URL https://opencores.org/ocsvn/openrisc/openrisc/trunk

Subversion Repositories openrisc

[/] [openrisc/] [trunk/] [or1200/] [rtl/] [verilog/] [or1200_fpu_post_norm_mul.v] - Blame information for rev 705

Go to most recent revision | Details | Compare with Previous | View Log


//////////////////////////////////////////////////////////////////////
////                                                              ////
////  or1200_fpu_post_norm_mul                                    ////
////                                                              ////
////  This file is part of the OpenRISC 1200 project              ////
////  http://opencores.org/project,or1k                           ////
////                                                              ////
////  Description                                                 ////
////  post-normalization entity for the multiplication unit       ////
////                                                              ////
////  To Do:                                                      ////
////                                                              ////
////                                                              ////
////  Author(s):                                                  ////
////      - Original design (FPU100) -                            ////
////        Jidan Al-eryani, jidan@gmx.net                        ////
////      - Conv. to Verilog and inclusion in OR1200 -            ////
////        Julius Baxter, julius@opencores.org                   ////
////                                                              ////
//////////////////////////////////////////////////////////////////////
//
//  Copyright (C) 2006, 2010
//
//      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. 
//
 
module or1200_fpu_post_norm_mul(
                     clk_i,
                     opa_i,
                     opb_i,
                     exp_10_i,
                     fract_48_i,
                     sign_i,
                     rmode_i,
                     output_o,
                     ine_o
                     );
 
   parameter FP_WIDTH = 32;
   parameter MUL_SERIAL = 0; // 0 for parallel multiplier, 1 for serial
   parameter MUL_COUNT = 11; //11 for parallel multiplier, 34 for serial
   parameter FRAC_WIDTH = 23;
   parameter EXP_WIDTH = 8;
   parameter ZERO_VECTOR = 31'd0;
   parameter INF = 31'b1111111100000000000000000000000;
   parameter QNAN = 31'b1111111110000000000000000000000;
   parameter SNAN = 31'b1111111100000000000000000000001;
 
   input clk_i;
   input [FP_WIDTH-1:0] opa_i;
   input [FP_WIDTH-1:0] opb_i;
   input [EXP_WIDTH+1:0] exp_10_i;
   input [2*FRAC_WIDTH+1:0] fract_48_i;
   input                    sign_i;
   input [1:0]               rmode_i;
   output reg [FP_WIDTH-1:0]    output_o;
   output reg               ine_o;
 
 
   reg [EXP_WIDTH-1:0]     s_expa;
   reg [EXP_WIDTH-1:0]     s_expb;
   reg [EXP_WIDTH+1:0]     s_exp_10_i;
   reg [2*FRAC_WIDTH+1:0]  s_fract_48_i;
   reg                     s_sign_i;
   wire [FP_WIDTH-1:0]       s_output_o;
   wire                     s_ine_o;
   wire                     s_overflow;
   reg [FP_WIDTH-1:0]        s_opa_i;
   reg [FP_WIDTH-1:0]        s_opb_i;
   reg [1:0]                 s_rmode_i;
 
   reg [5:0]                 s_zeros;
   wire                     s_carry;
   reg [5:0]                 s_shr2;
   reg [5:0]                 s_shl2;
   reg [8:0]                 s_expo1;
   wire [8:0]                s_expo2b;
   wire [9:0]                s_exp_10a;
   wire [9:0]                s_exp_10b;
   reg [47:0]                s_frac2a;
 
   wire                     s_sticky, s_guard, s_round;
   wire                     s_roundup;
   reg [24:0]                s_frac_rnd;
   wire [24:0]               s_frac3;
   wire                     s_shr3;
   reg [5:0]                 s_r_zeros;
   wire                     s_lost;
   wire                     s_op_0;
   wire [8:0]                s_expo3;
 
   wire                     s_infa, s_infb;
   wire                     s_nan_in, s_nan_op, s_nan_a, s_nan_b;
 
 
   // Input Register
   always @(posedge clk_i)
     begin
        s_opa_i <= opa_i;
        s_opb_i <= opb_i;
        s_expa <= opa_i[30:23];
        s_expb <= opb_i[30:23];
        s_exp_10_i <= exp_10_i;
        s_fract_48_i <= fract_48_i;
        s_sign_i <= sign_i;
        s_rmode_i <= rmode_i;
     end
 
   // Output register
   always @(posedge clk_i)
     begin
        output_o <= s_output_o;
        ine_o   <= s_ine_o;
     end
 
