Make more functions friendly to Address Sanitizer

This commit is contained in:
Justine Tunney 2021-02-02 03:45:31 -08:00
parent 3ab76b2312
commit cbfd4ccd1e
70 changed files with 1267 additions and 291 deletions

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@ -1,7 +1,7 @@
/*-*- 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 2020 Justine Alexandra Roberts Tunney
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
@ -18,12 +18,14 @@
*/
#include "libc/str/str.h"
void *tinymemccpy(void *dst, const void *src, int termchar, size_t limit) {
size_t i;
unsigned char *d;
const unsigned char *s;
for (termchar &= 0xff, d = dst, s = src, i = 0; i < limit; ++i) {
if ((d[i] = s[i]) == termchar) return d + i + 1;
}
return NULL;
/**
* Returns pointer to first instance of character, the BSD way.
*
* @param s is a NUL-terminated string
* @param is masked with 255 as byte to search for
* @return is pointer to first instance of c or NULL if not found,
* noting that c being NUL will return a pointer to terminator
*/
char *index(const char *s, int c) {
return strchr(s, c);
}

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@ -18,8 +18,14 @@
*/
#include "libc/str/str.h"
static noasan uint64_t UncheckedAlignedRead64(unsigned char *p) {
return (uint64_t)p[7] << 070 | (uint64_t)p[6] << 060 | (uint64_t)p[5] << 050 |
(uint64_t)p[4] << 040 | (uint64_t)p[3] << 030 | (uint64_t)p[2] << 020 |
(uint64_t)p[1] << 010 | (uint64_t)p[0] << 000;
}
/**
* Copies at most 𝑛 bytes from 𝑠 to 𝑑 until 𝑐 is encountered.
* Copies at most N bytes from SRC to DST until 𝑐 is encountered.
*
* This is little-known C Standard Library approach, dating back to the
* Fourth Edition of System Five, for copying a C strings to fixed-width
@ -39,17 +45,46 @@
* char cstrbuf[16];
* snprintf(cstrbuf, sizeof(cstrbuf), "%s", CSTR);
*
* @return 𝑑 + idx(𝑐) + 1, or NULL if 𝑐 𝑠
* @note 𝑑 and 𝑠 can't overlap
* @param c is search character and is masked with 255
* @return DST + idx(c) + 1, or NULL if 𝑐 𝑠
* @note DST and SRC can't overlap
* @asyncsignalsafe
*/
void *memccpy(void *d, const void *s, int c, size_t n) {
const char *p, *pe;
p = s;
if ((pe = memchr(p, c, n))) {
return mempcpy(d, s, pe - p + 1);
} else {
memcpy(d, s, n);
return NULL;
void *memccpy(void *dst, const void *src, int c, size_t n) {
size_t i;
uint64_t v, w;
unsigned char *d;
unsigned char *pd;
const unsigned char *s;
i = 0;
d = dst;
s = src;
c &= 255;
v = 0x0101010101010101 * c;
for (; (uintptr_t)(s + i) & 7; ++i) {
if (i == n) return NULL;
if ((d[i] = s[i]) == c) return d + i + 1;
}
for (; i + 8 <= n; i += 8) {
w = UncheckedAlignedRead64(s + i);
if (~(w ^ v) & ((w ^ v) - 0x0101010101010101) & 0x8080808080808080) {
break;
} else {
pd = d + i;
pd[0] = (w >> 000) & 255;
pd[1] = (w >> 010) & 255;
pd[2] = (w >> 020) & 255;
pd[3] = (w >> 030) & 255;
pd[4] = (w >> 040) & 255;
pd[5] = (w >> 050) & 255;
pd[6] = (w >> 060) & 255;
pd[7] = (w >> 070) & 255;
}
}
for (; i < n; ++i) {
if ((d[i] = s[i]) == c) {
return d + i + 1;
}
}
return NULL;
}

