def transform_raise_stmt(builder: IRBuilder, s: RaiseStmt) -> None:
if s.expr is None:
builder.primitive_op(reraise_exception_op, [], NO_TRACEBACK_LINE_NO)
builder.add(Unreachable())
return
exc = builder.accept(s.expr)
builder.primitive_op(raise_exception_op, [exc], s.line)
builder.add(Unreachable())
def transform_block(builder: IRBuilder, block: Block) -> None:
if not block.is_unreachable:
for stmt in block.body:
builder.accept(stmt)
# Raise a RuntimeError if we hit a non-empty unreachable block.
# Don't complain about empty unreachable blocks, since mypy inserts
# those after `if MYPY`.
elif block.body:
builder.add(RaiseStandardError(RaiseStandardError.RUNTIME_ERROR,
'Reached allegedly unreachable code!',
block.line))
builder.add(Unreachable())
def translate_next_call(builder: IRBuilder, expr: CallExpr,
callee: RefExpr) -> Optional[Value]:
# Special case for calling next() on a generator expression, an
# idiom that shows up some in mypy.
#
# For example, next(x for x in l if x.id == 12, None) will
# generate code that searches l for an element where x.id == 12
# and produce the first such object, or None if no such element
# exists.
if not (expr.arg_kinds in ([ARG_POS], [ARG_POS, ARG_POS])
and isinstance(expr.args[0], GeneratorExpr)):
return None
gen = expr.args[0]
retval = builder.alloc_temp(builder.node_type(expr))
default_val = None
if len(expr.args) > 1:
default_val = builder.accept(expr.args[1])
exit_block = BasicBlock()
def gen_inner_stmts() -> None:
# next takes the first element of the generator, so if
# something gets produced, we are done.
builder.assign(retval, builder.accept(gen.left_expr),
gen.left_expr.line)
builder.goto(exit_block)
loop_params = list(zip(gen.indices, gen.sequences, gen.condlists))
builder.comprehension_helper(loop_params, gen_inner_stmts, gen.line)
# Now we need the case for when nothing got hit. If there was
# a default value, we produce it, and otherwise we raise
# StopIteration.
if default_val:
builder.assign(retval, default_val, gen.left_expr.line)
builder.goto(exit_block)
else:
builder.add(
RaiseStandardError(RaiseStandardError.STOP_ITERATION, None,
expr.line))
builder.add(Unreachable())
builder.activate_block(exit_block)
return retval
def transform_index_expr(builder: IRBuilder, expr: IndexExpr) -> Value:
base = builder.accept(expr.base)
if isinstance(base.type, RTuple) and isinstance(expr.index, IntExpr):
return builder.add(TupleGet(base, expr.index.value, expr.line))
index_reg = builder.accept(expr.index)
return builder.gen_method_call(base, '__getitem__', [index_reg],
builder.node_type(expr), expr.line)
def transform_del_item(builder: IRBuilder, target: AssignmentTarget, line: int) -> None:
if isinstance(target, AssignmentTargetIndex):
builder.gen_method_call(
target.base,
'__delitem__',
[target.index],
result_type=None,
line=line
)
elif isinstance(target, AssignmentTargetAttr):
key = builder.load_static_unicode(target.attr)
builder.add(PrimitiveOp([target.obj, key], py_delattr_op, line))
elif isinstance(target, AssignmentTargetRegister):
# Delete a local by assigning an error value to it, which will
# prompt the insertion of uninit checks.
builder.add(Assign(target.register,
builder.add(LoadErrorValue(target.type, undefines=True))))
elif isinstance(target, AssignmentTargetTuple):
for subtarget in target.items:
transform_del_item(builder, subtarget, line)
def translate_len(builder: IRBuilder, expr: CallExpr,
callee: RefExpr) -> Optional[Value]:
# Special case builtins.len
if (len(expr.args) == 1 and expr.arg_kinds == [ARG_POS]):
expr_rtype = builder.node_type(expr.args[0])
if isinstance(expr_rtype, RTuple):
