RFR: 8282204: Use lea instructions for arithmetic operations on x86_64 [v7]

[Jie Fu]

On Tue, 1 Mar 2022 02:28:00 GMT, Quan Anh Mai <duke at openjdk.java.net> wrote:

>> Hi,
>> 
>> This patch adds several matching rules for x86_64 backend to use `lea` instructions for several fused arithmetic operations. Also, `lea`s don't kill flags and allow different `dst` and `src`, so it is preferred over `sll` if possible, too. 
>> 
>> Thank you very much.
>
> Quan Anh Mai has updated the pull request incrementally with one additional commit since the last revision:
> 
>   remove irrelevent changes

test/micro/org/openjdk/bench/vm/compiler/LeaInstruction.java line 32:

> 30: @BenchmarkMode(Mode.AverageTime)
> 31: @OutputTimeUnit(TimeUnit.NANOSECONDS)
> 32: @Fork(value = 2, jvmArgsAppend = {"-XX:LoopUnrollLimit=1"})

How about `value = 1`?
I think it would reduce the micro-bench testing time, right?

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

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