1 /* Language-independent node constructors for parse phase of GNU compiler.
2 Copyright (C) 1987, 88, 92-96, 1997 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. */
50 #define obstack_chunk_alloc xmalloc
51 #define obstack_chunk_free free
53 /* Tree nodes of permanent duration are allocated in this obstack.
54 They are the identifier nodes, and everything outside of
55 the bodies and parameters of function definitions. */
57 struct obstack permanent_obstack;
59 /* The initial RTL, and all ..._TYPE nodes, in a function
60 are allocated in this obstack. Usually they are freed at the
61 end of the function, but if the function is inline they are saved.
62 For top-level functions, this is maybepermanent_obstack.
63 Separate obstacks are made for nested functions. */
65 struct obstack *function_maybepermanent_obstack;
67 /* This is the function_maybepermanent_obstack for top-level functions. */
69 struct obstack maybepermanent_obstack;
71 /* This is a list of function_maybepermanent_obstacks for top-level inline
72 functions that are compiled in the middle of compiling other functions. */
74 struct simple_obstack_stack *toplev_inline_obstacks;
76 /* This is a list of function_maybepermanent_obstacks for inline functions
77 nested in the current function that were compiled in the middle of
78 compiling other functions. */
80 struct simple_obstack_stack *inline_obstacks;
82 /* The contents of the current function definition are allocated
83 in this obstack, and all are freed at the end of the function.
84 For top-level functions, this is temporary_obstack.
85 Separate obstacks are made for nested functions. */
87 struct obstack *function_obstack;
89 /* This is used for reading initializers of global variables. */
91 struct obstack temporary_obstack;
93 /* The tree nodes of an expression are allocated
94 in this obstack, and all are freed at the end of the expression. */
96 struct obstack momentary_obstack;
98 /* The tree nodes of a declarator are allocated
99 in this obstack, and all are freed when the declarator
102 static struct obstack temp_decl_obstack;
104 /* This points at either permanent_obstack
105 or the current function_maybepermanent_obstack. */
107 struct obstack *saveable_obstack;
109 /* This is same as saveable_obstack during parse and expansion phase;
110 it points to the current function's obstack during optimization.
111 This is the obstack to be used for creating rtl objects. */
113 struct obstack *rtl_obstack;
115 /* This points at either permanent_obstack or the current function_obstack. */
117 struct obstack *current_obstack;
119 /* This points at either permanent_obstack or the current function_obstack
120 or momentary_obstack. */
122 struct obstack *expression_obstack;
124 /* Stack of obstack selections for push_obstacks and pop_obstacks. */
128 struct obstack_stack *next;
129 struct obstack *current;
130 struct obstack *saveable;
131 struct obstack *expression;
135 struct obstack_stack *obstack_stack;
137 /* Obstack for allocating struct obstack_stack entries. */
139 static struct obstack obstack_stack_obstack;
141 /* Addresses of first objects in some obstacks.
142 This is for freeing their entire contents. */
143 char *maybepermanent_firstobj;
144 char *temporary_firstobj;
145 char *momentary_firstobj;
146 char *temp_decl_firstobj;
148 /* This is used to preserve objects (mainly array initializers) that need to
149 live until the end of the current function, but no further. */
150 char *momentary_function_firstobj;
152 /* Nonzero means all ..._TYPE nodes should be allocated permanently. */
154 int all_types_permanent;
156 /* Stack of places to restore the momentary obstack back to. */
158 struct momentary_level
160 /* Pointer back to previous such level. */
161 struct momentary_level *prev;
162 /* First object allocated within this level. */
164 /* Value of expression_obstack saved at entry to this level. */
165 struct obstack *obstack;
168 struct momentary_level *momentary_stack;
170 /* Table indexed by tree code giving a string containing a character
171 classifying the tree code. Possibilities are
172 t, d, s, c, r, <, 1, 2 and e. See tree.def for details. */
174 #define DEFTREECODE(SYM, NAME, TYPE, LENGTH) TYPE,
176 char *standard_tree_code_type[] = {
181 /* Table indexed by tree code giving number of expression
182 operands beyond the fixed part of the node structure.
183 Not used for types or decls. */
185 #define DEFTREECODE(SYM, NAME, TYPE, LENGTH) LENGTH,
187 int standard_tree_code_length[] = {
192 /* Names of tree components.
193 Used for printing out the tree and error messages. */
194 #define DEFTREECODE(SYM, NAME, TYPE, LEN) NAME,
196 char *standard_tree_code_name[] = {
201 /* Table indexed by tree code giving a string containing a character
202 classifying the tree code. Possibilities are
203 t, d, s, c, r, e, <, 1 and 2. See tree.def for details. */
205 char **tree_code_type;
207 /* Table indexed by tree code giving number of expression
208 operands beyond the fixed part of the node structure.
209 Not used for types or decls. */
211 int *tree_code_length;
213 /* Table indexed by tree code giving name of tree code, as a string. */
215 char **tree_code_name;
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) ((HOST_WIDE_INT) (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 current = ((struct simple_obstack_stack *)
377 xmalloc (sizeof (struct simple_obstack_stack)));
379 current->obstack = (struct obstack *) xmalloc (sizeof (struct obstack));
380 function_maybepermanent_obstack = current->obstack;
381 gcc_obstack_init (function_maybepermanent_obstack);
383 current->next = *head;
387 maybepermanent_firstobj
388 = (char *) obstack_finish (function_maybepermanent_obstack);
390 function_obstack = (struct obstack *) xmalloc (sizeof (struct obstack));
391 gcc_obstack_init (function_obstack);
393 current_obstack = &permanent_obstack;
394 expression_obstack = &permanent_obstack;
395 rtl_obstack = saveable_obstack = &permanent_obstack;
397 temporary_firstobj = (char *) obstack_alloc (&temporary_obstack, 0);
398 momentary_firstobj = (char *) obstack_finish (&momentary_obstack);
399 momentary_function_firstobj = momentary_firstobj;
402 /* Restore all variables describing the current status from the structure *P.
403 This is used after a nested function. */
406 restore_tree_status (p)
409 all_types_permanent = p->all_types_permanent;
410 momentary_stack = p->momentary_stack;
412 obstack_free (&momentary_obstack, momentary_function_firstobj);
414 /* Free saveable storage used by the function just compiled and not
417 CAUTION: This is in function_obstack of the containing function.
418 So we must be sure that we never allocate from that obstack during
419 the compilation of a nested function if we expect it to survive
420 past the nested function's end. */
421 obstack_free (function_maybepermanent_obstack, maybepermanent_firstobj);
423 obstack_free (function_obstack, 0);
424 free (function_obstack);
426 temporary_firstobj = p->temporary_firstobj;
427 momentary_firstobj = p->momentary_firstobj;
428 momentary_function_firstobj = p->momentary_function_firstobj;
429 maybepermanent_firstobj = p->maybepermanent_firstobj;
430 function_obstack = p->function_obstack;
431 function_maybepermanent_obstack = p->function_maybepermanent_obstack;
432 current_obstack = p->current_obstack;
433 expression_obstack = p->expression_obstack;
434 saveable_obstack = p->saveable_obstack;
435 rtl_obstack = p->rtl_obstack;
436 inline_obstacks = p->inline_obstacks;
439 /* Start allocating on the temporary (per function) obstack.
440 This is done in start_function before parsing the function body,
441 and before each initialization at top level, and to go back
442 to temporary allocation after doing permanent_allocation. */
445 temporary_allocation ()
447 /* Note that function_obstack at top level points to temporary_obstack.
448 But within a nested function context, it is a separate obstack. */
449 current_obstack = function_obstack;
450 expression_obstack = function_obstack;
451 rtl_obstack = saveable_obstack = function_maybepermanent_obstack;
456 /* Start allocating on the permanent obstack but don't
457 free the temporary data. After calling this, call
458 `permanent_allocation' to fully resume permanent allocation status. */
461 end_temporary_allocation ()
463 current_obstack = &permanent_obstack;
464 expression_obstack = &permanent_obstack;
465 rtl_obstack = saveable_obstack = &permanent_obstack;
468 /* Resume allocating on the temporary obstack, undoing
469 effects of `end_temporary_allocation'. */
472 resume_temporary_allocation ()
474 current_obstack = function_obstack;
475 expression_obstack = function_obstack;
476 rtl_obstack = saveable_obstack = function_maybepermanent_obstack;
479 /* While doing temporary allocation, switch to allocating in such a
480 way as to save all nodes if the function is inlined. Call
481 resume_temporary_allocation to go back to ordinary temporary
485 saveable_allocation ()
487 /* Note that function_obstack at top level points to temporary_obstack.
488 But within a nested function context, it is a separate obstack. */
489 expression_obstack = current_obstack = saveable_obstack;
492 /* Switch to current obstack CURRENT and maybepermanent obstack SAVEABLE,
493 recording the previously current obstacks on a stack.
494 This does not free any storage in any obstack. */
497 push_obstacks (current, saveable)
498 struct obstack *current, *saveable;
500 struct obstack_stack *p
501 = (struct obstack_stack *) obstack_alloc (&obstack_stack_obstack,
502 (sizeof (struct obstack_stack)));
504 p->current = current_obstack;
505 p->saveable = saveable_obstack;
506 p->expression = expression_obstack;
507 p->rtl = rtl_obstack;
508 p->next = obstack_stack;
511 current_obstack = current;
512 expression_obstack = current;
513 rtl_obstack = saveable_obstack = saveable;
516 /* Save the current set of obstacks, but don't change them. */
519 push_obstacks_nochange ()
521 struct obstack_stack *p
522 = (struct obstack_stack *) obstack_alloc (&obstack_stack_obstack,
523 (sizeof (struct obstack_stack)));
525 p->current = current_obstack;
526 p->saveable = saveable_obstack;
527 p->expression = expression_obstack;
528 p->rtl = rtl_obstack;
529 p->next = obstack_stack;
533 /* Pop the obstack selection stack. */
538 struct obstack_stack *p = obstack_stack;
539 obstack_stack = p->next;
541 current_obstack = p->current;
542 saveable_obstack = p->saveable;
543 expression_obstack = p->expression;
544 rtl_obstack = p->rtl;
546 obstack_free (&obstack_stack_obstack, p);
549 /* Nonzero if temporary allocation is currently in effect.
550 Zero if currently doing permanent allocation. */
553 allocation_temporary_p ()
555 return current_obstack != &permanent_obstack;
558 /* Go back to allocating on the permanent obstack
559 and free everything in the temporary obstack.
561 FUNCTION_END is true only if we have just finished compiling a function.
562 In that case, we also free preserved initial values on the momentary
566 permanent_allocation (function_end)
569 /* Free up previous temporary obstack data */
570 obstack_free (&temporary_obstack, temporary_firstobj);
573 obstack_free (&momentary_obstack, momentary_function_firstobj);
574 momentary_firstobj = momentary_function_firstobj;
577 obstack_free (&momentary_obstack, momentary_firstobj);
578 obstack_free (function_maybepermanent_obstack, maybepermanent_firstobj);
579 obstack_free (&temp_decl_obstack, temp_decl_firstobj);
581 /* Free up the maybepermanent_obstacks for any of our nested functions
582 which were compiled at a lower level. */
583 while (inline_obstacks)
585 struct simple_obstack_stack *current = inline_obstacks;
586 inline_obstacks = current->next;
587 obstack_free (current->obstack, 0);
588 free (current->obstack);
592 current_obstack = &permanent_obstack;
593 expression_obstack = &permanent_obstack;
594 rtl_obstack = saveable_obstack = &permanent_obstack;
597 /* Save permanently everything on the maybepermanent_obstack. */
602 maybepermanent_firstobj
603 = (char *) obstack_alloc (function_maybepermanent_obstack, 0);
607 preserve_initializer ()
609 struct momentary_level *tem;
613 = (char *) obstack_alloc (&temporary_obstack, 0);
614 maybepermanent_firstobj
615 = (char *) obstack_alloc (function_maybepermanent_obstack, 0);
617 old_momentary = momentary_firstobj;
619 = (char *) obstack_alloc (&momentary_obstack, 0);
620 if (momentary_firstobj != old_momentary)
621 for (tem = momentary_stack; tem; tem = tem->prev)
622 tem->base = momentary_firstobj;
625 /* Start allocating new rtl in current_obstack.
626 Use resume_temporary_allocation
627 to go back to allocating rtl in saveable_obstack. */
630 rtl_in_current_obstack ()
632 rtl_obstack = current_obstack;
635 /* Start allocating rtl from saveable_obstack. Intended to be used after
636 a call to push_obstacks_nochange. */
639 rtl_in_saveable_obstack ()
641 rtl_obstack = saveable_obstack;
644 /* Allocate SIZE bytes in the current obstack
645 and return a pointer to them.
646 In practice the current obstack is always the temporary one. */
652 return (char *) obstack_alloc (current_obstack, size);
655 /* Free the object PTR in the current obstack
656 as well as everything allocated since PTR.
657 In practice the current obstack is always the temporary one. */
663 obstack_free (current_obstack, ptr);
666 /* Allocate SIZE bytes in the permanent obstack
667 and return a pointer to them. */
673 return (char *) obstack_alloc (&permanent_obstack, size);
676 /* Allocate NELEM items of SIZE bytes in the permanent obstack
677 and return a pointer to them. The storage is cleared before
678 returning the value. */
681 perm_calloc (nelem, size)
685 char *rval = (char *) obstack_alloc (&permanent_obstack, nelem * size);
686 bzero (rval, nelem * size);
690 /* Allocate SIZE bytes in the saveable obstack
691 and return a pointer to them. */
697 return (char *) obstack_alloc (saveable_obstack, size);
700 /* Print out which obstack an object is in. */
703 print_obstack_name (object, file, prefix)
708 struct obstack *obstack = NULL;
709 char *obstack_name = NULL;
712 for (p = outer_function_chain; p; p = p->next)
714 if (_obstack_allocated_p (p->function_obstack, object))
716 obstack = p->function_obstack;
717 obstack_name = "containing function obstack";
719 if (_obstack_allocated_p (p->function_maybepermanent_obstack, object))
721 obstack = p->function_maybepermanent_obstack;
722 obstack_name = "containing function maybepermanent obstack";
726 if (_obstack_allocated_p (&obstack_stack_obstack, object))
728 obstack = &obstack_stack_obstack;
729 obstack_name = "obstack_stack_obstack";
731 else if (_obstack_allocated_p (function_obstack, object))
733 obstack = function_obstack;
734 obstack_name = "function obstack";
736 else if (_obstack_allocated_p (&permanent_obstack, object))
738 obstack = &permanent_obstack;
739 obstack_name = "permanent_obstack";
741 else if (_obstack_allocated_p (&momentary_obstack, object))
743 obstack = &momentary_obstack;
744 obstack_name = "momentary_obstack";
746 else if (_obstack_allocated_p (function_maybepermanent_obstack, object))
748 obstack = function_maybepermanent_obstack;
749 obstack_name = "function maybepermanent obstack";
751 else if (_obstack_allocated_p (&temp_decl_obstack, object))
753 obstack = &temp_decl_obstack;
754 obstack_name = "temp_decl_obstack";
757 /* Check to see if the object is in the free area of the obstack. */
760 if (object >= obstack->next_free
761 && object < obstack->chunk_limit)
762 fprintf (file, "%s in free portion of obstack %s",
763 prefix, obstack_name);
765 fprintf (file, "%s allocated from %s", prefix, obstack_name);
768 fprintf (file, "%s not allocated from any obstack", prefix);
772 debug_obstack (object)
775 print_obstack_name (object, stderr, "object");
776 fprintf (stderr, ".\n");
779 /* Return 1 if OBJ is in the permanent obstack.
780 This is slow, and should be used only for debugging.
781 Use TREE_PERMANENT for other purposes. */
784 object_permanent_p (obj)
787 return _obstack_allocated_p (&permanent_obstack, obj);
790 /* Start a level of momentary allocation.
791 In C, each compound statement has its own level
792 and that level is freed at the end of each statement.
