On Mon, 19 Sep 2022 08:51:24 GMT, Xiaohong Gong <xg...@openjdk.org> wrote:
> "`VectorSupport.indexVector()`" is used to compute a vector that contains the > index values based on a given vector and a scale value (`i.e. index = vec + > iota * scale`). This function is widely used in other APIs like > "`VectorMask.indexInRange`" which is useful to the tail loop vectorization. > And it can be easily implemented with the vector instructions. > > This patch adds the vector intrinsic implementation of it. The steps are: > > 1) Load the const "iota" vector. > > We extend the "`vector_iota_indices`" stubs from byte to other integral > types. For floating point vectors, it needs an additional vector cast to get > the right iota values. > > 2) Compute indexes with "`vec + iota * scale`" > > Here is the performance result to the new added micro benchmark on ARM NEON: > > Benchmark Gain > IndexVectorBenchmark.byteIndexVector 1.477 > IndexVectorBenchmark.doubleIndexVector 5.031 > IndexVectorBenchmark.floatIndexVector 5.342 > IndexVectorBenchmark.intIndexVector 5.529 > IndexVectorBenchmark.longIndexVector 3.177 > IndexVectorBenchmark.shortIndexVector 5.841 > > > Please help to review and share the feedback! Thanks in advance! This pull request has now been integrated. Changeset: 857b0f9b Author: Xiaohong Gong <xg...@openjdk.org> URL: https://git.openjdk.org/jdk/commit/857b0f9b05bc711f3282a0da85fcff131fffab91 Stats: 391 lines in 14 files changed: 361 ins; 9 del; 21 mod 8293409: [vectorapi] Intrinsify VectorSupport.indexVector Reviewed-by: eliu, jbhateja ------------- PR: https://git.openjdk.org/jdk/pull/10332
