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Remove unused virtuals from ABISysV_ppc*
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Authored by brucem on Oct 7 2015, 3:25 AM.

Details

Summary

The StackUsesFrames and FunctionCallsChangeCFA virtual functions
aren't used anywhere and aren't overridden by anything.

They were introduced when the ABISysV_ppc* code was added and weren't
used at the time. The review for the commit that added them can be
found at http://reviews.llvm.org/D5988

The commit comment notes that backtraces don't yet work:

Backtraces don't work. This is due to PowerPC ABI using a
backchain pointer in memory, instead of a dedicated frame
pointer register for the backchain.

So there is a possibility these were added with the intent of using
them in the future.

Diff Detail

Repository
rL LLVM

Event Timeline

brucem updated this revision to Diff 36726.Oct 7 2015, 3:25 AM
brucem retitled this revision from to Remove unused virtuals from ABISysV_ppc*.
brucem updated this object.
brucem added reviewers: clayborg, jingham, jhibbits, emaste.
brucem added a subscriber: lldb-commits.
jhibbits edited edge metadata.Oct 7 2015, 7:14 AM

Backtraces do work now, for ppc at least (ppc64 IIRC still has issues dealing with the function descriptors, but traversing the backchain does work). I can test this after I get my system set up from my move, but if you've tested it either natively or on a core then I'll greenlight it.

brucem added a comment.Oct 7 2015, 7:19 AM

There's nothing to test here short of "Does it compile?" as these functions aren't actually used anywhere. I'm cleaning out dead virtuals in various patches.

jhibbits accepted this revision.Oct 7 2015, 7:34 AM
jhibbits edited edge metadata.

There's nothing to test here short of "Does it compile?" as these functions aren't actually used anywhere. I'm cleaning out dead virtuals in various patches.

Ah okay. I think when I added this ABI plugin, those came along for the ride when I copied the SysV-x86_64 plugin, I don't remember adding these myself, so they must be just plain old leftovers.

This revision is now accepted and ready to land.Oct 7 2015, 7:34 AM
clayborg accepted this revision.Oct 7 2015, 9:28 AM
clayborg edited edge metadata.
emaste accepted this revision.Oct 7 2015, 9:31 AM
emaste edited edge metadata.
This revision was automatically updated to reflect the committed changes.