CGExprScalar.cpp revision c2c90011a688c04a4e980282f08c267e081c4b00
1//===--- CGExprScalar.cpp - Emit LLVM Code for Scalar Exprs ---------------===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9// 10// This contains code to emit Expr nodes with scalar LLVM types as LLVM code. 11// 12//===----------------------------------------------------------------------===// 13 14#include "clang/Frontend/CodeGenOptions.h" 15#include "CodeGenFunction.h" 16#include "CGCXXABI.h" 17#include "CGObjCRuntime.h" 18#include "CodeGenModule.h" 19#include "CGDebugInfo.h" 20#include "clang/AST/ASTContext.h" 21#include "clang/AST/DeclObjC.h" 22#include "clang/AST/RecordLayout.h" 23#include "clang/AST/StmtVisitor.h" 24#include "clang/Basic/TargetInfo.h" 25#include "llvm/Constants.h" 26#include "llvm/Function.h" 27#include "llvm/GlobalVariable.h" 28#include "llvm/Intrinsics.h" 29#include "llvm/Module.h" 30#include "llvm/Support/CFG.h" 31#include "llvm/Target/TargetData.h" 32#include <cstdarg> 33 34using namespace clang; 35using namespace CodeGen; 36using llvm::Value; 37 38//===----------------------------------------------------------------------===// 39// Scalar Expression Emitter 40//===----------------------------------------------------------------------===// 41 42namespace { 43struct BinOpInfo { 44 Value *LHS; 45 Value *RHS; 46 QualType Ty; // Computation Type. 47 BinaryOperator::Opcode Opcode; // Opcode of BinOp to perform 48 const Expr *E; // Entire expr, for error unsupported. May not be binop. 49}; 50 51static bool MustVisitNullValue(const Expr *E) { 52 // If a null pointer expression's type is the C++0x nullptr_t, then 53 // it's not necessarily a simple constant and it must be evaluated 54 // for its potential side effects. 55 return E->getType()->isNullPtrType(); 56} 57 58class ScalarExprEmitter 59 : public StmtVisitor<ScalarExprEmitter, Value*> { 60 CodeGenFunction &CGF; 61 CGBuilderTy &Builder; 62 bool IgnoreResultAssign; 63 llvm::LLVMContext &VMContext; 64public: 65 66 ScalarExprEmitter(CodeGenFunction &cgf, bool ira=false) 67 : CGF(cgf), Builder(CGF.Builder), IgnoreResultAssign(ira), 68 VMContext(cgf.getLLVMContext()) { 69 } 70 71 //===--------------------------------------------------------------------===// 72 // Utilities 73 //===--------------------------------------------------------------------===// 74 75 bool TestAndClearIgnoreResultAssign() { 76 bool I = IgnoreResultAssign; 77 IgnoreResultAssign = false; 78 return I; 79 } 80 81 const llvm::Type *ConvertType(QualType T) { return CGF.ConvertType(T); } 82 LValue EmitLValue(const Expr *E) { return CGF.EmitLValue(E); } 83 LValue EmitCheckedLValue(const Expr *E) { return CGF.EmitCheckedLValue(E); } 84 85 Value *EmitLoadOfLValue(LValue LV, QualType T) { 86 return CGF.EmitLoadOfLValue(LV, T).getScalarVal(); 87 } 88 89 /// EmitLoadOfLValue - Given an expression with complex type that represents a 90 /// value l-value, this method emits the address of the l-value, then loads 91 /// and returns the result. 92 Value *EmitLoadOfLValue(const Expr *E) { 93 return EmitLoadOfLValue(EmitCheckedLValue(E), E->getType()); 94 } 95 96 /// EmitConversionToBool - Convert the specified expression value to a 97 /// boolean (i1) truth value. This is equivalent to "Val != 0". 98 Value *EmitConversionToBool(Value *Src, QualType DstTy); 99 100 /// EmitScalarConversion - Emit a conversion from the specified type to the 101 /// specified destination type, both of which are LLVM scalar types. 102 Value *EmitScalarConversion(Value *Src, QualType SrcTy, QualType DstTy); 103 104 /// EmitComplexToScalarConversion - Emit a conversion from the specified 105 /// complex type to the specified destination type, where the destination type 106 /// is an LLVM scalar type. 107 Value *EmitComplexToScalarConversion(CodeGenFunction::ComplexPairTy Src, 108 QualType SrcTy, QualType DstTy); 109 110 /// EmitNullValue - Emit a value that corresponds to null for the given type. 111 Value *EmitNullValue(QualType Ty); 112 113 /// EmitFloatToBoolConversion - Perform an FP to boolean conversion. 114 Value *EmitFloatToBoolConversion(Value *V) { 115 // Compare against 0.0 for fp scalars. 116 llvm::Value *Zero = llvm::Constant::getNullValue(V->getType()); 117 return Builder.CreateFCmpUNE(V, Zero, "tobool"); 118 } 119 120 /// EmitPointerToBoolConversion - Perform a pointer to boolean conversion. 121 Value *EmitPointerToBoolConversion(Value *V) { 122 Value *Zero = llvm::ConstantPointerNull::get( 123 cast<llvm::PointerType>(V->getType())); 124 return Builder.CreateICmpNE(V, Zero, "tobool"); 125 } 126 127 Value *EmitIntToBoolConversion(Value *V) { 128 // Because of the type rules of C, we often end up computing a 129 // logical value, then zero extending it to int, then wanting it 130 // as a logical value again. Optimize this common case. 131 if (llvm::ZExtInst *ZI = dyn_cast<llvm::ZExtInst>(V)) { 132 if (ZI->getOperand(0)->getType() == Builder.getInt1Ty()) { 133 Value *Result = ZI->getOperand(0); 134 // If there aren't any more uses, zap the instruction to save space. 135 // Note that there can be more uses, for example if this 136 // is the result of an assignment. 137 if (ZI->use_empty()) 138 ZI->eraseFromParent(); 139 return Result; 140 } 141 } 142 143 const llvm::IntegerType *Ty = cast<llvm::IntegerType>(V->getType()); 144 Value *Zero = llvm::ConstantInt::get(Ty, 0); 145 return Builder.CreateICmpNE(V, Zero, "tobool"); 146 } 147 148 //===--------------------------------------------------------------------===// 149 // Visitor Methods 150 //===--------------------------------------------------------------------===// 151 152 Value *Visit(Expr *E) { 153 return StmtVisitor<ScalarExprEmitter, Value*>::Visit(E); 154 } 155 156 Value *VisitStmt(Stmt *S) { 157 S->dump(CGF.getContext().getSourceManager()); 158 assert(0 && "Stmt can't have complex result type!"); 159 return 0; 160 } 161 Value *VisitExpr(Expr *S); 162 163 Value *VisitParenExpr(ParenExpr *PE) { 164 return Visit(PE->getSubExpr()); 165 } 166 167 // Leaves. 168 Value *VisitIntegerLiteral(const IntegerLiteral *E) { 169 return llvm::ConstantInt::get(VMContext, E->getValue()); 170 } 171 Value *VisitFloatingLiteral(const FloatingLiteral *E) { 172 return llvm::ConstantFP::get(VMContext, E->getValue()); 173 } 174 Value *VisitCharacterLiteral(const CharacterLiteral *E) { 175 return llvm::ConstantInt::get(ConvertType(E->getType()), E->getValue()); 176 } 177 Value *VisitCXXBoolLiteralExpr(const CXXBoolLiteralExpr *E) { 178 return llvm::ConstantInt::get(ConvertType(E->getType()), E->getValue()); 179 } 180 Value *VisitCXXScalarValueInitExpr(const CXXScalarValueInitExpr *E) { 181 return EmitNullValue(E->getType()); 182 } 183 Value *VisitGNUNullExpr(const GNUNullExpr *E) { 184 return EmitNullValue(E->getType()); 185 } 186 Value *VisitOffsetOfExpr(OffsetOfExpr *E); 187 Value *VisitSizeOfAlignOfExpr(const SizeOfAlignOfExpr *E); 188 Value *VisitAddrLabelExpr(const AddrLabelExpr *E) { 189 llvm::Value *V = CGF.GetAddrOfLabel(E->getLabel()); 190 return Builder.CreateBitCast(V, ConvertType(E->getType())); 191 } 192 193 Value *VisitSizeOfPackExpr(SizeOfPackExpr *E) { 194 return llvm::ConstantInt::get(ConvertType(E->getType()), 195 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 = llvm::ConstantInt::get(VMContext, 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 } 222 223 // Make sure we emit a debug reference to the global variable. 224 if (VarDecl *VD = dyn_cast<VarDecl>(E->getDecl())) { 225 if (!CGF.getContext().DeclMustBeEmitted(VD)) 226 CGF.EmitDeclRefExprDbgValue(E, C); 227 } else if (isa<EnumConstantDecl>(E->getDecl())) { 228 CGF.EmitDeclRefExprDbgValue(E, C); 229 } 230 231 return C; 232 } 233 Value *VisitObjCSelectorExpr(ObjCSelectorExpr *E) { 234 return CGF.EmitObjCSelectorExpr(E); 235 } 236 Value *VisitObjCProtocolExpr(ObjCProtocolExpr *E) { 237 return CGF.EmitObjCProtocolExpr(E); 238 } 239 Value *VisitObjCIvarRefExpr(ObjCIvarRefExpr *E) { 240 return EmitLoadOfLValue(E); 241 } 242 Value *VisitObjCPropertyRefExpr(ObjCPropertyRefExpr *E) { 243 assert(E->getObjectKind() == OK_Ordinary && 244 "reached property reference without lvalue-to-rvalue"); 245 return EmitLoadOfLValue(E); 246 } 247 Value *VisitObjCMessageExpr(ObjCMessageExpr *E) { 248 return CGF.EmitObjCMessageExpr(E).getScalarVal(); 249 } 250 251 Value *VisitObjCIsaExpr(ObjCIsaExpr *E) { 252 LValue LV = CGF.EmitObjCIsaExpr(E); 253 Value *V = CGF.EmitLoadOfLValue(LV, E->getType()).getScalarVal(); 254 return V; 255 } 256 257 Value *VisitArraySubscriptExpr(ArraySubscriptExpr *E); 258 Value *VisitShuffleVectorExpr(ShuffleVectorExpr *E); 259 Value *VisitMemberExpr(MemberExpr *E); 260 Value *VisitExtVectorElementExpr(Expr *E) { return EmitLoadOfLValue(E); } 261 Value *VisitCompoundLiteralExpr(CompoundLiteralExpr *E) { 262 return EmitLoadOfLValue(E); 263 } 264 265 Value *VisitInitListExpr(InitListExpr *E); 266 267 Value *VisitImplicitValueInitExpr(const ImplicitValueInitExpr *E) { 268 return CGF.CGM.EmitNullConstant(E->getType()); 269 } 270 Value *VisitCastExpr(CastExpr *E) { 271 // Make sure to evaluate VLA bounds now so that we have them for later. 272 if (E->getType()->isVariablyModifiedType()) 273 CGF.EmitVLASize(E->getType()); 274 275 return EmitCastExpr(E); 276 } 277 Value *EmitCastExpr(CastExpr *E); 278 279 Value *VisitCallExpr(const CallExpr *E) { 280 if (E->getCallReturnType()->isReferenceType()) 281 return EmitLoadOfLValue(E); 282 283 return CGF.EmitCallExpr(E).getScalarVal(); 284 } 285 286 Value *VisitStmtExpr(const StmtExpr *E); 287 288 Value *VisitBlockDeclRefExpr(const BlockDeclRefExpr *E); 289 290 // Unary Operators. 291 Value *VisitUnaryPostDec(const UnaryOperator *E) { 292 LValue LV = EmitLValue(E->getSubExpr()); 293 return EmitScalarPrePostIncDec(E, LV, false, false); 294 } 295 Value *VisitUnaryPostInc(const UnaryOperator *E) { 296 LValue LV = EmitLValue(E->getSubExpr()); 297 return EmitScalarPrePostIncDec(E, LV, true, false); 298 } 299 Value *VisitUnaryPreDec(const UnaryOperator *E) { 300 LValue LV = EmitLValue(E->getSubExpr()); 301 return EmitScalarPrePostIncDec(E, LV, false, true); 302 } 303 Value *VisitUnaryPreInc(const UnaryOperator *E) { 304 LValue LV = EmitLValue(E->getSubExpr()); 305 return EmitScalarPrePostIncDec(E, LV, true, true); 306 } 307 308 llvm::Value *EmitAddConsiderOverflowBehavior(const UnaryOperator *E, 309 llvm::Value *InVal, 310 llvm::Value *NextVal, 311 bool IsInc); 312 313 llvm::Value *EmitScalarPrePostIncDec(const UnaryOperator *E, LValue LV, 314 bool isInc, bool isPre); 315 316 317 Value *VisitUnaryAddrOf(const UnaryOperator *E) { 318 if (isa<MemberPointerType>(E->getType())) // never sugared 319 return CGF.CGM.getMemberPointerConstant(E); 320 321 return EmitLValue(E->getSubExpr()).getAddress(); 322 } 323 Value *VisitUnaryDeref(const UnaryOperator *E) { 324 if (E->getType()->isVoidType()) 325 return Visit(E->getSubExpr()); // the actual value should be unused 326 return EmitLoadOfLValue(E); 327 } 328 Value *VisitUnaryPlus(const UnaryOperator *E) { 329 // This differs from gcc, though, most likely due to a bug in gcc. 330 TestAndClearIgnoreResultAssign(); 331 return Visit(E->getSubExpr()); 332 } 333 Value *VisitUnaryMinus (const UnaryOperator *E); 334 Value *VisitUnaryNot (const UnaryOperator *E); 335 Value *VisitUnaryLNot (const UnaryOperator *E); 336 Value *VisitUnaryReal (const UnaryOperator *E); 337 Value *VisitUnaryImag (const UnaryOperator *E); 338 Value *VisitUnaryExtension(const UnaryOperator *E) { 339 return Visit(E->getSubExpr()); 340 } 341 342 // C++ 343 Value *VisitCXXDefaultArgExpr(CXXDefaultArgExpr *DAE) { 344 return Visit(DAE->getExpr()); 345 } 346 Value *VisitCXXThisExpr(CXXThisExpr *TE) { 347 return CGF.LoadCXXThis(); 348 } 349 350 Value *VisitExprWithCleanups(ExprWithCleanups *E) { 351 return CGF.EmitExprWithCleanups(E).getScalarVal(); 352 } 353 Value *VisitCXXNewExpr(const CXXNewExpr *E) { 354 return CGF.EmitCXXNewExpr(E); 355 } 356 Value *VisitCXXDeleteExpr(const CXXDeleteExpr *E) { 357 CGF.EmitCXXDeleteExpr(E); 358 return 0; 359 } 360 Value *VisitUnaryTypeTraitExpr(const UnaryTypeTraitExpr *E) { 361 return llvm::ConstantInt::get(Builder.getInt1Ty(), E->getValue()); 362 } 363 364 Value *VisitBinaryTypeTraitExpr(const BinaryTypeTraitExpr *E) { 365 return llvm::ConstantInt::get(ConvertType(E->getType()), E->getValue()); 366 } 367 368 Value *VisitCXXPseudoDestructorExpr(const CXXPseudoDestructorExpr *E) { 369 // C++ [expr.pseudo]p1: 370 // The result shall only be used as the operand for the function call 371 // operator (), and the result of such a call has type void. The only 372 // effect is the evaluation of the postfix-expression before the dot or 373 // arrow. 