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 *));
62 #define obstack_chunk_alloc xmalloc
63 #define obstack_chunk_free free
65 /* Tree nodes of permanent duration are allocated in this obstack.
66 They are the identifier nodes, and everything outside of
67 the bodies and parameters of function definitions. */
69 struct obstack permanent_obstack;
71 /* The initial RTL, and all ..._TYPE nodes, in a function
72 are allocated in this obstack. Usually they are freed at the
73 end of the function, but if the function is inline they are saved.
74 For top-level functions, this is maybepermanent_obstack.
75 Separate obstacks are made for nested functions. */
77 struct obstack *function_maybepermanent_obstack;
79 /* This is the function_maybepermanent_obstack for top-level functions. */
81 struct obstack maybepermanent_obstack;
83 /* This is a list of function_maybepermanent_obstacks for top-level inline
84 functions that are compiled in the middle of compiling other functions. */
86 struct simple_obstack_stack *toplev_inline_obstacks;
88 /* Former elements of toplev_inline_obstacks that have been recycled. */
90 struct simple_obstack_stack *extra_inline_obstacks;
92 /* This is a list of function_maybepermanent_obstacks for inline functions
93 nested in the current function that were compiled in the middle of
94 compiling other functions. */
96 struct simple_obstack_stack *inline_obstacks;
98 /* The contents of the current function definition are allocated
99 in this obstack, and all are freed at the end of the function.
100 For top-level functions, this is temporary_obstack.
101 Separate obstacks are made for nested functions. */
103 struct obstack *function_obstack;
105 /* This is used for reading initializers of global variables. */
107 struct obstack temporary_obstack;
109 /* The tree nodes of an expression are allocated
110 in this obstack, and all are freed at the end of the expression. */
112 struct obstack momentary_obstack;
114 /* The tree nodes of a declarator are allocated
115 in this obstack, and all are freed when the declarator
118 static struct obstack temp_decl_obstack;
120 /* This points at either permanent_obstack
121 or the current function_maybepermanent_obstack. */
123 struct obstack *saveable_obstack;
125 /* This is same as saveable_obstack during parse and expansion phase;
126 it points to the current function's obstack during optimization.
127 This is the obstack to be used for creating rtl objects. */
129 struct obstack *rtl_obstack;
131 /* This points at either permanent_obstack or the current function_obstack. */
133 struct obstack *current_obstack;
135 /* This points at either permanent_obstack or the current function_obstack
136 or momentary_obstack. */
138 struct obstack *expression_obstack;
140 /* Stack of obstack selections for push_obstacks and pop_obstacks. */
144 struct obstack_stack *next;
145 struct obstack *current;
146 struct obstack *saveable;
147 struct obstack *expression;
151 struct obstack_stack *obstack_stack;
153 /* Obstack for allocating struct obstack_stack entries. */
155 static struct obstack obstack_stack_obstack;
157 /* Addresses of first objects in some obstacks.
158 This is for freeing their entire contents. */
159 char *maybepermanent_firstobj;
160 char *temporary_firstobj;
161 char *momentary_firstobj;
162 char *temp_decl_firstobj;
164 /* This is used to preserve objects (mainly array initializers) that need to
165 live until the end of the current function, but no further. */
166 char *momentary_function_firstobj;
168 /* Nonzero means all ..._TYPE nodes should be allocated permanently. */
170 int all_types_permanent;
172 /* Stack of places to restore the momentary obstack back to. */
174 struct momentary_level
176 /* Pointer back to previous such level. */
177 struct momentary_level *prev;
178 /* First object allocated within this level. */
180 /* Value of expression_obstack saved at entry to this level. */
181 struct obstack *obstack;
184 struct momentary_level *momentary_stack;
186 /* Table indexed by tree code giving a string containing a character
187 classifying the tree code. Possibilities are
188 t, d, s, c, r, <, 1, 2 and e. See tree.def for details. */
190 #define DEFTREECODE(SYM, NAME, TYPE, LENGTH) TYPE,
192 char *standard_tree_code_type[] = {
197 /* Table indexed by tree code giving number of expression
198 operands beyond the fixed part of the node structure.
199 Not used for types or decls. */
201 #define DEFTREECODE(SYM, NAME, TYPE, LENGTH) LENGTH,
203 int standard_tree_code_length[] = {
208 /* Names of tree components.
209 Used for printing out the tree and error messages. */
210 #define DEFTREECODE(SYM, NAME, TYPE, LEN) NAME,
212 char *standard_tree_code_name[] = {
217 /* Table indexed by tree code giving a string containing a character
218 classifying the tree code. Possibilities are
219 t, d, s, c, r, e, <, 1 and 2. See tree.def for details. */
221 char **tree_code_type;
223 /* Table indexed by tree code giving number of expression
224 operands beyond the fixed part of the node structure.
225 Not used for types or decls. */
227 int *tree_code_length;
229 /* Table indexed by tree code giving name of tree code, as a string. */
231 char **tree_code_name;
233 /* Statistics-gathering stuff. */
254 int tree_node_counts[(int)all_kinds];
255 int tree_node_sizes[(int)all_kinds];
256 int id_string_size = 0;
258 char *tree_node_kind_names[] = {
276 /* Hash table for uniquizing IDENTIFIER_NODEs by name. */
278 #define MAX_HASH_TABLE 1009
279 static tree hash_table[MAX_HASH_TABLE]; /* id hash buckets */
281 /* 0 while creating built-in identifiers. */
282 static int do_identifier_warnings;
284 /* Unique id for next decl created. */
285 static int next_decl_uid;
286 /* Unique id for next type created. */
287 static int next_type_uid = 1;
289 /* Here is how primitive or already-canonicalized types' hash
291 #define TYPE_HASH(TYPE) ((HOST_WIDE_INT) (TYPE) & 0777777)
293 extern char *mode_name[];
295 void gcc_obstack_init ();
297 /* Init the principal obstacks. */
302 gcc_obstack_init (&obstack_stack_obstack);
303 gcc_obstack_init (&permanent_obstack);
305 gcc_obstack_init (&temporary_obstack);
306 temporary_firstobj = (char *) obstack_alloc (&temporary_obstack, 0);
307 gcc_obstack_init (&momentary_obstack);
308 momentary_firstobj = (char *) obstack_alloc (&momentary_obstack, 0);
309 momentary_function_firstobj = momentary_firstobj;
310 gcc_obstack_init (&maybepermanent_obstack);
311 maybepermanent_firstobj
312 = (char *) obstack_alloc (&maybepermanent_obstack, 0);
313 gcc_obstack_init (&temp_decl_obstack);
314 temp_decl_firstobj = (char *) obstack_alloc (&temp_decl_obstack, 0);
316 function_obstack = &temporary_obstack;
317 function_maybepermanent_obstack = &maybepermanent_obstack;
318 current_obstack = &permanent_obstack;
319 expression_obstack = &permanent_obstack;
320 rtl_obstack = saveable_obstack = &permanent_obstack;
322 /* Init the hash table of identifiers. */
323 bzero ((char *) hash_table, sizeof hash_table);
327 gcc_obstack_init (obstack)
328 struct obstack *obstack;
330 /* Let particular systems override the size of a chunk. */
331 #ifndef OBSTACK_CHUNK_SIZE
332 #define OBSTACK_CHUNK_SIZE 0
334 /* Let them override the alloc and free routines too. */
335 #ifndef OBSTACK_CHUNK_ALLOC
336 #define OBSTACK_CHUNK_ALLOC xmalloc
338 #ifndef OBSTACK_CHUNK_FREE
339 #define OBSTACK_CHUNK_FREE free
341 _obstack_begin (obstack, OBSTACK_CHUNK_SIZE, 0,
342 (void *(*) ()) OBSTACK_CHUNK_ALLOC,
343 (void (*) ()) OBSTACK_CHUNK_FREE);
346 /* Save all variables describing the current status into the structure *P.
347 This is used before starting a nested function.
349 CONTEXT is the decl_function_context for the function we're about to
350 compile; if it isn't current_function_decl, we have to play some games. */
353 save_tree_status (p, context)
357 p->all_types_permanent = all_types_permanent;
358 p->momentary_stack = momentary_stack;
359 p->maybepermanent_firstobj = maybepermanent_firstobj;
360 p->temporary_firstobj = temporary_firstobj;
361 p->momentary_firstobj = momentary_firstobj;
362 p->momentary_function_firstobj = momentary_function_firstobj;
363 p->function_obstack = function_obstack;
364 p->function_maybepermanent_obstack = function_maybepermanent_obstack;
365 p->current_obstack = current_obstack;
366 p->expression_obstack = expression_obstack;
367 p->saveable_obstack = saveable_obstack;
368 p->rtl_obstack = rtl_obstack;
369 p->inline_obstacks = inline_obstacks;
371 if (context == current_function_decl)
372 /* Objects that need to be saved in this function can be in the nonsaved
373 obstack of the enclosing function since they can't possibly be needed
374 once it has returned. */
375 function_maybepermanent_obstack = function_obstack;
378 /* We're compiling a function which isn't nested in the current
379 function. We need to create a new maybepermanent_obstack for this
380 function, since it can't go onto any of the existing obstacks. */
381 struct simple_obstack_stack **head;
382 struct simple_obstack_stack *current;
384 if (context == NULL_TREE)
385 head = &toplev_inline_obstacks;
388 struct function *f = find_function_data (context);
389 head = &f->inline_obstacks;
392 if (context == NULL_TREE && extra_inline_obstacks)
394 current = extra_inline_obstacks;
395 extra_inline_obstacks = current->next;
399 current = ((struct simple_obstack_stack *)
400 xmalloc (sizeof (struct simple_obstack_stack)));
403 = (struct obstack *) xmalloc (sizeof (struct obstack));
404 gcc_obstack_init (current->obstack);
407 function_maybepermanent_obstack = current->obstack;
409 current->next = *head;
413 maybepermanent_firstobj
414 = (char *) obstack_finish (function_maybepermanent_obstack);
416 function_obstack = (struct obstack *) xmalloc (sizeof (struct obstack));
417 gcc_obstack_init (function_obstack);
419 current_obstack = &permanent_obstack;
420 expression_obstack = &permanent_obstack;
421 rtl_obstack = saveable_obstack = &permanent_obstack;
423 temporary_firstobj = (char *) obstack_alloc (&temporary_obstack, 0);
424 momentary_firstobj = (char *) obstack_finish (&momentary_obstack);
425 momentary_function_firstobj = momentary_firstobj;
428 /* Restore all variables describing the current status from the structure *P.
429 This is used after a nested function. */
432 restore_tree_status (p, context)
436 all_types_permanent = p->all_types_permanent;
437 momentary_stack = p->momentary_stack;
439 obstack_free (&momentary_obstack, momentary_function_firstobj);
441 /* Free saveable storage used by the function just compiled and not
444 CAUTION: This is in function_obstack of the containing function.
445 So we must be sure that we never allocate from that obstack during
446 the compilation of a nested function if we expect it to survive
447 past the nested function's end. */
448 obstack_free (function_maybepermanent_obstack, maybepermanent_firstobj);
450 /* If we were compiling a toplevel function, we can free this space now. */
451 if (context == NULL_TREE)
453 obstack_free (&temporary_obstack, temporary_firstobj);
454 obstack_free (&momentary_obstack, momentary_function_firstobj);
457 /* If we were compiling a toplevel function that we don't actually want
458 to save anything from, return the obstack to the pool. */
459 if (context == NULL_TREE
460 && obstack_empty_p (function_maybepermanent_obstack))
462 struct simple_obstack_stack *current, **p = &toplev_inline_obstacks;
464 while ((*p)->obstack != function_maybepermanent_obstack)
469 current->next = extra_inline_obstacks;
470 extra_inline_obstacks = current;
473 obstack_free (function_obstack, 0);
474 free (function_obstack);
476 temporary_firstobj = p->temporary_firstobj;
477 momentary_firstobj = p->momentary_firstobj;
478 momentary_function_firstobj = p->momentary_function_firstobj;
479 maybepermanent_firstobj = p->maybepermanent_firstobj;
480 function_obstack = p->function_obstack;
481 function_maybepermanent_obstack = p->function_maybepermanent_obstack;
482 current_obstack = p->current_obstack;
483 expression_obstack = p->expression_obstack;
484 saveable_obstack = p->saveable_obstack;
485 rtl_obstack = p->rtl_obstack;
486 inline_obstacks = p->inline_obstacks;
489 /* Start allocating on the temporary (per function) obstack.
490 This is done in start_function before parsing the function body,
491 and before each initialization at top level, and to go back
492 to temporary allocation after doing permanent_allocation. */
495 temporary_allocation ()
497 /* Note that function_obstack at top level points to temporary_obstack.
498 But within a nested function context, it is a separate obstack. */
499 current_obstack = function_obstack;
500 expression_obstack = function_obstack;
501 rtl_obstack = saveable_obstack = function_maybepermanent_obstack;
506 /* Start allocating on the permanent obstack but don't
507 free the temporary data. After calling this, call
508 `permanent_allocation' to fully resume permanent allocation status. */
511 end_temporary_allocation ()
513 current_obstack = &permanent_obstack;
514 expression_obstack = &permanent_obstack;
515 rtl_obstack = saveable_obstack = &permanent_obstack;
518 /* Resume allocating on the temporary obstack, undoing
519 effects of `end_temporary_allocation'. */
522 resume_temporary_allocation ()
524 current_obstack = function_obstack;
525 expression_obstack = function_obstack;
526 rtl_obstack = saveable_obstack = function_maybepermanent_obstack;
529 /* While doing temporary allocation, switch to allocating in such a
530 way as to save all nodes if the function is inlined. Call
531 resume_temporary_allocation to go back to ordinary temporary
535 saveable_allocation ()
537 /* Note that function_obstack at top level points to temporary_obstack.
