[AArch64] Do not abort if overflow check does not use EQ or NE.

As suggested by Eli Friedman, instead of aborting if an overflow check
uses something other than SETEQ or SETNE, simply do not apply the
optimization.

Differential Revision: https://reviews.llvm.org/D39147

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@319837 91177308-0d34-0410-b5e6-96231b3b80d8
1 file changed