# Compilers: How To Make a Programming Language

Other compiler-related topics out of scope:
- What are programs anyway (Forth, LISP)
- Computation: Turing machines, lambda calculus
- Compiler optimization
- GC (motivated by LISP)

aesthetics:
- stay motivated; stick close to a c-like, imperative, procedural model because that's what people are used to

motivation / goals / what questions are we trying to answer:
- I want to be able to make a toy procedural language.
    - like C, Algol, JS, Lua, etc.
    - possible user motivations:
        - I want to make a game scripting language
        - I want to make a DSL for my job (and I want syntax highlighting!)
- I want to do simple static analysis of my projects

ok what do we want to cover
- classical compiler structure (lexer -> parser -> codegen)

| Title                        | Page |
|------------------------------|------|
| Phases of a Compiler         | https://www.geeksforgeeks.org/phases-of-a-compiler/ |
| Compiler Architecture        | https://cs.lmu.edu/~ray/notes/compilerarchitecture/ |
| Compiler Design              | https://www.tutorialspoint.com/compiler_design/compiler_design_phases_of_compiler.htm |
| Structure of a Compiler      | https://www.csd.uwo.ca/~mmorenom/CS447/Lectures/Introduction.html/node10.html |
| The Structure of a Compiler  | https://www.brainkart.com/article/The-Structure-of-a-Compiler_8121/ |
| Wikipedia: Compiler          | https://en.wikipedia.org/wiki/Compiler |
| Compiler Phases              | https://www.javatpoint.com/compiler-phases |
| The Structure of a Compiler  | https://pages.cs.wisc.edu/~fischer/cs536.s08/lectures/Lecture04.4up.pdf |
| Phases of a Compiler         | https://www.guru99.com/compiler-design-phases-of-compiler.html |
| Writing a C Compiler (Pt. 1) | https://norasandler.com/2017/11/29/Write-a-Compiler.html |
| V: Structure of a Compiler   | https://www.youtube.com/watch?v=RH02jcUiPI0 |
| V: Phases of a Compiler      | https://www.youtube.com/watch?v=jE7f3sGLGVk |
| V: Compiler Design           | https://www.youtube.com/watch?v=OZSGjRSHYUk |
| V: Different Phases of Comp  | https://www.youtube.com/watch?v=TApMNhQPaCM |
| V: Phases of Compiler        | https://www.youtube.com/watch?v=r2BRNodqbgI |
| V: Parser and Lexer (Pt. 1)  | https://www.youtube.com/watch?v=eF9qWbuQLuw |

- semantic analysis / type checking
- modern compiler structures (IR / SSA, optimization)
- interpreters vs. JITs vs. AOTs vs. "transpilers"
- executables and linkers
- regular expressions?
- regular languages / grammars / language structure / automata
- terminology?

the c compilation process
- translation units
- preprocessing -> (the whole compilation process) -> object files -> linking
- c compilation model is not in favor any more, don't like compiling all these files separately
- ABIs and FFI
- should maybe be in separate article

experts / consultants:
- Bill
- NeGate

## The actual progression

- Simple expression interpreter (parse and evaluate)
- Classical compiler construction (lex -> parse -> output), semantic analysis / type checking
    - motivation: complex structures! recursion! etc.
    - many of these resources exist and cover different aspects of the process in different ways
- Grammars and language structure
- Types of output (interpreter vs. AOT vs. JIT, etc.)
    - We can probably find resources on specific ones of these
- Modern phases (IR / SSA)
    - Mention WASM?
- The terrors of the real world
    - Executables, linkers, and debug info
    - The C ABI and FFI
    - Register allocation
- C is not the only language
    - LISP
    - Forth
    - This could be a whole topic maybe

## Link dump

### Books

- Engineering a Compiler: 
    [Well liked]
    http://www.r-5.org/files/books/computers/compilers/writing/Keith_Cooper_Linda_Torczon-Engineering_a_Compiler-EN.pdf
- Compiler Design in C:
    [May have a full implementation inside]
    https://holub.com/goodies/compiler/compilerDesignInC.pdf
- Dragon Book: 
    [Potentially outdated -- mixed reviews]
    http://ce.sharif.edu/courses/94-95/1/ce414-2/resources/root/Text%20Books/Compiler%20Design/Alfred%20V.%20Aho,%20Monica%20S.%20Lam,%20Ravi%20Sethi,%20Jeffrey%20D.%20Ullman-Compilers%20-%20Principles,%20Techniques,%20and%20Tools-Pearson_Addison%20Wesley%20(2006).pdf

### Webpages

- lua grammar: http://lua-users.org/wiki/LuaGrammar
- pascal railroad diagrams: https://www.cs.utexas.edu/users/novak/grammar.html
- tons of links: https://github.com/aalhour/awesome-compilers
- expression parsing examples:
    - pratt parsing and recursive descent: https://journal.stuffwithstuff.com/2011/03/19/pratt-parsers-expression-parsing-made-easy/
    - dunno, not recursive descent: https://www.cs.rochester.edu/u/nelson/courses/csc_173/grammars/parsing.html
- gary bernhardt's compiler from scratch: https://www.destroyallsoftware.com/screencasts/catalog/a-compiler-from-scratch
- lambda calculus interpreter: https://justine.lol/lambda/
- chibicc (full, readable C compiler): https://github.com/rui314/chibicc
- A Compiler Writing Journey (has many pages/topics): https://github.com/DoctorWkt/acwj

#### From NeGate
- Near-Optimal Instruction Selection on DAGs: https://llvm.org/pubs/2008-CGO-DagISel.pdf
- The Design and Implementation of Gnu Compiler Generation Framework: https://www.cse.iitb.ac.in/~uday/courses/cs715-10/cs715-gcc-intro-handout.pdf
- Lecture Notes on Static Single Assignment Form: https://www.cs.cmu.edu/~rjsimmon/15411-f15/lec/10-ssa.pdf
- Simple and Efficient Construction of Static Single Assignment Form: https://pp.info.uni-karlsruhe.de/uploads/publikationen/braun13cc.pdf
- LLVM Greedy Register Allocator – Improving Region Split Decisions: https://llvm.org/devmtg/2018-04/slides/Yatsina-LLVM%20Greedy%20Register%20Allocator.pdf
- NULLSTONE Optimization Categories: ttp://www.nullstone.com/htmls/category.htm