Faster sublabel detection

src/uxnasm.c

@@ -36,13 +36,14 @@ typedef struct {
 typedef struct {
 	Uint8 data[LENGTH];
 	Uint8 lambda_stack[0x100], lambda_ptr, lambda_len;
-	Uint16 ptr, length, label_len, macro_len, refs_len;
+	Uint16 ptr, line, length, label_len, macro_len, refs_len;
 	char scope[0x40], lambda_name[0x05], *location;
 	Label labels[0x400];
 	Macro macros[0x100];
 	Reference refs[0x1000];
 } Program;
 
+char sublabel[0x40];
 char token[0x40];
 
 Program p;
@@ -70,6 +71,7 @@ static char *scat(char *dst, const char *src) { char *ptr = dst + slen(dst); whi
 /* clang-format on */
 
 static int parse(char *w, FILE *f);
+static char *makesublabel(char *src, char *scope, char *name);
 
 static int
 error_top(const char *name, const char *msg)
@@ -81,7 +83,7 @@ error_top(const char *name, const char *msg)
 static int
 error_asm(const char *name)
 {
-	fprintf(stderr, "%s: %s in @%s, %s:%d.\n", name, token, p.scope, p.location, 123);
+	fprintf(stderr, "%s: %s in @%s, %s:%d.\n", name, token, p.scope, p.location, p.line);
 	return 0;
 }
 
@@ -89,6 +91,7 @@ static char *
 setlocation(char *name)
 {
 	p.location = name;
+	p.line = 0;
 	return name;
 }
 
@@ -106,6 +109,8 @@ static Label *
 findlabel(char *name)
 {
 	int i;
+	if(name[0] == '&')
+		name = makesublabel(sublabel, p.scope, name + 1);
 	for(i = 0; i < p.label_len; i++)
 		if(scmp(p.labels[i].name, name, 0x40))
 			return &p.labels[i];
@@ -205,19 +210,34 @@ makelambda(int id)
 }
 
 static char *
-makesublabel(char *src, char *scope, char *name)
+makesublabel(char *buf, char *scope, char *name)
 {
 	if(slen(scope) + slen(name) >= 0x3f) {
 		error_asm("Sublabel length too long");
 		return NULL;
 	}
-	return scat(scat(scpy(scope, src, 0x40), "/"), name);
+	return scat(scat(scpy(scope, buf, 0x40), "/"), name);
+}
+
+static int
+makepad(char *w)
+{
+	Label *l;
+	int rel = w[0] == '$' ? p.ptr : 0;
+	if(sihx(w + 1))
+		p.ptr = shex(w + 1) + rel;
+	else {
+		if(!(l = findlabel(w + 1)))
+			return error_asm("Invalid label");
+		p.ptr = l->addr + rel;
+	}
+	return 1;
 }
 
 static int
 addref(char *scope, char *label, char rune, Uint16 addr)
 {
-	char subw[0x40], parent[0x40];
+	char parent[0x40];
 	Reference *r;
 	if(p.refs_len >= 0x1000)
 		return error_asm("References limit exceeded");
@@ -226,9 +246,8 @@ addref(char *scope, char *label, char rune, Uint16 addr)
 		p.lambda_stack[p.lambda_ptr++] = p.lambda_len;
 		scpy(makelambda(p.lambda_len++), r->name, 0x40);
 	} else if(label[0] == '&' || label[0] == '/') {
-		if(!makesublabel(subw, scope, label + 1))
+		if(!makesublabel(r->name, scope, label + 1))
 			return error_asm("Invalid sublabel");
-		scpy(subw, r->name, 0x40);
 	} else {
 		int pos = spos(label, '/');
 		if(pos > 0) {
@@ -282,10 +301,7 @@ parse(char *w, FILE *f)
 {
 	int i;
 	char word[0x40], subw[0x40], c;
-	Label *l;
 	Macro *m;
-	if(slen(w) >= 63)
-		return error_asm("Invalid token");
 	switch(w[0]) {
 	case '(': /* comment */
 		if(slen(w) != 1) fprintf(stderr, "-- Malformed comment: %s\n", w);
@@ -307,31 +323,10 @@ parse(char *w, FILE *f)
 		if(!makemacro(w + 1, f))
 			return error_asm("Invalid macro");
 		break;
-	case '|': /* pad-absolute */
-		if(sihx(w + 1))
-			p.ptr = shex(w + 1);
-		else if(w[1] == '&') {
-			if(!makesublabel(subw, p.scope, w + 2) || !(l = findlabel(subw)))
-				return error_asm("Invalid sublabel");
-			p.ptr = l->addr;
-		} else {
-			if(!(l = findlabel(w + 1)))
-				return error_asm("Invalid label");
-			p.ptr = l->addr;
-		}
-		break;
 	case '$': /* pad-relative */
-		if(sihx(w + 1))
-			p.ptr += shex(w + 1);
-		else if(w[1] == '&') {
-			if(!makesublabel(subw, p.scope, w + 2) || !(l = findlabel(subw)))
-				return error_asm("Invalid sublabel");
-			p.ptr += l->addr;
-		} else {
-			if(!(l = findlabel(w + 1)))
-				return error_asm("Invalid label");
-			p.ptr += l->addr;
-		}
+	case '|': /* pad-absolute */
+		if(!makepad(w))
+			return error_asm("Invalid padding");
 		break;
 	case '@': /* label */
 		if(!makelabel(w + 1))
@@ -456,11 +451,25 @@ resolve(void)
 static int
 assemble(FILE *f)
 {
+	unsigned int buf;
+	char *cptr = token;
 	p.ptr = 0x100;
 	scpy("on-reset", p.scope, 0x40);
-	while(fscanf(f, "%62s", token) == 1)
-		if(slen(token) > 0x3d || !parse(token, f))
-			return error_asm("Invalid token");
+	while(fread(&buf, 1, 1, f)) {
+		char c = (char)buf;
+		if(c < 0x21) {
+			*cptr++ = 0x00;
+			if(c == 0x0a)
+				p.line++;
+			if(token[0])
+				if(!parse(token, f))
+					return 0;
+			cptr = token;
+		} else if(cptr - token < 0x3f)
+			*cptr++ = c;
+		else
+			return error_asm("Token too long");
+	}
 	return resolve();
 }