Re: BUILD_SMP_TIMER_INTERRUPT not needed movl

Gabriel Paubert (paubert@iram.es)
Tue, 11 Aug 1998 20:27:31 +0200 (METDST)


On Tue, 11 Aug 1998, Richard B. Johnson wrote:

> The first reference I find to a difference (for stack operation) was with
> the i486 p.p. 22-5, Intel486 Programmer's Reference Manual.
>

>From the latest and greatest (well quite recent anyway) Intel architecture
doc (24319201.pdf, you've just got to love Intel's poetic names), section
17.10.1 which is dedicated to the behaviour of the `push sp' instruction:

`The P6 family, Pentium, Intel486, Intel386, and Intel 286 processors push
a different value on the stack for a PUSH SP instruction than the 8086
processor. The 32-bit processors push the value of the SP register before
it is decremented as part of the push operation; the 8086 processor pushes
the value of the SP register after it is decremented.'

They qualify the 286 as a 32-bit processor (!) but I quite clearly
remember that `push sp' behaviour was a test to check whether you had a
8088/8086 or 286 when the AT came out.

Gabriel.

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.rutgers.edu
Please read the FAQ at http://www.altern.org/andrebalsa/doc/lkml-faq.html