text: #!/usr/bin/env python2.7
  
  """A test case update script.
  
  This script is a utility to update LLVM X86 'llc' based test cases with new
  FileCheck patterns. It can either update all of the tests in the file or
  a single test function.
  """
  
  import argparse
  import os         # Used to advertise this file's name ("autogenerated_note").
  import string
  import subprocess
  import sys
  import re
  
  # Invoke the tool that is being tested.
  def llc(args, cmd_args, ir):
    with open(ir) as ir_file:
      stdout = subprocess.check_output(args.llc_binary + ' ' + cmd_args,
                                       shell=True, stdin=ir_file)
    # Fix line endings to unix CR style.
    stdout = stdout.replace('\r\n', '\n')
    return stdout
  
  
  # RegEx: this is where the magic happens.
  
  ASM_FUNCTION_X86_RE = re.compile(
      r'^_?(?P<func>[^:]+):[ \t]*#+[ \t]*@(?P=func)\n[^:]*?'
      r'(?P<body>^##?[ \t]+[^:]+:.*?)\s*'
      r'^\s*(?:[^:\n]+?:\s*\n\s*\.size|\.cfi_endproc|\.globl|\.comm|\.(?:sub)?section|#+ -- End function)',
      flags=(re.M | re.S))
  
  ASM_FUNCTION_ARM_RE = re.compile(
          r'^(?P<func>[0-9a-zA-Z_]+):\n' # f: (name of function)
          r'\s+\.fnstart\n' # .fnstart
          r'(?P<body>.*?)\n' # (body of the function)
          r'.Lfunc_end[0-9]+:', # .Lfunc_end0: or # -- End function
          flags=(re.M | re.S))
  
  ASM_FUNCTION_AARCH64_RE = re.compile(
       r'^_?(?P<func>[^:]+):[ \t]*\/\/[ \t]*@(?P=func)\n'
       r'[ \t]+.cfi_startproc\n'
       r'(?P<body>.*?)\n'
       # This list is incomplete
       r'.Lfunc_end[0-9]+:\n',
       flags=(re.M | re.S))
  
  ASM_FUNCTION_MIPS_RE = re.compile(
      r'^_?(?P<func>[^:]+):[ \t]*#+[ \t]*@(?P=func)\n[^:]*?' # f: (name of func)
      r'(?:^[ \t]+\.(frame|f?mask|set).*?\n)+'  # Mips+LLVM standard asm prologue
      r'(?P<body>.*?)\n'                        # (body of the function)
      r'(?:^[ \t]+\.(set|end).*?\n)+'           # Mips+LLVM standard asm epilogue
      r'(\$|\.L)func_end[0-9]+:\n',             # $func_end0: (mips32 - O32) or
                                                # .Lfunc_end0: (mips64 - NewABI)
      flags=(re.M | re.S))
  
  ASM_FUNCTION_PPC_RE = re.compile(
      r'^_?(?P<func>[^:]+):[ \t]*#+[ \t]*@(?P=func)\n'
      r'\.Lfunc_begin[0-9]+:\n'
      r'[ \t]+.cfi_startproc\n'
      r'(?:\.Lfunc_[gl]ep[0-9]+:\n(?:[ \t]+.*?\n)*)*'
      r'(?P<body>.*?)\n'
      # This list is incomplete
      r'(?:^[ \t]*(?:\.long[ \t]+[^\n]+|\.quad[ \t]+[^\n]+)\n)*'
      r'.Lfunc_end[0-9]+:\n',
      flags=(re.M | re.S))
  
  ASM_FUNCTION_RISCV_RE = re.compile(
      r'^_?(?P<func>[^:]+):[ \t]*#+[ \t]*@(?P=func)\n[^:]*?'
      r'(?P<body>^##?[ \t]+[^:]+:.*?)\s*'
      r'.Lfunc_end[0-9]+:\n',
      flags=(re.M | re.S))
  
  ASM_FUNCTION_SYSTEMZ_RE = re.compile(
      r'^_?(?P<func>[^:]+):[ \t]*#+[ \t]*@(?P=func)\n'
      r'[ \t]+.cfi_startproc\n'
      r'(?P<body>.*?)\n'
      r'.Lfunc_end[0-9]+:\n',
      flags=(re.M | re.S))
  
