| File: | tools/clang/lib/CodeGen/CGExprConstant.cpp |
| Warning: | line 1711, column 19 Value stored to 'C' during its initialization is never read |
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| 1 | //===--- CGExprConstant.cpp - Emit LLVM Code from Constant Expressions ----===// |
| 2 | // |
| 3 | // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
| 4 | // See https://llvm.org/LICENSE.txt for license information. |
| 5 | // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
| 6 | // |
| 7 | //===----------------------------------------------------------------------===// |
| 8 | // |
| 9 | // This contains code to emit Constant Expr nodes as LLVM code. |
| 10 | // |
| 11 | //===----------------------------------------------------------------------===// |
| 12 | |
| 13 | #include "CodeGenFunction.h" |
| 14 | #include "CGCXXABI.h" |
| 15 | #include "CGObjCRuntime.h" |
| 16 | #include "CGRecordLayout.h" |
| 17 | #include "CodeGenModule.h" |
| 18 | #include "ConstantEmitter.h" |
| 19 | #include "TargetInfo.h" |
| 20 | #include "clang/AST/APValue.h" |
| 21 | #include "clang/AST/ASTContext.h" |
| 22 | #include "clang/AST/RecordLayout.h" |
| 23 | #include "clang/AST/StmtVisitor.h" |
| 24 | #include "clang/Basic/Builtins.h" |
| 25 | #include "llvm/IR/Constants.h" |
| 26 | #include "llvm/IR/DataLayout.h" |
| 27 | #include "llvm/IR/Function.h" |
| 28 | #include "llvm/IR/GlobalVariable.h" |
| 29 | using namespace clang; |
| 30 | using namespace CodeGen; |
| 31 | |
| 32 | //===----------------------------------------------------------------------===// |
| 33 | // ConstStructBuilder |
| 34 | //===----------------------------------------------------------------------===// |
| 35 | |
| 36 | namespace { |
| 37 | class ConstExprEmitter; |
| 38 | class ConstStructBuilder { |
| 39 | CodeGenModule &CGM; |
| 40 | ConstantEmitter &Emitter; |
| 41 | |
| 42 | bool Packed; |
| 43 | CharUnits NextFieldOffsetInChars; |
| 44 | CharUnits LLVMStructAlignment; |
| 45 | SmallVector<llvm::Constant *, 32> Elements; |
| 46 | public: |
| 47 | static llvm::Constant *BuildStruct(ConstantEmitter &Emitter, |
| 48 | ConstExprEmitter *ExprEmitter, |
| 49 | llvm::Constant *Base, |
| 50 | InitListExpr *Updater, |
| 51 | QualType ValTy); |
| 52 | static llvm::Constant *BuildStruct(ConstantEmitter &Emitter, |
| 53 | InitListExpr *ILE, QualType StructTy); |
| 54 | static llvm::Constant *BuildStruct(ConstantEmitter &Emitter, |
| 55 | const APValue &Value, QualType ValTy); |
| 56 | |
| 57 | private: |
| 58 | ConstStructBuilder(ConstantEmitter &emitter) |
| 59 | : CGM(emitter.CGM), Emitter(emitter), Packed(false), |
| 60 | NextFieldOffsetInChars(CharUnits::Zero()), |
| 61 | LLVMStructAlignment(CharUnits::One()) { } |
| 62 | |
| 63 | void AppendField(const FieldDecl *Field, uint64_t FieldOffset, |
| 64 | llvm::Constant *InitExpr); |
| 65 | |
| 66 | void AppendBytes(CharUnits FieldOffsetInChars, llvm::Constant *InitCst); |
| 67 | |
| 68 | void AppendBitField(const FieldDecl *Field, uint64_t FieldOffset, |
| 69 | llvm::ConstantInt *InitExpr); |
| 70 | |
| 71 | void AppendPadding(CharUnits PadSize); |
| 72 | |
| 73 | void AppendTailPadding(CharUnits RecordSize); |
| 74 | |
| 75 | void ConvertStructToPacked(); |
| 76 | |
| 77 | bool Build(InitListExpr *ILE); |
| 78 | bool Build(ConstExprEmitter *Emitter, llvm::Constant *Base, |
| 79 | InitListExpr *Updater); |
| 80 | bool Build(const APValue &Val, const RecordDecl *RD, bool IsPrimaryBase, |
| 81 | const CXXRecordDecl *VTableClass, CharUnits BaseOffset); |
| 82 | llvm::Constant *Finalize(QualType Ty); |
| 83 | |
| 84 | CharUnits getAlignment(const llvm::Constant *C) const { |
| 85 | if (Packed) return CharUnits::One(); |
| 86 | return CharUnits::fromQuantity( |
| 87 | CGM.getDataLayout().getABITypeAlignment(C->getType())); |
| 88 | } |
| 89 | |
| 90 | CharUnits getSizeInChars(const llvm::Constant *C) const { |
| 91 | return CharUnits::fromQuantity( |
| 92 | CGM.getDataLayout().getTypeAllocSize(C->getType())); |
| 93 | } |
| 94 | }; |
| 95 | |
| 96 | void ConstStructBuilder:: |
| 97 | AppendField(const FieldDecl *Field, uint64_t FieldOffset, |
| 98 | llvm::Constant *InitCst) { |
| 99 | const ASTContext &Context = CGM.getContext(); |
| 100 | |
| 101 | CharUnits FieldOffsetInChars = Context.toCharUnitsFromBits(FieldOffset); |
| 102 | |
| 103 | AppendBytes(FieldOffsetInChars, InitCst); |
| 104 | } |
| 105 | |
| 106 | void ConstStructBuilder:: |
| 107 | AppendBytes(CharUnits FieldOffsetInChars, llvm::Constant *InitCst) { |
| 108 | |
| 109 | assert(NextFieldOffsetInChars <= FieldOffsetInChars((NextFieldOffsetInChars <= FieldOffsetInChars && "Field offset mismatch!" ) ? static_cast<void> (0) : __assert_fail ("NextFieldOffsetInChars <= FieldOffsetInChars && \"Field offset mismatch!\"" , "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 110, __PRETTY_FUNCTION__)) |
| 110 | && "Field offset mismatch!")((NextFieldOffsetInChars <= FieldOffsetInChars && "Field offset mismatch!" ) ? static_cast<void> (0) : __assert_fail ("NextFieldOffsetInChars <= FieldOffsetInChars && \"Field offset mismatch!\"" , "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 110, __PRETTY_FUNCTION__)); |
| 111 | |
| 112 | CharUnits FieldAlignment = getAlignment(InitCst); |
| 113 | |
| 114 | // Round up the field offset to the alignment of the field type. |
| 115 | CharUnits AlignedNextFieldOffsetInChars = |
| 116 | NextFieldOffsetInChars.alignTo(FieldAlignment); |
| 117 | |
| 118 | if (AlignedNextFieldOffsetInChars < FieldOffsetInChars) { |
| 119 | // We need to append padding. |
| 120 | AppendPadding(FieldOffsetInChars - NextFieldOffsetInChars); |
| 121 | |
| 122 | assert(NextFieldOffsetInChars == FieldOffsetInChars &&((NextFieldOffsetInChars == FieldOffsetInChars && "Did not add enough padding!" ) ? static_cast<void> (0) : __assert_fail ("NextFieldOffsetInChars == FieldOffsetInChars && \"Did not add enough padding!\"" , "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 123, __PRETTY_FUNCTION__)) |
| 123 | "Did not add enough padding!")((NextFieldOffsetInChars == FieldOffsetInChars && "Did not add enough padding!" ) ? static_cast<void> (0) : __assert_fail ("NextFieldOffsetInChars == FieldOffsetInChars && \"Did not add enough padding!\"" , "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 123, __PRETTY_FUNCTION__)); |
| 124 | |
| 125 | AlignedNextFieldOffsetInChars = |
| 126 | NextFieldOffsetInChars.alignTo(FieldAlignment); |
| 127 | } |
| 128 | |
| 129 | if (AlignedNextFieldOffsetInChars > FieldOffsetInChars) { |
| 130 | assert(!Packed && "Alignment is wrong even with a packed struct!")((!Packed && "Alignment is wrong even with a packed struct!" ) ? static_cast<void> (0) : __assert_fail ("!Packed && \"Alignment is wrong even with a packed struct!\"" , "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 130, __PRETTY_FUNCTION__)); |
| 131 | |
| 132 | // Convert the struct to a packed struct. |
| 133 | ConvertStructToPacked(); |
| 134 | |
| 135 | // After we pack the struct, we may need to insert padding. |
| 136 | if (NextFieldOffsetInChars < FieldOffsetInChars) { |
| 137 | // We need to append padding. |
| 138 | AppendPadding(FieldOffsetInChars - NextFieldOffsetInChars); |
| 139 | |
| 140 | assert(NextFieldOffsetInChars == FieldOffsetInChars &&((NextFieldOffsetInChars == FieldOffsetInChars && "Did not add enough padding!" ) ? static_cast<void> (0) : __assert_fail ("NextFieldOffsetInChars == FieldOffsetInChars && \"Did not add enough padding!\"" , "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 141, __PRETTY_FUNCTION__)) |
| 141 | "Did not add enough padding!")((NextFieldOffsetInChars == FieldOffsetInChars && "Did not add enough padding!" ) ? static_cast<void> (0) : __assert_fail ("NextFieldOffsetInChars == FieldOffsetInChars && \"Did not add enough padding!\"" , "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 141, __PRETTY_FUNCTION__)); |
| 142 | } |
| 143 | AlignedNextFieldOffsetInChars = NextFieldOffsetInChars; |
| 144 | } |
| 145 | |
| 146 | // Add the field. |
| 147 | Elements.push_back(InitCst); |
| 148 | NextFieldOffsetInChars = AlignedNextFieldOffsetInChars + |
| 149 | getSizeInChars(InitCst); |
| 150 | |
| 151 | if (Packed) |
| 152 | assert(LLVMStructAlignment == CharUnits::One() &&((LLVMStructAlignment == CharUnits::One() && "Packed struct not byte-aligned!" ) ? static_cast<void> (0) : __assert_fail ("LLVMStructAlignment == CharUnits::One() && \"Packed struct not byte-aligned!\"" , "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 153, __PRETTY_FUNCTION__)) |
| 153 | "Packed struct not byte-aligned!")((LLVMStructAlignment == CharUnits::One() && "Packed struct not byte-aligned!" ) ? static_cast<void> (0) : __assert_fail ("LLVMStructAlignment == CharUnits::One() && \"Packed struct not byte-aligned!\"" , "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 153, __PRETTY_FUNCTION__)); |
| 154 | else |
| 155 | LLVMStructAlignment = std::max(LLVMStructAlignment, FieldAlignment); |
| 156 | } |
| 157 | |
| 158 | void ConstStructBuilder::AppendBitField(const FieldDecl *Field, |
| 159 | uint64_t FieldOffset, |
| 160 | llvm::ConstantInt *CI) { |
| 161 | const ASTContext &Context = CGM.getContext(); |
| 162 | const uint64_t CharWidth = Context.getCharWidth(); |
| 163 | uint64_t NextFieldOffsetInBits = Context.toBits(NextFieldOffsetInChars); |
| 164 | if (FieldOffset > NextFieldOffsetInBits) { |
| 165 | // We need to add padding. |
| 166 | CharUnits PadSize = Context.toCharUnitsFromBits( |
| 167 | llvm::alignTo(FieldOffset - NextFieldOffsetInBits, |
| 168 | Context.getTargetInfo().getCharAlign())); |
| 169 | |
| 170 | AppendPadding(PadSize); |
| 171 | } |
| 172 | |
| 173 | uint64_t FieldSize = Field->getBitWidthValue(Context); |
| 174 | |
| 175 | llvm::APInt FieldValue = CI->getValue(); |
| 176 | |
| 177 | // Promote the size of FieldValue if necessary |
| 178 | // FIXME: This should never occur, but currently it can because initializer |
| 179 | // constants are cast to bool, and because clang is not enforcing bitfield |
| 180 | // width limits. |
| 181 | if (FieldSize > FieldValue.getBitWidth()) |
| 182 | FieldValue = FieldValue.zext(FieldSize); |
| 183 | |
| 184 | // Truncate the size of FieldValue to the bit field size. |
| 185 | if (FieldSize < FieldValue.getBitWidth()) |
| 186 | FieldValue = FieldValue.trunc(FieldSize); |
| 187 | |
| 188 | NextFieldOffsetInBits = Context.toBits(NextFieldOffsetInChars); |
| 189 | if (FieldOffset < NextFieldOffsetInBits) { |
| 190 | // Either part of the field or the entire field can go into the previous |
| 191 | // byte. |
| 192 | assert(!Elements.empty() && "Elements can't be empty!")((!Elements.empty() && "Elements can't be empty!") ? static_cast <void> (0) : __assert_fail ("!Elements.empty() && \"Elements can't be empty!\"" , "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 192, __PRETTY_FUNCTION__)); |
| 193 | |
| 194 | unsigned BitsInPreviousByte = NextFieldOffsetInBits - FieldOffset; |
| 195 | |
| 196 | bool FitsCompletelyInPreviousByte = |
| 197 | BitsInPreviousByte >= FieldValue.getBitWidth(); |
| 198 | |
| 199 | llvm::APInt Tmp = FieldValue; |
| 200 | |
| 201 | if (!FitsCompletelyInPreviousByte) { |
| 202 | unsigned NewFieldWidth = FieldSize - BitsInPreviousByte; |
| 203 | |
| 204 | if (CGM.getDataLayout().isBigEndian()) { |
| 205 | Tmp.lshrInPlace(NewFieldWidth); |
| 206 | Tmp = Tmp.trunc(BitsInPreviousByte); |
| 207 | |
| 208 | // We want the remaining high bits. |
| 209 | FieldValue = FieldValue.trunc(NewFieldWidth); |
| 210 | } else { |
| 211 | Tmp = Tmp.trunc(BitsInPreviousByte); |
| 212 | |
| 213 | // We want the remaining low bits. |
| 214 | FieldValue.lshrInPlace(BitsInPreviousByte); |
| 215 | FieldValue = FieldValue.trunc(NewFieldWidth); |
| 216 | } |
| 217 | } |
| 218 | |
| 219 | Tmp = Tmp.zext(CharWidth); |
| 220 | if (CGM.getDataLayout().isBigEndian()) { |
| 221 | if (FitsCompletelyInPreviousByte) |
| 222 | Tmp = Tmp.shl(BitsInPreviousByte - FieldValue.getBitWidth()); |
| 223 | } else { |
| 224 | Tmp = Tmp.shl(CharWidth - BitsInPreviousByte); |
| 225 | } |
| 226 | |
| 227 | // 'or' in the bits that go into the previous byte. |
| 228 | llvm::Value *LastElt = Elements.back(); |
| 229 | if (llvm::ConstantInt *Val = dyn_cast<llvm::ConstantInt>(LastElt)) |
| 230 | Tmp |= Val->getValue(); |
| 231 | else { |
| 232 | assert(isa<llvm::UndefValue>(LastElt))((isa<llvm::UndefValue>(LastElt)) ? static_cast<void > (0) : __assert_fail ("isa<llvm::UndefValue>(LastElt)" , "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 232, __PRETTY_FUNCTION__)); |
| 233 | // If there is an undef field that we're adding to, it can either be a |
| 234 | // scalar undef (in which case, we just replace it with our field) or it |
| 235 | // is an array. If it is an array, we have to pull one byte off the |
| 236 | // array so that the other undef bytes stay around. |
| 237 | if (!isa<llvm::IntegerType>(LastElt->getType())) { |
| 238 | // The undef padding will be a multibyte array, create a new smaller |
| 239 | // padding and then an hole for our i8 to get plopped into. |
| 240 | assert(isa<llvm::ArrayType>(LastElt->getType()) &&((isa<llvm::ArrayType>(LastElt->getType()) && "Expected array padding of undefs") ? static_cast<void> (0) : __assert_fail ("isa<llvm::ArrayType>(LastElt->getType()) && \"Expected array padding of undefs\"" , "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 241, __PRETTY_FUNCTION__)) |
| 241 | "Expected array padding of undefs")((isa<llvm::ArrayType>(LastElt->getType()) && "Expected array padding of undefs") ? static_cast<void> (0) : __assert_fail ("isa<llvm::ArrayType>(LastElt->getType()) && \"Expected array padding of undefs\"" , "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 241, __PRETTY_FUNCTION__)); |
| 242 | llvm::ArrayType *AT = cast<llvm::ArrayType>(LastElt->getType()); |
| 243 | assert(AT->getElementType()->isIntegerTy(CharWidth) &&((AT->getElementType()->isIntegerTy(CharWidth) && AT->getNumElements() != 0 && "Expected non-empty array padding of undefs" ) ? static_cast<void> (0) : __assert_fail ("AT->getElementType()->isIntegerTy(CharWidth) && AT->getNumElements() != 0 && \"Expected non-empty array padding of undefs\"" , "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 245, __PRETTY_FUNCTION__)) |
| 244 | AT->getNumElements() != 0 &&((AT->getElementType()->isIntegerTy(CharWidth) && AT->getNumElements() != 0 && "Expected non-empty array padding of undefs" ) ? static_cast<void> (0) : __assert_fail ("AT->getElementType()->isIntegerTy(CharWidth) && AT->getNumElements() != 0 && \"Expected non-empty array padding of undefs\"" , "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 245, __PRETTY_FUNCTION__)) |
