common.py

from __future__ import print_function

import copy
import glob
import os
import re
import subprocess
import sys

##### Common utilities for update_*test_checks.py


_verbose = False
_prefix_filecheck_ir_name = ''

def parse_commandline_args(parser):
  parser.add_argument('--include-generated-funcs', action='store_true',
                      help='Output checks for functions not in source')
  parser.add_argument('-v', '--verbose', action='store_true',
                      help='Show verbose output')
  parser.add_argument('-u', '--update-only', action='store_true',
                      help='Only update test if it was already autogened')
  parser.add_argument('--force-update', action='store_true',
                      help='Update test even if it was autogened by a different script')
  parser.add_argument('--enable', action='store_true', dest='enabled', default=True,
                       help='Activate CHECK line generation from this point forward')
  parser.add_argument('--disable', action='store_false', dest='enabled',
                      help='Deactivate CHECK line generation from this point forward')
  parser.add_argument('--replace-value-regex', nargs='+', default=[],
                      help='List of regular expressions to replace matching value names')
  parser.add_argument('--prefix-filecheck-ir-name', default='',
                      help='Add a prefix to FileCheck IR value names to avoid conflicts with scripted names')
  parser.add_argument('--global-value-regex', nargs='+', default=[],
                      help='List of regular expressions that a global value declaration must match to generate a check (has no effect if checking globals is not enabled)')
  parser.add_argument('--global-hex-value-regex', nargs='+', default=[],
                      help='List of regular expressions such that, for matching global value declarations, literal integer values should be encoded in hex in the associated FileCheck directives')
  args = parser.parse_args()
  global _verbose, _global_value_regex, _global_hex_value_regex
  _verbose = args.verbose
  _global_value_regex = args.global_value_regex
  _global_hex_value_regex = args.global_hex_value_regex
  return args


class InputLineInfo(object):
  def __init__(self, line, line_number, args, argv):
    self.line = line
    self.line_number = line_number
    self.args = args
    self.argv = argv


class TestInfo(object):
  def __init__(self, test, parser, script_name, input_lines, args, argv,
               comment_prefix, argparse_callback):
    self.parser = parser
    self.argparse_callback = argparse_callback
    self.path = test
    self.args = args
    if args.prefix_filecheck_ir_name:
      global _prefix_filecheck_ir_name
      _prefix_filecheck_ir_name = args.prefix_filecheck_ir_name
    self.argv = argv
    self.input_lines = input_lines
    self.run_lines = find_run_lines(test, self.input_lines)
    self.comment_prefix = comment_prefix
    if self.comment_prefix is None:
      if self.path.endswith('.mir'):
        self.comment_prefix = '#'
      else:
        self.comment_prefix = ';'
    self.autogenerated_note_prefix = self.comment_prefix + ' ' + UTC_ADVERT
    self.test_autogenerated_note = self.autogenerated_note_prefix + script_name
    self.test_autogenerated_note += get_autogennote_suffix(parser, self.args)

  def ro_iterlines(self):
    for line_num, input_line in enumerate(self.input_lines):
      args, argv = check_for_command(input_line, self.parser,
                                     self.args, self.argv, self.argparse_callback)
      yield InputLineInfo(input_line, line_num, args, argv)

  def iterlines(self, output_lines):
    output_lines.append(self.test_autogenerated_note)
    for line_info in self.ro_iterlines():
      input_line = line_info.line
      # Discard any previous script advertising.
      if input_line.startswith(self.autogenerated_note_prefix):
        continue
      self.args = line_info.args
      self.argv = line_info.argv
      if not self.args.enabled:
        output_lines.append(input_line)
        continue
      yield line_info

def itertests(test_patterns, parser, script_name, comment_prefix=None, argparse_callback=None):
  for pattern in test_patterns:
    # On Windows we must expand the patterns ourselves.
    tests_list = glob.glob(pattern)
    if not tests_list:
      warn("Test file pattern '%s' was not found. Ignoring it." % (pattern,))
      continue
    for test in tests_list:
      with open(test) as f:
        input_lines = [l.rstrip() for l in f]
      args = parser.parse_args()
      if argparse_callback is not None:
        argparse_callback(args)
      argv = sys.argv[:]
      first_line = input_lines[0] if input_lines else ""
      if UTC_ADVERT in first_line:
        if script_name not in first_line and not args.force_update:
          warn("Skipping test which wasn't autogenerated by " + script_name, test)
          continue
        args, argv = check_for_command(first_line, parser, args, argv, argparse_callback)
      elif args.update_only:
        assert UTC_ADVERT not in first_line
        warn("Skipping test which isn't autogenerated: " + test)
        continue
      yield TestInfo(test, parser, script_name, input_lines, args, argv,
                     comment_prefix, argparse_callback)


def should_add_line_to_output(input_line, prefix_set, skip_global_checks = False, comment_marker = ';'):
  # Skip any blank comment lines in the IR.
  if not skip_global_checks and input_line.strip() == comment_marker:
    return False
  # Skip a special double comment line we use as a separator.
  if input_line.strip() == comment_marker + SEPARATOR:
    return False
  # Skip any blank lines in the IR.
  #if input_line.strip() == '':
  #  return False
  # And skip any CHECK lines. We're building our own.
  m = CHECK_RE.match(input_line)
  if m and m.group(1) in prefix_set:
    if skip_global_checks:
      global_ir_value_re = re.compile('\[\[', flags=(re.M))
      return not global_ir_value_re.search(input_line)
    return False

  return True

# Perform lit-like substitutions
def getSubstitutions(sourcepath):
  sourcedir = os.path.dirname(sourcepath)
  return [('%s', sourcepath),
          ('%S', sourcedir),
          ('%p', sourcedir),
          ('%{pathsep}', os.pathsep)]

def applySubstitutions(s, substitutions):
  for a,b in substitutions:
    s = s.replace(a, b)
  return s