793 All expression nodes are allocated in the momentary allocation level. */
798 struct momentary_level *tem
799 = (struct momentary_level *) obstack_alloc (&momentary_obstack,
800 sizeof (struct momentary_level));
801 tem->prev = momentary_stack;
802 tem->base = (char *) obstack_base (&momentary_obstack);
803 tem->obstack = expression_obstack;
804 momentary_stack = tem;
805 expression_obstack = &momentary_obstack;
808 /* Set things up so the next clear_momentary will only clear memory
809 past our present position in momentary_obstack. */
812 preserve_momentary ()
814 momentary_stack->base = (char *) obstack_base (&momentary_obstack);
817 /* Free all the storage in the current momentary-allocation level.
818 In C, this happens at the end of each statement. */
823 obstack_free (&momentary_obstack, momentary_stack->base);
826 /* Discard a level of momentary allocation.
827 In C, this happens at the end of each compound statement.
828 Restore the status of expression node allocation
829 that was in effect before this level was created. */
834 struct momentary_level *tem = momentary_stack;
835 momentary_stack = tem->prev;
836 expression_obstack = tem->obstack;
837 /* We can't free TEM from the momentary_obstack, because there might
838 be objects above it which have been saved. We can free back to the
839 stack of the level we are popping off though. */
840 obstack_free (&momentary_obstack, tem->base);
843 /* Pop back to the previous level of momentary allocation,
844 but don't free any momentary data just yet. */
847 pop_momentary_nofree ()
849 struct momentary_level *tem = momentary_stack;
850 momentary_stack = tem->prev;
851 expression_obstack = tem->obstack;
854 /* Call when starting to parse a declaration:
855 make expressions in the declaration last the length of the function.
856 Returns an argument that should be passed to resume_momentary later. */
861 register int tem = expression_obstack == &momentary_obstack;
862 expression_obstack = saveable_obstack;
866 /* Call when finished parsing a declaration:
867 restore the treatment of node-allocation that was
868 in effect before the suspension.
869 YES should be the value previously returned by suspend_momentary. */
872 resume_momentary (yes)
876 expression_obstack = &momentary_obstack;
879 /* Init the tables indexed by tree code.
880 Note that languages can add to these tables to define their own codes. */
885 tree_code_type = (char **) xmalloc (sizeof (standard_tree_code_type));
886 tree_code_length = (int *) xmalloc (sizeof (standard_tree_code_length));
887 tree_code_name = (char **) xmalloc (sizeof (standard_tree_code_name));
888 bcopy ((char *) standard_tree_code_type, (char *) tree_code_type,
889 sizeof (standard_tree_code_type));
890 bcopy ((char *) standard_tree_code_length, (char *) tree_code_length,
891 sizeof (standard_tree_code_length));
892 bcopy ((char *) standard_tree_code_name, (char *) tree_code_name,
893 sizeof (standard_tree_code_name));
896 /* Return a newly allocated node of code CODE.
897 Initialize the node's unique id and its TREE_PERMANENT flag.
898 For decl and type nodes, some other fields are initialized.
899 The rest of the node is initialized to zero.
901 Achoo! I got a code in the node. */
908 register int type = TREE_CODE_CLASS (code);
910 register struct obstack *obstack = current_obstack;
912 register tree_node_kind kind;
916 case 'd': /* A decl node */
917 #ifdef GATHER_STATISTICS
920 length = sizeof (struct tree_decl);
921 /* All decls in an inline function need to be saved. */
922 if (obstack != &permanent_obstack)
923 obstack = saveable_obstack;
925 /* PARM_DECLs go on the context of the parent. If this is a nested
926 function, then we must allocate the PARM_DECL on the parent's
927 obstack, so that they will live to the end of the parent's
928 closing brace. This is necessary in case we try to inline the
929 function into its parent.
931 PARM_DECLs of top-level functions do not have this problem. However,
932 we allocate them where we put the FUNCTION_DECL for languages such as
933 Ada that need to consult some flags in the PARM_DECLs of the function
936 See comment in restore_tree_status for why we can't put this
937 in function_obstack. */
938 if (code == PARM_DECL && obstack != &permanent_obstack)
941 if (current_function_decl)
942 context = decl_function_context (current_function_decl);
946 = find_function_data (context)->function_maybepermanent_obstack;
950 case 't': /* a type node */
951 #ifdef GATHER_STATISTICS
954 length = sizeof (struct tree_type);
955 /* All data types are put where we can preserve them if nec. */
956 if (obstack != &permanent_obstack)
957 obstack = all_types_permanent ? &permanent_obstack : saveable_obstack;
960 case 'b': /* a lexical block */
961 #ifdef GATHER_STATISTICS
964 length = sizeof (struct tree_block);
965 /* All BLOCK nodes are put where we can preserve them if nec. */
966 if (obstack != &permanent_obstack)
967 obstack = saveable_obstack;
970 case 's': /* an expression with side effects */
971 #ifdef GATHER_STATISTICS
975 case 'r': /* a reference */
976 #ifdef GATHER_STATISTICS
980 case 'e': /* an expression */
981 case '<': /* a comparison expression */
982 case '1': /* a unary arithmetic expression */
983 case '2': /* a binary arithmetic expression */
984 #ifdef GATHER_STATISTICS
988 obstack = expression_obstack;
989 /* All BIND_EXPR nodes are put where we can preserve them if nec. */
990 if (code == BIND_EXPR && obstack != &permanent_obstack)
991 obstack = saveable_obstack;
992 length = sizeof (struct tree_exp)
993 + (tree_code_length[(int) code] - 1) * sizeof (char *);
996 case 'c': /* a constant */
997 #ifdef GATHER_STATISTICS
1000 obstack = expression_obstack;
1002 /* We can't use tree_code_length for INTEGER_CST, since the number of
1003 words is machine-dependent due to varying length of HOST_WIDE_INT,
1004 which might be wider than a pointer (e.g., long long). Similarly
1005 for REAL_CST, since the number of words is machine-dependent due
1006 to varying size and alignment of `double'. */
1008 if (code == INTEGER_CST)
1009 length = sizeof (struct tree_int_cst);
1010 else if (code == REAL_CST)
1011 length = sizeof (struct tree_real_cst);
1013 length = sizeof (struct tree_common)
1014 + tree_code_length[(int) code] * sizeof (char *);
1017 case 'x': /* something random, like an identifier. */
1018 #ifdef GATHER_STATISTICS
1019 if (code == IDENTIFIER_NODE)
1021 else if (code == OP_IDENTIFIER)
1023 else if (code == TREE_VEC)
1028 length = sizeof (struct tree_common)
1029 + tree_code_length[(int) code] * sizeof (char *);
1030 /* Identifier nodes are always permanent since they are
1031 unique in a compiler run. */
1032 if (code == IDENTIFIER_NODE) obstack = &permanent_obstack;
1039 t = (tree) obstack_alloc (obstack, length);
1041 #ifdef GATHER_STATISTICS
1042 tree_node_counts[(int)kind]++;
1043 tree_node_sizes[(int)kind] += length;
1046 /* Clear a word at a time. */
1047 for (i = (length / sizeof (int)) - 1; i >= 0; i--)
1049 /* Clear any extra bytes. */
1050 for (i = length / sizeof (int) * sizeof (int); i < length; i++)
1051 ((char *) t)[i] = 0;
1053 TREE_SET_CODE (t, code);
1054 if (obstack == &permanent_obstack)
1055 TREE_PERMANENT (t) = 1;
1060 TREE_SIDE_EFFECTS (t) = 1;
1061 TREE_TYPE (t) = void_type_node;
1065 if (code != FUNCTION_DECL)
1067 DECL_IN_SYSTEM_HEADER (t)
1068 = in_system_header && (obstack == &permanent_obstack);
1069 DECL_SOURCE_LINE (t) = lineno;
1070 DECL_SOURCE_FILE (t) = (input_filename) ? input_filename : "<built-in>";
1071 DECL_UID (t) = next_decl_uid++;
1075 TYPE_UID (t) = next_type_uid++;
1077 TYPE_MAIN_VARIANT (t) = t;
1078 TYPE_OBSTACK (t) = obstack;
1079 TYPE_ATTRIBUTES (t) = NULL_TREE;
1080 #ifdef SET_DEFAULT_TYPE_ATTRIBUTES
1081 SET_DEFAULT_TYPE_ATTRIBUTES (t);
1086 TREE_CONSTANT (t) = 1;
1093 /* Return a new node with the same contents as NODE
1094 except that its TREE_CHAIN is zero and it has a fresh uid. */
1101 register enum tree_code code = TREE_CODE (node);
1102 register int length;
1105 switch (TREE_CODE_CLASS (code))
1107 case 'd': /* A decl node */
1108 length = sizeof (struct tree_decl);
1111 case 't': /* a type node */
1112 length = sizeof (struct tree_type);
1115 case 'b': /* a lexical block node */
1116 length = sizeof (struct tree_block);
1119 case 'r': /* a reference */
1120 case 'e': /* an expression */
1121 case 's': /* an expression with side effects */
1122 case '<': /* a comparison expression */
1123 case '1': /* a unary arithmetic expression */
1124 case '2': /* a binary arithmetic expression */
1125 length = sizeof (struct tree_exp)
1126 + (tree_code_length[(int) code] - 1) * sizeof (char *);
1129 case 'c': /* a constant */
1130 /* We can't use tree_code_length for INTEGER_CST, since the number of
1131 words is machine-dependent due to varying length of HOST_WIDE_INT,
1132 which might be wider than a pointer (e.g., long long). Similarly
1133 for REAL_CST, since the number of words is machine-dependent due
1134 to varying size and alignment of `double'. */
1135 if (code == INTEGER_CST)
1136 length = sizeof (struct tree_int_cst);
1137 else if (code == REAL_CST)
1138 length = sizeof (struct tree_real_cst);
1140 length = (sizeof (struct tree_common)
1141 + tree_code_length[(int) code] * sizeof (char *));
1144 case 'x': /* something random, like an identifier. */
1145 length = sizeof (struct tree_common)
1146 + tree_code_length[(int) code] * sizeof (char *);
1147 if (code == TREE_VEC)
1148 length += (TREE_VEC_LENGTH (node) - 1) * sizeof (char *);
1151 t = (tree) obstack_alloc (current_obstack, length);
1153 for (i = (length / sizeof (int)) - 1; i >= 0; i--)
1154 ((int *) t)[i] = ((int *) node)[i];
1155 /* Clear any extra bytes. */
1156 for (i = length / sizeof (int) * sizeof (int); i < length; i++)
1157 ((char *) t)[i] = ((char *) node)[i];
1160 TREE_ASM_WRITTEN (t) = 0;
1162 if (TREE_CODE_CLASS (code) == 'd')
1163 DECL_UID (t) = next_decl_uid++;
1164 else if (TREE_CODE_CLASS (code) == 't')
1166 TYPE_UID (t) = next_type_uid++;
1167 TYPE_OBSTACK (t) = current_obstack;
1169 /* The following is so that the debug code for
1170 the copy is different from the original type.
1171 The two statements usually duplicate each other
1172 (because they clear fields of the same union),
1173 but the optimizer should catch that. */
1174 TYPE_SYMTAB_POINTER (t) = 0;
1175 TYPE_SYMTAB_ADDRESS (t) = 0;
1178 TREE_PERMANENT (t) = (current_obstack == &permanent_obstack);
1183 /* Return a copy of a chain of nodes, chained through the TREE_CHAIN field.
1184 For example, this can copy a list made of TREE_LIST nodes. */
1191 register tree prev, next;
1196 head = prev = copy_node (list);
1197 next = TREE_CHAIN (list);
1200 TREE_CHAIN (prev) = copy_node (next);
1201 prev = TREE_CHAIN (prev);
1202 next = TREE_CHAIN (next);
1209 /* Return an IDENTIFIER_NODE whose name is TEXT (a null-terminated string).
1210 If an identifier with that name has previously been referred to,
1211 the same node is returned this time. */
1214 get_identifier (text)
1215 register char *text;
1220 register int len, hash_len;
1222 /* Compute length of text in len. */
1223 for (len = 0; text[len]; len++);
1225 /* Decide how much of that length to hash on */
1227 if (warn_id_clash && len > id_clash_len)
1228 hash_len = id_clash_len;
1230 /* Compute hash code */
1231 hi = hash_len * 613 + (unsigned) text[0];
1232 for (i = 1; i < hash_len; i += 2)
1233 hi = ((hi * 613) + (unsigned) (text[i]));
1235 hi &= (1 << HASHBITS) - 1;
1236 hi %= MAX_HASH_TABLE;
1238 /* Search table for identifier */
1239 for (idp = hash_table[hi]; idp; idp = TREE_CHAIN (idp))
1240 if (IDENTIFIER_LENGTH (idp) == len
1241 && IDENTIFIER_POINTER (idp)[0] == text[0]
1242 && !bcmp (IDENTIFIER_POINTER (idp), text, len))
1243 return idp; /* <-- return if found */
1245 /* Not found; optionally warn about a similar identifier */
1246 if (warn_id_clash && do_identifier_warnings && len >= id_clash_len)
1247 for (idp = hash_table[hi]; idp; idp = TREE_CHAIN (idp))
1248 if (!strncmp (IDENTIFIER_POINTER (idp), text, id_clash_len))
1250 warning ("`%s' and `%s' identical in first %d characters",
1251 IDENTIFIER_POINTER (idp), text, id_clash_len);
1255 if (tree_code_length[(int) IDENTIFIER_NODE] < 0)
1256 abort (); /* set_identifier_size hasn't been called. */
1258 /* Not found, create one, add to chain */
1259 idp = make_node (IDENTIFIER_NODE);
1260 IDENTIFIER_LENGTH (idp) = len;
1261 #ifdef GATHER_STATISTICS
1262 id_string_size += len;
1265 IDENTIFIER_POINTER (idp) = obstack_copy0 (&permanent_obstack, text, len);
1267 TREE_CHAIN (idp) = hash_table[hi];
1268 hash_table[hi] = idp;
1269 return idp; /* <-- return if created */
1272 /* If an identifier with the name TEXT (a null-terminated string) has
1273 previously been referred to, return that node; otherwise return
1277 maybe_get_identifier (text)
1278 register char *text;
1283 register int len, hash_len;
1285 /* Compute length of text in len. */
1286 for (len = 0; text[len]; len++);
1288 /* Decide how much of that length to hash on */
1290 if (warn_id_clash && len > id_clash_len)
1291 hash_len = id_clash_len;
1293 /* Compute hash code */
1294 hi = hash_len * 613 + (unsigned) text[0];
1295 for (i = 1; i < hash_len; i += 2)
1296 hi = ((hi * 613) + (unsigned) (text[i]));
1298 hi &= (1 << HASHBITS) - 1;
1299 hi %= MAX_HASH_TABLE;
1301 /* Search table for identifier */
1302 for (idp = hash_table[hi]; idp; idp = TREE_CHAIN (idp))
1303 if (IDENTIFIER_LENGTH (idp) == len
1304 && IDENTIFIER_POINTER (idp)[0] == text[0]
1305 && !bcmp (IDENTIFIER_POINTER (idp), text, len))
1306 return idp; /* <-- return if found */
1311 /* Enable warnings on similar identifiers (if requested).
1312 Done after the built-in identifiers are created. */
1315 start_identifier_warnings ()
1317 do_identifier_warnings = 1;
1320 /* Record the size of an identifier node for the language in use.
1321 SIZE is the total size in bytes.
1322 This is called by the language-specific files. This must be
1323 called before allocating any identifiers. */
1326 set_identifier_size (size)
1329 tree_code_length[(int) IDENTIFIER_NODE]
1330 = (size - sizeof (struct tree_common)) / sizeof (tree);
1333 /* Return a newly constructed INTEGER_CST node whose constant value
1334 is specified by the two ints LOW and HI.
