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mruby-bigint (mpz_and): simplify the code

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This commit is contained in:
Yukihiro "Matz" Matsumoto
2024-07-26 22:29:04 +09:00
parent bf081c3d3d
commit dea1cc18a6
1 changed files with 14 additions and 40 deletions
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mrbgems/mruby-bigint/core/bigint.c
+14 -40
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@@ -890,6 +890,8 @@ mpz_2comp(mrb_state *mrb, mpz_t *x)
}
}
#define make_2comp(v,c) do { v=~(v)+(c); c=((v)==0 && (c));} while (0)
void
mpz_and(mrb_state *mrb, mpz_t *z, mpz_t *x, mpz_t *y)
{
@@ -899,49 +901,21 @@ mpz_and(mrb_state *mrb, mpz_t *z, mpz_t *x, mpz_t *y)
}
mrb_assert(x->sz > 0 || y->sz > 0);
z->sn = x->sn < 0 && y->sn < 0 ? -1 : 1;
size_t max_sz = (x->sz > y->sz) ? x->sz : y->sz;
mpz_realloc(mrb, z, max_sz);
z->sn = (x->sn == y->sn) ? x->sn : 1;
mpz_t xx, yy;
if (x->sn < 0) {
mpz_init_set(mrb, &xx, x);
x = &xx;
mpz_2comp(mrb, x);
}
if (y->sn < 0) {
mpz_init_set(mrb, &yy, y);
y = &yy;
mpz_2comp(mrb, y);
}
char c1 = 1, c2 = 1, c3 = 1;
for (size_t i = 0; i < max_sz; i++) {
uint32_t xv = (i < x->sz) ? x->p[i] : 0;
uint32_t yv = (i < y->sz) ? y->p[i] : 0;
uint32_t *ds1, *ds2, *zds;
size_t l1, l2;
short sign;
if (x->sz > y->sz) {
l1 = y->sz;
l2 = x->sz;
ds1 = y->p;
ds2 = x->p;
sign = y->sn;
if (x->sn < 0) make_2comp(xv, c1);
if (y->sn < 0) make_2comp(yv, c2);
uint32_t zv = xv & yv;
if (z->sn < 0) make_2comp(zv, c3);
z->p[i] = zv;
}
else {
l1 = x->sz;
l2 = y->sz;
ds1 = x->p;
ds2 = y->p;
sign =x->sn;
}
mpz_realloc(mrb, z, l2);
zds = z->p;
size_t i;
for (i=0; i<l1; i++) {
zds[i] = ds1[i] & ds2[i];
}
for (; i<l2; i++) {
zds[i] = sign>0?0:ds2[i];
}
if (z->sn < 0) mpz_2comp(mrb, z);
}
static void