On Mon, 9 Jan 2023 09:22:25 GMT, Per Minborg <pminb...@openjdk.org> wrote:
>> Currently, `java.io.Bits` is using explicit logic to read/write various >> primitive types to/from byte arrays. Switching to the use of `VarHandle` >> access would provide better performance and less code. >> >> Also, using a standard API for these conversions means future `VarHandle` >> improvements will benefit `Bits` too. >> >> Improvements in `Bits` will propagate to `ObjectInputStream`, >> `ObjectOutputStream` and `RandomAccessFile`. >> >> Initial benchmarks and performance discussions can be found here: >> https://github.com/openjdk/panama-foreign/pull/762 > > Per Minborg has updated the pull request incrementally with one additional > commit since the last revision: > > Remove faulty test tag, improve other test tag, fix comments src/java.base/share/classes/java/io/Bits.java line 77: > 75: // Using Double.longBitsToDouble collapses NaN values to a single > 76: // "canonical" NaN value > 77: return Double.longBitsToDouble((long) LONG.get(b, off)); For the records, I believe the template classes for byte array var handle already perform this conversion - e.g. @ForceInline static $type$ get(VarHandle ob, Object oba, int index) { ArrayHandle handle = (ArrayHandle)ob; byte[] ba = (byte[]) oba; #if[floatingPoint] $rawType$ rawValue = UNSAFE.get$RawType$Unaligned( ba, ((long) index(ba, index)) + Unsafe.ARRAY_BYTE_BASE_OFFSET, handle.be); return $Type$.$rawType$BitsTo$Type$(rawValue); // <----------------------------- #else[floatingPoint] return UNSAFE.get$Type$Unaligned( ba, ((long) index(ba, index)) + Unsafe.ARRAY_BYTE_BASE_OFFSET, handle.be); #end[floatingPoint] } ```` ------------- PR: https://git.openjdk.org/jdk/pull/11840
