librustc: Stop calling `each_path` in coherence.

10% win or so for small crates.

src/librustc/metadata/common.rs

@@ -182,6 +182,9 @@ pub fn from_uint(value : uint) -> Option<astencode_tag> {
 pub static tag_item_method_provided_source: uint = 0x81;
 pub static tag_item_impl_vtables: uint = 0x82;
 
+pub static tag_impls: uint = 0x83;
+pub static tag_impls_impl: uint = 0x84;
+
 pub struct LinkMeta {
     name: @str,
     vers: @str,

src/librustc/metadata/csearch.rs

@@ -246,3 +246,11 @@ pub fn get_link_args_for_crate(cstore: @mut cstore::CStore,
     let cdata = cstore::get_crate_data(cstore, crate_num);
     decoder::get_link_args_for_crate(cdata)
 }
+
+pub fn each_impl(cstore: @mut cstore::CStore,
+                 crate_num: ast::CrateNum,
+                 callback: &fn(ast::def_id)) {
+    let cdata = cstore::get_crate_data(cstore, crate_num);
+    decoder::each_impl(cdata, callback)
+}
+

src/librustc/metadata/decoder.rs

@@ -1316,3 +1316,13 @@ pub fn get_link_args_for_crate(cdata: cmd) -> ~[~str] {
     };
     result
 }
+
+pub fn each_impl(cdata: cmd, callback: &fn(ast::def_id)) {
+    let impls_doc = reader::get_doc(reader::Doc(cdata.data), tag_impls);
+    let _ = do reader::tagged_docs(impls_doc, tag_impls_impl) |impl_doc| {
+        callback(item_def_id(impl_doc, cdata));
+        true
+    };
+}
+
+

src/librustc/metadata/encoder.rs

@@ -39,6 +39,7 @@
 use syntax::diagnostic::span_handler;
 use syntax::parse::token::special_idents;
 use syntax::ast_util;
+use syntax::visit::Visitor;
 use syntax::visit;
 use syntax::parse::token;
 use syntax;
@@ -72,6 +73,7 @@ struct Stats {
     dep_bytes: uint,
     lang_item_bytes: uint,
     link_args_bytes: uint,
+    impl_bytes: uint,
     misc_bytes: uint,
     item_bytes: uint,
     index_bytes: uint,
@@ -1221,7 +1223,10 @@ struct EncodeVisitor {
 }
 
 impl visit::Visitor<()> for EncodeVisitor {
-    fn visit_expr(&mut self, ex:@expr, _:()) { my_visit_expr(ex); }
+    fn visit_expr(&mut self, ex:@expr, _:()) {
+        visit::walk_expr(self, ex, ());
+        my_visit_expr(ex);
+    }
     fn visit_item(&mut self, i:@item, _:()) {
         visit::walk_item(self, i, ());
         my_visit_item(i,
@@ -1510,6 +1515,41 @@ fn encode_link_args(ecx: &EncodeContext, ebml_w: &mut writer::Encoder) {
     ebml_w.end_tag();
 }
 
+struct ImplVisitor<'self> {
+    ecx: &'self EncodeContext<'self>,
+    ebml_w: &'self mut writer::Encoder,
+}
+
+impl<'self> Visitor<()> for ImplVisitor<'self> {
+    fn visit_item(&mut self, item: @item, _: ()) {
+        match item.node {
+            item_impl(*) => {
+                self.ebml_w.start_tag(tag_impls_impl);
+                encode_def_id(self.ebml_w, local_def(item.id));
+                self.ebml_w.end_tag();
+            }
+            _ => {}
+        }
+        visit::walk_item(self, item, ());
+    }
+}
+
+fn encode_impls(ecx: &EncodeContext,
+                crate: &Crate,
+                ebml_w: &mut writer::Encoder) {
+    ebml_w.start_tag(tag_impls);
+
+    {
+        let mut visitor = ImplVisitor {
+            ecx: ecx,
+            ebml_w: ebml_w,
+        };
+        visit::walk_crate(&mut visitor, crate, ());
+    }
+
+    ebml_w.end_tag();
+}
+
 fn encode_misc_info(ecx: &EncodeContext,
                     crate: &Crate,
                     ebml_w: &mut writer::Encoder) {
@@ -1574,6 +1614,7 @@ pub fn encode_metadata(parms: EncodeParams, crate: &Crate) -> ~[u8] {
         dep_bytes: 0,
         lang_item_bytes: 0,
         link_args_bytes: 0,
+        impl_bytes: 0,
         misc_bytes: 0,
         item_bytes: 0,
         index_bytes: 0,
@@ -1632,6 +1673,11 @@ pub fn encode_metadata(parms: EncodeParams, crate: &Crate) -> ~[u8] {
     encode_link_args(&ecx, &mut ebml_w);
     ecx.stats.link_args_bytes = *wr.pos - i;
 
