From 9428723d6730f4fd257e15b78d24991ae95bbd84 Mon Sep 17 00:00:00 2001
From: Jordan Rose <jordan_rose@apple.com>
Date: Thu, 6 Dec 2012 18:58:26 +0000
Subject: [PATCH] [analyzer] Remove unused fields from ExprEngine.

'currStmt', 'CleanedState', and 'EntryNode' were being set, but only ever
used locally.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@169529 91177308-0d34-0410-b5e6-96231b3b80d8
---
 .../Core/PathSensitive/ExprEngine.h           |  9 --------
 lib/StaticAnalyzer/Core/ExprEngine.cpp        | 21 +++++++------------
 lib/StaticAnalyzer/Core/ExprEngineObjC.cpp    |  6 +++---
 3 files changed, 10 insertions(+), 26 deletions(-)

diff --git a/include/clang/StaticAnalyzer/Core/PathSensitive/ExprEngine.h b/include/clang/StaticAnalyzer/Core/PathSensitive/ExprEngine.h
index 6253a70f21..f4cb9a641f 100644
--- a/include/clang/StaticAnalyzer/Core/PathSensitive/ExprEngine.h
+++ b/include/clang/StaticAnalyzer/Core/PathSensitive/ExprEngine.h
@@ -64,15 +64,6 @@ class ExprEngine : public SubEngine {
   /// svalBuilder - SValBuilder object that creates SVals from expressions.
   SValBuilder &svalBuilder;
 
-  /// EntryNode - The immediate predecessor node.
-  ExplodedNode *EntryNode;
-
-  /// CleanedState - The state for EntryNode "cleaned" of all dead
-  ///  variables and symbols (as determined by a liveness analysis).
-  ProgramStateRef CleanedState;
-
-  /// currStmt - The current block-level statement.
-  const Stmt *currStmt;
   unsigned int currStmtIdx;
   const NodeBuilderContext *currBldrCtx;
   
diff --git a/lib/StaticAnalyzer/Core/ExprEngine.cpp b/lib/StaticAnalyzer/Core/ExprEngine.cpp
index c5105412b6..2294519b7a 100644
--- a/lib/StaticAnalyzer/Core/ExprEngine.cpp
+++ b/lib/StaticAnalyzer/Core/ExprEngine.cpp
@@ -66,8 +66,7 @@ ExprEngine::ExprEngine(AnalysisManager &mgr, bool gcEnabled,
              this),
     SymMgr(StateMgr.getSymbolManager()),
     svalBuilder(StateMgr.getSValBuilder()),
-    EntryNode(NULL),
-    currStmt(NULL), currStmtIdx(0), currBldrCtx(0),
+    currStmtIdx(0), currBldrCtx(0),
     ObjCNoRet(mgr.getASTContext()),
     ObjCGCEnabled(gcEnabled), BR(mgr, *this),
     VisitedCallees(VisitedCalleesIn)
@@ -282,7 +281,7 @@ void ExprEngine::removeDead(ExplodedNode *Pred, ExplodedNodeSet &Out,
   }
 
   NumRemoveDeadBindings++;
-  CleanedState = Pred->getState();
+  ProgramStateRef CleanedState = Pred->getState();
 
   // LC is the location context being destroyed, but SymbolReaper wants a
   // location context that is still live. (If this is the top-level stack
@@ -353,18 +352,17 @@ void ExprEngine::ProcessStmt(const CFGStmt S,
   // Reclaim any unnecessary nodes in the ExplodedGraph.
   G.reclaimRecentlyAllocatedNodes();
 
-  currStmt = S.getStmt();
+  const Stmt *currStmt = S.getStmt();
   PrettyStackTraceLoc CrashInfo(getContext().getSourceManager(),
                                 currStmt->getLocStart(),
                                 "Error evaluating statement");
 
   // Remove dead bindings and symbols.
-  EntryNode = Pred;
   ExplodedNodeSet CleanedStates;
-  if (shouldRemoveDeadBindings(AMgr, S, Pred, EntryNode->getLocationContext())){
-    removeDead(EntryNode, CleanedStates, currStmt, Pred->getLocationContext());
+  if (shouldRemoveDeadBindings(AMgr, S, Pred, Pred->getLocationContext())){
+    removeDead(Pred, CleanedStates, currStmt, Pred->getLocationContext());
   } else
-    CleanedStates.Add(EntryNode);
+    CleanedStates.Add(Pred);
 
   // Visit the statement.
   ExplodedNodeSet Dst;
@@ -378,11 +376,6 @@ void ExprEngine::ProcessStmt(const CFGStmt S,
 
   // Enqueue the new nodes onto the work list.
   Engine.enqueue(Dst, currBldrCtx->getBlock(), currStmtIdx);
-
-  // NULL out these variables to cleanup.
-  CleanedState = NULL;
-  EntryNode = NULL;
-  currStmt = 0;
 }
 
 void ExprEngine::ProcessInitializer(const CFGInitializer Init,
@@ -393,7 +386,7 @@ void ExprEngine::ProcessInitializer(const CFGInitializer Init,
                                 BMI->getSourceLocation(),
                                 "Error evaluating initializer");
 
-  // We don't set EntryNode and currStmt. And we don't clean up state.
+  // We don't clean up dead bindings here.
   const StackFrameContext *stackFrame =
                            cast<StackFrameContext>(Pred->getLocationContext());
   const CXXConstructorDecl *decl =
diff --git a/lib/StaticAnalyzer/Core/ExprEngineObjC.cpp b/lib/StaticAnalyzer/Core/ExprEngineObjC.cpp
index 51dda19b53..de73dd7c3e 100644
--- a/lib/StaticAnalyzer/Core/ExprEngineObjC.cpp
+++ b/lib/StaticAnalyzer/Core/ExprEngineObjC.cpp
@@ -179,13 +179,13 @@ void ExprEngine::VisitObjCMessage(const ObjCMessageExpr *ME,
         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);
+          Bldr.generateSink(ME, Pred, State);
           continue;
         }
         
         // Generate a transition to non-Nil state.
         if (notNilState != State) {
-          Pred = Bldr.generateNode(currStmt, Pred, notNilState);
+          Pred = Bldr.generateNode(ME, Pred, notNilState);
           assert(Pred && "Should have cached out already!");
         }
       }
@@ -195,7 +195,7 @@ void ExprEngine::VisitObjCMessage(const ObjCMessageExpr *ME,
       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());
+        Bldr.generateSink(ME, Pred, Pred->getState());
         continue;
       }
     }
-- 
2.40.0