src/vm/jit/verify/typecheck-stackbased.c

   1 /* src/vm/jit/verify/typecheck-stackbased.c - stack-based verifier
   2
   3    Copyright (C) 1996-2005, 2006, 2007 R. Grafl, A. Krall, C. Kruegel,
   4    C. Oates, R. Obermaisser, M. Platter, M. Probst, S. Ring,
   5    E. Steiner, C. Thalinger, D. Thuernbeck, P. Tomsich, C. Ullrich,
   6    J. Wenninger, Institut f. Computersprachen - TU Wien
   7
   8    This file is part of CACAO.
   9
  10    This program is free software; you can redistribute it and/or
  11    modify it under the terms of the GNU General Public License as
  12    published by the Free Software Foundation; either version 2, or (at
  13    your option) any later version.
  14
  15    This program is distributed in the hope that it will be useful, but
  16    WITHOUT ANY WARRANTY; without even the implied warranty of
  17    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  18    General Public License for more details.
  19
  20    You should have received a copy of the GNU General Public License
  21    along with this program; if not, write to the Free Software
  22    Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  23    02110-1301, USA.
  24
  25    $Id$
  26
  27 */
  28
  29
  30 #include "config.h"
  31
  32 #include <assert.h>
  33
  34 #include "vm/types.h"
  35
  36 #include "vm/builtin.h"
  37 #include "mm/memory.h"
  38
  39 #include "vm/global.h"
  40 #include "vm/primitive.h"
  41
  42 #include "vm/jit/parse.h"
  43 #include "vm/jit/show.h"
  44 #include "vm/jit/stack.h"
  45 #include "vm/jit/verify/typecheck-common.h"
  46
  47
  48 /* this #if runs over the whole file: */
  49 #if defined(ENABLE_VERIFIER)
  50
  51 typedef typedescriptor verifier_slot_t;
  52
  53 #if defined(TYPECHECK_VERBOSE)
  54 static void typecheck_stackbased_show_state(verifier_state *state,
  55                                                                                         typedescriptor *stack,
  56                                                                                         typedescriptor *stackfloor,
  57                                                                                         bool showins);
  58 #endif
  59
  60
  61 #define CHECK_STACK_DEPTH(d)                                         \
  62     if (((u1*)stack - (u1*)stackfloor)                               \
  63             < (((d)-1) * (int)sizeof(verifier_slot_t)))              \
  64         goto throw_stack_underflow;
  65
  66 /* XXX don't need to check against ACONST for every ICMD */
  67 #define CHECK_STACK_SPACE(d)                                         \
  68     if (((u1*)STATE->stackceiling - (u1*)stack)                      \
  69             < (((d)+1) * (int)sizeof(verifier_slot_t)))              \
  70         if (STATE->iptr->opc != ICMD_ACONST                          \
  71                 || INSTRUCTION_MUST_CHECK(STATE->iptr))              \
  72             goto throw_stack_overflow;
  73
  74 #define CHECK_STACK_TYPE(s, t)                                       \
  75     if ((s).type != (t))                                             \
  76         goto throw_stack_type_error;
  77
  78 /* XXX inefficient */
  79 #define CHECK_LOCAL_TYPE(index, t)                                   \
  80     do {                                                             \
  81         if (state.locals[(index)].type != (t))                       \
  82             goto throw_local_type_error;                             \
  83         if (STATE->topjsr)                                           \
  84             STATE->topjsr->usedlocals[(index)] = 1;                  \
  85         if (STATE->topjsr && IS_2_WORD_TYPE(t))                      \
  86             STATE->topjsr->usedlocals[(index) + 1] = 1;              \
  87     } while(0)
  88
  89 /* XXX inefficient */
  90 #define STORE_LOCAL(t, index)                                        \
  91     do {                                                             \
  92         state.locals[(index)].type = (t);                            \
  93         if ((index) && IS_2_WORD_TYPE(state.locals[(index)-1].type)) \
  94             state.locals[(index-1)].type = TYPE_VOID;                \
  95         if (STATE->topjsr)                                           \
  96             STATE->topjsr->usedlocals[(index)] = 1;                  \
  97     } while (0)
  98
  99 /* XXX inefficient */
 100 #define STORE_LOCAL_2_WORD(t, index)                                 \
 101     do {                                                             \
 102         STORE_LOCAL(t, index);                                       \
 103         state.locals[(index)+1].type = TYPE_VOID;                    \
 104         if (STATE->topjsr)                                           \
 105             STATE->topjsr->usedlocals[(index)] = 1;                  \
 106     } while (0)
 107
 108 #define VERIFY_ERROR(msg)                                            \
 109     do {                                                             \
 110         LOG1("VerifyError: %s", msg);                                \
 111         exceptions_throw_verifyerror(STATE->m, msg);                 \
 112         return false;                                                \