1335 The TREE_TYPE is set to `int'.
1337 This function should be used via the `build_int_2' macro. */
1340 build_int_2_wide (low, hi)
1341 HOST_WIDE_INT low, hi;
1343 register tree t = make_node (INTEGER_CST);
1344 TREE_INT_CST_LOW (t) = low;
1345 TREE_INT_CST_HIGH (t) = hi;
1346 TREE_TYPE (t) = integer_type_node;
1350 /* Return a new REAL_CST node whose type is TYPE and value is D. */
1353 build_real (type, d)
1360 /* Check for valid float value for this type on this target machine;
1361 if not, can print error message and store a valid value in D. */
1362 #ifdef CHECK_FLOAT_VALUE
1363 CHECK_FLOAT_VALUE (TYPE_MODE (type), d, overflow);
1366 v = make_node (REAL_CST);
1367 TREE_TYPE (v) = type;
1368 TREE_REAL_CST (v) = d;
1369 TREE_OVERFLOW (v) = TREE_CONSTANT_OVERFLOW (v) = overflow;
1373 /* Return a new REAL_CST node whose type is TYPE
1374 and whose value is the integer value of the INTEGER_CST node I. */
1376 #if !defined (REAL_IS_NOT_DOUBLE) || defined (REAL_ARITHMETIC)
1379 real_value_from_int_cst (type, i)
1384 /* Some 386 compilers mishandle unsigned int to float conversions,
1385 so introduce a temporary variable E to avoid those bugs. */
1387 #ifdef REAL_ARITHMETIC
1388 if (! TREE_UNSIGNED (TREE_TYPE (i)))
1389 REAL_VALUE_FROM_INT (d, TREE_INT_CST_LOW (i), TREE_INT_CST_HIGH (i),
1392 REAL_VALUE_FROM_UNSIGNED_INT (d, TREE_INT_CST_LOW (i),
1393 TREE_INT_CST_HIGH (i), TYPE_MODE (type));
1394 #else /* not REAL_ARITHMETIC */
1395 if (TREE_INT_CST_HIGH (i) < 0 && ! TREE_UNSIGNED (TREE_TYPE (i)))
1397 d = (double) (~ TREE_INT_CST_HIGH (i));
1398 e = ((double) ((HOST_WIDE_INT) 1 << (HOST_BITS_PER_WIDE_INT / 2))
1399 * (double) ((HOST_WIDE_INT) 1 << (HOST_BITS_PER_WIDE_INT / 2)));
1401 e = (double) (unsigned HOST_WIDE_INT) (~ TREE_INT_CST_LOW (i));
1407 d = (double) (unsigned HOST_WIDE_INT) TREE_INT_CST_HIGH (i);
1408 e = ((double) ((HOST_WIDE_INT) 1 << (HOST_BITS_PER_WIDE_INT / 2))
1409 * (double) ((HOST_WIDE_INT) 1 << (HOST_BITS_PER_WIDE_INT / 2)));
1411 e = (double) (unsigned HOST_WIDE_INT) TREE_INT_CST_LOW (i);
1414 #endif /* not REAL_ARITHMETIC */
1418 /* This function can't be implemented if we can't do arithmetic
1419 on the float representation. */
1422 build_real_from_int_cst (type, i)
1427 int overflow = TREE_OVERFLOW (i);
1429 jmp_buf float_error;
1431 v = make_node (REAL_CST);
1432 TREE_TYPE (v) = type;
1434 if (setjmp (float_error))
1441 set_float_handler (float_error);
1443 #ifdef REAL_ARITHMETIC
1444 d = real_value_from_int_cst (type, i);
1446 d = REAL_VALUE_TRUNCATE (TYPE_MODE (type),
1447 real_value_from_int_cst (type, i));
1450 /* Check for valid float value for this type on this target machine. */
1453 set_float_handler (NULL_PTR);
1455 #ifdef CHECK_FLOAT_VALUE
1456 CHECK_FLOAT_VALUE (TYPE_MODE (type), d, overflow);
1459 TREE_REAL_CST (v) = d;
1460 TREE_OVERFLOW (v) = TREE_CONSTANT_OVERFLOW (v) = overflow;
1464 #endif /* not REAL_IS_NOT_DOUBLE, or REAL_ARITHMETIC */
1466 /* Return a newly constructed STRING_CST node whose value is
1467 the LEN characters at STR.
1468 The TREE_TYPE is not initialized. */
1471 build_string (len, str)
1475 /* Put the string in saveable_obstack since it will be placed in the RTL
1476 for an "asm" statement and will also be kept around a while if
1477 deferring constant output in varasm.c. */
1479 register tree s = make_node (STRING_CST);
1480 TREE_STRING_LENGTH (s) = len;
1481 TREE_STRING_POINTER (s) = obstack_copy0 (saveable_obstack, str, len);
1485 /* Return a newly constructed COMPLEX_CST node whose value is
1486 specified by the real and imaginary parts REAL and IMAG.
1487 Both REAL and IMAG should be constant nodes. TYPE, if specified,
1488 will be the type of the COMPLEX_CST; otherwise a new type will be made. */
1491 build_complex (type, real, imag)
1495 register tree t = make_node (COMPLEX_CST);
1497 TREE_REALPART (t) = real;
1498 TREE_IMAGPART (t) = imag;
1499 TREE_TYPE (t) = type ? type : build_complex_type (TREE_TYPE (real));
1500 TREE_OVERFLOW (t) = TREE_OVERFLOW (real) | TREE_OVERFLOW (imag);
1501 TREE_CONSTANT_OVERFLOW (t)
1502 = TREE_CONSTANT_OVERFLOW (real) | TREE_CONSTANT_OVERFLOW (imag);
1506 /* Build a newly constructed TREE_VEC node of length LEN. */
1513 register int length = (len-1) * sizeof (tree) + sizeof (struct tree_vec);
1514 register struct obstack *obstack = current_obstack;
1517 #ifdef GATHER_STATISTICS
1518 tree_node_counts[(int)vec_kind]++;
1519 tree_node_sizes[(int)vec_kind] += length;
1522 t = (tree) obstack_alloc (obstack, length);
1524 for (i = (length / sizeof (int)) - 1; i >= 0; i--)
1527 TREE_SET_CODE (t, TREE_VEC);
1528 TREE_VEC_LENGTH (t) = len;
1529 if (obstack == &permanent_obstack)
1530 TREE_PERMANENT (t) = 1;
1535 /* Return 1 if EXPR is the integer constant zero or a complex constant
1539 integer_zerop (expr)
1544 return ((TREE_CODE (expr) == INTEGER_CST
1545 && ! TREE_CONSTANT_OVERFLOW (expr)
1546 && TREE_INT_CST_LOW (expr) == 0
1547 && TREE_INT_CST_HIGH (expr) == 0)
1548 || (TREE_CODE (expr) == COMPLEX_CST
1549 && integer_zerop (TREE_REALPART (expr))
1550 && integer_zerop (TREE_IMAGPART (expr))));
1553 /* Return 1 if EXPR is the integer constant one or the corresponding
1554 complex constant. */
1562 return ((TREE_CODE (expr) == INTEGER_CST
1563 && ! TREE_CONSTANT_OVERFLOW (expr)
1564 && TREE_INT_CST_LOW (expr) == 1
1565 && TREE_INT_CST_HIGH (expr) == 0)
1566 || (TREE_CODE (expr) == COMPLEX_CST
1567 && integer_onep (TREE_REALPART (expr))
1568 && integer_zerop (TREE_IMAGPART (expr))));
1571 /* Return 1 if EXPR is an integer containing all 1's in as much precision as
1572 it contains. Likewise for the corresponding complex constant. */
1575 integer_all_onesp (expr)
1583 if (TREE_CODE (expr) == COMPLEX_CST
1584 && integer_all_onesp (TREE_REALPART (expr))
1585 && integer_zerop (TREE_IMAGPART (expr)))
1588 else if (TREE_CODE (expr) != INTEGER_CST
1589 || TREE_CONSTANT_OVERFLOW (expr))
1592 uns = TREE_UNSIGNED (TREE_TYPE (expr));
1594 return TREE_INT_CST_LOW (expr) == -1 && TREE_INT_CST_HIGH (expr) == -1;
1596 /* Note that using TYPE_PRECISION here is wrong. We care about the
1597 actual bits, not the (arbitrary) range of the type. */
1598 prec = GET_MODE_BITSIZE (TYPE_MODE (TREE_TYPE (expr)));
1599 if (prec >= HOST_BITS_PER_WIDE_INT)
1601 int high_value, shift_amount;
1603 shift_amount = prec - HOST_BITS_PER_WIDE_INT;
1605 if (shift_amount > HOST_BITS_PER_WIDE_INT)
1606 /* Can not handle precisions greater than twice the host int size. */
1608 else if (shift_amount == HOST_BITS_PER_WIDE_INT)
1609 /* Shifting by the host word size is undefined according to the ANSI
1610 standard, so we must handle this as a special case. */
1613 high_value = ((HOST_WIDE_INT) 1 << shift_amount) - 1;
1615 return TREE_INT_CST_LOW (expr) == -1
1616 && TREE_INT_CST_HIGH (expr) == high_value;
1619 return TREE_INT_CST_LOW (expr) == ((HOST_WIDE_INT) 1 << prec) - 1;
1622 /* Return 1 if EXPR is an integer constant that is a power of 2 (i.e., has only
1626 integer_pow2p (expr)
1630 HOST_WIDE_INT high, low;
1634 if (TREE_CODE (expr) == COMPLEX_CST
1635 && integer_pow2p (TREE_REALPART (expr))
1636 && integer_zerop (TREE_IMAGPART (expr)))
1639 if (TREE_CODE (expr) != INTEGER_CST || TREE_CONSTANT_OVERFLOW (expr))
1642 prec = (TREE_CODE (TREE_TYPE (expr)) == POINTER_TYPE
1643 ? POINTER_SIZE : TYPE_PRECISION (TREE_TYPE (expr)));
1644 high = TREE_INT_CST_HIGH (expr);
1645 low = TREE_INT_CST_LOW (expr);
1647 /* First clear all bits that are beyond the type's precision in case
1648 we've been sign extended. */
1650 if (prec == 2 * HOST_BITS_PER_WIDE_INT)
1652 else if (prec > HOST_BITS_PER_WIDE_INT)
1653 high &= ~((HOST_WIDE_INT) (-1) << (prec - HOST_BITS_PER_WIDE_INT));
1657 if (prec < HOST_BITS_PER_WIDE_INT)
1658 low &= ~((HOST_WIDE_INT) (-1) << prec);
1661 if (high == 0 && low == 0)
1664 return ((high == 0 && (low & (low - 1)) == 0)
1665 || (low == 0 && (high & (high - 1)) == 0));
1668 /* Return the power of two represented by a tree node known to be a
1676 HOST_WIDE_INT high, low;
1680 if (TREE_CODE (expr) == COMPLEX_CST)
1681 return tree_log2 (TREE_REALPART (expr));
1683 prec = (TREE_CODE (TREE_TYPE (expr)) == POINTER_TYPE
1684 ? POINTER_SIZE : TYPE_PRECISION (TREE_TYPE (expr)));
1686 high = TREE_INT_CST_HIGH (expr);
1687 low = TREE_INT_CST_LOW (expr);
1689 /* First clear all bits that are beyond the type's precision in case
1690 we've been sign extended. */
1692 if (prec == 2 * HOST_BITS_PER_WIDE_INT)
1694 else if (prec > HOST_BITS_PER_WIDE_INT)
1695 high &= ~((HOST_WIDE_INT) (-1) << (prec - HOST_BITS_PER_WIDE_INT));
1699 if (prec < HOST_BITS_PER_WIDE_INT)
1700 low &= ~((HOST_WIDE_INT) (-1) << prec);
1703 return (high != 0 ? HOST_BITS_PER_WIDE_INT + exact_log2 (high)
1704 : exact_log2 (low));
1707 /* Return 1 if EXPR is the real constant zero. */
1715 return ((TREE_CODE (expr) == REAL_CST
1716 && ! TREE_CONSTANT_OVERFLOW (expr)
1717 && REAL_VALUES_EQUAL (TREE_REAL_CST (expr), dconst0))
1718 || (TREE_CODE (expr) == COMPLEX_CST
1719 && real_zerop (TREE_REALPART (expr))
1720 && real_zerop (TREE_IMAGPART (expr))));
1723 /* Return 1 if EXPR is the real constant one in real or complex form. */
1731 return ((TREE_CODE (expr) == REAL_CST
1732 && ! TREE_CONSTANT_OVERFLOW (expr)
1733 && REAL_VALUES_EQUAL (TREE_REAL_CST (expr), dconst1))
1734 || (TREE_CODE (expr) == COMPLEX_CST
1735 && real_onep (TREE_REALPART (expr))
1736 && real_zerop (TREE_IMAGPART (expr))));
1739 /* Return 1 if EXPR is the real constant two. */
1747 return ((TREE_CODE (expr) == REAL_CST
1748 && ! TREE_CONSTANT_OVERFLOW (expr)
1749 && REAL_VALUES_EQUAL (TREE_REAL_CST (expr), dconst2))
1750 || (TREE_CODE (expr) == COMPLEX_CST
1751 && real_twop (TREE_REALPART (expr))
1752 && real_zerop (TREE_IMAGPART (expr))));
1755 /* Nonzero if EXP is a constant or a cast of a constant. */
1758 really_constant_p (exp)
1761 /* This is not quite the same as STRIP_NOPS. It does more. */
1762 while (TREE_CODE (exp) == NOP_EXPR
1763 || TREE_CODE (exp) == CONVERT_EXPR
1764 || TREE_CODE (exp) == NON_LVALUE_EXPR)
1765 exp = TREE_OPERAND (exp, 0);
1766 return TREE_CONSTANT (exp);
1769 /* Return first list element whose TREE_VALUE is ELEM.
1770 Return 0 if ELEM is not in LIST. */
1773 value_member (elem, list)
1778 if (elem == TREE_VALUE (list))
1780 list = TREE_CHAIN (list);
1785 /* Return first list element whose TREE_PURPOSE is ELEM.
1786 Return 0 if ELEM is not in LIST. */
1789 purpose_member (elem, list)
1794 if (elem == TREE_PURPOSE (list))
1796 list = TREE_CHAIN (list);
1801 /* Return first list element whose BINFO_TYPE is ELEM.
1802 Return 0 if ELEM is not in LIST. */
1805 binfo_member (elem, list)
1810 if (elem == BINFO_TYPE (list))
1812 list = TREE_CHAIN (list);
1817 /* Return nonzero if ELEM is part of the chain CHAIN. */
1820 chain_member (elem, chain)
1827 chain = TREE_CHAIN (chain);
1833 /* Return nonzero if ELEM is equal to TREE_VALUE (CHAIN) for any piece of
1835 /* ??? This function was added for machine specific attributes but is no
1836 longer used. It could be deleted if we could confirm all front ends
1840 chain_member_value (elem, chain)
1845 if (elem == TREE_VALUE (chain))
1847 chain = TREE_CHAIN (chain);
1853 /* Return nonzero if ELEM is equal to TREE_PURPOSE (CHAIN)
1854 for any piece of chain CHAIN. */
1855 /* ??? This function was added for machine specific attributes but is no
1856 longer used. It could be deleted if we could confirm all front ends
1860 chain_member_purpose (elem, chain)
1865 if (elem == TREE_PURPOSE (chain))
1867 chain = TREE_CHAIN (chain);
1873 /* Return the length of a chain of nodes chained through TREE_CHAIN.
1874 We expect a null pointer to mark the end of the chain.
1875 This is the Lisp primitive `length'. */
1882 register int len = 0;
1884 for (tail = t; tail; tail = TREE_CHAIN (tail))
1890 /* Concatenate two chains of nodes (chained through TREE_CHAIN)
1891 by modifying the last node in chain 1 to point to chain 2.
