From 44783f1db0bd1076d825b2b681c4220bbf97bbec Mon Sep 17 00:00:00 2001
From: Eduard-Mihai Burtescu <eddyb@lyken.rs>
Date: Mon, 13 Jun 2022 08:04:27 +0000
Subject: [PATCH] Revert "rustc_parse: work around instruction-counting
 non-determinism."

This reverts commit 521218ce88e12ed2960f619545cf22404cee8d1e.
---
 compiler/rustc_parse/src/lexer/mod.rs | 20 +++++++++++---------
 1 file changed, 11 insertions(+), 9 deletions(-)

diff --git a/compiler/rustc_parse/src/lexer/mod.rs b/compiler/rustc_parse/src/lexer/mod.rs
index f3b11e9b604..e9701ec2d7f 100644
--- a/compiler/rustc_parse/src/lexer/mod.rs
+++ b/compiler/rustc_parse/src/lexer/mod.rs
@@ -335,15 +335,17 @@ impl<'a> StringReader<'a> {
         comment_kind: CommentKind,
         doc_style: DocStyle,
     ) -> TokenKind {
-        for (idx, _) in content.match_indices('\r') {
-            self.err_span_(
-                content_start + BytePos(idx as u32),
-                content_start + BytePos(idx as u32 + 1),
-                match comment_kind {
-                    CommentKind::Line => "bare CR not allowed in doc-comment",
-                    CommentKind::Block => "bare CR not allowed in block doc-comment",
-                },
-            );
+        if content.contains('\r') {
+            for (idx, _) in content.char_indices().filter(|&(_, c)| c == '\r') {
+                self.err_span_(
+                    content_start + BytePos(idx as u32),
+                    content_start + BytePos(idx as u32 + 1),
+                    match comment_kind {
+                        CommentKind::Line => "bare CR not allowed in doc-comment",
+                        CommentKind::Block => "bare CR not allowed in block doc-comment",
+                    },
+                );
+            }
         }
 
         let attr_style = match doc_style {