Big overhaul of the allocator. Much of the structure is the same, but
lots of the details changed. Made the following generalisations:
- Recast everything to be entirely terms of bytes, instead of a mixture
of (32-bit) words and bytes. This is a bit easier to understand, and
made the following generalisations possible...
- Almost 64-bit clean; no longer assuming 32-bit words/pointers. Only
(I think) non-64-bit clean part is that VG_(malloc)() et al take an
Int as the size arg, and size_t is 64-bits on 64-bit machines.
- Made the alignment of blocks returned by malloc() et al completely
controlled by a single value, VG_MIN_MALLOC_SZB. (Previously there
were various magic numbers and assumptions about block alignment
scattered throughout.) I tested this, all the regression tests pass
with VG_MIN_MALLOC_SZB of 4, 8, 16, 32, 64. One thing required for
this was to make redzones elastic; the asked-for redzone size is now
the minimum size; it will use bigger ones if necessary to get the
required alignment.
Some other specific changes:
- Made use of types a bit more; ie. actually using the type 'Block',
rather than just having everything as arrays of words, so that should
be a bit safer.
- Removed the a->rz_check field, which was redundant wrt. a->clientmem.
- Fixed up the decision about which list to use so the 4 lists which
weren't ever being used now are -- the problem was that this hasn't
been properly updated when alignment changed from 4 to 8 bytes.
- Added a regression test for memalign() and posix_memalign().
memalign() was aborting if passed a bad alignment argument.
- Added some high-level comments in various places, explaining how the
damn thing works.
git-svn-id: svn://svn.valgrind.org/valgrind/trunk@2579 a5019735-40e9-0310-863c-91ae7b9d1cf9
diff --git a/coregrind/vg_include.h b/coregrind/vg_include.h
index 960aac5..f19a1ac 100644
--- a/coregrind/vg_include.h
+++ b/coregrind/vg_include.h
@@ -365,6 +365,14 @@
#define VG_AR_ERRORS 7
#define VG_AR_TRANSIENT 8
+// This is both the minimum payload size of a malloc'd block, and its
+// minimum alignment. Must be a power of 2 greater than 4, and should be
+// greater than 8.
+#define VG_MIN_MALLOC_SZB 8
+
+// Round-up size for --sloppy-malloc=yes.
+#define VG_SLOPPY_MALLOC_SZB 4
+
extern void* VG_(arena_malloc) ( ArenaId arena, Int nbytes );
extern void VG_(arena_free) ( ArenaId arena, void* ptr );
extern void* VG_(arena_calloc) ( ArenaId arena, Int alignment,