vc4: Improve interleaving of texture coordinates vs results

Graphics / Mesa 3D Graphics Library / Mesa - Eric Anholt [anholt.net] - 30 November 2016 21:58 UTC

The latency_between was trying to handle the delay between the coordinate write ("before") and the corresponding sample read ("after"), but we were handing in the two instructions swapped.

This meant that we tried to fit things between a tex_s and its *preceding* tex_result. This made us only interleave normal texture coordinates by accident, and pessimized UBO reads by pushing the tex_result collection earlier until there was nothing but it (and then its preceding coordinate setup) left.

In addition to latency reduction, things end up packing better (probably due to reduced live ranges of the texture results):

total instructions in shared programs: 98121 -> 94775 (-3.41%) instructions in affected programs: 91196 -> 87850 (-3.67%)

3DMMES performance +1.15569% +/- 0.124714% (n=8,10)

d182740 vc4: Improve interleaving of texture coordinates vs results.
src/gallium/drivers/vc4/vc4_qir_schedule.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)

Upstream: cgit.freedesktop.org

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