src/parser.vhd

   1 library ieee;
   2 use ieee.std_logic_1164.all;
   3 use ieee.numeric_std.all;
   4 use work.gen_pkg.all;
   5
   6 entity parser is
   7         port (
   8                 sys_clk : in std_logic;
   9                 sys_res_n : in std_logic;
  10                 -- History
  11                 p_rget : out std_logic;
  12                 p_rdone : in std_logic;
  13                 p_read : in hbyte;
  14                 p_wtake : out std_logic;
  15                 p_wdone : in std_logic;
  16                 p_write : out hbyte;
  17                 p_finished : out std_logic;
  18                 -- Scanner
  19                 do_it : in std_logic;
  20                 finished : out std_logic
  21         );
  22 end entity parser;
  23
  24 architecture beh of parser is
  25         type PARSER_STATE is (SIDLE, SREAD_NEWNUMBER, SREAD_SPACE_GET,
  26                 SREAD_SPACE_GET_SIGN, SREAD_SPACE_PROC, SREAD_SPACE_PROC_SIGN, SREAD_OP1, SREAD_OP2,
  27                 SREAD_SIGN, SREAD_NEXTBYTE, SREAD_CALCNUMBER1, SREAD_CALCNUMBER2, SCALC_1,
  28                 SCALC_14, SCALC_15, SCALC_2, SWRITE_CHAR0, SWRITE_CHAR1, SWRITE_CHAR2,
  29                 SWRITE_SIGN1, SWRITE_SIGN2, SDONE, SERROR1, SERROR2);
  30         signal state_int, state_next : PARSER_STATE;
  31         signal z_int, z_next, strich_int, strich_next, wtmp_int, wtmp_next : csigned;
  32         signal punkt_int, punkt_next : csigned;
  33         signal rbyte_int, rbyte_next : hbyte;
  34         signal p_write_int, p_write_next : hbyte;
  35         signal p_rget_int, p_rget_next : std_logic;
  36         signal p_wtake_int, p_wtake_next : std_logic;
  37         signal p_finished_int, p_finished_next : std_logic;
  38         signal finished_int, finished_next : std_logic;
  39         signal aktop_int, aktop_next : alu_ops;
  40         signal opp_int, opp_next : alu_ops;
  41         signal opcode_int, opcode_next : alu_ops;
  42         signal op1_int, op1_next : csigned;
  43         signal op2_int, op2_next : csigned;
  44         signal do_calc_int, do_calc_next : std_logic;
  45         signal z_sign_next, z_sign_int : std_logic;
  46         signal firstz_next, firstz_int : boolean;
  47         signal err_next, err_int : hstr_int;
  48         signal errc_next, errc_int : hstr_int;
  49         signal errc_tmp_next, errc_tmp_int : hstr_int;
  50         -- ALU
  51         signal opcode : alu_ops;
  52         signal op1 : csigned;
  53         signal op2 : csigned;
  54         signal op3 : csigned;
  55         signal opM : csigned;
  56         signal do_calc : std_logic;
  57         signal calc_done : std_logic;
  58         signal calc_error : std_logic;
  59 begin
  60         instalu : entity work.alu(beh)
  61         port map
  62         (
  63                 sys_clk => sys_clk,
  64                 sys_res_n => sys_res_n,
  65                 do_calc => do_calc,
  66                 calc_done => calc_done,
  67                 calc_error => calc_error,
  68                 op1 => op1,
  69                 op2 => op2,
  70                 op3 => op3,
  71                 opM => opM,
  72                 opcode => opcode
  73         );
  74
  75         p_write <= p_write_int;
  76         p_rget <= p_rget_int;
  77         p_wtake <= p_wtake_int;
  78         p_finished <= p_finished_int;
  79         finished <= finished_int;
  80
  81         opcode <= opcode_int;
  82         op1 <= op1_int;
  83         op2 <= op2_int;
  84         do_calc <= do_calc_int;
  85
  86         process(sys_clk, sys_res_n)
  87         begin
  88                 if sys_res_n = '0' then
  89                         state_int <= SIDLE;
  90                         z_int <= (others => '0');
  91                         z_sign_int <= '0';
  92                         strich_int <= (others => '0');
  93                         punkt_int <= (others => '0');
  94                         wtmp_int <= (others => '0');
  95                         rbyte_int <= (others => '0');
  96                         aktop_int <= ALU_NOP;
  97                         opp_int <= ALU_NOP;
  98                         err_int <= 0;
  99                         errc_int <= 71;
 100                         errc_tmp_int <= 0;
 101                         firstz_int <= true;
 102                         -- out ports
 103                         p_rget_int <= '0';
 104                         p_write_int <= (others => '0');
 105                         p_wtake_int <= '0';
 106                         p_finished_int <= '0';
 107                         finished_int <= '0';
 108                         opcode_int <= ALU_NOP;
 109                         op1_int <= (others => '0');
 110                         op2_int <= (others => '0');
 111                         do_calc_int <= '0';
 112                 elsif rising_edge(sys_clk) then
 113                         -- internal
 114                         state_int <= state_next;
 115                         z_int <= z_next;
 116                         z_sign_int <= z_sign_next;
 117                         strich_int <= strich_next;
 118                         punkt_int <= punkt_next;
 119                         wtmp_int <= wtmp_next;
 120                         rbyte_int <= rbyte_next;
 121                         aktop_int <= aktop_next;
 122                         opp_int <= opp_next;
