, generate an 894 // optimized shuffle of the swizzle input into the result. 895 unsigned Offset = (CurIdx == 0) ? 0 : ResElts; 896 if (isa<ExtVectorElementExpr>(IE)) { 897 llvm::ShuffleVectorInst *SVI = cast<llvm::ShuffleVectorInst>(Init); 898 Value *SVOp = SVI->getOperand(0); 899 const llvm::VectorType *OpTy = cast<llvm::VectorType>(SVOp->getType()); 900 901 if (OpTy->getNumElements() == ResElts) { 902 for (unsigned j = 0; j != CurIdx; ++j) { 903 // If the current vector initializer is a shuffle with undef, merge 904 // this shuffle directly into it. 905 if (VIsUndefShuffle) { 906 Args.push_back(getMaskElt(cast<llvm::ShuffleVectorInst>(V), j, 0, 907 CGF.Int32Ty)); 908 } else { 909 Args.push_back(llvm::ConstantInt::get(CGF.Int32Ty, j)); 910 } 911 } 912 for (unsigned j = 0, je = InitElts; j != je; ++j) 913 Args.push_back(getMaskElt(SVI, j, Offset, CGF.Int32Ty)); 914 for (unsigned j = CurIdx + InitElts; j != ResElts; ++j) 915 Args.push_back(llvm::UndefValue::get(CGF.Int32Ty)); 916 917 if (VIsUndefShuffle) 918 V = cast<llvm::ShuffleVectorInst>(V)->getOperand(0); 919 920 Init = SVOp; 921 } 922 } 923 924 // Extend init to result vector length, and then shuffle its contribution 925 // to the vector initializer into V. 926 if (Args.empty()) { 927 for (unsigned j = 0; j != InitElts; ++j) 928 Args.push_back(llvm::ConstantInt::get(CGF.Int32Ty, j)); 929 for (unsigned j = InitElts; j != ResElts; ++j) 930 Args.push_back(llvm::UndefValue::get(CGF.Int32Ty)); 931 llvm::Constant *Mask = llvm::ConstantVector::get(&Args[0], ResElts); 932 Init = Builder.CreateShuffleVector(Init, llvm::UndefValue::get(VVT), 933 Mask, "vext"); 934 935 Args.clear(); 936 for (unsigned j = 0; j != CurIdx; ++j) 937 Args.push_back(llvm::ConstantInt::get(CGF.Int32Ty, j)); 938 for (unsigned j = 0; j != InitElts; ++j) 939 Args.push_back(llvm::ConstantInt::get(CGF.Int32Ty, j+Offset)); 940 for (unsigned j = CurIdx + InitElts; j != ResElts; ++j) 941 Args.push_back(llvm::UndefValue::get(CGF.Int32Ty)); 942 } 943 944 // If V is undef, make sure it ends up on the RHS of the shuffle to aid 945 // merging subsequent shuffles into this one. 946 if (CurIdx == 0) 947 std::swap(V, Init); 948 llvm::Constant *Mask = llvm::ConstantVector::get(&Args[0], ResElts); 949 V = Builder.CreateShuffleVector(V, Init, Mask, "vecinit"); 950 VIsUndefShuffle = isa<llvm::UndefValue>(Init); 951 CurIdx += InitElts; 952 } 953 954 // FIXME: evaluate codegen vs. shuffling against constant null vector. 955 // Emit remaining default initializers. 956 const llvm::Type *EltTy = VType->getElementType(); 957 958 // Emit remaining default initializers 959 for (/* Do not initialize i*/; CurIdx < ResElts; ++CurIdx) { 960 Value *Idx = llvm::ConstantInt::get(CGF.Int32Ty, CurIdx); 961 llvm::Value *Init = llvm::Constant::getNullValue(EltTy); 962 V = Builder.CreateInsertElement(V, Init, Idx, "vecinit"); 963 } 964 return V; 965} 966 967static bool ShouldNullCheckClassCastValue(const CastExpr *CE) { 968 const Expr *E = CE->getSubExpr(); 969 970 if (CE->getCastKind() == CK_UncheckedDerivedToBase) 971 return false; 972 973 if (isa<CXXThisExpr>(E)) { 974 // We always assume that 'this' is never null. 975 return false; 976 } 977 978 if (const ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(CE)) { 979 // And that glvalue casts are never null. 980 if (ICE->getValueKind() != VK_RValue) 981 return false; 982 } 983 984 return true; 985} 986 987// VisitCastExpr - Emit code for an explicit or implicit cast. Implicit casts 988// have to handle a more broad range of conversions than explicit casts, as they 989// handle things like function to ptr-to-function decay etc. 990Value *ScalarExprEmitter::EmitCastExpr(CastExpr *CE) { 991 Expr *E = CE->getSubExpr(); 992 QualType DestTy = CE->getType(); 993 CastKind Kind = CE->getCastKind(); 994 995 if (!DestTy->isVoidType()) 996 TestAndClearIgnoreResultAssign(); 997 998 // Since almost all cast kinds apply to scalars, this switch doesn't have 999 // a default case, so the compiler will warn on a missing case. The cases 1000 // are in the same order as in the CastKind enum. 1001 switch (Kind) { 1002 case CK_Dependent: llvm_unreachable("dependent cast kind in IR gen!"); 1003 1004 case CK_LValueBitCast: 1005 case CK_ObjCObjectLValueCast: { 1006 Value *V = EmitLValue(E).getAddress(); 1007 V = Builder.CreateBitCast(V, 1008 ConvertType(CGF.getContext().getPointerType(DestTy))); 1009 return EmitLoadOfLValue(CGF.MakeAddrLValue(V, DestTy), DestTy); 1010 } 1011 1012 case CK_AnyPointerToObjCPointerCast: 1013 case CK_AnyPointerToBlockPointerCast: 1014 case CK_BitCast: { 1015 Value *Src = Visit(const_cast<Expr*>(E)); 1016 return Builder.CreateBitCast(Src, ConvertType(DestTy)); 1017 } 1018 case CK_NoOp: 1019 case CK_UserDefinedConversion: 1020 return Visit(const_cast<Expr*>(E)); 1021 1022 case CK_BaseToDerived: { 1023 const CXXRecordDecl *DerivedClassDecl = 1024 DestTy->getCXXRecordDeclForPointerType(); 1025 1026 return CGF.GetAddressOfDerivedClass(Visit(E), DerivedClassDecl, 1027 CE->path_begin(), CE->path_end(), 1028 ShouldNullCheckClassCastValue(CE)); 1029 } 1030 case CK_UncheckedDerivedToBase: 1031 case CK_DerivedToBase: { 1032 const RecordType *DerivedClassTy = 1033 E->getType()->getAs<PointerType>()->getPointeeType()->getAs<RecordType>(); 1034 CXXRecordDecl *DerivedClassDecl = 1035 cast<CXXRecordDecl>(DerivedClassTy->getDecl()); 1036 1037 return CGF.GetAddressOfBaseClass(Visit(E), DerivedClassDecl, 1038 CE->path_begin(), CE->path_end(), 1039 ShouldNullCheckClassCastValue(CE)); 1040 } 1041 case CK_Dynamic: { 1042 Value *V = Visit(const_cast<Expr*>(E)); 1043 const CXXDynamicCastExpr *DCE = cast<CXXDynamicCastExpr>(CE); 1044 return CGF.EmitDynamicCast(V, DCE); 1045 } 1046 1047 case CK_ArrayToPointerDecay: { 1048 assert(E->getType()->isArrayType() && 1049 "Array to pointer decay must have array source type!"); 1050 1051 Value *V = EmitLValue(E).getAddress(); // Bitfields can't be arrays. 1052 1053 // Note that VLA pointers are always decayed, so we don't need to do 1054 // anything here. 1055 if (!E->getType()->isVariableArrayType()) { 1056 assert(isa<llvm::PointerType>(V->getType()) && "Expected pointer"); 1057 assert(isa<llvm::ArrayType>(cast<llvm::PointerType>(V->getType()) 1058 ->getElementType()) && 1059 "Expected pointer to array"); 1060 V = Builder.CreateStructGEP(V, 0, "arraydecay"); 1061 } 1062 1063 return V; 1064 } 1065 case CK_FunctionToPointerDecay: 1066 return EmitLValue(E).getAddress(); 1067 1068 case CK_NullToPointer: 1069 if (MustVisitNullValue(E)) 1070 (void) Visit(E); 1071 1072 return llvm::ConstantPointerNull::get( 1073 cast<llvm::PointerType>(ConvertType(DestTy))); 1074 1075 case CK_NullToMemberPointer: { 1076 if (MustVisitNullValue(E)) 1077 (void) Visit(E); 1078 1079 const MemberPointerType *MPT = CE->getType()->getAs<MemberPointerType>(); 1080 return CGF.CGM.getCXXABI().EmitNullMemberPointer(MPT); 1081 } 1082 1083 case CK_BaseToDerivedMemberPointer: 1084 case CK_DerivedToBaseMemberPointer: { 1085 Value *Src = Visit(E); 1086 1087 // Note that the AST doesn't distinguish between checked and 1088 // unchecked member pointer conversions, so we always have to 1089 // implement checked conversions here. This is inefficient when 1090 // actual control flow may be required in order to perform the 1091 // check, which it is for data member pointers (but not member 1092 // function pointers on Itanium and ARM). 1093 return CGF.CGM.getCXXABI().EmitMemberPointerConversion(CGF, CE, Src); 1094 } 1095 1096 case CK_FloatingRealToComplex: 1097 case CK_FloatingComplexCast: 1098 case CK_IntegralRealToComplex: 1099 case CK_IntegralComplexCast: 1100 case CK_IntegralComplexToFloatingComplex: 1101 case CK_FloatingComplexToIntegralComplex: 1102 case CK_ConstructorConversion: 1103 case CK_ToUnion: 1104 llvm_unreachable("scalar cast to non-scalar value"); 1105 break; 1106 1107 case CK_GetObjCProperty: { 1108 assert(CGF.getContext().hasSameUnqualifiedType(E->getType(), DestTy)); 1109 assert(E->isLValue() && E->getObjectKind() == OK_ObjCProperty && 1110 "CK_GetObjCProperty for non-lvalue or non-ObjCProperty"); 1111 RValue RV = CGF.EmitLoadOfLValue(CGF.EmitLValue(E), E->getType()); 1112 return RV.getScalarVal(); 1113 } 1114 1115 case CK_LValueToRValue: 1116 assert(CGF.getContext().hasSameUnqualifiedType(E->getType(), DestTy)); 1117 assert(E->isGLValue() && "lvalue-to-rvalue applied to r-value!"); 1118 return Visit(const_cast<Expr*>(E)); 1119 1120 case CK_IntegralToPointer: { 1121 Value *Src = Visit(const_cast<Expr*>(E)); 1122 1123 // First, convert to the correct width so that we control the kind of 1124 // extension. 