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forgejo/vendor/github.com/RoaringBitmap/roaring/rle16.go
2018-05-19 20:49:46 +08:00

1747 lines
44 KiB
Go

package roaring
//
// Copyright (c) 2016 by the roaring authors.
// Licensed under the Apache License, Version 2.0.
//
// We derive a few lines of code from the sort.Search
// function in the golang standard library. That function
// is Copyright 2009 The Go Authors, and licensed
// under the following BSD-style license.
/*
Copyright (c) 2009 The Go Authors. All rights reserved.
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are
met:
* Redistributions of source code must retain the above copyright
notice, this list of conditions and the following disclaimer.
* Redistributions in binary form must reproduce the above
copyright notice, this list of conditions and the following disclaimer
in the documentation and/or other materials provided with the
distribution.
* Neither the name of Google Inc. nor the names of its
contributors may be used to endorse or promote products derived from
this software without specific prior written permission.
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
import (
"fmt"
"sort"
"unsafe"
)
//go:generate msgp -unexported
// runContainer16 does run-length encoding of sets of
// uint16 integers.
type runContainer16 struct {
iv []interval16
card int64
// avoid allocation during search
myOpts searchOptions `msg:"-"`
}
// interval16 is the internal to runContainer16
// structure that maintains the individual [start, last]
// closed intervals.
type interval16 struct {
start uint16
length uint16 // length minus 1
}
func newInterval16Range(start, last uint16) interval16 {
if last < start {
panic(fmt.Sprintf("last (%d) cannot be smaller than start (%d)", last, start))
}
return interval16{
start,
last - start,
}
}
// runlen returns the count of integers in the interval.
func (iv interval16) runlen() int64 {
return int64(iv.length) + 1
}
func (iv interval16) last() uint16 {
return iv.start + iv.length
}
// String produces a human viewable string of the contents.
func (iv interval16) String() string {
return fmt.Sprintf("[%d, %d]", iv.start, iv.length)
}
func ivalString16(iv []interval16) string {
var s string
var j int
var p interval16
for j, p = range iv {
s += fmt.Sprintf("%v:[%d, %d], ", j, p.start, p.last())
}
return s
}
// String produces a human viewable string of the contents.
func (rc *runContainer16) String() string {
if len(rc.iv) == 0 {
return "runContainer16{}"
}
is := ivalString16(rc.iv)
return `runContainer16{` + is + `}`
}
// uint16Slice is a sort.Sort convenience method
type uint16Slice []uint16
// Len returns the length of p.
func (p uint16Slice) Len() int { return len(p) }
// Less returns p[i] < p[j]
func (p uint16Slice) Less(i, j int) bool { return p[i] < p[j] }
// Swap swaps elements i and j.
func (p uint16Slice) Swap(i, j int) { p[i], p[j] = p[j], p[i] }
//msgp:ignore addHelper
// addHelper helps build a runContainer16.
type addHelper16 struct {
runstart uint16
runlen uint16
actuallyAdded uint16
m []interval16
rc *runContainer16
}
func (ah *addHelper16) storeIval(runstart, runlen uint16) {
mi := interval16{start: runstart, length: runlen}
ah.m = append(ah.m, mi)
}
func (ah *addHelper16) add(cur, prev uint16, i int) {
if cur == prev+1 {
ah.runlen++
ah.actuallyAdded++
} else {
if cur < prev {
panic(fmt.Sprintf("newRunContainer16FromVals sees "+
"unsorted vals; vals[%v]=cur=%v < prev=%v. Sort your vals"+
" before calling us with alreadySorted == true.", i, cur, prev))
}
if cur == prev {
// ignore duplicates
} else {
ah.actuallyAdded++
ah.storeIval(ah.runstart, ah.runlen)
ah.runstart = cur
ah.runlen = 0
}
}
}
// newRunContainerRange makes a new container made of just the specified closed interval [rangestart,rangelast]
func newRunContainer16Range(rangestart uint16, rangelast uint16) *runContainer16 {
rc := &runContainer16{}
rc.iv = append(rc.iv, newInterval16Range(rangestart, rangelast))
return rc
}
// newRunContainer16FromVals makes a new container from vals.
//
// For efficiency, vals should be sorted in ascending order.
// Ideally vals should not contain duplicates, but we detect and
// ignore them. If vals is already sorted in ascending order, then
// pass alreadySorted = true. Otherwise, for !alreadySorted,
// we will sort vals before creating a runContainer16 of them.
// We sort the original vals, so this will change what the
// caller sees in vals as a side effect.
func newRunContainer16FromVals(alreadySorted bool, vals ...uint16) *runContainer16 {
// keep this in sync with newRunContainer16FromArray below
rc := &runContainer16{}
ah := addHelper16{rc: rc}
if !alreadySorted {
sort.Sort(uint16Slice(vals))
}
n := len(vals)
var cur, prev uint16
switch {
case n == 0:
// nothing more
case n == 1:
ah.m = append(ah.m, newInterval16Range(vals[0], vals[0]))
ah.actuallyAdded++
default:
ah.runstart = vals[0]
ah.actuallyAdded++
for i := 1; i < n; i++ {
prev = vals[i-1]
cur = vals[i]
ah.add(cur, prev, i)
}
ah.storeIval(ah.runstart, ah.runlen)
}
rc.iv = ah.m
rc.card = int64(ah.actuallyAdded)
return rc
}
// newRunContainer16FromBitmapContainer makes a new run container from bc,
// somewhat efficiently. For reference, see the Java
// https://github.com/RoaringBitmap/RoaringBitmap/blob/master/src/main/java/org/roaringbitmap/RunContainer.java#L145-L192
func newRunContainer16FromBitmapContainer(bc *bitmapContainer) *runContainer16 {
rc := &runContainer16{}
nbrRuns := bc.numberOfRuns()
if nbrRuns == 0 {
return rc
}
rc.iv = make([]interval16, nbrRuns)
longCtr := 0 // index of current long in bitmap
curWord := bc.bitmap[0] // its value
runCount := 0
for {
// potentially multiword advance to first 1 bit
for curWord == 0 && longCtr < len(bc.bitmap)-1 {
longCtr++
curWord = bc.bitmap[longCtr]
}
if curWord == 0 {
// wrap up, no more runs
return rc
}
localRunStart := countTrailingZeros(curWord)
runStart := localRunStart + 64*longCtr
// stuff 1s into number's LSBs
curWordWith1s := curWord | (curWord - 1)
// find the next 0, potentially in a later word
runEnd := 0
for curWordWith1s == maxWord && longCtr < len(bc.bitmap)-1 {
longCtr++
curWordWith1s = bc.bitmap[longCtr]
}
if curWordWith1s == maxWord {
// a final unterminated run of 1s
runEnd = wordSizeInBits + longCtr*64
rc.iv[runCount].start = uint16(runStart)
rc.iv[runCount].length = uint16(runEnd) - uint16(runStart) - 1
return rc
}
localRunEnd := countTrailingZeros(^curWordWith1s)
runEnd = localRunEnd + longCtr*64
rc.iv[runCount].start = uint16(runStart)
rc.iv[runCount].length = uint16(runEnd) - 1 - uint16(runStart)
runCount++
// now, zero out everything right of runEnd.
