Add info to ObjCPropertyRefExpr to indicate whether the dot syntax property

reference is going to message the setter, the getter, or both.

Having this info on the ObjCPropertyRefExpr node makes it easier for AST
clients (like libclang) to reason about the meaning of the property reference.

[AST/Sema]
-Use 2 bits (with a PointerIntPair) in ObjCPropertyRefExpr to record the above info
-Have ObjCPropertyOpBuilder set the info appropriately.

[libclang]
-When there is an implicit property reference (property syntax using methods)
have clang_getCursorReferenced return a cursor for the method. If the property
reference is going to result in messaging both the getter and the setter choose
to return a cursor for the setter because it is less obvious from source inspection
that the setter is getting called.

The general idea has the seal of approval by John.

rdar://11151621

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@153709 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 11 insertions, 2 deletions

diff --git a/tools/libclang/CIndex.cpp b/tools/libclang/CIndex.cpp
index 972beaf9e7..2a05b1b6f7 100644
--- a/tools/libclang/CIndex.cpp
+++ b/tools/libclang/CIndex.cpp
@@ -2901,8 +2901,17 @@ static Decl *getDeclFromExpr(Stmt *E) {
     return ME->getMemberDecl();
   if (ObjCIvarRefExpr *RE = dyn_cast<ObjCIvarRefExpr>(E))
     return RE->getDecl();
-  if (ObjCPropertyRefExpr *PRE = dyn_cast<ObjCPropertyRefExpr>(E))
-    return PRE->isExplicitProperty() ? PRE->getExplicitProperty() : 0;
+  if (ObjCPropertyRefExpr *PRE = dyn_cast<ObjCPropertyRefExpr>(E)) {
+    if (PRE->isExplicitProperty())
+      return PRE->getExplicitProperty();
+    // It could be messaging both getter and setter as in:
+    // ++myobj.myprop;
+    // in which case prefer to associate the setter since it is less obvious
+    // from inspecting the source that the setter is going to get called.
+    if (PRE->isMessagingSetter())
+      return PRE->getImplicitPropertySetter();
+    return PRE->getImplicitPropertyGetter();
+  }
   if (PseudoObjectExpr *POE = dyn_cast<PseudoObjectExpr>(E))
     return getDeclFromExpr(POE->getSyntacticForm());
   if (OpaqueValueExpr *OVE = dyn_cast<OpaqueValueExpr>(E))