[cfe-commits] r133620 - in /cfe/trunk: lib/CodeGen/CGExpr.cpp lib/CodeGen/CGObjC.cpp lib/CodeGen/CodeGenFunction.h lib/Sema/SemaInit.cpp test/CodeGenObjCXX/arc-references.mm
Douglas Gregor
dgregor at apple.com
Wed Jun 22 09:12:01 PDT 2011
Author: dgregor
Date: Wed Jun 22 11:12:01 2011
New Revision: 133620
URL: http://llvm.org/viewvc/llvm-project?rev=133620&view=rev
Log:
When binding a reference to an Automatic Reference Counting temporary,
retain/release the temporary object appropriately. Previously, we
would only perform the retain/release operations when the reference
would extend the lifetime of the temporary, but this does the wrong
thing across calls.
Modified:
cfe/trunk/lib/CodeGen/CGExpr.cpp
cfe/trunk/lib/CodeGen/CGObjC.cpp
cfe/trunk/lib/CodeGen/CodeGenFunction.h
cfe/trunk/lib/Sema/SemaInit.cpp
cfe/trunk/test/CodeGenObjCXX/arc-references.mm
Modified: cfe/trunk/lib/CodeGen/CGExpr.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/CGExpr.cpp?rev=133620&r1=133619&r2=133620&view=diff
==============================================================================
--- cfe/trunk/lib/CodeGen/CGExpr.cpp (original)
+++ cfe/trunk/lib/CodeGen/CGExpr.cpp Wed Jun 22 11:12:01 2011
@@ -205,11 +205,21 @@
const CXXDestructorDecl *&ReferenceTemporaryDtor,
QualType &ObjCARCReferenceLifetimeType,
const NamedDecl *InitializedDecl) {
- ObjCARCReferenceLifetimeType = QualType();
-
// Look through expressions for materialized temporaries (for now).
- if (isa<MaterializeTemporaryExpr>(E))
- E = cast<MaterializeTemporaryExpr>(E)->GetTemporaryExpr();
+ if (const MaterializeTemporaryExpr *M
+ = dyn_cast<MaterializeTemporaryExpr>(E)) {
+ // Objective-C++ ARC:
+ // If we are binding a reference to a temporary that has ownership, we
+ // need to perform retain/release operations on the temporary.
+ if (CGF.getContext().getLangOptions().ObjCAutoRefCount &&
+ E->getType()->isObjCLifetimeType() &&
+ (E->getType().getObjCLifetime() == Qualifiers::OCL_Strong ||
+ E->getType().getObjCLifetime() == Qualifiers::OCL_Weak ||
+ E->getType().getObjCLifetime() == Qualifiers::OCL_Autoreleasing))
+ ObjCARCReferenceLifetimeType = E->getType();
+
+ E = M->GetTemporaryExpr();
+ }
if (const CXXDefaultArgExpr *DAE = dyn_cast<CXXDefaultArgExpr>(E))
E = DAE->getExpr();
@@ -243,6 +253,57 @@
// We have to load the lvalue.
RV = CGF.EmitLoadOfLValue(LV, E->getType());
} else {
+ if (!ObjCARCReferenceLifetimeType.isNull()) {
+ ReferenceTemporary = CreateReferenceTemporary(CGF,
+ ObjCARCReferenceLifetimeType,
+ InitializedDecl);
+
+
+ LValue RefTempDst = CGF.MakeAddrLValue(ReferenceTemporary,
+ ObjCARCReferenceLifetimeType);
+
+ CGF.EmitScalarInit(E, dyn_cast_or_null<ValueDecl>(InitializedDecl),
+ RefTempDst, false);
+
+ bool ExtendsLifeOfTemporary = false;
+ if (const VarDecl *Var = dyn_cast_or_null<VarDecl>(InitializedDecl)) {
+ if (Var->extendsLifetimeOfTemporary())
+ ExtendsLifeOfTemporary = true;
+ } else if (InitializedDecl && isa<FieldDecl>(InitializedDecl)) {
+ ExtendsLifeOfTemporary = true;
+ }
+
+ if (!ExtendsLifeOfTemporary) {
+ // Since the lifetime of this temporary isn't going to be extended,
+ // we need to clean it up ourselves at the end of the full expression.
