Anders Carlsson | 3b1d57b | 2008-01-26 01:36:00 +0000 | [diff] [blame] | 1 | //===--- CGExprConstant.cpp - Emit LLVM Code from Constant Expressions ----===// |
| 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 Constant Expr nodes as LLVM code. |
| 11 | // |
| 12 | //===----------------------------------------------------------------------===// |
| 13 | |
| 14 | #include "CodeGenFunction.h" |
| 15 | #include "CodeGenModule.h" |
| 16 | #include "clang/AST/AST.h" |
| 17 | #include "llvm/Constants.h" |
| 18 | #include "llvm/Function.h" |
| 19 | #include "llvm/GlobalVariable.h" |
| 20 | #include "llvm/Support/Compiler.h" |
| 21 | using namespace clang; |
| 22 | using namespace CodeGen; |
| 23 | |
| 24 | namespace { |
Anders Carlsson | 84005b4 | 2008-01-26 04:30:23 +0000 | [diff] [blame] | 25 | class VISIBILITY_HIDDEN ConstExprEmitter : |
| 26 | public StmtVisitor<ConstExprEmitter, llvm::Constant*> { |
Anders Carlsson | 3b1d57b | 2008-01-26 01:36:00 +0000 | [diff] [blame] | 27 | CodeGenModule &CGM; |
| 28 | public: |
| 29 | ConstExprEmitter(CodeGenModule &cgm) |
| 30 | : CGM(cgm) { |
| 31 | } |
| 32 | |
| 33 | //===--------------------------------------------------------------------===// |
| 34 | // Visitor Methods |
| 35 | //===--------------------------------------------------------------------===// |
| 36 | |
| 37 | llvm::Constant *VisitStmt(Stmt *S) { |
| 38 | CGM.WarnUnsupported(S, "constant expression"); |
Eli Friedman | 546d94c | 2008-02-11 00:23:10 +0000 | [diff] [blame] | 39 | return llvm::UndefValue::get(CGM.getTypes().ConvertType(cast<Expr>(S)->getType())); |
Anders Carlsson | 3b1d57b | 2008-01-26 01:36:00 +0000 | [diff] [blame] | 40 | } |
| 41 | |
| 42 | llvm::Constant *VisitParenExpr(ParenExpr *PE) { |
| 43 | return Visit(PE->getSubExpr()); |
| 44 | } |
| 45 | |
| 46 | // Leaves |
| 47 | llvm::Constant *VisitIntegerLiteral(const IntegerLiteral *E) { |
| 48 | return llvm::ConstantInt::get(E->getValue()); |
| 49 | } |
| 50 | llvm::Constant *VisitFloatingLiteral(const FloatingLiteral *E) { |
| 51 | return llvm::ConstantFP::get(ConvertType(E->getType()), E->getValue()); |
| 52 | } |
| 53 | llvm::Constant *VisitCharacterLiteral(const CharacterLiteral *E) { |
| 54 | return llvm::ConstantInt::get(ConvertType(E->getType()), E->getValue()); |
| 55 | } |
| 56 | llvm::Constant *VisitCXXBoolLiteralExpr(const CXXBoolLiteralExpr *E) { |
| 57 | return llvm::ConstantInt::get(ConvertType(E->getType()), E->getValue()); |
| 58 | } |
| 59 | |
| 60 | llvm::Constant *VisitCompoundLiteralExpr(CompoundLiteralExpr *E) { |
| 61 | return Visit(E->getInitializer()); |
| 62 | } |
| 63 | |
| 64 | llvm::Constant *VisitCastExpr(const CastExpr* E) { |
| 65 | llvm::Constant *C = Visit(E->getSubExpr()); |
| 66 | |
| 67 | return EmitConversion(C, E->getSubExpr()->getType(), E->getType()); |
| 68 | } |
Devang Patel | eae1560 | 2008-02-05 02:39:50 +0000 | [diff] [blame] | 69 | |
| 70 | llvm::Constant *EmitArrayInitialization(InitListExpr *ILE, |
| 71 | const llvm::ArrayType *AType) { |
Eli Friedman | 4d1c018 | 2008-02-21 17:45:41 +0000 | [diff] [blame] | 72 | std::vector<llvm::Constant*> Elts; |
| 73 | unsigned NumInitElements = ILE->getNumInits(); |
| 74 | // FIXME: Check for wide strings |
| 75 | if (NumInitElements > 0 && isa<StringLiteral>(ILE->getInit(0)) && |
| 76 | ILE->getType()->getAsArrayType()->getElementType()->isCharType()) |
| 77 | return Visit(ILE->getInit(0)); |
Devang Patel | eae1560 | 2008-02-05 02:39:50 +0000 | [diff] [blame] | 78 | const llvm::Type *ElemTy = AType->getElementType(); |
| 79 | unsigned NumElements = AType->getNumElements(); |
| 80 | |
| 81 | // Initialising an array requires us to automatically |
| 82 | // initialise any elements that have not been initialised explicitly |
| 83 | unsigned NumInitableElts = std::min(NumInitElements, NumElements); |
| 84 | |
| 85 | // Copy initializer elements. |
| 86 | unsigned i = 0; |
| 87 | for (; i < NumInitableElts; ++i) { |
| 88 | |
| 89 | llvm::Constant *C = Visit(ILE->getInit(i)); |
| 90 | // FIXME: Remove this when sema of initializers is finished (and the code |
