llvm dev - Sep 2016 - [PowerPC] Recent branch too far breakage

I'm using a recent revision of TOT (280704) to build clang/LLVM for 
PowerPC64 little endian. I'm getting an assembler error when building 
PPCInstPrinter.cpp:

The error is:

/tmp/PPCInstPrinter-84c835.s: Assembler messages:
/tmp/PPCInstPrinter-84c835.s:7671: Error: operand out of range 
(0x0000000000008004 is not between 0xffffffffffff8000 and 
0x0000000000007ffc)

The offending line is the bne branch in this snippet:

.LBB24_787:
         ld 3, 16(29)
         ld 4, 24(29)
         sub      4, 4, 3
         rldicl 4, 4, 60, 4
         cmplwi 0, 4, 3
         bne      0, .LBB24_2630

Could this be because of a recent change in the PowerPC code generator 
or just because PPCInstPrinter.cpp changed a bit and exposed a 
pre-existing bug?


-Rich

Hi Rich,

It is hard to tell, but there was a bug fix made to the branch relaxation code;
perhaps the fix was not bug free -- Could this have been caused by r280626?

 -Hal

----- Original Message -----
> From: "Richard Pennington via llvm-dev" <llvm-dev at
lists.llvm.org>
> To: llvm-dev at lists.llvm.org
> Sent: Wednesday, September 7, 2016 7:29:25 AM
> Subject: [llvm-dev] [PowerPC] Recent branch too far breakage
> 
> I'm using a recent revision of TOT (280704) to build clang/LLVM for
> PowerPC64 little endian. I'm getting an assembler error when building
> PPCInstPrinter.cpp:
> 
> The error is:
> 
> /tmp/PPCInstPrinter-84c835.s: Assembler messages:
> /tmp/PPCInstPrinter-84c835.s:7671: Error: operand out of range
> (0x0000000000008004 is not between 0xffffffffffff8000 and
> 0x0000000000007ffc)
> 
> The offending line is the bne branch in this snippet:
> 
> .LBB24_787:
>          ld 3, 16(29)
>          ld 4, 24(29)
>          sub      4, 4, 3
>          rldicl 4, 4, 60, 4
>          cmplwi 0, 4, 3
>          bne      0, .LBB24_2630
> 
> Could this be because of a recent change in the PowerPC code
> generator
> or just because PPCInstPrinter.cpp changed a bit and exposed a
> pre-existing bug?
> 
> 
> -Rich
> 
> _______________________________________________
> LLVM Developers mailing list
> llvm-dev at lists.llvm.org
> http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev
>

----- Original Message -----
> From: "Hal Finkel via llvm-dev" <llvm-dev at
lists.llvm.org>
> To: "Richard Pennington" <rich at pennware.com>
> Cc: llvm-dev at lists.llvm.org
> Sent: Wednesday, September 7, 2016 7:37:50 AM
> Subject: Re: [llvm-dev] [PowerPC] Recent branch too far breakage
> 
> Hi Rich,
> 
> It is hard to tell, but there was a bug fix made to the branch
> relaxation code; perhaps the fix was not bug free -- Could this have
> been caused by r280626?
Is this a release or a debug build?

 -Hal
> 
>  -Hal
> 
> ----- Original Message -----
> > From: "Richard Pennington via llvm-dev" <llvm-dev at
lists.llvm.org>
> > To: llvm-dev at lists.llvm.org
> > Sent: Wednesday, September 7, 2016 7:29:25 AM
> > Subject: [llvm-dev] [PowerPC] Recent branch too far breakage
> > 
> > I'm using a recent revision of TOT (280704) to build clang/LLVM
for
> > PowerPC64 little endian. I'm getting an assembler error when
> > building
> > PPCInstPrinter.cpp:
> > 
> > The error is:
> > 
> > /tmp/PPCInstPrinter-84c835.s: Assembler messages:
> > /tmp/PPCInstPrinter-84c835.s:7671: Error: operand out of range
> > (0x0000000000008004 is not between 0xffffffffffff8000 and
> > 0x0000000000007ffc)
> > 
> > The offending line is the bne branch in this snippet:
> > 
> > .LBB24_787:
> >          ld 3, 16(29)
> >          ld 4, 24(29)
> >          sub      4, 4, 3
> >          rldicl 4, 4, 60, 4
> >          cmplwi 0, 4, 3
> >          bne      0, .LBB24_2630
> > 
> > Could this be because of a recent change in the PowerPC code
> > generator
> > or just because PPCInstPrinter.cpp changed a bit and exposed a
> > pre-existing bug?
> > 
> > 
> > -Rich
> > 
> > _______________________________________________
> > LLVM Developers mailing list
> > llvm-dev at lists.llvm.org
> > http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev
> > 
> _______________________________________________
> LLVM Developers mailing list
> llvm-dev at lists.llvm.org
> http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev
> 
-- 
Hal Finkel
Assistant Computational Scientist
Leadership Computing Facility
Argonne National Laboratory