On 2023/4/7 03:33, Richard Henderson wrote:
On 4/6/23 00:25, Weiwei Li wrote:
+static target_ulong legalize_mpp(CPURISCVState *env, target_ulong
old_mpp,
+ target_ulong val)
+{
+ target_ulong new_mpp = get_field(val, MSTATUS_MPP);
+ bool mpp_invalid = (new_mpp == PRV_S && !riscv_has_ext(env,
RVS)) ||
+ (new_mpp == PRV_U && !riscv_has_ext(env,
RVU)) ||
+ (new_mpp == PRV_H);
+
+ /* Remain field unchanged if new_mpp value is invalid */
+ return mpp_invalid ? set_field(val, MSTATUS_MPP, old_mpp) : val;
+}
Does anyone find PRV_H confusing, since that's not what it is?
I think it would be nice to remove it entirely.
I agree. Maybe PRV_RESERVED is more readable in some cases.
This function might be better as
bool valid = false;
switch (new_mpp) {
case PRV_M:
valid = true;
break;
case PRV_S:
valid = riscv_has_ext(env, RVS);
break;
case PRV_U:
valid = riscv_has_ext(env, RVU);
break;
}
if (!valid) {
val = set_field(...);
}
return val;
OK. This is more readable. I'll update this.
Regards,
Weiwei Li
r~