1892 This is the Lisp primitive `nconc'. */
1904 for (t1 = op1; TREE_CHAIN (t1); t1 = TREE_CHAIN (t1))
1906 TREE_CHAIN (t1) = op2;
1907 for (t2 = op2; t2; t2 = TREE_CHAIN (t2))
1909 abort (); /* Circularity created. */
1915 /* Return the last node in a chain of nodes (chained through TREE_CHAIN). */
1919 register tree chain;
1923 while (next = TREE_CHAIN (chain))
1928 /* Reverse the order of elements in the chain T,
1929 and return the new head of the chain (old last element). */
1935 register tree prev = 0, decl, next;
1936 for (decl = t; decl; decl = next)
1938 next = TREE_CHAIN (decl);
1939 TREE_CHAIN (decl) = prev;
1945 /* Given a chain CHAIN of tree nodes,
1946 construct and return a list of those nodes. */
1952 tree result = NULL_TREE;
1953 tree in_tail = chain;
1954 tree out_tail = NULL_TREE;
1958 tree next = tree_cons (NULL_TREE, in_tail, NULL_TREE);
1960 TREE_CHAIN (out_tail) = next;
1964 in_tail = TREE_CHAIN (in_tail);
1970 /* Return a newly created TREE_LIST node whose
1971 purpose and value fields are PARM and VALUE. */
1974 build_tree_list (parm, value)
1977 register tree t = make_node (TREE_LIST);
1978 TREE_PURPOSE (t) = parm;
1979 TREE_VALUE (t) = value;
1983 /* Similar, but build on the temp_decl_obstack. */
1986 build_decl_list (parm, value)
1990 register struct obstack *ambient_obstack = current_obstack;
1991 current_obstack = &temp_decl_obstack;
1992 node = build_tree_list (parm, value);
1993 current_obstack = ambient_obstack;
1997 /* Return a newly created TREE_LIST node whose
1998 purpose and value fields are PARM and VALUE
1999 and whose TREE_CHAIN is CHAIN. */
2002 tree_cons (purpose, value, chain)
2003 tree purpose, value, chain;
2006 register tree node = make_node (TREE_LIST);
2009 register tree node = (tree) obstack_alloc (current_obstack, sizeof (struct tree_list));
2010 #ifdef GATHER_STATISTICS
2011 tree_node_counts[(int)x_kind]++;
2012 tree_node_sizes[(int)x_kind] += sizeof (struct tree_list);
2015 for (i = (sizeof (struct tree_common) / sizeof (int)) - 1; i >= 0; i--)
2016 ((int *) node)[i] = 0;
2018 TREE_SET_CODE (node, TREE_LIST);
2019 if (current_obstack == &permanent_obstack)
2020 TREE_PERMANENT (node) = 1;
2023 TREE_CHAIN (node) = chain;
2024 TREE_PURPOSE (node) = purpose;
2025 TREE_VALUE (node) = value;
2029 /* Similar, but build on the temp_decl_obstack. */
2032 decl_tree_cons (purpose, value, chain)
2033 tree purpose, value, chain;
2036 register struct obstack *ambient_obstack = current_obstack;
2037 current_obstack = &temp_decl_obstack;
2038 node = tree_cons (purpose, value, chain);
2039 current_obstack = ambient_obstack;
2043 /* Same as `tree_cons' but make a permanent object. */
2046 perm_tree_cons (purpose, value, chain)
2047 tree purpose, value, chain;
2050 register struct obstack *ambient_obstack = current_obstack;
2051 current_obstack = &permanent_obstack;
2053 node = tree_cons (purpose, value, chain);
2054 current_obstack = ambient_obstack;
2058 /* Same as `tree_cons', but make this node temporary, regardless. */
2061 temp_tree_cons (purpose, value, chain)
2062 tree purpose, value, chain;
2065 register struct obstack *ambient_obstack = current_obstack;
2066 current_obstack = &temporary_obstack;
2068 node = tree_cons (purpose, value, chain);
2069 current_obstack = ambient_obstack;
2073 /* Same as `tree_cons', but save this node if the function's RTL is saved. */
2076 saveable_tree_cons (purpose, value, chain)
2077 tree purpose, value, chain;
2080 register struct obstack *ambient_obstack = current_obstack;
2081 current_obstack = saveable_obstack;
2083 node = tree_cons (purpose, value, chain);
2084 current_obstack = ambient_obstack;
2088 /* Return the size nominally occupied by an object of type TYPE
2089 when it resides in memory. The value is measured in units of bytes,
2090 and its data type is that normally used for type sizes
2091 (which is the first type created by make_signed_type or
2092 make_unsigned_type). */
2095 size_in_bytes (type)
2100 if (type == error_mark_node)
2101 return integer_zero_node;
2102 type = TYPE_MAIN_VARIANT (type);
2103 if (TYPE_SIZE (type) == 0)
2105 incomplete_type_error (NULL_TREE, type);
2106 return integer_zero_node;
2108 t = size_binop (CEIL_DIV_EXPR, TYPE_SIZE (type),
2109 size_int (BITS_PER_UNIT));
2110 if (TREE_CODE (t) == INTEGER_CST)
2111 force_fit_type (t, 0);
2115 /* Return the size of TYPE (in bytes) as an integer,
2116 or return -1 if the size can vary. */
2119 int_size_in_bytes (type)
2123 if (type == error_mark_node)
2125 type = TYPE_MAIN_VARIANT (type);
2126 if (TYPE_SIZE (type) == 0)
2128 if (TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
2130 if (TREE_INT_CST_HIGH (TYPE_SIZE (type)) != 0)
2132 tree t = size_binop (CEIL_DIV_EXPR, TYPE_SIZE (type),
2133 size_int (BITS_PER_UNIT));
2134 return TREE_INT_CST_LOW (t);
2136 size = TREE_INT_CST_LOW (TYPE_SIZE (type));
2137 return (size + BITS_PER_UNIT - 1) / BITS_PER_UNIT;
2140 /* Return, as a tree node, the number of elements for TYPE (which is an
2141 ARRAY_TYPE) minus one. This counts only elements of the top array.
2143 Don't let any SAVE_EXPRs escape; if we are called as part of a cleanup
2144 action, they would get unsaved. */
2147 array_type_nelts (type)
2150 tree index_type, min, max;
2152 /* If they did it with unspecified bounds, then we should have already
2153 given an error about it before we got here. */
2154 if (! TYPE_DOMAIN (type))
2155 return error_mark_node;
2157 index_type = TYPE_DOMAIN (type);
2158 min = TYPE_MIN_VALUE (index_type);
2159 max = TYPE_MAX_VALUE (index_type);
2161 if (! TREE_CONSTANT (min))
2164 if (TREE_CODE (min) == SAVE_EXPR)
2165 min = build (RTL_EXPR, TREE_TYPE (TYPE_MIN_VALUE (index_type)), 0,
2166 SAVE_EXPR_RTL (min));
2168 min = TYPE_MIN_VALUE (index_type);
2171 if (! TREE_CONSTANT (max))
2174 if (TREE_CODE (max) == SAVE_EXPR)
2175 max = build (RTL_EXPR, TREE_TYPE (TYPE_MAX_VALUE (index_type)), 0,
2176 SAVE_EXPR_RTL (max));
2178 max = TYPE_MAX_VALUE (index_type);
2181 return (integer_zerop (min)
2183 : fold (build (MINUS_EXPR, TREE_TYPE (max), max, min)));
2186 /* Return nonzero if arg is static -- a reference to an object in
2187 static storage. This is not the same as the C meaning of `static'. */
2193 switch (TREE_CODE (arg))
2196 /* Nested functions aren't static, since taking their address
2197 involves a trampoline. */
2198 return decl_function_context (arg) == 0 || DECL_NO_STATIC_CHAIN (arg);
2200 return TREE_STATIC (arg) || DECL_EXTERNAL (arg);
2203 return TREE_STATIC (arg);
2208 /* If we are referencing a bitfield, we can't evaluate an
2209 ADDR_EXPR at compile time and so it isn't a constant. */
2211 return (! DECL_BIT_FIELD (TREE_OPERAND (arg, 1))
2212 && staticp (TREE_OPERAND (arg, 0)));
2218 /* This case is technically correct, but results in setting
2219 TREE_CONSTANT on ADDR_EXPRs that cannot be evaluated at
2222 return TREE_CONSTANT (TREE_OPERAND (arg, 0));
2226 if (TREE_CODE (TYPE_SIZE (TREE_TYPE (arg))) == INTEGER_CST
2227 && TREE_CODE (TREE_OPERAND (arg, 1)) == INTEGER_CST)
2228 return staticp (TREE_OPERAND (arg, 0));
2234 /* Wrap a SAVE_EXPR around EXPR, if appropriate.
2235 Do this to any expression which may be used in more than one place,
2236 but must be evaluated only once.
2238 Normally, expand_expr would reevaluate the expression each time.
2239 Calling save_expr produces something that is evaluated and recorded
2240 the first time expand_expr is called on it. Subsequent calls to
2241 expand_expr just reuse the recorded value.
2243 The call to expand_expr that generates code that actually computes
2244 the value is the first call *at compile time*. Subsequent calls
2245 *at compile time* generate code to use the saved value.
2246 This produces correct result provided that *at run time* control
2247 always flows through the insns made by the first expand_expr
2248 before reaching the other places where the save_expr was evaluated.
2249 You, the caller of save_expr, must make sure this is so.
2251 Constants, and certain read-only nodes, are returned with no
2252 SAVE_EXPR because that is safe. Expressions containing placeholders
2253 are not touched; see tree.def for an explanation of what these
2260 register tree t = fold (expr);
2262 /* We don't care about whether this can be used as an lvalue in this
2264 while (TREE_CODE (t) == NON_LVALUE_EXPR)
2265 t = TREE_OPERAND (t, 0);
2267 /* If the tree evaluates to a constant, then we don't want to hide that
2268 fact (i.e. this allows further folding, and direct checks for constants).
2269 However, a read-only object that has side effects cannot be bypassed.
2270 Since it is no problem to reevaluate literals, we just return the
2273 if (TREE_CONSTANT (t) || (TREE_READONLY (t) && ! TREE_SIDE_EFFECTS (t))
2274 || TREE_CODE (t) == SAVE_EXPR || TREE_CODE (t) == ERROR_MARK)
2277 /* If T contains a PLACEHOLDER_EXPR, we must evaluate it each time, since
2278 it means that the size or offset of some field of an object depends on
2279 the value within another field.
2281 Note that it must not be the case that T contains both a PLACEHOLDER_EXPR
2282 and some variable since it would then need to be both evaluated once and
2283 evaluated more than once. Front-ends must assure this case cannot
2284 happen by surrounding any such subexpressions in their own SAVE_EXPR
2285 and forcing evaluation at the proper time. */
2286 if (contains_placeholder_p (t))
2289 t = build (SAVE_EXPR, TREE_TYPE (expr), t, current_function_decl, NULL_TREE);
2291 /* This expression might be placed ahead of a jump to ensure that the
2292 value was computed on both sides of the jump. So make sure it isn't
2293 eliminated as dead. */
2294 TREE_SIDE_EFFECTS (t) = 1;
2298 /* Arrange for an expression to be expanded multiple independent
2299 times. This is useful for cleanup actions, as the backend can
2300 expand them multiple times in different places. */
2308 /* If this is already protected, no sense in protecting it again. */
2309 if (TREE_CODE (expr) == UNSAVE_EXPR)
2312 t = build1 (UNSAVE_EXPR, TREE_TYPE (expr), expr);
2313 TREE_SIDE_EFFECTS (t) = TREE_SIDE_EFFECTS (expr);
2317 /* Modify a tree in place so that all the evaluate only once things
2318 are cleared out. Return the EXPR given. */
2321 unsave_expr_now (expr)
2324 enum tree_code code;
2328 if (expr == NULL_TREE)
2331 code = TREE_CODE (expr);
2332 first_rtl = tree_code_length [(int) code];
2336 SAVE_EXPR_RTL (expr) = 0;
2341 TREE_OPERAND (expr, 1) = TREE_OPERAND (expr, 3);
2342 TREE_OPERAND (expr, 3) = NULL_TREE;
2346 /* I don't yet know how to emit a sequence multiple times. */
2347 if (RTL_EXPR_SEQUENCE (expr) != 0)
2353 CALL_EXPR_RTL (expr) = 0;
2354 if (TREE_OPERAND (expr, 1)
2355 && TREE_CODE (TREE_OPERAND (expr, 1)) == TREE_LIST)
2357 tree exp = TREE_OPERAND (expr, 1);
2360 unsave_expr_now (TREE_VALUE (exp));
2361 exp = TREE_CHAIN (exp);
2367 case WITH_CLEANUP_EXPR:
2368 /* Should be defined to be 2. */
2372 case METHOD_CALL_EXPR:
2377 switch (TREE_CODE_CLASS (code))
2379 case 'c': /* a constant */
2380 case 't': /* a type node */
2381 case 'x': /* something random, like an identifier or an ERROR_MARK. */
2382 case 'd': /* A decl node */
2383 case 'b': /* A block node */
2386 case 'e': /* an expression */
2387 case 'r': /* a reference */
2388 case 's': /* an expression with side effects */
2389 case '<': /* a comparison expression */
2390 case '2': /* a binary arithmetic expression */
2391 case '1': /* a unary arithmetic expression */
2392 for (i = first_rtl - 1; i >= 0; i--)
2393 unsave_expr_now (TREE_OPERAND (expr, i));
2401 /* Return 1 if EXP contains a PLACEHOLDER_EXPR; i.e., if it represents a size
2402 or offset that depends on a field within a record. */
2405 contains_placeholder_p (exp)
2408 register enum tree_code code = TREE_CODE (exp);
2410 /* If we have a WITH_RECORD_EXPR, it "cancels" any PLACEHOLDER_EXPR
2411 in it since it is supplying a value for it. */
2412 if (code == WITH_RECORD_EXPR)
2414 else if (code == PLACEHOLDER_EXPR)
2417 switch (TREE_CODE_CLASS (code))
2420 /* Don't look at any PLACEHOLDER_EXPRs that might be in index or bit
2421 position computations since they will be converted into a
2422 WITH_RECORD_EXPR involving the reference, which will assume
2423 here will be valid. */
2424 return contains_placeholder_p (TREE_OPERAND (exp, 0));
2432 /* Ignoring the first operand isn't quite right, but works best. */
2433 return contains_placeholder_p (TREE_OPERAND (exp, 1));
2440 return (contains_placeholder_p (TREE_OPERAND (exp, 0))
2441 || contains_placeholder_p (TREE_OPERAND (exp, 1))
2442 || contains_placeholder_p (TREE_OPERAND (exp, 2)));
2445 return (SAVE_EXPR_RTL (exp) == 0
2446 && contains_placeholder_p (TREE_OPERAND (exp, 0)));
2449 switch (tree_code_length[(int) code])
2452 return contains_placeholder_p (TREE_OPERAND (exp, 0));
2454 return (contains_placeholder_p (TREE_OPERAND (exp, 0))
2455 || contains_placeholder_p (TREE_OPERAND (exp, 1)));
2462 /* Given a tree EXP, a FIELD_DECL F, and a replacement value R,
2463 return a tree with all occurrences of references to F in a
2464 PLACEHOLDER_EXPR replaced by R. Note that we assume here that EXP
2465 contains only arithmetic expressions. */
2468 substitute_in_expr (exp, f, r)
2473 enum tree_code code = TREE_CODE (exp);
2478 switch (TREE_CODE_CLASS (code))
2485 if (code == PLACEHOLDER_EXPR)
2493 switch (tree_code_length[(int) code])
2496 op0 = substitute_in_expr (TREE_OPERAND (exp, 0), f, r);
2497 if (op0 == TREE_OPERAND (exp, 0))
2500 new = fold (build1 (code, TREE_TYPE (exp), op0));
2504 /* An RTL_EXPR cannot contain a PLACEHOLDER_EXPR; a CONSTRUCTOR
2505 could, but we don't support it. */
2506 if (code == RTL_EXPR)
2508 else if (code == CONSTRUCTOR)
2511 op0 = substitute_in_expr (TREE_OPERAND (exp, 0), f, r);
2512 op1 = substitute_in_expr (TREE_OPERAND (exp, 1), f, r);
2513 if (op0 == TREE_OPERAND (exp, 0) && op1 == TREE_OPERAND (exp, 1))
2516 new = fold (build (code, TREE_TYPE (exp), op0, op1));
2520 /* It cannot be that anything inside a SAVE_EXPR contains a
2521 PLACEHOLDER_EXPR. */
2522 if (code == SAVE_EXPR)
2525 if (code != COND_EXPR)
2528 op0 = substitute_in_expr (TREE_OPERAND (exp, 0), f, r);
2529 op1 = substitute_in_expr (TREE_OPERAND (exp, 1), f, r);
2530 op2 = substitute_in_expr (TREE_OPERAND (exp, 2), f, r);
2531 if (op0 == TREE_OPERAND (exp, 0) && op1 == TREE_OPERAND (exp, 1)
2532 && op2 == TREE_OPERAND (exp, 2))
2535 new = fold (build (code, TREE_TYPE (exp), op0, op1, op2));
2544 /* If this expression is getting a value from a PLACEHOLDER_EXPR
2545 and it is the right field, replace it with R. */
2546 for (inner = TREE_OPERAND (exp, 0);
2547 TREE_CODE_CLASS (TREE_CODE (inner)) == 'r';
2548 inner = TREE_OPERAND (inner, 0))
2550 if (TREE_CODE (inner) == PLACEHOLDER_EXPR
2551 && TREE_OPERAND (exp, 1) == f)
2554 /* If this expression hasn't been completed let, leave it
2556 if (TREE_CODE (inner) == PLACEHOLDER_EXPR
2557 && TREE_TYPE (inner) == 0)
2560 op0 = substitute_in_expr (TREE_OPERAND (exp, 0), f, r);
2561 if (op0 == TREE_OPERAND (exp, 0))
2564 new = fold (build (code, TREE_TYPE (exp), op0,
2565 TREE_OPERAND (exp, 1)));
2569 op0 = substitute_in_expr (TREE_OPERAND (exp, 0), f, r);
2570 op1 = substitute_in_expr (TREE_OPERAND (exp, 1), f, r);
2571 op2 = substitute_in_expr (TREE_OPERAND (exp, 2), f, r);
2572 if (op0 == TREE_OPERAND (exp, 0) && op1 == TREE_OPERAND (exp, 1)
2573 && op2 == TREE_OPERAND (exp, 2))
2576 new = fold (build (code, TREE_TYPE (exp), op0, op1, op2));
2581 op0 = substitute_in_expr (TREE_OPERAND (exp, 0), f, r);
2582 if (op0 == TREE_OPERAND (exp, 0))
2585 new = fold (build1 (code, TREE_TYPE (exp), op0));
2590 /* If it wasn't one of the cases we handle, give up. */
2594 TREE_READONLY (new) = TREE_READONLY (exp);
2598 /* Stabilize a reference so that we can use it any number of times
2599 without causing its operands to be evaluated more than once.