47
libc/str/memchr.c Normal file
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@ -0,0 +1,47 @@
/*-*- 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/str/str.h"
/**
* Returns pointer to first instance of character.
*
* @param m is memory to search
* @param c is search byte which is masked with 255
* @param n is byte length of p
* @return is pointer to first instance of c or NULL if not found
* @asyncsignalsafe
*/
void *memchr(const void *m, int c, size_t n) {
uint64_t v, w;
const unsigned char *p, *pe;
c &= 255;
v = 0x0101010101010101 * c;
for (p = (const unsigned char *)m, pe = p + n; p + 8 <= pe; p += 8) {
w = (uint64_t)p[7] << 070 | (uint64_t)p[6] << 060 | (uint64_t)p[5] << 050 |
(uint64_t)p[4] << 040 | (uint64_t)p[3] << 030 | (uint64_t)p[2] << 020 |
(uint64_t)p[1] << 010 | (uint64_t)p[0] << 000;
if ((w = ~(w ^ v) & ((w ^ v) - 0x0101010101010101) & 0x8080808080808080)) {
return p + ((unsigned)__builtin_ctzll(w) >> 3);
}
}
for (; p < pe; ++p) {
if (*p == c) return p;
}
return NULL;
}

160
libc/str/memmove-pure.c Normal file
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@ -0,0 +1,160 @@
/*-*- 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/str/str.h"
typedef long long xmm_t __attribute__((__vector_size__(16), __aligned__(1)));
/**
* Copies memory.
*
* DST and SRC may overlap.
*
* @param dst is destination
* @param src is memory to copy
* @param n is number of bytes to copy
* @return dst
* @asyncsignalsafe
*/
void *memmove$pure(void *dst, const void *src, size_t n) {
size_t i;
xmm_t v, w;
char *d, *r;
const char *s;
uint64_t a, b;
d = dst;
s = src;
switch (n) {
case 9 ... 15:
__builtin_memcpy(&a, s, 8);
__builtin_memcpy(&b, s + n - 8, 8);
__builtin_memcpy(d, &a, 8);
__builtin_memcpy(d + n - 8, &b, 8);
return d;
case 5 ... 7:
__builtin_memcpy(&a, s, 4);
__builtin_memcpy(&b, s + n - 4, 4);
__builtin_memcpy(d, &a, 4);
__builtin_memcpy(d + n - 4, &b, 4);
return d;
case 17 ... 32:
__builtin_memcpy(&v, s, 16);
__builtin_memcpy(&w, s + n - 16, 16);
__builtin_memcpy(d, &v, 16);
__builtin_memcpy(d + n - 16, &w, 16);
return d;
case 16:
__builtin_memcpy(&v, s, 16);
__builtin_memcpy(d, &v, 16);
return d;
case 0:
return d;
case 1:
*d = *s;
return d;
case 8:
__builtin_memcpy(&a, s, 8);
__builtin_memcpy(d, &a, 8);
return d;
case 4:
__builtin_memcpy(&a, s, 4);
__builtin_memcpy(d, &a, 4);
return d;
case 2:
__builtin_memcpy(&a, s, 2);
__builtin_memcpy(d, &a, 2);
return d;
case 3:
__builtin_memcpy(&a, s, 2);
__builtin_memcpy(&b, s + 1, 2);
__builtin_memcpy(d, &a, 2);
__builtin_memcpy(d + 1, &b, 2);
return d;
default:
r = d;
if (d > s) {
do {
n -= 32;
__builtin_memcpy(&v, s + n, 16);
__builtin_memcpy(&w, s + n + 16, 16);
__builtin_memcpy(d + n, &v, 16);
__builtin_memcpy(d + n + 16, &w, 16);
} while (n >= 32);
} else {
i = 0;
do {
__builtin_memcpy(&v, s + i, 16);
__builtin_memcpy(&w, s + i + 16, 16);
__builtin_memcpy(d + i, &v, 16);
__builtin_memcpy(d + i + 16, &w, 16);
} while ((i += 32) + 32 <= n);
d += i;
s += i;
n -= i;
}
switch (n) {
case 0:
return r;
case 17 ... 31:
__builtin_memcpy(&v, s, 16);
__builtin_memcpy(&w, s + n - 16, 16);
__builtin_memcpy(d, &v, 16);
__builtin_memcpy(d + n - 16, &w, 16);
return r;
case 9 ... 15:
__builtin_memcpy(&a, s, 8);
__builtin_memcpy(&b, s + n - 8, 8);
__builtin_memcpy(d, &a, 8);
__builtin_memcpy(d + n - 8, &b, 8);
return r;
case 5 ... 7:
__builtin_memcpy(&a, s, 4);
__builtin_memcpy(&b, s + n - 4, 4);
__builtin_memcpy(d, &a, 4);
__builtin_memcpy(d + n - 4, &b, 4);
return r;
case 16:
__builtin_memcpy(&v, s, 16);
__builtin_memcpy(d, &v, 16);
return r;
case 8:
__builtin_memcpy(&a, s, 8);
__builtin_memcpy(d, &a, 8);
return r;
case 4:
__builtin_memcpy(&a, s, 4);
__builtin_memcpy(d, &a, 4);
return r;
case 1:
*d = *s;
return r;
case 2:
__builtin_memcpy(&a, s, 2);
__builtin_memcpy(d, &a, 2);
return r;
case 3:
__builtin_memcpy(&a, s, 2);
__builtin_memcpy(&b, s + 1, 2);
__builtin_memcpy(d, &a, 2);
__builtin_memcpy(d + 1, &b, 2);
return r;
default:
unreachable;
}
}
}

