1 //===--- CGCleanup.cpp - Bookkeeping and code emission for cleanups -------===// 2 // 3 // The LLVM Compiler Infrastructure 4 // 5 // This file is distributed under the University of Illinois Open Source 6 // License. See LICENSE.TXT for details. 7 // 8 //===----------------------------------------------------------------------===// 9 // 10 // This file contains code dealing with the IR generation for cleanups 11 // and related information. 12 // 13 // A "cleanup" is a piece of code which needs to be executed whenever 14 // control transfers out of a particular scope. This can be 15 // conditionalized to occur only on exceptional control flow, only on 16 // normal control flow, or both. 17 // 18 //===----------------------------------------------------------------------===// 19 20 #include "CGCleanup.h" 21 #include "CodeGenFunction.h" 22 23 using namespace clang; 24 using namespace CodeGen; 25 26 bool DominatingValue<RValue>::saved_type::needsSaving(RValue rv) { 27 if (rv.isScalar()) 28 return DominatingLLVMValue::needsSaving(rv.getScalarVal()); 29 if (rv.isAggregate()) 30 return DominatingLLVMValue::needsSaving(rv.getAggregateAddr()); 31 return true; 32 } 33 34 DominatingValue<RValue>::saved_type 35 DominatingValue<RValue>::saved_type::save(CodeGenFunction &CGF, RValue rv) { 36 if (rv.isScalar()) { 37 llvm::Value *V = rv.getScalarVal(); 38 39 // These automatically dominate and don't need to be saved. 40 if (!DominatingLLVMValue::needsSaving(V)) 41 return saved_type(V, ScalarLiteral); 42 43 // Everything else needs an alloca. 44 llvm::Value *addr = CGF.CreateTempAlloca(V->getType(), "saved-rvalue"); 45 CGF.Builder.CreateStore(V, addr); 46 return saved_type(addr, ScalarAddress); 47 } 48 49 if (rv.isComplex()) { 50 CodeGenFunction::ComplexPairTy V = rv.getComplexVal(); 51 llvm::Type *ComplexTy = 52 llvm::StructType::get(V.first->getType(), V.second->getType(), 53 (void*) nullptr); 54 llvm::Value *addr = CGF.CreateTempAlloca(ComplexTy, "saved-complex"); 55 CGF.Builder.CreateStore(V.first, CGF.Builder.CreateStructGEP(addr, 0)); 56 CGF.Builder.CreateStore(V.second, CGF.Builder.CreateStructGEP(addr, 1)); 57 return saved_type(addr, ComplexAddress); 58 } 59 60 assert(rv.isAggregate()); 61 llvm::Value *V = rv.getAggregateAddr(); // TODO: volatile? 62 if (!DominatingLLVMValue::needsSaving(V)) 63 return saved_type(V, AggregateLiteral); 64 65 llvm::Value *addr = CGF.CreateTempAlloca(V->getType(), "saved-rvalue"); 66 CGF.Builder.CreateStore(V, addr); 67 return saved_type(addr, AggregateAddress); 68 } 69 70 /// Given a saved r-value produced by SaveRValue, perform the code 71 /// necessary to restore it to usability at the current insertion 72 /// point. 73 RValue DominatingValue<RValue>::saved_type::restore(CodeGenFunction &CGF) { 74 switch (K) { 75 case ScalarLiteral: 76 return RValue::get(Value); 77 case ScalarAddress: 78 return RValue::get(CGF.Builder.CreateLoad(Value)); 79 case AggregateLiteral: 80 return RValue::getAggregate(Value); 81 case AggregateAddress: 82 return RValue::getAggregate(CGF.Builder.CreateLoad(Value)); 83 case ComplexAddress: { 84 llvm::Value *real = 85 CGF.Builder.CreateLoad(CGF.Builder.CreateStructGEP(Value, 0)); 86 llvm::Value *imag = 87 CGF.Builder.CreateLoad(CGF.Builder.CreateStructGEP(Value, 1)); 88 return RValue::getComplex(real, imag); 89 } 90 } 91 92 llvm_unreachable("bad saved r-value kind"); 93 } 94 95 /// Push an entry of the given size onto this protected-scope stack. 96 char *EHScopeStack::allocate(size_t Size) { 97 if (!StartOfBuffer) { 98 unsigned Capacity = 1024; 99 while (Capacity < Size) Capacity *= 2; 100 StartOfBuffer = new char[Capacity]; 101 StartOfData = EndOfBuffer = StartOfBuffer + Capacity; 102 } else if (static_cast<size_t>(StartOfData - StartOfBuffer) < Size) { 103 unsigned CurrentCapacity = EndOfBuffer - StartOfBuffer; 104 unsigned UsedCapacity = CurrentCapacity - (StartOfData - StartOfBuffer); 105 106 unsigned NewCapacity = CurrentCapacity; 107 do { 108 NewCapacity *= 2; 109 } while (NewCapacity < UsedCapacity + Size); 110 111 char *NewStartOfBuffer = new char[NewCapacity]; 112 char *NewEndOfBuffer = NewStartOfBuffer + NewCapacity; 113 char *NewStartOfData = NewEndOfBuffer - UsedCapacity; 114 memcpy(NewStartOfData, StartOfData, UsedCapacity); 115 delete [] StartOfBuffer; 116 StartOfBuffer = NewStartOfBuffer; 117 EndOfBuffer = NewEndOfBuffer; 118 StartOfData = NewStartOfData; 119 } 120 121 assert(StartOfBuffer + Size <= StartOfData); 122 StartOfData -= Size; 123 return StartOfData; 124 } 125 126 EHScopeStack::stable_iterator 127 EHScopeStack::getInnermostActiveNormalCleanup() const { 128 for (stable_iterator si = getInnermostNormalCleanup(), se = stable_end(); 129 si != se; ) { 130 EHCleanupScope &cleanup = cast<EHCleanupScope>(*find(si)); 131 if (cleanup.isActive()) return si; 132 si = cleanup.getEnclosingNormalCleanup(); 133 } 134 return stable_end(); 135 } 136 137 EHScopeStack::stable_iterator EHScopeStack::getInnermostActiveEHScope() const { 138 for (stable_iterator si = getInnermostEHScope(), se = stable_end(); 139 si != se; ) { 140 // Skip over inactive cleanups. 141 EHCleanupScope *cleanup = dyn_cast<EHCleanupScope>(&*find(si)); 142 if (cleanup && !cleanup->isActive()) { 143 si = cleanup->getEnclosingEHScope(); 144 continue; 145 } 146 147 // All other scopes are always active. 