2 % (c) The AQUA Project, Glasgow University, 1994-1996
4 \section[CoreUnfold]{Core-syntax unfoldings}
6 Unfoldings (which can travel across module boundaries) are in Core
7 syntax (namely @CoreExpr@s).
9 The type @UnfoldingDetails@ sits ``above'' simply-Core-expressions
10 unfoldings, capturing ``higher-level'' things we know about a binding,
11 usually things that the simplifier found out (e.g., ``it's a
12 literal''). In the corner of a @GenForm@ unfolding, you will
13 find, unsurprisingly, a Core expression.
16 #include "HsVersions.h"
19 UnfoldingDetails(..), UnfoldingGuidance(..), -- types
25 modifyUnfoldingDetails,
26 calcUnfoldingGuidance,
31 import IdLoop -- for paranoia checking;
32 -- and also to get mkMagicUnfoldingFun
33 import PrelLoop -- for paranoia checking
35 import Bag ( emptyBag, unitBag, unionBags, Bag )
36 import BinderInfo ( oneTextualOcc, oneSafeOcc )
37 import CgCompInfo ( uNFOLDING_CHEAP_OP_COST,
38 uNFOLDING_DEAR_OP_COST,
39 uNFOLDING_NOREP_LIT_COST
42 import CoreUtils ( coreExprType, manifestlyWHNF )
43 import CostCentre ( ccMentionsId )
44 import Id ( IdSet(..), GenId{-instances-} )
45 import IdInfo ( bottomIsGuaranteed )
46 import Literal ( isNoRepLit, isLitLitLit )
48 import PrimOp ( primOpCanTriggerGC, PrimOp(..) )
49 import TyCon ( tyConFamilySize )
50 import Type ( getAppDataTyCon )
51 import UniqSet ( emptyUniqSet, unitUniqSet, mkUniqSet,
52 addOneToUniqSet, unionUniqSets
54 import Usage ( UVar(..) )
55 import Util ( isIn, panic )
57 whatsMentionedInId = panic "whatsMentionedInId (CoreUnfold)"
58 getMentionedTyConsAndClassesFromType = panic "getMentionedTyConsAndClassesFromType (CoreUnfold)"
61 %************************************************************************
63 \subsection{@UnfoldingDetails@ and @UnfoldingGuidance@ types}
65 %************************************************************************
67 (And @FormSummary@, too.)
77 [Literal] -- It is a literal, but definitely not one of these
81 [CoreArg] -- Type/value arguments; NB OutArgs, already cloned
84 [Id] -- It definitely isn't one of these constructors
85 -- This captures the situation in the default branch of
90 -- Then in default-rhs we know that v isn't c1 or c2.
92 -- NB. In the degenerate: case x of {v -> default-rhs}
95 -- which captures the idea that x is eval'd but we don't
96 -- know which constructor.
100 Bool -- True <=> At most one textual occurrence of the
101 -- binder in its scope, *or*
102 -- if we are happy to duplicate this
104 FormSummary -- Tells whether the template is a WHNF or bottom
105 TemplateOutExpr -- The template
106 UnfoldingGuidance -- Tells about the *size* of the template.
109 Unique -- of the Id whose magic unfolding this is
112 type TemplateOutExpr = GenCoreExpr (Id, BinderInfo) Id TyVar UVar
113 -- An OutExpr with occurrence info attached. This is used as
114 -- a template in GeneralForms.
116 mkMagicUnfolding :: Unique -> UnfoldingDetails
117 mkMagicUnfolding tag = MagicForm tag (mkMagicUnfoldingFun tag)
120 = WhnfForm -- Expression is WHNF
121 | BottomForm -- Expression is guaranteed to be bottom. We're more gung
122 -- ho about inlining such things, because it can't waste work
123 | OtherForm -- Anything else
125 instance Outputable FormSummary where
126 ppr sty WhnfForm = ppStr "WHNF"
127 ppr sty BottomForm = ppStr "Bot"
128 ppr sty OtherForm = ppStr "Other"
130 --???mkFormSummary :: StrictnessInfo -> GenCoreExpr bndr Id -> FormSummary
131 mkFormSummary si expr
132 | manifestlyWHNF expr = WhnfForm
133 | bottomIsGuaranteed si = BottomForm
135 -- Chances are that the Id will be decorated with strictness info
136 -- telling that the RHS is definitely bottom. This *might* not be the
137 -- case, if it's been a while since strictness analysis, but leaving out
138 -- the test for manifestlyBottom makes things a little more efficient.