100
libc/str/memset-pure.c Normal file
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@ -0,0 +1,100 @@
/*-*- 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/str/str.h"
/**
* Sets memory.
*
* @param p is memory address
* @param c is masked with 255 and used as repeated byte
* @param n is byte length
* @return p
* @asyncsignalsafe
*/
void *memset$pure(void *p, int c, size_t n) {
char *b;
uint64_t x;
b = p;
x = 0x0101010101010101 * (c & 0xff);
switch (n) {
case 0:
return p;
case 1:
__builtin_memcpy(b, &x, 1);
return p;
case 2:
__builtin_memcpy(b, &x, 2);
return p;
case 3:
__builtin_memcpy(b, &x, 2);
__builtin_memcpy(b + 1, &x, 2);
return p;
case 4:
__builtin_memcpy(b, &x, 4);
return p;
case 5 ... 7:
__builtin_memcpy(b, &x, 4);
__builtin_memcpy(b + n - 4, &x, 4);
return p;
case 8:
__builtin_memcpy(b, &x, 8);
return p;
case 9 ... 16:
__builtin_memcpy(b, &x, 8);
__builtin_memcpy(b + n - 8, &x, 8);
return p;
default:
do {
n -= 16;
__builtin_memcpy(b + n, &x, 8);
asm volatile("" ::: "memory");
__builtin_memcpy(b + n + 8, &x, 8);
} while (n >= 16);
switch (n) {
case 0:
return p;
case 1:
__builtin_memcpy(b, &x, 1);
return p;
case 2:
__builtin_memcpy(b, &x, 2);
return p;
case 3:
__builtin_memcpy(b, &x, 2);
__builtin_memcpy(b + 1, &x, 2);
return p;
case 4:
__builtin_memcpy(b, &x, 4);
return p;
case 5 ... 7:
__builtin_memcpy(b, &x, 4);
__builtin_memcpy(b + n - 4, &x, 4);
return p;
case 8:
__builtin_memcpy(b, &x, 8);
return p;
case 9 ... 15:
__builtin_memcpy(b, &x, 8);
__builtin_memcpy(b + n - 8, &x, 8);
return p;
default:
unreachable;
}
}
}

