// Copyright 2009 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. package runtime import (	"runtime/internal/atomic"	"unsafe") // These functions cannot have go:noescape annotations,// because while ptr does not escape, new does.// If new is marked as not escaping, the compiler will make incorrect// escape analysis decisions about the pointer value being stored.// Instead, these are wrappers around the actual atomics (casp1 and so on)// that use noescape to convey which arguments do not escape.//// Additionally, these functions must update the shadow heap for// write barrier checking. //go:nosplitfunc atomicstorep(ptr unsafe.Pointer, new unsafe.Pointer) {	atomic.Storep1(noescape(ptr), new)	writebarrierptr_nostore((*uintptr)(ptr), uintptr(new))} //go:nosplitfunc casp(ptr *unsafe.Pointer, old, new unsafe.Pointer) bool {	if !atomic.Casp1((*unsafe.Pointer)(noescape(unsafe.Pointer(ptr))), noescape(old), new) {		return false	}	writebarrierptr_nostore((*uintptr)(unsafe.Pointer(ptr)), uintptr(new))	return true} // Like above, but implement in terms of sync/atomic's uintptr operations.// We cannot just call the runtime routines, because the race detector expects// to be able to intercept the sync/atomic forms but not the runtime forms. //go:linkname sync_atomic_StoreUintptr sync/atomic.StoreUintptrfunc sync_atomic_StoreUintptr(ptr *uintptr, new uintptr) //go:linkname sync_atomic_StorePointer sync/atomic.StorePointer//go:nosplitfunc sync_atomic_StorePointer(ptr *unsafe.Pointer, new unsafe.Pointer) {	sync_atomic_StoreUintptr((*uintptr)(unsafe.Pointer(ptr)), uintptr(new))	atomic.Storep1(noescape(unsafe.Pointer(ptr)), new)	writebarrierptr_nostore((*uintptr)(unsafe.Pointer(ptr)), uintptr(new))} //go:linkname sync_atomic_SwapUintptr sync/atomic.SwapUintptrfunc sync_atomic_SwapUintptr(ptr *uintptr, new uintptr) uintptr //go:linkname sync_atomic_SwapPointer sync/atomic.SwapPointer//go:nosplitfunc sync_atomic_SwapPointer(ptr unsafe.Pointer, new unsafe.Pointer) unsafe.Pointer {	old := unsafe.Pointer(sync_atomic_SwapUintptr((*uintptr)(noescape(ptr)), uintptr(new)))	writebarrierptr_nostore((*uintptr)(ptr), uintptr(new))	return old} //go:linkname sync_atomic_CompareAndSwapUintptr sync/atomic.CompareAndSwapUintptrfunc sync_atomic_CompareAndSwapUintptr(ptr *uintptr, old, new uintptr) bool //go:linkname sync_atomic_CompareAndSwapPointer sync/atomic.CompareAndSwapPointer//go:nosplitfunc sync_atomic_CompareAndSwapPointer(ptr *unsafe.Pointer, old, new unsafe.Pointer) bool {	if !sync_atomic_CompareAndSwapUintptr((*uintptr)(noescape(unsafe.Pointer(ptr))), uintptr(old), uintptr(new)) {		return false	}	writebarrierptr_nostore((*uintptr)(unsafe.Pointer(ptr)), uintptr(new))	return true}