incr.comp.: Remove IncrementalHashesMap and calculate_svh module.

11 files changed, 52 insertions, 394 deletions

diff --git a/src/librustc_driver/driver.rs b/src/librustc_driver/driver.rs
index 7d06d02de63..ce4ab2c8a1d 100644
--- a/src/librustc_driver/driver.rs
+++ b/src/librustc_driver/driver.rs
@@ -30,7 +30,7 @@ use rustc::traits;
 use rustc::util::common::{ErrorReported, time};
 use rustc_allocator as allocator;
 use rustc_borrowck as borrowck;
-use rustc_incremental::{self, IncrementalHashesMap};
+use rustc_incremental;
 use rustc_resolve::{MakeGlobMap, Resolver};
 use rustc_metadata::creader::CrateLoader;
 use rustc_metadata::cstore::{self, CStore};
@@ -218,7 +218,7 @@ pub fn compile_input(sess: &Session,
                                     &arenas,
                                     &crate_name,
                                     &outputs,
-                                    |tcx, analysis, incremental_hashes_map, rx, result| {
+                                    |tcx, analysis, rx, result| {
             {
                 // Eventually, we will want to track plugins.
                 let _ignore = tcx.dep_graph.in_ignore();
@@ -246,9 +246,7 @@ pub fn compile_input(sess: &Session,
                 tcx.print_debug_stats();
             }
 
-            let trans = phase_4_translate_to_llvm(tcx,
-                                                  incremental_hashes_map,
-                                                  rx);
+            let trans = phase_4_translate_to_llvm(tcx, rx);
 
             if log_enabled!(::log::LogLevel::Info) {
                 println!("Post-trans");
@@ -921,7 +919,6 @@ pub fn phase_3_run_analysis_passes<'tcx, F, R>(sess: &'tcx Session,
                                                -> Result<R, CompileIncomplete>
     where F: for<'a> FnOnce(TyCtxt<'a, 'tcx, 'tcx>,
                             ty::CrateAnalysis,
-                            IncrementalHashesMap,
                             mpsc::Receiver<Box<Any + Send>>,
                             CompileResult) -> R
 {
@@ -1053,22 +1050,16 @@ pub fn phase_3_run_analysis_passes<'tcx, F, R>(sess: &'tcx Session,
                              tx,
                              output_filenames,
                              |tcx| {
-        let incremental_hashes_map =
-            time(time_passes,
-                 "compute_incremental_hashes_map",
-                 || rustc_incremental::compute_incremental_hashes_map(tcx));
-
         time(time_passes,
              "load_dep_graph",
-             || rustc_incremental::load_dep_graph(tcx, &incremental_hashes_map));
+             || rustc_incremental::load_dep_graph(tcx));
 
         time(time_passes,
              "stability checking",
              || stability::check_unstable_api_usage(tcx));
 
         // passes are timed inside typeck
-        try_with_f!(typeck::check_crate(tcx),
-                    (tcx, analysis, incremental_hashes_map, rx));
+        try_with_f!(typeck::check_crate(tcx), (tcx, analysis, rx));
 
         time(time_passes,
              "const checking",
@@ -1112,7 +1103,7 @@ pub fn phase_3_run_analysis_passes<'tcx, F, R>(sess: &'tcx Session,
         // lint warnings and so on -- kindck used to do this abort, but
         // kindck is gone now). -nmatsakis
         if sess.err_count() > 0 {
-            return Ok(f(tcx, analysis, incremental_hashes_map, rx, sess.compile_status()));
+            return Ok(f(tcx, analysis, rx, sess.compile_status()));
         }
 
         time(time_passes, "death checking", || middle::dead::check_crate(tcx));
@@ -1123,14 +1114,13 @@ pub fn phase_3_run_analysis_passes<'tcx, F, R>(sess: &'tcx Session,
 
         time(time_passes, "lint checking", || lint::check_crate(tcx));
 
-        return Ok(f(tcx, analysis, incremental_hashes_map, rx, tcx.sess.compile_status()));
+        return Ok(f(tcx, analysis, rx, tcx.sess.compile_status()));
     })
 }
 
