1 | //===-- CGCleanup.h - Classes for cleanups IR generation --------*- 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 support the generation of LLVM IR for cleanups. |
10 | // |
11 | //===----------------------------------------------------------------------===// |
12 | |
13 | #ifndef LLVM_CLANG_LIB_CODEGEN_CGCLEANUP_H |
14 | #define LLVM_CLANG_LIB_CODEGEN_CGCLEANUP_H |
15 | |
16 | #include "EHScopeStack.h" |
17 | |
18 | #include "Address.h" |
19 | #include "llvm/ADT/STLExtras.h" |
20 | #include "llvm/ADT/SetVector.h" |
21 | #include "llvm/ADT/SmallPtrSet.h" |
22 | #include "llvm/ADT/SmallVector.h" |
23 | #include "llvm/IR/Instruction.h" |
24 | |
25 | namespace llvm { |
26 | class BasicBlock; |
27 | class Value; |
28 | class ConstantInt; |
29 | } |
30 | |
31 | namespace clang { |
32 | class FunctionDecl; |
33 | namespace CodeGen { |
34 | class CodeGenModule; |
35 | class CodeGenFunction; |
36 | |
37 | /// The MS C++ ABI needs a pointer to RTTI data plus some flags to describe the |
38 | /// type of a catch handler, so we use this wrapper. |
39 | struct CatchTypeInfo { |
40 | llvm::Constant *RTTI; |
41 | unsigned Flags; |
42 | }; |
43 | |
44 | /// A protected scope for zero-cost EH handling. |
45 | class EHScope { |
46 | public: |
47 | enum Kind { Cleanup, Catch, Terminate, Filter }; |
48 | |
49 | private: |
50 | llvm::BasicBlock *CachedLandingPad; |
51 | llvm::BasicBlock *CachedEHDispatchBlock; |
52 | |
53 | EHScopeStack::stable_iterator EnclosingEHScope; |
54 | |
55 | class CommonBitFields { |
56 | friend class EHScope; |
57 | LLVM_PREFERRED_TYPE(Kind) |
58 | unsigned Kind : 3; |
59 | }; |
60 | enum { NumCommonBits = 3 }; |
61 | |
62 | protected: |
63 | class CatchBitFields { |
64 | friend class EHCatchScope; |
65 | unsigned : NumCommonBits; |
66 | |
67 | unsigned NumHandlers : 32 - NumCommonBits; |
68 | }; |
69 | |
70 | class CleanupBitFields { |
71 | friend class EHCleanupScope; |
72 | unsigned : NumCommonBits; |
73 | |
74 | /// Whether this cleanup needs to be run along normal edges. |
75 | LLVM_PREFERRED_TYPE(bool) |
76 | unsigned IsNormalCleanup : 1; |
77 | |
78 | /// Whether this cleanup needs to be run along exception edges. |
79 | LLVM_PREFERRED_TYPE(bool) |
80 | unsigned IsEHCleanup : 1; |
81 | |
82 | /// Whether this cleanup is currently active. |
83 | LLVM_PREFERRED_TYPE(bool) |
84 | unsigned IsActive : 1; |
85 | |
86 | /// Whether this cleanup is a lifetime marker |
87 | LLVM_PREFERRED_TYPE(bool) |
88 | unsigned IsLifetimeMarker : 1; |
89 | |
90 | /// Whether this cleanup is a fake use |
91 | LLVM_PREFERRED_TYPE(bool) |
92 | unsigned IsFakeUse : 1; |
93 | |
94 | /// Whether the normal cleanup should test the activation flag. |
95 | LLVM_PREFERRED_TYPE(bool) |
96 | unsigned TestFlagInNormalCleanup : 1; |
97 | |
98 | /// Whether the EH cleanup should test the activation flag. |
99 | LLVM_PREFERRED_TYPE(bool) |
100 | unsigned TestFlagInEHCleanup : 1; |
101 | |
102 | /// The amount of extra storage needed by the Cleanup. |
103 | /// Always a multiple of the scope-stack alignment. |
104 | unsigned CleanupSize : 12; |
105 | }; |
106 | |
107 | class FilterBitFields { |
108 | friend class EHFilterScope; |
109 | unsigned : NumCommonBits; |
110 | |
111 | unsigned NumFilters : 32 - NumCommonBits; |
112 | }; |
113 | |
114 | union { |
115 | CommonBitFields CommonBits; |
116 | CatchBitFields CatchBits; |
117 | CleanupBitFields CleanupBits; |
118 | FilterBitFields FilterBits; |
