import CostCentre
import Module
import Id
+import Name ( localiseName )
import MkId ( seqId )
import Var ( Var, TyVar, tyVarKind )
import IdInfo ( vanillaIdInfo )
import MonadUtils
import Control.Monad
-import Data.List
\end{code}
%************************************************************************
; sel_binds <- mkSelectorBinds pat body_expr
; return (sel_binds ++ rest) }
-{- Note [Rules and inlining]
- ~~~~~~~~~~~~~~~~~~~~~~~~~
- Common special case: no type or dictionary abstraction
- This is a bit less trivial than you might suppose
- The naive way woudl be to desguar to something like
- f_lcl = ...f_lcl... -- The "binds" from AbsBinds
- M.f = f_lcl -- Generated from "exports"
- But we don't want that, because if M.f isn't exported,
- it'll be inlined unconditionally at every call site (its rhs is
- trivial). That would be ok unless it has RULES, which would
- thereby be completely lost. Bad, bad, bad.
-
- Instead we want to generate
- M.f = ...f_lcl...
- f_lcl = M.f
- Now all is cool. The RULES are attached to M.f (by SimplCore),
- and f_lcl is rapidly inlined away.
-
- This does not happen in the same way to polymorphic binds,
- because they desugar to
- M.f = /\a. let f_lcl = ...f_lcl... in f_lcl
- Although I'm a bit worried about whether full laziness might
- float the f_lcl binding out and then inline M.f at its call site -}
-
dsHsBind auto_scc rest (AbsBinds [] [] exports binds)
= do { core_prs <- ds_lhs_binds NoSccs binds
; let env = mkABEnv exports
- ar_env = mkArityEnv binds
do_one (lcl_id, rhs)
| Just (_, gbl_id, _, spec_prags) <- lookupVarEnv env lcl_id
- = WARN( not (null spec_prags), ppr gbl_id $$ ppr spec_prags ) -- Not overloaded
- makeCorePair gbl_id (lookupArity ar_env lcl_id)
- (addAutoScc auto_scc gbl_id rhs)
+ = do { let rhs' = addAutoScc auto_scc gbl_id rhs
+ ; (spec_binds, rules) <- dsSpecs gbl_id (Let (Rec core_prs) rhs') spec_prags
+ -- See Note [Specialising in no-dict case]
+ ; let gbl_id' = addIdSpecialisations gbl_id rules
+ main_bind = makeCorePair gbl_id' False 0 rhs'
+ ; return (main_bind : spec_binds) }
- | otherwise = (lcl_id, rhs)
+ | otherwise = return [(lcl_id, rhs)]
locals' = [(lcl_id, Var gbl_id) | (_, gbl_id, lcl_id, _) <- exports]
-- Note [Rules and inlining]
- ; return (map do_one core_prs ++ locals' ++ rest) }
+ ; export_binds <- mapM do_one core_prs
+ ; return (concat export_binds ++ locals' ++ rest) }
-- No Rec needed here (contrast the other AbsBinds cases)
-- because we can rely on the enclosing dsBind to wrap in Rec
-{- Note [Abstracting over tyvars only]
- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
- When abstracting over type variable only (not dictionaries), we don't really need to
- built a tuple and select from it, as we do in the general case. Instead we can take
-
- AbsBinds [a,b] [ ([a,b], fg, fl, _),
- ([b], gg, gl, _) ]
- { fl = e1
- gl = e2
- h = e3 }
-
- and desugar it to
-
- fg = /\ab. let B in e1
- gg = /\b. let a = () in let B in S(e2)
- h = /\ab. let B in e3
-
- where B is the *non-recursive* binding
- fl = fg a b
- gl = gg b
- h = h a b -- See (b); note shadowing!
-
- Notice (a) g has a different number of type variables to f, so we must
- use the mkArbitraryType thing to fill in the gaps.
- We use a type-let to do that.