   //*** Stage 1 ****
   // figure out the exponent and howmuch the fraction has to be shiftd 
   // right/left
 
   assign s_carry = s_fract_48_i[47];
 
 
   always @(posedge clk_i)
     if (!s_fract_48_i[47])
       casez(s_fract_48_i[46:1])        // synopsys full_case parallel_case
         46'b1?????????????????????????????????????????????: s_zeros <=  0;
         46'b01????????????????????????????????????????????: s_zeros <=  1;
         46'b001???????????????????????????????????????????: s_zeros <=  2;
         46'b0001??????????????????????????????????????????: s_zeros <=  3;
         46'b00001?????????????????????????????????????????: s_zeros <=  4;
         46'b000001????????????????????????????????????????: s_zeros <=  5;
         46'b0000001???????????????????????????????????????: s_zeros <=  6;
         46'b00000001??????????????????????????????????????: s_zeros <=  7;
         46'b000000001?????????????????????????????????????: s_zeros <=  8;
         46'b0000000001????????????????????????????????????: s_zeros <=  9;
         46'b00000000001???????????????????????????????????: s_zeros <=  10;
         46'b000000000001??????????????????????????????????: s_zeros <=  11;
         46'b0000000000001?????????????????????????????????: s_zeros <=  12;
         46'b00000000000001????????????????????????????????: s_zeros <=  13;
         46'b000000000000001???????????????????????????????: s_zeros <=  14;
         46'b0000000000000001??????????????????????????????: s_zeros <=  15;
         46'b00000000000000001?????????????????????????????: s_zeros <=  16;
         46'b000000000000000001????????????????????????????: s_zeros <=  17;
         46'b0000000000000000001???????????????????????????: s_zeros <=  18;
         46'b00000000000000000001??????????????????????????: s_zeros <=  19;
         46'b000000000000000000001?????????????????????????: s_zeros <=  20;
         46'b0000000000000000000001????????????????????????: s_zeros <=  21;
         46'b00000000000000000000001???????????????????????: s_zeros <=  22;
         46'b000000000000000000000001??????????????????????: s_zeros <=  23;
         46'b0000000000000000000000001?????????????????????: s_zeros <=  24;
         46'b00000000000000000000000001????????????????????: s_zeros <=  25;
         46'b000000000000000000000000001???????????????????: s_zeros <=  26;
         46'b0000000000000000000000000001??????????????????: s_zeros <=  27;
         46'b00000000000000000000000000001?????????????????: s_zeros <=  28;
         46'b000000000000000000000000000001????????????????: s_zeros <=  29;
         46'b0000000000000000000000000000001???????????????: s_zeros <=  30;
         46'b00000000000000000000000000000001??????????????: s_zeros <=  31;
         46'b000000000000000000000000000000001?????????????: s_zeros <=  32;
         46'b0000000000000000000000000000000001????????????: s_zeros <=  33;
         46'b00000000000000000000000000000000001???????????: s_zeros <=  34;
         46'b000000000000000000000000000000000001??????????: s_zeros <=  35;
         46'b0000000000000000000000000000000000001?????????: s_zeros <=  36;
         46'b00000000000000000000000000000000000001????????: s_zeros <=  37;
         46'b000000000000000000000000000000000000001???????: s_zeros <=  38;
         46'b0000000000000000000000000000000000000001??????: s_zeros <=  39;
         46'b00000000000000000000000000000000000000001?????: s_zeros <=  40;
         46'b000000000000000000000000000000000000000001????: s_zeros <=  41;
         46'b0000000000000000000000000000000000000000001???: s_zeros <=  42;
         46'b00000000000000000000000000000000000000000001??: s_zeros <=  43;
         46'b000000000000000000000000000000000000000000001?: s_zeros <=  44;
         46'b0000000000000000000000000000000000000000000001: s_zeros <=  45;
         46'b0000000000000000000000000000000000000000000000: s_zeros <=  46;
       endcase // casex (s_fract_48_i[46:1])
     else
       s_zeros <= 0;
 