374 CGF.EmitScalarExpr(E->getBase()); 375 return 0; 376 } 377 378 Value *VisitCXXNullPtrLiteralExpr(const CXXNullPtrLiteralExpr *E) { 379 return EmitNullValue(E->getType()); 380 } 381 382 Value *VisitCXXThrowExpr(const CXXThrowExpr *E) { 383 CGF.EmitCXXThrowExpr(E); 384 return 0; 385 } 386 387 Value *VisitCXXNoexceptExpr(const CXXNoexceptExpr *E) { 388 return llvm::ConstantInt::get(Builder.getInt1Ty(), E->getValue()); 389 } 390 391 // Binary Operators. 392 Value *EmitMul(const BinOpInfo &Ops) { 393 if (Ops.Ty->hasSignedIntegerRepresentation()) { 394 switch (CGF.getContext().getLangOptions().getSignedOverflowBehavior()) { 395 case LangOptions::SOB_Undefined: 396 return Builder.CreateNSWMul(Ops.LHS, Ops.RHS, "mul"); 397 case LangOptions::SOB_Defined: 398 return Builder.CreateMul(Ops.LHS, Ops.RHS, "mul"); 399 case LangOptions::SOB_Trapping: 400 return EmitOverflowCheckedBinOp(Ops); 401 } 402 } 403 404 if (Ops.LHS->getType()->isFPOrFPVectorTy()) 405 return Builder.CreateFMul(Ops.LHS, Ops.RHS, "mul"); 406 return Builder.CreateMul(Ops.LHS, Ops.RHS, "mul"); 407 } 408 bool isTrapvOverflowBehavior() { 409 return CGF.getContext().getLangOptions().getSignedOverflowBehavior() 410 == LangOptions::SOB_Trapping; 411 } 412 /// Create a binary op that checks for overflow. 413 /// Currently only supports +, - and *. 414 Value *EmitOverflowCheckedBinOp(const BinOpInfo &Ops); 415 // Emit the overflow BB when -ftrapv option is activated. 416 void EmitOverflowBB(llvm::BasicBlock *overflowBB) { 417 Builder.SetInsertPoint(overflowBB); 418 llvm::Function *Trap = CGF.CGM.getIntrinsic(llvm::Intrinsic::trap); 419 Builder.CreateCall(Trap); 420 Builder.CreateUnreachable(); 421 } 422 // Check for undefined division and modulus behaviors. 423 void EmitUndefinedBehaviorIntegerDivAndRemCheck(const BinOpInfo &Ops, 424 llvm::Value *Zero,bool isDiv); 425 Value *EmitDiv(const BinOpInfo &Ops); 426 Value *EmitRem(const BinOpInfo &Ops); 427 Value *EmitAdd(const BinOpInfo &Ops); 428 Value *EmitSub(const BinOpInfo &Ops); 429 Value *EmitShl(const BinOpInfo &Ops); 430 Value *EmitShr(const BinOpInfo &Ops); 431 Value *EmitAnd(const BinOpInfo &Ops) { 432 return Builder.CreateAnd(Ops.LHS, Ops.RHS, "and"); 433 } 434 Value *EmitXor(const BinOpInfo &Ops) { 435 return Builder.CreateXor(Ops.LHS, Ops.RHS, "xor"); 436 } 437 Value *EmitOr (const BinOpInfo &Ops) { 438 return Builder.CreateOr(Ops.LHS, Ops.RHS, "or"); 439 } 440 441 BinOpInfo EmitBinOps(const BinaryOperator *E); 442 LValue EmitCompoundAssignLValue(const CompoundAssignOperator *E, 443 Value *(ScalarExprEmitter::*F)(const BinOpInfo &), 444 Value *&Result); 445 446 Value *EmitCompoundAssign(const CompoundAssignOperator *E, 447 Value *(ScalarExprEmitter::*F)(const BinOpInfo &)); 448 449 // Binary operators and binary compound assignment operators. 450#define HANDLEBINOP(OP) \ 451 Value *VisitBin ## OP(const BinaryOperator *E) { \ 452 return Emit ## OP(EmitBinOps(E)); \ 453 } \ 454 Value *VisitBin ## OP ## Assign(const CompoundAssignOperator *E) { \ 455 return EmitCompoundAssign(E, &ScalarExprEmitter::Emit ## OP); \ 456 } 457 HANDLEBINOP(Mul) 458 HANDLEBINOP(Div) 459 HANDLEBINOP(Rem) 460 HANDLEBINOP(Add) 461 HANDLEBINOP(Sub) 462 HANDLEBINOP(Shl) 463 HANDLEBINOP(Shr) 464 HANDLEBINOP(And) 465 HANDLEBINOP(Xor) 466 HANDLEBINOP(Or) 467#undef HANDLEBINOP 468 469 // Comparisons. 470 Value *EmitCompare(const BinaryOperator *E, unsigned UICmpOpc, 471 unsigned SICmpOpc, unsigned FCmpOpc); 472#define VISITCOMP(CODE, UI, SI, FP) \ 473 Value *VisitBin##CODE(const BinaryOperator *E) { \ 474 return EmitCompare(E, llvm::ICmpInst::UI, llvm::ICmpInst::SI, \ 475 llvm::FCmpInst::FP); } 476 VISITCOMP(LT, ICMP_ULT, ICMP_SLT, FCMP_OLT) 477 VISITCOMP(GT, ICMP_UGT, ICMP_SGT, FCMP_OGT) 478 VISITCOMP(LE, ICMP_ULE, ICMP_SLE, FCMP_OLE) 479 VISITCOMP(GE, ICMP_UGE, ICMP_SGE, FCMP_OGE) 480 VISITCOMP(EQ, ICMP_EQ , ICMP_EQ , FCMP_OEQ) 481 VISITCOMP(NE, ICMP_NE , ICMP_NE , FCMP_UNE) 482#undef VISITCOMP 483 484 Value *VisitBinAssign (const BinaryOperator *E); 485 486 Value *VisitBinLAnd (const BinaryOperator *E); 487 Value *VisitBinLOr (const BinaryOperator *E); 488 Value *VisitBinComma (const BinaryOperator *E); 489 490 Value *VisitBinPtrMemD(const Expr *E) { return EmitLoadOfLValue(E); } 491 Value *VisitBinPtrMemI(const Expr *E) { return EmitLoadOfLValue(E); } 492 493 // Other Operators. 494 Value *VisitBlockExpr(const BlockExpr *BE); 495 Value *VisitAbstractConditionalOperator(const AbstractConditionalOperator *); 496 Value *VisitChooseExpr(ChooseExpr *CE); 497 Value *VisitVAArgExpr(VAArgExpr *VE); 498 Value *VisitObjCStringLiteral(const ObjCStringLiteral *E) { 499 return CGF.EmitObjCStringLiteral(E); 500 } 501}; 502} // end anonymous namespace. 503 504//===----------------------------------------------------------------------===// 505// Utilities 506//===----------------------------------------------------------------------===// 507 508/// EmitConversionToBool - Convert the specified expression value to a 509/// boolean (i1) truth value. This is equivalent to "Val != 0". 510Value *ScalarExprEmitter::EmitConversionToBool(Value *Src, QualType SrcType) { 511 assert(SrcType.isCanonical() && "EmitScalarConversion strips typedefs"); 512 513 if (SrcType->isRealFloatingType()) 514 return EmitFloatToBoolConversion(Src); 515 516 if (const MemberPointerType *MPT = dyn_cast<MemberPointerType>(SrcType)) 517 return CGF.CGM.getCXXABI().EmitMemberPointerIsNotNull(CGF, Src, MPT); 518 519 assert((SrcType->isIntegerType() || isa<llvm::PointerType>(Src->getType())) && 520 "Unknown scalar type to convert"); 521 522 if (isa<llvm::IntegerType>(Src->getType())) 523 return EmitIntToBoolConversion(Src); 524 525 assert(isa<llvm::PointerType>(Src->getType())); 526 return EmitPointerToBoolConversion(Src); 527} 528 529/// EmitScalarConversion - Emit a conversion from the specified type to the 530/// specified destination type, both of which are LLVM scalar types. 531Value *ScalarExprEmitter::EmitScalarConversion(Value *Src, QualType SrcType, 532 QualType DstType) { 533 SrcType = CGF.getContext().getCanonicalType(SrcType); 534 DstType = CGF.getContext().getCanonicalType(DstType); 535 if (SrcType == DstType) return Src; 536 537 if (DstType->isVoidType()) return 0; 538 539 // Handle conversions to bool first, they are special: comparisons against 0. 540 if (DstType->isBooleanType()) 541 return EmitConversionToBool(Src, SrcType); 542 543 const llvm::Type *DstTy = ConvertType(DstType); 544 545 // Ignore conversions like int -> uint. 546 if (Src->getType() == DstTy) 547 return Src; 548 549 // Handle pointer conversions next: pointers can only be converted to/from 550 // other pointers and integers. Check for pointer types in terms of LLVM, as 551 // some native types (like Obj-C id) may map to a pointer type. 552 if (isa<llvm::PointerType>(DstTy)) { 553 // The source value may be an integer, or a pointer. 554 if (isa<llvm::PointerType>(Src->getType())) 555 return Builder.CreateBitCast(Src, DstTy, "conv"); 556 557 assert(SrcType->isIntegerType() && "Not ptr->ptr or int->ptr conversion?"); 558 // First, convert to the correct width so that we control the kind of 559 // extension. 560 const llvm::Type *MiddleTy = CGF.IntPtrTy; 561 bool InputSigned = SrcType->isSignedIntegerType(); 562 llvm::Value* IntResult = 563 Builder.CreateIntCast(Src, MiddleTy, InputSigned, "conv"); 564 // Then, cast to pointer. 565 return Builder.CreateIntToPtr(IntResult, DstTy, "conv"); 566 } 567 568 if (isa<llvm::PointerType>(Src->getType())) { 569 // Must be an ptr to int cast. 570 assert(isa<llvm::IntegerType>(DstTy) && "not ptr->int?"); 571 return Builder.CreatePtrToInt(Src, DstTy, "conv"); 572 } 573 574 // A scalar can be splatted to an extended vector of the same element type 575 if (DstType->isExtVectorType() && !SrcType->isVectorType()) { 576 // Cast the scalar to element type 577 QualType EltTy = DstType->getAs<ExtVectorType>()->getElementType(); 578 llvm::Value *Elt = EmitScalarConversion(Src, SrcType, EltTy); 579 580 // Insert the element in element zero of an undef vector 581 llvm::Value *UnV = llvm::UndefValue::get(DstTy); 582 llvm::Value *Idx = llvm::ConstantInt::get(CGF.Int32Ty, 0); 583 UnV = Builder.CreateInsertElement(UnV, Elt, Idx, "tmp"); 584 585 // Splat the element across to all elements 586 llvm::SmallVector<llvm::Constant*, 16> Args; 587 unsigned NumElements = cast<llvm::VectorType>(DstTy)->getNumElements(); 588 for (unsigned i = 0; i != NumElements; ++i) 589 Args.push_back(llvm::ConstantInt::get(CGF.Int32Ty, 0)); 590 591 llvm::Constant *Mask = llvm::ConstantVector::get(Args); 592 llvm::Value *Yay = Builder.CreateShuffleVector(UnV, UnV, Mask, "splat"); 593 return Yay; 594 } 595 596 // Allow bitcast from vector to integer/fp of the same size. 597 if (isa<llvm::VectorType>(Src->getType()) || 598 isa<llvm::VectorType>(DstTy)) 599 return Builder.CreateBitCast(Src, DstTy, "conv"); 600 601 // Finally, we have the arithmetic types: real int/float. 602 if (isa<llvm::IntegerType>(Src->getType())) { 603 bool InputSigned = SrcType->isSignedIntegerType(); 604 if (isa<llvm::IntegerType>(DstTy)) 605 return Builder.CreateIntCast(Src, DstTy, InputSigned, "conv"); 606 else if (InputSigned) 607 return Builder.CreateSIToFP(Src, DstTy, "conv"); 608 else 609 return Builder.CreateUIToFP(Src, DstTy, "conv"); 610 } 611 612 assert(Src->getType()->isFloatingPointTy() && "Unknown real conversion"); 613 if (isa<llvm::IntegerType>(DstTy)) { 614 if (DstType->isSignedIntegerType()) 615 return Builder.CreateFPToSI(Src, DstTy, "conv"); 616 else 617 return Builder.CreateFPToUI(Src, DstTy, "conv"); 618 } 619 620 assert(DstTy->isFloatingPointTy() && "Unknown real conversion"); 621 if (DstTy->getTypeID() < Src->getType()->getTypeID()) 622 return Builder.CreateFPTrunc(Src, DstTy, "conv"); 623 else 624 return Builder.CreateFPExt(Src, DstTy, "conv"); 625} 626 627/// EmitComplexToScalarConversion - Emit a conversion from the specified complex 628/// type to the specified destination type, where the destination type is an 629/// LLVM scalar type. 630Value *ScalarExprEmitter:: 631EmitComplexToScalarConversion(CodeGenFunction::ComplexPairTy Src, 632 QualType SrcTy, QualType DstTy) { 633 // Get the source element type. 634 SrcTy = SrcTy->getAs<ComplexType>()->getElementType(); 635 636 // Handle conversions to bool first, they are special: comparisons against 0. 637 if (DstTy->isBooleanType()) { 638 // Complex != 0 -> (Real != 0) | (Imag != 0) 639 Src.first = EmitScalarConversion(Src.first, SrcTy, DstTy); 640 Src.second = EmitScalarConversion(Src.second, SrcTy, DstTy); 641 return Builder.CreateOr(Src.first, Src.second, "tobool"); 642 } 643 644 // C99 6.3.1.7p2: "When a value of complex type is converted to a real type, 645 // the imaginary part of the complex value is discarded and the value of the 646 // real part is converted according to the conversion rules for the 647 // corresponding real type. 648 return EmitScalarConversion(Src.first, SrcTy, DstTy); 649} 650 651Value *ScalarExprEmitter::EmitNullValue(QualType Ty) { 652 if (const MemberPointerType *MPT = Ty->getAs<MemberPointerType>()) 653 return CGF.CGM.getCXXABI().EmitNullMemberPointer(MPT); 654 655 return llvm::Constant::getNullValue(ConvertType(Ty)); 656} 657 658//===----------------------------------------------------------------------===// 659// Visitor Methods 660//===----------------------------------------------------------------------===// 661 662Value *ScalarExprEmitter::VisitExpr(Expr *E) { 663 CGF.ErrorUnsupported(E, "scalar expression"); 664 if (E->getType()->isVoidType()) 665 return 0; 666 return llvm::UndefValue::get(CGF.ConvertType(E->getType())); 667} 668 669Value *ScalarExprEmitter::VisitShuffleVectorExpr(ShuffleVectorExpr *E) { 670 // Vector Mask Case 671 if (E->getNumSubExprs() == 2 || 672 (E->getNumSubExprs() == 3 && E->getExpr(2)->getType()->isVectorType())) { 673 Value *LHS = CGF.EmitScalarExpr(E->getExpr(0)); 674 Value *RHS = CGF.EmitScalarExpr(E->getExpr(1)); 675 Value *Mask; 676 677 const llvm::VectorType *LTy = cast<llvm::VectorType>(LHS->getType()); 678 unsigned LHSElts = LTy->getNumElements(); 679 680 if (E->getNumSubExprs() == 3) { 681 Mask = CGF.EmitScalarExpr(E->getExpr(2)); 682 683 // Shuffle LHS & RHS into one input vector. 