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// Copyright 2010 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"
#include "defs_GOOS_GOARCH.h"
#include "arch_GOARCH.h"
#include "malloc.h"
#include "os_GOOS.h"
extern byte end[];
static byte *bloc = { end };
static Lock memlock;
enum
{
Round = PAGESIZE-1
};
void*
runtime·SysAlloc(uintptr nbytes, uint64 *stat)
{
uintptr bl;
runtime·lock(&memlock);
// Plan 9 sbrk from /sys/src/libc/9sys/sbrk.c
bl = ((uintptr)bloc + Round) & ~Round;
if(runtime·brk_((void*)(bl + nbytes)) < 0) {
runtime·unlock(&memlock);
return nil;
}
bloc = (byte*)bl + nbytes;
runtime·unlock(&memlock);
runtime·xadd64(stat, nbytes);
return (void*)bl;
}
void
runtime·SysFree(void *v, uintptr nbytes, uint64 *stat)
{
runtime·xadd64(stat, -(uint64)nbytes);
runtime·lock(&memlock);
// from tiny/mem.c
// Push pointer back if this is a free
// of the most recent SysAlloc.
nbytes += (nbytes + Round) & ~Round;
if(bloc == (byte*)v+nbytes)
bloc -= nbytes;
runtime·unlock(&memlock);
}
void
runtime·SysUnused(void *v, uintptr nbytes)
{
USED(v, nbytes);
}
void
runtime·SysUsed(void *v, uintptr nbytes)
{
USED(v, nbytes);
}
void
runtime·SysMap(void *v, uintptr nbytes, bool reserved, uint64 *stat)
{
USED(v, nbytes, reserved, stat);
}
void
runtime·SysFault(void *v, uintptr nbytes)
{
USED(v, nbytes);
}
void*
runtime·SysReserve(void *v, uintptr nbytes, bool *reserved)
{
USED(v);
*reserved = true;
return runtime·SysAlloc(nbytes, &mstats.heap_sys);
}
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