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 | } |