diff options
| -rw-r--r-- | src/shared/mem.c | 36 |
1 files changed, 23 insertions, 13 deletions
diff --git a/src/shared/mem.c b/src/shared/mem.c index 49b3588..e3279f6 100644 --- a/src/shared/mem.c +++ b/src/shared/mem.c @@ -1,6 +1,9 @@ #include <shared/mem.h> #include <stdint.h> +union dualptr_const { const uintptr_t *w; const char *c; uintptr_t u; }; +union dualptr { uintptr_t *w; char *c; uintptr_t u; }; + void *memchr(const void *s, int c, size_t n) { const unsigned char *s2 = s; for (size_t i = 0; i < n; i++) { @@ -22,25 +25,32 @@ int memcmp(const void *s1, const void *s2, size_t n) { } void *memcpy(void *dest, const void *src, size_t n) { - const uint32_t *s32 = src; - uint32_t *d32 = dest; - while (n >= 4) { - *d32++ = *s32++; - n -= 4; - } + // TODO erms, rep movsb + union dualptr_const s = {.c = src}; + union dualptr d = {.c = dest}; - const char *s8 = (void*)s32; - char *d8 = (void*)d32; - while (n-- != 0) - *d8++ = *s8++; + for (; (d.u & 7) && n != 0; n--) + *(d.c)++ = *(s.c)++; + while (n >= sizeof(uintptr_t)) { + *(d.w)++ = *(s.w)++; + n -= sizeof(uintptr_t); + } + while (n-- != 0) + *(d.c)++ = *(s.c)++; return dest; } void *memset(void *s, int c, size_t n) { - uint8_t *s2 = s; - for (size_t i = 0; i < n; i++) - s2[i] = c; + union dualptr d = {.c = s}; + + uintptr_t fill = (c & 0xff) * 0x0101010101010101; + while (n >= sizeof(uintptr_t)) { + *(d.w)++ = fill; + n -= sizeof(uintptr_t); + } + while (n-- != 0) + *(d.c)++ = c; return s; } |