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<defines>
`define CMD_AAA     #AUTOGEN_NEXT_CMD
`define CMD_AAS     #AUTOGEN_NEXT_CMD
`define CMD_DAA     #AUTOGEN_NEXT_CMD
`define CMD_DAS     #AUTOGEN_NEXT_CMD
</defines>

<decode>
dec_ready_one && decoder[7:0] == 8'h37
`CMD_AAA
SET(dec_is_8bit);
SET(consume_one);
</decode>

<decode>
dec_ready_one && decoder[7:0] == 8'h3F
`CMD_AAS
SET(dec_is_8bit);
SET(consume_one);
</decode>

<decode>
dec_ready_one && decoder[7:0] == 8'h27
`CMD_DAA
SET(dec_is_8bit);
SET(consume_one);
</decode>

<decode>
dec_ready_one && decoder[7:0] == 8'h2F
`CMD_DAS
SET(dec_is_8bit);
SET(consume_one);
</decode>

<read>
IF(rd_cmd == `CMD_AAA || rd_cmd == `CMD_AAS || rd_cmd == `CMD_DAA || rd_cmd == `CMD_DAS);
    
    SET(rd_dst_is_eax);
        
    SET(rd_req_eflags);
    SET(rd_req_eax);

    IF(rd_mutex_busy_eax); SET(rd_waiting); ENDIF();
ENDIF();
</read>

<execute_local>
wire e_bcd_condition_cf;

wire exe_bcd_condition_af;
wire exe_bcd_condition_cf;

wire [15:0] e_aaa_sum_ax;
wire [15:0] e_aaa_result;

wire [15:0] e_aas_sub_ax;
wire [15:0] e_aas_result;

wire [7:0]  e_daa_sum_low;
wire [7:0]  e_daa_step1;
wire [7:0]  e_daa_sum_high;
wire [7:0]  e_daa_result;

wire [7:0]  e_das_sub_low;
wire [7:0]  e_das_step1;
wire [7:0]  e_das_sub_high;
wire [7:0]  e_das_result;

//---------

assign e_bcd_condition_cf = (dst[7:0] > 8'h99 || cflag);

assign exe_bcd_condition_af = dst[3:0] > 4'd9 || aflag;
assign exe_bcd_condition_cf = e_bcd_condition_cf || (exe_bcd_condition_af && (cflag || (exe_cmd == `CMD_DAA)? dst[7:0] > 8'hF9 : dst[7:0] < 8'h06));

// AAA
assign e_aaa_sum_ax = dst[15:0] + 16'h0106;
assign e_aaa_result = (exe_bcd_condition_af)? { e_aaa_sum_ax[15:8], 4'b0, e_aaa_sum_ax[3:0] } : { dst[15:8], 4'd0, dst[3:0] };

// AAS
assign e_aas_sub_ax = dst[15:0] - 16'h0106;
assign e_aas_result = (exe_bcd_condition_af)? { e_aas_sub_ax[15:8], 4'b0, e_aas_sub_ax[3:0] } : { dst[15:8], 4'b0, dst[3:0] };

// DAA
assign e_daa_sum_low  = dst[7:0] + 8'h06;
assign e_daa_step1    = (exe_bcd_condition_af)? e_daa_sum_low : dst[7:0];
assign e_daa_sum_high = e_daa_step1 + 8'h60;
assign e_daa_result   = (e_bcd_condition_cf)? e_daa_sum_high : e_daa_step1;

// DAS
assign e_das_sub_low  = dst[7:0] - 8'h06;
assign e_das_step1    = (exe_bcd_condition_af)? e_das_sub_low : dst[7:0];
assign e_das_sub_high = e_das_step1 - 8'h60;
assign e_das_result   = (e_bcd_condition_cf)? e_das_sub_high : e_das_step1;
</execute_local>

<execute>
IF(exe_cmd == `CMD_AAA || exe_cmd == `CMD_AAS || exe_cmd == `CMD_DAA || exe_cmd == `CMD_DAS);
        
    SET(exe_result, (exe_cmd == `CMD_AAA)?  { 16'd0, e_aaa_result } :
                    (exe_cmd == `CMD_AAS)?  { 16'd0, e_aas_result } :
                    (exe_cmd == `CMD_DAA)?  { 16'd0, dst[15:8], e_daa_result } :
                                            { 16'd0, dst[15:8], e_das_result });
    
    SET(exe_result_signals, { 3'b0, exe_bcd_condition_af, exe_bcd_condition_cf });
    
    IF(exe_mutex_current[`MUTEX_EFLAGS_BIT]); SET(exe_waiting); ENDIF();
ENDIF();
</execute>

<write>
IF(wr_cmd == `CMD_AAA || wr_cmd == `CMD_AAS);
    SAVE(eax, { eax[31:16], result[15:0] });
    
    SAVE(zflag, zflag_result);
    SAVE(sflag, sflag_result);
    SAVE(pflag, pflag_result);

    SAVE(aflag, result_signals[1]);
    SAVE(cflag, result_signals[1]);
    SAVE(oflag, oflag_arith);
ENDIF();
</write>

<write>
IF(wr_cmd == `CMD_DAA || wr_cmd == `CMD_DAS);
    SAVE(eax, { eax[31:16], result[15:0] });
    
    SAVE(zflag, zflag_result);
    SAVE(sflag, sflag_result);
    SAVE(pflag, pflag_result);

    SAVE(aflag, result_signals[1]);
    SAVE(cflag, result_signals[0]);
    SAVE(oflag, oflag_arith);
ENDIF();
</write>