139 -- We can always put it back...
140 -- | manifestlyBottom expr = BottomForm
142 | otherwise = OtherForm
146 data UnfoldingGuidance
147 = UnfoldNever -- Don't do it!
149 | UnfoldAlways -- There is no "original" definition,
150 -- so you'd better unfold. Or: something
151 -- so cheap to unfold (e.g., 1#) that
152 -- you should do it absolutely always.
154 | EssentialUnfolding -- Like UnfoldAlways, but you *must* do
155 -- it absolutely always.
156 -- This is what we use for data constructors
157 -- and PrimOps, because we don't feel like
158 -- generating curried versions "just in case".
160 | UnfoldIfGoodArgs Int -- if "m" type args and "n" value args; and
161 Int -- those val args are manifestly data constructors
162 [Bool] -- the val-arg positions marked True
163 -- (i.e., a simplification will definitely
165 Int -- The "size" of the unfolding; to be elaborated
168 | BadUnfolding -- This is used by TcPragmas if the *lazy*
169 -- lintUnfolding test fails
170 -- It will never escape from the IdInfo as
171 -- it is caught by getInfo_UF and converted
172 -- to NoUnfoldingDetails
176 instance Outputable UnfoldingGuidance where
177 ppr sty UnfoldNever = ppStr "_N_"
178 ppr sty UnfoldAlways = ppStr "_ALWAYS_"
179 ppr sty EssentialUnfolding = ppStr "_ESSENTIAL_" -- shouldn't appear in an iface
180 ppr sty (UnfoldIfGoodArgs t v cs size)
181 = ppCat [ppStr "_IF_ARGS_", ppInt t, ppInt v,
182 if null cs -- always print *something*
184 else ppBesides (map pp_c cs),
187 pp_c False = ppChar 'X'
188 pp_c True = ppChar 'C'
192 %************************************************************************
194 \subsection{@mkGenForm@ and @modifyUnfoldingDetails@}
196 %************************************************************************
199 mkGenForm :: Bool -- Ok to Dup code down different case branches,
200 -- because of either a flag saying so,
201 -- or alternatively the object is *SMALL*
204 -> TemplateOutExpr -- Template
205 -> UnfoldingGuidance -- Tells about the *size* of the template.
208 mkGenForm safe_to_dup occ_info WhnfForm template guidance
209 = GenForm (oneTextualOcc safe_to_dup occ_info) WhnfForm template guidance
211 mkGenForm safe_to_dup occ_info form_summary template guidance
212 | oneSafeOcc safe_to_dup occ_info -- Non-WHNF with only safe occurrences
213 = GenForm True form_summary template guidance
215 | otherwise -- Not a WHNF, many occurrences
220 modifyUnfoldingDetails
222 -> BinderInfo -- New occurrence info for the thing
226 modifyUnfoldingDetails ok_to_dup occ_info
227 (GenForm only_one form_summary template guidance)
228 | only_one = mkGenForm ok_to_dup occ_info form_summary template guidance
230 modifyUnfoldingDetails ok_to_dup occ_info other = other
234 %************************************************************************
236 \subsection[calcUnfoldingGuidance]{Calculate ``unfolding guidance'' for an expression}
238 %************************************************************************
241 calcUnfoldingGuidance
242 :: Bool -- True <=> OK if _scc_s appear in expr
243 -> Int -- bomb out if size gets bigger than this
