#14790: eqTypeRep does not inline
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Reporter: dfeuer | Owner: (none)
Type: bug | Status: new
Priority: normal | Milestone: 8.6.1
Component: Compiler | Version: 8.4.1-alpha2
Resolution: | Keywords:
Operating System: Unknown/Multiple | Architecture:
Type of failure: Runtime | Unknown/Multiple
performance bug | Test Case:
Blocked By: | Blocking:
Related Tickets: | Differential Rev(s):
Wiki Page: |
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Comment (by mpickering):
I looked at the interface file for `Data.Typeable.Internal` where
`eqTypeRep` is defined. Here is the unfolding for `eqTypeRep`.
{{{
855825a70951c01dfa45bc3067373660
eqTypeRep ::
forall k1 k2 (a :: k1) (b :: k2).
TypeRep a -> TypeRep b -> Maybe (a :~~: b)
{- Arity: 2, Strictness: ,
Unfolding: (\ @ k1
@ k2
@ a :: k1
@ b :: k2
(a1 :: TypeRep a)
(b1 :: TypeRep b) ->
let {
$j :: Word# -> Word# -> Maybe (a :~~: b)
{- Arity: 2, Strictness: -}
= \ (dt :: Word#)[OneShot] (dt1 :: Word#)[OneShot] ->
case b1 of wild {
TrType co co1
-> case fpTYPELiftedRep of wild1 { Fingerprint dt2
dt3 ->
case eqWord# dt dt2 of lwild {
DEFAULT -> Nothing @ (a :~~: b)
1#
-> case eqWord# dt1 dt3 of lwild1 {
DEFAULT -> Nothing @ (a :~~: b)
1# -> eqTypeRep1 @ k1 @ a @ k2 @ b } } }
TrTyCon dt2 dt3 ds ds1 ds2
-> case eqWord# dt dt2 of lwild {
DEFAULT -> Nothing @ (a :~~: b)
1#
-> case eqWord# dt1 dt3 of lwild1 {
DEFAULT -> Nothing @ (a :~~: b)
1# -> eqTypeRep1 @ k1 @ a @ k2 @ b } }
TrApp k4 a2 b2 co dt2 dt3 ds ds1 ds2
-> case eqWord# dt dt2 of lwild {
DEFAULT -> Nothing @ (a :~~: b)
1#
-> case eqWord# dt1 dt3 of lwild1 {
DEFAULT -> Nothing @ (a :~~: b)
1# -> eqTypeRep1 @ k1 @ a @ k2 @ b } }
TrFun r1 r2 a2 b2 co co1 dt2 dt3 ds ds1
-> case eqWord# dt dt2 of lwild {
DEFAULT -> Nothing @ (a :~~: b)
1#
-> case eqWord# dt1 dt3 of lwild1 {
DEFAULT -> Nothing @ (a :~~: b)
1# -> eqTypeRep1 @ k1 @ a @ k2 @ b } } }
} in
case a1 of wild {
TrType co co1
-> case fpTYPELiftedRep of wild1 { Fingerprint dt dt1
->
$j dt dt1 }
TrTyCon dt dt1 ds ds1 ds2 -> $j dt dt1
TrApp k4 a2 b2 co dt dt1 ds ds1 ds2 -> $j dt dt1
TrFun r1 r2 a2 b2 co co1 dt dt1 ds ds1 -> $j dt dt1 }) -}
}}}
It appears that both functions I mentioned above are inlined (to no great
effect) which make the definition quite large.
--
Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/14790#comment:8
GHC http://www.haskell.org/ghc/
The Glasgow Haskell Compiler
