📜 Add better documentation across the compiler. (#3)

These changes pay particular attention to API endpoints, to try to
ensure that any rustdocs generated are detailed and sensible. A good
next step, eventually, might be to include doctest examples, as well.
For the moment, it's not clear that they would provide a lot of value,
though.

In addition, this does a couple refactors to simplify the code base in
ways that make things clearer or, at least, briefer.
This commit is contained in:
2023-05-13 14:34:48 -05:00
parent f4594bf2cc
commit 1fbfd0c2d2
28 changed files with 1550 additions and 432 deletions

View File

@@ -1,17 +1,7 @@
use clap::Parser;
use codespan_reporting::diagnostic::Diagnostic;
use codespan_reporting::files::SimpleFiles;
use codespan_reporting::term;
use codespan_reporting::term::termcolor::{ColorChoice, StandardStream};
use cranelift_object::object;
use ngr::backend::Backend;
use ngr::backend::BackendError;
use ngr::ir::Program as IR;
use ngr::syntax::{ParserError, Program as Syntax};
use target_lexicon::Triple;
use thiserror::Error;
/// Clap is great! Even though we don't have many command line arguments
/// yet, this is just really neat.
#[derive(Parser, Debug)]
#[clap(author, version, about, long_about = None)]
struct CommandLineArguments {
@@ -23,76 +13,14 @@ struct CommandLineArguments {
file: String,
}
#[derive(Debug, Error)]
enum MainError {
#[error(transparent)]
Backend(#[from] BackendError),
#[error("Parser error")]
ParserError(#[from] ParserError),
#[error("IO error")]
IoError(#[from] std::io::Error),
#[error("write error")]
WriteError(#[from] object::write::Error),
}
impl From<MainError> for Diagnostic<usize> {
fn from(value: MainError) -> Self {
match value {
MainError::Backend(be) => be.into(),
MainError::ParserError(pe) => (&pe).into(),
MainError::IoError(e) => Diagnostic::error().with_message(format!("IO error: {}", e)),
MainError::WriteError(e) => {
Diagnostic::error().with_message(format!("Module write error: {}", e))
}
}
}
}
fn compile(file_database: &mut SimpleFiles<String, String>) -> Result<(), MainError> {
let args = CommandLineArguments::parse();
let syntax = Syntax::parse_file(file_database, &args.file)?;
let (mut errors, mut warnings) = syntax.validate();
let stop = !errors.is_empty();
let messages = errors
.drain(..)
.map(Into::into)
.chain(warnings.drain(..).map(Into::into));
let writer = StandardStream::stderr(ColorChoice::Auto);
let config = codespan_reporting::term::Config::default();
for message in messages {
term::emit(&mut writer.lock(), &config, file_database, &message).unwrap();
}
if stop {
return Ok(());
}
let ir = IR::from(syntax.simplify());
let mut backend = Backend::object_file(Triple::host())?;
backend.compile_function("gogogo", ir)?;
let bytes = backend.bytes()?;
std::fs::write(args.output.unwrap_or_else(|| "output.o".to_string()), bytes)?;
Ok(())
}
fn main() {
let mut file_database = SimpleFiles::new();
let args = CommandLineArguments::parse();
let mut compiler = ngr::Compiler::default();
match compile(&mut file_database) {
Ok(()) => {}
Err(e) => {
let writer = StandardStream::stderr(ColorChoice::Auto);
let config = codespan_reporting::term::Config::default();
let output_file = args.output.unwrap_or("output.o".to_string());
term::emit(
&mut writer.lock(),
&config,
&file_database,
&Diagnostic::from(e),
)
.unwrap();
}
if let Some(bytes) = compiler.compile(&args.file) {
std::fs::write(&output_file, bytes)
.unwrap_or_else(|x| eprintln!("Could not write to file {}: {}", output_file, x));
}
}

