add support for usage of cast to union thing with static vars
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@62387 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/CGExprConstant.cpp b/lib/CodeGen/CGExprConstant.cpp
index 4187552..72674f7 100644
--- a/lib/CodeGen/CGExprConstant.cpp
+++ b/lib/CodeGen/CGExprConstant.cpp
@@ -61,6 +61,12 @@
}
llvm::Constant *VisitCastExpr(CastExpr* E) {
+ // GCC cast to union extension
+ if (E->getType()->isUnionType()) {
+ const llvm::Type *Ty = ConvertType(E->getType());
+ return EmitUnion(CGM.EmitConstantExpr(E->getSubExpr(), CGF), Ty);
+ }
+
llvm::Constant *C = Visit(E->getSubExpr());
return EmitConversion(C, E->getSubExpr()->getType(), E->getType());
@@ -217,6 +223,27 @@
return llvm::ConstantStruct::get(SType, Elts);
}
+ llvm::Constant *EmitUnion(llvm::Constant *C, const llvm::Type *Ty) {
+ // Build a struct with the union sub-element as the first member,
+ // and padded to the appropriate size
+ std::vector<llvm::Constant*> Elts;
+ std::vector<const llvm::Type*> Types;
+ Elts.push_back(C);
+ Types.push_back(C->getType());
+ unsigned CurSize = CGM.getTargetData().getTypeStoreSize(C->getType());
+ unsigned TotalSize = CGM.getTargetData().getTypeStoreSize(Ty);
+ while (CurSize < TotalSize) {
+ Elts.push_back(llvm::Constant::getNullValue(llvm::Type::Int8Ty));
+ Types.push_back(llvm::Type::Int8Ty);
+ CurSize++;
+ }
+
+ // This always generates a packed struct
+ // FIXME: Try to generate an unpacked struct when we can
+ llvm::StructType* STy = llvm::StructType::get(Types, true);
+ return llvm::ConstantStruct::get(STy, Elts);
+ }
+
llvm::Constant *EmitUnionInitialization(InitListExpr *ILE) {
RecordDecl *RD = ILE->getType()->getAsRecordType()->getDecl();
const llvm::Type *Ty = ConvertType(ILE->getType());
@@ -248,26 +275,7 @@
return llvm::ConstantArray::get(RetTy, Elts);
}
- llvm::Constant *C = CGM.EmitConstantExpr(ILE->getInit(0), CGF);
-
- // Build a struct with the union sub-element as the first member,
- // and padded to the appropriate size
- std::vector<llvm::Constant*> Elts;
- std::vector<const llvm::Type*> Types;
- Elts.push_back(C);
- Types.push_back(C->getType());
- unsigned CurSize = CGM.getTargetData().getTypeStoreSize(C->getType());
- unsigned TotalSize = CGM.getTargetData().getTypeStoreSize(Ty);
- while (CurSize < TotalSize) {
- Elts.push_back(llvm::Constant::getNullValue(llvm::Type::Int8Ty));
- Types.push_back(llvm::Type::Int8Ty);
- CurSize++;
- }
-
- // This always generates a packed struct
- // FIXME: Try to generate an unpacked struct when we can
- llvm::StructType* STy = llvm::StructType::get(Types, true);
- return llvm::ConstantStruct::get(STy, Elts);
+ return EmitUnion(CGM.EmitConstantExpr(ILE->getInit(0), CGF), Ty);
}
llvm::Constant *EmitVectorInitialization(InitListExpr *ILE) {