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* bignum.c (bigdivrem_normal): Removed.

(bary_divmod_normal): New function.
  (bary_divmod): Use bary_divmod_normal.
  (bigdivrem): Use bary_divmod_normal.



git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@42832 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
This commit is contained in:
akr 2013-09-04 15:10:48 +00:00
parent 88270e7773
commit cf3736a75a
2 changed files with 85 additions and 73 deletions

View file

@ -1,3 +1,10 @@
Thu Sep 5 00:08:44 2013 Tanaka Akira <akr@fsij.org>
* bignum.c (bigdivrem_normal): Removed.
(bary_divmod_normal): New function.
(bary_divmod): Use bary_divmod_normal.
(bigdivrem): Use bary_divmod_normal.
Wed Sep 4 23:02:12 2013 Tanaka Akira <akr@fsij.org> Wed Sep 4 23:02:12 2013 Tanaka Akira <akr@fsij.org>
* bignum.c (bigdivrem): Useless declaration removed. * bignum.c (bigdivrem): Useless declaration removed.

151
bignum.c
View file

@ -2636,28 +2636,64 @@ bigdivrem_restoring(BDIGIT *zds, size_t zn, BDIGIT *yds, size_t yn)
} }
static void static void
bigdivrem_normal(BDIGIT *zds, size_t zn, const BDIGIT *xds, size_t xn, BDIGIT *yds, size_t yn, int needs_mod) bary_divmod_normal(BDIGIT *qds, size_t qn, BDIGIT *rds, size_t rn, const BDIGIT *xds, size_t xn, const BDIGIT *yds, size_t yn)
{ {
int shift; int shift;
BDIGIT *zds, *yyds;
size_t zn;
VALUE tmpz = 0;
VALUE tmpyy = 0;
assert(zn == xn + 1); assert(qds ? (xn - yn + 1) <= qn : 1);
assert(yn < xn || (xn == yn && yds[yn - 1] <= xds[xn - 1])); assert(rds ? yn <= rn : 1);
zn = xn + BIGDIVREM_EXTRA_WORDS;
shift = nlz(yds[yn-1]); shift = nlz(yds[yn-1]);
if (shift) { if (shift) {
bary_small_lshift(yds, yds, yn, shift); if (qds && zn <= qn)
zds = qds;
else
zds = ALLOCV_N(BDIGIT, tmpz, zn);
if (rds)
yyds = rds;
else
yyds = ALLOCV_N(BDIGIT, tmpyy, yn);
zds[xn] = bary_small_lshift(zds, xds, xn, shift); zds[xn] = bary_small_lshift(zds, xds, xn, shift);
bary_small_lshift(yyds, yds, yn, shift);
} }
else { else {
if (qds && zn <= qn)
zds = qds;
else
zds = ALLOCV_N(BDIGIT, tmpz, zn);
MEMCPY(zds, xds, BDIGIT, xn); MEMCPY(zds, xds, BDIGIT, xn);
zds[xn] = 0; zds[xn] = 0;
/* bigdivrem_restoring will not modify y.
* So use yds directly. */
yyds = (BDIGIT *)yds;
} }
bigdivrem_restoring(zds, zn, yds, yn); bigdivrem_restoring(zds, zn, yyds, yn);
if (needs_mod && shift) { if (rds) {
bary_small_rshift(zds, zds, yn, shift, 0); if (shift)
bary_small_rshift(rds, zds, yn, shift, 0);
else
MEMCPY(rds, zds, BDIGIT, yn);
BDIGITS_ZERO(rds+yn, rn-yn);
} }
if (qds) {
size_t j = zn - yn;
MEMMOVE(qds, zds+yn, BDIGIT, j);
BDIGITS_ZERO(qds+j, qn-j);
}
if (tmpyy)
ALLOCV_END(tmpyy);
if (tmpz)
ALLOCV_END(tmpz);
} }
static void static void
