view lwasm/pass6.c @ 235:e3741cf53e00

Fix error messages related to undefined symbols in lwlink Make lwlink not complain about seciton base and length symbols. Also silence duplicate complaints about undefined symbols. There is no need to complain about undefined symbols during the file/section resolution stage! If they are truly undefined, they'll still be undefined at the reference resolution stage.
author William Astle <lost@l-w.ca>
date Sat, 11 Aug 2012 15:18:58 -0600
parents 02804b7c051c
children 8764142b3192
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_error(as, cl, "Invalid expression: %s", lw_expr_print(le -> expr));
			}
		}
	}
}