diff options
author | akr <akr@b2dd03c8-39d4-4d8f-98ff-823fe69b080e> | 2013-07-09 15:43:48 +0000 |
---|---|---|
committer | akr <akr@b2dd03c8-39d4-4d8f-98ff-823fe69b080e> | 2013-07-09 15:43:48 +0000 |
commit | 5ec8b6e78e08dbd645a3dceaf617bb0ad5b2c373 (patch) | |
tree | fe7027d235b74361725dd7caaa016f9351e7ae64 /bignum.c | |
parent | 55cbeefb2df3a3985d96a8538ac145c35665cfd3 (diff) | |
download | ruby-5ec8b6e78e08dbd645a3dceaf617bb0ad5b2c373.tar.gz |
* bignum.c (bary_mul): x*1 is x.
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@41869 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
Diffstat (limited to 'bignum.c')
-rw-r--r-- | bignum.c | 11 |
1 files changed, 11 insertions, 0 deletions
@@ -1856,6 +1856,17 @@ bary_mul(BDIGIT *zds, size_t zl, BDIGIT *xds, size_t xl, BDIGIT *yds, size_t yl, return; } + if (xl == 1 && xds[0] == 1) { + MEMCPY(zds, yds, BDIGIT, yl); + MEMZERO(zds + yl, BDIGIT, zl - yl); + return; + } + if (yl == 1 && yds[0] == 1) { + MEMCPY(zds, xds, BDIGIT, xl); + MEMZERO(zds + xl, BDIGIT, zl - xl); + return; + } + /* normal multiplication when x is small */ if (xl < KARATSUBA_MUL_DIGITS) { normal: |