Files
python-uncompyle6/uncompyle6/scanners/scanner25.py
2015-12-15 12:10:03 -05:00

914 lines
38 KiB
Python

"""
Python 2.5 bytecode scanner/deparser
Copyright (c) 1999 John Aycock
Copyright (c) 2000-2002 by hartmut Goebel <h.goebel@crazy-compilers.com>
Copyright (c) 2005 by Dan Pascu <dan@windowmaker.org>
Copyright (c) 2015 by Rocky Bernstein
See main module for license.
This overlaps Python's 2.5's dis module, but it can be run from
Python3 and other versions of Python. Also, we save token information
for later use in deparsing.
"""
import types
from collections import namedtuple
from array import array
import dis
from uncompyle6.opcodes.opcode_25 import *
import uncompyle6.scanner as scan
class Scanner25(scan.Scanner):
def __init__(self):
self.Token = scan.Scanner.__init__(self, 2.5)
def disassemble(self, co, classname=None):
'''
Disassemble a code object, returning a list of 'Token'.
The main part of this procedure is modelled after
dis.disassemble().
'''
rv = []
customize = {}
Token = self.Token # shortcut
self.code = array('B', co.co_code)
for i in self.op_range(0, len(self.code)):
if self.code[i] in (RETURN_VALUE, END_FINALLY):
n = i + 1
self.code = array('B', co.co_code[:n])
# linestarts is a tuple of (offset, line number.
# Turn that in a has that we can index
self.linestarts = list(dis.findlinestarts(co))
linestartoffsets = {}
for offset, lineno in self.linestarts:
linestartoffsets[offset] = lineno
self.prev = [0]
# class and names
if classname:
classname = '_' + classname.lstrip('_') + '__'
def unmangle(name):
if name.startswith(classname) and name[-2:] != '__':
return name[len(classname) - 2:]
return name
free = [ unmangle(name) for name in (co.co_cellvars + co.co_freevars) ]
names = [ unmangle(name) for name in co.co_names ]
varnames = [ unmangle(name) for name in co.co_varnames ]
else:
free = co.co_cellvars + co.co_freevars
names = co.co_names
varnames = co.co_varnames
self.names = names
# list of instruction to remove/add or change to match with bytecode 2.7
self.toChange = []
self.restructBytecode()
codelen = len(self.code)
# mapping adresses of prev instru
for i in self.op_range(0, codelen):
op = self.code[i]
self.prev.append(i)
if self.op_hasArgument(op):
self.prev.append(i)
self.prev.append(i)
j = 0
linestarts = self.linestarts
self.lines = []
linetuple = namedtuple('linetuple', ['l_no', 'next'])
# linestarts is a tuple of (offset, line number).
# Turn that in a has that we can index
linestartoffsets = {}
for offset, lineno in linestarts:
linestartoffsets[offset] = lineno
(prev_start_byte, prev_line_no) = linestarts[0]
for (start_byte, line_no) in linestarts[1:]:
while j < start_byte:
self.lines.append(linetuple(prev_line_no, start_byte))
j += 1
prev_line_no = start_byte