244 -> CoreExpr -- expression to look at
247 calcUnfoldingGuidance scc_s_OK bOMB_OUT_SIZE expr
249 (use_binders, ty_binders, val_binders, body) = collectBinders expr
251 case (sizeExpr scc_s_OK bOMB_OUT_SIZE val_binders body) of
253 Nothing -> UnfoldNever
255 Just (size, cased_args)
257 uf = UnfoldIfGoodArgs
260 [ b `is_elem` cased_args | b <- val_binders ]
263 -- pprTrace "calcUnfold:" (ppAbove (ppr PprDebug uf) (ppr PprDebug expr))
266 is_elem = isIn "calcUnfoldingGuidance"
270 sizeExpr :: Bool -- True <=> _scc_s OK
271 -> Int -- Bomb out if it gets bigger than this
272 -> [Id] -- Arguments; we're interested in which of these
275 -> Maybe (Int, -- Size
276 [Id] -- Subset of args which are cased
279 sizeExpr scc_s_OK bOMB_OUT_SIZE args expr
282 size_up (Var v) = sizeOne
283 size_up (App fun arg) = size_up fun `addSize` size_up_arg arg
284 size_up (Lit lit) = if isNoRepLit lit
285 then sizeN uNFOLDING_NOREP_LIT_COST
288 size_up (SCC _ (Con _ _)) = Nothing -- **** HACK *****
289 size_up (SCC lbl body)
290 = if scc_s_OK then size_up body else Nothing
292 size_up (Coerce _ _ body) = size_up body
294 size_up (Con con args) = -- 1 + # of val args
295 sizeN (1 + numValArgs args)
296 size_up (Prim op args) = sizeN op_cost -- NB: no charge for PrimOp args
298 op_cost = if primOpCanTriggerGC op
299 then uNFOLDING_DEAR_OP_COST
300 -- these *tend* to be more expensive;
301 -- number chosen to avoid unfolding (HACK)
302 else uNFOLDING_CHEAP_OP_COST
304 size_up expr@(Lam _ _)
306 (uvars, tyvars, args, body) = collectBinders expr
308 size_up body `addSizeN` length args
310 size_up (Let (NonRec binder rhs) body)
317 size_up (Let (Rec pairs) body)
318 = foldr addSize sizeZero [size_up rhs | (_,rhs) <- pairs]
324 size_up (Case scrut alts)
325 = size_up_scrut scrut
327 size_up_alts (coreExprType scrut) alts
328 -- We charge for the "case" itself in "size_up_alts"
331 size_up_arg arg = if isValArg arg then sizeOne else sizeZero{-it's free-}
334 size_up_alts scrut_ty (AlgAlts alts deflt)
335 = foldr (addSize . size_alg_alt) (size_up_deflt deflt) alts
336 `addSizeN` (tyConFamilySize tycon)
337 -- NB: we charge N for an alg. "case", where N is
338 -- the number of constructors in the thing being eval'd.
339 -- (You'll eventually get a "discount" of N if you
340 -- think the "case" is likely to go away.)
342 size_alg_alt (con,args,rhs) = size_up rhs
343 -- Don't charge for args, so that wrappers look cheap
345 (tycon, _, _) = _trace "getAppDataTyCon.CoreUnfold" $ getAppDataTyCon scrut_ty
347 size_up_alts _ (PrimAlts alts deflt)
348 = foldr (addSize . size_prim_alt) (size_up_deflt deflt) alts
349 -- *no charge* for a primitive "case"!
351 size_prim_alt (lit,rhs) = size_up rhs
354 size_up_deflt NoDefault = sizeZero
355 size_up_deflt (BindDefault binder rhs) = size_up rhs
358 -- Scrutinees. There are two things going on here.
359 -- First, we want to record if we're case'ing an argument
360 -- Second, we want to charge nothing for the srutinee if it's just
361 -- a variable. That way wrapper-like things look cheap.
