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@@ -1,5 +1,6 @@
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-module floating_add #(parameter N=16, M=4)(input_1, input_2, sum, diff);
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+module floating_add #(parameter N=16, M=4)(input_1, input_2, sum, diff, clk, reset);
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input logic [N-1:0] input_1, input_2;
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+ input logic clk, reset;
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output logic [N-1:0] sum;
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output logic [M:0] diff;
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@@ -8,117 +9,145 @@ module floating_add #(parameter N=16, M=4)(input_1, input_2, sum, diff);
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logic [M:0] abs;
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logic [N-3-M:0] res;
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+ logic [N-1:0] D0 [7:0];
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+ logic [N-1:0] Q0 [7:0];
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+ logic [N-1:0] Q1 [7:0];
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+ logic [N-1:0] Q2 [7:0];
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+
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// sign_x = x[N-1]
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// exponent_x = x[N-2:N-2-M]
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// mantissa_x = x[N-3-M:0]
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+ //First pipeline stage
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+ always_comb
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+ begin
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+ D0[0] = input_1;
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+ D0[1] = input_2;
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+ D0[2] = 0; // sum
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+ D0[3] = 0; // diff
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+ D0[4] = 0; // flag_a
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+ D0[5] = 0; // flag_b
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+ D0[6] = 0; // abs
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+ D0[7] = 0; // res
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+ end
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+ pipe pipe0(.clk(clk), .reset(reset), .D(D0), .Q(Q0));
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+
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+
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always_comb
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begin
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- if (input_1[N-2:N-2-M] > input_2[N-2:N-2-M]) // If input 1 has the bigger exponent
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+ if (Q0[0][N-2:N-2-M] > Q0[1][N-2:N-2-M]) // If input 1 has the bigger exponent
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begin
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// Flags input a as larger and calculates the absolute difference
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- flag_a = 1;
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- flag_b = 0;
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- abs = input_1[N-2:N-2-M] - input_2[N-2:N-2-M];
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+ Q0[4] = 1;
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+ Q0[5] = 0;
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+ Q0[6] = Q0[0][N-2:N-2-M] - Q0[1][N-2:N-2-M];
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// ASsigning overall sign of the output
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- sum[N-1] = input_1[N-1];
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+ Q0[2][N-1] = Q0[0][N-1];
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// Sets output to have the same exponent
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- sum[N-2:N-2-M] = input_1[N-2:N-2-M];
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+ Q0[2][N-2:N-2-M] = Q0[0][N-2:N-2-M];
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end
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- else if (input_2[N-2:N-2-M] > input_1[N-2:N-2-M]) // If input 2 has the bigger exponent
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+ else if (Q0[1][N-2:N-2-M] > Q0[0][N-2:N-2-M]) // If input 2 has the bigger exponent
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begin
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// Similarly flags input b as larger and calculates the absolute difference
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- flag_a = 0;
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- flag_b = 1;
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- abs = input_2[N-2:N-2-M] - input_1[N-2:N-2-M];
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+ Q0[4] = 0;
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+ Q0[5] = 1;
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+ Q0[6] = Q0[1][N-2:N-2-M] - Q0[0][N-2:N-2-M];
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// ASsigning overall sign of the output
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- sum[N-1] = input_2[N-1];
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+ Q0[2][N-1] = Q0[1][N-1];
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// Sets ouput to have the same exponent
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- sum[N-2:N-2-M] = input_2[N-2:N-2-M];
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+ Q0[2][N-2:N-2-M] = Q0[1][N-2:N-2-M];
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end
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else
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begin
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// THe condition that both inputs have the same exponent
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- flag_a = 1;
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- flag_b = 1;
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- abs = 0;
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+ Q0[4] = 1;
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+ Q0[5] = 1;
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+ Q0[6] = 0;
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// ASsigning overall sign of the output based on size of the mantissa
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- if (input_1[N-3-M:0] >= input_2[N-3-M:0]) sum[N-1] = input_1[N-1];
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- else sum[N-1] = input_2[N-1];
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- sum[N-2:N-2-M] = input_1[N-2:N-2-M];
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+ if (Q0[0][N-3-M:0] >= Q0[1][N-3-M:0]) Q0[2][N-1] = Q0[0][N-1];
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+ else Q0[2][N-1] = Q0[1][N-1];
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+ Q0[2][N-2:N-2-M] = Q0[0][N-2:N-2-M];
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end
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- diff = abs;