-
- (b) The local variable h isn't in the exports, and rather than
- clone a fresh copy we simply replace h by (h a b), where
- the two h's have different types! Shadowing happens here,
- which looks confusing but works fine.
-
- (c) The result is *still* quadratic-sized if there are a lot of
- small bindings. So if there are more than some small
- number (10), we filter the binding set B by the free
- variables of the particular RHS. Tiresome.
-
- Why got to this trouble? It's a common case, and it removes the
- quadratic-sized tuple desugaring. Less clutter, hopefullly faster
- compilation, especially in a case where there are a *lot* of
- bindings.
--}
-
-
dsHsBind auto_scc rest (AbsBinds tyvars [] exports binds)
| opt_DsMultiTyVar -- This (static) debug flag just lets us
-- switch on and off this optimisation to
where
fvs = exprSomeFreeVars (`elemVarSet` bndrs) rhs
- ar_env = mkArityEnv binds
env = mkABEnv exports
-
mk_lg_bind lcl_id gbl_id tyvars
= NonRec (setIdInfo lcl_id vanillaIdInfo)
-- Nuke the IdInfo so that no old unfoldings
do_one lg_binds (lcl_id, rhs)
| Just (id_tvs, gbl_id, _, spec_prags) <- lookupVarEnv env lcl_id
- = WARN( not (null spec_prags), ppr gbl_id $$ ppr spec_prags ) -- Not overloaded
- (let rhs' = addAutoScc auto_scc gbl_id $
- mkLams id_tvs $
- mkLets [ NonRec tv (Type (lookupVarEnv_NF arby_env tv))
- | tv <- tyvars, not (tv `elem` id_tvs)] $
- add_lets lg_binds rhs
- in return (mk_lg_bind lcl_id gbl_id id_tvs,
- makeCorePair gbl_id (lookupArity ar_env lcl_id) rhs'))
+ = do { let rhs' = addAutoScc auto_scc gbl_id $
+ mkLams id_tvs $
+ mkLets [ NonRec tv (Type (lookupVarEnv_NF arby_env tv))
+ | tv <- tyvars, not (tv `elem` id_tvs)] $
+ add_lets lg_binds rhs
+ ; (spec_binds, rules) <- dsSpecs gbl_id rhs' spec_prags
+ ; let gbl_id' = addIdSpecialisations gbl_id rules
+ main_bind = makeCorePair gbl_id' False 0 rhs'
+ ; return (mk_lg_bind lcl_id gbl_id' id_tvs, main_bind : spec_binds) }
| otherwise
= do { non_exp_gbl_id <- newUniqueId lcl_id (mkForAllTys tyvars (idType lcl_id))
; return (mk_lg_bind lcl_id non_exp_gbl_id tyvars,
- (non_exp_gbl_id, mkLams tyvars (add_lets lg_binds rhs))) }
+ [(non_exp_gbl_id, mkLams tyvars (add_lets lg_binds rhs))]) }
; (_, core_prs') <- fixDs (\ ~(lg_binds, _) -> mapAndUnzipM (do_one lg_binds) core_prs)
- ; return (core_prs' ++ rest) }
+ ; return (concat core_prs' ++ rest) }
-- Another common case: one exported variable
-- Non-recursive bindings come through this way
= ASSERT( all (`elem` tyvars) all_tyvars )
do { core_prs <- ds_lhs_binds NoSccs binds
- ; let -- Always treat the binds as recursive, because the typechecker
- -- makes rather mixed-up dictionary bindings
+ ; let -- Always treat the binds as recursive, because the
+ -- typechecker makes rather mixed-up dictionary bindings
