[llvm] [AArch64][ISel] Enable profile-aware branch condition merging (PR #201486)

[Ricardo Jesus via llvm-commits]

rj-jesus wrote:

Thank you for the analysis!

> The fix I am considering is to keep AArch64 branch-condition merging enabled in general, but avoid this loaded-compare case when both sides of the merge are integer compares depending on loaded operands. That makes the heuristic more conservative for the pattern where the current cost model cannot see the register-pressure cost, while preserving the existing ccmp opportunities for non-loaded compares. (cc: @davemgreen - let me know what you think)

Let me know if you'd like help with any testing. :)

https://github.com/llvm/llvm-project/pull/201486