michael@0: /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
michael@0: /* This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0:  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: #include "prbit.h"
michael@0: 
michael@0: /*
michael@0: ** Compute the log of the least power of 2 greater than or equal to n
michael@0: */
michael@0: PR_IMPLEMENT(PRIntn) PR_CeilingLog2(PRUint32 n)
michael@0: {
michael@0:     PRIntn log2;
michael@0:     PR_CEILING_LOG2(log2, n);
michael@0:     return log2;
michael@0: }
michael@0: 
michael@0: /*
michael@0: ** Compute the log of the greatest power of 2 less than or equal to n.
michael@0: ** This really just finds the highest set bit in the word.
michael@0: */
michael@0: PR_IMPLEMENT(PRIntn) PR_FloorLog2(PRUint32 n)
michael@0: {
michael@0:     PRIntn log2;
michael@0:     PR_FLOOR_LOG2(log2, n);
michael@0:     return log2;
michael@0: }