119 | }; |
120 | |
121 | public: |
122 | EHScope(Kind kind, EHScopeStack::stable_iterator enclosingEHScope) |
123 | : CachedLandingPad(nullptr), CachedEHDispatchBlock(nullptr), |
124 | EnclosingEHScope(enclosingEHScope) { |
125 | CommonBits.Kind = kind; |
126 | } |
127 | |
128 | Kind getKind() const { return static_cast<Kind>(CommonBits.Kind); } |
129 | |
130 | llvm::BasicBlock *getCachedLandingPad() const { |
131 | return CachedLandingPad; |
132 | } |
133 | |
134 | void setCachedLandingPad(llvm::BasicBlock *block) { |
135 | CachedLandingPad = block; |
136 | } |
137 | |
138 | llvm::BasicBlock *getCachedEHDispatchBlock() const { |
139 | return CachedEHDispatchBlock; |
140 | } |
141 | |
142 | void setCachedEHDispatchBlock(llvm::BasicBlock *block) { |
143 | CachedEHDispatchBlock = block; |
144 | } |
145 | |
146 | bool hasEHBranches() const { |
147 | if (llvm::BasicBlock *block = getCachedEHDispatchBlock()) |
148 | return !block->use_empty(); |
149 | return false; |
150 | } |
151 | |
152 | EHScopeStack::stable_iterator getEnclosingEHScope() const { |
153 | return EnclosingEHScope; |
154 | } |
155 | }; |
156 | |
157 | /// A scope which attempts to handle some, possibly all, types of |
158 | /// exceptions. |
159 | /// |
160 | /// Objective C \@finally blocks are represented using a cleanup scope |
161 | /// after the catch scope. |
162 | class EHCatchScope : public EHScope { |
163 | // In effect, we have a flexible array member |
164 | // Handler Handlers[0]; |
165 | // But that's only standard in C99, not C++, so we have to do |
166 | // annoying pointer arithmetic instead. |
167 | |
168 | public: |
169 | struct Handler { |
170 | /// A type info value, or null (C++ null, not an LLVM null pointer) |
171 | /// for a catch-all. |
172 | CatchTypeInfo Type; |
173 | |
174 | /// The catch handler for this type. |
175 | llvm::BasicBlock *Block; |
176 | |
177 | bool isCatchAll() const { return Type.RTTI == nullptr; } |
178 | }; |
179 | |
180 | private: |
181 | friend class EHScopeStack; |
182 | |
183 | Handler *getHandlers() { |
184 | return reinterpret_cast<Handler*>(this+1); |
185 | } |
186 | |
187 | const Handler *getHandlers() const { |
188 | return reinterpret_cast<const Handler*>(this+1); |
189 | } |
190 | |
191 | public: |
192 | static size_t getSizeForNumHandlers(unsigned N) { |
193 | return sizeof(EHCatchScope) + N * sizeof(Handler); |
194 | } |
195 | |
196 | EHCatchScope(unsigned numHandlers, |
197 | EHScopeStack::stable_iterator enclosingEHScope) |
198 | : EHScope(Catch, enclosingEHScope) { |
199 | CatchBits.NumHandlers = numHandlers; |
200 | assert(CatchBits.NumHandlers == numHandlers && "NumHandlers overflow?"); |
201 | } |
202 | |
203 | unsigned getNumHandlers() const { |
204 | return CatchBits.NumHandlers; |
205 | } |
206 | |
207 | void setCatchAllHandler(unsigned I, llvm::BasicBlock *Block) { |
208 | setHandler(I, Type: CatchTypeInfo{.RTTI: nullptr, .Flags: 0}, Block); |
209 | } |
210 | |
211 | void setHandler(unsigned I, llvm::Constant *Type, llvm::BasicBlock *Block) { |
212 | assert(I < getNumHandlers()); |
213 | getHandlers()[I].Type = CatchTypeInfo{.RTTI: Type, .Flags: 0}; |
214 | getHandlers()[I].Block = Block; |
215 | } |
216 | |
217 | void setHandler(unsigned I, CatchTypeInfo Type, llvm::BasicBlock *Block) { |
218 | assert(I < getNumHandlers()); |
219 | getHandlers()[I].Type = Type; |
220 | getHandlers()[I].Block = Block; |
221 | } |
222 | |
