mirror of
https://github.com/ceph/ceph-csi.git
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728 lines
21 KiB
Go
728 lines
21 KiB
Go
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// Copyright (c) 2012-2022 The ANTLR Project. All rights reserved.
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// Use of this file is governed by the BSD 3-clause license that
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// can be found in the LICENSE.txt file in the project root.
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package antlr
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import (
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"fmt"
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"golang.org/x/exp/slices"
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"strconv"
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)
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var _emptyPredictionContextHash int
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func init() {
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_emptyPredictionContextHash = murmurInit(1)
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_emptyPredictionContextHash = murmurFinish(_emptyPredictionContextHash, 0)
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}
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func calculateEmptyHash() int {
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return _emptyPredictionContextHash
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}
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const (
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// BasePredictionContextEmptyReturnState represents {@code $} in an array in full context mode, $
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// doesn't mean wildcard:
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//
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// $ + x = [$,x]
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//
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// Here,
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//
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// $ = EmptyReturnState
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BasePredictionContextEmptyReturnState = 0x7FFFFFFF
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)
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// TODO: JI These are meant to be atomics - this does not seem to match the Java runtime here
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//
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//goland:noinspection GoUnusedGlobalVariable
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var (
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BasePredictionContextglobalNodeCount = 1
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BasePredictionContextid = BasePredictionContextglobalNodeCount
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)
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const (
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PredictionContextEmpty = iota
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PredictionContextSingleton
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PredictionContextArray
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)
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// PredictionContext is a go idiomatic implementation of PredictionContext that does not rty to
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// emulate inheritance from Java, and can be used without an interface definition. An interface
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// is not required because no user code will ever need to implement this interface.
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type PredictionContext struct {
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cachedHash int
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pcType int
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parentCtx *PredictionContext
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returnState int
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parents []*PredictionContext
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returnStates []int
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}
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func NewEmptyPredictionContext() *PredictionContext {
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nep := &PredictionContext{}
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nep.cachedHash = calculateEmptyHash()
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nep.pcType = PredictionContextEmpty
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nep.returnState = BasePredictionContextEmptyReturnState
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return nep
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}
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func NewBaseSingletonPredictionContext(parent *PredictionContext, returnState int) *PredictionContext {
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pc := &PredictionContext{}
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pc.pcType = PredictionContextSingleton
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pc.returnState = returnState
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pc.parentCtx = parent
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if parent != nil {
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pc.cachedHash = calculateHash(parent, returnState)
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} else {
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pc.cachedHash = calculateEmptyHash()
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}
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return pc
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}
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func SingletonBasePredictionContextCreate(parent *PredictionContext, returnState int) *PredictionContext {
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if returnState == BasePredictionContextEmptyReturnState && parent == nil {
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// someone can pass in the bits of an array ctx that mean $
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return BasePredictionContextEMPTY
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}
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return NewBaseSingletonPredictionContext(parent, returnState)
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}
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func NewArrayPredictionContext(parents []*PredictionContext, returnStates []int) *PredictionContext {
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// Parent can be nil only if full ctx mode and we make an array
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// from {@link //EMPTY} and non-empty. We merge {@link //EMPTY} by using
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// nil parent and
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// returnState == {@link //EmptyReturnState}.
