diff lwasm/insn_gen.c @ 402:b20f14edda5a

Completed initial conversion to new parser allowing spaces in operands Converted the remaining addressing modes. This required a complete rewrite of a large portion of the indexed addressing parser. Now the entire indexed parsing system is programmatic without cheating with a lookup table. This update also fixes the "force 0,r" by writing a literal 0,r which is *supposed* to work. There will likely be some pseudo ops that need tweaking for space handling, specially those that take multiple operands of some description which are not expressions. (The expression parser call eats the spaces both before and after the expression, if appropriate.)
author William Astle <lost@l-w.ca>
date Wed, 14 Oct 2015 20:49:41 -0600
parents 2d9b7ae6c329
children 3948c874901b
line wrap: on
line diff
--- a/lwasm/insn_gen.c	Wed Oct 14 19:15:41 2015 -0600
+++ b/lwasm/insn_gen.c	Wed Oct 14 20:49:41 2015 -0600
@@ -37,36 +37,35 @@
 // "extra" is required due to the way OIM, EIM, TIM, and AIM work
 void insn_parse_gen_aux(asmstate_t *as, line_t *l, char **p, int elen)
 {
-	const char *optr2;
+	char *optr2;
 	int v1, tv;
 	lw_expr_t s;
-
+	
 	if (!**p)
 	{
 		lwasm_register_error(as, l, E_OPERAND_BAD);
 		return;
 	}
 
-	optr2 = *p;
-	while (*optr2 && !isspace(*optr2) && *optr2 != ',') optr2++
-		/* do nothing */ ;
-
-	if (*optr2 == ',' || **p == '[')
+	/* this is the easy case - start it [ or , means indexed */
+	if (**p == ',' || **p == '[')
 	{
+indexed:
 		l -> lint = -1;
-		l -> lint2 = 1;
+		l -> lint2  = 1;
 		insn_parse_indexed_aux(as, l, p);
 		l -> minlen = OPLEN(instab[l -> insn].ops[1]) + 1 + elen;
 		l -> maxlen = OPLEN(instab[l -> insn].ops[1]) + 3 + elen;
 		goto out;
 	}
 
+	/* we have to parse the first expression to find if we have a comma after it */
+	optr2 = *p;
 	if (**p == '<')
 	{
 		(*p)++;
 		l -> lint2 = 0;
 	}
-
 	// for compatibility with asxxxx
 	// * followed by a digit, alpha, or _, or ., or ?, or another * is "f8"
 	else if (**p == '*')
@@ -87,10 +86,17 @@
 	{
 		l -> lint2 = -1;
 	}
-
-	l -> minlen = OPLEN(instab[l -> insn].ops[0]) + 1 + elen;
-	l -> maxlen = OPLEN(instab[l -> insn].ops[2]) + 2 + elen;
+	lwasm_skip_to_next_token(l, p);
+	
 	s = lwasm_parse_expr(as, p);
+	
+	if (**p == ',')
+	{
+		/* we have an indexed mode here - reset and transfer control to indexing mode */
+		lw_expr_destroy(s);
+		*p = optr2;
+		goto indexed;
+	}
 	if (!s)
 	{
 		lwasm_register_error(as, l, E_OPERAND_BAD);
@@ -99,6 +105,8 @@
 	
 	lwasm_save_expr(l, 0, s);
 
+	l -> minlen = OPLEN(instab[l -> insn].ops[0]) + 1 + elen;
+	l -> maxlen = OPLEN(instab[l -> insn].ops[2]) + 2 + elen;
 	if (as -> output_format == OUTPUT_OBJ && l -> lint2 == -1)
 	{
 		l -> lint2 = 2;