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 hir::def_id::DefId;
12 use rustc_data_structures::fx::FxHashMap;
13 use session::config::OutputType;
14 use std::cell::{Ref, RefCell};
18 use super::dep_node::{DepNode, WorkProductId};
19 use super::query::DepGraphQuery;
21 use super::thread::{DepGraphThreadData, DepMessage};
25 data: Rc<DepGraphData>
29 /// We send messages to the thread to let it build up the dep-graph
30 /// from the current run.
31 thread: DepGraphThreadData,
33 /// When we load, there may be `.o` files, cached mir, or other such
34 /// things available to us. If we find that they are not dirty, we
35 /// load the path to the file storing those work-products here into
36 /// this map. We can later look for and extract that data.
37 previous_work_products: RefCell<FxHashMap<Arc<WorkProductId>, WorkProduct>>,
39 /// Work-products that we generate in this run.
40 work_products: RefCell<FxHashMap<Arc<WorkProductId>, WorkProduct>>,
44 pub fn new(enabled: bool) -> DepGraph {
46 data: Rc::new(DepGraphData {
47 thread: DepGraphThreadData::new(enabled),
48 previous_work_products: RefCell::new(FxHashMap()),
49 work_products: RefCell::new(FxHashMap()),
54 /// True if we are actually building the full dep-graph.
56 pub fn is_fully_enabled(&self) -> bool {
57 self.data.thread.is_fully_enabled()
60 pub fn query(&self) -> DepGraphQuery<DefId> {
61 self.data.thread.query()
64 pub fn in_ignore<'graph>(&'graph self) -> Option<raii::IgnoreTask<'graph>> {
65 raii::IgnoreTask::new(&self.data.thread)
68 pub fn in_task<'graph>(&'graph self, key: DepNode<DefId>) -> Option<raii::DepTask<'graph>> {
69 raii::DepTask::new(&self.data.thread, key)
72 pub fn with_ignore<OP,R>(&self, op: OP) -> R
73 where OP: FnOnce() -> R
75 let _task = self.in_ignore();
79 pub fn with_task<OP,R>(&self, key: DepNode<DefId>, op: OP) -> R
80 where OP: FnOnce() -> R
82 let _task = self.in_task(key);
86 pub fn read(&self, v: DepNode<DefId>) {
87 if self.data.thread.is_enqueue_enabled() {
88 self.data.thread.enqueue(DepMessage::Read(v));
92 pub fn write(&self, v: DepNode<DefId>) {
93 if self.data.thread.is_enqueue_enabled() {
94 self.data.thread.enqueue(DepMessage::Write(v));
98 /// Indicates that a previous work product exists for `v`. This is
99 /// invoked during initial start-up based on what nodes are clean
100 /// (and what files exist in the incr. directory).
101 pub fn insert_previous_work_product(&self, v: &Arc<WorkProductId>, data: WorkProduct) {
102 debug!("insert_previous_work_product({:?}, {:?})", v, data);
103 self.data.previous_work_products.borrow_mut()
104 .insert(v.clone(), data);
107 /// Indicates that we created the given work-product in this run
108 /// for `v`. This record will be preserved and loaded in the next
110 pub fn insert_work_product(&self, v: &Arc<WorkProductId>, data: WorkProduct) {
111 debug!("insert_work_product({:?}, {:?})", v, data);
112 self.data.work_products.borrow_mut()
113 .insert(v.clone(), data);
116 /// Check whether a previous work product exists for `v` and, if
117 /// so, return the path that leads to it. Used to skip doing work.
118 pub fn previous_work_product(&self, v: &Arc<WorkProductId>) -> Option<WorkProduct> {
119 self.data.previous_work_products.borrow()
124 /// Access the map of work-products created during this run. Only
125 /// used during saving of the dep-graph.
126 pub fn work_products(&self) -> Ref<FxHashMap<Arc<WorkProductId>, WorkProduct>> {
127 self.data.work_products.borrow()
131 /// A "work product" is an intermediate result that we save into the
132 /// incremental directory for later re-use. The primary example are
133 /// the object files that we save for each partition at code
136 /// Each work product is associated with a dep-node, representing the
137 /// process that produced the work-product. If that dep-node is found
138 /// to be dirty when we load up, then we will delete the work-product
139 /// at load time. If the work-product is found to be clean, then we
140 /// will keep a record in the `previous_work_products` list.
142 /// In addition, work products have an associated hash. This hash is
143 /// an extra hash that can be used to decide if the work-product from
144 /// a previous compilation can be re-used (in addition to the dirty
147 /// As the primary example, consider the object files we generate for
148 /// each partition. In the first run, we create partitions based on
149 /// the symbols that need to be compiled. For each partition P, we
150 /// hash the symbols in P and create a `WorkProduct` record associated
151 /// with `DepNode::TransPartition(P)`; the hash is the set of symbols
154 /// The next time we compile, if the `DepNode::TransPartition(P)` is
155 /// judged to be clean (which means none of the things we read to
156 /// generate the partition were found to be dirty), it will be loaded
157 /// into previous work products. We will then regenerate the set of
158 /// symbols in the partition P and hash them (note that new symbols
159 /// may be added -- for example, new monomorphizations -- even if
160 /// nothing in P changed!). We will compare that hash against the
161 /// previous hash. If it matches up, we can reuse the object file.
162 #[derive(Clone, Debug, RustcEncodable, RustcDecodable)]
163 pub struct WorkProduct {
164 /// Extra hash used to decide if work-product is still suitable;
165 /// note that this is *not* a hash of the work-product itself.
166 /// See documentation on `WorkProduct` type for an example.
169 /// Saved files associated with this CGU
170 pub saved_files: Vec<(OutputType, String)>,