1 /* Handle verification of bytecoded methods for the GNU compiler for
3 Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002 Free Software Foundation, Inc.
5 This file is part of GNU CC.
7 GNU CC is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 2, or (at your option)
12 GNU CC is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with GNU CC; see the file COPYING. If not, write to
19 the Free Software Foundation, 59 Temple Place - Suite 330,
20 Boston, MA 02111-1307, USA.
22 Java and all Java-based marks are trademarks or registered trademarks
23 of Sun Microsystems, Inc. in the United States and other countries.
24 The Free Software Foundation is independent of Sun Microsystems, Inc. */
29 #include "java-tree.h"
31 #include "java-opcodes.h"
33 #include "java-except.h"
36 static void push_pending_label PARAMS ((tree));
37 static tree merge_types PARAMS ((tree, tree));
38 static const char *check_pending_block PARAMS ((tree));
39 static void type_stack_dup PARAMS ((int, int));
40 static int start_pc_cmp PARAMS ((const PTR, const PTR));
41 static char *pop_argument_types PARAMS ((tree));
43 extern int stack_pointer;
45 /* During verification, start of the current subroutine (jsr target). */
48 /* A list of pending blocks, chained using LABEL_PENDING_CHAIN.
49 A pending block is one that has LABEL_CHANGED set, which means
50 it requires (re-) verification. */
53 /* Append TARGET_LABEL to the pending_block stack unless already in it. */
56 push_pending_label (target_label)
59 if (! LABEL_CHANGED (target_label))
61 LABEL_PENDING_CHAIN (target_label) = pending_blocks;
62 pending_blocks = target_label;
63 LABEL_CHANGED (target_label) = 1;
67 /* Note that TARGET_LABEL is a possible successor instruction.
68 Merge the type state etc.
69 Return NULL on success, or an error message on failure. */
72 check_pending_block (target_label)
75 int changed = merge_type_state (target_label);
80 return "types could not be merged";
81 push_pending_label (target_label);
84 if (current_subr == NULL)
86 if (LABEL_IN_SUBR (target_label))
87 return "might transfer control into subroutine";
91 if (LABEL_IN_SUBR (target_label))
93 if (LABEL_SUBR_START (target_label) != current_subr)
94 return "transfer out of subroutine";
96 else if (! LABEL_VERIFIED (target_label))
98 LABEL_IN_SUBR (target_label) = 1;
99 LABEL_SUBR_START (target_label) = current_subr;
102 return "transfer out of subroutine";
107 /* Count the number of nested jsr calls needed to reach LABEL. */
110 subroutine_nesting (tree label)
113 while (label != NULL_TREE && LABEL_IN_SUBR (label))
115 if (! LABEL_IS_SUBR_START(label))
116 label = LABEL_SUBR_START (label);
117 label = LABEL_SUBR_CONTEXT (label);
123 /* Return the "merged" types of TYPE1 and TYPE2.
124 If either is primitive, the other must match (after promotion to int).
125 For reference types, return the common super-class.
126 Return TYPE_UNKNOWN if the types cannot be merged. */
129 merge_types (type1, type2)
134 if (type1 == TYPE_UNKNOWN || type2 == TYPE_UNKNOWN
135 || type1 == TYPE_RETURN_ADDR || type2 == TYPE_RETURN_ADDR)
137 if (TREE_CODE (type1) == POINTER_TYPE && TREE_CODE (type2) == POINTER_TYPE)
141 /* ptr_type_node is only used for a null reference,
142 which is compatible with any reference type. */
143 if (type1 == ptr_type_node || type2 == object_ptr_type_node)
145 if (type2 == ptr_type_node || type1 == object_ptr_type_node)
148 tt1 = TREE_TYPE (type1);
149 tt2 = TREE_TYPE (type2);
151 /* If tt{1,2} haven't been properly loaded, now is a good time
153 if (!TYPE_SIZE (tt1))
156 safe_layout_class (tt1);
159 if (!TYPE_SIZE (tt2))
162 safe_layout_class (tt2);
165 if (TYPE_ARRAY_P (tt1) || TYPE_ARRAY_P (tt2))
167 if (TYPE_ARRAY_P (tt1) == TYPE_ARRAY_P (tt2))
169 tree el_type1 = TYPE_ARRAY_ELEMENT (tt1);
170 tree el_type2 = TYPE_ARRAY_ELEMENT (tt2);
171 tree el_type = NULL_TREE;
172 if (el_type1 == el_type2)
174 else if (TREE_CODE (el_type1) == POINTER_TYPE
175 && TREE_CODE (el_type2) == POINTER_TYPE)
176 el_type = merge_types (el_type1, el_type2);
177 if (el_type != NULL_TREE)
179 HOST_WIDE_INT len1 = java_array_type_length (tt1);
180 HOST_WIDE_INT len2 = java_array_type_length (tt2);
183 else if (el_type1 == el_type2)
185 return promote_type (build_java_array_type (el_type, len1));
188 return object_ptr_type_node;
191 if (CLASS_INTERFACE (TYPE_NAME (tt1)))
193 /* FIXME: should see if two interfaces have a common
195 if (CLASS_INTERFACE (TYPE_NAME (tt2)))
197 /* This is a kludge, but matches what Sun's verifier does.
198 It can be tricked, but is safe as long as type errors
199 (i.e. interface method calls) are caught at run-time. */
200 return object_ptr_type_node;
204 if (can_widen_reference_to (tt2, tt1))
207 return object_ptr_type_node;
210 else if (CLASS_INTERFACE (TYPE_NAME (tt2)))
212 if (can_widen_reference_to (tt1, tt2))
215 return object_ptr_type_node;
221 depth1 = class_depth (type1);
222 depth2 = class_depth (type2);
223 for ( ; depth1 > depth2; depth1--)
224 type1 = TYPE_BINFO_BASETYPE (type1, 0);
225 for ( ; depth2 > depth1; depth2--)
226 type2 = TYPE_BINFO_BASETYPE (type2, 0);
227 while (type1 != type2)
229 type1 = TYPE_BINFO_BASETYPE (type1, 0);
230 type2 = TYPE_BINFO_BASETYPE (type2, 0);
232 return promote_type (type1);
234 if (INTEGRAL_TYPE_P (type1) && INTEGRAL_TYPE_P (type2)
235 && TYPE_PRECISION (type1) <= 32 && TYPE_PRECISION (type2) <= 32)
236 return int_type_node;
240 /* Merge the current type state with that at LABEL.