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hash := murmurInit(1)
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for _, parent := range parents {
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hash = murmurUpdate(hash, parent.Hash())
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}
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for _, returnState := range returnStates {
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hash = murmurUpdate(hash, returnState)
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}
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hash = murmurFinish(hash, len(parents)<<1)
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nec := &PredictionContext{}
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nec.cachedHash = hash
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nec.pcType = PredictionContextArray
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nec.parents = parents
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nec.returnStates = returnStates
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return nec
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}
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func (p *PredictionContext) Hash() int {
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return p.cachedHash
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}
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func (p *PredictionContext) Equals(other Collectable[*PredictionContext]) bool {
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switch p.pcType {
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case PredictionContextEmpty:
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otherP := other.(*PredictionContext)
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return other == nil || otherP == nil || otherP.isEmpty()
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case PredictionContextSingleton:
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return p.SingletonEquals(other)
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case PredictionContextArray:
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return p.ArrayEquals(other)
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}
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return false
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}
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func (p *PredictionContext) ArrayEquals(o Collectable[*PredictionContext]) bool {
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if o == nil {
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return false
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}
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other := o.(*PredictionContext)
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if other == nil || other.pcType != PredictionContextArray {
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return false
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}
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if p.cachedHash != other.Hash() {
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return false // can't be same if hash is different
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}
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// Must compare the actual array elements and not just the array address
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//
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return slices.Equal(p.returnStates, other.returnStates) &&
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slices.EqualFunc(p.parents, other.parents, func(x, y *PredictionContext) bool {
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return x.Equals(y)
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})
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}
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func (p *PredictionContext) SingletonEquals(other Collectable[*PredictionContext]) bool {
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if other == nil {
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return false
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}
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otherP := other.(*PredictionContext)
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if otherP == nil {
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return false
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}
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if p.cachedHash != otherP.Hash() {
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return false // Can't be same if hash is different
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}
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if p.returnState != otherP.getReturnState(0) {
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return false
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}
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// Both parents must be nil if one is
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if p.parentCtx == nil {
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return otherP.parentCtx == nil
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}
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return p.parentCtx.Equals(otherP.parentCtx)
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}
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func (p *PredictionContext) GetParent(i int) *PredictionContext {
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switch p.pcType {
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case PredictionContextEmpty:
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return nil
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case PredictionContextSingleton:
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return p.parentCtx
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case PredictionContextArray:
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return p.parents[i]
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}
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return nil
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}
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func (p *PredictionContext) getReturnState(i int) int {
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switch p.pcType {
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case PredictionContextArray:
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return p.returnStates[i]
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default:
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return p.returnState
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}
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}
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func (p *PredictionContext) GetReturnStates() []int {
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switch p.pcType {
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case PredictionContextArray:
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return p.returnStates
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default:
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return []int{p.returnState}
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}
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}
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func (p *PredictionContext) length() int {
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switch p.pcType {
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case PredictionContextArray:
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return len(p.returnStates)
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default:
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return 1
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}
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}
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func (p *PredictionContext) hasEmptyPath() bool {
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switch p.pcType {
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case PredictionContextSingleton:
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return p.returnState == BasePredictionContextEmptyReturnState
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}
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return p.getReturnState(p.length()-1) == BasePredictionContextEmptyReturnState
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}
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func (p *PredictionContext) String() string {
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switch p.pcType {
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case PredictionContextEmpty:
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return "$"
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case PredictionContextSingleton:
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var up string
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if p.parentCtx == nil {
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up = ""
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} else {
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up = p.parentCtx.String()
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}
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if len(up) == 0 {
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if p.returnState == BasePredictionContextEmptyReturnState {
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return "$"
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}
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return strconv.Itoa(p.returnState)
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}
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return strconv.Itoa(p.returnState) + " " + up
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case PredictionContextArray:
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if p.isEmpty() {
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return "[]"
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}
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s := "["
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for i := 0; i < len(p.returnStates); i++ {
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if i > 0 {
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s = s + ", "
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}
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if p.returnStates[i] == BasePredictionContextEmptyReturnState {
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s = s + "$"
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continue
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}
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s = s + strconv.Itoa(p.returnStates[i])
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if !p.parents[i].isEmpty() {
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s = s + " " + p.parents[i].String()
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} else {
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s = s + "nil"
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}
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}
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return s + "]"
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default:
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return "unknown"
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}
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}
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func (p *PredictionContext) isEmpty() bool {
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switch p.pcType {
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case PredictionContextEmpty:
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return true
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case PredictionContextArray:
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// since EmptyReturnState can only appear in the last position, we
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// don't need to verify that size==1
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return p.returnStates[0] == BasePredictionContextEmptyReturnState
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default:
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return false
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}
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}
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func (p *PredictionContext) Type() int {
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return p.pcType
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}
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func calculateHash(parent *PredictionContext, returnState int) int {
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h := murmurInit(1)
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h = murmurUpdate(h, parent.Hash())
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h = murmurUpdate(h, returnState)
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return murmurFinish(h, 2)
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}
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// Convert a {@link RuleContext} tree to a {@link BasePredictionContext} graph.
