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, 2008
   4    CACAOVM - Verein zur Foerderung der freien virtuellen Maschine CACAO
   5
   6    This file is part of CACAO.
   7
   8    This program is free software; you can redistribute it and/or
   9    modify it under the terms of the GNU General Public License as
  10    published by the Free Software Foundation; either version 2, or (at
  11    your option) any later version.
  12
  13    This program is distributed in the hope that it will be useful, but
  14    WITHOUT ANY WARRANTY; without even the implied warranty of
  15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  16    General Public License for more details.
  17
  18    You should have received a copy of the GNU General Public License
  19    along with this program; if not, write to the Free Software
  20    Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  21    02110-1301, USA.
  22
  23 */
  24
  25
  26 #include "config.h"
  27
  28 #include <assert.h>
  29
  30 #include "vm/types.h"
  31
  32 #include "vm/jit/builtin.hpp"
  33 #include "mm/memory.h"
  34
  35 #include "vm/array.hpp"
  36 #include "vm/exceptions.hpp"
  37 #include "vm/global.h"
  38 #include "vm/globals.hpp"
  39 #include "vm/primitive.hpp"
  40
  41 #include "vm/jit/parse.h"
  42 #include "vm/jit/show.hpp"
  43 #include "vm/jit/stack.h"
  44 #include "vm/jit/verify/typecheck-common.h"
  45
  46
  47 /* this #if runs over the whole file: */
  48 #if defined(ENABLE_VERIFIER)
  49
  50 typedef typedescriptor_t verifier_slot_t;
  51
  52 #if defined(TYPECHECK_VERBOSE)
  53 static void typecheck_stackbased_show_state(verifier_state *state,
  54                                                                                         typedescriptor *stack,
  55                                                                                         typedescriptor *stackfloor,
  56                                                                                         bool showins);
  57 #endif
  58
  59
  60 #define CHECK_STACK_DEPTH(d)                                         \
  61     if (((u1*)stack - (u1*)stackfloor)                               \
  62             < (((d)-1) * (int)sizeof(verifier_slot_t)))              \
  63         goto throw_stack_underflow;
  64
  65 /* XXX don't need to check against ACONST for every ICMD */
  66 #define CHECK_STACK_SPACE(d)                                         \
  67     if (((u1*)STATE->stackceiling - (u1*)stack)                      \
  68             < (((d)+1) * (int)sizeof(verifier_slot_t)))              \
  69         if (STATE->iptr->opc != ICMD_ACONST                          \
  70                 || INSTRUCTION_MUST_CHECK(STATE->iptr))              \
  71             goto throw_stack_overflow;
  72
  73 #define CHECK_STACK_TYPE(s, t)                                       \
  74     if ((s).type != (t))                                             \
  75         goto throw_stack_type_error;
  76
  77 /* XXX inefficient */
  78 #define CHECK_LOCAL_TYPE(index, t)                                   \
  79     do {                                                             \
  80         if (state.locals[(index)].type != (t))                       \
  81             goto throw_local_type_error;                             \
  82         if (STATE->topjsr)                                           \
  83             STATE->topjsr->usedlocals[(index)] = 1;                  \
  84         if (STATE->topjsr && IS_2_WORD_TYPE(t))                      \
  85             STATE->topjsr->usedlocals[(index) + 1] = 1;              \
  86     } while(0)
  87
  88 /* XXX inefficient */
  89 #define STORE_LOCAL(t, index)                                        \
  90     do {                                                             \
  91         state.locals[(index)].type = (t);                            \
  92         if ((index) && IS_2_WORD_TYPE(state.locals[(index)-1].type)) \
  93             state.locals[(index-1)].type = TYPE_VOID;                \
  94         if (STATE->topjsr)                                           \
  95             STATE->topjsr->usedlocals[(index)] = 1;                  \
  96     } while (0)
  97
  98 /* XXX inefficient */
  99 #define STORE_LOCAL_2_WORD(t, index)                                 \
 100     do {                                                             \
 101         STORE_LOCAL(t, index);                                       \
 102         state.locals[(index)+1].type = TYPE_VOID;                    \
 103         if (STATE->topjsr)                                           \
 104             STATE->topjsr->usedlocals[(index)] = 1;                  \
 105     } while (0)
 106
 107 #define VERIFY_ERROR(msg)                                            \
 108     do {                                                             \
 109         LOG1("VerifyError: %s", msg);                                \
 110         exceptions_throw_verifyerror(STATE->m, msg);                 \
 111         return false;                                                \
 112     } while (0)
 113
 114 #define IS_CAT1(slot)                                                \
 115     ((slot).type != TYPE_VOID && !IS_2_WORD_TYPE((slot).type))
 116
 117 #define IS_CAT2(slot)                                                \
 118     ((slot).type != TYPE_VOID && IS_2_WORD_TYPE((slot).type))
 119
 120 #define CHECK_CAT1(slot)                                             \
 121     do {                                                             \
