From 47e7cd268c1ee137448a09dc94e36202f2519431 Mon Sep 17 00:00:00 2001
From: Alyssa Rosenzweig <alyssa@rosenzweig.io>
Date: Thu, 29 Aug 2024 19:23:32 -0400
Subject: [PATCH] nir: negate an expression in atan

we're going to fix up the sign immediately anyway.

Signed-off-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>
Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/30934>
---
 src/compiler/nir/nir_builtin_builder.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/compiler/nir/nir_builtin_builder.c b/src/compiler/nir/nir_builtin_builder.c
index 73127a69e00..8def7cbfad3 100644
--- a/src/compiler/nir/nir_builtin_builder.c
+++ b/src/compiler/nir/nir_builtin_builder.c
@@ -203,7 +203,7 @@ nir_atan(nir_builder *b, nir_def *y_over_x)
 
    /* range-reduction fixup */
    tmp = nir_bcsel(b, nir_flt(b, one, abs_y_over_x),
-                   nir_fsub_imm(b, M_PI_2, tmp), tmp);
+                   nir_fadd_imm(b, tmp, -M_PI_2), tmp);
 
    /* sign fixup */
    nir_def *result = nir_copysign(b, tmp, y_over_x);