| 245 | "Expected non-empty array padding of undefs")((AT->getElementType()->isIntegerTy(CharWidth) && AT->getNumElements() != 0 && "Expected non-empty array padding of undefs" ) ? static_cast<void> (0) : __assert_fail ("AT->getElementType()->isIntegerTy(CharWidth) && AT->getNumElements() != 0 && \"Expected non-empty array padding of undefs\"" , "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 245, __PRETTY_FUNCTION__)); |
| 246 | |
| 247 | // Remove the padding array. |
| 248 | NextFieldOffsetInChars -= CharUnits::fromQuantity(AT->getNumElements()); |
| 249 | Elements.pop_back(); |
| 250 | |
| 251 | // Add the padding back in two chunks. |
| 252 | AppendPadding(CharUnits::fromQuantity(AT->getNumElements()-1)); |
| 253 | AppendPadding(CharUnits::One()); |
| 254 | assert(isa<llvm::UndefValue>(Elements.back()) &&((isa<llvm::UndefValue>(Elements.back()) && Elements .back()->getType()->isIntegerTy(CharWidth) && "Padding addition didn't work right" ) ? static_cast<void> (0) : __assert_fail ("isa<llvm::UndefValue>(Elements.back()) && Elements.back()->getType()->isIntegerTy(CharWidth) && \"Padding addition didn't work right\"" , "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 256, __PRETTY_FUNCTION__)) |
| 255 | Elements.back()->getType()->isIntegerTy(CharWidth) &&((isa<llvm::UndefValue>(Elements.back()) && Elements .back()->getType()->isIntegerTy(CharWidth) && "Padding addition didn't work right" ) ? static_cast<void> (0) : __assert_fail ("isa<llvm::UndefValue>(Elements.back()) && Elements.back()->getType()->isIntegerTy(CharWidth) && \"Padding addition didn't work right\"" , "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 256, __PRETTY_FUNCTION__)) |
| 256 | "Padding addition didn't work right")((isa<llvm::UndefValue>(Elements.back()) && Elements .back()->getType()->isIntegerTy(CharWidth) && "Padding addition didn't work right" ) ? static_cast<void> (0) : __assert_fail ("isa<llvm::UndefValue>(Elements.back()) && Elements.back()->getType()->isIntegerTy(CharWidth) && \"Padding addition didn't work right\"" , "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 256, __PRETTY_FUNCTION__)); |
| 257 | } |
| 258 | } |
| 259 | |
| 260 | Elements.back() = llvm::ConstantInt::get(CGM.getLLVMContext(), Tmp); |
| 261 | |
| 262 | if (FitsCompletelyInPreviousByte) |
| 263 | return; |
| 264 | } |
| 265 | |
| 266 | while (FieldValue.getBitWidth() > CharWidth) { |
| 267 | llvm::APInt Tmp; |
| 268 | |
| 269 | if (CGM.getDataLayout().isBigEndian()) { |
| 270 | // We want the high bits. |
| 271 | Tmp = |
| 272 | FieldValue.lshr(FieldValue.getBitWidth() - CharWidth).trunc(CharWidth); |
| 273 | } else { |
| 274 | // We want the low bits. |
| 275 | Tmp = FieldValue.trunc(CharWidth); |
| 276 | |
| 277 | FieldValue.lshrInPlace(CharWidth); |
| 278 | } |
| 279 | |
| 280 | Elements.push_back(llvm::ConstantInt::get(CGM.getLLVMContext(), Tmp)); |
| 281 | ++NextFieldOffsetInChars; |
| 282 | |
| 283 | FieldValue = FieldValue.trunc(FieldValue.getBitWidth() - CharWidth); |
| 284 | } |
| 285 | |
| 286 | assert(FieldValue.getBitWidth() > 0 &&((FieldValue.getBitWidth() > 0 && "Should have at least one bit left!" ) ? static_cast<void> (0) : __assert_fail ("FieldValue.getBitWidth() > 0 && \"Should have at least one bit left!\"" , "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 287, __PRETTY_FUNCTION__)) |
| 287 | "Should have at least one bit left!")((FieldValue.getBitWidth() > 0 && "Should have at least one bit left!" ) ? static_cast<void> (0) : __assert_fail ("FieldValue.getBitWidth() > 0 && \"Should have at least one bit left!\"" , "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 287, __PRETTY_FUNCTION__)); |
| 288 | assert(FieldValue.getBitWidth() <= CharWidth &&((FieldValue.getBitWidth() <= CharWidth && "Should not have more than a byte left!" ) ? static_cast<void> (0) : __assert_fail ("FieldValue.getBitWidth() <= CharWidth && \"Should not have more than a byte left!\"" , "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 289, __PRETTY_FUNCTION__)) |
| 289 | "Should not have more than a byte left!")((FieldValue.getBitWidth() <= CharWidth && "Should not have more than a byte left!" ) ? static_cast<void> (0) : __assert_fail ("FieldValue.getBitWidth() <= CharWidth && \"Should not have more than a byte left!\"" , "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 289, __PRETTY_FUNCTION__)); |
| 290 | |
| 291 | if (FieldValue.getBitWidth() < CharWidth) { |
| 292 | if (CGM.getDataLayout().isBigEndian()) { |
| 293 | unsigned BitWidth = FieldValue.getBitWidth(); |
| 294 | |
| 295 | FieldValue = FieldValue.zext(CharWidth) << (CharWidth - BitWidth); |
| 296 | } else |
| 297 | FieldValue = FieldValue.zext(CharWidth); |
| 298 | } |
| 299 | |
| 300 | // Append the last element. |
| 301 | Elements.push_back(llvm::ConstantInt::get(CGM.getLLVMContext(), |
| 302 | FieldValue)); |
| 303 | ++NextFieldOffsetInChars; |
| 304 | } |
| 305 | |
| 306 | void ConstStructBuilder::AppendPadding(CharUnits PadSize) { |
| 307 | if (PadSize.isZero()) |
| 308 | return; |
| 309 | |
| 310 | llvm::Type *Ty = CGM.Int8Ty; |
| 311 | if (PadSize > CharUnits::One()) |
| 312 | Ty = llvm::ArrayType::get(Ty, PadSize.getQuantity()); |
| 313 | |
| 314 | llvm::Constant *C = llvm::UndefValue::get(Ty); |
| 315 | Elements.push_back(C); |
| 316 | assert(getAlignment(C) == CharUnits::One() &&((getAlignment(C) == CharUnits::One() && "Padding must have 1 byte alignment!" ) ? static_cast<void> (0) : __assert_fail ("getAlignment(C) == CharUnits::One() && \"Padding must have 1 byte alignment!\"" , "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 317, __PRETTY_FUNCTION__)) |
| 317 | "Padding must have 1 byte alignment!")((getAlignment(C) == CharUnits::One() && "Padding must have 1 byte alignment!" ) ? static_cast<void> (0) : __assert_fail ("getAlignment(C) == CharUnits::One() && \"Padding must have 1 byte alignment!\"" , "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 317, __PRETTY_FUNCTION__)); |
| 318 | |
| 319 | NextFieldOffsetInChars += getSizeInChars(C); |
| 320 | } |
| 321 | |
| 322 | void ConstStructBuilder::AppendTailPadding(CharUnits RecordSize) { |
| 323 | assert(NextFieldOffsetInChars <= RecordSize &&((NextFieldOffsetInChars <= RecordSize && "Size mismatch!" ) ? static_cast<void> (0) : __assert_fail ("NextFieldOffsetInChars <= RecordSize && \"Size mismatch!\"" , "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 324, __PRETTY_FUNCTION__)) |
| 324 | "Size mismatch!")((NextFieldOffsetInChars <= RecordSize && "Size mismatch!" ) ? static_cast<void> (0) : __assert_fail ("NextFieldOffsetInChars <= RecordSize && \"Size mismatch!\"" , "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 324, __PRETTY_FUNCTION__)); |
| 325 | |
| 326 | AppendPadding(RecordSize - NextFieldOffsetInChars); |
| 327 | } |
| 328 | |
| 329 | void ConstStructBuilder::ConvertStructToPacked() { |
| 330 | SmallVector<llvm::Constant *, 16> PackedElements; |
| 331 | CharUnits ElementOffsetInChars = CharUnits::Zero(); |
| 332 | |
| 333 | for (unsigned i = 0, e = Elements.size(); i != e; ++i) { |
| 334 | llvm::Constant *C = Elements[i]; |
| 335 | |
| 336 | CharUnits ElementAlign = CharUnits::fromQuantity( |
| 337 | CGM.getDataLayout().getABITypeAlignment(C->getType())); |
| 338 | CharUnits AlignedElementOffsetInChars = |
| 339 | ElementOffsetInChars.alignTo(ElementAlign); |
| 340 | |
| 341 | if (AlignedElementOffsetInChars > ElementOffsetInChars) { |
| 342 | // We need some padding. |
| 343 | CharUnits NumChars = |
| 344 | AlignedElementOffsetInChars - ElementOffsetInChars; |
| 345 | |
| 346 | llvm::Type *Ty = CGM.Int8Ty; |
| 347 | if (NumChars > CharUnits::One()) |
| 348 | Ty = llvm::ArrayType::get(Ty, NumChars.getQuantity()); |
| 349 | |
| 350 | llvm::Constant *Padding = llvm::UndefValue::get(Ty); |
| 351 | PackedElements.push_back(Padding); |
| 352 | ElementOffsetInChars += getSizeInChars(Padding); |
| 353 | } |
| 354 | |
| 355 | PackedElements.push_back(C); |
| 356 | ElementOffsetInChars += getSizeInChars(C); |
| 357 | } |
| 358 | |
| 359 | assert(ElementOffsetInChars == NextFieldOffsetInChars &&((ElementOffsetInChars == NextFieldOffsetInChars && "Packing the struct changed its size!" ) ? static_cast<void> (0) : __assert_fail ("ElementOffsetInChars == NextFieldOffsetInChars && \"Packing the struct changed its size!\"" , "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 360, __PRETTY_FUNCTION__)) |
| 360 | "Packing the struct changed its size!")((ElementOffsetInChars == NextFieldOffsetInChars && "Packing the struct changed its size!" ) ? static_cast<void> (0) : __assert_fail ("ElementOffsetInChars == NextFieldOffsetInChars && \"Packing the struct changed its size!\"" , "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 360, __PRETTY_FUNCTION__)); |
| 361 | |
| 362 | Elements.swap(PackedElements); |
| 363 | LLVMStructAlignment = CharUnits::One(); |
| 364 | Packed = true; |
| 365 | } |
| 366 | |
| 367 | bool ConstStructBuilder::Build(InitListExpr *ILE) { |
| 368 | RecordDecl *RD = ILE->getType()->getAs<RecordType>()->getDecl(); |
| 369 | const ASTRecordLayout &Layout = CGM.getContext().getASTRecordLayout(RD); |
| 370 | |
| 371 | unsigned FieldNo = 0; |
| 372 | unsigned ElementNo = 0; |
| 373 | |
| 374 | // Bail out if we have base classes. We could support these, but they only |
| 375 | // arise in C++1z where we will have already constant folded most interesting |
| 376 | // cases. FIXME: There are still a few more cases we can handle this way. |
| 377 | if (auto *CXXRD = dyn_cast<CXXRecordDecl>(RD)) |
| 378 | if (CXXRD->getNumBases()) |
| 379 | return false; |
| 380 | |
| 381 | for (RecordDecl::field_iterator Field = RD->field_begin(), |
| 382 | FieldEnd = RD->field_end(); Field != FieldEnd; ++Field, ++FieldNo) { |
| 383 | // If this is a union, skip all the fields that aren't being initialized. |
| 384 | if (RD->isUnion() && ILE->getInitializedFieldInUnion() != *Field) |
| 385 | continue; |
| 386 | |
| 387 | // Don't emit anonymous bitfields, they just affect layout. |
| 388 | if (Field->isUnnamedBitfield()) |
| 389 | continue; |
| 390 | |
| 391 | // Get the initializer. A struct can include fields without initializers, |
| 392 | // we just use explicit null values for them. |
| 393 | llvm::Constant *EltInit; |
| 394 | if (ElementNo < ILE->getNumInits()) |
| 395 | EltInit = Emitter.tryEmitPrivateForMemory(ILE->getInit(ElementNo++), |
| 396 | Field->getType()); |
| 397 | else |
| 398 | EltInit = Emitter.emitNullForMemory(Field->getType()); |
| 399 | |
| 400 | if (!EltInit) |
| 401 | return false; |
| 402 | |
| 403 | if (!Field->isBitField()) { |
| 404 | // Handle non-bitfield members. |
| 405 | AppendField(*Field, Layout.getFieldOffset(FieldNo), EltInit); |
| 406 | } else { |
| 407 | // Otherwise we have a bitfield. |
| 408 | if (auto *CI = dyn_cast<llvm::ConstantInt>(EltInit)) { |
| 409 | AppendBitField(*Field, Layout.getFieldOffset(FieldNo), CI); |
| 410 | } else { |
| 411 | // We are trying to initialize a bitfield with a non-trivial constant, |
| 412 | // this must require run-time code. |
| 413 | return false; |
| 414 | } |
| 415 | } |
| 416 | } |
| 417 | |
| 418 | return true; |
| 419 | } |
| 420 | |
| 421 | namespace { |
| 422 | struct BaseInfo { |
| 423 | BaseInfo(const CXXRecordDecl *Decl, CharUnits Offset, unsigned Index) |
| 424 | : Decl(Decl), Offset(Offset), Index(Index) { |
| 425 | } |
| 426 | |
| 427 | const CXXRecordDecl *Decl; |
| 428 | CharUnits Offset; |
| 429 | unsigned Index; |
| 430 | |
| 431 | bool operator<(const BaseInfo &O) const { return Offset < O.Offset; } |
| 432 | }; |
| 433 | } |
| 434 | |
| 435 | bool ConstStructBuilder::Build(const APValue &Val, const RecordDecl *RD, |
| 436 | bool IsPrimaryBase, |
| 437 | const CXXRecordDecl *VTableClass, |
| 438 | CharUnits Offset) { |
| 439 | const ASTRecordLayout &Layout = CGM.getContext().getASTRecordLayout(RD); |
| 440 | |
| 441 | if (const CXXRecordDecl *CD = dyn_cast<CXXRecordDecl>(RD)) { |
| 442 | // Add a vtable pointer, if we need one and it hasn't already been added. |
| 443 | if (CD->isDynamicClass() && !IsPrimaryBase) { |
| 444 | llvm::Constant *VTableAddressPoint = |
| 445 | CGM.getCXXABI().getVTableAddressPointForConstExpr( |
| 446 | BaseSubobject(CD, Offset), VTableClass); |
| 447 | AppendBytes(Offset, VTableAddressPoint); |
| 448 | } |
| 449 | |
| 450 | // Accumulate and sort bases, in order to visit them in address order, which |
| 451 | // may not be the same as declaration order. |
| 452 | SmallVector<BaseInfo, 8> Bases; |
| 453 | Bases.reserve(CD->getNumBases()); |
| 454 | unsigned BaseNo = 0; |
| 455 | for (CXXRecordDecl::base_class_const_iterator Base = CD->bases_begin(), |
| 456 | BaseEnd = CD->bases_end(); Base != BaseEnd; ++Base, ++BaseNo) { |
| 457 | assert(!Base->isVirtual() && "should not have virtual bases here")((!Base->isVirtual() && "should not have virtual bases here" ) ? static_cast<void> (0) : __assert_fail ("!Base->isVirtual() && \"should not have virtual bases here\"" , "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 457, __PRETTY_FUNCTION__)); |
| 458 | const CXXRecordDecl *BD = Base->getType()->getAsCXXRecordDecl(); |
| 459 | CharUnits BaseOffset = Layout.getBaseClassOffset(BD); |
| 460 | Bases.push_back(BaseInfo(BD, BaseOffset, BaseNo)); |
| 461 | } |
| 462 | llvm::stable_sort(Bases); |
| 463 | |
| 464 | for (unsigned I = 0, N = Bases.size(); I != N; ++I) { |
| 465 | BaseInfo &Base = Bases[I]; |
| 466 | |
| 467 | bool IsPrimaryBase = Layout.getPrimaryBase() == Base.Decl; |
| 468 | Build(Val.getStructBase(Base.Index), Base.Decl, IsPrimaryBase, |
| 469 | VTableClass, Offset + Base.Offset); |
| 470 | } |
| 471 | } |
| 472 | |
| 473 | unsigned FieldNo = 0; |
| 474 | uint64_t OffsetBits = CGM.getContext().toBits(Offset); |
| 475 | |
| 476 | for (RecordDecl::field_iterator Field = RD->field_begin(), |
| 477 | FieldEnd = RD->field_end(); Field != FieldEnd; ++Field, ++FieldNo) { |
| 478 | // If this is a union, skip all the fields that aren't being initialized. |
| 479 | if (RD->isUnion() && Val.getUnionField() != *Field) |
| 480 | continue; |
| 481 | |
| 482 | // Don't emit anonymous bitfields, they just affect layout. |
| 483 | if (Field->isUnnamedBitfield()) |
| 484 | continue; |
| 485 | |
| 486 | // Emit the value of the initializer. |
| 487 | const APValue &FieldValue = |
| 488 | RD->isUnion() ? Val.getUnionValue() : Val.getStructField(FieldNo); |
| 489 | llvm::Constant *EltInit = |
| 490 | Emitter.tryEmitPrivateForMemory(FieldValue, Field->getType()); |
| 491 | if (!EltInit) |
| 492 | return false; |
| 493 | |
| 494 | if (!Field->isBitField()) { |
| 495 | // Handle non-bitfield members. |
| 496 | AppendField(*Field, Layout.getFieldOffset(FieldNo) + OffsetBits, EltInit); |
| 497 | } else { |
| 498 | // Otherwise we have a bitfield. |
| 499 | AppendBitField(*Field, Layout.getFieldOffset(FieldNo) + OffsetBits, |
