Re: the 'switch' limit...

On Sun, Nov 01, 2009 at 12:59:06PM -0700, BGB / cr88192 wrote:

but, the hash is not used for opcode lookup/decoding, rather it is used for
grabbing already decoded instructions from a cache (which is based on memory
address).

You could extend this to work on blocks of instructions rather than on single
instructions, where blocks start at places that are jumped to by the program.

If you do that, you will have to do the decoding of x86 code and the hash
table lookups far less often. I believe this is what QEMU does (they call
it "dynamic translation").

Regards,

Bob

--
Whenever people say "I thought", they were usually wrong.



.

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