def translate_safe_generator_call(builder: IRBuilder, expr: CallExpr,
callee: RefExpr) -> Optional[Value]:
# Special cases for things that consume iterators where we know we
# can safely compile a generator into a list.
if (len(expr.args) > 0 and expr.arg_kinds[0] == ARG_POS
and isinstance(expr.args[0], GeneratorExpr)):
if isinstance(callee, MemberExpr):
return builder.gen_method_call(
builder.accept(callee.expr), callee.name,
([translate_list_comprehension(builder, expr.args[0])] +
[builder.accept(arg) for arg in expr.args[1:]]),
builder.node_type(expr), expr.line, expr.arg_kinds,
expr.arg_names)
else:
if len(expr.args) == 1 and callee.fullname == "builtins.tuple":
val = sequence_from_generator_preallocate_helper(
builder,
expr.args[0],
empty_op_llbuilder=builder.builder.new_tuple_with_length,
set_item_op=new_tuple_set_item_op)
if val is not None:
return val
return builder.call_refexpr_with_args(
expr, callee,
([translate_list_comprehension(builder, expr.args[0])] +
[builder.accept(arg) for arg in expr.args[1:]]))
return None
def translate_tuple_from_generator_call(
builder: IRBuilder, expr: CallExpr, callee: RefExpr) -> Optional[Value]:
# Special case for simplest tuple creation from a generator, for example
# tuple(f(x) for x in other_list/other_tuple)
# translate_safe_generator_call() would take care of other cases if this fails.
if (len(expr.args) == 1
and expr.arg_kinds[0] == ARG_POS
and isinstance(expr.args[0], GeneratorExpr)):
return sequence_from_generator_preallocate_helper(
builder, expr.args[0],
empty_op_llbuilder=builder.builder.new_tuple_with_length,
set_item_op=new_tuple_set_item_op)
return None
def translate_list_from_generator_call(
builder: IRBuilder, expr: CallExpr, callee: RefExpr) -> Optional[Value]:
"""Special case for simplest list comprehension.
For example:
list(f(x) for x in some_list/some_tuple/some_str)
'translate_list_comprehension()' would take care of other cases
if this fails.
"""
if (len(expr.args) == 1
and expr.arg_kinds[0] == ARG_POS
and isinstance(expr.args[0], GeneratorExpr)):
return sequence_from_generator_preallocate_helper(
builder, expr.args[0],
empty_op_llbuilder=builder.builder.new_list_op_with_length,
set_item_op=new_list_set_item_op)
return None
def dict_methods_fast_path(builder: IRBuilder, expr: CallExpr,
callee: RefExpr) -> Optional[Value]:
# Specialize a common case when list() is called on a dictionary view
# method call, for example foo = list(bar.keys()).
if not (len(expr.args) == 1 and expr.arg_kinds == [ARG_POS]):
return None
arg = expr.args[0]
# Special case for simplest list comprehension, for example
# list(x for x in tmp_list)
# TODO: The following code should be moved to a new function after
# supporting multiple specialize functions
if not isinstance(callee, MemberExpr) and isinstance(arg, GeneratorExpr):
val = sequence_from_generator_preallocate_helper(
builder,
arg,
empty_op_llbuilder=builder.builder.new_list_op_with_length,
set_item_op=new_list_set_item_op)
if val is not None:
return val
if not (isinstance(arg, CallExpr) and not arg.args
and isinstance(arg.callee, MemberExpr)):
return None
base = arg.callee.expr
attr = arg.callee.name
rtype = builder.node_type(base)
if not (is_dict_rprimitive(rtype) and attr in ('keys', 'values', 'items')):
return None
obj = builder.accept(base)
# Note that it is not safe to use fast methods on dict subclasses, so
# the corresponding helpers in CPy.h fallback to (inlined) generic logic.
if attr == 'keys':
return builder.call_c(dict_keys_op, [obj], expr.line)
elif attr == 'values':
return builder.call_c(dict_values_op, [obj], expr.line)
else:
return builder.call_c(dict_items_op, [obj], expr.line)
