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. */
54 #ifdef NEED_DECLARATION_FREE
55 extern void free PROTO((void *));
58 #define obstack_chunk_alloc xmalloc
59 #define obstack_chunk_free free
61 /* Tree nodes of permanent duration are allocated in this obstack.
62 They are the identifier nodes, and everything outside of
63 the bodies and parameters of function definitions. */
65 struct obstack permanent_obstack;
67 /* The initial RTL, and all ..._TYPE nodes, in a function
68 are allocated in this obstack. Usually they are freed at the
69 end of the function, but if the function is inline they are saved.
70 For top-level functions, this is maybepermanent_obstack.
71 Separate obstacks are made for nested functions. */
73 struct obstack *function_maybepermanent_obstack;
75 /* This is the function_maybepermanent_obstack for top-level functions. */
77 struct obstack maybepermanent_obstack;
79 /* This is a list of function_maybepermanent_obstacks for top-level inline
80 functions that are compiled in the middle of compiling other functions. */
82 struct simple_obstack_stack *toplev_inline_obstacks;
84 /* This is a list of function_maybepermanent_obstacks for inline functions
85 nested in the current function that were compiled in the middle of
86 compiling other functions. */
88 struct simple_obstack_stack *inline_obstacks;
90 /* The contents of the current function definition are allocated
91 in this obstack, and all are freed at the end of the function.
92 For top-level functions, this is temporary_obstack.
93 Separate obstacks are made for nested functions. */
95 struct obstack *function_obstack;
97 /* This is used for reading initializers of global variables. */
99 struct obstack temporary_obstack;
101 /* The tree nodes of an expression are allocated
102 in this obstack, and all are freed at the end of the expression. */
104 struct obstack momentary_obstack;
106 /* The tree nodes of a declarator are allocated
107 in this obstack, and all are freed when the declarator
110 static struct obstack temp_decl_obstack;
112 /* This points at either permanent_obstack
113 or the current function_maybepermanent_obstack. */
115 struct obstack *saveable_obstack;
117 /* This is same as saveable_obstack during parse and expansion phase;
118 it points to the current function's obstack during optimization.
119 This is the obstack to be used for creating rtl objects. */
121 struct obstack *rtl_obstack;
123 /* This points at either permanent_obstack or the current function_obstack. */
125 struct obstack *current_obstack;
127 /* This points at either permanent_obstack or the current function_obstack
128 or momentary_obstack. */
130 struct obstack *expression_obstack;
132 /* Stack of obstack selections for push_obstacks and pop_obstacks. */
136 struct obstack_stack *next;
137 struct obstack *current;
138 struct obstack *saveable;
139 struct obstack *expression;
143 struct obstack_stack *obstack_stack;
145 /* Obstack for allocating struct obstack_stack entries. */
147 static struct obstack obstack_stack_obstack;
149 /* Addresses of first objects in some obstacks.
150 This is for freeing their entire contents. */
151 char *maybepermanent_firstobj;
152 char *temporary_firstobj;
153 char *momentary_firstobj;
154 char *temp_decl_firstobj;
156 /* This is used to preserve objects (mainly array initializers) that need to
157 live until the end of the current function, but no further. */
158 char *momentary_function_firstobj;
160 /* Nonzero means all ..._TYPE nodes should be allocated permanently. */
162 int all_types_permanent;
164 /* Stack of places to restore the momentary obstack back to. */
166 struct momentary_level
168 /* Pointer back to previous such level. */
169 struct momentary_level *prev;
170 /* First object allocated within this level. */
172 /* Value of expression_obstack saved at entry to this level. */
173 struct obstack *obstack;
176 struct momentary_level *momentary_stack;
178 /* Table indexed by tree code giving a string containing a character
179 classifying the tree code. Possibilities are
180 t, d, s, c, r, <, 1, 2 and e. See tree.def for details. */
182 #define DEFTREECODE(SYM, NAME, TYPE, LENGTH) TYPE,
184 char *standard_tree_code_type[] = {
189 /* Table indexed by tree code giving number of expression
190 operands beyond the fixed part of the node structure.
191 Not used for types or decls. */
193 #define DEFTREECODE(SYM, NAME, TYPE, LENGTH) LENGTH,
195 int standard_tree_code_length[] = {
200 /* Names of tree components.
201 Used for printing out the tree and error messages. */
202 #define DEFTREECODE(SYM, NAME, TYPE, LEN) NAME,
204 char *standard_tree_code_name[] = {
209 /* Table indexed by tree code giving a string containing a character
210 classifying the tree code. Possibilities are
211 t, d, s, c, r, e, <, 1 and 2. See tree.def for details. */
213 char **tree_code_type;
215 /* Table indexed by tree code giving number of expression
216 operands beyond the fixed part of the node structure.
217 Not used for types or decls. */
219 int *tree_code_length;
221 /* Table indexed by tree code giving name of tree code, as a string. */
223 char **tree_code_name;
225 /* Statistics-gathering stuff. */
246 int tree_node_counts[(int)all_kinds];
247 int tree_node_sizes[(int)all_kinds];
248 int id_string_size = 0;
250 char *tree_node_kind_names[] = {
268 /* Hash table for uniquizing IDENTIFIER_NODEs by name. */
270 #define MAX_HASH_TABLE 1009
271 static tree hash_table[MAX_HASH_TABLE]; /* id hash buckets */
273 /* 0 while creating built-in identifiers. */
274 static int do_identifier_warnings;
276 /* Unique id for next decl created. */
277 static int next_decl_uid;
278 /* Unique id for next type created. */
279 static int next_type_uid = 1;
281 /* Here is how primitive or already-canonicalized types' hash
283 #define TYPE_HASH(TYPE) ((HOST_WIDE_INT) (TYPE) & 0777777)
285 extern char *mode_name[];
287 void gcc_obstack_init ();
289 /* Init the principal obstacks. */
294 gcc_obstack_init (&obstack_stack_obstack);
295 gcc_obstack_init (&permanent_obstack);
297 gcc_obstack_init (&temporary_obstack);
298 temporary_firstobj = (char *) obstack_alloc (&temporary_obstack, 0);
299 gcc_obstack_init (&momentary_obstack);
300 momentary_firstobj = (char *) obstack_alloc (&momentary_obstack, 0);
301 momentary_function_firstobj = momentary_firstobj;
302 gcc_obstack_init (&maybepermanent_obstack);
303 maybepermanent_firstobj
304 = (char *) obstack_alloc (&maybepermanent_obstack, 0);
305 gcc_obstack_init (&temp_decl_obstack);
306 temp_decl_firstobj = (char *) obstack_alloc (&temp_decl_obstack, 0);
308 function_obstack = &temporary_obstack;
309 function_maybepermanent_obstack = &maybepermanent_obstack;
310 current_obstack = &permanent_obstack;
311 expression_obstack = &permanent_obstack;
312 rtl_obstack = saveable_obstack = &permanent_obstack;
314 /* Init the hash table of identifiers. */
315 bzero ((char *) hash_table, sizeof hash_table);
319 gcc_obstack_init (obstack)
320 struct obstack *obstack;
322 /* Let particular systems override the size of a chunk. */
323 #ifndef OBSTACK_CHUNK_SIZE
324 #define OBSTACK_CHUNK_SIZE 0
326 /* Let them override the alloc and free routines too. */
327 #ifndef OBSTACK_CHUNK_ALLOC
328 #define OBSTACK_CHUNK_ALLOC xmalloc
330 #ifndef OBSTACK_CHUNK_FREE
331 #define OBSTACK_CHUNK_FREE free
333 _obstack_begin (obstack, OBSTACK_CHUNK_SIZE, 0,
334 (void *(*) ()) OBSTACK_CHUNK_ALLOC,
335 (void (*) ()) OBSTACK_CHUNK_FREE);
338 /* Save all variables describing the current status into the structure *P.
339 This is used before starting a nested function.
341 CONTEXT is the decl_function_context for the function we're about to
342 compile; if it isn't current_function_decl, we have to play some games. */
345 save_tree_status (p, context)
349 p->all_types_permanent = all_types_permanent;
350 p->momentary_stack = momentary_stack;
351 p->maybepermanent_firstobj = maybepermanent_firstobj;
352 p->temporary_firstobj = temporary_firstobj;
353 p->momentary_firstobj = momentary_firstobj;
354 p->momentary_function_firstobj = momentary_function_firstobj;
355 p->function_obstack = function_obstack;
356 p->function_maybepermanent_obstack = function_maybepermanent_obstack;
357 p->current_obstack = current_obstack;
358 p->expression_obstack = expression_obstack;
359 p->saveable_obstack = saveable_obstack;
360 p->rtl_obstack = rtl_obstack;
361 p->inline_obstacks = inline_obstacks;
363 if (context == current_function_decl)
364 /* Objects that need to be saved in this function can be in the nonsaved
365 obstack of the enclosing function since they can't possibly be needed
366 once it has returned. */
367 function_maybepermanent_obstack = function_obstack;
370 /* We're compiling a function which isn't nested in the current
371 function. We need to create a new maybepermanent_obstack for this
372 function, since it can't go onto any of the existing obstacks. */
373 struct simple_obstack_stack **head;
374 struct simple_obstack_stack *current;
376 if (context == NULL_TREE)
377 head = &toplev_inline_obstacks;
380 struct function *f = find_function_data (context);
381 head = &f->inline_obstacks;
384 current = ((struct simple_obstack_stack *)
385 xmalloc (sizeof (struct simple_obstack_stack)));
387 current->obstack = (struct obstack *) xmalloc (sizeof (struct obstack));
388 function_maybepermanent_obstack = current->obstack;
389 gcc_obstack_init (function_maybepermanent_obstack);
391 current->next = *head;
395 maybepermanent_firstobj
396 = (char *) obstack_finish (function_maybepermanent_obstack);
398 function_obstack = (struct obstack *) xmalloc (sizeof (struct obstack));
399 gcc_obstack_init (function_obstack);
401 current_obstack = &permanent_obstack;
402 expression_obstack = &permanent_obstack;
403 rtl_obstack = saveable_obstack = &permanent_obstack;
405 temporary_firstobj = (char *) obstack_alloc (&temporary_obstack, 0);
406 momentary_firstobj = (char *) obstack_finish (&momentary_obstack);
407 momentary_function_firstobj = momentary_firstobj;
410 /* Restore all variables describing the current status from the structure *P.
411 This is used after a nested function. */
414 restore_tree_status (p)
417 all_types_permanent = p->all_types_permanent;
418 momentary_stack = p->momentary_stack;
420 obstack_free (&momentary_obstack, momentary_function_firstobj);
422 /* Free saveable storage used by the function just compiled and not
425 CAUTION: This is in function_obstack of the containing function.
426 So we must be sure that we never allocate from that obstack during
427 the compilation of a nested function if we expect it to survive
428 past the nested function's end. */
429 obstack_free (function_maybepermanent_obstack, maybepermanent_firstobj);
431 obstack_free (function_obstack, 0);
432 free (function_obstack);
434 temporary_firstobj = p->temporary_firstobj;
435 momentary_firstobj = p->momentary_firstobj;
436 momentary_function_firstobj = p->momentary_function_firstobj;
437 maybepermanent_firstobj = p->maybepermanent_firstobj;
438 function_obstack = p->function_obstack;
439 function_maybepermanent_obstack = p->function_maybepermanent_obstack;
440 current_obstack = p->current_obstack;
441 expression_obstack = p->expression_obstack;
442 saveable_obstack = p->saveable_obstack;
443 rtl_obstack = p->rtl_obstack;
444 inline_obstacks = p->inline_obstacks;
447 /* Start allocating on the temporary (per function) obstack.
448 This is done in start_function before parsing the function body,
449 and before each initialization at top level, and to go back
450 to temporary allocation after doing permanent_allocation. */
453 temporary_allocation ()
455 /* Note that function_obstack at top level points to temporary_obstack.
456 But within a nested function context, it is a separate obstack. */
457 current_obstack = function_obstack;
458 expression_obstack = function_obstack;
459 rtl_obstack = saveable_obstack = function_maybepermanent_obstack;
464 /* Start allocating on the permanent obstack but don't
465 free the temporary data. After calling this, call
466 `permanent_allocation' to fully resume permanent allocation status. */
469 end_temporary_allocation ()
471 current_obstack = &permanent_obstack;
472 expression_obstack = &permanent_obstack;
473 rtl_obstack = saveable_obstack = &permanent_obstack;
476 /* Resume allocating on the temporary obstack, undoing
477 effects of `end_temporary_allocation'. */
480 resume_temporary_allocation ()
482 current_obstack = function_obstack;
483 expression_obstack = function_obstack;
484 rtl_obstack = saveable_obstack = function_maybepermanent_obstack;
487 /* While doing temporary allocation, switch to allocating in such a
488 way as to save all nodes if the function is inlined. Call
489 resume_temporary_allocation to go back to ordinary temporary
493 saveable_allocation ()
495 /* Note that function_obstack at top level points to temporary_obstack.
496 But within a nested function context, it is a separate obstack. */
497 expression_obstack = current_obstack = saveable_obstack;
500 /* Switch to current obstack CURRENT and maybepermanent obstack SAVEABLE,
501 recording the previously current obstacks on a stack.
502 This does not free any storage in any obstack. */
505 push_obstacks (current, saveable)
506 struct obstack *current, *saveable;
508 struct obstack_stack *p
509 = (struct obstack_stack *) obstack_alloc (&obstack_stack_obstack,
510 (sizeof (struct obstack_stack)));
512 p->current = current_obstack;
513 p->saveable = saveable_obstack;
514 p->expression = expression_obstack;
515 p->rtl = rtl_obstack;
516 p->next = obstack_stack;
519 current_obstack = current;
520 expression_obstack = current;
521 rtl_obstack = saveable_obstack = saveable;
524 /* Save the current set of obstacks, but don't change them. */
527 push_obstacks_nochange ()
529 struct obstack_stack *p
530 = (struct obstack_stack *) obstack_alloc (&obstack_stack_obstack,
531 (sizeof (struct obstack_stack)));
533 p->current = current_obstack;
534 p->saveable = saveable_obstack;
535 p->expression = expression_obstack;
536 p->rtl = rtl_obstack;
537 p->next = obstack_stack;
541 /* Pop the obstack selection stack. */
546 struct obstack_stack *p = obstack_stack;
547 obstack_stack = p->next;
549 current_obstack = p->current;
550 saveable_obstack = p->saveable;
551 expression_obstack = p->expression;
552 rtl_obstack = p->rtl;
554 obstack_free (&obstack_stack_obstack, p);
557 /* Nonzero if temporary allocation is currently in effect.
558 Zero if currently doing permanent allocation. */
561 allocation_temporary_p ()
563 return current_obstack != &permanent_obstack;
566 /* Go back to allocating on the permanent obstack
567 and free everything in the temporary obstack.
569 FUNCTION_END is true only if we have just finished compiling a function.
570 In that case, we also free preserved initial values on the momentary
574 permanent_allocation (function_end)
577 /* Free up previous temporary obstack data */
578 obstack_free (&temporary_obstack, temporary_firstobj);
581 obstack_free (&momentary_obstack, momentary_function_firstobj);
582 momentary_firstobj = momentary_function_firstobj;
585 obstack_free (&momentary_obstack, momentary_firstobj);
586 obstack_free (function_maybepermanent_obstack, maybepermanent_firstobj);
587 obstack_free (&temp_decl_obstack, temp_decl_firstobj);
589 /* Free up the maybepermanent_obstacks for any of our nested functions
590 which were compiled at a lower level. */
591 while (inline_obstacks)
593 struct simple_obstack_stack *current = inline_obstacks;
594 inline_obstacks = current->next;
595 obstack_free (current->obstack, 0);
596 free (current->obstack);
600 current_obstack = &permanent_obstack;
601 expression_obstack = &permanent_obstack;
602 rtl_obstack = saveable_obstack = &permanent_obstack;
605 /* Save permanently everything on the maybepermanent_obstack. */
610 maybepermanent_firstobj
611 = (char *) obstack_alloc (function_maybepermanent_obstack, 0);
615 preserve_initializer ()
617 struct momentary_level *tem;
621 = (char *) obstack_alloc (&temporary_obstack, 0);
622 maybepermanent_firstobj
623 = (char *) obstack_alloc (function_maybepermanent_obstack, 0);
625 old_momentary = momentary_firstobj;
627 = (char *) obstack_alloc (&momentary_obstack, 0);
628 if (momentary_firstobj != old_momentary)
629 for (tem = momentary_stack; tem; tem = tem->prev)
630 tem->base = momentary_firstobj;
633 /* Start allocating new rtl in current_obstack.