 122         if (!IS_CAT1(slot))                                          \
 123             goto throw_stack_category_error;                         \
 124     } while (0)
 125
 126 #define CHECK_CAT2(slot)                                             \
 127     do {                                                             \
 128         if (!IS_CAT2(slot))                                          \
 129             goto throw_stack_category_error;                         \
 130     } while (0)
 131
 132 #define COPY_SLOT(s, d)                                              \
 133     do { (d) = (s); } while (0)
 134
 135 #define REACH_BLOCK(target)                                          \
 136     do {                                                             \
 137         if (!typecheck_stackbased_reach(STATE, (target), stack,      \
 138                     (stack - stackfloor) + 1))                       \
 139             return false;                                            \
 140     } while (0)
 141
 142 #define REACH(target)                                                \
 143     do {                                                             \
 144         REACH_BLOCK((target).block);                                 \
 145     } while (0)
 146
 147 #undef TYPECHECK_INT
 148 #undef TYPECHECK_LNG
 149 #undef TYPECHECK_FLT
 150 #undef TYPECHECK_DBL
 151 #undef TYPECHECK_ADR
 152
 153 /* XXX should reuse typevector code */
 154 static typecheck_result typecheck_stackbased_merge_locals(methodinfo *m,
 155                                                                                                                   typedescriptor_t *dst,
 156                                                                                                                   typedescriptor_t *y,
 157                                                                                                                   int size)
 158 {
 159         bool changed = false;
 160         typecheck_result r;
 161
 162         typedescriptor_t *a = dst;
 163         typedescriptor_t *b = y;
 164         while (size--) {
 165                 if (a->type != TYPE_VOID && a->type != b->type) {
 166                         a->type = TYPE_VOID;
 167                         changed = true;
 168                 }
 169                 else if (a->type == TYPE_ADR) {
 170                         if (TYPEINFO_IS_PRIMITIVE(a->typeinfo)) {
 171                                 /* 'a' is a returnAddress */
 172                                 if (!TYPEINFO_IS_PRIMITIVE(b->typeinfo)
 173                                         || (TYPEINFO_RETURNADDRESS(a->typeinfo)
 174                                                 != TYPEINFO_RETURNADDRESS(b->typeinfo)))
 175                                 {
 176                                         a->type = TYPE_VOID;
 177                                         changed = true;
 178                                 }
 179                         }
 180                         else {
 181                                 /* 'a' is a reference */
 182                                 if (TYPEINFO_IS_PRIMITIVE(b->typeinfo)) {
 183                                         a->type = TYPE_VOID;
 184                                         changed = true;
 185                                 }
 186                                 else {
 187                                         /* two reference types are merged. There cannot be */
 188                                         /* a merge error. In the worst case we get j.l.O.  */
 189                                         r = typeinfo_merge(m,&(a->typeinfo),&(b->typeinfo));
 190                                         if (r == typecheck_FAIL)
 191                                                 return r;
 192                                         changed |= r;
 193                                 }
 194                         }
 195                 }
 196                 a++;
 197                 b++;
 198         }
 199         return changed;
 200 }
 201
 202 static typecheck_result typecheck_stackbased_merge(verifier_state *state,
 203                                                                                                    basicblock *destblock,
 204                                                                                                    typedescriptor_t *stack,
 205                                                                                                    s4 stackdepth)
 206 {
 207         s4 i;
 208         s4 destidx;
 209         typedescriptor_t *stackfloor;
 210         typedescriptor_t *sp;
 211         typedescriptor_t *dp;
 212         typecheck_result r;
 213         bool changed = false;
 214
 215         destidx = destblock->nr;
 216
 217         if (stackdepth != state->indepth[destidx]) {
 218                 exceptions_throw_verifyerror(state->m, "Stack depth mismatch");
 219                 return typecheck_FAIL;
 220         }
 221
 222         stackfloor = stack - (stackdepth - 1);
 223
 224         sp = stackfloor;
 225         dp = state->startstack + (destidx * state->m->maxstack);
 226
 227         for (i=0; i<stackdepth; ++i, ++sp, ++dp) {
 228                 if (sp->type != dp->type) {
 229                         exceptions_throw_verifyerror(state->m, "Mismatched stack types");
 230                         return typecheck_FAIL;
 231                 }
 232                 if (dp->type == TYPE_ADR) {
 233                         if (TYPEINFO_IS_PRIMITIVE(dp->typeinfo)) {
 234                                 /* dp has returnAddress type */
 235                                 if (TYPEINFO_IS_PRIMITIVE(sp->typeinfo)) {
 236                                         if (TYPEINFO_RETURNADDRESS(dp->typeinfo) != TYPEINFO_RETURNADDRESS(sp->typeinfo)) {
 237                                                 exceptions_throw_verifyerror(state->m, "Mismatched stack types");
 238                                                 return typecheck_FAIL;
 239                                         }
 240                                 }
 241                                 else {
 242                                         exceptions_throw_verifyerror(state->m,"Merging returnAddress with reference");
 243                                         return typecheck_FAIL;
 244                                 }
 245                         }
 246                         else {
 247                                 /* dp has reference type */
 248                                 if (TYPEINFO_IS_PRIMITIVE(sp->typeinfo)) {
 249                                         exceptions_throw_verifyerror(state->m,"Merging reference with returnAddress");
 250                                         return typecheck_FAIL;
 251                                 }
 252                                 r = typeinfo_merge(state->m,&(dp->typeinfo),&(sp->typeinfo));
 253                                 if (r == typecheck_FAIL)
 254                                         return r;
 255                                 changed |= r;
 256                         }
 257                 }
 258         }
 259
 260         dp = state->startlocals + (destidx * state->numlocals);
 261         r = typecheck_stackbased_merge_locals(state->m, dp, state->locals, state->numlocals);
 262         if (r == typecheck_FAIL)
 263                 return r;
 264         changed |= r;
 265
 266         return changed;
 267 }
 268
 269 static bool typecheck_stackbased_reach(verifier_state *state,
 270                                                                            basicblock *destblock,
 271                                                                            typedescriptor_t *stack,
 272                                                                            s4 stackdepth)
 273 {
 274         bool changed = false;
 275         typecheck_result r;
 276
 277         assert(destblock);
 278
 279         if (destblock->flags == BBTYPECHECK_UNDEF) {
 280                 /* The destblock has never been reached before */
 281
 282                 TYPECHECK_COUNT(stat_copied);
 283                 LOG1("block L%03d reached first time",destblock->nr); LOGSTR("\t");
 284                 DOLOG( typecheck_stackbased_show_state(state, stack, stack - (stackdepth - 1), false); );
 285
 286                 state->indepth[destblock->nr] = stackdepth;
 287
 288                 MCOPY(state->startstack + (destblock->nr * state->m->maxstack),
 289                           stack - (stackdepth - 1),
 290                           typedescriptor_t,
 291                           stackdepth);
 292
 293                 MCOPY(state->startlocals + (destblock->nr * state->numlocals),
 294                           state->locals,
 295                           typedescriptor_t,
 296                           state->numlocals);
 297
 298                 changed = true;
 299         }
 300         else {
 301                 /* The destblock has already been reached before */
 302
 303                 TYPECHECK_COUNT(stat_merged);
 304                 LOG1("block L%03d reached before", destblock->nr); LOGSTR("\t");
 305                 DOLOG( typecheck_stackbased_show_state(state, stack, stack - (stackdepth - 1), false); );
 306
 307                 r = typecheck_stackbased_merge(state, destblock, stack, stackdepth);
 308                 if (r == typecheck_FAIL)
 309                         return false;
 310                 changed = r;
 311
 312                 TYPECHECK_COUNTIF(changed,stat_merging_changed);
 313         }
 314
 315         if (changed) {
 316                 LOG("\tchanged!");
 317                 destblock->flags = BBTYPECHECK_REACHED;
 318                 /* XXX is this check ok? */
 319                 if (destblock->nr <= state->bptr->nr) {
 320                         LOG("\tREPEAT!");
 321                         state->repeat = true;
 322                 }
 323         }
 324         return true;
 325 }
 326
 327
 328 /* typecheck_stackbased_verify_fieldaccess *************************************
 329
 330    Verify an ICMD_{GET,PUT}{STATIC,FIELD}
 331
 332    IN:
 333        state............the current state of the verifier
 334            instance.........the instance slot, or NULL
 335            value............the value slot, or NULL
 336            stack............stack after popping the arguments
 337
 338    RETURN VALUE:
 339        stack pointer....successful verification,
 340            NULL.............an exception has been thrown.
 341
 342 *******************************************************************************/
 343
 344 static typedescriptor_t *typecheck_stackbased_verify_fieldaccess(
 345                 verifier_state *state,
 346                 typedescriptor_t *instance,
 347                 typedescriptor_t *value,
 348                 typedescriptor_t *stack)
 349 {
 350         jitdata *jd;
 351
 352         jd = state->jd;
 353
 354 #define TYPECHECK_STACKBASED
 355 #define EXCEPTION  do { return NULL; } while (0)
 356 #define STATE  state
