[PATCH] Fix fold-const typo

[Jakub Jelinek]

On Wed, May 15, 2002 at 09:15:27AM +0200, Eric Botcazou wrote:
>  * fold-const.c (fold) [LT_EXPR]: Move the transformation of a
>  comparison against the highest or lowest integer value before
>  the 'X >= CST to X > (CST - 1)' and 'X < CST to X <= (CST - 1)'
>  transformation and that of an unsigned comparison against 0
>  right after.

While at it, I think there is a typo in the code you're moving.
For signed comparisons, instead of testing whether the constant
is minimum signed value (like {CHAR,SHORT,INT,LONG}_MIN) it tests
whether the constant is (say for 32-bit HOST_WIDE_INT and
16-bit comparison 0xffffffff00008000).
E.g. it can be seen say on
short i;
int foo (void)
{
  if (i > -32768)
    return 1;
  return 2;
}
(the code won't be faster in this case, but in more complicated tests it
could).
Bootstrapped on i386-redhat-linux on top of Eric's patch, no regressions.
Ok to commit?

2002-05-15  Jakub Jelinek  <jakub@redhat.com>

	* fold-const.c (fold): Fix a typo.

--- gcc/fold-const.c.jj	Wed May 15 14:02:54 2002
+++ gcc/fold-const.c	Wed May 15 14:06:09 2002
@@ -6530,7 +6530,7 @@ fold (expr)
 
 	    else if (TREE_INT_CST_HIGH (arg1) == -1
 		     && (TREE_INT_CST_LOW (arg1)
-			 == ((unsigned HOST_WIDE_INT) 1 << (width - 1)))
+			 == ((unsigned HOST_WIDE_INT) -1 << (width - 1)))
 		     && ! TREE_UNSIGNED (TREE_TYPE (arg1)))
 	      switch (TREE_CODE (t))
 		{


	Jakub