  
  SCRUB_WHITESPACE_RE = re.compile(r'(?!^(|  \w))[ \t]+', flags=re.M)
  SCRUB_TRAILING_WHITESPACE_RE = re.compile(r'[ \t]+$', 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_X86_SHUFFLES_RE = (
      re.compile(
          r'^(\s*\w+) [^#\n]+#+ ((?:[xyz]mm\d+|mem)( \{%k\d+\}( \{z\})?)? = .*)$',
          flags=re.M))
  SCRUB_X86_SP_RE = re.compile(r'\d+\(%(esp|rsp)\)')
  SCRUB_X86_RIP_RE = re.compile(r'[.\w]+\(%rip\)')
  SCRUB_X86_LCP_RE = re.compile(r'\.LCPI[0-9]+_[0-9]+')
  SCRUB_X86_RET_RE = re.compile(r'ret[l|q]')
  
  RUN_LINE_RE = re.compile('^\s*;\s*RUN:\s*(.*)$')
  TRIPLE_ARG_RE = re.compile(r'-mtriple=([^ ]+)')
  TRIPLE_IR_RE = re.compile(r'^target\s+triple\s*=\s*"([^"]+)"$')
  IR_FUNCTION_RE = re.compile('^\s*define\s+(?:internal\s+)?[^@]*@(\w+)\s*\(')
  CHECK_PREFIX_RE = re.compile('--?check-prefix(?:es)?=(\S+)')
  CHECK_RE = re.compile(r'^\s*;\s*([^:]+?)(?:-NEXT|-NOT|-DAG|-LABEL)?:')
  
  def scrub_asm_x86(asm, args):
    # Scrub runs of whitespace out of the assembly, but leave the leading
    # whitespace in place.
    asm = SCRUB_WHITESPACE_RE.sub(r' ', asm)
    # Expand the tabs used for indentation.
    asm = string.expandtabs(asm, 2)
    # Detect shuffle asm comments and hide the operands in favor of the comments.
    asm = SCRUB_X86_SHUFFLES_RE.sub(r'\1 {{.*#+}} \2', asm)
    # Generically match the stack offset of a memory operand.
    asm = SCRUB_X86_SP_RE.sub(r'{{[0-9]+}}(%\1)', asm)
    # Generically match a RIP-relative memory operand.
    asm = SCRUB_X86_RIP_RE.sub(r'{{.*}}(%rip)', asm)
    # Generically match a LCP symbol.
    asm = SCRUB_X86_LCP_RE.sub(r'{{\.LCPI.*}}', asm)
    if args.x86_extra_scrub:
      # Avoid generating different checks for 32- and 64-bit because of 'retl' vs 'retq'.
      asm = SCRUB_X86_RET_RE.sub(r'ret{{[l|q]}}', asm)
    # Strip kill operands inserted into the asm.
    asm = SCRUB_KILL_COMMENT_RE.sub('', asm)
    # Strip trailing whitespace.
    asm = SCRUB_TRAILING_WHITESPACE_RE.sub(r'', asm)
    return asm
  
  def scrub_asm_arm_eabi(asm, args):
    # Scrub runs of whitespace out of the assembly, but leave the leading
    # whitespace in place.
    asm = SCRUB_WHITESPACE_RE.sub(r' ', asm)
    # Expand the tabs used for indentation.
    asm = string.expandtabs(asm, 2)
    # Strip kill operands inserted into the asm.
    asm = SCRUB_KILL_COMMENT_RE.sub('', asm)
    # Strip trailing whitespace.
    asm = SCRUB_TRAILING_WHITESPACE_RE.sub(r'', asm)
    return asm
  
