photoprism-client-go/vendor/github.com/ugorji/go/codec/helper_unsafe.go

1023 lines
28 KiB
Go

// +build !safe
// +build !appengine
// +build go1.8
// Copyright (c) 2012-2020 Ugorji Nwoke. All rights reserved.
// Use of this source code is governed by a MIT license found in the LICENSE file.
// go 1.8 is needed, as that is when all linknames exist.
// specifically, typedmemclr was introduced in go 1.8
package codec
import (
"reflect"
_ "runtime" // needed so that gccgo works with go linkname(s)
"sync/atomic"
"time"
"unsafe"
)
// This file has unsafe variants of some helper methods.
// MARKER: See helper_not_unsafe.go for the usage information.
// For reflect.Value code, we decided to do the following:
// - if we know the kind, we can elide conditional checks for
// - SetXXX (Int, Uint, String, Bool, etc)
// - SetLen
//
// We can also optimize
// - IsNil
const safeMode = false
// helperUnsafeCopyMapEntry says that we should copy the pointer in the map
// to another value during mapRange/iteration and mapGet calls.
//
// The only callers of mapRange/iteration is encode.
// Here, we just walk through the values and encode them
//
// The only caller of mapGet is decode.
// Here, it does a Get if the underlying value is a pointer, and decodes into that.
//
// For both users, we are very careful NOT to modify or keep the pointers around.
// Consequently, it is ok for take advantage of the performance that the map is not modified
// during an iteration and we can just "peek" at the internal value" in the map and use it.
const helperUnsafeCopyMapEntry = false
// MARKER: keep in sync with GO_ROOT/src/reflect/value.go
const (
unsafeFlagStickyRO = 1 << 5
unsafeFlagEmbedRO = 1 << 6
unsafeFlagIndir = 1 << 7
unsafeFlagAddr = 1 << 8
unsafeFlagKindMask = (1 << 5) - 1 // 5 bits for 27 kinds (up to 31)
// unsafeTypeKindDirectIface = 1 << 5
)
type unsafeString struct {
Data unsafe.Pointer
Len int
}
type unsafeSlice struct {
Data unsafe.Pointer
Len int
Cap int
}
type unsafeIntf struct {
typ unsafe.Pointer
word unsafe.Pointer
}
type unsafeReflectValue struct {
typ unsafe.Pointer
ptr unsafe.Pointer
flag uintptr
}
var unsafeZeroSlice = unsafeSlice{unsafe.Pointer(&unsafeZeroArr[0]), 0, 0}
func stringView(v []byte) string {
return *(*string)(unsafe.Pointer(&v))
}
func bytesView(v string) (b []byte) {
sx := (*unsafeString)(unsafe.Pointer(&v))
bx := (*unsafeSlice)(unsafe.Pointer(&b))
bx.Data, bx.Len, bx.Cap = sx.Data, sx.Len, sx.Len
return
}
func isNil(v interface{}) (rv reflect.Value, isnil bool) {
var ui = (*unsafeIntf)(unsafe.Pointer(&v))
if ui.word == nil {
isnil = true
return
}
rv = rv4i(v) // reflect.value is cheap and inline'able
tk := rv.Kind()
isnil = (tk == reflect.Interface || tk == reflect.Slice) && *(*unsafe.Pointer)(ui.word) == nil
return
}
// return the pointer for a reference (map/chan/func/pointer/unsafe.Pointer).
// true references (map, func, chan, ptr - NOT slice) may be double-referenced? as flagIndir
func rvRefPtr(v *unsafeReflectValue) unsafe.Pointer {
if v.flag&unsafeFlagIndir != 0 {
return *(*unsafe.Pointer)(v.ptr)
}
return v.ptr
}
func rv2ptr(urv *unsafeReflectValue) unsafe.Pointer {
if refBitset.isset(byte(urv.flag&unsafeFlagKindMask)) && urv.flag&unsafeFlagIndir != 0 {
return *(*unsafe.Pointer)(urv.ptr)
}
return urv.ptr
}
// func rvAddr(rv reflect.Value) uintptr {
// return uintptr((*unsafeReflectValue)(unsafe.Pointer(&rv)).ptr)
// }
func eq4i(i0, i1 interface{}) bool {
v0 := (*unsafeIntf)(unsafe.Pointer(&i0))
v1 := (*unsafeIntf)(unsafe.Pointer(&i1))
return v0.typ == v1.typ && v0.word == v1.word
}
func rv4i(i interface{}) (rv reflect.Value) {
// Unfortunately, we cannot get the "kind" of the interface directly here.
// We need the 'rtype', whose structure changes in different go versions.
