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    1 module GHC.CmmToAsm.Reg.Linear.Stats (
    2         binSpillReasons,
    3         countRegRegMovesNat,
    4         pprStats
    5 )
    6 
    7 where
    8 
    9 import GHC.Prelude
   10 
   11 import GHC.CmmToAsm.Reg.Linear.Base
   12 import GHC.CmmToAsm.Reg.Liveness
   13 import GHC.CmmToAsm.Instr
   14 import GHC.Types.Unique (Unique)
   15 import GHC.CmmToAsm.Types
   16 
   17 import GHC.Types.Unique.FM
   18 
   19 import GHC.Utils.Outputable
   20 import GHC.Utils.Monad.State.Strict
   21 
   22 -- | Build a map of how many times each reg was alloced, clobbered, loaded etc.
   23 binSpillReasons
   24         :: [SpillReason] -> UniqFM Unique [Int]
   25         -- See Note [UniqFM and the register allocator]
   26 binSpillReasons reasons
   27         = addListToUFM_C
   28                 (zipWith (+))
   29                 emptyUFM
   30                 (map (\reason -> case reason of
   31                         SpillAlloc r    -> (r, [1, 0, 0, 0, 0])
   32                         SpillClobber r  -> (r, [0, 1, 0, 0, 0])
   33                         SpillLoad r     -> (r, [0, 0, 1, 0, 0])
   34                         SpillJoinRR r   -> (r, [0, 0, 0, 1, 0])
   35                         SpillJoinRM r   -> (r, [0, 0, 0, 0, 1])) reasons)
   36 
   37 
   38 -- | Count reg-reg moves remaining in this code.
   39 countRegRegMovesNat
   40         :: Instruction instr
   41         => NatCmmDecl statics instr -> Int
   42 
   43 countRegRegMovesNat cmm
   44         = execState (mapGenBlockTopM countBlock cmm) 0
   45  where
   46         countBlock b@(BasicBlock _ instrs)
   47          = do   mapM_ countInstr instrs
   48                 return  b
   49 
   50         countInstr instr
   51                 | Just _        <- takeRegRegMoveInstr instr
   52                 = do    modify (+ 1)
   53                         return instr
   54 
   55                 | otherwise
   56                 =       return instr
   57 
   58 
   59 -- | Pretty print some RegAllocStats
   60 pprStats
   61         :: Instruction instr
   62         => [NatCmmDecl statics instr] -> [RegAllocStats] -> SDoc
   63 
   64 pprStats code statss
   65  = let  -- sum up all the instrs inserted by the spiller
   66         -- See Note [UniqFM and the register allocator]
   67         spills :: UniqFM Unique [Int]
   68         spills          = foldl' (plusUFM_C (zipWith (+)))
   69                                 emptyUFM
   70                         $ map ra_spillInstrs statss
   71 
   72         spillTotals     = foldl' (zipWith (+))
   73                                 [0, 0, 0, 0, 0]
   74                         $ nonDetEltsUFM spills
   75                         -- See Note [Unique Determinism and code generation]
   76 
   77         -- count how many reg-reg-moves remain in the code
   78         moves           = sum $ map countRegRegMovesNat code
   79 
   80         pprSpill (reg, spills)
   81                 = parens $ (hcat $ punctuate (text ", ")  (doubleQuotes (ppr reg) : map ppr spills))
   82 
   83    in   (  text "-- spills-added-total"
   84         $$ text "--    (allocs, clobbers, loads, joinRR, joinRM, reg_reg_moves_remaining)"
   85         $$ (parens $ (hcat $ punctuate (text ", ") (map ppr spillTotals ++ [ppr moves])))
   86         $$ text ""
   87         $$ text "-- spills-added"
   88         $$ text "--    (reg_name, allocs, clobbers, loads, joinRR, joinRM)"
   89         $$ (pprUFMWithKeys spills (vcat . map pprSpill))
   90         $$ text "")
   91