[analyzer] Make the entries in 'Environment' context-sensitive by making entries map from

(Stmt*,LocationContext*) pairs to SVals instead of Stmt* to SVals.

This is needed to support basic IPA via inlining.  Without this, we cannot tell
if a Stmt* binding is part of the current analysis scope (StackFrameContext) or
part of a parent context.

This change introduces an uglification of the use of getSVal(), and thus takes
two steps forward and one step back.  There are also potential performance implications
of enlarging the Environment.  Both can be addressed going forward by refactoring the
APIs and optimizing the internal representation of Environment.  This patch
mainly introduces the functionality upon when we want to build upon (and clean up).

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@147688 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 24 insertions, 17 deletions

diff --git a/lib/StaticAnalyzer/Checkers/RetainCountChecker.cpp b/lib/StaticAnalyzer/Checkers/RetainCountChecker.cpp
index 24df0083f5..8ba1edbb41 100644
--- a/lib/StaticAnalyzer/Checkers/RetainCountChecker.cpp
+++ b/lib/StaticAnalyzer/Checkers/RetainCountChecker.cpp
@@ -1312,7 +1312,7 @@ RetainSummaryManager::getInstanceMethodSummary(const ObjCMessage &msg,
   SVal receiverV;
 
   if (Receiver) {
-    receiverV = state->getSValAsScalarOrLoc(Receiver);
+    receiverV = state->getSValAsScalarOrLoc(Receiver, LC);
 
     // FIXME: Eventually replace the use of state->get<RefBindings> with
     // a generic API for reasoning about the Objective-C types of symbolic
@@ -1841,6 +1841,7 @@ PathDiagnosticPiece *CFRefReportVisitor::VisitNode(const ExplodedNode *N,
   // Check if the type state has changed.
   const ProgramState *PrevSt = PrevN->getState();
   const ProgramState *CurrSt = N->getState();
+  const LocationContext *LCtx = N->getLocationContext();
 
   const RefVal* CurrT = CurrSt->get<RefBindings>(Sym);
   if (!CurrT) return NULL;
@@ -1860,7 +1861,7 @@ PathDiagnosticPiece *CFRefReportVisitor::VisitNode(const ExplodedNode *N,
 
     if (const CallExpr *CE = dyn_cast<CallExpr>(S)) {
       // Get the name of the callee (if it is available).
-      SVal X = CurrSt->getSValAsScalarOrLoc(CE->getCallee());
+      SVal X = CurrSt->getSValAsScalarOrLoc(CE->getCallee(), LCtx);
       if (const FunctionDecl *FD = X.getAsFunctionDecl())
         os << "Call to function '" << *FD << '\'';
       else
@@ -1920,7 +1921,7 @@ PathDiagnosticPiece *CFRefReportVisitor::VisitNode(const ExplodedNode *N,
 
         // Retrieve the value of the argument.  Is it the symbol
         // we are interested in?
-        if (CurrSt->getSValAsScalarOrLoc(*AI).getAsLocSymbol() != Sym)
+        if (CurrSt->getSValAsScalarOrLoc(*AI, LCtx).getAsLocSymbol() != Sym)
           continue;
 
         // We have an argument.  Get the effect!
@@ -1929,7 +1930,8 @@ PathDiagnosticPiece *CFRefReportVisitor::VisitNode(const ExplodedNode *N,
     }
     else if (const ObjCMessageExpr *ME = dyn_cast<ObjCMessageExpr>(S)) {
       if (const Expr *receiver = ME->getInstanceReceiver())
-        if (CurrSt->getSValAsScalarOrLoc(receiver).getAsLocSymbol() == Sym) {
+        if (CurrSt->getSValAsScalarOrLoc(receiver, LCtx)
+              .getAsLocSymbol() == Sym) {
           // The symbol we are tracking is the receiver.
           AEffects.push_back(Summ->getReceiverEffect());
         }
@@ -1957,7 +1959,8 @@ PathDiagnosticPiece *CFRefReportVisitor::VisitNode(const ExplodedNode *N,
     if (contains(AEffects, MakeCollectable)) {
       // Get the name of the function.
       const Stmt *S = cast<StmtPoint>(N->getLocation()).getStmt();
-      SVal X = CurrSt->getSValAsScalarOrLoc(cast<CallExpr>(S)->getCallee());
+      SVal X =
+        CurrSt->getSValAsScalarOrLoc(cast<CallExpr>(S)->getCallee(), LCtx);
       const FunctionDecl *FD = X.getAsFunctionDecl();
 
       if (GCEnabled) {
@@ -2069,7 +2072,7 @@ PathDiagnosticPiece *CFRefReportVisitor::VisitNode(const ExplodedNode *N,
   for (Stmt::const_child_iterator I = S->child_begin(), E = S->child_end();
        I!=E; ++I)
     if (const Expr *Exp = dyn_cast_or_null<Expr>(*I))
-      if (CurrSt->getSValAsScalarOrLoc(Exp).getAsLocSymbol() == Sym) {
+      if (CurrSt->getSValAsScalarOrLoc(Exp, LCtx).getAsLocSymbol() == Sym) {
         P->addRange(Exp->getSourceRange());
         break;
       }
@@ -2505,7 +2508,8 @@ void RetainCountChecker::checkPostStmt(const BlockExpr *BE,
 
   const ProgramState *state = C.getState();
   const BlockDataRegion *R =
-    cast<BlockDataRegion>(state->getSVal(BE).getAsRegion());
+    cast<BlockDataRegion>(state->getSVal(BE,
+                                         C.getLocationContext()).getAsRegion());
 