 
   always @(posedge clk_i)
     casez(s_fract_48_i) // synopsys full_case parallel_case
       48'b???????????????????????????????????????????????1: s_r_zeros <=  0;
       48'b??????????????????????????????????????????????10: s_r_zeros <=  1;
       48'b?????????????????????????????????????????????100: s_r_zeros <=  2;
       48'b????????????????????????????????????????????1000: s_r_zeros <=  3;
       48'b???????????????????????????????????????????10000: s_r_zeros <=  4;
       48'b??????????????????????????????????????????100000: s_r_zeros <=  5;
       48'b?????????????????????????????????????????1000000: s_r_zeros <=  6;
       48'b????????????????????????????????????????10000000: s_r_zeros <=  7;
       48'b???????????????????????????????????????100000000: s_r_zeros <=  8;
       48'b??????????????????????????????????????1000000000: s_r_zeros <=  9;
       48'b?????????????????????????????????????10000000000: s_r_zeros <=  10;
       48'b????????????????????????????????????100000000000: s_r_zeros <=  11;
       48'b???????????????????????????????????1000000000000: s_r_zeros <=  12;
       48'b??????????????????????????????????10000000000000: s_r_zeros <=  13;
       48'b?????????????????????????????????100000000000000: s_r_zeros <=  14;
       48'b????????????????????????????????1000000000000000: s_r_zeros <=  15;
       48'b???????????????????????????????10000000000000000: s_r_zeros <=  16;
       48'b??????????????????????????????100000000000000000: s_r_zeros <=  17;
       48'b?????????????????????????????1000000000000000000: s_r_zeros <=  18;
       48'b????????????????????????????10000000000000000000: s_r_zeros <=  19;
       48'b???????????????????????????100000000000000000000: s_r_zeros <=  20;
       48'b??????????????????????????1000000000000000000000: s_r_zeros <=  21;
       48'b?????????????????????????10000000000000000000000: s_r_zeros <=  22;
       48'b????????????????????????100000000000000000000000: s_r_zeros <=  23;
       48'b???????????????????????1000000000000000000000000: s_r_zeros <=  24;
       48'b??????????????????????10000000000000000000000000: s_r_zeros <=  25;
       48'b?????????????????????100000000000000000000000000: s_r_zeros <=  26;
       48'b????????????????????1000000000000000000000000000: s_r_zeros <=  27;
       48'b???????????????????10000000000000000000000000000: s_r_zeros <=  28;
       48'b??????????????????100000000000000000000000000000: s_r_zeros <=  29;
       48'b?????????????????1000000000000000000000000000000: s_r_zeros <=  30;
       48'b????????????????10000000000000000000000000000000: s_r_zeros <=  31;
       48'b???????????????100000000000000000000000000000000: s_r_zeros <=  32;
       48'b??????????????1000000000000000000000000000000000: s_r_zeros <=  33;
       48'b?????????????10000000000000000000000000000000000: s_r_zeros <=  34;
       48'b????????????100000000000000000000000000000000000: s_r_zeros <=  35;
       48'b???????????1000000000000000000000000000000000000: s_r_zeros <=  36;
       48'b??????????10000000000000000000000000000000000000: s_r_zeros <=  37;
       48'b?????????100000000000000000000000000000000000000: s_r_zeros <=  38;
       48'b????????1000000000000000000000000000000000000000: s_r_zeros <=  39;
       48'b???????10000000000000000000000000000000000000000: s_r_zeros <=  40;
       48'b??????100000000000000000000000000000000000000000: s_r_zeros <=  41;
       48'b?????1000000000000000000000000000000000000000000: s_r_zeros <=  42;
       48'b????10000000000000000000000000000000000000000000: s_r_zeros <=  43;
       48'b???100000000000000000000000000000000000000000000: s_r_zeros <=  44;
       48'b??1000000000000000000000000000000000000000000000: s_r_zeros <=  45;
       48'b?10000000000000000000000000000000000000000000000: s_r_zeros <=  46;
       48'b100000000000000000000000000000000000000000000000: s_r_zeros <=  47;
       48'b000000000000000000000000000000000000000000000000: s_r_zeros <=  48;
     endcase // casex (s_fract_48_i)
 
   assign s_exp_10a = s_exp_10_i + {9'd0,s_carry};
   assign s_exp_10b = s_exp_10a - {4'd0,s_zeros};
 
   wire [9:0] v_shr1;
   wire [9:0] v_shl1;
 
   assign v_shr1 = (s_exp_10a[9] | !(|s_exp_10a)) ?
                   10'd1 - s_exp_10a + {9'd0,s_carry} :
                   (s_exp_10b[9] | !(|s_exp_10b)) ?
 
                   s_exp_10b[8] ?
 
 
   assign v_shl1 = (s_exp_10a[9] | !(|s_exp_10a)) ?
 
                   (s_exp_10b[9] | !(|s_exp_10b)) ?
                   {4'd0,s_zeros} - s_exp_10a :
                   s_exp_10b[8] ?
 
