CGExprScalar.cpp revision e04d45e05277ee04997fe59b1d194503f484c846
1ddb351dbec246cf1fab5ec20d2d5520909041de1Kristian Monsen//===--- CGExprScalar.cpp - Emit LLVM Code for Scalar Exprs ---------------===// 2513209b27ff55e2841eac0e4120199c23acce758Ben Murdoch// 3513209b27ff55e2841eac0e4120199c23acce758Ben Murdoch// The LLVM Compiler Infrastructure 4513209b27ff55e2841eac0e4120199c23acce758Ben Murdoch// 5513209b27ff55e2841eac0e4120199c23acce758Ben Murdoch// This file is distributed under the University of Illinois Open Source 6513209b27ff55e2841eac0e4120199c23acce758Ben Murdoch// License. See LICENSE.TXT for details. 7513209b27ff55e2841eac0e4120199c23acce758Ben Murdoch// 8513209b27ff55e2841eac0e4120199c23acce758Ben Murdoch//===----------------------------------------------------------------------===// 9513209b27ff55e2841eac0e4120199c23acce758Ben Murdoch// 10ddb351dbec246cf1fab5ec20d2d5520909041de1Kristian Monsen// This contains code to emit Expr nodes with scalar LLVM types as LLVM code. 11513209b27ff55e2841eac0e4120199c23acce758Ben Murdoch// 12513209b27ff55e2841eac0e4120199c23acce758Ben Murdoch//===----------------------------------------------------------------------===// 13513209b27ff55e2841eac0e4120199c23acce758Ben Murdoch 14513209b27ff55e2841eac0e4120199c23acce758Ben Murdoch#include "CodeGenFunction.h" 15513209b27ff55e2841eac0e4120199c23acce758Ben Murdoch#include "CGObjCRuntime.h" 16513209b27ff55e2841eac0e4120199c23acce758Ben Murdoch#include "CodeGenModule.h" 17513209b27ff55e2841eac0e4120199c23acce758Ben Murdoch#include "clang/AST/ASTContext.h" 18513209b27ff55e2841eac0e4120199c23acce758Ben Murdoch#include "clang/AST/DeclObjC.h" 19513209b27ff55e2841eac0e4120199c23acce758Ben Murdoch#include "clang/AST/RecordLayout.h" 20513209b27ff55e2841eac0e4120199c23acce758Ben Murdoch#include "clang/AST/StmtVisitor.h" 21513209b27ff55e2841eac0e4120199c23acce758Ben Murdoch#include "clang/Basic/TargetInfo.h" 22513209b27ff55e2841eac0e4120199c23acce758Ben Murdoch#include "llvm/Constants.h" 23513209b27ff55e2841eac0e4120199c23acce758Ben Murdoch#include "llvm/Function.h" 24513209b27ff55e2841eac0e4120199c23acce758Ben Murdoch#include "llvm/GlobalVariable.h" 25513209b27ff55e2841eac0e4120199c23acce758Ben Murdoch#include "llvm/Intrinsics.h" 26513209b27ff55e2841eac0e4120199c23acce758Ben Murdoch#include "llvm/Module.h" 27513209b27ff55e2841eac0e4120199c23acce758Ben Murdoch#include "llvm/Support/CFG.h" 28513209b27ff55e2841eac0e4120199c23acce758Ben Murdoch#include "llvm/Target/TargetData.h" 29513209b27ff55e2841eac0e4120199c23acce758Ben Murdoch#include <cstdarg> 30513209b27ff55e2841eac0e4120199c23acce758Ben Murdoch 31513209b27ff55e2841eac0e4120199c23acce758Ben Murdochusing namespace clang; 32513209b27ff55e2841eac0e4120199c23acce758Ben Murdochusing namespace CodeGen; 33513209b27ff55e2841eac0e4120199c23acce758Ben Murdochusing llvm::Value; 34513209b27ff55e2841eac0e4120199c23acce758Ben Murdoch 35513209b27ff55e2841eac0e4120199c23acce758Ben Murdoch//===----------------------------------------------------------------------===// 36513209b27ff55e2841eac0e4120199c23acce758Ben Murdoch// Scalar Expression Emitter 37513209b27ff55e2841eac0e4120199c23acce758Ben Murdoch//===----------------------------------------------------------------------===// 38513209b27ff55e2841eac0e4120199c23acce758Ben Murdoch 39513209b27ff55e2841eac0e4120199c23acce758Ben Murdochstruct BinOpInfo { 40513209b27ff55e2841eac0e4120199c23acce758Ben Murdoch Value *LHS; 41513209b27ff55e2841eac0e4120199c23acce758Ben Murdoch Value *RHS; 42513209b27ff55e2841eac0e4120199c23acce758Ben Murdoch QualType Ty; // Computation Type. 43513209b27ff55e2841eac0e4120199c23acce758Ben Murdoch const BinaryOperator *E; 44513209b27ff55e2841eac0e4120199c23acce758Ben Murdoch}; 45513209b27ff55e2841eac0e4120199c23acce758Ben Murdoch 46513209b27ff55e2841eac0e4120199c23acce758Ben Murdochnamespace { 47513209b27ff55e2841eac0e4120199c23acce758Ben Murdochclass ScalarExprEmitter 48513209b27ff55e2841eac0e4120199c23acce758Ben Murdoch : public StmtVisitor<ScalarExprEmitter, Value*> { 49513209b27ff55e2841eac0e4120199c23acce758Ben Murdoch CodeGenFunction &CGF; 50513209b27ff55e2841eac0e4120199c23acce758Ben Murdoch CGBuilderTy &Builder; 51513209b27ff55e2841eac0e4120199c23acce758Ben Murdoch bool IgnoreResultAssign; 52513209b27ff55e2841eac0e4120199c23acce758Ben Murdoch llvm::LLVMContext &VMContext; 53513209b27ff55e2841eac0e4120199c23acce758Ben Murdochpublic: 54513209b27ff55e2841eac0e4120199c23acce758Ben Murdoch 55513209b27ff55e2841eac0e4120199c23acce758Ben Murdoch ScalarExprEmitter(CodeGenFunction &cgf, bool ira=false) 56513209b27ff55e2841eac0e4120199c23acce758Ben Murdoch : CGF(cgf), Builder(CGF.Builder), IgnoreResultAssign(ira), 57513209b27ff55e2841eac0e4120199c23acce758Ben Murdoch VMContext(cgf.getLLVMContext()) { 58513209b27ff55e2841eac0e4120199c23acce758Ben Murdoch } 59513209b27ff55e2841eac0e4120199c23acce758Ben Murdoch 60513209b27ff55e2841eac0e4120199c23acce758Ben Murdoch //===--------------------------------------------------------------------===// 61513209b27ff55e2841eac0e4120199c23acce758Ben Murdoch // Utilities 62513209b27ff55e2841eac0e4120199c23acce758Ben Murdoch //===--------------------------------------------------------------------===// 63513209b27ff55e2841eac0e4120199c23acce758Ben Murdoch 64513209b27ff55e2841eac0e4120199c23acce758Ben Murdoch bool TestAndClearIgnoreResultAssign() { 65513209b27ff55e2841eac0e4120199c23acce758Ben Murdoch bool I = IgnoreResultAssign; 66513209b27ff55e2841eac0e4120199c23acce758Ben Murdoch IgnoreResultAssign = false; 67513209b27ff55e2841eac0e4120199c23acce758Ben Murdoch return I; 68513209b27ff55e2841eac0e4120199c23acce758Ben Murdoch } 69513209b27ff55e2841eac0e4120199c23acce758Ben Murdoch 70513209b27ff55e2841eac0e4120199c23acce758Ben Murdoch const llvm::Type *ConvertType(QualType T) { return CGF.ConvertType(T); } 71513209b27ff55e2841eac0e4120199c23acce758Ben Murdoch LValue EmitLValue(const Expr *E) { return CGF.EmitLValue(E); } 72513209b27ff55e2841eac0e4120199c23acce758Ben Murdoch LValue EmitCheckedLValue(const Expr *E) { return CGF.EmitCheckedLValue(E); } 73513209b27ff55e2841eac0e4120199c23acce758Ben Murdoch 74513209b27ff55e2841eac0e4120199c23acce758Ben Murdoch Value *EmitLoadOfLValue(LValue LV, QualType T) { 75513209b27ff55e2841eac0e4120199c23acce758Ben Murdoch return CGF.EmitLoadOfLValue(LV, T).getScalarVal(); 76513209b27ff55e2841eac0e4120199c23acce758Ben Murdoch } 77513209b27ff55e2841eac0e4120199c23acce758Ben Murdoch 78513209b27ff55e2841eac0e4120199c23acce758Ben Murdoch /// EmitLoadOfLValue - Given an expression with complex type that represents a 79513209b27ff55e2841eac0e4120199c23acce758Ben Murdoch /// value l-value, this method emits the address of the l-value, then loads 80513209b27ff55e2841eac0e4120199c23acce758Ben Murdoch /// and returns the result. 81513209b27ff55e2841eac0e4120199c23acce758Ben Murdoch Value *EmitLoadOfLValue(const Expr *E) { 82513209b27ff55e2841eac0e4120199c23acce758Ben Murdoch return EmitLoadOfLValue(EmitCheckedLValue(E), E->getType()); 83513209b27ff55e2841eac0e4120199c23acce758Ben Murdoch } 84513209b27ff55e2841eac0e4120199c23acce758Ben Murdoch 85513209b27ff55e2841eac0e4120199c23acce758Ben Murdoch /// EmitConversionToBool - Convert the specified expression value to a 86513209b27ff55e2841eac0e4120199c23acce758Ben Murdoch /// boolean (i1) truth value. This is equivalent to "Val != 0". 87513209b27ff55e2841eac0e4120199c23acce758Ben Murdoch Value *EmitConversionToBool(Value *Src, QualType DstTy); 88513209b27ff55e2841eac0e4120199c23acce758Ben Murdoch 89513209b27ff55e2841eac0e4120199c23acce758Ben Murdoch /// EmitScalarConversion - Emit a conversion from the specified type to the 90513209b27ff55e2841eac0e4120199c23acce758Ben Murdoch /// specified destination type, both of which are LLVM scalar types. 91513209b27ff55e2841eac0e4120199c23acce758Ben Murdoch Value *EmitScalarConversion(Value *Src, QualType SrcTy, QualType DstTy); 92513209b27ff55e2841eac0e4120199c23acce758Ben Murdoch 93513209b27ff55e2841eac0e4120199c23acce758Ben Murdoch /// EmitComplexToScalarConversion - Emit a conversion from the specified 94513209b27ff55e2841eac0e4120199c23acce758Ben Murdoch /// complex type to the specified destination type, where the destination type 95513209b27ff55e2841eac0e4120199c23acce758Ben Murdoch /// is an LLVM scalar type. 96513209b27ff55e2841eac0e4120199c23acce758Ben Murdoch Value *EmitComplexToScalarConversion(CodeGenFunction::ComplexPairTy Src, 97513209b27ff55e2841eac0e4120199c23acce758Ben Murdoch QualType SrcTy, QualType DstTy); 98513209b27ff55e2841eac0e4120199c23acce758Ben Murdoch 99513209b27ff55e2841eac0e4120199c23acce758Ben Murdoch //===--------------------------------------------------------------------===// 100513209b27ff55e2841eac0e4120199c23acce758Ben Murdoch // Visitor Methods 101513209b27ff55e2841eac0e4120199c23acce758Ben Murdoch //===--------------------------------------------------------------------===// 102513209b27ff55e2841eac0e4120199c23acce758Ben Murdoch 103513209b27ff55e2841eac0e4120199c23acce758Ben Murdoch Value *VisitStmt(Stmt *S) { 104 S->dump(CGF.getContext().getSourceManager()); 105 assert(0 && "Stmt can't have complex result type!"); 106 return 0; 107 } 108 Value *VisitExpr(Expr *S); 109 110 Value *VisitParenExpr(ParenExpr *PE) { return Visit(PE->getSubExpr()); } 111 112 // Leaves. 113 Value *VisitIntegerLiteral(const IntegerLiteral *E) { 114 return llvm::ConstantInt::get(VMContext, E->getValue()); 115 } 116 Value *VisitFloatingLiteral(const FloatingLiteral *E) { 117 return llvm::ConstantFP::get(VMContext, E->getValue()); 118 } 119 Value *VisitCharacterLiteral(const CharacterLiteral *E) { 120 return llvm::ConstantInt::get(ConvertType(E->getType()), E->getValue()); 121 } 122 Value *VisitCXXBoolLiteralExpr(const CXXBoolLiteralExpr *E) { 123 return llvm::ConstantInt::get(ConvertType(E->getType()), E->getValue()); 124 } 125 Value *VisitCXXZeroInitValueExpr(const CXXZeroInitValueExpr *E) { 126 return llvm::Constant::getNullValue(ConvertType(E->getType())); 127 } 128 Value *VisitGNUNullExpr(const GNUNullExpr *E) { 129 return llvm::Constant::getNullValue(ConvertType(E->getType())); 130 } 131 Value *VisitTypesCompatibleExpr(const TypesCompatibleExpr *E) { 132 return llvm::ConstantInt::get(ConvertType(E->getType()), 133 CGF.getContext().typesAreCompatible( 134 E->getArgType1(), E->getArgType2())); 135 } 136 Value *VisitSizeOfAlignOfExpr(const SizeOfAlignOfExpr *E); 137 Value *VisitAddrLabelExpr(const AddrLabelExpr *E) { 138 llvm::Value *V = CGF.GetAddrOfLabel(E->getLabel()); 139 return Builder.CreateBitCast(V, ConvertType(E->getType())); 140 } 141 142 // l-values. 