tree aac2ab103a79c04a56cf9a802596365b952a3e7c
parent 44660405ea6ce02683617cc483aecc080499aa27
author Sean Risser <srisser@google.com> 1626725539 -0400
committer swiftshader-scoped@luci-project-accounts.iam.gserviceaccount.com <swiftshader-scoped@luci-project-accounts.iam.gserviceaccount.com> 1627927740 +0000

Optimize Lod and Grad texture sampling

If the Lod doesn't vary across any sample, then we can get away with
performing a single texture sample call. The added cost of a reactor If
is balanced by potentially removing 3 calls altogether.

Bug: b/133868964
Bug: b/163791974
Tests: dEQP-VK.texture.subgroup_lod.texelfetch
Tests: dEQP-VK.glsl.texture_functions.texelfetch.*
Tests: dEQP-VK.glsl.texture_functions.texturelod.*
Tests: dEQP-VK.glsl.texture_functions.texturegrad.*

Change-Id: Ib637653f78d3d5aa149352648c710d5f48526ede
Reviewed-on: https://swiftshader-review.googlesource.com/c/SwiftShader/+/55908
Tested-by: Sean Risser <srisser@google.com>
Commit-Queue: Sean Risser <srisser@google.com>
Reviewed-by: Nicolas Capens <nicolascapens@google.com>