1 | //===-- CGValue.h - LLVM CodeGen wrappers for llvm::Value* ------*- C++ -*-===// |
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 | // These classes implement wrappers around llvm::Value in order to |
10 | // fully represent the range of values for C L- and R- values. |
11 | // |
12 | //===----------------------------------------------------------------------===// |
13 | |
14 | #ifndef LLVM_CLANG_LIB_CODEGEN_CGVALUE_H |
15 | #define LLVM_CLANG_LIB_CODEGEN_CGVALUE_H |
16 | |
17 | #include "Address.h" |
18 | #include "CGPointerAuthInfo.h" |
19 | #include "CodeGenTBAA.h" |
20 | #include "EHScopeStack.h" |
21 | #include "clang/AST/ASTContext.h" |
22 | #include "clang/AST/Type.h" |
23 | #include "llvm/IR/Type.h" |
24 | #include "llvm/IR/Value.h" |
25 | |
26 | namespace llvm { |
27 | class Constant; |
28 | class MDNode; |
29 | } |
30 | |
31 | namespace clang { |
32 | namespace CodeGen { |
33 | class AggValueSlot; |
34 | class CGBuilderTy; |
35 | class CodeGenFunction; |
36 | struct CGBitFieldInfo; |
37 | |
38 | /// RValue - This trivial value class is used to represent the result of an |
39 | /// expression that is evaluated. It can be one of three things: either a |
40 | /// simple LLVM SSA value, a pair of SSA values for complex numbers, or the |
41 | /// address of an aggregate value in memory. |
42 | class RValue { |
43 | friend struct DominatingValue<RValue>; |
44 | |
45 | enum FlavorEnum { Scalar, Complex, Aggregate }; |
46 | |
47 | union { |
48 | // Stores first and second value. |
49 | struct { |
50 | llvm::Value *first; |
51 | llvm::Value *second; |
52 | } Vals; |
53 | |
54 | // Stores aggregate address. |
55 | Address AggregateAddr; |
56 | }; |
57 | |
58 | unsigned IsVolatile : 1; |
59 | unsigned Flavor : 2; |
60 | |
61 | public: |
62 | RValue() : Vals{.first: nullptr, .second: nullptr}, Flavor(Scalar) {} |
63 | |
64 | bool isScalar() const { return Flavor == Scalar; } |
65 | bool isComplex() const { return Flavor == Complex; } |
66 | bool isAggregate() const { return Flavor == Aggregate; } |
67 | |
68 | bool isVolatileQualified() const { return IsVolatile; } |
69 | |
70 | /// getScalarVal() - Return the Value* of this scalar value. |
71 | llvm::Value *getScalarVal() const { |
72 | assert(isScalar() && "Not a scalar!" ); |
73 | return Vals.first; |
74 | } |
75 | |
76 | /// getComplexVal - Return the real/imag components of this complex value. |
77 | /// |
78 | std::pair<llvm::Value *, llvm::Value *> getComplexVal() const { |
79 | return std::make_pair(x: Vals.first, y: Vals.second); |
80 | } |
81 | |
82 | /// getAggregateAddr() - Return the Value* of the address of the aggregate. |
83 | Address getAggregateAddress() const { |
84 | assert(isAggregate() && "Not an aggregate!" ); |
85 | return AggregateAddr; |
86 | } |
87 | |
88 | llvm::Value *getAggregatePointer(QualType PointeeType, |
89 | CodeGenFunction &CGF) const { |
90 | return getAggregateAddress().getBasePointer(); |
91 | } |
92 | |
93 | static RValue getIgnored() { |
94 | // FIXME: should we make this a more explicit state? |
95 | return get(V: nullptr); |
96 | } |
97 | |
98 | static RValue get(llvm::Value *V) { |
99 | RValue ER; |
100 | ER.Vals.first = V; |
