[cfe-commits] r163159 - in /cfe/trunk: lib/StaticAnalyzer/Core/SimpleSValBuilder.cpp test/Analysis/idempotent-operations.c

[Jordan Rose]

Author: jrose
Date: Tue Sep  4 14:34:58 2012
New Revision: 163159

URL: http://llvm.org/viewvc/llvm-project?rev=163159&view=rev
Log:
[analyzer] Don't use makeIntVal to create a floating-point value.

SimpleSValBuilder processes a couple trivial identities, including 'x - x'
and 'x ^ x' (both 0). However, the former could appear with arguments of
floating-point type, and we weren't checking for that. This started
triggering an assert with r163069, which checks that a constant value is
actually going to be used as an integer or pointer.

Modified:
    cfe/trunk/lib/StaticAnalyzer/Core/SimpleSValBuilder.cpp
    cfe/trunk/test/Analysis/idempotent-operations.c

Modified: cfe/trunk/lib/StaticAnalyzer/Core/SimpleSValBuilder.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/StaticAnalyzer/Core/SimpleSValBuilder.cpp?rev=163159&r1=163158&r2=163159&view=diff
==============================================================================
--- cfe/trunk/lib/StaticAnalyzer/Core/SimpleSValBuilder.cpp (original)
+++ cfe/trunk/lib/StaticAnalyzer/Core/SimpleSValBuilder.cpp Tue Sep  4 14:34:58 2012
@@ -318,7 +318,9 @@
         return makeTruthVal(false, resultTy);
       case BO_Xor:
       case BO_Sub:
-        return makeIntVal(0, resultTy);
+        if (resultTy->isIntegralOrEnumerationType())
+          return makeIntVal(0, resultTy);
+        return evalCastFromNonLoc(makeIntVal(0, /*Unsigned=*/false), resultTy);
       case BO_Or:
       case BO_And:
         return evalCastFromNonLoc(lhs, resultTy);

Modified: cfe/trunk/test/Analysis/idempotent-operations.c
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/Analysis/idempotent-operations.c?rev=163159&r1=163158&r2=163159&view=diff
==============================================================================
--- cfe/trunk/test/Analysis/idempotent-operations.c (original)
+++ cfe/trunk/test/Analysis/idempotent-operations.c Tue Sep  4 14:34:58 2012
@@ -234,3 +234,11 @@
   (void) start;
 }
 
+
+float testFloatCast(int i) {
+  float f = i;
+
+  // Don't crash when trying to create a "zero" float.
+  return f - f;
+}
+