Refactor logic in ExprEngine for detecting 'noreturn' methods

in NSException to a helper object in libAnalysis that can also
be used by Sema.  Not sure if the predicate name 'isImplicitNoReturn'
is the best one, but we can massage that later.

No functionality change.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@163759 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 8 insertions, 55 deletions

diff --git a/lib/StaticAnalyzer/Core/ExprEngineObjC.cpp b/lib/StaticAnalyzer/Core/ExprEngineObjC.cpp
index 4f1a76e89e..51dda19b53 100644
--- a/lib/StaticAnalyzer/Core/ExprEngineObjC.cpp
+++ b/lib/StaticAnalyzer/Core/ExprEngineObjC.cpp
@@ -132,14 +132,6 @@ void ExprEngine::VisitObjCForCollectionStmt(const ObjCForCollectionStmt *S,
   getCheckerManager().runCheckersForPostStmt(Dst, Tmp, S, *this);
 }
 
-static bool isSubclass(const ObjCInterfaceDecl *Class, IdentifierInfo *II) {
-  if (!Class)
-    return false;
-  if (Class->getIdentifier() == II)
-    return true;
-  return isSubclass(Class->getSuperClass(), II);
-}
-
 void ExprEngine::VisitObjCMessage(const ObjCMessageExpr *ME,
                                   ExplodedNode *Pred,
                                   ExplodedNodeSet &Dst) {
@@ -184,7 +176,7 @@ void ExprEngine::VisitObjCMessage(const ObjCMessageExpr *ME,
         
         // Check if the "raise" message was sent.
         assert(notNilState);
-        if (Msg->getSelector() == RaiseSel) {
+        if (ObjCNoRet.isImplicitNoReturn(ME)) {
           // If we raise an exception, for now treat it as a sink.
           // Eventually we will want to handle exceptions properly.
           Bldr.generateSink(currStmt, Pred, State);
@@ -198,52 +190,13 @@ void ExprEngine::VisitObjCMessage(const ObjCMessageExpr *ME,
         }
       }
     } else {
-      // Check for special class methods.
-      if (const ObjCInterfaceDecl *Iface = Msg->getReceiverInterface()) {
-        if (!NSExceptionII) {
-          ASTContext &Ctx = getContext();
-          NSExceptionII = &Ctx.Idents.get("NSException");
-        }
-        
-        if (isSubclass(Iface, NSExceptionII)) {
-          enum { NUM_RAISE_SELECTORS = 2 };
-          
-          // Lazily create a cache of the selectors.
-          if (!NSExceptionInstanceRaiseSelectors) {
-            ASTContext &Ctx = getContext();
-            NSExceptionInstanceRaiseSelectors =
-              new Selector[NUM_RAISE_SELECTORS];
-            SmallVector<IdentifierInfo*, NUM_RAISE_SELECTORS> II;
-            unsigned idx = 0;
-            
-            // raise:format:
-            II.push_back(&Ctx.Idents.get("raise"));
-            II.push_back(&Ctx.Idents.get("format"));
-            NSExceptionInstanceRaiseSelectors[idx++] =
-              Ctx.Selectors.getSelector(II.size(), &II[0]);
-            
-            // raise:format:arguments:
-            II.push_back(&Ctx.Idents.get("arguments"));
-            NSExceptionInstanceRaiseSelectors[idx++] =
-              Ctx.Selectors.getSelector(II.size(), &II[0]);
-          }
-          
-          Selector S = Msg->getSelector();
-          bool RaisesException = false;
-          for (unsigned i = 0; i < NUM_RAISE_SELECTORS; ++i) {
-            if (S == NSExceptionInstanceRaiseSelectors[i]) {
-              RaisesException = true;
-              break;
-            }
-          }
-          if (RaisesException) {
-            // If we raise an exception, for now treat it as a sink.
-            // Eventually we will want to handle exceptions properly.
-            Bldr.generateSink(currStmt, Pred, Pred->getState());
-            continue;
-          }
-
-        }
+      // Check for special class methods that are known to not return
+      // and that we should treat as a sink.
+      if (ObjCNoRet.isImplicitNoReturn(ME)) {
+        // If we raise an exception, for now treat it as a sink.
+        // Eventually we will want to handle exceptions properly.
+        Bldr.generateSink(currStmt, Pred, Pred->getState());
+        continue;
       }
     }