Re: [RFC] [autovect patch] Implement vectorization hints

[Devang Patel <dpatel at apple dot com>]

On Feb 27, 2005, at 1:22 PM, Zdenek Dvorak wrote:

> In particular the node that you take in the
> vect_pragma_lookup function may have been moved there by some code
> motion optimization from elsewhere.

That should not change info about node's source location (unless it is 
generated by compiler).

> Or the loop itself could be created
> by some optimization (jump threading may do it sometimes).

In such cases user can not give any hints :)

> And these
> are just those that occured to me, I am fairly sure there are more.

I do not disagree. This is not straight forward, but unless plan is to 
attach pragma info with loop structures, I do not see any other very 
straight forward alternative. As soon as one says,
    User can put #pragma blah before the loop to give compiler hints...
"before" brings in lot of edge cases.


thoughts?

-
Devang