143 Value *VisitDeclRefExpr(DeclRefExpr *E) { 144 Expr::EvalResult Result; 145 if (E->Evaluate(Result, CGF.getContext()) && Result.Val.isInt()) { 146 assert(!Result.HasSideEffects && "Constant declref with side-effect?!"); 147 return llvm::ConstantInt::get(VMContext, Result.Val.getInt()); 148 } 149 return EmitLoadOfLValue(E); 150 } 151 Value *VisitObjCSelectorExpr(ObjCSelectorExpr *E) { 152 return CGF.EmitObjCSelectorExpr(E); 153 } 154 Value *VisitObjCProtocolExpr(ObjCProtocolExpr *E) { 155 return CGF.EmitObjCProtocolExpr(E); 156 } 157 Value *VisitObjCIvarRefExpr(ObjCIvarRefExpr *E) { 158 return EmitLoadOfLValue(E); 159 } 160 Value *VisitObjCPropertyRefExpr(ObjCPropertyRefExpr *E) { 161 return EmitLoadOfLValue(E); 162 } 163 Value *VisitObjCImplicitSetterGetterRefExpr( 164 ObjCImplicitSetterGetterRefExpr *E) { 165 return EmitLoadOfLValue(E); 166 } 167 Value *VisitObjCMessageExpr(ObjCMessageExpr *E) { 168 return CGF.EmitObjCMessageExpr(E).getScalarVal(); 169 } 170 171 Value *VisitObjCIsaExpr(ObjCIsaExpr *E) { 172 LValue LV = CGF.EmitObjCIsaExpr(E); 173 Value *V = CGF.EmitLoadOfLValue(LV, E->getType()).getScalarVal(); 174 return V; 175 } 176 177 Value *VisitArraySubscriptExpr(ArraySubscriptExpr *E); 178 Value *VisitShuffleVectorExpr(ShuffleVectorExpr *E); 179 Value *VisitMemberExpr(MemberExpr *E); 180 Value *VisitExtVectorElementExpr(Expr *E) { return EmitLoadOfLValue(E); } 181 Value *VisitCompoundLiteralExpr(CompoundLiteralExpr *E) { 182 return EmitLoadOfLValue(E); 183 } 184 185 Value *VisitInitListExpr(InitListExpr *E); 186 187 Value *VisitImplicitValueInitExpr(const ImplicitValueInitExpr *E) { 188 return llvm::Constant::getNullValue(ConvertType(E->getType())); 189 } 190 Value *VisitCastExpr(CastExpr *E) { 191 // Make sure to evaluate VLA bounds now so that we have them for later. 192 if (E->getType()->isVariablyModifiedType()) 193 CGF.EmitVLASize(E->getType()); 194 195 return EmitCastExpr(E); 196 } 197 Value *EmitCastExpr(CastExpr *E); 198 199 Value *VisitCallExpr(const CallExpr *E) { 200 if (E->getCallReturnType()->isReferenceType()) 201 return EmitLoadOfLValue(E); 202 203 return CGF.EmitCallExpr(E).getScalarVal(); 204 } 205 206 Value *VisitStmtExpr(const StmtExpr *E); 207 208 Value *VisitBlockDeclRefExpr(const BlockDeclRefExpr *E); 209 210 // Unary Operators. 211 Value *VisitPrePostIncDec(const UnaryOperator *E, bool isInc, bool isPre) { 212 LValue LV = EmitLValue(E->getSubExpr()); 213 return CGF.EmitScalarPrePostIncDec(E, LV, isInc, isPre); 214 } 215 Value *VisitUnaryPostDec(const UnaryOperator *E) { 216 return VisitPrePostIncDec(E, false, false); 217 } 218 Value *VisitUnaryPostInc(const UnaryOperator *E) { 219 return VisitPrePostIncDec(E, true, false); 220 } 221 Value *VisitUnaryPreDec(const UnaryOperator *E) { 222 return VisitPrePostIncDec(E, false, true); 223 } 224 Value *VisitUnaryPreInc(const UnaryOperator *E) { 225 return VisitPrePostIncDec(E, true, true); 226 } 227 Value *VisitUnaryAddrOf(const UnaryOperator *E) { 228 return EmitLValue(E->getSubExpr()).getAddress(); 229 } 230 Value *VisitUnaryDeref(const Expr *E) { return EmitLoadOfLValue(E); } 231 Value *VisitUnaryPlus(const UnaryOperator *E) { 232 // This differs from gcc, though, most likely due to a bug in gcc. 233 TestAndClearIgnoreResultAssign(); 234 return Visit(E->getSubExpr()); 235 } 236 Value *VisitUnaryMinus (const UnaryOperator *E); 237 Value *VisitUnaryNot (const UnaryOperator *E); 238 Value *VisitUnaryLNot (const UnaryOperator *E); 239 Value *VisitUnaryReal (const UnaryOperator *E); 240 Value *VisitUnaryImag (const UnaryOperator *E); 241 Value *VisitUnaryExtension(const UnaryOperator *E) { 242 return Visit(E->getSubExpr()); 243 } 244 Value *VisitUnaryOffsetOf(const UnaryOperator *E); 245 246 // C++ 247 Value *VisitCXXDefaultArgExpr(CXXDefaultArgExpr *DAE) { 248 return Visit(DAE->getExpr()); 249 } 250 Value *VisitCXXThisExpr(CXXThisExpr *TE) { 251 return CGF.LoadCXXThis(); 252 } 253 254 Value *VisitCXXExprWithTemporaries(CXXExprWithTemporaries *E) { 255 return CGF.EmitCXXExprWithTemporaries(E).getScalarVal(); 256 } 257 Value *VisitCXXNewExpr(const CXXNewExpr *E) { 258 return CGF.EmitCXXNewExpr(E); 259 } 260 Value *VisitCXXDeleteExpr(const CXXDeleteExpr *E) { 261 CGF.EmitCXXDeleteExpr(E); 262 return 0; 263 } 264 Value *VisitUnaryTypeTraitExpr(const UnaryTypeTraitExpr *E) { 265 return llvm::ConstantInt::get(Builder.getInt1Ty(), 266 E->EvaluateTrait(CGF.getContext())); 267 } 268 269 Value *VisitCXXPseudoDestructorExpr(const CXXPseudoDestructorExpr *E) { 270 // C++ [expr.pseudo]p1: 271 // The result shall only be used as the operand for the function call 272 // operator (), and the result of such a call has type void. The only 273 // effect is the evaluation of the postfix-expression before the dot or 274 // arrow. 275 CGF.EmitScalarExpr(E->getBase()); 276 return 0; 277 } 278 279 Value *VisitCXXNullPtrLiteralExpr(const CXXNullPtrLiteralExpr *E) { 280 return llvm::Constant::getNullValue(ConvertType(E->getType())); 281 } 282 283 Value *VisitCXXThrowExpr(const CXXThrowExpr *E) { 284 CGF.EmitCXXThrowExpr(E); 285 return 0; 286 } 287 288 // Binary Operators. 289 Value *EmitMul(const BinOpInfo &Ops) { 290 if (CGF.getContext().getLangOptions().OverflowChecking 291 && Ops.Ty->isSignedIntegerType()) 292 return EmitOverflowCheckedBinOp(Ops); 293 if (Ops.LHS->getType()->isFPOrFPVectorTy()) 294 return Builder.CreateFMul(Ops.LHS, Ops.RHS, "mul"); 295 return Builder.CreateMul(Ops.LHS, Ops.RHS, "mul"); 296 } 297 /// Create a binary op that checks for overflow. 298 /// Currently only supports +, - and *. 299 Value *EmitOverflowCheckedBinOp(const BinOpInfo &Ops); 300 Value *EmitDiv(const BinOpInfo &Ops); 301 Value *EmitRem(const BinOpInfo &Ops); 302 Value *EmitAdd(const BinOpInfo &Ops); 303 Value *EmitSub(const BinOpInfo &Ops); 304 Value *EmitShl(const BinOpInfo &Ops); 305 Value *EmitShr(const BinOpInfo &Ops); 306 Value *EmitAnd(const BinOpInfo &Ops) { 307 return Builder.CreateAnd(Ops.LHS, Ops.RHS, "and"); 308 } 309 Value *EmitXor(const BinOpInfo &Ops) { 310 return Builder.CreateXor(Ops.LHS, Ops.RHS, "xor"); 311 } 312 Value *EmitOr (const BinOpInfo &Ops) { 313 return Builder.CreateOr(Ops.LHS, Ops.RHS, "or"); 314 } 315 316 BinOpInfo EmitBinOps(const BinaryOperator *E); 317 LValue EmitCompoundAssignLValue(const CompoundAssignOperator *E, 318 Value *(ScalarExprEmitter::*F)(const BinOpInfo &), 319 Value *&BitFieldResult); 320 321 Value *EmitCompoundAssign(const CompoundAssignOperator *E, 322 Value *(ScalarExprEmitter::*F)(const BinOpInfo &)); 323 324 // Binary operators and binary compound assignment operators. 325#define HANDLEBINOP(OP) \ 326 Value *VisitBin ## OP(const BinaryOperator *E) { \ 327 return Emit ## OP(EmitBinOps(E)); \ 328 } \ 329 Value *VisitBin ## OP ## Assign(const CompoundAssignOperator *E) { \ 330 return EmitCompoundAssign(E, &ScalarExprEmitter::Emit ## OP); \ 331 } 332 HANDLEBINOP(Mul) 333 HANDLEBINOP(Div) 334 HANDLEBINOP(Rem) 335 HANDLEBINOP(Add) 336 HANDLEBINOP(Sub) 337 HANDLEBINOP(Shl) 338 HANDLEBINOP(Shr) 339 HANDLEBINOP(And) 340 HANDLEBINOP(Xor) 341 HANDLEBINOP(Or) 342#undef HANDLEBINOP 343 344 // Comparisons. 345 Value *EmitCompare(const BinaryOperator *E, unsigned UICmpOpc, 346 unsigned SICmpOpc, unsigned FCmpOpc); 347#define VISITCOMP(CODE, UI, SI, FP) \ 348 Value *VisitBin##CODE(const BinaryOperator *E) { \ 349 return EmitCompare(E, llvm::ICmpInst::UI, llvm::ICmpInst::SI, \ 350 llvm::FCmpInst::FP); } 351 VISITCOMP(LT, ICMP_ULT, ICMP_SLT, FCMP_OLT) 352 VISITCOMP(GT, ICMP_UGT, ICMP_SGT, FCMP_OGT) 353 VISITCOMP(LE, ICMP_ULE, ICMP_SLE, FCMP_OLE) 354 VISITCOMP(GE, ICMP_UGE, ICMP_SGE, FCMP_OGE) 355 VISITCOMP(EQ, ICMP_EQ , ICMP_EQ , FCMP_OEQ) 356 VISITCOMP(NE, ICMP_NE , ICMP_NE , FCMP_UNE) 357#undef VISITCOMP 358 359 Value *VisitBinAssign (const BinaryOperator *E); 360 361 Value *VisitBinLAnd (const BinaryOperator *E); 362 Value *VisitBinLOr (const BinaryOperator *E); 363 Value *VisitBinComma (const BinaryOperator *E); 364 365 Value *VisitBinPtrMemD(const Expr *E) { return EmitLoadOfLValue(E); } 366 Value *VisitBinPtrMemI(const Expr *E) { return EmitLoadOfLValue(E); } 367 368 // Other Operators. 369 Value *VisitBlockExpr(const BlockExpr *BE); 370 Value *VisitConditionalOperator(const ConditionalOperator *CO); 371 Value *VisitChooseExpr(ChooseExpr *CE); 372 Value *VisitVAArgExpr(VAArgExpr *VE); 373 Value *VisitObjCStringLiteral(const ObjCStringLiteral *E) { 374 return CGF.EmitObjCStringLiteral(E); 375 } 376}; 377} // end anonymous namespace. 378 379//===----------------------------------------------------------------------===// 380// Utilities 381//===----------------------------------------------------------------------===// 382 383/// EmitConversionToBool - Convert the specified expression value to a 384/// boolean (i1) truth value. This is equivalent to "Val != 0". 385Value *ScalarExprEmitter::EmitConversionToBool(Value *Src, QualType SrcType) { 386 assert(SrcType.isCanonical() && "EmitScalarConversion strips typedefs"); 387 388 if (SrcType->isRealFloatingType()) { 389 // Compare against 0.0 for fp scalars. 390 llvm::Value *Zero = llvm::Constant::getNullValue(Src->getType()); 391 return Builder.CreateFCmpUNE(Src, Zero, "tobool"); 392 } 393 394 if (SrcType->isMemberPointerType()) { 395 // Compare against -1. 396 llvm::Value *NegativeOne = llvm::Constant::getAllOnesValue(Src->getType()); 397 return Builder.CreateICmpNE(Src, NegativeOne, "tobool"); 398 } 399 400 assert((SrcType->isIntegerType() || isa<llvm::PointerType>(Src->getType())) && 401 "Unknown scalar type to convert"); 402 403 // Because of the type rules of C, we often end up computing a logical value, 404 // then zero extending it to int, then wanting it as a logical value again. 405 // Optimize this common case. 406 if (llvm::ZExtInst *ZI = dyn_cast<llvm::ZExtInst>(Src)) { 407 if (ZI->getOperand(0)->getType() == 408 llvm::Type::getInt1Ty(CGF.getLLVMContext())) { 409 Value *Result = ZI->getOperand(0); 410 // If there aren't any more uses, zap the instruction to save space. 