Re: [PATCH] kvm/x86 : avoid shifting signed 32-bit value by 31 bits

From: H. Peter Anvin
Date: Mon Oct 15 2018 - 13:31:02 EST


On 10/15/18 10:23 AM, Paolo Bonzini wrote:
>
> Even for a value from a 32-bit register? That would be _BIT, which
> doesn't exist.
>

Just use _BITUL(). gcc is smart enough to know that that the resulting value
is representable in 32 bits.

Or if you really care, submit a patch to create _BITU(), but I don't
personally see much of a point.

-hpa