@ -2701,45 +2737,7 @@ bary_divmod(BDIGIT *qds, size_t qn, BDIGIT *rds, size_t rn, const BDIGIT *xds, s
BDIGITS_ZERO(rds+2, rn-2); BDIGITS_ZERO(rds+2, rn-2);
} }
else { else {
size_t j; bary_divmod_normal(qds, qn, rds, rn, xds, xn, yds, yn);
size_t zn;
BDIGIT *zds;
VALUE tmpz = 0;
BDIGIT *tds;
zn = xn + BIGDIVREM_EXTRA_WORDS;
if (zn <= qn)
zds = qds;
else
zds = ALLOCV_N(BDIGIT, tmpz, zn);
MEMCPY(zds, xds, BDIGIT, xn);
BDIGITS_ZERO(zds+xn, BIGDIVREM_EXTRA_WORDS);
if (BDIGIT_MSB(yds[yn-1])) {
/* bigdivrem_normal will not modify y.
* So use yds directly. */
tds = (BDIGIT *)yds;
}
else {
/* bigdivrem_normal will modify y.
* So use rds as a temporary buffer. */
MEMCPY(rds, yds, BDIGIT, yn);
tds = rds;
}
bigdivrem_normal(zds, zn, xds, xn, tds, yn, 1);
/* copy remainder */
MEMCPY(rds, zds, BDIGIT, yn);
BDIGITS_ZERO(rds+yn, rn-yn);
/* move quotient */
j = zn - yn;
MEMMOVE(qds, zds+yn, BDIGIT, j);
BDIGITS_ZERO(qds+j, qn-j);
if (tmpz)
ALLOCV_END(tmpz);
} }
} }
@ -5898,13 +5896,15 @@ rb_big_mul(VALUE x, VALUE y)
static VALUE static VALUE
bigdivrem(VALUE x, VALUE y, volatile VALUE *divp, volatile VALUE *modp) bigdivrem(VALUE x, VALUE y, volatile VALUE *divp, volatile VALUE *modp)
{ {
long xn = RBIGNUM_LEN(x), yn = RBIGNUM_LEN(y), zn; long xn = RBIGNUM_LEN(x), yn = RBIGNUM_LEN(y);
long j; VALUE z;
VALUE z, zz; BDIGIT *xds, *yds, *zds;
VALUE tmpy = 0, tmpz = 0;
BDIGIT *xds, *yds, *zds, *tds;
BDIGIT dd; BDIGIT dd;
VALUE q = Qnil, r = Qnil;
BDIGIT *qds, *rds;
long qn, rn;
yds = BDIGITS(y); yds = BDIGITS(y);
BARY_TRUNC(yds, yn); BARY_TRUNC(yds, yn);
if (yn == 0) if (yn == 0)
@ -5952,32 +5952,37 @@ bigdivrem(VALUE x, VALUE y, volatile VALUE *divp, volatile VALUE *modp)
return Qnil; return Qnil;
} }
if (BDIGIT_MSB(yds[yn-1]) == 0) { if (divp) {
/* Make yds modifiable. */ qn = xn + BIGDIVREM_EXTRA_WORDS;
tds = ALLOCV_N(BDIGIT, tmpy, yn); q = bignew(qn, RBIGNUM_SIGN(x)==RBIGNUM_SIGN(y));
MEMCPY(tds, yds, BDIGIT, yn); qds = BDIGITS(q);
yds = tds; }
else {
qn = 0;
qds = NULL;
} }
zn = xn + BIGDIVREM_EXTRA_WORDS; if (modp) {
zds = ALLOCV_N(BDIGIT, tmpz, zn); rn = yn;
bigdivrem_normal(zds, zn, xds, xn, yds, yn, modp != NULL); r = bignew(rn, RBIGNUM_SIGN(x));
rds = BDIGITS(r);
}
else {
rn = 0;
rds = NULL;
}
if (divp) { /* move quotient down in z */ bary_divmod_normal(qds, qn, rds, rn, xds, xn, yds, yn);
j = zn - yn;
BARY_TRUNC(zds+yn, j); if (divp) {
*divp = zz = bignew(j, RBIGNUM_SIGN(x)==RBIGNUM_SIGN(y)); bigtrunc(q);
MEMCPY(BDIGITS(zz), zds+yn, BDIGIT, j); *divp = q;
} }
if (modp) { /* normalize remainder */ if (modp) {
BARY_TRUNC(zds, yn); bigtrunc(r);
*modp = zz = bignew(yn, RBIGNUM_SIGN(x)); *modp = r;
MEMCPY(BDIGITS(zz), zds, BDIGIT, yn);
} }
if (tmpy)
ALLOCV_END(tmpy);
if (tmpz)
ALLOCV_END(tmpz);
return Qnil; return Qnil;
} }