From: Fariborz Jahanian <fjahanian@apple.com>
Date: Fri, 5 Feb 2010 19:18:30 +0000 (+0000)
Subject: Fix a code gen bug accessing 'isa' field via a message call
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=5ed676c90c839c89093b605d76c7e581ab69ebb8;p=clang

Fix a code gen bug accessing 'isa' field via a message call
(Fixes radar 7609722).


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@95406 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/CodeGen/CGExprScalar.cpp b/lib/CodeGen/CGExprScalar.cpp
index f58d6e871b..cb3fb61cf3 100644
--- a/lib/CodeGen/CGExprScalar.cpp
+++ b/lib/CodeGen/CGExprScalar.cpp
@@ -1880,14 +1880,23 @@ LValue CodeGenFunction::EmitObjCIsaExpr(const ObjCIsaExpr *E) {
   llvm::Value *V;
   // object->isa or (*object).isa
   // Generate code as for: *(Class*)object
+  // build Class* type
+  const llvm::Type *ClassPtrTy = ConvertType(E->getType());
+
   Expr *BaseExpr = E->getBase();
-  if (E->isArrow())
-    V = ScalarExprEmitter(*this).EmitLoadOfLValue(BaseExpr);
-  else
-    V  = EmitLValue(BaseExpr).getAddress();
+  if (BaseExpr->isLvalue(getContext()) != Expr::LV_Valid) {
+    V = CreateTempAlloca(ClassPtrTy, "resval");
+    llvm::Value *Src = EmitScalarExpr(BaseExpr);
+    Builder.CreateStore(Src, V);
+  }
+  else {
+      if (E->isArrow())
+        V = ScalarExprEmitter(*this).EmitLoadOfLValue(BaseExpr);
+      else
+        V  = EmitLValue(BaseExpr).getAddress();
+  }
   
   // build Class* type
-  const llvm::Type *ClassPtrTy = ConvertType(E->getType());
   ClassPtrTy = ClassPtrTy->getPointerTo();
   V = Builder.CreateBitCast(V, ClassPtrTy);
   LValue LV = LValue::MakeAddr(V, MakeQualifiers(E->getType()));
diff --git a/test/CodeGenObjC/id-isa-codegen.m b/test/CodeGenObjC/id-isa-codegen.m
index 89e9922090..3179e11b7f 100644
--- a/test/CodeGenObjC/id-isa-codegen.m
+++ b/test/CodeGenObjC/id-isa-codegen.m
@@ -34,3 +34,17 @@ Class Test(const void *inObject1) {
    return ((id)inObject1)->isa;
   return (id)0;
 }
+
+// rdar 7609722
+@interface Foo { 
+@public 
+  id isa; 
+} 
++(id)method;
+@end
+
+id Test2() {
+    if([Foo method]->isa)
+      return (*[Foo method]).isa;
+    return [Foo method]->isa;
+}