gcc/jit/docs/examples/tut04-toyvm/toyvm.cc

   1 /* A simple stack-based virtual machine to demonstrate
   2    JIT-compilation.
   3    Copyright (C) 2014-2016 Free Software Foundation, Inc.
   4
   5 This file is part of GCC.
   6
   7 GCC is free software; you can redistribute it and/or modify it
   8 under the terms of the GNU General Public License as published by
   9 the Free Software Foundation; either version 3, or (at your option)
  10 any later version.
  11
  12 GCC is distributed in the hope that it will be useful, but
  13 WITHOUT ANY WARRANTY; without even the implied warranty of
  14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15 General Public License for more details.
  16
  17 You should have received a copy of the GNU General Public License
  18 along with GCC; see the file COPYING3.  If not see
  19 <http://www.gnu.org/licenses/>.  */
  20
  21 #include <assert.h>
  22 #include <errno.h>
  23 #include <stdio.h>
  24 #include <stdlib.h>
  25 #include <string.h>
  26
  27 #include <dejagnu.h>
  28
  29 #include <libgccjit++.h>
  30
  31 /* Functions are compiled to this function ptr type.  */
  32 typedef int (*toyvm_compiled_func) (int);
  33
  34 enum opcode {
  35   /* Ops taking no operand.  */
  36   DUP,
  37   ROT,
  38   BINARY_ADD,
  39   BINARY_SUBTRACT,
  40   BINARY_MULT,
  41   BINARY_COMPARE_LT,
  42   RECURSE,
  43   RETURN,
  44
  45   /* Ops taking an operand.  */
  46   PUSH_CONST,
  47   JUMP_ABS_IF_TRUE
  48 };
  49
  50 #define FIRST_UNARY_OPCODE (PUSH_CONST)
  51
  52 const char * const opcode_names[] = {
  53   "DUP",
  54   "ROT",
  55   "BINARY_ADD",
  56   "BINARY_SUBTRACT",
  57   "BINARY_MULT",
  58   "BINARY_COMPARE_LT",
  59   "RECURSE",
  60   "RETURN",
  61
  62   "PUSH_CONST",
  63   "JUMP_ABS_IF_TRUE",
  64 };
  65
  66 struct toyvm_op
  67 {
  68   /* Which operation.  */
  69   enum opcode op_opcode;
  70
  71   /* Some opcodes take an argument.  */
  72   int op_operand;
  73
  74   /* The line number of the operation within the source file.  */
  75   int op_linenum;
  76 };
  77
  78 #define MAX_OPS  (64)
  79
  80 class toyvm_function
  81 {
  82 public:
  83   void
  84   add_op (enum opcode opcode,
  85           int operand, int linenum);
  86
  87   void
  88   add_unary_op (enum opcode opcode,
  89                 const char *rest_of_line, int linenum);
  90
  91   static toyvm_function *
  92   parse (const char *filename, const char *name);
  93
  94   void
  95   disassemble_op (toyvm_op *op, int index, FILE *out);
  96
  97   void
  98   disassemble (FILE *out);
  99
 100   int
 101   interpret (int arg, FILE *trace);
 102
 103   toyvm_compiled_func
 104   compile ();
 105
 106 private:
 107   const char *fn_filename;
 108   int         fn_num_ops;
 109   toyvm_op    fn_ops[MAX_OPS];
 110   friend struct compilation_state;
 111 };
 112
 113 #define MAX_STACK_DEPTH (8)
 114
 115 class toyvm_frame
 116 {
 117 public:
 118   void push (int arg);
 119   int pop ();
 120   void dump_stack (FILE *out);
 121
 122 private:
 123   toyvm_function *frm_function;
 124   int             frm_pc;
 125   int             frm_stack[MAX_STACK_DEPTH];
 126   int             frm_cur_depth;
 127
 128   friend int toyvm_function::interpret (int arg, FILE *trace);
 129
 130 };
 131
 132 void
 133 toyvm_function::add_op (enum opcode opcode,
 134                         int operand, int linenum)
 135 {
 136   toyvm_op *op;
 137   assert (fn_num_ops < MAX_OPS);
 138   op = &fn_ops[fn_num_ops++];
 139   op->op_opcode = opcode;
 140   op->op_operand = operand;
 141   op->op_linenum = linenum;
 142 }
 143
 144 void