634 Use resume_temporary_allocation
635 to go back to allocating rtl in saveable_obstack. */
638 rtl_in_current_obstack ()
640 rtl_obstack = current_obstack;
643 /* Start allocating rtl from saveable_obstack. Intended to be used after
644 a call to push_obstacks_nochange. */
647 rtl_in_saveable_obstack ()
649 rtl_obstack = saveable_obstack;
652 /* Allocate SIZE bytes in the current obstack
653 and return a pointer to them.
654 In practice the current obstack is always the temporary one. */
660 return (char *) obstack_alloc (current_obstack, size);
663 /* Free the object PTR in the current obstack
664 as well as everything allocated since PTR.
665 In practice the current obstack is always the temporary one. */
671 obstack_free (current_obstack, ptr);
674 /* Allocate SIZE bytes in the permanent obstack
675 and return a pointer to them. */
681 return (char *) obstack_alloc (&permanent_obstack, size);
684 /* Allocate NELEM items of SIZE bytes in the permanent obstack
685 and return a pointer to them. The storage is cleared before
686 returning the value. */
689 perm_calloc (nelem, size)
693 char *rval = (char *) obstack_alloc (&permanent_obstack, nelem * size);
694 bzero (rval, nelem * size);
698 /* Allocate SIZE bytes in the saveable obstack
699 and return a pointer to them. */
705 return (char *) obstack_alloc (saveable_obstack, size);
708 /* Print out which obstack an object is in. */
711 print_obstack_name (object, file, prefix)
716 struct obstack *obstack = NULL;
717 char *obstack_name = NULL;
720 for (p = outer_function_chain; p; p = p->next)
722 if (_obstack_allocated_p (p->function_obstack, object))
724 obstack = p->function_obstack;
725 obstack_name = "containing function obstack";
727 if (_obstack_allocated_p (p->function_maybepermanent_obstack, object))
729 obstack = p->function_maybepermanent_obstack;
730 obstack_name = "containing function maybepermanent obstack";
734 if (_obstack_allocated_p (&obstack_stack_obstack, object))
736 obstack = &obstack_stack_obstack;
737 obstack_name = "obstack_stack_obstack";
739 else if (_obstack_allocated_p (function_obstack, object))
741 obstack = function_obstack;
742 obstack_name = "function obstack";
744 else if (_obstack_allocated_p (&permanent_obstack, object))
746 obstack = &permanent_obstack;
747 obstack_name = "permanent_obstack";
749 else if (_obstack_allocated_p (&momentary_obstack, object))
751 obstack = &momentary_obstack;
752 obstack_name = "momentary_obstack";
754 else if (_obstack_allocated_p (function_maybepermanent_obstack, object))
756 obstack = function_maybepermanent_obstack;
757 obstack_name = "function maybepermanent obstack";
759 else if (_obstack_allocated_p (&temp_decl_obstack, object))
761 obstack = &temp_decl_obstack;
762 obstack_name = "temp_decl_obstack";
765 /* Check to see if the object is in the free area of the obstack. */
768 if (object >= obstack->next_free
769 && object < obstack->chunk_limit)
770 fprintf (file, "%s in free portion of obstack %s",
771 prefix, obstack_name);
773 fprintf (file, "%s allocated from %s", prefix, obstack_name);
776 fprintf (file, "%s not allocated from any obstack", prefix);
780 debug_obstack (object)
783 print_obstack_name (object, stderr, "object");
784 fprintf (stderr, ".\n");
787 /* Return 1 if OBJ is in the permanent obstack.
788 This is slow, and should be used only for debugging.
789 Use TREE_PERMANENT for other purposes. */
792 object_permanent_p (obj)
795 return _obstack_allocated_p (&permanent_obstack, obj);
798 /* Start a level of momentary allocation.
799 In C, each compound statement has its own level
800 and that level is freed at the end of each statement.
801 All expression nodes are allocated in the momentary allocation level. */
806 struct momentary_level *tem
807 = (struct momentary_level *) obstack_alloc (&momentary_obstack,
808 sizeof (struct momentary_level));
809 tem->prev = momentary_stack;
810 tem->base = (char *) obstack_base (&momentary_obstack);
811 tem->obstack = expression_obstack;
812 momentary_stack = tem;
813 expression_obstack = &momentary_obstack;
816 /* Set things up so the next clear_momentary will only clear memory
817 past our present position in momentary_obstack. */
820 preserve_momentary ()
822 momentary_stack->base = (char *) obstack_base (&momentary_obstack);
825 /* Free all the storage in the current momentary-allocation level.
826 In C, this happens at the end of each statement. */
831 obstack_free (&momentary_obstack, momentary_stack->base);
834 /* Discard a level of momentary allocation.
835 In C, this happens at the end of each compound statement.
836 Restore the status of expression node allocation
837 that was in effect before this level was created. */
842 struct momentary_level *tem = momentary_stack;
843 momentary_stack = tem->prev;
844 expression_obstack = tem->obstack;
845 /* We can't free TEM from the momentary_obstack, because there might
846 be objects above it which have been saved. We can free back to the
847 stack of the level we are popping off though. */
848 obstack_free (&momentary_obstack, tem->base);
851 /* Pop back to the previous level of momentary allocation,
852 but don't free any momentary data just yet. */
855 pop_momentary_nofree ()
857 struct momentary_level *tem = momentary_stack;
858 momentary_stack = tem->prev;
859 expression_obstack = tem->obstack;
862 /* Call when starting to parse a declaration:
863 make expressions in the declaration last the length of the function.
864 Returns an argument that should be passed to resume_momentary later. */
869 register int tem = expression_obstack == &momentary_obstack;
870 expression_obstack = saveable_obstack;
874 /* Call when finished parsing a declaration:
875 restore the treatment of node-allocation that was
876 in effect before the suspension.
877 YES should be the value previously returned by suspend_momentary. */
880 resume_momentary (yes)
884 expression_obstack = &momentary_obstack;
887 /* Init the tables indexed by tree code.
888 Note that languages can add to these tables to define their own codes. */
893 tree_code_type = (char **) xmalloc (sizeof (standard_tree_code_type));
894 tree_code_length = (int *) xmalloc (sizeof (standard_tree_code_length));
895 tree_code_name = (char **) xmalloc (sizeof (standard_tree_code_name));
896 bcopy ((char *) standard_tree_code_type, (char *) tree_code_type,
897 sizeof (standard_tree_code_type));
898 bcopy ((char *) standard_tree_code_length, (char *) tree_code_length,
899 sizeof (standard_tree_code_length));
900 bcopy ((char *) standard_tree_code_name, (char *) tree_code_name,
901 sizeof (standard_tree_code_name));
904 /* Return a newly allocated node of code CODE.
905 Initialize the node's unique id and its TREE_PERMANENT flag.
906 For decl and type nodes, some other fields are initialized.
907 The rest of the node is initialized to zero.
909 Achoo! I got a code in the node. */
916 register int type = TREE_CODE_CLASS (code);
918 register struct obstack *obstack = current_obstack;
920 register tree_node_kind kind;
924 case 'd': /* A decl node */
925 #ifdef GATHER_STATISTICS
928 length = sizeof (struct tree_decl);
929 /* All decls in an inline function need to be saved. */
930 if (obstack != &permanent_obstack)
931 obstack = saveable_obstack;
933 /* PARM_DECLs go on the context of the parent. If this is a nested
934 function, then we must allocate the PARM_DECL on the parent's
935 obstack, so that they will live to the end of the parent's
936 closing brace. This is necessary in case we try to inline the
937 function into its parent.
939 PARM_DECLs of top-level functions do not have this problem. However,
940 we allocate them where we put the FUNCTION_DECL for languages such as
941 Ada that need to consult some flags in the PARM_DECLs of the function
944 See comment in restore_tree_status for why we can't put this
945 in function_obstack. */
946 if (code == PARM_DECL && obstack != &permanent_obstack)
949 if (current_function_decl)
950 context = decl_function_context (current_function_decl);
954 = find_function_data (context)->function_maybepermanent_obstack;
958 case 't': /* a type node */
959 #ifdef GATHER_STATISTICS
962 length = sizeof (struct tree_type);
963 /* All data types are put where we can preserve them if nec. */
964 if (obstack != &permanent_obstack)
965 obstack = all_types_permanent ? &permanent_obstack : saveable_obstack;
968 case 'b': /* a lexical block */
969 #ifdef GATHER_STATISTICS
972 length = sizeof (struct tree_block);
973 /* All BLOCK nodes are put where we can preserve them if nec. */
974 if (obstack != &permanent_obstack)
975 obstack = saveable_obstack;
978 case 's': /* an expression with side effects */
979 #ifdef GATHER_STATISTICS
983 case 'r': /* a reference */
984 #ifdef GATHER_STATISTICS
988 case 'e': /* an expression */
989 case '<': /* a comparison expression */
990 case '1': /* a unary arithmetic expression */
991 case '2': /* a binary arithmetic expression */
992 #ifdef GATHER_STATISTICS
996 obstack = expression_obstack;
997 /* All BIND_EXPR nodes are put where we can preserve them if nec. */
998 if (code == BIND_EXPR && obstack != &permanent_obstack)
999 obstack = saveable_obstack;
1000 length = sizeof (struct tree_exp)
1001 + (tree_code_length[(int) code] - 1) * sizeof (char *);
1004 case 'c': /* a constant */
1005 #ifdef GATHER_STATISTICS
1008 obstack = expression_obstack;
1010 /* We can't use tree_code_length for INTEGER_CST, since the number of
1011 words is machine-dependent due to varying length of HOST_WIDE_INT,
1012 which might be wider than a pointer (e.g., long long). Similarly
1013 for REAL_CST, since the number of words is machine-dependent due
1014 to varying size and alignment of `double'. */
1016 if (code == INTEGER_CST)
1017 length = sizeof (struct tree_int_cst);
1018 else if (code == REAL_CST)
1019 length = sizeof (struct tree_real_cst);
1021 length = sizeof (struct tree_common)
1022 + tree_code_length[(int) code] * sizeof (char *);
1025 case 'x': /* something random, like an identifier. */
1026 #ifdef GATHER_STATISTICS
1027 if (code == IDENTIFIER_NODE)
1029 else if (code == OP_IDENTIFIER)
1031 else if (code == TREE_VEC)
1036 length = sizeof (struct tree_common)
1037 + tree_code_length[(int) code] * sizeof (char *);
1038 /* Identifier nodes are always permanent since they are
1039 unique in a compiler run. */
1040 if (code == IDENTIFIER_NODE) obstack = &permanent_obstack;
1047 t = (tree) obstack_alloc (obstack, length);
1049 #ifdef GATHER_STATISTICS
1050 tree_node_counts[(int)kind]++;
1051 tree_node_sizes[(int)kind] += length;
1054 /* Clear a word at a time. */
1055 for (i = (length / sizeof (int)) - 1; i >= 0; i--)
1057 /* Clear any extra bytes. */
1058 for (i = length / sizeof (int) * sizeof (int); i < length; i++)
1059 ((char *) t)[i] = 0;
1061 TREE_SET_CODE (t, code);
1062 if (obstack == &permanent_obstack)
1063 TREE_PERMANENT (t) = 1;
1068 TREE_SIDE_EFFECTS (t) = 1;
1069 TREE_TYPE (t) = void_type_node;
1073 if (code != FUNCTION_DECL)
1075 DECL_IN_SYSTEM_HEADER (t)
1076 = in_system_header && (obstack == &permanent_obstack);
1077 DECL_SOURCE_LINE (t) = lineno;
1078 DECL_SOURCE_FILE (t) = (input_filename) ? input_filename : "<built-in>";
1079 DECL_UID (t) = next_decl_uid++;
1083 TYPE_UID (t) = next_type_uid++;
1085 TYPE_MAIN_VARIANT (t) = t;
1086 TYPE_OBSTACK (t) = obstack;
1087 TYPE_ATTRIBUTES (t) = NULL_TREE;
1088 #ifdef SET_DEFAULT_TYPE_ATTRIBUTES
1089 SET_DEFAULT_TYPE_ATTRIBUTES (t);
1094 TREE_CONSTANT (t) = 1;
1101 /* Return a new node with the same contents as NODE
1102 except that its TREE_CHAIN is zero and it has a fresh uid. */
1109 register enum tree_code code = TREE_CODE (node);
1110 register int length;
1113 switch (TREE_CODE_CLASS (code))
1115 case 'd': /* A decl node */
1116 length = sizeof (struct tree_decl);
1119 case 't': /* a type node */
1120 length = sizeof (struct tree_type);
1123 case 'b': /* a lexical block node */
1124 length = sizeof (struct tree_block);
1127 case 'r': /* a reference */
1128 case 'e': /* an expression */
1129 case 's': /* an expression with side effects */
1130 case '<': /* a comparison expression */
1131 case '1': /* a unary arithmetic expression */
1132 case '2': /* a binary arithmetic expression */
1133 length = sizeof (struct tree_exp)
1134 + (tree_code_length[(int) code] - 1) * sizeof (char *);
1137 case 'c': /* a constant */
1138 /* We can't use tree_code_length for INTEGER_CST, since the number of
1139 words is machine-dependent due to varying length of HOST_WIDE_INT,
1140 which might be wider than a pointer (e.g., long long). Similarly
1141 for REAL_CST, since the number of words is machine-dependent due
1142 to varying size and alignment of `double'. */
1143 if (code == INTEGER_CST)
1144 length = sizeof (struct tree_int_cst);
1145 else if (code == REAL_CST)
1146 length = sizeof (struct tree_real_cst);
1148 length = (sizeof (struct tree_common)
1149 + tree_code_length[(int) code] * sizeof (char *));
1152 case 'x': /* something random, like an identifier. */
1153 length = sizeof (struct tree_common)
1154 + tree_code_length[(int) code] * sizeof (char *);
1155 if (code == TREE_VEC)
1156 length += (TREE_VEC_LENGTH (node) - 1) * sizeof (char *);
1159 t = (tree) obstack_alloc (current_obstack, length);
1161 for (i = (length / sizeof (int)) - 1; i >= 0; i--)
1162 ((int *) t)[i] = ((int *) node)[i];
1163 /* Clear any extra bytes. */
1164 for (i = length / sizeof (int) * sizeof (int); i < length; i++)
1165 ((char *) t)[i] = ((char *) node)[i];
1168 TREE_ASM_WRITTEN (t) = 0;
1170 if (TREE_CODE_CLASS (code) == 'd')
1171 DECL_UID (t) = next_decl_uid++;
1172 else if (TREE_CODE_CLASS (code) == 't')
1174 TYPE_UID (t) = next_type_uid++;
1175 TYPE_OBSTACK (t) = current_obstack;
1177 /* The following is so that the debug code for
1178 the copy is different from the original type.
1179 The two statements usually duplicate each other
1180 (because they clear fields of the same union),
1181 but the optimizer should catch that. */
1182 TYPE_SYMTAB_POINTER (t) = 0;
1183 TYPE_SYMTAB_ADDRESS (t) = 0;
1186 TREE_PERMANENT (t) = (current_obstack == &permanent_obstack);
1191 /* Return a copy of a chain of nodes, chained through the TREE_CHAIN field.
1192 For example, this can copy a list made of TREE_LIST nodes. */
1199 register tree prev, next;
1204 head = prev = copy_node (list);
1205 next = TREE_CHAIN (list);
1208 TREE_CHAIN (prev) = copy_node (next);
1209 prev = TREE_CHAIN (prev);
1210 next = TREE_CHAIN (next);
1217 /* Return an IDENTIFIER_NODE whose name is TEXT (a null-terminated string).