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// Return {@link //EMPTY} if {@code outerContext} is empty or nil.
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// /
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func predictionContextFromRuleContext(a *ATN, outerContext RuleContext) *PredictionContext {
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if outerContext == nil {
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outerContext = ParserRuleContextEmpty
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}
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// if we are in RuleContext of start rule, s, then BasePredictionContext
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// is EMPTY. Nobody called us. (if we are empty, return empty)
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if outerContext.GetParent() == nil || outerContext == ParserRuleContextEmpty {
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return BasePredictionContextEMPTY
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}
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// If we have a parent, convert it to a BasePredictionContext graph
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parent := predictionContextFromRuleContext(a, outerContext.GetParent().(RuleContext))
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state := a.states[outerContext.GetInvokingState()]
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transition := state.GetTransitions()[0]
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return SingletonBasePredictionContextCreate(parent, transition.(*RuleTransition).followState.GetStateNumber())
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}
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func merge(a, b *PredictionContext, rootIsWildcard bool, mergeCache *JPCMap) *PredictionContext {
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// Share same graph if both same
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//
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if a == b || a.Equals(b) {
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return a
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}
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if a.pcType == PredictionContextSingleton && b.pcType == PredictionContextSingleton {
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return mergeSingletons(a, b, rootIsWildcard, mergeCache)
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}
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// At least one of a or b is array
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// If one is $ and rootIsWildcard, return $ as wildcard
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if rootIsWildcard {
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if a.isEmpty() {
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return a
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}
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if b.isEmpty() {
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return b
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}
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}
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// Convert either Singleton or Empty to arrays, so that we can merge them
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//
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ara := convertToArray(a)
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arb := convertToArray(b)
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return mergeArrays(ara, arb, rootIsWildcard, mergeCache)
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}
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func convertToArray(pc *PredictionContext) *PredictionContext {
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switch pc.Type() {
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case PredictionContextEmpty:
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return NewArrayPredictionContext([]*PredictionContext{}, []int{})
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case PredictionContextSingleton:
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return NewArrayPredictionContext([]*PredictionContext{pc.GetParent(0)}, []int{pc.getReturnState(0)})
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default:
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// Already an array
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}
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return pc
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}
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// mergeSingletons merges two Singleton [PredictionContext] instances.
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//
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// Stack tops equal, parents merge is same return left graph.
