featurebase/roaring/roaring.go
Matthew Jaffee 6d4c1d9db1
Sup 294 pre sort command (#2209)
* first cut at pre-sort command that works on ndjson

* finish pre_sort command for CSV and JSON and add test

* try fixing golangci-lint

* remove some dumb lint checks

* more linter disabling

* take .golangci.yml from previous repo

* go fmt (facepalm)

* remove ioutil to fix lint
2023-01-23 12:26:38 -06:00

7712 lines
194 KiB
Go

// Copyright 2022 Molecula Corp. (DBA FeatureBase).
// SPDX-License-Identifier: Apache-2.0
// Package roaring implements roaring bitmaps with support for incremental changes.
package roaring
import (
"bytes"
"encoding/binary"
"fmt"
"hash/fnv"
"io"
"math/bits"
"sort"
"unsafe"
"github.com/pkg/errors"
)
const (
// MagicNumber is an identifier, in bytes 0-1 of the file.
MagicNumber = uint32(12348)
// storageVersion indicates the storage version, in byte 2.
storageVersion = uint32(0)
// NOTE: byte 3 stores user-defined flags.
// cookie is the first 3 bytes in a roaring bitmap file,
// formed by joining MagicNumber and storageVersion
cookie = MagicNumber + storageVersion<<16
// headerBaseSize is the size in bytes of the cookie, flags, and key count
// at the beginning of a file.
headerBaseSize = 3 + 1 + 4
// runCountHeaderSize is the size in bytes of the run count stored
// at the beginning of every serialized run container.
runCountHeaderSize = 2
// interval16Size is the size of a single run in a container.runs.
interval16Size = 4
// bitmapN is the number of values in a container.bitmap.
bitmapN = (1 << 16) / 64
MaxContainerVal = 0xffff
// maxContainerKey is the key representing the last container in a full row.
// It is the full bitmap space (2^64) divided by container width (2^16).
maxContainerKey = (1 << 48) - 1
)
const (
ContainerNil byte = iota // no container
ContainerArray // slice of bit position values
ContainerBitmap // slice of 1024 uint64s
ContainerRun // container of run-encoded bits
)
// map used for a more descriptive print
var containerTypeNames = map[byte]string{
ContainerArray: "array",
ContainerBitmap: "bitmap",
ContainerRun: "run",
}
var fullContainer = NewContainerRun([]Interval16{{Start: 0, Last: MaxContainerVal}}).Freeze()
// AdvisoryError is used for the special case where we probably want to *report*
// an error reading a file, but don't want to actually count the file as not
// being read. For instance, a partial ops-log entry is *probably* harmless;
// we probably crashed while writing (?) and as such didn't report the write
// as successful. We hope.
type AdvisoryError interface {
error
AdvisoryOnly()
}
type advisoryError struct {
e error
}
func (a advisoryError) Error() string {
return a.e.Error()
}
// This marks the error as safe to ignore.
func (a advisoryError) AdvisoryOnly() {
}
type FileShouldBeTruncatedError interface {
AdvisoryError
SuggestedLength() int64
}
type fileShouldBeTruncatedError struct {
advisoryError
offset int64
}
func (f *fileShouldBeTruncatedError) SuggestedLength() int64 {
return f.offset
}
func newFileShouldBeTruncatedError(err error, offset int64) *fileShouldBeTruncatedError {
return &fileShouldBeTruncatedError{advisoryError: advisoryError{e: err}, offset: offset}
}
type Containers interface {
// Get returns nil if the key does not exist.
Get(key uint64) *Container
// Put adds the container at key.
Put(key uint64, c *Container)
// Remove takes the container at key out.
Remove(key uint64)
// GetOrCreate returns the container at key, creating a new empty container if necessary.
GetOrCreate(key uint64) *Container
// Clone does a deep copy of Containers, including cloning all containers contained.
Clone() Containers
// Freeze creates a shallow copy of Containers, freezing all the containers
// contained. The new copy is a distinct Containers, but the individual containers
// are shared (but marked as frozen).
Freeze() Containers
// Last returns the highest key and associated container.
Last() (key uint64, c *Container)
// Size returns the number of containers stored.
Size() int
// Update calls fn (existing-container, existed), and expects
// (new-container, write). If write is true, the container is used to
// replace the given container.
Update(key uint64, fn func(*Container, bool) (*Container, bool))
// UpdateEvery calls fn (existing-container, existed), and expects
// (new-container, write). If write is true, the container is used to
// replace the given container.
UpdateEvery(fn func(uint64, *Container, bool) (*Container, bool))
// Iterator returns a ContainterIterator which after a call to Next(), a call to Value() will
// return the first container at or after key. found will be true if a
// container is found at key.
Iterator(key uint64) (citer ContainerIterator, found bool)
Count() uint64
// Reset clears the containers collection to allow for recycling during snapshot
Reset()
// ResetN clears the collection but hints at a needed size.
ResetN(int)
// Repair will repair the cardinality of any containers whose cardinality were corrupted
// due to optimized operations.
Repair()
}
type ContainerIterator interface {
Next() bool
Value() (uint64, *Container)
Close()
}
type nopContainerIterator struct{}
func (n nopContainerIterator) Next() bool { return false }
func (n nopContainerIterator) Value() (uint64, *Container) { return 0, nil }
func (n nopContainerIterator) Close() {}
type unionContainerIterator struct {
iters []ContainerIterator
curs []containerWithKey
cur FilterKey
}
// NewUnionContainerIterator unions multiple container iterators to one.
func NewUnionContainerIterator(iters ...ContainerIterator) ContainerIterator {
return &unionContainerIterator{
iters: iters,
curs: make([]containerWithKey, len(iters)),
cur: 0,
}
}
func (u *unionContainerIterator) Next() bool {
if u.cur == KEY_DONE {
return false
}
// Next all iters that are at cur and save lowest
lowest := uint64(KEY_DONE)
for i, iter := range u.iters {
if u.curs[i].key == u.cur {
if iter.Next() {
key, c := iter.Value()
u.curs[i].key, u.curs[i].Container = FilterKey(key), c
if key < lowest {
lowest = key
}
} else {
u.curs[i].key = KEY_DONE
u.curs[i].Container = nil
}
}
}
u.cur = FilterKey(lowest)
return u.cur != KEY_DONE
}
func (u *unionContainerIterator) Value() (uint64, *Container) {
if u.cur == KEY_DONE {
return uint64(KEY_DONE), nil
}
var ret *Container
for _, cur := range u.curs {
if cur.key == u.cur {
ret = ret.UnionInPlace(cur.Container)
}
}
ret.Repair()
return uint64(u.cur), ret
}
func (u *unionContainerIterator) Close() {}
// Bitmap represents a roaring bitmap.
type Bitmap struct {
Containers Containers
// User-defined flags.
Flags byte
// should we try to keep things mapped?
preferMapping bool
// Number of bit change operations written to the writer. Some operations
// contain multiple values, so "ops" represents the number of distinct
// operations, while "opN" represents expected bit changes.
ops int
opN int
// Writer where operations are appended to.
OpWriter io.Writer
}
// NewBitmap returns a Bitmap with an initial set of values.
func NewBitmap(a ...uint64) *Bitmap {
b := &Bitmap{
Containers: newSliceContainers(),
}
// We have no way to report this. We aren't in a server context
// so we haven't got a logger, nothing is checking for nil returns
// from this.
// Because we just created Bitmap, its OpWriter is nil, so there
// is no code path which would cause AddN() to return an error.
// Therefore, it's safe to swallow this error.
_, _ = b.AddN(a...)
return b
}
// NewBitMatrix is a convenience function which returns a new bitmap
// which is the concatenation of all the rows, with each row shifted
// by a shardwdith. For example, all values in the second row will
// have shardWidth added to them before being added to the bitmap.
// Modifies rows in place.
func NewBitMatrix(shardWidth uint64, rows ...[]uint64) *Bitmap {
bm := NewBitmap()
for rowNum, row := range rows {
for i, col := range row {
row[i] = uint64(rowNum)*shardWidth + col
}
bm.AddN(row...)
}
return bm
}
// NewSliceBitmap makes a new bitmap, explicitly selecting the slice containers
// type, which performs better in cases where we expect a contiguous block of
// containers added in ascending order, such as when extracting a range from
// another bitmap.
func NewSliceBitmap(a ...uint64) *Bitmap {
b := &Bitmap{
Containers: newSliceContainers(),
}
// We have no way to report this. We aren't in a server context
// so we haven't got a logger, nothing is checking for nil returns
// from this.
// Because we just created Bitmap, its OpWriter is nil, so there
// is no code path which would cause AddN() to return an error.
// Therefore, it's safe to swallow this error.
_, _ = b.AddN(a...)
return b
}
// NewFileBitmap returns a Bitmap with an initial set of values, used for file storage.
var NewFileBitmap = NewBTreeBitmap
// Clone returns a heap allocated copy of the bitmap.
// Note: The OpWriter IS NOT copied to the new bitmap.
func (b *Bitmap) Clone() *Bitmap {
if b == nil {
return nil
}
// Create a copy of the bitmap structure.
other := &Bitmap{
Containers: b.Containers.Clone(),
}
return other
}
// Freeze returns a shallow copy of the bitmap. The new bitmap
// is a distinct bitmap, with a new Containers object, but the
// actual containers it holds are the same as the parent's
// containers, but have been frozen.
func (b *Bitmap) Freeze() *Bitmap {
if b == nil {
return nil
}
// Create a copy of the bitmap structure.
other := &Bitmap{
Containers: b.Containers.Freeze(),
}
return other
}
// Add adds values to the bitmap. TODO(2.0) deprecate - use the more general
// AddN (though be aware that it modifies 'a' in place).
func (b *Bitmap) Add(a ...uint64) (changed bool, err error) {
changed = false
for _, v := range a {
// Create an add operation.
op := &op{typ: opTypeAdd, value: v}
// Write operation to op log.
if err := b.writeOp(op); err != nil {
return false, err
}
// Apply to the in-memory bitmap.
if b.DirectAdd(v) {
changed = true
}
}
return changed, nil
}
// AddN adds values to the bitmap, appending them all to the op log in a batched
// write. It returns the number of changed bits.
// The input slice may be reordered, and the set of changed bits will end up in a[:changed].
func (b *Bitmap) AddN(a ...uint64) (changed int, err error) {
if len(a) == 0 {
return 0, nil
}
changed = b.DirectAddN(a...) // modifies a in-place
if b.OpWriter != nil && changed > 0 {
op := &op{
typ: opTypeAddBatch,
values: a[:changed],
}
if err := b.writeOp(op); err != nil {
b.DirectRemoveN(op.values...) // reset data since we're returning an error
return 0, errors.Wrap(err, "writing to op log")
}
}
return changed, nil
}
// DirectAddN sets multiple bits in the bitmap, returning how many changed. It
// modifies the slice 'a' in place such that once it's complete a[:changed] will
// be list of changed bits. It is more efficient than repeated calls to
// DirectAdd for semi-dense sorted data because it reuses the container from the
// previous value if the new value has the same highbits instead of looking it
// up each time. TODO: if Containers implementations cached the last few
// Container objects returned from calls like Get and GetOrCreate, this
// optimization would be less useful.
func (b *Bitmap) DirectAddN(a ...uint64) (changed int) {
return b.directOpN((*Container).add, a...)
}
// DirectRemoveN behaves analgously to DirectAddN.
func (b *Bitmap) DirectRemoveN(a ...uint64) (changed int) {
return b.directOpN((*Container).remove, a...)
}
// directOpN contains the logic for DirectAddN and DirectRemoveN. Theoretically,
// it could be used by anything that wanted to apply a boolean-returning
// container level operation across a list of values and return the number of
// trues while modifying the list of values in place to contain the
// true-returning values in order.
func (b *Bitmap) directOpN(op func(c *Container, v uint16) (*Container, bool), a ...uint64) (changed int) {
hb := uint64(0xFFFFFFFFFFFFFFFF) // impossible sentinel value
var cont *Container
for _, v := range a {
if newhb := highbits(v); newhb != hb {
hb = newhb
cont = b.Containers.GetOrCreate(hb)
}
newC, change := op(cont, lowbits(v))
if change {
a[changed] = v
changed++
}
if newC != cont {
b.Containers.Put(hb, newC)
cont = newC
}
}
return changed
}
// DirectAdd adds a value to the bitmap by bypassing the op log. TODO(2.0)
// deprecate in favor of DirectAddN.
func (b *Bitmap) DirectAdd(v uint64) bool {
cont := b.Containers.GetOrCreate(highbits(v))
newC, changed := cont.add(lowbits(v))
if newC != cont {
// avoid returning invalid container, and avoid a slow optimize call.
switch newC.typeID {
case ContainerArray:
if len(newC.array()) > ArrayMaxSize {
newC = newC.arrayToBitmap()
}
case ContainerRun:
if len(newC.runs()) > runMaxSize {
newC = newC.runToBitmap()
}
}
b.Containers.Put(highbits(v), newC)
}
return changed
}
// Contains returns true if v is in the bitmap.
func (b *Bitmap) Contains(v uint64) bool {
if b == nil {
return false
}
c := b.Containers.Get(highbits(v))
if c == nil {
return false
}
return c.Contains(lowbits(v))
}
// Remove removes values from the bitmap (writing to the op log if available).
// TODO(2.0) deprecate - use the more general RemoveN (though be aware that it
// modifies 'a' in place).
func (b *Bitmap) Remove(a ...uint64) (changed bool, err error) {
changed = false
for _, v := range a {
// Create an add operation.
op := &op{typ: opTypeRemove, value: v}
// Write operation to op log.
if err := b.writeOp(op); err != nil {
return false, err
}
// Apply operation to the bitmap.
if op.apply(b) {
changed = true
}
}
return changed, nil
}
// RemoveN behaves analagously to AddN.
func (b *Bitmap) RemoveN(a ...uint64) (changed int, err error) {
if len(a) == 0 {
return 0, nil
}
changed = b.DirectRemoveN(a...) // modifies a in-place
if b.OpWriter != nil && changed > 0 {
op := &op{
typ: opTypeRemoveBatch,
values: a[:changed],
}
if err := b.writeOp(op); err != nil {
b.DirectAddN(op.values...) // reset data since we're returning an error
return 0, errors.Wrap(err, "writing to op log")
}
}
return changed, nil
}
func (b *Bitmap) remove(v uint64) bool {
c := b.Containers.Get(highbits(v))
newC, changed := c.remove(lowbits(v))
if newC != c {
if newC != nil {
b.Containers.Put(highbits(v), newC)
} else {
b.Containers.Remove(highbits(v))
}
}
return changed
}
// Min returns the lowest value in the bitmap.
// Second return value is true if containers exist in the bitmap.
func (b *Bitmap) Min() (uint64, bool) {
v, eof := b.Iterator().Next()
return v, !eof
}
// MinAt returns the lowest value in the bitmap at least equal to its argument.
// Second return value is true if containers exist in the bitmap.
func (b *Bitmap) MinAt(start uint64) (uint64, bool) {
v, eof := b.IteratorAt(start).Next()
return v, !eof
}
// Max returns the highest value in the bitmap.
// Returns zero if the bitmap is empty.
func (b *Bitmap) Max() uint64 {
if b.Containers.Size() == 0 {
return 0
}
hb, c := b.Containers.Last()
lb := c.max()
return hb<<16 | uint64(lb)
}
// Count returns the number of bits set in the bitmap.
func (b *Bitmap) Count() (n uint64) {
return b.Containers.Count()
}
// Any checks whether there are any set bits within the bitmap.
func (b *Bitmap) Any() bool {
iter, _ := b.Containers.Iterator(0)
// TODO (jaffee) I'm not sure if it's possible/legal to have an empty
// container, so this loop may be totally unnecessary. In theory, any empty
// container should be removed from the bitmap though.
for iter.Next() {
_, c := iter.Value()
if c.N() > 0 {
return true
}
}
return false
}
// Size returns the number of bytes required for the bitmap.
func (b *Bitmap) Size() int {
numbytes := 0
citer, _ := b.Containers.Iterator(0)
for citer.Next() {
_, c := citer.Value()
numbytes += c.size()
}
return numbytes
}
// CountRange returns the number of bits set between [start, end).
func (b *Bitmap) CountRange(start, end uint64) (n uint64) {
if roaringSentinel {
if start > end {
panic(fmt.Sprintf("counting in range but %v > %v", start, end))
}
}
if b.Containers.Size() == 0 {
return
}
skey := highbits(start)
ekey := highbits(end)
citer, found := b.Containers.Iterator(highbits(start))
// If range is entirely in one container then just count that range.
if found && skey == ekey {
citer.Next()
_, c := citer.Value()
return uint64(c.countRange(int32(lowbits(start)), int32(lowbits(end))))
}
for citer.Next() {
k, c := citer.Value()
if k < skey {
// TODO remove once we've validated this stuff works
panic("should be impossible for k to be less than skey")
}
// k > ekey handles the case when start > end and where start and end
// are in different containers. Same container case is already handled above.
if k > ekey {
break
}
if k == skey {
n += uint64(c.countRange(int32(lowbits(start)), MaxContainerVal+1))
continue
}
if k < ekey {
n += uint64(c.N())
continue
}
if k == ekey {
n += uint64(c.countRange(0, int32(lowbits(end))))
break
}
}
return n
}
// Slice returns a slice of all integers in the bitmap.
func (b *Bitmap) Slice() []uint64 {
var a []uint64
itr := b.Iterator()
itr.Seek(0)
for v, eof := itr.Next(); !eof; v, eof = itr.Next() {
a = append(a, v)
}
return a
}
// SliceRange returns a slice of integers between [start, end).
func (b *Bitmap) SliceRange(start, end uint64) []uint64 {
if roaringSentinel {
if start > end {
panic(fmt.Sprintf("getting slice in range but %v > %v", start, end))
}
}
var a []uint64
itr := b.Iterator()
itr.Seek(start)
for v, eof := itr.Next(); !eof && v < end; v, eof = itr.Next() {
a = append(a, v)
}
return a
}
// ForEach executes fn for each value in the bitmap.
func (b *Bitmap) ForEach(fn func(uint64) error) error {
itr := b.Iterator()
itr.Seek(0)
for v, eof := itr.Next(); !eof; v, eof = itr.Next() {
if err := fn(v); err != nil {
return err
}
}
return nil
}
// ForEachRange executes fn for each value in the bitmap between [start, end).
func (b *Bitmap) ForEachRange(start, end uint64, fn func(uint64) error) error {
itr := b.Iterator()
itr.Seek(start)
for v, eof := itr.Next(); !eof && v < end; v, eof = itr.Next() {
if err := fn(v); err != nil {
return err
}
}
return nil
}
// OffsetRange returns a new bitmap with a containers offset by start.
// The containers themselves are shared, so they get frozen so it will
// be safe to interact with them.
func (b *Bitmap) OffsetRange(offset, start, end uint64) *Bitmap {
if lowbits(offset) != 0 {
panic("offset must not contain low bits")
}
if lowbits(start) != 0 {
panic("range start must not contain low bits")
}
if lowbits(end) != 0 {
panic("range end must not contain low bits")
}
off := highbits(offset)
hi0, hi1 := highbits(start), highbits(end)
citer, _ := b.Containers.Iterator(hi0)
other := NewSliceBitmap()
for citer.Next() {
k, c := citer.Value()
if k >= hi1 {
break
}
other.Containers.Put(off+(k-hi0), c.Freeze())
}
return other
}
// container returns the container with the given key.
func (b *Bitmap) container(key uint64) *Container {
return b.Containers.Get(key)
}
// IntersectionCount returns the number of set bits that would result in an
// intersection between b and other. It is more efficient than actually
// intersecting the two and counting the result.
func (b *Bitmap) IntersectionCount(other *Bitmap) uint64 {
var n uint64
iiter, _ := b.Containers.Iterator(0)
jiter, _ := other.Containers.Iterator(0)
i, j := iiter.Next(), jiter.Next()
ki, ci := iiter.Value()
kj, cj := jiter.Value()
for i && j {
if ki < kj {
i = iiter.Next()
ki, ci = iiter.Value()
} else if ki > kj {
j = jiter.Next()
kj, cj = jiter.Value()
} else {
n += uint64(intersectionCount(ci, cj))
i, j = iiter.Next(), jiter.Next()
ki, ci = iiter.Value()
kj, cj = jiter.Value()
}
}
return n
}
// Intersect returns the intersection of b and other.
func (b *Bitmap) Intersect(other *Bitmap) *Bitmap {
output := NewBitmap()
iiter, _ := b.Containers.Iterator(0)
jiter, _ := other.Containers.Iterator(0)
i, j := iiter.Next(), jiter.Next()
ki, ci := iiter.Value()
kj, cj := jiter.Value()
for i && j {
if ki < kj {
i = iiter.Next()
ki, ci = iiter.Value()
} else if ki > kj {
j = jiter.Next()
kj, cj = jiter.Value()
} else { // ki == kj
newC := intersect(ci, cj)
output.Containers.Put(ki, newC)
i, j = iiter.Next(), jiter.Next()
ki, ci = iiter.Value()
kj, cj = jiter.Value()
}
}
return output
}
func (b *Bitmap) Hash(hash uint64) uint64 {
const (
offset = 14695981039346656037
prime = 1099511628211
)
if hash == 0 {
hash = uint64(offset)
}
it, _ := b.Containers.Iterator(0)
for it.Next() {
ki, _ := it.Value()
hash ^= uint64(ki)
hash *= prime
}
it, _ = b.Containers.Iterator(0)
for it.Next() {
_, ci := it.Value()
hash ^= 0
hash *= prime
if ci.N() > 0 {
var bytes []byte
switch ci.typ() {
case ContainerArray:
bytes = fromArray16(ci.array())
case ContainerBitmap:
bytes = fromArray64(ci.bitmap())
case ContainerRun:
bytes = fromInterval16(ci.runs())
}
for _, b := range bytes {
hash ^= uint64(b)
hash *= prime
}
}
}
return hash
}
type mutableContainersIterator struct {
c Containers
cit ContainerIterator
sit *sliceIterator
}
func newMutableContainersIterator(cs Containers, key uint64) *mutableContainersIterator {
it := &mutableContainersIterator{c: cs}
if sc, ok := cs.(*sliceContainers); ok {
if i, found := sc.seek(key); found {
it.sit = &sliceIterator{e: sc, i: i, index: i}
return it
}
}
it.cit, _ = cs.Iterator(key)
return it
}
func (it *mutableContainersIterator) update(key uint64, newCont *Container) {
if it.sit != nil {
if key == it.sit.key {
it.sit.e.containers[it.sit.index] = newCont
}
}
it.c.Update(key, func(_ *Container, _ bool) (*Container, bool) {
return newCont, true
})
}
func (it *mutableContainersIterator) Next() bool {
if it.sit != nil {
return it.sit.Next()
}
return it.cit.Next()
}
func (it *mutableContainersIterator) Value() (uint64, *Container) {
if it.sit != nil {
return it.sit.Value()
}
return it.cit.Value()
}
func (it *mutableContainersIterator) Close() {}
// IntersectInPlace returns the bitwise intersection of b and others,
// modifying b in place.
func (b *Bitmap) IntersectInPlace(others ...*Bitmap) {
var bSize int
if bSize = b.Size(); bSize == 0 {
// If b doesn't have any containers then return early.
return
}
otherIters := make(handledIters, 0, len(others))
for _, other := range others {
it, _ := other.Containers.Iterator(0)
if !it.Next() {
// An empty bitmap - reset all
b.Containers.Reset()
return
}
otherIters = append(otherIters, handledIter{
iter: it,
hasNext: true,
})
}
bIter := newMutableContainersIterator(b.Containers, 0)
for bIter.Next() {
bKey, bCont := bIter.Value()
if bCont.N() == 0 {
// No point in intersecting things from an empty container.
bIter.update(bKey, nil)
continue
}
// Loop until every iters current value has been handled.
for _, otherIter := range otherIters {
if !otherIter.hasNext {
continue
}
otherKey, otherCont := otherIter.iter.Value()
for otherKey < bKey {
otherIter.hasNext = otherIter.iter.Next()
if !otherIter.hasNext {
break
}
otherKey, otherCont = otherIter.iter.Value()
}
if bKey == otherKey {
// Note: a nil container is valid, and has N == 0.
if otherCont.N() != 0 {
if bCont.frozen() {
bCont = bCont.Clone()
b.Containers.Put(bKey, bCont)
}
bCont = bCont.intersectInPlace(otherCont)
bIter.update(bKey, bCont)
if bCont == nil || bCont.N() == 0 {
break
}
otherIter.hasNext = otherIter.iter.Next()
continue
}
}
bIter.update(bKey, nil)
break
}
}
b.Containers.Repair()
}
func (c *Container) intersectInPlace(other *Container) *Container {
// short-circuit the trivial cases
if c == nil || other == nil || c.N() == 0 || other.N() == 0 {
c = nil
return c
}
cFull, otherFull := (c.N() == MaxContainerVal+1), (other.N() == MaxContainerVal+1)
if cFull && otherFull {
return c
}
if cFull {
return c.copyInPlace(other)
}
if otherFull {
return c
}
switch c.typ() {
case ContainerArray:
switch other.typ() {
case ContainerArray:
return intersectArrayArrayInPlace(c, other)
case ContainerBitmap:
return intersectArrayBitmapInPlace(c, other)
case ContainerRun:
return intersectArrayRunInPlace(c, other)
}
case ContainerBitmap:
switch other.typ() {
case ContainerArray:
return intersectBitmapArrayInPlace(c, other)
case ContainerBitmap:
return intersectBitmapBitmapInPlace(c, other)
case ContainerRun:
return intersectBitmapRunInPlace(c, other)
}
case ContainerRun:
switch other.typ() {
case ContainerArray:
return intersectRunArrayInPlace(c, other)
case ContainerBitmap:
return intersectRunBitmapInPlace(c, other)
case ContainerRun:
return intersectRunRunInPlace(c, other)
}
}
panic(fmt.Errorf("invalid intersect op: unknown types %d/%d", c.typ(), other.typ()))
}
func (c *Container) copyInPlace(other *Container) *Container {
switch other.typ() {
case ContainerArray:
c.setTyp(ContainerArray)
c.setArrayMaybeCopy(other.array(), true)
case ContainerBitmap:
c.setTyp(ContainerBitmap)
c.setBitmapCopy(other.bitmap())
c.setN(other.N())
case ContainerRun:
c.setTyp(ContainerRun)
c.setRunsMaybeCopy(other.runs(), true)
c.setN(other.N())
default:
panic(fmt.Errorf("invalid container type: %v", c.typ()))
}
return c
}
func intersectArrayArrayInPlace(a, b *Container) *Container {
statsHit("intersectInPlace/ArrayArray")
a = a.Thaw()
aa, ba := a.array(), b.array()
an, bn := len(aa), len(ba)
n := 0
for i, j := 0, 0; i < an && j < bn; {
va, vb := aa[i], ba[j]
if va < vb {
i++
} else if va > vb {
j++
} else {
aa[n] = va
n, i, j = n+1, i+1, j+1
}
}
aa = aa[:n]
a.setArray(aa)
return a
}
func intersectArrayRunInPlace(a, b *Container) *Container {
statsHit("intersectInPlace/ArrayRun")
a = a.Thaw()
aa, br := a.array(), b.runs()
an, bn := len(aa), len(br)
n := 0
for i, j := 0, 0; i < an && j < bn; {
va, vb := aa[i], br[j]
if va < vb.Start {
i++
} else if va > vb.Last {
j++
} else {
aa[n] = va
n++
i++
}
}
aa = aa[:n]
a.setArray(aa)
return a
}
func intersectArrayBitmapInPlace(a, b *Container) *Container {
statsHit("intersectInPlace/ArrayBitmap")
a = a.Thaw()
aa := a.array()
bb := b.bitmap()
n := 0
for _, va := range aa {
b := bb[va>>6]
bidx := va % 64
mask := uint64(1) << bidx
if b&mask > 0 {
aa[n] = va
n++
}
}
aa = aa[:n]
a.setArray(aa)
return a
}
func intersectBitmapBitmapInPlace(a, b *Container) *Container {
statsHit("intersectInPlace/BitmapBitmap")
a = a.Thaw()
ab := a.bitmap()[:bitmapN]
bb := b.bitmap()[:bitmapN]
n := int32(0)
for i := 0; i < bitmapN; i += 4 {
// unrolling is still effective in go
// TODO: the generated machine code is extremely bad here, because we are forcing the compiler to reload ab immediately after storing it
// The body of the loop has a total of 8 branches: 4 bounds checks + 4 feature checks.
