1 /* Language-independent node constructors for parse phase of GNU compiler.
2 Copyright (C) 1987, 1988, 1992 Free Software Foundation, Inc.
4 This file is part of GNU CC.
6 GNU CC is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 2, or (at your option)
11 GNU CC is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with GNU CC; see the file COPYING. If not, write to
18 the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */
21 /* This file contains the low level primitives for operating on tree nodes,
22 including allocation, list operations, interning of identifiers,
23 construction of data type nodes and statement nodes,
24 and construction of type conversion nodes. It also contains
25 tables index by tree code that describe how to take apart
28 It is intended to be language-independent, but occasionally
29 calls language-dependent routines defined (for C) in typecheck.c.
31 The low-level allocation routines oballoc and permalloc
32 are used also for allocating many other kinds of objects
33 by all passes of the compiler. */
43 #define obstack_chunk_alloc xmalloc
44 #define obstack_chunk_free free
46 /* Tree nodes of permanent duration are allocated in this obstack.
47 They are the identifier nodes, and everything outside of
48 the bodies and parameters of function definitions. */
50 struct obstack permanent_obstack;
52 /* The initial RTL, and all ..._TYPE nodes, in a function
53 are allocated in this obstack. Usually they are freed at the
54 end of the function, but if the function is inline they are saved.
55 For top-level functions, this is maybepermanent_obstack.
56 Separate obstacks are made for nested functions. */
58 struct obstack *function_maybepermanent_obstack;
60 /* This is the function_maybepermanent_obstack for top-level functions. */
62 struct obstack maybepermanent_obstack;
64 /* The contents of the current function definition are allocated
65 in this obstack, and all are freed at the end of the function.
66 For top-level functions, this is temporary_obstack.
67 Separate obstacks are made for nested functions. */
69 struct obstack *function_obstack;
71 /* This is used for reading initializers of global variables. */
73 struct obstack temporary_obstack;
75 /* The tree nodes of an expression are allocated
76 in this obstack, and all are freed at the end of the expression. */
78 struct obstack momentary_obstack;
80 /* The tree nodes of a declarator are allocated
81 in this obstack, and all are freed when the declarator
84 static struct obstack temp_decl_obstack;
86 /* This points at either permanent_obstack
87 or the current function_maybepermanent_obstack. */
89 struct obstack *saveable_obstack;
91 /* This is same as saveable_obstack during parse and expansion phase;
92 it points to the current function's obstack during optimization.
93 This is the obstack to be used for creating rtl objects. */
95 struct obstack *rtl_obstack;
97 /* This points at either permanent_obstack or the current function_obstack. */
99 struct obstack *current_obstack;
101 /* This points at either permanent_obstack or the current function_obstack
102 or momentary_obstack. */
104 struct obstack *expression_obstack;
106 /* Stack of obstack selections for push_obstacks and pop_obstacks. */
110 struct obstack_stack *next;
111 struct obstack *current;
112 struct obstack *saveable;
113 struct obstack *expression;
117 struct obstack_stack *obstack_stack;
119 /* Obstack for allocating struct obstack_stack entries. */
121 static struct obstack obstack_stack_obstack;
123 /* Addresses of first objects in some obstacks.
124 This is for freeing their entire contents. */
125 char *maybepermanent_firstobj;
126 char *temporary_firstobj;
127 char *momentary_firstobj;
128 char *temp_decl_firstobj;
130 /* Nonzero means all ..._TYPE nodes should be allocated permanently. */
132 int all_types_permanent;
134 /* Stack of places to restore the momentary obstack back to. */
136 struct momentary_level
138 /* Pointer back to previous such level. */
139 struct momentary_level *prev;
140 /* First object allocated within this level. */
142 /* Value of expression_obstack saved at entry to this level. */
143 struct obstack *obstack;
146 struct momentary_level *momentary_stack;
148 /* Table indexed by tree code giving a string containing a character
149 classifying the tree code. Possibilities are
150 t, d, s, c, r, <, 1, 2 and e. See tree.def for details. */
152 #define DEFTREECODE(SYM, NAME, TYPE, LENGTH) TYPE,
154 char *standard_tree_code_type[] = {
159 /* Table indexed by tree code giving number of expression
160 operands beyond the fixed part of the node structure.
161 Not used for types or decls. */
163 #define DEFTREECODE(SYM, NAME, TYPE, LENGTH) LENGTH,
165 int standard_tree_code_length[] = {
170 /* Names of tree components.
171 Used for printing out the tree and error messages. */
172 #define DEFTREECODE(SYM, NAME, TYPE, LEN) NAME,
174 char *standard_tree_code_name[] = {
179 /* Table indexed by tree code giving a string containing a character
180 classifying the tree code. Possibilities are
181 t, d, s, c, r, e, <, 1 and 2. See tree.def for details. */
183 char **tree_code_type;
185 /* Table indexed by tree code giving number of expression
186 operands beyond the fixed part of the node structure.
187 Not used for types or decls. */
189 int *tree_code_length;
191 /* Table indexed by tree code giving name of tree code, as a string. */
193 char **tree_code_name;
195 /* Statistics-gathering stuff. */
216 int tree_node_counts[(int)all_kinds];
217 int tree_node_sizes[(int)all_kinds];
218 int id_string_size = 0;
220 char *tree_node_kind_names[] = {
238 /* Hash table for uniquizing IDENTIFIER_NODEs by name. */
240 #define MAX_HASH_TABLE 1009
241 static tree hash_table[MAX_HASH_TABLE]; /* id hash buckets */
243 /* 0 while creating built-in identifiers. */
244 static int do_identifier_warnings;
246 /* Unique id for next decl created. */
247 static int next_decl_uid;
249 extern char *mode_name[];
251 void gcc_obstack_init ();
252 static tree stabilize_reference_1 ();
254 /* Init the principal obstacks. */
259 gcc_obstack_init (&obstack_stack_obstack);
260 gcc_obstack_init (&permanent_obstack);
262 gcc_obstack_init (&temporary_obstack);
263 temporary_firstobj = (char *) obstack_alloc (&temporary_obstack, 0);
264 gcc_obstack_init (&momentary_obstack);
265 momentary_firstobj = (char *) obstack_alloc (&momentary_obstack, 0);
266 gcc_obstack_init (&maybepermanent_obstack);
267 maybepermanent_firstobj
268 = (char *) obstack_alloc (&maybepermanent_obstack, 0);
269 gcc_obstack_init (&temp_decl_obstack);
270 temp_decl_firstobj = (char *) obstack_alloc (&temp_decl_obstack, 0);
272 function_obstack = &temporary_obstack;
273 function_maybepermanent_obstack = &maybepermanent_obstack;
274 current_obstack = &permanent_obstack;
275 expression_obstack = &permanent_obstack;
276 rtl_obstack = saveable_obstack = &permanent_obstack;
278 /* Init the hash table of identifiers. */
279 bzero (hash_table, sizeof hash_table);
283 gcc_obstack_init (obstack)
284 struct obstack *obstack;
286 /* Let particular systems override the size of a chunk. */
287 #ifndef OBSTACK_CHUNK_SIZE
288 #define OBSTACK_CHUNK_SIZE 0
290 /* Let them override the alloc and free routines too. */
291 #ifndef OBSTACK_CHUNK_ALLOC
292 #define OBSTACK_CHUNK_ALLOC xmalloc
294 #ifndef OBSTACK_CHUNK_FREE
295 #define OBSTACK_CHUNK_FREE free
297 _obstack_begin (obstack, OBSTACK_CHUNK_SIZE, 0,
298 (void *(*) ()) OBSTACK_CHUNK_ALLOC,
299 (void (*) ()) OBSTACK_CHUNK_FREE);
302 /* Save all variables describing the current status into the structure *P.
303 This is used before starting a nested function. */
309 p->all_types_permanent = all_types_permanent;
310 p->momentary_stack = momentary_stack;
311 p->maybepermanent_firstobj = maybepermanent_firstobj;
312 p->momentary_firstobj = momentary_firstobj;
313 p->function_obstack = function_obstack;
314 p->function_maybepermanent_obstack = function_maybepermanent_obstack;
315 p->current_obstack = current_obstack;
316 p->expression_obstack = expression_obstack;
317 p->saveable_obstack = saveable_obstack;
318 p->rtl_obstack = rtl_obstack;
320 function_obstack = (struct obstack *) xmalloc (sizeof (struct obstack));
321 gcc_obstack_init (function_obstack);
323 function_maybepermanent_obstack
324 = (struct obstack *) xmalloc (sizeof (struct obstack));
325 gcc_obstack_init (function_maybepermanent_obstack);
327 current_obstack = &permanent_obstack;
328 expression_obstack = &permanent_obstack;
329 rtl_obstack = saveable_obstack = &permanent_obstack;
331 momentary_firstobj = (char *) obstack_finish (&momentary_obstack);
332 maybepermanent_firstobj
333 = (char *) obstack_finish (function_maybepermanent_obstack);
336 /* Restore all variables describing the current status from the structure *P.
337 This is used after a nested function. */
340 restore_tree_status (p)
343 all_types_permanent = p->all_types_permanent;
344 momentary_stack = p->momentary_stack;
346 obstack_free (&momentary_obstack, momentary_firstobj);
347 obstack_free (function_obstack, 0);
348 obstack_free (function_maybepermanent_obstack, 0);
349 free (function_obstack);
351 momentary_firstobj = p->momentary_firstobj;
352 maybepermanent_firstobj = p->maybepermanent_firstobj;
353 function_obstack = p->function_obstack;
354 function_maybepermanent_obstack = p->function_maybepermanent_obstack;
355 current_obstack = p->current_obstack;
356 expression_obstack = p->expression_obstack;
357 saveable_obstack = p->saveable_obstack;
358 rtl_obstack = p->rtl_obstack;
361 /* Start allocating on the temporary (per function) obstack.
362 This is done in start_function before parsing the function body,
363 and before each initialization at top level, and to go back
364 to temporary allocation after doing end_temporary_allocation. */
367 temporary_allocation ()
369 /* Note that function_obstack at top level points to temporary_obstack.
370 But within a nested function context, it is a separate obstack. */
371 current_obstack = function_obstack;
372 expression_obstack = function_obstack;
373 rtl_obstack = saveable_obstack = function_maybepermanent_obstack;
377 /* Start allocating on the permanent obstack but don't
378 free the temporary data. After calling this, call
379 `permanent_allocation' to fully resume permanent allocation status. */
382 end_temporary_allocation ()
384 current_obstack = &permanent_obstack;
385 expression_obstack = &permanent_obstack;
386 rtl_obstack = saveable_obstack = &permanent_obstack;
389 /* Resume allocating on the temporary obstack, undoing
390 effects of `end_temporary_allocation'. */
393 resume_temporary_allocation ()
395 current_obstack = function_obstack;
396 expression_obstack = function_obstack;
397 rtl_obstack = saveable_obstack = function_maybepermanent_obstack;
400 /* While doing temporary allocation, switch to allocating in such a
401 way as to save all nodes if the function is inlined. Call
402 resume_temporary_allocation to go back to ordinary temporary
406 saveable_allocation ()
408 /* Note that function_obstack at top level points to temporary_obstack.
409 But within a nested function context, it is a separate obstack. */
410 expression_obstack = current_obstack = saveable_obstack;
413 /* Switch to current obstack CURRENT and maybepermanent obstack SAVEABLE,
414 recording the previously current obstacks on a stack.
