CGExprScalar.cpp revision d4b9ee3b6ad82843c55909d6499232fce530113e
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 return Builder.CreateIsNotNull(V, "tobool"); 144 } 145 146 //===--------------------------------------------------------------------===// 147 // Visitor Methods 148 //===--------------------------------------------------------------------===// 149 150 Value *Visit(Expr *E) { 151 return StmtVisitor<ScalarExprEmitter, Value*>::Visit(E); 152 } 153 154 Value *VisitStmt(Stmt *S) { 155 S->dump(CGF.getContext().getSourceManager()); 156 assert(0 && "Stmt can't have complex result type!"); 157 return 0; 158 } 159 Value *VisitExpr(Expr *S); 160 161 Value *VisitParenExpr(ParenExpr *PE) { 162 return Visit(PE->getSubExpr()); 163 } 164 Value *VisitGenericSelectionExpr(GenericSelectionExpr *GE) { 165 return Visit(GE->getResultExpr()); 166 } 167 168 // Leaves. 169 Value *VisitIntegerLiteral(const IntegerLiteral *E) { 170 return Builder.getInt(E->getValue()); 171 } 172 Value *VisitFloatingLiteral(const FloatingLiteral *E) { 173 return llvm::ConstantFP::get(VMContext, E->getValue()); 174 } 175 Value *VisitCharacterLiteral(const CharacterLiteral *E) { 176 return llvm::ConstantInt::get(ConvertType(E->getType()), E->getValue()); 177 } 178 Value *VisitCXXBoolLiteralExpr(const CXXBoolLiteralExpr *E) { 179 return llvm::ConstantInt::get(ConvertType(E->getType()), E->getValue()); 180 } 181 Value *VisitCXXScalarValueInitExpr(const CXXScalarValueInitExpr *E) { 182 return EmitNullValue(E->getType()); 183 } 184 Value *VisitGNUNullExpr(const GNUNullExpr *E) { 185 return EmitNullValue(E->getType()); 186 } 187 Value *VisitOffsetOfExpr(OffsetOfExpr *E); 188 Value *VisitUnaryExprOrTypeTraitExpr(const UnaryExprOrTypeTraitExpr *E); 189 Value *VisitAddrLabelExpr(const AddrLabelExpr *E) { 190 llvm::Value *V = CGF.GetAddrOfLabel(E->getLabel()); 191 return Builder.CreateBitCast(V, ConvertType(E->getType())); 192 } 193 194 Value *VisitSizeOfPackExpr(SizeOfPackExpr *E) { 195 return llvm::ConstantInt::get(ConvertType(E->getType()),E->getPackLength()); 196 } 197 198 Value *VisitOpaqueValueExpr(OpaqueValueExpr *E) { 199 if (E->isGLValue()) 200 return EmitLoadOfLValue(CGF.getOpaqueLValueMapping(E), E->getType()); 201 202 // Otherwise, assume the mapping is the scalar directly. 203 return CGF.getOpaqueRValueMapping(E).getScalarVal(); 204 } 205 206 // l-values. 207 Value *VisitDeclRefExpr(DeclRefExpr *E) { 208 Expr::EvalResult Result; 209 if (!E->Evaluate(Result, CGF.getContext())) 210 return EmitLoadOfLValue(E); 211 212 assert(!Result.HasSideEffects && "Constant declref with side-effect?!"); 213 214 llvm::Constant *C; 215 if (Result.Val.isInt()) 216 C = Builder.getInt(Result.Val.getInt()); 217 else if (Result.Val.isFloat()) 218 C = llvm::ConstantFP::get(VMContext, Result.Val.getFloat()); 219 else 220 return EmitLoadOfLValue(E); 221 222 // Make sure we emit a debug reference to the global variable. 223 if (VarDecl *VD = dyn_cast<VarDecl>(E->getDecl())) { 224 if (!CGF.getContext().DeclMustBeEmitted(VD)) 225 CGF.EmitDeclRefExprDbgValue(E, C); 226 } else if (isa<EnumConstantDecl>(E->getDecl())) { 227 CGF.EmitDeclRefExprDbgValue(E, C); 228 } 229 230 return C; 231 } 232 Value *VisitObjCSelectorExpr(ObjCSelectorExpr *E) { 233 return CGF.EmitObjCSelectorExpr(E); 234 } 235 Value *VisitObjCProtocolExpr(ObjCProtocolExpr *E) { 236 return CGF.EmitObjCProtocolExpr(E); 237 } 238 Value *VisitObjCIvarRefExpr(ObjCIvarRefExpr *E) { 239 return EmitLoadOfLValue(E); 240 } 241 Value *VisitObjCPropertyRefExpr(ObjCPropertyRefExpr *E) { 242 assert(E->getObjectKind() == OK_Ordinary && 243 "reached property reference without lvalue-to-rvalue"); 244 return EmitLoadOfLValue(E); 245 } 246 Value *VisitObjCMessageExpr(ObjCMessageExpr *E) { 247 if (E->getMethodDecl() && 248 E->getMethodDecl()->getResultType()->isReferenceType()) 249 return EmitLoadOfLValue(E); 250 return CGF.EmitObjCMessageExpr(E).getScalarVal(); 251 } 252 253 Value *VisitObjCIsaExpr(ObjCIsaExpr *E) { 254 LValue LV = CGF.EmitObjCIsaExpr(E); 255 Value *V = CGF.EmitLoadOfLValue(LV, E->getType()).getScalarVal(); 256 return V; 257 } 258 259 Value *VisitArraySubscriptExpr(ArraySubscriptExpr *E); 260 Value *VisitShuffleVectorExpr(ShuffleVectorExpr *E); 261 Value *VisitMemberExpr(MemberExpr *E); 262 Value *VisitExtVectorElementExpr(Expr *E) { return EmitLoadOfLValue(E); } 263 Value *VisitCompoundLiteralExpr(CompoundLiteralExpr *E) { 264 return EmitLoadOfLValue(E); 265 } 266 267 Value *VisitInitListExpr(InitListExpr *E); 268 269 Value *VisitImplicitValueInitExpr(const ImplicitValueInitExpr *E) { 270 return CGF.CGM.EmitNullConstant(E->getType()); 271 } 272 Value *VisitCastExpr(CastExpr *E) { 273 // Make sure to evaluate VLA bounds now so that we have them for later. 274 if (E->getType()->isVariablyModifiedType()) 275 CGF.EmitVLASize(E->getType()); 276 277 return EmitCastExpr(E); 278 } 279 Value *EmitCastExpr(CastExpr *E); 280 281 Value *VisitCallExpr(const CallExpr *E) { 282 if (E->getCallReturnType()->isReferenceType()) 283 return EmitLoadOfLValue(E); 284 285 return CGF.EmitCallExpr(E).getScalarVal(); 286 } 287 288 Value *VisitStmtExpr(const StmtExpr *E); 289 290 Value *VisitBlockDeclRefExpr(const BlockDeclRefExpr *E); 291 292 // Unary Operators. 293 Value *VisitUnaryPostDec(const UnaryOperator *E) { 294 LValue LV = EmitLValue(E->getSubExpr()); 295 return EmitScalarPrePostIncDec(E, LV, false, false); 296 } 297 Value *VisitUnaryPostInc(const UnaryOperator *E) { 298 LValue LV = EmitLValue(E->getSubExpr()); 299 return EmitScalarPrePostIncDec(E, LV, true, false); 300 } 301 Value *VisitUnaryPreDec(const UnaryOperator *E) { 302 LValue LV = EmitLValue(E->getSubExpr()); 303 return EmitScalarPrePostIncDec(E, LV, false, true); 304 } 305 Value *VisitUnaryPreInc(const UnaryOperator *E) { 306 LValue LV = EmitLValue(E->getSubExpr()); 307 return EmitScalarPrePostIncDec(E, LV, true, true); 308 } 309 310 llvm::Value *EmitAddConsiderOverflowBehavior(const UnaryOperator *E, 311 llvm::Value *InVal, 312 llvm::Value *NextVal, 313 bool IsInc); 314 315 llvm::Value *EmitScalarPrePostIncDec(const UnaryOperator *E, LValue LV, 316 bool isInc, bool isPre); 317 318 319 Value *VisitUnaryAddrOf(const UnaryOperator *E) { 320 if (isa<MemberPointerType>(E->getType())) // never sugared 321 return CGF.CGM.getMemberPointerConstant(E); 322 323 return EmitLValue(E->getSubExpr()).getAddress(); 324 } 325 Value *VisitUnaryDeref(const UnaryOperator *E) { 326 if (E->getType()->isVoidType()) 327 return Visit(E->getSubExpr()); // the actual value should be unused 328 return EmitLoadOfLValue(E); 329 } 330 Value *VisitUnaryPlus(const UnaryOperator *E) { 331 // This differs from gcc, though, most likely due to a bug in gcc. 332 TestAndClearIgnoreResultAssign(); 333 return Visit(E->getSubExpr()); 334 } 335 Value *VisitUnaryMinus (const UnaryOperator *E); 336 Value *VisitUnaryNot (const UnaryOperator *E); 337 Value *VisitUnaryLNot (const UnaryOperator *E); 338 Value *VisitUnaryReal (const UnaryOperator *E); 339 Value *VisitUnaryImag (const UnaryOperator *E); 340 Value *VisitUnaryExtension(const UnaryOperator *E) { 341 return Visit(E->getSubExpr()); 342 } 343 344 // C++ 345 Value *VisitCXXDefaultArgExpr(CXXDefaultArgExpr *DAE) { 346 return Visit(DAE->getExpr()); 347 } 348 Value *VisitCXXThisExpr(CXXThisExpr *TE) { 349 return CGF.LoadCXXThis(); 350 } 351 352 Value *VisitExprWithCleanups(ExprWithCleanups *E) { 353 return CGF.EmitExprWithCleanups(E).getScalarVal(); 354 } 355 Value *VisitCXXNewExpr(const CXXNewExpr *E) { 356 return CGF.EmitCXXNewExpr(E); 357 } 358 Value *VisitCXXDeleteExpr(const CXXDeleteExpr *E) { 359 CGF.EmitCXXDeleteExpr(E); 360 return 0; 361 } 362 Value *VisitUnaryTypeTraitExpr(const UnaryTypeTraitExpr *E) { 363 return Builder.getInt1(E->getValue()); 364 } 365 366 Value *VisitBinaryTypeTraitExpr(const BinaryTypeTraitExpr *E) { 367 return llvm::ConstantInt::get(ConvertType(E->getType()), E->getValue()); 368 } 369 370 Value *VisitArrayTypeTraitExpr(const ArrayTypeTraitExpr *E) { 371 return llvm::ConstantInt::get(Builder.getInt32Ty(), E->getValue()); 372 } 373 374 Value *VisitExpressionTraitExpr(const ExpressionTraitExpr *E) { 375 return llvm::ConstantInt::get(Builder.getInt1Ty(), E->getValue()); 376 } 377 378 Value *VisitCXXPseudoDestructorExpr(const CXXPseudoDestructorExpr *E) { 379 // C++ [expr.pseudo]p1: 380 // The result shall only be used as the operand for the function call 381 // operator (), and the result of such a call has type void. The only 382 // effect is the evaluation of the postfix-expression before the dot or 383 // arrow. 384 CGF.EmitScalarExpr(E->getBase()); 385 return 0; 386 } 387 388 Value *VisitCXXNullPtrLiteralExpr(const CXXNullPtrLiteralExpr *E) { 389 return EmitNullValue(E->getType()); 390 } 391 392 Value *VisitCXXThrowExpr(const CXXThrowExpr *E) { 393 CGF.EmitCXXThrowExpr(E); 394 return 0; 395 } 396 397 Value *VisitCXXNoexceptExpr(const CXXNoexceptExpr *E) { 398 return Builder.getInt1(E->getValue()); 399 } 400 401 // Binary Operators. 402 Value *EmitMul(const BinOpInfo &Ops) { 403 if (Ops.Ty->isSignedIntegerType()) { 404 switch (CGF.getContext().getLangOptions().getSignedOverflowBehavior()) { 405 case LangOptions::SOB_Undefined: 406 return Builder.CreateNSWMul(Ops.LHS, Ops.RHS, "mul"); 407 case LangOptions::SOB_Defined: 408 return Builder.CreateMul(Ops.LHS, Ops.RHS, "mul"); 409 case LangOptions::SOB_Trapping: 410 return EmitOverflowCheckedBinOp(Ops); 411 } 412 } 413 414 if (Ops.LHS->getType()->isFPOrFPVectorTy()) 415 return Builder.CreateFMul(Ops.LHS, Ops.RHS, "mul"); 416 return Builder.CreateMul(Ops.LHS, Ops.RHS, "mul"); 417 } 418 bool isTrapvOverflowBehavior() { 419 return CGF.getContext().getLangOptions().getSignedOverflowBehavior() 420 == LangOptions::SOB_Trapping; 421 } 422 /// Create a binary op that checks for overflow. 423 /// Currently only supports +, - and *. 424 Value *EmitOverflowCheckedBinOp(const BinOpInfo &Ops); 425 // Emit the overflow BB when -ftrapv option is activated. 426 void EmitOverflowBB(llvm::BasicBlock *overflowBB) { 427 Builder.SetInsertPoint(overflowBB); 428 llvm::Function *Trap = CGF.CGM.getIntrinsic(llvm::Intrinsic::trap); 429 Builder.CreateCall(Trap); 430 Builder.CreateUnreachable(); 431 } 432 // Check for undefined division and modulus behaviors. 433 void EmitUndefinedBehaviorIntegerDivAndRemCheck(const BinOpInfo &Ops, 434 llvm::Value *Zero,bool isDiv); 435 Value *EmitDiv(const BinOpInfo &Ops); 436 Value *EmitRem(const BinOpInfo &Ops); 437 Value *EmitAdd(const BinOpInfo &Ops); 438 Value *EmitSub(const BinOpInfo &Ops); 439 Value *EmitShl(const BinOpInfo &Ops); 440 Value *EmitShr(const BinOpInfo &Ops); 441 Value *EmitAnd(const BinOpInfo &Ops) { 442 return Builder.CreateAnd(Ops.LHS, Ops.RHS, "and"); 443 } 444 Value *EmitXor(const BinOpInfo &Ops) { 445 return Builder.CreateXor(Ops.LHS, Ops.RHS, "xor"); 446 } 447 Value *EmitOr (const BinOpInfo &Ops) { 448 return Builder.CreateOr(Ops.LHS, Ops.RHS, "or"); 449 } 450 451 BinOpInfo EmitBinOps(const BinaryOperator *E); 452 LValue EmitCompoundAssignLValue(const CompoundAssignOperator *E, 453 Value *(ScalarExprEmitter::*F)(const BinOpInfo &), 454 Value *&Result); 455 456 Value *EmitCompoundAssign(const CompoundAssignOperator *E, 457 Value *(ScalarExprEmitter::*F)(const BinOpInfo &)); 458 459 // Binary operators and binary compound assignment operators. 460#define HANDLEBINOP(OP) \ 461 Value *VisitBin ## OP(const BinaryOperator *E) { \ 462 return Emit ## OP(EmitBinOps(E)); \ 463 } \ 464 Value *VisitBin ## OP ## Assign(const CompoundAssignOperator *E) { \ 465 return EmitCompoundAssign(E, &ScalarExprEmitter::Emit ## OP); \ 466 } 467 HANDLEBINOP(Mul) 468 HANDLEBINOP(Div) 469 HANDLEBINOP(Rem) 470 HANDLEBINOP(Add) 471 HANDLEBINOP(Sub) 472 HANDLEBINOP(Shl) 473 HANDLEBINOP(Shr) 474 HANDLEBINOP(And) 475 HANDLEBINOP(Xor) 476 HANDLEBINOP(Or) 477#undef HANDLEBINOP 478 479 // Comparisons. 480 Value *EmitCompare(const BinaryOperator *E, unsigned UICmpOpc, 481 unsigned SICmpOpc, unsigned FCmpOpc); 482#define VISITCOMP(CODE, UI, SI, FP) \ 483 Value *VisitBin##CODE(const BinaryOperator *E) { \ 484 return EmitCompare(E, llvm::ICmpInst::UI, llvm::ICmpInst::SI, \ 485 llvm::FCmpInst::FP); } 486 VISITCOMP(LT, ICMP_ULT, ICMP_SLT, FCMP_OLT) 487 VISITCOMP(GT, ICMP_UGT, ICMP_SGT, FCMP_OGT) 488 VISITCOMP(LE, ICMP_ULE, ICMP_SLE, FCMP_OLE) 489 VISITCOMP(GE, ICMP_UGE, ICMP_SGE, FCMP_OGE) 490 VISITCOMP(EQ, ICMP_EQ , ICMP_EQ , FCMP_OEQ) 491 VISITCOMP(NE, ICMP_NE , ICMP_NE , FCMP_UNE) 492#undef VISITCOMP 493 494 Value *VisitBinAssign (const BinaryOperator *E); 495 496 Value *VisitBinLAnd (const BinaryOperator *E); 497 Value *VisitBinLOr (const BinaryOperator *E); 498 Value *VisitBinComma (const BinaryOperator *E); 499 500 Value *VisitBinPtrMemD(const Expr *E) { return EmitLoadOfLValue(E); } 501 Value *VisitBinPtrMemI(const Expr *E) { return EmitLoadOfLValue(E); } 502 503 // Other Operators. 504 Value *VisitBlockExpr(const BlockExpr *BE); 505 Value *VisitAbstractConditionalOperator(const AbstractConditionalOperator *); 506 Value *VisitChooseExpr(ChooseExpr *CE); 507 Value *VisitVAArgExpr(VAArgExpr *VE); 508 Value *VisitObjCStringLiteral(const ObjCStringLiteral *E) { 509 return CGF.EmitObjCStringLiteral(E); 510 } 511}; 512} // end anonymous namespace. 513 514//===----------------------------------------------------------------------===// 515// Utilities 516//===----------------------------------------------------------------------===// 517 518/// EmitConversionToBool - Convert the specified expression value to a 519/// boolean (i1) truth value. This is equivalent to "Val != 0". 520Value *ScalarExprEmitter::EmitConversionToBool(Value *Src, QualType SrcType) { 521 assert(SrcType.isCanonical() && "EmitScalarConversion strips typedefs"); 522 523 if (SrcType->isRealFloatingType()) 524 return EmitFloatToBoolConversion(Src); 525 526 if (const MemberPointerType *MPT = dyn_cast<MemberPointerType>(SrcType)) 527 return CGF.CGM.getCXXABI().EmitMemberPointerIsNotNull(CGF, Src, MPT); 528 529 assert((SrcType->isIntegerType() || isa<llvm::PointerType>(Src->getType())) && 530 "Unknown scalar type to convert"); 531 532 if (isa<llvm::IntegerType>(Src->getType())) 533 return EmitIntToBoolConversion(Src); 534 535 assert(isa<llvm::PointerType>(Src->getType())); 536 return EmitPointerToBoolConversion(Src); 537} 538 539/// EmitScalarConversion - Emit a conversion from the specified type to the 540/// specified destination type, both of which are LLVM scalar types. 541Value *ScalarExprEmitter::EmitScalarConversion(Value *Src, QualType SrcType, 542 QualType DstType) { 543 SrcType = CGF.getContext().getCanonicalType(SrcType); 544 DstType = CGF.getContext().getCanonicalType(DstType); 545 if (SrcType == DstType) return Src; 546 547 if (DstType->isVoidType()) return 0; 548 549 // Handle conversions to bool first, they are special: comparisons against 0. 550 if (DstType->isBooleanType()) 551 return EmitConversionToBool(Src, SrcType); 552 553 const llvm::Type *DstTy = ConvertType(DstType); 554 555 // Ignore conversions like int -> uint. 556 if (Src->getType() == DstTy) 557 return Src; 558 559 // Handle pointer conversions next: pointers can only be converted to/from 560 // other pointers and integers. Check for pointer types in terms of LLVM, as 561 // some native types (like Obj-C id) may map to a pointer type. 562 if (isa<llvm::PointerType>(DstTy)) { 563 // The source value may be an integer, or a pointer. 564 if (isa<llvm::PointerType>(Src->getType())) 565 return Builder.CreateBitCast(Src, DstTy, "conv"); 566 567 assert(SrcType->isIntegerType() && "Not ptr->ptr or int->ptr conversion?"); 568 // First, convert to the correct width so that we control the kind of 569 // extension. 570 const llvm::Type *MiddleTy = CGF.IntPtrTy; 571 bool InputSigned = SrcType->isSignedIntegerType(); 572 llvm::Value* IntResult = 573 Builder.CreateIntCast(Src, MiddleTy, InputSigned, "conv"); 574 // Then, cast to pointer. 575 return Builder.CreateIntToPtr(IntResult, DstTy, "conv"); 576 } 577 578 if (isa<llvm::PointerType>(Src->getType())) { 579 // Must be an ptr to int cast. 580 assert(isa<llvm::IntegerType>(DstTy) && "not ptr->int?"); 581 return Builder.CreatePtrToInt(Src, DstTy, "conv"); 582 } 583 584 // A scalar can be splatted to an extended vector of the same element type 585 if (DstType->isExtVectorType() && !SrcType->isVectorType()) { 586 // Cast the scalar to element type 587 QualType EltTy = DstType->getAs<ExtVectorType>()->getElementType(); 588 llvm::Value *Elt = EmitScalarConversion(Src, SrcType, EltTy); 589 590 // Insert the element in element zero of an undef vector 591 llvm::Value *UnV = llvm::UndefValue::get(DstTy); 592 llvm::Value *Idx = Builder.getInt32(0); 593 UnV = Builder.CreateInsertElement(UnV, Elt, Idx, "tmp"); 594 595 // Splat the element across to all elements 596 llvm::SmallVector<llvm::Constant*, 16> Args; 597 unsigned NumElements = cast<llvm::VectorType>(DstTy)->getNumElements(); 598 for (unsigned i = 0; i != NumElements; ++i) 599 Args.push_back(Builder.getInt32(0)); 600 601 llvm::Constant *Mask = llvm::ConstantVector::get(Args); 602 llvm::Value *Yay = Builder.CreateShuffleVector(UnV, UnV, Mask, "splat"); 603 return Yay; 604 } 605 606 // Allow bitcast from vector to integer/fp of the same size. 607 if (isa<llvm::VectorType>(Src->getType()) || 608 isa<llvm::VectorType>(DstTy)) 609 return Builder.CreateBitCast(Src, DstTy, "conv"); 610 611 // Finally, we have the arithmetic types: real int/float. 612 if (isa<llvm::IntegerType>(Src->getType())) { 613 bool InputSigned = SrcType->isSignedIntegerType(); 614 if (isa<llvm::IntegerType>(DstTy)) 615 return Builder.CreateIntCast(Src, DstTy, InputSigned, "conv"); 616 else if (InputSigned) 617 return Builder.CreateSIToFP(Src, DstTy, "conv"); 618 else 619 return Builder.CreateUIToFP(Src, DstTy, "conv"); 620 } 621 622 assert(Src->getType()->isFloatingPointTy() && "Unknown real conversion"); 623 if (isa<llvm::IntegerType>(DstTy)) { 624 if (DstType->isSignedIntegerType()) 625 return Builder.CreateFPToSI(Src, DstTy, "conv"); 626 else 627 return Builder.CreateFPToUI(Src, DstTy, "conv"); 628 } 629 630 assert(DstTy->isFloatingPointTy() && "Unknown real conversion"); 631 if (DstTy->getTypeID() < Src->getType()->getTypeID()) 632 return Builder.CreateFPTrunc(Src, DstTy, "conv"); 633 else 634 return Builder.CreateFPExt(Src, DstTy, "conv"); 635} 636 637/// EmitComplexToScalarConversion - Emit a conversion from the specified complex 638/// type to the specified destination type, where the destination type is an 639/// LLVM scalar type. 640Value *ScalarExprEmitter:: 641EmitComplexToScalarConversion(CodeGenFunction::ComplexPairTy Src, 642 QualType SrcTy, QualType DstTy) { 643 // Get the source element type. 644 SrcTy = SrcTy->getAs<ComplexType>()->getElementType(); 645 646 // Handle conversions to bool first, they are special: comparisons against 0. 647 if (DstTy->isBooleanType()) { 648 // Complex != 0 -> (Real != 0) | (Imag != 0) 649 Src.first = EmitScalarConversion(Src.first, SrcTy, DstTy); 650 Src.second = EmitScalarConversion(Src.second, SrcTy, DstTy); 651 return Builder.CreateOr(Src.first, Src.second, "tobool"); 652 } 653 654 // C99 6.3.1.7p2: "When a value of complex type is converted to a real type, 655 // the imaginary part of the complex value is discarded and the value of the 656 // real part is converted according to the conversion rules for the 657 // corresponding real type. 658 return EmitScalarConversion(Src.first, SrcTy, DstTy); 659} 660 661Value *ScalarExprEmitter::EmitNullValue(QualType Ty) { 662 if (const MemberPointerType *MPT = Ty->getAs<MemberPointerType>()) 663 return CGF.CGM.getCXXABI().EmitNullMemberPointer(MPT); 664 665 return llvm::Constant::getNullValue(ConvertType(Ty)); 666} 667 668//===----------------------------------------------------------------------===// 669// Visitor Methods 670//===----------------------------------------------------------------------===// 671 672Value *ScalarExprEmitter::VisitExpr(Expr *E) { 673 CGF.ErrorUnsupported(E, "scalar expression"); 674 if (E->getType()->isVoidType()) 675 return 0; 676 return llvm::UndefValue::get(CGF.ConvertType(E->getType())); 677} 678 679Value *ScalarExprEmitter::VisitShuffleVectorExpr(ShuffleVectorExpr *E) { 680 // Vector Mask Case 681 if (E->getNumSubExprs() == 2 || 682 (E->getNumSubExprs() == 3 && E->getExpr(2)->getType()->isVectorType())) { 683 Value *LHS = CGF.EmitScalarExpr(E->getExpr(0)); 684 Value *RHS = CGF.EmitScalarExpr(E->getExpr(1)); 685 Value *Mask; 686 687 const llvm::VectorType *LTy = cast<llvm::VectorType>(LHS->getType()); 688 unsigned LHSElts = LTy->getNumElements(); 689 690 if (E->getNumSubExprs() == 3) { 691 Mask = CGF.EmitScalarExpr(E->getExpr(2)); 692 693 // Shuffle LHS & RHS into one input vector. 694 llvm::SmallVector<llvm::Constant*, 32> concat; 695 for (unsigned i = 0; i != LHSElts; ++i) { 696 concat.push_back(Builder.getInt32(2*i)); 697 concat.push_back(Builder.getInt32(2*i+1)); 698 } 699 700 Value* CV = llvm::ConstantVector::get(concat); 701 LHS = Builder.CreateShuffleVector(LHS, RHS, CV, "concat"); 702 LHSElts *= 2; 703 } else { 704 Mask = RHS; 705 } 706 707 const llvm::VectorType *MTy = cast<llvm::VectorType>(Mask->getType()); 708 llvm::Constant* EltMask; 709 710 // Treat vec3 like vec4. 711 if ((LHSElts == 6) && (E->getNumSubExprs() == 3)) 712 EltMask = llvm::ConstantInt::get(MTy->getElementType(), 713 (1 << llvm::Log2_32(LHSElts+2))-1); 714 else if ((LHSElts == 3) && (E->getNumSubExprs() == 2)) 715 EltMask = llvm::ConstantInt::get(MTy->getElementType(), 716 (1 << llvm::Log2_32(LHSElts+1))-1); 717 else 718 EltMask = llvm::ConstantInt::get(MTy->getElementType(), 719 (1 << llvm::Log2_32(LHSElts))-1); 720 721 // Mask off the high bits of each shuffle index. 722 llvm::SmallVector<llvm::Constant *, 32> MaskV; 723 for (unsigned i = 0, e = MTy->getNumElements(); i != e; ++i) 724 MaskV.push_back(EltMask); 725 726 Value* MaskBits = llvm::ConstantVector::get(MaskV); 727 Mask = Builder.CreateAnd(Mask, MaskBits, "mask"); 728 729 // newv = undef 730 // mask = mask & maskbits 731 // for each elt 732 // n = extract mask i 733 // x = extract val n 734 // newv = insert newv, x, i 735 const llvm::VectorType *RTy = llvm::VectorType::get(LTy->getElementType(), 736 MTy->getNumElements()); 737 Value* NewV = llvm::UndefValue::get(RTy); 738 for (unsigned i = 0, e = MTy->getNumElements(); i != e; ++i) { 739 Value *Indx = Builder.getInt32(i); 740 Indx = Builder.CreateExtractElement(Mask, Indx, "shuf_idx"); 741 Indx = Builder.CreateZExt(Indx, CGF.Int32Ty, "idx_zext"); 742 743 // Handle vec3 special since the index will be off by one for the RHS. 744 if ((LHSElts == 6) && (E->getNumSubExprs() == 3)) { 745 Value *cmpIndx, *newIndx; 746 cmpIndx = Builder.CreateICmpUGT(Indx, Builder.getInt32(3), 747 "cmp_shuf_idx"); 748 newIndx = Builder.CreateSub(Indx, Builder.getInt32(1), "shuf_idx_adj"); 749 Indx = Builder.CreateSelect(cmpIndx, newIndx, Indx, "sel_shuf_idx"); 750 } 751 Value *VExt = Builder.CreateExtractElement(LHS, Indx, "shuf_elt"); 752 NewV = Builder.CreateInsertElement(NewV, VExt, Indx, "shuf_ins"); 753 } 754 return NewV; 755 } 756 757 Value* V1 = CGF.EmitScalarExpr(E->getExpr(0)); 758 Value* V2 = CGF.EmitScalarExpr(E->getExpr(1)); 759 760 // Handle vec3 special since the index will be off by one for the RHS. 761 llvm::SmallVector<llvm::Constant*, 32> indices; 762 for (unsigned i = 2; i < E->getNumSubExprs(); i++) { 763 llvm::Constant *C = cast<llvm::Constant>(CGF.EmitScalarExpr(E->getExpr(i))); 764 const llvm::VectorType *VTy = cast<llvm::VectorType>(V1->getType()); 765 if (VTy->getNumElements() == 3) { 766 if (llvm::ConstantInt *CI = dyn_cast<llvm::ConstantInt>(C)) { 767 uint64_t cVal = CI->getZExtValue(); 768 if (cVal > 3) { 769 C = llvm::ConstantInt::get(C->getType(), cVal-1); 770 } 771 } 772 } 773 indices.push_back(C); 774 } 775 776 Value *SV = llvm::ConstantVector::get(indices); 777 return Builder.CreateShuffleVector(V1, V2, SV, "shuffle"); 778} 779Value *ScalarExprEmitter::VisitMemberExpr(MemberExpr *E) { 780 Expr::EvalResult Result; 781 if (E->Evaluate(Result, CGF.getContext()) && Result.Val.isInt()) { 782 if (E->isArrow()) 783 CGF.EmitScalarExpr(E->getBase()); 784 else 785 EmitLValue(E->getBase()); 786 return Builder.getInt(Result.Val.getInt()); 787 } 788 789 // Emit debug info for aggregate now, if it was delayed to reduce 790 // debug info size. 791 CGDebugInfo *DI = CGF.getDebugInfo(); 792 if (DI && CGF.CGM.getCodeGenOpts().LimitDebugInfo) { 793 QualType PQTy = E->getBase()->IgnoreParenImpCasts()->getType(); 794 if (const PointerType * PTy = dyn_cast<PointerType>(PQTy)) 795 if (FieldDecl *M = dyn_cast<FieldDecl>(E->getMemberDecl())) 796 DI->getOrCreateRecordType(PTy->getPointeeType(), 797 M->getParent()->getLocation()); 798 } 799 return EmitLoadOfLValue(E); 800} 801 802Value *ScalarExprEmitter::VisitArraySubscriptExpr(ArraySubscriptExpr *E) { 803 TestAndClearIgnoreResultAssign(); 804 805 // Emit subscript expressions in rvalue context's. For most cases, this just 806 // loads the lvalue formed by the subscript expr. However, we have to be 807 // careful, because the base of a vector subscript is occasionally an rvalue, 808 // so we can't get it as an lvalue. 