From: John McCall <rjmccall@apple.com>
Date: Tue, 14 Sep 2010 07:57:04 +0000 (+0000)
Subject: Implement the EH cleanup to call 'operator delete' if a new-expression throws
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=7d8647f194ae4f2499e5bcd40dcfea34cd21ebc6;p=clang
Implement the EH cleanup to call 'operator delete' if a new-expression throws
(but not if destructors associated with the full-expression throw).
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@113836 91177308-0d34-0410-b5e6-96231b3b80d8
---
diff --git a/lib/CodeGen/CGException.h b/lib/CodeGen/CGException.h
index f1294746a4..ce8bd49751 100644
--- a/lib/CodeGen/CGException.h
+++ b/lib/CodeGen/CGException.h
@@ -160,11 +160,14 @@ class EHCleanupScope : public EHScope {
/// Whether this cleanup needs to be run along exception edges.
bool IsEHCleanup : 1;
- /// Whether this cleanup was activated before all normal uses.
- bool ActivatedBeforeNormalUse : 1;
+ /// Whether this cleanup is currently active.
+ bool IsActive : 1;
- /// Whether this cleanup was activated before all EH uses.
- bool ActivatedBeforeEHUse : 1;
+ /// Whether the normal cleanup should test the activation flag.
+ bool TestFlagInNormalCleanup : 1;
+
+ /// Whether the EH cleanup should test the activation flag.
+ bool TestFlagInEHCleanup : 1;
/// The amount of extra storage needed by the Cleanup.
/// Always a multiple of the scope-stack alignment.
@@ -173,7 +176,7 @@ class EHCleanupScope : public EHScope {
/// The number of fixups required by enclosing scopes (not including
/// this one). If this is the top cleanup scope, all the fixups
/// from this index onwards belong to this scope.
- unsigned FixupDepth : BitsRemaining - 16;
+ unsigned FixupDepth : BitsRemaining - 17; // currently 13
/// The nearest normal cleanup scope enclosing this one.
EHScopeStack::stable_iterator EnclosingNormal;
@@ -190,12 +193,8 @@ class EHCleanupScope : public EHScope {
llvm::BasicBlock *EHBlock;
/// An optional i1 variable indicating whether this cleanup has been
- /// activated yet. This has one of three states:
- /// - it is null if the cleanup is inactive
- /// - it is activeSentinel() if the cleanup is active and was not
- /// required before activation
- /// - it points to a valid variable
- llvm::AllocaInst *ActiveVar;
+ /// activated yet.
+ llvm::AllocaInst *ActiveFlag;
/// Extra information required for cleanups that have resolved
/// branches through them. This has to be allocated on the side
@@ -246,14 +245,11 @@ public:
EHScopeStack::stable_iterator EnclosingNormal,
EHScopeStack::stable_iterator EnclosingEH)
: EHScope(EHScope::Cleanup),
- IsNormalCleanup(IsNormal), IsEHCleanup(IsEH),
- ActivatedBeforeNormalUse(IsActive),
- ActivatedBeforeEHUse(IsActive),
+ IsNormalCleanup(IsNormal), IsEHCleanup(IsEH), IsActive(IsActive),
+ TestFlagInNormalCleanup(false), TestFlagInEHCleanup(false),
CleanupSize(CleanupSize), FixupDepth(FixupDepth),
EnclosingNormal(EnclosingNormal), EnclosingEH(EnclosingEH),
- NormalBlock(0), EHBlock(0),
- ActiveVar(IsActive ? activeSentinel() : 0),
- ExtInfo(0)
+ NormalBlock(0), EHBlock(0), ActiveFlag(0), ExtInfo(0)
{
assert(this->CleanupSize == CleanupSize && "cleanup size overflow");
}
@@ -270,19 +266,17 @@ public:
llvm::BasicBlock *getEHBlock() const { return EHBlock; }
void setEHBlock(llvm::BasicBlock *BB) { EHBlock = BB; }
- static llvm::AllocaInst *activeSentinel() {
- return reinterpret_cast<llvm::AllocaInst*>(1);
- }
+ bool isActive() const { return IsActive; }
+ void setActive(bool A) { IsActive = A; }
- bool isActive() const { return ActiveVar != 0; }
- llvm::AllocaInst *getActiveVar() const { return ActiveVar; }
- void setActiveVar(llvm::AllocaInst *Var) { ActiveVar = Var; }
+ llvm::AllocaInst *getActiveFlag() const { return ActiveFlag; }
+ void setActiveFlag(llvm::AllocaInst *Var) { ActiveFlag = Var; }
- bool wasActivatedBeforeNormalUse() const { return ActivatedBeforeNormalUse; }
- void setActivatedBeforeNormalUse(bool B) { ActivatedBeforeNormalUse = B; }
+ void setTestFlagInNormalCleanup() { TestFlagInNormalCleanup = true; }
+ bool shouldTestFlagInNormalCleanup() const { return TestFlagInNormalCleanup; }
- bool wasActivatedBeforeEHUse() const { return ActivatedBeforeEHUse; }
- void setActivatedBeforeEHUse(bool B) { ActivatedBeforeEHUse = B; }
+ void setTestFlagInEHCleanup() { TestFlagInEHCleanup = true; }
+ bool shouldTestFlagInEHCleanup() const { return TestFlagInEHCleanup; }
unsigned getFixupDepth() const { return FixupDepth; }
EHScopeStack::stable_iterator getEnclosingNormalCleanup() const {
diff --git a/lib/CodeGen/CGExprCXX.cpp b/lib/CodeGen/CGExprCXX.cpp
index acdbe06556..3c0023a606 100644
--- a/lib/CodeGen/CGExprCXX.cpp
+++ b/lib/CodeGen/CGExprCXX.cpp
@@ -677,6 +677,62 @@ static void EmitNewInitializer(CodeGenFunction &CGF, const CXXNewExpr *E,
StoreAnyExprIntoOneUnit(CGF, E, NewPtr);
}
+namespace {
+ /// A cleanup to call the given 'operator delete' function upon
+ /// abnormal exit from a new expression.
