[GHC] #8272: testing if SpLim=$rbp and Sp=$rsp changed performance at all

[GHC]

#8272: testing if SpLim=$rbp and Sp=$rsp changed performance at all
-------------------------------------+-------------------------------------
        Reporter:  carter            |                Owner:  carter
            Type:  task              |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  7.7
      Resolution:                    |             Keywords:
                                     |  callingConvention
Operating System:  Unknown/Multiple  |         Architecture:  x86_64
 Type of failure:  Runtime           |  (amd64)
  performance bug                    |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
-------------------------------------+-------------------------------------
Changes (by bollu):

 * cc: bollu (added)


Comment:

 CCing myself in light of some [https://github.com/bollu/simplexhc-cpp
 simplexhc] experiments. On ackermann function,
 [https://gist.github.com/bgamari/bd424e82d96ddb7b9e67c5e51cdcc5ec GHC and
 clang O3 don't scale linearly].

 On teaching simplexhc to generate C-like code (using `call/ret` instead of
 custom stack frame management), I began getting C-like performance on the
 same examples. Previously, I was around GHC, or somewhat slower.
 [https://gist.github.com/bollu/a59c3c8d2c193e2d63409064b6d855c3 Link to
 numbers from that experiment here].

 I sent out an e-mail to LLVM-dev, asking if it is possible to fake GHC-
 like "custom call stack on the heap" within LLVM. If possible, I'd like to
 implement that and check for slowdowns in C code. That should provide some
 data of the benefits of choosing to use the native call stack.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/8272#comment:20>
GHC <http://www.haskell.org/ghc/>
The Glasgow Haskell Compiler