1 //===- ARCInstKind.cpp - ObjC ARC Optimization ----------------------------===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 /// This file defines several utility functions used by various ARC
11 /// optimizations which are IMHO too big to be in a header file.
13 /// WARNING: This file knows about certain library functions. It recognizes them
14 /// by name, and hardwires knowledge of their semantics.
16 /// WARNING: This file knows about how certain Objective-C library functions are
17 /// used. Naive LLVM IR transformations which would otherwise be
18 /// behavior-preserving may break these assumptions.
20 //===----------------------------------------------------------------------===//
22 #include "llvm/Analysis/ObjCARCInstKind.h"
23 #include "llvm/ADT/StringSwitch.h"
24 #include "llvm/Analysis/ObjCARCAnalysisUtils.h"
25 #include "llvm/IR/Intrinsics.h"
28 using namespace llvm::objcarc;
30 raw_ostream &llvm::objcarc::operator<<(raw_ostream &OS,
31 const ARCInstKind Class) {
33 case ARCInstKind::Retain:
34 return OS << "ARCInstKind::Retain";
35 case ARCInstKind::RetainRV:
36 return OS << "ARCInstKind::RetainRV";
37 case ARCInstKind::ClaimRV:
38 return OS << "ARCInstKind::ClaimRV";
39 case ARCInstKind::RetainBlock:
40 return OS << "ARCInstKind::RetainBlock";
41 case ARCInstKind::Release:
42 return OS << "ARCInstKind::Release";
43 case ARCInstKind::Autorelease:
44 return OS << "ARCInstKind::Autorelease";
45 case ARCInstKind::AutoreleaseRV:
46 return OS << "ARCInstKind::AutoreleaseRV";
47 case ARCInstKind::AutoreleasepoolPush:
48 return OS << "ARCInstKind::AutoreleasepoolPush";
49 case ARCInstKind::AutoreleasepoolPop:
50 return OS << "ARCInstKind::AutoreleasepoolPop";
51 case ARCInstKind::NoopCast:
52 return OS << "ARCInstKind::NoopCast";
53 case ARCInstKind::FusedRetainAutorelease:
54 return OS << "ARCInstKind::FusedRetainAutorelease";
55 case ARCInstKind::FusedRetainAutoreleaseRV:
56 return OS << "ARCInstKind::FusedRetainAutoreleaseRV";
57 case ARCInstKind::LoadWeakRetained:
58 return OS << "ARCInstKind::LoadWeakRetained";
59 case ARCInstKind::StoreWeak:
60 return OS << "ARCInstKind::StoreWeak";
61 case ARCInstKind::InitWeak:
62 return OS << "ARCInstKind::InitWeak";
63 case ARCInstKind::LoadWeak:
64 return OS << "ARCInstKind::LoadWeak";
65 case ARCInstKind::MoveWeak:
66 return OS << "ARCInstKind::MoveWeak";
67 case ARCInstKind::CopyWeak:
68 return OS << "ARCInstKind::CopyWeak";
69 case ARCInstKind::DestroyWeak:
70 return OS << "ARCInstKind::DestroyWeak";
71 case ARCInstKind::StoreStrong:
72 return OS << "ARCInstKind::StoreStrong";
73 case ARCInstKind::CallOrUser:
74 return OS << "ARCInstKind::CallOrUser";
75 case ARCInstKind::Call:
76 return OS << "ARCInstKind::Call";
77 case ARCInstKind::User:
78 return OS << "ARCInstKind::User";
79 case ARCInstKind::IntrinsicUser:
80 return OS << "ARCInstKind::IntrinsicUser";
81 case ARCInstKind::None:
82 return OS << "ARCInstKind::None";
84 llvm_unreachable("Unknown instruction class!");
87 ARCInstKind llvm::objcarc::GetFunctionClass(const Function *F) {
89 Intrinsic::ID ID = F->getIntrinsicID();
92 return ARCInstKind::CallOrUser;
93 case Intrinsic::objc_autorelease:
94 return ARCInstKind::Autorelease;
95 case Intrinsic::objc_autoreleasePoolPop:
96 return ARCInstKind::AutoreleasepoolPop;
97 case Intrinsic::objc_autoreleasePoolPush:
