1 // Copyright 2014 The Rust Project Developers. See the COPYRIGHT
2 // file at the top-level directory of this distribution and at
3 // http://rust-lang.org/COPYRIGHT.
5 // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
6 // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
7 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
8 // option. This file may not be copied, modified, or distributed
9 // except according to those terms.
11 use errors::DiagnosticBuilder;
12 use rustc_data_structures::stable_hasher::{HashStable, StableHasher};
13 use rustc_data_structures::fx::{FxHashMap, FxHashSet};
14 use rustc_data_structures::indexed_vec::{Idx, IndexVec};
15 use rustc_data_structures::sync::{Lrc, RwLock, ReadGuard, Lock};
18 use ty::{self, TyCtxt};
19 use util::common::{ProfileQueriesMsg, profq_msg};
21 use ich::{StableHashingContext, StableHashingContextProvider, Fingerprint};
23 use super::debug::EdgeFilter;
24 use super::dep_node::{DepNode, DepKind, WorkProductId};
25 use super::query::DepGraphQuery;
26 use super::safe::DepGraphSafe;
27 use super::serialized::{SerializedDepGraph, SerializedDepNodeIndex};
28 use super::prev::PreviousDepGraph;
32 data: Option<Lrc<DepGraphData>>,
34 // A vector mapping depnodes from the current graph to their associated
35 // result value fingerprints. Do not rely on the length of this vector
36 // being the same as the number of nodes in the graph. The vector can
37 // contain an arbitrary number of zero-entries at the end.
38 fingerprints: Lrc<Lock<IndexVec<DepNodeIndex, Fingerprint>>>
42 newtype_index!(DepNodeIndex);
45 const INVALID: DepNodeIndex = DepNodeIndex(::std::u32::MAX);
48 #[derive(Copy, Clone, Debug, PartialEq, Eq, Hash)]
49 pub enum DepNodeColor {
55 pub fn is_green(self) -> bool {
57 DepNodeColor::Red => false,
58 DepNodeColor::Green(_) => true,
64 /// The new encoding of the dependency graph, optimized for red/green
65 /// tracking. The `current` field is the dependency graph of only the
66 /// current compilation session: We don't merge the previous dep-graph into
67 /// current one anymore.
68 current: Lock<CurrentDepGraph>,
70 /// The dep-graph from the previous compilation session. It contains all
71 /// nodes and edges as well as all fingerprints of nodes that have them.
72 previous: PreviousDepGraph,
74 colors: Lock<DepNodeColorMap>,
76 /// When we load, there may be `.o` files, cached mir, or other such
77 /// things available to us. If we find that they are not dirty, we
78 /// load the path to the file storing those work-products here into
79 /// this map. We can later look for and extract that data.
80 previous_work_products: RwLock<FxHashMap<WorkProductId, WorkProduct>>,
82 /// Work-products that we generate in this run.
83 work_products: RwLock<FxHashMap<WorkProductId, WorkProduct>>,
85 dep_node_debug: Lock<FxHashMap<DepNode, String>>,
87 // Used for testing, only populated when -Zquery-dep-graph is specified.
88 loaded_from_cache: Lock<FxHashMap<DepNodeIndex, bool>>,
93 pub fn new(prev_graph: PreviousDepGraph) -> DepGraph {
94 // Pre-allocate the fingerprints array. We over-allocate a little so
95 // that we hopefully don't have to re-allocate during this compilation
97 let prev_graph_node_count = prev_graph.node_count();
99 let fingerprints = IndexVec::from_elem_n(Fingerprint::ZERO,
100 (prev_graph_node_count * 115) / 100);
102 data: Some(Lrc::new(DepGraphData {
103 previous_work_products: RwLock::new(FxHashMap()),
104 work_products: RwLock::new(FxHashMap()),
105 dep_node_debug: Lock::new(FxHashMap()),
106 current: Lock::new(CurrentDepGraph::new()),
107 previous: prev_graph,
108 colors: Lock::new(DepNodeColorMap::new(prev_graph_node_count)),
109 loaded_from_cache: Lock::new(FxHashMap()),
111 fingerprints: Lrc::new(Lock::new(fingerprints)),
115 pub fn new_disabled() -> DepGraph {
118 fingerprints: Lrc::new(Lock::new(IndexVec::new())),
122 /// True if we are actually building the full dep-graph.
