[Bug target/82150] Produces a branch prefetch which causes a hang

[david.welch at netronome dot com via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=82150

--- Comment #13 from david.welch at netronome dot com ---
Very sorry it has been years since I did this research, a simple nop wont fix
it but a branch to self will.

bad

TEST:
        push {r4,lr}
        pop {r4,pc}
        bx r0 /*.hword 0x4700*/
        nop
        nop

bad

TEST:
        push {r4,lr}
        pop {r4,pc}
        nop
        bx r0 /*.hword 0x4700*/
        nop
        nop


good

TEST:
        push {r4,lr}
        pop {r4,pc}
        b .
        bx r0 /*.hword 0x4700*/
        nop
        nop