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

Reply via email to