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

14 Jan 2013

      #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    
--------------------------------+-------------------------------------------
 Using LLVM 3.2 (release,) or LLVM 3.3svn, on my Mac OS X 10.8 machine, the
 stage1 compiler fails to compile ```PrimOps.cmm``` with this error:

 {{{
 $ make
 ===--- building phase 0
 make -r --no-print-directory -f ghc.mk phase=0 phase_0_builds
 make[1]: Nothing to be done for `phase_0_builds'.
 ===--- building phase 1
 make -r --no-print-directory -f ghc.mk phase=1 phase_1_builds
 make[1]: Nothing to be done for `phase_1_builds'.
 ===--- building final phase
 make -r --no-print-directory -f ghc.mk phase=final all
 "inplace/bin/ghc-stage1" -static -optc-DDEBUG  -H64m -O0 -fllvm -Iincludes
 -Iincludes/dist -Iincludes/dist-derivedconstants/header -Iincludes/dist-
 ghcconstants/header -Irts -Irts/dist/build -DCOMPILING_RTS -package-name
 rts  -dcmm-lint  -DDTRACE     -i -irts -irts/dist/build
 -irts/dist/build/autogen -Irts/dist/build -Irts/dist/build/autogen
 -O0    -c rts/PrimOps.cmm -o rts/dist/build/PrimOps.debug_o
 /usr/local/bin/opt:
 /var/folders/f6/rjtvxfp92j3ffvm3zs7hv7vh0000gn/T/ghc99887_0/ghc99887_0.ll:6800:17:
 error: invalid cast opcode for cast from 'i64' to 'i64'
   %ln1N5 = zext i64 1 to i64
 }}}

 This seems to occur inside ```stg_retryzh```, which looks like:

 {{{
 ==================== LLVM Code ====================
 define  cc 10 void @stg_retryzh(i64* noalias nocapture %Base_Arg, i64*
 noalias nocapture %Sp_Arg, i64* noalias nocapture %Hp_Arg, i64 %R1_Arg,
 i64 %R2_Arg, i64 %R3_Arg, i64 %R4_Arg, i64 %R5_Arg, i64 %R6_Arg, i64
 %SpLim_Arg) align 8 nounwind
 {
 {
   ...
   ...
 ccD:
   ...
   %ln1MS = call ccc i8* (i8*,i8*)* @stmStartTransaction( i8* %ln1MP, i8*
 %ln1MR ) nounwind
   %ln1MT = ptrtoint i8* %ln1MS to i64
   store i64 %ln1MT, i64* %lccV
   %ln1MU = load i64** %Base_Var
   %ln1MV = getelementptr inbounds i64* %ln1MU, i32 25
   %ln1MW = bitcast i64* %ln1MV to i64*
   %ln1MX = load i64* %ln1MW, !tbaa !4
   %ln1MY = add i64 %ln1MX, 8
   %ln1MZ = add i64 %ln1MY, 72
   %ln1N0 = load i64* %lccV
   %ln1N1 = inttoptr i64 %ln1MZ to i64*
   store i64 %ln1N0, i64* %ln1N1, !tbaa !5
   %ln1N2 = load i64* %lccU
   %ln1N3 = add i64 %ln1N2, 8
   %ln1N4 = add i64 %ln1N3, 0
   %ln1N5 = zext i64 1 to i64                <------ Invalid
   %ln1N6 = inttoptr i64 %ln1N4 to i64*
   store i64 %ln1N5, i64* %ln1N6, !tbaa !5
   %ln1N7 = load i64* %lccU
   %ln1N8 = add i64 %ln1N7, 8
   %ln1N9 = add i64 %ln1N8, 16
   %ln1Na = inttoptr i64 %ln1N9 to i64*
   %ln1Nb = load i64* %ln1Na, !tbaa !5
   store i64 %ln1Nb, i64* %R1_Var
   %ln1Nc = load i64** %Base_Var
   %ln1Nd = load i64** %Sp_Var
   %ln1Ne = load i64** %Hp_Var
   %ln1Nf = load i64* %R1_Var
   %ln1Ng = load i64* %SpLim_Var
   tail call cc 10 void (i64*,i64*,i64*,i64,i64,i64,i64,i64,i64,i64)*
 @stg_ap_v_fast( i64* %ln1Nc, i64* %ln1Nd, i64* %ln1Ne, i64 %ln1Nf, i64
 undef, i
   ret void
   ...
   ...
 }}}

 Which would seem to correspond to this in ```PrimOps.cmm```:

 {{{
 stg_retryzh /* no arg list: explicit stack layout */
 {
   W_ frame_type;
   W_ frame;
   W_ trec;
   W_ outer;
   W_ r;
   ...
   ...
   (r) = ccall stmWait(MyCapability() "ptr", CurrentTSO "ptr", trec "ptr");
   if (r != 0) {
     ...
     ...
   } else {
     // Transaction was not valid: retry immediately
     ("ptr" trec) = ccall stmStartTransaction(MyCapability() "ptr", outer
 "ptr");
     StgTSO_trec(CurrentTSO) = trec;
     Sp = frame;
     R1 = StgAtomicallyFrame_code(frame);
     jump stg_ap_v_fast [R1];
   }
 }
 }}}

 I'm still investigating. I think this is related to #7571 and #7575.

-- 
Ticket URL: http://hackage.haskell.org/trac/ghc/ticket/7580
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