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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-18 02:49:50 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-18 02:49:50 +0000
commit9835e2ae736235810b4ea1c162ca5e65c547e770 (patch)
tree3fcebf40ed70e581d776a8a4c65923e8ec20e026 /compiler/rustc_monomorphize/src/partitioning/merging.rs
parentReleasing progress-linux version 1.70.0+dfsg2-1~progress7.99u1. (diff)
downloadrustc-9835e2ae736235810b4ea1c162ca5e65c547e770.tar.xz
rustc-9835e2ae736235810b4ea1c162ca5e65c547e770.zip
Merging upstream version 1.71.1+dfsg1.
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'compiler/rustc_monomorphize/src/partitioning/merging.rs')
-rw-r--r--compiler/rustc_monomorphize/src/partitioning/merging.rs111
1 files changed, 0 insertions, 111 deletions
diff --git a/compiler/rustc_monomorphize/src/partitioning/merging.rs b/compiler/rustc_monomorphize/src/partitioning/merging.rs
deleted file mode 100644
index 5c524a184..000000000
--- a/compiler/rustc_monomorphize/src/partitioning/merging.rs
+++ /dev/null
@@ -1,111 +0,0 @@
-use std::cmp;
-
-use rustc_data_structures::fx::FxHashMap;
-use rustc_hir::def_id::LOCAL_CRATE;
-use rustc_middle::mir::mono::{CodegenUnit, CodegenUnitNameBuilder};
-use rustc_span::symbol::Symbol;
-
-use super::PartitioningCx;
-use crate::partitioning::PreInliningPartitioning;
-
-pub fn merge_codegen_units<'tcx>(
- cx: &PartitioningCx<'_, 'tcx>,
- initial_partitioning: &mut PreInliningPartitioning<'tcx>,
-) {
- assert!(cx.target_cgu_count >= 1);
- let codegen_units = &mut initial_partitioning.codegen_units;
-
- // Note that at this point in time the `codegen_units` here may not be in a
- // deterministic order (but we know they're deterministically the same set).
- // We want this merging to produce a deterministic ordering of codegen units
- // from the input.
- //
- // Due to basically how we've implemented the merging below (merge the two
- // smallest into each other) we're sure to start off with a deterministic
- // order (sorted by name). This'll mean that if two cgus have the same size
- // the stable sort below will keep everything nice and deterministic.
- codegen_units.sort_by(|a, b| a.name().as_str().cmp(b.name().as_str()));
-
- // This map keeps track of what got merged into what.
- let mut cgu_contents: FxHashMap<Symbol, Vec<Symbol>> =
- codegen_units.iter().map(|cgu| (cgu.name(), vec![cgu.name()])).collect();
-
- // Merge the two smallest codegen units until the target size is reached.
- while codegen_units.len() > cx.target_cgu_count {
- // Sort small cgus to the back
- codegen_units.sort_by_cached_key(|cgu| cmp::Reverse(cgu.size_estimate()));
- let mut smallest = codegen_units.pop().unwrap();
- let second_smallest = codegen_units.last_mut().unwrap();
-
- // Move the mono-items from `smallest` to `second_smallest`
- second_smallest.modify_size_estimate(smallest.size_estimate());
- for (k, v) in smallest.items_mut().drain() {
- second_smallest.items_mut().insert(k, v);
- }
-
- // Record that `second_smallest` now contains all the stuff that was in
- // `smallest` before.
- let mut consumed_cgu_names = cgu_contents.remove(&smallest.name()).unwrap();
- cgu_contents.get_mut(&second_smallest.name()).unwrap().append(&mut consumed_cgu_names);
-
- debug!(
- "CodegenUnit {} merged into CodegenUnit {}",
- smallest.name(),
- second_smallest.name()
- );
- }
-
- let cgu_name_builder = &mut CodegenUnitNameBuilder::new(cx.tcx);
-
- if cx.tcx.sess.opts.incremental.is_some() {
- // If we are doing incremental compilation, we want CGU names to
- // reflect the path of the source level module they correspond to.
- // For CGUs that contain the code of multiple modules because of the
- // merging done above, we use a concatenation of the names of
- // all contained CGUs.
- let new_cgu_names: FxHashMap<Symbol, String> = cgu_contents
- .into_iter()
- // This `filter` makes sure we only update the name of CGUs that
- // were actually modified by merging.
- .filter(|(_, cgu_contents)| cgu_contents.len() > 1)
- .map(|(current_cgu_name, cgu_contents)| {
- let mut cgu_contents: Vec<&str> = cgu_contents.iter().map(|s| s.as_str()).collect();
-
- // Sort the names, so things are deterministic and easy to
- // predict.
-
- // We are sorting primitive &strs here so we can use unstable sort
- cgu_contents.sort_unstable();
-
- (current_cgu_name, cgu_contents.join("--"))
- })
- .collect();
-
- for cgu in codegen_units.iter_mut() {
- if let Some(new_cgu_name) = new_cgu_names.get(&cgu.name()) {
- if cx.tcx.sess.opts.unstable_opts.human_readable_cgu_names {
- cgu.set_name(Symbol::intern(&new_cgu_name));
- } else {
- // If we don't require CGU names to be human-readable, we
- // use a fixed length hash of the composite CGU name
- // instead.
- let new_cgu_name = CodegenUnit::mangle_name(&new_cgu_name);
- cgu.set_name(Symbol::intern(&new_cgu_name));
- }
- }
- }
- } else {
- // If we are compiling non-incrementally we just generate simple CGU
- // names containing an index.
- for (index, cgu) in codegen_units.iter_mut().enumerate() {
- cgu.set_name(numbered_codegen_unit_name(cgu_name_builder, index));
- }
- }
-}
-
-fn numbered_codegen_unit_name(
- name_builder: &mut CodegenUnitNameBuilder<'_>,
- index: usize,
-) -> Symbol {
- name_builder.build_cgu_name_no_mangle(LOCAL_CRATE, &["cgu"], Some(index))
-}