Subversion Repositories theia_gpu

`timescale 1ns / 1ps

`include "aDefinitions.v"

//------------------------------------------------------------------

module ArithmeticComparison

(

        input wire                                      Clock,

        input wire[`WIDTH-1:0]   X,Y,

        input wire[2:0]                  iOperation,

        input wire                                      iInputReady,

        output reg                                      OutputReady,

        output reg                                      Result

);

wire [`WIDTH-1:0] wX,wY;

wire SignX,SignY;

reg rGreaterThan;

wire wUGt,wULT,wEQ;

assign SignX = (X == 0) ? 0: X[31];

assign SignY = (Y == 0) ? 0: Y[31];

assign wX = ( SignX ) ? ~X + 1'b1 : X;

assign wY = ( SignY ) ? ~Y + 1'b1 : Y;

assign wUGt = wX > wY;

assign wULT = wX < wY;

assign wEQ = wX == wY;

always @ ( * )

begin

        case ( {SignX,SignY} )

                //Greater than test ( X > Y )

                2'b00: rGreaterThan = wUGt;             //both numbers positive

                2'b01: rGreaterThan = 1;                        //X positive, y negative        

                2'b10: rGreaterThan = 0;                 //X negative, y positive

                2'b11: rGreaterThan = wULT;             //X negative, y negative

        endcase

end

always @ ( posedge Clock )

begin

if (iInputReady)

begin

        case ( iOperation )

                3'b000: Result = rGreaterThan;                  //X > Y

                3'b001: Result = ~rGreaterThan;                 //X < Y

                3'b010: Result = wEQ;                                           //X == Y

                3'b011: Result = ~wEQ;                                          //X != Y

                3'b100: Result = rGreaterThan || wEQ;   // X >= Y

                3'b101: Result = ~rGreaterThan || wEQ; // X <= Y

                default: Result = 0;

        endcase

                OutputReady = 1;

end

else

                OutputReady = 0;

end

endmodule

//---------------------------------------------