415 This does not free any storage in any obstack. */
418 push_obstacks (current, saveable)
419 struct obstack *current, *saveable;
421 struct obstack_stack *p
422 = (struct obstack_stack *) obstack_alloc (&obstack_stack_obstack,
423 (sizeof (struct obstack_stack)));
425 p->current = current_obstack;
426 p->saveable = saveable_obstack;
427 p->expression = expression_obstack;
428 p->rtl = rtl_obstack;
429 p->next = obstack_stack;
432 current_obstack = current;
433 expression_obstack = current;
434 rtl_obstack = saveable_obstack = saveable;
437 /* Save the current set of obstacks, but don't change them. */
440 push_obstacks_nochange ()
442 struct obstack_stack *p
443 = (struct obstack_stack *) obstack_alloc (&obstack_stack_obstack,
444 (sizeof (struct obstack_stack)));
446 p->current = current_obstack;
447 p->saveable = saveable_obstack;
448 p->expression = expression_obstack;
449 p->rtl = rtl_obstack;
450 p->next = obstack_stack;
454 /* Pop the obstack selection stack. */
459 struct obstack_stack *p = obstack_stack;
460 obstack_stack = p->next;
462 current_obstack = p->current;
463 saveable_obstack = p->saveable;
464 expression_obstack = p->expression;
465 rtl_obstack = p->rtl;
467 obstack_free (&obstack_stack_obstack, p);
470 /* Nonzero if temporary allocation is currently in effect.
471 Zero if currently doing permanent allocation. */
474 allocation_temporary_p ()
476 return current_obstack != &permanent_obstack;
479 /* Go back to allocating on the permanent obstack
480 and free everything in the temporary obstack.
481 This is done in finish_function after fully compiling a function. */
484 permanent_allocation ()
486 /* Free up previous temporary obstack data */
487 obstack_free (&temporary_obstack, temporary_firstobj);
488 obstack_free (&momentary_obstack, momentary_firstobj);
489 obstack_free (&maybepermanent_obstack, maybepermanent_firstobj);
490 obstack_free (&temp_decl_obstack, temp_decl_firstobj);
492 current_obstack = &permanent_obstack;
493 expression_obstack = &permanent_obstack;
494 rtl_obstack = saveable_obstack = &permanent_obstack;
497 /* Save permanently everything on the maybepermanent_obstack. */
502 maybepermanent_firstobj
503 = (char *) obstack_alloc (function_maybepermanent_obstack, 0);
507 preserve_initializer ()
510 = (char *) obstack_alloc (&temporary_obstack, 0);
512 = (char *) obstack_alloc (&momentary_obstack, 0);
513 maybepermanent_firstobj
514 = (char *) obstack_alloc (function_maybepermanent_obstack, 0);
517 /* Start allocating new rtl in current_obstack.
518 Use resume_temporary_allocation
519 to go back to allocating rtl in saveable_obstack. */
522 rtl_in_current_obstack ()
524 rtl_obstack = current_obstack;
527 /* Temporarily allocate rtl from saveable_obstack. Return 1 if we were
528 previously allocating it from current_obstack. */
531 rtl_in_saveable_obstack ()
533 if (rtl_obstack == current_obstack)
535 rtl_obstack = saveable_obstack;
542 /* Allocate SIZE bytes in the current obstack
543 and return a pointer to them.
544 In practice the current obstack is always the temporary one. */
550 return (char *) obstack_alloc (current_obstack, size);
553 /* Free the object PTR in the current obstack
554 as well as everything allocated since PTR.
555 In practice the current obstack is always the temporary one. */
561 obstack_free (current_obstack, ptr);
564 /* Allocate SIZE bytes in the permanent obstack
565 and return a pointer to them. */
571 return (char *) obstack_alloc (&permanent_obstack, size);
574 /* Allocate NELEM items of SIZE bytes in the permanent obstack
575 and return a pointer to them. The storage is cleared before
576 returning the value. */
579 perm_calloc (nelem, size)
583 char *rval = (char *) obstack_alloc (&permanent_obstack, nelem * size);
584 bzero (rval, nelem * size);
588 /* Allocate SIZE bytes in the saveable obstack
589 and return a pointer to them. */
595 return (char *) obstack_alloc (saveable_obstack, size);
598 /* Print out which obstack an object is in. */
601 debug_obstack (object)
604 struct obstack *obstack = NULL;
605 char *obstack_name = NULL;
608 for (p = outer_function_chain; p; p = p->next)
610 if (_obstack_allocated_p (p->function_obstack, object))
612 obstack = p->function_obstack;
613 obstack_name = "containing function obstack";
615 if (_obstack_allocated_p (p->function_maybepermanent_obstack, object))
617 obstack = p->function_maybepermanent_obstack;
618 obstack_name = "containing function maybepermanent obstack";
622 if (_obstack_allocated_p (&obstack_stack_obstack, object))
624 obstack = &obstack_stack_obstack;
625 obstack_name = "obstack_stack_obstack";
627 else if (_obstack_allocated_p (function_obstack, object))
629 obstack = function_obstack;
630 obstack_name = "function obstack";
632 else if (_obstack_allocated_p (&permanent_obstack, object))
634 obstack = &permanent_obstack;
635 obstack_name = "permanent_obstack";
637 else if (_obstack_allocated_p (&momentary_obstack, object))
639 obstack = &momentary_obstack;
640 obstack_name = "momentary_obstack";
642 else if (_obstack_allocated_p (function_maybepermanent_obstack, object))
644 obstack = function_maybepermanent_obstack;
645 obstack_name = "function maybepermanent obstack";
647 else if (_obstack_allocated_p (&temp_decl_obstack, object))
649 obstack = &temp_decl_obstack;
650 obstack_name = "temp_decl_obstack";
653 /* Check to see if the object is in the free area of the obstack. */
656 if (object >= obstack->next_free
657 && object < obstack->chunk_limit)
658 fprintf (stderr, "object in free portion of obstack %s.\n",
661 fprintf (stderr, "object allocated from %s.\n", obstack_name);
664 fprintf (stderr, "object not allocated from any obstack.\n");
667 /* Return 1 if OBJ is in the permanent obstack.
668 This is slow, and should be used only for debugging.
669 Use TREE_PERMANENT for other purposes. */
672 object_permanent_p (obj)
675 return _obstack_allocated_p (&permanent_obstack, obj);
678 /* Start a level of momentary allocation.
679 In C, each compound statement has its own level
680 and that level is freed at the end of each statement.
681 All expression nodes are allocated in the momentary allocation level. */
686 struct momentary_level *tem
687 = (struct momentary_level *) obstack_alloc (&momentary_obstack,
688 sizeof (struct momentary_level));
689 tem->prev = momentary_stack;
690 tem->base = (char *) obstack_base (&momentary_obstack);
691 tem->obstack = expression_obstack;
692 momentary_stack = tem;
693 expression_obstack = &momentary_obstack;
696 /* Free all the storage in the current momentary-allocation level.
697 In C, this happens at the end of each statement. */
702 obstack_free (&momentary_obstack, momentary_stack->base);
705 /* Discard a level of momentary allocation.
706 In C, this happens at the end of each compound statement.
707 Restore the status of expression node allocation
708 that was in effect before this level was created. */
713 struct momentary_level *tem = momentary_stack;
714 momentary_stack = tem->prev;
715 expression_obstack = tem->obstack;
716 obstack_free (&momentary_obstack, tem);
719 /* Call when starting to parse a declaration:
720 make expressions in the declaration last the length of the function.
721 Returns an argument that should be passed to resume_momentary later. */
726 register int tem = expression_obstack == &momentary_obstack;
727 expression_obstack = saveable_obstack;
731 /* Call when finished parsing a declaration:
732 restore the treatment of node-allocation that was
733 in effect before the suspension.
734 YES should be the value previously returned by suspend_momentary. */
737 resume_momentary (yes)
741 expression_obstack = &momentary_obstack;
744 /* Init the tables indexed by tree code.
745 Note that languages can add to these tables to define their own codes. */
750 tree_code_type = (char **) xmalloc (sizeof (standard_tree_code_type));
751 tree_code_length = (int *) xmalloc (sizeof (standard_tree_code_length));
752 tree_code_name = (char **) xmalloc (sizeof (standard_tree_code_name));
753 bcopy (standard_tree_code_type, tree_code_type,
754 sizeof (standard_tree_code_type));
755 bcopy (standard_tree_code_length, tree_code_length,
756 sizeof (standard_tree_code_length));
757 bcopy (standard_tree_code_name, tree_code_name,
758 sizeof (standard_tree_code_name));
761 /* Return a newly allocated node of code CODE.
762 Initialize the node's unique id and its TREE_PERMANENT flag.
763 For decl and type nodes, some other fields are initialized.
764 The rest of the node is initialized to zero.
766 Achoo! I got a code in the node. */
773 register int type = TREE_CODE_CLASS (code);
775 register struct obstack *obstack = current_obstack;
777 register tree_node_kind kind;
781 case 'd': /* A decl node */
782 #ifdef GATHER_STATISTICS
785 length = sizeof (struct tree_decl);
786 /* All decls in an inline function need to be saved. */
787 if (obstack != &permanent_obstack)
788 obstack = saveable_obstack;
789 /* PARM_DECLs always go on saveable_obstack, not permanent,
790 even though we may make them before the function turns
791 on temporary allocation. */
792 else if (code == PARM_DECL)
793 obstack = function_maybepermanent_obstack;
796 case 't': /* a type node */
797 #ifdef GATHER_STATISTICS
800 length = sizeof (struct tree_type);
801 /* All data types are put where we can preserve them if nec. */
802 if (obstack != &permanent_obstack)
803 obstack = all_types_permanent ? &permanent_obstack : saveable_obstack;
806 case 'b': /* a lexical block */
807 #ifdef GATHER_STATISTICS
810 length = sizeof (struct tree_block);
811 /* All BLOCK nodes are put where we can preserve them if nec. */
812 if (obstack != &permanent_obstack)
813 obstack = saveable_obstack;
816 case 's': /* an expression with side effects */
817 #ifdef GATHER_STATISTICS
821 case 'r': /* a reference */
822 #ifdef GATHER_STATISTICS
826 case 'e': /* an expression */
827 case '<': /* a comparison expression */
828 case '1': /* a unary arithmetic expression */
829 case '2': /* a binary arithmetic expression */
830 #ifdef GATHER_STATISTICS
834 obstack = expression_obstack;
835 /* All BIND_EXPR nodes are put where we can preserve them if nec. */
836 if (code == BIND_EXPR && obstack != &permanent_obstack)
837 obstack = saveable_obstack;
838 length = sizeof (struct tree_exp)
839 + (tree_code_length[(int) code] - 1) * sizeof (char *);
842 case 'c': /* a constant */
843 #ifdef GATHER_STATISTICS
846 obstack = expression_obstack;
847 /* We can't use tree_code_length for this, since the number of words
848 is machine-dependent due to varying alignment of `double'. */
849 if (code == REAL_CST)
851 length = sizeof (struct tree_real_cst);
855 case 'x': /* something random, like an identifier. */
856 #ifdef GATHER_STATISTICS
857 if (code == IDENTIFIER_NODE)
859 else if (code == OP_IDENTIFIER)
861 else if (code == TREE_VEC)
866 length = sizeof (struct tree_common)
867 + tree_code_length[(int) code] * sizeof (char *);
868 /* Identifier nodes are always permanent since they are
869 unique in a compiler run. */
870 if (code == IDENTIFIER_NODE) obstack = &permanent_obstack;
873 t = (tree) obstack_alloc (obstack, length);
875 #ifdef GATHER_STATISTICS
876 tree_node_counts[(int)kind]++;
877 tree_node_sizes[(int)kind] += length;
880 /* We assume here that the length of a tree node is a multiple of the
881 size of an int. Rounding up won't work because it would clobber
883 for (i = (length / sizeof (int)) - 1; i >= 0; i--)
886 TREE_SET_CODE (t, code);
887 if (obstack == &permanent_obstack)
888 TREE_PERMANENT (t) = 1;
893 TREE_SIDE_EFFECTS (t) = 1;
894 TREE_TYPE (t) = void_type_node;
898 if (code != FUNCTION_DECL)
899 DECL_IN_SYSTEM_HEADER (t)
900 = in_system_header && (obstack == &permanent_obstack);
902 DECL_SOURCE_LINE (t) = lineno;
903 DECL_SOURCE_FILE (t) = (input_filename) ? input_filename : "<built-in>";
904 DECL_UID (t) = next_decl_uid++;
909 static unsigned next_type_uid = 1;
911 TYPE_UID (t) = next_type_uid++;
914 TYPE_MAIN_VARIANT (t) = t;
918 TREE_CONSTANT (t) = 1;
925 /* Return a new node with the same contents as NODE
926 except that its TREE_CHAIN is zero and it has a fresh uid. */
933 register enum tree_code code = TREE_CODE (node);
937 switch (TREE_CODE_CLASS (code))
939 case 'd': /* A decl node */
940 length = sizeof (struct tree_decl);
943 case 't': /* a type node */
944 length = sizeof (struct tree_type);
947 case 'b': /* a lexical block node */
948 length = sizeof (struct tree_block);
951 case 'r': /* a reference */
952 case 'e': /* an expression */
953 case 's': /* an expression with side effects */
954 case '<': /* a comparison expression */
955 case '1': /* a unary arithmetic expression */
956 case '2': /* a binary arithmetic expression */
957 length = sizeof (struct tree_exp)
958 + (tree_code_length[(int) code] - 1) * sizeof (char *);
961 case 'c': /* a constant */
962 /* We can't use tree_code_length for this, since the number of words
963 is machine-dependent due to varying alignment of `double'. */
964 if (code == REAL_CST)
966 length = sizeof (struct tree_real_cst);
970 case 'x': /* something random, like an identifier. */
971 length = sizeof (struct tree_common)
972 + tree_code_length[(int) code] * sizeof (char *);
973 if (code == TREE_VEC)
974 length += (TREE_VEC_LENGTH (node) - 1) * sizeof (char *);
977 t = (tree) obstack_alloc (current_obstack, length);
979 for (i = (length / sizeof (int)) - 1; i >= 0; i--)
980 ((int *) t)[i] = ((int *) node)[i];
984 TREE_PERMANENT (t) = (current_obstack == &permanent_obstack);
989 /* Return a copy of a chain of nodes, chained through the TREE_CHAIN field.
