RFR: 8350563: C2 compilation fails because PhaseCCP does not reach a fixpoint [v2]

[Liam Miller-Cushon]

On Wed, 12 Mar 2025 12:14:39 GMT, Emanuel Peter <epeter at openjdk.org> wrote:

>> Liam Miller-Cushon has updated the pull request with a new target base due to a merge or a rebase. The incremental webrev excludes the unrelated changes brought in by the merge/rebase. The pull request contains six additional commits since the last revision:
>> 
>>  - copyright
>>  - style
>>  - Merge branch 'openjdk:master' into mernst/JDK-8350563
>>  - RegTest
>>  - Merge branch 'openjdk:master' into mernst/JDK-8350563
>>  - push `con->(cast*)->and` uses
>
> src/hotspot/share/opto/phaseX.cpp line 2008:
> 
>> 2006:     ((use_op == Op_LShiftI || use_op == Op_LShiftL) && use->in(2) == parent)) {
>> 2007: 
>> 2008:     auto push_and_uses_to_worklist = [&](Node* n) {
> 
> Amazing, this looks much better. I suggest you rename `new_type` -> `parent_type`, just to keep things consistent.

Done

> test/hotspot/jtreg/compiler/c2/TestAndConZeroCCP.java line 1:
> 
>> 1: /*
> 
> The test should probably be moved to `test/hotspot/jtreg/compiler/ccp/`, that would be more specific.

Done

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PR Review Comment: https://git.openjdk.org/jdk/pull/23871#discussion_r1991831170
PR Review Comment: https://git.openjdk.org/jdk/pull/23871#discussion_r1991831262