101 | ER.Flavor = Scalar; |
102 | ER.IsVolatile = false; |
103 | return ER; |
104 | } |
105 | static RValue get(Address Addr, CodeGenFunction &CGF) { |
106 | return RValue::get(V: Addr.emitRawPointer(CGF)); |
107 | } |
108 | static RValue getComplex(llvm::Value *V1, llvm::Value *V2) { |
109 | RValue ER; |
110 | ER.Vals = {.first: V1, .second: V2}; |
111 | ER.Flavor = Complex; |
112 | ER.IsVolatile = false; |
113 | return ER; |
114 | } |
115 | static RValue getComplex(const std::pair<llvm::Value *, llvm::Value *> &C) { |
116 | return getComplex(V1: C.first, V2: C.second); |
117 | } |
118 | // FIXME: Aggregate rvalues need to retain information about whether they are |
119 | // volatile or not. Remove default to find all places that probably get this |
120 | // wrong. |
121 | |
122 | /// Convert an Address to an RValue. If the Address is not |
123 | /// signed, create an RValue using the unsigned address. Otherwise, resign the |
124 | /// address using the provided type. |
125 | static RValue getAggregate(Address addr, bool isVolatile = false) { |
126 | RValue ER; |
127 | ER.AggregateAddr = addr; |
128 | ER.Flavor = Aggregate; |
129 | ER.IsVolatile = isVolatile; |
130 | return ER; |
131 | } |
132 | }; |
133 | |
134 | /// Does an ARC strong l-value have precise lifetime? |
135 | enum ARCPreciseLifetime_t { |
136 | ARCImpreciseLifetime, ARCPreciseLifetime |
137 | }; |
138 | |
139 | /// The source of the alignment of an l-value; an expression of |
140 | /// confidence in the alignment actually matching the estimate. |
141 | enum class AlignmentSource { |
142 | /// The l-value was an access to a declared entity or something |
143 | /// equivalently strong, like the address of an array allocated by a |
144 | /// language runtime. |
145 | Decl, |
146 | |
147 | /// The l-value was considered opaque, so the alignment was |
148 | /// determined from a type, but that type was an explicitly-aligned |
149 | /// typedef. |
150 | AttributedType, |
151 | |
152 | /// The l-value was considered opaque, so the alignment was |
153 | /// determined from a type. |
154 | Type |
155 | }; |
156 | |
157 | /// Given that the base address has the given alignment source, what's |
158 | /// our confidence in the alignment of the field? |
159 | static inline AlignmentSource getFieldAlignmentSource(AlignmentSource Source) { |
160 | // For now, we don't distinguish fields of opaque pointers from |
161 | // top-level declarations, but maybe we should. |
162 | return AlignmentSource::Decl; |
163 | } |
164 | |
165 | class LValueBaseInfo { |
166 | AlignmentSource AlignSource; |
167 | |
168 | public: |
169 | explicit LValueBaseInfo(AlignmentSource Source = AlignmentSource::Type) |
170 | : AlignSource(Source) {} |
171 | AlignmentSource getAlignmentSource() const { return AlignSource; } |
172 | void setAlignmentSource(AlignmentSource Source) { AlignSource = Source; } |
173 | |
174 | void mergeForCast(const LValueBaseInfo &Info) { |
175 | setAlignmentSource(Info.getAlignmentSource()); |
176 | } |
177 | }; |
178 | |
179 | /// LValue - This represents an lvalue references. Because C/C++ allow |
180 | /// bitfields, this is not a simple LLVM pointer, it may be a pointer plus a |
181 | /// bitrange. |
