neoneo-go/pkg/vm/slot.go
Roman Khimov ee05f73b6f vm: simplify slot and make it private
Hiding refcounter inside a slot is actually a good idea, but it makes the
structure somewhat bigger, especially given that the refcounter is the same
and belongs more to VM or Context. New structure is a bit more efficient:

name                    old time/op    new time/op    delta
ScriptFibonacci-8          672µs ± 2%     644µs ± 0%  -4.15%  (p=0.008 n=5+5)
ScriptNestedRefCount-8    1.08ms ± 1%    1.05ms ± 2%  -2.56%  (p=0.008 n=5+5)
ScriptPushPop/4-8         1.52µs ± 1%    1.47µs ± 1%  -3.14%  (p=0.008 n=5+5)
ScriptPushPop/16-8        3.66µs ± 1%    3.54µs ± 1%  -3.24%  (p=0.008 n=5+5)
ScriptPushPop/128-8       24.7µs ± 1%    23.2µs ± 1%  -6.14%  (p=0.008 n=5+5)
ScriptPushPop/1024-8       183µs ± 1%     173µs ± 1%  -5.01%  (p=0.008 n=5+5)

name                    old alloc/op   new alloc/op   delta
ScriptFibonacci-8          114kB ± 0%     114kB ± 0%    ~     (p=0.079 n=4+5)
ScriptNestedRefCount-8     241kB ± 0%     241kB ± 0%    ~     (p=0.333 n=5+4)
ScriptPushPop/4-8           160B ± 0%      160B ± 0%    ~     (all equal)
ScriptPushPop/16-8          640B ± 0%      640B ± 0%    ~     (all equal)
ScriptPushPop/128-8       8.70kB ± 0%    8.70kB ± 0%    ~     (all equal)
ScriptPushPop/1024-8      73.2kB ± 0%    73.2kB ± 0%    ~     (all equal)

name                    old allocs/op  new allocs/op  delta
ScriptFibonacci-8          3.17k ± 0%     3.17k ± 0%  -0.03%  (p=0.008 n=5+5)
ScriptNestedRefCount-8     10.7k ± 0%     10.7k ± 0%    ~     (all equal)
ScriptPushPop/4-8           8.00 ± 0%      8.00 ± 0%    ~     (all equal)
ScriptPushPop/16-8          32.0 ± 0%      32.0 ± 0%    ~     (all equal)
ScriptPushPop/128-8          259 ± 0%       259 ± 0%    ~     (all equal)
ScriptPushPop/1024-8       2.05k ± 0%     2.05k ± 0%    ~     (all equal)

It'd be especially nice to internalize static slot, but as we can't compare
slices it's not possible.
2021-12-01 21:36:25 +03:00

66 lines
1.3 KiB
Go

package vm
import (
"encoding/json"
"github.com/nspcc-dev/neo-go/pkg/vm/stackitem"
)
// slot is a fixed-size slice of stack items.
type slot []stackitem.Item
// init sets static slot size to n. It is intended to be used only by INITSSLOT.
func (s *slot) init(n int) {
if *s != nil {
panic("already initialized")
}
*s = make([]stackitem.Item, n)
}
// Set sets i-th storage slot.
func (s slot) Set(i int, item stackitem.Item, refs *refCounter) {
if s[i] == item {
return
}
old := s[i]
s[i] = item
if old != nil {
refs.Remove(old)
}
refs.Add(item)
}
// Get returns item contained in i-th slot.
func (s slot) Get(i int) stackitem.Item {
if item := s[i]; item != nil {
return item
}
return stackitem.Null{}
}
// Clear removes all slot variables from reference counter.
func (s slot) Clear(refs *refCounter) {
for _, item := range s {
refs.Remove(item)
}
}
// Size returns slot size.
func (s slot) Size() int {
if s == nil {
panic("not initialized")
}
return len(s)
}
// MarshalJSON implements JSON marshalling interface.
func (s slot) MarshalJSON() ([]byte, error) {
arr := make([]json.RawMessage, len(s))
for i := range s {
data, err := stackitem.ToJSONWithTypes(s[i])
if err == nil {
arr[i] = data
}
}
return json.Marshal(arr)
}