# Invoke the tool that is being tested.
def invoke_tool(exe, cmd_args, ir, preprocess_cmd=None, verbose=False):
  with open(ir) as ir_file:
    substitutions = getSubstitutions(ir)

    # TODO Remove the str form which is used by update_test_checks.py and
    # update_llc_test_checks.py
    # The safer list form is used by update_cc_test_checks.py
    if preprocess_cmd:
      # Allow pre-processing the IR file (e.g. using sed):
      assert isinstance(preprocess_cmd, str)  # TODO: use a list instead of using shell
      preprocess_cmd = applySubstitutions(preprocess_cmd, substitutions).strip()
      if verbose:
        print('Pre-processing input file: ', ir, " with command '",
              preprocess_cmd, "'", sep="", file=sys.stderr)
      # Python 2.7 doesn't have subprocess.DEVNULL:
      with open(os.devnull, 'w') as devnull:
        pp = subprocess.Popen(preprocess_cmd, shell=True, stdin=devnull,
                              stdout=subprocess.PIPE)
        ir_file = pp.stdout

    if isinstance(cmd_args, list):
      args = [applySubstitutions(a, substitutions) for a in cmd_args]
      stdout = subprocess.check_output([exe] + args, stdin=ir_file)
    else:
      stdout = subprocess.check_output(exe + ' ' + applySubstitutions(cmd_args, substitutions),
                                       shell=True, stdin=ir_file)
    if sys.version_info[0] > 2:
      # FYI, if you crashed here with a decode error, your run line probably
      # results in bitcode or other binary format being written to the pipe.
      # For an opt test, you probably want to add -S or -disable-output.
      stdout = stdout.decode()
  # Fix line endings to unix CR style.
  return stdout.replace('\r\n', '\n')

##### LLVM IR parser
RUN_LINE_RE = re.compile(r'^\s*(?://|[;#])\s*RUN:\s*(.*)$')
CHECK_PREFIX_RE = re.compile(r'--?check-prefix(?:es)?[= ](\S+)')
PREFIX_RE = re.compile('^[a-zA-Z0-9_-]+$')
CHECK_RE = re.compile(r'^\s*(?://|[;#])\s*([^:]+?)(?:-NEXT|-NOT|-DAG|-LABEL|-SAME|-EMPTY)?:')

UTC_ARGS_KEY = 'UTC_ARGS:'
UTC_ARGS_CMD = re.compile(r'.*' + UTC_ARGS_KEY + '\s*(?P<cmd>.*)\s*$')
UTC_ADVERT = 'NOTE: Assertions have been autogenerated by '

OPT_FUNCTION_RE = re.compile(
    r'^(\s*;\s*Function\sAttrs:\s(?P<attrs>[\w\s]+?))?\s*define\s+(?:internal\s+)?[^@]*@(?P<func>[\w.$-]+?)\s*'
    r'(?P<args_and_sig>\((\)|(.*?[\w.-]+?)\))[^{]*\{)\n(?P<body>.*?)^\}$',
    flags=(re.M | re.S))

ANALYZE_FUNCTION_RE = re.compile(
    r'^\s*\'(?P<analysis>[\w\s-]+?)\'\s+for\s+function\s+\'(?P<func>[\w.$-]+?)\':'
    r'\s*\n(?P<body>.*)$',
    flags=(re.X | re.S))

IR_FUNCTION_RE = re.compile(r'^\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]+$', flags=re.M)
SCRUB_TRAILING_WHITESPACE_TEST_RE = SCRUB_TRAILING_WHITESPACE_RE
SCRUB_TRAILING_WHITESPACE_AND_ATTRIBUTES_RE = re.compile(r'([ \t]|(#[0-9]+))+$', 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)
SCRUB_TAILING_COMMENT_TOKEN_RE = re.compile(r'(?<=\S)+[ \t]*#$', flags=re.M)

SEPARATOR = '.'

def error(msg, test_file=None):
  if test_file:
    msg = '{}: {}'.format(msg, test_file)
  print('ERROR: {}'.format(msg), file=sys.stderr)

def warn(msg, test_file=None):
  if test_file:
    msg = '{}: {}'.format(msg, test_file)
  print('WARNING: {}'.format(msg), file=sys.stderr)

def debug(*args, **kwargs):
  # Python2 does not allow def debug(*args, file=sys.stderr, **kwargs):
  if 'file' not in kwargs:
    kwargs['file'] = sys.stderr
  if _verbose:
    print(*args, **kwargs)

def find_run_lines(test, lines):
  debug('Scanning for RUN lines in test file:', test)
  raw_lines = [m.group(1)
               for m in [RUN_LINE_RE.match(l) for l in lines] if m]
  run_lines = [raw_lines[0]] if len(raw_lines) > 0 else []
  for l in raw_lines[1:]:
    if run_lines[-1].endswith('\\'):
      run_lines[-1] = run_lines[-1].rstrip('\\') + ' ' + l
    else:
      run_lines.append(l)
  debug('Found {} RUN lines in {}:'.format(len(run_lines), test))
  for l in run_lines:
    debug('  RUN: {}'.format(l))
  return run_lines

def scrub_body(body):
  # Scrub runs of whitespace out of the assembly, but leave the leading
  # whitespace in place.
  body = SCRUB_WHITESPACE_RE.sub(r' ', body)
  # Expand the tabs used for indentation.
  body = str.expandtabs(body, 2)
  # Strip trailing whitespace.
  body = SCRUB_TRAILING_WHITESPACE_TEST_RE.sub(r'', body)
  return body

def do_scrub(body, scrubber, scrubber_args, extra):
  if scrubber_args:
    local_args = copy.deepcopy(scrubber_args)
    local_args[0].extra_scrub = extra
    return scrubber(body, *local_args)
  return scrubber(body, *scrubber_args)

