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Is this NG still monitored, as there seem to have been no posts here since last July?

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gareth

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Dec 4, 2015, 1:53:37 PM12/4/15
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As per subject


druck

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Dec 4, 2015, 4:37:46 PM12/4/15
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On 04/12/2015 18:53, gareth wrote:
> As per subject

It got this far.

---druck

gareth

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Dec 4, 2015, 6:02:40 PM12/4/15
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"druck" <ne...@druck.org.uk> wrote in message
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> On 04/12/2015 18:53, gareth wrote:
>> As per subject
>
> It got this far.

OK, This is my interest.

With the32-bit instruction set having conditional execuation based upon
previously-set condition codes, what happens if there is a nested IF, if
the conditions for execution are based upon the result of the outer IF?

Presumably the outer IF has to be resolved by conditional branches and not
by
conditional execution?


druck

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Dec 6, 2015, 4:15:37 PM12/6/15
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On 04/12/2015 23:02, gareth wrote:
> OK, This is my interest.
>
> With the32-bit instruction set having conditional execuation based
> upon previously-set condition codes, what happens if there is a
> nested IF, if the conditions for execution are based upon the result
> of the outer IF?
>
> Presumably the outer IF has to be resolved by conditional branches
> and not by conditional execution?

Yes.

It my be possible to come up with inner and outer conditions based on
mutually exclusive flag combinations, but in modern ARMs with branch
prediction, a branch is going to be quicker than skipping large chunks
of not taken conditional instructions.

---druck

gareth

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Dec 6, 2015, 5:09:33 PM12/6/15
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"druck" <ne...@druck.org.uk> wrote in message
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Thanks.


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