0acabc80d0
The copy/spill/fill instructions will be used by the register allocator for splitting live ranges. The copy instruction is also useful when rewriting values: If a primary value is rewritten as a secondary result, a copy instruction can be used instead: a = foo x => t, vx1 = call ... a = copy vx1 Since a primary value must be the first value of an instruction, this doesn't work: a = foo x => t, a = call ...