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

491 lines
15 KiB
Cheetah

// +build !notfastpath
// 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.
// Code generated from fast-path.go.tmpl - DO NOT EDIT.
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
// - symmetrical 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 fastpathEnabled = true
type fastpathT struct {}
var fastpathTV fastpathT
type fastpathE struct {
rtid uintptr
rt reflect.Type
encfn func(*Encoder, *codecFnInfo, reflect.Value)
decfn func(*Decoder, *codecFnInfo, 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() {
i := 0
fn := func(v interface{},
fe func(*Encoder, *codecFnInfo, reflect.Value),
fd func(*Decoder, *codecFnInfo, reflect.Value)) (f fastpathE) {
xrt := reflect.TypeOf(v)
xptr := rt2id(xrt)
fastpathAV[i] = fastpathE{xptr, xrt, fe, fd}
i++
return
}
{{/* do not register []uint8 in fast-path */}}
{{range .Values}}{{if not .Primitive}}{{if not .MapKey }}{{if ne .Elem "uint8"}}
fn([]{{ .Elem }}(nil), (*Encoder).{{ .MethodNamePfx "fastpathEnc" false }}R, (*Decoder).{{ .MethodNamePfx "fastpathDec" false }}R){{end}}{{end}}{{end}}{{end}}
{{range .Values}}{{if not .Primitive}}{{if .MapKey }}
fn(map[{{ .MapKey }}]{{ .Elem }}(nil), (*Encoder).{{ .MethodNamePfx "fastpathEnc" false }}R, (*Decoder).{{ .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 not .MapKey }}{{if ne .Elem "uint8"}}
case []{{ .Elem }}:
fastpathTV.{{ .MethodNamePfx "Enc" false }}V(v, e)
case *[]{{ .Elem }}:
fastpathTV.{{ .MethodNamePfx "Enc" false }}V(*v, e){{/*
*/}}{{end}}{{end}}{{end}}{{end}}
{{range .Values}}{{if not .Primitive}}{{if .MapKey }}
case map[{{ .MapKey }}]{{ .Elem }}:
fastpathTV.{{ .MethodNamePfx "Enc" false }}V(v, e)
case *map[{{ .MapKey }}]{{ .Elem }}:
fastpathTV.{{ .MethodNamePfx "Enc" false }}V(*v, e){{/*
*/}}{{end}}{{end}}{{end}}
default:
_ = v // TODO: workaround https://github.com/golang/go/issues/12927 (remove after go 1.6 release)
return false
}
return true
}
{{/*
**** removing this block, as they are never called directly ****
**** removing this block, as they are never called directly ****
func fastpathEncodeTypeSwitchSlice(iv interface{}, e *Encoder) bool {
switch v := iv.(type) {
{{range .Values}}{{if not .Primitive}}{{if not .MapKey }}
case []{{ .Elem }}:
fastpathTV.{{ .MethodNamePfx "Enc" false }}V(v, e)
case *[]{{ .Elem }}:
fastpathTV.{{ .MethodNamePfx "Enc" false }}V(*v, e)
{{end}}{{end}}{{end}}
default:
_ = v // TODO: workaround https://github.com/golang/go/issues/12927 (remove after go 1.6 release)
return false
}
return true
}
func fastpathEncodeTypeSwitchMap(iv interface{}, e *Encoder) bool {
switch v := iv.(type) {
{{range .Values}}{{if not .Primitive}}{{if .MapKey }}
case map[{{ .MapKey }}]{{ .Elem }}:
fastpathTV.{{ .MethodNamePfx "Enc" false }}V(v, e)
case *map[{{ .MapKey }}]{{ .Elem }}:
fastpathTV.{{ .MethodNamePfx "Enc" false }}V(*v, e)
{{end}}{{end}}{{end}}
default:
_ = v // TODO: workaround https://github.com/golang/go/issues/12927 (remove after go 1.6 release)
return false
}
return true
}