curWord = curWordWith1s & (curWordWith1s + 1)
// We've lathered and rinsed, so repeat...
}
}
//
// newRunContainer16FromArray populates a new
// runContainer16 from the contents of arr.
//
func newRunContainer16FromArray(arr *arrayContainer) *runContainer16 {
// keep this in sync with newRunContainer16FromVals above
rc := &runContainer16{}
ah := addHelper16{rc: rc}
n := arr.getCardinality()
var cur, prev uint16
switch {
case n == 0:
// nothing more
case n == 1:
ah.m = append(ah.m, newInterval16Range(arr.content[0], arr.content[0]))
ah.actuallyAdded++
default:
ah.runstart = arr.content[0]
ah.actuallyAdded++
for i := 1; i < n; i++ {
prev = arr.content[i-1]
cur = arr.content[i]
ah.add(cur, prev, i)
}
ah.storeIval(ah.runstart, ah.runlen)
}
rc.iv = ah.m
rc.card = int64(ah.actuallyAdded)
return rc
}
// set adds the integers in vals to the set. Vals
// must be sorted in increasing order; if not, you should set
// alreadySorted to false, and we will sort them in place for you.
// (Be aware of this side effect -- it will affect the callers
// view of vals).
//
// If you have a small number of additions to an already
// big runContainer16, calling Add() may be faster.
func (rc *runContainer16) set(alreadySorted bool, vals ...uint16) {
rc2 := newRunContainer16FromVals(alreadySorted, vals...)
un := rc.union(rc2)
rc.iv = un.iv
rc.card = 0
}
// canMerge returns true iff the intervals
// a and b either overlap or they are
// contiguous and so can be merged into
// a single interval.
func canMerge16(a, b interval16) bool {
if int64(a.last())+1 < int64(b.start) {
return false
}
return int64(b.last())+1 >= int64(a.start)
}
// haveOverlap differs from canMerge in that
// it tells you if the intersection of a
// and b would contain an element (otherwise
// it would be the empty set, and we return
// false).
func haveOverlap16(a, b interval16) bool {
if int64(a.last())+1 <= int64(b.start) {
return false
}
return int64(b.last())+1 > int64(a.start)
}
// mergeInterval16s joins a and b into a
// new interval, and panics if it cannot.
func mergeInterval16s(a, b interval16) (res interval16) {
if !canMerge16(a, b) {
panic(fmt.Sprintf("cannot merge %#v and %#v", a, b))
}
if b.start < a.start {
res.start = b.start
} else {
res.start = a.start
}
if b.last() > a.last() {
res.length = b.last() - res.start
} else {
res.length = a.last() - res.start
}
return
}
// intersectInterval16s returns the intersection
// of a and b. The isEmpty flag will be true if
// a and b were disjoint.
func intersectInterval16s(a, b interval16) (res interval16, isEmpty bool) {
if !haveOverlap16(a, b) {
isEmpty = true
return
}
if b.start > a.start {
res.start = b.start
} else {
res.start = a.start
}
bEnd := b.last()
aEnd := a.last()
var resEnd uint16
if bEnd < aEnd {
resEnd = bEnd
} else {
resEnd = aEnd
}
res.length = resEnd - res.start
return
}
// union merges two runContainer16s, producing
// a new runContainer16 with the union of rc and b.
func (rc *runContainer16) union(b *runContainer16) *runContainer16 {
// rc is also known as 'a' here, but golint insisted we
// call it rc for consistency with the rest of the methods.
var m []interval16
alim := int64(len(rc.iv))
blim := int64(len(b.iv))
var na int64 // next from a
var nb int64 // next from b
// merged holds the current merge output, which might
// get additional merges before being appended to m.
var merged interval16
var mergedUsed bool // is merged being used at the moment?
