Rich kids are into COBOL
Guy Sotomayor
ggs at shiresoft.com
Fri Feb 27 12:30:06 CST 2015
> On Feb 27, 2015, at 10:27 AM, Chuck Guzis <cclist at sydex.com> wrote:
>
> On 02/27/2015 06:29 AM, Peter Corlett wrote:
>
>
>> C does support bitfields, but can't take the address of one. The latter is a
>> fairly uncommon requirement though, and so algorithms that require it will have
>> to roll their own using mask and shift operations. Given that x86 doesn't have
>> bitfield instructions and has to fake it with mask and shift, this is no great
>> loss in practice. It wouldn't surprise me if there was a bitfield_ptr<> in
>> Boost which did this.
>
> Well, the 386+ CPUs have bit manipulation instructions and *almost* had bit string/field instructions. There are still books out there that describe in detail the function of the BFxxx instructions.
>
> I suppose that it's unreasonable for a language to support processor instruction set extensions. But APL does a great job of supporting vectors; has a syntax for things such as dot-product, etc. So it can't be that K&R weren't aware of such things.
>
> It seems to me to be very strange that today we're coding in a language that was developed for a PDP-11 minicomputer.
The frustrating thing for me is not just the instructions but the memory model. Some of the issues (security springs to mind) that
we're facing today can be solved by *not* having a completely flat memory model. I'm still a fan of tagged memory. ;-)
TTFN - Guy
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