RFR: 8282204: Use lea instructions for arithmetic operations on x86_64 [v8]

Fri Mar 4 05:09:09 UTC 2022

On Wed, 2 Mar 2022 14:41:18 GMT, Jie Fu <jiefu at openjdk.org> wrote:

>> Quan Anh Mai has updated the pull request incrementally with one additional commit since the last revision:
>> 
>>   address reviews
>
> src/hotspot/cpu/x86/x86_64.ad line 7446:
> 
>> 7444: %}
>> 7445: 
>> 7446: instruct leaI_rReg_immI(rRegI dst, rRegI src0, immI src1)
> 
> I'm not sure if there would be any unexpected side-effect caused by the removal of `leaI_rReg_immI`.
> Why you said it seems never be matched?

The rule happens after `addI_rReg_imm` and has higher cost. I perceive it is there to define the peephole rule down below

https://github.com/openjdk/jdk/blob/b6c35ae44aeb31deb7a15ee2939156ed00b3df52/src/hotspot/cpu/x86/x86_64.ad#L13284

-------------

PR: https://git.openjdk.java.net/jdk/pull/7560