 113     } while (0)
 114
 115 #define IS_CAT1(slot)                                                \
 116     ((slot).type != TYPE_VOID && !IS_2_WORD_TYPE((slot).type))
 117
 118 #define IS_CAT2(slot)                                                \
 119     ((slot).type != TYPE_VOID && IS_2_WORD_TYPE((slot).type))
 120
 121 #define CHECK_CAT1(slot)                                             \
 122     do {                                                             \
 123         if (!IS_CAT1(slot))                                          \
 124             goto throw_stack_category_error;                         \
 125     } while (0)
 126
 127 #define CHECK_CAT2(slot)                                             \
 128     do {                                                             \
 129         if (!IS_CAT2(slot))                                          \
 130             goto throw_stack_category_error;                         \
 131     } while (0)
 132
 133 #define COPY_SLOT(s, d)                                              \
 134     do { (d) = (s); } while (0)
 135
 136 #define REACH_BLOCK(target)                                          \
 137     do {                                                             \
 138         if (!typecheck_stackbased_reach(STATE, (target), stack,      \
 139                     (stack - stackfloor) + 1))                       \
 140             return false;                                            \
 141     } while (0)
 142
 143 #define REACH(target)                                                \
 144     do {                                                             \
 145         REACH_BLOCK((target).block);                                 \
 146     } while (0)
 147
 148 #undef TYPECHECK_INT
 149 #undef TYPECHECK_LNG
 150 #undef TYPECHECK_FLT
 151 #undef TYPECHECK_DBL
 152 #undef TYPECHECK_ADR
 153
 154 /* XXX should reuse typevector code */
 155 static typecheck_result typecheck_stackbased_merge_locals(methodinfo *m,
 156                                                                                                                   typedescriptor *dst,
 157                                                                                                                   typedescriptor *y,
 158                                                                                                                   int size)
 159 {
 160         bool changed = false;
 161         typecheck_result r;
 162
 163         typedescriptor *a = dst;
 164         typedescriptor *b = y;
 165         while (size--) {
 166                 if (a->type != TYPE_VOID && a->type != b->type) {
 167                         a->type = TYPE_VOID;
 168                         changed = true;
 169                 }
 170                 else if (a->type == TYPE_ADR) {
 171                         if (TYPEINFO_IS_PRIMITIVE(a->typeinfo)) {
 172                                 /* 'a' is a returnAddress */
 173                                 if (!TYPEINFO_IS_PRIMITIVE(b->typeinfo)
 174                                         || (TYPEINFO_RETURNADDRESS(a->typeinfo)
 175                                                 != TYPEINFO_RETURNADDRESS(b->typeinfo)))
 176                                 {
 177                                         a->type = TYPE_VOID;
 178                                         changed = true;
 179                                 }
 180                         }
 181                         else {
 182                                 /* 'a' is a reference */
 183                                 if (TYPEINFO_IS_PRIMITIVE(b->typeinfo)) {
 184                                         a->type = TYPE_VOID;
 185                                         changed = true;
 186                                 }
 187                                 else {
 188                                         /* two reference types are merged. There cannot be */
 189                                         /* a merge error. In the worst case we get j.l.O.  */
 190                                         r = typeinfo_merge(m,&(a->typeinfo),&(b->typeinfo));
 191                                         if (r == typecheck_FAIL)
 192                                                 return r;
 193                                         changed |= r;
 194                                 }
 195                         }
 196                 }
 197                 a++;
 198                 b++;
 199         }
 200         return changed;
 201 }
 202
 203 static typecheck_result typecheck_stackbased_merge(verifier_state *state,
 204                                                                                                    basicblock *destblock,
 205                                                                                                    typedescriptor *stack,
 206                                                                                                    s4 stackdepth)
 207 {
 208         s4 i;
 209         s4 destidx;
 210         typedescriptor *stackfloor;
 211         typedescriptor *sp;
 212         typedescriptor *dp;
 213         typecheck_result r;
 214         bool changed = false;
 215
 216         destidx = destblock->nr;
 217
