[AArch64] Fix over-eager early-exit in load-store combiner

Fix early-exit analysis for memory operation pairing when operations are
not emitted in ascending order.

Reviewers: mcrosier, t.p.northover

Subscribers: aemerson, rengolin, llvm-commits

Differential Revision: https://reviews.llvm.org/D28251

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@291008 91177308-0d34-0410-b5e6-96231b3b80d8
2 files changed