diff options
Diffstat (limited to 'include/mcl/util.hpp')
| -rw-r--r-- | include/mcl/util.hpp | 17 |
1 files changed, 11 insertions, 6 deletions
diff --git a/include/mcl/util.hpp b/include/mcl/util.hpp index afdeaf9..0d3876d 100644 --- a/include/mcl/util.hpp +++ b/include/mcl/util.hpp @@ -196,7 +196,7 @@ void getRandVal(T *out, RG& rg, const T *in, size_t bitSize) @note &out != x and out = the unit element of G */ template<class G, class T> -void powGeneric(G& out, const G& x, const T *y, size_t n, void mul(G&, const G&, const G&) , void sqr(G&, const G&), bool constTime = false) +void powGeneric(G& out, const G& x, const T *y, size_t n, void mul(G&, const G&, const G&) , void sqr(G&, const G&), void normalize(G&, const G&), bool constTime = false) { assert(&out != &x); while (n > 0) { @@ -223,11 +223,16 @@ void powGeneric(G& out, const G& x, const T *y, size_t n, void mul(G&, const G&, } } G tbl[4]; // tbl = { discard, x, x^2, x^3 } - x.normalize(); - tbl[0] = x; - tbl[1] = x; - sqr(tbl[2], tbl[1]); tbl[2].normalize(); - mul(tbl[3], tbl[2], x); tbl[3].normalize(); + if (normalize) { + normalize(tbl[0], x); + } else { + tbl[0] = x; + } + tbl[1] = tbl[0]; + sqr(tbl[2], tbl[1]); + if (normalize) { normalize(tbl[2], tbl[2]); } + mul(tbl[3], tbl[2], x); + if (normalize) { normalize(tbl[3], tbl[3]); } T v = y[n - 1]; int m = cybozu::bsr<T>(v); if (m & 1) { |