53
libc/str/rawmemchr.c Normal file
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@ -0,0 +1,53 @@
/*-*- 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/str/str.h"
static noasan uint64_t UncheckedAlignedRead64(unsigned char *p) {
return (uint64_t)p[7] << 070 | (uint64_t)p[6] << 060 | (uint64_t)p[5] << 050 |
(uint64_t)p[4] << 040 | (uint64_t)p[3] << 030 | (uint64_t)p[2] << 020 |
(uint64_t)p[1] << 010 | (uint64_t)p[0] << 000;
}
/**
* 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 *m, int c) {
uint64_t v, w;
const unsigned char *s;
s = m;
c &= 255;
v = 0x0101010101010101 * c;
for (; (uintptr_t)s & 7; ++s) {
if (*s == c) return s;
}
for (;; s += 8) {
w = UncheckedAlignedRead64(s);
if ((w = ~(w ^ v) & ((w ^ v) - 0x0101010101010101) & 0x8080808080808080)) {
s += (unsigned)__builtin_ctzll(w) >> 3;
break;
}
}
assert(*s == c);
return s;
}

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@ -90,7 +90,6 @@ void *memeqmask(void *, const void *, const void *, size_t) memcpyesque;
size_t strlen(const char *) strlenesque;
size_t strnlen(const char *, size_t) strlenesque;
size_t strnlen_s(const char *, size_t);
size_t strlen$pure(const char *) strlenesque;
char *strchr(const char *, int) strlenesque;
char *index(const char *, int) strlenesque;
void *memchr(const void *, int, size_t) strlenesque;
@ -246,8 +245,8 @@ char *strsignal(int) returnsnonnull libcesque;
cosmopolitan § strings » optimizations
*/
#define __memcpy_isgoodsize(SIZE) \
(__builtin_constant_p(SIZE) && ((SIZE) <= __BIGGEST_ALIGNMENT__ * 2 && \
#define __memcpy_isgoodsize(SIZE) \
(__builtin_constant_p(SIZE) && ((SIZE) <= __BIGGEST_ALIGNMENT__ && \
__builtin_popcountl((unsigned)(SIZE)) == 1))
#define __memset_isgoodsize(SIZE) \
@ -361,15 +360,44 @@ char *strsignal(int) returnsnonnull libcesque;
})
#endif /* hosted/sse2/unbloat */
#ifdef __FSANITIZE_ADDRESS__
/*───────────────────────────────────────────────────────────────────────────│─╗
cosmopolitan § strings » address sanitizer
*/
void *memset$pure(void *, int, size_t) memcpyesque;
void *memmove$pure(void *, const void *, size_t) memcpyesque;
size_t strlen$pure(const char *) strlenesque;
size_t strcspn$pure(const char *, const char *) strlenesque;
#if defined(__FSANITIZE_ADDRESS__)
#define strcspn(STR, REJECT) strcspn$pure(STR, REJECT)
#ifdef strlen
#undef strlen
#endif
#define strlen(s) strlen$pure(s)
#define strlen(STR) \
(__builtin_constant_p(STR) ? __builtin_strlen(STR) : strlen$pure(STR))
#undef memset
#define memset(DST, CHAR, SIZE) \
(__memcpy_isgoodsize(SIZE) ? __builtin_memset(DST, CHAR, SIZE) \
: memset$pure(DST, CHAR, SIZE))
#undef memmove
#define memmove(DST, SRC, SIZE) \
(__memcpy_isgoodsize(SIZE) ? __builtin_memmove(DST, SRC, SIZE) \
: memmove$pure(DST, SRC, SIZE))
#undef memcpy
#define memcpy(DST, SRC, SIZE) \
(__memcpy_isgoodsize(SIZE) ? __builtin_memcpy(DST, SRC, SIZE) \
: memmove$pure(DST, SRC, SIZE))
#undef mempcpy
#define mempcpy(DST, SRC, SIZE) \
(__memcpy_isgoodsize(SIZE) ? __builtin_mempcpy(DST, SRC, SIZE) : ({ \
void *DsT = (DST); \
size_t SiZe = (SIZE); \
memmove$pure(DsT, SRC, SiZe); \
(void *)((char *)DsT + SiZe); \
}))
#endif /* __FSANITIZE_ADDRESS__ */
#endif /* __GNUC__ && !__STRICT_ANSI__ */

