import Data.Word
import Data.Bits
+#include "../includes/MachRegs.h"
-- -----------------------------------------------------------------------------
-- The free register set
allocateReg f r = filter (/= r) f
-}
-#if defined(powerpc_TARGET_ARCH)
+#if defined(powerpc_TARGET_ARCH)
-- The PowerPC has 32 integer and 32 floating point registers.
-- This is 32bit PowerPC, so Word64 is inefficient - two Word32s are much
getFreeRegs cls (FreeRegs g f)
| RcDouble <- cls = go f (0x80000000) 63
| RcInteger <- cls = go g (0x80000000) 31
- | otherwise = pprPanic "RegAllocLinear.getFreeRegs: Bad cls" (ppr cls)
+ | otherwise = pprPanic "RegAllocLinear.getFreeRegs: Bad register class" (ppr cls)
where
go _ 0 _ = []
go x m i | x .&. m /= 0 = i : (go x (m `shiftR` 1) $! i-1)
| r > 31 = FreeRegs g (f .&. complement (1 `shiftL` (fromIntegral r - 32)))
| otherwise = FreeRegs (g .&. complement (1 `shiftL` fromIntegral r)) f
-#else
+
+#elif defined(sparc_TARGET_ARCH)
+--------------------------------------------------------------------------------
+-- 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
+ deriving( Show )
+
+
+-- | A reg map where no regs are free to be allocated.
+noFreeRegs :: FreeRegs
+noFreeRegs = FreeRegs 0 0 0
+
+
+-- | The initial set of free regs.
+-- Don't treat the top half of reg pairs we're using as doubles as being free.
+initFreeRegs :: FreeRegs
+initFreeRegs
+ = regs
+ where
+-- freeDouble = getFreeRegs RcDouble regs
+ regs = foldr releaseReg noFreeRegs allocable
+ allocable = allocatableRegs \\ doublePairs
+ doublePairs = [43, 45, 47, 49, 51, 53]
+
+
+-- | Get all the free registers of this class.
+getFreeRegs :: RegClass -> FreeRegs -> [RegNo] -- lazilly
+getFreeRegs cls (FreeRegs g f d)
+ | RcInteger <- cls = go g 1 0
+ | RcFloat <- cls = go f 1 32
+ | RcDouble <- cls = go d 1 32
+ | otherwise = pprPanic "RegAllocLinear.getFreeRegs: Bad register class " (ppr cls)
+ where
+ go _ 0 _ = []
+ go x m i | x .&. m /= 0 = i : (go x (m `shiftL` 1) $! i+1)
+ | otherwise = go x (m `shiftL` 1) $! i+1
+{-
+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"
+-}
+
+{-
+-- | Check whether a reg is free
+regIsFree :: RegNo -> FreeRegs -> Bool
+regIsFree r (FreeRegs g f d)
+
+ -- a general purpose reg
+ | r <= 31
+ , mask <- 1 `shiftL` fromIntegral r
+ = g .&. mask /= 0
+
+ -- use the first 22 float regs as double precision
+ | r >= 32
+ , r <= 53
+ , mask <- 1 `shiftL` (fromIntegral r - 32)
+ = d .&. mask /= 0
+
+ -- use the last 10 float regs as single precision
+ | otherwise
+ , mask <- 1 `shiftL` (fromIntegral r - 32)
+ = f .&. mask /= 0
+-}
+
+-- | Grab a register.
+grabReg :: RegNo -> FreeRegs -> FreeRegs
+grabReg r (FreeRegs g f d)
+
+ -- a general purpose reg
+ | r <= 31
+ , mask <- complement (1 `shiftL` fromIntegral r)
+ = FreeRegs (g .&. mask) f d
+
+ -- use the first 22 float regs as double precision
+ | r >= 32
+ , r <= 53
+ , mask <- complement (1 `shiftL` (fromIntegral r - 32))
+ = FreeRegs g f (d .&. mask)
+
+ -- use the last 10 float regs as single precision
+ | otherwise
+ , mask <- complement (1 `shiftL` (fromIntegral r - 32))
+ = FreeRegs g (f .&. mask) d
+
+
+
+-- | 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 :: RegNo -> FreeRegs -> FreeRegs
+releaseReg r regs@(FreeRegs g f d)
+
+ -- used by STG machine, or otherwise unavailable
+ | r >= 0 && r <= 15 = regs
+ | r >= 17 && r <= 21 = regs
+ | r >= 24 && r <= 31 = regs
+ | r >= 32 && r <= 41 = regs
+ | r >= 54 && r <= 59 = regs
+
+ -- never release the high part of double regs.