 /// Run the translation phase to LLVM, after which the AST and analysis can
 /// be discarded.
 pub fn phase_4_translate_to_llvm<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
-                                           incremental_hashes_map: IncrementalHashesMap,
                                            rx: mpsc::Receiver<Box<Any + Send>>)
                                            -> write::OngoingCrateTranslation {
     let time_passes = tcx.sess.time_passes();
@@ -1141,7 +1131,7 @@ pub fn phase_4_translate_to_llvm<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
 
     let translation =
         time(time_passes, "translation", move || {
-            trans::trans_crate(tcx, incremental_hashes_map, rx)
+            trans::trans_crate(tcx, rx)
         });
 
     if tcx.sess.profile_queries() {
diff --git a/src/librustc_driver/pretty.rs b/src/librustc_driver/pretty.rs
index cd153b82077..b633a170422 100644
--- a/src/librustc_driver/pretty.rs
+++ b/src/librustc_driver/pretty.rs
@@ -237,7 +237,7 @@ impl PpSourceMode {
                                                                  arenas,
                                                                  id,
                                                                  output_filenames,
-                                                                 |tcx, _, _, _, _| {
+                                                                 |tcx, _, _, _| {
                     let empty_tables = ty::TypeckTables::empty(None);
                     let annotation = TypedAnnotation {
                         tcx,
@@ -1036,7 +1036,7 @@ fn print_with_analysis<'tcx, 'a: 'tcx>(sess: &'a Session,
                                                      arenas,
                                                      crate_name,
                                                      output_filenames,
-                                                     |tcx, _, _, _, _| {
+                                                     |tcx, _, _, _| {
         match ppm {
             PpmMir | PpmMirCFG => {
                 if let Some(nodeid) = nodeid {
diff --git a/src/librustc_incremental/calculate_svh/mod.rs b/src/librustc_incremental/calculate_svh/mod.rs
deleted file mode 100644
index 0329aa8d674..00000000000
--- a/src/librustc_incremental/calculate_svh/mod.rs
+++ /dev/null
@@ -1,331 +0,0 @@
-// Copyright 2012-2014 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.
-
-//! Calculation of the (misnamed) "strict version hash" for crates and
-//! items. This hash is used to tell when the HIR changed in such a
-//! way that results from previous compilations may no longer be
-//! applicable and hence must be recomputed. It should probably be
-//! renamed to the ICH (incremental compilation hash).
-//!
-//! The hashes for all items are computed once at the beginning of
-//! compilation and stored into a map. In addition, a hash is computed
-//! of the **entire crate**.
-//!
-//! Storing the hashes in a map avoids the need to compute them twice
-//! (once when loading prior incremental results and once when
-//! saving), but it is also important for correctness: at least as of
-//! the time of this writing, the typeck passes rewrites entries in
-//! the dep-map in-place to accommodate UFCS resolutions. Since name
-//! resolution is part of the hash, the result is that hashes computed
-//! at the end of compilation would be different from those computed
-//! at the beginning.
-
-use std::cell::RefCell;
-use std::hash::Hash;
-use rustc::dep_graph::{DepNode, DepKind};
-use rustc::hir;
-use rustc::hir::def_id::{CRATE_DEF_INDEX, DefId, DefIndex};
-use rustc::hir::map::DefPathHash;
-use rustc::hir::itemlikevisit::ItemLikeVisitor;
-use rustc::ich::{Fingerprint, StableHashingContext};
-use rustc::ty::TyCtxt;
-use rustc::util::common::record_time;
-use rustc_data_structures::stable_hasher::{StableHasher, HashStable};
-use rustc_data_structures::fx::FxHashMap;
-use rustc_data_structures::accumulate_vec::AccumulateVec;
-
-pub type IchHasher = StableHasher<Fingerprint>;
-
-pub struct IncrementalHashesMap {
-    hashes: FxHashMap<DepNode, Fingerprint>,
-
-    // These are the metadata hashes for the current crate as they were stored
-    // during the last compilation session. They are only loaded if
-    // -Z query-dep-graph was specified and are needed for auto-tests using
-    // the #[rustc_metadata_dirty] and #[rustc_metadata_clean] attributes to
-    // check whether some metadata hash has changed in between two revisions.
-    pub prev_metadata_hashes: RefCell<FxHashMap<DefId, Fingerprint>>,
-}
-
-impl IncrementalHashesMap {
-    pub fn new() -> IncrementalHashesMap {
-        IncrementalHashesMap {
-            hashes: FxHashMap(),
-            prev_metadata_hashes: RefCell::new(FxHashMap()),
-        }
-    }
-
-    pub fn insert(&mut self, k: DepNode, v: Fingerprint) {
-        assert!(self.hashes.insert(k, v).is_none());
-    }
-
-    pub fn iter<'a>(&'a self)
-                    -> ::std::collections::hash_map::Iter<'a, DepNode, Fingerprint> {
-        self.hashes.iter()
-    }
-
-    pub fn len(&self) -> usize {
-        self.hashes.len()
-    }
-}
-
-impl<'a> ::std::ops::Index<&'a DepNode> for IncrementalHashesMap {
