diff options
| -rw-r--r-- | ChangeLog | 5 | ||||
| -rw-r--r-- | malloc/obstack.c | 14 | ||||
| -rw-r--r-- | malloc/tst-obstack.c | 54 |
3 files changed, 69 insertions, 4 deletions
@@ -1,5 +1,10 @@ 2000-10-24 Ulrich Drepper <drepper@redhat.com> + * malloc/obstack.c (_obstack_newchunk): Correctly align first returned + block. + * malloc/tst-obstack.c: New file. + Patch and test case by Alexandre Duret-Lutz <duret_g@epita.fr>. + Complete revamp of the reference counter handling. * include/link.h (struct link_map): Add l_idx field. * elf/dl-close.c: Handle decrementing of reference counters more diff --git a/malloc/obstack.c b/malloc/obstack.c index 38fc02faed..6b32678b56 100644 --- a/malloc/obstack.c +++ b/malloc/obstack.c @@ -282,9 +282,10 @@ _obstack_newchunk (h, length) register long obj_size = h->next_free - h->object_base; register long i; long already; + char *object_base; /* Compute size for new chunk. */ - new_size = (obj_size + length) + (obj_size >> 3) + 100; + new_size = (obj_size + length) + (obj_size >> 3) + h->alignment_mask + 100; if (new_size < h->chunk_size) new_size = h->chunk_size; @@ -296,6 +297,11 @@ _obstack_newchunk (h, length) new_chunk->prev = old_chunk; new_chunk->limit = h->chunk_limit = (char *) new_chunk + new_size; + /* Compute an aligned object_base in the new chunk */ + object_base = + __INT_TO_PTR ((__PTR_TO_INT (new_chunk->contents) + h->alignment_mask) + & ~ (h->alignment_mask)); + /* Move the existing object to the new chunk. Word at a time is fast and is safe if the object is sufficiently aligned. */ @@ -303,7 +309,7 @@ _obstack_newchunk (h, length) { for (i = obj_size / sizeof (COPYING_UNIT) - 1; i >= 0; i--) - ((COPYING_UNIT *)new_chunk->contents)[i] + ((COPYING_UNIT *)object_base)[i] = ((COPYING_UNIT *)h->object_base)[i]; /* We used to copy the odd few remaining bytes as one extra COPYING_UNIT, but that can cross a page boundary on a machine @@ -314,7 +320,7 @@ _obstack_newchunk (h, length) already = 0; /* Copy remaining bytes one by one. */ for (i = already; i < obj_size; i++) - new_chunk->contents[i] = h->object_base[i]; + object_base[i] = h->object_base[i]; /* If the object just copied was the only data in OLD_CHUNK, free that chunk and remove it from the chain. @@ -325,7 +331,7 @@ _obstack_newchunk (h, length) CALL_FREEFUN (h, old_chunk); } - h->object_base = new_chunk->contents; + h->object_base = object_base; h->next_free = h->object_base + obj_size; /* The new chunk certainly contains no empty object yet. */ h->maybe_empty_object = 0; diff --git a/malloc/tst-obstack.c b/malloc/tst-obstack.c new file mode 100644 index 0000000000..bd00a0ab7b --- /dev/null +++ b/malloc/tst-obstack.c @@ -0,0 +1,54 @@ +/* Test case by Alexandre Duret-Lutz <duret_g@epita.fr>. */ +#include <obstack.h> +#include <stdint.h> +#include <stdio.h> +#include <stdlib.h> + +#define obstack_chunk_alloc verbose_malloc +#define obstack_chunk_free verbose_free +#define ALIGN_BOUNDARY 64 +#define ALIGN_MASK (ALIGN_BOUNDARY - 1) +#define OBJECT_SIZE 1000 + +static void * +verbose_malloc (size_t size) +{ + void *buf = malloc (size); + printf ("malloc (%u) => %p\n", size, buf); + return buf; +} + +static void +verbose_free (void *buf) +{ + free (buf); + printf ("free (%p)\n", buf); +} + +int +main (void) +{ + struct obstack obs; + int i; + int result = 0; + + obstack_init (&obs); + obstack_alignment_mask (&obs) = ALIGN_MASK; + /* finish an empty object to take alignment into account */ + obstack_finish (&obs); + + /* let's allocate some objects and print their addresses */ + for (i = 15; i > 0; --i) + { + void *obj = obstack_alloc (&obs, OBJECT_SIZE); + + printf ("obstack_alloc (%u) => %p \t%s\n", OBJECT_SIZE, obj, + ((uintptr_t) obj & ALIGN_MASK) ? "(not aligned)" : ""); + result |= ((uintptr_t) obj & ALIGN_MASK) != 0; + } + + /* clean up */ + obstack_free (&obs, 0); + + return result; +} |