1218 If an identifier with that name has previously been referred to,
1219 the same node is returned this time. */
1222 get_identifier (text)
1223 register char *text;
1228 register int len, hash_len;
1230 /* Compute length of text in len. */
1231 for (len = 0; text[len]; len++);
1233 /* Decide how much of that length to hash on */
1235 if (warn_id_clash && len > id_clash_len)
1236 hash_len = id_clash_len;
1238 /* Compute hash code */
1239 hi = hash_len * 613 + (unsigned) text[0];
1240 for (i = 1; i < hash_len; i += 2)
1241 hi = ((hi * 613) + (unsigned) (text[i]));
1243 hi &= (1 << HASHBITS) - 1;
1244 hi %= MAX_HASH_TABLE;
1246 /* Search table for identifier */
1247 for (idp = hash_table[hi]; idp; idp = TREE_CHAIN (idp))
1248 if (IDENTIFIER_LENGTH (idp) == len
1249 && IDENTIFIER_POINTER (idp)[0] == text[0]
1250 && !bcmp (IDENTIFIER_POINTER (idp), text, len))
1251 return idp; /* <-- return if found */
1253 /* Not found; optionally warn about a similar identifier */
1254 if (warn_id_clash && do_identifier_warnings && len >= id_clash_len)
1255 for (idp = hash_table[hi]; idp; idp = TREE_CHAIN (idp))
1256 if (!strncmp (IDENTIFIER_POINTER (idp), text, id_clash_len))
1258 warning ("`%s' and `%s' identical in first %d characters",
1259 IDENTIFIER_POINTER (idp), text, id_clash_len);
1263 if (tree_code_length[(int) IDENTIFIER_NODE] < 0)
1264 abort (); /* set_identifier_size hasn't been called. */
1266 /* Not found, create one, add to chain */
1267 idp = make_node (IDENTIFIER_NODE);
1268 IDENTIFIER_LENGTH (idp) = len;
1269 #ifdef GATHER_STATISTICS
1270 id_string_size += len;
1273 IDENTIFIER_POINTER (idp) = obstack_copy0 (&permanent_obstack, text, len);
1275 TREE_CHAIN (idp) = hash_table[hi];
1276 hash_table[hi] = idp;
1277 return idp; /* <-- return if created */
1280 /* If an identifier with the name TEXT (a null-terminated string) has
1281 previously been referred to, return that node; otherwise return
1285 maybe_get_identifier (text)
1286 register char *text;
1291 register int len, hash_len;
1293 /* Compute length of text in len. */
1294 for (len = 0; text[len]; len++);
1296 /* Decide how much of that length to hash on */
1298 if (warn_id_clash && len > id_clash_len)
1299 hash_len = id_clash_len;
1301 /* Compute hash code */
1302 hi = hash_len * 613 + (unsigned) text[0];
1303 for (i = 1; i < hash_len; i += 2)
1304 hi = ((hi * 613) + (unsigned) (text[i]));
1306 hi &= (1 << HASHBITS) - 1;
1307 hi %= MAX_HASH_TABLE;
1309 /* Search table for identifier */
1310 for (idp = hash_table[hi]; idp; idp = TREE_CHAIN (idp))
1311 if (IDENTIFIER_LENGTH (idp) == len
1312 && IDENTIFIER_POINTER (idp)[0] == text[0]
1313 && !bcmp (IDENTIFIER_POINTER (idp), text, len))
1314 return idp; /* <-- return if found */
1319 /* Enable warnings on similar identifiers (if requested).
1320 Done after the built-in identifiers are created. */
1323 start_identifier_warnings ()
1325 do_identifier_warnings = 1;
1328 /* Record the size of an identifier node for the language in use.
1329 SIZE is the total size in bytes.
1330 This is called by the language-specific files. This must be
1331 called before allocating any identifiers. */
1334 set_identifier_size (size)
1337 tree_code_length[(int) IDENTIFIER_NODE]
1338 = (size - sizeof (struct tree_common)) / sizeof (tree);
1341 /* Return a newly constructed INTEGER_CST node whose constant value
1342 is specified by the two ints LOW and HI.
1343 The TREE_TYPE is set to `int'.
1345 This function should be used via the `build_int_2' macro. */
1348 build_int_2_wide (low, hi)
1349 HOST_WIDE_INT low, hi;
1351 register tree t = make_node (INTEGER_CST);
1352 TREE_INT_CST_LOW (t) = low;
1353 TREE_INT_CST_HIGH (t) = hi;
1354 TREE_TYPE (t) = integer_type_node;
1358 /* Return a new REAL_CST node whose type is TYPE and value is D. */
1361 build_real (type, d)
1368 /* Check for valid float value for this type on this target machine;
1369 if not, can print error message and store a valid value in D. */
1370 #ifdef CHECK_FLOAT_VALUE
1371 CHECK_FLOAT_VALUE (TYPE_MODE (type), d, overflow);
1374 v = make_node (REAL_CST);
1375 TREE_TYPE (v) = type;
1376 TREE_REAL_CST (v) = d;
1377 TREE_OVERFLOW (v) = TREE_CONSTANT_OVERFLOW (v) = overflow;
1381 /* Return a new REAL_CST node whose type is TYPE
1382 and whose value is the integer value of the INTEGER_CST node I. */
1384 #if !defined (REAL_IS_NOT_DOUBLE) || defined (REAL_ARITHMETIC)
1387 real_value_from_int_cst (type, i)
1392 /* Some 386 compilers mishandle unsigned int to float conversions,
1393 so introduce a temporary variable E to avoid those bugs. */
1395 #ifdef REAL_ARITHMETIC
1396 if (! TREE_UNSIGNED (TREE_TYPE (i)))
1397 REAL_VALUE_FROM_INT (d, TREE_INT_CST_LOW (i), TREE_INT_CST_HIGH (i),
1400 REAL_VALUE_FROM_UNSIGNED_INT (d, TREE_INT_CST_LOW (i),
1401 TREE_INT_CST_HIGH (i), TYPE_MODE (type));
1402 #else /* not REAL_ARITHMETIC */
1403 if (TREE_INT_CST_HIGH (i) < 0 && ! TREE_UNSIGNED (TREE_TYPE (i)))
1405 d = (double) (~ TREE_INT_CST_HIGH (i));
1406 e = ((double) ((HOST_WIDE_INT) 1 << (HOST_BITS_PER_WIDE_INT / 2))
1407 * (double) ((HOST_WIDE_INT) 1 << (HOST_BITS_PER_WIDE_INT / 2)));
1409 e = (double) (unsigned HOST_WIDE_INT) (~ TREE_INT_CST_LOW (i));
1415 d = (double) (unsigned HOST_WIDE_INT) TREE_INT_CST_HIGH (i);
1416 e = ((double) ((HOST_WIDE_INT) 1 << (HOST_BITS_PER_WIDE_INT / 2))
1417 * (double) ((HOST_WIDE_INT) 1 << (HOST_BITS_PER_WIDE_INT / 2)));
1419 e = (double) (unsigned HOST_WIDE_INT) TREE_INT_CST_LOW (i);
1422 #endif /* not REAL_ARITHMETIC */
1426 /* This function can't be implemented if we can't do arithmetic
1427 on the float representation. */
1430 build_real_from_int_cst (type, i)
1435 int overflow = TREE_OVERFLOW (i);
1437 jmp_buf float_error;
1439 v = make_node (REAL_CST);
1440 TREE_TYPE (v) = type;
1442 if (setjmp (float_error))
1449 set_float_handler (float_error);
1451 #ifdef REAL_ARITHMETIC
1452 d = real_value_from_int_cst (type, i);
1454 d = REAL_VALUE_TRUNCATE (TYPE_MODE (type),
1455 real_value_from_int_cst (type, i));
1458 /* Check for valid float value for this type on this target machine. */
1461 set_float_handler (NULL_PTR);
1463 #ifdef CHECK_FLOAT_VALUE
1464 CHECK_FLOAT_VALUE (TYPE_MODE (type), d, overflow);
1467 TREE_REAL_CST (v) = d;
1468 TREE_OVERFLOW (v) = TREE_CONSTANT_OVERFLOW (v) = overflow;
1472 #endif /* not REAL_IS_NOT_DOUBLE, or REAL_ARITHMETIC */
1474 /* Return a newly constructed STRING_CST node whose value is
1475 the LEN characters at STR.
1476 The TREE_TYPE is not initialized. */
1479 build_string (len, str)
1483 /* Put the string in saveable_obstack since it will be placed in the RTL
1484 for an "asm" statement and will also be kept around a while if
1485 deferring constant output in varasm.c. */
1487 register tree s = make_node (STRING_CST);
1488 TREE_STRING_LENGTH (s) = len;
1489 TREE_STRING_POINTER (s) = obstack_copy0 (saveable_obstack, str, len);
1493 /* Return a newly constructed COMPLEX_CST node whose value is
1494 specified by the real and imaginary parts REAL and IMAG.
1495 Both REAL and IMAG should be constant nodes. TYPE, if specified,
1496 will be the type of the COMPLEX_CST; otherwise a new type will be made. */
1499 build_complex (type, real, imag)
1503 register tree t = make_node (COMPLEX_CST);
1505 TREE_REALPART (t) = real;
1506 TREE_IMAGPART (t) = imag;
1507 TREE_TYPE (t) = type ? type : build_complex_type (TREE_TYPE (real));
1508 TREE_OVERFLOW (t) = TREE_OVERFLOW (real) | TREE_OVERFLOW (imag);
1509 TREE_CONSTANT_OVERFLOW (t)
1510 = TREE_CONSTANT_OVERFLOW (real) | TREE_CONSTANT_OVERFLOW (imag);
1514 /* Build a newly constructed TREE_VEC node of length LEN. */
1521 register int length = (len-1) * sizeof (tree) + sizeof (struct tree_vec);
1522 register struct obstack *obstack = current_obstack;
1525 #ifdef GATHER_STATISTICS
1526 tree_node_counts[(int)vec_kind]++;
1527 tree_node_sizes[(int)vec_kind] += length;
1530 t = (tree) obstack_alloc (obstack, length);
1532 for (i = (length / sizeof (int)) - 1; i >= 0; i--)
1535 TREE_SET_CODE (t, TREE_VEC);
1536 TREE_VEC_LENGTH (t) = len;
1537 if (obstack == &permanent_obstack)
1538 TREE_PERMANENT (t) = 1;
1543 /* Return 1 if EXPR is the integer constant zero or a complex constant
1547 integer_zerop (expr)
1552 return ((TREE_CODE (expr) == INTEGER_CST
1553 && ! TREE_CONSTANT_OVERFLOW (expr)
1554 && TREE_INT_CST_LOW (expr) == 0
1555 && TREE_INT_CST_HIGH (expr) == 0)
1556 || (TREE_CODE (expr) == COMPLEX_CST
1557 && integer_zerop (TREE_REALPART (expr))
1558 && integer_zerop (TREE_IMAGPART (expr))));
1561 /* Return 1 if EXPR is the integer constant one or the corresponding
1562 complex constant. */
1570 return ((TREE_CODE (expr) == INTEGER_CST
1571 && ! TREE_CONSTANT_OVERFLOW (expr)
1572 && TREE_INT_CST_LOW (expr) == 1
1573 && TREE_INT_CST_HIGH (expr) == 0)
1574 || (TREE_CODE (expr) == COMPLEX_CST
1575 && integer_onep (TREE_REALPART (expr))
1576 && integer_zerop (TREE_IMAGPART (expr))));
1579 /* Return 1 if EXPR is an integer containing all 1's in as much precision as
1580 it contains. Likewise for the corresponding complex constant. */
1583 integer_all_onesp (expr)
1591 if (TREE_CODE (expr) == COMPLEX_CST
1592 && integer_all_onesp (TREE_REALPART (expr))
1593 && integer_zerop (TREE_IMAGPART (expr)))
1596 else if (TREE_CODE (expr) != INTEGER_CST
1597 || TREE_CONSTANT_OVERFLOW (expr))
1600 uns = TREE_UNSIGNED (TREE_TYPE (expr));
1602 return TREE_INT_CST_LOW (expr) == -1 && TREE_INT_CST_HIGH (expr) == -1;
1604 /* Note that using TYPE_PRECISION here is wrong. We care about the
1605 actual bits, not the (arbitrary) range of the type. */
1606 prec = GET_MODE_BITSIZE (TYPE_MODE (TREE_TYPE (expr)));
1607 if (prec >= HOST_BITS_PER_WIDE_INT)
1609 int high_value, shift_amount;
1611 shift_amount = prec - HOST_BITS_PER_WIDE_INT;
1613 if (shift_amount > HOST_BITS_PER_WIDE_INT)
1614 /* Can not handle precisions greater than twice the host int size. */
1616 else if (shift_amount == HOST_BITS_PER_WIDE_INT)
1617 /* Shifting by the host word size is undefined according to the ANSI
1618 standard, so we must handle this as a special case. */
1621 high_value = ((HOST_WIDE_INT) 1 << shift_amount) - 1;
1623 return TREE_INT_CST_LOW (expr) == -1
1624 && TREE_INT_CST_HIGH (expr) == high_value;
1627 return TREE_INT_CST_LOW (expr) == ((HOST_WIDE_INT) 1 << prec) - 1;
1630 /* Return 1 if EXPR is an integer constant that is a power of 2 (i.e., has only
1634 integer_pow2p (expr)
1638 HOST_WIDE_INT high, low;
1642 if (TREE_CODE (expr) == COMPLEX_CST
1643 && integer_pow2p (TREE_REALPART (expr))
1644 && integer_zerop (TREE_IMAGPART (expr)))
1647 if (TREE_CODE (expr) != INTEGER_CST || TREE_CONSTANT_OVERFLOW (expr))
1650 prec = (TREE_CODE (TREE_TYPE (expr)) == POINTER_TYPE
1651 ? POINTER_SIZE : TYPE_PRECISION (TREE_TYPE (expr)));
1652 high = TREE_INT_CST_HIGH (expr);
1653 low = TREE_INT_CST_LOW (expr);
1655 /* First clear all bits that are beyond the type's precision in case
1656 we've been sign extended. */
1658 if (prec == 2 * HOST_BITS_PER_WIDE_INT)
1660 else if (prec > HOST_BITS_PER_WIDE_INT)
1661 high &= ~((HOST_WIDE_INT) (-1) << (prec - HOST_BITS_PER_WIDE_INT));
1665 if (prec < HOST_BITS_PER_WIDE_INT)
1666 low &= ~((HOST_WIDE_INT) (-1) << prec);
1669 if (high == 0 && low == 0)
1672 return ((high == 0 && (low & (low - 1)) == 0)
1673 || (low == 0 && (high & (high - 1)) == 0));
1676 /* Return the power of two represented by a tree node known to be a
1684 HOST_WIDE_INT high, low;
1688 if (TREE_CODE (expr) == COMPLEX_CST)
1689 return tree_log2 (TREE_REALPART (expr));
1691 prec = (TREE_CODE (TREE_TYPE (expr)) == POINTER_TYPE
1692 ? POINTER_SIZE : TYPE_PRECISION (TREE_TYPE (expr)));
1694 high = TREE_INT_CST_HIGH (expr);
1695 low = TREE_INT_CST_LOW (expr);
1697 /* First clear all bits that are beyond the type's precision in case
1698 we've been sign extended. */
1700 if (prec == 2 * HOST_BITS_PER_WIDE_INT)
1702 else if (prec > HOST_BITS_PER_WIDE_INT)
1703 high &= ~((HOST_WIDE_INT) (-1) << (prec - HOST_BITS_PER_WIDE_INT));
1707 if (prec < HOST_BITS_PER_WIDE_INT)
1708 low &= ~((HOST_WIDE_INT) (-1) << prec);
1711 return (high != 0 ? HOST_BITS_PER_WIDE_INT + exact_log2 (high)
1712 : exact_log2 (low));
1715 /* Return 1 if EXPR is the real constant zero. */
1723 return ((TREE_CODE (expr) == REAL_CST
1724 && ! TREE_CONSTANT_OVERFLOW (expr)
1725 && REAL_VALUES_EQUAL (TREE_REAL_CST (expr), dconst0))
1726 || (TREE_CODE (expr) == COMPLEX_CST
1727 && real_zerop (TREE_REALPART (expr))
1728 && real_zerop (TREE_IMAGPART (expr))));
1731 /* Return 1 if EXPR is the real constant one in real or complex form. */
1739 return ((TREE_CODE (expr) == REAL_CST
1740 && ! TREE_CONSTANT_OVERFLOW (expr)
1741 && REAL_VALUES_EQUAL (TREE_REAL_CST (expr), dconst1))
1742 || (TREE_CODE (expr) == COMPLEX_CST
1743 && real_onep (TREE_REALPART (expr))
1744 && real_zerop (TREE_IMAGPART (expr))));
1747 /* Return 1 if EXPR is the real constant two. */
1755 return ((TREE_CODE (expr) == REAL_CST
1756 && ! TREE_CONSTANT_OVERFLOW (expr)
1757 && REAL_VALUES_EQUAL (TREE_REAL_CST (expr), dconst2))
1758 || (TREE_CODE (expr) == COMPLEX_CST
1759 && real_twop (TREE_REALPART (expr))
1760 && real_zerop (TREE_IMAGPART (expr))));
1763 /* Nonzero if EXP is a constant or a cast of a constant. */
1766 really_constant_p (exp)
1769 /* This is not quite the same as STRIP_NOPS. It does more. */
1770 while (TREE_CODE (exp) == NOP_EXPR
1771 || TREE_CODE (exp) == CONVERT_EXPR
1772 || TREE_CODE (exp) == NON_LVALUE_EXPR)
1773 exp = TREE_OPERAND (exp, 0);
1774 return TREE_CONSTANT (exp);
1777 /* Return first list element whose TREE_VALUE is ELEM.
1778 Return 0 if ELEM is not in LIST. */
1781 value_member (elem, list)
1786 if (elem == TREE_VALUE (list))
1788 list = TREE_CHAIN (list);
1793 /* Return first list element whose TREE_PURPOSE is ELEM.