809 if (!E->getBase()->getType()->isVectorType()) 810 return EmitLoadOfLValue(E); 811 812 // Handle the vector case. The base must be a vector, the index must be an 813 // integer value. 814 Value *Base = Visit(E->getBase()); 815 Value *Idx = Visit(E->getIdx()); 816 bool IdxSigned = E->getIdx()->getType()->isSignedIntegerType(); 817 Idx = Builder.CreateIntCast(Idx, CGF.Int32Ty, IdxSigned, "vecidxcast"); 818 return Builder.CreateExtractElement(Base, Idx, "vecext"); 819} 820 821static llvm::Constant *getMaskElt(llvm::ShuffleVectorInst *SVI, unsigned Idx, 822 unsigned Off, const llvm::Type *I32Ty) { 823 int MV = SVI->getMaskValue(Idx); 824 if (MV == -1) 825 return llvm::UndefValue::get(I32Ty); 826 return llvm::ConstantInt::get(I32Ty, Off+MV); 827} 828 829Value *ScalarExprEmitter::VisitInitListExpr(InitListExpr *E) { 830 bool Ignore = TestAndClearIgnoreResultAssign(); 831 (void)Ignore; 832 assert (Ignore == false && "init list ignored"); 833 unsigned NumInitElements = E->getNumInits(); 834 835 if (E->hadArrayRangeDesignator()) 836 CGF.ErrorUnsupported(E, "GNU array range designator extension"); 837 838 const llvm::VectorType *VType = 839 dyn_cast<llvm::VectorType>(ConvertType(E->getType())); 840 841 // We have a scalar in braces. Just use the first element. 842 if (!VType) 843 return Visit(E->getInit(0)); 844 845 unsigned ResElts = VType->getNumElements(); 846 847 // Loop over initializers collecting the Value for each, and remembering 848 // whether the source was swizzle (ExtVectorElementExpr). This will allow 849 // us to fold the shuffle for the swizzle into the shuffle for the vector 850 // initializer, since LLVM optimizers generally do not want to touch 851 // shuffles. 852 unsigned CurIdx = 0; 853 bool VIsUndefShuffle = false; 854 llvm::Value *V = llvm::UndefValue::get(VType); 855 for (unsigned i = 0; i != NumInitElements; ++i) { 856 Expr *IE = E->getInit(i); 857 Value *Init = Visit(IE); 858 llvm::SmallVector<llvm::Constant*, 16> Args; 859 860 const llvm::VectorType *VVT = dyn_cast<llvm::VectorType>(Init->getType()); 861 862 // Handle scalar elements. If the scalar initializer is actually one 863 // element of a different vector of the same width, use shuffle instead of 864 // extract+insert. 865 if (!VVT) { 866 if (isa<ExtVectorElementExpr>(IE)) { 867 llvm::ExtractElementInst *EI = cast<llvm::ExtractElementInst>(Init); 868 869 if (EI->getVectorOperandType()->getNumElements() == ResElts) { 870 llvm::ConstantInt *C = cast<llvm::ConstantInt>(EI->getIndexOperand()); 871 Value *LHS = 0, *RHS = 0; 872 if (CurIdx == 0) { 873 // insert into undef -> shuffle (src, undef) 874 Args.push_back(C); 875 for (unsigned j = 1; j != ResElts; ++j) 876 Args.push_back(llvm::UndefValue::get(CGF.Int32Ty)); 877 878 LHS = EI->getVectorOperand(); 879 RHS = V; 880 VIsUndefShuffle = true; 881 } else if (VIsUndefShuffle) { 882 // insert into undefshuffle && size match -> shuffle (v, src) 883 llvm::ShuffleVectorInst *SVV = cast<llvm::ShuffleVectorInst>(V); 884 for (unsigned j = 0; j != CurIdx; ++j) 885 Args.push_back(getMaskElt(SVV, j, 0, CGF.Int32Ty)); 886 Args.push_back(Builder.getInt32(ResElts + C->getZExtValue())); 887 for (unsigned j = CurIdx + 1; j != ResElts; ++j) 888 Args.push_back(llvm::UndefValue::get(CGF.Int32Ty)); 889 890 LHS = cast<llvm::ShuffleVectorInst>(V)->getOperand(0); 891 RHS = EI->getVectorOperand(); 892 VIsUndefShuffle = false; 893 } 894 if (!Args.empty()) { 895 llvm::Constant *Mask = llvm::ConstantVector::get(Args); 896 V = Builder.CreateShuffleVector(LHS, RHS, Mask); 897 ++CurIdx; 898 continue; 899 } 900 } 901 } 902 V = Builder.CreateInsertElement(V, Init, Builder.getInt32(CurIdx), 903 "vecinit"); 904 VIsUndefShuffle = false; 905 ++CurIdx; 906 continue; 907 } 908 909 unsigned InitElts = VVT->getNumElements(); 910 911 // If the initializer is an ExtVecEltExpr (a swizzle), and the swizzle's 912 // input is the same width as the vector being constructed, generate an 913 // optimized shuffle of the swizzle input into the result. 914 unsigned Offset = (CurIdx == 0) ? 0 : ResElts; 915 if (isa<ExtVectorElementExpr>(IE)) { 916 llvm::ShuffleVectorInst *SVI = cast<llvm::ShuffleVectorInst>(Init); 917 Value *SVOp = SVI->getOperand(0); 918 const llvm::VectorType *OpTy = cast<llvm::VectorType>(SVOp->getType()); 919 920 if (OpTy->getNumElements() == ResElts) { 921 for (unsigned j = 0; j != CurIdx; ++j) { 922 // If the current vector initializer is a shuffle with undef, merge 923 // this shuffle directly into it. 924 if (VIsUndefShuffle) { 925 Args.push_back(getMaskElt(cast<llvm::ShuffleVectorInst>(V), j, 0, 926 CGF.Int32Ty)); 927 } else { 928 Args.push_back(Builder.getInt32(j)); 929 } 930 } 931 for (unsigned j = 0, je = InitElts; j != je; ++j) 932 Args.push_back(getMaskElt(SVI, j, Offset, CGF.Int32Ty)); 933 for (unsigned j = CurIdx + InitElts; j != ResElts; ++j) 934 Args.push_back(llvm::UndefValue::get(CGF.Int32Ty)); 935 936 if (VIsUndefShuffle) 937 V = cast<llvm::ShuffleVectorInst>(V)->getOperand(0); 938 939 Init = SVOp; 940 } 941 } 942 943 // Extend init to result vector length, and then shuffle its contribution 944 // to the vector initializer into V. 945 if (Args.empty()) { 946 for (unsigned j = 0; j != InitElts; ++j) 947 Args.push_back(Builder.getInt32(j)); 948 for (unsigned j = InitElts; j != ResElts; ++j) 949 Args.push_back(llvm::UndefValue::get(CGF.Int32Ty)); 950 llvm::Constant *Mask = llvm::ConstantVector::get(Args); 951 Init = Builder.CreateShuffleVector(Init, llvm::UndefValue::get(VVT), 952 Mask, "vext"); 953 954 Args.clear(); 955 for (unsigned j = 0; j != CurIdx; ++j) 956 Args.push_back(Builder.getInt32(j)); 957 for (unsigned j = 0; j != InitElts; ++j) 958 Args.push_back(Builder.getInt32(j+Offset)); 959 for (unsigned j = CurIdx + InitElts; j != ResElts; ++j) 960 Args.push_back(llvm::UndefValue::get(CGF.Int32Ty)); 961 } 962 963 // If V is undef, make sure it ends up on the RHS of the shuffle to aid 964 // merging subsequent shuffles into this one. 965 if (CurIdx == 0) 966 std::swap(V, Init); 967 llvm::Constant *Mask = llvm::ConstantVector::get(Args); 968 V = Builder.CreateShuffleVector(V, Init, Mask, "vecinit"); 969 VIsUndefShuffle = isa<llvm::UndefValue>(Init); 970 CurIdx += InitElts; 971 } 972 973 // FIXME: evaluate codegen vs. shuffling against constant null vector. 974 // Emit remaining default initializers. 975 const llvm::Type *EltTy = VType->getElementType(); 976 977 // Emit remaining default initializers 978 for (/* Do not initialize i*/; CurIdx < ResElts; ++CurIdx) { 979 Value *Idx = Builder.getInt32(CurIdx); 980 llvm::Value *Init = llvm::Constant::getNullValue(EltTy); 981 V = Builder.CreateInsertElement(V, Init, Idx, "vecinit"); 982 } 983 return V; 984} 985 986static bool ShouldNullCheckClassCastValue(const CastExpr *CE) { 987 const Expr *E = CE->getSubExpr(); 988 989 if (CE->getCastKind() == CK_UncheckedDerivedToBase) 990 return false; 991 992 if (isa<CXXThisExpr>(E)) { 993 // We always assume that 'this' is never null. 994 return false; 995 } 996 997 if (const ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(CE)) { 998 // And that glvalue casts are never null. 999 if (ICE->getValueKind() != VK_RValue) 1000 return false; 1001 } 1002 1003 return true; 1004} 1005 1006// VisitCastExpr - Emit code for an explicit or implicit cast. Implicit casts 1007// have to handle a more broad range of conversions than explicit casts, as they 1008// handle things like function to ptr-to-function decay etc. 1009Value *ScalarExprEmitter::EmitCastExpr(CastExpr *CE) { 1010 Expr *E = CE->getSubExpr(); 1011 QualType DestTy = CE->getType(); 1012 CastKind Kind = CE->getCastKind(); 1013 1014 if (!DestTy->isVoidType()) 1015 TestAndClearIgnoreResultAssign(); 1016 1017 // Since almost all cast kinds apply to scalars, this switch doesn't have 1018 // a default case, so the compiler will warn on a missing case. The cases 1019 // are in the same order as in the CastKind enum. 1020 switch (Kind) { 1021 case CK_Dependent: llvm_unreachable("dependent cast kind in IR gen!"); 1022 1023 case CK_LValueBitCast: 1024 case CK_ObjCObjectLValueCast: { 1025 Value *V = EmitLValue(E).getAddress(); 1026 V = Builder.CreateBitCast(V, 1027 ConvertType(CGF.getContext().getPointerType(DestTy))); 1028 return EmitLoadOfLValue(CGF.MakeAddrLValue(V, DestTy), DestTy); 1029 } 1030 1031 case CK_AnyPointerToObjCPointerCast: 1032 case CK_AnyPointerToBlockPointerCast: 1033 case CK_BitCast: { 1034 Value *Src = Visit(const_cast<Expr*>(E)); 1035 return Builder.CreateBitCast(Src, ConvertType(DestTy)); 1036 } 1037 case CK_NoOp: 1038 case CK_UserDefinedConversion: 1039 return Visit(const_cast<Expr*>(E)); 1040 1041 case CK_BaseToDerived: { 1042 const CXXRecordDecl *DerivedClassDecl = 1043 DestTy->getCXXRecordDeclForPointerType(); 1044 1045 return CGF.GetAddressOfDerivedClass(Visit(E), DerivedClassDecl, 1046 CE->path_begin(), CE->path_end(), 1047 ShouldNullCheckClassCastValue(CE)); 1048 } 1049 case CK_UncheckedDerivedToBase: 1050 case CK_DerivedToBase: { 1051 const RecordType *DerivedClassTy = 1052 E->getType()->getAs<PointerType>()->getPointeeType()->getAs<RecordType>(); 1053 CXXRecordDecl *DerivedClassDecl = 1054 cast<CXXRecordDecl>(DerivedClassTy->getDecl()); 1055 1056 return CGF.GetAddressOfBaseClass(Visit(E), DerivedClassDecl, 1057 CE->path_begin(), CE->path_end(), 1058 ShouldNullCheckClassCastValue(CE)); 1059 } 1060 case CK_Dynamic: { 1061 Value *V = Visit(const_cast<Expr*>(E)); 1062 const CXXDynamicCastExpr *DCE = cast<CXXDynamicCastExpr>(CE); 1063 return CGF.EmitDynamicCast(V, DCE); 1064 } 1065 1066 case CK_ArrayToPointerDecay: { 1067 assert(E->getType()->isArrayType() && 1068 "Array to pointer decay must have array source type!"); 1069 1070 Value *V = EmitLValue(E).getAddress(); // Bitfields can't be arrays. 1071 1072 // Note that VLA pointers are always decayed, so we don't need to do 1073 // anything here. 1074 if (!E->getType()->isVariableArrayType()) { 1075 assert(isa<llvm::PointerType>(V->getType()) && "Expected pointer"); 1076 assert(isa<llvm::ArrayType>(cast<llvm::PointerType>(V->getType()) 1077 ->getElementType()) && 1078 "Expected pointer to array"); 1079 V = Builder.CreateStructGEP(V, 0, "arraydecay"); 1080 } 1081 1082 return V; 1083 } 1084 case CK_FunctionToPointerDecay: 1085 return EmitLValue(E).getAddress(); 1086 1087 case CK_NullToPointer: 1088 if (MustVisitNullValue(E)) 1089 (void) Visit(E); 1090 1091 return llvm::ConstantPointerNull::get( 1092 cast<llvm::PointerType>(ConvertType(DestTy))); 1093 1094 case CK_NullToMemberPointer: { 1095 if (MustVisitNullValue(E)) 1096 (void) Visit(E); 1097 1098 const MemberPointerType *MPT = CE->getType()->getAs<MemberPointerType>(); 1099 return CGF.CGM.getCXXABI().EmitNullMemberPointer(MPT); 1100 } 1101 1102 case CK_BaseToDerivedMemberPointer: 1103 case CK_DerivedToBaseMemberPointer: { 1104 Value *Src = Visit(E); 1105 1106 // Note that the AST doesn't distinguish between checked and 1107 // unchecked member pointer conversions, so we always have to 1108 // implement checked conversions here. This is inefficient when 1109 // actual control flow may be required in order to perform the 1110 // check, which it is for data member pointers (but not member 1111 // function pointers on Itanium and ARM). 