RFR: 8349523: Unused runtime calls to drem/frem should be removed [v8]

[Marc Chevalier]

On Mon, 3 Mar 2025 07:01:49 GMT, Tobias Hartmann <thartmann at openjdk.org> wrote:

>> Marc Chevalier has updated the pull request incrementally with one additional commit since the last revision:
>> 
>>   address comments
>
> src/hotspot/share/opto/divnode.cpp line 1520:
> 
>> 1518:   PhaseIterGVN* igvn = phase->is_IterGVN();
>> 1519: 
>> 1520:   bool result_is_ignored = proj_out_or_null(TypeFunc::Parms) == nullptr;
> 
> I think `result_is_unused` might be better wording (same below).

No strong opinion. Done.

> src/hotspot/share/opto/node.cpp line 2948:
> 
>> 2946: // `maybe_pure_function` is assumed to be the input of `this`. This is a bit redundant,
>> 2947: // but we already have and need maybe_pure_function in all the call sites, so
>> 2948: // it makes obvious that the `maybe_pure_function` is the same node as in the caller,
> 
> Suggestion:
> 
> // it makes it obvious that the `maybe_pure_function` is the same node as in the caller,

Done.

> src/hotspot/share/opto/node.cpp line 2952:
> 
>> 2950: // the local in the caller.
>> 2951: bool Node::is_data_proj_of_pure_function(const Node* maybe_pure_function) const {
>> 2952:   return Opcode() == Op_Proj && static_cast<const ProjNode*>(this)->_con == TypeFunc::Parms && maybe_pure_function->is_pure_function();
> 
> You should use `as_Proj()` here instead of the static cast.

Alright! Done.

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

PR Review Comment: https://git.openjdk.org/jdk/pull/23694#discussion_r1977008639
PR Review Comment: https://git.openjdk.org/jdk/pull/23694#discussion_r1977009207
PR Review Comment: https://git.openjdk.org/jdk/pull/23694#discussion_r1977009610