minix/lib/libm2/load.c
2005-04-21 14:53:53 +00:00

46 lines
989 B
C
Executable file

/*
(c) copyright 1988 by the Vrije Universiteit, Amsterdam, The Netherlands.
See the copyright notice in the ACK home directory, in the file "Copyright".
*/
/*
Module: get value on stack, byte by byte
Author: Ceriel J.H. Jacobs
Version: $Header$
*/
#include <m2_traps.h>
#ifndef EM_WSIZE
#define EM_WSIZE _EM_WSIZE
#define EM_PSIZE _EM_PSIZE
#endif
#if EM_WSIZE==EM_PSIZE
typedef unsigned pcnt;
#else
typedef long pcnt;
#endif
load(siz, addr, p)
register char *addr;
register pcnt siz;
{
/* Make sure, that a value with a size that could have been
handled by the LOI instruction ends up at the same place,
where it would, were the LOI instruction used.
*/
register char *q = (char *) &p;
char t[4];
if (siz < EM_WSIZE && EM_WSIZE % siz == 0) {
/* as long as EM_WSIZE <= 4 ... */
if (siz != 2) TRP(M2_INTERNAL); /* internal error */
q = &t[0];
}
while (siz--) *q++ = *addr++;
if (q - t == 2) {
*((unsigned *)(&p)) = *((unsigned short *) (&t[0]));
}
}