var cura interval16 // currently considering this interval16 from a
var curb interval16 // currently considering this interval16 from b
pass := 0
for na < alim && nb < blim {
pass++
cura = rc.iv[na]
curb = b.iv[nb]
if mergedUsed {
mergedUpdated := false
if canMerge16(cura, merged) {
merged = mergeInterval16s(cura, merged)
na = rc.indexOfIntervalAtOrAfter(int64(merged.last())+1, na+1)
mergedUpdated = true
}
if canMerge16(curb, merged) {
merged = mergeInterval16s(curb, merged)
nb = b.indexOfIntervalAtOrAfter(int64(merged.last())+1, nb+1)
mergedUpdated = true
}
if !mergedUpdated {
// we know that merged is disjoint from cura and curb
m = append(m, merged)
mergedUsed = false
}
continue
} else {
// !mergedUsed
if !canMerge16(cura, curb) {
if cura.start < curb.start {
m = append(m, cura)
na++
} else {
m = append(m, curb)
nb++
}
} else {
merged = mergeInterval16s(cura, curb)
mergedUsed = true
na = rc.indexOfIntervalAtOrAfter(int64(merged.last())+1, na+1)
nb = b.indexOfIntervalAtOrAfter(int64(merged.last())+1, nb+1)
}
}
}
var aDone, bDone bool
if na >= alim {
aDone = true
}
if nb >= blim {
bDone = true
}
// finish by merging anything remaining into merged we can:
if mergedUsed {
if !aDone {
aAdds:
for na < alim {
cura = rc.iv[na]
if canMerge16(cura, merged) {
merged = mergeInterval16s(cura, merged)
na = rc.indexOfIntervalAtOrAfter(int64(merged.last())+1, na+1)
} else {
break aAdds
}
}
}
if !bDone {
bAdds:
for nb < blim {
curb = b.iv[nb]
if canMerge16(curb, merged) {
merged = mergeInterval16s(curb, merged)
nb = b.indexOfIntervalAtOrAfter(int64(merged.last())+1, nb+1)
} else {
break bAdds
}
}
}
m = append(m, merged)
}
if na < alim {
m = append(m, rc.iv[na:]...)
}
if nb < blim {
m = append(m, b.iv[nb:]...)
}
res := &runContainer16{iv: m}
return res
}
// unionCardinality returns the cardinality of the merger of two runContainer16s, the union of rc and b.
func (rc *runContainer16) unionCardinality(b *runContainer16) uint64 {
// rc is also known as 'a' here, but golint insisted we
// call it rc for consistency with the rest of the methods.
answer := uint64(0)
alim := int64(len(rc.iv))
blim := int64(len(b.iv))
var na int64 // next from a
var nb int64 // next from b
// merged holds the current merge output, which might
// get additional merges before being appended to m.
var merged interval16
var mergedUsed bool // is merged being used at the moment?
var cura interval16 // currently considering this interval16 from a
var curb interval16 // currently considering this interval16 from b
pass := 0
for na < alim && nb < blim {
pass++
cura = rc.iv[na]
curb = b.iv[nb]
if mergedUsed {
mergedUpdated := false
if canMerge16(cura, merged) {
merged = mergeInterval16s(cura, merged)
na = rc.indexOfIntervalAtOrAfter(int64(merged.last())+1, na+1)
mergedUpdated = true
}
if canMerge16(curb, merged) {
merged = mergeInterval16s(curb, merged)
nb = b.indexOfIntervalAtOrAfter(int64(merged.last())+1, nb+1)
mergedUpdated = true
}
if !mergedUpdated {
// we know that merged is disjoint from cura and curb
//m = append(m, merged)
answer += uint64(merged.last()) - uint64(merged.start) + 1
mergedUsed = false
}
continue
} else {
// !mergedUsed
if !canMerge16(cura, curb) {
if cura.start < curb.start {
answer += uint64(cura.last()) - uint64(cura.start) + 1
//m = append(m, cura)
na++
} else {
answer += uint64(curb.last()) - uint64(curb.start) + 1
//m = append(m, curb)
nb++
}
} else {
merged = mergeInterval16s(cura, curb)
mergedUsed = true
na = rc.indexOfIntervalAtOrAfter(int64(merged.last())+1, na+1)
nb = b.indexOfIntervalAtOrAfter(int64(merged.last())+1, nb+1)
}
}
}
var aDone, bDone bool
if na >= alim {
aDone = true
}
if nb >= blim {
bDone = true
}
// finish by merging anything remaining into merged we can:
if mergedUsed {
if !aDone {
aAdds:
for na < alim {
cura = rc.iv[na]
if canMerge16(cura, merged) {
merged = mergeInterval16s(cura, merged)
na = rc.indexOfIntervalAtOrAfter(int64(merged.last())+1, na+1)
} else {
break aAdds
}
}
}
if !bDone {
bAdds:
for nb < blim {
curb = b.iv[nb]
if canMerge16(curb, merged) {
merged = mergeInterval16s(curb, merged)
nb = b.indexOfIntervalAtOrAfter(int64(merged.last())+1, nb+1)
} else {
break bAdds
}
}
}
//m = append(m, merged)
answer += uint64(merged.last()) - uint64(merged.start) + 1
}
for _, r := range rc.iv[na:] {
answer += uint64(r.last()) - uint64(r.start) + 1
}
for _, r := range b.iv[nb:] {
answer += uint64(r.last()) - uint64(r.start) + 1
}
return answer
}
// indexOfIntervalAtOrAfter is a helper for union.
func (rc *runContainer16) indexOfIntervalAtOrAfter(key int64, startIndex int64) int64 {
rc.myOpts.startIndex = startIndex
rc.myOpts.endxIndex = 0
w, already, _ := rc.search(key, &rc.myOpts)
if already {
return w
}
return w + 1
}
// intersect returns a new runContainer16 holding the
// intersection of rc (also known as 'a') and b.