98 return ARCInstKind::AutoreleasepoolPush;
99 case Intrinsic::objc_autoreleaseReturnValue:
100 return ARCInstKind::AutoreleaseRV;
101 case Intrinsic::objc_copyWeak:
102 return ARCInstKind::CopyWeak;
103 case Intrinsic::objc_destroyWeak:
104 return ARCInstKind::DestroyWeak;
105 case Intrinsic::objc_initWeak:
106 return ARCInstKind::InitWeak;
107 case Intrinsic::objc_loadWeak:
108 return ARCInstKind::LoadWeak;
109 case Intrinsic::objc_loadWeakRetained:
110 return ARCInstKind::LoadWeakRetained;
111 case Intrinsic::objc_moveWeak:
112 return ARCInstKind::MoveWeak;
113 case Intrinsic::objc_release:
114 return ARCInstKind::Release;
115 case Intrinsic::objc_retain:
116 return ARCInstKind::Retain;
117 case Intrinsic::objc_retainAutorelease:
118 return ARCInstKind::FusedRetainAutorelease;
119 case Intrinsic::objc_retainAutoreleaseReturnValue:
120 return ARCInstKind::FusedRetainAutoreleaseRV;
121 case Intrinsic::objc_retainAutoreleasedReturnValue:
122 return ARCInstKind::RetainRV;
123 case Intrinsic::objc_retainBlock:
124 return ARCInstKind::RetainBlock;
125 case Intrinsic::objc_storeStrong:
126 return ARCInstKind::StoreStrong;
127 case Intrinsic::objc_storeWeak:
128 return ARCInstKind::StoreWeak;
129 case Intrinsic::objc_clang_arc_use:
130 return ARCInstKind::IntrinsicUser;
131 case Intrinsic::objc_unsafeClaimAutoreleasedReturnValue:
132 return ARCInstKind::ClaimRV;
133 case Intrinsic::objc_retainedObject:
134 return ARCInstKind::NoopCast;
135 case Intrinsic::objc_unretainedObject:
136 return ARCInstKind::NoopCast;
137 case Intrinsic::objc_unretainedPointer:
138 return ARCInstKind::NoopCast;
139 case Intrinsic::objc_retain_autorelease:
140 return ARCInstKind::FusedRetainAutorelease;
141 case Intrinsic::objc_sync_enter:
142 return ARCInstKind::User;
143 case Intrinsic::objc_sync_exit:
144 return ARCInstKind::User;
145 case Intrinsic::objc_arc_annotation_topdown_bbstart:
146 case Intrinsic::objc_arc_annotation_topdown_bbend:
147 case Intrinsic::objc_arc_annotation_bottomup_bbstart:
148 case Intrinsic::objc_arc_annotation_bottomup_bbend:
149 // Ignore annotation calls. This is important to stop the
150 // optimizer from treating annotations as uses which would
151 // make the state of the pointers they are attempting to
152 // elucidate to be incorrect.
153 return ARCInstKind::None;
157 // A whitelist of intrinsics that we know do not use objc pointers or decrement
159 static bool isInertIntrinsic(unsigned ID) {
160 // TODO: Make this into a covered switch.
162 case Intrinsic::returnaddress:
163 case Intrinsic::addressofreturnaddress:
164 case Intrinsic::frameaddress:
165 case Intrinsic::stacksave:
166 case Intrinsic::stackrestore:
167 case Intrinsic::vastart:
168 case Intrinsic::vacopy:
169 case Intrinsic::vaend:
170 case Intrinsic::objectsize:
171 case Intrinsic::prefetch:
172 case Intrinsic::stackprotector:
173 case Intrinsic::eh_return_i32:
174 case Intrinsic::eh_return_i64:
175 case Intrinsic::eh_typeid_for:
176 case Intrinsic::eh_dwarf_cfa:
177 case Intrinsic::eh_sjlj_lsda:
178 case Intrinsic::eh_sjlj_functioncontext:
179 case Intrinsic::init_trampoline:
180 case Intrinsic::adjust_trampoline:
181 case Intrinsic::lifetime_start:
182 case Intrinsic::lifetime_end:
183 case Intrinsic::invariant_start:
184 case Intrinsic::invariant_end:
185 // Don't let dbg info affect our results.