 
 
   always @(posedge clk_i)
     begin
        if ((s_exp_10a[9] | !(|s_exp_10a)))
          s_expo1 <= 9'd1;
        else if (s_exp_10b[9] | !(|s_exp_10b))
          s_expo1 <= 9'd1;
        else if (s_exp_10b[8])
          s_expo1 <= 9'b011111111;
        else
          s_expo1 <= s_exp_10b[8:0];
 
        if (v_shr1[6])
          s_shr2 <= {6{1'b1}};
        else
          s_shr2 <= v_shr1[5:0];
 
        s_shl2 <= v_shl1[5:0];
     end // always @ (posedge clk_i)
 
   // *** Stage 2 ***
   // Shifting the fraction and rounding
 
 
   // shift the fraction
   always @(posedge clk_i)
     if (|s_shr2)
       s_frac2a <= s_fract_48_i >> s_shr2;
     else
       s_frac2a <= s_fract_48_i << s_shl2;
 
   assign s_expo2b = s_frac2a[46] ? s_expo1 : s_expo1 - 9'd1;
 
   // signals if precision was last during the right-shift above
   assign s_lost = (s_shr2 + {5'd0,s_shr3}) > s_r_zeros;
 
   // ***Stage 3***
   // Rounding
 
   //                                                              23
   //                                                                   |       
   //                   xx00000000000000000000000grsxxxxxxxxxxxxxxxxxxxx
   // guard bit: s_frac2a[23] (LSB of output)
   // round bit: s_frac2a[22]
   assign s_guard = s_frac2a[22];
   assign s_round = s_frac2a[21];
   assign s_sticky = (|s_frac2a[20:0]) | s_lost;
 
   assign s_roundup = s_rmode_i==2'b00 ? // round to nearest even
                      s_guard & ((s_round | s_sticky) | s_frac2a[23]) :
                      s_rmode_i==2'b10 ? // round up
                      (s_guard | s_round | s_sticky) & !s_sign_i :
                      s_rmode_i==2'b11 ? // round down
                      (s_guard | s_round | s_sticky) & s_sign_i :
                      0; // round to zero(truncate = no rounding)
 
 
   always @(posedge clk_i)
     if (s_roundup)
       s_frac_rnd <= s_frac2a[47:23] + 1;
     else
       s_frac_rnd <= s_frac2a[47:23];
 
   assign s_shr3 = s_frac_rnd[24];
 
 
   assign s_expo3 = (s_shr3 & (s_expo2b!=9'b011111111)) ?
                     s_expo2b + 1 : s_expo2b;
 
   assign s_frac3 = (s_shr3 & (s_expo2b!=9'b011111111)) ?
                     {1'b0,s_frac_rnd[24:1]} : s_frac_rnd;
 
   //-***Stage 4****
   // Output
 
   assign s_op_0 = !((|s_opa_i[30:0]) & (|s_opb_i[30:0]));
 
   assign s_infa = &s_expa;
 
   assign s_infb = &s_expb;
 
   assign s_nan_a = s_infa & (|s_opa_i[22:0]);
 
   assign s_nan_b = s_infb & (|s_opb_i[22:0]);
 
   assign s_nan_in = s_nan_a | s_nan_b;
 
   assign s_nan_op = (s_infa | s_infb) & s_op_0; // 0 * inf = nan
 
   assign s_overflow = (s_expo3==9'b011111111) & !(s_infa | s_infb);
 
   assign s_ine_o = !s_op_0 & (s_lost | (|s_frac2a[22:0]) | s_overflow);
 
   assign s_output_o = (s_nan_in | s_nan_op) ?
                       {s_sign_i,QNAN} :
                       (s_infa | s_infb) | s_overflow ?
                       {s_sign_i,INF} :
                       s_r_zeros==48 ?
                       {s_sign_i,ZERO_VECTOR} :
                       {s_sign_i,s_expo3[7:0],s_frac3[22:0]};
 
endmodule // or1200_fpu_post_norm_mul
 

Browse

Tools

Subversion Repositories openrisc

[/] [openrisc/] [trunk/] [or1200/] [rtl/] [verilog/] [or1200_fpu_post_norm_mul.v] - Blame information for rev 705

