peak value and its index without using max function ...max function not supported in HDL coder

In Matlab there is command which finds the peak value and its index of vector xc like this [x y]=max(xc) where x is the peak value and y is its index.Now the problem is this max function is not supported in HDL coder and I have to convert matlab code to VHDL using HDL Coder .Does any one any any other way to find peak and its index like max command does. with small example.I will really appreciate your reply please.