bjoernager/rust
bjoernager/rust
1
Fork 0
Code Issues Pull requests Activity

Auto merge of #115964 - bjorn3:cgu_reuse_tracker_global_state, r=cjgillot

Browse source 
Remove cgu_reuse_tracker from Session

This removes a bit of global mutable state.

It will now miss post-lto cgu reuse when ThinLTO determines that a cgu doesn't get changed, but there weren't any tests for this anyway and a test for it would be fragile to the exact implementation of ThinLTO in LLVM.
This commit is contained in:
bors 2023-10-13 00:09:30 +00:00
commit 130ff8cb6c
19 changed files with 274 additions and 322 deletions
Download patch file Download diff file Expand all files Collapse all files

171
compiler/rustc_incremental/src/assert_module_sources.rs
View file

@ -1,171 +0,0 @@
//! This pass is only used for UNIT TESTS related to incremental
//! compilation. It tests whether a particular `.o` file will be re-used
//! from a previous compilation or whether it must be regenerated.
//!
//! The user adds annotations to the crate of the following form:
//!
//! ```
//! # #![feature(rustc_attrs)]
//! # #![allow(internal_features)]
//! #![rustc_partition_reused(module="spike", cfg="rpass2")]
//! #![rustc_partition_codegened(module="spike-x", cfg="rpass2")]
//! ```
//!
//! The first indicates (in the cfg `rpass2`) that `spike.o` will be
//! reused, the second that `spike-x.o` will be recreated. If these
//! annotations are inaccurate, errors are reported.
//!
//! The reason that we use `cfg=...` and not `#[cfg_attr]` is so that
//! the HIR doesn't change as a result of the annotations, which might
//! perturb the reuse results.
//!
//! `#![rustc_expected_cgu_reuse(module="spike", cfg="rpass2", kind="post-lto")]`
//! allows for doing a more fine-grained check to see if pre- or post-lto data
//! was re-used.
use crate::errors;
use rustc_ast as ast;
use rustc_data_structures::unord::UnordSet;
use rustc_hir::def_id::LOCAL_CRATE;
use rustc_middle::mir::mono::CodegenUnitNameBuilder;
use rustc_middle::ty::TyCtxt;
use rustc_session::cgu_reuse_tracker::*;
use rustc_span::symbol::{sym, Symbol};
use thin_vec::ThinVec;
#[allow(missing_docs)]
pub fn assert_module_sources(tcx: TyCtxt<'_>) {
tcx.dep_graph.with_ignore(|| {
if tcx.sess.opts.incremental.is_none() {
return;
}
let available_cgus =
tcx.collect_and_partition_mono_items(()).1.iter().map(|cgu| cgu.name()).collect();
let ams = AssertModuleSource { tcx, available_cgus };
for attr in tcx.hir().attrs(rustc_hir::CRATE_HIR_ID) {
ams.check_attr(attr);
}
})
}
struct AssertModuleSource<'tcx> {
tcx: TyCtxt<'tcx>,
available_cgus: UnordSet<Symbol>,
}
impl<'tcx> AssertModuleSource<'tcx> {
fn check_attr(&self, attr: &ast::Attribute) {
let (expected_reuse, comp_kind) = if attr.has_name(sym::rustc_partition_reused) {
(CguReuse::PreLto, ComparisonKind::AtLeast)
} else if attr.has_name(sym::rustc_partition_codegened) {
(CguReuse::No, ComparisonKind::Exact)
} else if attr.has_name(sym::rustc_expected_cgu_reuse) {
match self.field(attr, sym::kind) {
sym::no => (CguReuse::No, ComparisonKind::Exact),
sym::pre_dash_lto => (CguReuse::PreLto, ComparisonKind::Exact),
sym::post_dash_lto => (CguReuse::PostLto, ComparisonKind::Exact),
sym::any => (CguReuse::PreLto, ComparisonKind::AtLeast),
other => {
self.tcx
.sess
.emit_fatal(errors::UnknownReuseKind { span: attr.span, kind: other });
}
}
} else {
return;
};
if !self.tcx.sess.opts.unstable_opts.query_dep_graph {
self.tcx.sess.emit_fatal(errors::MissingQueryDepGraph { span: attr.span });
}
if !self.check_config(attr) {
debug!("check_attr: config does not match, ignoring attr");
return;
}
let user_path = self.field(attr, sym::module).to_string();
let crate_name = self.tcx.crate_name(LOCAL_CRATE).to_string();
if !user_path.starts_with(&crate_name) {
self.tcx.sess.emit_fatal(errors::MalformedCguName {
span: attr.span,
user_path,
crate_name,
});
}
// Split of the "special suffix" if there is one.
let (user_path, cgu_special_suffix) = if let Some(index) = user_path.rfind('.') {
(&user_path[..index], Some(&user_path[index + 1..]))
} else {
(&user_path[..], None)
};
let mut iter = user_path.split('-');
// Remove the crate name
assert_eq!(iter.next().unwrap(), crate_name);
let cgu_path_components = iter.collect::<Vec<_>>();
let cgu_name_builder = &mut CodegenUnitNameBuilder::new(self.tcx);
let cgu_name =
cgu_name_builder.build_cgu_name(LOCAL_CRATE, cgu_path_components, cgu_special_suffix);
debug!("mapping '{}' to cgu name '{}'", self.field(attr, sym::module), cgu_name);
if !self.available_cgus.contains(&cgu_name) {
let cgu_names: Vec<&str> =
self.available_cgus.items().map(|cgu| cgu.as_str()).into_sorted_stable_ord();
self.tcx.sess.emit_err(errors::NoModuleNamed {
span: attr.span,
user_path,
cgu_name,
cgu_names: cgu_names.join(", "),
});
}
self.tcx.sess.cgu_reuse_tracker.set_expectation(
cgu_name,
&user_path,
attr.span,
expected_reuse,
comp_kind,
);
}
fn field(&self, attr: &ast::Attribute, name: Symbol) -> Symbol {
for item in attr.meta_item_list().unwrap_or_else(ThinVec::new) {
if item.has_name(name) {
if let Some(value) = item.value_str() {
return value;
} else {
self.tcx.sess.emit_fatal(errors::FieldAssociatedValueExpected {
span: item.span(),
name,
});
}
}
}
self.tcx.sess.emit_fatal(errors::NoField { span: attr.span, name });
}
/// Scan for a `cfg="foo"` attribute and check whether we have a
/// cfg flag called `foo`.
fn check_config(&self, attr: &ast::Attribute) -> bool {
let config = &self.tcx.sess.parse_sess.config;
let value = self.field(attr, sym::cfg);
debug!("check_config(config={:?}, value={:?})", config, value);
if config.iter().any(|&(name, _)| name == value) {
debug!("check_config: matched");
return true;
}
debug!("check_config: no match found");
false
}
}