182 | class LValue { |
183 | enum { |
184 | Simple, // This is a normal l-value, use getAddress(). |
185 | VectorElt, // This is a vector element l-value (V[i]), use getVector* |
186 | BitField, // This is a bitfield l-value, use getBitfield*. |
187 | ExtVectorElt, // This is an extended vector subset, use getExtVectorComp |
188 | GlobalReg, // This is a register l-value, use getGlobalReg() |
189 | MatrixElt // This is a matrix element, use getVector* |
190 | } LVType; |
191 | |
192 | union { |
193 | Address Addr = Address::invalid(); |
194 | llvm::Value *V; |
195 | }; |
196 | |
197 | union { |
198 | // Index into a vector subscript: V[i] |
199 | llvm::Value *VectorIdx; |
200 | |
201 | // ExtVector element subset: V.xyx |
202 | llvm::Constant *VectorElts; |
203 | |
204 | // BitField start bit and size |
205 | const CGBitFieldInfo *BitFieldInfo; |
206 | }; |
207 | |
208 | QualType Type; |
209 | |
210 | // 'const' is unused here |
211 | Qualifiers Quals; |
212 | |
213 | // objective-c's ivar |
214 | bool Ivar:1; |
215 | |
216 | // objective-c's ivar is an array |
217 | bool ObjIsArray:1; |
218 | |
219 | // LValue is non-gc'able for any reason, including being a parameter or local |
220 | // variable. |
221 | bool NonGC: 1; |
222 | |
223 | // Lvalue is a global reference of an objective-c object |
224 | bool GlobalObjCRef : 1; |
225 | |
226 | // Lvalue is a thread local reference |
227 | bool ThreadLocalRef : 1; |
228 | |
229 | // Lvalue has ARC imprecise lifetime. We store this inverted to try |
230 | // to make the default bitfield pattern all-zeroes. |
231 | bool ImpreciseLifetime : 1; |
232 | |
233 | // This flag shows if a nontemporal load/stores should be used when accessing |
234 | // this lvalue. |
235 | bool Nontemporal : 1; |
236 | |
237 | LValueBaseInfo BaseInfo; |
238 | TBAAAccessInfo TBAAInfo; |
239 | |
240 | Expr *BaseIvarExp; |
241 | |
242 | private: |
243 | void Initialize(QualType Type, Qualifiers Quals, Address Addr, |
244 | LValueBaseInfo BaseInfo, TBAAAccessInfo TBAAInfo) { |
245 | this->Type = Type; |
246 | this->Quals = Quals; |
247 | const unsigned MaxAlign = 1U << 31; |
248 | CharUnits Alignment = Addr.getAlignment(); |
249 | assert((isGlobalReg() || !Alignment.isZero() || Type->isIncompleteType()) && |
250 | "initializing l-value with zero alignment!" ); |
251 | if (Alignment.getQuantity() > MaxAlign) { |
252 | assert(false && "Alignment exceeds allowed max!" ); |
253 | Alignment = CharUnits::fromQuantity(Quantity: MaxAlign); |
254 | } |
255 | this->Addr = Addr; |
256 | this->BaseInfo = BaseInfo; |
257 | this->TBAAInfo = TBAAInfo; |
258 | |
259 | // Initialize Objective-C flags. |
260 | this->Ivar = this->ObjIsArray = this->NonGC = this->GlobalObjCRef = false; |
261 | this->ImpreciseLifetime = false; |
262 | this->Nontemporal = false; |
263 | this->ThreadLocalRef = false; |
264 | this->BaseIvarExp = nullptr; |
265 | } |
266 | |
267 | void initializeSimpleLValue(Address Addr, QualType Type, |
268 | LValueBaseInfo BaseInfo, TBAAAccessInfo TBAAInfo, |
269 | ASTContext &Context) { |
270 | Qualifiers QS = Type.getQualifiers(); |
271 | QS.setObjCGCAttr(Context.getObjCGCAttrKind(Ty: Type)); |
272 | LVType = Simple; |