| 91 | // above). |
| 92 | if (C == 0 && ILE->getInit(i)->getType()->isVoidType()) { |
| 93 | if (ILE->getType()->isVoidType()) return 0; |
| 94 | return llvm::UndefValue::get(AType); |
| 95 | } |
| 96 | assert (C && "Failed to create initializer expression"); |
| 97 | Elts.push_back(C); |
| 98 | } |
| 99 | |
| 100 | // Initialize remaining array elements. |
| 101 | for (; i < NumElements; ++i) |
| 102 | Elts.push_back(llvm::Constant::getNullValue(ElemTy)); |
| 103 | |
| 104 | return llvm::ConstantArray::get(AType, Elts); |
| 105 | } |
| 106 | |
| 107 | llvm::Constant *EmitStructInitialization(InitListExpr *ILE, |
| 108 | const llvm::StructType *SType) { |
| 109 | |
Chris Lattner | af31913 | 2008-02-05 06:55:31 +0000 | [diff] [blame] | 110 | TagDecl *TD = ILE->getType()->getAsRecordType()->getDecl(); |
Devang Patel | eae1560 | 2008-02-05 02:39:50 +0000 | [diff] [blame] | 111 | std::vector<llvm::Constant*> Elts; |
Chris Lattner | af31913 | 2008-02-05 06:55:31 +0000 | [diff] [blame] | 112 | const CGRecordLayout *CGR = CGM.getTypes().getCGRecordLayout(TD); |
Devang Patel | eae1560 | 2008-02-05 02:39:50 +0000 | [diff] [blame] | 113 | unsigned NumInitElements = ILE->getNumInits(); |
| 114 | unsigned NumElements = SType->getNumElements(); |
Anders Carlsson | 7be3d01 | 2008-02-05 20:54:21 +0000 | [diff] [blame] | 115 | |
Devang Patel | eae1560 | 2008-02-05 02:39:50 +0000 | [diff] [blame] | 116 | // Initialising an structure requires us to automatically |
| 117 | // initialise any elements that have not been initialised explicitly |
| 118 | unsigned NumInitableElts = std::min(NumInitElements, NumElements); |
| 119 | |
| 120 | // Copy initializer elements. Skip padding fields. |
| 121 | unsigned EltNo = 0; // Element no in ILE |
| 122 | unsigned FieldNo = 0; // Field no in SType |
| 123 | while (EltNo < NumInitableElts) { |
| 124 | |
| 125 | // Zero initialize padding field. |
| 126 | if (CGR->isPaddingField(FieldNo)) { |
| 127 | const llvm::Type *FieldTy = SType->getElementType(FieldNo); |
| 128 | Elts.push_back(llvm::Constant::getNullValue(FieldTy)); |
| 129 | FieldNo++; |
| 130 | continue; |
| 131 | } |
| 132 | |
| 133 | llvm::Constant *C = Visit(ILE->getInit(EltNo)); |
| 134 | // FIXME: Remove this when sema of initializers is finished (and the code |
| 135 | // above). |
| 136 | if (C == 0 && ILE->getInit(EltNo)->getType()->isVoidType()) { |
| 137 | if (ILE->getType()->isVoidType()) return 0; |
| 138 | return llvm::UndefValue::get(SType); |
| 139 | } |
| 140 | assert (C && "Failed to create initializer expression"); |
| 141 | Elts.push_back(C); |
| 142 | EltNo++; |
| 143 | FieldNo++; |
| 144 | } |
| 145 | |
| 146 | // Initialize remaining structure elements. |
| 147 | for (unsigned i = Elts.size(); i < NumElements; ++i) { |
| 148 | const llvm::Type *FieldTy = SType->getElementType(i); |
| 149 | Elts.push_back(llvm::Constant::getNullValue(FieldTy)); |
| 150 | } |
| 151 | |
| 152 | return llvm::ConstantStruct::get(SType, Elts); |
| 153 | } |
| 154 | |
| 155 | llvm::Constant *EmitVectorInitialization(InitListExpr *ILE, |
| 156 | const llvm::VectorType *VType) { |
| 157 | |
| 158 | std::vector<llvm::Constant*> Elts; |
| 159 | unsigned NumInitElements = ILE->getNumInits(); |
| 160 | unsigned NumElements = VType->getNumElements(); |
| 161 | |
| 162 | assert (NumInitElements == NumElements |
| 163 | && "Unsufficient vector init elelments"); |
| 164 | // Copy initializer elements. |
| 165 | unsigned i = 0; |
| 166 | for (; i < NumElements; ++i) { |
| 167 | |
| 168 | llvm::Constant *C = Visit(ILE->getInit(i)); |
| 169 | // FIXME: Remove this when sema of initializers is finished (and the code |
| 170 | // above). |
| 171 | if (C == 0 && ILE->getInit(i)->getType()->isVoidType()) { |
| 172 | if (ILE->getType()->isVoidType()) return 0; |
| 173 | return llvm::UndefValue::get(VType); |
| 174 | } |
| 175 | assert (C && "Failed to create initializer expression"); |
| 176 | Elts.push_back(C); |
| 177 | } |
| 178 | |
| 179 | return llvm::ConstantVector::get(VType, Elts); |
| 180 | } |
| 181 | |
