#11731: Simplifier: Inlining trivial let can lose sharing -------------------------------------+------------------------------------- Reporter: nomeata | Owner: Type: bug | Status: patch Priority: normal | Milestone: Component: Compiler | Version: 8.1 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: | Unknown/Multiple Type of failure: None/Unknown | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Phab:D2064 Wiki Page: | -------------------------------------+------------------------------------- Comment (by simonpj):
* It would no longer get erased with `-fstrictness -fno-worker- wrapper`. Although we might argue that this is not a supported configuration.
I'm very dubious about `-no-worker-wrapper`. Maybe we should kill it off.
* Since the worker-wrapper pass happens before the next occurrence analyzer (does it?), the occurrence analyzer no longer sees the `1*` `demandInfo` and thus cannot set the `oneShotInfo`.
False. The occurrence analyser uses call-once `C1` info (the `Count` argument to `UCall`). It does not use the demanded-once `1*` info (the `Count` field to `Use`). It is the latter that we are going to erase, NOT the former.
Why not do it in the occurrence analyser?
By "it" I guess you mean the erasure? Because the occurrence analyser runs repeatedly; no sense in repeatedly erasing info that is already erased. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/11731#comment:28 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler