blob: 0e2d77ade176bc908374721804a9c54e0d9c68bf [file] [log] [blame]
// Copyright 2016 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// +build mips mipsle
// Export some functions via linkname to assembly in sync/atomic.
//go:linkname Xadd64
//go:linkname Xchg64
//go:linkname Cas64
//go:linkname Load64
//go:linkname Store64
package atomic
import (
"internal/cpu"
"unsafe"
)
// TODO implement lock striping
var lock struct {
state uint32
pad [cpu.CacheLinePadSize - 4]byte
}
//go:noescape
func spinLock(state *uint32)
//go:noescape
func spinUnlock(state *uint32)
//go:nosplit
func lockAndCheck(addr *uint64) {
// ensure 8-byte alignment
if uintptr(unsafe.Pointer(addr))&7 != 0 {
addr = nil
}
// force dereference before taking lock
_ = *addr
spinLock(&lock.state)
}
//go:nosplit
func unlock() {
spinUnlock(&lock.state)
}
//go:nosplit
func unlockNoFence() {
lock.state = 0
}
//go:nosplit
func Xadd64(addr *uint64, delta int64) (new uint64) {
lockAndCheck(addr)
new = *addr + uint64(delta)
*addr = new
unlock()
return
}
//go:nosplit
func Xchg64(addr *uint64, new uint64) (old uint64) {
lockAndCheck(addr)
old = *addr
*addr = new
unlock()
return
}
//go:nosplit
func Cas64(addr *uint64, old, new uint64) (swapped bool) {
lockAndCheck(addr)
if (*addr) == old {
*addr = new
unlock()
return true
}
unlockNoFence()
return false
}
//go:nosplit
func Load64(addr *uint64) (val uint64) {
lockAndCheck(addr)
val = *addr
unlock()
return
}
//go:nosplit
func Store64(addr *uint64, val uint64) {
lockAndCheck(addr)
*addr = val
unlock()
return
}
//go:noescape
func Xadd(ptr *uint32, delta int32) uint32
//go:noescape
func Xadduintptr(ptr *uintptr, delta uintptr) uintptr
//go:noescape
func Xchg(ptr *uint32, new uint32) uint32
//go:noescape
func Xchguintptr(ptr *uintptr, new uintptr) uintptr
//go:noescape
func Load(ptr *uint32) uint32
//go:noescape
func Load8(ptr *uint8) uint8
// NO go:noescape annotation; *ptr escapes if result escapes (#31525)
func Loadp(ptr unsafe.Pointer) unsafe.Pointer
//go:noescape
func LoadAcq(ptr *uint32) uint32
//go:noescape
func And8(ptr *uint8, val uint8)
//go:noescape
func Or8(ptr *uint8, val uint8)
//go:noescape
func Store(ptr *uint32, val uint32)
//go:noescape
func Store8(ptr *uint8, val uint8)
// NO go:noescape annotation; see atomic_pointer.go.
func StorepNoWB(ptr unsafe.Pointer, val unsafe.Pointer)
//go:noescape
func StoreRel(ptr *uint32, val uint32)
//go:noescape
func CasRel(addr *uint32, old, new uint32) bool