+ class CallDeleteDuringNew : public EHScopeStack::Cleanup {
+ size_t NumPlacementArgs;
+ const FunctionDecl *OperatorDelete;
+ llvm::Value *Ptr;
+ llvm::Value *AllocSize;
+
+ RValue *getPlacementArgs() { return reinterpret_cast<RValue*>(this+1); }
+
+ public:
+ static size_t getExtraSize(size_t NumPlacementArgs) {
+ return NumPlacementArgs * sizeof(RValue);
+ }
+
+ CallDeleteDuringNew(size_t NumPlacementArgs,
+ const FunctionDecl *OperatorDelete,
+ llvm::Value *Ptr,
+ llvm::Value *AllocSize)
+ : NumPlacementArgs(NumPlacementArgs), OperatorDelete(OperatorDelete),
+ Ptr(Ptr), AllocSize(AllocSize) {}
+
+ void setPlacementArg(unsigned I, RValue Arg) {
+ assert(I < NumPlacementArgs && "index out of range");
+ getPlacementArgs()[I] = Arg;
+ }
+
+ void Emit(CodeGenFunction &CGF, bool IsForEH) {
+ const FunctionProtoType *FPT
+ = OperatorDelete->getType()->getAs<FunctionProtoType>();
+ assert(FPT->getNumArgs() == NumPlacementArgs + 1 ||
+ FPT->getNumArgs() == NumPlacementArgs + 2);
+
+ CallArgList DeleteArgs;
+
+ // The first argument is always a void*.
+ FunctionProtoType::arg_type_iterator AI = FPT->arg_type_begin();
+ DeleteArgs.push_back(std::make_pair(RValue::get(Ptr), *AI++));
+
+ // A member 'operator delete' can take an extra 'size_t' argument.
+ if (FPT->getNumArgs() == NumPlacementArgs + 2)
+ DeleteArgs.push_back(std::make_pair(RValue::get(AllocSize), *AI++));
+
+ // Pass the rest of the arguments, which must match exactly.
+ for (unsigned I = 0; I != NumPlacementArgs; ++I)
+ DeleteArgs.push_back(std::make_pair(getPlacementArgs()[I], *AI++));
+
+ // Call 'operator delete'.
+ CGF.EmitCall(CGF.CGM.getTypes().getFunctionInfo(DeleteArgs, FPT),
+ CGF.CGM.GetAddrOfFunction(OperatorDelete),
+ ReturnValueSlot(), DeleteArgs, OperatorDelete);
+ }
+ };
+}
+
llvm::Value *CodeGenFunction::EmitCXXNewExpr(const CXXNewExpr *E) {
QualType AllocType = E->getAllocatedType();
if (AllocType->isArrayType())
@@ -769,9 +825,24 @@ llvm::Value *CodeGenFunction::EmitCXXNewExpr(const CXXNewExpr *E) {
AllocType);
}
+ // If there's an operator delete, enter a cleanup to call it if an
+ // exception is thrown.
+ EHScopeStack::stable_iterator CallOperatorDelete;
+ if (E->getOperatorDelete()) {
+ CallDeleteDuringNew *Cleanup = CGF.EHStack
+ .pushCleanupWithExtra<CallDeleteDuringNew>(EHCleanup,
+ E->getNumPlacementArgs(),
+ E->getOperatorDelete(),
+ NewPtr, AllocSize);
+ for (unsigned I = 0, N = E->getNumPlacementArgs(); I != N; ++I)
+ Cleanup->setPlacementArg(I, NewArgs[I+1].first);
+ CallOperatorDelete = EHStack.stable_begin();
+ }
+
const llvm::Type *ElementPtrTy
= ConvertTypeForMem(AllocType)->getPointerTo(AS);
NewPtr = Builder.CreateBitCast(NewPtr, ElementPtrTy);
+
if (E->isArray()) {
EmitNewInitializer(*this, E, NewPtr, NumElements, AllocSizeWithoutCookie);
@@ -784,6 +855,11 @@ llvm::Value *CodeGenFunction::EmitCXXNewExpr(const CXXNewExpr *E) {
} else {
EmitNewInitializer(*this, E, NewPtr, NumElements, AllocSizeWithoutCookie);
}
+
+ // Deactivate the 'operator delete' cleanup if we finished
+ // initialization.
+ if (CallOperatorDelete.isValid())
+ DeactivateCleanupBlock(CallOperatorDelete);
if (NullCheckResult) {
Builder.CreateBr(NewEnd);
diff --git a/lib/CodeGen/CodeGenFunction.cpp b/lib/CodeGen/CodeGenFunction.cpp
index 51d084e1d3..0dbc6120ed 100644
--- a/lib/CodeGen/CodeGenFunction.cpp
+++ b/lib/CodeGen/CodeGenFunction.cpp
@@ -759,11 +759,51 @@ static llvm::BasicBlock *SimplifyCleanupEntry(CodeGenFunction &CGF,
static void EmitCleanup(CodeGenFunction &CGF,
EHScopeStack::Cleanup *Fn,
- bool ForEH) {
+ bool ForEH,
+ llvm::Value *ActiveFlag) {
+ // EH cleanups always occur within a terminate scope.
if (ForEH) CGF.EHStack.pushTerminate();
+
+ // If there's an active flag, load it and skip the cleanup if it's
+ // false.
+ llvm::BasicBlock *ContBB = 0;
+ if (ActiveFlag) {
+ ContBB = CGF.createBasicBlock("cleanup.done");
+ llvm::BasicBlock *CleanupBB = CGF.createBasicBlock("cleanup.action");
+ llvm::Value *IsActive
+ = CGF.Builder.CreateLoad(ActiveFlag, "cleanup.is_active");
+ CGF.Builder.CreateCondBr(IsActive, CleanupBB, ContBB);
+ CGF.EmitBlock(CleanupBB);
+ }
+
+ // Ask the cleanup to emit itself.
