tree 9eef817405bf8ae60a1dd812d9617c1933914938
parent 205ddee16e5f6fe673e2fdb64510034ce4c9ad03
author Alexis Hetu <sugoi@google.com> 1645568173 -0500
committer Alexis Hétu <sugoi@google.com> 1648227208 +0000

VK_EXT_shader_demote_to_helper_invocation support

This extension adds Vulkan support for the
SPV_EXT_demote_to_helper_invocation SPIR-V extension. That
SPIR-V extension provides a new instruction
OpDemoteToHelperInvocationEXT allowing shaders to “demote”
a fragment shader invocation to behave like a helper
invocation for its duration. The demoted invocation will
have no further side effects and will not output to the
framebuffer, but remains active and can participate in
computing derivatives and in group operations. This is a
better match for the “discard” instruction in HLSL.

Tests: dEQP-VK.rasterization.frag_side_effects.*.demote
Tests: dEQP-VK.glsl.demote.*
Tests: dEQP-VK.glsl.discard.*
Bug: b/204502919
Change-Id: I2a1d5ab2cda5a4f57ef9798861e3ea915c39c20c
Reviewed-on: https://swiftshader-review.googlesource.com/c/SwiftShader/+/64408
Reviewed-by: Nicolas Capens <nicolascapens@google.com>
Tested-by: Alexis Hétu <sugoi@google.com>