Quote:
Originally Posted by Gorf
sophisticated branch prediction takes a lot of space - hints in the code could render this irrelevant
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I heard IBM Power did that in the past, and the hint bit is now ignored because ordinary branch prediction works better.
Hints in the code also take space, btw. Encoding space is valuable and there are better uses for it.
Quote:
Originally Posted by Gorf
think of nested loops and the effort it takes to analyze them - again hints could be very useful here
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What kind of analyze ?
Quote:
Originally Posted by Gorf
no - that is why we need that information from the coder.
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What information ? This is wholly unclear.
Quote:
Originally Posted by Gorf
it should provide the opposite: enough hints and clarity to allow AOT binary2binary translation into any target.
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If implementation is visible in the instruction set, then this makes next implementation problematic if it does it differently.
If one day we get a nice asic, these emulation hints will look ridiculously useless.
I've said that somewhere before, but don't forget that
architectures persist longer than implementations.
Quote:
Originally Posted by Gorf
(And no: I have not the slightest clue how to do this - apparently nobody does.)
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Hints given to some machine to build some program are called
code. Thus "enough hints" is like performing the conversion yourself.