538 But within a nested function context, it is a separate obstack. */
539 expression_obstack = current_obstack = saveable_obstack;
542 /* Switch to current obstack CURRENT and maybepermanent obstack SAVEABLE,
543 recording the previously current obstacks on a stack.
544 This does not free any storage in any obstack. */
547 push_obstacks (current, saveable)
548 struct obstack *current, *saveable;
550 struct obstack_stack *p
551 = (struct obstack_stack *) obstack_alloc (&obstack_stack_obstack,
552 (sizeof (struct obstack_stack)));
554 p->current = current_obstack;
555 p->saveable = saveable_obstack;
556 p->expression = expression_obstack;
557 p->rtl = rtl_obstack;
558 p->next = obstack_stack;
561 current_obstack = current;
562 expression_obstack = current;
563 rtl_obstack = saveable_obstack = saveable;
566 /* Save the current set of obstacks, but don't change them. */
569 push_obstacks_nochange ()
571 struct obstack_stack *p
572 = (struct obstack_stack *) obstack_alloc (&obstack_stack_obstack,
573 (sizeof (struct obstack_stack)));
575 p->current = current_obstack;
576 p->saveable = saveable_obstack;
577 p->expression = expression_obstack;
578 p->rtl = rtl_obstack;
579 p->next = obstack_stack;
583 /* Pop the obstack selection stack. */
588 struct obstack_stack *p = obstack_stack;
589 obstack_stack = p->next;
591 current_obstack = p->current;
592 saveable_obstack = p->saveable;
593 expression_obstack = p->expression;
594 rtl_obstack = p->rtl;
596 obstack_free (&obstack_stack_obstack, p);
599 /* Nonzero if temporary allocation is currently in effect.
600 Zero if currently doing permanent allocation. */
603 allocation_temporary_p ()
605 return current_obstack != &permanent_obstack;
608 /* Go back to allocating on the permanent obstack
609 and free everything in the temporary obstack.
611 FUNCTION_END is true only if we have just finished compiling a function.
612 In that case, we also free preserved initial values on the momentary
616 permanent_allocation (function_end)
619 /* Free up previous temporary obstack data */
620 obstack_free (&temporary_obstack, temporary_firstobj);
623 obstack_free (&momentary_obstack, momentary_function_firstobj);
624 momentary_firstobj = momentary_function_firstobj;
627 obstack_free (&momentary_obstack, momentary_firstobj);
628 obstack_free (function_maybepermanent_obstack, maybepermanent_firstobj);
629 obstack_free (&temp_decl_obstack, temp_decl_firstobj);
631 /* Free up the maybepermanent_obstacks for any of our nested functions
632 which were compiled at a lower level. */
633 while (inline_obstacks)
635 struct simple_obstack_stack *current = inline_obstacks;
636 inline_obstacks = current->next;
637 obstack_free (current->obstack, 0);
638 free (current->obstack);
642 current_obstack = &permanent_obstack;
643 expression_obstack = &permanent_obstack;
644 rtl_obstack = saveable_obstack = &permanent_obstack;
647 /* Save permanently everything on the maybepermanent_obstack. */
652 maybepermanent_firstobj
653 = (char *) obstack_alloc (function_maybepermanent_obstack, 0);
657 preserve_initializer ()
659 struct momentary_level *tem;
663 = (char *) obstack_alloc (&temporary_obstack, 0);
664 maybepermanent_firstobj
665 = (char *) obstack_alloc (function_maybepermanent_obstack, 0);
667 old_momentary = momentary_firstobj;
669 = (char *) obstack_alloc (&momentary_obstack, 0);
670 if (momentary_firstobj != old_momentary)
671 for (tem = momentary_stack; tem; tem = tem->prev)
672 tem->base = momentary_firstobj;
675 /* Start allocating new rtl in current_obstack.
676 Use resume_temporary_allocation
677 to go back to allocating rtl in saveable_obstack. */
680 rtl_in_current_obstack ()
682 rtl_obstack = current_obstack;
685 /* Start allocating rtl from saveable_obstack. Intended to be used after
686 a call to push_obstacks_nochange. */
689 rtl_in_saveable_obstack ()
691 rtl_obstack = saveable_obstack;
694 /* Allocate SIZE bytes in the current obstack
695 and return a pointer to them.
696 In practice the current obstack is always the temporary one. */
702 return (char *) obstack_alloc (current_obstack, size);
705 /* Free the object PTR in the current obstack
706 as well as everything allocated since PTR.
707 In practice the current obstack is always the temporary one. */
713 obstack_free (current_obstack, ptr);
716 /* Allocate SIZE bytes in the permanent obstack
717 and return a pointer to them. */
723 return (char *) obstack_alloc (&permanent_obstack, size);
726 /* Allocate NELEM items of SIZE bytes in the permanent obstack
727 and return a pointer to them. The storage is cleared before
728 returning the value. */
731 perm_calloc (nelem, size)
735 char *rval = (char *) obstack_alloc (&permanent_obstack, nelem * size);
736 bzero (rval, nelem * size);
740 /* Allocate SIZE bytes in the saveable obstack
741 and return a pointer to them. */
747 return (char *) obstack_alloc (saveable_obstack, size);
750 /* Allocate SIZE bytes in the expression obstack
751 and return a pointer to them. */
757 return (char *) obstack_alloc (expression_obstack, size);
760 /* Print out which obstack an object is in. */
763 print_obstack_name (object, file, prefix)
768 struct obstack *obstack = NULL;
769 char *obstack_name = NULL;
772 for (p = outer_function_chain; p; p = p->next)
774 if (_obstack_allocated_p (p->function_obstack, object))
776 obstack = p->function_obstack;
777 obstack_name = "containing function obstack";
779 if (_obstack_allocated_p (p->function_maybepermanent_obstack, object))
781 obstack = p->function_maybepermanent_obstack;
782 obstack_name = "containing function maybepermanent obstack";
786 if (_obstack_allocated_p (&obstack_stack_obstack, object))
788 obstack = &obstack_stack_obstack;
789 obstack_name = "obstack_stack_obstack";
791 else if (_obstack_allocated_p (function_obstack, object))
793 obstack = function_obstack;
794 obstack_name = "function obstack";
796 else if (_obstack_allocated_p (&permanent_obstack, object))
798 obstack = &permanent_obstack;
799 obstack_name = "permanent_obstack";
801 else if (_obstack_allocated_p (&momentary_obstack, object))
803 obstack = &momentary_obstack;
804 obstack_name = "momentary_obstack";
806 else if (_obstack_allocated_p (function_maybepermanent_obstack, object))
808 obstack = function_maybepermanent_obstack;
809 obstack_name = "function maybepermanent obstack";
811 else if (_obstack_allocated_p (&temp_decl_obstack, object))
813 obstack = &temp_decl_obstack;
814 obstack_name = "temp_decl_obstack";
817 /* Check to see if the object is in the free area of the obstack. */
820 if (object >= obstack->next_free
821 && object < obstack->chunk_limit)
822 fprintf (file, "%s in free portion of obstack %s",
823 prefix, obstack_name);
825 fprintf (file, "%s allocated from %s", prefix, obstack_name);
828 fprintf (file, "%s not allocated from any obstack", prefix);
832 debug_obstack (object)
835 print_obstack_name (object, stderr, "object");
836 fprintf (stderr, ".\n");
839 /* Return 1 if OBJ is in the permanent obstack.
840 This is slow, and should be used only for debugging.
841 Use TREE_PERMANENT for other purposes. */
844 object_permanent_p (obj)
847 return _obstack_allocated_p (&permanent_obstack, obj);
850 /* Start a level of momentary allocation.
851 In C, each compound statement has its own level
852 and that level is freed at the end of each statement.
853 All expression nodes are allocated in the momentary allocation level. */
858 struct momentary_level *tem
859 = (struct momentary_level *) obstack_alloc (&momentary_obstack,
860 sizeof (struct momentary_level));
861 tem->prev = momentary_stack;
862 tem->base = (char *) obstack_base (&momentary_obstack);
863 tem->obstack = expression_obstack;
864 momentary_stack = tem;
865 expression_obstack = &momentary_obstack;
868 /* Set things up so the next clear_momentary will only clear memory
869 past our present position in momentary_obstack. */
872 preserve_momentary ()
874 momentary_stack->base = (char *) obstack_base (&momentary_obstack);
877 /* Free all the storage in the current momentary-allocation level.
878 In C, this happens at the end of each statement. */
883 obstack_free (&momentary_obstack, momentary_stack->base);
886 /* Discard a level of momentary allocation.
887 In C, this happens at the end of each compound statement.
888 Restore the status of expression node allocation
889 that was in effect before this level was created. */
894 struct momentary_level *tem = momentary_stack;
895 momentary_stack = tem->prev;
896 expression_obstack = tem->obstack;
897 /* We can't free TEM from the momentary_obstack, because there might
898 be objects above it which have been saved. We can free back to the
899 stack of the level we are popping off though. */
900 obstack_free (&momentary_obstack, tem->base);
903 /* Pop back to the previous level of momentary allocation,
904 but don't free any momentary data just yet. */
907 pop_momentary_nofree ()
909 struct momentary_level *tem = momentary_stack;
910 momentary_stack = tem->prev;
911 expression_obstack = tem->obstack;
914 /* Call when starting to parse a declaration:
915 make expressions in the declaration last the length of the function.
916 Returns an argument that should be passed to resume_momentary later. */
921 register int tem = expression_obstack == &momentary_obstack;
922 expression_obstack = saveable_obstack;
926 /* Call when finished parsing a declaration:
927 restore the treatment of node-allocation that was
928 in effect before the suspension.
929 YES should be the value previously returned by suspend_momentary. */
932 resume_momentary (yes)
936 expression_obstack = &momentary_obstack;
939 /* Init the tables indexed by tree code.
940 Note that languages can add to these tables to define their own codes. */
945 tree_code_type = (char **) xmalloc (sizeof (standard_tree_code_type));
946 tree_code_length = (int *) xmalloc (sizeof (standard_tree_code_length));
947 tree_code_name = (char **) xmalloc (sizeof (standard_tree_code_name));
948 bcopy ((char *) standard_tree_code_type, (char *) tree_code_type,
949 sizeof (standard_tree_code_type));
950 bcopy ((char *) standard_tree_code_length, (char *) tree_code_length,
951 sizeof (standard_tree_code_length));
952 bcopy ((char *) standard_tree_code_name, (char *) tree_code_name,
953 sizeof (standard_tree_code_name));
956 /* Return a newly allocated node of code CODE.
957 Initialize the node's unique id and its TREE_PERMANENT flag.
958 For decl and type nodes, some other fields are initialized.
959 The rest of the node is initialized to zero.
961 Achoo! I got a code in the node. */
968 register int type = TREE_CODE_CLASS (code);
970 register struct obstack *obstack = current_obstack;
972 register tree_node_kind kind;
976 case 'd': /* A decl node */
977 #ifdef GATHER_STATISTICS
980 length = sizeof (struct tree_decl);
981 /* All decls in an inline function need to be saved. */
982 if (obstack != &permanent_obstack)
983 obstack = saveable_obstack;
985 /* PARM_DECLs go on the context of the parent. If this is a nested
986 function, then we must allocate the PARM_DECL on the parent's
987 obstack, so that they will live to the end of the parent's
988 closing brace. This is necessary in case we try to inline the
989 function into its parent.
