Fwd: Possible regression in DF analysis

[Claudiu Zissulescu Ianculescu <claziss@gmail.com>]

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---------- Forwarded message ---------
From: Claudiu Zissulescu Ianculescu <claziss@gmail.com>
Date: Tue, Dec 20, 2022 at 2:31 PM
Subject: Re: Possible regression in DF analysis
To: Jeff Law <jeffreyalaw@gmail.com>


Hi Jeff,

> Or is that the core of the problem -- that life analysis is inaccurate
> or unavailable?
>
The life analysis is not accurate/missing and loop-doloop check is not
performed, leading in inserting the doloop end pattern when it
shouldn't.
The issue is how df_analyse_loop sets the df problem subset, not
including the destination BB from the exit edges of a loop. I am
looking now how loop_post_order_compute and
loop_inverted_post_order_compute can include those missing BBs too.

Thanks,
Claudiu