mirror of
https://github.com/superseriousbusiness/gotosocial.git
synced 2024-12-23 18:52:11 +00:00
356 lines
12 KiB
Go
356 lines
12 KiB
Go
// go:build go1.18 && !go1.23
|
|
// +build go1.18,!go1.23
|
|
|
|
/*
|
|
* Copyright 2021 ByteDance Inc.
|
|
*
|
|
* Licensed under the Apache License, Version 2.0 (the "License");
|
|
* you may not use this file except in compliance with the License.
|
|
* You may obtain a copy of the License at
|
|
*
|
|
* http://www.apache.org/licenses/LICENSE-2.0
|
|
*
|
|
* Unless required by applicable law or agreed to in writing, software
|
|
* distributed under the License is distributed on an "AS IS" BASIS,
|
|
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
* See the License for the specific language governing permissions and
|
|
* limitations under the License.
|
|
*/
|
|
|
|
package loader
|
|
|
|
import (
|
|
`os`
|
|
`sort`
|
|
`unsafe`
|
|
|
|
`github.com/bytedance/sonic/internal/rt`
|
|
)
|
|
|
|
type funcTab struct {
|
|
entry uint32
|
|
funcoff uint32
|
|
}
|
|
|
|
type pcHeader struct {
|
|
magic uint32 // 0xFFFFFFF0
|
|
pad1, pad2 uint8 // 0,0
|
|
minLC uint8 // min instruction size
|
|
ptrSize uint8 // size of a ptr in bytes
|
|
nfunc int // number of functions in the module
|
|
nfiles uint // number of entries in the file tab
|
|
textStart uintptr // base for function entry PC offsets in this module, equal to moduledata.text
|
|
funcnameOffset uintptr // offset to the funcnametab variable from pcHeader
|
|
cuOffset uintptr // offset to the cutab variable from pcHeader
|
|
filetabOffset uintptr // offset to the filetab variable from pcHeader
|
|
pctabOffset uintptr // offset to the pctab variable from pcHeader
|
|
pclnOffset uintptr // offset to the pclntab variable from pcHeader
|
|
}
|
|
|
|
type bitVector struct {
|
|
n int32 // # of bits
|
|
bytedata *uint8
|
|
}
|
|
|
|
type ptabEntry struct {
|
|
name int32
|
|
typ int32
|
|
}
|
|
|
|
type textSection struct {
|
|
vaddr uintptr // prelinked section vaddr
|
|
end uintptr // vaddr + section length
|
|
baseaddr uintptr // relocated section address
|
|
}
|
|
|
|
type modulehash struct {
|
|
modulename string
|
|
linktimehash string
|
|
runtimehash *string
|
|
}
|
|
|
|
// findfuncbucket is an array of these structures.
|
|
// Each bucket represents 4096 bytes of the text segment.
|
|
// Each subbucket represents 256 bytes of the text segment.
|
|
// To find a function given a pc, locate the bucket and subbucket for
|
|
// that pc. Add together the idx and subbucket value to obtain a
|
|
// function index. Then scan the functab array starting at that
|
|
// index to find the target function.
|
|
// This table uses 20 bytes for every 4096 bytes of code, or ~0.5% overhead.
|
|
type findfuncbucket struct {
|
|
idx uint32
|
|
_SUBBUCKETS [16]byte
|
|
}
|
|
|
|
type compilationUnit struct {
|
|
fileNames []string
|
|
}
|
|
|
|
func makeFtab(funcs []_func, maxpc uint32) (ftab []funcTab, pclntabSize int64, startLocations []uint32) {
|
|
// Allocate space for the pc->func table. This structure consists of a pc offset
|
|
// and an offset to the func structure. After that, we have a single pc
|
|
// value that marks the end of the last function in the binary.
