diff lwasm/pass5.c @ 0:2c24602be78f

Initial import from lwtools 3.0.1 version, with new hand built build system and file reorganization
author lost@l-w.ca
date Wed, 19 Jan 2011 22:27:17 -0700
parents
children 7317fbe024af
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--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lwasm/pass5.c	Wed Jan 19 22:27:17 2011 -0700
@@ -0,0 +1,119 @@
+/*
+pass5.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"
+
+/*
+AssignAddresses Pass
+
+Force resolution of all line addresses
+
+*/
+
+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 (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)
+			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_pass5(asmstate_t *as)
+{
+	int rc;
+	int cnt;
+	int ocnt;
+	line_t *cl, *sl;
+	struct line_expr_s *le;
+
+	// first, count the number of non-constant addresses; do
+	// a reduction first on each one
+	for (cnt = 0, cl = as -> line_head; cl; cl = cl -> next)
+	{
+		as -> cl = cl;
+		lwasm_reduce_expr(as, cl -> addr);
+		if (!exprok(as, cl -> addr))
+			cnt++;
+	}
+
+	sl = as -> line_head;
+	while (cnt > 0)
+	{
+		ocnt = cnt;
+		
+		// find an unresolved address
+		for ( ; sl && exprok(as, sl -> addr); sl = sl -> next)
+			/* do nothing */ ;
+
+		// simplify address
+		for (cl = sl; cl; cl = cl -> next)
+		{
+			as -> cl = sl;
+			lwasm_reduce_expr(as, sl -> addr);
+		
+			if (exprok(as, cl -> addr))
+			{
+				if (0 == --cnt);
+					return;
+			}
+		}
+		
+		if (cnt == ocnt)
+			break;
+	}
+	
+	if (cnt)
+	{
+		// we have non-resolved line addresses here
+		for (cl = sl; cl; cl = cl -> next)
+		{
+			if (!exprok(as, cl -> addr))
+			{
+				lwasm_register_error(as, cl, "Cannot resolve line address");
+			}
+		}
+	}
+}