RFR: 8310190: C2 SuperWord: AlignVector is broken, generates misaligned packs [v21]

[Christian Hagedorn]

On Wed, 6 Dec 2023 16:28:21 GMT, Emanuel Peter <epeter at openjdk.org> wrote:

>> src/hotspot/share/opto/superword.cpp line 1678:
>> 
>>> 1676:     tty->print_cr(" + scale(%d) * iv", scale);
>>> 1677:   }
>>> 1678: #endif
>> 
>> Not sure if you are planning to refactor the tracing code anyway but you might want to think about extracting any tracing code in this method to separate methods to not disrupt the readability of the code. You can derive some of the variables again (e.g. from VPointer etc.) to avoid having to pass many arguments to the tracing function.
>> 
>> It might even be cleaner if this entire method would be part of `AlignmentSolution`. Then you do not need to pass around all the information to separate tracing methods.
>
> @chhagedorn What if I make it a `AlignmentSolver` that then returns an `AlignmentSolution`?

That's even better! I like that idea.

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PR Review Comment: https://git.openjdk.org/jdk/pull/14785#discussion_r1418476498