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/////////////////////////////////////////////////////////////////////

////                                                             ////

////  or1200_fpu_intfloat_conv_except                            ////

////                                                             ////

////  Author: Rudolf Usselmann                                   ////

////          rudi@asics.ws                                      ////

////                                                             ////

//// Modified by Julius Baxter, July, 2010                       ////

////             julius.baxter@orsoc.se                          ////

////                                                             ////

////                                                             ////

/////////////////////////////////////////////////////////////////////

////                                                             ////

//// Copyright (C) 2000 Rudolf Usselmann                         ////

////                    rudi@asics.ws                            ////

////                                                             ////

//// This source file may be used and distributed without        ////

//// restriction provided that this copyright statement is not   ////

//// removed from the file and that any derivative work contains ////

//// the original copyright notice and the associated disclaimer.////

////                                                             ////

////     THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY     ////

//// EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED   ////

//// TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS   ////

//// FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL THE AUTHOR      ////

//// OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,         ////

//// INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES    ////

//// (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE   ////

//// GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR        ////

//// BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF  ////

//// LIABILITY, WHETHER IN  CONTRACT, STRICT LIABILITY, OR TORT  ////

//// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT  ////

//// OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE         ////

//// POSSIBILITY OF SUCH DAMAGE.                                 ////

////                                                             ////

/////////////////////////////////////////////////////////////////////

`timescale 1ns / 100ps

module or1200_fpu_intfloat_conv_except

  (

        clk, opa, opb, inf, ind, qnan, snan, opa_nan, opb_nan,

        opa_00, opb_00, opa_inf, opb_inf, opa_dn, opb_dn

        );

   input                clk;

   input [31:0]  opa, opb;

   output               inf, ind, qnan, snan, opa_nan, opb_nan;

   output               opa_00, opb_00;

   output               opa_inf, opb_inf;

   output               opa_dn;

   output               opb_dn;

   ////////////////////////////////////////////////////////////////////////

   //

   // Local Wires and registers

   //

   wire [7:0]            expa, expb;             // alias to opX exponent

   wire [22:0]           fracta, fractb;         // alias to opX fraction

   reg                  expa_ff, infa_f_r, qnan_r_a, snan_r_a;

   reg                  expb_ff, infb_f_r, qnan_r_b, snan_r_b;

   reg                  inf, ind, qnan, snan;   // Output registers

   reg                  opa_nan, opb_nan;

   reg                  expa_00, expb_00, fracta_00, fractb_00;

   reg                  opa_00, opb_00;

   reg                  opa_inf, opb_inf;

   reg                  opa_dn, opb_dn;

   ////////////////////////////////////////////////////////////////////////

   //

   // Aliases

   //

   assign   expa = opa[30:23];

   assign   expb = opb[30:23];

   assign fracta = opa[22:0];

   assign fractb = opb[22:0];

   ////////////////////////////////////////////////////////////////////////

   //

   // Determine if any of the input operators is a INF or NAN or any other 

   // special number

   //

   always @(posedge clk)

     expa_ff <=  &expa;

   always @(posedge clk)

     expb_ff <=  &expb;

   always @(posedge clk)

     infa_f_r <=  !(|fracta);

   always @(posedge clk)

     infb_f_r <=  !(|fractb);

   always @(posedge clk)

     qnan_r_a <=   fracta[22];

   always @(posedge clk)

     snan_r_a <=  !fracta[22] & |fracta[21:0];

   always @(posedge clk)

     qnan_r_b <=   fractb[22];

   always @(posedge clk)

     snan_r_b <=  !fractb[22]; // & |fractb[21:0];

   always @(posedge clk)

     ind  <=  (expa_ff & infa_f_r); // & (expb_ff & infb_f_r);

   always @(posedge clk)

     inf  <=  (expa_ff & infa_f_r); // | (expb_ff & infb_f_r);

   always @(posedge clk)

     qnan <=  (expa_ff & qnan_r_a); // | (expb_ff & qnan_r_b);

   always @(posedge clk)

     snan <=  (expa_ff & snan_r_a); // | (expb_ff & snan_r_b);

   always @(posedge clk)

     opa_nan <=  &expa & (|fracta[22:0]);

   always @(posedge clk)

     opb_nan <=  &expb & (|fractb[22:0]);

   always @(posedge clk)

     opa_inf <=  (expa_ff & infa_f_r);

   always @(posedge clk)

     opb_inf <=  (expb_ff & infb_f_r);

   always @(posedge clk)

     expa_00 <=  !(|expa);

   always @(posedge clk)

     expb_00 <=  !(|expb);

   always @(posedge clk)

     fracta_00 <=  !(|fracta);

   always @(posedge clk)

     fractb_00 <=  !(|fractb);

   always @(posedge clk)

     opa_00 <=  expa_00 & fracta_00;

   always @(posedge clk)

     opb_00 <=  expb_00 & fractb_00;

   always @(posedge clk)

     opa_dn <=  expa_00;

   always @(posedge clk)

     opb_dn <=  expb_00;

endmodule // or1200_fpu_intfloat_conv_except