auto merge of #8420 : blake2-ppc/rust/shrink-token, r=cmr

`enum Token` was 192 bytes (64-bit), as pointed out by pnkfelix; the only
bloating variant being `INTERPOLATED(nonterminal)`.

Updating `enum nonterminal` to use ~ where variants included big types,
shrunk size_of(Token) to 32 bytes (64-bit).

I am unsure if the `nt_ident` variant should have an indirection, with
ast::ident being only 16 bytes (64-bit), but without this, enum Token
would be 40 bytes.

A dumb benchmark says that compilation time is unchanged, while peak
memory usage for compiling std.rs is down 3%

Before::

    $ time ./x86_64-unknown-linux-gnu/stage1/bin/rustc --cfg stage1 src/libstd/std.rs
    19.00user 0.39system 0:19.41elapsed 99%CPU (0avgtext+0avgdata 627820maxresident)k
    0inputs+28896outputs (0major+228665minor)pagefaults 0swaps
    $ time ./x86_64-unknown-linux-gnu/stage1/bin/rustc -O --cfg stage1 src/libstd/std.rs
    31.64user 0.34system 0:32.02elapsed 99%CPU (0avgtext+0avgdata 629876maxresident)k
    0inputs+22432outputs (0major+229411minor)pagefaults 0swaps

After::

    $ time ./x86_64-unknown-linux-gnu/stage1/bin/rustc --cfg stage1 src/libstd/std.rs
    19.07user 0.45system 0:19.55elapsed 99%CPU (0avgtext+0avgdata 609384maxresident)k
    0inputs+28896outputs (0major+221997minor)pagefaults 0swaps

    $ time ./x86_64-unknown-linux-gnu/stage1/bin/rustc -O --cfg stage1 src/libstd/std.rs
    31.90user 0.34system 0:32.28elapsed 99%CPU (0avgtext+0avgdata 612080maxresident)k
    0inputs+22432outputs (0major+223726minor)pagefaults 0swaps

2 files changed, 5 insertions, 5 deletions

diff --git a/src/libsyntax/ext/tt/macro_parser.rs b/src/libsyntax/ext/tt/macro_parser.rs
index 918949113ad..29963a7b461 100644
--- a/src/libsyntax/ext/tt/macro_parser.rs
+++ b/src/libsyntax/ext/tt/macro_parser.rs
@@ -419,18 +419,18 @@ pub fn parse_nt(p: &Parser, name: &str) -> nonterminal {
         Some(i) => token::nt_item(i),
         None => p.fatal("expected an item keyword")
       },
-      "block" => token::nt_block(p.parse_block()),
+      "block" => token::nt_block(~p.parse_block()),
       "stmt" => token::nt_stmt(p.parse_stmt(~[])),
       "pat" => token::nt_pat(p.parse_pat()),
       "expr" => token::nt_expr(p.parse_expr()),
-      "ty" => token::nt_ty(p.parse_ty(false /* no need to disambiguate*/)),
+      "ty" => token::nt_ty(~p.parse_ty(false /* no need to disambiguate*/)),
       // this could be handled like a token, since it is one
       "ident" => match *p.token {
-        token::IDENT(sn,b) => { p.bump(); token::nt_ident(sn,b) }
+        token::IDENT(sn,b) => { p.bump(); token::nt_ident(~sn,b) }
         _ => p.fatal(~"expected ident, found "
                      + token::to_str(get_ident_interner(), p.token))
       },
-      "path" => token::nt_path(p.parse_path_with_tps(false)),
+      "path" => token::nt_path(~p.parse_path_with_tps(false)),
       "attr" => token::nt_attr(@p.parse_attribute(false)),
       "tt" => {
         *p.quote_depth += 1u; //but in theory, non-quoted tts might be useful
diff --git a/src/libsyntax/ext/tt/transcribe.rs b/src/libsyntax/ext/tt/transcribe.rs
index 16019b21448..9d3e916b500 100644
--- a/src/libsyntax/ext/tt/transcribe.rs
+++ b/src/libsyntax/ext/tt/transcribe.rs
@@ -279,7 +279,7 @@ pub fn tt_next_token(r: &mut TtReader) -> TokenAndSpan {
               /* sidestep the interpolation tricks for ident because
               (a) idents can be in lots of places, so it'd be a pain
               (b) we actually can, since it's a token. */
-              matched_nonterminal(nt_ident(sn,b)) => {
+              matched_nonterminal(nt_ident(~sn,b)) => {
                 r.cur_span = sp; r.cur_tok = IDENT(sn,b);
                 r.stack.idx += 1u;
                 return ret_val;