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cleaned up a bit, and made add_ext and sub_ext proper entry points,

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without preconditions on the arguments
This commit is contained in:
ceriel
1988-08-04 11:16:20 +00:00
parent 3d3b891371
commit 2d12b422e5
8 changed files with 122 additions and 125 deletions
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37
mach/proto/fp/add_ext.c
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@@ -14,10 +14,39 @@
add_ext(e1,e2)
register EXTEND *e1,*e2;
{
if (b64_add(&e1->m1,&e2->m1)) { /* addition carry */
b64_rsft(&e1->m1); /* shift mantissa one bit RIGHT */
e1->m1 |= 0x80000000L; /* set max bit */
e1->exp++; /* increase the exponent */
if ((e2->m1 | e2->m2) == 0L) {
return;
}
if ((e1->m1 | e1->m2) == 0L) {
*e1 = *e2;
return;
}
sft_ext(e1, e2); /* adjust mantissas to equal powers */
if (e1->sign != e2->sign) {
/* e1 + e2 = e1 - (-e2) */
if (e2->m1 > e1->m1 ||
(e2->m1 == e1->m1 && e2->m2 > e1->m2)) {
/* abs(e2) > abs(e1) */
if (e1->m2 > e2->m2) {
e2->m1 -= 1; /* carry in */
}
e2->m1 -= e1->m1;
e2->m2 -= e1->m2;
*e1 = *e2;
}
else {
if (e2->m2 > e1->m2)
e1->m1 -= 1; /* carry in */
e1->m1 -= e2->m1;
e1->m2 -= e2->m2;
}
}
else {
if (b64_add(&e1->m1,&e2->m1)) { /* addition carry */
b64_rsft(&e1->m1); /* shift mantissa one bit RIGHT */
e1->m1 |= 0x80000000L; /* set max bit */
e1->exp++; /* increase the exponent */
}
}
nrm_ext(e1);
}