1 /* Language-independent node constructors for parse phase of GNU compiler.
2 Copyright (C) 1987, 88, 92-97, 1998 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, 59 Temple Place - Suite 330,
19 Boston, MA 02111-1307, USA. */
22 /* This file contains the low level primitives for operating on tree nodes,
23 including allocation, list operations, interning of identifiers,
24 construction of data type nodes and statement nodes,
25 and construction of type conversion nodes. It also contains
26 tables index by tree code that describe how to take apart
29 It is intended to be language-independent, but occasionally
30 calls language-dependent routines defined (for C) in typecheck.c.
32 The low-level allocation routines oballoc and permalloc
33 are used also for allocating many other kinds of objects
34 by all passes of the compiler. */
54 #ifdef NEED_DECLARATION_FREE
55 extern void free PROTO((void *));
62 #define obstack_chunk_alloc xmalloc
63 #define obstack_chunk_free free
65 /* Tree nodes of permanent duration are allocated in this obstack.
66 They are the identifier nodes, and everything outside of
67 the bodies and parameters of function definitions. */
69 struct obstack permanent_obstack;
71 /* The initial RTL, and all ..._TYPE nodes, in a function
72 are allocated in this obstack. Usually they are freed at the
73 end of the function, but if the function is inline they are saved.
74 For top-level functions, this is maybepermanent_obstack.
75 Separate obstacks are made for nested functions. */
77 struct obstack *function_maybepermanent_obstack;
79 /* This is the function_maybepermanent_obstack for top-level functions. */
81 struct obstack maybepermanent_obstack;
83 /* This is a list of function_maybepermanent_obstacks for top-level inline
84 functions that are compiled in the middle of compiling other functions. */
86 struct simple_obstack_stack *toplev_inline_obstacks;
88 /* Former elements of toplev_inline_obstacks that have been recycled. */
90 struct simple_obstack_stack *extra_inline_obstacks;
92 /* This is a list of function_maybepermanent_obstacks for inline functions
93 nested in the current function that were compiled in the middle of
94 compiling other functions. */
96 struct simple_obstack_stack *inline_obstacks;
98 /* The contents of the current function definition are allocated
99 in this obstack, and all are freed at the end of the function.
100 For top-level functions, this is temporary_obstack.
101 Separate obstacks are made for nested functions. */
103 struct obstack *function_obstack;
105 /* This is used for reading initializers of global variables. */
107 struct obstack temporary_obstack;
109 /* The tree nodes of an expression are allocated
110 in this obstack, and all are freed at the end of the expression. */
112 struct obstack momentary_obstack;
114 /* The tree nodes of a declarator are allocated
115 in this obstack, and all are freed when the declarator
118 static struct obstack temp_decl_obstack;
120 /* This points at either permanent_obstack
121 or the current function_maybepermanent_obstack. */
123 struct obstack *saveable_obstack;
125 /* This is same as saveable_obstack during parse and expansion phase;
126 it points to the current function's obstack during optimization.
127 This is the obstack to be used for creating rtl objects. */
129 struct obstack *rtl_obstack;
131 /* This points at either permanent_obstack or the current function_obstack. */
133 struct obstack *current_obstack;
135 /* This points at either permanent_obstack or the current function_obstack
136 or momentary_obstack. */
138 struct obstack *expression_obstack;
140 /* Stack of obstack selections for push_obstacks and pop_obstacks. */
144 struct obstack_stack *next;
145 struct obstack *current;
146 struct obstack *saveable;
147 struct obstack *expression;
151 struct obstack_stack *obstack_stack;
153 /* Obstack for allocating struct obstack_stack entries. */
155 static struct obstack obstack_stack_obstack;
157 /* Addresses of first objects in some obstacks.
158 This is for freeing their entire contents. */
159 char *maybepermanent_firstobj;
160 char *temporary_firstobj;
161 char *momentary_firstobj;
162 char *temp_decl_firstobj;
164 /* This is used to preserve objects (mainly array initializers) that need to
165 live until the end of the current function, but no further. */
166 char *momentary_function_firstobj;
168 /* Nonzero means all ..._TYPE nodes should be allocated permanently. */
170 int all_types_permanent;
172 /* Stack of places to restore the momentary obstack back to. */
174 struct momentary_level
176 /* Pointer back to previous such level. */
177 struct momentary_level *prev;
178 /* First object allocated within this level. */
180 /* Value of expression_obstack saved at entry to this level. */
181 struct obstack *obstack;
184 struct momentary_level *momentary_stack;
186 /* Table indexed by tree code giving a string containing a character
187 classifying the tree code. Possibilities are
188 t, d, s, c, r, <, 1, 2 and e. See tree.def for details. */
190 #define DEFTREECODE(SYM, NAME, TYPE, LENGTH) TYPE,
192 char tree_code_type[MAX_TREE_CODES] = {
197 /* Table indexed by tree code giving number of expression
198 operands beyond the fixed part of the node structure.
199 Not used for types or decls. */
201 #define DEFTREECODE(SYM, NAME, TYPE, LENGTH) LENGTH,
203 int tree_code_length[MAX_TREE_CODES] = {
208 /* Names of tree components.
209 Used for printing out the tree and error messages. */
210 #define DEFTREECODE(SYM, NAME, TYPE, LEN) NAME,
212 char *tree_code_name[MAX_TREE_CODES] = {
217 /* Statistics-gathering stuff. */
238 int tree_node_counts[(int)all_kinds];
239 int tree_node_sizes[(int)all_kinds];
240 int id_string_size = 0;
242 char *tree_node_kind_names[] = {
260 /* Hash table for uniquizing IDENTIFIER_NODEs by name. */
262 #define MAX_HASH_TABLE 1009
263 static tree hash_table[MAX_HASH_TABLE]; /* id hash buckets */
265 /* 0 while creating built-in identifiers. */
266 static int do_identifier_warnings;
268 /* Unique id for next decl created. */
269 static int next_decl_uid;
270 /* Unique id for next type created. */
271 static int next_type_uid = 1;
273 /* Here is how primitive or already-canonicalized types' hash
275 #define TYPE_HASH(TYPE) ((unsigned long) (TYPE) & 0777777)
277 extern char *mode_name[];
279 void gcc_obstack_init ();
281 /* Init the principal obstacks. */
286 gcc_obstack_init (&obstack_stack_obstack);
287 gcc_obstack_init (&permanent_obstack);
289 gcc_obstack_init (&temporary_obstack);
290 temporary_firstobj = (char *) obstack_alloc (&temporary_obstack, 0);
291 gcc_obstack_init (&momentary_obstack);
292 momentary_firstobj = (char *) obstack_alloc (&momentary_obstack, 0);
293 momentary_function_firstobj = momentary_firstobj;
294 gcc_obstack_init (&maybepermanent_obstack);
295 maybepermanent_firstobj
296 = (char *) obstack_alloc (&maybepermanent_obstack, 0);
297 gcc_obstack_init (&temp_decl_obstack);
298 temp_decl_firstobj = (char *) obstack_alloc (&temp_decl_obstack, 0);
300 function_obstack = &temporary_obstack;
301 function_maybepermanent_obstack = &maybepermanent_obstack;
302 current_obstack = &permanent_obstack;
303 expression_obstack = &permanent_obstack;
304 rtl_obstack = saveable_obstack = &permanent_obstack;
306 /* Init the hash table of identifiers. */
307 bzero ((char *) hash_table, sizeof hash_table);
311 gcc_obstack_init (obstack)
312 struct obstack *obstack;
314 /* Let particular systems override the size of a chunk. */
315 #ifndef OBSTACK_CHUNK_SIZE
316 #define OBSTACK_CHUNK_SIZE 0
318 /* Let them override the alloc and free routines too. */
319 #ifndef OBSTACK_CHUNK_ALLOC
320 #define OBSTACK_CHUNK_ALLOC xmalloc
322 #ifndef OBSTACK_CHUNK_FREE
323 #define OBSTACK_CHUNK_FREE free
325 _obstack_begin (obstack, OBSTACK_CHUNK_SIZE, 0,
326 (void *(*) ()) OBSTACK_CHUNK_ALLOC,
327 (void (*) ()) OBSTACK_CHUNK_FREE);
330 /* Save all variables describing the current status into the structure *P.
331 This is used before starting a nested function.
333 CONTEXT is the decl_function_context for the function we're about to
334 compile; if it isn't current_function_decl, we have to play some games. */
337 save_tree_status (p, context)
341 p->all_types_permanent = all_types_permanent;
342 p->momentary_stack = momentary_stack;
343 p->maybepermanent_firstobj = maybepermanent_firstobj;
344 p->temporary_firstobj = temporary_firstobj;
345 p->momentary_firstobj = momentary_firstobj;
346 p->momentary_function_firstobj = momentary_function_firstobj;
347 p->function_obstack = function_obstack;
348 p->function_maybepermanent_obstack = function_maybepermanent_obstack;
349 p->current_obstack = current_obstack;
350 p->expression_obstack = expression_obstack;
351 p->saveable_obstack = saveable_obstack;
352 p->rtl_obstack = rtl_obstack;
353 p->inline_obstacks = inline_obstacks;
355 if (context == current_function_decl)
356 /* Objects that need to be saved in this function can be in the nonsaved
357 obstack of the enclosing function since they can't possibly be needed
358 once it has returned. */
359 function_maybepermanent_obstack = function_obstack;
362 /* We're compiling a function which isn't nested in the current
363 function. We need to create a new maybepermanent_obstack for this
364 function, since it can't go onto any of the existing obstacks. */
365 struct simple_obstack_stack **head;
366 struct simple_obstack_stack *current;
368 if (context == NULL_TREE)
369 head = &toplev_inline_obstacks;
372 struct function *f = find_function_data (context);
373 head = &f->inline_obstacks;
376 if (context == NULL_TREE && extra_inline_obstacks)
378 current = extra_inline_obstacks;
379 extra_inline_obstacks = current->next;
383 current = ((struct simple_obstack_stack *)
384 xmalloc (sizeof (struct simple_obstack_stack)));
387 = (struct obstack *) xmalloc (sizeof (struct obstack));
388 gcc_obstack_init (current->obstack);
391 function_maybepermanent_obstack = current->obstack;
393 current->next = *head;
397 maybepermanent_firstobj
398 = (char *) obstack_finish (function_maybepermanent_obstack);
400 function_obstack = (struct obstack *) xmalloc (sizeof (struct obstack));
401 gcc_obstack_init (function_obstack);
403 current_obstack = &permanent_obstack;
404 expression_obstack = &permanent_obstack;
405 rtl_obstack = saveable_obstack = &permanent_obstack;
407 temporary_firstobj = (char *) obstack_alloc (&temporary_obstack, 0);
408 momentary_firstobj = (char *) obstack_finish (&momentary_obstack);
409 momentary_function_firstobj = momentary_firstobj;
412 /* Restore all variables describing the current status from the structure *P.
413 This is used after a nested function. */
416 restore_tree_status (p, context)
420 all_types_permanent = p->all_types_permanent;
421 momentary_stack = p->momentary_stack;
423 obstack_free (&momentary_obstack, momentary_function_firstobj);
425 /* Free saveable storage used by the function just compiled and not
428 CAUTION: This is in function_obstack of the containing function.
429 So we must be sure that we never allocate from that obstack during
430 the compilation of a nested function if we expect it to survive
431 past the nested function's end. */
432 obstack_free (function_maybepermanent_obstack, maybepermanent_firstobj);
434 /* If we were compiling a toplevel function, we can free this space now. */
435 if (context == NULL_TREE)
437 obstack_free (&temporary_obstack, temporary_firstobj);
438 obstack_free (&momentary_obstack, momentary_function_firstobj);
441 /* If we were compiling a toplevel function that we don't actually want
442 to save anything from, return the obstack to the pool. */
443 if (context == NULL_TREE
444 && obstack_empty_p (function_maybepermanent_obstack))
446 struct simple_obstack_stack *current, **p = &toplev_inline_obstacks;
450 while ((*p)->obstack != function_maybepermanent_obstack)
455 current->next = extra_inline_obstacks;
456 extra_inline_obstacks = current;
460 obstack_free (function_obstack, 0);
461 free (function_obstack);
463 temporary_firstobj = p->temporary_firstobj;
464 momentary_firstobj = p->momentary_firstobj;
465 momentary_function_firstobj = p->momentary_function_firstobj;
466 maybepermanent_firstobj = p->maybepermanent_firstobj;
467 function_obstack = p->function_obstack;
468 function_maybepermanent_obstack = p->function_maybepermanent_obstack;
469 current_obstack = p->current_obstack;
470 expression_obstack = p->expression_obstack;
471 saveable_obstack = p->saveable_obstack;
472 rtl_obstack = p->rtl_obstack;
473 inline_obstacks = p->inline_obstacks;
476 /* Start allocating on the temporary (per function) obstack.
477 This is done in start_function before parsing the function body,
478 and before each initialization at top level, and to go back
479 to temporary allocation after doing permanent_allocation. */
482 temporary_allocation ()
484 /* Note that function_obstack at top level points to temporary_obstack.
485 But within a nested function context, it is a separate obstack. */
486 current_obstack = function_obstack;
487 expression_obstack = function_obstack;
488 rtl_obstack = saveable_obstack = function_maybepermanent_obstack;
493 /* Start allocating on the permanent obstack but don't
494 free the temporary data. After calling this, call
495 `permanent_allocation' to fully resume permanent allocation status. */
498 end_temporary_allocation ()
500 current_obstack = &permanent_obstack;
501 expression_obstack = &permanent_obstack;
502 rtl_obstack = saveable_obstack = &permanent_obstack;
505 /* Resume allocating on the temporary obstack, undoing
506 effects of `end_temporary_allocation'. */
509 resume_temporary_allocation ()
511 current_obstack = function_obstack;
512 expression_obstack = function_obstack;
513 rtl_obstack = saveable_obstack = function_maybepermanent_obstack;
516 /* While doing temporary allocation, switch to allocating in such a
517 way as to save all nodes if the function is inlined. Call
518 resume_temporary_allocation to go back to ordinary temporary
522 saveable_allocation ()
524 /* Note that function_obstack at top level points to temporary_obstack.
525 But within a nested function context, it is a separate obstack. */
526 expression_obstack = current_obstack = saveable_obstack;
529 /* Switch to current obstack CURRENT and maybepermanent obstack SAVEABLE,
530 recording the previously current obstacks on a stack.
531 This does not free any storage in any obstack. */
534 push_obstacks (current, saveable)
535 struct obstack *current, *saveable;
537 struct obstack_stack *p
538 = (struct obstack_stack *) obstack_alloc (&obstack_stack_obstack,
539 (sizeof (struct obstack_stack)));
541 p->current = current_obstack;
542 p->saveable = saveable_obstack;
543 p->expression = expression_obstack;
544 p->rtl = rtl_obstack;
545 p->next = obstack_stack;
548 current_obstack = current;
549 expression_obstack = current;
550 rtl_obstack = saveable_obstack = saveable;
553 /* Save the current set of obstacks, but don't change them. */
556 push_obstacks_nochange ()
558 struct obstack_stack *p
559 = (struct obstack_stack *) obstack_alloc (&obstack_stack_obstack,
560 (sizeof (struct obstack_stack)));
562 p->current = current_obstack;
563 p->saveable = saveable_obstack;
564 p->expression = expression_obstack;
565 p->rtl = rtl_obstack;
566 p->next = obstack_stack;
570 /* Pop the obstack selection stack. */
575 struct obstack_stack *p = obstack_stack;
576 obstack_stack = p->next;
578 current_obstack = p->current;
579 saveable_obstack = p->saveable;
580 expression_obstack = p->expression;
581 rtl_obstack = p->rtl;
583 obstack_free (&obstack_stack_obstack, p);
586 /* Nonzero if temporary allocation is currently in effect.
587 Zero if currently doing permanent allocation. */
590 allocation_temporary_p ()
592 return current_obstack != &permanent_obstack;
595 /* Go back to allocating on the permanent obstack
596 and free everything in the temporary obstack.
598 FUNCTION_END is true only if we have just finished compiling a function.
599 In that case, we also free preserved initial values on the momentary
603 permanent_allocation (function_end)
606 /* Free up previous temporary obstack data */
607 obstack_free (&temporary_obstack, temporary_firstobj);
610 obstack_free (&momentary_obstack, momentary_function_firstobj);
611 momentary_firstobj = momentary_function_firstobj;
614 obstack_free (&momentary_obstack, momentary_firstobj);
615 obstack_free (function_maybepermanent_obstack, maybepermanent_firstobj);
616 obstack_free (&temp_decl_obstack, temp_decl_firstobj);
618 /* Free up the maybepermanent_obstacks for any of our nested functions
619 which were compiled at a lower level. */
620 while (inline_obstacks)
622 struct simple_obstack_stack *current = inline_obstacks;
623 inline_obstacks = current->next;
624 obstack_free (current->obstack, 0);
625 free (current->obstack);
629 current_obstack = &permanent_obstack;
630 expression_obstack = &permanent_obstack;
631 rtl_obstack = saveable_obstack = &permanent_obstack;
634 /* Save permanently everything on the maybepermanent_obstack. */
639 maybepermanent_firstobj
640 = (char *) obstack_alloc (function_maybepermanent_obstack, 0);
644 preserve_initializer ()
646 struct momentary_level *tem;
650 = (char *) obstack_alloc (&temporary_obstack, 0);
651 maybepermanent_firstobj
652 = (char *) obstack_alloc (function_maybepermanent_obstack, 0);
654 old_momentary = momentary_firstobj;
656 = (char *) obstack_alloc (&momentary_obstack, 0);
657 if (momentary_firstobj != old_momentary)
658 for (tem = momentary_stack; tem; tem = tem->prev)
659 tem->base = momentary_firstobj;
662 /* Start allocating new rtl in current_obstack.
