See section 6.4.1 of the DWARF5 specification for details on each
pub const RegisterRule = union(enum)
pub const RegisterRule = union(enum) {
/// The spec says that the default rule for each column is the undefined rule.
/// However, it also allows ABI / compiler authors to specify alternate defaults, so
/// there is a distinction made here.
default,
undefined,
same_value,
/// offset(N)
offset: i64,
/// val_offset(N)
val_offset: i64,
/// register(R)
register: u8,
/// expression(E)
expression: []const u8,
/// val_expression(E)
val_expression: []const u8,
}