Line No.	Rev	Author	Line
1	258	julius	`//////////////////////////////////////////////////////////////////////`
2			`//// ////`
3			`//// or1200_fpu_post_norm_mul ////`
4			`//// ////`
5			`//// This file is part of the OpenRISC 1200 project ////`
6			`//// http://opencores.org/project,or1k ////`
7			`//// ////`
8			`//// Description ////`
9			`//// post-normalization entity for the multiplication unit ////`
10			`//// ////`
11			`//// To Do: ////`
12			`//// ////`
13			`//// ////`
14			`//// Author(s): ////`
15			`//// - Original design (FPU100) - ////`
16			`//// Jidan Al-eryani, jidan@gmx.net ////`
17			`//// - Conv. to Verilog and inclusion in OR1200 - ////`
18			`//// Julius Baxter, julius@opencores.org ////`
19			`//// ////`
20			`//////////////////////////////////////////////////////////////////////`
21			`//`
22			`// Copyright (C) 2006, 2010`
23			`//`
24			`// This source file may be used and distributed without`
25			`// restriction provided that this copyright statement is not`
26			`// removed from the file and that any derivative work contains`
27			`// the original copyright notice and the associated disclaimer.`
28			`//`
29			// THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY
30			`// EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED`
31			`// TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS`
32			`// FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL THE AUTHOR`
33			`// OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,`
34			`// INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES`
35			`// (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE`
36			`// GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR`
37			`// BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF`
38			`// LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT`
39			`// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT`
40			`// OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE`
41			`// POSSIBILITY OF SUCH DAMAGE.`
42			`//`
43
44			`module or1200_fpu_post_norm_mul(`
45			`clk_i,`
46			`opa_i,`
47			`opb_i,`
48			`exp_10_i,`
49			`fract_48_i,`
50			`sign_i,`
51			`rmode_i,`
52			`output_o,`
53			`ine_o`
54			`);`
55
56			`parameter FP_WIDTH = 32;`
57			`parameter MUL_SERIAL = 0; // 0 for parallel multiplier, 1 for serial`
58			`parameter MUL_COUNT = 11; //11 for parallel multiplier, 34 for serial`
59			`parameter FRAC_WIDTH = 23;`
60			`parameter EXP_WIDTH = 8;`
61			`parameter ZERO_VECTOR = 31'd0;`
62			`parameter INF = 31'b1111111100000000000000000000000;`
63			`parameter QNAN = 31'b1111111110000000000000000000000;`
64			`parameter SNAN = 31'b1111111100000000000000000000001;`
65
66			`input clk_i;`
67			`input [FP_WIDTH-1:0] opa_i;`
68			`input [FP_WIDTH-1:0] opb_i;`
69			`input [EXP_WIDTH+1:0] exp_10_i;`
70			`input [2*FRAC_WIDTH+1:0] fract_48_i;`
71			`input sign_i;`
72			`input [1:0] rmode_i;`
73			`output reg [FP_WIDTH-1:0] output_o;`
74			`output reg ine_o;`
75
76
77			`reg [EXP_WIDTH-1:0] s_expa;`
78			`reg [EXP_WIDTH-1:0] s_expb;`
79			`reg [EXP_WIDTH+1:0] s_exp_10_i;`
80			`reg [2*FRAC_WIDTH+1:0] s_fract_48_i;`
81			`reg s_sign_i;`
82			`wire [FP_WIDTH-1:0] s_output_o;`
83			`wire s_ine_o;`
84			`wire s_overflow;`
85			`reg [FP_WIDTH-1:0] s_opa_i;`
86			`reg [FP_WIDTH-1:0] s_opb_i;`
87			`reg [1:0] s_rmode_i;`
88
89			`reg [5:0] s_zeros;`
90			`wire s_carry;`
91			`reg [5:0] s_shr2;`
92			`reg [5:0] s_shl2;`
93			`reg [8:0] s_expo1;`
94			`wire [8:0] s_expo2b;`
95			`wire [9:0] s_exp_10a;`
96			`wire [9:0] s_exp_10b;`
97			`reg [47:0] s_frac2a;`
98
99			`wire s_sticky, s_guard, s_round;`
100			`wire s_roundup;`
101			`reg [24:0] s_frac_rnd;`
102			`wire [24:0] s_frac3;`
103			`wire s_shr3;`
104			`reg [5:0] s_r_zeros;`
105			`wire s_lost;`
106			`wire s_op_0;`
107			`wire [8:0] s_expo3;`
108
109			`wire s_infa, s_infb;`
110			`wire s_nan_in, s_nan_op, s_nan_a, s_nan_b;`
111
112
113			`// Input Register`
114			`always @(posedge clk_i)`
115			`begin`