# Build up a dictionary of all the function bodies.
class function_body(object):
  def __init__(self, string, extra, args_and_sig, attrs):
    self.scrub = string
    self.extrascrub = extra
    self.args_and_sig = args_and_sig
    self.attrs = attrs
  def is_same_except_arg_names(self, extrascrub, args_and_sig, attrs, is_asm):
    arg_names = set()
    def drop_arg_names(match):
        arg_names.add(match.group(variable_group_in_ir_value_match))
        if match.group(attribute_group_in_ir_value_match):
            attr = match.group(attribute_group_in_ir_value_match)
        else:
            attr = ''
        return match.group(1) + attr + match.group(match.lastindex)
    def repl_arg_names(match):
        if match.group(variable_group_in_ir_value_match) is not None and match.group(variable_group_in_ir_value_match) in arg_names:
            return match.group(1) + match.group(match.lastindex)
        return match.group(1) + match.group(2) + match.group(match.lastindex)
    if self.attrs != attrs:
      return False
    ans0 = IR_VALUE_RE.sub(drop_arg_names, self.args_and_sig)
    ans1 = IR_VALUE_RE.sub(drop_arg_names, args_and_sig)
    if ans0 != ans1:
        return False
    if is_asm:
        # Check without replacements, the replacements are not applied to the
        # body for asm checks.
        return self.extrascrub == extrascrub

    es0 = IR_VALUE_RE.sub(repl_arg_names, self.extrascrub)
    es1 = IR_VALUE_RE.sub(repl_arg_names, extrascrub)
    es0 = SCRUB_IR_COMMENT_RE.sub(r'', es0)
    es1 = SCRUB_IR_COMMENT_RE.sub(r'', es1)
    return es0 == es1

  def __str__(self):
    return self.scrub

class FunctionTestBuilder:
  def __init__(self, run_list, flags, scrubber_args, path):
    self._verbose = flags.verbose
    self._record_args = flags.function_signature
    self._check_attributes = flags.check_attributes
    self._scrubber_args = scrubber_args
    self._path = path
    # Strip double-quotes if input was read by UTC_ARGS
    self._replace_value_regex = list(map(lambda x: x.strip('"'), flags.replace_value_regex))
    self._func_dict = {}
    self._func_order = {}
    self._global_var_dict = {}
    for tuple in run_list:
      for prefix in tuple[0]:
        self._func_dict.update({prefix:dict()})
        self._func_order.update({prefix: []})
        self._global_var_dict.update({prefix:dict()})

  def finish_and_get_func_dict(self):
    for prefix in self._get_failed_prefixes():
      warn('Prefix %s had conflicting output from different RUN lines for all functions in test %s' % (prefix,self._path,))
    return self._func_dict

  def func_order(self):
    return self._func_order

  def global_var_dict(self):
    return self._global_var_dict

  def process_run_line(self, function_re, scrubber, raw_tool_output, prefixes, is_asm):
    build_global_values_dictionary(self._global_var_dict, raw_tool_output, prefixes)
    for m in function_re.finditer(raw_tool_output):
      if not m:
        continue
      func = m.group('func')
      body = m.group('body')
      attrs = m.group('attrs') if self._check_attributes else ''
      # Determine if we print arguments, the opening brace, or nothing after the
      # function name
      if self._record_args and 'args_and_sig' in m.groupdict():
          args_and_sig = scrub_body(m.group('args_and_sig').strip())
      elif 'args_and_sig' in m.groupdict():
          args_and_sig = '('
      else:
          args_and_sig = ''
      scrubbed_body = do_scrub(body, scrubber, self._scrubber_args,
                               extra=False)
      scrubbed_extra = do_scrub(body, scrubber, self._scrubber_args,
                                extra=True)
      if 'analysis' in m.groupdict():
        analysis = m.group('analysis')
        if analysis.lower() != 'cost model analysis':
          warn('Unsupported analysis mode: %r!' % (analysis,))
      if func.startswith('stress'):
        # We only use the last line of the function body for stress tests.
        scrubbed_body = '\n'.join(scrubbed_body.splitlines()[-1:])
      if self._verbose:
        print('Processing function: ' + func, file=sys.stderr)
        for l in scrubbed_body.splitlines():
          print('  ' + l, file=sys.stderr)
      for prefix in prefixes:
        # Replace function names matching the regex.
        for regex in self._replace_value_regex:
          # Pattern that matches capture groups in the regex in leftmost order.
          group_regex = re.compile('\(.*?\)')
          # Replace function name with regex.
          match = re.match(regex, func)
          if match:
            func_repl = regex
            # Replace any capture groups with their matched strings.
            for g in match.groups():
              func_repl = group_regex.sub(re.escape(g), func_repl, count=1)
            func = re.sub(func_repl, '{{' + func_repl + '}}', func)