while j < codelen:
self.lines.append(linetuple(prev_line_no, codelen))
j+=1
self.load_asserts = set()
for i in self.op_range(0, codelen):
if self.code[i] == PJIT and self.code[i+3] == LOAD_GLOBAL:
if names[self.get_argument(i+3)] == 'AssertionError':
self.load_asserts.add(i+3)
# self.lines contains (block,addrLastInstr)
cf = self.find_jump_targets(self.code)
# contains (code, [addrRefToCode])
last_stmt = self.next_stmt[0]
i = self.next_stmt[last_stmt]
replace = {}
while i < codelen-1:
if self.lines[last_stmt].next > i:
if self.code[last_stmt] == PRINT_ITEM:
if self.code[i] == PRINT_ITEM:
replace[i] = 'PRINT_ITEM_CONT'
elif self.code[i] == PRINT_NEWLINE:
replace[i] = 'PRINT_NEWLINE_CONT'
last_stmt = i
i = self.next_stmt[i]
imports = self.all_instr(0, codelen, (IMPORT_NAME, IMPORT_FROM, IMPORT_STAR))
if len(imports) > 1:
last_import = imports[0]
for i in imports[1:]:
if self.lines[last_import].next > i:
if self.code[last_import] == IMPORT_NAME == self.code[i]:
replace[i] = 'IMPORT_NAME_CONT'
last_import = i
extended_arg = 0
for offset in self.op_range(0, codelen):
op = self.code[offset]
op_name = opname[op]
oparg = None; pattr = None
if offset in cf:
k = 0
for j in cf[offset]:
rv.append(Token('COME_FROM', None, repr(j),
offset="%s_%d" % (offset, k) ))
k += 1
if self.op_hasArgument(op):
oparg = self.get_argument(offset) + extended_arg
extended_arg = 0
if op == EXTENDED_ARG:
raise NotImplementedError
extended_arg = oparg * scan.L65536
continue
if op in hasconst:
const = co.co_consts[oparg]
if isinstance(const, types.CodeType):
oparg = const
if const.co_name == '<lambda>':
assert op_name == 'LOAD_CONST'
op_name = 'LOAD_LAMBDA'
elif const.co_name == '<genexpr>':
op_name = 'LOAD_GENEXPR'
elif const.co_name == '<dictcomp>':
op_name = 'LOAD_DICTCOMP'
elif const.co_name == '<setcomp>':
op_name = 'LOAD_SETCOMP'
# verify uses 'pattr' for comparism, since 'attr'
# now holds Code(const) and thus can not be used
# for comparism (todo: think about changing this)
# pattr = 'code_object @ 0x%x %s->%s' %
# (id(const), const.co_filename, const.co_name)
pattr = '<code_object ' + const.co_name + '>'
else:
pattr = const
elif op in hasname:
pattr = names[oparg]
elif op in hasjrel:
pattr = repr(offset + 3 + oparg)
elif op in hasjabs:
pattr = repr(oparg)
elif op in haslocal:
pattr = varnames[oparg]
elif op in hascompare:
pattr = cmp_op[oparg]
elif op in hasfree:
pattr = free[oparg]
if offset in self.toChange:
if self.code[offset] == JA and self.code[oparg] == WITH_CLEANUP:
op_name = 'SETUP_WITH'
cf[oparg] = cf.get(oparg, []) + [offset]
if op in (BUILD_LIST, BUILD_TUPLE, BUILD_SLICE,
UNPACK_SEQUENCE,
MAKE_FUNCTION, CALL_FUNCTION, MAKE_CLOSURE,
CALL_FUNCTION_VAR, CALL_FUNCTION_KW,
CALL_FUNCTION_VAR_KW, DUP_TOPX, RAISE_VARARGS
):
