pushl   %ebp
movl    %esp,%ebp

#i've to do ((X/2)*K1)

movl    %ebx,-12(%ebp)      #X to stack
movl    $2,-8(%ebp)     #2 to stack
movl    K1,%eax
movl    %eax,-4(%ebp)       #K1 to stack

fildl   -12(%ebp)
fildl   -8(%ebp)
fildl   -4(%ebp)
fdivp   %st(0),%st(1)       #X/2
fmulp   %st(0),%st(1)       #(X/2)*K1

fist    -4(%ebp)
movl    -4(%ebp),%eax       #result to eax casted as int
popl    %ebp

ret