|
|
pclntabSize = int64(len(funcs)*2*int(_PtrSize) + int(_PtrSize))
|
|
startLocations = make([]uint32, len(funcs))
|
|
for i, f := range funcs {
|
|
pclntabSize = rnd(pclntabSize, int64(_PtrSize))
|
|
//writePCToFunc
|
|
startLocations[i] = uint32(pclntabSize)
|
|
pclntabSize += int64(uint8(_FUNC_SIZE)+f.nfuncdata*4+uint8(f.npcdata)*4)
|
|
}
|
|
|
|
ftab = make([]funcTab, 0, len(funcs)+1)
|
|
|
|
// write a map of pc->func info offsets
|
|
for i, f := range funcs {
|
|
ftab = append(ftab, funcTab{uint32(f.entryOff), uint32(startLocations[i])})
|
|
}
|
|
|
|
// Final entry of table is just end pc offset.
|
|
ftab = append(ftab, funcTab{maxpc, 0})
|
|
return
|
|
}
|
|
|
|
// Pcln table format: [...]funcTab + [...]_Func
|
|
func makePclntable(size int64, startLocations []uint32, funcs []_func, maxpc uint32, pcdataOffs [][]uint32, funcdataOffs [][]uint32) (pclntab []byte) {
|
|
// Allocate space for the pc->func table. This structure consists of a pc offset
|
|
// and an offset to the func structure. After that, we have a single pc
|
|
// value that marks the end of the last function in the binary.
|
|
pclntab = make([]byte, size, size)
|
|
|
|
// write a map of pc->func info offsets
|
|
offs := 0
|
|
for i, f := range funcs {
|
|
byteOrder.PutUint32(pclntab[offs:offs+4], uint32(f.entryOff))
|
|
byteOrder.PutUint32(pclntab[offs+4:offs+8], uint32(startLocations[i]))
|
|
offs += 8
|
|
}
|
|
// Final entry of table is just end pc offset.
|
|
byteOrder.PutUint32(pclntab[offs:offs+4], maxpc)
|
|
|
|
// write func info table
|
|
for i := range funcs {
|
|
off := startLocations[i]
|
|
|
|
// write _func structure to pclntab
|
|
fb := rt.BytesFrom(unsafe.Pointer(&funcs[i]), int(_FUNC_SIZE), int(_FUNC_SIZE))
|
|
copy(pclntab[off:off+uint32(_FUNC_SIZE)], fb)
|
|
off += uint32(_FUNC_SIZE)
|
|
|
|
// NOTICE: _func.pcdata always starts from PcUnsafePoint, which is index 3
|
|
for j := 3; j < len(pcdataOffs[i]); j++ {
|
|
byteOrder.PutUint32(pclntab[off:off+4], uint32(pcdataOffs[i][j]))
|
|
off += 4
|
|
}
|
|
|
|
// funcdata refs as offsets from gofunc
|
|
for _, funcdata := range funcdataOffs[i] {
|
|
byteOrder.PutUint32(pclntab[off:off+4], uint32(funcdata))
|
|
off += 4
|
|
}
|
|
|
|
}
|
|
|
|
return
|
|
}
|
|
|
|
// findfunc table used to map pc to belonging func,
|
|
// returns the index in the func table.
|
|
//
|
|
// All text section are divided into buckets sized _BUCKETSIZE(4K):
|
|
// every bucket is divided into _SUBBUCKETS sized _SUB_BUCKETSIZE(64),
|
|
// and it has a base idx to plus the offset stored in jth subbucket.