991 PARM_DECLs of top-level functions do not have this problem. However,
992 we allocate them where we put the FUNCTION_DECL for languages such as
993 Ada that need to consult some flags in the PARM_DECLs of the function
996 See comment in restore_tree_status for why we can't put this
997 in function_obstack. */
998 if (code == PARM_DECL && obstack != &permanent_obstack)
1001 if (current_function_decl)
1002 context = decl_function_context (current_function_decl);
1006 = find_function_data (context)->function_maybepermanent_obstack;
1010 case 't': /* a type node */
1011 #ifdef GATHER_STATISTICS
1014 length = sizeof (struct tree_type);
1015 /* All data types are put where we can preserve them if nec. */
1016 if (obstack != &permanent_obstack)
1017 obstack = all_types_permanent ? &permanent_obstack : saveable_obstack;
1020 case 'b': /* a lexical block */
1021 #ifdef GATHER_STATISTICS
1024 length = sizeof (struct tree_block);
1025 /* All BLOCK nodes are put where we can preserve them if nec. */
1026 if (obstack != &permanent_obstack)
1027 obstack = saveable_obstack;
1030 case 's': /* an expression with side effects */
1031 #ifdef GATHER_STATISTICS
1035 case 'r': /* a reference */
1036 #ifdef GATHER_STATISTICS
1040 case 'e': /* an expression */
1041 case '<': /* a comparison expression */
1042 case '1': /* a unary arithmetic expression */
1043 case '2': /* a binary arithmetic expression */
1044 #ifdef GATHER_STATISTICS
1048 obstack = expression_obstack;
1049 /* All BIND_EXPR nodes are put where we can preserve them if nec. */
1050 if (code == BIND_EXPR && obstack != &permanent_obstack)
1051 obstack = saveable_obstack;
1052 length = sizeof (struct tree_exp)
1053 + (tree_code_length[(int) code] - 1) * sizeof (char *);
1056 case 'c': /* a constant */
1057 #ifdef GATHER_STATISTICS
1060 obstack = expression_obstack;
1062 /* We can't use tree_code_length for INTEGER_CST, since the number of
1063 words is machine-dependent due to varying length of HOST_WIDE_INT,
1064 which might be wider than a pointer (e.g., long long). Similarly
1065 for REAL_CST, since the number of words is machine-dependent due
1066 to varying size and alignment of `double'. */
1068 if (code == INTEGER_CST)
1069 length = sizeof (struct tree_int_cst);
1070 else if (code == REAL_CST)
1071 length = sizeof (struct tree_real_cst);
1073 length = sizeof (struct tree_common)
1074 + tree_code_length[(int) code] * sizeof (char *);
1077 case 'x': /* something random, like an identifier. */
1078 #ifdef GATHER_STATISTICS
1079 if (code == IDENTIFIER_NODE)
1081 else if (code == OP_IDENTIFIER)
1083 else if (code == TREE_VEC)
1088 length = sizeof (struct tree_common)
1089 + tree_code_length[(int) code] * sizeof (char *);
1090 /* Identifier nodes are always permanent since they are
1091 unique in a compiler run. */
1092 if (code == IDENTIFIER_NODE) obstack = &permanent_obstack;
1099 t = (tree) obstack_alloc (obstack, length);
1101 #ifdef GATHER_STATISTICS
1102 tree_node_counts[(int)kind]++;
1103 tree_node_sizes[(int)kind] += length;
1106 /* Clear a word at a time. */
1107 for (i = (length / sizeof (int)) - 1; i >= 0; i--)
1109 /* Clear any extra bytes. */
1110 for (i = length / sizeof (int) * sizeof (int); i < length; i++)
1111 ((char *) t)[i] = 0;
1113 TREE_SET_CODE (t, code);
1114 if (obstack == &permanent_obstack)
1115 TREE_PERMANENT (t) = 1;
1120 TREE_SIDE_EFFECTS (t) = 1;
1121 TREE_TYPE (t) = void_type_node;
1125 if (code != FUNCTION_DECL)
1127 DECL_IN_SYSTEM_HEADER (t)
1128 = in_system_header && (obstack == &permanent_obstack);
1129 DECL_SOURCE_LINE (t) = lineno;
1130 DECL_SOURCE_FILE (t) = (input_filename) ? input_filename : "<built-in>";
1131 DECL_UID (t) = next_decl_uid++;
1135 TYPE_UID (t) = next_type_uid++;
1137 TYPE_MAIN_VARIANT (t) = t;
1138 TYPE_OBSTACK (t) = obstack;
1139 TYPE_ATTRIBUTES (t) = NULL_TREE;
1140 #ifdef SET_DEFAULT_TYPE_ATTRIBUTES
1141 SET_DEFAULT_TYPE_ATTRIBUTES (t);
1146 TREE_CONSTANT (t) = 1;
1153 /* Return a new node with the same contents as NODE
1154 except that its TREE_CHAIN is zero and it has a fresh uid. */
1161 register enum tree_code code = TREE_CODE (node);
1162 register int length;
1165 switch (TREE_CODE_CLASS (code))
1167 case 'd': /* A decl node */
1168 length = sizeof (struct tree_decl);
1171 case 't': /* a type node */
1172 length = sizeof (struct tree_type);
1175 case 'b': /* a lexical block node */
1176 length = sizeof (struct tree_block);
1179 case 'r': /* a reference */
1180 case 'e': /* an expression */
1181 case 's': /* an expression with side effects */
1182 case '<': /* a comparison expression */
1183 case '1': /* a unary arithmetic expression */
1184 case '2': /* a binary arithmetic expression */
1185 length = sizeof (struct tree_exp)
1186 + (tree_code_length[(int) code] - 1) * sizeof (char *);
1189 case 'c': /* a constant */
1190 /* We can't use tree_code_length for INTEGER_CST, since the number of
1191 words is machine-dependent due to varying length of HOST_WIDE_INT,
1192 which might be wider than a pointer (e.g., long long). Similarly
1193 for REAL_CST, since the number of words is machine-dependent due
1194 to varying size and alignment of `double'. */
1195 if (code == INTEGER_CST)
1196 length = sizeof (struct tree_int_cst);
1197 else if (code == REAL_CST)
1198 length = sizeof (struct tree_real_cst);
1200 length = (sizeof (struct tree_common)
1201 + tree_code_length[(int) code] * sizeof (char *));
1204 case 'x': /* something random, like an identifier. */
1205 length = sizeof (struct tree_common)
1206 + tree_code_length[(int) code] * sizeof (char *);
1207 if (code == TREE_VEC)
1208 length += (TREE_VEC_LENGTH (node) - 1) * sizeof (char *);
1211 t = (tree) obstack_alloc (current_obstack, length);
1213 for (i = (length / sizeof (int)) - 1; i >= 0; i--)
1214 ((int *) t)[i] = ((int *) node)[i];
1215 /* Clear any extra bytes. */
1216 for (i = length / sizeof (int) * sizeof (int); i < length; i++)
1217 ((char *) t)[i] = ((char *) node)[i];
1220 TREE_ASM_WRITTEN (t) = 0;
1222 if (TREE_CODE_CLASS (code) == 'd')
1223 DECL_UID (t) = next_decl_uid++;
1224 else if (TREE_CODE_CLASS (code) == 't')
1226 TYPE_UID (t) = next_type_uid++;
1227 TYPE_OBSTACK (t) = current_obstack;
1229 /* The following is so that the debug code for
1230 the copy is different from the original type.
1231 The two statements usually duplicate each other
1232 (because they clear fields of the same union),
1233 but the optimizer should catch that. */
1234 TYPE_SYMTAB_POINTER (t) = 0;
1235 TYPE_SYMTAB_ADDRESS (t) = 0;
1238 TREE_PERMANENT (t) = (current_obstack == &permanent_obstack);
1243 /* Return a copy of a chain of nodes, chained through the TREE_CHAIN field.
1244 For example, this can copy a list made of TREE_LIST nodes. */
1251 register tree prev, next;
1256 head = prev = copy_node (list);
1257 next = TREE_CHAIN (list);
1260 TREE_CHAIN (prev) = copy_node (next);
1261 prev = TREE_CHAIN (prev);
1262 next = TREE_CHAIN (next);
1269 /* Return an IDENTIFIER_NODE whose name is TEXT (a null-terminated string).
1270 If an identifier with that name has previously been referred to,
1271 the same node is returned this time. */
1274 get_identifier (text)
1275 register char *text;
1280 register int len, hash_len;
1282 /* Compute length of text in len. */
1283 for (len = 0; text[len]; len++);
1285 /* Decide how much of that length to hash on */
1287 if (warn_id_clash && len > id_clash_len)
1288 hash_len = id_clash_len;
1290 /* Compute hash code */
1291 hi = hash_len * 613 + (unsigned) text[0];
1292 for (i = 1; i < hash_len; i += 2)
1293 hi = ((hi * 613) + (unsigned) (text[i]));
1295 hi &= (1 << HASHBITS) - 1;
1296 hi %= MAX_HASH_TABLE;
1298 /* Search table for identifier */
1299 for (idp = hash_table[hi]; idp; idp = TREE_CHAIN (idp))
1300 if (IDENTIFIER_LENGTH (idp) == len
1301 && IDENTIFIER_POINTER (idp)[0] == text[0]
1302 && !bcmp (IDENTIFIER_POINTER (idp), text, len))
1303 return idp; /* <-- return if found */
1305 /* Not found; optionally warn about a similar identifier */
1306 if (warn_id_clash && do_identifier_warnings && len >= id_clash_len)
1307 for (idp = hash_table[hi]; idp; idp = TREE_CHAIN (idp))
1308 if (!strncmp (IDENTIFIER_POINTER (idp), text, id_clash_len))
1310 warning ("`%s' and `%s' identical in first %d characters",
1311 IDENTIFIER_POINTER (idp), text, id_clash_len);
1315 if (tree_code_length[(int) IDENTIFIER_NODE] < 0)
1316 abort (); /* set_identifier_size hasn't been called. */
1318 /* Not found, create one, add to chain */
1319 idp = make_node (IDENTIFIER_NODE);
1320 IDENTIFIER_LENGTH (idp) = len;
1321 #ifdef GATHER_STATISTICS
1322 id_string_size += len;
1325 IDENTIFIER_POINTER (idp) = obstack_copy0 (&permanent_obstack, text, len);
1327 TREE_CHAIN (idp) = hash_table[hi];
1328 hash_table[hi] = idp;
1329 return idp; /* <-- return if created */
1332 /* If an identifier with the name TEXT (a null-terminated string) has
1333 previously been referred to, return that node; otherwise return
1337 maybe_get_identifier (text)
1338 register char *text;
1343 register int len, hash_len;
1345 /* Compute length of text in len. */
1346 for (len = 0; text[len]; len++);
1348 /* Decide how much of that length to hash on */
1350 if (warn_id_clash && len > id_clash_len)
1351 hash_len = id_clash_len;
1353 /* Compute hash code */
1354 hi = hash_len * 613 + (unsigned) text[0];
1355 for (i = 1; i < hash_len; i += 2)
1356 hi = ((hi * 613) + (unsigned) (text[i]));
1358 hi &= (1 << HASHBITS) - 1;
1359 hi %= MAX_HASH_TABLE;
1361 /* Search table for identifier */
1362 for (idp = hash_table[hi]; idp; idp = TREE_CHAIN (idp))
1363 if (IDENTIFIER_LENGTH (idp) == len
1364 && IDENTIFIER_POINTER (idp)[0] == text[0]
1365 && !bcmp (IDENTIFIER_POINTER (idp), text, len))
1366 return idp; /* <-- return if found */
1371 /* Enable warnings on similar identifiers (if requested).
1372 Done after the built-in identifiers are created. */
1375 start_identifier_warnings ()
1377 do_identifier_warnings = 1;
1380 /* Record the size of an identifier node for the language in use.
1381 SIZE is the total size in bytes.
1382 This is called by the language-specific files. This must be
1383 called before allocating any identifiers. */
1386 set_identifier_size (size)
1389 tree_code_length[(int) IDENTIFIER_NODE]
1390 = (size - sizeof (struct tree_common)) / sizeof (tree);
1393 /* Return a newly constructed INTEGER_CST node whose constant value
1394 is specified by the two ints LOW and HI.
1395 The TREE_TYPE is set to `int'.
1397 This function should be used via the `build_int_2' macro. */
1400 build_int_2_wide (low, hi)
1401 HOST_WIDE_INT low, hi;
1403 register tree t = make_node (INTEGER_CST);
1404 TREE_INT_CST_LOW (t) = low;
1405 TREE_INT_CST_HIGH (t) = hi;
1406 TREE_TYPE (t) = integer_type_node;
1410 /* Return a new REAL_CST node whose type is TYPE and value is D. */
1413 build_real (type, d)
1420 /* Check for valid float value for this type on this target machine;
1421 if not, can print error message and store a valid value in D. */
1422 #ifdef CHECK_FLOAT_VALUE
1423 CHECK_FLOAT_VALUE (TYPE_MODE (type), d, overflow);
1426 v = make_node (REAL_CST);
1427 TREE_TYPE (v) = type;
1428 TREE_REAL_CST (v) = d;
1429 TREE_OVERFLOW (v) = TREE_CONSTANT_OVERFLOW (v) = overflow;
1433 /* Return a new REAL_CST node whose type is TYPE
1434 and whose value is the integer value of the INTEGER_CST node I. */
1436 #if !defined (REAL_IS_NOT_DOUBLE) || defined (REAL_ARITHMETIC)
1439 real_value_from_int_cst (type, i)
1444 /* Some 386 compilers mishandle unsigned int to float conversions,
1445 so introduce a temporary variable E to avoid those bugs. */
1447 #ifdef REAL_ARITHMETIC
1448 if (! TREE_UNSIGNED (TREE_TYPE (i)))
1449 REAL_VALUE_FROM_INT (d, TREE_INT_CST_LOW (i), TREE_INT_CST_HIGH (i),
1452 REAL_VALUE_FROM_UNSIGNED_INT (d, TREE_INT_CST_LOW (i),
1453 TREE_INT_CST_HIGH (i), TYPE_MODE (type));
1454 #else /* not REAL_ARITHMETIC */
1455 if (TREE_INT_CST_HIGH (i) < 0 && ! TREE_UNSIGNED (TREE_TYPE (i)))
1457 d = (double) (~ TREE_INT_CST_HIGH (i));
1458 e = ((double) ((HOST_WIDE_INT) 1 << (HOST_BITS_PER_WIDE_INT / 2))
1459 * (double) ((HOST_WIDE_INT) 1 << (HOST_BITS_PER_WIDE_INT / 2)));
1461 e = (double) (unsigned HOST_WIDE_INT) (~ TREE_INT_CST_LOW (i));
1467 d = (double) (unsigned HOST_WIDE_INT) TREE_INT_CST_HIGH (i);
1468 e = ((double) ((HOST_WIDE_INT) 1 << (HOST_BITS_PER_WIDE_INT / 2))
1469 * (double) ((HOST_WIDE_INT) 1 << (HOST_BITS_PER_WIDE_INT / 2)));
1471 e = (double) (unsigned HOST_WIDE_INT) TREE_INT_CST_LOW (i);
1474 #endif /* not REAL_ARITHMETIC */
1478 /* This function can't be implemented if we can't do arithmetic
1479 on the float representation. */
1482 build_real_from_int_cst (type, i)
1487 int overflow = TREE_OVERFLOW (i);
1489 jmp_buf float_error;
1491 v = make_node (REAL_CST);
1492 TREE_TYPE (v) = type;
1494 if (setjmp (float_error))
1501 set_float_handler (float_error);
1503 #ifdef REAL_ARITHMETIC
1504 d = real_value_from_int_cst (type, i);
1506 d = REAL_VALUE_TRUNCATE (TYPE_MODE (type),
1507 real_value_from_int_cst (type, i));
1510 /* Check for valid float value for this type on this target machine. */
1513 set_float_handler (NULL_PTR);
1515 #ifdef CHECK_FLOAT_VALUE
1516 CHECK_FLOAT_VALUE (TYPE_MODE (type), d, overflow);
1519 TREE_REAL_CST (v) = d;
1520 TREE_OVERFLOW (v) = TREE_CONSTANT_OVERFLOW (v) = overflow;
1524 #endif /* not REAL_IS_NOT_DOUBLE, or REAL_ARITHMETIC */
1526 /* Return a newly constructed STRING_CST node whose value is
1527 the LEN characters at STR.