| 500 | cast<llvm::ConstantInt>(EltInit)); |
| 501 | } |
| 502 | } |
| 503 | |
| 504 | return true; |
| 505 | } |
| 506 | |
| 507 | llvm::Constant *ConstStructBuilder::Finalize(QualType Ty) { |
| 508 | RecordDecl *RD = Ty->getAs<RecordType>()->getDecl(); |
| 509 | const ASTRecordLayout &Layout = CGM.getContext().getASTRecordLayout(RD); |
| 510 | |
| 511 | CharUnits LayoutSizeInChars = Layout.getSize(); |
| 512 | |
| 513 | if (NextFieldOffsetInChars > LayoutSizeInChars) { |
| 514 | // If the struct is bigger than the size of the record type, |
| 515 | // we must have a flexible array member at the end. |
| 516 | assert(RD->hasFlexibleArrayMember() &&((RD->hasFlexibleArrayMember() && "Must have flexible array member if struct is bigger than type!" ) ? static_cast<void> (0) : __assert_fail ("RD->hasFlexibleArrayMember() && \"Must have flexible array member if struct is bigger than type!\"" , "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 517, __PRETTY_FUNCTION__)) |
| 517 | "Must have flexible array member if struct is bigger than type!")((RD->hasFlexibleArrayMember() && "Must have flexible array member if struct is bigger than type!" ) ? static_cast<void> (0) : __assert_fail ("RD->hasFlexibleArrayMember() && \"Must have flexible array member if struct is bigger than type!\"" , "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 517, __PRETTY_FUNCTION__)); |
| 518 | |
| 519 | // No tail padding is necessary. |
| 520 | } else { |
| 521 | // Append tail padding if necessary. |
| 522 | CharUnits LLVMSizeInChars = |
| 523 | NextFieldOffsetInChars.alignTo(LLVMStructAlignment); |
| 524 | |
| 525 | if (LLVMSizeInChars != LayoutSizeInChars) |
| 526 | AppendTailPadding(LayoutSizeInChars); |
| 527 | |
| 528 | LLVMSizeInChars = NextFieldOffsetInChars.alignTo(LLVMStructAlignment); |
| 529 | |
| 530 | // Check if we need to convert the struct to a packed struct. |
| 531 | if (NextFieldOffsetInChars <= LayoutSizeInChars && |
| 532 | LLVMSizeInChars > LayoutSizeInChars) { |
| 533 | assert(!Packed && "Size mismatch!")((!Packed && "Size mismatch!") ? static_cast<void> (0) : __assert_fail ("!Packed && \"Size mismatch!\"" , "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 533, __PRETTY_FUNCTION__)); |
| 534 | |
| 535 | ConvertStructToPacked(); |
| 536 | assert(NextFieldOffsetInChars <= LayoutSizeInChars &&((NextFieldOffsetInChars <= LayoutSizeInChars && "Converting to packed did not help!" ) ? static_cast<void> (0) : __assert_fail ("NextFieldOffsetInChars <= LayoutSizeInChars && \"Converting to packed did not help!\"" , "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 537, __PRETTY_FUNCTION__)) |
| 537 | "Converting to packed did not help!")((NextFieldOffsetInChars <= LayoutSizeInChars && "Converting to packed did not help!" ) ? static_cast<void> (0) : __assert_fail ("NextFieldOffsetInChars <= LayoutSizeInChars && \"Converting to packed did not help!\"" , "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 537, __PRETTY_FUNCTION__)); |
| 538 | } |
| 539 | |
| 540 | LLVMSizeInChars = NextFieldOffsetInChars.alignTo(LLVMStructAlignment); |
| 541 | |
| 542 | assert(LayoutSizeInChars == LLVMSizeInChars &&((LayoutSizeInChars == LLVMSizeInChars && "Tail padding mismatch!" ) ? static_cast<void> (0) : __assert_fail ("LayoutSizeInChars == LLVMSizeInChars && \"Tail padding mismatch!\"" , "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 543, __PRETTY_FUNCTION__)) |
| 543 | "Tail padding mismatch!")((LayoutSizeInChars == LLVMSizeInChars && "Tail padding mismatch!" ) ? static_cast<void> (0) : __assert_fail ("LayoutSizeInChars == LLVMSizeInChars && \"Tail padding mismatch!\"" , "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 543, __PRETTY_FUNCTION__)); |
| 544 | } |
| 545 | |
| 546 | // Pick the type to use. If the type is layout identical to the ConvertType |
| 547 | // type then use it, otherwise use whatever the builder produced for us. |
| 548 | llvm::StructType *STy = |
| 549 | llvm::ConstantStruct::getTypeForElements(CGM.getLLVMContext(), |
| 550 | Elements, Packed); |
| 551 | llvm::Type *ValTy = CGM.getTypes().ConvertType(Ty); |
| 552 | if (llvm::StructType *ValSTy = dyn_cast<llvm::StructType>(ValTy)) { |
| 553 | if (ValSTy->isLayoutIdentical(STy)) |
| 554 | STy = ValSTy; |
| 555 | } |
| 556 | |
| 557 | llvm::Constant *Result = llvm::ConstantStruct::get(STy, Elements); |
| 558 | |
| 559 | assert(NextFieldOffsetInChars.alignTo(getAlignment(Result)) ==((NextFieldOffsetInChars.alignTo(getAlignment(Result)) == getSizeInChars (Result) && "Size mismatch!") ? static_cast<void> (0) : __assert_fail ("NextFieldOffsetInChars.alignTo(getAlignment(Result)) == getSizeInChars(Result) && \"Size mismatch!\"" , "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 561, __PRETTY_FUNCTION__)) |
| 560 | getSizeInChars(Result) &&((NextFieldOffsetInChars.alignTo(getAlignment(Result)) == getSizeInChars (Result) && "Size mismatch!") ? static_cast<void> (0) : __assert_fail ("NextFieldOffsetInChars.alignTo(getAlignment(Result)) == getSizeInChars(Result) && \"Size mismatch!\"" , "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 561, __PRETTY_FUNCTION__)) |
| 561 | "Size mismatch!")((NextFieldOffsetInChars.alignTo(getAlignment(Result)) == getSizeInChars (Result) && "Size mismatch!") ? static_cast<void> (0) : __assert_fail ("NextFieldOffsetInChars.alignTo(getAlignment(Result)) == getSizeInChars(Result) && \"Size mismatch!\"" , "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 561, __PRETTY_FUNCTION__)); |
| 562 | |
| 563 | return Result; |
| 564 | } |
| 565 | |
| 566 | llvm::Constant *ConstStructBuilder::BuildStruct(ConstantEmitter &Emitter, |
| 567 | ConstExprEmitter *ExprEmitter, |
| 568 | llvm::Constant *Base, |
| 569 | InitListExpr *Updater, |
| 570 | QualType ValTy) { |
| 571 | ConstStructBuilder Builder(Emitter); |
| 572 | if (!Builder.Build(ExprEmitter, Base, Updater)) |
| 573 | return nullptr; |
| 574 | return Builder.Finalize(ValTy); |
| 575 | } |
| 576 | |
| 577 | llvm::Constant *ConstStructBuilder::BuildStruct(ConstantEmitter &Emitter, |
| 578 | InitListExpr *ILE, |
| 579 | QualType ValTy) { |
| 580 | ConstStructBuilder Builder(Emitter); |
| 581 | |
| 582 | if (!Builder.Build(ILE)) |
| 583 | return nullptr; |
| 584 | |
| 585 | return Builder.Finalize(ValTy); |
| 586 | } |
| 587 | |
| 588 | llvm::Constant *ConstStructBuilder::BuildStruct(ConstantEmitter &Emitter, |
| 589 | const APValue &Val, |
| 590 | QualType ValTy) { |
| 591 | ConstStructBuilder Builder(Emitter); |
| 592 | |
| 593 | const RecordDecl *RD = ValTy->castAs<RecordType>()->getDecl(); |
| 594 | const CXXRecordDecl *CD = dyn_cast<CXXRecordDecl>(RD); |
| 595 | if (!Builder.Build(Val, RD, false, CD, CharUnits::Zero())) |
| 596 | return nullptr; |
| 597 | |
| 598 | return Builder.Finalize(ValTy); |
| 599 | } |
| 600 | |
| 601 | |
| 602 | //===----------------------------------------------------------------------===// |
| 603 | // ConstExprEmitter |
| 604 | //===----------------------------------------------------------------------===// |
| 605 | |
| 606 | static ConstantAddress tryEmitGlobalCompoundLiteral(CodeGenModule &CGM, |
| 607 | CodeGenFunction *CGF, |
| 608 | const CompoundLiteralExpr *E) { |
| 609 | CharUnits Align = CGM.getContext().getTypeAlignInChars(E->getType()); |
| 610 | if (llvm::GlobalVariable *Addr = |
| 611 | CGM.getAddrOfConstantCompoundLiteralIfEmitted(E)) |
| 612 | return ConstantAddress(Addr, Align); |
| 613 | |
| 614 | LangAS addressSpace = E->getType().getAddressSpace(); |
| 615 | |
| 616 | ConstantEmitter emitter(CGM, CGF); |
| 617 | llvm::Constant *C = emitter.tryEmitForInitializer(E->getInitializer(), |
| 618 | addressSpace, E->getType()); |
| 619 | if (!C) { |
| 620 | assert(!E->isFileScope() &&((!E->isFileScope() && "file-scope compound literal did not have constant initializer!" ) ? static_cast<void> (0) : __assert_fail ("!E->isFileScope() && \"file-scope compound literal did not have constant initializer!\"" , "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 621, __PRETTY_FUNCTION__)) |
| 621 | "file-scope compound literal did not have constant initializer!")((!E->isFileScope() && "file-scope compound literal did not have constant initializer!" ) ? static_cast<void> (0) : __assert_fail ("!E->isFileScope() && \"file-scope compound literal did not have constant initializer!\"" , "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 621, __PRETTY_FUNCTION__)); |
| 622 | return ConstantAddress::invalid(); |
| 623 | } |
| 624 | |
| 625 | auto GV = new llvm::GlobalVariable(CGM.getModule(), C->getType(), |
| 626 | CGM.isTypeConstant(E->getType(), true), |
| 627 | llvm::GlobalValue::InternalLinkage, |
| 628 | C, ".compoundliteral", nullptr, |
| 629 | llvm::GlobalVariable::NotThreadLocal, |
| 630 | CGM.getContext().getTargetAddressSpace(addressSpace)); |
| 631 | emitter.finalize(GV); |
| 632 | GV->setAlignment(Align.getQuantity()); |
| 633 | CGM.setAddrOfConstantCompoundLiteral(E, GV); |
| 634 | return ConstantAddress(GV, Align); |
| 635 | } |
| 636 | |
| 637 | static llvm::Constant * |
| 638 | EmitArrayConstant(CodeGenModule &CGM, const ConstantArrayType *DestType, |
| 639 | llvm::Type *CommonElementType, unsigned ArrayBound, |
| 640 | SmallVectorImpl<llvm::Constant *> &Elements, |
| 641 | llvm::Constant *Filler) { |
| 642 | // Figure out how long the initial prefix of non-zero elements is. |
| 643 | unsigned NonzeroLength = ArrayBound; |
| 644 | if (Elements.size() < NonzeroLength && Filler->isNullValue()) |
| 645 | NonzeroLength = Elements.size(); |
| 646 | if (NonzeroLength == Elements.size()) { |
| 647 | while (NonzeroLength > 0 && Elements[NonzeroLength - 1]->isNullValue()) |
| 648 | --NonzeroLength; |
| 649 | } |
| 650 | |
| 651 | if (NonzeroLength == 0) { |
| 652 | return llvm::ConstantAggregateZero::get( |
| 653 | CGM.getTypes().ConvertType(QualType(DestType, 0))); |
| 654 | } |
| 655 | |
| 656 | // Add a zeroinitializer array filler if we have lots of trailing zeroes. |
| 657 | unsigned TrailingZeroes = ArrayBound - NonzeroLength; |
| 658 | if (TrailingZeroes >= 8) { |
| 659 | assert(Elements.size() >= NonzeroLength &&((Elements.size() >= NonzeroLength && "missing initializer for non-zero element" ) ? static_cast<void> (0) : __assert_fail ("Elements.size() >= NonzeroLength && \"missing initializer for non-zero element\"" , "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 660, __PRETTY_FUNCTION__)) |
| 660 | "missing initializer for non-zero element")((Elements.size() >= NonzeroLength && "missing initializer for non-zero element" ) ? static_cast<void> (0) : __assert_fail ("Elements.size() >= NonzeroLength && \"missing initializer for non-zero element\"" , "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 660, __PRETTY_FUNCTION__)); |
| 661 | |
| 662 | // If all the elements had the same type up to the trailing zeroes, emit a |
| 663 | // struct of two arrays (the nonzero data and the zeroinitializer). |
| 664 | if (CommonElementType && NonzeroLength >= 8) { |
| 665 | llvm::Constant *Initial = llvm::ConstantArray::get( |
| 666 | llvm::ArrayType::get(CommonElementType, NonzeroLength), |
| 667 | makeArrayRef(Elements).take_front(NonzeroLength)); |
| 668 | Elements.resize(2); |
| 669 | Elements[0] = Initial; |
| 670 | } else { |
| 671 | Elements.resize(NonzeroLength + 1); |
| 672 | } |
| 673 | |
| 674 | auto *FillerType = |
| 675 | CommonElementType |
| 676 | ? CommonElementType |
| 677 | : CGM.getTypes().ConvertType(DestType->getElementType()); |
| 678 | FillerType = llvm::ArrayType::get(FillerType, TrailingZeroes); |
| 679 | Elements.back() = llvm::ConstantAggregateZero::get(FillerType); |
| 680 | CommonElementType = nullptr; |
| 681 | } else if (Elements.size() != ArrayBound) { |
| 682 | // Otherwise pad to the right size with the filler if necessary. |
| 683 | Elements.resize(ArrayBound, Filler); |
| 684 | if (Filler->getType() != CommonElementType) |
| 685 | CommonElementType = nullptr; |
| 686 | } |
| 687 | |
| 688 | // If all elements have the same type, just emit an array constant. |
| 689 | if (CommonElementType) |
| 690 | return llvm::ConstantArray::get( |
| 691 | llvm::ArrayType::get(CommonElementType, ArrayBound), Elements); |
| 692 | |
| 693 | // We have mixed types. Use a packed struct. |
| 694 | llvm::SmallVector<llvm::Type *, 16> Types; |
| 695 | Types.reserve(Elements.size()); |
| 696 | for (llvm::Constant *Elt : Elements) |
| 697 | Types.push_back(Elt->getType()); |
| 698 | llvm::StructType *SType = |
| 699 | llvm::StructType::get(CGM.getLLVMContext(), Types, true); |
| 700 | return llvm::ConstantStruct::get(SType, Elements); |
| 701 | } |
| 702 | |
| 703 | // This class only needs to handle arrays, structs and unions. Outside C++11 |
| 704 | // mode, we don't currently constant fold those types. All other types are |
| 705 | // handled by constant folding. |
| 706 | // |
| 707 | // Constant folding is currently missing support for a few features supported |
| 708 | // here: CK_ToUnion, CK_ReinterpretMemberPointer, and DesignatedInitUpdateExpr. |
| 709 | class ConstExprEmitter : |
| 710 | public StmtVisitor<ConstExprEmitter, llvm::Constant*, QualType> { |
| 711 | CodeGenModule &CGM; |
| 712 | ConstantEmitter &Emitter; |
| 713 | llvm::LLVMContext &VMContext; |
| 714 | public: |
| 715 | ConstExprEmitter(ConstantEmitter &emitter) |
| 716 | : CGM(emitter.CGM), Emitter(emitter), VMContext(CGM.getLLVMContext()) { |
| 717 | } |
| 718 | |
| 719 | //===--------------------------------------------------------------------===// |
| 720 | // Visitor Methods |
| 721 | //===--------------------------------------------------------------------===// |
| 722 | |
| 723 | llvm::Constant *VisitStmt(Stmt *S, QualType T) { |
| 724 | return nullptr; |
| 725 | } |
| 726 | |
| 727 | llvm::Constant *VisitConstantExpr(ConstantExpr *CE, QualType T) { |
| 728 | return Visit(CE->getSubExpr(), T); |
| 729 | } |
| 730 | |
| 731 | llvm::Constant *VisitParenExpr(ParenExpr *PE, QualType T) { |
| 732 | return Visit(PE->getSubExpr(), T); |
| 733 | } |
| 734 | |
| 735 | llvm::Constant * |
| 736 | VisitSubstNonTypeTemplateParmExpr(SubstNonTypeTemplateParmExpr *PE, |
| 737 | QualType T) { |
| 738 | return Visit(PE->getReplacement(), T); |
| 739 | } |
| 740 | |
| 741 | llvm::Constant *VisitGenericSelectionExpr(GenericSelectionExpr *GE, |
| 742 | QualType T) { |
| 743 | return Visit(GE->getResultExpr(), T); |
| 744 | } |
| 745 | |
| 746 | llvm::Constant *VisitChooseExpr(ChooseExpr *CE, QualType T) { |
| 747 | return Visit(CE->getChosenSubExpr(), T); |
| 748 | } |
| 749 | |
| 750 | llvm::Constant *VisitCompoundLiteralExpr(CompoundLiteralExpr *E, QualType T) { |
| 751 | return Visit(E->getInitializer(), T); |
| 752 | } |
| 753 | |
