Add support for `maximum_bits` and `is_signed` on `enum`s.
diff --git a/compiler/front_end/attribute_checker.py b/compiler/front_end/attribute_checker.py
index 92dd939..27e6722 100644
--- a/compiler/front_end/attribute_checker.py
+++ b/compiler/front_end/attribute_checker.py
@@ -35,6 +35,10 @@
_MUST_BE_CONSTANT_MESSAGE = "Attribute '{name}' must have a constant value."
+# Default value for maximum_bits on an `enum`.
+_DEFAULT_ENUM_MAXIMUM_BITS = 64
+
+
# Attribute type checkers
def _is_constant_boolean(attr, module_source_file):
"""Checks if the given attr is a constant boolean."""
@@ -108,8 +112,10 @@
_ATTRIBUTE_TYPES = {
("", attributes.ADDRESSABLE_UNIT_SIZE): _is_constant_integer,
("", attributes.BYTE_ORDER): _is_valid_byte_order,
+ ("", attributes.ENUM_MAXIMUM_BITS): _is_constant_integer,
("", attributes.FIXED_SIZE): _is_constant_integer,
("", attributes.IS_INTEGER): _is_constant_boolean,
+ ("", attributes.IS_SIGNED): _is_constant_boolean,
("", attributes.REQUIRES): _is_boolean,
("", attributes.STATIC_REQUIREMENTS): _is_boolean,
("", attributes.TEXT_OUTPUT): _is_valid_text_output,
@@ -125,16 +131,15 @@
_BITS_ATTRIBUTES = {
("", attributes.FIXED_SIZE, False),
("", attributes.REQUIRES, False),
- ("", attributes.STATIC_REQUIREMENTS, False),
}
_STRUCT_ATTRIBUTES = {
("", attributes.FIXED_SIZE, False),
("", attributes.BYTE_ORDER, True),
("", attributes.REQUIRES, False),
- ("", attributes.STATIC_REQUIREMENTS, False),
}
_ENUM_ATTRIBUTES = {
- ("", attributes.STATIC_REQUIREMENTS, False),
+ ("", attributes.ENUM_MAXIMUM_BITS, False),
+ ("", attributes.IS_SIGNED, False),
}
_EXTERNAL_ATTRIBUTES = {
("", attributes.ADDRESSABLE_UNIT_SIZE, False),
@@ -166,7 +171,23 @@
maximum_value=str(value))),
source_location=source_location),
source_location=source_location)
- return ir_pb2.Attribute(name=ir_pb2.Word(text=name),
+ return ir_pb2.Attribute(name=ir_pb2.Word(text=name,
+ source_location=source_location),
+ value=attr_value,
+ source_location=source_location)
+
+
+def _construct_boolean_attribute(name, value, source_location):
+ """Constructs a boolean Attribute with the given name and value."""
+ attr_value = ir_pb2.AttributeValue(
+ expression=ir_pb2.Expression(
+ boolean_constant=ir_pb2.BooleanConstant(
+ value=value, source_location=source_location),
+ type=ir_pb2.ExpressionType(boolean=ir_pb2.BooleanType(value=value)),
+ source_location=source_location),
+ source_location=source_location)
+ return ir_pb2.Attribute(name=ir_pb2.Word(text=name,
+ source_location=source_location),
value=attr_value,
source_location=source_location)
@@ -425,6 +446,30 @@
# _verify_addressable_unit_attribute_on_external, below.
+def _add_missing_width_and_sign_attributes_on_enum(enum, type_definition):
+ """Sets the maximum_bits and is_signed attributes for an enum, if needed."""
+ max_bits_attr = ir_util.get_integer_attribute(type_definition.attribute,
+ attributes.ENUM_MAXIMUM_BITS)
+ if max_bits_attr is None:
+ type_definition.attribute.extend([
+ _construct_integer_attribute(attributes.ENUM_MAXIMUM_BITS,
+ _DEFAULT_ENUM_MAXIMUM_BITS,
+ type_definition.source_location)])
+ signed_attr = ir_util.get_boolean_attribute(type_definition.attribute,
+ attributes.IS_SIGNED)
+ if signed_attr is None:
+ for value in enum.value:
+ numeric_value = ir_util.constant_value(value.value)
+ if numeric_value < 0:
+ is_signed = True
+ break
+ else:
+ is_signed = False
+ type_definition.attribute.extend([
+ _construct_boolean_attribute(attributes.IS_SIGNED, is_signed,
+ type_definition.source_location)])
+
+
def _verify_byte_order_attribute_on_field(field, type_definition,
source_file_name, ir, errors):
"""Verifies the byte_order attribute on the given field."""
@@ -496,6 +541,22 @@
])
+def _verify_width_attribute_on_enum(enum, type_definition, source_file_name,
+ errors):
+ """Verifies the maximum_bits attribute for an enum TypeDefinition."""
+ max_bits_value = ir_util.get_integer_attribute(type_definition.attribute,
+ attributes.ENUM_MAXIMUM_BITS)
+ # The attribute should already have been defaulted, if not originally present.
+ assert max_bits_value is not None, "maximum_bits not set"
+ if max_bits_value > 64 or max_bits_value < 1:
+ max_bits_attr = ir_util.get_attribute(type_definition.attribute,
+ attributes.ENUM_MAXIMUM_BITS)
+ errors.append([
+ error.error(source_file_name, max_bits_attr.source_location,
+ "'maximum_bits' on an 'enum' must be between 1 and 64.")
+ ])
+
+
def _gather_default_attributes(obj, defaults):
defaults = defaults.copy()
for attr in obj.attribute:
@@ -512,6 +573,8 @@
traverse_ir.fast_traverse_ir_top_down(
ir, [ir_pb2.External], _add_addressable_unit_to_external)
traverse_ir.fast_traverse_ir_top_down(
+ ir, [ir_pb2.Enum], _add_missing_width_and_sign_attributes_on_enum)
+ traverse_ir.fast_traverse_ir_top_down(
ir, [ir_pb2.Structure], _add_missing_size_attributes_on_structure,
incidental_actions={
ir_pb2.Module: _gather_default_attributes,
@@ -544,6 +607,9 @@
ir, [ir_pb2.Structure], _verify_size_attributes_on_structure,
parameters={"errors": errors})
traverse_ir.fast_traverse_ir_top_down(
+ ir, [ir_pb2.Enum], _verify_width_attribute_on_enum,
+ parameters={"errors": errors})
+ traverse_ir.fast_traverse_ir_top_down(
ir, [ir_pb2.External], _verify_addressable_unit_attribute_on_external,
parameters={"errors": errors})
traverse_ir.fast_traverse_ir_top_down(