+ | r == 43 = regs
+ | r == 45 = regs
+ | r == 47 = regs
+ | r == 49 = regs
+ | r == 51 = regs
+ | r == 53 = regs
+
+ -- a general purpose reg
+ | r <= 31
+ , mask <- 1 `shiftL` fromIntegral r
+ = FreeRegs (g .|. mask) f d
+
+ -- use the first 22 float regs as double precision
+ | r >= 32
+ , r <= 53
+ , mask <- 1 `shiftL` (fromIntegral r - 32)
+ = FreeRegs g f (d .|. mask)
+
+ -- use the last 10 float regs as single precision
+ | otherwise
+ , mask <- 1 `shiftL` (fromIntegral r - 32)
+ = FreeRegs g (f .|. mask) d
+
+
+-- | Allocate a register in the map.
+allocateReg :: RegNo -> FreeRegs -> FreeRegs
+allocateReg r regs -- (FreeRegs g f d)
+
+ -- if the reg isn't actually free then we're in trouble
+{- | not $ regIsFree r regs
+ = pprPanic
+ "RegAllocLinear.allocateReg"
+ (text "reg " <> ppr r <> text " is not free")
+-}
+ | otherwise
+ = grabReg r regs
+
+
+
+--------------------------------------------------------------------------------
-- If we have less than 32 registers, or if we have efficient 64-bit words,
-- we will just use a single bitfield.
-#if defined(alpha_TARGET_ARCH)
-type FreeRegs = Word64
#else
+
+# if defined(alpha_TARGET_ARCH)
+type FreeRegs = Word64
+# else
type FreeRegs = Word32
-#endif
+# endif
noFreeRegs :: FreeRegs
noFreeRegs = 0
-- (a) save any temporaries which will be clobbered by this instruction
clobber_saves <- saveClobberedTemps real_written r_dying
- {-
- freeregs <- getFreeRegsR
+
+{- freeregs <- getFreeRegsR
assig <- getAssigR
- pprTrace "raInsn" (docToSDoc (pprInstr instr) $$ ppr r_dying <+> ppr w_dying $$ ppr virt_read <+> ppr virt_written $$ text (show freeregs) $$ ppr assig) $ do
- -}
+ pprTrace "raInsn"
+ (docToSDoc (pprInstr instr) $$ ppr r_dying <+> ppr w_dying $$ ppr virt_read <+> ppr virt_written
+ $$ text (show freeregs) $$ ppr assig)
+ $ do
+-}
-- (b), (c) allocate real regs for all regs read by this instruction.
(r_spills, r_allocd) <-
clobberRegs [] = return () -- common case
clobberRegs clobbered = do
freeregs <- getFreeRegsR
+-- setFreeRegsR $! foldr grabReg freeregs clobbered
setFreeRegsR $! foldr allocateReg freeregs clobbered
+
assig <- getAssigR
setAssigR $! clobber assig (ufmToList assig)
where
case getFreeRegs (regClass r) freeregs of
-- case (2): we have a free register
- my_reg:_ -> do
+ my_reg:_ -> {- pprTrace "alloc" (ppr r <+> ppr my_reg <+> ppr freeClass) $ -}
+ do
spills' <- loadTemp reading r loc my_reg spills
let new_loc
| Just (InMem slot) <- loc, reading = InBoth my_reg slot
| otherwise = InReg my_reg
setAssigR (addToUFM assig r $! new_loc)
- setFreeRegsR (allocateReg my_reg freeregs)
+ setFreeRegsR $ allocateReg my_reg freeregs
allocateRegsAndSpill reading keep spills' (my_reg:alloc) rs
-- case (3): we need to push something out to free up a register
let (temp_to_push_out, my_reg)
= case candidates2 of
- [] -> panic "RegAllocLinear.allocRegsAndSpill: no spill candidates"
+ [] -> panic $ "RegAllocLinear.allocRegsAndSpill: no spill candidates"
+ ++ "assignment: " ++ show (ufmToList assig) ++ "\n"
(x:_) -> x
(spill_insn, slot) <- spillR (RealReg my_reg) temp_to_push_out