diff --git a/llvm/utils/UpdateTestChecks/common.py b/llvm/utils/UpdateTestChecks/common.py
--- a/llvm/utils/UpdateTestChecks/common.py
+++ b/llvm/utils/UpdateTestChecks/common.py
@@ -68,6 +68,8 @@
 SCRUB_LEADING_WHITESPACE_RE = re.compile(r'^(\s+)')
 SCRUB_WHITESPACE_RE = re.compile(r'(?!^(|  \w))[ \t]+', flags=re.M)
 SCRUB_TRAILING_WHITESPACE_RE = re.compile(r'[ \t]+$', flags=re.M)
+SCRUB_TRAILING_WHITESPACE_TEST_RE = SCRUB_TRAILING_WHITESPACE_RE
+SCRUB_TRAILING_WHITESPACE_AND_ATTRIBUTES_RE = re.compile(r'([ \t]|(#[0-9]+))+$', flags=re.M)
 SCRUB_KILL_COMMENT_RE = re.compile(r'^ *#+ +kill:.*\n')
 SCRUB_LOOP_COMMENT_RE = re.compile(
     r'# =>This Inner Loop Header:.*|# in Loop:.*', flags=re.M)
@@ -90,7 +92,7 @@
   # Expand the tabs used for indentation.
   body = string.expandtabs(body, 2)
   # Strip trailing whitespace.
-  body = SCRUB_TRAILING_WHITESPACE_RE.sub(r'', body)
+  body = SCRUB_TRAILING_WHITESPACE_TEST_RE.sub(r'', body)
   return body
 
 def do_scrub(body, scrubber, scrubber_args, extra):
diff --git a/llvm/utils/update_test_checks.py b/llvm/utils/update_test_checks.py
--- a/llvm/utils/update_test_checks.py
+++ b/llvm/utils/update_test_checks.py
@@ -68,6 +68,8 @@
                       help='Do not scrub IR names')
   parser.add_argument('--function-signature', action='store_true',
                       help='Keep function signature information around for the check line')
+  parser.add_argument('--scrub-attributes', action='store_true',
+                      help='Remove attribute annotations (#0) from the end of check line')
   parser.add_argument('tests', nargs='+')
   args = parser.parse_args()
 
@@ -103,6 +105,12 @@
         common.warn("Skipping test which isn't autogenerated: " + test)
         continue
 
+    # If requested we scrub trailing attribute annotations, e.g., '#0', together with whitespaces
+    if args.scrub_attributes:
+      common.SCRUB_TRAILING_WHITESPACE_TEST_RE = common.SCRUB_TRAILING_WHITESPACE_AND_ATTRIBUTES_RE
+    else:
+      common.SCRUB_TRAILING_WHITESPACE_TEST_RE = common.SCRUB_TRAILING_WHITESPACE_RE
+
     raw_lines = [m.group(1)
                  for m in [common.RUN_LINE_RE.match(l) for l in input_lines] if m]
     run_lines = [raw_lines[0]] if len(raw_lines) > 0 else []