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// <embed src="images/SingletonMerge_SameRootSamePar.svg"
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// type="image/svg+xml"/></p>
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//
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// <p>Same stack top, parents differ merge parents giving array node, then
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// remainders of those graphs. A new root node is created to point to the
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// merged parents.<br>
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// <embed src="images/SingletonMerge_SameRootDiffPar.svg"
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// type="image/svg+xml"/></p>
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//
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// <p>Different stack tops pointing to same parent. Make array node for the
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// root where both element in the root point to the same (original)
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// parent.<br>
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// <embed src="images/SingletonMerge_DiffRootSamePar.svg"
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// type="image/svg+xml"/></p>
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//
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// <p>Different stack tops pointing to different parents. Make array node for
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// the root where each element points to the corresponding original
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// parent.<br>
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// <embed src="images/SingletonMerge_DiffRootDiffPar.svg"
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// type="image/svg+xml"/></p>
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//
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// @param a the first {@link SingletonBasePredictionContext}
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// @param b the second {@link SingletonBasePredictionContext}
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// @param rootIsWildcard {@code true} if this is a local-context merge,
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// otherwise false to indicate a full-context merge
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// @param mergeCache
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// /
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func mergeSingletons(a, b *PredictionContext, rootIsWildcard bool, mergeCache *JPCMap) *PredictionContext {
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if mergeCache != nil {
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previous, present := mergeCache.Get(a, b)
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if present {
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return previous
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|
}
|
||
|
|
previous, present = mergeCache.Get(b, a)
|
||
|
|
if present {
|
||
|
|
return previous
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
rootMerge := mergeRoot(a, b, rootIsWildcard)
|
||
|
|
if rootMerge != nil {
|
||
|
|
if mergeCache != nil {
|
||
|
|
mergeCache.Put(a, b, rootMerge)
|
||
|
|
}
|
||
|
|
return rootMerge
|
||
|
|
}
|
||
|
|
if a.returnState == b.returnState {
|
||
|
|
parent := merge(a.parentCtx, b.parentCtx, rootIsWildcard, mergeCache)
|
||
|
|
// if parent is same as existing a or b parent or reduced to a parent,
|
||
|
|
// return it
|
||
|
|
if parent.Equals(a.parentCtx) {
|
||
|
|
return a // ax + bx = ax, if a=b
|
||
|
|
}
|
||
|
|
if parent.Equals(b.parentCtx) {
|
||
|
|
return b // ax + bx = bx, if a=b
|
||
|
|
}
|
||
|
|
// else: ax + ay = a'[x,y]
|
||
|
|
// merge parents x and y, giving array node with x,y then remainders
|
||
|
|
// of those graphs. dup a, a' points at merged array.
|
||
|
|
// New joined parent so create a new singleton pointing to it, a'
|
||
|
|
spc := SingletonBasePredictionContextCreate(parent, a.returnState)
|
||
|
|
if mergeCache != nil {
|
||
|
|
mergeCache.Put(a, b, spc)
|
||
|
|
}
|
||
|
|
return spc
|
||
|
|
}
|
||
|
|
// a != b payloads differ
|
||
|
|
// see if we can collapse parents due to $+x parents if local ctx
|
||
|
|
var singleParent *PredictionContext
|
||
|
|
if a.Equals(b) || (a.parentCtx != nil && a.parentCtx.Equals(b.parentCtx)) { // ax +
|
||
|
|
// bx =
|
||
|
|
// [a,b]x
|
||
|
|
singleParent = a.parentCtx
|
||
|
|
}
|
||
|
|
if singleParent != nil { // parents are same
|
||
|
|
// sort payloads and use same parent
|
||
|
|
payloads := []int{a.returnState, b.returnState}
|
||
|
|
if a.returnState > b.returnState {
|
||
|
|
payloads[0] = b.returnState
|
||
|
|
payloads[1] = a.returnState
|
||
|
|
}
|
||
|
|
parents := []*PredictionContext{singleParent, singleParent}
|
||
|
|
apc := NewArrayPredictionContext(parents, payloads)
|
||
|
|
if mergeCache != nil {
|
||
|
|
mergeCache.Put(a, b, apc)
|
||
|
|
}
|
||
|
|
return apc
|
||
|
|
}
|
||
|
|
// parents differ and can't merge them. Just pack together
|
||
|
|
// into array can't merge.
