def chain(n, state_name='x', action='a', start=None, clip=True, can_stay=True):
if start is None:
start = n // 2
else:
start -= 1
start = encode_int(n, 1 << start, signed=False)
x = atom(n, state_name, signed=False)
a = atom(2, action, signed=False)
backward, forward = a[0], a[1]
x2 = ite(forward, x << 1, x >> 1)
stay = atom(1, 1, signed=False)
if clip:
stay = (x2 == 0)
if can_stay:
stay |= ~(forward | backward)
if clip or can_stay:
x2 = ite(stay, x, x2)
circ = x2.aigbv['o', {x2.output: state_name}]
return circ.feedback(inputs=[state_name],
outputs=[state_name],
initials=[start],
keep_outputs=True)
def encode_inputs(inputs, imap, encodings):
for key, val in inputs.items():
size = imap[key].size
if key in encodings: # Convert to tuple of bools.
val = encodings[key].encode(val)
assert isinstance(val, int)
val = BV.encode_int(size, val, signed=False)
assert len(val) == size
yield key, val
def chain(n, state_name='x', action='H'):
bits = n + 1
start = encode_int(bits, 1, signed=False)
x = atom(bits, state_name, signed=False)
forward = atom(1, action, signed=False)
x2 = ite(forward, x << 1, x)
circ = x2.aigbv['o', {x2.output: state_name}]
return circ.feedback(inputs=[state_name],
outputs=[state_name],
latches=[f"{state_name}_prev"],
initials=[start],
keep_outputs=True)
def _encode_wiring(self, wiring):
if 'init' not in wiring:
return wiring
wiring = dict(wiring) # copy to avoid side-effect.
name, init = wiring['input'], wiring['init']
if wiring.get('input_encoding', True):
encodings = self.input_encodings
else:
encodings = self.output_encodings
if name in encodings:
init = wiring['encoding'].encode(init)
assert isinstance(init, int)
size = self.circ.imap[name].size
wiring['init'] = BV.encode_int(size, init, signed=False)
return wiring
def encode_state(x, y):
x, y = [BV.encode_int(8, 1 << (v - 1), signed=False) for v in (x, y)]
return {'x': tuple(x), 'y': tuple(y)}