Adding upstream version 1.64.0+dfsg1.upstream/1.64.0+dfsg1

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 158 insertions, 0 deletions

diff --git a/src/tools/rust-analyzer/crates/ide/src/prime_caches.rs b/src/tools/rust-analyzer/crates/ide/src/prime_caches.rs
new file mode 100644
index 000000000..296270036
--- /dev/null
+++ b/src/tools/rust-analyzer/crates/ide/src/prime_caches.rs
@@ -0,0 +1,158 @@
+//! rust-analyzer is lazy and doesn't compute anything unless asked. This
+//! sometimes is counter productive when, for example, the first goto definition
+//! request takes longer to compute. This modules implemented prepopulation of
+//! various caches, it's not really advanced at the moment.
+mod topologic_sort;
+
+use std::time::Duration;
+
+use hir::db::DefDatabase;
+use ide_db::{
+    base_db::{
+        salsa::{Database, ParallelDatabase, Snapshot},
+        Cancelled, CrateGraph, CrateId, SourceDatabase, SourceDatabaseExt,
+    },
+    FxHashSet, FxIndexMap,
+};
+
+use crate::RootDatabase;
+
+/// We're indexing many crates.
+#[derive(Debug)]
+pub struct ParallelPrimeCachesProgress {
+    /// the crates that we are currently priming.
+    pub crates_currently_indexing: Vec<String>,
+    /// the total number of crates we want to prime.
+    pub crates_total: usize,
+    /// the total number of crates that have finished priming
+    pub crates_done: usize,
+}
+
+pub(crate) fn parallel_prime_caches(
+    db: &RootDatabase,
+    num_worker_threads: u8,
+    cb: &(dyn Fn(ParallelPrimeCachesProgress) + Sync),
+) {
+    let _p = profile::span("prime_caches");
+
+    let graph = db.crate_graph();
+    let mut crates_to_prime = {
+        let crate_ids = compute_crates_to_prime(db, &graph);
+
+        let mut builder = topologic_sort::TopologicalSortIter::builder();
+
+        for &crate_id in &crate_ids {
+            let crate_data = &graph[crate_id];
+            let dependencies = crate_data
+                .dependencies
+                .iter()
+                .map(|d| d.crate_id)
+                .filter(|i| crate_ids.contains(i));
+
+            builder.add(crate_id, dependencies);
+        }
+
+        builder.build()
+    };
+
+    enum ParallelPrimeCacheWorkerProgress {
+        BeginCrate { crate_id: CrateId, crate_name: String },
+        EndCrate { crate_id: CrateId },
+    }
+
+    let (work_sender, progress_receiver) = {
+        let (progress_sender, progress_receiver) = crossbeam_channel::unbounded();
+        let (work_sender, work_receiver) = crossbeam_channel::unbounded();
+        let prime_caches_worker = move |db: Snapshot<RootDatabase>| {
+            while let Ok((crate_id, crate_name)) = work_receiver.recv() {
+                progress_sender
+                    .send(ParallelPrimeCacheWorkerProgress::BeginCrate { crate_id, crate_name })?;
+
+                // This also computes the DefMap
+                db.import_map(crate_id);
+
+                progress_sender.send(ParallelPrimeCacheWorkerProgress::EndCrate { crate_id })?;
+            }
+
+            Ok::<_, crossbeam_channel::SendError<_>>(())
+        };
+
+        for _ in 0..num_worker_threads {
+            let worker = prime_caches_worker.clone();
+            let db = db.snapshot();
+            std::thread::spawn(move || Cancelled::catch(|| worker(db)));
+        }
+
+        (work_sender, progress_receiver)
+    };
+
+    let crates_total = crates_to_prime.pending();
+    let mut crates_done = 0;
+
+    // an index map is used to preserve ordering so we can sort the progress report in order of
+    // "longest crate to index" first
+    let mut crates_currently_indexing =
+        FxIndexMap::with_capacity_and_hasher(num_worker_threads as _, Default::default());
+
+    while crates_done < crates_total {
+        db.unwind_if_cancelled();
+
+        for crate_id in &mut crates_to_prime {
+            work_sender
+                .send((
+                    crate_id,
+                    graph[crate_id].display_name.as_deref().unwrap_or_default().to_string(),
+                ))
+                .ok();
+        }
+
+        // recv_timeout is somewhat a hack, we need a way to from this thread check to see if the current salsa revision
+        // is cancelled on a regular basis. workers will only exit if they are processing a task that is cancelled, or
+        // if this thread exits, and closes the work channel.
+        let worker_progress = match progress_receiver.recv_timeout(Duration::from_millis(10)) {
+            Ok(p) => p,
+            Err(crossbeam_channel::RecvTimeoutError::Timeout) => {
+                continue;
+            }
+            Err(crossbeam_channel::RecvTimeoutError::Disconnected) => {
+                // our workers may have died from a cancelled task, so we'll check and re-raise here.
+                db.unwind_if_cancelled();
+                break;
+            }
+        };
+        match worker_progress {
+            ParallelPrimeCacheWorkerProgress::BeginCrate { crate_id, crate_name } => {
+                crates_currently_indexing.insert(crate_id, crate_name);
+            }
+            ParallelPrimeCacheWorkerProgress::EndCrate { crate_id } => {
+                crates_currently_indexing.remove(&crate_id);
+                crates_to_prime.mark_done(crate_id);
+                crates_done += 1;
+            }
+        };
+
+        let progress = ParallelPrimeCachesProgress {
+            crates_currently_indexing: crates_currently_indexing.values().cloned().collect(),
+            crates_done,
+            crates_total,
+        };
+
+        cb(progress);
+    }
+}
+
+fn compute_crates_to_prime(db: &RootDatabase, graph: &CrateGraph) -> FxHashSet<CrateId> {
+    // We're only interested in the workspace crates and the `ImportMap`s of their direct
+    // dependencies, though in practice the latter also compute the `DefMap`s.
+    // We don't prime transitive dependencies because they're generally not visible in
+    // the current workspace.
+    graph
+        .iter()
+        .filter(|&id| {
+            let file_id = graph[id].root_file_id;
+            let root_id = db.file_source_root(file_id);
+            !db.source_root(root_id).is_library
+        })
+        .flat_map(|id| graph[id].dependencies.iter().map(|krate| krate.crate_id))
+        .collect()
+}