From 5b10b24044b3350a19ab3d3c0b37b5e9c12365b1 Mon Sep 17 00:00:00 2001 From: Mattias Andrée Date: Sun, 13 Mar 2016 23:54:56 +0100 Subject: Multiple changes: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 1) Compile test with -O0, it takes too long otherwise. 2) Add error codes: ZERROR_0_POW_0, ZERROR_0_DIV_0, ZERROR_DIV_0, ZERROR_NEGATIVE. 3) Add workaround for a bug in clang (src/allocator.c). 4) Cleanups. 5) Minor optimisations. 6) Add inclusion guard for zahl.h. Signed-off-by: Mattias Andrée --- src/allocator.c | 48 ++++++++++++++++++++++++++++++++++-------------- 1 file changed, 34 insertions(+), 14 deletions(-) (limited to 'src/allocator.c') diff --git a/src/allocator.c b/src/allocator.c index 33c8677..41ce9ed 100644 --- a/src/allocator.c +++ b/src/allocator.c @@ -1,27 +1,47 @@ /* See LICENSE file for copyright and license details. */ #include "internals.h" +#include + + +/* Find r such that r is a minimal power of 2 ≥ n. */ +#define NEXT_2POW(n)\ + do if (likely((n & (~n + 1)) != n)) {\ + size_t x;\ + n |= n >> 1;\ + n |= n >> 2;\ + n |= n >> 4;\ + for (i = sizeof(n), x = 8; i; i >>= 1, x <<= 1)\ + n |= n >> x;\ + n += 1;\ + } while (0) + + +#if defined(__clang__) +static inline __attribute__((optnone)) size_t +clang_warkaround_next_2pow(size_t need) +{ + size_t i; + NEXT_2POW(need); + return need; +} +#endif void libzahl_realloc(z_t a, size_t need) { - size_t i, x; + size_t i; zahl_char_t *new; - /* Find n such that n is a minimal power of 2 ≥ need. */ - if ((need & (~need + 1)) != need) { - need |= need >> 1; - need |= need >> 2; - need |= need >> 4; - for (i = sizeof(need), x = 8; i; i >>= 1, x <<= 1) - need |= need >> x; - need += 1; - } +#if defined(__clang__) + need = clang_warkaround_next_2pow(need); +#else + NEXT_2POW(need); +#endif - for (i = 0, x = need; x; x >>= 1) - i += 1; + i = libzahl_msb_nz_zu(need); - if (libzahl_pool_n[i]) { + if (likely(libzahl_pool_n[i])) { libzahl_pool_n[i]--; new = libzahl_pool[i][libzahl_pool_n[i]]; zmemcpy(new, a->chars, a->alloced); @@ -32,7 +52,7 @@ libzahl_realloc(z_t a, size_t need) if (!a->chars) { if (!errno) /* sigh... */ errno = ENOMEM; - FAILURE(errno); + libzahl_failure(errno); } } a->alloced = need; -- cgit v1.2.3-70-g09d2