optimize varargs calls by avoiding calling allocate there

src/jsifier.js

@@ -1063,7 +1063,18 @@ function JSify(data, functionsOnly, givenFunctions) {
         varargs = [0];
         varargsTypes = ['i32'];
       }
-      varargs = makePointer('[' + varargs + ']', 0, 'ALLOC_STACK', varargsTypes);
+      var offset = 0;
+      varargs = '(tempInt=' + RuntimeGenerator.stackAlloc(varargs.length, ',') + ',' +
+                varargs.map(function(arg, i) {
+                  var type = varargsTypes[i];
+                  if (type == 0) return null;
+                  if (I64_MODE == 1 && type == 'i64') type = 'i32'; // We have [i64, 0, 0, 0, i32, 0, 0, 0] in the layout at this point
+                  var ret = makeSetValue(getFastValue('tempInt', '+', offset), 0, arg, type, null, null, QUANTUM_SIZE);
+                  offset += Runtime.getNativeFieldSize(type);
+                  return ret;
+                }).filter(function(arg) {
+                  return arg !== null;
+                }).join(',') + ',tempInt)';
     }
 
     args = args.concat(varargs);

src/runtime.js

@@ -7,24 +7,26 @@
 // itself is as optimized as possible - no unneeded runtime checks).
 
 var RuntimeGenerator = {
-  alloc: function(size, type, init) {
+  alloc: function(size, type, init, sep) {
+    sep = sep || ';';
     var ret = type + 'TOP';
     if (init) {
-      ret += '; _memset(' + type + 'TOP, 0, ' + size + ')';
+      ret += sep + '_memset(' + type + 'TOP, 0, ' + size + ')';
     }
-    ret += '; ' + type + 'TOP += ' + size;
+    ret += sep + type + 'TOP += ' + size;
     if ({{{ QUANTUM_SIZE }}} > 1) {
-      ret += ';' + RuntimeGenerator.alignMemory(type + 'TOP', {{{ QUANTUM_SIZE }}});
+      ret += sep + RuntimeGenerator.alignMemory(type + 'TOP', {{{ QUANTUM_SIZE }}});
     }
     return ret;
   },
 
   // An allocation that lives as long as the current function call
-  stackAlloc: function(size) {
-    if (USE_TYPED_ARRAYS === 2) 'STACKTOP += STACKTOP % ' + ({{{ QUANTUM_SIZE }}} - (isNumber(size) ? Math.min(size, {{{ QUANTUM_SIZE }}}) : {{{ QUANTUM_SIZE }}})) + ';';
-    var ret = RuntimeGenerator.alloc(size, 'STACK', INIT_STACK);
+  stackAlloc: function(size, sep) {
+    sep = sep || ';';
+    if (USE_TYPED_ARRAYS === 2) 'STACKTOP += STACKTOP % ' + ({{{ QUANTUM_SIZE }}} - (isNumber(size) ? Math.min(size, {{{ QUANTUM_SIZE }}}) : {{{ QUANTUM_SIZE }}})) + sep;
+    var ret = RuntimeGenerator.alloc(size, 'STACK', INIT_STACK, sep);
     if (ASSERTIONS) {
-      ret += '; assert(STACKTOP < STACK_ROOT + STACK_MAX, "Ran out of stack")';
+      ret += sep + 'assert(STACKTOP < STACK_ROOT + STACK_MAX, "Ran out of stack")';
     }
     return ret;
   },
@@ -63,7 +65,7 @@ var RuntimeGenerator = {
     if (typeof quantum !== 'number') {
       quantum = '(quantum ? quantum : {{{ QUANTUM_SIZE }}})';
     }
-    return target + ' = ' + Runtime.forceAlign(target, quantum) + ';';
+    return target + ' = ' + Runtime.forceAlign(target, quantum);
   }
 };