 218         if (stackdepth != state->indepth[destidx]) {
 219                 exceptions_throw_verifyerror(state->m, "Stack depth mismatch");
 220                 return typecheck_FAIL;
 221         }
 222
 223         stackfloor = stack - (stackdepth - 1);
 224
 225         sp = stackfloor;
 226         dp = state->startstack + (destidx * state->m->maxstack);
 227
 228         for (i=0; i<stackdepth; ++i, ++sp, ++dp) {
 229                 if (sp->type != dp->type) {
 230                         exceptions_throw_verifyerror(state->m, "Mismatched stack types");
 231                         return typecheck_FAIL;
 232                 }
 233                 if (dp->type == TYPE_ADR) {
 234                         if (TYPEINFO_IS_PRIMITIVE(dp->typeinfo)) {
 235                                 /* dp has returnAddress type */
 236                                 if (TYPEINFO_IS_PRIMITIVE(sp->typeinfo)) {
 237                                         if (TYPEINFO_RETURNADDRESS(dp->typeinfo) != TYPEINFO_RETURNADDRESS(sp->typeinfo)) {
 238                                                 exceptions_throw_verifyerror(state->m, "Mismatched stack types");
 239                                                 return typecheck_FAIL;
 240                                         }
 241                                 }
 242                                 else {
 243                                         exceptions_throw_verifyerror(state->m,"Merging returnAddress with reference");
 244                                         return typecheck_FAIL;
 245                                 }
 246                         }
 247                         else {
 248                                 /* dp has reference type */
 249                                 if (TYPEINFO_IS_PRIMITIVE(sp->typeinfo)) {
 250                                         exceptions_throw_verifyerror(state->m,"Merging reference with returnAddress");
 251                                         return typecheck_FAIL;
 252                                 }
 253                                 r = typeinfo_merge(state->m,&(dp->typeinfo),&(sp->typeinfo));
 254                                 if (r == typecheck_FAIL)
 255                                         return r;
 256                                 changed |= r;
 257                         }
 258                 }
 259         }
 260
 261         dp = state->startlocals + (destidx * state->numlocals);
 262         r = typecheck_stackbased_merge_locals(state->m, dp, state->locals, state->numlocals);
 263         if (r == typecheck_FAIL)
 264                 return r;
 265         changed |= r;
 266
 267         return changed;
 268 }
 269
 270 static bool typecheck_stackbased_reach(verifier_state *state,
 271                                                                            basicblock *destblock,
 272                                                                            typedescriptor *stack,
 273                                                                            s4 stackdepth)
 274 {
 275         bool changed = false;
 276         typecheck_result r;
 277
 278         assert(destblock);
 279
 280         if (destblock->flags == BBTYPECHECK_UNDEF) {
 281                 /* The destblock has never been reached before */
 282
 283                 TYPECHECK_COUNT(stat_copied);
 284                 LOG1("block L%03d reached first time",destblock->nr); LOGSTR("\t");
 285                 DOLOG( typecheck_stackbased_show_state(state, stack, stack - (stackdepth - 1), false); );
 286
 287                 state->indepth[destblock->nr] = stackdepth;
 288
 289                 MCOPY(state->startstack + (destblock->nr * state->m->maxstack),
 290                           stack - (stackdepth - 1),
 291                           typedescriptor,
 292                           stackdepth);
 293
 294                 MCOPY(state->startlocals + (destblock->nr * state->numlocals),
 295                           state->locals,
 296                           typedescriptor,
 297                           state->numlocals);
 298
 299                 changed = true;
 300         }
 301         else {
 302                 /* The destblock has already been reached before */
 303
 304                 TYPECHECK_COUNT(stat_merged);
 305                 LOG1("block L%03d reached before", destblock->nr); LOGSTR("\t");
 306                 DOLOG( typecheck_stackbased_show_state(state, stack, stack - (stackdepth - 1), false); );
 307
 308                 r = typecheck_stackbased_merge(state, destblock, stack, stackdepth);
 309                 if (r == typecheck_FAIL)
 310                         return false;
 311                 changed = r;
 312
 313                 TYPECHECK_COUNTIF(changed,stat_merging_changed);
 314         }
 315
 316         if (changed) {
 317                 LOG("\tchanged!");
 318                 destblock->flags = BBTYPECHECK_REACHED;
 319                 /* XXX is this check ok? */
 320                 if (destblock->nr <= state->bptr->nr) {
 321                         LOG("\tREPEAT!");
 322                         state->repeat = true;
 323                 }
 324         }
 325         return true;
 326 }
 327
 328
 329 /* typecheck_stackbased_verify_fieldaccess *************************************