func (rc *runContainer16) intersect(b *runContainer16) *runContainer16 {
a := rc
numa := int64(len(a.iv))
numb := int64(len(b.iv))
res := &runContainer16{}
if numa == 0 || numb == 0 {
return res
}
if numa == 1 && numb == 1 {
if !haveOverlap16(a.iv[0], b.iv[0]) {
return res
}
}
var output []interval16
var acuri int64
var bcuri int64
astart := int64(a.iv[acuri].start)
bstart := int64(b.iv[bcuri].start)
var intersection interval16
var leftoverstart int64
var isOverlap, isLeftoverA, isLeftoverB bool
var done bool
toploop:
for acuri < numa && bcuri < numb {
isOverlap, isLeftoverA, isLeftoverB, leftoverstart, intersection =
intersectWithLeftover16(astart, int64(a.iv[acuri].last()), bstart, int64(b.iv[bcuri].last()))
if !isOverlap {
switch {
case astart < bstart:
acuri, done = a.findNextIntervalThatIntersectsStartingFrom(acuri+1, bstart)
if done {
break toploop
}
astart = int64(a.iv[acuri].start)
case astart > bstart:
bcuri, done = b.findNextIntervalThatIntersectsStartingFrom(bcuri+1, astart)
if done {
break toploop
}
bstart = int64(b.iv[bcuri].start)
//default:
// panic("impossible that astart == bstart, since !isOverlap")
}
} else {
// isOverlap
output = append(output, intersection)
switch {
case isLeftoverA:
// note that we change astart without advancing acuri,
// since we need to capture any 2ndary intersections with a.iv[acuri]
astart = leftoverstart
bcuri++
if bcuri >= numb {
break toploop
}
bstart = int64(b.iv[bcuri].start)
case isLeftoverB:
// note that we change bstart without advancing bcuri,
// since we need to capture any 2ndary intersections with b.iv[bcuri]
bstart = leftoverstart
acuri++
if acuri >= numa {
break toploop
}
astart = int64(a.iv[acuri].start)
default:
// neither had leftover, both completely consumed
// optionally, assert for sanity:
//if a.iv[acuri].endx != b.iv[bcuri].endx {
// panic("huh? should only be possible that endx agree now!")
//}
// advance to next a interval
acuri++
if acuri >= numa {
break toploop
}
astart = int64(a.iv[acuri].start)
// advance to next b interval
bcuri++
if bcuri >= numb {
break toploop
}
bstart = int64(b.iv[bcuri].start)
}
}
} // end for toploop
if len(output) == 0 {
return res
}
res.iv = output
return res
}
// intersectCardinality returns the cardinality of the
// intersection of rc (also known as 'a') and b.
func (rc *runContainer16) intersectCardinality(b *runContainer16) int64 {
answer := int64(0)
a := rc
numa := int64(len(a.iv))
numb := int64(len(b.iv))
if numa == 0 || numb == 0 {
return 0
}
if numa == 1 && numb == 1 {
if !haveOverlap16(a.iv[0], b.iv[0]) {
return 0
}
}
var acuri int64
var bcuri int64
astart := int64(a.iv[acuri].start)
bstart := int64(b.iv[bcuri].start)
var intersection interval16
var leftoverstart int64
var isOverlap, isLeftoverA, isLeftoverB bool
var done bool
pass := 0
toploop:
for acuri < numa && bcuri < numb {
pass++
isOverlap, isLeftoverA, isLeftoverB, leftoverstart, intersection =
intersectWithLeftover16(astart, int64(a.iv[acuri].last()), bstart, int64(b.iv[bcuri].last()))
if !isOverlap {
switch {
case astart < bstart:
acuri, done = a.findNextIntervalThatIntersectsStartingFrom(acuri+1, bstart)
if done {
break toploop
}
astart = int64(a.iv[acuri].start)
case astart > bstart:
bcuri, done = b.findNextIntervalThatIntersectsStartingFrom(bcuri+1, astart)
if done {
break toploop
}
bstart = int64(b.iv[bcuri].start)
//default:
// panic("impossible that astart == bstart, since !isOverlap")
}
} else {
// isOverlap
answer += int64(intersection.last()) - int64(intersection.start) + 1
switch {
case isLeftoverA:
// note that we change astart without advancing acuri,
// since we need to capture any 2ndary intersections with a.iv[acuri]
astart = leftoverstart
bcuri++
if bcuri >= numb {
break toploop
}
bstart = int64(b.iv[bcuri].start)
case isLeftoverB:
// note that we change bstart without advancing bcuri,
// since we need to capture any 2ndary intersections with b.iv[bcuri]
bstart = leftoverstart
acuri++
if acuri >= numa {
break toploop
}
astart = int64(a.iv[acuri].start)
default:
// neither had leftover, both completely consumed
// optionally, assert for sanity:
//if a.iv[acuri].endx != b.iv[bcuri].endx {
// panic("huh? should only be possible that endx agree now!")
//}
// advance to next a interval
acuri++
if acuri >= numa {
break toploop
}
astart = int64(a.iv[acuri].start)
// advance to next b interval
bcuri++
if bcuri >= numb {
break toploop
}
bstart = int64(b.iv[bcuri].start)
}
}
} // end for toploop
return answer
}
// get returns true iff key is in the container.
func (rc *runContainer16) contains(key uint16) bool {
_, in, _ := rc.search(int64(key), nil)
return in
}
// numIntervals returns the count of intervals in the container.
func (rc *runContainer16) numIntervals() int {
return len(rc.iv)
}
// search returns alreadyPresent to indicate if the
// key is already in one of our interval16s.
//
// If key is alreadyPresent, then whichInterval16 tells
// you where.
//
// If key is not already present, then whichInterval16 is
// set as follows:
//
// a) whichInterval16 == len(rc.iv)-1 if key is beyond our
// last interval16 in rc.iv;
//
// b) whichInterval16 == -1 if key is before our first
// interval16 in rc.iv;
//
// c) whichInterval16 is set to the minimum index of rc.iv
// which comes strictly before the key;
// so rc.iv[whichInterval16].last < key,
// and if whichInterval16+1 exists, then key < rc.iv[whichInterval16+1].start
// (Note that whichInterval16+1 won't exist when
// whichInterval16 is the last interval.)
//
// runContainer16.search always returns whichInterval16 < len(rc.iv).
//
// If not nil, opts can be used to further restrict
// the search space.
//
func (rc *runContainer16) search(key int64, opts *searchOptions) (whichInterval16 int64, alreadyPresent bool, numCompares int) {
n := int64(len(rc.iv))
if n == 0 {
return -1, false, 0
}
startIndex := int64(0)
endxIndex := n
if opts != nil {
startIndex = opts.startIndex
// let endxIndex == 0 mean no effect
if opts.endxIndex > 0 {
endxIndex = opts.endxIndex
}
}
// sort.Search returns the smallest index i
// in [0, n) at which f(i) is true, assuming that on the range [0, n),
// f(i) == true implies f(i+1) == true.
// If there is no such index, Search returns n.
