//--------------------------------------------------------------------------------------------------// Design    : nova// Author(s) : Ke Xu// Email	   : eexuke@yahoo.com// File      : NumCoeffTrailingOnes_decoding.v// Generated : June 8, 2005// Copyright (C) 2008 Ke Xu                //-------------------------------------------------------------------------------------------------// Description // Decoding for Table 9-5 on Page159 of H.264/AVC standard 2003//-------------------------------------------------------------------------------------------------// synopsys translate_off`include "timescale.v"// synopsys translate_on`include "nova_defines.v"module NumCoeffTrailingOnes_decoding (clk,reset_n,cavlc_decoder_state,heading_one_pos,BitStream_buffer_output,	nC,TrailingOnes,TotalCoeff,NumCoeffTrailingOnes_len);	input clk,reset_n;	input [3:0] cavlc_decoder_state;	input [3:0] heading_one_pos;	input [15:0] BitStream_buffer_output;	input [4:0] nC;	output [1:0] TrailingOnes;	output [4:0] TotalCoeff;	output [4:0] NumCoeffTrailingOnes_len;	reg [1:0] TrailingOnes;	reg [4:0] TotalCoeff;	reg [4:0] NumCoeffTrailingOnes_len;			reg [1:0] TrailingOnes_reg;	reg [4:0] TotalCoeff_reg;		wire nC_0to2,nC_2to4,nC_4to8,nC_n1,nC_GE8;	wire nC_0to2_t0,nC_0to2_t1,nC_0to2_t2,nC_0to2_t3;	wire nC_2to4_t0,nC_2to4_t1,nC_2to4_t2,nC_2to4_t3;	wire nC_4to8_t0,nC_4to8_t1;	wire nC_n1_t0;	//Select nC values to choose table	assign nC_0to2 = (cavlc_decoder_state == `NumCoeffTrailingOnes_LUT && (nC == 5'd0 || nC == 5'd1));	assign nC_2to4 = (cavlc_decoder_state == `NumCoeffTrailingOnes_LUT && (nC == 5'd2 || nC == 5'd3));	assign nC_4to8 = (cavlc_decoder_state == `NumCoeffTrailingOnes_LUT && (nC == 5'd4 || nC == 5'd5 || nC == 5'd6 || nC == 5'd7));	assign nC_n1   = (cavlc_decoder_state == `NumCoeffTrailingOnes_LUT && (nC == 5'd31));	assign nC_GE8  = (cavlc_decoder_state == `NumCoeffTrailingOnes_LUT && !nC_0to2 && !nC_2to4 && !nC_4to8 && !nC_n1);		//1.nC_0to2 t0 ~ t4	sub-table selection	assign nC_0to2_t0 = (nC_0to2 && (heading_one_pos == 4'd0 || heading_one_pos == 4'd1 || heading_one_pos == 4'd2));	assign nC_0to2_t1 = (nC_0to2 && (heading_one_pos == 4'd3 || heading_one_pos == 4'd4));	assign nC_0to2_t2 = (nC_0to2 && (heading_one_pos == 4'd5 || heading_one_pos == 4'd6 || heading_one_pos == 4'd7 || heading_one_pos == 4'd8));	assign nC_0to2_t3 = (nC_0to2 && (heading_one_pos == 4'd9 || heading_one_pos == 4'd10));	//2.nC_2to4 t0 ~ t4	sub-table selection	assign nC_2to4_t0 = (nC_2to4 && (heading_one_pos == 4'd0 || heading_one_pos == 4'd1));	assign nC_2to4_t1 = (nC_2to4 && (heading_one_pos == 4'd2 || heading_one_pos == 4'd3));	assign nC_2to4_t2 = (nC_2to4 && (heading_one_pos == 4'd4 || heading_one_pos == 4'd5 || heading_one_pos == 4'd6));	assign nC_2to4_t3 = (nC_2to4 && (heading_one_pos == 4'd7 || heading_one_pos == 4'd8));	//3.nC_4to8 t0 ~ t2	