On Tue, Aug 16, 2016 at 03:10:13PM +0200, marxin wrote:
> 2016-08-16 Martin Liska <mli...@suse.cz>
>
> * builtins.c (fold_builtin_strncmp): Rename to
> fold_builtin_strncmp_strncasecmp and support also
> strncasecmp.
> (fold_builtin_3): Handle BUILT_IN_STRNCASECMP.
> ---
> -/* Fold function call to builtin strncmp with arguments ARG1, ARG2, and LEN.
> - Return NULL_TREE if no simplification can be made. */
> +/* Fold function call to builtin strncmp (or strncasecmp) with arguments
> ARG1,
> + ARG2, and LEN. Return NULL_TREE if no simplification can be made.
> + IS_STRNCASECMP is true for strncasecmp, false otherwise. */
>
> static tree
> -fold_builtin_strncmp (location_t loc, tree arg1, tree arg2, tree len)
> +fold_builtin_strncmp_strncasecmp (location_t loc, tree arg1, tree arg2,
> + tree len, bool is_strncasecmp)
> {
> if (!validate_arg (arg1, POINTER_TYPE)
> || !validate_arg (arg2, POINTER_TYPE)
> @@ -7442,7 +7445,8 @@ fold_builtin_strncmp (location_t loc, tree arg1, tree
> arg2, tree len)
>
> /* If len parameter is one, return an expression corresponding to
> (*(const unsigned char*)arg1 - (const unsigned char*)arg2). */
> - if (tree_fits_uhwi_p (len) && tree_to_uhwi (len) == 1)
> + if (is_strncasecmp
> + && tree_fits_uhwi_p (len) && tree_to_uhwi (len) == 1)
Did you really mean to use this block for strncasecmp only (rather than for
strncmp only, i.e. !is_strncasecmp)?
Also, while you are changing this, I'd replace
tree_fits_uhwi_p (len) && tree_to_uhwi (len) == 1
with integer_onep (len).
Jakub
