Subversion Repositories planix.SVN

Rev

Rev 2 | Details | Compare with Previous | Last modification | View Log | RSS feed

Rev Author Line No. Line
2 - 1 
#include "u.h"
2 
#include "libc.h"
3 
 
4 
int
5 
tas(long *x)
6 
{
7 
	int     v;
8 
 
9 
	__asm__(	"movl   $1, %%eax\n\t"
10 
				"xchgl  %%eax,(%%rcx)"
11 
				: "=a" (v)
12 
				: "c" (x)
13 
	);
14 
	switch(v) {
15 
	case 0:
16 
	case 1:
17 
		return v;
18 
	default:
19 
		print("canlock: corrupted 0x%lux\n", v);
20 
		return 1;
21 
	}
22 
}
23