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@ -8,6 +8,7 @@ LIBC_STR = $(LIBC_STR_A_DEPS) $(LIBC_STR_A)
LIBC_STR_A = o/$(MODE)/libc/str/str.a
LIBC_STR_A_FILES := $(wildcard libc/str/*)
LIBC_STR_A_HDRS = $(filter %.h,$(LIBC_STR_A_FILES))
LIBC_STR_A_INCS = $(filter %.inc,$(LIBC_STR_A_FILES))
LIBC_STR_A_SRCS_A = $(filter %.s,$(LIBC_STR_A_FILES))
LIBC_STR_A_SRCS_S = $(filter %.S,$(LIBC_STR_A_FILES))
LIBC_STR_A_SRCS_C = $(filter %.c,$(LIBC_STR_A_FILES))
@ -49,6 +50,7 @@ o/$(MODE)/libc/str/memmem.o: \
LIBC_STR_LIBS = $(foreach x,$(LIBC_STR_ARTIFACTS),$($(x)))
LIBC_STR_SRCS = $(foreach x,$(LIBC_STR_ARTIFACTS),$($(x)_SRCS))
LIBC_STR_HDRS = $(foreach x,$(LIBC_STR_ARTIFACTS),$($(x)_HDRS))
LIBC_STR_INCS = $(foreach x,$(LIBC_STR_ARTIFACTS),$($(x)_INCS))
LIBC_STR_BINS = $(foreach x,$(LIBC_STR_ARTIFACTS),$($(x)_BINS))
LIBC_STR_CHECKS = $(foreach x,$(LIBC_STR_ARTIFACTS),$($(x)_CHECKS))
LIBC_STR_OBJS = $(foreach x,$(LIBC_STR_ARTIFACTS),$($(x)_OBJS))

69
libc/str/strchr.c Normal file
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@ -0,0 +1,69 @@
/*-*- 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/str/str.h"
noasan static const unsigned char *strchr$x64(const unsigned char *p,
uint64_t c) {
unsigned a, b;
uint64_t w, x, y;
for (c *= 0x0101010101010101;; p += 8) {
w = (uint64_t)p[7] << 070 | (uint64_t)p[6] << 060 | (uint64_t)p[5] << 050 |
(uint64_t)p[4] << 040 | (uint64_t)p[3] << 030 | (uint64_t)p[2] << 020 |
(uint64_t)p[1] << 010 | (uint64_t)p[0] << 000;
if ((x = ~(w ^ c) & ((w ^ c) - 0x0101010101010101) & 0x8080808080808080) |
(y = ~w & (w - 0x0101010101010101) & 0x8080808080808080)) {
if (x) {
a = __builtin_ctzll(x);
if (y) {
b = __builtin_ctzll(y);
if (a <= b) {
return p + (a >> 3);
} else {
return NULL;
}
} else {
return p + (a >> 3);
}
} else {
return NULL;
}
}
}
}
/**
* Returns pointer to first instance of character.
*
* @param s is a NUL-terminated string
* @param c is masked with 255 as byte to search for
* @return pointer to first instance of c or NULL if not found
* noting that if c is NUL we return pointer to terminator
* @asyncsignalsafe
*/
char *strchr(const char *s, int c) {
char *r;
for (c &= 0xff; (uintptr_t)s & 7; ++s) {
if ((*s & 0xff) == c) return s;
if (!*s) return NULL;
}
r = (char *)strchr$x64((const unsigned char *)s, c);
assert(!r || *r || !c);
return r;
}