 357 #include <typecheck-fields.inc>
 358 #undef  EXCEPTION
 359 #undef  STATE
 360 #undef  TYPECHECK_STACKBASED
 361
 362         return stack;
 363
 364 throw_stack_overflow:
 365         LOG("STACK OVERFLOW!");
 366         exceptions_throw_verifyerror(state->m, "Stack size too large");
 367         return NULL;
 368 }
 369
 370 static bool typecheck_stackbased_verify_invocation(verifier_state *state,
 371                                                                                                    typedescriptor_t *stack,
 372                                                                                                    typedescriptor_t *stackfloor)
 373 {
 374         s4 paramslots;
 375         methoddesc *md;
 376         typedescriptor_t *dv;
 377
 378         /* check stack depth */
 379
 380         /* XXX parse params */
 381
 382         INSTRUCTION_GET_METHODDESC(state->iptr, md);
 383
 384         paramslots = md->paramslots;
 385
 386         if ((stack - stackfloor) + 1 < paramslots) {
 387                 exceptions_throw_verifyerror(state->m,
 388                                 "Trying to pop operand of an empty stack");
 389                 return false;
 390         }
 391
 392         dv = stack - (paramslots - 1);
 393
 394 #define TYPECHECK_STACKBASED
 395 #define OP1   dv
 396 #include <typecheck-invoke.inc>
 397 #undef  OP1
 398 #undef  TYPECHECK_STACKBASED
 399
 400         return true;
 401 }
 402
 403 static bool typecheck_stackbased_verify_builtin(verifier_state *state,
 404                                                                                                 typedescriptor_t *stack,
 405                                                                                                 typedescriptor_t *stackfloor)
 406 {
 407         s4 paramslots;
 408         typedescriptor_t *dv;
 409
 410         /* check stack depth */
 411
 412         /* XXX parse params */
 413
 414         paramslots = state->iptr->sx.s23.s3.bte->md->paramslots;
 415
 416         if ((stack - stackfloor) + 1 < paramslots) {
 417                 exceptions_throw_verifyerror(state->m,
 418                                 "Trying to pop operand of an empty stack");
 419                 return false;
 420         }
 421
 422         dv = stack - (paramslots - 1);
 423
 424 #define TYPECHECK_STACKBASED
 425 #define OP1   dv
 426 #define TYPECHECK_INT(s)  CHECK_STACK_TYPE(*(s), TYPE_INT)
 427 #define TYPECHECK_ADR(s)  CHECK_STACK_TYPE(*(s), TYPE_ADR)
 428 #define TYPECHECK_LNG(s)  CHECK_STACK_TYPE(*(s), TYPE_LNG)
 429 #define TYPECHECK_FLT(s)  CHECK_STACK_TYPE(*(s), TYPE_FLT)
 430 #define TYPECHECK_DBL(s)  CHECK_STACK_TYPE(*(s), TYPE_DBL)
 431 #include <typecheck-builtins.inc>
 432 #undef  OP1
 433 #undef  TYPECHECK_STACKBASED
 434
 435         return true;
 436
 437 throw_stack_type_error:
 438         exceptions_throw_verifyerror(state->m, "Wrong type on stack"); /* XXX */
 439         return false;
 440 }
 441
 442 static bool typecheck_stackbased_multianewarray(verifier_state *state,
 443                                                                                                 typedescriptor_t *stack,
 444                                                                                                 typedescriptor_t *stackfloor)
 445 {
 446         /* XXX recombine with verify_multianewarray */
 447
 448         classinfo *arrayclass;
 449         arraydescriptor *desc;
 450         s4 i;
 451         typedescriptor_t *sp;
 452         typedescriptor_t *dst;
 453
 454         /* destination slot */
 455
 456         i = state->iptr->s1.argcount;
 457
 458         dst = stack - (i-1);
 459
 460         /* check the array lengths on the stack */
 461
 462         if ((stack - stackfloor) + 1 < i) {
 463                 exceptions_throw_verifyerror(state->m,
 464                                 "Trying to pop operand of an empty stack");
 465                 return false;
 466         }
 467
 468         if (i < 1)
 469                 TYPECHECK_VERIFYERROR_bool("Illegal dimension argument");
 470
 471         for (sp = dst; sp <= stack; ++sp) {
 472                 if (sp->type != TYPE_INT) {
 473                         exceptions_throw_verifyerror_for_stack(state->m, TYPE_INT);
 474                         return false;
 475                 }
 476         }
 477
 478         /* check array descriptor */
 479
 480         if (INSTRUCTION_IS_RESOLVED(state->iptr)) {
 481                 /* the array class reference has already been resolved */
 482                 arrayclass = state->iptr->sx.s23.s3.c.cls;
 483                 if (!arrayclass)
 484                         TYPECHECK_VERIFYERROR_bool("MULTIANEWARRAY with unlinked class");
 485                 if ((desc = arrayclass->vftbl->arraydesc) == NULL)
 486                         TYPECHECK_VERIFYERROR_bool("MULTIANEWARRAY with non-array class");
 487                 if (desc->dimension < state->iptr->s1.argcount)
 488                         TYPECHECK_VERIFYERROR_bool("MULTIANEWARRAY dimension to high");
 489
 490                 /* set the array type of the result */
 491                 typeinfo_init_classinfo(&(dst->typeinfo), arrayclass);
 492         }
 493         else {
 494                 const char *p;
 495                 constant_classref *cr;
 496
 497                 /* the array class reference is still unresolved */
 498                 /* check that the reference indicates an array class of correct dimension */
 499                 cr = state->iptr->sx.s23.s3.c.ref;
 500                 i = 0;
