[r-t] PB6 search completes

[Mark Davies]

Graham writes,

> There should be some optimisation possible using the 64 bit registers and
> instructions too - causing a rename to SMC64!

I haven't looked through all the SSE instructions, so there might be 
something useful. However, SMC32 already makes use of the 64-bit MMX 
registers (useful for counts) and I think you're not worse off using 
those compared to the newer 64-bit instructions unless you're trying to 
do floating point at the same time (MMX and FPU registers being shared).

MBD