69
libc/str/strchrnul.c Normal file
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@ -0,0 +1,69 @@
/*-*- 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/str/str.h"
noasan static const unsigned char *strchrnul$x64(const unsigned char *p,
uint64_t c) {
unsigned a, b;
uint64_t w, x, y;
for (c *= 0x0101010101010101;; p += 8) {
w = (uint64_t)p[7] << 070 | (uint64_t)p[6] << 060 | (uint64_t)p[5] << 050 |
(uint64_t)p[4] << 040 | (uint64_t)p[3] << 030 | (uint64_t)p[2] << 020 |
(uint64_t)p[1] << 010 | (uint64_t)p[0] << 000;
if ((x = ~(w ^ c) & ((w ^ c) - 0x0101010101010101) & 0x8080808080808080) |
(y = ~w & (w - 0x0101010101010101) & 0x8080808080808080)) {
if (x) {
a = __builtin_ctzll(x);
if (y) {
b = __builtin_ctzll(y);
if (a <= b) {
return p + (a >> 3);
} else {
return p + (b >> 3);
}
} else {
return p + (a >> 3);
}
} else {
b = __builtin_ctzll(y);
return p + (b >> 3);
}
}
}
}
/**
* Returns pointer to first instance of character.
*
* @param s is a NUL-terminated string
* @param c is masked with 255 as byte to search for
* @return pointer to first instance of c, or pointer to
* NUL terminator if c is not found
*/
char *strchrnul(const char *s, int c) {
char *r;
for (c &= 0xff; (uintptr_t)s & 7; ++s) {
if ((*s & 0xff) == c) return s;
if (!*s) return s;
}
r = (char *)strchrnul$x64((const unsigned char *)s, c);
assert((*r & 0xff) == c || !*r);
return r;
}

View file

@ -18,6 +18,12 @@
*/
#include "libc/str/str.h"
static inline noasan uint64_t UncheckedAlignedRead64(unsigned char *p) {
return (uint64_t)p[7] << 070 | (uint64_t)p[6] << 060 | (uint64_t)p[5] << 050 |
(uint64_t)p[4] << 040 | (uint64_t)p[3] << 030 | (uint64_t)p[2] << 020 |
(uint64_t)p[1] << 010 | (uint64_t)p[0] << 000;
}
/**
* Compares NUL-terminated strings.
*
@ -28,7 +34,25 @@
*/
int strcmp(const char *a, const char *b) {
size_t i = 0;
uint64_t v, w, d;
if (a == b) return 0;
while (a[i] == b[i] && b[i]) ++i;
return (a[i] & 0xff) - (b[i] & 0xff);
if (((uintptr_t)a & 7) == ((uintptr_t)b & 7)) {
for (; (uintptr_t)a & 7; ++i) {
if (a[i] != b[i] || !b[i]) {
return (a[i] & 0xff) - (b[i] & 0xff);
}
}
for (;; i += 8) {
v = UncheckedAlignedRead64(a + i);
w = UncheckedAlignedRead64(b + i);
w = (v ^ w) | (~v & (v - 0x0101010101010101) & 0x8080808080808080);
if (w) {
i += (unsigned)__builtin_ctzll(w) >> 3;
return (a[i] & 0xff) - (b[i] & 0xff);
}
}
} else {
while (a[i] == b[i] && b[i]) ++i;
return (a[i] & 0xff) - (b[i] & 0xff);
}
}

