[GHC] #11162: T783 regresses severely in allocations with new pattern match checker

[GHC]

#11162: T783 regresses severely in allocations with new pattern match checker
-------------------------------------+-------------------------------------
        Reporter:  bgamari           |                Owner:
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:  8.0.1
       Component:  Compiler          |              Version:  7.10.2
      Resolution:                    |             Keywords:
                                     |  PatternMatchWarnings
Operating System:  Unknown/Multiple  |         Architecture:
 Type of failure:  Compile-time      |  Unknown/Multiple
  performance bug                    |            Test Case:  T783
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
-------------------------------------+-------------------------------------
Changes (by thomie):

 * milestone:   => 8.0.1


Comment:

 From `testsuite/tests/perf/compiler/all.T` for `T783`:
 {{{
 2015-08-28: 526230456 (amd64/Linux)
 2016-02-03: 488592288 (amd64/Linux)
 }}}

 So bytes allocated is now 7% lower than it was before the whole pattern
 match checker overhaul. Nice.

 The patch has been merged to 8.0 already in
 6e23b68047a2c995562eba173fe9485cae18bff2.

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/11162#comment:5>
GHC <http://www.haskell.org/ghc/>
The Glasgow Haskell Compiler