 145 toyvm_function::add_unary_op (enum opcode opcode,
 146                               const char *rest_of_line, int linenum)
 147 {
 148   int operand = atoi (rest_of_line);
 149   add_op (opcode, operand, linenum);
 150 }
 151
 152 static char *
 153 get_function_name (const char *filename)
 154 {
 155   /* Skip any path separators.  */
 156   const char *pathsep = strrchr (filename, '/');
 157   if (pathsep)
 158     filename = pathsep + 1;
 159
 160   /* Copy filename to funcname.  */
 161   char *funcname = (char *)malloc (strlen (filename) + 1);
 162
 163   strcpy (funcname, filename);
 164
 165   /* Convert "." to NIL terminator.  */
 166   *(strchr (funcname, '.')) = '\0';
 167
 168   return funcname;
 169 }
 170
 171 toyvm_function *
 172 toyvm_function::parse (const char *filename, const char *name)
 173 {
 174   FILE *f = NULL;
 175   toyvm_function *fn = NULL;
 176   char *line = NULL;
 177   ssize_t linelen;
 178   size_t bufsize;
 179   int linenum = 0;
 180
 181   assert (filename);
 182   assert (name);
 183
 184   f = fopen (filename, "r");
 185   if (!f)
 186     {
 187       fprintf (stderr,
 188                "cannot open file %s: %s\n",
 189                filename, strerror (errno));
 190       goto error;
 191     }
 192
 193   fn = (toyvm_function *)calloc (1, sizeof (toyvm_function));
 194   if (!fn)
 195     {
 196       fprintf (stderr, "out of memory allocating toyvm_function\n");
 197       goto error;
 198     }
 199   fn->fn_filename = filename;
 200
 201   /* Read the lines of the file.  */
 202   while ((linelen = getline (&line, &bufsize, f)) != -1)
 203     {
 204       /* Note that this is a terrible parser, but it avoids the need to
 205          bring in lex/yacc as a dependency.  */
 206       linenum++;
 207
 208       if (0)
 209         fprintf (stdout, "%3d: %s", linenum, line);
 210
 211       /* Lines beginning with # are comments.  */
 212       if (line[0] == '#')
 213         continue;
 214
 215       /* Skip blank lines.  */
 216       if (line[0] == '\n')
 217         continue;
 218
 219 #define LINE_MATCHES(OPCODE) (0 == strncmp ((OPCODE), line, strlen (OPCODE)))
 220       if (LINE_MATCHES ("DUP\n"))
 221         fn->add_op (DUP, 0, linenum);
 222       else if (LINE_MATCHES ("ROT\n"))
 223         fn->add_op (ROT, 0, linenum);
 224       else if (LINE_MATCHES ("BINARY_ADD\n"))
 225         fn->add_op (BINARY_ADD, 0, linenum);
 226       else if (LINE_MATCHES ("BINARY_SUBTRACT\n"))
 227         fn->add_op (BINARY_SUBTRACT, 0, linenum);
 228       else if (LINE_MATCHES ("BINARY_MULT\n"))
 229         fn->add_op (BINARY_MULT, 0, linenum);
 230       else if (LINE_MATCHES ("BINARY_COMPARE_LT\n"))
 231         fn->add_op (BINARY_COMPARE_LT, 0, linenum);
 232       else if (LINE_MATCHES ("RECURSE\n"))
 233         fn->add_op (RECURSE, 0, linenum);
 234       else if (LINE_MATCHES ("RETURN\n"))
 235         fn->add_op (RETURN, 0, linenum);
 236       else if (LINE_MATCHES ("PUSH_CONST "))
 237         fn->add_unary_op (PUSH_CONST,
 238                           line + strlen ("PUSH_CONST "), linenum);
 239       else if (LINE_MATCHES ("JUMP_ABS_IF_TRUE "))
 240         fn->add_unary_op (JUMP_ABS_IF_TRUE,
 241                           line + strlen("JUMP_ABS_IF_TRUE "), linenum);
 242       else
 243         {
 244           fprintf (stderr, "%s:%d: parse error\n", filename, linenum);
 245           free (fn);
 246           fn = NULL;
 247           goto error;
 248         }
 249 #undef LINE_MATCHES
 250     }
 251   free (line);
 252   fclose (f);
 253
 254   return fn;
 255
 256  error:
 257   free (line);
