utils/update_test_checks.py - external/github.com/emscripten-core/emscripten-fastcomp - Git at Google

 #!/usr/bin/env python2.7

 """A script to generate FileCheck statements for regression tests.

 This script is a utility to update LLVM opt or llc test cases with new
 FileCheck patterns. It can either update all of the tests in the file or
 a single test function.

 Example usage:
 $ update_test_checks.py --tool=../bin/opt test/foo.ll

 Workflow:
 1. Make a compiler patch that requires updating some number of FileCheck lines
    in regression test files.
 2. Save the patch and revert it from your local work area.
 3. Update the RUN-lines in the affected regression tests to look canonical.
    Example: "; RUN: opt < %s -instcombine -S | FileCheck %s"
 4. Refresh the FileCheck lines for either the entire file or select functions by
    running this script.
 5. Commit the fresh baseline of checks.
 6. Apply your patch from step 1 and rebuild your local binaries.
 7. Re-run this script on affected regression tests.
 8. Check the diffs to ensure the script has done something reasonable.
 9. Submit a patch including the regression test diffs for review.

 A common pattern is to have the script insert complete checking of every
 instruction. Then, edit it down to only check the relevant instructions.
 The script is designed to make adding checks to a test case fast, it is *not*
 designed to be authoratitive about what constitutes a good test!
 """

 import argparse
 import itertools
 import os         # Used to advertise this file's name ("autogenerated_note").
 import string
 import subprocess
 import sys
 import tempfile
 import re

 ADVERT = '; NOTE: Assertions have been autogenerated by '

 # RegEx: this is where the magic happens.

 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]+$', flags=re.M)
 SCRUB_X86_SHUFFLES_RE = (
     re.compile(
         r'^(\s*\w+) [^#\n]+#+ ((?:[xyz]mm\d+|mem)( \{%k\d+\}( \{z\})?)? = .*)$',
         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_KILL_COMMENT_RE = re.compile(r'^ *#+ +kill:.*\n')
 SCRUB_IR_COMMENT_RE = re.compile(r'\s*;.*')

 RUN_LINE_RE = re.compile('^\s*;\s*RUN:\s*(.*)$')
 IR_FUNCTION_RE = re.compile('^\s*define\s+(?:internal\s+)?[^@]*@([\w-]+)\s*\(')
 LLC_FUNCTION_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)',
     flags=(re.M | re.S))
 OPT_FUNCTION_RE = re.compile(
     r'^\s*define\s+(?:internal\s+)?[^@]*@(?P<func>[\w-]+?)\s*\('
     r'(\s+)?[^)]*[^{]*\{\n(?P<body>.*?)^\}$',
     flags=(re.M | re.S))
 CHECK_PREFIX_RE = re.compile('--check-prefix=(\S+)')
 CHECK_RE = re.compile(r'^\s*;\s*([^:]+?)(?:-NEXT|-NOT|-DAG|-LABEL)?:')
 # Match things that look at identifiers, but only if they are followed by
 # spaces, commas, paren, or end of the string
 IR_VALUE_RE = re.compile(r'(\s+)%(.+?)([,\s\(\)]|\Z)')


 # Invoke the tool that is being tested.
 def invoke_tool(args, cmd_args, ir):
   with open(ir) as ir_file:
     stdout = subprocess.check_output(args.tool_binary + ' ' + cmd_args,
                                      shell=True, stdin=ir_file)
   # Fix line endings to unix CR style.
   stdout = stdout.replace('\r\n', '\n')
   return stdout


 # FIXME: Separate the x86-specific scrubbers, so this can be used for other targets.
 def scrub_asm(asm):
   # 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)
   # Strip kill operands inserted into the asm.
   asm = SCRUB_KILL_COMMENT_RE.sub('', asm)
   return asm


 def scrub_body(body, tool_basename):
   # 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 = string.expandtabs(body, 2)
   # Strip trailing whitespace.
   body = SCRUB_TRAILING_WHITESPACE_RE.sub(r'', body)
   if tool_basename == "llc":
     body = scrub_asm(body)
   return body