+ switch (ObjCARCReferenceLifetimeType.getObjCLifetime()) {
+ case Qualifiers::OCL_None:
+ case Qualifiers::OCL_ExplicitNone:
+ case Qualifiers::OCL_Autoreleasing:
+ break;
+
+ case Qualifiers::OCL_Strong:
+ CGF.PushARCReleaseCleanup(CGF.getARCCleanupKind(),
+ ObjCARCReferenceLifetimeType,
+ ReferenceTemporary,
+ /*Precise lifetime=*/false,
+ /*For full expression=*/true);
+ break;
+
+ case Qualifiers::OCL_Weak:
+ CGF.PushARCWeakReleaseCleanup(NormalAndEHCleanup,
+ ObjCARCReferenceLifetimeType,
+ ReferenceTemporary,
+ /*For full expression=*/true);
+ break;
+ }
+
+ ObjCARCReferenceLifetimeType = QualType();
+ }
+
+ return ReferenceTemporary;
+ }
+
llvm::SmallVector<SubobjectAdjustment, 2> Adjustments;
while (true) {
E = E->IgnoreParens();
@@ -298,34 +359,6 @@
if (!ClassDecl->hasTrivialDestructor())
ReferenceTemporaryDtor = ClassDecl->getDestructor();
}
- else if (CGF.getContext().getLangOptions().ObjCAutoRefCount) {
- if (const ValueDecl *InitVD = dyn_cast<ValueDecl>(InitializedDecl)) {
- if (const ReferenceType *RefType
- = InitVD->getType()->getAs<ReferenceType>()) {
- QualType PointeeType = RefType->getPointeeType();
- if (PointeeType->isObjCLifetimeType() &&
- PointeeType.getObjCLifetime() != Qualifiers::OCL_ExplicitNone) {
- // Objective-C++ ARC: We're binding a reference to
- // lifetime-qualified type to a temporary, so we need to extend
- // the lifetime of the temporary with appropriate retain/release/
- // autorelease calls.
- ObjCARCReferenceLifetimeType = PointeeType;
-
- // Create a temporary variable that we can bind the reference to.
- ReferenceTemporary = CreateReferenceTemporary(CGF, PointeeType,
- InitializedDecl);
-
- unsigned Alignment =
- CGF.getContext().getTypeAlignInChars(PointeeType).getQuantity();
- LValue lvalue =
- CGF.MakeAddrLValue(ReferenceTemporary, PointeeType, Alignment);
-
- CGF.EmitScalarInit(E, InitVD, lvalue, false);
- return ReferenceTemporary;
- }
- }
- }
- }
}
RV = CGF.EmitAnyExpr(E, AggSlot);
Modified: cfe/trunk/lib/CodeGen/CGObjC.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/CGObjC.cpp?rev=133620&r1=133619&r2=133620&view=diff
==============================================================================
--- cfe/trunk/lib/CodeGen/CGObjC.cpp (original)
+++ cfe/trunk/lib/CodeGen/CGObjC.cpp Wed Jun 22 11:12:01 2011
@@ -1985,6 +1985,21 @@
CallReleaseForObject(QualType type, llvm::Value *addr, bool precise)
: ObjCReleasingCleanup(type, addr), precise(precise) {}
+ using ObjCReleasingCleanup::Emit;
+ static void Emit(CodeGenFunction &CGF, bool IsForEH,
+ QualType type, llvm::Value *addr, bool precise) {
+ // EHScopeStack::Cleanup objects can never have their destructors called,
+ // so use placement new to construct our temporary object.
+ union {
+ void* align;
+ char data[sizeof(CallReleaseForObject)];
+ };
+
+ CallReleaseForObject *Object
+ = new (&align) CallReleaseForObject(type, addr, precise);
+ Object->Emit(CGF, IsForEH);
+ }
+
void release(CodeGenFunction &CGF, QualType type, llvm::Value *addr) {
llvm::Value *ptr = CGF.Builder.CreateLoad(addr, "tmp");
CGF.EmitARCRelease(ptr, precise);
@@ -2033,6 +2048,21 @@
CallWeakReleaseForObject(QualType type, llvm::Value *addr)
: ObjCReleasingCleanup(type, addr) {}
+ using ObjCReleasingCleanup::Emit;
+ static void Emit(CodeGenFunction &CGF, bool IsForEH,
+ QualType type, llvm::Value *addr) {
+ // EHScopeStack::Cleanup objects can never have their destructors called,
+ // so use placement new to construct our temporary object.