62
libc/str/strcspn-pure.c Normal file
View file

@ -0,0 +1,62 @@
/*-*- 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 2020 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/intrin/pcmpeqb.h"
#include "libc/intrin/pmovmskb.h"
#include "libc/intrin/pshufd.h"
#include "libc/intrin/punpcklbw.h"
#include "libc/intrin/punpcklwd.h"
#include "libc/nexgen32e/hascharacter.internal.h"
#include "libc/str/str.h"
#define V(p) (void *)(p)
/**
* Returns prefix length, consisting of chars not in reject.
* a.k.a. Return index of first byte that's in charset.
*
* @param reject is nul-terminated character set
* @see strspn(), strtok_r()
* @asyncsignalsafe
*/
size_t strcspn$pure(const char *s, const char *reject) {
size_t i, n;
unsigned m;
char cv[16], sv[16];
if ((n = strlen(reject)) < 16) {
memset(sv, 0, 16);
memcpy(sv, reject, n);
for (i = 0;; ++i) {
cv[0] = s[i];
punpcklbw(V(cv), V(cv), V(cv));
punpcklwd(V(cv), V(cv), V(cv));
pshufd(V(cv), V(cv), 0);
pcmpeqb(V(cv), V(cv), V(sv));
if ((m = pmovmskb(V(cv)))) {
break;
}
}
return i;
}
for (i = 0; s[i]; ++i) {
if (HasCharacter(s[i], reject)) {
break;
}
}
return i;
}

View file

@ -16,35 +16,35 @@
TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
PERFORMANCE OF THIS SOFTWARE.
*/
#include "libc/assert.h"
#include "libc/str/str.h"
noasan static const char *strlen$pure$x64(const char *p) {
static noasan size_t strlen$pure$x64(const char *s, size_t i) {
uint64_t w;
const unsigned char *p;
for (;;) {
w = *(uint64_t *)p;
if (~w & (w - 0x0101010101010101) & 0x8080808080808080) {
break;
p = (const unsigned char *)s + i;
w = (uint64_t)p[7] << 070 | (uint64_t)p[6] << 060 | (uint64_t)p[5] << 050 |
(uint64_t)p[4] << 040 | (uint64_t)p[3] << 030 | (uint64_t)p[2] << 020 |
(uint64_t)p[1] << 010 | (uint64_t)p[0] << 000;
if ((w = ~w & (w - 0x0101010101010101) & 0x8080808080808080)) {
return i + ((unsigned)__builtin_ctzll(w) >> 3);
} else {
p += 8;
i += 8;
}
}
return p;
}
/**
* Returns length of NUL-terminated string.
*/
size_t strlen$pure(const char *s) {
const char *p;
p = s;
while ((uintptr_t)p & 7) {
if (*p) {
++p;
} else {
return p - s;
}
size_t i;
for (i = 0; (uintptr_t)(s + i) & 7; ++i) {
if (!s[i]) return i;
}
p = strlen$pure$x64(p);
while (*p) ++p;
return p - s;
i = strlen$pure$x64(s, i);
assert(!i || s[0]);
assert(!s[i]);
return i;
}

57
libc/str/strnlen.c Normal file
View file

@ -0,0 +1,57 @@
/*-*- 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/str/str.h"
static noasan size_t strnlen$x64(const char *s, size_t n, size_t i) {
uint64_t w;
const unsigned char *p;
for (; i + 8 < n; i += 8) {
p = (const unsigned char *)s + i;
w = (uint64_t)p[7] << 070 | (uint64_t)p[6] << 060 | (uint64_t)p[5] << 050 |
(uint64_t)p[4] << 040 | (uint64_t)p[3] << 030 | (uint64_t)p[2] << 020 |
(uint64_t)p[1] << 010 | (uint64_t)p[0] << 000;
if ((w = ~w & (w - 0x0101010101010101) & 0x8080808080808080)) {
i += (unsigned)__builtin_ctzll(w) >> 3;
break;
}
}
return i;
}
/**
* Returns length of NUL-terminated string w/ limit.
*
* @param s is string
* @param n is max length
* @return byte length
* @asyncsignalsafe
*/
size_t strnlen(const char *s, size_t n) {
size_t i;
for (i = 0; (uintptr_t)(s + i) & 7; ++i) {
if (i == n || !s[i]) return i;
}
i = strnlen$x64(s, n, i);
for (;; ++i) {
if (i == n || !s[i]) break;
}
assert(i == n || (i < n && !s[i]));
return i;
}