186 case Intrinsic::dbg_declare:
187 case Intrinsic::dbg_value:
188 case Intrinsic::dbg_label:
189 // Short cut: Some intrinsics obviously don't use ObjC pointers.
196 // A whitelist of intrinsics that we know do not use objc pointers or decrement
198 static bool isUseOnlyIntrinsic(unsigned ID) {
199 // We are conservative and even though intrinsics are unlikely to touch
200 // reference counts, we white list them for safety.
202 // TODO: Expand this into a covered switch. There is a lot more here.
204 case Intrinsic::memcpy:
205 case Intrinsic::memmove:
206 case Intrinsic::memset:
213 /// Determine what kind of construct V is.
214 ARCInstKind llvm::objcarc::GetARCInstKind(const Value *V) {
215 if (const Instruction *I = dyn_cast<Instruction>(V)) {
216 // Any instruction other than bitcast and gep with a pointer operand have a
217 // use of an objc pointer. Bitcasts, GEPs, Selects, PHIs transfer a pointer
218 // to a subsequent use, rather than using it themselves, in this sense.
219 // As a short cut, several other opcodes are known to have no pointer
220 // operands of interest. And ret is never followed by a release, so it's
221 // not interesting to examine.
222 switch (I->getOpcode()) {
223 case Instruction::Call: {
224 const CallInst *CI = cast<CallInst>(I);
225 // See if we have a function that we know something about.
226 if (const Function *F = CI->getCalledFunction()) {
227 ARCInstKind Class = GetFunctionClass(F);
228 if (Class != ARCInstKind::CallOrUser)
230 Intrinsic::ID ID = F->getIntrinsicID();
231 if (isInertIntrinsic(ID))
232 return ARCInstKind::None;
233 if (isUseOnlyIntrinsic(ID))
234 return ARCInstKind::User;
237 // Otherwise, be conservative.
238 return GetCallSiteClass(CI);
240 case Instruction::Invoke:
241 // Otherwise, be conservative.
242 return GetCallSiteClass(cast<InvokeInst>(I));
243 case Instruction::BitCast:
244 case Instruction::GetElementPtr:
245 case Instruction::Select:
246 case Instruction::PHI:
247 case Instruction::Ret:
248 case Instruction::Br:
249 case Instruction::Switch:
250 case Instruction::IndirectBr:
251 case Instruction::Alloca:
252 case Instruction::VAArg:
253 case Instruction::Add:
254 case Instruction::FAdd:
255 case Instruction::Sub:
256 case Instruction::FSub:
257 case Instruction::Mul:
258 case Instruction::FMul:
259 case Instruction::SDiv:
260 case Instruction::UDiv:
261 case Instruction::FDiv:
262 case Instruction::SRem:
263 case Instruction::URem:
264 case Instruction::FRem:
265 case Instruction::Shl:
266 case Instruction::LShr:
267 case Instruction::AShr:
268 case Instruction::And:
269 case Instruction::Or:
270 case Instruction::Xor:
271 case Instruction::SExt:
272 case Instruction::ZExt:
273 case Instruction::Trunc:
274 case Instruction::IntToPtr:
275 case Instruction::FCmp:
276 case Instruction::FPTrunc:
277 case Instruction::FPExt:
278 case Instruction::FPToUI:
279 case Instruction::FPToSI:
280 case Instruction::UIToFP:
281 case Instruction::SIToFP:
282 case Instruction::InsertElement:
283 case Instruction::ExtractElement:
284 case Instruction::ShuffleVector:
285 case Instruction::ExtractValue:
287 case Instruction::ICmp:
288 // Comparing a pointer with null, or any other constant, isn't an
289 // interesting use, because we don't care what the pointer points to, or
290 // about the values of any other dynamic reference-counted pointers.
