RFR: 8329077: C2 SuperWord: Add MoveD2L, MoveL2D, MoveF2I, MoveI2F [v5]
Galder Zamarreño
galder at openjdk.org
Mon Aug 25 07:13:43 UTC 2025
> I've added support to vectorize `MoveD2L`, `MoveL2D`, `MoveF2I` and `MoveI2F` nodes. The implementation follows a similar pattern to what is done with conversion (`Conv*`) nodes. The tests in `TestCompatibleUseDefTypeSize` have been updated with the new expectations.
>
> Also added a JMH benchmark which measures throughput (the higher the number the better) for methods that exercise these nodes. On darwin/aarch64 it shows:
>
>
> Benchmark (seed) (size) Mode Cnt Base Patch Units Diff
> VectorBitConversion.doubleToLongBits 0 2048 thrpt 8 1168.782 1157.717 ops/ms -1%
> VectorBitConversion.doubleToRawLongBits 0 2048 thrpt 8 3999.387 7353.936 ops/ms +83%
> VectorBitConversion.floatToIntBits 0 2048 thrpt 8 1200.338 1188.206 ops/ms -1%
> VectorBitConversion.floatToRawIntBits 0 2048 thrpt 8 4058.248 14792.474 ops/ms +264%
> VectorBitConversion.intBitsToFloat 0 2048 thrpt 8 3050.313 14984.246 ops/ms +391%
> VectorBitConversion.longBitsToDouble 0 2048 thrpt 8 3022.691 7379.360 ops/ms +144%
>
>
> The improvements observed are a result of vectorization. The lack of vectorization in `doubleToLongBits` and `floatToIntBits` demonstrates that these changes do not affect their performance. These methods do not vectorize because of flow control.
>
> I've run the tier1-3 tests on linux/aarch64 and didn't observe any regressions.
Galder Zamarreño 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 22 additional commits since the last revision:
- Merge branch 'master' into topic.fp-bits-vector
- Add more IR node positive assertions
- Fix source of data for benchmarks
- Refactor benchmarks to TypeVectorOperations
- Check at the very least that auto vectorization is supported
- Avoid VectorReinterpret::implemented
- Refactor and add copyright header
- Rephrase comment
- Removed unnecessary assert methods
- Adjust IR test after adding Move* vector support
- ... and 12 more: https://git.openjdk.org/jdk/compare/88efdd03...e7e4d801
-------------
Changes:
- all: https://git.openjdk.org/jdk/pull/26457/files
- new: https://git.openjdk.org/jdk/pull/26457/files/01fd5ba0..e7e4d801
Webrevs:
- full: https://webrevs.openjdk.org/?repo=jdk&pr=26457&range=04
- incr: https://webrevs.openjdk.org/?repo=jdk&pr=26457&range=03-04
Stats: 58306 lines in 1513 files changed: 32401 ins; 19557 del; 6348 mod
Patch: https://git.openjdk.org/jdk/pull/26457.diff
Fetch: git fetch https://git.openjdk.org/jdk.git pull/26457/head:pull/26457
PR: https://git.openjdk.org/jdk/pull/26457
More information about the hotspot-compiler-dev
mailing list