RFR: 7944: Reduce allocations of Double during chunk loading [v2]

[Henrik Dafgård]

On Thu, 27 Oct 2022 13:58:11 GMT, Richard Startin <duke at openjdk.org> wrote:

>> Using jmc-common as a library in a backend process we see high allocation rates of `Double` and have observed moderate performance improvements from this simple refactoring:
>> * Use primitive `double` in `ImpreciseScaleFactor`
>> * Use primitive `double` in `IScalarAffineTransformation.getOffset`
>> * Push multiplication of a scale factor down to a new method `ScaleFactor.scale(long multiplier)`
>> * Push `ScalarQuantity.in` down to `LongStored`/`DoubleStored` to avoid generalising over primitive types, when the `IQuantity` type can be varied instead.
>> ---------
>> ### Progress
>> - [ ] Commit message must refer to an issue
>> - [ ] Change must be properly reviewed (1 review required, with at least 1 [Committer](https://openjdk.org/bylaws#committer))
>> 
>> ### Reviewing
>> <details><summary>Using <code>git</code></summary>
>> 
>> Checkout this PR locally: \
>> `$ git fetch https://git.openjdk.org/jmc pull/436/head:pull/436` \
>> `$ git checkout pull/436`
>> 
>> Update a local copy of the PR: \
>> `$ git checkout pull/436` \
>> `$ git pull https://git.openjdk.org/jmc pull/436/head`
>> 
>> </details>
>> <details><summary>Using Skara CLI tools</summary>
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>> Checkout this PR locally: \
>> `$ git pr checkout 436`
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>> View PR using the GUI difftool: \
>> `$ git pr show -t 436`
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>> </details>
>> <details><summary>Using diff file</summary>
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>> Download this PR as a diff file: \
>> <a href="https://git.openjdk.org/jmc/pull/436.diff">https://git.openjdk.org/jmc/pull/436.diff</a>
>> 
>> </details>
>
> Richard Startin has updated the pull request with a new target base due to a merge or a rebase. The pull request now contains one commit:
> 
>   JMC-7944: Reduce allocations of Double during chunk loading

Marked as reviewed by hdafgard (Reviewer).

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PR: https://git.openjdk.org/jmc/pull/436