[llvm] InstrProfiling.cpp: Let lowerIntrinsics() able to insert BBs. (PR #95585)

[NAKAMURA Takumi via llvm-commits]

chapuni wrote:

@ellishg Thanks for explanation of backgrounds. I've understood this preparation is no longer needed.

> If you want a conditional store, you might want to consider creating a new function and calling it. You might even be able to force it to be inlined.

I'll take this direction for now if inserting the new Function is safe here.

> If the CFG of the assembly changes, that is ok.

I think we could introduce the new mode for TATAS (Test and Test and Set) to atomicrmw. So I will write the proposal if this is reasonable. I will introduce "conditional atomicrmw OR".

https://github.com/llvm/llvm-project/pull/95585