**** removing this block, as they are never called directly ****
**** removing this block, as they are never called directly ****
*/}}
// -- -- fast path functions
{{range .Values}}{{if not .Primitive}}{{if not .MapKey }}
func (e *Encoder) {{ .MethodNamePfx "fastpathEnc" false }}R(f *codecFnInfo, rv reflect.Value) {
if f.ti.mbs {
fastpathTV.{{ .MethodNamePfx "EncAsMap" false }}V(rv2i(rv).([]{{ .Elem }}), e)
} else {
fastpathTV.{{ .MethodNamePfx "Enc" false }}V(rv2i(rv).([]{{ .Elem }}), e)
}
}
func (_ fastpathT) {{ .MethodNamePfx "Enc" false }}V(v []{{ .Elem }}, e *Encoder) {
if v == nil { e.e.EncodeNil(); return }
ee, esep := e.e, e.hh.hasElemSeparators()
ee.WriteArrayStart(len(v))
for _, v2 := range v {
if esep { ee.WriteArrayElem() }
{{ encmd .Elem "v2"}}
}
ee.WriteArrayEnd()
}
func (_ fastpathT) {{ .MethodNamePfx "EncAsMap" false }}V(v []{{ .Elem }}, e *Encoder) {
ee, esep := e.e, e.hh.hasElemSeparators()
if len(v)%2 == 1 {
e.errorf("mapBySlice requires even slice length, but got %v", len(v))
return
}
ee.WriteMapStart(len(v) / 2)
for j, v2 := range v {
if esep {
if j%2 == 0 {
ee.WriteMapElemKey()
} else {
ee.WriteMapElemValue()
}
}
{{ encmd .Elem "v2"}}
}
ee.WriteMapEnd()
}
{{end}}{{end}}{{end}}
{{range .Values}}{{if not .Primitive}}{{if .MapKey }}
func (e *Encoder) {{ .MethodNamePfx "fastpathEnc" false }}R(f *codecFnInfo, rv reflect.Value) {
fastpathTV.{{ .MethodNamePfx "Enc" false }}V(rv2i(rv).(map[{{ .MapKey }}]{{ .Elem }}), e)
}
func (_ fastpathT) {{ .MethodNamePfx "Enc" false }}V(v map[{{ .MapKey }}]{{ .Elem }}, e *Encoder) {
if v == nil { e.e.EncodeNil(); return }
ee, esep := e.e, e.hh.hasElemSeparators()
ee.WriteMapStart(len(v))
{{if eq .MapKey "string"}}asSymbols := e.h.AsSymbols&AsSymbolMapStringKeysFlag != 0
{{end}}if e.h.Canonical {
{{if eq .MapKey "interface{}"}}{{/* out of band
*/}}var mksv []byte = make([]byte, 0, len(v)*16) // temporary byte slice for the encoding
e2 := NewEncoderBytes(&mksv, e.hh)
v2 := make([]bytesI, len(v))
var i, l int
var vp *bytesI {{/* put loop variables outside. seems currently needed for better perf */}}
for k2, _ := range v {
l = len(mksv)
e2.MustEncode(k2)
vp = &v2[i]
vp.v = mksv[l:]
vp.i = k2
i++
}
sort.Sort(bytesISlice(v2))
for j := range v2 {
if esep { ee.WriteMapElemKey() }
e.asis(v2[j].v)
if esep { ee.WriteMapElemValue() }
e.encode(v[v2[j].i])
} {{else}}{{ $x := sorttype .MapKey true}}v2 := make([]{{ $x }}, len(v))
var i int
for k, _ := range v {
v2[i] = {{ $x }}(k)
i++
}
sort.Sort({{ sorttype .MapKey false}}(v2))
for _, k2 := range v2 {
if esep { ee.WriteMapElemKey() }
{{if eq .MapKey "string"}}if asSymbols {
ee.EncodeSymbol(k2)
} else {
ee.EncodeString(cUTF8, k2)
}{{else}}{{ $y := printf "%s(k2)" .MapKey }}{{ encmd .MapKey $y }}{{end}}
if esep { ee.WriteMapElemValue() }
{{ $y := printf "v[%s(k2)]" .MapKey }}{{ encmd .Elem $y }}
} {{end}}
} else {
for k2, v2 := range v {
if esep { ee.WriteMapElemKey() }
{{if eq .MapKey "string"}}if asSymbols {
ee.EncodeSymbol(k2)
} else {
ee.EncodeString(cUTF8, k2)
}{{else}}{{ encmd .MapKey "k2"}}{{end}}
if esep { ee.WriteMapElemValue() }
{{ encmd .Elem "v2"}}
}
}
ee.WriteMapEnd()
}
{{end}}{{end}}{{end}}
// -- decode
// -- -- fast path type switch
