8369123: Still more small Float16 refactorings

[jddarcy]

Upon further inspection, found a few more opportunities to refine the use of constants in the Float16 implementation.

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• JDK-8369123: Still more small Float16 refactorings (Enhancement - P4)

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• 01: Full - Incremental (be2b4ab8)
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[eirbjo]

// Currently Float16 is a value-based class and in future it is

in the future

// IEEEremainder / remainder operator remainder

Would one remainder suffice for this remainder reminder?

private final short value;

Consider adding a field comment to align with Float, Double and friends.

private static final Float16 ZERO = valueOf(0);

Other private implementation constants in this class have comments. These would be rather obvious, but perheps we can consider adding them just for consistency?

Should we consider ordering private vs. public constants? Now they seem a bit mingled, making it harder for the eye to scan the public API of the class.

Line 372:

return new Float16((short)(sign_bit | 0x7c00));

0x7c00 here is EXP_BIT_MASK, right?

// toHexString, line 288:
return s.replaceFirst("p-1022$", "p-14");

Are we okay to invoke regex from such low level code?

[ExE-Boss]

// IEEEremainder / remainder operator remainder

Would one remainder suffice for this remainder reminder?

IEEEremainder differs from the Java language remainder operator, due to the difference in rounding policy.

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Refs:

• https://docs.oracle.com/javase/specs/jvms/se25/html/jvms-6.html#jvms-6.5.drem
• https://docs.oracle.com/en/java/javase/25/docs/api/java.base/java/lang/Math.html#IEEEremainder(double,double)

[eirbjo]

// IEEEremainder / remainder operator remainder

IEEEremainder differs from the Java language remainder operator, due to the difference in rounding policy.

Thanks for providing context, it makes the sentence easier to understand. I now parse "remainder operator remainder" as "the remainder function as defined by JVM drem/frem bytecodes".

The comment seems a bit terse in its current form, more of a note-to-self reminder of future implementation ideas. Usually comments refer to current functionality, so this was sticking out to me as somewhat unusual. @jddarcy may have an opinion here.