r331016 - [CodeGen] Avoid destructing a callee-destructued struct type in a
Akira Hatanaka via cfe-commits
cfe-commits at lists.llvm.org
Thu Apr 26 21:21:51 PDT 2018
Author: ahatanak
Date: Thu Apr 26 21:21:51 2018
New Revision: 331016
URL: http://llvm.org/viewvc/llvm-project?rev=331016&view=rev
Log:
[CodeGen] Avoid destructing a callee-destructued struct type in a
function if a function delegates to another function.
Fix a bug introduced in r328731, which caused a struct with ObjC __weak
fields that was passed to a function to be destructed twice, once in the
callee function and once in another function the callee function
delegates to. To prevent this, keep track of the callee-destructed
structs passed to a function and disable their cleanups at the point of
the call to the delegated function.
rdar://problem/39194693
Differential Revision: https://reviews.llvm.org/D45382
Modified:
cfe/trunk/lib/CodeGen/CGCall.cpp
cfe/trunk/lib/CodeGen/CGCleanup.cpp
cfe/trunk/lib/CodeGen/CGDecl.cpp
cfe/trunk/lib/CodeGen/CodeGenFunction.h
cfe/trunk/test/CodeGenObjCXX/arc-forwarded-lambda-call.mm
cfe/trunk/test/CodeGenObjCXX/arc-special-member-functions.mm
cfe/trunk/test/CodeGenObjCXX/lambda-expressions.mm
Modified: cfe/trunk/lib/CodeGen/CGCall.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/CGCall.cpp?rev=331016&r1=331015&r2=331016&view=diff
==============================================================================
--- cfe/trunk/lib/CodeGen/CGCall.cpp (original)
+++ cfe/trunk/lib/CodeGen/CGCall.cpp Thu Apr 26 21:21:51 2018
@@ -3063,6 +3063,22 @@ void CodeGenFunction::EmitDelegateCallAr
} else {
args.add(convertTempToRValue(local, type, loc), type);
}
+
+ // Deactivate the cleanup for the callee-destructed param that was pushed.
+ if (hasAggregateEvaluationKind(type) &&
+ getContext().isParamDestroyedInCallee(type)) {
+ EHScopeStack::stable_iterator cleanup =
+ CalleeDestructedParamCleanups.lookup(cast<ParmVarDecl>(param));
+ if (cleanup.isValid()) {
+ // This unreachable is a temporary marker which will be removed later.
+ llvm::Instruction *isActive = Builder.CreateUnreachable();
+ args.addArgCleanupDeactivation(cleanup, isActive);
+ } else
+ // A param cleanup should have been pushed unless we are code-generating
+ // a thunk.
+ assert(CurFuncIsThunk &&
+ "cleanup for callee-destructed param not recorded");
+ }
}
static bool isProvablyNull(llvm::Value *addr) {
Modified: cfe/trunk/lib/CodeGen/CGCleanup.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/CGCleanup.cpp?rev=331016&r1=331015&r2=331016&view=diff
==============================================================================
--- cfe/trunk/lib/CodeGen/CGCleanup.cpp (original)
+++ cfe/trunk/lib/CodeGen/CGCleanup.cpp Thu Apr 26 21:21:51 2018
@@ -1233,8 +1233,10 @@ void CodeGenFunction::DeactivateCleanupB
EHCleanupScope &Scope = cast<EHCleanupScope>(*EHStack.find(C));
assert(Scope.isActive() && "double deactivation");
- // If it's the top of the stack, just pop it.
- if (C == EHStack.stable_begin()) {
+ // If it's the top of the stack, just pop it, but do so only if it belongs
+ // to the current RunCleanupsScope.
+ if (C == EHStack.stable_begin() &&
+ CurrentCleanupScopeDepth.strictlyEncloses(C)) {
// If it's a normal cleanup, we need to pretend that the
// fallthrough is unreachable.
CGBuilderTy::InsertPoint SavedIP = Builder.saveAndClearIP();
Modified: cfe/trunk/lib/CodeGen/CGDecl.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/CGDecl.cpp?rev=331016&r1=331015&r2=331016&view=diff
==============================================================================
--- cfe/trunk/lib/CodeGen/CGDecl.cpp (original)
+++ cfe/trunk/lib/CodeGen/CGDecl.cpp Thu Apr 26 21:21:51 2018
@@ -1962,6 +1962,8 @@ void CodeGenFunction::EmitParmDecl(const
DtorKind == QualType::DK_nontrivial_c_struct) &&
"unexpected destructor type");
pushDestroy(DtorKind, DeclPtr, Ty);
+ CalleeDestructedParamCleanups[cast<ParmVarDecl>(&D)] =
+ EHStack.stable_begin();
}
}
} else {
Modified: cfe/trunk/lib/CodeGen/CodeGenFunction.h
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/CodeGenFunction.h?rev=331016&r1=331015&r2=331016&view=diff
==============================================================================
--- cfe/trunk/lib/CodeGen/CodeGenFunction.h (original)
+++ cfe/trunk/lib/CodeGen/CodeGenFunction.h Thu Apr 26 21:21:51 2018
@@ -587,7 +587,7 @@ public:
/// \brief Enters a new scope for capturing cleanups, all of which
/// will be executed once the scope is exited.