684 llvm::SmallVector<llvm::Constant*, 32> concat; 685 for (unsigned i = 0; i != LHSElts; ++i) { 686 concat.push_back(llvm::ConstantInt::get(CGF.Int32Ty, 2*i)); 687 concat.push_back(llvm::ConstantInt::get(CGF.Int32Ty, 2*i+1)); 688 } 689 690 Value* CV = llvm::ConstantVector::get(concat); 691 LHS = Builder.CreateShuffleVector(LHS, RHS, CV, "concat"); 692 LHSElts *= 2; 693 } else { 694 Mask = RHS; 695 } 696 697 const llvm::VectorType *MTy = cast<llvm::VectorType>(Mask->getType()); 698 llvm::Constant* EltMask; 699 700 // Treat vec3 like vec4. 701 if ((LHSElts == 6) && (E->getNumSubExprs() == 3)) 702 EltMask = llvm::ConstantInt::get(MTy->getElementType(), 703 (1 << llvm::Log2_32(LHSElts+2))-1); 704 else if ((LHSElts == 3) && (E->getNumSubExprs() == 2)) 705 EltMask = llvm::ConstantInt::get(MTy->getElementType(), 706 (1 << llvm::Log2_32(LHSElts+1))-1); 707 else 708 EltMask = llvm::ConstantInt::get(MTy->getElementType(), 709 (1 << llvm::Log2_32(LHSElts))-1); 710 711 // Mask off the high bits of each shuffle index. 712 llvm::SmallVector<llvm::Constant *, 32> MaskV; 713 for (unsigned i = 0, e = MTy->getNumElements(); i != e; ++i) 714 MaskV.push_back(EltMask); 715 716 Value* MaskBits = llvm::ConstantVector::get(MaskV); 717 Mask = Builder.CreateAnd(Mask, MaskBits, "mask"); 718 719 // newv = undef 720 // mask = mask & maskbits 721 // for each elt 722 // n = extract mask i 723 // x = extract val n 724 // newv = insert newv, x, i 725 const llvm::VectorType *RTy = llvm::VectorType::get(LTy->getElementType(), 726 MTy->getNumElements()); 727 Value* NewV = llvm::UndefValue::get(RTy); 728 for (unsigned i = 0, e = MTy->getNumElements(); i != e; ++i) { 729 Value *Indx = llvm::ConstantInt::get(CGF.Int32Ty, i); 730 Indx = Builder.CreateExtractElement(Mask, Indx, "shuf_idx"); 731 Indx = Builder.CreateZExt(Indx, CGF.Int32Ty, "idx_zext"); 732 733 // Handle vec3 special since the index will be off by one for the RHS. 734 if ((LHSElts == 6) && (E->getNumSubExprs() == 3)) { 735 Value *cmpIndx, *newIndx; 736 cmpIndx = Builder.CreateICmpUGT(Indx, 737 llvm::ConstantInt::get(CGF.Int32Ty, 3), 738 "cmp_shuf_idx"); 739 newIndx = Builder.CreateSub(Indx, llvm::ConstantInt::get(CGF.Int32Ty,1), 740 "shuf_idx_adj"); 741 Indx = Builder.CreateSelect(cmpIndx, newIndx, Indx, "sel_shuf_idx"); 742 } 743 Value *VExt = Builder.CreateExtractElement(LHS, Indx, "shuf_elt"); 744 NewV = Builder.CreateInsertElement(NewV, VExt, Indx, "shuf_ins"); 745 } 746 return NewV; 747 } 748 749 Value* V1 = CGF.EmitScalarExpr(E->getExpr(0)); 750 Value* V2 = CGF.EmitScalarExpr(E->getExpr(1)); 751 752 // Handle vec3 special since the index will be off by one for the RHS. 753 llvm::SmallVector<llvm::Constant*, 32> indices; 754 for (unsigned i = 2; i < E->getNumSubExprs(); i++) { 755 llvm::Constant *C = cast<llvm::Constant>(CGF.EmitScalarExpr(E->getExpr(i))); 756 const llvm::VectorType *VTy = cast<llvm::VectorType>(V1->getType()); 757 if (VTy->getNumElements() == 3) { 758 if (llvm::ConstantInt *CI = dyn_cast<llvm::ConstantInt>(C)) { 759 uint64_t cVal = CI->getZExtValue(); 760 if (cVal > 3) { 761 C = llvm::ConstantInt::get(C->getType(), cVal-1); 762 } 763 } 764 } 765 indices.push_back(C); 766 } 767 768 Value *SV = llvm::ConstantVector::get(indices); 769 return Builder.CreateShuffleVector(V1, V2, SV, "shuffle"); 770} 771Value *ScalarExprEmitter::VisitMemberExpr(MemberExpr *E) { 772 Expr::EvalResult Result; 773 if (E->Evaluate(Result, CGF.getContext()) && Result.Val.isInt()) { 774 if (E->isArrow()) 775 CGF.EmitScalarExpr(E->getBase()); 776 else 777 EmitLValue(E->getBase()); 778 return llvm::ConstantInt::get(VMContext, Result.Val.getInt()); 779 } 780 781 // Emit debug info for aggregate now, if it was delayed to reduce 782 // debug info size. 783 CGDebugInfo *DI = CGF.getDebugInfo(); 784 if (DI && CGF.CGM.getCodeGenOpts().LimitDebugInfo) { 785 QualType PQTy = E->getBase()->IgnoreParenImpCasts()->getType(); 786 if (const PointerType * PTy = dyn_cast<PointerType>(PQTy)) 787 if (FieldDecl *M = dyn_cast<FieldDecl>(E->getMemberDecl())) 788 DI->getOrCreateRecordType(PTy->getPointeeType(), 789 M->getParent()->getLocation()); 790 } 791 return EmitLoadOfLValue(E); 792} 793 794Value *ScalarExprEmitter::VisitArraySubscriptExpr(ArraySubscriptExpr *E) { 795 TestAndClearIgnoreResultAssign(); 796 797 // Emit subscript expressions in rvalue context's. For most cases, this just 798 // loads the lvalue formed by the subscript expr. However, we have to be 799 // careful, because the base of a vector subscript is occasionally an rvalue, 800 // so we can't get it as an lvalue. 801 if (!E->getBase()->getType()->isVectorType()) 802 return EmitLoadOfLValue(E); 803 804 // Handle the vector case. The base must be a vector, the index must be an 805 // integer value. 806 Value *Base = Visit(E->getBase()); 807 Value *Idx = Visit(E->getIdx()); 808 bool IdxSigned = E->getIdx()->getType()->isSignedIntegerType(); 809 Idx = Builder.CreateIntCast(Idx, CGF.Int32Ty, IdxSigned, "vecidxcast"); 810 return Builder.CreateExtractElement(Base, Idx, "vecext"); 811} 812 813static llvm::Constant *getMaskElt(llvm::ShuffleVectorInst *SVI, unsigned Idx, 814 unsigned Off, const llvm::Type *I32Ty) { 815 int MV = SVI->getMaskValue(Idx); 816 if (MV == -1) 817 return llvm::UndefValue::get(I32Ty); 818 return llvm::ConstantInt::get(I32Ty, Off+MV); 819} 820 821Value *ScalarExprEmitter::VisitInitListExpr(InitListExpr *E) { 822 bool Ignore = TestAndClearIgnoreResultAssign(); 823 (void)Ignore; 824 assert (Ignore == false && "init list ignored"); 825 unsigned NumInitElements = E->getNumInits(); 826 827 if (E->hadArrayRangeDesignator()) 828 CGF.ErrorUnsupported(E, "GNU array range designator extension"); 829 830 const llvm::VectorType *VType = 831 dyn_cast<llvm::VectorType>(ConvertType(E->getType())); 832 833 // We have a scalar in braces. Just use the first element. 834 if (!VType) 835 return Visit(E->getInit(0)); 836 837 unsigned ResElts = VType->getNumElements(); 838 839 // Loop over initializers collecting the Value for each, and remembering 840 // whether the source was swizzle (ExtVectorElementExpr). This will allow 841 // us to fold the shuffle for the swizzle into the shuffle for the vector 842 // initializer, since LLVM optimizers generally do not want to touch 843 // shuffles. 844 unsigned CurIdx = 0; 845 bool VIsUndefShuffle = false; 846 llvm::Value *V = llvm::UndefValue::get(VType); 847 for (unsigned i = 0; i != NumInitElements; ++i) { 848 Expr *IE = E->getInit(i); 849 Value *Init = Visit(IE); 850 llvm::SmallVector<llvm::Constant*, 16> Args; 851 852 const llvm::VectorType *VVT = dyn_cast<llvm::VectorType>(Init->getType()); 853 854 // Handle scalar elements. If the scalar initializer is actually one 855 // element of a different vector of the same width, use shuffle instead of 856 // extract+insert. 857 if (!VVT) { 858 if (isa<ExtVectorElementExpr>(IE)) { 859 llvm::ExtractElementInst *EI = cast<llvm::ExtractElementInst>(Init); 860 861 if (EI->getVectorOperandType()->getNumElements() == ResElts) { 862 llvm::ConstantInt *C = cast<llvm::ConstantInt>(EI->getIndexOperand()); 863 Value *LHS = 0, *RHS = 0; 864 if (CurIdx == 0) { 865 // insert into undef -> shuffle (src, undef) 866 Args.push_back(C); 867 for (unsigned j = 1; j != ResElts; ++j) 868 Args.push_back(llvm::UndefValue::get(CGF.Int32Ty)); 869 870 LHS = EI->getVectorOperand(); 871 RHS = V; 872 VIsUndefShuffle = true; 873 } else if (VIsUndefShuffle) { 874 // insert into undefshuffle && size match -> shuffle (v, src) 875 llvm::ShuffleVectorInst *SVV = cast<llvm::ShuffleVectorInst>(V); 876 for (unsigned j = 0; j != CurIdx; ++j) 877 Args.push_back(getMaskElt(SVV, j, 0, CGF.Int32Ty)); 878 Args.push_back(llvm::ConstantInt::get(CGF.Int32Ty, 879 ResElts + C->getZExtValue())); 880 for (unsigned j = CurIdx + 1; j != ResElts; ++j) 881 Args.push_back(llvm::UndefValue::get(CGF.Int32Ty)); 882 883 LHS = cast<llvm::ShuffleVectorInst>(V)->getOperand(0); 884 RHS = EI->getVectorOperand(); 885 VIsUndefShuffle = false; 886 } 887 if (!Args.empty()) { 888 llvm::Constant *Mask = llvm::ConstantVector::get(Args); 889 V = Builder.CreateShuffleVector(LHS, RHS, Mask); 890 ++CurIdx; 891 continue; 892 } 893 } 894 } 895 Value *Idx = llvm::ConstantInt::get(CGF.Int32Ty, CurIdx); 896 V = Builder.CreateInsertElement(V, Init, Idx, "vecinit"); 897 VIsUndefShuffle = false; 898 ++CurIdx; 899 continue; 900 } 901 902 unsigned InitElts = VVT->getNumElements(); 903 904 // If the initializer is an ExtVecEltExpr (a swizzle), and the swizzle's 905 // input is the same width as the vector being constructed, generate an 906 // optimized shuffle of the swizzle input into the result. 907 unsigned Offset = (CurIdx == 0) ? 0 : ResElts; 908 if (isa<ExtVectorElementExpr>(IE)) { 909 llvm::ShuffleVectorInst *SVI = cast<llvm::ShuffleVectorInst>(Init); 910 Value *SVOp = SVI->getOperand(0); 911 const llvm::VectorType *OpTy = cast<llvm::VectorType>(SVOp->getType()); 912 913 if (OpTy->getNumElements() == ResElts) { 914 for (unsigned j = 0; j != CurIdx; ++j) { 915 // If the current vector initializer is a shuffle with undef, merge 916 // this shuffle directly into it. 917 if (VIsUndefShuffle) { 918 Args.push_back(getMaskElt(cast<llvm::ShuffleVectorInst>(V), j, 0, 919 CGF.Int32Ty)); 920 } else { 921 Args.push_back(llvm::ConstantInt::get(CGF.Int32Ty, j)); 922 } 923 } 924 for (unsigned j = 0, je = InitElts; j != je; ++j) 925 Args.push_back(getMaskElt(SVI, j, Offset, CGF.Int32Ty)); 926 for (unsigned j = CurIdx + InitElts; j != ResElts; ++j) 927 Args.push_back(llvm::UndefValue::get(CGF.Int32Ty)); 928 929 if (VIsUndefShuffle) 930 V = cast<llvm::ShuffleVectorInst>(V)->getOperand(0); 931 932 Init = SVOp; 933 } 934 } 935 936 // Extend init to result vector length, and then shuffle its contribution 937 // to the vector initializer into V. 938 if (Args.empty()) { 939 for (unsigned j = 0; j != InitElts; ++j) 940 Args.push_back(llvm::ConstantInt::get(CGF.Int32Ty, j)); 941 for (unsigned j = InitElts; j != ResElts; ++j) 942 Args.push_back(llvm::UndefValue::get(CGF.Int32Ty)); 943 llvm::Constant *Mask = llvm::ConstantVector::get(Args); 944 Init = Builder.CreateShuffleVector(Init, llvm::UndefValue::get(VVT), 945 Mask, "vext"); 946 947 Args.clear(); 948 for (unsigned j = 0; j != CurIdx; ++j) 949 Args.push_back(llvm::ConstantInt::get(CGF.Int32Ty, j)); 950 for (unsigned j = 0; j != InitElts; ++j) 951 Args.push_back(llvm::ConstantInt::get(CGF.Int32Ty, j+Offset)); 952 for (unsigned j = CurIdx + InitElts; j != ResElts; ++j) 953 Args.push_back(llvm::UndefValue::get(CGF.Int32Ty)); 954 } 955 956 // If V is undef, make sure it ends up on the RHS of the shuffle to aid 957 // merging subsequent shuffles into this one. 958 if (CurIdx == 0) 959 std::swap(V, Init); 960 llvm::Constant *Mask = llvm::ConstantVector::get(Args); 961 V = Builder.CreateShuffleVector(V, Init, Mask, "vecinit"); 962 VIsUndefShuffle = isa<llvm::UndefValue>(Init); 963 CurIdx += InitElts; 964 } 965 966 // FIXME: evaluate codegen vs. shuffling against constant null vector. 967 // Emit remaining default initializers. 