// We could substantially improve this by converting the entire bitmap to [256][4]uint64.
ptr := (*[4]uint64)(unsafe.Pointer(&bb[i]))
ab[i] &= ptr[0]
ab[i+1] &= ptr[1]
ab[i+2] &= ptr[2]
ab[i+3] &= ptr[3]
n += int32(popcount(ab[i])) +
int32(popcount(ab[i+1])) +
int32(popcount(ab[i+2])) +
int32(popcount(ab[i+3]))
}
a.setN(n)
return a
}
func intersectBitmapArrayInPlace(a, b *Container) *Container {
statsHit("intersectInPlace/BitmapArray")
a = a.Thaw()
ab := a.bitmap()
ba := b.array()
bn := len(ba)
array := make([]uint16, bn)
n := int32(0)
for _, vb := range ba {
i := vb >> 6
mask := uint64(1) << uint(vb%64)
if ab[i]&mask > 0 {
array[n] = vb
n++
}
}
array = array[:n]
a.setTyp(ContainerArray)
a.setArray(array)
return a
}
func intersectBitmapRunInPlace(a, b *Container) *Container {
statsHit("intersectInPlace/BitmapRun")
a = a.Thaw()
ab := a.bitmap()
br := b.runs()
an := len(ab)
bitmap := make([]uint64, an)
n := int32(0)
for _, vb := range br {
i := vb.Start >> 6 // index into a
vastart := i << 6
valast := vastart + 63
for valast >= vb.Start && vastart <= vb.Last && int(i) < an {
if vastart >= vb.Start && valast <= vb.Last { // a within b
bitmap[i] = ab[i]
n += int32(popcount(ab[i]))
} else if vb.Start >= vastart && vb.Last <= valast { // b within a
var mask uint64 = ((1 << (vb.Last - vb.Start + 1)) - 1) << (vb.Start - vastart)
bits := ab[i] & mask
bitmap[i] |= bits
n += int32(popcount(bits))
} else if vastart < vb.Start { // a overlaps front of b
offset := 64 - (1 + valast - vb.Start)
bits := (ab[i] >> offset) << offset
bitmap[i] |= bits
n += int32(popcount(bits))
} else if vb.Start < vastart { // b overlaps front of a
offset := 64 - (1 + vb.Last - vastart)
bits := (ab[i] << offset) >> offset
bitmap[i] |= bits
n += int32(popcount(bits))
}
i++
vastart = i << 6
valast = vastart + 63
}
}
a.setBitmap(bitmap)
a.setN(n)
return a
}
func intersectRunRunInPlace(a, b *Container) *Container {
statsHit("intersectInPlace/RunRun")
a = a.Thaw()
ar, br := a.runs(), b.runs()
an, bn := len(ar), len(br)
var runs []Interval16
if an > bn {
runs = make([]Interval16, 0, an)
} else {
runs = make([]Interval16, 0, bn)
}
n := int32(0)
for i, j := 0, 0; i < an && j < bn; {
va, vb := ar[i], br[j]
if va.Last < vb.Start {
// |--va--| |--vb--|
i++
} else if vb.Last < va.Start {
// |--vb--| |--va--|
j++
} else if va.Last > vb.Last && va.Start >= vb.Start {
// |--vb-|-|-va--|
runs = append(runs, Interval16{Start: va.Start, Last: vb.Last})
n += int32(vb.Last-va.Start) + 1
j++
} else if va.Last > vb.Last && va.Start < vb.Start {
// |--va|--vb--|--|
runs = append(runs, vb)
n += int32(vb.Last-vb.Start) + 1
j++
} else if va.Last <= vb.Last && va.Start >= vb.Start {
// |--vb|--va--|--|
runs = append(runs, va)
n += int32(va.Last-va.Start) + 1
i++
} else if va.Last <= vb.Last && va.Start < vb.Start {
// |--va-|-|-vb--|
runs = append(runs, Interval16{Start: vb.Start, Last: va.Last})
n += int32(va.Last-vb.Start) + 1
i++
}
}
a.setRuns(runs)
a.setN(n)
return a
}
func intersectRunArrayInPlace(a, b *Container) *Container {
statsHit("intersectInPlace/RunArray")
a = a.Thaw()
ar, ba := a.runs(), b.array()
an, bn := len(ar), len(ba)
array := make([]uint16, bn)
n := 0
for i, j := 0, 0; i < an && j < bn; {
va, vb := ar[i], ba[j]
if vb < va.Start {
j++
} else if vb > va.Last {
i++
} else {
array[n] = vb
n++
j++
}
}
array = array[:n]
a.setTyp(ContainerArray)
a.setArray(array)
return a
}
func intersectRunBitmapInPlace(a, b *Container) *Container {
statsHit("intersectInPlace/RunBitmap")
// TODO(@kuba--):
// Figure out how to efficiently intersect dense runs with bitmaps.
// So far we convert run to bitmap and intersect bitmaps - it's much faster
// than naive O(n^2) algorithm.
a = a.runToBitmap()
return intersectBitmapBitmapInPlace(a, b)
}
// Union returns the bitwise union of b and others as a new bitmap.
func (b *Bitmap) Union(others ...*Bitmap) *Bitmap {
if len(others) == 1 {
output := NewBitmap()
b.unionIntoTargetSingle(output, others[0])
return output
}
// It may seem counterintuitive to freeze this, but the result is
// a new bitmap which can be safely modified, but postponing any
// allocations until an actual write to any given container.
output := b.Freeze()
output.UnionInPlace(others...)
return output
}
// UnionInPlace returns the bitwise union of b and others, modifying
// b in place.
func (b *Bitmap) UnionInPlace(others ...*Bitmap) {
b.unionInPlace(others...)
}
func (b *Bitmap) unionIntoTargetSingle(target *Bitmap, other *Bitmap) {
iiter, _ := b.Containers.Iterator(0)
jiter, _ := other.Containers.Iterator(0)
i, j := iiter.Next(), jiter.Next()
ki, ci := iiter.Value()
kj, cj := jiter.Value()
for i || j {
if i && (!j || ki < kj) {
target.Containers.Put(ki, ci.Freeze())
i = iiter.Next()
ki, ci = iiter.Value()
} else if j && (!i || ki > kj) {
target.Containers.Put(kj, cj.Freeze())
j = jiter.Next()
kj, cj = jiter.Value()
} else { // ki == kj
newC := union(ci, cj)
target.Containers.Put(ki, newC)
i, j = iiter.Next(), jiter.Next()
ki, ci = iiter.Value()
kj, cj = jiter.Value()
}
}
}
// unionInPlace stores the union of b and others into b. The others will
// be left unchanged.
//
// This function performs an n-way union of n bitmaps. It performs this in an
// optimized manner looping through all the bitmaps and performing unions one
// container at a time. As a result, instead of generating many intermediary
// containers for each union operation for a given container key, only one
// new container needs to be allocated (or re-used) regardless of how many bitmaps
// participate in the union. This significantly reduces allocations. In addition,
// because we perform the unions one container at a time across all the bitmaps, we
// can calculate summary statistics that allow us to make more efficient decisions
// up front. For instance, if we have a non-bitmap target container, but we
// expect more than ArrayMaxSize bits, we can convert to bitmap preemptively.
// This will sometimes be wrong (we can't really tell how many bits we'll have
// after a union) but is probably close enough to be useful. This will save
// some reallocations for cases where several consecutive ops have array
// representations, and we expect to have to convert to a bitmap eventually;
// we don't allocate larger and larger array slices before doing that.
//
// An additional optimization that this function makes is that it recognizes that even when
// CPU support is present, performing the popcount() operation isn't free. Imagine a scenario
// where 10 bitset containers are being unioned together one after the next. If every
// bitset<->bitset union operation needs to keep the containers' cardinality up to date, then
// the algorithm will waste a lot of time performing intermediary popcount() operations that
// will immediately be invalidated by the next union operation. As a result, we allow the cardinality
// of containers to degrade when we perform the in-place union operations, and then when the algorithm
// completes we "repair" all the containers by performing the popcount() operation one time. This means
// that we only ever have to do O(1) popcount operations per container instead of O(n) where n is the
// number of containers with the same key that are being unioned together.
//
// The algorithm works by iterating through all of the containers in all of the bitmaps concurrently.
// At every "tick" of the outermost loop, we increment our pointer into the bitmaps list of containers
// by 1 (if we haven't reached the end of the containers for that bitmap.)
//
// We then loop through all of the "current" values(containers) for all of the bitmaps
// and for each container with a specific key that we encounter, we scan forward to see if any of the
// other bitmaps have a container for the same key. If so, we calculate some summary statistics and
// then use that information to make a decision about how to union all of the containers with the same
// key together, perform the union, mark the unioned containers as "handled" and then move on to the next
// batch of containers that share the same key.
//
// We repeat this process until every single bitmaps current container has been "handled". Then we start the
// outer loop over again and the process repeats until we've iterated through every container in every bitmap
// and unioned everything into a single target bitmap.
//
// The diagram below shows the iteration state of four different bitmaps as the algorithm progresses them.
// The diagrams should BE interpreted from left -> right, top -> bottom. The X's represent a container in
// the bitmap at a specific key, ^ symbol represents the bitmaps current container iteration position,
// and the - symbol represents a container that is at the current iteration position, but has been marked as "handled".
//
// ---------------------------- | ---------------------------- | ----------------------------
//
// Bitmap 1 |___X____________X__________| | |___X____________X__________| | |___X____________X__________|
//
// ^ | _ |
// ---------------------------- | ---------------------------- | ----------------------------
//
// Bitmap 2 |_______X________X______X___| | |_______X_______________X___| | |_______X_______________X___|
//
// ^ | ^ |
// ---------------------------- | ---------------------------- | ----------------------------
//
// Bitmap 3 |_______X___________________| | |_______X___________________| | |_______X___________________|
//
// ^ | ^ |
// ---------------------------- | ---------------------------- | ----------------------------
//
// Bitmap 4 |___X_______________________| | |___X_______________________| | |___X_______________________|
//
// ^ | _ |
//
// ------------------------------------------------------------------------------------------------------------------------
//
// ---------------------------- | ---------------------------- | ----------------------------
//
// Bitmap 1 |___X____________X__________| | |___X____________X__________| | |___X____________X__________|
//
// _ | ^ | _
// ---------------------------- | ---------------------------- | ----------------------------
//
// Bitmap 2 |_______X_______________X___| | |_______X_______________X___| | |_______X_______________X___|
//
// _ | ^ | ^
// ---------------------------- | ---------------------------- | ----------------------------
//
// Bitmap 3 |_______X___________________| | |_______X___________________| | |_______X___________________|
//
// _ | |
// ---------------------------- | ---------------------------- | ----------------------------
//
// Bitmap 4 |___X_______________________| | |___X_______________________| | |___X_______________________|
//
// _
func (b *Bitmap) unionInPlace(others ...*Bitmap) {
const staticSize = 20
var (
requiredSliceSize = len(others)
// To avoid having to allocate a slice every time, if the number of bitmaps
// being unioned is small enough (i.e. smaller than staticSize), we can just
// use this stack-allocated array.
staticHandledIters = [staticSize]handledIter{}
bitmapIters handledIters
target = b
)
if requiredSliceSize <= staticSize {
bitmapIters = staticHandledIters[:0]
} else {
bitmapIters = make(handledIters, 0, requiredSliceSize)
}
for _, other := range others {
otherIter, _ := other.Containers.Iterator(0)
if otherIter.Next() {
bitmapIters = append(bitmapIters, handledIter{
iter: otherIter,
hasNext: true,
handled: false,
})
}
}
// Loop until we've exhausted every iter.
hasNext := true
for hasNext {
// Loop until every iters current value has been handled.
for i, iIter := range bitmapIters {
if !iIter.hasNext || iIter.handled {
// Either we've exhausted this iter (it has no more containers), or
// we've already handled the current container by unioning it with
// one of the containers we encountered earlier.
continue
}
iKey, iContainer := iIter.iter.Value()
expectedN := int64(0)
// determine whether we have a target to union into.
tContainer := target.Containers.Get(iKey)
// if the target's full, short-circuit out.
if tContainer != nil {
tN, ok := tContainer.SafeN()
if ok && tN == MaxContainerVal+1 {
bitmapIters.markItersWithKeyAsHandled(i, iKey)
continue
}
expectedN = int64(tN)
}
// Check i and later iters for any max-range containers, and
// find out how many there are.
summaryStats := bitmapIters[i:].calculateSummaryStats(iKey)
if summaryStats.hasMaxRange {
// One (or more) of the containers represented the maximum possible
// range that a container can store, so instead of calculating a
// union we can generate an RLE container that represents the entire
// range.
tContainer = fullContainer
target.Containers.Put(iKey, tContainer)
bitmapIters.markItersWithKeyAsHandled(i, iKey)
continue
}
expectedN += summaryStats.n
var itersToUnion handledIters
// Overview: We know that we have at least one "other" container
// to union in, and we may have a target container already. We want
// to shortcut easy cases ("no target container, exactly one
// other container").
if tContainer == nil {
// No existing target container.
if summaryStats.c == 1 {
// There's no target and we have only one container, we
// can just reuse it instead of unioning.
statsHit("unionInPlace/reuse")
target.Containers.Put(iKey, iContainer.Freeze())
bitmapIters[i].handled = true
continue
}
// We have at least two other containers. We can union
// everything together. We can union everything but
// the first other container into a clone of the
// first other container, but for some cases, that will
// result in cloning a non-bitmap, then converting it
// to a bitmap, and this will be expensive...
if expectedN >= 512 && iContainer.typ() != ContainerBitmap {
// copying the non-bitmap, then converting it,
// is expensive.
statsHit("unionInPlace/newBitmap")
tContainer = NewContainerBitmapN(nil, 0)
itersToUnion = bitmapIters[i:]
} else {
// either N will be small or iContainer is a
// bitmap, so we can skip one union op by copying it.
// And we can just freeze it, and the copy will
// happen later if it's needed...
statsHit("unionInPlace/clone")
tContainer = iContainer.Freeze()
itersToUnion = bitmapIters[i+1:]
}
} else {
// we have an existing target container. If we're
// going to end up wanting it to be a bitmap, we
// convert it preemptively, because union into a
// bitmap is nearly always faster.
itersToUnion = bitmapIters[i:]
if expectedN >= 512 && tContainer.typ() != ContainerBitmap {
statsHit("unionInPlace/convertToBitmap")
switch tContainer.typ() {
case ContainerArray:
tContainer = tContainer.arrayToBitmap()
case ContainerRun:
tContainer = tContainer.runToBitmap()
}
}
}
// Now we union all remaining containers with this key
// together.
for j, iter := range itersToUnion {
jKey, jContainer := iter.iter.Value()
if iKey == jKey {
tContainer = tContainer.unionInPlace(jContainer)
// "iter" is a local copy from the range
// loop, not the actual slice member.
itersToUnion[j].handled = true
}
}
// Now that we've calculated a container that is a union of all the containers
// with the same key across all the bitmaps, we store it in the list of containers
// for the target.
target.Containers.Put(iKey, tContainer)
}
hasNext = bitmapIters.next()
}
// Performing the popcount() operation with every union is wasteful because
// its likely the value will be invalidated by the next union operation. As
// a result, when we're performing all of our in-place unions we allow the value of
// n (container cardinality) to fall out of sync, and then at the very end we perform
// a "Repair" to recalculate all the container values. That way we never popcount()
// an entire bitmap container more than once per bulk union operation.
target.Containers.Repair()
}
// Difference returns the difference of b and other.
func (b *Bitmap) Difference(other ...*Bitmap) *Bitmap {
output := b.singleDifference(other[0])
if len(other) > 1 {
output.DifferenceInPlace(other[1:]...)
}
return output
}
func (b *Bitmap) singleDifference(other *Bitmap) *Bitmap {
output := NewBitmap()
iiter, _ := b.Containers.Iterator(0)
jiter, _ := other.Containers.Iterator(0)
i, j := iiter.Next(), jiter.Next()
ki, ci := iiter.Value()
kj, cj := jiter.Value()
for i || j {
if i && (!j || ki < kj) {
output.Containers.Put(ki, ci.Freeze())
i = iiter.Next()
ki, ci = iiter.Value()
} else if j && (!i || ki > kj) {
j = jiter.Next()
kj, cj = jiter.Value()
} else { // ki == kj
output.Containers.Put(ki, difference(ci, cj))
i, j = iiter.Next(), jiter.Next()
ki, ci = iiter.Value()
kj, cj = jiter.Value()
}
}
return output
}
// Xor returns the bitwise exclusive or of b and other.
func (b *Bitmap) Xor(other *Bitmap) *Bitmap {
output := NewBitmap()
iiter, _ := b.Containers.Iterator(0)
jiter, _ := other.Containers.Iterator(0)
i, j := iiter.Next(), jiter.Next()
ki, ci := iiter.Value()
kj, cj := jiter.Value()
for i || j {
if i && (!j || ki < kj) {
output.Containers.Put(ki, ci.Freeze())
i = iiter.Next()
ki, ci = iiter.Value()
} else if j && (!i || ki > kj) {
output.Containers.Put(kj, cj.Freeze())
j = jiter.Next()
kj, cj = jiter.Value()
} else { // ki == kj
output.Containers.Put(ki, xor(ci, cj))
i, j = iiter.Next(), jiter.Next()
ki, ci = iiter.Value()
kj, cj = jiter.Value()
}
}
return output
}
// Shift shifts the contents of b by 1.
//
// NOTE: This method is unsupported. See the `Shift()`
// method on `Row` in `row.go`.
func (b *Bitmap) Shift(n int) (*Bitmap, error) {
if n != 1 {
return nil, errors.New("cannot shift by a value other than 1")
}
output := NewBitmap()
iiter, _ := b.Containers.Iterator(0)
lastCarry := false
lastKey := uint64(0)
for iiter.Next() {
ki, ci := iiter.Value()
if lastCarry && ki > lastKey+1 {
extra := NewContainerArray([]uint16{0})
output.Containers.Put(lastKey+1, extra)
lastCarry = false
}
o, carry := shift(ci)
if lastCarry {
o, _ = o.add(0)
}
if o.N() > 0 {
output.Containers.Put(ki, o)
}
lastCarry = carry
lastKey = ki
}
// As long as the carry wasn't from the max container,
// append a new container and add the carried bit.
if lastCarry && lastKey != maxContainerKey {
extra := NewContainerArray([]uint16{0})
output.Containers.Put(lastKey+1, extra)
}
return output, nil
}
// removeEmptyContainers deletes all containers that have a count of zero.
func (b *Bitmap) removeEmptyContainers() {
citer, _ := b.Containers.Iterator(0)
for citer.Next() {
k, c := citer.Value()
if c.N() == 0 {
b.Containers.Remove(k)
}
}
}
func (b *Bitmap) countNonEmptyContainers() int {
result := 0
citer, _ := b.Containers.Iterator(0)
for citer.Next() {
_, c := citer.Value()
if c.N() > 0 {
result++
}
}
return result
}
// Optimize converts array and bitmap containers to run containers as necessary.
func (b *Bitmap) Optimize() {
b.Containers.UpdateEvery(func(key uint64, c *Container, existed bool) (*Container, bool) {
return c.optimize(), true
})
}
type errWriter struct {
w io.Writer
err error
n int
}
func (ew *errWriter) WriteUint16(b []byte, v uint16) {
if ew.err != nil {
return
}
var n int
binary.LittleEndian.PutUint16(b, v)
n, ew.err = ew.w.Write(b)
ew.n += n
}
func (ew *errWriter) WriteUint32(b []byte, v uint32) {
if ew.err != nil {
return
}
var n int
binary.LittleEndian.PutUint32(b, v)
n, ew.err = ew.w.Write(b)
ew.n += n
}
func (ew *errWriter) WriteUint64(b []byte, v uint64) {
if ew.err != nil {
return
}
var n int
binary.LittleEndian.PutUint64(b, v)
n, ew.err = ew.w.Write(b)
ew.n += n
}
// WriteTo writes b to w.
func (b *Bitmap) WriteTo(w io.Writer) (n int64, err error) {
b.Optimize()
return b.writeToUnoptimized(w)
}
// writeToUnoptimized is a WriteTo without the Optimize path. We need
// this because otherwise we can't do some of our marshal/unmarshal tests
// safely.
func (b *Bitmap) writeToUnoptimized(w io.Writer) (n int64, err error) {
// Remove empty containers before persisting.
//b.removeEmptyContainers()
containerCount := b.countNonEmptyContainers()
byte2 := make([]byte, 2)
byte4 := make([]byte, 4)
byte8 := make([]byte, 8)
// Build header before writing individual container blocks.
// Metadata for each container is 8+2+2+4 = sizeof(key) + sizeof(type)+sizeof(cardinality) + sizeof(file offset)
// Type is stored as 2 bytes, even though it's only got values 1..3.
// Cookie header section.
ew := &errWriter{
w: w,
n: 0,
}
ew.WriteUint32(byte4, cookie|(uint32(b.Flags)<<24))
ew.WriteUint32(byte4, uint32(containerCount))
// Descriptive header section: encode keys and cardinality.
// Key and cardinality are stored interleaved here, 12 bytes per container.
citer, _ := b.Containers.Iterator(0)
for citer.Next() {
key, c := citer.Value()
// Verify container count before writing.
// TODO: instead of commenting this out, we need to make it a configuration option
//count := c.count()
//assert(c.count() == c.n, "cannot write container count, mismatch: count=%d, n=%d", count, c.n)
if c.N() > 0 {
ew.WriteUint64(byte8, key)
ew.WriteUint16(byte2, uint16(c.typ()))
ew.WriteUint16(byte2, uint16(c.N()-1))
}
}
if ew.n != headerBaseSize+(containerCount*12) {
return int64(ew.n), fmt.Errorf("after writing %d headers, wrote %d bytes, expected %d",
containerCount, ew.n, headerBaseSize+(containerCount*12))
}
// Offset header section: write the offset for each container block.
// 4 bytes per container. The actual data offsets will then be 4 bytes
// further in per non-empty container, and now that we've scanned the
// containers, we know how many we really have.
offset := uint32(ew.n + (containerCount * 4))
citer, _ = b.Containers.Iterator(0)
for citer.Next() {
_, c := citer.Value()
if c.N() > 0 {
ew.WriteUint32(byte4, offset)
offset += uint32(c.size())
}
}
if ew.err != nil {
return int64(ew.n), ew.err
}
if ew.n != headerBaseSize+(containerCount*16) {
return int64(ew.n), fmt.Errorf("after writing %d headers+offsets, wrote %d bytes, expected %d",
containerCount, ew.n, headerBaseSize+(containerCount*16))
}
// We could compute the expected value, but a SliceContainers can contain
// a nil *Container, reported by Size() but not returned by the iterator.
n = int64(ew.n)
// Container storage section: write each container block.
citer, _ = b.Containers.Iterator(0)
for citer.Next() {
_, c := citer.Value()
if c.N() > 0 {
nn, err := c.WriteTo(w)
n += nn
if err != nil {
return n, err
}
}
}
return n, nil
}
// NewContainerIterator takes a byte slice which is either standard
// roaring or pilosa roaring and returns a ContainerIterator.
func NewContainerIterator(data []byte) (ContainerIterator, error) {
if len(data) == 0 {
return nopContainerIterator{}, nil
}
ri, err := NewRoaringIterator(data)
if err != nil {
return nil, errors.Wrap(err, "getting roaring iterator")
}
return &containerIteratorRoaringIteratorWrapper{
r: ri,
}, nil
}
// containerIteratorRoaringIteratorWrapper wraps a RoaringIterator to
// make it play like a ContainerIterator.
type containerIteratorRoaringIteratorWrapper struct {
r RoaringIterator
nextKey uint64
nextCont *Container
}
func (c *containerIteratorRoaringIteratorWrapper) Next() bool {
c.nextKey, c.nextCont = c.r.NextContainer()
return c.nextCont != nil
}
func (c *containerIteratorRoaringIteratorWrapper) Value() (uint64, *Container) {
return c.nextKey, c.nextCont
}
func (c *containerIteratorRoaringIteratorWrapper) Close() {}
// RoaringIterator represents something which can iterate through a roaring
// bitmap and yield information about containers, including type, size, and
// the location of their data structures.
type RoaringIterator interface {
// Len reports the number of containers total.