| 754 | llvm::Constant *VisitCastExpr(CastExpr *E, QualType destType) { |
| 755 | if (const auto *ECE = dyn_cast<ExplicitCastExpr>(E)) |
| 756 | CGM.EmitExplicitCastExprType(ECE, Emitter.CGF); |
| 757 | Expr *subExpr = E->getSubExpr(); |
| 758 | |
| 759 | switch (E->getCastKind()) { |
| 760 | case CK_ToUnion: { |
| 761 | // GCC cast to union extension |
| 762 | assert(E->getType()->isUnionType() &&((E->getType()->isUnionType() && "Destination type is not union type!" ) ? static_cast<void> (0) : __assert_fail ("E->getType()->isUnionType() && \"Destination type is not union type!\"" , "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 763, __PRETTY_FUNCTION__)) |
| 763 | "Destination type is not union type!")((E->getType()->isUnionType() && "Destination type is not union type!" ) ? static_cast<void> (0) : __assert_fail ("E->getType()->isUnionType() && \"Destination type is not union type!\"" , "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 763, __PRETTY_FUNCTION__)); |
| 764 | |
| 765 | auto field = E->getTargetUnionField(); |
| 766 | |
| 767 | auto C = Emitter.tryEmitPrivateForMemory(subExpr, field->getType()); |
| 768 | if (!C) return nullptr; |
| 769 | |
| 770 | auto destTy = ConvertType(destType); |
| 771 | if (C->getType() == destTy) return C; |
| 772 | |
| 773 | // Build a struct with the union sub-element as the first member, |
| 774 | // and padded to the appropriate size. |
| 775 | SmallVector<llvm::Constant*, 2> Elts; |
| 776 | SmallVector<llvm::Type*, 2> Types; |
| 777 | Elts.push_back(C); |
| 778 | Types.push_back(C->getType()); |
| 779 | unsigned CurSize = CGM.getDataLayout().getTypeAllocSize(C->getType()); |
| 780 | unsigned TotalSize = CGM.getDataLayout().getTypeAllocSize(destTy); |
| 781 | |
| 782 | assert(CurSize <= TotalSize && "Union size mismatch!")((CurSize <= TotalSize && "Union size mismatch!") ? static_cast<void> (0) : __assert_fail ("CurSize <= TotalSize && \"Union size mismatch!\"" , "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 782, __PRETTY_FUNCTION__)); |
| 783 | if (unsigned NumPadBytes = TotalSize - CurSize) { |
| 784 | llvm::Type *Ty = CGM.Int8Ty; |
| 785 | if (NumPadBytes > 1) |
| 786 | Ty = llvm::ArrayType::get(Ty, NumPadBytes); |
| 787 | |
| 788 | Elts.push_back(llvm::UndefValue::get(Ty)); |
| 789 | Types.push_back(Ty); |
| 790 | } |
| 791 | |
| 792 | llvm::StructType *STy = llvm::StructType::get(VMContext, Types, false); |
| 793 | return llvm::ConstantStruct::get(STy, Elts); |
| 794 | } |
| 795 | |
| 796 | case CK_AddressSpaceConversion: { |
| 797 | auto C = Emitter.tryEmitPrivate(subExpr, subExpr->getType()); |
| 798 | if (!C) return nullptr; |
| 799 | LangAS destAS = E->getType()->getPointeeType().getAddressSpace(); |
| 800 | LangAS srcAS = subExpr->getType()->getPointeeType().getAddressSpace(); |
| 801 | llvm::Type *destTy = ConvertType(E->getType()); |
| 802 | return CGM.getTargetCodeGenInfo().performAddrSpaceCast(CGM, C, srcAS, |
| 803 | destAS, destTy); |
| 804 | } |
| 805 | |
| 806 | case CK_LValueToRValue: |
| 807 | case CK_AtomicToNonAtomic: |
| 808 | case CK_NonAtomicToAtomic: |
| 809 | case CK_NoOp: |
| 810 | case CK_ConstructorConversion: |
| 811 | return Visit(subExpr, destType); |
| 812 | |
| 813 | case CK_IntToOCLSampler: |
| 814 | llvm_unreachable("global sampler variables are not generated")::llvm::llvm_unreachable_internal("global sampler variables are not generated" , "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 814); |
| 815 | |
| 816 | case CK_Dependent: llvm_unreachable("saw dependent cast!")::llvm::llvm_unreachable_internal("saw dependent cast!", "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 816); |
| 817 | |
| 818 | case CK_BuiltinFnToFnPtr: |
| 819 | llvm_unreachable("builtin functions are handled elsewhere")::llvm::llvm_unreachable_internal("builtin functions are handled elsewhere" , "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 819); |
| 820 | |
| 821 | case CK_ReinterpretMemberPointer: |
| 822 | case CK_DerivedToBaseMemberPointer: |
| 823 | case CK_BaseToDerivedMemberPointer: { |
| 824 | auto C = Emitter.tryEmitPrivate(subExpr, subExpr->getType()); |
| 825 | if (!C) return nullptr; |
| 826 | return CGM.getCXXABI().EmitMemberPointerConversion(E, C); |
| 827 | } |
| 828 | |
| 829 | // These will never be supported. |
| 830 | case CK_ObjCObjectLValueCast: |
| 831 | case CK_ARCProduceObject: |
| 832 | case CK_ARCConsumeObject: |
| 833 | case CK_ARCReclaimReturnedObject: |
| 834 | case CK_ARCExtendBlockObject: |
| 835 | case CK_CopyAndAutoreleaseBlockObject: |
| 836 | return nullptr; |
| 837 | |
| 838 | // These don't need to be handled here because Evaluate knows how to |
| 839 | // evaluate them in the cases where they can be folded. |
| 840 | case CK_BitCast: |
| 841 | case CK_ToVoid: |
| 842 | case CK_Dynamic: |
| 843 | case CK_LValueBitCast: |
| 844 | case CK_NullToMemberPointer: |
| 845 | case CK_UserDefinedConversion: |
| 846 | case CK_CPointerToObjCPointerCast: |
| 847 | case CK_BlockPointerToObjCPointerCast: |
| 848 | case CK_AnyPointerToBlockPointerCast: |
| 849 | case CK_ArrayToPointerDecay: |
| 850 | case CK_FunctionToPointerDecay: |
| 851 | case CK_BaseToDerived: |
| 852 | case CK_DerivedToBase: |
| 853 | case CK_UncheckedDerivedToBase: |
| 854 | case CK_MemberPointerToBoolean: |
| 855 | case CK_VectorSplat: |
| 856 | case CK_FloatingRealToComplex: |
| 857 | case CK_FloatingComplexToReal: |
| 858 | case CK_FloatingComplexToBoolean: |
| 859 | case CK_FloatingComplexCast: |
| 860 | case CK_FloatingComplexToIntegralComplex: |
| 861 | case CK_IntegralRealToComplex: |
| 862 | case CK_IntegralComplexToReal: |
| 863 | case CK_IntegralComplexToBoolean: |
| 864 | case CK_IntegralComplexCast: |
| 865 | case CK_IntegralComplexToFloatingComplex: |
| 866 | case CK_PointerToIntegral: |
| 867 | case CK_PointerToBoolean: |
| 868 | case CK_NullToPointer: |
| 869 | case CK_IntegralCast: |
| 870 | case CK_BooleanToSignedIntegral: |
| 871 | case CK_IntegralToPointer: |
| 872 | case CK_IntegralToBoolean: |
| 873 | case CK_IntegralToFloating: |
| 874 | case CK_FloatingToIntegral: |
| 875 | case CK_FloatingToBoolean: |
| 876 | case CK_FloatingCast: |
| 877 | case CK_FixedPointCast: |
| 878 | case CK_FixedPointToBoolean: |
| 879 | case CK_FixedPointToIntegral: |
| 880 | case CK_IntegralToFixedPoint: |
| 881 | case CK_ZeroToOCLOpaqueType: |
| 882 | return nullptr; |
| 883 | } |
| 884 | llvm_unreachable("Invalid CastKind")::llvm::llvm_unreachable_internal("Invalid CastKind", "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 884); |
| 885 | } |
| 886 | |
| 887 | llvm::Constant *VisitCXXDefaultArgExpr(CXXDefaultArgExpr *DAE, QualType T) { |
| 888 | return Visit(DAE->getExpr(), T); |
| 889 | } |
| 890 | |
| 891 | llvm::Constant *VisitCXXDefaultInitExpr(CXXDefaultInitExpr *DIE, QualType T) { |
| 892 | // No need for a DefaultInitExprScope: we don't handle 'this' in a |
| 893 | // constant expression. |
| 894 | return Visit(DIE->getExpr(), T); |
| 895 | } |
| 896 | |
| 897 | llvm::Constant *VisitExprWithCleanups(ExprWithCleanups *E, QualType T) { |
| 898 | if (!E->cleanupsHaveSideEffects()) |
| 899 | return Visit(E->getSubExpr(), T); |
| 900 | return nullptr; |
| 901 | } |
| 902 | |
| 903 | llvm::Constant *VisitMaterializeTemporaryExpr(MaterializeTemporaryExpr *E, |
| 904 | QualType T) { |
| 905 | return Visit(E->GetTemporaryExpr(), T); |
| 906 | } |
| 907 | |
| 908 | llvm::Constant *EmitArrayInitialization(InitListExpr *ILE, QualType T) { |
| 909 | auto *CAT = CGM.getContext().getAsConstantArrayType(ILE->getType()); |
| 910 | assert(CAT && "can't emit array init for non-constant-bound array")((CAT && "can't emit array init for non-constant-bound array" ) ? static_cast<void> (0) : __assert_fail ("CAT && \"can't emit array init for non-constant-bound array\"" , "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 910, __PRETTY_FUNCTION__)); |
| 911 | unsigned NumInitElements = ILE->getNumInits(); |
| 912 | unsigned NumElements = CAT->getSize().getZExtValue(); |
| 913 | |
| 914 | // Initialising an array requires us to automatically |
| 915 | // initialise any elements that have not been initialised explicitly |
| 916 | unsigned NumInitableElts = std::min(NumInitElements, NumElements); |
| 917 | |
| 918 | QualType EltType = CAT->getElementType(); |
| 919 | |
| 920 | // Initialize remaining array elements. |
| 921 | llvm::Constant *fillC = nullptr; |
| 922 | if (Expr *filler = ILE->getArrayFiller()) { |
| 923 | fillC = Emitter.tryEmitAbstractForMemory(filler, EltType); |
| 924 | if (!fillC) |
| 925 | return nullptr; |
| 926 | } |
| 927 | |
| 928 | // Copy initializer elements. |
| 929 | SmallVector<llvm::Constant*, 16> Elts; |
| 930 | if (fillC && fillC->isNullValue()) |
| 931 | Elts.reserve(NumInitableElts + 1); |
| 932 | else |
| 933 | Elts.reserve(NumElements); |
| 934 | |
| 935 | llvm::Type *CommonElementType = nullptr; |
| 936 | for (unsigned i = 0; i < NumInitableElts; ++i) { |
| 937 | Expr *Init = ILE->getInit(i); |
| 938 | llvm::Constant *C = Emitter.tryEmitPrivateForMemory(Init, EltType); |
| 939 | if (!C) |
| 940 | return nullptr; |
| 941 | if (i == 0) |
| 942 | CommonElementType = C->getType(); |
| 943 | else if (C->getType() != CommonElementType) |
| 944 | CommonElementType = nullptr; |
| 945 | Elts.push_back(C); |
| 946 | } |
| 947 | |
| 948 | return EmitArrayConstant(CGM, CAT, CommonElementType, NumElements, Elts, |
| 949 | fillC); |
| 950 | } |
| 951 | |
| 952 | llvm::Constant *EmitRecordInitialization(InitListExpr *ILE, QualType T) { |
| 953 | return ConstStructBuilder::BuildStruct(Emitter, ILE, T); |
| 954 | } |
| 955 | |
| 956 | llvm::Constant *VisitImplicitValueInitExpr(ImplicitValueInitExpr* E, |
| 957 | QualType T) { |
| 958 | return CGM.EmitNullConstant(T); |
| 959 | } |
| 960 | |
| 961 | llvm::Constant *VisitInitListExpr(InitListExpr *ILE, QualType T) { |
| 962 | if (ILE->isTransparent()) |
| 963 | return Visit(ILE->getInit(0), T); |
| 964 | |
| 965 | if (ILE->getType()->isArrayType()) |
| 966 | return EmitArrayInitialization(ILE, T); |
| 967 | |
| 968 | if (ILE->getType()->isRecordType()) |
| 969 | return EmitRecordInitialization(ILE, T); |
| 970 | |
| 971 | return nullptr; |
| 972 | } |
| 973 | |
| 974 | llvm::Constant *EmitDesignatedInitUpdater(llvm::Constant *Base, |
| 975 | InitListExpr *Updater, |
| 976 | QualType destType) { |
| 977 | if (auto destAT = CGM.getContext().getAsArrayType(destType)) { |
| 978 | llvm::ArrayType *AType = cast<llvm::ArrayType>(ConvertType(destType)); |
| 979 | llvm::Type *ElemType = AType->getElementType(); |
| 980 | |
| 981 | unsigned NumInitElements = Updater->getNumInits(); |
| 982 | unsigned NumElements = AType->getNumElements(); |
| 983 | |
| 984 | std::vector<llvm::Constant *> Elts; |
| 985 | Elts.reserve(NumElements); |
| 986 | |
| 987 | QualType destElemType = destAT->getElementType(); |
| 988 | |
| 989 | if (auto DataArray = dyn_cast<llvm::ConstantDataArray>(Base)) |
| 990 | for (unsigned i = 0; i != NumElements; ++i) |
| 991 | Elts.push_back(DataArray->getElementAsConstant(i)); |
| 992 | else if (auto Array = dyn_cast<llvm::ConstantArray>(Base)) |
| 993 | for (unsigned i = 0; i != NumElements; ++i) |
| 994 | Elts.push_back(Array->getOperand(i)); |
| 995 | else |
| 996 | return nullptr; // FIXME: other array types not implemented |
| 997 | |
| 998 | llvm::Constant *fillC = nullptr; |
| 999 | if (Expr *filler = Updater->getArrayFiller()) |
| 1000 | if (!isa<NoInitExpr>(filler)) |
| 1001 | fillC = Emitter.tryEmitAbstractForMemory(filler, destElemType); |
| 1002 | bool RewriteType = (fillC && fillC->getType() != ElemType); |
| 1003 | |
| 1004 | for (unsigned i = 0; i != NumElements; ++i) { |
| 1005 | Expr *Init = nullptr; |
| 1006 | if (i < NumInitElements) |
| 1007 | Init = Updater->getInit(i); |
| 1008 | |
| 1009 | if (!Init && fillC) |
| 1010 | Elts[i] = fillC; |
| 1011 | else if (!Init || isa<NoInitExpr>(Init)) |
| 1012 | ; // Do nothing. |
| 1013 | else if (InitListExpr *ChildILE = dyn_cast<InitListExpr>(Init)) |
| 1014 | Elts[i] = EmitDesignatedInitUpdater(Elts[i], ChildILE, destElemType); |
| 1015 | else |
| 1016 | Elts[i] = Emitter.tryEmitPrivateForMemory(Init, destElemType); |
| 1017 | |
| 1018 | if (!Elts[i]) |
| 1019 | return nullptr; |
| 1020 | RewriteType |= (Elts[i]->getType() != ElemType); |
| 1021 | } |
| 1022 | |
| 1023 | if (RewriteType) { |
| 1024 | std::vector<llvm::Type *> Types; |
| 1025 | Types.reserve(NumElements); |
| 1026 | for (unsigned i = 0; i != NumElements; ++i) |
| 1027 | Types.push_back(Elts[i]->getType()); |
| 1028 | llvm::StructType *SType = llvm::StructType::get(AType->getContext(), |
| 1029 | Types, true); |
| 1030 | return llvm::ConstantStruct::get(SType, Elts); |
| 1031 | } |
| 1032 | |
| 1033 | return llvm::ConstantArray::get(AType, Elts); |
| 1034 | } |
| 1035 | |
| 1036 | if (destType->isRecordType()) |
| 1037 | return ConstStructBuilder::BuildStruct(Emitter, this, Base, Updater, |
| 1038 | destType); |
| 1039 | |
| 1040 | return nullptr; |
| 1041 | } |
| 1042 | |
| 1043 | llvm::Constant *VisitDesignatedInitUpdateExpr(DesignatedInitUpdateExpr *E, |
| 1044 | QualType destType) { |
| 1045 | auto C = Visit(E->getBase(), destType); |
| 1046 | if (!C) return nullptr; |
| 1047 | return EmitDesignatedInitUpdater(C, E->getUpdater(), destType); |
| 1048 | } |
| 1049 | |
| 1050 | llvm::Constant *VisitCXXConstructExpr(CXXConstructExpr *E, QualType Ty) { |
| 1051 | if (!E->getConstructor()->isTrivial()) |
| 1052 | return nullptr; |
| 1053 | |
| 1054 | // FIXME: We should not have to call getBaseElementType here. |
| 1055 | const RecordType *RT = |
| 1056 | CGM.getContext().getBaseElementType(Ty)->getAs<RecordType>(); |
| 1057 | const CXXRecordDecl *RD = cast<CXXRecordDecl>(RT->getDecl()); |
| 1058 | |
| 1059 | // If the class doesn't have a trivial destructor, we can't emit it as a |
| 1060 | // constant expr. |
| 1061 | if (!RD->hasTrivialDestructor()) |
| 1062 | return nullptr; |
| 1063 | |
| 1064 | // Only copy and default constructors can be trivial. |
| 1065 | |
| 1066 | |
| 1067 | if (E->getNumArgs()) { |
| 1068 | assert(E->getNumArgs() == 1 && "trivial ctor with > 1 argument")((E->getNumArgs() == 1 && "trivial ctor with > 1 argument" ) ? static_cast<void> (0) : __assert_fail ("E->getNumArgs() == 1 && \"trivial ctor with > 1 argument\"" , "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 1068, __PRETTY_FUNCTION__)); |
| 1069 | assert(E->getConstructor()->isCopyOrMoveConstructor() &&((E->getConstructor()->isCopyOrMoveConstructor() && "trivial ctor has argument but isn't a copy/move ctor") ? static_cast <void> (0) : __assert_fail ("E->getConstructor()->isCopyOrMoveConstructor() && \"trivial ctor has argument but isn't a copy/move ctor\"" , "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 1070, __PRETTY_FUNCTION__)) |