968 const llvm::Type *EltTy = VType->getElementType(); 969 970 // Emit remaining default initializers 971 for (/* Do not initialize i*/; CurIdx < ResElts; ++CurIdx) { 972 Value *Idx = llvm::ConstantInt::get(CGF.Int32Ty, CurIdx); 973 llvm::Value *Init = llvm::Constant::getNullValue(EltTy); 974 V = Builder.CreateInsertElement(V, Init, Idx, "vecinit"); 975 } 976 return V; 977} 978 979static bool ShouldNullCheckClassCastValue(const CastExpr *CE) { 980 const Expr *E = CE->getSubExpr(); 981 982 if (CE->getCastKind() == CK_UncheckedDerivedToBase) 983 return false; 984 985 if (isa<CXXThisExpr>(E)) { 986 // We always assume that 'this' is never null. 987 return false; 988 } 989 990 if (const ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(CE)) { 991 // And that glvalue casts are never null. 992 if (ICE->getValueKind() != VK_RValue) 993 return false; 994 } 995 996 return true; 997} 998 999// VisitCastExpr - Emit code for an explicit or implicit cast. Implicit casts 1000// have to handle a more broad range of conversions than explicit casts, as they 1001// handle things like function to ptr-to-function decay etc. 1002Value *ScalarExprEmitter::EmitCastExpr(CastExpr *CE) { 1003 Expr *E = CE->getSubExpr(); 1004 QualType DestTy = CE->getType(); 1005 CastKind Kind = CE->getCastKind(); 1006 1007 if (!DestTy->isVoidType()) 1008 TestAndClearIgnoreResultAssign(); 1009 1010 // Since almost all cast kinds apply to scalars, this switch doesn't have 1011 // a default case, so the compiler will warn on a missing case. The cases 1012 // are in the same order as in the CastKind enum. 1013 switch (Kind) { 1014 case CK_Dependent: llvm_unreachable("dependent cast kind in IR gen!"); 1015 1016 case CK_LValueBitCast: 1017 case CK_ObjCObjectLValueCast: { 1018 Value *V = EmitLValue(E).getAddress(); 1019 V = Builder.CreateBitCast(V, 1020 ConvertType(CGF.getContext().getPointerType(DestTy))); 1021 return EmitLoadOfLValue(CGF.MakeAddrLValue(V, DestTy), DestTy); 1022 } 1023 1024 case CK_AnyPointerToObjCPointerCast: 1025 case CK_AnyPointerToBlockPointerCast: 1026 case CK_BitCast: { 1027 Value *Src = Visit(const_cast<Expr*>(E)); 1028 return Builder.CreateBitCast(Src, ConvertType(DestTy)); 1029 } 1030 case CK_NoOp: 1031 case CK_UserDefinedConversion: 1032 return Visit(const_cast<Expr*>(E)); 1033 1034 case CK_BaseToDerived: { 1035 const CXXRecordDecl *DerivedClassDecl = 1036 DestTy->getCXXRecordDeclForPointerType(); 1037 1038 return CGF.GetAddressOfDerivedClass(Visit(E), DerivedClassDecl, 1039 CE->path_begin(), CE->path_end(), 1040 ShouldNullCheckClassCastValue(CE)); 1041 } 1042 case CK_UncheckedDerivedToBase: 1043 case CK_DerivedToBase: { 1044 const RecordType *DerivedClassTy = 1045 E->getType()->getAs<PointerType>()->getPointeeType()->getAs<RecordType>(); 1046 CXXRecordDecl *DerivedClassDecl = 1047 cast<CXXRecordDecl>(DerivedClassTy->getDecl()); 1048 1049 return CGF.GetAddressOfBaseClass(Visit(E), DerivedClassDecl, 1050 CE->path_begin(), CE->path_end(), 1051 ShouldNullCheckClassCastValue(CE)); 1052 } 1053 case CK_Dynamic: { 1054 Value *V = Visit(const_cast<Expr*>(E)); 1055 const CXXDynamicCastExpr *DCE = cast<CXXDynamicCastExpr>(CE); 1056 return CGF.EmitDynamicCast(V, DCE); 1057 } 1058 1059 case CK_ArrayToPointerDecay: { 1060 assert(E->getType()->isArrayType() && 1061 "Array to pointer decay must have array source type!"); 1062 1063 Value *V = EmitLValue(E).getAddress(); // Bitfields can't be arrays. 1064 1065 // Note that VLA pointers are always decayed, so we don't need to do 1066 // anything here. 1067 if (!E->getType()->isVariableArrayType()) { 1068 assert(isa<llvm::PointerType>(V->getType()) && "Expected pointer"); 1069 assert(isa<llvm::ArrayType>(cast<llvm::PointerType>(V->getType()) 1070 ->getElementType()) && 1071 "Expected pointer to array"); 1072 V = Builder.CreateStructGEP(V, 0, "arraydecay"); 1073 } 1074 1075 return V; 1076 } 1077 case CK_FunctionToPointerDecay: 1078 return EmitLValue(E).getAddress(); 1079 1080 case CK_NullToPointer: 1081 if (MustVisitNullValue(E)) 1082 (void) Visit(E); 1083 1084 return llvm::ConstantPointerNull::get( 1085 cast<llvm::PointerType>(ConvertType(DestTy))); 1086 1087 case CK_NullToMemberPointer: { 1088 if (MustVisitNullValue(E)) 1089 (void) Visit(E); 1090 1091 const MemberPointerType *MPT = CE->getType()->getAs<MemberPointerType>(); 1092 return CGF.CGM.getCXXABI().EmitNullMemberPointer(MPT); 1093 } 1094 1095 case CK_BaseToDerivedMemberPointer: 1096 case CK_DerivedToBaseMemberPointer: { 1097 Value *Src = Visit(E); 1098 1099 // Note that the AST doesn't distinguish between checked and 1100 // unchecked member pointer conversions, so we always have to 1101 // implement checked conversions here. This is inefficient when 1102 // actual control flow may be required in order to perform the 1103 // check, which it is for data member pointers (but not member 1104 // function pointers on Itanium and ARM). 1105 return CGF.CGM.getCXXABI().EmitMemberPointerConversion(CGF, CE, Src); 1106 } 1107 1108 case CK_FloatingRealToComplex: 1109 case CK_FloatingComplexCast: 1110 case CK_IntegralRealToComplex: 1111 case CK_IntegralComplexCast: 1112 case CK_IntegralComplexToFloatingComplex: 1113 case CK_FloatingComplexToIntegralComplex: 1114 case CK_ConstructorConversion: 1115 case CK_ToUnion: 1116 llvm_unreachable("scalar cast to non-scalar value"); 1117 break; 1118 1119 case CK_GetObjCProperty: { 1120 assert(CGF.getContext().hasSameUnqualifiedType(E->getType(), DestTy)); 1121 assert(E->isGLValue() && E->getObjectKind() == OK_ObjCProperty && 1122 "CK_GetObjCProperty for non-lvalue or non-ObjCProperty"); 1123 RValue RV = CGF.EmitLoadOfLValue(CGF.EmitLValue(E), E->getType()); 1124 return RV.getScalarVal(); 1125 } 1126 1127 case CK_LValueToRValue: 1128 assert(CGF.getContext().hasSameUnqualifiedType(E->getType(), DestTy)); 1129 assert(E->isGLValue() && "lvalue-to-rvalue applied to r-value!"); 1130 return Visit(const_cast<Expr*>(E)); 1131 1132 case CK_IntegralToPointer: { 1133 Value *Src = Visit(const_cast<Expr*>(E)); 1134 1135 // First, convert to the correct width so that we control the kind of 1136 // extension. 1137 const llvm::Type *MiddleTy = CGF.IntPtrTy; 1138 bool InputSigned = E->getType()->isSignedIntegerType(); 1139 llvm::Value* IntResult = 1140 Builder.CreateIntCast(Src, MiddleTy, InputSigned, "conv"); 1141 1142 return Builder.CreateIntToPtr(IntResult, ConvertType(DestTy)); 1143 } 1144 case CK_PointerToIntegral: { 1145 Value *Src = Visit(const_cast<Expr*>(E)); 1146 1147 // Handle conversion to bool correctly. 1148 if (DestTy->isBooleanType()) 1149 return EmitScalarConversion(Src, E->getType(), DestTy); 1150 1151 return Builder.CreatePtrToInt(Src, ConvertType(DestTy)); 1152 } 1153 case CK_ToVoid: { 1154 CGF.EmitIgnoredExpr(E); 1155 return 0; 1156 } 1157 case CK_VectorSplat: { 1158 const llvm::Type *DstTy = ConvertType(DestTy); 1159 Value *Elt = Visit(const_cast<Expr*>(E)); 1160 1161 // Insert the element in element zero of an undef vector 1162 llvm::Value *UnV = llvm::UndefValue::get(DstTy); 1163 llvm::Value *Idx = llvm::ConstantInt::get(CGF.Int32Ty, 0); 1164 UnV = Builder.CreateInsertElement(UnV, Elt, Idx, "tmp"); 1165 1166 // Splat the element across to all elements 1167 llvm::SmallVector<llvm::Constant*, 16> Args; 1168 unsigned NumElements = cast<llvm::VectorType>(DstTy)->getNumElements(); 1169 llvm::Constant *Zero = llvm::ConstantInt::get(CGF.Int32Ty, 0); 1170 for (unsigned i = 0; i < NumElements; i++) 1171 Args.push_back(Zero); 1172 1173 llvm::Constant *Mask = llvm::ConstantVector::get(Args); 1174 llvm::Value *Yay = Builder.CreateShuffleVector(UnV, UnV, Mask, "splat"); 1175 return Yay; 1176 } 1177 1178 case CK_IntegralCast: 1179 case CK_IntegralToFloating: 1180 case CK_FloatingToIntegral: 1181 case CK_FloatingCast: 1182 return EmitScalarConversion(Visit(E), E->getType(), DestTy); 1183 1184 case CK_IntegralToBoolean: 1185 return EmitIntToBoolConversion(Visit(E)); 1186 case CK_PointerToBoolean: 1187 return EmitPointerToBoolConversion(Visit(E)); 1188 case CK_FloatingToBoolean: 1189 return EmitFloatToBoolConversion(Visit(E)); 1190 case CK_MemberPointerToBoolean: { 1191 llvm::Value *MemPtr = Visit(E); 1192 const MemberPointerType *MPT = E->getType()->getAs<MemberPointerType>(); 1193 return CGF.CGM.getCXXABI().EmitMemberPointerIsNotNull(CGF, MemPtr, MPT); 1194 } 1195 1196 case CK_FloatingComplexToReal: 1197 case CK_IntegralComplexToReal: 1198 return CGF.EmitComplexExpr(E, false, true).first; 1199 1200 case CK_FloatingComplexToBoolean: 1201 case CK_IntegralComplexToBoolean: { 1202 CodeGenFunction::ComplexPairTy V = CGF.EmitComplexExpr(E); 1203 1204 // TODO: kill this function off, inline appropriate case here 1205 return EmitComplexToScalarConversion(V, E->getType(), DestTy); 1206 } 1207 1208 } 1209 1210 llvm_unreachable("unknown scalar cast"); 1211 return 0; 1212} 1213 1214Value *ScalarExprEmitter::VisitStmtExpr(const StmtExpr *E) { 1215 CodeGenFunction::StmtExprEvaluation eval(CGF); 1216 return CGF.EmitCompoundStmt(*E->getSubStmt(), !E->getType()->isVoidType()) 1217 .getScalarVal(); 1218} 1219 1220Value *ScalarExprEmitter::VisitBlockDeclRefExpr(const BlockDeclRefExpr *E) { 1221 llvm::Value *V = CGF.GetAddrOfBlockDecl(E); 1222 if (E->getType().isObjCGCWeak()) 1223 return CGF.CGM.getObjCRuntime().EmitObjCWeakRead(CGF, V); 1224 return CGF.EmitLoadOfScalar(V, false, 0, E->getType()); 1225} 1226 1227//===----------------------------------------------------------------------===// 1228// Unary Operators 1229//===----------------------------------------------------------------------===// 1230 1231llvm::Value *ScalarExprEmitter:: 1232EmitAddConsiderOverflowBehavior(const UnaryOperator *E, 1233 llvm::Value *InVal, 1234 llvm::Value *NextVal, bool IsInc) { 1235 switch (CGF.getContext().getLangOptions().getSignedOverflowBehavior()) { 1236 case LangOptions::SOB_Undefined: 1237 return Builder.CreateNSWAdd(InVal, NextVal, IsInc ? "inc" : "dec"); 1238 break; 1239 case LangOptions::SOB_Defined: 1240 return Builder.CreateAdd(InVal, NextVal, IsInc ? "inc" : "dec"); 1241 break; 1242 case LangOptions::SOB_Trapping: 1243 BinOpInfo BinOp; 1244 BinOp.LHS = InVal; 1245 BinOp.RHS = NextVal; 1246 BinOp.Ty = E->getType(); 1247 BinOp.Opcode = BO_Add; 1248 BinOp.E = E; 1249 return EmitOverflowCheckedBinOp(BinOp); 1250 break; 1251 } 1252 assert(false && "Unknown SignedOverflowBehaviorTy"); 1253 return 0; 1254} 1255 1256llvm::Value * 1257ScalarExprEmitter::EmitScalarPrePostIncDec(const UnaryOperator *E, LValue LV, 1258 bool isInc, bool isPre) { 1259 1260 QualType type = E->getSubExpr()->getType(); 1261 llvm::Value *value = EmitLoadOfLValue(LV, type); 1262 llvm::Value *input = value; 1263 1264 int amount = (isInc ? 1 : -1); 1265 1266 // Special case of integer increment that we have to check first: bool++. 1267 // Due to promotion rules, we get: 1268 // bool++ -> bool = bool + 1 1269 // -> bool = (int)bool + 1 1270 // -> bool = ((int)bool + 1 != 0) 1271 // An interesting aspect of this is that increment is always true. 1272 // Decrement does not have this property. 1273 if (isInc && type->isBooleanType()) { 1274 value = Builder.getTrue(); 1275 1276 // Most common case by far: integer increment. 1277 } else if (type->isIntegerType()) { 1278 1279 llvm::Value *amt = llvm::ConstantInt::get(value->getType(), amount); 1280 1281 if (type->isSignedIntegerType()) 1282 value = EmitAddConsiderOverflowBehavior(E, value, amt, isInc); 1283 1284 // Unsigned integer inc is always two's complement. 1285 else 1286 value = Builder.CreateAdd(value, amt, isInc ? "inc" : "dec"); 1287 1288 // Next most common: pointer increment. 1289 } else if (const PointerType *ptr = type->getAs<PointerType>()) { 1290 QualType type = ptr->getPointeeType(); 1291 1292 // VLA types don't have constant size. 1293 if (type->isVariableArrayType()) { 1294 llvm::Value *vlaSize = 1295 CGF.GetVLASize(CGF.getContext().getAsVariableArrayType(type)); 1296 value = CGF.EmitCastToVoidPtr(value); 1297 if (!isInc) vlaSize = Builder.CreateNSWNeg(vlaSize, "vla.negsize"); 1298 value = Builder.CreateInBoundsGEP(value, vlaSize, "vla.inc"); 1299 value = Builder.CreateBitCast(value, input->getType()); 1300 1301 // Arithmetic on function pointers (!) is just +-1. 1302 } else if (type->isFunctionType()) { 1303 llvm::Value *amt = llvm::ConstantInt::get(CGF.Int32Ty, amount); 1304 1305 value = CGF.EmitCastToVoidPtr(value); 1306 value = Builder.CreateInBoundsGEP(value, amt, "incdec.funcptr"); 1307 value = Builder.CreateBitCast(value, input->getType()); 1308 1309 // For everything else, we can just do a simple increment. 1310 } else { 1311 llvm::Value *amt = llvm::ConstantInt::get(CGF.Int32Ty, amount); 1312 value = Builder.CreateInBoundsGEP(value, amt, "incdec.ptr"); 1313 } 1314 1315 // Vector increment/decrement. 1316 } else if (type->isVectorType()) { 1317 if (type->hasIntegerRepresentation()) { 1318 llvm::Value *amt = llvm::ConstantInt::get(value->getType(), amount); 1319 1320 if (type->hasSignedIntegerRepresentation()) 1321 value = EmitAddConsiderOverflowBehavior(E, value, amt, isInc); 1322 else 1323 value = Builder.CreateAdd(value, amt, isInc ? "inc" : "dec"); 1324 } else { 1325 value = Builder.CreateFAdd( 1326 value, 1327 llvm::ConstantFP::get(value->getType(), amount), 1328 isInc ? "inc" : "dec"); 1329 } 1330 1331 // Floating point. 1332 } else if (type->isRealFloatingType()) { 1333 // Add the inc/dec to the real part. 1334 llvm::Value *amt; 1335 if (value->getType()->isFloatTy()) 1336 amt = llvm::ConstantFP::get(VMContext, 1337 llvm::APFloat(static_cast<float>(amount))); 1338 else if (value->getType()->isDoubleTy()) 1339 amt = llvm::ConstantFP::get(VMContext, 1340 llvm::APFloat(static_cast<double>(amount))); 1341 else { 1342 llvm::APFloat F(static_cast<float>(amount)); 1343 bool ignored; 1344 F.convert(CGF.Target.getLongDoubleFormat(), llvm::APFloat::rmTowardZero, 1345 &ignored); 1346 amt = llvm::ConstantFP::get(VMContext, F); 1347 } 1348 value = Builder.CreateFAdd(value, amt, isInc ? "inc" : "dec"); 1349 1350 // Objective-C pointer types. 