From 17daf1f9bf4e78c9f3ed8be24ef4bc15d60c744e Mon Sep 17 00:00:00 2001
From: Patrick Walton <pcwalton@mimiga.net>
Date: Tue, 10 May 2011 14:47:28 -0700
Subject: [PATCH] rustc: Cache intermediate results of metadata.Encode.ty_str.
 Shaves 30% off translation time.

---
 src/comp/middle/metadata.rs | 14 +++++++++++++-
 src/comp/middle/trans.rs    |  4 ++++
 src/comp/middle/ty.rs       |  7 +++++--
 3 files changed, 22 insertions(+), 3 deletions(-)

diff --git a/src/comp/middle/metadata.rs b/src/comp/middle/metadata.rs
index dee9046d77f..dfc441a92fd 100644
--- a/src/comp/middle/metadata.rs
+++ b/src/comp/middle/metadata.rs
@@ -82,7 +82,19 @@ mod Encode {
 
     fn enc_ty(&IO.writer w, &@ctxt cx, &ty.t t) {
         alt (cx.abbrevs) {
-            case (ac_no_abbrevs) { enc_sty(w, cx, ty.struct(cx.tcx, t)); }
+            case (ac_no_abbrevs) {
+                auto result_str;
+                alt (cx.tcx.short_names_cache.find(t)) {
+                    case (some[str](?s)) { result_str = s; }
+                    case (none[str]) {
+                        auto sw = IO.string_writer();
+                        enc_sty(sw.get_writer(), cx, ty.struct(cx.tcx, t));
+                        result_str = sw.get_str();
+                        cx.tcx.short_names_cache.insert(t, result_str);
+                    }
+                }
+                w.write_str(result_str);
+            }
             case (ac_use_abbrevs(?abbrevs)) {
                 alt (abbrevs.find(t)) {
                     case (some[ty_abbrev](?a)) {
diff --git a/src/comp/middle/trans.rs b/src/comp/middle/trans.rs
index 033deed3936..31a7361e200 100644
--- a/src/comp/middle/trans.rs
+++ b/src/comp/middle/trans.rs
@@ -113,6 +113,7 @@ state type crate_ctxt = rec(session.session sess,
                             std.SHA1.sha1 sha,
                             hashmap[ty.t, str] type_sha1s,
                             hashmap[ty.t, metadata.ty_abbrev] type_abbrevs,
+                            hashmap[ty.t, str] type_short_names,
                             ty.ctxt tcx,
                             @upcall.upcalls upcalls);
 
@@ -192,6 +193,7 @@ fn get_type_sha1(@crate_ctxt ccx, ty.t t) -> str {
             // NB: do *not* use abbrevs here as we want the symbol names
             // to be independent of one another in the crate.
             auto cx = @rec(ds=f, tcx=ccx.tcx, abbrevs=metadata.ac_no_abbrevs);
+
             ccx.sha.input_str(metadata.Encode.ty_str(cx, t));
             hash = Str.substr(ccx.sha.result_str(), 0u, 16u);
             ccx.type_sha1s.insert(t, hash);
@@ -7694,6 +7696,7 @@ fn trans_crate(session.session sess, @ast.crate crate, ty.ctxt tcx,
     auto lltypes = Map.mk_hashmap[ty.t,TypeRef](hasher, eqer);
     auto sha1s = Map.mk_hashmap[ty.t,str](hasher, eqer);
     auto abbrevs = Map.mk_hashmap[ty.t,metadata.ty_abbrev](hasher, eqer);
+    auto short_names = Map.mk_hashmap[ty.t,str](hasher, eqer);
 
     auto ccx = @rec(sess = sess,
                     llmod = llmod,
@@ -7721,6 +7724,7 @@ fn trans_crate(session.session sess, @ast.crate crate, ty.ctxt tcx,
                     sha = std.SHA1.mk_sha1(),
                     type_sha1s = sha1s,
                     type_abbrevs = abbrevs,
+                    type_short_names = short_names,
                     tcx = tcx,
                     upcalls = upcall.declare_upcalls(tn, llmod));
     auto cx = new_local_ctxt(ccx);
diff --git a/src/comp/middle/ty.rs b/src/comp/middle/ty.rs
index dfdf07d9c2f..797b1ee0bd6 100644
--- a/src/comp/middle/ty.rs
+++ b/src/comp/middle/ty.rs
@@ -55,7 +55,8 @@ type mt = rec(t ty, ast.mutability mut);
 type creader_cache = hashmap[tup(int,uint,uint),ty.t];
 type ctxt = rec(@type_store ts,
                 session.session sess,
-                creader_cache rcache);
+                creader_cache rcache,
+                hashmap[t,str] short_names_cache);
 type ty_ctxt = ctxt;    // Needed for disambiguation from Unify.ctxt.
 
 // Convert from method type to function type.  Pretty easy; we just drop
@@ -227,7 +228,9 @@ fn mk_rcache() -> creader_cache {
 fn mk_ctxt(session.session s) -> ctxt {
     ret rec(ts = mk_type_store(),
             sess = s,
-            rcache = mk_rcache());
+            rcache = mk_rcache(),
+            short_names_cache =
+                Map.mk_hashmap[ty.t,str](ty.hash_ty, ty.eq_ty));
 }
 // Type constructors