usb-tools/amaranth
1
0
Fork 0
Code Issues Pull requests Actions Packages Projects Releases Wiki Activity

back.pysim: implement Part.

Browse source
This commit is contained in:
whitequark 2018-12-15 20:58:06 +00:00
parent 1adf58f561
commit 20a04bca88
3 changed files with 12 additions and 2 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

6
nmigen/back/pysim.py
View file

@ -118,7 +118,11 @@ class _RHSValueCompiler(ValueTransformer):
return lambda state: normalize((arg(state) >> shift) & mask, shape)
def on_Part(self, value):
raise NotImplementedError
shape = value.shape()
arg = self(value.value)
shift = self(value.offset)
mask = (1 << value.width) - 1
return lambda state: normalize((arg(state) >> shift(state)) & mask, shape)
def on_Cat(self, value):
shape = value.shape()

2
nmigen/hdl/ast.py
View file

@ -405,7 +405,7 @@ class Part(Value):
return self.value._lhs_signals()
def _rhs_signals(self):
return self.value._rhs_signals()
return self.value._rhs_signals() | self.offset._rhs_signals()
def __repr__(self):
return "(part {} {} {})".format(repr(self.value), repr(self.offset), self.width)

6
nmigen/test/test_sim.py
View file

@ -130,6 +130,12 @@ class SimulatorUnitTestCase(FHDLTestCase):
stmt2 = lambda a: a[2:4]
self.assertOperator(stmt2, [C(0b10110100, 8)], C(0b01, 2))
def test_part(self):
stmt = lambda a, b: a.part(b, 3)
self.assertOperator(stmt, [C(0b10110100, 8), C(0)], C(0b100, 3))
self.assertOperator(stmt, [C(0b10110100, 8), C(2)], C(0b101, 3))
self.assertOperator(stmt, [C(0b10110100, 8), C(3)], C(0b110, 3))
def test_cat(self):
self.assertOperator(Cat, [C(0b10, 2), C(0b01, 2)], C(0b0110, 4))