273 | Initialize(Type, Quals: QS, Addr, BaseInfo, TBAAInfo); |
274 | assert(Addr.getBasePointer()->getType()->isPointerTy()); |
275 | } |
276 | |
277 | public: |
278 | bool isSimple() const { return LVType == Simple; } |
279 | bool isVectorElt() const { return LVType == VectorElt; } |
280 | bool isBitField() const { return LVType == BitField; } |
281 | bool isExtVectorElt() const { return LVType == ExtVectorElt; } |
282 | bool isGlobalReg() const { return LVType == GlobalReg; } |
283 | bool isMatrixElt() const { return LVType == MatrixElt; } |
284 | |
285 | bool isVolatileQualified() const { return Quals.hasVolatile(); } |
286 | bool isRestrictQualified() const { return Quals.hasRestrict(); } |
287 | unsigned getVRQualifiers() const { |
288 | return Quals.getCVRQualifiers() & ~Qualifiers::Const; |
289 | } |
290 | |
291 | QualType getType() const { return Type; } |
292 | |
293 | Qualifiers::ObjCLifetime getObjCLifetime() const { |
294 | return Quals.getObjCLifetime(); |
295 | } |
296 | |
297 | bool isObjCIvar() const { return Ivar; } |
298 | void setObjCIvar(bool Value) { Ivar = Value; } |
299 | |
300 | bool isObjCArray() const { return ObjIsArray; } |
301 | void setObjCArray(bool Value) { ObjIsArray = Value; } |
302 | |
303 | bool isNonGC () const { return NonGC; } |
304 | void setNonGC(bool Value) { NonGC = Value; } |
305 | |
306 | bool isGlobalObjCRef() const { return GlobalObjCRef; } |
307 | void setGlobalObjCRef(bool Value) { GlobalObjCRef = Value; } |
308 | |
309 | bool isThreadLocalRef() const { return ThreadLocalRef; } |
310 | void setThreadLocalRef(bool Value) { ThreadLocalRef = Value;} |
311 | |
312 | ARCPreciseLifetime_t isARCPreciseLifetime() const { |
313 | return ARCPreciseLifetime_t(!ImpreciseLifetime); |
314 | } |
315 | void setARCPreciseLifetime(ARCPreciseLifetime_t value) { |
316 | ImpreciseLifetime = (value == ARCImpreciseLifetime); |
317 | } |
318 | bool isNontemporal() const { return Nontemporal; } |
319 | void setNontemporal(bool Value) { Nontemporal = Value; } |
320 | |
321 | bool isObjCWeak() const { |
322 | return Quals.getObjCGCAttr() == Qualifiers::Weak; |
323 | } |
324 | bool isObjCStrong() const { |
325 | return Quals.getObjCGCAttr() == Qualifiers::Strong; |
326 | } |
327 | |
328 | bool isVolatile() const { |
329 | return Quals.hasVolatile(); |
330 | } |
331 | |
332 | Expr *getBaseIvarExp() const { return BaseIvarExp; } |
333 | void setBaseIvarExp(Expr *V) { BaseIvarExp = V; } |
334 | |
335 | TBAAAccessInfo getTBAAInfo() const { return TBAAInfo; } |
336 | void setTBAAInfo(TBAAAccessInfo Info) { TBAAInfo = Info; } |
337 | |
338 | const Qualifiers &getQuals() const { return Quals; } |
339 | Qualifiers &getQuals() { return Quals; } |
340 | |
341 | LangAS getAddressSpace() const { return Quals.getAddressSpace(); } |
342 | |
343 | CharUnits getAlignment() const { return Addr.getAlignment(); } |
344 | void setAlignment(CharUnits A) { Addr.setAlignment(A); } |
345 | |
346 | LValueBaseInfo getBaseInfo() const { return BaseInfo; } |
347 | void setBaseInfo(LValueBaseInfo Info) { BaseInfo = Info; } |
348 | |
349 | KnownNonNull_t isKnownNonNull() const { return Addr.isKnownNonNull(); } |
350 | LValue setKnownNonNull() { |