Anders Carlsson | 3b1d57b | 2008-01-26 01:36:00 +0000 | [diff] [blame] | 182 | llvm::Constant *VisitInitListExpr(InitListExpr *ILE) { |
Anders Carlsson | f6884ac | 2008-01-29 01:15:48 +0000 | [diff] [blame] | 183 | const llvm::CompositeType *CType = |
| 184 | dyn_cast<llvm::CompositeType>(ConvertType(ILE->getType())); |
| 185 | |
| 186 | if (!CType) { |
| 187 | // We have a scalar in braces. Just use the first element. |
| 188 | return Visit(ILE->getInit(0)); |
Anders Carlsson | 3b1d57b | 2008-01-26 01:36:00 +0000 | [diff] [blame] | 189 | } |
Anders Carlsson | f6884ac | 2008-01-29 01:15:48 +0000 | [diff] [blame] | 190 | |
Devang Patel | eae1560 | 2008-02-05 02:39:50 +0000 | [diff] [blame] | 191 | if (const llvm::ArrayType *AType = dyn_cast<llvm::ArrayType>(CType)) |
| 192 | return EmitArrayInitialization(ILE, AType); |
Devang Patel | 47fb697 | 2008-01-29 23:23:18 +0000 | [diff] [blame] | 193 | |
Devang Patel | eae1560 | 2008-02-05 02:39:50 +0000 | [diff] [blame] | 194 | if (const llvm::StructType *SType = dyn_cast<llvm::StructType>(CType)) |
| 195 | return EmitStructInitialization(ILE, SType); |
Devang Patel | 47fb697 | 2008-01-29 23:23:18 +0000 | [diff] [blame] | 196 | |
Devang Patel | eae1560 | 2008-02-05 02:39:50 +0000 | [diff] [blame] | 197 | if (const llvm::VectorType *VType = dyn_cast<llvm::VectorType>(CType)) |
| 198 | return EmitVectorInitialization(ILE, VType); |
Anders Carlsson | 3b1d57b | 2008-01-26 01:36:00 +0000 | [diff] [blame] | 199 | |
| 200 | // Make sure we have an array at this point |
Devang Patel | eae1560 | 2008-02-05 02:39:50 +0000 | [diff] [blame] | 201 | assert(0 && "Unable to handle InitListExpr"); |
Anders Carlsson | 3b1d57b | 2008-01-26 01:36:00 +0000 | [diff] [blame] | 202 | } |
Eli Friedman | 3b707e7 | 2008-02-21 17:57:49 +0000 | [diff] [blame^] | 203 | |
Anders Carlsson | 3b1d57b | 2008-01-26 01:36:00 +0000 | [diff] [blame] | 204 | llvm::Constant *VisitImplicitCastExpr(ImplicitCastExpr *ICExpr) { |
Eli Friedman | 3b707e7 | 2008-02-21 17:57:49 +0000 | [diff] [blame^] | 205 | Expr* SExpr = ICExpr->getSubExpr(); |
| 206 | QualType SType = SExpr->getType(); |
| 207 | llvm::Constant *C; // the intermediate expression |
| 208 | QualType T; // the type of the intermediate expression |
| 209 | if (SType->isArrayType()) { |
| 210 | // Arrays decay to a pointer to the first element |
| 211 | // VLAs would require special handling, but they can't occur here |
| 212 | C = EmitLValue(SExpr); |
Anders Carlsson | 3b1d57b | 2008-01-26 01:36:00 +0000 | [diff] [blame] | 213 | llvm::Constant *Idx0 = llvm::ConstantInt::get(llvm::Type::Int32Ty, 0); |
Anders Carlsson | 3b1d57b | 2008-01-26 01:36:00 +0000 | [diff] [blame] | 214 | llvm::Constant *Ops[] = {Idx0, Idx0}; |
| 215 | C = llvm::ConstantExpr::getGetElementPtr(C, Ops, 2); |
Eli Friedman | 3b707e7 | 2008-02-21 17:57:49 +0000 | [diff] [blame^] | 216 | |
| 217 | QualType ElemType = SType->getAsArrayType()->getElementType(); |
| 218 | T = CGM.getContext().getPointerType(ElemType); |
| 219 | } else if (SType->isFunctionType()) { |
| 220 | // Function types decay to a pointer to the function |
| 221 | C = EmitLValue(SExpr); |
| 222 | T = CGM.getContext().getPointerType(SType); |
| 223 | } else { |
| 224 | C = Visit(SExpr); |
| 225 | T = SType; |
Anders Carlsson | 3b1d57b | 2008-01-26 01:36:00 +0000 | [diff] [blame] | 226 | } |
Eli Friedman | 3b707e7 | 2008-02-21 17:57:49 +0000 | [diff] [blame^] | 227 | |
| 228 | // Perform the conversion; note that an implicit cast can both promote |
| 229 | // and convert an array/function |
| 230 | return EmitConversion(C, T, ICExpr->getType()); |
Anders Carlsson | 3b1d57b | 2008-01-26 01:36:00 +0000 | [diff] [blame] | 231 | } |
Eli Friedman | 3b707e7 | 2008-02-21 17:57:49 +0000 | [diff] [blame^] | 232 | |
Anders Carlsson | 3b1d57b | 2008-01-26 01:36:00 +0000 | [diff] [blame] | 233 | llvm::Constant *VisitStringLiteral(StringLiteral *E) { |
| 234 | const char *StrData = E->getStrData(); |
| 235 | unsigned Len = E->getByteLength(); |