663 Use resume_temporary_allocation
664 to go back to allocating rtl in saveable_obstack. */
667 rtl_in_current_obstack ()
669 rtl_obstack = current_obstack;
672 /* Start allocating rtl from saveable_obstack. Intended to be used after
673 a call to push_obstacks_nochange. */
676 rtl_in_saveable_obstack ()
678 rtl_obstack = saveable_obstack;
681 /* Allocate SIZE bytes in the current obstack
682 and return a pointer to them.
683 In practice the current obstack is always the temporary one. */
689 return (char *) obstack_alloc (current_obstack, size);
692 /* Free the object PTR in the current obstack
693 as well as everything allocated since PTR.
694 In practice the current obstack is always the temporary one. */
700 obstack_free (current_obstack, ptr);
703 /* Allocate SIZE bytes in the permanent obstack
704 and return a pointer to them. */
710 return (char *) obstack_alloc (&permanent_obstack, size);
713 /* Allocate NELEM items of SIZE bytes in the permanent obstack
714 and return a pointer to them. The storage is cleared before
715 returning the value. */
718 perm_calloc (nelem, size)
722 char *rval = (char *) obstack_alloc (&permanent_obstack, nelem * size);
723 bzero (rval, nelem * size);
727 /* Allocate SIZE bytes in the saveable obstack
728 and return a pointer to them. */
734 return (char *) obstack_alloc (saveable_obstack, size);
737 /* Allocate SIZE bytes in the expression obstack
738 and return a pointer to them. */
744 return (char *) obstack_alloc (expression_obstack, size);
747 /* Print out which obstack an object is in. */
750 print_obstack_name (object, file, prefix)
755 struct obstack *obstack = NULL;
756 char *obstack_name = NULL;
759 for (p = outer_function_chain; p; p = p->next)
761 if (_obstack_allocated_p (p->function_obstack, object))
763 obstack = p->function_obstack;
764 obstack_name = "containing function obstack";
766 if (_obstack_allocated_p (p->function_maybepermanent_obstack, object))
768 obstack = p->function_maybepermanent_obstack;
769 obstack_name = "containing function maybepermanent obstack";
773 if (_obstack_allocated_p (&obstack_stack_obstack, object))
775 obstack = &obstack_stack_obstack;
776 obstack_name = "obstack_stack_obstack";
778 else if (_obstack_allocated_p (function_obstack, object))
780 obstack = function_obstack;
781 obstack_name = "function obstack";
783 else if (_obstack_allocated_p (&permanent_obstack, object))
785 obstack = &permanent_obstack;
786 obstack_name = "permanent_obstack";
788 else if (_obstack_allocated_p (&momentary_obstack, object))
790 obstack = &momentary_obstack;
791 obstack_name = "momentary_obstack";
793 else if (_obstack_allocated_p (function_maybepermanent_obstack, object))
795 obstack = function_maybepermanent_obstack;
796 obstack_name = "function maybepermanent obstack";
798 else if (_obstack_allocated_p (&temp_decl_obstack, object))
800 obstack = &temp_decl_obstack;
801 obstack_name = "temp_decl_obstack";
804 /* Check to see if the object is in the free area of the obstack. */
807 if (object >= obstack->next_free
808 && object < obstack->chunk_limit)
809 fprintf (file, "%s in free portion of obstack %s",
810 prefix, obstack_name);
812 fprintf (file, "%s allocated from %s", prefix, obstack_name);
815 fprintf (file, "%s not allocated from any obstack", prefix);
819 debug_obstack (object)
822 print_obstack_name (object, stderr, "object");
823 fprintf (stderr, ".\n");
826 /* Return 1 if OBJ is in the permanent obstack.
827 This is slow, and should be used only for debugging.
828 Use TREE_PERMANENT for other purposes. */
831 object_permanent_p (obj)
834 return _obstack_allocated_p (&permanent_obstack, obj);
837 /* Start a level of momentary allocation.
838 In C, each compound statement has its own level
839 and that level is freed at the end of each statement.
840 All expression nodes are allocated in the momentary allocation level. */
845 struct momentary_level *tem
846 = (struct momentary_level *) obstack_alloc (&momentary_obstack,
847 sizeof (struct momentary_level));
848 tem->prev = momentary_stack;
849 tem->base = (char *) obstack_base (&momentary_obstack);
850 tem->obstack = expression_obstack;
851 momentary_stack = tem;
852 expression_obstack = &momentary_obstack;
855 /* Set things up so the next clear_momentary will only clear memory
856 past our present position in momentary_obstack. */
859 preserve_momentary ()
861 momentary_stack->base = (char *) obstack_base (&momentary_obstack);
864 /* Free all the storage in the current momentary-allocation level.
865 In C, this happens at the end of each statement. */
870 obstack_free (&momentary_obstack, momentary_stack->base);
873 /* Discard a level of momentary allocation.
874 In C, this happens at the end of each compound statement.
875 Restore the status of expression node allocation
876 that was in effect before this level was created. */
881 struct momentary_level *tem = momentary_stack;
882 momentary_stack = tem->prev;
883 expression_obstack = tem->obstack;
884 /* We can't free TEM from the momentary_obstack, because there might
885 be objects above it which have been saved. We can free back to the
886 stack of the level we are popping off though. */
887 obstack_free (&momentary_obstack, tem->base);
890 /* Pop back to the previous level of momentary allocation,
891 but don't free any momentary data just yet. */
894 pop_momentary_nofree ()
896 struct momentary_level *tem = momentary_stack;
897 momentary_stack = tem->prev;
898 expression_obstack = tem->obstack;
901 /* Call when starting to parse a declaration:
902 make expressions in the declaration last the length of the function.
903 Returns an argument that should be passed to resume_momentary later. */
908 register int tem = expression_obstack == &momentary_obstack;
909 expression_obstack = saveable_obstack;
913 /* Call when finished parsing a declaration:
914 restore the treatment of node-allocation that was
915 in effect before the suspension.
916 YES should be the value previously returned by suspend_momentary. */
919 resume_momentary (yes)
923 expression_obstack = &momentary_obstack;
926 /* Init the tables indexed by tree code.
927 Note that languages can add to these tables to define their own codes. */
935 /* Return a newly allocated node of code CODE.
936 Initialize the node's unique id and its TREE_PERMANENT flag.
937 For decl and type nodes, some other fields are initialized.
938 The rest of the node is initialized to zero.
940 Achoo! I got a code in the node. */
947 register int type = TREE_CODE_CLASS (code);
949 register struct obstack *obstack = current_obstack;
951 #ifdef GATHER_STATISTICS
952 register tree_node_kind kind;
957 case 'd': /* A decl node */
958 #ifdef GATHER_STATISTICS
961 length = sizeof (struct tree_decl);
962 /* All decls in an inline function need to be saved. */
963 if (obstack != &permanent_obstack)
964 obstack = saveable_obstack;
966 /* PARM_DECLs go on the context of the parent. If this is a nested
967 function, then we must allocate the PARM_DECL on the parent's
968 obstack, so that they will live to the end of the parent's
969 closing brace. This is necessary in case we try to inline the
970 function into its parent.
972 PARM_DECLs of top-level functions do not have this problem. However,
973 we allocate them where we put the FUNCTION_DECL for languages such as
974 Ada that need to consult some flags in the PARM_DECLs of the function
977 See comment in restore_tree_status for why we can't put this
978 in function_obstack. */
979 if (code == PARM_DECL && obstack != &permanent_obstack)
982 if (current_function_decl)
983 context = decl_function_context (current_function_decl);
987 = find_function_data (context)->function_maybepermanent_obstack;
991 case 't': /* a type node */
992 #ifdef GATHER_STATISTICS
995 length = sizeof (struct tree_type);
996 /* All data types are put where we can preserve them if nec. */
997 if (obstack != &permanent_obstack)
998 obstack = all_types_permanent ? &permanent_obstack : saveable_obstack;
1001 case 'b': /* a lexical block */
1002 #ifdef GATHER_STATISTICS
1005 length = sizeof (struct tree_block);
1006 /* All BLOCK nodes are put where we can preserve them if nec. */
1007 if (obstack != &permanent_obstack)
1008 obstack = saveable_obstack;
1011 case 's': /* an expression with side effects */
1012 #ifdef GATHER_STATISTICS
1016 case 'r': /* a reference */
1017 #ifdef GATHER_STATISTICS
1021 case 'e': /* an expression */
1022 case '<': /* a comparison expression */
1023 case '1': /* a unary arithmetic expression */
1024 case '2': /* a binary arithmetic expression */
1025 #ifdef GATHER_STATISTICS
1029 obstack = expression_obstack;
1030 /* All BIND_EXPR nodes are put where we can preserve them if nec. */
1031 if (code == BIND_EXPR && obstack != &permanent_obstack)
1032 obstack = saveable_obstack;
1033 length = sizeof (struct tree_exp)
1034 + (tree_code_length[(int) code] - 1) * sizeof (char *);
1037 case 'c': /* a constant */
1038 #ifdef GATHER_STATISTICS
1041 obstack = expression_obstack;
1043 /* We can't use tree_code_length for INTEGER_CST, since the number of
1044 words is machine-dependent due to varying length of HOST_WIDE_INT,
1045 which might be wider than a pointer (e.g., long long). Similarly
1046 for REAL_CST, since the number of words is machine-dependent due
1047 to varying size and alignment of `double'. */
1049 if (code == INTEGER_CST)
1050 length = sizeof (struct tree_int_cst);
1051 else if (code == REAL_CST)
1052 length = sizeof (struct tree_real_cst);
1054 length = sizeof (struct tree_common)
1055 + tree_code_length[(int) code] * sizeof (char *);
1058 case 'x': /* something random, like an identifier. */
1059 #ifdef GATHER_STATISTICS
1060 if (code == IDENTIFIER_NODE)
1062 else if (code == OP_IDENTIFIER)
1064 else if (code == TREE_VEC)
1069 length = sizeof (struct tree_common)
1070 + tree_code_length[(int) code] * sizeof (char *);
1071 /* Identifier nodes are always permanent since they are
1072 unique in a compiler run. */
1073 if (code == IDENTIFIER_NODE) obstack = &permanent_obstack;
1080 t = (tree) obstack_alloc (obstack, length);
1082 #ifdef GATHER_STATISTICS
1083 tree_node_counts[(int)kind]++;
1084 tree_node_sizes[(int)kind] += length;
1087 /* Clear a word at a time. */
1088 for (i = (length / sizeof (int)) - 1; i >= 0; i--)
1090 /* Clear any extra bytes. */
1091 for (i = length / sizeof (int) * sizeof (int); i < length; i++)
1092 ((char *) t)[i] = 0;
1094 TREE_SET_CODE (t, code);
1095 if (obstack == &permanent_obstack)
1096 TREE_PERMANENT (t) = 1;
1101 TREE_SIDE_EFFECTS (t) = 1;
1102 TREE_TYPE (t) = void_type_node;
1106 if (code != FUNCTION_DECL)
1108 DECL_IN_SYSTEM_HEADER (t)
1109 = in_system_header && (obstack == &permanent_obstack);
1110 DECL_SOURCE_LINE (t) = lineno;
1111 DECL_SOURCE_FILE (t) = (input_filename) ? input_filename : "<built-in>";
1112 DECL_UID (t) = next_decl_uid++;
1116 TYPE_UID (t) = next_type_uid++;
1118 TYPE_MAIN_VARIANT (t) = t;
1119 TYPE_OBSTACK (t) = obstack;
1120 TYPE_ATTRIBUTES (t) = NULL_TREE;
1121 #ifdef SET_DEFAULT_TYPE_ATTRIBUTES
1122 SET_DEFAULT_TYPE_ATTRIBUTES (t);
1127 TREE_CONSTANT (t) = 1;
1134 /* Return a new node with the same contents as NODE
1135 except that its TREE_CHAIN is zero and it has a fresh uid. */
1142 register enum tree_code code = TREE_CODE (node);
1143 register int length;
1146 switch (TREE_CODE_CLASS (code))
1148 case 'd': /* A decl node */
1149 length = sizeof (struct tree_decl);
1152 case 't': /* a type node */
1153 length = sizeof (struct tree_type);
1156 case 'b': /* a lexical block node */
1157 length = sizeof (struct tree_block);
1160 case 'r': /* a reference */
1161 case 'e': /* an expression */
1162 case 's': /* an expression with side effects */
1163 case '<': /* a comparison expression */
1164 case '1': /* a unary arithmetic expression */
1165 case '2': /* a binary arithmetic expression */
1166 length = sizeof (struct tree_exp)
1167 + (tree_code_length[(int) code] - 1) * sizeof (char *);
1170 case 'c': /* a constant */
1171 /* We can't use tree_code_length for INTEGER_CST, since the number of
1172 words is machine-dependent due to varying length of HOST_WIDE_INT,
1173 which might be wider than a pointer (e.g., long long). Similarly
1174 for REAL_CST, since the number of words is machine-dependent due
1175 to varying size and alignment of `double'. */
1176 if (code == INTEGER_CST)
1177 length = sizeof (struct tree_int_cst);
1178 else if (code == REAL_CST)
1179 length = sizeof (struct tree_real_cst);
1181 length = (sizeof (struct tree_common)
1182 + tree_code_length[(int) code] * sizeof (char *));
1185 case 'x': /* something random, like an identifier. */
1186 length = sizeof (struct tree_common)
1187 + tree_code_length[(int) code] * sizeof (char *);
1188 if (code == TREE_VEC)
1189 length += (TREE_VEC_LENGTH (node) - 1) * sizeof (char *);
1192 t = (tree) obstack_alloc (current_obstack, length);
1194 for (i = (length / sizeof (int)) - 1; i >= 0; i--)
1195 ((int *) t)[i] = ((int *) node)[i];
1196 /* Clear any extra bytes. */
1197 for (i = length / sizeof (int) * sizeof (int); i < length; i++)
1198 ((char *) t)[i] = ((char *) node)[i];
1201 TREE_ASM_WRITTEN (t) = 0;
1203 if (TREE_CODE_CLASS (code) == 'd')
1204 DECL_UID (t) = next_decl_uid++;
1205 else if (TREE_CODE_CLASS (code) == 't')
1207 TYPE_UID (t) = next_type_uid++;
1208 TYPE_OBSTACK (t) = current_obstack;
1210 /* The following is so that the debug code for
1211 the copy is different from the original type.
1212 The two statements usually duplicate each other
1213 (because they clear fields of the same union),
1214 but the optimizer should catch that. */
1215 TYPE_SYMTAB_POINTER (t) = 0;
1216 TYPE_SYMTAB_ADDRESS (t) = 0;
1219 TREE_PERMANENT (t) = (current_obstack == &permanent_obstack);
1224 /* Return a copy of a chain of nodes, chained through the TREE_CHAIN field.
1225 For example, this can copy a list made of TREE_LIST nodes. */
1232 register tree prev, next;
1237 head = prev = copy_node (list);
1238 next = TREE_CHAIN (list);
1241 TREE_CHAIN (prev) = copy_node (next);
1242 prev = TREE_CHAIN (prev);
1243 next = TREE_CHAIN (next);
1250 /* Return an IDENTIFIER_NODE whose name is TEXT (a null-terminated string).
1251 If an identifier with that name has previously been referred to,
1252 the same node is returned this time. */
1255 get_identifier (text)
1256 register char *text;
1261 register int len, hash_len;
1263 /* Compute length of text in len. */
1264 for (len = 0; text[len]; len++);
1266 /* Decide how much of that length to hash on */
1268 if (warn_id_clash && len > id_clash_len)
1269 hash_len = id_clash_len;
1271 /* Compute hash code */
1272 hi = hash_len * 613 + (unsigned) text[0];
1273 for (i = 1; i < hash_len; i += 2)
1274 hi = ((hi * 613) + (unsigned) (text[i]));
1276 hi &= (1 << HASHBITS) - 1;
1277 hi %= MAX_HASH_TABLE;
1279 /* Search table for identifier */
1280 for (idp = hash_table[hi]; idp; idp = TREE_CHAIN (idp))
1281 if (IDENTIFIER_LENGTH (idp) == len
1282 && IDENTIFIER_POINTER (idp)[0] == text[0]
1283 && !bcmp (IDENTIFIER_POINTER (idp), text, len))
1284 return idp; /* <-- return if found */
1286 /* Not found; optionally warn about a similar identifier */
1287 if (warn_id_clash && do_identifier_warnings && len >= id_clash_len)
1288 for (idp = hash_table[hi]; idp; idp = TREE_CHAIN (idp))
1289 if (!strncmp (IDENTIFIER_POINTER (idp), text, id_clash_len))
1291 warning ("`%s' and `%s' identical in first %d characters",
1292 IDENTIFIER_POINTER (idp), text, id_clash_len);
1296 if (tree_code_length[(int) IDENTIFIER_NODE] < 0)
1297 abort (); /* set_identifier_size hasn't been called. */
1299 /* Not found, create one, add to chain */
1300 idp = make_node (IDENTIFIER_NODE);
1301 IDENTIFIER_LENGTH (idp) = len;
1302 #ifdef GATHER_STATISTICS
1303 id_string_size += len;
1306 IDENTIFIER_POINTER (idp) = obstack_copy0 (&permanent_obstack, text, len);
1308 TREE_CHAIN (idp) = hash_table[hi];
1309 hash_table[hi] = idp;
1310 return idp; /* <-- return if created */
1313 /* If an identifier with the name TEXT (a null-terminated string) has
1314 previously been referred to, return that node; otherwise return
1318 maybe_get_identifier (text)
1319 register char *text;
1324 register int len, hash_len;
1326 /* Compute length of text in len. */
1327 for (len = 0; text[len]; len++);
1329 /* Decide how much of that length to hash on */
1331 if (warn_id_clash && len > id_clash_len)
1332 hash_len = id_clash_len;
1334 /* Compute hash code */
1335 hi = hash_len * 613 + (unsigned) text[0];
1336 for (i = 1; i < hash_len; i += 2)
1337 hi = ((hi * 613) + (unsigned) (text[i]));
1339 hi &= (1 << HASHBITS) - 1;
1340 hi %= MAX_HASH_TABLE;
1342 /* Search table for identifier */
1343 for (idp = hash_table[hi]; idp; idp = TREE_CHAIN (idp))
1344 if (IDENTIFIER_LENGTH (idp) == len
1345 && IDENTIFIER_POINTER (idp)[0] == text[0]
1346 && !bcmp (IDENTIFIER_POINTER (idp), text, len))
1347 return idp; /* <-- return if found */
1352 /* Enable warnings on similar identifiers (if requested).
