Parser fixes; Lib updates

lib/utils/index.js

@@ -1,21 +1,103 @@
-module.exports = function(module) {
-  return {
-    getI32: function(ptr) {
-      return new Int32Array(module.memory.buffer, ptr, 4)[0];
-    },
-    getU32: function(ptr) {
-      return new Uint32Array(module.memory.buffer, ptr, 4)[0];
-    },
-    getF32: function(ptr) {
-      return new Float32Array(module.memory.buffer, ptr, 4)[0];
-    },
-    getF64: function(ptr) {
-      return new Float64Array(module.memory.buffer, ptr, 8)[0];
-    },
-    getString: function(ptr) {
-      var len = new Uint32Array(module.memory.buffer, ptr, 4)[0];
-      var str = new Uint16Array(module.memory.buffer, ptr + 4, len << 1);
-      return String.fromCharCode.apply(String, str);
-    }
+function utils(module) {
+
+  var i8,
+      u8 = new Uint8Array(0),
+      i16,
+      u16,
+      i32,
+      u32,
+      f32,
+      f64;
+
+  function maybeUpdate() {
+    var mem = module.memory.buffer;
+    if (mem.byteLength === u8.length)
+      return;
+    i8 = Int8Array(mem);
+    u8 = Uint8Array(mem);
+    i16 = Int16Array(mem);
+    u16 = Uint16Array(mem);
+    i32 = Int32Array(mem);
+    u32 = Uint32Array(mem);
+    f32 = Float32Array(mem);
+    f64 = Float64Array(mem);
   }
+
+  var helpers = {
+
+    i8: function(ptr) {
+      maybeUpdate();
+      return i8[ptr];
+    },
+
+    u8: function(ptr) {
+      maybeUpdate();
+      return u8[ptr];
+    },
+
+    i16: function(ptr) {
+      maybeUpdate();
+      return i16[ptr >>> 1];
+    },
+
+    u16: function(ptr) {
+      maybeUpdate();
+      return u16[ptr >>> 1];
+    },
+
+    i32: function(ptr) {
+      maybeUpdate();
+      return i32[ptr >>> 2];
+    },
+
+    u32: function(ptr) {
+      maybeUpdate();
+      return u32[ptr >>> 2];
+    },
+
+    i64: function(ptr) {
+      maybeUpdate();
+      return {
+        low: i32[ptr >>> 2],
+        high: i32[(ptr >>> 2) + 1]
+      };
+    },
+
+    u64: function(ptr) {
+      maybeUpdate();
+      return {
+        low: u32[ptr >>> 2],
+        high: u32[(ptr >>> 2) + 1]
+      };
+    },
+
+    bool: function(ptr) {
+      maybeUpdate();
+      return u8[ptr] === 1;
+    },
+
+    f32: function(ptr) {
+      maybeUpdate();
+      return f32[ptr >>> 2];
+    },
+
+    f64: function(ptr) {
+      maybeUpdate();
+      return f64[ptr >>> 3];
+    },
+
+    string: function(ptr) {
+      maybeUpdate();
+      var len = u32[ptr >>> 2];
+      var off = (ptr >>> 1) + 2;
+      return String.fromCharCode.apply(String, u16.subarray(off, off + len));
+    }
+  };
+
+  return helpers;
 };
+
+Object.defineProperties(module.exports = utils, {
+  __esModule: { value: true },
+  default: { value: utils }
+});