import dis
from itertools import combinations, product
import sys
import textwrap
import unittest
from test import support
from test.support.bytecode_helper import BytecodeTestCase, CfgOptimizationTestCase
def compile_pattern_with_fast_locals(pattern):
source = textwrap.dedent(
f"""
def f(x):
match x:
case {pattern}:
pass
"""
)
namespace = {}
exec(source, namespace)
return namespace["f"].__code__
def count_instr_recursively(f, opname):
count = 0
for instr in dis.get_instructions(f):
if instr.opname == opname:
count += 1
if hasattr(f, '__code__'):
f = f.__code__
for c in f.co_consts:
if hasattr(c, 'co_code'):
count += count_instr_recursively(c, opname)
return count
class TestTranforms(BytecodeTestCase):
def check_jump_targets(self, code):
instructions = list(dis.get_instructions(code))
targets = {instr.offset: instr for instr in instructions}
for instr in instructions:
if 'JUMP_' not in instr.opname:
continue
tgt = targets[instr.argval]
# jump to unconditional jump
if tgt.opname in ('JUMP_BACKWARD', 'JUMP_FORWARD'):
self.fail(f'{instr.opname} at {instr.offset} '
f'jumps to {tgt.opname} at {tgt.offset}')
# unconditional jump to RETURN_VALUE
if (instr.opname in ('JUMP_BACKWARD', 'JUMP_FORWARD') and
tgt.opname == 'RETURN_VALUE'):
self.fail(f'{instr.opname} at {instr.offset} '
f'jumps to {tgt.opname} at {tgt.offset}')
def check_lnotab(self, code):
"Check that the lnotab byte offsets are sensible."
code = dis._get_code_object(code)
lnotab = list(dis.findlinestarts(code))
# Don't bother checking if the line info is sensible, because
# most of the line info we can get at comes from lnotab.
min_bytecode = min(t[0] for t in lnotab)
max_bytecode = max(t[0] for t in lnotab)
self.assertGreaterEqual(min_bytecode, 0)
self.assertLess(max_bytecode, len(code.co_code))
# This could conceivably test more (and probably should, as there
# aren't very many tests of lnotab), if peepholer wasn't scheduled
# to be replaced anyway.
def test_unot(self):
# UNARY_NOT POP_JUMP_IF_FALSE --> POP_JUMP_IF_TRUE'
def unot(x):
if not x == 2:
del x
self.assertNotInBytecode(unot, 'UNARY_NOT')
self.assertNotInBytecode(unot, 'POP_JUMP_IF_FALSE')
self.assertInBytecode(unot, 'POP_JUMP_IF_TRUE')
self.check_lnotab(unot)
def test_elim_inversion_of_is_or_in(self):
for line, cmp_op, invert in (
('not a is b', 'IS_OP', 1,),
('not a is not b', 'IS_OP', 0,),
('not a in b', 'CONTAINS_OP', 1,),
('not a not in b', 'CONTAINS_OP', 0,),
):
with self.subTest(line=line):
code = compile(line, '', 'single')
self.assertInBytecode(code, cmp_op, invert)
self.check_lnotab(code)
def test_global_as_constant(self):
# LOAD_GLOBAL None/True/False --> LOAD_CONST None/True/False
def f():
x = None
x = None
return x
def g():
x = True
return x
def h():
x = False
return x
for func, elem in ((f, None), (g, True), (h, False)):
with self.subTest(func=func):
self.assertNotInBytecode(func, 'LOAD_GLOBAL')
self.assertInBytecode(func, 'LOAD_CONST', elem)
self.check_lnotab(func)
def f():
'Adding a docstring made this test fail in Py2.5.0'
return None
self.assertNotInBytecode(f, 'LOAD_GLOBAL')
self.assertInBytecode(f, 'LOAD_CONST', None)
self.check_lnotab(f)
def test_while_one(self):
# Skip over: LOAD_CONST trueconst POP_JUMP_IF_FALSE xx
def f():
while 1:
pass
return list
for elem in ('LOAD_CONST', 'POP_JUMP_IF_FALSE'):
self.assertNotInBytecode(f, elem)
for elem in ('JUMP_BACKWARD',):
self.assertInBytecode(f, elem)
self.check_lnotab(f)
def test_pack_unpack(self):
for line, elem in (
('a, = a,', 'LOAD_CONST',),
('a, b = a, b', 'SWAP',),
('a, b, c = a, b, c', 'SWAP',),
):
with self.subTest(line=line):
code = compile(line,'','single')
self.assertInBytecode(code, elem)
self.assertNotInBytecode(code, 'BUILD_TUPLE')
self.assertNotInBytecode(code, 'UNPACK_SEQUENCE')
self.check_lnotab(code)
def test_folding_of_tuples_of_constants(self):
for line, elem in (
('a = 1,2,3', (1, 2, 3)),
('("a","b","c")', ('a', 'b', 'c')),
('a,b,c = 1,2,3', (1, 2, 3)),
('(None, 1, None)', (None, 1, None)),
('((1, 2), 3, 4)', ((1, 2), 3, 4)),
):
with self.subTest(line=line):
code = compile(line,'','single')
self.assertInBytecode(code, 'LOAD_CONST', elem)
self.assertNotInBytecode(code, 'BUILD_TUPLE')
self.check_lnotab(code)
# Long tuples should be folded too.
code = compile(repr(tuple(range(10000))),'','single')
self.assertNotInBytecode(code, 'BUILD_TUPLE')
# One LOAD_CONST for the tuple, one for the None return value
load_consts = [instr for instr in dis.get_instructions(code)
if instr.opname == 'LOAD_CONST']
self.assertEqual(len(load_consts), 2)
self.check_lnotab(code)
