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mruby-bigint (mrb_bint_2comp): inline mpz_2comp

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This commit is contained in:
Yukihiro "Matz" Matsumoto
2024-07-27 17:43:05 +09:00
parent c218894af9
commit 811637e99f
1 changed files with 14 additions and 26 deletions
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mrbgems/mruby-bigint/core/bigint.c
+14 -26
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@@ -868,28 +868,6 @@ mpz_neg(mrb_state *mrb, mpz_t *x, mpz_t *y)
x->sn = -(y->sn);
}
static void
mpz_2comp(mrb_state *mrb, mpz_t *x)
{
size_t i = x->sz;
uint32_t *ds = x->p;
uint64_t num;
if (!i) return;
while (i--) ds[i] = ~ds[i];
i = 0; num = 1;
do {
num += ds[i];
ds[i++] = LOW(num);
num >>= DIG_SIZE;
} while (i < x->sz);
if (num != 0) {
mpz_realloc(mrb, x, x->sz + 1);
ds = x->p;
ds[x->sz-1] = x->sn > 0 ? ~0 : 1;
}
}
#define make_2comp(v,c) do { v=~(v)+(c); c=((v)==0 && (c));} while (0)
void
@@ -1705,12 +1683,22 @@ mrb_bint_hash(mrb_state *mrb, mrb_value x)
mrb_value
mrb_bint_2comp(mrb_state *mrb, mrb_value x)
{
mrb_assert(x->sn < 0);
struct RBigint *b = RBIGINT(x);
struct RBigint *b2 = bint_new(mrb);
mpz_set(mrb, &b2->mp, &b->mp);
mpz_2comp(mrb, &b2->mp);
b2->mp.sn = 1;
size_t size = b->mp.sz;
mpz_t *z = &b2->mp;
mpz_realloc(mrb, z, size);
mp_limb *ds = b->mp.p;
mp_limb *dd = z->p;
char carry = 1;
for (size_t i=0; i<size; i++) {
mp_limb xv = ds[i];
make_2comp(xv, carry);
dd[i] = xv;
}
z->sn = 1;
return mrb_obj_value(b2);
}