-- | Graph coloring register allocator.
--
-- TODO:
--- Live range splitting:
--- At the moment regs that are spilled are spilled for all time, even though
--- we might be able to allocate them a hardreg in different parts of the code.
---
--- As we're aggressively coalescing before register allocation proper we're not currently
--- using the coalescence information present in the graph.
---
-- The function that choosing the potential spills could be a bit cleverer.
---
-- Colors in graphviz graphs could be nicer.
--
+{-# OPTIONS -fno-warn-missing-signatures #-}
module RegAllocColor (
regAlloc,
import RegAllocStats
import MachRegs
import MachInstrs
-import RegCoalesce
import PprMach
import UniqSupply
regAlloc dump regsFree slotsFree code
= do
- (code_final, debug_codeGraphs, graph_final)
+ (code_final, debug_codeGraphs, _)
<- regAlloc_spin dump 0 trivColorable regsFree slotsFree [] code
return ( code_final
$$ text "slotsFree = " <> ppr (sizeUniqSet slotsFree))
-- build a conflict graph from the code.
- graph <- buildGraph code
+ graph <- {-# SCC "BuildGraph" #-} buildGraph code
+
+ -- VERY IMPORTANT:
+ -- We really do want the graph to be fully evaluated _before_ we start coloring.
+ -- If we don't do this now then when the call to Color.colorGraph forces bits of it,
+ -- the heap will be filled with half evaluated pieces of graph and zillions of apply thunks.
+ --
+ seqGraph graph `seq` return ()
+
-- build a map of how many instructions each reg lives for.
-- this is lazy, it won't be computed unless we need to spill
- let fmLife = plusUFMs_C (\(r1, l1) (r2, l2) -> (r1, l1 + l2))
+
+ let fmLife = {-# SCC "LifetimeCount" #-} plusUFMs_C (\(r1, l1) (_, l2) -> (r1, l1 + l2))
$ map lifetimeCount code
-- record startup state
let spill = chooseSpill_maxLife fmLife
-- try and color the graph
- let (graph_colored, rsSpill)
- = Color.colorGraph regsFree triv spill graph
+ let (graph_colored, rsSpill, rmCoalesce)
+ = {-# SCC "ColorGraph" #-} Color.colorGraph regsFree triv spill graph
+
+ -- rewrite regs in the code that have been coalesced
+ let patchF reg = case lookupUFM rmCoalesce reg of
+ Just reg' -> reg'
+ Nothing -> reg
+ let code_coalesced
+ = map (patchEraseLive patchF) code
+
-- see if we've found a coloring
if isEmptyUniqSet rsSpill
then do
-- patch the registers using the info in the graph
- let code_patched = map (patchRegsFromGraph graph_colored) code
+ let code_patched = map (patchRegsFromGraph graph_colored) code_coalesced
-- clean out unneeded SPILL/RELOADs
let code_spillclean = map cleanSpills code_patched
-- strip off liveness information
let code_nat = map stripLive code_patched
- -- rewrite SPILL/REALOAD pseudos into real instructions
+ -- rewrite SPILL/RELOAD pseudos into real instructions
let spillNatTop = mapGenBlockTop spillNatBlock
let code_final = map spillNatTop code_nat
let stat =
RegAllocStatsColored
{ raGraph = graph_colored
+ , raCoalesced = rmCoalesce
, raPatched = code_patched
, raSpillClean = code_spillclean
, raFinal = code_final
- , raSRMs = foldl addSRM (0, 0, 0) $ map countSRMs code_spillclean }
+ , raSRMs = foldl' addSRM (0, 0, 0) $ map countSRMs code_spillclean }
- return ( code_final
- , if dump
- then [stat] ++ maybeToList stat1 ++ debug_codeGraphs
+
+ let statList =
+ if dump then [stat] ++ maybeToList stat1 ++ debug_codeGraphs
else []
+
+ -- space leak avoidance
+ seqList statList `seq` return ()
+
+ return ( code_final
+ , statList
, graph_colored)
else do
-- spill the uncolored regs
(code_spilled, slotsFree', spillStats)
- <- regSpill code slotsFree rsSpill
-
+ <- regSpill code_coalesced slotsFree rsSpill
+
-- recalculate liveness
let code_nat = map stripLive code_spilled
code_relive <- mapM regLiveness code_nat
let stat =
RegAllocStatsSpill
{ raGraph = graph_colored
+ , raCoalesced = rmCoalesce
, raSpillStats = spillStats
, raLifetimes = fmLife
, raSpilled = code_spilled }
- -- try again
- regAlloc_spin dump (spinCount + 1) triv regsFree slotsFree'
- (if dump
+ let statList =
+ if dump
then [stat] ++ maybeToList stat1 ++ debug_codeGraphs
- else [])
+ else []
+
+ -- space leak avoidance
+ seqList statList `seq` return ()
+
+ regAlloc_spin dump (spinCount + 1) triv regsFree slotsFree'
+ statList
code_relive
buildGraph code
= do
- -- Add the reg-reg conflicts to the graph
- let conflictSets = unionManyBags (map slurpConflicts code)
- let graph_conflict = foldrBag graphAddConflictSet Color.initGraph conflictSets
+ -- Slurp out the conflicts and reg->reg moves from this code
+ let (conflictList, moveList) =
+ unzip $ map slurpConflicts code
+ let conflictBag = unionManyBags conflictList
+ let moveBag = unionManyBags moveList
+
+ -- Add the reg-reg conflicts to the graph
+ let graph_conflict = foldrBag graphAddConflictSet Color.initGraph conflictBag
-- Add the coalescences edges to the graph.
