--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/utils/update_cc_test_checks.py	Mon May 25 11:07:02 2020 +0900
@@ -0,0 +1,301 @@
+#!/usr/bin/env python3
+'''A utility to update LLVM IR CHECK lines in C/C++ FileCheck test files.
+
+Example RUN lines in .c/.cc test files:
+
+// RUN: %clang -emit-llvm -S %s -o - -O2 | FileCheck %s
+// RUN: %clangxx -emit-llvm -S %s -o - -O2 | FileCheck -check-prefix=CHECK-A %s
+
+Usage:
+
+% utils/update_cc_test_checks.py --llvm-bin=release/bin test/a.cc
+% utils/update_cc_test_checks.py --c-index-test=release/bin/c-index-test \
+  --clang=release/bin/clang /tmp/c/a.cc
+'''
+
+import argparse
+import collections
+import distutils.spawn
+import os
+import shlex
+import string
+import subprocess
+import sys
+import re
+import tempfile
+
+from UpdateTestChecks import asm, common
+
+ADVERT = '// NOTE: Assertions have been autogenerated by '
+
+CHECK_RE = re.compile(r'^\s*//\s*([^:]+?)(?:-NEXT|-NOT|-DAG|-LABEL)?:')
+RUN_LINE_RE = re.compile('^//\s*RUN:\s*(.*)$')
+
+SUBST = {
+    '%clang': [],
+    '%clang_cc1': ['-cc1'],
+    '%clangxx': ['--driver-mode=g++'],
+}
+
+def get_line2spell_and_mangled(args, clang_args):
+  ret = {}
+  with tempfile.NamedTemporaryFile() as f:
+    # TODO Make c-index-test print mangled names without circumventing through precompiled headers
+    status = subprocess.run([args.c_index_test, '-write-pch', f.name, *clang_args],
+                            stdout=subprocess.PIPE, stderr=subprocess.STDOUT)
+    if status.returncode:
+      sys.stderr.write(status.stdout.decode())
+      sys.exit(2)
+    output = subprocess.check_output([args.c_index_test,
+        '-test-print-mangle', f.name])
+    if sys.version_info[0] > 2:
+      output = output.decode()
+  DeclRE = re.compile(r'^FunctionDecl=(\w+):(\d+):\d+ \(Definition\)')
+  MangleRE = re.compile(r'.*\[mangled=([^]]+)\]')
+  MatchedDecl = False
+  for line in output.splitlines():
+    # Get the function source name, line number and mangled name.  Sometimes
+    # c-index-test outputs the mangled name on a separate line (this can happen
+    # with block comments in front of functions).  Keep scanning until we see
+    # the mangled name.
+    decl_m = DeclRE.match(line)
+    mangle_m = MangleRE.match(line)
+
+    if decl_m:
+      MatchedDecl = True
+      spell, lineno = decl_m.groups()
+    if MatchedDecl and mangle_m:
+      mangled = mangle_m.group(1)
+      MatchedDecl = False
+    else:
+      continue
+
+    if mangled == '_' + spell:
+      # HACK for MacOS (where the mangled name includes an _ for C but the IR won't):
+      mangled = spell
+    # Note -test-print-mangle does not print file names so if #include is used,
+    # the line number may come from an included file.