1353 Done after the built-in identifiers are created. */
1356 start_identifier_warnings ()
1358 do_identifier_warnings = 1;
1361 /* Record the size of an identifier node for the language in use.
1362 SIZE is the total size in bytes.
1363 This is called by the language-specific files. This must be
1364 called before allocating any identifiers. */
1367 set_identifier_size (size)
1370 tree_code_length[(int) IDENTIFIER_NODE]
1371 = (size - sizeof (struct tree_common)) / sizeof (tree);
1374 /* Return a newly constructed INTEGER_CST node whose constant value
1375 is specified by the two ints LOW and HI.
1376 The TREE_TYPE is set to `int'.
1378 This function should be used via the `build_int_2' macro. */
1381 build_int_2_wide (low, hi)
1382 HOST_WIDE_INT low, hi;
1384 register tree t = make_node (INTEGER_CST);
1385 TREE_INT_CST_LOW (t) = low;
1386 TREE_INT_CST_HIGH (t) = hi;
1387 TREE_TYPE (t) = integer_type_node;
1391 /* Return a new REAL_CST node whose type is TYPE and value is D. */
1394 build_real (type, d)
1401 /* Check for valid float value for this type on this target machine;
1402 if not, can print error message and store a valid value in D. */
1403 #ifdef CHECK_FLOAT_VALUE
1404 CHECK_FLOAT_VALUE (TYPE_MODE (type), d, overflow);
1407 v = make_node (REAL_CST);
1408 TREE_TYPE (v) = type;
1409 TREE_REAL_CST (v) = d;
1410 TREE_OVERFLOW (v) = TREE_CONSTANT_OVERFLOW (v) = overflow;
1414 /* Return a new REAL_CST node whose type is TYPE
1415 and whose value is the integer value of the INTEGER_CST node I. */
1417 #if !defined (REAL_IS_NOT_DOUBLE) || defined (REAL_ARITHMETIC)
1420 real_value_from_int_cst (type, i)
1425 #ifdef REAL_ARITHMETIC
1426 if (! TREE_UNSIGNED (TREE_TYPE (i)))
1427 REAL_VALUE_FROM_INT (d, TREE_INT_CST_LOW (i), TREE_INT_CST_HIGH (i),
1430 REAL_VALUE_FROM_UNSIGNED_INT (d, TREE_INT_CST_LOW (i),
1431 TREE_INT_CST_HIGH (i), TYPE_MODE (type));
1432 #else /* not REAL_ARITHMETIC */
1433 /* Some 386 compilers mishandle unsigned int to float conversions,
1434 so introduce a temporary variable E to avoid those bugs. */
1435 if (TREE_INT_CST_HIGH (i) < 0 && ! TREE_UNSIGNED (TREE_TYPE (i)))
1439 d = (double) (~ TREE_INT_CST_HIGH (i));
1440 e = ((double) ((HOST_WIDE_INT) 1 << (HOST_BITS_PER_WIDE_INT / 2))
1441 * (double) ((HOST_WIDE_INT) 1 << (HOST_BITS_PER_WIDE_INT / 2)));
1443 e = (double) (unsigned HOST_WIDE_INT) (~ TREE_INT_CST_LOW (i));
1451 d = (double) (unsigned HOST_WIDE_INT) TREE_INT_CST_HIGH (i);
1452 e = ((double) ((HOST_WIDE_INT) 1 << (HOST_BITS_PER_WIDE_INT / 2))
1453 * (double) ((HOST_WIDE_INT) 1 << (HOST_BITS_PER_WIDE_INT / 2)));
1455 e = (double) (unsigned HOST_WIDE_INT) TREE_INT_CST_LOW (i);
1458 #endif /* not REAL_ARITHMETIC */
1462 /* This function can't be implemented if we can't do arithmetic
1463 on the float representation. */
1466 build_real_from_int_cst (type, i)
1471 int overflow = TREE_OVERFLOW (i);
1473 jmp_buf float_error;
1475 v = make_node (REAL_CST);
1476 TREE_TYPE (v) = type;
1478 if (setjmp (float_error))
1485 set_float_handler (float_error);
1487 #ifdef REAL_ARITHMETIC
1488 d = real_value_from_int_cst (type, i);
1490 d = REAL_VALUE_TRUNCATE (TYPE_MODE (type),
1491 real_value_from_int_cst (type, i));
1494 /* Check for valid float value for this type on this target machine. */
1497 set_float_handler (NULL_PTR);
1499 #ifdef CHECK_FLOAT_VALUE
1500 CHECK_FLOAT_VALUE (TYPE_MODE (type), d, overflow);
1503 TREE_REAL_CST (v) = d;
1504 TREE_OVERFLOW (v) = TREE_CONSTANT_OVERFLOW (v) = overflow;
1508 #endif /* not REAL_IS_NOT_DOUBLE, or REAL_ARITHMETIC */
1510 /* Return a newly constructed STRING_CST node whose value is
1511 the LEN characters at STR.
1512 The TREE_TYPE is not initialized. */
1515 build_string (len, str)
1519 /* Put the string in saveable_obstack since it will be placed in the RTL
1520 for an "asm" statement and will also be kept around a while if
1521 deferring constant output in varasm.c. */
1523 register tree s = make_node (STRING_CST);
1524 TREE_STRING_LENGTH (s) = len;
1525 TREE_STRING_POINTER (s) = obstack_copy0 (saveable_obstack, str, len);
1529 /* Return a newly constructed COMPLEX_CST node whose value is
1530 specified by the real and imaginary parts REAL and IMAG.
1531 Both REAL and IMAG should be constant nodes. TYPE, if specified,
1532 will be the type of the COMPLEX_CST; otherwise a new type will be made. */
1535 build_complex (type, real, imag)
1539 register tree t = make_node (COMPLEX_CST);
1541 TREE_REALPART (t) = real;
1542 TREE_IMAGPART (t) = imag;
1543 TREE_TYPE (t) = type ? type : build_complex_type (TREE_TYPE (real));
1544 TREE_OVERFLOW (t) = TREE_OVERFLOW (real) | TREE_OVERFLOW (imag);
1545 TREE_CONSTANT_OVERFLOW (t)
1546 = TREE_CONSTANT_OVERFLOW (real) | TREE_CONSTANT_OVERFLOW (imag);
1550 /* Build a newly constructed TREE_VEC node of length LEN. */
1557 register int length = (len-1) * sizeof (tree) + sizeof (struct tree_vec);
1558 register struct obstack *obstack = current_obstack;
1561 #ifdef GATHER_STATISTICS
1562 tree_node_counts[(int)vec_kind]++;
1563 tree_node_sizes[(int)vec_kind] += length;
1566 t = (tree) obstack_alloc (obstack, length);
1568 for (i = (length / sizeof (int)) - 1; i >= 0; i--)
1571 TREE_SET_CODE (t, TREE_VEC);
1572 TREE_VEC_LENGTH (t) = len;
1573 if (obstack == &permanent_obstack)
1574 TREE_PERMANENT (t) = 1;
1579 /* Return 1 if EXPR is the integer constant zero or a complex constant
1583 integer_zerop (expr)
1588 return ((TREE_CODE (expr) == INTEGER_CST
1589 && ! TREE_CONSTANT_OVERFLOW (expr)
1590 && TREE_INT_CST_LOW (expr) == 0
1591 && TREE_INT_CST_HIGH (expr) == 0)
1592 || (TREE_CODE (expr) == COMPLEX_CST
1593 && integer_zerop (TREE_REALPART (expr))
1594 && integer_zerop (TREE_IMAGPART (expr))));
1597 /* Return 1 if EXPR is the integer constant one or the corresponding
1598 complex constant. */
1606 return ((TREE_CODE (expr) == INTEGER_CST
1607 && ! TREE_CONSTANT_OVERFLOW (expr)
1608 && TREE_INT_CST_LOW (expr) == 1
1609 && TREE_INT_CST_HIGH (expr) == 0)
1610 || (TREE_CODE (expr) == COMPLEX_CST
1611 && integer_onep (TREE_REALPART (expr))
1612 && integer_zerop (TREE_IMAGPART (expr))));
1615 /* Return 1 if EXPR is an integer containing all 1's in as much precision as
1616 it contains. Likewise for the corresponding complex constant. */
1619 integer_all_onesp (expr)
1627 if (TREE_CODE (expr) == COMPLEX_CST
1628 && integer_all_onesp (TREE_REALPART (expr))
1629 && integer_zerop (TREE_IMAGPART (expr)))
1632 else if (TREE_CODE (expr) != INTEGER_CST
1633 || TREE_CONSTANT_OVERFLOW (expr))
1636 uns = TREE_UNSIGNED (TREE_TYPE (expr));
1638 return TREE_INT_CST_LOW (expr) == -1 && TREE_INT_CST_HIGH (expr) == -1;
1640 /* Note that using TYPE_PRECISION here is wrong. We care about the
1641 actual bits, not the (arbitrary) range of the type. */
1642 prec = GET_MODE_BITSIZE (TYPE_MODE (TREE_TYPE (expr)));
1643 if (prec >= HOST_BITS_PER_WIDE_INT)
1645 int high_value, shift_amount;
1647 shift_amount = prec - HOST_BITS_PER_WIDE_INT;
1649 if (shift_amount > HOST_BITS_PER_WIDE_INT)
1650 /* Can not handle precisions greater than twice the host int size. */
1652 else if (shift_amount == HOST_BITS_PER_WIDE_INT)
1653 /* Shifting by the host word size is undefined according to the ANSI
1654 standard, so we must handle this as a special case. */
1657 high_value = ((HOST_WIDE_INT) 1 << shift_amount) - 1;
1659 return TREE_INT_CST_LOW (expr) == -1
1660 && TREE_INT_CST_HIGH (expr) == high_value;
1663 return TREE_INT_CST_LOW (expr) == ((HOST_WIDE_INT) 1 << prec) - 1;
1666 /* Return 1 if EXPR is an integer constant that is a power of 2 (i.e., has only
1670 integer_pow2p (expr)
1674 HOST_WIDE_INT high, low;
1678 if (TREE_CODE (expr) == COMPLEX_CST
1679 && integer_pow2p (TREE_REALPART (expr))
1680 && integer_zerop (TREE_IMAGPART (expr)))
1683 if (TREE_CODE (expr) != INTEGER_CST || TREE_CONSTANT_OVERFLOW (expr))
1686 prec = (TREE_CODE (TREE_TYPE (expr)) == POINTER_TYPE
1687 ? POINTER_SIZE : TYPE_PRECISION (TREE_TYPE (expr)));
1688 high = TREE_INT_CST_HIGH (expr);
1689 low = TREE_INT_CST_LOW (expr);
1691 /* First clear all bits that are beyond the type's precision in case
1692 we've been sign extended. */
1694 if (prec == 2 * HOST_BITS_PER_WIDE_INT)
1696 else if (prec > HOST_BITS_PER_WIDE_INT)
1697 high &= ~((HOST_WIDE_INT) (-1) << (prec - HOST_BITS_PER_WIDE_INT));
1701 if (prec < HOST_BITS_PER_WIDE_INT)
1702 low &= ~((HOST_WIDE_INT) (-1) << prec);
1705 if (high == 0 && low == 0)
1708 return ((high == 0 && (low & (low - 1)) == 0)
1709 || (low == 0 && (high & (high - 1)) == 0));
1712 /* Return the power of two represented by a tree node known to be a
1720 HOST_WIDE_INT high, low;
1724 if (TREE_CODE (expr) == COMPLEX_CST)
1725 return tree_log2 (TREE_REALPART (expr));
1727 prec = (TREE_CODE (TREE_TYPE (expr)) == POINTER_TYPE
1728 ? POINTER_SIZE : TYPE_PRECISION (TREE_TYPE (expr)));
1730 high = TREE_INT_CST_HIGH (expr);
1731 low = TREE_INT_CST_LOW (expr);
1733 /* First clear all bits that are beyond the type's precision in case
1734 we've been sign extended. */
1736 if (prec == 2 * HOST_BITS_PER_WIDE_INT)
1738 else if (prec > HOST_BITS_PER_WIDE_INT)
1739 high &= ~((HOST_WIDE_INT) (-1) << (prec - HOST_BITS_PER_WIDE_INT));
1743 if (prec < HOST_BITS_PER_WIDE_INT)
1744 low &= ~((HOST_WIDE_INT) (-1) << prec);
1747 return (high != 0 ? HOST_BITS_PER_WIDE_INT + exact_log2 (high)
1748 : exact_log2 (low));
1751 /* Return 1 if EXPR is the real constant zero. */
1759 return ((TREE_CODE (expr) == REAL_CST
1760 && ! TREE_CONSTANT_OVERFLOW (expr)
1761 && REAL_VALUES_EQUAL (TREE_REAL_CST (expr), dconst0))
1762 || (TREE_CODE (expr) == COMPLEX_CST
1763 && real_zerop (TREE_REALPART (expr))
1764 && real_zerop (TREE_IMAGPART (expr))));
1767 /* Return 1 if EXPR is the real constant one in real or complex form. */
1775 return ((TREE_CODE (expr) == REAL_CST
1776 && ! TREE_CONSTANT_OVERFLOW (expr)
1777 && REAL_VALUES_EQUAL (TREE_REAL_CST (expr), dconst1))
1778 || (TREE_CODE (expr) == COMPLEX_CST
1779 && real_onep (TREE_REALPART (expr))
1780 && real_zerop (TREE_IMAGPART (expr))));
1783 /* Return 1 if EXPR is the real constant two. */
1791 return ((TREE_CODE (expr) == REAL_CST
1792 && ! TREE_CONSTANT_OVERFLOW (expr)
1793 && REAL_VALUES_EQUAL (TREE_REAL_CST (expr), dconst2))
1794 || (TREE_CODE (expr) == COMPLEX_CST
1795 && real_twop (TREE_REALPART (expr))
1796 && real_zerop (TREE_IMAGPART (expr))));
1799 /* Nonzero if EXP is a constant or a cast of a constant. */
1802 really_constant_p (exp)
1805 /* This is not quite the same as STRIP_NOPS. It does more. */
1806 while (TREE_CODE (exp) == NOP_EXPR
1807 || TREE_CODE (exp) == CONVERT_EXPR
1808 || TREE_CODE (exp) == NON_LVALUE_EXPR)
1809 exp = TREE_OPERAND (exp, 0);
1810 return TREE_CONSTANT (exp);
1813 /* Return first list element whose TREE_VALUE is ELEM.
1814 Return 0 if ELEM is not in LIST. */
1817 value_member (elem, list)
1822 if (elem == TREE_VALUE (list))
1824 list = TREE_CHAIN (list);
1829 /* Return first list element whose TREE_PURPOSE is ELEM.
1830 Return 0 if ELEM is not in LIST. */
1833 purpose_member (elem, list)
1838 if (elem == TREE_PURPOSE (list))
1840 list = TREE_CHAIN (list);
1845 /* Return first list element whose BINFO_TYPE is ELEM.
1846 Return 0 if ELEM is not in LIST. */
1849 binfo_member (elem, list)
1854 if (elem == BINFO_TYPE (list))
1856 list = TREE_CHAIN (list);
1861 /* Return nonzero if ELEM is part of the chain CHAIN. */
1864 chain_member (elem, chain)
1871 chain = TREE_CHAIN (chain);
1877 /* Return nonzero if ELEM is equal to TREE_VALUE (CHAIN) for any piece of
1879 /* ??? This function was added for machine specific attributes but is no
1880 longer used. It could be deleted if we could confirm all front ends
1884 chain_member_value (elem, chain)
1889 if (elem == TREE_VALUE (chain))
1891 chain = TREE_CHAIN (chain);
1897 /* Return nonzero if ELEM is equal to TREE_PURPOSE (CHAIN)
1898 for any piece of chain CHAIN. */
1899 /* ??? This function was added for machine specific attributes but is no
1900 longer used. It could be deleted if we could confirm all front ends
1904 chain_member_purpose (elem, chain)
1909 if (elem == TREE_PURPOSE (chain))
1911 chain = TREE_CHAIN (chain);
1917 /* Return the length of a chain of nodes chained through TREE_CHAIN.
1918 We expect a null pointer to mark the end of the chain.
1919 This is the Lisp primitive `length'. */
1926 register int len = 0;
1928 for (tail = t; tail; tail = TREE_CHAIN (tail))
1934 /* Concatenate two chains of nodes (chained through TREE_CHAIN)
1935 by modifying the last node in chain 1 to point to chain 2.