1528 The TREE_TYPE is not initialized. */
1531 build_string (len, str)
1535 /* Put the string in saveable_obstack since it will be placed in the RTL
1536 for an "asm" statement and will also be kept around a while if
1537 deferring constant output in varasm.c. */
1539 register tree s = make_node (STRING_CST);
1540 TREE_STRING_LENGTH (s) = len;
1541 TREE_STRING_POINTER (s) = obstack_copy0 (saveable_obstack, str, len);
1545 /* Return a newly constructed COMPLEX_CST node whose value is
1546 specified by the real and imaginary parts REAL and IMAG.
1547 Both REAL and IMAG should be constant nodes. TYPE, if specified,
1548 will be the type of the COMPLEX_CST; otherwise a new type will be made. */
1551 build_complex (type, real, imag)
1555 register tree t = make_node (COMPLEX_CST);
1557 TREE_REALPART (t) = real;
1558 TREE_IMAGPART (t) = imag;
1559 TREE_TYPE (t) = type ? type : build_complex_type (TREE_TYPE (real));
1560 TREE_OVERFLOW (t) = TREE_OVERFLOW (real) | TREE_OVERFLOW (imag);
1561 TREE_CONSTANT_OVERFLOW (t)
1562 = TREE_CONSTANT_OVERFLOW (real) | TREE_CONSTANT_OVERFLOW (imag);
1566 /* Build a newly constructed TREE_VEC node of length LEN. */
1573 register int length = (len-1) * sizeof (tree) + sizeof (struct tree_vec);
1574 register struct obstack *obstack = current_obstack;
1577 #ifdef GATHER_STATISTICS
1578 tree_node_counts[(int)vec_kind]++;
1579 tree_node_sizes[(int)vec_kind] += length;
1582 t = (tree) obstack_alloc (obstack, length);
1584 for (i = (length / sizeof (int)) - 1; i >= 0; i--)
1587 TREE_SET_CODE (t, TREE_VEC);
1588 TREE_VEC_LENGTH (t) = len;
1589 if (obstack == &permanent_obstack)
1590 TREE_PERMANENT (t) = 1;
1595 /* Return 1 if EXPR is the integer constant zero or a complex constant
1599 integer_zerop (expr)
1604 return ((TREE_CODE (expr) == INTEGER_CST
1605 && ! TREE_CONSTANT_OVERFLOW (expr)
1606 && TREE_INT_CST_LOW (expr) == 0
1607 && TREE_INT_CST_HIGH (expr) == 0)
1608 || (TREE_CODE (expr) == COMPLEX_CST
1609 && integer_zerop (TREE_REALPART (expr))
1610 && integer_zerop (TREE_IMAGPART (expr))));
1613 /* Return 1 if EXPR is the integer constant one or the corresponding
1614 complex constant. */
1622 return ((TREE_CODE (expr) == INTEGER_CST
1623 && ! TREE_CONSTANT_OVERFLOW (expr)
1624 && TREE_INT_CST_LOW (expr) == 1
1625 && TREE_INT_CST_HIGH (expr) == 0)
1626 || (TREE_CODE (expr) == COMPLEX_CST
1627 && integer_onep (TREE_REALPART (expr))
1628 && integer_zerop (TREE_IMAGPART (expr))));
1631 /* Return 1 if EXPR is an integer containing all 1's in as much precision as
1632 it contains. Likewise for the corresponding complex constant. */
1635 integer_all_onesp (expr)
1643 if (TREE_CODE (expr) == COMPLEX_CST
1644 && integer_all_onesp (TREE_REALPART (expr))
1645 && integer_zerop (TREE_IMAGPART (expr)))
1648 else if (TREE_CODE (expr) != INTEGER_CST
1649 || TREE_CONSTANT_OVERFLOW (expr))
1652 uns = TREE_UNSIGNED (TREE_TYPE (expr));
1654 return TREE_INT_CST_LOW (expr) == -1 && TREE_INT_CST_HIGH (expr) == -1;
1656 /* Note that using TYPE_PRECISION here is wrong. We care about the
1657 actual bits, not the (arbitrary) range of the type. */
1658 prec = GET_MODE_BITSIZE (TYPE_MODE (TREE_TYPE (expr)));
1659 if (prec >= HOST_BITS_PER_WIDE_INT)
1661 int high_value, shift_amount;
1663 shift_amount = prec - HOST_BITS_PER_WIDE_INT;
1665 if (shift_amount > HOST_BITS_PER_WIDE_INT)
1666 /* Can not handle precisions greater than twice the host int size. */
1668 else if (shift_amount == HOST_BITS_PER_WIDE_INT)
1669 /* Shifting by the host word size is undefined according to the ANSI
1670 standard, so we must handle this as a special case. */
1673 high_value = ((HOST_WIDE_INT) 1 << shift_amount) - 1;
1675 return TREE_INT_CST_LOW (expr) == -1
1676 && TREE_INT_CST_HIGH (expr) == high_value;
1679 return TREE_INT_CST_LOW (expr) == ((HOST_WIDE_INT) 1 << prec) - 1;
1682 /* Return 1 if EXPR is an integer constant that is a power of 2 (i.e., has only
1686 integer_pow2p (expr)
1690 HOST_WIDE_INT high, low;
1694 if (TREE_CODE (expr) == COMPLEX_CST
1695 && integer_pow2p (TREE_REALPART (expr))
1696 && integer_zerop (TREE_IMAGPART (expr)))
1699 if (TREE_CODE (expr) != INTEGER_CST || TREE_CONSTANT_OVERFLOW (expr))
1702 prec = (TREE_CODE (TREE_TYPE (expr)) == POINTER_TYPE
1703 ? POINTER_SIZE : TYPE_PRECISION (TREE_TYPE (expr)));
1704 high = TREE_INT_CST_HIGH (expr);
1705 low = TREE_INT_CST_LOW (expr);
1707 /* First clear all bits that are beyond the type's precision in case
1708 we've been sign extended. */
1710 if (prec == 2 * HOST_BITS_PER_WIDE_INT)
1712 else if (prec > HOST_BITS_PER_WIDE_INT)
1713 high &= ~((HOST_WIDE_INT) (-1) << (prec - HOST_BITS_PER_WIDE_INT));
1717 if (prec < HOST_BITS_PER_WIDE_INT)
1718 low &= ~((HOST_WIDE_INT) (-1) << prec);
1721 if (high == 0 && low == 0)
1724 return ((high == 0 && (low & (low - 1)) == 0)
1725 || (low == 0 && (high & (high - 1)) == 0));
1728 /* Return the power of two represented by a tree node known to be a
1736 HOST_WIDE_INT high, low;
1740 if (TREE_CODE (expr) == COMPLEX_CST)
1741 return tree_log2 (TREE_REALPART (expr));
1743 prec = (TREE_CODE (TREE_TYPE (expr)) == POINTER_TYPE
1744 ? POINTER_SIZE : TYPE_PRECISION (TREE_TYPE (expr)));
1746 high = TREE_INT_CST_HIGH (expr);
1747 low = TREE_INT_CST_LOW (expr);
1749 /* First clear all bits that are beyond the type's precision in case
1750 we've been sign extended. */
1752 if (prec == 2 * HOST_BITS_PER_WIDE_INT)
1754 else if (prec > HOST_BITS_PER_WIDE_INT)
1755 high &= ~((HOST_WIDE_INT) (-1) << (prec - HOST_BITS_PER_WIDE_INT));
1759 if (prec < HOST_BITS_PER_WIDE_INT)
1760 low &= ~((HOST_WIDE_INT) (-1) << prec);
1763 return (high != 0 ? HOST_BITS_PER_WIDE_INT + exact_log2 (high)
1764 : exact_log2 (low));
1767 /* Return 1 if EXPR is the real constant zero. */
1775 return ((TREE_CODE (expr) == REAL_CST
1776 && ! TREE_CONSTANT_OVERFLOW (expr)
1777 && REAL_VALUES_EQUAL (TREE_REAL_CST (expr), dconst0))
1778 || (TREE_CODE (expr) == COMPLEX_CST
1779 && real_zerop (TREE_REALPART (expr))
1780 && real_zerop (TREE_IMAGPART (expr))));
1783 /* Return 1 if EXPR is the real constant one in real or complex form. */
1791 return ((TREE_CODE (expr) == REAL_CST
1792 && ! TREE_CONSTANT_OVERFLOW (expr)
1793 && REAL_VALUES_EQUAL (TREE_REAL_CST (expr), dconst1))
1794 || (TREE_CODE (expr) == COMPLEX_CST
1795 && real_onep (TREE_REALPART (expr))
1796 && real_zerop (TREE_IMAGPART (expr))));
1799 /* Return 1 if EXPR is the real constant two. */
1807 return ((TREE_CODE (expr) == REAL_CST
1808 && ! TREE_CONSTANT_OVERFLOW (expr)
1809 && REAL_VALUES_EQUAL (TREE_REAL_CST (expr), dconst2))
1810 || (TREE_CODE (expr) == COMPLEX_CST
1811 && real_twop (TREE_REALPART (expr))
1812 && real_zerop (TREE_IMAGPART (expr))));
1815 /* Nonzero if EXP is a constant or a cast of a constant. */
1818 really_constant_p (exp)
1821 /* This is not quite the same as STRIP_NOPS. It does more. */
1822 while (TREE_CODE (exp) == NOP_EXPR
1823 || TREE_CODE (exp) == CONVERT_EXPR
1824 || TREE_CODE (exp) == NON_LVALUE_EXPR)
1825 exp = TREE_OPERAND (exp, 0);
1826 return TREE_CONSTANT (exp);
1829 /* Return first list element whose TREE_VALUE is ELEM.
1830 Return 0 if ELEM is not in LIST. */
1833 value_member (elem, list)
1838 if (elem == TREE_VALUE (list))
1840 list = TREE_CHAIN (list);
1845 /* Return first list element whose TREE_PURPOSE is ELEM.
1846 Return 0 if ELEM is not in LIST. */
1849 purpose_member (elem, list)
1854 if (elem == TREE_PURPOSE (list))
1856 list = TREE_CHAIN (list);
1861 /* Return first list element whose BINFO_TYPE is ELEM.
1862 Return 0 if ELEM is not in LIST. */
1865 binfo_member (elem, list)
1870 if (elem == BINFO_TYPE (list))
1872 list = TREE_CHAIN (list);
1877 /* Return nonzero if ELEM is part of the chain CHAIN. */
1880 chain_member (elem, chain)
1887 chain = TREE_CHAIN (chain);
1893 /* Return nonzero if ELEM is equal to TREE_VALUE (CHAIN) for any piece of
1895 /* ??? This function was added for machine specific attributes but is no
1896 longer used. It could be deleted if we could confirm all front ends
1900 chain_member_value (elem, chain)
1905 if (elem == TREE_VALUE (chain))
1907 chain = TREE_CHAIN (chain);
1913 /* Return nonzero if ELEM is equal to TREE_PURPOSE (CHAIN)
1914 for any piece of chain CHAIN. */
1915 /* ??? This function was added for machine specific attributes but is no
1916 longer used. It could be deleted if we could confirm all front ends
1920 chain_member_purpose (elem, chain)
1925 if (elem == TREE_PURPOSE (chain))
1927 chain = TREE_CHAIN (chain);
1933 /* Return the length of a chain of nodes chained through TREE_CHAIN.
1934 We expect a null pointer to mark the end of the chain.
1935 This is the Lisp primitive `length'. */
1942 register int len = 0;
1944 for (tail = t; tail; tail = TREE_CHAIN (tail))
1950 /* Concatenate two chains of nodes (chained through TREE_CHAIN)
1951 by modifying the last node in chain 1 to point to chain 2.