 330
 331    Verify an ICMD_{GET,PUT}{STATIC,FIELD}
 332
 333    IN:
 334        state............the current state of the verifier
 335            instance.........the instance slot, or NULL
 336            value............the value slot, or NULL
 337            stack............stack after popping the arguments
 338
 339    RETURN VALUE:
 340        stack pointer....successful verification,
 341            NULL.............an exception has been thrown.
 342
 343 *******************************************************************************/
 344
 345 static typedescriptor *typecheck_stackbased_verify_fieldaccess(
 346                 verifier_state *state,
 347                 typedescriptor *instance,
 348                 typedescriptor *value,
 349                 typedescriptor *stack)
 350 {
 351         jitdata *jd;
 352
 353         jd = state->jd;
 354
 355 #define TYPECHECK_STACKBASED
 356 #define EXCEPTION  do { return NULL; } while (0)
 357 #define STATE  state
 358 #include <typecheck-fields.inc>
 359 #undef  EXCEPTION
 360 #undef  STATE
 361 #undef  TYPECHECK_STACKBASED
 362
 363         return stack;
 364
 365 throw_stack_overflow:
 366         LOG("STACK OVERFLOW!");
 367         exceptions_throw_verifyerror(state->m, "Stack size too large");
 368         return NULL;
 369 }
 370
 371 static bool typecheck_stackbased_verify_invocation(verifier_state *state,
 372                                                                                                    typedescriptor *stack,
 373                                                                                                    typedescriptor *stackfloor)
 374 {
 375         s4 paramslots;
 376         methoddesc *md;
 377         typedescriptor *dv;
 378
 379         /* check stack depth */
 380
 381         /* XXX parse params */
 382
 383         INSTRUCTION_GET_METHODDESC(state->iptr, md);
 384
 385         paramslots = md->paramslots;
 386
 387         if ((stack - stackfloor) + 1 < paramslots) {
 388                 exceptions_throw_verifyerror(state->m,
 389                                 "Trying to pop operand of an empty stack");
 390                 return false;
 391         }
 392
 393         dv = stack - (paramslots - 1);
 394
 395 #define TYPECHECK_STACKBASED
 396 #define OP1   dv
 397 #include <typecheck-invoke.inc>
 398 #undef  OP1
 399 #undef  TYPECHECK_STACKBASED
 400
 401         return true;
 402 }
 403
 404 static bool typecheck_stackbased_verify_builtin(verifier_state *state,
 405                                                                                                 typedescriptor *stack,
 406                                                                                                 typedescriptor *stackfloor)
 407 {
 408         s4 paramslots;
 409         typedescriptor *dv;
 410
 411         /* check stack depth */
 412
 413         /* XXX parse params */
 414
 415         paramslots = state->iptr->sx.s23.s3.bte->md->paramslots;
 416
 417         if ((stack - stackfloor) + 1 < paramslots) {
 418                 exceptions_throw_verifyerror(state->m,
 419                                 "Trying to pop operand of an empty stack");
 420                 return false;
 421         }
 422
 423         dv = stack - (paramslots - 1);
 424
 425 #define TYPECHECK_STACKBASED
 426 #define OP1   dv
 427 #define TYPECHECK_INT(s)  CHECK_STACK_TYPE(*(s), TYPE_INT)
 428 #define TYPECHECK_ADR(s)  CHECK_STACK_TYPE(*(s), TYPE_ADR)
 429 #define TYPECHECK_LNG(s)  CHECK_STACK_TYPE(*(s), TYPE_LNG)
 430 #define TYPECHECK_FLT(s)  CHECK_STACK_TYPE(*(s), TYPE_FLT)
 431 #define TYPECHECK_DBL(s)  CHECK_STACK_TYPE(*(s), TYPE_DBL)
 432 #include <typecheck-builtins.inc>
 433 #undef  OP1
 434 #undef  TYPECHECK_STACKBASED
 435
 436         return true;
 437
 438 throw_stack_type_error:
 439         exceptions_throw_verifyerror(state->m, "Wrong type on stack"); /* XXX */
 440         return false;
 441 }
 442
 443 static bool typecheck_stackbased_multianewarray(verifier_state *state,
 444                                                                                                 typedescriptor *stack,
 445                                                                                                 typedescriptor *stackfloor)
 446 {
 447         /* XXX recombine with verify_multianewarray */
 448
 449         classinfo *arrayclass;
 450         arraydescriptor *desc;
 451         s4 i;
 452         typedescriptor *sp;
 453         typedescriptor *dst;
 454
 455         /* destination slot */
 456
 457         i = state->iptr->s1.argcount;
 458
 459         dst = stack - (i-1);
 460
 461         /* check the array lengths on the stack */
 462
 463         if ((stack - stackfloor) + 1 < i) {
 464                 exceptions_throw_verifyerror(state->m,
 465                                 "Trying to pop operand of an empty stack");
 466                 return false;
 467         }
 468
 469         if (i < 1)
 470                 TYPECHECK_VERIFYERROR_bool("Illegal dimension argument");
 471
 472         for (sp = dst; sp <= stack; ++sp) {
 473                 if (sp->type != TYPE_INT) {
 474                         exceptions_throw_verifyerror_for_stack(state->m, TYPE_INT);
 475                         return false;
 476                 }
 477         }
 478
 479         /* check array descriptor */
 480
 481         if (INSTRUCTION_IS_RESOLVED(state->iptr)) {
 482                 /* the array class reference has already been resolved */
 483                 arrayclass = state->iptr->sx.s23.s3.c.cls;
 484                 if (!arrayclass)
 485                         TYPECHECK_VERIFYERROR_bool("MULTIANEWARRAY with unlinked class");
 486                 if ((desc = arrayclass->vftbl->arraydesc) == NULL)
