In this Github repository, I'm documenting my journey to write a self-compiling compiler for a subset of the C language. I'm also writing out the details so that, if you want to follow along, there will be an explanation of what I did, why, and with some references back to the theory of compilers.
But not too much theory, I want this to be a practical journey.
Here are the steps I've taken so far:
- Part 0: Introduction to the Journey
- Part 1: Introduction to Lexical Scanning
- Part 2: Introduction to Parsing
- Part 3: Operator Precedence
- Part 4: An Actual Compiler
- Part 5: Statements
- Part 6: Variables
- Part 7: Comparison Operators
- Part 8: If Statements
- Part 9: While Loops
- Part 10: For Loops
- Part 11: Functions, part 1
- Part 12: Types, part 1
- Part 13: Functions, part 2
- Part 14: Generating ARM Assembly Code
- Part 15: Pointers, part 1
- Part 16: Declaring Global Variables Properly
- Part 17: Better Type Checking and Pointer Offsets
- Part 18: Lvalues and Rvalues Revisited
- Part 19: Arrays, part 1
- Part 20: Character and String Literals
- Part 21: More Operators
- Part 22: Design Ideas for Local Variables and Function Calls
- Part 23: Local Variables
- Part 24: Function Parameters
- Part 25: Function Calls and Arguments
- Part 26: Function Prototypes
- Part 27: Regression Testing and a Nice Surprise
- Part 28: Adding More Run-time Flags
- Part 29: A Bit of Refactoring
- Part 30: Designing Structs, Unions and Enums
- Part 31: Implementing Structs, Part 1
- Part 32: Accessing Members in a Struct
- Part 33: Implementing Unions and Member Access
- Part 34: Enums and Typedefs
- Part 35: The C Pre-Processor
- Part 36:
breakandcontinue - Part 37: Switch Statements
- Part 38: Dangling Else and More
- Part 39: Variable Initialisation, part 1
- Part 40: Global Variable Initialisation
- Part 41: Local Variable Initialisation
- Part 42: Type Casting and NULL
- Part 43: Bugfixes and More Operators
- Part 44: Constant Folding
- Part 45: Global Variable Declarations, revisited
- Part 46: Void Function Parameters and Scanning Changes
- Part 47: A Subset of
sizeof - Part 48: A Subset of
static - Part 49: The Ternary Operator
- Part 50: Mopping Up, part 1
- Part 51: Arrays, part 2
- Part 52: Pointers, part 2
- Part 53: Mopping Up, part 2
- Part 54: Spilling Registers
- Part 55: Lazy Evaluation
- Part 56: Local Arrays
- Part 57: Mopping Up, part 3
- Part 58: Fixing Pointer Increments/Decrements
- Part 59: Why Doesn't It Work, part 1
- Part 60: Passing the Triple Test
- Part 61: What's Next?
- Part 62: Code Cleanup
- Part 63: A New Backend using QBE
- Part 64: A Backend for the 6809 CPU
There isn't a schedule or timeline for the future parts, so just keep checking back here to see if I've written any more.
I have borrowed some of the code, and lots of ideas, from the SubC compiler written by Nils M Holm. His code is in the public domain. I think that my code is substantially different enough that I can apply a different license to my code.
Unless otherwise noted,
- all source code and scripts are (c) Warren Toomey under the GPL3 license.
- all non-source code documents (e.g. English documents, image files) are (c) Warren Toomey under the Creative Commons BY-NC-SA 4.0 license.