[llvm] [llvm][NVPTX] Fix quadratic runtime in ProxyRegErasure (PR #105730)

[Kunwar Grover via llvm-commits]

Groverkss wrote:

> @Groverkss -- what happens when we compile the reproducer? Does it generate invalid output or is it a compiler crasher?

Oops, sorry, I should have included the failure message. The compiler crashes on an assert (I have a RelWithDebInfo build):

https://gist.github.com/Groverkss/1160f651b063df57303b4f8112435b27

https://github.com/llvm/llvm-project/pull/105730