| // 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 "malloc.h" |
| |
| // Assume there's an arbitrary amount of memory starting at "end". |
| // Sizing PC memory is beyond the scope of this demo. |
| |
| static byte *allocp; |
| |
| void* |
| runtime·SysAlloc(uintptr ask) |
| { |
| extern byte end[]; |
| byte *q; |
| |
| if(allocp == nil) { |
| allocp = end; |
| allocp += 7 & -(uintptr)allocp; |
| } |
| ask += 7 & -ask; |
| |
| q = allocp; |
| allocp += ask; |
| runtime·memclr(q, ask); |
| return q; |
| } |
| |
| void |
| runtime·SysFree(void *v, uintptr n) |
| { |
| // Push pointer back if this is a free |
| // of the most recent SysAlloc. |
| n += 7 & -n; |
| if(allocp == (byte*)v+n) |
| allocp -= n; |
| } |
| |
| void |
| runtime·SysUnused(void *v, uintptr n) |
| { |
| USED(v, n); |
| } |
| |
| void |
| runtime·SysMemInit(void) |
| { |
| } |
