1 files changed, 10 insertions, 3 deletions
diff --git a/src/parseTools.js b/src/parseTools.js
index 7d1a7cd9..6e0d6e32 100644
--- a/src/parseTools.js
+++ b/src/parseTools.js
@@ -103,6 +103,11 @@ function isNiceIdent(ident, loose) {
   }
 }
 
+function isJSVar(ident) {
+  return /^\(?[$_]?[\w$_\d ]*\)+$/.test(ident);
+
+}
+
 function isStructPointerType(type) {
   // This test is necessary for clang - in llvm-gcc, we
   // could check for %struct. The downside is that %1 can
@@ -988,7 +993,8 @@ function getHeapOffset(offset, type, forceAsm) {
     if (shifts != 0) {
       return '(' + offset + '>>' + shifts + ')';
     } else {
-      return offset;
+      // we need to guard against overflows here, HEAP[U]8 expects a guaranteed int
+      return isJSVar(offset) ? offset : '(' + offset + '|0)';
     }
   }
 }
@@ -1393,7 +1399,8 @@ function getFastValue(a, op, b, type) {
       if (!(type in Runtime.FLOAT_TYPES)) {
         // if guaranteed small enough to not overflow into a double, do a normal multiply
         var bits = getBits(type) || 32; // default is 32-bit multiply for things like getelementptr indexes
-        if ((isNumber(a) && Math.abs(a) < TWO_TWENTY) || (isNumber(b) && Math.abs(b) < TWO_TWENTY) || bits < 32) {
+        // Note that we can emit simple multiple in non-asm.js mode, but asm.js will not parse "16-bit" multiple, so must do imul there
+        if ((isNumber(a) && Math.abs(a) < TWO_TWENTY) || (isNumber(b) && Math.abs(b) < TWO_TWENTY) || (bits < 32 && !ASM_JS)) {
           return '(((' + a + ')*(' + b + '))&' + ((Math.pow(2, bits)-1)|0) + ')'; // keep a non-eliminatable coercion directly on this
         }
         return 'Math.imul(' + a + ',' + b + ')';
@@ -1541,7 +1548,7 @@ function makePointer(slab, pos, allocator, type, ptr) {
     var ret = '';
     var index = 0;
     while (index < array.length) {
-      ret = (ret ? ret + '.concat(' : '') + '[' + array.slice(index, index + chunkSize).map(JSON.stringify) + ']' + (ret ? ')' : '');
+      ret = (ret ? ret + '.concat(' : '') + '[' + array.slice(index, index + chunkSize).map(JSON.stringify) + ']' + (ret ? ')\n' : '');
       index += chunkSize;
     }
     return ret;