view lwasm/pass6.c @ 389:2d9b7ae6c329

Throw error if address overflows in extended mode This may or may not cause extra problems due to sloppiness in dealing with calculations that overflow in 16 bits. However, presumably it is a good idea so unless something major pops up, it seems like a good idea. Thanks to Erik G <erik@6809.org> for the patch.
author William Astle <lost@l-w.ca>
date Mon, 13 Jul 2015 21:37:49 -0600
parents 8764142b3192
children 58cafa61ab40
line wrap: on
line source

/*
pass6.c

Copyright © 2010 William Astle

This file is part of LWTOOLS.

LWTOOLS is free software: you can redistribute it and/or modify it under the
terms of the GNU General Public License as published by the Free Software
Foundation, either version 3 of the License, or (at your option) any later
version.

This program is distributed in the hope that it will be useful, but WITHOUT
ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
more details.

You should have received a copy of the GNU General Public License along with
this program. If not, see <http://www.gnu.org/licenses/>.
*/

#include <stdio.h>
#include <string.h>

#include <lw_alloc.h>
#include <lw_string.h>

#include "lwasm.h"
#include "instab.h"

/*
Finalize Pass

Reduce all expressions in a final pass.

Observation:

Everything should reduce as far as it is going to in a single pass
because all line addresses are now constant (or section-base offset)
*/

static int exprok_aux(lw_expr_t e, void *priv)
{
	asmstate_t *as = priv;
	
	if (lw_expr_istype(e, lw_expr_type_int))
		return 0;
	
	if (as -> output_format == OUTPUT_OBJ)
	{
		if (lw_expr_istype(e, lw_expr_type_oper))
			return 0;
		if (lw_expr_istype(e, lw_expr_type_special) && as -> output_format == OUTPUT_OBJ)
		{
			int t;
			t = lw_expr_specint(e);
			if (t == lwasm_expr_secbase || t == lwasm_expr_syment || t == lwasm_expr_import)
				return 0;
		}
	}
	
	return 1;
}

static int exprok(asmstate_t *as, lw_expr_t e)
{
	if (lw_expr_testterms(e, exprok_aux, as))
		return 0;
	return 1;
}


void do_pass6(asmstate_t *as)
{
	line_t *cl;
	struct line_expr_s *le;

	for (cl = as -> line_head; cl; cl = cl -> next)
	{
		as -> cl = cl;
		for (le = cl -> exprs; le; le = le -> next)
		{
			lwasm_reduce_expr(as, le -> expr);
			if (!exprok(as, le -> expr))
			{
				lwasm_register_error2(as, cl, E_EXPRESSION_BAD, "%s", lw_expr_print(le -> expr));
			}
		}
	}
}