From b9966bd81878c6627d702368d6c4a8bc62bc01ac Mon Sep 17 00:00:00 2001
From: Fariborz Jahanian <fjahanian@apple.com>
Date: Wed, 10 Oct 2012 23:11:18 +0000
Subject: [PATCH] objective-C IRgen: When sending a method to 'super' in a
 category class method, don't read 'isa' pointer. Instead, save the desired
 OBJC_METACLASS_$_ClassName in __DATA,__objc_superrefs and read that without
 reading any isa pointers. // rdar://12459358

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@165674 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/CodeGen/CGObjCMac.cpp                    | 11 ++-----
 test/CodeGenObjC/category-super-class-meth.m | 32 +++++++++++++-------
 2 files changed, 23 insertions(+), 20 deletions(-)

diff --git a/lib/CodeGen/CGObjCMac.cpp b/lib/CodeGen/CGObjCMac.cpp
index 4e4879921a..22ea521f8e 100644
--- a/lib/CodeGen/CGObjCMac.cpp
+++ b/lib/CodeGen/CGObjCMac.cpp
@@ -6083,16 +6083,9 @@ CGObjCNonFragileABIMac::GenerateMessageSendSuper(CodeGen::CodeGenFunction &CGF,
 
   // If this is a class message the metaclass is passed as the target.
   llvm::Value *Target;
-  if (IsClassMessage) {
-    if (isCategoryImpl) {
-      // Message sent to "super' in a class method defined in
-      // a category implementation.
-      Target = EmitClassRef(CGF.Builder, Class);
-      Target = CGF.Builder.CreateStructGEP(Target, 0);
-      Target = CGF.Builder.CreateLoad(Target);
-    } else
+  if (IsClassMessage)
       Target = EmitMetaClassRef(CGF.Builder, Class);
-  } else
+  else
     Target = EmitSuperClassRef(CGF.Builder, Class);
 
   // FIXME: We shouldn't need to do this cast, rectify the ASTContext and
diff --git a/test/CodeGenObjC/category-super-class-meth.m b/test/CodeGenObjC/category-super-class-meth.m
index 6f02aff96d..5ba7adff8b 100644
--- a/test/CodeGenObjC/category-super-class-meth.m
+++ b/test/CodeGenObjC/category-super-class-meth.m
@@ -1,19 +1,29 @@
-// RUN: %clang_cc1 -emit-llvm -o %t %s
-
-@interface BASE
-+ (int) BaseMeth;
+// RUN: %clang_cc1 %s -emit-llvm -triple x86_64-apple-darwin -o - | FileCheck %s
+// rdar://12459358
+@interface NSObject 
+-(id)copy;
++(id)copy;
 @end
 
-@interface Child: BASE
-@end
+@interface Sub1 : NSObject @end
 
-@interface Child (Categ)
-+ (int) flushCache2;
+@implementation Sub1
+-(id)copy { return [super copy]; }  // ok: instance method in class
++(id)copy { return [super copy]; }  // ok: class method in class
 @end
 
-@implementation Child  @end
+@interface Sub2 : NSObject @end
+
+@interface Sub2 (Category) @end
 
-@implementation Child (Categ)
-+ (int) flushCache2 { [super BaseMeth]; }
+@implementation Sub2 (Category)
+-(id)copy { return [super copy]; }  // ok: instance method in category
++(id)copy { return [super copy]; }  // BAD: class method in category
 @end
 
+// CHECK: define internal i8* @"\01+[Sub2(Category) copy]
+// CHECK: [[ONE:%.*]] = load %struct._class_t** @"\01L_OBJC_CLASSLIST_SUP_REFS_$_3"
+// CHECK: [[TWO:%.*]] = bitcast %struct._class_t* [[ONE]] to i8*
+// CHECK: [[THREE:%.*]] = getelementptr inbounds %struct._objc_super* [[OBJC_SUPER:%.*]], i32 0, i32 1
+// CHECK: store i8* [[TWO]], i8** [[THREE]]
+// CHECK: [[FOUR:%.*]] = load i8** @"\01L_OBJC_SELECTOR_REFERENCES_"
-- 
2.40.0