# len() of fixed-length tuple can be trivially determined statically,
# though we still need to evaluate it.
builder.accept(expr.args[0])
return builder.add(LoadInt(len(expr_rtype.types)))
return None
def transform_conditional_expr(builder: IRBuilder,
expr: ConditionalExpr) -> Value:
if_body, else_body, next = BasicBlock(), BasicBlock(), BasicBlock()
builder.process_conditional(expr.cond, if_body, else_body)
expr_type = builder.node_type(expr)
# Having actual Phi nodes would be really nice here!
target = builder.alloc_temp(expr_type)
builder.activate_block(if_body)
true_value = builder.accept(expr.if_expr)
true_value = builder.coerce(true_value, expr_type, expr.line)
builder.add(Assign(target, true_value))
builder.goto(next)
builder.activate_block(else_body)
false_value = builder.accept(expr.else_expr)
false_value = builder.coerce(false_value, expr_type, expr.line)
builder.add(Assign(target, false_value))
builder.goto(next)
builder.activate_block(next)
return target
def dataclass_non_ext_info(builder: IRBuilder, cdef: ClassDef) -> Optional[NonExtClassInfo]:
"""Set up a NonExtClassInfo to track dataclass attributes.
In addition to setting up a normal extension class for dataclasses,
we also collect its class attributes like a non-extension class so
that we can hand them to the dataclass decorator.
"""
if is_dataclass(cdef):
return NonExtClassInfo(
builder.primitive_op(new_dict_op, [], cdef.line),
builder.add(TupleSet([], cdef.line)),
builder.primitive_op(new_dict_op, [], cdef.line),
builder.primitive_op(type_object_op, [], cdef.line),
)
else:
return None
def transform_tuple_expr(builder: IRBuilder, expr: TupleExpr) -> Value:
if any(isinstance(item, StarExpr) for item in expr.items):
# create a tuple of unknown length
return _visit_tuple_display(builder, expr)
# create a tuple of fixed length (RTuple)
tuple_type = builder.node_type(expr)
# When handling NamedTuple et. al we might not have proper type info,
# so make some up if we need it.
types = (tuple_type.types if isinstance(tuple_type, RTuple) else
[object_rprimitive] * len(expr.items))
items = []
for item_expr, item_type in zip(expr.items, types):
reg = builder.accept(item_expr)
items.append(builder.coerce(reg, item_type, item_expr.line))
return builder.add(TupleSet(items, expr.line))
def transform_name_expr(builder: IRBuilder, expr: NameExpr) -> Value:
assert expr.node, "RefExpr not resolved"
fullname = expr.node.fullname
if fullname in name_ref_ops:
# Use special access op for this particular name.
desc = name_ref_ops[fullname]
assert desc.result_type is not None
return builder.add(PrimitiveOp([], desc, expr.line))
if isinstance(expr.node, Var) and expr.node.is_final:
value = builder.emit_load_final(
expr.node,
fullname,
expr.name,
builder.is_native_ref_expr(expr),
builder.types[expr],
expr.line,
)
if value is not None:
return value
if isinstance(expr.node,
MypyFile) and expr.node.fullname in builder.imports:
return builder.load_module(expr.node.fullname)
# If the expression is locally defined, then read the result from the corresponding
# assignment target and return it. Otherwise if the expression is a global, load it from
# the globals dictionary.
# Except for imports, that currently always happens in the global namespace.
if expr.kind == LDEF and not (isinstance(expr.node, Var)
and expr.node.is_suppressed_import):
# Try to detect and error when we hit the irritating mypy bug
# where a local variable is cast to None. (#5423)
if (isinstance(expr.node, Var)
and is_none_rprimitive(builder.node_type(expr))
and expr.node.is_inferred):
builder.error(
"Local variable '{}' has inferred type None; add an annotation"
.format(expr.node.name), expr.node.line)
# TODO: Behavior currently only defined for Var and FuncDef node types.
return builder.read(builder.get_assignment_target(expr), expr.line)
return builder.load_global(expr)
def try_finally_resolve_control(builder: IRBuilder,
cleanup_block: BasicBlock,
finally_control: FinallyNonlocalControl,
old_exc: Value,
ret_reg: Optional[Value]) -> BasicBlock:
"""Resolve the control flow out of a finally block.
This means returning if there was a return, propagating
exceptions, break/continue (soon), or just continuing on.
