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author | Daniel J Walsh <dwalsh@redhat.com> | 2018-07-08 07:55:30 -0400 |
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committer | Atomic Bot <atomic-devel@projectatomic.io> | 2018-07-19 18:43:32 +0000 |
commit | 98703eb204923f06555605c648fc165a55214520 (patch) | |
tree | a407bae8b3489d4f9b0f0d0f228658bbfe95a38e /vendor/github.com/ulikunitz/xz/lzma/bitops.go | |
parent | c020db8cd21cb221cfbe36b264e0ec02999596ed (diff) | |
download | podman-98703eb204923f06555605c648fc165a55214520.tar.gz podman-98703eb204923f06555605c648fc165a55214520.tar.bz2 podman-98703eb204923f06555605c648fc165a55214520.zip |
Vendor in latest code for storage,image, buildah
vendor in containers/storage
vendor in containers/image
vendor in projectatomic/buildah
Signed-off-by: Daniel J Walsh <dwalsh@redhat.com>
Closes: #1114
Approved by: mheon
Diffstat (limited to 'vendor/github.com/ulikunitz/xz/lzma/bitops.go')
-rw-r--r-- | vendor/github.com/ulikunitz/xz/lzma/bitops.go | 45 |
1 files changed, 45 insertions, 0 deletions
diff --git a/vendor/github.com/ulikunitz/xz/lzma/bitops.go b/vendor/github.com/ulikunitz/xz/lzma/bitops.go new file mode 100644 index 000000000..e9bab0199 --- /dev/null +++ b/vendor/github.com/ulikunitz/xz/lzma/bitops.go @@ -0,0 +1,45 @@ +// Copyright 2014-2017 Ulrich Kunitz. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package lzma + +/* Naming conventions follows the CodeReviewComments in the Go Wiki. */ + +// ntz32Const is used by the functions NTZ and NLZ. +const ntz32Const = 0x04d7651f + +// ntz32Table is a helper table for de Bruijn algorithm by Danny Dubé. +// See Henry S. Warren, Jr. "Hacker's Delight" section 5-1 figure 5-26. +var ntz32Table = [32]int8{ + 0, 1, 2, 24, 3, 19, 6, 25, + 22, 4, 20, 10, 16, 7, 12, 26, + 31, 23, 18, 5, 21, 9, 15, 11, + 30, 17, 8, 14, 29, 13, 28, 27, +} + +// ntz32 computes the number of trailing zeros for an unsigned 32-bit integer. +func ntz32(x uint32) int { + if x == 0 { + return 32 + } + x = (x & -x) * ntz32Const + return int(ntz32Table[x>>27]) +} + +// nlz32 computes the number of leading zeros for an unsigned 32-bit integer. +func nlz32(x uint32) int { + // Smear left most bit to the right + x |= x >> 1 + x |= x >> 2 + x |= x >> 4 + x |= x >> 8 + x |= x >> 16 + // Use ntz mechanism to calculate nlz. + x++ + if x == 0 { + return 0 + } + x *= ntz32Const + return 32 - int(ntz32Table[x>>27]) +} |