/src/nspr/pr/src/misc/prlog2.c
Line | Count | Source |
1 | | /* This Source Code Form is subject to the terms of the Mozilla Public |
2 | | * License, v. 2.0. If a copy of the MPL was not distributed with this |
3 | | * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ |
4 | | |
5 | | #include "prbit.h" |
6 | | |
7 | | /* |
8 | | ** Compute the log of the least power of 2 greater than or equal to n |
9 | | */ |
10 | 91 | PR_IMPLEMENT(PRIntn) PR_CeilingLog2(PRUint32 n) { |
11 | 91 | PRIntn log2; |
12 | 91 | PR_CEILING_LOG2(log2, n); |
13 | 91 | return log2; |
14 | 91 | } |
15 | | |
16 | | /* |
17 | | ** Compute the log of the greatest power of 2 less than or equal to n. |
18 | | ** This really just finds the highest set bit in the word. |
19 | | */ |
20 | 0 | PR_IMPLEMENT(PRIntn) PR_FloorLog2(PRUint32 n) { |
21 | 0 | PRIntn log2; |
22 | 0 | PR_FLOOR_LOG2(log2, n); |
23 | 0 | return log2; |
24 | 0 | } |