[GHC] #7814: panic in PPC NCG

[GHC]

#7814: panic in PPC NCG
--------------------------------+-------------------------------------------
Reporter:  heisenbug            |          Owner:          
    Type:  bug                  |         Status:  new     
Priority:  normal               |      Component:  Compiler
 Version:  7.7                  |       Keywords:          
      Os:  Unknown/Multiple     |   Architecture:  powerpc 
 Failure:  Building GHC failed  |      Blockedby:          
Blocking:                       |        Related:          
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Comment(by heisenbug):

 Here is the CFG:
 {{{
               ___________
              /           \
 cc -> cl -> cn ===> ce -> co
     \
      cj
 }}}

 Strangely on x86 with -fPIC this decomposes to 3 SCCs OTOH on PPC -fPIC
 only one. But this probably causes the trouble, as the 'ce' label is only
 invoked via a return, and needs the picBaseReg too (actually 'co' needs
 it). So this probably the bug.

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/7814#comment:6>
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