1794 Return 0 if ELEM is not in LIST. */
1797 purpose_member (elem, list)
1802 if (elem == TREE_PURPOSE (list))
1804 list = TREE_CHAIN (list);
1809 /* Return first list element whose BINFO_TYPE is ELEM.
1810 Return 0 if ELEM is not in LIST. */
1813 binfo_member (elem, list)
1818 if (elem == BINFO_TYPE (list))
1820 list = TREE_CHAIN (list);
1825 /* Return nonzero if ELEM is part of the chain CHAIN. */
1828 chain_member (elem, chain)
1835 chain = TREE_CHAIN (chain);
1841 /* Return nonzero if ELEM is equal to TREE_VALUE (CHAIN) for any piece of
1843 /* ??? This function was added for machine specific attributes but is no
1844 longer used. It could be deleted if we could confirm all front ends
1848 chain_member_value (elem, chain)
1853 if (elem == TREE_VALUE (chain))
1855 chain = TREE_CHAIN (chain);
1861 /* Return nonzero if ELEM is equal to TREE_PURPOSE (CHAIN)
1862 for any piece of chain CHAIN. */
1863 /* ??? This function was added for machine specific attributes but is no
1864 longer used. It could be deleted if we could confirm all front ends
1868 chain_member_purpose (elem, chain)
1873 if (elem == TREE_PURPOSE (chain))
1875 chain = TREE_CHAIN (chain);
1881 /* Return the length of a chain of nodes chained through TREE_CHAIN.
1882 We expect a null pointer to mark the end of the chain.
1883 This is the Lisp primitive `length'. */
1890 register int len = 0;
1892 for (tail = t; tail; tail = TREE_CHAIN (tail))
1898 /* Concatenate two chains of nodes (chained through TREE_CHAIN)
1899 by modifying the last node in chain 1 to point to chain 2.
1900 This is the Lisp primitive `nconc'. */
1912 for (t1 = op1; TREE_CHAIN (t1); t1 = TREE_CHAIN (t1))
1914 TREE_CHAIN (t1) = op2;
1915 for (t2 = op2; t2; t2 = TREE_CHAIN (t2))
1917 abort (); /* Circularity created. */
1923 /* Return the last node in a chain of nodes (chained through TREE_CHAIN). */
1927 register tree chain;
1931 while (next = TREE_CHAIN (chain))
1936 /* Reverse the order of elements in the chain T,
1937 and return the new head of the chain (old last element). */
1943 register tree prev = 0, decl, next;
1944 for (decl = t; decl; decl = next)
1946 next = TREE_CHAIN (decl);
1947 TREE_CHAIN (decl) = prev;
1953 /* Given a chain CHAIN of tree nodes,
1954 construct and return a list of those nodes. */
1960 tree result = NULL_TREE;
1961 tree in_tail = chain;
1962 tree out_tail = NULL_TREE;
1966 tree next = tree_cons (NULL_TREE, in_tail, NULL_TREE);
1968 TREE_CHAIN (out_tail) = next;
1972 in_tail = TREE_CHAIN (in_tail);
1978 /* Return a newly created TREE_LIST node whose
1979 purpose and value fields are PARM and VALUE. */
1982 build_tree_list (parm, value)
1985 register tree t = make_node (TREE_LIST);
1986 TREE_PURPOSE (t) = parm;
1987 TREE_VALUE (t) = value;
1991 /* Similar, but build on the temp_decl_obstack. */
1994 build_decl_list (parm, value)
1998 register struct obstack *ambient_obstack = current_obstack;
1999 current_obstack = &temp_decl_obstack;
2000 node = build_tree_list (parm, value);
2001 current_obstack = ambient_obstack;
2005 /* Return a newly created TREE_LIST node whose
2006 purpose and value fields are PARM and VALUE
2007 and whose TREE_CHAIN is CHAIN. */
2010 tree_cons (purpose, value, chain)
2011 tree purpose, value, chain;
2014 register tree node = make_node (TREE_LIST);
2017 register tree node = (tree) obstack_alloc (current_obstack, sizeof (struct tree_list));
2018 #ifdef GATHER_STATISTICS
2019 tree_node_counts[(int)x_kind]++;
2020 tree_node_sizes[(int)x_kind] += sizeof (struct tree_list);
2023 for (i = (sizeof (struct tree_common) / sizeof (int)) - 1; i >= 0; i--)
2024 ((int *) node)[i] = 0;
2026 TREE_SET_CODE (node, TREE_LIST);
2027 if (current_obstack == &permanent_obstack)
2028 TREE_PERMANENT (node) = 1;
2031 TREE_CHAIN (node) = chain;
2032 TREE_PURPOSE (node) = purpose;
2033 TREE_VALUE (node) = value;
2037 /* Similar, but build on the temp_decl_obstack. */
2040 decl_tree_cons (purpose, value, chain)
2041 tree purpose, value, chain;
2044 register struct obstack *ambient_obstack = current_obstack;
2045 current_obstack = &temp_decl_obstack;
2046 node = tree_cons (purpose, value, chain);
2047 current_obstack = ambient_obstack;
2051 /* Same as `tree_cons' but make a permanent object. */
2054 perm_tree_cons (purpose, value, chain)
2055 tree purpose, value, chain;
2058 register struct obstack *ambient_obstack = current_obstack;
2059 current_obstack = &permanent_obstack;
2061 node = tree_cons (purpose, value, chain);
2062 current_obstack = ambient_obstack;
2066 /* Same as `tree_cons', but make this node temporary, regardless. */
2069 temp_tree_cons (purpose, value, chain)
2070 tree purpose, value, chain;
2073 register struct obstack *ambient_obstack = current_obstack;
2074 current_obstack = &temporary_obstack;
2076 node = tree_cons (purpose, value, chain);
2077 current_obstack = ambient_obstack;
2081 /* Same as `tree_cons', but save this node if the function's RTL is saved. */
2084 saveable_tree_cons (purpose, value, chain)
2085 tree purpose, value, chain;
2088 register struct obstack *ambient_obstack = current_obstack;
2089 current_obstack = saveable_obstack;
2091 node = tree_cons (purpose, value, chain);
2092 current_obstack = ambient_obstack;
2096 /* Return the size nominally occupied by an object of type TYPE
2097 when it resides in memory. The value is measured in units of bytes,
2098 and its data type is that normally used for type sizes
2099 (which is the first type created by make_signed_type or
2100 make_unsigned_type). */
2103 size_in_bytes (type)
2108 if (type == error_mark_node)
2109 return integer_zero_node;
2110 type = TYPE_MAIN_VARIANT (type);
2111 if (TYPE_SIZE (type) == 0)
2113 incomplete_type_error (NULL_TREE, type);
2114 return integer_zero_node;
2116 t = size_binop (CEIL_DIV_EXPR, TYPE_SIZE (type),
2117 size_int (BITS_PER_UNIT));
2118 if (TREE_CODE (t) == INTEGER_CST)
2119 force_fit_type (t, 0);
2123 /* Return the size of TYPE (in bytes) as an integer,
2124 or return -1 if the size can vary. */
2127 int_size_in_bytes (type)
2131 if (type == error_mark_node)
2133 type = TYPE_MAIN_VARIANT (type);
2134 if (TYPE_SIZE (type) == 0)
2136 if (TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
2138 if (TREE_INT_CST_HIGH (TYPE_SIZE (type)) != 0)
2140 tree t = size_binop (CEIL_DIV_EXPR, TYPE_SIZE (type),
2141 size_int (BITS_PER_UNIT));
2142 return TREE_INT_CST_LOW (t);
2144 size = TREE_INT_CST_LOW (TYPE_SIZE (type));
2145 return (size + BITS_PER_UNIT - 1) / BITS_PER_UNIT;
2148 /* Return, as a tree node, the number of elements for TYPE (which is an
2149 ARRAY_TYPE) minus one. This counts only elements of the top array.
2151 Don't let any SAVE_EXPRs escape; if we are called as part of a cleanup
2152 action, they would get unsaved. */
2155 array_type_nelts (type)
2158 tree index_type, min, max;
2160 /* If they did it with unspecified bounds, then we should have already
2161 given an error about it before we got here. */
2162 if (! TYPE_DOMAIN (type))
2163 return error_mark_node;
2165 index_type = TYPE_DOMAIN (type);
2166 min = TYPE_MIN_VALUE (index_type);
2167 max = TYPE_MAX_VALUE (index_type);
2169 if (! TREE_CONSTANT (min))
2172 if (TREE_CODE (min) == SAVE_EXPR)
2173 min = build (RTL_EXPR, TREE_TYPE (TYPE_MIN_VALUE (index_type)), 0,
2174 SAVE_EXPR_RTL (min));
2176 min = TYPE_MIN_VALUE (index_type);
2179 if (! TREE_CONSTANT (max))
2182 if (TREE_CODE (max) == SAVE_EXPR)
2183 max = build (RTL_EXPR, TREE_TYPE (TYPE_MAX_VALUE (index_type)), 0,
2184 SAVE_EXPR_RTL (max));
2186 max = TYPE_MAX_VALUE (index_type);
2189 return (integer_zerop (min)
2191 : fold (build (MINUS_EXPR, TREE_TYPE (max), max, min)));
2194 /* Return nonzero if arg is static -- a reference to an object in
2195 static storage. This is not the same as the C meaning of `static'. */
2201 switch (TREE_CODE (arg))
2204 /* Nested functions aren't static, since taking their address
2205 involves a trampoline. */
2206 return decl_function_context (arg) == 0 || DECL_NO_STATIC_CHAIN (arg);
2208 return TREE_STATIC (arg) || DECL_EXTERNAL (arg);
2211 return TREE_STATIC (arg);
2216 /* If we are referencing a bitfield, we can't evaluate an
2217 ADDR_EXPR at compile time and so it isn't a constant. */
2219 return (! DECL_BIT_FIELD (TREE_OPERAND (arg, 1))
2220 && staticp (TREE_OPERAND (arg, 0)));
2226 /* This case is technically correct, but results in setting
2227 TREE_CONSTANT on ADDR_EXPRs that cannot be evaluated at
2230 return TREE_CONSTANT (TREE_OPERAND (arg, 0));
2234 if (TREE_CODE (TYPE_SIZE (TREE_TYPE (arg))) == INTEGER_CST
2235 && TREE_CODE (TREE_OPERAND (arg, 1)) == INTEGER_CST)
2236 return staticp (TREE_OPERAND (arg, 0));
2242 /* Wrap a SAVE_EXPR around EXPR, if appropriate.
2243 Do this to any expression which may be used in more than one place,
2244 but must be evaluated only once.
2246 Normally, expand_expr would reevaluate the expression each time.
2247 Calling save_expr produces something that is evaluated and recorded
2248 the first time expand_expr is called on it. Subsequent calls to
2249 expand_expr just reuse the recorded value.
2251 The call to expand_expr that generates code that actually computes
2252 the value is the first call *at compile time*. Subsequent calls
2253 *at compile time* generate code to use the saved value.
2254 This produces correct result provided that *at run time* control
2255 always flows through the insns made by the first expand_expr
2256 before reaching the other places where the save_expr was evaluated.
2257 You, the caller of save_expr, must make sure this is so.
2259 Constants, and certain read-only nodes, are returned with no
2260 SAVE_EXPR because that is safe. Expressions containing placeholders
2261 are not touched; see tree.def for an explanation of what these
2268 register tree t = fold (expr);
2270 /* We don't care about whether this can be used as an lvalue in this
2272 while (TREE_CODE (t) == NON_LVALUE_EXPR)
2273 t = TREE_OPERAND (t, 0);
2275 /* If the tree evaluates to a constant, then we don't want to hide that
2276 fact (i.e. this allows further folding, and direct checks for constants).
2277 However, a read-only object that has side effects cannot be bypassed.
2278 Since it is no problem to reevaluate literals, we just return the
2281 if (TREE_CONSTANT (t) || (TREE_READONLY (t) && ! TREE_SIDE_EFFECTS (t))
2282 || TREE_CODE (t) == SAVE_EXPR || TREE_CODE (t) == ERROR_MARK)
2285 /* If T contains a PLACEHOLDER_EXPR, we must evaluate it each time, since
2286 it means that the size or offset of some field of an object depends on
2287 the value within another field.
2289 Note that it must not be the case that T contains both a PLACEHOLDER_EXPR
2290 and some variable since it would then need to be both evaluated once and
2291 evaluated more than once. Front-ends must assure this case cannot
2292 happen by surrounding any such subexpressions in their own SAVE_EXPR
2293 and forcing evaluation at the proper time. */
2294 if (contains_placeholder_p (t))
2297 t = build (SAVE_EXPR, TREE_TYPE (expr), t, current_function_decl, NULL_TREE);
2299 /* This expression might be placed ahead of a jump to ensure that the
2300 value was computed on both sides of the jump. So make sure it isn't
2301 eliminated as dead. */
2302 TREE_SIDE_EFFECTS (t) = 1;
2306 /* Arrange for an expression to be expanded multiple independent
2307 times. This is useful for cleanup actions, as the backend can
2308 expand them multiple times in different places. */
2316 /* If this is already protected, no sense in protecting it again. */
2317 if (TREE_CODE (expr) == UNSAVE_EXPR)
2320 t = build1 (UNSAVE_EXPR, TREE_TYPE (expr), expr);
2321 TREE_SIDE_EFFECTS (t) = TREE_SIDE_EFFECTS (expr);
2325 /* Modify a tree in place so that all the evaluate only once things
2326 are cleared out. Return the EXPR given. */
2329 unsave_expr_now (expr)
2332 enum tree_code code;
2336 if (expr == NULL_TREE)
2339 code = TREE_CODE (expr);
2340 first_rtl = tree_code_length [(int) code];
2344 SAVE_EXPR_RTL (expr) = 0;
2349 TREE_OPERAND (expr, 1) = TREE_OPERAND (expr, 3);
2350 TREE_OPERAND (expr, 3) = NULL_TREE;
2354 /* I don't yet know how to emit a sequence multiple times. */
2355 if (RTL_EXPR_SEQUENCE (expr) != 0)
2361 CALL_EXPR_RTL (expr) = 0;
2362 if (TREE_OPERAND (expr, 1)
2363 && TREE_CODE (TREE_OPERAND (expr, 1)) == TREE_LIST)
2365 tree exp = TREE_OPERAND (expr, 1);
2368 unsave_expr_now (TREE_VALUE (exp));
2369 exp = TREE_CHAIN (exp);
2375 case WITH_CLEANUP_EXPR:
2376 /* Should be defined to be 2. */
2380 case METHOD_CALL_EXPR:
2385 switch (TREE_CODE_CLASS (code))
2387 case 'c': /* a constant */
2388 case 't': /* a type node */
2389 case 'x': /* something random, like an identifier or an ERROR_MARK. */
2390 case 'd': /* A decl node */
2391 case 'b': /* A block node */
2394 case 'e': /* an expression */
2395 case 'r': /* a reference */
2396 case 's': /* an expression with side effects */
2397 case '<': /* a comparison expression */
2398 case '2': /* a binary arithmetic expression */
2399 case '1': /* a unary arithmetic expression */
2400 for (i = first_rtl - 1; i >= 0; i--)
2401 unsave_expr_now (TREE_OPERAND (expr, i));
2409 /* Return 1 if EXP contains a PLACEHOLDER_EXPR; i.e., if it represents a size
2410 or offset that depends on a field within a record. */
2413 contains_placeholder_p (exp)
2416 register enum tree_code code = TREE_CODE (exp);
2418 /* If we have a WITH_RECORD_EXPR, it "cancels" any PLACEHOLDER_EXPR
2419 in it since it is supplying a value for it. */
2420 if (code == WITH_RECORD_EXPR)
2422 else if (code == PLACEHOLDER_EXPR)
2425 switch (TREE_CODE_CLASS (code))
2428 /* Don't look at any PLACEHOLDER_EXPRs that might be in index or bit
2429 position computations since they will be converted into a
2430 WITH_RECORD_EXPR involving the reference, which will assume
2431 here will be valid. */
2432 return contains_placeholder_p (TREE_OPERAND (exp, 0));
2440 /* Ignoring the first operand isn't quite right, but works best. */
2441 return contains_placeholder_p (TREE_OPERAND (exp, 1));
2448 return (contains_placeholder_p (TREE_OPERAND (exp, 0))
2449 || contains_placeholder_p (TREE_OPERAND (exp, 1))
2450 || contains_placeholder_p (TREE_OPERAND (exp, 2)));
2453 return (SAVE_EXPR_RTL (exp) == 0
2454 && contains_placeholder_p (TREE_OPERAND (exp, 0)));
2457 switch (tree_code_length[(int) code])
2460 return contains_placeholder_p (TREE_OPERAND (exp, 0));
2462 return (contains_placeholder_p (TREE_OPERAND (exp, 0))
2463 || contains_placeholder_p (TREE_OPERAND (exp, 1)));
2470 /* Given a tree EXP, a FIELD_DECL F, and a replacement value R,
2471 return a tree with all occurrences of references to F in a
2472 PLACEHOLDER_EXPR replaced by R. Note that we assume here that EXP
2473 contains only arithmetic expressions. */
2476 substitute_in_expr (exp, f, r)
2481 enum tree_code code = TREE_CODE (exp);
2486 switch (TREE_CODE_CLASS (code))
2493 if (code == PLACEHOLDER_EXPR)
2501 switch (tree_code_length[(int) code])
2504 op0 = substitute_in_expr (TREE_OPERAND (exp, 0), f, r);
2505 if (op0 == TREE_OPERAND (exp, 0))
2508 new = fold (build1 (code, TREE_TYPE (exp), op0));
2512 /* An RTL_EXPR cannot contain a PLACEHOLDER_EXPR; a CONSTRUCTOR
2513 could, but we don't support it. */
2514 if (code == RTL_EXPR)
2516 else if (code == CONSTRUCTOR)
2519 op0 = substitute_in_expr (TREE_OPERAND (exp, 0), f, r);
2520 op1 = substitute_in_expr (TREE_OPERAND (exp, 1), f, r);
2521 if (op0 == TREE_OPERAND (exp, 0) && op1 == TREE_OPERAND (exp, 1))
2524 new = fold (build (code, TREE_TYPE (exp), op0, op1));
2528 /* It cannot be that anything inside a SAVE_EXPR contains a
2529 PLACEHOLDER_EXPR. */
2530 if (code == SAVE_EXPR)
2533 if (code != COND_EXPR)
2536 op0 = substitute_in_expr (TREE_OPERAND (exp, 0), f, r);
2537 op1 = substitute_in_expr (TREE_OPERAND (exp, 1), f, r);
2538 op2 = substitute_in_expr (TREE_OPERAND (exp, 2), f, r);
2539 if (op0 == TREE_OPERAND (exp, 0) && op1 == TREE_OPERAND (exp, 1)
2540 && op2 == TREE_OPERAND (exp, 2))
2543 new = fold (build (code, TREE_TYPE (exp), op0, op1, op2));
2552 /* If this expression is getting a value from a PLACEHOLDER_EXPR
2553 and it is the right field, replace it with R. */
2554 for (inner = TREE_OPERAND (exp, 0);
2555 TREE_CODE_CLASS (TREE_CODE (inner)) == 'r';
2556 inner = TREE_OPERAND (inner, 0))
2558 if (TREE_CODE (inner) == PLACEHOLDER_EXPR
2559 && TREE_OPERAND (exp, 1) == f)
2562 /* If this expression hasn't been completed let, leave it
2564 if (TREE_CODE (inner) == PLACEHOLDER_EXPR
2565 && TREE_TYPE (inner) == 0)
2568 op0 = substitute_in_expr (TREE_OPERAND (exp, 0), f, r);
2569 if (op0 == TREE_OPERAND (exp, 0))
2572 new = fold (build (code, TREE_TYPE (exp), op0,
2573 TREE_OPERAND (exp, 1)));
2577 op0 = substitute_in_expr (TREE_OPERAND (exp, 0), f, r);
2578 op1 = substitute_in_expr (TREE_OPERAND (exp, 1), f, r);
2579 op2 = substitute_in_expr (TREE_OPERAND (exp, 2), f, r);
2580 if (op0 == TREE_OPERAND (exp, 0) && op1 == TREE_OPERAND (exp, 1)
2581 && op2 == TREE_OPERAND (exp, 2))
2584 new = fold (build (code, TREE_TYPE (exp), op0, op1, op2));
2589 op0 = substitute_in_expr (TREE_OPERAND (exp, 0), f, r);
2590 if (op0 == TREE_OPERAND (exp, 0))
2593 new = fold (build1 (code, TREE_TYPE (exp), op0));
2598 /* If it wasn't one of the cases we handle, give up. */
2602 TREE_READONLY (new) = TREE_READONLY (exp);
2606 /* Stabilize a reference so that we can use it any number of times
2607 without causing its operands to be evaluated more than once.
