https://bugs.freedesktop.org/show_bug.cgi?id=89944
Sami Liedes sami.liedes@iki.fi changed:
What |Removed |Added ---------------------------------------------------------------------------- CC| |kenneth@whitecape.org
--- Comment #3 from Sami Liedes sami.liedes@iki.fi --- I bisected this down to this commit:
------------------------------------------------------------ commit 30f51f1a1a70bc838d5bed449daff0dd9f2e8ef2 Author: Kenneth Graunke kenneth@whitecape.org Date: Wed Oct 22 20:48:21 2014 -0700
glsl: Optimize "if (cond) discard;" to a conditional discard.
st_glsl_to_tgsi and ir_to_mesa have handled conditional discards for a long time; the previous patch added that capability to i965.
i965 (Haswell) shader-db stats:
Without NIR: total instructions in shared programs: 5792133 -> 5776360 (-0.27%) instructions in affected programs: 737585 -> 721812 (-2.14%) helped: 6300 HURT: 68 GAINED: 2
With NIR: total instructions in shared programs: 5787538 -> 5769569 (-0.31%) instructions in affected programs: 767843 -> 749874 (-2.34%) helped: 6522 HURT: 35 GAINED: 6
Signed-off-by: Kenneth Graunke kenneth@whitecape.org Reviewed-by: Connor Abbott cwabbott0@gmail.com Reviewed-by: Matt Turner mattst88@gmail.com Reviewed-by: Eric Anholt eric@anholt.net ------------------------------------------------------------
I can also confirm that reverting that commit on top of recent HEAD (4deca127) fixes the issue.
I can attach R600_DEBUG=ps,gs,vs output from the offending commit and its parent if you think comparing them is of any use.