223 | const Handler &getHandler(unsigned I) const { |
224 | assert(I < getNumHandlers()); |
225 | return getHandlers()[I]; |
226 | } |
227 | |
228 | // Clear all handler blocks. |
229 | // FIXME: it's better to always call clearHandlerBlocks in DTOR and have a |
230 | // 'takeHandler' or some such function which removes ownership from the |
231 | // EHCatchScope object if the handlers should live longer than EHCatchScope. |
232 | void clearHandlerBlocks() { |
233 | for (unsigned I = 0, N = getNumHandlers(); I != N; ++I) |
234 | delete getHandler(I).Block; |
235 | } |
236 | |
237 | typedef const Handler *iterator; |
238 | iterator begin() const { return getHandlers(); } |
239 | iterator end() const { return getHandlers() + getNumHandlers(); } |
240 | |
241 | static bool classof(const EHScope *Scope) { |
242 | return Scope->getKind() == Catch; |
243 | } |
244 | }; |
245 | |
246 | /// A cleanup scope which generates the cleanup blocks lazily. |
247 | class alignas(8) EHCleanupScope : public EHScope { |
248 | /// The nearest normal cleanup scope enclosing this one. |
249 | EHScopeStack::stable_iterator EnclosingNormal; |
250 | |
251 | /// The nearest EH scope enclosing this one. |
252 | EHScopeStack::stable_iterator EnclosingEH; |
253 | |
254 | /// The dual entry/exit block along the normal edge. This is lazily |
255 | /// created if needed before the cleanup is popped. |
256 | llvm::BasicBlock *NormalBlock; |
257 | |
258 | /// An optional i1 variable indicating whether this cleanup has been |
259 | /// activated yet. |
260 | Address ActiveFlag; |
261 | |
262 | /// Extra information required for cleanups that have resolved |
263 | /// branches through them. This has to be allocated on the side |
264 | /// because everything on the cleanup stack has be trivially |
265 | /// movable. |
266 | struct ExtInfo { |
267 | /// The destinations of normal branch-afters and branch-throughs. |
268 | llvm::SmallPtrSet<llvm::BasicBlock*, 4> Branches; |
269 | |
270 | /// Normal branch-afters. |
271 | SmallVector<std::pair<llvm::BasicBlock*,llvm::ConstantInt*>, 4> |
272 | BranchAfters; |
273 | }; |
274 | mutable struct ExtInfo *ExtInfo; |
275 | |
276 | /// Erases auxillary allocas and their usages for an unused cleanup. |
277 | /// Cleanups should mark these allocas as 'used' if the cleanup is |
278 | /// emitted, otherwise these instructions would be erased. |
279 | struct AuxillaryAllocas { |
280 | SmallVector<llvm::Instruction *, 1> AuxAllocas; |
281 | bool used = false; |
282 | |
283 | // Records a potentially unused instruction to be erased later. |
284 | void Add(llvm::AllocaInst *Alloca) { AuxAllocas.push_back(Elt: Alloca); } |
285 | |
286 | // Mark all recorded instructions as used. These will not be erased later. |
287 | void MarkUsed() { |
288 | used = true; |
289 | AuxAllocas.clear(); |
290 | } |
291 | |
292 | ~AuxillaryAllocas() { |
293 | if (used) |
294 | return; |
295 | llvm::SetVector<llvm::Instruction *> Uses; |
296 | for (auto *Inst : llvm::reverse(C&: AuxAllocas)) |
297 | CollectUses(I: Inst, Uses); |
298 | // Delete uses in the reverse order of insertion. |
299 | for (auto *I : llvm::reverse(C&: Uses)) |
300 | I->eraseFromParent(); |
301 | } |
302 | |
303 | private: |
304 | void CollectUses(llvm::Instruction *I, |
305 | llvm::SetVector<llvm::Instruction *> &Uses) { |
306 | if (!I || !Uses.insert(X: I)) |
307 | return; |
308 | for (auto *User : I->users()) |
309 | CollectUses(I: cast<llvm::Instruction>(Val: User), Uses); |
