From: Yasmin Beatriz <[email protected]> When the result of bcdsub is equal to zero, the result sign may be set to negative in some cases, and this does not follow the Power ISA specifications as to decimal integer arithmetic instructions.
Signed-off-by: Yasmin Beatriz <[email protected]> Signed-off-by: David Gibson <[email protected]> --- target/ppc/int_helper.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/target/ppc/int_helper.c b/target/ppc/int_helper.c index d52338ed71..ac7f92d7ae 100644 --- a/target/ppc/int_helper.c +++ b/target/ppc/int_helper.c @@ -2747,6 +2747,9 @@ uint32_t helper_bcdadd(ppc_avr_t *r, ppc_avr_t *a, ppc_avr_t *b, uint32_t ps) result.u8[BCD_DIG_BYTE(0)] = bcd_preferred_sgn(sgna, ps); zero = bcd_sub_mag(&result, a, b, &invalid, &overflow); cr = (sgna > 0) ? CRF_GT : CRF_LT; + } else if (bcd_cmp_mag(a, b) == 0) { + result.u8[BCD_DIG_BYTE(0)] = bcd_preferred_sgn(0, ps); + zero = bcd_sub_mag(&result, b, a, &invalid, &overflow); } else { result.u8[BCD_DIG_BYTE(0)] = bcd_preferred_sgn(sgnb, ps); zero = bcd_sub_mag(&result, b, a, &invalid, &overflow); -- 2.17.1
