From 0dd50a426e1e3010bb548ae0101a66b734ea4c94 Mon Sep 17 00:00:00 2001
From: Georg Lehmann <dadschoorse@gmail.com>
Date: Thu, 7 May 2026 14:46:48 +0200
Subject: [PATCH] nir: fix fp_math_ctrl in fisnan

Otherwise, nir_opt_algebraic will replace it with false.

Fixes: 63d199a01e8 ("nir: remove special fp_math_ctrl rules")
Reviewed-by: Karol Herbst <kherbst@redhat.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/41420>
---
 src/compiler/nir/nir_builtin_builder.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/compiler/nir/nir_builtin_builder.h b/src/compiler/nir/nir_builtin_builder.h
index 115fb08b5bb..14eb5d28ada 100644
--- a/src/compiler/nir/nir_builtin_builder.h
+++ b/src/compiler/nir/nir_builtin_builder.h
@@ -65,7 +65,7 @@ static inline nir_def *
 nir_fisnan(nir_builder *b, nir_def *x)
 {
    unsigned old_fp_math_ctrl = b->fp_math_ctrl;
-   b->fp_math_ctrl |= nir_fp_exact;
+   b->fp_math_ctrl |= nir_fp_preserve_inf | nir_fp_preserve_nan;
    nir_def *res = nir_fneu(b, x, x);
    b->fp_math_ctrl = old_fp_math_ctrl;
    return res;