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Re: Problems with pragma and attribute optimize.
On Wed, Jul 25, 2012 at 4:25 PM, Allan Sandfeld Jensen
<carewolf@gmail.com> wrote:
> On Wednesday 25 July 2012, Richard Guenther wrote:
>> On Wed, Jul 25, 2012 at 2:23 PM, Allan Sandfeld Jensen
>>
>> <carewolf@gmail.com> wrote:
>> > Hi,
>> >
>> > I have been experimenting with marking specific functions to be auto-
>> > vectorized in GCC, but have had problems getting it to work.
>> >
>> > It seems the optimize attribute works sometimes, but only if the function
>> > it is used on is not static, but pragma optimize never seems to work.
>> >
>> > See the attached test-case. If you compile it with
>> > -ftree-vectorizer-verbose, you will see that only the first function is
>> > vectorized, but the two last are not.
>> >
>> > Anyone know what is wrong here?
>>
>> The attribute doesn't work in the face of inlining and generally was
>> designed for debugging, not for controlling things like you do.
>>
>
> In that case the GCC manual should probably be updated to reflect that. If
> what you say it true, it seems it has been developed for one purpose but then
> documented for another. (The documentation needs updating anyway, since the
> attribute is no longer allowed after the function declaration like all the
> examples does, but only before).
>
> I found the problem with pragma though, it is apparently a long standing bug
> in PR 48026 and a related version in PR 41201. The last bug actually has a
> patch for the problem, it is apparently caused by an incorrect short-cut.
CCing the original author.
Richard.
> `Allan