[GHC] #9308: nofib fannkuch-redux runs perpetually with -fllvm

[GHC]

#9308: nofib fannkuch-redux runs perpetually with -fllvm
-------------------------------------+-------------------------------------
        Reporter:  jrp               |                   Owner:
            Type:  bug               |                  Status:  new
        Priority:  normal            |               Milestone:
       Component:  Compiler (LLVM)   |                 Version:  7.8.3
      Resolution:                    |                Keywords:  fannkuch-
                                     |  redux
Operating System:  Unknown/Multiple  |            Architecture:  x86_64
                                     |  (amd64)
 Type of failure:  Incorrect result  |               Test Case:  fannkuch-
  at runtime                         |  redux
      Blocked By:  9504              |                Blocking:
 Related Tickets:  #5567             |  Differential Revisions:
-------------------------------------+-------------------------------------
Description changed by bgamari:

Old description:

> Running the nofib benchmarks with make -k EXTRA_HC_OPTS=-fllvm on a HEAD
> build of ghc configured with perf-llvm (3.4.2) results in fannkuch-redux
> running in an infinite loop.  The benchmark runs in about 3.5s without
> the -fllvm
>

> {{{
> HC = /Users/xx/Projects/ghc/inplace/bin/ghc-stage2
> HC_OPTS = -O2 -Rghc-timing -H32m -hisuf hi -fllvm -rtsopts -XBangPatterns
> -O2
> RUNTEST_OPTS = -ghc-timing
> ==nofib== fannkuch-redux: time to compile Main follows...
> /Users/jrp/Projects/ghc/inplace/bin/ghc-stage2 -O2 -Rghc-timing -H32m
> -hisuf hi -fllvm -rtsopts -XBangPatterns -O2 -c Main.hs -o Main.o
> <<ghc: 358716248 bytes, 313 GCs, 10827462/27497216 avg/max bytes
> residency (6 samples), 57M in use, 0.00 INIT (0.00 elapsed), 0.20 MUT
> (0.53 elapsed), 0.21 GC (0.23 elapsed) :ghc>>
> ==nofib== fannkuch-redux: size of Main.o follows...
> __TEXT  __DATA  __OBJC  others  dec     hex
> 10333   497     0       0       10830   2a4e
> ==nofib== fannkuch-redux: time to link fannkuch-redux follows...
> <<ghc: 19914544 bytes, 16 GCs, 1005021/2239600 avg/max bytes residency (3
> samples), 25M in use, 0.00 INIT (0.00 elapsed), 0.01 MUT (0.53 elapsed),
> 0.02 GC (0.02 elapsed) :ghc>>
> ==nofib== fannkuch-redux: size of fannkuch-redux follows...
> __TEXT  __DATA  __OBJC  others  dec     hex
> 4075520 446464  0       4295945496      4300467480      10053ed18
> ==nofib== fannkuch-redux: time to run fannkuch-redux follows...
> ../../runstdtest/runstdtest ./fannkuch-redux  -o1 fannkuch-redux.stdout
> -o1 fannkuch-redux.stdout  -ghc-timing     11;
> ../../runstdtest/runstdtest ./fannkuch-redux  -o1 fannkuch-redux.stdout
> -o1 fannkuch-redux.stdout  -ghc-timing     11;
> ../../runstdtest/runstdtest ./fannkuch-redux  -o1 fannkuch-redux.stdout
> -o1 fannkuch-redux.stdout  -ghc-timing     11;
> ../../runstdtest/runstdtest ./fannkuch-redux  -o1 fannkuch-redux.stdout
> -o1 fannkuch-redux.stdout  -ghc-timing     11;
> ../../runstdtest/runstdtest ./fannkuch-redux  -o1 fannkuch-redux.stdout
> -o1 fannkuch-redux.stdout  -ghc-timing     11;
> }}}

New description:

 Running the nofib benchmarks with `make -k EXTRA_HC_OPTS=-fllvm` on a HEAD
 build of ghc configured with perf-llvm (3.4.2) results in fannkuch-redux
 running in an infinite loop.  The benchmark runs in about 3.5s without the
 -fllvm


 {{{
 HC = /Users/xx/Projects/ghc/inplace/bin/ghc-stage2
 HC_OPTS = -O2 -Rghc-timing -H32m -hisuf hi -fllvm -rtsopts -XBangPatterns
 -O2
 RUNTEST_OPTS = -ghc-timing
 ==nofib== fannkuch-redux: time to compile Main follows...
 /Users/jrp/Projects/ghc/inplace/bin/ghc-stage2 -O2 -Rghc-timing -H32m
 -hisuf hi -fllvm -rtsopts -XBangPatterns -O2 -c Main.hs -o Main.o
 <<ghc: 358716248 bytes, 313 GCs, 10827462/27497216 avg/max bytes residency
 (6 samples), 57M in use, 0.00 INIT (0.00 elapsed), 0.20 MUT (0.53
 elapsed), 0.21 GC (0.23 elapsed) :ghc>>
 ==nofib== fannkuch-redux: size of Main.o follows...
 __TEXT  __DATA  __OBJC  others  dec     hex
 10333   497     0       0       10830   2a4e
 ==nofib== fannkuch-redux: time to link fannkuch-redux follows...
 <<ghc: 19914544 bytes, 16 GCs, 1005021/2239600 avg/max bytes residency (3
 samples), 25M in use, 0.00 INIT (0.00 elapsed), 0.01 MUT (0.53 elapsed),
 0.02 GC (0.02 elapsed) :ghc>>
 ==nofib== fannkuch-redux: size of fannkuch-redux follows...
 __TEXT  __DATA  __OBJC  others  dec     hex
 4075520 446464  0       4295945496      4300467480      10053ed18
 ==nofib== fannkuch-redux: time to run fannkuch-redux follows...
 ../../runstdtest/runstdtest ./fannkuch-redux  -o1 fannkuch-redux.stdout
 -o1 fannkuch-redux.stdout  -ghc-timing     11;
 ../../runstdtest/runstdtest ./fannkuch-redux  -o1 fannkuch-redux.stdout
 -o1 fannkuch-redux.stdout  -ghc-timing     11;
 ../../runstdtest/runstdtest ./fannkuch-redux  -o1 fannkuch-redux.stdout
 -o1 fannkuch-redux.stdout  -ghc-timing     11;
 ../../runstdtest/runstdtest ./fannkuch-redux  -o1 fannkuch-redux.stdout
 -o1 fannkuch-redux.stdout  -ghc-timing     11;
 ../../runstdtest/runstdtest ./fannkuch-redux  -o1 fannkuch-redux.stdout
 -o1 fannkuch-redux.stdout  -ghc-timing     11;
 }}}

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/9308#comment:6>
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