116			`s_opa_i <= opa_i;`
117			`s_opb_i <= opb_i;`
118			`s_expa <= opa_i[30:23];`
119			`s_expb <= opb_i[30:23];`
120			`s_exp_10_i <= exp_10_i;`
121			`s_fract_48_i <= fract_48_i;`
122			`s_sign_i <= sign_i;`
123			`s_rmode_i <= rmode_i;`
124			`end`
125
126			`// Output register`
127			`always @(posedge clk_i)`
128			`begin`
129			`output_o <= s_output_o;`
130			`ine_o <= s_ine_o;`
131			`end`
132
133			`//* Stage 1 **`
134			`// figure out the exponent and howmuch the fraction has to be shiftd`
135			`// right/left`
136
137			`assign s_carry = s_fract_48_i[47];`
138
139
140			`always @(posedge clk_i)`
141			`if (!s_fract_48_i[47])`
142	364	julius	`casez(s_fract_48_i[46:1]) // synopsys full_case parallel_case`
143	258	julius	`46'b1?????????????????????????????????????????????: s_zeros <= 0;`
144			`46'b01????????????????????????????????????????????: s_zeros <= 1;`
145			`46'b001???????????????????????????????????????????: s_zeros <= 2;`
146			`46'b0001??????????????????????????????????????????: s_zeros <= 3;`
147			`46'b00001?????????????????????????????????????????: s_zeros <= 4;`
148			`46'b000001????????????????????????????????????????: s_zeros <= 5;`
149			`46'b0000001???????????????????????????????????????: s_zeros <= 6;`
150			`46'b00000001??????????????????????????????????????: s_zeros <= 7;`
151			`46'b000000001?????????????????????????????????????: s_zeros <= 8;`
152			`46'b0000000001????????????????????????????????????: s_zeros <= 9;`
153			`46'b00000000001???????????????????????????????????: s_zeros <= 10;`
154			`46'b000000000001??????????????????????????????????: s_zeros <= 11;`
155			`46'b0000000000001?????????????????????????????????: s_zeros <= 12;`
156			`46'b00000000000001????????????????????????????????: s_zeros <= 13;`
157			`46'b000000000000001???????????????????????????????: s_zeros <= 14;`
158			`46'b0000000000000001??????????????????????????????: s_zeros <= 15;`
159			`46'b00000000000000001?????????????????????????????: s_zeros <= 16;`
160			`46'b000000000000000001????????????????????????????: s_zeros <= 17;`
161			`46'b0000000000000000001???????????????????????????: s_zeros <= 18;`
162			`46'b00000000000000000001??????????????????????????: s_zeros <= 19;`
163			`46'b000000000000000000001?????????????????????????: s_zeros <= 20;`
164			`46'b0000000000000000000001????????????????????????: s_zeros <= 21;`
165			`46'b00000000000000000000001???????????????????????: s_zeros <= 22;`
166			`46'b000000000000000000000001??????????????????????: s_zeros <= 23;`
167			`46'b0000000000000000000000001?????????????????????: s_zeros <= 24;`
168			`46'b00000000000000000000000001????????????????????: s_zeros <= 25;`
169			`46'b000000000000000000000000001???????????????????: s_zeros <= 26;`
170			`46'b0000000000000000000000000001??????????????????: s_zeros <= 27;`
171			`46'b00000000000000000000000000001?????????????????: s_zeros <= 28;`
172			`46'b000000000000000000000000000001????????????????: s_zeros <= 29;`
173			`46'b0000000000000000000000000000001???????????????: s_zeros <= 30;`
174			`46'b00000000000000000000000000000001??????????????: s_zeros <= 31;`
175			`46'b000000000000000000000000000000001?????????????: s_zeros <= 32;`
176			`46'b0000000000000000000000000000000001????????????: s_zeros <= 33;`
177			`46'b00000000000000000000000000000000001???????????: s_zeros <= 34;`
178			`46'b000000000000000000000000000000000001??????????: s_zeros <= 35;`
179			`46'b0000000000000000000000000000000000001?????????: s_zeros <= 36;`
180			`46'b00000000000000000000000000000000000001????????: s_zeros <= 37;`
181			`46'b000000000000000000000000000000000000001???????: s_zeros <= 38;`
182			`46'b0000000000000000000000000000000000000001??????: s_zeros <= 39;`
183			`46'b00000000000000000000000000000000000000001?????: s_zeros <= 40;`
184			`46'b000000000000000000000000000000000000000001????: s_zeros <= 41;`
185			`46'b0000000000000000000000000000000000000000001???: s_zeros <= 42;`