| 1070 | "trivial ctor has argument but isn't a copy/move ctor")((E->getConstructor()->isCopyOrMoveConstructor() && "trivial ctor has argument but isn't a copy/move ctor") ? static_cast <void> (0) : __assert_fail ("E->getConstructor()->isCopyOrMoveConstructor() && \"trivial ctor has argument but isn't a copy/move ctor\"" , "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 1070, __PRETTY_FUNCTION__)); |
| 1071 | |
| 1072 | Expr *Arg = E->getArg(0); |
| 1073 | assert(CGM.getContext().hasSameUnqualifiedType(Ty, Arg->getType()) &&((CGM.getContext().hasSameUnqualifiedType(Ty, Arg->getType ()) && "argument to copy ctor is of wrong type") ? static_cast <void> (0) : __assert_fail ("CGM.getContext().hasSameUnqualifiedType(Ty, Arg->getType()) && \"argument to copy ctor is of wrong type\"" , "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 1074, __PRETTY_FUNCTION__)) |
| 1074 | "argument to copy ctor is of wrong type")((CGM.getContext().hasSameUnqualifiedType(Ty, Arg->getType ()) && "argument to copy ctor is of wrong type") ? static_cast <void> (0) : __assert_fail ("CGM.getContext().hasSameUnqualifiedType(Ty, Arg->getType()) && \"argument to copy ctor is of wrong type\"" , "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 1074, __PRETTY_FUNCTION__)); |
| 1075 | |
| 1076 | return Visit(Arg, Ty); |
| 1077 | } |
| 1078 | |
| 1079 | return CGM.EmitNullConstant(Ty); |
| 1080 | } |
| 1081 | |
| 1082 | llvm::Constant *VisitStringLiteral(StringLiteral *E, QualType T) { |
| 1083 | // This is a string literal initializing an array in an initializer. |
| 1084 | return CGM.GetConstantArrayFromStringLiteral(E); |
| 1085 | } |
| 1086 | |
| 1087 | llvm::Constant *VisitObjCEncodeExpr(ObjCEncodeExpr *E, QualType T) { |
| 1088 | // This must be an @encode initializing an array in a static initializer. |
| 1089 | // Don't emit it as the address of the string, emit the string data itself |
| 1090 | // as an inline array. |
| 1091 | std::string Str; |
| 1092 | CGM.getContext().getObjCEncodingForType(E->getEncodedType(), Str); |
| 1093 | const ConstantArrayType *CAT = CGM.getContext().getAsConstantArrayType(T); |
| 1094 | |
| 1095 | // Resize the string to the right size, adding zeros at the end, or |
| 1096 | // truncating as needed. |
| 1097 | Str.resize(CAT->getSize().getZExtValue(), '\0'); |
| 1098 | return llvm::ConstantDataArray::getString(VMContext, Str, false); |
| 1099 | } |
| 1100 | |
| 1101 | llvm::Constant *VisitUnaryExtension(const UnaryOperator *E, QualType T) { |
| 1102 | return Visit(E->getSubExpr(), T); |
| 1103 | } |
| 1104 | |
| 1105 | // Utility methods |
| 1106 | llvm::Type *ConvertType(QualType T) { |
| 1107 | return CGM.getTypes().ConvertType(T); |
| 1108 | } |
| 1109 | }; |
| 1110 | |
| 1111 | } // end anonymous namespace. |
| 1112 | |
| 1113 | bool ConstStructBuilder::Build(ConstExprEmitter *ExprEmitter, |
| 1114 | llvm::Constant *Base, |
| 1115 | InitListExpr *Updater) { |
| 1116 | assert(Base && "base expression should not be empty")((Base && "base expression should not be empty") ? static_cast <void> (0) : __assert_fail ("Base && \"base expression should not be empty\"" , "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 1116, __PRETTY_FUNCTION__)); |
| 1117 | |
| 1118 | QualType ExprType = Updater->getType(); |
| 1119 | RecordDecl *RD = ExprType->getAs<RecordType>()->getDecl(); |
| 1120 | const ASTRecordLayout &Layout = CGM.getContext().getASTRecordLayout(RD); |
| 1121 | const llvm::StructLayout *BaseLayout = CGM.getDataLayout().getStructLayout( |
| 1122 | cast<llvm::StructType>(Base->getType())); |
| 1123 | unsigned FieldNo = -1; |
| 1124 | unsigned ElementNo = 0; |
| 1125 | |
| 1126 | // Bail out if we have base classes. We could support these, but they only |
| 1127 | // arise in C++1z where we will have already constant folded most interesting |
| 1128 | // cases. FIXME: There are still a few more cases we can handle this way. |
| 1129 | if (auto *CXXRD = dyn_cast<CXXRecordDecl>(RD)) |
| 1130 | if (CXXRD->getNumBases()) |
| 1131 | return false; |
| 1132 | |
| 1133 | for (FieldDecl *Field : RD->fields()) { |
| 1134 | ++FieldNo; |
| 1135 | |
| 1136 | if (RD->isUnion() && Updater->getInitializedFieldInUnion() != Field) |
| 1137 | continue; |
| 1138 | |
| 1139 | // Skip anonymous bitfields. |
| 1140 | if (Field->isUnnamedBitfield()) |
| 1141 | continue; |
| 1142 | |
| 1143 | llvm::Constant *EltInit = Base->getAggregateElement(ElementNo); |
| 1144 | |
| 1145 | // Bail out if the type of the ConstantStruct does not have the same layout |
| 1146 | // as the type of the InitListExpr. |
| 1147 | if (CGM.getTypes().ConvertType(Field->getType()) != EltInit->getType() || |
| 1148 | Layout.getFieldOffset(ElementNo) != |
| 1149 | BaseLayout->getElementOffsetInBits(ElementNo)) |
| 1150 | return false; |
| 1151 | |
| 1152 | // Get the initializer. If we encounter an empty field or a NoInitExpr, |
| 1153 | // we use values from the base expression. |
| 1154 | Expr *Init = nullptr; |
| 1155 | if (ElementNo < Updater->getNumInits()) |
| 1156 | Init = Updater->getInit(ElementNo); |
| 1157 | |
| 1158 | if (!Init || isa<NoInitExpr>(Init)) |
| 1159 | ; // Do nothing. |
| 1160 | else if (InitListExpr *ChildILE = dyn_cast<InitListExpr>(Init)) |
| 1161 | EltInit = ExprEmitter->EmitDesignatedInitUpdater(EltInit, ChildILE, |
| 1162 | Field->getType()); |
| 1163 | else |
| 1164 | EltInit = Emitter.tryEmitPrivateForMemory(Init, Field->getType()); |
| 1165 | |
| 1166 | ++ElementNo; |
| 1167 | |
| 1168 | if (!EltInit) |
| 1169 | return false; |
| 1170 | |
| 1171 | if (!Field->isBitField()) |
| 1172 | AppendField(Field, Layout.getFieldOffset(FieldNo), EltInit); |
| 1173 | else if (llvm::ConstantInt *CI = dyn_cast<llvm::ConstantInt>(EltInit)) |
| 1174 | AppendBitField(Field, Layout.getFieldOffset(FieldNo), CI); |
| 1175 | else |
| 1176 | // Initializing a bitfield with a non-trivial constant? |
| 1177 | return false; |
| 1178 | } |
| 1179 | |
| 1180 | return true; |
| 1181 | } |
| 1182 | |
| 1183 | llvm::Constant *ConstantEmitter::validateAndPopAbstract(llvm::Constant *C, |
| 1184 | AbstractState saved) { |
| 1185 | Abstract = saved.OldValue; |
| 1186 | |
| 1187 | assert(saved.OldPlaceholdersSize == PlaceholderAddresses.size() &&((saved.OldPlaceholdersSize == PlaceholderAddresses.size() && "created a placeholder while doing an abstract emission?") ? static_cast<void> (0) : __assert_fail ("saved.OldPlaceholdersSize == PlaceholderAddresses.size() && \"created a placeholder while doing an abstract emission?\"" , "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 1188, __PRETTY_FUNCTION__)) |
| 1188 | "created a placeholder while doing an abstract emission?")((saved.OldPlaceholdersSize == PlaceholderAddresses.size() && "created a placeholder while doing an abstract emission?") ? static_cast<void> (0) : __assert_fail ("saved.OldPlaceholdersSize == PlaceholderAddresses.size() && \"created a placeholder while doing an abstract emission?\"" , "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 1188, __PRETTY_FUNCTION__)); |
| 1189 | |
| 1190 | // No validation necessary for now. |
| 1191 | // No cleanup to do for now. |
| 1192 | return C; |
| 1193 | } |
| 1194 | |
| 1195 | llvm::Constant * |
| 1196 | ConstantEmitter::tryEmitAbstractForInitializer(const VarDecl &D) { |
| 1197 | auto state = pushAbstract(); |
| 1198 | auto C = tryEmitPrivateForVarInit(D); |
| 1199 | return validateAndPopAbstract(C, state); |
| 1200 | } |
| 1201 | |
| 1202 | llvm::Constant * |
| 1203 | ConstantEmitter::tryEmitAbstract(const Expr *E, QualType destType) { |
| 1204 | auto state = pushAbstract(); |
| 1205 | auto C = tryEmitPrivate(E, destType); |
| 1206 | return validateAndPopAbstract(C, state); |
| 1207 | } |
| 1208 | |
| 1209 | llvm::Constant * |
| 1210 | ConstantEmitter::tryEmitAbstract(const APValue &value, QualType destType) { |
| 1211 | auto state = pushAbstract(); |
| 1212 | auto C = tryEmitPrivate(value, destType); |
| 1213 | return validateAndPopAbstract(C, state); |
| 1214 | } |
| 1215 | |
| 1216 | llvm::Constant * |
| 1217 | ConstantEmitter::emitAbstract(const Expr *E, QualType destType) { |
| 1218 | auto state = pushAbstract(); |
| 1219 | auto C = tryEmitPrivate(E, destType); |
| 1220 | C = validateAndPopAbstract(C, state); |
| 1221 | if (!C) { |
| 1222 | CGM.Error(E->getExprLoc(), |
| 1223 | "internal error: could not emit constant value \"abstractly\""); |
| 1224 | C = CGM.EmitNullConstant(destType); |
| 1225 | } |
| 1226 | return C; |
| 1227 | } |
| 1228 | |
| 1229 | llvm::Constant * |
| 1230 | ConstantEmitter::emitAbstract(SourceLocation loc, const APValue &value, |
| 1231 | QualType destType) { |
| 1232 | auto state = pushAbstract(); |
| 1233 | auto C = tryEmitPrivate(value, destType); |
| 1234 | C = validateAndPopAbstract(C, state); |
| 1235 | if (!C) { |
| 1236 | CGM.Error(loc, |
| 1237 | "internal error: could not emit constant value \"abstractly\""); |
| 1238 | C = CGM.EmitNullConstant(destType); |
| 1239 | } |
| 1240 | return C; |
| 1241 | } |
| 1242 | |
| 1243 | llvm::Constant *ConstantEmitter::tryEmitForInitializer(const VarDecl &D) { |
| 1244 | initializeNonAbstract(D.getType().getAddressSpace()); |
| 1245 | return markIfFailed(tryEmitPrivateForVarInit(D)); |
| 1246 | } |
| 1247 | |
| 1248 | llvm::Constant *ConstantEmitter::tryEmitForInitializer(const Expr *E, |
| 1249 | LangAS destAddrSpace, |
| 1250 | QualType destType) { |
| 1251 | initializeNonAbstract(destAddrSpace); |
| 1252 | return markIfFailed(tryEmitPrivateForMemory(E, destType)); |
| 1253 | } |
| 1254 | |
| 1255 | llvm::Constant *ConstantEmitter::emitForInitializer(const APValue &value, |
| 1256 | LangAS destAddrSpace, |
| 1257 | QualType destType) { |
| 1258 | initializeNonAbstract(destAddrSpace); |
| 1259 | auto C = tryEmitPrivateForMemory(value, destType); |
| 1260 | assert(C && "couldn't emit constant value non-abstractly?")((C && "couldn't emit constant value non-abstractly?" ) ? static_cast<void> (0) : __assert_fail ("C && \"couldn't emit constant value non-abstractly?\"" , "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 1260, __PRETTY_FUNCTION__)); |
| 1261 | return C; |
| 1262 | } |
| 1263 | |
| 1264 | llvm::GlobalValue *ConstantEmitter::getCurrentAddrPrivate() { |
| 1265 | assert(!Abstract && "cannot get current address for abstract constant")((!Abstract && "cannot get current address for abstract constant" ) ? static_cast<void> (0) : __assert_fail ("!Abstract && \"cannot get current address for abstract constant\"" , "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 1265, __PRETTY_FUNCTION__)); |
| 1266 | |
| 1267 | |
| 1268 | |
| 1269 | // Make an obviously ill-formed global that should blow up compilation |
| 1270 | // if it survives. |
| 1271 | auto global = new llvm::GlobalVariable(CGM.getModule(), CGM.Int8Ty, true, |
| 1272 | llvm::GlobalValue::PrivateLinkage, |
| 1273 | /*init*/ nullptr, |
| 1274 | /*name*/ "", |
| 1275 | /*before*/ nullptr, |
| 1276 | llvm::GlobalVariable::NotThreadLocal, |
| 1277 | CGM.getContext().getTargetAddressSpace(DestAddressSpace)); |
| 1278 | |
| 1279 | PlaceholderAddresses.push_back(std::make_pair(nullptr, global)); |
| 1280 | |
| 1281 | return global; |
| 1282 | } |
| 1283 | |
| 1284 | void ConstantEmitter::registerCurrentAddrPrivate(llvm::Constant *signal, |
| 1285 | llvm::GlobalValue *placeholder) { |
| 1286 | assert(!PlaceholderAddresses.empty())((!PlaceholderAddresses.empty()) ? static_cast<void> (0 ) : __assert_fail ("!PlaceholderAddresses.empty()", "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 1286, __PRETTY_FUNCTION__)); |
| 1287 | assert(PlaceholderAddresses.back().first == nullptr)((PlaceholderAddresses.back().first == nullptr) ? static_cast <void> (0) : __assert_fail ("PlaceholderAddresses.back().first == nullptr" , "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 1287, __PRETTY_FUNCTION__)); |
| 1288 | assert(PlaceholderAddresses.back().second == placeholder)((PlaceholderAddresses.back().second == placeholder) ? static_cast <void> (0) : __assert_fail ("PlaceholderAddresses.back().second == placeholder" , "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 1288, __PRETTY_FUNCTION__)); |
| 1289 | PlaceholderAddresses.back().first = signal; |
| 1290 | } |
| 1291 | |
| 1292 | namespace { |
| 1293 | struct ReplacePlaceholders { |
| 1294 | CodeGenModule &CGM; |
| 1295 | |
| 1296 | /// The base address of the global. |
| 1297 | llvm::Constant *Base; |
| 1298 | llvm::Type *BaseValueTy = nullptr; |
| 1299 | |
| 1300 | /// The placeholder addresses that were registered during emission. |
| 1301 | llvm::DenseMap<llvm::Constant*, llvm::GlobalVariable*> PlaceholderAddresses; |
| 1302 | |
| 1303 | /// The locations of the placeholder signals. |
| 1304 | llvm::DenseMap<llvm::GlobalVariable*, llvm::Constant*> Locations; |
| 1305 | |
| 1306 | /// The current index stack. We use a simple unsigned stack because |
| 1307 | /// we assume that placeholders will be relatively sparse in the |
| 1308 | /// initializer, but we cache the index values we find just in case. |
| 1309 | llvm::SmallVector<unsigned, 8> Indices; |
| 1310 | llvm::SmallVector<llvm::Constant*, 8> IndexValues; |
| 1311 | |
| 1312 | ReplacePlaceholders(CodeGenModule &CGM, llvm::Constant *base, |
| 1313 | ArrayRef<std::pair<llvm::Constant*, |
| 1314 | llvm::GlobalVariable*>> addresses) |
| 1315 | : CGM(CGM), Base(base), |
| 1316 | PlaceholderAddresses(addresses.begin(), addresses.end()) { |
| 1317 | } |
| 1318 | |
| 1319 | void replaceInInitializer(llvm::Constant *init) { |
| 1320 | // Remember the type of the top-most initializer. |
| 1321 | BaseValueTy = init->getType(); |
| 1322 | |
| 1323 | // Initialize the stack. |
| 1324 | Indices.push_back(0); |
| 1325 | IndexValues.push_back(nullptr); |
| 1326 | |
| 1327 | // Recurse into the initializer. |
| 1328 | findLocations(init); |
| 1329 | |
| 1330 | // Check invariants. |
| 1331 | assert(IndexValues.size() == Indices.size() && "mismatch")((IndexValues.size() == Indices.size() && "mismatch") ? static_cast<void> (0) : __assert_fail ("IndexValues.size() == Indices.size() && \"mismatch\"" , "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 1331, __PRETTY_FUNCTION__)); |
| 1332 | assert(Indices.size() == 1 && "didn't pop all indices")((Indices.size() == 1 && "didn't pop all indices") ? static_cast <void> (0) : __assert_fail ("Indices.size() == 1 && \"didn't pop all indices\"" , "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 1332, __PRETTY_FUNCTION__)); |
| 1333 | |
| 1334 | // Do the replacement; this basically invalidates 'init'. |
| 1335 | assert(Locations.size() == PlaceholderAddresses.size() &&((Locations.size() == PlaceholderAddresses.size() && "missed a placeholder?" ) ? static_cast<void> (0) : __assert_fail ("Locations.size() == PlaceholderAddresses.size() && \"missed a placeholder?\"" , "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 1336, __PRETTY_FUNCTION__)) |