          # Replace all calls to regex matching functions.
          matches = re.finditer(regex, scrubbed_body)
          for match in matches:
            func_repl = regex
            # Replace any capture groups with their matched strings.
            for g in match.groups():
                func_repl = group_regex.sub(re.escape(g), func_repl, count=1)
            # Substitute function call names that match the regex with the same
            # capture groups set.
            scrubbed_body = re.sub(func_repl, '{{' + func_repl + '}}',
                                   scrubbed_body)

        if func in self._func_dict[prefix]:
          if (self._func_dict[prefix][func] is None or
              str(self._func_dict[prefix][func]) != scrubbed_body or
              self._func_dict[prefix][func].args_and_sig != args_and_sig or
                  self._func_dict[prefix][func].attrs != attrs):
            if (self._func_dict[prefix][func] is not None and
                self._func_dict[prefix][func].is_same_except_arg_names(
                scrubbed_extra,
                args_and_sig,
                attrs,
                is_asm)):
              self._func_dict[prefix][func].scrub = scrubbed_extra
              self._func_dict[prefix][func].args_and_sig = args_and_sig
              continue
            else:
              # This means a previous RUN line produced a body for this function
              # that is different from the one produced by this current RUN line,
              # so the body can't be common accross RUN lines. We use None to
              # indicate that.
              self._func_dict[prefix][func] = None
              continue

        self._func_dict[prefix][func] = function_body(
            scrubbed_body, scrubbed_extra, args_and_sig, attrs)
        self._func_order[prefix].append(func)

  def _get_failed_prefixes(self):
    # This returns the list of those prefixes that failed to match any function,
    # because there were conflicting bodies produced by different RUN lines, in
    # all instances of the prefix. Effectively, this prefix is unused and should
    # be removed.
    for prefix in self._func_dict:
      if (self._func_dict[prefix] and
          (not [fct for fct in self._func_dict[prefix]
                if self._func_dict[prefix][fct] is not None])):
        yield prefix


##### Generator of LLVM IR CHECK lines

SCRUB_IR_COMMENT_RE = re.compile(r'\s*;.*')

# TODO: We should also derive check lines for global, debug, loop declarations, etc..

class NamelessValue:
    def __init__(self, check_prefix, check_key, ir_prefix, global_ir_prefix, global_ir_prefix_regexp,
                 ir_regexp, global_ir_rhs_regexp, is_before_functions):
        self.check_prefix = check_prefix
        self.check_key = check_key
        self.ir_prefix = ir_prefix
        self.global_ir_prefix = global_ir_prefix
        self.global_ir_prefix_regexp = global_ir_prefix_regexp
        self.ir_regexp = ir_regexp
        self.global_ir_rhs_regexp = global_ir_rhs_regexp
        self.is_before_functions = is_before_functions

# Description of the different "unnamed" values we match in the IR, e.g.,
# (local) ssa values, (debug) metadata, etc.
nameless_values = [
    NamelessValue(r'TMP'  , '%' , r'%'           , None            , None                   , r'[\w$.-]+?' , None                 , False) ,
    NamelessValue(r'ATTR' , '#' , r'#'           , None            , None                   , r'[0-9]+'    , None                 , False) ,
    NamelessValue(r'ATTR' , '#' , None           , r'attributes #' , r'[0-9]+'              , None         , r'{[^}]*}'           , False) ,
    NamelessValue(r'GLOB' , '@' , r'@'           , None            , None                   , r'[0-9]+'    , None                 , False) ,
    NamelessValue(r'GLOB' , '@' , None           , r'@'            , r'[a-zA-Z0-9_$"\\.-]+' , None         , r'.+'                , True)  ,
    NamelessValue(r'DBG'  , '!' , r'!dbg '       , None            , None                   , r'![0-9]+'   , None                 , False) ,
    NamelessValue(r'PROF' , '!' , r'!prof '      , None            , None                   , r'![0-9]+'   , None                 , False) ,
    NamelessValue(r'TBAA' , '!' , r'!tbaa '      , None            , None                   , r'![0-9]+'   , None                 , False) ,
    NamelessValue(r'RNG'  , '!' , r'!range '     , None            , None                   , r'![0-9]+'   , None                 , False) ,
    NamelessValue(r'LOOP' , '!' , r'!llvm.loop ' , None            , None                   , r'![0-9]+'   , None                 , False) ,
    NamelessValue(r'META' , '!' , r'metadata '   , None            , None                   , r'![0-9]+'   , None                 , False) ,
    NamelessValue(r'META' , '!' , None           , r''             , r'![0-9]+'             , None         , r'(?:distinct |)!.*' , False) ,
]

def createOrRegexp(old, new):
    if not old:
        return new
    if not new:
        return old
    return old + '|' + new

def createPrefixMatch(prefix_str, prefix_re):
    if prefix_str is None or prefix_re is None:
        return ''
    return '(?:' + prefix_str + '(' + prefix_re + '))'