291 if (IsPotentialRetainableObjPtr(I->getOperand(1)))
292 return ARCInstKind::User;
295 // For anything else, check all the operands.
296 // Note that this includes both operands of a Store: while the first
297 // operand isn't actually being dereferenced, it is being stored to
298 // memory where we can no longer track who might read it and dereference
299 // it, so we have to consider it potentially used.
300 for (User::const_op_iterator OI = I->op_begin(), OE = I->op_end();
302 if (IsPotentialRetainableObjPtr(*OI))
303 return ARCInstKind::User;
307 // Otherwise, it's totally inert for ARC purposes.
308 return ARCInstKind::None;
311 /// Test if the given class is a kind of user.
312 bool llvm::objcarc::IsUser(ARCInstKind Class) {
314 case ARCInstKind::User:
315 case ARCInstKind::CallOrUser:
316 case ARCInstKind::IntrinsicUser:
318 case ARCInstKind::Retain:
319 case ARCInstKind::RetainRV:
320 case ARCInstKind::RetainBlock:
321 case ARCInstKind::Release:
322 case ARCInstKind::Autorelease:
323 case ARCInstKind::AutoreleaseRV:
324 case ARCInstKind::AutoreleasepoolPush:
325 case ARCInstKind::AutoreleasepoolPop:
326 case ARCInstKind::NoopCast:
327 case ARCInstKind::FusedRetainAutorelease:
328 case ARCInstKind::FusedRetainAutoreleaseRV:
329 case ARCInstKind::LoadWeakRetained:
330 case ARCInstKind::StoreWeak:
331 case ARCInstKind::InitWeak:
332 case ARCInstKind::LoadWeak:
333 case ARCInstKind::MoveWeak:
334 case ARCInstKind::CopyWeak:
335 case ARCInstKind::DestroyWeak:
336 case ARCInstKind::StoreStrong:
337 case ARCInstKind::Call:
338 case ARCInstKind::None:
339 case ARCInstKind::ClaimRV:
342 llvm_unreachable("covered switch isn't covered?");
345 /// Test if the given class is objc_retain or equivalent.
346 bool llvm::objcarc::IsRetain(ARCInstKind Class) {
348 case ARCInstKind::Retain:
349 case ARCInstKind::RetainRV:
351 // I believe we treat retain block as not a retain since it can copy its
353 case ARCInstKind::RetainBlock:
354 case ARCInstKind::Release:
355 case ARCInstKind::Autorelease:
356 case ARCInstKind::AutoreleaseRV:
357 case ARCInstKind::AutoreleasepoolPush:
358 case ARCInstKind::AutoreleasepoolPop:
359 case ARCInstKind::NoopCast:
360 case ARCInstKind::FusedRetainAutorelease:
361 case ARCInstKind::FusedRetainAutoreleaseRV:
362 case ARCInstKind::LoadWeakRetained:
363 case ARCInstKind::StoreWeak:
364 case ARCInstKind::InitWeak:
365 case ARCInstKind::LoadWeak:
366 case ARCInstKind::MoveWeak:
367 case ARCInstKind::CopyWeak:
368 case ARCInstKind::DestroyWeak:
369 case ARCInstKind::StoreStrong:
370 case ARCInstKind::IntrinsicUser:
371 case ARCInstKind::CallOrUser:
372 case ARCInstKind::Call:
373 case ARCInstKind::User:
374 case ARCInstKind::None:
375 case ARCInstKind::ClaimRV:
378 llvm_unreachable("covered switch isn't covered?");
381 /// Test if the given class is objc_autorelease or equivalent.