362 size_up_scrut (Var v) | v `is_elem` args = Just (0, [v])
363 | otherwise = Just (0, [])
364 size_up_scrut other = size_up other
366 is_elem :: Id -> [Id] -> Bool
367 is_elem = isIn "size_up_scrut"
370 sizeZero = Just (0, [])
371 sizeOne = Just (1, [])
372 sizeN n = Just (n, [])
373 sizeVar v = Just (0, [v])
375 addSizeN Nothing _ = Nothing
376 addSizeN (Just (n, xs)) m
377 | tot < bOMB_OUT_SIZE = Just (tot, xs)
378 | otherwise = Nothing
382 addSize Nothing _ = Nothing
383 addSize _ Nothing = Nothing
384 addSize (Just (n, xs)) (Just (m, ys))
385 | tot < bOMB_OUT_SIZE = Just (tot, xys)
386 | otherwise = Nothing
392 %************************************************************************
394 \subsection[unfoldings-for-ifaces]{Processing unfoldings for interfaces}
396 %************************************************************************
398 Of course, the main thing we do to unfoldings-for-interfaces is {\em
399 print} them. But, while we're at it, we collect info about
400 ``mentioned'' Ids, etc., etc.---we're going to need this stuff anyway.
402 %************************************************************************
404 \subsubsection{Monad stuff for the unfolding-generation game}
406 %************************************************************************
409 type UnfoldM bndr thing
410 = IdSet -- in-scope Ids (passed downwards only)
411 -> (bndr -> Id) -- to extract an Id from a binder (down only)
413 -> (Bag Id, -- mentioned global vars (ditto)
414 Bag TyCon, -- ditto, tycons
415 Bag Class, -- ditto, classes
416 Bool) -- True <=> mentions something litlit-ish
418 -> (thing, (Bag Id, Bag TyCon, Bag Class, Bool)) -- accumulated...
421 A little stuff for in-scopery:
423 no_in_scopes :: IdSet
424 add1 :: IdSet -> Id -> IdSet
425 add_some :: IdSet -> [Id] -> IdSet
427 no_in_scopes = emptyUniqSet
428 in_scopes `add1` x = addOneToUniqSet in_scopes x
429 in_scopes `add_some` xs = in_scopes `unionUniqSets` mkUniqSet xs
432 The can-see-inside-monad functions are the usual sorts of things.
435 thenUf :: UnfoldM bndr a -> (a -> UnfoldM bndr b) -> UnfoldM bndr b
436 thenUf m k in_scopes get_id mentioneds
437 = case m in_scopes get_id mentioneds of { (v, mentioneds1) ->
438 k v in_scopes get_id mentioneds1 }
440 thenUf_ :: UnfoldM bndr a -> UnfoldM bndr b -> UnfoldM bndr b
441 thenUf_ m k in_scopes get_id mentioneds
442 = case m in_scopes get_id mentioneds of { (_, mentioneds1) ->
443 k in_scopes get_id mentioneds1 }
445 mapUf :: (a -> UnfoldM bndr b) -> [a] -> UnfoldM bndr [b]
446 mapUf f [] = returnUf []
448 = f x `thenUf` \ r ->
449 mapUf f xs `thenUf` \ rs ->
452 returnUf :: a -> UnfoldM bndr a
453 returnUf v in_scopes get_id mentioneds = (v, mentioneds)
455 addInScopesUf :: [Id] -> UnfoldM bndr a -> UnfoldM bndr a
456 addInScopesUf more_in_scopes m in_scopes get_id mentioneds
457 = m (in_scopes `add_some` more_in_scopes) get_id mentioneds
459 getInScopesUf :: UnfoldM bndr IdSet
460 getInScopesUf in_scopes get_id mentioneds = (in_scopes, mentioneds)
462 extractIdsUf :: [bndr] -> UnfoldM bndr [Id]
463 extractIdsUf binders in_scopes get_id mentioneds
464 = (map get_id binders, mentioneds)
466 consider_Id :: Id -> UnfoldM bndr ()
467 consider_Id var in_scopes get_id (ids, tcs, clss, has_litlit)
469 (ids2, tcs2, clss2) = whatsMentionedInId in_scopes var
471 ((), (ids `unionBags` ids2,
472 tcs `unionBags` tcs2,
