Re: [PATCH v2 4/4] target/loongarch: flogb_{s/d} add set float_flag_divbyzero

[Richard Henderson]

On 9/26/22 23:48, Song Gao wrote:

if fj ==0 or fj == INT32_MIN/INT64_MIN, LoongArch host set fcsr cause exception 
FP_DIV0,
So we need set exception flags float_flagdivbyzero if fj ==0.

You are correct that ieee754 says that logB(0) should raise divbyzero.
This should be fixed in softfloat-parts.c.inc, not here, within

        case float_class_zero:

            /* log2(0) = -inf */

            a->cls = float_class_inf;

            a->sign = 1;

            return;



r~