epotyom commented on code in PR #13625:
URL: https://github.com/apache/lucene/pull/13625#discussion_r1700906253
##########
lucene/core/src/java/org/apache/lucene/util/SparseFixedBitSet.java:
##########
@@ -337,34 +337,23 @@ private int firstDoc(int i4096, int i4096upper) {
@Override
public int nextSetBit(int i) {
- assert i < length;
- final int i4096 = i >>> 12;
- final long index = indices[i4096];
- final long[] bitArray = this.bits[i4096];
- int i64 = i >>> 6;
- int o = Long.bitCount(index & ((1L << i64) - 1));
- if ((index & (1L << i64)) != 0) {
- // There is at least one bit that is set in the current long, check if
- // one of them is after i
- final long bits = bitArray[o] >>> i; // shifts are mod 64
- if (bits != 0) {
- return i + Long.numberOfTrailingZeros(bits);
- }
- o += 1;
- }
- final long indexBits = index >>> i64 >>> 1;
- if (indexBits == 0) {
- // no more bits are set in the current block of 4096 bits, go to the
next one
- return firstDoc(i4096 + 1, indices.length);
- }
- // there are still set bits
- i64 += 1 + Long.numberOfTrailingZeros(indexBits);
- final long bits = bitArray[o];
- return (i64 << 6) | Long.numberOfTrailingZeros(bits);
+ // Override with a version that skips the bound check on the result since
we know it will not
+ // go OOB:
+ return nextSetBitInRange(i, length);
}
@Override
public int nextSetBit(int start, int upperBound) {
+ int res = nextSetBitInRange(start, upperBound);
+ return res < upperBound ? res : DocIdSetIterator.NO_MORE_DOCS;
+ }
+
+ /**
+ * Returns the next set bit in the specified range, but treats `upperBound`
as a best-effort hint
+ * rather than a hard requirement. Note that this may return a result that
is >= upperBound in
+ * some cases, so callers must add their own check if `upperBound` is a hard
requirement.
+ */
+ private int nextSetBitInRange(int start, int upperBound) {
assert start < length;
assert upperBound > start;
Review Comment:
I know it's preexisting, but maybe we can extend the assert to make
potential debugging easier?
```suggestion
assert upperBound > start && upperBound <= length : "upperBound=" +
upperBound + ", start=" + start + ", length=" + length;
```
--
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: [email protected]
For queries about this service, please contact Infrastructure at:
[email protected]
---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]