 123                         err_int <= err_next;
 124                         errc_int <= errc_next;
 125                         errc_tmp_int <= errc_tmp_next;
 126                         firstz_int <= firstz_next;
 127                         -- out ports
 128                         p_rget_int <= p_rget_next;
 129                         p_write_int <= p_write_next;
 130                         p_wtake_int <= p_wtake_next;
 131                         p_finished_int <= p_finished_next;
 132                         finished_int <= finished_next;
 133                         opcode_int <= opcode_next;
 134                         op1_int <= op1_next;
 135                         op2_int <= op2_next;
 136                         do_calc_int <= do_calc_next;
 137                 end if;
 138         end process;
 139
 140         -- next state
 141         process(do_it, p_rdone, p_wdone, p_read, aktop_int, strich_int, punkt_int,
 142                         calc_done, wtmp_int, opp_int, z_sign_int, err_int, errc_int,
 143                         calc_error, op2_int, state_int, p_write_int, z_int, rbyte_int,
 144                         p_rget_int, opcode_int, op1_int, op3, opM, do_calc_int,
 145                         errc_tmp_int, firstz_int)
 146                 function hbyte2csigned (x : hbyte) return csigned is
 147                         variable y : csigned;
 148                 begin
 149                         case x is
 150                                 when x"30" => y := x"00000000";
 151                                 when x"31" => y := x"00000001";
 152                                 when x"32" => y := x"00000002";
 153                                 when x"33" => y := x"00000003";
 154                                 when x"34" => y := x"00000004";
 155                                 when x"35" => y := x"00000005";
 156                                 when x"36" => y := x"00000006";
 157                                 when x"37" => y := x"00000007";
 158                                 when x"38" => y := x"00000008";
 159                                 when x"39" => y := x"00000009";
 160                                 when others => assert(false) report "hbyte2csigned: shouldn't happen";
 161                         end case;
 162                         return y;
 163                 end function hbyte2csigned;
 164
 165                 function csigned2hbyte (x : csigned) return hbyte is
 166                         variable y : hbyte;
 167                 begin
 168                         case x is
 169                                 when x"00000000" => y := x"30";
 170                                 when x"00000001" => y := x"31";
 171                                 when x"00000002" => y := x"32";
 172                                 when x"00000003" => y := x"33";
 173                                 when x"00000004" => y := x"34";
 174                                 when x"00000005" => y := x"35";
 175                                 when x"00000006" => y := x"36";
 176                                 when x"00000007" => y := x"37";
 177                                 when x"00000008" => y := x"38";
 178                                 when x"00000009" => y := x"39";
 179                                 when others => assert(false) report "csigned2hbyte: shouldn't happen";
 180                         end case;
 181                         return y;
 182                 end function csigned2hbyte;
 183
 184                 variable multmp : signed(((2*CBITS)-1) downto 0);
 185                 variable tmp : csigned;
 186
 187                 type errstrings is array (natural range 1 to 3) of hstring;
 188                 constant error_str : errstrings := (
 189                         1 => " Fehler:                             Division durch Null               " & nul,
 190                         2 => " Fehler:                             Syntax                            " & nul,
 191                         3 => " Fehler:                             Over- bzw. Underflow              " & nul
 192                 );
 193         begin
 194                 state_next <= state_int;
 195                 -- internal
 196                 z_next <= z_int;
 197                 z_sign_next <= z_sign_int;
 198                 strich_next <= strich_int;
 199                 punkt_next <= punkt_int;
 200                 wtmp_next <= wtmp_int;
 201                 rbyte_next <= rbyte_int;
 202                 aktop_next <= aktop_int;
 203                 opp_next <= opp_int;
 204                 err_next <= err_int;
 205                 errc_next <= errc_int;
 206                 errc_tmp_next <= errc_tmp_int;
 207                 firstz_next <= firstz_int;
 208                 -- signals
 209                 p_rget_next <= '0';
 210                 p_write_next <= p_write_int;
 211                 p_wtake_next <= '0';
 212                 p_finished_next <= '0';
 213                 finished_next <= '0';
 214                 opcode_next <= opcode_int;
 215                 op1_next <= op1_int;
 216                 op2_next <= op2_int;
 217                 do_calc_next <= '0';
 218
 219                 case state_int is
 220                         when SIDLE =>
 221                                 strich_next <= (others => '0');
 222                                 punkt_next <= (0 => '1', others => '0');
