This is the mail archive of the
gcc-patches@gcc.gnu.org
mailing list for the GCC project.
Re: [PATCH 1/3] Fold BUILT_IN_STRNCASECMP
On 08/17/2016 09:10 AM, Jakub Jelinek wrote:
> Did you really mean to use this block for strncasecmp only (rather than for
> strncmp only, i.e. !is_strncasecmp)?
Sure, that was a typo. Unfortunately I had a test case with strings that was
eaten by fold_const_call. I enhanced test coverage for that.
>
> Also, while you are changing this, I'd replace
> tree_fits_uhwi_p (len) && tree_to_uhwi (len) == 1
> with integer_onep (len).
Fixed in v2.
Martin
>
> Jakub
>From f1c30311d2f9274bd213fa703ad51da8151a1b1b Mon Sep 17 00:00:00 2001
From: marxin <mliska@suse.cz>
Date: Tue, 16 Aug 2016 15:10:13 +0200
Subject: [PATCH 1/3] Fold BUILT_IN_STRNCASECMP
gcc/ChangeLog:
2016-08-16 Martin Liska <mliska@suse.cz>
* builtins.c (fold_builtin_strncmp): Rename to
fold_builtin_strncmp_strncasecmp and support also
strncasecmp.
(fold_builtin_3): Handle BUILT_IN_STRNCASECMP.
---
gcc/builtins.c | 18 ++++++++++++------
1 file changed, 12 insertions(+), 6 deletions(-)
diff --git a/gcc/builtins.c b/gcc/builtins.c
index 03a0dc8..3926049 100644
--- a/gcc/builtins.c
+++ b/gcc/builtins.c
@@ -150,7 +150,8 @@ static tree fold_builtin_strchr (location_t, tree, tree, tree);
static tree fold_builtin_memchr (location_t, tree, tree, tree, tree);
static tree fold_builtin_memcmp (location_t, tree, tree, tree);
static tree fold_builtin_strcmp (location_t, tree, tree);
-static tree fold_builtin_strncmp (location_t, tree, tree, tree);
+static tree fold_builtin_strncmp_strncasecmp (location_t, tree, tree, tree,
+ bool);
static tree fold_builtin_isascii (location_t, tree);
static tree fold_builtin_toascii (location_t, tree);
static tree fold_builtin_isdigit (location_t, tree);
@@ -7383,11 +7384,13 @@ fold_builtin_strcmp (location_t loc, tree arg1, tree arg2)
return NULL_TREE;
}
-/* 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 +7445,7 @@ 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 && integer_onep (len))
{
tree cst_uchar_node = build_type_variant (unsigned_char_type_node, 1, 0);
tree cst_uchar_ptr_node
@@ -8483,7 +8486,10 @@ fold_builtin_3 (location_t loc, tree fndecl,
break;
case BUILT_IN_STRNCMP:
- return fold_builtin_strncmp (loc, arg0, arg1, arg2);
+ return fold_builtin_strncmp_strncasecmp (loc, arg0, arg1, arg2, false);
+
+ case BUILT_IN_STRNCASECMP:
+ return fold_builtin_strncmp_strncasecmp (loc, arg0, arg1, arg2, true);
case BUILT_IN_MEMCHR:
return fold_builtin_memchr (loc, arg0, arg1, arg2, type);
--
2.9.2