148 return si; 149 } 150 151 return stable_end(); 152 } 153 154 155 void *EHScopeStack::pushCleanup(CleanupKind Kind, size_t Size) { 156 assert(((Size % sizeof(void*)) == 0) && "cleanup type is misaligned"); 157 char *Buffer = allocate(EHCleanupScope::getSizeForCleanupSize(Size)); 158 bool IsNormalCleanup = Kind & NormalCleanup; 159 bool IsEHCleanup = Kind & EHCleanup; 160 bool IsActive = !(Kind & InactiveCleanup); 161 EHCleanupScope *Scope = 162 new (Buffer) EHCleanupScope(IsNormalCleanup, 163 IsEHCleanup, 164 IsActive, 165 Size, 166 BranchFixups.size(), 167 InnermostNormalCleanup, 168 InnermostEHScope); 169 if (IsNormalCleanup) 170 InnermostNormalCleanup = stable_begin(); 171 if (IsEHCleanup) 172 InnermostEHScope = stable_begin(); 173 174 return Scope->getCleanupBuffer(); 175 } 176 177 void EHScopeStack::popCleanup() { 178 assert(!empty() && "popping exception stack when not empty"); 179 180 assert(isa<EHCleanupScope>(*begin())); 181 EHCleanupScope &Cleanup = cast<EHCleanupScope>(*begin()); 182 InnermostNormalCleanup = Cleanup.getEnclosingNormalCleanup(); 183 InnermostEHScope = Cleanup.getEnclosingEHScope(); 184 StartOfData += Cleanup.getAllocatedSize(); 185 186 // Destroy the cleanup. 187 Cleanup.~EHCleanupScope(); 188 189 // Check whether we can shrink the branch-fixups stack. 190 if (!BranchFixups.empty()) { 191 // If we no longer have any normal cleanups, all the fixups are 192 // complete. 193 if (!hasNormalCleanups()) 194 BranchFixups.clear(); 195 196 // Otherwise we can still trim out unnecessary nulls. 197 else 198 popNullFixups(); 199 } 200 } 201 202 EHFilterScope *EHScopeStack::pushFilter(unsigned numFilters) { 203 assert(getInnermostEHScope() == stable_end()); 204 char *buffer = allocate(EHFilterScope::getSizeForNumFilters(numFilters)); 205 EHFilterScope *filter = new (buffer) EHFilterScope(numFilters); 206 InnermostEHScope = stable_begin(); 207 return filter; 208 } 209 210 void EHScopeStack::popFilter() { 211 assert(!empty() && "popping exception stack when not empty"); 212 213 EHFilterScope &filter = cast<EHFilterScope>(*begin()); 214 StartOfData += EHFilterScope::getSizeForNumFilters(filter.getNumFilters()); 215 216 InnermostEHScope = filter.getEnclosingEHScope(); 217 } 218 219 EHCatchScope *EHScopeStack::pushCatch(unsigned numHandlers) { 220 char *buffer = allocate(EHCatchScope::getSizeForNumHandlers(numHandlers)); 221 EHCatchScope *scope = 222 new (buffer) EHCatchScope(numHandlers, InnermostEHScope); 223 InnermostEHScope = stable_begin(); 224 return scope; 225 } 226 227 void EHScopeStack::pushTerminate() { 228 char *Buffer = allocate(EHTerminateScope::getSize()); 229 new (Buffer) EHTerminateScope(InnermostEHScope); 230 InnermostEHScope = stable_begin(); 231 } 232 233 /// Remove any 'null' fixups on the stack. However, we can't pop more 234 /// fixups than the fixup depth on the innermost normal cleanup, or 235 /// else fixups that we try to add to that cleanup will end up in the 236 /// wrong place. We *could* try to shrink fixup depths, but that's 237 /// actually a lot of work for little benefit. 238 void EHScopeStack::popNullFixups() { 239 // We expect this to only be called when there's still an innermost 240 // normal cleanup; otherwise there really shouldn't be any fixups. 241 assert(hasNormalCleanups()); 242 243 EHScopeStack::iterator it = find(InnermostNormalCleanup); 244 unsigned MinSize = cast<EHCleanupScope>(*it).getFixupDepth(); 245 assert(BranchFixups.size() >= MinSize && "fixup stack out of order"); 246 247 while (BranchFixups.size() > MinSize && 248 BranchFixups.back().Destination == nullptr) 249 BranchFixups.pop_back(); 250 } 251 252 void CodeGenFunction::initFullExprCleanup() { 253 // Create a variable to decide whether the cleanup needs to be run. 254 llvm::AllocaInst *active 255 = CreateTempAlloca(Builder.getInt1Ty(), "cleanup.cond"); 256 257 // Initialize it to false at a site that's guaranteed to be run 258 // before each evaluation. 259 setBeforeOutermostConditional(Builder.getFalse(), active); 260 261 // Initialize it to true at the current location. 262 Builder.CreateStore(Builder.getTrue(), active); 263 264 // Set that as the active flag in the cleanup. 265 EHCleanupScope &cleanup = cast<EHCleanupScope>(*EHStack.begin()); 266 assert(!cleanup.getActiveFlag() && "cleanup already has active flag?"); 267 cleanup.setActiveFlag(active); 268 269 if (cleanup.isNormalCleanup()) cleanup.setTestFlagInNormalCleanup(); 270 if (cleanup.isEHCleanup()) cleanup.setTestFlagInEHCleanup(); 271 } 272 273 void EHScopeStack::Cleanup::anchor() {} 274 275 /// All the branch fixups on the EH stack have propagated out past the 276 /// outermost normal cleanup; resolve them all by adding cases to the 277 /// given switch instruction. 278 static void ResolveAllBranchFixups(CodeGenFunction &CGF, 279 llvm::SwitchInst *Switch, 280 llvm::BasicBlock *CleanupEntry) { 281 llvm::SmallPtrSet<llvm::BasicBlock*, 4> CasesAdded; 282 283 for (unsigned I = 0, E = CGF.EHStack.getNumBranchFixups(); I != E; ++I) { 284 // Skip this fixup if its destination isn't set. 285 BranchFixup &Fixup = CGF.EHStack.getBranchFixup(I); 286 if (Fixup.Destination == nullptr) continue; 287 288 // If there isn't an OptimisticBranchBlock, then InitialBranch is 289 // still pointing directly to its destination; forward it to the 290 // appropriate cleanup entry. This is required in the specific 291 // case of 292 // { std::string s; goto lbl; } 293 // lbl: 294 // i.e. where there's an unresolved fixup inside a single cleanup 295 // entry which we're currently popping. 