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+ Q0[3] = Q0[6];
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end
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+ //Second pipeline stage 1
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+ pipe pipe0(.clk(clk), .reset(reset), .D(Q0), .Q(Q1));
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+
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always_comb
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begin
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// Condition for overflow is that it sets the output to the larger input
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- if (abs > 9) // Because size of mantissa is 10 bits and shifting by 10 would give 0
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+ if (Q1[6] > N-2-M) // Because size of mantissa is 10 bits and shifting by 10 would give 0
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begin
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- if (flag_a & ~flag_b) sum = input_1; // input 1 is larger and is translated to output
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- else if (~flag_a & flag_b) sum = input_2; // input 2 is larger and is translated to output
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+ if (Q1[4] & ~Q1[5]) Q1[2] = Q1[0]; // input 1 is larger and is translated to output
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+ else if (~Q1[4] & Q1[5]) Q1[2] = Q1[1]; // input 2 is larger and is translated to output
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else // exponents are the same
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begin
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- if (input_1[N-3-M:0] >= input_2[N-3-M:0]) sum = input_1;// input 1 has the bigger mantissa
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- else sum = input_2; // input 2 has the bigger mantissa
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+ if (Q1[6][N-3-M:0] >= Q1[1][N-3-M:0]) Q1[2] = Q1[0];// input 1 has the bigger mantissa
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+ else Q1[2] = Q1[1]; // input 2 has the bigger mantissa
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end
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end
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else
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begin
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// Shifts the smaller input's mantissa to the right based on abs
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- if (flag_a & ~flag_b)// If input 1 has the larger exponent
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+ if (Q1[4] & ~Q1[5])// If input 1 has the larger exponent
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begin
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// If the signs of both inputs are the same you add, otherwise you subtract
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- if (input_1[N-1] == input_2[N-1])
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+ if (Q1[0][N-1] == Q1[1][N-1])
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begin
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- res = input_1[N-3-M:0] + (input_2[N-3-M:0] >> abs-1); // Sum the mantissa
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- sum[N-3-M:0] = res;
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+ Q1[7] = Q1[0][N-3-M:0] + (Q1[1][N-3-M:0] >> Q1[6]-1); // Sum the mantissa
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+ Q1[2][N-3-M:0] = Q1[7];
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end
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else
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begin
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- res = input_1[N-3-M:0] - (input_2[N-3-M:0] >> abs-1); // Subtract the mantissas
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+ Q1[7] = Q1[0][N-3-M:0] - (Q1[1][N-3-M:0] >> Q1[6]-1); // Subtract the mantissas
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sum[N-3-M:0] = res;
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end
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end
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- else if (~flag_a & flag_b)
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+ else if (~Q1[4] & Q1[5])
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begin
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// If the signs of both inputs are the same you add, otherwise you subtract
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- if (input_1[N-1] == input_2[N-1])
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+ if (Q1[0][N-1] == Q1[1][N-1])
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begin
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- res = (input_1[N-3-M:0] >> abs-1) + input_2[N-3-M:0]; // Sum the mantissa
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- sum[N-3-M:0] = res;
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+ Q1[7] = (Q1[0][N-3-M:0] >> Q1[6]-1) + Q1[1][N-3-M:0]; // Sum the mantissa
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+ Q1[2][N-3-M:0] = Q1[7];
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end
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else
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begin
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- res = input_2[N-3-M:0] - (input_1[N-3-M:0] >> abs-1); // Subtract the mantissas
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- sum[N-3-M:0] = res;
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+ Q1[7] = Q1[1][N-3-M:0] - (Q1[0][N-3-M:0] >> Q1[6]-1); // Subtract the mantissas
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+ Q1[2][N-3-M:0] = Q1[7];
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end
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end
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else
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begin
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- if (input_1[N-1] == input_2[N-1]) // If exponents and signs equal
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+ if (Q1[0][N-1] == Q1[1][N-1]) // If exponents and signs equal
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begin
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- res = input_1[N-3-M:0] + input_2[N-3-M:0]; // Sum the mantissa
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- sum[N-3-M:0] = res;
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+ Q1[7] = Q1[0][N-3-M:0] + Q1[1][N-3-M:0]; // Sum the mantissa
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+ Q1[2][N-3-M:0] = Q1[7];
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end
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else // In this case it will be a subtraction
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begin
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- if (input_1[N-3-M:0] > input_2[N-3-M:0]) // Which has the larger mantissa
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+ if (Q1[0][N-3-M:0] > Q1[1][N-3-M:0]) // Which has the larger mantissa