310 | } |
311 | }; |
312 | mutable struct AuxillaryAllocas *AuxAllocas; |
313 | |
314 | AuxillaryAllocas &getAuxillaryAllocas() { |
315 | if (!AuxAllocas) { |
316 | AuxAllocas = new struct AuxillaryAllocas(); |
317 | } |
318 | return *AuxAllocas; |
319 | } |
320 | |
321 | /// The number of fixups required by enclosing scopes (not including |
322 | /// this one). If this is the top cleanup scope, all the fixups |
323 | /// from this index onwards belong to this scope. |
324 | unsigned FixupDepth; |
325 | |
326 | struct ExtInfo &getExtInfo() { |
327 | if (!ExtInfo) ExtInfo = new struct ExtInfo(); |
328 | return *ExtInfo; |
329 | } |
330 | |
331 | const struct ExtInfo &getExtInfo() const { |
332 | if (!ExtInfo) ExtInfo = new struct ExtInfo(); |
333 | return *ExtInfo; |
334 | } |
335 | |
336 | public: |
337 | /// Gets the size required for a lazy cleanup scope with the given |
338 | /// cleanup-data requirements. |
339 | static size_t getSizeForCleanupSize(size_t Size) { |
340 | return sizeof(EHCleanupScope) + Size; |
341 | } |
342 | |
343 | size_t getAllocatedSize() const { |
344 | return sizeof(EHCleanupScope) + CleanupBits.CleanupSize; |
345 | } |
346 | |
347 | EHCleanupScope(bool isNormal, bool isEH, unsigned cleanupSize, |
348 | unsigned fixupDepth, |
349 | EHScopeStack::stable_iterator enclosingNormal, |
350 | EHScopeStack::stable_iterator enclosingEH) |
351 | : EHScope(EHScope::Cleanup, enclosingEH), |
352 | EnclosingNormal(enclosingNormal), NormalBlock(nullptr), |
353 | ActiveFlag(Address::invalid()), ExtInfo(nullptr), AuxAllocas(nullptr), |
354 | FixupDepth(fixupDepth) { |
355 | CleanupBits.IsNormalCleanup = isNormal; |
356 | CleanupBits.IsEHCleanup = isEH; |
357 | CleanupBits.IsActive = true; |
358 | CleanupBits.IsLifetimeMarker = false; |
359 | CleanupBits.IsFakeUse = false; |
360 | CleanupBits.TestFlagInNormalCleanup = false; |
361 | CleanupBits.TestFlagInEHCleanup = false; |
362 | CleanupBits.CleanupSize = cleanupSize; |
363 | |
364 | assert(CleanupBits.CleanupSize == cleanupSize && "cleanup size overflow"); |
365 | } |
366 | |
367 | void Destroy() { |
368 | if (AuxAllocas) |
369 | delete AuxAllocas; |
370 | delete ExtInfo; |
371 | } |
372 | void AddAuxAllocas(llvm::SmallVector<llvm::AllocaInst *> Allocas) { |
373 | for (auto *Alloca : Allocas) |
374 | getAuxillaryAllocas().Add(Alloca); |
375 | } |
376 | void MarkEmitted() { getAuxillaryAllocas().MarkUsed(); } |
377 | // Objects of EHCleanupScope are not destructed. Use Destroy(). |
378 | ~EHCleanupScope() = delete; |
379 | |
380 | bool isNormalCleanup() const { return CleanupBits.IsNormalCleanup; } |
381 | llvm::BasicBlock *getNormalBlock() const { return NormalBlock; } |
382 | void setNormalBlock(llvm::BasicBlock *BB) { NormalBlock = BB; } |
383 | |
384 | bool isEHCleanup() const { return CleanupBits.IsEHCleanup; } |
385 | |
386 | bool isActive() const { return CleanupBits.IsActive; } |
387 | void setActive(bool A) { CleanupBits.IsActive = A; } |
388 | |
389 | bool isLifetimeMarker() const { return CleanupBits.IsLifetimeMarker; } |
390 | void setLifetimeMarker() { CleanupBits.IsLifetimeMarker = true; } |
391 | |
392 | bool isFakeUse() const { return CleanupBits.IsFakeUse; } |
393 | void setFakeUse() { CleanupBits.IsFakeUse = true; } |
394 | |
395 | bool hasActiveFlag() const { return ActiveFlag.isValid(); } |
396 | Address getActiveFlag() const { |
397 | return ActiveFlag; |
398 | } |
