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Diffstat (limited to 'lib/pycparser/ply/ygen.py')
-rw-r--r-- | lib/pycparser/ply/ygen.py | 74 |
1 files changed, 74 insertions, 0 deletions
diff --git a/lib/pycparser/ply/ygen.py b/lib/pycparser/ply/ygen.py new file mode 100644 index 0000000..acf5ca1 --- /dev/null +++ b/lib/pycparser/ply/ygen.py @@ -0,0 +1,74 @@ +# ply: ygen.py +# +# This is a support program that auto-generates different versions of the YACC parsing +# function with different features removed for the purposes of performance. +# +# Users should edit the method LParser.parsedebug() in yacc.py. The source code +# for that method is then used to create the other methods. See the comments in +# yacc.py for further details. + +import os.path +import shutil + +def get_source_range(lines, tag): + srclines = enumerate(lines) + start_tag = '#--! %s-start' % tag + end_tag = '#--! %s-end' % tag + + for start_index, line in srclines: + if line.strip().startswith(start_tag): + break + + for end_index, line in srclines: + if line.strip().endswith(end_tag): + break + + return (start_index + 1, end_index) + +def filter_section(lines, tag): + filtered_lines = [] + include = True + tag_text = '#--! %s' % tag + for line in lines: + if line.strip().startswith(tag_text): + include = not include + elif include: + filtered_lines.append(line) + return filtered_lines + +def main(): + dirname = os.path.dirname(__file__) + shutil.copy2(os.path.join(dirname, 'yacc.py'), os.path.join(dirname, 'yacc.py.bak')) + with open(os.path.join(dirname, 'yacc.py'), 'r') as f: + lines = f.readlines() + + parse_start, parse_end = get_source_range(lines, 'parsedebug') + parseopt_start, parseopt_end = get_source_range(lines, 'parseopt') + parseopt_notrack_start, parseopt_notrack_end = get_source_range(lines, 'parseopt-notrack') + + # Get the original source + orig_lines = lines[parse_start:parse_end] + + # Filter the DEBUG sections out + parseopt_lines = filter_section(orig_lines, 'DEBUG') + + # Filter the TRACKING sections out + parseopt_notrack_lines = filter_section(parseopt_lines, 'TRACKING') + + # Replace the parser source sections with updated versions + lines[parseopt_notrack_start:parseopt_notrack_end] = parseopt_notrack_lines + lines[parseopt_start:parseopt_end] = parseopt_lines + + lines = [line.rstrip()+'\n' for line in lines] + with open(os.path.join(dirname, 'yacc.py'), 'w') as f: + f.writelines(lines) + + print('Updated yacc.py') + +if __name__ == '__main__': + main() + + + + + |