| 1336 | "missed a placeholder?")((Locations.size() == PlaceholderAddresses.size() && "missed a placeholder?" ) ? static_cast<void> (0) : __assert_fail ("Locations.size() == PlaceholderAddresses.size() && \"missed a placeholder?\"" , "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 1336, __PRETTY_FUNCTION__)); |
| 1337 | |
| 1338 | // We're iterating over a hashtable, so this would be a source of |
| 1339 | // non-determinism in compiler output *except* that we're just |
| 1340 | // messing around with llvm::Constant structures, which never itself |
| 1341 | // does anything that should be visible in compiler output. |
| 1342 | for (auto &entry : Locations) { |
| 1343 | assert(entry.first->getParent() == nullptr && "not a placeholder!")((entry.first->getParent() == nullptr && "not a placeholder!" ) ? static_cast<void> (0) : __assert_fail ("entry.first->getParent() == nullptr && \"not a placeholder!\"" , "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 1343, __PRETTY_FUNCTION__)); |
| 1344 | entry.first->replaceAllUsesWith(entry.second); |
| 1345 | entry.first->eraseFromParent(); |
| 1346 | } |
| 1347 | } |
| 1348 | |
| 1349 | private: |
| 1350 | void findLocations(llvm::Constant *init) { |
| 1351 | // Recurse into aggregates. |
| 1352 | if (auto agg = dyn_cast<llvm::ConstantAggregate>(init)) { |
| 1353 | for (unsigned i = 0, e = agg->getNumOperands(); i != e; ++i) { |
| 1354 | Indices.push_back(i); |
| 1355 | IndexValues.push_back(nullptr); |
| 1356 | |
| 1357 | findLocations(agg->getOperand(i)); |
| 1358 | |
| 1359 | IndexValues.pop_back(); |
| 1360 | Indices.pop_back(); |
| 1361 | } |
| 1362 | return; |
| 1363 | } |
| 1364 | |
| 1365 | // Otherwise, check for registered constants. |
| 1366 | while (true) { |
| 1367 | auto it = PlaceholderAddresses.find(init); |
| 1368 | if (it != PlaceholderAddresses.end()) { |
| 1369 | setLocation(it->second); |
| 1370 | break; |
| 1371 | } |
| 1372 | |
| 1373 | // Look through bitcasts or other expressions. |
| 1374 | if (auto expr = dyn_cast<llvm::ConstantExpr>(init)) { |
| 1375 | init = expr->getOperand(0); |
| 1376 | } else { |
| 1377 | break; |
| 1378 | } |
| 1379 | } |
| 1380 | } |
| 1381 | |
| 1382 | void setLocation(llvm::GlobalVariable *placeholder) { |
| 1383 | assert(Locations.find(placeholder) == Locations.end() &&((Locations.find(placeholder) == Locations.end() && "already found location for placeholder!" ) ? static_cast<void> (0) : __assert_fail ("Locations.find(placeholder) == Locations.end() && \"already found location for placeholder!\"" , "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 1384, __PRETTY_FUNCTION__)) |
| 1384 | "already found location for placeholder!")((Locations.find(placeholder) == Locations.end() && "already found location for placeholder!" ) ? static_cast<void> (0) : __assert_fail ("Locations.find(placeholder) == Locations.end() && \"already found location for placeholder!\"" , "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 1384, __PRETTY_FUNCTION__)); |
| 1385 | |
| 1386 | // Lazily fill in IndexValues with the values from Indices. |
| 1387 | // We do this in reverse because we should always have a strict |
| 1388 | // prefix of indices from the start. |
| 1389 | assert(Indices.size() == IndexValues.size())((Indices.size() == IndexValues.size()) ? static_cast<void > (0) : __assert_fail ("Indices.size() == IndexValues.size()" , "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 1389, __PRETTY_FUNCTION__)); |
| 1390 | for (size_t i = Indices.size() - 1; i != size_t(-1); --i) { |
| 1391 | if (IndexValues[i]) { |
| 1392 | #ifndef NDEBUG |
| 1393 | for (size_t j = 0; j != i + 1; ++j) { |
| 1394 | assert(IndexValues[j] &&((IndexValues[j] && isa<llvm::ConstantInt>(IndexValues [j]) && cast<llvm::ConstantInt>(IndexValues[j]) ->getZExtValue() == Indices[j]) ? static_cast<void> ( 0) : __assert_fail ("IndexValues[j] && isa<llvm::ConstantInt>(IndexValues[j]) && cast<llvm::ConstantInt>(IndexValues[j])->getZExtValue() == Indices[j]" , "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 1397, __PRETTY_FUNCTION__)) |
| 1395 | isa<llvm::ConstantInt>(IndexValues[j]) &&((IndexValues[j] && isa<llvm::ConstantInt>(IndexValues [j]) && cast<llvm::ConstantInt>(IndexValues[j]) ->getZExtValue() == Indices[j]) ? static_cast<void> ( 0) : __assert_fail ("IndexValues[j] && isa<llvm::ConstantInt>(IndexValues[j]) && cast<llvm::ConstantInt>(IndexValues[j])->getZExtValue() == Indices[j]" , "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 1397, __PRETTY_FUNCTION__)) |
| 1396 | cast<llvm::ConstantInt>(IndexValues[j])->getZExtValue()((IndexValues[j] && isa<llvm::ConstantInt>(IndexValues [j]) && cast<llvm::ConstantInt>(IndexValues[j]) ->getZExtValue() == Indices[j]) ? static_cast<void> ( 0) : __assert_fail ("IndexValues[j] && isa<llvm::ConstantInt>(IndexValues[j]) && cast<llvm::ConstantInt>(IndexValues[j])->getZExtValue() == Indices[j]" , "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 1397, __PRETTY_FUNCTION__)) |
| 1397 | == Indices[j])((IndexValues[j] && isa<llvm::ConstantInt>(IndexValues [j]) && cast<llvm::ConstantInt>(IndexValues[j]) ->getZExtValue() == Indices[j]) ? static_cast<void> ( 0) : __assert_fail ("IndexValues[j] && isa<llvm::ConstantInt>(IndexValues[j]) && cast<llvm::ConstantInt>(IndexValues[j])->getZExtValue() == Indices[j]" , "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 1397, __PRETTY_FUNCTION__)); |
| 1398 | } |
| 1399 | #endif |
| 1400 | break; |
| 1401 | } |
| 1402 | |
| 1403 | IndexValues[i] = llvm::ConstantInt::get(CGM.Int32Ty, Indices[i]); |
| 1404 | } |
| 1405 | |
| 1406 | // Form a GEP and then bitcast to the placeholder type so that the |
| 1407 | // replacement will succeed. |
| 1408 | llvm::Constant *location = |
| 1409 | llvm::ConstantExpr::getInBoundsGetElementPtr(BaseValueTy, |
| 1410 | Base, IndexValues); |
| 1411 | location = llvm::ConstantExpr::getBitCast(location, |
| 1412 | placeholder->getType()); |
| 1413 | |
| 1414 | Locations.insert({placeholder, location}); |
| 1415 | } |
| 1416 | }; |
| 1417 | } |
| 1418 | |
| 1419 | void ConstantEmitter::finalize(llvm::GlobalVariable *global) { |
| 1420 | assert(InitializedNonAbstract &&((InitializedNonAbstract && "finalizing emitter that was used for abstract emission?" ) ? static_cast<void> (0) : __assert_fail ("InitializedNonAbstract && \"finalizing emitter that was used for abstract emission?\"" , "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 1421, __PRETTY_FUNCTION__)) |
| 1421 | "finalizing emitter that was used for abstract emission?")((InitializedNonAbstract && "finalizing emitter that was used for abstract emission?" ) ? static_cast<void> (0) : __assert_fail ("InitializedNonAbstract && \"finalizing emitter that was used for abstract emission?\"" , "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 1421, __PRETTY_FUNCTION__)); |
| 1422 | assert(!Finalized && "finalizing emitter multiple times")((!Finalized && "finalizing emitter multiple times") ? static_cast<void> (0) : __assert_fail ("!Finalized && \"finalizing emitter multiple times\"" , "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 1422, __PRETTY_FUNCTION__)); |
| 1423 | assert(global->getInitializer())((global->getInitializer()) ? static_cast<void> (0) : __assert_fail ("global->getInitializer()", "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 1423, __PRETTY_FUNCTION__)); |
| 1424 | |
| 1425 | // Note that we might also be Failed. |
| 1426 | Finalized = true; |
| 1427 | |
| 1428 | if (!PlaceholderAddresses.empty()) { |
| 1429 | ReplacePlaceholders(CGM, global, PlaceholderAddresses) |
| 1430 | .replaceInInitializer(global->getInitializer()); |
| 1431 | PlaceholderAddresses.clear(); // satisfy |
| 1432 | } |
| 1433 | } |
| 1434 | |
| 1435 | ConstantEmitter::~ConstantEmitter() { |
| 1436 | assert((!InitializedNonAbstract || Finalized || Failed) &&(((!InitializedNonAbstract || Finalized || Failed) && "not finalized after being initialized for non-abstract emission" ) ? static_cast<void> (0) : __assert_fail ("(!InitializedNonAbstract || Finalized || Failed) && \"not finalized after being initialized for non-abstract emission\"" , "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 1437, __PRETTY_FUNCTION__)) |
| 1437 | "not finalized after being initialized for non-abstract emission")(((!InitializedNonAbstract || Finalized || Failed) && "not finalized after being initialized for non-abstract emission" ) ? static_cast<void> (0) : __assert_fail ("(!InitializedNonAbstract || Finalized || Failed) && \"not finalized after being initialized for non-abstract emission\"" , "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 1437, __PRETTY_FUNCTION__)); |
| 1438 | assert(PlaceholderAddresses.empty() && "unhandled placeholders")((PlaceholderAddresses.empty() && "unhandled placeholders" ) ? static_cast<void> (0) : __assert_fail ("PlaceholderAddresses.empty() && \"unhandled placeholders\"" , "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 1438, __PRETTY_FUNCTION__)); |
| 1439 | } |
| 1440 | |
| 1441 | static QualType getNonMemoryType(CodeGenModule &CGM, QualType type) { |
| 1442 | if (auto AT = type->getAs<AtomicType>()) { |
| 1443 | return CGM.getContext().getQualifiedType(AT->getValueType(), |
| 1444 | type.getQualifiers()); |
| 1445 | } |
| 1446 | return type; |
| 1447 | } |
| 1448 | |
| 1449 | llvm::Constant *ConstantEmitter::tryEmitPrivateForVarInit(const VarDecl &D) { |
| 1450 | // Make a quick check if variable can be default NULL initialized |
| 1451 | // and avoid going through rest of code which may do, for c++11, |
| 1452 | // initialization of memory to all NULLs. |
| 1453 | if (!D.hasLocalStorage()) { |
| 1454 | QualType Ty = CGM.getContext().getBaseElementType(D.getType()); |
| 1455 | if (Ty->isRecordType()) |
| 1456 | if (const CXXConstructExpr *E = |
| 1457 | dyn_cast_or_null<CXXConstructExpr>(D.getInit())) { |
| 1458 | const CXXConstructorDecl *CD = E->getConstructor(); |
| 1459 | if (CD->isTrivial() && CD->isDefaultConstructor()) |
| 1460 | return CGM.EmitNullConstant(D.getType()); |
| 1461 | } |
| 1462 | InConstantContext = true; |
| 1463 | } |
| 1464 | |
| 1465 | QualType destType = D.getType(); |
| 1466 | |
| 1467 | // Try to emit the initializer. Note that this can allow some things that |
| 1468 | // are not allowed by tryEmitPrivateForMemory alone. |
| 1469 | if (auto value = D.evaluateValue()) { |
| 1470 | return tryEmitPrivateForMemory(*value, destType); |
| 1471 | } |
| 1472 | |
| 1473 | // FIXME: Implement C++11 [basic.start.init]p2: if the initializer of a |
| 1474 | // reference is a constant expression, and the reference binds to a temporary, |
| 1475 | // then constant initialization is performed. ConstExprEmitter will |
| 1476 | // incorrectly emit a prvalue constant in this case, and the calling code |
| 1477 | // interprets that as the (pointer) value of the reference, rather than the |
| 1478 | // desired value of the referee. |
| 1479 | if (destType->isReferenceType()) |
| 1480 | return nullptr; |
| 1481 | |
| 1482 | const Expr *E = D.getInit(); |
| 1483 | assert(E && "No initializer to emit")((E && "No initializer to emit") ? static_cast<void > (0) : __assert_fail ("E && \"No initializer to emit\"" , "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 1483, __PRETTY_FUNCTION__)); |
| 1484 | |
| 1485 | auto nonMemoryDestType = getNonMemoryType(CGM, destType); |
| 1486 | auto C = |
| 1487 | ConstExprEmitter(*this).Visit(const_cast<Expr*>(E), nonMemoryDestType); |
| 1488 | return (C ? emitForMemory(C, destType) : nullptr); |
| 1489 | } |
| 1490 | |
| 1491 | llvm::Constant * |
| 1492 | ConstantEmitter::tryEmitAbstractForMemory(const Expr *E, QualType destType) { |
| 1493 | auto nonMemoryDestType = getNonMemoryType(CGM, destType); |
| 1494 | auto C = tryEmitAbstract(E, nonMemoryDestType); |
| 1495 | return (C ? emitForMemory(C, destType) : nullptr); |
| 1496 | } |
| 1497 | |
| 1498 | llvm::Constant * |
| 1499 | ConstantEmitter::tryEmitAbstractForMemory(const APValue &value, |
| 1500 | QualType destType) { |
| 1501 | auto nonMemoryDestType = getNonMemoryType(CGM, destType); |
| 1502 | auto C = tryEmitAbstract(value, nonMemoryDestType); |
| 1503 | return (C ? emitForMemory(C, destType) : nullptr); |
| 1504 | } |
| 1505 | |
| 1506 | llvm::Constant *ConstantEmitter::tryEmitPrivateForMemory(const Expr *E, |
| 1507 | QualType destType) { |
| 1508 | auto nonMemoryDestType = getNonMemoryType(CGM, destType); |
| 1509 | llvm::Constant *C = tryEmitPrivate(E, nonMemoryDestType); |
| 1510 | return (C ? emitForMemory(C, destType) : nullptr); |
| 1511 | } |
| 1512 | |
| 1513 | llvm::Constant *ConstantEmitter::tryEmitPrivateForMemory(const APValue &value, |
| 1514 | QualType destType) { |
| 1515 | auto nonMemoryDestType = getNonMemoryType(CGM, destType); |
| 1516 | auto C = tryEmitPrivate(value, nonMemoryDestType); |
| 1517 | return (C ? emitForMemory(C, destType) : nullptr); |
| 1518 | } |
| 1519 | |
| 1520 | llvm::Constant *ConstantEmitter::emitForMemory(CodeGenModule &CGM, |
| 1521 | llvm::Constant *C, |
| 1522 | QualType destType) { |
| 1523 | // For an _Atomic-qualified constant, we may need to add tail padding. |
| 1524 | if (auto AT = destType->getAs<AtomicType>()) { |
| 1525 | QualType destValueType = AT->getValueType(); |
| 1526 | C = emitForMemory(CGM, C, destValueType); |
| 1527 | |
| 1528 | uint64_t innerSize = CGM.getContext().getTypeSize(destValueType); |
| 1529 | uint64_t outerSize = CGM.getContext().getTypeSize(destType); |
| 1530 | if (innerSize == outerSize) |
| 1531 | return C; |
| 1532 | |
| 1533 | assert(innerSize < outerSize && "emitted over-large constant for atomic")((innerSize < outerSize && "emitted over-large constant for atomic" ) ? static_cast<void> (0) : __assert_fail ("innerSize < outerSize && \"emitted over-large constant for atomic\"" , "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 1533, __PRETTY_FUNCTION__)); |
| 1534 | llvm::Constant *elts[] = { |
| 1535 | C, |
| 1536 | llvm::ConstantAggregateZero::get( |
| 1537 | llvm::ArrayType::get(CGM.Int8Ty, (outerSize - innerSize) / 8)) |
| 1538 | }; |
| 1539 | return llvm::ConstantStruct::getAnon(elts); |
| 1540 | } |
| 1541 | |
| 1542 | // Zero-extend bool. |
| 1543 | if (C->getType()->isIntegerTy(1)) { |
| 1544 | llvm::Type *boolTy = CGM.getTypes().ConvertTypeForMem(destType); |
| 1545 | return llvm::ConstantExpr::getZExt(C, boolTy); |
| 1546 | } |
| 1547 | |
| 1548 | return C; |
| 1549 | } |
| 1550 | |
| 1551 | llvm::Constant *ConstantEmitter::tryEmitPrivate(const Expr *E, |
| 1552 | QualType destType) { |
| 1553 | Expr::EvalResult Result; |