Fn->Emit(CGF, ForEH);
- if (ForEH) CGF.EHStack.popTerminate();
assert(CGF.HaveInsertPoint() && "cleanup ended with no insertion point?");
+
+ // Emit the continuation block if there was an active flag.
+ if (ActiveFlag)
+ CGF.EmitBlock(ContBB);
+
+ // Leave the terminate scope.
+ if (ForEH) CGF.EHStack.popTerminate();
+}
+
+static void ForwardPrebranchedFallthrough(llvm::BasicBlock *Exit,
+ llvm::BasicBlock *From,
+ llvm::BasicBlock *To) {
+ // Exit is the exit block of a cleanup, so it always terminates in
+ // an unconditional branch or a switch.
+ llvm::TerminatorInst *Term = Exit->getTerminator();
+
+ if (llvm::BranchInst *Br = dyn_cast<llvm::BranchInst>(Term)) {
+ assert(Br->isUnconditional() && Br->getSuccessor(0) == From);
+ Br->setSuccessor(0, To);
+ } else {
+ llvm::SwitchInst *Switch = cast<llvm::SwitchInst>(Term);
+ for (unsigned I = 0, E = Switch->getNumSuccessors(); I != E; ++I)
+ if (Switch->getSuccessor(I) == From)
+ Switch->setSuccessor(I, To);
+ }
}
/// Pops a cleanup block. If the block includes a normal cleanup, the
@@ -774,7 +814,13 @@ void CodeGenFunction::PopCleanupBlock(bool FallthroughIsBranchThrough) {
assert(isa<EHCleanupScope>(*EHStack.begin()) && "top not a cleanup!");
EHCleanupScope &Scope = cast<EHCleanupScope>(*EHStack.begin());
assert(Scope.getFixupDepth() <= EHStack.getNumBranchFixups());
- assert(Scope.isActive() && "cleanup was still inactive when popped!");
+
+ // Remember activation information.
+ bool IsActive = Scope.isActive();
+ llvm::Value *NormalActiveFlag =
+ Scope.shouldTestFlagInNormalCleanup() ? Scope.getActiveFlag() : 0;
+ llvm::Value *EHActiveFlag =
+ Scope.shouldTestFlagInEHCleanup() ? Scope.getActiveFlag() : 0;
// Check whether we need an EH cleanup. This is only true if we've
// generated a lazy EH cleanup block.
@@ -791,7 +837,12 @@ void CodeGenFunction::PopCleanupBlock(bool FallthroughIsBranchThrough) {
// - whether there's a fallthrough
llvm::BasicBlock *FallthroughSource = Builder.GetInsertBlock();
- bool HasFallthrough = (FallthroughSource != 0);
+ bool HasFallthrough = (FallthroughSource != 0 && IsActive);
+
+ // As a kindof crazy internal case, branch-through fall-throughs
+ // leave the insertion point set to the end of the last cleanup.
+ bool HasPrebranchedFallthrough =
+ (FallthroughSource && FallthroughSource->getTerminator());
bool RequiresNormalCleanup = false;
if (Scope.isNormalCleanup() &&
@@ -799,6 +850,40 @@ void CodeGenFunction::PopCleanupBlock(bool FallthroughIsBranchThrough) {
RequiresNormalCleanup = true;
}
+ assert(!HasPrebranchedFallthrough || RequiresNormalCleanup || !IsActive);
+ assert(!HasPrebranchedFallthrough ||
+ (Scope.isNormalCleanup() && Scope.getNormalBlock() &&
+ FallthroughSource->getTerminator()->getSuccessor(0)
+ == Scope.getNormalBlock()));
+
+ // Even if we don't need the normal cleanup, we might still have
+ // prebranched fallthrough to worry about.
+ if (!RequiresNormalCleanup && HasPrebranchedFallthrough) {
+ assert(!IsActive);
+
+ llvm::BasicBlock *NormalEntry = Scope.getNormalBlock();
+
+ // If we're branching through this cleanup, just forward the
+ // prebranched fallthrough to the next cleanup, leaving the insert
+ // point in the old block.
+ if (FallthroughIsBranchThrough) {
+ EHScope &S = *EHStack.find(Scope.getEnclosingNormalCleanup());
+ llvm::BasicBlock *EnclosingEntry =
+ CreateNormalEntry(*this, cast<EHCleanupScope>(S));
+
+ ForwardPrebranchedFallthrough(FallthroughSource,
+ NormalEntry, EnclosingEntry);
+ assert(NormalEntry->use_empty() &&
+ "uses of entry remain after forwarding?");
+ delete NormalEntry;
+
+ // Otherwise, we're branching out; just emit the next block.
+ } else {
+ EmitBlock(NormalEntry);
+ SimplifyCleanupEntry(*this, NormalEntry);
+ }
+ }
+
// If we don't need the cleanup at all, we're done.
if (!RequiresNormalCleanup && !RequiresEHCleanup) {
EHStack.popCleanup(); // safe because there are no fixups
@@ -877,14 +962,6 @@ void CodeGenFunction::PopCleanupBlock(bool FallthroughIsBranchThrough) {
if (!RequiresNormalCleanup) {
EHStack.popCleanup();
} else {
- // As a kindof crazy internal case, branch-through fall-throughs
- // leave the insertion point set to the end of the last cleanup.
