1010662326b9c43c703725f933e95e0897f8a6bddGlenn Kasten/* 2010662326b9c43c703725f933e95e0897f8a6bddGlenn Kasten * Copyright (C) 2012 The Android Open Source Project 3010662326b9c43c703725f933e95e0897f8a6bddGlenn Kasten * 4010662326b9c43c703725f933e95e0897f8a6bddGlenn Kasten * Licensed under the Apache License, Version 2.0 (the "License"); 5010662326b9c43c703725f933e95e0897f8a6bddGlenn Kasten * you may not use this file except in compliance with the License. 6010662326b9c43c703725f933e95e0897f8a6bddGlenn Kasten * You may obtain a copy of the License at 7010662326b9c43c703725f933e95e0897f8a6bddGlenn Kasten * 8010662326b9c43c703725f933e95e0897f8a6bddGlenn Kasten * http://www.apache.org/licenses/LICENSE-2.0 9010662326b9c43c703725f933e95e0897f8a6bddGlenn Kasten * 10010662326b9c43c703725f933e95e0897f8a6bddGlenn Kasten * Unless required by applicable law or agreed to in writing, software 11010662326b9c43c703725f933e95e0897f8a6bddGlenn Kasten * distributed under the License is distributed on an "AS IS" BASIS, 12010662326b9c43c703725f933e95e0897f8a6bddGlenn Kasten * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13010662326b9c43c703725f933e95e0897f8a6bddGlenn Kasten * See the License for the specific language governing permissions and 14010662326b9c43c703725f933e95e0897f8a6bddGlenn Kasten * limitations under the License. 15010662326b9c43c703725f933e95e0897f8a6bddGlenn Kasten */ 16010662326b9c43c703725f933e95e0897f8a6bddGlenn Kasten 172dd4bdd715f586d4d30cf90cc6fc2bbfbce60fe0Glenn Kasten#include <media/nbaio/roundup.h> 18010662326b9c43c703725f933e95e0897f8a6bddGlenn Kasten 19010662326b9c43c703725f933e95e0897f8a6bddGlenn Kastenunsigned roundup(unsigned v) 20010662326b9c43c703725f933e95e0897f8a6bddGlenn Kasten{ 21010662326b9c43c703725f933e95e0897f8a6bddGlenn Kasten // __builtin_clz is undefined for zero input 22010662326b9c43c703725f933e95e0897f8a6bddGlenn Kasten if (v == 0) { 23010662326b9c43c703725f933e95e0897f8a6bddGlenn Kasten v = 1; 24010662326b9c43c703725f933e95e0897f8a6bddGlenn Kasten } 25010662326b9c43c703725f933e95e0897f8a6bddGlenn Kasten int lz = __builtin_clz((int) v); 26010662326b9c43c703725f933e95e0897f8a6bddGlenn Kasten unsigned rounded = ((unsigned) 0x80000000) >> lz; 27010662326b9c43c703725f933e95e0897f8a6bddGlenn Kasten // 0x800000001 and higher are actually rounded _down_ to prevent overflow 28010662326b9c43c703725f933e95e0897f8a6bddGlenn Kasten if (v > rounded && lz > 0) { 29010662326b9c43c703725f933e95e0897f8a6bddGlenn Kasten rounded <<= 1; 30010662326b9c43c703725f933e95e0897f8a6bddGlenn Kasten } 31010662326b9c43c703725f933e95e0897f8a6bddGlenn Kasten return rounded; 32010662326b9c43c703725f933e95e0897f8a6bddGlenn Kasten} 33