[PATCH] Bitcode: Add bitcode format compatibility test

[Vedant Kumar]

I've updated the patch with Sean's feedback in mind (and Duncan's input).

This version of the patch includes a 3.6-compatible IR and a corresponding bitcode blob generated by llvm-3.6.2. The bitcode blob generated by llvm-trunk is gone now.

I'm happy to report that llvm-trunk can parse the 3.6.2 bitcode without issue. When 3.7 is officially released, we can add a 3.7 bitcode blob and start working on compatibility-3.8.ll.

Could someone look over this patch and commit it if it looks good?

vedant

-------------- next part --------------
A non-text attachment was scrubbed...
Name: bccompat-submit.patch
Type: application/octet-stream
Size: 102787 bytes
Desc: not available
URL: <http://lists.llvm.org/pipermail/llvm-commits/attachments/20150730/58845027/attachment.obj>
-------------- next part --------------



> On Jul 29, 2015, at 10:44 AM, Vedant Kumar <vsk at apple.com> wrote:
> 
> 
>> Absolutely. The primary thing I can think of that could slip through this approach easily are changes that only have a manifestation at the bitcode level, not in IR. E.g. how operand indices in the bitcode were changed from absolute indices in the function to being relative to the instruction's position. Maybe also add BitCodeFormat.rst to your list of files to diff?
> 
> I've added this to my checklist.
> 
> I wanted to send a ping out on this, since Hans is planning on doing RC2 soon. It'd be nice to have this before the final release candidate.
> 
> IIRC David was concerned about duplicate tests -- I can work on cleaning that up.
> 
> vedant