> `Vector::slice` is a method at the top-level class of the Vector API that > concatenates the 2 inputs into an intermediate composite and extracts a > window equal to the size of the inputs into the result. It is used in vector > conversion methods where the part number is not 0 to slice the parts to the > correct positions. Slicing is also used in text processing such as utf8 and > utf16 validation. x86 starting from SSSE3 has `palignr` which does vector > slicing very efficiently. As a result, I think it is beneficial to add a C2 > node for this operation as well as intrinsify `Vector::slice` method. > > A slice is currently implemented as > `v2.rearrange(iota).blend(v1.rearrange(iota), blendMask)` which requires > preparation of the index vector and the blending mask. Even with the > preparations being hoisted out of the loops, microbenchmarks show improvement > using the slice instrinsics. Some have tremendous increases in throughput due > to the limitation that a mask of length 2 cannot currently be intrinsified, > leading to falling back to the Java implementations. > > Please take a look and have some reviews. Thank you very much.
Quan Anh Mai has updated the pull request with a new target base due to a merge or a rebase. The pull request now contains ten commits: - instruction asserts - Merge branch 'master' into sliceIntrinsics - add comments explaining anonymous classes - address reviews - sse2, increase warmup - aesthetic - optimise 64B - add jmh - vector slice intrinsics ------------- Changes: https://git.openjdk.org/jdk/pull/12909/files Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=12909&range=03 Stats: 1603 lines in 58 files changed: 1277 ins; 257 del; 69 mod Patch: https://git.openjdk.org/jdk/pull/12909.diff Fetch: git fetch https://git.openjdk.org/jdk.git pull/12909/head:pull/12909 PR: https://git.openjdk.org/jdk/pull/12909