|
||
|
|
// ax + by = [ax,by]
|
||
|
|
payloads := []int{a.returnState, b.returnState}
|
||
|
|
parents := []*PredictionContext{a.parentCtx, b.parentCtx}
|
||
|
|
if a.returnState > b.returnState { // sort by payload
|
||
|
|
payloads[0] = b.returnState
|
||
|
|
payloads[1] = a.returnState
|
||
|
|
parents = []*PredictionContext{b.parentCtx, a.parentCtx}
|
||
|
|
}
|
||
|
|
apc := NewArrayPredictionContext(parents, payloads)
|
||
|
|
if mergeCache != nil {
|
||
|
|
mergeCache.Put(a, b, apc)
|
||
|
|
}
|
||
|
|
return apc
|
||
|
|
}
|
||
|
|
|
||
|
|
// Handle case where at least one of {@code a} or {@code b} is
|
||
|
|
// {@link //EMPTY}. In the following diagrams, the symbol {@code $} is used
|
||
|
|
// to represent {@link //EMPTY}.
|
||
|
|
//
|
||
|
|
// <h2>Local-Context Merges</h2>
|
||
|
|
//
|
||
|
|
// <p>These local-context merge operations are used when {@code rootIsWildcard}
|
||
|
|
// is true.</p>
|
||
|
|
//
|
||
|
|
// <p>{@link //EMPTY} is superset of any graph return {@link //EMPTY}.<br>
|
||
|
|
// <embed src="images/LocalMerge_EmptyRoot.svg" type="image/svg+xml"/></p>
|
||
|
|
//
|
||
|
|
// <p>{@link //EMPTY} and anything is {@code //EMPTY}, so merged parent is
|
||
|
|
// {@code //EMPTY} return left graph.<br>
|
||
|
|
// <embed src="images/LocalMerge_EmptyParent.svg" type="image/svg+xml"/></p>
|
||
|
|
//
|
||
|
|
// <p>Special case of last merge if local context.<br>
|
||
|
|
// <embed src="images/LocalMerge_DiffRoots.svg" type="image/svg+xml"/></p>
|
||
|
|
//
|
||
|
|
// <h2>Full-Context Merges</h2>
|
||
|
|
//
|
||
|
|
// <p>These full-context merge operations are used when {@code rootIsWildcard}
|
||
|
|
// is false.</p>
|
||
|
|
//
|
||
|
|
// <p><embed src="images/FullMerge_EmptyRoots.svg" type="image/svg+xml"/></p>
|
||
|
|
//
|
||
|
|
// <p>Must keep all contexts {@link //EMPTY} in array is a special value (and
|
||
|
|
// nil parent).<br>
|
||
|
|
// <embed src="images/FullMerge_EmptyRoot.svg" type="image/svg+xml"/></p>
|
||
|
|
//
|
||
|
|
// <p><embed src="images/FullMerge_SameRoot.svg" type="image/svg+xml"/></p>
|
||
|
|
//
|
||
|
|
// @param a the first {@link SingletonBasePredictionContext}
|
||
|
|
// @param b the second {@link SingletonBasePredictionContext}
|
||
|
|
// @param rootIsWildcard {@code true} if this is a local-context merge,
|
||
|
|
// otherwise false to indicate a full-context merge
|
||
|
|
// /
|
||
|
|
func mergeRoot(a, b *PredictionContext, rootIsWildcard bool) *PredictionContext {
|
||
|
|
if rootIsWildcard {
|
||
|
|
if a.pcType == PredictionContextEmpty {
|
||
|
|
return BasePredictionContextEMPTY // // + b =//
|
||
|
|
}
|
||
|
|
if b.pcType == PredictionContextEmpty {
|
||
|
|
return BasePredictionContextEMPTY // a +// =//
|
||
|
|
}
|
||
|
|
} else {
|
||
|
|
if a.isEmpty() && b.isEmpty() {
|
||
|
|
return BasePredictionContextEMPTY // $ + $ = $
|
||
|
|
} else if a.isEmpty() { // $ + x = [$,x]
|
||
|
|
payloads := []int{b.getReturnState(-1), BasePredictionContextEmptyReturnState}
|
||
|
|
parents := []*PredictionContext{b.GetParent(-1), nil}
|
||
|
|
return NewArrayPredictionContext(parents, payloads)
|
||
|
|
} else if b.isEmpty() { // x + $ = [$,x] ($ is always first if present)
|
||
|
|
payloads := []int{a.getReturnState(-1), BasePredictionContextEmptyReturnState}
|
||
|
|
parents := []*PredictionContext{a.GetParent(-1), nil}
|
||
|
|
return NewArrayPredictionContext(parents, payloads)
|
||
|
|
}
|
||
|
|
}
|
||
|
|
return nil
|
||
|
|
}
|
||
|
|
|
||
|
|
// Merge two {@link ArrayBasePredictionContext} instances.