// Finally, it's not clear that there is benefit to reimplementing it,
// as the "escapes(i)" is not clearly expensive since we want i to exist on the heap.
return reflect.ValueOf(i)
}
func rv2i(rv reflect.Value) interface{} {
// We tap into implememtation details from
// the source go stdlib reflect/value.go, and trims the implementation.
urv := (*unsafeReflectValue)(unsafe.Pointer(&rv))
return *(*interface{})(unsafe.Pointer(&unsafeIntf{typ: urv.typ, word: rv2ptr(urv)}))
}
func rvIsNil(rv reflect.Value) bool {
urv := (*unsafeReflectValue)(unsafe.Pointer(&rv))
if urv.flag&unsafeFlagIndir != 0 {
return *(*unsafe.Pointer)(urv.ptr) == nil
}
return urv.ptr == nil
}
func rvSetSliceLen(rv reflect.Value, length int) {
urv := (*unsafeReflectValue)(unsafe.Pointer(&rv))
(*unsafeString)(urv.ptr).Len = length
}
func rvZeroAddrK(t reflect.Type, k reflect.Kind) (rv reflect.Value) {
urv := (*unsafeReflectValue)(unsafe.Pointer(&rv))
urv.flag = uintptr(k) | unsafeFlagIndir | unsafeFlagAddr
urv.typ = ((*unsafeIntf)(unsafe.Pointer(&t))).word
urv.ptr = unsafe_New(urv.typ)
return
}
func rvZeroAddr(t reflect.Type) reflect.Value {
return rvZeroAddrK(t, t.Kind())
}
func rvZeroK(t reflect.Type, k reflect.Kind) (rv reflect.Value) {
urv := (*unsafeReflectValue)(unsafe.Pointer(&rv))
urv.typ = ((*unsafeIntf)(unsafe.Pointer(&t))).word
if refBitset.isset(byte(k)) {
urv.flag = uintptr(k)
} else if (k == reflect.Struct || k == reflect.Array) && t.Size() > uintptr(len(unsafeZeroArr)) {
urv.flag = uintptr(k) | unsafeFlagIndir | unsafeFlagAddr
urv.ptr = unsafe_New(urv.typ)
} else {
urv.flag = uintptr(k) | unsafeFlagIndir
urv.ptr = unsafe.Pointer(&unsafeZeroArr[0])
}
return
}
func rvZero(t reflect.Type) reflect.Value {
return rvZeroK(t, t.Kind())
}
func rvConvert(v reflect.Value, t reflect.Type) (rv reflect.Value) {
uv := (*unsafeReflectValue)(unsafe.Pointer(&v))
urv := (*unsafeReflectValue)(unsafe.Pointer(&rv))
*urv = *uv
urv.typ = ((*unsafeIntf)(unsafe.Pointer(&t))).word
return
}
func rt2id(rt reflect.Type) uintptr {
return uintptr(((*unsafeIntf)(unsafe.Pointer(&rt))).word)
}
func i2rtid(i interface{}) uintptr {
return uintptr(((*unsafeIntf)(unsafe.Pointer(&i))).typ)
}
// --------------------------
func unsafeCmpZero(ptr unsafe.Pointer, size int) bool {
var s1, s2 string
s1u := (*unsafeString)(unsafe.Pointer(&s1))
s2u := (*unsafeString)(unsafe.Pointer(&s2))
s1u.Data, s1u.Len, s2u.Len = ptr, size, size
if size <= len(unsafeZeroArr) {
s2u.Data = unsafe.Pointer(&unsafeZeroArr[0])
} else {
arr := make([]byte, size)
s2u.Data = unsafe.Pointer(&arr[0])
}
return s1 == s2 // memcmp
}
func isEmptyValue(v reflect.Value, tinfos *TypeInfos, recursive bool) bool {
urv := (*unsafeReflectValue)(unsafe.Pointer(&v))
if urv.flag == 0 {
return true
}
if recursive {
return isEmptyValueFallbackRecur(urv, v, tinfos)
}
// t := rvPtrToType(urv.typ)
// // it is empty if it is a zero value OR it points to a zero value
// if urv.flag&unsafeFlagIndir == 0 { // this is a pointer
// if urv.ptr == nil {
// return true
// }
// return unsafeCmpZero(*(*unsafe.Pointer)(urv.ptr), int(t.Elem().Size()))
// }
// return unsafeCmpZero(urv.ptr, int(t.Size()))
// return unsafeCmpZero(urv.ptr, int(rvPtrToType(urv.typ).Size()))
return unsafeCmpZero(urv.ptr, int(rvType(v).Size()))
}
func isEmptyValueFallbackRecur(urv *unsafeReflectValue, v reflect.Value, tinfos *TypeInfos) bool {
const recursive = true
switch v.Kind() {
case reflect.Invalid:
return true
case reflect.String:
return (*unsafeString)(urv.ptr).Len == 0
case reflect.Slice:
return (*unsafeSlice)(urv.ptr).Len == 0
case reflect.Bool:
return !*(*bool)(urv.ptr)
case reflect.Int:
return *(*int)(urv.ptr) == 0
