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

hdl.ast: fix range handling in Shape.cast.

Browse source 
Fixes #803.
This commit is contained in:
Marcelina Kościelnicka 2023-06-07 11:45:56 +02:00 committed by Catherine
parent fcbc8bd46f
commit c7984463c7
2 changed files with 6 additions and 3 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

6
amaranth/hdl/ast.py
View file

@ -117,9 +117,9 @@ class Shape:
elif isinstance(obj, range): elif isinstance(obj, range):
if len(obj) == 0: if len(obj) == 0:
return Shape(0, obj.start < 0) return Shape(0, obj.start < 0)
signed = obj.start < 0 or (obj.stop - obj.step) < 0 signed = obj[0] < 0 or obj[-1] < 0
width = max(bits_for(obj.start, signed), width = max(bits_for(obj[0], signed),
bits_for(obj.stop - obj.step, signed)) bits_for(obj[-1], signed))
return Shape(width, signed) return Shape(width, signed)
elif isinstance(obj, type) and issubclass(obj, Enum): elif isinstance(obj, type) and issubclass(obj, Enum):
# For compatibility with third party enumerations, handle them as if they were # For compatibility with third party enumerations, handle them as if they were

3
tests/test_hdl_ast.py
View file

@ -117,6 +117,9 @@ class ShapeTestCase(FHDLTestCase):
s7 = Shape.cast(range(-1, -1)) s7 = Shape.cast(range(-1, -1))
self.assertEqual(s7.width, 0) self.assertEqual(s7.width, 0)
self.assertEqual(s7.signed, True) self.assertEqual(s7.signed, True)
s8 = Shape.cast(range(0, 10, 3))
self.assertEqual(s8.width, 4)
self.assertEqual(s8.signed, False)
def test_cast_enum(self): def test_cast_enum(self):
s1 = Shape.cast(UnsignedEnum) s1 = Shape.cast(UnsignedEnum)