core_bind = Rec core_prs
- inl_arity = lookupArity (mkArityEnv binds) local
+ rhs = addAutoScc auto_scc global $
+ mkLams tyvars $ mkLams dicts $ Let core_bind (Var local)
- ; (spec_binds, rules) <- dsSpecs all_tyvars dicts tyvars global
- local inl_arity core_bind prags
+ ; (spec_binds, rules) <- dsSpecs global rhs prags
; let global' = addIdSpecialisations global rules
- rhs = addAutoScc auto_scc global $
- mkLams tyvars $ mkLams dicts $ Let core_bind (Var local)
- main_bind = makeCorePair global' (inl_arity + dictArity dicts) rhs
+ main_bind = makeCorePair global' (isDefaultMethod prags)
+ (dictArity dicts) rhs
; return (main_bind : spec_binds ++ rest) }
dsHsBind auto_scc rest (AbsBinds all_tyvars dicts exports binds)
= do { core_prs <- ds_lhs_binds NoSccs binds
; let env = mkABEnv exports
- ar_env = mkArityEnv binds
do_one (lcl_id,rhs) | Just (_, gbl_id, _, _prags) <- lookupVarEnv env lcl_id
= (lcl_id, addAutoScc auto_scc gbl_id rhs)
| otherwise = (lcl_id,rhs)
-- Rec because of mixed-up dictionary bindings
core_bind = Rec (map do_one core_prs)
- tup_expr = mkBigCoreVarTup locals
- tup_ty = exprType tup_expr
- poly_tup_expr = mkLams all_tyvars $ mkLams dicts $
- Let core_bind tup_expr
- locals = [local | (_, _, local, _) <- exports]
- local_tys = map idType locals
+ tup_expr = mkBigCoreVarTup locals
+ tup_ty = exprType tup_expr
+ poly_tup_rhs = mkLams all_tyvars $ mkLams dicts $
+ Let core_bind tup_expr
+ locals = [local | (_, _, local, _) <- exports]
+ local_tys = map idType locals
- ; poly_tup_id <- newSysLocalDs (exprType poly_tup_expr)
+ ; poly_tup_id <- newSysLocalDs (exprType poly_tup_rhs)
- ; let mk_bind ((tyvars, global, local, spec_prags), n) -- locals!!n == local
+ ; let mk_bind ((tyvars, global, _, spec_prags), n) -- locals!!n == local
= -- Need to make fresh locals to bind in the selector,
-- because some of the tyvars will be bound to 'Any'
do { let ty_args = map mk_ty_arg all_tyvars
substitute = substTyWith all_tyvars ty_args
; locals' <- newSysLocalsDs (map substitute local_tys)
; tup_id <- newSysLocalDs (substitute tup_ty)
- ; (spec_binds, rules) <- dsSpecs all_tyvars dicts tyvars global local
- (lookupArity ar_env local) core_bind
- spec_prags
- ; let global' = addIdSpecialisations global rules
- rhs = mkLams tyvars $ mkLams dicts $
+ ; let rhs = mkLams tyvars $ mkLams dicts $
mkTupleSelector locals' (locals' !! n) tup_id $
mkVarApps (mkTyApps (Var poly_tup_id) ty_args)
dicts
+ ; (spec_binds, rules) <- dsSpecs global
+ (Let (NonRec poly_tup_id poly_tup_rhs) rhs)
+ spec_prags
+ ; let global' = addIdSpecialisations global rules
; return ((global', rhs) : spec_binds) }
where
mk_ty_arg all_tyvar
; export_binds_s <- mapM mk_bind (exports `zip` [0..])
-- Don't scc (auto-)annotate the tuple itself.