473 clss `unionBags`clss2,
478 addToMentionedIdsUf :: Id -> UnfoldM bndr ()
479 addToMentionedTyConsUf :: Bag TyCon -> UnfoldM bndr ()
480 addToMentionedClassesUf :: Bag Class -> UnfoldM bndr ()
481 litlit_oops :: UnfoldM bndr ()
483 addToMentionedIdsUf add_me in_scopes get_id (ids, tcs, clss, has_litlit)
484 = ((), (ids `unionBags` unitBag add_me, tcs, clss, has_litlit))
486 addToMentionedTyConsUf add_mes in_scopes get_id (ids, tcs, clss, has_litlit)
487 = ((), (ids, tcs `unionBags` add_mes, clss, has_litlit))
489 addToMentionedClassesUf add_mes in_scopes get_id (ids, tcs, clss, has_litlit)
490 = ((), (ids, tcs, clss `unionBags` add_mes, has_litlit))
492 litlit_oops in_scopes get_id (ids, tcs, clss, _)
493 = ((), (ids, tcs, clss, True))
497 %************************************************************************
499 \subsubsection{Gathering up info for an interface-unfolding}
501 %************************************************************************
506 :: (bndr -> Id) -- so we can get Ids out of binders
507 -> GenCoreExpr bndr Id -- input expression
508 -> (Bag Id, Bag TyCon, Bag Class,
509 -- what we found mentioned in the expr
510 Bool -- True <=> mentions a ``litlit''-ish thing
511 -- (the guy on the other side of an interface
512 -- may not be able to handle it)
516 mentionedInUnfolding get_id expr
517 = case (ment_expr expr no_in_scopes get_id (emptyBag, emptyBag, emptyBag, False)) of
518 (_, (ids_bag, tcs_bag, clss_bag, has_litlit)) ->
519 (ids_bag, tcs_bag, clss_bag, has_litlit)
523 --ment_expr :: GenCoreExpr bndr Id -> UnfoldM bndr ()
525 ment_expr (Var v) = consider_Id v
526 ment_expr (Lit l) = consider_lit l
528 ment_expr expr@(Lam _ _)
530 (uvars, tyvars, args, body) = collectBinders expr
532 extractIdsUf args `thenUf` \ bs_ids ->
533 addInScopesUf bs_ids (
534 -- this considering is just to extract any mentioned types/classes
535 mapUf consider_Id bs_ids `thenUf_`
539 ment_expr (App fun arg)
540 = ment_expr fun `thenUf_`
544 = consider_Id c `thenUf_`
545 mapUf ment_arg as `thenUf_`
548 ment_expr (Prim op as)
549 = ment_op op `thenUf_`
550 mapUf ment_arg as `thenUf_`
553 ment_op (CCallOp str is_asm may_gc arg_tys res_ty)
554 = mapUf ment_ty arg_tys `thenUf_`
556 ment_op other_op = returnUf ()
558 ment_expr (Case scrutinee alts)
559 = ment_expr scrutinee `thenUf_`
562 ment_expr (Let (NonRec bind rhs) body)
563 = ment_expr rhs `thenUf_`
564 extractIdsUf [bind] `thenUf` \ bi@[bind_id] ->
566 ment_expr body `thenUf_`
567 consider_Id bind_id )
569 ment_expr (Let (Rec pairs) body)
571 binders = map fst pairs
574 extractIdsUf binders `thenUf` \ binder_ids ->
575 addInScopesUf binder_ids (
576 mapUf ment_expr rhss `thenUf_`
577 mapUf consider_Id binder_ids `thenUf_`
580 ment_expr (SCC cc expr)
581 = (case (ccMentionsId cc) of
582 Just id -> consider_Id id
583 Nothing -> returnUf ()
585 `thenUf_` ment_expr expr
587 ment_expr (Coerce _ _ _) = panic "ment_expr:Coerce"
592 (tycons, clss) = getMentionedTyConsAndClassesFromType ty
594 addToMentionedTyConsUf tycons `thenUf_`
595 addToMentionedClassesUf clss
599 ment_alts alg_alts@(AlgAlts alts deflt)
600 = mapUf ment_alt alts `thenUf_`
603 ment_alt alt@(con, params, rhs)
604 = consider_Id con `thenUf_`
605 extractIdsUf params `thenUf` \ param_ids ->
606 addInScopesUf param_ids (
607 -- "consider" them so we can chk out their types...