2600 Returns the stabilized reference. This works by means of save_expr,
2601 so see the caveats in the comments about save_expr.
2603 Also allows conversion expressions whose operands are references.
2604 Any other kind of expression is returned unchanged. */
2607 stabilize_reference (ref)
2610 register tree result;
2611 register enum tree_code code = TREE_CODE (ref);
2618 /* No action is needed in this case. */
2624 case FIX_TRUNC_EXPR:
2625 case FIX_FLOOR_EXPR:
2626 case FIX_ROUND_EXPR:
2628 result = build_nt (code, stabilize_reference (TREE_OPERAND (ref, 0)));
2632 result = build_nt (INDIRECT_REF,
2633 stabilize_reference_1 (TREE_OPERAND (ref, 0)));
2637 result = build_nt (COMPONENT_REF,
2638 stabilize_reference (TREE_OPERAND (ref, 0)),
2639 TREE_OPERAND (ref, 1));
2643 result = build_nt (BIT_FIELD_REF,
2644 stabilize_reference (TREE_OPERAND (ref, 0)),
2645 stabilize_reference_1 (TREE_OPERAND (ref, 1)),
2646 stabilize_reference_1 (TREE_OPERAND (ref, 2)));
2650 result = build_nt (ARRAY_REF,
2651 stabilize_reference (TREE_OPERAND (ref, 0)),
2652 stabilize_reference_1 (TREE_OPERAND (ref, 1)));
2656 /* We cannot wrap the first expression in a SAVE_EXPR, as then
2657 it wouldn't be ignored. This matters when dealing with
2659 return stabilize_reference_1 (ref);
2662 result = build1 (INDIRECT_REF, TREE_TYPE (ref),
2663 save_expr (build1 (ADDR_EXPR,
2664 build_pointer_type (TREE_TYPE (ref)),
2669 /* If arg isn't a kind of lvalue we recognize, make no change.
2670 Caller should recognize the error for an invalid lvalue. */
2675 return error_mark_node;
2678 TREE_TYPE (result) = TREE_TYPE (ref);
2679 TREE_READONLY (result) = TREE_READONLY (ref);
2680 TREE_SIDE_EFFECTS (result) = TREE_SIDE_EFFECTS (ref);
2681 TREE_THIS_VOLATILE (result) = TREE_THIS_VOLATILE (ref);
2682 TREE_RAISES (result) = TREE_RAISES (ref);
2687 /* Subroutine of stabilize_reference; this is called for subtrees of
2688 references. Any expression with side-effects must be put in a SAVE_EXPR
2689 to ensure that it is only evaluated once.
2691 We don't put SAVE_EXPR nodes around everything, because assigning very
2692 simple expressions to temporaries causes us to miss good opportunities
2693 for optimizations. Among other things, the opportunity to fold in the
2694 addition of a constant into an addressing mode often gets lost, e.g.
2695 "y[i+1] += x;". In general, we take the approach that we should not make
2696 an assignment unless we are forced into it - i.e., that any non-side effect
2697 operator should be allowed, and that cse should take care of coalescing
2698 multiple utterances of the same expression should that prove fruitful. */
2701 stabilize_reference_1 (e)
2704 register tree result;
2705 register enum tree_code code = TREE_CODE (e);
2707 /* We cannot ignore const expressions because it might be a reference
2708 to a const array but whose index contains side-effects. But we can
2709 ignore things that are actual constant or that already have been
2710 handled by this function. */
2712 if (TREE_CONSTANT (e) || code == SAVE_EXPR)
2715 switch (TREE_CODE_CLASS (code))
2725 /* If the expression has side-effects, then encase it in a SAVE_EXPR
2726 so that it will only be evaluated once. */
2727 /* The reference (r) and comparison (<) classes could be handled as
2728 below, but it is generally faster to only evaluate them once. */
2729 if (TREE_SIDE_EFFECTS (e))
2730 return save_expr (e);
2734 /* Constants need no processing. In fact, we should never reach
2739 /* Division is slow and tends to be compiled with jumps,
2740 especially the division by powers of 2 that is often
2741 found inside of an array reference. So do it just once. */
2742 if (code == TRUNC_DIV_EXPR || code == TRUNC_MOD_EXPR
2743 || code == FLOOR_DIV_EXPR || code == FLOOR_MOD_EXPR
2744 || code == CEIL_DIV_EXPR || code == CEIL_MOD_EXPR
2745 || code == ROUND_DIV_EXPR || code == ROUND_MOD_EXPR)
2746 return save_expr (e);
2747 /* Recursively stabilize each operand. */
2748 result = build_nt (code, stabilize_reference_1 (TREE_OPERAND (e, 0)),
2749 stabilize_reference_1 (TREE_OPERAND (e, 1)));
2753 /* Recursively stabilize each operand. */
2754 result = build_nt (code, stabilize_reference_1 (TREE_OPERAND (e, 0)));
2761 TREE_TYPE (result) = TREE_TYPE (e);
2762 TREE_READONLY (result) = TREE_READONLY (e);
2763 TREE_SIDE_EFFECTS (result) = TREE_SIDE_EFFECTS (e);
2764 TREE_THIS_VOLATILE (result) = TREE_THIS_VOLATILE (e);
2765 TREE_RAISES (result) = TREE_RAISES (e);
2770 /* Low-level constructors for expressions. */
2772 /* Build an expression of code CODE, data type TYPE,
2773 and operands as specified by the arguments ARG1 and following arguments.
2774 Expressions and reference nodes can be created this way.
2775 Constants, decls, types and misc nodes cannot be. */
2778 build VPROTO((enum tree_code code, tree tt, ...))
2781 enum tree_code code;
2786 register int length;
2792 code = va_arg (p, enum tree_code);
2793 tt = va_arg (p, tree);
2796 t = make_node (code);
2797 length = tree_code_length[(int) code];
2802 /* This is equivalent to the loop below, but faster. */
2803 register tree arg0 = va_arg (p, tree);
2804 register tree arg1 = va_arg (p, tree);
2805 TREE_OPERAND (t, 0) = arg0;
2806 TREE_OPERAND (t, 1) = arg1;
2807 if ((arg0 && TREE_SIDE_EFFECTS (arg0))
2808 || (arg1 && TREE_SIDE_EFFECTS (arg1)))
2809 TREE_SIDE_EFFECTS (t) = 1;
2811 = (arg0 && TREE_RAISES (arg0)) || (arg1 && TREE_RAISES (arg1));
2813 else if (length == 1)
2815 register tree arg0 = va_arg (p, tree);
2817 /* Call build1 for this! */
2818 if (TREE_CODE_CLASS (code) != 's')
2820 TREE_OPERAND (t, 0) = arg0;
2821 if (arg0 && TREE_SIDE_EFFECTS (arg0))
2822 TREE_SIDE_EFFECTS (t) = 1;
2823 TREE_RAISES (t) = (arg0 && TREE_RAISES (arg0));
2827 for (i = 0; i < length; i++)
2829 register tree operand = va_arg (p, tree);
2830 TREE_OPERAND (t, i) = operand;
2833 if (TREE_SIDE_EFFECTS (operand))
2834 TREE_SIDE_EFFECTS (t) = 1;
2835 if (TREE_RAISES (operand))
2836 TREE_RAISES (t) = 1;
2844 /* Same as above, but only builds for unary operators.
2845 Saves lions share of calls to `build'; cuts down use
2846 of varargs, which is expensive for RISC machines. */
2849 build1 (code, type, node)
2850 enum tree_code code;
2854 register struct obstack *obstack = expression_obstack;
2855 register int i, length;
2856 register tree_node_kind kind;
2859 #ifdef GATHER_STATISTICS
2860 if (TREE_CODE_CLASS (code) == 'r')
2866 length = sizeof (struct tree_exp);
2868 t = (tree) obstack_alloc (obstack, length);
2870 #ifdef GATHER_STATISTICS
2871 tree_node_counts[(int)kind]++;
2872 tree_node_sizes[(int)kind] += length;
2875 for (i = (length / sizeof (int)) - 1; i >= 0; i--)
2878 TREE_TYPE (t) = type;
2879 TREE_SET_CODE (t, code);
2881 if (obstack == &permanent_obstack)
2882 TREE_PERMANENT (t) = 1;
2884 TREE_OPERAND (t, 0) = node;
2887 if (TREE_SIDE_EFFECTS (node))
2888 TREE_SIDE_EFFECTS (t) = 1;
2889 if (TREE_RAISES (node))
2890 TREE_RAISES (t) = 1;
2896 /* Similar except don't specify the TREE_TYPE
2897 and leave the TREE_SIDE_EFFECTS as 0.
2898 It is permissible for arguments to be null,
2899 or even garbage if their values do not matter. */
2902 build_nt VPROTO((enum tree_code code, ...))
2905 enum tree_code code;
2909 register int length;
2915 code = va_arg (p, enum tree_code);
2918 t = make_node (code);
2919 length = tree_code_length[(int) code];
2921 for (i = 0; i < length; i++)
2922 TREE_OPERAND (t, i) = va_arg (p, tree);
2928 /* Similar to `build_nt', except we build
2929 on the temp_decl_obstack, regardless. */
2932 build_parse_node VPROTO((enum tree_code code, ...))
2935 enum tree_code code;
2937 register struct obstack *ambient_obstack = expression_obstack;
2940 register int length;
2946 code = va_arg (p, enum tree_code);
2949 expression_obstack = &temp_decl_obstack;
2951 t = make_node (code);
2952 length = tree_code_length[(int) code];
2954 for (i = 0; i < length; i++)
2955 TREE_OPERAND (t, i) = va_arg (p, tree);
2958 expression_obstack = ambient_obstack;
2963 /* Commented out because this wants to be done very
2964 differently. See cp-lex.c. */
2966 build_op_identifier (op1, op2)
2969 register tree t = make_node (OP_IDENTIFIER);
2970 TREE_PURPOSE (t) = op1;
2971 TREE_VALUE (t) = op2;
2976 /* Create a DECL_... node of code CODE, name NAME and data type TYPE.
2977 We do NOT enter this node in any sort of symbol table.
2979 layout_decl is used to set up the decl's storage layout.
2980 Other slots are initialized to 0 or null pointers. */
2983 build_decl (code, name, type)
2984 enum tree_code code;
2989 t = make_node (code);
2991 /* if (type == error_mark_node)
2992 type = integer_type_node; */
2993 /* That is not done, deliberately, so that having error_mark_node
2994 as the type can suppress useless errors in the use of this variable. */
2996 DECL_NAME (t) = name;
2997 DECL_ASSEMBLER_NAME (t) = name;
2998 TREE_TYPE (t) = type;
3000 if (code == VAR_DECL || code == PARM_DECL || code == RESULT_DECL)
3002 else if (code == FUNCTION_DECL)
3003 DECL_MODE (t) = FUNCTION_MODE;
3008 /* BLOCK nodes are used to represent the structure of binding contours
3009 and declarations, once those contours have been exited and their contents
3010 compiled. This information is used for outputting debugging info. */
3013 build_block (vars, tags, subblocks, supercontext, chain)
3014 tree vars, tags, subblocks, supercontext, chain;
3016 register tree block = make_node (BLOCK);
3017 BLOCK_VARS (block) = vars;
3018 BLOCK_TYPE_TAGS (block) = tags;
3019 BLOCK_SUBBLOCKS (block) = subblocks;
3020 BLOCK_SUPERCONTEXT (block) = supercontext;
3021 BLOCK_CHAIN (block) = chain;
3025 /* Return a declaration like DDECL except that its DECL_MACHINE_ATTRIBUTE
3029 build_decl_attribute_variant (ddecl, attribute)
3030 tree ddecl, attribute;
3032 DECL_MACHINE_ATTRIBUTES (ddecl) = attribute;
3036 /* Return a type like TTYPE except that its TYPE_ATTRIBUTE
3039 Record such modified types already made so we don't make duplicates. */
3042 build_type_attribute_variant (ttype, attribute)
3043 tree ttype, attribute;
3045 if ( ! attribute_list_equal (TYPE_ATTRIBUTES (ttype), attribute))
3047 register int hashcode;
3048 register struct obstack *ambient_obstack = current_obstack;
3051 if (ambient_obstack != &permanent_obstack)
3052 current_obstack = TYPE_OBSTACK (ttype);
3054 ntype = copy_node (ttype);
3055 current_obstack = ambient_obstack;
3057 TYPE_POINTER_TO (ntype) = 0;
3058 TYPE_REFERENCE_TO (ntype) = 0;
3059 TYPE_ATTRIBUTES (ntype) = attribute;
3061 /* Create a new main variant of TYPE. */
3062 TYPE_MAIN_VARIANT (ntype) = ntype;
3063 TYPE_NEXT_VARIANT (ntype) = 0;
3064 TYPE_READONLY (ntype) = TYPE_VOLATILE (ntype) = 0;
3066 hashcode = TYPE_HASH (TREE_CODE (ntype))
3067 + TYPE_HASH (TREE_TYPE (ntype))
3068 + attribute_hash_list (attribute);
3070 switch (TREE_CODE (ntype))
3073 hashcode += TYPE_HASH (TYPE_ARG_TYPES (ntype));
3076 hashcode += TYPE_HASH (TYPE_DOMAIN (ntype));
3079 hashcode += TYPE_HASH (TYPE_MAX_VALUE (ntype));
3082 hashcode += TYPE_HASH (TYPE_PRECISION (ntype));
3086 ntype = type_hash_canon (hashcode, ntype);
3087 ttype = build_type_variant (ntype, TYPE_READONLY (ttype),
3088 TYPE_VOLATILE (ttype));
3094 /* Return a 1 if ATTR_NAME and ATTR_ARGS is valid for either declaration DECL
3095 or type TYPE and 0 otherwise. Validity is determined the configuration
3096 macros VALID_MACHINE_DECL_ATTRIBUTE and VALID_MACHINE_TYPE_ATTRIBUTE. */
3099 valid_machine_attribute (attr_name, attr_args, decl, type)
3100 tree attr_name, attr_args;
3105 tree decl_attr_list = decl != 0 ? DECL_MACHINE_ATTRIBUTES (decl) : 0;
3106 tree type_attr_list = TYPE_ATTRIBUTES (type);
3108 if (TREE_CODE (attr_name) != IDENTIFIER_NODE)
3111 #ifdef VALID_MACHINE_DECL_ATTRIBUTE
3113 && VALID_MACHINE_DECL_ATTRIBUTE (decl, decl_attr_list, attr_name, attr_args))
3115 tree attr = lookup_attribute (IDENTIFIER_POINTER (attr_name),
3118 if (attr != NULL_TREE)
3120 /* Override existing arguments. Declarations are unique so we can
3121 modify this in place. */
3122 TREE_VALUE (attr) = attr_args;
3126 decl_attr_list = tree_cons (attr_name, attr_args, decl_attr_list);
3127 decl = build_decl_attribute_variant (decl, decl_attr_list);
3134 #ifdef VALID_MACHINE_TYPE_ATTRIBUTE
3135 if (VALID_MACHINE_TYPE_ATTRIBUTE (type, type_attr_list, attr_name, attr_args))
3137 tree attr = lookup_attribute (IDENTIFIER_POINTER (attr_name),
3140 if (attr != NULL_TREE)
3142 /* Override existing arguments.