+ union {
+ void* align;
+ char data[sizeof(CallWeakReleaseForObject)];
+ };
+
+ CallWeakReleaseForObject *Object
+ = new (&align) CallWeakReleaseForObject(type, addr);
+ Object->Emit(CGF, IsForEH);
+ }
+
void release(CodeGenFunction &CGF, QualType type, llvm::Value *addr) {
CGF.EmitARCDestroyWeak(addr);
}
@@ -2099,16 +2129,24 @@
void CodeGenFunction::PushARCReleaseCleanup(CleanupKind cleanupKind,
QualType type,
llvm::Value *addr,
- bool precise) {
- EHStack.pushCleanup<CallReleaseForObject>(cleanupKind, type, addr, precise);
+ bool precise,
+ bool forFullExpr) {
+ if (forFullExpr)
+ pushFullExprCleanup<CallReleaseForObject>(cleanupKind, type, addr, precise);
+ else
+ EHStack.pushCleanup<CallReleaseForObject>(cleanupKind, type, addr, precise);
}
/// PushARCWeakReleaseCleanup - Enter a cleanup to perform a weak
/// release on the given object or array of objects.
void CodeGenFunction::PushARCWeakReleaseCleanup(CleanupKind cleanupKind,
QualType type,
- llvm::Value *addr) {
- EHStack.pushCleanup<CallWeakReleaseForObject>(cleanupKind, type, addr);
+ llvm::Value *addr,
+ bool forFullExpr) {
+ if (forFullExpr)
+ pushFullExprCleanup<CallWeakReleaseForObject>(cleanupKind, type, addr);
+ else
+ EHStack.pushCleanup<CallWeakReleaseForObject>(cleanupKind, type, addr);
}
/// PushARCReleaseCleanup - Enter a cleanup to perform a release on a
Modified: cfe/trunk/lib/CodeGen/CodeGenFunction.h
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/CodeGenFunction.h?rev=133620&r1=133619&r2=133620&view=diff
==============================================================================
--- cfe/trunk/lib/CodeGen/CodeGenFunction.h (original)
+++ cfe/trunk/lib/CodeGen/CodeGenFunction.h Wed Jun 22 11:12:01 2011
@@ -223,6 +223,16 @@
}
};
+ template <class T, class A0, class A1, class A2>
+ class UnconditionalCleanup3 : public Cleanup {
+ A0 a0; A1 a1; A2 a2;
+ public:
+ UnconditionalCleanup3(A0 a0, A1 a1, A2 a2) : a0(a0), a1(a1), a2(a2) {}
+ void Emit(CodeGenFunction &CGF, bool IsForEHCleanup) {
+ T::Emit(CGF, IsForEHCleanup, a0, a1, a2);
+ }
+ };
+
/// ConditionalCleanupN stores the saved form of its N parameters,
/// then restores them and performs the cleanup.
template <class T, class A0>
@@ -258,6 +268,27 @@
: a0_saved(a0), a1_saved(a1) {}
};
+ template <class T, class A0, class A1, class A2>
+ class ConditionalCleanup3 : public Cleanup {
+ typedef typename DominatingValue<A0>::saved_type A0_saved;
+ typedef typename DominatingValue<A1>::saved_type A1_saved;
+ typedef typename DominatingValue<A2>::saved_type A2_saved;
+ A0_saved a0_saved;
+ A1_saved a1_saved;
+ A2_saved a2_saved;
+
+ void Emit(CodeGenFunction &CGF, bool IsForEHCleanup) {
+ A0 a0 = DominatingValue<A0>::restore(CGF, a0_saved);
+ A1 a1 = DominatingValue<A1>::restore(CGF, a1_saved);
+ A2 a2 = DominatingValue<A2>::restore(CGF, a2_saved);
+ T::Emit(CGF, IsForEHCleanup, a0, a1, a2);
+ }
+
+ public:
+ ConditionalCleanup3(A0_saved a0, A1_saved a1, A2_saved a2)
+ : a0_saved(a0), a1_saved(a1), a2_saved(a2) {}
+ };
+
private:
// The implementation for this class is in CGException.h and
// CGException.cpp; the definition is here because it's used as a
@@ -697,6 +728,27 @@
initFullExprCleanup();
}
+ /// pushFullExprCleanup - Push a cleanup to be run at the end of the
+ /// current full-expression. Safe against the possibility that
+ /// we're currently inside a conditionally-evaluated expression.
+ template <class T, class A0, class A1, class A2>
+ void pushFullExprCleanup(CleanupKind kind, A0 a0, A1 a1, A2 a2) {
+ // If we're not in a conditional branch, or if none of the
+ // arguments requires saving, then use the unconditional cleanup.