608 mapUf consider_Id param_ids `thenUf_`
611 ment_alts (PrimAlts alts deflt)
612 = mapUf ment_alt alts `thenUf_`
615 ment_alt alt@(lit, rhs) = ment_expr rhs
621 ment_deflt d@(BindDefault b rhs)
622 = extractIdsUf [b] `thenUf` \ bi@[b_id] ->
624 consider_Id b_id `thenUf_`
628 ment_arg (VarArg v) = consider_Id v
629 ment_arg (LitArg l) = consider_lit l
630 ment_arg (TyArg ty) = ment_ty ty
631 ment_arg (UsageArg _) = returnUf ()
635 | isLitLitLit lit = litlit_oops `thenUf_` returnUf ()
636 | otherwise = returnUf ()
639 %************************************************************************
641 \subsubsection{Printing unfoldings in interfaces}
643 %************************************************************************
645 Printing Core-expression unfoldings is sufficiently delicate that we
646 give it its own function.
653 pprCoreUnfolding expr
655 (_, renamed) = instCoreExpr uniqSupply_u expr
656 -- We rename every unfolding with a "steady" unique supply,
657 -- so that the names won't constantly change.
658 -- One place we *MUST NOT* use a splittable UniqueSupply!
660 ppr_uf_Expr emptyUniqSet renamed
662 ppr_Unfolding = PprUnfolding (panic "CoreUnfold:ppr_Unfolding")
666 ppr_uf_Expr in_scopes (Var v) = pprIdInUnfolding in_scopes v
667 ppr_uf_Expr in_scopes (Lit l) = ppr ppr_Unfolding l
669 ppr_uf_Expr in_scopes (Con c as)
670 = ppBesides [ppPStr SLIT("_!_ "), pprIdInUnfolding no_in_scopes c, ppSP,
671 ppLbrack, ppIntersperse pp'SP{-'-} (map (pprParendUniType ppr_Unfolding) ts), ppRbrack,
672 ppSP, ppLbrack, ppIntersperse pp'SP{-'-} (map (ppr_uf_Atom in_scopes) as), ppRbrack]
673 ppr_uf_Expr in_scopes (Prim op as)
674 = ppBesides [ppPStr SLIT("_#_ "), ppr ppr_Unfolding op, ppSP,
675 ppLbrack, ppIntersperse pp'SP{-'-} (map (pprParendUniType ppr_Unfolding) ts), ppRbrack,
676 ppSP, ppLbrack, ppIntersperse pp'SP{-'-} (map (ppr_uf_Atom in_scopes) as), ppRbrack]
678 ppr_uf_Expr in_scopes (Lam binder body)
679 = ppCat [ppChar '\\', ppr_uf_Binder binder,
680 ppPStr SLIT("->"), ppr_uf_Expr (in_scopes `add1` binder) body]
682 ppr_uf_Expr in_scopes (CoTyLam tyvar expr)
683 = ppCat [ppPStr SLIT("_/\\_"), interppSP ppr_Unfolding (tyvar:tyvars), ppStr "->",
684 ppr_uf_Expr in_scopes body]
686 (tyvars, body) = collect_tyvars expr
688 collect_tyvars (CoTyLam tyv e) = ( tyv:tyvs, e_after )
689 where (tyvs, e_after) = collect_tyvars e
690 collect_tyvars other_e = ( [], other_e )
692 ppr_uf_Expr in_scopes expr@(App fun_expr atom)
694 (fun, args) = collect_args expr []
