[cfe-commits] r135747 - in /cfe/trunk: lib/CodeGen/CGObjC.cpp test/CodeGenObjC/arc.m

[John McCall]

Author: rjmccall
Date: Fri Jul 22 00:23:13 2011
New Revision: 135747

URL: http://llvm.org/viewvc/llvm-project?rev=135747&view=rev
Log:
In ARC, non-atomic getters do not need to retain and autorelease
their loaded values, although it still worth doing this for __weak
properties to get the autoreleased-return-value optimization.


Modified:
    cfe/trunk/lib/CodeGen/CGObjC.cpp
    cfe/trunk/test/CodeGenObjC/arc.m

Modified: cfe/trunk/lib/CodeGen/CGObjC.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/CGObjC.cpp?rev=135747&r1=135746&r2=135747&view=diff
==============================================================================
--- cfe/trunk/lib/CodeGen/CGObjC.cpp (original)
+++ cfe/trunk/lib/CodeGen/CGObjC.cpp Fri Jul 22 00:23:13 2011
@@ -465,27 +465,30 @@
           EmitAggregateCopy(ReturnValue, LV.getAddress(), IVART);
         }
       }
-    } 
-    else {
-        LValue LV = EmitLValueForIvar(TypeOfSelfObject(), LoadObjCSelf(), 
-                                      Ivar, 0);
-        QualType propType = PD->getType();
-
-        llvm::Value *value;
-        if (propType->isReferenceType()) {
-          value = LV.getAddress();
-        } else {
-          // In ARC, we want to emit this retained.
-          if (getLangOptions().ObjCAutoRefCount &&
-              PD->getType()->isObjCRetainableType())
-            value = emitARCRetainLoadOfScalar(*this, LV, IVART);
-          else
-            value = EmitLoadOfLValue(LV).getScalarVal();
+    } else {
+      LValue LV = EmitLValueForIvar(TypeOfSelfObject(), LoadObjCSelf(), 
+                                    Ivar, 0);
+      QualType propType = PD->getType();
+
+      llvm::Value *value;
+      if (propType->isReferenceType()) {
+        value = LV.getAddress();
+      } else {
+        // We want to load and autoreleaseReturnValue ARC __weak ivars.
+        if (LV.getQuals().getObjCLifetime() == Qualifiers::OCL_Weak) {
+          value = emitARCRetainLoadOfScalar(*this, LV, IVART);
 
-          value = Builder.CreateBitCast(value, ConvertType(propType));
+        // Otherwise we want to do a simple load, suppressing the
+        // final autorelease.
+        } else {
+          value = EmitLoadOfLValue(LV).getScalarVal();
+          AutoreleaseResult = false;
         }
 
-        EmitReturnOfRValue(RValue::get(value), propType);
+        value = Builder.CreateBitCast(value, ConvertType(propType));
+      }
+      
+      EmitReturnOfRValue(RValue::get(value), propType);
     }
   }
 

Modified: cfe/trunk/test/CodeGenObjC/arc.m
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/CodeGenObjC/arc.m?rev=135747&r1=135746&r2=135747&view=diff
==============================================================================
--- cfe/trunk/test/CodeGenObjC/arc.m (original)
+++ cfe/trunk/test/CodeGenObjC/arc.m Fri Jul 22 00:23:13 2011
@@ -1578,3 +1578,41 @@
   // CHECK-NEXT: call void @objc_release(i8* [[T0]])
   // CHECK-NEXT: ret void
 }
+
+// rdar://problem/9784964
+ at interface Test57
+ at property (nonatomic, strong) id strong;
+ at property (nonatomic, weak) id weak;
+ at property (nonatomic, unsafe_unretained) id unsafe;
+ at end
+ at implementation Test57
+ at synthesize strong, weak, unsafe;
+ at end
+// CHECK: define internal i8* @"\01-[Test57 strong]"(
+// CHECK:      [[T0:%.*]] = load [[TEST57:%.*]]** {{%.*}}
+// CHECK-NEXT: [[T1:%.*]] = load i64* @"OBJC_IVAR_$_Test57.strong"
+// CHECK-NEXT: [[T2:%.*]] = bitcast [[TEST57]]* [[T0]] to i8*
+// CHECK-NEXT: [[T3:%.*]] = getelementptr inbounds i8* [[T2]], i64 [[T1]]
+// CHECK-NEXT: [[T4:%.*]] = bitcast i8* [[T3]] to i8**
+// CHECK-NEXT: [[T5:%.*]] = load i8** [[T4]]
+// CHECK-NEXT: ret i8* [[T5]]
+
+// CHECK: define internal i8* @"\01-[Test57 weak]"(
+// CHECK:      [[T0:%.*]] = load [[TEST57]]** {{%.*}}
+// CHECK-NEXT: [[T1:%.*]] = load i64* @"OBJC_IVAR_$_Test57.weak"
+// CHECK-NEXT: [[T2:%.*]] = bitcast [[TEST57]]* [[T0]] to i8*
+// CHECK-NEXT: [[T3:%.*]] = getelementptr inbounds i8* [[T2]], i64 [[T1]]
+// CHECK-NEXT: [[T4:%.*]] = bitcast i8* [[T3]] to i8**
+// CHECK-NEXT: [[T5:%.*]] = call i8* @objc_loadWeakRetained(i8** [[T4]])
+// CHECK-NEXT: [[T6:%.*]] = call i8* @objc_autoreleaseReturnValue(i8* [[T5]])
+// CHECK-NEXT: ret i8* [[T6]]
+
+// CHECK: define internal i8* @"\01-[Test57 unsafe]"(
+// CHECK:      [[T0:%.*]] = load [[TEST57]]** {{%.*}}
+// CHECK-NEXT: [[T1:%.*]] = load i64* @"OBJC_IVAR_$_Test57.unsafe"
+// CHECK-NEXT: [[T2:%.*]] = bitcast [[TEST57]]* [[T0]] to i8*
+// CHECK-NEXT: [[T3:%.*]] = getelementptr inbounds i8* [[T2]], i64 [[T1]]
+// CHECK-NEXT: [[T4:%.*]] = bitcast i8* [[T3]] to i8**
+// CHECK-NEXT: [[T5:%.*]] = load i8** [[T4]]
+// CHECK-NEXT: ret i8* [[T5]]
+