--- Comment #9 from Richard Earnshaw <rearnsha at gcc dot> ---
(In reply to Wilco from comment #8)
> (In reply to Segher Boessenkool from comment #5)
> > The first one just needs an xfail.  I don't know if it should be *-*-* there
> > or only arm*-*-* should be added.
> > 
> > The other two need some debugging by someone who knows the target and/or
> > these tests.
> The previous code for Arm was:
>       cbz     r0, .L5
>       push    {r4, lr}
>       mov     r4, r0
>       bl      foo
>       movw    r2, #:lower16:.LANCHOR0
>       movt    r2, #:upper16:.LANCHOR0
>       add     r4, r4, r0
>       str     r4, [r2]
>       pop     {r4, pc}
> .L5:
>       movs    r0, #1
>       bx      lr
> Now it fails to shrinkwrap:
>       push    {r4, lr}
>       mov     r4, r0
>       cmp     r4, #0
>       moveq   r0, #1
>       beq     .L3
>       bl      foo
>       ldr     r2, .L7
>       add     r3, r4, r0
>       str     r3, [r2]
> .L3:
>       pop     {r4, lr}
>       bx      lr
> It seems shrinkwrapping is more random, sometimes it's done as expected,
> sometimes it is not. It was more consistent on older GCC's.

This looks like another fallout of not allowing combine to merge with hard
regs.  Previously the CBZ could be moved outside of the prologue because it
operated directly on the incoming hard reg.  Now it only sees the value after
the copy into the pseudo, which is a call-saved reg because it's live over the

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