(fold, case EQ_EXPR): Remove code that converts mod to unsigned mod;

it isn't correct for negative operands.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@4995 138bc75d-0d04-0410-961f-82ee72b054a4

diff --git a/gcc/fold-const.c b/gcc/fold-const.c
index 5b9d851..5f23e98 100644 (file)
--- a/gcc/fold-const.c
+++ b/gcc/fold-const.c
@@ -4203,6 +4203,10 @@ fold (expr)
                           arg1));
        }
 
+      /* It would be nice to do this since it generates better code.
+        Unfortunately, it doesn't produce the correct result if the
+        first operand is negative.  */
+#if 0
       /* If this is an NE or EQ comparison of zero against the result of a
         signed MOD operation, make the MOD operation unsigned since it
         is simpler and equivalent.  */
@@ -4221,6 +4225,7 @@ fold (expr)
 
          return build (code, type, newmod, convert (newtype, arg1));
        }
+#endif
 
       /* If this is an NE comparison of zero with an AND of one, remove the
         comparison since the AND will give the correct value.  */