1936 This is the Lisp primitive `nconc'. */
1948 for (t1 = op1; TREE_CHAIN (t1); t1 = TREE_CHAIN (t1))
1950 TREE_CHAIN (t1) = op2;
1951 for (t2 = op2; t2; t2 = TREE_CHAIN (t2))
1953 abort (); /* Circularity created. */
1959 /* Return the last node in a chain of nodes (chained through TREE_CHAIN). */
1963 register tree chain;
1967 while ((next = TREE_CHAIN (chain)))
1972 /* Reverse the order of elements in the chain T,
1973 and return the new head of the chain (old last element). */
1979 register tree prev = 0, decl, next;
1980 for (decl = t; decl; decl = next)
1982 next = TREE_CHAIN (decl);
1983 TREE_CHAIN (decl) = prev;
1989 /* Given a chain CHAIN of tree nodes,
1990 construct and return a list of those nodes. */
1996 tree result = NULL_TREE;
1997 tree in_tail = chain;
1998 tree out_tail = NULL_TREE;
2002 tree next = tree_cons (NULL_TREE, in_tail, NULL_TREE);
2004 TREE_CHAIN (out_tail) = next;
2008 in_tail = TREE_CHAIN (in_tail);
2014 /* Return a newly created TREE_LIST node whose
2015 purpose and value fields are PARM and VALUE. */
2018 build_tree_list (parm, value)
2021 register tree t = make_node (TREE_LIST);
2022 TREE_PURPOSE (t) = parm;
2023 TREE_VALUE (t) = value;
2027 /* Similar, but build on the temp_decl_obstack. */
2030 build_decl_list (parm, value)
2034 register struct obstack *ambient_obstack = current_obstack;
2035 current_obstack = &temp_decl_obstack;
2036 node = build_tree_list (parm, value);
2037 current_obstack = ambient_obstack;
2041 /* Similar, but build on the expression_obstack. */
2044 build_expr_list (parm, value)
2048 register struct obstack *ambient_obstack = current_obstack;
2049 current_obstack = expression_obstack;
2050 node = build_tree_list (parm, value);
2051 current_obstack = ambient_obstack;
2055 /* Return a newly created TREE_LIST node whose
2056 purpose and value fields are PARM and VALUE
2057 and whose TREE_CHAIN is CHAIN. */
2060 tree_cons (purpose, value, chain)
2061 tree purpose, value, chain;
2064 register tree node = make_node (TREE_LIST);
2067 register tree node = (tree) obstack_alloc (current_obstack, sizeof (struct tree_list));
2068 #ifdef GATHER_STATISTICS
2069 tree_node_counts[(int)x_kind]++;
2070 tree_node_sizes[(int)x_kind] += sizeof (struct tree_list);
2073 for (i = (sizeof (struct tree_common) / sizeof (int)) - 1; i >= 0; i--)
2074 ((int *) node)[i] = 0;
2076 TREE_SET_CODE (node, TREE_LIST);
2077 if (current_obstack == &permanent_obstack)
2078 TREE_PERMANENT (node) = 1;
2081 TREE_CHAIN (node) = chain;
2082 TREE_PURPOSE (node) = purpose;
2083 TREE_VALUE (node) = value;
2087 /* Similar, but build on the temp_decl_obstack. */
2090 decl_tree_cons (purpose, value, chain)
2091 tree purpose, value, chain;
2094 register struct obstack *ambient_obstack = current_obstack;
2095 current_obstack = &temp_decl_obstack;
2096 node = tree_cons (purpose, value, chain);
2097 current_obstack = ambient_obstack;
2101 /* Similar, but build on the expression_obstack. */
2104 expr_tree_cons (purpose, value, chain)
2105 tree purpose, value, chain;
2108 register struct obstack *ambient_obstack = current_obstack;
2109 current_obstack = expression_obstack;
2110 node = tree_cons (purpose, value, chain);
2111 current_obstack = ambient_obstack;
2115 /* Same as `tree_cons' but make a permanent object. */
2118 perm_tree_cons (purpose, value, chain)
2119 tree purpose, value, chain;
2122 register struct obstack *ambient_obstack = current_obstack;
2123 current_obstack = &permanent_obstack;
2125 node = tree_cons (purpose, value, chain);
2126 current_obstack = ambient_obstack;
2130 /* Same as `tree_cons', but make this node temporary, regardless. */
2133 temp_tree_cons (purpose, value, chain)
2134 tree purpose, value, chain;
2137 register struct obstack *ambient_obstack = current_obstack;
2138 current_obstack = &temporary_obstack;
2140 node = tree_cons (purpose, value, chain);
2141 current_obstack = ambient_obstack;
2145 /* Same as `tree_cons', but save this node if the function's RTL is saved. */
2148 saveable_tree_cons (purpose, value, chain)
2149 tree purpose, value, chain;
2152 register struct obstack *ambient_obstack = current_obstack;
2153 current_obstack = saveable_obstack;
2155 node = tree_cons (purpose, value, chain);
2156 current_obstack = ambient_obstack;
2160 /* Return the size nominally occupied by an object of type TYPE
2161 when it resides in memory. The value is measured in units of bytes,
2162 and its data type is that normally used for type sizes
2163 (which is the first type created by make_signed_type or
2164 make_unsigned_type). */
2167 size_in_bytes (type)
2172 if (type == error_mark_node)
2173 return integer_zero_node;
2174 type = TYPE_MAIN_VARIANT (type);
2175 if (TYPE_SIZE (type) == 0)
2177 incomplete_type_error (NULL_TREE, type);
2178 return integer_zero_node;
2180 t = size_binop (CEIL_DIV_EXPR, TYPE_SIZE (type),
2181 size_int (BITS_PER_UNIT));
2182 if (TREE_CODE (t) == INTEGER_CST)
2183 force_fit_type (t, 0);
2187 /* Return the size of TYPE (in bytes) as an integer,
2188 or return -1 if the size can vary. */
2191 int_size_in_bytes (type)
2195 if (type == error_mark_node)
2197 type = TYPE_MAIN_VARIANT (type);
2198 if (TYPE_SIZE (type) == 0)
2200 if (TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
2202 if (TREE_INT_CST_HIGH (TYPE_SIZE (type)) != 0)
2204 tree t = size_binop (CEIL_DIV_EXPR, TYPE_SIZE (type),
2205 size_int (BITS_PER_UNIT));
2206 return TREE_INT_CST_LOW (t);
2208 size = TREE_INT_CST_LOW (TYPE_SIZE (type));
2209 return (size + BITS_PER_UNIT - 1) / BITS_PER_UNIT;
2212 /* Return, as a tree node, the number of elements for TYPE (which is an
2213 ARRAY_TYPE) minus one. This counts only elements of the top array.
2215 Don't let any SAVE_EXPRs escape; if we are called as part of a cleanup
2216 action, they would get unsaved. */
2219 array_type_nelts (type)
2222 tree index_type, min, max;
2224 /* If they did it with unspecified bounds, then we should have already
2225 given an error about it before we got here. */
2226 if (! TYPE_DOMAIN (type))
2227 return error_mark_node;
2229 index_type = TYPE_DOMAIN (type);
2230 min = TYPE_MIN_VALUE (index_type);
2231 max = TYPE_MAX_VALUE (index_type);
2233 if (! TREE_CONSTANT (min))
2236 if (TREE_CODE (min) == SAVE_EXPR)
2237 min = build (RTL_EXPR, TREE_TYPE (TYPE_MIN_VALUE (index_type)), 0,
2238 SAVE_EXPR_RTL (min));
2240 min = TYPE_MIN_VALUE (index_type);
2243 if (! TREE_CONSTANT (max))
2246 if (TREE_CODE (max) == SAVE_EXPR)
2247 max = build (RTL_EXPR, TREE_TYPE (TYPE_MAX_VALUE (index_type)), 0,
2248 SAVE_EXPR_RTL (max));
2250 max = TYPE_MAX_VALUE (index_type);
2253 return (integer_zerop (min)
2255 : fold (build (MINUS_EXPR, TREE_TYPE (max), max, min)));
2258 /* Return nonzero if arg is static -- a reference to an object in
2259 static storage. This is not the same as the C meaning of `static'. */
2265 switch (TREE_CODE (arg))
2268 /* Nested functions aren't static, since taking their address
2269 involves a trampoline. */
2270 return decl_function_context (arg) == 0 || DECL_NO_STATIC_CHAIN (arg);
2272 return TREE_STATIC (arg) || DECL_EXTERNAL (arg);
2275 return TREE_STATIC (arg);
2280 /* If we are referencing a bitfield, we can't evaluate an
2281 ADDR_EXPR at compile time and so it isn't a constant. */
2283 return (! DECL_BIT_FIELD (TREE_OPERAND (arg, 1))
2284 && staticp (TREE_OPERAND (arg, 0)));
2290 /* This case is technically correct, but results in setting
2291 TREE_CONSTANT on ADDR_EXPRs that cannot be evaluated at
2294 return TREE_CONSTANT (TREE_OPERAND (arg, 0));
2298 if (TREE_CODE (TYPE_SIZE (TREE_TYPE (arg))) == INTEGER_CST
2299 && TREE_CODE (TREE_OPERAND (arg, 1)) == INTEGER_CST)
2300 return staticp (TREE_OPERAND (arg, 0));
2307 /* Wrap a SAVE_EXPR around EXPR, if appropriate.
2308 Do this to any expression which may be used in more than one place,
2309 but must be evaluated only once.
2311 Normally, expand_expr would reevaluate the expression each time.
2312 Calling save_expr produces something that is evaluated and recorded
2313 the first time expand_expr is called on it. Subsequent calls to
2314 expand_expr just reuse the recorded value.
2316 The call to expand_expr that generates code that actually computes
2317 the value is the first call *at compile time*. Subsequent calls
2318 *at compile time* generate code to use the saved value.
2319 This produces correct result provided that *at run time* control
2320 always flows through the insns made by the first expand_expr
2321 before reaching the other places where the save_expr was evaluated.
2322 You, the caller of save_expr, must make sure this is so.
2324 Constants, and certain read-only nodes, are returned with no
2325 SAVE_EXPR because that is safe. Expressions containing placeholders
2326 are not touched; see tree.def for an explanation of what these
2333 register tree t = fold (expr);
2335 /* We don't care about whether this can be used as an lvalue in this
2337 while (TREE_CODE (t) == NON_LVALUE_EXPR)
2338 t = TREE_OPERAND (t, 0);
2340 /* If the tree evaluates to a constant, then we don't want to hide that
2341 fact (i.e. this allows further folding, and direct checks for constants).
2342 However, a read-only object that has side effects cannot be bypassed.
2343 Since it is no problem to reevaluate literals, we just return the
2346 if (TREE_CONSTANT (t) || (TREE_READONLY (t) && ! TREE_SIDE_EFFECTS (t))
2347 || TREE_CODE (t) == SAVE_EXPR || TREE_CODE (t) == ERROR_MARK)
2350 /* If T contains a PLACEHOLDER_EXPR, we must evaluate it each time, since
2351 it means that the size or offset of some field of an object depends on
2352 the value within another field.
2354 Note that it must not be the case that T contains both a PLACEHOLDER_EXPR
2355 and some variable since it would then need to be both evaluated once and
2356 evaluated more than once. Front-ends must assure this case cannot
2357 happen by surrounding any such subexpressions in their own SAVE_EXPR
2358 and forcing evaluation at the proper time. */
2359 if (contains_placeholder_p (t))
2362 t = build (SAVE_EXPR, TREE_TYPE (expr), t, current_function_decl, NULL_TREE);
2364 /* This expression might be placed ahead of a jump to ensure that the
2365 value was computed on both sides of the jump. So make sure it isn't
2366 eliminated as dead. */
2367 TREE_SIDE_EFFECTS (t) = 1;
2371 /* Arrange for an expression to be expanded multiple independent
2372 times. This is useful for cleanup actions, as the backend can
2373 expand them multiple times in different places. */
2381 /* If this is already protected, no sense in protecting it again. */
2382 if (TREE_CODE (expr) == UNSAVE_EXPR)
2385 t = build1 (UNSAVE_EXPR, TREE_TYPE (expr), expr);
2386 TREE_SIDE_EFFECTS (t) = TREE_SIDE_EFFECTS (expr);
2390 /* Returns the index of the first non-tree operand for CODE, or the number
2391 of operands if all are trees. */
2395 enum tree_code code;
2405 case WITH_CLEANUP_EXPR:
2406 /* Should be defined to be 2. */
2408 case METHOD_CALL_EXPR:
2411 return tree_code_length [(int) code];
2415 /* Modify a tree in place so that all the evaluate only once things
2416 are cleared out. Return the EXPR given. */
2419 unsave_expr_now (expr)
2422 enum tree_code code;
2426 if (expr == NULL_TREE)
2429 code = TREE_CODE (expr);
2430 first_rtl = first_rtl_op (code);
2434 SAVE_EXPR_RTL (expr) = 0;
2438 TREE_OPERAND (expr, 1) = TREE_OPERAND (expr, 3);
2439 TREE_OPERAND (expr, 3) = NULL_TREE;
2443 /* I don't yet know how to emit a sequence multiple times. */
2444 if (RTL_EXPR_SEQUENCE (expr) != 0)
2449 CALL_EXPR_RTL (expr) = 0;
2450 if (TREE_OPERAND (expr, 1)
2451 && TREE_CODE (TREE_OPERAND (expr, 1)) == TREE_LIST)
2453 tree exp = TREE_OPERAND (expr, 1);
2456 unsave_expr_now (TREE_VALUE (exp));
2457 exp = TREE_CHAIN (exp);
2466 switch (TREE_CODE_CLASS (code))
2468 case 'c': /* a constant */
2469 case 't': /* a type node */
2470 case 'x': /* something random, like an identifier or an ERROR_MARK. */
2471 case 'd': /* A decl node */
2472 case 'b': /* A block node */
2475 case 'e': /* an expression */
2476 case 'r': /* a reference */
2477 case 's': /* an expression with side effects */
2478 case '<': /* a comparison expression */
2479 case '2': /* a binary arithmetic expression */
2480 case '1': /* a unary arithmetic expression */
2481 for (i = first_rtl - 1; i >= 0; i--)
2482 unsave_expr_now (TREE_OPERAND (expr, i));
2490 /* Return 1 if EXP contains a PLACEHOLDER_EXPR; i.e., if it represents a size
2491 or offset that depends on a field within a record. */
2494 contains_placeholder_p (exp)
2497 register enum tree_code code = TREE_CODE (exp);
2500 /* If we have a WITH_RECORD_EXPR, it "cancels" any PLACEHOLDER_EXPR
2501 in it since it is supplying a value for it. */
2502 if (code == WITH_RECORD_EXPR)
2504 else if (code == PLACEHOLDER_EXPR)
2507 switch (TREE_CODE_CLASS (code))
2510 /* Don't look at any PLACEHOLDER_EXPRs that might be in index or bit
2511 position computations since they will be converted into a
2512 WITH_RECORD_EXPR involving the reference, which will assume
2513 here will be valid. */
2514 return contains_placeholder_p (TREE_OPERAND (exp, 0));
2517 if (code == TREE_LIST)
2518 return (contains_placeholder_p (TREE_VALUE (exp))
2519 || (TREE_CHAIN (exp) != 0
2520 && contains_placeholder_p (TREE_CHAIN (exp))));
2529 /* Ignoring the first operand isn't quite right, but works best. */
2530 return contains_placeholder_p (TREE_OPERAND (exp, 1));
2537 return (contains_placeholder_p (TREE_OPERAND (exp, 0))
2538 || contains_placeholder_p (TREE_OPERAND (exp, 1))
2539 || contains_placeholder_p (TREE_OPERAND (exp, 2)));
2542 /* If we already know this doesn't have a placeholder, don't
2544 if (SAVE_EXPR_NOPLACEHOLDER (exp) || SAVE_EXPR_RTL (exp) != 0)
2547 SAVE_EXPR_NOPLACEHOLDER (exp) = 1;
2548 result = contains_placeholder_p (TREE_OPERAND (exp, 0));
2550 SAVE_EXPR_NOPLACEHOLDER (exp) = 0;
2555 return (TREE_OPERAND (exp, 1) != 0
2556 && contains_placeholder_p (TREE_OPERAND (exp, 1)));
2562 switch (tree_code_length[(int) code])
2565 return contains_placeholder_p (TREE_OPERAND (exp, 0));
2567 return (contains_placeholder_p (TREE_OPERAND (exp, 0))
2568 || contains_placeholder_p (TREE_OPERAND (exp, 1)));
2579 /* Return 1 if EXP contains any expressions that produce cleanups for an
2580 outer scope to deal with. Used by fold. */
2588 if (! TREE_SIDE_EFFECTS (exp))
2591 switch (TREE_CODE (exp))
2594 case WITH_CLEANUP_EXPR:
2597 case CLEANUP_POINT_EXPR:
2601 for (exp = TREE_OPERAND (exp, 1); exp; exp = TREE_CHAIN (exp))
2603 cmp = has_cleanups (TREE_VALUE (exp));
2613 /* This general rule works for most tree codes. All exceptions should be
2614 handled above. If this is a language-specific tree code, we can't
2615 trust what might be in the operand, so say we don't know
2617 if ((int) TREE_CODE (exp) >= (int) LAST_AND_UNUSED_TREE_CODE)
2620 nops = first_rtl_op (TREE_CODE (exp));
2621 for (i = 0; i < nops; i++)
2622 if (TREE_OPERAND (exp, i) != 0)
2624 int type = TREE_CODE_CLASS (TREE_CODE (TREE_OPERAND (exp, i)));
2625 if (type == 'e' || type == '<' || type == '1' || type == '2'
2626 || type == 'r' || type == 's')
2628 cmp = has_cleanups (TREE_OPERAND (exp, i));
2637 /* Given a tree EXP, a FIELD_DECL F, and a replacement value R,
2638 return a tree with all occurrences of references to F in a
2639 PLACEHOLDER_EXPR replaced by R. Note that we assume here that EXP
2640 contains only arithmetic expressions or a CALL_EXPR with a
2641 PLACEHOLDER_EXPR occurring only in its arglist. */
2644 substitute_in_expr (exp, f, r)
2649 enum tree_code code = TREE_CODE (exp);
2654 switch (TREE_CODE_CLASS (code))
2661 if (code == PLACEHOLDER_EXPR)
2663 else if (code == TREE_LIST)
2665 op0 = (TREE_CHAIN (exp) == 0
2666 ? 0 : substitute_in_expr (TREE_CHAIN (exp), f, r));
2667 op1 = substitute_in_expr (TREE_VALUE (exp), f, r);
2668 if (op0 == TREE_CHAIN (exp) && op1 == TREE_VALUE (exp))
2671 return tree_cons (TREE_PURPOSE (exp), op1, op0);
2680 switch (tree_code_length[(int) code])
2683 op0 = substitute_in_expr (TREE_OPERAND (exp, 0), f, r);
2684 if (op0 == TREE_OPERAND (exp, 0))
2687 new = fold (build1 (code, TREE_TYPE (exp), op0));
2691 /* An RTL_EXPR cannot contain a PLACEHOLDER_EXPR; a CONSTRUCTOR
2692 could, but we don't support it. */
2693 if (code == RTL_EXPR)
2695 else if (code == CONSTRUCTOR)
2698 op0 = substitute_in_expr (TREE_OPERAND (exp, 0), f, r);
2699 op1 = substitute_in_expr (TREE_OPERAND (exp, 1), f, r);
2700 if (op0 == TREE_OPERAND (exp, 0) && op1 == TREE_OPERAND (exp, 1))
2703 new = fold (build (code, TREE_TYPE (exp), op0, op1));
2707 /* It cannot be that anything inside a SAVE_EXPR contains a
2708 PLACEHOLDER_EXPR. */
2709 if (code == SAVE_EXPR)
2712 else if (code == CALL_EXPR)
2714 op1 = substitute_in_expr (TREE_OPERAND (exp, 1), f, r);
2715 if (op1 == TREE_OPERAND (exp, 1))
2718 return build (code, TREE_TYPE (exp),
2719 TREE_OPERAND (exp, 0), op1, NULL_TREE);
2722 else if (code != COND_EXPR)
2725 op0 = substitute_in_expr (TREE_OPERAND (exp, 0), f, r);
2726 op1 = substitute_in_expr (TREE_OPERAND (exp, 1), f, r);
2727 op2 = substitute_in_expr (TREE_OPERAND (exp, 2), f, r);
2728 if (op0 == TREE_OPERAND (exp, 0) && op1 == TREE_OPERAND (exp, 1)
2729 && op2 == TREE_OPERAND (exp, 2))
2732 new = fold (build (code, TREE_TYPE (exp), op0, op1, op2));
2745 /* If this expression is getting a value from a PLACEHOLDER_EXPR
2746 and it is the right field, replace it with R. */
2747 for (inner = TREE_OPERAND (exp, 0);
2748 TREE_CODE_CLASS (TREE_CODE (inner)) == 'r';
2749 inner = TREE_OPERAND (inner, 0))
2751 if (TREE_CODE (inner) == PLACEHOLDER_EXPR
2752 && TREE_OPERAND (exp, 1) == f)
2755 /* If this expression hasn't been completed let, leave it
2757 if (TREE_CODE (inner) == PLACEHOLDER_EXPR
2758 && TREE_TYPE (inner) == 0)
2761 op0 = substitute_in_expr (TREE_OPERAND (exp, 0), f, r);
2762 if (op0 == TREE_OPERAND (exp, 0))
2765 new = fold (build (code, TREE_TYPE (exp), op0,
2766 TREE_OPERAND (exp, 1)));
2770 op0 = substitute_in_expr (TREE_OPERAND (exp, 0), f, r);
2771 op1 = substitute_in_expr (TREE_OPERAND (exp, 1), f, r);
2772 op2 = substitute_in_expr (TREE_OPERAND (exp, 2), f, r);
2773 if (op0 == TREE_OPERAND (exp, 0) && op1 == TREE_OPERAND (exp, 1)
2774 && op2 == TREE_OPERAND (exp, 2))
2777 new = fold (build (code, TREE_TYPE (exp), op0, op1, op2));
2782 op0 = substitute_in_expr (TREE_OPERAND (exp, 0), f, r);
2783 if (op0 == TREE_OPERAND (exp, 0))
2786 new = fold (build1 (code, TREE_TYPE (exp), op0));
2798 TREE_READONLY (new) = TREE_READONLY (exp);
2802 /* Stabilize a reference so that we can use it any number of times
2803 without causing its operands to be evaluated more than once.