Chris Lattner | a7ad98f | 2008-02-11 00:02:17 +0000 | [diff] [blame] | 236 | assert(!E->getType()->isPointerType() && "Strings are always arrays"); |
Anders Carlsson | 3b1d57b | 2008-01-26 01:36:00 +0000 | [diff] [blame] | 237 | |
| 238 | // Otherwise this must be a string initializing an array in a static |
| 239 | // initializer. Don't emit it as the address of the string, emit the string |
| 240 | // data itself as an inline array. |
| 241 | const ConstantArrayType *CAT = E->getType()->getAsConstantArrayType(); |
| 242 | assert(CAT && "String isn't pointer or array!"); |
| 243 | |
| 244 | std::string Str(StrData, StrData + Len); |
| 245 | // Null terminate the string before potentially truncating it. |
| 246 | // FIXME: What about wchar_t strings? |
| 247 | Str.push_back(0); |
| 248 | |
| 249 | uint64_t RealLen = CAT->getSize().getZExtValue(); |
| 250 | // String or grow the initializer to the required size. |
| 251 | if (RealLen != Str.size()) |
| 252 | Str.resize(RealLen); |
| 253 | |
| 254 | return llvm::ConstantArray::get(Str, false); |
| 255 | } |
| 256 | |
| 257 | llvm::Constant *VisitDeclRefExpr(DeclRefExpr *E) { |
| 258 | const ValueDecl *Decl = E->getDecl(); |
Anders Carlsson | a3881fc | 2008-01-29 01:28:48 +0000 | [diff] [blame] | 259 | if (const EnumConstantDecl *EC = dyn_cast<EnumConstantDecl>(Decl)) |
| 260 | return llvm::ConstantInt::get(EC->getInitVal()); |
Anders Carlsson | 3b1d57b | 2008-01-26 01:36:00 +0000 | [diff] [blame] | 261 | assert(0 && "Unsupported decl ref type!"); |
| 262 | return 0; |
| 263 | } |
| 264 | |
| 265 | llvm::Constant *VisitSizeOfAlignOfTypeExpr(const SizeOfAlignOfTypeExpr *E) { |
| 266 | return EmitSizeAlignOf(E->getArgumentType(), E->getType(), E->isSizeOf()); |
| 267 | } |
| 268 | |
| 269 | // Unary operators |
| 270 | llvm::Constant *VisitUnaryPlus(const UnaryOperator *E) { |
| 271 | return Visit(E->getSubExpr()); |
| 272 | } |
| 273 | llvm::Constant *VisitUnaryMinus(const UnaryOperator *E) { |
| 274 | return llvm::ConstantExpr::getNeg(Visit(E->getSubExpr())); |
| 275 | } |
| 276 | llvm::Constant *VisitUnaryNot(const UnaryOperator *E) { |
| 277 | return llvm::ConstantExpr::getNot(Visit(E->getSubExpr())); |
| 278 | } |
| 279 | llvm::Constant *VisitUnaryLNot(const UnaryOperator *E) { |
| 280 | llvm::Constant *SubExpr = Visit(E->getSubExpr()); |
| 281 | |
| 282 | if (E->getSubExpr()->getType()->isRealFloatingType()) { |
| 283 | // Compare against 0.0 for fp scalars. |
| 284 | llvm::Constant *Zero = llvm::Constant::getNullValue(SubExpr->getType()); |
| 285 | SubExpr = llvm::ConstantExpr::getFCmp(llvm::FCmpInst::FCMP_UEQ, SubExpr, |
| 286 | Zero); |
| 287 | } else { |
| 288 | assert((E->getSubExpr()->getType()->isIntegerType() || |
| 289 | E->getSubExpr()->getType()->isPointerType()) && |
| 290 | "Unknown scalar type to convert"); |
| 291 | // Compare against an integer or pointer null. |
| 292 | llvm::Constant *Zero = llvm::Constant::getNullValue(SubExpr->getType()); |
| 293 | SubExpr = llvm::ConstantExpr::getICmp(llvm::ICmpInst::ICMP_EQ, SubExpr, |
| 294 | Zero); |
| 295 | } |
| 296 | |
| 297 | return llvm::ConstantExpr::getZExt(SubExpr, ConvertType(E->getType())); |
| 298 | } |
| 299 | llvm::Constant *VisitUnarySizeOf(const UnaryOperator *E) { |
| 300 | return EmitSizeAlignOf(E->getSubExpr()->getType(), E->getType(), true); |
| 301 | } |
| 302 | llvm::Constant *VisitUnaryAlignOf(const UnaryOperator *E) { |
| 303 | return EmitSizeAlignOf(E->getSubExpr()->getType(), E->getType(), false); |
| 304 | } |
Anders Carlsson | e3d3b7d | 2008-01-26 02:08:50 +0000 | [diff] [blame] | 305 | llvm::Constant *VisitUnaryAddrOf(const UnaryOperator *E) { |
| 306 | return EmitLValue(E->getSubExpr()); |
| 307 | } |
Anders Carlsson | 5a1deb8 | 2008-01-29 15:56:48 +0000 | [diff] [blame] | 308 | llvm::Constant *VisitUnaryOffsetOf(const UnaryOperator *E) { |
| 309 | int64_t Val = E->evaluateOffsetOf(CGM.getContext()); |
| 310 | |
| 311 | assert(E->getType()->isIntegerType() && "Result type must be an integer!"); |
| 312 | |
| 313 | uint32_t ResultWidth = static_cast<uint32_t>( |
| 314 | CGM.getContext().getTypeSize(E->getType(), SourceLocation())); |
