e8fd6cb7e1a5c7ca2c535a6213e2a791684577ee
2 from soc
.decoder
.selectable_int
import SelectableInt
7 return (value
& (sign
- 1)) - (value
& sign
)
11 """ extends sign bit out from current MSB to all 256 bits
13 assert isinstance(value
, SelectableInt
)
14 return SelectableInt(exts(value
.value
, value
.bits
) & ((1 << 256)-1), 256)
17 """ extends sign bit out from current MSB to 64 bits
19 assert isinstance(value
, SelectableInt
)
20 return SelectableInt(exts(value
.value
, value
.bits
) & ((1 << 64)-1), 64)
23 # XXX should this explicitly extend from 32 to 64?
25 if isinstance(value
, SelectableInt
):
27 return SelectableInt(value
& ((1<<32)-1), 64)
30 def rotl(value
, bits
, wordlen
):
31 if isinstance(bits
, SelectableInt
):
33 mask
= (1 << wordlen
) - 1
34 bits
= bits
& (wordlen
- 1)
35 return ((value
<< bits
) |
(value
>> (wordlen
-bits
))) & mask
38 def ROTL64(value
, bits
):
39 return rotl(value
, bits
, 64)
42 def ROTL32(value
, bits
):
43 if isinstance(value
, SelectableInt
):
44 value
= SelectableInt(value
.value
, 64)
45 return rotl(value |
(value
<< 32), bits
, 64)
49 if isinstance(x
, SelectableInt
):
51 if isinstance(y
, SelectableInt
):
56 mask_a
= ((1 << x
) - 1) & ((1 << 64) - 1)
57 mask_b
= ((1 << y
) - 1) & ((1 << 64) - 1)
63 mask_a
= ((1 << x
) - 1) & ((1 << 64) - 1)
64 mask_b
= (~
((1 << y
) - 1)) & ((1 << 64) - 1)
65 return mask_a ^ mask_b
68 return SelectableInt((a
!= b
), bits
=1)
71 return SelectableInt((a
== b
), bits
=1)
74 return SelectableInt((a
> b
), bits
=1)
77 return SelectableInt((a
>= b
), bits
=1)
80 return SelectableInt((a
< b
), bits
=1)
83 return SelectableInt((a
<= b
), bits
=1)
88 # For these tests I tried to find power instructions that would let me
89 # isolate each of these helper operations. So for instance, when I was
90 # testing the MASK() function, I chose rlwinm and rldicl because if I
91 # set the shift equal to 0 and passed in a value of all ones, the
92 # result I got would be exactly the same as the output of MASK()
94 class HelperTests(unittest
.TestCase
):
96 # Verified using rlwinm, rldicl, rldicr in qemu
98 # rlwinm reg, 1, 0, 5, 15
99 self
.assertHex(MASK(5+32, 15+32), 0x7ff0000)
100 # rlwinm reg, 1, 0, 15, 5
101 self
.assertHex(MASK(15+32, 5+32), 0xfffffffffc01ffff)
102 self
.assertHex(MASK(30+32, 2+32), 0xffffffffe0000003)
103 # rldicl reg, 1, 0, 37
104 self
.assertHex(MASK(37, 63), 0x7ffffff)
105 self
.assertHex(MASK(10, 63), 0x3fffffffffffff)
106 self
.assertHex(MASK(58, 63), 0x3f)
107 # rldicr reg, 1, 0, 37
108 self
.assertHex(MASK(0, 37), 0xfffffffffc000000)
109 self
.assertHex(MASK(0, 10), 0xffe0000000000000)
110 self
.assertHex(MASK(0, 58), 0xffffffffffffffe0)
114 self
.assertHex(MASK(32, 63-5), 0xffffffe0)
116 self
.assertHex(MASK(32, 33), 0xc0000000)
117 self
.assertHex(MASK(32, 32), 0x80000000)
118 self
.assertHex(MASK(33, 33), 0x40000000)
120 def test_ROTL64(self
):
121 # r1 = 0xdeadbeef12345678
122 value
= 0xdeadbeef12345678
124 # rldicl reg, 1, 10, 0
125 self
.assertHex(ROTL64(value
, 10), 0xb6fbbc48d159e37a)
126 # rldicl reg, 1, 35, 0
127 self
.assertHex(ROTL64(value
, 35), 0x91a2b3c6f56df778)
128 self
.assertHex(ROTL64(value
, 58), 0xe37ab6fbbc48d159)
129 self
.assertHex(ROTL64(value
, 22), 0xbbc48d159e37ab6f)
131 def test_ROTL32(self
):
135 # rlwinm reg, 1, 10, 0, 31
136 self
.assertHex(ROTL32(value
, 10), 0xb6fbbf7a)
137 # rlwinm reg, 1, 17, 0, 31
138 self
.assertHex(ROTL32(value
, 17), 0x7ddfbd5b)
139 self
.assertHex(ROTL32(value
, 25), 0xdfbd5b7d)
140 self
.assertHex(ROTL32(value
, 30), 0xf7ab6fbb)
142 def test_EXTS64(self
):
143 value_a
= SelectableInt(0xdeadbeef, 32) # r1
144 value_b
= SelectableInt(0x73123456, 32) # r2
145 value_c
= SelectableInt(0x80000000, 32) # r3
148 self
.assertHex(EXTS64(value_a
), 0xffffffffdeadbeef)
150 self
.assertHex(EXTS64(value_b
), SelectableInt(value_b
.value
, 64))
152 self
.assertHex(EXTS64(value_c
), 0xffffffff80000000)
154 def assertHex(self
, a
, b
):
156 if isinstance(a
, SelectableInt
):
159 if isinstance(b
, SelectableInt
):
161 msg
= "{:x} != {:x}".format(a_val
, b_val
)
162 return self
.assertEqual(a
, b
, msg
)
165 if __name__
== '__main__':
166 print (SelectableInt
.__bases
__)