--- Comment #8 from Wilco <wilco at gcc dot> ---
(In reply to Jakub Jelinek from comment #7)
> cfun->has_nonlocal_label instead of cfun->calls_setjmp would cover
> __builtin_setjmp.
> aarch64_frame_pointer_required would force frame_pointer_needed and thus be
> true in that case too.  But sure, if it works, we can change:
>    /* Force a frame chain for EH returns so the return address is at FP+8. 
> */
>    cfun->machine->frame.emit_frame_chain
> -    = frame_pointer_needed || crtl->calls_eh_return;
> +    = frame_pointer_needed || crtl->calls_eh_return ||
> cfun->has_nonlocal_label;

Note I'm not convinced this is sufficient. I tried compiling
testsuite/gcc.c-torture/execute/pr60003.c and it appears to mess up the frame
pointer so it no longer points to a frame chain:

        adrp    x1, .LANCHOR0
        add     x0, x1, :lo12:.LANCHOR0
        stp     x29, x30, [sp, -16]!
        mov     x29, sp
        ldr     x2, [x0, 8]
        ldr     x29, [x1, #:lo12:.LANCHOR0]  // load of bad frame pointer
        ldr     x0, [x0, 16]
        mov     sp, x0
        br      x2

        stp     x29, x30, [sp, -176]!
        adrp    x2, .LANCHOR0
        add     x1, x2, :lo12:.LANCHOR0
        mov     x29, sp
        add     x3, sp, 176                  // store of bad frame pointer
        str     x3, [x2, #:lo12:.LANCHOR0]
        stp     x19, x20, [sp, 16]
        stp     x21, x22, [sp, 32]
        stp     x23, x24, [sp, 48]
        stp     x25, x26, [sp, 64]
        stp     x27, x28, [sp, 80]
        stp     d8, d9, [sp, 96]
        stp     d10, d11, [sp, 112]
        stp     d12, d13, [sp, 128]
        stp     d14, d15, [sp, 144]
        str     w0, [sp, 172]
        adrp    x0, .L7
        add     x0, x0, :lo12:.L7
        str     x0, [x1, 8]
        mov     x0, sp
        str     x0, [x1, 16]
        bl      baz
        .p2align 2
        ldr     w0, [sp, 172]
        ldp     x19, x20, [sp, 16]
        ldp     x21, x22, [sp, 32]
        ldp     x23, x24, [sp, 48]
        ldp     x25, x26, [sp, 64]
        ldp     x27, x28, [sp, 80]
        ldp     d8, d9, [sp, 96]
        ldp     d10, d11, [sp, 112]
        ldp     d12, d13, [sp, 128]
        ldp     d14, d15, [sp, 144]
        ldp     x29, x30, [sp], 176

What should happen is that it stores the actual sp/fp just before calling baz,
and baz then restores those before jumping to L7.

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