67 lines
1.4 KiB
Python
67 lines
1.4 KiB
Python
from migen.fhdl.structure import *
|
|
from migen.fhdl.structure import _Operator
|
|
|
|
def multimux(sel, inputs, output):
|
|
n = len(inputs)
|
|
i = 0
|
|
statements = []
|
|
for osig in output:
|
|
choices = [x[i] for x in inputs]
|
|
cases = [[Constant(j, sel.bv), osig.eq(choices[j])] for j in range(n)]
|
|
cases[n-1][0] = Default()
|
|
statements.append(Case(sel, *cases))
|
|
i += 1
|
|
return statements
|
|
|
|
def optree(op, operands, lb=None, ub=None, default=None):
|
|
if lb is None:
|
|
lb = 0
|
|
if ub is None:
|
|
ub = len(operands)
|
|
l = ub - lb
|
|
if l == 0:
|
|
if default is None:
|
|
raise AttributeError
|
|
else:
|
|
return default
|
|
elif l == 1:
|
|
return operands[lb]
|
|
else:
|
|
s = lb + l//2
|
|
return _Operator(op,
|
|
[optree(op, operands, lb, s, default),
|
|
optree(op, operands, s, ub, default)])
|
|
|
|
def split(v, *counts):
|
|
r = []
|
|
offset = 0
|
|
for n in counts:
|
|
r.append(v[offset:offset+n])
|
|
offset += n
|
|
return tuple(r)
|
|
|
|
def displacer(signal, shift, output, n=None, reverse=False):
|
|
if n is None:
|
|
n = 2**shift.bv.width
|
|
w = signal.bv.width
|
|
if reverse:
|
|
r = reversed(range(n))
|
|
else:
|
|
r = range(n)
|
|
l = [Replicate(shift == i, w) & signal for i in r]
|
|
return output.eq(Cat(*l))
|
|
|
|
def chooser(signal, shift, output, n=None, reverse=False):
|
|
if n is None:
|
|
n = 2**shift.bv.width
|
|
w = output.bv.width
|
|
cases = []
|
|
for i in range(n):
|
|
if reverse:
|
|
s = n - i - 1
|
|
else:
|
|
s = i
|
|
cases.append([Constant(i, shift.bv), output.eq(signal[s*w:(s+1)*w])])
|
|
cases[n-1][0] = Default()
|
|
return Case(shift, *cases)
|