|
||
|
|
//
|
||
|
|
// <p>Different tops, different parents.<br>
|
||
|
|
// <embed src="images/ArrayMerge_DiffTopDiffPar.svg" type="image/svg+xml"/></p>
|
||
|
|
//
|
||
|
|
// <p>Shared top, same parents.<br>
|
||
|
|
// <embed src="images/ArrayMerge_ShareTopSamePar.svg" type="image/svg+xml"/></p>
|
||
|
|
//
|
||
|
|
// <p>Shared top, different parents.<br>
|
||
|
|
// <embed src="images/ArrayMerge_ShareTopDiffPar.svg" type="image/svg+xml"/></p>
|
||
|
|
//
|
||
|
|
// <p>Shared top, all shared parents.<br>
|
||
|
|
// <embed src="images/ArrayMerge_ShareTopSharePar.svg"
|
||
|
|
// type="image/svg+xml"/></p>
|
||
|
|
//
|
||
|
|
// <p>Equal tops, merge parents and reduce top to
|
||
|
|
// {@link SingletonBasePredictionContext}.<br>
|
||
|
|
// <embed src="images/ArrayMerge_EqualTop.svg" type="image/svg+xml"/></p>
|
||
|
|
//
|
||
|
|
//goland:noinspection GoBoolExpressions
|
||
|
|
func mergeArrays(a, b *PredictionContext, rootIsWildcard bool, mergeCache *JPCMap) *PredictionContext {
|
||
|
|
if mergeCache != nil {
|
||
|
|
previous, present := mergeCache.Get(a, b)
|
||
|
|
if present {
|
||
|
|
if runtimeConfig.parserATNSimulatorTraceATNSim {
|
||
|
|
fmt.Println("mergeArrays a=" + a.String() + ",b=" + b.String() + " -> previous")
|
||
|
|
}
|
||
|
|
return previous
|
||
|
|
}
|
||
|
|
previous, present = mergeCache.Get(b, a)
|
||
|
|
if present {
|
||
|
|
if runtimeConfig.parserATNSimulatorTraceATNSim {
|
||
|
|
fmt.Println("mergeArrays a=" + a.String() + ",b=" + b.String() + " -> previous")
|
||
|
|
}
|
||
|
|
return previous
|
||
|
|
}
|
||
|
|
}
|
||
|
|
// merge sorted payloads a + b => M
|
||
|
|
i := 0 // walks a
|
||
|
|
j := 0 // walks b
|
||
|
|
k := 0 // walks target M array
|
||
|
|
|
||
|
|
mergedReturnStates := make([]int, len(a.returnStates)+len(b.returnStates))
|
||
|
|
mergedParents := make([]*PredictionContext, len(a.returnStates)+len(b.returnStates))
|
||
|
|
// walk and merge to yield mergedParents, mergedReturnStates
|
||
|
|
for i < len(a.returnStates) && j < len(b.returnStates) {
|
||
|
|
aParent := a.parents[i]
|
||
|
|
bParent := b.parents[j]
|
||
|
|
if a.returnStates[i] == b.returnStates[j] {
|
||
|
|
// same payload (stack tops are equal), must yield merged singleton
|
||
|
|
payload := a.returnStates[i]
|
||
|
|
// $+$ = $
|
||
|
|
bothDollars := payload == BasePredictionContextEmptyReturnState && aParent == nil && bParent == nil
|
||
|
|
axAX := aParent != nil && bParent != nil && aParent.Equals(bParent) // ax+ax
|
||
|
|
// ->
|
||
|
|
// ax
|
||
|
|
if bothDollars || axAX {
|
||
|
|
mergedParents[k] = aParent // choose left
|
||
|
|
mergedReturnStates[k] = payload
|
||
|
|
} else { // ax+ay -> a'[x,y]
|
||
|
|
mergedParent := merge(aParent, bParent, rootIsWildcard, mergeCache)
|
||
|
|
