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From: "rguenth at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug tree-optimization/113372] wrong code with _BitInt() arithmetics at -O1
Date: Mon, 15 Jan 2024 13:04:18 +0000	[thread overview]
Message-ID: <bug-113372-4-1IOxZr2U3L@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-113372-4@http.gcc.gnu.org/bugzilla/>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113372

--- Comment #11 from Richard Biener <rguenth at gcc dot gnu.org> ---
So the key would be to make the object live again after a CLOBBER when such
address SSA name is used (but before any other explicit mention appears)?

The current algorithm relies on explitic mentions appearing, one original
idea was to turn those explicit mentions (or BLOCK starts) into
start-of-live CLOBBERs, but even that was shown to be not enough.

But yes, if we want to try to mitigate the problems somewhat without
doing a full solution then possibly even just looking at SSA defs
when POINTER_TYPE and the def is an ADDR_EXPR might work (in the
visit_* callbacks of the walk_stmt_load_store_addr_ops), no propagation
needed at all (basically just undo CSE virtually here for the simple
cases).

  parent reply	other threads:[~2024-01-15 13:04 UTC|newest]

Thread overview: 24+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2024-01-13  8:53 [Bug tree-optimization/113372] New: " zsojka at seznam dot cz
2024-01-13  9:03 ` [Bug tree-optimization/113372] " pinskia at gcc dot gnu.org
2024-01-15 10:28 ` jakub at gcc dot gnu.org
2024-01-15 10:33 ` jakub at gcc dot gnu.org
2024-01-15 11:25 ` jakub at gcc dot gnu.org
2024-01-15 11:31 ` rguenther at suse dot de
2024-01-15 11:51 ` jakub at gcc dot gnu.org
2024-01-15 12:07 ` jakub at gcc dot gnu.org
2024-01-15 12:19 ` rguenth at gcc dot gnu.org
2024-01-15 12:43 ` jakub at gcc dot gnu.org
2024-01-15 12:55 ` jakub at gcc dot gnu.org
2024-01-15 13:04 ` rguenth at gcc dot gnu.org [this message]
2024-01-15 13:35 ` jakub at gcc dot gnu.org
2024-01-15 13:47 ` rguenther at suse dot de
2024-01-15 14:35 ` jakub at gcc dot gnu.org
2024-01-15 14:42 ` rguenth at gcc dot gnu.org
2024-01-15 14:43 ` matz at gcc dot gnu.org
2024-01-15 14:58 ` jakub at gcc dot gnu.org
2024-01-16  7:21 ` rguenther at suse dot de
2024-01-16 10:51 ` cvs-commit at gcc dot gnu.org
2024-01-16 10:56 ` jakub at gcc dot gnu.org
2024-01-20 17:09 ` pinskia at gcc dot gnu.org
2024-03-02  0:38 ` cvs-commit at gcc dot gnu.org
2024-03-28 11:01 ` jakub at gcc dot gnu.org

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