Add benchmarks (#979)

Add scripts to build and run benchmark of coremark, polybench,
sightglass and jetstream2. And add documents.

tests/benchmarks/coremark/README.md

@@ -0,0 +1,19 @@
+# Introduction
+
+[CoreMark's](https://www.eembc.org/coremark) primary goals are simplicity and providing a method for testing only a processor's core features.
+
+**Source**: https://github.com/eembc/coremark
+
+# Building
+
+Please build iwasm and wamrc, refer to:
+- [Build iwasm on Linux](../../../doc/build_wamr.md#linux), or [Build iwasm on MacOS](../../../doc/build_wamr.md#macos)
+- [build wamrc AOT compiler](../../../README.md#build-wamrc-aot-compiler)
+
+And install WASI SDK, please download the [wasi-sdk release](https://github.com/CraneStation/wasi-sdk/releases) and extract the archive to default path `/opt/wasi-sdk`.
+
+And then run `./build.sh` to build the source code, file `coremark.exe`, `coremark.wasm` and `coremark.aot` will be generated.
+
+# Running
+
+Run `./run.sh` to test the benchmark, the native mode, iwasm aot mode and iwasm interpreter mode will be tested respectively.

tests/benchmarks/coremark/build.sh

@@ -0,0 +1,35 @@
+#!/bin/bash
+
+# Copyright (C) 2019 Intel Corporation.  All rights reserved.
+# SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+
+WAMRC="../../../wamr-compiler/build/wamrc"
+
+if [ ! -d coremark ]; then
+    git clone https://github.com/eembc/coremark.git
+fi
+
+cd coremark
+
+echo "Build coremark with gcc .."
+gcc -O3 -Iposix -I. -DFLAGS_STR=\""-O3 -DPERFORMANCE_RUN=1  -lrt"\" \
+        -DITERATIONS=0 -DPERFORMANCE_RUN=1 \
+        core_list_join.c core_main.c core_matrix.c core_state.c \
+        core_util.c posix/core_portme.c \
+        -o ../coremark.exe -lrt
+
+echo "Build coremark with wasi-sdk .."
+/opt/wasi-sdk/bin/clang -O3 -Iposix -I. -DFLAGS_STR=\""-O3 -DPERFORMANCE_RUN=1"\" \
+        -Wl,--export=main \
+        -DITERATIONS=0 -DPERFORMANCE_RUN=1 \
+        -Wl,--allow-undefined \
+        core_list_join.c core_main.c core_matrix.c core_state.c \
+        core_util.c posix/core_portme.c \
+        -o ../coremark.wasm
+
+cd ..
+
+echo "Compile coremark.wasm to coremark.aot .."
+${WAMRC} -o coremark.aot coremark.wasm
+
+echo "Done"

tests/benchmarks/coremark/run.sh

@@ -0,0 +1,16 @@
+#!/bin/bash
+
+# Copyright (C) 2019 Intel Corporation.  All rights reserved.
+# SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+
+IWASM="../../../product-mini/platforms/linux/build/iwasm"
+WAMRC="../../../wamr-compiler/build/wamrc"
+
+echo "Run coremark with native .."
+./coremark.exe
+
+echo "Run coremark with iwasm mode .."
+${IWASM} coremark.aot
+
+echo "Run coremakr with iwasm interpreter .."
+${IWASM} coremark.wasm