RFR: 8343829: Unify decimal and hexadecimal parsing in FloatingDecimal [v3]

[Raffaello Giulietti]

On Sun, 15 Dec 2024 21:57:12 GMT, j3graham <duke at openjdk.org> wrote:

>> Raffaello Giulietti 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 five additional commits since the last revision:
>> 
>>  - Merge branch 'master' into 8343829
>>  - Minors in comments.
>>  - Removed repeated comment.
>>  - Refactoring some code and comments.
>>  - 8343829: Unify decimal and hexadecimal parsing in FloatingDecimal
>
> src/java.base/share/classes/jdk/internal/math/FloatingDecimal.java line 2354:
> 
>> 2352: 
>> 2353:     /* The precision of the format. */
>> 2354:     private static final int[] P = {
> 
> What about organizing these constants as as a record - something like this:
> 
> 
> record FloatFmt(int ix, int p, int epMin, int epMax, int w, int eMin, int eMax, int qMin, int hexCount) {
> 
>     public static final FloatFmt BINARY_16 = build(0, 11, -8, 6);
>     public static final FloatFmt BINARY_32 = build(1, 24, -46, 40);
>     public static final FloatFmt BINARY_64 = build(2, 53, -324, 310);
>     public static final FloatFmt BINARY_128 = build(3, 113, -4_966, 4934);
>     public static final FloatFmt BINARY_256 = build(4, 237, -78_985, 78_915);
> 
>     private static FloatFmt build(int ix, int p, int epMin, int epMax) {
>         int w = (1 << 4 + ix) - p;
>         int eMin = (-1 << w - 1) + 2;
>         int eMax = (1 << w - 1) - 1;
>         int qMin = eMin - p + 1;
>         int hexCount = p / 4 + 2;
> 
>         return new FloatFmt(ix, p, epMin, epMax, w, eMin, eMax, qMin, hexCount);
>     }
> }
> 
> 
> 
> Methods could then be parameterized with the static instances rather than integers. I believe these values would inline well as constants.

Thanks for the suggestion @j3graham.
I'll consider it for the next commits.

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

PR Review Comment: https://git.openjdk.org/jdk/pull/22737#discussion_r1886395018