- bool HasPrebranchedFallthrough =
- (HasFallthrough && FallthroughSource->getTerminator());
- assert(!HasPrebranchedFallthrough ||
- FallthroughSource->getTerminator()->getSuccessor(0)
- == Scope.getNormalBlock());
-
// If we have a fallthrough and no other need for the cleanup,
// emit it directly.
if (HasFallthrough && !HasPrebranchedFallthrough &&
@@ -901,7 +978,7 @@ void CodeGenFunction::PopCleanupBlock(bool FallthroughIsBranchThrough) {
EHStack.popCleanup();
- EmitCleanup(*this, Fn, /*ForEH*/ false);
+ EmitCleanup(*this, Fn, /*ForEH*/ false, NormalActiveFlag);
// Otherwise, the best approach is to thread everything through
// the cleanup block and then try to clean up after ourselves.
@@ -909,16 +986,30 @@ void CodeGenFunction::PopCleanupBlock(bool FallthroughIsBranchThrough) {
// Force the entry block to exist.
llvm::BasicBlock *NormalEntry = CreateNormalEntry(*this, Scope);
+ // I. Set up the fallthrough edge in.
+
// If there's a fallthrough, we need to store the cleanup
// destination index. For fall-throughs this is always zero.
- if (HasFallthrough && !HasPrebranchedFallthrough)
- Builder.CreateStore(Builder.getInt32(0), getNormalCleanupDestSlot());
+ if (HasFallthrough) {
+ if (!HasPrebranchedFallthrough)
+ Builder.CreateStore(Builder.getInt32(0), getNormalCleanupDestSlot());
+
+ // Otherwise, clear the IP if we don't have fallthrough because
+ // the cleanup is inactive. We don't need to save it because
+ // it's still just FallthroughSource.
+ } else if (FallthroughSource) {
+ assert(!IsActive && "source without fallthrough for active cleanup");
+ Builder.ClearInsertionPoint();
+ }
- // Emit the entry block. This implicitly branches to it if we
- // have fallthrough. All the fixups and existing branches should
- // already be branched to it.
+ // II. Emit the entry block. This implicitly branches to it if
+ // we have fallthrough. All the fixups and existing branches
+ // should already be branched to it.
EmitBlock(NormalEntry);
+ // III. Figure out where we're going and build the cleanup
+ // epilogue.
+
bool HasEnclosingCleanups =
(Scope.getEnclosingNormalCleanup() != EHStack.stable_end());
@@ -929,7 +1020,7 @@ void CodeGenFunction::PopCleanupBlock(bool FallthroughIsBranchThrough) {
// to the enclosing cleanup
llvm::BasicBlock *BranchThroughDest = 0;
if (Scope.hasBranchThroughs() ||
- (HasFallthrough && FallthroughIsBranchThrough) ||
+ (FallthroughSource && FallthroughIsBranchThrough) ||
(HasFixups && HasEnclosingCleanups)) {
assert(HasEnclosingCleanups);
EHScope &S = *EHStack.find(Scope.getEnclosingNormalCleanup());
@@ -943,7 +1034,7 @@ void CodeGenFunction::PopCleanupBlock(bool FallthroughIsBranchThrough) {
// we can route it without a switch.
if (!Scope.hasBranchThroughs() && !HasFixups && !HasFallthrough &&
Scope.getNumBranchAfters() == 1) {
- assert(!BranchThroughDest);
+ assert(!BranchThroughDest || !IsActive);
// TODO: clean up the possibly dead stores to the cleanup dest slot.
llvm::BasicBlock *BranchAfter = Scope.getBranchAfterBlock(0);
@@ -973,9 +1064,10 @@ void CodeGenFunction::PopCleanupBlock(bool FallthroughIsBranchThrough) {
InstsToAppend.push_back(Switch);
// Branch-after fallthrough.
- if (HasFallthrough && !FallthroughIsBranchThrough) {
+ if (FallthroughSource && !FallthroughIsBranchThrough) {
FallthroughDest = createBasicBlock("cleanup.cont");
- Switch->addCase(Builder.getInt32(0), FallthroughDest);
+ if (HasFallthrough)
+ Switch->addCase(Builder.getInt32(0), FallthroughDest);
}
for (unsigned I = 0, E = Scope.getNumBranchAfters(); I != E; ++I) {
@@ -991,11 +1083,11 @@ void CodeGenFunction::PopCleanupBlock(bool FallthroughIsBranchThrough) {
InstsToAppend.push_back(llvm::BranchInst::Create(BranchThroughDest));
}
- // We're finally ready to pop the cleanup.
+ // IV. Pop the cleanup and emit it.
EHStack.popCleanup();
assert(EHStack.hasNormalCleanups() == HasEnclosingCleanups);
- EmitCleanup(*this, Fn, /*ForEH*/ false);
+ EmitCleanup(*this, Fn, /*ForEH*/ false, NormalActiveFlag);
// Append the prepared cleanup prologue from above.
llvm::BasicBlock *NormalExit = Builder.GetInsertBlock();
@@ -1015,11 +1107,47 @@ void CodeGenFunction::PopCleanupBlock(bool FallthroughIsBranchThrough) {
}
Fixup.OptimisticBranchBlock = NormalExit;
}
+
+ // V. Set up the fallthrough edge out.
- if (FallthroughDest)
+ // Case 1: a fallthrough source exists but shouldn't branch to
+ // the cleanup because the cleanup is inactive.
+ if (!HasFallthrough && FallthroughSource) {
+ assert(!IsActive);
+
+ // If we have a prebranched fallthrough, that needs to be
+ // forwarded to the right block.
+ if (HasPrebranchedFallthrough) {
+ llvm::BasicBlock *Next;
+ if (FallthroughIsBranchThrough) {
+ Next = BranchThroughDest;
+ assert(!FallthroughDest);
+ } else {
+ Next = FallthroughDest;
+ }
+
+ ForwardPrebranchedFallthrough(FallthroughSource, NormalEntry, Next);
+ }
+ Builder.SetInsertPoint(FallthroughSource);
+
+ // Case 2: a fallthrough source exists and should branch to the
+ // cleanup, but we're not supposed to branch through to the next
+ // cleanup.
