diff options
author | akr <akr@b2dd03c8-39d4-4d8f-98ff-823fe69b080e> | 2013-08-16 01:11:18 +0000 |
---|---|---|
committer | akr <akr@b2dd03c8-39d4-4d8f-98ff-823fe69b080e> | 2013-08-16 01:11:18 +0000 |
commit | dcd4832d6967dab51189382793cb0aadc7705915 (patch) | |
tree | 81227a7561b26d1d6c6628e39c76a38630832134 /bignum.c | |
parent | 9f6c62ad5f09ec1782442ec499cfd2a9962a3d2c (diff) | |
download | ruby-dcd4832d6967dab51189382793cb0aadc7705915.tar.gz |
* bignum.c (bigdivrem_single1): Renamed from bigdivrem_single. Add
x_higher_bdigit argument.
(bigdivrem_single): Just call bigdivrem_single1.
(bigdivrem_restoring): Use bigdivrem_single1 to avoid memmove.
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@42576 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
Diffstat (limited to 'bignum.c')
-rw-r--r-- | bignum.c | 20 |
1 files changed, 13 insertions, 7 deletions
@@ -2677,19 +2677,20 @@ bigdivrem_num_extra_words(size_t xn, size_t yn) } static BDIGIT -bigdivrem_single(BDIGIT *qds, const BDIGIT *xds, size_t xn, BDIGIT y) +bigdivrem_single1(BDIGIT *qds, const BDIGIT *xds, size_t xn, BDIGIT x_higher_bdigit, BDIGIT y) { assert(0 < xn); + assert(x_higher_bdigit < y); if (POW2_P(y)) { BDIGIT r; r = xds[0] & (y-1); - bary_small_rshift(qds, xds, xn, bitsize(y)-1, 0); + bary_small_rshift(qds, xds, xn, bitsize(y)-1, x_higher_bdigit); return r; } else { size_t i; BDIGIT_DBL t2; - t2 = 0; + t2 = x_higher_bdigit; i = xn; while (i--) { t2 = BIGUP(t2) + xds[i]; @@ -2700,6 +2701,12 @@ bigdivrem_single(BDIGIT *qds, const BDIGIT *xds, size_t xn, BDIGIT y) } } +static BDIGIT +bigdivrem_single(BDIGIT *qds, const BDIGIT *xds, size_t xn, BDIGIT y) +{ + return bigdivrem_single1(qds, xds, xn, 0, y); +} + static void bigdivrem_restoring(BDIGIT *zds, size_t zn, BDIGIT *yds, size_t yn) { @@ -2707,15 +2714,14 @@ bigdivrem_restoring(BDIGIT *zds, size_t zn, BDIGIT *yds, size_t yn) size_t ynzero; assert(BDIGIT_MSB(yds[yn-1])); + assert(zds[zn-1] < yds[yn-1]); for (ynzero = 0; !yds[ynzero]; ynzero++); if (ynzero+1 == yn) { BDIGIT r; - r = bigdivrem_single(zds+ynzero, zds+ynzero, zn-ynzero, yds[yn-1]); - assert(zds[zn-1] == 0); - MEMMOVE(zds+yn, zds+yn-1, BDIGIT, zn - yn); - zds[yn-1] = r; + r = bigdivrem_single1(zds+yn, zds+ynzero, zn-yn, zds[zn-1], yds[ynzero]); + zds[ynzero] = r; return; } |