382 bool llvm::objcarc::IsAutorelease(ARCInstKind Class) {
384 case ARCInstKind::Autorelease:
385 case ARCInstKind::AutoreleaseRV:
387 case ARCInstKind::Retain:
388 case ARCInstKind::RetainRV:
389 case ARCInstKind::ClaimRV:
390 case ARCInstKind::RetainBlock:
391 case ARCInstKind::Release:
392 case ARCInstKind::AutoreleasepoolPush:
393 case ARCInstKind::AutoreleasepoolPop:
394 case ARCInstKind::NoopCast:
395 case ARCInstKind::FusedRetainAutorelease:
396 case ARCInstKind::FusedRetainAutoreleaseRV:
397 case ARCInstKind::LoadWeakRetained:
398 case ARCInstKind::StoreWeak:
399 case ARCInstKind::InitWeak:
400 case ARCInstKind::LoadWeak:
401 case ARCInstKind::MoveWeak:
402 case ARCInstKind::CopyWeak:
403 case ARCInstKind::DestroyWeak:
404 case ARCInstKind::StoreStrong:
405 case ARCInstKind::IntrinsicUser:
406 case ARCInstKind::CallOrUser:
407 case ARCInstKind::Call:
408 case ARCInstKind::User:
409 case ARCInstKind::None:
412 llvm_unreachable("covered switch isn't covered?");
415 /// Test if the given class represents instructions which return their
416 /// argument verbatim.
417 bool llvm::objcarc::IsForwarding(ARCInstKind Class) {
419 case ARCInstKind::Retain:
420 case ARCInstKind::RetainRV:
421 case ARCInstKind::ClaimRV:
422 case ARCInstKind::Autorelease:
423 case ARCInstKind::AutoreleaseRV:
424 case ARCInstKind::NoopCast:
426 case ARCInstKind::RetainBlock:
427 case ARCInstKind::Release:
428 case ARCInstKind::AutoreleasepoolPush:
429 case ARCInstKind::AutoreleasepoolPop:
430 case ARCInstKind::FusedRetainAutorelease:
431 case ARCInstKind::FusedRetainAutoreleaseRV:
432 case ARCInstKind::LoadWeakRetained:
433 case ARCInstKind::StoreWeak:
434 case ARCInstKind::InitWeak:
435 case ARCInstKind::LoadWeak:
436 case ARCInstKind::MoveWeak:
437 case ARCInstKind::CopyWeak:
438 case ARCInstKind::DestroyWeak:
439 case ARCInstKind::StoreStrong:
440 case ARCInstKind::IntrinsicUser:
441 case ARCInstKind::CallOrUser:
442 case ARCInstKind::Call:
443 case ARCInstKind::User:
444 case ARCInstKind::None:
447 llvm_unreachable("covered switch isn't covered?");
450 /// Test if the given class represents instructions which do nothing if
451 /// passed a null pointer.
452 bool llvm::objcarc::IsNoopOnNull(ARCInstKind Class) {
454 case ARCInstKind::Retain:
455 case ARCInstKind::RetainRV:
456 case ARCInstKind::ClaimRV:
457 case ARCInstKind::Release:
458 case ARCInstKind::Autorelease:
459 case ARCInstKind::AutoreleaseRV:
460 case ARCInstKind::RetainBlock:
462 case ARCInstKind::AutoreleasepoolPush:
463 case ARCInstKind::AutoreleasepoolPop:
464 case ARCInstKind::FusedRetainAutorelease:
465 case ARCInstKind::FusedRetainAutoreleaseRV:
466 case ARCInstKind::LoadWeakRetained:
467 case ARCInstKind::StoreWeak:
468 case ARCInstKind::InitWeak:
469 case ARCInstKind::LoadWeak:
470 case ARCInstKind::MoveWeak:
471 case ARCInstKind::CopyWeak:
472 case ARCInstKind::DestroyWeak:
473 case ARCInstKind::StoreStrong:
474 case ARCInstKind::IntrinsicUser:
475 case ARCInstKind::CallOrUser:
476 case ARCInstKind::Call:
477 case ARCInstKind::User:
478 case ARCInstKind::None:
479 case ARCInstKind::NoopCast:
482 llvm_unreachable("covered switch isn't covered?");
485 /// Test if the given class represents instructions which are always safe
486 /// to mark with the "tail" keyword.