case reflect.Int8:
return *(*int8)(urv.ptr) == 0
case reflect.Int16:
return *(*int16)(urv.ptr) == 0
case reflect.Int32:
return *(*int32)(urv.ptr) == 0
case reflect.Int64:
return *(*int64)(urv.ptr) == 0
case reflect.Uint:
return *(*uint)(urv.ptr) == 0
case reflect.Uint8:
return *(*uint8)(urv.ptr) == 0
case reflect.Uint16:
return *(*uint16)(urv.ptr) == 0
case reflect.Uint32:
return *(*uint32)(urv.ptr) == 0
case reflect.Uint64:
return *(*uint64)(urv.ptr) == 0
case reflect.Uintptr:
return *(*uintptr)(urv.ptr) == 0
case reflect.Float32:
return *(*float32)(urv.ptr) == 0
case reflect.Float64:
return *(*float64)(urv.ptr) == 0
case reflect.Complex64:
return unsafeCmpZero(urv.ptr, 8)
case reflect.Complex128:
return unsafeCmpZero(urv.ptr, 16)
case reflect.Struct:
return isEmptyStruct(v, tinfos, recursive)
case reflect.Interface, reflect.Ptr:
// isnil := urv.ptr == nil // (not sufficient, as a pointer value encodes the type)
isnil := urv.ptr == nil || *(*unsafe.Pointer)(urv.ptr) == nil
if recursive && !isnil {
return isEmptyValue(v.Elem(), tinfos, recursive)
}
return isnil
case reflect.UnsafePointer:
return urv.ptr == nil || *(*unsafe.Pointer)(urv.ptr) == nil
case reflect.Chan:
return urv.ptr == nil || chanlen(rvRefPtr(urv)) == 0
case reflect.Map:
return urv.ptr == nil || maplen(rvRefPtr(urv)) == 0
case reflect.Array:
return rvLenArray(v) == 0
}
return false
}
// --------------------------
// atomicXXX is expected to be 2 words (for symmetry with atomic.Value)
//
// Note that we do not atomically load/store length and data pointer separately,
// as this could lead to some races. Instead, we atomically load/store cappedSlice.
//
// Note: with atomic.(Load|Store)Pointer, we MUST work with an unsafe.Pointer directly.
// ----------------------
type atomicTypeInfoSlice struct {
v unsafe.Pointer // *[]rtid2ti
// _ uint64 // padding (atomicXXX expected to be 2 words)
}
func (x *atomicTypeInfoSlice) load() (s []rtid2ti) {
x2 := atomic.LoadPointer(&x.v)
if x2 != nil {
s = *(*[]rtid2ti)(x2)
}
return
}
func (x *atomicTypeInfoSlice) store(p []rtid2ti) {
atomic.StorePointer(&x.v, unsafe.Pointer(&p))
}
// MARKER: in safe mode, atomicXXX are atomic.Value, which contains an interface{}.
// This is 2 words.
// consider padding atomicXXX here with a uintptr, so they fit into 2 words also.
// --------------------------
type atomicRtidFnSlice struct {
v unsafe.Pointer // *[]codecRtidFn
}
func (x *atomicRtidFnSlice) load() (s []codecRtidFn) {
x2 := atomic.LoadPointer(&x.v)
if x2 != nil {
s = *(*[]codecRtidFn)(x2)
}
return
}
func (x *atomicRtidFnSlice) store(p []codecRtidFn) {
atomic.StorePointer(&x.v, unsafe.Pointer(&p))
}
// --------------------------
type atomicClsErr struct {
v unsafe.Pointer // *clsErr
}
func (x *atomicClsErr) load() (e clsErr) {
x2 := (*clsErr)(atomic.LoadPointer(&x.v))
if x2 != nil {
e = *x2
}
return
}
func (x *atomicClsErr) store(p clsErr) {
atomic.StorePointer(&x.v, unsafe.Pointer(&p))
}
// --------------------------
// to create a reflect.Value for each member field of fauxUnion,
// we first create a global fauxUnion, and create reflect.Value
// for them all.
// This way, we have the flags and type in the reflect.Value.
// Then, when a reflect.Value is called, we just copy it,
// update the ptr to the fauxUnion's, and return it.
type unsafeDecNakedWrapper struct {
fauxUnion
ru, ri, rf, rl, rs, rb, rt reflect.Value // mapping to the primitives above
}
func (n *unsafeDecNakedWrapper) init() {
n.ru = rv4i(&n.u).Elem()
n.ri = rv4i(&n.i).Elem()
n.rf = rv4i(&n.f).Elem()
n.rl = rv4i(&n.l).Elem()
n.rs = rv4i(&n.s).Elem()
n.rt = rv4i(&n.t).Elem()
n.rb = rv4i(&n.b).Elem()
// n.rr[] = rv4i(&n.)