+ } else if (HasFallthrough && FallthroughDest) {
+ assert(!FallthroughIsBranchThrough);
EmitBlock(FallthroughDest);
- else if (!HasFallthrough)
+
+ // Case 3: a fallthrough source exists and should branch to the
+ // cleanup and then through to the next.
+ } else if (HasFallthrough) {
+ // Everything is already set up for this.
+
+ // Case 4: no fallthrough source exists.
+ } else {
Builder.ClearInsertionPoint();
+ }
+
+ // VI. Assorted cleaning.
// Check whether we can merge NormalEntry into a single predecessor.
// This might invalidate (non-IR) pointers to NormalEntry.
@@ -1042,7 +1170,7 @@ void CodeGenFunction::PopCleanupBlock(bool FallthroughIsBranchThrough) {
CGBuilderTy::InsertPoint SavedIP = Builder.saveAndClearIP();
EmitBlock(EHEntry);
- EmitCleanup(*this, Fn, /*ForEH*/ true);
+ EmitCleanup(*this, Fn, /*ForEH*/ true, EHActiveFlag);
// Append the prepared cleanup prologue from above.
llvm::BasicBlock *EHExit = Builder.GetInsertBlock();
@@ -1252,71 +1380,121 @@ void CodeGenFunction::ResolveBranchFixups(llvm::BasicBlock *Block) {
EHStack.popNullFixups();
}
-/// Activate a cleanup that was created in an inactivated state.
-void CodeGenFunction::ActivateCleanup(EHScopeStack::stable_iterator C) {
- assert(C != EHStack.stable_end() && "activating bottom of stack?");
- EHCleanupScope &Scope = cast<EHCleanupScope>(*EHStack.find(C));
- assert(!Scope.isActive() && "double activation");
+static bool IsUsedAsNormalCleanup(EHScopeStack &EHStack,
+ EHScopeStack::stable_iterator C) {
+ // If we needed a normal block for any reason, that counts.
+ if (cast<EHCleanupScope>(*EHStack.find(C)).getNormalBlock())
+ return true;
+
+ // Check whether any enclosed cleanups were needed.
+ for (EHScopeStack::stable_iterator
+ I = EHStack.getInnermostNormalCleanup();
+ I != C; ) {
+ assert(C.strictlyEncloses(I));
+ EHCleanupScope &S = cast<EHCleanupScope>(*EHStack.find(I));
+ if (S.getNormalBlock()) return true;
+ I = S.getEnclosingNormalCleanup();
+ }
+
+ return false;
+}
+
+static bool IsUsedAsEHCleanup(EHScopeStack &EHStack,
+ EHScopeStack::stable_iterator C) {
+ // If we needed an EH block for any reason, that counts.
+ if (cast<EHCleanupScope>(*EHStack.find(C)).getEHBlock())
+ return true;
+
+ // Check whether any enclosed cleanups were needed.
+ for (EHScopeStack::stable_iterator
+ I = EHStack.getInnermostEHCleanup(); I != C; ) {
+ assert(C.strictlyEncloses(I));
+ EHCleanupScope &S = cast<EHCleanupScope>(*EHStack.find(I));
+ if (S.getEHBlock()) return true;
+ I = S.getEnclosingEHCleanup();
+ }
+
+ return false;
+}
+
+enum ForActivation_t {
+ ForActivation,
+ ForDeactivation
+};
+
+/// The given cleanup block is changing activation state. Configure a
+/// cleanup variable if necessary.
+///
+/// It would be good if we had some way of determining if there were
+/// extra uses *after* the change-over point.
+static void SetupCleanupBlockActivation(CodeGenFunction &CGF,
+ EHScopeStack::stable_iterator C,
+ ForActivation_t Kind) {
+ EHCleanupScope &Scope = cast<EHCleanupScope>(*CGF.EHStack.find(C));
+ assert(!Scope.getActiveFlag() && "scope already has activation flag");
+
+ bool NeedFlag = false;
// Calculate whether the cleanup was used:
- bool Used = false;
// - as a normal cleanup
- if (Scope.isNormalCleanup()) {
- bool NormalUsed = false;
- if (Scope.getNormalBlock()) {
- NormalUsed = true;
- } else {
- // Check whether any enclosed cleanups were needed.
- for (EHScopeStack::stable_iterator
- I = EHStack.getInnermostNormalCleanup(); I != C; ) {
- assert(C.strictlyEncloses(I));
- EHCleanupScope &S = cast<EHCleanupScope>(*EHStack.find(I));
- if (S.getNormalBlock()) {
- NormalUsed = true;
- break;
- }
- I = S.getEnclosingNormalCleanup();
- }
- }
-
- if (NormalUsed)
- Used = true;
- else
- Scope.setActivatedBeforeNormalUse(true);
+ if (Scope.isNormalCleanup() && IsUsedAsNormalCleanup(CGF.EHStack, C)) {
+ Scope.setTestFlagInNormalCleanup();
+ NeedFlag = true;
}
// - as an EH cleanup
- if (Scope.isEHCleanup()) {
- bool EHUsed = false;
- if (Scope.getEHBlock()) {
- EHUsed = true;
- } else {
- // Check whether any enclosed cleanups were needed.
- for (EHScopeStack::stable_iterator
- I = EHStack.getInnermostEHCleanup(); I != C; ) {
- assert(C.strictlyEncloses(I));
- EHCleanupScope &S = cast<EHCleanupScope>(*EHStack.find(I));
- if (S.getEHBlock()) {
- EHUsed = true;
- break;
- }
- I = S.getEnclosingEHCleanup();
- }
- }
+ if (Scope.isEHCleanup() && IsUsedAsEHCleanup(CGF.EHStack, C)) {
+ Scope.setTestFlagInEHCleanup();
+ NeedFlag = true;
+ }
- if (EHUsed)
- Used = true;
- else
- Scope.setActivatedBeforeEHUse(true);
+ // If it hasn't yet been used as either, we're done.