# CE - Hack for >= 2.5
# Now all values loaded via LOAD_CLOSURE are packed into
# a tuple before calling MAKE_CLOSURE.
if op == BUILD_TUPLE and \
self.code[self.prev[offset]] == LOAD_CLOSURE:
continue
else:
op_name = '%s_%d' % (op_name, oparg)
if op != BUILD_SLICE:
customize[op_name] = oparg
elif op == JA:
target = self.get_target(offset)
if target < offset:
if offset in self.stmts and self.code[offset+3] not in (END_FINALLY, POP_BLOCK) \
and offset not in self.not_continue:
op_name = 'CONTINUE'
else:
op_name = 'JUMP_BACK'
elif op == LOAD_GLOBAL:
if offset in self.load_asserts:
op_name = 'LOAD_ASSERT'
elif op == RETURN_VALUE:
if offset in self.return_end_ifs:
op_name = 'RETURN_END_IF'
if offset in linestartoffsets:
linestart = linestartoffsets[offset]
else:
linestart = None
if offset not in replace:
rv.append(Token(op_name, oparg, pattr, offset, linestart))
else:
rv.append(Token(replace[offset], oparg, pattr, offset, linestart))
return rv, customize
def getOpcodeToDel(self, i):
'''
check validity of the opcode at position I and return a list of opcode to delete
'''
opcode = self.code[i]
opsize = self.op_size(opcode)
if i+opsize >= len(self.code):
return None
if opcode == EXTENDED_ARG:
raise NotImplementedError
# del POP_TOP
if opcode in (PJIF, PJIT, JA, JF):
toDel = []
# del POP_TOP
if self.code[i+opsize] == POP_TOP:
if self.code[i+opsize] == self.code[i+opsize+1] and self.code[i+opsize] == self.code[i+opsize+2] \
and opcode in (JF, JA) and self.code[i+opsize] != self.code[i+opsize+3]:
pass
else:
toDel += [i+opsize]
# conditional tuple
if self.code[i] == JA and self.code[i+opsize] == POP_TOP \
and self.code[i+opsize+1] == JA and self.code[i+opsize+4] == POP_BLOCK:
jmpabs1target = self.get_target(i)
jmpabs2target = self.get_target(i+opsize+1)
if jmpabs1target == jmpabs2target and self.code[jmpabs1target] == FOR_ITER:
destFor = self.get_target(jmpabs1target)
if destFor == i+opsize+4:
setupLoop = self.last_instr(0, jmpabs1target, SETUP_LOOP)
standarFor = self.last_instr(setupLoop, jmpabs1target, GET_ITER)
if standarFor is None:
self.restructJump(jmpabs1target, destFor+self.op_size(POP_BLOCK))
toDel += [setupLoop, i+opsize+1, i+opsize+4]
if len(toDel) > 0:
return toDel
return None
if opcode == RAISE_VARARGS:
if self.code[i+opsize] == POP_TOP:
return [i+opsize]
if opcode == BUILD_LIST:
if (self.code[i+opsize] == DUP_TOP
and self.code[i+opsize+1] in (STORE_NAME, STORE_FAST)):
# del DUP/STORE_NAME x
toDel = [i+opsize, i+opsize+1]
nameDel = self.get_argument(i+opsize+1)
start = i+opsize+1
end = start
# del LOAD_NAME x
while end < len(self.code):
end = self.first_instr(end, len(self.code), (LOAD_NAME, LOAD_FAST))
if nameDel == self.get_argument(end):
toDel += [end]
break
if self.code[end] == LOAD_NAME:
end += self.op_size(LOAD_NAME)
else:
end += self.op_size(LOAD_FAST)
# log JA/POP_TOP to del and update PJIF
while start < end:
start = self.first_instr(start, end, (PJIF, PJIT)) # end = len(self.code)
if start is None: break
target = self.get_target(start)
if self.code[target] == POP_TOP and self.code[target-3] == JA:
toDel += [target, target-3]
# update PJIF
target = self.get_target(target-3)
self.restructJump(start, target)
start += self.op_size(PJIF)
# del DELETE_NAME x
start = end
