[PATCH] D96351: [AIX] Enable the default AltiVec ABI on AIX

[Zarko Todorovski via Phabricator via llvm-commits]

ZarkoCA marked 2 inline comments as done.
ZarkoCA added inline comments.


================
Comment at: llvm/lib/Target/PowerPC/PPCISelLowering.cpp:15165-15166
+    if (R.first >= (PPC::V0 + 20) && R.second == &PPC::VSRCRegClass)
+      errs() << "warning: vector registers 20 to 32 are reserved in the "
+                "default AIX AltiVec ABI and cannot be used\n";
+  }
----------------
hubert.reinterpretcast wrote:
> ZarkoCA wrote:
> > hubert.reinterpretcast wrote:
> > > Is there a lot of precedent for "raw output" to stderr for warnings from the back-end? Can we diagnose this closer to where `err_asm_unknown_register_name` is handled in the front-end?
> > I've seen some cases in other targets but, no, there is not a lot of precedent for this in  PPC subtarget. 
> > 
> > I investigated with making the suggested change where `err_asm_unknown_register_name` is handled in clang but it seems to me making the changes there is at least a patch of its own.  I wasn't able to find an efficient way to do it for now using that method.  
> > 
> > If you feel strongly about this, I could remove the warning here and then make a follow on patch to add the warning the front end. My own feeling is that the warning should come from the frond end and this is a comprise for now.
> I think having something here for now is better than having nothing. Please add a FIXME comment to implement the warning in the front-end to replace this one (and do the follow up patch after dealing with the functional issues on your plate for vector support right now).
> 
> Also, can you point me to the test for this?
Thanks Hubert, I added a FIXME and the test case for the warning message. 


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D96351/new/

https://reviews.llvm.org/D96351