"""Disassembler of Python byte code into mnemonics.""" import sys import string import types __all__ = ["dis","disassemble","distb","disco","opname","cmp_op", "hasconst","hasname","hasjrel","hasjabs","haslocal", "hascompare"] def dis(x=None): """Disassemble classes, methods, functions, or code. With no argument, disassemble the last traceback. """ if not x: distb() return if type(x) is types.InstanceType: x = x.__class__ if hasattr(x, 'im_func'): x = x.im_func if hasattr(x, 'func_code'): x = x.func_code if hasattr(x, '__dict__'): items = x.__dict__.items() items.sort() for name, x1 in items: if type(x1) in (types.MethodType, types.FunctionType, types.CodeType): print "Disassembly of %s:" % name try: dis(x1) except TypeError, msg: print "Sorry:", msg print elif hasattr(x, 'co_code'): disassemble(x) else: raise TypeError, \ "don't know how to disassemble %s objects" % \ type(x).__name__ def distb(tb=None): """Disassemble a traceback (default: last traceback).""" if not tb: try: tb = sys.last_traceback except AttributeError: raise RuntimeError, "no last traceback to disassemble" while tb.tb_next: tb = tb.tb_next disassemble(tb.tb_frame.f_code, tb.tb_lasti) def disassemble(co, lasti=-1): """Disassemble a code object.""" code = co.co_code labels = findlabels(code) n = len(code) i = 0 extended_arg = 0 while i < n: c = code[i] op = ord(c) if op == SET_LINENO and i > 0: print # Extra blank line if i == lasti: print '-->', else: print ' ', if i in labels: print '>>', else: print ' ', print string.rjust(`i`, 4), print string.ljust(opname[op], 20), i = i+1 if op >= HAVE_ARGUMENT: oparg = ord(code[i]) + ord(code[i+1])*256 + extended_arg extended_arg = 0 i = i+2 if op == EXTENDED_ARG: extended_arg = oparg*65536L print string.rjust(`oparg`, 5), if op in hasconst: print '(' + `co.co_consts[oparg]` + ')', elif op in hasname: print '(' + co.co_names[oparg] + ')', elif op in hasjrel: print '(to ' + `i + oparg` + ')', elif op in haslocal: print '(' + co.co_varnames[oparg] + ')', elif op in hascompare: print '(' + cmp_op[oparg] + ')', print disco = disassemble # XXX For backwards compatibility def findlabels(code): """Detect all offsets in a byte code which are jump targets. Return the list of offsets. """ labels = [] n = len(code) i = 0 while i < n: c = code[i] op = ord(c) i = i+1 if op >= HAVE_ARGUMENT: oparg = ord(code[i]) + ord(code[i+1])*256 i = i+2 label = -1 if op in hasjrel: label = i+oparg elif op in hasjabs: label = oparg if label >= 0: if label not in labels: labels.append(label) return labels cmp_op = ('<', '<=', '==', '!=', '>', '>=', 'in', 'not in', 'is', 'is not', 'exception match', 'BAD') hasconst = [] hasname = [] hasjrel = [] hasjabs = [] haslocal = [] hascompare = [] opname = [''] * 256 for op in range(256): opname[op] = '<' + `op` + '>' def def_op(name, op): opname[op] = name def name_op(name, op): opname[op] = name hasname.append(op) def jrel_op(name, op): opname[op] = name hasjrel.append(op) def jabs_op(name, op): opname[op] = name hasjabs.append(op) # Instruction opcodes for compiled code def_op('STOP_CODE', 0) def_op('POP_TOP', 1) def_op('ROT_TWO', 2) def_op('ROT_THREE', 3) def_op('DUP_TOP', 4) def_op('ROT_FOUR', 5) def_op('UNARY_POSITIVE', 10) def_op('UNARY_NEGATIVE', 11) def_op('UNARY_NOT', 12) def_op('UNARY_CONVERT', 13) def_op('UNARY_INVERT', 15) def_op('BINARY_POWER', 19) def_op('BINARY_MULTIPLY', 20) def_op('BINARY_DIVIDE', 21) def_op('BINARY_MODULO', 22) def_op('BINARY_ADD', 23) def_op('BINARY_SUBTRACT', 24) def_op('BINARY_SUBSCR', 25) def_op('SLICE+0', 30) def_op('SLICE+1', 31) def_op('SLICE+2', 32) def_op('SLICE+3', 33) def_op('STORE_SLICE+0', 40) def_op('STORE_SLICE+1', 41) def_op('STORE_SLICE+2', 42) def_op('STORE_SLICE+3', 43) def_op('DELETE_SLICE+0', 50) def_op('DELETE_SLICE+1', 51) def_op('DELETE_SLICE+2', 52) def_op('DELETE_SLICE+3', 53) def_op('INPLACE_ADD', 55) def_op('INPLACE_SUBTRACT', 56) def_op('INPLACE_MULTIPLY', 57) def_op('INPLACE_DIVIDE', 58) def_op('INPLACE_MODULO', 59) def_op('STORE_SUBSCR', 60) def_op('DELETE_SUBSCR', 61) def_op('BINARY_LSHIFT', 62) def_op('BINARY_RSHIFT', 63) def_op('BINARY_AND', 64) def_op('BINARY_XOR', 65) def_op('BINARY_OR', 66) def_op('INPLACE_POWER', 67) def_op('PRINT_EXPR', 70) def_op('PRINT_ITEM', 71) def_op('PRINT_NEWLINE', 72) def_op('PRINT_ITEM_TO', 73) def_op('PRINT_NEWLINE_TO', 74) def_op('INPLACE_LSHIFT', 75) def_op('INPLACE_RSHIFT', 76) def_op('INPLACE_AND', 77) def_op('INPLACE_XOR', 78) def_op('INPLACE_OR', 79) def_op('BREAK_LOOP', 80) def_op('LOAD_LOCALS', 82) def_op('RETURN_VALUE', 83) def_op('IMPORT_STAR', 84) def_op('EXEC_STMT', 85) def_op('POP_BLOCK', 87) def_op('END_FINALLY', 88) def_op('BUILD_CLASS', 89) HAVE_ARGUMENT = 90 # Opcodes from here have an argument: name_op('STORE_NAME', 90) # Index in name list name_op('DELETE_NAME', 91) # "" def_op('UNPACK_SEQUENCE', 92) # Number of tuple items name_op('STORE_ATTR', 95) # Index in name list name_op('DELETE_ATTR', 96) # "" name_op('STORE_GLOBAL', 97) # "" name_op('DELETE_GLOBAL', 98) # "" def_op('DUP_TOPX', 99) # number of items to duplicate def_op('LOAD_CONST', 100) # Index in const list hasconst.append(100) name_op('LOAD_NAME', 101) # Index in name list def_op('BUILD_TUPLE', 102) # Number of tuple items def_op('BUILD_LIST', 103) # Number of list items def_op('BUILD_MAP', 104) # Always zero for now name_op('LOAD_ATTR', 105) # Index in name list def_op('COMPARE_OP', 106) # Comparison operator hascompare.append(106) name_op('IMPORT_NAME', 107) # Index in name list name_op('IMPORT_FROM', 108) # Index in name list jrel_op('JUMP_FORWARD', 110) # Number of bytes to skip jrel_op('JUMP_IF_FALSE', 111) # "" jrel_op('JUMP_IF_TRUE', 112) # "" jabs_op('JUMP_ABSOLUTE', 113) # Target byte offset from beginning of code jrel_op('FOR_LOOP', 114) # Number of bytes to skip name_op('LOAD_GLOBAL', 116) # Index in name list jrel_op('SETUP_LOOP', 120) # Distance to target address jrel_op('SETUP_EXCEPT', 121) # "" jrel_op('SETUP_FINALLY', 122) # "" def_op('LOAD_FAST', 124) # Local variable number haslocal.append(124) def_op('STORE_FAST', 125) # Local variable number haslocal.append(125) def_op('DELETE_FAST', 126) # Local variable number haslocal.append(126) def_op('SET_LINENO', 127) # Current line number SET_LINENO = 127 def_op('RAISE_VARARGS', 130) # Number of raise arguments (1, 2, or 3) def_op('CALL_FUNCTION', 131) # #args + (#kwargs << 8) def_op('MAKE_FUNCTION', 132) # Number of args with default values def_op('BUILD_SLICE', 133) # Number of items def_op('CALL_FUNCTION_VAR', 140) # #args + (#kwargs << 8) def_op('CALL_FUNCTION_KW', 141) # #args + (#kwargs << 8) def_op('CALL_FUNCTION_VAR_KW', 142) # #args + (#kwargs << 8) def_op('EXTENDED_ARG', 143) EXTENDED_ARG = 143 def _test(): """Simple test program to disassemble a file.""" if sys.argv[1:]: if sys.argv[2:]: sys.stderr.write("usage: python dis.py [-|file]\n") sys.exit(2) fn = sys.argv[1] if not fn or fn == "-": fn = None else: fn = None if not fn: f = sys.stdin else: f = open(fn) source = f.read() if fn: f.close() else: fn = "" code = compile(source, fn, "exec") dis(code) if __name__ == "__main__": _test()