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
