On Wed, 29 Jun 2022 02:22:02 GMT, Quan Anh Mai <d...@openjdk.org> wrote:
>> I do not follow your comment, allocation decisions purely based on LRGs >> interferences and data flow attributes attached to operands and is agnostic >> to encoding block contents. > > Your suggestion requires us having additional `TEMP dst` for the match rule. > Thanks. Yes, macro fusion is a fine microarchitectural optimization which can reduce load on entire execution pipeline and is **deterministic** for specific pair of cmp + jump instructions, you have aggregated destination's defs and its usages towards the tail which can save TEMP attribution on destination operand and may save a redundant spill only for high register pressure blocks. I am ok with existing handling. Thanks for your explanations. ------------- PR: https://git.openjdk.org/jdk/pull/9068