mergedParents[k] = mergedParent
|
||
|
|
mergedReturnStates[k] = payload
|
||
|
|
}
|
||
|
|
i++ // hop over left one as usual
|
||
|
|
j++ // but also Skip one in right side since we merge
|
||
|
|
} else if a.returnStates[i] < b.returnStates[j] { // copy a[i] to M
|
||
|
|
mergedParents[k] = aParent
|
||
|
|
mergedReturnStates[k] = a.returnStates[i]
|
||
|
|
i++
|
||
|
|
} else { // b > a, copy b[j] to M
|
||
|
|
mergedParents[k] = bParent
|
||
|
|
mergedReturnStates[k] = b.returnStates[j]
|
||
|
|
j++
|
||
|
|
}
|
||
|
|
k++
|
||
|
|
}
|
||
|
|
// copy over any payloads remaining in either array
|
||
|
|
if i < len(a.returnStates) {
|
||
|
|
for p := i; p < len(a.returnStates); p++ {
|
||
|
|
mergedParents[k] = a.parents[p]
|
||
|
|
mergedReturnStates[k] = a.returnStates[p]
|
||
|
|
k++
|
||
|
|
}
|
||
|
|
} else {
|
||
|
|
for p := j; p < len(b.returnStates); p++ {
|
||
|
|
mergedParents[k] = b.parents[p]
|
||
|
|
mergedReturnStates[k] = b.returnStates[p]
|
||
|
|
k++
|
||
|
|
}
|
||
|
|
}
|
||
|
|
// trim merged if we combined a few that had same stack tops
|
||
|
|
if k < len(mergedParents) { // write index < last position trim
|
||
|
|
if k == 1 { // for just one merged element, return singleton top
|
||
|
|
pc := SingletonBasePredictionContextCreate(mergedParents[0], mergedReturnStates[0])
|
||
|
|
if mergeCache != nil {
|
||
|
|
mergeCache.Put(a, b, pc)
|
||
|
|
}
|
||
|
|
return pc
|
||
|
|
}
|
||
|
|
mergedParents = mergedParents[0:k]
|
||
|
|
mergedReturnStates = mergedReturnStates[0:k]
|
||
|
|
}
|
||
|
|
|
||
|
|
M := NewArrayPredictionContext(mergedParents, mergedReturnStates)
|
||
|
|
|
||
|
|
// if we created same array as a or b, return that instead
|
||
|
|
// TODO: JI track whether this is possible above during merge sort for speed and possibly avoid an allocation
|
||
|
|
if M.Equals(a) {
|
||
|
|
if mergeCache != nil {
|
||
|
|
mergeCache.Put(a, b, a)
|
||
|
|
}
|
||
|
|
if runtimeConfig.parserATNSimulatorTraceATNSim {
|
||
|
|
fmt.Println("mergeArrays a=" + a.String() + ",b=" + b.String() + " -> a")
|
||
|
|
}
|
||
|
|
return a
|
||
|
|
}
|
||
|
|
if M.Equals(b) {
|
||
|
|
if mergeCache != nil {
|
||
|
|
mergeCache.Put(a, b, b)
|
||
|
|
}
|
||
|
|
if runtimeConfig.parserATNSimulatorTraceATNSim {
|
||
|
|
fmt.Println("mergeArrays a=" + a.String() + ",b=" + b.String() + " -> b")
|
||
|
|
}
|
||
|
|
return b
|
||
|
|
}
|
||
|
|
combineCommonParents(&mergedParents)
|
||
|
|
|
||
|
|
if mergeCache != nil {
|
||
|
|
mergeCache.Put(a, b, M)
|
||
|
|
}
|
||
|
|
if runtimeConfig.parserATNSimulatorTraceATNSim {
|
||
|
|
fmt.Println("mergeArrays a=" + a.String() + ",b=" + b.String() + " -> " + M.String())
|
||
|
|
}
|
||
|
|
return M
|
||
|
|
}
|
||
|
|
|
||
|
|
// Make pass over all M parents and merge any Equals() ones.
