2 files changed, 387 insertions, 0 deletions

diff --git a/crates/ra_ide/src/ide_db/change.rs b/crates/ra_ide/src/ide_db/change.rs
new file mode 100644
index 000000000..62ffa6920
--- /dev/null
+++ b/crates/ra_ide/src/ide_db/change.rs
@@ -0,0 +1,386 @@
+//! FIXME: write short doc here
+
+use std::{fmt, sync::Arc, time};
+
+use ra_db::{
+    salsa::{Database, Durability, SweepStrategy},
+    CrateGraph, CrateId, FileId, RelativePathBuf, SourceDatabase, SourceDatabaseExt, SourceRoot,
+    SourceRootId,
+};
+use ra_prof::{memory_usage, profile, Bytes};
+use ra_syntax::SourceFile;
+#[cfg(not(feature = "wasm"))]
+use rayon::prelude::*;
+use rustc_hash::FxHashMap;
+
+use crate::ide_db::{
+    symbol_index::{SymbolIndex, SymbolsDatabase},
+    DebugData, RootDatabase,
+};
+
+#[derive(Default)]
+pub struct AnalysisChange {
+    new_roots: Vec<(SourceRootId, bool)>,
+    roots_changed: FxHashMap<SourceRootId, RootChange>,
+    files_changed: Vec<(FileId, Arc<String>)>,
+    libraries_added: Vec<LibraryData>,
+    crate_graph: Option<CrateGraph>,
+    debug_data: DebugData,
+}
+
+impl fmt::Debug for AnalysisChange {
+    fn fmt(&self, fmt: &mut fmt::Formatter) -> fmt::Result {
+        let mut d = fmt.debug_struct("AnalysisChange");
+        if !self.new_roots.is_empty() {
+            d.field("new_roots", &self.new_roots);
+        }
+        if !self.roots_changed.is_empty() {
+            d.field("roots_changed", &self.roots_changed);
+        }
+        if !self.files_changed.is_empty() {
+            d.field("files_changed", &self.files_changed.len());
+        }
+        if !self.libraries_added.is_empty() {
+            d.field("libraries_added", &self.libraries_added.len());
+        }
+        if !self.crate_graph.is_none() {
+            d.field("crate_graph", &self.crate_graph);
+        }
+        d.finish()
+    }
+}
+
+impl AnalysisChange {
+    pub fn new() -> AnalysisChange {
+        AnalysisChange::default()
+    }
+
+    pub fn add_root(&mut self, root_id: SourceRootId, is_local: bool) {
+        self.new_roots.push((root_id, is_local));
+    }
+
+    pub fn add_file(
+        &mut self,
+        root_id: SourceRootId,
+        file_id: FileId,
+        path: RelativePathBuf,
+        text: Arc<String>,
+    ) {
+        let file = AddFile { file_id, path, text };
+        self.roots_changed.entry(root_id).or_default().added.push(file);
+    }
+
+    pub fn change_file(&mut self, file_id: FileId, new_text: Arc<String>) {
+        self.files_changed.push((file_id, new_text))
+    }
+
+    pub fn remove_file(&mut self, root_id: SourceRootId, file_id: FileId, path: RelativePathBuf) {
+        let file = RemoveFile { file_id, path };
+        self.roots_changed.entry(root_id).or_default().removed.push(file);
+    }
+
+    pub fn add_library(&mut self, data: LibraryData) {
+        self.libraries_added.push(data)
+    }
+
+    pub fn set_crate_graph(&mut self, graph: CrateGraph) {
+        self.crate_graph = Some(graph);
+    }
+
+    pub fn set_debug_crate_name(&mut self, crate_id: CrateId, name: String) {
+        self.debug_data.crate_names.insert(crate_id, name);
+    }
+
+    pub fn set_debug_root_path(&mut self, source_root_id: SourceRootId, path: String) {
+        self.debug_data.root_paths.insert(source_root_id, path);
+    }
+}
+
+#[derive(Debug)]
+struct AddFile {
+    file_id: FileId,
+    path: RelativePathBuf,
+    text: Arc<String>,
+}
+
+#[derive(Debug)]
+struct RemoveFile {
+    file_id: FileId,
+    path: RelativePathBuf,
+}
+
+#[derive(Default)]
+struct RootChange {
+    added: Vec<AddFile>,
+    removed: Vec<RemoveFile>,
+}
+
+impl fmt::Debug for RootChange {
+    fn fmt(&self, fmt: &mut fmt::Formatter) -> fmt::Result {
+        fmt.debug_struct("AnalysisChange")
+            .field("added", &self.added.len())
+            .field("removed", &self.removed.len())
+            .finish()
+    }
+}
+
+pub struct LibraryData {
+    root_id: SourceRootId,
+    root_change: RootChange,
+    symbol_index: SymbolIndex,
+}
+
+impl fmt::Debug for LibraryData {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        f.debug_struct("LibraryData")
+            .field("root_id", &self.root_id)
+            .field("root_change", &self.root_change)
+            .field("n_symbols", &self.symbol_index.len())
+            .finish()
+    }
+}
+
+impl LibraryData {
+    pub fn prepare(
+        root_id: SourceRootId,
+        files: Vec<(FileId, RelativePathBuf, Arc<String>)>,
+    ) -> LibraryData {
+        let _p = profile("LibraryData::prepare");
+
+        #[cfg(not(feature = "wasm"))]
+        let iter = files.par_iter();
+        #[cfg(feature = "wasm")]
+        let iter = files.iter();
+
+        let symbol_index = SymbolIndex::for_files(iter.map(|(file_id, _, text)| {