2804 Returns the stabilized reference. This works by means of save_expr,
2805 so see the caveats in the comments about save_expr.
2807 Also allows conversion expressions whose operands are references.
2808 Any other kind of expression is returned unchanged. */
2811 stabilize_reference (ref)
2814 register tree result;
2815 register enum tree_code code = TREE_CODE (ref);
2822 /* No action is needed in this case. */
2828 case FIX_TRUNC_EXPR:
2829 case FIX_FLOOR_EXPR:
2830 case FIX_ROUND_EXPR:
2832 result = build_nt (code, stabilize_reference (TREE_OPERAND (ref, 0)));
2836 result = build_nt (INDIRECT_REF,
2837 stabilize_reference_1 (TREE_OPERAND (ref, 0)));
2841 result = build_nt (COMPONENT_REF,
2842 stabilize_reference (TREE_OPERAND (ref, 0)),
2843 TREE_OPERAND (ref, 1));
2847 result = build_nt (BIT_FIELD_REF,
2848 stabilize_reference (TREE_OPERAND (ref, 0)),
2849 stabilize_reference_1 (TREE_OPERAND (ref, 1)),
2850 stabilize_reference_1 (TREE_OPERAND (ref, 2)));
2854 result = build_nt (ARRAY_REF,
2855 stabilize_reference (TREE_OPERAND (ref, 0)),
2856 stabilize_reference_1 (TREE_OPERAND (ref, 1)));
2860 /* We cannot wrap the first expression in a SAVE_EXPR, as then
2861 it wouldn't be ignored. This matters when dealing with
2863 return stabilize_reference_1 (ref);
2866 result = build1 (INDIRECT_REF, TREE_TYPE (ref),
2867 save_expr (build1 (ADDR_EXPR,
2868 build_pointer_type (TREE_TYPE (ref)),
2873 /* If arg isn't a kind of lvalue we recognize, make no change.
2874 Caller should recognize the error for an invalid lvalue. */
2879 return error_mark_node;
2882 TREE_TYPE (result) = TREE_TYPE (ref);
2883 TREE_READONLY (result) = TREE_READONLY (ref);
2884 TREE_SIDE_EFFECTS (result) = TREE_SIDE_EFFECTS (ref);
2885 TREE_THIS_VOLATILE (result) = TREE_THIS_VOLATILE (ref);
2886 TREE_RAISES (result) = TREE_RAISES (ref);
2891 /* Subroutine of stabilize_reference; this is called for subtrees of
2892 references. Any expression with side-effects must be put in a SAVE_EXPR
2893 to ensure that it is only evaluated once.
2895 We don't put SAVE_EXPR nodes around everything, because assigning very
2896 simple expressions to temporaries causes us to miss good opportunities
2897 for optimizations. Among other things, the opportunity to fold in the
2898 addition of a constant into an addressing mode often gets lost, e.g.
2899 "y[i+1] += x;". In general, we take the approach that we should not make
2900 an assignment unless we are forced into it - i.e., that any non-side effect
2901 operator should be allowed, and that cse should take care of coalescing
2902 multiple utterances of the same expression should that prove fruitful. */
2905 stabilize_reference_1 (e)
2908 register tree result;
2909 register enum tree_code code = TREE_CODE (e);
2911 /* We cannot ignore const expressions because it might be a reference
2912 to a const array but whose index contains side-effects. But we can
2913 ignore things that are actual constant or that already have been
2914 handled by this function. */
2916 if (TREE_CONSTANT (e) || code == SAVE_EXPR)
2919 switch (TREE_CODE_CLASS (code))
2929 /* If the expression has side-effects, then encase it in a SAVE_EXPR
2930 so that it will only be evaluated once. */
2931 /* The reference (r) and comparison (<) classes could be handled as
2932 below, but it is generally faster to only evaluate them once. */
2933 if (TREE_SIDE_EFFECTS (e))
2934 return save_expr (e);
2938 /* Constants need no processing. In fact, we should never reach
2943 /* Division is slow and tends to be compiled with jumps,
2944 especially the division by powers of 2 that is often
2945 found inside of an array reference. So do it just once. */
2946 if (code == TRUNC_DIV_EXPR || code == TRUNC_MOD_EXPR
2947 || code == FLOOR_DIV_EXPR || code == FLOOR_MOD_EXPR
2948 || code == CEIL_DIV_EXPR || code == CEIL_MOD_EXPR
2949 || code == ROUND_DIV_EXPR || code == ROUND_MOD_EXPR)
2950 return save_expr (e);
2951 /* Recursively stabilize each operand. */
2952 result = build_nt (code, stabilize_reference_1 (TREE_OPERAND (e, 0)),
2953 stabilize_reference_1 (TREE_OPERAND (e, 1)));
2957 /* Recursively stabilize each operand. */
2958 result = build_nt (code, stabilize_reference_1 (TREE_OPERAND (e, 0)));
2965 TREE_TYPE (result) = TREE_TYPE (e);
2966 TREE_READONLY (result) = TREE_READONLY (e);
2967 TREE_SIDE_EFFECTS (result) = TREE_SIDE_EFFECTS (e);
2968 TREE_THIS_VOLATILE (result) = TREE_THIS_VOLATILE (e);
2969 TREE_RAISES (result) = TREE_RAISES (e);
2974 /* Low-level constructors for expressions. */
2976 /* Build an expression of code CODE, data type TYPE,
2977 and operands as specified by the arguments ARG1 and following arguments.
2978 Expressions and reference nodes can be created this way.
2979 Constants, decls, types and misc nodes cannot be. */
2982 build VPROTO((enum tree_code code, tree tt, ...))
2985 enum tree_code code;
2990 register int length;
2996 code = va_arg (p, enum tree_code);
2997 tt = va_arg (p, tree);
3000 t = make_node (code);
3001 length = tree_code_length[(int) code];
3006 /* This is equivalent to the loop below, but faster. */
3007 register tree arg0 = va_arg (p, tree);
3008 register tree arg1 = va_arg (p, tree);
3009 TREE_OPERAND (t, 0) = arg0;
3010 TREE_OPERAND (t, 1) = arg1;
3011 if ((arg0 && TREE_SIDE_EFFECTS (arg0))
3012 || (arg1 && TREE_SIDE_EFFECTS (arg1)))
3013 TREE_SIDE_EFFECTS (t) = 1;
3015 = (arg0 && TREE_RAISES (arg0)) || (arg1 && TREE_RAISES (arg1));
3017 else if (length == 1)
3019 register tree arg0 = va_arg (p, tree);
3021 /* Call build1 for this! */
3022 if (TREE_CODE_CLASS (code) != 's')
3024 TREE_OPERAND (t, 0) = arg0;
3025 if (arg0 && TREE_SIDE_EFFECTS (arg0))
3026 TREE_SIDE_EFFECTS (t) = 1;
3027 TREE_RAISES (t) = (arg0 && TREE_RAISES (arg0));
3031 for (i = 0; i < length; i++)
3033 register tree operand = va_arg (p, tree);
3034 TREE_OPERAND (t, i) = operand;
3037 if (TREE_SIDE_EFFECTS (operand))
3038 TREE_SIDE_EFFECTS (t) = 1;
3039 if (TREE_RAISES (operand))
3040 TREE_RAISES (t) = 1;
3048 /* Same as above, but only builds for unary operators.
3049 Saves lions share of calls to `build'; cuts down use
3050 of varargs, which is expensive for RISC machines. */
3053 build1 (code, type, node)
3054 enum tree_code code;
3058 register struct obstack *obstack = expression_obstack;
3059 register int i, length;
3060 #ifdef GATHER_STATISTICS
3061 register tree_node_kind kind;
3065 #ifdef GATHER_STATISTICS
3066 if (TREE_CODE_CLASS (code) == 'r')
3072 length = sizeof (struct tree_exp);
3074 t = (tree) obstack_alloc (obstack, length);
3076 #ifdef GATHER_STATISTICS
3077 tree_node_counts[(int)kind]++;
3078 tree_node_sizes[(int)kind] += length;
3081 for (i = (length / sizeof (int)) - 1; i >= 0; i--)
3084 TREE_TYPE (t) = type;
3085 TREE_SET_CODE (t, code);
3087 if (obstack == &permanent_obstack)
3088 TREE_PERMANENT (t) = 1;
3090 TREE_OPERAND (t, 0) = node;
3093 if (TREE_SIDE_EFFECTS (node))
3094 TREE_SIDE_EFFECTS (t) = 1;
3095 if (TREE_RAISES (node))
3096 TREE_RAISES (t) = 1;
3102 /* Similar except don't specify the TREE_TYPE
3103 and leave the TREE_SIDE_EFFECTS as 0.
3104 It is permissible for arguments to be null,
3105 or even garbage if their values do not matter. */
3108 build_nt VPROTO((enum tree_code code, ...))
3111 enum tree_code code;
3115 register int length;
3121 code = va_arg (p, enum tree_code);
3124 t = make_node (code);
3125 length = tree_code_length[(int) code];
3127 for (i = 0; i < length; i++)
3128 TREE_OPERAND (t, i) = va_arg (p, tree);
3134 /* Similar to `build_nt', except we build
3135 on the temp_decl_obstack, regardless. */
3138 build_parse_node VPROTO((enum tree_code code, ...))
3141 enum tree_code code;
3143 register struct obstack *ambient_obstack = expression_obstack;
3146 register int length;
3152 code = va_arg (p, enum tree_code);
3155 expression_obstack = &temp_decl_obstack;
3157 t = make_node (code);
3158 length = tree_code_length[(int) code];
3160 for (i = 0; i < length; i++)
3161 TREE_OPERAND (t, i) = va_arg (p, tree);
3164 expression_obstack = ambient_obstack;
3169 /* Commented out because this wants to be done very
3170 differently. See cp-lex.c. */
3172 build_op_identifier (op1, op2)
3175 register tree t = make_node (OP_IDENTIFIER);
3176 TREE_PURPOSE (t) = op1;
3177 TREE_VALUE (t) = op2;
3182 /* Create a DECL_... node of code CODE, name NAME and data type TYPE.
3183 We do NOT enter this node in any sort of symbol table.
3185 layout_decl is used to set up the decl's storage layout.
3186 Other slots are initialized to 0 or null pointers. */
3189 build_decl (code, name, type)
3190 enum tree_code code;
3195 t = make_node (code);
3197 /* if (type == error_mark_node)
3198 type = integer_type_node; */
3199 /* That is not done, deliberately, so that having error_mark_node
3200 as the type can suppress useless errors in the use of this variable. */
3202 DECL_NAME (t) = name;
3203 DECL_ASSEMBLER_NAME (t) = name;
3204 TREE_TYPE (t) = type;
3206 if (code == VAR_DECL || code == PARM_DECL || code == RESULT_DECL)
3208 else if (code == FUNCTION_DECL)
3209 DECL_MODE (t) = FUNCTION_MODE;
3214 /* BLOCK nodes are used to represent the structure of binding contours
3215 and declarations, once those contours have been exited and their contents
3216 compiled. This information is used for outputting debugging info. */
3219 build_block (vars, tags, subblocks, supercontext, chain)
3220 tree vars, tags, subblocks, supercontext, chain;
3222 register tree block = make_node (BLOCK);
3223 BLOCK_VARS (block) = vars;
3224 BLOCK_TYPE_TAGS (block) = tags;
3225 BLOCK_SUBBLOCKS (block) = subblocks;
3226 BLOCK_SUPERCONTEXT (block) = supercontext;
3227 BLOCK_CHAIN (block) = chain;
3231 /* Return a declaration like DDECL except that its DECL_MACHINE_ATTRIBUTE
3235 build_decl_attribute_variant (ddecl, attribute)
3236 tree ddecl, attribute;
3238 DECL_MACHINE_ATTRIBUTES (ddecl) = attribute;
3242 /* Return a type like TTYPE except that its TYPE_ATTRIBUTE
3245 Record such modified types already made so we don't make duplicates. */
3248 build_type_attribute_variant (ttype, attribute)
3249 tree ttype, attribute;
3251 if ( ! attribute_list_equal (TYPE_ATTRIBUTES (ttype), attribute))
3253 register int hashcode;
3254 register struct obstack *ambient_obstack = current_obstack;
3257 if (ambient_obstack != &permanent_obstack)
3258 current_obstack = TYPE_OBSTACK (ttype);
3260 ntype = copy_node (ttype);
3261 current_obstack = ambient_obstack;
3263 TYPE_POINTER_TO (ntype) = 0;
3264 TYPE_REFERENCE_TO (ntype) = 0;
3265 TYPE_ATTRIBUTES (ntype) = attribute;
3267 /* Create a new main variant of TYPE. */
3268 TYPE_MAIN_VARIANT (ntype) = ntype;
3269 TYPE_NEXT_VARIANT (ntype) = 0;
3270 TYPE_READONLY (ntype) = TYPE_VOLATILE (ntype) = 0;
3272 hashcode = TYPE_HASH (TREE_CODE (ntype))
3273 + TYPE_HASH (TREE_TYPE (ntype))
3274 + attribute_hash_list (attribute);
3276 switch (TREE_CODE (ntype))
3279 hashcode += TYPE_HASH (TYPE_ARG_TYPES (ntype));
3282 hashcode += TYPE_HASH (TYPE_DOMAIN (ntype));
3285 hashcode += TYPE_HASH (TYPE_MAX_VALUE (ntype));
3288 hashcode += TYPE_HASH (TYPE_PRECISION (ntype));
3294 ntype = type_hash_canon (hashcode, ntype);
3295 ttype = build_type_variant (ntype, TYPE_READONLY (ttype),
3296 TYPE_VOLATILE (ttype));
3302 /* Return a 1 if ATTR_NAME and ATTR_ARGS is valid for either declaration DECL
3303 or type TYPE and 0 otherwise. Validity is determined the configuration
3304 macros VALID_MACHINE_DECL_ATTRIBUTE and VALID_MACHINE_TYPE_ATTRIBUTE. */
3307 valid_machine_attribute (attr_name, attr_args, decl, type)
3308 tree attr_name, attr_args;
3313 tree decl_attr_list = decl != 0 ? DECL_MACHINE_ATTRIBUTES (decl) : 0;
3314 tree type_attr_list = TYPE_ATTRIBUTES (type);
3316 if (TREE_CODE (attr_name) != IDENTIFIER_NODE)
3319 #ifdef VALID_MACHINE_DECL_ATTRIBUTE
3321 && VALID_MACHINE_DECL_ATTRIBUTE (decl, decl_attr_list, attr_name, attr_args))
3323 tree attr = lookup_attribute (IDENTIFIER_POINTER (attr_name),
3326 if (attr != NULL_TREE)
3328 /* Override existing arguments. Declarations are unique so we can
3329 modify this in place. */
3330 TREE_VALUE (attr) = attr_args;
3334 decl_attr_list = tree_cons (attr_name, attr_args, decl_attr_list);
3335 decl = build_decl_attribute_variant (decl, decl_attr_list);
3342 #ifdef VALID_MACHINE_TYPE_ATTRIBUTE
3343 if (VALID_MACHINE_TYPE_ATTRIBUTE (type, type_attr_list, attr_name, attr_args))
3345 tree attr = lookup_attribute (IDENTIFIER_POINTER (attr_name),
3348 if (attr != NULL_TREE)
3350 /* Override existing arguments.