411 // Note that there can be more uses, for example if this 412 // is the result of an assignment. 413 if (ZI->use_empty()) 414 ZI->eraseFromParent(); 415 return Result; 416 } 417 } 418 419 // Compare against an integer or pointer null. 420 llvm::Value *Zero = llvm::Constant::getNullValue(Src->getType()); 421 return Builder.CreateICmpNE(Src, Zero, "tobool"); 422} 423 424/// EmitScalarConversion - Emit a conversion from the specified type to the 425/// specified destination type, both of which are LLVM scalar types. 426Value *ScalarExprEmitter::EmitScalarConversion(Value *Src, QualType SrcType, 427 QualType DstType) { 428 SrcType = CGF.getContext().getCanonicalType(SrcType); 429 DstType = CGF.getContext().getCanonicalType(DstType); 430 if (SrcType == DstType) return Src; 431 432 if (DstType->isVoidType()) return 0; 433 434 llvm::LLVMContext &VMContext = CGF.getLLVMContext(); 435 436 // Handle conversions to bool first, they are special: comparisons against 0. 437 if (DstType->isBooleanType()) 438 return EmitConversionToBool(Src, SrcType); 439 440 const llvm::Type *DstTy = ConvertType(DstType); 441 442 // Ignore conversions like int -> uint. 443 if (Src->getType() == DstTy) 444 return Src; 445 446 // Handle pointer conversions next: pointers can only be converted to/from 447 // other pointers and integers. Check for pointer types in terms of LLVM, as 448 // some native types (like Obj-C id) may map to a pointer type. 449 if (isa<llvm::PointerType>(DstTy)) { 450 // The source value may be an integer, or a pointer. 451 if (isa<llvm::PointerType>(Src->getType())) 452 return Builder.CreateBitCast(Src, DstTy, "conv"); 453 454 assert(SrcType->isIntegerType() && "Not ptr->ptr or int->ptr conversion?"); 455 // First, convert to the correct width so that we control the kind of 456 // extension. 457 const llvm::Type *MiddleTy = 458 llvm::IntegerType::get(VMContext, CGF.LLVMPointerWidth); 459 bool InputSigned = SrcType->isSignedIntegerType(); 460 llvm::Value* IntResult = 461 Builder.CreateIntCast(Src, MiddleTy, InputSigned, "conv"); 462 // Then, cast to pointer. 463 return Builder.CreateIntToPtr(IntResult, DstTy, "conv"); 464 } 465 466 if (isa<llvm::PointerType>(Src->getType())) { 467 // Must be an ptr to int cast. 468 assert(isa<llvm::IntegerType>(DstTy) && "not ptr->int?"); 469 return Builder.CreatePtrToInt(Src, DstTy, "conv"); 470 } 471 472 // A scalar can be splatted to an extended vector of the same element type 473 if (DstType->isExtVectorType() && !SrcType->isVectorType()) { 474 // Cast the scalar to element type 475 QualType EltTy = DstType->getAs<ExtVectorType>()->getElementType(); 476 llvm::Value *Elt = EmitScalarConversion(Src, SrcType, EltTy); 477 478 // Insert the element in element zero of an undef vector 479 llvm::Value *UnV = llvm::UndefValue::get(DstTy); 480 llvm::Value *Idx = 481 llvm::ConstantInt::get(llvm::Type::getInt32Ty(VMContext), 0); 482 UnV = Builder.CreateInsertElement(UnV, Elt, Idx, "tmp"); 483 484 // Splat the element across to all elements 485 llvm::SmallVector<llvm::Constant*, 16> Args; 486 unsigned NumElements = cast<llvm::VectorType>(DstTy)->getNumElements(); 487 for (unsigned i = 0; i < NumElements; i++) 488 Args.push_back(llvm::ConstantInt::get( 489 llvm::Type::getInt32Ty(VMContext), 0)); 490 491 llvm::Constant *Mask = llvm::ConstantVector::get(&Args[0], NumElements); 492 llvm::Value *Yay = Builder.CreateShuffleVector(UnV, UnV, Mask, "splat"); 493 return Yay; 494 } 495 496 // Allow bitcast from vector to integer/fp of the same size. 497 if (isa<llvm::VectorType>(Src->getType()) || 498 isa<llvm::VectorType>(DstTy)) 499 return Builder.CreateBitCast(Src, DstTy, "conv"); 500 501 // Finally, we have the arithmetic types: real int/float. 502 if (isa<llvm::IntegerType>(Src->getType())) { 503 bool InputSigned = SrcType->isSignedIntegerType(); 504 if (isa<llvm::IntegerType>(DstTy)) 505 return Builder.CreateIntCast(Src, DstTy, InputSigned, "conv"); 506 else if (InputSigned) 507 return Builder.CreateSIToFP(Src, DstTy, "conv"); 508 else 509 return Builder.CreateUIToFP(Src, DstTy, "conv"); 510 } 511 512 assert(Src->getType()->isFloatingPointTy() && "Unknown real conversion"); 513 if (isa<llvm::IntegerType>(DstTy)) { 514 if (DstType->isSignedIntegerType()) 515 return Builder.CreateFPToSI(Src, DstTy, "conv"); 516 else 517 return Builder.CreateFPToUI(Src, DstTy, "conv"); 518 } 519 520 assert(DstTy->isFloatingPointTy() && "Unknown real conversion"); 521 if (DstTy->getTypeID() < Src->getType()->getTypeID()) 522 return Builder.CreateFPTrunc(Src, DstTy, "conv"); 523 else 524 return Builder.CreateFPExt(Src, DstTy, "conv"); 525} 526 527/// EmitComplexToScalarConversion - Emit a conversion from the specified complex 528/// type to the specified destination type, where the destination type is an 529/// LLVM scalar type. 530Value *ScalarExprEmitter:: 531EmitComplexToScalarConversion(CodeGenFunction::ComplexPairTy Src, 532 QualType SrcTy, QualType DstTy) { 533 // Get the source element type. 534 SrcTy = SrcTy->getAs<ComplexType>()->getElementType(); 535 536 // Handle conversions to bool first, they are special: comparisons against 0. 537 if (DstTy->isBooleanType()) { 538 // Complex != 0 -> (Real != 0) | (Imag != 0) 539 Src.first = EmitScalarConversion(Src.first, SrcTy, DstTy); 540 Src.second = EmitScalarConversion(Src.second, SrcTy, DstTy); 541 return Builder.CreateOr(Src.first, Src.second, "tobool"); 542 } 543 544 // C99 6.3.1.7p2: "When a value of complex type is converted to a real type, 545 // the imaginary part of the complex value is discarded and the value of the 546 // real part is converted according to the conversion rules for the 547 // corresponding real type. 548 return EmitScalarConversion(Src.first, SrcTy, DstTy); 549} 550 551 552//===----------------------------------------------------------------------===// 553// Visitor Methods 554//===----------------------------------------------------------------------===// 555 556Value *ScalarExprEmitter::VisitExpr(Expr *E) { 557 CGF.ErrorUnsupported(E, "scalar expression"); 558 if (E->getType()->isVoidType()) 559 return 0; 560 return llvm::UndefValue::get(CGF.ConvertType(E->getType())); 561} 562 563Value *ScalarExprEmitter::VisitShuffleVectorExpr(ShuffleVectorExpr *E) { 564 llvm::SmallVector<llvm::Constant*, 32> indices; 565 for (unsigned i = 2; i < E->getNumSubExprs(); i++) { 566 indices.push_back(cast<llvm::Constant>(CGF.EmitScalarExpr(E->getExpr(i)))); 567 } 568 Value* V1 = CGF.EmitScalarExpr(E->getExpr(0)); 569 Value* V2 = CGF.EmitScalarExpr(E->getExpr(1)); 570 Value* SV = llvm::ConstantVector::get(indices.begin(), indices.size()); 571 return Builder.CreateShuffleVector(V1, V2, SV, "shuffle"); 572} 573Value *ScalarExprEmitter::VisitMemberExpr(MemberExpr *E) { 574 Expr::EvalResult Result; 575 if (E->Evaluate(Result, CGF.getContext()) && Result.Val.isInt()) { 576 if (E->isArrow()) 577 CGF.EmitScalarExpr(E->getBase()); 578 else 579 EmitLValue(E->getBase()); 580 return llvm::ConstantInt::get(VMContext, Result.Val.getInt()); 581 } 582 return EmitLoadOfLValue(E); 583} 584 585Value *ScalarExprEmitter::VisitArraySubscriptExpr(ArraySubscriptExpr *E) { 586 TestAndClearIgnoreResultAssign(); 587 588 // Emit subscript expressions in rvalue context's. For most cases, this just 589 // loads the lvalue formed by the subscript expr. However, we have to be 590 // careful, because the base of a vector subscript is occasionally an rvalue, 591 // so we can't get it as an lvalue. 592 if (!E->getBase()->getType()->isVectorType()) 593 return EmitLoadOfLValue(E); 594 595 // Handle the vector case. The base must be a vector, the index must be an 596 // integer value. 597 Value *Base = Visit(E->getBase()); 598 Value *Idx = Visit(E->getIdx()); 599 bool IdxSigned = E->getIdx()->getType()->isSignedIntegerType(); 600 Idx = Builder.CreateIntCast(Idx, 601 llvm::Type::getInt32Ty(CGF.getLLVMContext()), 602 IdxSigned, 603 "vecidxcast"); 604 return Builder.CreateExtractElement(Base, Idx, "vecext"); 605} 606 607static llvm::Constant *getMaskElt(llvm::ShuffleVectorInst *SVI, unsigned Idx, 608 unsigned Off, const llvm::Type *I32Ty) { 609 int MV = SVI->getMaskValue(Idx); 610 if (MV == -1) 611 return llvm::UndefValue::get(I32Ty); 612 return llvm::ConstantInt::get(I32Ty, Off+MV); 613} 614 615Value *ScalarExprEmitter::VisitInitListExpr(InitListExpr *E) { 616 bool Ignore = TestAndClearIgnoreResultAssign(); 617 (void)Ignore; 618 assert (Ignore == false && "init list ignored"); 619 unsigned NumInitElements = E->getNumInits(); 620 621 if (E->hadArrayRangeDesignator()) 622 CGF.ErrorUnsupported(E, "GNU array range designator extension"); 623 624 const llvm::VectorType *VType = 625 dyn_cast<llvm::VectorType>(ConvertType(E->getType())); 626 627 // We have a scalar in braces. Just use the first element. 628 if (!VType) 629 return Visit(E->getInit(0)); 630 631 unsigned ResElts = VType->getNumElements(); 632 const llvm::Type *I32Ty = llvm::Type::getInt32Ty(CGF.getLLVMContext()); 633 634 // Loop over initializers collecting the Value for each, and remembering 635 // whether the source was swizzle (ExtVectorElementExpr). This will allow 636 // us to fold the shuffle for the swizzle into the shuffle for the vector 637 // initializer, since LLVM optimizers generally do not want to touch 638 // shuffles. 639 unsigned CurIdx = 0; 640 bool VIsUndefShuffle = false; 641 llvm::Value *V = llvm::UndefValue::get(VType); 642 for (unsigned i = 0; i != NumInitElements; ++i) { 643 Expr *IE = E->getInit(i); 644 Value *Init = Visit(IE); 645 llvm::SmallVector<llvm::Constant*, 16> Args; 646 647 const llvm::VectorType *VVT = dyn_cast<llvm::VectorType>(Init->getType()); 648 649 // Handle scalar elements. If the scalar initializer is actually one 650 // element of a different vector of the same width, use shuffle instead of 651 // extract+insert. 