func fastpathDecodeTypeSwitch(iv interface{}, d *Decoder) bool {
var changed bool
switch v := iv.(type) {
{{range .Values}}{{if not .Primitive}}{{if not .MapKey }}{{if ne .Elem "uint8"}}
case []{{ .Elem }}:
var v2 []{{ .Elem }}
v2, changed = fastpathTV.{{ .MethodNamePfx "Dec" false }}V(v, false, d)
if changed && len(v) > 0 && len(v2) > 0 && !(len(v2) == len(v) && &v2[0] == &v[0]) {
copy(v, v2)
}
case *[]{{ .Elem }}:
var v2 []{{ .Elem }}
v2, changed = fastpathTV.{{ .MethodNamePfx "Dec" false }}V(*v, true, d)
if changed {
*v = v2
}{{/*
*/}}{{end}}{{end}}{{end}}{{end}}
{{range .Values}}{{if not .Primitive}}{{if .MapKey }}{{/*
// maps only change if nil, and in that case, there's no point copying
*/}}
case map[{{ .MapKey }}]{{ .Elem }}:
fastpathTV.{{ .MethodNamePfx "Dec" false }}V(v, false, d)
case *map[{{ .MapKey }}]{{ .Elem }}:
var v2 map[{{ .MapKey }}]{{ .Elem }}
v2, changed = fastpathTV.{{ .MethodNamePfx "Dec" false }}V(*v, true, d)
if changed {
*v = v2
}{{/*
*/}}{{end}}{{end}}{{end}}
default:
_ = v // TODO: workaround https://github.com/golang/go/issues/12927 (remove after go 1.6 release)
return false
}
return true
}
func fastpathDecodeSetZeroTypeSwitch(iv interface{}) bool {
switch v := iv.(type) {
{{range .Values}}{{if not .Primitive}}{{if not .MapKey }}
case *[]{{ .Elem }}:
*v = nil {{/*
*/}}{{end}}{{end}}{{end}}
{{range .Values}}{{if not .Primitive}}{{if .MapKey }}
case *map[{{ .MapKey }}]{{ .Elem }}:
*v = nil {{/*
*/}}{{end}}{{end}}{{end}}
default:
_ = v // TODO: workaround https://github.com/golang/go/issues/12927 (remove after go 1.6 release)
return false
}
return true
}
// -- -- fast path functions
{{range .Values}}{{if not .Primitive}}{{if not .MapKey }}
{{/*
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 (d *Decoder) {{ .MethodNamePfx "fastpathDec" false }}R(f *codecFnInfo, rv reflect.Value) {
if array := f.seq == seqTypeArray; !array && rv.Kind() == reflect.Ptr {
vp := rv2i(rv).(*[]{{ .Elem }})
v, changed := fastpathTV.{{ .MethodNamePfx "Dec" false }}V(*vp, !array, d)
if changed { *vp = v }
} else {
v := rv2i(rv).([]{{ .Elem }})
v2, changed := fastpathTV.{{ .MethodNamePfx "Dec" false }}V(v, !array, d)
if changed && len(v) > 0 && len(v2) > 0 && !(len(v2) == len(v) && &v2[0] == &v[0]) {
copy(v, v2)
}
}
}
func (f fastpathT) {{ .MethodNamePfx "Dec" false }}X(vp *[]{{ .Elem }}, d *Decoder) {
v, changed := f.{{ .MethodNamePfx "Dec" false }}V(*vp, true, d)
if changed { *vp = v }
}
func (_ fastpathT) {{ .MethodNamePfx "Dec" false }}V(v []{{ .Elem }}, canChange bool, d *Decoder) (_ []{{ .Elem }}, changed bool) {
dd := d.d{{/*
// if dd.isContainerType(valueTypeNil) { dd.TryDecodeAsNil()
*/}}
slh, containerLenS := d.decSliceHelperStart()
if containerLenS == 0 {
if canChange {
if v == nil { v = []{{ .Elem }}{} } else if len(v) != 0 { v = v[:0] }
changed = true
}
slh.End()
return v, changed
}
hasLen := containerLenS > 0
var xlen int
if hasLen && canChange {
if containerLenS > cap(v) {
xlen = decInferLen(containerLenS, d.h.MaxInitLen, {{ .Size }})
if xlen <= cap(v) {
v = v[:xlen]
} else {
v = make([]{{ .Elem }}, xlen)
}
changed = true
