[GHC] #13379: Space leak / quadratic behavior when inlining
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Fri Apr 28 11:04:10 UTC 2017
#13379: Space leak / quadratic behavior when inlining
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Reporter: jberryman | Owner: (none)
Type: bug | Status: new
Priority: normal | Milestone:
Component: Compiler | Version: 8.0.1
Resolution: | Keywords: Inlining
Operating System: Unknown/Multiple | Architecture:
Type of failure: Compile-time | Unknown/Multiple
performance bug | Test Case:
Blocked By: | Blocking:
Related Tickets: #13586 | Differential Rev(s):
Wiki Page: |
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Comment (by Simon Peyton Jones <simonpj@…>):
In [changeset:"29d88ee173bc9b04245a33d5268dda032f5dc331/ghc"
29d88ee1/ghc]:
{{{
#!CommitTicketReference repository="ghc"
revision="29d88ee173bc9b04245a33d5268dda032f5dc331"
Be a bit more eager to inline in a strict context
If we see f (g x), and f is strict, we want to be a bit more eager to
inline g, because it may well expose an eval (on x perhaps) that can
be eliminated or shared.
I saw this in nofib boyer2, function RewriteFuns.onewayunify1. It
showed up as a consequence of the preceding patch that makes the
simplifier do less work (Trac #13379). We had
f d (g x)
where f was a class-op. Previously we simplified both d and
(g x) with a RuleArgCtxt (making g a bit more eager to inline).
But now we simplify only d that way, then fire the rule, and
only then simplify (g x). Firing the rule produces a strict
funciion, so we want to make a strict function encourage
inlining a bit.
}}}
--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/13379#comment:18>
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