[llvm] [BOLT][AArch64] Enabling Inlining for Memcpy for AArch64 in BOLT (PR #154929)

[Sjoerd Meijer via llvm-commits]

sjoerdmeijer wrote:

Thanks for fixing that. I have created this example:

https://godbolt.org/z/rnaYKarfe

What you see there is that X9 is saved to the stack before the call to memcpy, and after the call it is reloaded because it is used by function `use`. It's a caller-saved register, and that means that if we now start using X9 as a temp register for the inlined memcpy, we are good.

Can you add this test-case to your positive tests please? You can keep the other little examples that you have, but I think it would be good to have a bigger test case where you match the whole assembly sequence that includes this caller-saved register behaviour. It would be good if you then add one more, that similarly test the whole sequence but using the FP temp register, that would then cover everything I think. 

https://github.com/llvm/llvm-project/pull/154929