diff options
| -rw-r--r-- | src/malloc/malloc.c | 29 |
1 files changed, 23 insertions, 6 deletions
diff --git a/src/malloc/malloc.c b/src/malloc/malloc.c index 9e05e1d6..0a7d5d85 100644 --- a/src/malloc/malloc.c +++ b/src/malloc/malloc.c @@ -366,15 +366,32 @@ void *malloc(size_t n) return CHUNK_TO_MEM(c); } +static size_t mal0_clear(char *p, size_t pagesz, size_t n) +{ +#ifdef __GNUC__ + typedef uint64_t __attribute__((__may_alias__)) T; +#else + typedef unsigned char T; +#endif + char *pp = p + n; + size_t i = (uintptr_t)pp & (pagesz - 1); + for (;;) { + pp = memset(pp - i, 0, i); + if (pp - p < pagesz) return pp - p; + for (i = pagesz; i; i -= 2*sizeof(T), pp -= 2*sizeof(T)) + if (((T *)pp)[-1] | ((T *)pp)[-2]) + break; + } +} + void *__malloc0(size_t n) { void *p = malloc(n); - if (p && !IS_MMAPPED(MEM_TO_CHUNK(p))) { - size_t *z; - n = (n + sizeof *z - 1)/sizeof *z; - for (z=p; n; n--, z++) if (*z) *z=0; - } - return p; + if (!p || IS_MMAPPED(MEM_TO_CHUNK(p))) + return p; + if (n >= PAGE_SIZE) + n = mal0_clear(p, PAGE_SIZE, n); + return memset(p, 0, n); } void *realloc(void *p, size_t n) |