[GHC] #7580: Building PrimOps.cmm on OS X with LLVM 3.2 fails

[GHC]

#7580: Building PrimOps.cmm on OS X with LLVM 3.2 fails
--------------------------------+-------------------------------------------
Reporter:  thoughtpolice        |          Owner:                  
    Type:  bug                  |         Status:  new             
Priority:  normal               |      Component:  Compiler (LLVM) 
 Version:  7.7                  |       Keywords:                  
      Os:  MacOS X              |   Architecture:  Unknown/Multiple
 Failure:  Building GHC failed  |      Blockedby:                  
Blocking:                       |        Related:  #7571, #7575    
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Comment(by thoughtpolice):

 The CMM produced for ```PrimOps.cmm` in this case looks like this:

 {{{
 stg_retryzh() //  []
          { info_tbl: []
            stack_info: arg_space: 0 updfr_space: Nothing
          }
      {offset
        ...
        ...
        ccg:
            (_ccl::I64) = call "ccall" ... stmStartTransaction(BaseReg -
 24, _ccm::I64);
            I64[CurrentTSO + 8 + 72] = _ccl::I64;
            Sp = _cck::I64;
            R1 = I64[_cck::I64 + 8 + 0];
            call stg_ap_v_fast(R1) args: 8, res: 0, upd: 8;
      }
 }}}

 So it looks like the store to `Sp` is introducing the zero-extended one &
 store, but I'm still looking as to why.

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/7580#comment:1>
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