ledisdb/cmd/vendor/github.com/ugorji/go/codec/fast-path.go.tmpl

443 lines
12 KiB
Cheetah

// //+build ignore
// Copyright (c) 2012-2015 Ugorji Nwoke. All rights reserved.
// Use of this source code is governed by a MIT license found in the LICENSE file.
// ************************************************************
// DO NOT EDIT.
// THIS FILE IS AUTO-GENERATED from fast-path.go.tmpl
// ************************************************************
package codec
// Fast path functions try to create a fast path encode or decode implementation
// for common maps and slices.
//
// We define the functions and register then in this single file
// so as not to pollute the encode.go and decode.go, and create a dependency in there.
// This file can be omitted without causing a build failure.
//
// The advantage of fast paths is:
// - Many calls bypass reflection altogether
//
// Currently support
// - slice of all builtin types,
// - map of all builtin types to string or interface value
// - symetrical maps of all builtin types (e.g. str-str, uint8-uint8)
// This should provide adequate "typical" implementations.
//
// Note that fast track decode functions must handle values for which an address cannot be obtained.
// For example:
// m2 := map[string]int{}
// p2 := []interface{}{m2}
// // decoding into p2 will bomb if fast track functions do not treat like unaddressable.
//
import (
"reflect"
"sort"
)
const fastpathCheckNilFalse = false // for reflect
const fastpathCheckNilTrue = true // for type switch
type fastpathT struct {}
var fastpathTV fastpathT
type fastpathE struct {
rtid uintptr
rt reflect.Type
encfn func(encFnInfo, reflect.Value)
decfn func(decFnInfo, reflect.Value)
}
type fastpathA [{{ .FastpathLen }}]fastpathE
func (x *fastpathA) index(rtid uintptr) int {
// use binary search to grab the index (adapted from sort/search.go)
h, i, j := 0, 0, {{ .FastpathLen }} // len(x)
for i < j {
h = i + (j-i)/2
if x[h].rtid < rtid {
i = h + 1
} else {
j = h
}
}
if i < {{ .FastpathLen }} && x[i].rtid == rtid {
return i
}
return -1
}
type fastpathAslice []fastpathE
func (x fastpathAslice) Len() int { return len(x) }
func (x fastpathAslice) Less(i, j int) bool { return x[i].rtid < x[j].rtid }
func (x fastpathAslice) Swap(i, j int) { x[i], x[j] = x[j], x[i] }
var fastpathAV fastpathA
// due to possible initialization loop error, make fastpath in an init()
func init() {
if !fastpathEnabled {
return
}
i := 0
fn := func(v interface{}, fe func(encFnInfo, reflect.Value), fd func(decFnInfo, reflect.Value)) (f fastpathE) {
xrt := reflect.TypeOf(v)
xptr := reflect.ValueOf(xrt).Pointer()
fastpathAV[i] = fastpathE{xptr, xrt, fe, fd}
i++
return
}
{{range .Values}}{{if not .Primitive}}{{if .Slice }}
fn([]{{ .Elem }}(nil), (encFnInfo).{{ .MethodNamePfx "fastpathEnc" false }}R, (decFnInfo).{{ .MethodNamePfx "fastpathDec" false }}R){{end}}{{end}}{{end}}
{{range .Values}}{{if not .Primitive}}{{if not .Slice }}
fn(map[{{ .MapKey }}]{{ .Elem }}(nil), (encFnInfo).{{ .MethodNamePfx "fastpathEnc" false }}R, (decFnInfo).{{ .MethodNamePfx "fastpathDec" false }}R){{end}}{{end}}{{end}}