 # Build up a dictionary of all the function bodies.
 def build_function_body_dictionary(raw_tool_output, prefixes, func_dict, verbose, tool_basename):
   if tool_basename == "llc":
     func_regex = LLC_FUNCTION_RE
   else:
     func_regex = OPT_FUNCTION_RE
   for m in func_regex.finditer(raw_tool_output):
     if not m:
       continue
     func = m.group('func')
     scrubbed_body = scrub_body(m.group('body'), tool_basename)
     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 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


 # Create a FileCheck variable name based on an IR name.
 def get_value_name(var):
   if var.isdigit():
     var = 'TMP' + var
   var = var.replace('.', '_')
   return var.upper()


 # Create a FileCheck variable from regex.
 def get_value_definition(var):
   return '[[' + get_value_name(var) + ':%.*]]'


 # Use a FileCheck variable.
 def get_value_use(var):
   return '[[' + get_value_name(var) + ']]'

 # Replace IR value defs and uses with FileCheck variables.
 def genericize_check_lines(lines):
   # 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):
     var = match.group(2)
     if var in vars_seen:
       rv = get_value_use(var)
     else:
       vars_seen.add(var)
       rv = get_value_definition(var)
     # 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(3)

   vars_seen = set()
   lines_with_def = []

   for i, line in enumerate(lines):
     # An IR variable named '%.' matches the FileCheck regex string.
     line = line.replace('%.', '%dot')
     # Ignore any comments, since the check lines will too.
     scrubbed_line = SCRUB_IR_COMMENT_RE.sub(r'', line)
     lines[i] =  IR_VALUE_RE.sub(transform_line_vars, scrubbed_line)
   return lines


 def add_checks(output_lines, prefix_list, func_dict, func_name, tool_basename):
   # Select a label format based on the whether we're checking asm or IR.
   if tool_basename == "llc":
     check_label_format = "; %s-LABEL: %s:"
   else:
     check_label_format = "; %s-LABEL: @%s("

   printed_prefixes = []
   for checkprefixes, _ in prefix_list:
     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, but not after the last
       # check line (before the test code).
       #if len(printed_prefixes) != 0:
       #  output_lines.append(';')
       printed_prefixes.append(checkprefix)
       output_lines.append(check_label_format % (checkprefix, func_name))
       func_body = func_dict[checkprefix][func_name].splitlines()

       # For IR output, change all defs to FileCheck variables, so we're immune
       # to variable naming fashions.
       if tool_basename == "opt":
         func_body = genericize_check_lines(func_body)

       # 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' % (checkprefix, func_body[0]))
       #  is_blank_line = False

       # For llc tests, there may be asm directives between the label and the
       # first checked line (most likely that first checked line is "# BB#0").
       if tool_basename == "opt":
         is_blank_line = False
       else:
         is_blank_line = True;

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

         # Skip blank lines instead of checking them.
         if is_blank_line == True:
           output_lines.append('; %s:       %s' % (checkprefix, func_line))
         else:
           output_lines.append('; %s-NEXT:  %s' % (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(';')
       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():
   from argparse import RawTextHelpFormatter
   parser = argparse.ArgumentParser(description=__doc__, formatter_class=RawTextHelpFormatter)
   parser.add_argument('-v', '--verbose', action='store_true',
                       help='Show verbose output')
   parser.add_argument('--tool-binary', default='llc',
                       help='The tool used to generate the test case')
   parser.add_argument(
       '--function', help='The function in the test file to update')
   parser.add_argument('tests', nargs='+')
   args = parser.parse_args()

   autogenerated_note = (ADVERT + 'utils/' + os.path.basename(__file__))

   tool_basename = os.path.basename(args.tool_binary)
   if (tool_basename != "llc" and tool_basename != "opt"):
     print >>sys.stderr, 'ERROR: Unexpected tool name: ' + tool_basename
     sys.exit(1)

   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]