 487                         TYPECHECK_VERIFYERROR_bool("MULTIANEWARRAY with non-array class");
 488                 if (desc->dimension < state->iptr->s1.argcount)
 489                         TYPECHECK_VERIFYERROR_bool("MULTIANEWARRAY dimension to high");
 490
 491                 /* set the array type of the result */
 492                 typeinfo_init_classinfo(&(dst->typeinfo), arrayclass);
 493         }
 494         else {
 495                 const char *p;
 496                 constant_classref *cr;
 497
 498                 /* the array class reference is still unresolved */
 499                 /* check that the reference indicates an array class of correct dimension */
 500                 cr = state->iptr->sx.s23.s3.c.ref;
 501                 i = 0;
 502                 p = cr->name->text;
 503                 while (p[i] == '[')
 504                         i++;
 505                 /* { the dimension of the array class == i } */
 506                 if (i < 1)
 507                         TYPECHECK_VERIFYERROR_bool("MULTIANEWARRAY with non-array class");
 508                 if (i < state->iptr->s1.argcount)
 509                         TYPECHECK_VERIFYERROR_bool("MULTIANEWARRAY dimension to high");
 510
 511                 /* set the array type of the result */
 512                 if (!typeinfo_init_class(&(dst->typeinfo),CLASSREF_OR_CLASSINFO(cr)))
 513                         return false;
 514         }
 515
 516         /* everything ok */
 517         return true;
 518
 519 }
 520
 521 static void typecheck_stackbased_add_jsr_caller(typecheck_jsr_t *jsr,
 522                                                                                                 basicblock *bptr)
 523 {
 524         typecheck_jsr_caller_t *jc;
 525
 526         for (jc = jsr->callers; jc; jc = jc->next)
 527                 if (jc->callblock == bptr)
 528                         return;
 529
 530         jc = DNEW(typecheck_jsr_caller_t);
 531         jc->next = jsr->callers;
 532         jc->callblock = bptr;
 533         jsr->callers = jc;
 534 }
 535
 536 static typedescriptor *typecheck_stackbased_jsr(verifier_state *state,
 537                                                                                                 typedescriptor *stack,
 538                                                                                                 typedescriptor *stackfloor)
 539 {
 540         typecheck_jsr_t *jsr;
 541         basicblock *tbptr;
 542         jitdata *jd;
 543         s4 i;
 544
 545         jd = state->jd;
 546
 547         tbptr = state->iptr->sx.s23.s3.jsrtarget.block;
 548         jsr = state->jsrinfos[tbptr->nr];
 549
 550         if (jsr && tbptr->flags == BBFINISHED) {
 551
 552                 LOG1("another JSR to analysed subroutine L%03d", tbptr->nr);
 553                 if (jsr->active) {
 554                         exceptions_throw_verifyerror(state->m, "Recursive JSR");
 555                         return NULL;
 556                 }
 557
 558                 assert(jsr->callers);
 559                 assert(jsr->callers->callblock);
 560
 561                 /* copy the stack of the RET edge */
 562
 563                 MCOPY(stackfloor, jsr->retstack, typedescriptor, jsr->retdepth);
 564                 stack = stackfloor + (jsr->retdepth - 1);
 565
 566                 /* copy variables that were used in the subroutine from the RET edge */
 567
 568                 for (i=0; i<state->numlocals; ++i)
 569                         if (jsr->usedlocals[i])
 570                                 state->locals[i] = jsr->retlocals[i];
 571
 572                 /* reach the following block */
 573
 574                 if (!typecheck_stackbased_reach(state, state->bptr->next, stack,
 575                                         (stack - stackfloor) + 1))
 576                         return NULL;
 577         }
 578         else {
 579                 if (!jsr) {
 580                         LOG1("first JSR to block L%03d", tbptr->nr);
 581
 582                         jsr = DNEW(typecheck_jsr_t);
 583                         state->jsrinfos[tbptr->nr] = jsr;
 584                         jsr->callers = NULL;
 585                         jsr->blockflags = DMNEW(char, state->basicblockcount);
 586                         jsr->retblock = NULL;
 587                         jsr->start = tbptr;
 588                         jsr->usedlocals = DMNEW(char, state->numlocals);
 589                         MZERO(jsr->usedlocals, char, state->numlocals);
 590                         jsr->retlocals = DMNEW(typedescriptor, state->numlocals);
 591                         jsr->retstack = DMNEW(typedescriptor, state->m->maxstack);
 592                         jsr->retdepth = 0;
 593                 }
 594                 else {
 595                         LOG1("re-analysing JSR to block L%03d", tbptr->nr);
 596                 }
 597
 598                 jsr->active = true;
 599                 jsr->next = state->topjsr;
 600                 state->topjsr = jsr;
 601
 602                 assert(state->iptr->sx.s23.s3.jsrtarget.block->flags == BBTYPECHECK_REACHED);
 603
 604                 tbptr->flags = BBFINISHED;
 605
 606                 for (tbptr = state->basicblocks; tbptr != NULL; tbptr = tbptr->next) {
 607                         jsr->blockflags[tbptr->nr] = tbptr->flags;
 608
 609                         if (tbptr->flags == BBTYPECHECK_REACHED)
 610                                 tbptr->flags = BBFINISHED;
 611                 }
 612
 613                 state->iptr->sx.s23.s3.jsrtarget.block->flags = BBTYPECHECK_REACHED;
 614         }
 615
 616         /* register this block as a caller, if not already done */
 617
 618         typecheck_stackbased_add_jsr_caller(jsr, state->bptr);