1112 return CGF.CGM.getCXXABI().EmitMemberPointerConversion(CGF, CE, Src); 1113 } 1114 1115 case CK_FloatingRealToComplex: 1116 case CK_FloatingComplexCast: 1117 case CK_IntegralRealToComplex: 1118 case CK_IntegralComplexCast: 1119 case CK_IntegralComplexToFloatingComplex: 1120 case CK_FloatingComplexToIntegralComplex: 1121 case CK_ConstructorConversion: 1122 case CK_ToUnion: 1123 llvm_unreachable("scalar cast to non-scalar value"); 1124 break; 1125 1126 case CK_GetObjCProperty: { 1127 assert(CGF.getContext().hasSameUnqualifiedType(E->getType(), DestTy)); 1128 assert(E->isGLValue() && E->getObjectKind() == OK_ObjCProperty && 1129 "CK_GetObjCProperty for non-lvalue or non-ObjCProperty"); 1130 RValue RV = CGF.EmitLoadOfLValue(CGF.EmitLValue(E), E->getType()); 1131 return RV.getScalarVal(); 1132 } 1133 1134 case CK_LValueToRValue: 1135 assert(CGF.getContext().hasSameUnqualifiedType(E->getType(), DestTy)); 1136 assert(E->isGLValue() && "lvalue-to-rvalue applied to r-value!"); 1137 return Visit(const_cast<Expr*>(E)); 1138 1139 case CK_IntegralToPointer: { 1140 Value *Src = Visit(const_cast<Expr*>(E)); 1141 1142 // First, convert to the correct width so that we control the kind of 1143 // extension. 1144 const llvm::Type *MiddleTy = CGF.IntPtrTy; 1145 bool InputSigned = E->getType()->isSignedIntegerType(); 1146 llvm::Value* IntResult = 1147 Builder.CreateIntCast(Src, MiddleTy, InputSigned, "conv"); 1148 1149 return Builder.CreateIntToPtr(IntResult, ConvertType(DestTy)); 1150 } 1151 case CK_PointerToIntegral: { 1152 Value *Src = Visit(const_cast<Expr*>(E)); 1153 1154 // Handle conversion to bool correctly. 1155 if (DestTy->isBooleanType()) 1156 return EmitScalarConversion(Src, E->getType(), DestTy); 1157 1158 return Builder.CreatePtrToInt(Src, ConvertType(DestTy)); 1159 } 1160 case CK_ToVoid: { 1161 CGF.EmitIgnoredExpr(E); 1162 return 0; 1163 } 1164 case CK_VectorSplat: { 1165 const llvm::Type *DstTy = ConvertType(DestTy); 1166 Value *Elt = Visit(const_cast<Expr*>(E)); 1167 1168 // Insert the element in element zero of an undef vector 1169 llvm::Value *UnV = llvm::UndefValue::get(DstTy); 1170 llvm::Value *Idx = Builder.getInt32(0); 1171 UnV = Builder.CreateInsertElement(UnV, Elt, Idx, "tmp"); 1172 1173 // Splat the element across to all elements 1174 llvm::SmallVector<llvm::Constant*, 16> Args; 1175 unsigned NumElements = cast<llvm::VectorType>(DstTy)->getNumElements(); 1176 llvm::Constant *Zero = Builder.getInt32(0); 1177 for (unsigned i = 0; i < NumElements; i++) 1178 Args.push_back(Zero); 1179 1180 llvm::Constant *Mask = llvm::ConstantVector::get(Args); 1181 llvm::Value *Yay = Builder.CreateShuffleVector(UnV, UnV, Mask, "splat"); 1182 return Yay; 1183 } 1184 1185 case CK_IntegralCast: 1186 case CK_IntegralToFloating: 1187 case CK_FloatingToIntegral: 1188 case CK_FloatingCast: 1189 return EmitScalarConversion(Visit(E), E->getType(), DestTy); 1190 1191 case CK_IntegralToBoolean: 1192 return EmitIntToBoolConversion(Visit(E)); 1193 case CK_PointerToBoolean: 1194 return EmitPointerToBoolConversion(Visit(E)); 1195 case CK_FloatingToBoolean: 1196 return EmitFloatToBoolConversion(Visit(E)); 1197 case CK_MemberPointerToBoolean: { 1198 llvm::Value *MemPtr = Visit(E); 1199 const MemberPointerType *MPT = E->getType()->getAs<MemberPointerType>(); 1200 return CGF.CGM.getCXXABI().EmitMemberPointerIsNotNull(CGF, MemPtr, MPT); 1201 } 1202 1203 case CK_FloatingComplexToReal: 1204 case CK_IntegralComplexToReal: 1205 return CGF.EmitComplexExpr(E, false, true).first; 1206 1207 case CK_FloatingComplexToBoolean: 1208 case CK_IntegralComplexToBoolean: { 1209 CodeGenFunction::ComplexPairTy V = CGF.EmitComplexExpr(E); 1210 1211 // TODO: kill this function off, inline appropriate case here 1212 return EmitComplexToScalarConversion(V, E->getType(), DestTy); 1213 } 1214 1215 } 1216 1217 llvm_unreachable("unknown scalar cast"); 1218 return 0; 1219} 1220 1221Value *ScalarExprEmitter::VisitStmtExpr(const StmtExpr *E) { 1222 CodeGenFunction::StmtExprEvaluation eval(CGF); 1223 return CGF.EmitCompoundStmt(*E->getSubStmt(), !E->getType()->isVoidType()) 1224 .getScalarVal(); 1225} 1226 1227Value *ScalarExprEmitter::VisitBlockDeclRefExpr(const BlockDeclRefExpr *E) { 1228 LValue LV = CGF.EmitBlockDeclRefLValue(E); 1229 return CGF.EmitLoadOfLValue(LV, E->getType()).getScalarVal(); 1230} 1231 1232//===----------------------------------------------------------------------===// 1233// Unary Operators 1234//===----------------------------------------------------------------------===// 1235 1236llvm::Value *ScalarExprEmitter:: 1237EmitAddConsiderOverflowBehavior(const UnaryOperator *E, 1238 llvm::Value *InVal, 1239 llvm::Value *NextVal, bool IsInc) { 1240 switch (CGF.getContext().getLangOptions().getSignedOverflowBehavior()) { 1241 case LangOptions::SOB_Undefined: 1242 return Builder.CreateNSWAdd(InVal, NextVal, IsInc ? "inc" : "dec"); 1243 break; 1244 case LangOptions::SOB_Defined: 1245 return Builder.CreateAdd(InVal, NextVal, IsInc ? "inc" : "dec"); 1246 break; 1247 case LangOptions::SOB_Trapping: 1248 BinOpInfo BinOp; 1249 BinOp.LHS = InVal; 1250 BinOp.RHS = NextVal; 1251 BinOp.Ty = E->getType(); 1252 BinOp.Opcode = BO_Add; 1253 BinOp.E = E; 1254 return EmitOverflowCheckedBinOp(BinOp); 1255 break; 1256 } 1257 assert(false && "Unknown SignedOverflowBehaviorTy"); 1258 return 0; 1259} 1260 1261llvm::Value * 1262ScalarExprEmitter::EmitScalarPrePostIncDec(const UnaryOperator *E, LValue LV, 1263 bool isInc, bool isPre) { 1264 1265 QualType type = E->getSubExpr()->getType(); 1266 llvm::Value *value = EmitLoadOfLValue(LV, type); 1267 llvm::Value *input = value; 1268 1269 int amount = (isInc ? 1 : -1); 1270 1271 // Special case of integer increment that we have to check first: bool++. 1272 // Due to promotion rules, we get: 1273 // bool++ -> bool = bool + 1 1274 // -> bool = (int)bool + 1 1275 // -> bool = ((int)bool + 1 != 0) 1276 // An interesting aspect of this is that increment is always true. 1277 // Decrement does not have this property. 1278 if (isInc && type->isBooleanType()) { 1279 value = Builder.getTrue(); 1280 1281 // Most common case by far: integer increment. 1282 } else if (type->isIntegerType()) { 1283 1284 llvm::Value *amt = llvm::ConstantInt::get(value->getType(), amount); 1285 1286 // Note that signed integer inc/dec with width less than int can't 1287 // overflow because of promotion rules; we're just eliding a few steps here. 1288 if (type->isSignedIntegerType() && 1289 value->getType()->getPrimitiveSizeInBits() >= 1290 CGF.CGM.IntTy->getBitWidth()) 1291 value = EmitAddConsiderOverflowBehavior(E, value, amt, isInc); 1292 else 1293 value = Builder.CreateAdd(value, amt, isInc ? "inc" : "dec"); 1294 1295 // Next most common: pointer increment. 1296 } else if (const PointerType *ptr = type->getAs<PointerType>()) { 1297 QualType type = ptr->getPointeeType(); 1298 1299 // VLA types don't have constant size. 1300 if (type->isVariableArrayType()) { 1301 llvm::Value *vlaSize = 1302 CGF.GetVLASize(CGF.getContext().getAsVariableArrayType(type)); 1303 value = CGF.EmitCastToVoidPtr(value); 1304 if (!isInc) vlaSize = Builder.CreateNSWNeg(vlaSize, "vla.negsize"); 1305 if (CGF.getContext().getLangOptions().isSignedOverflowDefined()) 1306 value = Builder.CreateGEP(value, vlaSize, "vla.inc"); 1307 else 1308 value = Builder.CreateInBoundsGEP(value, vlaSize, "vla.inc"); 1309 value = Builder.CreateBitCast(value, input->getType()); 1310 1311 // Arithmetic on function pointers (!) is just +-1. 1312 } else if (type->isFunctionType()) { 1313 llvm::Value *amt = Builder.getInt32(amount); 1314 1315 value = CGF.EmitCastToVoidPtr(value); 1316 if (CGF.getContext().getLangOptions().isSignedOverflowDefined()) 1317 value = Builder.CreateGEP(value, amt, "incdec.funcptr"); 1318 else 1319 value = Builder.CreateInBoundsGEP(value, amt, "incdec.funcptr"); 1320 value = Builder.CreateBitCast(value, input->getType()); 1321 1322 // For everything else, we can just do a simple increment. 1323 } else { 1324 llvm::Value *amt = Builder.getInt32(amount); 1325 if (CGF.getContext().getLangOptions().isSignedOverflowDefined()) 1326 value = Builder.CreateGEP(value, amt, "incdec.ptr"); 1327 else 1328 value = Builder.CreateInBoundsGEP(value, amt, "incdec.ptr"); 1329 } 1330 1331 // Vector increment/decrement. 1332 } else if (type->isVectorType()) { 1333 if (type->hasIntegerRepresentation()) { 1334 llvm::Value *amt = llvm::ConstantInt::get(value->getType(), amount); 1335 1336 value = Builder.CreateAdd(value, amt, isInc ? "inc" : "dec"); 1337 } else { 1338 value = Builder.CreateFAdd( 1339 value, 1340 llvm::ConstantFP::get(value->getType(), amount), 1341 isInc ? "inc" : "dec"); 1342 } 1343 1344 // Floating point. 1345 } else if (type->isRealFloatingType()) { 1346 // Add the inc/dec to the real part. 1347 llvm::Value *amt; 1348 if (value->getType()->isFloatTy()) 1349 amt = llvm::ConstantFP::get(VMContext, 1350 llvm::APFloat(static_cast<float>(amount))); 1351 else if (value->getType()->isDoubleTy()) 1352 amt = llvm::ConstantFP::get(VMContext, 1353 llvm::APFloat(static_cast<double>(amount))); 1354 else { 1355 llvm::APFloat F(static_cast<float>(amount)); 1356 bool ignored; 1357 F.convert(CGF.Target.getLongDoubleFormat(), llvm::APFloat::rmTowardZero, 1358 &ignored); 1359 amt = llvm::ConstantFP::get(VMContext, F); 1360 } 1361 value = Builder.CreateFAdd(value, amt, isInc ? "inc" : "dec"); 1362 1363 // Objective-C pointer types. 1364 } else { 1365 const ObjCObjectPointerType *OPT = type->castAs<ObjCObjectPointerType>(); 1366 value = CGF.EmitCastToVoidPtr(value); 1367 1368 CharUnits size = CGF.getContext().getTypeSizeInChars(OPT->getObjectType()); 1369 if (!isInc) size = -size; 1370 llvm::Value *sizeValue = 1371 llvm::ConstantInt::get(CGF.SizeTy, size.getQuantity()); 1372 1373 if (CGF.getContext().getLangOptions().isSignedOverflowDefined()) 1374 value = Builder.CreateGEP(value, sizeValue, "incdec.objptr"); 1375 else 1376 value = Builder.CreateInBoundsGEP(value, sizeValue, "incdec.objptr"); 1377 value = Builder.CreateBitCast(value, input->getType()); 1378 } 1379 1380 // Store the updated result through the lvalue. 1381 if (LV.isBitField()) 1382 CGF.EmitStoreThroughBitfieldLValue(RValue::get(value), LV, type, &value); 1383 else 1384 CGF.EmitStoreThroughLValue(RValue::get(value), LV, type); 1385 1386 // If this is a postinc, return the value read from memory, otherwise use the 1387 // updated value. 1388 return isPre ? value : input; 1389} 1390 1391 1392 1393Value *ScalarExprEmitter::VisitUnaryMinus(const UnaryOperator *E) { 1394 TestAndClearIgnoreResultAssign(); 1395 // Emit unary minus with EmitSub so we handle overflow cases etc. 1396 BinOpInfo BinOp; 1397 BinOp.RHS = Visit(E->getSubExpr()); 1398 1399 if (BinOp.RHS->getType()->isFPOrFPVectorTy()) 1400 BinOp.LHS = llvm::ConstantFP::getZeroValueForNegation(BinOp.RHS->getType()); 1401 else 1402 BinOp.LHS = llvm::Constant::getNullValue(BinOp.RHS->getType()); 1403 BinOp.Ty = E->getType(); 1404 BinOp.Opcode = BO_Sub; 1405 BinOp.E = E; 1406 return EmitSub(BinOp); 1407} 1408 1409Value *ScalarExprEmitter::VisitUnaryNot(const UnaryOperator *E) { 1410 TestAndClearIgnoreResultAssign(); 1411 Value *Op = Visit(E->getSubExpr()); 1412 return Builder.CreateNot(Op, "neg"); 1413} 1414 1415Value *ScalarExprEmitter::VisitUnaryLNot(const UnaryOperator *E) { 1416 // Compare operand to zero. 1417 Value *BoolVal = CGF.EvaluateExprAsBool(E->getSubExpr()); 1418 1419 // Invert value. 