     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

     prefix_list = []
     for l in run_lines:
       (tool_cmd, filecheck_cmd) = tuple([cmd.strip() for cmd in l.split('|', 1)])

       if not tool_cmd.startswith(tool_basename + ' '):
         print >>sys.stderr, 'WARNING: Skipping non-%s RUN line: %s' % (tool_basename, l)
         continue

       if not filecheck_cmd.startswith('FileCheck '):
         print >>sys.stderr, 'WARNING: Skipping non-FileChecked RUN line: ' + l
         continue

       tool_cmd_args = tool_cmd[len(tool_basename):].strip()
       tool_cmd_args = tool_cmd_args.replace('< %s', '').replace('%s', '').strip()

       check_prefixes = [m.group(1)
                         for m in CHECK_PREFIX_RE.finditer(filecheck_cmd)]
       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.
       prefix_list.append((check_prefixes, tool_cmd_args))

     func_dict = {}
     for prefixes, _ in prefix_list:
       for prefix in prefixes:
         func_dict.update({prefix: dict()})
     for prefixes, tool_args in prefix_list:
       if args.verbose:
         print >>sys.stderr, 'Extracted tool cmd: ' + tool_basename + ' ' + tool_args
         print >>sys.stderr, 'Extracted FileCheck prefixes: ' + str(prefixes)

       raw_tool_output = invoke_tool(args, tool_args, test)
       build_function_body_dictionary(raw_tool_output, prefixes, func_dict, args.verbose, tool_basename)

     is_in_function = False
     is_in_function_start = False
     prefix_set = set([prefix for prefixes, _ in prefix_list for prefix in prefixes])
     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, prefix_list, func_dict, name, tool_basename)
         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.
           # Except make leading whitespace uniform: 2 spaces.
           input_line = SCRUB_LEADING_WHITESPACE_RE.sub(r'  ', input_line)
           output_lines.append(input_line)
         else:
           continue
         if input_line.strip() == '}':
           is_in_function = False
         continue

       # Discard any previous script advertising.
       if input_line.startswith(ADVERT):
         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
       name = m.group(1)
       if args.function is not None and 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()
	#!/usr/bin/env python2.7

	"""A script to generate FileCheck statements for regression tests.

	This script is a utility to update LLVM opt or llc test cases with new
	FileCheck patterns. It can either update all of the tests in the file or
	a single test function.

	Example usage:
	$ update_test_checks.py --tool=../bin/opt test/foo.ll

	Workflow:
	1. Make a compiler patch that requires updating some number of FileCheck lines
	in regression test files.
	2. Save the patch and revert it from your local work area.
	3. Update the RUN-lines in the affected regression tests to look canonical.
	Example: "; RUN: opt < %s -instcombine -S \| FileCheck %s"
	4. Refresh the FileCheck lines for either the entire file or select functions by
	running this script.
	5. Commit the fresh baseline of checks.
	6. Apply your patch from step 1 and rebuild your local binaries.
	7. Re-run this script on affected regression tests.
	8. Check the diffs to ensure the script has done something reasonable.
	9. Submit a patch including the regression test diffs for review.

	A common pattern is to have the script insert complete checking of every
	instruction. Then, edit it down to only check the relevant instructions.
	The script is designed to make adding checks to a test case fast, it is not
	designed to be authoratitive about what constitutes a good test!
	"""

	import argparse
	import itertools
	import os # Used to advertise this file's name ("autogenerated_note").
	import string
	import subprocess
	import sys
	import tempfile
	import re

	ADVERT = '; NOTE: Assertions have been autogenerated by '

	# RegEx: this is where the magic happens.

	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]+$', flags=re.M)
	SCRUB_X86_SHUFFLES_RE = (
	re.compile(
	r'^(\s\w+) [^#\n]+#+ ((?:[xyz]mm\d+\|mem)( \{%k\d+\}( \{z\})?)? = .)$',
	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_KILL_COMMENT_RE = re.compile(r'^ #+ +kill:.\n')
	SCRUB_IR_COMMENT_RE = re.compile(r'\s;.')

