diff options
Diffstat (limited to 'lib/mpi/mpi-cmp.c')
| -rw-r--r-- | lib/mpi/mpi-cmp.c | 46 |
1 files changed, 36 insertions, 10 deletions
diff --git a/lib/mpi/mpi-cmp.c b/lib/mpi/mpi-cmp.c index d25e9e96c310..c4cfa3ff0581 100644 --- a/lib/mpi/mpi-cmp.c +++ b/lib/mpi/mpi-cmp.c @@ -41,28 +41,54 @@ int mpi_cmp_ui(MPI u, unsigned long v) } EXPORT_SYMBOL_GPL(mpi_cmp_ui); -int mpi_cmp(MPI u, MPI v) +static int do_mpi_cmp(MPI u, MPI v, int absmode) { - mpi_size_t usize, vsize; + mpi_size_t usize; + mpi_size_t vsize; + int usign; + int vsign; int cmp; mpi_normalize(u); mpi_normalize(v); + usize = u->nlimbs; vsize = v->nlimbs; - if (!u->sign && v->sign) + usign = absmode ? 0 : u->sign; + vsign = absmode ? 0 : v->sign; + + /* Compare sign bits. */ + + if (!usign && vsign) return 1; - if (u->sign && !v->sign) + if (usign && !vsign) return -1; - if (usize != vsize && !u->sign && !v->sign) + + /* U and V are either both positive or both negative. */ + + if (usize != vsize && !usign && !vsign) return usize - vsize; - if (usize != vsize && u->sign && v->sign) - return vsize - usize; + if (usize != vsize && usign && vsign) + return vsize + usize; if (!usize) return 0; cmp = mpihelp_cmp(u->d, v->d, usize); - if (u->sign) - return -cmp; - return cmp; + if (!cmp) + return 0; + if ((cmp < 0?1:0) == (usign?1:0)) + return 1; + + return -1; +} + +int mpi_cmp(MPI u, MPI v) +{ + return do_mpi_cmp(u, v, 0); } EXPORT_SYMBOL_GPL(mpi_cmp); + +int mpi_cmpabs(MPI u, MPI v) +{ + return do_mpi_cmp(u, v, 1); +} +EXPORT_SYMBOL_GPL(mpi_cmpabs); |