Len() (count int64)
// Next yields the information about the next container
Next() (key uint64, cType byte, n int, length int, pointer *uint16, err error)
// Remaining yields the bytes left over past the end of the roaring data,
// which is typically an ops log in our case, and also its offset in case
// we need to talk about truncation.
Remaining() ([]byte, int64)
// NextContainer is a helper that is used in place of Next(). It will
// allocate a Container from the output of its internal call to Next(),
// and return the key and container rc. If Next returns an error, then
// NextContainer will return 0, nil.
// TODO: have this reuse the *Container?
NextContainer() (key uint64, rc *Container)
// Data returns the underlying data, esp for the Ops log.
Data() []byte
// Clone copies the iterator, preserving it at this point in the iteration.
// It may well share much underlying data.
Clone() RoaringIterator
// ContainerKeys provides all the
// container keys that the iterator will return.
// The current implementation requires that the underlying header
// lists the keys in ascending order.
// If there are no keys, then an empty slice will be returned.
ContainerKeys() (slc []uint64)
// Skip will move the iterator forward by 1 without
// materializing the container.
Skip()
}
// baseRoaringIterator holds values used by both Pilosa and official Roaring
// iterators.
type baseRoaringIterator struct {
data []byte
keys int64
headers []byte
offsets []byte
currentKey uint64
currentIdx int64
currentType byte
currentN int
currentLen int
currentPointer *uint16
currentDataOffset uint64
prevOffset32 uint32
chunkOffset uint64
lastDataOffset int64
lastErr error
}
// okay, then
func (b *baseRoaringIterator) SilenceLint() {
// these are actually used in pilosaRoaringIterator or officialRoaringIterator
// but structcheck doesn't know that
_ = b.data
_ = b.keys
_ = b.offsets
_ = b.headers
_ = b.currentIdx
_ = b.chunkOffset
_ = b.prevOffset32
}
func (b *pilosaRoaringIterator) Clone() (clone RoaringIterator) {
cp := *b
return &cp
}
func (b *officialRoaringIterator) Clone() (clone RoaringIterator) {
cp := *b
return &cp
}
type pilosaRoaringIterator struct {
baseRoaringIterator
}
type officialRoaringIterator struct {
baseRoaringIterator
containerTyper func(index uint, card int) byte
haveRuns bool
}
func newOfficialRoaringIterator(data []byte) (*officialRoaringIterator, error) {
r := &officialRoaringIterator{}
r.data = data
// share code with the existing unmarshal code
var offsetOffset, headerOffset int
var err error
var keys uint32
// we ignore the flags, since we don't have to process them for anything.
keys, r.containerTyper, headerOffset, offsetOffset, r.haveRuns, err = readOfficialHeader(data)
if err != nil {
return nil, fmt.Errorf("reading official header: %v", err)
}
if keys == 0 {
// not an error, exactly. it's valid and well-formed, we just have nothing to do
r.Done(io.EOF)
return r, nil
}
r.keys = int64(keys)
r.headers = data[headerOffset:offsetOffset]
// note: offsets are only actually used with the no-run headers.
if r.haveRuns {
r.currentDataOffset = uint64(offsetOffset)
} else {
if len(r.data) < offsetOffset+int(r.keys*4) {
return nil, fmt.Errorf("insufficient data for offsets (need %d bytes, found %d)",
r.keys*4, len(r.data)-offsetOffset)
}
r.offsets = data[offsetOffset : offsetOffset+int(r.keys*4)]
r.currentDataOffset = uint64(offsetOffset)
}
// set key to -1; user should call Next first.
r.currentIdx = -1
r.currentKey = ^uint64(0)
r.lastErr = errors.New("tried to read iterator without calling Next first")
return r, nil
}
func newPilosaRoaringIterator(data []byte) (*pilosaRoaringIterator, error) {
fileVersion := uint32(data[2])
if fileVersion != storageVersion {
return nil, fmt.Errorf("wrong roaring version, file is v%d, server requires v%d", fileVersion, storageVersion)
}
r := &pilosaRoaringIterator{}
r.data = data
// Read key count in bytes sizeof(cookie)+sizeof(flag):(sizeof(cookie)+sizeof(uint32)).
r.keys = int64(binary.LittleEndian.Uint32(data[3+1 : 8]))
// it could happen
if r.keys == 0 {
// special case: what if we have zero containers, but a valid ops log after them?
// set currentDataOffset so that Done will set lastDataOffset and Remaining() will
// work.
if len(data) > headerBaseSize {
r.currentDataOffset = headerBaseSize
}
// not an error, exactly. it's valid and well-formed, we just have nothing to do
r.Done(io.EOF)
return r, nil
}
if int64(len(data)) < int64(headerBaseSize+(r.keys*16)) {
return nil, fmt.Errorf("insufficient data for header + offsets: want %d bytes, got %d",
headerBaseSize+(r.keys*16), len(data))
}
headerStart := int64(headerBaseSize)
headerEnd := headerStart + (r.keys * 12)
offsetStart := headerEnd
offsetEnd := offsetStart + (r.keys * 4)
r.headers = data[headerStart:headerEnd]
r.offsets = data[offsetStart:offsetEnd]
// if there's no containers, we want to act as though data started at the end
// of the list of offsets, which was also empty, so we don't think the entire thing
// is actually a malformed op
r.prevOffset32 = uint32(offsetEnd)
r.currentDataOffset = uint64(offsetEnd)
// it's possible that there's so many headers that we're actually over
// 4GB into the file already.
r.chunkOffset = r.currentDataOffset &^ ((1 << 32) - 1)
// set key to -1; user should call Next first.
r.currentIdx = -1
r.currentKey = ^uint64(0)
r.lastErr = errors.New("tried to read iterator without calling Next first")
return r, nil
}
func NewRoaringIterator(data []byte) (RoaringIterator, error) {
if len(data) < headerBaseSize {
return nil, errors.New("invalid data: not long enough to be a roaring header")
}
// Verify the first two bytes are a valid MagicNumber, and second two bytes match current storageVersion.
fileMagic := uint32(binary.LittleEndian.Uint16(data[0:2]))
switch fileMagic {
case serialCookie, serialCookieNoRunContainer:
return newOfficialRoaringIterator(data)
case MagicNumber:
return newPilosaRoaringIterator(data)
}
return nil, fmt.Errorf("unknown roaring magic number %d", fileMagic)
}
// Done marks the iterator as complete, recording err as the reason why
func (r *baseRoaringIterator) Done(err error) {
r.lastErr = err
r.currentKey = ^uint64(0)
r.currentType = 0
r.currentN = 0
r.currentLen = 0
r.currentPointer = nil
r.lastDataOffset = int64(r.currentDataOffset)
r.currentDataOffset = 0
}
func (r *pilosaRoaringIterator) ContainerKeys() (slc []uint64) {
n := r.keys
if n == 0 {
return
}
for i := int64(0); i < n; i++ {
beg := i * 12
slc = append(slc, binary.LittleEndian.Uint64(r.headers[beg:beg+8]))
}
return
}
func (r *officialRoaringIterator) ContainerKeys() (slc []uint64) {
n := r.keys
if n == 0 {
return
}
for i := int64(0); i < n; i++ {
beg := i * 4
slc = append(slc, uint64(binary.LittleEndian.Uint16(r.headers[beg:beg+2])))
}
return
}
func (r *baseRoaringIterator) Skip() {
if r.currentIdx >= r.keys {
// we're already done
return
}
r.currentIdx++
if r.currentIdx == r.keys {
// this is the last key. transition state to the finalized state
r.Done(io.EOF)
}
}
// Len() indicates the total number of containers the iterator expects to have.
func (r *baseRoaringIterator) Len() int64 {
return r.keys
}
func (r *baseRoaringIterator) Data() []byte {
return r.data
}
func (r *baseRoaringIterator) Remaining() ([]byte, int64) {
if r.lastDataOffset == 0 {
return nil, 0
}
return r.data[r.lastDataOffset:], r.lastDataOffset
}
func (r *pilosaRoaringIterator) NextContainer() (key uint64, rc *Container) {
itrKey, itrCType, itrN, itrLen, itrPointer, itrErr := r.Next()
if itrErr != nil {
return 0, nil
}
rc = &Container{}
rc.typeID = itrCType
rc.n = int32(itrN)
rc.len = int32(itrLen)
rc.cap = int32(itrLen)
rc.pointer = itrPointer
return itrKey, rc
}
func (r *pilosaRoaringIterator) Next() (key uint64, cType byte, n int, length int, pointer *uint16, err error) {
if r.currentIdx >= r.keys {
// we're already done
return r.Current()
}
r.currentIdx++
if r.currentIdx == r.keys {
// this is the last key. transition state to the finalized state
r.Done(io.EOF)
return r.Current()
}
header := r.headers[r.currentIdx*12:]
r.currentKey = binary.LittleEndian.Uint64(header[0:8])
r.currentType = byte(binary.LittleEndian.Uint16(header[8:10]))
r.currentN = int(binary.LittleEndian.Uint16(header[10:12])) + 1
offset32 := binary.LittleEndian.Uint32(r.offsets[r.currentIdx*4:])
if offset32 < r.prevOffset32 {
r.chunkOffset += (1 << 32)
}
r.prevOffset32 = offset32
r.currentDataOffset = r.chunkOffset + uint64(offset32)
// a run container keeps its data after an initial 2 byte length header
var runCount uint16
if r.currentType == ContainerRun {
runCount = binary.LittleEndian.Uint16(r.data[r.currentDataOffset : r.currentDataOffset+runCountHeaderSize])
r.currentDataOffset += 2
}
if r.currentDataOffset > uint64(len(r.data)) || r.currentDataOffset < headerBaseSize {
r.Done(fmt.Errorf("container %d/%d, key %d, had offset %d, maximum %d",
r.currentIdx, r.keys, r.currentKey, r.currentDataOffset, len(r.data)))
return r.Current()
}
r.currentPointer = (*uint16)(unsafe.Pointer(&r.data[r.currentDataOffset]))
var size int
switch r.currentType {
case ContainerArray:
r.currentLen = r.currentN
size = r.currentLen * 2
case ContainerBitmap:
r.currentLen = 1024
size = 8192
case ContainerRun:
r.currentLen = int(runCount)
size = r.currentLen * 4
}
if int64(r.currentDataOffset)+int64(size) > int64(len(r.data)) {
r.Done(fmt.Errorf("container %d/%d, key %d, had offset %d+%d size, maximum %d",
r.currentIdx, r.keys, r.currentKey, r.currentDataOffset, size, len(r.data)))
return r.Current()
}
r.currentDataOffset += uint64(size)
r.lastErr = nil
return r.Current()
}
func (r *officialRoaringIterator) NextContainer() (key uint64, rc *Container) {
itrKey, itrCType, itrN, itrLen, itrPointer, itrErr := r.Next()
if itrErr != nil {
return 0, nil
}
rc = &Container{}
rc.typeID = itrCType
rc.n = int32(itrN)
rc.len = int32(itrLen)
rc.cap = int32(itrLen)
rc.pointer = itrPointer
return itrKey, rc
}
func (r *officialRoaringIterator) Next() (key uint64, cType byte, n int, length int, pointer *uint16, err error) {
if r.currentIdx >= r.keys {
// we're already done
return r.Current()
}
r.currentIdx++
if r.currentIdx == r.keys {
// this is the last key. transition state to the finalized state
r.Done(io.EOF)
return r.Current()
}
header := r.headers[r.currentIdx*4:]
r.currentKey = uint64(binary.LittleEndian.Uint16(header[0:2]))
r.currentN = int(binary.LittleEndian.Uint16(header[2:4])) + 1
r.currentType = r.containerTyper(uint(r.currentIdx), r.currentN)
// with runs, we can't actually look up offsets; the format just stores
// things sequentially. so we have to actually track the offset in that case.
if !r.haveRuns {
r.currentDataOffset = uint64(binary.LittleEndian.Uint32(r.offsets[r.currentIdx*4:]))
}
// a run container keeps its data after an initial 2 byte length header
var runCount uint16
if r.currentType == ContainerRun {
if int(r.currentDataOffset)+2 > len(r.data) {
r.Done(fmt.Errorf("insufficient data for offsets container %d/%d, expect run length at %d/%d bytes",
r.currentIdx, r.keys, r.currentDataOffset, len(r.data)))
return r.Current()
}
runCount = binary.LittleEndian.Uint16(r.data[r.currentDataOffset : r.currentDataOffset+runCountHeaderSize])
r.currentDataOffset += 2
}
if r.currentDataOffset > uint64(len(r.data)) || r.currentDataOffset < headerBaseSize {
r.Done(fmt.Errorf("container %d/%d, key %d, had offset %d, maximum %d",
r.currentIdx, r.keys, r.currentKey, r.currentDataOffset, len(r.data)))
return r.Current()
}
r.currentPointer = (*uint16)(unsafe.Pointer(&r.data[r.currentDataOffset]))
var size int
switch r.currentType {
case ContainerArray:
r.currentLen = r.currentN
size = r.currentLen * 2
case ContainerBitmap:
r.currentLen = 1024
size = 8192
case ContainerRun:
// official format stores runs as start/len, we want to convert, but since
// they might be mmapped, we can't write to that memory
newRuns := make([]Interval16, runCount)
oldRuns := (*[65536]Interval16)(unsafe.Pointer(r.currentPointer))[:runCount:runCount]
copy(newRuns, oldRuns)
for i := range newRuns {
newRuns[i].Last += newRuns[i].Start
}
r.currentPointer = (*uint16)(unsafe.Pointer(&newRuns[0]))
r.currentLen = int(runCount)
size = r.currentLen * 4
}
if int64(r.currentDataOffset)+int64(size) > int64(len(r.data)) {
r.Done(fmt.Errorf("container %d/%d, key %d, had offset %d+%d size, maximum %d",
r.currentIdx, r.keys, r.currentKey, r.currentDataOffset, size, len(r.data)))
return r.Current()
}
r.currentDataOffset += uint64(size)
r.lastErr = nil
return r.Current()
}
func (r *baseRoaringIterator) Current() (key uint64, cType byte, n int, length int, pointer *uint16, err error) {
return r.currentKey, r.currentType, r.currentN, r.currentLen, r.currentPointer, r.lastErr
}
// SanityCheckMapping is a debugging function which checks whether containers
// are *correctly* recorded as mapped or unmapped.
func (b *Bitmap) SanityCheckMapping(from, to uintptr) (mappedIn int64, mappedOut int64, unmappedIn int64, errs int, err error) {
b.Containers.UpdateEvery(func(key uint64, c *Container, existed bool) (*Container, bool) {
dptr := uintptr(unsafe.Pointer(c.pointer))
if dptr >= from && dptr < to {
if c.Mapped() {
mappedIn++
} else {
err = fmt.Errorf("container key %d, addr %x, inside %x+%d",
key, dptr, from, to-from)
errs++
unmappedIn++
}
} else {
if c.Mapped() {
err = fmt.Errorf("container key %d, addr %x, outside %x+%d, but mapped",
key, dptr, from, to-from)
errs++
mappedOut++
}
}
return c, false
})
return mappedIn, mappedOut, unmappedIn, errs, err
}
// RemapRoaringStorage tries to update all containers to refer to
// the roaring bitmap in the provided []byte. If any containers are
// marked as mapped, but do not match the provided storage, they will
// be unmapped. The boolean return indicates whether or not any
// containers were mapped to the given storage.
//
// Regardless, after this function runs, no containers have
// mapped storage which does not refer to data; either they got mapped
// to the new storage, or storage was allocated for them.
func (b *Bitmap) RemapRoaringStorage(data []byte) (mappedAny bool, returnErr error) {
if b.Containers == nil {
return false, nil
}
var itr RoaringIterator
var err error
var itrKey uint64
var itrCType byte
var itrN int
var itrPointer *uint16
var itrErr error
// If we got no data, we don't want to do the actual mapping, just
// the unmapping. If preferMapping is false, we also don't want to
// map to the data. We still need to do the UpdateEvery loop, we
// just won't have an iterator for it.
if data != nil && b.preferMapping {
itr, err = NewRoaringIterator(data)
}
// don't return early: we still have to do the unmapping
if err != nil {
returnErr = err
}
if itr != nil {
itrKey, itrCType, itrN, _, itrPointer, itrErr = itr.Next()
}
if itrErr != nil {
// iterator errored out, so we won't check it in the loop below
itr = nil
}
b.Containers.UpdateEvery(func(key uint64, oldC *Container, existed bool) (newC *Container, write bool) {
if itr != nil {
for itrKey < key && itrErr == nil {
itrKey, itrCType, itrN, _, itrPointer, itrErr = itr.Next()
}
if itrErr != nil {
itr = nil
}
// container might be similar enough that we should trust it:
if itrKey == key && itrCType == oldC.typ() && itrN == int(oldC.N()) {
if oldC.frozen() {
// we don't use Clone, because that would copy the
// storage, and we don't need that.
halfCopy := *oldC
halfCopy.flags &^= flagFrozen
newC = &halfCopy
} else {
newC = oldC
}
mappedAny = true
newC.pointer = itrPointer
newC.flags |= flagMapped
return newC, true
}
}
// if the container isn't mapped, we don't need to do anything
if !oldC.Mapped() {
return oldC, false
}
// forcibly unmap it, so the old mapping can be unmapped safely.
newC = oldC.unmapOrClone()
return newC, true
})
return mappedAny, returnErr
}
// ImportRoaringBits sets-or-clears bits based on a provided Roaring bitmap.
// This should be equivalent to unmarshalling the bitmap, then executing
// either `b = Union(b, newB)` or `b = Difference(b, newB)`, but with lower
// overhead. The log parameter controls whether to write to the op log; the
// answer should always be yes, except if you're calling using this to apply
// the op log.
//
// If rowSize is non-zero, we should return a map of rows we altered,
// where "rows" are sets of rowSize containers. Otherwise the map isn't used.
// (This allows ImportRoaring to update caches; see fragment.go.)
func (b *Bitmap) ImportRoaringBits(data []byte, clear bool, log bool, rowSize uint64) (changed int, rowSet map[uint64]int, err error) {
if data == nil {
return 0, nil, errors.New("no roaring bitmap provided")
}
var itr RoaringIterator
itr, err = NewRoaringIterator(data)
if err != nil {
return 0, nil, err
}
return b.ImportRoaringRawIterator(itr, clear, log, rowSize)
}
// MergeRoaringRawIteratorIntoExists is a special merge iterator that flattens the results onto a
// single row which is used for determining existence. All row references are removed and only the column
// is considered.
func (b *Bitmap) MergeRoaringRawIteratorIntoExists(itr RoaringIterator, rowSize uint64) error {
if itr == nil {
return errors.New("nil RoaringIterator passed to MergeRoaringRawIteratorIntoExists")
}
var synthC Container
importUpdater := func(oldC *Container, existed bool) (newC *Container, write bool) {
existN := oldC.N()
if existN == MaxContainerVal+1 {
return oldC, false
}
if existN == 0 {
newerC := synthC.Clone()
return newerC, true
}
newC = oldC.unionInPlace(&synthC)
if newC.typeID == ContainerBitmap {
newC.Repair()
}
if newC.N() != existN {
return newC, true
}
return oldC, false
}
itrKey, itrCType, itrN, itrLen, itrPointer, itrErr := itr.Next()
for itrErr == nil {
synthC.typeID = itrCType
synthC.n = int32(itrN)
synthC.len = int32(itrLen)
synthC.cap = int32(itrLen)
synthC.pointer = itrPointer
b.Containers.Update(itrKey%rowSize, importUpdater)
itrKey, itrCType, itrN, itrLen, itrPointer, itrErr = itr.Next()
}
// note: if we get a non-EOF err, it's possible that we made SOME
// changes but didn't log them. I don't have a good solution to this.
if itrErr != io.EOF {
return itrErr
}
return nil
}
func (b *Bitmap) ImportRoaringRawIterator(itr RoaringIterator, clear bool, log bool, rowSize uint64) (changed int, rowSet map[uint64]int, err error) {
var itrKey uint64
var itrCType byte
var itrN int
var itrLen int
var itrPointer *uint16
var itrErr error
if itr == nil {
return 0, nil, errors.New("failed to create roaring iterator, but don't know why")
}
rowSet = make(map[uint64]int)
var synthC Container
var importUpdater func(*Container, bool) (*Container, bool)
var currRow uint64
if clear {
importUpdater = func(oldC *Container, existed bool) (newC *Container, write bool) {
existN := oldC.N()
if existN == 0 || !existed {
return nil, false
}
newC = difference(oldC, &synthC)
if newC.N() != existN {
changes := int(existN - newC.N())
changed += changes
rowSet[currRow] -= changes
return newC, true
}
return oldC, false
}
} else {
importUpdater = func(oldC *Container, existed bool) (newC *Container, write bool) {
existN := oldC.N()
if existN == MaxContainerVal+1 {
return oldC, false
}
if existN == 0 {
newerC := synthC.Clone()
changed += int(newerC.N())
rowSet[currRow] += int(newerC.N())
return newerC, true
}
newC = oldC.unionInPlace(&synthC)
if newC.typeID == ContainerBitmap {
newC.Repair()
}
if newC.N() != existN {
changes := int(newC.N() - existN)
changed += changes
rowSet[currRow] += changes
return newC, true
}
return oldC, false
}
}
itrKey, itrCType, itrN, itrLen, itrPointer, itrErr = itr.Next()
for itrErr == nil {
synthC.typeID = itrCType
synthC.n = int32(itrN)
synthC.len = int32(itrLen)
synthC.cap = int32(itrLen)
synthC.pointer = itrPointer
if rowSize != 0 {
currRow = itrKey / rowSize
}
b.Containers.Update(itrKey, importUpdater)
itrKey, itrCType, itrN, itrLen, itrPointer, itrErr = itr.Next()
}
// note: if we get a non-EOF err, it's possible that we made SOME
// changes but didn't log them. I don't have a good solution to this.
if itrErr != io.EOF {
return changed, rowSet, itrErr
}
err = nil
if log && changed > 0 {
o := op{opN: changed, roaring: itr.Data()}
if clear {
o.typ = opTypeRemoveRoaring
} else {
o.typ = opTypeAddRoaring
}
err = b.writeOp(&o)
}
return changed, rowSet, err
}
func (b *Bitmap) PreferMapping(preferred bool) {
b.preferMapping = preferred
}
// writeOp writes op to the OpWriter, if available.
func (b *Bitmap) writeOp(op *op) error {
if b.OpWriter == nil {
return nil
}
if _, err := op.WriteTo(b.OpWriter); err != nil {
return err
}
b.opN += op.count()
b.ops++
return nil
}
// Iterator returns a new iterator for the bitmap.
func (b *Bitmap) Iterator() *Iterator {
itr := &Iterator{bitmap: b}
itr.Seek(0)
return itr
}
func (b *Bitmap) IteratorAt(start uint64) *Iterator {
itr := &Iterator{bitmap: b}
itr.Seek(start)
return itr
}
// Ops returns the number of write ops the bitmap is aware of in its ops
// log, and their total bit count.
func (b *Bitmap) Ops() (ops int, opN int) {
return b.ops, b.opN
}
// SetOps lets us reset the operation count in the weird case where we know
// we've changed an underlying file, without actually refreshing the bitmap.
func (b *Bitmap) SetOps(ops int, opN int) {
b.ops, b.opN = ops, opN
}
// RoaringToBitmaps yields a series of bitmaps with specified shard
// keys, based on a single roaring file, with splits at multiples of
// shardWidth, which should be a multiple of container size.
func RoaringToBitmaps(data []byte, shardWidth uint64) ([]*Bitmap, []uint64) {
if data == nil {
return nil, nil
}
var itr RoaringIterator
var itrKey uint64
var itrCType byte
var itrN int
var itrLen int
var itrPointer *uint16
var itrErr error
currentShard := ^uint64(0)
var currentBitmap *Bitmap
var bitmaps []*Bitmap
var shards []uint64
keysPerShard := shardWidth >> 16
itr, err := NewRoaringIterator(data)
if err != nil || itr == nil {
return nil, nil
}
itrKey, itrCType, itrN, itrLen, itrPointer, itrErr = itr.Next()
for itrErr == nil {
newC := &Container{
typeID: itrCType,
n: int32(itrN),
len: int32(itrLen),
cap: int32(itrLen),
pointer: itrPointer,
flags: flagMapped,
}
shard := itrKey / keysPerShard
if shard != currentShard {
if currentBitmap != nil {
bitmaps = append(bitmaps, currentBitmap)
shards = append(shards, currentShard)
}
currentBitmap = NewFileBitmap()
currentShard = shard
}
currentBitmap.Containers.Put(itrKey, newC)
itrKey, itrCType, itrN, itrLen, itrPointer, itrErr = itr.Next()
}
if currentBitmap != nil {
bitmaps = append(bitmaps, currentBitmap)
shards = append(shards, currentShard)
}
// we don't support ops logs for this
return bitmaps, shards
}
// BitmapsToRoaring renders a series of non-overlapping bitmaps as a
// unified roaring file.
func BitmapsToRoaring(bitmaps []*Bitmap) []byte {
count := int64(0)
size := int64(0)
for i, bm := range bitmaps {
c, s := bm.roaringSize()
// skip this bitmap during the next pass, since it's empty
if c == 0 {
bitmaps[i] = nil
continue
}
count += c
size += s
}
if count == 0 {
return nil
}
// we have count headers, which need 12 bytes, plus a magic number,
// plus offsets (4 bytes per container), plus size bytes of data to
// write.
