Import SIMD feature and add some workload samples (#438)

samples/workload/README.md

@@ -0,0 +1,34 @@
+All workloads have similar a requirment of software dependencies. It includes
+**wasi-sdk**, **clang-11**, **emsdk**, **wabt** and **binaryen**
+
+> It might slightly different when using MacOS, and other linux distro than Ubuntu. This document only target
+Ubuntu 18.04 as an example.
+
+## Installation instructions
+
+- **wasi-sdk**. Install
+  [latest release](https://github.com/WebAssembly/wasi-sdk/releases/download/wasi-sdk-11/wasi-sdk-11.0-linux.tar.gz)
+  in */opt/wasi-sdk* or */opt/wasi-sdk-11*
+
+- **wabt**. Install
+  [latest release](https://github.com/WebAssembly/wabt/releases/download/${WABT_VER}/wabt-1.0.19-ubuntu.tar.gz)
+  in */opt/wabt* or */opt/wabt-1.0.19*
+
+- **clang-11**. Refer to [the guide](https://apt.llvm.org/).
+
+- **emsdk**. Refer to [the guide](https://emscripten.org/docs/getting_started/downloads.html). Don't forget to activate
+  emsdk and set up environment variables. Verify it with `echo ${EMSDK}`.
+
+- **libclang_rt.builtins-wasm32.a**. *wasi* has its private rt library. Put it under clang search path
+
+``` shell
+# copy it
+$ cp -r /opt/wasi-sdk-11.0/lib/clang/10.0.0/lib/wasi /usr/lib/llvm-11/lib/clang/11.0.0/lib/
+
+# or just link it
+$ ln -sf /opt/wasi-sdk-11.0/lib/clang/10.0.0/lib/wasi/ /usr/lib/llvm-11/lib/clang/11.0.0/lib/
+```
+
+- **binaryen**. Install
+  [latest release](https://github.com/WebAssembly/binaryen/releases/download/version_97/binaryen-version_97-x86_64-linux.tar.gz)
+  in */opt/binaryen* or */opt/binaryen-version_97*