sub-table selection 	assign nC_4to8_t0 = (nC_4to8 && heading_one_pos == 4'd0);	assign nC_4to8_t1 = (nC_4to8 && (heading_one_pos == 4'd1 || heading_one_pos == 4'd2 || heading_one_pos == 4'd3 || heading_one_pos == 4'd4));	//4.nC_GE8:single table, NO sub-table selection	//5.nC_n1 t0 ~ t1 sub-table selection	assign nC_n1_t0 = (nC_n1 && (heading_one_pos == 4'd0 || heading_one_pos == 4'd1 || heading_one_pos == 4'd2));		//NumCoeffTrailingOnes_len	always @ (nC_0to2 or nC_2to4 or nC_4to8 or nC_GE8 or nC_n1 or heading_one_pos or BitStream_buffer_output)		if (nC_0to2)			case (heading_one_pos)				0 :NumCoeffTrailingOnes_len <= 5'd1;				1 :NumCoeffTrailingOnes_len <= 5'd2;				2 :NumCoeffTrailingOnes_len <= 5'd3;				3 :NumCoeffTrailingOnes_len <= (BitStream_buffer_output[11] == 1)? 5'd5:5'd6;				4 :NumCoeffTrailingOnes_len <= (BitStream_buffer_output[10] == 1)? 5'd6:5'd7;				5 :NumCoeffTrailingOnes_len <= 5'd8;				6 :NumCoeffTrailingOnes_len <= 5'd9;				7 :NumCoeffTrailingOnes_len <= 5'd10;				8 :NumCoeffTrailingOnes_len <= 5'd11;				9 :NumCoeffTrailingOnes_len <= 5'd13;				10:NumCoeffTrailingOnes_len <= 5'd14;				11:NumCoeffTrailingOnes_len <= 5'd15;				12:NumCoeffTrailingOnes_len <= 5'd16;				13:NumCoeffTrailingOnes_len <= 5'd16;				14:NumCoeffTrailingOnes_len <= 5'd15;				default:NumCoeffTrailingOnes_len <= 5'd0;			endcase		else if (nC_2to4)			case (heading_one_pos)				0 :NumCoeffTrailingOnes_len <= 5'd2;				1 :NumCoeffTrailingOnes_len <= (BitStream_buffer_output[13] == 1)? 5'd3:5'd4;				2 :NumCoeffTrailingOnes_len <= (BitStream_buffer_output[12] == 1)? 5'd5:5'd6;				3 :NumCoeffTrailingOnes_len <= 5'd6;				4 :NumCoeffTrailingOnes_len <= 5'd7;				5 :NumCoeffTrailingOnes_len <= 5'd8;				6 :NumCoeffTrailingOnes_len <= 5'd9;				7 :NumCoeffTrailingOnes_len <= 5'd11;				8 :NumCoeffTrailingOnes_len <= 5'd12;				9 :NumCoeffTrailingOnes_len <= 5'd13;				10:NumCoeffTrailingOnes_len <= (BitStream_buffer_output[4] == 1)? 5'd13:5'd14;				11:NumCoeffTrailingOnes_len <= 5'd14;				12:NumCoeffTrailingOnes_len <= 5'd13;				default:NumCoeffTrailingOnes_len <= 5'd0;			endcase		else if (nC_n1)			case (heading_one_pos)				0:NumCoeffTrailingOnes_len <= 5'd1;				1:NumCoeffTrailingOnes_len <= 5'd2;				2:NumCoeffTrailingOnes_len <= 5'd3;				3:NumCoeffTrailingOnes_len <= 5'd6;				4:NumCoeffTrailingOnes_len <= 5'd6;				5:NumCoeffTrailingOnes_len <= 5'd7;				6:NumCoeffTrailingOnes_len <= 5'd8;				default:NumCoeffTrailingOnes_len <= 5'd7;			endcase		else if (nC_4to8)			case (heading_one_pos)				0 :NumCoeffTrailingOnes_len <= 5'd4;				1 :NumCoeffTrailingOnes_len <= 5'd5;				2 :NumCoeffTrailingOnes_len <= 5'd6;				3 :NumCoeffTrailingOnes_len <= 5'd7;				4 :NumCoeffTrailingOnes_len <= 5'd8;				5 :NumCoeffTrailingOnes_len <= 5'd9;				6 :NumCoeffTrailingOnes_len <= (BitStream_buffer_output[8:7] == 2'b11)? 