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Bugs caused by 3.x jump_forward misclasification

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rocky
2016-07-10 07:53:15 -04:00
parent 52b71bb01a
commit 3cd3f7ccdf
2 changed files with 48 additions and 19 deletions
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8
uncompyle6/parsers/parse3.py
View File

@@ -295,6 +295,14 @@ class Python3Parser(PythonParser):
binary_subscr2 ::= expr expr DUP_TOP_TWO BINARY_SUBSCR
'''
def p_misc3(self, args):
'''
for_block ::= l_stmts
iflaststmtl ::= testexpr c_stmts_opt
iflaststmt ::= testexpr c_stmts_opt34
c_stmts_opt34 ::= JUMP_BACK JUMP_ABSOLUTE c_stmts_opt
'''
@staticmethod
def call_fn_name(token):
"""Customize CALL_FUNCTION to add the number of positional arguments"""

59
uncompyle6/scanners/scanner3.py
View File

@@ -44,7 +44,10 @@ class Scanner3(scan.Scanner):
def __init__(self, version, show_asm=None):
super(Scanner3, self).__init__(version, show_asm)
# Above initializes self.opc
# Create opcode classification sets
# Note: super initilization above initializes self.opc
# Opcodes that can start a statement.
self.statement_opcodes = frozenset([
self.opc.SETUP_LOOP, self.opc.BREAK_LOOP, self.opc.CONTINUE_LOOP,
self.opc.SETUP_FINALLY, self.opc.END_FINALLY, self.opc.SETUP_EXCEPT,
@@ -62,12 +65,8 @@ class Scanner3(scan.Scanner):
self.opc.PRINT_EXPR, self.opc.JUMP_ABSOLUTE
])
self.statement_opcode_sequences = [
(self.opc.POP_JUMP_IF_FALSE, self.opc.JUMP_FORWARD),
(self.opc.POP_JUMP_IF_FALSE, self.opc.JUMP_ABSOLUTE),
(self.opc.POP_JUMP_IF_TRUE, self.opc.JUMP_FORWARD),
(self.opc.POP_JUMP_IF_TRUE, self.opc.JUMP_ABSOLUTE)]
# Opcodes that can start a designator non-terminal.
# FIXME: JUMP_ABSOLUTE is weird. What's up with that?
self.designator_ops = frozenset([
self.opc.STORE_FAST, self.opc.STORE_NAME, self.opc.STORE_GLOBAL,
self.opc.STORE_DEREF, self.opc.STORE_ATTR,
@@ -75,9 +74,6 @@ class Scanner3(scan.Scanner):
self.opc.JUMP_ABSOLUTE, self.opc.UNPACK_EX
])
self.jump_forward = frozenset([self.opc.JUMP_ABSOLUTE,
self.opc.JUMP_FORWARD])
self.jump_if_pop = frozenset([self.opc.JUMP_IF_FALSE_OR_POP,
self.opc.JUMP_IF_TRUE_OR_POP])
@@ -86,6 +82,8 @@ class Scanner3(scan.Scanner):
self.opc.POP_JUMP_IF_TRUE,
self.opc.POP_JUMP_IF_FALSE])
# Opcodes that take a variable number of arguments
# (expr's)
self.varargs = frozenset([self.opc.BUILD_LIST,
self.opc.BUILD_TUPLE,
self.opc.BUILD_SET,
@@ -94,6 +92,14 @@ class Scanner3(scan.Scanner):
self.opc.UNPACK_SEQUENCE,
self.opc.RAISE_VARARGS])
# Not really a set, but still clasification-like
self.statement_opcode_sequences = [
(self.opc.POP_JUMP_IF_FALSE, self.opc.JUMP_FORWARD),
(self.opc.POP_JUMP_IF_FALSE, self.opc.JUMP_ABSOLUTE),
(self.opc.POP_JUMP_IF_TRUE, self.opc.JUMP_FORWARD),
(self.opc.POP_JUMP_IF_TRUE, self.opc.JUMP_ABSOLUTE)]
def disassemble(self, co, classname=None, code_objects={}, show_asm=None):
"""
Disassemble a Python 3 code object, returning a list of 'Token'.
@@ -494,7 +500,7 @@ class Scanner3(scan.Scanner):
jump_back = self.last_instr(start, end, self.opc.JUMP_ABSOLUTE,
next_line_byte, False)
if jump_back and jump_back != self.prev_op[end] and code[jump_back+3] in self.jump_forward:
if jump_back and jump_back != self.prev_op[end] and self.is_jump_forward(jump_back+3):
if (code[self.prev_op[end]] == self.opc.RETURN_VALUE
or (code[self.prev_op[end]] == self.opc.POP_BLOCK