990 For example, this can copy a list made of TREE_LIST nodes. */
997 register tree prev, next;
1002 head = prev = copy_node (list);
1003 next = TREE_CHAIN (list);
1006 TREE_CHAIN (prev) = copy_node (next);
1007 prev = TREE_CHAIN (prev);
1008 next = TREE_CHAIN (next);
1015 /* Return an IDENTIFIER_NODE whose name is TEXT (a null-terminated string).
1016 If an identifier with that name has previously been referred to,
1017 the same node is returned this time. */
1020 get_identifier (text)
1021 register char *text;
1026 register int len, hash_len;
1028 /* Compute length of text in len. */
1029 for (len = 0; text[len]; len++);
1031 /* Decide how much of that length to hash on */
1033 if (warn_id_clash && len > id_clash_len)
1034 hash_len = id_clash_len;
1036 /* Compute hash code */
1037 hi = hash_len * 613 + (unsigned)text[0];
1038 for (i = 1; i < hash_len; i += 2)
1039 hi = ((hi * 613) + (unsigned)(text[i]));
1041 hi &= (1 << HASHBITS) - 1;
1042 hi %= MAX_HASH_TABLE;
1044 /* Search table for identifier */
1045 for (idp = hash_table[hi]; idp; idp = TREE_CHAIN (idp))
1046 if (IDENTIFIER_LENGTH (idp) == len
1047 && IDENTIFIER_POINTER (idp)[0] == text[0]
1048 && !bcmp (IDENTIFIER_POINTER (idp), text, len))
1049 return idp; /* <-- return if found */
1051 /* Not found; optionally warn about a similar identifier */
1052 if (warn_id_clash && do_identifier_warnings && len >= id_clash_len)
1053 for (idp = hash_table[hi]; idp; idp = TREE_CHAIN (idp))
1054 if (!strncmp (IDENTIFIER_POINTER (idp), text, id_clash_len))
1056 warning ("`%s' and `%s' identical in first %d characters",
1057 IDENTIFIER_POINTER (idp), text, id_clash_len);
1061 if (tree_code_length[(int) IDENTIFIER_NODE] < 0)
1062 abort (); /* set_identifier_size hasn't been called. */
1064 /* Not found, create one, add to chain */
1065 idp = make_node (IDENTIFIER_NODE);
1066 IDENTIFIER_LENGTH (idp) = len;
1067 #ifdef GATHER_STATISTICS
1068 id_string_size += len;
1071 IDENTIFIER_POINTER (idp) = obstack_copy0 (&permanent_obstack, text, len);
1073 TREE_CHAIN (idp) = hash_table[hi];
1074 hash_table[hi] = idp;
1075 return idp; /* <-- return if created */
1078 /* Enable warnings on similar identifiers (if requested).
1079 Done after the built-in identifiers are created. */
1082 start_identifier_warnings ()
1084 do_identifier_warnings = 1;
1087 /* Record the size of an identifier node for the language in use.
1088 SIZE is the total size in bytes.
1089 This is called by the language-specific files. This must be
1090 called before allocating any identifiers. */
1093 set_identifier_size (size)
1096 tree_code_length[(int) IDENTIFIER_NODE]
1097 = (size - sizeof (struct tree_common)) / sizeof (tree);
1100 /* Return a newly constructed INTEGER_CST node whose constant value
1101 is specified by the two ints LOW and HI.
1102 The TREE_TYPE is set to `int'.
1104 This function should be used via the `build_int_2' macro. */
1107 build_int_2_wide (low, hi)
1108 HOST_WIDE_INT low, hi;
1110 register tree t = make_node (INTEGER_CST);
1111 TREE_INT_CST_LOW (t) = low;
1112 TREE_INT_CST_HIGH (t) = hi;
1113 TREE_TYPE (t) = integer_type_node;
1117 /* Return a new REAL_CST node whose type is TYPE and value is D. */
1120 build_real (type, d)
1126 /* Check for valid float value for this type on this target machine;
1127 if not, can print error message and store a valid value in D. */
1128 #ifdef CHECK_FLOAT_VALUE
1129 CHECK_FLOAT_VALUE (TYPE_MODE (type), d);
1132 v = make_node (REAL_CST);
1133 TREE_TYPE (v) = type;
1134 TREE_REAL_CST (v) = d;
1138 /* Return a new REAL_CST node whose type is TYPE
1139 and whose value is the integer value of the INTEGER_CST node I. */
1141 #if !defined (REAL_IS_NOT_DOUBLE) || defined (REAL_ARITHMETIC)
1144 real_value_from_int_cst (i)
1148 #ifdef REAL_ARITHMETIC
1149 REAL_VALUE_FROM_INT (d, TREE_INT_CST_LOW (i), TREE_INT_CST_HIGH (i));
1150 #else /* not REAL_ARITHMETIC */
1151 if (TREE_INT_CST_HIGH (i) < 0 && ! TREE_UNSIGNED (TREE_TYPE (i)))
1153 d = (double) (~ TREE_INT_CST_HIGH (i));
1154 d *= ((double) ((HOST_WIDE_INT) 1 << (HOST_BITS_PER_WIDE_INT / 2))
1155 * (double) ((HOST_WIDE_INT) 1 << (HOST_BITS_PER_WIDE_INT / 2)));
1156 d += (double) (unsigned HOST_WIDE_INT) (~ TREE_INT_CST_LOW (i));
1161 d = (double) (unsigned HOST_WIDE_INT) TREE_INT_CST_HIGH (i);
1162 d *= ((double) ((HOST_WIDE_INT) 1 << (HOST_BITS_PER_WIDE_INT / 2))
1163 * (double) ((HOST_WIDE_INT) 1 << (HOST_BITS_PER_WIDE_INT / 2)));
1164 d += (double) (unsigned HOST_WIDE_INT) TREE_INT_CST_LOW (i);
1166 #endif /* not REAL_ARITHMETIC */
1170 /* This function can't be implemented if we can't do arithmetic
1171 on the float representation. */
1174 build_real_from_int_cst (type, i)
1181 v = make_node (REAL_CST);
1182 TREE_TYPE (v) = type;
1184 d = REAL_VALUE_TRUNCATE (TYPE_MODE (type), real_value_from_int_cst (i));
1185 /* Check for valid float value for this type on this target machine;
1186 if not, can print error message and store a valid value in D. */
1187 #ifdef CHECK_FLOAT_VALUE
1188 CHECK_FLOAT_VALUE (TYPE_MODE (type), d);
1191 TREE_REAL_CST (v) = d;
1195 #endif /* not REAL_IS_NOT_DOUBLE, or REAL_ARITHMETIC */
1197 /* Return a newly constructed STRING_CST node whose value is
1198 the LEN characters at STR.
1199 The TREE_TYPE is not initialized. */
1202 build_string (len, str)
1206 register tree s = make_node (STRING_CST);
1207 TREE_STRING_LENGTH (s) = len;
1208 TREE_STRING_POINTER (s) = obstack_copy0 (saveable_obstack, str, len);
1212 /* Return a newly constructed COMPLEX_CST node whose value is
1213 specified by the real and imaginary parts REAL and IMAG.
