[Cryptography] Speculation considered harmful?

Theodore Ts'o tytso at mit.edu
Tue Jan 9 17:46:07 EST 2018


On Tue, Jan 09, 2018 at 10:31:43AM -0800, Tom Mitchell wrote:
> ....
> The compilers at SGI were decent... and the engineers looked
> hard at the VLIW world and found it brutal.

Yet another problem with VLIW is that the optimizations tend to be
horribly architecture specific.  If you change the number of various
functional units, but you want to keep the instruction set backwards
compatibility, that's possible --- but if the compiler has to know how
the instructions will be scheduled, not only is it slow to compile,
but what is optimized for a particular version of Itanic might have be
terribe performance on a different version of the Itanic.

		       	 	   	      - Ted


More information about the cryptography mailing list