Optimizing Immutable and Purity

[Bill Baxter]

On Tue, Dec 23, 2008 at 11:30 AM, Jerry Quinn <jlquinn at optonline.net> wrote:
> Walter Bright Wrote:
>
>> I've been working on improving the optimizer to take advantage of
>> immutability and purity.
>>
>> http://www.reddit.com/r/reddit.com/comments/7l5x4/optimizing_immutable_and_purity/
>>
>> http://dobbscodetalk.com/index.php?option=com_myblog&show=Optimizing-Immutable-and-Purity.html&Itemid=29
>
> This was an interesting read.  It would be nice to see a discussion of how const is going to fit in in terms of optimization potential, since you can always cast it away.

It's basically useless for optimizations I think.
Even if the view of the data you have is const, someone else might
have a non-const view of the same data.
So for instance, if you call any function, your "const" data could
have been changed via non-const global pointers to the same data.

--bb