rust/src/pretty_clif.rs

279 lines
8.0 KiB
Rust

//! This module provides the [CommentWriter] which makes it possible
//! to add comments to the written cranelift ir.
//!
//! # Example
//!
//! ```clif
//! test compile
//! target x86_64
//!
//! function u0:0(i64, i64, i64) system_v {
//! ; symbol _ZN119_$LT$example..IsNotEmpty$u20$as$u20$mini_core..FnOnce$LT$$LP$$RF$$u27$a$u20$$RF$$u27$b$u20$$u5b$u16$u5d$$C$$RP$$GT$$GT$9call_once17he85059d5e6a760a0E
//! ; instance Instance { def: Item(DefId(0/0:29 ~ example[8787]::{{impl}}[0]::call_once[0])), substs: [ReErased, ReErased] }
//! ; sig ([IsNotEmpty, (&&[u16],)]; c_variadic: false)->(u8, u8)
//!
//! ; ssa {_2: NOT_SSA, _4: NOT_SSA, _0: NOT_SSA, _3: (empty), _1: NOT_SSA}
//! ; msg loc.idx param pass mode ssa flags ty
//! ; ret _0 = v0 ByRef NOT_SSA (u8, u8)
//! ; arg _1 = v1 ByRef NOT_SSA IsNotEmpty
//! ; arg _2.0 = v2 ByVal(types::I64) NOT_SSA &&[u16]
//!
//! ss0 = explicit_slot 0 ; _1: IsNotEmpty size=0 align=1,8
//! ss1 = explicit_slot 8 ; _2: (&&[u16],) size=8 align=8,8
//! ss2 = explicit_slot 8 ; _4: (&&[u16],) size=8 align=8,8
//! sig0 = (i64, i64, i64) system_v
//! sig1 = (i64, i64, i64) system_v
//! fn0 = colocated u0:6 sig1 ; Instance { def: Item(DefId(0/0:31 ~ example[8787]::{{impl}}[1]::call_mut[0])), substs: [ReErased, ReErased] }
//!
//! block0(v0: i64, v1: i64, v2: i64):
//! v3 = stack_addr.i64 ss0
//! v4 = stack_addr.i64 ss1
//! store v2, v4
//! v5 = stack_addr.i64 ss2
//! jump block1
//!
//! block1:
//! nop
//! ; _3 = &mut _1
//! ; _4 = _2
//! v6 = load.i64 v4
//! store v6, v5
//! ;
//! ; _0 = const mini_core::FnMut::call_mut(move _3, move _4)
//! v7 = load.i64 v5
//! call fn0(v0, v3, v7)
//! jump block2
//!
//! block2:
//! nop
//! ;
//! ; return
//! return
//! }
//! ```
use std::fmt;
use std::io::Write;
use cranelift_codegen::{
entity::SecondaryMap,
ir::entities::AnyEntity,
write::{FuncWriter, PlainWriter},
};
use rustc_middle::ty::layout::FnAbiOf;
use rustc_session::config::OutputType;
use crate::prelude::*;
#[derive(Clone, Debug)]
pub(crate) struct CommentWriter {
enabled: bool,
global_comments: Vec<String>,
entity_comments: FxHashMap<AnyEntity, String>,
}
impl CommentWriter {
pub(crate) fn new<'tcx>(tcx: TyCtxt<'tcx>, instance: Instance<'tcx>) -> Self {
let enabled = should_write_ir(tcx);
let global_comments = if enabled {
vec![
format!("symbol {}", tcx.symbol_name(instance).name),
format!("instance {:?}", instance),
format!(
"abi {:?}",
RevealAllLayoutCx(tcx).fn_abi_of_instance(instance, ty::List::empty())
),
String::new(),
]
} else {
vec![]
};
CommentWriter { enabled, global_comments, entity_comments: FxHashMap::default() }
}
}
impl CommentWriter {
pub(crate) fn enabled(&self) -> bool {
self.enabled
}
pub(crate) fn add_global_comment<S: Into<String>>(&mut self, comment: S) {
debug_assert!(self.enabled);
self.global_comments.push(comment.into());
}
pub(crate) fn add_comment<S: Into<String> + AsRef<str>, E: Into<AnyEntity>>(
&mut self,
entity: E,
comment: S,
) {
debug_assert!(self.enabled);
use std::collections::hash_map::Entry;
match self.entity_comments.entry(entity.into()) {
Entry::Occupied(mut occ) => {
occ.get_mut().push('\n');
occ.get_mut().push_str(comment.as_ref());
}
Entry::Vacant(vac) => {
vac.insert(comment.into());
}
}
}
}
impl FuncWriter for &'_ CommentWriter {
fn write_preamble(
&mut self,
