Notice the conflict between saturation and rebias_overflow, which should never happen. Otherwise, saturate to INT32_MAX and allow the usual overflow to max, infinity, or dnan.
Signed-off-by: Richard Henderson <[email protected]> --- fpu/softfloat-parts.c.inc | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) diff --git a/fpu/softfloat-parts.c.inc b/fpu/softfloat-parts.c.inc index 6df98eb5fb..c5a828eb90 100644 --- a/fpu/softfloat-parts.c.inc +++ b/fpu/softfloat-parts.c.inc @@ -341,7 +341,17 @@ static void partsN(uncanon_normal)(FloatPartsN *p, float_status *s, g_assert_not_reached(); } - exp = p->exp + fmt->exp_bias; + /* Because exp_bias is positive, we can only overflow past INT_MAX. */ + if (sadd32_overflow(p->exp, fmt->exp_bias, &exp)) { + /* + * rebias_overflow wants to compute a modulo exponent, which + * conflicts with saturation. That said, saturation can only + * happen with scalbn, which is not a PowerPC operation. + */ + assert(!s->rebias_overflow); + exp = INT32_MAX; + } + if (likely(exp > 0)) { if (p->frac_lo & round_mask) { flags |= float_flag_inexact; -- 2.43.0