1125 const llvm::Type *MiddleTy = CGF.IntPtrTy; 1126 bool InputSigned = E->getType()->isSignedIntegerType(); 1127 llvm::Value* IntResult = 1128 Builder.CreateIntCast(Src, MiddleTy, InputSigned, "conv"); 1129 1130 return Builder.CreateIntToPtr(IntResult, ConvertType(DestTy)); 1131 } 1132 case CK_PointerToIntegral: { 1133 Value *Src = Visit(const_cast<Expr*>(E)); 1134 1135 // Handle conversion to bool correctly. 1136 if (DestTy->isBooleanType()) 1137 return EmitScalarConversion(Src, E->getType(), DestTy); 1138 1139 return Builder.CreatePtrToInt(Src, ConvertType(DestTy)); 1140 } 1141 case CK_ToVoid: { 1142 CGF.EmitIgnoredExpr(E); 1143 return 0; 1144 } 1145 case CK_VectorSplat: { 1146 const llvm::Type *DstTy = ConvertType(DestTy); 1147 Value *Elt = Visit(const_cast<Expr*>(E)); 1148 1149 // Insert the element in element zero of an undef vector 1150 llvm::Value *UnV = llvm::UndefValue::get(DstTy); 1151 llvm::Value *Idx = llvm::ConstantInt::get(CGF.Int32Ty, 0); 1152 UnV = Builder.CreateInsertElement(UnV, Elt, Idx, "tmp"); 1153 1154 // Splat the element across to all elements 1155 llvm::SmallVector<llvm::Constant*, 16> Args; 1156 unsigned NumElements = cast<llvm::VectorType>(DstTy)->getNumElements(); 1157 llvm::Constant *Zero = llvm::ConstantInt::get(CGF.Int32Ty, 0); 1158 for (unsigned i = 0; i < NumElements; i++) 1159 Args.push_back(Zero); 1160 1161 llvm::Constant *Mask = llvm::ConstantVector::get(&Args[0], NumElements); 1162 llvm::Value *Yay = Builder.CreateShuffleVector(UnV, UnV, Mask, "splat"); 1163 return Yay; 1164 } 1165 1166 case CK_IntegralCast: 1167 case CK_IntegralToFloating: 1168 case CK_FloatingToIntegral: 1169 case CK_FloatingCast: 1170 return EmitScalarConversion(Visit(E), E->getType(), DestTy); 1171 1172 case CK_IntegralToBoolean: 1173 return EmitIntToBoolConversion(Visit(E)); 1174 case CK_PointerToBoolean: 1175 return EmitPointerToBoolConversion(Visit(E)); 1176 case CK_FloatingToBoolean: 1177 return EmitFloatToBoolConversion(Visit(E)); 1178 case CK_MemberPointerToBoolean: { 1179 llvm::Value *MemPtr = Visit(E); 1180 const MemberPointerType *MPT = E->getType()->getAs<MemberPointerType>(); 1181 return CGF.CGM.getCXXABI().EmitMemberPointerIsNotNull(CGF, MemPtr, MPT); 1182 } 1183 1184 case CK_FloatingComplexToReal: 1185 case CK_IntegralComplexToReal: 1186 return CGF.EmitComplexExpr(E, false, true).first; 1187 1188 case CK_FloatingComplexToBoolean: 1189 case CK_IntegralComplexToBoolean: { 1190 CodeGenFunction::ComplexPairTy V = CGF.EmitComplexExpr(E); 1191 1192 // TODO: kill this function off, inline appropriate case here 1193 return EmitComplexToScalarConversion(V, E->getType(), DestTy); 1194 } 1195 1196 } 1197 1198 llvm_unreachable("unknown scalar cast"); 1199 return 0; 1200} 1201 1202Value *ScalarExprEmitter::VisitStmtExpr(const StmtExpr *E) { 1203 return CGF.EmitCompoundStmt(*E->getSubStmt(), 1204 !E->getType()->isVoidType()).getScalarVal(); 1205} 1206 1207Value *ScalarExprEmitter::VisitBlockDeclRefExpr(const BlockDeclRefExpr *E) { 1208 llvm::Value *V = CGF.GetAddrOfBlockDecl(E); 1209 if (E->getType().isObjCGCWeak()) 1210 return CGF.CGM.getObjCRuntime().EmitObjCWeakRead(CGF, V); 1211 return CGF.EmitLoadOfScalar(V, false, 0, E->getType()); 1212} 1213 1214//===----------------------------------------------------------------------===// 1215// Unary Operators 1216//===----------------------------------------------------------------------===// 1217 1218llvm::Value *ScalarExprEmitter:: 1219EmitScalarPrePostIncDec(const UnaryOperator *E, LValue LV, 1220 bool isInc, bool isPre) { 1221 1222 QualType ValTy = E->getSubExpr()->getType(); 1223 llvm::Value *InVal = EmitLoadOfLValue(LV, ValTy); 1224 1225 int AmountVal = isInc ? 1 : -1; 1226 1227 if (ValTy->isPointerType() && 1228 ValTy->getAs<PointerType>()->isVariableArrayType()) { 1229 // The amount of the addition/subtraction needs to account for the VLA size 1230 CGF.ErrorUnsupported(E, "VLA pointer inc/dec"); 1231 } 1232 1233 llvm::Value *NextVal; 1234 if (const llvm::PointerType *PT = 1235 dyn_cast<llvm::PointerType>(InVal->getType())) { 1236 llvm::Constant *Inc = llvm::ConstantInt::get(CGF.Int32Ty, AmountVal); 1237 if (!isa<llvm::FunctionType>(PT->getElementType())) { 1238 QualType PTEE = ValTy->getPointeeType(); 1239 if (const ObjCObjectType *OIT = PTEE->getAs<ObjCObjectType>()) { 1240 // Handle interface types, which are not represented with a concrete 1241 // type. 1242 int size = CGF.getContext().getTypeSize(OIT) / 8; 1243 if (!isInc) 1244 size = -size; 1245 Inc = llvm::ConstantInt::get(Inc->getType(), size); 1246 const llvm::Type *i8Ty = llvm::Type::getInt8PtrTy(VMContext); 1247 InVal = Builder.CreateBitCast(InVal, i8Ty); 1248 NextVal = Builder.CreateGEP(InVal, Inc, "add.ptr"); 1249 llvm::Value *lhs = LV.getAddress(); 1250 lhs = Builder.CreateBitCast(lhs, llvm::PointerType::getUnqual(i8Ty)); 1251 LV = CGF.MakeAddrLValue(lhs, ValTy); 1252 } else 1253 NextVal = Builder.CreateInBoundsGEP(InVal, Inc, "ptrincdec"); 1254 } else { 1255 const llvm::Type *i8Ty = llvm::Type::getInt8PtrTy(VMContext); 1256 NextVal = Builder.CreateBitCast(InVal, i8Ty, "tmp"); 1257 NextVal = Builder.CreateGEP(NextVal, Inc, "ptrincdec"); 1258 NextVal = Builder.CreateBitCast(NextVal, InVal->getType()); 1259 } 1260 } else if (InVal->getType()->isIntegerTy(1) && isInc) { 1261 // Bool++ is an interesting case, due to promotion rules, we get: 1262 // Bool++ -> Bool = Bool+1 -> Bool = (int)Bool+1 -> 1263 // Bool = ((int)Bool+1) != 0 1264 // An interesting aspect of this is that increment is always true. 1265 // Decrement does not have this property. 1266 NextVal = llvm::ConstantInt::getTrue(VMContext); 1267 } else if (isa<llvm::IntegerType>(InVal->getType())) { 1268 NextVal = llvm::ConstantInt::get(InVal->getType(), AmountVal); 1269 1270 if (!ValTy->isSignedIntegerType()) 1271 // Unsigned integer inc is always two's complement. 1272 NextVal = Builder.CreateAdd(InVal, NextVal, isInc ? "inc" : "dec"); 1273 else { 1274 switch (CGF.getContext().getLangOptions().getSignedOverflowBehavior()) { 1275 case LangOptions::SOB_Undefined: 1276 NextVal = Builder.CreateNSWAdd(InVal, NextVal, isInc ? "inc" : "dec"); 1277 break; 1278 case LangOptions::SOB_Defined: 1279 NextVal = Builder.CreateAdd(InVal, NextVal, isInc ? "inc" : "dec"); 1280 break; 1281 case LangOptions::SOB_Trapping: 1282 BinOpInfo BinOp; 1283 BinOp.LHS = InVal; 1284 BinOp.RHS = NextVal; 1285 BinOp.Ty = E->getType(); 1286 BinOp.Opcode = BO_Add; 1287 BinOp.E = E; 1288 NextVal = EmitOverflowCheckedBinOp(BinOp); 1289 break; 1290 } 1291 } 1292 } else { 1293 // Add the inc/dec to the real part. 1294 if (InVal->getType()->isFloatTy()) 1295 NextVal = 1296 llvm::ConstantFP::get(VMContext, 1297 llvm::APFloat(static_cast<float>(AmountVal))); 1298 else if (InVal->getType()->isDoubleTy()) 1299 NextVal = 1300 llvm::ConstantFP::get(VMContext, 1301 llvm::APFloat(static_cast<double>(AmountVal))); 1302 else { 1303 llvm::APFloat F(static_cast<float>(AmountVal)); 1304 bool ignored; 1305 F.convert(CGF.Target.getLongDoubleFormat(), llvm::APFloat::rmTowardZero, 1306 &ignored); 1307 NextVal = llvm::ConstantFP::get(VMContext, F); 1308 } 1309 NextVal = Builder.CreateFAdd(InVal, NextVal, isInc ? "inc" : "dec"); 1310 } 1311 1312 // Store the updated result through the lvalue. 1313 if (LV.isBitField()) 1314 CGF.EmitStoreThroughBitfieldLValue(RValue::get(NextVal), LV, ValTy, &NextVal); 1315 else 1316 CGF.EmitStoreThroughLValue(RValue::get(NextVal), LV, ValTy); 1317 1318 // If this is a postinc, return the value read from memory, otherwise use the 1319 // updated value. 