2608 Returns the stabilized reference. This works by means of save_expr,
2609 so see the caveats in the comments about save_expr.
2611 Also allows conversion expressions whose operands are references.
2612 Any other kind of expression is returned unchanged. */
2615 stabilize_reference (ref)
2618 register tree result;
2619 register enum tree_code code = TREE_CODE (ref);
2626 /* No action is needed in this case. */
2632 case FIX_TRUNC_EXPR:
2633 case FIX_FLOOR_EXPR:
2634 case FIX_ROUND_EXPR:
2636 result = build_nt (code, stabilize_reference (TREE_OPERAND (ref, 0)));
2640 result = build_nt (INDIRECT_REF,
2641 stabilize_reference_1 (TREE_OPERAND (ref, 0)));
2645 result = build_nt (COMPONENT_REF,
2646 stabilize_reference (TREE_OPERAND (ref, 0)),
2647 TREE_OPERAND (ref, 1));
2651 result = build_nt (BIT_FIELD_REF,
2652 stabilize_reference (TREE_OPERAND (ref, 0)),
2653 stabilize_reference_1 (TREE_OPERAND (ref, 1)),
2654 stabilize_reference_1 (TREE_OPERAND (ref, 2)));
2658 result = build_nt (ARRAY_REF,
2659 stabilize_reference (TREE_OPERAND (ref, 0)),
2660 stabilize_reference_1 (TREE_OPERAND (ref, 1)));
2664 /* We cannot wrap the first expression in a SAVE_EXPR, as then
2665 it wouldn't be ignored. This matters when dealing with
2667 return stabilize_reference_1 (ref);
2670 result = build1 (INDIRECT_REF, TREE_TYPE (ref),
2671 save_expr (build1 (ADDR_EXPR,
2672 build_pointer_type (TREE_TYPE (ref)),
2677 /* If arg isn't a kind of lvalue we recognize, make no change.
2678 Caller should recognize the error for an invalid lvalue. */
2683 return error_mark_node;
2686 TREE_TYPE (result) = TREE_TYPE (ref);
2687 TREE_READONLY (result) = TREE_READONLY (ref);
2688 TREE_SIDE_EFFECTS (result) = TREE_SIDE_EFFECTS (ref);
2689 TREE_THIS_VOLATILE (result) = TREE_THIS_VOLATILE (ref);
2690 TREE_RAISES (result) = TREE_RAISES (ref);
2695 /* Subroutine of stabilize_reference; this is called for subtrees of
2696 references. Any expression with side-effects must be put in a SAVE_EXPR
2697 to ensure that it is only evaluated once.
2699 We don't put SAVE_EXPR nodes around everything, because assigning very
2700 simple expressions to temporaries causes us to miss good opportunities
2701 for optimizations. Among other things, the opportunity to fold in the
2702 addition of a constant into an addressing mode often gets lost, e.g.
2703 "y[i+1] += x;". In general, we take the approach that we should not make
2704 an assignment unless we are forced into it - i.e., that any non-side effect
2705 operator should be allowed, and that cse should take care of coalescing
2706 multiple utterances of the same expression should that prove fruitful. */
2709 stabilize_reference_1 (e)
2712 register tree result;
2713 register enum tree_code code = TREE_CODE (e);
2715 /* We cannot ignore const expressions because it might be a reference
2716 to a const array but whose index contains side-effects. But we can
2717 ignore things that are actual constant or that already have been
2718 handled by this function. */
2720 if (TREE_CONSTANT (e) || code == SAVE_EXPR)
2723 switch (TREE_CODE_CLASS (code))
2733 /* If the expression has side-effects, then encase it in a SAVE_EXPR
2734 so that it will only be evaluated once. */
2735 /* The reference (r) and comparison (<) classes could be handled as
2736 below, but it is generally faster to only evaluate them once. */
2737 if (TREE_SIDE_EFFECTS (e))
2738 return save_expr (e);
2742 /* Constants need no processing. In fact, we should never reach
2747 /* Division is slow and tends to be compiled with jumps,
2748 especially the division by powers of 2 that is often
2749 found inside of an array reference. So do it just once. */
2750 if (code == TRUNC_DIV_EXPR || code == TRUNC_MOD_EXPR
2751 || code == FLOOR_DIV_EXPR || code == FLOOR_MOD_EXPR
2752 || code == CEIL_DIV_EXPR || code == CEIL_MOD_EXPR
2753 || code == ROUND_DIV_EXPR || code == ROUND_MOD_EXPR)
2754 return save_expr (e);
2755 /* Recursively stabilize each operand. */
2756 result = build_nt (code, stabilize_reference_1 (TREE_OPERAND (e, 0)),
2757 stabilize_reference_1 (TREE_OPERAND (e, 1)));
2761 /* Recursively stabilize each operand. */
2762 result = build_nt (code, stabilize_reference_1 (TREE_OPERAND (e, 0)));
2769 TREE_TYPE (result) = TREE_TYPE (e);
2770 TREE_READONLY (result) = TREE_READONLY (e);
2771 TREE_SIDE_EFFECTS (result) = TREE_SIDE_EFFECTS (e);
2772 TREE_THIS_VOLATILE (result) = TREE_THIS_VOLATILE (e);
2773 TREE_RAISES (result) = TREE_RAISES (e);
2778 /* Low-level constructors for expressions. */
2780 /* Build an expression of code CODE, data type TYPE,
2781 and operands as specified by the arguments ARG1 and following arguments.
2782 Expressions and reference nodes can be created this way.
2783 Constants, decls, types and misc nodes cannot be. */
2786 build VPROTO((enum tree_code code, tree tt, ...))
2789 enum tree_code code;
2794 register int length;
2800 code = va_arg (p, enum tree_code);
2801 tt = va_arg (p, tree);
2804 t = make_node (code);
2805 length = tree_code_length[(int) code];
2810 /* This is equivalent to the loop below, but faster. */
2811 register tree arg0 = va_arg (p, tree);
2812 register tree arg1 = va_arg (p, tree);
2813 TREE_OPERAND (t, 0) = arg0;
2814 TREE_OPERAND (t, 1) = arg1;
2815 if ((arg0 && TREE_SIDE_EFFECTS (arg0))
2816 || (arg1 && TREE_SIDE_EFFECTS (arg1)))
2817 TREE_SIDE_EFFECTS (t) = 1;
2819 = (arg0 && TREE_RAISES (arg0)) || (arg1 && TREE_RAISES (arg1));
2821 else if (length == 1)
2823 register tree arg0 = va_arg (p, tree);
2825 /* Call build1 for this! */
2826 if (TREE_CODE_CLASS (code) != 's')
2828 TREE_OPERAND (t, 0) = arg0;
2829 if (arg0 && TREE_SIDE_EFFECTS (arg0))
2830 TREE_SIDE_EFFECTS (t) = 1;
2831 TREE_RAISES (t) = (arg0 && TREE_RAISES (arg0));
2835 for (i = 0; i < length; i++)
2837 register tree operand = va_arg (p, tree);
2838 TREE_OPERAND (t, i) = operand;
2841 if (TREE_SIDE_EFFECTS (operand))
2842 TREE_SIDE_EFFECTS (t) = 1;
2843 if (TREE_RAISES (operand))
2844 TREE_RAISES (t) = 1;
2852 /* Same as above, but only builds for unary operators.
2853 Saves lions share of calls to `build'; cuts down use
2854 of varargs, which is expensive for RISC machines. */
2857 build1 (code, type, node)
2858 enum tree_code code;
2862 register struct obstack *obstack = expression_obstack;
2863 register int i, length;
2864 register tree_node_kind kind;
2867 #ifdef GATHER_STATISTICS
2868 if (TREE_CODE_CLASS (code) == 'r')
2874 length = sizeof (struct tree_exp);
2876 t = (tree) obstack_alloc (obstack, length);
2878 #ifdef GATHER_STATISTICS
2879 tree_node_counts[(int)kind]++;
2880 tree_node_sizes[(int)kind] += length;
2883 for (i = (length / sizeof (int)) - 1; i >= 0; i--)
2886 TREE_TYPE (t) = type;
2887 TREE_SET_CODE (t, code);
2889 if (obstack == &permanent_obstack)
2890 TREE_PERMANENT (t) = 1;
2892 TREE_OPERAND (t, 0) = node;
2895 if (TREE_SIDE_EFFECTS (node))
2896 TREE_SIDE_EFFECTS (t) = 1;
2897 if (TREE_RAISES (node))
2898 TREE_RAISES (t) = 1;
2904 /* Similar except don't specify the TREE_TYPE
2905 and leave the TREE_SIDE_EFFECTS as 0.
2906 It is permissible for arguments to be null,
2907 or even garbage if their values do not matter. */
2910 build_nt VPROTO((enum tree_code code, ...))
2913 enum tree_code code;
2917 register int length;
2923 code = va_arg (p, enum tree_code);
2926 t = make_node (code);
2927 length = tree_code_length[(int) code];
2929 for (i = 0; i < length; i++)
2930 TREE_OPERAND (t, i) = va_arg (p, tree);
2936 /* Similar to `build_nt', except we build
2937 on the temp_decl_obstack, regardless. */
2940 build_parse_node VPROTO((enum tree_code code, ...))
2943 enum tree_code code;
2945 register struct obstack *ambient_obstack = expression_obstack;
2948 register int length;
2954 code = va_arg (p, enum tree_code);
2957 expression_obstack = &temp_decl_obstack;
2959 t = make_node (code);
2960 length = tree_code_length[(int) code];
2962 for (i = 0; i < length; i++)
2963 TREE_OPERAND (t, i) = va_arg (p, tree);
2966 expression_obstack = ambient_obstack;
2971 /* Commented out because this wants to be done very
2972 differently. See cp-lex.c. */
2974 build_op_identifier (op1, op2)
2977 register tree t = make_node (OP_IDENTIFIER);
2978 TREE_PURPOSE (t) = op1;
2979 TREE_VALUE (t) = op2;
2984 /* Create a DECL_... node of code CODE, name NAME and data type TYPE.
2985 We do NOT enter this node in any sort of symbol table.
2987 layout_decl is used to set up the decl's storage layout.
2988 Other slots are initialized to 0 or null pointers. */
2991 build_decl (code, name, type)
2992 enum tree_code code;
2997 t = make_node (code);
2999 /* if (type == error_mark_node)
3000 type = integer_type_node; */
3001 /* That is not done, deliberately, so that having error_mark_node
3002 as the type can suppress useless errors in the use of this variable. */
3004 DECL_NAME (t) = name;
3005 DECL_ASSEMBLER_NAME (t) = name;
3006 TREE_TYPE (t) = type;
3008 if (code == VAR_DECL || code == PARM_DECL || code == RESULT_DECL)
3010 else if (code == FUNCTION_DECL)
3011 DECL_MODE (t) = FUNCTION_MODE;
3016 /* BLOCK nodes are used to represent the structure of binding contours
3017 and declarations, once those contours have been exited and their contents
3018 compiled. This information is used for outputting debugging info. */
3021 build_block (vars, tags, subblocks, supercontext, chain)
3022 tree vars, tags, subblocks, supercontext, chain;
3024 register tree block = make_node (BLOCK);
3025 BLOCK_VARS (block) = vars;
3026 BLOCK_TYPE_TAGS (block) = tags;
3027 BLOCK_SUBBLOCKS (block) = subblocks;
3028 BLOCK_SUPERCONTEXT (block) = supercontext;
3029 BLOCK_CHAIN (block) = chain;
3033 /* Return a declaration like DDECL except that its DECL_MACHINE_ATTRIBUTE
3037 build_decl_attribute_variant (ddecl, attribute)
3038 tree ddecl, attribute;
3040 DECL_MACHINE_ATTRIBUTES (ddecl) = attribute;
3044 /* Return a type like TTYPE except that its TYPE_ATTRIBUTE
3047 Record such modified types already made so we don't make duplicates. */
3050 build_type_attribute_variant (ttype, attribute)
3051 tree ttype, attribute;
3053 if ( ! attribute_list_equal (TYPE_ATTRIBUTES (ttype), attribute))
3055 register int hashcode;
3056 register struct obstack *ambient_obstack = current_obstack;
3059 if (ambient_obstack != &permanent_obstack)
3060 current_obstack = TYPE_OBSTACK (ttype);
3062 ntype = copy_node (ttype);
3063 current_obstack = ambient_obstack;
3065 TYPE_POINTER_TO (ntype) = 0;
3066 TYPE_REFERENCE_TO (ntype) = 0;
3067 TYPE_ATTRIBUTES (ntype) = attribute;
3069 /* Create a new main variant of TYPE. */
3070 TYPE_MAIN_VARIANT (ntype) = ntype;
3071 TYPE_NEXT_VARIANT (ntype) = 0;
3072 TYPE_READONLY (ntype) = TYPE_VOLATILE (ntype) = 0;
3074 hashcode = TYPE_HASH (TREE_CODE (ntype))
3075 + TYPE_HASH (TREE_TYPE (ntype))
3076 + attribute_hash_list (attribute);
3078 switch (TREE_CODE (ntype))
3081 hashcode += TYPE_HASH (TYPE_ARG_TYPES (ntype));
3084 hashcode += TYPE_HASH (TYPE_DOMAIN (ntype));
3087 hashcode += TYPE_HASH (TYPE_MAX_VALUE (ntype));
3090 hashcode += TYPE_HASH (TYPE_PRECISION (ntype));
3094 ntype = type_hash_canon (hashcode, ntype);
3095 ttype = build_type_variant (ntype, TYPE_READONLY (ttype),
3096 TYPE_VOLATILE (ttype));
3102 /* Return a 1 if ATTR_NAME and ATTR_ARGS is valid for either declaration DECL
3103 or type TYPE and 0 otherwise. Validity is determined the configuration
3104 macros VALID_MACHINE_DECL_ATTRIBUTE and VALID_MACHINE_TYPE_ATTRIBUTE. */
3107 valid_machine_attribute (attr_name, attr_args, decl, type)
3108 tree attr_name, attr_args;
3113 tree decl_attr_list = decl != 0 ? DECL_MACHINE_ATTRIBUTES (decl) : 0;
3114 tree type_attr_list = TYPE_ATTRIBUTES (type);
3116 if (TREE_CODE (attr_name) != IDENTIFIER_NODE)
3119 #ifdef VALID_MACHINE_DECL_ATTRIBUTE
3121 && VALID_MACHINE_DECL_ATTRIBUTE (decl, decl_attr_list, attr_name, attr_args))
3123 tree attr = lookup_attribute (IDENTIFIER_POINTER (attr_name),
3126 if (attr != NULL_TREE)
3128 /* Override existing arguments. Declarations are unique so we can
3129 modify this in place. */
3130 TREE_VALUE (attr) = attr_args;
3134 decl_attr_list = tree_cons (attr_name, attr_args, decl_attr_list);
3135 decl = build_decl_attribute_variant (decl, decl_attr_list);
3142 #ifdef VALID_MACHINE_TYPE_ATTRIBUTE
3143 if (VALID_MACHINE_TYPE_ATTRIBUTE (type, type_attr_list, attr_name, attr_args))
3145 tree attr = lookup_attribute (IDENTIFIER_POINTER (attr_name),
3148 if (attr != NULL_TREE)
3150 /* Override existing arguments.