 258   if (f)
 259     fclose (f);
 260   free (fn);
 261   return NULL;
 262 }
 263
 264 void
 265 toyvm_function::disassemble_op (toyvm_op *op, int index, FILE *out)
 266 {
 267   fprintf (out, "%s:%d: index %d: %s",
 268            fn_filename, op->op_linenum, index,
 269            opcode_names[op->op_opcode]);
 270   if (op->op_opcode >= FIRST_UNARY_OPCODE)
 271     fprintf (out, " %d", op->op_operand);
 272   fprintf (out, "\n");
 273 }
 274
 275 void
 276 toyvm_function::disassemble (FILE *out)
 277 {
 278   int i;
 279   for (i = 0; i < fn_num_ops; i++)
 280     {
 281       toyvm_op *op = &fn_ops[i];
 282       disassemble_op (op, i, out);
 283     }
 284 }
 285
 286 void
 287 toyvm_frame::push (int arg)
 288 {
 289   assert (frm_cur_depth < MAX_STACK_DEPTH);
 290   frm_stack[frm_cur_depth++] = arg;
 291 }
 292
 293 int
 294 toyvm_frame::pop ()
 295 {
 296   assert (frm_cur_depth > 0);
 297   return frm_stack[--frm_cur_depth];
 298 }
 299
 300 void
 301 toyvm_frame::dump_stack (FILE *out)
 302 {
 303   int i;
 304   fprintf (out, "stack:");
 305   for (i = 0; i < frm_cur_depth; i++)
 306     {
 307       fprintf (out, " %d", frm_stack[i]);
 308     }
 309   fprintf (out, "\n");
 310 }
 311
 312 /* Execute the given function.  */
 313
 314 int
 315 toyvm_function::interpret (int arg, FILE *trace)
 316 {
 317   toyvm_frame frame;
 318 #define PUSH(ARG) (frame.push (ARG))
 319 #define POP(ARG) (frame.pop ())
 320
 321   frame.frm_function = this;
 322   frame.frm_pc = 0;
 323   frame.frm_cur_depth = 0;
 324
 325   PUSH (arg);
 326
 327   while (1)
 328     {
 329       toyvm_op *op;
 330       int x, y;
 331       assert (frame.frm_pc < fn_num_ops);
 332       op = &fn_ops[frame.frm_pc++];
 333
 334       if (trace)
 335         {
 336           frame.dump_stack (trace);
 337           disassemble_op (op, frame.frm_pc, trace);
 338         }
 339
 340       switch (op->op_opcode)
 341         {
 342           /* Ops taking no operand.  */
 343         case DUP:
 344           x = POP ();
 345           PUSH (x);
 346           PUSH (x);
 347           break;
 348
 349         case ROT:
 350           y = POP ();
 351           x = POP ();
 352           PUSH (y);
 353           PUSH (x);
 354           break;
 355
 356         case BINARY_ADD:
 357           y = POP ();
 358           x = POP ();
 359           PUSH (x + y);
 360           break;
 361
 362         case BINARY_SUBTRACT:
 363           y = POP ();
 364           x = POP ();
 365           PUSH (x - y);
 366           break;
 367
 368         case BINARY_MULT:
 369           y = POP ();
 370           x = POP ();
 371           PUSH (x * y);
 372           break;
 373
 374         case BINARY_COMPARE_LT:
 375           y = POP ();
 376           x = POP ();
 377           PUSH (x < y);
 378           break;
 379
 380         case RECURSE:
 381           x = POP ();
 382           x = interpret (x, trace);
 383           PUSH (x);
 384           break;
 385
 386         case RETURN:
 387           return POP ();
 388
 389           /* Ops taking an operand.  */
 390         case PUSH_CONST:
 391           PUSH (op->op_operand);
 392           break;
 393
 394         case JUMP_ABS_IF_TRUE:
 395           x = POP ();
 396           if (x)
 397             frame.frm_pc = op->op_operand;
 398           break;
 399
 400         default:
 401           assert (0); /* unknown opcode */
 402
 403         } /* end of switch on opcode */
 404     } /* end of while loop */
 405
 406 #undef PUSH
 407 #undef POP
 408 }
 409
 410 /* JIT compilation.  */
 411
 412 class compilation_state
 413 {
 414 public:
 415   compilation_state (toyvm_function &toyvmfn) :
 416     toyvmfn (toyvmfn)
 417   {}
 418
 419   void create_context ();
 420   void create_types ();
 421   void create_locations ();
 422   void create_function (const char *funcname);
 423   gcc_jit_result *compile ();
 424
 425 private:
 426   void
 427   add_push (gccjit::block block,
 428             gccjit::rvalue rvalue,
 429             gccjit::location loc);
 430
 431   void
 432   add_pop (gccjit::block block,
 433            gccjit::lvalue lvalue,
 434            gccjit::location loc);
 435
 436 private:
 437
 438   /* State.  */
 439
 440   toyvm_function &toyvmfn;
 441
 442   gccjit::context ctxt;
 443
 444   gccjit::type int_type;
 445   gccjit::type bool_type;
 446   gccjit::type stack_type; /* int[MAX_STACK_DEPTH] */
 447
 448   gccjit::rvalue const_one;
 449
 450   gccjit::function fn;
 451   gccjit::param param_arg;
 452   gccjit::lvalue stack;
 453   gccjit::lvalue stack_depth;
 454   gccjit::lvalue x;
 455   gccjit::lvalue y;
 456
 457   gccjit::location op_locs[MAX_OPS];
 458   gccjit::block initial_block;
 459   gccjit::block op_blocks[MAX_OPS];
 460
 461 };
 462
 463 /* The main compilation hook.  */
 464
 465 toyvm_compiled_func
 466 toyvm_function::compile ()
 467 {
 468   compilation_state state (*this);
 469   char *funcname;
 470
 471   funcname = get_function_name (fn_filename);
 472
 473   state.create_context ();
 474   state.create_types ();
 475   state.create_locations ();
 476   state.create_function (funcname);
 477
 478   /* We've now finished populating the context.  Compile it.  */
 479   gcc_jit_result *result = state.compile ();
 480
 481   return (toyvm_compiled_func)gcc_jit_result_get_code (result, funcname);
 482   /* (this leaks "result" and "funcname") */
 483 }
 484
 485 /* Stack manipulation.  */
 486
 487 void
 488 compilation_state::add_push (gccjit::block block,
 489                              gccjit::rvalue rvalue,
 490                              gccjit::location loc)
 491 {
 492   /* stack[stack_depth] = RVALUE */
 493   block.add_assignment (
 494     /* stack[stack_depth] */
 495     ctxt.new_array_access (
 496       stack,
 497       stack_depth,
 498       loc),
 499     rvalue,
 500     loc);
 501
 502   /* "stack_depth++;".  */
 503   block.add_assignment_op (
 504     stack_depth,
 505     GCC_JIT_BINARY_OP_PLUS,
 506     const_one,
 507     loc);
 508 }
 509
 510 void
 511 compilation_state::add_pop (gccjit::block block,
 512                             gccjit::lvalue lvalue,
 513                             gccjit::location loc)
 514 {
 515   /* "--stack_depth;".  */
 516   block.add_assignment_op (
 517     stack_depth,
 518     GCC_JIT_BINARY_OP_MINUS,
 519     const_one,
 520     loc);
 521
 522   /* "LVALUE = stack[stack_depth];".  */
 523   block.add_assignment (
 524     lvalue,
 525     /* stack[stack_depth] */
 526     ctxt.new_array_access (stack,
 527                            stack_depth,
 528                            loc),
 529     loc);
 530 }
 531
 532 /* Create the context. */
 533
 534 void
 535 compilation_state::create_context ()
 536 {
 537   ctxt = gccjit::context::acquire ();
 538
 539   ctxt.set_bool_option (GCC_JIT_BOOL_OPTION_DUMP_INITIAL_GIMPLE,
 540                               0);
 541   ctxt.set_bool_option (GCC_JIT_BOOL_OPTION_DUMP_GENERATED_CODE,
 542                               0);
 543   ctxt.set_int_option (GCC_JIT_INT_OPTION_OPTIMIZATION_LEVEL,
 544                              3);
 545   ctxt.set_bool_option (GCC_JIT_BOOL_OPTION_KEEP_INTERMEDIATES,
 546                               0);
