[Objective-C] Fix non-determinism in clang

Summary: Iteration of the unordered Ivars causes objc-modern-metadata-visibility.mm (uncovered by reverse iterating SmallPtrSet).

Reviewers: dblaikie, davide, rsmith

Reviewed By: dblaikie

Subscribers: cfe-commits, llvm-commits

Differential Revision: https://reviews.llvm.org/D34860

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@307296 91177308-0d34-0410-b5e6-96231b3b80d8

Author: Mandeep Singh Grang

lib/Frontend/Rewrite/RewriteModernObjC.cpp

@@ -146,7 +146,7 @@ namespace {
 
     llvm::DenseMap<BlockExpr *, std::string> RewrittenBlockExprs;
     llvm::DenseMap<ObjCInterfaceDecl *, 
-                    llvm::SmallPtrSet<ObjCIvarDecl *, 8> > ReferencedIvars;
+                    llvm::SmallSetVector<ObjCIvarDecl *, 8> > ReferencedIvars;
 
     // ivar bitfield grouping containers
     llvm::DenseSet<const ObjCInterfaceDecl *> ObjCInterefaceHasBitfieldGroups;
@@ -1013,7 +1013,7 @@ void RewriteModernObjC::RewritePropertyImplDecl(ObjCPropertyImplDecl *PID,
     Setr = "\nextern \"C\" __declspec(dllimport) "
     "void objc_setProperty (id, SEL, long, id, bool, bool);\n";
   }
-  
+
   RewriteObjCMethodDecl(OID->getContainingInterface(), 
                         PD->getSetterMethodDecl(), Setr);
   Setr += "{ ";
@@ -3965,10 +3965,11 @@ void RewriteModernObjC::RewriteIvarOffsetSymbols(ObjCInterfaceDecl *CDecl,
                                                   std::string &Result) {
   // write out ivar offset symbols which have been referenced in an ivar
   // access expression.
-  llvm::SmallPtrSet<ObjCIvarDecl *, 8> Ivars = ReferencedIvars[CDecl];
+  llvm::SmallSetVector<ObjCIvarDecl *, 8> Ivars = ReferencedIvars[CDecl];
+
   if (Ivars.empty())
     return;
-  
+
   llvm::DenseSet<std::pair<const ObjCInterfaceDecl*, unsigned> > GroupSymbolOutput;
   for (ObjCIvarDecl *IvarDecl : Ivars) {
     const ObjCInterfaceDecl *IDecl = IvarDecl->getContainingInterface();

test/Rewriter/objc-modern-metadata-visibility2.mm

@@ -0,0 +1,45 @@
+// REQUIRES: abi-breaking-checks
+// NOTE: This test has been split from objc-modern-metadata-visibility.mm in
+// order to test with -reverse-iterate as this flag is only present with
+// ABI_BREAKING_CHECKS.
+
+// RUN: %clang_cc1 -E %s -o %t.mm -mllvm -reverse-iterate
+// RUN: %clang_cc1 -x objective-c++ -fblocks -fms-extensions -rewrite-objc %t.mm -mllvm -reverse-iterate -o - | FileCheck %s
+// rdar://11144048
+
+@class NSString;
+
+@interface NSObject {
+    Class isa;
+}
+@end
+
+@interface Sub : NSObject {
+    int subIvar;
+    NSString *nsstring;
+@private
+    id PrivateIvar;
+}
+@end
+
+@implementation Sub
+- (id) MyNSString { return subIvar ? PrivateIvar : nsstring; }
+@end
+
+@interface NSString @end
+@implementation NSString @end
+
+// CHECK: __declspec(allocate(".objc_ivar$B")) extern "C" __declspec(dllimport) unsigned long OBJC_IVAR_$_Sub$subIvar;
+// CHECK: __declspec(allocate(".objc_ivar$B")) extern "C" unsigned long OBJC_IVAR_$_Sub$PrivateIvar;
+// CHECK: __declspec(allocate(".objc_ivar$B")) extern "C" __declspec(dllimport) unsigned long OBJC_IVAR_$_Sub$nsstring;
+// CHECK: #pragma warning(disable:4273)
+// CHECK: __declspec(allocate(".objc_ivar$B")) extern "C" __declspec(dllexport) unsigned long int OBJC_IVAR_$_Sub$subIvar
+// CHECK: __declspec(allocate(".objc_ivar$B")) extern "C" __declspec(dllexport) unsigned long int OBJC_IVAR_$_Sub$nsstring
+// CHECK: __declspec(allocate(".objc_ivar$B")) extern "C" unsigned long int OBJC_IVAR_$_Sub$PrivateIvar
+// CHECK: extern "C" __declspec(dllimport) struct _class_t OBJC_METACLASS_$_NSObject;
+// CHECK: extern "C" __declspec(dllexport) struct _class_t OBJC_METACLASS_$_Sub
+// CHECK: extern "C" __declspec(dllimport) struct _class_t OBJC_CLASS_$_NSObject;
+// CHECK: extern "C" __declspec(dllexport) struct _class_t OBJC_CLASS_$_Sub
+// CHECK: extern "C" __declspec(dllexport) struct _class_t OBJC_CLASS_$_NSString;
+// CHECK: extern "C" __declspec(dllexport) struct _class_t OBJC_METACLASS_$_NSString
+// CHECK: extern "C" __declspec(dllexport) struct _class_t OBJC_CLASS_$_NSString