1 // Copyright 2015 The Go Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style 3 // license that can be found in the LICENSE file. 4 5 package runtime 6 7 import "unsafe" 8 9 //go:noescape 10 func xadd(ptr *uint32, delta int32) uint32 11 12 //go:noescape 13 func xadd64(ptr *uint64, delta int64) uint64 14 15 //go:noescape 16 //go:linkname xadduintptr runtime.xadd64 17 func xadduintptr(ptr *uintptr, delta uintptr) uintptr 18 19 //go:noescape 20 func xchg(ptr *uint32, new uint32) uint32 21 22 //go:noescape 23 func xchg64(ptr *uint64, new uint64) uint64 24 25 // NO go:noescape annotation; see atomic_pointer.go. 26 func xchgp1(ptr unsafe.Pointer, new unsafe.Pointer) unsafe.Pointer 27 28 //go:noescape 29 func xchguintptr(ptr *uintptr, new uintptr) uintptr 30 31 //go:noescape 32 func atomicload(ptr *uint32) uint32 33 34 //go:noescape 35 func atomicload64(ptr *uint64) uint64 36 37 //go:noescape 38 func atomicloadp(ptr unsafe.Pointer) unsafe.Pointer 39 40 //go:nosplit 41 func atomicor8(addr *uint8, v uint8) { 42 // TODO(dfc) implement this in asm. 43 // Align down to 4 bytes and use 32-bit CAS. 44 uaddr := uintptr(unsafe.Pointer(addr)) 45 addr32 := (*uint32)(unsafe.Pointer(uaddr &^ 3)) 46 word := uint32(v) << ((uaddr & 3) * 8) // little endian 47 for { 48 old := *addr32 49 if cas(addr32, old, old|word) { 50 return 51 } 52 } 53 } 54 55 //go:nosplit 56 func atomicand8(addr *uint8, v uint8) { 57 // TODO(dfc) implement this in asm. 58 // Align down to 4 bytes and use 32-bit CAS. 59 uaddr := uintptr(unsafe.Pointer(addr)) 60 addr32 := (*uint32)(unsafe.Pointer(uaddr &^ 3)) 61 word := uint32(v) << ((uaddr & 3) * 8) // little endian 62 mask := uint32(0xFF) << ((uaddr & 3) * 8) // little endian 63 word |= ^mask 64 for { 65 old := *addr32 66 if cas(addr32, old, old&word) { 67 return 68 } 69 } 70 } 71 72 //go:noescape 73 func cas64(ptr *uint64, old, new uint64) bool 74 75 //go:noescape 76 func atomicstore(ptr *uint32, val uint32) 77 78 //go:noescape 79 func atomicstore64(ptr *uint64, val uint64) 80 81 // NO go:noescape annotation; see atomic_pointer.go. 82 func atomicstorep1(ptr unsafe.Pointer, val unsafe.Pointer) 83
