[llvm] [InlineAsm] Steal a bit to denote a register is spillable (PR #70738)

[Matthias Braun via llvm-commits]

MatzeB wrote:

> They are registers; and only registers.

I would say those operands **reference** a register. But typically multiple operands use the same registers and the act of spilling affects all operands referencing that (virtual-)register...

https://github.com/llvm/llvm-project/pull/70738