scc

commit 9097ba1b790c0387f2d6fc6d3a99ec2b98f97679
parent 605e945e14e16e7a8d9855a8fc49749a48a0c6db
Author: Roberto E. Vargas Caballero <k0ga@shike2.com>
Date:   Fri, 22 Sep 2017 08:43:16 +0200

[as] Remove Arg type

We only need an array of Node* because this is what the expression
evaluator is returning.

Diffstat:
M
as/as.h
 | 
12
+++---------
M
as/ins.c
 | 
22
++++++++++++----------
M
as/main.c
 | 
6
+++---
M
as/parser.c
 | 
44
+++++++++++---------------------------------

4 files changed, 29 insertions(+), 55 deletions(-)
diff --git a/as/as.h b/as/as.h
@@ -39,11 +39,10 @@ enum endianess {
 
 typedef struct ins Ins;
 typedef struct op Op;
-typedef struct arg Arg;
-typedef void Format(Op *, Arg *);
 typedef struct section Section;
 typedef struct symbol Symbol;
 typedef struct node Node;
+typedef void Format(Op *, Node **);
 
 struct line {
 	char *label;
@@ -59,16 +58,11 @@ struct ins {
 struct op {
 	unsigned char flags;
 	char size;
-	void (*format)(Op *, Arg *);
+	void (*format)(Op *, Node **);
 	char *bytes;
 	unsigned char *args;
 };
 
-struct arg {
-	unsigned char type;
-	TUINT val;
-};
-
 struct section {
 	char *name;
 	char *mem;
@@ -110,7 +104,7 @@ extern Symbol *lookup(char *name);
 extern Symbol *deflabel(char *name);
 
 /* parser.c */
-extern Arg *getargs(char *s);
+extern Node **getargs(char *s);
 extern void error(char *msg, ...);
 /* Avoid errors in files where stdio is not included */
 #ifdef stdin
diff --git a/as/ins.c b/as/ins.c
@@ -4,47 +4,49 @@ static char sccsid[] = "@(#) ./as/ins.c";
 #include "as.h"
 
 void
-direct(Op *op, Arg *args)
+direct(Op *op, Node **args)
 {
 	emit(cursec, op->bytes, op->size);
 }
 
 void
-def(Arg *args, int siz)
+def(Node **args, int siz)
 {
-	for ( ; args->type; ++args)
-		emit(cursec, pack(args->val, siz, endian), siz);
+	Node *np;
+
+	for ( ; np = *args; ++args)
+		emit(cursec, pack(np->sym->value, siz, endian), siz);
 }
 
 void
-defb(Op *op, Arg *args)
+defb(Op *op, Node **args)
 {
 	def(args, 1);
 }
 
 void
-defw(Op *op, Arg *args)
+defw(Op *op, Node **args)
 {
 	def(args, 2);
 }
 
 void
-defd(Op *op, Arg *args)
+defd(Op *op, Node **args)
 {
 	def(args, 4);
 }
 
 void
-defq(Op *op, Arg *args)
+defq(Op *op, Node **args)
 {
 	def(args, 8);
 }
 
 void
-equ(Op *op, Arg *args)
+equ(Op *op, Node **args)
 {
 	if (!linesym)
 		error("label definition lacks a label");
 	else
-		linesym->value = args->val;
+		linesym->value = (*args)->sym->value;
 }
diff --git a/as/main.c b/as/main.c
@@ -8,7 +8,7 @@ static char sccsid[] = "@(#) ./as/main.c";
 #include "as.h"
 
 int
-match(Op *op, Arg *args)
+match(Op *op, Node **args)
 {
 	return 1;
 }
@@ -26,8 +26,8 @@ as(char *text, char *xargs)
 {
 	Ins *ins;
 	Op *op, *lim;
-	Arg *args;
-	
+	Node **args;
+
 	ins = bsearch(text, instab, nr_ins, sizeof(Ins), cmp);
 	if (!ins) {
 		error("invalid instruction");
diff --git a/as/parser.c b/as/parser.c
@@ -32,55 +32,33 @@ error(char *msg, ...)
 		die("as: too many errors");
 }
 
-static Arg
-number(char *s, int base)
-{
-	Arg arg;
-	TUINT n;
-
-	/* TODO: Check overflow here */
-	arg.type = AIMM;
-	for (n = 0; *s; n += *s++ - '0')
-		n *= base;
-	arg.val = n;
-
-	return arg;
-}
-
-Arg *
+Node **
 getargs(char *s)
 {
 	char *t;
 	int ch, len;
-	Arg *ap;
-	static Arg args[NARGS];
+	Node **ap;
+	static Node *args[NARGS];
 
-	for (ap = args; s; ++ap) {
+	if (!s)
+		return NULL;
+
+	for (ap = args; ; *ap++ = expr(t)) {
 		while (isspace(*s))
 			++s;
 		if (*s == '\0')
 			break;
 		if (ap == &args[NARGS-1])
-			die("too many arguments in one instruction");
+			error("too many arguments in one instruction");
 
 		for (t = s; *s && *s != ','; s++)
 			/* nothing */;
+		*s++ = '\0';
 		len = t - s;
 		if (len == 0)
-			goto wrong_operand;
-
-		if (*s)
-			*s++ = '\0';
-
-		ch = *t;
-		if (isdigit(ch)) {
-			*ap = number(t, (s[len-1] == 'H') ? 16 : 10);
-			continue;
-		}
-wrong_operand:
-		error("wrong operand '%s'", t);
+			error("wrong operand '%s'", t);
 	}
-	ap->type = 0;
+	*ap = NULL;
 
 	return args;
 }