// For correctness, this began as verbatim snippet from
// sort.Search in the Go standard lib.
// We inline our comparison function for speed, and
// annotate with numCompares
// to observe and test that extra bounds are utilized.
i, j := startIndex, endxIndex
for i < j {
h := i + (j-i)/2 // avoid overflow when computing h as the bisector
// i <= h < j
numCompares++
if !(key < int64(rc.iv[h].start)) {
i = h + 1
} else {
j = h
}
}
below := i
// end std lib snippet.
// The above is a simple in-lining and annotation of:
/* below := sort.Search(n,
func(i int) bool {
return key < rc.iv[i].start
})
*/
whichInterval16 = below - 1
if below == n {
// all falses => key is >= start of all interval16s
// ... so does it belong to the last interval16?
if key < int64(rc.iv[n-1].last())+1 {
// yes, it belongs to the last interval16
alreadyPresent = true
return
}
// no, it is beyond the last interval16.
// leave alreadyPreset = false
return
}
// INVAR: key is below rc.iv[below]
if below == 0 {
// key is before the first first interval16.
// leave alreadyPresent = false
return
}
// INVAR: key is >= rc.iv[below-1].start and
// key is < rc.iv[below].start
// is key in below-1 interval16?
if key >= int64(rc.iv[below-1].start) && key < int64(rc.iv[below-1].last())+1 {
// yes, it is. key is in below-1 interval16.
alreadyPresent = true
return
}
// INVAR: key >= rc.iv[below-1].endx && key < rc.iv[below].start
// leave alreadyPresent = false
return
}
// cardinality returns the count of the integers stored in the
// runContainer16.
func (rc *runContainer16) cardinality() int64 {
if len(rc.iv) == 0 {
rc.card = 0
return 0
}
if rc.card > 0 {
return rc.card // already cached
}
// have to compute it
var n int64
for _, p := range rc.iv {
n += p.runlen()
}
rc.card = n // cache it
return n
}
// AsSlice decompresses the contents into a []uint16 slice.
func (rc *runContainer16) AsSlice() []uint16 {
s := make([]uint16, rc.cardinality())
j := 0
for _, p := range rc.iv {
for i := p.start; i <= p.last(); i++ {
s[j] = i
j++
}
}
return s
}
// newRunContainer16 creates an empty run container.
func newRunContainer16() *runContainer16 {
return &runContainer16{}
}
// newRunContainer16CopyIv creates a run container, initializing
// with a copy of the supplied iv slice.
//
func newRunContainer16CopyIv(iv []interval16) *runContainer16 {
rc := &runContainer16{
iv: make([]interval16, len(iv)),
}
copy(rc.iv, iv)
return rc
}
func (rc *runContainer16) Clone() *runContainer16 {
rc2 := newRunContainer16CopyIv(rc.iv)
return rc2
}
// newRunContainer16TakeOwnership returns a new runContainer16
// backed by the provided iv slice, which we will
// assume exclusive control over from now on.
//
func newRunContainer16TakeOwnership(iv []interval16) *runContainer16 {
rc := &runContainer16{
iv: iv,
}
return rc
}
const baseRc16Size = int(unsafe.Sizeof(runContainer16{}))
const perIntervalRc16Size = int(unsafe.Sizeof(interval16{}))
const baseDiskRc16Size = int(unsafe.Sizeof(uint16(0)))
// see also runContainer16SerializedSizeInBytes(numRuns int) int
// getSizeInBytes returns the number of bytes of memory
// required by this runContainer16.
func (rc *runContainer16) getSizeInBytes() int {
return perIntervalRc16Size*len(rc.iv) + baseRc16Size
}
// runContainer16SerializedSizeInBytes returns the number of bytes of disk
// required to hold numRuns in a runContainer16.
func runContainer16SerializedSizeInBytes(numRuns int) int {
return perIntervalRc16Size*numRuns + baseDiskRc16Size
}
// Add adds a single value k to the set.
func (rc *runContainer16) Add(k uint16) (wasNew bool) {
// TODO comment from runContainer16.java:
// it might be better and simpler to do return
// toBitmapOrArrayContainer(getCardinality()).add(k)
// but note that some unit tests use this method to build up test
// runcontainers without calling runOptimize
k64 := int64(k)
index, present, _ := rc.search(k64, nil)
if present {
return // already there
}
wasNew = true
// increment card if it is cached already
if rc.card > 0 {
rc.card++
}
n := int64(len(rc.iv))
if index == -1 {
// we may need to extend the first run
if n > 0 {
if rc.iv[0].start == k+1 {
rc.iv[0].start = k
rc.iv[0].length++
return
}
}
// nope, k stands alone, starting the new first interval16.
rc.iv = append([]interval16{newInterval16Range(k, k)}, rc.iv...)
return
}
// are we off the end? handle both index == n and index == n-1:
if index >= n-1 {
if int64(rc.iv[n-1].last())+1 == k64 {
rc.iv[n-1].length++
return
}
rc.iv = append(rc.iv, newInterval16Range(k, k))
return
}
// INVAR: index and index+1 both exist, and k goes between them.
//
// Now: add k into the middle,
// possibly fusing with index or index+1 interval16
// and possibly resulting in fusing of two interval16s
// that had a one integer gap.
left := index
right := index + 1
// are we fusing left and right by adding k?
if int64(rc.iv[left].last())+1 == k64 && int64(rc.iv[right].start) == k64+1 {
// fuse into left
rc.iv[left].length = rc.iv[right].last() - rc.iv[left].start
// remove redundant right
rc.iv = append(rc.iv[:left+1], rc.iv[right+1:]...)
return
}
// are we an addition to left?
if int64(rc.iv[left].last())+1 == k64 {
// yes
rc.iv[left].length++
return
}
// are we an addition to right?
if int64(rc.iv[right].start) == k64+1 {
// yes
rc.iv[right].start = k
rc.iv[right].length++
return
}
// k makes a standalone new interval16, inserted in the middle
tail := append([]interval16{newInterval16Range(k, k)}, rc.iv[right:]...)
