[analyzer] Don't special-case ivars backing +0 properties.

Give up this checking in order to continue tracking that these values came from
direct ivar access, which will be important in the next commit.

Part of rdar://problem/20335433

llvm-svn: 233591

1 files changed, 1 insertions, 82 deletions

diff --git a/clang/lib/StaticAnalyzer/Checkers/RetainCountChecker.cpp b/clang/lib/StaticAnalyzer/Checkers/RetainCountChecker.cpp
index 6b8596efb1b..ad4e31db943 100644
--- a/clang/lib/StaticAnalyzer/Checkers/RetainCountChecker.cpp
+++ b/clang/lib/StaticAnalyzer/Checkers/RetainCountChecker.cpp
@@ -2821,63 +2821,6 @@ static bool wasLoadedFromIvar(SymbolRef Sym) {
   return false;
 }
 
-/// Returns the property that claims this instance variable, if any.
-static const ObjCPropertyDecl *findPropForIvar(const ObjCIvarDecl *Ivar) {
-  auto IsPropertyForIvar = [Ivar](const ObjCPropertyDecl *Prop) -> bool {
-    return Prop->getPropertyIvarDecl() == Ivar;
-  };
-
-  const ObjCInterfaceDecl *Interface = Ivar->getContainingInterface();
-  auto PropIter = std::find_if(Interface->prop_begin(), Interface->prop_end(),
-                               IsPropertyForIvar);
-  if (PropIter != Interface->prop_end()) {
-    return *PropIter;
-  }
-  
-  for (auto Extension : Interface->visible_extensions()) {
-    PropIter = std::find_if(Extension->prop_begin(), Extension->prop_end(),
-                            IsPropertyForIvar);
-    if (PropIter != Extension->prop_end())
-      return *PropIter;
-  }
-
-  return nullptr;
-}
-
-namespace {
-  enum Retaining_t {
-    NonRetaining,
-    Retaining
-  };
-}
-
-static Optional<Retaining_t> getRetainSemantics(const ObjCPropertyDecl *Prop) {
-  assert(Prop->getPropertyIvarDecl() &&
-         "should only be used for properties with synthesized implementations");
-
-  if (!Prop->hasWrittenStorageAttribute()) {
-    // Don't assume anything about the retain semantics of readonly properties.
-    if (Prop->isReadOnly())
-      return None;
-
-    // Don't assume anything about readwrite properties with manually-supplied
-    // setters.
-    const ObjCMethodDecl *Setter = Prop->getSetterMethodDecl();
-    bool HasManualSetter = std::any_of(Setter->redecls_begin(),
-                                       Setter->redecls_end(),
-                                       [](const Decl *SetterRedecl) -> bool {
-      return cast<ObjCMethodDecl>(SetterRedecl)->hasBody();
-    });
-    if (HasManualSetter)
-      return None;
-
-    // If the setter /is/ synthesized, we're already relying on the retain
-    // semantics of the property. Continue as normal.
-  }
-
-  return Prop->isRetaining() ? Retaining : NonRetaining;
-}
-
 void RetainCountChecker::checkPostStmt(const ObjCIvarRefExpr *IRE,
                                        CheckerContext &C) const {
   Optional<Loc> IVarLoc = C.getSVal(IRE).getAs<Loc>();
@@ -2914,14 +2857,6 @@ void RetainCountChecker::checkPostStmt(const ObjCIvarRefExpr *IRE,
       return;
     }
 
-    // Also don't do anything if the ivar is unretained. If so, we know that
-    // there's no outstanding retain count for the value.
-    if (Kind == RetEffect::ObjC)
-      if (const ObjCPropertyDecl *Prop = findPropForIvar(IRE->getDecl()))
-        if (auto retainSemantics = getRetainSemantics(Prop))
-          if (retainSemantics.getValue() == NonRetaining)
-            return;
-
     // Note that this value has been loaded from an ivar.
     C.addTransition(setRefBinding(State, Sym, RV->withIvarAccess()));
     return;
@@ -2935,23 +2870,7 @@ void RetainCountChecker::checkPostStmt(const ObjCIvarRefExpr *IRE,
     return;
   }
 
-  bool didUpdateState = false;
-  if (Kind == RetEffect::ObjC) {
-    // Check if the ivar is known to be unretained. If so, we know that
-    // there's no outstanding retain count for the value.
-    if (const ObjCPropertyDecl *Prop = findPropForIvar(IRE->getDecl())) {
-      if (auto retainSemantics = getRetainSemantics(Prop)) {
-        if (retainSemantics.getValue() == NonRetaining) {
-          State = setRefBinding(State, Sym, PlusZero);
-          didUpdateState = true;
-        }
-      }
-    }
-  }
-
-  if (!didUpdateState)
-    State = setRefBinding(State, Sym, PlusZero.withIvarAccess());
-
+  State = setRefBinding(State, Sym, PlusZero.withIvarAccess());
   C.addTransition(State);
 }