[LLVMdev] RFC: PowerPC tail call optimization patch

[Arnold Schwaighofer]

The patch is in
http://lists.cs.uiuc.edu/pipermail/llvm-commits/Week-of-Mon-20080421/061548.html
.

Okay to commit :)

On Thu, Apr 24, 2008 at 7:35 PM, Arnold Schwaighofer
<arnold.schwaighofer at gmail.com> wrote:
> Another round :)
>
>  I'll post the patch to llvm-commits cause i guess people might get
>  annoyed by my series of patches :).
>
>  On Tue, Apr 22, 2008 at 10:34 PM, Evan Cheng <evan.cheng at apple.com> wrote:
>  .
>  >> +PPCTargetLowering::IsEligibleForTailCallOptimization(SDOperand Call,
>  >> ...
>
> > That's fine. Please break it into two parts and move the target
>  > independent part out.
>  Done - see CheckTailCallReturnConstraints() in TargetLowering. The
>  rest of the function is still target dependent. PowerPC currently can
>  not tail call optimize byval functions, no pic/got code for non-local
>  calls. On x86 no support for pic/got code on x86-64 for non-local
>  calls.
>
>
>  >  I am not sure. Just thinking aloud. It would be nice if all of the
>  >  common code can be handled by SelectionDAGISel.  For example, it seems
>  >  possible for SDIsel to determine which operands can be overwritten and
>  >  issued the copies there?
>  >
>  >
>  Yes the common code between x86/ppc could be moved to
>  SelectionDAGISel. See CheckDAGForTailCallsAndFixThem().
>
> > There seem to be quite a bit of duplicated code. Can you refactor?
>  Created LowerMemOpCallTo.
>
>  -arnold
>