487 bool llvm::objcarc::IsAlwaysTail(ARCInstKind Class) {
488 // ARCInstKind::RetainBlock may be given a stack argument.
490 case ARCInstKind::Retain:
491 case ARCInstKind::RetainRV:
492 case ARCInstKind::ClaimRV:
493 case ARCInstKind::AutoreleaseRV:
495 case ARCInstKind::Release:
496 case ARCInstKind::Autorelease:
497 case ARCInstKind::RetainBlock:
498 case ARCInstKind::AutoreleasepoolPush:
499 case ARCInstKind::AutoreleasepoolPop:
500 case ARCInstKind::FusedRetainAutorelease:
501 case ARCInstKind::FusedRetainAutoreleaseRV:
502 case ARCInstKind::LoadWeakRetained:
503 case ARCInstKind::StoreWeak:
504 case ARCInstKind::InitWeak:
505 case ARCInstKind::LoadWeak:
506 case ARCInstKind::MoveWeak:
507 case ARCInstKind::CopyWeak:
508 case ARCInstKind::DestroyWeak:
509 case ARCInstKind::StoreStrong:
510 case ARCInstKind::IntrinsicUser:
511 case ARCInstKind::CallOrUser:
512 case ARCInstKind::Call:
513 case ARCInstKind::User:
514 case ARCInstKind::None:
515 case ARCInstKind::NoopCast:
518 llvm_unreachable("covered switch isn't covered?");
521 /// Test if the given class represents instructions which are never safe
522 /// to mark with the "tail" keyword.
523 bool llvm::objcarc::IsNeverTail(ARCInstKind Class) {
524 /// It is never safe to tail call objc_autorelease since by tail calling
525 /// objc_autorelease: fast autoreleasing causing our object to be potentially
526 /// reclaimed from the autorelease pool which violates the semantics of
527 /// __autoreleasing types in ARC.
529 case ARCInstKind::Autorelease:
531 case ARCInstKind::Retain:
532 case ARCInstKind::RetainRV:
533 case ARCInstKind::ClaimRV:
534 case ARCInstKind::AutoreleaseRV:
535 case ARCInstKind::Release:
536 case ARCInstKind::RetainBlock:
537 case ARCInstKind::AutoreleasepoolPush:
538 case ARCInstKind::AutoreleasepoolPop:
539 case ARCInstKind::FusedRetainAutorelease:
540 case ARCInstKind::FusedRetainAutoreleaseRV:
541 case ARCInstKind::LoadWeakRetained:
542 case ARCInstKind::StoreWeak:
543 case ARCInstKind::InitWeak:
544 case ARCInstKind::LoadWeak:
545 case ARCInstKind::MoveWeak:
546 case ARCInstKind::CopyWeak:
547 case ARCInstKind::DestroyWeak:
548 case ARCInstKind::StoreStrong:
549 case ARCInstKind::IntrinsicUser:
550 case ARCInstKind::CallOrUser:
551 case ARCInstKind::Call:
552 case ARCInstKind::User:
553 case ARCInstKind::None:
554 case ARCInstKind::NoopCast:
557 llvm_unreachable("covered switch isn't covered?");
560 /// Test if the given class represents instructions which are always safe
561 /// to mark with the nounwind attribute.
562 bool llvm::objcarc::IsNoThrow(ARCInstKind Class) {
563 // objc_retainBlock is not nounwind because it calls user copy constructors
564 // which could theoretically throw.