- ; return ((poly_tup_id, poly_tup_expr) :
+ ; return ((poly_tup_id, poly_tup_rhs) :
(concat export_binds_s ++ rest)) }
------------------------
-makeCorePair :: Id-> Arity -> CoreExpr -> (Id, CoreExpr)
-makeCorePair gbl_id arity rhs
- | isInlinePragma (idInlinePragma gbl_id)
+makeCorePair :: Id -> Bool -> Arity -> CoreExpr -> (Id, CoreExpr)
+makeCorePair gbl_id is_default_method dict_arity rhs
+ | is_default_method -- Default methods are *always* inlined
+ = (gbl_id `setIdUnfolding` mkCompulsoryUnfolding rhs, rhs)
+
+ | not (isInlinePragma inline_prag)
+ = (gbl_id, rhs)
+
+ | Just arity <- inlinePragmaSat inline_prag
-- Add an Unfolding for an INLINE (but not for NOINLINE)
-- And eta-expand the RHS; see Note [Eta-expanding INLINE things]
- = (gbl_id `setIdUnfolding` mkInlineRule InlSat rhs arity,
- etaExpand arity rhs)
+ , let real_arity = dict_arity + arity
+ -- NB: The arity in the InlineRule takes account of the dictionaries
+ = (gbl_id `setIdUnfolding` mkInlineRule rhs (Just real_arity),
+ etaExpand real_arity rhs)
+
| otherwise
- = (gbl_id, rhs)
+ = (gbl_id `setIdUnfolding` mkInlineRule rhs Nothing, rhs)
+ where
+ inline_prag = idInlinePragma gbl_id
+
+dictArity :: [Var] -> Arity
+-- Don't count coercion variables in arity
+dictArity dicts = count isId dicts
+
------------------------
-type AbsBindEnv = VarEnv ([TyVar], Id, Id, [LSpecPrag])
+type AbsBindEnv = VarEnv ([TyVar], Id, Id, TcSpecPrags)
-- Maps the "lcl_id" for an AbsBind to
-- its "gbl_id" and associated pragmas, if any
-mkABEnv :: [([TyVar], Id, Id, [LSpecPrag])] -> AbsBindEnv
+mkABEnv :: [([TyVar], Id, Id, TcSpecPrags)] -> AbsBindEnv
-- Takes the exports of a AbsBinds, and returns a mapping
-- lcl_id -> (tyvars, gbl_id, lcl_id, prags)
mkABEnv exports = mkVarEnv [ (lcl_id, export) | export@(_, _, lcl_id, _) <- exports]
+\end{code}
-mkArityEnv :: LHsBinds Id -> IdEnv Arity
- -- Maps a local to the arity of its definition
-mkArityEnv binds = foldrBag (plusVarEnv . lhsBindArity) emptyVarEnv binds
+Note [Rules and inlining]
+~~~~~~~~~~~~~~~~~~~~~~~~~
+Common special case: no type or dictionary abstraction
+This is a bit less trivial than you might suppose
+The naive way woudl be to desguar to something like
+ f_lcl = ...f_lcl... -- The "binds" from AbsBinds
+ M.f = f_lcl -- Generated from "exports"
+But we don't want that, because if M.f isn't exported,
+it'll be inlined unconditionally at every call site (its rhs is
+trivial). That would be ok unless it has RULES, which would
+thereby be completely lost. Bad, bad, bad.
+
+Instead we want to generate
+ M.f = ...f_lcl...
+ f_lcl = M.f
+Now all is cool. The RULES are attached to M.f (by SimplCore),
+and f_lcl is rapidly inlined away.
+
+This does not happen in the same way to polymorphic binds,
+because they desugar to
+ M.f = /\a. let f_lcl = ...f_lcl... in f_lcl
+Although I'm a bit worried about whether full laziness might
+float the f_lcl binding out and then inline M.f at its call site -}
+
+Note [Specialising in no-dict case]
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+Even if there are no tyvars or dicts, we may have specialisation pragmas.
+Class methods can generate
+ AbsBinds [] [] [( ... spec-prag]
+ { AbsBinds [tvs] [dicts] ...blah }
+So the overloading is in the nested AbsBinds. A good example is in GHC.Float:
+
+ class (Real a, Fractional a) => RealFrac a where
+ round :: (Integral b) => a -> b
+
+ instance RealFrac Float where
+ {-# SPECIALIZE round :: Float -> Int #-}
+
+The top-level AbsBinds for $cround has no tyvars or dicts (because the
+instance does not). But the method is locally overloaded!