sort.Sort(fastpathAslice(fastpathAV[:]))
}
// -- encode
// -- -- fast path type switch
func fastpathEncodeTypeSwitch(iv interface{}, e *Encoder) bool {
switch v := iv.(type) {
{{range .Values}}{{if not .Primitive}}{{if .Slice }}
case []{{ .Elem }}:{{else}}
case map[{{ .MapKey }}]{{ .Elem }}:{{end}}
fastpathTV.{{ .MethodNamePfx "Enc" false }}V(v, fastpathCheckNilTrue, e){{if .Slice }}
case *[]{{ .Elem }}:{{else}}
case *map[{{ .MapKey }}]{{ .Elem }}:{{end}}
fastpathTV.{{ .MethodNamePfx "Enc" false }}V(*v, fastpathCheckNilTrue, e)
{{end}}{{end}}
default:
return false
}
return true
}
func fastpathEncodeTypeSwitchSlice(iv interface{}, e *Encoder) bool {
switch v := iv.(type) {
{{range .Values}}{{if not .Primitive}}{{if .Slice }}
case []{{ .Elem }}:
fastpathTV.{{ .MethodNamePfx "Enc" false }}V(v, fastpathCheckNilTrue, e)
case *[]{{ .Elem }}:
fastpathTV.{{ .MethodNamePfx "Enc" false }}V(*v, fastpathCheckNilTrue, e)
{{end}}{{end}}{{end}}
default:
return false
}
return true
}
func fastpathEncodeTypeSwitchMap(iv interface{}, e *Encoder) bool {
switch v := iv.(type) {
{{range .Values}}{{if not .Primitive}}{{if not .Slice }}
case map[{{ .MapKey }}]{{ .Elem }}:
fastpathTV.{{ .MethodNamePfx "Enc" false }}V(v, fastpathCheckNilTrue, e)
case *map[{{ .MapKey }}]{{ .Elem }}:
fastpathTV.{{ .MethodNamePfx "Enc" false }}V(*v, fastpathCheckNilTrue, e)
{{end}}{{end}}{{end}}
default:
return false
}
return true
}
// -- -- fast path functions
{{range .Values}}{{if not .Primitive}}{{if .Slice }}
func (f encFnInfo) {{ .MethodNamePfx "fastpathEnc" false }}R(rv reflect.Value) {
fastpathTV.{{ .MethodNamePfx "Enc" false }}V(rv.Interface().([]{{ .Elem }}), fastpathCheckNilFalse, f.e)
}
func (_ fastpathT) {{ .MethodNamePfx "Enc" false }}V(v []{{ .Elem }}, checkNil bool, e *Encoder) {
ee := e.e
if checkNil && v == nil {
ee.EncodeNil()
return
}
ee.EncodeArrayStart(len(v))
if e.be {
for _, v2 := range v {
{{ encmd .Elem "v2"}}
}
} else {
for j, v2 := range v {
if j > 0 {
ee.EncodeArrayEntrySeparator()
}
{{ encmd .Elem "v2"}}
}
ee.EncodeArrayEnd()
}
}
{{end}}{{end}}{{end}}
{{range .Values}}{{if not .Primitive}}{{if not .Slice }}
func (f encFnInfo) {{ .MethodNamePfx "fastpathEnc" false }}R(rv reflect.Value) {
fastpathTV.{{ .MethodNamePfx "Enc" false }}V(rv.Interface().(map[{{ .MapKey }}]{{ .Elem }}), fastpathCheckNilFalse, f.e)
}
func (_ fastpathT) {{ .MethodNamePfx "Enc" false }}V(v map[{{ .MapKey }}]{{ .Elem }}, checkNil bool, e *Encoder) {
ee := e.e
if checkNil && v == nil {
ee.EncodeNil()
return
}
ee.EncodeMapStart(len(v))
{{if eq .MapKey "string"}}asSymbols := e.h.AsSymbols&AsSymbolMapStringKeysFlag != 0{{end}}
if e.be {
for k2, v2 := range v {
{{if eq .MapKey "string"}}if asSymbols {
ee.EncodeSymbol(k2)
} else {
ee.EncodeString(c_UTF8, k2)
}{{else}}{{ encmd .MapKey "k2"}}{{end}}
{{ encmd .Elem "v2"}}
}
} else {
j := 0
for k2, v2 := range v {
if j > 0 {
ee.EncodeMapEntrySeparator()
}
{{if eq .MapKey "string"}}if asSymbols {
ee.EncodeSymbol(k2)
} else {
ee.EncodeString(c_UTF8, k2)
}{{else}}{{ encmd .MapKey "k2"}}{{end}}
ee.EncodeMapKVSeparator()
