This patch extends the current functionality of the AArch64 redundant copy elimination pass to handle non-zero cases such as:
BB#0: cmp x0, #1 b.eq .LBB0_1 .LBB0_1: orr x0, xzr, #0x1 ; <-- redundant copy; x0 known to hold #1.
This removes redundant copies from most of the SPEC200X tests. When running on Kryo, I saw a 2.7% and 1% improvement in spec2000/gap and spec2006/povray, respectively. All other testing was within noise.