inline parse session getter functions for proc-macro-server performance

Author: mystor

compiler/rustc_expand/src/base.rs

@@ -1011,6 +1011,7 @@ impl<'a> ExtCtxt<'a> {
     pub fn source_map(&self) -> &'a SourceMap {
         self.sess.parse_sess.source_map()
     }
+    #[inline]
     pub fn parse_sess(&self) -> &'a ParseSess {
         &self.sess.parse_sess
     }

compiler/rustc_expand/src/proc_macro_server.rs

@@ -377,6 +377,7 @@ impl<'a, 'b> Rustc<'a, 'b> {
         }
     }
 
+    #[inline]
     fn sess(&self) -> &ParseSess {
         self.ecx.parse_sess()
     }