while end < len(self.code):
end = self.first_instr(end, len(self.code), (DELETE_NAME, DELETE_FAST))
if nameDel == self.get_argument(end):
toDel += [end]
break
if self.code[end] == DELETE_NAME:
end += self.op_size(DELETE_NAME)
else:
end += self.op_size(DELETE_FAST)
return toDel
# change join(for..) struct
if opcode == SETUP_LOOP:
if self.code[i+3] == LOAD_FAST and self.code[i+6] == FOR_ITER:
end = self.first_instr(i, len(self.code), RETURN_VALUE)
end = self.first_instr(i, end, YIELD_VALUE)
if end and self.code[end+1] == POP_TOP and self.code[end+2] == JA and self.code[end+5] == POP_BLOCK:
return [i, end+5]
# with stmt
if opcode == WITH_CLEANUP:
chckDel = i-self.op_size(DELETE_NAME)
assert self.code[chckDel] in (DELETE_NAME, DELETE_FAST)
toDel = [chckDel]
nameDel = self.get_argument(chckDel)
chckDel -= self.op_size(LOAD_NAME)
assert self.code[chckDel] in (LOAD_NAME, LOAD_FAST)
toDel += [chckDel]
allStore = self.all_instr(0, i, (STORE_NAME, STORE_FAST))
chckStore = -1
for store in allStore:
if nameDel == self.get_argument(store):
if self.code[store+3] == LOAD_ATTR and self.code[store-3] == LOAD_ATTR \
and self.code[store-4] == DUP_TOP:
chckStore = store
assert chckStore > 0
toDel += [chckStore-4, chckStore-3, chckStore+3]
chckStp = -1
allSetup = self.all_instr(chckStore+3, i, (SETUP_FINALLY))
for stp in allSetup:
if chckDel == self.get_target(stp):
chckStp = stp
assert chckStp > 0
toDel += [chckStp]
chckDel = chckStore+3+self.op_size(self.code[chckStore+3])
while chckDel < chckStp-3:
toDel += [chckDel]
chckDel += self.op_size(self.code[chckDel])
if (self.code[chckStp-3] in (STORE_NAME, STORE_FAST)
and self.code[chckStp+3] in (LOAD_NAME, LOAD_FAST)
and self.code[chckStp+6] in (DELETE_NAME, DELETE_FAST)):
toDel += [chckStp-3, chckStp+3, chckStp+6]
# SETUP_WITH opcode dosen't exist in 2.5 but is necessary for the grammar
self.code[chckStore] = JUMP_ABSOLUTE # ugly hack
self.restructJump(chckStore, i)
self.toChange.append(chckStore)
return toDel
if opcode == NOP:
return [i]
return None
def getOpcodeToExp(self):
# we handle listExp, if opcode have to be resized
listExp = []
i=0
while i < len(self.code): # we can't use op_range for the moment
op = self.code[i]
if op in self.opc.hasArgumentExtended:
listExp += [i]
elif self.op_hasArgument(op):
i+=2
i+=1
return listExp
def restructCode(self, listDel, listExp):
'''
restruct linestarts and jump destination
'''
# restruct linestarts with deleted / modificated opcode
result = list()
for block in self.linestarts:
startBlock = 0
for toDel in listDel:
if toDel < block[0]:
startBlock -= self.op_size(self.code[toDel])
for toExp in listExp:
if toExp < block[0]:
startBlock += 2
result.append((block[0]+startBlock, block[1]))
self.linestarts = result
# handle opcodeToChange deplacement
for index in range(len(self.toChange)):
change = self.toChange[index]
delta = 0
for toDel in listDel:
if change > toDel:
delta -= self.op_size(self.code[toDel])
for toExp in listExp:
if change > toExp:
delta += 2
self.toChange[index] += delta
# restruct jmp opcode
if listDel:
for jmp in self.op_range(0, len(self.code)):
op = self.code[jmp]
if op in hasjrel+hasjabs:
offset = 0
jmpTarget = self.get_target(jmp)
for toDel in listDel:
if toDel < jmpTarget:
