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From: "rguenth at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug middle-end/113395] RTL expansion of bitfield accesses drops
 MEM_EXPR
Date: Mon, 15 Jan 2024 11:57:31 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D113395

Richard Biener <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
            Summary|RTL expansion drops         |RTL expansion of bitfield
                   |MEM_EXPR                    |accesses drops MEM_EXPR
             Blocks|                            |113255

--- Comment #2 from Richard Biener <rguenth at gcc dot gnu.org> ---
gcc.dg/tree-ssa/pr94969.c for example misses RTL PRE when we dumb down
find_base_term to be conservatively correct.  GIMPLE invariant motion
doesn't handle the involved aggregate copy which on RTL maps to SImode.


Referenced Bugs:

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D113255
[Bug 113255] [11/12/13/14 Regression] wrong code with -O2 -mtune=3Dk8=