652 if (!VVT) { 653 if (isa<ExtVectorElementExpr>(IE)) { 654 llvm::ExtractElementInst *EI = cast<llvm::ExtractElementInst>(Init); 655 656 if (EI->getVectorOperandType()->getNumElements() == ResElts) { 657 llvm::ConstantInt *C = cast<llvm::ConstantInt>(EI->getIndexOperand()); 658 Value *LHS = 0, *RHS = 0; 659 if (CurIdx == 0) { 660 // insert into undef -> shuffle (src, undef) 661 Args.push_back(C); 662 for (unsigned j = 1; j != ResElts; ++j) 663 Args.push_back(llvm::UndefValue::get(I32Ty)); 664 665 LHS = EI->getVectorOperand(); 666 RHS = V; 667 VIsUndefShuffle = true; 668 } else if (VIsUndefShuffle) { 669 // insert into undefshuffle && size match -> shuffle (v, src) 670 llvm::ShuffleVectorInst *SVV = cast<llvm::ShuffleVectorInst>(V); 671 for (unsigned j = 0; j != CurIdx; ++j) 672 Args.push_back(getMaskElt(SVV, j, 0, I32Ty)); 673 Args.push_back(llvm::ConstantInt::get(I32Ty, 674 ResElts + C->getZExtValue())); 675 for (unsigned j = CurIdx + 1; j != ResElts; ++j) 676 Args.push_back(llvm::UndefValue::get(I32Ty)); 677 678 LHS = cast<llvm::ShuffleVectorInst>(V)->getOperand(0); 679 RHS = EI->getVectorOperand(); 680 VIsUndefShuffle = false; 681 } 682 if (!Args.empty()) { 683 llvm::Constant *Mask = llvm::ConstantVector::get(&Args[0], ResElts); 684 V = Builder.CreateShuffleVector(LHS, RHS, Mask); 685 ++CurIdx; 686 continue; 687 } 688 } 689 } 690 Value *Idx = llvm::ConstantInt::get(I32Ty, CurIdx); 691 V = Builder.CreateInsertElement(V, Init, Idx, "vecinit"); 692 VIsUndefShuffle = false; 693 ++CurIdx; 694 continue; 695 } 696 697 unsigned InitElts = VVT->getNumElements(); 698 699 // If the initializer is an ExtVecEltExpr (a swizzle), and the swizzle's 700 // input is the same width as the vector being constructed, generate an 701 // optimized shuffle of the swizzle input into the result. 702 unsigned Offset = (CurIdx == 0) ? 0 : ResElts; 703 if (isa<ExtVectorElementExpr>(IE)) { 704 llvm::ShuffleVectorInst *SVI = cast<llvm::ShuffleVectorInst>(Init); 705 Value *SVOp = SVI->getOperand(0); 706 const llvm::VectorType *OpTy = cast<llvm::VectorType>(SVOp->getType()); 707 708 if (OpTy->getNumElements() == ResElts) { 709 for (unsigned j = 0; j != CurIdx; ++j) { 710 // If the current vector initializer is a shuffle with undef, merge 711 // this shuffle directly into it. 712 if (VIsUndefShuffle) { 713 Args.push_back(getMaskElt(cast<llvm::ShuffleVectorInst>(V), j, 0, 714 I32Ty)); 715 } else { 716 Args.push_back(llvm::ConstantInt::get(I32Ty, j)); 717 } 718 } 719 for (unsigned j = 0, je = InitElts; j != je; ++j) 720 Args.push_back(getMaskElt(SVI, j, Offset, I32Ty)); 721 for (unsigned j = CurIdx + InitElts; j != ResElts; ++j) 722 Args.push_back(llvm::UndefValue::get(I32Ty)); 723 724 if (VIsUndefShuffle) 725 V = cast<llvm::ShuffleVectorInst>(V)->getOperand(0); 726 727 Init = SVOp; 728 } 729 } 730 731 // Extend init to result vector length, and then shuffle its contribution 732 // to the vector initializer into V. 733 if (Args.empty()) { 734 for (unsigned j = 0; j != InitElts; ++j) 735 Args.push_back(llvm::ConstantInt::get(I32Ty, j)); 736 for (unsigned j = InitElts; j != ResElts; ++j) 737 Args.push_back(llvm::UndefValue::get(I32Ty)); 738 llvm::Constant *Mask = llvm::ConstantVector::get(&Args[0], ResElts); 739 Init = Builder.CreateShuffleVector(Init, llvm::UndefValue::get(VVT), 740 Mask, "vext"); 741 742 Args.clear(); 743 for (unsigned j = 0; j != CurIdx; ++j) 744 Args.push_back(llvm::ConstantInt::get(I32Ty, j)); 745 for (unsigned j = 0; j != InitElts; ++j) 746 Args.push_back(llvm::ConstantInt::get(I32Ty, j+Offset)); 747 for (unsigned j = CurIdx + InitElts; j != ResElts; ++j) 748 Args.push_back(llvm::UndefValue::get(I32Ty)); 749 } 750 751 // If V is undef, make sure it ends up on the RHS of the shuffle to aid 752 // merging subsequent shuffles into this one. 753 if (CurIdx == 0) 754 std::swap(V, Init); 755 llvm::Constant *Mask = llvm::ConstantVector::get(&Args[0], ResElts); 756 V = Builder.CreateShuffleVector(V, Init, Mask, "vecinit"); 757 VIsUndefShuffle = isa<llvm::UndefValue>(Init); 758 CurIdx += InitElts; 759 } 760 761 // FIXME: evaluate codegen vs. shuffling against constant null vector. 762 // Emit remaining default initializers. 763 const llvm::Type *EltTy = VType->getElementType(); 764 765 // Emit remaining default initializers 766 for (/* Do not initialize i*/; CurIdx < ResElts; ++CurIdx) { 767 Value *Idx = llvm::ConstantInt::get(I32Ty, CurIdx); 768 llvm::Value *Init = llvm::Constant::getNullValue(EltTy); 769 V = Builder.CreateInsertElement(V, Init, Idx, "vecinit"); 770 } 771 return V; 772} 773 774static bool ShouldNullCheckClassCastValue(const CastExpr *CE) { 775 const Expr *E = CE->getSubExpr(); 776 777 if (CE->getCastKind() == CastExpr::CK_UncheckedDerivedToBase) 778 return false; 779 780 if (isa<CXXThisExpr>(E)) { 781 // We always assume that 'this' is never null. 782 return false; 783 } 784 785 if (const ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(CE)) { 786 // And that lvalue casts are never null. 787 if (ICE->isLvalueCast()) 788 return false; 789 } 790 791 return true; 792} 793 794// VisitCastExpr - Emit code for an explicit or implicit cast. Implicit casts 795// have to handle a more broad range of conversions than explicit casts, as they 796// handle things like function to ptr-to-function decay etc. 797Value *ScalarExprEmitter::EmitCastExpr(CastExpr *CE) { 798 Expr *E = CE->getSubExpr(); 799 QualType DestTy = CE->getType(); 800 CastExpr::CastKind Kind = CE->getCastKind(); 801 802 if (!DestTy->isVoidType()) 803 TestAndClearIgnoreResultAssign(); 804 805 // Since almost all cast kinds apply to scalars, this switch doesn't have 806 // a default case, so the compiler will warn on a missing case. The cases 807 // are in the same order as in the CastKind enum. 808 switch (Kind) { 809 case CastExpr::CK_Unknown: 810 // FIXME: All casts should have a known kind! 811 //assert(0 && "Unknown cast kind!"); 812 break; 813 814 case CastExpr::CK_AnyPointerToObjCPointerCast: 815 case CastExpr::CK_AnyPointerToBlockPointerCast: 816 case CastExpr::CK_BitCast: { 817 Value *Src = Visit(const_cast<Expr*>(E)); 818 return Builder.CreateBitCast(Src, ConvertType(DestTy)); 819 } 820 case CastExpr::CK_NoOp: 821 case CastExpr::CK_UserDefinedConversion: 822 return Visit(const_cast<Expr*>(E)); 823 824 case CastExpr::CK_BaseToDerived: { 825 const CXXRecordDecl *DerivedClassDecl = 826 DestTy->getCXXRecordDeclForPointerType(); 827 828 return CGF.GetAddressOfDerivedClass(Visit(E), DerivedClassDecl, 829 CE->getBasePath(), 830 ShouldNullCheckClassCastValue(CE)); 831 } 832 case CastExpr::CK_UncheckedDerivedToBase: 833 case CastExpr::CK_DerivedToBase: { 834 const RecordType *DerivedClassTy = 835 E->getType()->getAs<PointerType>()->getPointeeType()->getAs<RecordType>(); 836 CXXRecordDecl *DerivedClassDecl = 837 cast<CXXRecordDecl>(DerivedClassTy->getDecl()); 838 839 return CGF.GetAddressOfBaseClass(Visit(E), DerivedClassDecl, 840 CE->getBasePath(), 841 ShouldNullCheckClassCastValue(CE)); 842 } 843 case CastExpr::CK_Dynamic: { 844 Value *V = Visit(const_cast<Expr*>(E)); 845 const CXXDynamicCastExpr *DCE = cast<CXXDynamicCastExpr>(CE); 846 return CGF.EmitDynamicCast(V, DCE); 847 } 848 case CastExpr::CK_ToUnion: 849 assert(0 && "Should be unreachable!"); 850 break; 851 852 case CastExpr::CK_ArrayToPointerDecay: { 853 assert(E->getType()->isArrayType() && 854 "Array to pointer decay must have array source type!"); 855 856 Value *V = EmitLValue(E).getAddress(); // Bitfields can't be arrays. 857 858 // Note that VLA pointers are always decayed, so we don't need to do 859 // anything here. 860 if (!E->getType()->isVariableArrayType()) { 861 assert(isa<llvm::PointerType>(V->getType()) && "Expected pointer"); 862 assert(isa<llvm::ArrayType>(cast<llvm::PointerType>(V->getType()) 863 ->getElementType()) && 864 "Expected pointer to array"); 865 V = Builder.CreateStructGEP(V, 0, "arraydecay"); 866 } 867 868 return V; 869 } 870 case CastExpr::CK_FunctionToPointerDecay: 871 return EmitLValue(E).getAddress(); 872 873 case CastExpr::CK_NullToMemberPointer: 874 return CGF.CGM.EmitNullConstant(DestTy); 875 876 case CastExpr::CK_BaseToDerivedMemberPointer: 877 case CastExpr::CK_DerivedToBaseMemberPointer: { 878 Value *Src = Visit(E); 879 880 // See if we need to adjust the pointer. 881 const CXXRecordDecl *BaseDecl = 882 cast<CXXRecordDecl>(E->getType()->getAs<MemberPointerType>()-> 883 getClass()->getAs<RecordType>()->getDecl()); 884 const CXXRecordDecl *DerivedDecl = 885 cast<CXXRecordDecl>(CE->getType()->getAs<MemberPointerType>()-> 886 getClass()->getAs<RecordType>()->getDecl()); 887 if (CE->getCastKind() == CastExpr::CK_DerivedToBaseMemberPointer) 888 std::swap(DerivedDecl, BaseDecl); 889 890 if (llvm::Constant *Adj = 891 CGF.CGM.GetNonVirtualBaseClassOffset(DerivedDecl, 892 CE->getBasePath())) { 893 if (CE->getCastKind() == CastExpr::CK_DerivedToBaseMemberPointer) 894 Src = Builder.CreateSub(Src, Adj, "adj"); 895 else 896 Src = Builder.CreateAdd(Src, Adj, "adj"); 897 } 898 return Src; 899 } 900 901 case CastExpr::CK_ConstructorConversion: 902 assert(0 && "Should be unreachable!"); 903 break; 904 905 case CastExpr::CK_IntegralToPointer: { 906 Value *Src = Visit(const_cast<Expr*>(E)); 907 908 // First, convert to the correct width so that we control the kind of 909 // extension. 910 const llvm::Type *MiddleTy = 911 llvm::IntegerType::get(VMContext, CGF.LLVMPointerWidth); 912 bool InputSigned = E->getType()->isSignedIntegerType(); 913 llvm::Value* IntResult = 914 Builder.CreateIntCast(Src, MiddleTy, InputSigned, "conv"); 915 916 return Builder.CreateIntToPtr(IntResult, ConvertType(DestTy)); 917 } 918 case CastExpr::CK_PointerToIntegral: { 919 Value *Src = Visit(const_cast<Expr*>(E)); 920 return Builder.CreatePtrToInt(Src, ConvertType(DestTy)); 921 } 922 case CastExpr::CK_ToVoid: { 923 CGF.EmitAnyExpr(E, 0, false, true); 924 return 0; 925 } 926 case CastExpr::CK_VectorSplat: { 927 const llvm::Type *DstTy = ConvertType(DestTy); 928 Value *Elt = Visit(const_cast<Expr*>(E)); 929 930 // Insert the element in element zero of an undef vector 931 llvm::Value *UnV = llvm::UndefValue::get(DstTy); 932 llvm::Value *Idx = 933 llvm::ConstantInt::get(llvm::Type::getInt32Ty(VMContext), 0); 934 UnV = Builder.CreateInsertElement(UnV, Elt, Idx, "tmp"); 935 936 // Splat the element across to all elements 937 llvm::SmallVector<llvm::Constant*, 16> Args; 938 unsigned NumElements = cast<llvm::VectorType>(DstTy)->getNumElements(); 939 for (unsigned i = 0; i < NumElements; i++) 940 Args.push_back(llvm::ConstantInt::get( 941 llvm::Type::getInt32Ty(VMContext), 0)); 942 943 llvm::Constant *Mask = llvm::ConstantVector::get(&Args[0], NumElements); 944 llvm::Value *Yay = Builder.CreateShuffleVector(UnV, UnV, Mask, "splat"); 945 return Yay; 946 } 947 case CastExpr::CK_IntegralCast: 948 case CastExpr::CK_IntegralToFloating: 949 case CastExpr::CK_FloatingToIntegral: 950 case CastExpr::CK_FloatingCast: 951 return EmitScalarConversion(Visit(E), E->getType(), DestTy); 952 953 case CastExpr::CK_MemberPointerToBoolean: 954 return CGF.EvaluateExprAsBool(E); 955 } 956 957 // Handle cases where the source is an non-complex type. 958 959 if (!CGF.hasAggregateLLVMType(E->getType())) { 960 Value *Src = Visit(const_cast<Expr*>(E)); 961 962 // Use EmitScalarConversion to perform the conversion. 