gistfile1.txt

diff --git a/js/src/builtin/ParallelArray.js b/js/src/builtin/ParallelArray.js
index da5402e..fdec070 100644
--- a/js/src/builtin/ParallelArray.js
+++ b/js/src/builtin/ParallelArray.js
@@ -1399,13 +1399,14 @@ function ParallelMatrixConstructFromGrainFunctionMode(arg0, arg1, arg2, arg3) {
   case 1:
     computefunc = isLeaf ? fill1_leaf : fill1_subm;
     break;
-
+/*
   case 2:
     computefunc = isLeaf ? fill2_leaf : fill2_subm;
     break;
   case 3:
     computefunc = isLeaf ? fill3_leaf : fill3_subm;
     break;
+*/
 
   default:
     computefunc = isLeaf ? fillN_leaf : fillN_subm;
@@ -1543,8 +1544,16 @@ function ParallelMatrixConstructFromGrainFunctionMode(arg0, arg1, arg2, arg3) {
   function fillN_leaf(indexStart, indexEnd) {
     var frame_indices = ComputeIndices(frame, indexStart);
     for (i = indexStart; i < indexEnd; i++) {
+      var used_outptr = false;
+      function set(v) { UnsafeSetElement(buffer, i, val); used_outptr = true; }
+      var outptr = {};
+      outptr.set = set;
+      frame_indices.push(outptr);
       var val = func.apply(null, frame_indices);
-      UnsafeSetElement(buffer, i, val);
+      if (!used_outptr) {
+        UnsafeSetElement(buffer, i, val);
+      }
+      frame_indices.pop();
       StepIndices(frame, frame_indices);
     }
   }
@@ -1557,10 +1566,37 @@ function ParallelMatrixConstructFromGrainFunctionMode(arg0, arg1, arg2, arg3) {
 
     // FIXME: Something seems off about handling of i, indexStart, bufoffset...
     for (i = indexStart; i < indexEnd; i++, bufoffset += grainLen) {
+      var used_outptr = false;
+
+      function set() {
+        var v = arguments.pop();
+        var offset = 0;
+        if (arguments.length > grain.length) {
+          ThrowError(JSMSG_PAR_ARRAY_BAD_ARG, ": too many args to outptr.set");
+        }
+        if (arguments.length < grain.length) {
+          ThrowError(JSMSG_PAR_ARRAY_BAD_ARG, ": outptr.set curry not yet unsupported");
+        }
+        for (var i = 0; i < grain.length; i++) {
+          var arg_i = arguments[i];
+          if (arg_i >= grain[i]) {
+            ThrowError(JSMSG_PAR_ARRAY_BAD_ARG, ": outptr.set index too large");
+          }
+          offset += arg_i * arguments.slice(i+1).reduce((a,b) => a*b);
+        }
+        UnsafeSetElement(buffer, bufoffset + offset, v);
+        used_outptr = true;
+      }
+      var outptr = {};
+      outptr.set = set;
+      frame_indices.push(outptr);
       var subarray = func.apply(null, frame_indices);
+      frame_indices.pop();
       var [subbuffer, suboffset] =
         IdentifySubbufferAndSuboffset(subarray);
-      CopyFromSubbuffer(buffer, bufoffset, subbuffer, suboffset);
+      if (!used_outptr) {
+        CopyFromSubbuffer(buffer, bufoffset, subbuffer, suboffset);
+      }
       StepIndices(frame, frame_indices);
     }
   }