[llvm] [AArch64][SME] Reuse ZT0 spill slot (PR #158593)

[Sander de Smalen via llvm-commits]

sdesmalen-arm wrote:

> > I had hoped the stack slot coloring would have removed the unnecessary slots, but that doesn't seem to happen (and would need a bit of work to support). Anyway, this LGTM
> 
> IIRC, the stack slot coloring depends on the lifetime markers (`LIFETIME_START/END`)

That's true for the StackColoring pass, but I thought the StackSlotColoring pass was able to do the same for spill slots without the markers.

https://github.com/llvm/llvm-project/pull/158593