/* Copyright (c) 1984 Regents of the University of California */

#ifndef lint
static char sccsid[] = "@(#)machdep.c	1.2	(Berkeley)	08/19/84";
#endif not lint

#include <stdio.h>
#include <ctype.h>

/*
 * The routines in this file must be rewritten for each
 * new machine that this program is ported to.
 */

/*
 * Check to see if a line is a candidate for replacement.
 * Return pointer to name to be looked up in pattern table.
 */
char *
doreplaceon(cp)
	char *cp;
{

	if (bcmp(cp, "calls\t$", 7) == 0)
		return (cp + 7);
	return (0);
}

/*
 * Find the next argument to the function being expanded.
 * MACHINE DEPENDENT
 */
nextarg(argc, argv)
	int argc;
	char *argv[];
{
	register char *lastarg = argv[2];

	if (argc == 3 &&
	    bcmp(argv[0], "mov", 3) == 0 &&
	    bcmp(argv[1], "(sp)+", 6) == 0 &&
	    lastarg[0] == 'r' && isdigit(lastarg[1]) && lastarg[2] == '\0')
		return (lastarg[1] - '0');
	return (-1);
}

/*
 * Determine whether the current line pushes an argument.
 * MACHINE DEPENDENT
 */
 ispusharg(argc, argv)
	int argc;
	char *argv[];
{

	if (argc < 2)
		return (0);
	if (argc == 2 && bcmp(argv[0], "push", 4) == 0)
		return (1);
	if (bcmp(argv[argc - 1], "-(sp)", 6) == 0)
		return (1);
	return (0);
}

/*
 * Determine which (if any) registers are modified
 * Return register number that is modified, -1 if none are modified.
 * MACHINE DEPENDENT
 */
modifies(argc, argv)
	int argc;
	char *argv[];
{
	/*
	 * For the VAX all we care about are r0 to r5
	 */
	register char *lastarg = argv[argc - 1];

	if (lastarg[0] == 'r' && isdigit(lastarg[1]) && lastarg[2] == '\0')
		return (lastarg[1] - '0');
	return (-1);
}

/*
 * Rewrite the instruction in (argc, argv) to store its
 * contents into arg instead of onto the stack. The new
 * instruction is placed in the buffer that is provided.
 * MACHINE DEPENDENT
 */
rewrite(instbuf, argc, argv, target)
	char *instbuf;
	int argc;
	char *argv[];
	int target;
{

	switch (argc) {
	case 0:
		instbuf[0] = '\0';
		fprintf("blank line to rewrite?\n");
		return;
	case 1:
		sprintf(instbuf, "\t%s\n", argv[0]);
		fprintf(stderr, "rewrite?-> %s", instbuf);
		return;
	case 2:
		if (bcmp(argv[0], "push", 4) == 0) {
			sprintf(instbuf, "\tmov%s\t%s,r%d\n",
				&argv[0][4], argv[1], target);
			return;
		}
		sprintf(instbuf, "\t%s\tr%d\n", argv[0], target);
		return;
	case 3:
		sprintf(instbuf, "\t%s\t%s,r%d\n", argv[0], argv[1], target);
		return;
	case 4:
		sprintf(instbuf, "\t%s\t%s,%s,r%d\n",
			argv[0], argv[1], argv[2], target);
		return;
	case 5:
		sprintf(instbuf, "\t%s\t%s,%s,%s,r%d\n",
			argv[0], argv[1], argv[2], argv[3], target);
		return;
	default:
		sprintf(instbuf, "\t%s\t%s", argv[0], argv[1]);
		argc -= 2, argv += 2;
		while (argc-- > 0) {
			strcat(instbuf, ",");
			strcat(instbuf, *argv++);
		}
		strcat(instbuf, "\n");
		fprintf(stderr, "rewrite?-> %s", instbuf);
		return;
	}
}