+
+Note [Abstracting over tyvars only]
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+When abstracting over type variable only (not dictionaries), we don't really need to
+built a tuple and select from it, as we do in the general case. Instead we can take
-lhsBindArity :: LHsBind Id -> IdEnv Arity
-lhsBindArity (L _ (FunBind { fun_id = id, fun_matches = ms }))
- = unitVarEnv (unLoc id) (matchGroupArity ms)
-lhsBindArity (L _ (AbsBinds { abs_exports = exports
- , abs_dicts = dicts
- , abs_binds = binds }))
- = mkVarEnv [ (gbl, lookupArity ar_env lcl + n_val_dicts)
- | (_, gbl, lcl, _) <- exports]
- where -- See Note [Nested arities]
- ar_env = mkArityEnv binds
- n_val_dicts = dictArity dicts
+ AbsBinds [a,b] [ ([a,b], fg, fl, _),
+ ([b], gg, gl, _) ]
+ { fl = e1
+ gl = e2
+ h = e3 }
-lhsBindArity _ = emptyVarEnv -- PatBind/VarBind
+and desugar it to
-dictArity :: [Var] -> Arity
--- Don't count coercion variables in arity
-dictArity dicts = count isId dicts
+ fg = /\ab. let B in e1
+ gg = /\b. let a = () in let B in S(e2)
+ h = /\ab. let B in e3
+
+where B is the *non-recursive* binding
+ fl = fg a b
+ gl = gg b
+ h = h a b -- See (b); note shadowing!
+
+Notice (a) g has a different number of type variables to f, so we must
+ use the mkArbitraryType thing to fill in the gaps.
+ We use a type-let to do that.
+
+ (b) The local variable h isn't in the exports, and rather than
+ clone a fresh copy we simply replace h by (h a b), where
+ the two h's have different types! Shadowing happens here,
+ which looks confusing but works fine.
+
+ (c) The result is *still* quadratic-sized if there are a lot of
+ small bindings. So if there are more than some small
+ number (10), we filter the binding set B by the free
+ variables of the particular RHS. Tiresome.
+
+Why got to this trouble? It's a common case, and it removes the
+quadratic-sized tuple desugaring. Less clutter, hopefullly faster
+compilation, especially in a case where there are a *lot* of
+bindings.
-lookupArity :: IdEnv Arity -> Id -> Arity
-lookupArity ar_env id = lookupVarEnv ar_env id `orElse` 0
-\end{code}
Note [Eta-expanding INLINE things]
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
It might be better to have just one level of AbsBinds, but that requires more
thought!
+Note [Implementing SPECIALISE pragmas]
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+Example:
+ f :: (Eq a, Ix b) => a -> b -> Bool
+ {-# SPECIALISE f :: (Ix p, Ix q) => Int -> (p,q) -> Bool #-}
+ f = <poly_rhs>
+
+From this the typechecker generates
+
+ AbsBinds [ab] [d1,d2] [([ab], f, f_mono, prags)] binds
+
+ SpecPrag (wrap_fn :: forall a b. (Eq a, Ix b) => XXX
+ -> forall p q. (Ix p, Ix q) => XXX[ Int/a, (p,q)/b ])
+
+Note that wrap_fn can transform *any* function with the right type prefix
+ forall ab. (Eq a, Ix b) => XXX
+regardless of XXX. It's sort of polymorphic in XXX. This is
+useful: we use the same wrapper to transform each of the class ops, as
+well as the dict.
+
+From these we generate:
+
+ Rule: forall p, q, (dp:Ix p), (dq:Ix q).
+ f Int (p,q) dInt ($dfInPair dp dq) = f_spec p q dp dq
+
+ Spec bind: f_spec = wrap_fn <poly_rhs>
+
+Note that
+
+ * The LHS of the rule may mention dictionary *expressions* (eg
+ $dfIxPair dp dq), and that is essential because the dp, dq are
+ needed on the RHS.