+    ret[int(lineno)-1] = (spell, mangled)
+  if args.verbose:
+    for line, func_name in sorted(ret.items()):
+      print('line {}: found function {}'.format(line+1, func_name), file=sys.stderr)
+  return ret
+
+
+def config():
+  parser = argparse.ArgumentParser(
+      description=__doc__,
+      formatter_class=argparse.RawTextHelpFormatter)
+  parser.add_argument('-v', '--verbose', action='store_true')
+  parser.add_argument('--llvm-bin', help='llvm $prefix/bin path')
+  parser.add_argument('--clang',
+                      help='"clang" executable, defaults to $llvm_bin/clang')
+  parser.add_argument('--clang-args',
+                      help='Space-separated extra args to clang, e.g. --clang-args=-v')
+  parser.add_argument('--c-index-test',
+                      help='"c-index-test" executable, defaults to $llvm_bin/c-index-test')
+  parser.add_argument('--opt',
+                      help='"opt" executable, defaults to $llvm_bin/opt')
+  parser.add_argument(
+      '--functions', nargs='+', help='A list of function name regexes. '
+      'If specified, update CHECK lines for functions matching at least one regex')
+  parser.add_argument(
+      '--x86_extra_scrub', action='store_true',
+      help='Use more regex for x86 matching to reduce diffs between various subtargets')
+  parser.add_argument('-u', '--update-only', action='store_true',
+                      help='Only update test if it was already autogened')
+  parser.add_argument('tests', nargs='+')
+  args = parser.parse_args()
+  args.clang_args = shlex.split(args.clang_args or '')
+
+  if args.clang is None:
+    if args.llvm_bin is None:
+      args.clang = 'clang'
+    else:
+      args.clang = os.path.join(args.llvm_bin, 'clang')
+  if not distutils.spawn.find_executable(args.clang):
+    print('Please specify --llvm-bin or --clang', file=sys.stderr)
+    sys.exit(1)
+
+  if args.opt is None:
+    if args.llvm_bin is None:
+      args.opt = 'opt'
+    else:
+      args.opt = os.path.join(args.llvm_bin, 'opt')
+  if not distutils.spawn.find_executable(args.opt):
+    # Many uses of this tool will not need an opt binary, because it's only
+    # needed for updating a test that runs clang | opt | FileCheck. So we
+    # defer this error message until we find that opt is actually needed.
+    args.opt = None
+
+  if args.c_index_test is None:
+    if args.llvm_bin is None:
+      args.c_index_test = 'c-index-test'
+    else:
+      args.c_index_test = os.path.join(args.llvm_bin, 'c-index-test')
+  if not distutils.spawn.find_executable(args.c_index_test):
+    print('Please specify --llvm-bin or --c-index-test', file=sys.stderr)
+    sys.exit(1)
+
+  return args
+
+
+def get_function_body(args, filename, clang_args, extra_commands, prefixes, triple_in_cmd, func_dict):
+  # TODO Clean up duplication of asm/common build_function_body_dictionary
+  # Invoke external tool and extract function bodies.
+  raw_tool_output = common.invoke_tool(args.clang, clang_args, filename)
+  for extra_command in extra_commands:
+    extra_args = shlex.split(extra_command)
+    with tempfile.NamedTemporaryFile() as f:
+      f.write(raw_tool_output.encode())
+      f.flush()
+      if extra_args[0] == 'opt':
+        if args.opt is None:
+          print(filename, 'needs to run opt. '
+                'Please specify --llvm-bin or --opt', file=sys.stderr)
+          sys.exit(1)
+        extra_args[0] = args.opt
+      raw_tool_output = common.invoke_tool(extra_args[0],
+                                           extra_args[1:], f.name)
+  if '-emit-llvm' in clang_args:
+    common.build_function_body_dictionary(
+            common.OPT_FUNCTION_RE, common.scrub_body, [],
+            raw_tool_output, prefixes, func_dict, args.verbose)
+  else:
+    print('The clang command line should include -emit-llvm as asm tests '
+          'are discouraged in Clang testsuite.', file=sys.stderr)
+    sys.exit(1)
+
+
+def main():
+  args = config()
+  script_name = os.path.basename(__file__)
+  autogenerated_note = (ADVERT + 'utils/' + script_name)
+
+  for filename in args.tests:
+    with open(filename) as f:
+      input_lines = [l.rstrip() for l in f]
+    
+    first_line = input_lines[0] if input_lines else ""
+    if 'autogenerated' in first_line and script_name not in first_line:
+      common.warn("Skipping test which wasn't autogenerated by " + script_name, filename)
+      continue
+
+    if args.update_only:
+      if not first_line or 'autogenerated' not in first_line:
+        common.warn("Skipping test which isn't autogenerated: " + filename)
+        continue
+
+    # Extract RUN lines.
+    raw_lines = [m.group(1)
+                 for m in [RUN_LINE_RE.match(l) for l in input_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)
+
+    if args.verbose:
+      print('Found {} RUN lines:'.format(len(run_lines)), file=sys.stderr)
+      for l in run_lines:
+        print('  RUN: ' + l, file=sys.stderr)
+
+    # Build a list of clang command lines and check prefixes from RUN lines.