3151 ??? This currently works since attribute arguments are not
3152 included in `attribute_hash_list'. Something more complicated
3153 may be needed in the future. */
3154 TREE_VALUE (attr) = attr_args;
3158 type_attr_list = tree_cons (attr_name, attr_args, type_attr_list);
3159 type = build_type_attribute_variant (type, type_attr_list);
3162 TREE_TYPE (decl) = type;
3166 /* Handle putting a type attribute on pointer-to-function-type by putting
3167 the attribute on the function type. */
3168 else if (TREE_CODE (type) == POINTER_TYPE
3169 && TREE_CODE (TREE_TYPE (type)) == FUNCTION_TYPE
3170 && VALID_MACHINE_TYPE_ATTRIBUTE (TREE_TYPE (type), type_attr_list,
3171 attr_name, attr_args))
3173 tree inner_type = TREE_TYPE (type);
3174 tree inner_attr_list = TYPE_ATTRIBUTES (inner_type);
3175 tree attr = lookup_attribute (IDENTIFIER_POINTER (attr_name),
3178 if (attr != NULL_TREE)
3179 TREE_VALUE (attr) = attr_args;
3182 inner_attr_list = tree_cons (attr_name, attr_args, inner_attr_list);
3183 inner_type = build_type_attribute_variant (inner_type,
3188 TREE_TYPE (decl) = build_pointer_type (inner_type);
3197 /* Return non-zero if IDENT is a valid name for attribute ATTR,
3200 We try both `text' and `__text__', ATTR may be either one. */
3201 /* ??? It might be a reasonable simplification to require ATTR to be only
3202 `text'. One might then also require attribute lists to be stored in
3203 their canonicalized form. */
3206 is_attribute_p (attr, ident)
3210 int ident_len, attr_len;
3213 if (TREE_CODE (ident) != IDENTIFIER_NODE)
3216 if (strcmp (attr, IDENTIFIER_POINTER (ident)) == 0)
3219 p = IDENTIFIER_POINTER (ident);
3220 ident_len = strlen (p);
3221 attr_len = strlen (attr);
3223 /* If ATTR is `__text__', IDENT must be `text'; and vice versa. */
3227 || attr[attr_len - 2] != '_'
3228 || attr[attr_len - 1] != '_')
3230 if (ident_len == attr_len - 4
3231 && strncmp (attr + 2, p, attr_len - 4) == 0)
3236 if (ident_len == attr_len + 4
3237 && p[0] == '_' && p[1] == '_'
3238 && p[ident_len - 2] == '_' && p[ident_len - 1] == '_'
3239 && strncmp (attr, p + 2, attr_len) == 0)
3246 /* Given an attribute name and a list of attributes, return a pointer to the
3247 attribute's list element if the attribute is part of the list, or NULL_TREE
3251 lookup_attribute (attr_name, list)
3257 for (l = list; l; l = TREE_CHAIN (l))
3259 if (TREE_CODE (TREE_PURPOSE (l)) != IDENTIFIER_NODE)
3261 if (is_attribute_p (attr_name, TREE_PURPOSE (l)))
3268 /* Return an attribute list that is the union of a1 and a2. */
3271 merge_attributes (a1, a2)
3272 register tree a1, a2;
3276 /* Either one unset? Take the set one. */
3278 if (! (attributes = a1))
3281 /* One that completely contains the other? Take it. */
3283 else if (a2 && ! attribute_list_contained (a1, a2))
3284 if (attribute_list_contained (a2, a1))
3288 /* Pick the longest list, and hang on the other list. */
3289 /* ??? For the moment we punt on the issue of attrs with args. */
3291 if (list_length (a1) < list_length (a2))
3292 attributes = a2, a2 = a1;
3294 for (; a2; a2 = TREE_CHAIN (a2))
3295 if (lookup_attribute (IDENTIFIER_POINTER (TREE_PURPOSE (a2)),
3296 attributes) == NULL_TREE)
3298 a1 = copy_node (a2);
3299 TREE_CHAIN (a1) = attributes;
3306 /* Return a type like TYPE except that its TYPE_READONLY is CONSTP
3307 and its TYPE_VOLATILE is VOLATILEP.
3309 Such variant types already made are recorded so that duplicates
3312 A variant types should never be used as the type of an expression.
3313 Always copy the variant information into the TREE_READONLY
3314 and TREE_THIS_VOLATILE of the expression, and then give the expression
3315 as its type the "main variant", the variant whose TYPE_READONLY
3316 and TYPE_VOLATILE are zero. Use TYPE_MAIN_VARIANT to find the
3320 build_type_variant (type, constp, volatilep)
3322 int constp, volatilep;
3326 /* Treat any nonzero argument as 1. */
3328 volatilep = !!volatilep;
3330 /* Search the chain of variants to see if there is already one there just
3331 like the one we need to have. If so, use that existing one. We must
3332 preserve the TYPE_NAME, since there is code that depends on this. */
3334 for (t = TYPE_MAIN_VARIANT (type); t; t = TYPE_NEXT_VARIANT (t))
3335 if (constp == TYPE_READONLY (t) && volatilep == TYPE_VOLATILE (t)
3336 && TYPE_NAME (t) == TYPE_NAME (type))
3339 /* We need a new one. */
3341 t = build_type_copy (type);
3342 TYPE_READONLY (t) = constp;
3343 TYPE_VOLATILE (t) = volatilep;
3348 /* Create a new variant of TYPE, equivalent but distinct.
3349 This is so the caller can modify it. */
3352 build_type_copy (type)
3355 register tree t, m = TYPE_MAIN_VARIANT (type);
3356 register struct obstack *ambient_obstack = current_obstack;
3358 current_obstack = TYPE_OBSTACK (type);
3359 t = copy_node (type);
3360 current_obstack = ambient_obstack;
3362 TYPE_POINTER_TO (t) = 0;
3363 TYPE_REFERENCE_TO (t) = 0;
3365 /* Add this type to the chain of variants of TYPE. */
3366 TYPE_NEXT_VARIANT (t) = TYPE_NEXT_VARIANT (m);
3367 TYPE_NEXT_VARIANT (m) = t;
3372 /* Hashing of types so that we don't make duplicates.
3373 The entry point is `type_hash_canon'. */
3375 /* Each hash table slot is a bucket containing a chain
3376 of these structures. */
3380 struct type_hash *next; /* Next structure in the bucket. */
3381 int hashcode; /* Hash code of this type. */
3382 tree type; /* The type recorded here. */
3385 /* Now here is the hash table. When recording a type, it is added
3386 to the slot whose index is the hash code mod the table size.
3387 Note that the hash table is used for several kinds of types
3388 (function types, array types and array index range types, for now).
3389 While all these live in the same table, they are completely independent,
3390 and the hash code is computed differently for each of these. */
3392 #define TYPE_HASH_SIZE 59
3393 struct type_hash *type_hash_table[TYPE_HASH_SIZE];
3395 /* Compute a hash code for a list of types (chain of TREE_LIST nodes
3396 with types in the TREE_VALUE slots), by adding the hash codes
3397 of the individual types. */
3400 type_hash_list (list)
3403 register int hashcode;
3405 for (hashcode = 0, tail = list; tail; tail = TREE_CHAIN (tail))
3406 hashcode += TYPE_HASH (TREE_VALUE (tail));
3410 /* Look in the type hash table for a type isomorphic to TYPE.
3411 If one is found, return it. Otherwise return 0. */
3414 type_hash_lookup (hashcode, type)
3418 register struct type_hash *h;
3419 for (h = type_hash_table[hashcode % TYPE_HASH_SIZE]; h; h = h->next)
3420 if (h->hashcode == hashcode
3421 && TREE_CODE (h->type) == TREE_CODE (type)
3422 && TREE_TYPE (h->type) == TREE_TYPE (type)
3423 && attribute_list_equal (TYPE_ATTRIBUTES (h->type),
3424 TYPE_ATTRIBUTES (type))
3425 && (TYPE_MAX_VALUE (h->type) == TYPE_MAX_VALUE (type)
3426 || tree_int_cst_equal (TYPE_MAX_VALUE (h->type),
3427 TYPE_MAX_VALUE (type)))
3428 && (TYPE_MIN_VALUE (h->type) == TYPE_MIN_VALUE (type)
3429 || tree_int_cst_equal (TYPE_MIN_VALUE (h->type),
3430 TYPE_MIN_VALUE (type)))
3431 /* Note that TYPE_DOMAIN is TYPE_ARG_TYPES for FUNCTION_TYPE. */
3432 && (TYPE_DOMAIN (h->type) == TYPE_DOMAIN (type)
3433 || (TYPE_DOMAIN (h->type)
3434 && TREE_CODE (TYPE_DOMAIN (h->type)) == TREE_LIST
3435 && TYPE_DOMAIN (type)
3436 && TREE_CODE (TYPE_DOMAIN (type)) == TREE_LIST
3437 && type_list_equal (TYPE_DOMAIN (h->type),
3438 TYPE_DOMAIN (type)))))
3443 /* Add an entry to the type-hash-table
3444 for a type TYPE whose hash code is HASHCODE. */
3447 type_hash_add (hashcode, type)
3451 register struct type_hash *h;
3453 h = (struct type_hash *) oballoc (sizeof (struct type_hash));
3454 h->hashcode = hashcode;
3456 h->next = type_hash_table[hashcode % TYPE_HASH_SIZE];
3457 type_hash_table[hashcode % TYPE_HASH_SIZE] = h;
3460 /* Given TYPE, and HASHCODE its hash code, return the canonical
3461 object for an identical type if one already exists.
3462 Otherwise, return TYPE, and record it as the canonical object
3463 if it is a permanent object.
3465 To use this function, first create a type of the sort you want.
3466 Then compute its hash code from the fields of the type that
3467 make it different from other similar types.
3468 Then call this function and use the value.
3469 This function frees the type you pass in if it is a duplicate. */
3471 /* Set to 1 to debug without canonicalization. Never set by program. */
3472 int debug_no_type_hash = 0;
3475 type_hash_canon (hashcode, type)
3481 if (debug_no_type_hash)
3484 t1 = type_hash_lookup (hashcode, type);
3487 obstack_free (TYPE_OBSTACK (type), type);
3488 #ifdef GATHER_STATISTICS
3489 tree_node_counts[(int)t_kind]--;
3490 tree_node_sizes[(int)t_kind] -= sizeof (struct tree_type);
3495 /* If this is a permanent type, record it for later reuse. */
3496 if (TREE_PERMANENT (type))
3497 type_hash_add (hashcode, type);
3502 /* Compute a hash code for a list of attributes (chain of TREE_LIST nodes
3503 with names in the TREE_PURPOSE slots and args in the TREE_VALUE slots),
3504 by adding the hash codes of the individual attributes. */
3507 attribute_hash_list (list)
3510 register int hashcode;
3512 for (hashcode = 0, tail = list; tail; tail = TREE_CHAIN (tail))
3513 /* ??? Do we want to add in TREE_VALUE too? */
3514 hashcode += TYPE_HASH (TREE_PURPOSE (tail));
3518 /* Given two lists of attributes, return true if list l2 is
3519 equivalent to l1. */
3522 attribute_list_equal (l1, l2)
3525 return attribute_list_contained (l1, l2)
3526 && attribute_list_contained (l2, l1);
3529 /* Given two lists of attributes, return true if list L2 is
3530 completely contained within L1. */
3531 /* ??? This would be faster if attribute names were stored in a canonicalized
3532 form. Otherwise, if L1 uses `foo' and L2 uses `__foo__', the long method
3533 must be used to show these elements are equivalent (which they are). */
3534 /* ??? It's not clear that attributes with arguments will always be handled
3538 attribute_list_contained (l1, l2)
3541 register tree t1, t2;
3543 /* First check the obvious, maybe the lists are identical. */
3547 /* Maybe the lists are similar. */
3548 for (t1 = l1, t2 = l2;
3550 && TREE_PURPOSE (t1) == TREE_PURPOSE (t2)
3551 && TREE_VALUE (t1) == TREE_VALUE (t2);
3552 t1 = TREE_CHAIN (t1), t2 = TREE_CHAIN (t2));
3554 /* Maybe the lists are equal. */
3555 if (t1 == 0 && t2 == 0)
3558 for (; t2; t2 = TREE_CHAIN (t2))
3561 = lookup_attribute (IDENTIFIER_POINTER (TREE_PURPOSE (t2)), l1);
3563 if (attr == NULL_TREE)
3565 if (simple_cst_equal (TREE_VALUE (t2), TREE_VALUE (attr)) != 1)
3572 /* Given two lists of types
3573 (chains of TREE_LIST nodes with types in the TREE_VALUE slots)
3574 return 1 if the lists contain the same types in the same order.
3575 Also, the TREE_PURPOSEs must match. */
3578 type_list_equal (l1, l2)
3581 register tree t1, t2;
3583 for (t1 = l1, t2 = l2; t1 && t2; t1 = TREE_CHAIN (t1), t2 = TREE_CHAIN (t2))
3584 if (TREE_VALUE (t1) != TREE_VALUE (t2)
3585 || (TREE_PURPOSE (t1) != TREE_PURPOSE (t2)
3586 && ! (1 == simple_cst_equal (TREE_PURPOSE (t1), TREE_PURPOSE (t2))
3587 && (TREE_TYPE (TREE_PURPOSE (t1))
3588 == TREE_TYPE (TREE_PURPOSE (t2))))))
3594 /* Nonzero if integer constants T1 and T2
3595 represent the same constant value. */
3598 tree_int_cst_equal (t1, t2)
3603 if (t1 == 0 || t2 == 0)
3605 if (TREE_CODE (t1) == INTEGER_CST
3606 && TREE_CODE (t2) == INTEGER_CST
3607 && TREE_INT_CST_LOW (t1) == TREE_INT_CST_LOW (t2)
3608 && TREE_INT_CST_HIGH (t1) == TREE_INT_CST_HIGH (t2))
3613 /* Nonzero if integer constants T1 and T2 represent values that satisfy <.
3614 The precise way of comparison depends on their data type. */
3617 tree_int_cst_lt (t1, t2)
3623 if (!TREE_UNSIGNED (TREE_TYPE (t1)))
3624 return INT_CST_LT (t1, t2);
3625 return INT_CST_LT_UNSIGNED (t1, t2);
3628 /* Return an indication of the sign of the integer constant T.