} else if containerLenS != len(v) {
v = v[:containerLenS]
changed = true
}
}
j := 0
for ; (hasLen && j < containerLenS) || !(hasLen || dd.CheckBreak()); j++ {
if j == 0 && len(v) == 0 && canChange {
if hasLen {
xlen = decInferLen(containerLenS, d.h.MaxInitLen, {{ .Size }})
} else {
xlen = 8
}
v = make([]{{ .Elem }}, xlen)
changed = true
}
// if indefinite, etc, then expand the slice if necessary
var decodeIntoBlank bool
if j >= len(v) {
if canChange {
v = append(v, {{ zerocmd .Elem }})
changed = true
} else {
d.arrayCannotExpand(len(v), j+1)
decodeIntoBlank = true
}
}
slh.ElemContainerState(j)
if decodeIntoBlank {
d.swallow()
} else if dd.TryDecodeAsNil() {
v[j] = {{ zerocmd .Elem }}
} else {
{{ if eq .Elem "interface{}" }}d.decode(&v[j]){{ else }}v[j] = {{ decmd .Elem }}{{ end }}
}
}
if canChange {
if j < len(v) {
v = v[:j]
changed = true
} else if j == 0 && v == nil {
v = make([]{{ .Elem }}, 0)
changed = true
}
}
slh.End()
return v, changed
}
{{end}}{{end}}{{end}}
{{range .Values}}{{if not .Primitive}}{{if .MapKey }}
{{/*
Maps can change if they are
- addressable (from a ptr)
- settable (e.g. contained in an interface{})
*/}}
func (d *Decoder) {{ .MethodNamePfx "fastpathDec" false }}R(f *codecFnInfo, rv reflect.Value) {
if rv.Kind() == reflect.Ptr {
vp := rv2i(rv).(*map[{{ .MapKey }}]{{ .Elem }})
v, changed := fastpathTV.{{ .MethodNamePfx "Dec" false }}V(*vp, true, d);
if changed { *vp = v }
} else {
fastpathTV.{{ .MethodNamePfx "Dec" false }}V(rv2i(rv).(map[{{ .MapKey }}]{{ .Elem }}), false, d)
}
}
func (f fastpathT) {{ .MethodNamePfx "Dec" false }}X(vp *map[{{ .MapKey }}]{{ .Elem }}, d *Decoder) {
v, changed := f.{{ .MethodNamePfx "Dec" false }}V(*vp, true, d)
if changed { *vp = v }
}
func (_ fastpathT) {{ .MethodNamePfx "Dec" false }}V(v map[{{ .MapKey }}]{{ .Elem }}, canChange bool,
d *Decoder) (_ map[{{ .MapKey }}]{{ .Elem }}, changed bool) {
dd, esep := d.d, d.hh.hasElemSeparators(){{/*
// if dd.isContainerType(valueTypeNil) {dd.TryDecodeAsNil()
*/}}
containerLen := dd.ReadMapStart()
if canChange && v == nil {
xlen := decInferLen(containerLen, d.h.MaxInitLen, {{ .Size }})
v = make(map[{{ .MapKey }}]{{ .Elem }}, xlen)
changed = true
}
if containerLen == 0 {
dd.ReadMapEnd()
return v, changed
}
{{ if eq .Elem "interface{}" }}mapGet := v != nil && !d.h.MapValueReset && !d.h.InterfaceReset
{{end}}var mk {{ .MapKey }}
var mv {{ .Elem }}
hasLen := containerLen > 0
for j := 0; (hasLen && j < containerLen) || !(hasLen || dd.CheckBreak()); j++ {
if esep { dd.ReadMapElemKey() }
{{ if eq .MapKey "interface{}" }}mk = nil
d.decode(&mk)
if bv, bok := mk.([]byte); bok {
mk = d.string(bv) {{/* // maps cannot have []byte as key. switch to string. */}}
}{{ else }}mk = {{ decmd .MapKey }}{{ end }}
if esep { dd.ReadMapElemValue() }
if dd.TryDecodeAsNil() {
if v == nil {} else if d.h.DeleteOnNilMapValue { delete(v, mk) } else { v[mk] = {{ zerocmd .Elem }} }
continue
}
{{ if eq .Elem "interface{}" }}if mapGet { mv = v[mk] } else { mv = nil }
d.decode(&mv){{ else }}mv = {{ decmd .Elem }}{{ end }}
if v != nil { v[mk] = mv }
}
dd.ReadMapEnd()
return v, changed
}
{{end}}{{end}}{{end}}