1952 This is the Lisp primitive `nconc'. */
1964 for (t1 = op1; TREE_CHAIN (t1); t1 = TREE_CHAIN (t1))
1966 TREE_CHAIN (t1) = op2;
1967 for (t2 = op2; t2; t2 = TREE_CHAIN (t2))
1969 abort (); /* Circularity created. */
1975 /* Return the last node in a chain of nodes (chained through TREE_CHAIN). */
1979 register tree chain;
1983 while (next = TREE_CHAIN (chain))
1988 /* Reverse the order of elements in the chain T,
1989 and return the new head of the chain (old last element). */
1995 register tree prev = 0, decl, next;
1996 for (decl = t; decl; decl = next)
1998 next = TREE_CHAIN (decl);
1999 TREE_CHAIN (decl) = prev;
2005 /* Given a chain CHAIN of tree nodes,
2006 construct and return a list of those nodes. */
2012 tree result = NULL_TREE;
2013 tree in_tail = chain;
2014 tree out_tail = NULL_TREE;
2018 tree next = tree_cons (NULL_TREE, in_tail, NULL_TREE);
2020 TREE_CHAIN (out_tail) = next;
2024 in_tail = TREE_CHAIN (in_tail);
2030 /* Return a newly created TREE_LIST node whose
2031 purpose and value fields are PARM and VALUE. */
2034 build_tree_list (parm, value)
2037 register tree t = make_node (TREE_LIST);
2038 TREE_PURPOSE (t) = parm;
2039 TREE_VALUE (t) = value;
2043 /* Similar, but build on the temp_decl_obstack. */
2046 build_decl_list (parm, value)
2050 register struct obstack *ambient_obstack = current_obstack;
2051 current_obstack = &temp_decl_obstack;
2052 node = build_tree_list (parm, value);
2053 current_obstack = ambient_obstack;
2057 /* Similar, but build on the expression_obstack. */
2060 build_expr_list (parm, value)
2064 register struct obstack *ambient_obstack = current_obstack;
2065 current_obstack = expression_obstack;
2066 node = build_tree_list (parm, value);
2067 current_obstack = ambient_obstack;
2071 /* Return a newly created TREE_LIST node whose
2072 purpose and value fields are PARM and VALUE
2073 and whose TREE_CHAIN is CHAIN. */
2076 tree_cons (purpose, value, chain)
2077 tree purpose, value, chain;
2080 register tree node = make_node (TREE_LIST);
2083 register tree node = (tree) obstack_alloc (current_obstack, sizeof (struct tree_list));
2084 #ifdef GATHER_STATISTICS
2085 tree_node_counts[(int)x_kind]++;
2086 tree_node_sizes[(int)x_kind] += sizeof (struct tree_list);
2089 for (i = (sizeof (struct tree_common) / sizeof (int)) - 1; i >= 0; i--)
2090 ((int *) node)[i] = 0;
2092 TREE_SET_CODE (node, TREE_LIST);
2093 if (current_obstack == &permanent_obstack)
2094 TREE_PERMANENT (node) = 1;
2097 TREE_CHAIN (node) = chain;
2098 TREE_PURPOSE (node) = purpose;
2099 TREE_VALUE (node) = value;
2103 /* Similar, but build on the temp_decl_obstack. */
2106 decl_tree_cons (purpose, value, chain)
2107 tree purpose, value, chain;
2110 register struct obstack *ambient_obstack = current_obstack;
2111 current_obstack = &temp_decl_obstack;
2112 node = tree_cons (purpose, value, chain);
2113 current_obstack = ambient_obstack;
2117 /* Similar, but build on the expression_obstack. */
2120 expr_tree_cons (purpose, value, chain)
2121 tree purpose, value, chain;
2124 register struct obstack *ambient_obstack = current_obstack;
2125 current_obstack = expression_obstack;
2126 node = tree_cons (purpose, value, chain);
2127 current_obstack = ambient_obstack;
2131 /* Same as `tree_cons' but make a permanent object. */
2134 perm_tree_cons (purpose, value, chain)
2135 tree purpose, value, chain;
2138 register struct obstack *ambient_obstack = current_obstack;
2139 current_obstack = &permanent_obstack;
2141 node = tree_cons (purpose, value, chain);
2142 current_obstack = ambient_obstack;
2146 /* Same as `tree_cons', but make this node temporary, regardless. */
2149 temp_tree_cons (purpose, value, chain)
2150 tree purpose, value, chain;
2153 register struct obstack *ambient_obstack = current_obstack;
2154 current_obstack = &temporary_obstack;
2156 node = tree_cons (purpose, value, chain);
2157 current_obstack = ambient_obstack;
2161 /* Same as `tree_cons', but save this node if the function's RTL is saved. */
2164 saveable_tree_cons (purpose, value, chain)
2165 tree purpose, value, chain;
2168 register struct obstack *ambient_obstack = current_obstack;
2169 current_obstack = saveable_obstack;
2171 node = tree_cons (purpose, value, chain);
2172 current_obstack = ambient_obstack;
2176 /* Return the size nominally occupied by an object of type TYPE
2177 when it resides in memory. The value is measured in units of bytes,
2178 and its data type is that normally used for type sizes
2179 (which is the first type created by make_signed_type or
2180 make_unsigned_type). */
2183 size_in_bytes (type)
2188 if (type == error_mark_node)
2189 return integer_zero_node;
2190 type = TYPE_MAIN_VARIANT (type);
2191 if (TYPE_SIZE (type) == 0)
2193 incomplete_type_error (NULL_TREE, type);
2194 return integer_zero_node;
2196 t = size_binop (CEIL_DIV_EXPR, TYPE_SIZE (type),
2197 size_int (BITS_PER_UNIT));
2198 if (TREE_CODE (t) == INTEGER_CST)
2199 force_fit_type (t, 0);
2203 /* Return the size of TYPE (in bytes) as an integer,
2204 or return -1 if the size can vary. */
2207 int_size_in_bytes (type)
2211 if (type == error_mark_node)
2213 type = TYPE_MAIN_VARIANT (type);
2214 if (TYPE_SIZE (type) == 0)
2216 if (TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
2218 if (TREE_INT_CST_HIGH (TYPE_SIZE (type)) != 0)
2220 tree t = size_binop (CEIL_DIV_EXPR, TYPE_SIZE (type),
2221 size_int (BITS_PER_UNIT));
2222 return TREE_INT_CST_LOW (t);
2224 size = TREE_INT_CST_LOW (TYPE_SIZE (type));
2225 return (size + BITS_PER_UNIT - 1) / BITS_PER_UNIT;
2228 /* Return, as a tree node, the number of elements for TYPE (which is an
2229 ARRAY_TYPE) minus one. This counts only elements of the top array.
2231 Don't let any SAVE_EXPRs escape; if we are called as part of a cleanup
2232 action, they would get unsaved. */
2235 array_type_nelts (type)
2238 tree index_type, min, max;
2240 /* If they did it with unspecified bounds, then we should have already
2241 given an error about it before we got here. */
2242 if (! TYPE_DOMAIN (type))
2243 return error_mark_node;
2245 index_type = TYPE_DOMAIN (type);
2246 min = TYPE_MIN_VALUE (index_type);
2247 max = TYPE_MAX_VALUE (index_type);
2249 if (! TREE_CONSTANT (min))
2252 if (TREE_CODE (min) == SAVE_EXPR)
2253 min = build (RTL_EXPR, TREE_TYPE (TYPE_MIN_VALUE (index_type)), 0,
2254 SAVE_EXPR_RTL (min));
2256 min = TYPE_MIN_VALUE (index_type);
2259 if (! TREE_CONSTANT (max))
2262 if (TREE_CODE (max) == SAVE_EXPR)
2263 max = build (RTL_EXPR, TREE_TYPE (TYPE_MAX_VALUE (index_type)), 0,
2264 SAVE_EXPR_RTL (max));
2266 max = TYPE_MAX_VALUE (index_type);
2269 return (integer_zerop (min)
2271 : fold (build (MINUS_EXPR, TREE_TYPE (max), max, min)));
2274 /* Return nonzero if arg is static -- a reference to an object in
2275 static storage. This is not the same as the C meaning of `static'. */
2281 switch (TREE_CODE (arg))
2284 /* Nested functions aren't static, since taking their address
2285 involves a trampoline. */
2286 return decl_function_context (arg) == 0 || DECL_NO_STATIC_CHAIN (arg);
2288 return TREE_STATIC (arg) || DECL_EXTERNAL (arg);
2291 return TREE_STATIC (arg);
2296 /* If we are referencing a bitfield, we can't evaluate an
2297 ADDR_EXPR at compile time and so it isn't a constant. */
2299 return (! DECL_BIT_FIELD (TREE_OPERAND (arg, 1))
2300 && staticp (TREE_OPERAND (arg, 0)));
2306 /* This case is technically correct, but results in setting
2307 TREE_CONSTANT on ADDR_EXPRs that cannot be evaluated at
2310 return TREE_CONSTANT (TREE_OPERAND (arg, 0));
2314 if (TREE_CODE (TYPE_SIZE (TREE_TYPE (arg))) == INTEGER_CST
2315 && TREE_CODE (TREE_OPERAND (arg, 1)) == INTEGER_CST)
2316 return staticp (TREE_OPERAND (arg, 0));
2323 /* Wrap a SAVE_EXPR around EXPR, if appropriate.
2324 Do this to any expression which may be used in more than one place,
2325 but must be evaluated only once.
2327 Normally, expand_expr would reevaluate the expression each time.
2328 Calling save_expr produces something that is evaluated and recorded
2329 the first time expand_expr is called on it. Subsequent calls to
2330 expand_expr just reuse the recorded value.
2332 The call to expand_expr that generates code that actually computes
2333 the value is the first call *at compile time*. Subsequent calls
2334 *at compile time* generate code to use the saved value.
2335 This produces correct result provided that *at run time* control
2336 always flows through the insns made by the first expand_expr
2337 before reaching the other places where the save_expr was evaluated.
2338 You, the caller of save_expr, must make sure this is so.
2340 Constants, and certain read-only nodes, are returned with no
2341 SAVE_EXPR because that is safe. Expressions containing placeholders
2342 are not touched; see tree.def for an explanation of what these
2349 register tree t = fold (expr);
2351 /* We don't care about whether this can be used as an lvalue in this
2353 while (TREE_CODE (t) == NON_LVALUE_EXPR)
2354 t = TREE_OPERAND (t, 0);
2356 /* If the tree evaluates to a constant, then we don't want to hide that
2357 fact (i.e. this allows further folding, and direct checks for constants).
2358 However, a read-only object that has side effects cannot be bypassed.
2359 Since it is no problem to reevaluate literals, we just return the
2362 if (TREE_CONSTANT (t) || (TREE_READONLY (t) && ! TREE_SIDE_EFFECTS (t))
2363 || TREE_CODE (t) == SAVE_EXPR || TREE_CODE (t) == ERROR_MARK)
2366 /* If T contains a PLACEHOLDER_EXPR, we must evaluate it each time, since
2367 it means that the size or offset of some field of an object depends on
2368 the value within another field.
