From 3ff698e9fc876b14add8db43cd3c7f74b28f056a Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Timur=20Krist=C3=B3f?= <timur.kristof@gmail.com>
Date: Mon, 25 May 2026 11:56:47 +0200
Subject: [PATCH] ac/nir: When loading an arg, assert that it's used
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To avoid weird crashes caused by trying to load unused attributes.

Signed-off-by: Timur Kristóf <timur.kristof@gmail.com>
Reviewed-by: Natalie Vock <natalie.vock@gmx.de>
Reviewed-by: Samuel Pitoiset <samuel.pitoiset@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/41780>
---
 src/amd/common/nir/ac_nir.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/src/amd/common/nir/ac_nir.c b/src/amd/common/nir/ac_nir.c
index 66c9be306b1..e629a1b1445 100644
--- a/src/amd/common/nir/ac_nir.c
+++ b/src/amd/common/nir/ac_nir.c
@@ -182,6 +182,8 @@ nir_def *
 ac_nir_load_arg_at_offset(nir_builder *b, const struct ac_shader_args *ac_args,
                           struct ac_arg arg, unsigned relative_index)
 {
+   assert(arg.used);
+
    unsigned arg_index = arg.arg_index + relative_index;
    unsigned num_components = ac_args->args[arg_index].size;