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Re: [ID 20000409.003] Disappearing constant values

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Gurusamy Sarathy
April 10, 2000 11:15
Re: [ID 20000409.003] Disappearing constant values
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On Mon, 10 Apr 2000 17:53:38 BST, Nick Ing-Simmons wrote:
>Gurusamy Sarathy <> writes:
>>>Is setting PADTMP on a constant the right thing to do in the first place?
>>Yes.  The constant SV is moved to the pad in order to keep it separate
>>between different threads that might share the same op tree.  
>Presumably then this is one of the 'named' kind - as we don't want
>constants being used as scratch. 

"Used as scratch" depends on the particular op.  While that is
usually the case, it is not always so.  (It is probably more
approprate to think of it as a "holding cell" rather than as
a "scratch value".)

>So perhaps there are three types:
>  1. named variables
>  2. constants 
>  3. Pad temporaries. 

There's also:

   4. GVs

Note that #2 and #4 are only applicable to ithreads.


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