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, 4 insertions, 7 deletions

diff --git a/lib/Analysis/SimpleConstraintManager.cpp b/lib/Analysis/SimpleConstraintManager.cpp
index db3d68a2c7..e4ad85aa83 100644
--- a/lib/Analysis/SimpleConstraintManager.cpp
+++ b/lib/Analysis/SimpleConstraintManager.cpp
@@ -56,11 +56,8 @@ bool SimpleConstraintManager::canReasonAbout(SVal X) const {
 }
 
 const GRState *SimpleConstraintManager::Assume(const GRState *state,
-                                               SVal Cond, bool Assumption) {
-  if (Cond.isUnknown()) {
-    return state;
-  }
-
+                                               DefinedSVal Cond,
+                                               bool Assumption) {
   if (isa<NonLoc>(Cond))
     return Assume(state, cast<NonLoc>(Cond), Assumption);
   else
@@ -226,8 +223,8 @@ const GRState *SimpleConstraintManager::AssumeSymInt(const GRState *state,
 }
 
 const GRState *SimpleConstraintManager::AssumeInBound(const GRState *state,
-                                                      SVal Idx,
-                                                      SVal UpperBound,
+                                                      DefinedSVal Idx,
+                                                      DefinedSVal UpperBound,
                                                       bool Assumption) {
 
   // Only support ConcreteInt for now.