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bc: code shrink in bc_num_cmp()

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function                                             old     new   delta
bc_num_cmp                                           275     231     -44

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
This commit is contained in:
Denys Vlasenko 2018-12-12 11:51:32 +01:00
parent 16494f557f
commit 251fbb57be
1 changed files with 12 additions and 14 deletions
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26
miscutils/bc.c
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@ -1601,46 +1601,44 @@ static ssize_t bc_num_cmp(BcNum *a, BcNum *b)
{ {
size_t i, min, a_int, b_int, diff; size_t i, min, a_int, b_int, diff;
BcDig *max_num, *min_num; BcDig *max_num, *min_num;
bool a_max, neg = false; bool a_max, neg;
ssize_t cmp; ssize_t cmp;
if (a == b) return 0; if (a == b) return 0;
if (a->len == 0) return BC_NUM_NEG(!!b->len, !b->neg); if (a->len == 0) return BC_NUM_NEG(!!b->len, !b->neg);
if (b->len == 0) return BC_NUM_NEG(1, a->neg); if (b->len == 0) return BC_NUM_NEG(1, a->neg);
if (a->neg) {
if (b->neg) if (a->neg != b->neg) // signs of a and b differ
neg = true; // +a,-b = a>b = 1 or -a,+b = a<b = -1
else return (int)b->neg - (int)a->neg;
return -1; neg = a->neg; // 1 if both negative, 0 if both positive
}
else if (b->neg)
return 1;
a_int = BC_NUM_INT(a); a_int = BC_NUM_INT(a);
b_int = BC_NUM_INT(b); b_int = BC_NUM_INT(b);
a_int -= b_int; a_int -= b_int;
a_max = (a->rdx > b->rdx);
if (a_int != 0) return (ssize_t) a_int; if (a_int != 0) return (ssize_t) a_int;
a_max = (a->rdx > b->rdx);
if (a_max) { if (a_max) {
min = b->rdx; min = b->rdx;
diff = a->rdx - b->rdx; diff = a->rdx - b->rdx;
max_num = a->num + diff; max_num = a->num + diff;
min_num = b->num; min_num = b->num;
} // neg = (a_max == neg); - NOP (maps 1->1 and 0->0)
else { } else {
min = a->rdx; min = a->rdx;
diff = b->rdx - a->rdx; diff = b->rdx - a->rdx;
max_num = b->num + diff; max_num = b->num + diff;
min_num = a->num; min_num = a->num;
neg = !neg; // same as "neg = (a_max == neg)"
} }
cmp = bc_num_compare(max_num, min_num, b_int + min); cmp = bc_num_compare(max_num, min_num, b_int + min);
if (cmp != 0) return BC_NUM_NEG(cmp, (!a_max) != neg); if (cmp != 0) return BC_NUM_NEG(cmp, neg);
for (max_num -= diff, i = diff - 1; i < diff; --i) { for (max_num -= diff, i = diff - 1; i < diff; --i) {
if (max_num[i]) return BC_NUM_NEG(1, (!a_max) != neg); if (max_num[i]) return BC_NUM_NEG(1, neg);
} }
return 0; return 0;