Added a bunch of filters to the assembly output

static/asm.js

@@ -47,3 +47,35 @@ CodeMirror.defineMode("asm", function() {
 });
 
 CodeMirror.defineMIME("text/x-asm", "asm");
+
+function filterAsm(asm, filters) {
+    var result = [];
+    var asmLines = asm.split("\n");
+    var labelsUsed = {};
+    var labelFind = /\.[a-zA-Z0-9$_.]+/g;
+    $.each(asmLines, function(_, line) {
+        if (line == "" || line[0] == ".") return;
+        var match = line.match(labelFind);
+        if (match) $.each(match, function(_, label) { labelsUsed[label] = true; });
+    });
+    var directive = /^\s*\..*$/;
+    var labelDefinition = /^(\.[a-zA-Z0-9$_.]+):/;
+    var commentOnly = /^\s*#.*/;
+    $.each(asmLines, function(_, line) {
+        if (line.trim() == "") return;
+        if (filters.commentOnly && line.match(commentOnly)) return;
+        var match = line.match(labelDefinition);
+        if (match && labelsUsed[match[1]] == undefined) {
+            if (filters.labels) return;
+        }
+        if (!match && filters.directives) {
+            // Check for directives only if it wasn't a label; the regexp would
+            // otherwise misinterpret labels as directives.
+            match = line.match(directive);
+            if (match) return;
+        }
+        result.push(line);
+    });
+    return result.join("\n");
+}
+

static/gcc.js

@@ -26,6 +26,7 @@ var pendingTimeout = null;
 var asmCodeMirror = null;
 var cppEditor = null;
 var lastRequest = null;
+var currentAssembly = null;
 
 function parseLines(lines, callback) {
     var re = /^\<stdin\>:([0-9]+):([0-9]+):\s+(.*)/;
@@ -68,7 +69,13 @@ function onCompileResponse(data) {
             elem.text(msg);
         }
     });
-    asmCodeMirror.setValue(data.asm || "[no output]");
+    currentAssembly = data.asm || "[no output]";
+    updateAsm();
+}
+
+function updateAsm() {
+    if (!currentAssembly) return;
+    asmCodeMirror.setValue(filterAsm(currentAssembly, getAsmFilters()));
 }
 
 function onChange() {
@@ -91,6 +98,8 @@ function onChange() {
             success: onCompileResponse});
     }, 750);
     window.localStorage['code'] = cppEditor.getValue();
+    window.localStorage['filter'] = JSON.stringify(getAsmFilters());
+    updateAsm();
     $('a.permalink').attr('href', '#' + serialiseState());
 }
 
@@ -191,10 +200,11 @@ function saveFileAs() {
 
 function serialiseState() {
     var state = {
-        version: 1,
+        version: 2,
         source: cppEditor.getValue(),
         compiler: $('.compiler').val(),
-        options: $('.compiler_options').val()
+        options: $('.compiler_options').val(),
+        filterAsm: getAsmFilters()
     };
     return encodeURIComponent(JSON.stringify(state));
 }
@@ -202,11 +212,13 @@ function serialiseState() {
 function deserialiseState(state) {
     try {
         var state = $.parseJSON(decodeURIComponent(state));
-        if (state.version != 1) return false;
+        if (state.version == 1) { state.filterAsm = true; }
+        else if (state.version != 2) return false;
     } catch (ignored) { return false; }
     cppEditor.setValue(state.source);
     $('.compiler').val(state.compiler);
     $('.compiler_options').val(state.options);
+    setFilterUi(state.filterAsm);
     return true;
 }
 
@@ -261,6 +273,11 @@ function initialise() {
         return false;
     });
     
+    $('.filter button.btn').click(function(e) {
+        $(e.target).toggleClass('active');
+        onChange();
+    });
+
     $(window).bind('hashchange', function() {
         deserialiseState(window.location.hash.substr(1));
     });
@@ -270,6 +287,21 @@ function initialise() {
     }
     if (window.localStorage['code']) cppEditor.setValue(window.localStorage['code']);
     if (window.localStorage['compilerOptions']) $('.compiler_options').val(window.localStorage['compilerOptions']);
+    setFilterUi($.parseJSON(window.localStorage['filter'] || "{}"));
+}
+
+function getAsmFilters() {
+    var asmFilters = {};
+    $('.filter button.btn.active').each(function() {
+        asmFilters[$(this).val()] = true;
+    });
+    return asmFilters;
+}
+
+function setFilterUi(asmFilters) {
+    $('.filter button.btn').each(function() {
+        $(this).toggleClass('active', !!asmFilters[$(this).val()]);
+    });
 }
 
 $(initialise);

static/index.html

@@ -12,7 +12,6 @@
         <script src="gcc.js"></script>
         <script src="ext/bootstrap/js/bootstrap.js"></script>
 <script type="text/javascript">
-
   var _gaq = _gaq || [];
   _gaq.push(['_setAccount', 'UA-55180-6']);
   _gaq.push(['_trackPageview']);
@@ -22,7 +21,6 @@
     ga.src = ('https:' == document.location.protocol ? 'https://ssl' : 'http://www') + '.google-analytics.com/ga.js';
     var s = document.getElementsByTagName('script')[0]; s.parentNode.insertBefore(ga, s);
   })();
-
 </script>
 <script type="text/javascript">
     (function() {
@@ -72,6 +70,14 @@
                 <form class="well form-inline">
                     <label>Compiler: <select class="compiler"></select></label>
                     <label>Compiler options: <input class="compiler_options" style="width: 30em;" type="text" value="-O2 -std=c++0x -march=native"></label>
+                    <table><tbody><tr><td>Filter:&nbsp;</td>
+                    <td>
+                        <div class="btn-group filter">
+                            <button class="btn" value="labels">Unused labels</button>
+                            <button class="btn" value="directives">Directives</button>
+                            <button class="btn" value="commentOnly">Comment-only lines</button>
+                        </div>
+                    </td></table>
                 </form>
             </div>
        </div>