|
|
// see findfunc() in runtime/symtab.go
|
|
func writeFindfunctab(out *[]byte, ftab []funcTab) (start int) {
|
|
start = len(*out)
|
|
|
|
max := ftab[len(ftab)-1].entry
|
|
min := ftab[0].entry
|
|
nbuckets := (max - min + _BUCKETSIZE - 1) / _BUCKETSIZE
|
|
n := (max - min + _SUB_BUCKETSIZE - 1) / _SUB_BUCKETSIZE
|
|
|
|
tab := make([]findfuncbucket, 0, nbuckets)
|
|
var s, e = 0, 0
|
|
for i := 0; i<int(nbuckets); i++ {
|
|
// store the start s-th func of the bucket
|
|
var fb = findfuncbucket{idx: uint32(s)}
|
|
|
|
// find the last e-th func of the bucket
|
|
var pc = min + uint32((i+1)*_BUCKETSIZE)
|
|
for ; e < len(ftab)-1 && ftab[e+1].entry <= pc; e++ {}
|
|
|
|
for j := 0; j<_SUBBUCKETS && (i*_SUBBUCKETS+j)<int(n); j++ {
|
|
// store the start func of the subbucket
|
|
fb._SUBBUCKETS[j] = byte(uint32(s) - fb.idx)
|
|
|
|
// find the s-th end func of the subbucket
|
|
pc = min + uint32(i*_BUCKETSIZE) + uint32((j+1)*_SUB_BUCKETSIZE)
|
|
for ; s < len(ftab)-1 && ftab[s+1].entry <= pc; s++ {}
|
|
}
|
|
|
|
s = e
|
|
tab = append(tab, fb)
|
|
}
|
|
|
|
// write findfuncbucket
|
|
if len(tab) > 0 {
|
|
size := int(unsafe.Sizeof(findfuncbucket{}))*len(tab)
|
|
*out = append(*out, rt.BytesFrom(unsafe.Pointer(&tab[0]), size, size)...)
|
|
}
|
|
return
|
|
}
|
|
|
|
func makeModuledata(name string, filenames []string, funcsp *[]Func, text []byte) (mod *moduledata) {
|
|
mod = new(moduledata)
|
|
mod.modulename = name
|
|
|
|
// sort funcs by entry
|
|
funcs := *funcsp
|
|
sort.Slice(funcs, func(i, j int) bool {
|
|
return funcs[i].EntryOff < funcs[j].EntryOff
|
|
})
|
|
*funcsp = funcs
|
|
|
|
// make filename table
|
|
cu := make([]string, 0, len(filenames))
|
|
cu = append(cu, filenames...)
|
|
cutab, filetab, cuOffs := makeFilenametab([]compilationUnit{{cu}})
|
|
mod.cutab = cutab
|
|
mod.filetab = filetab
|
|
|
|
// make funcname table
|
|
funcnametab, nameOffs := makeFuncnameTab(funcs)
|
|
mod.funcnametab = funcnametab
|
|
|
|
// mmap() text and funcdata segements
|
|
p := os.Getpagesize()
|
|
size := int(rnd(int64(len(text)), int64(p)))
|
|
addr := mmap(size)
|
|
// copy the machine code
|
|
s := rt.BytesFrom(unsafe.Pointer(addr), len(text), size)
|
|
copy(s, text)
|
|
// make it executable
|
|
mprotect(addr, size)
|
|
|
|
// assign addresses
|
|
mod.text = addr
|
|
mod.etext = addr + uintptr(size)
|
|
mod.minpc = addr
|
|
mod.maxpc = addr + uintptr(len(text))
|
|
|
|
// make pcdata table
|
|
// NOTICE: _func only use offset to index pcdata, thus no need mmap() pcdata
|
|
cuOff := cuOffs[0]
|
|
pctab, pcdataOffs, _funcs := makePctab(funcs, cuOff, nameOffs)
|
|
mod.pctab = pctab
|
|
|
|
// write func data
|
|
// NOTICE: _func use mod.gofunc+offset to directly point funcdata, thus need cache funcdata
|
|
// TODO: estimate accurate capacity
|
|
cache := make([]byte, 0, len(funcs)*int(_PtrSize))
|
|
fstart, funcdataOffs := writeFuncdata(&cache, funcs)
|
|
|
|
// make pc->func (binary search) func table
|
|
ftab, pclntSize, startLocations := makeFtab(_funcs, uint32(len(text)))
|
|
mod.ftab = ftab
|
|
|
|
// write pc->func (modmap) findfunc table
