Order rules in quote_token! and quote_token_spanned! by frequency.

This reduces `cargo check` times by 4-9% on a few crates that use `quote!` heavily.
dtolnay · Mar 17, 2022 · fad6995 · fad6995
1 parent 278057d
commit fad6995
Showing 1 changed file with 61 additions and 56 deletions.
diff --git a/src/lib.rs b/src/lib.rs
@@ -859,9 +859,21 @@ macro_rules! quote_token_with_context_spanned {
     };
 }
 
+// These rules are ordered by approximate token frequency, at least for the
+// first 10 or so, to improve compile times. Having `ident` first is by far the
+// most important, because it's typically 2-3x more common than the next most
+// common token.
 #[macro_export]
 #[doc(hidden)]
 macro_rules! quote_token {
+    ($tokens:ident $ident:ident) => {
+        $crate::__private::push_ident(&mut $tokens, stringify!($ident));
+    };
+
+    ($tokens:ident ::) => {
+        $crate::__private::push_colon2(&mut $tokens);
+    };
+
     ($tokens:ident ( $($inner:tt)* )) => {
         $crate::__private::push_group(
             &mut $tokens,
@@ -886,6 +898,26 @@ macro_rules! quote_token {
         );
     };
 
+    ($tokens:ident #) => {
+        $crate::__private::push_pound(&mut $tokens);
+    };
+
+    ($tokens:ident ,) => {
+        $crate::__private::push_comma(&mut $tokens);
+    };
+
+    ($tokens:ident .) => {
+        $crate::__private::push_dot(&mut $tokens);
+    };
+
+    ($tokens:ident ;) => {
+        $crate::__private::push_semi(&mut $tokens);
+    };
+
+    ($tokens:ident :) => {
+        $crate::__private::push_colon(&mut $tokens);
+    };
+
     ($tokens:ident +) => {
         $crate::__private::push_add(&mut $tokens);
     };
@@ -922,18 +954,6 @@ macro_rules! quote_token {
         $crate::__private::push_caret_eq(&mut $tokens);
     };
 
-    ($tokens:ident :) => {
-        $crate::__private::push_colon(&mut $tokens);
-    };
-
-    ($tokens:ident ::) => {
-        $crate::__private::push_colon2(&mut $tokens);
-    };
-
-    ($tokens:ident ,) => {
-        $crate::__private::push_comma(&mut $tokens);
-    };
-
     ($tokens:ident /) => {
         $crate::__private::push_div(&mut $tokens);
     };
@@ -942,10 +962,6 @@ macro_rules! quote_token {
         $crate::__private::push_div_eq(&mut $tokens);
     };
 
-    ($tokens:ident .) => {
-        $crate::__private::push_dot(&mut $tokens);
-    };
-
     ($tokens:ident ..) => {
         $crate::__private::push_dot2(&mut $tokens);
     };
@@ -1002,10 +1018,6 @@ macro_rules! quote_token {
         $crate::__private::push_or_or(&mut $tokens);
     };
 
-    ($tokens:ident #) => {
-        $crate::__private::push_pound(&mut $tokens);
-    };
-
     ($tokens:ident ?) => {
         $crate::__private::push_question(&mut $tokens);
     };
@@ -1030,10 +1042,6 @@ macro_rules! quote_token {
         $crate::__private::push_fat_arrow(&mut $tokens);
     };
 
-    ($tokens:ident ;) => {
-        $crate::__private::push_semi(&mut $tokens);
-    };
-
     ($tokens:ident <<) => {
         $crate::__private::push_shl(&mut $tokens);
     };
@@ -1062,10 +1070,6 @@ macro_rules! quote_token {
         $crate::__private::push_sub_eq(&mut $tokens);
     };
 
-    ($tokens:ident $ident:ident) => {
-        $crate::__private::push_ident(&mut $tokens, stringify!($ident));
-    };
-
     ($tokens:ident $lifetime:lifetime) => {
         $crate::__private::push_lifetime(&mut $tokens, stringify!($lifetime));
     };
@@ -1079,9 +1083,18 @@ macro_rules! quote_token {
     };
 }
 