3143 ??? This currently works since attribute arguments are not
3144 included in `attribute_hash_list'. Something more complicated
3145 may be needed in the future. */
3146 TREE_VALUE (attr) = attr_args;
3150 type_attr_list = tree_cons (attr_name, attr_args, type_attr_list);
3151 type = build_type_attribute_variant (type, type_attr_list);
3154 TREE_TYPE (decl) = type;
3158 /* Handle putting a type attribute on pointer-to-function-type by putting
3159 the attribute on the function type. */
3160 else if (TREE_CODE (type) == POINTER_TYPE
3161 && TREE_CODE (TREE_TYPE (type)) == FUNCTION_TYPE
3162 && VALID_MACHINE_TYPE_ATTRIBUTE (TREE_TYPE (type), type_attr_list,
3163 attr_name, attr_args))
3165 tree inner_type = TREE_TYPE (type);
3166 tree inner_attr_list = TYPE_ATTRIBUTES (inner_type);
3167 tree attr = lookup_attribute (IDENTIFIER_POINTER (attr_name),
3170 if (attr != NULL_TREE)
3171 TREE_VALUE (attr) = attr_args;
3174 inner_attr_list = tree_cons (attr_name, attr_args, inner_attr_list);
3175 inner_type = build_type_attribute_variant (inner_type,
3180 TREE_TYPE (decl) = build_pointer_type (inner_type);
3189 /* Return non-zero if IDENT is a valid name for attribute ATTR,
3192 We try both `text' and `__text__', ATTR may be either one. */
3193 /* ??? It might be a reasonable simplification to require ATTR to be only
3194 `text'. One might then also require attribute lists to be stored in
3195 their canonicalized form. */
3198 is_attribute_p (attr, ident)
3202 int ident_len, attr_len;
3205 if (TREE_CODE (ident) != IDENTIFIER_NODE)
3208 if (strcmp (attr, IDENTIFIER_POINTER (ident)) == 0)
3211 p = IDENTIFIER_POINTER (ident);
3212 ident_len = strlen (p);
3213 attr_len = strlen (attr);
3215 /* If ATTR is `__text__', IDENT must be `text'; and vice versa. */
3219 || attr[attr_len - 2] != '_'
3220 || attr[attr_len - 1] != '_')
3222 if (ident_len == attr_len - 4
3223 && strncmp (attr + 2, p, attr_len - 4) == 0)
3228 if (ident_len == attr_len + 4
3229 && p[0] == '_' && p[1] == '_'
3230 && p[ident_len - 2] == '_' && p[ident_len - 1] == '_'
3231 && strncmp (attr, p + 2, attr_len) == 0)
3238 /* Given an attribute name and a list of attributes, return a pointer to the
3239 attribute's list element if the attribute is part of the list, or NULL_TREE
3243 lookup_attribute (attr_name, list)
3249 for (l = list; l; l = TREE_CHAIN (l))
3251 if (TREE_CODE (TREE_PURPOSE (l)) != IDENTIFIER_NODE)
3253 if (is_attribute_p (attr_name, TREE_PURPOSE (l)))
3260 /* Return an attribute list that is the union of a1 and a2. */
3263 merge_attributes (a1, a2)
3264 register tree a1, a2;
3268 /* Either one unset? Take the set one. */
3270 if (! (attributes = a1))
3273 /* One that completely contains the other? Take it. */
3275 else if (a2 && ! attribute_list_contained (a1, a2))
3276 if (attribute_list_contained (a2, a1))
3280 /* Pick the longest list, and hang on the other list. */
3281 /* ??? For the moment we punt on the issue of attrs with args. */
3283 if (list_length (a1) < list_length (a2))
3284 attributes = a2, a2 = a1;
3286 for (; a2; a2 = TREE_CHAIN (a2))
3287 if (lookup_attribute (IDENTIFIER_POINTER (TREE_PURPOSE (a2)),
3288 attributes) == NULL_TREE)
3290 a1 = copy_node (a2);
3291 TREE_CHAIN (a1) = attributes;
3298 /* Return a type like TYPE except that its TYPE_READONLY is CONSTP
3299 and its TYPE_VOLATILE is VOLATILEP.
3301 Such variant types already made are recorded so that duplicates
3304 A variant types should never be used as the type of an expression.
3305 Always copy the variant information into the TREE_READONLY
3306 and TREE_THIS_VOLATILE of the expression, and then give the expression
3307 as its type the "main variant", the variant whose TYPE_READONLY
3308 and TYPE_VOLATILE are zero. Use TYPE_MAIN_VARIANT to find the
3312 build_type_variant (type, constp, volatilep)
3314 int constp, volatilep;
3318 /* Treat any nonzero argument as 1. */
3320 volatilep = !!volatilep;
3322 /* Search the chain of variants to see if there is already one there just
3323 like the one we need to have. If so, use that existing one. We must
3324 preserve the TYPE_NAME, since there is code that depends on this. */
3326 for (t = TYPE_MAIN_VARIANT (type); t; t = TYPE_NEXT_VARIANT (t))
3327 if (constp == TYPE_READONLY (t) && volatilep == TYPE_VOLATILE (t)
3328 && TYPE_NAME (t) == TYPE_NAME (type))
3331 /* We need a new one. */
3333 t = build_type_copy (type);
3334 TYPE_READONLY (t) = constp;
3335 TYPE_VOLATILE (t) = volatilep;
3340 /* Create a new variant of TYPE, equivalent but distinct.
3341 This is so the caller can modify it. */
3344 build_type_copy (type)
3347 register tree t, m = TYPE_MAIN_VARIANT (type);
3348 register struct obstack *ambient_obstack = current_obstack;
3350 current_obstack = TYPE_OBSTACK (type);
3351 t = copy_node (type);
3352 current_obstack = ambient_obstack;
3354 TYPE_POINTER_TO (t) = 0;
3355 TYPE_REFERENCE_TO (t) = 0;
3357 /* Add this type to the chain of variants of TYPE. */
3358 TYPE_NEXT_VARIANT (t) = TYPE_NEXT_VARIANT (m);
3359 TYPE_NEXT_VARIANT (m) = t;
3364 /* Hashing of types so that we don't make duplicates.
3365 The entry point is `type_hash_canon'. */
3367 /* Each hash table slot is a bucket containing a chain
3368 of these structures. */
3372 struct type_hash *next; /* Next structure in the bucket. */
3373 int hashcode; /* Hash code of this type. */
3374 tree type; /* The type recorded here. */
3377 /* Now here is the hash table. When recording a type, it is added
3378 to the slot whose index is the hash code mod the table size.
3379 Note that the hash table is used for several kinds of types
3380 (function types, array types and array index range types, for now).
3381 While all these live in the same table, they are completely independent,
3382 and the hash code is computed differently for each of these. */
3384 #define TYPE_HASH_SIZE 59
3385 struct type_hash *type_hash_table[TYPE_HASH_SIZE];
3387 /* Compute a hash code for a list of types (chain of TREE_LIST nodes
3388 with types in the TREE_VALUE slots), by adding the hash codes
3389 of the individual types. */
3392 type_hash_list (list)
3395 register int hashcode;
3397 for (hashcode = 0, tail = list; tail; tail = TREE_CHAIN (tail))
3398 hashcode += TYPE_HASH (TREE_VALUE (tail));
3402 /* Look in the type hash table for a type isomorphic to TYPE.
3403 If one is found, return it. Otherwise return 0. */
3406 type_hash_lookup (hashcode, type)
3410 register struct type_hash *h;
3411 for (h = type_hash_table[hashcode % TYPE_HASH_SIZE]; h; h = h->next)
3412 if (h->hashcode == hashcode
3413 && TREE_CODE (h->type) == TREE_CODE (type)
3414 && TREE_TYPE (h->type) == TREE_TYPE (type)
3415 && attribute_list_equal (TYPE_ATTRIBUTES (h->type),
3416 TYPE_ATTRIBUTES (type))
3417 && (TYPE_MAX_VALUE (h->type) == TYPE_MAX_VALUE (type)
3418 || tree_int_cst_equal (TYPE_MAX_VALUE (h->type),
3419 TYPE_MAX_VALUE (type)))
3420 && (TYPE_MIN_VALUE (h->type) == TYPE_MIN_VALUE (type)
3421 || tree_int_cst_equal (TYPE_MIN_VALUE (h->type),
3422 TYPE_MIN_VALUE (type)))
3423 /* Note that TYPE_DOMAIN is TYPE_ARG_TYPES for FUNCTION_TYPE. */
3424 && (TYPE_DOMAIN (h->type) == TYPE_DOMAIN (type)
3425 || (TYPE_DOMAIN (h->type)
3426 && TREE_CODE (TYPE_DOMAIN (h->type)) == TREE_LIST
3427 && TYPE_DOMAIN (type)
3428 && TREE_CODE (TYPE_DOMAIN (type)) == TREE_LIST
3429 && type_list_equal (TYPE_DOMAIN (h->type),
3430 TYPE_DOMAIN (type)))))
3435 /* Add an entry to the type-hash-table
3436 for a type TYPE whose hash code is HASHCODE. */
3439 type_hash_add (hashcode, type)
3443 register struct type_hash *h;
3445 h = (struct type_hash *) oballoc (sizeof (struct type_hash));
3446 h->hashcode = hashcode;
3448 h->next = type_hash_table[hashcode % TYPE_HASH_SIZE];
3449 type_hash_table[hashcode % TYPE_HASH_SIZE] = h;
3452 /* Given TYPE, and HASHCODE its hash code, return the canonical
3453 object for an identical type if one already exists.
3454 Otherwise, return TYPE, and record it as the canonical object
3455 if it is a permanent object.
3457 To use this function, first create a type of the sort you want.
3458 Then compute its hash code from the fields of the type that
3459 make it different from other similar types.
3460 Then call this function and use the value.
3461 This function frees the type you pass in if it is a duplicate. */
3463 /* Set to 1 to debug without canonicalization. Never set by program. */
3464 int debug_no_type_hash = 0;
3467 type_hash_canon (hashcode, type)
3473 if (debug_no_type_hash)
3476 t1 = type_hash_lookup (hashcode, type);
3479 obstack_free (TYPE_OBSTACK (type), type);
3480 #ifdef GATHER_STATISTICS
3481 tree_node_counts[(int)t_kind]--;
3482 tree_node_sizes[(int)t_kind] -= sizeof (struct tree_type);
3487 /* If this is a permanent type, record it for later reuse. */
3488 if (TREE_PERMANENT (type))
3489 type_hash_add (hashcode, type);
3494 /* Compute a hash code for a list of attributes (chain of TREE_LIST nodes
3495 with names in the TREE_PURPOSE slots and args in the TREE_VALUE slots),
3496 by adding the hash codes of the individual attributes. */
3499 attribute_hash_list (list)
3502 register int hashcode;
3504 for (hashcode = 0, tail = list; tail; tail = TREE_CHAIN (tail))
3505 /* ??? Do we want to add in TREE_VALUE too? */
3506 hashcode += TYPE_HASH (TREE_PURPOSE (tail));
3510 /* Given two lists of attributes, return true if list l2 is
3511 equivalent to l1. */
3514 attribute_list_equal (l1, l2)
3517 return attribute_list_contained (l1, l2)
3518 && attribute_list_contained (l2, l1);
3521 /* Given two lists of attributes, return true if list L2 is
3522 completely contained within L1. */
3523 /* ??? This would be faster if attribute names were stored in a canonicalized
3524 form. Otherwise, if L1 uses `foo' and L2 uses `__foo__', the long method
3525 must be used to show these elements are equivalent (which they are). */
3526 /* ??? It's not clear that attributes with arguments will always be handled
3530 attribute_list_contained (l1, l2)
3533 register tree t1, t2;
3535 /* First check the obvious, maybe the lists are identical. */
3539 /* Maybe the lists are similar. */
3540 for (t1 = l1, t2 = l2;
3542 && TREE_PURPOSE (t1) == TREE_PURPOSE (t2)
3543 && TREE_VALUE (t1) == TREE_VALUE (t2);
3544 t1 = TREE_CHAIN (t1), t2 = TREE_CHAIN (t2));
3546 /* Maybe the lists are equal. */
3547 if (t1 == 0 && t2 == 0)
3550 for (; t2; t2 = TREE_CHAIN (t2))
3553 = lookup_attribute (IDENTIFIER_POINTER (TREE_PURPOSE (t2)), l1);
3555 if (attr == NULL_TREE)
3557 if (simple_cst_equal (TREE_VALUE (t2), TREE_VALUE (attr)) != 1)
3564 /* Given two lists of types
3565 (chains of TREE_LIST nodes with types in the TREE_VALUE slots)
3566 return 1 if the lists contain the same types in the same order.
3567 Also, the TREE_PURPOSEs must match. */
3570 type_list_equal (l1, l2)
3573 register tree t1, t2;
3575 for (t1 = l1, t2 = l2; t1 && t2; t1 = TREE_CHAIN (t1), t2 = TREE_CHAIN (t2))
3576 if (TREE_VALUE (t1) != TREE_VALUE (t2)
3577 || (TREE_PURPOSE (t1) != TREE_PURPOSE (t2)
3578 && ! (1 == simple_cst_equal (TREE_PURPOSE (t1), TREE_PURPOSE (t2))
3579 && (TREE_TYPE (TREE_PURPOSE (t1))
3580 == TREE_TYPE (TREE_PURPOSE (t2))))))
3586 /* Nonzero if integer constants T1 and T2
3587 represent the same constant value. */
3590 tree_int_cst_equal (t1, t2)
3595 if (t1 == 0 || t2 == 0)
3597 if (TREE_CODE (t1) == INTEGER_CST
3598 && TREE_CODE (t2) == INTEGER_CST
3599 && TREE_INT_CST_LOW (t1) == TREE_INT_CST_LOW (t2)
3600 && TREE_INT_CST_HIGH (t1) == TREE_INT_CST_HIGH (t2))
3605 /* Nonzero if integer constants T1 and T2 represent values that satisfy <.
3606 The precise way of comparison depends on their data type. */
3609 tree_int_cst_lt (t1, t2)
3615 if (!TREE_UNSIGNED (TREE_TYPE (t1)))
3616 return INT_CST_LT (t1, t2);
3617 return INT_CST_LT_UNSIGNED (t1, t2);
3620 /* Return an indication of the sign of the integer constant T.
3621 The return value is -1 if T < 0, 0 if T == 0, and 1 if T > 0.
3622 Note that -1 will never be returned it T's type is unsigned. */
3625 tree_int_cst_sgn (t)
3628 if (TREE_INT_CST_LOW (t) == 0 && TREE_INT_CST_HIGH (t) == 0)
3630 else if (TREE_UNSIGNED (TREE_TYPE (t)))
3632 else if (TREE_INT_CST_HIGH (t) < 0)
3638 /* Compare two constructor-element-type constants. Return 1 if the lists
3639 are known to be equal; otherwise return 0. */
3642 simple_cst_list_equal (l1, l2)
3645 while (l1 != NULL_TREE && l2 != NULL_TREE)
3647 if (simple_cst_equal (TREE_VALUE (l1), TREE_VALUE (l2)) != 1)
3650 l1 = TREE_CHAIN (l1);
3651 l2 = TREE_CHAIN (l2);
3657 /* Return truthvalue of whether T1 is the same tree structure as T2.
