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", "", "exec") def test_bpo_45773_pop_jump_if_false(self): compile("while True or not spam: pass", "", "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()