+    run_list = []
+    line2spell_and_mangled_list = collections.defaultdict(list)
+    for l in run_lines:
+      commands = [cmd.strip() for cmd in l.split('|')]
+
+      triple_in_cmd = None
+      m = common.TRIPLE_ARG_RE.search(commands[0])
+      if m:
+        triple_in_cmd = m.groups()[0]
+
+      # Apply %clang substitution rule, replace %s by `filename`, and append args.clang_args
+      clang_args = shlex.split(commands[0])
+      if clang_args[0] not in SUBST:
+        print('WARNING: Skipping non-clang RUN line: ' + l, file=sys.stderr)
+        continue
+      clang_args[0:1] = SUBST[clang_args[0]]
+      clang_args = [filename if i == '%s' else i for i in clang_args] + args.clang_args
+
+      # Permit piping the output through opt
+      if not (len(commands) == 2 or
+              (len(commands) == 3 and commands[1].startswith('opt'))):
+        print('WARNING: Skipping non-clang RUN line: ' + l, file=sys.stderr)
+
+      # Extract -check-prefix in FileCheck args
+      filecheck_cmd = commands[-1]
+      common.verify_filecheck_prefixes(filecheck_cmd)
+      if not filecheck_cmd.startswith('FileCheck '):
+        print('WARNING: Skipping non-FileChecked RUN line: ' + l, file=sys.stderr)
+        continue
+      check_prefixes = [item for m in common.CHECK_PREFIX_RE.finditer(filecheck_cmd)
+                               for item in m.group(1).split(',')]
+      if not check_prefixes:
+        check_prefixes = ['CHECK']
+      run_list.append((check_prefixes, clang_args, commands[1:-1], triple_in_cmd))
+
+    # Strip CHECK lines which are in `prefix_set`, update test file.
+    prefix_set = set([prefix for p in run_list for prefix in p[0]])
+    input_lines = []
+    with open(filename, 'r+') as f:
+      for line in f:
+        m = CHECK_RE.match(line)
+        if not (m and m.group(1) in prefix_set) and line != '//\n':
+          input_lines.append(line)
+      f.seek(0)
+      f.writelines(input_lines)
+      f.truncate()
+
+    # Execute clang, generate LLVM IR, and extract functions.
+    func_dict = {}
+    for p in run_list:
+      prefixes = p[0]
+      for prefix in prefixes:
+        func_dict.update({prefix: dict()})
+    for prefixes, clang_args, extra_commands, triple_in_cmd in run_list:
+      if args.verbose:
+        print('Extracted clang cmd: clang {}'.format(clang_args), file=sys.stderr)
+        print('Extracted FileCheck prefixes: {}'.format(prefixes), file=sys.stderr)
+
+      get_function_body(args, filename, clang_args, extra_commands, prefixes, triple_in_cmd, func_dict)
+
+      # Invoke c-index-test to get mapping from start lines to mangled names.
+      # Forward all clang args for now.
+      for k, v in get_line2spell_and_mangled(args, clang_args).items():
+        line2spell_and_mangled_list[k].append(v)
+
+    output_lines = [autogenerated_note]
+    for idx, line in enumerate(input_lines):
+      # Discard any previous script advertising.
+      if line.startswith(ADVERT):
+        continue
+      if idx in line2spell_and_mangled_list:
+        added = set()
+        for spell, mangled in line2spell_and_mangled_list[idx]:
+          # One line may contain multiple function declarations.
+          # Skip if the mangled name has been added before.
+          # The line number may come from an included file,
+          # we simply require the spelling name to appear on the line
+          # to exclude functions from other files.
+          if mangled in added or spell not in line:
+            continue
+          if args.functions is None or any(re.search(regex, spell) for regex in args.functions):
+            if added:
+              output_lines.append('//')
+            added.add(mangled)
+            common.add_ir_checks(output_lines, '//', run_list, func_dict, mangled, False)
+      output_lines.append(line.rstrip('\n'))
+
+    # Update the test file.
+    with open(filename, 'w') as f:
+      for line in output_lines:
+        f.write(line + '\n')
+
+  return 0
+
+
+if __name__ == '__main__':
+  sys.exit(main())