 547   ctxt.set_bool_option (GCC_JIT_BOOL_OPTION_DUMP_EVERYTHING,
 548                               0);
 549   ctxt.set_bool_option (GCC_JIT_BOOL_OPTION_DEBUGINFO,
 550                               1);
 551 }
 552
 553 /* Create types.  */
 554
 555 void
 556 compilation_state::create_types ()
 557 {
 558   /* Create types.  */
 559   int_type = ctxt.get_type (GCC_JIT_TYPE_INT);
 560   bool_type = ctxt.get_type (GCC_JIT_TYPE_BOOL);
 561   stack_type = ctxt.new_array_type (int_type, MAX_STACK_DEPTH);
 562
 563   /* The constant value 1.  */
 564   const_one = ctxt.one (int_type);
 565
 566 }
 567
 568 /* Create locations.  */
 569
 570 void
 571 compilation_state::create_locations ()
 572 {
 573   for (int pc = 0; pc < toyvmfn.fn_num_ops; pc++)
 574     {
 575       toyvm_op *op = &toyvmfn.fn_ops[pc];
 576
 577       op_locs[pc] = ctxt.new_location (toyvmfn.fn_filename,
 578                                        op->op_linenum,
 579                                        0); /* column */
 580     }
 581 }
 582
 583 /* Creating the function.  */
 584
 585 void
 586 compilation_state::create_function (const char *funcname)
 587 {
 588   std::vector <gccjit::param> params;
 589   param_arg = ctxt.new_param (int_type, "arg", op_locs[0]);
 590   params.push_back (param_arg);
 591   fn = ctxt.new_function (GCC_JIT_FUNCTION_EXPORTED,
 592                           int_type,
 593                           funcname,
 594                           params, 0,
 595                           op_locs[0]);
 596
 597   /* Create stack lvalues.  */
 598   stack = fn.new_local (stack_type, "stack");
 599   stack_depth = fn.new_local (int_type, "stack_depth");
 600   x = fn.new_local (int_type, "x");
 601   y = fn.new_local (int_type, "y");
 602
 603   /* 1st pass: create blocks, one per opcode. */
 604
 605   /* We need an entry block to do one-time initialization, so create that
 606      first.  */
 607   initial_block = fn.new_block ("initial");
 608
 609   /* Create a block per operation.  */
 610   for (int pc = 0; pc < toyvmfn.fn_num_ops; pc++)
 611     {
 612       char buf[16];
 613       sprintf (buf, "instr%i", pc);
 614       op_blocks[pc] = fn.new_block (buf);
 615     }
 616
 617   /* Populate the initial block.  */
 618
 619   /* "stack_depth = 0;".  */
 620   initial_block.add_assignment (stack_depth,
 621                                 ctxt.zero (int_type),
 622                                 op_locs[0]);
 623
 624   /* "PUSH (arg);".  */
 625   add_push (initial_block,
 626             param_arg,
 627             op_locs[0]);
 628
 629   /* ...and jump to insn 0.  */
 630   initial_block.end_with_jump (op_blocks[0],
 631                                op_locs[0]);
 632
 633   /* 2nd pass: fill in instructions.  */
 634   for (int pc = 0; pc < toyvmfn.fn_num_ops; pc++)
 635     {
 636       gccjit::location loc = op_locs[pc];
 637
 638       gccjit::block block = op_blocks[pc];
 639       gccjit::block next_block = (pc < toyvmfn.fn_num_ops
 640                                   ? op_blocks[pc + 1]
 641                                   : NULL);
 642
 643       toyvm_op *op;
 644       op = &toyvmfn.fn_ops[pc];
 645
 646       /* Helper macros.  */
 647
 648 #define X_EQUALS_POP()\
 649       add_pop (block, x, loc)
 650 #define Y_EQUALS_POP()\
 651       add_pop (block, y, loc)
 652 #define PUSH_RVALUE(RVALUE)\
 653       add_push (block, (RVALUE), loc)
 654 #define PUSH_X()\
 655       PUSH_RVALUE (x)
 656 #define PUSH_Y() \
 657       PUSH_RVALUE (y)
 658
 659       block.add_comment (opcode_names[op->op_opcode], loc);
 660
 661       /* Handle the individual opcodes.  */
