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// 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.
#include "runtime.h"
// Atomic add and return new value.
#pragma textflag 7
uint32
runtime·xadd(uint32 volatile *val, int32 delta)
{
uint32 oval, nval;
for(;;){
oval = *val;
nval = oval + delta;
if(runtime·cas(val, oval, nval))
return nval;
}
}
#pragma textflag 7
uint32
runtime·xchg(uint32 volatile* addr, uint32 v)
{
uint32 old;
for(;;) {
old = *addr;
if(runtime·cas(addr, old, v))
return old;
}
}
#pragma textflag 7
void
runtime·procyield(uint32 cnt)
{
uint32 volatile i;
for(i = 0; i < cnt; i++) {
}
}
#pragma textflag 7
uint32
runtime·atomicload(uint32 volatile* addr)
{
return runtime·xadd(addr, 0);
}
#pragma textflag 7
void*
runtime·atomicloadp(void* volatile* addr)
{
return (void*)runtime·xadd((uint32 volatile*)addr, 0);
}
#pragma textflag 7
void
runtime·atomicstorep(void* volatile* addr, void* v)
{
void *old;
for(;;) {
old = *addr;
if(runtime·casp(addr, old, v))
return;
}
}
#pragma textflag 7
void
runtime·atomicstore(uint32 volatile* addr, uint32 v)
{
uint32 old;
for(;;) {
old = *addr;
if(runtime·cas(addr, old, v))
return;
}
}
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