296 if (Fixup.OptimisticBranchBlock == nullptr) { 297 new llvm::StoreInst(CGF.Builder.getInt32(Fixup.DestinationIndex), 298 CGF.getNormalCleanupDestSlot(), 299 Fixup.InitialBranch); 300 Fixup.InitialBranch->setSuccessor(0, CleanupEntry); 301 } 302 303 // Don't add this case to the switch statement twice. 304 if (!CasesAdded.insert(Fixup.Destination)) continue; 305 306 Switch->addCase(CGF.Builder.getInt32(Fixup.DestinationIndex), 307 Fixup.Destination); 308 } 309 310 CGF.EHStack.clearFixups(); 311 } 312 313 /// Transitions the terminator of the given exit-block of a cleanup to 314 /// be a cleanup switch. 315 static llvm::SwitchInst *TransitionToCleanupSwitch(CodeGenFunction &CGF, 316 llvm::BasicBlock *Block) { 317 // If it's a branch, turn it into a switch whose default 318 // destination is its original target. 319 llvm::TerminatorInst *Term = Block->getTerminator(); 320 assert(Term && "can't transition block without terminator"); 321 322 if (llvm::BranchInst *Br = dyn_cast<llvm::BranchInst>(Term)) { 323 assert(Br->isUnconditional()); 324 llvm::LoadInst *Load = 325 new llvm::LoadInst(CGF.getNormalCleanupDestSlot(), "cleanup.dest", Term); 326 llvm::SwitchInst *Switch = 327 llvm::SwitchInst::Create(Load, Br->getSuccessor(0), 4, Block); 328 Br->eraseFromParent(); 329 return Switch; 330 } else { 331 return cast<llvm::SwitchInst>(Term); 332 } 333 } 334 335 void CodeGenFunction::ResolveBranchFixups(llvm::BasicBlock *Block) { 336 assert(Block && "resolving a null target block"); 337 if (!EHStack.getNumBranchFixups()) return; 338 339 assert(EHStack.hasNormalCleanups() && 340 "branch fixups exist with no normal cleanups on stack"); 341 342 llvm::SmallPtrSet<llvm::BasicBlock*, 4> ModifiedOptimisticBlocks; 343 bool ResolvedAny = false; 344 345 for (unsigned I = 0, E = EHStack.getNumBranchFixups(); I != E; ++I) { 346 // Skip this fixup if its destination doesn't match. 347 BranchFixup &Fixup = EHStack.getBranchFixup(I); 348 if (Fixup.Destination != Block) continue; 349 350 Fixup.Destination = nullptr; 351 ResolvedAny = true; 352 353 // If it doesn't have an optimistic branch block, LatestBranch is 354 // already pointing to the right place. 355 llvm::BasicBlock *BranchBB = Fixup.OptimisticBranchBlock; 356 if (!BranchBB) 357 continue; 358 359 // Don't process the same optimistic branch block twice. 360 if (!ModifiedOptimisticBlocks.insert(BranchBB)) 361 continue; 362 363 llvm::SwitchInst *Switch = TransitionToCleanupSwitch(*this, BranchBB); 364 365 // Add a case to the switch. 366 Switch->addCase(Builder.getInt32(Fixup.DestinationIndex), Block); 367 } 368 369 if (ResolvedAny) 370 EHStack.popNullFixups(); 371 } 372 373 /// Pops cleanup blocks until the given savepoint is reached. 374 void CodeGenFunction::PopCleanupBlocks(EHScopeStack::stable_iterator Old) { 375 assert(Old.isValid()); 376 377 while (EHStack.stable_begin() != Old) { 378 EHCleanupScope &Scope = cast<EHCleanupScope>(*EHStack.begin()); 379 380 // As long as Old strictly encloses the scope's enclosing normal 381 // cleanup, we're going to emit another normal cleanup which 382 // fallthrough can propagate through. 383 bool FallThroughIsBranchThrough = 384 Old.strictlyEncloses(Scope.getEnclosingNormalCleanup()); 385 386 PopCleanupBlock(FallThroughIsBranchThrough); 387 } 388 } 389 390 /// Pops cleanup blocks until the given savepoint is reached, then add the 391 /// cleanups from the given savepoint in the lifetime-extended cleanups stack. 392 void 393 CodeGenFunction::PopCleanupBlocks(EHScopeStack::stable_iterator Old, 394 size_t OldLifetimeExtendedSize) { 395 PopCleanupBlocks(Old); 396 397 // Move our deferred cleanups onto the EH stack. 398 for (size_t I = OldLifetimeExtendedSize, 399 E = LifetimeExtendedCleanupStack.size(); I != E; /**/) { 400 // Alignment should be guaranteed by the vptrs in the individual cleanups. 401 assert((I % llvm::alignOf<LifetimeExtendedCleanupHeader>() == 0) && 402 "misaligned cleanup stack entry"); 403 404 LifetimeExtendedCleanupHeader &Header = 405 reinterpret_cast<LifetimeExtendedCleanupHeader&>( 406 LifetimeExtendedCleanupStack[I]); 407 I += sizeof(Header); 408 409 EHStack.pushCopyOfCleanup(Header.getKind(), 410 &LifetimeExtendedCleanupStack[I], 411 Header.getSize()); 412 I += Header.getSize(); 413 } 414 LifetimeExtendedCleanupStack.resize(OldLifetimeExtendedSize); 415 } 416 417 static llvm::BasicBlock *CreateNormalEntry(CodeGenFunction &CGF, 418 EHCleanupScope &Scope) { 419 assert(Scope.isNormalCleanup()); 420 llvm::BasicBlock *Entry = Scope.getNormalBlock(); 421 if (!Entry) { 422 Entry = CGF.createBasicBlock("cleanup"); 423 Scope.setNormalBlock(Entry); 424 } 425 return Entry; 426 } 427 428 /// Attempts to reduce a cleanup's entry block to a fallthrough. This 429 /// is basically llvm::MergeBlockIntoPredecessor, except 430 /// simplified/optimized for the tighter constraints on cleanup blocks. 