Previously CCMP/FCCMP instructions were only used by the
AArch64ConditionalCompares pass for control flow. This patch uses them
for SELECT like instructions as well by matching patterns in ISelLowering.
PR20927, rdar://18326194
Differential Revision: http://reviews.llvm.org/D8232
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@238793 91177308-0d34-0410-b5e6-96231b3b80d8