On Tue, 21 Nov 2023 13:24:34 GMT, Eric Liu <e...@openjdk.org> wrote: >> Vector API defines zero-extend operations [1], which are going to be >> intrinsified and generated to `VectorUCastNode` by C2. This patch adds >> backend implementation for `VectorUCastNode` on AArch64. >> >> The micro benchmark shows significant performance improvement. In my test >> machine (SVE, 256-bit), the result is shown as below: >> >> >> >> Benchmark Before After Units Gain >> VectorZeroExtend.byte2Int 3168.251 243012.399 ops/ms 75.70 >> VectorZeroExtend.byte2Long 3212.201 216291.588 ops/ms 66.33 >> VectorZeroExtend.byte2Short 3391.968 182655.365 ops/ms 52.85 >> VectorZeroExtend.int2Long 1012.197 80448.553 ops/ms 78.48 >> VectorZeroExtend.short2Int 1812.471 153416.828 ops/ms 83.65 >> VectorZeroExtend.short2Long 1788.382 129794.814 ops/ms 71.58 >> >> >> On other Neon systems, we can get similar performance boost as a result of >> intrinsification success. >> >> Since `VectorUCastNode` only used in Vector API's zero extension currently, >> this patch also adds assertion on nodes' definitions to clarify their usages. >> >> [TEST] >> compiler/vectorapi and jdk/incubator/vector passed on NEON and SVE machines. >> >> [1] >> https://github.com/openjdk/jdk/blob/master/src/jdk.incubator.vector/share/classes/jdk/incubator/vector/VectorOperators.java#L726 > > Eric Liu has updated the pull request incrementally with one additional > commit since the last revision: > > add _sve_xunpk & remove dead code > > Change-Id: Ic19836feb8a73ea7e65443794f2a0eb1363f6e2f
src/hotspot/cpu/aarch64/assembler_aarch64.hpp line 3872: > 3870: void sve_sunpklo(FloatRegister Zd, SIMD_RegVariant T, FloatRegister > Zn) { > 3871: _sve_xunpk(/* is_unsigned */ false, /* is_high */ false, Zd, T, Zn); > 3872: } This code expansion does not look right. You should be able to make this change without so much code expansion. #define INSN(NAME, unsigned, high) void name(FloatRegister Zd, SIMD_RegVariant T, FloatRegister Zn) { \ _sve_xunpk(unsigned, high, T, Zn); \ } INSN(sve_uunpkhi, true, true) ... ------------- PR Review Comment: https://git.openjdk.org/jdk/pull/16670#discussion_r1400716627