{{ encmd .Elem "v2"}}
j++
}
ee.EncodeMapEnd()
}
}
{{end}}{{end}}{{end}}
// -- decode
// -- -- fast path type switch
func fastpathDecodeTypeSwitch(iv interface{}, d *Decoder) bool {
switch v := iv.(type) {
{{range .Values}}{{if not .Primitive}}{{if .Slice }}
case []{{ .Elem }}:{{else}}
case map[{{ .MapKey }}]{{ .Elem }}:{{end}}
fastpathTV.{{ .MethodNamePfx "Dec" false }}V(v, fastpathCheckNilFalse, false, d){{if .Slice }}
case *[]{{ .Elem }}:{{else}}
case *map[{{ .MapKey }}]{{ .Elem }}:{{end}}
v2, changed2 := fastpathTV.{{ .MethodNamePfx "Dec" false }}V(*v, fastpathCheckNilFalse, true, d)
if changed2 {
*v = v2
}
{{end}}{{end}}
default:
return false
}
return true
}
// -- -- fast path functions
{{range .Values}}{{if not .Primitive}}{{if .Slice }}
{{/*
Slices can change if they
- did not come from an array
- are addressable (from a ptr)
- are settable (e.g. contained in an interface{})
*/}}
func (f decFnInfo) {{ .MethodNamePfx "fastpathDec" false }}R(rv reflect.Value) {
array := f.seq == seqTypeArray
if !array && rv.CanAddr() { // CanSet => CanAddr + Exported
vp := rv.Addr().Interface().(*[]{{ .Elem }})
v, changed := fastpathTV.{{ .MethodNamePfx "Dec" false }}V(*vp, fastpathCheckNilFalse, !array, f.d)
if changed {
*vp = v
}
} else {
v := rv.Interface().([]{{ .Elem }})
fastpathTV.{{ .MethodNamePfx "Dec" false }}V(v, fastpathCheckNilFalse, false, f.d)
}
}
func (f fastpathT) {{ .MethodNamePfx "Dec" false }}X(vp *[]{{ .Elem }}, checkNil bool, d *Decoder) {
v, changed := f.{{ .MethodNamePfx "Dec" false }}V(*vp, checkNil, true, d)
if changed {
*vp = v
}
}
func (_ fastpathT) {{ .MethodNamePfx "Dec" false }}V(v []{{ .Elem }}, checkNil bool, canChange bool,
d *Decoder) (_ []{{ .Elem }}, changed bool) {
dd := d.d
// if dd.isContainerType(valueTypeNil) { dd.TryDecodeAsNil()
if checkNil && dd.TryDecodeAsNil() {
if v != nil {
changed = true
}
return nil, changed
}
slh, containerLenS := d.decSliceHelperStart()
if canChange && v == nil {
if containerLenS <= 0 {
v = []{{ .Elem }}{}
} else {
v = make([]{{ .Elem }}, containerLenS, containerLenS)
}
changed = true
}
if containerLenS == 0 {
if canChange && len(v) != 0 {
v = v[:0]
changed = true
}{{/*
// slh.End() // dd.ReadArrayEnd()
*/}}
return v, changed
}
// for j := 0; j < containerLenS; j++ {
if containerLenS > 0 {
decLen := containerLenS
if containerLenS > cap(v) {
if canChange {
s := make([]{{ .Elem }}, containerLenS, containerLenS)
// copy(s, v[:cap(v)])
v = s
changed = true
} else {
d.arrayCannotExpand(len(v), containerLenS)
decLen = len(v)
}
} else if containerLenS != len(v) {
v = v[:containerLenS]
changed = true
}
// all checks done. cannot go past len.
j := 0
for ; j < decLen; j++ {
{{ if eq .Elem "interface{}" }}d.decode(&v[j]){{ else }}v[j] = {{ decmd .Elem }}{{ end }}
}
if !canChange {
for ; j < containerLenS; j++ {
d.swallow()
}
}
} else {
j := 0
for ; !dd.CheckBreak(); j++ {
if j >= len(v) {
if canChange {
v = append(v, {{ zerocmd .Elem }})
changed = true
} else {
d.arrayCannotExpand(len(v), j+1)
}
}
if j > 0 {
slh.Sep(j)
}
if j < len(v) { // all checks done. cannot go past len.
