From e210b79ce3932f7fb1387d68a4cad495b77746f4 Mon Sep 17 00:00:00 2001
From: Ian Romanick <ian.d.romanick@intel.com>
Date: Mon, 31 Mar 2025 11:15:55 -0700
Subject: [PATCH] brw/nir: Lower fsign again after last call to
 brw_nir_optimize

No shader-db or fossil-db changes on any Intel platform.

Fixes: 13332c23 ("intel/brw: Unconditionally run optimizations after nir_opt_uniform_subgroup")
Closes: #12888
Reviewed-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/34251>
---
 src/intel/compiler/brw_nir.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/src/intel/compiler/brw_nir.c b/src/intel/compiler/brw_nir.c
index f7dc469bd46..4b19ed0fbb3 100644
--- a/src/intel/compiler/brw_nir.c
+++ b/src/intel/compiler/brw_nir.c
@@ -1954,6 +1954,13 @@ brw_postprocess_nir(nir_shader *nir, const struct brw_compiler *compiler,
       OPT(nir_lower_subgroups, &subgroups_options);
    }
 
+   /* Run fsign lowering again after the last time brw_nir_optimize is called.
+    * As is the case with conversion lowering (below), brw_nir_optimize can
+    * create additional fsign instructions.
+    */
+   if (OPT(brw_nir_lower_fsign))
+      OPT(nir_opt_dce);
+
    /* Run intel_nir_lower_conversions only after the last time
     * brw_nir_optimize is called. Various optimizations invoked there can
     * rematerialize the conversions that the lowering pass eliminates.