locking problem with mips atomicity

[Michael Eager]

Richard Henderson wrote:
> 
> On Mon, Mar 15, 2004 at 03:57:02PM -0800, Michael Eager wrote:
> > -       "ll   %0,%3\n\t"
> > -       "addu %1,%4,%0\n\t"
> > -       "sc   %1,%2\n\t"
> > +       "la      %3,%2\n\t"
> > +       "ll   %0,0(%3)\n\t"
> > +       "addu %1,%5,%0\n\t"
> > +       "sc   %1,0(%3)\n\t"
> >         ".set pop\n\t"
> >         "beqz %1,1b\n\t"
> >         "/* End exchange & add */"
> > -       : "=&r"(__result), "=&r"(__tmp), "=m"(*__mem)
> > +       : "=&r"(__result), "=&r"(__tmp), "=m"(*__mem), "=r" (temp)
> 
> Better is to make the compiler force the address into a register.
> It may already be that way, resulting in "la r3,0(r4)".

This is exactly what this code does.   

--
Michael Eager     eager@mvista.com	408-328-8426	
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