Fixes an IRgen bug where __block variable is
referenced in the block-literal initializer
of that variable. // rdar://8893785
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@124332 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/CGDecl.cpp b/lib/CodeGen/CGDecl.cpp
index 8270e84..f12be98 100644
--- a/lib/CodeGen/CGDecl.cpp
+++ b/lib/CodeGen/CGDecl.cpp
@@ -305,6 +305,15 @@
return ByRefValueInfo.find(VD)->second.second;
}
+llvm::Value *CodeGenFunction::BuildBlockByrefAddress(llvm::Value *BaseAddr,
+ const VarDecl *V) {
+ llvm::Value *Loc = Builder.CreateStructGEP(BaseAddr, 1, "forwarding");
+ Loc = Builder.CreateLoad(Loc);
+ Loc = Builder.CreateStructGEP(Loc, getByRefValueLLVMField(V),
+ V->getNameAsString());
+ return Loc;
+}
+
/// BuildByRefType - This routine changes a __block variable declared as T x
/// into:
///
@@ -795,9 +804,6 @@
SpecialInit(*this, D, DeclPtr);
} else if (Init) {
llvm::Value *Loc = DeclPtr;
- if (isByRef)
- Loc = Builder.CreateStructGEP(DeclPtr, getByRefValueLLVMField(&D),
- D.getNameAsString());
bool isVolatile = getContext().getCanonicalType(Ty).isVolatileQualified();
@@ -844,13 +850,31 @@
}
} else if (Ty->isReferenceType()) {
RValue RV = EmitReferenceBindingToExpr(Init, &D);
+ if (isByRef)
+ Loc = Builder.CreateStructGEP(DeclPtr, getByRefValueLLVMField(&D),
+ D.getNameAsString());
EmitStoreOfScalar(RV.getScalarVal(), Loc, false, Alignment, Ty);
} else if (!hasAggregateLLVMType(Init->getType())) {
llvm::Value *V = EmitScalarExpr(Init);
+ if (isByRef) {
+ // When RHS has side-effect, must go through "forwarding' field
+ // to get to the address of the __block variable descriptor.
+ if (Init->HasSideEffects(getContext()))
+ Loc = BuildBlockByrefAddress(DeclPtr, &D);
+ else
+ Loc = Builder.CreateStructGEP(DeclPtr, getByRefValueLLVMField(&D),
+ D.getNameAsString());
+ }
EmitStoreOfScalar(V, Loc, isVolatile, Alignment, Ty);
} else if (Init->getType()->isAnyComplexType()) {
+ if (isByRef)
+ Loc = Builder.CreateStructGEP(DeclPtr, getByRefValueLLVMField(&D),
+ D.getNameAsString());
EmitComplexExprIntoAddr(Init, Loc, isVolatile);
} else {
+ if (isByRef)
+ Loc = Builder.CreateStructGEP(DeclPtr, getByRefValueLLVMField(&D),
+ D.getNameAsString());
EmitAggExpr(Init, AggValueSlot::forAddr(Loc, isVolatile, true, false));
}
}
diff --git a/lib/CodeGen/CGExpr.cpp b/lib/CodeGen/CGExpr.cpp
index afc1e07..ca80d3d 100644
--- a/lib/CodeGen/CGExpr.cpp
+++ b/lib/CodeGen/CGExpr.cpp
@@ -1164,12 +1164,9 @@
V = CGM.getStaticLocalDeclAddress(VD);
assert(V && "DeclRefExpr not entered in LocalDeclMap?");
- if (VD->hasAttr<BlocksAttr>()) {
- V = Builder.CreateStructGEP(V, 1, "forwarding");
- V = Builder.CreateLoad(V);
- V = Builder.CreateStructGEP(V, getByRefValueLLVMField(VD),
- VD->getNameAsString());
- }
+ if (VD->hasAttr<BlocksAttr>())
+ V = BuildBlockByrefAddress(V, VD);
+
if (VD->getType()->isReferenceType())
V = Builder.CreateLoad(V, "tmp");
diff --git a/lib/CodeGen/CodeGenFunction.h b/lib/CodeGen/CodeGenFunction.h
index dcd6173..834a1cf 100644
--- a/lib/CodeGen/CodeGenFunction.h
+++ b/lib/CodeGen/CodeGenFunction.h
@@ -811,7 +811,11 @@
/// getByrefValueFieldNumber - Given a declaration, returns the LLVM field
/// number that holds the value.
unsigned getByRefValueLLVMField(const ValueDecl *VD) const;
-
+
+ /// BuildBlockByrefAddress - Computes address location of the
+ /// variable which is declared as __block.
+ llvm::Value *BuildBlockByrefAddress(llvm::Value *BaseAddr,
+ const VarDecl *V);
private:
CGDebugInfo *DebugInfo;
diff --git a/test/CodeGenObjC/block-6.m b/test/CodeGenObjC/block-6.m
new file mode 100644
index 0000000..3720a87
--- /dev/null
+++ b/test/CodeGenObjC/block-6.m
@@ -0,0 +1,12 @@
+// RUN: %clang_cc1 %s -emit-llvm -o - -fblocks -triple x86_64-apple-darwin10 | FileCheck %s
+// rdar://8893785
+
+void MYFUNC() {
+// CHECK: [[T1:%.*]] = bitcast i8* ()*
+// CHECK-NEXT: [[FORWARDING:%.*]] = getelementptr inbounds [[N_T:%.*]]* [[N:%.*]], i32 0, i32 1
+// CHECK-NEXT: [[T0:%.*]] = load [[N_T]]** [[FORWARDING]]
+// CHECK-NEXT: [[OBSERVER:%.*]] = getelementptr inbounds [[N_T]]* [[T0]], i32 0, i32 6
+// CHECK-NEXT: store i8* [[T1]], i8** [[OBSERVER]]
+ __block id observer = ^{ return observer; };
+}
+