-    type Output = Fingerprint;
-
-    fn index(&self, index: &'a DepNode) -> &Fingerprint {
-        match self.hashes.get(index) {
-            Some(fingerprint) => fingerprint,
-            None => {
-                bug!("Could not find ICH for {:?}", index);
-            }
-        }
-    }
-}
-
-struct ComputeItemHashesVisitor<'a, 'tcx: 'a> {
-    tcx: TyCtxt<'a, 'tcx, 'tcx>,
-    hcx: StableHashingContext<'tcx>,
-    hashes: IncrementalHashesMap,
-}
-
-impl<'a, 'tcx: 'a> ComputeItemHashesVisitor<'a, 'tcx> {
-    fn compute_and_store_ich_for_item_like<T>(&mut self,
-                                              def_index: DefIndex,
-                                              hash_bodies: bool,
-                                              item_like: T)
-        where T: HashStable<StableHashingContext<'tcx>>
-    {
-        if !hash_bodies && !self.tcx.sess.opts.build_dep_graph() {
-            // If we just need the hashes in order to compute the SVH, we don't
-            // need have two hashes per item. Just the one containing also the
-            // item's body is sufficient.
-            return
-        }
-
-        let def_path_hash = self.hcx.local_def_path_hash(def_index);
-
-        let mut hasher = IchHasher::new();
-        self.hcx.while_hashing_hir_bodies(hash_bodies, |hcx| {
-            item_like.hash_stable(hcx, &mut hasher);
-        });
-
-        let bytes_hashed = hasher.bytes_hashed();
-        let item_hash = hasher.finish();
-        let dep_node = if hash_bodies {
-            def_path_hash.to_dep_node(DepKind::HirBody)
-        } else {
-            def_path_hash.to_dep_node(DepKind::Hir)
-        };
-        debug!("calculate_def_hash: dep_node={:?} hash={:?}", dep_node, item_hash);
-        self.hashes.insert(dep_node, item_hash);
-
-        let bytes_hashed =
-            self.tcx.sess.perf_stats.incr_comp_bytes_hashed.get() + bytes_hashed;
-        self.tcx.sess.perf_stats.incr_comp_bytes_hashed.set(bytes_hashed);
-
-        if hash_bodies {
-            let in_scope_traits_map = self.tcx.in_scope_traits_map(def_index);
-            let mut hasher = IchHasher::new();
-            in_scope_traits_map.hash_stable(&mut self.hcx, &mut hasher);
-            let dep_node = def_path_hash.to_dep_node(DepKind::InScopeTraits);
-            self.hashes.insert(dep_node, hasher.finish());
-        }
-    }
-
-    fn compute_crate_hash(&mut self) {
-        let krate = self.tcx.hir.krate();
-
-        let mut crate_state = IchHasher::new();
-
-        let crate_disambiguator = self.tcx.sess.local_crate_disambiguator();
-        "crate_disambiguator".hash(&mut crate_state);
-        crate_disambiguator.as_str().len().hash(&mut crate_state);
-        crate_disambiguator.as_str().hash(&mut crate_state);
-
-        // add each item (in some deterministic order) to the overall
-        // crate hash.
-        {
-            let mut item_hashes: Vec<_> =
-                self.hashes.iter()
-                           .filter_map(|(&item_dep_node, &item_hash)| {
-                                // This `match` determines what kinds of nodes
-                                // go into the SVH:
-                                match item_dep_node.kind {
-                                    DepKind::InScopeTraits |
-                                    DepKind::Hir |
-                                    DepKind::HirBody => {
-                                        // We want to incoporate these into the
-                                        // SVH.
-                                    }
-                                    DepKind::AllLocalTraitImpls => {
-                                        // These are already covered by hashing
-                                        // the HIR.
-                                        return None
-                                    }
-                                    ref other => {
-                                        bug!("Found unexpected DepKind during \
-                                              SVH computation: {:?}",
-                                             other)
-                                    }
-                                }
-
-                                Some((item_dep_node, item_hash))
-                           })
-                           .collect();
-            item_hashes.sort_unstable(); // avoid artificial dependencies on item ordering
-            item_hashes.hash(&mut crate_state);
-        }
-
-        krate.attrs.hash_stable(&mut self.hcx, &mut crate_state);
-
-        let crate_hash = crate_state.finish();
-        self.hashes.insert(DepNode::new_no_params(DepKind::Krate), crate_hash);
-        debug!("calculate_crate_hash: crate_hash={:?}", crate_hash);
-    }
-
-    fn hash_crate_root_module(&mut self, krate: &'tcx hir::Crate) {
-        let hir::Crate {
-            ref module,
-            // Crate attributes are not copied over to the root `Mod`, so hash
-            // them explicitly here.
-            ref attrs,
-            span,
-
-            // These fields are handled separately:
-            exported_macros: _,
-            items: _,
-            trait_items: _,
-            impl_items: _,
-            bodies: _,
-            trait_impls: _,