1351 } else { 1352 const ObjCObjectPointerType *OPT = type->castAs<ObjCObjectPointerType>(); 1353 value = CGF.EmitCastToVoidPtr(value); 1354 1355 CharUnits size = CGF.getContext().getTypeSizeInChars(OPT->getObjectType()); 1356 if (!isInc) size = -size; 1357 llvm::Value *sizeValue = 1358 llvm::ConstantInt::get(CGF.SizeTy, size.getQuantity()); 1359 1360 value = Builder.CreateInBoundsGEP(value, sizeValue, "incdec.objptr"); 1361 value = Builder.CreateBitCast(value, input->getType()); 1362 } 1363 1364 // Store the updated result through the lvalue. 1365 if (LV.isBitField()) 1366 CGF.EmitStoreThroughBitfieldLValue(RValue::get(value), LV, type, &value); 1367 else 1368 CGF.EmitStoreThroughLValue(RValue::get(value), LV, type); 1369 1370 // If this is a postinc, return the value read from memory, otherwise use the 1371 // updated value. 1372 return isPre ? value : input; 1373} 1374 1375 1376 1377Value *ScalarExprEmitter::VisitUnaryMinus(const UnaryOperator *E) { 1378 TestAndClearIgnoreResultAssign(); 1379 // Emit unary minus with EmitSub so we handle overflow cases etc. 1380 BinOpInfo BinOp; 1381 BinOp.RHS = Visit(E->getSubExpr()); 1382 1383 if (BinOp.RHS->getType()->isFPOrFPVectorTy()) 1384 BinOp.LHS = llvm::ConstantFP::getZeroValueForNegation(BinOp.RHS->getType()); 1385 else 1386 BinOp.LHS = llvm::Constant::getNullValue(BinOp.RHS->getType()); 1387 BinOp.Ty = E->getType(); 1388 BinOp.Opcode = BO_Sub; 1389 BinOp.E = E; 1390 return EmitSub(BinOp); 1391} 1392 1393Value *ScalarExprEmitter::VisitUnaryNot(const UnaryOperator *E) { 1394 TestAndClearIgnoreResultAssign(); 1395 Value *Op = Visit(E->getSubExpr()); 1396 return Builder.CreateNot(Op, "neg"); 1397} 1398 1399Value *ScalarExprEmitter::VisitUnaryLNot(const UnaryOperator *E) { 1400 // Compare operand to zero. 1401 Value *BoolVal = CGF.EvaluateExprAsBool(E->getSubExpr()); 1402 1403 // Invert value. 1404 // TODO: Could dynamically modify easy computations here. For example, if 1405 // the operand is an icmp ne, turn into icmp eq. 1406 BoolVal = Builder.CreateNot(BoolVal, "lnot"); 1407 1408 // ZExt result to the expr type. 1409 return Builder.CreateZExt(BoolVal, ConvertType(E->getType()), "lnot.ext"); 1410} 1411 1412Value *ScalarExprEmitter::VisitOffsetOfExpr(OffsetOfExpr *E) { 1413 // Try folding the offsetof to a constant. 1414 Expr::EvalResult EvalResult; 1415 if (E->Evaluate(EvalResult, CGF.getContext())) 1416 return llvm::ConstantInt::get(VMContext, EvalResult.Val.getInt()); 1417 1418 // Loop over the components of the offsetof to compute the value. 1419 unsigned n = E->getNumComponents(); 1420 const llvm::Type* ResultType = ConvertType(E->getType()); 1421 llvm::Value* Result = llvm::Constant::getNullValue(ResultType); 1422 QualType CurrentType = E->getTypeSourceInfo()->getType(); 1423 for (unsigned i = 0; i != n; ++i) { 1424 OffsetOfExpr::OffsetOfNode ON = E->getComponent(i); 1425 llvm::Value *Offset = 0; 1426 switch (ON.getKind()) { 1427 case OffsetOfExpr::OffsetOfNode::Array: { 1428 // Compute the index 1429 Expr *IdxExpr = E->getIndexExpr(ON.getArrayExprIndex()); 1430 llvm::Value* Idx = CGF.EmitScalarExpr(IdxExpr); 1431 bool IdxSigned = IdxExpr->getType()->isSignedIntegerType(); 1432 Idx = Builder.CreateIntCast(Idx, ResultType, IdxSigned, "conv"); 1433 1434 // Save the element type 1435 CurrentType = 1436 CGF.getContext().getAsArrayType(CurrentType)->getElementType(); 1437 1438 // Compute the element size 1439 llvm::Value* ElemSize = llvm::ConstantInt::get(ResultType, 1440 CGF.getContext().getTypeSizeInChars(CurrentType).getQuantity()); 1441 1442 // Multiply out to compute the result 1443 Offset = Builder.CreateMul(Idx, ElemSize); 1444 break; 1445 } 1446 1447 case OffsetOfExpr::OffsetOfNode::Field: { 1448 FieldDecl *MemberDecl = ON.getField(); 1449 RecordDecl *RD = CurrentType->getAs<RecordType>()->getDecl(); 1450 const ASTRecordLayout &RL = CGF.getContext().getASTRecordLayout(RD); 1451 1452 // Compute the index of the field in its parent. 1453 unsigned i = 0; 1454 // FIXME: It would be nice if we didn't have to loop here! 1455 for (RecordDecl::field_iterator Field = RD->field_begin(), 1456 FieldEnd = RD->field_end(); 1457 Field != FieldEnd; (void)++Field, ++i) { 1458 if (*Field == MemberDecl) 1459 break; 1460 } 1461 assert(i < RL.getFieldCount() && "offsetof field in wrong type"); 1462 1463 // Compute the offset to the field 1464 int64_t OffsetInt = RL.getFieldOffset(i) / 1465 CGF.getContext().getCharWidth(); 1466 Offset = llvm::ConstantInt::get(ResultType, OffsetInt); 1467 1468 // Save the element type. 1469 CurrentType = MemberDecl->getType(); 1470 break; 1471 } 1472 1473 case OffsetOfExpr::OffsetOfNode::Identifier: 1474 llvm_unreachable("dependent __builtin_offsetof"); 1475 1476 case OffsetOfExpr::OffsetOfNode::Base: { 1477 if (ON.getBase()->isVirtual()) { 1478 CGF.ErrorUnsupported(E, "virtual base in offsetof"); 1479 continue; 1480 } 1481 1482 RecordDecl *RD = CurrentType->getAs<RecordType>()->getDecl(); 1483 const ASTRecordLayout &RL = CGF.getContext().getASTRecordLayout(RD); 1484 1485 // Save the element type. 1486 CurrentType = ON.getBase()->getType(); 1487 1488 // Compute the offset to the base. 1489 const RecordType *BaseRT = CurrentType->getAs<RecordType>(); 1490 CXXRecordDecl *BaseRD = cast<CXXRecordDecl>(BaseRT->getDecl()); 1491 int64_t OffsetInt = RL.getBaseClassOffsetInBits(BaseRD) / 1492 CGF.getContext().getCharWidth(); 1493 Offset = llvm::ConstantInt::get(ResultType, OffsetInt); 1494 break; 1495 } 1496 } 1497 Result = Builder.CreateAdd(Result, Offset); 1498 } 1499 return Result; 1500} 1501 1502/// VisitSizeOfAlignOfExpr - Return the size or alignment of the type of 1503/// argument of the sizeof expression as an integer. 1504Value * 1505ScalarExprEmitter::VisitSizeOfAlignOfExpr(const SizeOfAlignOfExpr *E) { 1506 QualType TypeToSize = E->getTypeOfArgument(); 1507 if (E->isSizeOf()) { 1508 if (const VariableArrayType *VAT = 1509 CGF.getContext().getAsVariableArrayType(TypeToSize)) { 1510 if (E->isArgumentType()) { 1511 // sizeof(type) - make sure to emit the VLA size. 1512 CGF.EmitVLASize(TypeToSize); 1513 } else { 1514 // C99 6.5.3.4p2: If the argument is an expression of type 1515 // VLA, it is evaluated. 1516 CGF.EmitIgnoredExpr(E->getArgumentExpr()); 1517 } 1518 1519 return CGF.GetVLASize(VAT); 1520 } 1521 } 1522 1523 // If this isn't sizeof(vla), the result must be constant; use the constant 1524 // folding logic so we don't have to duplicate it here. 1525 Expr::EvalResult Result; 1526 E->Evaluate(Result, CGF.getContext()); 1527 return llvm::ConstantInt::get(VMContext, Result.Val.getInt()); 1528} 1529 1530Value *ScalarExprEmitter::VisitUnaryReal(const UnaryOperator *E) { 1531 Expr *Op = E->getSubExpr(); 1532 if (Op->getType()->isAnyComplexType()) { 1533 // If it's an l-value, load through the appropriate subobject l-value. 1534 // Note that we have to ask E because Op might be an l-value that 1535 // this won't work for, e.g. an Obj-C property. 1536 if (E->isGLValue()) 1537 return CGF.EmitLoadOfLValue(CGF.EmitLValue(E), E->getType()) 1538 .getScalarVal(); 1539 1540 // Otherwise, calculate and project. 1541 return CGF.EmitComplexExpr(Op, false, true).first; 1542 } 1543 1544 return Visit(Op); 1545} 1546 1547Value *ScalarExprEmitter::VisitUnaryImag(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 (Op->isGLValue()) 1554 return CGF.EmitLoadOfLValue(CGF.EmitLValue(E), E->getType()) 1555 .getScalarVal(); 1556 1557 // Otherwise, calculate and project. 1558 return CGF.EmitComplexExpr(Op, true, false).second; 1559 } 1560 1561 // __imag on a scalar returns zero. Emit the subexpr to ensure side 1562 // effects are evaluated, but not the actual value. 1563 CGF.EmitScalarExpr(Op, true); 1564 return llvm::Constant::getNullValue(ConvertType(E->getType())); 1565} 1566 1567//===----------------------------------------------------------------------===// 1568// Binary Operators 1569//===----------------------------------------------------------------------===// 1570 1571BinOpInfo ScalarExprEmitter::EmitBinOps(const BinaryOperator *E) { 1572 TestAndClearIgnoreResultAssign(); 1573 BinOpInfo Result; 1574 Result.LHS = Visit(E->getLHS()); 1575 Result.RHS = Visit(E->getRHS()); 1576 Result.Ty = E->getType(); 1577 Result.Opcode = E->getOpcode(); 1578 Result.E = E; 1579 return Result; 1580} 1581 1582LValue ScalarExprEmitter::EmitCompoundAssignLValue( 1583 const CompoundAssignOperator *E, 1584 Value *(ScalarExprEmitter::*Func)(const BinOpInfo &), 1585 Value *&Result) { 1586 QualType LHSTy = E->getLHS()->getType(); 1587 BinOpInfo OpInfo; 1588 1589 if (E->getComputationResultType()->isAnyComplexType()) { 1590 // This needs to go through the complex expression emitter, but it's a tad 1591 // complicated to do that... I'm leaving it out for now. (Note that we do 1592 // actually need the imaginary part of the RHS for multiplication and 1593 // division.) 1594 CGF.ErrorUnsupported(E, "complex compound assignment"); 1595 Result = llvm::UndefValue::get(CGF.ConvertType(E->getType())); 1596 return LValue(); 1597 } 1598 1599 // Emit the RHS first. __block variables need to have the rhs evaluated 1600 // first, plus this should improve codegen a little. 1601 OpInfo.RHS = Visit(E->getRHS()); 1602 OpInfo.Ty = E->getComputationResultType(); 1603 OpInfo.Opcode = E->getOpcode(); 1604 OpInfo.E = E; 1605 // Load/convert the LHS. 1606 LValue LHSLV = EmitCheckedLValue(E->getLHS()); 1607 OpInfo.LHS = EmitLoadOfLValue(LHSLV, LHSTy); 1608 OpInfo.LHS = EmitScalarConversion(OpInfo.LHS, LHSTy, 1609 E->getComputationLHSType()); 1610 1611 // Expand the binary operator. 1612 Result = (this->*Func)(OpInfo); 1613 1614 // Convert the result back to the LHS type. 1615 Result = EmitScalarConversion(Result, E->getComputationResultType(), LHSTy); 1616 1617 // Store the result value into the LHS lvalue. Bit-fields are handled 1618 // specially because the result is altered by the store, i.e., [C99 6.5.16p1] 1619 // 'An assignment expression has the value of the left operand after the 1620 // assignment...'. 1621 if (LHSLV.isBitField()) 1622 CGF.EmitStoreThroughBitfieldLValue(RValue::get(Result), LHSLV, LHSTy, 1623 &Result); 1624 else 1625 CGF.EmitStoreThroughLValue(RValue::get(Result), LHSLV, LHSTy); 1626 1627 return LHSLV; 1628} 1629 1630Value *ScalarExprEmitter::EmitCompoundAssign(const CompoundAssignOperator *E, 1631 Value *(ScalarExprEmitter::*Func)(const BinOpInfo &)) { 1632 bool Ignore = TestAndClearIgnoreResultAssign(); 1633 Value *RHS; 1634 LValue LHS = EmitCompoundAssignLValue(E, Func, RHS); 1635 1636 // If the result is clearly ignored, return now. 1637 if (Ignore) 1638 return 0; 1639 1640 // The result of an assignment in C is the assigned r-value. 1641 if (!CGF.getContext().getLangOptions().CPlusPlus) 1642 return RHS; 1643 1644 // Objective-C property assignment never reloads the value following a store. 1645 if (LHS.isPropertyRef()) 1646 return RHS; 1647 1648 // If the lvalue is non-volatile, return the computed value of the assignment. 1649 if (!LHS.isVolatileQualified()) 1650 return RHS; 1651 1652 // Otherwise, reload the value. 1653 return EmitLoadOfLValue(LHS, E->getType()); 1654} 1655 1656void ScalarExprEmitter::EmitUndefinedBehaviorIntegerDivAndRemCheck( 1657 const BinOpInfo &Ops, 1658 llvm::Value *Zero, bool isDiv) { 1659 llvm::BasicBlock *overflowBB = CGF.createBasicBlock("overflow", CGF.CurFn); 1660 llvm::BasicBlock *contBB = 1661 CGF.createBasicBlock(isDiv ? "div.cont" : "rem.cont", CGF.CurFn); 1662 1663 const llvm::IntegerType *Ty = cast<llvm::IntegerType>(Zero->getType()); 1664 1665 if (Ops.Ty->hasSignedIntegerRepresentation()) { 1666 llvm::Value *IntMin = 1667 llvm::ConstantInt::get(VMContext, 1668 llvm::APInt::getSignedMinValue(Ty->getBitWidth())); 1669 llvm::Value *NegOne = llvm::ConstantInt::get(Ty, -1ULL); 1670 1671 llvm::Value *Cond1 = Builder.CreateICmpEQ(Ops.RHS, Zero); 1672 llvm::Value *LHSCmp = Builder.CreateICmpEQ(Ops.LHS, IntMin); 1673 llvm::Value *RHSCmp = Builder.CreateICmpEQ(Ops.RHS, NegOne); 1674 llvm::Value *Cond2 = Builder.CreateAnd(LHSCmp, RHSCmp, "and"); 1675 Builder.CreateCondBr(Builder.CreateOr(Cond1, Cond2, "or"), 1676 overflowBB, contBB); 1677 } else { 1678 CGF.Builder.CreateCondBr(Builder.CreateICmpEQ(Ops.RHS, Zero), 1679 overflowBB, contBB); 1680 } 1681 EmitOverflowBB(overflowBB); 1682 Builder.SetInsertPoint(contBB); 1683} 1684 1685Value *ScalarExprEmitter::EmitDiv(const BinOpInfo &Ops) { 1686 if (isTrapvOverflowBehavior()) { 1687 llvm::Value *Zero = llvm::Constant::getNullValue(ConvertType(Ops.Ty)); 1688 1689 if (Ops.Ty->isIntegerType()) 1690 EmitUndefinedBehaviorIntegerDivAndRemCheck(Ops, Zero, true); 1691 else if (Ops.Ty->isRealFloatingType()) { 1692 llvm::BasicBlock *overflowBB = CGF.createBasicBlock("overflow", 1693 CGF.CurFn); 1694 llvm::BasicBlock *DivCont = CGF.createBasicBlock("div.cont", CGF.CurFn); 1695 CGF.Builder.CreateCondBr(Builder.CreateFCmpOEQ(Ops.RHS, Zero), 1696 overflowBB, DivCont); 1697 EmitOverflowBB(overflowBB); 1698 Builder.SetInsertPoint(DivCont); 1699 } 1700 } 1701 if (Ops.LHS->getType()->isFPOrFPVectorTy()) 1702 return Builder.CreateFDiv(Ops.LHS, Ops.RHS, "div"); 1703 else if (Ops.Ty->hasUnsignedIntegerRepresentation()) 1704 return Builder.CreateUDiv(Ops.LHS, Ops.RHS, "div"); 1705 else 1706 return Builder.CreateSDiv(Ops.LHS, Ops.RHS, "div"); 1707} 1708 1709Value *ScalarExprEmitter::EmitRem(const BinOpInfo &Ops) { 1710 // Rem in C can't be a floating point type: C99 6.5.5p2. 