i965: Fix regs read for FS_OPCODE_INTERP_PER_SLOT_OFFSET
authorChris Forbes <chrisf@ijw.co.nz>
Sat, 6 Dec 2014 21:12:36 +0000 (10:12 +1300)
committerChris Forbes <chrisf@ijw.co.nz>
Sat, 6 Dec 2014 21:29:26 +0000 (10:29 +1300)
commit092c73a7c32b240a26ffeab2ee475f6d590540b2
treeddd798ddc2a142932214726a4e24d244794c57f6
parent680f72d6f2259a1dd382a1876a594b407f933278
i965: Fix regs read for FS_OPCODE_INTERP_PER_SLOT_OFFSET

Dead code elimination was eating the Y offset.

Fixes the piglit test:
spec/ARB_gpu_shader5/arb_gpu_shader5-interpolateAtOffset-nonconst

Signed-off-by: Chris Forbes <chrisf@ijw.co.nz>
Reviewed-by: Jason Ekstrand <jason.ekstrand@intel.com>
src/mesa/drivers/dri/i965/brw_fs.cpp