Repository : ssh://darcs.haskell.org//srv/darcs/ghc On branch :
http://hackage.haskell.org/trac/ghc/changeset/167fed1eab77bdcf932fd7439b1ac7a01f5d6eb0 >--------------------------------------------------------------- commit 167fed1eab77bdcf932fd7439b1ac7a01f5d6eb0 Author: Max Bolingbroke <batterseapo...@hotmail.com> Date: Tue Jan 3 13:53:45 2012 +0000 Ensure we localise AbsVars when building binding sites >--------------------------------------------------------------- .../supercompile/Supercompile/Drive/Process.hs | 18 +++++++++++++++--- 1 files changed, 15 insertions(+), 3 deletions(-) diff --git a/compiler/supercompile/Supercompile/Drive/Process.hs b/compiler/supercompile/Supercompile/Drive/Process.hs index ef9a318..af20b89 100644 --- a/compiler/supercompile/Supercompile/Drive/Process.hs +++ b/compiler/supercompile/Supercompile/Drive/Process.hs @@ -45,7 +45,7 @@ import Supercompile.Utilities hiding (Monad(..)) import Name (getOccString) import Var (isId, isTyVar, varType, setVarType) -import Id (idType, idOccInfo, zapFragileIdInfo, setIdOccInfo) +import Id (idType, idOccInfo, zapFragileIdInfo, setIdOccInfo, localiseId) import Type (isUnLiftedType, mkTyVarTy) import Coercion (isCoVar, mkCoVarCo, mkUnsafeCo, coVarKind_maybe, mkCoercionType) import TyCon (PrimRep(..)) @@ -455,8 +455,20 @@ renameAbsVar rn (AbsVar { absVarDead = dead, absVarVar = x }) -- 1. If the h-function is unlifted, this delays its evaluation (so its effects, if any, do not happen too early) -- 2. This expresses to GHC that we don't necessarily want the work in h-functions to be shared +-- NB: it's important that we use localiseId on the absVarVar at binding sites, or else if we start +-- with a state where a global Id is lambda-bound (because there is no unfolding) we might end up having an h-function +-- that is lambda-abstracted over a global Id, which causes the assembler to barf. +-- +-- (We will rely on a later simplifier run to propagate the local Id bindings down to the possibly-global Id use sites) +-- +-- This will rarely happpen in practice because global variables should be Let-bound in the heap, which would prevent +-- us from lambda-abstracting over them. However, it can happen if the global is abstracted due to generalisation, +-- such as when the let-bound thing binds a (:) and we generalise away some other (:). +absVarBinder :: AbsVar -> Var +absVarBinder = localiseId . absVarVar + absVarLambdas :: Symantics ann => [AbsVar] -> ann (TermF ann) -> ann (TermF ann) -absVarLambdas xs = tyVarIdLambdas (map absVarVar xs) +absVarLambdas xs = tyVarIdLambdas (map absVarBinder xs) applyAbsVars :: Symantics ann => Var -> [AbsVar] -> ann (TermF ann) applyAbsVars x xs = snd (foldl go (unitVarSet x, var x) xs) @@ -499,7 +511,7 @@ applyAbsVars x xs = snd (foldl go (unitVarSet x, var x) xs) -- Unlifted thing of PtrRep: yes, this can really happen (ByteArray# etc) PtrRep -> pprPanic "applyAbsVars: dead unlifted variable with PrimRep PtrRep: FIXME" (ppr ty) -> let_ x (e_repr `cast` mkUnsafeCo e_repr_ty ty) (e `app` x)) - where shadowy_x = absVarVar absx + where shadowy_x = absVarBinder absx x = uniqAway (mkInScopeSet fvs) shadowy_x ty = idType x False -> (fvs `extendVarSet` x, case () of _______________________________________________ Cvs-ghc mailing list Cvs-ghc@haskell.org http://www.haskell.org/mailman/listinfo/cvs-ghc