# Build the regexp that matches an "IR value". This can be a local variable,
# argument, global, or metadata, anything that is "named". It is important that
# the PREFIX and SUFFIX below only contain a single group, if that changes
# other locations will need adjustment as well.
IR_VALUE_REGEXP_PREFIX = r'(\s*)'
IR_VALUE_REGEXP_STRING = r''
for nameless_value in nameless_values:
    lcl_match = createPrefixMatch(nameless_value.ir_prefix, nameless_value.ir_regexp)
    glb_match = createPrefixMatch(nameless_value.global_ir_prefix, nameless_value.global_ir_prefix_regexp)
    assert((lcl_match or glb_match) and not (lcl_match and glb_match))
    if lcl_match:
        IR_VALUE_REGEXP_STRING = createOrRegexp(IR_VALUE_REGEXP_STRING, lcl_match)
    elif glb_match:
        IR_VALUE_REGEXP_STRING = createOrRegexp(IR_VALUE_REGEXP_STRING, '^' + glb_match)
IR_VALUE_REGEXP_SUFFIX = r'([,\s\(\)]|\Z)'
IR_VALUE_RE = re.compile(IR_VALUE_REGEXP_PREFIX + r'(' + IR_VALUE_REGEXP_STRING + r')' + IR_VALUE_REGEXP_SUFFIX)

# The entire match is group 0, the prefix has one group (=1), the entire
# IR_VALUE_REGEXP_STRING is one group (=2), and then the nameless values start.
first_nameless_group_in_ir_value_match = 3

# constants for the group id of special matches
variable_group_in_ir_value_match = 3
attribute_group_in_ir_value_match = 4

# Check a match for IR_VALUE_RE and inspect it to determine if it was a local
# value, %..., global @..., debug number !dbg !..., etc. See the PREFIXES above.
def get_idx_from_ir_value_match(match):
    for i in range(first_nameless_group_in_ir_value_match, match.lastindex):
        if match.group(i) is not None:
            return i - first_nameless_group_in_ir_value_match
    error("Unable to identify the kind of IR value from the match!")
    return 0

# See get_idx_from_ir_value_match
def get_name_from_ir_value_match(match):
    return match.group(get_idx_from_ir_value_match(match) + first_nameless_group_in_ir_value_match)

# Return the nameless prefix we use for this kind or IR value, see also
# get_idx_from_ir_value_match
def get_nameless_check_prefix_from_ir_value_match(match):
    return nameless_values[get_idx_from_ir_value_match(match)].check_prefix

# Return the IR prefix and check prefix we use for this kind or IR value, e.g., (%, TMP) for locals,
# see also get_idx_from_ir_value_match
def get_ir_prefix_from_ir_value_match(match):
    idx = get_idx_from_ir_value_match(match)
    if nameless_values[idx].ir_prefix and match.group(0).strip().startswith(nameless_values[idx].ir_prefix):
        return nameless_values[idx].ir_prefix, nameless_values[idx].check_prefix
    return nameless_values[idx].global_ir_prefix, nameless_values[idx].check_prefix

def get_check_key_from_ir_value_match(match):
    idx = get_idx_from_ir_value_match(match)
    return nameless_values[idx].check_key

# Return the IR regexp we use for this kind or IR value, e.g., [\w.-]+? for locals,
# see also get_idx_from_ir_value_match
def get_ir_prefix_from_ir_value_re_match(match):
    # for backwards compatibility we check locals with '.*'
    if is_local_def_ir_value_match(match):
        return '.*'
    idx = get_idx_from_ir_value_match(match)
    if nameless_values[idx].ir_prefix and match.group(0).strip().startswith(nameless_values[idx].ir_prefix):
        return nameless_values[idx].ir_regexp
    return nameless_values[idx].global_ir_prefix_regexp

# Return true if this kind of IR value is "local", basically if it matches '%{{.*}}'.
def is_local_def_ir_value_match(match):
    return nameless_values[get_idx_from_ir_value_match(match)].ir_prefix == '%'

# Return true if this kind of IR value is "global", basically if it matches '#{{.*}}'.
def is_global_scope_ir_value_match(match):
    return nameless_values[get_idx_from_ir_value_match(match)].global_ir_prefix is not None

# Return true if var clashes with the scripted FileCheck check_prefix.
def may_clash_with_default_check_prefix_name(check_prefix, var):
  return check_prefix and re.match(r'^' + check_prefix + r'[0-9]+?$', var, re.IGNORECASE)

# Create a FileCheck variable name based on an IR name.
def get_value_name(var, check_prefix):
  var = var.replace('!', '')
  # This is a nameless value, prepend check_prefix.
  if var.isdigit():
    var = check_prefix + var
  else:
    # This is a named value that clashes with the check_prefix, prepend with _prefix_filecheck_ir_name,
    # if it has been defined.
    if may_clash_with_default_check_prefix_name(check_prefix, var) and _prefix_filecheck_ir_name:
      var = _prefix_filecheck_ir_name + var
  var = var.replace('.', '_')
  var = var.replace('-', '_')
  return var.upper()

# Create a FileCheck variable from regex.
def get_value_definition(var, match):
  # for backwards compatibility we check locals with '.*'
  if is_local_def_ir_value_match(match):
    return '[[' + get_value_name(var, get_nameless_check_prefix_from_ir_value_match(match)) + ':' + \
            get_ir_prefix_from_ir_value_match(match)[0] + get_ir_prefix_from_ir_value_re_match(match) + ']]'
  prefix = get_ir_prefix_from_ir_value_match(match)[0]
  return prefix + '[[' + get_value_name(var, get_nameless_check_prefix_from_ir_value_match(match)) + ':' + get_ir_prefix_from_ir_value_re_match(match) + ']]'

