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

hdl.ast: guard rotate_* against 0-width values.

Browse source 
Fixes #808.
This commit is contained in:
Marcelina Kościelnicka 2023-06-07 12:49:41 +02:00 committed by Catherine
parent 656db317d2
commit a6e33abc5f
2 changed files with 12 additions and 2 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

6
amaranth/hdl/ast.py
View file

@ -516,7 +516,8 @@ class Value(metaclass=ABCMeta):
"""
if not isinstance(amount, int):
raise TypeError("Rotate amount must be an integer, not {!r}".format(amount))
amount %= len(self)
if len(self) != 0:
amount %= len(self)
return Cat(self[-amount:], self[:-amount]) # meow :3
def rotate_right(self, amount):
@ -534,7 +535,8 @@ class Value(metaclass=ABCMeta):
"""
if not isinstance(amount, int):
raise TypeError("Rotate amount must be an integer, not {!r}".format(amount))
amount %= len(self)
if len(self) != 0:
amount %= len(self)
return Cat(self[amount:], self[:amount])
def eq(self, value):

8
tests/test_hdl_ast.py
View file

@ -321,6 +321,10 @@ class ValueTestCase(FHDLTestCase):
"(cat (slice (const 9'd256) 1:9) (slice (const 9'd256) 0:1))")
self.assertRepr(Const(256).rotate_left(-7),
"(cat (slice (const 9'd256) 7:9) (slice (const 9'd256) 0:7))")
self.assertRepr(Const(0, 0).rotate_left(3),
"(cat (slice (const 0'd0) 0:0) (slice (const 0'd0) 0:0))")
self.assertRepr(Const(0, 0).rotate_left(-3),
"(cat (slice (const 0'd0) 0:0) (slice (const 0'd0) 0:0))")
def test_rotate_left_wrong(self):
with self.assertRaisesRegex(TypeError,
@ -336,6 +340,10 @@ class ValueTestCase(FHDLTestCase):
"(cat (slice (const 9'd256) 8:9) (slice (const 9'd256) 0:8))")
self.assertRepr(Const(256).rotate_right(-7),
"(cat (slice (const 9'd256) 2:9) (slice (const 9'd256) 0:2))")
self.assertRepr(Const(0, 0).rotate_right(3),
"(cat (slice (const 0'd0) 0:0) (slice (const 0'd0) 0:0))")
self.assertRepr(Const(0, 0).rotate_right(-3),
"(cat (slice (const 0'd0) 0:0) (slice (const 0'd0) 0:0))")
def test_rotate_right_wrong(self):
with self.assertRaisesRegex(TypeError,