1320 return isPre ? NextVal : InVal; 1321} 1322 1323 1324 1325Value *ScalarExprEmitter::VisitUnaryMinus(const UnaryOperator *E) { 1326 TestAndClearIgnoreResultAssign(); 1327 // Emit unary minus with EmitSub so we handle overflow cases etc. 1328 BinOpInfo BinOp; 1329 BinOp.RHS = Visit(E->getSubExpr()); 1330 1331 if (BinOp.RHS->getType()->isFPOrFPVectorTy()) 1332 BinOp.LHS = llvm::ConstantFP::getZeroValueForNegation(BinOp.RHS->getType()); 1333 else 1334 BinOp.LHS = llvm::Constant::getNullValue(BinOp.RHS->getType()); 1335 BinOp.Ty = E->getType(); 1336 BinOp.Opcode = BO_Sub; 1337 BinOp.E = E; 1338 return EmitSub(BinOp); 1339} 1340 1341Value *ScalarExprEmitter::VisitUnaryNot(const UnaryOperator *E) { 1342 TestAndClearIgnoreResultAssign(); 1343 Value *Op = Visit(E->getSubExpr()); 1344 return Builder.CreateNot(Op, "neg"); 1345} 1346 1347Value *ScalarExprEmitter::VisitUnaryLNot(const UnaryOperator *E) { 1348 // Compare operand to zero. 1349 Value *BoolVal = CGF.EvaluateExprAsBool(E->getSubExpr()); 1350 1351 // Invert value. 1352 // TODO: Could dynamically modify easy computations here. For example, if 1353 // the operand is an icmp ne, turn into icmp eq. 1354 BoolVal = Builder.CreateNot(BoolVal, "lnot"); 1355 1356 // ZExt result to the expr type. 1357 return Builder.CreateZExt(BoolVal, ConvertType(E->getType()), "lnot.ext"); 1358} 1359 1360Value *ScalarExprEmitter::VisitOffsetOfExpr(OffsetOfExpr *E) { 1361 // Try folding the offsetof to a constant. 1362 Expr::EvalResult EvalResult; 1363 if (E->Evaluate(EvalResult, CGF.getContext())) 1364 return llvm::ConstantInt::get(VMContext, EvalResult.Val.getInt()); 1365 1366 // Loop over the components of the offsetof to compute the value. 1367 unsigned n = E->getNumComponents(); 1368 const llvm::Type* ResultType = ConvertType(E->getType()); 1369 llvm::Value* Result = llvm::Constant::getNullValue(ResultType); 1370 QualType CurrentType = E->getTypeSourceInfo()->getType(); 1371 for (unsigned i = 0; i != n; ++i) { 1372 OffsetOfExpr::OffsetOfNode ON = E->getComponent(i); 1373 llvm::Value *Offset = 0; 1374 switch (ON.getKind()) { 1375 case OffsetOfExpr::OffsetOfNode::Array: { 1376 // Compute the index 1377 Expr *IdxExpr = E->getIndexExpr(ON.getArrayExprIndex()); 1378 llvm::Value* Idx = CGF.EmitScalarExpr(IdxExpr); 1379 bool IdxSigned = IdxExpr->getType()->isSignedIntegerType(); 1380 Idx = Builder.CreateIntCast(Idx, ResultType, IdxSigned, "conv"); 1381 1382 // Save the element type 1383 CurrentType = 1384 CGF.getContext().getAsArrayType(CurrentType)->getElementType(); 1385 1386 // Compute the element size 1387 llvm::Value* ElemSize = llvm::ConstantInt::get(ResultType, 1388 CGF.getContext().getTypeSizeInChars(CurrentType).getQuantity()); 1389 1390 // Multiply out to compute the result 1391 Offset = Builder.CreateMul(Idx, ElemSize); 1392 break; 1393 } 1394 1395 case OffsetOfExpr::OffsetOfNode::Field: { 1396 FieldDecl *MemberDecl = ON.getField(); 1397 RecordDecl *RD = CurrentType->getAs<RecordType>()->getDecl(); 1398 const ASTRecordLayout &RL = CGF.getContext().getASTRecordLayout(RD); 1399 1400 // Compute the index of the field in its parent. 1401 unsigned i = 0; 1402 // FIXME: It would be nice if we didn't have to loop here! 1403 for (RecordDecl::field_iterator Field = RD->field_begin(), 1404 FieldEnd = RD->field_end(); 1405 Field != FieldEnd; (void)++Field, ++i) { 1406 if (*Field == MemberDecl) 1407 break; 1408 } 1409 assert(i < RL.getFieldCount() && "offsetof field in wrong type"); 1410 1411 // Compute the offset to the field 1412 int64_t OffsetInt = RL.getFieldOffset(i) / 1413 CGF.getContext().getCharWidth(); 1414 Offset = llvm::ConstantInt::get(ResultType, OffsetInt); 1415 1416 // Save the element type. 1417 CurrentType = MemberDecl->getType(); 1418 break; 1419 } 1420 1421 case OffsetOfExpr::OffsetOfNode::Identifier: 1422 llvm_unreachable("dependent __builtin_offsetof"); 1423 1424 case OffsetOfExpr::OffsetOfNode::Base: { 1425 if (ON.getBase()->isVirtual()) { 1426 CGF.ErrorUnsupported(E, "virtual base in offsetof"); 1427 continue; 1428 } 1429 1430 RecordDecl *RD = CurrentType->getAs<RecordType>()->getDecl(); 1431 const ASTRecordLayout &RL = CGF.getContext().getASTRecordLayout(RD); 1432 1433 // Save the element type. 1434 CurrentType = ON.getBase()->getType(); 1435 1436 // Compute the offset to the base. 1437 const RecordType *BaseRT = CurrentType->getAs<RecordType>(); 1438 CXXRecordDecl *BaseRD = cast<CXXRecordDecl>(BaseRT->getDecl()); 1439 int64_t OffsetInt = RL.getBaseClassOffsetInBits(BaseRD) / 1440 CGF.getContext().getCharWidth(); 1441 Offset = llvm::ConstantInt::get(ResultType, OffsetInt); 1442 break; 1443 } 1444 } 1445 Result = Builder.CreateAdd(Result, Offset); 1446 } 1447 return Result; 1448} 1449 1450/// VisitSizeOfAlignOfExpr - Return the size or alignment of the type of 1451/// argument of the sizeof expression as an integer. 1452Value * 1453ScalarExprEmitter::VisitSizeOfAlignOfExpr(const SizeOfAlignOfExpr *E) { 1454 QualType TypeToSize = E->getTypeOfArgument(); 1455 if (E->isSizeOf()) { 1456 if (const VariableArrayType *VAT = 1457 CGF.getContext().getAsVariableArrayType(TypeToSize)) { 1458 if (E->isArgumentType()) { 1459 // sizeof(type) - make sure to emit the VLA size. 1460 CGF.EmitVLASize(TypeToSize); 1461 } else { 1462 // C99 6.5.3.4p2: If the argument is an expression of type 1463 // VLA, it is evaluated. 1464 CGF.EmitIgnoredExpr(E->getArgumentExpr()); 1465 } 1466 1467 return CGF.GetVLASize(VAT); 1468 } 1469 } 1470 1471 // If this isn't sizeof(vla), the result must be constant; use the constant 1472 // folding logic so we don't have to duplicate it here. 1473 Expr::EvalResult Result; 1474 E->Evaluate(Result, CGF.getContext()); 1475 return llvm::ConstantInt::get(VMContext, Result.Val.getInt()); 1476} 1477 1478Value *ScalarExprEmitter::VisitUnaryReal(const UnaryOperator *E) { 1479 Expr *Op = E->getSubExpr(); 1480 if (Op->getType()->isAnyComplexType()) { 1481 // If it's an l-value, load through the appropriate subobject l-value. 1482 // Note that we have to ask E because Op might be an l-value that 1483 // this won't work for, e.g. an Obj-C property. 1484 if (E->isGLValue()) 1485 return CGF.EmitLoadOfLValue(CGF.EmitLValue(E), E->getType()) 1486 .getScalarVal(); 1487 1488 // Otherwise, calculate and project. 1489 return CGF.EmitComplexExpr(Op, false, true).first; 1490 } 1491 1492 return Visit(Op); 1493} 1494 1495Value *ScalarExprEmitter::VisitUnaryImag(const UnaryOperator *E) { 1496 Expr *Op = E->getSubExpr(); 1497 if (Op->getType()->isAnyComplexType()) { 1498 // If it's an l-value, load through the appropriate subobject l-value. 1499 // Note that we have to ask E because Op might be an l-value that 1500 // this won't work for, e.g. an Obj-C property. 1501 if (Op->isGLValue()) 1502 return CGF.EmitLoadOfLValue(CGF.EmitLValue(E), E->getType()) 1503 .getScalarVal(); 1504 1505 // Otherwise, calculate and project. 1506 return CGF.EmitComplexExpr(Op, true, false).second; 1507 } 1508 1509 // __imag on a scalar returns zero. Emit the subexpr to ensure side 1510 // effects are evaluated, but not the actual value. 1511 CGF.EmitScalarExpr(Op, true); 1512 return llvm::Constant::getNullValue(ConvertType(E->getType())); 1513} 1514 1515//===----------------------------------------------------------------------===// 1516// Binary Operators 1517//===----------------------------------------------------------------------===// 1518 1519BinOpInfo ScalarExprEmitter::EmitBinOps(const BinaryOperator *E) { 1520 TestAndClearIgnoreResultAssign(); 1521 BinOpInfo Result; 1522 Result.LHS = Visit(E->getLHS()); 1523 Result.RHS = Visit(E->getRHS()); 1524 Result.Ty = E->getType(); 1525 Result.Opcode = E->getOpcode(); 1526 Result.E = E; 1527 return Result; 1528} 1529 1530LValue ScalarExprEmitter::EmitCompoundAssignLValue( 1531 const CompoundAssignOperator *E, 1532 Value *(ScalarExprEmitter::*Func)(const BinOpInfo &), 1533 Value *&Result) { 1534 QualType LHSTy = E->getLHS()->getType(); 1535 BinOpInfo OpInfo; 1536 1537 if (E->getComputationResultType()->isAnyComplexType()) { 1538 // This needs to go through the complex expression emitter, but it's a tad 1539 // complicated to do that... I'm leaving it out for now. (Note that we do 1540 // actually need the imaginary part of the RHS for multiplication and 1541 // division.) 1542 CGF.ErrorUnsupported(E, "complex compound assignment"); 1543 Result = llvm::UndefValue::get(CGF.ConvertType(E->getType())); 1544 return LValue(); 1545 } 1546 1547 // Emit the RHS first. __block variables need to have the rhs evaluated 1548 // first, plus this should improve codegen a little. 1549 OpInfo.RHS = Visit(E->getRHS()); 1550 OpInfo.Ty = E->getComputationResultType(); 1551 OpInfo.Opcode = E->getOpcode(); 1552 OpInfo.E = E; 1553 // Load/convert the LHS. 1554 LValue LHSLV = EmitCheckedLValue(E->getLHS()); 1555 OpInfo.LHS = EmitLoadOfLValue(LHSLV, LHSTy); 1556 OpInfo.LHS = EmitScalarConversion(OpInfo.LHS, LHSTy, 1557 E->getComputationLHSType()); 1558 1559 // Expand the binary operator. 