431 /// 432 /// Returns the new block, whatever it is. 433 static llvm::BasicBlock *SimplifyCleanupEntry(CodeGenFunction &CGF, 434 llvm::BasicBlock *Entry) { 435 llvm::BasicBlock *Pred = Entry->getSinglePredecessor(); 436 if (!Pred) return Entry; 437 438 llvm::BranchInst *Br = dyn_cast<llvm::BranchInst>(Pred->getTerminator()); 439 if (!Br || Br->isConditional()) return Entry; 440 assert(Br->getSuccessor(0) == Entry); 441 442 // If we were previously inserting at the end of the cleanup entry 443 // block, we'll need to continue inserting at the end of the 444 // predecessor. 445 bool WasInsertBlock = CGF.Builder.GetInsertBlock() == Entry; 446 assert(!WasInsertBlock || CGF.Builder.GetInsertPoint() == Entry->end()); 447 448 // Kill the branch. 449 Br->eraseFromParent(); 450 451 // Replace all uses of the entry with the predecessor, in case there 452 // are phis in the cleanup. 453 Entry->replaceAllUsesWith(Pred); 454 455 // Merge the blocks. 456 Pred->getInstList().splice(Pred->end(), Entry->getInstList()); 457 458 // Kill the entry block. 459 Entry->eraseFromParent(); 460 461 if (WasInsertBlock) 462 CGF.Builder.SetInsertPoint(Pred); 463 464 return Pred; 465 } 466 467 static void EmitCleanup(CodeGenFunction &CGF, 468 EHScopeStack::Cleanup *Fn, 469 EHScopeStack::Cleanup::Flags flags, 470 llvm::Value *ActiveFlag) { 471 // EH cleanups always occur within a terminate scope. 472 if (flags.isForEHCleanup()) CGF.EHStack.pushTerminate(); 473 474 // If there's an active flag, load it and skip the cleanup if it's 475 // false. 476 llvm::BasicBlock *ContBB = nullptr; 477 if (ActiveFlag) { 478 ContBB = CGF.createBasicBlock("cleanup.done"); 479 llvm::BasicBlock *CleanupBB = CGF.createBasicBlock("cleanup.action"); 480 llvm::Value *IsActive 481 = CGF.Builder.CreateLoad(ActiveFlag, "cleanup.is_active"); 482 CGF.Builder.CreateCondBr(IsActive, CleanupBB, ContBB); 483 CGF.EmitBlock(CleanupBB); 484 } 485 486 // Ask the cleanup to emit itself. 487 Fn->Emit(CGF, flags); 488 assert(CGF.HaveInsertPoint() && "cleanup ended with no insertion point?"); 489 490 // Emit the continuation block if there was an active flag. 491 if (ActiveFlag) 492 CGF.EmitBlock(ContBB); 493 494 // Leave the terminate scope. 495 if (flags.isForEHCleanup()) CGF.EHStack.popTerminate(); 496 } 497 498 static void ForwardPrebranchedFallthrough(llvm::BasicBlock *Exit, 499 llvm::BasicBlock *From, 500 llvm::BasicBlock *To) { 501 // Exit is the exit block of a cleanup, so it always terminates in 502 // an unconditional branch or a switch. 503 llvm::TerminatorInst *Term = Exit->getTerminator(); 504 505 if (llvm::BranchInst *Br = dyn_cast<llvm::BranchInst>(Term)) { 506 assert(Br->isUnconditional() && Br->getSuccessor(0) == From); 507 Br->setSuccessor(0, To); 508 } else { 509 llvm::SwitchInst *Switch = cast<llvm::SwitchInst>(Term); 510 for (unsigned I = 0, E = Switch->getNumSuccessors(); I != E; ++I) 511 if (Switch->getSuccessor(I) == From) 512 Switch->setSuccessor(I, To); 513 } 514 } 515 516 /// We don't need a normal entry block for the given cleanup. 517 /// Optimistic fixup branches can cause these blocks to come into 518 /// existence anyway; if so, destroy it. 519 /// 520 /// The validity of this transformation is very much specific to the 521 /// exact ways in which we form branches to cleanup entries. 522 static void destroyOptimisticNormalEntry(CodeGenFunction &CGF, 523 EHCleanupScope &scope) { 524 llvm::BasicBlock *entry = scope.getNormalBlock(); 525 if (!entry) return; 526 527 // Replace all the uses with unreachable. 528 llvm::BasicBlock *unreachableBB = CGF.getUnreachableBlock(); 529 for (llvm::BasicBlock::use_iterator 530 i = entry->use_begin(), e = entry->use_end(); i != e; ) { 531 llvm::Use &use = *i; 532 ++i; 533 534 use.set(unreachableBB); 535 536 // The only uses should be fixup switches. 537 llvm::SwitchInst *si = cast<llvm::SwitchInst>(use.getUser()); 538 if (si->getNumCases() == 1 && si->getDefaultDest() == unreachableBB) { 539 // Replace the switch with a branch. 540 llvm::BranchInst::Create(si->case_begin().getCaseSuccessor(), si); 541 542 // The switch operand is a load from the cleanup-dest alloca. 543 llvm::LoadInst *condition = cast<llvm::LoadInst>(si->getCondition()); 544 545 // Destroy the switch. 546 si->eraseFromParent(); 547 548 // Destroy the load. 549 assert(condition->getOperand(0) == CGF.NormalCleanupDest); 550 assert(condition->use_empty()); 551 condition->eraseFromParent(); 552 } 553 } 554 555 assert(entry->use_empty()); 556 delete entry; 557 } 558 559 /// Pops a cleanup block. If the block includes a normal cleanup, the 560 /// current insertion point is threaded through the cleanup, as are 561 /// any branch fixups on the cleanup. 562 void CodeGenFunction::PopCleanupBlock(bool FallthroughIsBranchThrough) { 563 assert(!EHStack.empty() && "cleanup stack is empty!"); 564 assert(isa<EHCleanupScope>(*EHStack.begin()) && "top not a cleanup!"); 565 EHCleanupScope &Scope = cast<EHCleanupScope>(*EHStack.begin()); 566 assert(Scope.getFixupDepth() <= EHStack.getNumBranchFixups()); 567 568 // Remember activation information. 569 bool IsActive = Scope.isActive(); 570 llvm::Value *NormalActiveFlag = 571 Scope.shouldTestFlagInNormalCleanup() ? Scope.getActiveFlag() : nullptr; 572 llvm::Value *EHActiveFlag = 573 Scope.shouldTestFlagInEHCleanup() ? Scope.getActiveFlag() : nullptr; 574 575 // Check whether we need an EH cleanup. This is only true if we've 576 // generated a lazy EH cleanup block. 