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begin
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- res = input_1[N-3-M:0] - input_2[N-3-M:0]; // Subtract the mantissa
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- sum[N-3-M:0] = res;
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+ Q1[7] = Q1[0][N-3-M:0] - Q1[1][N-3-M:0]; // Subtract the mantissa
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+ Q1[2][N-3-M:0] = Q1[7];
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end
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- else if (input_1[N-3-M:0] < input_2[N-3-M:0])
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+ else if (Q1[0][N-3-M:0] < Q1[1][N-3-M:0])
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begin
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- res = input_2[N-3-M:0] - input_1[N-3-M:0]; // Subtract the mantissa
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- sum[N-3-M:0] = res;
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+ Q1[7] = Q1[1][N-3-M:0] - Q1[0][N-3-M:0]; // Subtract the mantissa
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+ Q1[2][N-3-M:0] = Q1[7];
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end
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- else res = 0; // Both the exponent and the mantissa are equal so subtraction leads to 0
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- sum[N-3-M:0] = res;
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+ else Q1[7] = 0; // Both the exponent and the mantissa are equal so subtraction leads to 0
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+ Q1[2][N-3-M:0] = Q1[7];
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end
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end
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end
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end
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+
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+ // Final pipeline stage
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+ pipe pipe2(.clk(clk), .reset(reset), .D(Q1), .Q(Q2));
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+ assign sum = Q2[2];
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+ assign diff = Q2[3];
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endmodule : floating_add
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@@ -152,8 +181,8 @@ endmodule : floating_product
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module pipe #(parameter N=16)(clk, reset, Q, D);
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input logic clk, reset;
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- input logic [N-1:0] D [K:0];
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- output reg [N-1:0] Q [K:0];
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+ input logic [N-1:0] D;
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+ output reg [N-1:0] Q;
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reg [N-1:0] in_pipe;
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always @(posedge clk or negedge reset)
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@@ -211,4 +240,49 @@ module floating_tb;
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$display("Passed %d of %d tests", num_tests-num_err, num_tests);
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$finish();
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end
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-endmodule : floating_tb
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+endmodule : floating_tb
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+
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+
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+
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+module floating32_tb;
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+ reg reset, clk;
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+ logic [31:0] input_a, input_b, result_add, result_mult;
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+
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+ floating_add#(.N(32), .M(8)) add0(
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+ .input_1(input_a), .input_2(input_b), .sum(result_add), .diff()
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+ );
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+ floating_product#(.N(32), .M(8)) mult0(
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+ .input_1(input_a), .input_2(input_b), .product(result_mult)
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+ );
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+
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+ reg [31:0] test_mem [29:0][3:0];
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+
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+ initial $readmemh("scripts/fp32_test.hex", test_mem);
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+
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+
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+ initial begin
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+ static int num_err = 0;
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+ static int num_tests = $size(test_mem) * 2;
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+
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+ for (int i=0; i < $size(test_mem); i++) begin
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+ input_a = test_mem[i][0];
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+ input_b = test_mem[i][1];
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+
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+ #10;
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+ if(result_add != test_mem[i][2]) begin
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+ if(num_err < 20)
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+ $display("FAIL ADD: %H + %H = %H, expected %H", input_a, input_b, result_add, test_mem[i][2]);
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+ num_err = num_err + 1;
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+ end
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+
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+ if(result_mult != test_mem[i][3]) begin
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+ if(num_err < 20)
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+ $display("FAIL MULTIPLY: %H + %H = %H, expected %H", input_a, input_b, result_mult, test_mem[i][3]);
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+ num_err = num_err + 1;
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+ end
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+
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+ end
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+ $display("Passed %d of %d tests", num_tests-num_err, num_tests);
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+ $finish();
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+ end
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+endmodule : floating32_tb
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