I'm trying to write  some experimental mutex operations similar to those
in -current, but to do differnt things (e.g. a read/write lock)
however, I am having some problems with the __asm  stuff.

What I want to do is to define some operations that will
assemble down to:

I can generate the code, but it seems to me that there should be 
a way of telling gcc that you have just pushed an item onto the stack, 
so that if you were to have some C code between the push and po 
(of the flags reg) the compiler has a correct idea of where the 
SP is. I can imagine that it doesn't matter so it may be that there 
is no constaint for that purpose (I read the gcc asm info pages)
but I wanted to make sure that that is the case because if it does turn
out to be important, it may manifest itself as a wierd bug sometime 
in 2002.

The current pushfl code in the kernel has the following:
        __asm __volatile("pushfl; popl %0" : "=r" (ef));
which has no long term effect on the stack pointer so I cannot 
use it as a guide.

      __--_|\  Julian Elischer
     /       \ [EMAIL PROTECTED]
    (   OZ    ) World tour 2000
---> X_.---._/  presently in:  Budapest

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