}
var defUnsafeDecNakedWrapper unsafeDecNakedWrapper
func init() {
defUnsafeDecNakedWrapper.init()
}
func (n *fauxUnion) ru() (v reflect.Value) {
v = defUnsafeDecNakedWrapper.ru
((*unsafeReflectValue)(unsafe.Pointer(&v))).ptr = unsafe.Pointer(&n.u)
return
}
func (n *fauxUnion) ri() (v reflect.Value) {
v = defUnsafeDecNakedWrapper.ri
((*unsafeReflectValue)(unsafe.Pointer(&v))).ptr = unsafe.Pointer(&n.i)
return
}
func (n *fauxUnion) rf() (v reflect.Value) {
v = defUnsafeDecNakedWrapper.rf
((*unsafeReflectValue)(unsafe.Pointer(&v))).ptr = unsafe.Pointer(&n.f)
return
}
func (n *fauxUnion) rl() (v reflect.Value) {
v = defUnsafeDecNakedWrapper.rl
((*unsafeReflectValue)(unsafe.Pointer(&v))).ptr = unsafe.Pointer(&n.l)
return
}
func (n *fauxUnion) rs() (v reflect.Value) {
v = defUnsafeDecNakedWrapper.rs
((*unsafeReflectValue)(unsafe.Pointer(&v))).ptr = unsafe.Pointer(&n.s)
return
}
func (n *fauxUnion) rt() (v reflect.Value) {
v = defUnsafeDecNakedWrapper.rt
((*unsafeReflectValue)(unsafe.Pointer(&v))).ptr = unsafe.Pointer(&n.t)
return
}
func (n *fauxUnion) rb() (v reflect.Value) {
v = defUnsafeDecNakedWrapper.rb
((*unsafeReflectValue)(unsafe.Pointer(&v))).ptr = unsafe.Pointer(&n.b)
return
}
// --------------------------
func rvSetBytes(rv reflect.Value, v []byte) {
urv := (*unsafeReflectValue)(unsafe.Pointer(&rv))
*(*[]byte)(urv.ptr) = v
}
func rvSetString(rv reflect.Value, v string) {
urv := (*unsafeReflectValue)(unsafe.Pointer(&rv))
*(*string)(urv.ptr) = v
}
func rvSetBool(rv reflect.Value, v bool) {
urv := (*unsafeReflectValue)(unsafe.Pointer(&rv))
*(*bool)(urv.ptr) = v
}
func rvSetTime(rv reflect.Value, v time.Time) {
urv := (*unsafeReflectValue)(unsafe.Pointer(&rv))
*(*time.Time)(urv.ptr) = v
}
func rvSetFloat32(rv reflect.Value, v float32) {
urv := (*unsafeReflectValue)(unsafe.Pointer(&rv))
*(*float32)(urv.ptr) = v
}
func rvSetFloat64(rv reflect.Value, v float64) {
urv := (*unsafeReflectValue)(unsafe.Pointer(&rv))
*(*float64)(urv.ptr) = v
}
func rvSetInt(rv reflect.Value, v int) {
urv := (*unsafeReflectValue)(unsafe.Pointer(&rv))
*(*int)(urv.ptr) = v
}
func rvSetInt8(rv reflect.Value, v int8) {
urv := (*unsafeReflectValue)(unsafe.Pointer(&rv))
*(*int8)(urv.ptr) = v
}
func rvSetInt16(rv reflect.Value, v int16) {
urv := (*unsafeReflectValue)(unsafe.Pointer(&rv))
*(*int16)(urv.ptr) = v
}
func rvSetInt32(rv reflect.Value, v int32) {
urv := (*unsafeReflectValue)(unsafe.Pointer(&rv))
*(*int32)(urv.ptr) = v
}
func rvSetInt64(rv reflect.Value, v int64) {
urv := (*unsafeReflectValue)(unsafe.Pointer(&rv))
*(*int64)(urv.ptr) = v
}
func rvSetUint(rv reflect.Value, v uint) {
urv := (*unsafeReflectValue)(unsafe.Pointer(&rv))
*(*uint)(urv.ptr) = v
}
func rvSetUintptr(rv reflect.Value, v uintptr) {
urv := (*unsafeReflectValue)(unsafe.Pointer(&rv))
*(*uintptr)(urv.ptr) = v
}
func rvSetUint8(rv reflect.Value, v uint8) {
urv := (*unsafeReflectValue)(unsafe.Pointer(&rv))
*(*uint8)(urv.ptr) = v
}
func rvSetUint16(rv reflect.Value, v uint16) {
urv := (*unsafeReflectValue)(unsafe.Pointer(&rv))
*(*uint16)(urv.ptr) = v
}
func rvSetUint32(rv reflect.Value, v uint32) {
