def sign_ext(self, new_bit_count: int) -> 'Bits':
value = self.value
if self.get_sign_bit() and new_bit_count >= self.bit_count:
value |= bit_helpers.to_mask(new_bit_count -
self.bit_count) << self.bit_count
return Bits(bit_count=new_bit_count,
value=value & bit_helpers.to_mask(new_bit_count))
def zero_ext() -> Value:
assert isinstance(type_, BitsType)
constructor = Value.make_sbits if type_.signed else Value.make_ubits
bit_count = type_.get_total_bit_count()
return constructor(
bit_count,
value.get_bits_value() & bit_helpers.to_mask(bit_count))
def do_shra(lhs: int, rhs: int):
if (lhs >> (self.bit_count - 1)) & 1:
if rhs >= self.bit_count:
return self.get_mask()
return (lhs >> rhs) | (
bit_helpers.to_mask(rhs) << (self.bit_count - rhs))
else:
if rhs >= self.bit_count:
return 0
return lhs >> rhs
def make_bit_patterns(bit_count: int) -> Tuple[int, ...]:
"""Creates a sequence of interesting bit patterns at a given bit count."""
if bit_count == 0:
return (0,)
all_ones = int('0b' + '1' * bit_count, 2)
all_but_high_ones = int('0b0' + '1' * (bit_count - 1), 2)
off_on = int(
'0b' + '01' * (bit_count // 2) + ('0' if bit_count % 2 != 0 else ''), 2)
on_off = int(
'0b' + '10' * (bit_count // 2) + ('1' if bit_count % 2 != 0 else ''), 2)
one_hots = tuple(
int('0b{}1{}'.format('0' * pos, '0' * (bit_count - pos - 1)), 2)
for pos in range(bit_count))
zero = 0
result = (all_ones, all_but_high_ones, off_on, on_off, zero) + one_hots
assert all(x & bit_helpers.to_mask(bit_count) == x for x in result)
return result
def get_mask(self) -> int: return bit_helpers.to_mask(self.bit_count)
def zero_ext(self, new_bit_count: int) -> 'Bits':
return Bits(
bit_count=new_bit_count,
value=self.value & bit_helpers.to_mask(new_bit_count))
def get_lsb_slice(self, count: int) -> 'Bits': return Bits(bit_count=count, value=self.value & bit_helpers.to_mask(count))