From: Ted Kremenek <kremenek@apple.com>
Date: Tue, 6 Oct 2009 03:44:49 +0000 (+0000)
Subject: Fix crash introduced by r83358 where a symbol could be eagerly
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=b1d042212fbb3f6a08864b703b7bdf0dca58fd9c;p=clang

Fix crash introduced by r83358 where a symbol could be eagerly
evaluated to an APSInt with a different bitwidth than the other
operand in a binary expression.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@83368 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/Analysis/SimpleSValuator.cpp b/lib/Analysis/SimpleSValuator.cpp
index 2869fabea3..636ce15c33 100644
--- a/lib/Analysis/SimpleSValuator.cpp
+++ b/lib/Analysis/SimpleSValuator.cpp
@@ -349,8 +349,13 @@ SVal SimpleSValuator::EvalBinOpNN(const GRState *state,
       // Does the symbol simplify to a constant?
       if (Sym->getType(ValMgr.getContext())->isIntegerType())
         if (const llvm::APSInt *Constant = state->getSymVal(Sym)) {
-          lhs = nonloc::ConcreteInt(*Constant);
-          continue;
+          // What should we convert it to?
+          if (nonloc::ConcreteInt *rhs_I = dyn_cast<nonloc::ConcreteInt>(&rhs)){
+            BasicValueFactory &BVF = ValMgr.getBasicValueFactory();
+            lhs = nonloc::ConcreteInt(BVF.Convert(rhs_I->getValue(),
+                                                  *Constant));
+            continue;
+          }
         }
       
       if (isa<nonloc::ConcreteInt>(rhs)) {
diff --git a/test/Analysis/misc-ps.m b/test/Analysis/misc-ps.m
index 565dc61f3b..10e5823c20 100644
--- a/test/Analysis/misc-ps.m
+++ b/test/Analysis/misc-ps.m
@@ -681,3 +681,14 @@ void *rdar7152418_bar();
   return 1;
 }
 
+// Test constant-folding of symbolic values, automatically handling type
+// conversions of the symbol as necessary.  Previously this would crash
+// once we started eagerly evaluating symbols whose values were constrained
+// to a single value.
+void test_constant_symbol(signed char x) {
+  while (1) {
+    if (x == ((signed char) 0)) {}
+  }
+}
+
+