2370 Note that it must not be the case that T contains both a PLACEHOLDER_EXPR
2371 and some variable since it would then need to be both evaluated once and
2372 evaluated more than once. Front-ends must assure this case cannot
2373 happen by surrounding any such subexpressions in their own SAVE_EXPR
2374 and forcing evaluation at the proper time. */
2375 if (contains_placeholder_p (t))
2378 t = build (SAVE_EXPR, TREE_TYPE (expr), t, current_function_decl, NULL_TREE);
2380 /* This expression might be placed ahead of a jump to ensure that the
2381 value was computed on both sides of the jump. So make sure it isn't
2382 eliminated as dead. */
2383 TREE_SIDE_EFFECTS (t) = 1;
2387 /* Arrange for an expression to be expanded multiple independent
2388 times. This is useful for cleanup actions, as the backend can
2389 expand them multiple times in different places. */
2397 /* If this is already protected, no sense in protecting it again. */
2398 if (TREE_CODE (expr) == UNSAVE_EXPR)
2401 t = build1 (UNSAVE_EXPR, TREE_TYPE (expr), expr);
2402 TREE_SIDE_EFFECTS (t) = TREE_SIDE_EFFECTS (expr);
2406 /* Modify a tree in place so that all the evaluate only once things
2407 are cleared out. Return the EXPR given. */
2410 unsave_expr_now (expr)
2413 enum tree_code code;
2417 if (expr == NULL_TREE)
2420 code = TREE_CODE (expr);
2421 first_rtl = tree_code_length [(int) code];
2425 SAVE_EXPR_RTL (expr) = 0;
2430 TREE_OPERAND (expr, 1) = TREE_OPERAND (expr, 3);
2431 TREE_OPERAND (expr, 3) = NULL_TREE;
2435 /* I don't yet know how to emit a sequence multiple times. */
2436 if (RTL_EXPR_SEQUENCE (expr) != 0)
2442 CALL_EXPR_RTL (expr) = 0;
2443 if (TREE_OPERAND (expr, 1)
2444 && TREE_CODE (TREE_OPERAND (expr, 1)) == TREE_LIST)
2446 tree exp = TREE_OPERAND (expr, 1);
2449 unsave_expr_now (TREE_VALUE (exp));
2450 exp = TREE_CHAIN (exp);
2456 case WITH_CLEANUP_EXPR:
2457 /* Should be defined to be 2. */
2461 case METHOD_CALL_EXPR:
2469 switch (TREE_CODE_CLASS (code))
2471 case 'c': /* a constant */
2472 case 't': /* a type node */
2473 case 'x': /* something random, like an identifier or an ERROR_MARK. */
2474 case 'd': /* A decl node */
2475 case 'b': /* A block node */
2478 case 'e': /* an expression */
2479 case 'r': /* a reference */
2480 case 's': /* an expression with side effects */
2481 case '<': /* a comparison expression */
2482 case '2': /* a binary arithmetic expression */
2483 case '1': /* a unary arithmetic expression */
2484 for (i = first_rtl - 1; i >= 0; i--)
2485 unsave_expr_now (TREE_OPERAND (expr, i));
2493 /* Return 1 if EXP contains a PLACEHOLDER_EXPR; i.e., if it represents a size
2494 or offset that depends on a field within a record. */
2497 contains_placeholder_p (exp)
2500 register enum tree_code code = TREE_CODE (exp);
2503 /* If we have a WITH_RECORD_EXPR, it "cancels" any PLACEHOLDER_EXPR
2504 in it since it is supplying a value for it. */
2505 if (code == WITH_RECORD_EXPR)
2507 else if (code == PLACEHOLDER_EXPR)
2510 switch (TREE_CODE_CLASS (code))
2513 /* Don't look at any PLACEHOLDER_EXPRs that might be in index or bit
2514 position computations since they will be converted into a
2515 WITH_RECORD_EXPR involving the reference, which will assume
2516 here will be valid. */
2517 return contains_placeholder_p (TREE_OPERAND (exp, 0));
2520 if (code == TREE_LIST)
2521 return (contains_placeholder_p (TREE_VALUE (exp))
2522 || (TREE_CHAIN (exp) != 0
2523 && contains_placeholder_p (TREE_CHAIN (exp))));
2532 /* Ignoring the first operand isn't quite right, but works best. */
2533 return contains_placeholder_p (TREE_OPERAND (exp, 1));
2540 return (contains_placeholder_p (TREE_OPERAND (exp, 0))
2541 || contains_placeholder_p (TREE_OPERAND (exp, 1))
2542 || contains_placeholder_p (TREE_OPERAND (exp, 2)));
2545 /* If we already know this doesn't have a placeholder, don't
2547 if (SAVE_EXPR_NOPLACEHOLDER (exp) || SAVE_EXPR_RTL (exp) != 0)
2550 SAVE_EXPR_NOPLACEHOLDER (exp) = 1;
2551 result = contains_placeholder_p (TREE_OPERAND (exp, 0));
2553 SAVE_EXPR_NOPLACEHOLDER (exp) = 0;
2558 return (TREE_OPERAND (exp, 1) != 0
2559 && contains_placeholder_p (TREE_OPERAND (exp, 1)));
2565 switch (tree_code_length[(int) code])
2568 return contains_placeholder_p (TREE_OPERAND (exp, 0));
2570 return (contains_placeholder_p (TREE_OPERAND (exp, 0))
2571 || contains_placeholder_p (TREE_OPERAND (exp, 1)));
2581 /* Given a tree EXP, a FIELD_DECL F, and a replacement value R,
2582 return a tree with all occurrences of references to F in a
2583 PLACEHOLDER_EXPR replaced by R. Note that we assume here that EXP
2584 contains only arithmetic expressions or a CALL_EXPR with a
2585 PLACEHOLDER_EXPR occurring only in its arglist. */
2588 substitute_in_expr (exp, f, r)
2593 enum tree_code code = TREE_CODE (exp);
2598 switch (TREE_CODE_CLASS (code))
2605 if (code == PLACEHOLDER_EXPR)
2607 else if (code == TREE_LIST)
2609 op0 = (TREE_CHAIN (exp) == 0
2610 ? 0 : substitute_in_expr (TREE_CHAIN (exp), f, r));
2611 op1 = substitute_in_expr (TREE_VALUE (exp), f, r);
2612 if (op0 == TREE_CHAIN (exp) && op1 == TREE_VALUE (exp))
2615 return tree_cons (TREE_PURPOSE (exp), op1, op0);
2624 switch (tree_code_length[(int) code])
2627 op0 = substitute_in_expr (TREE_OPERAND (exp, 0), f, r);
2628 if (op0 == TREE_OPERAND (exp, 0))
2631 new = fold (build1 (code, TREE_TYPE (exp), op0));
2635 /* An RTL_EXPR cannot contain a PLACEHOLDER_EXPR; a CONSTRUCTOR
2636 could, but we don't support it. */
2637 if (code == RTL_EXPR)
2639 else if (code == CONSTRUCTOR)
2642 op0 = substitute_in_expr (TREE_OPERAND (exp, 0), f, r);
2643 op1 = substitute_in_expr (TREE_OPERAND (exp, 1), f, r);
2644 if (op0 == TREE_OPERAND (exp, 0) && op1 == TREE_OPERAND (exp, 1))
2647 new = fold (build (code, TREE_TYPE (exp), op0, op1));
2651 /* It cannot be that anything inside a SAVE_EXPR contains a
2652 PLACEHOLDER_EXPR. */
2653 if (code == SAVE_EXPR)
2656 else if (code == CALL_EXPR)
2658 op1 = substitute_in_expr (TREE_OPERAND (exp, 1), f, r);
2659 if (op1 == TREE_OPERAND (exp, 1))
2662 return build (code, TREE_TYPE (exp),
2663 TREE_OPERAND (exp, 0), op1, NULL_TREE);
2666 else if (code != COND_EXPR)
2669 op0 = substitute_in_expr (TREE_OPERAND (exp, 0), f, r);
2670 op1 = substitute_in_expr (TREE_OPERAND (exp, 1), f, r);
2671 op2 = substitute_in_expr (TREE_OPERAND (exp, 2), f, r);
2672 if (op0 == TREE_OPERAND (exp, 0) && op1 == TREE_OPERAND (exp, 1)
2673 && op2 == TREE_OPERAND (exp, 2))
2676 new = fold (build (code, TREE_TYPE (exp), op0, op1, op2));
2689 /* If this expression is getting a value from a PLACEHOLDER_EXPR
2690 and it is the right field, replace it with R. */
2691 for (inner = TREE_OPERAND (exp, 0);
2692 TREE_CODE_CLASS (TREE_CODE (inner)) == 'r';
2693 inner = TREE_OPERAND (inner, 0))
2695 if (TREE_CODE (inner) == PLACEHOLDER_EXPR
2696 && TREE_OPERAND (exp, 1) == f)
2699 /* If this expression hasn't been completed let, leave it
2701 if (TREE_CODE (inner) == PLACEHOLDER_EXPR
2702 && TREE_TYPE (inner) == 0)
2705 op0 = substitute_in_expr (TREE_OPERAND (exp, 0), f, r);
2706 if (op0 == TREE_OPERAND (exp, 0))
2709 new = fold (build (code, TREE_TYPE (exp), op0,
2710 TREE_OPERAND (exp, 1)));
2714 op0 = substitute_in_expr (TREE_OPERAND (exp, 0), f, r);
2715 op1 = substitute_in_expr (TREE_OPERAND (exp, 1), f, r);
2716 op2 = substitute_in_expr (TREE_OPERAND (exp, 2), f, r);
2717 if (op0 == TREE_OPERAND (exp, 0) && op1 == TREE_OPERAND (exp, 1)
2718 && op2 == TREE_OPERAND (exp, 2))
2721 new = fold (build (code, TREE_TYPE (exp), op0, op1, op2));
2726 op0 = substitute_in_expr (TREE_OPERAND (exp, 0), f, r);
2727 if (op0 == TREE_OPERAND (exp, 0))
2730 new = fold (build1 (code, TREE_TYPE (exp), op0));
2742 TREE_READONLY (new) = TREE_READONLY (exp);
2746 /* Stabilize a reference so that we can use it any number of times
2747 without causing its operands to be evaluated more than once.
2748 Returns the stabilized reference. This works by means of save_expr,
2749 so see the caveats in the comments about save_expr.
2751 Also allows conversion expressions whose operands are references.
2752 Any other kind of expression is returned unchanged. */
2755 stabilize_reference (ref)
2758 register tree result;
2759 register enum tree_code code = TREE_CODE (ref);
2766 /* No action is needed in this case. */
2772 case FIX_TRUNC_EXPR:
2773 case FIX_FLOOR_EXPR:
2774 case FIX_ROUND_EXPR:
2776 result = build_nt (code, stabilize_reference (TREE_OPERAND (ref, 0)));
2780 result = build_nt (INDIRECT_REF,
2781 stabilize_reference_1 (TREE_OPERAND (ref, 0)));
2785 result = build_nt (COMPONENT_REF,
2786 stabilize_reference (TREE_OPERAND (ref, 0)),
2787 TREE_OPERAND (ref, 1));
2791 result = build_nt (BIT_FIELD_REF,
2792 stabilize_reference (TREE_OPERAND (ref, 0)),
2793 stabilize_reference_1 (TREE_OPERAND (ref, 1)),
2794 stabilize_reference_1 (TREE_OPERAND (ref, 2)));
2798 result = build_nt (ARRAY_REF,
2799 stabilize_reference (TREE_OPERAND (ref, 0)),
2800 stabilize_reference_1 (TREE_OPERAND (ref, 1)));
2804 /* We cannot wrap the first expression in a SAVE_EXPR, as then
2805 it wouldn't be ignored. This matters when dealing with
2807 return stabilize_reference_1 (ref);
2810 result = build1 (INDIRECT_REF, TREE_TYPE (ref),
2811 save_expr (build1 (ADDR_EXPR,
2812 build_pointer_type (TREE_TYPE (ref)),
2817 /* If arg isn't a kind of lvalue we recognize, make no change.
2818 Caller should recognize the error for an invalid lvalue. */
2823 return error_mark_node;
2826 TREE_TYPE (result) = TREE_TYPE (ref);
2827 TREE_READONLY (result) = TREE_READONLY (ref);
2828 TREE_SIDE_EFFECTS (result) = TREE_SIDE_EFFECTS (ref);
2829 TREE_THIS_VOLATILE (result) = TREE_THIS_VOLATILE (ref);
2830 TREE_RAISES (result) = TREE_RAISES (ref);
2835 /* Subroutine of stabilize_reference; this is called for subtrees of
2836 references. Any expression with side-effects must be put in a SAVE_EXPR
2837 to ensure that it is only evaluated once.
2839 We don't put SAVE_EXPR nodes around everything, because assigning very
2840 simple expressions to temporaries causes us to miss good opportunities
2841 for optimizations. Among other things, the opportunity to fold in the
2842 addition of a constant into an addressing mode often gets lost, e.g.
2843 "y[i+1] += x;". In general, we take the approach that we should not make
2844 an assignment unless we are forced into it - i.e., that any non-side effect
2845 operator should be allowed, and that cse should take care of coalescing
2846 multiple utterances of the same expression should that prove fruitful. */
2849 stabilize_reference_1 (e)
2852 register tree result;
2853 register enum tree_code code = TREE_CODE (e);
2855 /* We cannot ignore const expressions because it might be a reference
2856 to a const array but whose index contains side-effects. But we can
2857 ignore things that are actual constant or that already have been
2858 handled by this function. */
2860 if (TREE_CONSTANT (e) || code == SAVE_EXPR)
2863 switch (TREE_CODE_CLASS (code))
2873 /* If the expression has side-effects, then encase it in a SAVE_EXPR
2874 so that it will only be evaluated once. */
2875 /* The reference (r) and comparison (<) classes could be handled as
2876 below, but it is generally faster to only evaluate them once. */
2877 if (TREE_SIDE_EFFECTS (e))
2878 return save_expr (e);
2882 /* Constants need no processing. In fact, we should never reach
2887 /* Division is slow and tends to be compiled with jumps,
2888 especially the division by powers of 2 that is often
2889 found inside of an array reference. So do it just once. */
2890 if (code == TRUNC_DIV_EXPR || code == TRUNC_MOD_EXPR
2891 || code == FLOOR_DIV_EXPR || code == FLOOR_MOD_EXPR
2892 || code == CEIL_DIV_EXPR || code == CEIL_MOD_EXPR
2893 || code == ROUND_DIV_EXPR || code == ROUND_MOD_EXPR)
2894 return save_expr (e);
2895 /* Recursively stabilize each operand. */
2896 result = build_nt (code, stabilize_reference_1 (TREE_OPERAND (e, 0)),
2897 stabilize_reference_1 (TREE_OPERAND (e, 1)));
2901 /* Recursively stabilize each operand. */
2902 result = build_nt (code, stabilize_reference_1 (TREE_OPERAND (e, 0)));
2909 TREE_TYPE (result) = TREE_TYPE (e);
2910 TREE_READONLY (result) = TREE_READONLY (e);
2911 TREE_SIDE_EFFECTS (result) = TREE_SIDE_EFFECTS (e);
2912 TREE_THIS_VOLATILE (result) = TREE_THIS_VOLATILE (e);
2913 TREE_RAISES (result) = TREE_RAISES (e);
2918 /* Low-level constructors for expressions. */
2920 /* Build an expression of code CODE, data type TYPE,
2921 and operands as specified by the arguments ARG1 and following arguments.
