75 lines
1.8 KiB
Go
75 lines
1.8 KiB
Go
//go:build llgo && !baremetal && !nogc
|
|
|
|
/*
|
|
* Copyright (c) 2025 The GoPlus Authors (goplus.org). All rights reserved.
|
|
*
|
|
* 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 tls
|
|
|
|
import (
|
|
"unsafe"
|
|
|
|
c "github.com/goplus/llgo/runtime/internal/clite"
|
|
"github.com/goplus/llgo/runtime/internal/clite/bdwgc"
|
|
)
|
|
|
|
const slotRegistered = 1 << iota
|
|
|
|
const maxSlotSize = 1 << 20 // 1 MiB sanity cap
|
|
|
|
type slot[T any] struct {
|
|
value T
|
|
state uintptr
|
|
destructor func(*T)
|
|
}
|
|
|
|
func registerSlot[T any](s *slot[T]) {
|
|
if s.state&slotRegistered != 0 {
|
|
return
|
|
}
|
|
start, end := s.rootRange()
|
|
size := uintptr(end) - uintptr(start)
|
|
if size == 0 {
|
|
return
|
|
}
|
|
if size > maxSlotSize {
|
|
panic("tls: slot size exceeds maximum")
|
|
}
|
|
bdwgc.AddRoots(start, end)
|
|
s.state |= slotRegistered
|
|
}
|
|
|
|
func deregisterSlot[T any](s *slot[T]) {
|
|
if s == nil || s.state&slotRegistered == 0 {
|
|
return
|
|
}
|
|
s.state &^= slotRegistered
|
|
start, end := s.rootRange()
|
|
if uintptr(end) > uintptr(start) {
|
|
bdwgc.RemoveRoots(start, end)
|
|
}
|
|
}
|
|
|
|
func (s *slot[T]) rootRange() (start, end c.Pointer) {
|
|
begin := unsafe.Pointer(s)
|
|
size := unsafe.Sizeof(*s)
|
|
beginAddr := uintptr(begin)
|
|
if beginAddr > ^uintptr(0)-size {
|
|
panic("tls: pointer arithmetic overflow in rootRange")
|
|
}
|
|
endPtr := unsafe.Pointer(beginAddr + size)
|
|
return c.Pointer(begin), c.Pointer(endPtr)
|
|
}
|