When the instruction has imm form and fed by LI, we can remove the redundat LI instruction.
Below is an example:
renamable $x5 = LI8 2 renamable $x4 = exact SRD killed renamable $x4, killed renamable $r5, implicit $x5
will be converted to:
renamable $x5 = LI8 2 renamable $x4 = exact RLDICL killed renamable $x4, 62, 2, implicit killed $x5
But when we do this optimization, we forget to remove implicit killed $x5
This bug has caused a lnt case error. This patch is to fix above bug.