1560 Result = (this->*Func)(OpInfo); 1561 1562 // Convert the result back to the LHS type. 1563 Result = EmitScalarConversion(Result, E->getComputationResultType(), LHSTy); 1564 1565 // Store the result value into the LHS lvalue. Bit-fields are handled 1566 // specially because the result is altered by the store, i.e., [C99 6.5.16p1] 1567 // 'An assignment expression has the value of the left operand after the 1568 // assignment...'. 1569 if (LHSLV.isBitField()) 1570 CGF.EmitStoreThroughBitfieldLValue(RValue::get(Result), LHSLV, LHSTy, 1571 &Result); 1572 else 1573 CGF.EmitStoreThroughLValue(RValue::get(Result), LHSLV, LHSTy); 1574 1575 return LHSLV; 1576} 1577 1578Value *ScalarExprEmitter::EmitCompoundAssign(const CompoundAssignOperator *E, 1579 Value *(ScalarExprEmitter::*Func)(const BinOpInfo &)) { 1580 bool Ignore = TestAndClearIgnoreResultAssign(); 1581 Value *RHS; 1582 LValue LHS = EmitCompoundAssignLValue(E, Func, RHS); 1583 1584 // If the result is clearly ignored, return now. 1585 if (Ignore) 1586 return 0; 1587 1588 // The result of an assignment in C is the assigned r-value. 1589 if (!CGF.getContext().getLangOptions().CPlusPlus) 1590 return RHS; 1591 1592 // Objective-C property assignment never reloads the value following a store. 1593 if (LHS.isPropertyRef()) 1594 return RHS; 1595 1596 // If the lvalue is non-volatile, return the computed value of the assignment. 1597 if (!LHS.isVolatileQualified()) 1598 return RHS; 1599 1600 // Otherwise, reload the value. 1601 return EmitLoadOfLValue(LHS, E->getType()); 1602} 1603 1604void ScalarExprEmitter::EmitUndefinedBehaviorIntegerDivAndRemCheck( 1605 const BinOpInfo &Ops, 1606 llvm::Value *Zero, bool isDiv) { 1607 llvm::BasicBlock *overflowBB = CGF.createBasicBlock("overflow", CGF.CurFn); 1608 llvm::BasicBlock *contBB = 1609 CGF.createBasicBlock(isDiv ? "div.cont" : "rem.cont", CGF.CurFn); 1610 1611 const llvm::IntegerType *Ty = cast<llvm::IntegerType>(Zero->getType()); 1612 1613 if (Ops.Ty->hasSignedIntegerRepresentation()) { 1614 llvm::Value *IntMin = 1615 llvm::ConstantInt::get(VMContext, 1616 llvm::APInt::getSignedMinValue(Ty->getBitWidth())); 1617 llvm::Value *NegOne = llvm::ConstantInt::get(Ty, -1ULL); 1618 1619 llvm::Value *Cond1 = Builder.CreateICmpEQ(Ops.RHS, Zero); 1620 llvm::Value *LHSCmp = Builder.CreateICmpEQ(Ops.LHS, IntMin); 1621 llvm::Value *RHSCmp = Builder.CreateICmpEQ(Ops.RHS, NegOne); 1622 llvm::Value *Cond2 = Builder.CreateAnd(LHSCmp, RHSCmp, "and"); 1623 Builder.CreateCondBr(Builder.CreateOr(Cond1, Cond2, "or"), 1624 overflowBB, contBB); 1625 } else { 1626 CGF.Builder.CreateCondBr(Builder.CreateICmpEQ(Ops.RHS, Zero), 1627 overflowBB, contBB); 1628 } 1629 EmitOverflowBB(overflowBB); 1630 Builder.SetInsertPoint(contBB); 1631} 1632 1633Value *ScalarExprEmitter::EmitDiv(const BinOpInfo &Ops) { 1634 if (isTrapvOverflowBehavior()) { 1635 llvm::Value *Zero = llvm::Constant::getNullValue(ConvertType(Ops.Ty)); 1636 1637 if (Ops.Ty->isIntegerType()) 1638 EmitUndefinedBehaviorIntegerDivAndRemCheck(Ops, Zero, true); 1639 else if (Ops.Ty->isRealFloatingType()) { 1640 llvm::BasicBlock *overflowBB = CGF.createBasicBlock("overflow", 1641 CGF.CurFn); 1642 llvm::BasicBlock *DivCont = CGF.createBasicBlock("div.cont", CGF.CurFn); 1643 CGF.Builder.CreateCondBr(Builder.CreateFCmpOEQ(Ops.RHS, Zero), 1644 overflowBB, DivCont); 1645 EmitOverflowBB(overflowBB); 1646 Builder.SetInsertPoint(DivCont); 1647 } 1648 } 1649 if (Ops.LHS->getType()->isFPOrFPVectorTy()) 1650 return Builder.CreateFDiv(Ops.LHS, Ops.RHS, "div"); 1651 else if (Ops.Ty->hasUnsignedIntegerRepresentation()) 1652 return Builder.CreateUDiv(Ops.LHS, Ops.RHS, "div"); 1653 else 1654 return Builder.CreateSDiv(Ops.LHS, Ops.RHS, "div"); 1655} 1656 1657Value *ScalarExprEmitter::EmitRem(const BinOpInfo &Ops) { 1658 // Rem in C can't be a floating point type: C99 6.5.5p2. 1659 if (isTrapvOverflowBehavior()) { 1660 llvm::Value *Zero = llvm::Constant::getNullValue(ConvertType(Ops.Ty)); 1661 1662 if (Ops.Ty->isIntegerType()) 1663 EmitUndefinedBehaviorIntegerDivAndRemCheck(Ops, Zero, false); 1664 } 1665 1666 if (Ops.Ty->isUnsignedIntegerType()) 1667 return Builder.CreateURem(Ops.LHS, Ops.RHS, "rem"); 1668 else 1669 return Builder.CreateSRem(Ops.LHS, Ops.RHS, "rem"); 1670} 1671 1672Value *ScalarExprEmitter::EmitOverflowCheckedBinOp(const BinOpInfo &Ops) { 1673 unsigned IID; 1674 unsigned OpID = 0; 1675 1676 switch (Ops.Opcode) { 1677 case BO_Add: 1678 case BO_AddAssign: 1679 OpID = 1; 1680 IID = llvm::Intrinsic::sadd_with_overflow; 1681 break; 1682 case BO_Sub: 1683 case BO_SubAssign: 1684 OpID = 2; 1685 IID = llvm::Intrinsic::ssub_with_overflow; 1686 break; 1687 case BO_Mul: 1688 case BO_MulAssign: 1689 OpID = 3; 1690 IID = llvm::Intrinsic::smul_with_overflow; 1691 break; 1692 default: 1693 assert(false && "Unsupported operation for overflow detection"); 1694 IID = 0; 1695 } 1696 OpID <<= 1; 1697 OpID |= 1; 1698 1699 const llvm::Type *opTy = CGF.CGM.getTypes().ConvertType(Ops.Ty); 1700 1701 llvm::Function *intrinsic = CGF.CGM.getIntrinsic(IID, &opTy, 1); 1702 1703 Value *resultAndOverflow = Builder.CreateCall2(intrinsic, Ops.LHS, Ops.RHS); 1704 Value *result = Builder.CreateExtractValue(resultAndOverflow, 0); 1705 Value *overflow = Builder.CreateExtractValue(resultAndOverflow, 1); 1706 1707 // Branch in case of overflow. 1708 llvm::BasicBlock *initialBB = Builder.GetInsertBlock(); 1709 llvm::BasicBlock *overflowBB = CGF.createBasicBlock("overflow", CGF.CurFn); 1710 llvm::BasicBlock *continueBB = CGF.createBasicBlock("nooverflow", CGF.CurFn); 1711 1712 Builder.CreateCondBr(overflow, overflowBB, continueBB); 1713 1714 // Handle overflow with llvm.trap. 1715 const std::string *handlerName = 1716 &CGF.getContext().getLangOptions().OverflowHandler; 1717 if (handlerName->empty()) { 1718 EmitOverflowBB(overflowBB); 1719 Builder.SetInsertPoint(continueBB); 1720 return result; 1721 } 1722 1723 // If an overflow handler is set, then we want to call it and then use its 1724 // result, if it returns. 1725 Builder.SetInsertPoint(overflowBB); 1726 1727 // Get the overflow handler. 1728 const llvm::Type *Int8Ty = llvm::Type::getInt8Ty(VMContext); 1729 std::vector<const llvm::Type*> argTypes; 1730 argTypes.push_back(CGF.Int64Ty); argTypes.push_back(CGF.Int64Ty); 1731 argTypes.push_back(Int8Ty); argTypes.push_back(Int8Ty); 1732 llvm::FunctionType *handlerTy = 1733 llvm::FunctionType::get(CGF.Int64Ty, argTypes, true); 1734 llvm::Value *handler = CGF.CGM.CreateRuntimeFunction(handlerTy, *handlerName); 1735 1736 // Sign extend the args to 64-bit, so that we can use the same handler for 1737 // all types of overflow. 1738 llvm::Value *lhs = Builder.CreateSExt(Ops.LHS, CGF.Int64Ty); 1739 llvm::Value *rhs = Builder.CreateSExt(Ops.RHS, CGF.Int64Ty); 1740 1741 // Call the handler with the two arguments, the operation, and the size of 1742 // the result. 1743 llvm::Value *handlerResult = Builder.CreateCall4(handler, lhs, rhs, 1744 Builder.getInt8(OpID), 1745 Builder.getInt8(cast<llvm::IntegerType>(opTy)->getBitWidth())); 1746 1747 // Truncate the result back to the desired size. 1748 handlerResult = Builder.CreateTrunc(handlerResult, opTy); 1749 Builder.CreateBr(continueBB); 1750 1751 Builder.SetInsertPoint(continueBB); 1752 llvm::PHINode *phi = Builder.CreatePHI(opTy); 1753 phi->reserveOperandSpace(2); 1754 phi->addIncoming(result, initialBB); 1755 phi->addIncoming(handlerResult, overflowBB); 1756 1757 return phi; 1758} 1759 1760Value *ScalarExprEmitter::EmitAdd(const BinOpInfo &Ops) { 1761 if (!Ops.Ty->isAnyPointerType()) { 1762 if (Ops.Ty->hasSignedIntegerRepresentation()) { 1763 switch (CGF.getContext().getLangOptions().getSignedOverflowBehavior()) { 1764 case LangOptions::SOB_Undefined: 1765 return Builder.CreateNSWAdd(Ops.LHS, Ops.RHS, "add"); 1766 case LangOptions::SOB_Defined: 1767 return Builder.CreateAdd(Ops.LHS, Ops.RHS, "add"); 1768 case LangOptions::SOB_Trapping: 1769 return EmitOverflowCheckedBinOp(Ops); 1770 } 1771 } 1772 1773 if (Ops.LHS->getType()->isFPOrFPVectorTy()) 1774 return Builder.CreateFAdd(Ops.LHS, Ops.RHS, "add"); 1775 1776 return Builder.CreateAdd(Ops.LHS, Ops.RHS, "add"); 1777 } 1778 