gtsocial-umbx

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stackmap.go (3914B)

      1 /**
      2  * Copyright 2023 ByteDance Inc.
      3  *
      4  * Licensed under the Apache License, Version 2.0 (the "License");
      5  * you may not use this file except in compliance with the License.
      6  * You may obtain a copy of the License at
      7  *
      8  *     http://www.apache.org/licenses/LICENSE-2.0
      9  *
     10  * Unless required by applicable law or agreed to in writing, software
     11  * distributed under the License is distributed on an "AS IS" BASIS,
     12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
     13  * See the License for the specific language governing permissions and
     14  * limitations under the License.
     15  */
     16 
     17 package rt
     18 
     19 import (
     20     `fmt`
     21     `strings`
     22     `unsafe`
     23 
     24 )
     25 
     26 type Bitmap struct {
     27     N int
     28     B []byte
     29 }
     30 
     31 func (self *Bitmap) grow() {
     32     if self.N >= len(self.B) * 8 {
     33         self.B = append(self.B, 0)
     34     }
     35 }
     36 
     37 func (self *Bitmap) mark(i int, bv int) {
     38     if bv != 0 {
     39         self.B[i / 8] |= 1 << (i % 8)
     40     } else {
     41         self.B[i / 8] &^= 1 << (i % 8)
     42     }
     43 }
     44 
     45 func (self *Bitmap) Set(i int, bv int) {
     46     if i >= self.N {
     47         panic("bitmap: invalid bit position")
     48     } else {
     49         self.mark(i, bv)
     50     }
     51 }
     52 
     53 func (self *Bitmap) Append(bv int) {
     54     self.grow()
     55     self.mark(self.N, bv)
     56     self.N++
     57 }
     58 
     59 func (self *Bitmap) AppendMany(n int, bv int) {
     60     for i := 0; i < n; i++ {
     61         self.Append(bv)
     62     }
     63 }
     64 
     65 // var (
     66 //     _stackMapLock  = sync.Mutex{}
     67 //     _stackMapCache = make(map[*StackMap]struct{})
     68 // )
     69 
     70 type BitVec struct {
     71     N uintptr
     72     B unsafe.Pointer
     73 }
     74 
     75 func (self BitVec) Bit(i uintptr) byte {
     76     return (*(*byte)(unsafe.Pointer(uintptr(self.B) + i / 8)) >> (i % 8)) & 1
     77 }
     78 
     79 func (self BitVec) String() string {
     80     var i uintptr
     81     var v []string
     82 
     83     /* add each bit */
     84     for i = 0; i < self.N; i++ {
     85         v = append(v, fmt.Sprintf("%d", self.Bit(i)))
     86     }
     87 
     88     /* join them together */
     89     return fmt.Sprintf(
     90         "BitVec { %s }",
     91         strings.Join(v, ", "),
     92     )
     93 }
     94 
     95 type StackMap struct {
     96     N int32
     97     L int32
     98     B [1]byte
     99 }
    100 
    101 // func (self *StackMap) add() {
    102 //     _stackMapLock.Lock()
    103 //     _stackMapCache[self] = struct{}{}
    104 //     _stackMapLock.Unlock()
    105 // }
    106 
    107 func (self *StackMap) Pin() uintptr {
    108     // self.add()
    109     return uintptr(unsafe.Pointer(self))
    110 }
    111 
    112 func (self *StackMap) Get(i int32) BitVec {
    113     return BitVec {
    114         N: uintptr(self.L),
    115         B: unsafe.Pointer(uintptr(unsafe.Pointer(&self.B)) + uintptr(i * ((self.L + 7) >> 3))),
    116     }
    117 }
    118 
    119 func (self *StackMap) String() string {
    120     sb := strings.Builder{}
    121     sb.WriteString("StackMap {")
    122 
    123     /* dump every stack map */
    124     for i := int32(0); i < self.N; i++ {
    125         sb.WriteRune('\n')
    126         sb.WriteString("    " + self.Get(i).String())
    127     }
    128 
    129     /* close the stackmap */
    130     sb.WriteString("\n}")
    131     return sb.String()
    132 }
    133 
    134 func (self *StackMap) MarshalBinary() ([]byte, error) {
    135     size := int(self.N) * int(self.L) + int(unsafe.Sizeof(self.L)) + int(unsafe.Sizeof(self.N))
    136     return BytesFrom(unsafe.Pointer(self), size, size), nil
    137 }
    138 
    139 var (
    140     byteType = UnpackEface(byte(0)).Type
    141 )
    142 
    143 const (
    144     _StackMapSize = unsafe.Sizeof(StackMap{})
    145 )
    146 
    147 //go:linkname mallocgc runtime.mallocgc
    148 //goland:noinspection GoUnusedParameter
    149 func mallocgc(nb uintptr, vt *GoType, zero bool) unsafe.Pointer
    150 
    151 type StackMapBuilder struct {
    152     b Bitmap
    153 }
    154 
    155 //go:nocheckptr
    156 func (self *StackMapBuilder) Build() (p *StackMap) {
    157     nb := len(self.b.B)
    158     bm := mallocgc(_StackMapSize + uintptr(nb) - 1, byteType, false)
    159 
    160     /* initialize as 1 bitmap of N bits */
    161     p = (*StackMap)(bm)
    162     p.N, p.L = 1, int32(self.b.N)
    163     copy(BytesFrom(unsafe.Pointer(&p.B), nb, nb), self.b.B)
    164     return
    165 }
    166 
    167 func (self *StackMapBuilder) AddField(ptr bool) {
    168     if ptr {
    169         self.b.Append(1)
    170     } else {
    171         self.b.Append(0)
    172     }
    173 }
    174 
    175 func (self *StackMapBuilder) AddFields(n int, ptr bool) {
    176     if ptr {
    177         self.b.AppendMany(n, 1)
    178     } else {
    179         self.b.AppendMany(n, 0)
    180     }
    181 }