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| author | Simon Marlow <marlowsd@gmail.com> | 2012-09-21 11:05:53 +0100 |
|---|---|---|
| committer | Simon Marlow <marlowsd@gmail.com> | 2012-09-24 09:51:58 +0100 |
| commit | acdebbbad25f6d9c5c11550cc8998db10b8b8a48 (patch) | |
| tree | d5f422757b96192383cf1b189bbe6b42e15f56d2 /compiler/cmm/CmmSink.hs | |
| parent | 0b79d5cd4687dacf7efd430df7fba9d9a5a5ce32 (diff) | |
| download | haskell-acdebbbad25f6d9c5c11550cc8998db10b8b8a48.tar.gz | |
no functional changes
Diffstat (limited to 'compiler/cmm/CmmSink.hs')
| -rw-r--r-- | compiler/cmm/CmmSink.hs | 23 |
1 files changed, 16 insertions, 7 deletions
diff --git a/compiler/cmm/CmmSink.hs b/compiler/cmm/CmmSink.hs index 8c5c99d469..28e3b7723d 100644 --- a/compiler/cmm/CmmSink.hs +++ b/compiler/cmm/CmmSink.hs @@ -155,7 +155,7 @@ cmmSink dflags graph = ofBlockList (g_entry graph) $ sink mapEmpty $ blocks drop_if a@(r,rhs,_) live_sets = (should_drop, live_sets') where should_drop = conflicts dflags a final_last - || {- not (isTiny rhs) && -} live_in_multi live_sets r + || {- not (isSmall rhs) && -} live_in_multi live_sets r || r `Set.member` live_in_joins live_sets' | should_drop = live_sets @@ -172,12 +172,21 @@ cmmSink dflags graph = ofBlockList (g_entry graph) $ sink mapEmpty $ blocks mapFromList [ (l, filterAssignments dflags (getLive l) assigs'') | l <- succs ] -{- --- tiny: an expression we don't mind duplicating -isTiny :: CmmExpr -> Bool -isTiny (CmmReg _) = True -isTiny (CmmLit _) = True -isTiny _other = False +{- TODO: enable this later, when we have some good tests in place to + measure the effect and tune it. + +-- small: an expression we don't mind duplicating +isSmall :: CmmExpr -> Bool +isSmall (CmmReg (CmmLocal _)) = True -- not globals, we want to coalesce them instead +isSmall (CmmLit _) = True +isSmall (CmmMachOp (MO_Add _) [x,y]) = isTrivial x && isTrivial y +isSmall (CmmRegOff (CmmLocal _) _) = True +isSmall _ = False + +isTrivial :: CmmExpr -> Bool +isTrivial (CmmReg (CmmLocal _)) = True +isTrivial (CmmLit _) = True +isTrivial _ = False -} -- |