r179254 - Drop ObjCIndirectCopyRestoreExprs during template instantiation.

[John McCall]

Author: rjmccall
Date: Wed Apr 10 21:14:26 2013
New Revision: 179254

URL: http://llvm.org/viewvc/llvm-project?rev=179254&view=rev
Log:
Drop ObjCIndirectCopyRestoreExprs during template instantiation.

It's a kind of implicit conversion, which we generally drop, but
more importantly it's got very specific placement requirements.

rdar://13617051

Modified:
    cfe/trunk/lib/Sema/TreeTransform.h
    cfe/trunk/test/CodeGenObjCXX/arc.mm

Modified: cfe/trunk/lib/Sema/TreeTransform.h
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Sema/TreeTransform.h?rev=179254&r1=179253&r2=179254&view=diff
==============================================================================
--- cfe/trunk/lib/Sema/TreeTransform.h (original)
+++ cfe/trunk/lib/Sema/TreeTransform.h Wed Apr 10 21:14:26 2013
@@ -8608,16 +8608,11 @@ TreeTransform<Derived>::TransformObjCEnc
 template<typename Derived>
 ExprResult TreeTransform<Derived>::
 TransformObjCIndirectCopyRestoreExpr(ObjCIndirectCopyRestoreExpr *E) {
-  ExprResult result = getDerived().TransformExpr(E->getSubExpr());
-  if (result.isInvalid()) return ExprError();
-  Expr *subExpr = result.take();
-
-  if (!getDerived().AlwaysRebuild() &&
-      subExpr == E->getSubExpr())
-    return SemaRef.Owned(E);
-
-  return SemaRef.Owned(new(SemaRef.Context)
-      ObjCIndirectCopyRestoreExpr(subExpr, E->getType(), E->shouldCopy()));
+  // This is a kind of implicit conversion, and it needs to get dropped
+  // and recomputed for the same general reasons that ImplicitCastExprs
+  // do, as well a more specific one: this expression is only valid when
+  // it appears *immediately* as an argument expression.
+  return getDerived().TransformExpr(E->getSubExpr());
 }
 
 template<typename Derived>

Modified: cfe/trunk/test/CodeGenObjCXX/arc.mm
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/CodeGenObjCXX/arc.mm?rev=179254&r1=179253&r2=179254&view=diff
==============================================================================
--- cfe/trunk/test/CodeGenObjCXX/arc.mm (original)
+++ cfe/trunk/test/CodeGenObjCXX/arc.mm Wed Apr 10 21:14:26 2013
@@ -275,3 +275,25 @@ id Test39::bar() { return 0; }
 // CHECK:    define i8* @_ZThn8_N6Test393barEv(
 // CHECK:      call i8* @_ZN6Test393barEv(
 // CHECK-NEXT: ret i8*
+
+// rdar://13617051
+// Just a basic sanity-check that IR-gen still works after instantiating
+// a non-dependent message send that requires writeback.
+ at interface Test40
++ (void) foo:(id *)errorPtr;
+ at end
+template <class T> void test40_helper() {
+  id x;
+  [Test40 foo: &x];
+};
+template void test40_helper<int>();
+// CHECK:    define weak_odr void @_Z13test40_helperIiEvv()
+// CHECK:      [[X:%.*]] = alloca i8*
+// CHECK-NEXT: [[TEMP:%.*]] = alloca i8*
+// CHECK-NEXT: store i8* null, i8** [[X]]
+// CHECK:      [[T0:%.*]] = load i8** [[X]]
+// CHECK-NEXT: store i8* [[T0]], i8** [[TEMP]]
+// CHECK:      @objc_msgSend
+// CHECK-NEXT: [[T0:%.*]] = load i8** [[TEMP]]
+// CHECK-NEXT: call i8* @objc_retain(i8* [[T0]])
+