fix code path where child function returns in arm __clone built as thumb

[musl] / src / ldso / x86_64 / tlsdesc.s

.text
.global __tlsdesc_static
.hidden __tlsdesc_static
.type __tlsdesc_static,@function
__tlsdesc_static:
        mov 8(%rax),%rax
        ret

.hidden __tls_get_new

.global __tlsdesc_dynamic
.hidden __tlsdesc_dynamic
.type __tlsdesc_dynamic,@function
__tlsdesc_dynamic:
        mov 8(%rax),%rax
        push %rdx
        mov %fs:8,%rdx
        push %rcx
        mov (%rax),%rcx
        mov 8(%rax),%rax
        add (%rdx,%rcx,8),%rax
        pop %rcx
        sub %fs:0,%rax
        pop %rdx
        ret