Introduce "DefinedOrUnknownSVal" into the SVal class hierarchy, providing a way

to statically type various methods in SValuator/GRState as required either a
defined value or a defined-but-possibly-unknown value. This leads to various
logic cleanups in GRExprEngine, and lets the compiler enforce via type checking
our assumptions about what symbolic values are possibly undefined and what are
not.

Along the way, clean up some of the static analyzer diagnostics regarding the uses of uninitialized values.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@81579 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 6 insertions, 5 deletions

diff --git a/lib/Analysis/BugReporterVisitors.cpp b/lib/Analysis/BugReporterVisitors.cpp
index b76ffb18a6..89c9ca10ec 100644
--- a/lib/Analysis/BugReporterVisitors.cpp
+++ b/lib/Analysis/BugReporterVisitors.cpp
@@ -232,11 +232,11 @@ static void registerFindLastStore(BugReporterContext& BRC, const MemRegion *R,
 }
 
 class VISIBILITY_HIDDEN TrackConstraintBRVisitor : public BugReporterVisitor {
-  SVal Constraint;
+  DefinedSVal Constraint;
   const bool Assumption;
   bool isSatisfied;
 public:
-  TrackConstraintBRVisitor(SVal constraint, bool assumption)
+  TrackConstraintBRVisitor(DefinedSVal constraint, bool assumption)
   : Constraint(constraint), Assumption(assumption), isSatisfied(false) {}
 
   PathDiagnosticPiece* VisitNode(const ExplodedNode *N,
@@ -247,14 +247,14 @@ public:
 
     // Check if in the previous state it was feasible for this constraint
     // to *not* be true.
-    if (PrevN->getState()->assume(Constraint, !Assumption)) {
+    if (PrevN->getState()->Assume(Constraint, !Assumption)) {
 
       isSatisfied = true;
 
       // As a sanity check, make sure that the negation of the constraint
       // was infeasible in the current state.  If it is feasible, we somehow
       // missed the transition point.
-      if (N->getState()->assume(Constraint, !Assumption))
+      if (N->getState()->Assume(Constraint, !Assumption))
         return NULL;
 
       // We found the transition point for the constraint.  We now need to
@@ -295,7 +295,8 @@ public:
 };
 } // end anonymous namespace
 
-static void registerTrackConstraint(BugReporterContext& BRC, SVal Constraint,
+static void registerTrackConstraint(BugReporterContext& BRC,
+                                    DefinedSVal Constraint,
                                     bool Assumption) {
   BRC.addVisitor(new TrackConstraintBRVisitor(Constraint, Assumption));
 }