Update sample workload wasm-av1 and add workload XNNPACK (#443)

samples/workload/wasm-av1/README.md

@@ -1,22 +1,56 @@
 "wasm-av1" sample introduction
 ==============
-This sample demonstrates how to build [wasm-av1](https://github.com/GoogleChromeLabs/wasm-av1) into WebAssembly with emcc toolchain and run it with iwasm. Please first install [emsdk](https://github.com/emscripten-core/emsdk):
-```bash
-git clone https://github.com/emscripten-core/emsdk.git
-cd emsdk
-./emsdk install latest
-./emsdk activate latest
-```
-And set up ensdk environment:
-```bash
-source emsdk_env.sh
-```
-Then run
+
+This sample demonstrates how to build [wasm-av1](https://github.com/GoogleChromeLabs/wasm-av1) into
+WebAssembly with simd support and run it with iwasm.
+
+## Preparation
+
+please refer to [installation instructions](../README.md).
+
+## Build with EMSDK
+
+just run the convenience script:
+
 ```bash
 ./build.sh
 ```
-to build wasm-av1 and run it with iwasm, which basically contains the following steps:
+
+it is going to build wasm-av1 and run it with iwasm, which basically contains the following steps:
 - hack emcc to delete some objects in libc.a
 - patch wasm-av1 and build it with emcc compiler
 - build iwasm with simd and libc-emcc support
 - run testav1.aot with iwasm
+
+## Or build with clang-11 and wasi-sdk
+
+``` shell
+$ mkdir build && cd build
+$ cmake ..
+$ make
+# to verify
+$ ls testavx.wasm
+```
+
+### Run workload
+
+Firstly please build iwasm with simd support:
+
+``` shell
+$ cd <wamr dir>/product-mini/platforms/linux/
+$ mkdir build && cd build
+$ cmake .. -DWAMR_BUILD_SIMD=1
+$ make
+```
+
+Then compile wasm file to aot file and run:
+
+``` shell
+$ cd <wamr dir>/wamr-compiler/build
+$ ./wamrc --enable-simd -o testavx.aot testavx.wasm
+$ cd <wamr dir>/product-mini/platforms/linux/
+$ # copy sample data like <wamr dir>/samples/workload/wasm-av1/av1/third_party/samples/elephants_dream_480p24.ivf
+$ # copy testavx.aot
+$ # make sure you declare the access priority of the directory in which the sample data is
+$ ./iwasm --dir=. ./testavx.aot ./elephants_dream_480p24.ivf
+```