-            trait_default_impl: _,
-            body_ids: _,
-        } = *krate;
-
-        self.compute_and_store_ich_for_item_like(CRATE_DEF_INDEX,
-                                                 false,
-                                                 (module, (span, attrs)));
-        self.compute_and_store_ich_for_item_like(CRATE_DEF_INDEX,
-                                                 true,
-                                                 (module, (span, attrs)));
-    }
-
-    fn compute_and_store_ich_for_trait_impls(&mut self, krate: &'tcx hir::Crate)
-    {
-        let tcx = self.tcx;
-
-        let mut impls: Vec<(DefPathHash, Fingerprint)> = krate
-            .trait_impls
-            .iter()
-            .map(|(&trait_id, impls)| {
-                let trait_id = tcx.def_path_hash(trait_id);
-                let mut impls: AccumulateVec<[_; 32]> = impls
-                    .iter()
-                    .map(|&node_id| {
-                        let def_id = tcx.hir.local_def_id(node_id);
-                        tcx.def_path_hash(def_id)
-                    })
-                    .collect();
-
-                impls.sort_unstable();
-                let mut hasher = StableHasher::new();
-                impls.hash_stable(&mut self.hcx, &mut hasher);
-                (trait_id, hasher.finish())
-            })
-            .collect();
-
-        impls.sort_unstable();
-
-        let mut default_impls: AccumulateVec<[_; 32]> = krate
-            .trait_default_impl
-            .iter()
-            .map(|(&trait_def_id, &impl_node_id)| {
-                let impl_def_id = tcx.hir.local_def_id(impl_node_id);
-                (tcx.def_path_hash(trait_def_id), tcx.def_path_hash(impl_def_id))
-            })
-            .collect();
-
-        default_impls.sort_unstable();
-
-        let mut hasher = StableHasher::new();
-        impls.hash_stable(&mut self.hcx, &mut hasher);
-
-        self.hashes.insert(DepNode::new_no_params(DepKind::AllLocalTraitImpls),
-                           hasher.finish());
-    }
-}
-
-impl<'a, 'tcx: 'a> ItemLikeVisitor<'tcx> for ComputeItemHashesVisitor<'a, 'tcx> {
-    fn visit_item(&mut self, item: &'tcx hir::Item) {
-        let def_index = self.tcx.hir.local_def_id(item.id).index;
-        self.compute_and_store_ich_for_item_like(def_index,
-                                                 false,
-                                                 item);
-        self.compute_and_store_ich_for_item_like(def_index,
-                                                 true,
-                                                 item);
-    }
-
-    fn visit_trait_item(&mut self, item: &'tcx hir::TraitItem) {
-        let def_index = self.tcx.hir.local_def_id(item.id).index;
-        self.compute_and_store_ich_for_item_like(def_index,
-                                                 false,
-                                                 item);
-        self.compute_and_store_ich_for_item_like(def_index,
-                                                 true,
-                                                 item);
-    }
-
-    fn visit_impl_item(&mut self, item: &'tcx hir::ImplItem) {
-        let def_index = self.tcx.hir.local_def_id(item.id).index;
-        self.compute_and_store_ich_for_item_like(def_index,
-                                                 false,
-                                                 item);
-        self.compute_and_store_ich_for_item_like(def_index,
-                                                 true,
-                                                 item);
-    }
-}
-
-
-
-pub fn compute_incremental_hashes_map<'a, 'tcx: 'a>(tcx: TyCtxt<'a, 'tcx, 'tcx>)
-                                                    -> IncrementalHashesMap {
-    let _ignore = tcx.dep_graph.in_ignore();
-    let krate = tcx.hir.krate();
-
-    let mut visitor = ComputeItemHashesVisitor {
-        tcx,
-        hcx: tcx.create_stable_hashing_context(),
-        hashes: IncrementalHashesMap::new(),
-    };
-
-    record_time(&tcx.sess.perf_stats.incr_comp_hashes_time, || {
-        visitor.hash_crate_root_module(krate);
-        krate.visit_all_item_likes(&mut visitor);
-
-        for macro_def in krate.exported_macros.iter() {
-            let def_index = tcx.hir.local_def_id(macro_def.id).index;
-            visitor.compute_and_store_ich_for_item_like(def_index,
-                                                        false,
-                                                        macro_def);
-            visitor.compute_and_store_ich_for_item_like(def_index,
-                                                        true,
-                                                        macro_def);
-        }
-
-        visitor.compute_and_store_ich_for_trait_impls(krate);
-    });
-
-    tcx.sess.perf_stats.incr_comp_hashes_count.set(visitor.hashes.len() as u64);
-
-    record_time(&tcx.sess.perf_stats.svh_time, || visitor.compute_crate_hash());
-    visitor.hashes
-}
diff --git a/src/librustc_incremental/lib.rs b/src/librustc_incremental/lib.rs
index 3c1e02f8a5a..6817856fdb1 100644
--- a/src/librustc_incremental/lib.rs
+++ b/src/librustc_incremental/lib.rs
@@ -28,13 +28,9 @@ extern crate syntax;
 extern crate syntax_pos;
 
