| // Copyright 2014 The Rust Project Developers. See the COPYRIGHT |
| // file at the top-level directory of this distribution and at |
| // http://rust-lang.org/COPYRIGHT. |
| // |
| // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or |
| // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license |
| // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your |
| // option. This file may not be copied, modified, or distributed |
| // except according to those terms. |
| |
| use hir::def_id::DefId; |
| use rustc_data_structures::fnv::FnvHashMap; |
| use session::config::OutputType; |
| use std::cell::{Ref, RefCell}; |
| use std::rc::Rc; |
| use std::sync::Arc; |
| |
| use super::dep_node::{DepNode, WorkProductId}; |
| use super::query::DepGraphQuery; |
| use super::raii; |
| use super::thread::{DepGraphThreadData, DepMessage}; |
| |
| #[derive(Clone)] |
| pub struct DepGraph { |
| data: Rc<DepGraphData> |
| } |
| |
| struct DepGraphData { |
| /// We send messages to the thread to let it build up the dep-graph |
| /// from the current run. |
| thread: DepGraphThreadData, |
| |
| /// When we load, there may be `.o` files, cached mir, or other such |
| /// things available to us. If we find that they are not dirty, we |
| /// load the path to the file storing those work-products here into |
| /// this map. We can later look for and extract that data. |
| previous_work_products: RefCell<FnvHashMap<Arc<WorkProductId>, WorkProduct>>, |
| |
| /// Work-products that we generate in this run. |
| work_products: RefCell<FnvHashMap<Arc<WorkProductId>, WorkProduct>>, |
| } |
| |
| impl DepGraph { |
| pub fn new(enabled: bool) -> DepGraph { |
| DepGraph { |
| data: Rc::new(DepGraphData { |
| thread: DepGraphThreadData::new(enabled), |
| previous_work_products: RefCell::new(FnvHashMap()), |
| work_products: RefCell::new(FnvHashMap()) |
| }) |
| } |
| } |
| |
| /// True if we are actually building a dep-graph. If this returns false, |
| /// then the other methods on this `DepGraph` will have no net effect. |
| #[inline] |
| pub fn enabled(&self) -> bool { |
| self.data.thread.enabled() |
| } |
| |
| pub fn query(&self) -> DepGraphQuery<DefId> { |
| self.data.thread.query() |
| } |
| |
| pub fn in_ignore<'graph>(&'graph self) -> raii::IgnoreTask<'graph> { |
| raii::IgnoreTask::new(&self.data.thread) |
| } |
| |
| pub fn in_task<'graph>(&'graph self, key: DepNode<DefId>) -> raii::DepTask<'graph> { |
| raii::DepTask::new(&self.data.thread, key) |
| } |
| |
| pub fn with_ignore<OP,R>(&self, op: OP) -> R |
| where OP: FnOnce() -> R |
| { |
| let _task = self.in_ignore(); |
| op() |
| } |
| |
| pub fn with_task<OP,R>(&self, key: DepNode<DefId>, op: OP) -> R |
| where OP: FnOnce() -> R |
| { |
| let _task = self.in_task(key); |
| op() |
| } |
| |
| pub fn read(&self, v: DepNode<DefId>) { |
| self.data.thread.enqueue(DepMessage::Read(v)); |
| } |
| |
| pub fn write(&self, v: DepNode<DefId>) { |
| self.data.thread.enqueue(DepMessage::Write(v)); |
| } |
| |
| /// Indicates that a previous work product exists for `v`. This is |
| /// invoked during initial start-up based on what nodes are clean |
| /// (and what files exist in the incr. directory). |
| pub fn insert_previous_work_product(&self, v: &Arc<WorkProductId>, data: WorkProduct) { |
| debug!("insert_previous_work_product({:?}, {:?})", v, data); |
| self.data.previous_work_products.borrow_mut() |
| .insert(v.clone(), data); |
| } |
| |
| /// Indicates that we created the given work-product in this run |
| /// for `v`. This record will be preserved and loaded in the next |
| /// run. |
| pub fn insert_work_product(&self, v: &Arc<WorkProductId>, data: WorkProduct) { |
| debug!("insert_work_product({:?}, {:?})", v, data); |
| self.data.work_products.borrow_mut() |
| .insert(v.clone(), data); |
| } |
| |
| /// Check whether a previous work product exists for `v` and, if |
| /// so, return the path that leads to it. Used to skip doing work. |
| pub fn previous_work_product(&self, v: &Arc<WorkProductId>) -> Option<WorkProduct> { |
| self.data.previous_work_products.borrow() |
| .get(v) |
| .cloned() |
| } |
| |
| /// Access the map of work-products created during this run. Only |
| /// used during saving of the dep-graph. |
| pub fn work_products(&self) -> Ref<FnvHashMap<Arc<WorkProductId>, WorkProduct>> { |
| self.data.work_products.borrow() |
| } |
| } |
| |
| /// A "work product" is an intermediate result that we save into the |
| /// incremental directory for later re-use. The primary example are |
| /// the object files that we save for each partition at code |
| /// generation time. |
| /// |
| /// Each work product is associated with a dep-node, representing the |
| /// process that produced the work-product. If that dep-node is found |
| /// to be dirty when we load up, then we will delete the work-product |
| /// at load time. If the work-product is found to be clean, then we |
| /// will keep a record in the `previous_work_products` list. |
| /// |
| /// In addition, work products have an associated hash. This hash is |
| /// an extra hash that can be used to decide if the work-product from |
| /// a previous compilation can be re-used (in addition to the dirty |
| /// edges check). |
| /// |
| /// As the primary example, consider the object files we generate for |
| /// each partition. In the first run, we create partitions based on |
| /// the symbols that need to be compiled. For each partition P, we |
| /// hash the symbols in P and create a `WorkProduct` record associated |
| /// with `DepNode::TransPartition(P)`; the hash is the set of symbols |
| /// in P. |
| /// |
| /// The next time we compile, if the `DepNode::TransPartition(P)` is |
| /// judged to be clean (which means none of the things we read to |
| /// generate the partition were found to be dirty), it will be loaded |
| /// into previous work products. We will then regenerate the set of |
| /// symbols in the partition P and hash them (note that new symbols |
| /// may be added -- for example, new monomorphizations -- even if |
| /// nothing in P changed!). We will compare that hash against the |
| /// previous hash. If it matches up, we can reuse the object file. |
| #[derive(Clone, Debug, RustcEncodable, RustcDecodable)] |
| pub struct WorkProduct { |
| /// Extra hash used to decide if work-product is still suitable; |
| /// note that this is *not* a hash of the work-product itself. |
| /// See documentation on `WorkProduct` type for an example. |
| pub input_hash: u64, |
| |
| /// Saved files associated with this CGU |
| pub saved_files: Vec<(OutputType, String)>, |
| } |