if op in hasjabs or jmp < toDel:
offset-=self.op_size(self.code[toDel])
self.restructJump(jmp, jmpTarget+offset)
if listExp:
jmp = 0
while jmp < len(self.code): # we can't use op_range for the moment
op = self.code[jmp]
if op in hasjrel+hasjabs:
offset = 0
jmpTarget = self.get_target(jmp)
for toExp in listExp:
if toExp < jmpTarget:
if op in hasjabs or jmp < toExp:
offset+=2
self.restructJump(jmp, jmpTarget+offset)
if self.op_hasArgument(op) and op not in self.opc.hasArgumentExtended:
jmp += 3
else: jmp += 1
def restructBytecode(self):
'''
add/change/delete bytecode for suiting bytecode 2.7
'''
# we can't use op_range for the moment
# convert jump opcode to 2.7
self.restructRelativeJump()
listExp = self.getOpcodeToExp()
# change code structure
if listExp:
listExp = sorted(list(set(listExp)))
self.restructCode([], listExp)
# we add arg to expended opcode
offset=0
for toExp in listExp:
self.code.insert(toExp+offset+1, 0)
self.code.insert(toExp+offset+1, 0)
offset+=2
# op_range is now ok :)
# add instruction to change in "toChange" list + MAJ toDel
listDel = []
for i in self.op_range(0, len(self.code)):
ret = self.getOpcodeToDel(i)
if ret is not None:
listDel += ret
# change code structure after deleting byte
if listDel:
listDel = sorted(list(set(listDel)))
self.restructCode(listDel, [])
# finaly we delete useless opcode
delta = 0
for x in listDel:
if self.op_hasArgument(self.code[x-delta]):
self.code.pop(x-delta)
self.code.pop(x-delta)
self.code.pop(x-delta)
delta += 3
else:
self.code.pop(x-delta)
delta += 1
def restructRelativeJump(self):
'''
change relative JUMP_IF_FALSE/TRUE to absolut jump
and remap the target of PJIF/PJIT
'''
i=0
while i < len(self.code): # we can't use op_range for the moment
op = self.code[i]
if(op in (PJIF, PJIT)):
target = self.get_argument(i)
target += i + 3
self.restructJump(i, target)
if self.op_hasArgument(op) and op not in self.opc.hasArgumentExtended:
i += 3
else: i += 1
i=0
while i < len(self.code): # we can't use op_range for the moment
op = self.code[i]
if(op in (PJIF, PJIT)):
target = self.get_target(i)
if self.code[target] == JA:
target = self.get_target(target)
self.restructJump(i, target)
if self.op_hasArgument(op) and op not in self.opc.hasArgumentExtended:
i += 3
else: i += 1
def restructJump(self, pos, newTarget):
if not (self.code[pos] in hasjabs+hasjrel):
raise 'Can t change this argument. Opcode is not a jump'
if newTarget > 0xFFFF:
raise NotImplementedError
offset = newTarget-self.get_target(pos)
target = self.get_argument(pos)+offset
if target < 0 or target > 0xFFFF:
raise NotImplementedError
self.code[pos+2] = (target >> 8) & 0xFF
self.code[pos+1] = target & 0xFF
def build_stmt_indices(self):
code = self.code
start = 0
end = len(code)
stmt_opcodes = {
SETUP_LOOP, BREAK_LOOP, CONTINUE_LOOP,
SETUP_FINALLY, END_FINALLY, SETUP_EXCEPT,
POP_BLOCK, STORE_FAST, DELETE_FAST, STORE_DEREF,
STORE_GLOBAL, DELETE_GLOBAL, STORE_NAME, DELETE_NAME,
STORE_ATTR, DELETE_ATTR, STORE_SUBSCR, DELETE_SUBSCR,
RETURN_VALUE, RAISE_VARARGS, POP_TOP,
PRINT_EXPR, PRINT_ITEM, PRINT_NEWLINE, PRINT_ITEM_TO, PRINT_NEWLINE_TO,
JUMP_ABSOLUTE, EXEC_STMT
}
stmt_opcode_seqs = [(PJIF, JF), (PJIF, JA), (PJIT, JF), (PJIT, JA)]
designator_ops = {
