mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-09-15 23:25:07 +00:00
18aecc2b64
This support was partially present in the existing code (look for "__tilegx__" ifdefs) but with this change you can build a working kernel using the TILE-Gx toolchain and ARCH=tilegx. Most of these files are new, generally adding a foo_64.c file where previously there was just a foo_32.c file. The ARCH=tilegx directive redirects to arch/tile, not arch/tilegx, using the existing SRCARCH mechanism in the top-level Makefile. Changes to existing files: - <asm/bitops.h> and <asm/bitops_32.h> changed to factor the include of <asm-generic/bitops/non-atomic.h> in the common header. - <asm/compat.h> and arch/tile/kernel/compat.c changed to remove the "const" markers I had put on compat_sys_execve() when trying to match some recent similar changes to the non-compat execve. It turns out the compat version wasn't "upgraded" to use const. - <asm/opcode-tile_64.h> and <asm/opcode_constants_64.h> were previously included accidentally, with the 32-bit contents. Now they have the proper 64-bit contents. Finally, I had to hack the existing hacky drivers/input/input-compat.h to add yet another "#ifdef" for INPUT_COMPAT_TEST (same as x86_64). Signed-off-by: Chris Metcalf <cmetcalf@tilera.com> Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> [drivers/input]
71 lines
2 KiB
C
71 lines
2 KiB
C
/*
|
|
* Copyright 2011 Tilera Corporation. All Rights Reserved.
|
|
*
|
|
* This program is free software; you can redistribute it and/or
|
|
* modify it under the terms of the GNU General Public License
|
|
* as published by the Free Software Foundation, version 2.
|
|
*
|
|
* This program is distributed in the hope that it will be useful, but
|
|
* WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
|
|
* NON INFRINGEMENT. See the GNU General Public License for
|
|
* more details.
|
|
*/
|
|
|
|
#include <linux/types.h>
|
|
#include <linux/string.h>
|
|
#include <linux/module.h>
|
|
|
|
void *memchr(const void *s, int c, size_t n)
|
|
{
|
|
const uint64_t *last_word_ptr;
|
|
const uint64_t *p;
|
|
const char *last_byte_ptr;
|
|
uintptr_t s_int;
|
|
uint64_t goal, before_mask, v, bits;
|
|
char *ret;
|
|
|
|
if (__builtin_expect(n == 0, 0)) {
|
|
/* Don't dereference any memory if the array is empty. */
|
|
return NULL;
|
|
}
|
|
|
|
/* Get an aligned pointer. */
|
|
s_int = (uintptr_t) s;
|
|
p = (const uint64_t *)(s_int & -8);
|
|
|
|
/* Create eight copies of the byte for which we are looking. */
|
|
goal = 0x0101010101010101ULL * (uint8_t) c;
|
|
|
|
/* Read the first word, but munge it so that bytes before the array
|
|
* will not match goal.
|
|
*
|
|
* Note that this shift count expression works because we know
|
|
* shift counts are taken mod 64.
|
|
*/
|
|
before_mask = (1ULL << (s_int << 3)) - 1;
|
|
v = (*p | before_mask) ^ (goal & before_mask);
|
|
|
|
/* Compute the address of the last byte. */
|
|
last_byte_ptr = (const char *)s + n - 1;
|
|
|
|
/* Compute the address of the word containing the last byte. */
|
|
last_word_ptr = (const uint64_t *)((uintptr_t) last_byte_ptr & -8);
|
|
|
|
while ((bits = __insn_v1cmpeq(v, goal)) == 0) {
|
|
if (__builtin_expect(p == last_word_ptr, 0)) {
|
|
/* We already read the last word in the array,
|
|
* so give up.
|
|
*/
|
|
return NULL;
|
|
}
|
|
v = *++p;
|
|
}
|
|
|
|
/* We found a match, but it might be in a byte past the end
|
|
* of the array.
|
|
*/
|
|
ret = ((char *)p) + (__insn_ctz(bits) >> 3);
|
|
return (ret <= last_byte_ptr) ? ret : NULL;
|
|
}
|
|
EXPORT_SYMBOL(memchr);
|