- let coalesce = unionManyBags (map slurpJoinMovs code)
- let graph_coalesce = foldrBag graphAddCoalesce graph_conflict coalesce
+ let graph_coalesce = foldrBag graphAddCoalesce graph_conflict moveBag
- return $ graph_coalesce
+ return graph_coalesce
-- | Add some conflict edges to the graph.
-> Color.Graph Reg RegClass Reg
graphAddCoalesce (r1, r2) graph
- | RealReg regno <- r1
+ | RealReg _ <- r1
= Color.addPreference (regWithClass r2) r1 graph
- | RealReg regno <- r2
+ | RealReg _ <- r2
= Color.addPreference (regWithClass r1) r2 graph
| otherwise
= pprPanic "patchRegsFromGraph: register mapping failed."
( text "There is no node in the graph for register " <> ppr reg
$$ ppr code
- $$ Color.dotGraph (\x -> text "white") trivColorable graph)
+ $$ Color.dotGraph (\_ -> text "white") trivColorable graph)
in patchEraseLive patchF code
plusUFMs_C :: (elt -> elt -> elt) -> [UniqFM elt] -> UniqFM elt
plusUFMs_C f maps
- = foldl (plusUFM_C f) emptyUFM maps
-
+ = foldl' (plusUFM_C f) emptyUFM maps
+
+
+-----
+-- for when laziness just isn't what you wanted...
+--
+seqGraph :: Color.Graph Reg RegClass Reg -> ()
+seqGraph graph = seqNodes (eltsUFM (Color.graphMap graph))
+
+seqNodes :: [Color.Node Reg RegClass Reg] -> ()
+seqNodes ns
+ = case ns of
+ [] -> ()
+ (n : ns) -> seqNode n `seq` seqNodes ns
+
+seqNode :: Color.Node Reg RegClass Reg -> ()
+seqNode node
+ = seqReg (Color.nodeId node)
+ `seq` seqRegClass (Color.nodeClass node)
+ `seq` seqMaybeReg (Color.nodeColor node)
+ `seq` (seqRegList (uniqSetToList (Color.nodeConflicts node)))
+ `seq` (seqRegList (uniqSetToList (Color.nodeExclusions node)))
+ `seq` (seqRegList (Color.nodePreference node))
+ `seq` (seqRegList (uniqSetToList (Color.nodeCoalesce node)))
+
+seqReg :: Reg -> ()
+seqReg reg
+ = case reg of
+ RealReg _ -> ()
+ VirtualRegI _ -> ()
+ VirtualRegHi _ -> ()
+ VirtualRegF _ -> ()
+ VirtualRegD _ -> ()
+
+seqRegClass :: RegClass -> ()
+seqRegClass c
+ = case c of
+ RcInteger -> ()
+ RcFloat -> ()
+ RcDouble -> ()
+
+seqMaybeReg :: Maybe Reg -> ()
+seqMaybeReg mr
+ = case mr of
+ Nothing -> ()
+ Just r -> seqReg r
+
+seqRegList :: [Reg] -> ()
+seqRegList rs
+ = case rs of
+ [] -> ()
+ (r : rs) -> seqReg r `seq` seqRegList rs
+
+seqList :: [a] -> ()
+seqList ls
+ = case ls of
+ [] -> ()
+ (r : rs) -> r `seq` seqList rs
+
+
projects / ghc-hetmet.git / blobdiff