| 1554 | |
| 1555 | bool Success = false; |
| 1556 | |
| 1557 | if (destType->isReferenceType()) |
| 1558 | Success = E->EvaluateAsLValue(Result, CGM.getContext()); |
| 1559 | else |
| 1560 | Success = E->EvaluateAsRValue(Result, CGM.getContext(), InConstantContext); |
| 1561 | |
| 1562 | llvm::Constant *C; |
| 1563 | if (Success && !Result.HasSideEffects) |
| 1564 | C = tryEmitPrivate(Result.Val, destType); |
| 1565 | else |
| 1566 | C = ConstExprEmitter(*this).Visit(const_cast<Expr*>(E), destType); |
| 1567 | |
| 1568 | return C; |
| 1569 | } |
| 1570 | |
| 1571 | llvm::Constant *CodeGenModule::getNullPointer(llvm::PointerType *T, QualType QT) { |
| 1572 | return getTargetCodeGenInfo().getNullPointer(*this, T, QT); |
| 1573 | } |
| 1574 | |
| 1575 | namespace { |
| 1576 | /// A struct which can be used to peephole certain kinds of finalization |
| 1577 | /// that normally happen during l-value emission. |
| 1578 | struct ConstantLValue { |
| 1579 | llvm::Constant *Value; |
| 1580 | bool HasOffsetApplied; |
| 1581 | |
| 1582 | /*implicit*/ ConstantLValue(llvm::Constant *value, |
| 1583 | bool hasOffsetApplied = false) |
| 1584 | : Value(value), HasOffsetApplied(false) {} |
| 1585 | |
| 1586 | /*implicit*/ ConstantLValue(ConstantAddress address) |
| 1587 | : ConstantLValue(address.getPointer()) {} |
| 1588 | }; |
| 1589 | |
| 1590 | /// A helper class for emitting constant l-values. |
| 1591 | class ConstantLValueEmitter : public ConstStmtVisitor<ConstantLValueEmitter, |
| 1592 | ConstantLValue> { |
| 1593 | CodeGenModule &CGM; |
| 1594 | ConstantEmitter &Emitter; |
| 1595 | const APValue &Value; |
| 1596 | QualType DestType; |
| 1597 | |
| 1598 | // Befriend StmtVisitorBase so that we don't have to expose Visit*. |
| 1599 | friend StmtVisitorBase; |
| 1600 | |
| 1601 | public: |
| 1602 | ConstantLValueEmitter(ConstantEmitter &emitter, const APValue &value, |
| 1603 | QualType destType) |
| 1604 | : CGM(emitter.CGM), Emitter(emitter), Value(value), DestType(destType) {} |
| 1605 | |
| 1606 | llvm::Constant *tryEmit(); |
| 1607 | |
| 1608 | private: |
| 1609 | llvm::Constant *tryEmitAbsolute(llvm::Type *destTy); |
| 1610 | ConstantLValue tryEmitBase(const APValue::LValueBase &base); |
| 1611 | |
| 1612 | ConstantLValue VisitStmt(const Stmt *S) { return nullptr; } |
| 1613 | ConstantLValue VisitConstantExpr(const ConstantExpr *E); |
| 1614 | ConstantLValue VisitCompoundLiteralExpr(const CompoundLiteralExpr *E); |
| 1615 | ConstantLValue VisitStringLiteral(const StringLiteral *E); |
| 1616 | ConstantLValue VisitObjCBoxedExpr(const ObjCBoxedExpr *E); |
| 1617 | ConstantLValue VisitObjCEncodeExpr(const ObjCEncodeExpr *E); |
| 1618 | ConstantLValue VisitObjCStringLiteral(const ObjCStringLiteral *E); |
| 1619 | ConstantLValue VisitPredefinedExpr(const PredefinedExpr *E); |
| 1620 | ConstantLValue VisitAddrLabelExpr(const AddrLabelExpr *E); |
| 1621 | ConstantLValue VisitCallExpr(const CallExpr *E); |
| 1622 | ConstantLValue VisitBlockExpr(const BlockExpr *E); |
| 1623 | ConstantLValue VisitCXXTypeidExpr(const CXXTypeidExpr *E); |
| 1624 | ConstantLValue VisitCXXUuidofExpr(const CXXUuidofExpr *E); |
| 1625 | ConstantLValue VisitMaterializeTemporaryExpr( |
| 1626 | const MaterializeTemporaryExpr *E); |
| 1627 | |
| 1628 | bool hasNonZeroOffset() const { |
| 1629 | return !Value.getLValueOffset().isZero(); |
| 1630 | } |
| 1631 | |
| 1632 | /// Return the value offset. |
| 1633 | llvm::Constant *getOffset() { |
| 1634 | return llvm::ConstantInt::get(CGM.Int64Ty, |
| 1635 | Value.getLValueOffset().getQuantity()); |
| 1636 | } |
| 1637 | |
| 1638 | /// Apply the value offset to the given constant. |
| 1639 | llvm::Constant *applyOffset(llvm::Constant *C) { |
| 1640 | if (!hasNonZeroOffset()) |
| 1641 | return C; |
| 1642 | |
| 1643 | llvm::Type *origPtrTy = C->getType(); |
| 1644 | unsigned AS = origPtrTy->getPointerAddressSpace(); |
| 1645 | llvm::Type *charPtrTy = CGM.Int8Ty->getPointerTo(AS); |
| 1646 | C = llvm::ConstantExpr::getBitCast(C, charPtrTy); |
| 1647 | C = llvm::ConstantExpr::getGetElementPtr(CGM.Int8Ty, C, getOffset()); |
| 1648 | C = llvm::ConstantExpr::getPointerCast(C, origPtrTy); |
| 1649 | return C; |
| 1650 | } |
| 1651 | }; |
| 1652 | |
| 1653 | } |
| 1654 | |
| 1655 | llvm::Constant *ConstantLValueEmitter::tryEmit() { |
| 1656 | const APValue::LValueBase &base = Value.getLValueBase(); |
| 1657 | |
| 1658 | // The destination type should be a pointer or reference |
| 1659 | // type, but it might also be a cast thereof. |
| 1660 | // |
| 1661 | // FIXME: the chain of casts required should be reflected in the APValue. |
| 1662 | // We need this in order to correctly handle things like a ptrtoint of a |
| 1663 | // non-zero null pointer and addrspace casts that aren't trivially |
| 1664 | // represented in LLVM IR. |
| 1665 | auto destTy = CGM.getTypes().ConvertTypeForMem(DestType); |
| 1666 | assert(isa<llvm::IntegerType>(destTy) || isa<llvm::PointerType>(destTy))((isa<llvm::IntegerType>(destTy) || isa<llvm::PointerType >(destTy)) ? static_cast<void> (0) : __assert_fail ( "isa<llvm::IntegerType>(destTy) || isa<llvm::PointerType>(destTy)" , "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 1666, __PRETTY_FUNCTION__)); |
| 1667 | |
| 1668 | // If there's no base at all, this is a null or absolute pointer, |
| 1669 | // possibly cast back to an integer type. |
| 1670 | if (!base) { |
| 1671 | return tryEmitAbsolute(destTy); |
| 1672 | } |
| 1673 | |
| 1674 | // Otherwise, try to emit the base. |
| 1675 | ConstantLValue result = tryEmitBase(base); |
| 1676 | |
| 1677 | // If that failed, we're done. |
| 1678 | llvm::Constant *value = result.Value; |
| 1679 | if (!value) return nullptr; |
| 1680 | |
| 1681 | // Apply the offset if necessary and not already done. |
| 1682 | if (!result.HasOffsetApplied) { |
| 1683 | value = applyOffset(value); |
| 1684 | } |
| 1685 | |
| 1686 | // Convert to the appropriate type; this could be an lvalue for |
| 1687 | // an integer. FIXME: performAddrSpaceCast |
| 1688 | if (isa<llvm::PointerType>(destTy)) |
| 1689 | return llvm::ConstantExpr::getPointerCast(value, destTy); |
| 1690 | |
| 1691 | return llvm::ConstantExpr::getPtrToInt(value, destTy); |
| 1692 | } |
| 1693 | |
| 1694 | /// Try to emit an absolute l-value, such as a null pointer or an integer |
| 1695 | /// bitcast to pointer type. |
| 1696 | llvm::Constant * |
| 1697 | ConstantLValueEmitter::tryEmitAbsolute(llvm::Type *destTy) { |
| 1698 | auto offset = getOffset(); |
| 1699 | |
| 1700 | // If we're producing a pointer, this is easy. |
| 1701 | auto destPtrTy = cast<llvm::PointerType>(destTy); |
| 1702 | if (Value.isNullPointer()) { |
| 1703 | // FIXME: integer offsets from non-zero null pointers. |
| 1704 | return CGM.getNullPointer(destPtrTy, DestType); |
| 1705 | } |
| 1706 | |
| 1707 | // Convert the integer to a pointer-sized integer before converting it |
| 1708 | // to a pointer. |
| 1709 | // FIXME: signedness depends on the original integer type. |
| 1710 | auto intptrTy = CGM.getDataLayout().getIntPtrType(destPtrTy); |
| 1711 | llvm::Constant *C = offset; |
Value stored to 'C' during its initialization is never read | |
| 1712 | C = llvm::ConstantExpr::getIntegerCast(getOffset(), intptrTy, |
| 1713 | /*isSigned*/ false); |
| 1714 | C = llvm::ConstantExpr::getIntToPtr(C, destPtrTy); |
| 1715 | return C; |
| 1716 | } |
| 1717 | |
| 1718 | ConstantLValue |
| 1719 | ConstantLValueEmitter::tryEmitBase(const APValue::LValueBase &base) { |
| 1720 | // Handle values. |
| 1721 | if (const ValueDecl *D = base.dyn_cast<const ValueDecl*>()) { |
| 1722 | if (D->hasAttr<WeakRefAttr>()) |
| 1723 | return CGM.GetWeakRefReference(D).getPointer(); |
| 1724 | |
| 1725 | if (auto FD = dyn_cast<FunctionDecl>(D)) |
| 1726 | return CGM.GetAddrOfFunction(FD); |
| 1727 | |
| 1728 | if (auto VD = dyn_cast<VarDecl>(D)) { |
| 1729 | // We can never refer to a variable with local storage. |
| 1730 | if (!VD->hasLocalStorage()) { |
| 1731 | if (VD->isFileVarDecl() || VD->hasExternalStorage()) |
| 1732 | return CGM.GetAddrOfGlobalVar(VD); |
| 1733 | |
| 1734 | if (VD->isLocalVarDecl()) { |
| 1735 | return CGM.getOrCreateStaticVarDecl( |
| 1736 | *VD, CGM.getLLVMLinkageVarDefinition(VD, /*isConstant=*/false)); |
| 1737 | } |
| 1738 | } |
| 1739 | } |
| 1740 | |
| 1741 | return nullptr; |
| 1742 | } |
| 1743 | |
| 1744 | // Otherwise, it must be an expression. |
| 1745 | return Visit(base.get<const Expr*>()); |
| 1746 | } |
| 1747 | |
| 1748 | ConstantLValue |
| 1749 | ConstantLValueEmitter::VisitConstantExpr(const ConstantExpr *E) { |
| 1750 | return Visit(E->getSubExpr()); |
| 1751 | } |
| 1752 | |
| 1753 | ConstantLValue |
| 1754 | ConstantLValueEmitter::VisitCompoundLiteralExpr(const CompoundLiteralExpr *E) { |
| 1755 | return tryEmitGlobalCompoundLiteral(CGM, Emitter.CGF, E); |
| 1756 | } |
| 1757 | |
| 1758 | ConstantLValue |
| 1759 | ConstantLValueEmitter::VisitStringLiteral(const StringLiteral *E) { |
| 1760 | return CGM.GetAddrOfConstantStringFromLiteral(E); |
| 1761 | } |
| 1762 | |
| 1763 | ConstantLValue |
| 1764 | ConstantLValueEmitter::VisitObjCEncodeExpr(const ObjCEncodeExpr *E) { |
| 1765 | return CGM.GetAddrOfConstantStringFromObjCEncode(E); |
| 1766 | } |
| 1767 | |
| 1768 | static ConstantLValue emitConstantObjCStringLiteral(const StringLiteral *S, |
| 1769 | QualType T, |
| 1770 | CodeGenModule &CGM) { |
| 1771 | auto C = CGM.getObjCRuntime().GenerateConstantString(S); |
| 1772 | return C.getElementBitCast(CGM.getTypes().ConvertTypeForMem(T)); |
| 1773 | } |
| 1774 | |
| 1775 | ConstantLValue |
| 1776 | ConstantLValueEmitter::VisitObjCStringLiteral(const ObjCStringLiteral *E) { |
| 1777 | return emitConstantObjCStringLiteral(E->getString(), E->getType(), CGM); |
| 1778 | } |
| 1779 | |
| 1780 | ConstantLValue |
| 1781 | ConstantLValueEmitter::VisitObjCBoxedExpr(const ObjCBoxedExpr *E) { |
| 1782 | assert(E->isExpressibleAsConstantInitializer() &&((E->isExpressibleAsConstantInitializer() && "this boxed expression can't be emitted as a compile-time constant" ) ? static_cast<void> (0) : __assert_fail ("E->isExpressibleAsConstantInitializer() && \"this boxed expression can't be emitted as a compile-time constant\"" , "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 1783, __PRETTY_FUNCTION__)) |
| 1783 | "this boxed expression can't be emitted as a compile-time constant")((E->isExpressibleAsConstantInitializer() && "this boxed expression can't be emitted as a compile-time constant" ) ? static_cast<void> (0) : __assert_fail ("E->isExpressibleAsConstantInitializer() && \"this boxed expression can't be emitted as a compile-time constant\"" , "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 1783, __PRETTY_FUNCTION__)); |
| 1784 | auto *SL = cast<StringLiteral>(E->getSubExpr()->IgnoreParenCasts()); |
| 1785 | return emitConstantObjCStringLiteral(SL, E->getType(), CGM); |
| 1786 | } |
| 1787 | |
| 1788 | ConstantLValue |
| 1789 | ConstantLValueEmitter::VisitPredefinedExpr(const PredefinedExpr *E) { |
| 1790 | return CGM.GetAddrOfConstantStringFromLiteral(E->getFunctionName()); |
| 1791 | } |
| 1792 | |
| 1793 | ConstantLValue |
| 1794 | ConstantLValueEmitter::VisitAddrLabelExpr(const AddrLabelExpr *E) { |
| 1795 | assert(Emitter.CGF && "Invalid address of label expression outside function")((Emitter.CGF && "Invalid address of label expression outside function" ) ? static_cast<void> (0) : __assert_fail ("Emitter.CGF && \"Invalid address of label expression outside function\"" , "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 1795, __PRETTY_FUNCTION__)); |
| 1796 | llvm::Constant *Ptr = Emitter.CGF->GetAddrOfLabel(E->getLabel()); |
| 1797 | Ptr = llvm::ConstantExpr::getBitCast(Ptr, |
| 1798 | CGM.getTypes().ConvertType(E->getType())); |
| 1799 | return Ptr; |
| 1800 | } |
| 1801 | |
| 1802 | ConstantLValue |
| 1803 | ConstantLValueEmitter::VisitCallExpr(const CallExpr *E) { |
| 1804 | unsigned builtin = E->getBuiltinCallee(); |
| 1805 | if (builtin != Builtin::BI__builtin___CFStringMakeConstantString && |
| 1806 | builtin != Builtin::BI__builtin___NSStringMakeConstantString) |
| 1807 | return nullptr; |
| 1808 | |
| 1809 | auto literal = cast<StringLiteral>(E->getArg(0)->IgnoreParenCasts()); |
| 1810 | if (builtin == Builtin::BI__builtin___NSStringMakeConstantString) { |
| 1811 | return CGM.getObjCRuntime().GenerateConstantString(literal); |
| 1812 | } else { |
| 1813 | // FIXME: need to deal with UCN conversion issues. |
| 1814 | return CGM.GetAddrOfConstantCFString(literal); |
| 1815 | } |
| 1816 | } |
| 1817 | |
| 1818 | ConstantLValue |
| 1819 | ConstantLValueEmitter::VisitBlockExpr(const BlockExpr *E) { |
| 1820 | StringRef functionName; |
| 1821 | if (auto CGF = Emitter.CGF) |
| 1822 | functionName = CGF->CurFn->getName(); |
| 1823 | else |
| 1824 | functionName = "global"; |
| 1825 | |
| 1826 | return CGM.GetAddrOfGlobalBlock(E, functionName); |
| 1827 | } |
| 1828 | |
| 1829 | ConstantLValue |
| 1830 | ConstantLValueEmitter::VisitCXXTypeidExpr(const CXXTypeidExpr *E) { |
| 1831 | QualType T; |
| 1832 | if (E->isTypeOperand()) |
| 1833 | T = E->getTypeOperand(CGM.getContext()); |
| 1834 | else |
| 1835 | T = E->getExprOperand()->getType(); |
| 1836 | return CGM.GetAddrOfRTTIDescriptor(T); |
| 1837 | } |
| 1838 | |
| 1839 | ConstantLValue |
| 1840 | ConstantLValueEmitter::VisitCXXUuidofExpr(const CXXUuidofExpr *E) { |
| 1841 | return CGM.GetAddrOfUuidDescriptor(E); |
| 1842 | } |
| 1843 | |
| 1844 | ConstantLValue |
| 1845 | ConstantLValueEmitter::VisitMaterializeTemporaryExpr( |
| 1846 | const MaterializeTemporaryExpr *E) { |
| 1847 | assert(E->getStorageDuration() == SD_Static)((E->getStorageDuration() == SD_Static) ? static_cast<void > (0) : __assert_fail ("E->getStorageDuration() == SD_Static" , "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 1847, __PRETTY_FUNCTION__)); |
| 1848 | SmallVector<const Expr *, 2> CommaLHSs; |
| 1849 | SmallVector<SubobjectAdjustment, 2> Adjustments; |
| 1850 | const Expr *Inner = E->GetTemporaryExpr() |
| 1851 | ->skipRValueSubobjectAdjustments(CommaLHSs, Adjustments); |
| 1852 | return CGM.GetAddrOfGlobalTemporary(E, Inner); |
| 1853 | } |
| 1854 | |
| 1855 | llvm::Constant *ConstantEmitter::tryEmitPrivate(const APValue &Value, |
| 1856 | QualType DestType) { |
| 1857 | switch (Value.getKind()) { |
| 1858 | case APValue::Uninitialized: |
| 1859 | llvm_unreachable("Constant expressions should be initialized.")::llvm::llvm_unreachable_internal("Constant expressions should be initialized." , "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 1859); |
| 1860 | case APValue::LValue: |
| 1861 | return ConstantLValueEmitter(*this, Value, DestType).tryEmit(); |
| 1862 | case APValue::Int: |
