Perf improvements for debuginfo

debugperf.diff

diff --git a/src/comp/middle/debuginfo.rs b/src/comp/middle/debuginfo.rs
index 4d81b68..0ab1a8e 100644
--- a/src/comp/middle/debuginfo.rs
+++ b/src/comp/middle/debuginfo.rs
@@ -101,7 +101,7 @@ type metadata<T> = {node: ValueRef, data: T};
 
 type file_md = {path: str};
 type compile_unit_md = {path: str};
-type subprogram_md = {path: str};
+type subprogram_md = {id: ast::node_id};
 type local_var_md = {id: ast::node_id};
 type tydesc_md = {hash: uint};
 type block_md = {start: codemap::loc, end: codemap::loc};
@@ -241,12 +241,12 @@ fn create_block(cx: @block_ctxt) -> @metadata<block_md> {
     let end = codemap::lookup_char_pos(bcx_ccx(cx).sess.codemap,
                                        sp.hi);
     let tg = LexicalBlockTag;
-    alt cached_metadata::<@metadata<block_md>>(
+    /*alt cached_metadata::<@metadata<block_md>>(
         cache, tg,
         {|md| start == md.data.start && end == md.data.end}) {
       option::some(md) { ret md; }
       option::none {}
-    }
+    }*/
 
     let parent = alt cx.parent {
       parent_none { create_function(cx.fcx).node }
@@ -266,7 +266,7 @@ fn create_block(cx: @block_ctxt) -> @metadata<block_md> {
                  ];
     let val = llmdnode(lldata);
     let mdval = @{node: val, data: {start: start, end: end}};
-    update_cache(cache, tg, block_metadata(mdval));
+    //update_cache(cache, tg, block_metadata(mdval));
     ret mdval;
 }
 
@@ -764,16 +764,15 @@ fn create_function(fcx: @fn_ctxt) -> @metadata<subprogram_md> {
     log(debug, ident);
     log(debug, id);
 
-    let path = str::connect(fcx.lcx.path + [ident], "::");
-
     let cache = get_cache(cx);
     alt cached_metadata::<@metadata<subprogram_md>>(
-        cache, SubprogramTag, {|md| md.data.path == path &&
-                                    /*md.data.path == ??*/ true}) {
+        cache, SubprogramTag, {|md| md.data.id == id}) {
       option::some(md) { ret md; }
       option::none {}
     }
 
+    let path = str::connect(fcx.lcx.path + [ident], "::");
+
     let loc = codemap::lookup_char_pos(cx.sess.codemap,
                                        sp.lo);
     let file_node = create_file(cx, loc.filename).node;
@@ -815,7 +814,7 @@ fn create_function(fcx: @fn_ctxt) -> @metadata<subprogram_md> {
                       ];
     let val = llmdnode(fn_metadata);
     add_named_metadata(cx, "llvm.dbg.sp", val);
-    let mdval = @{node: val, data: {path: path}};
+    let mdval = @{node: val, data: {id: id}};
     update_cache(cache, SubprogramTag, subprogram_metadata(mdval));
     ret mdval;
 }