# Bug 1053819: Tuple of constants misidentified when presented with:
# . . . opcode_with_arg 100 unary_opcode BUILD_TUPLE 1 . . .
# The following would segfault upon compilation
def crater():
(~[
0, 1, 2, 3, 4, 5, 6, 7, 8, 9,
0, 1, 2, 3, 4, 5, 6, 7, 8, 9,
0, 1, 2, 3, 4, 5, 6, 7, 8, 9,
0, 1, 2, 3, 4, 5, 6, 7, 8, 9,
0, 1, 2, 3, 4, 5, 6, 7, 8, 9,
0, 1, 2, 3, 4, 5, 6, 7, 8, 9,
0, 1, 2, 3, 4, 5, 6, 7, 8, 9,
0, 1, 2, 3, 4, 5, 6, 7, 8, 9,
0, 1, 2, 3, 4, 5, 6, 7, 8, 9,
0, 1, 2, 3, 4, 5, 6, 7, 8, 9,
],)
self.check_lnotab(crater)
def test_folding_of_lists_of_constants(self):
for line, elem in (
# in/not in constants with BUILD_LIST should be folded to a tuple:
('a in [1,2,3]', (1, 2, 3)),
('a not in ["a","b","c"]', ('a', 'b', 'c')),
('a in [None, 1, None]', (None, 1, None)),
('a not in [(1, 2), 3, 4]', ((1, 2), 3, 4)),
):
with self.subTest(line=line):
code = compile(line, '', 'single')
self.assertInBytecode(code, 'LOAD_CONST', elem)
self.assertNotInBytecode(code, 'BUILD_LIST')
self.check_lnotab(code)
def test_folding_of_sets_of_constants(self):
for line, elem in (
# in/not in constants with BUILD_SET should be folded to a frozenset:
('a in {1,2,3}', frozenset({1, 2, 3})),
('a not in {"a","b","c"}', frozenset({'a', 'c', 'b'})),
('a in {None, 1, None}', frozenset({1, None})),
('a not in {(1, 2), 3, 4}', frozenset({(1, 2), 3, 4})),
('a in {1, 2, 3, 3, 2, 1}', frozenset({1, 2, 3})),
):
with self.subTest(line=line):
code = compile(line, '', 'single')
self.assertNotInBytecode(code, 'BUILD_SET')
self.assertInBytecode(code, 'LOAD_CONST', elem)
self.check_lnotab(code)
# Ensure that the resulting code actually works:
def f(a):
return a in {1, 2, 3}
def g(a):
return a not in {1, 2, 3}
self.assertTrue(f(3))
self.assertTrue(not f(4))
self.check_lnotab(f)
self.assertTrue(not g(3))
self.assertTrue(g(4))
self.check_lnotab(g)
def test_folding_of_binops_on_constants(self):
for line, elem in (
('a = 2+3+4', 9), # chained fold
('"@"*4', '@@@@'), # check string ops
('a="abc" + "def"', 'abcdef'), # check string ops
('a = 3**4', 81), # binary power
('a = 3*4', 12), # binary multiply
('a = 13//4', 3), # binary floor divide
('a = 14%4', 2), # binary modulo
('a = 2+3', 5), # binary add
('a = 13-4', 9), # binary subtract
('a = (12,13)[1]', 13), # binary subscr
('a = 13 << 2', 52), # binary lshift
('a = 13 >> 2', 3), # binary rshift
('a = 13 & 7', 5), # binary and
('a = 13 ^ 7', 10), # binary xor
('a = 13 | 7', 15), # binary or
):
with self.subTest(line=line):
code = compile(line, '', 'single')
if isinstance(elem, int):
self.assertInBytecode(code, 'LOAD_SMALL_INT', elem)
else:
self.assertInBytecode(code, 'LOAD_CONST', elem)
for instr in dis.get_instructions(code):
self.assertFalse(instr.opname.startswith('BINARY_'))
self.check_lnotab(code)
# Verify that unfoldables are skipped
code = compile('a=2+"b"', '', 'single')
self.assertInBytecode(code, 'LOAD_SMALL_INT', 2)
self.assertInBytecode(code, 'LOAD_CONST', 'b')
self.check_lnotab(code)
# Verify that large sequences do not result from folding
code = compile('a="x"*10000', '', 'single')
self.assertInBytecode(code, 'LOAD_CONST', 10000)
self.assertNotIn("x"*10000, code.co_consts)
self.check_lnotab(code)
code = compile('a=1<<1000', '', 'single')
self.assertInBytecode(code, 'LOAD_CONST', 1000)
self.assertNotIn(1<<1000, code.co_consts)
self.check_lnotab(code)
code = compile('a=2**1000', '', 'single')
self.assertInBytecode(code, 'LOAD_CONST', 1000)
self.assertNotIn(2**1000, code.co_consts)
self.check_lnotab(code)
def test_binary_subscr_on_unicode(self):
# valid code get optimized
code = compile('"foo"[0]', '', 'single')
self.assertInBytecode(code, 'LOAD_CONST', 'f')
self.assertNotInBytecode(code, 'BINARY_SUBSCR')
self.check_lnotab(code)
code = compile('"\u0061\uffff"[1]', '', 'single')
self.assertInBytecode(code, 'LOAD_CONST', '\uffff')
self.assertNotInBytecode(code,'BINARY_SUBSCR')
self.check_lnotab(code)
# With PEP 393, non-BMP char get optimized
code = compile('"\U00012345"[0]', '', 'single')
self.assertInBytecode(code, 'LOAD_CONST', '\U00012345')
self.assertNotInBytecode(code, 'BINARY_SUBSCR')
self.check_lnotab(code)
# invalid code doesn't get optimized
# out of range
code = compile('"fuu"[10]', '', 'single')
self.assertInBytecode(code, 'BINARY_SUBSCR')
self.check_lnotab(code)