out := make([]byte, headerBaseSize+(12*count)+(4*count)+size)
binary.LittleEndian.PutUint16(out[0:2], uint16(MagicNumber))
out[3] = byte(storageVersion)
binary.LittleEndian.PutUint32(out[4:8], uint32(count))
headerEnd := 8 + (12 * count)
offsetEnd := headerEnd + (4 * count)
headers := out[8:headerEnd]
offsets := out[headerEnd:offsetEnd]
data := out[offsetEnd:]
headerOffset := 0
offsetOffset := 0
dataOffset := 0
prevKey := uint64(0)
for _, bm := range bitmaps {
if bm == nil {
continue
}
citer, _ := bm.Containers.Iterator(0)
for citer.Next() {
k, c := citer.Value()
n := c.N()
if n == 0 {
continue
}
if roaringParanoia {
if k < prevKey {
panic("unsorted keys in multiple-bitmap roaring conversion")
}
}
// place header at header offset, and data at data
// offset
header := headers[headerOffset : headerOffset+12]
offset := offsets[offsetOffset : offsetOffset+4]
headerOffset += 12
offsetOffset += 4
binary.LittleEndian.PutUint64(header[0:8], k)
binary.LittleEndian.PutUint16(header[8:10], uint16(c.typeID))
binary.LittleEndian.PutUint16(header[10:12], uint16(n-1))
binary.LittleEndian.PutUint32(offset[0:4], uint32(dataOffset+int(offsetEnd)))
nextData := data[dataOffset:]
switch c.typeID { // TODO: make this work on big endian machines
case ContainerArray:
dataOffset += 2 * copy((*[1 << 16]uint16)(unsafe.Pointer(&nextData[0]))[:c.n:c.n], c.array())
case ContainerBitmap:
copy((*[1024]uint64)(unsafe.Pointer(&nextData[0]))[:], c.bitmap())
dataOffset += 8192
case ContainerRun:
binary.LittleEndian.PutUint16(nextData[0:2], uint16(c.len))
dataOffset += 2
dataOffset += 4 * copy((*[1 << 15]Interval16)(unsafe.Pointer(&nextData[2]))[:c.len:c.len], c.runs())
}
}
}
return out
}
// roaringSize yields the count of non-empty containers, and the size
// of the storage *only* -- not the headers.
func (b *Bitmap) roaringSize() (int64, int64) {
count := int64(0)
size := int64(0)
citer, _ := b.Containers.Iterator(0)
for citer.Next() {
_, c := citer.Value()
if c.N() == 0 {
continue
}
count++
switch c.typeID {
case ContainerArray:
size += 2 * int64(c.N())
case ContainerBitmap:
size += 8192
case ContainerRun:
// 2 bytes for the count of runs, plus 4 bytes per run
size += 2 + (4 * int64(c.len))
}
}
return count, size
}
// Info returns stats for the bitmap.
func (b *Bitmap) Info(includeContainers bool) BitmapInfo {
info := BitmapInfo{
OpN: b.opN,
Ops: b.ops,
ContainerCount: b.Containers.Size(),
}
if includeContainers {
info.Containers = make([]ContainerInfo, 0, info.ContainerCount)
}
citer, _ := b.Containers.Iterator(0)
for citer.Next() {
k, c := citer.Value()
ci := c.info()
ci.Key = k
info.BitCount += uint64(c.N())
if includeContainers {
info.Containers = append(info.Containers, ci)
}
}
return info
}
// Check performs a consistency check on the bitmap. Returns nil if consistent.
func (b *Bitmap) Check() error {
var a ErrorList
// Check each container.
citer, _ := b.Containers.Iterator(0)
for citer.Next() {
k, c := citer.Value()
if err := c.check(); err != nil {
a.AppendWithPrefix(err, fmt.Sprintf("%d/", k))
}
}
if len(a) == 0 {
return nil
}
return a
}
// Flip performs a logical negate of the bits in the range [start,end].
func (b *Bitmap) Flip(start, end uint64) *Bitmap {
if roaringSentinel {
if start > end {
panic(fmt.Sprintf("flipping in range but %v > %v", start, end))
}
}
result := NewBitmap()
itr := b.Iterator()
v, eof := itr.Next()
//copy over previous bits.
for v < start && !eof {
result.DirectAdd(v)
v, eof = itr.Next()
}
//flip bits in range .
for i := start; i <= end; i++ {
if eof {
result.DirectAdd(i)
} else if v == i {
v, eof = itr.Next()
} else {
result.DirectAdd(i)
}
}
//add remaining.
for !eof {
result.DirectAdd(v)
v, eof = itr.Next()
}
return result
}
// BitmapInfo represents a point-in-time snapshot of bitmap stats.
type BitmapInfo struct {
OpN int
Ops int
OpDetails []OpInfo `json:"OpDetails,omitempty"`
BitCount uint64
ContainerCount int
Containers []ContainerInfo `json:"Containers,omitempty"` // The containers found in the bitmap originally
OpContainers []ContainerInfo `json:"OpContainers,omitempty"` // The containers resulting from ops log changes.
From, To uintptr // if set, indicates the address range used when unpacking
}
// Iterator represents an iterator over a Bitmap.
type Iterator struct {
bitmap *Bitmap
citer ContainerIterator
key uint64
c *Container
j, k int32 // i: container; j: array index, bit index, or run index; k: offset within the run
}
// This exists because we used to support a backend which needed it, and I
// don't want to re-experience the joy of figuring out where close calls are needed.
func (itr *Iterator) Close() {}
// Seek moves to the first value equal to or greater than `seek`.
func (itr *Iterator) Seek(seek uint64) {
// k should always be -1 unless we're seeking into a run container. Then the
// "if c.isRun" section will take care of it.
itr.k = -1
// Move to the correct container.
itr.citer, _ = itr.bitmap.Containers.Iterator(highbits(seek))
if !itr.citer.Next() {
itr.c = nil
return // eof
}
itr.key, itr.c = itr.citer.Value()
if roaringParanoia {
if itr.c == nil {
panic("seeking iterator got a nil container when Next() was true")
}
}
// Move to the correct value index inside the container.
lb, hb := lowbits(seek), highbits(seek)
if itr.c.isArray() {
// Seek is smaller than min(itr.c).
if itr.key > hb {
itr.j = -1
return
}
// Find index in the container.
itr.j = search32(itr.c.array(), lb)
if itr.j < 0 {
itr.j = -itr.j - 1
}
if itr.j < int32(len(itr.c.array())) {
itr.j--
return
}
// If it's at the end of the container then move to the next one.
if !itr.citer.Next() {
itr.c = nil
return
}
itr.key, itr.c = itr.citer.Value()
itr.j = -1
return
}
if itr.c.isRun() {
// Seek is smaller than min(itr.c).
if itr.key > hb {
itr.j = 0
itr.k = -1
return
}
j, contains := BinSearchRuns(lb, itr.c.runs())
if contains {
itr.j = j
itr.k = int32(lb) - int32(itr.c.runs()[j].Start) - 1
return
}
// If seek is larger than all elements, return.
if j >= int32(len(itr.c.runs())) {
if !itr.citer.Next() {
itr.c = nil
return
}
itr.key, itr.c = itr.citer.Value()
itr.j = -1
return
}
// Set iterator to next value in the Bitmap.
itr.j = j
itr.k = -1
return
}
// If it's a bitmap container then move to index before the value.
if itr.key > hb {
itr.j = -1
return
}
itr.j = int32(lb) - 1
}
// Next returns the next value in the bitmap.
// Returns eof as true if there are no values left in the iterator.
func (itr *Iterator) Next() (v uint64, eof bool) {
if itr.c == nil {
return 0, true
}
// Iterate over containers until we find the next value or EOF.
for {
if itr.c.isArray() {
if itr.j >= itr.c.N()-1 {
// Reached end of array, move to the next container.
if !itr.citer.Next() {
itr.c = nil
return 0, true
}
itr.key, itr.c = itr.citer.Value()
itr.j = -1
continue
}
itr.j++
return itr.peek(), false
}
if itr.c.isRun() {
// Because itr.j for an array container defaults to -1
// but defaults to 0 for a run container, we need to
// standardize on treating -1 as our default value for itr.j.
// Note that this is easier than changing the default to 0
// because the array logic uses the negative number space
// to represent offsets to an array position that isn't filled
// (-1 being the first empty space in an array, or 0).
if itr.j == -1 {
itr.j++
}
// If the container is empty, move to the next container.
if len(itr.c.runs()) == 0 {
if !itr.citer.Next() {
itr.c = nil
return 0, true
}
itr.key, itr.c = itr.citer.Value()
itr.j = -1
continue
}
r := itr.c.runs()[itr.j]
runLength := int32(r.Last - r.Start)
if itr.k >= runLength {
// Reached end of run, move to the next run.
itr.j, itr.k = itr.j+1, -1
}
if itr.j >= int32(len(itr.c.runs())) {
// Reached end of runs, move to the next container.
if !itr.citer.Next() {
itr.c = nil
return 0, true
}
itr.key, itr.c = itr.citer.Value()
itr.j = -1
continue
}
itr.k++
return itr.peek(), false
}
// Move to the next possible index in the bitmap container.
itr.j++
// Find first non-zero bit in current bitmap, if possible.
hb := itr.j >> 6
if hb >= int32(len(itr.c.bitmap())) {
if !itr.citer.Next() {
itr.c = nil
return 0, true
}
itr.key, itr.c = itr.citer.Value()
itr.j = -1
continue
}
lb := itr.c.bitmap()[hb] >> (uint(itr.j) % 64)
if lb != 0 {
itr.j = itr.j + int32(trailingZeroN(lb))
return itr.peek(), false
}
// Otherwise iterate through remaining bitmaps to find next bit.
for hb++; hb < int32(len(itr.c.bitmap())); hb++ {
if itr.c.bitmap()[hb] != 0 {
itr.j = hb<<6 + int32(trailingZeroN(itr.c.bitmap()[hb]))
return itr.peek(), false
}
}
// If no bits found then move to the next container.
if !itr.citer.Next() {
itr.c = nil
return 0, true
}
itr.key, itr.c = itr.citer.Value()
itr.j = -1
}
}
// peek returns the current value.
func (itr *Iterator) peek() uint64 {
if itr.c == nil {
return 0
}
if itr.c.isArray() {
return itr.key<<16 | uint64(itr.c.array()[itr.j])
}
if itr.c.isRun() {
return itr.key<<16 | uint64(itr.c.runs()[itr.j].Start+uint16(itr.k))
}
return itr.key<<16 | uint64(itr.j)
}
// ArrayMaxSize represents the maximum size of array containers.
const ArrayMaxSize = 4096
// runMaxSize represents the maximum size of run length encoded containers.
const runMaxSize = 2048
type Interval16 struct {
Start uint16
Last uint16
}
// runlen returns the count of integers in the interval.
func (iv Interval16) runlen() int32 {
return 1 + int32(iv.Last-iv.Start)
}
// count counts all bits in the container.
func (c *Container) count() (n int32) {
return c.countRange(0, MaxContainerVal+1)
}
// countRange counts the number of bits set between [start, end).
func (c *Container) countRange(start, end int32) (n int32) {
if roaringParanoia {
if start > end {
panic(fmt.Sprintf("counting in range but %v > %v", start, end))
}
}
if c == nil {
return 0
}
if c.isArray() {
return ArrayCountRange(c.array(), start, end)
} else if c.isRun() {
return RunCountRange(c.runs(), start, end)
}
return BitmapCountRange(c.bitmap(), start, end)
}
func ArrayCountRange(array []uint16, start, end int32) (n int32) {
if roaringParanoia {
if start > end {
panic(fmt.Sprintf("counting in range but %v > %v", start, end))
}
}
i := int32(sort.Search(len(array), func(i int) bool { return int32(array[i]) >= start }))
for ; i < int32(len(array)); i++ {
v := int32(array[i])
if v >= end {
break
}
n++
}
return n
}
// BitmapCountRange counts bits set in [start,end).
func BitmapCountRange(bitmap []uint64, start, end int32) int32 {
if roaringParanoia {
if start > end {
panic(fmt.Sprintf("counting in range but %v > %v", start, end))
}
}
var n uint64
i, j := start/64, end/64
// Special case when start and end fall in the same word.
if i == j {
offi, offj := uint(start%64), uint(64-end%64)
n += popcount((bitmap[i] >> offi) << (offj + offi))
return int32(n)
}
// Count partial starting word.
if off := uint(start) % 64; off != 0 {
n += popcount(bitmap[i] >> off)
i++
}
// Count words in between.
for ; i < j; i++ {
n += popcount(bitmap[i])
}
// Count partial ending word.
if j < int32(len(bitmap)) {
off := 64 - (uint(end) % 64)
n += popcount(bitmap[j] << off)
}
return int32(n)
}
func callbackBits(w uint64, base uint16, fn func(uint16)) {
for w != 0 {
trail := uint16(bits.TrailingZeros64(w))
fn(base + trail)
base += trail + 1
w >>= trail + 1
}
}
// bitmapCallbackRange calls the provided function for every bit set in
// bitmap in the range [start,end).
func bitmapCallbackRange(bitmap []uint64, start, end int32, fn func(uint16)) {
if roaringParanoia {
if start > end {
panic(fmt.Sprintf("counting in range but %v > %v", start, end))
}
}
i, j := start/64, end/64
// Special case when start and end fall in the same word.
if i == j {
// So, we want to know the offsets. For instance, if start and end
// are 65 and 69, we might want i=1, offi=1, j=1, offj=5. Then we
// compute masks from offi (masking out 0x1, or (1<<offi)-1), and
// offj (masking out everything *but* (1<<offj)-1).
//
// But we can also use "x >> offi << offi" to trim the lowest offi
// bits, and "x << (64-offj) >> (64-offj)" to trim all but the
// lowest offj bits.
//
// We can then simplify slightly further: we use the inverted value
// as offj, and compute (w << offi) >> (offi + offj) << offi.
//
// But wait, you ask. What if offi+offj is too large! Well, then
// start and end were in the wrong order. We have 0 <= i <= j < 64.
// If x+i > 64, then x > (64-i). Thus, if (64-j)+i > 64, it
// follows that (64-j) > (64-i). So they'd have been in the wrong order.
// In which case, we correctly yield a value of (0 << offi), or 0,
// because nothing is between them.
offi, offj := uint(start%64), uint(64-(end%64))
w := (bitmap[i] << offj) >> (offi + offj) << offi
if w != 0 {
callbackBits(w, uint16(i)*64, fn)
}
return
}
// Count partial starting word.
if off := uint(start) % 64; off != 0 {
w := (bitmap[i] >> off) << off
if w != 0 {
callbackBits(w, (uint16(i) * 64), fn)
}
i++
}
// Count words in between.
for ; i < j; i++ {
if bitmap[i] != 0 {
callbackBits(bitmap[i], uint16(i)*64, fn)
}
}
// Count partial ending word.
if j < int32(len(bitmap)) {
off := 64 - (uint(end) % 64)
w := (bitmap[j] << off) >> off
if w != 0 {
callbackBits(w, uint16(j)*64, fn)
}
}
}
// RunCountRange returns the ranged bit count for RLE pairs.
func RunCountRange(runs []Interval16, start, end int32) (n int32) {
if roaringParanoia {
if start > end {
panic(fmt.Sprintf("counting in range but %v > %v", start, end))
}
}
for _, iv := range runs {
// iv is before range
if int32(iv.Last) < start {
continue
}
// iv is after range
if end < int32(iv.Start) {
break
}
// iv is superset of range
if int32(iv.Start) <= start && int32(iv.Last) >= end {
return end - start
}
// iv is subset of range
if int32(iv.Start) >= start && int32(iv.Last) <= end {
n += iv.runlen()
}
// iv overlaps beginning of range without being a subset
if int32(iv.Start) < start && int32(iv.Last) < end {
n += int32(iv.Last) - start + 1
}
// iv overlaps end of range without being a subset
if int32(iv.Start) > start && int32(iv.Last) >= end {
n += end - int32(iv.Start)
}
}
return n
}
// add adds a value to the container.
func (c *Container) add(v uint16) (newC *Container, added bool) {
if c == nil {
return NewContainerArray([]uint16{v}), true
}
if c.isArray() {
return c.arrayAdd(v)
} else if c.isRun() {
return c.runAdd(v)
} else {
return c.bitmapAdd(v)
}
}
func (c *Container) arrayAdd(v uint16) (*Container, bool) {
// Optimize appending to the end of an array container.
array := c.array()
if c.N() > 0 && c.N() < ArrayMaxSize && c.isArray() && array[c.N()-1] < v {
statsHit("arrayAdd/append")
c = c.Thaw()
array = append(c.array(), v)
c.setArray(array)
return c, true
}
// Find index of the integer in the container. Exit if it already exists.
i := search32(array, v)
if i >= 0 {
return c, false
}
// Convert to a bitmap container if too many values are in an array container.
if c.N() >= ArrayMaxSize {
statsHit("arrayAdd/arrayToBitmap")
c = c.arrayToBitmap()
return c.bitmapAdd(v)
}
// Otherwise insert into array.
statsHit("arrayAdd/insert")
c = c.Thaw()
i = -i - 1
array = append(c.array(), 0)
copy(array[i+1:], array[i:])
array[i] = v
c.setArray(array)
return c, true
}
func (c *Container) bitmapAdd(v uint16) (*Container, bool) {
if c == nil {
c = NewContainerBitmapN(nil, 1)
c.bitmap()[v/64] |= (1 << uint64(v%64))
return c, true
}
if c.bitmapContains(v) {
return c, false
}
c = c.Thaw()
c.bitmap()[v/64] |= (1 << uint64(v%64))
c.setN(c.N() + 1)
return c, true
}
func (c *Container) runAdd(v uint16) (*Container, bool) {
runs := c.runs()
if len(runs) == 0 {
c = c.Thaw()
c.setRuns([]Interval16{{Start: v, Last: v}})
c.setN(1)
return c, true
}
i := sort.Search(len(runs),
func(i int) bool { return runs[i].Last >= v })
if i == len(runs) {
i--
}
iv := runs[i]
if v >= iv.Start && iv.Last >= v {
return c, false
}
c = c.Thaw()
runs = c.runs()
if iv.Last < v {
if iv.Last == v-1 {
runs[i].Last++
} else {
runs = append(runs, Interval16{Start: v, Last: v})
}
} else if v+1 == iv.Start {
// combining two intervals
if i > 0 && runs[i-1].Last == v-1 {
runs[i-1].Last = iv.Last
runs = append(runs[:i], runs[i+1:]...)
c.setRuns(runs)
c.setN(c.N() + 1)
return c, true
}
// just before an interval
runs[i].Start--
} else if i > 0 && v-1 == runs[i-1].Last {
// just after an interval
runs[i-1].Last++
} else {
// alone
newIv := Interval16{Start: v, Last: v}
runs = append(runs[:i], append([]Interval16{newIv}, runs[i:]...)...)
}
c.setRuns(runs)
c.setN(c.N() + 1)
return c, true
}
// Contains returns true if v is in the container.
func (c *Container) Contains(v uint16) bool {
if c == nil {
return false
}
if c.isArray() {
return c.arrayContains(v)
} else if c.isRun() {
return c.runContains(v)
} else {
return c.bitmapContains(v)
}
}
func (c *Container) bitmapCountRuns() (r int32) {
return bitmapCountRuns(c.bitmap())
}
func bitmapCountRuns(bitmap []uint64) (r int32) {
for i := 0; i < 1023; i++ {
v, v1 := bitmap[i], bitmap[i+1]
r = r + int32(popcount((v<<1)&^v)+((v>>63)&^v1))
}
vl := bitmap[len(bitmap)-1]
r = r + int32(popcount((vl<<1)&^vl)+vl>>63)
return r
}
func arrayCountRuns(array []uint16) (r int32) {
prev := int32(-2)
for _, v := range array {
if prev+1 != int32(v) {
r++
}
prev = int32(v)
}
return r
}
func (c *Container) arrayCountRuns() (r int32) {
return arrayCountRuns(c.array())
}
func (c *Container) countRuns() (r int32) {
if c.isArray() {
return c.arrayCountRuns()
} else if c.isBitmap() {
return c.bitmapCountRuns()
} else if c.isRun() {
return int32(len(c.runs()))
}
// sure hope this never happens
return 0
}
// optimize converts the container to the type which will take up the least
// amount of space.
func (c *Container) optimize() *Container {
if c.N() == 0 {
statsHit("optimize/empty")
return nil
}
runs := c.countRuns()
var newType byte
if runs <= runMaxSize && runs <= c.N()/2 {
newType = ContainerRun
} else if c.N() < ArrayMaxSize {
newType = ContainerArray
} else {
newType = ContainerBitmap
}
// Then convert accordingly.
if c.isArray() {
if newType == ContainerBitmap {
statsHit("optimize/arrayToBitmap")
c = c.arrayToBitmap()
} else if newType == ContainerRun {
statsHit("optimize/arrayToRun")
c = c.arrayToRun(runs)
} else {
statsHit("optimize/arrayUnchanged")
}
} else if c.isBitmap() {
if newType == ContainerArray {
statsHit("optimize/bitmapToArray")
c = c.bitmapToArray()
} else if newType == ContainerRun {
statsHit("optimize/bitmapToRun")
c = c.bitmapToRun(runs)
} else {
statsHit("optimize/bitmapUnchanged")
}
} else if c.isRun() {
if newType == ContainerBitmap {
statsHit("optimize/runToBitmap")
c = c.runToBitmap()
} else if newType == ContainerArray {
statsHit("optimize/runToArray")
c = c.runToArray()
} else {
statsHit("optimize/runUnchanged")
}
}
return c
}
// unionInPlace does not necessarily preserve container's N; it's expected
// to be used when running a sequence of unions, after which you should
// call Repair(). (As of this writing, that only matters for bitmaps.)
//
// If called on a frozen container, or a container of the wrong sort,
// it is possible that the returned container will not actually be the
// original container; in-place is a suggestion.
func (c *Container) unionInPlace(other *Container) *Container {
// short-circuit the trivial cases
cN, cOk := c.SafeN()
if cOk {
if cN == MaxContainerVal+1 {
return fullContainer
}
if cN == 0 {
return other.Clone()
}
}
oN, oOk := other.SafeN()
if oOk {
if oN == MaxContainerVal+1 {
return fullContainer
}
if oN == 0 {
return c
}
}
switch c.typ() {
case ContainerBitmap:
switch other.typ() {
case ContainerBitmap:
return unionBitmapBitmapInPlace(c, other)
case ContainerArray:
return unionBitmapArrayInPlace(c, other)
case ContainerRun:
return unionBitmapRunInPlace(c, other)
}
case ContainerArray:
switch other.typ() {
case ContainerBitmap:
c = c.arrayToBitmap()
return unionBitmapBitmapInPlace(c, other)
case ContainerArray:
return unionArrayArrayInPlace(c, other)
case ContainerRun:
c = c.arrayToBitmap()
return unionBitmapRunInPlace(c, other)
}
case ContainerRun:
switch other.typ() {
case ContainerBitmap:
c = c.runToBitmap()
return unionBitmapBitmapInPlace(c, other)
case ContainerArray:
c = c.runToBitmap()
return unionBitmapArrayInPlace(c, other)
case ContainerRun:
return unionRunRunInPlace(c, other)
}
}
panic(fmt.Errorf("invalid union op: unknown types %d/%d", c.typ(), other.typ()))
}
func (c *Container) arrayContains(v uint16) bool {
return search32(c.array(), v) >= 0
}
func (c *Container) bitmapContains(v uint16) bool {
return (c.bitmap()[v/64] & (1 << uint64(v%64))) != 0
}
// BinSearchRuns returns the index of the run containing v, and true, when v is contained;
// or the index of the next run starting after v, and false, when v is not contained.
func BinSearchRuns(v uint16, a []Interval16) (int32, bool) {
i := int32(sort.Search(len(a),
func(i int) bool {
return a[i].Last >= v
}))
if i < int32(len(a)) {
return i, (v >= a[i].Start) && (v <= a[i].Last)
}
return i, false
}
// runContains determines if v is in the container assuming c is a run
// container.
func (c *Container) runContains(v uint16) bool {
_, found := BinSearchRuns(v, c.runs())
return found
}
// remove removes a value from the container.
func (c *Container) remove(v uint16) (newC *Container, removed bool) {
if c == nil {
return nil, false
}
if c.isArray() {
return c.arrayRemove(v)
} else if c.isRun() {
return c.runRemove(v)
} else {
return c.bitmapRemove(v)
}
}
func (c *Container) arrayRemove(v uint16) (*Container, bool) {
array := c.array()
i := search32(array, v)
if i < 0 {
return c, false
}
// removing the last item? we can just return the empty container.
if c.N() == 1 {
return nil, true
}
c = c.Thaw()
array = c.array()
array = append(array[:i], array[i+1:]...)
c.setArray(array)
return c, true
}
func (c *Container) bitmapRemove(v uint16) (*Container, bool) {
if !c.bitmapContains(v) {
return c, false
}
// removing the last item? we can just return the empty container.
if c.N() == 1 {
return nil, true
}
c = c.Thaw()
// Lower count and remove element.
c.bitmap()[v/64] &^= (uint64(1) << uint(v%64))
c.setN(c.N() - 1)
// Convert to array if we go below the threshold.
if c.N() == ArrayMaxSize {
statsHit("bitmapRemove/bitmapToArray")
c = c.bitmapToArray()
}
return c, true
}
// runRemove removes v from a run container, and returns true if v was removed.
func (c *Container) runRemove(v uint16) (*Container, bool) {
runs := c.runs()
i, contains := BinSearchRuns(v, runs)
if !contains {
return c, false
}
// removing the last item? we can just return the empty container.
if c.N() == 1 {
return nil, true
}
c = c.Thaw()
runs = c.runs()
if v == runs[i].Last && v == runs[i].Start {
runs = append(runs[:i], runs[i+1:]...)
} else if v == runs[i].Last {
runs[i].Last--
} else if v == runs[i].Start {
runs[i].Start++
} else if v > runs[i].Start {
last := runs[i].Last
runs[i].Last = v - 1
runs = append(runs, Interval16{})
copy(runs[i+2:], runs[i+1:])
runs[i+1] = Interval16{Start: v + 1, Last: last}
// runs = append(runs[:i+1], append([]interval16{{start: v + 1, last: last}}, runs[i+1:]...)...)
