.global atanf
.type atanf,@function
atanf:
        flds 4(%esp)
        mov 4(%esp),%eax
        add %eax,%eax
        cmp $0x01000000,%eax
        jb 1f
        fld1
        fpatan
        ret
                # subnormal x, return x with underflow
1:      fld %st(0)
        fmul %st(1)
        fstps 4(%esp)
        ret