RFR: 8341402: BigDecimal's square root optimization [v16]

[fabioromano1]

On Fri, 15 Nov 2024 13:22:32 GMT, Raffaello Giulietti <rgiulietti at openjdk.org> wrote:

>> fabioromano1 has updated the pull request incrementally with one additional commit since the last revision:
>> 
>>   Code simplification
>
> src/java.base/share/classes/java/math/BigDecimal.java line 2190:
> 
>> 2188:                     resultScale = strippedScale >> 1;
>> 2189:                 } else {
>> 2190:                     working = working.multiply(10L);
> 
> While this is correct, there's useless work that is being performed.
> 
> After the multiplication by 10, `working` cannot be an exact square, so this will fail later at L.2199.
> I wonder if this can be simplified to avoid the `multiply()` and the following `sqrtAndRemainder()` when `strippedScale` is odd.

I'm changing the code to take into account this fact.

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PR Review Comment: https://git.openjdk.org/jdk/pull/21301#discussion_r1843855833