STORE_FAST, STORE_NAME, STORE_GLOBAL, STORE_DEREF, STORE_ATTR,
STORE_SLICE_0, STORE_SLICE_1, STORE_SLICE_2, STORE_SLICE_3,
STORE_SUBSCR, UNPACK_SEQUENCE, JA
}
prelim = self.all_instr(start, end, stmt_opcodes)
stmts = self.stmts = set(prelim)
pass_stmts = set()
for seq in stmt_opcode_seqs:
for i in self.op_range(start, end-(len(seq)+1)):
match = True
for elem in seq:
if elem != code[i]:
match = False
break
i += self.op_size(code[i])
if match:
i = self.prev[i]
stmts.add(i)
pass_stmts.add(i)
if pass_stmts:
stmt_list = list(stmts)
stmt_list.sort()
else:
stmt_list = prelim
last_stmt = -1
self.next_stmt = []
slist = self.next_stmt = []
i = 0
for s in stmt_list:
if code[s] == JA and s not in pass_stmts:
target = self.get_target(s)
if target > s or self.lines[last_stmt].l_no == self.lines[s].l_no:
stmts.remove(s)
continue
j = self.prev[s]
while code[j] == JA:
j = self.prev[j]
if code[j] == LIST_APPEND: # list comprehension
stmts.remove(s)
continue
elif code[s] == POP_TOP and code[self.prev[s]] == ROT_TWO:
stmts.remove(s)
continue
elif code[s] in designator_ops:
j = self.prev[s]
while code[j] in designator_ops:
j = self.prev[j]
if code[j] == FOR_ITER:
stmts.remove(s)
continue
last_stmt = s
slist += [s] * (s-i)
i = s
slist += [end] * (end-len(slist))
def next_except_jump(self, start):
'''
Return the next jump that was generated by an except SomeException:
construct in a try...except...else clause or None if not found.
'''
if self.code[start] == DUP_TOP:
except_match = self.first_instr(start, len(self.code), (PJIF))
if except_match:
jmp = self.prev[self.get_target(except_match)]
self.ignore_if.add(except_match)
self.not_continue.add(jmp)
return jmp
count_END_FINALLY = 0
count_SETUP_ = 0
for i in self.op_range(start, len(self.code)):
op = self.code[i]
if op == END_FINALLY:
if count_END_FINALLY == count_SETUP_:
if self.code[self.prev[i]] == NOP:
i = self.prev[i]
assert self.code[self.prev[i]] in (JA, JF, RETURN_VALUE)
self.not_continue.add(self.prev[i])
return self.prev[i]
count_END_FINALLY += 1
elif op in (SETUP_EXCEPT, SETUP_FINALLY):
count_SETUP_ += 1
# return self.lines[start].next
def detect_structure(self, pos, op=None):
'''
Detect type of block structures and their boundaries to fix optimizied jumps
in python2.3+
'''
code = self.code
# Ev remove this test and make op a mandatory argument -Dan
if op is None:
op = code[pos]
# Detect parent structure
parent = self.structs[0]
start = parent['start']
end = parent['end']
for s in self.structs:
_start = s['start']
_end = s['end']
if (_start <= pos < _end) and (_start >= start and _end <= end):
start = _start
end = _end
parent = s
# We need to know how many new structures were added in this run
if op == SETUP_LOOP:
start = pos+3
target = self.get_target(pos, op)
end = self.restrict_to_parent(target, parent)
if target != end:
self.fixed_jumps[pos] = end
(line_no, next_line_byte) = self.lines[pos]
jump_back = self.last_instr(start, end, JA,
next_line_byte, False)
if jump_back and jump_back != self.prev[end] and code[jump_back+3] in (JA, JF):
if code[self.prev[end]] == RETURN_VALUE or \
(code[self.prev[end]] == POP_BLOCK and code[self.prev[self.prev[end]]] == RETURN_VALUE):
jump_back = None
if not jump_back: # loop suite ends in return. wtf right?