1214 Both REAL and IMAG should be constant nodes.
1215 The TREE_TYPE is not initialized. */
1218 build_complex (real, imag)
1221 register tree t = make_node (COMPLEX_CST);
1222 TREE_REALPART (t) = real;
1223 TREE_IMAGPART (t) = imag;
1227 /* Build a newly constructed TREE_VEC node of length LEN. */
1233 register int length = (len-1) * sizeof (tree) + sizeof (struct tree_vec);
1234 register struct obstack *obstack = current_obstack;
1237 #ifdef GATHER_STATISTICS
1238 tree_node_counts[(int)vec_kind]++;
1239 tree_node_sizes[(int)vec_kind] += length;
1242 t = (tree) obstack_alloc (obstack, length);
1244 for (i = (length / sizeof (int)) - 1; i >= 0; i--)
1247 TREE_SET_CODE (t, TREE_VEC);
1248 TREE_VEC_LENGTH (t) = len;
1249 if (obstack == &permanent_obstack)
1250 TREE_PERMANENT (t) = 1;
1255 /* Return 1 if EXPR is the integer constant zero. */
1258 integer_zerop (expr)
1263 return (TREE_CODE (expr) == INTEGER_CST
1264 && TREE_INT_CST_LOW (expr) == 0
1265 && TREE_INT_CST_HIGH (expr) == 0);
1268 /* Return 1 if EXPR is the integer constant one. */
1276 return (TREE_CODE (expr) == INTEGER_CST
1277 && TREE_INT_CST_LOW (expr) == 1
1278 && TREE_INT_CST_HIGH (expr) == 0);
1281 /* Return 1 if EXPR is an integer containing all 1's
1282 in as much precision as it contains. */
1285 integer_all_onesp (expr)
1293 if (TREE_CODE (expr) != INTEGER_CST)
1296 uns = TREE_UNSIGNED (TREE_TYPE (expr));
1298 return TREE_INT_CST_LOW (expr) == -1 && TREE_INT_CST_HIGH (expr) == -1;
1300 prec = TYPE_PRECISION (TREE_TYPE (expr));
1301 if (prec >= HOST_BITS_PER_WIDE_INT)
1303 int high_value, shift_amount;
1305 shift_amount = prec - HOST_BITS_PER_WIDE_INT;
1307 if (shift_amount > HOST_BITS_PER_WIDE_INT)
1308 /* Can not handle precisions greater than twice the host int size. */
1310 else if (shift_amount == HOST_BITS_PER_WIDE_INT)
1311 /* Shifting by the host word size is undefined according to the ANSI
1312 standard, so we must handle this as a special case. */
1315 high_value = ((HOST_WIDE_INT) 1 << shift_amount) - 1;
1317 return TREE_INT_CST_LOW (expr) == -1
1318 && TREE_INT_CST_HIGH (expr) == high_value;
1321 return TREE_INT_CST_LOW (expr) == ((HOST_WIDE_INT) 1 << prec) - 1;
1324 /* Return 1 if EXPR is an integer constant that is a power of 2 (i.e., has only
1328 integer_pow2p (expr)
1331 HOST_WIDE_INT high, low;
1335 if (TREE_CODE (expr) != INTEGER_CST)
1338 high = TREE_INT_CST_HIGH (expr);
1339 low = TREE_INT_CST_LOW (expr);
1341 if (high == 0 && low == 0)
1344 return ((high == 0 && (low & (low - 1)) == 0)
1345 || (low == 0 && (high & (high - 1)) == 0));
1348 /* Return 1 if EXPR is the real constant zero. */
1356 return (TREE_CODE (expr) == REAL_CST
1357 && REAL_VALUES_EQUAL (TREE_REAL_CST (expr), dconst0));
1360 /* Return 1 if EXPR is the real constant one. */
1368 return (TREE_CODE (expr) == REAL_CST
1369 && REAL_VALUES_EQUAL (TREE_REAL_CST (expr), dconst1));
1372 /* Return 1 if EXPR is the real constant two. */
1380 return (TREE_CODE (expr) == REAL_CST
1381 && REAL_VALUES_EQUAL (TREE_REAL_CST (expr), dconst2));
1384 /* Nonzero if EXP is a constant or a cast of a constant. */
1387 really_constant_p (exp)
1390 /* This is not quite the same as STRIP_NOPS. It does more. */
1391 while (TREE_CODE (exp) == NOP_EXPR
1392 || TREE_CODE (exp) == CONVERT_EXPR
1393 || TREE_CODE (exp) == NON_LVALUE_EXPR)
1394 exp = TREE_OPERAND (exp, 0);
1395 return TREE_CONSTANT (exp);
1398 /* Return first list element whose TREE_VALUE is ELEM.
1399 Return 0 if ELEM is not it LIST. */
1402 value_member (elem, list)
1407 if (elem == TREE_VALUE (list))
1409 list = TREE_CHAIN (list);
1414 /* Return first list element whose TREE_PURPOSE is ELEM.
1415 Return 0 if ELEM is not it LIST. */
1418 purpose_member (elem, list)
1423 if (elem == TREE_PURPOSE (list))
1425 list = TREE_CHAIN (list);
1430 /* Return first list element whose BINFO_TYPE is ELEM.
1431 Return 0 if ELEM is not it LIST. */
1434 binfo_member (elem, list)
1439 if (elem == BINFO_TYPE (list))
1441 list = TREE_CHAIN (list);
1446 /* Return nonzero if ELEM is part of the chain CHAIN. */
1449 chain_member (elem, chain)
1456 chain = TREE_CHAIN (chain);
1462 /* Return the length of a chain of nodes chained through TREE_CHAIN.
1463 We expect a null pointer to mark the end of the chain.
1464 This is the Lisp primitive `length'. */
1471 register int len = 0;
1473 for (tail = t; tail; tail = TREE_CHAIN (tail))
1479 /* Concatenate two chains of nodes (chained through TREE_CHAIN)
1480 by modifying the last node in chain 1 to point to chain 2.
1481 This is the Lisp primitive `nconc'. */
1491 for (t = op1; TREE_CHAIN (t); t = TREE_CHAIN (t))
1492 if (t == op2) abort (); /* Circularity being created */
1493 TREE_CHAIN (t) = op2;
1499 /* Return the last node in a chain of nodes (chained through TREE_CHAIN). */
1503 register tree chain;
1507 while (next = TREE_CHAIN (chain))
1512 /* Reverse the order of elements in the chain T,
1513 and return the new head of the chain (old last element). */
1519 register tree prev = 0, decl, next;
1520 for (decl = t; decl; decl = next)
1522 next = TREE_CHAIN (decl);
1523 TREE_CHAIN (decl) = prev;
1529 /* Given a chain CHAIN of tree nodes,
1530 construct and return a list of those nodes. */
1536 tree result = NULL_TREE;
1537 tree in_tail = chain;
1538 tree out_tail = NULL_TREE;
1542 tree next = tree_cons (NULL_TREE, in_tail, NULL_TREE);
1544 TREE_CHAIN (out_tail) = next;
1548 in_tail = TREE_CHAIN (in_tail);
1554 /* Return a newly created TREE_LIST node whose
1555 purpose and value fields are PARM and VALUE. */
1558 build_tree_list (parm, value)
1561 register tree t = make_node (TREE_LIST);
1562 TREE_PURPOSE (t) = parm;
1563 TREE_VALUE (t) = value;
1567 /* Similar, but build on the temp_decl_obstack. */
1570 build_decl_list (parm, value)
1574 register struct obstack *ambient_obstack = current_obstack;
1575 current_obstack = &temp_decl_obstack;
1576 node = build_tree_list (parm, value);
1577 current_obstack = ambient_obstack;
1581 /* Return a newly created TREE_LIST node whose
1582 purpose and value fields are PARM and VALUE
1583 and whose TREE_CHAIN is CHAIN. */
1586 tree_cons (purpose, value, chain)
1587 tree purpose, value, chain;
1590 register tree node = make_node (TREE_LIST);
1593 register tree node = (tree) obstack_alloc (current_obstack, sizeof (struct tree_list));
1594 #ifdef GATHER_STATISTICS
1595 tree_node_counts[(int)x_kind]++;
1596 tree_node_sizes[(int)x_kind] += sizeof (struct tree_list);
1599 for (i = (sizeof (struct tree_common) / sizeof (int)) - 1; i >= 0; i--)
1600 ((int *) node)[i] = 0;
1602 TREE_SET_CODE (node, TREE_LIST);
1603 if (current_obstack == &permanent_obstack)
1604 TREE_PERMANENT (node) = 1;
1607 TREE_CHAIN (node) = chain;
1608 TREE_PURPOSE (node) = purpose;
1609 TREE_VALUE (node) = value;
1613 /* Similar, but build on the temp_decl_obstack. */
1616 decl_tree_cons (purpose, value, chain)
1617 tree purpose, value, chain;
1620 register struct obstack *ambient_obstack = current_obstack;
1621 current_obstack = &temp_decl_obstack;
1622 node = tree_cons (purpose, value, chain);
1623 current_obstack = ambient_obstack;
1627 /* Same as `tree_cons' but make a permanent object. */
1630 perm_tree_cons (purpose, value, chain)
1631 tree purpose, value, chain;
1634 register struct obstack *ambient_obstack = current_obstack;
1635 current_obstack = &permanent_obstack;
1637 node = tree_cons (purpose, value, chain);
1638 current_obstack = ambient_obstack;
1642 /* Same as `tree_cons', but make this node temporary, regardless. */
1645 temp_tree_cons (purpose, value, chain)
1646 tree purpose, value, chain;
1649 register struct obstack *ambient_obstack = current_obstack;
1650 current_obstack = &temporary_obstack;
1652 node = tree_cons (purpose, value, chain);
1653 current_obstack = ambient_obstack;
1657 /* Same as `tree_cons', but save this node if the function's RTL is saved. */
1660 saveable_tree_cons (purpose, value, chain)
1661 tree purpose, value, chain;
1664 register struct obstack *ambient_obstack = current_obstack;
1665 current_obstack = saveable_obstack;
1667 node = tree_cons (purpose, value, chain);
1668 current_obstack = ambient_obstack;
1672 /* Return the size nominally occupied by an object of type TYPE
1673 when it resides in memory. The value is measured in units of bytes,
1674 and its data type is that normally used for type sizes
1675 (which is the first type created by make_signed_type or
1676 make_unsigned_type). */
1679 size_in_bytes (type)
1682 if (type == error_mark_node)
1683 return integer_zero_node;
1684 type = TYPE_MAIN_VARIANT (type);
1685 if (TYPE_SIZE (type) == 0)
1687 incomplete_type_error (NULL_TREE, type);
1688 return integer_zero_node;
1690 return size_binop (CEIL_DIV_EXPR, TYPE_SIZE (type),
1691 size_int (BITS_PER_UNIT));
1694 /* Return the size of TYPE (in bytes) as an integer,
1695 or return -1 if the size can vary. */
1698 int_size_in_bytes (type)
1702 if (type == error_mark_node)
1704 type = TYPE_MAIN_VARIANT (type);
1705 if (TYPE_SIZE (type) == 0)
1707 if (TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
1709 size = TREE_INT_CST_LOW (TYPE_SIZE (type));
1710 return (size + BITS_PER_UNIT - 1) / BITS_PER_UNIT;
1713 /* Return, as an INTEGER_CST node, the number of elements for
1714 TYPE (which is an ARRAY_TYPE) minus one.
1715 This counts only elements of the top array. */
1718 array_type_nelts (type)
1721 tree index_type = TYPE_DOMAIN (type);
1722 return (tree_int_cst_equal (TYPE_MIN_VALUE (index_type), integer_zero_node)
1723 ? TYPE_MAX_VALUE (index_type)
1724 : fold (build (MINUS_EXPR, integer_type_node,
1725 TYPE_MAX_VALUE (index_type),
1726 TYPE_MIN_VALUE (index_type))));
1729 /* Return nonzero if arg is static -- a reference to an object in
1730 static storage. This is not the same as the C meaning of `static'. */
1736 switch (TREE_CODE (arg))
1741 return TREE_STATIC (arg) || DECL_EXTERNAL (arg);
1748 return staticp (TREE_OPERAND (arg, 0));
1751 return TREE_CONSTANT (TREE_OPERAND (arg, 0));
1754 if (TREE_CODE (TYPE_SIZE (TREE_TYPE (arg))) == INTEGER_CST
1755 && TREE_CODE (TREE_OPERAND (arg, 1)) == INTEGER_CST)
1756 return staticp (TREE_OPERAND (arg, 0));
1762 /* This should be applied to any node which may be used in more than one place,
1763 but must be evaluated only once. Normally, the code generator would
1764 reevaluate the node each time; this forces it to compute it once and save
1765 the result. This is done by encapsulating the node in a SAVE_EXPR. */
1771 register tree t = fold (expr);
1773 /* We don't care about whether this can be used as an lvalue in this
1775 while (TREE_CODE (t) == NON_LVALUE_EXPR)
1776 t = TREE_OPERAND (t, 0);
1778 /* If the tree evaluates to a constant, then we don't want to hide that
1779 fact (i.e. this allows further folding, and direct checks for constants).
1780 However, a read-only object that has side effects cannot be bypassed.
1781 Since it is no problem to reevaluate literals, we just return the
1784 if (TREE_CONSTANT (t) || (TREE_READONLY (t) && ! TREE_SIDE_EFFECTS (t))
1785 || TREE_CODE (t) == SAVE_EXPR)
1788 t = build (SAVE_EXPR, TREE_TYPE (expr), t, current_function_decl, NULL_TREE);
1790 /* This expression might be placed ahead of a jump to ensure that the
1791 value was computed on both sides of the jump. So make sure it isn't
1792 eliminated as dead. */
1793 TREE_SIDE_EFFECTS (t) = 1;
1797 /* Stabilize a reference so that we can use it any number of times
1798 without causing its operands to be evaluated more than once.
1799 Returns the stabilized reference.
1801 Also allows conversion expressions whose operands are references.
1802 Any other kind of expression is returned unchanged. */
1805 stabilize_reference (ref)
1808 register tree result;
1809 register enum tree_code code = TREE_CODE (ref);
1816 /* No action is needed in this case. */
1822 case FIX_TRUNC_EXPR:
1823 case FIX_FLOOR_EXPR:
1824 case FIX_ROUND_EXPR:
1826 result = build_nt (code, stabilize_reference (TREE_OPERAND (ref, 0)));
1830 result = build_nt (INDIRECT_REF,
1831 stabilize_reference_1 (TREE_OPERAND (ref, 0)));
1835 result = build_nt (COMPONENT_REF,
1836 stabilize_reference (TREE_OPERAND (ref, 0)),
1837 TREE_OPERAND (ref, 1));
1841 result = build_nt (BIT_FIELD_REF,
1842 stabilize_reference (TREE_OPERAND (ref, 0)),
1843 stabilize_reference_1 (TREE_OPERAND (ref, 1)),
1844 stabilize_reference_1 (TREE_OPERAND (ref, 2)));
1848 result = build_nt (ARRAY_REF,
1849 stabilize_reference (TREE_OPERAND (ref, 0)),
1850 stabilize_reference_1 (TREE_OPERAND (ref, 1)));
1853 /* If arg isn't a kind of lvalue we recognize, make no change.
1854 Caller should recognize the error for an invalid lvalue. */
1859 return error_mark_node;
1862 TREE_TYPE (result) = TREE_TYPE (ref);
1863 TREE_READONLY (result) = TREE_READONLY (ref);
1864 TREE_SIDE_EFFECTS (result) = TREE_SIDE_EFFECTS (ref);
1865 TREE_THIS_VOLATILE (result) = TREE_THIS_VOLATILE (ref);
1866 TREE_RAISES (result) = TREE_RAISES (ref);
1871 /* Subroutine of stabilize_reference; this is called for subtrees of
1872 references. Any expression with side-effects must be put in a SAVE_EXPR
1873 to ensure that it is only evaluated once.
1875 We don't put SAVE_EXPR nodes around everything, because assigning very
1876 simple expressions to temporaries causes us to miss good opportunities
1877 for optimizations. Among other things, the opportunity to fold in the
1878 addition of a constant into an addressing mode often gets lost, e.g.
1879 "y[i+1] += x;". In general, we take the approach that we should not make
1880 an assignment unless we are forced into it - i.e., that any non-side effect
1881 operator should be allowed, and that cse should take care of coalescing
1882 multiple utterances of the same expression should that prove fruitful. */
1885 stabilize_reference_1 (e)
1888 register tree result;
1889 register int length;
1890 register enum tree_code code = TREE_CODE (e);
1892 /* We cannot ignore const expressions because it might be a reference
1893 to a const array but whose index contains side-effects. But we can
1894 ignore things that are actual constant or that already have been
1895 handled by this function. */
1897 if (TREE_CONSTANT (e) || code == SAVE_EXPR)
1900 switch (TREE_CODE_CLASS (code))
1910 /* If the expression has side-effects, then encase it in a SAVE_EXPR
1911 so that it will only be evaluated once. */
1912 /* The reference (r) and comparison (<) classes could be handled as
1913 below, but it is generally faster to only evaluate them once. */
1914 if (TREE_SIDE_EFFECTS (e))
1915 return save_expr (e);
1919 /* Constants need no processing. In fact, we should never reach
1924 /* Recursively stabilize each operand. */
1925 result = build_nt (code, stabilize_reference_1 (TREE_OPERAND (e, 0)),
1926 stabilize_reference_1 (TREE_OPERAND (e, 1)));
1930 /* Recursively stabilize each operand. */
1931 result = build_nt (code, stabilize_reference_1 (TREE_OPERAND (e, 0)));
1935 TREE_TYPE (result) = TREE_TYPE (e);
1936 TREE_READONLY (result) = TREE_READONLY (e);
1937 TREE_SIDE_EFFECTS (result) = TREE_SIDE_EFFECTS (e);
1938 TREE_THIS_VOLATILE (result) = TREE_THIS_VOLATILE (e);
1939 TREE_RAISES (result) = TREE_RAISES (e);
1944 /* Low-level constructors for expressions. */
1946 /* Build an expression of code CODE, data type TYPE,
1947 and operands as specified by the arguments ARG1 and following arguments.
1948 Expressions and reference nodes can be created this way.
1949 Constants, decls, types and misc nodes cannot be. */
1956 enum tree_code code;
1958 register int length;
1963 code = va_arg (p, enum tree_code);
1964 t = make_node (code);
1965 length = tree_code_length[(int) code];
1966 TREE_TYPE (t) = va_arg (p, tree);
1970 /* This is equivalent to the loop below, but faster. */
1971 register tree arg0 = va_arg (p, tree);
1972 register tree arg1 = va_arg (p, tree);
1973 TREE_OPERAND (t, 0) = arg0;
1974 TREE_OPERAND (t, 1) = arg1;
1975 if ((arg0 && TREE_SIDE_EFFECTS (arg0))
1976 || (arg1 && TREE_SIDE_EFFECTS (arg1)))
1977 TREE_SIDE_EFFECTS (t) = 1;
1979 = (arg0 && TREE_RAISES (arg0)) || (arg1 && TREE_RAISES (arg1));
1981 else if (length == 1)
1983 register tree arg0 = va_arg (p, tree);
1985 /* Call build1 for this! */
1986 if (TREE_CODE_CLASS (code) != 's')
1988 TREE_OPERAND (t, 0) = arg0;
1989 if (arg0 && TREE_SIDE_EFFECTS (arg0))
1990 TREE_SIDE_EFFECTS (t) = 1;
1991 TREE_RAISES (t) = (arg0 && TREE_RAISES (arg0));
1995 for (i = 0; i < length; i++)
1997 register tree operand = va_arg (p, tree);
1998 TREE_OPERAND (t, i) = operand;
2001 if (TREE_SIDE_EFFECTS (operand))
2002 TREE_SIDE_EFFECTS (t) = 1;
2003 if (TREE_RAISES (operand))
2004 TREE_RAISES (t) = 1;
2012 /* Same as above, but only builds for unary operators.
2013 Saves lions share of calls to `build'; cuts down use
2014 of varargs, which is expensive for RISC machines. */
2016 build1 (code, type, node)
2017 enum tree_code code;
2021 register struct obstack *obstack = current_obstack;
2022 register int i, length;
2023 register tree_node_kind kind;
2026 #ifdef GATHER_STATISTICS
2027 if (TREE_CODE_CLASS (code) == 'r')
2033 obstack = expression_obstack;
2034 length = sizeof (struct tree_exp);
2036 t = (tree) obstack_alloc (obstack, length);
2038 #ifdef GATHER_STATISTICS
2039 tree_node_counts[(int)kind]++;
2040 tree_node_sizes[(int)kind] += length;
2043 for (i = (length / sizeof (int)) - 1; i >= 0; i--)
2046 TREE_TYPE (t) = type;
2047 TREE_SET_CODE (t, code);
2049 if (obstack == &permanent_obstack)
2050 TREE_PERMANENT (t) = 1;
2052 TREE_OPERAND (t, 0) = node;
2055 if (TREE_SIDE_EFFECTS (node))
2056 TREE_SIDE_EFFECTS (t) = 1;
2057 if (TREE_RAISES (node))
2058 TREE_RAISES (t) = 1;
2064 /* Similar except don't specify the TREE_TYPE
2065 and leave the TREE_SIDE_EFFECTS as 0.
2066 It is permissible for arguments to be null,
2067 or even garbage if their values do not matter. */
2074 register enum tree_code code;
2076 register int length;
2081 code = va_arg (p, enum tree_code);
2082 t = make_node (code);
2083 length = tree_code_length[(int) code];
2085 for (i = 0; i < length; i++)
2086 TREE_OPERAND (t, i) = va_arg (p, tree);
2092 /* Similar to `build_nt', except we build
2093 on the temp_decl_obstack, regardless. */
2096 build_parse_node (va_alist)
2099 register struct obstack *ambient_obstack = expression_obstack;
2101 register enum tree_code code;
2103 register int length;
2106 expression_obstack = &temp_decl_obstack;
2110 code = va_arg (p, enum tree_code);
2111 t = make_node (code);
2112 length = tree_code_length[(int) code];
2114 for (i = 0; i < length; i++)
2115 TREE_OPERAND (t, i) = va_arg (p, tree);
2118 expression_obstack = ambient_obstack;
2123 /* Commented out because this wants to be done very
2124 differently. See cp-lex.c. */
2126 build_op_identifier (op1, op2)
2129 register tree t = make_node (OP_IDENTIFIER);
2130 TREE_PURPOSE (t) = op1;
2131 TREE_VALUE (t) = op2;
2136 /* Create a DECL_... node of code CODE, name NAME and data type TYPE.
2137 We do NOT enter this node in any sort of symbol table.
2139 layout_decl is used to set up the decl's storage layout.
2140 Other slots are initialized to 0 or null pointers. */
2143 build_decl (code, name, type)
2144 enum tree_code code;
2149 t = make_node (code);
2151 /* if (type == error_mark_node)
2152 type = integer_type_node; */
2153 /* That is not done, deliberately, so that having error_mark_node
2154 as the type can suppress useless errors in the use of this variable. */
2156 DECL_NAME (t) = name;
2157 DECL_ASSEMBLER_NAME (t) = name;
2158 TREE_TYPE (t) = type;
2160 if (code == VAR_DECL || code == PARM_DECL || code == RESULT_DECL)
2162 else if (code == FUNCTION_DECL)
2163 DECL_MODE (t) = FUNCTION_MODE;
2168 /* BLOCK nodes are used to represent the structure of binding contours
2169 and declarations, once those contours have been exited and their contents
2170 compiled. This information is used for outputting debugging info.
2171 A BLOCK may have a "controller" which is a BIND_EXPR node.
2172 Then the BLOCK is ignored unless the controller has the TREE_USED flag. */
2175 build_block (vars, tags, subblocks, supercontext, chain)
2176 tree vars, tags, subblocks, supercontext, chain;
2178 register tree block = make_node (BLOCK);
2179 BLOCK_VARS (block) = vars;
2180 BLOCK_TYPE_TAGS (block) = tags;
2181 BLOCK_SUBBLOCKS (block) = subblocks;
2182 BLOCK_SUPERCONTEXT (block) = supercontext;
2183 BLOCK_CHAIN (block) = chain;
2187 /* Return a type like TYPE except that its TYPE_READONLY is CONSTP
2188 and its TYPE_VOLATILE is VOLATILEP.
