---
tags: CSIE
---
# GEM5小教室
## How to run gem5
### 0.Download gem5
- 我們會利用git來下載gem5，所以要先準備好[git](https://git-scm.com/)
`sudo apt install git`

- 之後直接從官網的教學範例下載gem5
`git clone https://gem5.googlesource.com/public/gem5`

### 1.Build gem5

/usr/bin/env python3 /usr/bin/scons build/X86/gem5.opt -j 8

>使用的環境是python3
>X86是指這次模擬的ISA
>`-j 4`是指用4個thread去跑
### 2.Run Hello World

build/X86/gem5.opt configs/example/se.py --cmd=tests/test-progs/hello/bin/x86/linux/hello

>在gem5的資料夾直接
>上面單純就是讓它跑，下面則是有使用到cache
>se : System call emulation mode

build/X86/gem5.opt configs/example/se.py --cmd=tests/test-progs/hello/bin/x86/linux/hello --cpu-type=TimingSimpleCPU --l1d_size=64kB --l1i_size=16kB --caches

### 3.Statistics and Output
- 在`gem5/build/x86/m5out`
>我們在範例是使用x86，但還有ARM、RISCV、MIPS...

`config.ini`: 我們設定的系統資訊
`stats.txt`: 模擬出來的output

## run Mibench jpeg encoder/decoder

### 1.先下載Mibench的github

git clone https://github.com/embecosm/mibench.git

>我們gem5與mibench的資料夾各別都放在家目錄下
### 2. Make mibench

到`/mibench/consumer/jpeg/jpeg-6a/`裡去打`make`

cd ~/mibench/consumer/jpeg/jpeg-6a/
make

### 3.Run
先回到gem5的資料夾

cd ~/gem5/

#### small jpeg encoder

build/X86/gem5.opt configs/example/se.py --cmd=../mibench/consumer/jpeg/jpeg-6a/cjpeg --options="-dct int -progressive -opt -outfile output_small_encode.jpeg" --input=../mibench/consumer/jpeg/input_small.ppm

#### small jpeg decoder

build/X86/gem5.opt configs/example/se.py --cmd=../mibench/consumer/jpeg/jpeg-6a/djpeg --options="-dct int -ppm -outfile output_small_decode.ppm" --input=../mibench/consumer/jpeg/input_small.jpg

#### large jpeg encoder

build/X86/gem5.opt configs/example/se.py --cmd=../mibench/consumer/jpeg/jpeg-6a/cjpeg --options="-dct int -progressive -opt -outfile output_large_encode.jpeg ../mibench/consumer/jpeg/input_large.ppm"

#### large jpeg decoder

build/X86/gem5.opt configs/example/se.py --cmd=../mibench/consumer/jpeg/jpeg-6a/djpeg --options="-dct int -ppm -outfile output_large_decode.ppm ../mibench/consumer/jpeg/input_large.jpg"