Remove many shared pointers

Mostly just low-haning fruit, i.e. function arguments that were @ even
though & would work just as well.

Reduces librustc.so size by 200k when compiling without -O, by 100k when
compiling with -O.

src/librustc/driver/driver.rs

@@ -181,12 +181,12 @@ pub fn compile_rest(sess: Session,
 
     let time_passes = sess.time_passes();
 
-    let mut crate_opt = curr;
+    let mut crate = curr.unwrap();
 
     if phases.from == cu_parse || phases.from == cu_everything {
 
         *sess.building_library = session::building_library(
-            sess.opts.crate_type, crate_opt.unwrap(), sess.opts.test);
+            sess.opts.crate_type, crate, sess.opts.test);
 
         // strip before expansion to allow macros to depend on
         // configuration variables e.g/ in
@@ -195,27 +195,25 @@ pub fn compile_rest(sess: Session,
         //   mod bar { macro_rules! baz!(() => {{}}) }
         //
         // baz! should not use this definition unless foo is enabled.
-        crate_opt = Some(time(time_passes, ~"configuration 1", ||
-                     front::config::strip_unconfigured_items(crate_opt.unwrap())));
+        crate = time(time_passes, ~"configuration 1", ||
+                     front::config::strip_unconfigured_items(crate));
 
-        crate_opt = Some(time(time_passes, ~"expansion", ||
+        crate = time(time_passes, ~"expansion", ||
                      syntax::ext::expand::expand_crate(sess.parse_sess, copy cfg,
-                                                       crate_opt.unwrap())));
+                                                       crate));
 
         // strip again, in case expansion added anything with a #[cfg].
-        crate_opt = Some(time(time_passes, ~"configuration 2", ||
-                     front::config::strip_unconfigured_items(crate_opt.unwrap())));
+        crate = time(time_passes, ~"configuration 2", ||
+                     front::config::strip_unconfigured_items(crate));
 
-        crate_opt = Some(time(time_passes, ~"maybe building test harness", ||
-                     front::test::modify_for_testing(sess, crate_opt.unwrap())));
+        crate = time(time_passes, ~"maybe building test harness", ||
+                     front::test::modify_for_testing(sess, crate));
     }
 
-    if phases.to == cu_expand { return (crate_opt, None); }
+    if phases.to == cu_expand { return (Some(crate), None); }
 
     assert!(phases.from != cu_no_trans);
 
-    let mut crate = crate_opt.unwrap();
-
     let (llcx, llmod, link_meta) = {
         crate = time(time_passes, ~"extra injection", ||
                      front::std_inject::maybe_inject_libstd_ref(sess, crate));

src/librustc/driver/session.rs

@@ -349,7 +349,7 @@ pub fn expect<T:Copy>(sess: Session,
 }
 
 pub fn building_library(req_crate_type: crate_type,
-                        crate: @ast::crate,
+                        crate: &ast::crate,
                         testing: bool) -> bool {
     match req_crate_type {
       bin_crate => false,

src/librustc/front/config.rs

@@ -24,11 +24,11 @@ struct Context {
 // any items that do not belong in the current configuration
 pub fn strip_unconfigured_items(crate: @ast::crate) -> @ast::crate {
     do strip_items(crate) |attrs| {
-        in_cfg(/*bad*/copy crate.node.config, attrs)
+        in_cfg(crate.node.config, attrs)
     }
 }
 
-pub fn strip_items(crate: @ast::crate, in_cfg: in_cfg_pred)
+pub fn strip_items(crate: &ast::crate, in_cfg: in_cfg_pred)
     -> @ast::crate {
 
     let ctxt = @Context { in_cfg: in_cfg };
@@ -44,8 +44,7 @@ pub fn strip_items(crate: @ast::crate, in_cfg: in_cfg_pred)
           .. *fold::default_ast_fold()};
 
     let fold = fold::make_fold(precursor);
-    let res = @fold.fold_crate(&*crate);
-    return res;
+    @fold.fold_crate(crate)
 }
 
 fn filter_item(cx: @Context, item: @ast::item) ->
@@ -183,12 +182,12 @@ fn trait_method_in_cfg(cx: @Context, meth: &ast::trait_method) -> bool {
 