1711 if (isTrapvOverflowBehavior()) { 1712 llvm::Value *Zero = llvm::Constant::getNullValue(ConvertType(Ops.Ty)); 1713 1714 if (Ops.Ty->isIntegerType()) 1715 EmitUndefinedBehaviorIntegerDivAndRemCheck(Ops, Zero, false); 1716 } 1717 1718 if (Ops.Ty->isUnsignedIntegerType()) 1719 return Builder.CreateURem(Ops.LHS, Ops.RHS, "rem"); 1720 else 1721 return Builder.CreateSRem(Ops.LHS, Ops.RHS, "rem"); 1722} 1723 1724Value *ScalarExprEmitter::EmitOverflowCheckedBinOp(const BinOpInfo &Ops) { 1725 unsigned IID; 1726 unsigned OpID = 0; 1727 1728 switch (Ops.Opcode) { 1729 case BO_Add: 1730 case BO_AddAssign: 1731 OpID = 1; 1732 IID = llvm::Intrinsic::sadd_with_overflow; 1733 break; 1734 case BO_Sub: 1735 case BO_SubAssign: 1736 OpID = 2; 1737 IID = llvm::Intrinsic::ssub_with_overflow; 1738 break; 1739 case BO_Mul: 1740 case BO_MulAssign: 1741 OpID = 3; 1742 IID = llvm::Intrinsic::smul_with_overflow; 1743 break; 1744 default: 1745 assert(false && "Unsupported operation for overflow detection"); 1746 IID = 0; 1747 } 1748 OpID <<= 1; 1749 OpID |= 1; 1750 1751 const llvm::Type *opTy = CGF.CGM.getTypes().ConvertType(Ops.Ty); 1752 1753 llvm::Function *intrinsic = CGF.CGM.getIntrinsic(IID, &opTy, 1); 1754 1755 Value *resultAndOverflow = Builder.CreateCall2(intrinsic, Ops.LHS, Ops.RHS); 1756 Value *result = Builder.CreateExtractValue(resultAndOverflow, 0); 1757 Value *overflow = Builder.CreateExtractValue(resultAndOverflow, 1); 1758 1759 // Branch in case of overflow. 1760 llvm::BasicBlock *initialBB = Builder.GetInsertBlock(); 1761 llvm::BasicBlock *overflowBB = CGF.createBasicBlock("overflow", CGF.CurFn); 1762 llvm::BasicBlock *continueBB = CGF.createBasicBlock("nooverflow", CGF.CurFn); 1763 1764 Builder.CreateCondBr(overflow, overflowBB, continueBB); 1765 1766 // Handle overflow with llvm.trap. 1767 const std::string *handlerName = 1768 &CGF.getContext().getLangOptions().OverflowHandler; 1769 if (handlerName->empty()) { 1770 EmitOverflowBB(overflowBB); 1771 Builder.SetInsertPoint(continueBB); 1772 return result; 1773 } 1774 1775 // If an overflow handler is set, then we want to call it and then use its 1776 // result, if it returns. 1777 Builder.SetInsertPoint(overflowBB); 1778 1779 // Get the overflow handler. 1780 const llvm::Type *Int8Ty = llvm::Type::getInt8Ty(VMContext); 1781 std::vector<const llvm::Type*> argTypes; 1782 argTypes.push_back(CGF.Int64Ty); argTypes.push_back(CGF.Int64Ty); 1783 argTypes.push_back(Int8Ty); argTypes.push_back(Int8Ty); 1784 llvm::FunctionType *handlerTy = 1785 llvm::FunctionType::get(CGF.Int64Ty, argTypes, true); 1786 llvm::Value *handler = CGF.CGM.CreateRuntimeFunction(handlerTy, *handlerName); 1787 1788 // Sign extend the args to 64-bit, so that we can use the same handler for 1789 // all types of overflow. 1790 llvm::Value *lhs = Builder.CreateSExt(Ops.LHS, CGF.Int64Ty); 1791 llvm::Value *rhs = Builder.CreateSExt(Ops.RHS, CGF.Int64Ty); 1792 1793 // Call the handler with the two arguments, the operation, and the size of 1794 // the result. 1795 llvm::Value *handlerResult = Builder.CreateCall4(handler, lhs, rhs, 1796 Builder.getInt8(OpID), 1797 Builder.getInt8(cast<llvm::IntegerType>(opTy)->getBitWidth())); 1798 1799 // Truncate the result back to the desired size. 1800 handlerResult = Builder.CreateTrunc(handlerResult, opTy); 1801 Builder.CreateBr(continueBB); 1802 1803 Builder.SetInsertPoint(continueBB); 1804 llvm::PHINode *phi = Builder.CreatePHI(opTy); 1805 phi->reserveOperandSpace(2); 1806 phi->addIncoming(result, initialBB); 1807 phi->addIncoming(handlerResult, overflowBB); 1808 1809 return phi; 1810} 1811 1812Value *ScalarExprEmitter::EmitAdd(const BinOpInfo &Ops) { 1813 if (!Ops.Ty->isAnyPointerType()) { 1814 if (Ops.Ty->hasSignedIntegerRepresentation()) { 1815 switch (CGF.getContext().getLangOptions().getSignedOverflowBehavior()) { 1816 case LangOptions::SOB_Undefined: 1817 return Builder.CreateNSWAdd(Ops.LHS, Ops.RHS, "add"); 1818 case LangOptions::SOB_Defined: 1819 return Builder.CreateAdd(Ops.LHS, Ops.RHS, "add"); 1820 case LangOptions::SOB_Trapping: 1821 return EmitOverflowCheckedBinOp(Ops); 1822 } 1823 } 1824 1825 if (Ops.LHS->getType()->isFPOrFPVectorTy()) 1826 return Builder.CreateFAdd(Ops.LHS, Ops.RHS, "add"); 1827 1828 return Builder.CreateAdd(Ops.LHS, Ops.RHS, "add"); 1829 } 1830 1831 // Must have binary (not unary) expr here. Unary pointer decrement doesn't 1832 // use this path. 1833 const BinaryOperator *BinOp = cast<BinaryOperator>(Ops.E); 1834 1835 if (Ops.Ty->isPointerType() && 1836 Ops.Ty->getAs<PointerType>()->isVariableArrayType()) { 1837 // The amount of the addition needs to account for the VLA size 1838 CGF.ErrorUnsupported(BinOp, "VLA pointer addition"); 1839 } 1840 1841 Value *Ptr, *Idx; 1842 Expr *IdxExp; 1843 const PointerType *PT = BinOp->getLHS()->getType()->getAs<PointerType>(); 1844 const ObjCObjectPointerType *OPT = 1845 BinOp->getLHS()->getType()->getAs<ObjCObjectPointerType>(); 1846 if (PT || OPT) { 1847 Ptr = Ops.LHS; 1848 Idx = Ops.RHS; 1849 IdxExp = BinOp->getRHS(); 1850 } else { // int + pointer 1851 PT = BinOp->getRHS()->getType()->getAs<PointerType>(); 1852 OPT = BinOp->getRHS()->getType()->getAs<ObjCObjectPointerType>(); 1853 assert((PT || OPT) && "Invalid add expr"); 1854 Ptr = Ops.RHS; 1855 Idx = Ops.LHS; 1856 IdxExp = BinOp->getLHS(); 1857 } 1858 1859 unsigned Width = cast<llvm::IntegerType>(Idx->getType())->getBitWidth(); 1860 if (Width < CGF.PointerWidthInBits) { 1861 // Zero or sign extend the pointer value based on whether the index is 1862 // signed or not. 1863 const llvm::Type *IdxType = CGF.IntPtrTy; 1864 if (IdxExp->getType()->isSignedIntegerType()) 1865 Idx = Builder.CreateSExt(Idx, IdxType, "idx.ext"); 1866 else 1867 Idx = Builder.CreateZExt(Idx, IdxType, "idx.ext"); 1868 } 1869 const QualType ElementType = PT ? PT->getPointeeType() : OPT->getPointeeType(); 1870 // Handle interface types, which are not represented with a concrete type. 1871 if (const ObjCObjectType *OIT = ElementType->getAs<ObjCObjectType>()) { 1872 llvm::Value *InterfaceSize = 1873 llvm::ConstantInt::get(Idx->getType(), 1874 CGF.getContext().getTypeSizeInChars(OIT).getQuantity()); 1875 Idx = Builder.CreateMul(Idx, InterfaceSize); 1876 const llvm::Type *i8Ty = llvm::Type::getInt8PtrTy(VMContext); 1877 Value *Casted = Builder.CreateBitCast(Ptr, i8Ty); 1878 Value *Res = Builder.CreateGEP(Casted, Idx, "add.ptr"); 1879 return Builder.CreateBitCast(Res, Ptr->getType()); 1880 } 1881 1882 // Explicitly handle GNU void* and function pointer arithmetic extensions. The 1883 // GNU void* casts amount to no-ops since our void* type is i8*, but this is 1884 // future proof. 1885 if (ElementType->isVoidType() || ElementType->isFunctionType()) { 1886 const llvm::Type *i8Ty = llvm::Type::getInt8PtrTy(VMContext); 1887 Value *Casted = Builder.CreateBitCast(Ptr, i8Ty); 1888 Value *Res = Builder.CreateGEP(Casted, Idx, "add.ptr"); 1889 return Builder.CreateBitCast(Res, Ptr->getType()); 1890 } 1891 1892 return Builder.CreateInBoundsGEP(Ptr, Idx, "add.ptr"); 1893} 1894 1895Value *ScalarExprEmitter::EmitSub(const BinOpInfo &Ops) { 1896 if (!isa<llvm::PointerType>(Ops.LHS->getType())) { 1897 if (Ops.Ty->hasSignedIntegerRepresentation()) { 1898 switch (CGF.getContext().getLangOptions().getSignedOverflowBehavior()) { 1899 case LangOptions::SOB_Undefined: 1900 return Builder.CreateNSWSub(Ops.LHS, Ops.RHS, "sub"); 1901 case LangOptions::SOB_Defined: 1902 return Builder.CreateSub(Ops.LHS, Ops.RHS, "sub"); 1903 case LangOptions::SOB_Trapping: 1904 return EmitOverflowCheckedBinOp(Ops); 1905 } 1906 } 1907 1908 if (Ops.LHS->getType()->isFPOrFPVectorTy()) 1909 return Builder.CreateFSub(Ops.LHS, Ops.RHS, "sub"); 1910 1911 return Builder.CreateSub(Ops.LHS, Ops.RHS, "sub"); 1912 } 1913 1914 // Must have binary (not unary) expr here. Unary pointer increment doesn't 1915 // use this path. 1916 const BinaryOperator *BinOp = cast<BinaryOperator>(Ops.E); 1917 1918 if (BinOp->getLHS()->getType()->isPointerType() && 1919 BinOp->getLHS()->getType()->getAs<PointerType>()->isVariableArrayType()) { 1920 // The amount of the addition needs to account for the VLA size for 1921 // ptr-int 1922 // The amount of the division needs to account for the VLA size for 1923 // ptr-ptr. 1924 CGF.ErrorUnsupported(BinOp, "VLA pointer subtraction"); 1925 } 1926 1927 const QualType LHSType = BinOp->getLHS()->getType(); 1928 const QualType LHSElementType = LHSType->getPointeeType(); 1929 if (!isa<llvm::PointerType>(Ops.RHS->getType())) { 1930 // pointer - int 1931 Value *Idx = Ops.RHS; 1932 unsigned Width = cast<llvm::IntegerType>(Idx->getType())->getBitWidth(); 1933 if (Width < CGF.PointerWidthInBits) { 1934 // Zero or sign extend the pointer value based on whether the index is 1935 // signed or not. 1936 const llvm::Type *IdxType = CGF.IntPtrTy; 1937 if (BinOp->getRHS()->getType()->isSignedIntegerType()) 1938 Idx = Builder.CreateSExt(Idx, IdxType, "idx.ext"); 1939 else 1940 Idx = Builder.CreateZExt(Idx, IdxType, "idx.ext"); 1941 } 1942 Idx = Builder.CreateNeg(Idx, "sub.ptr.neg"); 1943 1944 // Handle interface types, which are not represented with a concrete type. 1945 if (const ObjCObjectType *OIT = LHSElementType->getAs<ObjCObjectType>()) { 1946 llvm::Value *InterfaceSize = 1947 llvm::ConstantInt::get(Idx->getType(), 1948 CGF.getContext(). 1949 getTypeSizeInChars(OIT).getQuantity()); 1950 Idx = Builder.CreateMul(Idx, InterfaceSize); 1951 const llvm::Type *i8Ty = llvm::Type::getInt8PtrTy(VMContext); 1952 Value *LHSCasted = Builder.CreateBitCast(Ops.LHS, i8Ty); 1953 Value *Res = Builder.CreateGEP(LHSCasted, Idx, "add.ptr"); 1954 return Builder.CreateBitCast(Res, Ops.LHS->getType()); 1955 } 1956 1957 // Explicitly handle GNU void* and function pointer arithmetic 1958 // extensions. The GNU void* casts amount to no-ops since our void* type is 1959 // i8*, but this is future proof. 1960 if (LHSElementType->isVoidType() || LHSElementType->isFunctionType()) { 1961 const llvm::Type *i8Ty = llvm::Type::getInt8PtrTy(VMContext); 1962 Value *LHSCasted = Builder.CreateBitCast(Ops.LHS, i8Ty); 1963 Value *Res = Builder.CreateGEP(LHSCasted, Idx, "sub.ptr"); 1964 return Builder.CreateBitCast(Res, Ops.LHS->getType()); 1965 } 1966 1967 return Builder.CreateInBoundsGEP(Ops.LHS, Idx, "sub.ptr"); 1968 } else { 1969 // pointer - pointer 1970 Value *LHS = Ops.LHS; 1971 Value *RHS = Ops.RHS; 1972 1973 CharUnits ElementSize; 1974 1975 // Handle GCC extension for pointer arithmetic on void* and function pointer 1976 // types. 1977 if (LHSElementType->isVoidType() || LHSElementType->isFunctionType()) { 1978 ElementSize = CharUnits::One(); 1979 } else { 1980 ElementSize = CGF.getContext().getTypeSizeInChars(LHSElementType); 1981 } 1982 1983 const llvm::Type *ResultType = ConvertType(Ops.Ty); 1984 LHS = Builder.CreatePtrToInt(LHS, ResultType, "sub.ptr.lhs.cast"); 1985 RHS = Builder.CreatePtrToInt(RHS, ResultType, "sub.ptr.rhs.cast"); 1986 Value *BytesBetween = Builder.CreateSub(LHS, RHS, "sub.ptr.sub"); 1987 1988 // Optimize out the shift for element size of 1. 1989 if (ElementSize.isOne()) 1990 return BytesBetween; 1991 1992 // Otherwise, do a full sdiv. This uses the "exact" form of sdiv, since 1993 // pointer difference in C is only defined in the case where both operands 1994 // are pointing to elements of an array. 