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2.7 can have two JUMP_BACKs at the end of a while loop

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Fixes #215
This commit is contained in:
rocky
2019-01-27 21:41:17 -05:00
parent 47448e7ce4
commit bfceeac6c8
3 changed files with 35 additions and 0 deletions
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BIN
test/bytecode_2.7/05_while_elif.pyc Normal file
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16
test/simple_source/bug27+/05_while_elif.py Normal file
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@@ -0,0 +1,16 @@
# Bug in Python 2.7. Bug is bytecode for while loop having
# two consecutive JUMP_BACKS at the end of 'elif' and 'while'
# to the same place
def PreprocessConditionalStatement(self, IfList, ReplacedLine):
while self:
if self.__Token:
x = 1
elif not IfList:
if self <= 2:
continue
RegionSizeGuid = 3
if not RegionSizeGuid:
RegionLayoutLine = 5
continue
RegionLayoutLine = self.CurrentLineNumber
return 1

19
uncompyle6/parsers/parse27.py
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@@ -156,7 +156,13 @@ class Python27Parser(Python2Parser):
while1stmt ::= SETUP_LOOP returns bp_come_from
while1stmt ::= SETUP_LOOP l_stmts_opt JUMP_BACK POP_BLOCK COME_FROM
whilestmt ::= SETUP_LOOP testexpr l_stmts_opt JUMP_BACK POP_BLOCK _come_froms
# Should this be JUMP_BACK+ ?
# JUMP_BACK should all be to the same location
whilestmt ::= SETUP_LOOP testexpr l_stmts_opt JUMP_BACK JUMP_BACK POP_BLOCK _come_froms
while1elsestmt ::= SETUP_LOOP l_stmts JUMP_BACK POP_BLOCK
else_suitel COME_FROM
whileelsestmt ::= SETUP_LOOP testexpr l_stmts_opt JUMP_BACK POP_BLOCK
@@ -211,14 +217,17 @@ class Python27Parser(Python2Parser):
self.check_reduce['list_if_not'] = 'AST'
self.check_reduce['list_if'] = 'AST'
self.check_reduce['conditional_true'] = 'AST'
self.check_reduce['whilestmt'] = 'tokens'
return
def reduce_is_invalid(self, rule, ast, tokens, first, last):
invalid = super(Python27Parser,
self).reduce_is_invalid(rule, ast,
tokens, first, last)
if invalid:
return invalid
if rule == ('and', ('expr', 'jmp_false', 'expr', '\\e_come_from_opt')):
# Test that jmp_false jumps to the end of "and"
# or that it jumps to the same place as the end of "and"
@@ -249,6 +258,16 @@ class Python27Parser(Python2Parser):
jmp_target = jmp_true.offset + jmp_true.attr + 3
return not (jmp_target == tokens[last].offset or
tokens[last].pattr == jmp_true.pattr)
elif (rule[0] == 'whilestmt' and
rule[1][0:-2] ==
('SETUP_LOOP', 'testexpr', 'l_stmts_opt',
'JUMP_BACK', 'JUMP_BACK')):
# Make sure that the jump backs all go to the same place
i = last-1
while (tokens[i] != 'JUMP_BACK'):
i -= 1
return tokens[i].attr != tokens[i-1].attr
# elif rule[0] == ('conditional_true'):
# # FIXME: the below is a hack: we check expr for
# # nodes that could have possibly been a been a Boolean.