1420 // TODO: Could dynamically modify easy computations here. For example, if 1421 // the operand is an icmp ne, turn into icmp eq. 1422 BoolVal = Builder.CreateNot(BoolVal, "lnot"); 1423 1424 // ZExt result to the expr type. 1425 return Builder.CreateZExt(BoolVal, ConvertType(E->getType()), "lnot.ext"); 1426} 1427 1428Value *ScalarExprEmitter::VisitOffsetOfExpr(OffsetOfExpr *E) { 1429 // Try folding the offsetof to a constant. 1430 Expr::EvalResult EvalResult; 1431 if (E->Evaluate(EvalResult, CGF.getContext())) 1432 return Builder.getInt(EvalResult.Val.getInt()); 1433 1434 // Loop over the components of the offsetof to compute the value. 1435 unsigned n = E->getNumComponents(); 1436 const llvm::Type* ResultType = ConvertType(E->getType()); 1437 llvm::Value* Result = llvm::Constant::getNullValue(ResultType); 1438 QualType CurrentType = E->getTypeSourceInfo()->getType(); 1439 for (unsigned i = 0; i != n; ++i) { 1440 OffsetOfExpr::OffsetOfNode ON = E->getComponent(i); 1441 llvm::Value *Offset = 0; 1442 switch (ON.getKind()) { 1443 case OffsetOfExpr::OffsetOfNode::Array: { 1444 // Compute the index 1445 Expr *IdxExpr = E->getIndexExpr(ON.getArrayExprIndex()); 1446 llvm::Value* Idx = CGF.EmitScalarExpr(IdxExpr); 1447 bool IdxSigned = IdxExpr->getType()->isSignedIntegerType(); 1448 Idx = Builder.CreateIntCast(Idx, ResultType, IdxSigned, "conv"); 1449 1450 // Save the element type 1451 CurrentType = 1452 CGF.getContext().getAsArrayType(CurrentType)->getElementType(); 1453 1454 // Compute the element size 1455 llvm::Value* ElemSize = llvm::ConstantInt::get(ResultType, 1456 CGF.getContext().getTypeSizeInChars(CurrentType).getQuantity()); 1457 1458 // Multiply out to compute the result 1459 Offset = Builder.CreateMul(Idx, ElemSize); 1460 break; 1461 } 1462 1463 case OffsetOfExpr::OffsetOfNode::Field: { 1464 FieldDecl *MemberDecl = ON.getField(); 1465 RecordDecl *RD = CurrentType->getAs<RecordType>()->getDecl(); 1466 const ASTRecordLayout &RL = CGF.getContext().getASTRecordLayout(RD); 1467 1468 // Compute the index of the field in its parent. 1469 unsigned i = 0; 1470 // FIXME: It would be nice if we didn't have to loop here! 1471 for (RecordDecl::field_iterator Field = RD->field_begin(), 1472 FieldEnd = RD->field_end(); 1473 Field != FieldEnd; (void)++Field, ++i) { 1474 if (*Field == MemberDecl) 1475 break; 1476 } 1477 assert(i < RL.getFieldCount() && "offsetof field in wrong type"); 1478 1479 // Compute the offset to the field 1480 int64_t OffsetInt = RL.getFieldOffset(i) / 1481 CGF.getContext().getCharWidth(); 1482 Offset = llvm::ConstantInt::get(ResultType, OffsetInt); 1483 1484 // Save the element type. 1485 CurrentType = MemberDecl->getType(); 1486 break; 1487 } 1488 1489 case OffsetOfExpr::OffsetOfNode::Identifier: 1490 llvm_unreachable("dependent __builtin_offsetof"); 1491 1492 case OffsetOfExpr::OffsetOfNode::Base: { 1493 if (ON.getBase()->isVirtual()) { 1494 CGF.ErrorUnsupported(E, "virtual base in offsetof"); 1495 continue; 1496 } 1497 1498 RecordDecl *RD = CurrentType->getAs<RecordType>()->getDecl(); 1499 const ASTRecordLayout &RL = CGF.getContext().getASTRecordLayout(RD); 1500 1501 // Save the element type. 1502 CurrentType = ON.getBase()->getType(); 1503 1504 // Compute the offset to the base. 1505 const RecordType *BaseRT = CurrentType->getAs<RecordType>(); 1506 CXXRecordDecl *BaseRD = cast<CXXRecordDecl>(BaseRT->getDecl()); 1507 int64_t OffsetInt = RL.getBaseClassOffsetInBits(BaseRD) / 1508 CGF.getContext().getCharWidth(); 1509 Offset = llvm::ConstantInt::get(ResultType, OffsetInt); 1510 break; 1511 } 1512 } 1513 Result = Builder.CreateAdd(Result, Offset); 1514 } 1515 return Result; 1516} 1517 1518/// VisitUnaryExprOrTypeTraitExpr - Return the size or alignment of the type of 1519/// argument of the sizeof expression as an integer. 1520Value * 1521ScalarExprEmitter::VisitUnaryExprOrTypeTraitExpr( 1522 const UnaryExprOrTypeTraitExpr *E) { 1523 QualType TypeToSize = E->getTypeOfArgument(); 1524 if (E->getKind() == UETT_SizeOf) { 1525 if (const VariableArrayType *VAT = 1526 CGF.getContext().getAsVariableArrayType(TypeToSize)) { 1527 if (E->isArgumentType()) { 1528 // sizeof(type) - make sure to emit the VLA size. 1529 CGF.EmitVLASize(TypeToSize); 1530 } else { 1531 // C99 6.5.3.4p2: If the argument is an expression of type 1532 // VLA, it is evaluated. 1533 CGF.EmitIgnoredExpr(E->getArgumentExpr()); 1534 } 1535 1536 return CGF.GetVLASize(VAT); 1537 } 1538 } 1539 1540 // If this isn't sizeof(vla), the result must be constant; use the constant 1541 // folding logic so we don't have to duplicate it here. 1542 Expr::EvalResult Result; 1543 E->Evaluate(Result, CGF.getContext()); 1544 return Builder.getInt(Result.Val.getInt()); 1545} 1546 1547Value *ScalarExprEmitter::VisitUnaryReal(const UnaryOperator *E) { 1548 Expr *Op = E->getSubExpr(); 1549 if (Op->getType()->isAnyComplexType()) { 1550 // If it's an l-value, load through the appropriate subobject l-value. 1551 // Note that we have to ask E because Op might be an l-value that 1552 // this won't work for, e.g. an Obj-C property. 1553 if (E->isGLValue()) 1554 return CGF.EmitLoadOfLValue(CGF.EmitLValue(E), E->getType()) 1555 .getScalarVal(); 1556 1557 // Otherwise, calculate and project. 1558 return CGF.EmitComplexExpr(Op, false, true).first; 1559 } 1560 1561 return Visit(Op); 1562} 1563 1564Value *ScalarExprEmitter::VisitUnaryImag(const UnaryOperator *E) { 1565 Expr *Op = E->getSubExpr(); 1566 if (Op->getType()->isAnyComplexType()) { 1567 // If it's an l-value, load through the appropriate subobject l-value. 1568 // Note that we have to ask E because Op might be an l-value that 1569 // this won't work for, e.g. an Obj-C property. 1570 if (Op->isGLValue()) 1571 return CGF.EmitLoadOfLValue(CGF.EmitLValue(E), E->getType()) 1572 .getScalarVal(); 1573 1574 // Otherwise, calculate and project. 1575 return CGF.EmitComplexExpr(Op, true, false).second; 1576 } 1577 1578 // __imag on a scalar returns zero. Emit the subexpr to ensure side 1579 // effects are evaluated, but not the actual value. 1580 CGF.EmitScalarExpr(Op, true); 1581 return llvm::Constant::getNullValue(ConvertType(E->getType())); 1582} 1583 1584//===----------------------------------------------------------------------===// 1585// Binary Operators 1586//===----------------------------------------------------------------------===// 1587 1588BinOpInfo ScalarExprEmitter::EmitBinOps(const BinaryOperator *E) { 1589 TestAndClearIgnoreResultAssign(); 1590 BinOpInfo Result; 1591 Result.LHS = Visit(E->getLHS()); 1592 Result.RHS = Visit(E->getRHS()); 1593 Result.Ty = E->getType(); 1594 Result.Opcode = E->getOpcode(); 1595 Result.E = E; 1596 return Result; 1597} 1598 1599LValue ScalarExprEmitter::EmitCompoundAssignLValue( 1600 const CompoundAssignOperator *E, 1601 Value *(ScalarExprEmitter::*Func)(const BinOpInfo &), 1602 Value *&Result) { 1603 QualType LHSTy = E->getLHS()->getType(); 1604 BinOpInfo OpInfo; 1605 1606 if (E->getComputationResultType()->isAnyComplexType()) { 1607 // This needs to go through the complex expression emitter, but it's a tad 1608 // complicated to do that... I'm leaving it out for now. (Note that we do 1609 // actually need the imaginary part of the RHS for multiplication and 1610 // division.) 1611 CGF.ErrorUnsupported(E, "complex compound assignment"); 1612 Result = llvm::UndefValue::get(CGF.ConvertType(E->getType())); 1613 return LValue(); 1614 } 1615 1616 // Emit the RHS first. __block variables need to have the rhs evaluated 1617 // first, plus this should improve codegen a little. 1618 OpInfo.RHS = Visit(E->getRHS()); 1619 OpInfo.Ty = E->getComputationResultType(); 1620 OpInfo.Opcode = E->getOpcode(); 1621 OpInfo.E = E; 1622 // Load/convert the LHS. 1623 LValue LHSLV = EmitCheckedLValue(E->getLHS()); 1624 OpInfo.LHS = EmitLoadOfLValue(LHSLV, LHSTy); 1625 OpInfo.LHS = EmitScalarConversion(OpInfo.LHS, LHSTy, 1626 E->getComputationLHSType()); 1627 1628 // Expand the binary operator. 1629 Result = (this->*Func)(OpInfo); 1630 1631 // Convert the result back to the LHS type. 1632 Result = EmitScalarConversion(Result, E->getComputationResultType(), LHSTy); 1633 1634 // Store the result value into the LHS lvalue. Bit-fields are handled 1635 // specially because the result is altered by the store, i.e., [C99 6.5.16p1] 1636 // 'An assignment expression has the value of the left operand after the 1637 // assignment...'. 1638 if (LHSLV.isBitField()) 1639 CGF.EmitStoreThroughBitfieldLValue(RValue::get(Result), LHSLV, LHSTy, 1640 &Result); 1641 else 1642 CGF.EmitStoreThroughLValue(RValue::get(Result), LHSLV, LHSTy); 1643 1644 return LHSLV; 1645} 1646 1647Value *ScalarExprEmitter::EmitCompoundAssign(const CompoundAssignOperator *E, 1648 Value *(ScalarExprEmitter::*Func)(const BinOpInfo &)) { 1649 bool Ignore = TestAndClearIgnoreResultAssign(); 1650 Value *RHS; 1651 LValue LHS = EmitCompoundAssignLValue(E, Func, RHS); 1652 1653 // If the result is clearly ignored, return now. 1654 if (Ignore) 1655 return 0; 1656 1657 // The result of an assignment in C is the assigned r-value. 1658 if (!CGF.getContext().getLangOptions().CPlusPlus) 1659 return RHS; 1660 1661 // Objective-C property assignment never reloads the value following a store. 1662 if (LHS.isPropertyRef()) 1663 return RHS; 1664 1665 // If the lvalue is non-volatile, return the computed value of the assignment. 1666 if (!LHS.isVolatileQualified()) 1667 return RHS; 1668 1669 // Otherwise, reload the value. 1670 return EmitLoadOfLValue(LHS, E->getType()); 1671} 1672 1673void ScalarExprEmitter::EmitUndefinedBehaviorIntegerDivAndRemCheck( 1674 const BinOpInfo &Ops, 1675 llvm::Value *Zero, bool isDiv) { 1676 llvm::BasicBlock *overflowBB = CGF.createBasicBlock("overflow", CGF.CurFn); 1677 llvm::BasicBlock *contBB = 1678 CGF.createBasicBlock(isDiv ? "div.cont" : "rem.cont", CGF.CurFn); 1679 1680 const llvm::IntegerType *Ty = cast<llvm::IntegerType>(Zero->getType()); 1681 1682 if (Ops.Ty->hasSignedIntegerRepresentation()) { 1683 llvm::Value *IntMin = 1684 Builder.getInt(llvm::APInt::getSignedMinValue(Ty->getBitWidth())); 1685 llvm::Value *NegOne = llvm::ConstantInt::get(Ty, -1ULL); 1686 1687 llvm::Value *Cond1 = Builder.CreateICmpEQ(Ops.RHS, Zero); 1688 llvm::Value *LHSCmp = Builder.CreateICmpEQ(Ops.LHS, IntMin); 1689 llvm::Value *RHSCmp = Builder.CreateICmpEQ(Ops.RHS, NegOne); 1690 llvm::Value *Cond2 = Builder.CreateAnd(LHSCmp, RHSCmp, "and"); 1691 Builder.CreateCondBr(Builder.CreateOr(Cond1, Cond2, "or"), 1692 overflowBB, contBB); 1693 } else { 1694 CGF.Builder.CreateCondBr(Builder.CreateICmpEQ(Ops.RHS, Zero), 1695 overflowBB, contBB); 1696 } 1697 EmitOverflowBB(overflowBB); 1698 Builder.SetInsertPoint(contBB); 1699} 1700 1701Value *ScalarExprEmitter::EmitDiv(const BinOpInfo &Ops) { 1702 if (isTrapvOverflowBehavior()) { 1703 llvm::Value *Zero = llvm::Constant::getNullValue(ConvertType(Ops.Ty)); 1704 1705 if (Ops.Ty->isIntegerType()) 1706 EmitUndefinedBehaviorIntegerDivAndRemCheck(Ops, Zero, true); 1707 else if (Ops.Ty->isRealFloatingType()) { 1708 llvm::BasicBlock *overflowBB = CGF.createBasicBlock("overflow", 1709 CGF.CurFn); 1710 llvm::BasicBlock *DivCont = CGF.createBasicBlock("div.cont", CGF.CurFn); 1711 CGF.Builder.CreateCondBr(Builder.CreateFCmpOEQ(Ops.RHS, Zero), 1712 overflowBB, DivCont); 1713 EmitOverflowBB(overflowBB); 1714 Builder.SetInsertPoint(DivCont); 1715 } 1716 } 1717 if (Ops.LHS->getType()->isFPOrFPVectorTy()) 1718 return Builder.CreateFDiv(Ops.LHS, Ops.RHS, "div"); 1719 else if (Ops.Ty->hasUnsignedIntegerRepresentation()) 1720 return Builder.CreateUDiv(Ops.LHS, Ops.RHS, "div"); 1721 else 1722 return Builder.CreateSDiv(Ops.LHS, Ops.RHS, "div"); 1723} 1724 1725Value *ScalarExprEmitter::EmitRem(const BinOpInfo &Ops) { 1726 // Rem in C can't be a floating point type: C99 6.5.5p2. 1727 if (isTrapvOverflowBehavior()) { 1728 llvm::Value *Zero = llvm::Constant::getNullValue(ConvertType(Ops.Ty)); 1729 1730 if (Ops.Ty->isIntegerType()) 1731 EmitUndefinedBehaviorIntegerDivAndRemCheck(Ops, Zero, false); 1732 } 1733 1734 if (Ops.Ty->hasUnsignedIntegerRepresentation()) 1735 return Builder.CreateURem(Ops.LHS, Ops.RHS, "rem"); 1736 else 1737 return Builder.CreateSRem(Ops.LHS, Ops.RHS, "rem"); 1738} 1739 1740Value *ScalarExprEmitter::EmitOverflowCheckedBinOp(const BinOpInfo &Ops) { 1741 unsigned IID; 1742 unsigned OpID = 0; 1743 1744 switch (Ops.Opcode) { 1745 case BO_Add: 1746 case BO_AddAssign: 1747 OpID = 1; 1748 IID = llvm::Intrinsic::sadd_with_overflow; 1749 break; 1750 case BO_Sub: 1751 case BO_SubAssign: 1752 OpID = 2; 1753 IID = llvm::Intrinsic::ssub_with_overflow; 1754 break; 1755 case BO_Mul: 1756 case BO_MulAssign: 1757 OpID = 3; 1758 IID = llvm::Intrinsic::smul_with_overflow; 1759 break; 1760 default: 1761 assert(false && "Unsupported operation for overflow detection"); 1762 IID = 0; 1763 } 1764 OpID <<= 1; 1765 OpID |= 1; 1766 1767 const llvm::Type *opTy = CGF.CGM.getTypes().ConvertType(Ops.Ty); 1768 1769 llvm::Function *intrinsic = CGF.CGM.getIntrinsic(IID, &opTy, 1); 1770 1771 Value *resultAndOverflow = Builder.CreateCall2(intrinsic, Ops.LHS, Ops.RHS); 1772 Value *result = Builder.CreateExtractValue(resultAndOverflow, 0); 1773 Value *overflow = Builder.CreateExtractValue(resultAndOverflow, 1); 1774 1775 // Branch in case of overflow. 1776 llvm::BasicBlock *initialBB = Builder.GetInsertBlock(); 1777 llvm::BasicBlock *overflowBB = CGF.createBasicBlock("overflow", CGF.CurFn); 1778 llvm::BasicBlock *continueBB = CGF.createBasicBlock("nooverflow", CGF.CurFn); 1779 1780 Builder.CreateCondBr(overflow, overflowBB, continueBB); 1781 1782 // Handle overflow with llvm.trap. 1783 const std::string *handlerName = 1784 &CGF.getContext().getLangOptions().OverflowHandler; 1785 if (handlerName->empty()) { 1786 EmitOverflowBB(overflowBB); 1787 Builder.SetInsertPoint(continueBB); 1788 return result; 1789 } 1790 1791 // If an overflow handler is set, then we want to call it and then use its 1792 // result, if it returns. 1793 Builder.SetInsertPoint(overflowBB); 1794 1795 // Get the overflow handler. 1796 const llvm::Type *Int8Ty = llvm::Type::getInt8Ty(VMContext); 1797 std::vector<const llvm::Type*> argTypes; 1798 argTypes.push_back(CGF.Int64Ty); argTypes.push_back(CGF.Int64Ty); 1799 argTypes.push_back(Int8Ty); argTypes.push_back(Int8Ty); 1800 llvm::FunctionType *handlerTy = 1801 llvm::FunctionType::get(CGF.Int64Ty, argTypes, true); 1802 llvm::Value *handler = CGF.CGM.CreateRuntimeFunction(handlerTy, *handlerName); 1803 1804 // Sign extend the args to 64-bit, so that we can use the same handler for 1805 // all types of overflow. 1806 llvm::Value *lhs = Builder.CreateSExt(Ops.LHS, CGF.Int64Ty); 1807 llvm::Value *rhs = Builder.CreateSExt(Ops.RHS, CGF.Int64Ty); 1808 1809 // Call the handler with the two arguments, the operation, and the size of 1810 // the result. 1811 llvm::Value *handlerResult = Builder.CreateCall4(handler, lhs, rhs, 1812 Builder.getInt8(OpID), 1813 Builder.getInt8(cast<llvm::IntegerType>(opTy)->getBitWidth())); 1814 1815 // Truncate the result back to the desired size. 1816 handlerResult = Builder.CreateTrunc(handlerResult, opTy); 1817 Builder.CreateBr(continueBB); 1818 1819 Builder.SetInsertPoint(continueBB); 1820 llvm::PHINode *phi = Builder.CreatePHI(opTy, 2); 1821 phi->addIncoming(result, initialBB); 1822 phi->addIncoming(handlerResult, overflowBB); 1823 1824 return phi; 1825} 1826 1827Value *ScalarExprEmitter::EmitAdd(const BinOpInfo &Ops) { 1828 if (!Ops.Ty->isAnyPointerType()) { 1829 if (Ops.Ty->isSignedIntegerType()) { 1830 switch (CGF.getContext().getLangOptions().getSignedOverflowBehavior()) { 1831 case LangOptions::SOB_Undefined: 1832 return Builder.CreateNSWAdd(Ops.LHS, Ops.RHS, "add"); 1833 case LangOptions::SOB_Defined: 1834 return Builder.CreateAdd(Ops.LHS, Ops.RHS, "add"); 1835 case LangOptions::SOB_Trapping: 1836 return EmitOverflowCheckedBinOp(Ops); 1837 } 1838 } 1839 1840 if (Ops.LHS->getType()->isFPOrFPVectorTy()) 1841 return Builder.CreateFAdd(Ops.LHS, Ops.RHS, "add"); 1842 1843 return Builder.CreateAdd(Ops.LHS, Ops.RHS, "add"); 1844 } 1845 1846 // Must have binary (not unary) expr here. Unary pointer decrement doesn't 1847 // use this path. 1848 const BinaryOperator *BinOp = cast<BinaryOperator>(Ops.E); 1849 1850 if (Ops.Ty->isPointerType() && 1851 Ops.Ty->getAs<PointerType>()->isVariableArrayType()) { 1852 // The amount of the addition needs to account for the VLA size 1853 CGF.ErrorUnsupported(BinOp, "VLA pointer addition"); 1854 } 1855 1856 Value *Ptr, *Idx; 1857 Expr *IdxExp; 1858 const PointerType *PT = BinOp->getLHS()->getType()->getAs<PointerType>(); 1859 const ObjCObjectPointerType *OPT = 1860 BinOp->getLHS()->getType()->getAs<ObjCObjectPointerType>(); 1861 if (PT || OPT) { 1862 Ptr = Ops.LHS; 1863 Idx = Ops.RHS; 1864 IdxExp = BinOp->getRHS(); 1865 } else { // int + pointer 1866 PT = BinOp->getRHS()->getType()->getAs<PointerType>(); 1867 OPT = BinOp->getRHS()->getType()->getAs<ObjCObjectPointerType>(); 1868 assert((PT || OPT) && "Invalid add expr"); 1869 Ptr = Ops.RHS; 1870 Idx = Ops.LHS; 1871 IdxExp = BinOp->getLHS(); 1872 } 1873 1874 unsigned Width = cast<llvm::IntegerType>(Idx->getType())->getBitWidth(); 1875 if (Width < CGF.PointerWidthInBits) { 1876 // Zero or sign extend the pointer value based on whether the index is 1877 // signed or not. 1878 const llvm::Type *IdxType = CGF.IntPtrTy; 1879 if (IdxExp->getType()->isSignedIntegerType()) 1880 Idx = Builder.CreateSExt(Idx, IdxType, "idx.ext"); 1881 else 1882 Idx = Builder.CreateZExt(Idx, IdxType, "idx.ext"); 1883 } 1884 const QualType ElementType = PT ? PT->getPointeeType() : OPT->getPointeeType(); 1885 // Handle interface types, which are not represented with a concrete type. 1886 if (const ObjCObjectType *OIT = ElementType->getAs<ObjCObjectType>()) { 1887 llvm::Value *InterfaceSize = 1888 llvm::ConstantInt::get(Idx->getType(), 1889 CGF.getContext().getTypeSizeInChars(OIT).getQuantity()); 1890 Idx = Builder.CreateMul(Idx, InterfaceSize); 1891 const llvm::Type *i8Ty = llvm::Type::getInt8PtrTy(VMContext); 1892 Value *Casted = Builder.CreateBitCast(Ptr, i8Ty); 1893 Value *Res = Builder.CreateGEP(Casted, Idx, "add.ptr"); 1894 return Builder.CreateBitCast(Res, Ptr->getType()); 1895 } 1896 1897 // Explicitly handle GNU void* and function pointer arithmetic extensions. The 1898 // GNU void* casts amount to no-ops since our void* type is i8*, but this is 1899 // future proof. 1900 if (ElementType->isVoidType() || ElementType->isFunctionType()) { 1901 const llvm::Type *i8Ty = llvm::Type::getInt8PtrTy(VMContext); 1902 Value *Casted = Builder.CreateBitCast(Ptr, i8Ty); 1903 Value *Res = Builder.CreateGEP(Casted, Idx, "add.ptr"); 1904 return Builder.CreateBitCast(Res, Ptr->getType()); 1905 } 1906 1907 if (CGF.getContext().getLangOptions().isSignedOverflowDefined()) 1908 return Builder.CreateGEP(Ptr, Idx, "add.ptr"); 1909 return Builder.CreateInBoundsGEP(Ptr, Idx, "add.ptr"); 1910} 1911 1912Value *ScalarExprEmitter::EmitSub(const BinOpInfo &Ops) { 1913 if (!isa<llvm::PointerType>(Ops.LHS->getType())) { 1914 if (Ops.Ty->isSignedIntegerType()) { 1915 switch (CGF.getContext().getLangOptions().getSignedOverflowBehavior()) { 1916 case LangOptions::SOB_Undefined: 1917 return Builder.CreateNSWSub(Ops.LHS, Ops.RHS, "sub"); 1918 case LangOptions::SOB_Defined: 1919 return Builder.CreateSub(Ops.LHS, Ops.RHS, "sub"); 1920 case LangOptions::SOB_Trapping: 1921 return EmitOverflowCheckedBinOp(Ops); 1922 } 1923 } 1924 1925 if (Ops.LHS->getType()->isFPOrFPVectorTy()) 1926 return Builder.CreateFSub(Ops.LHS, Ops.RHS, "sub"); 1927 1928 return Builder.CreateSub(Ops.LHS, Ops.RHS, "sub"); 1929 } 1930 1931 // Must have binary (not unary) expr here. Unary pointer increment doesn't 1932 // use this path. 1933 const BinaryOperator *BinOp = cast<BinaryOperator>(Ops.E); 1934 1935 if (BinOp->getLHS()->getType()->isPointerType() && 1936 BinOp->getLHS()->getType()->getAs<PointerType>()->isVariableArrayType()) { 1937 // The amount of the addition needs to account for the VLA size for 1938 // ptr-int 1939 // The amount of the division needs to account for the VLA size for 1940 // ptr-ptr. 1941 CGF.ErrorUnsupported(BinOp, "VLA pointer subtraction"); 1942 } 1943 1944 const QualType LHSType = BinOp->getLHS()->getType(); 1945 const QualType LHSElementType = LHSType->getPointeeType(); 1946 if (!isa<llvm::PointerType>(Ops.RHS->getType())) { 1947 // pointer - int 1948 Value *Idx = Ops.RHS; 1949 unsigned Width = cast<llvm::IntegerType>(Idx->getType())->getBitWidth(); 1950 if (Width < CGF.PointerWidthInBits) { 1951 // Zero or sign extend the pointer value based on whether the index is 1952 // signed or not. 1953 const llvm::Type *IdxType = CGF.IntPtrTy; 1954 if (BinOp->getRHS()->getType()->isSignedIntegerType()) 1955 Idx = Builder.CreateSExt(Idx, IdxType, "idx.ext"); 1956 else 1957 Idx = Builder.CreateZExt(Idx, IdxType, "idx.ext"); 1958 } 1959 Idx = Builder.CreateNeg(Idx, "sub.ptr.neg"); 1960 1961 // Handle interface types, which are not represented with a concrete type. 1962 if (const ObjCObjectType *OIT = LHSElementType->getAs<ObjCObjectType>()) { 1963 llvm::Value *InterfaceSize = 1964 llvm::ConstantInt::get(Idx->getType(), 1965 CGF.getContext(). 1966 getTypeSizeInChars(OIT).getQuantity()); 1967 Idx = Builder.CreateMul(Idx, InterfaceSize); 1968 const llvm::Type *i8Ty = llvm::Type::getInt8PtrTy(VMContext); 1969 Value *LHSCasted = Builder.CreateBitCast(Ops.LHS, i8Ty); 1970 Value *Res = Builder.CreateGEP(LHSCasted, Idx, "add.ptr"); 1971 return Builder.CreateBitCast(Res, Ops.LHS->getType()); 1972 } 1973 1974 // Explicitly handle GNU void* and function pointer arithmetic 1975 // extensions. The GNU void* casts amount to no-ops since our void* type is 1976 // i8*, but this is future proof. 1977 if (LHSElementType->isVoidType() || LHSElementType->isFunctionType()) { 1978 const llvm::Type *i8Ty = llvm::Type::getInt8PtrTy(VMContext); 1979 Value *LHSCasted = Builder.CreateBitCast(Ops.LHS, i8Ty); 1980 Value *Res = Builder.CreateGEP(LHSCasted, Idx, "sub.ptr"); 1981 return Builder.CreateBitCast(Res, Ops.LHS->getType()); 1982 } 1983 1984 if (CGF.getContext().getLangOptions().isSignedOverflowDefined()) 1985 return Builder.CreateGEP(Ops.LHS, Idx, "sub.ptr"); 1986 return Builder.CreateInBoundsGEP(Ops.LHS, Idx, "sub.ptr"); 1987 } 1988 1989 // pointer - pointer 1990 Value *LHS = Ops.LHS; 1991 Value *RHS = Ops.RHS; 1992 1993 CharUnits ElementSize; 1994 1995 // Handle GCC extension for pointer arithmetic on void* and function pointer 1996 // types. 1997 if (LHSElementType->isVoidType() || LHSElementType->isFunctionType()) 1998 ElementSize = CharUnits::One(); 1999 else 2000 ElementSize = CGF.getContext().getTypeSizeInChars(LHSElementType); 2001 2002 const llvm::Type *ResultType = ConvertType(Ops.Ty); 2003 LHS = Builder.CreatePtrToInt(LHS, ResultType, "sub.ptr.lhs.cast"); 2004 RHS = Builder.CreatePtrToInt(RHS, ResultType, "sub.ptr.rhs.cast"); 2005 Value *BytesBetween = Builder.CreateSub(LHS, RHS, "sub.ptr.sub"); 2006 2007 // Optimize out the shift for element size of 1. 2008 if (ElementSize.isOne()) 2009 return BytesBetween; 2010 2011 // Otherwise, do a full sdiv. This uses the "exact" form of sdiv, since 2012 // pointer difference in C is only defined in the case where both operands 2013 // are pointing to elements of an array. 2014 Value *BytesPerElt = 2015 llvm::ConstantInt::get(ResultType, ElementSize.getQuantity()); 2016 return Builder.CreateExactSDiv(BytesBetween, BytesPerElt, "sub.ptr.div"); 2017} 2018 2019Value *ScalarExprEmitter::EmitShl(const BinOpInfo &Ops) { 2020 // LLVM requires the LHS and RHS to be the same type: promote or truncate the 2021 // RHS to the same size as the LHS. 2022 Value *RHS = Ops.RHS; 2023 if (Ops.LHS->getType() != RHS->getType()) 2024 RHS = Builder.CreateIntCast(RHS, Ops.LHS->getType(), false, "sh_prom"); 2025 2026 if (CGF.CatchUndefined 2027 && isa<llvm::IntegerType>(Ops.LHS->getType())) { 2028 unsigned Width = cast<llvm::IntegerType>(Ops.LHS->getType())->getBitWidth(); 2029 llvm::BasicBlock *Cont = CGF.createBasicBlock("cont"); 2030 CGF.Builder.CreateCondBr(Builder.CreateICmpULT(RHS, 2031 llvm::ConstantInt::get(RHS->getType(), Width)), 2032 Cont, CGF.getTrapBB()); 2033 CGF.EmitBlock(Cont); 2034 } 2035 2036 return Builder.CreateShl(Ops.LHS, RHS, "shl"); 2037} 2038 2039Value *ScalarExprEmitter::EmitShr(const BinOpInfo &Ops) { 2040 // LLVM requires the LHS and RHS to be the same type: promote or truncate the 2041 // RHS to the same size as the LHS. 2042 Value *RHS = Ops.RHS; 2043 if (Ops.LHS->getType() != RHS->getType()) 2044 RHS = Builder.CreateIntCast(RHS, Ops.LHS->getType(), false, "sh_prom"); 2045 2046 if (CGF.CatchUndefined 2047 && isa<llvm::IntegerType>(Ops.LHS->getType())) { 2048 unsigned Width = cast<llvm::IntegerType>(Ops.LHS->getType())->getBitWidth(); 2049 llvm::BasicBlock *Cont = CGF.createBasicBlock("cont"); 2050 CGF.Builder.CreateCondBr(Builder.CreateICmpULT(RHS, 2051 llvm::ConstantInt::get(RHS->getType(), Width)), 2052 Cont, CGF.getTrapBB()); 2053 CGF.EmitBlock(Cont); 2054 } 2055 2056 if (Ops.Ty->hasUnsignedIntegerRepresentation()) 2057 return Builder.CreateLShr(Ops.LHS, RHS, "shr"); 2058 return Builder.CreateAShr(Ops.LHS, RHS, "shr"); 2059} 2060 2061enum IntrinsicType { VCMPEQ, VCMPGT }; 2062// return corresponding comparison intrinsic for given vector type 2063static llvm::Intrinsic::ID GetIntrinsic(IntrinsicType IT, 2064 BuiltinType::Kind ElemKind) { 2065 switch (ElemKind) { 2066 default: assert(0 && "unexpected element type"); 2067 case BuiltinType::Char_U: 2068 case BuiltinType::UChar: 2069 return (IT == VCMPEQ) ? llvm::Intrinsic::ppc_altivec_vcmpequb_p : 2070 llvm::Intrinsic::ppc_altivec_vcmpgtub_p; 2071 break; 2072 case BuiltinType::Char_S: 2073 case BuiltinType::SChar: 2074 return (IT == VCMPEQ) ? llvm::Intrinsic::ppc_altivec_vcmpequb_p : 2075 llvm::Intrinsic::ppc_altivec_vcmpgtsb_p; 2076 break; 2077 case BuiltinType::UShort: 2078 return (IT == VCMPEQ) ? llvm::Intrinsic::ppc_altivec_vcmpequh_p : 2079 llvm::Intrinsic::ppc_altivec_vcmpgtuh_p; 2080 break; 2081 case BuiltinType::Short: 2082 return (IT == VCMPEQ) ? llvm::Intrinsic::ppc_altivec_vcmpequh_p : 2083 llvm::Intrinsic::ppc_altivec_vcmpgtsh_p; 2084 break; 2085 case BuiltinType::UInt: 2086 case BuiltinType::ULong: 2087 return (IT == VCMPEQ) ? llvm::Intrinsic::ppc_altivec_vcmpequw_p : 2088 llvm::Intrinsic::ppc_altivec_vcmpgtuw_p; 2089 break; 2090 case BuiltinType::Int: 2091 case BuiltinType::Long: 2092 return (IT == VCMPEQ) ? llvm::Intrinsic::ppc_altivec_vcmpequw_p : 2093 llvm::Intrinsic::ppc_altivec_vcmpgtsw_p; 2094 break; 2095 case BuiltinType::Float: 2096 return (IT == VCMPEQ) ? llvm::Intrinsic::ppc_altivec_vcmpeqfp_p : 2097 llvm::Intrinsic::ppc_altivec_vcmpgtfp_p; 2098 break; 2099 } 2100 return llvm::Intrinsic::not_intrinsic; 2101} 2102 2103Value *ScalarExprEmitter::EmitCompare(const BinaryOperator *E,unsigned UICmpOpc, 2104 unsigned SICmpOpc, unsigned FCmpOpc) { 2105 TestAndClearIgnoreResultAssign(); 2106 Value *Result; 2107 QualType LHSTy = E->getLHS()->getType(); 2108 if (const MemberPointerType *MPT = LHSTy->getAs<MemberPointerType>()) { 2109 assert(E->getOpcode() == BO_EQ || 2110 E->getOpcode() == BO_NE); 2111 Value *LHS = CGF.EmitScalarExpr(E->getLHS()); 2112 Value *RHS = CGF.EmitScalarExpr(E->getRHS()); 2113 Result = CGF.CGM.getCXXABI().EmitMemberPointerComparison( 2114 CGF, LHS, RHS, MPT, E->getOpcode() == BO_NE); 2115 } else if (!LHSTy->isAnyComplexType()) { 2116 Value *LHS = Visit(E->getLHS()); 2117 Value *RHS = Visit(E->getRHS()); 2118 2119 // If AltiVec, the comparison results in a numeric type, so we use 2120 // intrinsics comparing vectors and giving 0 or 1 as a result 2121 if (LHSTy->isVectorType() && !E->getType()->isVectorType()) { 2122 // constants for mapping CR6 register bits to predicate result 2123 enum { CR6_EQ=0, CR6_EQ_REV, CR6_LT, CR6_LT_REV } CR6; 2124 2125 llvm::Intrinsic::ID ID = llvm::Intrinsic::not_intrinsic; 2126 2127 // in several cases vector arguments order will be reversed 2128 Value *FirstVecArg = LHS, 2129 *SecondVecArg = RHS; 2130 2131 QualType ElTy = LHSTy->getAs<VectorType>()->getElementType(); 2132 const BuiltinType *BTy = ElTy->getAs<BuiltinType>(); 2133 BuiltinType::Kind ElementKind = BTy->getKind(); 2134 2135 switch(E->getOpcode()) { 2136 default: assert(0 && "is not a comparison operation"); 2137 case BO_EQ: 2138 CR6 = CR6_LT; 2139 ID = GetIntrinsic(VCMPEQ, ElementKind); 2140 break; 2141 case BO_NE: 2142 CR6 = CR6_EQ; 2143 ID = GetIntrinsic(VCMPEQ, ElementKind); 2144 break; 2145 case BO_LT: 2146 CR6 = CR6_LT; 2147 ID = GetIntrinsic(VCMPGT, ElementKind); 2148 std::swap(FirstVecArg, SecondVecArg); 2149 break; 2150 case BO_GT: 2151 CR6 = CR6_LT; 2152 ID = GetIntrinsic(VCMPGT, ElementKind); 2153 break; 2154 case BO_LE: 2155 if (ElementKind == BuiltinType::Float) { 2156 CR6 = CR6_LT; 2157 ID = llvm::Intrinsic::ppc_altivec_vcmpgefp_p; 2158 std::swap(FirstVecArg, SecondVecArg); 2159 } 2160 else { 2161 CR6 = CR6_EQ; 2162 ID = GetIntrinsic(VCMPGT, ElementKind); 2163 } 2164 break; 2165 case BO_GE: 2166 if (ElementKind == BuiltinType::Float) { 2167 CR6 = CR6_LT; 2168 ID = llvm::Intrinsic::ppc_altivec_vcmpgefp_p; 2169 } 2170 else { 2171 CR6 = CR6_EQ; 2172 ID = GetIntrinsic(VCMPGT, ElementKind); 2173 std::swap(FirstVecArg, SecondVecArg); 2174 } 2175 break; 2176 } 2177 2178 Value *CR6Param = Builder.getInt32(CR6); 2179 llvm::Function *F = CGF.CGM.getIntrinsic(ID); 2180 Result = Builder.CreateCall3(F, CR6Param, FirstVecArg, SecondVecArg, ""); 2181 return EmitScalarConversion(Result, CGF.getContext().BoolTy, E->getType()); 2182 } 2183 2184 if (LHS->getType()->isFPOrFPVectorTy()) { 2185 Result = Builder.CreateFCmp((llvm::CmpInst::Predicate)FCmpOpc, 2186 LHS, RHS, "cmp"); 2187 } else if (LHSTy->hasSignedIntegerRepresentation()) { 2188 Result = Builder.CreateICmp((llvm::ICmpInst::Predicate)SICmpOpc, 2189 LHS, RHS, "cmp"); 2190 } else { 2191 // Unsigned integers and pointers. 2192 Result = Builder.CreateICmp((llvm::ICmpInst::Predicate)UICmpOpc, 2193 LHS, RHS, "cmp"); 2194 } 2195 2196 // If this is a vector comparison, sign extend the result to the appropriate 2197 // vector integer type and return it (don't convert to bool). 2198 if (LHSTy->isVectorType()) 2199 return Builder.CreateSExt(Result, ConvertType(E->getType()), "sext"); 2200 2201 } else { 2202 // Complex Comparison: can only be an equality comparison. 2203 CodeGenFunction::ComplexPairTy LHS = CGF.EmitComplexExpr(E->getLHS()); 2204 CodeGenFunction::ComplexPairTy RHS = CGF.EmitComplexExpr(E->getRHS()); 2205 2206 QualType CETy = LHSTy->getAs<ComplexType>()->getElementType(); 2207 2208 Value *ResultR, *ResultI; 2209 if (CETy->isRealFloatingType()) { 2210 ResultR = Builder.CreateFCmp((llvm::FCmpInst::Predicate)FCmpOpc, 2211 LHS.first, RHS.first, "cmp.r"); 2212 ResultI = Builder.CreateFCmp((llvm::FCmpInst::Predicate)FCmpOpc, 2213 LHS.second, RHS.second, "cmp.i"); 2214 } else { 2215 // Complex comparisons can only be equality comparisons. As such, signed 2216 // and unsigned opcodes are the same. 2217 ResultR = Builder.CreateICmp((llvm::ICmpInst::Predicate)UICmpOpc, 2218 LHS.first, RHS.first, "cmp.r"); 2219 ResultI = Builder.CreateICmp((llvm::ICmpInst::Predicate)UICmpOpc, 2220 LHS.second, RHS.second, "cmp.i"); 2221 } 2222 2223 if (E->getOpcode() == BO_EQ) { 2224 Result = Builder.CreateAnd(ResultR, ResultI, "and.ri"); 2225 } else { 2226 assert(E->getOpcode() == BO_NE && 2227 "Complex comparison other than == or != ?"); 2228 Result = Builder.CreateOr(ResultR, ResultI, "or.ri"); 2229 } 2230 } 2231 2232 return EmitScalarConversion(Result, CGF.getContext().BoolTy, E->getType()); 2233} 2234 2235Value *ScalarExprEmitter::VisitBinAssign(const BinaryOperator *E) { 2236 bool Ignore = TestAndClearIgnoreResultAssign(); 2237 2238 // __block variables need to have the rhs evaluated first, plus this should 2239 // improve codegen just a little. 2240 Value *RHS = Visit(E->getRHS()); 2241 LValue LHS = EmitCheckedLValue(E->getLHS()); 2242 2243 // Store the value into the LHS. Bit-fields are handled specially 2244 // because the result is altered by the store, i.e., [C99 6.5.16p1] 2245 // 'An assignment expression has the value of the left operand after 2246 // the assignment...'. 2247 if (LHS.isBitField()) 2248 CGF.EmitStoreThroughBitfieldLValue(RValue::get(RHS), LHS, E->getType(), 2249 &RHS); 2250 else 2251 CGF.EmitStoreThroughLValue(RValue::get(RHS), LHS, E->getType()); 2252 2253 // If the result is clearly ignored, return now. 2254 if (Ignore) 2255 return 0; 2256 2257 // The result of an assignment in C is the assigned r-value. 2258 if (!CGF.getContext().getLangOptions().CPlusPlus) 2259 return RHS; 2260 2261 // Objective-C property assignment never reloads the value following a store. 2262 if (LHS.isPropertyRef()) 2263 return RHS; 2264 2265 // If the lvalue is non-volatile, return the computed value of the assignment. 2266 if (!LHS.isVolatileQualified()) 2267 return RHS; 2268 2269 // Otherwise, reload the value. 2270 return EmitLoadOfLValue(LHS, E->getType()); 2271} 2272 2273Value *ScalarExprEmitter::VisitBinLAnd(const BinaryOperator *E) { 2274 const llvm::Type *ResTy = ConvertType(E->getType()); 2275 2276 // If we have 0 && RHS, see if we can elide RHS, if so, just return 0. 2277 // If we have 1 && X, just emit X without inserting the control flow. 2278 bool LHSCondVal; 2279 if (CGF.ConstantFoldsToSimpleInteger(E->getLHS(), LHSCondVal)) { 2280 if (LHSCondVal) { // If we have 1 && X, just emit X. 2281 Value *RHSCond = CGF.EvaluateExprAsBool(E->getRHS()); 2282 // ZExt result to int or bool. 2283 return Builder.CreateZExtOrBitCast(RHSCond, ResTy, "land.ext"); 2284 } 2285 2286 // 0 && RHS: If it is safe, just elide the RHS, and return 0/false. 2287 if (!CGF.ContainsLabel(E->getRHS())) 2288 return llvm::Constant::getNullValue(ResTy); 2289 } 2290 2291 llvm::BasicBlock *ContBlock = CGF.createBasicBlock("land.end"); 2292 llvm::BasicBlock *RHSBlock = CGF.createBasicBlock("land.rhs"); 2293 2294 CodeGenFunction::ConditionalEvaluation eval(CGF); 2295 2296 // Branch on the LHS first. If it is false, go to the failure (cont) block. 2297 CGF.EmitBranchOnBoolExpr(E->getLHS(), RHSBlock, ContBlock); 2298 2299 // Any edges into the ContBlock are now from an (indeterminate number of) 2300 // edges from this first condition. All of these values will be false. Start 2301 // setting up the PHI node in the Cont Block for this. 2302 llvm::PHINode *PN = llvm::PHINode::Create(llvm::Type::getInt1Ty(VMContext), 2, 2303 "", ContBlock); 2304 for (llvm::pred_iterator PI = pred_begin(ContBlock), PE = pred_end(ContBlock); 2305 PI != PE; ++PI) 2306 PN->addIncoming(llvm::ConstantInt::getFalse(VMContext), *PI); 2307 2308 eval.begin(CGF); 2309 CGF.EmitBlock(RHSBlock); 2310 Value *RHSCond = CGF.EvaluateExprAsBool(E->getRHS()); 2311 eval.end(CGF); 2312 2313 // Reaquire the RHS block, as there may be subblocks inserted. 2314 RHSBlock = Builder.GetInsertBlock(); 2315 2316 // Emit an unconditional branch from this block to ContBlock. Insert an entry 2317 // into the phi node for the edge with the value of RHSCond. 2318 if (CGF.getDebugInfo()) 2319 // There is no need to emit line number for unconditional branch. 2320 Builder.SetCurrentDebugLocation(llvm::DebugLoc()); 2321 CGF.EmitBlock(ContBlock); 2322 PN->addIncoming(RHSCond, RHSBlock); 2323 2324 // ZExt result to int. 2325 return Builder.CreateZExtOrBitCast(PN, ResTy, "land.ext"); 2326} 2327 2328Value *ScalarExprEmitter::VisitBinLOr(const BinaryOperator *E) { 2329 const llvm::Type *ResTy = ConvertType(E->getType()); 2330 2331 // If we have 1 || RHS, see if we can elide RHS, if so, just return 1. 2332 // If we have 0 || X, just emit X without inserting the control flow. 2333 bool LHSCondVal; 2334 if (CGF.ConstantFoldsToSimpleInteger(E->getLHS(), LHSCondVal)) { 2335 if (!LHSCondVal) { // If we have 0 || X, just emit X. 2336 Value *RHSCond = CGF.EvaluateExprAsBool(E->getRHS()); 2337 // ZExt result to int or bool. 2338 return Builder.CreateZExtOrBitCast(RHSCond, ResTy, "lor.ext"); 2339 } 2340 2341 // 1 || RHS: If it is safe, just elide the RHS, and return 1/true. 2342 if (!CGF.ContainsLabel(E->getRHS())) 2343 return llvm::ConstantInt::get(ResTy, 1); 2344 } 2345 2346 llvm::BasicBlock *ContBlock = CGF.createBasicBlock("lor.end"); 2347 llvm::BasicBlock *RHSBlock = CGF.createBasicBlock("lor.rhs"); 2348 2349 CodeGenFunction::ConditionalEvaluation eval(CGF); 2350 2351 // Branch on the LHS first. If it is true, go to the success (cont) block. 