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