Add memcheck support for the IROps added in VEX r2631.
Adapt vbit-tester.
Patch by Maran Pakkirisamy (maranp@linux.vnet.ibm.com).
Part of fixing BZ 307113.


git-svn-id: svn://svn.valgrind.org/valgrind/trunk@13224 a5019735-40e9-0310-863c-91ae7b9d1cf9
Avoid to record execontext used for origin tracking when --trac-origins=no
All calls to VG_(unknown_SP_update) were recording an execontext
of one IP, useful only for track origin.
This patch implements splits VG_(unknown_SP_update) 
in two different functions VG_(unknown_SP_update_w_ECU)
(doing origin tracking) and VG_(unknown_SP_update)  (not doing origin tracking).




git-svn-id: svn://svn.valgrind.org/valgrind/trunk@13225 a5019735-40e9-0310-863c-91ae7b9d1cf9
no recording of execontext for track origin in brk/signal stack when track-origin=no




git-svn-id: svn://svn.valgrind.org/valgrind/trunk@13226 a5019735-40e9-0310-863c-91ae7b9d1cf9
Comment only changes



git-svn-id: svn://svn.valgrind.org/valgrind/trunk@13227 a5019735-40e9-0310-863c-91ae7b9d1cf9