The value of STATE_PRIV is captured by the 1st level trap handler, and
passed on to the second level trap handler. The value is to be restored
before exit. However it is possible for the value of
STATE_PRIV.BARRIER_COMPLETE to change while the wave is in the trap
handler (all the other waves in the workgroup has signaled the
work-gropu barrier), and in this case restoring STATE_PRIV in full would
result in STATE_PRIV.BARRIER_COMPLETE to be cleared.
Restore every bits of STATE_PRIV except for BARRIER_COMPLETE before
return to prevent this race.
Change-Id: I76c875bced7d23c58670b28f257d22c933f99fc5
Signed-off-by: Chris Freehill <cfreehil@amd.com>
Lancelot SIX
9e625307d2