  def scrub_asm_powerpc64(asm, args):
    # Scrub runs of whitespace out of the assembly, but leave the leading
    # whitespace in place.
    asm = SCRUB_WHITESPACE_RE.sub(r' ', asm)
    # Expand the tabs used for indentation.
    asm = string.expandtabs(asm, 2)
    # Stripe unimportant comments
    asm = SCRUB_LOOP_COMMENT_RE.sub(r'', asm)
    # Strip trailing whitespace.
    asm = SCRUB_TRAILING_WHITESPACE_RE.sub(r'', asm)
    return asm
  
  def scrub_asm_mips(asm, args):
    # Scrub runs of whitespace out of the assembly, but leave the leading
    # whitespace in place.
    asm = SCRUB_WHITESPACE_RE.sub(r' ', asm)
    # Expand the tabs used for indentation.
    asm = string.expandtabs(asm, 2)
    # Strip trailing whitespace.
    asm = SCRUB_TRAILING_WHITESPACE_RE.sub(r'', asm)
    return asm
  
  def scrub_asm_riscv(asm, args):
    # Scrub runs of whitespace out of the assembly, but leave the leading
    # whitespace in place.
    asm = SCRUB_WHITESPACE_RE.sub(r' ', asm)
    # Expand the tabs used for indentation.
    asm = string.expandtabs(asm, 2)
    # Strip trailing whitespace.
    asm = SCRUB_TRAILING_WHITESPACE_RE.sub(r'', asm)
    return asm
  
  def scrub_asm_systemz(asm, args):
    # Scrub runs of whitespace out of the assembly, but leave the leading
    # whitespace in place.
    asm = SCRUB_WHITESPACE_RE.sub(r' ', asm)
    # Expand the tabs used for indentation.
    asm = string.expandtabs(asm, 2)
    # Strip trailing whitespace.
    asm = SCRUB_TRAILING_WHITESPACE_RE.sub(r'', asm)
    return asm
  
  
  # Build up a dictionary of all the function bodies.
  def build_function_body_dictionary(raw_tool_output, triple, prefixes, func_dict,
                                     args):
    target_handlers = {
        'x86_64': (scrub_asm_x86, ASM_FUNCTION_X86_RE),
        'i686': (scrub_asm_x86, ASM_FUNCTION_X86_RE),
        'x86': (scrub_asm_x86, ASM_FUNCTION_X86_RE),
        'i386': (scrub_asm_x86, ASM_FUNCTION_X86_RE),
        'aarch64': (scrub_asm_arm_eabi, ASM_FUNCTION_AARCH64_RE),
        'arm-eabi': (scrub_asm_arm_eabi, ASM_FUNCTION_ARM_RE),
        'thumb-eabi': (scrub_asm_arm_eabi, ASM_FUNCTION_ARM_RE),
        'thumbv6': (scrub_asm_arm_eabi, ASM_FUNCTION_ARM_RE),
        'thumbv6-eabi': (scrub_asm_arm_eabi, ASM_FUNCTION_ARM_RE),
        'thumbv6t2': (scrub_asm_arm_eabi, ASM_FUNCTION_ARM_RE),
        'thumbv6t2-eabi': (scrub_asm_arm_eabi, ASM_FUNCTION_ARM_RE),
        'thumbv6m': (scrub_asm_arm_eabi, ASM_FUNCTION_ARM_RE),
        'thumbv6m-eabi': (scrub_asm_arm_eabi, ASM_FUNCTION_ARM_RE),
        'thumbv7': (scrub_asm_arm_eabi, ASM_FUNCTION_ARM_RE),
        'thumbv7-eabi': (scrub_asm_arm_eabi, ASM_FUNCTION_ARM_RE),
        'thumbv7m': (scrub_asm_arm_eabi, ASM_FUNCTION_ARM_RE),
        'thumbv7m-eabi': (scrub_asm_arm_eabi, ASM_FUNCTION_ARM_RE),
        'thumbv8-eabi': (scrub_asm_arm_eabi, ASM_FUNCTION_ARM_RE),
        'thumbv8m.base': (scrub_asm_arm_eabi, ASM_FUNCTION_ARM_RE),
        'thumbv8m.main': (scrub_asm_arm_eabi, ASM_FUNCTION_ARM_RE),
        'armv6': (scrub_asm_arm_eabi, ASM_FUNCTION_ARM_RE),
        'armv7': (scrub_asm_arm_eabi, ASM_FUNCTION_ARM_RE),
        'armv7-eabi': (scrub_asm_arm_eabi, ASM_FUNCTION_ARM_RE),
        'armeb-eabi': (scrub_asm_arm_eabi, ASM_FUNCTION_ARM_RE),
        'armv7eb-eabi': (scrub_asm_arm_eabi, ASM_FUNCTION_ARM_RE),
        'armv7eb': (scrub_asm_arm_eabi, ASM_FUNCTION_ARM_RE),
        'mips': (scrub_asm_mips, ASM_FUNCTION_MIPS_RE),
        'powerpc64': (scrub_asm_powerpc64, ASM_FUNCTION_PPC_RE),
        'powerpc64le': (scrub_asm_powerpc64, ASM_FUNCTION_PPC_RE),
        'riscv32': (scrub_asm_riscv, ASM_FUNCTION_RISCV_RE),
        'riscv64': (scrub_asm_riscv, ASM_FUNCTION_RISCV_RE),
        's390x': (scrub_asm_systemz, ASM_FUNCTION_SYSTEMZ_RE),
    }
    handlers = None
    for prefix, s in target_handlers.items():
      if triple.startswith(prefix):
        handlers = s
        break
    else:
      raise KeyError('Triple %r is not supported' % (triple))
  