def test_folding_of_unaryops_on_constants(self):
for line, elem in (
('-0.5', -0.5), # unary negative
('-0.0', -0.0), # -0.0
('-(1.0-1.0)', -0.0), # -0.0 after folding
('-0', 0), # -0
('~-2', 1), # unary invert
('+1', 1), # unary positive
):
with self.subTest(line=line):
code = compile(line, '', 'single')
if isinstance(elem, int):
self.assertInBytecode(code, 'LOAD_SMALL_INT', elem)
else:
self.assertInBytecode(code, 'LOAD_CONST', elem)
for instr in dis.get_instructions(code):
self.assertFalse(instr.opname.startswith('UNARY_'))
self.check_lnotab(code)
# Check that -0.0 works after marshaling
def negzero():
return -(1.0-1.0)
for instr in dis.get_instructions(negzero):
self.assertFalse(instr.opname.startswith('UNARY_'))
self.check_lnotab(negzero)
# Verify that unfoldables are skipped
for line, elem, opname in (
('-"abc"', 'abc', 'UNARY_NEGATIVE'),
('~"abc"', 'abc', 'UNARY_INVERT'),
):
with self.subTest(line=line):
code = compile(line, '', 'single')
self.assertInBytecode(code, 'LOAD_CONST', elem)
self.assertInBytecode(code, opname)
self.check_lnotab(code)
def test_elim_extra_return(self):
# RETURN LOAD_CONST None RETURN --> RETURN
def f(x):
return x
self.assertNotInBytecode(f, 'LOAD_CONST', None)
returns = [instr for instr in dis.get_instructions(f)
if instr.opname == 'RETURN_VALUE']
self.assertEqual(len(returns), 1)
self.check_lnotab(f)
def test_elim_jump_to_return(self):
# JUMP_FORWARD to RETURN --> RETURN
def f(cond, true_value, false_value):
# Intentionally use two-line expression to test issue37213.
return (true_value if cond
else false_value)
self.check_jump_targets(f)
self.assertNotInBytecode(f, 'JUMP_FORWARD')
self.assertNotInBytecode(f, 'JUMP_BACKWARD')
returns = [instr for instr in dis.get_instructions(f)
if instr.opname == 'RETURN_VALUE']
self.assertEqual(len(returns), 2)
self.check_lnotab(f)
def test_elim_jump_to_uncond_jump(self):
# POP_JUMP_IF_FALSE to JUMP_FORWARD --> POP_JUMP_IF_FALSE to non-jump
def f():
if a:
# Intentionally use two-line expression to test issue37213.
if (c
or d):
foo()
else:
baz()
self.check_jump_targets(f)
self.check_lnotab(f)
def test_elim_jump_to_uncond_jump2(self):
# POP_JUMP_IF_FALSE to JUMP_BACKWARD --> POP_JUMP_IF_FALSE to non-jump
def f():
while a:
# Intentionally use two-line expression to test issue37213.
if (c
or d):
a = foo()
self.check_jump_targets(f)
self.check_lnotab(f)
def test_elim_jump_to_uncond_jump3(self):
# Intentionally use two-line expressions to test issue37213.
# POP_JUMP_IF_FALSE to POP_JUMP_IF_FALSE --> POP_JUMP_IF_FALSE to non-jump
def f(a, b, c):
return ((a and b)
and c)
self.check_jump_targets(f)
self.check_lnotab(f)
self.assertEqual(count_instr_recursively(f, 'POP_JUMP_IF_FALSE'), 2)
# POP_JUMP_IF_TRUE to POP_JUMP_IF_TRUE --> POP_JUMP_IF_TRUE to non-jump
def f(a, b, c):
return ((a or b)
or c)
self.check_jump_targets(f)
self.check_lnotab(f)
self.assertEqual(count_instr_recursively(f, 'POP_JUMP_IF_TRUE'), 2)
# JUMP_IF_FALSE_OR_POP to JUMP_IF_TRUE_OR_POP --> POP_JUMP_IF_FALSE to non-jump
def f(a, b, c):
return ((a and b)
or c)
self.check_jump_targets(f)
self.check_lnotab(f)
self.assertEqual(count_instr_recursively(f, 'POP_JUMP_IF_FALSE'), 1)
self.assertEqual(count_instr_recursively(f, 'POP_JUMP_IF_TRUE'), 1)
# POP_JUMP_IF_TRUE to POP_JUMP_IF_FALSE --> POP_JUMP_IF_TRUE to non-jump
def f(a, b, c):
return ((a or b)
and c)
self.check_jump_targets(f)
self.check_lnotab(f)
self.assertEqual(count_instr_recursively(f, 'POP_JUMP_IF_FALSE'), 1)
self.assertEqual(count_instr_recursively(f, 'POP_JUMP_IF_TRUE'), 1)
def test_elim_jump_to_uncond_jump4(self):
def f():
for i in range(5):
if i > 3:
print(i)
self.check_jump_targets(f)
def test_elim_jump_after_return1(self):
# Eliminate dead code: jumps immediately after returns can't be reached
def f(cond1, cond2):
if cond1: return 1
if cond2: return 2
while 1:
return 3
while 1:
if cond1: return 4
return 5
return 6
self.assertNotInBytecode(f, 'JUMP_FORWARD')
self.assertNotInBytecode(f, 'JUMP_BACKWARD')
returns = [instr for instr in dis.get_instructions(f)
if instr.opname == 'RETURN_VALUE']
self.assertLessEqual(len(returns), 6)
self.check_lnotab(f)
def test_make_function_doesnt_bail(self):
def f():
def g()->1+1:
pass
return g
self.assertNotInBytecode(f, 'BINARY_OP')
self.check_lnotab(f)
def test_constant_folding(self):