2190 Such variant types already made are recorded so that duplicates
2193 A variant types should never be used as the type of an expression.
2194 Always copy the variant information into the TREE_READONLY
2195 and TREE_THIS_VOLATILE of the expression, and then give the expression
2196 as its type the "main variant", the variant whose TYPE_READONLY
2197 and TYPE_VOLATILE are zero. Use TYPE_MAIN_VARIANT to find the
2201 build_type_variant (type, constp, volatilep)
2203 int constp, volatilep;
2205 register tree t, m = TYPE_MAIN_VARIANT (type);
2206 register struct obstack *ambient_obstack = current_obstack;
2208 /* Treat any nonzero argument as 1. */
2210 volatilep = !!volatilep;
2212 /* If not generating auxiliary info, search the chain of variants to see
2213 if there is already one there just like the one we need to have. If so,
2214 use that existing one.
2216 We don't do this in the case where we are generating aux info because
2217 in that case we want each typedef names to get it's own distinct type
2218 node, even if the type of this new typedef is the same as some other
2221 if (!flag_gen_aux_info)
2222 for (t = m; t; t = TYPE_NEXT_VARIANT (t))
2223 if (constp == TYPE_READONLY (t) && volatilep == TYPE_VOLATILE (t))
2226 /* We need a new one. */
2228 = TREE_PERMANENT (type) ? &permanent_obstack : saveable_obstack;
2230 t = copy_node (type);
2231 TYPE_READONLY (t) = constp;
2232 TYPE_VOLATILE (t) = volatilep;
2233 TYPE_POINTER_TO (t) = 0;
2234 TYPE_REFERENCE_TO (t) = 0;
2236 /* Add this type to the chain of variants of TYPE. */
2237 TYPE_NEXT_VARIANT (t) = TYPE_NEXT_VARIANT (m);
2238 TYPE_NEXT_VARIANT (m) = t;
2240 current_obstack = ambient_obstack;
2244 /* Create a new variant of TYPE, equivalent but distinct.
2245 This is so the caller can modify it. */
2248 build_type_copy (type)
2251 register tree t, m = TYPE_MAIN_VARIANT (type);
2252 register struct obstack *ambient_obstack = current_obstack;
2255 = TREE_PERMANENT (type) ? &permanent_obstack : saveable_obstack;
2257 t = copy_node (type);
2258 TYPE_POINTER_TO (t) = 0;
2259 TYPE_REFERENCE_TO (t) = 0;
2261 /* Add this type to the chain of variants of TYPE. */
2262 TYPE_NEXT_VARIANT (t) = TYPE_NEXT_VARIANT (m);
2263 TYPE_NEXT_VARIANT (m) = t;
2265 current_obstack = ambient_obstack;
2269 /* Hashing of types so that we don't make duplicates.
2270 The entry point is `type_hash_canon'. */
2272 /* Each hash table slot is a bucket containing a chain
2273 of these structures. */
2277 struct type_hash *next; /* Next structure in the bucket. */
2278 int hashcode; /* Hash code of this type. */
2279 tree type; /* The type recorded here. */
2282 /* Now here is the hash table. When recording a type, it is added
2283 to the slot whose index is the hash code mod the table size.
2284 Note that the hash table is used for several kinds of types
2285 (function types, array types and array index range types, for now).
2286 While all these live in the same table, they are completely independent,
2287 and the hash code is computed differently for each of these. */
2289 #define TYPE_HASH_SIZE 59
2290 struct type_hash *type_hash_table[TYPE_HASH_SIZE];
2292 /* Here is how primitive or already-canonicalized types' hash
2294 #define TYPE_HASH(TYPE) ((HOST_WIDE_INT) (TYPE) & 0777777)
2296 /* Compute a hash code for a list of types (chain of TREE_LIST nodes
2297 with types in the TREE_VALUE slots), by adding the hash codes
2298 of the individual types. */
2301 type_hash_list (list)
2304 register int hashcode;
2306 for (hashcode = 0, tail = list; tail; tail = TREE_CHAIN (tail))
2307 hashcode += TYPE_HASH (TREE_VALUE (tail));
2311 /* Look in the type hash table for a type isomorphic to TYPE.
2312 If one is found, return it. Otherwise return 0. */
2315 type_hash_lookup (hashcode, type)
2319 register struct type_hash *h;
2320 for (h = type_hash_table[hashcode % TYPE_HASH_SIZE]; h; h = h->next)
2321 if (h->hashcode == hashcode
2322 && TREE_CODE (h->type) == TREE_CODE (type)
2323 && TREE_TYPE (h->type) == TREE_TYPE (type)
2324 && (TYPE_MAX_VALUE (h->type) == TYPE_MAX_VALUE (type)
2325 || tree_int_cst_equal (TYPE_MAX_VALUE (h->type),
2326 TYPE_MAX_VALUE (type)))
2327 && (TYPE_MIN_VALUE (h->type) == TYPE_MIN_VALUE (type)
2328 || tree_int_cst_equal (TYPE_MIN_VALUE (h->type),
2329 TYPE_MIN_VALUE (type)))
2330 && (TYPE_DOMAIN (h->type) == TYPE_DOMAIN (type)
2331 || (TYPE_DOMAIN (h->type)
2332 && TREE_CODE (TYPE_DOMAIN (h->type)) == TREE_LIST
2333 && TYPE_DOMAIN (type)
2334 && TREE_CODE (TYPE_DOMAIN (type)) == TREE_LIST
2335 && type_list_equal (TYPE_DOMAIN (h->type), TYPE_DOMAIN (type)))))
2340 /* Add an entry to the type-hash-table
2341 for a type TYPE whose hash code is HASHCODE. */
2344 type_hash_add (hashcode, type)
2348 register struct type_hash *h;
2350 h = (struct type_hash *) oballoc (sizeof (struct type_hash));
2351 h->hashcode = hashcode;
2353 h->next = type_hash_table[hashcode % TYPE_HASH_SIZE];
2354 type_hash_table[hashcode % TYPE_HASH_SIZE] = h;
2357 /* Given TYPE, and HASHCODE its hash code, return the canonical
2358 object for an identical type if one already exists.
2359 Otherwise, return TYPE, and record it as the canonical object
2360 if it is a permanent object.
2362 To use this function, first create a type of the sort you want.
2363 Then compute its hash code from the fields of the type that
2364 make it different from other similar types.
2365 Then call this function and use the value.
2366 This function frees the type you pass in if it is a duplicate. */
2368 /* Set to 1 to debug without canonicalization. Never set by program. */
2369 int debug_no_type_hash = 0;
2372 type_hash_canon (hashcode, type)
2378 if (debug_no_type_hash)
2381 t1 = type_hash_lookup (hashcode, type);
2385 = TREE_PERMANENT (type) ? &permanent_obstack : saveable_obstack;
2386 obstack_free (o, type);
2387 #ifdef GATHER_STATISTICS
2388 tree_node_counts[(int)t_kind]--;
2389 tree_node_sizes[(int)t_kind] -= sizeof (struct tree_type);
2394 /* If this is a new type, record it for later reuse. */
2395 if (current_obstack == &permanent_obstack)
2396 type_hash_add (hashcode, type);
2401 /* Given two lists of types
2402 (chains of TREE_LIST nodes with types in the TREE_VALUE slots)
2403 return 1 if the lists contain the same types in the same order.
2404 Also, the TREE_PURPOSEs must match. */
2407 type_list_equal (l1, l2)
2410 register tree t1, t2;
2411 for (t1 = l1, t2 = l2; t1 && t2; t1 = TREE_CHAIN (t1), t2 = TREE_CHAIN (t2))
2413 if (TREE_VALUE (t1) != TREE_VALUE (t2))
2415 if (TREE_PURPOSE (t1) != TREE_PURPOSE (t2))
2417 int cmp = simple_cst_equal (TREE_PURPOSE (t1), TREE_PURPOSE (t2));
2428 /* Nonzero if integer constants T1 and T2
2429 represent the same constant value. */
2432 tree_int_cst_equal (t1, t2)
2437 if (t1 == 0 || t2 == 0)
2439 if (TREE_CODE (t1) == INTEGER_CST
2440 && TREE_CODE (t2) == INTEGER_CST
2441 && TREE_INT_CST_LOW (t1) == TREE_INT_CST_LOW (t2)
2442 && TREE_INT_CST_HIGH (t1) == TREE_INT_CST_HIGH (t2))
2447 /* Nonzero if integer constants T1 and T2 represent values that satisfy <.
2448 The precise way of comparison depends on their data type. */
2451 tree_int_cst_lt (t1, t2)
2457 if (!TREE_UNSIGNED (TREE_TYPE (t1)))
2458 return INT_CST_LT (t1, t2);
2459 return INT_CST_LT_UNSIGNED (t1, t2);
2462 /* Compare two constructor-element-type constants. */
2464 simple_cst_list_equal (l1, l2)
2467 while (l1 != NULL_TREE && l2 != NULL_TREE)
2469 int cmp = simple_cst_equal (TREE_VALUE (l1), TREE_VALUE (l2));
2474 l1 = TREE_CHAIN (l1);
2475 l2 = TREE_CHAIN (l2);
2480 /* Return truthvalue of whether T1 is the same tree structure as T2.
2481 Return 1 if they are the same.
2482 Return 0 if they are understandably different.
2483 Return -1 if either contains tree structure not understood by
2487 simple_cst_equal (t1, t2)
2490 register enum tree_code code1, code2;
2495 if (t1 == 0 || t2 == 0)
2498 code1 = TREE_CODE (t1);
2499 code2 = TREE_CODE (t2);
2501 if (code1 == NOP_EXPR || code1 == CONVERT_EXPR || code1 == NON_LVALUE_EXPR)
2502 if (code2 == NOP_EXPR || code2 == CONVERT_EXPR || code2 == NON_LVALUE_EXPR)
2503 return simple_cst_equal (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0));
2505 return simple_cst_equal (TREE_OPERAND (t1, 0), t2);
2506 else if (code2 == NOP_EXPR || code2 == CONVERT_EXPR
2507 || code2 == NON_LVALUE_EXPR)
2508 return simple_cst_equal (t1, TREE_OPERAND (t2, 0));
2516 return TREE_INT_CST_LOW (t1) == TREE_INT_CST_LOW (t2)
2517 && TREE_INT_CST_HIGH (t1) == TREE_INT_CST_HIGH (t2);
2520 return REAL_VALUES_EQUAL (TREE_REAL_CST (t1), TREE_REAL_CST (t2));
2523 return TREE_STRING_LENGTH (t1) == TREE_STRING_LENGTH (t2)
2524 && !bcmp (TREE_STRING_POINTER (t1), TREE_STRING_POINTER (t2),
2525 TREE_STRING_LENGTH (t1));
2531 return simple_cst_equal (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0));
2534 cmp = simple_cst_equal (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0));
2537 return simple_cst_list_equal (TREE_OPERAND (t1, 1), TREE_OPERAND (t2, 1));
2540 /* Special case: if either target is an unallocated VAR_DECL,
2541 it means that it's going to be unified with whatever the
2542 TARGET_EXPR is really supposed to initialize, so treat it
2543 as being equivalent to anything. */
2544 if ((TREE_CODE (TREE_OPERAND (t1, 0)) == VAR_DECL
2545 && DECL_NAME (TREE_OPERAND (t1, 0)) == NULL_TREE
2546 && DECL_RTL (TREE_OPERAND (t1, 0)) == 0)
2547 || (TREE_CODE (TREE_OPERAND (t2, 0)) == VAR_DECL
2548 && DECL_NAME (TREE_OPERAND (t2, 0)) == NULL_TREE
2549 && DECL_RTL (TREE_OPERAND (t2, 0)) == 0))
2552 cmp = simple_cst_equal (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0));
2555 return simple_cst_equal (TREE_OPERAND (t1, 1), TREE_OPERAND (t2, 1));
2557 case WITH_CLEANUP_EXPR:
2558 cmp = simple_cst_equal (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0));
2561 return simple_cst_equal (TREE_OPERAND (t1, 2), TREE_OPERAND (t1, 2));
2564 if (TREE_OPERAND (t1, 1) == TREE_OPERAND (t2, 1))
2565 return simple_cst_equal (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0));
2569 return (simple_cst_equal (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0))
2570 && simple_cst_equal (TREE_OPERAND (t1, 1), TREE_OPERAND (t2, 1))
2571 && simple_cst_equal (TREE_OPERAND (t1, 2), TREE_OPERAND (t2, 2)));
2582 case TRUNC_DIV_EXPR:
2583 case TRUNC_MOD_EXPR:
2586 cmp = simple_cst_equal (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0));
2589 return simple_cst_equal (TREE_OPERAND (t1, 1), TREE_OPERAND (t2, 1));
2593 case REFERENCE_EXPR:
2595 return simple_cst_equal (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0));
2599 return lang_simple_cst_equal (t1, t2);
2606 /* Constructors for pointer, array and function types.
