Re: [Mesa-dev] [PATCH] i965: Fix computation of abs(-x) in FS

2011-10-10 Thread Eric Anholt
On Fri, 7 Oct 2011 12:25:55 -0700, Paul Berry wrote: > When updating a register reference to reflect the fact that we were > taking its absolute value, the fragment shader back-end failed to > clear the negate flag, resulting in abs(-x) getting computed as > -abs(x). > > I also found (and fixed)

[Mesa-dev] [PATCH] i965: Fix computation of abs(-x) in FS

2011-10-07 Thread Paul Berry
When updating a register reference to reflect the fact that we were taking its absolute value, the fragment shader back-end failed to clear the negate flag, resulting in abs(-x) getting computed as -abs(x). I also found (and fixed) a similar problem in brw_eu.h, but I'm not aware of an actual mani