124 pub fn is_fully_enabled(&self) -> bool {
128 pub fn query(&self) -> DepGraphQuery {
129 let current_dep_graph = self.data.as_ref().unwrap().current.borrow();
130 let nodes: Vec<_> = current_dep_graph.nodes.iter().cloned().collect();
131 let mut edges = Vec::new();
132 for (index, edge_targets) in current_dep_graph.edges.iter_enumerated() {
133 let from = current_dep_graph.nodes[index];
134 for &edge_target in edge_targets {
135 let to = current_dep_graph.nodes[edge_target];
136 edges.push((from, to));
140 DepGraphQuery::new(&nodes[..], &edges[..])
143 pub fn assert_ignored(&self)
145 if let Some(..) = self.data {
146 ty::tls::with_context_opt(|icx| {
147 let icx = if let Some(icx) = icx { icx } else { return };
149 OpenTask::Ignore => {
152 _ => panic!("expected an ignore context")
158 pub fn with_ignore<OP,R>(&self, op: OP) -> R
159 where OP: FnOnce() -> R
161 ty::tls::with_context(|icx| {
162 let icx = ty::tls::ImplicitCtxt {
163 task: &OpenTask::Ignore,
167 ty::tls::enter_context(&icx, |_| {
173 /// Starts a new dep-graph task. Dep-graph tasks are specified
174 /// using a free function (`task`) and **not** a closure -- this
175 /// is intentional because we want to exercise tight control over
176 /// what state they have access to. In particular, we want to
177 /// prevent implicit 'leaks' of tracked state into the task (which
178 /// could then be read without generating correct edges in the
179 /// dep-graph -- see the [rustc guide] for more details on
180 /// the dep-graph). To this end, the task function gets exactly two
181 /// pieces of state: the context `cx` and an argument `arg`. Both
182 /// of these bits of state must be of some type that implements
183 /// `DepGraphSafe` and hence does not leak.
185 /// The choice of two arguments is not fundamental. One argument
186 /// would work just as well, since multiple values can be
187 /// collected using tuples. However, using two arguments works out
188 /// to be quite convenient, since it is common to need a context
189 /// (`cx`) and some argument (e.g., a `DefId` identifying what
190 /// item to process).
192 /// For cases where you need some other number of arguments:
194 /// - If you only need one argument, just use `()` for the `arg`
196 /// - If you need 3+ arguments, use a tuple for the
199 /// [rustc guide]: https://rust-lang-nursery.github.io/rustc-guide/incremental-compilation.html
200 pub fn with_task<'gcx, C, A, R>(&self,
206 where C: DepGraphSafe + StableHashingContextProvider<'gcx>,
207 R: HashStable<StableHashingContext<'gcx>>,
209 self.with_task_impl(key, cx, arg, false, task,
210 |key| OpenTask::Regular(Lock::new(RegularOpenTask {
213 read_set: FxHashSet(),
215 |data, key, task| data.borrow_mut().complete_task(key, task))
218 /// Creates a new dep-graph input with value `input`
219 pub fn input_task<'gcx, C, R>(&self,
224 where C: DepGraphSafe + StableHashingContextProvider<'gcx>,
225 R: HashStable<StableHashingContext<'gcx>>,
227 fn identity_fn<C, A>(_: C, arg: A) -> A {
231 self.with_task_impl(key, cx, input, true, identity_fn,
232 |_| OpenTask::Ignore,
233 |data, key, _| data.borrow_mut().alloc_node(key, Vec::new()))
236 fn with_task_impl<'gcx, C, A, R>(
243 create_task: fn(DepNode) -> OpenTask,
244 finish_task_and_alloc_depnode: fn(&Lock<CurrentDepGraph>,
246 OpenTask) -> DepNodeIndex
247 ) -> (R, DepNodeIndex)
249 C: DepGraphSafe + StableHashingContextProvider<'gcx>,
250 R: HashStable<StableHashingContext<'gcx>>,
252 if let Some(ref data) = self.data {
253 let open_task = create_task(key);
255 // In incremental mode, hash the result of the task. We don't
256 // do anything with the hash yet, but we are computing it
258 // - we make sure that the infrastructure works and
259 // - we can get an idea of the runtime cost.
260 let mut hcx = cx.get_stable_hashing_context();
262 if cfg!(debug_assertions) {
263 profq_msg(hcx.sess(), ProfileQueriesMsg::TaskBegin(key.clone()))
266 let result = if no_tcx {
269 ty::tls::with_context(|icx| {
270 let icx = ty::tls::ImplicitCtxt {
275 ty::tls::enter_context(&icx, |_| {
281 if cfg!(debug_assertions) {
282 profq_msg(hcx.sess(), ProfileQueriesMsg::TaskEnd)
285 let dep_node_index = finish_task_and_alloc_depnode(&data.current, key, open_task);
287 let mut stable_hasher = StableHasher::new();
288 result.hash_stable(&mut hcx, &mut stable_hasher);
290 let current_fingerprint = stable_hasher.finish();
292 // Store the current fingerprint
294 let mut fingerprints = self.fingerprints.borrow_mut();
296 if dep_node_index.index() >= fingerprints.len() {
297 fingerprints.resize(dep_node_index.index() + 1, Fingerprint::ZERO);
300 debug_assert!(fingerprints[dep_node_index] == Fingerprint::ZERO,
301 "DepGraph::with_task() - Duplicate fingerprint \
302 insertion for {:?}", key);
303 fingerprints[dep_node_index] = current_fingerprint;
306 // Determine the color of the new DepNode.