View File

@@ -1,130 +1,11 @@
use codespan_reporting::diagnostic::Diagnostic;
use codespan_reporting::files::SimpleFiles;
use codespan_reporting::term::{self, Config};
use cranelift_jit::JITModule;
use cranelift_module::ModuleError;
use ngr::backend::{Backend, BackendError};
use ngr::ir::Program as IR;
use ngr::syntax::{Location, ParserError, Statement};
use pretty::termcolor::{ColorChoice, StandardStream, WriteColor};
use ngr::backend::BackendError;
use rustyline::error::ReadlineError;
use rustyline::DefaultEditor;
use std::collections::HashMap;
pub struct RunLoop<'a> {
file_database: SimpleFiles<&'a str, String>,
jitter: Backend<JITModule>,
variable_binding_sites: HashMap<String, Location>,
gensym_index: usize,
writer: &'a mut dyn WriteColor,
config: Config,
}
#[allow(clippy::upper_case_acronyms)]
#[derive(Debug, thiserror::Error)]
enum REPLError {
#[error("Error parsing statement: {0}")]
Parser(#[from] ParserError),
#[error("JIT error: {0}")]
JIT(#[from] BackendError),
#[error("Internal cranelift error: {0}")]
Cranelift(#[from] ModuleError),
#[error(transparent)]
Reporting(#[from] codespan_reporting::files::Error),
}
impl From<REPLError> for Diagnostic<usize> {
fn from(value: REPLError) -> Self {
match value {
REPLError::Parser(err) => Diagnostic::from(&err),
REPLError::JIT(err) => Diagnostic::from(err),
REPLError::Cranelift(err) => Diagnostic::bug().with_message(format!("{}", err)),
REPLError::Reporting(err) => Diagnostic::bug().with_message(format!("{}", err)),
}
}
}
impl<'a> RunLoop<'a> {
pub fn new(writer: &'a mut dyn WriteColor, config: Config) -> Result<Self, BackendError> {
Ok(RunLoop {
file_database: SimpleFiles::new(),
jitter: Backend::jit(None)?,
variable_binding_sites: HashMap::new(),
gensym_index: 1,
writer,
config,
})
}
fn emit_diagnostic(
&mut self,
diagnostic: Diagnostic<usize>,
) -> Result<(), codespan_reporting::files::Error> {
term::emit(self.writer, &self.config, &self.file_database, &diagnostic)
}
fn process_input(&mut self, line_no: usize, command: String) {
if let Err(err) = self.process(line_no, command) {
if let Err(e) = self.emit_diagnostic(Diagnostic::from(err)) {
eprintln!(
"WOAH! System having trouble printing error messages. This is very bad. ({})",
e
);
}
}
}
fn process(&mut self, line_no: usize, command: String) -> Result<(), REPLError> {
let entry = self.file_database.add("entry", command);
let source = self
.file_database
.get(entry)
.expect("entry exists")
.source();
let syntax = Statement::parse(entry, source)?;
// if this is a variable binding, and we've never defined this variable before,
// we should tell cranelift about it. this is optimistic; if we fail to compile,
// then we won't use this definition until someone tries again.
if let Statement::Binding(_, ref name, _) = syntax {
if !self.variable_binding_sites.contains_key(name.as_str()) {
self.jitter.define_string(name)?;
self.jitter.define_variable(name.clone())?;
}
};
let (mut errors, mut warnings) = syntax.validate(&mut self.variable_binding_sites);
let stop = !errors.is_empty();
let messages = errors
.drain(..)
.map(Into::into)
.chain(warnings.drain(..).map(Into::into));
for message in messages {
self.emit_diagnostic(message)?;
}
if stop {
return Ok(());
}
let ir = IR::from(syntax.simplify(&mut self.gensym_index));
let name = format!("line{}", line_no);
let function_id = self.jitter.compile_function(&name, ir)?;
self.jitter.module.finalize_definitions()?;
let compiled_bytes = self.jitter.bytes(function_id);
let compiled_function = unsafe { std::mem::transmute::<_, fn() -> ()>(compiled_bytes) };
compiled_function();
Ok(())
}
}
fn main() -> Result<(), BackendError> {
let mut editor = DefaultEditor::new().expect("rustyline works");
let mut line_no = 0;
let mut writer = StandardStream::stdout(ColorChoice::Auto);
let config = codespan_reporting::term::Config::default();
let mut state = RunLoop::new(&mut writer, config)?;
let mut state = ngr::REPL::default();
println!("No Good Reason, the Interpreter!");
loop {
@@ -135,18 +16,30 @@ fn main() -> Result<(), BackendError> {
":quit" => break,
_ => state.process_input(line_no, command),
},
// it's not clear to me what this could be, but OK
Err(ReadlineError::Io(e)) => {
eprintln!("IO error: {}", e);
break;
}
// Control-D and Control-C
Err(ReadlineError::Eof) => break,
Err(ReadlineError::Interrupted) => break,
// For some reason this doesn't exist on Windows. I also don't quite know
// what would cause this, but ...
#[cfg(not(windows))]
Err(ReadlineError::Errno(e)) => {
eprintln!("Unknown syscall error: {}", e);
break;
}
// We don't actually do any reflow-ing if we change the terminal size,
// so we can just ignore this.
Err(ReadlineError::WindowResized) => continue,
// Why on earth are there so many error types?
Err(e) => {
eprintln!("Unknown internal error: {}", e);
break;