Hawk is a Just-In-Time (JIT) compiler for the Scheme programming language.
Hawk is Copyright (C) 2023 Dave Watson. Hawk is free software, released under the MIT license. See full Copyright Notice in the LICENSE file.
See the doc/ folder for additional documentation.
hawk [options] file.[scm|bc] ...
https://djwatson.github.io/hawk
hawk is a vm (virtual machine) and jit compiler (just-in-time) for the scheme
language, report version r5rs. It can run scripts directly, or pre-compile them
to an executable.
--joff
Turn off the jit compiler, only use the bytecode VM.
-m, --max-trace NUMBER
Only trace up to NUMBER traces, and then only interpret.
--dump
Turn on debugging dumps for gdb and linux perf tool.
-l, --list
Compile the script and dump the resulting code in human-readable
format to stdout, and then quit.
-p, --profile
Turn on the bytecode profiler. After the script finishes,
statistics gathered are printed to stdout.
--exe
Compile the script in to an exe by linking it with libhawk_exe.
Note that this is no faster than running a .bc file directly
with hawk, and is only a convenience. Script is only compiled
and not run.
-s, --heap-sz
Set the maximum heap size, in pages (4096 bytes). Default is 12000 pages.
-v, --verbose
Turn on verbosity. Prints tracing info, generated trace IR, and
machine code. Also displays GC collection info.
-h, --help
Print help message and exit.
./hawk hello.scm
Prints 'hello world', assuming hello.scm contains
(display "hello world")
Compile the hello.scm script to an executable:
./hawk --exe hello.scm ./hello
Currently hawk is closest to the r4rs standard, with the following restrictions:
- Symbols starting with '$' are reserved
- Bignums / complex / ratios are unimplemented, only fixnum overflowing to flownum are supported.
- syntax-rules cannot be defined in one file, and used in another.
- Modules are not implemented, including the builtin library: While you can redefine most builtin procedures (assuming integration is turned off), many library functions still call these procedures through the global table. E.g. if you redefine 'car', 'caar' will call the new procedure twice.
- The lexer is r7rs compliant.
- No unicode, all strings are ascii-only.
- Bytevectors are just defined to be strings.
And jit restrictinos:
- x86_64 / sysv only. Known to work on linux & osx intel.
- flonums are unimplemented in the jit.
- Most file operations fallback to VM.