All of them, through software implementation, as assembly programmers have done since forever.
You simply choose the integer type that your problem or task requires. If the hardware genuinely can‘t cope with it (performance), you reevaluate your requirements, define new constraints and choose new types. This is basic requirements engineering, which C only made more convoluted.
I think overall it's better to provide "natural" default types but also have had something like stdint.h. But then again mandatong even a stdint.h that early would have made writing implementations quite difficult. I think it was and is an alright tradeoff.
You simply choose the integer type that your problem or task requires. If the hardware genuinely can‘t cope with it (performance), you reevaluate your requirements, define new constraints and choose new types. This is basic requirements engineering, which C only made more convoluted.