w: &mut dyn fmt::Write,
func: &Function,
) -> Result<bool, fmt::Error> {
for comment in &self.global_comments {
if !comment.is_empty() {
writeln!(w, "; {}", comment)?;
} else {
writeln!(w)?;
}
}
if !self.global_comments.is_empty() {
writeln!(w)?;
}
self.super_preamble(w, func)
}
fn write_entity_definition(
&mut self,
w: &mut dyn fmt::Write,
_func: &Function,
entity: AnyEntity,
value: &dyn fmt::Display,
) -> fmt::Result {
write!(w, " {} = {}", entity, value)?;
if let Some(comment) = self.entity_comments.get(&entity) {
writeln!(w, " ; {}", comment.replace('\n', "\n; "))
} else {
writeln!(w)
}
}
fn write_block_header(
&mut self,
w: &mut dyn fmt::Write,
func: &Function,
block: Block,
indent: usize,
) -> fmt::Result {
PlainWriter.write_block_header(w, func, block, indent)
}
fn write_instruction(
&mut self,
w: &mut dyn fmt::Write,
func: &Function,
aliases: &SecondaryMap<Value, Vec<Value>>,
inst: Inst,
indent: usize,
) -> fmt::Result {
PlainWriter.write_instruction(w, func, aliases, inst, indent)?;
if let Some(comment) = self.entity_comments.get(&inst.into()) {
writeln!(w, "; {}", comment.replace('\n', "\n; "))?;
}
Ok(())
}
}
impl FunctionCx<'_, '_, '_> {
pub(crate) fn add_global_comment<S: Into<String>>(&mut self, comment: S) {
self.clif_comments.add_global_comment(comment);
}
pub(crate) fn add_comment<S: Into<String> + AsRef<str>, E: Into<AnyEntity>>(
&mut self,
entity: E,
comment: S,
) {
self.clif_comments.add_comment(entity, comment);
}
}
pub(crate) fn should_write_ir(tcx: TyCtxt<'_>) -> bool {
tcx.sess.opts.output_types.contains_key(&OutputType::LlvmAssembly)
}
pub(crate) fn write_ir_file(
tcx: TyCtxt<'_>,
name: impl FnOnce() -> String,
write: impl FnOnce(&mut dyn Write) -> std::io::Result<()>,
) {
if !should_write_ir(tcx) {
return;
}
let clif_output_dir = tcx.output_filenames(()).with_extension("clif");
match std::fs::create_dir(&clif_output_dir) {
Ok(()) => {}
Err(err) if err.kind() == std::io::ErrorKind::AlreadyExists => {}
res @ Err(_) => res.unwrap(),
}
let clif_file_name = clif_output_dir.join(name());
let res = std::fs::File::create(clif_file_name).and_then(|mut file| write(&mut file));
if let Err(err) = res {
tcx.sess.warn(&format!("error writing ir file: {}", err));
}
}
pub(crate) fn write_clif_file<'tcx>(
tcx: TyCtxt<'tcx>,
postfix: &str,
isa: &dyn cranelift_codegen::isa::TargetIsa,
instance: Instance<'tcx>,
func: &cranelift_codegen::ir::Function,
mut clif_comments: &CommentWriter,
) {
// FIXME work around filename too long errors
write_ir_file(
tcx,
|| format!("{}.{}.clif", tcx.symbol_name(instance).name, postfix),
|file| {
let mut clif = String::new();
cranelift_codegen::write::decorate_function(&mut clif_comments, &mut clif, func)
.unwrap();
for flag in isa.flags().iter() {
writeln!(file, "set {}", flag)?;
}
write!(file, "target {}", isa.triple().architecture.to_string())?;
for isa_flag in isa.isa_flags().iter() {
write!(file, " {}", isa_flag)?;
}
writeln!(file, "\n")?;
writeln!(file)?;
file.write_all(clif.as_bytes())?;
Ok(())
},
);
}
impl fmt::Debug for FunctionCx<'_, '_, '_> {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
writeln!(f, "{:?}", self.instance.substs)?;
writeln!(f, "{:?}", self.local_map)?;
let mut clif = String::new();
::cranelift_codegen::write::decorate_function(
&mut &self.clif_comments,
&mut clif,
&self.bcx.func,
)
.unwrap();
writeln!(f, "\n{}", clif)
}
}