+ if (!isInConditionalBranch()) {
+ typedef EHScopeStack::UnconditionalCleanup3<T, A0, A1, A2> CleanupType;
+ return EHStack.pushCleanup<CleanupType>(kind, a0, a1, a2);
+ }
+
+ typename DominatingValue<A0>::saved_type a0_saved = saveValueInCond(a0);
+ typename DominatingValue<A1>::saved_type a1_saved = saveValueInCond(a1);
+ typename DominatingValue<A2>::saved_type a2_saved = saveValueInCond(a2);
+
+ typedef EHScopeStack::ConditionalCleanup3<T, A0, A1, A2> CleanupType;
+ EHStack.pushCleanup<CleanupType>(kind, a0_saved, a1_saved, a2_saved);
+ initFullExprCleanup();
+ }
+
/// PushDestructorCleanup - Push a cleanup to call the
/// complete-object destructor of an object of the given type at the
/// given address. Does nothing if T is not a C++ class type with a
@@ -2036,9 +2088,10 @@
llvm::Value *EmitARCRetainAutoreleaseScalarExpr(const Expr *expr);
void PushARCReleaseCleanup(CleanupKind kind, QualType type,
- llvm::Value *addr, bool precise);
+ llvm::Value *addr, bool precise,
+ bool forFullExpr = false);
void PushARCWeakReleaseCleanup(CleanupKind kind, QualType type,
- llvm::Value *addr);
+ llvm::Value *addr, bool forFullExpr = false);
void PushARCFieldReleaseCleanup(CleanupKind cleanupKind,
const FieldDecl *Field);
void PushARCFieldWeakReleaseCleanup(CleanupKind cleanupKind,
Modified: cfe/trunk/lib/Sema/SemaInit.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Sema/SemaInit.cpp?rev=133620&r1=133619&r2=133620&view=diff
==============================================================================
--- cfe/trunk/lib/Sema/SemaInit.cpp (original)
+++ cfe/trunk/lib/Sema/SemaInit.cpp Wed Jun 22 11:12:01 2011
@@ -4084,6 +4084,13 @@
Entity.getType().getNonReferenceType(),
CurInit.get(),
Entity.getType()->isLValueReferenceType());
+
+ // If we're binding to an Objective-C object that has lifetime, we
+ // need cleanups.
+ if (S.getLangOptions().ObjCAutoRefCount &&
+ CurInit.get()->getType()->isObjCLifetimeType())
+ S.ExprNeedsCleanups = true;
+
break;
case SK_ExtraneousCopyToTemporary:
Modified: cfe/trunk/test/CodeGenObjCXX/arc-references.mm
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/CodeGenObjCXX/arc-references.mm?rev=133620&r1=133619&r2=133620&view=diff
==============================================================================
--- cfe/trunk/test/CodeGenObjCXX/arc-references.mm (original)
+++ cfe/trunk/test/CodeGenObjCXX/arc-references.mm Wed Jun 22 11:12:01 2011
@@ -1,5 +1,8 @@
// RUN: %clang_cc1 -triple x86_64-apple-darwin10 -emit-llvm -fobjc-nonfragile-abi -fblocks -fobjc-arc -O2 -disable-llvm-optzns -o - %s | FileCheck %s
+ at interface A
+ at end
+
id getObject();
void callee();
@@ -44,6 +47,33 @@
// CHECK-NEXT: ret void
}
+// CHECK: define void @_Z5test4RU8__strongP11objc_object
+void test4(__strong id &x) {
+ // CHECK: call i8* @objc_retain
+ __strong A* const &ar = x;
+ // CHECK: store i32 17, i32*
+ int i = 17;
+ // CHECK: call void @objc_release(
+ // CHECK: ret void
+}
+
+void sink(__strong A* &&);
+
+// CHECK: define void @_Z5test5RU8__strongP11objc_object
+void test5(__strong id &x) {
+ // CHECK: [[OBJ_ID:%[a-zA-Z0-9]+]] = call i8* @objc_retain
+ // CHECK-NEXT: [[OBJ_A:%[a-zA-Z0-9]+]] = bitcast i8* [[OBJ_ID]] to [[A:%[a-zA-Z0-9]+]]*
+ // CHECK-NEXT: store [[A]]* [[OBJ_A]], [[A]]** [[REFTMP:%[a-zA-Z0-9]+]]
+ // CHECK-NEXT: call void @_Z4sinkOU8__strongP1A
+ sink(x);
+ // CHECK-NEXT: [[OBJ_A:%[a-zA-Z0-9]+]] = load [[A]]** [[REFTMP]]
+ // CHECK-NEXT: [[OBJ_ID:%[a-zA-Z0-9]+]] = bitcast [[A]]* [[OBJ_A]] to i8*
+ // CHECK-NEXT: call void @objc_release
+ // CHECK-NEXT: store i32 17, i32
+ int i = 17;
+ // CHECK-NEXT: ret void
+}
+
// CHECK: define internal void @__cxx_global_var_init(
// CHECK: call i8* @_Z9getObjectv
// CHECK-NEXT: call i8* @objc_retainAutoreleasedReturnValue
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