577 llvm::BasicBlock *EHEntry = Scope.getCachedEHDispatchBlock(); 578 assert(Scope.hasEHBranches() == (EHEntry != nullptr)); 579 bool RequiresEHCleanup = (EHEntry != nullptr); 580 EHScopeStack::stable_iterator EHParent = Scope.getEnclosingEHScope(); 581 582 // Check the three conditions which might require a normal cleanup: 583 584 // - whether there are branch fix-ups through this cleanup 585 unsigned FixupDepth = Scope.getFixupDepth(); 586 bool HasFixups = EHStack.getNumBranchFixups() != FixupDepth; 587 588 // - whether there are branch-throughs or branch-afters 589 bool HasExistingBranches = Scope.hasBranches(); 590 591 // - whether there's a fallthrough 592 llvm::BasicBlock *FallthroughSource = Builder.GetInsertBlock(); 593 bool HasFallthrough = (FallthroughSource != nullptr && IsActive); 594 595 // Branch-through fall-throughs leave the insertion point set to the 596 // end of the last cleanup, which points to the current scope. The 597 // rest of IR gen doesn't need to worry about this; it only happens 598 // during the execution of PopCleanupBlocks(). 599 bool HasPrebranchedFallthrough = 600 (FallthroughSource && FallthroughSource->getTerminator()); 601 602 // If this is a normal cleanup, then having a prebranched 603 // fallthrough implies that the fallthrough source unconditionally 604 // jumps here. 605 assert(!Scope.isNormalCleanup() || !HasPrebranchedFallthrough || 606 (Scope.getNormalBlock() && 607 FallthroughSource->getTerminator()->getSuccessor(0) 608 == Scope.getNormalBlock())); 609 610 bool RequiresNormalCleanup = false; 611 if (Scope.isNormalCleanup() && 612 (HasFixups || HasExistingBranches || HasFallthrough)) { 613 RequiresNormalCleanup = true; 614 } 615 616 // If we have a prebranched fallthrough into an inactive normal 617 // cleanup, rewrite it so that it leads to the appropriate place. 618 if (Scope.isNormalCleanup() && HasPrebranchedFallthrough && !IsActive) { 619 llvm::BasicBlock *prebranchDest; 620 621 // If the prebranch is semantically branching through the next 622 // cleanup, just forward it to the next block, leaving the 623 // insertion point in the prebranched block. 624 if (FallthroughIsBranchThrough) { 625 EHScope &enclosing = *EHStack.find(Scope.getEnclosingNormalCleanup()); 626 prebranchDest = CreateNormalEntry(*this, cast<EHCleanupScope>(enclosing)); 627 628 // Otherwise, we need to make a new block. If the normal cleanup 629 // isn't being used at all, we could actually reuse the normal 630 // entry block, but this is simpler, and it avoids conflicts with 631 // dead optimistic fixup branches. 632 } else { 633 prebranchDest = createBasicBlock("forwarded-prebranch"); 634 EmitBlock(prebranchDest); 635 } 636 637 llvm::BasicBlock *normalEntry = Scope.getNormalBlock(); 638 assert(normalEntry && !normalEntry->use_empty()); 639 640 ForwardPrebranchedFallthrough(FallthroughSource, 641 normalEntry, prebranchDest); 642 } 643 644 // If we don't need the cleanup at all, we're done. 645 if (!RequiresNormalCleanup && !RequiresEHCleanup) { 646 destroyOptimisticNormalEntry(*this, Scope); 647 EHStack.popCleanup(); // safe because there are no fixups 648 assert(EHStack.getNumBranchFixups() == 0 || 649 EHStack.hasNormalCleanups()); 650 return; 651 } 652 653 // Copy the cleanup emission data out. Note that SmallVector 654 // guarantees maximal alignment for its buffer regardless of its 655 // type parameter. 656 SmallVector<char, 8*sizeof(void*)> CleanupBuffer; 657 CleanupBuffer.reserve(Scope.getCleanupSize()); 658 memcpy(CleanupBuffer.data(), 659 Scope.getCleanupBuffer(), Scope.getCleanupSize()); 660 CleanupBuffer.set_size(Scope.getCleanupSize()); 661 EHScopeStack::Cleanup *Fn = 662 reinterpret_cast<EHScopeStack::Cleanup*>(CleanupBuffer.data()); 663 664 EHScopeStack::Cleanup::Flags cleanupFlags; 665 if (Scope.isNormalCleanup()) 666 cleanupFlags.setIsNormalCleanupKind(); 667 if (Scope.isEHCleanup()) 668 cleanupFlags.setIsEHCleanupKind(); 669 670 if (!RequiresNormalCleanup) { 671 destroyOptimisticNormalEntry(*this, Scope); 672 EHStack.popCleanup(); 673 } else { 674 // If we have a fallthrough and no other need for the cleanup, 675 // emit it directly. 676 if (HasFallthrough && !HasPrebranchedFallthrough && 677 !HasFixups && !HasExistingBranches) { 678 679 destroyOptimisticNormalEntry(*this, Scope); 680 EHStack.popCleanup(); 681 682 EmitCleanup(*this, Fn, cleanupFlags, NormalActiveFlag); 683 684 // Otherwise, the best approach is to thread everything through 685 // the cleanup block and then try to clean up after ourselves. 686 } else { 687 // Force the entry block to exist. 688 llvm::BasicBlock *NormalEntry = CreateNormalEntry(*this, Scope); 689 690 // I. Set up the fallthrough edge in. 691 692 CGBuilderTy::InsertPoint savedInactiveFallthroughIP; 693 694 // If there's a fallthrough, we need to store the cleanup 695 // destination index. For fall-throughs this is always zero. 696 if (HasFallthrough) { 697 if (!HasPrebranchedFallthrough) 698 Builder.CreateStore(Builder.getInt32(0), getNormalCleanupDestSlot()); 699 700 // Otherwise, save and clear the IP if we don't have fallthrough 701 // because the cleanup is inactive. 702 } else if (FallthroughSource) { 703 assert(!IsActive && "source without fallthrough for active cleanup"); 704 savedInactiveFallthroughIP = Builder.saveAndClearIP(); 705 } 706 707 // II. Emit the entry block. This implicitly branches to it if 708 // we have fallthrough. All the fixups and existing branches 709 // should already be branched to it. 710 EmitBlock(NormalEntry); 711 712 // III. Figure out where we're going and build the cleanup 713 // epilogue. 