50
compiler/rustc_incremental/src/errors.rs
View file

@ -40,56 +40,6 @@ pub struct NoPath {
pub source: String,
}
#[derive(Diagnostic)]
#[diag(incremental_unknown_reuse_kind)]
pub struct UnknownReuseKind {
#[primary_span]
pub span: Span,
pub kind: Symbol,
}
#[derive(Diagnostic)]
#[diag(incremental_missing_query_depgraph)]
pub struct MissingQueryDepGraph {
#[primary_span]
pub span: Span,
}
#[derive(Diagnostic)]
#[diag(incremental_malformed_cgu_name)]
pub struct MalformedCguName {
#[primary_span]
pub span: Span,
pub user_path: String,
pub crate_name: String,
}
#[derive(Diagnostic)]
#[diag(incremental_no_module_named)]
pub struct NoModuleNamed<'a> {
#[primary_span]
pub span: Span,
pub user_path: &'a str,
pub cgu_name: Symbol,
pub cgu_names: String,
}
#[derive(Diagnostic)]
#[diag(incremental_field_associated_value_expected)]
pub struct FieldAssociatedValueExpected {
#[primary_span]
pub span: Span,
pub name: Symbol,
}
#[derive(Diagnostic)]
#[diag(incremental_no_field)]
pub struct NoField {
#[primary_span]
pub span: Span,
pub name: Symbol,
}
#[derive(Diagnostic)]
#[diag(incremental_assertion_auto)]
pub struct AssertionAuto<'a> {

1
compiler/rustc_incremental/src/lib.rs
View file

@ -16,7 +16,6 @@ extern crate rustc_middle;
extern crate tracing;
mod assert_dep_graph;
pub mod assert_module_sources;
mod errors;
mod persist;