[Utils] Allow update_test_checks to scrub attribute annotations

[jdoerfert]

Summary

Attribute annotations, e.g., #0, are not useful on their own. This
patch adds a flag to update_test_checks to scrub them.

[jdoerfert]

Make the decision per test (in preperation of D69701)

[lebedev.ri]

Now that i believe there's some testing infra for these utils, add/update tests for this?

[jdoerfert]

Add a regression test

[merge_guards_bot]

Unit tests: unknown.

clang-tidy: unknown.

clang-format: unknown.

Build artifacts: diff.json, console-log.txt

[lebedev.ri]

This is opt-in so should be ok.

[arichardson]

Could you also make this change to update_cc_test_checks.py?

This code could move to common and we add a generates_ir flag to common.parse_commandline_args(parser). If that flag is set, parse_commandline_args adds the --function-signature and --scrub-attributes command line option and performs the SCRUB_TRAILING_WHITESPACE_TEST_RE -> SCRUB_TRAILING_WHITESPACE_AND_ATTRIBUTES_RE subsitituion?
If it's in common there should be no need for a separate update_cc_test_checks test (however, it probably makes sense to wait until D71565 has landed to avoid regresssions).

[jdoerfert]

In D68851#1799748, @arichardson wrote:

Could you also make this change to update_cc_test_checks.py?

This code could move to common and we add a generates_ir flag to common.parse_commandline_args(parser). If that flag is set, parse_commandline_args adds the --function-signature and --scrub-attributes command line option and performs the SCRUB_TRAILING_WHITESPACE_TEST_RE -> SCRUB_TRAILING_WHITESPACE_AND_ATTRIBUTES_RE subsitituion?
If it's in common there should be no need for a separate update_cc_test_checks test (however, it probably makes sense to wait until D71565 has landed to avoid regresssions).

I'm in favor of this happening and I can put it on my list. Though, if you want me to do this it will take some time.

llvm/utils/UpdateTestChecks/common.py

 IR_FUNCTION_RE = re.compile('^\s*define\s+(?:internal\s+)?[^@]*@(\w+)\s*\(')
 TRIPLE_IR_RE = re.compile(r'^\s*target\s+triple\s*=\s*"([^"]+)"$')
 TRIPLE_ARG_RE = re.compile(r'-mtriple[= ]([^ ]+)')
 MARCH_ARG_RE = re.compile(r'-march[= ]([^ ]+)')
 
 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]+$', flags=re.M)
+SCRUB_TRAILING_WHITESPACE_AND_ATTRIBUTES_RE = re.compile(r'([ \t]|(#[0-9]+))+$', 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)
 
 
 def error(msg, test_file=None):
   if test_file:
     msg = '{}: {}'.format(msg, test_file)

llvm/utils/update_test_checks.py

def main():
   parser.add_argument(
       '--function', help='The function in the test file to update')
   parser.add_argument('-u', '--update-only', action='store_true',
                       help='Only update test if it was already autogened')
   parser.add_argument('-p', '--preserve-names', action='store_true',
                       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()
 
+  # If requested we scrub trailing attribute annotations, e.g., '#0', together with whitespaces
+  if args.scrub_attributes:
+    common.SCRUB_TRAILING_WHITESPACE_RE = common.SCRUB_TRAILING_WHITESPACE_AND_ATTRIBUTES_RE
+
   script_name = os.path.basename(__file__)
   autogenerated_note = (ADVERT + 'utils/' + script_name)
 
   opt_basename = os.path.basename(args.opt_binary)
   if not re.match(r'^opt(-\d+)?$', opt_basename):
     common.error('Unexpected opt name: ' + opt_basename)
     sys.exit(1)
   opt_basename = 'opt'