Fixed a bug in generation of the new write-barriers when

array syntax is used to derefernce and assign to ivar pointee.

llvm-svn: 82183

clang/lib/CodeGen/CGExpr.cpp

@@ -697,6 +697,7 @@ void setObjCGCLValueClass(const ASTContext &Ctx, const Expr *E, LValue &LV) {
   
   if (isa<ObjCIvarRefExpr>(E)) {
     LV.SetObjCIvar(LV, true);
+    LV.SetObjCIvarArray(LV, E->getType()->isArrayType());
     return;
   }
   if (const DeclRefExpr *Exp = dyn_cast<DeclRefExpr>(E)) {
@@ -714,10 +715,19 @@ void setObjCGCLValueClass(const ASTContext &Ctx, const Expr *E, LValue &LV) {
     setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV);
   else if (const CStyleCastExpr *Exp = dyn_cast<CStyleCastExpr>(E))
     setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV);
-  else if (const ArraySubscriptExpr *Exp = dyn_cast<ArraySubscriptExpr>(E))
+  else if (const ArraySubscriptExpr *Exp = dyn_cast<ArraySubscriptExpr>(E)) {
     setObjCGCLValueClass(Ctx, Exp->getBase(), LV);
+    if (LV.isObjCIvar() && !LV.isObjCIvarArray()) {
+      // Using array syntax to assigning to what an ivar points to is not 
+      // same as assigning to the ivar itself. {id *Names;} Names[i] = 0;
+      LV.SetObjCIvar(LV, false); 
+    }
+  }
   else if (const MemberExpr *Exp = dyn_cast<MemberExpr>(E)) {
     setObjCGCLValueClass(Ctx, Exp->getBase(), LV);
+    // We don't know if member is an 'ivar', but this flag is looked at
+    // only in the context of LV.isObjCIvar().
+    LV.SetObjCIvarArray(LV, E->getType()->isArrayType());
   }
 }
 

clang/lib/CodeGen/CGValue.h

@@ -152,6 +152,9 @@ class LValue {
 
   // objective-c's ivar
   bool Ivar:1;
+  
+  // objective-c's ivar is an array
+  bool IvarArray:1;
 
   // LValue is non-gc'able for any reason, including being a parameter or local
   // variable.
@@ -173,7 +176,7 @@ private:
     // FIXME: Convenient place to set objc flags to 0. This should really be
     // done in a user-defined constructor instead.
     R.ObjCType = None;
-    R.Ivar = R.NonGC = R.GlobalObjCRef = false;
+    R.Ivar = R.IvarArray = R.NonGC = R.GlobalObjCRef = false;
   }
 
 public:
@@ -192,6 +195,7 @@ public:
   }
 
   bool isObjCIvar() const { return Ivar; }
+  bool isObjCIvarArray() const { return IvarArray; }
   bool isNonGC () const { return NonGC; }
   bool isGlobalObjCRef() const { return GlobalObjCRef; }
   bool isObjCWeak() const { return ObjCType == Weak; }
@@ -202,7 +206,9 @@ public:
   static void SetObjCIvar(LValue& R, bool iValue) {
     R.Ivar = iValue;
   }
-
+  static void SetObjCIvarArray(LValue& R, bool iValue) {
+    R.IvarArray = iValue;
+  }
   static void SetGlobalObjCRef(LValue& R, bool iValue) {
     R.GlobalObjCRef = iValue;
   }

clang/test/CodeGenObjC/objc2-write-barrier-2.m

@@ -1,7 +1,7 @@
 // RUN: clang-cc -fnext-runtime -fobjc-gc -fobjc-newgc-api -emit-llvm -o %t %s &&
 // RUN: grep -F '@objc_assign_global' %t  | count 7 &&
-// RUN: grep -F '@objc_assign_ivar' %t  | count 4 &&
-// RUN: grep -F '@objc_assign_strongCast' %t  | count 4 &&
+// RUN: grep -F '@objc_assign_ivar' %t  | count 5 &&
+// RUN: grep -F '@objc_assign_strongCast' %t  | count 8 &&
 // RUN: true
 
 extern id **somefunc(void);
@@ -50,3 +50,31 @@ void funct2(AStruct *aptr) {
     *ppptr = somefunc2(); 
 }
 
+typedef const struct __CFString * CFStringRef;
+@interface DSATextSearch {
+__strong CFStringRef *_documentNames;
+  struct {
+    id *innerNames;
+    struct {
+      id *nestedDeeperNames; 
+      struct I {
+         id *is1;
+         id is2[5];
+      } arrI [3];
+    } inner_most;
+  } inner;
+
+}
+- filter;
+@end
+@implementation DSATextSearch
+- filter {
+  int filteredPos = 0;
+  _documentNames[filteredPos] = 0; // storing into an element of array ivar. objc_assign_strongCast is needed.
+  inner.innerNames[filteredPos] = 0;
+  inner.inner_most.nestedDeeperNames[filteredPos] = 0;
+  inner.inner_most.arrI[3].is1[5] = 0;
+  inner.inner_most.arrI[3].is2[5] = 0;
+}
+@end
+