 mod assert_dep_graph;
-mod calculate_svh;
 mod persist;
 
 pub use assert_dep_graph::assert_dep_graph;
-pub use calculate_svh::compute_incremental_hashes_map;
-pub use calculate_svh::IncrementalHashesMap;
-pub use calculate_svh::IchHasher;
 pub use persist::load_dep_graph;
 pub use persist::save_dep_graph;
 pub use persist::save_trans_partition;
diff --git a/src/librustc_incremental/persist/load.rs b/src/librustc_incremental/persist/load.rs
index 21e0dce7ad6..0d6257e4245 100644
--- a/src/librustc_incremental/persist/load.rs
+++ b/src/librustc_incremental/persist/load.rs
@@ -11,18 +11,17 @@
 //! Code to save/load the dep-graph from files.
 
 use rustc::dep_graph::{DepNode, WorkProductId, DepKind};
-use rustc::hir::def_id::DefId;
 use rustc::hir::svh::Svh;
 use rustc::ich::Fingerprint;
 use rustc::session::Session;
 use rustc::ty::TyCtxt;
+use rustc::util::nodemap::DefIdMap;
 use rustc_data_structures::fx::{FxHashSet, FxHashMap};
 use rustc_data_structures::indexed_vec::IndexVec;
 use rustc_serialize::Decodable as RustcDecodable;
 use rustc_serialize::opaque::Decoder;
 use std::path::{Path};
 
-use IncrementalHashesMap;
 use super::data::*;
 use super::dirty_clean;
 use super::hash::*;
@@ -40,17 +39,15 @@ pub type DirtyNodes = FxHashMap<DepNodeIndex, DepNodeIndex>;
 /// early in compilation, before we've really done any work, but
 /// actually it doesn't matter all that much.) See `README.md` for
 /// more general overview.
-pub fn load_dep_graph<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
-                                incremental_hashes_map: &IncrementalHashesMap) {
+pub fn load_dep_graph<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>) {
     tcx.precompute_in_scope_traits_hashes();
     if tcx.sess.incr_session_load_dep_graph() {
         let _ignore = tcx.dep_graph.in_ignore();
-        load_dep_graph_if_exists(tcx, incremental_hashes_map);
+        load_dep_graph_if_exists(tcx);
     }
 }
 
-fn load_dep_graph_if_exists<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
-                                      incremental_hashes_map: &IncrementalHashesMap) {
+fn load_dep_graph_if_exists<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>) {
     let dep_graph_path = dep_graph_path(tcx.sess);
     let dep_graph_data = match load_data(tcx.sess, &dep_graph_path) {
         Some(p) => p,
@@ -63,7 +60,7 @@ fn load_dep_graph_if_exists<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
         None => return // no file
     };
 