    scrubber, function_re = handlers
    for m in function_re.finditer(raw_tool_output):
      if not m:
        continue
      func = m.group('func')
      scrubbed_body = scrubber(m.group('body'), args)
      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 args.verbose:
        print >>sys.stderr, 'Processing function: ' + func
        for l in scrubbed_body.splitlines():
          print >>sys.stderr, '  ' + l
      for prefix in prefixes:
        if func in func_dict[prefix] and func_dict[prefix][func] != scrubbed_body:
          if prefix == prefixes[-1]:
            print >>sys.stderr, ('WARNING: Found conflicting asm under the '
                                 'same prefix: %r!' % (prefix,))
          else:
            func_dict[prefix][func] = None
            continue
  
        func_dict[prefix][func] = scrubbed_body
  
  
  def add_checks(output_lines, run_list, func_dict, func_name):
    printed_prefixes = []
    for p in run_list:
      checkprefixes = p[0]
      for checkprefix in checkprefixes:
        if checkprefix in printed_prefixes:
          break
        if not func_dict[checkprefix][func_name]:
          continue
        # Add some space between different check prefixes.
        if len(printed_prefixes) != 0:
          output_lines.append(';')
        printed_prefixes.append(checkprefix)
        output_lines.append('; %s-LABEL: %s:' % (checkprefix, func_name))
        func_body = func_dict[checkprefix][func_name].splitlines()
        output_lines.append('; %s:       %s' % (checkprefix, func_body[0]))
        for func_line in func_body[1:]:
          output_lines.append('; %s-NEXT:  %s' % (checkprefix, func_line))
        # Add space between different check prefixes and the first line of code.
        # output_lines.append(';')
        break
    return output_lines
  
  
  def should_add_line_to_output(input_line, prefix_set):
    # Skip any blank comment lines in the IR.
    if input_line.strip() == ';':
      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:
      return False
  
    return True
  
  
  def main():
    parser = argparse.ArgumentParser(description=__doc__)
    parser.add_argument('-v', '--verbose', action='store_true',
                        help='Show verbose output')
    parser.add_argument('--llc-binary', default='llc',
                        help='The "llc" binary to use to generate the test case')
    parser.add_argument(
        '--function', help='The function in the test file to update')
    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('tests', nargs='+')
    args = parser.parse_args()
  
    autogenerated_note = ('; NOTE: Assertions have been autogenerated by '
                          'utils/' + os.path.basename(__file__))
  
    for test in args.tests:
      if args.verbose:
        print >>sys.stderr, 'Scanning for RUN lines in test file: %s' % (test,)
      with open(test) as f:
        input_lines = [l.rstrip() for l in f]
  
      triple_in_ir = None
      for l in input_lines:
        m = TRIPLE_IR_RE.match(l)
        if m:
          triple_in_ir = m.groups()[0]
          break
  