3629 The return value is -1 if T < 0, 0 if T == 0, and 1 if T > 0.
3630 Note that -1 will never be returned it T's type is unsigned. */
3633 tree_int_cst_sgn (t)
3636 if (TREE_INT_CST_LOW (t) == 0 && TREE_INT_CST_HIGH (t) == 0)
3638 else if (TREE_UNSIGNED (TREE_TYPE (t)))
3640 else if (TREE_INT_CST_HIGH (t) < 0)
3646 /* Compare two constructor-element-type constants. Return 1 if the lists
3647 are known to be equal; otherwise return 0. */
3650 simple_cst_list_equal (l1, l2)
3653 while (l1 != NULL_TREE && l2 != NULL_TREE)
3655 if (simple_cst_equal (TREE_VALUE (l1), TREE_VALUE (l2)) != 1)
3658 l1 = TREE_CHAIN (l1);
3659 l2 = TREE_CHAIN (l2);
3665 /* Return truthvalue of whether T1 is the same tree structure as T2.
3666 Return 1 if they are the same.
3667 Return 0 if they are understandably different.
3668 Return -1 if either contains tree structure not understood by
3672 simple_cst_equal (t1, t2)
3675 register enum tree_code code1, code2;
3680 if (t1 == 0 || t2 == 0)
3683 code1 = TREE_CODE (t1);
3684 code2 = TREE_CODE (t2);
3686 if (code1 == NOP_EXPR || code1 == CONVERT_EXPR || code1 == NON_LVALUE_EXPR)
3687 if (code2 == NOP_EXPR || code2 == CONVERT_EXPR || code2 == NON_LVALUE_EXPR)
3688 return simple_cst_equal (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0));
3690 return simple_cst_equal (TREE_OPERAND (t1, 0), t2);
3691 else if (code2 == NOP_EXPR || code2 == CONVERT_EXPR
3692 || code2 == NON_LVALUE_EXPR)
3693 return simple_cst_equal (t1, TREE_OPERAND (t2, 0));
3701 return TREE_INT_CST_LOW (t1) == TREE_INT_CST_LOW (t2)
3702 && TREE_INT_CST_HIGH (t1) == TREE_INT_CST_HIGH (t2);
3705 return REAL_VALUES_EQUAL (TREE_REAL_CST (t1), TREE_REAL_CST (t2));
3708 return TREE_STRING_LENGTH (t1) == TREE_STRING_LENGTH (t2)
3709 && !bcmp (TREE_STRING_POINTER (t1), TREE_STRING_POINTER (t2),
3710 TREE_STRING_LENGTH (t1));
3716 return simple_cst_equal (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0));
3719 cmp = simple_cst_equal (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0));
3722 return simple_cst_list_equal (TREE_OPERAND (t1, 1), TREE_OPERAND (t2, 1));
3725 /* Special case: if either target is an unallocated VAR_DECL,
3726 it means that it's going to be unified with whatever the
3727 TARGET_EXPR is really supposed to initialize, so treat it
3728 as being equivalent to anything. */
3729 if ((TREE_CODE (TREE_OPERAND (t1, 0)) == VAR_DECL
3730 && DECL_NAME (TREE_OPERAND (t1, 0)) == NULL_TREE
3731 && DECL_RTL (TREE_OPERAND (t1, 0)) == 0)
3732 || (TREE_CODE (TREE_OPERAND (t2, 0)) == VAR_DECL
3733 && DECL_NAME (TREE_OPERAND (t2, 0)) == NULL_TREE
3734 && DECL_RTL (TREE_OPERAND (t2, 0)) == 0))
3737 cmp = simple_cst_equal (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0));
3740 return simple_cst_equal (TREE_OPERAND (t1, 1), TREE_OPERAND (t2, 1));
3742 case WITH_CLEANUP_EXPR:
3743 cmp = simple_cst_equal (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0));
3746 return simple_cst_equal (TREE_OPERAND (t1, 2), TREE_OPERAND (t1, 2));
3749 if (TREE_OPERAND (t1, 1) == TREE_OPERAND (t2, 1))
3750 return simple_cst_equal (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0));
3760 /* This general rule works for most tree codes. All exceptions should be
3761 handled above. If this is a language-specific tree code, we can't
3762 trust what might be in the operand, so say we don't know
3765 >= sizeof standard_tree_code_type / sizeof standard_tree_code_type[0])
3768 switch (TREE_CODE_CLASS (code1))
3778 for (i=0; i<tree_code_length[(int) code1]; ++i)
3780 cmp = simple_cst_equal (TREE_OPERAND (t1, i), TREE_OPERAND (t2, i));
3790 /* Constructors for pointer, array and function types.
3791 (RECORD_TYPE, UNION_TYPE and ENUMERAL_TYPE nodes are
3792 constructed by language-dependent code, not here.) */
3794 /* Construct, lay out and return the type of pointers to TO_TYPE.
3795 If such a type has already been constructed, reuse it. */
3798 build_pointer_type (to_type)
3801 register tree t = TYPE_POINTER_TO (to_type);
3803 /* First, if we already have a type for pointers to TO_TYPE, use it. */
3808 /* We need a new one. Put this in the same obstack as TO_TYPE. */
3809 push_obstacks (TYPE_OBSTACK (to_type), TYPE_OBSTACK (to_type));
3810 t = make_node (POINTER_TYPE);
3813 TREE_TYPE (t) = to_type;
3815 /* Record this type as the pointer to TO_TYPE. */
3816 TYPE_POINTER_TO (to_type) = t;
3818 /* Lay out the type. This function has many callers that are concerned
3819 with expression-construction, and this simplifies them all.
3820 Also, it guarantees the TYPE_SIZE is in the same obstack as the type. */
3826 /* Create a type of integers to be the TYPE_DOMAIN of an ARRAY_TYPE.
3827 MAXVAL should be the maximum value in the domain
3828 (one less than the length of the array). */
3831 build_index_type (maxval)
3834 register tree itype = make_node (INTEGER_TYPE);
3836 TYPE_PRECISION (itype) = TYPE_PRECISION (sizetype);
3837 TYPE_MIN_VALUE (itype) = size_zero_node;
3839 push_obstacks (TYPE_OBSTACK (itype), TYPE_OBSTACK (itype));
3840 TYPE_MAX_VALUE (itype) = convert (sizetype, maxval);
3843 TYPE_MODE (itype) = TYPE_MODE (sizetype);
3844 TYPE_SIZE (itype) = TYPE_SIZE (sizetype);
3845 TYPE_ALIGN (itype) = TYPE_ALIGN (sizetype);
3846 if (TREE_CODE (maxval) == INTEGER_CST)
3848 int maxint = (int) TREE_INT_CST_LOW (maxval);
3849 /* If the domain should be empty, make sure the maxval
3850 remains -1 and is not spoiled by truncation. */
3851 if (INT_CST_LT (maxval, integer_zero_node))
3853 TYPE_MAX_VALUE (itype) = build_int_2 (-1, -1);
3854 TREE_TYPE (TYPE_MAX_VALUE (itype)) = sizetype;
3856 return type_hash_canon (maxint < 0 ? ~maxint : maxint, itype);
3862 /* Create a range of some discrete type TYPE (an INTEGER_TYPE,
3863 ENUMERAL_TYPE, BOOLEAN_TYPE, or CHAR_TYPE), with
3864 low bound LOWVAL and high bound HIGHVAL.
3865 if TYPE==NULL_TREE, sizetype is used. */
3868 build_range_type (type, lowval, highval)
3869 tree type, lowval, highval;
3871 register tree itype = make_node (INTEGER_TYPE);
3873 TREE_TYPE (itype) = type;
3874 if (type == NULL_TREE)
3877 push_obstacks (TYPE_OBSTACK (itype), TYPE_OBSTACK (itype));
3878 TYPE_MIN_VALUE (itype) = convert (type, lowval);
3879 TYPE_MAX_VALUE (itype) = convert (type, highval);
3882 TYPE_PRECISION (itype) = TYPE_PRECISION (type);
3883 TYPE_MODE (itype) = TYPE_MODE (type);
3884 TYPE_SIZE (itype) = TYPE_SIZE (type);
3885 TYPE_ALIGN (itype) = TYPE_ALIGN (type);
3886 if ((TREE_CODE (lowval) == INTEGER_CST)
3887 && (TREE_CODE (highval) == INTEGER_CST))
3889 HOST_WIDE_INT highint = TREE_INT_CST_LOW (highval);
3890 HOST_WIDE_INT lowint = TREE_INT_CST_LOW (lowval);
3891 int maxint = (int) (highint - lowint);
3892 return type_hash_canon (maxint < 0 ? ~maxint : maxint, itype);
3898 /* Just like build_index_type, but takes lowval and highval instead
3899 of just highval (maxval). */
3902 build_index_2_type (lowval,highval)
3903 tree lowval, highval;
3905 return build_range_type (NULL_TREE, lowval, highval);
3908 /* Return nonzero iff ITYPE1 and ITYPE2 are equal (in the LISP sense).
3909 Needed because when index types are not hashed, equal index types
3910 built at different times appear distinct, even though structurally,
3914 index_type_equal (itype1, itype2)
3915 tree itype1, itype2;
3917 if (TREE_CODE (itype1) != TREE_CODE (itype2))
3919 if (TREE_CODE (itype1) == INTEGER_TYPE)
3921 if (TYPE_PRECISION (itype1) != TYPE_PRECISION (itype2)
3922 || TYPE_MODE (itype1) != TYPE_MODE (itype2)
3923 || simple_cst_equal (TYPE_SIZE (itype1), TYPE_SIZE (itype2)) != 1
3924 || TYPE_ALIGN (itype1) != TYPE_ALIGN (itype2))
3926 if (1 == simple_cst_equal (TYPE_MIN_VALUE (itype1),
3927 TYPE_MIN_VALUE (itype2))
3928 && 1 == simple_cst_equal (TYPE_MAX_VALUE (itype1),
3929 TYPE_MAX_VALUE (itype2)))
3936 /* Construct, lay out and return the type of arrays of elements with ELT_TYPE
3937 and number of elements specified by the range of values of INDEX_TYPE.
3938 If such a type has already been constructed, reuse it. */
3941 build_array_type (elt_type, index_type)
3942 tree elt_type, index_type;
3947 if (TREE_CODE (elt_type) == FUNCTION_TYPE)
3949 error ("arrays of functions are not meaningful");
3950 elt_type = integer_type_node;
3953 /* Make sure TYPE_POINTER_TO (elt_type) is filled in. */
3954 build_pointer_type (elt_type);
3956 /* Allocate the array after the pointer type,
3957 in case we free it in type_hash_canon. */
3958 t = make_node (ARRAY_TYPE);
3959 TREE_TYPE (t) = elt_type;
3960 TYPE_DOMAIN (t) = index_type;
3962 if (index_type == 0)
3967 hashcode = TYPE_HASH (elt_type) + TYPE_HASH (index_type);
3968 t = type_hash_canon (hashcode, t);
3970 if (TYPE_SIZE (t) == 0)
3975 /* Construct, lay out and return
3976 the type of functions returning type VALUE_TYPE
3977 given arguments of types ARG_TYPES.
3978 ARG_TYPES is a chain of TREE_LIST nodes whose TREE_VALUEs
3979 are data type nodes for the arguments of the function.
3980 If such a type has already been constructed, reuse it. */
3983 build_function_type (value_type, arg_types)
3984 tree value_type, arg_types;
3989 if (TREE_CODE (value_type) == FUNCTION_TYPE)
3991 error ("function return type cannot be function");
3992 value_type = integer_type_node;
3995 /* Make a node of the sort we want. */
3996 t = make_node (FUNCTION_TYPE);
3997 TREE_TYPE (t) = value_type;
3998 TYPE_ARG_TYPES (t) = arg_types;
4000 /* If we already have such a type, use the old one and free this one. */
4001 hashcode = TYPE_HASH (value_type) + type_hash_list (arg_types);
4002 t = type_hash_canon (hashcode, t);
4004 if (TYPE_SIZE (t) == 0)
4009 /* Build the node for the type of references-to-TO_TYPE. */
4012 build_reference_type (to_type)
4015 register tree t = TYPE_REFERENCE_TO (to_type);
4016 register struct obstack *ambient_obstack = current_obstack;
4017 register struct obstack *ambient_saveable_obstack = saveable_obstack;
4019 /* First, if we already have a type for pointers to TO_TYPE, use it. */
4024 /* We need a new one. If TO_TYPE is permanent, make this permanent too. */
4025 if (TREE_PERMANENT (to_type))
4027 current_obstack = &permanent_obstack;
4028 saveable_obstack = &permanent_obstack;
4031 t = make_node (REFERENCE_TYPE);
4032 TREE_TYPE (t) = to_type;
4034 /* Record this type as the pointer to TO_TYPE. */
4035 TYPE_REFERENCE_TO (to_type) = t;
4039 current_obstack = ambient_obstack;
4040 saveable_obstack = ambient_saveable_obstack;
4044 /* Construct, lay out and return the type of methods belonging to class
4045 BASETYPE and whose arguments and values are described by TYPE.
4046 If that type exists already, reuse it.
4047 TYPE must be a FUNCTION_TYPE node. */
4050 build_method_type (basetype, type)
4051 tree basetype, type;
4056 /* Make a node of the sort we want. */
4057 t = make_node (METHOD_TYPE);
4059 if (TREE_CODE (type) != FUNCTION_TYPE)
4062 TYPE_METHOD_BASETYPE (t) = TYPE_MAIN_VARIANT (basetype);
4063 TREE_TYPE (t) = TREE_TYPE (type);
4065 /* The actual arglist for this function includes a "hidden" argument
4066 which is "this". Put it into the list of argument types. */
4069 = tree_cons (NULL_TREE,
4070 build_pointer_type (basetype), TYPE_ARG_TYPES (type));
4072 /* If we already have such a type, use the old one and free this one. */
4073 hashcode = TYPE_HASH (basetype) + TYPE_HASH (type);
4074 t = type_hash_canon (hashcode, t);
4076 if (TYPE_SIZE (t) == 0)
4082 /* Construct, lay out and return the type of offsets to a value
4083 of type TYPE, within an object of type BASETYPE.
4084 If a suitable offset type exists already, reuse it. */
4087 build_offset_type (basetype, type)
4088 tree basetype, type;
4093 /* Make a node of the sort we want. */
4094 t = make_node (OFFSET_TYPE);
4096 TYPE_OFFSET_BASETYPE (t) = TYPE_MAIN_VARIANT (basetype);
4097 TREE_TYPE (t) = type;
4099 /* If we already have such a type, use the old one and free this one. */
4100 hashcode = TYPE_HASH (basetype) + TYPE_HASH (type);
4101 t = type_hash_canon (hashcode, t);
4103 if (TYPE_SIZE (t) == 0)
4109 /* Create a complex type whose components are COMPONENT_TYPE. */
4112 build_complex_type (component_type)
4113 tree component_type;
4118 /* Make a node of the sort we want. */
4119 t = make_node (COMPLEX_TYPE);
4121 TREE_TYPE (t) = TYPE_MAIN_VARIANT (component_type);
4122 TYPE_VOLATILE (t) = TYPE_VOLATILE (component_type);
4123 TYPE_READONLY (t) = TYPE_READONLY (component_type);
4125 /* If we already have such a type, use the old one and free this one. */
4126 hashcode = TYPE_HASH (component_type);
4127 t = type_hash_canon (hashcode, t);
4129 if (TYPE_SIZE (t) == 0)
4135 /* Return OP, stripped of any conversions to wider types as much as is safe.
4136 Converting the value back to OP's type makes a value equivalent to OP.
4138 If FOR_TYPE is nonzero, we return a value which, if converted to
4139 type FOR_TYPE, would be equivalent to converting OP to type FOR_TYPE.
4141 If FOR_TYPE is nonzero, unaligned bit-field references may be changed to the
4142 narrowest type that can hold the value, even if they don't exactly fit.
4143 Otherwise, bit-field references are changed to a narrower type
4144 only if they can be fetched directly from memory in that type.
4146 OP must have integer, real or enumeral type. Pointers are not allowed!
4148 There are some cases where the obvious value we could return
4149 would regenerate to OP if converted to OP's type,
4150 but would not extend like OP to wider types.
