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Re: Fix PR tree-optimization/28778, 29156, and 29415

On 10/20/06, Jan Hubicka <> wrote:
> This large patch fixes three P1 regressions, 28778, 29156, 29415.
> The basic issue in all three is that previously, we had no way to
> describe accesses to nonlocal memory.   When we had no addressable
> variables, we generated no conflicting vuses, even if we were
> dereferencing pointers or passing them to other functions.
> As our aliasing has gotten better, it eventually got to the point
> during 4.2 that we could eliminate all local aliases, and be left with
> nothing to say things aliased.  It was still possible to construct
> these cases with 4.x, it's just *much much* harder.
> Sadly, there is no smaller, less risky, and correct fix i can think of
> for this problem that will not cause either massive compile time
> explosion, or massive performance loss (I tried some before making
> this statement).

sadly this patch cause up to 9% memory consumption increase on my
testsuite (and the increase is almost consistent across all testcases).
New memory logs are
if you need the logs just before the run, I can get them easilly.

I'm aware. The other patches would have been about 50% memory consumption increase, and about 30-50% compile time slowdown (yeah, those are real numbers, the number of vops just goes ballistic).

Try the attached and let me know if it helps please!

Attachment: speedup.diff
Description: Binary data

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