714 715 bool HasEnclosingCleanups = 716 (Scope.getEnclosingNormalCleanup() != EHStack.stable_end()); 717 718 // Compute the branch-through dest if we need it: 719 // - if there are branch-throughs threaded through the scope 720 // - if fall-through is a branch-through 721 // - if there are fixups that will be optimistically forwarded 722 // to the enclosing cleanup 723 llvm::BasicBlock *BranchThroughDest = nullptr; 724 if (Scope.hasBranchThroughs() || 725 (FallthroughSource && FallthroughIsBranchThrough) || 726 (HasFixups && HasEnclosingCleanups)) { 727 assert(HasEnclosingCleanups); 728 EHScope &S = *EHStack.find(Scope.getEnclosingNormalCleanup()); 729 BranchThroughDest = CreateNormalEntry(*this, cast<EHCleanupScope>(S)); 730 } 731 732 llvm::BasicBlock *FallthroughDest = nullptr; 733 SmallVector<llvm::Instruction*, 2> InstsToAppend; 734 735 // If there's exactly one branch-after and no other threads, 736 // we can route it without a switch. 737 if (!Scope.hasBranchThroughs() && !HasFixups && !HasFallthrough && 738 Scope.getNumBranchAfters() == 1) { 739 assert(!BranchThroughDest || !IsActive); 740 741 // TODO: clean up the possibly dead stores to the cleanup dest slot. 742 llvm::BasicBlock *BranchAfter = Scope.getBranchAfterBlock(0); 743 InstsToAppend.push_back(llvm::BranchInst::Create(BranchAfter)); 744 745 // Build a switch-out if we need it: 746 // - if there are branch-afters threaded through the scope 747 // - if fall-through is a branch-after 748 // - if there are fixups that have nowhere left to go and 749 // so must be immediately resolved 750 } else if (Scope.getNumBranchAfters() || 751 (HasFallthrough && !FallthroughIsBranchThrough) || 752 (HasFixups && !HasEnclosingCleanups)) { 753 754 llvm::BasicBlock *Default = 755 (BranchThroughDest ? BranchThroughDest : getUnreachableBlock()); 756 757 // TODO: base this on the number of branch-afters and fixups 758 const unsigned SwitchCapacity = 10; 759 760 llvm::LoadInst *Load = 761 new llvm::LoadInst(getNormalCleanupDestSlot(), "cleanup.dest"); 762 llvm::SwitchInst *Switch = 763 llvm::SwitchInst::Create(Load, Default, SwitchCapacity); 764 765 InstsToAppend.push_back(Load); 766 InstsToAppend.push_back(Switch); 767 768 // Branch-after fallthrough. 769 if (FallthroughSource && !FallthroughIsBranchThrough) { 770 FallthroughDest = createBasicBlock("cleanup.cont"); 771 if (HasFallthrough) 772 Switch->addCase(Builder.getInt32(0), FallthroughDest); 773 } 774 775 for (unsigned I = 0, E = Scope.getNumBranchAfters(); I != E; ++I) { 776 Switch->addCase(Scope.getBranchAfterIndex(I), 777 Scope.getBranchAfterBlock(I)); 778 } 779 780 // If there aren't any enclosing cleanups, we can resolve all 781 // the fixups now. 782 if (HasFixups && !HasEnclosingCleanups) 783 ResolveAllBranchFixups(*this, Switch, NormalEntry); 784 } else { 785 // We should always have a branch-through destination in this case. 786 assert(BranchThroughDest); 787 InstsToAppend.push_back(llvm::BranchInst::Create(BranchThroughDest)); 788 } 789 790 // IV. Pop the cleanup and emit it. 791 EHStack.popCleanup(); 792 assert(EHStack.hasNormalCleanups() == HasEnclosingCleanups); 793 794 EmitCleanup(*this, Fn, cleanupFlags, NormalActiveFlag); 795 796 // Append the prepared cleanup prologue from above. 797 llvm::BasicBlock *NormalExit = Builder.GetInsertBlock(); 798 for (unsigned I = 0, E = InstsToAppend.size(); I != E; ++I) 799 NormalExit->getInstList().push_back(InstsToAppend[I]); 800 801 // Optimistically hope that any fixups will continue falling through. 802 for (unsigned I = FixupDepth, E = EHStack.getNumBranchFixups(); 803 I < E; ++I) { 804 BranchFixup &Fixup = EHStack.getBranchFixup(I); 805 if (!Fixup.Destination) continue; 806 if (!Fixup.OptimisticBranchBlock) { 807 new llvm::StoreInst(Builder.getInt32(Fixup.DestinationIndex), 808 getNormalCleanupDestSlot(), 809 Fixup.InitialBranch); 810 Fixup.InitialBranch->setSuccessor(0, NormalEntry); 811 } 812 Fixup.OptimisticBranchBlock = NormalExit; 813 } 814 815 // V. Set up the fallthrough edge out. 816 817 // Case 1: a fallthrough source exists but doesn't branch to the 818 // cleanup because the cleanup is inactive. 819 if (!HasFallthrough && FallthroughSource) { 820 // Prebranched fallthrough was forwarded earlier. 821 // Non-prebranched fallthrough doesn't need to be forwarded. 822 // Either way, all we need to do is restore the IP we cleared before. 823 assert(!IsActive); 824 Builder.restoreIP(savedInactiveFallthroughIP); 825 826 // Case 2: a fallthrough source exists and should branch to the 827 // cleanup, but we're not supposed to branch through to the next 828 // cleanup. 829 } else if (HasFallthrough && FallthroughDest) { 830 assert(!FallthroughIsBranchThrough); 831 EmitBlock(FallthroughDest); 832 833 // Case 3: a fallthrough source exists and should branch to the 834 // cleanup and then through to the next. 835 } else if (HasFallthrough) { 836 // Everything is already set up for this. 837 838 // Case 4: no fallthrough source exists. 839 } else { 840 Builder.ClearInsertionPoint(); 841 } 842 843 // VI. Assorted cleaning. 844 845 // Check whether we can merge NormalEntry into a single predecessor. 846 // This might invalidate (non-IR) pointers to NormalEntry. 