urv := (*unsafeReflectValue)(unsafe.Pointer(&rv))
*(*uint32)(urv.ptr) = v
}
func rvSetUint64(rv reflect.Value, v uint64) {
urv := (*unsafeReflectValue)(unsafe.Pointer(&rv))
*(*uint64)(urv.ptr) = v
}
// ----------------
// rvSetDirect is rv.Set for all kinds except reflect.Interface
func rvSetDirect(rv reflect.Value, v reflect.Value) {
urv := (*unsafeReflectValue)(unsafe.Pointer(&rv))
uv := (*unsafeReflectValue)(unsafe.Pointer(&v))
if uv.flag&unsafeFlagIndir == 0 {
*(*unsafe.Pointer)(urv.ptr) = uv.ptr
} else if uv.ptr == unsafe.Pointer(&unsafeZeroArr[0]) {
typedmemclr(urv.typ, urv.ptr)
} else {
typedmemmove(urv.typ, urv.ptr, uv.ptr)
}
}
func rvSetDirectZero(rv reflect.Value) {
urv := (*unsafeReflectValue)(unsafe.Pointer(&rv))
typedmemclr(urv.typ, urv.ptr)
}
// rvSlice returns a slice of the slice of lenth
func rvSlice(rv reflect.Value, length int) (v reflect.Value) {
urv := (*unsafeReflectValue)(unsafe.Pointer(&rv))
uv := (*unsafeReflectValue)(unsafe.Pointer(&v))
*uv = *urv
var x []unsafe.Pointer
uv.ptr = unsafe.Pointer(&x)
*(*unsafeSlice)(uv.ptr) = *(*unsafeSlice)(urv.ptr)
(*unsafeSlice)(uv.ptr).Len = length
return
}
// ------------
func rvSliceIndex(rv reflect.Value, i int, ti *typeInfo) (v reflect.Value) {
urv := (*unsafeReflectValue)(unsafe.Pointer(&rv))
uv := (*unsafeReflectValue)(unsafe.Pointer(&v))
uv.ptr = unsafe.Pointer(uintptr(((*unsafeSlice)(urv.ptr)).Data) + uintptr(int(ti.elemsize)*i))
uv.typ = ((*unsafeIntf)(unsafe.Pointer(&ti.elem))).word
uv.flag = uintptr(ti.elemkind) | unsafeFlagIndir | unsafeFlagAddr
return
}
func rvSliceZeroCap(t reflect.Type) (v reflect.Value) {
urv := (*unsafeReflectValue)(unsafe.Pointer(&v))
urv.typ = ((*unsafeIntf)(unsafe.Pointer(&t))).word
urv.flag = uintptr(reflect.Slice) | unsafeFlagIndir
urv.ptr = unsafe.Pointer(&unsafeZeroSlice)
return
}
func rvLenSlice(rv reflect.Value) int {
urv := (*unsafeReflectValue)(unsafe.Pointer(&rv))
return (*unsafeSlice)(urv.ptr).Len
}
func rvCapSlice(rv reflect.Value) int {
urv := (*unsafeReflectValue)(unsafe.Pointer(&rv))
return (*unsafeSlice)(urv.ptr).Cap
}
func rvGetArrayBytesRO(rv reflect.Value, scratch []byte) (bs []byte) {
urv := (*unsafeReflectValue)(unsafe.Pointer(&rv))
bx := (*unsafeSlice)(unsafe.Pointer(&bs))
bx.Data = urv.ptr
bx.Len = rvLenArray(rv)
bx.Cap = bx.Len
return
}
func rvGetArray4Slice(rv reflect.Value) (v reflect.Value) {
// It is possible that this slice is based off an array with a larger
// len that we want (where array len == slice cap).
// However, it is ok to create an array type that is a subset of the full
// e.g. full slice is based off a *[16]byte, but we can create a *[4]byte
// off of it. That is ok.
//
// Consequently, we use rvLenSlice, not rvCapSlice.
t := reflectArrayOf(rvLenSlice(rv), rvType(rv).Elem())
// v = rvZeroAddrK(t, reflect.Array)
uv := (*unsafeReflectValue)(unsafe.Pointer(&v))
uv.flag = uintptr(reflect.Array) | unsafeFlagIndir | unsafeFlagAddr
uv.typ = ((*unsafeIntf)(unsafe.Pointer(&t))).word
urv := (*unsafeReflectValue)(unsafe.Pointer(&rv))
uv.ptr = *(*unsafe.Pointer)(urv.ptr) // slice rv has a ptr to the slice.
