63 lines
1.1 KiB
Go
63 lines
1.1 KiB
Go
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package vm
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// refCounter represents reference counter for the VM.
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type refCounter struct {
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items map[StackItem]int
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size int
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}
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func newRefCounter() *refCounter {
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return &refCounter{
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items: make(map[StackItem]int),
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}
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}
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// Add adds an item to the reference counter.
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func (r *refCounter) Add(item StackItem) {
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r.size++
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switch item.(type) {
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case *ArrayItem, *StructItem, *MapItem:
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if r.items[item]++; r.items[item] > 1 {
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return
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}
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switch t := item.(type) {
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case *ArrayItem, *StructItem:
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for _, it := range item.Value().([]StackItem) {
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r.Add(it)
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}
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case *MapItem:
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for i := range t.value {
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r.Add(t.value[i].Value)
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}
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}
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}
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}
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// Remove removes item from the reference counter.
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func (r *refCounter) Remove(item StackItem) {
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r.size--
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switch item.(type) {
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case *ArrayItem, *StructItem, *MapItem:
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if r.items[item] > 1 {
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r.items[item]--
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return
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}
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delete(r.items, item)
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switch t := item.(type) {
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case *ArrayItem, *StructItem:
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for _, it := range item.Value().([]StackItem) {
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r.Remove(it)
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}
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case *MapItem:
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for i := range t.value {
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r.Remove(t.value[i].Value)
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}
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}
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}
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}
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