minigo

README

minigo🐥

A Go compiler made from scratch.

Notice

This repository is no longer maintained actively.

I made another Go compiler babygo from scratch again, which is much more simple, sophisticated and understandable.

Please look at https://github.com/DQNEO/babygo

Description

minigo🐥 is a small Go compiler made from scratch. It can compile itself.

• Generates a single static binary executable
• No dependency on yacc/lex or any external libraries
• Standard libraries are also made from scratch

It depends only on GNU Assembler and GNU ld.

minigo supports x86-64 Linux only.

Design

I made this almost without reading the original Go compiler.

minigo inherits most of its design from the following:

• 8cc (https://github.com/rui314/8cc)
• 8cc.go (https://github.com/DQNEO/8cc.go)

There are several steps in the compilation process.

[go source] -> byte_stream.go -> [byte stream] -> token.go -> [token stream] -> parser.go -> [AST] -> gen.go -> [assembly code]

How to run

You need Linux, so I would recommend that you use Docker.

$ docker run --rm -it -w /mnt -v `pwd`:/mnt dqneo/ubuntu-build-essential:go bash

After entering the container, you can build and run it.

$ make
$ ./minigo t/hello/hello.go > hello.s
$ as -o hello.o hello.s
$ ld -o hello hello.o
$ ./hello
hello world

How to "self compile"

$ make
$ ./minigo --version
minigo 0.1.0
Copyright (C) 2019 @DQNEO

$ ./minigo *.go > /tmp/minigo2.s
$ as -o /tmp/minigo2.o /tmp/minigo2.s
$ ld -o minigo2 /tmp/minigo2.o
$ ./minigo2 --version
minigo 0.1.0
Copyright (C) 2019 @DQNEO

$ ./minigo2 *.go > /tmp/minigo3.s
$ as -o /tmp/minigo3.o /tmp/minigo3.s
$ ld -o minigo3 /tmp/minigo3.o
$ ./minigo3 --version
minigo 0.1.0
Copyright (C) 2019 @DQNEO

You will see that the contents of 2nd generation compiler and 3rd generation compiler are identical.

$ diff /tmp/minigo2.s /tmp/minigo3.s

Test

$ make test

Debug by gdb

Add --cap-add=SYS_PTRACE --security-opt='seccomp=unconfined' option to docker run. It will allow you to use gdb in the docker image.

docker run --cap-add=SYS_PTRACE --security-opt='seccomp=unconfined' -it --rm -w /mnt -v `pwd`:/mnt --tmpfs=/tmp/tmpfs:rw,size=500m,mode=1777 dqneo/ubuntu-build-essential:go bash

The Assembly language

We are currently using GNU assembler in AT&T syntax.

https://sourceware.org/binutils/docs/as/i386_002dDependent.html#i386_002dDependent

AUTHOR

@DQNEO

LICENSE

MIT License

Documentation

Overview

builder builds packages

gen_load handles loading of expressions

Semantic Analyzer to produce IR struct