 662
 663       switch (op->op_opcode)
 664         {
 665         case DUP:
 666           X_EQUALS_POP ();
 667           PUSH_X ();
 668           PUSH_X ();
 669           break;
 670
 671         case ROT:
 672           Y_EQUALS_POP ();
 673           X_EQUALS_POP ();
 674           PUSH_Y ();
 675           PUSH_X ();
 676           break;
 677
 678         case BINARY_ADD:
 679           Y_EQUALS_POP ();
 680           X_EQUALS_POP ();
 681           PUSH_RVALUE (
 682            ctxt.new_binary_op (
 683              GCC_JIT_BINARY_OP_PLUS,
 684              int_type,
 685              x, y,
 686              loc));
 687           break;
 688
 689         case BINARY_SUBTRACT:
 690           Y_EQUALS_POP ();
 691           X_EQUALS_POP ();
 692           PUSH_RVALUE (
 693            ctxt.new_binary_op (
 694              GCC_JIT_BINARY_OP_MINUS,
 695              int_type,
 696              x, y,
 697              loc));
 698           break;
 699
 700         case BINARY_MULT:
 701           Y_EQUALS_POP ();
 702           X_EQUALS_POP ();
 703           PUSH_RVALUE (
 704            ctxt.new_binary_op (
 705              GCC_JIT_BINARY_OP_MULT,
 706              int_type,
 707              x, y,
 708              loc));
 709           break;
 710
 711         case BINARY_COMPARE_LT:
 712           Y_EQUALS_POP ();
 713           X_EQUALS_POP ();
 714           PUSH_RVALUE (
 715              /* cast of bool to int */
 716              ctxt.new_cast (
 717                /* (x < y) as a bool */
 718                ctxt.new_comparison (
 719                  GCC_JIT_COMPARISON_LT,
 720                  x, y,
 721                  loc),
 722                int_type,
 723                loc));
 724           break;
 725
 726         case RECURSE:
 727           {
 728             X_EQUALS_POP ();
 729             PUSH_RVALUE (
 730               ctxt.new_call (
 731                 fn,
 732                 x,
 733                 loc));
 734             break;
 735           }
 736
 737         case RETURN:
 738           X_EQUALS_POP ();
 739           block.end_with_return (x, loc);
 740           break;
 741
 742           /* Ops taking an operand.  */
 743         case PUSH_CONST:
 744           PUSH_RVALUE (
 745             ctxt.new_rvalue (int_type, op->op_operand));
 746           break;
 747
 748         case JUMP_ABS_IF_TRUE:
 749           X_EQUALS_POP ();
 750           block.end_with_conditional (
 751             /* "(bool)x".  */
 752             ctxt.new_cast (x, bool_type, loc),
 753             op_blocks[op->op_operand], /* on_true */
 754             next_block, /* on_false */
 755             loc);
 756           break;
 757
 758         default:
 759           assert(0);
 760         } /* end of switch on opcode */
 761
 762       /* Go to the next block.  */
 763       if (op->op_opcode != JUMP_ABS_IF_TRUE
 764           && op->op_opcode != RETURN)
 765         block.end_with_jump (next_block, loc);
 766
 767     } /* end of loop on PC locations.  */
 768 }
 769
 770 gcc_jit_result *
 771 compilation_state::compile ()
 772 {
 773   return ctxt.compile ();
 774 }
 775
 776 char test[1024];
 777
 778 #define CHECK_NON_NULL(PTR) \
 779   do {                                       \
 780     if ((PTR) != NULL)                       \
 781       {                                      \
 782         pass ("%s: %s is non-null", test, #PTR); \
 783       }                                      \
 784     else                                     \
 785       {                                      \
 786         fail ("%s: %s is NULL", test, #PTR); \