"""
reraise, rest = BasicBlock(), BasicBlock()
builder.add(Branch(old_exc, rest, reraise, Branch.IS_ERROR))
# Reraise the exception if there was one
builder.activate_block(reraise)
builder.primitive_op(reraise_exception_op, [], NO_TRACEBACK_LINE_NO)
builder.add(Unreachable())
builder.builder.pop_error_handler()
# If there was a return, keep returning
if ret_reg:
builder.activate_block(rest)
return_block, rest = BasicBlock(), BasicBlock()
builder.add(Branch(ret_reg, rest, return_block, Branch.IS_ERROR))
builder.activate_block(return_block)
builder.nonlocal_control[-1].gen_return(builder, ret_reg, -1)
# TODO: handle break/continue
builder.activate_block(rest)
out_block = BasicBlock()
builder.goto(out_block)
# If there was an exception, restore again
builder.activate_block(cleanup_block)
finally_control.gen_cleanup(builder, -1)
builder.primitive_op(keep_propagating_op, [], NO_TRACEBACK_LINE_NO)
builder.add(Unreachable())
return out_block
def gen_glue_ne_method(builder: IRBuilder, cls: ClassIR, line: int) -> FuncIR:
"""Generate a __ne__ method from a __eq__ method. """
builder.enter()
rt_args = (RuntimeArg("self", RInstance(cls)), RuntimeArg("rhs", object_rprimitive))
# The environment operates on Vars, so we make some up
fake_vars = [(Var(arg.name), arg.type) for arg in rt_args]
args = [
builder.read(
builder.environment.add_local_reg(
var, type, is_arg=True
),
line
)
for var, type in fake_vars
] # type: List[Value]
builder.ret_types[-1] = object_rprimitive
# If __eq__ returns NotImplemented, then __ne__ should also
not_implemented_block, regular_block = BasicBlock(), BasicBlock()
eqval = builder.add(MethodCall(args[0], '__eq__', [args[1]], line))
not_implemented = builder.primitive_op(not_implemented_op, [], line)
builder.add(Branch(
builder.binary_op(eqval, not_implemented, 'is', line),
not_implemented_block,
regular_block,
Branch.BOOL_EXPR))
builder.activate_block(regular_block)
retval = builder.coerce(
builder.unary_op(eqval, 'not', line), object_rprimitive, line
)
builder.add(Return(retval))
builder.activate_block(not_implemented_block)
builder.add(Return(not_implemented))
blocks, env, ret_type, _ = builder.leave()
return FuncIR(
FuncDecl('__ne__', cls.name, builder.module_name,
FuncSignature(rt_args, ret_type)),
blocks, env)
def allocate_class(builder: IRBuilder, cdef: ClassDef) -> Value:
# OK AND NOW THE FUN PART
base_exprs = cdef.base_type_exprs + cdef.removed_base_type_exprs
if base_exprs:
bases = [builder.accept(x) for x in base_exprs]
tp_bases = builder.primitive_op(new_tuple_op, bases, cdef.line)
else:
tp_bases = builder.add(LoadErrorValue(object_rprimitive, is_borrowed=True))
modname = builder.load_static_unicode(builder.module_name)
template = builder.add(LoadStatic(object_rprimitive, cdef.name + "_template",
builder.module_name, NAMESPACE_TYPE))
# Create the class
tp = builder.primitive_op(pytype_from_template_op,
[template, tp_bases, modname], cdef.line)