 223                                 opp_next <= ALU_NOP;
 224                                 if do_it = '1' then
 225                                         state_next <= SREAD_NEWNUMBER;
 226                                 end if;
 227
 228                         when SREAD_NEWNUMBER =>
 229                                 z_next <= (others => '0');
 230                                 z_sign_next <= '0';
 231                                 firstz_next <= true;
 232                                 rbyte_next <= (others => '0');
 233                                 p_write_next <= (others => '0');
 234                                 aktop_next <= ALU_NOP;
 235                                 state_next <= SREAD_SPACE_GET;
 236
 237                         when SREAD_SPACE_GET =>
 238                                 p_rget_next <= '1';
 239                                 if p_rdone = '1' then
 240                                         state_next <= SREAD_SPACE_PROC;
 241                                 end if;
 242                         when SREAD_SPACE_GET_SIGN =>
 243                                 p_rget_next <= '1';
 244                                 if p_rdone = '1' then
 245                                         state_next <= SREAD_SPACE_PROC_SIGN;
 246                                 end if;
 247                         when SREAD_SPACE_PROC | SREAD_SPACE_PROC_SIGN =>
 248                                 case p_read is
 249                                         when x"20" => null;
 250                                         when x"2D" =>
 251                                                 case state_int is
 252                                                         when SREAD_SPACE_PROC =>
 253                                                                 case state_int is
 254                                                                         when SREAD_SPACE_PROC => state_next <= SREAD_SIGN;
 255                                                                         when others => assert(false) report "wtf @ state3";
 256                                                                 end case;
 257
 258                                                         when SREAD_SPACE_PROC_SIGN =>
 259                                                                 p_rget_next <= '1';
 260                                                                 case state_int is
 261                                                                         when SREAD_SPACE_PROC => state_next <= SREAD_NEXTBYTE;
 262                                                                         when SREAD_SPACE_PROC_SIGN => state_next <= SREAD_OP1;
 263                                                                         when others => assert(false) report "wtf @ state2";
 264                                                                 end case;
 265
 266                                                         when others => assert(false) report "SREAD_SPACE_PROC/3: shouldn't happen";
 267                                                 end case;
 268                                         when others =>
 269                                                 p_rget_next <= '1';
 270                                                 case state_int is
 271                                                         when SREAD_SPACE_PROC => state_next <= SREAD_NEXTBYTE;
 272                                                         when SREAD_SPACE_PROC_SIGN => state_next <= SREAD_OP1;
 273                                                         when others => assert(false) report "wtf @ state2";
 274                                                 end case;
 275                                 end case;
 276
 277                                 if p_rdone = '0' then
 278                                         case state_int is
 279                                                 when SREAD_SPACE_PROC => state_next <= SREAD_SPACE_GET;
 280                                                 when SREAD_SPACE_PROC_SIGN => state_next <= SREAD_SPACE_GET_SIGN;
 281                                                 when others => assert(false) report "wtf @ state1";
 282                                         end case;
 283                                 end if;
 284                         when SREAD_SIGN =>
 285                                 z_sign_next <= '1';
 286                                 if p_rdone = '0' then
 287                                         state_next <= SREAD_NEXTBYTE;
 288                                 end if;
 289                         when SREAD_NEXTBYTE =>
 290                                 p_rget_next <= '1';
 291                                 if p_rdone = '1' then
 292                                         state_next <= SREAD_CALCNUMBER1;
 293                                 end if;
 294                         when SREAD_CALCNUMBER1 =>
 295                                 case p_read is
 296                                         -- '+', '-', '*', '/'
 297                                         when x"2B" | x"2D" | x"2A" | x"2F" | x"00" =>
 298                                                 if firstz_int then
 299                                                         err_next <= 2;
 300                                                 else