963 return EmitScalarConversion(Src, E->getType(), DestTy); 964 } 965 966 if (E->getType()->isAnyComplexType()) { 967 // Handle cases where the source is a complex type. 968 bool IgnoreImag = true; 969 bool IgnoreImagAssign = true; 970 bool IgnoreReal = IgnoreResultAssign; 971 bool IgnoreRealAssign = IgnoreResultAssign; 972 if (DestTy->isBooleanType()) 973 IgnoreImagAssign = IgnoreImag = false; 974 else if (DestTy->isVoidType()) { 975 IgnoreReal = IgnoreImag = false; 976 IgnoreRealAssign = IgnoreImagAssign = true; 977 } 978 CodeGenFunction::ComplexPairTy V 979 = CGF.EmitComplexExpr(E, IgnoreReal, IgnoreImag, IgnoreRealAssign, 980 IgnoreImagAssign); 981 return EmitComplexToScalarConversion(V, E->getType(), DestTy); 982 } 983 984 // Okay, this is a cast from an aggregate. It must be a cast to void. Just 985 // evaluate the result and return. 986 CGF.EmitAggExpr(E, 0, false, true); 987 return 0; 988} 989 990Value *ScalarExprEmitter::VisitStmtExpr(const StmtExpr *E) { 991 return CGF.EmitCompoundStmt(*E->getSubStmt(), 992 !E->getType()->isVoidType()).getScalarVal(); 993} 994 995Value *ScalarExprEmitter::VisitBlockDeclRefExpr(const BlockDeclRefExpr *E) { 996 llvm::Value *V = CGF.GetAddrOfBlockDecl(E); 997 if (E->getType().isObjCGCWeak()) 998 return CGF.CGM.getObjCRuntime().EmitObjCWeakRead(CGF, V); 999 return Builder.CreateLoad(V, "tmp"); 1000} 1001 1002//===----------------------------------------------------------------------===// 1003// Unary Operators 1004//===----------------------------------------------------------------------===// 1005 1006Value *ScalarExprEmitter::VisitUnaryMinus(const UnaryOperator *E) { 1007 TestAndClearIgnoreResultAssign(); 1008 Value *Op = Visit(E->getSubExpr()); 1009 if (Op->getType()->isFPOrFPVectorTy()) 1010 return Builder.CreateFNeg(Op, "neg"); 1011 return Builder.CreateNeg(Op, "neg"); 1012} 1013 1014Value *ScalarExprEmitter::VisitUnaryNot(const UnaryOperator *E) { 1015 TestAndClearIgnoreResultAssign(); 1016 Value *Op = Visit(E->getSubExpr()); 1017 return Builder.CreateNot(Op, "neg"); 1018} 1019 1020Value *ScalarExprEmitter::VisitUnaryLNot(const UnaryOperator *E) { 1021 // Compare operand to zero. 1022 Value *BoolVal = CGF.EvaluateExprAsBool(E->getSubExpr()); 1023 1024 // Invert value. 1025 // TODO: Could dynamically modify easy computations here. For example, if 1026 // the operand is an icmp ne, turn into icmp eq. 1027 BoolVal = Builder.CreateNot(BoolVal, "lnot"); 1028 1029 // ZExt result to the expr type. 1030 return Builder.CreateZExt(BoolVal, ConvertType(E->getType()), "lnot.ext"); 1031} 1032 1033/// VisitSizeOfAlignOfExpr - Return the size or alignment of the type of 1034/// argument of the sizeof expression as an integer. 1035Value * 1036ScalarExprEmitter::VisitSizeOfAlignOfExpr(const SizeOfAlignOfExpr *E) { 1037 QualType TypeToSize = E->getTypeOfArgument(); 1038 if (E->isSizeOf()) { 1039 if (const VariableArrayType *VAT = 1040 CGF.getContext().getAsVariableArrayType(TypeToSize)) { 1041 if (E->isArgumentType()) { 1042 // sizeof(type) - make sure to emit the VLA size. 1043 CGF.EmitVLASize(TypeToSize); 1044 } else { 1045 // C99 6.5.3.4p2: If the argument is an expression of type 1046 // VLA, it is evaluated. 1047 CGF.EmitAnyExpr(E->getArgumentExpr()); 1048 } 1049 1050 return CGF.GetVLASize(VAT); 1051 } 1052 } 1053 1054 // If this isn't sizeof(vla), the result must be constant; use the constant 1055 // folding logic so we don't have to duplicate it here. 1056 Expr::EvalResult Result; 1057 E->Evaluate(Result, CGF.getContext()); 1058 return llvm::ConstantInt::get(VMContext, Result.Val.getInt()); 1059} 1060 1061Value *ScalarExprEmitter::VisitUnaryReal(const UnaryOperator *E) { 1062 Expr *Op = E->getSubExpr(); 1063 if (Op->getType()->isAnyComplexType()) 1064 return CGF.EmitComplexExpr(Op, false, true, false, true).first; 1065 return Visit(Op); 1066} 1067Value *ScalarExprEmitter::VisitUnaryImag(const UnaryOperator *E) { 1068 Expr *Op = E->getSubExpr(); 1069 if (Op->getType()->isAnyComplexType()) 1070 return CGF.EmitComplexExpr(Op, true, false, true, false).second; 1071 1072 // __imag on a scalar returns zero. Emit the subexpr to ensure side 1073 // effects are evaluated, but not the actual value. 1074 if (E->isLvalue(CGF.getContext()) == Expr::LV_Valid) 1075 CGF.EmitLValue(Op); 1076 else 1077 CGF.EmitScalarExpr(Op, true); 1078 return llvm::Constant::getNullValue(ConvertType(E->getType())); 1079} 1080 1081Value *ScalarExprEmitter::VisitUnaryOffsetOf(const UnaryOperator *E) { 1082 Value* ResultAsPtr = EmitLValue(E->getSubExpr()).getAddress(); 1083 const llvm::Type* ResultType = ConvertType(E->getType()); 1084 return Builder.CreatePtrToInt(ResultAsPtr, ResultType, "offsetof"); 1085} 1086 1087//===----------------------------------------------------------------------===// 1088// Binary Operators 1089//===----------------------------------------------------------------------===// 1090 1091BinOpInfo ScalarExprEmitter::EmitBinOps(const BinaryOperator *E) { 1092 TestAndClearIgnoreResultAssign(); 1093 BinOpInfo Result; 1094 Result.LHS = Visit(E->getLHS()); 1095 Result.RHS = Visit(E->getRHS()); 1096 Result.Ty = E->getType(); 1097 Result.E = E; 1098 return Result; 1099} 1100 1101LValue ScalarExprEmitter::EmitCompoundAssignLValue( 1102 const CompoundAssignOperator *E, 1103 Value *(ScalarExprEmitter::*Func)(const BinOpInfo &), 1104 Value *&BitFieldResult) { 1105 QualType LHSTy = E->getLHS()->getType(); 1106 BitFieldResult = 0; 1107 BinOpInfo OpInfo; 1108 1109 if (E->getComputationResultType()->isAnyComplexType()) { 1110 // This needs to go through the complex expression emitter, but it's a tad 1111 // complicated to do that... I'm leaving it out for now. (Note that we do 1112 // actually need the imaginary part of the RHS for multiplication and 1113 // division.) 1114 CGF.ErrorUnsupported(E, "complex compound assignment"); 1115 llvm::UndefValue::get(CGF.ConvertType(E->getType())); 1116 return LValue(); 1117 } 1118 1119 // Emit the RHS first. __block variables need to have the rhs evaluated 1120 // first, plus this should improve codegen a little. 1121 OpInfo.RHS = Visit(E->getRHS()); 1122 OpInfo.Ty = E->getComputationResultType(); 1123 OpInfo.E = E; 1124 // Load/convert the LHS. 1125 LValue LHSLV = EmitCheckedLValue(E->getLHS()); 1126 OpInfo.LHS = EmitLoadOfLValue(LHSLV, LHSTy); 1127 OpInfo.LHS = EmitScalarConversion(OpInfo.LHS, LHSTy, 1128 E->getComputationLHSType()); 1129 1130 // Expand the binary operator. 1131 Value *Result = (this->*Func)(OpInfo); 1132 1133 // Convert the result back to the LHS type. 1134 Result = EmitScalarConversion(Result, E->getComputationResultType(), LHSTy); 1135 1136 // Store the result value into the LHS lvalue. Bit-fields are handled 1137 // specially because the result is altered by the store, i.e., [C99 6.5.16p1] 1138 // 'An assignment expression has the value of the left operand after the 1139 // assignment...'. 1140 if (LHSLV.isBitField()) { 1141 if (!LHSLV.isVolatileQualified()) { 1142 CGF.EmitStoreThroughBitfieldLValue(RValue::get(Result), LHSLV, LHSTy, 1143 &Result); 1144 BitFieldResult = Result; 1145 return LHSLV; 1146 } else 1147 CGF.EmitStoreThroughBitfieldLValue(RValue::get(Result), LHSLV, LHSTy); 1148 } else 1149 CGF.EmitStoreThroughLValue(RValue::get(Result), LHSLV, LHSTy); 1150 return LHSLV; 1151} 1152 1153Value *ScalarExprEmitter::EmitCompoundAssign(const CompoundAssignOperator *E, 1154 Value *(ScalarExprEmitter::*Func)(const BinOpInfo &)) { 1155 bool Ignore = TestAndClearIgnoreResultAssign(); 1156 Value *BitFieldResult; 1157 LValue LHSLV = EmitCompoundAssignLValue(E, Func, BitFieldResult); 1158 if (BitFieldResult) 1159 return BitFieldResult; 1160 1161 if (Ignore) 1162 return 0; 1163 return EmitLoadOfLValue(LHSLV, E->getType()); 1164} 1165 1166 1167Value *ScalarExprEmitter::EmitDiv(const BinOpInfo &Ops) { 1168 if (Ops.LHS->getType()->isFPOrFPVectorTy()) 1169 return Builder.CreateFDiv(Ops.LHS, Ops.RHS, "div"); 1170 else if (Ops.Ty->isUnsignedIntegerType()) 1171 return Builder.CreateUDiv(Ops.LHS, Ops.RHS, "div"); 1172 else 1173 return Builder.CreateSDiv(Ops.LHS, Ops.RHS, "div"); 1174} 1175 1176Value *ScalarExprEmitter::EmitRem(const BinOpInfo &Ops) { 1177 // Rem in C can't be a floating point type: C99 6.5.5p2. 1178 if (Ops.Ty->isUnsignedIntegerType()) 1179 return Builder.CreateURem(Ops.LHS, Ops.RHS, "rem"); 1180 else 1181 return Builder.CreateSRem(Ops.LHS, Ops.RHS, "rem"); 1182} 1183 1184Value *ScalarExprEmitter::EmitOverflowCheckedBinOp(const BinOpInfo &Ops) { 1185 unsigned IID; 1186 unsigned OpID = 0; 1187 1188 switch (Ops.E->getOpcode()) { 1189 case BinaryOperator::Add: 1190 case BinaryOperator::AddAssign: 1191 OpID = 1; 1192 IID = llvm::Intrinsic::sadd_with_overflow; 1193 break; 1194 case BinaryOperator::Sub: 1195 case BinaryOperator::SubAssign: 1196 OpID = 2; 1197 IID = llvm::Intrinsic::ssub_with_overflow; 1198 break; 1199 case BinaryOperator::Mul: 1200 case BinaryOperator::MulAssign: 1201 OpID = 3; 1202 IID = llvm::Intrinsic::smul_with_overflow; 1203 break; 1204 default: 1205 assert(false && "Unsupported operation for overflow detection"); 1206 IID = 0; 1207 } 1208 OpID <<= 1; 1209 OpID |= 1; 1210 1211 const llvm::Type *opTy = CGF.CGM.getTypes().ConvertType(Ops.Ty); 1212 1213 llvm::Function *intrinsic = CGF.CGM.getIntrinsic(IID, &opTy, 1); 1214 1215 Value *resultAndOverflow = Builder.CreateCall2(intrinsic, Ops.LHS, Ops.RHS); 1216 Value *result = Builder.CreateExtractValue(resultAndOverflow, 0); 1217 Value *overflow = Builder.CreateExtractValue(resultAndOverflow, 1); 1218 1219 // Branch in case of overflow. 