On 7/11/24 1:24 AM, Kewen.Lin wrote:
> Sorry for the confusion, I meant for most target options when we emit some
> error
> message meanwhile we also unset it, such as:
>
> if (TARGET_CRYPTO && !TARGET_ALTIVEC)
> {
> if (rs6000_isa_flags_explicit & OPTION_MASK_CRYPTO)
> error ("%qs requires %qs", "-mcrypto", "-maltivec");
> rs6000_isa_flags &= ~OPTION_MASK_CRYPTO;
> }
That is not what is happening here though. The code here to disable
crypto is for the case where crypto is enabled implicitly, via say
-mcpu=power8, but the user has also explicitly disabled Altivec which
crypto depends on. In that case, we do not emit an error or warning and
we silently disable crypto. This is similar to -mcpu=power8 -mno-altivec
where we silently disable VSX. The other cases you showed are of similar
scenarios.
In my ROP code, we know ROP was explicitly enabled (it is never turned on
implicitly with any -mcpu= option) and the target cpu and/or ABI does
not support it, so there's nothing more to do, other than to emit an error.
There is no matching implicit use case where we silently disable ROP as
there was in your case above. Therefore, I think the code as I showed it
is correct as is...other than the code snipit location, which I have moved
and am testing now.
Peter