186			`46'b00000000000000000000000000000000000000000001??: s_zeros <= 43;`
187			`46'b000000000000000000000000000000000000000000001?: s_zeros <= 44;`
188			`46'b0000000000000000000000000000000000000000000001: s_zeros <= 45;`
189			`46'b0000000000000000000000000000000000000000000000: s_zeros <= 46;`
190			`endcase // casex (s_fract_48_i[46:1])`
191			`else`
192			`s_zeros <= 0;`
193
194
195			`always @(posedge clk_i)`
196	364	julius	`casez(s_fract_48_i) // synopsys full_case parallel_case`
197	258	julius	`48'b???????????????????????????????????????????????1: s_r_zeros <= 0;`
198			`48'b??????????????????????????????????????????????10: s_r_zeros <= 1;`
199			`48'b?????????????????????????????????????????????100: s_r_zeros <= 2;`
200			`48'b????????????????????????????????????????????1000: s_r_zeros <= 3;`
201			`48'b???????????????????????????????????????????10000: s_r_zeros <= 4;`
202			`48'b??????????????????????????????????????????100000: s_r_zeros <= 5;`
203			`48'b?????????????????????????????????????????1000000: s_r_zeros <= 6;`
204			`48'b????????????????????????????????????????10000000: s_r_zeros <= 7;`
205			`48'b???????????????????????????????????????100000000: s_r_zeros <= 8;`
206			`48'b??????????????????????????????????????1000000000: s_r_zeros <= 9;`
207			`48'b?????????????????????????????????????10000000000: s_r_zeros <= 10;`
208			`48'b????????????????????????????????????100000000000: s_r_zeros <= 11;`
209			`48'b???????????????????????????????????1000000000000: s_r_zeros <= 12;`
210			`48'b??????????????????????????????????10000000000000: s_r_zeros <= 13;`
211			`48'b?????????????????????????????????100000000000000: s_r_zeros <= 14;`
212			`48'b????????????????????????????????1000000000000000: s_r_zeros <= 15;`
213			`48'b???????????????????????????????10000000000000000: s_r_zeros <= 16;`
214			`48'b??????????????????????????????100000000000000000: s_r_zeros <= 17;`
215			`48'b?????????????????????????????1000000000000000000: s_r_zeros <= 18;`
216			`48'b????????????????????????????10000000000000000000: s_r_zeros <= 19;`
217			`48'b???????????????????????????100000000000000000000: s_r_zeros <= 20;`
218			`48'b??????????????????????????1000000000000000000000: s_r_zeros <= 21;`
219			`48'b?????????????????????????10000000000000000000000: s_r_zeros <= 22;`
220			`48'b????????????????????????100000000000000000000000: s_r_zeros <= 23;`
221			`48'b???????????????????????1000000000000000000000000: s_r_zeros <= 24;`
222			`48'b??????????????????????10000000000000000000000000: s_r_zeros <= 25;`
223			`48'b?????????????????????100000000000000000000000000: s_r_zeros <= 26;`
224			`48'b????????????????????1000000000000000000000000000: s_r_zeros <= 27;`
225			`48'b???????????????????10000000000000000000000000000: s_r_zeros <= 28;`
226			`48'b??????????????????100000000000000000000000000000: s_r_zeros <= 29;`
227			`48'b?????????????????1000000000000000000000000000000: s_r_zeros <= 30;`
228			`48'b????????????????10000000000000000000000000000000: s_r_zeros <= 31;`
229			`48'b???????????????100000000000000000000000000000000: s_r_zeros <= 32;`
230			`48'b??????????????1000000000000000000000000000000000: s_r_zeros <= 33;`
231			`48'b?????????????10000000000000000000000000000000000: s_r_zeros <= 34;`
232			`48'b????????????100000000000000000000000000000000000: s_r_zeros <= 35;`
233			`48'b???????????1000000000000000000000000000000000000: s_r_zeros <= 36;`
234			`48'b??????????10000000000000000000000000000000000000: s_r_zeros <= 37;`
235			`48'b?????????100000000000000000000000000000000000000: s_r_zeros <= 38;`
236			`48'b????????1000000000000000000000000000000000000000: s_r_zeros <= 39;`
237			`48'b???????10000000000000000000000000000000000000000: s_r_zeros <= 40;`
238			`48'b??????100000000000000000000000000000000000000000: s_r_zeros <= 41;`
239			`48'b?????1000000000000000000000000000000000000000000: s_r_zeros <= 42;`
240			`48'b????10000000000000000000000000000000000000000000: s_r_zeros <= 43;`