      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 >>sys.stderr, 'Found %d RUN lines:' % (len(run_lines),)
        for l in run_lines:
          print >>sys.stderr, '  RUN: ' + l
  
      run_list = []
      for l in run_lines:
        commands = [cmd.strip() for cmd in l.split('|', 1)]
        llc_cmd = commands[0]
  
        triple_in_cmd = None
        m = TRIPLE_ARG_RE.search(llc_cmd)
        if m:
          triple_in_cmd = m.groups()[0]
  
        filecheck_cmd = ''
        if len(commands) > 1:
          filecheck_cmd = commands[1]
        if not llc_cmd.startswith('llc '):
          print >>sys.stderr, 'WARNING: Skipping non-llc RUN line: ' + l
          continue
  
        if not filecheck_cmd.startswith('FileCheck '):
          print >>sys.stderr, 'WARNING: Skipping non-FileChecked RUN line: ' + l
          continue
  
        llc_cmd_args = llc_cmd[len('llc'):].strip()
        llc_cmd_args = llc_cmd_args.replace('< %s', '').replace('%s', '').strip()
  
        check_prefixes = [item for m in CHECK_PREFIX_RE.finditer(filecheck_cmd)
                                 for item in m.group(1).split(',')]
        if not check_prefixes:
          check_prefixes = ['CHECK']
  
        # FIXME: We should use multiple check prefixes to common check lines. For
        # now, we just ignore all but the last.
        run_list.append((check_prefixes, llc_cmd_args, triple_in_cmd))
  
      func_dict = {}
      for p in run_list:
        prefixes = p[0]
        for prefix in prefixes:
          func_dict.update({prefix: dict()})
      for prefixes, llc_args, triple_in_cmd in run_list:
        if args.verbose:
          print >>sys.stderr, 'Extracted LLC cmd: llc ' + llc_args
          print >>sys.stderr, 'Extracted FileCheck prefixes: ' + str(prefixes)
  
        raw_tool_output = llc(args, llc_args, test)
        if not (triple_in_cmd or triple_in_ir):
          print >>sys.stderr, "Cannot find a triple. Assume 'x86'"
  
        build_function_body_dictionary(raw_tool_output,
            triple_in_cmd or triple_in_ir or 'x86', prefixes, func_dict, args)
  
      is_in_function = False
      is_in_function_start = False
      func_name = None
      prefix_set = set([prefix for p in run_list for prefix in p[0]])
      if args.verbose:
        print >>sys.stderr, 'Rewriting FileCheck prefixes: %s' % (prefix_set,)
      output_lines = []
      output_lines.append(autogenerated_note)
  
      for input_line in input_lines:
        if is_in_function_start:
          if input_line == '':
            continue
          if input_line.lstrip().startswith(';'):
            m = CHECK_RE.match(input_line)
            if not m or m.group(1) not in prefix_set:
              output_lines.append(input_line)
              continue
  
          # Print out the various check lines here.
          output_lines = add_checks(output_lines, run_list, func_dict, func_name)
          is_in_function_start = False
  
        if is_in_function:
          if should_add_line_to_output(input_line, prefix_set) == True:
            # This input line of the function body will go as-is into the output.
            output_lines.append(input_line)
          else:
            continue
          if input_line.strip() == '}':
            is_in_function = False
          continue
  
        if input_line == autogenerated_note:
          continue
  
        # If it's outside a function, it just gets copied to the output.
        output_lines.append(input_line)
  
        m = IR_FUNCTION_RE.match(input_line)
        if not m:
          continue
        func_name = m.group(1)
        if args.function is not None and func_name != args.function:
          # When filtering on a specific function, skip all others.
          continue
        is_in_function = is_in_function_start = True
  
      if args.verbose:
        print>>sys.stderr, 'Writing %d lines to %s...' % (len(output_lines), test)
  
      with open(test, 'wb') as f:
        f.writelines([l + '\n' for l in output_lines])
  
  
  if __name__ == '__main__':
    main()
  