}
c.setN(c.N() - 1)
c.setRuns(runs)
return c, true
}
// max returns the maximum value in the container.
func (c *Container) max() uint16 {
if c == nil || c.N() == 0 {
// probably wrong, but prevents a crash elsewhere
return 0
}
if c.isArray() {
return c.arrayMax()
} else if c.isRun() {
return c.runMax()
} else {
return c.bitmapMax()
}
}
func (c *Container) arrayMax() uint16 {
array := c.array()
return array[len(array)-1]
}
func (c *Container) bitmapMax() uint16 {
// Search bitmap in reverse order.
bitmap := c.bitmap()
for i := len(bitmap); i > 0; i-- {
// If value is zero then skip.
v := bitmap[i-1]
if v != 0 {
r := bits.LeadingZeros64(v)
return uint16((i-1)*64 + 63 - r)
}
}
return 0
}
func (c *Container) runMax() uint16 {
runs := c.runs()
if len(runs) == 0 {
return 0
}
return runs[len(runs)-1].Last
}
// bitmapToArray converts from bitmap format to array format.
func (c *Container) bitmapToArray() *Container {
statsHit("bitmapToArray")
if c == nil {
if roaringParanoia {
panic("nil container for bitmapToArray")
}
return nil
}
// If c is frozen, we'll be making a new array container. Otherwise,
// we'll convert this container.
if c.N() == 0 {
if c.frozen() {
return NewContainerArray(nil)
}
c.setTyp(ContainerArray)
c.setArray(nil)
return c
}
bitmap := c.bitmap()
// FB-1247 adding an extra check just in case c.N proves to be unreliable
// TODO prove this has to be reliable
makeArray := func(bm []uint64, ar []uint16) ([]uint16, bool, int32) {
n := int32(0)
for i, word := range bm {
for word != 0 {
t := word & -word
if roaringParanoia {
if n >= c.N() {
panic("bitmap has more bits set than container.n")
}
}
if n == int32(len(ar)) {
return ar, true, n
}
ar[n] = uint16((i*64 + int(popcount(t-1))))
n++
word ^= t
}
}
return ar, false, n
}
array, fail, n := makeArray(bitmap, make([]uint16, c.N()))
if fail {
// the onlyreason we are here is because N was incorrect
// so we force a recount of N and try again
c.bitmapRepair()
array, fail, n = makeArray(bitmap, make([]uint16, c.N()))
if fail {
//this should not be able to happen under any circumstance
panic("bitmapToArray failure")
}
}
if roaringParanoia {
if n != c.N() {
panic("bitmap has fewer bits set than container.n")
}
}
if c.frozen() {
return NewContainerArray(array)
}
c.setTyp(ContainerArray)
c.setMapped(false)
c.setArray(array)
return c
}
// arrayToBitmap converts from array format to bitmap format.
func (c *Container) arrayToBitmap() (out *Container) {
statsHit("arrayToBitmap")
if roaringParanoia {
defer func() { out.CheckN() }()
}
if c == nil {
if roaringParanoia {
panic("nil container for arrayToBitmap")
}
return nil
}
// return early if empty
if c.N() == 0 {
if c.frozen() {
return NewContainerBitmap(0, nil)
}
c.setTyp(ContainerBitmap)
c.setBitmap(make([]uint64, bitmapN))
return c
}
bitmap := make([]uint64, bitmapN)
for _, v := range c.array() {
bitmap[int(v)/64] |= (uint64(1) << uint(v%64))
}
if c.frozen() {
return NewContainerBitmapN(bitmap, c.N())
}
c.setTyp(ContainerBitmap)
c.setMapped(false)
c.setBitmap(bitmap)
return c
}
// runToBitmap converts from RLE format to bitmap format.
func (c *Container) runToBitmap() (out *Container) {
statsHit("runToBitmap")
if roaringParanoia {
defer func() { c.CheckN() }()
}
if c == nil {
if roaringParanoia {
panic("nil container for runToBitmap")
}
return nil
}
if roaringParanoia {
if c.N() > 65536 {
panic(fmt.Sprintf("runToBitmap: container N %d", c.N()))
}
}
// return early if empty
if c.N() == 0 {
if c.frozen() {
return NewContainerBitmap(0, nil)
}
c.setTyp(ContainerBitmap)
c.setBitmap(make([]uint64, bitmapN))
return c
}
bitmap := make([]uint64, bitmapN)
for _, iv := range c.runs() {
w1, w2 := iv.Start/64, iv.Last/64
b1, b2 := iv.Start&63, iv.Last&63
// a mask for everything under bit X looks like
// (1 << x) - 1. Say b1 is 4; our mask will want
// to have the bottom 4 bits be zero, so we shift
// left 4, getting 10000, then subtract 1, and
// get 01111, which is the mask to *remove*.
m1 := (uint64(1) << b1) - 1
// inclusive mask: same thing, then shift left 1 and
// or in 1. So for 4, we'd get 011111, which is the
// mask to *keep*.
m2 := (((uint64(1) << b2) - 1) << 1) | 1
if w1 == w2 {
// If we only had bit 4 in the range, this would
// end up being 011111 &^ 01111, or 010000.
bitmap[w1] |= (m2 &^ m1)
continue
}
// for w2, the "To" field, we want to set the bottom N
// bits. For w1, the "From" word, we want to set all *but*
// the bottom N bits.
bitmap[w2] |= m2
bitmap[w1] |= ^m1
words := bitmap[w1+1 : w2]
// set every bit between them
for i := range words {
words[i] = ^uint64(0)
}
}
if c.frozen() {
return NewContainerBitmapN(bitmap, c.N())
}
c.setTyp(ContainerBitmap)
c.setMapped(false)
c.setBitmap(bitmap)
return c
}
// bitmapToRun converts from bitmap format to RLE format.
func (c *Container) bitmapToRun(numRuns int32) *Container {
statsHit("bitmapToRun")
if c == nil {
if roaringParanoia {
panic("nil container for bitmapToRun")
}
return nil
}
// return early if empty
if c.N() == 0 {
if c.frozen() {
return NewContainerRun(nil)
}
c.setTyp(ContainerRun)
c.setRuns(nil)
return c
}
bitmap := c.bitmap()
if numRuns == 0 {
numRuns = bitmapCountRuns(bitmap)
}
runs := make([]Interval16, 0, numRuns)
current := bitmap[0]
var i, start, last uint16
for {
// skip while empty
for current == 0 && i < bitmapN-1 {
i++
current = bitmap[i]
}
if current == 0 {
break
}
currentStart := uint16(trailingZeroN(current))
start = 64*i + currentStart
// pad LSBs with 1s
current = current | (current - 1)
// find next 0
for current == maxBitmap && i < bitmapN-1 {
i++
current = bitmap[i]
}
if current == maxBitmap {
// bitmap[1023] == maxBitmap
runs = append(runs, Interval16{start, MaxContainerVal})
break
}
currentLast := uint16(trailingZeroN(^current))
last = 64*i + currentLast
runs = append(runs, Interval16{start, last - 1})
// pad LSBs with 0s
current = current & (current + 1)
}
if c.frozen() {
return NewContainerRunN(runs, c.N())
}
c.setTyp(ContainerRun)
c.setRuns(runs)
c.setMapped(false)
return c
}
// arrayToRun converts from array format to RLE format.
func (c *Container) arrayToRun(numRuns int32) *Container {
statsHit("arrayToRun")
if c == nil {
if roaringParanoia {
panic("nil container for arrayToRun")
}
return nil
}
// return early if empty
if c.N() == 0 {
if c.frozen() {
return NewContainerRun(nil)
}
c.setTyp(ContainerRun)
c.setRuns(nil)
return c
}
array := c.array()
if numRuns == 0 {
numRuns = arrayCountRuns(array)
}
runs := make([]Interval16, 0, numRuns)
start := array[0]
for i, v := range array[1:] {
if v-array[i] > 1 {
// if current-previous > 1, one run ends and another begins
runs = append(runs, Interval16{start, array[i]})
start = v
}
}
// append final run
runs = append(runs, Interval16{start, array[c.N()-1]})
if c.frozen() {
return NewContainerRunN(runs, c.N())
}
c.setTyp(ContainerRun)
c.setMapped(false)
c.setRuns(runs)
return c
}
// runToArray converts from RLE format to array format.
func (c *Container) runToArray() *Container {
statsHit("runToArray")
if c == nil {
if roaringParanoia {
panic("nil container for runToArray")
}
return nil
}
// return early if empty
if c.N() == 0 {
if c.frozen() {
return NewContainerArray(nil)
}
c.setTyp(ContainerArray)
c.setArray(nil)
return c
}
runs := c.runs()
array := make([]uint16, c.N())
n := int32(0)
for _, r := range runs {
for v := int(r.Start); v <= int(r.Last); v++ {
array[n] = uint16(v)
n++
}
}
if roaringParanoia {
if n != c.N() {
panic("run has fewer bits set than container.n")
}
}
if c.frozen() {
return NewContainerArray(array)
}
c.setTyp(ContainerArray)
c.setMapped(false)
c.setArray(array)
return c
}
// Clone returns a copy of c.
func (c *Container) Clone() (out *Container) {
if roaringParanoia {
defer func() { out.CheckN() }()
}
statsHit("Container/Clone")
if c == nil {
return nil
}
switch c.typ() {
case ContainerArray:
statsHit("Container/Clone/Array")
out = NewContainerArrayCopy(c.array())
case ContainerBitmap:
statsHit("Container/Clone/Bitmap")
other := NewContainerBitmapN(nil, 0)
copy(other.bitmap(), c.bitmap())
other.n = c.n
out = other
case ContainerRun:
statsHit("Container/Clone/Run")
out = NewContainerRunCopy(c.runs())
default:
panic(fmt.Sprintf("cloning a container of unknown type %d", c.typ()))
}
// this should probably never happen
if roaringParanoia {
if out.N() != out.count() {
panic("cloned container has wrong n")
}
}
return out
}
// WriteTo writes c to w.
func (c *Container) WriteTo(w io.Writer) (n int64, err error) {
if c == nil {
return 0, nil
}
if c.isArray() {
return c.arrayWriteTo(w)
} else if c.isRun() {
return c.runWriteTo(w)
} else {
return c.bitmapWriteTo(w)
}
}
func (c *Container) arrayWriteTo(w io.Writer) (n int64, err error) {
statsHit("Container/arrayWriteTo")
array := c.array()
if len(array) == 0 {
return 0, nil
}
// Verify all elements are valid.
// TODO: instead of commenting this out, we need to make it a configuration option
// for _, v := range c.array {
// assert(lowbits(uint64(v)) == v, "cannot write array value out of range: %d", v)
//}
// Write sizeof(uint16) * cardinality bytes.
nn, err := w.Write((*[0xFFFFFFF]byte)(unsafe.Pointer(&array[0]))[: 2*c.N() : 2*c.N()])
return int64(nn), err
}
func (c *Container) bitmapWriteTo(w io.Writer) (n int64, err error) {
statsHit("Container/bitmapWriteTo")
bitmap := c.bitmap()
// Write sizeof(uint64) * bitmapN bytes.
nn, err := w.Write((*[0xFFFFFFF]byte)(unsafe.Pointer(&bitmap[0]))[:(8 * bitmapN):(8 * bitmapN)])
return int64(nn), err
}
func (c *Container) runWriteTo(w io.Writer) (n int64, err error) {
statsHit("Container/runWriteTo")
runs := c.runs()
if len(runs) == 0 {
return 0, nil
}
var byte2 [2]byte
binary.LittleEndian.PutUint16(byte2[:], uint16(len(runs)))
_, err = w.Write(byte2[:])
if err != nil {
return 0, err
}
nn, err := w.Write((*[0xFFFFFFF]byte)(unsafe.Pointer(&runs[0]))[: interval16Size*len(runs) : interval16Size*len(runs)])
return int64(runCountHeaderSize + nn), err
}
// size returns the encoded size of the container, in bytes.
func (c *Container) size() int {
if c.isArray() {
return len(c.array()) * 2 // sizeof(uint16)
} else if c.isRun() {
return len(c.runs())*interval16Size + runCountHeaderSize
} else {
return len(c.bitmap()) * 8 // sizeof(uint64)
}
}
// info returns the current stats about the container.
func (c *Container) info() ContainerInfo {
info := ContainerInfo{N: c.N(), Mapped: c.Mapped()}
if c == nil {
info.Type = "nil"
info.Alloc = 0
return info
}
info.Flags = c.flags.String()
if c.isArray() {
info.Type = "array"
info.Alloc = len(c.array()) * 2 // sizeof(uint16)
} else if c.isRun() {
info.Type = "run"
info.Alloc = len(c.runs())*interval16Size + runCountHeaderSize
} else {
info.Type = "bitmap"
info.Alloc = len(c.bitmap()) * 8 // sizeof(uint64)
}
info.Pointer = uintptr(unsafe.Pointer(c.pointer))
return info
}
// check performs a consistency check on the container.
func (c *Container) check() error {
var a ErrorList
if c == nil {
return nil
}
if c.isArray() {
array := c.array()
if int32(len(array)) != c.N() {
a.Append(fmt.Errorf("array count mismatch: count=%d, n=%d", len(array), c.N()))
}
} else if c.isRun() {
n := RunCountRange(c.runs(), 0, MaxContainerVal+1)
if n != c.N() {
a.Append(fmt.Errorf("run count mismatch: count=%d, n=%d", n, c.N()))
}
} else if c.isBitmap() {
if n := BitmapCountRange(c.bitmap(), 0, MaxContainerVal+1); n != c.N() {
a.Append(fmt.Errorf("bitmap count mismatch: count=%d, n=%d", n, c.N()))
}
} else {
a.Append(fmt.Errorf("empty container"))
if c.N() != 0 {
a.Append(fmt.Errorf("empty container with nonzero count: n=%d", c.N()))
}
}
if a == nil {
return nil
}
return a
}
// Repair repairs the cardinality of c if it has been corrupted by
// optimized operations.
func (c *Container) Repair() {
// a frozen container can't have had n or contents changed, so we
// don't need to recount it.
if c.frozen() {
return
}
if c.isBitmap() {
c.bitmapRepair()
c.setDirty(false)
}
}
func (c *Container) bitmapRepair() {
n := int32(0)
// Manually unroll loop to make it a little faster.
// TODO(rartoul): Can probably make this a few x faster using
// SIMD instructions.
bitmap := c.bitmap()[:bitmapN]
for i := 0; i <= bitmapN-4; i += 4 {
n += int32(popcount(bitmap[i]))
n += int32(popcount(bitmap[i+1]))
n += int32(popcount(bitmap[i+2]))
n += int32(popcount(bitmap[i+3]))
}
c.setN(n)
}
// ContainerInfo represents a point-in-time snapshot of container stats.
type ContainerInfo struct {
Key uint64 // container key
Type string // container type (array, bitmap, or run)
Flags string // flag state
N int32 // number of bits
Alloc int // memory used
Pointer uintptr // address
Mapped bool // whether this container thinks it is mmapped
}
// flip returns a new container containing the inverse of all
// bits in a.
func flip(a *Container) *Container { // nolint: deadcode
if a.isArray() {
return flipArray(a)
} else if a.isRun() {
return flipRun(a)
} else {
return flipBitmap(a)
}
}
func flipArray(b *Container) *Container {
statsHit("flipArray")
// TODO: actually implement this
x := b.Clone()
x = x.arrayToBitmap()
return flipBitmap(x)
}
func flipBitmap(b *Container) *Container {
statsHit("flipBitmap")
other := NewContainerBitmapN(nil, 0)
bitmap := b.bitmap()
otherBitmap := other.bitmap()
for i, word := range bitmap {
otherBitmap[i] = ^word
}
other.setN(other.count())
return other
}
func flipRun(b *Container) *Container {
statsHit("flipRun")
// TODO: actually implement this
x := b.Clone()
x = x.runToBitmap()
return flipBitmap(x)
}
// IntersectionAny checks whether two containers have any overlap without
// counting past the first bit found.
func IntersectionAny(a, b *Container) bool {
return intersectionAny(a, b)
}
func intersectionAny(a, b *Container) bool {
an := a.N()
if an == 0 {
return false
}
bn := b.N()
if bn == 0 {
return false
}
if an+bn > MaxContainerVal+1 {
return true
}
if a.isArray() {
if b.isArray() {
return intersectionAnyArrayArray(a, b)
} else if b.isRun() {
return intersectionAnyArrayRun(a, b)
} else {
return intersectionAnyArrayBitmap(a, b)
}
} else if a.isRun() {
if b.isArray() {
return intersectionAnyArrayRun(b, a)
} else if b.isRun() {
return intersectionAnyRunRun(a, b)
} else {
return intersectionAnyRunBitmap(a, b)
}
} else {
if b.isArray() {
return intersectionAnyArrayBitmap(b, a)
} else if b.isRun() {
return intersectionAnyRunBitmap(b, a)
} else {
return intersectionAnyBitmapBitmap(a, b)
}
}
}
func intersectionAnyArrayArray(a, b *Container) bool {
ca, cb := a.array(), b.array()
nb := len(cb)
j := 0
for _, va := range ca {
for cb[j] < va {
j++
if j >= nb {
return false
}
}
if cb[j] == va {
return true
}
}
return false
}
func intersectionAnyArrayRun(a, b *Container) bool {
array, runs := a.array(), b.runs()
na, nb := len(array), len(runs)
for i, j := 0, 0; i < na && j < nb; {
va, vb := array[i], runs[j]
if va < vb.Start {
i++
} else if va >= vb.Start && va <= vb.Last {
return true
} else if va > vb.Last {
j++
}
}
return false
}
func intersectionAnyArrayBitmap(a, b *Container) bool {
bitmap := b.bitmap()[:1024]
for _, val := range a.array() {
i := int(val >> 6)
off := val % 64
if (bitmap[i]>>off)&1 != 0 {
return true
}
}
return false
}
func intersectionAnyRunRun(a, b *Container) bool {
ra, rb := a.runs(), b.runs()
na, nb := len(ra), len(rb)
for i, j := 0, 0; i < na && j < nb; {
va, vb := ra[i], rb[j]
if va.Last < vb.Start {
// |--va--| |--vb--|
i++
} else if va.Start > vb.Last {
// |--vb--| |--va--|
j++
} else {
// va.Last >= vb.Start, and va.Start <= vb.Last,
// means there must be overlap
return true
}
}
return false
}
func intersectionAnyRunBitmap(a, b *Container) bool {
bb := b.bitmap()[:1024]
runs := a.runs()
for _, r := range runs {
if r.Start/64 == r.Last/64 {
mask := (^uint64(0) << (r.Start % 64)) &^
(^uint64(0) << ((r.Last % 64) + 1))
if mask&bb[r.Start/64] != 0 {
return true
}
continue
}
firstWord, lastWord := r.Start/64, r.Last/64
for i := firstWord + 1; i < lastWord; i++ {
if bb[i] != 0 {
return true
}
}
firstMask := ^uint64(0) << (r.Start % 64)
lastMask := ^(^uint64(0) << ((r.Last % 64) + 1))
if (firstMask&bb[firstWord])|(lastMask&bb[lastWord]) != 0 {
return true
}
}
return false
}
func intersectionAnyBitmapBitmap(a, b *Container) bool {
ba, bb := a.bitmap()[:1024], b.bitmap()[:1024]
for i, v := range ba {
if bb[i]&v != 0 {
return true
}
}
return false
}
func ContainerCallback(a *Container, fn func(uint16)) {
if a.N() == 0 {
return
}
switch {
case a.isArray():
values := a.array()
for _, v := range values {
fn(v)
}
case a.isBitmap():
values := a.bitmap()
for i, w := range values {
if w == 0 {
continue
}
callbackBits(w, uint16(i)*64, fn)
}
case a.isRun():
values := a.runs()
for _, r := range values {
for i := int(r.Start); i <= int(r.Last); i++ {
fn(uint16(i))
}
}
}
}
func intersectionCallback(a, b *Container, fn func(uint16)) {
if a.N() == MaxContainerVal+1 {
ContainerCallback(b, fn)
return
}
if b.N() == MaxContainerVal+1 {
ContainerCallback(a, fn)
return
}
if a.N() == 0 || b.N() == 0 {
return
}
if a.isArray() {
if b.isArray() {
intersectionCallbackArrayArray(a, b, fn)
} else if b.isRun() {
intersectionCallbackArrayRun(a, b, fn)
} else {
intersectionCallbackArrayBitmap(a, b, fn)
}
} else if a.isRun() {
if b.isArray() {
intersectionCallbackArrayRun(b, a, fn)
} else if b.isRun() {
intersectionCallbackRunRun(a, b, fn)
} else {
intersectionCallbackBitmapRun(b, a, fn)
}
} else {
if b.isArray() {
intersectionCallbackArrayBitmap(b, a, fn)
} else if b.isRun() {
intersectionCallbackBitmapRun(a, b, fn)
} else {
intersectionCallbackBitmapBitmap(a, b, fn)
}
}
}
func intersectionCount(a, b *Container) int32 {
if a.N() == MaxContainerVal+1 {
return b.N()
}
if b.N() == MaxContainerVal+1 {
return a.N()
}
if a.N() == 0 || b.N() == 0 {
return 0
}
if a.isArray() {
if b.isArray() {
return intersectionCountArrayArray(a, b)
} else if b.isRun() {
return intersectionCountArrayRun(a, b)
} else {
return intersectionCountArrayBitmap(a, b)
}
} else if a.isRun() {
if b.isArray() {
return intersectionCountArrayRun(b, a)
} else if b.isRun() {
return intersectionCountRunRun(a, b)
} else {
return intersectionCountBitmapRun(b, a)
}
} else {
if b.isArray() {
return intersectionCountArrayBitmap(b, a)
} else if b.isRun() {
return intersectionCountBitmapRun(a, b)
} else {
return intersectionCountBitmapBitmap(a, b)
}
}
}
func intersectionCountArrayArray(a, b *Container) (n int32) {
statsHit("intersectionCount/ArrayArray")
ca, cb := a.array(), b.array()
na, nb := len(ca), len(cb)
if na > nb {
ca, cb = cb, ca
na, nb = nb, na //nolint: staticcheck, ineffassign
}
j := 0
for _, va := range ca {
for cb[j] < va {
j++
if j >= nb {
return n
}
}
if cb[j] == va {
n++
}
}
return n
}
func intersectionCountArrayRun(a, b *Container) (n int32) {
statsHit("intersectionCount/ArrayRun")
array, runs := a.array(), b.runs()
na, nb := len(array), len(runs)
for i, j := 0, 0; i < na && j < nb; {
va, vb := array[i], runs[j]
if va < vb.Start {
i++
} else if va >= vb.Start && va <= vb.Last {
i++
n++
} else if va > vb.Last {
j++
}
}
return n
}
func intersectionCountRunRun(a, b *Container) (n int32) {
statsHit("intersectionCount/RunRun")
ra, rb := a.runs(), b.runs()
na, nb := len(ra), len(rb)
for i, j := 0, 0; i < na && j < nb; {
va, vb := ra[i], rb[j]
if va.Last < vb.Start {
// |--va--| |--vb--|
i++
} else if va.Start > vb.Last {
// |--vb--| |--va--|
j++
} else if va.Last > vb.Last && va.Start >= vb.Start {
// |--vb-|-|-va--|
n += 1 + int32(vb.Last-va.Start)
j++
} else if va.Last > vb.Last && va.Start < vb.Start {
// |--va|--vb--|--|
n += 1 + int32(vb.Last-vb.Start)
j++
} else if va.Last <= vb.Last && va.Start >= vb.Start {
// |--vb|--va--|--|
n += 1 + int32(va.Last-va.Start)
i++
} else if va.Last <= vb.Last && va.Start < vb.Start {
// |--va-|-|-vb--|
n += 1 + int32(va.Last-vb.Start)
i++
}
}
return n
}
func intersectionCountBitmapRun(a, b *Container) (n int32) {
statsHit("intersectionCount/BitmapRun")
for _, iv := range b.runs() {
n += BitmapCountRange(a.bitmap(), int32(iv.Start), int32(iv.Last)+1)
}
return n
}
func intersectionCountArrayBitmap(a, b *Container) (n int32) {
statsHit("intersectionCount/ArrayBitmap")
bitmap := b.bitmap()
ln := len(bitmap)
for _, val := range a.array() {
i := int(val >> 6)
if i >= ln {
break
}
off := val % 64
n += int32(bitmap[i]>>off) & 1
}
return n
}
func intersectionCountBitmapBitmap(a, b *Container) (n int32) {
statsHit("intersectionCount/BitmapBitmap")
return int32(popcountAndSlice(a.bitmap(), b.bitmap()))
}
func intersectionCallbackArrayArray(a, b *Container, fn func(uint16)) {
statsHit("intersectionCallback/ArrayArray")
ca, cb := a.array(), b.array()
na, nb := len(ca), len(cb)
if na > nb {
ca, cb = cb, ca
na, nb = nb, na //nolint: staticcheck, ineffassign
}
if (na << 2) < nb {
for _, va := range ca {
if cb[0] < va {
// try to skip ahead a bit faster
for len(cb) > 7 && cb[7] < va {
cb = cb[8:]
}
for len(cb) > 0 && cb[0] < va {
cb = cb[1:]
}
if len(cb) == 0 {
return
}
}
if cb[0] == va {
fn(va)
}
}
return
}
j := 0
for _, va := range ca {
for cb[j] < va {
j++
if j >= nb {
return
}
}
if cb[j] == va {
fn(va)
}
}
}
func intersectionCallbackArrayRun(a, b *Container, fn func(uint16)) {
statsHit("intersectionCallback/ArrayRun")
array, runs := a.array(), b.runs()
na, nb := len(array), len(runs)
for i, j := 0, 0; i < na && j < nb; {
va, vb := array[i], runs[j]
if va > vb.Last {
j++
continue
}
// If we got here, va is either before or in the current run,
// so we're definitely done with this member of the array.
