From e5d49f662e9e925fa405c3cfb9ffa3e743044dd8 Mon Sep 17 00:00:00 2001
From: wm4 <wm4@nowhere>
Date: Fri, 10 Apr 2020 13:10:18 +0200
Subject: common: fix mp_round_next_power_of_2()
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Who write this dumb shit¹? It didn't handle 1<<31, and was unnecessarily
slow.

¹ it was me
---
 common/common.c | 11 ++++++-----
 1 file changed, 6 insertions(+), 5 deletions(-)

(limited to 'common/common.c')

diff --git a/common/common.c b/common/common.c
index 5068995ded..0552bddda4 100644
--- a/common/common.c
+++ b/common/common.c
@@ -344,9 +344,10 @@ unsigned int mp_log2(uint32_t v)
 //  mp_round_next_power_of_2(UINT32_MAX)    == 0
 uint32_t mp_round_next_power_of_2(uint32_t v)
 {
-    for (int n = 0; n < 30; n++) {
-        if ((1 << n) >= v)
-            return 1 << n;
-    }
-    return 0;
+    if (!v)
+        return 1;
+    if (!(v & (v - 1)))
+        return v;
+    int l = mp_log2(v) + 1;
+    return l == 32 ? 0 : (uint32_t)1 << l;
 }
-- 
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