return
}
func rvGetSlice4Array(rv reflect.Value, tslice reflect.Type) (v reflect.Value) {
uv := (*unsafeReflectValue)(unsafe.Pointer(&v))
urv := (*unsafeReflectValue)(unsafe.Pointer(&rv))
var x []unsafe.Pointer
uv.ptr = unsafe.Pointer(&x)
uv.typ = ((*unsafeIntf)(unsafe.Pointer(&tslice))).word
uv.flag = unsafeFlagIndir | uintptr(reflect.Slice)
s := (*unsafeSlice)(uv.ptr)
s.Data = urv.ptr
s.Len = rvLenArray(rv)
s.Cap = s.Len
return
}
func rvCopySlice(dest, src reflect.Value) {
t := rvType(dest).Elem()
urv := (*unsafeReflectValue)(unsafe.Pointer(&dest))
destPtr := urv.ptr
urv = (*unsafeReflectValue)(unsafe.Pointer(&src))
typedslicecopy((*unsafeIntf)(unsafe.Pointer(&t)).word,
*(*unsafeSlice)(destPtr), *(*unsafeSlice)(urv.ptr))
}
// ------------
func rvGetBool(rv reflect.Value) bool {
v := (*unsafeReflectValue)(unsafe.Pointer(&rv))
return *(*bool)(v.ptr)
}
func rvGetBytes(rv reflect.Value) []byte {
v := (*unsafeReflectValue)(unsafe.Pointer(&rv))
return *(*[]byte)(v.ptr)
}
func rvGetTime(rv reflect.Value) time.Time {
v := (*unsafeReflectValue)(unsafe.Pointer(&rv))
return *(*time.Time)(v.ptr)
}
func rvGetString(rv reflect.Value) string {
v := (*unsafeReflectValue)(unsafe.Pointer(&rv))
return *(*string)(v.ptr)
}
func rvGetFloat64(rv reflect.Value) float64 {
v := (*unsafeReflectValue)(unsafe.Pointer(&rv))
return *(*float64)(v.ptr)
}
func rvGetFloat32(rv reflect.Value) float32 {
v := (*unsafeReflectValue)(unsafe.Pointer(&rv))
return *(*float32)(v.ptr)
}
func rvGetInt(rv reflect.Value) int {
v := (*unsafeReflectValue)(unsafe.Pointer(&rv))
return *(*int)(v.ptr)
}
func rvGetInt8(rv reflect.Value) int8 {
v := (*unsafeReflectValue)(unsafe.Pointer(&rv))
return *(*int8)(v.ptr)
}
func rvGetInt16(rv reflect.Value) int16 {
v := (*unsafeReflectValue)(unsafe.Pointer(&rv))
return *(*int16)(v.ptr)
}
func rvGetInt32(rv reflect.Value) int32 {
v := (*unsafeReflectValue)(unsafe.Pointer(&rv))
return *(*int32)(v.ptr)
}
func rvGetInt64(rv reflect.Value) int64 {
v := (*unsafeReflectValue)(unsafe.Pointer(&rv))
return *(*int64)(v.ptr)
}
func rvGetUint(rv reflect.Value) uint {
v := (*unsafeReflectValue)(unsafe.Pointer(&rv))
return *(*uint)(v.ptr)
}
func rvGetUint8(rv reflect.Value) uint8 {
v := (*unsafeReflectValue)(unsafe.Pointer(&rv))
return *(*uint8)(v.ptr)
}
func rvGetUint16(rv reflect.Value) uint16 {
v := (*unsafeReflectValue)(unsafe.Pointer(&rv))
return *(*uint16)(v.ptr)
}
func rvGetUint32(rv reflect.Value) uint32 {
v := (*unsafeReflectValue)(unsafe.Pointer(&rv))
return *(*uint32)(v.ptr)
}
func rvGetUint64(rv reflect.Value) uint64 {
v := (*unsafeReflectValue)(unsafe.Pointer(&rv))
return *(*uint64)(v.ptr)
}
func rvGetUintptr(rv reflect.Value) uintptr {
v := (*unsafeReflectValue)(unsafe.Pointer(&rv))
return *(*uintptr)(v.ptr)
}
func rvLenMap(rv reflect.Value) int {
v := (*unsafeReflectValue)(unsafe.Pointer(&rv))
return maplen(rvRefPtr(v))
}
func rvLenArray(rv reflect.Value) int {
return rv.Len()
}
// ------------ map range and map indexing ----------
// regular calls to map via reflection: MapKeys, MapIndex, MapRange/MapIter etc
// will always allocate for each map key or value.
//
// It is more performant to provide a value that the map entry is set into,
// and that elides the allocation.
// unsafeMapHashIter
//
// go 1.4+ has runtime/hashmap.go or runtime/map.go which has a
// hIter struct with the first 2 values being key and value
// of the current iteration.