# Issue #11244: aggressive constant folding.
exprs = [
'3 * -5',
'-3 * 5',
'2 * (3 * 4)',
'(2 * 3) * 4',
'(-1, 2, 3)',
'(1, -2, 3)',
'(1, 2, -3)',
'(1, 2, -3) * 6',
'lambda x: x in {(3 * -5) + (-1 - 6), (1, -2, 3) * 2, None}',
]
for e in exprs:
with self.subTest(e=e):
code = compile(e, '', 'single')
for instr in dis.get_instructions(code):
self.assertFalse(instr.opname.startswith('UNARY_'))
self.assertFalse(instr.opname.startswith('BINARY_'))
self.assertFalse(instr.opname.startswith('BUILD_'))
self.check_lnotab(code)
def test_in_literal_list(self):
def containtest():
return x in [a, b]
self.assertEqual(count_instr_recursively(containtest, 'BUILD_LIST'), 0)
self.check_lnotab(containtest)
def test_iterate_literal_list(self):
def forloop():
for x in [a, b]:
pass
self.assertEqual(count_instr_recursively(forloop, 'BUILD_LIST'), 0)
self.check_lnotab(forloop)
def test_condition_with_binop_with_bools(self):
def f():
if True or False:
return 1
return 0
self.assertEqual(f(), 1)
self.check_lnotab(f)
def test_if_with_if_expression(self):
# Check bpo-37289
def f(x):
if (True if x else False):
return True
return False
self.assertTrue(f(True))
self.check_lnotab(f)
def test_trailing_nops(self):
# Check the lnotab of a function that even after trivial
# optimization has trailing nops, which the lnotab adjustment has to
# handle properly (bpo-38115).
def f(x):
while 1:
return 3
while 1:
return 5
return 6
self.check_lnotab(f)
def test_assignment_idiom_in_comprehensions(self):
def listcomp():
return [y for x in a for y in [f(x)]]
self.assertEqual(count_instr_recursively(listcomp, 'FOR_ITER'), 1)
def setcomp():
return {y for x in a for y in [f(x)]}
self.assertEqual(count_instr_recursively(setcomp, 'FOR_ITER'), 1)
def dictcomp():
return {y: y for x in a for y in [f(x)]}
self.assertEqual(count_instr_recursively(dictcomp, 'FOR_ITER'), 1)
def genexpr():
return (y for x in a for y in [f(x)])
self.assertEqual(count_instr_recursively(genexpr, 'FOR_ITER'), 1)
@support.requires_resource('cpu')
def test_format_combinations(self):
flags = '-+ #0'
testcases = [
*product(('', '1234', 'абвг'), 'sra'),
*product((1234, -1234), 'duioxX'),
*product((1234.5678901, -1234.5678901), 'duifegFEG'),
*product((float('inf'), -float('inf')), 'fegFEG'),
]
width_precs = [
*product(('', '1', '30'), ('', '.', '.0', '.2')),
('', '.40'),
('30', '.40'),
]
for value, suffix in testcases:
for width, prec in width_precs:
for r in range(len(flags) + 1):
for spec in combinations(flags, r):
fmt = '%' + ''.join(spec) + width + prec + suffix
with self.subTest(fmt=fmt, value=value):
s1 = fmt % value
s2 = eval(f'{fmt!r} % (x,)', {'x': value})
self.assertEqual(s2, s1, f'{fmt = }')
def test_format_misc(self):
def format(fmt, *values):
vars = [f'x{i+1}' for i in range(len(values))]
if len(vars) == 1:
args = '(' + vars[0] + ',)'
else:
args = '(' + ', '.join(vars) + ')'
return eval(f'{fmt!r} % {args}', dict(zip(vars, values)))
self.assertEqual(format('string'), 'string')
self.assertEqual(format('x = %s!', 1234), 'x = 1234!')
self.assertEqual(format('x = %d!', 1234), 'x = 1234!')
self.assertEqual(format('x = %x!', 1234), 'x = 4d2!')
self.assertEqual(format('x = %f!', 1234), 'x = 1234.000000!')
self.assertEqual(format('x = %s!', 1234.5678901), 'x = 1234.5678901!')
self.assertEqual(format('x = %f!', 1234.5678901), 'x = 1234.567890!')
self.assertEqual(format('x = %d!', 1234.5678901), 'x = 1234!')
self.assertEqual(format('x = %s%% %%%%', 1234), 'x = 1234% %%')
self.assertEqual(format('x = %s!', '%% %s'), 'x = %% %s!')