# Use a FileCheck variable.
def get_value_use(var, match, check_prefix):
  if is_local_def_ir_value_match(match):
    return '[[' + get_value_name(var, check_prefix) + ']]'
  prefix = get_ir_prefix_from_ir_value_match(match)[0]
  return prefix + '[[' + get_value_name(var, check_prefix) + ']]'

# Replace IR value defs and uses with FileCheck variables.
def generalize_check_lines(lines, is_analyze, vars_seen, global_vars_seen):
  # This gets called for each match that occurs in
  # a line. We transform variables we haven't seen
  # into defs, and variables we have seen into uses.
  def transform_line_vars(match):
    pre, check = get_ir_prefix_from_ir_value_match(match)
    var = get_name_from_ir_value_match(match)
    for nameless_value in nameless_values:
        if may_clash_with_default_check_prefix_name(nameless_value.check_prefix, var):
          warn("Change IR value name '%s' or use -prefix-ir-filecheck-name to prevent possible conflict"
            " with scripted FileCheck name." % (var,))
    key = (var, get_check_key_from_ir_value_match(match))
    is_local_def = is_local_def_ir_value_match(match)
    if is_local_def and key in vars_seen:
      rv = get_value_use(var, match, get_nameless_check_prefix_from_ir_value_match(match))
    elif not is_local_def and key in global_vars_seen:
      rv = get_value_use(var, match, global_vars_seen[key])
    else:
      if is_local_def:
         vars_seen.add(key)
      else:
         global_vars_seen[key] = get_nameless_check_prefix_from_ir_value_match(match)
      rv = get_value_definition(var, match)
    # re.sub replaces the entire regex match
    # with whatever you return, so we have
    # to make sure to hand it back everything
    # including the commas and spaces.
    return match.group(1) + rv + match.group(match.lastindex)

  lines_with_def = []

  for i, line in enumerate(lines):
    # An IR variable named '%.' matches the FileCheck regex string.
    line = line.replace('%.', '%dot')
    for regex in _global_hex_value_regex:
      if re.match('^@' + regex + ' = ', line):
        line = re.sub(r'\bi([0-9]+) ([0-9]+)',
            lambda m : 'i' + m.group(1) + ' [[#' + hex(int(m.group(2))) + ']]',
            line)
        break
    # Ignore any comments, since the check lines will too.
    scrubbed_line = SCRUB_IR_COMMENT_RE.sub(r'', line)
    lines[i] = scrubbed_line
    if not is_analyze:
      # It can happen that two matches are back-to-back and for some reason sub
      # will not replace both of them. For now we work around this by
      # substituting until there is no more match.
      changed = True
      while changed:
          (lines[i], changed) = IR_VALUE_RE.subn(transform_line_vars, lines[i], count=1)
  return lines


def add_checks(output_lines, comment_marker, prefix_list, func_dict, func_name, check_label_format, is_asm, is_analyze, global_vars_seen_dict):
  # prefix_exclusions are prefixes we cannot use to print the function because it doesn't exist in run lines that use these prefixes as well.
  prefix_exclusions = set()
  printed_prefixes = []
  for p in prefix_list:
    checkprefixes = p[0]
    # If not all checkprefixes of this run line produced the function we cannot check for it as it does not
    # exist for this run line. A subset of the check prefixes might know about the function but only because
    # other run lines created it.
    if any(map(lambda checkprefix: func_name not in func_dict[checkprefix], checkprefixes)):
        prefix_exclusions |= set(checkprefixes)
        continue

  # prefix_exclusions is constructed, we can now emit the output
  for p in prefix_list:
    global_vars_seen = {}
    checkprefixes = p[0]
    for checkprefix in checkprefixes:
      if checkprefix in global_vars_seen_dict:
        global_vars_seen.update(global_vars_seen_dict[checkprefix])
      else:
        global_vars_seen_dict[checkprefix] = {}
      if checkprefix in printed_prefixes:
        break

      # Check if the prefix is excluded.
      if checkprefix in prefix_exclusions:
        continue

      # If we do not have output for this prefix we skip it.
      if not func_dict[checkprefix][func_name]:
        continue

      # Add some space between different check prefixes, but not after the last
      # check line (before the test code).
      if is_asm:
        if len(printed_prefixes) != 0:
          output_lines.append(comment_marker)

      if checkprefix not in global_vars_seen_dict:
          global_vars_seen_dict[checkprefix] = {}

      global_vars_seen_before = [key for key in global_vars_seen.keys()]

      vars_seen = set()
      printed_prefixes.append(checkprefix)
      attrs = str(func_dict[checkprefix][func_name].attrs)
      attrs = '' if attrs == 'None' else attrs
      if attrs:
        output_lines.append('%s %s: Function Attrs: %s' % (comment_marker, checkprefix, attrs))
      args_and_sig = str(func_dict[checkprefix][func_name].args_and_sig)
      args_and_sig = generalize_check_lines([args_and_sig], is_analyze, vars_seen, global_vars_seen)[0]
      if '[[' in args_and_sig:
        output_lines.append(check_label_format % (checkprefix, func_name, ''))
        output_lines.append('%s %s-SAME: %s' % (comment_marker, checkprefix, args_and_sig))
      else:
        output_lines.append(check_label_format % (checkprefix, func_name, args_and_sig))
      func_body = str(func_dict[checkprefix][func_name]).splitlines()

      # For ASM output, just emit the check lines.
      if is_asm:
        output_lines.append('%s %s:       %s' % (comment_marker, checkprefix, func_body[0]))
        for func_line in func_body[1:]:
          if func_line.strip() == '':
            output_lines.append('%s %s-EMPTY:' % (comment_marker, checkprefix))
          else:
            output_lines.append('%s %s-NEXT:  %s' % (comment_marker, checkprefix, func_line))
        break

      # For IR output, change all defs to FileCheck variables, so we're immune
      # to variable naming fashions.
      func_body = generalize_check_lines(func_body, is_analyze, vars_seen, global_vars_seen)

      # This could be selectively enabled with an optional invocation argument.
      # Disabled for now: better to check everything. Be safe rather than sorry.