i++
if va >= vb.Start {
fn(va)
}
}
}
func intersectionCallbackRunRun(a, b *Container, fn func(uint16)) {
statsHit("intersectionCallback/RunRun")
ra, rb := a.runs(), b.runs()
na, nb := len(ra), len(rb)
for i, j := 0, 0; i < na && j < nb; {
va, vb := ra[i], rb[j]
if va.Last < vb.Start {
// |--va--| |--vb--|
i++
} else if va.Start > vb.Last {
// |--vb--| |--va--|
j++
} else if va.Last > vb.Last && va.Start >= vb.Start {
// |--vb-|-|-va--|
for z := int(va.Start); z <= int(vb.Last); z++ {
fn(uint16(z))
}
j++
} else if va.Last > vb.Last && va.Start < vb.Start {
// |--va|--vb--|--|
for z := int(vb.Start); z <= int(vb.Last); z++ {
fn(uint16(z))
}
j++
} else if va.Last <= vb.Last && va.Start >= vb.Start {
// |--vb|--va--|--|
for z := int(va.Start); z <= int(va.Last); z++ {
fn(uint16(z))
}
i++
} else if va.Last <= vb.Last && va.Start < vb.Start {
// |--va-|-|-vb--|
for z := int(vb.Start); z <= int(va.Last); z++ {
fn(uint16(z))
}
i++
}
}
}
func intersectionCallbackBitmapRun(a, b *Container, fn func(uint16)) {
statsHit("intersectionCallback/BitmapRun")
for _, iv := range b.runs() {
bitmapCallbackRange(a.bitmap(), int32(iv.Start), int32(iv.Last)+1, fn)
}
}
func intersectionCallbackArrayBitmap(a, b *Container, fn func(uint16)) {
statsHit("intersectionCallback/ArrayBitmap")
bitmap := b.bitmap()
ln := len(bitmap)
for _, val := range a.array() {
i := int(val >> 6)
if i >= ln {
break
}
off := val % 64
if (bitmap[i]>>off)&1 != 0 {
fn(val)
}
}
}
func intersectionCallbackBitmapBitmap(a, b *Container, fn func(uint16)) {
statsHit("intersectionCallback/BitmapBitmap")
ab, bb := a.bitmap(), b.bitmap()
for i := range ab {
w := ab[i] & bb[i]
if w == 0 {
continue
}
base := uint16(i) * 64
callbackBits(w, base, fn)
}
}
func intersect(a, b *Container) (c *Container) {
if roaringParanoia {
defer func() { c.CheckN() }()
}
if a.N() == MaxContainerVal+1 {
return b.Freeze()
}
if b.N() == MaxContainerVal+1 {
return a.Freeze()
}
if a.N() == 0 || b.N() == 0 {
return nil
}
if a.isArray() {
if b.isArray() {
return intersectArrayArray(a, b)
} else if b.isRun() {
return intersectArrayRun(a, b)
} else {
return intersectArrayBitmap(a, b)
}
} else if a.isRun() {
if b.isArray() {
return intersectArrayRun(b, a)
} else if b.isRun() {
return intersectRunRun(a, b)
} else {
return intersectBitmapRun(b, a)
}
} else {
if b.isArray() {
return intersectArrayBitmap(b, a)
} else if b.isRun() {
return intersectBitmapRun(a, b)
} else {
return intersectBitmapBitmap(a, b)
}
}
}
func intersectArrayArray(a, b *Container) *Container {
statsHit("intersect/ArrayArray")
aa, ab := a.array(), b.array()
na, nb := len(aa), len(ab)
output := make([]uint16, 0, na)
for i, j := 0, 0; i < na && j < nb; {
va, vb := aa[i], ab[j]
if va < vb {
i++
} else if va > vb {
j++
} else {
output = append(output, va)
i, j = i+1, j+1
}
}
return NewContainerArray(output)
}
// intersectArrayRun computes the intersect of an array container and a run
// container. The return is always an array container (since it's guaranteed to
// be low-cardinality)
func intersectArrayRun(a, b *Container) *Container {
statsHit("intersect/ArrayRun")
aa, rb := a.array(), b.runs()
na, nb := len(aa), len(rb)
var output []uint16
for i, j := 0, 0; i < na && j < nb; {
va, vb := aa[i], rb[j]
if va < vb.Start {
i++
} else if va > vb.Last {
j++
} else {
output = append(output, va)
i++
}
}
return NewContainerArray(output)
}
// intersectRunRun computes the intersect of two run containers.
func intersectRunRun(a, b *Container) *Container {
statsHit("intersect/RunRun")
output := NewContainerRun(nil)
ra, rb := a.runs(), b.runs()
na, nb := len(ra), len(rb)
n := int32(0)
for i, j := 0, 0; i < na && j < nb; {
va, vb := ra[i], rb[j]
if va.Last < vb.Start {
// |--va--| |--vb--|
i++
} else if vb.Last < va.Start {
// |--vb--| |--va--|
j++
} else if va.Last > vb.Last && va.Start >= vb.Start {
// |--vb-|-|-va--|
n += output.runAppendInterval(Interval16{Start: va.Start, Last: vb.Last})
j++
} else if va.Last > vb.Last && va.Start < vb.Start {
// |--va|--vb--|--|
n += output.runAppendInterval(vb)
j++
} else if va.Last <= vb.Last && va.Start >= vb.Start {
// |--vb|--va--|--|
n += output.runAppendInterval(va)
i++
} else if va.Last <= vb.Last && va.Start < vb.Start {
// |--va-|-|-vb--|
n += output.runAppendInterval(Interval16{Start: vb.Start, Last: va.Last})
i++
}
}
output.setN(n)
runs := output.runs()
if n < ArrayMaxSize && int32(len(runs)) > n/2 {
output = output.runToArray()
} else if len(runs) > runMaxSize {
output = output.runToBitmap()
}
return output
}
// intersectBitmapRun returns an array container if either container's
// cardinality is <= ArrayMaxSize. Otherwise it returns a bitmap container.
func intersectBitmapRun(a, b *Container) *Container {
statsHit("intersect/BitmapRun")
var output *Container
runs := b.runs()
// Intersection will be array-sized for sure if either of the inputs
// is array-sized.
if b.N() <= ArrayMaxSize {
var scratch [ArrayMaxSize]uint16
n := 0
for _, iv := range runs {
for i := int(iv.Start); i <= int(iv.Last); i++ {
if a.bitmapContains(uint16(i)) {
scratch[n] = uint16(i)
n++
}
}
}
// output is array container
array := make([]uint16, n)
copy(array, scratch[:])
output = NewContainerArray(array)
} else {
// right now this iterates through the runs and sets integers in the
// bitmap that are in the runs. alternately, we could zero out ranges in
// the bitmap which are between runs.
output = NewContainerBitmap(0, nil)
bitmap := output.bitmap()
aBitmap := a.bitmap()
n := int32(0)
for j := 0; j < len(runs); j++ {
vb := runs[j]
i := vb.Start >> 6 // index into a
vastart := i << 6
valast := vastart + 63
for valast >= vb.Start && vastart <= vb.Last && i < bitmapN {
if vastart >= vb.Start && valast <= vb.Last { // a within b
bitmap[i] = aBitmap[i]
n += int32(popcount(aBitmap[i]))
} else if vb.Start >= vastart && vb.Last <= valast { // b within a
var mask uint64 = ((1 << (vb.Last - vb.Start + 1)) - 1) << (vb.Start - vastart)
bits := aBitmap[i] & mask
bitmap[i] |= bits
n += int32(popcount(bits))
} else if vastart < vb.Start { // a overlaps front of b
offset := 64 - (1 + valast - vb.Start)
bits := (aBitmap[i] >> offset) << offset
bitmap[i] |= bits
n += int32(popcount(bits))
} else if vb.Start < vastart { // b overlaps front of a
offset := 64 - (1 + vb.Last - vastart)
bits := (aBitmap[i] << offset) >> offset
bitmap[i] |= bits
n += int32(popcount(bits))
}
// update loop vars
i++
vastart = i << 6
valast = vastart + 63
}
}
output.setN(n)
}
return output
}
func intersectArrayBitmap(a, b *Container) *Container {
statsHit("intersect/ArrayBitmap")
array := make([]uint16, 0)
bBitmap := b.bitmap()
for _, va := range a.array() {
bmidx := va / 64
bidx := va % 64
mask := uint64(1) << bidx
b := bBitmap[bmidx]
if b&mask > 0 {
array = append(array, va)
}
}
return NewContainerArray(array)
}
func intersectBitmapBitmap(a, b *Container) *Container {
statsHit("intersect/BitmapBitmap")
// local variables added to prevent BCE checks in loop
// see https://go101.org/article/bounds-check-elimination.html
var (
ab = a.bitmask()
bb = b.bitmask()
ob = [1024]uint64{}
n int32
)
_, _ = &ab[0], &bb[0]
for i := range ob {
ob[i] = ab[i] & bb[i]
n += int32(popcount(ob[i]))
}
output := NewContainerBitmapN(ob[:], n)
return output
}
func union(a, b *Container) (c *Container) {
if roaringParanoia {
defer func() { c.CheckN() }()
}
if a.N() == MaxContainerVal+1 || b.N() == MaxContainerVal+1 {
return fullContainer
}
if a.isArray() {
if b.isArray() {
return unionArrayArray(a, b)
} else if b.isRun() {
return unionArrayRun(a, b)
} else {
return unionArrayBitmap(a, b)
}
} else if a.isRun() {
if b.isArray() {
return unionArrayRun(b, a)
} else if b.isRun() {
return unionRunRun(a, b)
} else {
return unionBitmapRun(b, a)
}
} else {
if b.isArray() {
return unionArrayBitmap(b, a)
} else if b.isRun() {
return unionBitmapRun(a, b)
} else {
return unionBitmapBitmap(a, b)
}
}
}
func Merge(a, b []uint16) {
}
func unionArrayArray(a, b *Container) *Container {
statsHit("union/ArrayArray")
if a.N() == 0 {
return b
}
if b.N() == 0 {
return a
}
s1, s2 := a.array(), b.array()
n1, n2 := len(s1), len(s2)
output := make([]uint16, 0, n1+n2)
i, j := 0, 0
for {
va, vb := s1[i], s2[j]
if va < vb {
output = append(output, va)
i++
} else if va > vb {
output = append(output, vb)
j++
} else {
output = append(output, va)
i++
j++
}
// It's possible we hit the ends at the same time,
// in which case the append will copy 0 items. This
// is cheaper than performing a separate conditional
// check every time...
if j >= n2 {
output = append(output, s1[i:]...)
break
}
if i >= n1 {
output = append(output, s2[j:]...)
break
}
}
// note: len(output) CAN be > 4096
return NewContainerArray(output)
}
// unionArrayArrayInPlace does what it sounds like -- tries to combine
// the two arrays in-place. It does not try to ensure that the result is
// of a good array size, so it could be up to twice that size, temporarily.
func unionArrayArrayInPlace(a, b *Container) *Container {
statsHit("union/ArrayArrayInPlace")
if a.N() == 0 {
if b.N() != 0 {
// for InPlace, we actually want to ensure that
// we update a, as long as it's not frozen.
a = a.Thaw()
// ... but we also want to be sure we don't end up
// copying in a mapped object into our not-mapped
// object.
a.setArrayMaybeCopy(b.array(), b.Mapped())
return a.optimize()
}
return a
}
if b.N() == 0 {
return a
}
s1, s2 := a.array(), b.array()
n1, n2 := len(s1), len(s2)
output := make([]uint16, 0, n1+n2)
i, j := 0, 0
for {
va, vb := s1[i], s2[j]
if va < vb {
output = append(output, va)
i++
} else if va > vb {
output = append(output, vb)
j++
} else {
output = append(output, va)
i++
j++
}
// It's possible we hit the ends at the same time,
// in which case the append will copy 0 items. This
// is cheaper than performing a separate conditional
// check every time...
if j >= n2 {
output = append(output, s1[i:]...)
break
}
if i >= n1 {
output = append(output, s2[j:]...)
break
}
}
// a union can't omit anything that was previously in a, so if
// the output is the same length, nothing changed.
if len(output) != int(a.N()) {
a = a.Thaw()
a.setArray(output)
}
return a.optimize()
}
// unionArrayRun optimistically assumes that the result will be a run container,
// and converts to a bitmap or array container afterwards if necessary.
func unionArrayRun(a, b *Container) *Container {
statsHit("union/ArrayRun")
output := NewContainerRun(nil)
aa, rb := a.array(), b.runs()
na, nb := len(aa), len(rb)
var vb Interval16
var va uint16
n := int32(0)
for i, j := 0, 0; i < na || j < nb; {
if i < na {
va = aa[i]
}
if j < nb {
vb = rb[j]
}
if i < na && (j >= nb || va < vb.Start) {
n += output.runAppendInterval(Interval16{Start: va, Last: va})
i++
} else {
n += output.runAppendInterval(vb)
j++
}
}
output.setN(n)
if n < ArrayMaxSize {
output = output.runToArray()
} else if len(output.runs()) > runMaxSize {
output = output.runToBitmap()
}
return output
}
// runAppendInterval adds the given interval to the run container. It assumes
// that the interval comes at the end of the list of runs, and does not check
// that this is the case. It will not behave correctly if the start of the given
// interval is earlier than the start of the last interval in the list of runs.
// Its return value is the amount by which the cardinality of the container was
// increased.
func (c *Container) runAppendInterval(v Interval16) int32 {
runs := c.runs()
if len(runs) == 0 {
runs = append(runs, v)
c.setRuns(runs)
return int32(v.Last-v.Start) + 1
}
last := runs[len(runs)-1]
if last.Last == MaxContainerVal { //protect against overflow
return 0
}
if last.Last+1 >= v.Start && v.Last > last.Last {
runs[len(runs)-1].Last = v.Last
c.setRuns(runs)
return int32(v.Last - last.Last)
} else if last.Last+1 < v.Start {
runs = append(runs, v)
c.setRuns(runs)
return int32(v.Last-v.Start) + 1
}
return 0
}
func unionRunRun(a, b *Container) *Container {
statsHit("union/RunRun")
ra, rb := a.runs(), b.runs()
na, nb := len(ra), len(rb)
output := NewContainerRun(make([]Interval16, 0, na+nb))
var va, vb Interval16
n := int32(0)
for i, j := 0, 0; i < na || j < nb; {
if i < na {
va = ra[i]
}
if j < nb {
vb = rb[j]
}
if i < na && (j >= nb || va.Start < vb.Start) {
n += output.runAppendInterval(va)
i++
} else {
n += output.runAppendInterval(vb)
j++
}
}
output.setN(n)
if len(output.runs()) > runMaxSize {
output = output.runToBitmap()
}
return output
}
func unionBitmapRun(a, b *Container) *Container {
statsHit("union/BitmapRun")
output := a.Clone()
for _, run := range b.runs() {
output.bitmapSetRange(uint64(run.Start), uint64(run.Last)+1)
}
return output
}
// unions the run b into the bitmap a, mutating a in place. The n value of
// a will need to be repaired after the fact.
func unionBitmapRunInPlace(a, b *Container) *Container {
a = a.Thaw()
a.setDirty(true)
bitmap := a.bitmap()
statsHit("union/BitmapRun")
for _, run := range b.runs() {
bitmapSetRangeIgnoreN(bitmap, uint64(run.Start), uint64(run.Last)+1)
}
return a
}
const maxBitmap = 0xFFFFFFFFFFFFFFFF
// sets all bits in [i, j) (c must be a bitmap container, and bitmap must
// be its bitmap).
func (c *Container) bitmapSetRange(i, j uint64) {
bitmap := c.bitmap()
x := i >> 6
y := (j - 1) >> 6
var X uint64 = maxBitmap << (i % 64)
var Y uint64 = maxBitmap >> (63 - ((j - 1) % 64))
xcnt := popcount(X)
ycnt := popcount(Y)
n := int32(c.N())
if x == y {
n += int32((j - i) - popcount(bitmap[x]&(X&Y)))
bitmap[x] |= (X & Y)
} else {
n += int32(xcnt - popcount(bitmap[x]&X))
bitmap[x] |= X
for i := x + 1; i < y; i++ {
n += int32(64 - popcount(bitmap[i]))
bitmap[i] = maxBitmap
}
n += int32(ycnt - popcount(bitmap[y]&Y))
bitmap[y] |= Y
}
c.setN(n)
}
// sets all bits in [i, j) without updating any corresponding n value.
func bitmapSetRangeIgnoreN(bitmap []uint64, i, j uint64) {
x := i >> 6
y := (j - 1) >> 6
var X uint64 = maxBitmap << (i % 64)
var Y uint64 = maxBitmap >> (63 - ((j - 1) % 64))
if x == y {
bitmap[x] |= (X & Y)
} else {
bitmap[x] |= X
for i := x + 1; i < y; i++ {
bitmap[i] = maxBitmap
}
bitmap[y] |= Y
}
}
// xor's all bits in [i, j) with all true (c must be a bitmap container).
func (c *Container) bitmapXorRange(i, j uint64) {
x := i >> 6
y := (j - 1) >> 6
var X uint64 = maxBitmap << (i % 64)
var Y uint64 = maxBitmap >> (63 - ((j - 1) % 64))
bitmap := c.bitmap()
n := c.N()
if x == y {
cnt := popcount(bitmap[x])
bitmap[x] ^= (X & Y) //// flip
n += int32(popcount(bitmap[x]) - cnt)
} else {
cnt := popcount(bitmap[x])
bitmap[x] ^= X
n += int32(popcount(bitmap[x]) - cnt)
for i := x + 1; i < y; i++ {
cnt = popcount(bitmap[i])
bitmap[i] ^= maxBitmap
n += int32(popcount(bitmap[i]) - cnt)
}
cnt = popcount(bitmap[y])
bitmap[y] ^= Y
n += int32(popcount(bitmap[y]) - cnt)
}
c.setN(n)
}
// zeroes all bits in [i, j) (c must be a bitmap container)
func (c *Container) bitmapZeroRange(i, j uint64) {
x := i >> 6
y := (j - 1) >> 6
var X uint64 = maxBitmap << (i % 64)
var Y uint64 = maxBitmap >> (63 - ((j - 1) % 64))
bitmap := c.bitmap()
n := c.N()
if x == y {
n -= int32(popcount(bitmap[x] & (X & Y)))
bitmap[x] &= ^(X & Y)
} else {
n -= int32(popcount(bitmap[x] & X))
bitmap[x] &= ^X
for i := x + 1; i < y; i++ {
n -= int32(popcount(bitmap[i]))
bitmap[i] = 0
}
n -= int32(popcount(bitmap[y] & Y))
bitmap[y] &= ^Y
}
c.setN(n)
}
func typePair(ct1, ct2 byte) int {
return int((ct1 << 4) | ct2)
}
// compareArrayBitmap actually only verifies that everything in the array
// is in the bitmap. It's used only after comparing the N for the containers,
// so if there's anything in the bitmap that's not in the array, either there's
// something in the array that's not in the bitmap, or we didn't get here.
func compareArrayBitmap(a []uint16, b []uint64) error {
for _, v := range a {
w, bit := b[v>>6], v&63
if w>>bit&1 == 0 {
return fmt.Errorf("value %d missing", v)
}
}
return nil
}
// compareArrayRuns determines whether an array matches a provided
// set of runs. As with compareArrayBitmap, it only verifies presence
// of the array's values in the run collection. the run collection
// can't be empty; if it were, N would have been 0, and we wouldn't
// have gotten here.
func compareArrayRuns(a []uint16, r []Interval16) error {
ri := 0
ru := r[ri]
ri++
for _, v := range a {
if v < ru.Start {
return fmt.Errorf("value %d missing", v)
}
if v > ru.Last {
if ri >= len(r) {
return fmt.Errorf("value %d missing", v)
}
ru = r[ri]
ri++
// if they're identical, the array value must be
// the start of the next run.
if v != ru.Start {
return fmt.Errorf("value %d missing", v)
}
}
}
return nil
}
// compareArrayArray reports whether everything in a1 is equal to everything
// in a2.
func compareArrayArray(a1, a2 []uint16) error {
if len(a1) != len(a2) {
return fmt.Errorf("unexpected length mismatch, %d vs %d", len(a1), len(a2))
}
for i := range a1 {
if a1[i] != a2[i] {
return fmt.Errorf("item %d: %d vs %d", i, a1[i], a2[i])
}
}
return nil
}
// BitwiseCompare reports whether two containers are equal. It returns
// an error describing any difference it finds. This is mostly intended
// for use in tests that expect equality.
func (c *Container) BitwiseCompare(c2 *Container) error {
cn, c2n := c.N(), c2.N()
if cn != c2n {
return fmt.Errorf("containers are different lengths (%d vs %d)", cn, c2n)
}
if cn == 0 {
return nil
}
switch typePair(c.typ(), c2.typ()) {
case typePair(ContainerArray, ContainerArray):
return compareArrayArray(c.array(), c2.array())
case typePair(ContainerArray, ContainerBitmap):
return compareArrayBitmap(c.array(), c2.bitmap())
case typePair(ContainerBitmap, ContainerArray):
return compareArrayBitmap(c2.array(), c.bitmap())
case typePair(ContainerArray, ContainerRun):
return compareArrayRuns(c.array(), c2.runs())
case typePair(ContainerRun, ContainerArray):
return compareArrayRuns(c2.array(), c.runs())
default:
c3 := xor(c, c2)
if c3.N() != 0 {
return fmt.Errorf("%d bits different between containers", c3.N())
}
}
return nil
}
func unionArrayBitmap(a, b *Container) *Container {
output := b.Clone()
bitmap := output.bitmap()
n := output.N()
for _, v := range a.array() {
if !output.bitmapContains(v) {
bitmap[v/64] |= (1 << uint64(v%64))
n++
}
}
output.setN(n)
return output
}
// unions array b into bitmap a, mutating a in place. The n value
// of a will need to be repaired after the fact.
func unionBitmapArrayInPlace(a, b *Container) *Container {
a = a.Thaw()
bitmap := a.bitmap()
a.setDirty(true)
for _, v := range b.array() {
bitmap[v>>6] |= (uint64(1) << (v % 64))
}
return a
}
func unionBitmapBitmap(a, b *Container) *Container {
// local variables added to prevent BCE checks in loop
// see https://go101.org/article/bounds-check-elimination.html
var (
ab = a.bitmap()[:bitmapN]
bb = b.bitmap()[:bitmapN]
ob = make([]uint64, bitmapN)[:bitmapN]
n int32
)
for i := 0; i < bitmapN; i++ {
ob[i] = ab[i] | bb[i]
n += int32(popcount(ob[i]))
}
output := NewContainerBitmapN(ob, n)
return output
}
// unions bitmap b into bitmap a, mutating a in place. The n value of
// a will need to be repaired after the fact.
func unionBitmapBitmapInPlace(a, b *Container) *Container {
a = a.Thaw()
// local variables added to prevent BCE checks in loop
// see https://go101.org/article/bounds-check-elimination.html
var (
ab = a.bitmap()[:bitmapN]
bb = b.bitmap()[:bitmapN]
)
// Manually unroll loop to make it a little faster.
// TODO(rartoul): Can probably make this a few x faster using
// SIMD instructions.
for i := 0; i < bitmapN; i += 4 {
ab[i] |= bb[i]
ab[i+1] |= bb[i+1]
ab[i+2] |= bb[i+2]
ab[i+3] |= bb[i+3]
}
a.setDirty(true)
return a
}
// unions run b into run a, mutating a in place.
func unionRunRunInPlace(a, b *Container) *Container {
statsHit("unionInPlace/RunRun")
a = a.Thaw()
runs, n := unionInterval16InPlace(a.runs(), b.runs())
a.setRuns(runs)
a.setN(n)
if len(runs) > runMaxSize {
a = a.runToBitmap()
}
return a
}
// unionInterval16InPlace merges two slice of intervals in place (in a).
// The main concept is to go value by value (instead of interval by interval)
// and count `.start` and `.last` points.