 // Determine if an item should be translated in the current crate
 // configuration based on the item's attributes
-fn in_cfg(cfg: ast::crate_cfg, attrs: ~[ast::attribute]) -> bool {
+fn in_cfg(cfg: &[@ast::meta_item], attrs: &[ast::attribute]) -> bool {
     metas_in_cfg(cfg, attr::attr_metas(attrs))
 }
 
-pub fn metas_in_cfg(cfg: ast::crate_cfg,
-                    metas: ~[@ast::meta_item]) -> bool {
+pub fn metas_in_cfg(cfg: &[@ast::meta_item],
+                    metas: &[@ast::meta_item]) -> bool {
     // The "cfg" attributes on the item
     let cfg_metas = attr::find_meta_items_by_name(metas, "cfg");
 

src/librustc/front/std_inject.rs

@@ -30,11 +30,11 @@ pub fn maybe_inject_libstd_ref(sess: Session, crate: @ast::crate)
     }
 }
 
-fn use_std(crate: @ast::crate) -> bool {
+fn use_std(crate: &ast::crate) -> bool {
     !attr::attrs_contains_name(crate.node.attrs, "no_std")
 }
 
-fn inject_libstd_ref(sess: Session, crate: @ast::crate) -> @ast::crate {
+fn inject_libstd_ref(sess: Session, crate: &ast::crate) -> @ast::crate {
     fn spanned<T:Copy>(x: T) -> codemap::spanned<T> {
         codemap::spanned { node: x, span: dummy_sp() }
     }

src/librustc/front/test.rs

@@ -92,7 +92,7 @@ fn generate_test_harness(sess: session::Session,
     return res;
 }
 
-fn strip_test_functions(crate: @ast::crate) -> @ast::crate {
+fn strip_test_functions(crate: &ast::crate) -> @ast::crate {
     // When not compiling with --test we should not compile the
     // #[test] functions
     do config::strip_items(crate) |attrs| {

src/librustc/metadata/creader.rs

@@ -18,7 +18,6 @@ use metadata::filesearch::FileSearch;
 use metadata::loader;
 
 use core::hashmap::HashMap;
-use core::vec;
 use syntax::attr;
 use syntax::codemap::{span, dummy_sp};
 use syntax::diagnostic::span_handler;
@@ -30,7 +29,7 @@ use syntax::ast;
 // Traverses an AST, reading all the information about use'd crates and extern
 // libraries necessary for later resolving, typechecking, linking, etc.
 pub fn read_crates(diag: @span_handler,
-                   crate: @ast::crate,
+                   crate: &ast::crate,
                    cstore: @mut cstore::CStore,
                    filesearch: @FileSearch,
                    os: loader::os,
@@ -53,8 +52,8 @@ pub fn read_crates(diag: @span_handler,
             .. *visit::default_simple_visitor()});
     visit_crate(e, crate);
     visit::visit_crate(crate, ((), v));
-    dump_crates(e.crate_cache);
-    warn_if_multiple_versions(e, diag, e.crate_cache);
+    dump_crates(*e.crate_cache);
+    warn_if_multiple_versions(e, diag, *e.crate_cache);
 }
 
 struct cache_entry {
@@ -64,7 +63,7 @@ struct cache_entry {
     metas: @~[@ast::meta_item]
 }
 
-fn dump_crates(crate_cache: @mut ~[cache_entry]) {
+fn dump_crates(crate_cache: &[cache_entry]) {
     debug!("resolved crates:");
     for crate_cache.iter().advance |entry| {
         debug!("cnum: %?", entry.cnum);
@@ -75,11 +74,9 @@ fn dump_crates(crate_cache: @mut ~[cache_entry]) {
 
 fn warn_if_multiple_versions(e: @mut Env,
                              diag: @span_handler,
-                             crate_cache: @mut ~[cache_entry]) {
+                             crate_cache: &[cache_entry]) {
     use core::either::*;
 
-    let crate_cache = &mut *crate_cache;
-
     if crate_cache.len() != 0u {
         let name = loader::crate_name_from_metas(
             *crate_cache[crate_cache.len() - 1].metas
@@ -111,7 +108,7 @@ fn warn_if_multiple_versions(e: @mut Env,
             }
         }
 