1779 // Must have binary (not unary) expr here. Unary pointer decrement doesn't 1780 // use this path. 1781 const BinaryOperator *BinOp = cast<BinaryOperator>(Ops.E); 1782 1783 if (Ops.Ty->isPointerType() && 1784 Ops.Ty->getAs<PointerType>()->isVariableArrayType()) { 1785 // The amount of the addition needs to account for the VLA size 1786 CGF.ErrorUnsupported(BinOp, "VLA pointer addition"); 1787 } 1788 1789 Value *Ptr, *Idx; 1790 Expr *IdxExp; 1791 const PointerType *PT = BinOp->getLHS()->getType()->getAs<PointerType>(); 1792 const ObjCObjectPointerType *OPT = 1793 BinOp->getLHS()->getType()->getAs<ObjCObjectPointerType>(); 1794 if (PT || OPT) { 1795 Ptr = Ops.LHS; 1796 Idx = Ops.RHS; 1797 IdxExp = BinOp->getRHS(); 1798 } else { // int + pointer 1799 PT = BinOp->getRHS()->getType()->getAs<PointerType>(); 1800 OPT = BinOp->getRHS()->getType()->getAs<ObjCObjectPointerType>(); 1801 assert((PT || OPT) && "Invalid add expr"); 1802 Ptr = Ops.RHS; 1803 Idx = Ops.LHS; 1804 IdxExp = BinOp->getLHS(); 1805 } 1806 1807 unsigned Width = cast<llvm::IntegerType>(Idx->getType())->getBitWidth(); 1808 if (Width < CGF.LLVMPointerWidth) { 1809 // Zero or sign extend the pointer value based on whether the index is 1810 // signed or not. 1811 const llvm::Type *IdxType = CGF.IntPtrTy; 1812 if (IdxExp->getType()->isSignedIntegerType()) 1813 Idx = Builder.CreateSExt(Idx, IdxType, "idx.ext"); 1814 else 1815 Idx = Builder.CreateZExt(Idx, IdxType, "idx.ext"); 1816 } 1817 const QualType ElementType = PT ? PT->getPointeeType() : OPT->getPointeeType(); 1818 // Handle interface types, which are not represented with a concrete type. 1819 if (const ObjCObjectType *OIT = ElementType->getAs<ObjCObjectType>()) { 1820 llvm::Value *InterfaceSize = 1821 llvm::ConstantInt::get(Idx->getType(), 1822 CGF.getContext().getTypeSizeInChars(OIT).getQuantity()); 1823 Idx = Builder.CreateMul(Idx, InterfaceSize); 1824 const llvm::Type *i8Ty = llvm::Type::getInt8PtrTy(VMContext); 1825 Value *Casted = Builder.CreateBitCast(Ptr, i8Ty); 1826 Value *Res = Builder.CreateGEP(Casted, Idx, "add.ptr"); 1827 return Builder.CreateBitCast(Res, Ptr->getType()); 1828 } 1829 1830 // Explicitly handle GNU void* and function pointer arithmetic extensions. The 1831 // GNU void* casts amount to no-ops since our void* type is i8*, but this is 1832 // future proof. 1833 if (ElementType->isVoidType() || ElementType->isFunctionType()) { 1834 const llvm::Type *i8Ty = llvm::Type::getInt8PtrTy(VMContext); 1835 Value *Casted = Builder.CreateBitCast(Ptr, i8Ty); 1836 Value *Res = Builder.CreateGEP(Casted, Idx, "add.ptr"); 1837 return Builder.CreateBitCast(Res, Ptr->getType()); 1838 } 1839 1840 return Builder.CreateInBoundsGEP(Ptr, Idx, "add.ptr"); 1841} 1842 1843Value *ScalarExprEmitter::EmitSub(const BinOpInfo &Ops) { 1844 if (!isa<llvm::PointerType>(Ops.LHS->getType())) { 1845 if (Ops.Ty->hasSignedIntegerRepresentation()) { 1846 switch (CGF.getContext().getLangOptions().getSignedOverflowBehavior()) { 1847 case LangOptions::SOB_Undefined: 1848 return Builder.CreateNSWSub(Ops.LHS, Ops.RHS, "sub"); 1849 case LangOptions::SOB_Defined: 1850 return Builder.CreateSub(Ops.LHS, Ops.RHS, "sub"); 1851 case LangOptions::SOB_Trapping: 1852 return EmitOverflowCheckedBinOp(Ops); 1853 } 1854 } 1855 1856 if (Ops.LHS->getType()->isFPOrFPVectorTy()) 1857 return Builder.CreateFSub(Ops.LHS, Ops.RHS, "sub"); 1858 1859 return Builder.CreateSub(Ops.LHS, Ops.RHS, "sub"); 1860 } 1861 1862 // Must have binary (not unary) expr here. Unary pointer increment doesn't 1863 // use this path. 1864 const BinaryOperator *BinOp = cast<BinaryOperator>(Ops.E); 1865 1866 if (BinOp->getLHS()->getType()->isPointerType() && 1867 BinOp->getLHS()->getType()->getAs<PointerType>()->isVariableArrayType()) { 1868 // The amount of the addition needs to account for the VLA size for 1869 // ptr-int 1870 // The amount of the division needs to account for the VLA size for 1871 // ptr-ptr. 1872 CGF.ErrorUnsupported(BinOp, "VLA pointer subtraction"); 1873 } 1874 1875 const QualType LHSType = BinOp->getLHS()->getType(); 1876 const QualType LHSElementType = LHSType->getPointeeType(); 1877 if (!isa<llvm::PointerType>(Ops.RHS->getType())) { 1878 // pointer - int 1879 Value *Idx = Ops.RHS; 1880 unsigned Width = cast<llvm::IntegerType>(Idx->getType())->getBitWidth(); 1881 if (Width < CGF.LLVMPointerWidth) { 1882 // Zero or sign extend the pointer value based on whether the index is 1883 // signed or not. 1884 const llvm::Type *IdxType = CGF.IntPtrTy; 1885 if (BinOp->getRHS()->getType()->isSignedIntegerType()) 1886 Idx = Builder.CreateSExt(Idx, IdxType, "idx.ext"); 1887 else 1888 Idx = Builder.CreateZExt(Idx, IdxType, "idx.ext"); 1889 } 1890 Idx = Builder.CreateNeg(Idx, "sub.ptr.neg"); 1891 1892 // Handle interface types, which are not represented with a concrete type. 1893 if (const ObjCObjectType *OIT = LHSElementType->getAs<ObjCObjectType>()) { 1894 llvm::Value *InterfaceSize = 1895 llvm::ConstantInt::get(Idx->getType(), 1896 CGF.getContext(). 1897 getTypeSizeInChars(OIT).getQuantity()); 1898 Idx = Builder.CreateMul(Idx, InterfaceSize); 1899 const llvm::Type *i8Ty = llvm::Type::getInt8PtrTy(VMContext); 1900 Value *LHSCasted = Builder.CreateBitCast(Ops.LHS, i8Ty); 1901 Value *Res = Builder.CreateGEP(LHSCasted, Idx, "add.ptr"); 1902 return Builder.CreateBitCast(Res, Ops.LHS->getType()); 1903 } 1904 1905 // Explicitly handle GNU void* and function pointer arithmetic 1906 // extensions. The GNU void* casts amount to no-ops since our void* type is 1907 // i8*, but this is future proof. 1908 if (LHSElementType->isVoidType() || LHSElementType->isFunctionType()) { 1909 const llvm::Type *i8Ty = llvm::Type::getInt8PtrTy(VMContext); 1910 Value *LHSCasted = Builder.CreateBitCast(Ops.LHS, i8Ty); 1911 Value *Res = Builder.CreateGEP(LHSCasted, Idx, "sub.ptr"); 1912 return Builder.CreateBitCast(Res, Ops.LHS->getType()); 1913 } 1914 1915 return Builder.CreateInBoundsGEP(Ops.LHS, Idx, "sub.ptr"); 1916 } else { 1917 // pointer - pointer 1918 Value *LHS = Ops.LHS; 1919 Value *RHS = Ops.RHS; 1920 1921 CharUnits ElementSize; 1922 1923 // Handle GCC extension for pointer arithmetic on void* and function pointer 1924 // types. 1925 if (LHSElementType->isVoidType() || LHSElementType->isFunctionType()) { 1926 ElementSize = CharUnits::One(); 1927 } else { 1928 ElementSize = CGF.getContext().getTypeSizeInChars(LHSElementType); 1929 } 1930 1931 const llvm::Type *ResultType = ConvertType(Ops.Ty); 1932 LHS = Builder.CreatePtrToInt(LHS, ResultType, "sub.ptr.lhs.cast"); 1933 RHS = Builder.CreatePtrToInt(RHS, ResultType, "sub.ptr.rhs.cast"); 1934 Value *BytesBetween = Builder.CreateSub(LHS, RHS, "sub.ptr.sub"); 1935 1936 // Optimize out the shift for element size of 1. 1937 if (ElementSize.isOne()) 1938 return BytesBetween; 1939 1940 // Otherwise, do a full sdiv. This uses the "exact" form of sdiv, since 1941 // pointer difference in C is only defined in the case where both operands 1942 // are pointing to elements of an array. 1943 Value *BytesPerElt = 1944 llvm::ConstantInt::get(ResultType, ElementSize.getQuantity()); 1945 return Builder.CreateExactSDiv(BytesBetween, BytesPerElt, "sub.ptr.div"); 1946 } 1947} 1948 1949Value *ScalarExprEmitter::EmitShl(const BinOpInfo &Ops) { 1950 // LLVM requires the LHS and RHS to be the same type: promote or truncate the 1951 // RHS to the same size as the LHS. 1952 Value *RHS = Ops.RHS; 1953 if (Ops.LHS->getType() != RHS->getType()) 1954 RHS = Builder.CreateIntCast(RHS, Ops.LHS->getType(), false, "sh_prom"); 1955 1956 if (CGF.CatchUndefined 1957 && isa<llvm::IntegerType>(Ops.LHS->getType())) { 1958 unsigned Width = cast<llvm::IntegerType>(Ops.LHS->getType())->getBitWidth(); 1959 llvm::BasicBlock *Cont = CGF.createBasicBlock("cont"); 1960 CGF.Builder.CreateCondBr(Builder.CreateICmpULT(RHS, 1961 llvm::ConstantInt::get(RHS->getType(), Width)), 1962 Cont, CGF.getTrapBB()); 1963 CGF.EmitBlock(Cont); 1964 } 1965 1966 return Builder.CreateShl(Ops.LHS, RHS, "shl"); 1967} 1968 1969Value *ScalarExprEmitter::EmitShr(const BinOpInfo &Ops) { 1970 // LLVM requires the LHS and RHS to be the same type: promote or truncate the 1971 // RHS to the same size as the LHS. 1972 Value *RHS = Ops.RHS; 1973 if (Ops.LHS->getType() != RHS->getType()) 1974 RHS = Builder.CreateIntCast(RHS, Ops.LHS->getType(), false, "sh_prom"); 