 301                                                         state_next <= SREAD_OP1;
 302                                                         p_rget_next <= '1';
 303                                                 end if;
 304
 305                                         -- ' '
 306                                         when x"20" =>
 307                                                 state_next <= SREAD_SPACE_PROC_SIGN;
 308                                                 p_rget_next <= '1';
 309
 310                                         when others =>
 311                                                 op1_next <= z_int;
 312                                                 opcode_next <= ALU_MUL;
 313                                                 op2_next <= to_signed(10,CBITS);
 314                                                 firstz_next <= false;
 315                                                 do_calc_next <= '1';
 316                                 end case;
 317                                 if calc_done = '1' then
 318                                         state_next <= SREAD_CALCNUMBER2;
 319                                 end if;
 320                         when SREAD_CALCNUMBER2 =>
 321                                 z_next <= op3 + hbyte2csigned(p_read);
 322                                 if p_rdone = '0' and calc_done = '0' then
 323                                         state_next <= SREAD_NEXTBYTE;
 324                                 end if;
 325
 326                         when SREAD_OP1 =>
 327                                 case p_read is
 328                                         when x"2B" => aktop_next <= ALU_ADD; -- '+'
 329                                         when x"2D" => aktop_next <= ALU_SUB; -- '-'
 330                                         when x"2A" => aktop_next <= ALU_MUL; -- '*'
 331                                         when x"2F" => aktop_next <= ALU_DIV; -- '/'
 332                                         when x"00" => aktop_next <= ALU_DONE; -- '\0'
 333
 334                                         when others => err_next <= 2;
 335                                 end case;
 336                                 state_next <= SREAD_OP2;
 337                         when SREAD_OP2 =>
 338                                 if p_rdone = '0' then
 339                                         if aktop_int /= ALU_NOP then
 340                                                 state_next <= SCALC_1;
 341                                         end if;
 342                                 end if;
 343
 344                         when SCALC_1 =>
 345                                 if z_sign_int = '1' then
 346                                         tmp := (not z_int) + 1;
 347                                         z_next <= tmp;
 348                                         z_sign_next <= '0';
 349                                 else
 350                                         tmp := z_int;
 351                                 end if;
 352
 353                                 case opp_int is
 354                                         when ALU_NOP | ALU_ADD | ALU_SUB =>
 355                                                 case opp_int  is
 356                                                         when ALU_SUB =>
 357                                                                 -- xst (xilinx) workaround
 358                                                                 if x"80000000" = tmp then
 359                                                                         -- vgl. testfall 37 und 38
 360                                                                         err_next <= 3;
 361                                                                         op1_next <= tmp;
 362                                                                 else
 363                                                                         op1_next <= (not tmp) + 1;
 364                                                                 end if;
 365                                                         when others => op1_next <= tmp;
 366                                                 end case;
 367                                                 case aktop_int is
 368                                                         when ALU_ADD | ALU_SUB | ALU_DONE =>
 369                                                                 opcode_next <= ALU_ADD;
 370                                                                 op2_next <= strich_int;
 371                                                         when ALU_MUL | ALU_DIV =>
 372                                                                 opcode_next <= ALU_MUL;
 373                                                                 op2_next <= punkt_int;
 374                                                         when others => assert(false) report "SCALC_1/1: shouldn't happen!";
 375                                                 end case;
 376
 377                                         when ALU_MUL | ALU_DIV =>
 378                                                 case aktop_int is
 379                                                         when ALU_ADD | ALU_SUB | ALU_DONE | ALU_MUL | ALU_DIV =>
 380                                                                 op1_next <= punkt_int;
