Summary:
This patch implements custom floating-point reduction ISD nodes that
have vector results, which are used to lower the following intrinsics:
* llvm.aarch64.sve.fadda
* llvm.aarch64.sve.faddv
* llvm.aarch64.sve.fmaxv
* llvm.aarch64.sve.fmaxnmv
* llvm.aarch64.sve.fminv
* llvm.aarch64.sve.fminnmv
SVE reduction instructions keep their result within a vector register,
with all other bits set to zero.
Changes in this patch were implemented by Paul Walker and Sander de
Smalen.
Reviewers: sdesmalen, efriedma, rengolin
Reviewed By: efriedma
Differential Revision: https://reviews.llvm.org/D78723
672b62ea21