| 315 | return llvm::ConstantInt::get(llvm::APInt(ResultWidth, Val)); |
| 316 | } |
Anders Carlsson | 3b1d57b | 2008-01-26 01:36:00 +0000 | [diff] [blame] | 317 | |
Anders Carlsson | ce6237e | 2008-01-29 01:33:32 +0000 | [diff] [blame] | 318 | // Binary operators |
| 319 | llvm::Constant *VisitBinOr(const BinaryOperator *E) { |
| 320 | llvm::Constant *LHS = Visit(E->getLHS()); |
| 321 | llvm::Constant *RHS = Visit(E->getRHS()); |
| 322 | |
| 323 | return llvm::ConstantExpr::getOr(LHS, RHS); |
| 324 | } |
Anders Carlsson | 7be3d01 | 2008-02-05 20:54:21 +0000 | [diff] [blame] | 325 | llvm::Constant *VisitBinSub(const BinaryOperator *E) { |
| 326 | llvm::Constant *LHS = Visit(E->getLHS()); |
| 327 | llvm::Constant *RHS = Visit(E->getRHS()); |
| 328 | |
| 329 | if (!isa<llvm::PointerType>(RHS->getType())) { |
| 330 | // pointer - int |
| 331 | if (isa<llvm::PointerType>(LHS->getType())) { |
| 332 | llvm::Constant *Idx = llvm::ConstantExpr::getNeg(RHS); |
| 333 | |
| 334 | return llvm::ConstantExpr::getGetElementPtr(LHS, &Idx, 1); |
| 335 | } |
| 336 | |
| 337 | // int - int |
| 338 | return llvm::ConstantExpr::getSub(LHS, RHS); |
| 339 | } |
| 340 | |
| 341 | assert(0 && "Unhandled bin sub case!"); |
| 342 | return 0; |
| 343 | } |
| 344 | |
| 345 | llvm::Constant *VisitBinShl(const BinaryOperator *E) { |
| 346 | llvm::Constant *LHS = Visit(E->getLHS()); |
| 347 | llvm::Constant *RHS = Visit(E->getRHS()); |
Anders Carlsson | ce6237e | 2008-01-29 01:33:32 +0000 | [diff] [blame] | 348 | |
Anders Carlsson | 7be3d01 | 2008-02-05 20:54:21 +0000 | [diff] [blame] | 349 | // LLVM requires the LHS and RHS to be the same type: promote or truncate the |
| 350 | // RHS to the same size as the LHS. |
| 351 | if (LHS->getType() != RHS->getType()) |
| 352 | RHS = llvm::ConstantExpr::getIntegerCast(RHS, LHS->getType(), false); |
| 353 | |
| 354 | return llvm::ConstantExpr::getShl(LHS, RHS); |
| 355 | } |
| 356 | |
| 357 | llvm::Constant *VisitBinMul(const BinaryOperator *E) { |
| 358 | llvm::Constant *LHS = Visit(E->getLHS()); |
| 359 | llvm::Constant *RHS = Visit(E->getRHS()); |
| 360 | |
| 361 | return llvm::ConstantExpr::getMul(LHS, RHS); |
| 362 | } |
| 363 | |
| 364 | llvm::Constant *VisitBinDiv(const BinaryOperator *E) { |
| 365 | llvm::Constant *LHS = Visit(E->getLHS()); |
| 366 | llvm::Constant *RHS = Visit(E->getRHS()); |
| 367 | |
| 368 | if (LHS->getType()->isFPOrFPVector()) |
| 369 | return llvm::ConstantExpr::getFDiv(LHS, RHS); |
| 370 | else if (E->getType()->isUnsignedIntegerType()) |
| 371 | return llvm::ConstantExpr::getUDiv(LHS, RHS); |
| 372 | else |
| 373 | return llvm::ConstantExpr::getSDiv(LHS, RHS); |
| 374 | } |
| 375 | |
| 376 | llvm::Constant *VisitBinAdd(const BinaryOperator *E) { |
| 377 | llvm::Constant *LHS = Visit(E->getLHS()); |
| 378 | llvm::Constant *RHS = Visit(E->getRHS()); |
| 379 | |
| 380 | if (!E->getType()->isPointerType()) |
| 381 | return llvm::ConstantExpr::getAdd(LHS, RHS); |
| 382 | |
Anders Carlsson | 87a9875 | 2008-02-06 07:23:14 +0000 | [diff] [blame] | 383 | llvm::Constant *Ptr, *Idx; |
| 384 | if (isa<llvm::PointerType>(LHS->getType())) { // pointer + int |
| 385 | Ptr = LHS; |
| 386 | Idx = RHS; |
| 387 | } else { // int + pointer |
| 388 | Ptr = RHS; |
| 389 | Idx = LHS; |
| 390 | } |
| 391 | |
| 392 | return llvm::ConstantExpr::getGetElementPtr(Ptr, &Idx, 1); |
Anders Carlsson | 7be3d01 | 2008-02-05 20:54:21 +0000 | [diff] [blame] | 393 | } |
| 394 | |
| 395 | llvm::Constant *VisitBinAnd(const BinaryOperator *E) { |
| 396 | llvm::Constant *LHS = Visit(E->getLHS()); |
| 397 | llvm::Constant *RHS = Visit(E->getRHS()); |
| 398 | |
| 399 | return llvm::ConstantExpr::getAnd(LHS, RHS); |
| 400 | } |
| 401 | |
Anders Carlsson | 3b1d57b | 2008-01-26 01:36:00 +0000 | [diff] [blame] | 402 | // Utility methods |
| 403 | const llvm::Type *ConvertType(QualType T) { |
| 404 | return CGM.getTypes().ConvertType(T); |
| 405 | } |
| 406 | |
| 407 | llvm::Constant *EmitConversionToBool(llvm::Constant *Src, QualType SrcType) { |
| 408 | assert(SrcType->isCanonical() && "EmitConversion strips typedefs"); |
