def _check_function(f: Function, ctx: deduce.DeduceCtx) -> None:
"""Validates type annotations on parameters/return type of f are consistent.
Args:
f: The function to type check.
ctx: Wraps a node_to_type, a mapping of AST node to its deduced type;
(free-variable) references are resolved via this dictionary.
Raises:
XlsTypeError: When the return type deduced is inconsistent with the return
type annotation on "f".
"""
fn_name, _ = ctx.fn_stack[-1]
# First, get the types of the function's parametrics, args, and return type
if f.is_parametric() and f.name.identifier == fn_name:
# Parametric functions are evaluated per invocation. If we're currently
# inside of this function, it must mean that we already have the type
# signature and now we just need to evaluate the body.
assert f in ctx.node_to_type, f
annotated_return_type = ctx.node_to_type[f].return_type # pytype: disable=attribute-error
param_types = list(ctx.node_to_type[f].params) # pytype: disable=attribute-error
else:
logging.vlog(1, 'Type-checking sig for function: %s', f)
param_types = _check_function_params(f, ctx)
if f.is_parametric():
# We just needed the type signature so that we can instantiate this
# invocation. Let's return this for now and typecheck the body once we
# have symbolic bindings.
annotated_return_type = (deduce.deduce(f.return_type, ctx)
if f.return_type else ConcreteType.NIL)
ctx.node_to_type[f.name] = ctx.node_to_type[f] = FunctionType(
tuple(param_types), annotated_return_type)
return
logging.vlog(1, 'Type-checking body for function: %s', f)
# Second, typecheck the return type of the function.
# NOTE: if there is no annotated return type, we assume NIL.
annotated_return_type = (deduce.deduce(f.return_type, ctx)
if f.return_type else ConcreteType.NIL)
resolved_return_type = deduce.resolve(annotated_return_type, ctx)
# Third, typecheck the body of the function
body_return_type = deduce.deduce(f.body, ctx)
resolved_body_type = deduce.resolve(body_return_type, ctx)
# Finally, assert type consistency between body and annotated return type.
if resolved_return_type != resolved_body_type:
raise XlsTypeError(
f.body.span,
resolved_body_type,
resolved_return_type,
suffix='Return type of function body for "{}" did not match the '
'annotated return type.'.format(f.name.identifier))
ctx.node_to_type[f.name] = ctx.node_to_type[f] = FunctionType(
tuple(param_types), body_return_type)
def fsig(arg_types: ArgTypes, name: Text, span: Span, ctx: DeduceCtx,
_: Optional[ParametricBindings]) -> ConcreteType:
_Checker(arg_types, name, span).len(2).is_uN((0, 1))
return_type = BitsType(signed=False,
size=arg_types[0].get_total_bit_count() +
arg_types[1].get_total_bit_count())
return FunctionType(arg_types, return_type)
def fsig(arg_types: ArgTypes, name: Text, span: Span, ctx: DeduceCtx,
_: Optional[ParametricBindings]) -> ConcreteType:
_Checker(arg_types, name, span).len(1).is_array(0)
t = arg_types[0].get_element_type() # pytype: disable=attribute-error
e = TupleType((ConcreteType.U32, t))
return_type = ArrayType(e, arg_types[0].size) # pytype: disable=attribute-error
return FunctionType(arg_types, return_type)
def fsig(arg_types: ArgTypes, name: Text, span: Span, ctx: DeduceCtx,
_: Optional[ParametricBindings]) -> ConcreteType:
checker = _Checker(arg_types, name, span).len(3).is_array(0).is_uN(1)
checker.check_is_same(
arg_types[0].get_element_type(), arg_types[2], # pytype: disable=attribute-error
'Want argument 0 element type {0} to match argument 2 type {1}')
return FunctionType(arg_types, arg_types[0])
def fsig(arg_types: ArgTypes, name: Text, span: Span, ctx: DeduceCtx,
_: Optional[ParametricBindings]) -> ConcreteType:
checker = _Checker(arg_types, name, span).len(2).is_bits(0).is_array(1)
return_type = arg_types[1].get_element_type() # pytype: disable=attribute-error
checker.check_is_bits(return_type,
'Want arg 1 element type to be bits; got {0}')
return FunctionType(arg_types, return_type)
def fsig(arg_types: ArgTypes, name: Text, span: Span, ctx: DeduceCtx,
_: Optional[ParametricBindings]) -> ConcreteType:
checker = _Checker(arg_types, name,
span).len(3).is_array(0).is_uN(1).is_array(2)
checker.eq(
arg_types[0].get_element_type(), arg_types[2].get_element_type(), # pytype: disable=attribute-error
'Element type of argument 0 {0} should match element type of argument 2 {1}'
)
return FunctionType(arg_types, arg_types[2])
def fsig(
arg_types: ArgTypes, name: Text, span: Span, ctx: DeduceCtx,
parametric_bindings: Optional[ParametricBindings]
) -> Tuple[ConcreteType, parametric_instantiator.SymbolicBindings]:
"""Returns the inferred/checked return type for a map-style signature."""
logging.vlog(5, 'Instantiating for builtin %r @ %s', name, span)
_Checker(arg_types, name, span).len(2).is_array(0).is_fn(1, argc=1)
t = arg_types[0].get_element_type() # pytype: disable=attribute-error
u, symbolic_bindings = parametric_instantiator.instantiate_function(
span, arg_types[1], (t, ), ctx, parametric_bindings)
return_type = ArrayType(u, arg_types[0].size) # pytype: disable=attribute-error
return FunctionType(arg_types, return_type), symbolic_bindings
def fsig(arg_types: ArgTypes, name: Text, span: Span, ctx: DeduceCtx,
_: Optional[ParametricBindings]) -> ConcreteType:
"""Checks the type signature shown above and returns deduced output type."""
checker = _Checker(arg_types, name, span).len(2).is_bits(0).is_array(1)
arg0 = arg_types[0]
arg1 = arg_types[1]
assert isinstance(arg1, ArrayType), arg1
assert isinstance(arg1.size, int), arg1
return_type = arg1.element_type
checker.check_is_bits(return_type,
'Want arg 1 element type to be bits; got {0}')
checker.check_is_len(
arg1, arg0.size,
'bit width {target} must match {t} array size {t.size}')
return FunctionType(arg_types, return_type)
def fsig(arg_types: ArgTypes, name: Text, span: Span, ctx: DeduceCtx,
_: Optional[ParametricBindings]) -> ConcreteType:
_Checker(arg_types, name, span).len(3).is_uN((0, 1, 2))
return FunctionType(arg_types, arg_types[2])
def fsig(arg_types: ArgTypes, name: Text, span: Span, ctx: DeduceCtx,
_: Optional[ParametricBindings]) -> ConcreteType:
_Checker(arg_types, name, span).len(2).is_bits(0).is_same(0, 1)
return FunctionType(arg_types, ConcreteType.U1)