open-vault/vendor/github.com/ulikunitz/xz/lzma/bitops.go
Calvin Leung Huang d2dbb8c963
Vault Debug (#7375)
* cli: initial work on debug; server-status target

* debug: add metrics capture target (#7376)

* check against DR secondary

* debug: add compression

* refactor check into preflight func

* debug: set short test time on tests, fix exit code bug

* debug: use temp dir for output on tests

* debug: use mholt/archiver for compression

* first pass on adding pprof

* use logger for output

* refactor polling target capture logic

* debug: poll and collect replication status

* debug: poll and collect host-info; rename output files and collection refactor

* fix comments

* add archive test; fix bugs found

* rename flag name to singular target

* add target output test; scaffold other tests cases

* debug/test: add pprof and index file tests

* debug/test: add min timing check tests

* debug: fix index gen race and collection goroutine race

* debug: extend archive tests, handle race between program exit and polling goroutines

* update docstring

* debug: correctly add to pollingWg

* debug: add config target support

* debug: don't wait on interrupt shutdown; add file exists unit tests

* move pprof bits into its goroutine

* debug: skip empty metrics and some pprof file creation if permission denied, add matching unit test

* address comments and feedback

* Vault debug using run.Group (#7658)

* debug: switch to use oklog/run.Group

* debug: use context to cancel requests and interrupt rungroups.

* debug: trigger the first interval properly

* debug: metrics collection should use metrics interval

* debug: add missing continue on metrics error

* debug: remove the use of buffered chan to trigger first interval

* debug: don't shadow BaseCommand's client, properly block on interval capture failures

* debug: actually use c.cachedClient everywhere

* go mod vendor

* debug: run all pprof in goroutines; bump pprof timings in tests to reduce flakiness

* debug: update help text
2019-10-15 15:39:19 -07:00

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1.1 KiB
Go

// 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])
}