From bb7443f6d6f09411ea10f06e6cb0d416bd1ccebd Mon Sep 17 00:00:00 2001 From: Radim Krčmář Date: Tue, 17 Feb 2015 17:30:52 +0100 Subject: qxl: refactor rounding up to a nearest power of 2 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit We already have pow2floor, mirror it and use instead of a function with similar results (same in used domain), to clarify our intent. Signed-off-by: Radim Krčmář Signed-off-by: Gerd Hoffmann --- util/cutils.c | 14 ++++++++++++++ 1 file changed, 14 insertions(+) (limited to 'util') diff --git a/util/cutils.c b/util/cutils.c index dbe7412bd8..c2250d1ba5 100644 --- a/util/cutils.c +++ b/util/cutils.c @@ -483,6 +483,20 @@ int64_t pow2floor(int64_t value) return value; } +/* round up to the nearest power of 2 (0 if overflow) */ +uint64_t pow2ceil(uint64_t value) +{ + uint8_t nlz = clz64(value); + + if (is_power_of_2(value)) { + return value; + } + if (!nlz) { + return 0; + } + return 1ULL << (64 - nlz); +} + /* * Implementation of ULEB128 (http://en.wikipedia.org/wiki/LEB128) * Input is limited to 14-bit numbers -- cgit v1.2.3