2352 CGF.EmitBranchOnBoolExpr(E->getLHS(), ContBlock, RHSBlock); 2353 2354 // Any edges into the ContBlock are now from an (indeterminate number of) 2355 // edges from this first condition. All of these values will be true. Start 2356 // setting up the PHI node in the Cont Block for this. 2357 llvm::PHINode *PN = llvm::PHINode::Create(llvm::Type::getInt1Ty(VMContext), 2, 2358 "", ContBlock); 2359 for (llvm::pred_iterator PI = pred_begin(ContBlock), PE = pred_end(ContBlock); 2360 PI != PE; ++PI) 2361 PN->addIncoming(llvm::ConstantInt::getTrue(VMContext), *PI); 2362 2363 eval.begin(CGF); 2364 2365 // Emit the RHS condition as a bool value. 2366 CGF.EmitBlock(RHSBlock); 2367 Value *RHSCond = CGF.EvaluateExprAsBool(E->getRHS()); 2368 2369 eval.end(CGF); 2370 2371 // Reaquire the RHS block, as there may be subblocks inserted. 2372 RHSBlock = Builder.GetInsertBlock(); 2373 2374 // Emit an unconditional branch from this block to ContBlock. Insert an entry 2375 // into the phi node for the edge with the value of RHSCond. 2376 CGF.EmitBlock(ContBlock); 2377 PN->addIncoming(RHSCond, RHSBlock); 2378 2379 // ZExt result to int. 2380 return Builder.CreateZExtOrBitCast(PN, ResTy, "lor.ext"); 2381} 2382 2383Value *ScalarExprEmitter::VisitBinComma(const BinaryOperator *E) { 2384 CGF.EmitIgnoredExpr(E->getLHS()); 2385 CGF.EnsureInsertPoint(); 2386 return Visit(E->getRHS()); 2387} 2388 2389//===----------------------------------------------------------------------===// 2390// Other Operators 2391//===----------------------------------------------------------------------===// 2392 2393/// isCheapEnoughToEvaluateUnconditionally - Return true if the specified 2394/// expression is cheap enough and side-effect-free enough to evaluate 2395/// unconditionally instead of conditionally. This is used to convert control 2396/// flow into selects in some cases. 2397static bool isCheapEnoughToEvaluateUnconditionally(const Expr *E, 2398 CodeGenFunction &CGF) { 2399 E = E->IgnoreParens(); 2400 2401 // Anything that is an integer or floating point constant is fine. 2402 if (E->isConstantInitializer(CGF.getContext(), false)) 2403 return true; 2404 2405 // Non-volatile automatic variables too, to get "cond ? X : Y" where 2406 // X and Y are local variables. 2407 if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(E)) 2408 if (const VarDecl *VD = dyn_cast<VarDecl>(DRE->getDecl())) 2409 if (VD->hasLocalStorage() && !(CGF.getContext() 2410 .getCanonicalType(VD->getType()) 2411 .isVolatileQualified())) 2412 return true; 2413 2414 return false; 2415} 2416 2417 2418Value *ScalarExprEmitter:: 2419VisitAbstractConditionalOperator(const AbstractConditionalOperator *E) { 2420 TestAndClearIgnoreResultAssign(); 2421 2422 // Bind the common expression if necessary. 2423 CodeGenFunction::OpaqueValueMapping binding(CGF, E); 2424 2425 Expr *condExpr = E->getCond(); 2426 Expr *lhsExpr = E->getTrueExpr(); 2427 Expr *rhsExpr = E->getFalseExpr(); 2428 2429 // If the condition constant folds and can be elided, try to avoid emitting 2430 // the condition and the dead arm. 2431 bool CondExprBool; 2432 if (CGF.ConstantFoldsToSimpleInteger(condExpr, CondExprBool)) { 2433 Expr *live = lhsExpr, *dead = rhsExpr; 2434 if (!CondExprBool) std::swap(live, dead); 2435 2436 // If the dead side doesn't have labels we need, and if the Live side isn't 2437 // the gnu missing ?: extension (which we could handle, but don't bother 2438 // to), just emit the Live part. 2439 if (!CGF.ContainsLabel(dead)) 2440 return Visit(live); 2441 } 2442 2443 // OpenCL: If the condition is a vector, we can treat this condition like 2444 // the select function. 2445 if (CGF.getContext().getLangOptions().OpenCL 2446 && condExpr->getType()->isVectorType()) { 2447 llvm::Value *CondV = CGF.EmitScalarExpr(condExpr); 2448 llvm::Value *LHS = Visit(lhsExpr); 2449 llvm::Value *RHS = Visit(rhsExpr); 2450 2451 const llvm::Type *condType = ConvertType(condExpr->getType()); 2452 const llvm::VectorType *vecTy = cast<llvm::VectorType>(condType); 2453 2454 unsigned numElem = vecTy->getNumElements(); 2455 const llvm::Type *elemType = vecTy->getElementType(); 2456 2457 std::vector<llvm::Constant*> Zvals; 2458 for (unsigned i = 0; i < numElem; ++i) 2459 Zvals.push_back(llvm::ConstantInt::get(elemType, 0)); 2460 2461 llvm::Value *zeroVec = llvm::ConstantVector::get(Zvals); 2462 llvm::Value *TestMSB = Builder.CreateICmpSLT(CondV, zeroVec); 2463 llvm::Value *tmp = Builder.CreateSExt(TestMSB, 2464 llvm::VectorType::get(elemType, 2465 numElem), 2466 "sext"); 2467 llvm::Value *tmp2 = Builder.CreateNot(tmp); 2468 2469 // Cast float to int to perform ANDs if necessary. 2470 llvm::Value *RHSTmp = RHS; 2471 llvm::Value *LHSTmp = LHS; 2472 bool wasCast = false; 2473 const llvm::VectorType *rhsVTy = cast<llvm::VectorType>(RHS->getType()); 2474 if (rhsVTy->getElementType()->isFloatTy()) { 2475 RHSTmp = Builder.CreateBitCast(RHS, tmp2->getType()); 2476 LHSTmp = Builder.CreateBitCast(LHS, tmp->getType()); 2477 wasCast = true; 2478 } 2479 2480 llvm::Value *tmp3 = Builder.CreateAnd(RHSTmp, tmp2); 2481 llvm::Value *tmp4 = Builder.CreateAnd(LHSTmp, tmp); 2482 llvm::Value *tmp5 = Builder.CreateOr(tmp3, tmp4, "cond"); 2483 if (wasCast) 2484 tmp5 = Builder.CreateBitCast(tmp5, RHS->getType()); 2485 2486 return tmp5; 2487 } 2488 2489 // If this is a really simple expression (like x ? 4 : 5), emit this as a 2490 // select instead of as control flow. We can only do this if it is cheap and 2491 // safe to evaluate the LHS and RHS unconditionally. 2492 if (isCheapEnoughToEvaluateUnconditionally(lhsExpr, CGF) && 2493 isCheapEnoughToEvaluateUnconditionally(rhsExpr, CGF)) { 2494 llvm::Value *CondV = CGF.EvaluateExprAsBool(condExpr); 2495 llvm::Value *LHS = Visit(lhsExpr); 2496 llvm::Value *RHS = Visit(rhsExpr); 2497 return Builder.CreateSelect(CondV, LHS, RHS, "cond"); 2498 } 2499 2500 llvm::BasicBlock *LHSBlock = CGF.createBasicBlock("cond.true"); 2501 llvm::BasicBlock *RHSBlock = CGF.createBasicBlock("cond.false"); 2502 llvm::BasicBlock *ContBlock = CGF.createBasicBlock("cond.end"); 2503 2504 CodeGenFunction::ConditionalEvaluation eval(CGF); 2505 CGF.EmitBranchOnBoolExpr(condExpr, LHSBlock, RHSBlock); 2506 2507 CGF.EmitBlock(LHSBlock); 2508 eval.begin(CGF); 2509 Value *LHS = Visit(lhsExpr); 2510 eval.end(CGF); 2511 2512 LHSBlock = Builder.GetInsertBlock(); 2513 Builder.CreateBr(ContBlock); 2514 2515 CGF.EmitBlock(RHSBlock); 2516 eval.begin(CGF); 2517 Value *RHS = Visit(rhsExpr); 2518 eval.end(CGF); 2519 2520 RHSBlock = Builder.GetInsertBlock(); 2521 CGF.EmitBlock(ContBlock); 2522 2523 // If the LHS or RHS is a throw expression, it will be legitimately null. 2524 if (!LHS) 2525 return RHS; 2526 if (!RHS) 2527 return LHS; 2528 2529 // Create a PHI node for the real part. 2530 llvm::PHINode *PN = Builder.CreatePHI(LHS->getType(), 2, "cond"); 2531 PN->addIncoming(LHS, LHSBlock); 2532 PN->addIncoming(RHS, RHSBlock); 2533 return PN; 2534} 2535 2536Value *ScalarExprEmitter::VisitChooseExpr(ChooseExpr *E) { 2537 return Visit(E->getChosenSubExpr(CGF.getContext())); 2538} 2539 2540Value *ScalarExprEmitter::VisitVAArgExpr(VAArgExpr *VE) { 2541 llvm::Value *ArgValue = CGF.EmitVAListRef(VE->getSubExpr()); 2542 llvm::Value *ArgPtr = CGF.EmitVAArg(ArgValue, VE->getType()); 2543 2544 // If EmitVAArg fails, we fall back to the LLVM instruction. 2545 if (!ArgPtr) 2546 return Builder.CreateVAArg(ArgValue, ConvertType(VE->getType())); 2547 2548 // FIXME Volatility. 2549 return Builder.CreateLoad(ArgPtr); 2550} 2551 2552Value *ScalarExprEmitter::VisitBlockExpr(const BlockExpr *block) { 2553 return CGF.EmitBlockLiteral(block); 2554} 2555 2556//===----------------------------------------------------------------------===// 2557// Entry Point into this File 2558//===----------------------------------------------------------------------===// 2559 2560/// EmitScalarExpr - Emit the computation of the specified expression of scalar 2561/// type, ignoring the result. 2562Value *CodeGenFunction::EmitScalarExpr(const Expr *E, bool IgnoreResultAssign) { 2563 assert(E && !hasAggregateLLVMType(E->getType()) && 2564 "Invalid scalar expression to emit"); 2565 2566 if (isa<CXXDefaultArgExpr>(E)) 2567 disableDebugInfo(); 2568 Value *V = ScalarExprEmitter(*this, IgnoreResultAssign) 2569 .Visit(const_cast<Expr*>(E)); 2570 if (isa<CXXDefaultArgExpr>(E)) 2571 enableDebugInfo(); 2572 return V; 2573} 2574 2575/// EmitScalarConversion - Emit a conversion from the specified type to the 2576/// specified destination type, both of which are LLVM scalar types. 2577Value *CodeGenFunction::EmitScalarConversion(Value *Src, QualType SrcTy, 2578 QualType DstTy) { 2579 assert(!hasAggregateLLVMType(SrcTy) && !hasAggregateLLVMType(DstTy) && 2580 "Invalid scalar expression to emit"); 2581 return ScalarExprEmitter(*this).EmitScalarConversion(Src, SrcTy, DstTy); 2582} 2583 2584/// EmitComplexToScalarConversion - Emit a conversion from the specified complex 2585/// type to the specified destination type, where the destination type is an 2586/// LLVM scalar type. 2587Value *CodeGenFunction::EmitComplexToScalarConversion(ComplexPairTy Src, 2588 QualType SrcTy, 2589 QualType DstTy) { 2590 assert(SrcTy->isAnyComplexType() && !hasAggregateLLVMType(DstTy) && 2591 "Invalid complex -> scalar conversion"); 2592 return ScalarExprEmitter(*this).EmitComplexToScalarConversion(Src, SrcTy, 2593 DstTy); 2594} 2595 2596 2597llvm::Value *CodeGenFunction:: 2598EmitScalarPrePostIncDec(const UnaryOperator *E, LValue LV, 2599 bool isInc, bool isPre) { 2600 return ScalarExprEmitter(*this).EmitScalarPrePostIncDec(E, LV, isInc, isPre); 2601} 2602 2603LValue CodeGenFunction::EmitObjCIsaExpr(const ObjCIsaExpr *E) { 2604 llvm::Value *V; 2605 // object->isa or (*object).isa 2606 // Generate code as for: *(Class*)object 2607 // build Class* type 2608 const llvm::Type *ClassPtrTy = ConvertType(E->getType()); 2609 2610 Expr *BaseExpr = E->getBase(); 2611 if (BaseExpr->isRValue()) { 2612 V = CreateTempAlloca(ClassPtrTy, "resval"); 2613 llvm::Value *Src = EmitScalarExpr(BaseExpr); 2614 Builder.CreateStore(Src, V); 2615 V = ScalarExprEmitter(*this).EmitLoadOfLValue( 2616 MakeAddrLValue(V, E->getType()), E->getType()); 2617 } else { 2618 if (E->isArrow()) 2619 V = ScalarExprEmitter(*this).EmitLoadOfLValue(BaseExpr); 2620 else 2621 V = EmitLValue(BaseExpr).getAddress(); 2622 } 2623 2624 // build Class* type 2625 ClassPtrTy = ClassPtrTy->getPointerTo(); 2626 V = Builder.CreateBitCast(V, ClassPtrTy); 2627 return MakeAddrLValue(V, E->getType()); 2628} 2629 2630 2631LValue CodeGenFunction::EmitCompoundAssignmentLValue( 2632 const CompoundAssignOperator *E) { 2633 ScalarExprEmitter Scalar(*this); 2634 Value *Result = 0; 2635 switch (E->getOpcode()) { 2636#define COMPOUND_OP(Op) \ 2637 case BO_##Op##Assign: \ 2638 return Scalar.EmitCompoundAssignLValue(E, &ScalarExprEmitter::Emit##Op, \ 2639 Result) 2640 COMPOUND_OP(Mul); 2641 COMPOUND_OP(Div); 2642 COMPOUND_OP(Rem); 2643 COMPOUND_OP(Add); 2644 COMPOUND_OP(Sub); 2645 COMPOUND_OP(Shl); 2646 COMPOUND_OP(Shr); 2647 COMPOUND_OP(And); 2648 COMPOUND_OP(Xor); 2649 COMPOUND_OP(Or); 2650#undef COMPOUND_OP 2651 2652 case BO_PtrMemD: 2653 case BO_PtrMemI: 2654 case BO_Mul: 2655 case BO_Div: 2656 case BO_Rem: 2657 case BO_Add: 2658 case BO_Sub: 2659 case BO_Shl: 2660 case BO_Shr: 2661 case BO_LT: 2662 case BO_GT: 2663 case BO_LE: 2664 case BO_GE: 2665 case BO_EQ: 2666 case BO_NE: 2667 case BO_And: 2668 case BO_Xor: 2669 case BO_Or: 2670 case BO_LAnd: 2671 case BO_LOr: 2672 case BO_Assign: 2673 case BO_Comma: 2674 assert(false && "Not valid compound assignment operators"); 2675 break; 2676 } 2677 2678 llvm_unreachable("Unhandled compound assignment operator"); 2679} 2680