Jul 8, 2025 · Jun 19, 2025 · Jun 19, 2025 · Jul 7, 2025 · Jul 7, 2025 · Jul 7, 2025
diff --git a/mypyc/irbuild/context.py b/mypyc/irbuild/context.py
        # Holds the arg passed to send
        self.send_arg_reg: Value | None = None

        self.stop_iter_value_reg: Value | None = None

        # The switch block is used to decide which instruction to go using the value held in the
        # next-label register.
        self.switch_block = BasicBlock()
diff --git a/mypyc/irbuild/generator.py b/mypyc/irbuild/generator.py
    exc_tb = builder.add_local(Var("traceback"), object_rprimitive, is_arg=True)
    # TODO: Use the right type here instead of object?
    exc_arg = builder.add_local(Var("arg"), object_rprimitive, is_arg=True)
    stop_iter_value_arg = builder.add_local(Var("stop_iter_value"), object_pointer_rprimitive, is_arg=True)
    stop_iter_value_arg = builder.add_local(Var("stop_iter_ptr"), object_pointer_rprimitive, is_arg=True)
    # TODO: do something with stop_iter_value_arg

    cls.exc_regs = (exc_type, exc_val, exc_tb)
    cls.send_arg_reg = exc_arg
    cls.stop_iter_value_reg = stop_iter_value_arg

    cls.self_reg = builder.read(self_target, fitem.line)
    if builder.fn_info.can_merge_generator_and_env_classes():
diff --git a/mypyc/irbuild/nonlocalcontrol.py b/mypyc/irbuild/nonlocalcontrol.py
    Branch,
    Goto,
    Integer,
    LoadErrorValue,
    Register,
    Return,
    SetMem,
    Unreachable,
    Value,
 )
 from mypyc.ir.rtypes import object_rprimitive
 from mypyc.irbuild.targets import AssignmentTarget
 from mypyc.primitives.exc_ops import restore_exc_info_op, set_stop_iteration_value

        # StopIteration instead of using RaiseStandardError because
        # the obvious thing doesn't work if the value is a tuple
        # (???).

        true, false = BasicBlock(), BasicBlock()
        r = builder.fn_info.generator_class.stop_iter_value_reg

        builder.add(Branch(r, true, false, Branch.IS_ERROR))

        builder.activate_block(true)

        builder.call_c(set_stop_iteration_value, [value], NO_TRACEBACK_LINE_NO)
        builder.add(Unreachable())
        builder.builder.pop_error_handler()

        builder.activate_block(false)

        # Assign to provided pointer instead of raising an exception
        builder.add(SetMem(object_rprimitive, r, value))
        builder.add(Return(Integer(0, object_rprimitive)))

 class CleanupNonlocalControl(NonlocalControl):
    """Abstract nonlocal control that runs some cleanup code."""
diff --git a/mypyc/irbuild/statement.py b/mypyc/irbuild/statement.py

    if isinstance(iter_reg.type, RInstance) and iter_reg.type.class_ir.has_method(helper_method):
        # Second fast path optimization: call helper directly (see also comment above).
        fast_path = True
        obj = builder.read(iter_reg)
        nn = builder.none_object()
        m = MethodCall(obj, helper_method, [nn, nn, nn, nn, Integer(0, object_pointer_rprimitive)], line)
        stop_iter_val = Register(object_rprimitive)
        builder.assign(stop_iter_val, Integer(0, object_rprimitive), line)
        ptr = builder.add(LoadAddress(object_pointer_rprimitive, stop_iter_val))
        m = MethodCall(obj, helper_method, [nn, nn, nn, nn, ptr], line)
        # Generators have custom error handling, so disable normal error handling.
        m.error_kind = ERR_NEVER
        _y_init = builder.add(m)
    else:
        fast_path = False
        _y_init = builder.call_c(next_raw_op, [builder.read(iter_reg)], line)

    builder.add(Branch(_y_init, stop_block, main_block, Branch.IS_ERROR))