2922 Expressions and reference nodes can be created this way.
2923 Constants, decls, types and misc nodes cannot be. */
2926 build VPROTO((enum tree_code code, tree tt, ...))
2929 enum tree_code code;
2934 register int length;
2940 code = va_arg (p, enum tree_code);
2941 tt = va_arg (p, tree);
2944 t = make_node (code);
2945 length = tree_code_length[(int) code];
2950 /* This is equivalent to the loop below, but faster. */
2951 register tree arg0 = va_arg (p, tree);
2952 register tree arg1 = va_arg (p, tree);
2953 TREE_OPERAND (t, 0) = arg0;
2954 TREE_OPERAND (t, 1) = arg1;
2955 if ((arg0 && TREE_SIDE_EFFECTS (arg0))
2956 || (arg1 && TREE_SIDE_EFFECTS (arg1)))
2957 TREE_SIDE_EFFECTS (t) = 1;
2959 = (arg0 && TREE_RAISES (arg0)) || (arg1 && TREE_RAISES (arg1));
2961 else if (length == 1)
2963 register tree arg0 = va_arg (p, tree);
2965 /* Call build1 for this! */
2966 if (TREE_CODE_CLASS (code) != 's')
2968 TREE_OPERAND (t, 0) = arg0;
2969 if (arg0 && TREE_SIDE_EFFECTS (arg0))
2970 TREE_SIDE_EFFECTS (t) = 1;
2971 TREE_RAISES (t) = (arg0 && TREE_RAISES (arg0));
2975 for (i = 0; i < length; i++)
2977 register tree operand = va_arg (p, tree);
2978 TREE_OPERAND (t, i) = operand;
2981 if (TREE_SIDE_EFFECTS (operand))
2982 TREE_SIDE_EFFECTS (t) = 1;
2983 if (TREE_RAISES (operand))
2984 TREE_RAISES (t) = 1;
2992 /* Same as above, but only builds for unary operators.
2993 Saves lions share of calls to `build'; cuts down use
2994 of varargs, which is expensive for RISC machines. */
2997 build1 (code, type, node)
2998 enum tree_code code;
3002 register struct obstack *obstack = expression_obstack;
3003 register int i, length;
3004 register tree_node_kind kind;
3007 #ifdef GATHER_STATISTICS
3008 if (TREE_CODE_CLASS (code) == 'r')
3014 length = sizeof (struct tree_exp);
3016 t = (tree) obstack_alloc (obstack, length);
3018 #ifdef GATHER_STATISTICS
3019 tree_node_counts[(int)kind]++;
3020 tree_node_sizes[(int)kind] += length;
3023 for (i = (length / sizeof (int)) - 1; i >= 0; i--)
3026 TREE_TYPE (t) = type;
3027 TREE_SET_CODE (t, code);
3029 if (obstack == &permanent_obstack)
3030 TREE_PERMANENT (t) = 1;
3032 TREE_OPERAND (t, 0) = node;
3035 if (TREE_SIDE_EFFECTS (node))
3036 TREE_SIDE_EFFECTS (t) = 1;
3037 if (TREE_RAISES (node))
3038 TREE_RAISES (t) = 1;
3044 /* Similar except don't specify the TREE_TYPE
3045 and leave the TREE_SIDE_EFFECTS as 0.
3046 It is permissible for arguments to be null,
3047 or even garbage if their values do not matter. */
3050 build_nt VPROTO((enum tree_code code, ...))
3053 enum tree_code code;
3057 register int length;
3063 code = va_arg (p, enum tree_code);
3066 t = make_node (code);
3067 length = tree_code_length[(int) code];
3069 for (i = 0; i < length; i++)
3070 TREE_OPERAND (t, i) = va_arg (p, tree);
3076 /* Similar to `build_nt', except we build
3077 on the temp_decl_obstack, regardless. */
3080 build_parse_node VPROTO((enum tree_code code, ...))
3083 enum tree_code code;
3085 register struct obstack *ambient_obstack = expression_obstack;
3088 register int length;
3094 code = va_arg (p, enum tree_code);
3097 expression_obstack = &temp_decl_obstack;
3099 t = make_node (code);
3100 length = tree_code_length[(int) code];
3102 for (i = 0; i < length; i++)
3103 TREE_OPERAND (t, i) = va_arg (p, tree);
3106 expression_obstack = ambient_obstack;
3111 /* Commented out because this wants to be done very
3112 differently. See cp-lex.c. */
3114 build_op_identifier (op1, op2)
3117 register tree t = make_node (OP_IDENTIFIER);
3118 TREE_PURPOSE (t) = op1;
3119 TREE_VALUE (t) = op2;
3124 /* Create a DECL_... node of code CODE, name NAME and data type TYPE.
3125 We do NOT enter this node in any sort of symbol table.
3127 layout_decl is used to set up the decl's storage layout.
3128 Other slots are initialized to 0 or null pointers. */
3131 build_decl (code, name, type)
3132 enum tree_code code;
3137 t = make_node (code);
3139 /* if (type == error_mark_node)
3140 type = integer_type_node; */
3141 /* That is not done, deliberately, so that having error_mark_node
3142 as the type can suppress useless errors in the use of this variable. */
3144 DECL_NAME (t) = name;
3145 DECL_ASSEMBLER_NAME (t) = name;
3146 TREE_TYPE (t) = type;
3148 if (code == VAR_DECL || code == PARM_DECL || code == RESULT_DECL)
3150 else if (code == FUNCTION_DECL)
3151 DECL_MODE (t) = FUNCTION_MODE;
3156 /* BLOCK nodes are used to represent the structure of binding contours
3157 and declarations, once those contours have been exited and their contents
3158 compiled. This information is used for outputting debugging info. */
3161 build_block (vars, tags, subblocks, supercontext, chain)
3162 tree vars, tags, subblocks, supercontext, chain;
3164 register tree block = make_node (BLOCK);
3165 BLOCK_VARS (block) = vars;
3166 BLOCK_TYPE_TAGS (block) = tags;
3167 BLOCK_SUBBLOCKS (block) = subblocks;
3168 BLOCK_SUPERCONTEXT (block) = supercontext;
3169 BLOCK_CHAIN (block) = chain;
3173 /* Return a declaration like DDECL except that its DECL_MACHINE_ATTRIBUTE
3177 build_decl_attribute_variant (ddecl, attribute)
3178 tree ddecl, attribute;
3180 DECL_MACHINE_ATTRIBUTES (ddecl) = attribute;
3184 /* Return a type like TTYPE except that its TYPE_ATTRIBUTE
3187 Record such modified types already made so we don't make duplicates. */
3190 build_type_attribute_variant (ttype, attribute)
3191 tree ttype, attribute;
3193 if ( ! attribute_list_equal (TYPE_ATTRIBUTES (ttype), attribute))
3195 register int hashcode;
3196 register struct obstack *ambient_obstack = current_obstack;
3199 if (ambient_obstack != &permanent_obstack)
3200 current_obstack = TYPE_OBSTACK (ttype);
3202 ntype = copy_node (ttype);
3203 current_obstack = ambient_obstack;
3205 TYPE_POINTER_TO (ntype) = 0;
3206 TYPE_REFERENCE_TO (ntype) = 0;
3207 TYPE_ATTRIBUTES (ntype) = attribute;
3209 /* Create a new main variant of TYPE. */
3210 TYPE_MAIN_VARIANT (ntype) = ntype;
3211 TYPE_NEXT_VARIANT (ntype) = 0;
3212 TYPE_READONLY (ntype) = TYPE_VOLATILE (ntype) = 0;
3214 hashcode = TYPE_HASH (TREE_CODE (ntype))
3215 + TYPE_HASH (TREE_TYPE (ntype))
3216 + attribute_hash_list (attribute);
3218 switch (TREE_CODE (ntype))
3221 hashcode += TYPE_HASH (TYPE_ARG_TYPES (ntype));
3224 hashcode += TYPE_HASH (TYPE_DOMAIN (ntype));
3227 hashcode += TYPE_HASH (TYPE_MAX_VALUE (ntype));
3230 hashcode += TYPE_HASH (TYPE_PRECISION (ntype));
3236 ntype = type_hash_canon (hashcode, ntype);
3237 ttype = build_type_variant (ntype, TYPE_READONLY (ttype),
3238 TYPE_VOLATILE (ttype));
3244 /* Return a 1 if ATTR_NAME and ATTR_ARGS is valid for either declaration DECL
3245 or type TYPE and 0 otherwise. Validity is determined the configuration
3246 macros VALID_MACHINE_DECL_ATTRIBUTE and VALID_MACHINE_TYPE_ATTRIBUTE. */
3249 valid_machine_attribute (attr_name, attr_args, decl, type)
3250 tree attr_name, attr_args;
3255 tree decl_attr_list = decl != 0 ? DECL_MACHINE_ATTRIBUTES (decl) : 0;
3256 tree type_attr_list = TYPE_ATTRIBUTES (type);
3258 if (TREE_CODE (attr_name) != IDENTIFIER_NODE)
3261 #ifdef VALID_MACHINE_DECL_ATTRIBUTE
3263 && VALID_MACHINE_DECL_ATTRIBUTE (decl, decl_attr_list, attr_name, attr_args))
3265 tree attr = lookup_attribute (IDENTIFIER_POINTER (attr_name),
3268 if (attr != NULL_TREE)
3270 /* Override existing arguments. Declarations are unique so we can
3271 modify this in place. */
3272 TREE_VALUE (attr) = attr_args;
3276 decl_attr_list = tree_cons (attr_name, attr_args, decl_attr_list);
3277 decl = build_decl_attribute_variant (decl, decl_attr_list);
3284 #ifdef VALID_MACHINE_TYPE_ATTRIBUTE
3285 if (VALID_MACHINE_TYPE_ATTRIBUTE (type, type_attr_list, attr_name, attr_args))
3287 tree attr = lookup_attribute (IDENTIFIER_POINTER (attr_name),
3290 if (attr != NULL_TREE)
3292 /* Override existing arguments.
3293 ??? This currently works since attribute arguments are not
3294 included in `attribute_hash_list'. Something more complicated
3295 may be needed in the future. */
3296 TREE_VALUE (attr) = attr_args;
3300 type_attr_list = tree_cons (attr_name, attr_args, type_attr_list);
3301 type = build_type_attribute_variant (type, type_attr_list);
3304 TREE_TYPE (decl) = type;
3308 /* Handle putting a type attribute on pointer-to-function-type by putting
3309 the attribute on the function type. */
3310 else if (TREE_CODE (type) == POINTER_TYPE
3311 && TREE_CODE (TREE_TYPE (type)) == FUNCTION_TYPE
3312 && VALID_MACHINE_TYPE_ATTRIBUTE (TREE_TYPE (type), type_attr_list,
3313 attr_name, attr_args))
3315 tree inner_type = TREE_TYPE (type);
3316 tree inner_attr_list = TYPE_ATTRIBUTES (inner_type);
3317 tree attr = lookup_attribute (IDENTIFIER_POINTER (attr_name),
3320 if (attr != NULL_TREE)
3321 TREE_VALUE (attr) = attr_args;
3324 inner_attr_list = tree_cons (attr_name, attr_args, inner_attr_list);
3325 inner_type = build_type_attribute_variant (inner_type,
3330 TREE_TYPE (decl) = build_pointer_type (inner_type);
3339 /* Return non-zero if IDENT is a valid name for attribute ATTR,
3342 We try both `text' and `__text__', ATTR may be either one. */
3343 /* ??? It might be a reasonable simplification to require ATTR to be only
3344 `text'. One might then also require attribute lists to be stored in
3345 their canonicalized form. */
3348 is_attribute_p (attr, ident)
3352 int ident_len, attr_len;
3355 if (TREE_CODE (ident) != IDENTIFIER_NODE)
3358 if (strcmp (attr, IDENTIFIER_POINTER (ident)) == 0)
3361 p = IDENTIFIER_POINTER (ident);
3362 ident_len = strlen (p);
3363 attr_len = strlen (attr);
3365 /* If ATTR is `__text__', IDENT must be `text'; and vice versa. */
3369 || attr[attr_len - 2] != '_'
3370 || attr[attr_len - 1] != '_')
3372 if (ident_len == attr_len - 4
3373 && strncmp (attr + 2, p, attr_len - 4) == 0)
3378 if (ident_len == attr_len + 4
3379 && p[0] == '_' && p[1] == '_'
3380 && p[ident_len - 2] == '_' && p[ident_len - 1] == '_'
3381 && strncmp (attr, p + 2, attr_len) == 0)
3388 /* Given an attribute name and a list of attributes, return a pointer to the
3389 attribute's list element if the attribute is part of the list, or NULL_TREE
3393 lookup_attribute (attr_name, list)
3399 for (l = list; l; l = TREE_CHAIN (l))
3401 if (TREE_CODE (TREE_PURPOSE (l)) != IDENTIFIER_NODE)
3403 if (is_attribute_p (attr_name, TREE_PURPOSE (l)))
3410 /* Return an attribute list that is the union of a1 and a2. */
3413 merge_attributes (a1, a2)
3414 register tree a1, a2;
3418 /* Either one unset? Take the set one. */
3420 if (! (attributes = a1))
3423 /* One that completely contains the other? Take it. */
3425 else if (a2 && ! attribute_list_contained (a1, a2))
3426 if (attribute_list_contained (a2, a1))
3430 /* Pick the longest list, and hang on the other list. */
3431 /* ??? For the moment we punt on the issue of attrs with args. */
3433 if (list_length (a1) < list_length (a2))
3434 attributes = a2, a2 = a1;
3436 for (; a2; a2 = TREE_CHAIN (a2))
3437 if (lookup_attribute (IDENTIFIER_POINTER (TREE_PURPOSE (a2)),
3438 attributes) == NULL_TREE)
3440 a1 = copy_node (a2);
3441 TREE_CHAIN (a1) = attributes;
3448 /* Return a type like TYPE except that its TYPE_READONLY is CONSTP
3449 and its TYPE_VOLATILE is VOLATILEP.