-    match decode_dep_graph(tcx, incremental_hashes_map, &dep_graph_data, &work_products_data) {
+    match decode_dep_graph(tcx, &dep_graph_data, &work_products_data) {
         Ok(dirty_nodes) => dirty_nodes,
         Err(err) => {
             tcx.sess.warn(
@@ -118,7 +115,6 @@ fn does_still_exist(tcx: TyCtxt, dep_node: &DepNode) -> bool {
 /// Decode the dep graph and load the edges/nodes that are still clean
 /// into `tcx.dep_graph`.
 pub fn decode_dep_graph<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
-                                  incremental_hashes_map: &IncrementalHashesMap,
                                   dep_graph_data: &[u8],
                                   work_products_data: &[u8])
                                   -> Result<(), String>
@@ -193,9 +189,6 @@ pub fn decode_dep_graph<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
     dirty_clean::check_dirty_clean_annotations(tcx,
                                                &serialized_dep_graph.nodes,
                                                &dirty_raw_nodes);
-
-    load_prev_metadata_hashes(tcx,
-                              &mut *incremental_hashes_map.prev_metadata_hashes.borrow_mut());
     Ok(())
 }
 
@@ -309,11 +302,12 @@ fn delete_dirty_work_product(tcx: TyCtxt,
     work_product::delete_workproduct_files(tcx.sess, &swp.work_product);
 }
 
-fn load_prev_metadata_hashes(tcx: TyCtxt,
-                             output: &mut FxHashMap<DefId, Fingerprint>) {
+pub fn load_prev_metadata_hashes(tcx: TyCtxt) -> DefIdMap<Fingerprint> {
+    let mut output = DefIdMap();
+
     if !tcx.sess.opts.debugging_opts.query_dep_graph {
         // Previous metadata hashes are only needed for testing.
-        return
+        return output
     }
 
     debug!("load_prev_metadata_hashes() - Loading previous metadata hashes");
@@ -323,7 +317,7 @@ fn load_prev_metadata_hashes(tcx: TyCtxt,
     if !file_path.exists() {
         debug!("load_prev_metadata_hashes() - Couldn't find file containing \
                 hashes at `{}`", file_path.display());
-        return
+        return output
     }
 
     debug!("load_prev_metadata_hashes() - File: {}", file_path.display());
@@ -333,12 +327,12 @@ fn load_prev_metadata_hashes(tcx: TyCtxt,
         Ok(None) => {
             debug!("load_prev_metadata_hashes() - File produced by incompatible \
                     compiler version: {}", file_path.display());
-            return
+            return output
         }
         Err(err) => {
             debug!("load_prev_metadata_hashes() - Error reading file `{}`: {}",
                    file_path.display(), err);
-            return
+            return output
         }
     };
 
@@ -362,6 +356,8 @@ fn load_prev_metadata_hashes(tcx: TyCtxt,
 
     debug!("load_prev_metadata_hashes() - successfully loaded {} hashes",
            serialized_hashes.index_map.len());
+
+    output
 }
 
 fn process_edge<'a, 'tcx, 'edges>(
diff --git a/src/librustc_incremental/persist/save.rs b/src/librustc_incremental/persist/save.rs
index 72f76670ee1..e2d03fcb0e1 100644
--- a/src/librustc_incremental/persist/save.rs
+++ b/src/librustc_incremental/persist/save.rs
@@ -15,6 +15,7 @@ use rustc::ich::Fingerprint;
 use rustc::middle::cstore::EncodedMetadataHashes;
 use rustc::session::Session;
 use rustc::ty::TyCtxt;
+use rustc::util::nodemap::DefIdMap;
 use rustc_data_structures::fx::FxHashMap;
 use rustc_data_structures::graph;
 use rustc_data_structures::indexed_vec::IndexVec;
@@ -24,7 +25,6 @@ use std::io::{self, Cursor, Write};
 use std::fs::{self, File};
 use std::path::PathBuf;
 
-use IncrementalHashesMap;
 use super::data::*;
 use super::hash::*;
 use super::preds::*;
@@ -33,8 +33,9 @@ use super::dirty_clean;
 use super::file_format;
 use super::work_product;
 
+use super::load::load_prev_metadata_hashes;
+
 pub fn save_dep_graph<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
-                                incremental_hashes_map: IncrementalHashesMap,
                                 metadata_hashes: &EncodedMetadataHashes,
                                 svh: Svh) {
     debug!("save_dep_graph()");
@@ -51,6 +52,14 @@ pub fn save_dep_graph<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
         eprintln!("incremental: {} edges in dep-graph", query.graph.len_edges());
     }
 
+    // We load the previous metadata hashes now before overwriting the file
+    // (if we need them for testing).
+    let prev_metadata_hashes = if tcx.sess.opts.debugging_opts.query_dep_graph {
+        load_prev_metadata_hashes(tcx)
+    } else {
+        DefIdMap()
+    };
+
     let mut hcx = HashContext::new(tcx);
     let preds = Predecessors::new(&query, &mut hcx);
     let mut current_metadata_hashes = FxHashMap();
@@ -73,9 +82,8 @@ pub fn save_dep_graph<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
             dep_graph_path(sess),
             |e| encode_dep_graph(tcx, &preds, e));
 
