[Bug regression/35671] GCC 4.4.x vs. 4.2.x performance regression

[manu at gcc dot gnu dot org]

------- Comment #16 from manu at gcc dot gnu dot org  2009-07-30 12:02 -------
(In reply to comment #8)
> If anyone cares to repeat my test results, here's a simple test case:

This is not a simple testcase. A simple testcase is a sufficiently small
self-contained compilable code that shows the problem in a way that can be
reliably and consistently reproduced. The ideal testcase would be the smallest
possible still showing the problem but anything below 100 lines of preprocessed
code is probably small enough.

There are currently 3615 bugs opened. Many of them have simple testcases and
some of them even provide what is the difference in the generated code that
leads to worse performance. This problem report provides neither. Guess which
one is more likely to be worked on.

Each of the following steps increases the chances of getting a problem fixed:

1. Provide a self-contained testcase.
2. Provide a very small self-contained testcase.
3. Describe the differences in the generated code that leads to worse
performance.
4. Find the exact flags that trigger the loss in performance.
5. Find the exact revision that introduced the loss in performance.
6. Find the exact code in GCC that contains the bug.

(In reply to comment #9)
> I hope GCC 4.5.0 will become sane again.

You mean that you hope that your current problems get fixed by chance. If you
cannot wait for the surprise, just grab a recent snapshot or current SVN trunk
and check it out. Good luck!


-- 

manu at gcc dot gnu dot org changed:

           What    |Removed                     |Added
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                 CC|                            |manu at gcc dot gnu dot org


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=35671