566 case ARCInstKind::Retain:
567 case ARCInstKind::RetainRV:
568 case ARCInstKind::ClaimRV:
569 case ARCInstKind::Release:
570 case ARCInstKind::Autorelease:
571 case ARCInstKind::AutoreleaseRV:
572 case ARCInstKind::AutoreleasepoolPush:
573 case ARCInstKind::AutoreleasepoolPop:
575 case ARCInstKind::RetainBlock:
576 case ARCInstKind::FusedRetainAutorelease:
577 case ARCInstKind::FusedRetainAutoreleaseRV:
578 case ARCInstKind::LoadWeakRetained:
579 case ARCInstKind::StoreWeak:
580 case ARCInstKind::InitWeak:
581 case ARCInstKind::LoadWeak:
582 case ARCInstKind::MoveWeak:
583 case ARCInstKind::CopyWeak:
584 case ARCInstKind::DestroyWeak:
585 case ARCInstKind::StoreStrong:
586 case ARCInstKind::IntrinsicUser:
587 case ARCInstKind::CallOrUser:
588 case ARCInstKind::Call:
589 case ARCInstKind::User:
590 case ARCInstKind::None:
591 case ARCInstKind::NoopCast:
594 llvm_unreachable("covered switch isn't covered?");
597 /// Test whether the given instruction can autorelease any pointer or cause an
598 /// autoreleasepool pop.
600 /// This means that it *could* interrupt the RV optimization.
601 bool llvm::objcarc::CanInterruptRV(ARCInstKind Class) {
603 case ARCInstKind::AutoreleasepoolPop:
604 case ARCInstKind::CallOrUser:
605 case ARCInstKind::Call:
606 case ARCInstKind::Autorelease:
607 case ARCInstKind::AutoreleaseRV:
608 case ARCInstKind::FusedRetainAutorelease:
609 case ARCInstKind::FusedRetainAutoreleaseRV:
611 case ARCInstKind::Retain:
612 case ARCInstKind::RetainRV:
613 case ARCInstKind::ClaimRV:
614 case ARCInstKind::Release:
615 case ARCInstKind::AutoreleasepoolPush:
616 case ARCInstKind::RetainBlock:
617 case ARCInstKind::LoadWeakRetained:
618 case ARCInstKind::StoreWeak:
619 case ARCInstKind::InitWeak:
620 case ARCInstKind::LoadWeak:
621 case ARCInstKind::MoveWeak:
622 case ARCInstKind::CopyWeak:
623 case ARCInstKind::DestroyWeak:
624 case ARCInstKind::StoreStrong:
625 case ARCInstKind::IntrinsicUser:
626 case ARCInstKind::User:
627 case ARCInstKind::None:
628 case ARCInstKind::NoopCast:
631 llvm_unreachable("covered switch isn't covered?");
634 bool llvm::objcarc::CanDecrementRefCount(ARCInstKind Kind) {
636 case ARCInstKind::Retain:
637 case ARCInstKind::RetainRV:
638 case ARCInstKind::Autorelease:
639 case ARCInstKind::AutoreleaseRV:
640 case ARCInstKind::NoopCast:
641 case ARCInstKind::FusedRetainAutorelease:
642 case ARCInstKind::FusedRetainAutoreleaseRV:
643 case ARCInstKind::IntrinsicUser:
644 case ARCInstKind::User:
645 case ARCInstKind::None:
648 // The cases below are conservative.
650 // RetainBlock can result in user defined copy constructors being called
651 // implying releases may occur.
652 case ARCInstKind::RetainBlock:
653 case ARCInstKind::Release:
654 case ARCInstKind::AutoreleasepoolPush:
655 case ARCInstKind::AutoreleasepoolPop:
656 case ARCInstKind::LoadWeakRetained:
657 case ARCInstKind::StoreWeak:
658 case ARCInstKind::InitWeak:
659 case ARCInstKind::LoadWeak:
660 case ARCInstKind::MoveWeak:
661 case ARCInstKind::CopyWeak:
662 case ARCInstKind::DestroyWeak:
663 case ARCInstKind::StoreStrong:
664 case ARCInstKind::CallOrUser:
665 case ARCInstKind::Call:
666 case ARCInstKind::ClaimRV:
670 llvm_unreachable("covered switch isn't covered?");