 381                                                                 opcode_next <= opp_int;
 382                                                                 op2_next <= tmp;
 383                                                         when others => assert(false) report "SCALC_1/2: shouldn't happen!";
 384                                                 end case;
 385                                         when others => assert(false) report "SCALC_1/3: shouldn't happen!";
 386                                 end case;
 387                                 do_calc_next <= '1';
 388
 389                                 if calc_done = '1' then
 390                                         case opp_int is
 391                                                 -- spezialfall: eine zwischenberechnung wird fuer diese
 392                                                 -- kombination benoetigt
 393                                                 when ALU_MUL | ALU_DIV =>
 394                                                         case aktop_int is
 395                                                                 when ALU_ADD | ALU_SUB | ALU_DONE => state_next <= SCALC_14;
 396                                                                 when others => state_next <= SCALC_2;
 397                                                         end case;
 398                                                 when others => state_next <= SCALC_2;
 399                                         end case;
 400                                 end if;
 401                         when SCALC_14 =>
 402                                 -- ueberpruefung kann man sich sparen, da diese ohnehin in
 403                                 -- nextstate gemacht wird.
 404                                 op1_next <= op3;
 405                                 do_calc_next <= '0';
 406
 407                                 if calc_done = '0' then
 408                                         state_next <= SCALC_15;
 409                                 end if;
 410                         when SCALC_15 =>
 411                                 -- ueberpruefung kann man sich sparen, da diese ohnehin in
 412                                 -- nextstate gemacht wird.
 413                                 opcode_next <= ALU_ADD;
 414                                 op2_next <= strich_int;
 415                                 punkt_next <= (0 => '1', others => '0');
 416                                 do_calc_next <= '1';
 417
 418                                 if calc_done = '1' then
 419                                         state_next <= SCALC_2;
 420                                 end if;
 421                         when SCALC_2 =>
 422                                 case opp_int is
 423                                         when ALU_NOP | ALU_ADD | ALU_SUB | ALU_MUL | ALU_DIV =>
 424                                                 case aktop_int is
 425                                                         when ALU_ADD | ALU_SUB | ALU_DONE =>
 426                                                                 if aktop_int = ALU_DONE and op3 < 0 then
 427                                                                         strich_next <= (not op3) + 1;
 428                                                                         wtmp_next <= (not op3) + 1;
 429                                                                         z_sign_next <= '1';
 430                                                                 else
 431                                                                         strich_next <= op3;
 432                                                                         wtmp_next <= op3;
 433                                                                 end if;
 434                                                         when ALU_MUL | ALU_DIV =>
 435                                                                 punkt_next <= op3;
 436                                                         when others => assert (false) report "SCALC_2/1: shouldn't happen!";
 437                                                 end case;
 438                                         when ALU_DONE => null;
 439                                         when others => assert (false) report "SCALC_2/2: shouldn't happen!";
 440                                 end case;
 441                                 -- aktuelle rechenoperation fuer naechste 'runde' uebernehmen
 442                                 opp_next <= aktop_int;
 443
 444                                 if calc_done = '0' then
 445                                         if aktop_int = ALU_DONE then
 446                                                 state_next <= SWRITE_CHAR2;
 447                                         else
 448                                                 state_next <= SREAD_NEWNUMBER;
 449                                         end if;
 450                                 end if;
 451
 452                         when SWRITE_CHAR0 =>
 453                                 -- fuer testfall 39 und 40
 454                                 if strich_int = to_signed(-214748364,CBITS) then
 455                                         op1_next <= to_signed(214748364,CBITS);
 456                                         strich_next <= to_signed(214748364,CBITS);
