Support GC_memalign with alignments greater than HBLKSIZE

Issue #510 (bdwgc).

* allchblk.c (GC_allochblk_nth, GC_allochblk, next_hblk_fits_better,
find_nonbl_hblk): Add align_m1 argument.
* include/private/gc_priv.h (GC_allochblk, GC_alloc_large): Likewise.
* malloc.c (GC_alloc_large): Likewise.
* allchblk.c (GC_allochblk): Check that there is no overflow in
blocks*HBLKSIZE+align_m1; pass align_m1 to GC_allochblk_nth; try
start_list again (with may_split) if non-zero align_m1.
* allchblk.c (ALIGN_PAD_SZ): New macro.
* allchblk.c (next_hblk_fits_better): Define and use next_ofs local
variable; adjust next_hbp passed to GC_is_black_listed().
* allchblk.c (find_nonbl_hblk): Adjust search_end and last_hbp based
on align_m1 value.
* allchblk.c (GC_allochblk_nth): Add assertion that align_m1+1 is
a power of two and that align_m1+1 is 1 or a multiple of HBLKSIZE;
define and use align_ofs local variable; add assertion that last_hbp
(before GC_install_header() call) is multiple of align_m1+1.
* include/gc/gc.h (GC_memalign): Update comment to mention the
restriction on align value (should be a power of two and not less than
size of a pointer).
* include/private/gc_priv.h (GC_allochblk, GC_alloc_large): Update
comment (to mention align_m1 argument).
* include/private/gc_priv.h (GC_generic_malloc_aligned): Declare
function.
* include/private/gcconfig.h [(NACL || I386 && (EMSCRIPTEN || WASI))
&& !HBLKSIZE && !GC_NO_VALLOC] (HBLKSIZE): Do not define (to 65536 or
GETPAGESIZE()); remove TODO item.
* malloc.c (GC_alloc_large): Add alignment to n_blocks value (but not
to GC_large_allocd_bytes); pass align_m1 to GC_allochblk(); add
assertion that result is aligned to align_m1+1.
* malloc.c (GC_alloc_large_and_clear): Pass zero align_m1 to
GC_alloc_large().
* mallocx.c (GC_generic_malloc_ignore_off_page): Likewise.
* malloc.c (GC_generic_malloc_aligned): Move code from
GC_generic_malloc; adjust align_m1 to be either zero or not less than
HBLKSIZE-1, and pass it to GC_alloc_large(); add comment that the
result of GC_oom_fn(lb) might be unaligned.
* malloc.c (GC_generic_malloc): Call GC_generic_malloc_aligned() with
zero align_m1.
* mallocx.c (GC_generic_malloc_ignore_off_page): Expect result of
GC_alloc_large() is unlikely to be NULL.
* mallocx.c (GC_generic_malloc_many): Pass zero align_m1 to
GC_allochblk().
* new_hblk.c (GC_new_hblk): Likewise.
* mallocx.c: Do not include limits.h.
* mallocx.c (GC_memalign): Remove new_lb local variable; define and
use align_m1 local variable; if align is smaller than sizeof(void*) or
is not a power of two than return NULL; call GC_generic_malloc_aligned
and GC_clear_stack (instead of GC_oom_fn() or GC_malloc()) if align or
lb is at least HBLKSIZE/2; replace result%align to result&align_m1;
do not result+=offset if offset is zero.
* new_hblk.c (GC_new_hblk): Expect result of GC_allochblk() is unlikely
to be NULL.
* tests/gctest.c (run_one_test): Call GC_memalign() also for bigger
alignment values (up to HBLKSIZE*4).

1 files changed, 1 insertions, 1 deletions

diff --git a/tests/gctest.c b/tests/gctest.c
index ba60f108..16959648 100644
--- a/tests/gctest.c
+++ b/tests/gctest.c
@@ -1558,7 +1558,7 @@ void run_one_test(void)
           AO_fetch_and_add1(&collectable_count);
 
           /* TODO: GC_memalign and friends are not tested well. */
-          for (i = sizeof(GC_word); i < 512; i *= 2) {
+          for (i = sizeof(GC_word); i <= HBLKSIZE * 4; i *= 2) {
             p = GC_memalign(i, 17);
             CHECK_OUT_OF_MEMORY(p);
             AO_fetch_and_add1(&collectable_count);