fdo-mirrors/mesa
1
0
Fork 0
mirror of https://gitlab.freedesktop.org/mesa/mesa.git synced 2026-05-08 15:38:09 +02:00
Code Issues Projects Releases Packages Wiki Activity Actions 1

nir: Teach nir_opt_algebraic about adding and subtracting the same thing

Browse source 
This optimizes a + b - b to just a. Modest shader-db results (BDW):

  total instructions in shared programs: 7842452 -> 7841862 (-0.01%)
  instructions in affected programs:     61938 -> 61348 (-0.95%)
  total loops in shared programs:        2131 -> 2131 (0.00%)
  helped:                                263
  HURT:                                  0
  GAINED:                                0
  LOST:                                  0

but the optimization turns

  gl_VertexID - gl_BaseVertexARB

into just a reference to SYSTEM_VALUE_VERTEX_ID_ZERO_BASE, which the
i965 hardware supports natively. That means we can avoid using the
internal vertex buffer for gl_BaseVertexARB in this case.

Reviewed-by: Eduardo Lima Mitev <elima@igalia.com>
Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
Reviewed-by: Matt Turner <mattst88@gmail.com>
This commit is contained in:
Kristian Høgsberg Kristensen 2015-12-14 17:44:23 -08:00
parent cddfc2cefa
commit f9283f2668
1 changed files with 4 additions and 0 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

4
src/glsl/nir/nir_opt_algebraic.py
View file

@ -62,6 +62,10 @@ optimizations = [
(('iadd', ('imul', a, b), ('imul', a, c)), ('imul', a, ('iadd', b, c))),
(('fadd', ('fneg', a), a), 0.0),
(('iadd', ('ineg', a), a), 0),
(('iadd', ('ineg', a), ('iadd', a, b)), b),
(('iadd', a, ('iadd', ('ineg', a), b)), b),
(('fadd', ('fneg', a), ('fadd', a, b)), b),
(('fadd', a, ('fadd', ('fneg', a), b)), b),
(('fmul', a, 0.0), 0.0),
(('imul', a, 0), 0),
(('umul_unorm_4x8', a, 0), 0),