On 04/28/2014 06:05 AM, Dmitry Poletaev wrote:
> - env->cc_src = (eflags & ~(CC_C | CC_O)) |
> - (lshift(src ^ t0, 11 - (DATA_BITS - 1)) & CC_O) |
> + env->cc_src = (eflags & ~CC_C) |
> ((src >> (DATA_BITS - count)) & CC_C);
> + if (count == 1) {
> + env->cc_src |= (lshift(src ^ t0, 11 - (DATA_BITS - 1)) & CC_O);
> + }
This isn't what you described either, since you fail to clear the old value of
the O flag before oring in the new one. You wanted
if (count == 1) {
env->cc_src = (env->cc_src & ~CC_O)
| (lshift(src ^ t0, 11 - (DATA_BITS - 1)) & CC_O);
}
First off, do more testing before submitting patches.
Second, you've gotten an adequate description of why we're not going to take
patches to choose one particular undefined behaviour over another.
r~
