zeroshade commented on code in PR #13768: URL: https://github.com/apache/arrow/pull/13768#discussion_r936849193
########## go/arrow/bitutil/bitmaps.go: ########## @@ -422,3 +423,81 @@ func CopyBitmap(src []byte, srcOffset, length int, dst []byte, dstOffset int) { dst[nbytes-1] &= ^trailMask dst[nbytes-1] |= lastData & trailMask } + +type bitOp struct { + opWord func(uint64, uint64) uint64 + opByte func(byte, byte) byte +} + +var ( + bitAndOp = bitOp{ + opWord: func(l, r uint64) uint64 { return l & r }, + opByte: func(l, r byte) byte { return l & r }, + } + bitOrOp = bitOp{ + opWord: func(l, r uint64) uint64 { return l | r }, + opByte: func(l, r byte) byte { return l | r }, + } +) + +func alignedBitmapOp(op bitOp, left, right []byte, lOffset, rOffset int64, out []byte, outOffset int64, length int64) { + debug.Assert(lOffset%8 == rOffset%8, "aligned bitmap op called with unaligned offsets") + debug.Assert(lOffset%8 == outOffset%8, "aligned bitmap op called with unaligned output offset") + + nbytes := BytesForBits(length + lOffset%8) + left = left[lOffset/8:] + right = right[rOffset/8:] + out = out[outOffset/8:] + for i := int64(0); i < nbytes; i++ { + out[i] = op.opByte(left[i], right[i]) + } +} + +func unalignedBitmapOp(op bitOp, left, right []byte, lOffset, rOffset int64, out []byte, outOffset int64, length int64) { + leftRdr := NewBitmapWordReader(left, int(lOffset), int(length)) + rightRdr := NewBitmapWordReader(right, int(rOffset), int(length)) + writer := NewBitmapWordWriter(out, int(outOffset), int(length)) + + for nwords := leftRdr.Words(); nwords > 0; nwords-- { + writer.PutNextWord(op.opWord(leftRdr.NextWord(), rightRdr.NextWord())) Review Comment: Before: ``` goos: linux goarch: amd64 pkg: github.com/apache/arrow/go/v10/arrow/bitutil cpu: 12th Gen Intel(R) Core(TM) i7-12700H BenchmarkBitmapAnd/nbytes=32768/aligned-20 25418 48190 ns/op 1359.95 MB/s 0 B/op 0 allocs/op BenchmarkBitmapAnd/nbytes=32768/unaligned-20 29241 40694 ns/op 1610.46 MB/s 192 B/op 3 allocs/op BenchmarkBitmapAnd/nbytes=131072/aligned-20 6798 194915 ns/op 1344.91 MB/s 0 B/op 0 allocs/op BenchmarkBitmapAnd/nbytes=131072/unaligned-20 7018 162163 ns/op 1616.55 MB/s 192 B/op 3 allocs/op ``` After: ``` goos: linux goarch: amd64 pkg: github.com/apache/arrow/go/v10/arrow/bitutil cpu: 12th Gen Intel(R) Core(TM) i7-12700H BenchmarkBitmapAnd/nbytes=32768/aligned-20 126613 9308 ns/op 7040.73 MB/s 0 B/op 0 allocs/op BenchmarkBitmapAnd/nbytes=32768/unaligned-20 28724 41392 ns/op 1583.30 MB/s 192 B/op 3 allocs/op BenchmarkBitmapAnd/nbytes=131072/aligned-20 32292 37420 ns/op 7005.50 MB/s 0 B/op 0 allocs/op BenchmarkBitmapAnd/nbytes=131072/unaligned-20 7068 166973 ns/op 1569.97 MB/s 192 B/op 3 allocs/op ``` -- 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. To unsubscribe, e-mail: github-unsubscr...@arrow.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org