# Immediately fix up the trait vtables, before doing anything with the class.
ir = builder.mapper.type_to_ir[cdef.info]
if not ir.is_trait and not ir.builtin_base:
builder.add(Call(
FuncDecl(cdef.name + '_trait_vtable_setup',
None, builder.module_name,
FuncSignature([], bool_rprimitive)), [], -1))
# Populate a '__mypyc_attrs__' field containing the list of attrs
builder.primitive_op(py_setattr_op, [
tp, builder.load_static_unicode('__mypyc_attrs__'),
create_mypyc_attrs_tuple(builder, builder.mapper.type_to_ir[cdef.info], cdef.line)],
cdef.line)
# Save the class
builder.add(InitStatic(tp, cdef.name, builder.module_name, NAMESPACE_TYPE))
# Add it to the dict
builder.primitive_op(dict_set_item_op,
[
builder.load_globals_dict(),
builder.load_static_unicode(cdef.name),
tp,
], cdef.line)
return tp
def transform_assert_stmt(builder: IRBuilder, a: AssertStmt) -> None:
if builder.options.strip_asserts:
return
cond = builder.accept(a.expr)
ok_block, error_block = BasicBlock(), BasicBlock()
builder.add_bool_branch(cond, ok_block, error_block)
builder.activate_block(error_block)
if a.msg is None:
# Special case (for simpler generated code)
builder.add(RaiseStandardError(RaiseStandardError.ASSERTION_ERROR, None, a.line))
elif isinstance(a.msg, StrExpr):
# Another special case
builder.add(RaiseStandardError(RaiseStandardError.ASSERTION_ERROR, a.msg.value,
a.line))
else:
# The general case -- explicitly construct an exception instance
message = builder.accept(a.msg)
exc_type = builder.load_module_attr_by_fullname('builtins.AssertionError', a.line)
exc = builder.py_call(exc_type, [message], a.line)
builder.primitive_op(raise_exception_op, [exc], a.line)
builder.add(Unreachable())
builder.activate_block(ok_block)
def transform_try_except(builder: IRBuilder,
body: GenFunc,
handlers: Sequence[
Tuple[Optional[Expression], Optional[Expression], GenFunc]],
else_body: Optional[GenFunc],
line: int) -> None:
"""Generalized try/except/else handling that takes functions to gen the bodies.
The point of this is to also be able to support with."""
assert handlers, "try needs except"
except_entry, exit_block, cleanup_block = BasicBlock(), BasicBlock(), BasicBlock()
double_except_block = BasicBlock()
# If there is an else block, jump there after the try, otherwise just leave
else_block = BasicBlock() if else_body else exit_block
# Compile the try block with an error handler
builder.builder.push_error_handler(except_entry)
builder.goto_and_activate(BasicBlock())
body()
builder.goto(else_block)
builder.builder.pop_error_handler()
# The error handler catches the error and then checks it
# against the except clauses. We compile the error handler
# itself with an error handler so that it can properly restore
# the *old* exc_info if an exception occurs.
# The exception chaining will be done automatically when the
# exception is raised, based on the exception in exc_info.
builder.builder.push_error_handler(double_except_block)
builder.activate_block(except_entry)
old_exc = builder.maybe_spill(builder.primitive_op(error_catch_op, [], line))
# Compile the except blocks with the nonlocal control flow overridden to clear exc_info
builder.nonlocal_control.append(
ExceptNonlocalControl(builder.nonlocal_control[-1], old_exc))
# Process the bodies
for type, var, handler_body in handlers:
next_block = None
if type:
next_block, body_block = BasicBlock(), BasicBlock()
matches = builder.primitive_op(
exc_matches_op, [builder.accept(type)], type.line
)
builder.add(Branch(matches, body_block, next_block, Branch.BOOL_EXPR))
builder.activate_block(body_block)
if var:
target = builder.get_assignment_target(var)
builder.assign(
target,
builder.primitive_op(get_exc_value_op, [], var.line),
var.line
)
handler_body()
builder.goto(cleanup_block)
if next_block:
builder.activate_block(next_block)
# Reraise the exception if needed
if next_block:
builder.primitive_op(reraise_exception_op, [], NO_TRACEBACK_LINE_NO)
builder.add(Unreachable())
builder.nonlocal_control.pop()
builder.builder.pop_error_handler()
# Cleanup for if we leave except through normal control flow:
# restore the saved exc_info information and continue propagating
# the exception if it exists.
builder.activate_block(cleanup_block)
builder.primitive_op(restore_exc_info_op, [builder.read(old_exc)], line)
builder.goto(exit_block)
