SDL: gen_audio_resampler_filter.c: Precalculate loop-invariant bessel(beta).

SDL Commits
1 
From 5968f3d828aaf28a28763fce794020fc8239a35a Mon Sep 17 00:00:00 2001
From: "Ryan C. Gordon" <[EMAIL REDACTED]>
Date: Thu, 26 May 2022 10:44:01 -0400
Subject: [PATCH] gen_audio_resampler_filter.c: Precalculate loop-invariant
 bessel(beta).

Minor optimization in offline code.
---
 build-scripts/gen_audio_resampler_filter.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/build-scripts/gen_audio_resampler_filter.c b/build-scripts/gen_audio_resampler_filter.c
index 4a343fb639c..99d77957ebb 100644
--- a/build-scripts/gen_audio_resampler_filter.c
+++ b/build-scripts/gen_audio_resampler_filter.c
@@ -74,11 +74,12 @@ kaiser_and_sinc(float *table, float *diffs, const int tablelen, const double bet
 {
     const int lenm1 = tablelen - 1;
     const int lenm1div2 = lenm1 / 2;
+    const double bessel_beta = bessel(beta);
     int i;
 
     table[0] = 1.0f;
     for (i = 1; i < tablelen; i++) {
-        const double kaiser = bessel(beta * sqrt(1.0 - pow(((i - lenm1) / 2.0) / lenm1div2, 2.0))) / bessel(beta);
+        const double kaiser = bessel(beta * sqrt(1.0 - pow(((i - lenm1) / 2.0) / lenm1div2, 2.0))) / bessel_beta;
         table[tablelen - i] = (float) kaiser;
     }