-    let prev_metadata_hashes = incremental_hashes_map.prev_metadata_hashes.borrow();
     dirty_clean::check_dirty_clean_metadata(tcx,
-                                            &*prev_metadata_hashes,
+                                            &prev_metadata_hashes,
                                             &current_metadata_hashes);
 }
 
diff --git a/src/librustc_trans/back/link.rs b/src/librustc_trans/back/link.rs
index 08266e86f97..9d13d4ce15b 100644
--- a/src/librustc_trans/back/link.rs
+++ b/src/librustc_trans/back/link.rs
@@ -20,17 +20,16 @@ use rustc::session::config::{self, NoDebugInfo, OutputFilenames, OutputType, Pri
 use rustc::session::filesearch;
 use rustc::session::search_paths::PathKind;
 use rustc::session::Session;
+use rustc::ich::Fingerprint;
 use rustc::middle::cstore::{LinkMeta, NativeLibrary, LibSource, NativeLibraryKind};
 use rustc::middle::dependency_format::Linkage;
 use {CrateTranslation, CrateInfo};
 use rustc::util::common::time;
 use rustc::util::fs::fix_windows_verbatim_for_gcc;
-use rustc::dep_graph::{DepKind, DepNode};
 use rustc::hir::def_id::CrateNum;
 use rustc::hir::svh::Svh;
 use rustc_back::tempdir::TempDir;
 use rustc_back::{PanicStrategy, RelroLevel};
-use rustc_incremental::IncrementalHashesMap;
 use context::get_reloc_model;
 use llvm;
 
@@ -92,10 +91,9 @@ pub const RLIB_BYTECODE_OBJECT_V1_DATA_OFFSET: usize =
 pub use self::rustc_trans_utils::link::{find_crate_name, filename_for_input,
                                         default_output_for_target, invalid_output_for_target};
 
-pub fn build_link_meta(incremental_hashes_map: &IncrementalHashesMap) -> LinkMeta {
-    let krate_dep_node = &DepNode::new_no_params(DepKind::Krate);
+pub fn build_link_meta(crate_hash: Fingerprint) -> LinkMeta {
     let r = LinkMeta {
-        crate_hash: Svh::new(incremental_hashes_map[krate_dep_node].to_smaller_hash()),
+        crate_hash: Svh::new(crate_hash.to_smaller_hash()),
     };
     info!("{:?}", r);
     return r;
diff --git a/src/librustc_trans/base.rs b/src/librustc_trans/base.rs
index ba15f3522ac..bfa18d84d27 100644
--- a/src/librustc_trans/base.rs
+++ b/src/librustc_trans/base.rs
@@ -41,12 +41,13 @@ use rustc::middle::trans::{Linkage, Visibility, Stats};
 use rustc::middle::cstore::{EncodedMetadata, EncodedMetadataHashes};
 use rustc::ty::{self, Ty, TyCtxt};
 use rustc::ty::maps::Providers;
+use rustc::dep_graph::{DepNode, DepKind};
 use rustc::middle::cstore::{self, LinkMeta, LinkagePreference};
 use rustc::hir::map as hir_map;
 use rustc::util::common::{time, print_time_passes_entry};
 use rustc::session::config::{self, NoDebugInfo};
 use rustc::session::Session;
-use rustc_incremental::{self, IncrementalHashesMap};
+use rustc_incremental;
 use abi;
 use allocator;
 use mir::lvalue::LvalueRef;
@@ -935,12 +936,15 @@ pub fn find_exported_symbols(tcx: TyCtxt) -> NodeSet {
 }
 
 pub fn trans_crate<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
-                             incremental_hashes_map: IncrementalHashesMap,
                              rx: mpsc::Receiver<Box<Any + Send>>)
                              -> OngoingCrateTranslation {
     check_for_rustc_errors_attr(tcx);
 
-    let link_meta = link::build_link_meta(&incremental_hashes_map);
+
+    let crate_hash = tcx.dep_graph
+                        .fingerprint_of(&DepNode::new_no_params(DepKind::Krate))
+                        .unwrap();
+    let link_meta = link::build_link_meta(crate_hash);
     let exported_symbol_node_ids = find_exported_symbols(tcx);
 
     let shared_ccx = SharedCrateContext::new(tcx);
@@ -980,7 +984,6 @@ pub fn trans_crate<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
         ongoing_translation.translation_finished(tcx);
 
         assert_and_save_dep_graph(tcx,
-                                  incremental_hashes_map,
                                   metadata_incr_hashes,
                                   link_meta);
 