rc.iv = append(rc.iv[:left+1], tail...)
return
}
//msgp:ignore runIterator
// runIterator16 advice: you must call Next() at least once
// before calling Cur(); and you should call HasNext()
// before calling Next() to insure there are contents.
type runIterator16 struct {
rc *runContainer16
curIndex int64
curPosInIndex uint16
curSeq int64
}
// newRunIterator16 returns a new empty run container.
func (rc *runContainer16) newRunIterator16() *runIterator16 {
return &runIterator16{rc: rc, curIndex: -1}
}
// HasNext returns false if calling Next will panic. It
// returns true when there is at least one more value
// available in the iteration sequence.
func (ri *runIterator16) hasNext() bool {
if len(ri.rc.iv) == 0 {
return false
}
if ri.curIndex == -1 {
return true
}
return ri.curSeq+1 < ri.rc.cardinality()
}
// cur returns the current value pointed to by the iterator.
func (ri *runIterator16) cur() uint16 {
return ri.rc.iv[ri.curIndex].start + ri.curPosInIndex
}
// Next returns the next value in the iteration sequence.
func (ri *runIterator16) next() uint16 {
if !ri.hasNext() {
panic("no Next available")
}
if ri.curIndex >= int64(len(ri.rc.iv)) {
panic("runIterator.Next() going beyond what is available")
}
if ri.curIndex == -1 {
// first time is special
ri.curIndex = 0
} else {
ri.curPosInIndex++
if int64(ri.rc.iv[ri.curIndex].start)+int64(ri.curPosInIndex) == int64(ri.rc.iv[ri.curIndex].last())+1 {
ri.curPosInIndex = 0
ri.curIndex++
}
ri.curSeq++
}
return ri.cur()
}
// remove removes the element that the iterator
// is on from the run container. You can use
// Cur if you want to double check what is about
// to be deleted.
func (ri *runIterator16) remove() uint16 {
n := ri.rc.cardinality()
if n == 0 {
panic("runIterator.Remove called on empty runContainer16")
}
cur := ri.cur()
ri.rc.deleteAt(&ri.curIndex, &ri.curPosInIndex, &ri.curSeq)
return cur
}
type manyRunIterator16 struct {
rc *runContainer16
curIndex int64
curPosInIndex uint16
curSeq int64
}
func (rc *runContainer16) newManyRunIterator16() *manyRunIterator16 {
return &manyRunIterator16{rc: rc, curIndex: -1}
}
func (ri *manyRunIterator16) hasNext() bool {
if len(ri.rc.iv) == 0 {
return false
}
if ri.curIndex == -1 {
return true
}
return ri.curSeq+1 < ri.rc.cardinality()
}
// hs are the high bits to include to avoid needing to reiterate over the buffer in NextMany
func (ri *manyRunIterator16) nextMany(hs uint32, buf []uint32) int {
n := 0
if !ri.hasNext() {
return n
}
// start and end are inclusive
for n < len(buf) {
if ri.curIndex == -1 || int(ri.rc.iv[ri.curIndex].length-ri.curPosInIndex) <= 0 {
ri.curPosInIndex = 0
ri.curIndex++
if ri.curIndex == int64(len(ri.rc.iv)) {
break
}
buf[n] = uint32(ri.rc.iv[ri.curIndex].start) | hs
if ri.curIndex != 0 {
ri.curSeq += 1
}
n += 1
// not strictly necessarily due to len(buf)-n min check, but saves some work
continue
}
// add as many as you can from this seq
moreVals := minOfInt(int(ri.rc.iv[ri.curIndex].length-ri.curPosInIndex), len(buf)-n)
base := uint32(ri.rc.iv[ri.curIndex].start+ri.curPosInIndex+1) | hs
// allows BCE
buf2 := buf[n : n+moreVals]
for i := range buf2 {
buf2[i] = base + uint32(i)
}
// update values
ri.curPosInIndex += uint16(moreVals) //moreVals always fits in uint16
ri.curSeq += int64(moreVals)
n += moreVals
}
return n
}
// remove removes key from the container.
func (rc *runContainer16) removeKey(key uint16) (wasPresent bool) {
var index int64
var curSeq int64
index, wasPresent, _ = rc.search(int64(key), nil)
if !wasPresent {
return // already removed, nothing to do.
}
pos := key - rc.iv[index].start
rc.deleteAt(&index, &pos, &curSeq)
return
}
// internal helper functions
func (rc *runContainer16) deleteAt(curIndex *int64, curPosInIndex *uint16, curSeq *int64) {
rc.card--
*curSeq--
ci := *curIndex
pos := *curPosInIndex
// are we first, last, or in the middle of our interval16?
switch {
case pos == 0:
if int64(rc.iv[ci].length) == 0 {
// our interval disappears
rc.iv = append(rc.iv[:ci], rc.iv[ci+1:]...)
// curIndex stays the same, since the delete did
// the advance for us.
*curPosInIndex = 0
} else {
rc.iv[ci].start++ // no longer overflowable
rc.iv[ci].length--
}
case pos == rc.iv[ci].length:
// length
rc.iv[ci].length--
// our interval16 cannot disappear, else we would have been pos == 0, case first above.
*curPosInIndex--
// if we leave *curIndex alone, then Next() will work properly even after the delete.
default:
//middle
// split into two, adding an interval16
new0 := newInterval16Range(rc.iv[ci].start, rc.iv[ci].start+*curPosInIndex-1)
new1start := int64(rc.iv[ci].start+*curPosInIndex) + 1
if new1start > int64(MaxUint16) {
panic("overflow?!?!")
}
new1 := newInterval16Range(uint16(new1start), rc.iv[ci].last())
tail := append([]interval16{new0, new1}, rc.iv[ci+1:]...)
rc.iv = append(rc.iv[:ci], tail...)
