[PATCH] D18732: [SystemZ] Support LRVH and STRVH opcodes

Mon Apr 4 05:20:38 PDT 2016

bryanpkc added a comment.

In http://reviews.llvm.org/D18732#391023, @uweigand wrote:

> Your change to README.txt implies that LRVH and STRVH still are not generated by the compiler.  However, the change to SystemZInstrInfo.td actually installs DAG patterns for the SelectionDAG pass to recognize, so this is somewhat confusing.

Oops, that wasn't intentional; I had only wanted to get the assembly parser working.

> Do those DAG patterns actually not match?  If so, it might be better to not provide any.  (Or of course even better, provide ones that actually work.)   Or do they in fact match, and you just didn't verify that?  If so, it would be good update README.txt accordingly and add a CodeGen test to verify correct code generation.

I think it would be better to make the codegen emit LRVH and STRVH properly. I will verify that the patterns match correctly and add some test cases. Was there a reason why README.txt explicitly stated that LRVH and STRVH were not supported?

Thanks.

http://reviews.llvm.org/D18732