view lwasm/pass2.c @ 370:8764142b3192

Convert internal error/warning handling framework to a new unified system Replace the ad hoc error and warning handling with a new system that codifies the errors with specific codes. This makes it possible in the future for error numbers to be used for testing and other purposes. It also makes sure the error strings themselves are consistent. Thanks to Erik G <erik@6809.org> for the patch.
author William Astle <lost@l-w.ca>
date Mon, 22 Jun 2015 18:49:38 -0600
parents 697bc543368c
children
line wrap: on
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/*
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);
	}	
}