// update curIndex and curPosInIndex
*curIndex++
*curPosInIndex = 0
}
}
func have4Overlap16(astart, alast, bstart, blast int64) bool {
if alast+1 <= bstart {
return false
}
return blast+1 > astart
}
func intersectWithLeftover16(astart, alast, bstart, blast int64) (isOverlap, isLeftoverA, isLeftoverB bool, leftoverstart int64, intersection interval16) {
if !have4Overlap16(astart, alast, bstart, blast) {
return
}
isOverlap = true
// do the intersection:
if bstart > astart {
intersection.start = uint16(bstart)
} else {
intersection.start = uint16(astart)
}
switch {
case blast < alast:
isLeftoverA = true
leftoverstart = blast + 1
intersection.length = uint16(blast) - intersection.start
case alast < blast:
isLeftoverB = true
leftoverstart = alast + 1
intersection.length = uint16(alast) - intersection.start
default:
// alast == blast
intersection.length = uint16(alast) - intersection.start
}
return
}
func (rc *runContainer16) findNextIntervalThatIntersectsStartingFrom(startIndex int64, key int64) (index int64, done bool) {
rc.myOpts.startIndex = startIndex
rc.myOpts.endxIndex = 0
w, _, _ := rc.search(key, &rc.myOpts)
// rc.search always returns w < len(rc.iv)
if w < startIndex {
// not found and comes before lower bound startIndex,
// so just use the lower bound.
if startIndex == int64(len(rc.iv)) {
// also this bump up means that we are done
return startIndex, true
}
return startIndex, false
}
return w, false
}
func sliceToString16(m []interval16) string {
s := ""
for i := range m {
s += fmt.Sprintf("%v: %s, ", i, m[i])
}
return s
}
// selectInt16 returns the j-th value in the container.
// We panic of j is out of bounds.
func (rc *runContainer16) selectInt16(j uint16) int {
n := rc.cardinality()
if int64(j) > n {
panic(fmt.Sprintf("Cannot select %v since Cardinality is %v", j, n))
}
var offset int64
for k := range rc.iv {
nextOffset := offset + rc.iv[k].runlen() + 1
if nextOffset > int64(j) {
return int(int64(rc.iv[k].start) + (int64(j) - offset))
}
offset = nextOffset
}
panic(fmt.Sprintf("Cannot select %v since Cardinality is %v", j, n))
}
// helper for invert
func (rc *runContainer16) invertlastInterval(origin uint16, lastIdx int) []interval16 {
cur := rc.iv[lastIdx]
if cur.last() == MaxUint16 {
if cur.start == origin {
return nil // empty container
}
return []interval16{newInterval16Range(origin, cur.start-1)}
}
if cur.start == origin {
return []interval16{newInterval16Range(cur.last()+1, MaxUint16)}
}
// invert splits
return []interval16{
newInterval16Range(origin, cur.start-1),
newInterval16Range(cur.last()+1, MaxUint16),
}
}
// invert returns a new container (not inplace), that is
// the inversion of rc. For each bit b in rc, the
// returned value has !b
func (rc *runContainer16) invert() *runContainer16 {
ni := len(rc.iv)
var m []interval16
switch ni {
case 0:
return &runContainer16{iv: []interval16{newInterval16Range(0, MaxUint16)}}
case 1:
return &runContainer16{iv: rc.invertlastInterval(0, 0)}
}
var invstart int64
ult := ni - 1
for i, cur := range rc.iv {
if i == ult {
// invertlastInteval will add both intervals (b) and (c) in
// diagram below.
m = append(m, rc.invertlastInterval(uint16(invstart), i)...)
break
}
// INVAR: i and cur are not the last interval, there is a next at i+1
//
// ........[cur.start, cur.last] ...... [next.start, next.last]....
// ^ ^ ^
// (a) (b) (c)
//
// Now: we add interval (a); but if (a) is empty, for cur.start==0, we skip it.
if cur.start > 0 {
m = append(m, newInterval16Range(uint16(invstart), cur.start-1))
}
invstart = int64(cur.last() + 1)
}
return &runContainer16{iv: m}
}
func (iv interval16) equal(b interval16) bool {
return iv.start == b.start && iv.length == b.length
}
func (iv interval16) isSuperSetOf(b interval16) bool {
return iv.start <= b.start && b.last() <= iv.last()
}
func (iv interval16) subtractInterval(del interval16) (left []interval16, delcount int64) {
isect, isEmpty := intersectInterval16s(iv, del)
if isEmpty {
return nil, 0
}
if del.isSuperSetOf(iv) {
return nil, iv.runlen()
}
switch {
case isect.start > iv.start && isect.last() < iv.last():
new0 := newInterval16Range(iv.start, isect.start-1)
new1 := newInterval16Range(isect.last()+1, iv.last())
return []interval16{new0, new1}, isect.runlen()
case isect.start == iv.start:
return []interval16{newInterval16Range(isect.last()+1, iv.last())}, isect.runlen()
default:
return []interval16{newInterval16Range(iv.start, isect.start-1)}, isect.runlen()
}
}
func (rc *runContainer16) isubtract(del interval16) {
origiv := make([]interval16, len(rc.iv))
copy(origiv, rc.iv)
n := int64(len(rc.iv))
if n == 0 {
return // already done.
}
_, isEmpty := intersectInterval16s(newInterval16Range(rc.iv[0].start, rc.iv[n-1].last()), del)
if isEmpty {
return // done
}
// INVAR there is some intersection between rc and del
istart, startAlready, _ := rc.search(int64(del.start), nil)
ilast, lastAlready, _ := rc.search(int64(del.last()), nil)
rc.card = -1
if istart == -1 {
if ilast == n-1 && !lastAlready {
rc.iv = nil
return
}
}
// some intervals will remain
switch {
case startAlready && lastAlready:
res0, _ := rc.iv[istart].subtractInterval(del)
// would overwrite values in iv b/c res0 can have len 2. so
// write to origiv instead.
lost := 1 + ilast - istart
changeSize := int64(len(res0)) - lost
newSize := int64(len(rc.iv)) + changeSize
// rc.iv = append(pre, caboose...)