//
// This *hIter is passed to mapiterinit, mapiternext, mapiterkey, mapiterelem.
// We bypass the reflect wrapper functions and just use the *hIter directly.
//
// Though *hIter has many fields, we only care about the first 2.
type unsafeMapHashIter struct {
key, value unsafe.Pointer
// other fields are ignored
}
type mapIter struct {
unsafeMapIter
}
type unsafeMapIter struct {
it *unsafeMapHashIter
mtyp, mptr unsafe.Pointer
k, v reflect.Value
kisref, visref bool
mapvalues bool
done bool
started bool
}
func (t *unsafeMapIter) Next() (r bool) {
if t == nil || t.done {
return
}
if t.started {
mapiternext((unsafe.Pointer)(t.it))
} else {
t.started = true
}
t.done = t.it.key == nil
if t.done {
return
}
if helperUnsafeCopyMapEntry {
k := (*unsafeReflectValue)(unsafe.Pointer(&t.k))
unsafeMapSet(k.typ, k.ptr, t.it.key, t.kisref)
if t.mapvalues {
v := (*unsafeReflectValue)(unsafe.Pointer(&t.v))
unsafeMapSet(v.typ, v.ptr, t.it.value, t.visref)
}
} else {
(*unsafeReflectValue)(unsafe.Pointer(&t.k)).ptr = t.it.key
if t.mapvalues {
(*unsafeReflectValue)(unsafe.Pointer(&t.v)).ptr = t.it.value
}
}
return true
}
func (t *unsafeMapIter) Key() (r reflect.Value) {
return t.k
}
func (t *unsafeMapIter) Value() (r reflect.Value) {
return t.v
}
func (t *unsafeMapIter) Done() {}
// unsafeMapSet does equivalent of: p = p2
func unsafeMapSet(ptyp, p, p2 unsafe.Pointer, isref bool) {
if isref {
*(*unsafe.Pointer)(p) = *(*unsafe.Pointer)(p2) // p2
} else {
typedmemmove(ptyp, p, p2) // *(*unsafe.Pointer)(p2)) // p2)
}
}
// unsafeMapKVPtr returns the pointer if flagIndir, else it returns a pointer to the pointer.
// It is needed as maps always keep a reference to the underlying value.
func unsafeMapKVPtr(urv *unsafeReflectValue) unsafe.Pointer {
if urv.flag&unsafeFlagIndir == 0 {
return unsafe.Pointer(&urv.ptr)
}
return urv.ptr
}
func mapRange(t *mapIter, m, k, v reflect.Value, mapvalues bool) {
if rvIsNil(m) {
t.done = true
return
}
t.done = false
t.started = false
t.mapvalues = mapvalues
// var urv *unsafeReflectValue
urv := (*unsafeReflectValue)(unsafe.Pointer(&m))
t.mtyp = urv.typ
t.mptr = rvRefPtr(urv)
t.it = (*unsafeMapHashIter)(mapiterinit(t.mtyp, t.mptr))
t.k = k
t.kisref = refBitset.isset(byte(k.Kind()))
if mapvalues {
t.v = v
t.visref = refBitset.isset(byte(v.Kind()))
} else {
t.v = reflect.Value{}
}
}
func mapGet(m, k, v reflect.Value) (vv reflect.Value) {
var urv = (*unsafeReflectValue)(unsafe.Pointer(&k))
var kptr = unsafeMapKVPtr(urv)
urv = (*unsafeReflectValue)(unsafe.Pointer(&m))
vvptr := mapaccess(urv.typ, rvRefPtr(urv), kptr)
if vvptr == nil {
return
}
// vvptr = *(*unsafe.Pointer)(vvptr)
urv = (*unsafeReflectValue)(unsafe.Pointer(&v))
if helperUnsafeCopyMapEntry {
unsafeMapSet(urv.typ, urv.ptr, vvptr, refBitset.isset(byte(v.Kind())))
} else {
urv.ptr = vvptr
}
return v
}
func mapSet(m, k, v reflect.Value) {
var urv = (*unsafeReflectValue)(unsafe.Pointer(&k))
var kptr = unsafeMapKVPtr(urv)
urv = (*unsafeReflectValue)(unsafe.Pointer(&v))
var vptr = unsafeMapKVPtr(urv)
urv = (*unsafeReflectValue)(unsafe.Pointer(&m))
mapassign(urv.typ, rvRefPtr(urv), kptr, vptr)
}
// func mapDelete(m, k reflect.Value) {
// var urv = (*unsafeReflectValue)(unsafe.Pointer(&k))
// var kptr = unsafeMapKVPtr(urv)
// urv = (*unsafeReflectValue)(unsafe.Pointer(&m))
// mapdelete(urv.typ, rv2ptr(urv), kptr)
// }
// return an addressable reflect value that can be used in mapRange and mapGet operations.
