Fix quadratic CL asm parsing

lib/asm-cl.js

@@ -123,10 +123,22 @@ ClParser.prototype._add = function (obj) {
         obj.opcodes = this.opcoder.opcodes;
         obj.address = this.opcoder.offset;
     }
+    if (obj.keep) {
+        this.markUsed(obj.lineLabels);
+    }
     this.result.push(obj);
     debug(obj);
 };
 
+ClParser.prototype.markUsed = function (lineLabels) {
+    _.each(lineLabels, function (val, label) {
+        if (!this.labels[label]) {
+            debug("Marking " + label + " as used");
+        }
+        this.labels[label] = true;
+    }, this);
+};
+
 ClParser.prototype.addLine = function (line) {
     if (!!line.match(ignoreAll)) return;
     line = this.opcoder.onLine(line);
@@ -156,12 +168,12 @@ ClParser.prototype.addLine = function (line) {
     var isIndented = match[1] !== "";
     var command = match[2];
     var comment = match[3] || "";
+    var lineLabels = {};
+    _.each(command.match(labelFind), function (label) {
+        lineLabels[label] = true;
+    }, this);
     if (isIndented && this.opcoder.hasOpcodes()) {
-        this._add({keep: true, text: "  " + command + comment, source: this.source});
-        match = command.match(labelFind);
-        _.each(match, function (label) {
-            this.labels[label] = true;
-        }, this);
+        this._add({keep: true, lineLabels: lineLabels, text: "  " + command + comment, source: this.source});
     } else {
         var keep = !this.filters.directives;
         if (command.match(isProc))
@@ -183,28 +195,32 @@ ClParser.prototype.addLine = function (line) {
             debug(match, this.currentLabel);
             tempDef = true;
         }
-        this._add({keep: keep, text: command + comment, source: null});
+        this._add({keep: keep, lineLabels: lineLabels, text: command + comment, source: null});
         if (tempDef) this.currentLabel = null;
     }
 };
 
-ClParser.prototype.findUsed = function () {
-    // TODO: quadratic!
+ClParser.prototype.findUsedInternal = function () {
     var changed = false;
-    var findUsedInternal = function (key, label) {
-        _.each(this.result, function (obj) {
-            if (!obj.keep && obj.label == label) {
-                debug("Keeping", obj, "due to", label);
-                obj.keep = true;
-                changed = true;
-            }
-        }, this);
-    };
+    _.each(this.result, function (obj) {
+        if (obj.keep || !this.labels[obj.label]) {
+            return;
+        }
+        debug("Keeping", obj);
+        obj.keep = true;
+        this.markUsed(obj.lineLabels);
+        changed = true;
+    }, this);
+    debug("changed", changed);
+    return changed;
+};
+
+ClParser.prototype.findUsed = function () {
+    // TODO write tests that cover dependent labels being used.
     var MaxIterations = 100;
     for (var i = 0; i < MaxIterations; ++i) {
-        changed = false;
-        _.each(this.labels, findUsedInternal, this);
-        if (!changed) return;
+        if (!this.findUsedInternal())
+            return;
     }
 };