and code[self.prev_op[self.prev_op[end]]] == self.opc.RETURN_VALUE)):
@@ -513,8 +519,8 @@ class Scanner3(scan.Scanner):
else:
if self.get_target(jump_back) >= next_line_byte:
jump_back = self.last_instr(start, end, self.opc.JUMP_ABSOLUTE, start, False)
if end > jump_back+4 and code[end] in self.jump_forward:
if code[jump_back+4] in self.jump_forward:
if end > jump_back+4 and self.is_jump_forward(end):
if self.is_jump_forward(jump_back+4):
if self.get_target(jump_back+4) == self.get_target(end):
self.fixed_jumps[offset] = jump_back+4
end = jump_back+4
@@ -569,7 +575,7 @@ class Scanner3(scan.Scanner):
# Is it an "and" inside an "if" block
if op == self.opc.POP_JUMP_IF_FALSE:
# Search for other POP_JUMP_IF_FALSE targetting the same op,
# Search for another POP_JUMP_IF_FALSE targetting the same op,
# in current statement, starting from current offset, and filter
# everything inside inner 'or' jumps and midline ifs
match = self.rem_or(start, self.next_stmt[offset],
@@ -578,7 +584,8 @@ class Scanner3(scan.Scanner):
# If we still have any offsets in set, start working on it
if match:
if (code[prev_op[rtarget]] in self.jump_forward and prev_op[rtarget] not in self.stmts and
is_jump_forward = self.is_jump_forward(prev_op[rtarget])
if (is_jump_forward and prev_op[rtarget] not in self.stmts and
self.restrict_to_parent(self.get_target(prev_op[rtarget]), parent) == rtarget):
if (code[prev_op[prev_op[rtarget]]] == self.opc.JUMP_ABSOLUTE
and self.remove_mid_line_ifs([offset]) and
@@ -612,14 +619,15 @@ class Scanner3(scan.Scanner):
self.fixed_jumps[offset] = fix or match[-1]
return
else:
self.fixed_jumps[offset] = match[-1]
if is_jump_forward:
self.fixed_jumps[offset] = match[-1]
return
# op == POP_JUMP_IF_TRUE
else:
next = self.next_stmt[offset]
if prev_op[next] == offset:
pass
elif code[next] in self.jump_forward and target == self.get_target(next):
elif self.is_jump_forward(next) and target == self.get_target(next):
if code[prev_op[next]] == self.opc.POP_JUMP_IF_FALSE:
if (code[next] == self.opc.JUMP_FORWARD
or target != rtarget
@@ -627,7 +635,7 @@ class Scanner3(scan.Scanner):
(self.opc.JUMP_ABSOLUTE, self.opc.RETURN_VALUE)):
self.fixed_jumps[offset] = prev_op[next]
return
elif (code[next] == self.opc.JUMP_ABSOLUTE and code[target] in self.jump_forward and
elif (code[next] == self.opc.JUMP_ABSOLUTE and self.is_jump_forward(target) and
self.get_target(target) == self.get_target(next)):
self.fixed_jumps[offset] = prev_op[next]
return
@@ -646,7 +654,7 @@ class Scanner3(scan.Scanner):
rtarget = prev_op[rtarget]
# Does the "if" jump just beyond a jump op, then this is probably an if statement
if code[prev_op[rtarget]] in self.jump_forward:
if self.is_jump_forward(prev_op[rtarget]):
if_end = self.get_target(prev_op[rtarget])
# Is this a loop and not an "if" statement?
@@ -681,6 +689,19 @@ class Scanner3(scan.Scanner):
else:
self.fixed_jumps[offset] = self.restrict_to_parent(target, parent)
def is_jump_forward(self, offset):
"""
Return True if the code at offset is some sort of jump forward.
That is, it is ether "JUMP_FORWARD" or an absolute jump that
goes forward.
"""
if self.code[offset] == self.opc.JUMP_FORWARD:
return True
if self.code[offset] != self.opc.JUMP_ABSOLUTE:
return False
return offset < self.get_target(offset)
def next_except_jump(self, start):
"""
Return the next jump that was generated by an except SomeException: