From 640a5e28fddc03248106aa171c7f10b7781e20d5 Mon Sep 17 00:00:00 2001
From: Connor Abbott <cwabbott0@gmail.com>
Date: Mon, 3 Mar 2025 19:58:42 -0500
Subject: [PATCH] compiler/shader_info: Better document require_full_quads

Reviewed-by: Danylo Piliaiev <dpiliaiev@igalia.com>
Reviewed-by: Rob Clark <robdclark@chromium.org>
Reviewed-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/33862>
---
 src/compiler/shader_info.h | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/src/compiler/shader_info.h b/src/compiler/shader_info.h
index aa09ad9442e..899917d38bb 100644
--- a/src/compiler/shader_info.h
+++ b/src/compiler/shader_info.h
@@ -343,7 +343,11 @@ typedef struct shader_info {
          bool color_is_dual_source:1;
 
          /**
-          * True if this fragment shader requires full quad invocations.
+          * True if this fragment shader requires full quad invocations. This
+          * forces the shader to always behave as-if quad groups start with
+          * four active invocations, even if there are no derivatives or quad
+          * operations. Because helper invocations cannot have side effects,
+          * this mainly impacts subgroup operations such as ballot().
           */
          bool require_full_quads:1;