3351 ??? This currently works since attribute arguments are not
3352 included in `attribute_hash_list'. Something more complicated
3353 may be needed in the future. */
3354 TREE_VALUE (attr) = attr_args;
3358 type_attr_list = tree_cons (attr_name, attr_args, type_attr_list);
3359 type = build_type_attribute_variant (type, type_attr_list);
3362 TREE_TYPE (decl) = type;
3366 /* Handle putting a type attribute on pointer-to-function-type by putting
3367 the attribute on the function type. */
3368 else if (TREE_CODE (type) == POINTER_TYPE
3369 && TREE_CODE (TREE_TYPE (type)) == FUNCTION_TYPE
3370 && VALID_MACHINE_TYPE_ATTRIBUTE (TREE_TYPE (type), type_attr_list,
3371 attr_name, attr_args))
3373 tree inner_type = TREE_TYPE (type);
3374 tree inner_attr_list = TYPE_ATTRIBUTES (inner_type);
3375 tree attr = lookup_attribute (IDENTIFIER_POINTER (attr_name),
3378 if (attr != NULL_TREE)
3379 TREE_VALUE (attr) = attr_args;
3382 inner_attr_list = tree_cons (attr_name, attr_args, inner_attr_list);
3383 inner_type = build_type_attribute_variant (inner_type,
3388 TREE_TYPE (decl) = build_pointer_type (inner_type);
3397 /* Return non-zero if IDENT is a valid name for attribute ATTR,
3400 We try both `text' and `__text__', ATTR may be either one. */
3401 /* ??? It might be a reasonable simplification to require ATTR to be only
3402 `text'. One might then also require attribute lists to be stored in
3403 their canonicalized form. */
3406 is_attribute_p (attr, ident)
3410 int ident_len, attr_len;
3413 if (TREE_CODE (ident) != IDENTIFIER_NODE)
3416 if (strcmp (attr, IDENTIFIER_POINTER (ident)) == 0)
3419 p = IDENTIFIER_POINTER (ident);
3420 ident_len = strlen (p);
3421 attr_len = strlen (attr);
3423 /* If ATTR is `__text__', IDENT must be `text'; and vice versa. */
3427 || attr[attr_len - 2] != '_'
3428 || attr[attr_len - 1] != '_')
3430 if (ident_len == attr_len - 4
3431 && strncmp (attr + 2, p, attr_len - 4) == 0)
3436 if (ident_len == attr_len + 4
3437 && p[0] == '_' && p[1] == '_'
3438 && p[ident_len - 2] == '_' && p[ident_len - 1] == '_'
3439 && strncmp (attr, p + 2, attr_len) == 0)
3446 /* Given an attribute name and a list of attributes, return a pointer to the
3447 attribute's list element if the attribute is part of the list, or NULL_TREE
3451 lookup_attribute (attr_name, list)
3457 for (l = list; l; l = TREE_CHAIN (l))
3459 if (TREE_CODE (TREE_PURPOSE (l)) != IDENTIFIER_NODE)
3461 if (is_attribute_p (attr_name, TREE_PURPOSE (l)))
3468 /* Return an attribute list that is the union of a1 and a2. */
3471 merge_attributes (a1, a2)
3472 register tree a1, a2;
3476 /* Either one unset? Take the set one. */
3478 if (! (attributes = a1))
3481 /* One that completely contains the other? Take it. */
3483 else if (a2 && ! attribute_list_contained (a1, a2))
3484 if (attribute_list_contained (a2, a1))
3488 /* Pick the longest list, and hang on the other list. */
3489 /* ??? For the moment we punt on the issue of attrs with args. */
3491 if (list_length (a1) < list_length (a2))
3492 attributes = a2, a2 = a1;
3494 for (; a2; a2 = TREE_CHAIN (a2))
3495 if (lookup_attribute (IDENTIFIER_POINTER (TREE_PURPOSE (a2)),
3496 attributes) == NULL_TREE)
3498 a1 = copy_node (a2);
3499 TREE_CHAIN (a1) = attributes;
3506 /* Given types T1 and T2, merge their attributes and return
3510 merge_machine_type_attributes (t1, t2)
3513 #ifdef MERGE_MACHINE_TYPE_ATTRIBUTES
3514 return MERGE_MACHINE_TYPE_ATTRIBUTES (t1, t2);
3516 return merge_attributes (TYPE_ATTRIBUTES (t1),
3517 TYPE_ATTRIBUTES (t2));
3521 /* Given decls OLDDECL and NEWDECL, merge their attributes and return
3525 merge_machine_decl_attributes (olddecl, newdecl)
3526 tree olddecl, newdecl;
3528 #ifdef MERGE_MACHINE_DECL_ATTRIBUTES
3529 return MERGE_MACHINE_DECL_ATTRIBUTES (olddecl, newdecl);
3531 return merge_attributes (DECL_MACHINE_ATTRIBUTES (olddecl),
3532 DECL_MACHINE_ATTRIBUTES (newdecl));
3536 /* Return a type like TYPE except that its TYPE_READONLY is CONSTP
3537 and its TYPE_VOLATILE is VOLATILEP.
3539 Such variant types already made are recorded so that duplicates
3542 A variant types should never be used as the type of an expression.
3543 Always copy the variant information into the TREE_READONLY
3544 and TREE_THIS_VOLATILE of the expression, and then give the expression
3545 as its type the "main variant", the variant whose TYPE_READONLY
3546 and TYPE_VOLATILE are zero. Use TYPE_MAIN_VARIANT to find the
3550 build_type_variant (type, constp, volatilep)
3552 int constp, volatilep;
3556 /* Treat any nonzero argument as 1. */
3558 volatilep = !!volatilep;
3560 /* Search the chain of variants to see if there is already one there just
3561 like the one we need to have. If so, use that existing one. We must
3562 preserve the TYPE_NAME, since there is code that depends on this. */
3564 for (t = TYPE_MAIN_VARIANT (type); t; t = TYPE_NEXT_VARIANT (t))
3565 if (constp == TYPE_READONLY (t) && volatilep == TYPE_VOLATILE (t)
3566 && TYPE_NAME (t) == TYPE_NAME (type))
3569 /* We need a new one. */
3571 t = build_type_copy (type);
3572 TYPE_READONLY (t) = constp;
3573 TYPE_VOLATILE (t) = volatilep;
3578 /* Create a new variant of TYPE, equivalent but distinct.
3579 This is so the caller can modify it. */
3582 build_type_copy (type)
3585 register tree t, m = TYPE_MAIN_VARIANT (type);
3586 register struct obstack *ambient_obstack = current_obstack;
3588 current_obstack = TYPE_OBSTACK (type);
3589 t = copy_node (type);
3590 current_obstack = ambient_obstack;
3592 TYPE_POINTER_TO (t) = 0;
3593 TYPE_REFERENCE_TO (t) = 0;
3595 /* Add this type to the chain of variants of TYPE. */
3596 TYPE_NEXT_VARIANT (t) = TYPE_NEXT_VARIANT (m);
3597 TYPE_NEXT_VARIANT (m) = t;
3602 /* Hashing of types so that we don't make duplicates.
3603 The entry point is `type_hash_canon'. */
3605 /* Each hash table slot is a bucket containing a chain
3606 of these structures. */
3610 struct type_hash *next; /* Next structure in the bucket. */
3611 int hashcode; /* Hash code of this type. */
3612 tree type; /* The type recorded here. */
3615 /* Now here is the hash table. When recording a type, it is added
3616 to the slot whose index is the hash code mod the table size.
3617 Note that the hash table is used for several kinds of types
3618 (function types, array types and array index range types, for now).
3619 While all these live in the same table, they are completely independent,
3620 and the hash code is computed differently for each of these. */
3622 #define TYPE_HASH_SIZE 59
3623 struct type_hash *type_hash_table[TYPE_HASH_SIZE];
3625 /* Compute a hash code for a list of types (chain of TREE_LIST nodes
3626 with types in the TREE_VALUE slots), by adding the hash codes
3627 of the individual types. */
3630 type_hash_list (list)
3633 register int hashcode;
3635 for (hashcode = 0, tail = list; tail; tail = TREE_CHAIN (tail))
3636 hashcode += TYPE_HASH (TREE_VALUE (tail));
3640 /* Look in the type hash table for a type isomorphic to TYPE.
3641 If one is found, return it. Otherwise return 0. */
3644 type_hash_lookup (hashcode, type)
3648 register struct type_hash *h;
3649 for (h = type_hash_table[hashcode % TYPE_HASH_SIZE]; h; h = h->next)
3650 if (h->hashcode == hashcode
3651 && TREE_CODE (h->type) == TREE_CODE (type)
3652 && TREE_TYPE (h->type) == TREE_TYPE (type)
3653 && attribute_list_equal (TYPE_ATTRIBUTES (h->type),
3654 TYPE_ATTRIBUTES (type))
3655 && (TYPE_MAX_VALUE (h->type) == TYPE_MAX_VALUE (type)
3656 || tree_int_cst_equal (TYPE_MAX_VALUE (h->type),
3657 TYPE_MAX_VALUE (type)))
3658 && (TYPE_MIN_VALUE (h->type) == TYPE_MIN_VALUE (type)
3659 || tree_int_cst_equal (TYPE_MIN_VALUE (h->type),
3660 TYPE_MIN_VALUE (type)))
3661 /* Note that TYPE_DOMAIN is TYPE_ARG_TYPES for FUNCTION_TYPE. */
3662 && (TYPE_DOMAIN (h->type) == TYPE_DOMAIN (type)
3663 || (TYPE_DOMAIN (h->type)
3664 && TREE_CODE (TYPE_DOMAIN (h->type)) == TREE_LIST
3665 && TYPE_DOMAIN (type)
3666 && TREE_CODE (TYPE_DOMAIN (type)) == TREE_LIST
3667 && type_list_equal (TYPE_DOMAIN (h->type),
3668 TYPE_DOMAIN (type)))))
3673 /* Add an entry to the type-hash-table
3674 for a type TYPE whose hash code is HASHCODE. */
3677 type_hash_add (hashcode, type)
3681 register struct type_hash *h;
3683 h = (struct type_hash *) oballoc (sizeof (struct type_hash));
3684 h->hashcode = hashcode;
3686 h->next = type_hash_table[hashcode % TYPE_HASH_SIZE];
3687 type_hash_table[hashcode % TYPE_HASH_SIZE] = h;
3690 /* Given TYPE, and HASHCODE its hash code, return the canonical
3691 object for an identical type if one already exists.
3692 Otherwise, return TYPE, and record it as the canonical object
3693 if it is a permanent object.
3695 To use this function, first create a type of the sort you want.
3696 Then compute its hash code from the fields of the type that
3697 make it different from other similar types.
3698 Then call this function and use the value.
3699 This function frees the type you pass in if it is a duplicate. */
3701 /* Set to 1 to debug without canonicalization. Never set by program. */
3702 int debug_no_type_hash = 0;
3705 type_hash_canon (hashcode, type)
3711 if (debug_no_type_hash)
3714 t1 = type_hash_lookup (hashcode, type);
3717 obstack_free (TYPE_OBSTACK (type), type);
3718 #ifdef GATHER_STATISTICS
3719 tree_node_counts[(int)t_kind]--;
3720 tree_node_sizes[(int)t_kind] -= sizeof (struct tree_type);
3725 /* If this is a permanent type, record it for later reuse. */
3726 if (TREE_PERMANENT (type))
3727 type_hash_add (hashcode, type);
3732 /* Compute a hash code for a list of attributes (chain of TREE_LIST nodes
3733 with names in the TREE_PURPOSE slots and args in the TREE_VALUE slots),
3734 by adding the hash codes of the individual attributes. */
3737 attribute_hash_list (list)
3740 register int hashcode;
3742 for (hashcode = 0, tail = list; tail; tail = TREE_CHAIN (tail))
3743 /* ??? Do we want to add in TREE_VALUE too? */
3744 hashcode += TYPE_HASH (TREE_PURPOSE (tail));
3748 /* Given two lists of attributes, return true if list l2 is
3749 equivalent to l1. */
3752 attribute_list_equal (l1, l2)
3755 return attribute_list_contained (l1, l2)
3756 && attribute_list_contained (l2, l1);
3759 /* Given two lists of attributes, return true if list L2 is
3760 completely contained within L1. */
3761 /* ??? This would be faster if attribute names were stored in a canonicalized
3762 form. Otherwise, if L1 uses `foo' and L2 uses `__foo__', the long method
3763 must be used to show these elements are equivalent (which they are). */
3764 /* ??? It's not clear that attributes with arguments will always be handled
3768 attribute_list_contained (l1, l2)
3771 register tree t1, t2;
3773 /* First check the obvious, maybe the lists are identical. */
3777 /* Maybe the lists are similar. */
3778 for (t1 = l1, t2 = l2;
3780 && TREE_PURPOSE (t1) == TREE_PURPOSE (t2)
3781 && TREE_VALUE (t1) == TREE_VALUE (t2);
3782 t1 = TREE_CHAIN (t1), t2 = TREE_CHAIN (t2));
3784 /* Maybe the lists are equal. */
3785 if (t1 == 0 && t2 == 0)
3788 for (; t2; t2 = TREE_CHAIN (t2))
3791 = lookup_attribute (IDENTIFIER_POINTER (TREE_PURPOSE (t2)), l1);
3793 if (attr == NULL_TREE)
3795 if (simple_cst_equal (TREE_VALUE (t2), TREE_VALUE (attr)) != 1)
3802 /* Given two lists of types
3803 (chains of TREE_LIST nodes with types in the TREE_VALUE slots)
3804 return 1 if the lists contain the same types in the same order.
3805 Also, the TREE_PURPOSEs must match. */
3808 type_list_equal (l1, l2)
3811 register tree t1, t2;
3813 for (t1 = l1, t2 = l2; t1 && t2; t1 = TREE_CHAIN (t1), t2 = TREE_CHAIN (t2))
3814 if (TREE_VALUE (t1) != TREE_VALUE (t2)
3815 || (TREE_PURPOSE (t1) != TREE_PURPOSE (t2)
3816 && ! (1 == simple_cst_equal (TREE_PURPOSE (t1), TREE_PURPOSE (t2))
3817 && (TREE_TYPE (TREE_PURPOSE (t1))
3818 == TREE_TYPE (TREE_PURPOSE (t2))))))
3824 /* Nonzero if integer constants T1 and T2
3825 represent the same constant value. */
3828 tree_int_cst_equal (t1, t2)
3833 if (t1 == 0 || t2 == 0)
3835 if (TREE_CODE (t1) == INTEGER_CST
3836 && TREE_CODE (t2) == INTEGER_CST
3837 && TREE_INT_CST_LOW (t1) == TREE_INT_CST_LOW (t2)
3838 && TREE_INT_CST_HIGH (t1) == TREE_INT_CST_HIGH (t2))
3843 /* Nonzero if integer constants T1 and T2 represent values that satisfy <.
3844 The precise way of comparison depends on their data type. */
3847 tree_int_cst_lt (t1, t2)
3853 if (!TREE_UNSIGNED (TREE_TYPE (t1)))
3854 return INT_CST_LT (t1, t2);
3855 return INT_CST_LT_UNSIGNED (t1, t2);
3858 /* Return an indication of the sign of the integer constant T.