self.assertEqual(format('x = %s, y = %d', 12, 34), 'x = 12, y = 34')
def test_format_errors(self):
with self.assertRaisesRegex(TypeError,
'not enough arguments for format string'):
eval("'%s' % ()")
with self.assertRaisesRegex(TypeError,
'not all arguments converted during string formatting'):
eval("'%s' % (x, y)", {'x': 1, 'y': 2})
with self.assertRaisesRegex(ValueError, 'incomplete format'):
eval("'%s%' % (x,)", {'x': 1234})
with self.assertRaisesRegex(ValueError, 'incomplete format'):
eval("'%s%%%' % (x,)", {'x': 1234})
with self.assertRaisesRegex(TypeError,
'not enough arguments for format string'):
eval("'%s%z' % (x,)", {'x': 1234})
with self.assertRaisesRegex(ValueError, 'unsupported format character'):
eval("'%s%z' % (x, 5)", {'x': 1234})
with self.assertRaisesRegex(TypeError, 'a real number is required, not str'):
eval("'%d' % (x,)", {'x': '1234'})
with self.assertRaisesRegex(TypeError, 'an integer is required, not float'):
eval("'%x' % (x,)", {'x': 1234.56})
with self.assertRaisesRegex(TypeError, 'an integer is required, not str'):
eval("'%x' % (x,)", {'x': '1234'})
with self.assertRaisesRegex(TypeError, 'must be real number, not str'):
eval("'%f' % (x,)", {'x': '1234'})
with self.assertRaisesRegex(TypeError,
'not enough arguments for format string'):
eval("'%s, %s' % (x, *y)", {'x': 1, 'y': []})
with self.assertRaisesRegex(TypeError,
'not all arguments converted during string formatting'):
eval("'%s, %s' % (x, *y)", {'x': 1, 'y': [2, 3]})
def test_static_swaps_unpack_two(self):
def f(a, b):
a, b = a, b
b, a = a, b
self.assertNotInBytecode(f, "SWAP")
def test_static_swaps_unpack_three(self):
def f(a, b, c):
a, b, c = a, b, c
a, c, b = a, b, c
b, a, c = a, b, c
b, c, a = a, b, c
c, a, b = a, b, c
c, b, a = a, b, c
self.assertNotInBytecode(f, "SWAP")
def test_static_swaps_match_mapping(self):
for a, b, c in product("_a", "_b", "_c"):
pattern = f"{{'a': {a}, 'b': {b}, 'c': {c}}}"
with self.subTest(pattern):
code = compile_pattern_with_fast_locals(pattern)
self.assertNotInBytecode(code, "SWAP")
def test_static_swaps_match_class(self):
forms = [
"C({}, {}, {})",
"C({}, {}, c={})",
"C({}, b={}, c={})",
"C(a={}, b={}, c={})"
]
for a, b, c in product("_a", "_b", "_c"):
for form in forms:
pattern = form.format(a, b, c)
with self.subTest(pattern):
code = compile_pattern_with_fast_locals(pattern)
self.assertNotInBytecode(code, "SWAP")
def test_static_swaps_match_sequence(self):
swaps = {"*_, b, c", "a, *_, c", "a, b, *_"}
forms = ["{}, {}, {}", "{}, {}, *{}", "{}, *{}, {}", "*{}, {}, {}"]
for a, b, c in product("_a", "_b", "_c"):
for form in forms:
pattern = form.format(a, b, c)
with self.subTest(pattern):
code = compile_pattern_with_fast_locals(pattern)
if pattern in swaps:
# If this fails... great! Remove this pattern from swaps
# to prevent regressing on any improvement:
self.assertInBytecode(code, "SWAP")
else:
self.assertNotInBytecode(code, "SWAP")
class TestBuglets(unittest.TestCase):
def test_bug_11510(self):
# folded constant set optimization was commingled with the tuple
# unpacking optimization which would fail if the set had duplicate
# elements so that the set length was unexpected
def f():
x, y = {1, 1}
return x, y
with self.assertRaises(ValueError):
f()
def test_bpo_42057(self):
for i in range(10):
try:
raise Exception
except Exception or Exception:
pass
def test_bpo_45773_pop_jump_if_true(self):
compile("while True or spam: pass", "<test>", "exec")
def test_bpo_45773_pop_jump_if_false(self):
compile("while True or not spam: pass", "<test>", "exec")
class TestMarkingVariablesAsUnKnown(BytecodeTestCase):
def setUp(self):
self.addCleanup(sys.settrace, sys.gettrace())
sys.settrace(None)
def test_load_fast_known_simple(self):
def f():
x = 1
y = x + x
self.assertInBytecode(f, 'LOAD_FAST_LOAD_FAST')
def test_load_fast_unknown_simple(self):
def f():
if condition():
x = 1
print(x)
self.assertInBytecode(f, 'LOAD_FAST_CHECK')
self.assertNotInBytecode(f, 'LOAD_FAST')
def test_load_fast_unknown_because_del(self):
def f():
x = 1
del x
print(x)
self.assertInBytecode(f, 'LOAD_FAST_CHECK')
self.assertNotInBytecode(f, 'LOAD_FAST')
def test_load_fast_known_because_parameter(self):
def f1(x):
print(x)
self.assertInBytecode(f1, 'LOAD_FAST')
self.assertNotInBytecode(f1, 'LOAD_FAST_CHECK')
def f2(*, x):
print(x)
self.assertInBytecode(f2, 'LOAD_FAST')
self.assertNotInBytecode(f2, 'LOAD_FAST_CHECK')
def f3(*args):
print(args)
self.assertInBytecode(f3, 'LOAD_FAST')
self.assertNotInBytecode(f3, 'LOAD_FAST_CHECK')
def f4(**kwargs):
print(kwargs)
self.assertInBytecode(f4, 'LOAD_FAST')
self.assertNotInBytecode(f4, 'LOAD_FAST_CHECK')
def f5(x=0):
print(x)
self.assertInBytecode(f5, 'LOAD_FAST')
self.assertNotInBytecode(f5, 'LOAD_FAST_CHECK')
def test_load_fast_known_because_already_loaded(self):
def f():
if condition():
x = 1
print(x)
print(x)
self.assertInBytecode(f, 'LOAD_FAST_CHECK')
self.assertInBytecode(f, 'LOAD_FAST')
def test_load_fast_known_multiple_branches(self):
def f():
if condition():
x = 1
else:
x = 2
print(x)
self.assertInBytecode(f, 'LOAD_FAST')
self.assertNotInBytecode(f, 'LOAD_FAST_CHECK')
def test_load_fast_unknown_after_error(self):
def f():
try:
res = 1 / 0
except ZeroDivisionError:
pass
return res
# LOAD_FAST (known) still occurs in the no-exception branch.
# Assert that it doesn't occur in the LOAD_FAST_CHECK branch.
self.assertInBytecode(f, 'LOAD_FAST_CHECK')
def test_load_fast_unknown_after_error_2(self):
def f():
try:
1 / 0
except ZeroDivisionError:
print(a, b, c, d, e, f, g)
a = b = c = d = e = f = g = 1
self.assertInBytecode(f, 'LOAD_FAST_CHECK')
self.assertNotInBytecode(f, 'LOAD_FAST')
def test_load_fast_too_many_locals(self):
# When there get to be too many locals to analyze completely,
# later locals are all converted to LOAD_FAST_CHECK, except
# when a store or prior load occurred in the same basicblock.
def f():
a00 = a01 = a02 = a03 = a04 = a05 = a06 = a07 = a08 = a09 = 1
a10 = a11 = a12 = a13 = a14 = a15 = a16 = a17 = a18 = a19 = 1
a20 = a21 = a22 = a23 = a24 = a25 = a26 = a27 = a28 = a29 = 1
a30 = a31 = a32 = a33 = a34 = a35 = a36 = a37 = a38 = a39 = 1
a40 = a41 = a42 = a43 = a44 = a45 = a46 = a47 = a48 = a49 = 1
a50 = a51 = a52 = a53 = a54 = a55 = a56 = a57 = a58 = a59 = 1
a60 = a61 = a62 = a63 = a64 = a65 = a66 = a67 = a68 = a69 = 1
a70 = a71 = a72 = a73 = a74 = a75 = a76 = a77 = a78 = a79 = 1
del a72, a73
print(a73)
print(a70, a71, a72, a73)
while True:
print(a00, a01, a62, a63)
print(a64, a65, a78, a79)
self.assertInBytecode(f, 'LOAD_FAST_LOAD_FAST', ("a00", "a01"))
self.assertNotInBytecode(f, 'LOAD_FAST_CHECK', "a00")
self.assertNotInBytecode(f, 'LOAD_FAST_CHECK', "a01")
for i in 62, 63:
# First 64 locals: analyze completely
self.assertInBytecode(f, 'LOAD_FAST', f"a{i:02}")
self.assertNotInBytecode(f, 'LOAD_FAST_CHECK', f"a{i:02}")
for i in 64, 65, 78, 79:
# Locals >=64 not in the same basicblock
self.assertInBytecode(f, 'LOAD_FAST_CHECK', f"a{i:02}")
self.assertNotInBytecode(f, 'LOAD_FAST', f"a{i:02}")
for i in 70, 71:
# Locals >=64 in the same basicblock
self.assertInBytecode(f, 'LOAD_FAST', f"a{i:02}")
self.assertNotInBytecode(f, 'LOAD_FAST_CHECK', f"a{i:02}")
# del statements should invalidate within basicblocks.
self.assertInBytecode(f, 'LOAD_FAST_CHECK', "a72")
self.assertNotInBytecode(f, 'LOAD_FAST', "a72")
# previous checked loads within a basicblock enable unchecked loads
self.assertInBytecode(f, 'LOAD_FAST_CHECK', "a73")
self.assertInBytecode(f, 'LOAD_FAST', "a73")
def test_setting_lineno_no_undefined(self):
code = textwrap.dedent("""\
def f():
x = y = 2
if not x:
return 4
for i in range(55):
x + 6
L = 7
L = 8
L = 9
L = 10
""")
ns = {}
exec(code, ns)
f = ns['f']
self.assertInBytecode(f, "LOAD_FAST")
self.assertNotInBytecode(f, "LOAD_FAST_CHECK")
co_code = f.__code__.co_code
def trace(frame, event, arg):
if event == 'line' and frame.f_lineno == 9:
frame.f_lineno = 3
sys.settrace(None)
return None
return trace
sys.settrace(trace)
result = f()
self.assertIsNone(result)
self.assertInBytecode(f, "LOAD_FAST")
self.assertNotInBytecode(f, "LOAD_FAST_CHECK")
self.assertEqual(f.__code__.co_code, co_code)
def test_setting_lineno_one_undefined(self):
code = textwrap.dedent("""\
def f():
x = y = 2
if not x:
return 4
for i in range(55):
x + 6
del x
L = 8
L = 9
L = 10
""")
ns = {}
exec(code, ns)
f = ns['f']
self.assertInBytecode(f, "LOAD_FAST")
self.assertNotInBytecode(f, "LOAD_FAST_CHECK")
co_code = f.__code__.co_code
def trace(frame, event, arg):
if event == 'line' and frame.f_lineno == 9:
frame.f_lineno = 3
sys.settrace(None)
return None
return trace
e = r"assigning None to 1 unbound local"
with self.assertWarnsRegex(RuntimeWarning, e):
sys.settrace(trace)
result = f()
self.assertEqual(result, 4)
self.assertInBytecode(f, "LOAD_FAST")
self.assertNotInBytecode(f, "LOAD_FAST_CHECK")
self.assertEqual(f.__code__.co_code, co_code)
def test_setting_lineno_two_undefined(self):
