From 8780f66c3ae1ebe850bfdbf9c2ce2585be836cfe Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Timur=20Krist=C3=B3f?= <timur.kristof@gmail.com>
Date: Thu, 20 Apr 2023 12:35:01 +0200
Subject: [PATCH] nir/opt_dead_cf: Remove if branches with undef condition.
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Treat them as if the undef were false.

Reviewed-by: Marek Olšák <marek.olsak@amd.com>
Reviewed-by: Faith Ekstrand <faith.ekstrand@collabora.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/24792>
---
 src/compiler/nir/nir_opt_dead_cf.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/src/compiler/nir/nir_opt_dead_cf.c b/src/compiler/nir/nir_opt_dead_cf.c
index 352c6f8ff17..45141856057 100644
--- a/src/compiler/nir/nir_opt_dead_cf.c
+++ b/src/compiler/nir/nir_opt_dead_cf.c
@@ -285,6 +285,9 @@ dead_cf_block(nir_block *block)
       if (nir_src_is_const(following_if->condition)) {
          opt_constant_if(following_if, nir_src_as_bool(following_if->condition));
          return true;
+      } else if (nir_src_is_undef(following_if->condition)) {
+         opt_constant_if(following_if, false);
+         return true;
       }
 
       if (node_is_dead(&following_if->cf_node)) {