3859 The return value is -1 if T < 0, 0 if T == 0, and 1 if T > 0.
3860 Note that -1 will never be returned it T's type is unsigned. */
3863 tree_int_cst_sgn (t)
3866 if (TREE_INT_CST_LOW (t) == 0 && TREE_INT_CST_HIGH (t) == 0)
3868 else if (TREE_UNSIGNED (TREE_TYPE (t)))
3870 else if (TREE_INT_CST_HIGH (t) < 0)
3876 /* Compare two constructor-element-type constants. Return 1 if the lists
3877 are known to be equal; otherwise return 0. */
3880 simple_cst_list_equal (l1, l2)
3883 while (l1 != NULL_TREE && l2 != NULL_TREE)
3885 if (simple_cst_equal (TREE_VALUE (l1), TREE_VALUE (l2)) != 1)
3888 l1 = TREE_CHAIN (l1);
3889 l2 = TREE_CHAIN (l2);
3895 /* Return truthvalue of whether T1 is the same tree structure as T2.
3896 Return 1 if they are the same.
3897 Return 0 if they are understandably different.
3898 Return -1 if either contains tree structure not understood by
3902 simple_cst_equal (t1, t2)
3905 register enum tree_code code1, code2;
3910 if (t1 == 0 || t2 == 0)
3913 code1 = TREE_CODE (t1);
3914 code2 = TREE_CODE (t2);
3916 if (code1 == NOP_EXPR || code1 == CONVERT_EXPR || code1 == NON_LVALUE_EXPR)
3917 if (code2 == NOP_EXPR || code2 == CONVERT_EXPR || code2 == NON_LVALUE_EXPR)
3918 return simple_cst_equal (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0));
3920 return simple_cst_equal (TREE_OPERAND (t1, 0), t2);
3921 else if (code2 == NOP_EXPR || code2 == CONVERT_EXPR
3922 || code2 == NON_LVALUE_EXPR)
3923 return simple_cst_equal (t1, TREE_OPERAND (t2, 0));
3931 return TREE_INT_CST_LOW (t1) == TREE_INT_CST_LOW (t2)
3932 && TREE_INT_CST_HIGH (t1) == TREE_INT_CST_HIGH (t2);
3935 return REAL_VALUES_IDENTICAL (TREE_REAL_CST (t1), TREE_REAL_CST (t2));
3938 return TREE_STRING_LENGTH (t1) == TREE_STRING_LENGTH (t2)
3939 && !bcmp (TREE_STRING_POINTER (t1), TREE_STRING_POINTER (t2),
3940 TREE_STRING_LENGTH (t1));
3946 return simple_cst_equal (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0));
3949 cmp = simple_cst_equal (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0));
3952 return simple_cst_list_equal (TREE_OPERAND (t1, 1), TREE_OPERAND (t2, 1));
3955 /* Special case: if either target is an unallocated VAR_DECL,
3956 it means that it's going to be unified with whatever the
3957 TARGET_EXPR is really supposed to initialize, so treat it
3958 as being equivalent to anything. */
3959 if ((TREE_CODE (TREE_OPERAND (t1, 0)) == VAR_DECL
3960 && DECL_NAME (TREE_OPERAND (t1, 0)) == NULL_TREE
3961 && DECL_RTL (TREE_OPERAND (t1, 0)) == 0)
3962 || (TREE_CODE (TREE_OPERAND (t2, 0)) == VAR_DECL
3963 && DECL_NAME (TREE_OPERAND (t2, 0)) == NULL_TREE
3964 && DECL_RTL (TREE_OPERAND (t2, 0)) == 0))
3967 cmp = simple_cst_equal (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0));
3970 return simple_cst_equal (TREE_OPERAND (t1, 1), TREE_OPERAND (t2, 1));
3972 case WITH_CLEANUP_EXPR:
3973 cmp = simple_cst_equal (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0));
3976 return simple_cst_equal (TREE_OPERAND (t1, 2), TREE_OPERAND (t1, 2));
3979 if (TREE_OPERAND (t1, 1) == TREE_OPERAND (t2, 1))
3980 return simple_cst_equal (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0));
3993 /* This general rule works for most tree codes. All exceptions should be
3994 handled above. If this is a language-specific tree code, we can't
3995 trust what might be in the operand, so say we don't know
3997 if ((int) code1 >= (int) LAST_AND_UNUSED_TREE_CODE)
4000 switch (TREE_CODE_CLASS (code1))
4010 for (i=0; i<tree_code_length[(int) code1]; ++i)
4012 cmp = simple_cst_equal (TREE_OPERAND (t1, i), TREE_OPERAND (t2, i));
4023 /* Constructors for pointer, array and function types.
4024 (RECORD_TYPE, UNION_TYPE and ENUMERAL_TYPE nodes are
4025 constructed by language-dependent code, not here.) */
4027 /* Construct, lay out and return the type of pointers to TO_TYPE.
4028 If such a type has already been constructed, reuse it. */
4031 build_pointer_type (to_type)
4034 register tree t = TYPE_POINTER_TO (to_type);
4036 /* First, if we already have a type for pointers to TO_TYPE, use it. */
4041 /* We need a new one. Put this in the same obstack as TO_TYPE. */
4042 push_obstacks (TYPE_OBSTACK (to_type), TYPE_OBSTACK (to_type));
4043 t = make_node (POINTER_TYPE);
4046 TREE_TYPE (t) = to_type;
4048 /* Record this type as the pointer to TO_TYPE. */
4049 TYPE_POINTER_TO (to_type) = t;
4051 /* Lay out the type. This function has many callers that are concerned
4052 with expression-construction, and this simplifies them all.
4053 Also, it guarantees the TYPE_SIZE is in the same obstack as the type. */
4059 /* Create a type of integers to be the TYPE_DOMAIN of an ARRAY_TYPE.
4060 MAXVAL should be the maximum value in the domain
4061 (one less than the length of the array).
4063 The maximum value that MAXVAL can have is INT_MAX for a HOST_WIDE_INT.
4064 We don't enforce this limit, that is up to caller (e.g. language front end).
4065 The limit exists because the result is a signed type and we don't handle
4066 sizes that use more than one HOST_WIDE_INT. */
4069 build_index_type (maxval)
4072 register tree itype = make_node (INTEGER_TYPE);
4074 TYPE_PRECISION (itype) = TYPE_PRECISION (sizetype);
4075 TYPE_MIN_VALUE (itype) = size_zero_node;
4077 push_obstacks (TYPE_OBSTACK (itype), TYPE_OBSTACK (itype));
4078 TYPE_MAX_VALUE (itype) = convert (sizetype, maxval);
4081 TYPE_MODE (itype) = TYPE_MODE (sizetype);
4082 TYPE_SIZE (itype) = TYPE_SIZE (sizetype);
4083 TYPE_ALIGN (itype) = TYPE_ALIGN (sizetype);
4084 if (TREE_CODE (maxval) == INTEGER_CST)
4086 int maxint = (int) TREE_INT_CST_LOW (maxval);
4087 /* If the domain should be empty, make sure the maxval
4088 remains -1 and is not spoiled by truncation. */
4089 if (INT_CST_LT (maxval, integer_zero_node))
4091 TYPE_MAX_VALUE (itype) = build_int_2 (-1, -1);
4092 TREE_TYPE (TYPE_MAX_VALUE (itype)) = sizetype;
4094 return type_hash_canon (maxint < 0 ? ~maxint : maxint, itype);
4100 /* Create a range of some discrete type TYPE (an INTEGER_TYPE,
4101 ENUMERAL_TYPE, BOOLEAN_TYPE, or CHAR_TYPE), with
4102 low bound LOWVAL and high bound HIGHVAL.
4103 if TYPE==NULL_TREE, sizetype is used. */
4106 build_range_type (type, lowval, highval)
4107 tree type, lowval, highval;
4109 register tree itype = make_node (INTEGER_TYPE);
4111 TREE_TYPE (itype) = type;
4112 if (type == NULL_TREE)
4115 push_obstacks (TYPE_OBSTACK (itype), TYPE_OBSTACK (itype));
4116 TYPE_MIN_VALUE (itype) = convert (type, lowval);
4117 TYPE_MAX_VALUE (itype) = highval ? convert (type, highval) : NULL;
4120 TYPE_PRECISION (itype) = TYPE_PRECISION (type);
4121 TYPE_MODE (itype) = TYPE_MODE (type);
4122 TYPE_SIZE (itype) = TYPE_SIZE (type);
4123 TYPE_ALIGN (itype) = TYPE_ALIGN (type);
4124 if (TREE_CODE (lowval) == INTEGER_CST)
4126 HOST_WIDE_INT lowint, highint;
4129 lowint = TREE_INT_CST_LOW (lowval);
4130 if (highval && TREE_CODE (highval) == INTEGER_CST)
4131 highint = TREE_INT_CST_LOW (highval);
4133 highint = (~(unsigned HOST_WIDE_INT)0) >> 1;
4135 maxint = (int) (highint - lowint);
4136 return type_hash_canon (maxint < 0 ? ~maxint : maxint, itype);
4142 /* Just like build_index_type, but takes lowval and highval instead
4143 of just highval (maxval). */
4146 build_index_2_type (lowval,highval)
4147 tree lowval, highval;
4149 return build_range_type (NULL_TREE, lowval, highval);
4152 /* Return nonzero iff ITYPE1 and ITYPE2 are equal (in the LISP sense).
4153 Needed because when index types are not hashed, equal index types
4154 built at different times appear distinct, even though structurally,
4158 index_type_equal (itype1, itype2)
4159 tree itype1, itype2;
4161 if (TREE_CODE (itype1) != TREE_CODE (itype2))
4163 if (TREE_CODE (itype1) == INTEGER_TYPE)
4165 if (TYPE_PRECISION (itype1) != TYPE_PRECISION (itype2)
4166 || TYPE_MODE (itype1) != TYPE_MODE (itype2)
4167 || simple_cst_equal (TYPE_SIZE (itype1), TYPE_SIZE (itype2)) != 1
4168 || TYPE_ALIGN (itype1) != TYPE_ALIGN (itype2))
4170 if (1 == simple_cst_equal (TYPE_MIN_VALUE (itype1),
4171 TYPE_MIN_VALUE (itype2))
4172 && 1 == simple_cst_equal (TYPE_MAX_VALUE (itype1),
4173 TYPE_MAX_VALUE (itype2)))
4180 /* Construct, lay out and return the type of arrays of elements with ELT_TYPE
4181 and number of elements specified by the range of values of INDEX_TYPE.
4182 If such a type has already been constructed, reuse it. */
4185 build_array_type (elt_type, index_type)
4186 tree elt_type, index_type;
4191 if (TREE_CODE (elt_type) == FUNCTION_TYPE)
4193 error ("arrays of functions are not meaningful");
4194 elt_type = integer_type_node;
4197 /* Make sure TYPE_POINTER_TO (elt_type) is filled in. */
4198 build_pointer_type (elt_type);
4200 /* Allocate the array after the pointer type,
4201 in case we free it in type_hash_canon. */
4202 t = make_node (ARRAY_TYPE);
4203 TREE_TYPE (t) = elt_type;
4204 TYPE_DOMAIN (t) = index_type;
4206 if (index_type == 0)
4211 hashcode = TYPE_HASH (elt_type) + TYPE_HASH (index_type);
4212 t = type_hash_canon (hashcode, t);
4214 if (TYPE_SIZE (t) == 0)
4219 /* Construct, lay out and return
4220 the type of functions returning type VALUE_TYPE
4221 given arguments of types ARG_TYPES.
4222 ARG_TYPES is a chain of TREE_LIST nodes whose TREE_VALUEs
4223 are data type nodes for the arguments of the function.
4224 If such a type has already been constructed, reuse it. */
4227 build_function_type (value_type, arg_types)
4228 tree value_type, arg_types;
4233 if (TREE_CODE (value_type) == FUNCTION_TYPE)
4235 error ("function return type cannot be function");
4236 value_type = integer_type_node;
4239 /* Make a node of the sort we want. */
4240 t = make_node (FUNCTION_TYPE);
4241 TREE_TYPE (t) = value_type;
4242 TYPE_ARG_TYPES (t) = arg_types;
4244 /* If we already have such a type, use the old one and free this one. */
4245 hashcode = TYPE_HASH (value_type) + type_hash_list (arg_types);
4246 t = type_hash_canon (hashcode, t);
4248 if (TYPE_SIZE (t) == 0)
4253 /* Build the node for the type of references-to-TO_TYPE. */
4256 build_reference_type (to_type)
4259 register tree t = TYPE_REFERENCE_TO (to_type);
4260 register struct obstack *ambient_obstack = current_obstack;
4261 register struct obstack *ambient_saveable_obstack = saveable_obstack;
4263 /* First, if we already have a type for pointers to TO_TYPE, use it. */
4268 /* We need a new one. If TO_TYPE is permanent, make this permanent too. */
4269 if (TREE_PERMANENT (to_type))
4271 current_obstack = &permanent_obstack;
4272 saveable_obstack = &permanent_obstack;
4275 t = make_node (REFERENCE_TYPE);
4276 TREE_TYPE (t) = to_type;
4278 /* Record this type as the pointer to TO_TYPE. */
4279 TYPE_REFERENCE_TO (to_type) = t;
4283 current_obstack = ambient_obstack;
4284 saveable_obstack = ambient_saveable_obstack;
4288 /* Construct, lay out and return the type of methods belonging to class
4289 BASETYPE and whose arguments and values are described by TYPE.
4290 If that type exists already, reuse it.
4291 TYPE must be a FUNCTION_TYPE node. */
4294 build_method_type (basetype, type)
4295 tree basetype, type;
4300 /* Make a node of the sort we want. */
4301 t = make_node (METHOD_TYPE);
4303 if (TREE_CODE (type) != FUNCTION_TYPE)
4306 TYPE_METHOD_BASETYPE (t) = TYPE_MAIN_VARIANT (basetype);
4307 TREE_TYPE (t) = TREE_TYPE (type);
4309 /* The actual arglist for this function includes a "hidden" argument
4310 which is "this". Put it into the list of argument types. */
4313 = tree_cons (NULL_TREE,
4314 build_pointer_type (basetype), TYPE_ARG_TYPES (type));
4316 /* If we already have such a type, use the old one and free this one. */
4317 hashcode = TYPE_HASH (basetype) + TYPE_HASH (type);
4318 t = type_hash_canon (hashcode, t);
4320 if (TYPE_SIZE (t) == 0)
4326 /* Construct, lay out and return the type of offsets to a value
4327 of type TYPE, within an object of type BASETYPE.
4328 If a suitable offset type exists already, reuse it. */
4331 build_offset_type (basetype, type)
4332 tree basetype, type;
4337 /* Make a node of the sort we want. */
4338 t = make_node (OFFSET_TYPE);
4340 TYPE_OFFSET_BASETYPE (t) = TYPE_MAIN_VARIANT (basetype);
4341 TREE_TYPE (t) = type;
4343 /* If we already have such a type, use the old one and free this one. */
4344 hashcode = TYPE_HASH (basetype) + TYPE_HASH (type);
4345 t = type_hash_canon (hashcode, t);
4347 if (TYPE_SIZE (t) == 0)
4353 /* Create a complex type whose components are COMPONENT_TYPE. */
4356 build_complex_type (component_type)
4357 tree component_type;
4362 /* Make a node of the sort we want. */
4363 t = make_node (COMPLEX_TYPE);
4365 TREE_TYPE (t) = TYPE_MAIN_VARIANT (component_type);
4366 TYPE_VOLATILE (t) = TYPE_VOLATILE (component_type);
4367 TYPE_READONLY (t) = TYPE_READONLY (component_type);
4369 /* If we already have such a type, use the old one and free this one. */
4370 hashcode = TYPE_HASH (component_type);
4371 t = type_hash_canon (hashcode, t);
4373 if (TYPE_SIZE (t) == 0)
4379 /* Return OP, stripped of any conversions to wider types as much as is safe.
4380 Converting the value back to OP's type makes a value equivalent to OP.
4382 If FOR_TYPE is nonzero, we return a value which, if converted to
4383 type FOR_TYPE, would be equivalent to converting OP to type FOR_TYPE.
4385 If FOR_TYPE is nonzero, unaligned bit-field references may be changed to the
4386 narrowest type that can hold the value, even if they don't exactly fit.
4387 Otherwise, bit-field references are changed to a narrower type
4388 only if they can be fetched directly from memory in that type.
4390 OP must have integer, real or enumeral type. Pointers are not allowed!
4392 There are some cases where the obvious value we could return
4393 would regenerate to OP if converted to OP's type,
4394 but would not extend like OP to wider types.
4395 If FOR_TYPE indicates such extension is contemplated, we eschew such values.
4396 For example, if OP is (unsigned short)(signed char)-1,
4397 we avoid returning (signed char)-1 if FOR_TYPE is int,
4398 even though extending that to an unsigned short would regenerate OP,
4399 since the result of extending (signed char)-1 to (int)
4400 is different from (int) OP. */
4403 get_unwidened (op, for_type)
4407 /* Set UNS initially if converting OP to FOR_TYPE is a zero-extension. */
4408 /* TYPE_PRECISION is safe in place of type_precision since
4409 pointer types are not allowed. */
4410 register tree type = TREE_TYPE (op);
4411 register unsigned final_prec
4412 = TYPE_PRECISION (for_type != 0 ? for_type : type);
4414 = (for_type != 0 && for_type != type
4415 && final_prec > TYPE_PRECISION (type)
4416 && TREE_UNSIGNED (type));
4417 register tree win = op;
4419 while (TREE_CODE (op) == NOP_EXPR)
4421 register int bitschange
4422 = TYPE_PRECISION (TREE_TYPE (op))
4423 - TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (op, 0)));
4425 /* Truncations are many-one so cannot be removed.