   BlockDataRegion::referenced_vars_iterator I = R->referenced_vars_begin(),
                                             E = R->referenced_vars_end();
@@ -2555,7 +2559,7 @@ void RetainCountChecker::checkPostStmt(const CastExpr *CE,
   }
   
   const ProgramState *state = C.getState();
-  SymbolRef Sym = state->getSVal(CE).getAsLocSymbol();
+  SymbolRef Sym = state->getSVal(CE, C.getLocationContext()).getAsLocSymbol();
   if (!Sym)
     return;
   const RefVal* T = state->get<RefBindings>(Sym);
@@ -2579,7 +2583,7 @@ void RetainCountChecker::checkPostStmt(const CallExpr *CE,
   // Get the callee.
   const ProgramState *state = C.getState();
   const Expr *Callee = CE->getCallee();
-  SVal L = state->getSVal(Callee);
+  SVal L = state->getSVal(Callee, C.getLocationContext());
 
   RetainSummaryManager &Summaries = getSummaryManager(C);
   const RetainSummary *Summ = 0;
@@ -2599,7 +2603,7 @@ void RetainCountChecker::checkPostStmt(const CallExpr *CE,
   if (!Summ)
     Summ = Summaries.getDefaultSummary();
 
-  checkSummary(*Summ, CallOrObjCMessage(CE, state), C);
+  checkSummary(*Summ, CallOrObjCMessage(CE, state, C.getLocationContext()), C);
 }
 
 void RetainCountChecker::checkPostStmt(const CXXConstructExpr *CE,
@@ -2616,7 +2620,7 @@ void RetainCountChecker::checkPostStmt(const CXXConstructExpr *CE,
     return;
 
   const ProgramState *state = C.getState();
-  checkSummary(*Summ, CallOrObjCMessage(CE, state), C);
+  checkSummary(*Summ, CallOrObjCMessage(CE, state, C.getLocationContext()), C);
 }
 
 void RetainCountChecker::checkPostObjCMessage(const ObjCMessage &Msg, 
@@ -2637,7 +2641,7 @@ void RetainCountChecker::checkPostObjCMessage(const ObjCMessage &Msg,
   if (!Summ)
     return;
 
-  checkSummary(*Summ, CallOrObjCMessage(Msg, state), C);
+  checkSummary(*Summ, CallOrObjCMessage(Msg, state, C.getLocationContext()), C);
 }
 
 /// GetReturnType - Used to get the return type of a message expression or
@@ -2737,7 +2741,8 @@ void RetainCountChecker::checkSummary(const RetainSummary &Summ,
 
     case RetEffect::OwnedAllocatedSymbol:
     case RetEffect::OwnedSymbol: {
-      SymbolRef Sym = state->getSVal(CallOrMsg.getOriginExpr()).getAsSymbol();
+      SymbolRef Sym = state->getSVal(CallOrMsg.getOriginExpr(),
+                                     C.getLocationContext()).getAsSymbol();
       if (!Sym)
         break;
 
@@ -2764,7 +2769,7 @@ void RetainCountChecker::checkSummary(const RetainSummary &Summ,
     case RetEffect::ARCNotOwnedSymbol:
     case RetEffect::NotOwnedSymbol: {
       const Expr *Ex = CallOrMsg.getOriginExpr();
-      SymbolRef Sym = state->getSVal(Ex).getAsSymbol();
+      SymbolRef Sym = state->getSVal(Ex, C.getLocationContext()).getAsSymbol();
       if (!Sym)
         break;
 
@@ -3030,14 +3035,15 @@ bool RetainCountChecker::evalCall(const CallExpr *CE, CheckerContext &C) const {
     return false;
 
   // Bind the return value.
-  SVal RetVal = state->getSVal(CE->getArg(0));
+  const LocationContext *LCtx = C.getLocationContext();
+  SVal RetVal = state->getSVal(CE->getArg(0), LCtx);
   if (RetVal.isUnknown()) {
     // If the receiver is unknown, conjure a return value.
     SValBuilder &SVB = C.getSValBuilder();
     unsigned Count = C.getCurrentBlockCount();
     SVal RetVal = SVB.getConjuredSymbolVal(0, CE, ResultTy, Count);
   }
-  state = state->BindExpr(CE, RetVal, false);
+  state = state->BindExpr(CE, LCtx, RetVal, false);
 
   // FIXME: This should not be necessary, but otherwise the argument seems to be
   // considered alive during the next statement.
@@ -3072,7 +3078,8 @@ void RetainCountChecker::checkPreStmt(const ReturnStmt *S,
     return;
 
   const ProgramState *state = C.getState();
-  SymbolRef Sym = state->getSValAsScalarOrLoc(RetE).getAsLocSymbol();
+  SymbolRef Sym =
+    state->getSValAsScalarOrLoc(RetE, C.getLocationContext()).getAsLocSymbol();
   if (!Sym)
     return;