Repository : ssh://darcs.haskell.org//srv/darcs/ghc On branch : master
http://hackage.haskell.org/trac/ghc/changeset/c588395719241c4b5756bd8d60dbf822915dfc5b >--------------------------------------------------------------- commit c588395719241c4b5756bd8d60dbf822915dfc5b Author: Simon Marlow <marlo...@gmail.com> Date: Thu Oct 25 16:18:36 2012 +0100 Fix a bug in CmmSink exposed by a recent optimisation (#7366) >--------------------------------------------------------------- compiler/cmm/CmmSink.hs | 10 ++++++++++ 1 files changed, 10 insertions(+), 0 deletions(-) diff --git a/compiler/cmm/CmmSink.hs b/compiler/cmm/CmmSink.hs index 9565fec..7553e37 100644 --- a/compiler/cmm/CmmSink.hs +++ b/compiler/cmm/CmmSink.hs @@ -384,6 +384,7 @@ tryToInline dflags live node assigs = go usages node [] assigs -- usages of the regs on the RHS to 2. cannot_inline = skipped `regsUsedIn` rhs -- Note [dependent assignments] + || l `elem` skipped || not (okToInline dflags rhs node) occurs_once = not (l `elemRegSet` live) @@ -415,6 +416,15 @@ tryToInline dflags live node assigs = go usages node [] assigs -- -- For now we do nothing, because this would require putting -- everything inside UniqSM. +-- +-- One more variant of this (#7366): +-- +-- [ y = e, y = z ] +-- +-- If we don't want to inline y = e, because y is used many times, we +-- might still be tempted to inline y = z (because we always inline +-- trivial rhs's). But of course we can't, because y is equal to e, +-- not z. addUsage :: UniqFM Int -> LocalReg -> UniqFM Int addUsage m r = addToUFM_C (+) m r 1 _______________________________________________ Cvs-ghc mailing list Cvs-ghc@haskell.org http://www.haskell.org/mailman/listinfo/cvs-ghc