3658 Return 1 if they are the same.
3659 Return 0 if they are understandably different.
3660 Return -1 if either contains tree structure not understood by
3664 simple_cst_equal (t1, t2)
3667 register enum tree_code code1, code2;
3672 if (t1 == 0 || t2 == 0)
3675 code1 = TREE_CODE (t1);
3676 code2 = TREE_CODE (t2);
3678 if (code1 == NOP_EXPR || code1 == CONVERT_EXPR || code1 == NON_LVALUE_EXPR)
3679 if (code2 == NOP_EXPR || code2 == CONVERT_EXPR || code2 == NON_LVALUE_EXPR)
3680 return simple_cst_equal (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0));
3682 return simple_cst_equal (TREE_OPERAND (t1, 0), t2);
3683 else if (code2 == NOP_EXPR || code2 == CONVERT_EXPR
3684 || code2 == NON_LVALUE_EXPR)
3685 return simple_cst_equal (t1, TREE_OPERAND (t2, 0));
3693 return TREE_INT_CST_LOW (t1) == TREE_INT_CST_LOW (t2)
3694 && TREE_INT_CST_HIGH (t1) == TREE_INT_CST_HIGH (t2);
3697 return REAL_VALUES_EQUAL (TREE_REAL_CST (t1), TREE_REAL_CST (t2));
3700 return TREE_STRING_LENGTH (t1) == TREE_STRING_LENGTH (t2)
3701 && !bcmp (TREE_STRING_POINTER (t1), TREE_STRING_POINTER (t2),
3702 TREE_STRING_LENGTH (t1));
3708 return simple_cst_equal (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0));
3711 cmp = simple_cst_equal (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0));
3714 return simple_cst_list_equal (TREE_OPERAND (t1, 1), TREE_OPERAND (t2, 1));
3717 /* Special case: if either target is an unallocated VAR_DECL,
3718 it means that it's going to be unified with whatever the
3719 TARGET_EXPR is really supposed to initialize, so treat it
3720 as being equivalent to anything. */
3721 if ((TREE_CODE (TREE_OPERAND (t1, 0)) == VAR_DECL
3722 && DECL_NAME (TREE_OPERAND (t1, 0)) == NULL_TREE
3723 && DECL_RTL (TREE_OPERAND (t1, 0)) == 0)
3724 || (TREE_CODE (TREE_OPERAND (t2, 0)) == VAR_DECL
3725 && DECL_NAME (TREE_OPERAND (t2, 0)) == NULL_TREE
3726 && DECL_RTL (TREE_OPERAND (t2, 0)) == 0))
3729 cmp = simple_cst_equal (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0));
3732 return simple_cst_equal (TREE_OPERAND (t1, 1), TREE_OPERAND (t2, 1));
3734 case WITH_CLEANUP_EXPR:
3735 cmp = simple_cst_equal (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0));
3738 return simple_cst_equal (TREE_OPERAND (t1, 2), TREE_OPERAND (t1, 2));
3741 if (TREE_OPERAND (t1, 1) == TREE_OPERAND (t2, 1))
3742 return simple_cst_equal (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0));
3752 /* This general rule works for most tree codes. All exceptions should be
3753 handled above. If this is a language-specific tree code, we can't
3754 trust what might be in the operand, so say we don't know
3757 >= sizeof standard_tree_code_type / sizeof standard_tree_code_type[0])
3760 switch (TREE_CODE_CLASS (code1))
3770 for (i=0; i<tree_code_length[(int) code1]; ++i)
3772 cmp = simple_cst_equal (TREE_OPERAND (t1, i), TREE_OPERAND (t2, i));
3782 /* Constructors for pointer, array and function types.
3783 (RECORD_TYPE, UNION_TYPE and ENUMERAL_TYPE nodes are
3784 constructed by language-dependent code, not here.) */
3786 /* Construct, lay out and return the type of pointers to TO_TYPE.
3787 If such a type has already been constructed, reuse it. */
3790 build_pointer_type (to_type)
3793 register tree t = TYPE_POINTER_TO (to_type);
3795 /* First, if we already have a type for pointers to TO_TYPE, use it. */
3800 /* We need a new one. Put this in the same obstack as TO_TYPE. */
3801 push_obstacks (TYPE_OBSTACK (to_type), TYPE_OBSTACK (to_type));
3802 t = make_node (POINTER_TYPE);
3805 TREE_TYPE (t) = to_type;
3807 /* Record this type as the pointer to TO_TYPE. */
3808 TYPE_POINTER_TO (to_type) = t;
3810 /* Lay out the type. This function has many callers that are concerned
3811 with expression-construction, and this simplifies them all.
3812 Also, it guarantees the TYPE_SIZE is in the same obstack as the type. */
3818 /* Create a type of integers to be the TYPE_DOMAIN of an ARRAY_TYPE.
3819 MAXVAL should be the maximum value in the domain
3820 (one less than the length of the array). */
3823 build_index_type (maxval)
3826 register tree itype = make_node (INTEGER_TYPE);
3828 TYPE_PRECISION (itype) = TYPE_PRECISION (sizetype);
3829 TYPE_MIN_VALUE (itype) = size_zero_node;
3831 push_obstacks (TYPE_OBSTACK (itype), TYPE_OBSTACK (itype));
3832 TYPE_MAX_VALUE (itype) = convert (sizetype, maxval);
3835 TYPE_MODE (itype) = TYPE_MODE (sizetype);
3836 TYPE_SIZE (itype) = TYPE_SIZE (sizetype);
3837 TYPE_ALIGN (itype) = TYPE_ALIGN (sizetype);
3838 if (TREE_CODE (maxval) == INTEGER_CST)
3840 int maxint = (int) TREE_INT_CST_LOW (maxval);
3841 /* If the domain should be empty, make sure the maxval
3842 remains -1 and is not spoiled by truncation. */
3843 if (INT_CST_LT (maxval, integer_zero_node))
3845 TYPE_MAX_VALUE (itype) = build_int_2 (-1, -1);
3846 TREE_TYPE (TYPE_MAX_VALUE (itype)) = sizetype;
3848 return type_hash_canon (maxint < 0 ? ~maxint : maxint, itype);
3854 /* Create a range of some discrete type TYPE (an INTEGER_TYPE,
3855 ENUMERAL_TYPE, BOOLEAN_TYPE, or CHAR_TYPE), with
3856 low bound LOWVAL and high bound HIGHVAL.
3857 if TYPE==NULL_TREE, sizetype is used. */
3860 build_range_type (type, lowval, highval)
3861 tree type, lowval, highval;
3863 register tree itype = make_node (INTEGER_TYPE);
3865 TREE_TYPE (itype) = type;
3866 if (type == NULL_TREE)
3869 push_obstacks (TYPE_OBSTACK (itype), TYPE_OBSTACK (itype));
3870 TYPE_MIN_VALUE (itype) = convert (type, lowval);
3871 TYPE_MAX_VALUE (itype) = convert (type, highval);
3874 TYPE_PRECISION (itype) = TYPE_PRECISION (type);
3875 TYPE_MODE (itype) = TYPE_MODE (type);
3876 TYPE_SIZE (itype) = TYPE_SIZE (type);
3877 TYPE_ALIGN (itype) = TYPE_ALIGN (type);
3878 if ((TREE_CODE (lowval) == INTEGER_CST)
3879 && (TREE_CODE (highval) == INTEGER_CST))
3881 HOST_WIDE_INT highint = TREE_INT_CST_LOW (highval);
3882 HOST_WIDE_INT lowint = TREE_INT_CST_LOW (lowval);
3883 int maxint = (int) (highint - lowint);
3884 return type_hash_canon (maxint < 0 ? ~maxint : maxint, itype);
3890 /* Just like build_index_type, but takes lowval and highval instead
3891 of just highval (maxval). */
3894 build_index_2_type (lowval,highval)
3895 tree lowval, highval;
3897 return build_range_type (NULL_TREE, lowval, highval);
3900 /* Return nonzero iff ITYPE1 and ITYPE2 are equal (in the LISP sense).
3901 Needed because when index types are not hashed, equal index types
3902 built at different times appear distinct, even though structurally,
3906 index_type_equal (itype1, itype2)
3907 tree itype1, itype2;
3909 if (TREE_CODE (itype1) != TREE_CODE (itype2))
3911 if (TREE_CODE (itype1) == INTEGER_TYPE)
3913 if (TYPE_PRECISION (itype1) != TYPE_PRECISION (itype2)
3914 || TYPE_MODE (itype1) != TYPE_MODE (itype2)
3915 || simple_cst_equal (TYPE_SIZE (itype1), TYPE_SIZE (itype2)) != 1
3916 || TYPE_ALIGN (itype1) != TYPE_ALIGN (itype2))
3918 if (1 == simple_cst_equal (TYPE_MIN_VALUE (itype1),
3919 TYPE_MIN_VALUE (itype2))
3920 && 1 == simple_cst_equal (TYPE_MAX_VALUE (itype1),
3921 TYPE_MAX_VALUE (itype2)))
3928 /* Construct, lay out and return the type of arrays of elements with ELT_TYPE
3929 and number of elements specified by the range of values of INDEX_TYPE.
3930 If such a type has already been constructed, reuse it. */
3933 build_array_type (elt_type, index_type)
3934 tree elt_type, index_type;
3939 if (TREE_CODE (elt_type) == FUNCTION_TYPE)
3941 error ("arrays of functions are not meaningful");
3942 elt_type = integer_type_node;
3945 /* Make sure TYPE_POINTER_TO (elt_type) is filled in. */
3946 build_pointer_type (elt_type);
3948 /* Allocate the array after the pointer type,
3949 in case we free it in type_hash_canon. */
3950 t = make_node (ARRAY_TYPE);
3951 TREE_TYPE (t) = elt_type;
3952 TYPE_DOMAIN (t) = index_type;
3954 if (index_type == 0)
3959 hashcode = TYPE_HASH (elt_type) + TYPE_HASH (index_type);
3960 t = type_hash_canon (hashcode, t);
3962 if (TYPE_SIZE (t) == 0)
3967 /* Construct, lay out and return
3968 the type of functions returning type VALUE_TYPE
3969 given arguments of types ARG_TYPES.
3970 ARG_TYPES is a chain of TREE_LIST nodes whose TREE_VALUEs
3971 are data type nodes for the arguments of the function.
3972 If such a type has already been constructed, reuse it. */
3975 build_function_type (value_type, arg_types)
3976 tree value_type, arg_types;
3981 if (TREE_CODE (value_type) == FUNCTION_TYPE)
3983 error ("function return type cannot be function");
3984 value_type = integer_type_node;
3987 /* Make a node of the sort we want. */
3988 t = make_node (FUNCTION_TYPE);
3989 TREE_TYPE (t) = value_type;
3990 TYPE_ARG_TYPES (t) = arg_types;
3992 /* If we already have such a type, use the old one and free this one. */
3993 hashcode = TYPE_HASH (value_type) + type_hash_list (arg_types);
3994 t = type_hash_canon (hashcode, t);
3996 if (TYPE_SIZE (t) == 0)
4001 /* Build the node for the type of references-to-TO_TYPE. */
4004 build_reference_type (to_type)
4007 register tree t = TYPE_REFERENCE_TO (to_type);
4008 register struct obstack *ambient_obstack = current_obstack;
4009 register struct obstack *ambient_saveable_obstack = saveable_obstack;
4011 /* First, if we already have a type for pointers to TO_TYPE, use it. */
4016 /* We need a new one. If TO_TYPE is permanent, make this permanent too. */
4017 if (TREE_PERMANENT (to_type))
4019 current_obstack = &permanent_obstack;
4020 saveable_obstack = &permanent_obstack;
4023 t = make_node (REFERENCE_TYPE);
4024 TREE_TYPE (t) = to_type;
4026 /* Record this type as the pointer to TO_TYPE. */
4027 TYPE_REFERENCE_TO (to_type) = t;
4031 current_obstack = ambient_obstack;
4032 saveable_obstack = ambient_saveable_obstack;
4036 /* Construct, lay out and return the type of methods belonging to class
4037 BASETYPE and whose arguments and values are described by TYPE.
4038 If that type exists already, reuse it.
4039 TYPE must be a FUNCTION_TYPE node. */
4042 build_method_type (basetype, type)
4043 tree basetype, type;
4048 /* Make a node of the sort we want. */
4049 t = make_node (METHOD_TYPE);
4051 if (TREE_CODE (type) != FUNCTION_TYPE)
4054 TYPE_METHOD_BASETYPE (t) = TYPE_MAIN_VARIANT (basetype);
4055 TREE_TYPE (t) = TREE_TYPE (type);
4057 /* The actual arglist for this function includes a "hidden" argument
4058 which is "this". Put it into the list of argument types. */
4061 = tree_cons (NULL_TREE,
4062 build_pointer_type (basetype), TYPE_ARG_TYPES (type));
4064 /* If we already have such a type, use the old one and free this one. */
4065 hashcode = TYPE_HASH (basetype) + TYPE_HASH (type);
4066 t = type_hash_canon (hashcode, t);
4068 if (TYPE_SIZE (t) == 0)
4074 /* Construct, lay out and return the type of offsets to a value
4075 of type TYPE, within an object of type BASETYPE.
4076 If a suitable offset type exists already, reuse it. */
4079 build_offset_type (basetype, type)
4080 tree basetype, type;
4085 /* Make a node of the sort we want. */
4086 t = make_node (OFFSET_TYPE);
4088 TYPE_OFFSET_BASETYPE (t) = TYPE_MAIN_VARIANT (basetype);
4089 TREE_TYPE (t) = type;
4091 /* If we already have such a type, use the old one and free this one. */
4092 hashcode = TYPE_HASH (basetype) + TYPE_HASH (type);
4093 t = type_hash_canon (hashcode, t);
4095 if (TYPE_SIZE (t) == 0)
4101 /* Create a complex type whose components are COMPONENT_TYPE. */
4104 build_complex_type (component_type)
4105 tree component_type;
4110 /* Make a node of the sort we want. */
4111 t = make_node (COMPLEX_TYPE);
4113 TREE_TYPE (t) = TYPE_MAIN_VARIANT (component_type);
4114 TYPE_VOLATILE (t) = TYPE_VOLATILE (component_type);
4115 TYPE_READONLY (t) = TYPE_READONLY (component_type);
4117 /* If we already have such a type, use the old one and free this one. */
4118 hashcode = TYPE_HASH (component_type);
4119 t = type_hash_canon (hashcode, t);
4121 if (TYPE_SIZE (t) == 0)
4127 /* Return OP, stripped of any conversions to wider types as much as is safe.
4128 Converting the value back to OP's type makes a value equivalent to OP.
4130 If FOR_TYPE is nonzero, we return a value which, if converted to
4131 type FOR_TYPE, would be equivalent to converting OP to type FOR_TYPE.
4133 If FOR_TYPE is nonzero, unaligned bit-field references may be changed to the
4134 narrowest type that can hold the value, even if they don't exactly fit.
4135 Otherwise, bit-field references are changed to a narrower type
4136 only if they can be fetched directly from memory in that type.
4138 OP must have integer, real or enumeral type. Pointers are not allowed!
4140 There are some cases where the obvious value we could return
4141 would regenerate to OP if converted to OP's type,
4142 but would not extend like OP to wider types.
4143 If FOR_TYPE indicates such extension is contemplated, we eschew such values.
4144 For example, if OP is (unsigned short)(signed char)-1,
4145 we avoid returning (signed char)-1 if FOR_TYPE is int,
4146 even though extending that to an unsigned short would regenerate OP,
4147 since the result of extending (signed char)-1 to (int)
4148 is different from (int) OP. */
4151 get_unwidened (op, for_type)
4155 /* Set UNS initially if converting OP to FOR_TYPE is a zero-extension. */
4156 /* TYPE_PRECISION is safe in place of type_precision since
4157 pointer types are not allowed. */
4158 register tree type = TREE_TYPE (op);
4159 register unsigned final_prec
4160 = TYPE_PRECISION (for_type != 0 ? for_type : type);
4162 = (for_type != 0 && for_type != type
4163 && final_prec > TYPE_PRECISION (type)
4164 && TREE_UNSIGNED (type));
4165 register tree win = op;
4167 while (TREE_CODE (op) == NOP_EXPR)
4169 register int bitschange
4170 = TYPE_PRECISION (TREE_TYPE (op))
4171 - TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (op, 0)));
4173 /* Truncations are many-one so cannot be removed.