399 | void setActiveFlag(RawAddress Var) { |
400 | assert(Var.getAlignment().isOne()); |
401 | ActiveFlag = Var; |
402 | } |
403 | |
404 | void setTestFlagInNormalCleanup() { |
405 | CleanupBits.TestFlagInNormalCleanup = true; |
406 | } |
407 | bool shouldTestFlagInNormalCleanup() const { |
408 | return CleanupBits.TestFlagInNormalCleanup; |
409 | } |
410 | |
411 | void setTestFlagInEHCleanup() { |
412 | CleanupBits.TestFlagInEHCleanup = true; |
413 | } |
414 | bool shouldTestFlagInEHCleanup() const { |
415 | return CleanupBits.TestFlagInEHCleanup; |
416 | } |
417 | |
418 | unsigned getFixupDepth() const { return FixupDepth; } |
419 | EHScopeStack::stable_iterator getEnclosingNormalCleanup() const { |
420 | return EnclosingNormal; |
421 | } |
422 | |
423 | size_t getCleanupSize() const { return CleanupBits.CleanupSize; } |
424 | void *getCleanupBuffer() { return this + 1; } |
425 | |
426 | EHScopeStack::Cleanup *getCleanup() { |
427 | return reinterpret_cast<EHScopeStack::Cleanup*>(getCleanupBuffer()); |
428 | } |
429 | |
430 | /// True if this cleanup scope has any branch-afters or branch-throughs. |
431 | bool hasBranches() const { return ExtInfo && !ExtInfo->Branches.empty(); } |
432 | |
433 | /// Add a branch-after to this cleanup scope. A branch-after is a |
434 | /// branch from a point protected by this (normal) cleanup to a |
435 | /// point in the normal cleanup scope immediately containing it. |
436 | /// For example, |
437 | /// for (;;) { A a; break; } |
438 | /// contains a branch-after. |
439 | /// |
440 | /// Branch-afters each have their own destination out of the |
441 | /// cleanup, guaranteed distinct from anything else threaded through |
442 | /// it. Therefore branch-afters usually force a switch after the |
443 | /// cleanup. |
444 | void addBranchAfter(llvm::ConstantInt *Index, |
445 | llvm::BasicBlock *Block) { |
446 | struct ExtInfo &ExtInfo = getExtInfo(); |
447 | if (ExtInfo.Branches.insert(Ptr: Block).second) |
448 | ExtInfo.BranchAfters.push_back(Elt: std::make_pair(x&: Block, y&: Index)); |
449 | } |
450 | |
451 | /// Return the number of unique branch-afters on this scope. |
452 | unsigned getNumBranchAfters() const { |
453 | return ExtInfo ? ExtInfo->BranchAfters.size() : 0; |
454 | } |
455 | |
456 | llvm::BasicBlock *getBranchAfterBlock(unsigned I) const { |
457 | assert(I < getNumBranchAfters()); |
458 | return ExtInfo->BranchAfters[I].first; |
459 | } |
460 | |
461 | llvm::ConstantInt *getBranchAfterIndex(unsigned I) const { |
462 | assert(I < getNumBranchAfters()); |
463 | return ExtInfo->BranchAfters[I].second; |
464 | } |
465 | |
466 | /// Add a branch-through to this cleanup scope. A branch-through is |
467 | /// a branch from a scope protected by this (normal) cleanup to an |
468 | /// enclosing scope other than the immediately-enclosing normal |
469 | /// cleanup scope. |
470 | /// |
471 | /// In the following example, the branch through B's scope is a |
472 | /// branch-through, while the branch through A's scope is a |
473 | /// branch-after: |
474 | /// for (;;) { A a; B b; break; } |
475 | /// |
476 | /// All branch-throughs have a common destination out of the |
477 | /// cleanup, one possibly shared with the fall-through. Therefore |
478 | /// branch-throughs usually don't force a switch after the cleanup. |
479 | /// |
480 | /// \return true if the branch-through was new to this scope |
481 | bool addBranchThrough(llvm::BasicBlock *Block) { |