1975 1976 if (CGF.CatchUndefined 1977 && isa<llvm::IntegerType>(Ops.LHS->getType())) { 1978 unsigned Width = cast<llvm::IntegerType>(Ops.LHS->getType())->getBitWidth(); 1979 llvm::BasicBlock *Cont = CGF.createBasicBlock("cont"); 1980 CGF.Builder.CreateCondBr(Builder.CreateICmpULT(RHS, 1981 llvm::ConstantInt::get(RHS->getType(), Width)), 1982 Cont, CGF.getTrapBB()); 1983 CGF.EmitBlock(Cont); 1984 } 1985 1986 if (Ops.Ty->hasUnsignedIntegerRepresentation()) 1987 return Builder.CreateLShr(Ops.LHS, RHS, "shr"); 1988 return Builder.CreateAShr(Ops.LHS, RHS, "shr"); 1989} 1990 1991enum IntrinsicType { VCMPEQ, VCMPGT }; 1992// return corresponding comparison intrinsic for given vector type 1993static llvm::Intrinsic::ID GetIntrinsic(IntrinsicType IT, 1994 BuiltinType::Kind ElemKind) { 1995 switch (ElemKind) { 1996 default: assert(0 && "unexpected element type"); 1997 case BuiltinType::Char_U: 1998 case BuiltinType::UChar: 1999 return (IT == VCMPEQ) ? llvm::Intrinsic::ppc_altivec_vcmpequb_p : 2000 llvm::Intrinsic::ppc_altivec_vcmpgtub_p; 2001 break; 2002 case BuiltinType::Char_S: 2003 case BuiltinType::SChar: 2004 return (IT == VCMPEQ) ? llvm::Intrinsic::ppc_altivec_vcmpequb_p : 2005 llvm::Intrinsic::ppc_altivec_vcmpgtsb_p; 2006 break; 2007 case BuiltinType::UShort: 2008 return (IT == VCMPEQ) ? llvm::Intrinsic::ppc_altivec_vcmpequh_p : 2009 llvm::Intrinsic::ppc_altivec_vcmpgtuh_p; 2010 break; 2011 case BuiltinType::Short: 2012 return (IT == VCMPEQ) ? llvm::Intrinsic::ppc_altivec_vcmpequh_p : 2013 llvm::Intrinsic::ppc_altivec_vcmpgtsh_p; 2014 break; 2015 case BuiltinType::UInt: 2016 case BuiltinType::ULong: 2017 return (IT == VCMPEQ) ? llvm::Intrinsic::ppc_altivec_vcmpequw_p : 2018 llvm::Intrinsic::ppc_altivec_vcmpgtuw_p; 2019 break; 2020 case BuiltinType::Int: 2021 case BuiltinType::Long: 2022 return (IT == VCMPEQ) ? llvm::Intrinsic::ppc_altivec_vcmpequw_p : 2023 llvm::Intrinsic::ppc_altivec_vcmpgtsw_p; 2024 break; 2025 case BuiltinType::Float: 2026 return (IT == VCMPEQ) ? llvm::Intrinsic::ppc_altivec_vcmpeqfp_p : 2027 llvm::Intrinsic::ppc_altivec_vcmpgtfp_p; 2028 break; 2029 } 2030 return llvm::Intrinsic::not_intrinsic; 2031} 2032 2033Value *ScalarExprEmitter::EmitCompare(const BinaryOperator *E,unsigned UICmpOpc, 2034 unsigned SICmpOpc, unsigned FCmpOpc) { 2035 TestAndClearIgnoreResultAssign(); 2036 Value *Result; 2037 QualType LHSTy = E->getLHS()->getType(); 2038 if (const MemberPointerType *MPT = LHSTy->getAs<MemberPointerType>()) { 2039 assert(E->getOpcode() == BO_EQ || 2040 E->getOpcode() == BO_NE); 2041 Value *LHS = CGF.EmitScalarExpr(E->getLHS()); 2042 Value *RHS = CGF.EmitScalarExpr(E->getRHS()); 2043 Result = CGF.CGM.getCXXABI().EmitMemberPointerComparison( 2044 CGF, LHS, RHS, MPT, E->getOpcode() == BO_NE); 2045 } else if (!LHSTy->isAnyComplexType()) { 2046 Value *LHS = Visit(E->getLHS()); 2047 Value *RHS = Visit(E->getRHS()); 2048 2049 // If AltiVec, the comparison results in a numeric type, so we use 2050 // intrinsics comparing vectors and giving 0 or 1 as a result 2051 if (LHSTy->isVectorType() && CGF.getContext().getLangOptions().AltiVec) { 2052 // constants for mapping CR6 register bits to predicate result 2053 enum { CR6_EQ=0, CR6_EQ_REV, CR6_LT, CR6_LT_REV } CR6; 2054 2055 llvm::Intrinsic::ID ID = llvm::Intrinsic::not_intrinsic; 2056 2057 // in several cases vector arguments order will be reversed 2058 Value *FirstVecArg = LHS, 2059 *SecondVecArg = RHS; 2060 2061 QualType ElTy = LHSTy->getAs<VectorType>()->getElementType(); 2062 Type *Ty = CGF.getContext().getCanonicalType(ElTy).getTypePtr(); 2063 const BuiltinType *BTy = dyn_cast<BuiltinType>(Ty); 2064 BuiltinType::Kind ElementKind = BTy->getKind(); 2065 2066 switch(E->getOpcode()) { 2067 default: assert(0 && "is not a comparison operation"); 2068 case BO_EQ: 2069 CR6 = CR6_LT; 2070 ID = GetIntrinsic(VCMPEQ, ElementKind); 2071 break; 2072 case BO_NE: 2073 CR6 = CR6_EQ; 2074 ID = GetIntrinsic(VCMPEQ, ElementKind); 2075 break; 2076 case BO_LT: 2077 CR6 = CR6_LT; 2078 ID = GetIntrinsic(VCMPGT, ElementKind); 2079 std::swap(FirstVecArg, SecondVecArg); 2080 break; 2081 case BO_GT: 2082 CR6 = CR6_LT; 2083 ID = GetIntrinsic(VCMPGT, ElementKind); 2084 break; 2085 case BO_LE: 2086 if (ElementKind == BuiltinType::Float) { 2087 CR6 = CR6_LT; 2088 ID = llvm::Intrinsic::ppc_altivec_vcmpgefp_p; 2089 std::swap(FirstVecArg, SecondVecArg); 2090 } 2091 else { 2092 CR6 = CR6_EQ; 2093 ID = GetIntrinsic(VCMPGT, ElementKind); 2094 } 2095 break; 2096 case BO_GE: 2097 if (ElementKind == BuiltinType::Float) { 2098 CR6 = CR6_LT; 2099 ID = llvm::Intrinsic::ppc_altivec_vcmpgefp_p; 2100 } 2101 else { 2102 CR6 = CR6_EQ; 2103 ID = GetIntrinsic(VCMPGT, ElementKind); 2104 std::swap(FirstVecArg, SecondVecArg); 2105 } 2106 break; 2107 } 2108 2109 Value *CR6Param = llvm::ConstantInt::get(CGF.Int32Ty, CR6); 2110 llvm::Function *F = CGF.CGM.getIntrinsic(ID); 2111 Result = Builder.CreateCall3(F, CR6Param, FirstVecArg, SecondVecArg, ""); 2112 return EmitScalarConversion(Result, CGF.getContext().BoolTy, E->getType()); 2113 } 2114 2115 if (LHS->getType()->isFPOrFPVectorTy()) { 2116 Result = Builder.CreateFCmp((llvm::CmpInst::Predicate)FCmpOpc, 2117 LHS, RHS, "cmp"); 2118 } else if (LHSTy->hasSignedIntegerRepresentation()) { 2119 Result = Builder.CreateICmp((llvm::ICmpInst::Predicate)SICmpOpc, 2120 LHS, RHS, "cmp"); 2121 } else { 2122 // Unsigned integers and pointers. 2123 Result = Builder.CreateICmp((llvm::ICmpInst::Predicate)UICmpOpc, 2124 LHS, RHS, "cmp"); 2125 } 2126 2127 // If this is a vector comparison, sign extend the result to the appropriate 2128 // vector integer type and return it (don't convert to bool). 2129 if (LHSTy->isVectorType()) 2130 return Builder.CreateSExt(Result, ConvertType(E->getType()), "sext"); 2131 2132 } else { 2133 // Complex Comparison: can only be an equality comparison. 2134 CodeGenFunction::ComplexPairTy LHS = CGF.EmitComplexExpr(E->getLHS()); 2135 CodeGenFunction::ComplexPairTy RHS = CGF.EmitComplexExpr(E->getRHS()); 2136 2137 QualType CETy = LHSTy->getAs<ComplexType>()->getElementType(); 2138 2139 Value *ResultR, *ResultI; 2140 if (CETy->isRealFloatingType()) { 2141 ResultR = Builder.CreateFCmp((llvm::FCmpInst::Predicate)FCmpOpc, 2142 LHS.first, RHS.first, "cmp.r"); 2143 ResultI = Builder.CreateFCmp((llvm::FCmpInst::Predicate)FCmpOpc, 2144 LHS.second, RHS.second, "cmp.i"); 2145 } else { 2146 // Complex comparisons can only be equality comparisons. As such, signed 2147 // and unsigned opcodes are the same. 2148 ResultR = Builder.CreateICmp((llvm::ICmpInst::Predicate)UICmpOpc, 2149 LHS.first, RHS.first, "cmp.r"); 2150 ResultI = Builder.CreateICmp((llvm::ICmpInst::Predicate)UICmpOpc, 2151 LHS.second, RHS.second, "cmp.i"); 2152 } 2153 2154 if (E->getOpcode() == BO_EQ) { 2155 Result = Builder.CreateAnd(ResultR, ResultI, "and.ri"); 2156 } else { 2157 assert(E->getOpcode() == BO_NE && 2158 "Complex comparison other than == or != ?"); 2159 Result = Builder.CreateOr(ResultR, ResultI, "or.ri"); 2160 } 2161 } 2162 2163 return EmitScalarConversion(Result, CGF.getContext().BoolTy, E->getType()); 2164} 2165 2166Value *ScalarExprEmitter::VisitBinAssign(const BinaryOperator *E) { 2167 bool Ignore = TestAndClearIgnoreResultAssign(); 2168 2169 // __block variables need to have the rhs evaluated first, plus this should 2170 // improve codegen just a little. 2171 Value *RHS = Visit(E->getRHS()); 2172 LValue LHS = EmitCheckedLValue(E->getLHS()); 2173 2174 // Store the value into the LHS. Bit-fields are handled specially 2175 // because the result is altered by the store, i.e., [C99 6.5.16p1] 2176 // 'An assignment expression has the value of the left operand after 2177 // the assignment...'. 2178 if (LHS.isBitField()) 2179 CGF.EmitStoreThroughBitfieldLValue(RValue::get(RHS), LHS, E->getType(), 2180 &RHS); 2181 else 2182 CGF.EmitStoreThroughLValue(RValue::get(RHS), LHS, E->getType()); 2183 2184 // If the result is clearly ignored, return now. 2185 if (Ignore) 2186 return 0; 2187 2188 // The result of an assignment in C is the assigned r-value. 2189 if (!CGF.getContext().getLangOptions().CPlusPlus) 2190 return RHS; 2191 2192 // Objective-C property assignment never reloads the value following a store. 2193 if (LHS.isPropertyRef()) 2194 return RHS; 2195 2196 // If the lvalue is non-volatile, return the computed value of the assignment. 