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From: "pinskia at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug middle-end/113180] MIPS: bitops on an long long struct uses ins
 instead dins (or with -mstrict-align on aarch64)
Date: Sun, 31 Dec 2023 06:37:28 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D113180

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Target|mips aarch64*-*-*           |mips aarch64*-*-* arm*-*

--- Comment #2 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
arm is just as bad:
```
xx:
        @ args =3D 8, pretend =3D 0, frame =3D 8
        @ frame_needed =3D 0, uses_anonymous_args =3D 0
        @ link register save eliminated.
        sub     sp, sp, #8
        mov     r3, r0
        strd    r1, r2, [sp]
        ldr     r1, [sp, #8]
        ldrb    r2, [sp, #7]    @ zero_extendqisi2
        bfi     r2, r1, #4, #4
        strb    r2, [sp, #7]
        ldrd    r0, r1, [sp]
        stm     r3, {r0, r1}
        mov     r0, r3
        add     sp, sp, #8
        @ sp needed
        bx      lr
```

Basically the variable a is stored to the stack and then modified and then
stored to the stack and then loaded and stored to the return location.

This is all due to STRICT alignment IIRC.=