351 | Addr.setKnownNonNull(); |
352 | return *this; |
353 | } |
354 | |
355 | // simple lvalue |
356 | llvm::Value *getPointer(CodeGenFunction &CGF) const; |
357 | llvm::Value *emitResignedPointer(QualType PointeeTy, |
358 | CodeGenFunction &CGF) const; |
359 | llvm::Value *emitRawPointer(CodeGenFunction &CGF) const; |
360 | |
361 | Address getAddress() const { return Addr; } |
362 | |
363 | void setAddress(Address address) { Addr = address; } |
364 | |
365 | CGPointerAuthInfo getPointerAuthInfo() const { |
366 | return Addr.getPointerAuthInfo(); |
367 | } |
368 | |
369 | // vector elt lvalue |
370 | Address getVectorAddress() const { |
371 | assert(isVectorElt()); |
372 | return Addr; |
373 | } |
374 | llvm::Value *getRawVectorPointer(CodeGenFunction &CGF) const { |
375 | assert(isVectorElt()); |
376 | return Addr.emitRawPointer(CGF); |
377 | } |
378 | llvm::Value *getVectorPointer() const { |
379 | assert(isVectorElt()); |
380 | return Addr.getBasePointer(); |
381 | } |
382 | llvm::Value *getVectorIdx() const { |
383 | assert(isVectorElt()); |
384 | return VectorIdx; |
385 | } |
386 | |
387 | Address getMatrixAddress() const { |
388 | assert(isMatrixElt()); |
389 | return Addr; |
390 | } |
391 | llvm::Value *getMatrixPointer() const { |
392 | assert(isMatrixElt()); |
393 | return Addr.getBasePointer(); |
394 | } |
395 | llvm::Value *getMatrixIdx() const { |
396 | assert(isMatrixElt()); |
397 | return VectorIdx; |
398 | } |
399 | |
400 | // extended vector elements. |
401 | Address getExtVectorAddress() const { |
402 | assert(isExtVectorElt()); |
403 | return Addr; |
404 | } |
405 | llvm::Value *getRawExtVectorPointer(CodeGenFunction &CGF) const { |
406 | assert(isExtVectorElt()); |
407 | return Addr.emitRawPointer(CGF); |
408 | } |
409 | llvm::Constant *getExtVectorElts() const { |
410 | assert(isExtVectorElt()); |
411 | return VectorElts; |
412 | } |
413 | |
414 | // bitfield lvalue |
415 | Address getBitFieldAddress() const { |
416 | assert(isBitField()); |
417 | return Addr; |
418 | } |
419 | llvm::Value *getRawBitFieldPointer(CodeGenFunction &CGF) const { |
420 | assert(isBitField()); |
421 | return Addr.emitRawPointer(CGF); |
422 | } |
423 | |
424 | const CGBitFieldInfo &getBitFieldInfo() const { |
425 | assert(isBitField()); |
426 | return *BitFieldInfo; |
427 | } |
428 | |
429 | // global register lvalue |
430 | llvm::Value *getGlobalReg() const { assert(isGlobalReg()); return V; } |
431 | |
432 | static LValue MakeAddr(Address Addr, QualType type, ASTContext &Context, |
433 | LValueBaseInfo BaseInfo, TBAAAccessInfo TBAAInfo) { |
434 | LValue R; |
435 | R.LVType = Simple; |
436 | R.initializeSimpleLValue(Addr, Type: type, BaseInfo, TBAAInfo, Context); |
437 | R.Addr = Addr; |
438 | assert(Addr.getType()->isPointerTy()); |
439 | return R; |
440 | } |
441 | |
442 | static LValue MakeVectorElt(Address vecAddress, llvm::Value *Idx, |
443 | QualType type, LValueBaseInfo BaseInfo, |
444 | TBAAAccessInfo TBAAInfo) { |
445 | LValue R; |
446 | R.LVType = VectorElt; |
447 | R.VectorIdx = Idx; |
448 | R.Initialize(Type: type, Quals: type.getQualifiers(), Addr: vecAddress, BaseInfo, TBAAInfo); |
449 | return R; |
450 | } |
451 | |