//
// all calls to mapGet or mapRange will call here to get an addressable reflect.Value.
func mapAddrLoopvarRV(t reflect.Type, k reflect.Kind) (r reflect.Value) {
return rvZeroAddrK(t, k)
}
// ---------- ENCODER optimized ---------------
func (e *Encoder) jsondriver() *jsonEncDriver {
return (*jsonEncDriver)((*unsafeIntf)(unsafe.Pointer(&e.e)).word)
}
// ---------- DECODER optimized ---------------
func (d *Decoder) checkBreak() bool {
// MARKER: jsonDecDriver.CheckBreak() costs over 80, and this isn't inlined.
// Consequently, there's no benefit in incurring the cost of this
// wrapping function checkBreak.
//
// It is faster to just call the interface method directly.
// if d.js {
// return d.jsondriver().CheckBreak()
// }
// if d.cbor {
// return d.cbordriver().CheckBreak()
// }
return d.d.CheckBreak()
}
func (d *Decoder) jsondriver() *jsonDecDriver {
return (*jsonDecDriver)((*unsafeIntf)(unsafe.Pointer(&d.d)).word)
}
// ---------- structFieldInfo optimized ---------------
func (n *structFieldInfoPathNode) rvField(v reflect.Value) (rv reflect.Value) {
// we already know this is exported, and maybe embedded (based on what si says)
uv := (*unsafeReflectValue)(unsafe.Pointer(&v))
urv := (*unsafeReflectValue)(unsafe.Pointer(&rv))
// clear flagEmbedRO if necessary, and inherit permission bits from v
urv.flag = uv.flag&(unsafeFlagStickyRO|unsafeFlagIndir|unsafeFlagAddr) | uintptr(n.kind)
urv.typ = ((*unsafeIntf)(unsafe.Pointer(&n.typ))).word
urv.ptr = unsafe.Pointer(uintptr(uv.ptr) + uintptr(n.offset))
return
}
// ---------- go linknames (LINKED to runtime/reflect) ---------------
// MARKER: always check that these linknames match subsequent versions of go
//
// Note that as of Jan 2021 (go 1.16 release), go:linkname(s) are not inlined
// outside of the standard library use (e.g. within sync, reflect, etc).
//
// Consequently, these do not necessarily give a performance boost, as a function overhead.
//
// Also, we link to the functions in reflect where possible, as opposed to those in runtime.
// They are guaranteed to be safer for our use, even when they are just trampoline functions.
//go:linkname maplen reflect.maplen
//go:noescape
func maplen(typ unsafe.Pointer) int
//go:linkname chanlen reflect.chanlen
//go:noescape
func chanlen(typ unsafe.Pointer) int
//go:linkname mapiterinit reflect.mapiterinit
//go:noescape
func mapiterinit(typ unsafe.Pointer, it unsafe.Pointer) (key unsafe.Pointer)
//go:linkname mapiternext reflect.mapiternext
//go:noescape
func mapiternext(it unsafe.Pointer) (key unsafe.Pointer)
//go:linkname mapaccess reflect.mapaccess
//go:noescape
func mapaccess(typ unsafe.Pointer, m unsafe.Pointer, key unsafe.Pointer) (val unsafe.Pointer)
//go:linkname mapassign reflect.mapassign
//go:noescape
func mapassign(typ unsafe.Pointer, m unsafe.Pointer, key, val unsafe.Pointer)
//go:linkname mapdelete reflect.mapdelete
//go:noescape
func mapdelete(typ unsafe.Pointer, m unsafe.Pointer, key unsafe.Pointer)
//go:linkname unsafe_New reflect.unsafe_New
//go:noescape
func unsafe_New(typ unsafe.Pointer) unsafe.Pointer
//go:linkname typedslicecopy reflect.typedslicecopy
//go:noescape
func typedslicecopy(elemType unsafe.Pointer, dst, src unsafeSlice) int
//go:linkname typedmemmove reflect.typedmemmove
//go:noescape
func typedmemmove(typ unsafe.Pointer, dst, src unsafe.Pointer)
//go:linkname typedmemclr reflect.typedmemclr
//go:noescape
func typedmemclr(typ unsafe.Pointer, dst unsafe.Pointer)
/*
//go:linkname memhash runtime.memhash
//go:noescape
func memhash(p unsafe.Pointer, seed, length uintptr) uintptr
// ---------- others ---------------
func hashShortString(b []byte) uintptr {
return memhash(unsafe.Pointer(&b[0]), 0, uintptr(len(b)))
}
// var _ = runtime.MemProfileRate
// func maplen(typ unsafe.Pointer) int { return *((*int)(typ)) }
// func chanlen(typ unsafe.Pointer) int { return int(*((*uint)(typ))) }
*/