[Mesa-dev] i965: Improved shader_time accuracy, using send-from-GRF

[Eric Anholt]

I've been experimenting with the simd16 replicated data message
(non-gen7-specific fast clears), and was bothered that shader_time wasn't
noting any time spent in our clear FS currently, so I wasn't totally sure
which apps I should be looking at.

Many apps won't spend any time in the clear FS since they don't clear
color, in which case the FS isn't dispatched.  But for those that do
(like minecraft), it would be nice to see how much is spent clearing.  I
also knew that we were significantly under-counting VS time by not
counting URB payload setup, which I'd worked on a patchset for
previously.

This series fixes those two problems.  Now we know that 7% of non-EOT
instruction time in minecraft is in the clear color setup (wow), and that
VSes are a bit of a bigger deal than we previously knew (36% of minecraft,
23% of ETQW, 7.5% of GLB2.7)

Branch is at shadertime-from-grfs of my tree.