 501                 p = cr->name->text;
 502                 while (p[i] == '[')
 503                         i++;
 504                 /* { the dimension of the array class == i } */
 505                 if (i < 1)
 506                         TYPECHECK_VERIFYERROR_bool("MULTIANEWARRAY with non-array class");
 507                 if (i < state->iptr->s1.argcount)
 508                         TYPECHECK_VERIFYERROR_bool("MULTIANEWARRAY dimension to high");
 509
 510                 /* set the array type of the result */
 511                 if (!typeinfo_init_class(&(dst->typeinfo),CLASSREF_OR_CLASSINFO(cr)))
 512                         return false;
 513         }
 514
 515         /* everything ok */
 516         return true;
 517
 518 }
 519
 520 static void typecheck_stackbased_add_jsr_caller(typecheck_jsr_t *jsr,
 521                                                                                                 basicblock *bptr)
 522 {
 523         typecheck_jsr_caller_t *jc;
 524
 525         for (jc = jsr->callers; jc; jc = jc->next)
 526                 if (jc->callblock == bptr)
 527                         return;
 528
 529         jc = DNEW(typecheck_jsr_caller_t);
 530         jc->next = jsr->callers;
 531         jc->callblock = bptr;
 532         jsr->callers = jc;
 533 }
 534
 535 static typedescriptor_t *typecheck_stackbased_jsr(verifier_state *state,
 536                                                                                                 typedescriptor_t *stack,
 537                                                                                                 typedescriptor_t *stackfloor)
 538 {
 539         typecheck_jsr_t *jsr;
 540         basicblock *tbptr;
 541         jitdata *jd;
 542         s4 i;
 543
 544         jd = state->jd;
 545
 546         tbptr = state->iptr->sx.s23.s3.jsrtarget.block;
 547         jsr = state->jsrinfos[tbptr->nr];
 548
 549         if (jsr && tbptr->flags == BBFINISHED) {
 550
 551                 LOG1("another JSR to analysed subroutine L%03d", tbptr->nr);
 552                 if (jsr->active) {
 553                         exceptions_throw_verifyerror(state->m, "Recursive JSR");
 554                         return NULL;
 555                 }
 556
 557                 assert(jsr->callers);
 558                 assert(jsr->callers->callblock);
 559
 560                 /* copy the stack of the RET edge */
 561
 562                 MCOPY(stackfloor, jsr->retstack, typedescriptor_t, jsr->retdepth);
 563                 stack = stackfloor + (jsr->retdepth - 1);
 564
 565                 /* copy variables that were used in the subroutine from the RET edge */
 566
 567                 for (i=0; i<state->numlocals; ++i)
 568                         if (jsr->usedlocals[i])
 569                                 state->locals[i] = jsr->retlocals[i];
 570
 571                 /* reach the following block */
 572
 573                 if (!typecheck_stackbased_reach(state, state->bptr->next, stack,
 574                                         (stack - stackfloor) + 1))
 575                         return NULL;
 576         }
 577         else {
 578                 if (!jsr) {
 579                         LOG1("first JSR to block L%03d", tbptr->nr);
 580
 581                         jsr = DNEW(typecheck_jsr_t);
 582                         state->jsrinfos[tbptr->nr] = jsr;
 583                         jsr->callers = NULL;
 584                         jsr->blockflags = DMNEW(char, state->basicblockcount);
 585                         jsr->retblock = NULL;
 586                         jsr->start = tbptr;
 587                         jsr->usedlocals = DMNEW(char, state->numlocals);
 588                         MZERO(jsr->usedlocals, char, state->numlocals);
 589                         jsr->retlocals = DMNEW(typedescriptor_t, state->numlocals);
 590                         jsr->retstack = DMNEW(typedescriptor_t, state->m->maxstack);
 591                         jsr->retdepth = 0;
 592                 }
 593                 else {
 594                         LOG1("re-analysing JSR to block L%03d", tbptr->nr);
 595                 }
 596
 597                 jsr->active = true;
 598                 jsr->next = state->topjsr;
 599                 state->topjsr = jsr;
 600
 601                 assert(state->iptr->sx.s23.s3.jsrtarget.block->flags == BBTYPECHECK_REACHED);
 602
 603                 tbptr->flags = BBFINISHED;
 604
 605                 for (tbptr = state->basicblocks; tbptr != NULL; tbptr = tbptr->next) {
 606                         jsr->blockflags[tbptr->nr] = tbptr->flags;
 607
 608                         if (tbptr->flags == BBTYPECHECK_REACHED)
 609                                 tbptr->flags = BBFINISHED;
 610                 }
 611
 612                 state->iptr->sx.s23.s3.jsrtarget.block->flags = BBTYPECHECK_REACHED;
 613         }
 614
 615         /* register this block as a caller, if not already done */
 616
 617         typecheck_stackbased_add_jsr_caller(jsr, state->bptr);
 618
 619         return stack;
 620 }
 621
 622 static bool typecheck_stackbased_ret(verifier_state *state,
 623                                                                          typedescriptor_t *stack,
 624                                                                          typedescriptor_t *stackfloor)
 625 {
 626         basicblock *tbptr;
 627         typecheck_jsr_caller_t *jsrcaller;
 628         typecheck_jsr_t *jsr;
 629         s4 i;
 630
 631         /* get the subroutine we are RETurning from */
 632