+            let parse = SourceFile::parse(text);
+            (*file_id, parse)
+        }));
+        let mut root_change = RootChange::default();
+        root_change.added = files
+            .into_iter()
+            .map(|(file_id, path, text)| AddFile { file_id, path, text })
+            .collect();
+        LibraryData { root_id, root_change, symbol_index }
+    }
+}
+
+const GC_COOLDOWN: time::Duration = time::Duration::from_millis(100);
+
+impl RootDatabase {
+    pub(crate) fn request_cancellation(&mut self) {
+        let _p = profile("RootDatabase::request_cancellation");
+        self.salsa_runtime_mut().synthetic_write(Durability::LOW);
+    }
+
+    pub(crate) fn apply_change(&mut self, change: AnalysisChange) {
+        let _p = profile("RootDatabase::apply_change");
+        self.request_cancellation();
+        log::info!("apply_change {:?}", change);
+        if !change.new_roots.is_empty() {
+            let mut local_roots = Vec::clone(&self.local_roots());
+            for (root_id, is_local) in change.new_roots {
+                let root =
+                    if is_local { SourceRoot::new_local() } else { SourceRoot::new_library() };
+                let durability = durability(&root);
+                self.set_source_root_with_durability(root_id, Arc::new(root), durability);
+                if is_local {
+                    local_roots.push(root_id);
+                }
+            }
+            self.set_local_roots_with_durability(Arc::new(local_roots), Durability::HIGH);
+        }
+
+        for (root_id, root_change) in change.roots_changed {
+            self.apply_root_change(root_id, root_change);
+        }
+        for (file_id, text) in change.files_changed {
+            let source_root_id = self.file_source_root(file_id);
+            let source_root = self.source_root(source_root_id);
+            let durability = durability(&source_root);
+            self.set_file_text_with_durability(file_id, text, durability)
+        }
+        if !change.libraries_added.is_empty() {
+            let mut libraries = Vec::clone(&self.library_roots());
+            for library in change.libraries_added {
+                libraries.push(library.root_id);
+                self.set_source_root_with_durability(
+                    library.root_id,
+                    Arc::new(SourceRoot::new_library()),
+                    Durability::HIGH,
+                );
+                self.set_library_symbols_with_durability(
+                    library.root_id,
+                    Arc::new(library.symbol_index),
+                    Durability::HIGH,
+                );
+                self.apply_root_change(library.root_id, library.root_change);
+            }
+            self.set_library_roots_with_durability(Arc::new(libraries), Durability::HIGH);
+        }
+        if let Some(crate_graph) = change.crate_graph {
+            self.set_crate_graph_with_durability(Arc::new(crate_graph), Durability::HIGH)
+        }
+
+        Arc::make_mut(&mut self.debug_data).merge(change.debug_data)
+    }
+
+    fn apply_root_change(&mut self, root_id: SourceRootId, root_change: RootChange) {
+        let mut source_root = SourceRoot::clone(&self.source_root(root_id));
+        let durability = durability(&source_root);
+        for add_file in root_change.added {
+            self.set_file_text_with_durability(add_file.file_id, add_file.text, durability);
+            self.set_file_relative_path_with_durability(
+                add_file.file_id,
+                add_file.path.clone(),
+                durability,
+            );
+            self.set_file_source_root_with_durability(add_file.file_id, root_id, durability);
+            source_root.insert_file(add_file.path, add_file.file_id);
+        }
+        for remove_file in root_change.removed {
+            self.set_file_text_with_durability(remove_file.file_id, Default::default(), durability);
+            source_root.remove_file(&remove_file.path);
+        }
+        self.set_source_root_with_durability(root_id, Arc::new(source_root), durability);
+    }
+
+    pub(crate) fn maybe_collect_garbage(&mut self) {
+        if cfg!(feature = "wasm") {
+            return;
+        }
+
+        if self.last_gc_check.elapsed() > GC_COOLDOWN {
+            self.last_gc_check = crate::wasm_shims::Instant::now();
+        }
+    }
+
+    pub(crate) fn collect_garbage(&mut self) {
+        if cfg!(feature = "wasm") {
+            return;
+        }
+
+        let _p = profile("RootDatabase::collect_garbage");
+        self.last_gc = crate::wasm_shims::Instant::now();
+
+        let sweep = SweepStrategy::default().discard_values().sweep_all_revisions();
+