241			`48'b???100000000000000000000000000000000000000000000: s_r_zeros <= 44;`
242			`48'b??1000000000000000000000000000000000000000000000: s_r_zeros <= 45;`
243			`48'b?10000000000000000000000000000000000000000000000: s_r_zeros <= 46;`
244			`48'b100000000000000000000000000000000000000000000000: s_r_zeros <= 47;`
245			`48'b000000000000000000000000000000000000000000000000: s_r_zeros <= 48;`
246			`endcase // casex (s_fract_48_i)`
247
248			`assign s_exp_10a = s_exp_10_i + {9'd0,s_carry};`
249			`assign s_exp_10b = s_exp_10a - {4'd0,s_zeros};`
250
251			`wire [9:0] v_shr1;`
252			`wire [9:0] v_shl1;`
253
254			`assign v_shr1 = (s_exp_10a[9] \| !(\|s_exp_10a)) ?`
255			`10'd1 - s_exp_10a + {9'd0,s_carry} :`
256			`(s_exp_10b[9] \| !(\|s_exp_10b)) ?`
257
258			`s_exp_10b[8] ?`
259
260
261			`assign v_shl1 = (s_exp_10a[9] \| !(\|s_exp_10a)) ?`
262
263			`(s_exp_10b[9] \| !(\|s_exp_10b)) ?`
264			`{4'd0,s_zeros} - s_exp_10a :`
265			`s_exp_10b[8] ?`
266
267
268
269			`always @(posedge clk_i)`
270			`begin`
271			`if ((s_exp_10a[9] \| !(\|s_exp_10a)))`
272			`s_expo1 <= 9'd1;`
273			`else if (s_exp_10b[9] \| !(\|s_exp_10b))`
274	364	julius	`s_expo1 <= 9'd1;`
275	258	julius	`else if (s_exp_10b[8])`
276			`s_expo1 <= 9'b011111111;`
277			`else`
278			`s_expo1 <= s_exp_10b[8:0];`
279
280			`if (v_shr1[6])`
281			`s_shr2 <= {6{1'b1}};`
282			`else`
283			`s_shr2 <= v_shr1[5:0];`
284
285			`s_shl2 <= v_shl1[5:0];`
286			`end // always @ (posedge clk_i)`
287
288			`// * Stage 2 *`
289			`// Shifting the fraction and rounding`
290
291
292			`// shift the fraction`
293			`always @(posedge clk_i)`
294			`if (\|s_shr2)`
295			`s_frac2a <= s_fract_48_i >> s_shr2;`
296			`else`
297			`s_frac2a <= s_fract_48_i << s_shl2;`
298
299			`assign s_expo2b = s_frac2a[46] ? s_expo1 : s_expo1 - 9'd1;`
300
301			`// signals if precision was last during the right-shift above`
302			`assign s_lost = (s_shr2 + {5'd0,s_shr3}) > s_r_zeros;`
303
304			`// *Stage 3*`
305			`// Rounding`
306
307			`// 23`
308			`// \|`
309			`// xx00000000000000000000000grsxxxxxxxxxxxxxxxxxxxx`
310			`// guard bit: s_frac2a[23] (LSB of output)`
311			`// round bit: s_frac2a[22]`
312			`assign s_guard = s_frac2a[22];`
313			`assign s_round = s_frac2a[21];`
314			`assign s_sticky = (\|s_frac2a[20:0]) \| s_lost;`
315
316			`assign s_roundup = s_rmode_i==2'b00 ? // round to nearest even`
317			`s_guard & ((s_round \| s_sticky) \| s_frac2a[23]) :`
318			`s_rmode_i==2'b10 ? // round up`
319			`(s_guard \| s_round \| s_sticky) & !s_sign_i :`
320			`s_rmode_i==2'b11 ? // round down`
321			`(s_guard \| s_round \| s_sticky) & s_sign_i :`
322			`0; // round to zero(truncate = no rounding)`
323
324
325			`always @(posedge clk_i)`
326			`if (s_roundup)`
327			`s_frac_rnd <= s_frac2a[47:23] + 1;`
328			`else`
329			`s_frac_rnd <= s_frac2a[47:23];`
330
331			`assign s_shr3 = s_frac_rnd[24];`
332
333
334			`assign s_expo3 = (s_shr3 & (s_expo2b!=9'b011111111)) ?`
335			`s_expo2b + 1 : s_expo2b;`
336
337			`assign s_frac3 = (s_shr3 & (s_expo2b!=9'b011111111)) ?`
338			`{1'b0,s_frac_rnd[24:1]} : s_frac_rnd;`
339
340			`//-*Stage 4**`
341			`// Output`
342
343			`assign s_op_0 = !((\|s_opa_i[30:0]) & (\|s_opb_i[30:0]));`
344
345			`assign s_infa = &s_expa;`
346
347			`assign s_infb = &s_expb;`
348
349			`assign s_nan_a = s_infa & (\|s_opa_i[22:0]);`
350
351			`assign s_nan_b = s_infb & (\|s_opb_i[22:0]);`
352
353			`assign s_nan_in = s_nan_a \| s_nan_b;`
354
355			`assign s_nan_op = (s_infa \| s_infb) & s_op_0; // 0 * inf = nan`
356
357			`assign s_overflow = (s_expo3==9'b011111111) & !(s_infa \| s_infb);`
358
359			`assign s_ine_o = !s_op_0 & (s_lost \| (\|s_frac2a[22:0]) \| s_overflow);`
360
361			`assign s_output_o = (s_nan_in \| s_nan_op) ?`
362			`{s_sign_i,QNAN} :`
363			`(s_infa \| s_infb) \| s_overflow ?`
364			`{s_sign_i,INF} :`
365			`s_r_zeros==48 ?`
366			`{s_sign_i,ZERO_VECTOR} :`
367			`{s_sign_i,s_expo3[7:0],s_frac3[22:0]};`
368
369			`endmodule // or1200_fpu_post_norm_mul`
370