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Subject: Re: Performance of records with variant parts
Date: Mon, 22 Mar 2021 20:31:43 +0100
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On 3/22/21 6:49 PM, John Perry wrote:
> 
> This is a raytracing program. There are no particular timing requirements, but if I wanted a larger image with more objects things would get ugly. This is really more a matter of my curiosity.

If you have no timing requirements, then you don't care how long it takes and 
have no issue.

> 
> Obj is an "in" parameter to a function. Do you need more than that?

Yes.

What compiler and optimization option are you using? I would expect any compiler 
(except GNAT at -O0) to optimize away any discriminant checks on direct accesses 
to variant components in the branches of the case statement.

Is Obj passed to any subprograms from the branches of the case statement? Are 
any variant components accessed outside of the case statement?

-- 
Jeff Carter
"One day he told me he was a gynecologist. He
couldn't speak no foreign languages."
Take the Money and Run
147