On Wed, 4 Sep 2024 10:14:30 GMT, Maurizio Cimadamore <mcimadam...@openjdk.org>
wrote:
>> Per Minborg has updated the pull request incrementally with one additional
>> commit since the last revision:
>>
>> Consolidate logic in one method
>
> src/java.base/share/classes/jdk/internal/foreign/SegmentBulkOperations.java
> line 123:
>
>> 121: // This method is intended for 0 <= bytes < 7
>> 122: @ForceInline
>> 123: private static long mismatchSmall(AbstractMemorySegmentImpl src,
>> long srcOffset,
>
> Question. Isn't this:
>
>
> // 0...0X00
> if (remaining >= 4) {
> if (SCOPED_MEMORY_ACCESS.getInt(src.sessionImpl(),
> src.unsafeGetBase(), src.unsafeGetOffset() + srcFromOffset + offset) !=
> SCOPED_MEMORY_ACCESS.getInt(dst.sessionImpl(),
> dst.unsafeGetBase(), dst.unsafeGetOffset() + dstFromOffset + offset)) {
> return mismatchSmall(src, srcFromOffset + offset, dst,
> dstFromOffset + offset, offset, 4, srcAndDstBytesDiffer);
> }
> offset += 4;
> remaining -= 4;
> }
> // 0...00X0
> if (remaining >= 2) {
> if (SCOPED_MEMORY_ACCESS.getShort(src.sessionImpl(),
> src.unsafeGetBase(), src.unsafeGetOffset() + srcFromOffset + offset) !=
> SCOPED_MEMORY_ACCESS.getShort(dst.sessionImpl(),
> dst.unsafeGetBase(), dst.unsafeGetOffset() + dstFromOffset + offset)) {
> return mismatchSmall(src, srcFromOffset + offset, dst,
> dstFromOffset + offset, offset, 2, srcAndDstBytesDiffer);
> }
> offset += 2;
> remaining -= 2;
> }
> // 0...000X
> if (remaining == 1) {
> if (SCOPED_MEMORY_ACCESS.getByte(src.sessionImpl(),
> src.unsafeGetBase(), src.unsafeGetOffset() + srcFromOffset + offset) !=
> SCOPED_MEMORY_ACCESS.getByte(dst.sessionImpl(),
> dst.unsafeGetBase(), dst.unsafeGetOffset() + dstFromOffset + offset)) {
> return offset;
> }
> }
>
>
> An optimized version of "mismatchSmall" ? Can we reuse the code?
I've managed to do this now that the new optimized bit mismatch finders have
removed the need for recursion in such a method.
-------------
PR Review Comment: https://git.openjdk.org/jdk/pull/20848#discussion_r1745491738