|
||
|
|
// Note that we pass a pointer to the slice as we want to modify it in place.
|
||
|
|
//
|
||
|
|
//goland:noinspection GoUnusedFunction
|
||
|
|
func combineCommonParents(parents *[]*PredictionContext) {
|
||
|
|
uniqueParents := NewJStore[*PredictionContext, Comparator[*PredictionContext]](pContextEqInst, PredictionContextCollection, "combineCommonParents for PredictionContext")
|
||
|
|
|
||
|
|
for p := 0; p < len(*parents); p++ {
|
||
|
|
parent := (*parents)[p]
|
||
|
|
_, _ = uniqueParents.Put(parent)
|
||
|
|
}
|
||
|
|
for q := 0; q < len(*parents); q++ {
|
||
|
|
pc, _ := uniqueParents.Get((*parents)[q])
|
||
|
|
(*parents)[q] = pc
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
func getCachedBasePredictionContext(context *PredictionContext, contextCache *PredictionContextCache, visited *VisitRecord) *PredictionContext {
|
||
|
|
if context.isEmpty() {
|
||
|
|
return context
|
||
|
|
}
|
||
|
|
existing, present := visited.Get(context)
|
||
|
|
if present {
|
||
|
|
return existing
|
||
|
|
}
|
||
|
|
|
||
|
|
existing, present = contextCache.Get(context)
|
||
|
|
if present {
|
||
|
|
visited.Put(context, existing)
|
||
|
|
return existing
|
||
|
|
}
|
||
|
|
changed := false
|
||
|
|
parents := make([]*PredictionContext, context.length())
|
||
|
|
for i := 0; i < len(parents); i++ {
|
||
|
|
parent := getCachedBasePredictionContext(context.GetParent(i), contextCache, visited)
|
||
|
|
if changed || !parent.Equals(context.GetParent(i)) {
|
||
|
|
if !changed {
|
||
|
|
parents = make([]*PredictionContext, context.length())
|
||
|
|
for j := 0; j < context.length(); j++ {
|
||
|
|
parents[j] = context.GetParent(j)
|
||
|
|
}
|
||
|
|
changed = true
|
||
|
|
}
|
||
|
|
parents[i] = parent
|
||
|
|
}
|
||
|
|
}
|
||
|
|
if !changed {
|
||
|
|
contextCache.add(context)
|
||
|
|
visited.Put(context, context)
|
||
|
|
return context
|
||
|
|
}
|
||
|
|
var updated *PredictionContext
|
||
|
|
if len(parents) == 0 {
|
||
|
|
updated = BasePredictionContextEMPTY
|
||
|
|
} else if len(parents) == 1 {
|
||
|
|
updated = SingletonBasePredictionContextCreate(parents[0], context.getReturnState(0))
|
||
|
|
} else {
|
||
|
|
updated = NewArrayPredictionContext(parents, context.GetReturnStates())
|
||
|
|
}
|
||
|
|
contextCache.add(updated)
|
||
|
|
visited.Put(updated, updated)
|
||
|
|
visited.Put(context, updated)
|
||
|
|
|
||
|
|
return updated
|
||
|
|
}
|