target-i386: fix cmpxchg instruction emulation
commitabf80f880410ebbdd01a289c41c87153802fe900
authorAndreas Gustafsson <gson@gson.org>
Sun, 11 Dec 2011 20:46:32 +0000 (12 00:46 +0400)
committerJustin M. Forbes <jforbes@redhat.com>
Tue, 10 Jan 2012 15:31:37 +0000 (10 09:31 -0600)
tree7bdcaccc681e11e2a2d7786de03791f50ec34004
parent3d3ec7b809b91f2a71fb78fc6b5b079963383243
target-i386: fix cmpxchg instruction emulation

When the i386 cmpxchg instruction is executed with a memory operand
and the comparison result is "unequal", do the memory write before
changing the accumulator instead of the other way around, because
otherwise the new accumulator value will incorrectly be used in the
comparison when the instruction is restarted after a page fault.

This bug was originally reported on 2010-04-25 as
https://bugs.launchpad.net/qemu/+bug/569760

Signed-off-by: Andreas Gustafsson <gson@gson.org>
target-i386/translate.c