Extract portable AS to its own definition and polyfill; Try running flatten/ssa before default optimizations, see WebAssembly/binaryen#1331

src/glue/js.js

@@ -0,0 +1,42 @@
+require("../../portable-assembly");
+
+var globalScope = typeof window !== "undefined" && window || typeof global !== "undefined" && global || self;
+
+var binaryen;
+try {
+  binaryen = require("binaryen");
+} catch (e) {
+  binaryen = globalScope["Binaryen"];
+}
+for (var key in binaryen)
+  if (/^_(?:Binaryen|Relooper|malloc$|free$)/.test(key))
+    globalScope[key] = binaryen[key];
+
+globalScope["store"] = function store(ptr, val) {
+  binaryen.HEAPU8[ptr] = val;
+};
+
+globalScope["load"] = function load_u8(ptr) {
+  return binaryen.HEAPU8[ptr];
+};
+
+var Module = require("../module").Module;
+
+Module.prototype.toBinary = function toBinary(bufferSize) {
+  if (!bufferSize) bufferSize = 1024 * 1024;
+  var ptr = _malloc(bufferSize);
+  var len = this.write(ptr, bufferSize);
+  var ret = new Uint8Array(len);
+  ret.set(binaryen.HEAPU8.subarray(ptr, ptr + len));
+  _free(ptr);
+  return ret;
+}
+
+Module.prototype.toText = function toText() {
+  var previousPrint = binaryen.print;
+  var ret = "";
+  binaryen.print = function print(x) { ret += x + "\n" };
+  this.print();
+  binaryen.print = previousPrint;
+  return ret;
+}