1220 llvm::BasicBlock *initialBB = Builder.GetInsertBlock(); 1221 llvm::BasicBlock *overflowBB = 1222 CGF.createBasicBlock("overflow", CGF.CurFn); 1223 llvm::BasicBlock *continueBB = 1224 CGF.createBasicBlock("overflow.continue", CGF.CurFn); 1225 1226 Builder.CreateCondBr(overflow, overflowBB, continueBB); 1227 1228 // Handle overflow 1229 1230 Builder.SetInsertPoint(overflowBB); 1231 1232 // Handler is: 1233 // long long *__overflow_handler)(long long a, long long b, char op, 1234 // char width) 1235 std::vector<const llvm::Type*> handerArgTypes; 1236 handerArgTypes.push_back(llvm::Type::getInt64Ty(VMContext)); 1237 handerArgTypes.push_back(llvm::Type::getInt64Ty(VMContext)); 1238 handerArgTypes.push_back(llvm::Type::getInt8Ty(VMContext)); 1239 handerArgTypes.push_back(llvm::Type::getInt8Ty(VMContext)); 1240 llvm::FunctionType *handlerTy = llvm::FunctionType::get( 1241 llvm::Type::getInt64Ty(VMContext), handerArgTypes, false); 1242 llvm::Value *handlerFunction = 1243 CGF.CGM.getModule().getOrInsertGlobal("__overflow_handler", 1244 llvm::PointerType::getUnqual(handlerTy)); 1245 handlerFunction = Builder.CreateLoad(handlerFunction); 1246 1247 llvm::Value *handlerResult = Builder.CreateCall4(handlerFunction, 1248 Builder.CreateSExt(Ops.LHS, llvm::Type::getInt64Ty(VMContext)), 1249 Builder.CreateSExt(Ops.RHS, llvm::Type::getInt64Ty(VMContext)), 1250 llvm::ConstantInt::get(llvm::Type::getInt8Ty(VMContext), OpID), 1251 llvm::ConstantInt::get(llvm::Type::getInt8Ty(VMContext), 1252 cast<llvm::IntegerType>(opTy)->getBitWidth())); 1253 1254 handlerResult = Builder.CreateTrunc(handlerResult, opTy); 1255 1256 Builder.CreateBr(continueBB); 1257 1258 // Set up the continuation 1259 Builder.SetInsertPoint(continueBB); 1260 // Get the correct result 1261 llvm::PHINode *phi = Builder.CreatePHI(opTy); 1262 phi->reserveOperandSpace(2); 1263 phi->addIncoming(result, initialBB); 1264 phi->addIncoming(handlerResult, overflowBB); 1265 1266 return phi; 1267} 1268 1269Value *ScalarExprEmitter::EmitAdd(const BinOpInfo &Ops) { 1270 if (!Ops.Ty->isAnyPointerType()) { 1271 if (CGF.getContext().getLangOptions().OverflowChecking && 1272 Ops.Ty->isSignedIntegerType()) 1273 return EmitOverflowCheckedBinOp(Ops); 1274 1275 if (Ops.LHS->getType()->isFPOrFPVectorTy()) 1276 return Builder.CreateFAdd(Ops.LHS, Ops.RHS, "add"); 1277 1278 // Signed integer overflow is undefined behavior. 1279 if (Ops.Ty->isSignedIntegerType()) 1280 return Builder.CreateNSWAdd(Ops.LHS, Ops.RHS, "add"); 1281 1282 return Builder.CreateAdd(Ops.LHS, Ops.RHS, "add"); 1283 } 1284 1285 if (Ops.Ty->isPointerType() && 1286 Ops.Ty->getAs<PointerType>()->isVariableArrayType()) { 1287 // The amount of the addition needs to account for the VLA size 1288 CGF.ErrorUnsupported(Ops.E, "VLA pointer addition"); 1289 } 1290 Value *Ptr, *Idx; 1291 Expr *IdxExp; 1292 const PointerType *PT = Ops.E->getLHS()->getType()->getAs<PointerType>(); 1293 const ObjCObjectPointerType *OPT = 1294 Ops.E->getLHS()->getType()->getAs<ObjCObjectPointerType>(); 1295 if (PT || OPT) { 1296 Ptr = Ops.LHS; 1297 Idx = Ops.RHS; 1298 IdxExp = Ops.E->getRHS(); 1299 } else { // int + pointer 1300 PT = Ops.E->getRHS()->getType()->getAs<PointerType>(); 1301 OPT = Ops.E->getRHS()->getType()->getAs<ObjCObjectPointerType>(); 1302 assert((PT || OPT) && "Invalid add expr"); 1303 Ptr = Ops.RHS; 1304 Idx = Ops.LHS; 1305 IdxExp = Ops.E->getLHS(); 1306 } 1307 1308 unsigned Width = cast<llvm::IntegerType>(Idx->getType())->getBitWidth(); 1309 if (Width < CGF.LLVMPointerWidth) { 1310 // Zero or sign extend the pointer value based on whether the index is 1311 // signed or not. 1312 const llvm::Type *IdxType = 1313 llvm::IntegerType::get(VMContext, CGF.LLVMPointerWidth); 1314 if (IdxExp->getType()->isSignedIntegerType()) 1315 Idx = Builder.CreateSExt(Idx, IdxType, "idx.ext"); 1316 else 1317 Idx = Builder.CreateZExt(Idx, IdxType, "idx.ext"); 1318 } 1319 const QualType ElementType = PT ? PT->getPointeeType() : OPT->getPointeeType(); 1320 // Handle interface types, which are not represented with a concrete type. 1321 if (const ObjCInterfaceType *OIT = dyn_cast<ObjCInterfaceType>(ElementType)) { 1322 llvm::Value *InterfaceSize = 1323 llvm::ConstantInt::get(Idx->getType(), 1324 CGF.getContext().getTypeSizeInChars(OIT).getQuantity()); 1325 Idx = Builder.CreateMul(Idx, InterfaceSize); 1326 const llvm::Type *i8Ty = llvm::Type::getInt8PtrTy(VMContext); 1327 Value *Casted = Builder.CreateBitCast(Ptr, i8Ty); 1328 Value *Res = Builder.CreateGEP(Casted, Idx, "add.ptr"); 1329 return Builder.CreateBitCast(Res, Ptr->getType()); 1330 } 1331 1332 // Explicitly handle GNU void* and function pointer arithmetic extensions. The 1333 // GNU void* casts amount to no-ops since our void* type is i8*, but this is 1334 // future proof. 1335 if (ElementType->isVoidType() || ElementType->isFunctionType()) { 1336 const llvm::Type *i8Ty = llvm::Type::getInt8PtrTy(VMContext); 1337 Value *Casted = Builder.CreateBitCast(Ptr, i8Ty); 1338 Value *Res = Builder.CreateGEP(Casted, Idx, "add.ptr"); 1339 return Builder.CreateBitCast(Res, Ptr->getType()); 1340 } 1341 1342 return Builder.CreateInBoundsGEP(Ptr, Idx, "add.ptr"); 1343} 1344 1345Value *ScalarExprEmitter::EmitSub(const BinOpInfo &Ops) { 1346 if (!isa<llvm::PointerType>(Ops.LHS->getType())) { 1347 if (CGF.getContext().getLangOptions().OverflowChecking 1348 && Ops.Ty->isSignedIntegerType()) 1349 return EmitOverflowCheckedBinOp(Ops); 1350 1351 if (Ops.LHS->getType()->isFPOrFPVectorTy()) 1352 return Builder.CreateFSub(Ops.LHS, Ops.RHS, "sub"); 1353 1354 // Signed integer overflow is undefined behavior. 1355 if (Ops.Ty->isSignedIntegerType()) 1356 return Builder.CreateNSWSub(Ops.LHS, Ops.RHS, "sub"); 1357 1358 return Builder.CreateSub(Ops.LHS, Ops.RHS, "sub"); 1359 } 1360 1361 if (Ops.E->getLHS()->getType()->isPointerType() && 1362 Ops.E->getLHS()->getType()->getAs<PointerType>()->isVariableArrayType()) { 1363 // The amount of the addition needs to account for the VLA size for 1364 // ptr-int 1365 // The amount of the division needs to account for the VLA size for 1366 // ptr-ptr. 1367 CGF.ErrorUnsupported(Ops.E, "VLA pointer subtraction"); 1368 } 1369 1370 const QualType LHSType = Ops.E->getLHS()->getType(); 1371 const QualType LHSElementType = LHSType->getPointeeType(); 1372 if (!isa<llvm::PointerType>(Ops.RHS->getType())) { 1373 // pointer - int 1374 Value *Idx = Ops.RHS; 1375 unsigned Width = cast<llvm::IntegerType>(Idx->getType())->getBitWidth(); 1376 if (Width < CGF.LLVMPointerWidth) { 1377 // Zero or sign extend the pointer value based on whether the index is 1378 // signed or not. 1379 const llvm::Type *IdxType = 1380 llvm::IntegerType::get(VMContext, CGF.LLVMPointerWidth); 1381 if (Ops.E->getRHS()->getType()->isSignedIntegerType()) 1382 Idx = Builder.CreateSExt(Idx, IdxType, "idx.ext"); 1383 else 1384 Idx = Builder.CreateZExt(Idx, IdxType, "idx.ext"); 1385 } 1386 Idx = Builder.CreateNeg(Idx, "sub.ptr.neg"); 1387 1388 // Handle interface types, which are not represented with a concrete type. 1389 if (const ObjCInterfaceType *OIT = 1390 dyn_cast<ObjCInterfaceType>(LHSElementType)) { 1391 llvm::Value *InterfaceSize = 1392 llvm::ConstantInt::get(Idx->getType(), 1393 CGF.getContext(). 1394 getTypeSizeInChars(OIT).getQuantity()); 1395 Idx = Builder.CreateMul(Idx, InterfaceSize); 1396 const llvm::Type *i8Ty = llvm::Type::getInt8PtrTy(VMContext); 1397 Value *LHSCasted = Builder.CreateBitCast(Ops.LHS, i8Ty); 1398 Value *Res = Builder.CreateGEP(LHSCasted, Idx, "add.ptr"); 1399 return Builder.CreateBitCast(Res, Ops.LHS->getType()); 1400 } 1401 1402 // Explicitly handle GNU void* and function pointer arithmetic 1403 // extensions. The GNU void* casts amount to no-ops since our void* type is 1404 // i8*, but this is future proof. 1405 if (LHSElementType->isVoidType() || LHSElementType->isFunctionType()) { 1406 const llvm::Type *i8Ty = llvm::Type::getInt8PtrTy(VMContext); 1407 Value *LHSCasted = Builder.CreateBitCast(Ops.LHS, i8Ty); 1408 Value *Res = Builder.CreateGEP(LHSCasted, Idx, "sub.ptr"); 1409 return Builder.CreateBitCast(Res, Ops.LHS->getType()); 1410 } 1411 1412 return Builder.CreateInBoundsGEP(Ops.LHS, Idx, "sub.ptr"); 1413 } else { 1414 // pointer - pointer 1415 Value *LHS = Ops.LHS; 1416 Value *RHS = Ops.RHS; 1417 1418 CharUnits ElementSize; 1419 1420 // Handle GCC extension for pointer arithmetic on void* and function pointer 1421 // types. 1422 if (LHSElementType->isVoidType() || LHSElementType->isFunctionType()) { 1423 ElementSize = CharUnits::One(); 1424 } else { 1425 ElementSize = CGF.getContext().getTypeSizeInChars(LHSElementType); 1426 } 1427 1428 const llvm::Type *ResultType = ConvertType(Ops.Ty); 1429 LHS = Builder.CreatePtrToInt(LHS, ResultType, "sub.ptr.lhs.cast"); 1430 RHS = Builder.CreatePtrToInt(RHS, ResultType, "sub.ptr.rhs.cast"); 1431 Value *BytesBetween = Builder.CreateSub(LHS, RHS, "sub.ptr.sub"); 1432 1433 // Optimize out the shift for element size of 1. 1434 if (ElementSize.isOne()) 1435 return BytesBetween; 1436 1437 // Otherwise, do a full sdiv. This uses the "exact" form of sdiv, since 1438 // pointer difference in C is only defined in the case where both operands 1439 // are pointing to elements of an array. 