2607 (RECORD_TYPE, UNION_TYPE and ENUMERAL_TYPE nodes are
2608 constructed by language-dependent code, not here.) */
2610 /* Construct, lay out and return the type of pointers to TO_TYPE.
2611 If such a type has already been constructed, reuse it. */
2614 build_pointer_type (to_type)
2617 register tree t = TYPE_POINTER_TO (to_type);
2618 register struct obstack *ambient_obstack = current_obstack;
2619 register struct obstack *ambient_saveable_obstack = saveable_obstack;
2621 /* First, if we already have a type for pointers to TO_TYPE, use it. */
2626 /* We need a new one. If TO_TYPE is permanent, make this permanent too. */
2627 if (TREE_PERMANENT (to_type))
2629 current_obstack = &permanent_obstack;
2630 saveable_obstack = &permanent_obstack;
2633 t = make_node (POINTER_TYPE);
2634 TREE_TYPE (t) = to_type;
2636 /* Record this type as the pointer to TO_TYPE. */
2637 TYPE_POINTER_TO (to_type) = t;
2639 /* Lay out the type. This function has many callers that are concerned
2640 with expression-construction, and this simplifies them all.
2641 Also, it guarantees the TYPE_SIZE is permanent if the type is. */
2644 current_obstack = ambient_obstack;
2645 saveable_obstack = ambient_saveable_obstack;
2649 /* Create a type of integers to be the TYPE_DOMAIN of an ARRAY_TYPE.
2650 MAXVAL should be the maximum value in the domain
2651 (one less than the length of the array). */
2654 build_index_type (maxval)
2657 register tree itype = make_node (INTEGER_TYPE);
2658 TYPE_PRECISION (itype) = TYPE_PRECISION (sizetype);
2659 TYPE_MIN_VALUE (itype) = build_int_2 (0, 0);
2660 TREE_TYPE (TYPE_MIN_VALUE (itype)) = sizetype;
2661 TYPE_MAX_VALUE (itype) = convert (sizetype, maxval);
2662 TYPE_MODE (itype) = TYPE_MODE (sizetype);
2663 TYPE_SIZE (itype) = TYPE_SIZE (sizetype);
2664 TYPE_ALIGN (itype) = TYPE_ALIGN (sizetype);
2665 if (TREE_CODE (maxval) == INTEGER_CST)
2667 HOST_WIDE_INT maxint = TREE_INT_CST_LOW (maxval);
2668 return type_hash_canon (maxint > 0 ? maxint : - maxint, itype);
2674 /* Just like build_index_type, but takes lowval and highval instead
2675 of just highval (maxval). */
2678 build_index_2_type (lowval,highval)
2679 tree lowval, highval;
2681 register tree itype = make_node (INTEGER_TYPE);
2682 TYPE_PRECISION (itype) = TYPE_PRECISION (sizetype);
2683 TYPE_MIN_VALUE (itype) = convert (sizetype, lowval);
2684 TYPE_MAX_VALUE (itype) = convert (sizetype, highval);
2685 TYPE_MODE (itype) = TYPE_MODE (sizetype);
2686 TYPE_SIZE (itype) = TYPE_SIZE (sizetype);
2687 TYPE_ALIGN (itype) = TYPE_ALIGN (sizetype);
2688 if ((TREE_CODE (lowval) == INTEGER_CST)
2689 && (TREE_CODE (highval) == INTEGER_CST))
2691 HOST_WIDE_INT highint = TREE_INT_CST_LOW (highval);
2692 HOST_WIDE_INT lowint = TREE_INT_CST_LOW (lowval);
2693 HOST_WIDE_INT maxint = highint - lowint;
2694 return type_hash_canon (maxint > 0 ? maxint : - maxint, itype);
2700 /* Return nonzero iff ITYPE1 and ITYPE2 are equal (in the LISP sense).
2701 Needed because when index types are not hashed, equal index types
2702 built at different times appear distinct, even though structurally,
2706 index_type_equal (itype1, itype2)
2707 tree itype1, itype2;
2709 if (TREE_CODE (itype1) != TREE_CODE (itype2))
2711 if (TREE_CODE (itype1) == INTEGER_TYPE)
2713 if (TYPE_PRECISION (itype1) != TYPE_PRECISION (itype2)
2714 || TYPE_MODE (itype1) != TYPE_MODE (itype2)
2715 || ! simple_cst_equal (TYPE_SIZE (itype1), TYPE_SIZE (itype2))
2716 || TYPE_ALIGN (itype1) != TYPE_ALIGN (itype2))
2718 if (simple_cst_equal (TYPE_MIN_VALUE (itype1), TYPE_MIN_VALUE (itype2))
2719 && simple_cst_equal (TYPE_MAX_VALUE (itype1), TYPE_MAX_VALUE (itype2)))
2725 /* Construct, lay out and return the type of arrays of elements with ELT_TYPE
2726 and number of elements specified by the range of values of INDEX_TYPE.
2727 If such a type has already been constructed, reuse it. */
2730 build_array_type (elt_type, index_type)
2731 tree elt_type, index_type;
2736 if (TREE_CODE (elt_type) == FUNCTION_TYPE)
2738 error ("arrays of functions are not meaningful");
2739 elt_type = integer_type_node;
2742 /* Make sure TYPE_POINTER_TO (elt_type) is filled in. */
2743 build_pointer_type (elt_type);
2745 /* Allocate the array after the pointer type,
2746 in case we free it in type_hash_canon. */
2747 t = make_node (ARRAY_TYPE);
2748 TREE_TYPE (t) = elt_type;
2749 TYPE_DOMAIN (t) = index_type;
2751 if (index_type == 0)
2754 hashcode = TYPE_HASH (elt_type) + TYPE_HASH (index_type);
2755 t = type_hash_canon (hashcode, t);
2757 if (TYPE_SIZE (t) == 0)
2762 /* Construct, lay out and return
2763 the type of functions returning type VALUE_TYPE
2764 given arguments of types ARG_TYPES.
2765 ARG_TYPES is a chain of TREE_LIST nodes whose TREE_VALUEs
2766 are data type nodes for the arguments of the function.
2767 If such a type has already been constructed, reuse it. */
2770 build_function_type (value_type, arg_types)
2771 tree value_type, arg_types;
2776 if (TREE_CODE (value_type) == FUNCTION_TYPE
2777 || TREE_CODE (value_type) == ARRAY_TYPE)
2779 error ("function return type cannot be function or array");
2780 value_type = integer_type_node;
2783 /* Make a node of the sort we want. */
2784 t = make_node (FUNCTION_TYPE);
2785 TREE_TYPE (t) = value_type;
2786 TYPE_ARG_TYPES (t) = arg_types;
2788 /* If we already have such a type, use the old one and free this one. */
2789 hashcode = TYPE_HASH (value_type) + type_hash_list (arg_types);
2790 t = type_hash_canon (hashcode, t);
2792 if (TYPE_SIZE (t) == 0)
2797 /* Build the node for the type of references-to-TO_TYPE. */
2800 build_reference_type (to_type)
2803 register tree t = TYPE_REFERENCE_TO (to_type);
2804 register struct obstack *ambient_obstack = current_obstack;
2805 register struct obstack *ambient_saveable_obstack = saveable_obstack;
2807 /* First, if we already have a type for pointers to TO_TYPE, use it. */
2812 /* We need a new one. If TO_TYPE is permanent, make this permanent too. */
2813 if (TREE_PERMANENT (to_type))
2815 current_obstack = &permanent_obstack;
2816 saveable_obstack = &permanent_obstack;
2819 t = make_node (REFERENCE_TYPE);
2820 TREE_TYPE (t) = to_type;
2822 /* Record this type as the pointer to TO_TYPE. */
2823 TYPE_REFERENCE_TO (to_type) = t;
2827 current_obstack = ambient_obstack;
2828 saveable_obstack = ambient_saveable_obstack;
2832 /* Construct, lay out and return the type of methods belonging to class
2833 BASETYPE and whose arguments and values are described by TYPE.
2834 If that type exists already, reuse it.
2835 TYPE must be a FUNCTION_TYPE node. */
2838 build_method_type (basetype, type)
2839 tree basetype, type;
2844 /* Make a node of the sort we want. */
2845 t = make_node (METHOD_TYPE);
2847 if (TREE_CODE (type) != FUNCTION_TYPE)
2850 TYPE_METHOD_BASETYPE (t) = TYPE_MAIN_VARIANT (basetype);
2851 TREE_TYPE (t) = TREE_TYPE (type);
2853 /* The actual arglist for this function includes a "hidden" argument
2854 which is "this". Put it into the list of argument types. */
2857 = tree_cons (NULL_TREE,
2858 build_pointer_type (basetype), TYPE_ARG_TYPES (type));
2860 /* If we already have such a type, use the old one and free this one. */
2861 hashcode = TYPE_HASH (basetype) + TYPE_HASH (type);
2862 t = type_hash_canon (hashcode, t);
2864 if (TYPE_SIZE (t) == 0)
2870 /* Construct, lay out and return the type of methods belonging to class
2871 BASETYPE and whose arguments and values are described by TYPE.
2872 If that type exists already, reuse it.
2873 TYPE must be a FUNCTION_TYPE node. */
2876 build_offset_type (basetype, type)
2877 tree basetype, type;
2882 /* Make a node of the sort we want. */
2883 t = make_node (OFFSET_TYPE);
2885 TYPE_OFFSET_BASETYPE (t) = TYPE_MAIN_VARIANT (basetype);
2886 TREE_TYPE (t) = type;
2888 /* If we already have such a type, use the old one and free this one. */
2889 hashcode = TYPE_HASH (basetype) + TYPE_HASH (type);
2890 t = type_hash_canon (hashcode, t);
2892 if (TYPE_SIZE (t) == 0)
2898 /* Create a complex type whose components are COMPONENT_TYPE. */
2901 build_complex_type (component_type)
2902 tree component_type;
2907 /* Make a node of the sort we want. */
2908 t = make_node (COMPLEX_TYPE);
2910 TREE_TYPE (t) = TYPE_MAIN_VARIANT (component_type);
2911 TYPE_VOLATILE (t) = TYPE_VOLATILE (component_type);
2912 TYPE_READONLY (t) = TYPE_READONLY (component_type);
2914 /* If we already have such a type, use the old one and free this one. */
2915 hashcode = TYPE_HASH (component_type);
2916 t = type_hash_canon (hashcode, t);
2918 if (TYPE_SIZE (t) == 0)
2924 /* Return OP, stripped of any conversions to wider types as much as is safe.