2197 if (!LHS.isVolatileQualified()) 2198 return RHS; 2199 2200 // Otherwise, reload the value. 2201 return EmitLoadOfLValue(LHS, E->getType()); 2202} 2203 2204Value *ScalarExprEmitter::VisitBinLAnd(const BinaryOperator *E) { 2205 const llvm::Type *ResTy = ConvertType(E->getType()); 2206 2207 // If we have 0 && RHS, see if we can elide RHS, if so, just return 0. 2208 // If we have 1 && X, just emit X without inserting the control flow. 2209 if (int Cond = CGF.ConstantFoldsToSimpleInteger(E->getLHS())) { 2210 if (Cond == 1) { // If we have 1 && X, just emit X. 2211 Value *RHSCond = CGF.EvaluateExprAsBool(E->getRHS()); 2212 // ZExt result to int or bool. 2213 return Builder.CreateZExtOrBitCast(RHSCond, ResTy, "land.ext"); 2214 } 2215 2216 // 0 && RHS: If it is safe, just elide the RHS, and return 0/false. 2217 if (!CGF.ContainsLabel(E->getRHS())) 2218 return llvm::Constant::getNullValue(ResTy); 2219 } 2220 2221 llvm::BasicBlock *ContBlock = CGF.createBasicBlock("land.end"); 2222 llvm::BasicBlock *RHSBlock = CGF.createBasicBlock("land.rhs"); 2223 2224 // Branch on the LHS first. If it is false, go to the failure (cont) block. 2225 CGF.EmitBranchOnBoolExpr(E->getLHS(), RHSBlock, ContBlock); 2226 2227 // Any edges into the ContBlock are now from an (indeterminate number of) 2228 // edges from this first condition. All of these values will be false. Start 2229 // setting up the PHI node in the Cont Block for this. 2230 llvm::PHINode *PN = llvm::PHINode::Create(llvm::Type::getInt1Ty(VMContext), 2231 "", ContBlock); 2232 PN->reserveOperandSpace(2); // Normal case, two inputs. 2233 for (llvm::pred_iterator PI = pred_begin(ContBlock), PE = pred_end(ContBlock); 2234 PI != PE; ++PI) 2235 PN->addIncoming(llvm::ConstantInt::getFalse(VMContext), *PI); 2236 2237 CGF.BeginConditionalBranch(); 2238 CGF.EmitBlock(RHSBlock); 2239 Value *RHSCond = CGF.EvaluateExprAsBool(E->getRHS()); 2240 CGF.EndConditionalBranch(); 2241 2242 // Reaquire the RHS block, as there may be subblocks inserted. 2243 RHSBlock = Builder.GetInsertBlock(); 2244 2245 // Emit an unconditional branch from this block to ContBlock. Insert an entry 2246 // into the phi node for the edge with the value of RHSCond. 2247 CGF.EmitBlock(ContBlock); 2248 PN->addIncoming(RHSCond, RHSBlock); 2249 2250 // ZExt result to int. 2251 return Builder.CreateZExtOrBitCast(PN, ResTy, "land.ext"); 2252} 2253 2254Value *ScalarExprEmitter::VisitBinLOr(const BinaryOperator *E) { 2255 const llvm::Type *ResTy = ConvertType(E->getType()); 2256 2257 // If we have 1 || RHS, see if we can elide RHS, if so, just return 1. 2258 // If we have 0 || X, just emit X without inserting the control flow. 2259 if (int Cond = CGF.ConstantFoldsToSimpleInteger(E->getLHS())) { 2260 if (Cond == -1) { // If we have 0 || X, just emit X. 2261 Value *RHSCond = CGF.EvaluateExprAsBool(E->getRHS()); 2262 // ZExt result to int or bool. 2263 return Builder.CreateZExtOrBitCast(RHSCond, ResTy, "lor.ext"); 2264 } 2265 2266 // 1 || RHS: If it is safe, just elide the RHS, and return 1/true. 2267 if (!CGF.ContainsLabel(E->getRHS())) 2268 return llvm::ConstantInt::get(ResTy, 1); 2269 } 2270 2271 llvm::BasicBlock *ContBlock = CGF.createBasicBlock("lor.end"); 2272 llvm::BasicBlock *RHSBlock = CGF.createBasicBlock("lor.rhs"); 2273 2274 // Branch on the LHS first. If it is true, go to the success (cont) block. 2275 CGF.EmitBranchOnBoolExpr(E->getLHS(), ContBlock, RHSBlock); 2276 2277 // Any edges into the ContBlock are now from an (indeterminate number of) 2278 // edges from this first condition. All of these values will be true. Start 2279 // setting up the PHI node in the Cont Block for this. 2280 llvm::PHINode *PN = llvm::PHINode::Create(llvm::Type::getInt1Ty(VMContext), 2281 "", ContBlock); 2282 PN->reserveOperandSpace(2); // Normal case, two inputs. 2283 for (llvm::pred_iterator PI = pred_begin(ContBlock), PE = pred_end(ContBlock); 2284 PI != PE; ++PI) 2285 PN->addIncoming(llvm::ConstantInt::getTrue(VMContext), *PI); 2286 2287 CGF.BeginConditionalBranch(); 2288 2289 // Emit the RHS condition as a bool value. 2290 CGF.EmitBlock(RHSBlock); 2291 Value *RHSCond = CGF.EvaluateExprAsBool(E->getRHS()); 2292 2293 CGF.EndConditionalBranch(); 2294 2295 // Reaquire the RHS block, as there may be subblocks inserted. 2296 RHSBlock = Builder.GetInsertBlock(); 2297 2298 // Emit an unconditional branch from this block to ContBlock. Insert an entry 2299 // into the phi node for the edge with the value of RHSCond. 2300 CGF.EmitBlock(ContBlock); 2301 PN->addIncoming(RHSCond, RHSBlock); 2302 2303 // ZExt result to int. 2304 return Builder.CreateZExtOrBitCast(PN, ResTy, "lor.ext"); 2305} 2306 2307Value *ScalarExprEmitter::VisitBinComma(const BinaryOperator *E) { 2308 CGF.EmitIgnoredExpr(E->getLHS()); 2309 CGF.EnsureInsertPoint(); 2310 return Visit(E->getRHS()); 2311} 2312 2313//===----------------------------------------------------------------------===// 2314// Other Operators 2315//===----------------------------------------------------------------------===// 2316 2317/// isCheapEnoughToEvaluateUnconditionally - Return true if the specified 2318/// expression is cheap enough and side-effect-free enough to evaluate 2319/// unconditionally instead of conditionally. This is used to convert control 2320/// flow into selects in some cases. 2321static bool isCheapEnoughToEvaluateUnconditionally(const Expr *E, 2322 CodeGenFunction &CGF) { 2323 if (const ParenExpr *PE = dyn_cast<ParenExpr>(E)) 2324 return isCheapEnoughToEvaluateUnconditionally(PE->getSubExpr(), CGF); 2325 2326 // TODO: Allow anything we can constant fold to an integer or fp constant. 2327 if (isa<IntegerLiteral>(E) || isa<CharacterLiteral>(E) || 2328 isa<FloatingLiteral>(E)) 2329 return true; 2330 2331 // Non-volatile automatic variables too, to get "cond ? X : Y" where 2332 // X and Y are local variables. 2333 if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(E)) 2334 if (const VarDecl *VD = dyn_cast<VarDecl>(DRE->getDecl())) 2335 if (VD->hasLocalStorage() && !(CGF.getContext() 2336 .getCanonicalType(VD->getType()) 2337 .isVolatileQualified())) 2338 return true; 2339 2340 return false; 2341} 2342 2343 2344Value *ScalarExprEmitter:: 2345VisitConditionalOperator(const ConditionalOperator *E) { 2346 TestAndClearIgnoreResultAssign(); 2347 // If the condition constant folds and can be elided, try to avoid emitting 2348 // the condition and the dead arm. 2349 if (int Cond = CGF.ConstantFoldsToSimpleInteger(E->getCond())){ 2350 Expr *Live = E->getLHS(), *Dead = E->getRHS(); 2351 if (Cond == -1) 2352 std::swap(Live, Dead); 2353 2354 // If the dead side doesn't have labels we need, and if the Live side isn't 2355 // the gnu missing ?: extension (which we could handle, but don't bother 2356 // to), just emit the Live part. 2357 if ((!Dead || !CGF.ContainsLabel(Dead)) && // No labels in dead part 2358 Live) // Live part isn't missing. 2359 return Visit(Live); 2360 } 2361 2362 // OpenCL: If the condition is a vector, we can treat this condition like 2363 // the select function. 2364 if (CGF.getContext().getLangOptions().OpenCL 2365 && E->getCond()->getType()->isVectorType()) { 2366 llvm::Value *CondV = CGF.EmitScalarExpr(E->getCond()); 2367 llvm::Value *LHS = Visit(E->getLHS()); 2368 llvm::Value *RHS = Visit(E->getRHS()); 2369 2370 const llvm::Type *condType = ConvertType(E->getCond()->getType()); 2371 const llvm::VectorType *vecTy = cast<llvm::VectorType>(condType); 2372 2373 unsigned numElem = vecTy->getNumElements(); 2374 const llvm::Type *elemType = vecTy->getElementType(); 2375 2376 std::vector<llvm::Constant*> Zvals; 2377 for (unsigned i = 0; i < numElem; ++i) 2378 Zvals.push_back(llvm::ConstantInt::get(elemType,0)); 2379 2380 llvm::Value *zeroVec = llvm::ConstantVector::get(Zvals); 2381 llvm::Value *TestMSB = Builder.CreateICmpSLT(CondV, zeroVec); 2382 llvm::Value *tmp = Builder.CreateSExt(TestMSB, 2383 llvm::VectorType::get(elemType, 2384 numElem), 2385 "sext"); 2386 llvm::Value *tmp2 = Builder.CreateNot(tmp); 2387 2388 // Cast float to int to perform ANDs if necessary. 