482 | return getExtInfo().Branches.insert(Ptr: Block).second; |
483 | } |
484 | |
485 | /// Determines if this cleanup scope has any branch throughs. |
486 | bool hasBranchThroughs() const { |
487 | if (!ExtInfo) return false; |
488 | return (ExtInfo->BranchAfters.size() != ExtInfo->Branches.size()); |
489 | } |
490 | |
491 | static bool classof(const EHScope *Scope) { |
492 | return (Scope->getKind() == Cleanup); |
493 | } |
494 | }; |
495 | // NOTE: there's a bunch of different data classes tacked on after an |
496 | // EHCleanupScope. It is asserted (in EHScopeStack::pushCleanup*) that |
497 | // they don't require greater alignment than ScopeStackAlignment. So, |
498 | // EHCleanupScope ought to have alignment equal to that -- not more |
499 | // (would be misaligned by the stack allocator), and not less (would |
500 | // break the appended classes). |
501 | static_assert(alignof(EHCleanupScope) == EHScopeStack::ScopeStackAlignment, |
502 | "EHCleanupScope expected alignment"); |
503 | |
504 | /// An exceptions scope which filters exceptions thrown through it. |
505 | /// Only exceptions matching the filter types will be permitted to be |
506 | /// thrown. |
507 | /// |
508 | /// This is used to implement C++ exception specifications. |
509 | class EHFilterScope : public EHScope { |
510 | // Essentially ends in a flexible array member: |
511 | // llvm::Value *FilterTypes[0]; |
512 | |
513 | llvm::Value **getFilters() { |
514 | return reinterpret_cast<llvm::Value**>(this+1); |
515 | } |
516 | |
517 | llvm::Value * const *getFilters() const { |
518 | return reinterpret_cast<llvm::Value* const *>(this+1); |
519 | } |
520 | |
521 | public: |
522 | EHFilterScope(unsigned numFilters) |
523 | : EHScope(Filter, EHScopeStack::stable_end()) { |
524 | FilterBits.NumFilters = numFilters; |
525 | assert(FilterBits.NumFilters == numFilters && "NumFilters overflow"); |
526 | } |
527 | |
528 | static size_t getSizeForNumFilters(unsigned numFilters) { |
529 | return sizeof(EHFilterScope) + numFilters * sizeof(llvm::Value*); |
530 | } |
531 | |
532 | unsigned getNumFilters() const { return FilterBits.NumFilters; } |
533 | |
534 | void setFilter(unsigned i, llvm::Value *filterValue) { |
535 | assert(i < getNumFilters()); |
536 | getFilters()[i] = filterValue; |
537 | } |
538 | |
539 | llvm::Value *getFilter(unsigned i) const { |
540 | assert(i < getNumFilters()); |
541 | return getFilters()[i]; |
542 | } |
543 | |
544 | static bool classof(const EHScope *scope) { |
545 | return scope->getKind() == Filter; |
546 | } |
547 | }; |
548 | |
549 | /// An exceptions scope which calls std::terminate if any exception |
550 | /// reaches it. |
551 | class EHTerminateScope : public EHScope { |
552 | public: |
553 | EHTerminateScope(EHScopeStack::stable_iterator enclosingEHScope) |
554 | : EHScope(Terminate, enclosingEHScope) {} |
555 | static size_t getSize() { return sizeof(EHTerminateScope); } |
556 | |
557 | static bool classof(const EHScope *scope) { |
558 | return scope->getKind() == Terminate; |
559 | } |
560 | }; |
561 | |
562 | /// A non-stable pointer into the scope stack. |
563 | class EHScopeStack::iterator { |
564 | char *Ptr; |
565 | |
566 | friend class EHScopeStack; |
567 | explicit iterator(char *Ptr) : Ptr(Ptr) {} |
568 | |
569 | public: |
570 | iterator() : Ptr(nullptr) {} |
571 | |
572 | EHScope *get() const { |
573 | return reinterpret_cast<EHScope*>(Ptr); |
574 | } |
575 | |
