refactors async

Author: MichealReed

cmake/templates/index.html.in

@@ -12,7 +12,7 @@
       if (typeof Module !== 'undefined') {
         Module.onRuntimeInitialized = function() {
           // Optionally, pass arguments to main in an array.
-          Module._main([]);
+          Module.ccall('main', 'number', [], [], { async: true });
         };
       } else {
         console.error('Module is undefined. Check that your generated JS file is loaded properly.');

examples/hello_world/run.cpp

@@ -38,12 +38,14 @@ int main(int argc, char **argv) {
   Tensor output = createTensor(ctx, Shape{N}, kf32);
   std::promise<void> promise;
   std::future<void> future = promise.get_future();
-  Kernel op = createKernel(ctx, {kGelu, 256, kf32},
+  std::future<Kernel> kernelFuture = createKernel(ctx, {kGelu, 256, kf32},
                            Bindings{input, output},
                            {cdiv(N, 256), 1, 1});
-  dispatchKernel(ctx, op, promise);
-  wait(ctx, future);
-  toCPU(ctx, output, outputArr.data(), sizeof(outputArr));
+  Kernel op = waitForFuture(ctx.instance, kernelFuture);
+  std::future<void> dispatchFuture = dispatchKernel(ctx, op);
+  waitForFuture(ctx.instance, dispatchFuture);
+  std::future<void> cpuFuture = toCPU(ctx, output, outputArr.data(), sizeof(outputArr));
+  waitForFuture(ctx.instance, cpuFuture);
   for (int i = 0; i < 12; ++i) {
     printf("  gelu(%.2f) = %.2f\n", inputArr[i], outputArr[i]);
   }