+// See the comment above `quote_token!` about the rule ordering.
 #[macro_export]
 #[doc(hidden)]
 macro_rules! quote_token_spanned {
+    ($tokens:ident $span:ident $ident:ident) => {
+        $crate::__private::push_ident_spanned(&mut $tokens, $span, stringify!($ident));
+    };
+
+    ($tokens:ident $span:ident ::) => {
+        $crate::__private::push_colon2_spanned(&mut $tokens, $span);
+    };
+
     ($tokens:ident $span:ident ( $($inner:tt)* )) => {
         $crate::__private::push_group_spanned(
             &mut $tokens,
@@ -1109,6 +1122,26 @@ macro_rules! quote_token_spanned {
         );
     };
 
+    ($tokens:ident $span:ident #) => {
+        $crate::__private::push_pound_spanned(&mut $tokens, $span);
+    };
+
+    ($tokens:ident $span:ident ,) => {
+        $crate::__private::push_comma_spanned(&mut $tokens, $span);
+    };
+
+    ($tokens:ident $span:ident .) => {
+        $crate::__private::push_dot_spanned(&mut $tokens, $span);
+    };
+
+    ($tokens:ident $span:ident ;) => {
+        $crate::__private::push_semi_spanned(&mut $tokens, $span);
+    };
+
+    ($tokens:ident $span:ident :) => {
+        $crate::__private::push_colon_spanned(&mut $tokens, $span);
+    };
+
     ($tokens:ident $span:ident +) => {
         $crate::__private::push_add_spanned(&mut $tokens, $span);
     };
@@ -1145,18 +1178,6 @@ macro_rules! quote_token_spanned {
         $crate::__private::push_caret_eq_spanned(&mut $tokens, $span);
     };
 
-    ($tokens:ident $span:ident :) => {
-        $crate::__private::push_colon_spanned(&mut $tokens, $span);
-    };
-
-    ($tokens:ident $span:ident ::) => {
-        $crate::__private::push_colon2_spanned(&mut $tokens, $span);
-    };
-
-    ($tokens:ident $span:ident ,) => {
-        $crate::__private::push_comma_spanned(&mut $tokens, $span);
-    };
-
     ($tokens:ident $span:ident /) => {
         $crate::__private::push_div_spanned(&mut $tokens, $span);
     };
@@ -1165,10 +1186,6 @@ macro_rules! quote_token_spanned {
         $crate::__private::push_div_eq_spanned(&mut $tokens, $span);
     };
 
-    ($tokens:ident $span:ident .) => {
-        $crate::__private::push_dot_spanned(&mut $tokens, $span);
-    };
-
     ($tokens:ident $span:ident ..) => {
         $crate::__private::push_dot2_spanned(&mut $tokens, $span);
     };
@@ -1225,10 +1242,6 @@ macro_rules! quote_token_spanned {
         $crate::__private::push_or_or_spanned(&mut $tokens, $span);
     };
 
-    ($tokens:ident $span:ident #) => {
-        $crate::__private::push_pound_spanned(&mut $tokens, $span);
-    };
-
     ($tokens:ident $span:ident ?) => {
         $crate::__private::push_question_spanned(&mut $tokens, $span);
     };
@@ -1253,10 +1266,6 @@ macro_rules! quote_token_spanned {
         $crate::__private::push_fat_arrow_spanned(&mut $tokens, $span);
     };
 
-    ($tokens:ident $span:ident ;) => {
-        $crate::__private::push_semi_spanned(&mut $tokens, $span);
-    };
-
     ($tokens:ident $span:ident <<) => {
         $crate::__private::push_shl_spanned(&mut $tokens, $span);
     };
@@ -1285,10 +1294,6 @@ macro_rules! quote_token_spanned {
         $crate::__private::push_sub_eq_spanned(&mut $tokens, $span);
     };
 
-    ($tokens:ident $span:ident $ident:ident) => {
-        $crate::__private::push_ident_spanned(&mut $tokens, $span, stringify!($ident));
-    };
-
     ($tokens:ident $span:ident $lifetime:lifetime) => {
         $crate::__private::push_lifetime_spanned(&mut $tokens, $span, stringify!($lifetime));
     };