plans for 64bit support (Joshua Root)

[Vincent Lefevre]

On 2007-12-20 17:59:25 +1100, Joshua Root wrote:
> [1] <http://lixom.net/~olof/64bit-perf.pdf>
> [2] <http://www.geekpatrol.ca/2006/09/32-bit-vs-64-bit-performance/>

I don't understand why they say that 5 instructions are needed for
constants in 64-bit binaries. Can't the PowerPC load the constant
from the memory with a single instruction? This is the solution
chosen on the ARM for complex constants (if they are in the cache,
this should be fast enough). But many constants are simple enough
to be loaded with a single instruction (on the ARM, these are 8-bit
values rotated by an even number of positions), in particular after
optimizing the code.

-- 
Vincent Lefèvre <vincent at vinc17.org> - Web: <http://www.vinc17.org/>
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