      # Handle the first line of the function body as a special case because
      # it's often just noise (a useless asm comment or entry label).
      #if func_body[0].startswith("#") or func_body[0].startswith("entry:"):
      #  is_blank_line = True
      #else:
      #  output_lines.append('%s %s:       %s' % (comment_marker, checkprefix, func_body[0]))
      #  is_blank_line = False

      is_blank_line = False

      for func_line in func_body:
        if func_line.strip() == '':
          is_blank_line = True
          continue
        # Do not waste time checking IR comments.
        func_line = SCRUB_IR_COMMENT_RE.sub(r'', func_line)

        # Skip blank lines instead of checking them.
        if is_blank_line:
          output_lines.append('{} {}:       {}'.format(
              comment_marker, checkprefix, func_line))
        else:
          output_lines.append('{} {}-NEXT:  {}'.format(
              comment_marker, checkprefix, func_line))
        is_blank_line = False

      # Add space between different check prefixes and also before the first
      # line of code in the test function.
      output_lines.append(comment_marker)

      # Remembe new global variables we have not seen before
      for key in global_vars_seen:
          if key not in global_vars_seen_before:
              global_vars_seen_dict[checkprefix][key] = global_vars_seen[key]
      break

def add_ir_checks(output_lines, comment_marker, prefix_list, func_dict,
                  func_name, preserve_names, function_sig, global_vars_seen_dict):
  # Label format is based on IR string.
  function_def_regex = 'define {{[^@]+}}' if function_sig else ''
  check_label_format = '{} %s-LABEL: {}@%s%s'.format(comment_marker, function_def_regex)
  add_checks(output_lines, comment_marker, prefix_list, func_dict, func_name,
             check_label_format, False, preserve_names, global_vars_seen_dict)

def add_analyze_checks(output_lines, comment_marker, prefix_list, func_dict, func_name):
  check_label_format = '{} %s-LABEL: \'%s%s\''.format(comment_marker)
  global_vars_seen_dict = {}
  add_checks(output_lines, comment_marker, prefix_list, func_dict, func_name,
             check_label_format, False, True, global_vars_seen_dict)

def build_global_values_dictionary(glob_val_dict, raw_tool_output, prefixes):
  for nameless_value in nameless_values:
    if nameless_value.global_ir_prefix is None:
      continue

    lhs_re_str = nameless_value.global_ir_prefix + nameless_value.global_ir_prefix_regexp
    rhs_re_str = nameless_value.global_ir_rhs_regexp

    global_ir_value_re_str = r'^' + lhs_re_str + r'\s=\s' + rhs_re_str + r'$'
    global_ir_value_re = re.compile(global_ir_value_re_str, flags=(re.M))
    lines = []
    for m in global_ir_value_re.finditer(raw_tool_output):
        lines.append(m.group(0))

    for prefix in prefixes:
      if glob_val_dict[prefix] is None:
        continue
      if nameless_value.check_prefix in glob_val_dict[prefix]:
        if lines == glob_val_dict[prefix][nameless_value.check_prefix]:
          continue
        if prefix == prefixes[-1]:
          warn('Found conflicting asm under the same prefix: %r!' % (prefix,))
        else:
          glob_val_dict[prefix][nameless_value.check_prefix] = None
          continue
      glob_val_dict[prefix][nameless_value.check_prefix] = lines

def add_global_checks(glob_val_dict, comment_marker, prefix_list, output_lines, global_vars_seen_dict, is_analyze, is_before_functions):
  printed_prefixes = set()
  for nameless_value in nameless_values:
    if nameless_value.global_ir_prefix is None:
        continue
    if nameless_value.is_before_functions != is_before_functions:
        continue
    for p in prefix_list:
      global_vars_seen = {}
      checkprefixes = p[0]
      if checkprefixes is None:
        continue
      for checkprefix in checkprefixes:
        if checkprefix in global_vars_seen_dict:
            global_vars_seen.update(global_vars_seen_dict[checkprefix])
        else:
            global_vars_seen_dict[checkprefix] = {}
        if (checkprefix, nameless_value.check_prefix) in printed_prefixes:
          break
        if not glob_val_dict[checkprefix]:
          continue
        if nameless_value.check_prefix not in glob_val_dict[checkprefix]:
          continue
        if not glob_val_dict[checkprefix][nameless_value.check_prefix]:
          continue

        check_lines = []
        global_vars_seen_before = [key for key in global_vars_seen.keys()]
        for line in glob_val_dict[checkprefix][nameless_value.check_prefix]:
          if _global_value_regex:
            matched = False
            for regex in _global_value_regex:
              if re.match('^@' + regex + ' = ', line):
                matched = True
                break
            if not matched:
              continue
          tmp = generalize_check_lines([line], is_analyze, set(), global_vars_seen)
          check_line = '%s %s: %s' % (comment_marker, checkprefix, tmp[0])
          check_lines.append(check_line)
        if not check_lines:
          continue

        output_lines.append(comment_marker + SEPARATOR)
        for check_line in check_lines:
          output_lines.append(check_line)

        printed_prefixes.add((checkprefix, nameless_value.check_prefix))

