Construct GeneratorUsage

Performance Diagrams

Source Code with Construct

def calledRepeatedly():
    # We measure making a generator iterator step or not.
    def generator():
        yield 1
        yield 2
        yield 3

    gen = generator()

    x = next(gen)
# construct_begin
    next(gen)
# construct_end

    return x

for x in xrange(50000):
    calledRepeatedly()

print("OK.")

Source Code without Construct

def calledRepeatedly():
    # We measure making a generator iterator step or not.
    def generator():
        yield 1
        yield 2
        yield 3

    gen = generator()

    x = next(gen)
# construct_begin



    return x

for x in xrange(50000):
    calledRepeatedly()

print("OK.")

Context Diff of Source Code

	Construct			Baseline
	29			29
	30	gen = generator()		30	gen = generator()
	31			31
	32	x = next(gen)		32	x = next(gen)
	33	# construct_begin		33	# construct_begin
t	34	next(gen)	t	34
	35	# construct_end		35
	36			36
	37	return x		37	return x
	38			38
	39	for x in xrange(50000):		39	for x in xrange(50000):
	40	calledRepeatedly()		40	calledRepeatedly()

Context Diff of Generated Code

	Construct			Baseline
	142	PyObject *tmp_assign_source_1;		142	PyObject *tmp_assign_source_1;
	143	PyObject *tmp_assign_source_2;		143	PyObject *tmp_assign_source_2;
	144	PyObject *tmp_assign_source_3;		144	PyObject *tmp_assign_source_3;
	145	PyObject *tmp_called_name_1;		145	PyObject *tmp_called_name_1;
	146	PyObject *tmp_return_value;		146	PyObject *tmp_return_value;
n	147	NUITKA_MAY_BE_UNUSED PyObject *tmp_unused;	n
	148	PyObject *tmp_value_name_1;		147	PyObject *tmp_value_name_1;
n	149	PyObject *tmp_value_name_2;	n
	150	static struct Nuitka_FrameObject *cache_frame_f612342abc679987e34962a48d5d8ef9 = NULL;		148	static struct Nuitka_FrameObject *cache_frame_f612342abc679987e34962a48d5d8ef9 = NULL;
	151			149
	152	struct Nuitka_FrameObject *frame_f612342abc679987e34962a48d5d8ef9;		150	struct Nuitka_FrameObject *frame_f612342abc679987e34962a48d5d8ef9;
	153			151
	154	char const *type_description;		152	char const *type_description;
	213	goto frame_exception_exit_1;		211	goto frame_exception_exit_1;
	214	}		212	}
	215	assert( var_x == NULL );		213	assert( var_x == NULL );
	216	var_x = tmp_assign_source_3;		214	var_x = tmp_assign_source_3;
	217			215
n	218	tmp_value_name_2 = var_gen;	n
	219
	220	if ( tmp_value_name_2 == NULL )
	221	{
	222
	223	exception_type = PyExc_UnboundLocalError;
	224	Py_INCREF( exception_type );
	225	exception_value = PyUnicode_FromFormat( "local variable '%s' referenced before assignment", "gen" );
	226	exception_tb = NULL;
	227	NORMALIZE_EXCEPTION( &exception_type, &exception_value, &exception_tb );
	228	CHAIN_EXCEPTION( exception_value );
	229
	230	exception_lineno = 34;
	231	type_description = "ooo";
	232	goto frame_exception_exit_1;
	233	}
	234
	235	tmp_unused = ITERATOR_NEXT( tmp_value_name_2 );
	236	if ( tmp_unused == NULL )
	237	{
	238	if ( !ERROR_OCCURRED() )
	239	{
	240	exception_type = PyExc_StopIteration;
	241	Py_INCREF( exception_type );
	242	exception_value = NULL;
	243	exception_tb = NULL;
	244	}
	245	else
	246	{
	247	FETCH_ERROR_OCCURRED( &exception_type, &exception_value, &exception_tb );
	248	}
	249
	250
	251	type_description = "ooo";
	252	exception_lineno = 34;
	253	goto frame_exception_exit_1;
	254	}
	255	Py_DECREF( tmp_unused );
	256			216
	257	#if 0		217	#if 0
	258	RESTORE_FRAME_EXCEPTION( frame_f612342abc679987e34962a48d5d8ef9 );		218	RESTORE_FRAME_EXCEPTION( frame_f612342abc679987e34962a48d5d8ef9 );
	259	#endif		219	#endif
	260			220
	298			258
	299	frame_no_exception_1:;		259	frame_no_exception_1:;
	300			260
	301	tmp_return_value = var_x;		261	tmp_return_value = var_x;
	302			262
n	303	if ( tmp_return_value == NULL )	n	263	CHECK_OBJECT( tmp_return_value );
	304	{
	305
	306	exception_type = PyExc_UnboundLocalError;
	307	Py_INCREF( exception_type );
	308	exception_value = PyUnicode_FromFormat( "local variable '%s' referenced before assignment", "x" );
	309	exception_tb = NULL;
	310	NORMALIZE_EXCEPTION( &exception_type, &exception_value, &exception_tb );
	311	CHAIN_EXCEPTION( exception_value );
	312
	313
	314
	315	goto try_except_handler_1;
	316	}
	317
	318	Py_INCREF( tmp_return_value );		264	Py_INCREF( tmp_return_value );
	319	goto try_return_handler_1;		265	goto try_return_handler_1;
	320	// tried codes exits in all cases		266	// tried codes exits in all cases
	321	NUITKA_CANNOT_GET_HERE( __main__$$$function_1_calledRepeatedly );		267	NUITKA_CANNOT_GET_HERE( __main__$$$function_1_calledRepeatedly );
	322	return NULL;		268	return NULL;
	346	Py_XDECREF( var_generator );		292	Py_XDECREF( var_generator );
	347	var_generator = NULL;		293	var_generator = NULL;
	348			294
	349	Py_XDECREF( var_gen );		295	Py_XDECREF( var_gen );
	350	var_gen = NULL;		296	var_gen = NULL;
t	351		t
	352	Py_XDECREF( var_x );
	353	var_x = NULL;
	354			297
	355	// Re-raise.		298	// Re-raise.
	356	exception_type = exception_keeper_type_1;		299	exception_type = exception_keeper_type_1;
	357	exception_value = exception_keeper_value_1;		300	exception_value = exception_keeper_value_1;
	358	exception_tb = exception_keeper_tb_1;		301	exception_tb = exception_keeper_tb_1;