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| author | Matthew Pickering <matthewtpickering@gmail.com> | 2023-01-27 10:04:38 +0000 |
|---|---|---|
| committer | Matthew Pickering <matthewtpickering@gmail.com> | 2023-02-01 09:51:14 +0000 |
| commit | a060fa30a2149aa498d847ce441ac696b1ed04d5 (patch) | |
| tree | b161db3a583d0222501ac88222e749385846b629 /compiler | |
| parent | 545bf8cf1844e2a1c18d2019d1f299ab10099873 (diff) | |
| download | haskell-wip/disable-iface-sharing.tar.gz | |
Disable unfolding sharing for interface files with core definitionswip/disable-iface-sharing
Ticket #22807 pointed out that the RHS sharing was not compatible with
-fignore-interface-pragmas because the flag would remove unfoldings from
identifiers before the `extra-decls` field was populated.
For the 9.6 timescale the only solution is to disable this sharing,
which will make interface files bigger but this is acceptable for the
first release of `-fwrite-if-simplified-core`.
For 9.8 it would be good to fix this by implementing #20056 due to the
large number of other bugs that would fix.
I also improved the error message in tc_iface_binding to avoid the "no match
in record selector" error but it should never happen now as the entire
sharing logic is disabled.
Also added the currently broken test for #22807 which could be fixed by
!6080
Fixes #22807
Diffstat (limited to 'compiler')
| -rw-r--r-- | compiler/GHC/CoreToIface.hs | 13 | ||||
| -rw-r--r-- | compiler/GHC/IfaceToCore.hs | 8 |
2 files changed, 17 insertions, 4 deletions
diff --git a/compiler/GHC/CoreToIface.hs b/compiler/GHC/CoreToIface.hs index bf713aae53..ed8a68560b 100644 --- a/compiler/GHC/CoreToIface.hs +++ b/compiler/GHC/CoreToIface.hs @@ -604,8 +604,12 @@ toIfaceTopBind b = IfLclTopBndr {} -> IfRhs (toIfaceExpr rhs) in (top_bndr, rhs') - already_has_unfolding b = - -- The identifier has an unfolding, which we are going to serialise anyway + -- The sharing behaviour is currently disabled due to #22807, and relies on + -- finished #220056 to be re-enabled. + disabledDueTo22807 = True + + already_has_unfolding b = not disabledDueTo22807 + && -- The identifier has an unfolding, which we are going to serialise anyway hasCoreUnfolding (realIdUnfolding b) -- But not a stable unfolding, we want the optimised unfoldings. && not (isStableUnfolding (realIdUnfolding b)) @@ -771,7 +775,10 @@ is that these NOINLINE'd functions now can't be profitably inlined outside of the hs-boot loop. Note [Interface File with Core: Sharing RHSs] -~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +IMPORTANT: This optimisation is currently disabled due to #22027, it can be + re-enabled once #220056 is implemented. In order to avoid duplicating definitions for bindings which already have unfoldings we do some minor headstands to avoid serialising the RHS of a definition if it has diff --git a/compiler/GHC/IfaceToCore.hs b/compiler/GHC/IfaceToCore.hs index fa714448ac..40cc7e34f0 100644 --- a/compiler/GHC/IfaceToCore.hs +++ b/compiler/GHC/IfaceToCore.hs @@ -933,7 +933,13 @@ tc_iface_bindings (IfaceRec bs) = do -- | See Note [Interface File with Core: Sharing RHSs] tc_iface_binding :: Id -> IfaceMaybeRhs -> IfL CoreExpr -tc_iface_binding i IfUseUnfoldingRhs = return (unfoldingTemplate $ realIdUnfolding i) +tc_iface_binding i IfUseUnfoldingRhs = + case maybeUnfoldingTemplate $ realIdUnfolding i of + Just e -> return e + Nothing -> pprPanic "tc_iface_binding" (vcat [text "Binding" <+> quotes (ppr i) <+> text "had an unfolding when the interface file was created" + , text "which has now gone missing, something has badly gone wrong." + , text "Unfolding:" <+> ppr (realIdUnfolding i)]) + tc_iface_binding _ (IfRhs rhs) = tcIfaceExpr rhs mk_top_id :: IfaceTopBndrInfo -> IfL Id |