1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
|
{-# LANGUAGE CPP #-}
-- | Free regs map for SPARC
module GHC.CmmToAsm.Reg.Linear.SPARC where
import GHC.Prelude
import GHC.CmmToAsm.SPARC.Regs
import GHC.Platform.Reg.Class
import GHC.Platform.Reg
import GHC.Platform.Regs
import GHC.Utils.Outputable
import GHC.Utils.Panic
import GHC.Platform
import Data.Word
import Data.Bits
--------------------------------------------------------------------------------
-- SPARC is like PPC, except for twinning of floating point regs.
-- When we allocate a double reg we must take an even numbered
-- float reg, as well as the one after it.
-- Holds bitmaps showing what registers are currently allocated.
-- The float and double reg bitmaps overlap, but we only alloc
-- float regs into the float map, and double regs into the double map.
--
-- Free regs have a bit set in the corresponding bitmap.
--
data FreeRegs
= FreeRegs
!Word32 -- int reg bitmap regs 0..31
!Word32 -- float reg bitmap regs 32..63
!Word32 -- double reg bitmap regs 32..63
instance Show FreeRegs where
show = showFreeRegs
instance Outputable FreeRegs where
ppr = text . showFreeRegs
-- | A reg map where no regs are free to be allocated.
noFreeRegs :: FreeRegs
noFreeRegs = FreeRegs 0 0 0
-- | The initial set of free regs.
initFreeRegs :: Platform -> FreeRegs
initFreeRegs platform
= foldl' (flip $ releaseReg platform) noFreeRegs allocatableRegs
-- | Get all the free registers of this class.
getFreeRegs :: RegClass -> FreeRegs -> [RealReg] -- lazily
getFreeRegs cls (FreeRegs g f d)
| RcInteger <- cls = map RealRegSingle $ go 1 g 1 0
| RcFloat <- cls = map RealRegSingle $ go 1 f 1 32
| RcDouble <- cls = map (\i -> RealRegPair i (i+1)) $ go 2 d 1 32
#if __GLASGOW_HASKELL__ <= 810
| otherwise = pprPanic "RegAllocLinear.getFreeRegs: Bad register class " (ppr cls)
#endif
where
go _ _ 0 _
= []
go step bitmap mask ix
| bitmap .&. mask /= 0
= ix : (go step bitmap (mask `shiftL` step) $! ix + step)
| otherwise
= go step bitmap (mask `shiftL` step) $! ix + step
-- | Grab a register.
allocateReg :: Platform -> RealReg -> FreeRegs -> FreeRegs
allocateReg platform
reg@(RealRegSingle r)
(FreeRegs g f d)
-- can't allocate free regs
| not $ freeReg platform r
= pprPanic "SPARC.FreeRegs.allocateReg: not allocating pinned reg" (ppr reg)
-- a general purpose reg
| r <= 31
= let mask = complement (bitMask r)
in FreeRegs
(g .&. mask)
f
d
-- a float reg
| r >= 32, r <= 63
= let mask = complement (bitMask (r - 32))
-- the mask of the double this FP reg aliases
maskLow = if r `mod` 2 == 0
then complement (bitMask (r - 32))
else complement (bitMask (r - 32 - 1))
in FreeRegs
g
(f .&. mask)
(d .&. maskLow)
| otherwise
= pprPanic "SPARC.FreeRegs.releaseReg: not allocating bad reg" (ppr reg)
allocateReg _
reg@(RealRegPair r1 r2)
(FreeRegs g f d)
| r1 >= 32, r1 <= 63, r1 `mod` 2 == 0
, r2 >= 32, r2 <= 63
= let mask1 = complement (bitMask (r1 - 32))
mask2 = complement (bitMask (r2 - 32))
in
FreeRegs
g
((f .&. mask1) .&. mask2)
(d .&. mask1)
| otherwise
= pprPanic "SPARC.FreeRegs.releaseReg: not allocating bad reg" (ppr reg)
-- | Release a register from allocation.
-- The register liveness information says that most regs die after a C call,
-- but we still don't want to allocate to some of them.
--
releaseReg :: Platform -> RealReg -> FreeRegs -> FreeRegs
releaseReg platform
reg@(RealRegSingle r)
regs@(FreeRegs g f d)
-- don't release pinned reg
| not $ freeReg platform r
= regs
-- a general purpose reg
| r <= 31
= let mask = bitMask r
in FreeRegs (g .|. mask) f d
-- a float reg
| r >= 32, r <= 63
= let mask = bitMask (r - 32)
-- the mask of the double this FP reg aliases
maskLow = if r `mod` 2 == 0
then bitMask (r - 32)
else bitMask (r - 32 - 1)
in FreeRegs
g
(f .|. mask)
(d .|. maskLow)
| otherwise
= pprPanic "SPARC.FreeRegs.releaseReg: not releasing bad reg" (ppr reg)
releaseReg _
reg@(RealRegPair r1 r2)
(FreeRegs g f d)
| r1 >= 32, r1 <= 63, r1 `mod` 2 == 0
, r2 >= 32, r2 <= 63
= let mask1 = bitMask (r1 - 32)
mask2 = bitMask (r2 - 32)
in
FreeRegs
g
((f .|. mask1) .|. mask2)
(d .|. mask1)
| otherwise
= pprPanic "SPARC.FreeRegs.releaseReg: not releasing bad reg" (ppr reg)
bitMask :: Int -> Word32
bitMask n = 1 `shiftL` n
showFreeRegs :: FreeRegs -> String
showFreeRegs regs
= "FreeRegs\n"
++ " integer: " ++ (show $ getFreeRegs RcInteger regs) ++ "\n"
++ " float: " ++ (show $ getFreeRegs RcFloat regs) ++ "\n"
++ " double: " ++ (show $ getFreeRegs RcDouble regs) ++ "\n"
|