307 if let Some(prev_index) = data.previous.node_to_index_opt(&key) {
308 let prev_fingerprint = data.previous.fingerprint_by_index(prev_index);
310 let color = if current_fingerprint == prev_fingerprint {
311 DepNodeColor::Green(dep_node_index)
316 let mut colors = data.colors.borrow_mut();
317 debug_assert!(colors.get(prev_index).is_none(),
318 "DepGraph::with_task() - Duplicate DepNodeColor \
319 insertion for {:?}", key);
321 colors.insert(prev_index, color);
324 (result, dep_node_index)
326 if key.kind.fingerprint_needed_for_crate_hash() {
327 let mut hcx = cx.get_stable_hashing_context();
328 let result = task(cx, arg);
329 let mut stable_hasher = StableHasher::new();
330 result.hash_stable(&mut hcx, &mut stable_hasher);
331 let fingerprint = stable_hasher.finish();
333 let mut fingerprints = self.fingerprints.borrow_mut();
334 let dep_node_index = DepNodeIndex::new(fingerprints.len());
335 fingerprints.push(fingerprint);
337 debug_assert!(fingerprints[dep_node_index] == fingerprint,
338 "DepGraph::with_task() - Assigned fingerprint to \
339 unexpected index for {:?}", key);
341 (result, dep_node_index)
343 (task(cx, arg), DepNodeIndex::INVALID)
348 /// Execute something within an "anonymous" task, that is, a task the
349 /// DepNode of which is determined by the list of inputs it read from.
350 pub fn with_anon_task<OP,R>(&self, dep_kind: DepKind, op: OP) -> (R, DepNodeIndex)
351 where OP: FnOnce() -> R
353 if let Some(ref data) = self.data {
354 let (result, open_task) = ty::tls::with_context(|icx| {
355 let task = OpenTask::Anon(Lock::new(AnonOpenTask {
357 read_set: FxHashSet(),
361 let icx = ty::tls::ImplicitCtxt {
366 ty::tls::enter_context(&icx, |_| {
373 let dep_node_index = data.current
375 .pop_anon_task(dep_kind, open_task);
376 (result, dep_node_index)
378 (op(), DepNodeIndex::INVALID)
382 /// Execute something within an "eval-always" task which is a task
383 // that runs whenever anything changes.
384 pub fn with_eval_always_task<'gcx, C, A, R>(&self,
390 where C: DepGraphSafe + StableHashingContextProvider<'gcx>,
391 R: HashStable<StableHashingContext<'gcx>>,
393 self.with_task_impl(key, cx, arg, false, task,
394 |key| OpenTask::EvalAlways { node: key },
395 |data, key, task| data.borrow_mut().complete_eval_always_task(key, task))
399 pub fn read(&self, v: DepNode) {
400 if let Some(ref data) = self.data {
401 let mut current = data.current.borrow_mut();
402 if let Some(&dep_node_index) = current.node_to_node_index.get(&v) {
403 current.read_index(dep_node_index);
405 bug!("DepKind {:?} should be pre-allocated but isn't.", v.kind)
411 pub fn read_index(&self, dep_node_index: DepNodeIndex) {
412 if let Some(ref data) = self.data {
413 data.current.borrow_mut().read_index(dep_node_index);
418 pub fn dep_node_index_of(&self, dep_node: &DepNode) -> DepNodeIndex {
431 pub fn dep_node_exists(&self, dep_node: &DepNode) -> bool {
432 if let Some(ref data) = self.data {
433 data.current.borrow_mut().node_to_node_index.contains_key(dep_node)
440 pub fn fingerprint_of(&self, dep_node_index: DepNodeIndex) -> Fingerprint {
441 match self.fingerprints.borrow().get(dep_node_index) {
442 Some(&fingerprint) => fingerprint,
444 if let Some(ref data) = self.data {
445 let dep_node = data.current.borrow().nodes[dep_node_index];
446 bug!("Could not find current fingerprint for {:?}", dep_node)
448 bug!("Could not find current fingerprint for {:?}", dep_node_index)
454 pub fn prev_fingerprint_of(&self, dep_node: &DepNode) -> Option<Fingerprint> {
455 self.data.as_ref().unwrap().previous.fingerprint_of(dep_node)
459 pub fn prev_dep_node_index_of(&self, dep_node: &DepNode) -> SerializedDepNodeIndex {
460 self.data.as_ref().unwrap().previous.node_to_index(dep_node)
463 /// Indicates that a previous work product exists for `v`. This is
464 /// invoked during initial start-up based on what nodes are clean
465 /// (and what files exist in the incr. directory).
