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Date: Fri, 10 Sep 2021 13:16:40 +0000 (UTC)
From: Michael Matz <matz@suse.de>
To: Aldy Hernandez <aldyh@redhat.com>
cc: gcc-patches <gcc-patches@gcc.gnu.org>
Subject: Re: More aggressive threading causing loop-interchange-9.c regression
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Hi,

On Fri, 10 Sep 2021, Aldy Hernandez via Gcc-patches wrote:

>      }
> +
> +  /* Threading through a non-empty latch would cause code to be added

"through an *empty* latch".  The test in code is correct, though.

And for the before/after loops flag you added: we have a 
cfun->curr_properties field which can be used.  We even already have a 
PROP_loops flag but that is set throughout compilation from CFG 
construction until the RTL loop optimizers, so can't be re-used for what 
is needed here.  But you still could invent another PROP_ value instead of 
adding a new field in struct function.


Ciao,
Michael.