utils/benchmark/tools/strip_asm.py

   1 #!/usr/bin/env python
   2
   3 """
   4 strip_asm.py - Cleanup ASM output for the specified file
   5 """
   6
   7 from argparse import ArgumentParser
   8 import sys
   9 import os
  10 import re
  11
  12 def find_used_labels(asm):
  13     found = set()
  14     label_re = re.compile("\s*j[a-z]+\s+\.L([a-zA-Z0-9][a-zA-Z0-9_]*)")
  15     for l in asm.splitlines():
  16         m = label_re.match(l)
  17         if m:
  18             found.add('.L%s' % m.group(1))
  19     return found
  20
  21
  22 def normalize_labels(asm):
  23     decls = set()
  24     label_decl = re.compile("^[.]{0,1}L([a-zA-Z0-9][a-zA-Z0-9_]*)(?=:)")
  25     for l in asm.splitlines():
  26         m = label_decl.match(l)
  27         if m:
  28             decls.add(m.group(0))
  29     if len(decls) == 0:
  30         return asm
  31     needs_dot = next(iter(decls))[0] != '.'
  32     if not needs_dot:
  33         return asm
  34     for ld in decls:
  35         asm = re.sub("(^|\s+)" + ld + "(?=:|\s)", '\\1.' + ld, asm)
  36     return asm
  37
  38
  39 def transform_labels(asm):
  40     asm = normalize_labels(asm)
  41     used_decls = find_used_labels(asm)
  42     new_asm = ''
  43     label_decl = re.compile("^\.L([a-zA-Z0-9][a-zA-Z0-9_]*)(?=:)")
  44     for l in asm.splitlines():
  45         m = label_decl.match(l)
  46         if not m or m.group(0) in used_decls:
  47             new_asm += l
  48             new_asm += '\n'
  49     return new_asm
  50
  51
  52 def is_identifier(tk):
  53     if len(tk) == 0:
  54         return False
  55     first = tk[0]
  56     if not first.isalpha() and first != '_':
  57         return False
  58     for i in range(1, len(tk)):
  59         c = tk[i]
  60         if not c.isalnum() and c != '_':
  61             return False
  62     return True
  63
  64 def process_identifiers(l):
  65     """
  66     process_identifiers - process all identifiers and modify them to have
  67     consistent names across all platforms; specifically across ELF and MachO.
  68     For example, MachO inserts an additional understore at the beginning of
  69     names. This function removes that.
  70     """
  71     parts = re.split(r'([a-zA-Z0-9_]+)', l)
  72     new_line = ''
  73     for tk in parts:
  74         if is_identifier(tk):
  75             if tk.startswith('__Z'):
  76                 tk = tk[1:]
  77             elif tk.startswith('_') and len(tk) > 1 and \
  78                     tk[1].isalpha() and tk[1] != 'Z':
  79                 tk = tk[1:]
  80         new_line += tk
  81     return new_line
  82
  83
  84 def process_asm(asm):
  85     """
  86     Strip the ASM of unwanted directives and lines
  87     """
  88     new_contents = ''
  89     asm = transform_labels(asm)
  90
  91     # TODO: Add more things we want to remove
  92     discard_regexes = [
  93         re.compile("\s+\..*$"), # directive
  94         re.compile("\s*#(NO_APP|APP)$"), #inline ASM
  95         re.compile("\s*#.*$"), # comment line
  96         re.compile("\s*\.globa?l\s*([.a-zA-Z_][a-zA-Z0-9$_.]*)"), #global directive
  97         re.compile("\s*\.(string|asciz|ascii|[1248]?byte|short|word|long|quad|value|zero)"),
  98     ]
  99     keep_regexes = [
 100
 101     ]
 102     fn_label_def = re.compile("^[a-zA-Z_][a-zA-Z0-9_.]*:")
 103     for l in asm.splitlines():
 104         # Remove Mach-O attribute
 105         l = l.replace('@GOTPCREL', '')
 106         add_line = True
 107         for reg in discard_regexes:
 108             if reg.match(l) is not None:
 109                 add_line = False
 110                 break
 111         for reg in keep_regexes:
 112             if reg.match(l) is not None:
 113                 add_line = True
 114                 break
 115         if add_line:
 116             if fn_label_def.match(l) and len(new_contents) != 0:
 117                 new_contents += '\n'
 118             l = process_identifiers(l)
 119             new_contents += l
 120             new_contents += '\n'
 121     return new_contents
 122
 123 def main():
 124     parser = ArgumentParser(
 125         description='generate a stripped assembly file')
 126     parser.add_argument(
 127         'input', metavar='input', type=str, nargs=1,
 128         help='An input assembly file')
 129     parser.add_argument(
 130         'out', metavar='output', type=str, nargs=1,
 131         help='The output file')
 132     args, unknown_args = parser.parse_known_args()
 133     input = args.input[0]
 134     output = args.out[0]
 135     if not os.path.isfile(input):
 136         print(("ERROR: input file '%s' does not exist") % input)
 137         sys.exit(1)
 138     contents = None
 139     with open(input, 'r') as f:
 140         contents = f.read()
 141     new_contents = process_asm(contents)
 142     with open(output, 'w') as f:
 143         f.write(new_contents)
 144
 145
 146 if __name__ == '__main__':
 147     main()
 148
 149 # vim: tabstop=4 expandtab shiftwidth=4 softtabstop=4
 150 # kate: tab-width: 4; replace-tabs on; indent-width 4; tab-indents: off;
 151 # kate: indent-mode python; remove-trailing-spaces modified;