.global atan .type atan,@function atan: fldl 4(%esp) mov 8(%esp),%eax add %eax,%eax cmp $0x00200000,%eax jb 1f fld1 fpatan ret # subnormal x, return x with underflow 1: fnstsw %ax and $16,%ax jnz 2f fsts 4(%esp) 2: ret