+        self.query(ra_db::ParseQuery).sweep(sweep);
+        self.query(hir::db::ParseMacroQuery).sweep(sweep);
+
+        // Macros do take significant space, but less then the syntax trees
+        // self.query(hir::db::MacroDefQuery).sweep(sweep);
+        // self.query(hir::db::MacroArgQuery).sweep(sweep);
+        // self.query(hir::db::MacroExpandQuery).sweep(sweep);
+
+        self.query(hir::db::AstIdMapQuery).sweep(sweep);
+
+        self.query(hir::db::BodyWithSourceMapQuery).sweep(sweep);
+
+        self.query(hir::db::ExprScopesQuery).sweep(sweep);
+        self.query(hir::db::DoInferQuery).sweep(sweep);
+        self.query(hir::db::BodyQuery).sweep(sweep);
+    }
+
+    pub(crate) fn per_query_memory_usage(&mut self) -> Vec<(String, Bytes)> {
+        let mut acc: Vec<(String, Bytes)> = vec![];
+        let sweep = SweepStrategy::default().discard_values().sweep_all_revisions();
+        macro_rules! sweep_each_query {
+            ($($q:path)*) => {$(
+                let before = memory_usage().allocated;
+                self.query($q).sweep(sweep);
+                let after = memory_usage().allocated;
+                let q: $q = Default::default();
+                let name = format!("{:?}", q);
+                acc.push((name, before - after));
+
+                let before = memory_usage().allocated;
+                self.query($q).sweep(sweep.discard_everything());
+                let after = memory_usage().allocated;
+                let q: $q = Default::default();
+                let name = format!("{:?} (deps)", q);
+                acc.push((name, before - after));
+            )*}
+        }
+        sweep_each_query![
+            // SourceDatabase
+            ra_db::ParseQuery
+            ra_db::SourceRootCratesQuery
+
+            // AstDatabase
+            hir::db::AstIdMapQuery
+            hir::db::InternMacroQuery
+            hir::db::MacroArgQuery
+            hir::db::MacroDefQuery
+            hir::db::ParseMacroQuery
+            hir::db::MacroExpandQuery
+
+            // DefDatabase
+            hir::db::RawItemsQuery
+            hir::db::ComputeCrateDefMapQuery
+            hir::db::StructDataQuery
+            hir::db::UnionDataQuery
+            hir::db::EnumDataQuery
+            hir::db::ImplDataQuery
+            hir::db::TraitDataQuery
+            hir::db::TypeAliasDataQuery
+            hir::db::FunctionDataQuery
+            hir::db::ConstDataQuery
+            hir::db::StaticDataQuery
+            hir::db::BodyWithSourceMapQuery
+            hir::db::BodyQuery
+            hir::db::ExprScopesQuery
+            hir::db::GenericParamsQuery
+            hir::db::AttrsQuery
+            hir::db::ModuleLangItemsQuery
+            hir::db::CrateLangItemsQuery
+            hir::db::LangItemQuery
+            hir::db::DocumentationQuery
+
+            // InternDatabase
+            hir::db::InternFunctionQuery
+            hir::db::InternStructQuery
+            hir::db::InternUnionQuery
+            hir::db::InternEnumQuery
+            hir::db::InternConstQuery
+            hir::db::InternStaticQuery
+            hir::db::InternTraitQuery
+            hir::db::InternTypeAliasQuery
+            hir::db::InternImplQuery
+
+            // HirDatabase
+            hir::db::DoInferQuery
+            hir::db::TyQuery
+            hir::db::ValueTyQuery
+            hir::db::ImplSelfTyQuery
+            hir::db::ImplTraitQuery
+            hir::db::FieldTypesQuery
+            hir::db::CallableItemSignatureQuery
+            hir::db::GenericPredicatesForParamQuery
+            hir::db::GenericPredicatesQuery
+            hir::db::GenericDefaultsQuery
+            hir::db::ImplsInCrateQuery
+            hir::db::ImplsForTraitQuery
+            hir::db::TraitSolverQuery
+            hir::db::InternTypeCtorQuery
+            hir::db::InternChalkImplQuery
+            hir::db::InternAssocTyValueQuery
+            hir::db::AssociatedTyDataQuery
+            hir::db::AssociatedTyValueQuery
+            hir::db::TraitSolveQuery
+            hir::db::TraitDatumQuery
+            hir::db::StructDatumQuery
+            hir::db::ImplDatumQuery
+        ];
+        acc.sort_by_key(|it| std::cmp::Reverse(it.1));
+        acc
+    }
+}
+
+fn durability(source_root: &SourceRoot) -> Durability {
+    if source_root.is_library {
+        Durability::HIGH
+    } else {
+        Durability::LOW
+    }
+}
diff --git a/crates/ra_ide/src/ide_db/mod.rs b/crates/ra_ide/src/ide_db/mod.rs
index 924ee9968..0df4d510f 100644
--- a/crates/ra_ide/src/ide_db/mod.rs
+++ b/crates/ra_ide/src/ide_db/mod.rs
@@ -4,6 +4,7 @@ pub mod line_index;
 pub mod line_index_utils;
 pub mod feature_flags;
 pub mod symbol_index;
+pub mod change;
 
 use std::sync::Arc;