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authorOndřej Bílka <neleai@seznam.cz>2014-02-26 13:13:09 +0100
committerOndřej Bílka <neleai@seznam.cz>2014-02-26 13:15:33 +0100
commit4248f0da6ff9e7dd63464cdecec2dec332dfc2f0 (patch)
tree1f645ac4c027603f3535fd36a6cd38cb63375169
parentade40b10ff5fa59a318cf55b9d8414b758e8df78 (diff)
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Simplify calloc implementation.
To make future improvements of allocator simpler we could for now calloc just call malloc and memset. With that we could omit a changes that would duplicate malloc changes anyway.
-rw-r--r--ChangeLog4
-rw-r--r--malloc/malloc.c115
2 files changed, 10 insertions, 109 deletions
diff --git a/ChangeLog b/ChangeLog
index e6246ea..beb3598 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,7 @@
+2014-02-26 Ondřej Bílka <neleai@seznam.cz>
+
+ * malloc/malloc.c (__libc_calloc): Simplify implementation.
+
2014-02-25 Carlos O'Donell <carlos@redhat.com>
[BZ #16632]
diff --git a/malloc/malloc.c b/malloc/malloc.c
index 9a45707..74ad92d 100644
--- a/malloc/malloc.c
+++ b/malloc/malloc.c
@@ -3141,13 +3141,8 @@ __libc_pvalloc (size_t bytes)
void *
__libc_calloc (size_t n, size_t elem_size)
{
- mstate av;
- mchunkptr oldtop, p;
- INTERNAL_SIZE_T bytes, sz, csz, oldtopsize;
+ INTERNAL_SIZE_T bytes;
void *mem;
- unsigned long clearsize;
- unsigned long nclears;
- INTERNAL_SIZE_T *d;
/* size_t is unsigned so the behavior on overflow is defined. */
bytes = n * elem_size;
@@ -3166,113 +3161,15 @@ __libc_calloc (size_t n, size_t elem_size)
atomic_forced_read (__malloc_hook);
if (__builtin_expect (hook != NULL, 0))
{
- sz = bytes;
- mem = (*hook)(sz, RETURN_ADDRESS (0));
- if (mem == 0)
- return 0;
-
- return memset (mem, 0, sz);
- }
-
- sz = bytes;
-
- arena_get (av, sz);
- if (!av)
- return 0;
-
- /* Check if we hand out the top chunk, in which case there may be no
- need to clear. */
-#if MORECORE_CLEARS
- oldtop = top (av);
- oldtopsize = chunksize (top (av));
-# if MORECORE_CLEARS < 2
- /* Only newly allocated memory is guaranteed to be cleared. */
- if (av == &main_arena &&
- oldtopsize < mp_.sbrk_base + av->max_system_mem - (char *) oldtop)
- oldtopsize = (mp_.sbrk_base + av->max_system_mem - (char *) oldtop);
-# endif
- if (av != &main_arena)
- {
- heap_info *heap = heap_for_ptr (oldtop);
- if (oldtopsize < (char *) heap + heap->mprotect_size - (char *) oldtop)
- oldtopsize = (char *) heap + heap->mprotect_size - (char *) oldtop;
- }
-#endif
- mem = _int_malloc (av, sz);
-
-
- assert (!mem || chunk_is_mmapped (mem2chunk (mem)) ||
- av == arena_for_chunk (mem2chunk (mem)));
-
- if (mem == 0)
- {
- LIBC_PROBE (memory_calloc_retry, 1, sz);
- av = arena_get_retry (av, sz);
- if (__builtin_expect (av != NULL, 1))
- {
- mem = _int_malloc (av, sz);
- (void) mutex_unlock (&av->mutex);
- }
- if (mem == 0)
- return 0;
+ mem = (*hook)(bytes, RETURN_ADDRESS (0));
}
else
- (void) mutex_unlock (&av->mutex);
- p = mem2chunk (mem);
-
- /* Two optional cases in which clearing not necessary */
- if (chunk_is_mmapped (p))
- {
- if (__builtin_expect (perturb_byte, 0))
- return memset (mem, 0, sz);
-
- return mem;
- }
+ mem = __libc_malloc (bytes);
- csz = chunksize (p);
-
-#if MORECORE_CLEARS
- if (perturb_byte == 0 && (p == oldtop && csz > oldtopsize))
- {
- /* clear only the bytes from non-freshly-sbrked memory */
- csz = oldtopsize;
- }
-#endif
-
- /* Unroll clear of <= 36 bytes (72 if 8byte sizes). We know that
- contents have an odd number of INTERNAL_SIZE_T-sized words;
- minimally 3. */
- d = (INTERNAL_SIZE_T *) mem;
- clearsize = csz - SIZE_SZ;
- nclears = clearsize / sizeof (INTERNAL_SIZE_T);
- assert (nclears >= 3);
-
- if (nclears > 9)
- return memset (d, 0, clearsize);
-
- else
- {
- *(d + 0) = 0;
- *(d + 1) = 0;
- *(d + 2) = 0;
- if (nclears > 4)
- {
- *(d + 3) = 0;
- *(d + 4) = 0;
- if (nclears > 6)
- {
- *(d + 5) = 0;
- *(d + 6) = 0;
- if (nclears > 8)
- {
- *(d + 7) = 0;
- *(d + 8) = 0;
- }
- }
- }
- }
+ if (mem == 0)
+ return 0;
- return mem;
+ return memset (mem, 0, bytes);
}
/*