diff options
Diffstat (limited to 'compiler/nativeGen/RegAlloc/Graph/SpillCost.hs')
| -rw-r--r-- | compiler/nativeGen/RegAlloc/Graph/SpillCost.hs | 51 |
1 files changed, 34 insertions, 17 deletions
diff --git a/compiler/nativeGen/RegAlloc/Graph/SpillCost.hs b/compiler/nativeGen/RegAlloc/Graph/SpillCost.hs index f603b609df..4d5f44a8d3 100644 --- a/compiler/nativeGen/RegAlloc/Graph/SpillCost.hs +++ b/compiler/nativeGen/RegAlloc/Graph/SpillCost.hs @@ -1,4 +1,4 @@ - +{-# LANGUAGE ScopedTypeVariables #-} module RegAlloc.Graph.SpillCost ( SpillCostRecord, plusSpillCostRecord, @@ -30,9 +30,11 @@ import Digraph (flattenSCCs) import Outputable import Platform import State +import CFG import Data.List (nub, minimumBy) import Data.Maybe +import Control.Monad (join) -- | Records the expected cost to spill some regster. @@ -47,6 +49,10 @@ type SpillCostRecord type SpillCostInfo = UniqFM SpillCostRecord +-- | Block membership in a loop +type LoopMember = Bool + +type SpillCostState = State (UniqFM SpillCostRecord) () -- | An empty map of spill costs. zeroSpillCostInfo :: SpillCostInfo @@ -71,12 +77,13 @@ plusSpillCostRecord (r1, a1, b1, c1) (r2, a2, b2, c2) -- For each vreg, the number of times it was written to, read from, -- and the number of instructions it was live on entry to (lifetime) -- -slurpSpillCostInfo :: (Outputable instr, Instruction instr) +slurpSpillCostInfo :: forall instr statics. (Outputable instr, Instruction instr) => Platform + -> Maybe CFG -> LiveCmmDecl statics instr -> SpillCostInfo -slurpSpillCostInfo platform cmm +slurpSpillCostInfo platform cfg cmm = execState (countCmm cmm) zeroSpillCostInfo where countCmm CmmData{} = return () @@ -90,35 +97,36 @@ slurpSpillCostInfo platform cmm | LiveInfo _ _ (Just blockLive) _ <- info , Just rsLiveEntry <- mapLookup blockId blockLive , rsLiveEntry_virt <- takeVirtuals rsLiveEntry - = countLIs rsLiveEntry_virt instrs + = countLIs (loopMember blockId) rsLiveEntry_virt instrs | otherwise = error "RegAlloc.SpillCost.slurpSpillCostInfo: bad block" - countLIs _ [] + countLIs :: LoopMember -> UniqSet VirtualReg -> [LiveInstr instr] -> SpillCostState + countLIs _ _ [] = return () -- Skip over comment and delta pseudo instrs. - countLIs rsLive (LiveInstr instr Nothing : lis) + countLIs inLoop rsLive (LiveInstr instr Nothing : lis) | isMetaInstr instr - = countLIs rsLive lis + = countLIs inLoop rsLive lis | otherwise = pprPanic "RegSpillCost.slurpSpillCostInfo" $ text "no liveness information on instruction " <> ppr instr - countLIs rsLiveEntry (LiveInstr instr (Just live) : lis) + countLIs inLoop rsLiveEntry (LiveInstr instr (Just live) : lis) = do -- Increment the lifetime counts for regs live on entry to this instr. - mapM_ incLifetime $ nonDetEltsUniqSet rsLiveEntry + mapM_ (incLifetime (loopCount inLoop)) $ nonDetEltsUniqSet rsLiveEntry -- This is non-deterministic but we do not -- currently support deterministic code-generation. -- See Note [Unique Determinism and code generation] -- Increment counts for what regs were read/written from. let (RU read written) = regUsageOfInstr platform instr - mapM_ incUses $ catMaybes $ map takeVirtualReg $ nub read - mapM_ incDefs $ catMaybes $ map takeVirtualReg $ nub written + mapM_ (incUses (loopCount inLoop)) $ catMaybes $ map takeVirtualReg $ nub read + mapM_ (incDefs (loopCount inLoop)) $ catMaybes $ map takeVirtualReg $ nub written -- Compute liveness for entry to next instruction. let liveDieRead_virt = takeVirtuals (liveDieRead live) @@ -132,12 +140,21 @@ slurpSpillCostInfo platform cmm = (rsLiveAcross `unionUniqSets` liveBorn_virt) `minusUniqSet` liveDieWrite_virt - countLIs rsLiveNext lis - - incDefs reg = modify $ \s -> addToUFM_C plusSpillCostRecord s reg (reg, 1, 0, 0) - incUses reg = modify $ \s -> addToUFM_C plusSpillCostRecord s reg (reg, 0, 1, 0) - incLifetime reg = modify $ \s -> addToUFM_C plusSpillCostRecord s reg (reg, 0, 0, 1) - + countLIs inLoop rsLiveNext lis + + loopCount inLoop + | inLoop = 10 + | otherwise = 1 + incDefs count reg = modify $ \s -> addToUFM_C plusSpillCostRecord s reg (reg, count, 0, 0) + incUses count reg = modify $ \s -> addToUFM_C plusSpillCostRecord s reg (reg, 0, count, 0) + incLifetime count reg = modify $ \s -> addToUFM_C plusSpillCostRecord s reg (reg, 0, 0, count) + + loopBlocks = CFG.loopMembers <$> cfg + loopMember bid + | Just isMember <- join (mapLookup bid <$> loopBlocks) + = isMember + | otherwise + = False -- | Take all the virtual registers from this set. takeVirtuals :: UniqSet Reg -> UniqSet VirtualReg |