452 | static LValue MakeExtVectorElt(Address Addr, llvm::Constant *Elts, |
453 | QualType type, LValueBaseInfo BaseInfo, |
454 | TBAAAccessInfo TBAAInfo) { |
455 | LValue R; |
456 | R.LVType = ExtVectorElt; |
457 | R.VectorElts = Elts; |
458 | R.Initialize(Type: type, Quals: type.getQualifiers(), Addr, BaseInfo, TBAAInfo); |
459 | return R; |
460 | } |
461 | |
462 | /// Create a new object to represent a bit-field access. |
463 | /// |
464 | /// \param Addr - The base address of the bit-field sequence this |
465 | /// bit-field refers to. |
466 | /// \param Info - The information describing how to perform the bit-field |
467 | /// access. |
468 | static LValue MakeBitfield(Address Addr, const CGBitFieldInfo &Info, |
469 | QualType type, LValueBaseInfo BaseInfo, |
470 | TBAAAccessInfo TBAAInfo) { |
471 | LValue R; |
472 | R.LVType = BitField; |
473 | R.BitFieldInfo = &Info; |
474 | R.Initialize(Type: type, Quals: type.getQualifiers(), Addr, BaseInfo, TBAAInfo); |
475 | return R; |
476 | } |
477 | |
478 | static LValue MakeGlobalReg(llvm::Value *V, CharUnits alignment, |
479 | QualType type) { |
480 | LValue R; |
481 | R.LVType = GlobalReg; |
482 | R.Initialize(Type: type, Quals: type.getQualifiers(), Addr: Address::invalid(), |
483 | BaseInfo: LValueBaseInfo(AlignmentSource::Decl), TBAAInfo: TBAAAccessInfo()); |
484 | R.V = V; |
485 | return R; |
486 | } |
487 | |
488 | static LValue MakeMatrixElt(Address matAddress, llvm::Value *Idx, |
489 | QualType type, LValueBaseInfo BaseInfo, |
490 | TBAAAccessInfo TBAAInfo) { |
491 | LValue R; |
492 | R.LVType = MatrixElt; |
493 | R.VectorIdx = Idx; |
494 | R.Initialize(Type: type, Quals: type.getQualifiers(), Addr: matAddress, BaseInfo, TBAAInfo); |
495 | return R; |
496 | } |
497 | |
498 | RValue asAggregateRValue() const { |
499 | return RValue::getAggregate(addr: getAddress(), isVolatile: isVolatileQualified()); |
500 | } |
501 | }; |
502 | |
503 | /// An aggregate value slot. |
504 | class AggValueSlot { |
505 | /// The address. |
506 | Address Addr; |
507 | |
508 | // Qualifiers |
509 | Qualifiers Quals; |
510 | |
511 | /// DestructedFlag - This is set to true if some external code is |
512 | /// responsible for setting up a destructor for the slot. Otherwise |
513 | /// the code which constructs it should push the appropriate cleanup. |
514 | bool DestructedFlag : 1; |
515 | |
516 | /// ObjCGCFlag - This is set to true if writing to the memory in the |
517 | /// slot might require calling an appropriate Objective-C GC |
518 | /// barrier. The exact interaction here is unnecessarily mysterious. |
519 | bool ObjCGCFlag : 1; |
520 | |
521 | /// ZeroedFlag - This is set to true if the memory in the slot is |
522 | /// known to be zero before the assignment into it. This means that |
523 | /// zero fields don't need to be set. |
524 | bool ZeroedFlag : 1; |
525 | |
526 | /// AliasedFlag - This is set to true if the slot might be aliased |
527 | /// and it's not undefined behavior to access it through such an |
528 | /// alias. Note that it's always undefined behavior to access a C++ |
529 | /// object that's under construction through an alias derived from |
530 | /// outside the construction process. |
531 | /// |
532 | /// This flag controls whether calls that produce the aggregate |
533 | /// value may be evaluated directly into the slot, or whether they |
534 | /// must be evaluated into an unaliased temporary and then memcpy'ed |
535 | /// over. Since it's invalid in general to memcpy a non-POD C++ |
536 | /// object, it's important that this flag never be set when |
537 | /// evaluating an expression which constructs such an object. |
538 | bool AliasedFlag : 1; |
539 | |
540 | /// This is set to true if the tail padding of this slot might overlap |
541 | /// another object that may have already been initialized (and whose |
542 | /// value must be preserved by this initialization). If so, we may only |
543 | /// store up to the dsize of the type. Otherwise we can widen stores to |
544 | /// the size of the type. |
545 | bool OverlapFlag : 1; |
546 | |
547 | /// If is set to true, sanitizer checks are already generated for this address |
548 | /// or not required. For instance, if this address represents an object |
549 | /// created in 'new' expression, sanitizer checks for memory is made as a part |
550 | /// of 'operator new' emission and object constructor should not generate |
551 | /// them. |
552 | bool SanitizerCheckedFlag : 1; |
553 | |
554 | AggValueSlot(Address Addr, Qualifiers Quals, bool DestructedFlag, |
555 | bool ObjCGCFlag, bool ZeroedFlag, bool AliasedFlag, |
556 | bool OverlapFlag, bool SanitizerCheckedFlag) |
557 | : Addr(Addr), Quals(Quals), DestructedFlag(DestructedFlag), |
558 | ObjCGCFlag(ObjCGCFlag), ZeroedFlag(ZeroedFlag), |
559 | AliasedFlag(AliasedFlag), OverlapFlag(OverlapFlag), |
560 | SanitizerCheckedFlag(SanitizerCheckedFlag) {} |
561 | |
562 | public: |
563 | enum IsAliased_t { IsNotAliased, IsAliased }; |
564 | enum IsDestructed_t { IsNotDestructed, IsDestructed }; |
565 | enum IsZeroed_t { IsNotZeroed, IsZeroed }; |
566 | enum Overlap_t { DoesNotOverlap, MayOverlap }; |
567 | enum NeedsGCBarriers_t { DoesNotNeedGCBarriers, NeedsGCBarriers }; |
568 | enum IsSanitizerChecked_t { IsNotSanitizerChecked, IsSanitizerChecked }; |
569 | |
570 | /// ignored - Returns an aggregate value slot indicating that the |
571 | /// aggregate value is being ignored. |
572 | static AggValueSlot ignored() { |
573 | return forAddr(addr: Address::invalid(), quals: Qualifiers(), isDestructed: IsNotDestructed, |
574 | needsGC: DoesNotNeedGCBarriers, isAliased: IsNotAliased, mayOverlap: DoesNotOverlap); |
575 | } |
576 | |
577 | /// forAddr - Make a slot for an aggregate value. |
578 | /// |
579 | /// \param quals - The qualifiers that dictate how the slot should |
580 | /// be initialied. Only 'volatile' and the Objective-C lifetime |
581 | /// qualifiers matter. |
582 | /// |
583 | /// \param isDestructed - true if something else is responsible |
584 | /// for calling destructors on this object |
585 | /// \param needsGC - true if the slot is potentially located |
586 | /// somewhere that ObjC GC calls should be emitted for |
587 | static AggValueSlot forAddr(Address addr, |
588 | Qualifiers quals, |
589 | IsDestructed_t isDestructed, |
590 | NeedsGCBarriers_t needsGC, |
591 | IsAliased_t isAliased, |
592 | Overlap_t mayOverlap, |
