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From: "rguenth at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug target/109476] Missing optimization for 8bit/8bit
 multiplication / regression
Date: Wed, 12 Apr 2023 11:14:28 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D109476

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |rguenth at gcc dot gnu.org

--- Comment #2 from Richard Biener <rguenth at gcc dot gnu.org> ---
I get

_Z3mulhj:
/* prologue: function */
/* frame size =3D 0 */
/* stack size =3D 0 */
.L__stack_usage =3D 0
        mov r22,r24
        mov r24,r23
        ldi r23,0
        ldi r25,0
        rcall __mulhi3

but probably because you didn't specify the actual command to compile and
I'm using the wrong subarchitecture.

What probably regressed is that we're promoting the multiplication to
'int'.  The same happens for the + 1 variant for me though.

Can you share the -march required to have 16bit multiplication?=