[PATCH] 32-bit PowerPC ELF Position Independent Code

[Justin Hibbits]

Hi Hal,

Thanks for looking at this.  Got another one for you now.

On Wed, 16 Jul 2014 22:20:59 -0500
Hal Finkel <hfinkel at anl.gov> wrote:

> Hi Justin,
> 
> Thanks for working on this!
> 
> As Bill said, we need test cases. In addition, a few comments:
> 
> +  const MCExpr *tocExpr =
> MCBinaryExpr::CreateAdd(MCSymbolRefExpr::Create(CurrentPos,
> OutContext),
> 
> +
> MCConstantExpr::Create(0x8000, OutContext),
> 
> +                                                  OutContext);
> 
> what is 0x8000? Please provide a comment.
> 
>        BuildMI(FirstMBB, MBBI, dl, TII.get(PPC::MFLR), GlobalBaseReg);
> 
> +      if (PPCSubTarget->isTargetELF()) {
> 
> +        unsigned TempReg =
> RegInfo->createVirtualRegister(&PPC::GPRCRegClass);
> 
> +        BuildMI(FirstMBB, MBBI, dl, TII.get(PPC::GetGBRO),
> TempReg).addReg(GlobalBaseReg);
> 
> +        BuildMI(FirstMBB, MBBI, dl,
> TII.get(PPC::UpdateGBR)).addReg(GlobalBaseReg).addReg(TempReg);
> 
> +        MF->getInfo<PPCFunctionInfo>()->setUsesPICBase(true);
> 
> It is okay here for TempReg to be R0?
> 
>          // automatically synthesizes these stubs.
> 
> -        OpFlags = PPCII::MO_DARWIN_STUB;
> 
> +        OpFlags = PPCII::MO_PLT_STUB;
> 
> is this going to break Darwin?
> 
>        // unless we're building with the leopard linker or later,
> which
> 
>        // automatically synthesizes these stubs.
> 
> -      OpFlags = PPCII::MO_DARWIN_STUB;
> 
> +      OpFlags = PPCII::MO_PLT_STUB;
> 
> this too? Darwin breaking?
> 
> -  explicit PPCFunctionInfo(MachineFunction &MF) 
> +  explicit PPCFunctionInfo(MachineFunction &MFC) 
> ...
> +      MF(MFC),
> 
> This is unnecessary; because of the way that C++ name lookup works,
> MF(MF) will be fine here.
> 
> Thanks again,
> Hal

I think I've addressed all your comments in my latest patch.  Mind
giving it another look?

- Justin
-------------- next part --------------
A non-text attachment was scrubbed...
Name: ppc32pic_jul17.diff
Type: text/x-patch
Size: 35027 bytes
Desc: not available
URL: <http://lists.llvm.org/pipermail/llvm-commits/attachments/20140717/19d5b59b/attachment.bin>