4426 Unless we are later going to truncate down even farther. */
4428 && final_prec > TYPE_PRECISION (TREE_TYPE (op)))
4431 /* See what's inside this conversion. If we decide to strip it,
4433 op = TREE_OPERAND (op, 0);
4435 /* If we have not stripped any zero-extensions (uns is 0),
4436 we can strip any kind of extension.
4437 If we have previously stripped a zero-extension,
4438 only zero-extensions can safely be stripped.
4439 Any extension can be stripped if the bits it would produce
4440 are all going to be discarded later by truncating to FOR_TYPE. */
4444 if (! uns || final_prec <= TYPE_PRECISION (TREE_TYPE (op)))
4446 /* TREE_UNSIGNED says whether this is a zero-extension.
4447 Let's avoid computing it if it does not affect WIN
4448 and if UNS will not be needed again. */
4449 if ((uns || TREE_CODE (op) == NOP_EXPR)
4450 && TREE_UNSIGNED (TREE_TYPE (op)))
4458 if (TREE_CODE (op) == COMPONENT_REF
4459 /* Since type_for_size always gives an integer type. */
4460 && TREE_CODE (type) != REAL_TYPE
4461 /* Don't crash if field not laid out yet. */
4462 && DECL_SIZE (TREE_OPERAND (op, 1)) != 0)
4464 unsigned innerprec = TREE_INT_CST_LOW (DECL_SIZE (TREE_OPERAND (op, 1)));
4465 type = type_for_size (innerprec, TREE_UNSIGNED (TREE_OPERAND (op, 1)));
4467 /* We can get this structure field in the narrowest type it fits in.
4468 If FOR_TYPE is 0, do this only for a field that matches the
4469 narrower type exactly and is aligned for it
4470 The resulting extension to its nominal type (a fullword type)
4471 must fit the same conditions as for other extensions. */
4473 if (innerprec < TYPE_PRECISION (TREE_TYPE (op))
4474 && (for_type || ! DECL_BIT_FIELD (TREE_OPERAND (op, 1)))
4475 && (! uns || final_prec <= innerprec
4476 || TREE_UNSIGNED (TREE_OPERAND (op, 1)))
4479 win = build (COMPONENT_REF, type, TREE_OPERAND (op, 0),
4480 TREE_OPERAND (op, 1));
4481 TREE_SIDE_EFFECTS (win) = TREE_SIDE_EFFECTS (op);
4482 TREE_THIS_VOLATILE (win) = TREE_THIS_VOLATILE (op);
4483 TREE_RAISES (win) = TREE_RAISES (op);
4489 /* Return OP or a simpler expression for a narrower value
4490 which can be sign-extended or zero-extended to give back OP.
4491 Store in *UNSIGNEDP_PTR either 1 if the value should be zero-extended
4492 or 0 if the value should be sign-extended. */
4495 get_narrower (op, unsignedp_ptr)
4499 register int uns = 0;
4501 register tree win = op;
4503 while (TREE_CODE (op) == NOP_EXPR)
4505 register int bitschange
4506 = TYPE_PRECISION (TREE_TYPE (op))
4507 - TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (op, 0)));
4509 /* Truncations are many-one so cannot be removed. */
4513 /* See what's inside this conversion. If we decide to strip it,
4515 op = TREE_OPERAND (op, 0);
4519 /* An extension: the outermost one can be stripped,
4520 but remember whether it is zero or sign extension. */
4522 uns = TREE_UNSIGNED (TREE_TYPE (op));
4523 /* Otherwise, if a sign extension has been stripped,
4524 only sign extensions can now be stripped;
4525 if a zero extension has been stripped, only zero-extensions. */
4526 else if (uns != TREE_UNSIGNED (TREE_TYPE (op)))
4530 else /* bitschange == 0 */
4532 /* A change in nominal type can always be stripped, but we must
4533 preserve the unsignedness. */
4535 uns = TREE_UNSIGNED (TREE_TYPE (op));
4542 if (TREE_CODE (op) == COMPONENT_REF
4543 /* Since type_for_size always gives an integer type. */
4544 && TREE_CODE (TREE_TYPE (op)) != REAL_TYPE)
4546 unsigned innerprec = TREE_INT_CST_LOW (DECL_SIZE (TREE_OPERAND (op, 1)));
4547 tree type = type_for_size (innerprec, TREE_UNSIGNED (op));
4549 /* We can get this structure field in a narrower type that fits it,
4550 but the resulting extension to its nominal type (a fullword type)
4551 must satisfy the same conditions as for other extensions.
4553 Do this only for fields that are aligned (not bit-fields),
4554 because when bit-field insns will be used there is no
4555 advantage in doing this. */
4557 if (innerprec < TYPE_PRECISION (TREE_TYPE (op))
4558 && ! DECL_BIT_FIELD (TREE_OPERAND (op, 1))
4559 && (first || uns == TREE_UNSIGNED (TREE_OPERAND (op, 1)))
4563 uns = TREE_UNSIGNED (TREE_OPERAND (op, 1));
4564 win = build (COMPONENT_REF, type, TREE_OPERAND (op, 0),
4565 TREE_OPERAND (op, 1));
4566 TREE_SIDE_EFFECTS (win) = TREE_SIDE_EFFECTS (op);
4567 TREE_THIS_VOLATILE (win) = TREE_THIS_VOLATILE (op);
4568 TREE_RAISES (win) = TREE_RAISES (op);
4571 *unsignedp_ptr = uns;
4575 /* Return the precision of a type, for arithmetic purposes.
4576 Supports all types on which arithmetic is possible
4577 (including pointer types).
4578 It's not clear yet what will be right for complex types. */
4581 type_precision (type)
4584 return ((TREE_CODE (type) == INTEGER_TYPE
4585 || TREE_CODE (type) == ENUMERAL_TYPE
4586 || TREE_CODE (type) == REAL_TYPE)
4587 ? TYPE_PRECISION (type) : POINTER_SIZE);
4590 /* Nonzero if integer constant C has a value that is permissible
4591 for type TYPE (an INTEGER_TYPE). */
4594 int_fits_type_p (c, type)
4597 if (TREE_UNSIGNED (type))
4598 return (! (TREE_CODE (TYPE_MAX_VALUE (type)) == INTEGER_CST
4599 && INT_CST_LT_UNSIGNED (TYPE_MAX_VALUE (type), c))
4600 && ! (TREE_CODE (TYPE_MIN_VALUE (type)) == INTEGER_CST
4601 && INT_CST_LT_UNSIGNED (c, TYPE_MIN_VALUE (type)))
4602 /* Negative ints never fit unsigned types. */
4603 && ! (TREE_INT_CST_HIGH (c) < 0
4604 && ! TREE_UNSIGNED (TREE_TYPE (c))));
4606 return (! (TREE_CODE (TYPE_MAX_VALUE (type)) == INTEGER_CST
4607 && INT_CST_LT (TYPE_MAX_VALUE (type), c))
4608 && ! (TREE_CODE (TYPE_MIN_VALUE (type)) == INTEGER_CST
4609 && INT_CST_LT (c, TYPE_MIN_VALUE (type)))
4610 /* Unsigned ints with top bit set never fit signed types. */
4611 && ! (TREE_INT_CST_HIGH (c) < 0
4612 && TREE_UNSIGNED (TREE_TYPE (c))));
4615 /* Return the innermost context enclosing DECL that is
4616 a FUNCTION_DECL, or zero if none. */
4619 decl_function_context (decl)
4624 if (TREE_CODE (decl) == ERROR_MARK)
4627 if (TREE_CODE (decl) == SAVE_EXPR)
4628 context = SAVE_EXPR_CONTEXT (decl);
4630 context = DECL_CONTEXT (decl);
4632 while (context && TREE_CODE (context) != FUNCTION_DECL)
4634 if (TREE_CODE (context) == RECORD_TYPE
4635 || TREE_CODE (context) == UNION_TYPE
4636 || TREE_CODE (context) == QUAL_UNION_TYPE)
4637 context = TYPE_CONTEXT (context);
4638 else if (TREE_CODE (context) == TYPE_DECL)
4639 context = DECL_CONTEXT (context);
4640 else if (TREE_CODE (context) == BLOCK)
4641 context = BLOCK_SUPERCONTEXT (context);
4643 /* Unhandled CONTEXT !? */
4650 /* Return the innermost context enclosing DECL that is
4651 a RECORD_TYPE, UNION_TYPE or QUAL_UNION_TYPE, or zero if none.
4652 TYPE_DECLs and FUNCTION_DECLs are transparent to this function. */
4655 decl_type_context (decl)
4658 tree context = DECL_CONTEXT (decl);
4662 if (TREE_CODE (context) == RECORD_TYPE
4663 || TREE_CODE (context) == UNION_TYPE
4664 || TREE_CODE (context) == QUAL_UNION_TYPE)
4666 if (TREE_CODE (context) == TYPE_DECL
4667 || TREE_CODE (context) == FUNCTION_DECL)
4668 context = DECL_CONTEXT (context);
4669 else if (TREE_CODE (context) == BLOCK)
4670 context = BLOCK_SUPERCONTEXT (context);
4672 /* Unhandled CONTEXT!? */
4678 /* Print debugging information about the size of the
4679 toplev_inline_obstacks. */
4682 print_inline_obstack_statistics ()
4684 struct simple_obstack_stack *current = toplev_inline_obstacks;
4689 for (; current; current = current->next, ++n_obstacks)
4691 struct obstack *o = current->obstack;
4692 struct _obstack_chunk *chunk = o->chunk;
4694 n_alloc += o->next_free - chunk->contents;
4695 chunk = chunk->prev;
4697 for (; chunk; chunk = chunk->prev, ++n_chunks)
4698 n_alloc += chunk->limit - &chunk->contents[0];
4700 fprintf (stderr, "inline obstacks: %d obstacks, %d bytes, %d chunks\n",
4701 n_obstacks, n_alloc, n_chunks);
4704 /* Print debugging information about the obstack O, named STR. */
4707 print_obstack_statistics (str, o)
4711 struct _obstack_chunk *chunk = o->chunk;
4715 n_alloc += o->next_free - chunk->contents;
4716 chunk = chunk->prev;
4720 n_alloc += chunk->limit - &chunk->contents[0];
4721 chunk = chunk->prev;
4723 fprintf (stderr, "obstack %s: %u bytes, %d chunks\n",
4724 str, n_alloc, n_chunks);
4727 /* Print debugging information about tree nodes generated during the compile,
4728 and any language-specific information. */
4731 dump_tree_statistics ()
4733 #ifdef GATHER_STATISTICS
4735 int total_nodes, total_bytes;
4738 fprintf (stderr, "\n??? tree nodes created\n\n");
4739 #ifdef GATHER_STATISTICS
4740 fprintf (stderr, "Kind Nodes Bytes\n");
4741 fprintf (stderr, "-------------------------------------\n");
4742 total_nodes = total_bytes = 0;
4743 for (i = 0; i < (int) all_kinds; i++)
4745 fprintf (stderr, "%-20s %6d %9d\n", tree_node_kind_names[i],
4746 tree_node_counts[i], tree_node_sizes[i]);
4747 total_nodes += tree_node_counts[i];
4748 total_bytes += tree_node_sizes[i];
4750 fprintf (stderr, "%-20s %9d\n", "identifier names", id_string_size);
4751 fprintf (stderr, "-------------------------------------\n");
4752 fprintf (stderr, "%-20s %6d %9d\n", "Total", total_nodes, total_bytes);
4753 fprintf (stderr, "-------------------------------------\n");
4755 fprintf (stderr, "(No per-node statistics)\n");
4757 print_obstack_statistics ("permanent_obstack", &permanent_obstack);
4758 print_obstack_statistics ("maybepermanent_obstack", &maybepermanent_obstack);
4759 print_obstack_statistics ("temporary_obstack", &temporary_obstack);
4760 print_obstack_statistics ("momentary_obstack", &momentary_obstack);
4761 print_obstack_statistics ("temp_decl_obstack", &temp_decl_obstack);
4762 print_inline_obstack_statistics ();
4763 print_lang_statistics ();
4766 #define FILE_FUNCTION_PREFIX_LEN 9
4768 #ifndef NO_DOLLAR_IN_LABEL
4769 #define FILE_FUNCTION_FORMAT "_GLOBAL_$D$%s"
4770 #else /* NO_DOLLAR_IN_LABEL */
4771 #ifndef NO_DOT_IN_LABEL
4772 #define FILE_FUNCTION_FORMAT "_GLOBAL_.D.%s"
4773 #else /* NO_DOT_IN_LABEL */
4774 #define FILE_FUNCTION_FORMAT "_GLOBAL__D_%s"
4775 #endif /* NO_DOT_IN_LABEL */
4776 #endif /* NO_DOLLAR_IN_LABEL */
4778 extern char * first_global_object_name;
4780 /* If KIND=='I', return a suitable global initializer (constructor) name.
4781 If KIND=='D', return a suitable global clean-up (destructor) name. */
4784 get_file_function_name (kind)
4790 if (first_global_object_name)
4791 p = first_global_object_name;
4792 else if (main_input_filename)
4793 p = main_input_filename;
4797 buf = (char *) alloca (sizeof (FILE_FUNCTION_FORMAT) + strlen (p));
4799 /* Set up the name of the file-level functions we may need. */
4800 /* Use a global object (which is already required to be unique over
4801 the program) rather than the file name (which imposes extra
4802 constraints). -- Raeburn@MIT.EDU, 10 Jan 1990. */
4803 sprintf (buf, FILE_FUNCTION_FORMAT, p);
4805 /* Don't need to pull weird characters out of global names. */
4806 if (p != first_global_object_name)
4808 for (p = buf+11; *p; p++)
4809 if (! ((*p >= '0' && *p <= '9')
4810 #if 0 /* we always want labels, which are valid C++ identifiers (+ `$') */
4811 #ifndef ASM_IDENTIFY_GCC /* this is required if `.' is invalid -- k. raeburn */
4815 #ifndef NO_DOLLAR_IN_LABEL /* this for `$'; unlikely, but... -- kr */
4818 #ifndef NO_DOT_IN_LABEL /* this for `.'; unlikely, but... */
4821 || (*p >= 'A' && *p <= 'Z')
4822 || (*p >= 'a' && *p <= 'z')))
4826 buf[FILE_FUNCTION_PREFIX_LEN] = kind;
4828 return get_identifier (buf);
4831 /* Expand (the constant part of) a SET_TYPE CONSTRUCTOR node.
4832 The result is placed in BUFFER (which has length BIT_SIZE),
4833 with one bit in each char ('\000' or '\001').
4835 If the constructor is constant, NULL_TREE is returned.
4836 Otherwise, a TREE_LIST of the non-constant elements is emitted. */
4839 get_set_constructor_bits (init, buffer, bit_size)
4846 HOST_WIDE_INT domain_min
4847 = TREE_INT_CST_LOW (TYPE_MIN_VALUE (TYPE_DOMAIN (TREE_TYPE (init))));
4848 tree non_const_bits = NULL_TREE;
4849 for (i = 0; i < bit_size; i++)
4852 for (vals = TREE_OPERAND (init, 1);
4853 vals != NULL_TREE; vals = TREE_CHAIN (vals))
4855 if (TREE_CODE (TREE_VALUE (vals)) != INTEGER_CST
4856 || (TREE_PURPOSE (vals) != NULL_TREE
4857 && TREE_CODE (TREE_PURPOSE (vals)) != INTEGER_CST))
4859 = tree_cons (TREE_PURPOSE (vals), TREE_VALUE (vals), non_const_bits);
4860 else if (TREE_PURPOSE (vals) != NULL_TREE)
4862 /* Set a range of bits to ones. */
4863 HOST_WIDE_INT lo_index
4864 = TREE_INT_CST_LOW (TREE_PURPOSE (vals)) - domain_min;
4865 HOST_WIDE_INT hi_index
4866 = TREE_INT_CST_LOW (TREE_VALUE (vals)) - domain_min;
4867 if (lo_index < 0 || lo_index >= bit_size
4868 || hi_index < 0 || hi_index >= bit_size)
4870 for ( ; lo_index <= hi_index; lo_index++)
4871 buffer[lo_index] = 1;
4875 /* Set a single bit to one. */
4877 = TREE_INT_CST_LOW (TREE_VALUE (vals)) - domain_min;
4878 if (index < 0 || index >= bit_size)
4880 error ("invalid initializer for bit string");
4886 return non_const_bits;
4889 /* Expand (the constant part of) a SET_TYPE CONSTRUCTOR node.
4890 The result is placed in BUFFER (which is an array of bytes).
4891 If the constructor is constant, NULL_TREE is returned.
4892 Otherwise, a TREE_LIST of the non-constant elements is emitted. */
4895 get_set_constructor_bytes (init, buffer, wd_size)
4897 unsigned char *buffer;
4901 int set_word_size = BITS_PER_UNIT;
4902 int bit_size = wd_size * set_word_size;
4904 unsigned char *bytep = buffer;
4905 char *bit_buffer = (char *) alloca(bit_size);
4906 tree non_const_bits = get_set_constructor_bits (init, bit_buffer, bit_size);
4908 for (i = 0; i < wd_size; i++)
4911 for (i = 0; i < bit_size; i++)
4915 if (BYTES_BIG_ENDIAN)
4916 *bytep |= (1 << (set_word_size - 1 - bit_pos));
4918 *bytep |= 1 << bit_pos;
4921 if (bit_pos >= set_word_size)
4922 bit_pos = 0, bytep++;
4924 return non_const_bits;