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bc: optimize bc_parse_pushIndex()

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function                                             old     new   delta
bc_parse_pushIndex                                    80      68     -12

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
This commit is contained in:
Denys Vlasenko 2018-12-12 16:44:34 +01:00
parent 26819db9a3
commit c2da68e896
1 changed files with 14 additions and 7 deletions
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21
miscutils/bc.c
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@ -3460,16 +3460,23 @@ static void bc_parse_pushName(BcParse *p, char *name)
static void bc_parse_pushIndex(BcParse *p, size_t idx)
{
unsigned char amt, i, nums[sizeof(size_t)];
size_t mask;
unsigned amt;
///oh boy
for (amt = 0; idx; ++amt) {
nums[amt] = (char) idx;
idx = (idx & ((unsigned long) ~(UCHAR_MAX))) >> sizeof(char) * CHAR_BIT;
}
mask = ((size_t)0xff) << (sizeof(idx) * 8 - 8);
amt = sizeof(idx);
do {
if (idx & mask) break;
mask >>= 8;
amt--;
} while (amt != 0);
bc_parse_push(p, amt);
for (i = 0; i < amt; ++i) bc_parse_push(p, nums[i]);
while (idx != 0) {
bc_parse_push(p, (unsigned char)idx);
idx >>= 8;
}
}
static void bc_parse_number(BcParse *p, BcInst *prev, size_t *nexs)