Move external-reachability checker to trans

Preparation for a fix for issue #2020

Author: marijnh

src/rustc/metadata/encoder.rs

@@ -29,8 +29,7 @@ export encode_def_id;
 type abbrev_map = map::hashmap<ty::t, tyencode::ty_abbrev>;
 
 type encode_ctxt = {ccx: @crate_ctxt,
-                    type_abbrevs: abbrev_map,
-                    reachable: reachable::map};
+                    type_abbrevs: abbrev_map};
 
 // Path table encoding
 fn encode_name(ebml_w: ebml::writer, name: str) {
@@ -97,7 +96,7 @@ 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 it: @item in module.items {
-        if !ecx.reachable.contains_key(it.id) ||
+        if !ecx.ccx.reachable.contains_key(it.id) ||
            !ast_util::is_exported(it.ident, module) { cont; }
         alt it.node {
           item_const(_, _) {
@@ -430,7 +429,7 @@ 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.reachable.contains_key(item.id) { ret; }
+    if !must_write && !ecx.ccx.reachable.contains_key(item.id) { ret; }
     *index += [{val: item.id, pos: ebml_w.writer.tell()}];
 
     alt item.node {
@@ -598,7 +597,7 @@ fn encode_info_for_native_item(ecx: @encode_ctxt, ebml_w: ebml::writer,
                                nitem: @native_item,
                                index: @mutable [entry<int>],
                                path: ast_map::path, abi: native_abi) {
-    if !ecx.reachable.contains_key(nitem.id) { ret; }
+    if !ecx.ccx.reachable.contains_key(nitem.id) { ret; }
     *index += [{val: nitem.id, pos: ebml_w.writer.tell()}];
 
     ebml_w.start_tag(tag_items_data_item);
@@ -861,12 +860,7 @@ fn encode_hash(ebml_w: ebml::writer, hash: str) {
 }
 
 fn encode_metadata(cx: @crate_ctxt, crate: @crate) -> [u8] {
-
-    let reachable = reachable::find_reachable(cx, crate.node.module);
-    let abbrevs = ty::new_ty_hash();
-    let ecx = @{ccx: cx,
-                type_abbrevs: abbrevs,
-                reachable: reachable};
+    let ecx = @{ccx: cx, type_abbrevs: ty::new_ty_hash()};
 
     let buf = io::mem_buffer();
     let buf_w = io::mem_buffer_writer(buf);

src/rustc/middle/trans/base.rs

@@ -4604,6 +4604,8 @@ fn trans_crate(sess: session::session, crate: @ast::crate, tcx: ty::ctxt,
     -> (ModuleRef, link::link_meta) {
     let sha = std::sha1::sha1();
     let link_meta = link::build_link_meta(sess, *crate, output, sha);
+    let reachable = reachable::find_reachable(crate.node.module, emap, tcx,
+                                              maps.method_map);
 
     // Append ".rc" to crate name as LLVM module identifier.
     //
@@ -4658,6 +4660,7 @@ fn trans_crate(sess: session::session, crate: @ast::crate, tcx: ty::ctxt,
           intrinsics: intrinsics,
           item_vals: int_hash::<ValueRef>(),
           exp_map: emap,
+          reachable: reachable,
           item_symbols: int_hash::<str>(),
           mutable main_fn: none::<ValueRef>,
           link_meta: link_meta,

src/rustc/middle/trans/common.rs

@@ -79,6 +79,7 @@ type crate_ctxt = {
      intrinsics: hashmap<str, ValueRef>,
      item_vals: hashmap<ast::node_id, ValueRef>,
      exp_map: resolve::exp_map,
+     reachable: reachable::map,
      item_symbols: hashmap<ast::node_id, str>,
      mutable main_fn: option<ValueRef>,
      link_meta: link::link_meta,

src/rustc/metadata/reachable.rs renamed to src/rustc/middle/trans/reachable.rs

@@ -5,7 +5,6 @@
 // makes all other generics or inline functions that it references
 // reachable as well.
 
-import middle::{resolve, ast_map, typeck};
 import syntax::ast::*;
 import syntax::{visit, ast_util};
 import syntax::ast_util::def_id_of_def;
@@ -16,13 +15,15 @@ export map, find_reachable;
 
 type map = std::map::hashmap<node_id, ()>;
 
-type ctx = {ccx: @middle::trans::common::crate_ctxt,
+type ctx = {exp_map: resolve::exp_map,
+            tcx: ty::ctxt,
+            method_map: typeck::method_map,
             rmap: map};
 
-fn find_reachable(ccx: @middle::trans::common::crate_ctxt, crate_mod: _mod)
-    -> map {
+fn find_reachable(crate_mod: _mod, exp_map: resolve::exp_map,
+                  tcx: ty::ctxt, method_map: typeck::method_map) -> map {
     let rmap = std::map::int_hash();
-    let cx = {ccx: ccx, rmap: rmap};
+    let cx = {exp_map: exp_map, tcx: tcx, method_map: method_map, rmap: rmap};
     traverse_public_mod(cx, crate_mod);
     traverse_all_resources(cx, crate_mod);
     rmap
@@ -50,14 +51,14 @@ fn traverse_exports(cx: ctx, vis: [@view_item]) -> bool {
 }
 
 fn traverse_export(cx: ctx, exp_id: node_id) {
-    option::may(cx.ccx.exp_map.find(exp_id)) {|defs|
+    option::may(cx.exp_map.find(exp_id)) {|defs|
         for def in defs { traverse_def_id(cx, def.id); }
     }
 }
 
 fn traverse_def_id(cx: ctx, did: def_id) {
     if did.crate != local_crate { ret; }
-    alt cx.ccx.tcx.items.get(did.node) {
+    alt cx.tcx.items.get(did.node) {
       ast_map::node_item(item, _) { traverse_public_item(cx, item); }
       ast_map::node_method(_, impl_id, _) { traverse_def_id(cx, impl_id); }
       ast_map::node_native_item(item, _, _) { cx.rmap.insert(item.id, ()); }
@@ -106,10 +107,10 @@ fn traverse_inline_body(cx: ctx, body: blk) {
     fn traverse_expr(e: @expr, cx: ctx, v: visit::vt<ctx>) {
         alt e.node {
           expr_path(_) {
-            traverse_def_id(cx, def_id_of_def(cx.ccx.tcx.def_map.get(e.id)));
+            traverse_def_id(cx, def_id_of_def(cx.tcx.def_map.get(e.id)));
           }
           expr_field(_, _, _) {
-            alt cx.ccx.maps.method_map.find(e.id) {
+            alt cx.method_map.find(e.id) {
               some(typeck::method_static(did)) { traverse_def_id(cx, did); }
               _ {}
             }

src/rustc/rustc.rc

@@ -28,6 +28,7 @@ mod middle {
         mod shape;
         mod debuginfo;
         mod type_use;
+        mod reachable;
     }
     mod ty;
     mod ast_map;
@@ -131,7 +132,6 @@ mod metadata {
     mod creader;
     mod cstore;
     mod csearch;
-    mod reachable;
 }
 
 mod driver {