nsprpub/pr/src/misc/prlog2.c@6474c204b198 (annotated)
nsprpub/pr/src/misc/prlog2.c
Wed, 31 Dec 2014 06:09:35 +0100
- author
- Michael Schloh von Bennewitz <michael@schloh.com>
- date
- Wed, 31 Dec 2014 06:09:35 +0100
- changeset 0
- 6474c204b198
- permissions
- -rw-r--r--
Cloned upstream origin tor-browser at tor-browser-31.3.0esr-4.5-1-build1
revision ID fc1c9ff7c1b2defdbc039f12214767608f46423f for hacking purpose.
| michael@0 | 1 | /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ |
| michael@0 | 2 | /* This Source Code Form is subject to the terms of the Mozilla Public |
| michael@0 | 3 | * License, v. 2.0. If a copy of the MPL was not distributed with this |
| michael@0 | 4 | * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ |
| michael@0 | 5 | |
| michael@0 | 6 | #include "prbit.h" |
| michael@0 | 7 | |
| michael@0 | 8 | /* |
| michael@0 | 9 | ** Compute the log of the least power of 2 greater than or equal to n |
| michael@0 | 10 | */ |
| michael@0 | 11 | PR_IMPLEMENT(PRIntn) PR_CeilingLog2(PRUint32 n) |
| michael@0 | 12 | { |
| michael@0 | 13 | PRIntn log2; |
| michael@0 | 14 | PR_CEILING_LOG2(log2, n); |
| michael@0 | 15 | return log2; |
| michael@0 | 16 | } |
| michael@0 | 17 | |
| michael@0 | 18 | /* |
| michael@0 | 19 | ** Compute the log of the greatest power of 2 less than or equal to n. |
| michael@0 | 20 | ** This really just finds the highest set bit in the word. |
| michael@0 | 21 | */ |
| michael@0 | 22 | PR_IMPLEMENT(PRIntn) PR_FloorLog2(PRUint32 n) |
| michael@0 | 23 | { |
| michael@0 | 24 | PRIntn log2; |
| michael@0 | 25 | PR_FLOOR_LOG2(log2, n); |
| michael@0 | 26 | return log2; |
| michael@0 | 27 | } |