class RunCleanupsScope {
- EHScopeStack::stable_iterator CleanupStackDepth;
+ EHScopeStack::stable_iterator CleanupStackDepth, OldCleanupScopeDepth;
size_t LifetimeExtendedCleanupStackSize;
bool OldDidCallStackSave;
protected:
@@ -610,6 +610,8 @@ public:
CGF.LifetimeExtendedCleanupStack.size();
OldDidCallStackSave = CGF.DidCallStackSave;
CGF.DidCallStackSave = false;
+ OldCleanupScopeDepth = CGF.CurrentCleanupScopeDepth;
+ CGF.CurrentCleanupScopeDepth = CleanupStackDepth;
}
/// \brief Exit this cleanup scope, emitting any accumulated cleanups.
@@ -635,9 +637,14 @@ public:
CGF.PopCleanupBlocks(CleanupStackDepth, LifetimeExtendedCleanupStackSize,
ValuesToReload);
PerformCleanup = false;
+ CGF.CurrentCleanupScopeDepth = OldCleanupScopeDepth;
}
};
+ // Cleanup stack depth of the RunCleanupsScope that was pushed most recently.
+ EHScopeStack::stable_iterator CurrentCleanupScopeDepth =
+ EHScopeStack::stable_end();
+
class LexicalScope : public RunCleanupsScope {
SourceRange Range;
SmallVector<const LabelDecl*, 4> Labels;
@@ -1095,6 +1102,11 @@ private:
/// decls.
DeclMapTy LocalDeclMap;
+ // Keep track of the cleanups for callee-destructed parameters pushed to the
+ // cleanup stack so that they can be deactivated later.
+ llvm::DenseMap<const ParmVarDecl *, EHScopeStack::stable_iterator>
+ CalleeDestructedParamCleanups;
+
/// SizeArguments - If a ParmVarDecl had the pass_object_size attribute, this
/// will contain a mapping from said ParmVarDecl to its implicit "object_size"
/// parameter.
Modified: cfe/trunk/test/CodeGenObjCXX/arc-forwarded-lambda-call.mm
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/CodeGenObjCXX/arc-forwarded-lambda-call.mm?rev=331016&r1=331015&r2=331016&view=diff
==============================================================================
--- cfe/trunk/test/CodeGenObjCXX/arc-forwarded-lambda-call.mm (original)
+++ cfe/trunk/test/CodeGenObjCXX/arc-forwarded-lambda-call.mm Thu Apr 26 21:21:51 2018
@@ -10,6 +10,17 @@ void test0(id x) {
// CHECK-NEXT: ret i8* [[T2]]
}
+// Check that the delegating block invoke function doesn't destruct the Weak
+// object that is passed.
+
+// CHECK-LABEL: define internal void @___Z8testWeakv_block_invoke(
+// CHECK: call void @"_ZZ8testWeakvENK3$_2clE4Weak"(
+// CHECK-NEXT: ret void
+
+// CHECK-LABEL: define internal void @"_ZZ8testWeakvENK3$_2clE4Weak"(
+// CHECK: call void @_ZN4WeakD1Ev(
+// CHECK-NEXT: ret void
+
id test1_rv;
void test1() {
@@ -21,3 +32,12 @@ void test1() {
// CHECK-NEXT: [[T2:%.*]] = tail call i8* @objc_autoreleaseReturnValue(i8* [[T1]])
// CHECK-NEXT: ret i8* [[T2]]
}
+
+struct Weak {
+ __weak id x;
+};
+
+void testWeak() {
+ extern void testWeak_helper(void (^)(Weak));
+ testWeak_helper([](Weak){});
+}
Modified: cfe/trunk/test/CodeGenObjCXX/arc-special-member-functions.mm
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/CodeGenObjCXX/arc-special-member-functions.mm?rev=331016&r1=331015&r2=331016&view=diff
==============================================================================
--- cfe/trunk/test/CodeGenObjCXX/arc-special-member-functions.mm (original)
+++ cfe/trunk/test/CodeGenObjCXX/arc-special-member-functions.mm Thu Apr 26 21:21:51 2018
@@ -1,4 +1,4 @@
-// RUN: %clang_cc1 -fobjc-arc -fblocks -triple x86_64-apple-darwin10.0.0 -emit-llvm -o - %s | FileCheck %s
+// RUN: %clang_cc1 -std=c++11 -fobjc-arc -fblocks -triple x86_64-apple-darwin10.0.0 -fobjc-runtime-has-weak -emit-llvm -o - %s | FileCheck %s
struct ObjCMember {
id member;
@@ -12,6 +12,59 @@ struct ObjCBlockMember {
int (^bp)(int);
};
+// CHECK: %[[STRUCT_CONTAINSWEAK:.*]] = type { %[[STRUCT_WEAK:.*]] }
+// CHECK: %[[STRUCT_WEAK]] = type { i8* }
+
+// The Weak object that is passed is destructed in this constructor.