847 llvm::BasicBlock *NewNormalEntry = 848 SimplifyCleanupEntry(*this, NormalEntry); 849 850 // If it did invalidate those pointers, and NormalEntry was the same 851 // as NormalExit, go back and patch up the fixups. 852 if (NewNormalEntry != NormalEntry && NormalEntry == NormalExit) 853 for (unsigned I = FixupDepth, E = EHStack.getNumBranchFixups(); 854 I < E; ++I) 855 EHStack.getBranchFixup(I).OptimisticBranchBlock = NewNormalEntry; 856 } 857 } 858 859 assert(EHStack.hasNormalCleanups() || EHStack.getNumBranchFixups() == 0); 860 861 // Emit the EH cleanup if required. 862 if (RequiresEHCleanup) { 863 CGDebugInfo *DI = getDebugInfo(); 864 SaveAndRestoreLocation AutoRestoreLocation(*this, Builder); 865 if (DI) 866 DI->EmitLocation(Builder, CurEHLocation); 867 868 CGBuilderTy::InsertPoint SavedIP = Builder.saveAndClearIP(); 869 870 EmitBlock(EHEntry); 871 872 // We only actually emit the cleanup code if the cleanup is either 873 // active or was used before it was deactivated. 874 if (EHActiveFlag || IsActive) { 875 876 cleanupFlags.setIsForEHCleanup(); 877 EmitCleanup(*this, Fn, cleanupFlags, EHActiveFlag); 878 } 879 880 Builder.CreateBr(getEHDispatchBlock(EHParent)); 881 882 Builder.restoreIP(SavedIP); 883 884 SimplifyCleanupEntry(*this, EHEntry); 885 } 886 } 887 888 /// isObviouslyBranchWithoutCleanups - Return true if a branch to the 889 /// specified destination obviously has no cleanups to run. 'false' is always 890 /// a conservatively correct answer for this method. 891 bool CodeGenFunction::isObviouslyBranchWithoutCleanups(JumpDest Dest) const { 892 assert(Dest.getScopeDepth().encloses(EHStack.stable_begin()) 893 && "stale jump destination"); 894 895 // Calculate the innermost active normal cleanup. 896 EHScopeStack::stable_iterator TopCleanup = 897 EHStack.getInnermostActiveNormalCleanup(); 898 899 // If we're not in an active normal cleanup scope, or if the 900 // destination scope is within the innermost active normal cleanup 901 // scope, we don't need to worry about fixups. 902 if (TopCleanup == EHStack.stable_end() || 903 TopCleanup.encloses(Dest.getScopeDepth())) // works for invalid 904 return true; 905 906 // Otherwise, we might need some cleanups. 907 return false; 908 } 909 910 911 /// Terminate the current block by emitting a branch which might leave 912 /// the current cleanup-protected scope. The target scope may not yet 913 /// be known, in which case this will require a fixup. 914 /// 915 /// As a side-effect, this method clears the insertion point. 916 void CodeGenFunction::EmitBranchThroughCleanup(JumpDest Dest) { 917 assert(Dest.getScopeDepth().encloses(EHStack.stable_begin()) 918 && "stale jump destination"); 919 920 if (!HaveInsertPoint()) 921 return; 922 923 // Create the branch. 924 llvm::BranchInst *BI = Builder.CreateBr(Dest.getBlock()); 925 926 // Calculate the innermost active normal cleanup. 927 EHScopeStack::stable_iterator 928 TopCleanup = EHStack.getInnermostActiveNormalCleanup(); 929 930 // If we're not in an active normal cleanup scope, or if the 931 // destination scope is within the innermost active normal cleanup 932 // scope, we don't need to worry about fixups. 933 if (TopCleanup == EHStack.stable_end() || 934 TopCleanup.encloses(Dest.getScopeDepth())) { // works for invalid 935 Builder.ClearInsertionPoint(); 936 return; 937 } 938 939 // If we can't resolve the destination cleanup scope, just add this 940 // to the current cleanup scope as a branch fixup. 941 if (!Dest.getScopeDepth().isValid()) { 942 BranchFixup &Fixup = EHStack.addBranchFixup(); 943 Fixup.Destination = Dest.getBlock(); 944 Fixup.DestinationIndex = Dest.getDestIndex(); 945 Fixup.InitialBranch = BI; 946 Fixup.OptimisticBranchBlock = nullptr; 947 948 Builder.ClearInsertionPoint(); 949 return; 950 } 951 952 // Otherwise, thread through all the normal cleanups in scope. 953 954 // Store the index at the start. 955 llvm::ConstantInt *Index = Builder.getInt32(Dest.getDestIndex()); 956 new llvm::StoreInst(Index, getNormalCleanupDestSlot(), BI); 957 958 // Adjust BI to point to the first cleanup block. 959 { 960 EHCleanupScope &Scope = 961 cast<EHCleanupScope>(*EHStack.find(TopCleanup)); 962 BI->setSuccessor(0, CreateNormalEntry(*this, Scope)); 963 } 964 965 // Add this destination to all the scopes involved. 966 EHScopeStack::stable_iterator I = TopCleanup; 967 EHScopeStack::stable_iterator E = Dest.getScopeDepth(); 968 if (E.strictlyEncloses(I)) { 969 while (true) { 970 EHCleanupScope &Scope = cast<EHCleanupScope>(*EHStack.find(I)); 971 assert(Scope.isNormalCleanup()); 972 I = Scope.getEnclosingNormalCleanup(); 973 974 // If this is the last cleanup we're propagating through, tell it 975 // that there's a resolved jump moving through it. 976 if (!E.strictlyEncloses(I)) { 977 Scope.addBranchAfter(Index, Dest.getBlock()); 978 break; 979 } 980 981 // Otherwise, tell the scope that there's a jump propoagating 982 // through it. If this isn't new information, all the rest of 983 // the work has been done before. 984 if (!Scope.addBranchThrough(Dest.getBlock())) 985 break; 986 } 987 } 988 989 Builder.ClearInsertionPoint(); 990 } 991 992 static bool IsUsedAsNormalCleanup(EHScopeStack &EHStack, 993 EHScopeStack::stable_iterator C) { 994 // If we needed a normal block for any reason, that counts. 