2 from soc
.decoder
.selectable_int
import SelectableInt
, onebit
3 from nmutil
.divmod import trunc_div
, trunc_rem
4 from soc
.decoder
.selectable_int
import selectltu
as ltu
5 from soc
.decoder
.selectable_int
import selectgtu
as gtu
9 * https://bugs.libre-soc.org/show_bug.cgi?id=324 - add trunc_div and trunc_rem
12 def exts(value
, bits
):
13 sign
= 1 << (bits
- 1)
14 return (value
& (sign
- 1)) - (value
& sign
)
18 """ extends sign bit out from current MSB to all 256 bits
20 assert isinstance(value
, SelectableInt
)
21 return SelectableInt(exts(value
.value
, value
.bits
) & ((1 << 256)-1), 256)
24 """ extends sign bit out from current MSB to 64 bits
26 assert isinstance(value
, SelectableInt
)
27 return SelectableInt(exts(value
.value
, value
.bits
) & ((1 << 64)-1), 64)
30 # signed version of MUL
32 a_s
= a
.value
& (1<<(a
.bits
-1)) != 0
33 b_s
= b
.value
& (1<<(b
.bits
-1)) != 0
34 result
= abs(a
) * abs(b
)
35 print ("MULS", result
, a_s
, b_s
)
41 # XXX should this explicitly extend from 32 to 64?
43 if isinstance(value
, SelectableInt
):
45 return SelectableInt(value
& ((1<<32)-1), 64)
48 def rotl(value
, bits
, wordlen
):
49 if isinstance(bits
, SelectableInt
):
51 mask
= (1 << wordlen
) - 1
52 bits
= bits
& (wordlen
- 1)
53 return ((value
<< bits
) |
(value
>> (wordlen
-bits
))) & mask
56 def ROTL64(value
, bits
):
57 return rotl(value
, bits
, 64)
60 def ROTL32(value
, bits
):
61 if isinstance(value
, SelectableInt
):
62 value
= SelectableInt(value
.value
, 64)
63 return rotl(value |
(value
<< 32), bits
, 64)
67 if isinstance(x
, SelectableInt
):
69 if isinstance(y
, SelectableInt
):
74 mask_a
= ((1 << x
) - 1) & ((1 << 64) - 1)
75 mask_b
= ((1 << y
) - 1) & ((1 << 64) - 1)
81 mask_a
= ((1 << x
) - 1) & ((1 << 64) - 1)
82 mask_b
= (~
((1 << y
) - 1)) & ((1 << 64) - 1)
83 return mask_a ^ mask_b
101 return onebit(a
<= b
)
106 # For these tests I tried to find power instructions that would let me
107 # isolate each of these helper operations. So for instance, when I was
108 # testing the MASK() function, I chose rlwinm and rldicl because if I
109 # set the shift equal to 0 and passed in a value of all ones, the
110 # result I got would be exactly the same as the output of MASK()
112 class HelperTests(unittest
.TestCase
):
114 # Verified using rlwinm, rldicl, rldicr in qemu
116 # rlwinm reg, 1, 0, 5, 15
117 self
.assertHex(MASK(5+32, 15+32), 0x7ff0000)
118 # rlwinm reg, 1, 0, 15, 5
119 self
.assertHex(MASK(15+32, 5+32), 0xfffffffffc01ffff)
120 self
.assertHex(MASK(30+32, 2+32), 0xffffffffe0000003)
121 # rldicl reg, 1, 0, 37
122 self
.assertHex(MASK(37, 63), 0x7ffffff)
123 self
.assertHex(MASK(10, 63), 0x3fffffffffffff)
124 self
.assertHex(MASK(58, 63), 0x3f)
125 # rldicr reg, 1, 0, 37
126 self
.assertHex(MASK(0, 37), 0xfffffffffc000000)
127 self
.assertHex(MASK(0, 10), 0xffe0000000000000)
128 self
.assertHex(MASK(0, 58), 0xffffffffffffffe0)
132 self
.assertHex(MASK(32, 63-5), 0xffffffe0)
134 self
.assertHex(MASK(32, 33), 0xc0000000)
135 self
.assertHex(MASK(32, 32), 0x80000000)
136 self
.assertHex(MASK(33, 33), 0x40000000)
138 def test_ROTL64(self
):
139 # r1 = 0xdeadbeef12345678
140 value
= 0xdeadbeef12345678
142 # rldicl reg, 1, 10, 0
143 self
.assertHex(ROTL64(value
, 10), 0xb6fbbc48d159e37a)
144 # rldicl reg, 1, 35, 0
145 self
.assertHex(ROTL64(value
, 35), 0x91a2b3c6f56df778)
146 self
.assertHex(ROTL64(value
, 58), 0xe37ab6fbbc48d159)
147 self
.assertHex(ROTL64(value
, 22), 0xbbc48d159e37ab6f)
149 def test_ROTL32(self
):
153 # rlwinm reg, 1, 10, 0, 31
154 self
.assertHex(ROTL32(value
, 10), 0xb6fbbf7a)
155 # rlwinm reg, 1, 17, 0, 31
156 self
.assertHex(ROTL32(value
, 17), 0x7ddfbd5b)
157 self
.assertHex(ROTL32(value
, 25), 0xdfbd5b7d)
158 self
.assertHex(ROTL32(value
, 30), 0xf7ab6fbb)
160 def test_EXTS64(self
):
161 value_a
= SelectableInt(0xdeadbeef, 32) # r1
162 value_b
= SelectableInt(0x73123456, 32) # r2
163 value_c
= SelectableInt(0x80000000, 32) # r3
166 self
.assertHex(EXTS64(value_a
), 0xffffffffdeadbeef)
168 self
.assertHex(EXTS64(value_b
), SelectableInt(value_b
.value
, 64))
170 self
.assertHex(EXTS64(value_c
), 0xffffffff80000000)
172 def assertHex(self
, a
, b
):
174 if isinstance(a
, SelectableInt
):
177 if isinstance(b
, SelectableInt
):
179 msg
= "{:x} != {:x}".format(a_val
, b_val
)
180 return self
.assertEqual(a
, b
, msg
)
183 if __name__
== '__main__':
184 print (SelectableInt
.__bases
__)