466 pub fn insert_previous_work_product(&self, v: &WorkProductId, data: WorkProduct) {
467 debug!("insert_previous_work_product({:?}, {:?})", v, data);
471 .previous_work_products
473 .insert(v.clone(), data);
476 /// Indicates that we created the given work-product in this run
477 /// for `v`. This record will be preserved and loaded in the next
479 pub fn insert_work_product(&self, v: &WorkProductId, data: WorkProduct) {
480 debug!("insert_work_product({:?}, {:?})", v, data);
486 .insert(v.clone(), data);
489 /// Check whether a previous work product exists for `v` and, if
490 /// so, return the path that leads to it. Used to skip doing work.
491 pub fn previous_work_product(&self, v: &WorkProductId) -> Option<WorkProduct> {
495 data.previous_work_products.borrow().get(v).cloned()
499 /// Access the map of work-products created during this run. Only
500 /// used during saving of the dep-graph.
501 pub fn work_products(&self) -> ReadGuard<FxHashMap<WorkProductId, WorkProduct>> {
502 self.data.as_ref().unwrap().work_products.borrow()
505 /// Access the map of work-products created during the cached run. Only
506 /// used during saving of the dep-graph.
507 pub fn previous_work_products(&self) -> ReadGuard<FxHashMap<WorkProductId, WorkProduct>> {
508 self.data.as_ref().unwrap().previous_work_products.borrow()
512 pub fn register_dep_node_debug_str<F>(&self,
515 where F: FnOnce() -> String
517 let dep_node_debug = &self.data.as_ref().unwrap().dep_node_debug;
519 if dep_node_debug.borrow().contains_key(&dep_node) {
522 let debug_str = debug_str_gen();
523 dep_node_debug.borrow_mut().insert(dep_node, debug_str);
526 pub(super) fn dep_node_debug_str(&self, dep_node: DepNode) -> Option<String> {
527 self.data.as_ref().and_then(|t| t.dep_node_debug.borrow().get(&dep_node).cloned())
530 pub fn edge_deduplication_data(&self) -> (u64, u64) {
531 let current_dep_graph = self.data.as_ref().unwrap().current.borrow();
533 (current_dep_graph.total_read_count, current_dep_graph.total_duplicate_read_count)
536 pub fn serialize(&self) -> SerializedDepGraph {
537 let mut fingerprints = self.fingerprints.borrow_mut();
538 let current_dep_graph = self.data.as_ref().unwrap().current.borrow();
540 // Make sure we don't run out of bounds below.
541 if current_dep_graph.nodes.len() > fingerprints.len() {
542 fingerprints.resize(current_dep_graph.nodes.len(), Fingerprint::ZERO);
545 let fingerprints = fingerprints.clone().convert_index_type();
546 let nodes = current_dep_graph.nodes.clone().convert_index_type();
548 let total_edge_count: usize = current_dep_graph.edges.iter()
552 let mut edge_list_indices = IndexVec::with_capacity(nodes.len());
553 let mut edge_list_data = Vec::with_capacity(total_edge_count);
555 for (current_dep_node_index, edges) in current_dep_graph.edges.iter_enumerated() {
556 let start = edge_list_data.len() as u32;
557 // This should really just be a memcpy :/
558 edge_list_data.extend(edges.iter().map(|i| SerializedDepNodeIndex::new(i.index())));
559 let end = edge_list_data.len() as u32;
561 debug_assert_eq!(current_dep_node_index.index(), edge_list_indices.len());
562 edge_list_indices.push((start, end));
565 debug_assert!(edge_list_data.len() <= ::std::u32::MAX as usize);
566 debug_assert_eq!(edge_list_data.len(), total_edge_count);
576 pub fn node_color(&self, dep_node: &DepNode) -> Option<DepNodeColor> {
577 if let Some(ref data) = self.data {
578 if let Some(prev_index) = data.previous.node_to_index_opt(dep_node) {
579 return data.colors.borrow().get(prev_index)
581 // This is a node that did not exist in the previous compilation
582 // session, so we consider it to be red.
