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

bn: fix Red#imod #178

Merged
merged 3 commits into from
Jun 6, 2018
Merged

bn: fix Red#imod #178

Show file tree
Hide file tree
Changes from 2 commits
Commits
Show all changes
3 commits
Select commit Hold shift + click to select a range
5125c8b
bn: fix Red#imod
fanatid Feb 16, 2018
b75f6c1
bn: add method move
fanatid Mar 9, 2018
81593be
bn: rename BN#move to BN#_move
fanatid Jun 6, 2018
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
11 changes: 10 additions & 1 deletion lib/bn.js
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -327,6 +327,13 @@
dest.red = this.red;
};

BN.prototype.move = function move (dest) {
Copy link
Owner

Choose a reason for hiding this comment

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

Oh, shouldn't it be private? It looks like this could lead to funny state issues if used as a part of API.

Copy link
Collaborator Author

Choose a reason for hiding this comment

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

I'll not mind of making it private. Do you want see it as separate function or as "inline" function?

Copy link
Owner

Choose a reason for hiding this comment

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

IMO, it makes sense to have it on a prototype. Just prefix it with _. @dcousens what do you think?

Copy link
Contributor

@dcousens dcousens Mar 10, 2018 •
edited
Loading

Choose a reason for hiding this comment

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

@indutny I think the public interface semantics of move can be assumed that the originating object is reset or garbage after use.
I think it is fine to have on the public interface; however, I don't mind either way.

Copy link
Contributor

Choose a reason for hiding this comment

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

@fanatid prefix it with _?

Copy link
Collaborator Author

Choose a reason for hiding this comment

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

@dcousens added prefix _, let me know if I should squash commits

dest.words = this.words;
dest.length = this.length;
dest.negative = this.negative;
dest.red = this.red;
};

BN.prototype.clone = function clone () {
var r = new BN(null);
this.copy(r);
Expand Down Expand Up @@ -3169,7 +3176,9 @@

Red.prototype.imod = function imod (a) {
if (this.prime) return this.prime.ireduce(a)._forceRed(this);
return a.umod(this.m)._forceRed(this);

a.umod(this.m)._forceRed(this).move(a);
return a;
};

Red.prototype.neg = function neg (a) {
Expand Down
9 changes: 9 additions & 0 deletions test/red-test.js
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -262,4 +262,13 @@ describe('BN.js/Reduction context', function () {
red.prime.split(input, output);
assert.equal(input.cmp(output), 0);
});

it('imod should change host object', function () {
Copy link
Contributor

@dcousens dcousens Mar 9, 2018 •
edited
Loading

Choose a reason for hiding this comment

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

maybe indicate (via redIMul)

var red = BN.red(new BN(13));
var a = new BN(2).toRed(red);
var b = new BN(7).toRed(red);
var c = a.redIMul(b);
assert.equal(a.toNumber(), 1);
assert.equal(c.toNumber(), 1);
});
});