code = textwrap.dedent("""\
def f():
x = y = 2
if not x:
return 4
for i in range(55):
x + 6
del x, y
L = 8
L = 9
L = 10
""")
ns = {}
exec(code, ns)
f = ns['f']
self.assertInBytecode(f, "LOAD_FAST")
self.assertNotInBytecode(f, "LOAD_FAST_CHECK")
co_code = f.__code__.co_code
def trace(frame, event, arg):
if event == 'line' and frame.f_lineno == 9:
frame.f_lineno = 3
sys.settrace(None)
return None
return trace
e = r"assigning None to 2 unbound locals"
with self.assertWarnsRegex(RuntimeWarning, e):
sys.settrace(trace)
result = f()
self.assertEqual(result, 4)
self.assertInBytecode(f, "LOAD_FAST")
self.assertNotInBytecode(f, "LOAD_FAST_CHECK")
self.assertEqual(f.__code__.co_code, co_code)
def make_function_with_no_checks(self):
code = textwrap.dedent("""\
def f():
x = 2
L = 3
L = 4
L = 5
if not L:
x + 7
y = 2
""")
ns = {}
exec(code, ns)
f = ns['f']
self.assertInBytecode(f, "LOAD_FAST")
self.assertNotInBytecode(f, "LOAD_FAST_CHECK")
return f
def test_modifying_local_does_not_add_check(self):
f = self.make_function_with_no_checks()
def trace(frame, event, arg):
if event == 'line' and frame.f_lineno == 4:
frame.f_locals["x"] = 42
sys.settrace(None)
return None
return trace
sys.settrace(trace)
f()
self.assertInBytecode(f, "LOAD_FAST")
self.assertNotInBytecode(f, "LOAD_FAST_CHECK")
def test_initializing_local_does_not_add_check(self):
f = self.make_function_with_no_checks()
def trace(frame, event, arg):
if event == 'line' and frame.f_lineno == 4:
frame.f_locals["y"] = 42
sys.settrace(None)
return None
return trace
sys.settrace(trace)
f()
self.assertInBytecode(f, "LOAD_FAST")
self.assertNotInBytecode(f, "LOAD_FAST_CHECK")
class DirectCfgOptimizerTests(CfgOptimizationTestCase):
def cfg_optimization_test(self, insts, expected_insts,
consts=None, expected_consts=None,
nlocals=0):
self.check_instructions(insts)
self.check_instructions(expected_insts)
if expected_consts is None:
expected_consts = consts
seq = self.seq_from_insts(insts)
opt_insts, opt_consts = self.get_optimized(seq, consts, nlocals)
expected_insts = self.seq_from_insts(expected_insts).get_instructions()
self.assertInstructionsMatch(opt_insts, expected_insts)
self.assertEqual(opt_consts, expected_consts)
def test_conditional_jump_forward_non_const_condition(self):
insts = [
('LOAD_NAME', 1, 11),
('POP_JUMP_IF_TRUE', lbl := self.Label(), 12),
('LOAD_CONST', 2, 13),
('RETURN_VALUE', None, 13),
lbl,
('LOAD_CONST', 3, 14),
('RETURN_VALUE', None, 14),
]
expected_insts = [
('LOAD_NAME', 1, 11),
('POP_JUMP_IF_TRUE', lbl := self.Label(), 12),
('LOAD_CONST', 1, 13),
('RETURN_VALUE', None, 13),
lbl,
('LOAD_CONST', 2, 14),
('RETURN_VALUE', None, 14),
]
self.cfg_optimization_test(insts,
expected_insts,
consts=[0, 1, 2, 3, 4],
expected_consts=[0, 2, 3])
def test_conditional_jump_forward_const_condition(self):
# The unreachable branch of the jump is removed, the jump
# becomes redundant and is replaced by a NOP (for the lineno)
insts = [
('LOAD_CONST', 3, 11),
('POP_JUMP_IF_TRUE', lbl := self.Label(), 12),
('LOAD_CONST', 2, 13),
lbl,
('LOAD_CONST', 3, 14),
('RETURN_VALUE', None, 14),
]
expected_insts = [
('NOP', None, 11),
('NOP', None, 12),
('LOAD_CONST', 1, 14),
('RETURN_VALUE', None, 14),
]
self.cfg_optimization_test(insts,
expected_insts,
consts=[0, 1, 2, 3, 4],
expected_consts=[0, 3])
def test_conditional_jump_backward_non_const_condition(self):
insts = [
lbl1 := self.Label(),
('LOAD_NAME', 1, 11),
('POP_JUMP_IF_TRUE', lbl1, 12),
('LOAD_NAME', 2, 13),
('RETURN_VALUE', None, 13),
]
expected = [
lbl := self.Label(),
('LOAD_NAME', 1, 11),
('POP_JUMP_IF_TRUE', lbl, 12),
('LOAD_NAME', 2, 13),
('RETURN_VALUE', None, 13),
]
self.cfg_optimization_test(insts, expected, consts=list(range(5)))