| 1863 | return llvm::ConstantInt::get(CGM.getLLVMContext(), Value.getInt()); |
| 1864 | case APValue::FixedPoint: |
| 1865 | return llvm::ConstantInt::get(CGM.getLLVMContext(), |
| 1866 | Value.getFixedPoint().getValue()); |
| 1867 | case APValue::ComplexInt: { |
| 1868 | llvm::Constant *Complex[2]; |
| 1869 | |
| 1870 | Complex[0] = llvm::ConstantInt::get(CGM.getLLVMContext(), |
| 1871 | Value.getComplexIntReal()); |
| 1872 | Complex[1] = llvm::ConstantInt::get(CGM.getLLVMContext(), |
| 1873 | Value.getComplexIntImag()); |
| 1874 | |
| 1875 | // FIXME: the target may want to specify that this is packed. |
| 1876 | llvm::StructType *STy = |
| 1877 | llvm::StructType::get(Complex[0]->getType(), Complex[1]->getType()); |
| 1878 | return llvm::ConstantStruct::get(STy, Complex); |
| 1879 | } |
| 1880 | case APValue::Float: { |
| 1881 | const llvm::APFloat &Init = Value.getFloat(); |
| 1882 | if (&Init.getSemantics() == &llvm::APFloat::IEEEhalf() && |
| 1883 | !CGM.getContext().getLangOpts().NativeHalfType && |
| 1884 | CGM.getContext().getTargetInfo().useFP16ConversionIntrinsics()) |
| 1885 | return llvm::ConstantInt::get(CGM.getLLVMContext(), |
| 1886 | Init.bitcastToAPInt()); |
| 1887 | else |
| 1888 | return llvm::ConstantFP::get(CGM.getLLVMContext(), Init); |
| 1889 | } |
| 1890 | case APValue::ComplexFloat: { |
| 1891 | llvm::Constant *Complex[2]; |
| 1892 | |
| 1893 | Complex[0] = llvm::ConstantFP::get(CGM.getLLVMContext(), |
| 1894 | Value.getComplexFloatReal()); |
| 1895 | Complex[1] = llvm::ConstantFP::get(CGM.getLLVMContext(), |
| 1896 | Value.getComplexFloatImag()); |
| 1897 | |
| 1898 | // FIXME: the target may want to specify that this is packed. |
| 1899 | llvm::StructType *STy = |
| 1900 | llvm::StructType::get(Complex[0]->getType(), Complex[1]->getType()); |
| 1901 | return llvm::ConstantStruct::get(STy, Complex); |
| 1902 | } |
| 1903 | case APValue::Vector: { |
| 1904 | unsigned NumElts = Value.getVectorLength(); |
| 1905 | SmallVector<llvm::Constant *, 4> Inits(NumElts); |
| 1906 | |
| 1907 | for (unsigned I = 0; I != NumElts; ++I) { |
| 1908 | const APValue &Elt = Value.getVectorElt(I); |
| 1909 | if (Elt.isInt()) |
| 1910 | Inits[I] = llvm::ConstantInt::get(CGM.getLLVMContext(), Elt.getInt()); |
| 1911 | else if (Elt.isFloat()) |
| 1912 | Inits[I] = llvm::ConstantFP::get(CGM.getLLVMContext(), Elt.getFloat()); |
| 1913 | else |
| 1914 | llvm_unreachable("unsupported vector element type")::llvm::llvm_unreachable_internal("unsupported vector element type" , "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 1914); |
| 1915 | } |
| 1916 | return llvm::ConstantVector::get(Inits); |
| 1917 | } |
| 1918 | case APValue::AddrLabelDiff: { |
| 1919 | const AddrLabelExpr *LHSExpr = Value.getAddrLabelDiffLHS(); |
| 1920 | const AddrLabelExpr *RHSExpr = Value.getAddrLabelDiffRHS(); |
| 1921 | llvm::Constant *LHS = tryEmitPrivate(LHSExpr, LHSExpr->getType()); |
| 1922 | llvm::Constant *RHS = tryEmitPrivate(RHSExpr, RHSExpr->getType()); |
| 1923 | if (!LHS || !RHS) return nullptr; |
| 1924 | |
| 1925 | // Compute difference |
| 1926 | llvm::Type *ResultType = CGM.getTypes().ConvertType(DestType); |
| 1927 | LHS = llvm::ConstantExpr::getPtrToInt(LHS, CGM.IntPtrTy); |
| 1928 | RHS = llvm::ConstantExpr::getPtrToInt(RHS, CGM.IntPtrTy); |
| 1929 | llvm::Constant *AddrLabelDiff = llvm::ConstantExpr::getSub(LHS, RHS); |
| 1930 | |
| 1931 | // LLVM is a bit sensitive about the exact format of the |
| 1932 | // address-of-label difference; make sure to truncate after |
| 1933 | // the subtraction. |
| 1934 | return llvm::ConstantExpr::getTruncOrBitCast(AddrLabelDiff, ResultType); |
| 1935 | } |
| 1936 | case APValue::Struct: |
| 1937 | case APValue::Union: |
| 1938 | return ConstStructBuilder::BuildStruct(*this, Value, DestType); |
| 1939 | case APValue::Array: { |
| 1940 | const ConstantArrayType *CAT = |
| 1941 | CGM.getContext().getAsConstantArrayType(DestType); |
| 1942 | unsigned NumElements = Value.getArraySize(); |
| 1943 | unsigned NumInitElts = Value.getArrayInitializedElts(); |
| 1944 | |
| 1945 | // Emit array filler, if there is one. |
| 1946 | llvm::Constant *Filler = nullptr; |
| 1947 | if (Value.hasArrayFiller()) { |
| 1948 | Filler = tryEmitAbstractForMemory(Value.getArrayFiller(), |
| 1949 | CAT->getElementType()); |
| 1950 | if (!Filler) |
| 1951 | return nullptr; |
| 1952 | } |
| 1953 | |
| 1954 | // Emit initializer elements. |
| 1955 | SmallVector<llvm::Constant*, 16> Elts; |
| 1956 | if (Filler && Filler->isNullValue()) |
| 1957 | Elts.reserve(NumInitElts + 1); |
| 1958 | else |
| 1959 | Elts.reserve(NumElements); |
| 1960 | |
| 1961 | llvm::Type *CommonElementType = nullptr; |
| 1962 | for (unsigned I = 0; I < NumInitElts; ++I) { |
| 1963 | llvm::Constant *C = tryEmitPrivateForMemory( |
| 1964 | Value.getArrayInitializedElt(I), CAT->getElementType()); |
| 1965 | if (!C) return nullptr; |
| 1966 | |
| 1967 | if (I == 0) |
| 1968 | CommonElementType = C->getType(); |
| 1969 | else if (C->getType() != CommonElementType) |
| 1970 | CommonElementType = nullptr; |
| 1971 | Elts.push_back(C); |
| 1972 | } |
| 1973 | |
| 1974 | // This means that the array type is probably "IncompleteType" or some |
| 1975 | // type that is not ConstantArray. |
| 1976 | if (CAT == nullptr && CommonElementType == nullptr && !NumInitElts) { |
| 1977 | const ArrayType *AT = CGM.getContext().getAsArrayType(DestType); |
| 1978 | CommonElementType = CGM.getTypes().ConvertType(AT->getElementType()); |
| 1979 | llvm::ArrayType *AType = llvm::ArrayType::get(CommonElementType, |
| 1980 | NumElements); |
| 1981 | return llvm::ConstantAggregateZero::get(AType); |
| 1982 | } |
| 1983 | |
| 1984 | return EmitArrayConstant(CGM, CAT, CommonElementType, NumElements, Elts, |
| 1985 | Filler); |
| 1986 | } |
| 1987 | case APValue::MemberPointer: |
| 1988 | return CGM.getCXXABI().EmitMemberPointer(Value, DestType); |
| 1989 | } |
| 1990 | llvm_unreachable("Unknown APValue kind")::llvm::llvm_unreachable_internal("Unknown APValue kind", "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 1990); |
| 1991 | } |
| 1992 | |
| 1993 | llvm::GlobalVariable *CodeGenModule::getAddrOfConstantCompoundLiteralIfEmitted( |
| 1994 | const CompoundLiteralExpr *E) { |
| 1995 | return EmittedCompoundLiterals.lookup(E); |
| 1996 | } |
| 1997 | |
| 1998 | void CodeGenModule::setAddrOfConstantCompoundLiteral( |
| 1999 | const CompoundLiteralExpr *CLE, llvm::GlobalVariable *GV) { |
| 2000 | bool Ok = EmittedCompoundLiterals.insert(std::make_pair(CLE, GV)).second; |
| 2001 | (void)Ok; |
| 2002 | assert(Ok && "CLE has already been emitted!")((Ok && "CLE has already been emitted!") ? static_cast <void> (0) : __assert_fail ("Ok && \"CLE has already been emitted!\"" , "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 2002, __PRETTY_FUNCTION__)); |
| 2003 | } |
| 2004 | |
| 2005 | ConstantAddress |
| 2006 | CodeGenModule::GetAddrOfConstantCompoundLiteral(const CompoundLiteralExpr *E) { |
| 2007 | assert(E->isFileScope() && "not a file-scope compound literal expr")((E->isFileScope() && "not a file-scope compound literal expr" ) ? static_cast<void> (0) : __assert_fail ("E->isFileScope() && \"not a file-scope compound literal expr\"" , "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 2007, __PRETTY_FUNCTION__)); |
| 2008 | return tryEmitGlobalCompoundLiteral(*this, nullptr, E); |
| 2009 | } |
| 2010 | |
| 2011 | llvm::Constant * |
| 2012 | CodeGenModule::getMemberPointerConstant(const UnaryOperator *uo) { |
| 2013 | // Member pointer constants always have a very particular form. |
| 2014 | const MemberPointerType *type = cast<MemberPointerType>(uo->getType()); |
| 2015 | const ValueDecl *decl = cast<DeclRefExpr>(uo->getSubExpr())->getDecl(); |
| 2016 | |
| 2017 | // A member function pointer. |
| 2018 | if (const CXXMethodDecl *method = dyn_cast<CXXMethodDecl>(decl)) |
| 2019 | return getCXXABI().EmitMemberFunctionPointer(method); |
| 2020 | |
| 2021 | // Otherwise, a member data pointer. |
| 2022 | uint64_t fieldOffset = getContext().getFieldOffset(decl); |
| 2023 | CharUnits chars = getContext().toCharUnitsFromBits((int64_t) fieldOffset); |
| 2024 | return getCXXABI().EmitMemberDataPointer(type, chars); |
| 2025 | } |
| 2026 | |
| 2027 | static llvm::Constant *EmitNullConstantForBase(CodeGenModule &CGM, |
| 2028 | llvm::Type *baseType, |
| 2029 | const CXXRecordDecl *base); |
| 2030 | |
| 2031 | static llvm::Constant *EmitNullConstant(CodeGenModule &CGM, |
| 2032 | const RecordDecl *record, |
| 2033 | bool asCompleteObject) { |
| 2034 | const CGRecordLayout &layout = CGM.getTypes().getCGRecordLayout(record); |
| 2035 | llvm::StructType *structure = |
| 2036 | (asCompleteObject ? layout.getLLVMType() |
| 2037 | : layout.getBaseSubobjectLLVMType()); |
| 2038 | |
| 2039 | unsigned numElements = structure->getNumElements(); |
| 2040 | std::vector<llvm::Constant *> elements(numElements); |
| 2041 | |
| 2042 | auto CXXR = dyn_cast<CXXRecordDecl>(record); |
| 2043 | // Fill in all the bases. |
| 2044 | if (CXXR) { |
| 2045 | for (const auto &I : CXXR->bases()) { |
| 2046 | if (I.isVirtual()) { |
| 2047 | // Ignore virtual bases; if we're laying out for a complete |
| 2048 | // object, we'll lay these out later. |
| 2049 | continue; |
| 2050 | } |
| 2051 | |
| 2052 | const CXXRecordDecl *base = |
| 2053 | cast<CXXRecordDecl>(I.getType()->castAs<RecordType>()->getDecl()); |
| 2054 | |
| 2055 | // Ignore empty bases. |
| 2056 | if (base->isEmpty() || |
| 2057 | CGM.getContext().getASTRecordLayout(base).getNonVirtualSize() |
| 2058 | .isZero()) |
| 2059 | continue; |
| 2060 | |
| 2061 | unsigned fieldIndex = layout.getNonVirtualBaseLLVMFieldNo(base); |
| 2062 | llvm::Type *baseType = structure->getElementType(fieldIndex); |
| 2063 | elements[fieldIndex] = EmitNullConstantForBase(CGM, baseType, base); |
| 2064 | } |
| 2065 | } |
| 2066 | |
| 2067 | // Fill in all the fields. |
| 2068 | for (const auto *Field : record->fields()) { |
| 2069 | // Fill in non-bitfields. (Bitfields always use a zero pattern, which we |
| 2070 | // will fill in later.) |
| 2071 | if (!Field->isBitField()) { |
| 2072 | unsigned fieldIndex = layout.getLLVMFieldNo(Field); |
| 2073 | elements[fieldIndex] = CGM.EmitNullConstant(Field->getType()); |
| 2074 | } |
| 2075 | |
| 2076 | // For unions, stop after the first named field. |
| 2077 | if (record->isUnion()) { |
| 2078 | if (Field->getIdentifier()) |
| 2079 | break; |
| 2080 | if (const auto *FieldRD = Field->getType()->getAsRecordDecl()) |
| 2081 | if (FieldRD->findFirstNamedDataMember()) |
| 2082 | break; |
| 2083 | } |
| 2084 | } |
| 2085 | |
| 2086 | // Fill in the virtual bases, if we're working with the complete object. |
| 2087 | if (CXXR && asCompleteObject) { |
| 2088 | for (const auto &I : CXXR->vbases()) { |
| 2089 | const CXXRecordDecl *base = |
| 2090 | cast<CXXRecordDecl>(I.getType()->castAs<RecordType>()->getDecl()); |
| 2091 | |
| 2092 | // Ignore empty bases. |
| 2093 | if (base->isEmpty()) |
| 2094 | continue; |
| 2095 | |
| 2096 | unsigned fieldIndex = layout.getVirtualBaseIndex(base); |
| 2097 | |
| 2098 | // We might have already laid this field out. |
| 2099 | if (elements[fieldIndex]) continue; |
| 2100 | |
| 2101 | llvm::Type *baseType = structure->getElementType(fieldIndex); |
| 2102 | elements[fieldIndex] = EmitNullConstantForBase(CGM, baseType, base); |
| 2103 | } |
| 2104 | } |
| 2105 | |
| 2106 | // Now go through all other fields and zero them out. |
| 2107 | for (unsigned i = 0; i != numElements; ++i) { |
| 2108 | if (!elements[i]) |
| 2109 | elements[i] = llvm::Constant::getNullValue(structure->getElementType(i)); |
| 2110 | } |
| 2111 | |
| 2112 | return llvm::ConstantStruct::get(structure, elements); |
| 2113 | } |
| 2114 | |
| 2115 | /// Emit the null constant for a base subobject. |
| 2116 | static llvm::Constant *EmitNullConstantForBase(CodeGenModule &CGM, |
| 2117 | llvm::Type *baseType, |
| 2118 | const CXXRecordDecl *base) { |
| 2119 | const CGRecordLayout &baseLayout = CGM.getTypes().getCGRecordLayout(base); |
| 2120 | |
| 2121 | // Just zero out bases that don't have any pointer to data members. |
| 2122 | if (baseLayout.isZeroInitializableAsBase()) |
| 2123 | return llvm::Constant::getNullValue(baseType); |
| 2124 | |
| 2125 | // Otherwise, we can just use its null constant. |
| 2126 | return EmitNullConstant(CGM, base, /*asCompleteObject=*/false); |
| 2127 | } |
| 2128 | |
| 2129 | llvm::Constant *ConstantEmitter::emitNullForMemory(CodeGenModule &CGM, |
| 2130 | QualType T) { |
| 2131 | return emitForMemory(CGM, CGM.EmitNullConstant(T), T); |
| 2132 | } |
| 2133 | |
| 2134 | llvm::Constant *CodeGenModule::EmitNullConstant(QualType T) { |
| 2135 | if (T->getAs<PointerType>()) |
| 2136 | return getNullPointer( |
| 2137 | cast<llvm::PointerType>(getTypes().ConvertTypeForMem(T)), T); |
| 2138 | |
| 2139 | if (getTypes().isZeroInitializable(T)) |
| 2140 | return llvm::Constant::getNullValue(getTypes().ConvertTypeForMem(T)); |
| 2141 | |
| 2142 | if (const ConstantArrayType *CAT = Context.getAsConstantArrayType(T)) { |
| 2143 | llvm::ArrayType *ATy = |
| 2144 | cast<llvm::ArrayType>(getTypes().ConvertTypeForMem(T)); |
| 2145 | |
| 2146 | QualType ElementTy = CAT->getElementType(); |
| 2147 | |
| 2148 | llvm::Constant *Element = |
| 2149 | ConstantEmitter::emitNullForMemory(*this, ElementTy); |
| 2150 | unsigned NumElements = CAT->getSize().getZExtValue(); |
| 2151 | SmallVector<llvm::Constant *, 8> Array(NumElements, Element); |
| 2152 | return llvm::ConstantArray::get(ATy, Array); |
| 2153 | } |
| 2154 | |
| 2155 | if (const RecordType *RT = T->getAs<RecordType>()) |
| 2156 | return ::EmitNullConstant(*this, RT->getDecl(), /*complete object*/ true); |
| 2157 | |
| 2158 | assert(T->isMemberDataPointerType() &&((T->isMemberDataPointerType() && "Should only see pointers to data members here!" ) ? static_cast<void> (0) : __assert_fail ("T->isMemberDataPointerType() && \"Should only see pointers to data members here!\"" , "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 2159, __PRETTY_FUNCTION__)) |
| 2159 | "Should only see pointers to data members here!")((T->isMemberDataPointerType() && "Should only see pointers to data members here!" ) ? static_cast<void> (0) : __assert_fail ("T->isMemberDataPointerType() && \"Should only see pointers to data members here!\"" , "/build/llvm-toolchain-snapshot-9~svn360410/tools/clang/lib/CodeGen/CGExprConstant.cpp" , 2159, __PRETTY_FUNCTION__)); |
| 2160 | |
| 2161 | return getCXXABI().EmitNullMemberPointer(T->castAs<MemberPointerType>()); |
| 2162 | } |
| 2163 | |
| 2164 | llvm::Constant * |
| 2165 | CodeGenModule::EmitNullConstantForBase(const CXXRecordDecl *Record) { |
| 2166 | return ::EmitNullConstant(*this, Record, false); |
| 2167 | } |