1995 Value *BytesPerElt = 1996 llvm::ConstantInt::get(ResultType, ElementSize.getQuantity()); 1997 return Builder.CreateExactSDiv(BytesBetween, BytesPerElt, "sub.ptr.div"); 1998 } 1999} 2000 2001Value *ScalarExprEmitter::EmitShl(const BinOpInfo &Ops) { 2002 // LLVM requires the LHS and RHS to be the same type: promote or truncate the 2003 // RHS to the same size as the LHS. 2004 Value *RHS = Ops.RHS; 2005 if (Ops.LHS->getType() != RHS->getType()) 2006 RHS = Builder.CreateIntCast(RHS, Ops.LHS->getType(), false, "sh_prom"); 2007 2008 if (CGF.CatchUndefined 2009 && isa<llvm::IntegerType>(Ops.LHS->getType())) { 2010 unsigned Width = cast<llvm::IntegerType>(Ops.LHS->getType())->getBitWidth(); 2011 llvm::BasicBlock *Cont = CGF.createBasicBlock("cont"); 2012 CGF.Builder.CreateCondBr(Builder.CreateICmpULT(RHS, 2013 llvm::ConstantInt::get(RHS->getType(), Width)), 2014 Cont, CGF.getTrapBB()); 2015 CGF.EmitBlock(Cont); 2016 } 2017 2018 return Builder.CreateShl(Ops.LHS, RHS, "shl"); 2019} 2020 2021Value *ScalarExprEmitter::EmitShr(const BinOpInfo &Ops) { 2022 // LLVM requires the LHS and RHS to be the same type: promote or truncate the 2023 // RHS to the same size as the LHS. 2024 Value *RHS = Ops.RHS; 2025 if (Ops.LHS->getType() != RHS->getType()) 2026 RHS = Builder.CreateIntCast(RHS, Ops.LHS->getType(), false, "sh_prom"); 2027 2028 if (CGF.CatchUndefined 2029 && isa<llvm::IntegerType>(Ops.LHS->getType())) { 2030 unsigned Width = cast<llvm::IntegerType>(Ops.LHS->getType())->getBitWidth(); 2031 llvm::BasicBlock *Cont = CGF.createBasicBlock("cont"); 2032 CGF.Builder.CreateCondBr(Builder.CreateICmpULT(RHS, 2033 llvm::ConstantInt::get(RHS->getType(), Width)), 2034 Cont, CGF.getTrapBB()); 2035 CGF.EmitBlock(Cont); 2036 } 2037 2038 if (Ops.Ty->hasUnsignedIntegerRepresentation()) 2039 return Builder.CreateLShr(Ops.LHS, RHS, "shr"); 2040 return Builder.CreateAShr(Ops.LHS, RHS, "shr"); 2041} 2042 2043enum IntrinsicType { VCMPEQ, VCMPGT }; 2044// return corresponding comparison intrinsic for given vector type 2045static llvm::Intrinsic::ID GetIntrinsic(IntrinsicType IT, 2046 BuiltinType::Kind ElemKind) { 2047 switch (ElemKind) { 2048 default: assert(0 && "unexpected element type"); 2049 case BuiltinType::Char_U: 2050 case BuiltinType::UChar: 2051 return (IT == VCMPEQ) ? llvm::Intrinsic::ppc_altivec_vcmpequb_p : 2052 llvm::Intrinsic::ppc_altivec_vcmpgtub_p; 2053 break; 2054 case BuiltinType::Char_S: 2055 case BuiltinType::SChar: 2056 return (IT == VCMPEQ) ? llvm::Intrinsic::ppc_altivec_vcmpequb_p : 2057 llvm::Intrinsic::ppc_altivec_vcmpgtsb_p; 2058 break; 2059 case BuiltinType::UShort: 2060 return (IT == VCMPEQ) ? llvm::Intrinsic::ppc_altivec_vcmpequh_p : 2061 llvm::Intrinsic::ppc_altivec_vcmpgtuh_p; 2062 break; 2063 case BuiltinType::Short: 2064 return (IT == VCMPEQ) ? llvm::Intrinsic::ppc_altivec_vcmpequh_p : 2065 llvm::Intrinsic::ppc_altivec_vcmpgtsh_p; 2066 break; 2067 case BuiltinType::UInt: 2068 case BuiltinType::ULong: 2069 return (IT == VCMPEQ) ? llvm::Intrinsic::ppc_altivec_vcmpequw_p : 2070 llvm::Intrinsic::ppc_altivec_vcmpgtuw_p; 2071 break; 2072 case BuiltinType::Int: 2073 case BuiltinType::Long: 2074 return (IT == VCMPEQ) ? llvm::Intrinsic::ppc_altivec_vcmpequw_p : 2075 llvm::Intrinsic::ppc_altivec_vcmpgtsw_p; 2076 break; 2077 case BuiltinType::Float: 2078 return (IT == VCMPEQ) ? llvm::Intrinsic::ppc_altivec_vcmpeqfp_p : 2079 llvm::Intrinsic::ppc_altivec_vcmpgtfp_p; 2080 break; 2081 } 2082 return llvm::Intrinsic::not_intrinsic; 2083} 2084 2085Value *ScalarExprEmitter::EmitCompare(const BinaryOperator *E,unsigned UICmpOpc, 2086 unsigned SICmpOpc, unsigned FCmpOpc) { 2087 TestAndClearIgnoreResultAssign(); 2088 Value *Result; 2089 QualType LHSTy = E->getLHS()->getType(); 2090 if (const MemberPointerType *MPT = LHSTy->getAs<MemberPointerType>()) { 2091 assert(E->getOpcode() == BO_EQ || 2092 E->getOpcode() == BO_NE); 2093 Value *LHS = CGF.EmitScalarExpr(E->getLHS()); 2094 Value *RHS = CGF.EmitScalarExpr(E->getRHS()); 2095 Result = CGF.CGM.getCXXABI().EmitMemberPointerComparison( 2096 CGF, LHS, RHS, MPT, E->getOpcode() == BO_NE); 2097 } else if (!LHSTy->isAnyComplexType()) { 2098 Value *LHS = Visit(E->getLHS()); 2099 Value *RHS = Visit(E->getRHS()); 2100 2101 // If AltiVec, the comparison results in a numeric type, so we use 2102 // intrinsics comparing vectors and giving 0 or 1 as a result 2103 if (LHSTy->isVectorType() && CGF.getContext().getLangOptions().AltiVec) { 2104 // constants for mapping CR6 register bits to predicate result 2105 enum { CR6_EQ=0, CR6_EQ_REV, CR6_LT, CR6_LT_REV } CR6; 2106 2107 llvm::Intrinsic::ID ID = llvm::Intrinsic::not_intrinsic; 2108 2109 // in several cases vector arguments order will be reversed 2110 Value *FirstVecArg = LHS, 2111 *SecondVecArg = RHS; 2112 2113 QualType ElTy = LHSTy->getAs<VectorType>()->getElementType(); 2114 const BuiltinType *BTy = ElTy->getAs<BuiltinType>(); 2115 BuiltinType::Kind ElementKind = BTy->getKind(); 2116 2117 switch(E->getOpcode()) { 2118 default: assert(0 && "is not a comparison operation"); 2119 case BO_EQ: 2120 CR6 = CR6_LT; 2121 ID = GetIntrinsic(VCMPEQ, ElementKind); 2122 break; 2123 case BO_NE: 2124 CR6 = CR6_EQ; 2125 ID = GetIntrinsic(VCMPEQ, ElementKind); 2126 break; 2127 case BO_LT: 2128 CR6 = CR6_LT; 2129 ID = GetIntrinsic(VCMPGT, ElementKind); 2130 std::swap(FirstVecArg, SecondVecArg); 2131 break; 2132 case BO_GT: 2133 CR6 = CR6_LT; 2134 ID = GetIntrinsic(VCMPGT, ElementKind); 2135 break; 2136 case BO_LE: 2137 if (ElementKind == BuiltinType::Float) { 2138 CR6 = CR6_LT; 2139 ID = llvm::Intrinsic::ppc_altivec_vcmpgefp_p; 2140 std::swap(FirstVecArg, SecondVecArg); 2141 } 2142 else { 2143 CR6 = CR6_EQ; 2144 ID = GetIntrinsic(VCMPGT, ElementKind); 2145 } 2146 break; 2147 case BO_GE: 2148 if (ElementKind == BuiltinType::Float) { 2149 CR6 = CR6_LT; 2150 ID = llvm::Intrinsic::ppc_altivec_vcmpgefp_p; 2151 } 2152 else { 2153 CR6 = CR6_EQ; 2154 ID = GetIntrinsic(VCMPGT, ElementKind); 2155 std::swap(FirstVecArg, SecondVecArg); 2156 } 2157 break; 2158 } 2159 2160 Value *CR6Param = llvm::ConstantInt::get(CGF.Int32Ty, CR6); 2161 llvm::Function *F = CGF.CGM.getIntrinsic(ID); 2162 Result = Builder.CreateCall3(F, CR6Param, FirstVecArg, SecondVecArg, ""); 2163 return EmitScalarConversion(Result, CGF.getContext().BoolTy, E->getType()); 2164 } 2165 2166 if (LHS->getType()->isFPOrFPVectorTy()) { 2167 Result = Builder.CreateFCmp((llvm::CmpInst::Predicate)FCmpOpc, 2168 LHS, RHS, "cmp"); 2169 } else if (LHSTy->hasSignedIntegerRepresentation()) { 2170 Result = Builder.CreateICmp((llvm::ICmpInst::Predicate)SICmpOpc, 2171 LHS, RHS, "cmp"); 2172 } else { 2173 // Unsigned integers and pointers. 2174 Result = Builder.CreateICmp((llvm::ICmpInst::Predicate)UICmpOpc, 2175 LHS, RHS, "cmp"); 2176 } 2177 2178 // If this is a vector comparison, sign extend the result to the appropriate 2179 // vector integer type and return it (don't convert to bool). 2180 if (LHSTy->isVectorType()) 2181 return Builder.CreateSExt(Result, ConvertType(E->getType()), "sext"); 2182 2183 } else { 2184 // Complex Comparison: can only be an equality comparison. 2185 CodeGenFunction::ComplexPairTy LHS = CGF.EmitComplexExpr(E->getLHS()); 2186 CodeGenFunction::ComplexPairTy RHS = CGF.EmitComplexExpr(E->getRHS()); 2187 2188 QualType CETy = LHSTy->getAs<ComplexType>()->getElementType(); 2189 2190 Value *ResultR, *ResultI; 2191 if (CETy->isRealFloatingType()) { 2192 ResultR = Builder.CreateFCmp((llvm::FCmpInst::Predicate)FCmpOpc, 2193 LHS.first, RHS.first, "cmp.r"); 2194 ResultI = Builder.CreateFCmp((llvm::FCmpInst::Predicate)FCmpOpc, 2195 LHS.second, RHS.second, "cmp.i"); 2196 } else { 2197 // Complex comparisons can only be equality comparisons. As such, signed 2198 // and unsigned opcodes are the same. 2199 ResultR = Builder.CreateICmp((llvm::ICmpInst::Predicate)UICmpOpc, 2200 LHS.first, RHS.first, "cmp.r"); 2201 ResultI = Builder.CreateICmp((llvm::ICmpInst::Predicate)UICmpOpc, 2202 LHS.second, RHS.second, "cmp.i"); 2203 } 2204 2205 if (E->getOpcode() == BO_EQ) { 2206 Result = Builder.CreateAnd(ResultR, ResultI, "and.ri"); 2207 } else { 2208 assert(E->getOpcode() == BO_NE && 2209 "Complex comparison other than == or != ?"); 2210 Result = Builder.CreateOr(ResultR, ResultI, "or.ri"); 2211 } 2212 } 2213 2214 return EmitScalarConversion(Result, CGF.getContext().BoolTy, E->getType()); 2215} 2216 2217Value *ScalarExprEmitter::VisitBinAssign(const BinaryOperator *E) { 2218 bool Ignore = TestAndClearIgnoreResultAssign(); 2219 2220 // __block variables need to have the rhs evaluated first, plus this should 2221 // improve codegen just a little. 2222 Value *RHS = Visit(E->getRHS()); 2223 LValue LHS = EmitCheckedLValue(E->getLHS()); 2224 2225 // Store the value into the LHS. Bit-fields are handled specially 2226 // because the result is altered by the store, i.e., [C99 6.5.16p1] 2227 // 'An assignment expression has the value of the left operand after 2228 // the assignment...'. 2229 if (LHS.isBitField()) 2230 CGF.EmitStoreThroughBitfieldLValue(RValue::get(RHS), LHS, E->getType(), 2231 &RHS); 2232 else 2233 CGF.EmitStoreThroughLValue(RValue::get(RHS), LHS, E->getType()); 2234 2235 // If the result is clearly ignored, return now. 2236 if (Ignore) 2237 return 0; 2238 2239 // The result of an assignment in C is the assigned r-value. 2240 if (!CGF.getContext().getLangOptions().CPlusPlus) 2241 return RHS; 2242 2243 // Objective-C property assignment never reloads the value following a store. 2244 if (LHS.isPropertyRef()) 2245 return RHS; 2246 2247 // If the lvalue is non-volatile, return the computed value of the assignment. 2248 if (!LHS.isVolatileQualified()) 2249 return RHS; 2250 2251 // Otherwise, reload the value. 2252 return EmitLoadOfLValue(LHS, E->getType()); 2253} 2254 2255Value *ScalarExprEmitter::VisitBinLAnd(const BinaryOperator *E) { 2256 const llvm::Type *ResTy = ConvertType(E->getType()); 2257 2258 // If we have 0 && RHS, see if we can elide RHS, if so, just return 0. 2259 // If we have 1 && X, just emit X without inserting the control flow. 2260 bool LHSCondVal; 2261 if (CGF.ConstantFoldsToSimpleInteger(E->getLHS(), LHSCondVal)) { 2262 if (LHSCondVal) { // If we have 1 && X, just emit X. 2263 Value *RHSCond = CGF.EvaluateExprAsBool(E->getRHS()); 2264 // ZExt result to int or bool. 2265 return Builder.CreateZExtOrBitCast(RHSCond, ResTy, "land.ext"); 2266 } 2267 2268 // 0 && RHS: If it is safe, just elide the RHS, and return 0/false. 2269 if (!CGF.ContainsLabel(E->getRHS())) 2270 return llvm::Constant::getNullValue(ResTy); 2271 } 2272 2273 llvm::BasicBlock *ContBlock = CGF.createBasicBlock("land.end"); 2274 llvm::BasicBlock *RHSBlock = CGF.createBasicBlock("land.rhs"); 2275 2276 CodeGenFunction::ConditionalEvaluation eval(CGF); 2277 2278 // Branch on the LHS first. If it is false, go to the failure (cont) block. 2279 CGF.EmitBranchOnBoolExpr(E->getLHS(), RHSBlock, ContBlock); 2280 2281 // Any edges into the ContBlock are now from an (indeterminate number of) 2282 // edges from this first condition. All of these values will be false. Start 2283 // setting up the PHI node in the Cont Block for this. 2284 llvm::PHINode *PN = llvm::PHINode::Create(llvm::Type::getInt1Ty(VMContext), 2285 "", ContBlock); 2286 PN->reserveOperandSpace(2); // Normal case, two inputs. 2287 for (llvm::pred_iterator PI = pred_begin(ContBlock), PE = pred_end(ContBlock); 2288 PI != PE; ++PI) 2289 PN->addIncoming(llvm::ConstantInt::getFalse(VMContext), *PI); 2290 2291 eval.begin(CGF); 2292 CGF.EmitBlock(RHSBlock); 2293 Value *RHSCond = CGF.EvaluateExprAsBool(E->getRHS()); 2294 eval.end(CGF); 2295 2296 // Reaquire the RHS block, as there may be subblocks inserted. 2297 RHSBlock = Builder.GetInsertBlock(); 2298 2299 // Emit an unconditional branch from this block to ContBlock. Insert an entry 2300 // into the phi node for the edge with the value of RHSCond. 2301 CGF.EmitBlock(ContBlock); 2302 PN->addIncoming(RHSCond, RHSBlock); 2303 2304 // ZExt result to int. 2305 return Builder.CreateZExtOrBitCast(PN, ResTy, "land.ext"); 2306} 2307 2308Value *ScalarExprEmitter::VisitBinLOr(const BinaryOperator *E) { 2309 const llvm::Type *ResTy = ConvertType(E->getType()); 2310 2311 // If we have 1 || RHS, see if we can elide RHS, if so, just return 1. 