 457                                 else
 458                                         op1_next <= strich_int;
 459                                 end if;
 460                                 opcode_next <= ALU_DIV;
 461                                 op2_next <= to_signed(10,CBITS);
 462                                 do_calc_next <= '1';
 463
 464                                 if calc_done = '1' then
 465                                         state_next <= SWRITE_CHAR1;
 466                                 end if;
 467                         when SWRITE_CHAR1 =>
 468                                 do_calc_next <= '1';
 469                                 p_wtake_next <= '1';
 470                                 tmp := opM;
 471                                 p_write_next <= csigned2hbyte(tmp);
 472                                 wtmp_next <= op3;
 473
 474                                 if p_wdone = '1' then
 475                                         -- ueberpruefung auf -2147483648 fuer testfall 39 und 40
 476                                         -- x"80000000": xst (xilinx) workaround
 477                                         if strich_int < 10 and strich_int /= x"80000000" then
 478                                                 if z_sign_int = '1' then
 479                                                         state_next <= SWRITE_SIGN1;
 480                                                 else
 481                                                         state_next <= SDONE;
 482                                                 end if;
 483                                         else
 484                                                 state_next <= SWRITE_CHAR2;
 485                                         end if;
 486                                 end if;
 487                         when SWRITE_CHAR2 =>
 488                                 strich_next <= wtmp_int;
 489                                 if p_wdone = '0' and calc_done = '0' then
 490                                         state_next <= SWRITE_CHAR0;
 491                                 end if;
 492
 493                         when SWRITE_SIGN1 =>
 494                                 if p_wdone = '0' then
 495                                         state_next <= SWRITE_SIGN2;
 496                                 end if;
 497                         when SWRITE_SIGN2 =>
 498                                 if z_sign_int = '1' then
 499                                         p_wtake_next <= '1';
 500                                         p_write_next <= x"2D";
 501                                 else
 502                                         assert(false) report "SWRITE_SIGN: shouldn't happen!";
 503                                 end if;
 504
 505                                 if p_wdone = '1' then
 506                                         state_next <= SDONE;
 507                                 end if;
 508
 509                         when SERROR1 =>
 510                                 if p_wdone = '1' then
 511                                         if errc_int <= 2 then
 512                                                 state_next <= SDONE;
 513                                         else
 514                                                 state_next <= SERROR2;
 515                                         end if;
 516                                 end if;
 517                         when SERROR2 =>
 518                                 if p_wdone = '0' then
 519                                         state_next <= SERROR1;
 520                                 end if;
 521
 522                         when SDONE =>
 523                                 err_next <= 0;
 524                                 errc_next <= 71;
 525                                 p_finished_next <= '1';
 526                                 finished_next <= '1';
 527
 528                                 if p_wdone = '0' and do_it = '0' then
 529                                         state_next <= SIDLE;
 530                                 end if;
 531                 end case;
 532
 533                 -- fehlerbehandlung
 534                 case state_int is
 535                         when SERROR1 =>
 536                                 p_wtake_next <= '1';
 537                                 p_write_next <= hbyte(to_unsigned (character'pos(error_str(err_int)(errc_int)),8));
 538                                 errc_tmp_next <= errc_int - 1;
 539                         when SERROR2 =>
 540                                 errc_next <= errc_tmp_int;
 541                         when SDONE => null;
 542                         when others =>
 543                                 if calc_error = '1' then
 544                                         if op2_int = 0 then
 545                                                 err_next <= 1;
 546                                         else
 547                                                 err_next <= 3;
 548                                         end if;
 549                                 end if;
 550
 551                                 if err_int > 0 then
 552                                         state_next <= SERROR1;
 553                                 end if;
 554                 end case;
 555         end process;
 556 end architecture beh;