From b4a3d525d8a8c5c111958d09f8ffeee1cab6bda8 Mon Sep 17 00:00:00 2001
From: Brian Anderson <banderson@mozilla.com>
Date: Mon, 23 Apr 2012 23:40:53 -0700
Subject: [PATCH] rustc: Eliminate trans dependency from metadata::tyencode

---
 src/rustc/metadata/astencode.rs |  2 +-
 src/rustc/metadata/encoder.rs   | 17 +++++++++++------
 src/rustc/metadata/tyencode.rs  | 12 +++++++-----
 3 files changed, 19 insertions(+), 12 deletions(-)

diff --git a/src/rustc/metadata/astencode.rs b/src/rustc/metadata/astencode.rs
index ac0b07cef4b..787ee5ea73b 100644
--- a/src/rustc/metadata/astencode.rs
+++ b/src/rustc/metadata/astencode.rs
@@ -659,7 +659,7 @@ impl helpers for @e::encode_ctxt {
     fn ty_str_ctxt() -> @tyencode::ctxt {
         @{ds: e::def_to_str,
           tcx: self.ccx.tcx,
-          reachable: self.ccx.reachable,
+          reachable: encoder::reachable(self, _),
           abbrevs: tyencode::ac_use_abbrevs(self.type_abbrevs)}
     }
 }
diff --git a/src/rustc/metadata/encoder.rs b/src/rustc/metadata/encoder.rs
index dc53c10e3b6..8968be31ce7 100644
--- a/src/rustc/metadata/encoder.rs
+++ b/src/rustc/metadata/encoder.rs
@@ -20,6 +20,7 @@ import std::ebml::serializer;
 
 export encode_metadata;
 export encoded_ty;
+export reachable;
 
 // used by astencode:
 export def_to_str;
@@ -32,6 +33,10 @@ type abbrev_map = map::hashmap<ty::t, tyencode::ty_abbrev>;
 type encode_ctxt = {ccx: @crate_ctxt,
                     type_abbrevs: abbrev_map};
 
+fn reachable(ecx: @encode_ctxt, id: node_id) -> bool {
+    ecx.ccx.reachable.contains_key(id)
+}
+
 // Path table encoding
 fn encode_name(ebml_w: ebml::writer, name: str) {
     ebml_w.wr_tagged_str(tag_paths_data_name, name);
@@ -110,7 +115,7 @@ fn encode_module_item_paths(ebml_w: ebml::writer, ecx: @encode_ctxt,
                             module: _mod, path: [str], &index: [entry<str>]) {
     // FIXME factor out add_to_index/start/encode_name/encode_def_id/end ops
     for module.items.each {|it|
-        if !ecx.ccx.reachable.contains_key(it.id) ||
+        if !reachable(ecx, it.id) ||
            !ast_util::is_exported(it.ident, module) { cont; }
         alt it.node {
           item_const(_, _) {
@@ -235,7 +240,7 @@ fn encode_type_param_bounds(ebml_w: ebml::writer, ecx: @encode_ctxt,
                             params: [ty_param]) {
     let ty_str_ctxt = @{ds: def_to_str,
                         tcx: ecx.ccx.tcx,
-                        reachable: ecx.ccx.reachable,
+                        reachable: reachable(ecx, _),
                         abbrevs: tyencode::ac_use_abbrevs(ecx.type_abbrevs)};
     for params.each {|param|
         ebml_w.start_tag(tag_items_data_item_ty_param_bounds);
@@ -255,7 +260,7 @@ fn write_type(ecx: @encode_ctxt, ebml_w: ebml::writer, typ: ty::t) {
     let ty_str_ctxt =
         @{ds: def_to_str,
           tcx: ecx.ccx.tcx,
-          reachable: ecx.ccx.reachable,
+          reachable: reachable(ecx, _),
           abbrevs: tyencode::ac_use_abbrevs(ecx.type_abbrevs)};
     tyencode::enc_ty(ebml_w.writer, ty_str_ctxt, typ);
 }
@@ -489,7 +494,7 @@ fn encode_info_for_item(ecx: @encode_ctxt, ebml_w: ebml::writer, item: @item,
     let tcx = ecx.ccx.tcx;
     let must_write =
         alt item.node { item_enum(_, _, _) { true } _ { false } };
-    if !must_write && !ecx.ccx.reachable.contains_key(item.id) { ret; }
+    if !must_write && !reachable(ecx, item.id) { ret; }
 
     fn add_to_index_(item: @item, ebml_w: ebml::writer,
                      index: @mut [entry<int>]) {
@@ -704,7 +709,7 @@ fn encode_info_for_native_item(ecx: @encode_ctxt, ebml_w: ebml::writer,
                                nitem: @native_item,
                                index: @mut [entry<int>],
                                path: ast_map::path, abi: native_abi) {
-    if !ecx.ccx.reachable.contains_key(nitem.id) { ret; }
+    if !reachable(ecx, nitem.id) { ret; }
     *index += [{val: nitem.id, pos: ebml_w.writer.tell()}];
 
     ebml_w.start_tag(tag_items_data_item);
@@ -1019,7 +1024,7 @@ fn encode_metadata(cx: @crate_ctxt, crate: @crate) -> [u8] {
 fn encoded_ty(tcx: ty::ctxt, t: ty::t) -> str {
     let cx = @{ds: def_to_str,
                tcx: tcx,
-               reachable: std::map::int_hash(),
+               reachable: {|_id| false},
                abbrevs: tyencode::ac_no_abbrevs};
     let buf = io::mem_buffer();
     tyencode::enc_ty(io::mem_buffer_writer(buf), cx, t);
diff --git a/src/rustc/metadata/tyencode.rs b/src/rustc/metadata/tyencode.rs
index 9c63337970c..ae7f47e2f31 100644
--- a/src/rustc/metadata/tyencode.rs
+++ b/src/rustc/metadata/tyencode.rs
@@ -7,7 +7,6 @@ import driver::session::session;
 import middle::ty;
 import middle::ty::vid;
 import syntax::print::pprust::*;
-import middle::trans::reachable;
 
 export ctxt;
 export ty_abbrev;
@@ -17,11 +16,14 @@ export enc_ty;
 export enc_bounds;
 export enc_mode;
 
-type ctxt =
+type ctxt = {
     // Def -> str Callback:
+    ds: fn@(def_id) -> str,
     // The type context.
-    {ds: fn@(def_id) -> str, tcx: ty::ctxt,
-     reachable: reachable::map, abbrevs: abbrev_ctxt};
+    tcx: ty::ctxt,
+    reachable: fn@(node_id) -> bool,
+    abbrevs: abbrev_ctxt
+};
 
 // Compact string representation for ty.t values. API ty_str & parse_from_str.
 // Extra parameters are for converting to/from def_ids in the string rep.
@@ -61,7 +63,7 @@ fn enc_ty(w: io::writer, cx: @ctxt, t: ty::t) {
                 // Do not emit node ids that map to unexported names.  Those
                 // are not helpful.
                 if def_id.crate != local_crate ||
-                    cx.reachable.contains_key(def_id.node) {
+                    cx.reachable(def_id.node) {
                     w.write_char('"');
                     w.write_str(cx.ds(def_id));
                     w.write_char('|');