583 return Some(DepNodeColor::Red)
590 pub fn try_mark_green<'tcx>(&self,
591 tcx: TyCtxt<'_, 'tcx, 'tcx>,
593 -> Option<DepNodeIndex> {
594 debug!("try_mark_green({:?}) - BEGIN", dep_node);
595 let data = self.data.as_ref().unwrap();
597 #[cfg(not(parallel_queries))]
598 debug_assert!(!data.current.borrow().node_to_node_index.contains_key(dep_node));
600 if dep_node.kind.is_input() {
601 // We should only hit try_mark_green() for inputs that do not exist
602 // anymore in the current compilation session. Existing inputs are
603 // eagerly marked as either red/green before any queries are
605 debug_assert!(dep_node.extract_def_id(tcx).is_none());
606 debug!("try_mark_green({:?}) - END - DepNode is deleted input", dep_node);
610 let (prev_deps, prev_dep_node_index) = match data.previous.edges_from(dep_node) {
612 // This DepNode and the corresponding query invocation existed
613 // in the previous compilation session too, so we can try to
614 // mark it as green by recursively marking all of its
615 // dependencies green.
619 // This DepNode did not exist in the previous compilation session,
620 // so we cannot mark it as green.
621 debug!("try_mark_green({:?}) - END - DepNode does not exist in \
622 current compilation session anymore", dep_node);
627 debug_assert!(data.colors.borrow().get(prev_dep_node_index).is_none());
629 let mut current_deps = Vec::new();
631 for &dep_dep_node_index in prev_deps {
632 let dep_dep_node_color = data.colors.borrow().get(dep_dep_node_index);
634 match dep_dep_node_color {
635 Some(DepNodeColor::Green(node_index)) => {
636 // This dependency has been marked as green before, we are
637 // still fine and can continue with checking the other
639 debug!("try_mark_green({:?}) --- found dependency {:?} to \
640 be immediately green",
642 data.previous.index_to_node(dep_dep_node_index));
643 current_deps.push(node_index);
645 Some(DepNodeColor::Red) => {
646 // We found a dependency the value of which has changed
647 // compared to the previous compilation session. We cannot
648 // mark the DepNode as green and also don't need to bother
649 // with checking any of the other dependencies.
650 debug!("try_mark_green({:?}) - END - dependency {:?} was \
653 data.previous.index_to_node(dep_dep_node_index));
657 let dep_dep_node = &data.previous.index_to_node(dep_dep_node_index);
659 // We don't know the state of this dependency. If it isn't
660 // an input node, let's try to mark it green recursively.
661 if !dep_dep_node.kind.is_input() {
662 debug!("try_mark_green({:?}) --- state of dependency {:?} \
663 is unknown, trying to mark it green", dep_node,
666 if let Some(node_index) = self.try_mark_green(tcx, dep_dep_node) {
667 debug!("try_mark_green({:?}) --- managed to MARK \
668 dependency {:?} as green", dep_node, dep_dep_node);
669 current_deps.push(node_index);
673 match dep_dep_node.kind {
676 DepKind::CrateMetadata => {
677 if dep_node.extract_def_id(tcx).is_none() {
678 // If the node does not exist anymore, we
679 // just fail to mark green.
682 // If the node does exist, it should have
683 // been pre-allocated.
684 bug!("DepNode {:?} should have been \
685 pre-allocated but wasn't.",
690 // For other kinds of inputs it's OK to be
696 // We failed to mark it green, so we try to force the query.
697 debug!("try_mark_green({:?}) --- trying to force \
698 dependency {:?}", dep_node, dep_dep_node);
699 if ::ty::maps::force_from_dep_node(tcx, dep_dep_node) {
700 let dep_dep_node_color = data.colors.borrow().get(dep_dep_node_index);
702 match dep_dep_node_color {
703 Some(DepNodeColor::Green(node_index)) => {
704 debug!("try_mark_green({:?}) --- managed to \
705 FORCE dependency {:?} to green",
706 dep_node, dep_dep_node);
707 current_deps.push(node_index);
709 Some(DepNodeColor::Red) => {
710 debug!("try_mark_green({:?}) - END - \
711 dependency {:?} was red after forcing",
717 if !tcx.sess.has_errors() {
718 bug!("try_mark_green() - Forcing the DepNode \
719 should have set its color")
721 // If the query we just forced has resulted
722 // in some kind of compilation error, we
723 // don't expect that the corresponding
724 // dep-node color has been updated.
729 // The DepNode could not be forced.
730 debug!("try_mark_green({:?}) - END - dependency {:?} \
731 could not be forced", dep_node, dep_dep_node);
738 // If we got here without hitting a `return` that means that all
739 // dependencies of this DepNode could be marked as green. Therefore we
740 // can also mark this DepNode as green.
742 // There may be multiple threads trying to mark the same dep node green concurrently
744 let (dep_node_index, did_allocation) = {
745 let mut current = data.current.borrow_mut();
747 if let Some(&dep_node_index) = current.node_to_node_index.get(&dep_node) {
748 // Someone else allocated it before us
749 (dep_node_index, false)
751 // We allocating an entry for the node in the current dependency graph and
752 // adding all the appropriate edges imported from the previous graph
753 (current.alloc_node(*dep_node, current_deps), true)
757 // ... copying the fingerprint from the previous graph too, so we don't
758 // have to recompute it ...