593 | IsZeroed_t isZeroed = IsNotZeroed, |
594 | IsSanitizerChecked_t isChecked = IsNotSanitizerChecked) { |
595 | if (addr.isValid()) |
596 | addr.setKnownNonNull(); |
597 | return AggValueSlot(addr, quals, isDestructed, needsGC, isZeroed, isAliased, |
598 | mayOverlap, isChecked); |
599 | } |
600 | |
601 | static AggValueSlot |
602 | forLValue(const LValue &LV, IsDestructed_t isDestructed, |
603 | NeedsGCBarriers_t needsGC, IsAliased_t isAliased, |
604 | Overlap_t mayOverlap, IsZeroed_t isZeroed = IsNotZeroed, |
605 | IsSanitizerChecked_t isChecked = IsNotSanitizerChecked) { |
606 | return forAddr(addr: LV.getAddress(), quals: LV.getQuals(), isDestructed, needsGC, |
607 | isAliased, mayOverlap, isZeroed, isChecked); |
608 | } |
609 | |
610 | IsDestructed_t isExternallyDestructed() const { |
611 | return IsDestructed_t(DestructedFlag); |
612 | } |
613 | void setExternallyDestructed(bool destructed = true) { |
614 | DestructedFlag = destructed; |
615 | } |
616 | |
617 | Qualifiers getQualifiers() const { return Quals; } |
618 | |
619 | bool isVolatile() const { |
620 | return Quals.hasVolatile(); |
621 | } |
622 | |
623 | void setVolatile(bool flag) { |
624 | if (flag) |
625 | Quals.addVolatile(); |
626 | else |
627 | Quals.removeVolatile(); |
628 | } |
629 | |
630 | Qualifiers::ObjCLifetime getObjCLifetime() const { |
631 | return Quals.getObjCLifetime(); |
632 | } |
633 | |
634 | NeedsGCBarriers_t requiresGCollection() const { |
635 | return NeedsGCBarriers_t(ObjCGCFlag); |
636 | } |
637 | |
638 | llvm::Value *getPointer(QualType PointeeTy, CodeGenFunction &CGF) const; |
639 | |
640 | llvm::Value *emitRawPointer(CodeGenFunction &CGF) const { |
641 | return Addr.isValid() ? Addr.emitRawPointer(CGF) : nullptr; |
642 | } |
643 | |
644 | Address getAddress() const { |
645 | return Addr; |
646 | } |
647 | |
648 | bool isIgnored() const { return !Addr.isValid(); } |
649 | |
650 | CharUnits getAlignment() const { |
651 | return Addr.getAlignment(); |
652 | } |
653 | |
654 | IsAliased_t isPotentiallyAliased() const { |
655 | return IsAliased_t(AliasedFlag); |
656 | } |
657 | |
658 | Overlap_t mayOverlap() const { |
659 | return Overlap_t(OverlapFlag); |
660 | } |
661 | |
662 | bool isSanitizerChecked() const { |
663 | return SanitizerCheckedFlag; |
664 | } |
665 | |
666 | RValue asRValue() const { |
667 | if (isIgnored()) { |
668 | return RValue::getIgnored(); |
669 | } else { |
670 | return RValue::getAggregate(addr: getAddress(), isVolatile: isVolatile()); |
671 | } |
672 | } |
673 | |
674 | void setZeroed(bool V = true) { ZeroedFlag = V; } |
675 | IsZeroed_t isZeroed() const { |
676 | return IsZeroed_t(ZeroedFlag); |
677 | } |
678 | |
679 | /// Get the preferred size to use when storing a value to this slot. This |
680 | /// is the type size unless that might overlap another object, in which |
681 | /// case it's the dsize. |
682 | CharUnits getPreferredSize(ASTContext &Ctx, QualType Type) const { |
683 | return mayOverlap() ? Ctx.getTypeInfoDataSizeInChars(T: Type).Width |
684 | : Ctx.getTypeSizeInChars(T: Type); |
685 | } |
686 | }; |
687 | |
688 | } // end namespace CodeGen |
689 | } // end namespace clang |
690 | |
691 | #endif |
692 | |