maybeUnfoldingTemplate, otherCons, unfoldingArity,
isValueUnfolding, isEvaldUnfolding, isCheapUnfolding,
isExpandableUnfolding, isConLikeUnfolding, isCompulsoryUnfolding,
- isInlineRule, isInlineRule_maybe, isClosedUnfolding, hasSomeUnfolding,
- isStableUnfolding, canUnfold, neverUnfoldGuidance, isInlineRuleSource,
+ isStableUnfolding, isStableUnfolding_maybe,
+ isClosedUnfolding, hasSomeUnfolding,
+ canUnfold, neverUnfoldGuidance, isStableSource,
-- * Strictness
seqExpr, seqExprs, seqUnfolding,
-- They are usually variables, but can be trivial expressions
-- instead (e.g. a type application).
- | CoreUnfolding { -- An unfolding for an Id with no pragma, or perhaps a NOINLINE pragma
- -- (For NOINLINE, the phase, if any, is in the InlinePragInfo for this Id.)
+ | CoreUnfolding { -- An unfolding for an Id with no pragma,
+ -- or perhaps a NOINLINE pragma
+ -- (For NOINLINE, the phase, if any, is in the
+ -- InlinePragInfo for this Id.)
uf_tmpl :: CoreExpr, -- Template; occurrence info is correct
uf_src :: UnfoldingSource, -- Where the unfolding came from
uf_is_top :: Bool, -- True <=> top level binding
uf_arity :: Arity, -- Number of value arguments expected
- uf_is_value :: Bool, -- exprIsHNF template (cached); it is ok to discard a `seq` on
- -- this variable
- uf_is_conlike :: Bool, -- True <=> application of constructor or CONLIKE function
+ uf_is_value :: Bool, -- exprIsHNF template (cached); it is ok to discard
+ -- a `seq` on this variable
+ uf_is_conlike :: Bool, -- True <=> applicn of constructor or CONLIKE function
-- Cached version of exprIsConLike
- uf_is_cheap :: Bool, -- True <=> doesn't waste (much) work to expand inside an inlining
+ uf_is_cheap :: Bool, -- True <=> doesn't waste (much) work to expand
+ -- inside an inlining
-- Cached version of exprIsCheap
uf_expandable :: Bool, -- True <=> can expand in RULE matching
-- Cached version of exprIsExpandable
------------------------------------------------
data UnfoldingSource
- = InlineCompulsory -- Something that *has* no binding, so you *must* inline it
+ = InlineRhs -- The current rhs of the function
+ -- Replace uf_tmpl each time around
+
+ | InlineStable -- From an INLINE or INLINABLE pragma
+ -- Do not replace uf_tmpl; instead, keep it unchanged
+ -- See Note [InlineRules]
+
+ | InlineCompulsory -- Something that *has* no binding, so you *must* inline it
-- Only a few primop-like things have this property
-- (see MkId.lhs, calls to mkCompulsoryUnfolding).
-- Inline absolutely always, however boring the context.
- | InlineRule -- From an {-# INLINE #-} pragma; See Note [InlineRules]
-
| InlineWrapper Id -- This unfolding is a the wrapper in a
-- worker/wrapper split from the strictness analyser
-- The Id is the worker-id
-- which don't need to contain the RHS;
-- it can be derived from the strictness info
- | InlineRhs -- The current rhs of the function
-
- -- For InlineRhs, the uf_tmpl is replaced each time around
- -- For all the others we leave uf_tmpl alone
-- | 'UnfoldingGuidance' says when unfolding should take place
Now we might encounter (op (dfCList {ty} d) a1 a2)
and we want the (op (dfList {ty} d)) rule to fire, because $dfCList
has all its arguments, even though its (value) arity is 2. That's
-why we cache the number of expected
+why we record the number of expected arguments in the DFunUnfolding.
+Note that although it's an Arity, it's most convenient for it to give
+the *total* number of arguments, both type and value. See the use
+site in exprIsConApp_maybe.
\begin{code}
-- Constants for the UnfWhen constructor
\end{code}
\begin{code}
-isInlineRuleSource :: UnfoldingSource -> Bool
-isInlineRuleSource InlineCompulsory = True
-isInlineRuleSource InlineRule = True
-isInlineRuleSource (InlineWrapper {}) = True
-isInlineRuleSource InlineRhs = False
+isStableSource :: UnfoldingSource -> Bool
+-- Keep the unfolding template
+isStableSource InlineCompulsory = True
+isStableSource InlineStable = True
+isStableSource (InlineWrapper {}) = True
+isStableSource InlineRhs = False
-- | Retrieves the template of an unfolding: panics if none is known
unfoldingTemplate :: Unfolding -> CoreExpr
expandUnfolding_maybe (CoreUnfolding { uf_expandable = True, uf_tmpl = rhs }) = Just rhs
expandUnfolding_maybe _ = Nothing
-isInlineRule :: Unfolding -> Bool
-isInlineRule (CoreUnfolding { uf_src = src }) = isInlineRuleSource src
-isInlineRule _ = False
-
-isInlineRule_maybe :: Unfolding -> Maybe (UnfoldingSource, Bool)
-isInlineRule_maybe (CoreUnfolding { uf_src = src, uf_guidance = guide })
- | isInlineRuleSource src
+isStableUnfolding_maybe :: Unfolding -> Maybe (UnfoldingSource, Bool)
+isStableUnfolding_maybe (CoreUnfolding { uf_src = src, uf_guidance = guide })
+ | isStableSource src
= Just (src, unsat_ok)
where
unsat_ok = case guide of
UnfWhen unsat_ok _ -> unsat_ok
_ -> needSaturated
-isInlineRule_maybe _ = Nothing
+isStableUnfolding_maybe _ = Nothing
isCompulsoryUnfolding :: Unfolding -> Bool
isCompulsoryUnfolding (CoreUnfolding { uf_src = InlineCompulsory }) = True
isStableUnfolding :: Unfolding -> Bool
-- True of unfoldings that should not be overwritten
-- by a CoreUnfolding for the RHS of a let-binding
-isStableUnfolding (CoreUnfolding { uf_src = src }) = isInlineRuleSource src
+isStableUnfolding (CoreUnfolding { uf_src = src }) = isStableSource src
isStableUnfolding (DFunUnfolding {}) = True
isStableUnfolding _ = False