760 let fingerprint = data.previous.fingerprint_by_index(prev_dep_node_index);
761 let mut fingerprints = self.fingerprints.borrow_mut();
763 if dep_node_index.index() >= fingerprints.len() {
764 fingerprints.resize(dep_node_index.index() + 1, Fingerprint::ZERO);
767 // Multiple threads can all write the same fingerprint here
768 #[cfg(not(parallel_queries))]
769 debug_assert!(fingerprints[dep_node_index] == Fingerprint::ZERO,
770 "DepGraph::try_mark_green() - Duplicate fingerprint \
771 insertion for {:?}", dep_node);
773 fingerprints[dep_node_index] = fingerprint;
776 // ... emitting any stored diagnostic ...
778 // Only the thread which did the allocation emits the error messages
780 // FIXME: Ensure that these are printed before returning for all threads.
781 // Currently threads where did_allocation = false can continue on
782 // and emit other diagnostics before these diagnostics are emitted.
783 // Such diagnostics should be emitted after these.
784 // See https://github.com/rust-lang/rust/issues/48685
785 let diagnostics = tcx.on_disk_query_result_cache
786 .load_diagnostics(tcx, prev_dep_node_index);
788 if diagnostics.len() > 0 {
789 let handle = tcx.sess.diagnostic();
791 // Promote the previous diagnostics to the current session.
792 tcx.on_disk_query_result_cache
793 .store_diagnostics(dep_node_index, diagnostics.clone());
795 for diagnostic in diagnostics {
796 DiagnosticBuilder::new_diagnostic(handle, diagnostic).emit();
801 // ... and finally storing a "Green" entry in the color map.
802 let mut colors = data.colors.borrow_mut();
803 // Multiple threads can all write the same color here
804 #[cfg(not(parallel_queries))]
805 debug_assert!(colors.get(prev_dep_node_index).is_none(),
806 "DepGraph::try_mark_green() - Duplicate DepNodeColor \
807 insertion for {:?}", dep_node);
809 colors.insert(prev_dep_node_index, DepNodeColor::Green(dep_node_index));
811 debug!("try_mark_green({:?}) - END - successfully marked as green", dep_node);
815 // Returns true if the given node has been marked as green during the
816 // current compilation session. Used in various assertions
817 pub fn is_green(&self, dep_node: &DepNode) -> bool {
818 self.node_color(dep_node).map(|c| c.is_green()).unwrap_or(false)
821 // This method loads all on-disk cacheable query results into memory, so
822 // they can be written out to the new cache file again. Most query results
823 // will already be in memory but in the case where we marked something as
824 // green but then did not need the value, that value will never have been
827 // This method will only load queries that will end up in the disk cache.
828 // Other queries will not be executed.
829 pub fn exec_cache_promotions<'a, 'tcx>(&self, tcx: TyCtxt<'a, 'tcx, 'tcx>) {
830 let green_nodes: Vec<DepNode> = {
831 let data = self.data.as_ref().unwrap();
832 let colors = data.colors.borrow();
833 colors.values.indices().filter_map(|prev_index| {
834 match colors.get(prev_index) {
835 Some(DepNodeColor::Green(_)) => {
836 let dep_node = data.previous.index_to_node(prev_index);
837 if dep_node.cache_on_disk(tcx) {
844 Some(DepNodeColor::Red) => {
845 // We can skip red nodes because a node can only be marked
846 // as red if the query result was recomputed and thus is
847 // already in memory.
854 for dep_node in green_nodes {
855 dep_node.load_from_on_disk_cache(tcx);
859 pub fn mark_loaded_from_cache(&self, dep_node_index: DepNodeIndex, state: bool) {
860 debug!("mark_loaded_from_cache({:?}, {})",
861 self.data.as_ref().unwrap().current.borrow().nodes[dep_node_index],
869 .insert(dep_node_index, state);
872 pub fn was_loaded_from_cache(&self, dep_node: &DepNode) -> Option<bool> {
873 let data = self.data.as_ref().unwrap();
874 let dep_node_index = data.current.borrow().node_to_node_index[dep_node];
875 data.loaded_from_cache.borrow().get(&dep_node_index).cloned()
879 /// A "work product" is an intermediate result that we save into the
880 /// incremental directory for later re-use. The primary example are
881 /// the object files that we save for each partition at code
884 /// Each work product is associated with a dep-node, representing the
885 /// process that produced the work-product. If that dep-node is found
886 /// to be dirty when we load up, then we will delete the work-product
887 /// at load time. If the work-product is found to be clean, then we
888 /// will keep a record in the `previous_work_products` list.
