motorhead/qemu
1
0
Fork 0
mirror of https://github.com/Motorhead1991/qemu.git synced 2025-08-06 09:13:55 -06:00
Code Issues Projects Releases Packages Wiki Activity Actions

ppc: Implement bcdsr. instruction

Browse source 
bcdsr.: Decimal shift and round. This instruction works like bcds.
however, when performing right shift, 1 will be added to the
result if the last digit was >= 5.

Signed-off-by: Jose Ricardo Ziviani <joserz@linux.vnet.ibm.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
This commit is contained in:
Jose Ricardo Ziviani 2017-01-10 00:10:12 -02:00 • committed by David Gibson
parent a49a95e9e4
commit a54238adac
4 changed files with 52 additions and 0 deletions
Download patch file Download diff file Expand all files Collapse all files

48
target/ppc/int_helper.c
View file

@ -3143,6 +3143,54 @@ uint32_t helper_bcdus(ppc_avr_t *r, ppc_avr_t *a, ppc_avr_t *b, uint32_t ps)
return cr;
}
uint32_t helper_bcdsr(ppc_avr_t *r, ppc_avr_t *a, ppc_avr_t *b, uint32_t ps)
{
int cr;
int unused = 0;
int invalid = 0;
bool ox_flag = false;
int sgnb = bcd_get_sgn(b);
ppc_avr_t ret = *b;
ret.u64[LO_IDX] &= ~0xf;
#if defined(HOST_WORDS_BIGENDIAN)
int i = a->s8[7];
ppc_avr_t bcd_one = { .u64 = { 0, 0x10 } };
#else
int i = a->s8[8];
ppc_avr_t bcd_one = { .u64 = { 0x10, 0 } };
#endif
if (bcd_is_valid(b) == false) {
return CRF_SO;
}
if (unlikely(i > 31)) {
i = 31;
} else if (unlikely(i < -31)) {
i = -31;
}
if (i > 0) {
ulshift(&ret.u64[LO_IDX], &ret.u64[HI_IDX], i * 4, &ox_flag);
} else {
urshift(&ret.u64[LO_IDX], &ret.u64[HI_IDX], -i * 4);
if (bcd_get_digit(&ret, 0, &invalid) >= 5) {
bcd_add_mag(&ret, &ret, &bcd_one, &invalid, &unused);
}
}
bcd_put_digit(&ret, bcd_preferred_sgn(sgnb, ps), 0);
cr = bcd_cmp_zero(&ret);
if (ox_flag) {
cr |= CRF_SO;
}
*r = ret;
return cr;
}
void helper_vsbox(ppc_avr_t *r, ppc_avr_t *a)
{
int i;