Re: <architecture> and <instruction-set>

From: David Abrahams (dave_at_[hidden])
Date: 2005-10-20 10:51:09

Reece Dunn <msclrhd_at_[hidden]> writes:

> Vladimir Prus <ghost <at> cs.msu.su> writes:
>
>> 
>> On Wednesday 19 October 2005 19:33, Alexey Pakhunov wrote:
>> > Reece Dunn wrote:
>> > > + # sh
>> > > + sh3 sh3dsp sh4 sh5
>> >
>> > Can these shXxx be expressed via combinations of <architecture>sh and
>> > different <address-model> and <instruction-set>?
>> 
>> Good question. Anybody has a semi-formal definition of <architecture> and 
>> <instruction-set> features?
>
> How about:
>
> <architecture> specifies the general CPU type being used. That is, what
> architectural design is being used on the chip. For example, x86 specifies the
> Intel X86 based CPUs such as Pentium 4.
>
> <instruction-set> specifies what CPU/assembler instructions are available for
> the given architecture. For example, using the instructions available with the
> AMD Athalon CPU.

So far, I see no advantage in distinguishing these. What's the point
of <architecture>, anyway? Isn't that completely determined by the
instruction-set chosen?

<facetious>
If you specify <architecture>x86 and no <instruction-set> does it
assume you're on an 8086?
</facetious>

-- 
Dave Abrahams
Boost Consulting
www.boost-consulting.com