2312 // If we have 0 || X, just emit X without inserting the control flow. 2313 bool LHSCondVal; 2314 if (CGF.ConstantFoldsToSimpleInteger(E->getLHS(), LHSCondVal)) { 2315 if (!LHSCondVal) { // If we have 0 || X, just emit X. 2316 Value *RHSCond = CGF.EvaluateExprAsBool(E->getRHS()); 2317 // ZExt result to int or bool. 2318 return Builder.CreateZExtOrBitCast(RHSCond, ResTy, "lor.ext"); 2319 } 2320 2321 // 1 || RHS: If it is safe, just elide the RHS, and return 1/true. 2322 if (!CGF.ContainsLabel(E->getRHS())) 2323 return llvm::ConstantInt::get(ResTy, 1); 2324 } 2325 2326 llvm::BasicBlock *ContBlock = CGF.createBasicBlock("lor.end"); 2327 llvm::BasicBlock *RHSBlock = CGF.createBasicBlock("lor.rhs"); 2328 2329 CodeGenFunction::ConditionalEvaluation eval(CGF); 2330 2331 // Branch on the LHS first. If it is true, go to the success (cont) block. 2332 CGF.EmitBranchOnBoolExpr(E->getLHS(), ContBlock, RHSBlock); 2333 2334 // Any edges into the ContBlock are now from an (indeterminate number of) 2335 // edges from this first condition. All of these values will be true. Start 2336 // setting up the PHI node in the Cont Block for this. 2337 llvm::PHINode *PN = llvm::PHINode::Create(llvm::Type::getInt1Ty(VMContext), 2338 "", ContBlock); 2339 PN->reserveOperandSpace(2); // Normal case, two inputs. 2340 for (llvm::pred_iterator PI = pred_begin(ContBlock), PE = pred_end(ContBlock); 2341 PI != PE; ++PI) 2342 PN->addIncoming(llvm::ConstantInt::getTrue(VMContext), *PI); 2343 2344 eval.begin(CGF); 2345 2346 // Emit the RHS condition as a bool value. 2347 CGF.EmitBlock(RHSBlock); 2348 Value *RHSCond = CGF.EvaluateExprAsBool(E->getRHS()); 2349 2350 eval.end(CGF); 2351 2352 // Reaquire the RHS block, as there may be subblocks inserted. 2353 RHSBlock = Builder.GetInsertBlock(); 2354 2355 // Emit an unconditional branch from this block to ContBlock. Insert an entry 2356 // into the phi node for the edge with the value of RHSCond. 2357 CGF.EmitBlock(ContBlock); 2358 PN->addIncoming(RHSCond, RHSBlock); 2359 2360 // ZExt result to int. 2361 return Builder.CreateZExtOrBitCast(PN, ResTy, "lor.ext"); 2362} 2363 2364Value *ScalarExprEmitter::VisitBinComma(const BinaryOperator *E) { 2365 CGF.EmitIgnoredExpr(E->getLHS()); 2366 CGF.EnsureInsertPoint(); 2367 return Visit(E->getRHS()); 2368} 2369 2370//===----------------------------------------------------------------------===// 2371// Other Operators 2372//===----------------------------------------------------------------------===// 2373 2374/// isCheapEnoughToEvaluateUnconditionally - Return true if the specified 2375/// expression is cheap enough and side-effect-free enough to evaluate 2376/// unconditionally instead of conditionally. This is used to convert control 2377/// flow into selects in some cases. 2378static bool isCheapEnoughToEvaluateUnconditionally(const Expr *E, 2379 CodeGenFunction &CGF) { 2380 if (const ParenExpr *PE = dyn_cast<ParenExpr>(E)) 2381 return isCheapEnoughToEvaluateUnconditionally(PE->getSubExpr(), CGF); 2382 2383 // TODO: Allow anything we can constant fold to an integer or fp constant. 2384 if (isa<IntegerLiteral>(E) || isa<CharacterLiteral>(E) || 2385 isa<FloatingLiteral>(E)) 2386 return true; 2387 2388 // Non-volatile automatic variables too, to get "cond ? X : Y" where 2389 // X and Y are local variables. 2390 if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(E)) 2391 if (const VarDecl *VD = dyn_cast<VarDecl>(DRE->getDecl())) 2392 if (VD->hasLocalStorage() && !(CGF.getContext() 2393 .getCanonicalType(VD->getType()) 2394 .isVolatileQualified())) 2395 return true; 2396 2397 return false; 2398} 2399 2400 2401Value *ScalarExprEmitter:: 2402VisitAbstractConditionalOperator(const AbstractConditionalOperator *E) { 2403 TestAndClearIgnoreResultAssign(); 2404 2405 // Bind the common expression if necessary. 2406 CodeGenFunction::OpaqueValueMapping binding(CGF, E); 2407 2408 Expr *condExpr = E->getCond(); 2409 Expr *lhsExpr = E->getTrueExpr(); 2410 Expr *rhsExpr = E->getFalseExpr(); 2411 2412 // If the condition constant folds and can be elided, try to avoid emitting 2413 // the condition and the dead arm. 2414 bool CondExprBool; 2415 if (CGF.ConstantFoldsToSimpleInteger(condExpr, CondExprBool)) { 2416 Expr *live = lhsExpr, *dead = rhsExpr; 2417 if (!CondExprBool) std::swap(live, dead); 2418 2419 // If the dead side doesn't have labels we need, and if the Live side isn't 2420 // the gnu missing ?: extension (which we could handle, but don't bother 2421 // to), just emit the Live part. 2422 if (!CGF.ContainsLabel(dead)) 2423 return Visit(live); 2424 } 2425 2426 // OpenCL: If the condition is a vector, we can treat this condition like 2427 // the select function. 2428 if (CGF.getContext().getLangOptions().OpenCL 2429 && condExpr->getType()->isVectorType()) { 2430 llvm::Value *CondV = CGF.EmitScalarExpr(condExpr); 2431 llvm::Value *LHS = Visit(lhsExpr); 2432 llvm::Value *RHS = Visit(rhsExpr); 2433 2434 const llvm::Type *condType = ConvertType(condExpr->getType()); 2435 const llvm::VectorType *vecTy = cast<llvm::VectorType>(condType); 2436 2437 unsigned numElem = vecTy->getNumElements(); 2438 const llvm::Type *elemType = vecTy->getElementType(); 2439 2440 std::vector<llvm::Constant*> Zvals; 2441 for (unsigned i = 0; i < numElem; ++i) 2442 Zvals.push_back(llvm::ConstantInt::get(elemType,0)); 2443 2444 llvm::Value *zeroVec = llvm::ConstantVector::get(Zvals); 2445 llvm::Value *TestMSB = Builder.CreateICmpSLT(CondV, zeroVec); 2446 llvm::Value *tmp = Builder.CreateSExt(TestMSB, 2447 llvm::VectorType::get(elemType, 2448 numElem), 2449 "sext"); 2450 llvm::Value *tmp2 = Builder.CreateNot(tmp); 2451 2452 // Cast float to int to perform ANDs if necessary. 2453 llvm::Value *RHSTmp = RHS; 2454 llvm::Value *LHSTmp = LHS; 2455 bool wasCast = false; 2456 const llvm::VectorType *rhsVTy = cast<llvm::VectorType>(RHS->getType()); 2457 if (rhsVTy->getElementType()->isFloatTy()) { 2458 RHSTmp = Builder.CreateBitCast(RHS, tmp2->getType()); 2459 LHSTmp = Builder.CreateBitCast(LHS, tmp->getType()); 2460 wasCast = true; 2461 } 2462 2463 llvm::Value *tmp3 = Builder.CreateAnd(RHSTmp, tmp2); 2464 llvm::Value *tmp4 = Builder.CreateAnd(LHSTmp, tmp); 2465 llvm::Value *tmp5 = Builder.CreateOr(tmp3, tmp4, "cond"); 2466 if (wasCast) 2467 tmp5 = Builder.CreateBitCast(tmp5, RHS->getType()); 2468 2469 return tmp5; 2470 } 2471 2472 // If this is a really simple expression (like x ? 4 : 5), emit this as a 2473 // select instead of as control flow. We can only do this if it is cheap and 2474 // safe to evaluate the LHS and RHS unconditionally. 2475 if (isCheapEnoughToEvaluateUnconditionally(lhsExpr, CGF) && 2476 isCheapEnoughToEvaluateUnconditionally(rhsExpr, CGF)) { 2477 llvm::Value *CondV = CGF.EvaluateExprAsBool(condExpr); 2478 llvm::Value *LHS = Visit(lhsExpr); 2479 llvm::Value *RHS = Visit(rhsExpr); 2480 return Builder.CreateSelect(CondV, LHS, RHS, "cond"); 2481 } 2482 2483 llvm::BasicBlock *LHSBlock = CGF.createBasicBlock("cond.true"); 2484 llvm::BasicBlock *RHSBlock = CGF.createBasicBlock("cond.false"); 2485 llvm::BasicBlock *ContBlock = CGF.createBasicBlock("cond.end"); 2486 2487 CodeGenFunction::ConditionalEvaluation eval(CGF); 2488 CGF.EmitBranchOnBoolExpr(condExpr, LHSBlock, RHSBlock); 2489 2490 CGF.EmitBlock(LHSBlock); 2491 eval.begin(CGF); 2492 Value *LHS = Visit(lhsExpr); 2493 eval.end(CGF); 2494 2495 LHSBlock = Builder.GetInsertBlock(); 2496 Builder.CreateBr(ContBlock); 2497 2498 CGF.EmitBlock(RHSBlock); 2499 eval.begin(CGF); 2500 Value *RHS = Visit(rhsExpr); 2501 eval.end(CGF); 2502 2503 RHSBlock = Builder.GetInsertBlock(); 2504 CGF.EmitBlock(ContBlock); 2505 2506 // If the LHS or RHS is a throw expression, it will be legitimately null. 2507 if (!LHS) 2508 return RHS; 2509 if (!RHS) 2510 return LHS; 2511 2512 // Create a PHI node for the real part. 2513 llvm::PHINode *PN = Builder.CreatePHI(LHS->getType(), "cond"); 2514 PN->reserveOperandSpace(2); 2515 PN->addIncoming(LHS, LHSBlock); 2516 PN->addIncoming(RHS, RHSBlock); 2517 return PN; 2518} 2519 2520Value *ScalarExprEmitter::VisitChooseExpr(ChooseExpr *E) { 2521 return Visit(E->getChosenSubExpr(CGF.getContext())); 2522} 2523 2524Value *ScalarExprEmitter::VisitVAArgExpr(VAArgExpr *VE) { 2525 llvm::Value *ArgValue = CGF.EmitVAListRef(VE->getSubExpr()); 2526 llvm::Value *ArgPtr = CGF.EmitVAArg(ArgValue, VE->getType()); 2527 2528 // If EmitVAArg fails, we fall back to the LLVM instruction. 2529 if (!ArgPtr) 2530 return Builder.CreateVAArg(ArgValue, ConvertType(VE->getType())); 2531 2532 // FIXME Volatility. 2533 return Builder.CreateLoad(ArgPtr); 2534} 2535 2536Value *ScalarExprEmitter::VisitBlockExpr(const BlockExpr *block) { 2537 return CGF.EmitBlockLiteral(block); 2538} 2539 2540//===----------------------------------------------------------------------===// 2541// Entry Point into this File 2542//===----------------------------------------------------------------------===// 2543 2544/// EmitScalarExpr - Emit the computation of the specified expression of scalar 2545/// type, ignoring the result. 2546Value *CodeGenFunction::EmitScalarExpr(const Expr *E, bool IgnoreResultAssign) { 2547 assert(E && !hasAggregateLLVMType(E->getType()) && 2548 "Invalid scalar expression to emit"); 2549 2550 return ScalarExprEmitter(*this, IgnoreResultAssign) 2551 .Visit(const_cast<Expr*>(E)); 2552} 2553 2554/// EmitScalarConversion - Emit a conversion from the specified type to the 2555/// specified destination type, both of which are LLVM scalar types. 2556Value *CodeGenFunction::EmitScalarConversion(Value *Src, QualType SrcTy, 2557 QualType DstTy) { 2558 assert(!hasAggregateLLVMType(SrcTy) && !hasAggregateLLVMType(DstTy) && 2559 "Invalid scalar expression to emit"); 2560 return ScalarExprEmitter(*this).EmitScalarConversion(Src, SrcTy, DstTy); 2561} 2562 2563/// EmitComplexToScalarConversion - Emit a conversion from the specified complex 2564/// type to the specified destination type, where the destination type is an 2565/// LLVM scalar type. 2566Value *CodeGenFunction::EmitComplexToScalarConversion(ComplexPairTy Src, 2567 QualType SrcTy, 2568 QualType DstTy) { 2569 assert(SrcTy->isAnyComplexType() && !hasAggregateLLVMType(DstTy) && 2570 "Invalid complex -> scalar conversion"); 2571 return ScalarExprEmitter(*this).EmitComplexToScalarConversion(Src, SrcTy, 2572 DstTy); 2573} 2574 2575 2576llvm::Value *CodeGenFunction:: 2577EmitScalarPrePostIncDec(const UnaryOperator *E, LValue LV, 2578 bool isInc, bool isPre) { 2579 return ScalarExprEmitter(*this).EmitScalarPrePostIncDec(E, LV, isInc, isPre); 2580} 2581 2582LValue CodeGenFunction::EmitObjCIsaExpr(const ObjCIsaExpr *E) { 2583 llvm::Value *V; 2584 // object->isa or (*object).isa 2585 // Generate code as for: *(Class*)object 2586 // build Class* type 2587 const llvm::Type *ClassPtrTy = ConvertType(E->getType()); 2588 2589 Expr *BaseExpr = E->getBase(); 2590 if (BaseExpr->isRValue()) { 2591 V = CreateTempAlloca(ClassPtrTy, "resval"); 2592 llvm::Value *Src = EmitScalarExpr(BaseExpr); 2593 Builder.CreateStore(Src, V); 2594 V = ScalarExprEmitter(*this).EmitLoadOfLValue( 2595 MakeAddrLValue(V, E->getType()), E->getType()); 2596 } else { 2597 if (E->isArrow()) 2598 V = ScalarExprEmitter(*this).EmitLoadOfLValue(BaseExpr); 2599 else 2600 V = EmitLValue(BaseExpr).getAddress(); 2601 } 2602 2603 // build Class* type 2604 ClassPtrTy = ClassPtrTy->getPointerTo(); 2605 V = Builder.CreateBitCast(V, ClassPtrTy); 2606 return MakeAddrLValue(V, E->getType()); 2607} 2608 2609 2610LValue CodeGenFunction::EmitCompoundAssignmentLValue( 2611 const CompoundAssignOperator *E) { 2612 ScalarExprEmitter Scalar(*this); 2613 Value *Result = 0; 2614 switch (E->getOpcode()) { 2615#define COMPOUND_OP(Op) \ 2616 case BO_##Op##Assign: \ 2617 return Scalar.EmitCompoundAssignLValue(E, &ScalarExprEmitter::Emit##Op, \ 2618 Result) 2619 COMPOUND_OP(Mul); 2620 COMPOUND_OP(Div); 2621 COMPOUND_OP(Rem); 2622 COMPOUND_OP(Add); 2623 COMPOUND_OP(Sub); 2624 COMPOUND_OP(Shl); 2625 COMPOUND_OP(Shr); 2626 COMPOUND_OP(And); 2627 COMPOUND_OP(Xor); 2628 COMPOUND_OP(Or); 2629#undef COMPOUND_OP 2630 2631 case BO_PtrMemD: 2632 case BO_PtrMemI: 2633 case BO_Mul: 2634 case BO_Div: 2635 case BO_Rem: 2636 case BO_Add: 2637 case BO_Sub: 2638 case BO_Shl: 2639 case BO_Shr: 2640 case BO_LT: 2641 case BO_GT: 2642 case BO_LE: 2643 case BO_GE: 2644 case BO_EQ: 2645 case BO_NE: 2646 case BO_And: 2647 case BO_Xor: 2648 case BO_Or: 2649 case BO_LAnd: 2650 case BO_LOr: 2651 case BO_Assign: 2652 case BO_Comma: 2653 assert(false && "Not valid compound assignment operators"); 2654 break; 2655 } 2656 2657 llvm_unreachable("Unhandled compound assignment operator"); 2658} 2659