jump_back = self.last_instr(start, end, RETURN_VALUE)
if not jump_back:
return
jump_back += 1
if code[self.prev[next_line_byte]] not in (PJIF, PJIT):
loop_type = 'for'
else:
loop_type = 'while'
self.ignore_if.add(self.prev[next_line_byte])
target = next_line_byte
end = jump_back + 3
else:
if self.get_target(jump_back) >= next_line_byte:
jump_back = self.last_instr(start, end, JA,
start, False)
if end > jump_back+4 and code[end] in (JF, JA):
if code[jump_back+4] in (JA, JF):
if self.get_target(jump_back+4) == self.get_target(end):
self.fixed_jumps[pos] = jump_back+4
end = jump_back+4
elif target < pos:
self.fixed_jumps[pos] = jump_back+4
end = jump_back+4
target = self.get_target(jump_back, JA)
if code[target] in (FOR_ITER, GET_ITER):
loop_type = 'for'
else:
loop_type = 'while'
test = self.prev[next_line_byte]
if test == pos:
loop_type = 'while 1'
elif self.code[test] in hasjabs+hasjrel:
self.ignore_if.add(test)
test_target = self.get_target(test)
if test_target > (jump_back+3):
jump_back = test_target
self.not_continue.add(jump_back)
self.loops.append(target)
self.structs.append({'type': loop_type + '-loop',
'start': target,
'end': jump_back})
if jump_back+3 != end:
self.structs.append({'type': loop_type + '-else',
'start': jump_back+3,
'end': end})
elif op == SETUP_EXCEPT:
start = pos+3
target = self.get_target(pos, op)
end = self.restrict_to_parent(target, parent)
if target != end:
self.fixed_jumps[pos] = end
# Add the try block
self.structs.append({'type': 'try',
'start': start,
'end': end-4})
# Now isolate the except and else blocks
end_else = start_else = self.get_target(self.prev[end])
# Add the except blocks
i = end
while i < len(self.code) and self.code[i] != END_FINALLY:
jmp = self.next_except_jump(i)
if jmp is None: # check
i = self.next_stmt[i]
continue
if self.code[jmp] == RETURN_VALUE:
self.structs.append({'type': 'except',
'start': i,
'end': jmp+1})
i = jmp + 1
else:
if self.get_target(jmp) != start_else:
end_else = self.get_target(jmp)
if self.code[jmp] == JF:
self.fixed_jumps[jmp] = -1
self.structs.append({'type': 'except',
'start': i,
'end': jmp})
i = jmp + 3
# Add the try-else block
if end_else != start_else:
r_end_else = self.restrict_to_parent(end_else, parent)
self.structs.append({'type': 'try-else',
'start': i+2, # check
'end': r_end_else})
self.fixed_jumps[i] = r_end_else
else:
self.fixed_jumps[i] = i+1
elif op in (PJIF, PJIT):
start = pos+3
target = self.get_target(pos, op)
rtarget = self.restrict_to_parent(target, parent)
pre = self.prev
if target != rtarget and parent['type'] == 'and/or':
self.fixed_jumps[pos] = rtarget
return
# does this jump to right after another cond jump?
# if so, it's part of a larger conditional
if (code[pre[target]] in (PJIF, PJIT)) and (target > pos):
self.fixed_jumps[pos] = pre[target]
self.structs.append({'type': 'and/or',
'start': start,
'end': pre[target]})
return
# is this an if and
if op == PJIF:
match = self.rem_or(start, self.next_stmt[pos], PJIF, target)
match = self.remove_mid_line_ifs(match)
if match:
if code[pre[rtarget]] in (JF, JA) \
and pre[rtarget] not in self.stmts \
and self.restrict_to_parent(self.get_target(pre[rtarget]), parent) == rtarget:
if code[pre[pre[rtarget]]] == JA \
and self.remove_mid_line_ifs([pos]) \
and target == self.get_target(pre[pre[rtarget]]) \
and (pre[pre[rtarget]] not in self.stmts or self.get_target(pre[pre[rtarget]]) > pre[pre[rtarget]])\
and 1 == len(self.remove_mid_line_ifs(self.rem_or(start, pre[pre[rtarget]], (PJIF, PJIT), target))):
pass
elif code[pre[pre[rtarget]]] == RETURN_VALUE \