+
+ * The RHS of f_spec, <poly_rhs> has a *copy* of 'binds', so that it
+ can fully specialise it.
\begin{code}
------------------------
-dsSpecs :: [TyVar] -> [DictId] -> [TyVar]
- -> Id -> Id -> Arity -- Global, local, arity of local
- -> CoreBind -> [LSpecPrag]
+dsSpecs :: Id -- The polymorphic Id
+ -> CoreExpr -- Its rhs
+ -> TcSpecPrags
-> DsM ( [(Id,CoreExpr)] -- Binding for specialised Ids
, [CoreRule] ) -- Rules for the Global Ids
--- Example:
--- f :: (Eq a, Ix b) => a -> b -> b
--- {-# SPECIALISE f :: Ix b => Int -> b -> b #-}
---
--- AbsBinds [ab] [d1,d2] [([ab], f, f_mono, prags)] binds
---
--- SpecPrag (/\b.\(d:Ix b). f Int b dInt d)
--- (forall b. Ix b => Int -> b -> b)
---
--- Rule: forall b,(d:Ix b). f Int b dInt d = f_spec b d
---
--- Spec bind: f_spec = Let f = /\ab \(d1:Eq a)(d2:Ix b). let binds in f_mono
--- /\b.\(d:Ix b). in f Int b dInt d
--- The idea is that f occurs just once, so it'll be
--- inlined and specialised
---
--- Given SpecPrag (/\as.\ds. f es) t, we have
--- the defn f_spec as ds = let-nonrec f = /\fas\fds. let f_mono = <f-rhs> in f_mono
--- in f es
--- and the RULE forall as, ds. f es = f_spec as ds
---
--- It is *possible* that 'es' does not mention all of the dictionaries 'ds'
--- (a bit silly, because then the
-
-dsSpecs all_tvs dicts tvs poly_id mono_id inl_arity mono_bind prags
- = do { pairs <- mapMaybeM spec_one prags
- ; let (spec_binds_s, rules) = unzip pairs
- ; return (concat spec_binds_s, rules) }
+-- See Note [Implementing SPECIALISE pragmas]
+dsSpecs poly_id poly_rhs prags
+ = case prags of
+ IsDefaultMethod -> return ([], [])
+ SpecPrags sps -> do { pairs <- mapMaybeM spec_one sps
+ ; let (spec_binds_s, rules) = unzip pairs
+ ; return (concat spec_binds_s, rules) }
where
- spec_one :: LSpecPrag -> DsM (Maybe ([(Id,CoreExpr)], CoreRule))
+ spec_one :: Located TcSpecPrag -> DsM (Maybe ([(Id,CoreExpr)], CoreRule))
spec_one (L loc (SpecPrag spec_co spec_inl))
= putSrcSpanDs loc $
do { let poly_name = idName poly_id
; spec_name <- newLocalName poly_name
; wrap_fn <- dsCoercion spec_co
; let ds_spec_expr = wrap_fn (Var poly_id)
+ spec_ty = exprType ds_spec_expr
; case decomposeRuleLhs ds_spec_expr of {
Nothing -> do { warnDs (decomp_msg spec_co)
; return Nothing } ;
bs | not (null bs) -> do { warnDs (dead_msg bs); return Nothing }
| otherwise -> do
- { (spec_unf, unf_pairs) <- specUnfolding wrap_fn (realIdUnfolding poly_id)
+ { (spec_unf, unf_pairs) <- specUnfolding wrap_fn spec_ty (realIdUnfolding poly_id)
- ; let f_body = fix_up (Let mono_bind (Var mono_id))
- spec_ty = exprType ds_spec_expr
- spec_id = mkLocalId spec_name spec_ty
+ ; let spec_id = mkLocalId spec_name spec_ty
`setInlinePragma` inl_prag
`setIdUnfolding` spec_unf
inl_prag | isDefaultInlinePragma spec_inl = idInlinePragma poly_id
-- Get the INLINE pragma from SPECIALISE declaration, or,
-- failing that, from the original Id
- spec_id_arity = inl_arity + count isDictId bndrs
-
- extra_dict_bndrs = [ localiseId d -- See Note [Constant rule dicts]
- | d <- varSetElems (exprFreeVars ds_spec_expr)