 633         tbptr = TYPEINFO_RETURNADDRESS(state->locals[state->iptr->s1.varindex].typeinfo);
 634         if (tbptr == NULL) {
 635                 exceptions_throw_verifyerror(state->m, "Illegal RET");
 636                 return false;
 637         }
 638
 639         LOG1("RET from subroutine L%03d", tbptr->nr);
 640         jsr = state->jsrinfos[tbptr->nr];
 641         assert(jsr);
 642
 643         /* check against recursion */
 644
 645         if (!jsr->active) {
 646                 exceptions_throw_verifyerror(state->m, "RET outside of local subroutine");
 647                 return false;
 648         }
 649
 650         /* check against multiple RETs for one subroutine */
 651
 652         if (jsr->retblock && jsr->retblock != state->bptr) {
 653                 exceptions_throw_verifyerror(state->m, "Multiple RETs from local subroutine");
 654                 return false;
 655         }
 656
 657         /* store data-flow of the RET edge */
 658
 659         jsr->retblock = state->bptr;
 660         jsr->retdepth = (stack - stackfloor) + 1;
 661         MCOPY(jsr->retstack, stackfloor, typedescriptor_t, jsr->retdepth);
 662         MCOPY(jsr->retlocals, state->locals, typedescriptor_t, state->numlocals);
 663
 664         /* invalidate the returnAddress used by this RET */
 665         /* XXX should we also invalidate the returnAddresses of JSRs that are skipped by this RET? */
 666
 667         for (i=0; i<state->numlocals; ++i) {
 668                 typedescriptor_t *lc = &(jsr->retlocals[i]);
 669                 if (TYPE_IS_RETURNADDRESS(lc->type, lc->typeinfo))
 670                         if (TYPEINFO_RETURNADDRESS(lc->typeinfo) == tbptr) {
 671                                 LOG1("invalidating returnAddress in local %d", i);
 672                                 TYPEINFO_INIT_RETURNADDRESS(lc->typeinfo, NULL);
 673                         }
 674         }
 675
 676         /* touch all callers of the subroutine, so they are analysed again */
 677
 678         for (jsrcaller = jsr->callers; jsrcaller != NULL; jsrcaller = jsrcaller->next) {
 679                 tbptr = jsrcaller->callblock;
 680                 LOG1("touching caller L%03d from RET", tbptr->nr);
 681                 assert(jsr->blockflags[tbptr->nr] >= BBFINISHED);
 682                 jsr->blockflags[tbptr->nr] = BBTYPECHECK_REACHED; /* XXX repeat? */
 683         }
 684
 685         return true;
 686 }
 687
 688 bool typecheck_stackbased(jitdata *jd)
 689 {
 690         register verifier_slot_t *stack;
 691         verifier_slot_t *stackfloor;
 692         s4 len;
 693         methoddesc *md;
 694         bool maythrow;
 695         bool superblockend;
 696         verifier_slot_t temp;
 697         branch_target_t *table;
 698         lookup_target_t *lookup;
 699         s4 i;
 700         typecheck_result r;
 701         verifier_slot_t *dst;
 702         verifier_state state;
 703         basicblock *tbptr;
 704         exception_entry *ex;
 705         typedescriptor_t exstack;
 706         s4 skip = 0;
 707
 708         DOLOG( show_method(jd, SHOW_PARSE); );
 709
 710         /* initialize verifier state */
 711
 712         state.jd = jd;
 713         state.m = jd->m;
 714         state.cd = jd->cd;
 715         state.basicblocks = jd->basicblocks;
 716         state.basicblockcount = jd->basicblockcount;
 717         state.topjsr = NULL;
 718 #   define STATE (&state)
 719
 720         /* check that the basicblock numbers are valid */
 721
 722 #if !defined(NDEBUG)
 723         jit_check_basicblock_numbers(jd);
 724 #endif
 725
 726         /* check if this method is an instance initializer method */
 727
 728     state.initmethod = (state.m->name == utf_init);
 729
 730         /* allocate parameter descriptors if necessary */
 731
 732         if (!state.m->parseddesc->params)
 733                 if (!descriptor_params_from_paramtypes(state.m->parseddesc,state.m->flags))
 734                         return false;
 735
 736         /* allocate the stack buffers */
 737
 738         stackfloor = DMNEW(verifier_slot_t, state.m->maxstack + 1);
 739         state.stackceiling = stackfloor + state.m->maxstack;
 740         stack = stackfloor - 1;
 741         state.indepth = DMNEW(s4, state.basicblockcount);
 742         state.startstack = DMNEW(verifier_slot_t, state.m->maxstack * state.basicblockcount);
 743
 744         /* allocate the local variables buffers */
 745
 746         state.numlocals = state.m->maxlocals;
 747         state.validlocals = state.m->maxlocals;
 748     if (state.initmethod)
 749                 state.numlocals++; /* extra marker variable */
 750
 751         state.locals = DMNEW(verifier_slot_t, state.numlocals);
 752         state.startlocals = DMNEW(verifier_slot_t, state.numlocals * state.basicblockcount);
 753
 754     /* allocate the buffer of active exception handlers */
 755
 756     state.handlers = DMNEW(exception_entry*, state.jd->exceptiontablelength + 1);
 757
 758     /* initialize instack of exception handlers */
 759
 760         exstack.type = TYPE_ADR;
 761         typeinfo_init_classinfo(&(exstack.typeinfo),
 762                                                         class_java_lang_Throwable); /* changed later */
 763
 764     LOG("Exception handler stacks set.\n");
 765
 766         /* initialize jsr info buffer */
 767
 768         state.jsrinfos = DMNEW(typecheck_jsr_t *, state.basicblockcount);
 769         MZERO(state.jsrinfos, typecheck_jsr_t *, state.basicblockcount);
 770
 771         /* initialize stack of first block */
 772
 773         state.indepth[0] = 0;