// If we get the `state == 0` it means we just built a new interval (`val`),
// and we can set it in `a` at the possition `off`
func unionInterval16InPlace(a, b []Interval16) ([]Interval16, int32) {
n := int32(0)
an, bn := len(a), len(b)
var (
// ai - index of a, aii - subindex (0: a[ai].start, 1: a[ai].last).
ai, aii int = 0, 0
// bi - index of b, bii - subindex (0: b[bi].start, 1: b[bi].last).
bi, bii int = 0, 0
// Offset of a - next available index to set.
off int = 0
// Value to set/append to a at off
val Interval16
// Current state - state equals 0 means we are clear (out of intervals)
// When we start a new interval we add +1 when we get out of interval we add -1.
state int
// subindex (ii) to state mapping
// .start: [0] -> 1
// .last: [1] -> -1
iiMap = [2]int{1, -1}
// If fromB is equal 2 it means that both val.start and val.last come from b,
// so we need to extend a, first
fromB int8
// eval functions evaluates global state and value
eval = func(arr [2]uint16, ii int, onlyB bool) {
if state == 0 && ii == 0 {
// we are clear and start a new interval
val.Start = arr[ii]
if onlyB {
fromB++
}
}
state += iiMap[ii]
if state == 0 {
// we just got out of interval
// ii == 1
val.Last = arr[ii]
if onlyB {
fromB++
}
}
}
// eval2 function is a special variant for eval function
// it's only used when two interval endings are equal, e.g.:
// a: ------------------|
// b: -----------|
// the most important part is to change the global for both endings
// before we check if we're getting out of interval and start the new one.
eval2 = func(arr [2]uint16, i1, i2 int) {
if state == 0 && (i1 == 0 || i2 == 0) {
// we are clear and start a new interval
val.Start = arr[i1]
}
state += iiMap[i1]
state += iiMap[i2]
if state == 0 {
// (i1 == 1 || i2 == 1)
// we just got out of interval
val.Last = arr[i1]
}
}
)
for {
// av, bv reflects a[ai] and b[bi] intervals as an array,
// so we can internally iterate over values (points).
var av, bv [2]uint16
if ai < an && bi < bn {
av[0], av[1] = a[ai].Start, a[ai].Last
bv[0], bv[1] = b[bi].Start, b[bi].Last
if av[aii] < bv[bii] {
// a: |-------------------
// b: |-------------------
eval(av, aii, false)
aii++
} else if av[aii] == bv[bii] {
// a: |-------------------
// b: |-------------------
// or
// a: ------------------|
// b: |-------------------
// or
// a: ------------------|
// b: |------------|
// ...
eval2(av, aii, bii)
aii++
bii++
} else { // bv[bii] < av[aii]
// a: |-------------------
// b: |-------------------
eval(bv, bii, true)
bii++
}
} else if ai < an { // only a left
av[0], av[1] = a[ai].Start, a[ai].Last
eval(av, aii, false)
aii++
} else if bi < bn { // only b left
bv[0], bv[1] = b[bi].Start, b[bi].Last
eval(bv, bii, false)
bii++
} else {
break
}
if state == 0 {
if fromB == 2 {
// val.start and val.last come from b, so we need to extend a, first
a = append(a, Interval16{})
copy(a[off+1:], a[off:])
ai++
an++
}
fromB = 0
a, off = appendInterval16At(a, val, off)
n += int32(val.Last) - int32(val.Start) + 1
}
if aii == 2 {
// move to the next a's interval
aii = 0
ai++
}
if bii == 2 {
// move to the next b's interval
bii = 0
bi++
}
}
if len(a) > 0 {
a = a[:off]
}
return a, n
}
// appendInterval16At appends or sets val in a at off position
// The function returns modified a ([]interval16) and new offset (off)
func appendInterval16At(a []Interval16, val Interval16, off int) ([]Interval16, int) {
if off > 0 && int32(val.Start)-int32(a[off-1].Last) <= 1 {
a[off-1].Last = val.Last
return a, off
}
if off == len(a) {
a = append(a, val)
off++
return a, off
}
a[off] = val
off++
return a, off
}
func difference(a, b *Container) (c *Container) {
if roaringParanoia {
defer func() { c.CheckN() }()
}
if a.N() == 0 || b.N() == MaxContainerVal+1 {
return nil
}
if b.N() == 0 {
return a.Freeze()
}
if a.isArray() {
if b.isArray() {
return differenceArrayArray(a, b)
} else if b.isRun() {
return differenceArrayRun(a, b)
} else {
return differenceArrayBitmap(a, b)
}
} else if a.isRun() {
if b.isArray() {
return differenceRunArray(a, b)
} else if b.isRun() {
return differenceRunRun(a, b)
} else {
return differenceRunBitmap(a, b)
}
} else {
if b.isArray() {
return differenceBitmapArray(a, b)
} else if b.isRun() {
return differenceBitmapRun(a, b)
} else {
return differenceBitmapBitmap(a, b)
}
}
}
// differenceArrayArray computes the difference bween two arrays.
func differenceArrayArray(a, b *Container) *Container {
statsHit("difference/ArrayArray")
output := NewContainerArray(nil)
aa, ab := a.array(), b.array()
na, nb := len(aa), len(ab)
for i, j := 0, 0; i < na; {
va := aa[i]
if j >= nb {
output, _ = output.add(va)
i++
continue
}
vb := ab[j]
if va < vb {
output, _ = output.add(va)
i++
} else if va > vb {
j++
} else {
i, j = i+1, j+1
}
}
return output
}
// differenceArrayRun computes the difference of an array from a run.
func differenceArrayRun(a, b *Container) *Container {
statsHit("difference/ArrayRun")
// func (ac *arrayContainer) iandNotRun16(rc *runContainer16) container {
output := make([]uint16, 0, a.N())
// cardinality upper bound: card(A)
i := 0 // array index
j := 0 // run index
aa, rb := a.array(), b.runs()
// handle overlap
for i < len(aa) {
// keep all array elements before beginning of runs
if aa[i] < rb[j].Start {
output = append(output, aa[i])
i++
continue
}
// if array element in run, skip it
if aa[i] >= rb[j].Start && aa[i] <= rb[j].Last {
i++
continue
}
// if array element larger than current run, check next run
if aa[i] > rb[j].Last {
j++
if j == len(rb) {
break
}
}
}
if i < len(aa) {
// keep all array elements after end of runs
// It's possible that output was converted from array to bitmap in output.add()
// so check container type before proceeding.
output = append(output, aa[i:]...)
}
return NewContainerArray(output)
}
// differenceBitmapRun computes the difference of an bitmap from a run.
func differenceBitmapRun(a, b *Container) *Container {
statsHit("difference/BitmapRun")
output := a.Clone()
for _, run := range b.runs() {
output.bitmapZeroRange(uint64(run.Start), uint64(run.Last)+1)
}
return output
}
// differenceRunArray subtracts the bits in an array container from a run
// container.
func differenceRunArray(a, b *Container) *Container {
statsHit("difference/RunArray")
ra, ab := a.runs(), b.array()
runs := make([]Interval16, 0, len(ra))
bidx := 0
vb := ab[bidx]
RUNLOOP:
for _, run := range ra {
start := run.Start
for vb < run.Start {
bidx++
if bidx >= len(ab) {
break
}
vb = ab[bidx]
}
for vb >= run.Start && vb <= run.Last {
if vb == start {
if vb == 65535 { // overflow
break RUNLOOP
}
start++
bidx++
if bidx >= len(ab) {
break
}
vb = ab[bidx]
continue
}
runs = append(runs, Interval16{Start: start, Last: vb - 1})
if vb == 65535 { // overflow
break RUNLOOP
}
start = vb + 1
bidx++
if bidx >= len(ab) {
break
}
vb = ab[bidx]
}
if start <= run.Last {
runs = append(runs, Interval16{Start: start, Last: run.Last})
}
}
output := NewContainerRun(runs)
output = output.optimize()
return output
}
// differenceRunBitmap computes the difference of an run from a bitmap.
func differenceRunBitmap(a, b *Container) *Container {
statsHit("difference/RunBitmap")
ra := a.runs()
// If a is full, difference is the flip of b.
if len(ra) > 0 && ra[0].Start == 0 && ra[0].Last == 65535 {
return flipBitmap(b)
}
bb := b.bitmap()[:1024]
runs := make([]Interval16, 0, len(ra))
for _, inputRun := range ra {
run := inputRun
add := true
for bit := inputRun.Start; bit <= inputRun.Last; bit++ {
idx, exp := int(bit>>6), bit&63
if (bb[idx]>>exp)&1 != 0 {
if run.Start == bit {
if bit == 65535 { //overflow
add = false
}
run.Start++
} else if bit == run.Last {
run.Last--
} else {
run.Last = bit - 1
if run.Last >= run.Start {
if len(runs) >= runMaxSize {
asBitmap := a.runToBitmap()
return differenceBitmapBitmap(asBitmap, b)
}
runs = append(runs, run)
}
run.Start = bit + 1
run.Last = inputRun.Last
}
if run.Start > run.Last {
break
}
}
if bit == 65535 { //overflow
break
}
}
if run.Start <= run.Last {
if add {
if len(runs) >= runMaxSize {
asBitmap := a.runToBitmap()
return differenceBitmapBitmap(asBitmap, b)
}
runs = append(runs, run)
}
}
}
output := NewContainerRun(runs)
if output.N() < ArrayMaxSize && int32(len(runs)) > output.N()/2 {
output = output.runToArray()
} else if len(runs) > runMaxSize {
output = output.runToBitmap()
}
return output
}
// differenceRunRun computes the difference of two runs.
func differenceRunRun(a, b *Container) *Container {
statsHit("difference/RunRun")
ra, rb := a.runs(), b.runs()
apos := 0 // current a-run index
bpos := 0 // current b-run index
astart := ra[apos].Start
alast := ra[apos].Last
bstart := rb[bpos].Start
blast := rb[bpos].Last
alen := len(ra)
blen := len(rb)
runs := make([]Interval16, 0, alen+blen) // TODO allocate max then truncate? or something else
// cardinality upper bound: sum of number of runs
// each B-run could split an A-run in two, up to len(b.runs) times
for apos < alen && bpos < blen {
switch {
case alast < bstart:
// current A-run entirely precedes current B-run: keep full A-run, advance to next A-run
runs = append(runs, Interval16{Start: astart, Last: alast})
apos++
if apos < alen {
astart = ra[apos].Start
alast = ra[apos].Last
}
case blast < astart:
// current B-run entirely precedes current A-run: advance to next B-run
bpos++
if bpos < blen {
bstart = rb[bpos].Start
blast = rb[bpos].Last
}
default:
// overlap
if astart < bstart {
runs = append(runs, Interval16{Start: astart, Last: bstart - 1})
}
if alast > blast {
astart = blast + 1
} else {
apos++
if apos < alen {
astart = ra[apos].Start
alast = ra[apos].Last
}
}
}
}
if apos < alen {
runs = append(runs, Interval16{Start: astart, Last: alast})
apos++
if apos < alen {
runs = append(runs, ra[apos:]...)
}
}
return NewContainerRun(runs)
}
func differenceArrayBitmap(a, b *Container) *Container {
statsHit("difference/ArrayBitmap")
output := make([]uint16, 0, a.N())
bitmap := b.bitmap()
for _, va := range a.array() {
bmidx := va / 64
bidx := va % 64
mask := uint64(1) << bidx
b := bitmap[bmidx]
if mask&^b > 0 {
output = append(output, va)
}
}
return NewContainerArray(output)
}
func differenceBitmapArray(a, b *Container) *Container {
statsHit("difference/BitmapArray")
output := a.Clone()
bitmap := output.bitmap()
n := output.N()
for _, v := range b.array() {
if output.bitmapContains(v) {
bitmap[v/64] &^= (uint64(1) << uint(v%64))
n--
}
}
output.setN(n)
if n < ArrayMaxSize {
output = output.bitmapToArray()
}
return output
}
func differenceBitmapBitmap(a, b *Container) *Container {
statsHit("difference/BitmapBitmap")
// local variables added to prevent BCE checks in loop
// see https://go101.org/article/bounds-check-elimination.html
var (
ab = a.bitmap()[:bitmapN]
bb = b.bitmap()[:bitmapN]
ob = make([]uint64, bitmapN)[:bitmapN]
n int32
)
for i := 0; i < bitmapN; i++ {
ob[i] = ab[i] & (^bb[i])
n += int32(popcount(ob[i]))
}
output := NewContainerBitmapN(ob, n)
if output.N() < ArrayMaxSize {
output = output.bitmapToArray()
}
return output
}
func xor(a, b *Container) (c *Container) {
if roaringParanoia {
defer func() { c.CheckN() }()
}
if a.N() == 0 {
return b.Freeze()
}
if b.N() == 0 {
return a.Freeze()
}
if a.isArray() {
if b.isArray() {
return xorArrayArray(a, b)
} else if b.isRun() {
return xorArrayRun(a, b)
} else {
return xorArrayBitmap(a, b)
}
} else if a.isRun() {
if b.isArray() {
return xorArrayRun(b, a)
} else if b.isRun() {
return xorRunRun(a, b)
} else {
return xorBitmapRun(b, a)
}
} else {
if b.isArray() {
return xorArrayBitmap(b, a)
} else if b.isRun() {
return xorBitmapRun(a, b)
} else {
return xorBitmapBitmap(a, b)
}
}
}
func xorArrayArray(a, b *Container) *Container {
statsHit("xor/ArrayArray")
aa, ab := a.array(), b.array()
output := make([]uint16, len(aa)+len(ab))
i, j, k := 0, 0, 0
for i < len(aa) && j < len(ab) {
va, vb := aa[i], ab[j]
switch {
case va < vb:
// The a side is lower, so copy those first.
for i < len(aa) && aa[i] < vb {
output[k] = aa[i]
i++
k++
}
case va > vb:
// The b side is lower, so copy those first.
for j < len(ab) && ab[j] < va {
output[k] = ab[j]
j++
k++
}
default:
// Both are equal.
// Skip them.
i++
j++
}
}
switch {
case i < len(aa):
k += copy(output[k:], aa[i:])
case j < len(ab):
k += copy(output[k:], ab[j:])
}
if k == cap(output) {
return NewContainerArray(output)
}
return NewContainerArrayCopy(output[:k])
}
func xorArrayBitmap(a, b *Container) *Container {
statsHit("xor/ArrayBitmap")
output := b.Clone()
for _, v := range a.array() {
if b.bitmapContains(v) {
output, _ = output.remove(v)
} else {
output, _ = output.add(v)
}
}
// It's possible that output was converted from bitmap to array in output.remove()
// so we only do this conversion if output is still a bitmap container.
if output.typ() == ContainerBitmap && output.count() < ArrayMaxSize {
output = output.bitmapToArray()
}
return output
}
func xorBitmapBitmap(a, b *Container) *Container {
statsHit("xor/BitmapBitmap")
// local variables added to prevent BCE checks in loop
// see https://go101.org/article/bounds-check-elimination.html
var (
ab = a.bitmask()
bb = b.bitmask()
ob = [1024]uint64{}
n int32
)
_, _ = &ab[0], &bb[0]
for i := range ob {
ob[i] = ab[i] ^ bb[i]
n += int32(popcount(ob[i]))
}
output := NewContainerBitmapN(ob[:], n)
if n < ArrayMaxSize {
output = output.bitmapToArray()
}
return output
}
// shift() shifts the contents of c by one. It returns
// the new container and a bool indicating whether a
// carry bit was shifted out.
func shift(c *Container) (*Container, bool) {
if c.N() == 0 {
return nil, false
}
if c.isArray() {
return shiftArray(c)
} else if c.isRun() {
return shiftRun(c)
}
return shiftBitmap(c)
}
// shiftArray is an array-specific implementation of shift().
func shiftArray(a *Container) (*Container, bool) {
statsHit("shift/Array")
carry := false
aa := a.array()
output := make([]uint16, 0, len(aa))
for _, v := range aa {
if v+1 == 0 { // overflow
carry = true
} else {
output = append(output, v+1)
}
}
return NewContainerArray(output), carry
}
// shiftBitmap is a bitmap-specific implementation of shift().
func shiftBitmap(a *Container) (*Container, bool) {
statsHit("shift/Bitmap")
carry := uint64(0)
output := NewContainerBitmapN(nil, 0)
ba, bo := a.bitmap(), output.bitmap()
lastCarry := uint64(0)
for i, v := range ba {
carry = v >> 63
v = v<<1 | lastCarry
bo[i] = v
lastCarry = carry
}
output.setN(a.N() - int32(carry))
return output, carry != 0
}
// shiftRun is a run-specific implementation of shift().
func shiftRun(a *Container) (*Container, bool) {
statsHit("shift/Run")
carry := false
ra := a.runs()
ro := make([]Interval16, 0, len(ra))
for _, v := range ra {
if v.Start+1 == 0 { // final run was 1 bit on container edge
carry = true
break
} else if v.Last+1 == 0 { // final run ends on container edge
v.Start++
carry = true
} else {
v.Start++
v.Last++
carry = false
}
ro = append(ro, v)
}
return NewContainerRun(ro), carry
}
// opType represents a type of operation.
type opType uint8
const (
opTypeAdd = opType(0)
opTypeRemove = opType(1)
opTypeAddBatch = opType(2)
opTypeRemoveBatch = opType(3)
opTypeAddRoaring = opType(4)
opTypeRemoveRoaring = opType(5)
)
var opTypes = []string{
"add",
"remove",
"addN",
"removeN",
"addRoaring",
"removeRoaring",
}
// op represents an operation on the bitmap.
type op struct {
typ opType
opN int
value uint64
values []uint64
roaring []byte
}
// OpInfo is a description of an op.
type OpInfo struct {
Type string
OpN int
Size int
}
func (op *op) info() (info OpInfo) {
if int(op.typ) < len(opTypes) {
info.Type = opTypes[op.typ]
} else {
info.Type = fmt.Sprintf("unknown-type-%d", op.typ)
}
info.OpN = op.opN
info.Size = op.size()
return info
}
// apply executes the operation against a bitmap.
func (op *op) apply(b *Bitmap) (changed bool) {
switch op.typ {
case opTypeAdd:
return b.DirectAdd(op.value)
case opTypeRemove:
return b.remove(op.value)
case opTypeAddBatch:
changed = b.DirectAddN(op.values...) > 0
case opTypeRemoveBatch:
changed = b.DirectRemoveN(op.values...) > 0
case opTypeAddRoaring:
changedN, _, _ := b.ImportRoaringBits(op.roaring, false, false, 0)
changed = changedN != 0
case opTypeRemoveRoaring:
changedN, _, _ := b.ImportRoaringBits(op.roaring, true, false, 0)
changed = changedN != 0
default:
panic(fmt.Sprintf("invalid op type: %d", op.typ))
}
return changed
}
// WriteTo writes op to the w.
func (op *op) WriteTo(w io.Writer) (n int64, err error) {
buf := make([]byte, op.encodeSize())
// Write type and value.
buf[0] = byte(op.typ)
switch op.typ {
case opTypeAdd, opTypeRemove:
binary.LittleEndian.PutUint64(buf[1:9], op.value)
case opTypeAddBatch, opTypeRemoveBatch:
binary.LittleEndian.PutUint64(buf[1:9], uint64(len(op.values)))
p := 13 // start of values (skip 4 for checksum)
for _, v := range op.values {
binary.LittleEndian.PutUint64(buf[p:p+8], v)
p += 8
}
case opTypeAddRoaring, opTypeRemoveRoaring:
binary.LittleEndian.PutUint64(buf[1:9], uint64(len(op.roaring)))
binary.LittleEndian.PutUint32(buf[13:17], uint32(op.opN))
default:
return 0, fmt.Errorf("can't marshal unknown op type %d", op.typ)
}
// Add checksum at the end.
h := fnv.New32a()
_, _ = h.Write(buf[0:9])
_, _ = h.Write(buf[13:])
if op.typ == 4 || op.typ == 5 {
_, _ = h.Write(op.roaring)
}
binary.LittleEndian.PutUint32(buf[9:13], h.Sum32())
// Write to writer.
nn, err := w.Write(buf)
if err != nil {
return int64(nn), err
}
if op.typ == 4 || op.typ == 5 {
var nn2 int
// separate write so we don't have to copy the whole thing
nn2, err = w.Write(op.roaring)
nn += nn2
}
return int64(nn), err
}
var minOpSize = 13
var maxBatchSize = uint64(1 << 59)
// UnmarshalBinary decodes data into an op.
func (op *op) UnmarshalBinary(data []byte) error {
if len(data) < minOpSize {
return fmt.Errorf("op data out of bounds: len=%d", len(data))
}
statsHit("op/UnmarshalBinary")
op.typ = opType(data[0])
// op.value will actually contain the length of values for batch ops, or
// length of the roaring bitmap for roaring bitmap ops
op.value = binary.LittleEndian.Uint64(data[1:9])
// Verify checksum.
h := fnv.New32a()
_, _ = h.Write(data[0:9])
switch op.typ {
case opTypeAdd, opTypeRemove:
op.opN = 1
case opTypeAddBatch, opTypeRemoveBatch:
// This ensures that in doing 13+op.value*8, the max int won't be exceeded and a wrap around case
// (resulting in a negative value) won't occur in the slice indexing while writing
if op.value > maxBatchSize {
return fmt.Errorf("maximum operation size exceeded")
}
if len(data) < int(13+op.value*8) {
return fmt.Errorf("op data truncated - expected %d, got %d", 13+op.value*8, len(data))
}
_, _ = h.Write(data[13 : 13+op.value*8])
op.opN = int(op.value)
op.values = make([]uint64, op.opN)
for i := range op.values {
start := 13 + i*8
op.values[i] = binary.LittleEndian.Uint64(data[start : start+8])
}
op.value = 0
case opTypeAddRoaring, opTypeRemoveRoaring:
if len(data) < int(13+4+op.value) {
return fmt.Errorf("op data truncated - expected %d, got %d", 13+op.value, len(data))
}
op.opN = int(binary.LittleEndian.Uint32(data[13:17]))
// gratuitous hack: treat any roaring write as having at least 1/8 of
// its length in bits, even if it didn't actually change things.
if op.opN < int(op.value/8) {
op.opN = int(op.value / 8)
}
op.roaring = data[17 : 17+op.value]
_, _ = h.Write(data[13 : 17+op.value])
// op.value = 0
default:
return fmt.Errorf("unknown op type: %d", op.typ)
}
if chk := binary.LittleEndian.Uint32(data[9:13]); chk != h.Sum32() {
return fmt.Errorf("checksum mismatch: type %d, exp=%08x, got=%08x", op.typ, h.Sum32(), chk)
}
return nil
}
// size returns the encoded size of the op, in bytes.
func (op *op) size() int {
switch op.typ {
case opTypeAdd, opTypeRemove:
return 1 + 8 + 4
case opTypeAddBatch, opTypeRemoveBatch:
return 1 + 8 + 4 + len(op.values)*8
case opTypeAddRoaring, opTypeRemoveRoaring:
return 1 + 8 + 4 + 4 + len(op.roaring)
}
panic(fmt.Errorf("op size() called on unknown op type %d", op.typ))
}
// size returns the size needed to encode the op, in bytes. for
// roaring ops, this does not include the roaring data, which is
// already encoded.
func (op *op) encodeSize() int {
switch op.typ {
case opTypeAdd, opTypeRemove:
return 1 + 8 + 4
case opTypeAddBatch, opTypeRemoveBatch:
return 1 + 8 + 4 + len(op.values)*8
case opTypeAddRoaring, opTypeRemoveRoaring:
return 1 + 8 + 4 + 4
}
panic(fmt.Errorf("op encodeSize() called on unknown op type %d", op.typ))
}
// count returns the number of bits the operation mutates.
func (op *op) count() int {
switch op.typ {
case 0, 1:
return 1
case 2, 3:
return len(op.values)
case 4, 5:
return op.opN
default:
panic(fmt.Errorf("unknown operation type: %d", op.typ))
}
}
func highbits(v uint64) uint64 { return v >> 16 }
func lowbits(v uint64) uint16 { return uint16(v & 0xFFFF) }
// search32 returns the index of value in a. If value is not found, it works the
// same way as search64.
func search32(a []uint16, value uint16) int32 {
statsHit("search32")
// Optimize for elements and the last element.
n := int32(len(a))
if n == 0 {
return -1
} else if a[n-1] == value {
return n - 1
}
// Otherwise perform binary search for exact match.
lo, hi := int32(0), n-1
for lo+16 <= hi {
i := int32(uint((lo + hi)) >> 1)
v := a[i]
if v < value {
lo = i + 1
} else if v > value {
hi = i - 1
} else {
return i
}
}
// If an exact match isn't found then return a negative index.
for ; lo <= hi; lo++ {
v := a[lo]
if v == value {
return lo
} else if v > value {
break
}
}
return -(lo + 1)
}
// search64 returns the index of value in a. If value is not found, -1 * (1 +
// the index where v would be if it were inserted) is returned. This is done in
// order to both signal that value was not found (negative number), and also
// return information about where v would go if it were inserted. The +1 offset
// is necessary due to the case where v is not found, but would go at index 0.
// since negative 0 is no different from positive 0, we offset the returned
// negative indices by 1. See the test for this function for examples.
func search64(a []uint64, value uint64) int {
statsHit("search64")
// Optimize for elements and the last element.
n := len(a)
if n == 0 {
return -1
} else if a[n-1] == value {
return n - 1
}
// Otherwise perform binary search for exact match.
lo, hi := 0, n-1
for lo+16 <= hi {
i := int(uint((lo + hi)) >> 1)
v := a[i]
if v < value {
lo = i + 1
} else if v > value {
hi = i - 1
} else {
return i
}
}
// If an exact match isn't found then return a negative index.
for ; lo <= hi; lo++ {
v := a[lo]
if v == value {
return lo
} else if v > value {
break
}
}
return -(lo + 1)
}
// trailingZeroN returns the number of trailing zeros in v.