# Cleanup for if we leave except through a raised exception:
# restore the saved exc_info information and continue propagating
# the exception.
builder.activate_block(double_except_block)
builder.primitive_op(restore_exc_info_op, [builder.read(old_exc)], line)
builder.primitive_op(keep_propagating_op, [], NO_TRACEBACK_LINE_NO)
builder.add(Unreachable())
# If present, compile the else body in the obvious way
if else_body:
builder.activate_block(else_block)
else_body()
builder.goto(exit_block)
builder.activate_block(exit_block)
def generate_attr_defaults(builder: IRBuilder, cdef: ClassDef) -> None:
"""Generate an initialization method for default attr values (from class vars)"""
cls = builder.mapper.type_to_ir[cdef.info]
if cls.builtin_base:
return
# Pull out all assignments in classes in the mro so we can initialize them
# TODO: Support nested statements
default_assignments = []
for info in reversed(cdef.info.mro):
if info not in builder.mapper.type_to_ir:
continue
for stmt in info.defn.defs.body:
if (isinstance(stmt, AssignmentStmt)
and isinstance(stmt.lvalues[0], NameExpr)
and not is_class_var(stmt.lvalues[0])
and not isinstance(stmt.rvalue, TempNode)):
if stmt.lvalues[0].name == '__slots__':
continue
# Skip type annotated assignments in dataclasses
if is_dataclass(cdef) and stmt.type:
continue
default_assignments.append(stmt)
if not default_assignments:
return
builder.enter()
builder.ret_types[-1] = bool_rprimitive
rt_args = (RuntimeArg(SELF_NAME, RInstance(cls)),)
self_var = builder.read(add_self_to_env(builder.environment, cls), -1)
for stmt in default_assignments:
lvalue = stmt.lvalues[0]
assert isinstance(lvalue, NameExpr)
if not stmt.is_final_def and not is_constant(stmt.rvalue):
builder.warning('Unsupported default attribute value', stmt.rvalue.line)
# If the attribute is initialized to None and type isn't optional,
# don't initialize it to anything.
attr_type = cls.attr_type(lvalue.name)
if isinstance(stmt.rvalue, RefExpr) and stmt.rvalue.fullname == 'builtins.None':
if (not is_optional_type(attr_type) and not is_object_rprimitive(attr_type)
and not is_none_rprimitive(attr_type)):
continue
val = builder.coerce(builder.accept(stmt.rvalue), attr_type, stmt.line)
builder.add(SetAttr(self_var, lvalue.name, val, -1))
builder.add(Return(builder.primitive_op(true_op, [], -1)))
blocks, env, ret_type, _ = builder.leave()
ir = FuncIR(
FuncDecl('__mypyc_defaults_setup',
cls.name, builder.module_name,
FuncSignature(rt_args, ret_type)),
blocks, env)
builder.functions.append(ir)
cls.methods[ir.name] = ir
def transform_class_def(builder: IRBuilder, cdef: ClassDef) -> None:
ir = builder.mapper.type_to_ir[cdef.info]
# We do this check here because the base field of parent
# classes aren't necessarily populated yet at
# prepare_class_def time.
if any(ir.base_mro[i].base != ir. base_mro[i + 1] for i in range(len(ir.base_mro) - 1)):
builder.error("Non-trait MRO must be linear", cdef.line)
if ir.allow_interpreted_subclasses:
for parent in ir.mro:
if not parent.allow_interpreted_subclasses:
builder.error(
'Base class "{}" does not allow interpreted subclasses'.format(
parent.fullname), cdef.line)
# Currently, we only create non-extension classes for classes that are
# decorated or inherit from Enum. Classes decorated with @trait do not
# apply here, and are handled in a different way.
if ir.is_ext_class:
# If the class is not decorated, generate an extension class for it.
type_obj = allocate_class(builder, cdef) # type: Optional[Value]
non_ext = None # type: Optional[NonExtClassInfo]
dataclass_non_ext = dataclass_non_ext_info(builder, cdef)
else:
non_ext_bases = populate_non_ext_bases(builder, cdef)
non_ext_metaclass = find_non_ext_metaclass(builder, cdef, non_ext_bases)
non_ext_dict = setup_non_ext_dict(builder, cdef, non_ext_metaclass, non_ext_bases)