 619
 620         return stack;
 621 }
 622
 623 static bool typecheck_stackbased_ret(verifier_state *state,
 624                                                                          typedescriptor *stack,
 625                                                                          typedescriptor *stackfloor)
 626 {
 627         basicblock *tbptr;
 628         typecheck_jsr_caller_t *jsrcaller;
 629         typecheck_jsr_t *jsr;
 630         s4 i;
 631
 632         /* get the subroutine we are RETurning from */
 633
 634         tbptr = TYPEINFO_RETURNADDRESS(state->locals[state->iptr->s1.varindex].typeinfo);
 635         if (tbptr == NULL) {
 636                 exceptions_throw_verifyerror(state->m, "Illegal RET");
 637                 return false;
 638         }
 639
 640         LOG1("RET from subroutine L%03d", tbptr->nr);
 641         jsr = state->jsrinfos[tbptr->nr];
 642         assert(jsr);
 643
 644         /* check against recursion */
 645
 646         if (!jsr->active) {
 647                 exceptions_throw_verifyerror(state->m, "RET outside of local subroutine");
 648                 return false;
 649         }
 650
 651         /* check against multiple RETs for one subroutine */
 652
 653         if (jsr->retblock && jsr->retblock != state->bptr) {
 654                 exceptions_throw_verifyerror(state->m, "Multiple RETs from local subroutine");
 655                 return false;
 656         }
 657
 658         /* store data-flow of the RET edge */
 659
 660         jsr->retblock = state->bptr;
 661         jsr->retdepth = (stack - stackfloor) + 1;
 662         MCOPY(jsr->retstack, stackfloor, typedescriptor, jsr->retdepth);
 663         MCOPY(jsr->retlocals, state->locals, typedescriptor, state->numlocals);
 664
 665         /* invalidate the returnAddress used by this RET */
 666         /* XXX should we also invalidate the returnAddresses of JSRs that are skipped by this RET? */
 667
 668         for (i=0; i<state->numlocals; ++i) {
 669                 typedescriptor *lc = &(jsr->retlocals[i]);
 670                 if (TYPE_IS_RETURNADDRESS(lc->type, lc->typeinfo))
 671                         if (TYPEINFO_RETURNADDRESS(lc->typeinfo) == tbptr) {
 672                                 LOG1("invalidating returnAddress in local %d", i);
 673                                 TYPEINFO_INIT_RETURNADDRESS(lc->typeinfo, NULL);
 674                         }
 675         }
 676
 677         /* touch all callers of the subroutine, so they are analysed again */
 678
 679         for (jsrcaller = jsr->callers; jsrcaller != NULL; jsrcaller = jsrcaller->next) {
 680                 tbptr = jsrcaller->callblock;
 681                 LOG1("touching caller L%03d from RET", tbptr->nr);
 682                 assert(jsr->blockflags[tbptr->nr] >= BBFINISHED);
 683                 jsr->blockflags[tbptr->nr] = BBTYPECHECK_REACHED; /* XXX repeat? */
 684         }
 685
 686         return true;
 687 }
 688
 689 bool typecheck_stackbased(jitdata *jd)
 690 {
 691         register verifier_slot_t *stack;
 692         verifier_slot_t *stackfloor;
 693         s4 len;
 694         methoddesc *md;
 695         bool maythrow;
 696         bool superblockend;
 697         verifier_slot_t temp;
 698         branch_target_t *table;
 699         lookup_target_t *lookup;
 700         s4 i;
 701         typecheck_result r;
 702         verifier_slot_t *dst;
 703         verifier_state state;
 704         basicblock *tbptr;
 705         exception_entry *ex;
 706         typedescriptor exstack;
 707         s4 skip = 0;
 708
 709         DOLOG( show_method(jd, SHOW_PARSE); );
 710
 711         /* initialize verifier state */
 712
 713         state.jd = jd;
 714         state.m = jd->m;
 715         state.cd = jd->cd;
 716         state.basicblocks = jd->basicblocks;
 717         state.basicblockcount = jd->basicblockcount;
 718         state.topjsr = NULL;
 719 #   define STATE (&state)
 720
 721         /* check that the basicblock numbers are valid */
 722
 723 #if !defined(NDEBUG)
 724         jit_check_basicblock_numbers(jd);
 725 #endif
 726
 727         /* check if this method is an instance initializer method */
 728
 729     state.initmethod = (state.m->name == utf_init);
 730
 731         /* allocate parameter descriptors if necessary */
 732
 733         if (!state.m->parseddesc->params)
 734                 if (!descriptor_params_from_paramtypes(state.m->parseddesc,state.m->flags))
 735                         return false;
 736
 737         /* allocate the stack buffers */
 738
 739         stackfloor = DMNEW(verifier_slot_t, state.m->maxstack + 1);
 740         state.stackceiling = stackfloor + state.m->maxstack;
 741         stack = stackfloor - 1;
 742         state.indepth = DMNEW(s4, state.basicblockcount);
 743         state.startstack = DMNEW(verifier_slot_t, state.m->maxstack * state.basicblockcount);
 744
 745         /* allocate the local variables buffers */
 746
 747         state.numlocals = state.m->maxlocals;
 748         state.validlocals = state.m->maxlocals;
 749     if (state.initmethod)
 750                 state.numlocals++; /* extra marker variable */
 751
 752         state.locals = DMNEW(verifier_slot_t, state.numlocals);
 753         state.startlocals = DMNEW(verifier_slot_t, state.numlocals * state.basicblockcount);
 754
 755     /* allocate the buffer of active exception handlers */
 756
 757     state.handlers = DMNEW(exception_entry*, state.jd->exceptiontablelength + 1);
 758
 759     /* initialize instack of exception handlers */
 760
 761         exstack.type = TYPE_ADR;
 762         typeinfo_init_classinfo(&(exstack.typeinfo),
 763                                                         class_java_lang_Throwable); /* changed later */