// v must be greater than zero.
func trailingZeroN(v uint64) int {
return bits.TrailingZeros64(v)
}
// ErrorList represents a list of errors.
type ErrorList []error
func (a ErrorList) Error() string {
switch len(a) {
case 0:
return "no errors"
case 1:
return a[0].Error()
}
return fmt.Sprintf("%s (and %d more errors)", a[0], len(a)-1)
}
// Append appends an error to the list. If err is an ErrorList then all errors are appended.
func (a *ErrorList) Append(err error) {
switch err := err.(type) {
case ErrorList:
*a = append(*a, err...)
default:
*a = append(*a, err)
}
}
// AppendWithPrefix appends an error to the list and includes a prefix.
func (a *ErrorList) AppendWithPrefix(err error, prefix string) {
switch err := err.(type) {
case ErrorList:
for i := range err {
*a = append(*a, fmt.Errorf("%s%s", prefix, err[i]))
}
default:
*a = append(*a, fmt.Errorf("%s%s", prefix, err))
}
}
// xorArrayRun computes the exclusive or of an array and a run container.
func xorArrayRun(a, b *Container) *Container {
statsHit("xor/ArrayRun")
output := NewContainerRun(nil)
aa, rb := a.array(), b.runs()
na, nb := len(aa), len(rb)
var vb Interval16
var va uint16
lastI, lastJ := -1, -1
n := int32((0))
for i, j := 0, 0; i < na || j < nb; {
if i < na && i != lastI {
va = aa[i]
}
if j < nb && j != lastJ {
vb = rb[j]
}
lastI = i
lastJ = j
if i < na && (j >= nb || va < vb.Start) { //before
n += output.runAppendInterval(Interval16{Start: va, Last: va})
i++
} else if j < nb && (i >= na || va > vb.Last) { //after
n += output.runAppendInterval(vb)
j++
} else if va > vb.Start {
if va < vb.Last {
n += output.runAppendInterval(Interval16{Start: vb.Start, Last: va - 1})
i++
vb.Start = va + 1
if vb.Start > vb.Last {
j++
}
} else if va > vb.Last {
n += output.runAppendInterval(vb)
j++
} else { // va == vb.last
vb.Last--
if vb.Start <= vb.Last {
n += output.runAppendInterval(vb)
}
j++
i++
}
} else { // we know va == vb.start
if vb.Start == MaxContainerVal { // protect overflow
j++
} else {
vb.Start++
if vb.Start > vb.Last {
j++
}
}
i++
}
}
output.setN(n)
if n < ArrayMaxSize {
output = output.runToArray()
} else if len(output.runs()) > runMaxSize {
output = output.runToBitmap()
}
return output
}
// xorCompare computes first exclusive run between two runs.
func xorCompare(x *xorstm) (r1 Interval16, hasData bool) {
hasData = false
if !x.vaValid || !x.vbValid {
if x.vbValid {
x.vbValid = false
return x.vb, true
}
if x.vaValid {
x.vaValid = false
return x.va, true
}
return r1, false
}
if x.va.Last < x.vb.Start { //va before
x.vaValid = false
r1 = x.va
hasData = true
} else if x.vb.Last < x.va.Start { //vb before
x.vbValid = false
r1 = x.vb
hasData = true
} else if x.va.Start == x.vb.Start && x.va.Last == x.vb.Last { // Equal
x.vaValid = false
x.vbValid = false
} else if x.va.Start <= x.vb.Start && x.va.Last >= x.vb.Last { //vb inside
x.vbValid = false
if x.va.Start != x.vb.Start {
r1 = Interval16{Start: x.va.Start, Last: x.vb.Start - 1}
hasData = true
}
if x.vb.Last == MaxContainerVal { // Check for overflow
x.vaValid = false
} else {
x.va.Start = x.vb.Last + 1
if x.va.Start > x.va.Last {
x.vaValid = false
}
}
} else if x.vb.Start <= x.va.Start && x.vb.Last >= x.va.Last { //va inside
x.vaValid = false
if x.vb.Start != x.va.Start {
r1 = Interval16{Start: x.vb.Start, Last: x.va.Start - 1}
hasData = true
}
if x.va.Last == MaxContainerVal { //check for overflow
x.vbValid = false
} else {
x.vb.Start = x.va.Last + 1
if x.vb.Start > x.vb.Last {
x.vbValid = false
}
}
} else if x.va.Start < x.vb.Start && x.va.Last <= x.vb.Last { //va first overlap
x.vaValid = false
r1 = Interval16{Start: x.va.Start, Last: x.vb.Start - 1}
hasData = true
if x.va.Last == MaxContainerVal { // check for overflow
x.vbValid = false
} else {
x.vb.Start = x.va.Last + 1
if x.vb.Start > x.vb.Last {
x.vbValid = false
}
}
} else if x.vb.Start < x.va.Start && x.vb.Last <= x.va.Last { //vb first overlap
x.vbValid = false
r1 = Interval16{Start: x.vb.Start, Last: x.va.Start - 1}
hasData = true
if x.vb.Last == MaxContainerVal { // check for overflow
x.vaValid = false
} else {
x.va.Start = x.vb.Last + 1
if x.va.Start > x.va.Last {
x.vaValid = false
}
}
}
return r1, hasData
}
// stm is state machine used to "xor" iterate over runs.
type xorstm struct {
vaValid, vbValid bool
va, vb Interval16
}
// xorRunRun computes the exclusive or of two run containers.
func xorRunRun(a, b *Container) *Container {
statsHit("xor/RunRun")
ra, rb := a.runs(), b.runs()
na, nb := len(ra), len(rb)
output := NewContainerRun(nil)
lastI, lastJ := -1, -1
state := &xorstm{}
n := int32(0)
for i, j := 0, 0; i < na || j < nb; {
if i < na && lastI != i {
state.va = ra[i]
state.vaValid = true
}
if j < nb && lastJ != j {
state.vb = rb[j]
state.vbValid = true
}
lastI, lastJ = i, j
r1, ok := xorCompare(state)
if ok {
n += output.runAppendInterval(r1)
}
if !state.vaValid {
i++
}
if !state.vbValid {
j++
}
}
l := len(output.runs())
output.setN(n)
if n < ArrayMaxSize && int32(l) > n/2 {
output = output.runToArray()
} else if l > runMaxSize {
output = output.runToBitmap()
}
return output
}
// xorRunRun computes the exclusive or of a bitmap and a run container.
func xorBitmapRun(a, b *Container) *Container {
statsHit("xor/BitmapRun")
output := a.Clone()
for _, run := range b.runs() {
output.bitmapXorRange(uint64(run.Start), uint64(run.Last)+1)
}
return output
}
// CompareBitmapSlice checks whether a bitmap has the same values in it
// that a provided slice does.
func CompareBitmapSlice(b *Bitmap, vals []uint64) (bool, error) {
count := b.Count()
if count != uint64(len(vals)) {
return false, fmt.Errorf("length mismatch: bitmap has %d bits, slice has %d", count, len(vals))
}
for _, v := range vals {
if !b.Contains(v) {
return false, fmt.Errorf("bitmap lacks expected value %d", v)
}
}
return true, nil
}
// CompareBitmapMap checks whether a bitmap has the same values in it
// that a provided map[uint64]struct{} has as keys.
func CompareBitmapMap(b *Bitmap, vals map[uint64]struct{}) (bool, error) {
count := b.Count()
if count != uint64(len(vals)) {
return false, fmt.Errorf("length mismatch: bitmap has %d bits, map has %d", count, len(vals))
}
for v := range vals {
if !b.Contains(v) {
return false, fmt.Errorf("bitmap lacks expected value %d", v)
}
}
return true, nil
}
// BitwiseEqual is used mostly in test cases to confirm that two bitmaps came
// out the same. It does not expect corresponding opN, or OpWriter, but expects
// identical bit contents. It does not expect identical representations; a bitmap
// container can be identical to an array container. It returns a boolean value,
// and also an explanation for a false value.
func (b *Bitmap) BitwiseEqual(c *Bitmap) (bool, error) {
biter, _ := b.Containers.Iterator(0)
citer, _ := c.Containers.Iterator(0)
bn, cn := biter.Next(), citer.Next()
var bk, ck uint64
var bc, cc *Container
bct, cct := 0, 0
for bn && cn {
bk, bc = biter.Value()
ck, cc = citer.Value()
// zero containers are allowed to match no-container
if bk < ck {
if bc.N() == 0 {
bn = biter.Next()
continue
}
}
if ck < bk {
if cc.N() == 0 {
cn = citer.Next()
continue
}
}
bct++
cct++
if bk != ck {
return false, fmt.Errorf("differing keys [%d vs %d]", bk, ck)
}
diff := xor(bc, cc)
if diff.N() != 0 {
return false, fmt.Errorf("differing containers for key %d: %v vs %v", bk, bc, cc)
}
bn, cn = biter.Next(), citer.Next()
}
// only one can have containers left. they should all be empty. so we
// look at any remaining containers, break out of the loop if they're not
// empty, and otherwise keep iterating.
for bn {
bn = biter.Next()
bk, bc = biter.Value()
if bc.N() != 0 {
bct++
break
}
}
for cn {
cn = citer.Next()
ck, cc = citer.Value()
if cc.N() != 0 {
cct++
break
}
}
if bn {
return false, fmt.Errorf("container mismatch: %d vs %d containers, first bitmap has extra container %d [%v bits]", bct, cct, bk, bc)
}
if cn {
return false, fmt.Errorf("container mismatch: %d vs %d containers, second bitmap has extra container %d [%v bits]", bct, cct, ck, cc)
}
return true, nil
}
func popcount(x uint64) uint64 {
return uint64(bits.OnesCount64(x))
}
func popcountAndSlice(s, m []uint64) uint64 {
var (
a = s[:bitmapN]
b = m[:bitmapN]
)
cnt := uint64(0)
for i := 0; i < bitmapN; i++ {
cnt += popcount(a[i] & b[i])
}
return cnt
}
// constants from github.com/RoaringBitmap/roaring
// taken from roaring/util.go
const (
serialCookieNoRunContainer = 12346 // only arrays and bitmaps
serialCookie = 12347 // runs, arrays, and bitmaps
)
func readOfficialHeader(buf []byte) (size uint32, containerTyper func(index uint, card int) byte, header, pos int, haveRuns bool, err error) {
statsHit("readOfficialHeader")
if len(buf) < 8 {
err = fmt.Errorf("buffer too small, expecting at least 8 bytes, was %d", len(buf))
return size, containerTyper, header, pos, haveRuns, err
}
cf := func(index uint, card int) (newType byte) {
newType = ContainerBitmap
if card < ArrayMaxSize {
newType = ContainerArray
}
return newType
}
containerTyper = cf
cookie := binary.LittleEndian.Uint32(buf)
pos += 4
// cookie header
if cookie == serialCookieNoRunContainer {
size = binary.LittleEndian.Uint32(buf[pos:])
pos += 4
} else if cookie&0x0000FFFF == serialCookie {
haveRuns = true
size = uint32(uint16(cookie>>16) + 1) // number of containers
// create is-run-container bitmap
isRunBitmapSize := (int(size) + 7) / 8
if pos+isRunBitmapSize > len(buf) {
err = fmt.Errorf("malformed bitmap, is-run bitmap overruns buffer at %d", pos+isRunBitmapSize)
return size, containerTyper, header, pos, haveRuns, err
}
isRunBitmap := buf[pos : pos+isRunBitmapSize]
pos += isRunBitmapSize
containerTyper = func(index uint, card int) byte {
if isRunBitmap[index/8]&(1<<(index%8)) != 0 {
return ContainerRun
}
return cf(index, card)
}
} else {
err = fmt.Errorf("did not find expected serialCookie in header")
return size, containerTyper, header, pos, haveRuns, err
}
header = pos
if size > (1 << 16) {
err = fmt.Errorf("it is logically impossible to have more than (1<<16) containers")
return size, containerTyper, header, pos, haveRuns, err
}
// descriptive header
if pos+2*2*int(size) >= len(buf) {
err = fmt.Errorf("malformed bitmap, key-cardinality slice overruns buffer at %d", pos+2*2*int(size))
return size, containerTyper, header, pos, haveRuns, err
}
pos += 2 * 2 * int(size) // moving pos past keycount
return size, containerTyper, header, pos, haveRuns, err
}
// handledIter and handledIters are wrappers around Bitmap Container iterators
// and assist with the unionIntoTarget algorithm by abstracting away some tedious
// operations.
type handledIter struct {
iter ContainerIterator
hasNext bool
handled bool
}
type handledIters []handledIter
func (w handledIters) next() bool {
hasNext := false
for i, wrapped := range w {
next := wrapped.iter.Next()
w[i].hasNext = next
w[i].handled = false
if next {
hasNext = true
}
}
return hasNext
}
// Check all the iters from startIdx and up to see whether their next
// key is the given key; if it is, mark them as handled.
func (w handledIters) markItersWithKeyAsHandled(startIdx int, key uint64) {
for i := startIdx; i < len(w); i++ {
wrapped := w[i]
currKey, _ := wrapped.iter.Value()
if currKey == key {
w[i].handled = true
}
}
}
func (w handledIters) calculateSummaryStats(key uint64) containerUnionSummaryStats {
summary := containerUnionSummaryStats{}
for _, iter := range w {
// Calculate key-level statistics here
currKey, currContainer := iter.iter.Value()
if key == currKey {
summary.c++
summary.n += int64(currContainer.N())
if currContainer.N() == MaxContainerVal+1 {
summary.hasMaxRange = true
summary.n = MaxContainerVal + 1
return summary
}
}
}
return summary
}
// Summary statistics about all the containers in the other bitmaps
// that share the same key so we can make smarter union strategy
// decisions.
type containerUnionSummaryStats struct {
// Estimated cardinality of the union of all containers with the same
// key across all bitmaps. This calculation is very rough as we just sum
// the cardinality of the container across the different bitmaps which could
// result in very inflated values, but it allows us to avoid allocating
// expensive bitmaps when unioning many low density containers.
n int64
// Containers found with this key. May be inaccurate if hasMaxRange is true.
c int
// Whether any of the containers with the specified keys are storing every possible
// value that they can. If so, we can short-circuit all the unioning logic and use
// a RLE container with a single value in it. This is an optimization to
// avoid using an expensive bitmap container for bitmaps that have some
// extremely dense containers.
hasMaxRange bool
}
// DifferenceInPlace returns the bitwise difference of b and others, modifying
// b in place.
func (b *Bitmap) DifferenceInPlace(others ...*Bitmap) {
bSize := b.Size()
// If b doesn't have any containers then return early.
if bSize == 0 {
return
}
const staticSize = 20
var (
requiredSliceSize = len(others)
// To avoid having to allocate a slice every time, if the number of bitmaps
// being differenced is small enough (i.e. smaller than staticSize), we can
// just use this stack-allocated array.
staticHandledIters = [staticSize]handledIter{}
bitmapIters handledIters
target = b
removeContainerKeys = make([]uint64, 0, bSize)
)
if requiredSliceSize <= staticSize {
bitmapIters = staticHandledIters[:0]
} else {
bitmapIters = make(handledIters, 0, requiredSliceSize)
}
for _, other := range others {
otherIter, _ := other.Containers.Iterator(0)
if otherIter.Next() {
bitmapIters = append(bitmapIters, handledIter{
iter: otherIter,
hasNext: true,
})
}
}
targetItr, _ := target.Containers.Iterator(0)
// Go through all the containers and remove the other bits
for targetItr.Next() {
targetKey, curContainer := targetItr.Value()
// no point in subtracting things from an empty container.
if curContainer.N() == 0 {
removeContainerKeys = append(removeContainerKeys, targetKey)
}
// Loop until every iters current value has been handled.
for _, iIter := range bitmapIters {
if !iIter.hasNext {
continue
}
iKey, iContainer := iIter.iter.Value()
for iKey < targetKey {
iIter.hasNext = iIter.iter.Next()
if iIter.hasNext {
iKey, iContainer = iIter.iter.Value()
} else {
break
}
}
if targetKey == iKey {
// note: a nil container is valid, and has N == 0.
if iContainer.N() != 0 {
// Note: This Thaw() may be unnecessary, but some of the
// differenceInPlace code may be assuming the container is
// always writable.
curContainer = curContainer.Thaw().DifferenceInPlace(iContainer)
if curContainer.N() == 0 {
removeContainerKeys = append(removeContainerKeys, targetKey)
break
} else {
b.Containers.Put(targetKey, curContainer)
}
}
iIter.hasNext = iIter.iter.Next()
}
}
}
for _, key := range removeContainerKeys {
b.Containers.Remove(key)
}
target.Containers.Repair()
}
func (c *Container) DifferenceInPlace(other *Container) *Container {
if other == nil {
return c
}
if other.isArray() {
if c.isArray() {
return differenceArrayArrayInPlace(c, other)
} else if c.isBitmap() {
return differenceBitmapArrayInPlace(c, other)
} else if c.isRun() {
return differenceRunArrayInPlace(c, other)
}
} else if other.isBitmap() {
if c.isArray() {
return differenceArrayBitmapInPlace(c, other)
} else if c.isBitmap() {
return differenceBitmapBitmapInPlace(c, other)
} else if c.isRun() {
return differenceRunBitmapInPlace(c, other)
}
} else if other.isRun() {
if c.isArray() {
return differenceArrayRunInPlace(c, other)
} else if c.isBitmap() {
return differenceBitmapRunInPlace(c, other)
} else if c.isRun() {
return differenceRunRunInPlace(c, other)
}
}
return c
}
func differenceArrayArrayInPlace(c, other *Container) *Container {
statsHit("differenceInPlace/ArrayArray")
aa, ab := c.array(), other.array()
na, nb := len(aa), len(ab)
if na == 0 || nb == 0 {
return c
}
n := 0
for i, j := 0, 0; i < na; {
va := aa[i]
if j >= nb {
// nothing more to subtract; copy the remainder, bump n accordingly,
// and be done.
copy(aa[n:], aa[i:])
n += len(aa) - i
break
}
vb := ab[j]
if va < vb {
aa[n] = va
n++
i++
} else if va > vb {
j++
} else {
i, j = i+1, j+1
}
}
aa = aa[:n]
c.setArray(aa)
return c
}
func differenceArrayBitmapInPlace(c, other *Container) *Container {
statsHit("differenceInPlace/ArrayBitmap")
aa := c.array()
n := 0
bitmap := other.bitmap()
if len(aa) == 0 || len(bitmap) == 0 {
return c
}
for _, va := range aa {
bmidx := va / 64
bidx := va % 64
mask := uint64(1) << bidx
b := bitmap[bmidx]
if mask&^b > 0 {
aa[n] = va
n++
}
}
aa = aa[:n]
c.setArray(aa)
return c
}
func differenceArrayRunInPlace(c, other *Container) *Container {
statsHit("differenceInPlace/ArrayRun")
i := 0 // array index
j := 0 // run index
aa, rb := c.array(), other.runs()
if len(aa) == 0 || len(rb) == 0 {
return c
}
n := 0
// handle overlap
for i < len(aa) {
// keep all array elements before beginning of runs
if aa[i] < rb[j].Start {
aa[n] = aa[i]
n++
i++
continue
}
// if array element in run, skip it
if aa[i] >= rb[j].Start && aa[i] <= rb[j].Last {
i++
continue
}
// if array element larger than current run, check next run
if aa[i] > rb[j].Last {
j++
if j == len(rb) {
break
}
}
}
for ; i < len(aa); i++ {
aa[n] = aa[i]
n++
}
aa = aa[:n]
c.setArray(aa)
return c
}
func differenceBitmapArrayInPlace(c, other *Container) *Container {
statsHit("differenceInPlace/BitmapArray")
bitmap := c.bitmap()
ab := other.array()
if len(bitmap) == 0 || len(ab) == 0 {
return c
}
n := c.N()
for _, v := range ab {
if c.bitmapContains(v) {
bitmap[v/64] &^= (uint64(1) << uint(v%64))
n--
}
}
c.setN(n)
if n < ArrayMaxSize {
c = c.bitmapToArray() // With This Work
}
return c
}
func differenceBitmapBitmapInPlace(c, other *Container) *Container {
statsHit("differenceInPlace/BitmapBitmap")
// local variables added to prevent BCE checks in loop
// see https://go101.org/article/bounds-check-elimination.html
a := c.bitmap()
b := other.bitmap()
if len(a) == 0 || len(b) == 0 {
return c
}
var (
ab = a[:bitmapN]
bb = b[:bitmapN]
n int32
)
for i := 0; i < bitmapN; i++ {
ab[i] = ab[i] & (^bb[i])
n += int32(popcount(ab[i]))
}
c.setN(n)
if n < ArrayMaxSize {
c = c.bitmapToArray()
}
return c
}
func differenceBitmapRunInPlace(c, other *Container) *Container {
statsHit("differenceInPlace/BitmapRun")
if len(c.bitmap()) == 0 {
return c
}
for _, run := range other.runs() {
c.bitmapZeroRange(uint64(run.Start), uint64(run.Last)+1)
}
return c
}
func differenceRunArrayInPlace(c, other *Container) *Container {
statsHit("differenceInPlace/RunArray")
ra, ab := c.runs(), other.array()
if len(ra) == 0 || len(ab) == 0 {
return c
}
runs := make([]Interval16, 0, len(ra))
bidx := 0
vb := ab[bidx]
RUNLOOP:
for _, run := range ra {
start := run.Start
for vb < run.Start {
bidx++
if bidx >= len(ab) {
break
}
vb = ab[bidx]
}
for vb >= run.Start && vb <= run.Last {
if vb == start {
if vb == 65535 { // overflow
break RUNLOOP
}
start++
bidx++
if bidx >= len(ab) {
break
}
vb = ab[bidx]
continue
}
runs = append(runs, Interval16{Start: start, Last: vb - 1})
if vb == 65535 { // overflow
break RUNLOOP
}
start = vb + 1
bidx++
if bidx >= len(ab) {
break
}
vb = ab[bidx]
}
if start <= run.Last {
runs = append(runs, Interval16{Start: start, Last: run.Last})
}
}
c.setRuns(runs)
c.n = 0
for _, run := range runs {
c.n += int32(run.Last-run.Start) + 1
}
return c.optimize()
}
func differenceRunBitmapInPlace(c, other *Container) *Container {
statsHit("differenceInPlace/RunBitmap")
ra := c.runs()
if len(ra) == 0 || len(other.bitmap()) == 0 {
return c
}
// If a is full, difference is the flip of b.
if len(ra) > 0 && ra[0].Start == 0 && ra[0].Last == 65535 {
clone := other.Clone()
bitmap := clone.bitmap()
for i, word := range other.bitmap() {
bitmap[i] = ^word
}
c.setTyp(ContainerBitmap)
c.setMapped(false)
c.setBitmap(bitmap)
c.setN(c.count())
return c
}
runs := make([]Interval16, 0, len(ra))
for _, inputRun := range ra {
run := inputRun
add := true
for bit := inputRun.Start; bit <= inputRun.Last; bit++ {
if other.bitmapContains(bit) {
if run.Start == bit {
if bit == 65535 { //overflow
add = false
}
run.Start++
} else if bit == run.Last {
run.Last--
} else {
run.Last = bit - 1
if run.Last >= run.Start {
runs = append(runs, run)
}
run.Start = bit + 1
run.Last = inputRun.Last
}
if run.Start > run.Last {
break
}
}
if bit == 65535 { //overflow
break
}
}
if run.Start <= run.Last {
if add {
runs = append(runs, run)
}
}
}
c.setRuns(runs)
c.n = 0
for _, run := range runs {
c.n += int32(run.Last-run.Start) + 1
}
if c.N() < ArrayMaxSize && int32(len(runs)) > c.N()/2 {
c = c.runToArray()
} else if len(runs) > runMaxSize {
c = c.runToBitmap()
}
return c
}
func differenceRunRunInPlace(c, other *Container) *Container {
statsHit("differenceInPlace/RunRun")
ra, rb := c.runs(), other.runs()
if len(ra) == 0 || len(rb) == 0 {
return c
}
apos := 0 // current a-run index
bpos := 0 // current b-run index
astart := ra[apos].Start
alast := ra[apos].Last
bstart := rb[bpos].Start
blast := rb[bpos].Last
alen := len(ra)
blen := len(rb)
runs := make([]Interval16, 0, alen+blen) // TODO allocate max then truncate? or something else
// cardinality upper bound: sum of number of runs
// each B-run could split an A-run in two, up to len(b.runs) times
for apos < alen && bpos < blen {
switch {
case alast < bstart:
// current A-run entirely precedes current B-run: keep full A-run, advance to next A-run
runs = append(runs, Interval16{Start: astart, Last: alast})
apos++
if apos < alen {
astart = ra[apos].Start
alast = ra[apos].Last
}
case blast < astart:
// current B-run entirely precedes current A-run: advance to next B-run
bpos++
if bpos < blen {
bstart = rb[bpos].Start
blast = rb[bpos].Last
}
default:
// overlap
if astart < bstart {
runs = append(runs, Interval16{Start: astart, Last: bstart - 1})
}
if alast > blast {
astart = blast + 1
} else {
apos++
if apos < alen {
astart = ra[apos].Start
alast = ra[apos].Last
}
}
}
}
if apos < alen {
runs = append(runs, Interval16{Start: astart, Last: alast})
apos++
if apos < alen {
runs = append(runs, ra[apos:]...)
}
}
c.setRuns(runs)
c.n = 0
for _, run := range runs {
c.n += int32(run.Last-run.Start) + 1
}
return c
}
// Roaring encodes the bitmap in the Pilosa roaring
// format. Convenience wrapper around WriteTo.
func (b *Bitmap) Roaring() []byte {
buf := &bytes.Buffer{}
_, err := b.WriteTo(buf)
if err != nil {
panic(err) // I don't believe this can happen when writing to a bytes.Buffer
}
return buf.Bytes()
}
//RBF exports to be reconsidered as we progress
func (b *Bitmap) Put(key uint64, c *Container) {
b.Containers.Put(key, c)
}
func AsBitmap(c *Container) []uint64 {
return c.bitmap()
}
func AsArray(c *Container) []uint16 {
return c.array()
}
func ContainerType(c *Container) byte {
return c.typ()
}
func AsRuns(c *Container) []Interval16 {
return c.runs()
}
func ConvertArrayToBitmap(c *Container) *Container {
return c.arrayToBitmap()
}
func ConvertRunToBitmap(c *Container) *Container {
return c.runToBitmap()
}
// Optimize yields a container with the same bits as c, but
// adjusted to the smallest-storage type by Roaring rules (thus,
// runs where that's smaller, otherwise arrays for N < 4096 and
// bitmaps for N >= 4096).
func Optimize(c *Container) *Container {
return c.optimize()
}
func Union(a, b *Container) (c *Container) {
c = union(a, b)
// c can be have arrays that are too big, and need
// to be optimized into raw bitmaps.
return c.optimize()
}
func Difference(a, b *Container) *Container {
return difference(a, b)
}
func Intersect(x, y *Container) *Container {
return intersect(x, y)
}
func IntersectionCount(x, y *Container) int32 {
return intersectionCount(x, y)
}
// Add yields a container identical to c, but with the given bit set; added
// is true if the bit wasn't previously set. It is unspecified whether
// the original container is modified.
func (c *Container) Add(v uint16) (newC *Container, added bool) {
return c.add(v)
}
// Add yields a container identical to c, but with the given bit cleared;
// removed is true if the bit was previously set. It is unspecified whether
// the original container is modified.
func (c *Container) Remove(v uint16) (c2 *Container, removed bool) {
return c.remove(v)
}
func (c *Container) Max() uint16 {
return c.max()
}
func (c *Container) CountRange(start, end int32) (n int32) {
return c.countRange(start, end)
}
// UnionInPlace yields a container containing all the bits set in
// either c or other. It may, or may not, modify c. The resulting
// container's count, as returned by c.N(), may be incorrect; see
// (*Container).Repair(). Do not freeze a container produced by this
// operation before repairing it. We don't want this to call repair
// immediately because it can be faster for Bitmap.UnionInPlace to do
// it all at once after potentially many Container.UnionInPlace calls.
func (c *Container) UnionInPlace(other *Container) (r *Container) {
return c.unionInPlace(other)
}
func (c *Container) Difference(other *Container) *Container {
return difference(c, other)
}
// Slice returns an array of the values in the container as uint16.
// Do NOT modify the result; it could be the container's actual storage.
func (c *Container) Slice() (r []uint16) {
if c == nil {
return r
}
switch c.typ() {
case ContainerArray:
r = c.array()
case ContainerBitmap:
r = make([]uint16, c.N())
n := int32(0)
for i, word := range c.bitmap() {
for word != 0 {
t := word & -word
if roaringParanoia {
if n >= c.N() {
panic("bitmap has more bits set than container.n")
}
}
r[n] = uint16((i*64 + int(popcount(t-1))))
n++
word ^= t
}
}
case ContainerRun:
r = make([]uint16, c.N())
n := 0
for _, run := range c.runs() {
for v := int(run.Start); v <= int(run.Last); v++ {
r[n] = uint16(v)
n++
}
}
}
return r
}
func fromArray16(a []uint16) []byte {
return (*[8192]byte)(unsafe.Pointer(&a[0]))[: len(a)*2 : len(a)*2]
}
func fromArray64(a []uint64) []byte {
return (*[8192]byte)(unsafe.Pointer(&a[0]))[:8192:8192]
}
func fromInterval16(a []Interval16) []byte {
return (*[8192]byte)(unsafe.Pointer(&a[0]))[: len(a)*4 : len(a)*4]
}