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Line 1... |
`timescale 1ns / 1ps
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`timescale 1ns / 1ps
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// ============================================================================
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// ============================================================================
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// __
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// __
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// \\__/ o\ (C) 2006-2016 Robert Finch, Waterloo
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// \\__/ o\ (C) 2006-2018 Robert Finch, Waterloo
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// \ __ / All rights reserved.
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// \ __ / All rights reserved.
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// \/_// robfinch<remove>@finitron.ca
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// \/_// robfinch<remove>@finitron.ca
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// ||
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// ||
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//
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//
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// fpRound.v
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// fpRound.v
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Line 33... |
localparam EMSB = WID==128 ? 14 :
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localparam EMSB = WID==128 ? 14 :
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WID==96 ? 14 :
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WID==96 ? 14 :
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WID==80 ? 14 :
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WID==80 ? 14 :
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WID==64 ? 10 :
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WID==64 ? 10 :
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WID==52 ? 10 :
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WID==52 ? 10 :
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WID==48 ? 10 :
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WID==48 ? 11 :
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WID==44 ? 10 :
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WID==44 ? 10 :
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WID==42 ? 10 :
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WID==42 ? 10 :
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WID==40 ? 9 :
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WID==40 ? 9 :
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WID==32 ? 7 :
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WID==32 ? 7 :
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WID==24 ? 6 : 4;
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WID==24 ? 6 : 4;
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localparam FMSB = WID==128 ? 111 :
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localparam FMSB = WID==128 ? 111 :
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WID==96 ? 79 :
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WID==96 ? 79 :
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WID==80 ? 63 :
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WID==80 ? 63 :
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WID==64 ? 51 :
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WID==64 ? 51 :
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WID==52 ? 39 :
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WID==52 ? 39 :
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WID==48 ? 35 :
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WID==48 ? 34 :
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WID==44 ? 31 :
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WID==44 ? 31 :
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WID==42 ? 29 :
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WID==42 ? 29 :
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WID==40 ? 28 :
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WID==40 ? 28 :
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WID==32 ? 22 :
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WID==32 ? 22 :
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WID==24 ? 15 : 9;
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WID==24 ? 15 : 9;
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Line 94... |
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assign so = i[MSB+3];
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assign so = i[MSB+3];
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assign xo = rounded[MSB:FMSB+2];
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assign xo = rounded[MSB:FMSB+2];
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always @(rnd or xo or carry or dn or rounded or mo1)
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always @(rnd or xo or carry or dn or rounded or mo1)
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casex({rnd,&xo,carry,dn})
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casez({rnd,&xo,carry,dn})
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4'b0xx0: mo = mo1[FMSB+2:2]; // not rounding, not denormalized, => hide MSB
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4'b0??0: mo = mo1[FMSB+2:2]; // not rounding, not denormalized, => hide MSB
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4'b0xx1: mo = mo1[FMSB+3:3]; // not rounding, denormalized
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4'b0??1: mo = mo1[FMSB+3:3]; // not rounding, denormalized
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4'b1000: mo = rounded[FMSB :0]; // exponent didn't change, number was normalized, => hide MSB
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4'b1000: mo = rounded[FMSB :0]; // exponent didn't change, number was normalized, => hide MSB
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4'b1001: mo = rounded[FMSB+1:1]; // exponent didn't change, but number was denormalized, => retain MSB
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4'b1001: mo = rounded[FMSB+1:1]; // exponent didn't change, but number was denormalized, => retain MSB
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4'b1010: mo = rounded[FMSB+1:1]; // exponent incremented (new MSB generated), number was normalized, => hide 'extra (FMSB+2)' MSB
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4'b1010: mo = rounded[FMSB+1:1]; // exponent incremented (new MSB generated), number was normalized, => hide 'extra (FMSB+2)' MSB
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4'b1011: mo = rounded[FMSB+1:1]; // exponent incremented (new MSB generated), number was denormalized, number became normalized, => hide 'extra (FMSB+2)' MSB
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4'b1011: mo = rounded[FMSB+1:1]; // exponent incremented (new MSB generated), number was denormalized, number became normalized, => hide 'extra (FMSB+2)' MSB
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4'b11xx: mo = 0; // number became infinite, no need to check carry etc., rnd would be zero if input was NaN or infinite
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4'b11??: mo = 0; // number became infinite, no need to check carry etc., rnd would be zero if input was NaN or infinite
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endcase
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endcase
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endmodule
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endmodule
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| Line 117... |
Line 117... |
localparam EMSB = WID==128 ? 14 :
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localparam EMSB = WID==128 ? 14 :
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WID==96 ? 14 :
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WID==96 ? 14 :
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WID==80 ? 14 :
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WID==80 ? 14 :
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WID==64 ? 10 :
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WID==64 ? 10 :
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WID==52 ? 10 :
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WID==52 ? 10 :
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WID==48 ? 10 :
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WID==48 ? 11 :
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WID==44 ? 10 :
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WID==44 ? 10 :
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WID==42 ? 10 :
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WID==42 ? 10 :
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WID==40 ? 9 :
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WID==40 ? 9 :
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WID==32 ? 7 :
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WID==32 ? 7 :
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WID==24 ? 6 : 4;
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WID==24 ? 6 : 4;
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localparam FMSB = WID==128 ? 111 :
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localparam FMSB = WID==128 ? 111 :
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WID==96 ? 79 :
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WID==96 ? 79 :
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WID==80 ? 63 :
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WID==80 ? 63 :
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WID==64 ? 51 :
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WID==64 ? 51 :
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WID==52 ? 39 :
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WID==52 ? 39 :
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WID==48 ? 35 :
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WID==48 ? 34 :
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WID==44 ? 31 :
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WID==44 ? 31 :
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WID==42 ? 29 :
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WID==42 ? 29 :
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WID==40 ? 28 :
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WID==40 ? 28 :
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WID==32 ? 22 :
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WID==32 ? 22 :
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WID==24 ? 15 : 9;
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WID==24 ? 15 : 9;
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