-        warn_if_multiple_versions(e, diag, @mut non_matches);
+        warn_if_multiple_versions(e, diag, non_matches);
     }
 }
 
@@ -126,7 +123,7 @@ struct Env {
     intr: @ident_interner
 }
 
-fn visit_crate(e: @mut Env, c: &ast::crate) {
+fn visit_crate(e: &Env, c: &ast::crate) {
     let cstore = e.cstore;
     let link_args = attr::find_attrs_by_name(c.node.attrs, "link_args");
 
@@ -152,7 +149,7 @@ fn visit_view_item(e: @mut Env, i: @ast::view_item) {
     }
 }
 
-fn visit_item(e: @mut Env, i: @ast::item) {
+fn visit_item(e: &Env, i: @ast::item) {
     match i.node {
       ast::item_foreign_mod(ref fm) => {
         if fm.abis.is_rust() || fm.abis.is_intrinsic() {
@@ -204,26 +201,25 @@ fn visit_item(e: @mut Env, i: @ast::item) {
     }
 }
 
-fn metas_with(ident: @str, key: @str, metas: ~[@ast::meta_item])
+fn metas_with(ident: @str, key: @str, mut metas: ~[@ast::meta_item])
     -> ~[@ast::meta_item] {
     let name_items = attr::find_meta_items_by_name(metas, key);
     if name_items.is_empty() {
-        vec::append_one(metas, attr::mk_name_value_item_str(key, ident))
-    } else {
-        metas
+        metas.push(attr::mk_name_value_item_str(key, ident));
     }
+    metas
 }
 
 fn metas_with_ident(ident: @str, metas: ~[@ast::meta_item])
     -> ~[@ast::meta_item] {
     metas_with(ident, @"name", metas)
 }
 
-fn existing_match(e: @mut Env, metas: &[@ast::meta_item], hash: @str)
+fn existing_match(e: &Env, metas: &[@ast::meta_item], hash: &str)
                -> Option<int> {
     for e.crate_cache.iter().advance |c| {
         if loader::metadata_matches(*c.metas, metas)
-            && (hash.is_empty() || c.hash == hash) {
+            && (hash.is_empty() || c.hash.as_slice() == hash) {
             return Some(c.cnum);
         }
     }

src/librustc/middle/borrowck/mod.rs

@@ -58,7 +58,7 @@ pub fn check_crate(
     moves_map: moves::MovesMap,
     moved_variables_set: moves::MovedVariablesSet,
     capture_map: moves::CaptureMap,
-    crate: @ast::crate) -> (root_map, write_guard_map)
+    crate: &ast::crate) -> (root_map, write_guard_map)
 {
     let bccx = @BorrowckCtxt {
         tcx: tcx,
@@ -507,7 +507,7 @@ impl BorrowckCtxt {
     pub fn report_use_of_moved_value(&self,
                                      use_span: span,
                                      use_kind: MovedValueUseKind,
-                                     lp: @LoanPath,
+                                     lp: &LoanPath,
                                      move: &move_data::Move,
                                      moved_lp: @LoanPath) {
         let verb = match use_kind {
@@ -570,7 +570,7 @@ impl BorrowckCtxt {
 
     pub fn report_reassigned_immutable_variable(&self,
                                                 span: span,
-                                                lp: @LoanPath,
+                                                lp: &LoanPath,
                                                 assign:
                                                 &move_data::Assignment) {
         self.tcx.sess.span_err(

src/librustc/middle/check_const.rs

@@ -21,7 +21,7 @@ use syntax::codemap;
 use syntax::{visit, ast_util, ast_map};
 
 pub fn check_crate(sess: Session,
-                   crate: @crate,
+                   crate: &crate,
                    ast_map: ast_map::map,
                    def_map: resolve::DefMap,
                    method_map: typeck::method_map,

src/librustc/middle/check_loop.rs

@@ -19,7 +19,7 @@ pub struct Context {
     can_ret: bool
 }
 
-pub fn check_crate(tcx: ty::ctxt, crate: @crate) {
+pub fn check_crate(tcx: ty::ctxt, crate: &crate) {
     visit::visit_crate(crate,
                        (Context { in_loop: false, can_ret: true },
                        visit::mk_vt(@visit::Visitor {