podman

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//go:build go1.16 && !go1.22
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// +build go1.16,!go1.22
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/*
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 * Copyright 2021 ByteDance Inc.
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 *
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 * Licensed under the Apache License, Version 2.0 (the "License");
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 * you may not use this file except in compliance with the License.
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 * You may obtain a copy of the License at
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 *
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 *     http://www.apache.org/licenses/LICENSE-2.0
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 *
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 * Unless required by applicable law or agreed to in writing, software
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 * distributed under the License is distributed on an "AS IS" BASIS,
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 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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 * See the License for the specific language governing permissions and
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 * limitations under the License.
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 */
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package loader
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import (
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    `github.com/bytedance/sonic/internal/rt`
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)
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// LoadFuncs loads only one function as module, and returns the function pointer
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//   - text: machine code
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//   - funcName: function name
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//   - frameSize: stack frame size. 
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//   - argSize: argument total size (in bytes)
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//   - argPtrs: indicates if a slot (8 Bytes) of arguments memory stores pointer, from low to high
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//   - localPtrs: indicates if a slot (8 Bytes) of local variants memory stores pointer, from low to high
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// 
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// WARN: 
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//   - the function MUST has fixed SP offset equaling to this, otherwise it go.gentraceback will fail
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//   - the function MUST has only one stack map for all arguments and local variants
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func (self Loader) LoadOne(text []byte, funcName string, frameSize int, argSize int, argPtrs []bool, localPtrs []bool) Function {
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    size := uint32(len(text))
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    fn := Func{
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        Name: funcName,
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        TextSize: size,
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        ArgsSize: int32(argSize),
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    }
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    // NOTICE: suppose the function has fixed SP offset equaling to frameSize, thus make only one pcsp pair
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    fn.Pcsp = &Pcdata{
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        {PC: size, Val: int32(frameSize)},
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    }
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    if self.NoPreempt {
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        fn.PcUnsafePoint = &Pcdata{
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            {PC: size, Val: PCDATA_UnsafePointUnsafe},
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        }
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    } else {
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        fn.PcUnsafePoint = &Pcdata{
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            {PC: size, Val: PCDATA_UnsafePointSafe},
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        }
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    }
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    // NOTICE: suppose the function has only one stack map at index 0
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    fn.PcStackMapIndex = &Pcdata{
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        {PC: size, Val: 0},
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    }
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    if argPtrs != nil {
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        args := rt.StackMapBuilder{}
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        for _, b := range argPtrs {
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            args.AddField(b)
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        }
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        fn.ArgsPointerMaps = args.Build()
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    }
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    if localPtrs != nil {
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        locals := rt .StackMapBuilder{}
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        for _, b := range localPtrs {
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            locals.AddField(b)
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        }
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        fn.LocalsPointerMaps = locals.Build()
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    }
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    out := Load(text, []Func{fn}, self.Name + funcName, []string{self.File})
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    return out[0]
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}
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// Load loads given machine codes and corresponding function information into go moduledata
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// and returns runnable function pointer
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// WARN: this API is experimental, use it carefully
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func Load(text []byte, funcs []Func, modulename string, filenames []string) (out []Function) {
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    ids := make([]string, len(funcs))
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    for i, f := range funcs {
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        ids[i] = f.Name
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    }
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    // generate module data and allocate memory address
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    mod := makeModuledata(modulename, filenames, &funcs, text)
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    // verify and register the new module
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    moduledataverify1(mod)
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    registerModule(mod)
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    // 
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    // encapsulate function address
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    out = make([]Function, len(funcs))
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    for i, s := range ids {
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        for _, f := range funcs {
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            if f.Name == s {
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                m := uintptr(mod.text + uintptr(f.EntryOff))
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                out[i] = Function(&m)
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            }
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        }
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    }
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    return 
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}
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