// return
if ilast != istart {
res1, _ := rc.iv[ilast].subtractInterval(del)
res0 = append(res0, res1...)
changeSize = int64(len(res0)) - lost
newSize = int64(len(rc.iv)) + changeSize
}
switch {
case changeSize < 0:
// shrink
copy(rc.iv[istart+int64(len(res0)):], rc.iv[ilast+1:])
copy(rc.iv[istart:istart+int64(len(res0))], res0)
rc.iv = rc.iv[:newSize]
return
case changeSize == 0:
// stay the same
copy(rc.iv[istart:istart+int64(len(res0))], res0)
return
default:
// changeSize > 0 is only possible when ilast == istart.
// Hence we now know: changeSize == 1 and len(res0) == 2
rc.iv = append(rc.iv, interval16{})
// len(rc.iv) is correct now, no need to rc.iv = rc.iv[:newSize]
// copy the tail into place
copy(rc.iv[ilast+2:], rc.iv[ilast+1:])
// copy the new item(s) into place
copy(rc.iv[istart:istart+2], res0)
return
}
case !startAlready && !lastAlready:
// we get to discard whole intervals
// from the search() definition:
// if del.start is not present, then istart is
// set as follows:
//
// a) istart == n-1 if del.start is beyond our
// last interval16 in rc.iv;
//
// b) istart == -1 if del.start is before our first
// interval16 in rc.iv;
//
// c) istart is set to the minimum index of rc.iv
// which comes strictly before the del.start;
// so del.start > rc.iv[istart].last,
// and if istart+1 exists, then del.start < rc.iv[istart+1].startx
// if del.last is not present, then ilast is
// set as follows:
//
// a) ilast == n-1 if del.last is beyond our
// last interval16 in rc.iv;
//
// b) ilast == -1 if del.last is before our first
// interval16 in rc.iv;
//
// c) ilast is set to the minimum index of rc.iv
// which comes strictly before the del.last;
// so del.last > rc.iv[ilast].last,
// and if ilast+1 exists, then del.last < rc.iv[ilast+1].start
// INVAR: istart >= 0
pre := rc.iv[:istart+1]
if ilast == n-1 {
rc.iv = pre
return
}
// INVAR: ilast < n-1
lost := ilast - istart
changeSize := -lost
newSize := int64(len(rc.iv)) + changeSize
if changeSize != 0 {
copy(rc.iv[ilast+1+changeSize:], rc.iv[ilast+1:])
}
rc.iv = rc.iv[:newSize]
return
case startAlready && !lastAlready:
// we can only shrink or stay the same size
// i.e. we either eliminate the whole interval,
// or just cut off the right side.
res0, _ := rc.iv[istart].subtractInterval(del)
if len(res0) > 0 {
// len(res) must be 1
rc.iv[istart] = res0[0]
}
lost := 1 + (ilast - istart)
changeSize := int64(len(res0)) - lost
newSize := int64(len(rc.iv)) + changeSize
if changeSize != 0 {
copy(rc.iv[ilast+1+changeSize:], rc.iv[ilast+1:])
}
rc.iv = rc.iv[:newSize]
return
case !startAlready && lastAlready:
// we can only shrink or stay the same size
res1, _ := rc.iv[ilast].subtractInterval(del)
lost := ilast - istart
changeSize := int64(len(res1)) - lost
newSize := int64(len(rc.iv)) + changeSize
if changeSize != 0 {
// move the tail first to make room for res1
copy(rc.iv[ilast+1+changeSize:], rc.iv[ilast+1:])
}
copy(rc.iv[istart+1:], res1)
rc.iv = rc.iv[:newSize]
return
}
}
// compute rc minus b, and return the result as a new value (not inplace).
// port of run_container_andnot from CRoaring...
// https://github.com/RoaringBitmap/CRoaring/blob/master/src/containers/run.c#L435-L496
func (rc *runContainer16) AndNotRunContainer16(b *runContainer16) *runContainer16 {
if len(b.iv) == 0 || len(rc.iv) == 0 {
return rc
}
dst := newRunContainer16()
apos := 0
bpos := 0
a := rc
astart := a.iv[apos].start
alast := a.iv[apos].last()
bstart := b.iv[bpos].start
blast := b.iv[bpos].last()
alen := len(a.iv)
blen := len(b.iv)
for apos < alen && bpos < blen {
switch {
case alast < bstart:
// output the first run
dst.iv = append(dst.iv, newInterval16Range(astart, alast))
apos++
if apos < alen {
astart = a.iv[apos].start
alast = a.iv[apos].last()
}
case blast < astart:
// exit the second run
bpos++
if bpos < blen {
bstart = b.iv[bpos].start
blast = b.iv[bpos].last()
}
default:
// a: [ ]
// b: [ ]
// alast >= bstart
// blast >= astart
if astart < bstart {
dst.iv = append(dst.iv, newInterval16Range(astart, bstart-1))
}
if alast > blast {
astart = blast + 1
} else {
apos++
if apos < alen {
astart = a.iv[apos].start
alast = a.iv[apos].last()
}
}
}
}
if apos < alen {
dst.iv = append(dst.iv, newInterval16Range(astart, alast))
apos++
if apos < alen {
dst.iv = append(dst.iv, a.iv[apos:]...)
}
}
return dst
}
func (rc *runContainer16) numberOfRuns() (nr int) {
return len(rc.iv)
}
func (rc *runContainer16) containerType() contype {
return run16Contype
}
func (rc *runContainer16) equals16(srb *runContainer16) bool {
//p("both rc16")
// Check if the containers are the same object.
if rc == srb {
//p("same object")
return true
}
if len(srb.iv) != len(rc.iv) {
//p("iv len differ")
return false
}
for i, v := range rc.iv {
if v != srb.iv[i] {
//p("differ at iv i=%v, srb.iv[i]=%v, rc.iv[i]=%v", i, srb.iv[i], rc.iv[i])
return false
}
}
//p("all intervals same, returning true")
return true
}