Clean up sqrt logic in pcurves #4171
Merged
Conversation
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Closed
randombit
force-pushed
the
jack/fix-pcurves-sqrt
branch
from
2113369
to
77b64a6
Compare
The sqrt function returned zero to indicate a lack of a square root but this leads to uncertain situations since zero does itself have a square root. Fix point decompression to verify that the x value is a quadratic root; previously we'd accept invalid x coordinates. Remove is_square; it was only needed for SSWU and it's faster to just attempt to square root and then use the returned Choice to decide which square root to use. This improves the performance of hash to curve by almost 30%.
randombit
force-pushed
the
jack/fix-pcurves-sqrt
branch
from
77b64a6
to
6d1172c
Compare
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
The sqrt function returned zero to indicate a lack of a square root but this leads to uncertain situations since zero does itself have a square root.
Fix point decompression to verify that the x value is a quadratic root; previously we'd accept invalid x coordinates.
Remove is_square; it was only needed for SSWU and it's faster to just attempt to square root and then use the returned Choice to decide which square root to use. This improves the performance of hash to curve by almost 30%.