2925 Converting the value back to OP's type makes a value equivalent to OP.
2927 If FOR_TYPE is nonzero, we return a value which, if converted to
2928 type FOR_TYPE, would be equivalent to converting OP to type FOR_TYPE.
2930 If FOR_TYPE is nonzero, unaligned bit-field references may be changed to the
2931 narrowest type that can hold the value, even if they don't exactly fit.
2932 Otherwise, bit-field references are changed to a narrower type
2933 only if they can be fetched directly from memory in that type.
2935 OP must have integer, real or enumeral type. Pointers are not allowed!
2937 There are some cases where the obvious value we could return
2938 would regenerate to OP if converted to OP's type,
2939 but would not extend like OP to wider types.
2940 If FOR_TYPE indicates such extension is contemplated, we eschew such values.
2941 For example, if OP is (unsigned short)(signed char)-1,
2942 we avoid returning (signed char)-1 if FOR_TYPE is int,
2943 even though extending that to an unsigned short would regenerate OP,
2944 since the result of extending (signed char)-1 to (int)
2945 is different from (int) OP. */
2948 get_unwidened (op, for_type)
2952 /* Set UNS initially if converting OP to FOR_TYPE is a zero-extension. */
2953 /* TYPE_PRECISION is safe in place of type_precision since
2954 pointer types are not allowed. */
2955 register tree type = TREE_TYPE (op);
2956 register unsigned final_prec
2957 = TYPE_PRECISION (for_type != 0 ? for_type : type);
2959 = (for_type != 0 && for_type != type
2960 && final_prec > TYPE_PRECISION (type)
2961 && TREE_UNSIGNED (type));
2962 register tree win = op;
2964 while (TREE_CODE (op) == NOP_EXPR)
2966 register int bitschange
2967 = TYPE_PRECISION (TREE_TYPE (op))
2968 - TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (op, 0)));
2970 /* Truncations are many-one so cannot be removed.
2971 Unless we are later going to truncate down even farther. */
2973 && final_prec > TYPE_PRECISION (TREE_TYPE (op)))
2976 /* See what's inside this conversion. If we decide to strip it,
2978 op = TREE_OPERAND (op, 0);
2980 /* If we have not stripped any zero-extensions (uns is 0),
2981 we can strip any kind of extension.
2982 If we have previously stripped a zero-extension,
2983 only zero-extensions can safely be stripped.
2984 Any extension can be stripped if the bits it would produce
2985 are all going to be discarded later by truncating to FOR_TYPE. */
2989 if (! uns || final_prec <= TYPE_PRECISION (TREE_TYPE (op)))
2991 /* TREE_UNSIGNED says whether this is a zero-extension.
2992 Let's avoid computing it if it does not affect WIN
2993 and if UNS will not be needed again. */
2994 if ((uns || TREE_CODE (op) == NOP_EXPR)
2995 && TREE_UNSIGNED (TREE_TYPE (op)))
3003 if (TREE_CODE (op) == COMPONENT_REF
3004 /* Since type_for_size always gives an integer type. */
3005 && TREE_CODE (type) != REAL_TYPE)
3007 unsigned innerprec = TREE_INT_CST_LOW (DECL_SIZE (TREE_OPERAND (op, 1)));
3008 type = type_for_size (innerprec, TREE_UNSIGNED (TREE_OPERAND (op, 1)));
3010 /* We can get this structure field in the narrowest type it fits in.
3011 If FOR_TYPE is 0, do this only for a field that matches the
3012 narrower type exactly and is aligned for it
3013 The resulting extension to its nominal type (a fullword type)
3014 must fit the same conditions as for other extensions. */
3016 if (innerprec < TYPE_PRECISION (TREE_TYPE (op))
3017 && (for_type || ! DECL_BIT_FIELD (TREE_OPERAND (op, 1)))
3018 && (! uns || final_prec <= innerprec
3019 || TREE_UNSIGNED (TREE_OPERAND (op, 1)))
3022 win = build (COMPONENT_REF, type, TREE_OPERAND (op, 0),
3023 TREE_OPERAND (op, 1));
3024 TREE_SIDE_EFFECTS (win) = TREE_SIDE_EFFECTS (op);
3025 TREE_THIS_VOLATILE (win) = TREE_THIS_VOLATILE (op);
3026 TREE_RAISES (win) = TREE_RAISES (op);
3032 /* Return OP or a simpler expression for a narrower value
3033 which can be sign-extended or zero-extended to give back OP.
3034 Store in *UNSIGNEDP_PTR either 1 if the value should be zero-extended
3035 or 0 if the value should be sign-extended. */
3038 get_narrower (op, unsignedp_ptr)
3042 register int uns = 0;
3044 register tree win = op;
3046 while (TREE_CODE (op) == NOP_EXPR)
3048 register int bitschange
3049 = TYPE_PRECISION (TREE_TYPE (op))
3050 - TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (op, 0)));
3052 /* Truncations are many-one so cannot be removed. */
3056 /* See what's inside this conversion. If we decide to strip it,
3058 op = TREE_OPERAND (op, 0);
3062 /* An extension: the outermost one can be stripped,
3063 but remember whether it is zero or sign extension. */
3065 uns = TREE_UNSIGNED (TREE_TYPE (op));
3066 /* Otherwise, if a sign extension has been stripped,
3067 only sign extensions can now be stripped;
3068 if a zero extension has been stripped, only zero-extensions. */
3069 else if (uns != TREE_UNSIGNED (TREE_TYPE (op)))
3073 /* A change in nominal type can always be stripped. */
3078 if (TREE_CODE (op) == COMPONENT_REF
3079 /* Since type_for_size always gives an integer type. */
3080 && TREE_CODE (TREE_TYPE (op)) != REAL_TYPE)
3082 unsigned innerprec = TREE_INT_CST_LOW (DECL_SIZE (TREE_OPERAND (op, 1)));
3083 tree type = type_for_size (innerprec, TREE_UNSIGNED (op));
3085 /* We can get this structure field in a narrower type that fits it,
3086 but the resulting extension to its nominal type (a fullword type)
3087 must satisfy the same conditions as for other extensions.
3089 Do this only for fields that are aligned (not bit-fields),
3090 because when bit-field insns will be used there is no
3091 advantage in doing this. */
3093 if (innerprec < TYPE_PRECISION (TREE_TYPE (op))
3094 && ! DECL_BIT_FIELD (TREE_OPERAND (op, 1))
3095 && (first || uns == TREE_UNSIGNED (TREE_OPERAND (op, 1)))
3099 uns = TREE_UNSIGNED (TREE_OPERAND (op, 1));
3100 win = build (COMPONENT_REF, type, TREE_OPERAND (op, 0),
3101 TREE_OPERAND (op, 1));
3102 TREE_SIDE_EFFECTS (win) = TREE_SIDE_EFFECTS (op);
3103 TREE_THIS_VOLATILE (win) = TREE_THIS_VOLATILE (op);
3104 TREE_RAISES (win) = TREE_RAISES (op);
3107 *unsignedp_ptr = uns;
3111 /* Return the precision of a type, for arithmetic purposes.
3112 Supports all types on which arithmetic is possible
3113 (including pointer types).
3114 It's not clear yet what will be right for complex types. */
3117 type_precision (type)
3120 return ((TREE_CODE (type) == INTEGER_TYPE
3121 || TREE_CODE (type) == ENUMERAL_TYPE
3122 || TREE_CODE (type) == REAL_TYPE)
3123 ? TYPE_PRECISION (type) : POINTER_SIZE);
3126 /* Nonzero if integer constant C has a value that is permissible
3127 for type TYPE (an INTEGER_TYPE). */
3130 int_fits_type_p (c, type)
3133 if (TREE_UNSIGNED (type))
3134 return (!INT_CST_LT_UNSIGNED (TYPE_MAX_VALUE (type), c)
3135 && !INT_CST_LT_UNSIGNED (c, TYPE_MIN_VALUE (type)));
3137 return (!INT_CST_LT (TYPE_MAX_VALUE (type), c)
3138 && !INT_CST_LT (c, TYPE_MIN_VALUE (type)));
3141 /* Return the innermost context enclosing DECL that is
3142 a FUNCTION_DECL, or zero if none. */
3145 decl_function_context (decl)
3150 if (TREE_CODE (decl) == ERROR_MARK)
3153 if (TREE_CODE (decl) == SAVE_EXPR)
3154 context = SAVE_EXPR_CONTEXT (decl);
3156 context = DECL_CONTEXT (decl);
3158 while (context && TREE_CODE (context) != FUNCTION_DECL)
3160 if (TREE_CODE (context) == RECORD_TYPE
3161 || TREE_CODE (context) == UNION_TYPE)
3162 context = TYPE_CONTEXT (context);
3163 else if (TREE_CODE (context) == TYPE_DECL)
3164 context = DECL_CONTEXT (context);
3165 else if (TREE_CODE (context) == BLOCK)
3166 context = BLOCK_SUPERCONTEXT (context);
3168 /* Unhandled CONTEXT !? */
3175 /* Return the innermost context enclosing DECL that is
3176 a RECORD_TYPE or UNION_TYPE, or zero if none.
3177 TYPE_DECLs and FUNCTION_DECLs are transparent to this function. */
3180 decl_type_context (decl)
3183 tree context = DECL_CONTEXT (decl);
3187 if (TREE_CODE (context) == RECORD_TYPE
3188 || TREE_CODE (context) == UNION_TYPE)
3190 if (TREE_CODE (context) == TYPE_DECL
3191 || TREE_CODE (context) == FUNCTION_DECL)
3192 context = DECL_CONTEXT (context);
3193 else if (TREE_CODE (context) == BLOCK)
3194 context = BLOCK_SUPERCONTEXT (context);
3196 /* Unhandled CONTEXT!? */
3203 print_obstack_statistics (str, o)
3207 struct _obstack_chunk *chunk = o->chunk;
3214 n_alloc += chunk->limit - &chunk->contents[0];
3215 chunk = chunk->prev;
3217 fprintf (stderr, "obstack %s: %d bytes, %d chunks\n",
3218 str, n_alloc, n_chunks);
3221 dump_tree_statistics ()
3224 int total_nodes, total_bytes;
3226 fprintf (stderr, "\n??? tree nodes created\n\n");
3227 #ifdef GATHER_STATISTICS
3228 fprintf (stderr, "Kind Nodes Bytes\n");
3229 fprintf (stderr, "-------------------------------------\n");
3230 total_nodes = total_bytes = 0;
3231 for (i = 0; i < (int) all_kinds; i++)
3233 fprintf (stderr, "%-20s %6d %9d\n", tree_node_kind_names[i],
3234 tree_node_counts[i], tree_node_sizes[i]);
3235 total_nodes += tree_node_counts[i];
3236 total_bytes += tree_node_sizes[i];
3238 fprintf (stderr, "%-20s %9d\n", "identifier names", id_string_size);
3239 fprintf (stderr, "-------------------------------------\n");
3240 fprintf (stderr, "%-20s %6d %9d\n", "Total", total_nodes, total_bytes);
3241 fprintf (stderr, "-------------------------------------\n");
3243 fprintf (stderr, "(No per-node statistics)\n");
3245 print_lang_statistics ();