RFR: JDK-8331859 : [PPC64] Remove support for Power7 and older [v4]

[Martin Doerr]

On Fri, 2 May 2025 12:36:56 GMT, Suchismith Roy <sroy at openjdk.org> wrote:

>> src/hotspot/cpu/ppc/ppc.ad line 10371:
>> 
>>> 10369:   ins_cost(DEFAULT_COST);
>>> 10370: 
>>> 10371:   expand %{
>> 
>> HI @TheRealMDoerr  
>> I tried removing moveD2L_reg_stack as it is the only usage in ad file. 
>> But the build fails . Any exception to this rule ?
>
> Hi @TheRealMDoerr  could you explain this ?

`moveD2L_reg_stack` is the only instruct which matches `Set dst (MoveD2L src)` where `dst` is a `stackSlotL` and `src` is a `regD`. If you remove it, C2 can't match it any more.

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

PR Review Comment: https://git.openjdk.org/jdk/pull/20262#discussion_r2071818806