how do I write a function with cell input from matlab to c code?

Hi everyone: my matlab code as follow:

                  function [ XP ] = seqRe_ali( test_cut, model_cut,P ) 
                   for i = 1 : size(P,1)
                    c = P(i,3);
                    t = P(i,2);
                    m = P(i,1);
                    reTest_ali{i} = test_cut{t}(c,:);
                    reModel_ali{i} = model_cut{m};
                   end
                 for i = 1 : size(reTest_ali,2)
                     reTest_matrix(i,:) = reTest_ali{i};
                 end   
                 for i = 1 : size(reModel_ali,2)
                     reModel_matrix(i,:) = reModel_ali{i};
                 end  
                  % Xs is like Xi*Wi' and Yi*Wi'.
                 XP{1} = reTest_matrix';
                 XP{2} = reModel_matrix';
              end

where the input test_cut, model_cut is two cell with size 1*n, 1*m and in each cell is a matrix with size r*c; p is the matrix with size t*3; How do I switch these matlab code c code, because I want use cmex to call the c code in matlab to accelerate the run speed. Thank you so much.