实现基础web服务器

vendor/github.com/bytedance/sonic/internal/loader/funcdata_go120.go

@@ -0,0 +1,201 @@
+// +build go1.20
+
+/*
+ * 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 (
+    `unsafe`
+
+    `github.com/bytedance/sonic/internal/rt`
+)
+
+// A FuncFlag holds bits about a function.
+// This list must match the list in cmd/internal/objabi/funcid.go.
+type funcFlag uint8
+
+type _Func struct {
+    entryOff    uint32 // start pc
+    nameoff     int32   // function name
+    args        int32   // in/out args size
+    deferreturn uint32  // offset of start of a deferreturn call instruction from entry, if any.
+    pcsp        uint32
+    pcfile      uint32
+    pcln        uint32
+    npcdata     uint32
+    cuOffset    uint32  // runtime.cutab offset of this function's CU
+    funcID      uint8   // set for certain special runtime functions
+    flag        funcFlag
+    _           [1]byte // pad
+    nfuncdata   uint8   // must be last
+    argptrs     uint32
+    localptrs   uint32
+}
+
+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
+    length   uintptr // section length
+    baseaddr uintptr // relocated section address
+}
+
+type _ModuleData struct {
+    pcHeader              *_PCHeader
+    funcnametab           []byte
+    cutab                 []uint32
+    filetab               []byte
+    pctab                 []byte
+    pclntable             []byte
+    ftab                  []_FuncTab
+    findfunctab           *_FindFuncBucket
+    minpc, maxpc          uintptr
+    text, etext           uintptr
+    noptrdata, enoptrdata uintptr
+    data, edata           uintptr
+    bss, ebss             uintptr
+    noptrbss, enoptrbss   uintptr
+    end, gcdata, gcbss    uintptr
+    types, etypes         uintptr
+    rodata                uintptr
+    gofunc                uintptr 
+    textsectmap           []_TextSection
+    typelinks             []int32
+    itablinks             []unsafe.Pointer
+    ptab                  []_PtabEntry
+    pluginpath            string
+    pkghashes             []struct{}
+    modulename            string
+    modulehashes          []struct{}
+    hasmain               uint8
+    gcdatamask, gcbssmask _BitVector
+    typemap               map[int32]unsafe.Pointer
+    bad                   bool
+    next                  *_ModuleData
+}
+
+
+type _FindFuncBucket struct {
+    idx        uint32
+    subbuckets [16]byte
+}
+
+
+
+func makePCtab(fp int) []byte {
+    return append([]byte{0}, encodeVariant((fp + 1) << 1)...)
+}
+
+func registerFunction(name string, pc uintptr, textSize uintptr, fp int, args int, size uintptr, argPtrs []bool, localPtrs []bool) {
+    mod := new(_ModuleData)
+
+    minpc := pc
+    maxpc := pc + size
+
+    findFuncTab := make([]_FindFuncBucket, textSize/4096 + 1)
+
+    modHeader := &_PCHeader {
+        magic   : 0xfffffff0,
+        minLC   : 1,
+        nfunc   : 1,
+        ptrSize : 4 << (^uintptr(0) >> 63),
+        textStart: minpc,
+    }
+
+    // cache arg and local stackmap
+    argptrs, localptrs := cacheStackmap(argPtrs, localPtrs, mod)
+
+    base := argptrs
+    if argptrs > localptrs {
+        base = localptrs
+    }
+
+    /* function entry */
+    lnt := []_Func {{
+        entryOff  : 0,
+        nameoff   : 1,
+        args      : int32(args),
+        pcsp      : 1,
+        nfuncdata : 2,
+        argptrs: uint32(argptrs - base),
+        localptrs: uint32(localptrs - base),
+    }}
+    nlnt := len(lnt)*int(unsafe.Sizeof(_Func{}))
+    plnt := unsafe.Pointer(&lnt[0])
+
+    /* function table */
+    ftab := []_FuncTab {
+        {entry   : 0, funcoff : 16},    
+        {entry   : uint32(size)},
+    }
+    nftab := len(ftab)*int(unsafe.Sizeof(_FuncTab{}))
+    pftab := unsafe.Pointer(&ftab[0])
+
+    pclntab := make([]byte, 0, nftab + nlnt)
+    pclntab = append(pclntab, rt.BytesFrom(pftab, nftab, nftab)...)
+    pclntab = append(pclntab, rt.BytesFrom(plnt, nlnt, nlnt)...)
+
+    /* module data */
+    *mod = _ModuleData {
+        pcHeader    : modHeader,
+        funcnametab : append(append([]byte{0}, name...), 0),
+        pctab       : append(makePCtab(fp), encodeVariant(int(size))...),
+        pclntable   : pclntab,
+        ftab        : ftab,
+        text        : minpc,
+        etext       : pc + textSize,
+        findfunctab : &findFuncTab[0],
+        minpc       : minpc,
+        maxpc       : maxpc,
+        modulename  : name,
+        gcdata: uintptr(unsafe.Pointer(&emptyByte)),
+        gcbss: uintptr(unsafe.Pointer(&emptyByte)),
+        gofunc: base,
+    }
+
+    /* verify and register the new module */
+    moduledataverify1(mod)
+    registerModule(mod)
+}