+ if (!NeedFlag) return;
+
+ llvm::AllocaInst *Var = CGF.CreateTempAlloca(CGF.Builder.getInt1Ty());
+ Scope.setActiveFlag(Var);
+
+ if (Kind == ForActivation) {
+ CGF.InitTempAlloca(Var, CGF.Builder.getFalse());
+ CGF.Builder.CreateStore(CGF.Builder.getTrue(), Var);
+ } else {
+ CGF.InitTempAlloca(Var, CGF.Builder.getTrue());
+ CGF.Builder.CreateStore(CGF.Builder.getFalse(), Var);
}
-
- llvm::AllocaInst *Var = EHCleanupScope::activeSentinel();
- if (Used) {
- Var = CreateTempAlloca(Builder.getInt1Ty());
- InitTempAlloca(Var, Builder.getFalse());
+}
+
+/// Activate a cleanup that was created in an inactivated state.
+void CodeGenFunction::ActivateCleanupBlock(EHScopeStack::stable_iterator C) {
+ assert(C != EHStack.stable_end() && "activating bottom of stack?");
+ EHCleanupScope &Scope = cast<EHCleanupScope>(*EHStack.find(C));
+ assert(!Scope.isActive() && "double activation");
+
+ SetupCleanupBlockActivation(*this, C, ForActivation);
+
+ Scope.setActive(true);
+}
+
+/// Deactive a cleanup that was created in an active state.
+void CodeGenFunction::DeactivateCleanupBlock(EHScopeStack::stable_iterator C) {
+ assert(C != EHStack.stable_end() && "deactivating bottom of stack?");
+ EHCleanupScope &Scope = cast<EHCleanupScope>(*EHStack.find(C));
+ assert(Scope.isActive() && "double activation");
+
+ // If it's the top of the stack, just pop it.
+ if (C == EHStack.stable_begin()) {
+ // If it's a normal cleanup, we need to pretend that the
+ // fallthrough is unreachable.
+ CGBuilderTy::InsertPoint SavedIP = Builder.saveAndClearIP();
+ PopCleanupBlock();
+ Builder.restoreIP(SavedIP);
+ return;
}
- Scope.setActiveVar(Var);
+
+ // Otherwise, follow the general case.
+ SetupCleanupBlockActivation(*this, C, ForDeactivation);
+
+ Scope.setActive(false);
}
llvm::Value *CodeGenFunction::getNormalCleanupDestSlot() {
diff --git a/lib/CodeGen/CodeGenFunction.h b/lib/CodeGen/CodeGenFunction.h
index acf1e4d7b3..715be3ce17 100644
--- a/lib/CodeGen/CodeGenFunction.h
+++ b/lib/CodeGen/CodeGenFunction.h
@@ -285,6 +285,25 @@ public:
(void) Obj;
}
+ // Feel free to add more variants of the following:
+
+ /// Push a cleanup with non-constant storage requirements on the
+ /// stack. The cleanup type must provide an additional static method:
+ /// static size_t getExtraSize(size_t);
+ /// The argument to this method will be the value N, which will also
+ /// be passed as the first argument to the constructor.
+ ///
+ /// The data stored in the extra storage must obey the same
+ /// restrictions as normal cleanup member data.
+ ///
+ /// The pointer returned from this method is valid until the cleanup
+ /// stack is modified.
+ template <class T, class A0, class A1, class A2>
+ T *pushCleanupWithExtra(CleanupKind Kind, size_t N, A0 a0, A1 a1, A2 a2) {
+ void *Buffer = pushCleanup(Kind, sizeof(T) + T::getExtraSize(N));
+ return new (Buffer) T(N, a0, a1, a2);
+ }
+
/// Pops a cleanup scope off the stack. This should only be called
/// by CodeGenFunction::PopCleanupBlock.
void popCleanup();
@@ -542,7 +561,14 @@ public:
/// process all branch fixups.
void PopCleanupBlock(bool FallThroughIsBranchThrough = false);
- void ActivateCleanup(EHScopeStack::stable_iterator Cleanup);
+ /// DeactivateCleanupBlock - Deactivates the given cleanup block.
+ /// The block cannot be reactivated. Pops it if it's the top of the
+ /// stack.
+ void DeactivateCleanupBlock(EHScopeStack::stable_iterator Cleanup);
+
+ /// ActivateCleanupBlock - Activates an initially-inactive cleanup.
+ /// Cannot be used to resurrect a deactivated cleanup.
+ void ActivateCleanupBlock(EHScopeStack::stable_iterator Cleanup);
/// \brief Enters a new scope for capturing cleanups, all of which
/// will be executed once the scope is exited.
diff --git a/test/CodeGenCXX/exceptions.cpp b/test/CodeGenCXX/exceptions.cpp
index 4d8fb809ab..2337eee071 100644
--- a/test/CodeGenCXX/exceptions.cpp
+++ b/test/CodeGenCXX/exceptions.cpp
@@ -1,18 +1,210 @@
-// RUN: %clang_cc1 %s -triple=x86_64-apple-darwin10 -emit-llvm -o - -fexceptions
+// RUN: %clang_cc1 %s -triple=x86_64-apple-darwin10 -emit-llvm -o - -fexceptions | FileCheck %s
-struct allocator {
- allocator();
- allocator(const allocator&);
- ~allocator();
-};
+typedef typeof(sizeof(0)) size_t;
-void f();
-void g(bool b, bool c) {
- if (b) {
- if (!c)
- throw allocator();
+// This just shouldn't crash.