- , isDictId d]
- -- Note [Const rule dicts]
+ extra_dict_bndrs = [ mkLocalId (localiseName (idName d)) (idType d)
+ -- See Note [Constant rule dicts]
+ | d <- varSetElems (exprFreeVars ds_spec_expr)
+ , isDictId d]
rule = mkLocalRule (mkFastString ("SPEC " ++ showSDoc (ppr poly_name)))
AlwaysActive poly_name
(extra_dict_bndrs ++ bndrs) args
(mkVarApps (Var spec_id) bndrs)
- spec_rhs = wrap_fn (mkLams (tvs ++ dicts) f_body)
- spec_pair = makeCorePair spec_id spec_id_arity spec_rhs
+ spec_rhs = wrap_fn poly_rhs
+ spec_pair = makeCorePair spec_id False (dictArity bndrs) spec_rhs
; return (Just (spec_pair : unf_pairs, rule))
} } } }
- -- Bind to Any any of all_ptvs that aren't
- -- relevant for this particular function
- fix_up body | null void_tvs = body
- | otherwise = mkTyApps (mkLams void_tvs body) $
- map dsMkArbitraryType void_tvs
-
- void_tvs = all_tvs \\ tvs
-
dead_msg bs = vcat [ sep [ptext (sLit "Useless constraint") <> plural bs
<+> ptext (sLit "in specialied type:"),
nest 2 (pprTheta (map get_pred bs))]
2 (pprHsWrapper (ppr poly_id) spec_co)
-specUnfolding :: (CoreExpr -> CoreExpr) -> Unfolding -> DsM (Unfolding, [(Id,CoreExpr)])
-specUnfolding wrap_fn (DFunUnfolding con ops)
+specUnfolding :: (CoreExpr -> CoreExpr) -> Type
+ -> Unfolding -> DsM (Unfolding, [(Id,CoreExpr)])
+specUnfolding wrap_fn spec_ty (DFunUnfolding _ _ ops)
= do { let spec_rhss = map wrap_fn ops
; spec_ids <- mapM (mkSysLocalM (fsLit "spec") . exprType) spec_rhss
- ; return (DFunUnfolding con (map Var spec_ids), spec_ids `zip` spec_rhss) }
-specUnfolding _ _
+ ; return (mkDFunUnfolding spec_ty (map Var spec_ids), spec_ids `zip` spec_rhss) }
+specUnfolding _ _ _
= return (noUnfolding, [])
mkArbitraryTypeEnv :: [TyVar] -> [([TyVar], a, b, c)] -> TyVarEnv Type
but it seems better to reject the program because it's almost certainly
a mistake. That's what the isDeadBinder call detects.
-Note [Const rule dicts]
+Note [Constant rule dicts]
~~~~~~~~~~~~~~~~~~~~~~~
When the LHS of a specialisation rule, (/\as\ds. f es) has a free dict,
which is presumably in scope at the function definition site, we can quantify
But be careful! That dInt might be GHC.Base.$fOrdInt, which is an External
Name, and you can't bind them in a lambda or forall without getting things
-confused. Hence the use of 'localiseId' to make it Internal.
-
+confused. Likewise it might have an InlineRule or something, which would be
+utterly bogus. So we really make a fresh Id, with the same unique and type
+as the old one, but with an Internal name and no IdInfo.
%************************************************************************
%* *
data AutoScc = NoSccs
| AddSccs Module (Id -> Bool)
-- The (Id->Bool) says which Ids to add SCCs to
+-- But we never add a SCC to function marked INLINE
addAutoScc :: AutoScc
-> Id -- Binder
addAutoScc NoSccs _ rhs
= rhs
+addAutoScc _ id rhs | isInlinePragma (idInlinePragma id)
+ = rhs
addAutoScc (AddSccs mod add_scc) id rhs
| add_scc id = mkSCC (mkAutoCC id mod NotCafCC) rhs
| otherwise = rhs
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