890 /// In addition, work products have an associated hash. This hash is
891 /// an extra hash that can be used to decide if the work-product from
892 /// a previous compilation can be re-used (in addition to the dirty
895 /// As the primary example, consider the object files we generate for
896 /// each partition. In the first run, we create partitions based on
897 /// the symbols that need to be compiled. For each partition P, we
898 /// hash the symbols in P and create a `WorkProduct` record associated
899 /// with `DepNode::TransPartition(P)`; the hash is the set of symbols
902 /// The next time we compile, if the `DepNode::TransPartition(P)` is
903 /// judged to be clean (which means none of the things we read to
904 /// generate the partition were found to be dirty), it will be loaded
905 /// into previous work products. We will then regenerate the set of
906 /// symbols in the partition P and hash them (note that new symbols
907 /// may be added -- for example, new monomorphizations -- even if
908 /// nothing in P changed!). We will compare that hash against the
909 /// previous hash. If it matches up, we can reuse the object file.
910 #[derive(Clone, Debug, RustcEncodable, RustcDecodable)]
911 pub struct WorkProduct {
912 pub cgu_name: String,
913 /// Saved files associated with this CGU
914 pub saved_files: Vec<(WorkProductFileKind, String)>,
917 #[derive(Clone, Copy, Debug, RustcEncodable, RustcDecodable)]
918 pub enum WorkProductFileKind {
924 pub(super) struct CurrentDepGraph {
925 nodes: IndexVec<DepNodeIndex, DepNode>,
926 edges: IndexVec<DepNodeIndex, Vec<DepNodeIndex>>,
927 node_to_node_index: FxHashMap<DepNode, DepNodeIndex>,
928 forbidden_edge: Option<EdgeFilter>,
930 // Anonymous DepNodes are nodes the ID of which we compute from the list of
931 // their edges. This has the beneficial side-effect that multiple anonymous
932 // nodes can be coalesced into one without changing the semantics of the
933 // dependency graph. However, the merging of nodes can lead to a subtle
934 // problem during red-green marking: The color of an anonymous node from
935 // the current session might "shadow" the color of the node with the same
936 // ID from the previous session. In order to side-step this problem, we make
937 // sure that anon-node IDs allocated in different sessions don't overlap.
938 // This is implemented by mixing a session-key into the ID fingerprint of
939 // each anon node. The session-key is just a random number generated when
940 // the DepGraph is created.
941 anon_id_seed: Fingerprint,
943 total_read_count: u64,
944 total_duplicate_read_count: u64,
947 impl CurrentDepGraph {
948 fn new() -> CurrentDepGraph {
949 use std::time::{SystemTime, UNIX_EPOCH};
951 let duration = SystemTime::now().duration_since(UNIX_EPOCH).unwrap();
952 let nanos = duration.as_secs() * 1_000_000_000 +
953 duration.subsec_nanos() as u64;
954 let mut stable_hasher = StableHasher::new();
955 nanos.hash(&mut stable_hasher);
957 let forbidden_edge = if cfg!(debug_assertions) {
958 match env::var("RUST_FORBID_DEP_GRAPH_EDGE") {
960 match EdgeFilter::new(&s) {
962 Err(err) => bug!("RUST_FORBID_DEP_GRAPH_EDGE invalid: {}", err),
972 nodes: IndexVec::new(),
973 edges: IndexVec::new(),
974 node_to_node_index: FxHashMap(),
975 anon_id_seed: stable_hasher.finish(),
978 total_duplicate_read_count: 0,
982 fn complete_task(&mut self, key: DepNode, task: OpenTask) -> DepNodeIndex {
983 if let OpenTask::Regular(task) = task {
984 let RegularOpenTask {
988 } = task.into_inner();
989 assert_eq!(node, key);
991 // If this is an input node, we expect that it either has no
992 // dependencies, or that it just depends on DepKind::CrateMetadata
993 // or DepKind::Krate. This happens for some "thin wrapper queries"
994 // like `crate_disambiguator` which sometimes have zero deps (for
995 // when called for LOCAL_CRATE) or they depend on a CrateMetadata
997 if cfg!(debug_assertions) {
998 if node.kind.is_input() && reads.len() > 0 &&
999 // FIXME(mw): Special case for DefSpan until Spans are handled
1000 // better in general.