@@ -1113,7 +1116,6 @@ pub fn trans_crate<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
     ongoing_translation.check_for_errors(tcx.sess);
 
     assert_and_save_dep_graph(tcx,
-                              incremental_hashes_map,
                               metadata_incr_hashes,
                               link_meta);
     ongoing_translation
@@ -1124,7 +1126,6 @@ pub fn trans_crate<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
 thread_local!(static DISPOSITIONS: RefCell<Vec<(String, Disposition)>> = Default::default());
 
 fn assert_and_save_dep_graph<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
-                                       incremental_hashes_map: IncrementalHashesMap,
                                        metadata_incr_hashes: EncodedMetadataHashes,
                                        link_meta: LinkMeta) {
     time(tcx.sess.time_passes(),
@@ -1134,7 +1135,6 @@ fn assert_and_save_dep_graph<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
     time(tcx.sess.time_passes(),
          "serialize dep graph",
          || rustc_incremental::save_dep_graph(tcx,
-                                              incremental_hashes_map,
                                               &metadata_incr_hashes,
                                               link_meta.crate_hash));
 }
diff --git a/src/librustc_trans/partitioning.rs b/src/librustc_trans/partitioning.rs
index 9b617c35d93..7c29186f465 100644
--- a/src/librustc_trans/partitioning.rs
+++ b/src/librustc_trans/partitioning.rs
@@ -108,11 +108,12 @@ use rustc::dep_graph::{DepNode, WorkProductId};
 use rustc::hir::def_id::DefId;
 use rustc::hir::map::DefPathData;
 use rustc::middle::trans::{Linkage, Visibility};
+use rustc::ich::Fingerprint;
 use rustc::session::config::NUMBERED_CODEGEN_UNIT_MARKER;
 use rustc::ty::{self, TyCtxt, InstanceDef};
 use rustc::ty::item_path::characteristic_def_id_of_type;
 use rustc::util::nodemap::{FxHashMap, FxHashSet};
-use rustc_incremental::IchHasher;
+use rustc_data_structures::stable_hasher::StableHasher;
 use std::collections::hash_map::Entry;
 use std::hash::Hash;
 use syntax::ast::NodeId;
@@ -155,7 +156,7 @@ pub trait CodegenUnitExt<'tcx> {
     }
 
     fn compute_symbol_name_hash<'a>(&self, tcx: TyCtxt<'a, 'tcx, 'tcx>) -> u64 {
-        let mut state = IchHasher::new();
+        let mut state: StableHasher<Fingerprint> = StableHasher::new();
         let all_items = self.items_in_deterministic_order(tcx);
         for (item, (linkage, visibility)) in all_items {
             let symbol_name = item.symbol_name(tcx);
diff --git a/src/librustdoc/core.rs b/src/librustdoc/core.rs
index 1663e5ad142..2ecb7b546fc 100644
--- a/src/librustdoc/core.rs
+++ b/src/librustdoc/core.rs
@@ -175,7 +175,7 @@ pub fn run_core(search_paths: SearchPaths,
 
     let arena = DroplessArena::new();
     let arenas = GlobalArenas::new();
-    let hir_map = hir_map::map_crate(&mut hir_forest, &defs);
+    let hir_map = hir_map::map_crate(&sess, &*cstore, &mut hir_forest, &defs);
     let output_filenames = driver::build_output_filenames(&input,
                                                           &None,
                                                           &None,
@@ -191,7 +191,7 @@ pub fn run_core(search_paths: SearchPaths,
                                                      &arenas,
                                                      &name,
                                                      &output_filenames,
-                                                     |tcx, analysis, _, _, result| {
+                                                     |tcx, analysis, _, result| {
         if let Err(_) = result {
             sess.fatal("Compilation failed, aborting rustdoc");
         }
diff --git a/src/librustdoc/test.rs b/src/librustdoc/test.rs
index 36efc37a809..f9cb4b84545 100644
--- a/src/librustdoc/test.rs
+++ b/src/librustdoc/test.rs
@@ -124,7 +124,7 @@ pub fn run(input: &str,
                                        render_type);
 
     {
-        let map = hir::map::map_crate(&mut hir_forest, &defs);
+        let map = hir::map::map_crate(&sess, &*cstore, &mut hir_forest, &defs);
         let krate = map.krate();
         let mut hir_collector = HirCollector {
             sess: &sess,