5'd9:5'd10;				7 :NumCoeffTrailingOnes_len <= 5'd10;				8 :NumCoeffTrailingOnes_len <= 5'd10;				9 :NumCoeffTrailingOnes_len <= 5'd10;				10:NumCoeffTrailingOnes_len <= 5'd10;				default:NumCoeffTrailingOnes_len <= 5'd0;			endcase		else if (nC_GE8)					NumCoeffTrailingOnes_len <= 5'd6;		else			NumCoeffTrailingOnes_len <= 0;				//TrailingOnes	always @ (posedge clk)		if (reset_n == 0)			TrailingOnes_reg <= 0;		else if (cavlc_decoder_state == `NumCoeffTrailingOnes_LUT)			TrailingOnes_reg <= TrailingOnes;				always @ (nC_0to2 or nC_2to4 or nC_4to8 or nC_n1 or nC_GE8 	or nC_0to2_t0 or nC_0to2_t1 or nC_0to2_t2 or nC_0to2_t3  	or nC_2to4_t0 or nC_2to4_t1 or nC_2to4_t2 or nC_2to4_t3  	or nC_4to8_t0 or nC_4to8_t1 or nC_n1_t0  	or TrailingOnes_reg or heading_one_pos or BitStream_buffer_output)		if (nC_0to2)			begin				if (nC_0to2_t0) 					TrailingOnes <= heading_one_pos[1:0];				else if (nC_0to2_t1)					begin						if (heading_one_pos == 4'd3 && !BitStream_buffer_output[11])							TrailingOnes <= (BitStream_buffer_output[10])? 2'd0:2'd1;						else if (heading_one_pos == 4'd4 && BitStream_buffer_output[10:9] == 2'b01)							TrailingOnes <= 2'd2;						else							TrailingOnes <= 2'd3;					end				else if (nC_0to2_t2)					begin						if (heading_one_pos == 4'd5)							case (BitStream_buffer_output[9:8])								2'b00:TrailingOnes <= 2'd3;								2'b01:TrailingOnes <= 2'd2;								2'b10:TrailingOnes <= 2'd1;								2'b11:TrailingOnes <= 2'd0;							endcase						else if (heading_one_pos == 4'd6)							case (BitStream_buffer_output[8:7])								2'b00:TrailingOnes <= 2'd3;								2'b01:TrailingOnes <= 2'd2;								2'b10:TrailingOnes <= 2'd1;								2'b11:TrailingOnes <= 2'd0;							endcase						else if (heading_one_pos == 4'd7)							case (BitStream_buffer_output[7:6])								2'b00:TrailingOnes <= 2'd3;								2'b01:TrailingOnes <= 2'd2;								2'b10:TrailingOnes <= 2'd1;								2'b11:TrailingOnes <= 2'd0;							endcase						else 							case (BitStream_buffer_output[6:5])								2'b00:TrailingOnes <= 2'd3;								2'b01:TrailingOnes <= 2'd2;								2'b10:TrailingOnes <= 2'd1;								2'b11:TrailingOnes <= 2'd0;							endcase					end				else if (nC_0to2_t3)					begin 						if (heading_one_pos == 4'd9)							case (BitStream_buffer_output[4:3])								2'b00:TrailingOnes <= (BitStream_buffer_output[5])? 2'd3:2'd0;								2'b10:TrailingOnes <= 2'd1;								2'b01:TrailingOnes <= 2'd2;								2'b11:TrailingOnes <= 2'd0;							endcase						else							case (BitStream_buffer_output[3:2])								2'b00:TrailingOnes <= 2'd3;								2'b01:TrailingOnes <= 2'd2;								2'b10:TrailingOnes <= 2'd1;								2'b11:TrailingOnes <= 2'd0;							endcase					end				else					begin						if ((heading_one_pos == 4'd11 &&  BitStream_buffer_output[2:1] == 2'b11) ||                (heading_one_pos == 4'd12 &&  BitStream_buffer_output[1:0] == 2'b11) ||                (heading_one_pos == 4'd13 && (BitStream_buffer_output[1:0] == 2'b00  || BitStream_buffer_output[1:0] == 2'b11)))							TrailingOnes <= 2'd0;						else if ((heading_one_pos == 4'd11 && BitStream_buffer_output[2:1] == 2'b10) ||                     (heading_one_pos == 4'd12 && BitStream_buffer_output[1:0] == 2'b10) ||                     (heading_one_pos == 4'd13 && BitStream_buffer_output[1:0] == 2'b10) ||                      heading_one_pos == 4'd14)							TrailingOnes <= 2'd1;						else if ((heading_one_pos == 4'd11 && BitStream_buffer_output[2:1] == 2'b01) ||                     (heading_one_pos == 4'd12 && BitStream_buffer_output[1:0] == 2'b01) ||                     (heading_one_pos == 4'd13 && BitStream_buffer_output[1:0] == 2'b01))							TrailingOnes <= 2'd2;						else							TrailingOnes <= 2'd3;					end			end		else if (nC_2to4)			begin				if (nC_2to4_t0)					begin						if (heading_one_pos == 4'd0)							TrailingOnes <= {1'b0,~BitStream_buffer_output[14]};						else							TrailingOnes <= (BitStream_buffer_output[13])? 2'd2:2'd3;					end				else if (nC_2to4_t1)					begin						if ((heading_one_pos == 4'd2 && BitStream_buffer_output[12:10] == 3'b011) ||                (heading_one_pos == 4'd3 && BitStream_buffer_output[11:10] == 2'b11))							TrailingOnes <= 2'd0;						else if ((heading_one_pos == 4'd2 && (BitStream_buffer_output[12:11] == 2'b11 || BitStream_buffer_output[12:10] == 3'b010)) ||                     (heading_one_pos == 4'd3 &&  BitStream_buffer_output[11:10] == 2'b10))							TrailingOnes <= 2'd1;						else if ((heading_one_pos == 4'd2 && BitStream_buffer_output[12:10] == 3'b001) ||                     (heading_one_pos == 4'd3 && BitStream_buffer_output[11:10] == 2'b01))							TrailingOnes <= 2'd2;						else							TrailingOnes <= 2'd3;					end				else if (nC_2to4_t2)					begin						if (heading_one_pos == 4'd4)							case (BitStream_buffer_output[10:9])								2'b00:TrailingOnes <= 2'd3;								2'b01:TrailingOnes <= 2'd2;								2'b10:TrailingOnes <= 2'd1;								2'b11:TrailingOnes <= 2'd0;							endcase						else if (heading_one_pos == 4'd5)							case (BitStream_buffer_output[9:8])								2'b00:TrailingOnes <= 2'd0;								2'b01:TrailingOnes <= 2'd2;								2'b10:TrailingOnes <= 2'd1;								2'b11:TrailingOnes <= 2'd0;							endcase						else 							case (BitStream_buffer_output[8:7])								2'b00:TrailingOnes <= 2'd3;								2'b01:TrailingOnes <= 2'd2;								2'b10:TrailingOnes <= 2'd1;								2'b11:TrailingOnes <= 2'd0;							endcase					end				else if (nC_2to4_t3)					begin 						if ((heading_one_pos == 4'd7 && BitStream_buffer_output[6:5] == 2'b11) ||                 (heading_one_pos == 4'd8 && (BitStream_buffer_output[5:4] == 2'b11 || BitStream_buffer_output[6:4] == 3'b000)))							TrailingOnes <= 2'd0;						else if ((heading_one_pos == 4'd7 && BitStream_buffer_output[6:5] == 