and self.remove_mid_line_ifs([pos]) \
and 1 == (len(set(self.remove_mid_line_ifs(self.rem_or(start, pre[pre[rtarget]],
(PJIF, PJIT), target)))
| set(self.remove_mid_line_ifs(self.rem_or(start, pre[pre[rtarget]],
(PJIF, PJIT, JA), pre[rtarget], True))))):
pass
else:
fix = None
jump_ifs = self.all_instr(start, self.next_stmt[pos], PJIF)
last_jump_good = True
for j in jump_ifs:
if target == self.get_target(j):
if self.lines[j].next == j+3 and last_jump_good:
fix = j
break
else:
last_jump_good = False
self.fixed_jumps[pos] = fix or match[-1]
return
elif pos < rtarget and code[target] == ROT_TWO:
self.fixed_jumps[pos] = target
return
else:
self.fixed_jumps[pos] = match[-1]
return
else: # op == PJIT
if (pos+3) in self.load_asserts:
if code[pre[rtarget]] == RAISE_VARARGS:
return
self.load_asserts.remove(pos+3)
next = self.next_stmt[pos]
if pre[next] == pos:
pass
elif code[next] in (JF, JA) and target == self.get_target(next):
if code[pre[next]] == PJIF:
if code[next] == JF or target != rtarget or code[pre[pre[rtarget]]] not in (JA, RETURN_VALUE):
self.fixed_jumps[pos] = pre[next]
return
elif code[next] == JA and code[target] in (JA, JF) \
and self.get_target(target) == self.get_target(next):
self.fixed_jumps[pos] = pre[next]
return
# don't add a struct for a while test, it's already taken care of
if pos in self.ignore_if:
return
if code[pre[rtarget]] == JA and pre[rtarget] in self.stmts \
and pre[rtarget] != pos and pre[pre[rtarget]] != pos \
and not (code[rtarget] == JA and code[rtarget+3] == POP_BLOCK and code[pre[pre[rtarget]]] != JA):
rtarget = pre[rtarget]
# does the if jump just beyond a jump op, then this is probably an if statement
if code[pre[rtarget]] in (JA, JF):
if_end = self.get_target(pre[rtarget])
# is this a loop not an if?
if (if_end < pre[rtarget]) and (code[pre[if_end]] == SETUP_LOOP):
if(if_end > start):
return
end = self.restrict_to_parent(if_end, parent)
self.structs.append({'type': 'if-then',
'start': start,
'end': pre[rtarget]})
self.not_continue.add(pre[rtarget])
if rtarget < end:
self.structs.append({'type': 'if-else',
'start': rtarget,
'end': end})
elif code[pre[rtarget]] == RETURN_VALUE:
# if it's an old JUMP_IF_FALSE_OR_POP, JUMP_IF_TRUE_OR_POP (return 1<2<3 case)
if pos < rtarget and code[rtarget] == ROT_TWO:
return
self.structs.append({'type': 'if-then',
'start': start,
'end': rtarget})
self.return_end_ifs.add(pre[rtarget])
def find_jump_targets(self, code):
'''
Detect all offsets in a byte code which are jump targets.
Return the list of offsets.
This procedure is modelled after dis.findlables(), but here
for each target the number of jumps are counted.
'''
n = len(code)
self.structs = [{'type': 'root',
'start': 0,
'end': n-1}]
self.loops = [] # All loop entry points
self.fixed_jumps = {} # Map fixed jumps to their real destination
self.ignore_if = set()
self.build_stmt_indices()
self.not_continue = set()
self.return_end_ifs = set()
targets = {}
for i in self.op_range(0, n):
op = code[i]
# Determine structures and fix jumps for 2.3+
self.detect_structure(i, op)
if self.op_hasArgument(op):
label = self.fixed_jumps.get(i)
oparg = self.get_argument(i)
if label is None:
if op in hasjrel and op != FOR_ITER:
label = i + 3 + oparg
# elif op in hasjabs: Pas de gestion des jump abslt
# if op in (PJIF, PJIT): Or pop a faire
# if (oparg > i):
# label = oparg
if label is not None and label != -1:
targets[label] = targets.get(label, []) + [i]
elif op == END_FINALLY and i in self.fixed_jumps:
label = self.fixed_jumps[i]
targets[label] = targets.get(label, []) + [i]
return targets