1440 Value *BytesPerElt = 1441 llvm::ConstantInt::get(ResultType, ElementSize.getQuantity()); 1442 return Builder.CreateExactSDiv(BytesBetween, BytesPerElt, "sub.ptr.div"); 1443 } 1444} 1445 1446Value *ScalarExprEmitter::EmitShl(const BinOpInfo &Ops) { 1447 // LLVM requires the LHS and RHS to be the same type: promote or truncate the 1448 // RHS to the same size as the LHS. 1449 Value *RHS = Ops.RHS; 1450 if (Ops.LHS->getType() != RHS->getType()) 1451 RHS = Builder.CreateIntCast(RHS, Ops.LHS->getType(), false, "sh_prom"); 1452 1453 if (CGF.CatchUndefined 1454 && isa<llvm::IntegerType>(Ops.LHS->getType())) { 1455 unsigned Width = cast<llvm::IntegerType>(Ops.LHS->getType())->getBitWidth(); 1456 llvm::BasicBlock *Cont = CGF.createBasicBlock("cont"); 1457 CGF.Builder.CreateCondBr(Builder.CreateICmpULT(RHS, 1458 llvm::ConstantInt::get(RHS->getType(), Width)), 1459 Cont, CGF.getTrapBB()); 1460 CGF.EmitBlock(Cont); 1461 } 1462 1463 return Builder.CreateShl(Ops.LHS, RHS, "shl"); 1464} 1465 1466Value *ScalarExprEmitter::EmitShr(const BinOpInfo &Ops) { 1467 // LLVM requires the LHS and RHS to be the same type: promote or truncate the 1468 // RHS to the same size as the LHS. 1469 Value *RHS = Ops.RHS; 1470 if (Ops.LHS->getType() != RHS->getType()) 1471 RHS = Builder.CreateIntCast(RHS, Ops.LHS->getType(), false, "sh_prom"); 1472 1473 if (CGF.CatchUndefined 1474 && isa<llvm::IntegerType>(Ops.LHS->getType())) { 1475 unsigned Width = cast<llvm::IntegerType>(Ops.LHS->getType())->getBitWidth(); 1476 llvm::BasicBlock *Cont = CGF.createBasicBlock("cont"); 1477 CGF.Builder.CreateCondBr(Builder.CreateICmpULT(RHS, 1478 llvm::ConstantInt::get(RHS->getType(), Width)), 1479 Cont, CGF.getTrapBB()); 1480 CGF.EmitBlock(Cont); 1481 } 1482 1483 if (Ops.Ty->isUnsignedIntegerType()) 1484 return Builder.CreateLShr(Ops.LHS, RHS, "shr"); 1485 return Builder.CreateAShr(Ops.LHS, RHS, "shr"); 1486} 1487 1488Value *ScalarExprEmitter::EmitCompare(const BinaryOperator *E,unsigned UICmpOpc, 1489 unsigned SICmpOpc, unsigned FCmpOpc) { 1490 TestAndClearIgnoreResultAssign(); 1491 Value *Result; 1492 QualType LHSTy = E->getLHS()->getType(); 1493 if (LHSTy->isMemberFunctionPointerType()) { 1494 Value *LHSPtr = CGF.EmitAnyExprToTemp(E->getLHS()).getAggregateAddr(); 1495 Value *RHSPtr = CGF.EmitAnyExprToTemp(E->getRHS()).getAggregateAddr(); 1496 llvm::Value *LHSFunc = Builder.CreateStructGEP(LHSPtr, 0); 1497 LHSFunc = Builder.CreateLoad(LHSFunc); 1498 llvm::Value *RHSFunc = Builder.CreateStructGEP(RHSPtr, 0); 1499 RHSFunc = Builder.CreateLoad(RHSFunc); 1500 Value *ResultF = Builder.CreateICmp((llvm::ICmpInst::Predicate)UICmpOpc, 1501 LHSFunc, RHSFunc, "cmp.func"); 1502 Value *NullPtr = llvm::Constant::getNullValue(LHSFunc->getType()); 1503 Value *ResultNull = Builder.CreateICmp((llvm::ICmpInst::Predicate)UICmpOpc, 1504 LHSFunc, NullPtr, "cmp.null"); 1505 llvm::Value *LHSAdj = Builder.CreateStructGEP(LHSPtr, 1); 1506 LHSAdj = Builder.CreateLoad(LHSAdj); 1507 llvm::Value *RHSAdj = Builder.CreateStructGEP(RHSPtr, 1); 1508 RHSAdj = Builder.CreateLoad(RHSAdj); 1509 Value *ResultA = Builder.CreateICmp((llvm::ICmpInst::Predicate)UICmpOpc, 1510 LHSAdj, RHSAdj, "cmp.adj"); 1511 if (E->getOpcode() == BinaryOperator::EQ) { 1512 Result = Builder.CreateOr(ResultNull, ResultA, "or.na"); 1513 Result = Builder.CreateAnd(Result, ResultF, "and.f"); 1514 } else { 1515 assert(E->getOpcode() == BinaryOperator::NE && 1516 "Member pointer comparison other than == or != ?"); 1517 Result = Builder.CreateAnd(ResultNull, ResultA, "and.na"); 1518 Result = Builder.CreateOr(Result, ResultF, "or.f"); 1519 } 1520 } else if (!LHSTy->isAnyComplexType()) { 1521 Value *LHS = Visit(E->getLHS()); 1522 Value *RHS = Visit(E->getRHS()); 1523 1524 if (LHS->getType()->isFPOrFPVectorTy()) { 1525 Result = Builder.CreateFCmp((llvm::CmpInst::Predicate)FCmpOpc, 1526 LHS, RHS, "cmp"); 1527 } else if (LHSTy->isSignedIntegerType()) { 1528 Result = Builder.CreateICmp((llvm::ICmpInst::Predicate)SICmpOpc, 1529 LHS, RHS, "cmp"); 1530 } else { 1531 // Unsigned integers and pointers. 1532 Result = Builder.CreateICmp((llvm::ICmpInst::Predicate)UICmpOpc, 1533 LHS, RHS, "cmp"); 1534 } 1535 1536 // If this is a vector comparison, sign extend the result to the appropriate 1537 // vector integer type and return it (don't convert to bool). 1538 if (LHSTy->isVectorType()) 1539 return Builder.CreateSExt(Result, ConvertType(E->getType()), "sext"); 1540 1541 } else { 1542 // Complex Comparison: can only be an equality comparison. 1543 CodeGenFunction::ComplexPairTy LHS = CGF.EmitComplexExpr(E->getLHS()); 1544 CodeGenFunction::ComplexPairTy RHS = CGF.EmitComplexExpr(E->getRHS()); 1545 1546 QualType CETy = LHSTy->getAs<ComplexType>()->getElementType(); 1547 1548 Value *ResultR, *ResultI; 1549 if (CETy->isRealFloatingType()) { 1550 ResultR = Builder.CreateFCmp((llvm::FCmpInst::Predicate)FCmpOpc, 1551 LHS.first, RHS.first, "cmp.r"); 1552 ResultI = Builder.CreateFCmp((llvm::FCmpInst::Predicate)FCmpOpc, 1553 LHS.second, RHS.second, "cmp.i"); 1554 } else { 1555 // Complex comparisons can only be equality comparisons. As such, signed 1556 // and unsigned opcodes are the same. 1557 ResultR = Builder.CreateICmp((llvm::ICmpInst::Predicate)UICmpOpc, 1558 LHS.first, RHS.first, "cmp.r"); 1559 ResultI = Builder.CreateICmp((llvm::ICmpInst::Predicate)UICmpOpc, 1560 LHS.second, RHS.second, "cmp.i"); 1561 } 1562 1563 if (E->getOpcode() == BinaryOperator::EQ) { 1564 Result = Builder.CreateAnd(ResultR, ResultI, "and.ri"); 1565 } else { 1566 assert(E->getOpcode() == BinaryOperator::NE && 1567 "Complex comparison other than == or != ?"); 1568 Result = Builder.CreateOr(ResultR, ResultI, "or.ri"); 1569 } 1570 } 1571 1572 return EmitScalarConversion(Result, CGF.getContext().BoolTy, E->getType()); 1573} 1574 1575Value *ScalarExprEmitter::VisitBinAssign(const BinaryOperator *E) { 1576 bool Ignore = TestAndClearIgnoreResultAssign(); 1577 1578 // __block variables need to have the rhs evaluated first, plus this should 1579 // improve codegen just a little. 1580 Value *RHS = Visit(E->getRHS()); 1581 LValue LHS = EmitCheckedLValue(E->getLHS()); 1582 1583 // Store the value into the LHS. Bit-fields are handled specially 1584 // because the result is altered by the store, i.e., [C99 6.5.16p1] 1585 // 'An assignment expression has the value of the left operand after 1586 // the assignment...'. 1587 if (LHS.isBitField()) { 1588 if (!LHS.isVolatileQualified()) { 1589 CGF.EmitStoreThroughBitfieldLValue(RValue::get(RHS), LHS, E->getType(), 1590 &RHS); 1591 return RHS; 1592 } else 1593 CGF.EmitStoreThroughBitfieldLValue(RValue::get(RHS), LHS, E->getType()); 1594 } else 1595 CGF.EmitStoreThroughLValue(RValue::get(RHS), LHS, E->getType()); 1596 if (Ignore) 1597 return 0; 1598 return EmitLoadOfLValue(LHS, E->getType()); 1599} 1600 1601Value *ScalarExprEmitter::VisitBinLAnd(const BinaryOperator *E) { 1602 const llvm::Type *ResTy = ConvertType(E->getType()); 1603 1604 // If we have 0 && RHS, see if we can elide RHS, if so, just return 0. 1605 // If we have 1 && X, just emit X without inserting the control flow. 1606 if (int Cond = CGF.ConstantFoldsToSimpleInteger(E->getLHS())) { 1607 if (Cond == 1) { // If we have 1 && X, just emit X. 1608 Value *RHSCond = CGF.EvaluateExprAsBool(E->getRHS()); 1609 // ZExt result to int or bool. 1610 return Builder.CreateZExtOrBitCast(RHSCond, ResTy, "land.ext"); 1611 } 1612 1613 // 0 && RHS: If it is safe, just elide the RHS, and return 0/false. 1614 if (!CGF.ContainsLabel(E->getRHS())) 1615 return llvm::Constant::getNullValue(ResTy); 1616 } 1617 1618 llvm::BasicBlock *ContBlock = CGF.createBasicBlock("land.end"); 1619 llvm::BasicBlock *RHSBlock = CGF.createBasicBlock("land.rhs"); 1620 1621 // Branch on the LHS first. If it is false, go to the failure (cont) block. 1622 CGF.EmitBranchOnBoolExpr(E->getLHS(), RHSBlock, ContBlock); 1623 1624 // Any edges into the ContBlock are now from an (indeterminate number of) 1625 // edges from this first condition. All of these values will be false. Start 1626 // setting up the PHI node in the Cont Block for this. 1627 llvm::PHINode *PN = llvm::PHINode::Create(llvm::Type::getInt1Ty(VMContext), 1628 "", ContBlock); 1629 PN->reserveOperandSpace(2); // Normal case, two inputs. 1630 for (llvm::pred_iterator PI = pred_begin(ContBlock), PE = pred_end(ContBlock); 1631 PI != PE; ++PI) 1632 PN->addIncoming(llvm::ConstantInt::getFalse(VMContext), *PI); 1633 1634 CGF.BeginConditionalBranch(); 1635 CGF.EmitBlock(RHSBlock); 1636 Value *RHSCond = CGF.EvaluateExprAsBool(E->getRHS()); 1637 CGF.EndConditionalBranch(); 1638 1639 // Reaquire the RHS block, as there may be subblocks inserted. 1640 RHSBlock = Builder.GetInsertBlock(); 1641 1642 // Emit an unconditional branch from this block to ContBlock. Insert an entry 1643 // into the phi node for the edge with the value of RHSCond. 1644 CGF.EmitBlock(ContBlock); 1645 PN->addIncoming(RHSCond, RHSBlock); 1646 1647 // ZExt result to int. 1648 return Builder.CreateZExtOrBitCast(PN, ResTy, "land.ext"); 1649} 1650 1651Value *ScalarExprEmitter::VisitBinLOr(const BinaryOperator *E) { 1652 const llvm::Type *ResTy = ConvertType(E->getType()); 1653 1654 // If we have 1 || RHS, see if we can elide RHS, if so, just return 1. 1655 // If we have 0 || X, just emit X without inserting the control flow. 1656 if (int Cond = CGF.ConstantFoldsToSimpleInteger(E->getLHS())) { 1657 if (Cond == -1) { // If we have 0 || X, just emit X. 1658 Value *RHSCond = CGF.EvaluateExprAsBool(E->getRHS()); 1659 // ZExt result to int or bool. 1660 return Builder.CreateZExtOrBitCast(RHSCond, ResTy, "lor.ext"); 1661 } 1662 1663 // 1 || RHS: If it is safe, just elide the RHS, and return 1/true. 1664 if (!CGF.ContainsLabel(E->getRHS())) 1665 return llvm::ConstantInt::get(ResTy, 1); 1666 } 1667 1668 llvm::BasicBlock *ContBlock = CGF.createBasicBlock("lor.end"); 1669 llvm::BasicBlock *RHSBlock = CGF.createBasicBlock("lor.rhs"); 1670 1671 // Branch on the LHS first. If it is true, go to the success (cont) block. 1672 CGF.EmitBranchOnBoolExpr(E->getLHS(), ContBlock, RHSBlock); 1673 1674 // Any edges into the ContBlock are now from an (indeterminate number of) 1675 // edges from this first condition. All of these values will be true. Start 1676 // setting up the PHI node in the Cont Block for this. 1677 llvm::PHINode *PN = llvm::PHINode::Create(llvm::Type::getInt1Ty(VMContext), 1678 "", ContBlock); 1679 PN->reserveOperandSpace(2); // Normal case, two inputs. 1680 for (llvm::pred_iterator PI = pred_begin(ContBlock), PE = pred_end(ContBlock); 1681 PI != PE; ++PI) 1682 PN->addIncoming(llvm::ConstantInt::getTrue(VMContext), *PI); 1683 1684 CGF.BeginConditionalBranch(); 1685 1686 // Emit the RHS condition as a bool value. 1687 CGF.EmitBlock(RHSBlock); 1688 Value *RHSCond = CGF.EvaluateExprAsBool(E->getRHS()); 1689 1690 CGF.EndConditionalBranch(); 1691 1692 // Reaquire the RHS block, as there may be subblocks inserted. 1693 RHSBlock = Builder.GetInsertBlock(); 1694 1695 // Emit an unconditional branch from this block to ContBlock. Insert an entry 1696 // into the phi node for the edge with the value of RHSCond. 