# We populate __annotations__ for non-extension classes
# because dataclasses uses it to determine which attributes to compute on.
# TODO: Maybe generate more precise types for annotations
non_ext_anns = builder.primitive_op(new_dict_op, [], cdef.line)
non_ext = NonExtClassInfo(non_ext_dict, non_ext_bases, non_ext_anns, non_ext_metaclass)
dataclass_non_ext = None
type_obj = None
attrs_to_cache = [] # type: List[Lvalue]
for stmt in cdef.defs.body:
if isinstance(stmt, OverloadedFuncDef) and stmt.is_property:
if not ir.is_ext_class:
# properties with both getters and setters in non_extension
# classes not supported
builder.error("Property setters not supported in non-extension classes",
stmt.line)
for item in stmt.items:
with builder.catch_errors(stmt.line):
transform_method(builder, cdef, non_ext, get_func_def(item))
elif isinstance(stmt, (FuncDef, Decorator, OverloadedFuncDef)):
# Ignore plugin generated methods (since they have no
# bodies to compile and will need to have the bodies
# provided by some other mechanism.)
if cdef.info.names[stmt.name].plugin_generated:
continue
with builder.catch_errors(stmt.line):
transform_method(builder, cdef, non_ext, get_func_def(stmt))
elif isinstance(stmt, PassStmt):
continue
elif isinstance(stmt, AssignmentStmt):
if len(stmt.lvalues) != 1:
builder.error("Multiple assignment in class bodies not supported", stmt.line)
continue
lvalue = stmt.lvalues[0]
if not isinstance(lvalue, NameExpr):
builder.error("Only assignment to variables is supported in class bodies",
stmt.line)
continue
# We want to collect class variables in a dictionary for both real
# non-extension classes and fake dataclass ones.
var_non_ext = non_ext or dataclass_non_ext
if var_non_ext:
add_non_ext_class_attr(builder, var_non_ext, lvalue, stmt, cdef, attrs_to_cache)
if non_ext:
continue
# Variable declaration with no body
if isinstance(stmt.rvalue, TempNode):
continue
# Only treat marked class variables as class variables.
if not (is_class_var(lvalue) or stmt.is_final_def):
continue
typ = builder.load_native_type_object(cdef.fullname)
value = builder.accept(stmt.rvalue)
builder.primitive_op(
py_setattr_op, [typ, builder.load_static_unicode(lvalue.name), value], stmt.line)
if builder.non_function_scope() and stmt.is_final_def:
builder.init_final_static(lvalue, value, cdef.name)
elif isinstance(stmt, ExpressionStmt) and isinstance(stmt.expr, StrExpr):
# Docstring. Ignore
pass
else:
builder.error("Unsupported statement in class body", stmt.line)
if not non_ext: # That is, an extension class
generate_attr_defaults(builder, cdef)
create_ne_from_eq(builder, cdef)
if dataclass_non_ext:
assert type_obj
dataclass_finalize(builder, cdef, dataclass_non_ext, type_obj)
else:
# Dynamically create the class via the type constructor
non_ext_class = load_non_ext_class(builder, ir, non_ext, cdef.line)
non_ext_class = load_decorated_class(builder, cdef, non_ext_class)
# Save the decorated class
builder.add(InitStatic(non_ext_class, cdef.name, builder.module_name, NAMESPACE_TYPE))
# Add the non-extension class to the dict
builder.primitive_op(dict_set_item_op,
[
builder.load_globals_dict(),
builder.load_static_unicode(cdef.name),
non_ext_class
], cdef.line)
# Cache any cachable class attributes
cache_class_attrs(builder, attrs_to_cache, cdef)
def get_sys_exc_info(builder: IRBuilder) -> List[Value]:
exc_info = builder.primitive_op(get_exc_info_op, [], -1)
return [builder.add(TupleGet(exc_info, i, -1)) for i in range(3)]
def try_finally_entry_blocks(builder: IRBuilder,
err_handler: BasicBlock,
return_entry: BasicBlock,
main_entry: BasicBlock,
finally_block: BasicBlock,
ret_reg: Optional[Register]) -> Value:
old_exc = builder.alloc_temp(exc_rtuple)
# Entry block for non-exceptional flow
builder.activate_block(main_entry)
if ret_reg:
builder.add(
Assign(
ret_reg,
builder.add(LoadErrorValue(builder.ret_types[-1]))
)
)
builder.goto(return_entry)
builder.activate_block(return_entry)
builder.add(Assign(old_exc, builder.add(LoadErrorValue(exc_rtuple))))
builder.goto(finally_block)
# Entry block for errors
builder.activate_block(err_handler)
if ret_reg:
builder.add(
Assign(
ret_reg,
builder.add(LoadErrorValue(builder.ret_types[-1]))
)
)
builder.add(Assign(old_exc, builder.primitive_op(error_catch_op, [], -1)))
builder.goto(finally_block)
return old_exc