 774
 775         /* initialize locals of first block */
 776
 777     /* if this is an instance method initialize the "this" ref type */
 778
 779     if (!(state.m->flags & ACC_STATIC)) {
 780                 if (state.validlocals < 1)
 781                         VERIFY_ERROR("Not enough local variables for method arguments");
 782                 dst = state.startlocals;
 783                 dst->type = TYPE_ADR;
 784                 if (state.initmethod)
 785                         TYPEINFO_INIT_NEWOBJECT(dst->typeinfo, NULL);
 786                 else
 787                         typeinfo_init_classinfo(&(dst->typeinfo), state.m->clazz);
 788
 789                 skip = 1;
 790     }
 791
 792     LOG("'this' argument set.\n");
 793
 794         len = typedescriptors_init_from_methoddesc(state.startlocals + skip,
 795                         state.m->parseddesc,
 796                         state.validlocals, true, skip, &state.returntype);
 797         if (len < 0)
 798                 return false;
 799
 800         /* set remaining locals to void */
 801
 802         for (i = skip + len; i<state.numlocals; ++i)
 803                 state.startlocals[i].type = TYPE_VOID;
 804
 805         /* initialize block flags */
 806
 807         typecheck_init_flags(&state, BBUNDEF);
 808
 809         /* iterate until fixpoint reached */
 810
 811         do {
 812
 813                 state.repeat = false;
 814
 815                 /* iterate over the basic blocks */
 816
 817                 for (state.bptr = state.basicblocks; state.bptr != NULL; state.bptr = state.bptr->next) {
 818
 819                         if (state.bptr->flags != BBTYPECHECK_REACHED)
 820                                 continue;
 821
 822                         DOLOG( show_basicblock(jd, state.bptr, SHOW_PARSE); );
 823
 824                         /* mark this block as analysed */
 825
 826                         state.bptr->flags = BBFINISHED;
 827
 828                         /* determine the active exception handlers for this block */
 829                         /* XXX could use a faster algorithm with sorted lists or  */
 830                         /* something?                                             */
 831                         /* XXX reuse code from variables based verifer? */
 832                         len = 0;
 833                         for (ex = STATE->jd->exceptiontable; ex ; ex = ex->down) {
 834                                 if ((ex->start->nr <= STATE->bptr->nr) && (ex->end->nr > STATE->bptr->nr)) {
 835                                         LOG1("\tactive handler L%03d", ex->handler->nr);
 836                                         STATE->handlers[len++] = ex;
 837                                 }
 838                         }
 839                         STATE->handlers[len] = NULL;
 840
 841                         /* initialize the locals */
 842
 843                         MCOPY(state.locals,
 844                                   state.startlocals + (state.bptr->nr * state.numlocals),
 845                                   verifier_slot_t, state.numlocals);
 846
 847                         /* initialize the stack */
 848
 849                         len = state.indepth[state.bptr->nr];
 850
 851                         MCOPY(stackfloor,
 852                                   state.startstack + (state.bptr->nr * state.m->maxstack),
 853                                   verifier_slot_t, len);
 854
 855                         stack = stackfloor + (len - 1);
 856
 857                         /* iterate over the instructions in this block */
 858
 859                         state.iptr = state.bptr->iinstr;
 860                         len = state.bptr->icount;
 861
 862                         superblockend = false;
 863
 864                         for (; len--; state.iptr++) {
 865
 866                                 maythrow = false;
 867
 868                                 LOGNL;
 869                                 DOLOG( typecheck_stackbased_show_state(&state, stack, stackfloor, true); );
 870
 871                                 switch (state.iptr->opc) {
 872 #define TYPECHECK_STACKBASED 1
 873 #define STATE (&state)
 874 #define IPTR state.iptr
 875 #define BPTR state.bptr
 876 #define METHOD state.m
 877 #define LOCAL_SLOT(index)  (state.locals + (index))
 878 #define EXCEPTION                                                    \
 879     do {                                                             \
 880         LOG("EXCEPTION THROWN!\n");                                  \
 881         return false;                                                \
 882     } while (0)
 883
 884 #include <typecheck-stackbased-gen.inc>
 885 #undef  TYPECHECK_STACKBASED
 886                                 }
 887
 888                                 /* reach exception handlers for this instruction */
 889
 890                                 if (maythrow) {
 891                                         TYPECHECK_COUNT(stat_ins_maythrow);
 892                                         TYPECHECK_MARK(STATE->stat_maythrow);
 893                                         LOG("\treaching exception handlers");
 894                                         i = 0;
 895                                         while (STATE->handlers[i]) {
 896                                                 TYPECHECK_COUNT(stat_handlers_reached);
 897                                                 if (STATE->handlers[i]->catchtype.any)
 898                                                         exstack.typeinfo.typeclass = STATE->handlers[i]->catchtype;
