mirror of
https://github.com/jart/cosmopolitan.git
synced 2025-02-01 03:53:33 +00:00
77 lines
3.2 KiB
C
77 lines
3.2 KiB
C
/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8 -*-│
|
|
│vi: set net ft=c ts=2 sts=2 sw=2 fenc=utf-8 :vi│
|
|
╞══════════════════════════════════════════════════════════════════════════════╡
|
|
│ Copyright 2021 Justine Alexandra Roberts Tunney │
|
|
│ │
|
|
│ Permission to use, copy, modify, and/or distribute this software for │
|
|
│ any purpose with or without fee is hereby granted, provided that the │
|
|
│ above copyright notice and this permission notice appear in all copies. │
|
|
│ │
|
|
│ THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL │
|
|
│ WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED │
|
|
│ WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE │
|
|
│ AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL │
|
|
│ DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR │
|
|
│ PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER │
|
|
│ TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR │
|
|
│ PERFORMANCE OF THIS SOFTWARE. │
|
|
╚─────────────────────────────────────────────────────────────────────────────*/
|
|
#include "libc/assert.h"
|
|
#include "libc/dce.h"
|
|
#include "libc/intrin/asan.internal.h"
|
|
#include "libc/nexgen32e/x86feature.h"
|
|
#include "libc/str/str.h"
|
|
|
|
typedef char xmm_t __attribute__((__vector_size__(16), __aligned__(16)));
|
|
|
|
static inline const unsigned char *rawmemchr_pure(const unsigned char *s,
|
|
unsigned char c) {
|
|
for (;; ++s) {
|
|
if (*s == c) {
|
|
return s;
|
|
}
|
|
}
|
|
}
|
|
|
|
#ifdef __x86_64__
|
|
noasan static inline const char *rawmemchr_sse(const char *s, unsigned char c) {
|
|
unsigned k;
|
|
unsigned m;
|
|
xmm_t v, *p;
|
|
xmm_t n = {c, c, c, c, c, c, c, c, c, c, c, c, c, c, c, c};
|
|
k = (uintptr_t)s & 15;
|
|
p = (const xmm_t *)((uintptr_t)s & -16);
|
|
v = *p;
|
|
m = __builtin_ia32_pmovmskb128(v == n);
|
|
m >>= k;
|
|
m <<= k;
|
|
while (!m) {
|
|
v = *++p;
|
|
m = __builtin_ia32_pmovmskb128(v == n);
|
|
}
|
|
m = __builtin_ctzll(m);
|
|
return (const char *)p + m;
|
|
}
|
|
#endif
|
|
|
|
/**
|
|
* Returns pointer to first instance of character.
|
|
*
|
|
* @param m is memory to search
|
|
* @param c is search byte which is masked with 255
|
|
* @return is pointer to first instance of c
|
|
*/
|
|
void *rawmemchr(const void *s, int c) {
|
|
#ifdef __x86_64__
|
|
const void *r;
|
|
if (X86_HAVE(SSE)) {
|
|
if (IsAsan()) __asan_verify(s, 1);
|
|
r = rawmemchr_sse(s, c);
|
|
} else {
|
|
r = rawmemchr_pure(s, c);
|
|
}
|
|
return (void *)r;
|
|
#else
|
|
return rawmemchr_pure(s, c);
|
|
#endif
|
|
}
|