Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Use Arrays#mismatch for Outputs#common operations #12710

Merged
merged 3 commits into from
Oct 25, 2023
Merged

Use Arrays#mismatch for Outputs#common operations #12710

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
3 commits
Select commit Hold shift + click to select a range
1556337
use Arrays#mismatch for Outputs#common
gf2121 Oct 23, 2023
1caf93f
add CHANGES
gf2121 Oct 25, 2023
4a8544d
Merge branch 'main' into iter_common
gf2121 Oct 25, 2023
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
2 changes: 2 additions & 0 deletions lucene/CHANGES.txt
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -223,6 +223,8 @@ Optimizations
* GITHUB#12589: Disjunctions now sometimes run as conjunctions when the minimum
competitive score requires multiple clauses to match. (Adrien Grand)

* GITHUB#12710: Use Arrays#mismatch for Outputs#common operations. (Guo Feng)

Changes in runtime behavior
---------------------

Expand Down
30 changes: 16 additions & 14 deletions lucene/core/src/java/org/apache/lucene/util/fst/ByteSequenceOutputs.java
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -17,6 +17,7 @@
package org.apache.lucene.util.fst;

import java.io.IOException;
import java.util.Arrays;
import org.apache.lucene.store.DataInput;
import org.apache.lucene.store.DataOutput;
import org.apache.lucene.util.BytesRef;
Expand Down Expand Up @@ -44,28 +45,29 @@ public BytesRef common(BytesRef output1, BytesRef output2) {
assert output1 != null;
assert output2 != null;

int pos1 = output1.offset;
int pos2 = output2.offset;
int stopAt1 = pos1 + Math.min(output1.length, output2.length);
while (pos1 < stopAt1) {
if (output1.bytes[pos1] != output2.bytes[pos2]) {
break;
}
pos1++;
pos2++;
}
int mismatchPos =
Arrays.mismatch(
output1.bytes,
output1.offset,
output1.offset + output1.length,
output2.bytes,
output2.offset,
output2.offset + output2.length);

if (pos1 == output1.offset) {
if (mismatchPos == 0) {
// no common prefix
return NO_OUTPUT;
} else if (pos1 == output1.offset + output1.length) {
} else if (mismatchPos == -1) {
// exactly equals
return output1;
} else if (mismatchPos == output1.length) {
// output1 is a prefix of output2
return output1;
} else if (pos2 == output2.offset + output2.length) {
} else if (mismatchPos == output2.length) {
// output2 is a prefix of output1
return output2;
} else {
return new BytesRef(output1.bytes, output1.offset, pos1 - output1.offset);
return new BytesRef(output1.bytes, output1.offset, mismatchPos);
}
}

Expand Down
30 changes: 16 additions & 14 deletions lucene/core/src/java/org/apache/lucene/util/fst/CharSequenceOutputs.java
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -17,6 +17,7 @@
package org.apache.lucene.util.fst;

import java.io.IOException;
import java.util.Arrays;
import org.apache.lucene.store.DataInput;
import org.apache.lucene.store.DataOutput;
import org.apache.lucene.util.CharsRef;
Expand All @@ -43,28 +44,29 @@ public CharsRef common(CharsRef output1, CharsRef output2) {
assert output1 != null;
assert output2 != null;

int pos1 = output1.offset;
int pos2 = output2.offset;
int stopAt1 = pos1 + Math.min(output1.length, output2.length);
while (pos1 < stopAt1) {
if (output1.chars[pos1] != output2.chars[pos2]) {
break;
}
pos1++;
pos2++;
}
int mismatchPos =
Arrays.mismatch(
output1.chars,
output1.offset,
output1.offset + output1.length,
output2.chars,
output2.offset,
output2.offset + output2.length);

if (pos1 == output1.offset) {
if (mismatchPos == 0) {
// no common prefix
return NO_OUTPUT;
} else if (pos1 == output1.offset + output1.length) {
} else if (mismatchPos == -1) {
// exactly equals
return output1;
} else if (mismatchPos == output1.length) {
// output1 is a prefix of output2
return output1;
} else if (pos2 == output2.offset + output2.length) {
} else if (mismatchPos == output2.length) {
// output2 is a prefix of output1
return output2;
} else {
return new CharsRef(output1.chars, output1.offset, pos1 - output1.offset);
return new CharsRef(output1.chars, output1.offset, mismatchPos);
}
}

Expand Down
30 changes: 16 additions & 14 deletions lucene/core/src/java/org/apache/lucene/util/fst/IntSequenceOutputs.java
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -17,6 +17,7 @@
package org.apache.lucene.util.fst;

import java.io.IOException;
import java.util.Arrays;
import org.apache.lucene.store.DataInput;
import org.apache.lucene.store.DataOutput;
import org.apache.lucene.util.IntsRef;
Expand All @@ -43,28 +44,29 @@ public IntsRef common(IntsRef output1, IntsRef output2) {
assert output1 != null;
assert output2 != null;

int pos1 = output1.offset;
int pos2 = output2.offset;
int stopAt1 = pos1 + Math.min(output1.length, output2.length);
while (pos1 < stopAt1) {
if (output1.ints[pos1] != output2.ints[pos2]) {
break;
}
pos1++;
pos2++;
}
int mismatchPos =
Arrays.mismatch(
output1.ints,
output1.offset,
output1.offset + output1.length,
output2.ints,
output2.offset,
output2.offset + output2.length);

if (pos1 == output1.offset) {
if (mismatchPos == 0) {
// no common prefix
return NO_OUTPUT;
} else if (pos1 == output1.offset + output1.length) {
} else if (mismatchPos == -1) {
Copy link
Contributor

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Why aren't we merging these 2 branches?

else if (mismatchPos == -1 || mismatchPos == output1.length)

Copy link
Contributor Author

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Just for better comment to explain. Will merge if you think this way is better :)

Copy link
Contributor

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Either way would look good to me.

// exactly equals
return output1;
} else if (mismatchPos == output1.length) {
// output1 is a prefix of output2
return output1;
} else if (pos2 == output2.offset + output2.length) {
} else if (mismatchPos == output2.length) {
// output2 is a prefix of output1
return output2;
} else {
return new IntsRef(output1.ints, output1.offset, pos1 - output1.offset);
return new IntsRef(output1.ints, output1.offset, mismatchPos);
Copy link
Contributor

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

I had a previous comment about this length parameter, but it seems mismatchPos will return the relative index, so that's ok. Just added here for posterity.

}
}

Expand Down