    # Try extracting a return value from a StopIteration and return it.
    # If it wasn't, this reraises the exception.
    builder.activate_block(stop_block)
    builder.assign(result, builder.call_c(check_stop_op, [], line), line)
    if fast_path:
        builder.assign(result, stop_iter_val, line)
    else:
        builder.assign(result, builder.call_c(check_stop_op, [], line), line)
    # Clear the spilled iterator/coroutine so that it will be freed.
    # Otherwise, the freeing of the spilled register would likely be delayed.
    err = builder.add(LoadErrorValue(iter_reg.type))
Original file line number	Diff line number	Diff line change
Expand Up		@@ -167,6 +167,8 @@ def __init__(self, ir: ClassIR) -> None:
		# Holds the arg passed to send
		self.send_arg_reg: Value \| None = None

		self.stop_iter_value_reg: Value \| None = None

		# The switch block is used to decide which instruction to go using the value held in the
		# next-label register.
		self.switch_block = BasicBlock()
Expand Down
Original file line number	Diff line number	Diff line change
Expand Up		@@ -376,11 +376,12 @@ def setup_env_for_generator_class(builder: IRBuilder) -> None:
		exc_tb = builder.add_local(Var("traceback"), object_rprimitive, is_arg=True)
		# TODO: Use the right type here instead of object?
		exc_arg = builder.add_local(Var("arg"), object_rprimitive, is_arg=True)
		stop_iter_value_arg = builder.add_local(Var("stop_iter_value"), object_pointer_rprimitive, is_arg=True)
		stop_iter_value_arg = builder.add_local(Var("stop_iter_ptr"), object_pointer_rprimitive, is_arg=True)
		# TODO: do something with stop_iter_value_arg

		cls.exc_regs = (exc_type, exc_val, exc_tb)
		cls.send_arg_reg = exc_arg
		cls.stop_iter_value_reg = stop_iter_value_arg

		cls.self_reg = builder.read(self_target, fitem.line)
		if builder.fn_info.can_merge_generator_and_env_classes():
Expand Down
Original file line number	Diff line number	Diff line change
Expand Up		@@ -14,11 +14,14 @@
		Branch,
		Goto,
		Integer,
		LoadErrorValue,
		Register,
		Return,
		SetMem,
		Unreachable,
		Value,
		)
		from mypyc.ir.rtypes import object_rprimitive
		from mypyc.irbuild.targets import AssignmentTarget
		from mypyc.primitives.exc_ops import restore_exc_info_op, set_stop_iteration_value

Expand DownExpand Up		@@ -108,10 +111,23 @@ def gen_return(self, builder: IRBuilder, value: Value, line: int) -> None:
		# StopIteration instead of using RaiseStandardError because
		# the obvious thing doesn't work if the value is a tuple
		# (???).

		true, false = BasicBlock(), BasicBlock()
		r = builder.fn_info.generator_class.stop_iter_value_reg

		builder.add(Branch(r, true, false, Branch.IS_ERROR))

		builder.activate_block(true)

		builder.call_c(set_stop_iteration_value, [value], NO_TRACEBACK_LINE_NO)
		builder.add(Unreachable())
		builder.builder.pop_error_handler()

		builder.activate_block(false)

		# Assign to provided pointer instead of raising an exception
		builder.add(SetMem(object_rprimitive, r, value))
		builder.add(Return(Integer(0, object_rprimitive)))

		class CleanupNonlocalControl(NonlocalControl):
		"""Abstract nonlocal control that runs some cleanup code."""
Expand Down
Original file line number	Diff line number	Diff line change
Expand Up		@@ -958,21 +958,29 @@ def emit_yield_from_or_await(

		if isinstance(iter_reg.type, RInstance) and iter_reg.type.class_ir.has_method(helper_method):
		# Second fast path optimization: call helper directly (see also comment above).
		fast_path = True
		obj = builder.read(iter_reg)
		nn = builder.none_object()
		m = MethodCall(obj, helper_method, [nn, nn, nn, nn, Integer(0, object_pointer_rprimitive)], line)
		stop_iter_val = Register(object_rprimitive)
		builder.assign(stop_iter_val, Integer(0, object_rprimitive), line)
		ptr = builder.add(LoadAddress(object_pointer_rprimitive, stop_iter_val))
		m = MethodCall(obj, helper_method, [nn, nn, nn, nn, ptr], line)
		# Generators have custom error handling, so disable normal error handling.
		m.error_kind = ERR_NEVER
		_y_init = builder.add(m)
		else:
		fast_path = False
		_y_init = builder.call_c(next_raw_op, [builder.read(iter_reg)], line)

		builder.add(Branch(_y_init, stop_block, main_block, Branch.IS_ERROR))

		# Try extracting a return value from a StopIteration and return it.
		# If it wasn't, this reraises the exception.
		builder.activate_block(stop_block)
		builder.assign(result, builder.call_c(check_stop_op, [], line), line)
		if fast_path:
		builder.assign(result, stop_iter_val, line)
		else:
		builder.assign(result, builder.call_c(check_stop_op, [], line), line)
		# Clear the spilled iterator/coroutine so that it will be freed.
		# Otherwise, the freeing of the spilled register would likely be delayed.
		err = builder.add(LoadErrorValue(iter_reg.type))
Expand Down