+namespace test0 {
+ struct allocator {
+ allocator();
+ allocator(const allocator&);
+ ~allocator();
+ };
- return;
+ void f();
+ void g(bool b, bool c) {
+ if (b) {
+ if (!c)
+ throw allocator();
+
+ return;
+ }
+ f();
+ }
+}
+
+namespace test1 {
+ struct A { A(int); A(int, int); ~A(); void *p; };
+
+ A *a() {
+ // CHECK: define [[A:%.*]]* @_ZN5test11aEv()
+ // CHECK: [[NEW:%.*]] = call noalias i8* @_Znwm(i64 8)
+ // CHECK-NEXT: [[CAST:%.*]] = bitcast i8* [[NEW]] to [[A]]*
+ // CHECK-NEXT: invoke void @_ZN5test11AC1Ei([[A]]* [[CAST]], i32 5)
+ // CHECK: ret [[A]]* [[CAST]]
+ // CHECK: call void @_ZdlPv(i8* [[NEW]])
+ return new A(5);
+ }
+
+ A *b() {
+ // CHECK: define [[A:%.*]]* @_ZN5test11bEv()
+ // CHECK: [[NEW:%.*]] = call noalias i8* @_Znwm(i64 8)
+ // CHECK-NEXT: [[CAST:%.*]] = bitcast i8* [[NEW]] to [[A]]*
+ // CHECK-NEXT: [[FOO:%.*]] = invoke i32 @_ZN5test13fooEv()
+ // CHECK: invoke void @_ZN5test11AC1Ei([[A]]* [[CAST]], i32 [[FOO]])
+ // CHECK: ret [[A]]* [[CAST]]
+ // CHECK: call void @_ZdlPv(i8* [[NEW]])
+ extern int foo();
+ return new A(foo());
+ }
+
+ struct B { B(); ~B(); operator int(); int x; };
+ B makeB();
+
+ A *c() {
+ // CHECK: define [[A:%.*]]* @_ZN5test11cEv()
+ // CHECK: [[ACTIVE:%.*]] = alloca i1
+ // CHECK-NEXT: store i1 true, i1* [[ACTIVE]]
+ // CHECK-NEXT: [[NEW:%.*]] = call noalias i8* @_Znwm(i64 8)
+ // CHECK-NEXT: [[CAST:%.*]] = bitcast i8* [[NEW]] to [[A]]*
+ // CHECK-NEXT: invoke void @_ZN5test11BC1Ev([[B:%.*]]* [[T0:%.*]])
+ // CHECK: [[T1:%.*]] = getelementptr inbounds [[B]]* [[T0]], i32 0, i32 0
+ // CHECK-NEXT: [[T2:%.*]] = load i32* [[T1]], align 4
+ // CHECK-NEXT: invoke void @_ZN5test11AC1Ei([[A]]* [[CAST]], i32 [[T2]])
+ // CHECK: store i1 false, i1* [[ACTIVE]]
+ // CHECK-NEXT: invoke void @_ZN5test11BD1Ev([[B]]* [[T0]])
+ // CHECK: ret [[A]]* [[CAST]]
+ // CHECK: [[ISACTIVE:%.*]] = load i1* [[ACTIVE]]
+ // CHECK-NEXT: br i1 [[ISACTIVE]]
+ // CHECK: call void @_ZdlPv(i8* [[NEW]])
+ return new A(B().x);
+ }
+
+ A *d() {
+ // CHECK: define [[A:%.*]]* @_ZN5test11dEv()
+ // CHECK: [[ACTIVE:%.*]] = alloca i1
+ // CHECK-NEXT: store i1 true, i1* [[ACTIVE]]
+ // CHECK-NEXT: [[NEW:%.*]] = call noalias i8* @_Znwm(i64 8)
+ // CHECK-NEXT: [[CAST:%.*]] = bitcast i8* [[NEW]] to [[A]]*
+ // CHECK-NEXT: invoke void @_ZN5test11BC1Ev([[B:%.*]]* [[T0:%.*]])
+ // CHECK: [[T1:%.*]] = invoke i32 @_ZN5test11BcviEv([[B]]* [[T0]])
+ // CHECK: invoke void @_ZN5test11AC1Ei([[A]]* [[CAST]], i32 [[T1]])
+ // CHECK: store i1 false, i1* [[ACTIVE]]
+ // CHECK-NEXT: invoke void @_ZN5test11BD1Ev([[B]]* [[T0]])
+ // CHECK: ret [[A]]* [[CAST]]
+ // CHECK: [[ISACTIVE:%.*]] = load i1* [[ACTIVE]]
+ // CHECK-NEXT: br i1 [[ISACTIVE]]
+ // CHECK: call void @_ZdlPv(i8* [[NEW]])
+ return new A(B());
+ }
+
+ A *e() {
+ // CHECK: define [[A:%.*]]* @_ZN5test11eEv()
+ // CHECK: [[ACTIVE:%.*]] = alloca i1
+ // CHECK-NEXT: store i1 true, i1* [[ACTIVE]]
+ // CHECK-NEXT: [[NEW:%.*]] = call noalias i8* @_Znwm(i64 8)
+ // CHECK-NEXT: [[CAST:%.*]] = bitcast i8* [[NEW]] to [[A]]*
+ // CHECK-NEXT: invoke void @_ZN5test11BC1Ev([[B:%.*]]* [[T0:%.*]])
+ // CHECK: [[T1:%.*]] = invoke i32 @_ZN5test11BcviEv([[B]]* [[T0]])
+ // CHECK: invoke void @_ZN5test11BC1Ev([[B]]* [[T2:%.*]])
+ // CHECK: [[T3:%.*]] = invoke i32 @_ZN5test11BcviEv([[B]]* [[T2]])
+ // CHECK: invoke void @_ZN5test11AC1Eii([[A]]* [[CAST]], i32 [[T1]], i32 [[T3]])
+ // CHECK: store i1 false, i1* [[ACTIVE]]
+ // CHECK-NEXT: invoke void @_ZN5test11BD1Ev([[B]]* [[T2]])