 764
 765     LOG("Exception handler stacks set.\n");
 766
 767         /* initialize jsr info buffer */
 768
 769         state.jsrinfos = DMNEW(typecheck_jsr_t *, state.basicblockcount);
 770         MZERO(state.jsrinfos, typecheck_jsr_t *, state.basicblockcount);
 771
 772         /* initialize stack of first block */
 773
 774         state.indepth[0] = 0;
 775
 776         /* initialize locals of first block */
 777
 778     /* if this is an instance method initialize the "this" ref type */
 779
 780     if (!(state.m->flags & ACC_STATIC)) {
 781                 if (state.validlocals < 1)
 782                         VERIFY_ERROR("Not enough local variables for method arguments");
 783                 dst = state.startlocals;
 784                 dst->type = TYPE_ADR;
 785                 if (state.initmethod)
 786                         TYPEINFO_INIT_NEWOBJECT(dst->typeinfo, NULL);
 787                 else
 788                         typeinfo_init_classinfo(&(dst->typeinfo), state.m->class);
 789
 790                 skip = 1;
 791     }
 792
 793     LOG("'this' argument set.\n");
 794
 795         len = typedescriptors_init_from_methoddesc(state.startlocals + skip,
 796                         state.m->parseddesc,
 797                         state.validlocals, true, skip, &state.returntype);
 798         if (len < 0)
 799                 return false;
 800
 801         /* set remaining locals to void */
 802
 803         for (i = skip + len; i<state.numlocals; ++i)
 804                 state.startlocals[i].type = TYPE_VOID;
 805
 806         /* initialize block flags */
 807
 808         typecheck_init_flags(&state, BBUNDEF);
 809
 810         /* iterate until fixpoint reached */
 811
 812         do {
 813
 814                 state.repeat = false;
 815
 816                 /* iterate over the basic blocks */
 817
 818                 for (state.bptr = state.basicblocks; state.bptr != NULL; state.bptr = state.bptr->next) {
 819
 820                         if (state.bptr->flags != BBTYPECHECK_REACHED)
 821                                 continue;
 822
 823                         DOLOG( show_basicblock(jd, state.bptr, SHOW_PARSE); );
 824
 825                         /* mark this block as analysed */
 826
 827                         state.bptr->flags = BBFINISHED;
 828
 829                         /* determine the active exception handlers for this block */
 830                         /* XXX could use a faster algorithm with sorted lists or  */
 831                         /* something?                                             */
 832                         /* XXX reuse code from variables based verifer? */
 833                         len = 0;
 834                         for (ex = STATE->jd->exceptiontable; ex ; ex = ex->down) {
 835                                 if ((ex->start->nr <= STATE->bptr->nr) && (ex->end->nr > STATE->bptr->nr)) {
 836                                         LOG1("\tactive handler L%03d", ex->handler->nr);
 837                                         STATE->handlers[len++] = ex;
 838                                 }
 839                         }
 840                         STATE->handlers[len] = NULL;
 841
 842                         /* initialize the locals */
 843
 844                         MCOPY(state.locals,
 845                                   state.startlocals + (state.bptr->nr * state.numlocals),
 846                                   verifier_slot_t, state.numlocals);
 847
 848                         /* initialize the stack */
 849
 850                         len = state.indepth[state.bptr->nr];
 851
 852                         MCOPY(stackfloor,
 853                                   state.startstack + (state.bptr->nr * state.m->maxstack),
 854                                   verifier_slot_t, len);
 855
 856                         stack = stackfloor + (len - 1);
 857
 858                         /* iterate over the instructions in this block */
 859
 860                         state.iptr = state.bptr->iinstr;
 861                         len = state.bptr->icount;
 862
 863                         superblockend = false;
 864
 865                         for (; len--; state.iptr++) {
 866
 867                                 maythrow = false;
 868
 869                                 LOGNL;
 870                                 DOLOG( typecheck_stackbased_show_state(&state, stack, stackfloor, true); );
 871
 872                                 switch (state.iptr->opc) {
 873 #define TYPECHECK_STACKBASED 1
 874 #define STATE (&state)
 875 #define IPTR state.iptr
 876 #define BPTR state.bptr
 877 #define METHOD state.m
 878 #define LOCAL_SLOT(index)  (state.locals + (index))
 879 #define EXCEPTION                                                    \
 880     do {                                                             \
 881         LOG("EXCEPTION THROWN!\n");                                  \
 882         return false;                                                \
 883     } while (0)
 884
 885 #include <typecheck-stackbased-gen.inc>
 886 #undef  TYPECHECK_STACKBASED
 887                                 }
 888
 889                                 /* reach exception handlers for this instruction */
 890
 891                                 if (maythrow) {
 892                                         TYPECHECK_COUNT(stat_ins_maythrow);
 893                                         TYPECHECK_MARK(STATE->stat_maythrow);
 894                                         LOG("\treaching exception handlers");
 895                                         i = 0;
 896                                         while (STATE->handlers[i]) {
 897                                                 TYPECHECK_COUNT(stat_handlers_reached);
