diff options
| author | MITSUNARI Shigeo <herumi@nifty.com> | 2018-09-16 06:16:23 +0800 |
|---|---|---|
| committer | MITSUNARI Shigeo <herumi@nifty.com> | 2018-09-16 06:16:23 +0800 |
| commit | 20a39f9eb358c9f830c9c3d0a49ec3a41baf1031 (patch) | |
| tree | 644ed3928e4cecc073ae8bc6b25e384ade6ecdae | |
| parent | 3a06b921daed4fa6cadeb185c20ad133e4db8137 (diff) | |
| download | dexon-mcl-20a39f9eb358c9f830c9c3d0a49ec3a41baf1031.tar.gz dexon-mcl-20a39f9eb358c9f830c9c3d0a49ec3a41baf1031.tar.zst dexon-mcl-20a39f9eb358c9f830c9c3d0a49ec3a41baf1031.zip | |
shortcut of twist_b for BN254
| -rw-r--r-- | include/mcl/bn.hpp | 6 |
1 files changed, 5 insertions, 1 deletions
diff --git a/include/mcl/bn.hpp b/include/mcl/bn.hpp index 2086f9a..38f3f8d 100644 --- a/include/mcl/bn.hpp +++ b/include/mcl/bn.hpp @@ -1042,7 +1042,11 @@ struct Param { if (cp.isMtype) { twist_b = Fp2(cp.b) * xi; } else { - twist_b = Fp2(cp.b) / xi; + if (cp.b == 2 && cp.xi_a == 1) { + twist_b = Fp2(1, -1); // shortcut + } else { + twist_b = Fp2(cp.b) / xi; + } } if (twist_b == Fp2(1, -1)) { twist_b_type = tb_1m1i; |