	RUN_LINE_RE = re.compile('^\s;\sRUN:\s(.)$')
	IR_FUNCTION_RE = re.compile('^\sdefine\s+(?:internal\s+)?[^@]@([\w-]+)\s*\(')
	LLC_FUNCTION_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)',
	flags=(re.M \| re.S))
	OPT_FUNCTION_RE = re.compile(
	r'^\sdefine\s+(?:internal\s+)?[^@]@(?P<func>[\w-]+?)\s*\('
	r'(\s+)?[^)][^{]\{\n(?P<body>.*?)^\}$',
	flags=(re.M \| re.S))
	CHECK_PREFIX_RE = re.compile('--check-prefix=(\S+)')
	CHECK_RE = re.compile(r'^\s;\s([^:]+?)(?:-NEXT\|-NOT\|-DAG\|-LABEL)?:')
	# Match things that look at identifiers, but only if they are followed by
	# spaces, commas, paren, or end of the string
	IR_VALUE_RE = re.compile(r'(\s+)%(.+?)([,\s\(\)]\|\Z)')


	# Invoke the tool that is being tested.
	def invoke_tool(args, cmd_args, ir):
	with open(ir) as ir_file:
	stdout = subprocess.check_output(args.tool_binary + ' ' + cmd_args,
	shell=True, stdin=ir_file)
	# Fix line endings to unix CR style.
	stdout = stdout.replace('\r\n', '\n')
	return stdout


	# FIXME: Separate the x86-specific scrubbers, so this can be used for other targets.
	def scrub_asm(asm):
	# 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)
	# Strip kill operands inserted into the asm.
	asm = SCRUB_KILL_COMMENT_RE.sub('', asm)
	return asm


	def scrub_body(body, tool_basename):
	# 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 = string.expandtabs(body, 2)
	# Strip trailing whitespace.
	body = SCRUB_TRAILING_WHITESPACE_RE.sub(r'', body)
	if tool_basename == "llc":
	body = scrub_asm(body)
	return body


	# Build up a dictionary of all the function bodies.
	def build_function_body_dictionary(raw_tool_output, prefixes, func_dict, verbose, tool_basename):
	if tool_basename == "llc":
	func_regex = LLC_FUNCTION_RE
	else:
	func_regex = OPT_FUNCTION_RE
	for m in func_regex.finditer(raw_tool_output):
	if not m:
	continue
	func = m.group('func')
	scrubbed_body = scrub_body(m.group('body'), tool_basename)
	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 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


	# Create a FileCheck variable name based on an IR name.
	def get_value_name(var):
	if var.isdigit():
	var = 'TMP' + var
	var = var.replace('.', '_')
	return var.upper()


	# Create a FileCheck variable from regex.
	def get_value_definition(var):
	return '[[' + get_value_name(var) + ':%.*]]'


	# Use a FileCheck variable.
	def get_value_use(var):
	return '[[' + get_value_name(var) + ']]'

	# Replace IR value defs and uses with FileCheck variables.
	def genericize_check_lines(lines):
	# 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):
	var = match.group(2)
	if var in vars_seen:
	rv = get_value_use(var)
	else:
	vars_seen.add(var)
	rv = get_value_definition(var)
	# 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(3)

	vars_seen = set()
	lines_with_def = []

	for i, line in enumerate(lines):
	# An IR variable named '%.' matches the FileCheck regex string.
	line = line.replace('%.', '%dot')
	# Ignore any comments, since the check lines will too.
	scrubbed_line = SCRUB_IR_COMMENT_RE.sub(r'', line)
	lines[i] = IR_VALUE_RE.sub(transform_line_vars, scrubbed_line)
	return lines


	def add_checks(output_lines, prefix_list, func_dict, func_name, tool_basename):
	# Select a label format based on the whether we're checking asm or IR.
	if tool_basename == "llc":
	check_label_format = "; %s-LABEL: %s:"
	else:
	check_label_format = "; %s-LABEL: @%s("

	printed_prefixes = []
	for checkprefixes, _ in prefix_list:
	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, but not after the last
	# check line (before the test code).
	#if len(printed_prefixes) != 0:
	# output_lines.append(';')
	printed_prefixes.append(checkprefix)
	output_lines.append(check_label_format % (checkprefix, func_name))
	func_body = func_dict[checkprefix][func_name].splitlines()