+ // CHECK: invoke void @_ZN5test11BD1Ev([[B]]* [[T0]])
+ // CHECK: ret [[A]]* [[CAST]]
+ // CHECK: [[ISACTIVE:%.*]] = load i1* [[ACTIVE]]
+ // CHECK-NEXT: br i1 [[ISACTIVE]]
+ // CHECK: call void @_ZdlPv(i8* [[NEW]])
+ return new A(B(), B());
+ }
+ A *f() {
+ return new A(makeB().x);
+ }
+ A *g() {
+ return new A(makeB());
+ }
+ A *h() {
+ return new A(makeB(), makeB());
}
- f();
+
+ A *i() {
+ // CHECK: define [[A:%.*]]* @_ZN5test11iEv()
+ // CHECK: [[X:%.*]] = alloca [[A]]*, align 8
+ // CHECK: [[ACTIVE:%.*]] = alloca i1
+ // CHECK: store i1 true, i1* [[ACTIVE]]
+ // CHECK-NEXT: [[NEW:%.*]] = call noalias i8* @_Znwm(i64 8)
+ // CHECK-NEXT: [[CAST:%.*]] = bitcast i8* [[NEW]] to [[A]]*
+ // CHECK-NEXT: invoke void @_ZN5test15makeBEv([[B:%.*]]* sret [[T0:%.*]])
+ // CHECK: [[T1:%.*]] = invoke i32 @_ZN5test11BcviEv([[B]]* [[T0]])
+ // CHECK: invoke void @_ZN5test11AC1Ei([[A]]* [[CAST]], i32 [[T1]])
+ // CHECK: store i1 false, i1* [[ACTIVE]]
+ // CHECK-NEXT: store [[A]]* [[CAST]], [[A]]** [[X]], align 8
+ // CHECK: invoke void @_ZN5test15makeBEv([[B:%.*]]* sret [[T2:%.*]])
+ // CHECK: [[RET:%.*]] = load [[A]]** [[X]], align 8
+ // CHECK: invoke void @_ZN5test11BD1Ev([[B]]* [[T2]])
+ // CHECK: invoke void @_ZN5test11BD1Ev([[B]]* [[T0]])
+ // CHECK: ret [[A]]* [[RET]]
+ // CHECK: [[ISACTIVE:%.*]] = load i1* [[ACTIVE]]
+ // CHECK-NEXT: br i1 [[ISACTIVE]]
+ // CHECK: call void @_ZdlPv(i8* [[NEW]])
+ A *x;
+ return (x = new A(makeB()), makeB(), x);
+ }
+}
+
+namespace test2 {
+ struct A {
+ A(int); A(int, int); ~A();
+ void *p;
+ void *operator new(size_t);
+ void operator delete(void*, size_t);
+ };
+
+ A *a() {
+ // CHECK: define [[A:%.*]]* @_ZN5test21aEv()
+ // CHECK: [[NEW:%.*]] = call i8* @_ZN5test21AnwEm(i64 8)
+ // CHECK-NEXT: [[CAST:%.*]] = bitcast i8* [[NEW]] to [[A]]*
+ // CHECK-NEXT: invoke void @_ZN5test21AC1Ei([[A]]* [[CAST]], i32 5)
+ // CHECK: ret [[A]]* [[CAST]]
+ // CHECK: invoke void @_ZN5test21AdlEPvm(i8* [[NEW]], i64 8)
+ // CHECK: call void @_ZSt9terminatev()
+ return new A(5);
+ }
+}
+
+namespace test3 {
+ struct A {
+ A(int); A(int, int); ~A();
+ void *p;
+ void *operator new(size_t, void*, void*);
+ void operator delete(void*, void*, void*);
+ };
+
+ A *a() {
+ // CHECK: define [[A:%.*]]* @_ZN5test31aEv()
+ // CHECK: [[FOO:%.*]] = call i8* @_ZN5test33fooEv()
+ // CHECK: [[BAR:%.*]] = call i8* @_ZN5test33barEv()
+ // CHECK: [[NEW:%.*]] = call i8* @_ZN5test31AnwEmPvS1_(i64 8, i8* [[FOO]], i8* [[BAR]])
+ // CHECK-NEXT: [[CAST:%.*]] = bitcast i8* [[NEW]] to [[A]]*
+ // CHECK-NEXT: invoke void @_ZN5test31AC1Ei([[A]]* [[CAST]], i32 5)
+ // CHECK: ret [[A]]* [[CAST]]
+ // CHECK: invoke void @_ZN5test31AdlEPvS1_S1_(i8* [[NEW]], i8* [[FOO]], i8* [[BAR]])
+ // CHECK: call void @_ZSt9terminatev()
+ extern void *foo(), *bar();
+
+ return new(foo(),bar()) A(5);
+ }
+}
+
+namespace test4 {
+ struct A {
+ A(int); A(int, int); ~A();
+ void *p;
+ void *operator new(size_t, void*, void*);
+ void operator delete(void*, size_t, void*, void*); // not a match
+ };
+
+ A *a() {
+ // CHECK: define [[A:%.*]]* @_ZN5test41aEv()
+ // CHECK: [[FOO:%.*]] = call i8* @_ZN5test43fooEv()
+ // CHECK-NEXT: [[BAR:%.*]] = call i8* @_ZN5test43barEv()
+ // CHECK-NEXT: [[NEW:%.*]] = call i8* @_ZN5test41AnwEmPvS1_(i64 8, i8* [[FOO]], i8* [[BAR]])
+ // CHECK-NEXT: [[CAST:%.*]] = bitcast i8* [[NEW]] to [[A]]*
+ // CHECK-NEXT: call void @_ZN5test41AC1Ei([[A]]* [[CAST]], i32 5)
+ // CHECK-NEXT: ret [[A]]* [[CAST]]
+ extern void *foo(), *bar();
+
+ return new(foo(),bar()) A(5);
+ }
+
}