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pre { line-height: 125%; }
td.linenos .normal { color: inherit; background-color: transparent; padding-left: 5px
This tool is 2 things:

a) An emulator for SubX, the subset of the 32-bit x86 instruction set used by
Mu.

b) A second translator for SubX programs that emits identical binaries to the
self-hosting versions in the parent directory. Having two diverse compilers
(one in a familiar language, one with minimal syscall surface area) that emit
identical binaries should help gain confidence in Mu.

## Running

`bootstrap` currently has the following sub-commands:

- `bootstrap help`: some helpful documentation to have at your fingertips.

- `bootstrap test`: runs all automated tests.

- `bootstrap translate <input files> -o <output ELF binary>`: translates `.subx`
  files into an executable ELF binary.

- `bootstrap run <ELF binary> <args>`: simulates running the ELF binaries emitted
  by `bootstrap translate`. Useful for testing and debugging.

  Remember, not all 32-bit Linux binaries are guaranteed to run. I'm not
  building general infrastructure here for all of the x86 instruction set.
  SubX is about programming with a small, regular subset of 32-bit x86.

## Hacking

This directory is the only C++ code in the project, and has [an unconventional
organization](http://akkartik.name/post/four-repos).
generated by cgit-pink 1.4.1-2-gfad0 (git 2.36.2.497.gbbea4dcf42) at 2024-10-19 09:44:32 +0000
))) (defclass <lsymbol> (<lexeme>) ((lsymbol :reader lsymbol))) (defclass <lstring> (<lexeme>) ((lstring :reader lstring))) (defclass <lend> (<lexeme>) ()) (defclass <string-lexer> () ((string :initarg s :accessor string) (current :initform 0 :accessor current) (size :accessor size))) (defmethod initialize-object :after ((self <string-lexer>) initargs) (setf (size self) (length (str self)))) (defgeneric forward (cl &rest args)) (defmethod forward ((cl <string-lexer>) &rest args) (let ((incr (if (null args) 1 (car args)))) (setf (curr cl) (+ (curr cl) incr)))) (defgeneric extract (pred cl)) (defmethod extract (pred (cl <string-lexer>)) (let* ((st (string cl)) (pos (current cl)) (ext (lambda (n) (if (and (< n (size cl)) (pred (elt st n))) (ext (+ n 1)) n))) (res (ext pos))) (setf (current cl) res) (subseq (string cl) pos (- res pos)))) (defgeneric extract-int (cl)) (defmethod extract-int ((cl <string-lexer>)) (flet ((is-int (x) (and (char>= x #\0) (char<= x #\9)))) (convert (extract is-int cl) <number>))) (defgeneric extract-ident (cl)) (defmethod extract-ident ((cl <string-lexer>)) (flet ((is-alpha-num (x) (or (and (char>= x #\a) (char<= x #\z)) (and (char>= x #\A) (char<= x #\Z)) (and (char>= x #\0) (char<= x #\9)) (char= x #\_)))) (extract is-alpha-num))) (provide "lex")