696 ppCat [ppPStr SLIT("_APP_ "), ppr_uf_Expr in_scopes fun, ppLbrack,
697 ppIntersperse pp'SP{-'-} (map (ppr_uf_Atom in_scopes) args), ppRbrack]
699 collect_args (App fun arg) args = collect_args fun (arg:args)
700 collect_args fun args = (fun, args)
702 ppr_uf_Expr in_scopes (CoTyApp expr ty)
703 = ppCat [ppPStr SLIT("_TYAPP_ "), ppr_uf_Expr in_scopes expr,
704 ppChar '{', pprParendUniType ppr_Unfolding ty, ppChar '}']
706 ppr_uf_Expr in_scopes (Case scrutinee alts)
707 = ppCat [ppPStr SLIT("case"), ppr_uf_Expr in_scopes scrutinee, ppStr "of {",
708 pp_alts alts, ppChar '}']
710 pp_alts (AlgAlts alts deflt)
711 = ppCat [ppPStr SLIT("_ALG_"), ppCat (map pp_alg alts), pp_deflt deflt]
712 pp_alts (PrimAlts alts deflt)
713 = ppCat [ppPStr SLIT("_PRIM_"), ppCat (map pp_prim alts), pp_deflt deflt]
715 pp_alg (con, params, rhs)
716 = ppBesides [pprIdInUnfolding no_in_scopes con, ppSP,
717 ppIntersperse ppSP (map ppr_uf_Binder params),
718 ppPStr SLIT(" -> "), ppr_uf_Expr (in_scopes `add_some` params) rhs, ppSemi]
721 = ppBesides [ppr ppr_Unfolding lit,
722 ppPStr SLIT(" -> "), ppr_uf_Expr in_scopes rhs, ppSemi]
724 pp_deflt NoDefault = ppPStr SLIT("_NO_DEFLT_")
725 pp_deflt (BindDefault binder rhs)
726 = ppBesides [ppr_uf_Binder binder, ppPStr SLIT(" -> "),
727 ppr_uf_Expr (in_scopes `add1` binder) rhs]
729 ppr_uf_Expr in_scopes (Let (NonRec binder rhs) body)
730 = ppBesides [ppStr "let {", ppr_uf_Binder binder, ppPStr SLIT(" = "), ppr_uf_Expr in_scopes rhs,
731 ppStr "} in ", ppr_uf_Expr (in_scopes `add1` binder) body]
733 ppr_uf_Expr in_scopes (Let (Rec pairs) body)
734 = ppBesides [ppStr "_LETREC_ {", ppIntersperse sep (map pp_pair pairs),
735 ppStr "} in ", ppr_uf_Expr new_in_scopes body]
737 sep = ppBeside ppSemi ppSP
738 new_in_scopes = in_scopes `add_some` map fst pairs
740 pp_pair (b, rhs) = ppCat [ppr_uf_Binder b, ppEquals, ppr_uf_Expr new_in_scopes rhs]
742 ppr_uf_Expr in_scopes (SCC cc body)
743 = ASSERT(not (noCostCentreAttached cc))
744 ASSERT(not (currentOrSubsumedCosts cc))
745 ppBesides [ppStr "_scc_ { ", ppStr (showCostCentre ppr_Unfolding False{-not as string-} cc), ppStr " } ", ppr_uf_Expr in_scopes body]
747 ppr_uf_Expr in_scopes (Coerce _ _ _) = panic "ppr_uf_Expr:Coerce"
751 ppr_uf_Binder :: Id -> Pretty
753 = ppBesides [ppLparen, pprIdInUnfolding (unitUniqSet v) v, ppPStr SLIT(" :: "),
754 ppr ppr_Unfolding (idType v), ppRparen]
756 ppr_uf_Atom in_scopes (LitArg l) = ppr ppr_Unfolding l
757 ppr_uf_Atom in_scopes (VarArg v) = pprIdInUnfolding in_scopes v