mirror of
https://github.com/golang/go
synced 2024-10-04 20:21:22 -06:00
e838334beb
R=golang-dev, bradfitz CC=golang-dev https://golang.org/cl/12798043
157 lines
2.5 KiB
C
157 lines
2.5 KiB
C
// Copyright 2009 The Go Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style
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// license that can be found in the LICENSE file.
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#include "runtime.h"
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#include "arch_GOARCH.h"
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#include "../../cmd/ld/textflag.h"
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static struct {
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Lock l;
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byte pad[CacheLineSize-sizeof(Lock)];
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} locktab[57];
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#define LOCK(addr) (&locktab[((uintptr)(addr)>>3)%nelem(locktab)].l)
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// Atomic add and return new value.
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#pragma textflag NOSPLIT
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uint32
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runtime·xadd(uint32 volatile *val, int32 delta)
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{
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uint32 oval, nval;
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for(;;){
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oval = *val;
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nval = oval + delta;
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if(runtime·cas(val, oval, nval))
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return nval;
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}
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}
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#pragma textflag NOSPLIT
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uint32
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runtime·xchg(uint32 volatile* addr, uint32 v)
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{
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uint32 old;
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for(;;) {
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old = *addr;
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if(runtime·cas(addr, old, v))
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return old;
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}
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}
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#pragma textflag NOSPLIT
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void
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runtime·procyield(uint32 cnt)
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{
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uint32 volatile i;
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for(i = 0; i < cnt; i++) {
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}
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}
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#pragma textflag NOSPLIT
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uint32
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runtime·atomicload(uint32 volatile* addr)
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{
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return runtime·xadd(addr, 0);
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}
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#pragma textflag NOSPLIT
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void*
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runtime·atomicloadp(void* volatile* addr)
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{
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return (void*)runtime·xadd((uint32 volatile*)addr, 0);
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}
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#pragma textflag NOSPLIT
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void
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runtime·atomicstorep(void* volatile* addr, void* v)
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{
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void *old;
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for(;;) {
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old = *addr;
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if(runtime·casp(addr, old, v))
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return;
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}
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}
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#pragma textflag NOSPLIT
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void
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runtime·atomicstore(uint32 volatile* addr, uint32 v)
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{
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uint32 old;
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for(;;) {
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old = *addr;
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if(runtime·cas(addr, old, v))
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return;
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}
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}
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#pragma textflag NOSPLIT
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bool
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runtime·cas64(uint64 volatile *addr, uint64 old, uint64 new)
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{
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bool res;
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runtime·lock(LOCK(addr));
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if(*addr == old) {
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*addr = new;
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res = true;
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} else {
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res = false;
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}
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runtime·unlock(LOCK(addr));
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return res;
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}
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#pragma textflag NOSPLIT
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uint64
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runtime·xadd64(uint64 volatile *addr, int64 delta)
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{
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uint64 res;
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runtime·lock(LOCK(addr));
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res = *addr + delta;
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*addr = res;
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runtime·unlock(LOCK(addr));
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return res;
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}
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#pragma textflag NOSPLIT
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uint64
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runtime·xchg64(uint64 volatile *addr, uint64 v)
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{
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uint64 res;
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runtime·lock(LOCK(addr));
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res = *addr;
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*addr = v;
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runtime·unlock(LOCK(addr));
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return res;
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}
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#pragma textflag NOSPLIT
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uint64
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runtime·atomicload64(uint64 volatile *addr)
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{
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uint64 res;
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runtime·lock(LOCK(addr));
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res = *addr;
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runtime·unlock(LOCK(addr));
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return res;
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}
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#pragma textflag NOSPLIT
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void
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runtime·atomicstore64(uint64 volatile *addr, uint64 v)
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{
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runtime·lock(LOCK(addr));
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*addr = v;
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runtime·unlock(LOCK(addr));
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}
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