1001 node.kind != DepKind::DefSpan &&
1002 reads.iter().any(|&i| {
1003 !(self.nodes[i].kind == DepKind::CrateMetadata ||
1004 self.nodes[i].kind == DepKind::Krate)
1007 bug!("Input node {:?} with unexpected reads: {:?}",
1009 reads.iter().map(|&i| self.nodes[i]).collect::<Vec<_>>())
1013 self.alloc_node(node, reads)
1015 bug!("complete_task() - Expected regular task to be popped")
1019 fn pop_anon_task(&mut self, kind: DepKind, task: OpenTask) -> DepNodeIndex {
1020 if let OpenTask::Anon(task) = task {
1024 } = task.into_inner();
1025 debug_assert!(!kind.is_input());
1027 let mut fingerprint = self.anon_id_seed;
1028 let mut hasher = StableHasher::new();
1030 for &read in reads.iter() {
1031 let read_dep_node = self.nodes[read];
1033 ::std::mem::discriminant(&read_dep_node.kind).hash(&mut hasher);
1035 // Fingerprint::combine() is faster than sending Fingerprint
1036 // through the StableHasher (at least as long as StableHasher
1038 fingerprint = fingerprint.combine(read_dep_node.hash);
1041 fingerprint = fingerprint.combine(hasher.finish());
1043 let target_dep_node = DepNode {
1048 if let Some(&index) = self.node_to_node_index.get(&target_dep_node) {
1051 self.alloc_node(target_dep_node, reads)
1054 bug!("pop_anon_task() - Expected anonymous task to be popped")
1058 fn complete_eval_always_task(&mut self, key: DepNode, task: OpenTask) -> DepNodeIndex {
1059 if let OpenTask::EvalAlways {
1062 debug_assert_eq!(node, key);
1063 let krate_idx = self.node_to_node_index[&DepNode::new_no_params(DepKind::Krate)];
1064 self.alloc_node(node, vec![krate_idx])
1066 bug!("complete_eval_always_task() - Expected eval always task to be popped");
1070 fn read_index(&mut self, source: DepNodeIndex) {
1071 ty::tls::with_context_opt(|icx| {
1072 let icx = if let Some(icx) = icx { icx } else { return };
1074 OpenTask::Regular(ref task) => {
1075 let mut task = task.lock();
1076 self.total_read_count += 1;
1077 if task.read_set.insert(source) {
1078 task.reads.push(source);
1080 if cfg!(debug_assertions) {
1081 if let Some(ref forbidden_edge) = self.forbidden_edge {
1082 let target = &task.node;
1083 let source = self.nodes[source];
1084 if forbidden_edge.test(&source, &target) {
1085 bug!("forbidden edge {:?} -> {:?} created",
1092 self.total_duplicate_read_count += 1;
1095 OpenTask::Anon(ref task) => {
1096 let mut task = task.lock();
1097 if task.read_set.insert(source) {
1098 task.reads.push(source);
1101 OpenTask::Ignore | OpenTask::EvalAlways { .. } => {
1108 fn alloc_node(&mut self,
1110 edges: Vec<DepNodeIndex>)
1112 debug_assert_eq!(self.edges.len(), self.nodes.len());
1113 debug_assert_eq!(self.node_to_node_index.len(), self.nodes.len());
1114 debug_assert!(!self.node_to_node_index.contains_key(&dep_node));
1115 let dep_node_index = DepNodeIndex::new(self.nodes.len());
1116 self.nodes.push(dep_node);
1117 self.node_to_node_index.insert(dep_node, dep_node_index);
1118 self.edges.push(edges);
1123 pub struct RegularOpenTask {
1125 reads: Vec<DepNodeIndex>,
1126 read_set: FxHashSet<DepNodeIndex>,
1129 pub struct AnonOpenTask {
1130 reads: Vec<DepNodeIndex>,
1131 read_set: FxHashSet<DepNodeIndex>,
1135 Regular(Lock<RegularOpenTask>),
1136 Anon(Lock<AnonOpenTask>),
1143 // A data structure that stores Option<DepNodeColor> values as a contiguous
1144 // array, using one u32 per entry.
1145 struct DepNodeColorMap {
1146 values: IndexVec<SerializedDepNodeIndex, u32>,
1149 const COMPRESSED_NONE: u32 = 0;
1150 const COMPRESSED_RED: u32 = 1;
1151 const COMPRESSED_FIRST_GREEN: u32 = 2;
1153 impl DepNodeColorMap {
1154 fn new(size: usize) -> DepNodeColorMap {
1156 values: IndexVec::from_elem_n(COMPRESSED_NONE, size)
1160 fn get(&self, index: SerializedDepNodeIndex) -> Option<DepNodeColor> {
1161 match self.values[index] {
1162 COMPRESSED_NONE => None,
1163 COMPRESSED_RED => Some(DepNodeColor::Red),
1164 value => Some(DepNodeColor::Green(DepNodeIndex(value - COMPRESSED_FIRST_GREEN)))
1168 fn insert(&mut self, index: SerializedDepNodeIndex, color: DepNodeColor) {
1169 self.values[index] = match color {
1170 DepNodeColor::Red => COMPRESSED_RED,
1171 DepNodeColor::Green(index) => index.0 + COMPRESSED_FIRST_GREEN,