{{ if eq .Elem "interface{}" }}d.decode(&v[j])
{{ else }}v[j] = {{ decmd .Elem }}{{ end }}
} else {
d.swallow()
}
}
slh.End()
}
return v, changed
}
{{end}}{{end}}{{end}}
{{range .Values}}{{if not .Primitive}}{{if not .Slice }}
{{/*
Maps can change if they are
- addressable (from a ptr)
- settable (e.g. contained in an interface{})
*/}}
func (f decFnInfo) {{ .MethodNamePfx "fastpathDec" false }}R(rv reflect.Value) {
if rv.CanAddr() {
vp := rv.Addr().Interface().(*map[{{ .MapKey }}]{{ .Elem }})
v, changed := fastpathTV.{{ .MethodNamePfx "Dec" false }}V(*vp, fastpathCheckNilFalse, true, f.d)
if changed {
*vp = v
}
} else {
v := rv.Interface().(map[{{ .MapKey }}]{{ .Elem }})
fastpathTV.{{ .MethodNamePfx "Dec" false }}V(v, fastpathCheckNilFalse, false, f.d)
}
}
func (f fastpathT) {{ .MethodNamePfx "Dec" false }}X(vp *map[{{ .MapKey }}]{{ .Elem }}, checkNil bool, d *Decoder) {
v, changed := f.{{ .MethodNamePfx "Dec" false }}V(*vp, checkNil, true, d)
if changed {
*vp = v
}
}
func (_ fastpathT) {{ .MethodNamePfx "Dec" false }}V(v map[{{ .MapKey }}]{{ .Elem }}, checkNil bool, canChange bool,
d *Decoder) (_ map[{{ .MapKey }}]{{ .Elem }}, changed bool) {
dd := d.d
// if dd.isContainerType(valueTypeNil) {dd.TryDecodeAsNil()
if checkNil && dd.TryDecodeAsNil() {
if v != nil {
changed = true
}
return nil, changed
}
containerLen := dd.ReadMapStart()
if canChange && v == nil {
if containerLen > 0 {
v = make(map[{{ .MapKey }}]{{ .Elem }}, containerLen)
} else {
v = make(map[{{ .MapKey }}]{{ .Elem }}) // supports indefinite-length, etc
}
changed = true
}
if containerLen > 0 {
for j := 0; j < containerLen; j++ {
{{ if eq .MapKey "interface{}" }}var mk interface{}
d.decode(&mk)
if bv, bok := mk.([]byte); bok {
mk = string(bv) // maps cannot have []byte as key. switch to string.
}{{ else }}mk := {{ decmd .MapKey }}{{ end }}
mv := v[mk]
{{ if eq .Elem "interface{}" }}d.decode(&mv)
{{ else }}mv = {{ decmd .Elem }}{{ end }}
if v != nil {
v[mk] = mv
}
}
} else if containerLen < 0 {
for j := 0; !dd.CheckBreak(); j++ {
if j > 0 {
dd.ReadMapEntrySeparator()
}
{{ if eq .MapKey "interface{}" }}var mk interface{}
d.decode(&mk)
if bv, bok := mk.([]byte); bok {
mk = string(bv) // maps cannot have []byte as key. switch to string.
}{{ else }}mk := {{ decmd .MapKey }}{{ end }}
dd.ReadMapKVSeparator()
mv := v[mk]
{{ if eq .Elem "interface{}" }}d.decode(&mv)
{{ else }}mv = {{ decmd .Elem }}{{ end }}
if v != nil {
v[mk] = mv
}
}
dd.ReadMapEnd()
}
return v, changed
}
{{end}}{{end}}{{end}}