 898                                                 if (STATE->handlers[i]->catchtype.any)
 899                                                         exstack.typeinfo.typeclass = STATE->handlers[i]->catchtype;
 900                                                 else
 901                                                         exstack.typeinfo.typeclass.cls = class_java_lang_Throwable;
 902                                                 if (!typecheck_stackbased_reach(
 903                                                                 STATE,
 904                                                                 STATE->handlers[i]->handler,
 905                                                                 &exstack, 1))
 906                                                         EXCEPTION;
 907                                                 i++;
 908                                         }
 909                                 }
 910                         }
 911
 912                         /* propagate types to the following block */
 913
 914                         if (!superblockend) {
 915                                 if (!typecheck_stackbased_reach(&state, state.bptr->next,
 916                                                                                                 stack, stack - stackfloor + 1))
 917                                         EXCEPTION;
 918                         }
 919                 } /* end loop over blocks */
 920
 921                 while (!state.repeat && state.topjsr) {
 922                         LOG1("done analysing subroutine L%03d", state.topjsr->start->nr);
 923
 924                         /* propagate down used locals */
 925
 926                         if (state.topjsr->next) {
 927                                 for (i=0; i<state.numlocals; ++i)
 928                                         state.topjsr->next->usedlocals[i] |= state.topjsr->usedlocals[i];
 929                         }
 930
 931                         /* restore REACHED flags */
 932
 933                         for (tbptr = state.basicblocks; tbptr != NULL; tbptr = tbptr->next) {
 934                                 assert(tbptr->flags != BBTYPECHECK_REACHED);
 935                                 if (state.topjsr->blockflags[tbptr->nr] == BBTYPECHECK_REACHED) {
 936                                         tbptr->flags = BBTYPECHECK_REACHED;
 937                                         state.repeat = true;
 938                                 }
 939                         }
 940
 941                         /* dactivate the subroutine */
 942
 943                         state.topjsr->active = false;
 944                         state.topjsr = state.topjsr->next;
 945                 }
 946         } while (state.repeat);
 947
 948         /* reset block flags */
 949
 950         typecheck_reset_flags(&state);
 951
 952         LOG("typecheck_stackbased successful");
 953
 954         return true;
 955
 956 throw_stack_underflow:
 957         LOG("STACK UNDERFLOW!");
 958         exceptions_throw_verifyerror(state.m, "Unable to pop operand off an empty stack");
 959         return false;
 960
 961 throw_stack_overflow:
 962         LOG("STACK OVERFLOW!");
 963         exceptions_throw_verifyerror(state.m, "Stack size too large");
 964         return false;
 965
 966 throw_stack_type_error:
 967         LOG("STACK TYPE ERROR!");
 968         exceptions_throw_verifyerror(state.m, "Mismatched stack types");
 969         return false;
 970
 971 throw_local_type_error:
 972         LOG("LOCAL TYPE ERROR!");
 973         exceptions_throw_verifyerror(state.m, "Local variable type mismatch");
 974         return false;
 975
 976 throw_stack_category_error:
 977         LOG("STACK CATEGORY ERROR!");
 978         exceptions_throw_verifyerror(state.m, "Attempt to split long or double on the stack");
 979         return false;
 980 }
 981
 982
 983 #if defined(TYPECHECK_VERBOSE)
 984 static void typecheck_stackbased_show_state(verifier_state *state,
 985                                                                                         typedescriptor *stack,
 986                                                                                         typedescriptor *stackfloor,
 987                                                                                         bool showins)
 988 {
 989         typedescriptor *sp;
 990         s4 i;
 991
 992         LOGSTR1("stackdepth %d stack [", (stack - stackfloor) + 1);
 993         for (sp=stackfloor; sp <= stack; sp++) {
 994                 LOGSTR(" ");
 995                 DOLOG( typedescriptor_print(stdout, sp); );
 996         }
 997         LOGSTR(" ] locals [");
 998         for (i=0; i<state->numlocals; ++i) {
 999                 LOGSTR(" ");
1000                 DOLOG( typedescriptor_print(stdout, state->locals + i); );
1001         }
1002         LOGSTR(" ]");
1003         LOGNL;
1004         if (showins && state->iptr < (state->bptr->iinstr + state->bptr->icount)) {
1005                 LOGSTR("\t");
1006                 DOLOG( show_icmd(state->jd, state->iptr, false, SHOW_PARSE); );
1007                 LOGNL;
1008         }
1009 }
1010 #endif
1011
1012 #endif /* defined(ENABLE_VERIFIER) */
1013
1014
1015 /*
1016  * These are local overrides for various environment variables in Emacs.
1017  * Please do not remove this and leave it at the end of the file, where
1018  * Emacs will automagically detect them.
1019  * ---------------------------------------------------------------------
1020  * Local variables:
1021  * mode: c
1022  * indent-tabs-mode: t
1023  * c-basic-offset: 4
1024  * tab-width: 4
1025  * End:
1026  * vim:noexpandtab:sw=4:ts=4:
1027  */
1028