litex/migen/flow/ala.py

82 lines
1.8 KiB
Python

from migen.fhdl.structure import *
from migen.fhdl.structure import _Operator
from migen.flow.actor import *
from migen.corelogic.record import *
from migen.corelogic import divider
class _SimpleBinary(CombinatorialActor):
def __init__(self, bv_op, bv_r=None):
self.bv_op = bv_op
if bv_r is None:
bv_r = self.__class__.get_result_bv(bv_op)
self.bv_r = bv_r
super().__init__(
("operands", Sink, [("a", bv_op), ("b", bv_op)]),
("result", Source, [("r", bv_r)]))
def get_process_fragment(self):
return Fragment([
self.token("result").r.eq(_Operator(self.op,
[self.token("operands").a, self.token("operands").b]))
])
class Add(_SimpleBinary):
op = "+"
def get_result_bv(bv):
return BV(bv.width+1, bv.signed)
class Sub(_SimpleBinary):
op = "-"
def get_result_bv(bv):
return BV(bv.width+1, bv.signed)
class Mul(_SimpleBinary):
op = "*"
def get_result_bv(bv):
return BV(2*bv.width, bv.signed)
class And(_SimpleBinary):
op = "&"
def get_result_bv(bv):
return bv
class Xor(_SimpleBinary):
op = "^"
def get_result_bv(bv):
return bv
class Or(_SimpleBinary):
op = "|"
def get_result_bv(bv):
return bv
class LT(_SimpleBinary):
op = "<"
def get_result_bv(bv):
return BV(1)
class LE(_SimpleBinary):
op = "<="
def get_result_bv(bv):
return BV(1)
class EQ(_SimpleBinary):
op = "=="
def get_result_bv(bv):
return BV(1)
class NE(_SimpleBinary):
op = "!="
def get_result_bv(bv):
return BV(1)
class DivMod(SequentialActor):
def __init__(self, width):
self.div = divider.Divider(width)
super().__init__(width,
("operands", Sink, [("dividend", self.div.dividend_i), ("divisor", self.div.divisor_i)]),
("result", Source, [("quotient", self.div.quotient_o), ("remainder", self.div.remainder_o)]))
def get_process_fragment(self):
return self.div.get_fragment() + Fragment([self.div.start_i.eq(self.trigger)])