4151 If FOR_TYPE indicates such extension is contemplated, we eschew such values.
4152 For example, if OP is (unsigned short)(signed char)-1,
4153 we avoid returning (signed char)-1 if FOR_TYPE is int,
4154 even though extending that to an unsigned short would regenerate OP,
4155 since the result of extending (signed char)-1 to (int)
4156 is different from (int) OP. */
4159 get_unwidened (op, for_type)
4163 /* Set UNS initially if converting OP to FOR_TYPE is a zero-extension. */
4164 /* TYPE_PRECISION is safe in place of type_precision since
4165 pointer types are not allowed. */
4166 register tree type = TREE_TYPE (op);
4167 register unsigned final_prec
4168 = TYPE_PRECISION (for_type != 0 ? for_type : type);
4170 = (for_type != 0 && for_type != type
4171 && final_prec > TYPE_PRECISION (type)
4172 && TREE_UNSIGNED (type));
4173 register tree win = op;
4175 while (TREE_CODE (op) == NOP_EXPR)
4177 register int bitschange
4178 = TYPE_PRECISION (TREE_TYPE (op))
4179 - TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (op, 0)));
4181 /* Truncations are many-one so cannot be removed.
4182 Unless we are later going to truncate down even farther. */
4184 && final_prec > TYPE_PRECISION (TREE_TYPE (op)))
4187 /* See what's inside this conversion. If we decide to strip it,
4189 op = TREE_OPERAND (op, 0);
4191 /* If we have not stripped any zero-extensions (uns is 0),
4192 we can strip any kind of extension.
4193 If we have previously stripped a zero-extension,
4194 only zero-extensions can safely be stripped.
4195 Any extension can be stripped if the bits it would produce
4196 are all going to be discarded later by truncating to FOR_TYPE. */
4200 if (! uns || final_prec <= TYPE_PRECISION (TREE_TYPE (op)))
4202 /* TREE_UNSIGNED says whether this is a zero-extension.
4203 Let's avoid computing it if it does not affect WIN
4204 and if UNS will not be needed again. */
4205 if ((uns || TREE_CODE (op) == NOP_EXPR)
4206 && TREE_UNSIGNED (TREE_TYPE (op)))
4214 if (TREE_CODE (op) == COMPONENT_REF
4215 /* Since type_for_size always gives an integer type. */
4216 && TREE_CODE (type) != REAL_TYPE
4217 /* Don't crash if field not layed out yet. */
4218 && DECL_SIZE (TREE_OPERAND (op, 1)) != 0)
4220 unsigned innerprec = TREE_INT_CST_LOW (DECL_SIZE (TREE_OPERAND (op, 1)));
4221 type = type_for_size (innerprec, TREE_UNSIGNED (TREE_OPERAND (op, 1)));
4223 /* We can get this structure field in the narrowest type it fits in.
4224 If FOR_TYPE is 0, do this only for a field that matches the
4225 narrower type exactly and is aligned for it
4226 The resulting extension to its nominal type (a fullword type)
4227 must fit the same conditions as for other extensions. */
4229 if (innerprec < TYPE_PRECISION (TREE_TYPE (op))
4230 && (for_type || ! DECL_BIT_FIELD (TREE_OPERAND (op, 1)))
4231 && (! uns || final_prec <= innerprec
4232 || TREE_UNSIGNED (TREE_OPERAND (op, 1)))
4235 win = build (COMPONENT_REF, type, TREE_OPERAND (op, 0),
4236 TREE_OPERAND (op, 1));
4237 TREE_SIDE_EFFECTS (win) = TREE_SIDE_EFFECTS (op);
4238 TREE_THIS_VOLATILE (win) = TREE_THIS_VOLATILE (op);
4239 TREE_RAISES (win) = TREE_RAISES (op);
4245 /* Return OP or a simpler expression for a narrower value
4246 which can be sign-extended or zero-extended to give back OP.
4247 Store in *UNSIGNEDP_PTR either 1 if the value should be zero-extended
4248 or 0 if the value should be sign-extended. */
4251 get_narrower (op, unsignedp_ptr)
4255 register int uns = 0;
4257 register tree win = op;
4259 while (TREE_CODE (op) == NOP_EXPR)
4261 register int bitschange
4262 = TYPE_PRECISION (TREE_TYPE (op))
4263 - TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (op, 0)));
4265 /* Truncations are many-one so cannot be removed. */
4269 /* See what's inside this conversion. If we decide to strip it,
4271 op = TREE_OPERAND (op, 0);
4275 /* An extension: the outermost one can be stripped,
4276 but remember whether it is zero or sign extension. */
4278 uns = TREE_UNSIGNED (TREE_TYPE (op));
4279 /* Otherwise, if a sign extension has been stripped,
4280 only sign extensions can now be stripped;
4281 if a zero extension has been stripped, only zero-extensions. */
4282 else if (uns != TREE_UNSIGNED (TREE_TYPE (op)))
4286 else /* bitschange == 0 */
4288 /* A change in nominal type can always be stripped, but we must
4289 preserve the unsignedness. */
4291 uns = TREE_UNSIGNED (TREE_TYPE (op));
4298 if (TREE_CODE (op) == COMPONENT_REF
4299 /* Since type_for_size always gives an integer type. */
4300 && TREE_CODE (TREE_TYPE (op)) != REAL_TYPE)
4302 unsigned innerprec = TREE_INT_CST_LOW (DECL_SIZE (TREE_OPERAND (op, 1)));
4303 tree type = type_for_size (innerprec, TREE_UNSIGNED (op));
4305 /* We can get this structure field in a narrower type that fits it,
4306 but the resulting extension to its nominal type (a fullword type)
4307 must satisfy the same conditions as for other extensions.
4309 Do this only for fields that are aligned (not bit-fields),
4310 because when bit-field insns will be used there is no
4311 advantage in doing this. */
4313 if (innerprec < TYPE_PRECISION (TREE_TYPE (op))
4314 && ! DECL_BIT_FIELD (TREE_OPERAND (op, 1))
4315 && (first || uns == TREE_UNSIGNED (TREE_OPERAND (op, 1)))
4319 uns = TREE_UNSIGNED (TREE_OPERAND (op, 1));
4320 win = build (COMPONENT_REF, type, TREE_OPERAND (op, 0),
4321 TREE_OPERAND (op, 1));
4322 TREE_SIDE_EFFECTS (win) = TREE_SIDE_EFFECTS (op);
4323 TREE_THIS_VOLATILE (win) = TREE_THIS_VOLATILE (op);
4324 TREE_RAISES (win) = TREE_RAISES (op);
4327 *unsignedp_ptr = uns;
4331 /* Return the precision of a type, for arithmetic purposes.
4332 Supports all types on which arithmetic is possible
4333 (including pointer types).
4334 It's not clear yet what will be right for complex types. */
4337 type_precision (type)
4340 return ((TREE_CODE (type) == INTEGER_TYPE
4341 || TREE_CODE (type) == ENUMERAL_TYPE
4342 || TREE_CODE (type) == REAL_TYPE)
4343 ? TYPE_PRECISION (type) : POINTER_SIZE);
4346 /* Nonzero if integer constant C has a value that is permissible
4347 for type TYPE (an INTEGER_TYPE). */
4350 int_fits_type_p (c, type)
4353 if (TREE_UNSIGNED (type))
4354 return (! (TREE_CODE (TYPE_MAX_VALUE (type)) == INTEGER_CST
4355 && INT_CST_LT_UNSIGNED (TYPE_MAX_VALUE (type), c))
4356 && ! (TREE_CODE (TYPE_MIN_VALUE (type)) == INTEGER_CST
4357 && INT_CST_LT_UNSIGNED (c, TYPE_MIN_VALUE (type)))
4358 /* Negative ints never fit unsigned types. */
4359 && ! (TREE_INT_CST_HIGH (c) < 0
4360 && ! TREE_UNSIGNED (TREE_TYPE (c))));
4362 return (! (TREE_CODE (TYPE_MAX_VALUE (type)) == INTEGER_CST
4363 && INT_CST_LT (TYPE_MAX_VALUE (type), c))
4364 && ! (TREE_CODE (TYPE_MIN_VALUE (type)) == INTEGER_CST
4365 && INT_CST_LT (c, TYPE_MIN_VALUE (type)))
4366 /* Unsigned ints with top bit set never fit signed types. */
4367 && ! (TREE_INT_CST_HIGH (c) < 0
4368 && TREE_UNSIGNED (TREE_TYPE (c))));
4371 /* Return the innermost context enclosing DECL that is
4372 a FUNCTION_DECL, or zero if none. */
4375 decl_function_context (decl)
4380 if (TREE_CODE (decl) == ERROR_MARK)
4383 if (TREE_CODE (decl) == SAVE_EXPR)
4384 context = SAVE_EXPR_CONTEXT (decl);
4386 context = DECL_CONTEXT (decl);
4388 while (context && TREE_CODE (context) != FUNCTION_DECL)
4390 if (TREE_CODE (context) == RECORD_TYPE
4391 || TREE_CODE (context) == UNION_TYPE
4392 || TREE_CODE (context) == QUAL_UNION_TYPE)
4393 context = TYPE_CONTEXT (context);
4394 else if (TREE_CODE (context) == TYPE_DECL)
4395 context = DECL_CONTEXT (context);
4396 else if (TREE_CODE (context) == BLOCK)
4397 context = BLOCK_SUPERCONTEXT (context);
4399 /* Unhandled CONTEXT !? */
4406 /* Return the innermost context enclosing DECL that is
4407 a RECORD_TYPE, UNION_TYPE or QUAL_UNION_TYPE, or zero if none.
4408 TYPE_DECLs and FUNCTION_DECLs are transparent to this function. */
4411 decl_type_context (decl)
4414 tree context = DECL_CONTEXT (decl);
4418 if (TREE_CODE (context) == RECORD_TYPE
4419 || TREE_CODE (context) == UNION_TYPE
4420 || TREE_CODE (context) == QUAL_UNION_TYPE)
4422 if (TREE_CODE (context) == TYPE_DECL
4423 || TREE_CODE (context) == FUNCTION_DECL)
4424 context = DECL_CONTEXT (context);
4425 else if (TREE_CODE (context) == BLOCK)
4426 context = BLOCK_SUPERCONTEXT (context);
4428 /* Unhandled CONTEXT!? */
4435 print_obstack_statistics (str, o)
4439 struct _obstack_chunk *chunk = o->chunk;
4446 n_alloc += chunk->limit - &chunk->contents[0];
4447 chunk = chunk->prev;
4449 fprintf (stderr, "obstack %s: %d bytes, %d chunks\n",
4450 str, n_alloc, n_chunks);
4453 dump_tree_statistics ()
4456 int total_nodes, total_bytes;
4458 fprintf (stderr, "\n??? tree nodes created\n\n");
4459 #ifdef GATHER_STATISTICS
4460 fprintf (stderr, "Kind Nodes Bytes\n");
4461 fprintf (stderr, "-------------------------------------\n");
4462 total_nodes = total_bytes = 0;
4463 for (i = 0; i < (int) all_kinds; i++)
4465 fprintf (stderr, "%-20s %6d %9d\n", tree_node_kind_names[i],
4466 tree_node_counts[i], tree_node_sizes[i]);
4467 total_nodes += tree_node_counts[i];
4468 total_bytes += tree_node_sizes[i];
4470 fprintf (stderr, "%-20s %9d\n", "identifier names", id_string_size);
4471 fprintf (stderr, "-------------------------------------\n");
4472 fprintf (stderr, "%-20s %6d %9d\n", "Total", total_nodes, total_bytes);
4473 fprintf (stderr, "-------------------------------------\n");
4475 fprintf (stderr, "(No per-node statistics)\n");
4477 print_lang_statistics ();
4480 #define FILE_FUNCTION_PREFIX_LEN 9
4482 #ifndef NO_DOLLAR_IN_LABEL
4483 #define FILE_FUNCTION_FORMAT "_GLOBAL_$D$%s"
4484 #else /* NO_DOLLAR_IN_LABEL */
4485 #ifndef NO_DOT_IN_LABEL
4486 #define FILE_FUNCTION_FORMAT "_GLOBAL_.D.%s"
4487 #else /* NO_DOT_IN_LABEL */
4488 #define FILE_FUNCTION_FORMAT "_GLOBAL__D_%s"
4489 #endif /* NO_DOT_IN_LABEL */
4490 #endif /* NO_DOLLAR_IN_LABEL */
4492 extern char * first_global_object_name;
4494 /* If KIND=='I', return a suitable global initializer (constructor) name.
4495 If KIND=='D', return a suitable global clean-up (destructor) name. */
4498 get_file_function_name (kind)
4504 if (first_global_object_name)
4505 p = first_global_object_name;
4506 else if (main_input_filename)
4507 p = main_input_filename;
4511 buf = (char *) alloca (sizeof (FILE_FUNCTION_FORMAT) + strlen (p));
4513 /* Set up the name of the file-level functions we may need. */
4514 /* Use a global object (which is already required to be unique over
4515 the program) rather than the file name (which imposes extra
4516 constraints). -- Raeburn@MIT.EDU, 10 Jan 1990. */
4517 sprintf (buf, FILE_FUNCTION_FORMAT, p);
4519 /* Don't need to pull weird characters out of global names. */
4520 if (p != first_global_object_name)
4522 for (p = buf+11; *p; p++)
4523 if (! ((*p >= '0' && *p <= '9')
4524 #if 0 /* we always want labels, which are valid C++ identifiers (+ `$') */
4525 #ifndef ASM_IDENTIFY_GCC /* this is required if `.' is invalid -- k. raeburn */
4529 #ifndef NO_DOLLAR_IN_LABEL /* this for `$'; unlikely, but... -- kr */
4532 #ifndef NO_DOT_IN_LABEL /* this for `.'; unlikely, but... */
4535 || (*p >= 'A' && *p <= 'Z')
4536 || (*p >= 'a' && *p <= 'z')))
4540 buf[FILE_FUNCTION_PREFIX_LEN] = kind;
4542 return get_identifier (buf);
4545 /* Expand (the constant part of) a SET_TYPE CONSTRUCTOR node.
4546 The result is placed in BUFFER (which has length BIT_SIZE),
4547 with one bit in each char ('\000' or '\001').
4549 If the constructor is constant, NULL_TREE is returned.
4550 Otherwise, a TREE_LIST of the non-constant elements is emitted. */
4553 get_set_constructor_bits (init, buffer, bit_size)
4560 HOST_WIDE_INT domain_min
4561 = TREE_INT_CST_LOW (TYPE_MIN_VALUE (TYPE_DOMAIN (TREE_TYPE (init))));
4562 tree non_const_bits = NULL_TREE;
4563 for (i = 0; i < bit_size; i++)
4566 for (vals = TREE_OPERAND (init, 1);
4567 vals != NULL_TREE; vals = TREE_CHAIN (vals))
4569 if (TREE_CODE (TREE_VALUE (vals)) != INTEGER_CST
4570 || (TREE_PURPOSE (vals) != NULL_TREE
4571 && TREE_CODE (TREE_PURPOSE (vals)) != INTEGER_CST))
4573 = tree_cons (TREE_PURPOSE (vals), TREE_VALUE (vals), non_const_bits);
4574 else if (TREE_PURPOSE (vals) != NULL_TREE)
4576 /* Set a range of bits to ones. */
4577 HOST_WIDE_INT lo_index
4578 = TREE_INT_CST_LOW (TREE_PURPOSE (vals)) - domain_min;
4579 HOST_WIDE_INT hi_index
4580 = TREE_INT_CST_LOW (TREE_VALUE (vals)) - domain_min;
4581 if (lo_index < 0 || lo_index >= bit_size
4582 || hi_index < 0 || hi_index >= bit_size)
4584 for ( ; lo_index <= hi_index; lo_index++)
4585 buffer[lo_index] = 1;
4589 /* Set a single bit to one. */
4591 = TREE_INT_CST_LOW (TREE_VALUE (vals)) - domain_min;
4592 if (index < 0 || index >= bit_size)
4594 error ("invalid initializer for bit string");
4600 return non_const_bits;
4603 /* Expand (the constant part of) a SET_TYPE CONSTRUCTOR node.
4604 The result is placed in BUFFER (which is an array of bytes).
4605 If the constructor is constant, NULL_TREE is returned.
4606 Otherwise, a TREE_LIST of the non-constant elements is emitted. */
4609 get_set_constructor_bytes (init, buffer, wd_size)
4611 unsigned char *buffer;
4615 tree vals = TREE_OPERAND (init, 1);
4616 int set_word_size = BITS_PER_UNIT;
4617 int bit_size = wd_size * set_word_size;
4619 unsigned char *bytep = buffer;
4620 char *bit_buffer = (char *) alloca(bit_size);
4621 tree non_const_bits = get_set_constructor_bits (init, bit_buffer, bit_size);
4623 for (i = 0; i < wd_size; i++)
4626 for (i = 0; i < bit_size; i++)
4630 if (BYTES_BIG_ENDIAN)
4631 *bytep |= (1 << (set_word_size - 1 - bit_pos));
4633 *bytep |= 1 << bit_pos;
4636 if (bit_pos >= set_word_size)
4637 bit_pos = 0, bytep++;
4639 return non_const_bits;