Added readme

Author: Conarnar

CMakeLists.txt

@@ -746,7 +746,7 @@ endif()
 if(EXECUTORCH_BUILD_WASM)
   add_subdirectory(${CMAKE_CURRENT_SOURCE_DIR}/extension/wasm)
   if(EXECUTORCH_BUILD_WASM_DEMO)
-    add_subdirectory(${CMAKE_CURRENT_SOURCE_DIR}/examples/wasm)
+    add_subdirectory(${CMAKE_CURRENT_SOURCE_DIR}/examples/wasm/demo)
   endif()
 endif()
 

examples/wasm/CMakeLists.txt renamed to examples/wasm/demo/CMakeLists.txt

@@ -0,0 +1,30 @@
+# ExecuTorch JavaScript Bindings Demo
+
+This demo showcases the capabilities of ExecuTorch's JavaScript bindings. It is able to load a model, run inference, and classify an image natively in the browser.
+
+## Prerequisites
+
+- [Emscripten](https://emscripten.org/docs/getting_started/Tutorial.html)
+
+## Building and Running
+
+To build the demo, run the following command from the root of the repository:
+
+```
+cd executorch # To the top level dir
+
+# Build the demo
+bash scripts/build_wasm_demo.sh
+
+# Run the demo
+python3 -m http.server --directory cmake-out-wasm/examples/wasm/demo/
+```
+
+The page will be available at http://localhost:8000/demo.html.
+
+## Demo Features
+
+- Load a model from a file
+  - It currently only supports the MobileNetv2 model. Passing in a model with different input/output shapes will result in an error.
+  - You can generate the model file by following the instructions in the [Portable Mode Readme](../../portable/README.md).
+- Run inference on an image