make region-param-def encoding more DRY

we used to have two separate routines, one in tyencode/tydecode, and one
in encode/decode.

Author: nikomatsakis

src/librustc_metadata/decoder.rs

@@ -1662,31 +1662,12 @@ fn doc_generics<'a, 'tcx>(base_doc: rbml::Doc,
     }
 
     let mut regions = subst::VecPerParamSpace::empty();
-    for rp_doc in reader::tagged_docs(doc, tag_region_param_def) {
-        let ident_str_doc = reader::get_doc(rp_doc,
-                                            tag_region_param_def_ident);
-        let name = item_name(&token::get_ident_interner(), ident_str_doc);
-        let def_id_doc = reader::get_doc(rp_doc,
-                                         tag_region_param_def_def_id);
-        let def_id = translated_def_id(cdata, def_id_doc);
-
-        let doc = reader::get_doc(rp_doc, tag_region_param_def_space);
-        let space = subst::ParamSpace::from_uint(reader::doc_as_u64(doc) as usize);
-
-        let doc = reader::get_doc(rp_doc, tag_region_param_def_index);
-        let index = reader::doc_as_u64(doc) as u32;
-
-        let bounds = reader::tagged_docs(rp_doc, tag_items_data_region).map(|p| {
+    for p in reader::tagged_docs(doc, tag_region_param_def) {
+        let bd =
             TyDecoder::with_doc(tcx, cdata.cnum, p,
                                 &mut |did| translate_def_id(cdata, did))
-            .parse_region()
-        }).collect();
-
-        regions.push(space, ty::RegionParameterDef { name: name,
-                                                     def_id: def_id,
-                                                     space: space,
-                                                     index: index,
-                                                     bounds: bounds });
+            .parse_region_param_def();
+        regions.push(bd.space, bd);
     }
 
     ty::Generics { types: types, regions: regions }

src/librustc_metadata/encoder.rs

@@ -203,15 +203,6 @@ fn encode_type<'a, 'tcx>(ecx: &EncodeContext<'a, 'tcx>,
     rbml_w.end_tag();
 }
 
-fn encode_region(ecx: &EncodeContext,
-                 rbml_w: &mut Encoder,
-                 r: ty::Region) {
-    rbml_w.start_tag(tag_items_data_region);
-    tyencode::enc_region(rbml_w.writer, &ecx.ty_str_ctxt(), r);
-    rbml_w.mark_stable_position();
-    rbml_w.end_tag();
-}
-
 fn encode_disr_val(_: &EncodeContext,
                    rbml_w: &mut Encoder,
                    disr_val: ty::Disr) {
@@ -535,24 +526,8 @@ fn encode_generics<'a, 'tcx>(rbml_w: &mut Encoder,
     // Region parameters
     for param in &generics.regions {
         rbml_w.start_tag(tag_region_param_def);
-
-        rbml_w.start_tag(tag_region_param_def_ident);
-        encode_name(rbml_w, param.name);
-        rbml_w.end_tag();
-
-        rbml_w.wr_tagged_u64(tag_region_param_def_def_id,
-                             def_to_u64(param.def_id));
-
-        rbml_w.wr_tagged_u64(tag_region_param_def_space,
-                             param.space.to_uint() as u64);
-
-        rbml_w.wr_tagged_u64(tag_region_param_def_index,
-                             param.index as u64);
-
-        for &bound_region in &param.bounds {
-            encode_region(ecx, rbml_w, bound_region);
-        }
-
+        tyencode::enc_region_param_def(rbml_w.writer, &ecx.ty_str_ctxt(), param);
+        rbml_w.mark_stable_position();
         rbml_w.end_tag();
     }
 

src/librustc_metadata/tydecode.rs

@@ -636,7 +636,7 @@ impl<'a,'tcx> TyDecoder<'a,'tcx> {
             def_id: def_id,
             space: space,
             index: index,
-            bounds: bounds
+            bounds: bounds,
         }
     }