	# For IR output, change all defs to FileCheck variables, so we're immune
	# to variable naming fashions.
	if tool_basename == "opt":
	func_body = genericize_check_lines(func_body)

	# 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' % (checkprefix, func_body[0]))
	# is_blank_line = False

	# For llc tests, there may be asm directives between the label and the
	# first checked line (most likely that first checked line is "# BB#0").
	if tool_basename == "opt":
	is_blank_line = False
	else:
	is_blank_line = True;

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

	# Skip blank lines instead of checking them.
	if is_blank_line == True:
	output_lines.append('; %s: %s' % (checkprefix, func_line))
	else:
	output_lines.append('; %s-NEXT: %s' % (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(';')
	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():
	from argparse import RawTextHelpFormatter
	parser = argparse.ArgumentParser(description=__doc__, formatter_class=RawTextHelpFormatter)
	parser.add_argument('-v', '--verbose', action='store_true',
	help='Show verbose output')
	parser.add_argument('--tool-binary', default='llc',
	help='The tool used to generate the test case')
	parser.add_argument(
	'--function', help='The function in the test file to update')
	parser.add_argument('tests', nargs='+')
	args = parser.parse_args()

	autogenerated_note = (ADVERT + 'utils/' + os.path.basename(__file__))

	tool_basename = os.path.basename(args.tool_binary)
	if (tool_basename != "llc" and tool_basename != "opt"):
	print >>sys.stderr, 'ERROR: Unexpected tool name: ' + tool_basename
	sys.exit(1)

	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]

	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

	prefix_list = []
	for l in run_lines:
	(tool_cmd, filecheck_cmd) = tuple([cmd.strip() for cmd in l.split('\|', 1)])

	if not tool_cmd.startswith(tool_basename + ' '):
	print >>sys.stderr, 'WARNING: Skipping non-%s RUN line: %s' % (tool_basename, l)
	continue

	if not filecheck_cmd.startswith('FileCheck '):
	print >>sys.stderr, 'WARNING: Skipping non-FileChecked RUN line: ' + l
	continue

	tool_cmd_args = tool_cmd[len(tool_basename):].strip()
	tool_cmd_args = tool_cmd_args.replace('< %s', '').replace('%s', '').strip()

	check_prefixes = [m.group(1)
	for m in CHECK_PREFIX_RE.finditer(filecheck_cmd)]
	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.
	prefix_list.append((check_prefixes, tool_cmd_args))

	func_dict = {}
	for prefixes, _ in prefix_list:
	for prefix in prefixes:
	func_dict.update({prefix: dict()})
	for prefixes, tool_args in prefix_list:
	if args.verbose:
	print >>sys.stderr, 'Extracted tool cmd: ' + tool_basename + ' ' + tool_args
	print >>sys.stderr, 'Extracted FileCheck prefixes: ' + str(prefixes)

	raw_tool_output = invoke_tool(args, tool_args, test)
	build_function_body_dictionary(raw_tool_output, prefixes, func_dict, args.verbose, tool_basename)

	is_in_function = False
	is_in_function_start = False
	prefix_set = set([prefix for prefixes, _ in prefix_list for prefix in prefixes])
	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, prefix_list, func_dict, name, tool_basename)
	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.
	# Except make leading whitespace uniform: 2 spaces.
	input_line = SCRUB_LEADING_WHITESPACE_RE.sub(r' ', input_line)
	output_lines.append(input_line)
	else:
	continue
	if input_line.strip() == '}':
	is_in_function = False
	continue

	# Discard any previous script advertising.
	if input_line.startswith(ADVERT):
	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
	name = m.group(1)
	if args.function is not None and 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()