zeroshade commented on a change in pull request #9671: URL: https://github.com/apache/arrow/pull/9671#discussion_r595201726
########## File path: go/parquet/internal/bmi/_lib/bitmap_bmi2.c ########## @@ -0,0 +1,38 @@ +// Licensed to the Apache Software Foundation (ASF) under one +// or more contributor license agreements. See the NOTICE file +// distributed with this work for additional information +// regarding copyright ownership. The ASF licenses this file +// to you under the Apache License, Version 2.0 (the +// "License"); you may not use this file except in compliance +// with the License. You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +#include <stdint.h> +#include <x86intrin.h> + +void extract_bits(uint64_t bitmap, uint64_t select_bitmap, uint64_t* res) { + *res = _pext_u64(bitmap, select_bitmap); +} + +void popcount64(uint64_t bitmap, uint64_t* res) { Review comment: So i gave my replies to the top level comment but completely forgot to reply to the actual question here: The reason why we drop to C and generate the assembly / convert to Go plan9 assembly here is to be able to take advantage of SIMD intrinsics like AVX2/SSE4 etc. which are not currently accessible natively in Go. This is a technique that was actually used by @sbinet in the Go Arrow module and he published some articles on it. That all said, for single values like this, I think I might be able to safely have it return the value instead of using res as output, I'll check it. ---------------------------------------------------------------- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. For queries about this service, please contact Infrastructure at: us...@infra.apache.org
