Summary:
This patch adds support for the predicated integer halving add/sub
instructions:
* SHADD, UHADD, SRHADD, URHADD
* SHSUB, UHSUB, SHSUBR, UHSUBR
The specification can be found here:
https://developer.arm.com/docs/ddi0602/latest
Reviewed By: rovka
Differential Revision: https://reviews.llvm.org/D62000
llvm-svn: 361136