995 if (cast<EHCleanupScope>(*EHStack.find(C)).getNormalBlock()) 996 return true; 997 998 // Check whether any enclosed cleanups were needed. 999 for (EHScopeStack::stable_iterator 1000 I = EHStack.getInnermostNormalCleanup(); 1001 I != C; ) { 1002 assert(C.strictlyEncloses(I)); 1003 EHCleanupScope &S = cast<EHCleanupScope>(*EHStack.find(I)); 1004 if (S.getNormalBlock()) return true; 1005 I = S.getEnclosingNormalCleanup(); 1006 } 1007 1008 return false; 1009 } 1010 1011 static bool IsUsedAsEHCleanup(EHScopeStack &EHStack, 1012 EHScopeStack::stable_iterator cleanup) { 1013 // If we needed an EH block for any reason, that counts. 1014 if (EHStack.find(cleanup)->hasEHBranches()) 1015 return true; 1016 1017 // Check whether any enclosed cleanups were needed. 1018 for (EHScopeStack::stable_iterator 1019 i = EHStack.getInnermostEHScope(); i != cleanup; ) { 1020 assert(cleanup.strictlyEncloses(i)); 1021 1022 EHScope &scope = *EHStack.find(i); 1023 if (scope.hasEHBranches()) 1024 return true; 1025 1026 i = scope.getEnclosingEHScope(); 1027 } 1028 1029 return false; 1030 } 1031 1032 enum ForActivation_t { 1033 ForActivation, 1034 ForDeactivation 1035 }; 1036 1037 /// The given cleanup block is changing activation state. Configure a 1038 /// cleanup variable if necessary. 1039 /// 1040 /// It would be good if we had some way of determining if there were 1041 /// extra uses *after* the change-over point. 1042 static void SetupCleanupBlockActivation(CodeGenFunction &CGF, 1043 EHScopeStack::stable_iterator C, 1044 ForActivation_t kind, 1045 llvm::Instruction *dominatingIP) { 1046 EHCleanupScope &Scope = cast<EHCleanupScope>(*CGF.EHStack.find(C)); 1047 1048 // We always need the flag if we're activating the cleanup in a 1049 // conditional context, because we have to assume that the current 1050 // location doesn't necessarily dominate the cleanup's code. 1051 bool isActivatedInConditional = 1052 (kind == ForActivation && CGF.isInConditionalBranch()); 1053 1054 bool needFlag = false; 1055 1056 // Calculate whether the cleanup was used: 1057 1058 // - as a normal cleanup 1059 if (Scope.isNormalCleanup() && 1060 (isActivatedInConditional || IsUsedAsNormalCleanup(CGF.EHStack, C))) { 1061 Scope.setTestFlagInNormalCleanup(); 1062 needFlag = true; 1063 } 1064 1065 // - as an EH cleanup 1066 if (Scope.isEHCleanup() && 1067 (isActivatedInConditional || IsUsedAsEHCleanup(CGF.EHStack, C))) { 1068 Scope.setTestFlagInEHCleanup(); 1069 needFlag = true; 1070 } 1071 1072 // If it hasn't yet been used as either, we're done. 1073 if (!needFlag) return; 1074 1075 llvm::AllocaInst *var = Scope.getActiveFlag(); 1076 if (!var) { 1077 var = CGF.CreateTempAlloca(CGF.Builder.getInt1Ty(), "cleanup.isactive"); 1078 Scope.setActiveFlag(var); 1079 1080 assert(dominatingIP && "no existing variable and no dominating IP!"); 1081 1082 // Initialize to true or false depending on whether it was 1083 // active up to this point. 1084 llvm::Value *value = CGF.Builder.getInt1(kind == ForDeactivation); 1085 1086 // If we're in a conditional block, ignore the dominating IP and 1087 // use the outermost conditional branch. 1088 if (CGF.isInConditionalBranch()) { 1089 CGF.setBeforeOutermostConditional(value, var); 1090 } else { 1091 new llvm::StoreInst(value, var, dominatingIP); 1092 } 1093 } 1094 1095 CGF.Builder.CreateStore(CGF.Builder.getInt1(kind == ForActivation), var); 1096 } 1097 1098 /// Activate a cleanup that was created in an inactivated state. 1099 void CodeGenFunction::ActivateCleanupBlock(EHScopeStack::stable_iterator C, 1100 llvm::Instruction *dominatingIP) { 1101 assert(C != EHStack.stable_end() && "activating bottom of stack?"); 1102 EHCleanupScope &Scope = cast<EHCleanupScope>(*EHStack.find(C)); 1103 assert(!Scope.isActive() && "double activation"); 1104 1105 SetupCleanupBlockActivation(*this, C, ForActivation, dominatingIP); 1106 1107 Scope.setActive(true); 1108 } 1109 1110 /// Deactive a cleanup that was created in an active state. 1111 void CodeGenFunction::DeactivateCleanupBlock(EHScopeStack::stable_iterator C, 1112 llvm::Instruction *dominatingIP) { 1113 assert(C != EHStack.stable_end() && "deactivating bottom of stack?"); 1114 EHCleanupScope &Scope = cast<EHCleanupScope>(*EHStack.find(C)); 1115 assert(Scope.isActive() && "double deactivation"); 1116 1117 // If it's the top of the stack, just pop it. 1118 if (C == EHStack.stable_begin()) { 1119 // If it's a normal cleanup, we need to pretend that the 1120 // fallthrough is unreachable. 1121 CGBuilderTy::InsertPoint SavedIP = Builder.saveAndClearIP(); 1122 PopCleanupBlock(); 1123 Builder.restoreIP(SavedIP); 1124 return; 1125 } 1126 1127 // Otherwise, follow the general case. 1128 SetupCleanupBlockActivation(*this, C, ForDeactivation, dominatingIP); 1129 1130 Scope.setActive(false); 1131 } 1132 1133 llvm::Value *CodeGenFunction::getNormalCleanupDestSlot() { 1134 if (!NormalCleanupDest) 1135 NormalCleanupDest = 1136 CreateTempAlloca(Builder.getInt32Ty(), "cleanup.dest.slot"); 1137 return NormalCleanupDest; 1138 } 1139 1140 /// Emits all the code to cause the given temporary to be cleaned up. 1141 void CodeGenFunction::EmitCXXTemporary(const CXXTemporary *Temporary, 1142 QualType TempType, 1143 llvm::Value *Ptr) { 1144 pushDestroy(NormalAndEHCleanup, Ptr, TempType, destroyCXXObject, 1145 /*useEHCleanup*/ true); 1146 } 1147