scc

commit 3cfe5e81491c46ec77110bd2a05280cd1e10d237
parent ff136f0ec39799a447752a1736173c4fa86917ab
Author: Roberto E. Vargas Caballero <k0ga@shike2.com>
Date:   Sat,  9 Sep 2017 21:09:37 +0200

[as] Add symbol type

Diffstat:
M
as/as.h
 | 
18
++++++++++++++++++
M
as/emit.c
 | 
35
+++++++++++++++++++++++++++++++++++

2 files changed, 53 insertions(+), 0 deletions(-)
diff --git a/as/as.h b/as/as.h
@@ -5,6 +5,14 @@ enum secflags {
 	SFILE,
 };
 
+enum symflags {
+	FUNDEF  = 'U',
+	FABS    = 'A',
+	FCOMMON = 'C',
+	FBSS    = 'B',
+	FDATA   = 'D',
+};
+
 enum args {
 	AIMM = 1,
 	AMAX,
@@ -21,6 +29,7 @@ typedef struct op Op;
 typedef struct arg Arg;
 typedef void Format(Op *, Arg *);
 typedef struct section Section;
+typedef struct symbol Symbol;
 
 struct line {
 	char *label;
@@ -57,6 +66,14 @@ struct section {
 	struct section *next;
 };
 
+struct symbol {
+	char *name;
+	char type;
+	short desc;
+	TUINT value;
+	struct symbol *next;
+};
+
 extern void isections(void);
 extern void writeout(char *name);
 extern void emit(Section *sec, char *bytes, int nbytes);
@@ -65,6 +82,7 @@ extern void incpc(int siz);
 extern char *pack(TUINT v, int n, int inc);
 extern void error(char *msg, ...);
 extern Arg *getargs(char *s);
+extern Symbol *lookup(char *name);
 
 /* Avoid errors in files where stdio is not included */
 #ifdef stdin
diff --git a/as/emit.c b/as/emit.c
@@ -6,6 +6,8 @@
 #include "../inc/scc.h"
 #include "as.h"
 
+#define HASHSIZ 64
+
 static Section abss = {
 	.name = "abs",
 	.flags = SREAD|SWRITE
@@ -33,6 +35,39 @@ Section *cursec = &text, *headp = &text;
 
 int pass;
 
+static Symbol *hashtbl[HASHSIZ];
+
+Symbol *
+lookup(char *name)
+{
+	unsigned h;
+	Symbol *sym;
+	int c;
+	char *t, *s;
+
+	s = name;
+	for (h = 0; c = *s; ++s)
+		h = h*33 ^ c;
+	h &= HASHSIZ-1;
+
+	c = *name;
+	for (sym = hashtbl[h]; sym; sym = sym->next) {
+		t = sym->name;
+		if (c == *t && !strcmp(t, name))
+			return sym;
+	}
+
+	sym = xmalloc(sizeof(sym));
+	sym->name = xstrdup(name);
+	sym->type = FUNDEF;
+	sym->desc = 0;
+	sym->value = 0;
+	sym->next = hashtbl[h];
+	hashtbl[h] = sym;
+
+	return sym;
+}
+
 char *
 pack(TUINT v, int n, int inc)
 {