[AArch64] Swap comparison operands if that enables some folding.
Summary:
AArch64 can fold some shift+extend operations on the RHS operand of
comparisons, so swap the operands if that makes sense.
This provides a fix for https://bugs.llvm.org/show_bug.cgi?id=38751
Reviewers: efriedma, t.p.northover, javed.absar
Subscribers: mcrosier, kristof.beyls, llvm-commits
Differential Revision: https://reviews.llvm.org/D53067
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@344439
91177308-0d34-0410-b5e6-
96231b3b80d8