i965/fs: Fix vgrf0 live interval when no interpolation was done.
authorEric Anholt <eric@anholt.net>
Wed, 26 Mar 2014 17:06:53 +0000 (10:06 -0700)
committerEric Anholt <eric@anholt.net>
Tue, 8 Apr 2014 07:59:48 +0000 (00:59 -0700)
commitcaa2605db52da7303c4571bddc424a613786f56f
tree0b99b40cd56e645cdecc747d225ce20e4e9dbf24
parentcf40ebacb113a370c1b2445e881f8dc440a7d8f3
i965/fs: Fix vgrf0 live interval when no interpolation was done.

When you've got a simple solid-color shader that doesn't generate
pixel_x/y interpolation, we were deciding that the first vgrf was both the
undefined pixel_x and pixel_y, and extending its live interval to avoid
the stride problem.  That tricked other optimization that tries to see if
a particular instruction is the last use of a variable.

Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
src/mesa/drivers/dri/i965/brw_fs_live_variables.cpp