1697 CGF.EmitBlock(ContBlock); 1698 PN->addIncoming(RHSCond, RHSBlock); 1699 1700 // ZExt result to int. 1701 return Builder.CreateZExtOrBitCast(PN, ResTy, "lor.ext"); 1702} 1703 1704Value *ScalarExprEmitter::VisitBinComma(const BinaryOperator *E) { 1705 CGF.EmitStmt(E->getLHS()); 1706 CGF.EnsureInsertPoint(); 1707 return Visit(E->getRHS()); 1708} 1709 1710//===----------------------------------------------------------------------===// 1711// Other Operators 1712//===----------------------------------------------------------------------===// 1713 1714/// isCheapEnoughToEvaluateUnconditionally - Return true if the specified 1715/// expression is cheap enough and side-effect-free enough to evaluate 1716/// unconditionally instead of conditionally. This is used to convert control 1717/// flow into selects in some cases. 1718static bool isCheapEnoughToEvaluateUnconditionally(const Expr *E, 1719 CodeGenFunction &CGF) { 1720 if (const ParenExpr *PE = dyn_cast<ParenExpr>(E)) 1721 return isCheapEnoughToEvaluateUnconditionally(PE->getSubExpr(), CGF); 1722 1723 // TODO: Allow anything we can constant fold to an integer or fp constant. 1724 if (isa<IntegerLiteral>(E) || isa<CharacterLiteral>(E) || 1725 isa<FloatingLiteral>(E)) 1726 return true; 1727 1728 // Non-volatile automatic variables too, to get "cond ? X : Y" where 1729 // X and Y are local variables. 1730 if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(E)) 1731 if (const VarDecl *VD = dyn_cast<VarDecl>(DRE->getDecl())) 1732 if (VD->hasLocalStorage() && !(CGF.getContext() 1733 .getCanonicalType(VD->getType()) 1734 .isVolatileQualified())) 1735 return true; 1736 1737 return false; 1738} 1739 1740 1741Value *ScalarExprEmitter:: 1742VisitConditionalOperator(const ConditionalOperator *E) { 1743 TestAndClearIgnoreResultAssign(); 1744 // If the condition constant folds and can be elided, try to avoid emitting 1745 // the condition and the dead arm. 1746 if (int Cond = CGF.ConstantFoldsToSimpleInteger(E->getCond())){ 1747 Expr *Live = E->getLHS(), *Dead = E->getRHS(); 1748 if (Cond == -1) 1749 std::swap(Live, Dead); 1750 1751 // If the dead side doesn't have labels we need, and if the Live side isn't 1752 // the gnu missing ?: extension (which we could handle, but don't bother 1753 // to), just emit the Live part. 1754 if ((!Dead || !CGF.ContainsLabel(Dead)) && // No labels in dead part 1755 Live) // Live part isn't missing. 1756 return Visit(Live); 1757 } 1758 1759 1760 // If this is a really simple expression (like x ? 4 : 5), emit this as a 1761 // select instead of as control flow. We can only do this if it is cheap and 1762 // safe to evaluate the LHS and RHS unconditionally. 1763 if (E->getLHS() && isCheapEnoughToEvaluateUnconditionally(E->getLHS(), 1764 CGF) && 1765 isCheapEnoughToEvaluateUnconditionally(E->getRHS(), CGF)) { 1766 llvm::Value *CondV = CGF.EvaluateExprAsBool(E->getCond()); 1767 llvm::Value *LHS = Visit(E->getLHS()); 1768 llvm::Value *RHS = Visit(E->getRHS()); 1769 return Builder.CreateSelect(CondV, LHS, RHS, "cond"); 1770 } 1771 1772 1773 llvm::BasicBlock *LHSBlock = CGF.createBasicBlock("cond.true"); 1774 llvm::BasicBlock *RHSBlock = CGF.createBasicBlock("cond.false"); 1775 llvm::BasicBlock *ContBlock = CGF.createBasicBlock("cond.end"); 1776 Value *CondVal = 0; 1777 1778 // If we don't have the GNU missing condition extension, emit a branch on bool 1779 // the normal way. 1780 if (E->getLHS()) { 1781 // Otherwise, just use EmitBranchOnBoolExpr to get small and simple code for 1782 // the branch on bool. 1783 CGF.EmitBranchOnBoolExpr(E->getCond(), LHSBlock, RHSBlock); 1784 } else { 1785 // Otherwise, for the ?: extension, evaluate the conditional and then 1786 // convert it to bool the hard way. We do this explicitly because we need 1787 // the unconverted value for the missing middle value of the ?:. 1788 CondVal = CGF.EmitScalarExpr(E->getCond()); 1789 1790 // In some cases, EmitScalarConversion will delete the "CondVal" expression 1791 // if there are no extra uses (an optimization). Inhibit this by making an 1792 // extra dead use, because we're going to add a use of CondVal later. We 1793 // don't use the builder for this, because we don't want it to get optimized 1794 // away. This leaves dead code, but the ?: extension isn't common. 1795 new llvm::BitCastInst(CondVal, CondVal->getType(), "dummy?:holder", 1796 Builder.GetInsertBlock()); 1797 1798 Value *CondBoolVal = 1799 CGF.EmitScalarConversion(CondVal, E->getCond()->getType(), 1800 CGF.getContext().BoolTy); 1801 Builder.CreateCondBr(CondBoolVal, LHSBlock, RHSBlock); 1802 } 1803 1804 CGF.BeginConditionalBranch(); 1805 CGF.EmitBlock(LHSBlock); 1806 1807 // Handle the GNU extension for missing LHS. 1808 Value *LHS; 1809 if (E->getLHS()) 1810 LHS = Visit(E->getLHS()); 1811 else // Perform promotions, to handle cases like "short ?: int" 1812 LHS = EmitScalarConversion(CondVal, E->getCond()->getType(), E->getType()); 1813 1814 CGF.EndConditionalBranch(); 1815 LHSBlock = Builder.GetInsertBlock(); 1816 CGF.EmitBranch(ContBlock); 1817 1818 CGF.BeginConditionalBranch(); 1819 CGF.EmitBlock(RHSBlock); 1820 1821 Value *RHS = Visit(E->getRHS()); 1822 CGF.EndConditionalBranch(); 1823 RHSBlock = Builder.GetInsertBlock(); 1824 CGF.EmitBranch(ContBlock); 1825 1826 CGF.EmitBlock(ContBlock); 1827 1828 // If the LHS or RHS is a throw expression, it will be legitimately null. 1829 if (!LHS) 1830 return RHS; 1831 if (!RHS) 1832 return LHS; 1833 1834 // Create a PHI node for the real part. 1835 llvm::PHINode *PN = Builder.CreatePHI(LHS->getType(), "cond"); 1836 PN->reserveOperandSpace(2); 1837 PN->addIncoming(LHS, LHSBlock); 1838 PN->addIncoming(RHS, RHSBlock); 1839 return PN; 1840} 1841 1842Value *ScalarExprEmitter::VisitChooseExpr(ChooseExpr *E) { 1843 return Visit(E->getChosenSubExpr(CGF.getContext())); 1844} 1845 1846Value *ScalarExprEmitter::VisitVAArgExpr(VAArgExpr *VE) { 1847 llvm::Value *ArgValue = CGF.EmitVAListRef(VE->getSubExpr()); 1848 llvm::Value *ArgPtr = CGF.EmitVAArg(ArgValue, VE->getType()); 1849 1850 // If EmitVAArg fails, we fall back to the LLVM instruction. 1851 if (!ArgPtr) 1852 return Builder.CreateVAArg(ArgValue, ConvertType(VE->getType())); 1853 1854 // FIXME Volatility. 1855 return Builder.CreateLoad(ArgPtr); 1856} 1857 1858Value *ScalarExprEmitter::VisitBlockExpr(const BlockExpr *BE) { 1859 return CGF.BuildBlockLiteralTmp(BE); 1860} 1861 1862//===----------------------------------------------------------------------===// 1863// Entry Point into this File 1864//===----------------------------------------------------------------------===// 1865 1866/// EmitScalarExpr - Emit the computation of the specified expression of scalar 1867/// type, ignoring the result. 1868Value *CodeGenFunction::EmitScalarExpr(const Expr *E, bool IgnoreResultAssign) { 1869 assert(E && !hasAggregateLLVMType(E->getType()) && 1870 "Invalid scalar expression to emit"); 1871 1872 return ScalarExprEmitter(*this, IgnoreResultAssign) 1873 .Visit(const_cast<Expr*>(E)); 1874} 1875 1876/// EmitScalarConversion - Emit a conversion from the specified type to the 1877/// specified destination type, both of which are LLVM scalar types. 1878Value *CodeGenFunction::EmitScalarConversion(Value *Src, QualType SrcTy, 1879 QualType DstTy) { 1880 assert(!hasAggregateLLVMType(SrcTy) && !hasAggregateLLVMType(DstTy) && 1881 "Invalid scalar expression to emit"); 1882 return ScalarExprEmitter(*this).EmitScalarConversion(Src, SrcTy, DstTy); 1883} 1884 1885/// EmitComplexToScalarConversion - Emit a conversion from the specified complex 1886/// type to the specified destination type, where the destination type is an 1887/// LLVM scalar type. 1888Value *CodeGenFunction::EmitComplexToScalarConversion(ComplexPairTy Src, 1889 QualType SrcTy, 1890 QualType DstTy) { 1891 assert(SrcTy->isAnyComplexType() && !hasAggregateLLVMType(DstTy) && 1892 "Invalid complex -> scalar conversion"); 1893 return ScalarExprEmitter(*this).EmitComplexToScalarConversion(Src, SrcTy, 1894 DstTy); 1895} 1896 1897LValue CodeGenFunction::EmitObjCIsaExpr(const ObjCIsaExpr *E) { 1898 llvm::Value *V; 1899 // object->isa or (*object).isa 1900 // Generate code as for: *(Class*)object 1901 // build Class* type 1902 const llvm::Type *ClassPtrTy = ConvertType(E->getType()); 1903 1904 Expr *BaseExpr = E->getBase(); 1905 if (BaseExpr->isLvalue(getContext()) != Expr::LV_Valid) { 1906 V = CreateTempAlloca(ClassPtrTy, "resval"); 1907 llvm::Value *Src = EmitScalarExpr(BaseExpr); 1908 Builder.CreateStore(Src, V); 1909 LValue LV = LValue::MakeAddr(V, MakeQualifiers(E->getType())); 1910 V = ScalarExprEmitter(*this).EmitLoadOfLValue(LV, E->getType()); 1911 } 1912 else { 1913 if (E->isArrow()) 1914 V = ScalarExprEmitter(*this).EmitLoadOfLValue(BaseExpr); 1915 else 1916 V = EmitLValue(BaseExpr).getAddress(); 1917 } 1918 1919 // build Class* type 1920 ClassPtrTy = ClassPtrTy->getPointerTo(); 1921 V = Builder.CreateBitCast(V, ClassPtrTy); 1922 LValue LV = LValue::MakeAddr(V, MakeQualifiers(E->getType())); 1923 return LV; 1924} 1925 1926 1927LValue CodeGenFunction::EmitCompoundAssignOperatorLValue( 1928 const CompoundAssignOperator *E) { 1929 ScalarExprEmitter Scalar(*this); 1930 Value *BitFieldResult = 0; 1931 switch (E->getOpcode()) { 1932#define COMPOUND_OP(Op) \ 1933 case BinaryOperator::Op##Assign: \ 1934 return Scalar.EmitCompoundAssignLValue(E, &ScalarExprEmitter::Emit##Op, \ 1935 BitFieldResult) 1936 COMPOUND_OP(Mul); 1937 COMPOUND_OP(Div); 1938 COMPOUND_OP(Rem); 1939 COMPOUND_OP(Add); 1940 COMPOUND_OP(Sub); 1941 COMPOUND_OP(Shl); 1942 COMPOUND_OP(Shr); 1943 COMPOUND_OP(And); 1944 COMPOUND_OP(Xor); 1945 COMPOUND_OP(Or); 1946#undef COMPOUND_OP 1947 1948 case BinaryOperator::PtrMemD: 1949 case BinaryOperator::PtrMemI: 1950 case BinaryOperator::Mul: 1951 case BinaryOperator::Div: 1952 case BinaryOperator::Rem: 1953 case BinaryOperator::Add: 1954 case BinaryOperator::Sub: 1955 case BinaryOperator::Shl: 1956 case BinaryOperator::Shr: 1957 case BinaryOperator::LT: 1958 case BinaryOperator::GT: 1959 case BinaryOperator::LE: 1960 case BinaryOperator::GE: 1961 case BinaryOperator::EQ: 1962 case BinaryOperator::NE: 1963 case BinaryOperator::And: 1964 case BinaryOperator::Xor: 1965 case BinaryOperator::Or: 1966 case BinaryOperator::LAnd: 1967 case BinaryOperator::LOr: 1968 case BinaryOperator::Assign: 1969 case BinaryOperator::Comma: 1970 assert(false && "Not valid compound assignment operators"); 1971 break; 1972 } 1973 1974 llvm_unreachable("Unhandled compound assignment operator"); 1975} 1976