2'b10) ||                      (heading_one_pos == 4'd8 && BitStream_buffer_output[5:4] == 2'b10)) 							TrailingOnes <= 2'd1;						else if ((heading_one_pos == 4'd7 && BitStream_buffer_output[6:5] == 2'b01) ||                      (heading_one_pos == 4'd8 && BitStream_buffer_output[5:4] == 2'b01)) 							TrailingOnes <= 2'd2;						else							TrailingOnes <= 2'd3;					end				else					begin						if ((heading_one_pos == 4'd9  &&  BitStream_buffer_output[4:3] == 2'b11) ||                (heading_one_pos == 4'd10 && (BitStream_buffer_output[4:3] == 2'b11  || BitStream_buffer_output[4:2] == 3'b001)) ||                (heading_one_pos == 4'd11 &&  BitStream_buffer_output[3:2] == 2'b11))							TrailingOnes <= 2'd0;						else if ((heading_one_pos == 4'd9  &&  BitStream_buffer_output[4:3] == 2'b10) ||                     (heading_one_pos == 4'd10 && (BitStream_buffer_output[4:2] == 3'b000 || BitStream_buffer_output[4:2] == 3'b011)) ||                     (heading_one_pos == 4'd11 &&  BitStream_buffer_output[3:2] == 2'b10))							TrailingOnes <= 2'd1;						else if ((heading_one_pos == 4'd9  &&  BitStream_buffer_output[4:3] == 2'b01) ||                     (heading_one_pos == 4'd10 && (BitStream_buffer_output[4:3] == 2'b10  || BitStream_buffer_output[4:2] == 3'b010)) ||                     (heading_one_pos == 4'd11 &&  BitStream_buffer_output[3:2] == 2'b01))							TrailingOnes <= 2'd2;						else							TrailingOnes <= 2'd3;					end			end		else if (nC_n1)			begin 				if (nC_n1_t0)					begin 						if      (BitStream_buffer_output[15])	TrailingOnes <= 2'd1;						else if (BitStream_buffer_output[14])	TrailingOnes <= 2'd0;						else                                  TrailingOnes <= 2'd2;					end				else					begin						if ((heading_one_pos == 4'd3 && (BitStream_buffer_output[11:10] == 2'b00 || BitStream_buffer_output[11:10] == 2'b11)) ||                 heading_one_pos == 4'd4)							TrailingOnes <= 2'd0;						else if ((heading_one_pos == 4'd3 && BitStream_buffer_output[11:10] == 2'b10) ||                     (heading_one_pos == 4'd5 && BitStream_buffer_output[9]) ||                     (heading_one_pos == 4'd6 && BitStream_buffer_output[8]))							TrailingOnes <= 2'd1;						else if ((heading_one_pos == 4'd5 && !BitStream_buffer_output[9]) ||                     (heading_one_pos == 4'd6 && !BitStream_buffer_output[8]))							TrailingOnes <= 2'd2;						else							TrailingOnes <= 2'd3;					end			end		else if (nC_4to8)			begin				if (nC_4to8_t0)					begin						if      (BitStream_buffer_output[14:12] == 3'b111)	TrailingOnes <= 2'd0;						else if (BitStream_buffer_output[14:12] == 3'b110)	TrailingOnes <= 2'd1;						else if (BitStream_buffer_output[14:12] == 3'b101)	TrailingOnes <= 2'd2;						else                                                TrailingOnes <= 2'd3;					end				else if (nC_4to8_t1)					begin