        # Remembe new global variables we have not seen before
        for key in global_vars_seen:
            if key not in global_vars_seen_before:
                global_vars_seen_dict[checkprefix][key] = global_vars_seen[key]
        break

  if printed_prefixes:
      output_lines.append(comment_marker + SEPARATOR)


def check_prefix(prefix):
  if not PREFIX_RE.match(prefix):
        hint = ""
        if ',' in prefix:
          hint = " Did you mean '--check-prefixes=" + prefix + "'?"
        warn(("Supplied prefix '%s' is invalid. Prefix must contain only alphanumeric characters, hyphens and underscores." + hint) %
             (prefix))


def verify_filecheck_prefixes(fc_cmd):
  fc_cmd_parts = fc_cmd.split()
  for part in fc_cmd_parts:
    if "check-prefix=" in part:
      prefix = part.split('=', 1)[1]
      check_prefix(prefix)
    elif "check-prefixes=" in part:
      prefixes = part.split('=', 1)[1].split(',')
      for prefix in prefixes:
        check_prefix(prefix)
        if prefixes.count(prefix) > 1:
          warn("Supplied prefix '%s' is not unique in the prefix list." % (prefix,))


def get_autogennote_suffix(parser, args):
  autogenerated_note_args = ''
  for action in parser._actions:
    if not hasattr(args, action.dest):
      continue  # Ignore options such as --help that aren't included in args
    # Ignore parameters such as paths to the binary or the list of tests
    if action.dest in ('tests', 'update_only', 'opt_binary', 'llc_binary',
                       'clang', 'opt', 'llvm_bin', 'verbose'):
      continue
    value = getattr(args, action.dest)
    if action.const is not None:  # action stores a constant (usually True/False)
      # Skip actions with different constant values (this happens with boolean
      # --foo/--no-foo options)
      if value != action.const:
        continue
    if parser.get_default(action.dest) == value:
      continue  # Don't add default values
    autogenerated_note_args += action.option_strings[0] + ' '
    if action.const is None:  # action takes a parameter
      if action.nargs == '+':
        value = ' '.join(map(lambda v: '"' + v.strip('"') + '"', value))
      autogenerated_note_args += '%s ' % value
  if autogenerated_note_args:
    autogenerated_note_args = ' %s %s' % (UTC_ARGS_KEY, autogenerated_note_args[:-1])
  return autogenerated_note_args


def check_for_command(line, parser, args, argv, argparse_callback):
    cmd_m = UTC_ARGS_CMD.match(line)
    if cmd_m:
        for option in cmd_m.group('cmd').strip().split(' '):
            if option:
                argv.append(option)
        args = parser.parse_args(filter(lambda arg: arg not in args.tests, argv))
        if argparse_callback is not None:
          argparse_callback(args)
    return args, argv

def find_arg_in_test(test_info, get_arg_to_check, arg_string, is_global):
  result = get_arg_to_check(test_info.args)
  if not result and is_global:
    # See if this has been specified via UTC_ARGS.  This is a "global" option
    # that affects the entire generation of test checks.  If it exists anywhere
    # in the test, apply it to everything.
    saw_line = False
    for line_info in test_info.ro_iterlines():
      line = line_info.line
      if not line.startswith(';') and line.strip() != '':
        saw_line = True
      result = get_arg_to_check(line_info.args)
      if result:
        if warn and saw_line:
          # We saw the option after already reading some test input lines.
          # Warn about it.
          print('WARNING: Found {} in line following test start: '.format(arg_string)
                + line, file=sys.stderr)
          print('WARNING: Consider moving {} to top of file'.format(arg_string),
                file=sys.stderr)
        break
  return result

def dump_input_lines(output_lines, test_info, prefix_set, comment_string):
  for input_line_info in test_info.iterlines(output_lines):
    line = input_line_info.line
    args = input_line_info.args
    if line.strip() == comment_string:
      continue
    if line.strip() == comment_string + SEPARATOR:
      continue
    if line.lstrip().startswith(comment_string):
      m = CHECK_RE.match(line)
      if m and m.group(1) in prefix_set:
        continue
    output_lines.append(line.rstrip('\n'))

def add_checks_at_end(output_lines, prefix_list, func_order,
                      comment_string, check_generator):
  added = set()
  for prefix in prefix_list:
    prefixes = prefix[0]
    tool_args = prefix[1]
    for prefix in prefixes:
      for func in func_order[prefix]:
        if added:
          output_lines.append(comment_string)
        added.add(func)

        # The add_*_checks routines expect a run list whose items are
        # tuples that have a list of prefixes as their first element and
        # tool command args string as their second element.  They output
        # checks for each prefix in the list of prefixes.  By doing so, it
        # implicitly assumes that for each function every run line will
        # generate something for that function.  That is not the case for
        # generated functions as some run lines might not generate them
        # (e.g. -fopenmp vs. no -fopenmp).
        #
        # Therefore, pass just the prefix we're interested in.  This has
        # the effect of generating all of the checks for functions of a
        # single prefix before moving on to the next prefix.  So checks
        # are ordered by prefix instead of by function as in "normal"
        # mode.
        check_generator(output_lines,
                        [([prefix], tool_args)],
                        func)