Impact of Dual Placement and Routing on WDDL Netlist Security in FPGA

Algorithm 2

Determining the index of the equivalent node 𝑛^′.

Let:  n the node currently being routed

  pred(n) the predecessor node of node 𝑛.

  count(n) an incremental value reserved to node 𝑛

index(src) = 0;

count(src) = 0;

index(𝑛) = index (pred(𝑛)) + 1;

count(𝑛) = count (pred(𝑛));

if (Diff_sw_nb  (i,  n,  j)) <=0) { /*the current routing path is the shorter or

            equal to the dual routing path*/

 if (𝑛 ! = 𝑗) { /*case a*/

  index(𝑛^′) = index(𝑛);

  count(𝑛) ++

 }

 else { /*case b*/

  index(𝑛^′) = index(𝑗^′);

 }

}

else { /*the current routing path is longer than the dual routing path*/

 equivalent_index  =  Total_sw_nb(𝑖^′, 𝑗^′) − Expected_sw_nb(𝑛, 𝑗);

 if (equivalent_index < count(𝑛) + 1) { /*case c*/

  index(𝑛^′) = count(𝑛);

 }

 else { /*case d*/

  index(𝑛^′) = equivalent_index;

  count(𝑛) ++;

 }

}