 787         abort ();                            \
 788     }                                        \
 789   } while (0)
 790
 791 #define CHECK_VALUE(ACTUAL, EXPECTED) \
 792   do {                                       \
 793     if ((ACTUAL) == (EXPECTED))              \
 794       {                                      \
 795         pass ("%s: actual: %s == expected: %s", test, #ACTUAL, #EXPECTED); \
 796       }                                      \
 797     else                                     \
 798       {                                        \
 799         fail ("%s: actual: %s != expected: %s", test, #ACTUAL, #EXPECTED); \
 800         fprintf (stderr, "incorrect value\n"); \
 801         abort ();                              \
 802     }                                        \
 803   } while (0)
 804
 805 static void
 806 test_script (const char *scripts_dir, const char *script_name, int input,
 807              int expected_result)
 808 {
 809   char *script_path;
 810   toyvm_function *fn;
 811   int interpreted_result;
 812   toyvm_compiled_func code;
 813   int compiled_result;
 814
 815   snprintf (test, sizeof (test), "toyvm.cc: %s", script_name);
 816
 817   script_path = (char *)malloc (strlen (scripts_dir)
 818                                 + strlen (script_name) + 1);
 819   CHECK_NON_NULL (script_path);
 820   sprintf (script_path, "%s%s", scripts_dir, script_name);
 821
 822   fn = toyvm_function::parse (script_path, script_name);
 823   CHECK_NON_NULL (fn);
 824
 825   interpreted_result = fn->interpret (input, NULL);
 826   CHECK_VALUE (interpreted_result, expected_result);
 827
 828   code = fn->compile ();
 829   CHECK_NON_NULL (code);
 830
 831   compiled_result = code (input);
 832   CHECK_VALUE (compiled_result, expected_result);
 833
 834   free (script_path);
 835 }
 836
 837 #define PATH_TO_SCRIPTS  ("/jit/docs/examples/tut04-toyvm/")
 838
 839 static void
 840 test_suite (void)
 841 {
 842   const char *srcdir;
 843   char *scripts_dir;
 844
 845   snprintf (test, sizeof (test), "toyvm.cc");
 846
 847   /* We need to locate the test scripts.
 848      Rely on "srcdir" being set in the environment.  */
 849
 850   srcdir = getenv ("srcdir");
 851   CHECK_NON_NULL (srcdir);
 852
 853   scripts_dir = (char *)malloc (strlen (srcdir) + strlen(PATH_TO_SCRIPTS)
 854                                 + 1);
 855   CHECK_NON_NULL (scripts_dir);
 856   sprintf (scripts_dir, "%s%s", srcdir, PATH_TO_SCRIPTS);
 857
 858   test_script (scripts_dir, "factorial.toy", 10, 3628800);
 859   test_script (scripts_dir, "fibonacci.toy", 10, 55);
 860
 861   free (scripts_dir);
 862 }
 863
 864 int
 865 main (int argc, char **argv)
 866 {
 867   const char *filename = NULL;
 868   toyvm_function *fn = NULL;
 869
 870   /* If called with no args, assume we're being run by the test suite.  */
 871   if (argc < 3)
 872     {
 873       test_suite ();
 874       return 0;
 875     }
 876
 877   if (argc != 3)
 878     {
 879       fprintf (stdout,
 880         "%s FILENAME INPUT: Parse and run a .toy file\n",
 881         argv[0]);
 882       exit (1);
 883     }
 884
 885   filename = argv[1];
 886   fn = toyvm_function::parse (filename, filename);
 887   if (!fn)
 888     exit (1);
 889
 890   if (0)
 891     fn->disassemble (stdout);
 892
 893   printf ("interpreter result: %d\n",
 894           fn->interpret (atoi (argv[2]), NULL));
 895
 896   /* JIT-compilation.  */
 897   toyvm_compiled_func code = fn->compile ();
 898   printf ("compiler result: %d\n",
 899           code (atoi (argv[2])));
 900
 901  return 0;
 902 }