From 2ea586cee99f25030622e0b8dec371c35bd745b8 Mon Sep 17 00:00:00 2001
From: sof <unknown>
Date: Tue, 9 Sep 1997 18:07:41 +0000
Subject: [PATCH] [project @ 1997-09-09 18:07:41 by sof] moved: okToInline (to
BinderInfo); new function: inlineUnconditionally; Type of whnfOrBottom
changed
---
ghc/compiler/coreSyn/CoreUnfold.lhs | 64 +++++++++++++----------------
1 file changed, 28 insertions(+), 36 deletions(-)
diff --git a/ghc/compiler/coreSyn/CoreUnfold.lhs b/ghc/compiler/coreSyn/CoreUnfold.lhs
index bf75aa02f0c2..36a6746567aa 100644
--- a/ghc/compiler/coreSyn/CoreUnfold.lhs
+++ b/ghc/compiler/coreSyn/CoreUnfold.lhs
@@ -24,7 +24,7 @@ module CoreUnfold (
noUnfolding, mkMagicUnfolding, mkUnfolding, getUnfoldingTemplate,
smallEnoughToInline, couldBeSmallEnoughToInline, certainlySmallEnoughToInline,
- okToInline,
+ inlineUnconditionally,
calcUnfoldingGuidance,
@@ -51,7 +51,8 @@ import Constants ( uNFOLDING_CHEAP_OP_COST,
uNFOLDING_DEAR_OP_COST,
uNFOLDING_NOREP_LIT_COST
)
-import BinderInfo ( BinderInfo(..), FunOrArg, DuplicationDanger, InsideSCC, isDupDanger )
+import BinderInfo ( BinderInfo, isOneFunOcc, isOneSafeFunOcc
+ )
import PragmaInfo ( PragmaInfo(..) )
import CoreSyn
import CoreUtils ( unTagBinders )
@@ -60,7 +61,8 @@ import RdrHsSyn ( RdrName )
import OccurAnal ( occurAnalyseGlobalExpr )
import CoreUtils ( coreExprType )
--import CostCentre ( ccMentionsId )
-import Id ( SYN_IE(Id), idType, getIdArity, isBottomingId, isDataCon, --rm: isPrimitiveId_maybe,
+import Id ( SYN_IE(Id), idType, getIdArity, isBottomingId, isDataCon,
+ idWantsToBeINLINEd, idMustBeINLINEd, idMustNotBeINLINEd,
SYN_IE(IdSet), GenId{-instances-} )
import PrimOp ( primOpCanTriggerGC, fragilePrimOp, PrimOp(..) )
import IdInfo ( ArityInfo(..), bottomIsGuaranteed )
@@ -213,12 +215,11 @@ mkFormSummary expr
ArityAtLeast a | n < a -> ValueForm
other -> OtherForm
-whnfOrBottom :: GenCoreExpr bndr Id tyvar uvar -> Bool
-whnfOrBottom e = case mkFormSummary e of
- VarForm -> True
- ValueForm -> True
- BottomForm -> True
- OtherForm -> False
+whnfOrBottom :: FormSummary -> Bool
+whnfOrBottom VarForm = True
+whnfOrBottom ValueForm = True
+whnfOrBottom BottomForm = True
+whnfOrBottom OtherForm = False
\end{code}
@exprIsTrivial@ is true of expressions we are unconditionally happy to duplicate;
@@ -514,33 +515,24 @@ certainlySmallEnoughToInline guidance = smallEnoughToInline (repeat False) False
Predicates
~~~~~~~~~~
+@inlineUnconditionally@ decides whether a let-bound thing can
+*definitely* be inlined at each of its call sites. If so, then
+we can drop the binding right away. But remember, you have to be
+certain that every use can be inlined. So, notably, any ArgOccs
+rule this out. Since ManyOcc doesn't record FunOcc/ArgOcc
+
\begin{code}
-okToInline
- :: FormSummary -- What the thing to be inlined is like
- -> BinderInfo -- How the thing to be inlined occurs
- -> Bool -- True => it's small enough to inline
- -> Bool -- True => yes, inline it
-
--- If there's no danger of duplicating work, we can inline if it occurs once, or is small
-okToInline form occ_info small_enough
- | no_dup_danger form
- = small_enough || one_occ
- where
- one_occ = case occ_info of
- OneOcc _ _ _ n_alts _ -> n_alts <= 1
- other -> False
-
- no_dup_danger VarForm = True
- no_dup_danger ValueForm = True
- no_dup_danger BottomForm = True
- no_dup_danger other = False
-
--- A non-WHNF can be inlined if it doesn't occur inside a lambda,
--- and occurs exactly once or
--- occurs once in each branch of a case and is small
-okToInline OtherForm (OneOcc _ dup_danger _ n_alts _) small_enough
- = not (isDupDanger dup_danger) && (n_alts <= 1 || small_enough)
+inlineUnconditionally :: Bool -> Id -> BinderInfo -> Bool
-okToInline form any_occ small_enough = False
-\end{code}
+inlineUnconditionally ok_to_dup id occ_info
+ | idMustNotBeINLINEd id = False
+ | isOneFunOcc occ_info
+ && idMustBeINLINEd id = True
+
+ | isOneSafeFunOcc (ok_to_dup || idWantsToBeINLINEd id) occ_info
+ = True
+
+ | otherwise
+ = False
+\end{code}
--
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