|
|
ffstart := writeFindfunctab(&cache, ftab)
|
|
|
|
// cache funcdata and findfuncbucket
|
|
moduleCache.Lock()
|
|
moduleCache.m[mod] = cache
|
|
moduleCache.Unlock()
|
|
mod.gofunc = uintptr(unsafe.Pointer(&cache[fstart]))
|
|
mod.findfunctab = uintptr(unsafe.Pointer(&cache[ffstart]))
|
|
|
|
// make pclnt table
|
|
pclntab := makePclntable(pclntSize, startLocations, _funcs, uint32(len(text)), pcdataOffs, funcdataOffs)
|
|
mod.pclntable = pclntab
|
|
|
|
// make pc header
|
|
mod.pcHeader = &pcHeader {
|
|
magic : _Magic,
|
|
minLC : _MinLC,
|
|
ptrSize : _PtrSize,
|
|
nfunc : len(funcs),
|
|
nfiles: uint(len(cu)),
|
|
textStart: mod.text,
|
|
funcnameOffset: getOffsetOf(moduledata{}, "funcnametab"),
|
|
cuOffset: getOffsetOf(moduledata{}, "cutab"),
|
|
filetabOffset: getOffsetOf(moduledata{}, "filetab"),
|
|
pctabOffset: getOffsetOf(moduledata{}, "pctab"),
|
|
pclnOffset: getOffsetOf(moduledata{}, "pclntable"),
|
|
}
|
|
|
|
// sepecial case: gcdata and gcbss must by non-empty
|
|
mod.gcdata = uintptr(unsafe.Pointer(&emptyByte))
|
|
mod.gcbss = uintptr(unsafe.Pointer(&emptyByte))
|
|
|
|
return
|
|
}
|
|
|
|
// makePctab generates pcdelta->valuedelta tables for functions,
|
|
// and returns the table and the entry offset of every kind pcdata in the table.
|
|
func makePctab(funcs []Func, cuOffset uint32, nameOffset []int32) (pctab []byte, pcdataOffs [][]uint32, _funcs []_func) {
|
|
_funcs = make([]_func, len(funcs))
|
|
|
|
// Pctab offsets of 0 are considered invalid in the runtime. We respect
|
|
// that by just padding a single byte at the beginning of runtime.pctab,
|
|
// that way no real offsets can be zero.
|
|
pctab = make([]byte, 1, 12*len(funcs)+1)
|
|
pcdataOffs = make([][]uint32, len(funcs))
|
|
|
|
for i, f := range funcs {
|
|
_f := &_funcs[i]
|
|
|
|
var writer = func(pc *Pcdata) {
|
|
var ab []byte
|
|
var err error
|
|
if pc != nil {
|
|
ab, err = pc.MarshalBinary()
|
|
if err != nil {
|
|
panic(err)
|
|
}
|
|
pcdataOffs[i] = append(pcdataOffs[i], uint32(len(pctab)))
|
|
} else {
|
|
ab = []byte{0}
|
|
pcdataOffs[i] = append(pcdataOffs[i], _PCDATA_INVALID_OFFSET)
|
|
}
|
|
pctab = append(pctab, ab...)
|
|
}
|
|
|
|
if f.Pcsp != nil {
|
|
_f.pcsp = uint32(len(pctab))
|
|
}
|
|
writer(f.Pcsp)
|
|
if f.Pcfile != nil {
|
|
_f.pcfile = uint32(len(pctab))
|
|
}
|
|
writer(f.Pcfile)
|
|
if f.Pcline != nil {
|
|
_f.pcln = uint32(len(pctab))
|
|
}
|
|
writer(f.Pcline)
|
|
writer(f.PcUnsafePoint)
|
|
writer(f.PcStackMapIndex)
|
|
writer(f.PcInlTreeIndex)
|
|
writer(f.PcArgLiveIndex)
|
|
|
|
_f.entryOff = f.EntryOff
|
|
_f.nameOff = nameOffset[i]
|
|
_f.args = f.ArgsSize
|
|
_f.deferreturn = f.DeferReturn
|
|
// NOTICE: _func.pcdata is always as [PCDATA_UnsafePoint(0) : PCDATA_ArgLiveIndex(3)]
|
|
_f.npcdata = uint32(_N_PCDATA)
|
|
_f.cuOffset = cuOffset
|
|
_f.funcID = f.ID
|
|
_f.flag = f.Flag
|
|
_f.nfuncdata = uint8(_N_FUNCDATA)
|
|
}
|
|
|
|
return
|
|
}
|
|
|
|
func registerFunction(name string, pc uintptr, textSize uintptr, fp int, args int, size uintptr, argptrs uintptr, localptrs uintptr) {}
|