2389 llvm::Value *RHSTmp = RHS; 2390 llvm::Value *LHSTmp = LHS; 2391 bool wasCast = false; 2392 const llvm::VectorType *rhsVTy = cast<llvm::VectorType>(RHS->getType()); 2393 if (rhsVTy->getElementType()->isFloatTy()) { 2394 RHSTmp = Builder.CreateBitCast(RHS, tmp2->getType()); 2395 LHSTmp = Builder.CreateBitCast(LHS, tmp->getType()); 2396 wasCast = true; 2397 } 2398 2399 llvm::Value *tmp3 = Builder.CreateAnd(RHSTmp, tmp2); 2400 llvm::Value *tmp4 = Builder.CreateAnd(LHSTmp, tmp); 2401 llvm::Value *tmp5 = Builder.CreateOr(tmp3, tmp4, "cond"); 2402 if (wasCast) 2403 tmp5 = Builder.CreateBitCast(tmp5, RHS->getType()); 2404 2405 return tmp5; 2406 } 2407 2408 // If this is a really simple expression (like x ? 4 : 5), emit this as a 2409 // select instead of as control flow. We can only do this if it is cheap and 2410 // safe to evaluate the LHS and RHS unconditionally. 2411 if (E->getLHS() && isCheapEnoughToEvaluateUnconditionally(E->getLHS(), 2412 CGF) && 2413 isCheapEnoughToEvaluateUnconditionally(E->getRHS(), CGF)) { 2414 llvm::Value *CondV = CGF.EvaluateExprAsBool(E->getCond()); 2415 llvm::Value *LHS = Visit(E->getLHS()); 2416 llvm::Value *RHS = Visit(E->getRHS()); 2417 return Builder.CreateSelect(CondV, LHS, RHS, "cond"); 2418 } 2419 2420 llvm::BasicBlock *LHSBlock = CGF.createBasicBlock("cond.true"); 2421 llvm::BasicBlock *RHSBlock = CGF.createBasicBlock("cond.false"); 2422 llvm::BasicBlock *ContBlock = CGF.createBasicBlock("cond.end"); 2423 2424 // If we don't have the GNU missing condition extension, emit a branch on bool 2425 // the normal way. 2426 if (E->getLHS()) { 2427 // Otherwise, just use EmitBranchOnBoolExpr to get small and simple code for 2428 // the branch on bool. 2429 CGF.EmitBranchOnBoolExpr(E->getCond(), LHSBlock, RHSBlock); 2430 } else { 2431 // Otherwise, for the ?: extension, evaluate the conditional and then 2432 // convert it to bool the hard way. We do this explicitly because we need 2433 // the unconverted value for the missing middle value of the ?:. 2434 Expr *save = E->getSAVE(); 2435 assert(save && "VisitConditionalOperator - save is null"); 2436 // Intentianlly not doing direct assignment to ConditionalSaveExprs[save] !! 2437 Value *SaveVal = CGF.EmitScalarExpr(save); 2438 CGF.ConditionalSaveExprs[save] = SaveVal; 2439 Value *CondVal = Visit(E->getCond()); 2440 // In some cases, EmitScalarConversion will delete the "CondVal" expression 2441 // if there are no extra uses (an optimization). Inhibit this by making an 2442 // extra dead use, because we're going to add a use of CondVal later. We 2443 // don't use the builder for this, because we don't want it to get optimized 2444 // away. This leaves dead code, but the ?: extension isn't common. 2445 new llvm::BitCastInst(CondVal, CondVal->getType(), "dummy?:holder", 2446 Builder.GetInsertBlock()); 2447 2448 Value *CondBoolVal = 2449 CGF.EmitScalarConversion(CondVal, E->getCond()->getType(), 2450 CGF.getContext().BoolTy); 2451 Builder.CreateCondBr(CondBoolVal, LHSBlock, RHSBlock); 2452 } 2453 2454 CGF.BeginConditionalBranch(); 2455 CGF.EmitBlock(LHSBlock); 2456 2457 // Handle the GNU extension for missing LHS. 2458 Value *LHS = Visit(E->getTrueExpr()); 2459 2460 CGF.EndConditionalBranch(); 2461 LHSBlock = Builder.GetInsertBlock(); 2462 CGF.EmitBranch(ContBlock); 2463 2464 CGF.BeginConditionalBranch(); 2465 CGF.EmitBlock(RHSBlock); 2466 2467 Value *RHS = Visit(E->getRHS()); 2468 CGF.EndConditionalBranch(); 2469 RHSBlock = Builder.GetInsertBlock(); 2470 CGF.EmitBranch(ContBlock); 2471 2472 CGF.EmitBlock(ContBlock); 2473 2474 // If the LHS or RHS is a throw expression, it will be legitimately null. 2475 if (!LHS) 2476 return RHS; 2477 if (!RHS) 2478 return LHS; 2479 2480 // Create a PHI node for the real part. 2481 llvm::PHINode *PN = Builder.CreatePHI(LHS->getType(), "cond"); 2482 PN->reserveOperandSpace(2); 2483 PN->addIncoming(LHS, LHSBlock); 2484 PN->addIncoming(RHS, RHSBlock); 2485 return PN; 2486} 2487 2488Value *ScalarExprEmitter::VisitChooseExpr(ChooseExpr *E) { 2489 return Visit(E->getChosenSubExpr(CGF.getContext())); 2490} 2491 2492Value *ScalarExprEmitter::VisitVAArgExpr(VAArgExpr *VE) { 2493 llvm::Value *ArgValue = CGF.EmitVAListRef(VE->getSubExpr()); 2494 llvm::Value *ArgPtr = CGF.EmitVAArg(ArgValue, VE->getType()); 2495 2496 // If EmitVAArg fails, we fall back to the LLVM instruction. 2497 if (!ArgPtr) 2498 return Builder.CreateVAArg(ArgValue, ConvertType(VE->getType())); 2499 2500 // FIXME Volatility. 2501 return Builder.CreateLoad(ArgPtr); 2502} 2503 2504Value *ScalarExprEmitter::VisitBlockExpr(const BlockExpr *BE) { 2505 return CGF.BuildBlockLiteralTmp(BE); 2506} 2507 2508//===----------------------------------------------------------------------===// 2509// Entry Point into this File 2510//===----------------------------------------------------------------------===// 2511 2512/// EmitScalarExpr - Emit the computation of the specified expression of scalar 2513/// type, ignoring the result. 2514Value *CodeGenFunction::EmitScalarExpr(const Expr *E, bool IgnoreResultAssign) { 2515 assert(E && !hasAggregateLLVMType(E->getType()) && 2516 "Invalid scalar expression to emit"); 2517 2518 return ScalarExprEmitter(*this, IgnoreResultAssign) 2519 .Visit(const_cast<Expr*>(E)); 2520} 2521 2522/// EmitScalarConversion - Emit a conversion from the specified type to the 2523/// specified destination type, both of which are LLVM scalar types. 2524Value *CodeGenFunction::EmitScalarConversion(Value *Src, QualType SrcTy, 2525 QualType DstTy) { 2526 assert(!hasAggregateLLVMType(SrcTy) && !hasAggregateLLVMType(DstTy) && 2527 "Invalid scalar expression to emit"); 2528 return ScalarExprEmitter(*this).EmitScalarConversion(Src, SrcTy, DstTy); 2529} 2530 2531/// EmitComplexToScalarConversion - Emit a conversion from the specified complex 2532/// type to the specified destination type, where the destination type is an 2533/// LLVM scalar type. 2534Value *CodeGenFunction::EmitComplexToScalarConversion(ComplexPairTy Src, 2535 QualType SrcTy, 2536 QualType DstTy) { 2537 assert(SrcTy->isAnyComplexType() && !hasAggregateLLVMType(DstTy) && 2538 "Invalid complex -> scalar conversion"); 2539 return ScalarExprEmitter(*this).EmitComplexToScalarConversion(Src, SrcTy, 2540 DstTy); 2541} 2542 2543 2544llvm::Value *CodeGenFunction:: 2545EmitScalarPrePostIncDec(const UnaryOperator *E, LValue LV, 2546 bool isInc, bool isPre) { 2547 return ScalarExprEmitter(*this).EmitScalarPrePostIncDec(E, LV, isInc, isPre); 2548} 2549 2550LValue CodeGenFunction::EmitObjCIsaExpr(const ObjCIsaExpr *E) { 2551 llvm::Value *V; 2552 // object->isa or (*object).isa 2553 // Generate code as for: *(Class*)object 2554 // build Class* type 2555 const llvm::Type *ClassPtrTy = ConvertType(E->getType()); 2556 2557 Expr *BaseExpr = E->getBase(); 2558 if (BaseExpr->isRValue()) { 2559 V = CreateTempAlloca(ClassPtrTy, "resval"); 2560 llvm::Value *Src = EmitScalarExpr(BaseExpr); 2561 Builder.CreateStore(Src, V); 2562 V = ScalarExprEmitter(*this).EmitLoadOfLValue( 2563 MakeAddrLValue(V, E->getType()), E->getType()); 2564 } else { 2565 if (E->isArrow()) 2566 V = ScalarExprEmitter(*this).EmitLoadOfLValue(BaseExpr); 2567 else 2568 V = EmitLValue(BaseExpr).getAddress(); 2569 } 2570 2571 // build Class* type 2572 ClassPtrTy = ClassPtrTy->getPointerTo(); 2573 V = Builder.CreateBitCast(V, ClassPtrTy); 2574 return MakeAddrLValue(V, E->getType()); 2575} 2576 2577 2578LValue CodeGenFunction::EmitCompoundAssignmentLValue( 2579 const CompoundAssignOperator *E) { 2580 ScalarExprEmitter Scalar(*this); 2581 Value *Result = 0; 2582 switch (E->getOpcode()) { 2583#define COMPOUND_OP(Op) \ 2584 case BO_##Op##Assign: \ 2585 return Scalar.EmitCompoundAssignLValue(E, &ScalarExprEmitter::Emit##Op, \ 2586 Result) 2587 COMPOUND_OP(Mul); 2588 COMPOUND_OP(Div); 2589 COMPOUND_OP(Rem); 2590 COMPOUND_OP(Add); 2591 COMPOUND_OP(Sub); 2592 COMPOUND_OP(Shl); 2593 COMPOUND_OP(Shr); 2594 COMPOUND_OP(And); 2595 COMPOUND_OP(Xor); 2596 COMPOUND_OP(Or); 2597#undef COMPOUND_OP 2598 2599 case BO_PtrMemD: 2600 case BO_PtrMemI: 2601 case BO_Mul: 2602 case BO_Div: 2603 case BO_Rem: 2604 case BO_Add: 2605 case BO_Sub: 2606 case BO_Shl: 2607 case BO_Shr: 2608 case BO_LT: 2609 case BO_GT: 2610 case BO_LE: 2611 case BO_GE: 2612 case BO_EQ: 2613 case BO_NE: 2614 case BO_And: 2615 case BO_Xor: 2616 case BO_Or: 2617 case BO_LAnd: 2618 case BO_LOr: 2619 case BO_Assign: 2620 case BO_Comma: 2621 assert(false && "Not valid compound assignment operators"); 2622 break; 2623 } 2624 2625 llvm_unreachable("Unhandled compound assignment operator"); 2626} 2627