view lwasm/pass2.c @ 556:928c033c0cd0

Allow MOD directive to accept only the standard base header parameters There are cases where only the standard OS9 module header fields are to be provided. This could be, for instance, in the case of a nonstandard user type module. So allow the execution offset and data size fields to be omitted entirely and handle the module length correctly as well.
author William Astle <lost@l-w.ca>
date Fri, 08 Sep 2023 00:32:40 -0600
parents 8764142b3192
children
line wrap: on
line source

/*
pass2.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"

/*
pass 2: deal with undefined symbols and do a simplification pass
on all the expressions. Handle PRAGMA_IMPORTUNDEFEXPORT

*/
void do_pass2(asmstate_t *as)
{
	line_t *cl;
	exportlist_t *ex;
	struct symtabe *s;
	importlist_t *im;
	struct line_expr_s *le;

	// verify the export list
	if (as -> output_format == OUTPUT_OBJ)
	{	
		for (ex = as -> exportlist; ex; ex = ex -> next)
		{
			s = lookup_symbol(as, NULL, ex -> symbol);
			if (!s)
			{
				if (CURPRAGMA(ex -> line, PRAGMA_IMPORTUNDEFEXPORT))
				{
					for (im = as -> importlist; im; im = im -> next)
					{
						if (!strcmp(ex -> symbol, im -> symbol))
							break;
					}
					if (!im)
					{
						im = lw_alloc(sizeof(importlist_t));
						im -> symbol = lw_strdup(ex -> symbol);
						im -> next = as -> importlist;
						as -> importlist = im;
					}
				}
				else
				{
					// undefined export - register error
					lwasm_register_error(as, ex->line, E_SYMBOL_UNDEFINED_EXPORT);
				}
			}
			ex -> se = s;
		}
		if (as -> errorcount > 0)
			return;
	}

	// we want to throw errors on undefined symbols here
	as -> badsymerr = 1;
	
	// now do some reductions on expressions
	for (cl = as -> line_head; cl; cl = cl -> next)
	{
		as -> cl = cl;
		
		// simplify address
		lwasm_reduce_expr(as, cl -> addr);

		// simplify data address
		lwasm_reduce_expr(as, cl -> daddr);
		
		// simplify each expression
		for (le = cl -> exprs; le; le = le -> next)
			lwasm_reduce_expr(as, le -> expr);
	}	
}