| 409 | |
| 410 | if (SrcType->isRealFloatingType()) { |
| 411 | // Compare against 0.0 for fp scalars. |
| 412 | llvm::Constant *Zero = llvm::Constant::getNullValue(Src->getType()); |
| 413 | return llvm::ConstantExpr::getFCmp(llvm::FCmpInst::FCMP_UNE, Src, Zero); |
| 414 | } |
| 415 | |
| 416 | assert((SrcType->isIntegerType() || SrcType->isPointerType()) && |
| 417 | "Unknown scalar type to convert"); |
| 418 | |
| 419 | // Compare against an integer or pointer null. |
| 420 | llvm::Constant *Zero = llvm::Constant::getNullValue(Src->getType()); |
| 421 | return llvm::ConstantExpr::getICmp(llvm::ICmpInst::ICMP_NE, Src, Zero); |
| 422 | } |
| 423 | |
| 424 | llvm::Constant *EmitConversion(llvm::Constant *Src, QualType SrcType, |
| 425 | QualType DstType) { |
| 426 | SrcType = SrcType.getCanonicalType(); |
| 427 | DstType = DstType.getCanonicalType(); |
| 428 | if (SrcType == DstType) return Src; |
| 429 | |
| 430 | // Handle conversions to bool first, they are special: comparisons against 0. |
| 431 | if (DstType->isBooleanType()) |
| 432 | return EmitConversionToBool(Src, SrcType); |
| 433 | |
| 434 | const llvm::Type *DstTy = ConvertType(DstType); |
| 435 | |
| 436 | // Ignore conversions like int -> uint. |
| 437 | if (Src->getType() == DstTy) |
| 438 | return Src; |
| 439 | |
| 440 | // Handle pointer conversions next: pointers can only be converted to/from |
| 441 | // other pointers and integers. |
| 442 | if (isa<PointerType>(DstType)) { |
| 443 | // The source value may be an integer, or a pointer. |
| 444 | if (isa<llvm::PointerType>(Src->getType())) |
| 445 | return llvm::ConstantExpr::getBitCast(Src, DstTy); |
Anders Carlsson | 84005b4 | 2008-01-26 04:30:23 +0000 | [diff] [blame] | 446 | assert(SrcType->isIntegerType() &&"Not ptr->ptr or int->ptr conversion?"); |
Anders Carlsson | 3b1d57b | 2008-01-26 01:36:00 +0000 | [diff] [blame] | 447 | return llvm::ConstantExpr::getIntToPtr(Src, DstTy); |
| 448 | } |
| 449 | |
| 450 | if (isa<PointerType>(SrcType)) { |
| 451 | // Must be an ptr to int cast. |
| 452 | assert(isa<llvm::IntegerType>(DstTy) && "not ptr->int?"); |
| 453 | return llvm::ConstantExpr::getPtrToInt(Src, DstTy); |
| 454 | } |
| 455 | |
| 456 | // A scalar source can be splatted to a vector of the same element type |
| 457 | if (isa<llvm::VectorType>(DstTy) && !isa<VectorType>(SrcType)) { |
| 458 | const llvm::VectorType *VT = cast<llvm::VectorType>(DstTy); |
| 459 | assert((VT->getElementType() == Src->getType()) && |
| 460 | "Vector element type must match scalar type to splat."); |
| 461 | unsigned NumElements = DstType->getAsVectorType()->getNumElements(); |
| 462 | llvm::SmallVector<llvm::Constant*, 16> Elements; |
| 463 | for (unsigned i = 0; i < NumElements; i++) |
| 464 | Elements.push_back(Src); |
| 465 | |
| 466 | return llvm::ConstantVector::get(&Elements[0], NumElements); |
| 467 | } |
| 468 | |
| 469 | if (isa<llvm::VectorType>(Src->getType()) || |
| 470 | isa<llvm::VectorType>(DstTy)) { |
| 471 | return llvm::ConstantExpr::getBitCast(Src, DstTy); |
| 472 | } |
| 473 | |
| 474 | // Finally, we have the arithmetic types: real int/float. |
| 475 | if (isa<llvm::IntegerType>(Src->getType())) { |
| 476 | bool InputSigned = SrcType->isSignedIntegerType(); |
| 477 | if (isa<llvm::IntegerType>(DstTy)) |
| 478 | return llvm::ConstantExpr::getIntegerCast(Src, DstTy, InputSigned); |
| 479 | else if (InputSigned) |
| 480 | return llvm::ConstantExpr::getSIToFP(Src, DstTy); |
| 481 | else |
| 482 | return llvm::ConstantExpr::getUIToFP(Src, DstTy); |
| 483 | } |
| 484 | |
| 485 | assert(Src->getType()->isFloatingPoint() && "Unknown real conversion"); |
| 486 | if (isa<llvm::IntegerType>(DstTy)) { |
| 487 | if (DstType->isSignedIntegerType()) |
| 488 | return llvm::ConstantExpr::getFPToSI(Src, DstTy); |
| 489 | else |
| 490 | return llvm::ConstantExpr::getFPToUI(Src, DstTy); |
| 491 | } |
| 492 | |
| 493 | assert(DstTy->isFloatingPoint() && "Unknown real conversion"); |
| 494 | if (DstTy->getTypeID() < Src->getType()->getTypeID()) |
