Sorry I missed the original post, but:
> + } else if (unlikely((XRb == 0) && (XRc == 0))) {
> + /* both operands zero registers -> just set destination to zero */
> + tcg_gen_movi_i32(mxu_gpr[XRa - 1], 0);
> + } else if (unlikely((XRb == 0) || (XRc == 0))) {
> + /* exactly one operand is zero register - find which one is not...*/
> + uint32_t XRx = XRb ? XRb : XRc;
> + /* ...and do max/min operation with one operand 0 */
> + if (opc == OPC_MXU_S32MAX) {
> + tcg_gen_smax_i32(mxu_gpr[XRa - 1], mxu_gpr[XRx - 1], 0);
> + } else {
> + tcg_gen_smin_i32(mxu_gpr[XRa - 1], mxu_gpr[XRx - 1], 0);
> + }
> + } else if (unlikely(XRb == XRc)) {
> + /* both operands same -> just set destination to one of them */
> + tcg_gen_mov_i32(mxu_gpr[XRa - 1], mxu_gpr[XRb - 1]);
You should not special case unlikely events, especially when ...
> + } else {
> + /* the most general case */
> + if (opc == OPC_MXU_S32MAX) {
> + tcg_gen_smax_i32(mxu_gpr[XRa - 1], mxu_gpr[XRb - 1],
> + mxu_gpr[XRc - 1]);
> + } else {
> + tcg_gen_smin_i32(mxu_gpr[XRa - 1], mxu_gpr[XRb - 1],
> + mxu_gpr[XRc - 1]);
> + }
... the normal case will handle those special cases just fine.