+
+// CHECK: define void @_ZN12ContainsWeakC2E4Weak(
+// CHECK: call void @_ZN4WeakC1ERKS_(
+// CHECK: call void @_ZN4WeakD1Ev(
+
+// Check that the Weak object passed to this constructor is not destructed after
+// the delegate constructor is called.
+
+// CHECK: define void @_ZN12ContainsWeakC1E4Weak(
+// CHECK: call void @_ZN12ContainsWeakC2E4Weak(
+// CHECK-NEXT: ret void
+
+struct Weak {
+ Weak(id);
+ __weak id x;
+};
+
+struct ContainsWeak {
+ ContainsWeak(Weak);
+ Weak w;
+};
+
+ContainsWeak::ContainsWeak(Weak a) : w(a) {}
+
+// The Weak object that is passed is destructed in this constructor.
+
+// CHECK: define void @_ZN4BaseC2E4Weak(
+// CHECK: call void @_ZN4WeakD1Ev(
+// CHECK: ret void
+
+// Check that the Weak object passed to this constructor is not destructed after
+// the delegate constructor is called.
+
+// CHECK: define linkonce_odr void @_ZN7DerivedCI14BaseE4Weak(
+// CHECK: call void @_ZN7DerivedCI24BaseE4Weak(
+// CHECK-NEXT: ret void
+
+struct Base {
+ Base(Weak);
+};
+
+Base::Base(Weak a) {}
+
+struct Derived : Base {
+ using Base::Base;
+};
+
+Derived d(Weak(0));
+
// CHECK-LABEL: define void @_Z42test_ObjCMember_default_construct_destructv(
void test_ObjCMember_default_construct_destruct() {
// CHECK: call void @_ZN10ObjCMemberC1Ev
@@ -111,6 +164,13 @@ void test_ObjCBlockMember_copy_assign(Ob
// CHECK-NEXT: call void @objc_release(i8* [[T7]])
// CHECK-NEXT: ret
+// Check that the Weak object passed to this constructor is not destructed after
+// the delegate constructor is called.
+
+// CHECK: define linkonce_odr void @_ZN7DerivedCI24BaseE4Weak(
+// CHECK: call void @_ZN4BaseC2E4Weak(
+// CHECK-NEXT: ret void
+
// Implicitly-generated default constructor for ObjCMember
// CHECK-LABEL: define linkonce_odr void @_ZN10ObjCMemberC2Ev
// CHECK-NOT: objc_release
Modified: cfe/trunk/test/CodeGenObjCXX/lambda-expressions.mm
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/CodeGenObjCXX/lambda-expressions.mm?rev=331016&r1=331015&r2=331016&view=diff
==============================================================================
--- cfe/trunk/test/CodeGenObjCXX/lambda-expressions.mm (original)
+++ cfe/trunk/test/CodeGenObjCXX/lambda-expressions.mm Thu Apr 26 21:21:51 2018
@@ -1,4 +1,4 @@
-// RUN: %clang_cc1 -triple x86_64-apple-darwin10.0.0 -emit-llvm -o - %s -fexceptions -std=c++11 -fblocks -fobjc-arc | FileCheck -check-prefix=ARC %s
+// RUN: %clang_cc1 -triple x86_64-apple-darwin10.0.0 -emit-llvm -o - %s -fexceptions -std=c++11 -fblocks -fobjc-arc -fobjc-runtime-has-weak -DWEAK_SUPPORTED | FileCheck -check-prefix=ARC %s
// RUN: %clang_cc1 -triple x86_64-apple-darwin10.0.0 -emit-llvm -o - %s -fexceptions -std=c++11 -fblocks | FileCheck -check-prefix=MRC %s
typedef int (^fp)();
@@ -138,5 +138,31 @@ namespace BlockInLambda {
}
@end
+// Check that the delegating invoke function doesn't destruct the Weak object
+// that is passed.
+
+// ARC-LABEL: define internal void @"_ZZN14LambdaDelegate4testEvEN3$_58__invokeENS_4WeakE"(
+// ARC: call void @"_ZZN14LambdaDelegate4testEvENK3$_5clENS_4WeakE"(
+// ARC-NEXT: ret void
+
+// ARC-LABEL: define internal void @"_ZZN14LambdaDelegate4testEvENK3$_5clENS_4WeakE"(
+// ARC: call void @_ZN14LambdaDelegate4WeakD1Ev(
+
+#ifdef WEAK_SUPPORTED
+
+namespace LambdaDelegate {
+
+struct Weak {
+ __weak id x;
+};
+
+void test() {
+ void (*p)(Weak) = [](Weak a) { };
+}
+
+};
+
+#endif
+
// ARC: attributes [[NUW]] = { noinline nounwind{{.*}} }
// MRC: attributes [[NUW]] = { noinline nounwind{{.*}} }
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