| 495 | return llvm::ConstantExpr::getFPTrunc(Src, DstTy); |
| 496 | else |
| 497 | return llvm::ConstantExpr::getFPExtend(Src, DstTy); |
| 498 | } |
| 499 | |
| 500 | llvm::Constant *EmitSizeAlignOf(QualType TypeToSize, |
| 501 | QualType RetType, bool isSizeOf) { |
| 502 | std::pair<uint64_t, unsigned> Info = |
| 503 | CGM.getContext().getTypeInfo(TypeToSize, SourceLocation()); |
| 504 | |
| 505 | uint64_t Val = isSizeOf ? Info.first : Info.second; |
| 506 | Val /= 8; // Return size in bytes, not bits. |
| 507 | |
| 508 | assert(RetType->isIntegerType() && "Result type must be an integer!"); |
| 509 | |
| 510 | uint32_t ResultWidth = static_cast<uint32_t>( |
| 511 | CGM.getContext().getTypeSize(RetType, SourceLocation())); |
| 512 | return llvm::ConstantInt::get(llvm::APInt(ResultWidth, Val)); |
| 513 | } |
Anders Carlsson | 84005b4 | 2008-01-26 04:30:23 +0000 | [diff] [blame] | 514 | |
| 515 | llvm::Constant *EmitLValue(Expr *E) { |
Anders Carlsson | e3d3b7d | 2008-01-26 02:08:50 +0000 | [diff] [blame] | 516 | switch (E->getStmtClass()) { |
Eli Friedman | 546d94c | 2008-02-11 00:23:10 +0000 | [diff] [blame] | 517 | default: break; |
Anders Carlsson | e3d3b7d | 2008-01-26 02:08:50 +0000 | [diff] [blame] | 518 | case Expr::ParenExprClass: |
| 519 | // Elide parenthesis |
| 520 | return EmitLValue(cast<ParenExpr>(E)->getSubExpr()); |
| 521 | case Expr::CompoundLiteralExprClass: { |
| 522 | // Note that due to the nature of compound literals, this is guaranteed |
| 523 | // to be the only use of the variable, so we just generate it here. |
Anders Carlsson | 84005b4 | 2008-01-26 04:30:23 +0000 | [diff] [blame] | 524 | CompoundLiteralExpr *CLE = cast<CompoundLiteralExpr>(E); |
| 525 | llvm::Constant* C = Visit(CLE->getInitializer()); |
Chris Lattner | a7ad98f | 2008-02-11 00:02:17 +0000 | [diff] [blame] | 526 | C = new llvm::GlobalVariable(C->getType(),E->getType().isConstQualified(), |
Anders Carlsson | e3d3b7d | 2008-01-26 02:08:50 +0000 | [diff] [blame] | 527 | llvm::GlobalValue::InternalLinkage, |
| 528 | C, ".compoundliteral", &CGM.getModule()); |
| 529 | return C; |
Anders Carlsson | 84005b4 | 2008-01-26 04:30:23 +0000 | [diff] [blame] | 530 | } |
Anders Carlsson | e3d3b7d | 2008-01-26 02:08:50 +0000 | [diff] [blame] | 531 | case Expr::DeclRefExprClass: { |
Anders Carlsson | 84005b4 | 2008-01-26 04:30:23 +0000 | [diff] [blame] | 532 | ValueDecl *Decl = cast<DeclRefExpr>(E)->getDecl(); |
Anders Carlsson | e3d3b7d | 2008-01-26 02:08:50 +0000 | [diff] [blame] | 533 | if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(Decl)) |
| 534 | return CGM.GetAddrOfFunctionDecl(FD, false); |
Eli Friedman | 546d94c | 2008-02-11 00:23:10 +0000 | [diff] [blame] | 535 | if (const FileVarDecl* VD = dyn_cast<FileVarDecl>(Decl)) |
Chris Lattner | a7ad98f | 2008-02-11 00:02:17 +0000 | [diff] [blame] | 536 | return CGM.GetAddrOfGlobalVar(VD, false); |
Anders Carlsson | e3d3b7d | 2008-01-26 02:08:50 +0000 | [diff] [blame] | 537 | // We can end up here with static block-scope variables (and others?) |
| 538 | // FIXME: How do we implement block-scope variables?! |
Eli Friedman | 546d94c | 2008-02-11 00:23:10 +0000 | [diff] [blame] | 539 | break; |
Anders Carlsson | e3d3b7d | 2008-01-26 02:08:50 +0000 | [diff] [blame] | 540 | } |
| 541 | case Expr::MemberExprClass: { |
Anders Carlsson | 84005b4 | 2008-01-26 04:30:23 +0000 | [diff] [blame] | 542 | MemberExpr* ME = cast<MemberExpr>(E); |
Anders Carlsson | 84005b4 | 2008-01-26 04:30:23 +0000 | [diff] [blame] | 543 | llvm::Constant *Base; |
| 544 | if (ME->isArrow()) |
| 545 | Base = Visit(ME->getBase()); |
| 546 | else |
| 547 | Base = EmitLValue(ME->getBase()); |
Lauro Ramos Venancio | 5bfe18c | 2008-01-30 21:23:20 +0000 | [diff] [blame] | 548 | |
| 549 | unsigned FieldNumber = CGM.getTypes().getLLVMFieldNo(ME->getMemberDecl()); |
Anders Carlsson | e3d3b7d | 2008-01-26 02:08:50 +0000 | [diff] [blame] | 550 | llvm::Constant *Zero = llvm::ConstantInt::get(llvm::Type::Int32Ty, 0); |
| 551 | llvm::Constant *Idx = llvm::ConstantInt::get(llvm::Type::Int32Ty, |
| 552 | FieldNumber); |