241 Return -1 the the states are incompatible (i.e. on error),
242 0 if there was no change, and 1 if there was a change. */
245 merge_type_state (label)
248 int nlocals = DECL_MAX_LOCALS (current_function_decl);
249 int cur_length = stack_pointer + nlocals;
250 tree vec = LABEL_TYPE_STATE (label);
252 if (vec == NULL_TREE)
256 vec = make_tree_vec (cur_length);
257 LABEL_TYPE_STATE (label) = vec;
259 while (--cur_length >= 0)
260 TREE_VEC_ELT (vec, cur_length) = type_map [cur_length];
267 if (LABEL_IS_SUBR_START (label) && LABEL_VERIFIED (label)
268 && current_subr != label)
269 return_map = LABEL_RETURN_TYPE_STATE (label);
271 return_map = NULL_TREE;
272 if (TREE_VEC_LENGTH (vec) != cur_length)
276 for (i = 0; i < cur_length; i++)
278 tree old_type = TREE_VEC_ELT (vec, i);
279 tree new_type = merge_types (old_type, type_map [i]);
280 if (TREE_VEC_ELT (vec, i) != new_type)
282 /* If there has been a change, note that since we must re-verify.
283 However, if the label is the start of a subroutine,
284 we don't care about local variables that are neither
285 set nor used in the sub-routine. */
286 if (return_map == NULL_TREE || i >= nlocals
287 || TREE_VEC_ELT (return_map, i) != TYPE_UNUSED
288 || (TYPE_IS_WIDE (new_type)
289 && TREE_VEC_ELT (return_map, i+1) != TYPE_UNUSED))
292 TREE_VEC_ELT (vec, i) = new_type;
293 if (new_type == TYPE_UNKNOWN)
298 else if (TYPE_IS_WIDE (new_type))
305 /* Handle dup-like operations. */
308 type_stack_dup (size, offset)
313 for (index = 0; index < size + offset; index++)
315 type[index] = stack_type_map[stack_pointer - 1];
316 if (type[index] == void_type_node)
319 type[index] = stack_type_map[stack_pointer - 2];
320 if (! TYPE_IS_WIDE (type[index]))
322 if (index == size || index == size + offset)
323 /* Dup operation splits 64-bit number. */
326 pop_type (type[index]);
328 for (index = size; --index >= 0; )
330 if (type[index] != void_type_node)
331 push_type (type[index]);
334 for (index = size + offset; --index >= 0; )
336 if (type[index] != void_type_node)
337 push_type (type[index]);
341 /* This keeps track of a start PC and corresponding initial index. */
348 /* A helper that is used when sorting exception ranges. */
350 start_pc_cmp (xp, yp)
354 const struct pc_index *x = (const struct pc_index *) xp;
355 const struct pc_index *y = (const struct pc_index *) yp;
356 return x->start_pc - y->start_pc;
359 /* This causes the next iteration to ignore the next instruction
360 and look for some other unhandled instruction. */
361 #define INVALIDATE_PC (prevpc = -1, oldpc = PC, PC = INVALID_PC)
362 #define INVALID_PC (-1)
364 #define VERIFICATION_ERROR(MESSAGE) \
365 do { message = MESSAGE; goto verify_error; } while (0)
367 #define VERIFICATION_ERROR_WITH_INDEX(MESSAGE) \
368 do { message = MESSAGE; goto error_with_index; } while (0)
370 /* Recursive helper function to pop argument types during verifiation.
371 ARG_TYPES is the list of formal parameter types.
372 Return NULL on success and a freshly malloc'd error message on failure. */
375 pop_argument_types (arg_types)
378 if (arg_types == end_params_node)
380 if (TREE_CODE (arg_types) == TREE_LIST)
382 char *message = pop_argument_types (TREE_CHAIN (arg_types));
384 pop_type_0 (TREE_VALUE (arg_types), &message);
390 #define POP_TYPE(TYPE, MESSAGE) \
391 do { pmessage = NULL; pop_type_0 (TYPE, &pmessage); \
392 if (pmessage != NULL) goto pop_type_error; \
395 #define POP_TYPE_CONV(TYPE, POPPED_TYPE, MESSAGE) \
396 do { pmessage = NULL; POPPED_TYPE = pop_type_0 (TYPE, &pmessage); \
397 if (pmessage != NULL) goto pop_type_error; \
400 #define PUSH_TYPE(TYPE) \
401 do { if (! push_type_0 (TYPE)) { goto stack_overflow; }} while (0)
403 #define PUSH_PENDING(LABEL) \
404 do { tree tmplab = LABEL; \
405 if ((message = check_pending_block (tmplab)) != NULL) \
406 { oldpc = LABEL_PC (tmplab); goto verify_error; }} while (0)
409 #define CHECK_PC_IN_RANGE(PC) ({if (PC < 0 || PC > length) goto bad_pc; (void)1;})
411 #define CHECK_PC_IN_RANGE(PC) (PC < 0 || PC > length ? (abort (), 0) : 1)
414 #define BCODE byte_ops
416 /* Verify the bytecodes of the current method.
417 Return 1 on success, 0 on failure. */
419 verify_jvm_instructions (jcf, byte_ops, length)
421 const unsigned char *byte_ops;
428 int oldpc = 0; /* PC of start of instruction. */
429 int prevpc = 0; /* If >= 0, PC of previous instruction. */
430 const char *message = 0;
434 register unsigned char *p;
435 struct eh_range *prev_eh_ranges = NULL_EH_RANGE;
436 struct eh_range *eh_ranges;
437 tree return_type = TREE_TYPE (TREE_TYPE (current_function_decl));
438 struct pc_index *starts;
443 pending_blocks = NULL_TREE;
445 /* Handle the exception table. */
446 method_init_exceptions ();
447 JCF_SEEK (jcf, DECL_CODE_OFFSET (current_function_decl) + length);
448 eh_count = JCF_readu2 (jcf);
450 /* We read the exception handlers in order of increasing start PC.
451 To do this we first read and sort the start PCs. */
452 starts = xmalloc (eh_count * sizeof (struct pc_index));
453 for (i = 0; i < eh_count; ++i)
455 starts[i].start_pc = GET_u2 (jcf->read_ptr + 8 * i);
458 qsort (starts, eh_count, sizeof (struct pc_index), start_pc_cmp);
460 for (i = 0; i < eh_count; ++i)
462 int start_pc, end_pc, handler_pc, catch_type;
464 p = jcf->read_ptr + 8 * starts[i].index;
466 start_pc = GET_u2 (p);
467 end_pc = GET_u2 (p+2);
468 handler_pc = GET_u2 (p+4);
469 catch_type = GET_u2 (p+6);
471 if (start_pc < 0 || start_pc >= length
472 || end_pc < 0 || end_pc > length || start_pc >= end_pc
473 || handler_pc < 0 || handler_pc >= length
474 || ! (instruction_bits [start_pc] & BCODE_INSTRUCTION_START)
475 || (end_pc < length &&
476 ! (instruction_bits [end_pc] & BCODE_INSTRUCTION_START))
477 || ! (instruction_bits [handler_pc] & BCODE_INSTRUCTION_START))
479 error ("bad pc in exception_table");
484 if (handler_pc >= start_pc && handler_pc < end_pc)
485 warning ("exception handler inside code that is being protected");
487 add_handler (start_pc, end_pc,
488 lookup_label (handler_pc),
489 catch_type == 0 ? NULL_TREE
490 : get_class_constant (jcf, catch_type));
492 instruction_bits [handler_pc] |= BCODE_EXCEPTION_TARGET;
496 handle_nested_ranges ();
501 if (((PC != INVALID_PC
502 && instruction_bits [PC] & BCODE_TARGET) != 0)
505 PUSH_PENDING (lookup_label (PC));
508 /* Check if there are any more pending blocks in the current
509 subroutine. Because we push pending blocks in a
510 last-in-first-out order, and because we don't push anything
511 from our caller until we are done with this subroutine or
512 anything nested in it, then we are done if the top of the
513 pending_blocks stack is not in a subroutine, or it is in our
518 if (pending_blocks == NULL_TREE
519 || (subroutine_nesting (pending_blocks)
520 < subroutine_nesting (current_subr)))
522 int size = DECL_MAX_LOCALS(current_function_decl)+stack_pointer;
523 tree ret_map = LABEL_RETURN_TYPE_STATE (current_subr);
524 tmp = LABEL_RETURN_LABELS (current_subr);
526 /* FIXME: If we exit a subroutine via a throw, we might
527 have returned to an earlier caller. Obviously a
528 "ret" can only return one level, but a throw may
529 return many levels.*/
530 current_subr = LABEL_SUBR_CONTEXT (current_subr);
532 if (RETURN_MAP_ADJUSTED (ret_map))
534 /* Since we are done with this subroutine , set up
535 the (so far known) return address as pending -
536 with the merged type state. */
537 for ( ; tmp != NULL_TREE; tmp = TREE_CHAIN (tmp))
539 tree return_label = TREE_VALUE (tmp);
540 tree return_state = LABEL_TYPE_STATE (return_label);
541 if (return_state == NULL_TREE)
543 /* This means means we had not verified the
544 subroutine earlier, so this is the first jsr to
545 call it. In this case, the type_map of the return
546 address is just the current type_map - and that
547 is handled by the following PUSH_PENDING. */
551 /* In this case we have to do a merge. But first
552 restore the type_map for unused slots to those
553 that were in effect at the jsr. */
554 for (index = size; --index >= 0; )
556 type_map[index] = TREE_VEC_ELT (ret_map, index);
557 if (type_map[index] == TYPE_UNUSED)
559 = TREE_VEC_ELT (return_state, index);
562 PUSH_PENDING (return_label);
567 if (PC == INVALID_PC)
569 label = pending_blocks;
570 if (label == NULL_TREE)
571 break; /* We're done! */
572 pending_blocks = LABEL_PENDING_CHAIN (label);
573 LABEL_CHANGED (label) = 0;
575 if (LABEL_IN_SUBR (label))
576 current_subr = LABEL_SUBR_START (label);
578 current_subr = NULL_TREE;
580 /* Restore type_map and stack_pointer from
581 LABEL_TYPE_STATE (label), and continue
582 compiling from there. */
583 load_type_state (label);
584 PC = LABEL_PC (label);
586 else if (PC >= length)
587 VERIFICATION_ERROR ("falling through end of method");
589 /* fprintf (stderr, "** %d\n", PC); */
593 if (!(instruction_bits [PC] & BCODE_INSTRUCTION_START) && ! wide)
594 VERIFICATION_ERROR ("PC not at instruction start");
596 instruction_bits[PC] |= BCODE_VERIFIED;
598 eh_ranges = find_handler (oldpc);
600 op_code = byte_ops[PC++];
603 int is_static, is_putting;
606 case OPCODE_iconst_m1:
607 case OPCODE_iconst_0: case OPCODE_iconst_1: case OPCODE_iconst_2:
608 case OPCODE_iconst_3: case OPCODE_iconst_4: case OPCODE_iconst_5:
609 i = op_code - OPCODE_iconst_0;
612 if (byte_ops[PC] == OPCODE_newarray
613 || byte_ops[PC] == OPCODE_anewarray)
615 PUSH_TYPE (int_type_node); break;
616 case OPCODE_lconst_0: case OPCODE_lconst_1:
617 PUSH_TYPE (long_type_node); break;
618 case OPCODE_fconst_0: case OPCODE_fconst_1: case OPCODE_fconst_2:
619 PUSH_TYPE (float_type_node); break;
620 case OPCODE_dconst_0: case OPCODE_dconst_1:
621 PUSH_TYPE (double_type_node); break;
628 case OPCODE_iload: type = int_type_node; goto general_load;
629 case OPCODE_lload: type = long_type_node; goto general_load;
630 case OPCODE_fload: type = float_type_node; goto general_load;
631 case OPCODE_dload: type = double_type_node; goto general_load;
632 case OPCODE_aload: type = ptr_type_node; goto general_load;
634 index = wide ? IMMEDIATE_u2 : IMMEDIATE_u1;
637 case OPCODE_iload_0: type = int_type_node; index = 0; goto load;
638 case OPCODE_iload_1: type = int_type_node; index = 1; goto load;
639 case OPCODE_iload_2: type = int_type_node; index = 2; goto load;
640 case OPCODE_iload_3: type = int_type_node; index = 3; goto load;
641 case OPCODE_lload_0: type = long_type_node; index = 0; goto load;
642 case OPCODE_lload_1: type = long_type_node; index = 1; goto load;
643 case OPCODE_lload_2: type = long_type_node; index = 2; goto load;
644 case OPCODE_lload_3: type = long_type_node; index = 3; goto load;
645 case OPCODE_fload_0: type = float_type_node; index = 0; goto load;
646 case OPCODE_fload_1: type = float_type_node; index = 1; goto load;
647 case OPCODE_fload_2: type = float_type_node; index = 2; goto load;
648 case OPCODE_fload_3: type = float_type_node; index = 3; goto load;
649 case OPCODE_dload_0: type = double_type_node; index = 0; goto load;
650 case OPCODE_dload_1: type = double_type_node; index = 1; goto load;
651 case OPCODE_dload_2: type = double_type_node; index = 2; goto load;
652 case OPCODE_dload_3: type = double_type_node; index = 3; goto load;
653 case OPCODE_aload_0: type = ptr_type_node; index = 0; goto load;
654 case OPCODE_aload_1: type = ptr_type_node; index = 1; goto load;
655 case OPCODE_aload_2: type = ptr_type_node; index = 2; goto load;
656 case OPCODE_aload_3: type = ptr_type_node; index = 3; goto load;
659 || (index + TYPE_IS_WIDE (type)
660 >= DECL_MAX_LOCALS (current_function_decl)))
661 VERIFICATION_ERROR_WITH_INDEX
662 ("invalid local variable index %d in load");
663 tmp = type_map[index];
664 if (tmp == TYPE_UNKNOWN)
665 VERIFICATION_ERROR_WITH_INDEX
666 ("loading local variable %d which has unknown type");
667 else if (tmp == TYPE_SECOND
668 || (TYPE_IS_WIDE (type)
669 && type_map[index+1] != void_type_node)
670 || (type == ptr_type_node
671 ? TREE_CODE (tmp) != POINTER_TYPE
672 : type == int_type_node
673 ? (! INTEGRAL_TYPE_P (tmp) || TYPE_PRECISION (tmp) > 32)
675 VERIFICATION_ERROR_WITH_INDEX
676 ("loading local variable %d which has invalid type");
679 case OPCODE_istore: type = int_type_node; goto general_store;
680 case OPCODE_lstore: type = long_type_node; goto general_store;
681 case OPCODE_fstore: type = float_type_node; goto general_store;
682 case OPCODE_dstore: type = double_type_node; goto general_store;
683 case OPCODE_astore: type = object_ptr_type_node; goto general_store;
685 index = wide ? IMMEDIATE_u2 : IMMEDIATE_u1;
688 case OPCODE_istore_0: type = int_type_node; index = 0; goto store;
689 case OPCODE_istore_1: type = int_type_node; index = 1; goto store;
690 case OPCODE_istore_2: type = int_type_node; index = 2; goto store;
691 case OPCODE_istore_3: type = int_type_node; index = 3; goto store;
692 case OPCODE_lstore_0: type = long_type_node; index=0; goto store;
693 case OPCODE_lstore_1: type = long_type_node; index=1; goto store;
694 case OPCODE_lstore_2: type = long_type_node; index=2; goto store;
695 case OPCODE_lstore_3: type = long_type_node; index=3; goto store;
696 case OPCODE_fstore_0: type=float_type_node; index=0; goto store;
697 case OPCODE_fstore_1: type=float_type_node; index=1; goto store;
698 case OPCODE_fstore_2: type=float_type_node; index=2; goto store;
699 case OPCODE_fstore_3: type=float_type_node; index=3; goto store;
700 case OPCODE_dstore_0: type=double_type_node; index=0; goto store;
701 case OPCODE_dstore_1: type=double_type_node; index=1; goto store;
702 case OPCODE_dstore_2: type=double_type_node; index=2; goto store;
703 case OPCODE_dstore_3: type=double_type_node; index=3; goto store;
704 case OPCODE_astore_0: type = ptr_type_node; index = 0; goto store;
705 case OPCODE_astore_1: type = ptr_type_node; index = 1; goto store;
706 case OPCODE_astore_2: type = ptr_type_node; index = 2; goto store;
707 case OPCODE_astore_3: type = ptr_type_node; index = 3; goto store;
710 || (index + TYPE_IS_WIDE (type)
711 >= DECL_MAX_LOCALS (current_function_decl)))
713 VERIFICATION_ERROR_WITH_INDEX
714 ("invalid local variable index %d in store");
717 POP_TYPE_CONV (type, type, NULL);
718 type_map[index] = type;
720 /* If local variable changed, we need to reconsider eh handlers. */
721 prev_eh_ranges = NULL_EH_RANGE;
723 /* Allocate decl and rtx for this variable now, so if we're not
724 optmizing, we get a temporary that survives the whole method. */
725 find_local_variable (index, type, oldpc);
727 if (TYPE_IS_WIDE (type))
728 type_map[index+1] = TYPE_SECOND;
729 /* ... fall through to note_used ... */
731 /* For store or load, note that local variable INDEX is used.
732 This is needed to verify try-finally sub-routines. */
735 tree vec = LABEL_RETURN_TYPE_STATE (current_subr);
736 tree subr_vec = LABEL_TYPE_STATE (current_subr);
737 int len = 1 + TYPE_IS_WIDE (type);
740 if (TREE_VEC_ELT (vec, index) == TYPE_UNUSED)
741 TREE_VEC_ELT (vec, index) = TREE_VEC_ELT (subr_vec, index);
756 type = int_type_node; goto binop;
761 type = int_type_node; goto unop;
770 type = long_type_node; goto binop;
772 type = long_type_node; goto unop;
773 case OPCODE_fadd: case OPCODE_fsub:
774 case OPCODE_fmul: case OPCODE_fdiv: case OPCODE_frem:
775 type = float_type_node; goto binop;
777 type = float_type_node; goto unop;
778 case OPCODE_dadd: case OPCODE_dsub:
779 case OPCODE_dmul: case OPCODE_ddiv: case OPCODE_drem:
780 type = double_type_node; goto binop;
782 type = double_type_node; goto unop;
795 pop_type (int_type_node);
796 pop_type (long_type_node);
797 PUSH_TYPE (long_type_node);
800 index = wide ? IMMEDIATE_u2 : IMMEDIATE_u1;
803 if (index < 0 || index >= DECL_MAX_LOCALS (current_function_decl))
804 VERIFICATION_ERROR ("invalid local variable index in iinc");
805 tmp = type_map[index];
807 || ! INTEGRAL_TYPE_P (tmp) || TYPE_PRECISION (tmp) > 32)
808 VERIFICATION_ERROR ("invalid local variable type in iinc");
811 pop_type (int_type_node); PUSH_TYPE (long_type_node); break;
813 pop_type (int_type_node); PUSH_TYPE (float_type_node); break;
815 pop_type (int_type_node); PUSH_TYPE (double_type_node); break;
817 pop_type (long_type_node); PUSH_TYPE (int_type_node); break;
819 pop_type (long_type_node); PUSH_TYPE (float_type_node); break;
821 pop_type (long_type_node); PUSH_TYPE (double_type_node); break;
823 pop_type (float_type_node); PUSH_TYPE (int_type_node); break;
825 pop_type (float_type_node); PUSH_TYPE (long_type_node); break;
827 pop_type (float_type_node); PUSH_TYPE (double_type_node); break;
829 pop_type (double_type_node); PUSH_TYPE (int_type_node); break;
831 pop_type (double_type_node); PUSH_TYPE (long_type_node); break;
833 pop_type (double_type_node); PUSH_TYPE (float_type_node); break;
835 type = long_type_node; goto compare;
838 type = float_type_node; goto compare;
841 type = double_type_node; goto compare;
843 pop_type (type); pop_type (type);
844 PUSH_TYPE (int_type_node); break;
851 pop_type (int_type_node); goto cond;
853 case OPCODE_ifnonnull:
854 pop_type (ptr_type_node ); goto cond;
855 case OPCODE_if_icmpeq:
856 case OPCODE_if_icmpne:
857 case OPCODE_if_icmplt:
858 case OPCODE_if_icmpge:
859 case OPCODE_if_icmpgt:
860 case OPCODE_if_icmple:
861 pop_type (int_type_node); pop_type (int_type_node); goto cond;
862 case OPCODE_if_acmpeq:
863 case OPCODE_if_acmpne:
864 pop_type (object_ptr_type_node); pop_type (object_ptr_type_node);
867 PUSH_PENDING (lookup_label (oldpc + IMMEDIATE_s2));
870 PUSH_PENDING (lookup_label (oldpc + IMMEDIATE_s2));
874 switch (byte_ops[PC])
876 case OPCODE_iload: case OPCODE_lload:
877 case OPCODE_fload: case OPCODE_dload: case OPCODE_aload:
878 case OPCODE_istore: case OPCODE_lstore:
879 case OPCODE_fstore: case OPCODE_dstore: case OPCODE_astore:
885 VERIFICATION_ERROR ("invalid use of wide instruction");
888 case OPCODE_return: type = void_type_node; goto ret;
890 if ((TREE_CODE (return_type) == BOOLEAN_TYPE
891 || TREE_CODE (return_type) == CHAR_TYPE
892 || TREE_CODE (return_type) == INTEGER_TYPE)
893 && TYPE_PRECISION (return_type) <= 32)
898 case OPCODE_lreturn: type = long_type_node; goto ret;
899 case OPCODE_freturn: type = float_type_node; goto ret;
900 case OPCODE_dreturn: type = double_type_node; goto ret;
902 if (TREE_CODE (return_type) == POINTER_TYPE)
908 if (type != return_type)
909 VERIFICATION_ERROR ("incorrect ?return opcode");
910 if (type != void_type_node)
911 POP_TYPE(type, "return value has wrong type");
914 case OPCODE_getstatic: is_putting = 0; is_static = 1; goto field;
915 case OPCODE_putstatic: is_putting = 1; is_static = 1; goto field;
916 case OPCODE_getfield: is_putting = 0; is_static = 0; goto field;
917 case OPCODE_putfield: is_putting = 1; is_static = 0; goto field;
920 tree field_signature, field_type;
921 index = IMMEDIATE_u2;
922 if (index <= 0 || index >= JPOOL_SIZE(current_jcf))
923 VERIFICATION_ERROR_WITH_INDEX ("bad constant pool index %d");
924 if (JPOOL_TAG (current_jcf, index) != CONSTANT_Fieldref)
926 ("field instruction does not reference a Fieldref");
927 field_signature = COMPONENT_REF_SIGNATURE (¤t_jcf->cpool, index);
928 field_type = get_type_from_signature (field_signature);
930 POP_TYPE (field_type, "incorrect type for field");
933 int clindex = COMPONENT_REF_CLASS_INDEX (¤t_jcf->cpool,
935 tree self_type = get_class_constant (current_jcf, clindex);
936 /* Defer actual checking until next pass. */
937 POP_TYPE(self_type, "incorrect type for field reference");
940 PUSH_TYPE (field_type);
944 PUSH_TYPE (get_class_constant (jcf, IMMEDIATE_u2));
946 case OPCODE_dup: wide = 1; index = 0; goto dup;
947 case OPCODE_dup_x1: wide = 1; index = 1; goto dup;
948 case OPCODE_dup_x2: wide = 1; index = 2; goto dup;
949 case OPCODE_dup2: wide = 2; index = 0; goto dup;
950 case OPCODE_dup2_x1: wide = 2; index = 1; goto dup;
951 case OPCODE_dup2_x2: wide = 2; index = 2; goto dup;
953 if (wide + index > stack_pointer)
954 VERIFICATION_ERROR ("stack underflow - dup* operation");
955 type_stack_dup (wide, index);
958 case OPCODE_pop: index = 1; goto pop;
959 case OPCODE_pop2: index = 2; goto pop;
961 if (stack_pointer < index)
962 VERIFICATION_ERROR ("stack underflow");
963 stack_pointer -= index;
966 if (stack_pointer < 2)
967 VERIFICATION_ERROR ("stack underflow (in swap)");
970 tree type1 = stack_type_map[stack_pointer - 1];
971 tree type2 = stack_type_map[stack_pointer - 2];
972 if (type1 == void_type_node || type2 == void_type_node)
973 VERIFICATION_ERROR ("verifier (swap): double or long value");
974 stack_type_map[stack_pointer - 2] = type1;
975 stack_type_map[stack_pointer - 1] = type2;
978 case OPCODE_ldc: index = IMMEDIATE_u1; goto ldc;
981 index = IMMEDIATE_u2; goto ldc;
983 if (index <= 0 || index >= JPOOL_SIZE(current_jcf))
984 VERIFICATION_ERROR_WITH_INDEX ("bad constant pool index %d in ldc");
986 switch (JPOOL_TAG (current_jcf, index) & ~CONSTANT_ResolvedFlag)
988 case CONSTANT_Integer: type = int_type_node; goto check_ldc;
989 case CONSTANT_Float: type = float_type_node; goto check_ldc;
990 case CONSTANT_String: type = string_type_node; goto check_ldc;
991 case CONSTANT_Long: type = long_type_node; goto check_ldc;
992 case CONSTANT_Double: type = double_type_node; goto check_ldc;
994 if (TYPE_IS_WIDE (type) == (op_code == OPCODE_ldc2_w))
996 /* ... else fall through ... */
998 VERIFICATION_ERROR ("bad constant pool tag in ldc");
1000 if (type == int_type_node)
1002 i = TREE_INT_CST_LOW (get_constant (current_jcf, index));
1008 case OPCODE_invokevirtual:
1009 case OPCODE_invokespecial:
1010 case OPCODE_invokestatic:
1011 case OPCODE_invokeinterface:
1013 tree sig, method_name, method_type, self_type;
1014 int self_is_interface, tag;
1015 index = IMMEDIATE_u2;
1016 if (index <= 0 || index >= JPOOL_SIZE(current_jcf))
1017 VERIFICATION_ERROR_WITH_INDEX
1018 ("bad constant pool index %d for invoke");
1019 tag = JPOOL_TAG (current_jcf, index);
1020 if (op_code == OPCODE_invokeinterface)
1022 if (tag != CONSTANT_InterfaceMethodref)
1024 ("invokeinterface does not reference an InterfaceMethodref");
1028 if (tag != CONSTANT_Methodref)
1029 VERIFICATION_ERROR ("invoke does not reference a Methodref");
1031 sig = COMPONENT_REF_SIGNATURE (¤t_jcf->cpool, index);
1032 self_type = get_class_constant
1033 (current_jcf, COMPONENT_REF_CLASS_INDEX (¤t_jcf->cpool,
1035 if (! CLASS_LOADED_P (self_type))
1036 load_class (self_type, 1);
1037 self_is_interface = CLASS_INTERFACE (TYPE_NAME (self_type));
1038 method_name = COMPONENT_REF_NAME (¤t_jcf->cpool, index);
1039 method_type = parse_signature_string (IDENTIFIER_POINTER (sig),
1040 IDENTIFIER_LENGTH (sig));
1041 if (TREE_CODE (method_type) != FUNCTION_TYPE)
1042 VERIFICATION_ERROR ("bad method signature");
1043 pmessage = pop_argument_types (TYPE_ARG_TYPES (method_type));
1044 if (pmessage != NULL)
1046 message = "invalid argument type";
1047 goto pop_type_error;
1050 /* Can't invoke <clinit> */
1051 if (ID_CLINIT_P (method_name))
1052 VERIFICATION_ERROR ("invoke opcode can't invoke <clinit>");
1053 /* Apart invokespecial, can't invoke <init> */
1054 if (op_code != OPCODE_invokespecial && ID_INIT_P (method_name))
1055 VERIFICATION_ERROR ("invoke opcode can't invoke <init>");
1057 if (op_code != OPCODE_invokestatic)
1058 POP_TYPE (self_type,
1059 "stack type not subclass of invoked method's class");
1063 case OPCODE_invokeinterface:
1065 int nargs = IMMEDIATE_u1;
1066 int notZero = IMMEDIATE_u1;
1068 if (!nargs || notZero)
1070 ("invalid argument number in invokeinterface");
1071 /* If we verify/resolve the constant pool, as we should,
1072 this test (and the one just following) are redundant. */
1073 if (! self_is_interface)
1074 VERIFICATION_ERROR ("invokeinterface calls method not in interface");
1077 if (self_is_interface)
1078 VERIFICATION_ERROR ("method in interface called");
1082 if (TREE_TYPE (method_type) != void_type_node)
1083 PUSH_TYPE (TREE_TYPE (method_type));
1087 case OPCODE_arraylength:
1088 /* Type checking actually made during code generation */
1089 pop_type( ptr_type_node );
1090 PUSH_TYPE( int_type_node );
1093 /* Q&D verification *or* more checking done during code generation
1094 for byte/boolean/char/short, the value popped is a int coerced
1095 into the right type before being stored. */
1096 case OPCODE_iastore: type = int_type_node; goto astore;
1097 case OPCODE_lastore: type = long_type_node; goto astore;
1098 case OPCODE_fastore: type = float_type_node; goto astore;
1099 case OPCODE_dastore: type = double_type_node; goto astore;
1100 case OPCODE_aastore: type = ptr_type_node; goto astore;
1101 case OPCODE_bastore: type = int_type_node; goto astore;
1102 case OPCODE_castore: type = int_type_node; goto astore;
1103 case OPCODE_sastore: type = int_type_node; goto astore;
1105 /* FIXME - need better verification here */
1106 pop_type (type); /* new value */
1107 pop_type (int_type_node); /* index */
1108 pop_type (ptr_type_node); /* array */
1111 /* Q&D verification *or* more checking done during code generation
1112 for byte/boolean/char/short, the value pushed is a int. */
1113 case OPCODE_iaload: type = int_type_node; goto aload;
1114 case OPCODE_laload: type = long_type_node; goto aload;
1115 case OPCODE_faload: type = float_type_node; goto aload;
1116 case OPCODE_daload: type = double_type_node; goto aload;
1117 case OPCODE_aaload: type = ptr_type_node; goto aload;
1118 case OPCODE_baload: type = promote_type (byte_type_node); goto aload;
1119 case OPCODE_caload: type = promote_type (char_type_node); goto aload;
1120 case OPCODE_saload: type = promote_type (short_type_node); goto aload;
1122 pop_type (int_type_node);
1123 tmp = pop_type (ptr_type_node);
1124 if (is_array_type_p (tmp))
1125 type = TYPE_ARRAY_ELEMENT (TREE_TYPE (tmp));
1126 else if (tmp != TYPE_NULL)
1127 VERIFICATION_ERROR ("array load from non-array type");
1131 case OPCODE_anewarray:
1132 type = get_class_constant (current_jcf, IMMEDIATE_u2);
1133 type = promote_type (type);
1136 case OPCODE_newarray:
1137 index = IMMEDIATE_u1;
1138 type = decode_newarray_type (index);
1139 if (type == NULL_TREE)
1140 VERIFICATION_ERROR ("invalid type code in newarray opcode");
1144 if (int_value >= 0 && prevpc >= 0)
1146 /* If previous instruction pushed int constant,
1147 we want to use it. */
1148 switch (byte_ops[prevpc])
1150 case OPCODE_iconst_0: case OPCODE_iconst_1:
1151 case OPCODE_iconst_2: case OPCODE_iconst_3:
1152 case OPCODE_iconst_4: case OPCODE_iconst_5:
1153 case OPCODE_bipush: case OPCODE_sipush:
1154 case OPCODE_ldc: case OPCODE_ldc_w:
1162 type = build_java_array_type (type, int_value);
1163 pop_type (int_type_node);
1167 case OPCODE_multianewarray:
1170 index = IMMEDIATE_u2;
1171 ndim = IMMEDIATE_u1;
1174 VERIFICATION_ERROR ("number of dimension lower that 1 in multianewarray" );
1176 for( i = 0; i < ndim; i++ )
1177 pop_type (int_type_node);
1178 PUSH_TYPE (get_class_constant (current_jcf, index));
1182 case OPCODE_aconst_null:
1183 PUSH_TYPE (ptr_type_node);
1187 /* FIXME: athrow also empties the stack. */
1188 POP_TYPE (throwable_type_node, "missing throwable at athrow" );
1192 case OPCODE_checkcast:
1193 POP_TYPE (object_ptr_type_node,
1194 "checkcast operand is not a pointer");
1195 type = get_class_constant (current_jcf, IMMEDIATE_u2);
1198 case OPCODE_instanceof:
1199 POP_TYPE (object_ptr_type_node,
1200 "instanceof operand is not a pointer");
1201 get_class_constant (current_jcf, IMMEDIATE_u2);
1202 PUSH_TYPE (int_type_node);
1205 case OPCODE_tableswitch:
1209 POP_TYPE (int_type_node, "missing int for tableswitch");
1213 VERIFICATION_ERROR ("bad alignment in tableswitch pad");
1215 PUSH_PENDING (lookup_label (oldpc+IMMEDIATE_s4));
1217 high = IMMEDIATE_s4;
1220 VERIFICATION_ERROR ("unsorted low/high value in tableswitch");
1222 while (low++ <= high)
1223 PUSH_PENDING (lookup_label (oldpc + IMMEDIATE_s4));
1228 case OPCODE_lookupswitch:
1230 jint npairs, last = 0, not_registered = 1;
1232 POP_TYPE (int_type_node, "missing int for lookupswitch");
1236 VERIFICATION_ERROR ("bad alignment in lookupswitch pad");
1239 PUSH_PENDING (lookup_label (oldpc+IMMEDIATE_s4));
1240 npairs = IMMEDIATE_s4;
1243 VERIFICATION_ERROR ("invalid number of targets in lookupswitch");
1247 int match = IMMEDIATE_s4;
1250 else if (last >= match)
1251 VERIFICATION_ERROR ("unsorted match value in lookupswitch");
1254 PUSH_PENDING (lookup_label (oldpc + IMMEDIATE_s4));
1260 case OPCODE_monitorenter:
1262 case OPCODE_monitorexit:
1263 pop_type (ptr_type_node);
1267 PUSH_PENDING (lookup_label (oldpc + IMMEDIATE_s4));
1273 tree target = lookup_label (oldpc + IMMEDIATE_s2);
1274 tree return_label = lookup_label (PC);
1275 PUSH_TYPE (return_address_type_node);
1276 /* The return label chain will be null if this is the first
1277 time we've seen this jsr target. */
1278 if (LABEL_RETURN_LABEL (target) == NULL_TREE)
1280 tree return_type_map;
1281 int nlocals = DECL_MAX_LOCALS (current_function_decl);
1282 index = nlocals + DECL_MAX_STACK (current_function_decl);
1283 return_type_map = make_tree_vec (index);
1284 while (index > nlocals)
1285 TREE_VEC_ELT (return_type_map, --index) = TYPE_UNKNOWN;
1287 TREE_VEC_ELT (return_type_map, --index) = TYPE_UNUSED;
1288 LABEL_RETURN_LABEL (target)
1289 = build_decl (LABEL_DECL, NULL_TREE, TREE_TYPE (target));
1290 LABEL_PC (LABEL_RETURN_LABEL (target)) = -1;
1291 LABEL_RETURN_TYPE_STATE (target) = return_type_map;
1292 LABEL_IS_SUBR_START (target) = 1;
1293 LABEL_IN_SUBR (target) = 1;
1294 LABEL_SUBR_START (target) = target;
1295 LABEL_SUBR_CONTEXT (target) = current_subr;
1297 else if (! LABEL_IS_SUBR_START (target)
1298 || LABEL_SUBR_CONTEXT (target) != current_subr)
1299 VERIFICATION_ERROR ("label part of different subroutines");
1301 i = merge_type_state (target);
1305 VERIFICATION_ERROR ("types could not be merged at jsr");
1306 push_pending_label (target);
1308 current_subr = target;
1310 /* Chain return_pc onto LABEL_RETURN_LABELS (target) if needed. */
1311 if (! value_member (return_label, LABEL_RETURN_LABELS (target)))
1313 LABEL_RETURN_LABELS (target)
1314 = tree_cons (NULL_TREE, return_label,
1315 LABEL_RETURN_LABELS (target));
1318 if (LABEL_VERIFIED (target))
1320 tree return_map = LABEL_RETURN_TYPE_STATE (target);
1321 int len = TREE_VEC_LENGTH (return_map);
1322 stack_pointer = len - DECL_MAX_LOCALS (current_function_decl);
1325 if (TREE_VEC_ELT (return_map, len) != TYPE_UNUSED)
1326 type_map[len] = TREE_VEC_ELT (return_map, len);
1328 current_subr = LABEL_SUBR_CONTEXT (target);
1329 if (RETURN_MAP_ADJUSTED (return_map))
1330 PUSH_PENDING (return_label);
1337 if (current_subr == NULL)
1338 VERIFICATION_ERROR ("ret instruction not in a jsr subroutine");
1341 tree ret_map = LABEL_RETURN_TYPE_STATE (current_subr);
1342 int size = DECL_MAX_LOCALS(current_function_decl)+stack_pointer;
1343 index = wide ? IMMEDIATE_u2 : IMMEDIATE_u1;
1346 if (index < 0 || index >= DECL_MAX_LOCALS (current_function_decl)
1347 || type_map[index] != TYPE_RETURN_ADDR)
1348 VERIFICATION_ERROR ("invalid ret index");
1350 /* The next chunk of code is similar to an inlined version of
1351 * merge_type_state (LABEL_RETURN_LABEL (current_subr)).
1352 * The main differences are that LABEL_RETURN_LABEL is
1353 * pre-allocated by the jsr (but we don't know the size then);
1354 * and that we have to handle TYPE_UNUSED. */
1356 if (! RETURN_MAP_ADJUSTED (ret_map))
1357 { /* First return from this subroutine - fix stack pointer. */
1358 TREE_VEC_LENGTH (ret_map) = size;
1359 for (index = size; --index >= 0; )
1361 if (TREE_VEC_ELT (ret_map, index) != TYPE_UNUSED)
1362 TREE_VEC_ELT (ret_map, index) = type_map[index];
1364 RETURN_MAP_ADJUSTED (ret_map) = 1;
1368 if (TREE_VEC_LENGTH (ret_map) != size)
1369 VERIFICATION_ERROR ("inconsistent stack size on ret");
1370 for (index = 0; index < size; index++)
1372 tree type = TREE_VEC_ELT (ret_map, index);
1373 if (type != TYPE_UNUSED)
1375 type = merge_types (type, type_map [index]);
1376 TREE_VEC_ELT (ret_map, index) = type;
1377 if (type == TYPE_UNKNOWN)
1379 if (index >= size - stack_pointer)
1381 ("inconsistent types on ret from jsr");
1383 else if (TYPE_IS_WIDE (type))
1395 error ("unknown opcode %d@pc=%d during verification", op_code, PC-1);
1401 /* The following test is true if we have entered or exited an exception
1402 handler range *or* we have done a store to a local variable.
1403 In either case we need to consider any exception handlers that
1404 might "follow" this instruction. */
1406 if (eh_ranges != prev_eh_ranges)
1408 int save_stack_pointer = stack_pointer;
1409 int index = DECL_MAX_LOCALS (current_function_decl);
1410 tree save_type = type_map[index];
1411 tree save_current_subr = current_subr;
1412 struct eh_range *ranges = find_handler (oldpc);
1414 for (; ranges != NULL_EH_RANGE; ranges = ranges->outer)
1416 tree chain = ranges->handlers;
1418 /* We need to determine if the handler is part of current_subr.
1419 The are two cases: (1) The exception catch range
1420 is entirely within current_subr. In that case the handler
1421 is also part of current_subr.
1422 (2) Some of the catch range is not in current_subr.
1423 In that case, the handler is *not* part of current_subr.
1425 Figuring out which is the case is not necessarily obvious,
1426 in the presence of clever code generators (and obfuscators).
1427 We make a simplifying assumption that in case (2) we
1428 have that the current_subr is entirely within the catch range.
1429 In that case we can assume if that if a caller (the jsr) of
1430 a subroutine is within the catch range, then the handler is
1431 *not* part of the subroutine, and vice versa. */
1433 current_subr = save_current_subr;
1434 for ( ; current_subr != NULL_TREE;
1435 current_subr = LABEL_SUBR_CONTEXT (current_subr))
1437 tree return_labels = LABEL_RETURN_LABELS (current_subr);
1438 /* There could be multiple return_labels, but
1439 we only need to check one. */
1440 int return_pc = LABEL_PC (TREE_VALUE (return_labels));
1441 if (return_pc <= ranges->start_pc
1442 || return_pc > ranges->end_pc)
1446 for ( ; chain != NULL_TREE; chain = TREE_CHAIN (chain))
1448 tree handler = TREE_VALUE (chain);
1449 tree type = TREE_PURPOSE (chain);
1450 if (type == NULL_TREE) /* a finally handler */
1451 type = throwable_type_node;
1452 type_map[index] = promote_type (type);
1454 PUSH_PENDING (handler);
1457 stack_pointer = save_stack_pointer;
1458 current_subr = save_current_subr;
1459 type_map[index] = save_type;
1460 prev_eh_ranges = eh_ranges;
1465 error ("verification error at PC=%d", oldpc);
1466 if (message != NULL)
1467 error ("%s", message);
1468 error ("%s", pmessage);
1472 message = "stack overflow";
1475 message = "program counter out of range";
1478 error ("verification error at PC=%d", oldpc);
1479 error (message, index);
1482 error ("verification error at PC=%d", oldpc);
1483 error ("%s", message);