+    // Encode the def IDs of impls, for coherence checking.
+    i = *wr.pos;
+    encode_impls(&ecx, crate, &mut ebml_w);
+    ecx.stats.impl_bytes = *wr.pos - i;
+
     // Encode miscellaneous info.
     i = *wr.pos;
     encode_misc_info(&ecx, crate, &mut ebml_w);
@@ -1664,6 +1710,7 @@ pub fn encode_metadata(parms: EncodeParams, crate: &Crate) -> ~[u8] {
         printfln!("       dep bytes: %u", ecx.stats.dep_bytes);
         printfln!(" lang item bytes: %u", ecx.stats.lang_item_bytes);
         printfln!(" link args bytes: %u", ecx.stats.link_args_bytes);
+        printfln!("      impl bytes: %u", ecx.stats.impl_bytes);
         printfln!("      misc bytes: %u", ecx.stats.misc_bytes);
         printfln!("      item bytes: %u", ecx.stats.item_bytes);
         printfln!("     index bytes: %u", ecx.stats.index_bytes);

src/librustc/middle/typeck/coherence.rs

@@ -15,10 +15,9 @@
 // each trait in the system to its implementations.
 
 
-use metadata::csearch::{each_path, get_impl_trait};
+use metadata::csearch::{each_impl, get_impl_trait};
 use metadata::csearch;
 use metadata::cstore::iter_crate_data;
-use metadata::decoder::{dl_def, dl_field, dl_impl};
 use middle::ty::get;
 use middle::ty::{lookup_item_type, subst};
 use middle::ty::{substs, t, ty_bool, ty_bot, ty_box, ty_enum, ty_err};
@@ -680,9 +679,6 @@ pub fn add_external_impl(&self,
         let tcx = self.crate_context.tcx;
         let implementation = @csearch::get_impl(tcx, impl_def_id);
 
-        debug!("coherence: adding impl from external crate: %s",
-               ty::item_path_str(tcx, implementation.did));
-
         // Make sure we don't visit the same implementation multiple times.
         if !impls_seen.insert(implementation.did) {
             // Skip this one.
@@ -752,15 +748,10 @@ pub fn add_external_crates(&self) {
 
         let crate_store = self.crate_context.tcx.sess.cstore;
         do iter_crate_data(crate_store) |crate_number, _crate_metadata| {
-            do each_path(crate_store, crate_number) |_, def_like, _| {
-                match def_like {
-                    dl_impl(def_id) => {
-                        self.add_external_impl(&mut impls_seen, def_id)
-                    }
-                    dl_def(_) | dl_field => (),   // Skip this.
-                }
-                true
-            };
+            do each_impl(crate_store, crate_number) |def_id| {
+                assert_eq!(crate_number, def_id.crate);
+                self.add_external_impl(&mut impls_seen, def_id)
+            }
         }
     }
 

src/libstd/rt/borrowck.rs

@@ -38,7 +38,7 @@ pub struct BorrowRecord {
 }
 
 fn try_take_task_borrow_list() -> Option<~[BorrowRecord]> {
-    do Local::borrow::<Task, Option<~[BorrowRecord]>> |task| {
+    do Local::borrow |task: &mut Task| {
         task.borrow_list.take()
     }
 }
@@ -50,7 +50,7 @@ fn swap_task_borrow_list(f: &fn(~[BorrowRecord]) -> ~[BorrowRecord]) {
     };
     let borrows = f(borrows);
     let borrows = Cell::new(borrows);
-    do Local::borrow::<Task, ()> |task| {
+    do Local::borrow |task: &mut Task| {
         task.borrow_list = Some(borrows.take());
     }
 }

src/libstd/rt/sched.rs

@@ -555,7 +555,7 @@ pub fn change_task_context(~self,
             let current_task: &mut Task = match sched.cleanup_job {
                 Some(CleanupJob { task: ref task, _ }) => {
                     let task_ptr: *~Task = task;
-                    transmute_mut_region(*transmute_mut_unsafe(task))
+                    transmute_mut_region(*transmute_mut_unsafe(task_ptr))
                 }
                 None => {
                     rtabort!("no cleanup job");