 899                                                 else
 900                                                         exstack.typeinfo.typeclass.cls = class_java_lang_Throwable;
 901                                                 if (!typecheck_stackbased_reach(
 902                                                                 STATE,
 903                                                                 STATE->handlers[i]->handler,
 904                                                                 &exstack, 1))
 905                                                         EXCEPTION;
 906                                                 i++;
 907                                         }
 908                                 }
 909                         }
 910
 911                         /* propagate types to the following block */
 912
 913                         if (!superblockend) {
 914                                 if (!typecheck_stackbased_reach(&state, state.bptr->next,
 915                                                                                                 stack, stack - stackfloor + 1))
 916                                         EXCEPTION;
 917                         }
 918                 } /* end loop over blocks */
 919
 920                 while (!state.repeat && state.topjsr) {
 921                         LOG1("done analysing subroutine L%03d", state.topjsr->start->nr);
 922
 923                         /* propagate down used locals */
 924
 925                         if (state.topjsr->next) {
 926                                 for (i=0; i<state.numlocals; ++i)
 927                                         state.topjsr->next->usedlocals[i] |= state.topjsr->usedlocals[i];
 928                         }
 929
 930                         /* restore REACHED flags */
 931
 932                         for (tbptr = state.basicblocks; tbptr != NULL; tbptr = tbptr->next) {
 933                                 assert(tbptr->flags != BBTYPECHECK_REACHED);
 934                                 if (state.topjsr->blockflags[tbptr->nr] == BBTYPECHECK_REACHED) {
 935                                         tbptr->flags = BBTYPECHECK_REACHED;
 936                                         state.repeat = true;
 937                                 }
 938                         }
 939
 940                         /* dactivate the subroutine */
 941
 942                         state.topjsr->active = false;
 943                         state.topjsr = state.topjsr->next;
 944                 }
 945         } while (state.repeat);
 946
 947         /* reset block flags */
 948
 949         typecheck_reset_flags(&state);
 950
 951         LOG("typecheck_stackbased successful");
 952
 953         return true;
 954
 955 throw_stack_underflow:
 956         LOG("STACK UNDERFLOW!");
 957         exceptions_throw_verifyerror(state.m, "Unable to pop operand off an empty stack");
 958         return false;
 959
 960 throw_stack_overflow:
 961         LOG("STACK OVERFLOW!");
 962         exceptions_throw_verifyerror(state.m, "Stack size too large");
 963         return false;
 964
 965 throw_stack_type_error:
 966         LOG("STACK TYPE ERROR!");
 967         exceptions_throw_verifyerror(state.m, "Mismatched stack types");
 968         return false;
 969
 970 throw_local_type_error:
 971         LOG("LOCAL TYPE ERROR!");
 972         exceptions_throw_verifyerror(state.m, "Local variable type mismatch");
 973         return false;
 974
 975 throw_stack_category_error:
 976         LOG("STACK CATEGORY ERROR!");
 977         exceptions_throw_verifyerror(state.m, "Attempt to split long or double on the stack");
 978         return false;
 979 }
 980
 981
 982 #if defined(TYPECHECK_VERBOSE)
 983 static void typecheck_stackbased_show_state(verifier_state *state,
 984                                                                                         typedescriptor_t *stack,
 985                                                                                         typedescriptor_t *stackfloor,
 986                                                                                         bool showins)
 987 {
 988         typedescriptor_t *sp;
 989         s4 i;
 990
 991         LOGSTR1("stackdepth %d stack [", (stack - stackfloor) + 1);
 992         for (sp=stackfloor; sp <= stack; sp++) {
 993                 LOGSTR(" ");
 994                 DOLOG( typedescriptor_print(stdout, sp); );
 995         }
 996         LOGSTR(" ] locals [");
 997         for (i=0; i<state->numlocals; ++i) {
 998                 LOGSTR(" ");
 999                 DOLOG( typedescriptor_print(stdout, state->locals + i); );
1000         }
1001         LOGSTR(" ]");
1002         LOGNL;
1003         if (showins && state->iptr < (state->bptr->iinstr + state->bptr->icount)) {
1004                 LOGSTR("\t");
1005                 DOLOG( show_icmd(state->jd, state->iptr, false, SHOW_PARSE); );
1006                 LOGNL;
1007         }
1008 }
1009 #endif
1010
1011 #endif /* defined(ENABLE_VERIFIER) */
1012
1013
1014 /*
1015  * These are local overrides for various environment variables in Emacs.
1016  * Please do not remove this and leave it at the end of the file, where
1017  * Emacs will automagically detect them.
1018  * ---------------------------------------------------------------------
1019  * Local variables:
1020  * mode: c
1021  * indent-tabs-mode: t
1022  * c-basic-offset: 4
1023  * tab-width: 4
1024  * End:
1025  * vim:noexpandtab:sw=4:ts=4:
1026  */
1027