def test_conditional_jump_backward_const_condition(self):
# The unreachable branch of the jump is removed
insts = [
lbl1 := self.Label(),
('LOAD_CONST', 3, 11),
('POP_JUMP_IF_TRUE', lbl1, 12),
('LOAD_CONST', 2, 13),
('RETURN_VALUE', None, 13),
]
expected_insts = [
lbl := self.Label(),
('NOP', None, 11),
('JUMP', lbl, 12),
]
self.cfg_optimization_test(insts, expected_insts, consts=list(range(5)))
def test_except_handler_label(self):
insts = [
('SETUP_FINALLY', handler := self.Label(), 10),
('POP_BLOCK', None, -1),
('LOAD_CONST', 1, 11),
('RETURN_VALUE', None, 11),
handler,
('LOAD_CONST', 2, 12),
('RETURN_VALUE', None, 12),
]
expected_insts = [
('SETUP_FINALLY', handler := self.Label(), 10),
('LOAD_CONST', 1, 11),
('RETURN_VALUE', None, 11),
handler,
('LOAD_CONST', 2, 12),
('RETURN_VALUE', None, 12),
]
self.cfg_optimization_test(insts, expected_insts, consts=list(range(5)))
def test_no_unsafe_static_swap(self):
# We can't change order of two stores to the same location
insts = [
('LOAD_CONST', 0, 1),
('LOAD_CONST', 1, 2),
('LOAD_CONST', 2, 3),
('SWAP', 3, 4),
('STORE_FAST', 1, 4),
('STORE_FAST', 1, 4),
('POP_TOP', None, 4),
('LOAD_CONST', 0, 5),
('RETURN_VALUE', None, 5)
]
expected_insts = [
('LOAD_CONST', 0, 1),
('LOAD_CONST', 1, 2),
('NOP', None, 3),
('STORE_FAST', 1, 4),
('POP_TOP', None, 4),
('LOAD_CONST', 0, 5),
('RETURN_VALUE', None, 5)
]
self.cfg_optimization_test(insts, expected_insts, consts=list(range(3)), nlocals=1)
def test_dead_store_elimination_in_same_lineno(self):
insts = [
('LOAD_CONST', 0, 1),
('LOAD_CONST', 1, 2),
('LOAD_CONST', 2, 3),
('STORE_FAST', 1, 4),
('STORE_FAST', 1, 4),
('STORE_FAST', 1, 4),
('LOAD_CONST', 0, 5),
('RETURN_VALUE', None, 5)
]
expected_insts = [
('LOAD_CONST', 0, 1),
('LOAD_CONST', 1, 2),
('NOP', None, 3),
('POP_TOP', None, 4),
('STORE_FAST', 1, 4),
('LOAD_CONST', 0, 5),
('RETURN_VALUE', None, 5)
]
self.cfg_optimization_test(insts, expected_insts, consts=list(range(3)), nlocals=1)
def test_no_dead_store_elimination_in_different_lineno(self):
insts = [
('LOAD_CONST', 0, 1),
('LOAD_CONST', 1, 2),
('LOAD_CONST', 2, 3),
('STORE_FAST', 1, 4),
('STORE_FAST', 1, 5),
('STORE_FAST', 1, 6),
('LOAD_CONST', 0, 5),
('RETURN_VALUE', None, 5)
]
expected_insts = [
('LOAD_CONST', 0, 1),
('LOAD_CONST', 1, 2),
('LOAD_CONST', 2, 3),
('STORE_FAST', 1, 4),
('STORE_FAST', 1, 5),
('STORE_FAST', 1, 6),
('LOAD_CONST', 0, 5),
('RETURN_VALUE', None, 5)
]
self.cfg_optimization_test(insts, expected_insts, consts=list(range(3)), nlocals=1)
def test_unconditional_jump_threading(self):
def get_insts(lno1, lno2, op1, op2):
return [
lbl2 := self.Label(),
('LOAD_NAME', 0, 10),
(op1, lbl1 := self.Label(), lno1),
('LOAD_NAME', 1, 20),
lbl1,
(op2, lbl2, lno2),
]
for op1 in ('JUMP', 'JUMP_NO_INTERRUPT'):
for op2 in ('JUMP', 'JUMP_NO_INTERRUPT'):
# different lines
lno1, lno2 = (4, 5)
with self.subTest(lno = (lno1, lno2), ops = (op1, op2)):
insts = get_insts(lno1, lno2, op1, op2)
op = 'JUMP' if 'JUMP' in (op1, op2) else 'JUMP_NO_INTERRUPT'
expected_insts = [
('LOAD_NAME', 0, 10),
('NOP', None, 4),
(op, 0, 5),
]
self.cfg_optimization_test(insts, expected_insts, consts=list(range(5)))
# Threading
for lno1, lno2 in [(-1, -1), (-1, 5), (6, -1), (7, 7)]:
with self.subTest(lno = (lno1, lno2), ops = (op1, op2)):
insts = get_insts(lno1, lno2, op1, op2)
lno = lno1 if lno1 != -1 else lno2
if lno == -1:
lno = 10 # Propagated from the line before
op = 'JUMP' if 'JUMP' in (op1, op2) else 'JUMP_NO_INTERRUPT'
expected_insts = [
('LOAD_NAME', 0, 10),
(op, 0, lno),
]
self.cfg_optimization_test(insts, expected_insts, consts=list(range(5)))
if __name__ == "__main__":
unittest.main()
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