576 | EHScope *operator->() const { return get(); } |
577 | EHScope &operator*() const { return *get(); } |
578 | |
579 | iterator &operator++() { |
580 | size_t Size; |
581 | switch (get()->getKind()) { |
582 | case EHScope::Catch: |
583 | Size = EHCatchScope::getSizeForNumHandlers( |
584 | N: static_cast<const EHCatchScope *>(get())->getNumHandlers()); |
585 | break; |
586 | |
587 | case EHScope::Filter: |
588 | Size = EHFilterScope::getSizeForNumFilters( |
589 | numFilters: static_cast<const EHFilterScope *>(get())->getNumFilters()); |
590 | break; |
591 | |
592 | case EHScope::Cleanup: |
593 | Size = static_cast<const EHCleanupScope *>(get())->getAllocatedSize(); |
594 | break; |
595 | |
596 | case EHScope::Terminate: |
597 | Size = EHTerminateScope::getSize(); |
598 | break; |
599 | } |
600 | Ptr += llvm::alignTo(Value: Size, Align: ScopeStackAlignment); |
601 | return *this; |
602 | } |
603 | |
604 | iterator next() { |
605 | iterator copy = *this; |
606 | ++copy; |
607 | return copy; |
608 | } |
609 | |
610 | iterator operator++(int) { |
611 | iterator copy = *this; |
612 | operator++(); |
613 | return copy; |
614 | } |
615 | |
616 | bool encloses(iterator other) const { return Ptr >= other.Ptr; } |
617 | bool strictlyEncloses(iterator other) const { return Ptr > other.Ptr; } |
618 | |
619 | bool operator==(iterator other) const { return Ptr == other.Ptr; } |
620 | bool operator!=(iterator other) const { return Ptr != other.Ptr; } |
621 | }; |
622 | |
623 | inline EHScopeStack::iterator EHScopeStack::begin() const { |
624 | return iterator(StartOfData); |
625 | } |
626 | |
627 | inline EHScopeStack::iterator EHScopeStack::end() const { |
628 | return iterator(EndOfBuffer); |
629 | } |
630 | |
631 | inline void EHScopeStack::popCatch() { |
632 | assert(!empty() && "popping exception stack when not empty"); |
633 | |
634 | EHCatchScope &scope = cast<EHCatchScope>(Val&: *begin()); |
635 | InnermostEHScope = scope.getEnclosingEHScope(); |
636 | deallocate(Size: EHCatchScope::getSizeForNumHandlers(N: scope.getNumHandlers())); |
637 | } |
638 | |
639 | inline void EHScopeStack::popTerminate() { |
640 | assert(!empty() && "popping exception stack when not empty"); |
641 | |
642 | EHTerminateScope &scope = cast<EHTerminateScope>(Val&: *begin()); |
643 | InnermostEHScope = scope.getEnclosingEHScope(); |
644 | deallocate(Size: EHTerminateScope::getSize()); |
645 | } |
646 | |
647 | inline EHScopeStack::iterator EHScopeStack::find(stable_iterator sp) const { |
648 | assert(sp.isValid() && "finding invalid savepoint"); |
649 | assert(sp.Size <= stable_begin().Size && "finding savepoint after pop"); |
650 | return iterator(EndOfBuffer - sp.Size); |
651 | } |
652 | |
653 | inline EHScopeStack::stable_iterator |
654 | EHScopeStack::stabilize(iterator ir) const { |
655 | assert(StartOfData <= ir.Ptr && ir.Ptr <= EndOfBuffer); |
656 | return stable_iterator(EndOfBuffer - ir.Ptr); |
657 | } |
658 | |
659 | /// The exceptions personality for a function. |
660 | struct EHPersonality { |
661 | const char *PersonalityFn; |
662 | |
663 | // If this is non-null, this personality requires a non-standard |
664 | // function for rethrowing an exception after a catchall cleanup. |
665 | // This function must have prototype void(void*). |
666 | const char *CatchallRethrowFn; |
667 | |
668 | static const EHPersonality &get(CodeGenModule &CGM, const FunctionDecl *FD); |
669 | static const EHPersonality &get(CodeGenFunction &CGF); |