| 553 | llvm::Value *Ops[] = {Zero, Idx}; |
| 554 | return llvm::ConstantExpr::getGetElementPtr(Base, Ops, 2); |
| 555 | } |
| 556 | case Expr::ArraySubscriptExprClass: { |
Anders Carlsson | 84005b4 | 2008-01-26 04:30:23 +0000 | [diff] [blame] | 557 | ArraySubscriptExpr* ASExpr = cast<ArraySubscriptExpr>(E); |
| 558 | llvm::Constant *Base = Visit(ASExpr->getBase()); |
| 559 | llvm::Constant *Index = Visit(ASExpr->getIdx()); |
Anders Carlsson | e3d3b7d | 2008-01-26 02:08:50 +0000 | [diff] [blame] | 560 | assert(!ASExpr->getBase()->getType()->isVectorType() && |
| 561 | "Taking the address of a vector component is illegal!"); |
| 562 | return llvm::ConstantExpr::getGetElementPtr(Base, &Index, 1); |
| 563 | } |
| 564 | case Expr::StringLiteralClass: { |
Anders Carlsson | 84005b4 | 2008-01-26 04:30:23 +0000 | [diff] [blame] | 565 | StringLiteral *String = cast<StringLiteral>(E); |
Anders Carlsson | e3d3b7d | 2008-01-26 02:08:50 +0000 | [diff] [blame] | 566 | assert(!String->isWide() && "Cannot codegen wide strings yet"); |
Anders Carlsson | 84005b4 | 2008-01-26 04:30:23 +0000 | [diff] [blame] | 567 | const char *StrData = String->getStrData(); |
| 568 | unsigned Len = String->getByteLength(); |
Anders Carlsson | e3d3b7d | 2008-01-26 02:08:50 +0000 | [diff] [blame] | 569 | |
Anders Carlsson | 84005b4 | 2008-01-26 04:30:23 +0000 | [diff] [blame] | 570 | return CGM.GetAddrOfConstantString(std::string(StrData, StrData + Len)); |
| 571 | } |
| 572 | case Expr::UnaryOperatorClass: { |
| 573 | UnaryOperator *Exp = cast<UnaryOperator>(E); |
| 574 | switch (Exp->getOpcode()) { |
Eli Friedman | 546d94c | 2008-02-11 00:23:10 +0000 | [diff] [blame] | 575 | default: break; |
| 576 | case UnaryOperator::Extension: |
Anders Carlsson | 84005b4 | 2008-01-26 04:30:23 +0000 | [diff] [blame] | 577 | // Extension is just a wrapper for expressions |
| 578 | return EmitLValue(Exp->getSubExpr()); |
| 579 | case UnaryOperator::Real: |
| 580 | case UnaryOperator::Imag: { |
| 581 | // The address of __real or __imag is just a GEP off the address |
| 582 | // of the internal expression |
| 583 | llvm::Constant* C = EmitLValue(Exp->getSubExpr()); |
| 584 | llvm::Constant *Zero = llvm::ConstantInt::get(llvm::Type::Int32Ty, 0); |
| 585 | llvm::Constant *Idx = llvm::ConstantInt::get(llvm::Type::Int32Ty, |
Anders Carlsson | e3d3b7d | 2008-01-26 02:08:50 +0000 | [diff] [blame] | 586 | Exp->getOpcode() == UnaryOperator::Imag); |
Anders Carlsson | 84005b4 | 2008-01-26 04:30:23 +0000 | [diff] [blame] | 587 | llvm::Value *Ops[] = {Zero, Idx}; |
| 588 | return llvm::ConstantExpr::getGetElementPtr(C, Ops, 2); |
| 589 | } |
| 590 | case UnaryOperator::Deref: |
| 591 | // The address of a deref is just the value of the expression |
| 592 | return Visit(Exp->getSubExpr()); |
| 593 | } |
Eli Friedman | 546d94c | 2008-02-11 00:23:10 +0000 | [diff] [blame] | 594 | break; |
Anders Carlsson | e3d3b7d | 2008-01-26 02:08:50 +0000 | [diff] [blame] | 595 | } |
Eli Friedman | 546d94c | 2008-02-11 00:23:10 +0000 | [diff] [blame] | 596 | } |
| 597 | CGM.WarnUnsupported(E, "constant l-value expression"); |
| 598 | llvm::Type *Ty = llvm::PointerType::getUnqual(ConvertType(E->getType())); |
| 599 | return llvm::UndefValue::get(Ty); |
Anders Carlsson | e3d3b7d | 2008-01-26 02:08:50 +0000 | [diff] [blame] | 600 | } |
Anders Carlsson | e3d3b7d | 2008-01-26 02:08:50 +0000 | [diff] [blame] | 601 | |
| 602 | }; |
| 603 | |
Anders Carlsson | 3b1d57b | 2008-01-26 01:36:00 +0000 | [diff] [blame] | 604 | } // end anonymous namespace. |
| 605 | |
| 606 | |
| 607 | llvm::Constant *CodeGenModule::EmitConstantExpr(const Expr *E) |
| 608 | { |
| 609 | QualType type = E->getType().getCanonicalType(); |
| 610 | |
| 611 | if (type->isIntegerType()) { |
| 612 | llvm::APSInt |
| 613 | Value(static_cast<uint32_t>(Context.getTypeSize(type, SourceLocation()))); |
| 614 | if (E->isIntegerConstantExpr(Value, Context)) { |
| 615 | return llvm::ConstantInt::get(Value); |
| 616 | } |
| 617 | } |
| 618 | |
| 619 | return ConstExprEmitter(*this).Visit(const_cast<Expr*>(E)); |
| 620 | } |