4174 Unless we are later going to truncate down even farther. */
4176 && final_prec > TYPE_PRECISION (TREE_TYPE (op)))
4179 /* See what's inside this conversion. If we decide to strip it,
4181 op = TREE_OPERAND (op, 0);
4183 /* If we have not stripped any zero-extensions (uns is 0),
4184 we can strip any kind of extension.
4185 If we have previously stripped a zero-extension,
4186 only zero-extensions can safely be stripped.
4187 Any extension can be stripped if the bits it would produce
4188 are all going to be discarded later by truncating to FOR_TYPE. */
4192 if (! uns || final_prec <= TYPE_PRECISION (TREE_TYPE (op)))
4194 /* TREE_UNSIGNED says whether this is a zero-extension.
4195 Let's avoid computing it if it does not affect WIN
4196 and if UNS will not be needed again. */
4197 if ((uns || TREE_CODE (op) == NOP_EXPR)
4198 && TREE_UNSIGNED (TREE_TYPE (op)))
4206 if (TREE_CODE (op) == COMPONENT_REF
4207 /* Since type_for_size always gives an integer type. */
4208 && TREE_CODE (type) != REAL_TYPE
4209 /* Don't crash if field not layed out yet. */
4210 && DECL_SIZE (TREE_OPERAND (op, 1)) != 0)
4212 unsigned innerprec = TREE_INT_CST_LOW (DECL_SIZE (TREE_OPERAND (op, 1)));
4213 type = type_for_size (innerprec, TREE_UNSIGNED (TREE_OPERAND (op, 1)));
4215 /* We can get this structure field in the narrowest type it fits in.
4216 If FOR_TYPE is 0, do this only for a field that matches the
4217 narrower type exactly and is aligned for it
4218 The resulting extension to its nominal type (a fullword type)
4219 must fit the same conditions as for other extensions. */
4221 if (innerprec < TYPE_PRECISION (TREE_TYPE (op))
4222 && (for_type || ! DECL_BIT_FIELD (TREE_OPERAND (op, 1)))
4223 && (! uns || final_prec <= innerprec
4224 || TREE_UNSIGNED (TREE_OPERAND (op, 1)))
4227 win = build (COMPONENT_REF, type, TREE_OPERAND (op, 0),
4228 TREE_OPERAND (op, 1));
4229 TREE_SIDE_EFFECTS (win) = TREE_SIDE_EFFECTS (op);
4230 TREE_THIS_VOLATILE (win) = TREE_THIS_VOLATILE (op);
4231 TREE_RAISES (win) = TREE_RAISES (op);
4237 /* Return OP or a simpler expression for a narrower value
4238 which can be sign-extended or zero-extended to give back OP.
4239 Store in *UNSIGNEDP_PTR either 1 if the value should be zero-extended
4240 or 0 if the value should be sign-extended. */
4243 get_narrower (op, unsignedp_ptr)
4247 register int uns = 0;
4249 register tree win = op;
4251 while (TREE_CODE (op) == NOP_EXPR)
4253 register int bitschange
4254 = TYPE_PRECISION (TREE_TYPE (op))
4255 - TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (op, 0)));
4257 /* Truncations are many-one so cannot be removed. */
4261 /* See what's inside this conversion. If we decide to strip it,
4263 op = TREE_OPERAND (op, 0);
4267 /* An extension: the outermost one can be stripped,
4268 but remember whether it is zero or sign extension. */
4270 uns = TREE_UNSIGNED (TREE_TYPE (op));
4271 /* Otherwise, if a sign extension has been stripped,
4272 only sign extensions can now be stripped;
4273 if a zero extension has been stripped, only zero-extensions. */
4274 else if (uns != TREE_UNSIGNED (TREE_TYPE (op)))
4278 else /* bitschange == 0 */
4280 /* A change in nominal type can always be stripped, but we must
4281 preserve the unsignedness. */
4283 uns = TREE_UNSIGNED (TREE_TYPE (op));
4290 if (TREE_CODE (op) == COMPONENT_REF
4291 /* Since type_for_size always gives an integer type. */
4292 && TREE_CODE (TREE_TYPE (op)) != REAL_TYPE)
4294 unsigned innerprec = TREE_INT_CST_LOW (DECL_SIZE (TREE_OPERAND (op, 1)));
4295 tree type = type_for_size (innerprec, TREE_UNSIGNED (op));
4297 /* We can get this structure field in a narrower type that fits it,
4298 but the resulting extension to its nominal type (a fullword type)
4299 must satisfy the same conditions as for other extensions.
4301 Do this only for fields that are aligned (not bit-fields),
4302 because when bit-field insns will be used there is no
4303 advantage in doing this. */
4305 if (innerprec < TYPE_PRECISION (TREE_TYPE (op))
4306 && ! DECL_BIT_FIELD (TREE_OPERAND (op, 1))
4307 && (first || uns == TREE_UNSIGNED (TREE_OPERAND (op, 1)))
4311 uns = TREE_UNSIGNED (TREE_OPERAND (op, 1));
4312 win = build (COMPONENT_REF, type, TREE_OPERAND (op, 0),
4313 TREE_OPERAND (op, 1));
4314 TREE_SIDE_EFFECTS (win) = TREE_SIDE_EFFECTS (op);
4315 TREE_THIS_VOLATILE (win) = TREE_THIS_VOLATILE (op);
4316 TREE_RAISES (win) = TREE_RAISES (op);
4319 *unsignedp_ptr = uns;
4323 /* Return the precision of a type, for arithmetic purposes.
4324 Supports all types on which arithmetic is possible
4325 (including pointer types).
4326 It's not clear yet what will be right for complex types. */
4329 type_precision (type)
4332 return ((TREE_CODE (type) == INTEGER_TYPE
4333 || TREE_CODE (type) == ENUMERAL_TYPE
4334 || TREE_CODE (type) == REAL_TYPE)
4335 ? TYPE_PRECISION (type) : POINTER_SIZE);
4338 /* Nonzero if integer constant C has a value that is permissible
4339 for type TYPE (an INTEGER_TYPE). */
4342 int_fits_type_p (c, type)
4345 if (TREE_UNSIGNED (type))
4346 return (! (TREE_CODE (TYPE_MAX_VALUE (type)) == INTEGER_CST
4347 && INT_CST_LT_UNSIGNED (TYPE_MAX_VALUE (type), c))
4348 && ! (TREE_CODE (TYPE_MIN_VALUE (type)) == INTEGER_CST
4349 && INT_CST_LT_UNSIGNED (c, TYPE_MIN_VALUE (type))));
4351 return (! (TREE_CODE (TYPE_MAX_VALUE (type)) == INTEGER_CST
4352 && INT_CST_LT (TYPE_MAX_VALUE (type), c))
4353 && ! (TREE_CODE (TYPE_MIN_VALUE (type)) == INTEGER_CST
4354 && INT_CST_LT (c, TYPE_MIN_VALUE (type))));
4357 /* Return the innermost context enclosing DECL that is
4358 a FUNCTION_DECL, or zero if none. */
4361 decl_function_context (decl)
4366 if (TREE_CODE (decl) == ERROR_MARK)
4369 if (TREE_CODE (decl) == SAVE_EXPR)
4370 context = SAVE_EXPR_CONTEXT (decl);
4372 context = DECL_CONTEXT (decl);
4374 while (context && TREE_CODE (context) != FUNCTION_DECL)
4376 if (TREE_CODE (context) == RECORD_TYPE
4377 || TREE_CODE (context) == UNION_TYPE
4378 || TREE_CODE (context) == QUAL_UNION_TYPE)
4379 context = TYPE_CONTEXT (context);
4380 else if (TREE_CODE (context) == TYPE_DECL)
4381 context = DECL_CONTEXT (context);
4382 else if (TREE_CODE (context) == BLOCK)
4383 context = BLOCK_SUPERCONTEXT (context);
4385 /* Unhandled CONTEXT !? */
4392 /* Return the innermost context enclosing DECL that is
4393 a RECORD_TYPE, UNION_TYPE or QUAL_UNION_TYPE, or zero if none.
4394 TYPE_DECLs and FUNCTION_DECLs are transparent to this function. */
4397 decl_type_context (decl)
4400 tree context = DECL_CONTEXT (decl);
4404 if (TREE_CODE (context) == RECORD_TYPE
4405 || TREE_CODE (context) == UNION_TYPE
4406 || TREE_CODE (context) == QUAL_UNION_TYPE)
4408 if (TREE_CODE (context) == TYPE_DECL
4409 || TREE_CODE (context) == FUNCTION_DECL)
4410 context = DECL_CONTEXT (context);
4411 else if (TREE_CODE (context) == BLOCK)
4412 context = BLOCK_SUPERCONTEXT (context);
4414 /* Unhandled CONTEXT!? */
4421 print_obstack_statistics (str, o)
4425 struct _obstack_chunk *chunk = o->chunk;
4432 n_alloc += chunk->limit - &chunk->contents[0];
4433 chunk = chunk->prev;
4435 fprintf (stderr, "obstack %s: %d bytes, %d chunks\n",
4436 str, n_alloc, n_chunks);
4439 dump_tree_statistics ()
4442 int total_nodes, total_bytes;
4444 fprintf (stderr, "\n??? tree nodes created\n\n");
4445 #ifdef GATHER_STATISTICS
4446 fprintf (stderr, "Kind Nodes Bytes\n");
4447 fprintf (stderr, "-------------------------------------\n");
4448 total_nodes = total_bytes = 0;
4449 for (i = 0; i < (int) all_kinds; i++)
4451 fprintf (stderr, "%-20s %6d %9d\n", tree_node_kind_names[i],
4452 tree_node_counts[i], tree_node_sizes[i]);
4453 total_nodes += tree_node_counts[i];
4454 total_bytes += tree_node_sizes[i];
4456 fprintf (stderr, "%-20s %9d\n", "identifier names", id_string_size);
4457 fprintf (stderr, "-------------------------------------\n");
4458 fprintf (stderr, "%-20s %6d %9d\n", "Total", total_nodes, total_bytes);
4459 fprintf (stderr, "-------------------------------------\n");
4461 fprintf (stderr, "(No per-node statistics)\n");
4463 print_lang_statistics ();
4466 #define FILE_FUNCTION_PREFIX_LEN 9
4468 #ifndef NO_DOLLAR_IN_LABEL
4469 #define FILE_FUNCTION_FORMAT "_GLOBAL_$D$%s"
4470 #else /* NO_DOLLAR_IN_LABEL */
4471 #ifndef NO_DOT_IN_LABEL
4472 #define FILE_FUNCTION_FORMAT "_GLOBAL_.D.%s"
4473 #else /* NO_DOT_IN_LABEL */
4474 #define FILE_FUNCTION_FORMAT "_GLOBAL__D_%s"
4475 #endif /* NO_DOT_IN_LABEL */
4476 #endif /* NO_DOLLAR_IN_LABEL */
4478 extern char * first_global_object_name;
4480 /* If KIND=='I', return a suitable global initializer (constructor) name.
4481 If KIND=='D', return a suitable global clean-up (destructor) name. */
4484 get_file_function_name (kind)
4490 if (first_global_object_name)
4491 p = first_global_object_name;
4492 else if (main_input_filename)
4493 p = main_input_filename;
4497 buf = (char *) alloca (sizeof (FILE_FUNCTION_FORMAT) + strlen (p));
4499 /* Set up the name of the file-level functions we may need. */
4500 /* Use a global object (which is already required to be unique over
4501 the program) rather than the file name (which imposes extra
4502 constraints). -- Raeburn@MIT.EDU, 10 Jan 1990. */
4503 sprintf (buf, FILE_FUNCTION_FORMAT, p);
4505 /* Don't need to pull weird characters out of global names. */
4506 if (p != first_global_object_name)
4508 for (p = buf+11; *p; p++)
4509 if (! ((*p >= '0' && *p <= '9')
4510 #if 0 /* we always want labels, which are valid C++ identifiers (+ `$') */
4511 #ifndef ASM_IDENTIFY_GCC /* this is required if `.' is invalid -- k. raeburn */
4515 #ifndef NO_DOLLAR_IN_LABEL /* this for `$'; unlikely, but... -- kr */
4518 #ifndef NO_DOT_IN_LABEL /* this for `.'; unlikely, but... */
4521 || (*p >= 'A' && *p <= 'Z')
4522 || (*p >= 'a' && *p <= 'z')))
4526 buf[FILE_FUNCTION_PREFIX_LEN] = kind;
4528 return get_identifier (buf);
4531 /* Expand (the constant part of) a SET_TYPE CONSTRUCTOR node.
4532 The result is placed in BUFFER (which has length BIT_SIZE),
4533 with one bit in each char ('\000' or '\001').
4535 If the constructor is constant, NULL_TREE is returned.
4536 Otherwise, a TREE_LIST of the non-constant elements is emitted. */
4539 get_set_constructor_bits (init, buffer, bit_size)
4546 HOST_WIDE_INT domain_min
4547 = TREE_INT_CST_LOW (TYPE_MIN_VALUE (TYPE_DOMAIN (TREE_TYPE (init))));
4548 tree non_const_bits = NULL_TREE;
4549 for (i = 0; i < bit_size; i++)
4552 for (vals = TREE_OPERAND (init, 1);
4553 vals != NULL_TREE; vals = TREE_CHAIN (vals))
4555 if (TREE_CODE (TREE_VALUE (vals)) != INTEGER_CST
4556 || (TREE_PURPOSE (vals) != NULL_TREE
4557 && TREE_CODE (TREE_PURPOSE (vals)) != INTEGER_CST))
4559 = tree_cons (TREE_PURPOSE (vals), TREE_VALUE (vals), non_const_bits);
4560 else if (TREE_PURPOSE (vals) != NULL_TREE)
4562 /* Set a range of bits to ones. */
4563 HOST_WIDE_INT lo_index
4564 = TREE_INT_CST_LOW (TREE_PURPOSE (vals)) - domain_min;
4565 HOST_WIDE_INT hi_index
4566 = TREE_INT_CST_LOW (TREE_VALUE (vals)) - domain_min;
4567 if (lo_index < 0 || lo_index >= bit_size
4568 || hi_index < 0 || hi_index >= bit_size)
4570 for ( ; lo_index <= hi_index; lo_index++)
4571 buffer[lo_index] = 1;
4575 /* Set a single bit to one. */
4577 = TREE_INT_CST_LOW (TREE_VALUE (vals)) - domain_min;
4578 if (index < 0 || index >= bit_size)
4580 error ("invalid initializer for bit string");
4586 return non_const_bits;
4589 /* Expand (the constant part of) a SET_TYPE CONSTRUCTOR node.
4590 The result is placed in BUFFER (which is an array of bytes).
4591 If the constructor is constant, NULL_TREE is returned.
4592 Otherwise, a TREE_LIST of the non-constant elements is emitted. */
4595 get_set_constructor_bytes (init, buffer, wd_size)
4597 unsigned char *buffer;
4601 tree vals = TREE_OPERAND (init, 1);
4602 int set_word_size = BITS_PER_UNIT;
4603 int bit_size = wd_size * set_word_size;
4605 unsigned char *bytep = buffer;
4606 char *bit_buffer = (char *) alloca(bit_size);
4607 tree non_const_bits = get_set_constructor_bits (init, bit_buffer, bit_size);
4609 for (i = 0; i < wd_size; i++)
4612 for (i = 0; i < bit_size; i++)
4616 if (BYTES_BIG_ENDIAN)
4617 *bytep |= (1 << (set_word_size - 1 - bit_pos));
4619 *bytep |= 1 << bit_pos;
4622 if (bit_pos >= set_word_size)
4623 bit_pos = 0, bytep++;
4625 return non_const_bits;