670 | |
671 | static const EHPersonality GNU_C; |
672 | static const EHPersonality GNU_C_SJLJ; |
673 | static const EHPersonality GNU_C_SEH; |
674 | static const EHPersonality GNU_ObjC; |
675 | static const EHPersonality GNU_ObjC_SJLJ; |
676 | static const EHPersonality GNU_ObjC_SEH; |
677 | static const EHPersonality GNUstep_ObjC; |
678 | static const EHPersonality GNU_ObjCXX; |
679 | static const EHPersonality NeXT_ObjC; |
680 | static const EHPersonality GNU_CPlusPlus; |
681 | static const EHPersonality GNU_CPlusPlus_SJLJ; |
682 | static const EHPersonality GNU_CPlusPlus_SEH; |
683 | static const EHPersonality MSVC_except_handler; |
684 | static const EHPersonality MSVC_C_specific_handler; |
685 | static const EHPersonality MSVC_CxxFrameHandler3; |
686 | static const EHPersonality GNU_Wasm_CPlusPlus; |
687 | static const EHPersonality XL_CPlusPlus; |
688 | static const EHPersonality ZOS_CPlusPlus; |
689 | |
690 | /// Does this personality use landingpads or the family of pad instructions |
691 | /// designed to form funclets? |
692 | bool usesFuncletPads() const { |
693 | return isMSVCPersonality() || isWasmPersonality(); |
694 | } |
695 | |
696 | bool isMSVCPersonality() const { |
697 | return this == &MSVC_except_handler || this == &MSVC_C_specific_handler || |
698 | this == &MSVC_CxxFrameHandler3; |
699 | } |
700 | |
701 | bool isWasmPersonality() const { return this == &GNU_Wasm_CPlusPlus; } |
702 | |
703 | bool isMSVCXXPersonality() const { return this == &MSVC_CxxFrameHandler3; } |
704 | }; |
705 | } |
706 | } |
707 | |
708 | #endif |
709 |
Definitions
- CatchTypeInfo
- EHScope
- Kind
- CommonBitFields
- CatchBitFields
- CleanupBitFields
- FilterBitFields
- EHScope
- getKind
- getCachedLandingPad
- setCachedLandingPad
- getCachedEHDispatchBlock
- setCachedEHDispatchBlock
- hasEHBranches
- getEnclosingEHScope
- EHCatchScope
- Handler
- isCatchAll
- getHandlers
- getHandlers
- getSizeForNumHandlers
- EHCatchScope
- getNumHandlers
- setCatchAllHandler
- setHandler
- setHandler
- getHandler
- clearHandlerBlocks
- begin
- end
- classof
- EHCleanupScope
- ExtInfo
- AuxillaryAllocas
- Add
- MarkUsed
- ~AuxillaryAllocas
- CollectUses
- getAuxillaryAllocas
- getExtInfo
- getExtInfo
- getSizeForCleanupSize
- getAllocatedSize
- EHCleanupScope
- Destroy
- AddAuxAllocas
- MarkEmitted
- ~EHCleanupScope
- isNormalCleanup
- getNormalBlock
- setNormalBlock
- isEHCleanup
- isActive
- setActive
- isLifetimeMarker
- setLifetimeMarker
- isFakeUse
- setFakeUse
- hasActiveFlag
- getActiveFlag
- setActiveFlag
- setTestFlagInNormalCleanup
- shouldTestFlagInNormalCleanup
- setTestFlagInEHCleanup
- shouldTestFlagInEHCleanup
- getFixupDepth
- getEnclosingNormalCleanup
- getCleanupSize
- getCleanupBuffer
- getCleanup
- hasBranches
- addBranchAfter
- getNumBranchAfters
- getBranchAfterBlock
- getBranchAfterIndex
- addBranchThrough
- hasBranchThroughs
- classof
- EHFilterScope
- getFilters
- getFilters
- EHFilterScope
- getSizeForNumFilters
- getNumFilters
- setFilter
- getFilter
- classof
- EHTerminateScope
- EHTerminateScope
- getSize
- classof
- iterator
- iterator
- iterator
- get
- operator->
- operator*
- operator++
- next
- operator++
- encloses
- strictlyEncloses
- operator==
- operator!=
- begin
- end
- popCatch
- popTerminate
- find
- stabilize
- EHPersonality
- usesFuncletPads
- isMSVCPersonality
- isWasmPersonality
Improve your Profiling and Debugging skills
Find out more