3451 Such variant types already made are recorded so that duplicates
3454 A variant types should never be used as the type of an expression.
3455 Always copy the variant information into the TREE_READONLY
3456 and TREE_THIS_VOLATILE of the expression, and then give the expression
3457 as its type the "main variant", the variant whose TYPE_READONLY
3458 and TYPE_VOLATILE are zero. Use TYPE_MAIN_VARIANT to find the
3462 build_type_variant (type, constp, volatilep)
3464 int constp, volatilep;
3468 /* Treat any nonzero argument as 1. */
3470 volatilep = !!volatilep;
3472 /* Search the chain of variants to see if there is already one there just
3473 like the one we need to have. If so, use that existing one. We must
3474 preserve the TYPE_NAME, since there is code that depends on this. */
3476 for (t = TYPE_MAIN_VARIANT (type); t; t = TYPE_NEXT_VARIANT (t))
3477 if (constp == TYPE_READONLY (t) && volatilep == TYPE_VOLATILE (t)
3478 && TYPE_NAME (t) == TYPE_NAME (type))
3481 /* We need a new one. */
3483 t = build_type_copy (type);
3484 TYPE_READONLY (t) = constp;
3485 TYPE_VOLATILE (t) = volatilep;
3490 /* Create a new variant of TYPE, equivalent but distinct.
3491 This is so the caller can modify it. */
3494 build_type_copy (type)
3497 register tree t, m = TYPE_MAIN_VARIANT (type);
3498 register struct obstack *ambient_obstack = current_obstack;
3500 current_obstack = TYPE_OBSTACK (type);
3501 t = copy_node (type);
3502 current_obstack = ambient_obstack;
3504 TYPE_POINTER_TO (t) = 0;
3505 TYPE_REFERENCE_TO (t) = 0;
3507 /* Add this type to the chain of variants of TYPE. */
3508 TYPE_NEXT_VARIANT (t) = TYPE_NEXT_VARIANT (m);
3509 TYPE_NEXT_VARIANT (m) = t;
3514 /* Hashing of types so that we don't make duplicates.
3515 The entry point is `type_hash_canon'. */
3517 /* Each hash table slot is a bucket containing a chain
3518 of these structures. */
3522 struct type_hash *next; /* Next structure in the bucket. */
3523 int hashcode; /* Hash code of this type. */
3524 tree type; /* The type recorded here. */
3527 /* Now here is the hash table. When recording a type, it is added
3528 to the slot whose index is the hash code mod the table size.
3529 Note that the hash table is used for several kinds of types
3530 (function types, array types and array index range types, for now).
3531 While all these live in the same table, they are completely independent,
3532 and the hash code is computed differently for each of these. */
3534 #define TYPE_HASH_SIZE 59
3535 struct type_hash *type_hash_table[TYPE_HASH_SIZE];
3537 /* Compute a hash code for a list of types (chain of TREE_LIST nodes
3538 with types in the TREE_VALUE slots), by adding the hash codes
3539 of the individual types. */
3542 type_hash_list (list)
3545 register int hashcode;
3547 for (hashcode = 0, tail = list; tail; tail = TREE_CHAIN (tail))
3548 hashcode += TYPE_HASH (TREE_VALUE (tail));
3552 /* Look in the type hash table for a type isomorphic to TYPE.
3553 If one is found, return it. Otherwise return 0. */
3556 type_hash_lookup (hashcode, type)
3560 register struct type_hash *h;
3561 for (h = type_hash_table[hashcode % TYPE_HASH_SIZE]; h; h = h->next)
3562 if (h->hashcode == hashcode
3563 && TREE_CODE (h->type) == TREE_CODE (type)
3564 && TREE_TYPE (h->type) == TREE_TYPE (type)
3565 && attribute_list_equal (TYPE_ATTRIBUTES (h->type),
3566 TYPE_ATTRIBUTES (type))
3567 && (TYPE_MAX_VALUE (h->type) == TYPE_MAX_VALUE (type)
3568 || tree_int_cst_equal (TYPE_MAX_VALUE (h->type),
3569 TYPE_MAX_VALUE (type)))
3570 && (TYPE_MIN_VALUE (h->type) == TYPE_MIN_VALUE (type)
3571 || tree_int_cst_equal (TYPE_MIN_VALUE (h->type),
3572 TYPE_MIN_VALUE (type)))
3573 /* Note that TYPE_DOMAIN is TYPE_ARG_TYPES for FUNCTION_TYPE. */
3574 && (TYPE_DOMAIN (h->type) == TYPE_DOMAIN (type)
3575 || (TYPE_DOMAIN (h->type)
3576 && TREE_CODE (TYPE_DOMAIN (h->type)) == TREE_LIST
3577 && TYPE_DOMAIN (type)
3578 && TREE_CODE (TYPE_DOMAIN (type)) == TREE_LIST
3579 && type_list_equal (TYPE_DOMAIN (h->type),
3580 TYPE_DOMAIN (type)))))
3585 /* Add an entry to the type-hash-table
3586 for a type TYPE whose hash code is HASHCODE. */
3589 type_hash_add (hashcode, type)
3593 register struct type_hash *h;
3595 h = (struct type_hash *) oballoc (sizeof (struct type_hash));
3596 h->hashcode = hashcode;
3598 h->next = type_hash_table[hashcode % TYPE_HASH_SIZE];
3599 type_hash_table[hashcode % TYPE_HASH_SIZE] = h;
3602 /* Given TYPE, and HASHCODE its hash code, return the canonical
3603 object for an identical type if one already exists.
3604 Otherwise, return TYPE, and record it as the canonical object
3605 if it is a permanent object.
3607 To use this function, first create a type of the sort you want.
3608 Then compute its hash code from the fields of the type that
3609 make it different from other similar types.
3610 Then call this function and use the value.
3611 This function frees the type you pass in if it is a duplicate. */
3613 /* Set to 1 to debug without canonicalization. Never set by program. */
3614 int debug_no_type_hash = 0;
3617 type_hash_canon (hashcode, type)
3623 if (debug_no_type_hash)
3626 t1 = type_hash_lookup (hashcode, type);
3629 obstack_free (TYPE_OBSTACK (type), type);
3630 #ifdef GATHER_STATISTICS
3631 tree_node_counts[(int)t_kind]--;
3632 tree_node_sizes[(int)t_kind] -= sizeof (struct tree_type);
3637 /* If this is a permanent type, record it for later reuse. */
3638 if (TREE_PERMANENT (type))
3639 type_hash_add (hashcode, type);
3644 /* Compute a hash code for a list of attributes (chain of TREE_LIST nodes
3645 with names in the TREE_PURPOSE slots and args in the TREE_VALUE slots),
3646 by adding the hash codes of the individual attributes. */
3649 attribute_hash_list (list)
3652 register int hashcode;
3654 for (hashcode = 0, tail = list; tail; tail = TREE_CHAIN (tail))
3655 /* ??? Do we want to add in TREE_VALUE too? */
3656 hashcode += TYPE_HASH (TREE_PURPOSE (tail));
3660 /* Given two lists of attributes, return true if list l2 is
3661 equivalent to l1. */
3664 attribute_list_equal (l1, l2)
3667 return attribute_list_contained (l1, l2)
3668 && attribute_list_contained (l2, l1);
3671 /* Given two lists of attributes, return true if list L2 is
3672 completely contained within L1. */
3673 /* ??? This would be faster if attribute names were stored in a canonicalized
3674 form. Otherwise, if L1 uses `foo' and L2 uses `__foo__', the long method
3675 must be used to show these elements are equivalent (which they are). */
3676 /* ??? It's not clear that attributes with arguments will always be handled
3680 attribute_list_contained (l1, l2)
3683 register tree t1, t2;
3685 /* First check the obvious, maybe the lists are identical. */
3689 /* Maybe the lists are similar. */
3690 for (t1 = l1, t2 = l2;
3692 && TREE_PURPOSE (t1) == TREE_PURPOSE (t2)
3693 && TREE_VALUE (t1) == TREE_VALUE (t2);
3694 t1 = TREE_CHAIN (t1), t2 = TREE_CHAIN (t2));
3696 /* Maybe the lists are equal. */
3697 if (t1 == 0 && t2 == 0)
3700 for (; t2; t2 = TREE_CHAIN (t2))
3703 = lookup_attribute (IDENTIFIER_POINTER (TREE_PURPOSE (t2)), l1);
3705 if (attr == NULL_TREE)
3707 if (simple_cst_equal (TREE_VALUE (t2), TREE_VALUE (attr)) != 1)
3714 /* Given two lists of types
3715 (chains of TREE_LIST nodes with types in the TREE_VALUE slots)
3716 return 1 if the lists contain the same types in the same order.
3717 Also, the TREE_PURPOSEs must match. */
3720 type_list_equal (l1, l2)
3723 register tree t1, t2;
3725 for (t1 = l1, t2 = l2; t1 && t2; t1 = TREE_CHAIN (t1), t2 = TREE_CHAIN (t2))
3726 if (TREE_VALUE (t1) != TREE_VALUE (t2)
3727 || (TREE_PURPOSE (t1) != TREE_PURPOSE (t2)
3728 && ! (1 == simple_cst_equal (TREE_PURPOSE (t1), TREE_PURPOSE (t2))
3729 && (TREE_TYPE (TREE_PURPOSE (t1))
3730 == TREE_TYPE (TREE_PURPOSE (t2))))))
3736 /* Nonzero if integer constants T1 and T2
3737 represent the same constant value. */
3740 tree_int_cst_equal (t1, t2)
3745 if (t1 == 0 || t2 == 0)
3747 if (TREE_CODE (t1) == INTEGER_CST
3748 && TREE_CODE (t2) == INTEGER_CST
3749 && TREE_INT_CST_LOW (t1) == TREE_INT_CST_LOW (t2)
3750 && TREE_INT_CST_HIGH (t1) == TREE_INT_CST_HIGH (t2))
3755 /* Nonzero if integer constants T1 and T2 represent values that satisfy <.
3756 The precise way of comparison depends on their data type. */
3759 tree_int_cst_lt (t1, t2)
3765 if (!TREE_UNSIGNED (TREE_TYPE (t1)))
3766 return INT_CST_LT (t1, t2);
3767 return INT_CST_LT_UNSIGNED (t1, t2);
3770 /* Return an indication of the sign of the integer constant T.
3771 The return value is -1 if T < 0, 0 if T == 0, and 1 if T > 0.
3772 Note that -1 will never be returned it T's type is unsigned. */
3775 tree_int_cst_sgn (t)
3778 if (TREE_INT_CST_LOW (t) == 0 && TREE_INT_CST_HIGH (t) == 0)
3780 else if (TREE_UNSIGNED (TREE_TYPE (t)))
3782 else if (TREE_INT_CST_HIGH (t) < 0)
3788 /* Compare two constructor-element-type constants. Return 1 if the lists
3789 are known to be equal; otherwise return 0. */
3792 simple_cst_list_equal (l1, l2)
3795 while (l1 != NULL_TREE && l2 != NULL_TREE)
3797 if (simple_cst_equal (TREE_VALUE (l1), TREE_VALUE (l2)) != 1)
3800 l1 = TREE_CHAIN (l1);
3801 l2 = TREE_CHAIN (l2);
3807 /* Return truthvalue of whether T1 is the same tree structure as T2.
3808 Return 1 if they are the same.
3809 Return 0 if they are understandably different.
3810 Return -1 if either contains tree structure not understood by
3814 simple_cst_equal (t1, t2)
3817 register enum tree_code code1, code2;
3822 if (t1 == 0 || t2 == 0)
3825 code1 = TREE_CODE (t1);
3826 code2 = TREE_CODE (t2);
3828 if (code1 == NOP_EXPR || code1 == CONVERT_EXPR || code1 == NON_LVALUE_EXPR)
3829 if (code2 == NOP_EXPR || code2 == CONVERT_EXPR || code2 == NON_LVALUE_EXPR)
3830 return simple_cst_equal (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0));
3832 return simple_cst_equal (TREE_OPERAND (t1, 0), t2);
3833 else if (code2 == NOP_EXPR || code2 == CONVERT_EXPR
3834 || code2 == NON_LVALUE_EXPR)
3835 return simple_cst_equal (t1, TREE_OPERAND (t2, 0));
3843 return TREE_INT_CST_LOW (t1) == TREE_INT_CST_LOW (t2)
3844 && TREE_INT_CST_HIGH (t1) == TREE_INT_CST_HIGH (t2);
3847 return REAL_VALUES_IDENTICAL (TREE_REAL_CST (t1), TREE_REAL_CST (t2));
3850 return TREE_STRING_LENGTH (t1) == TREE_STRING_LENGTH (t2)
3851 && !bcmp (TREE_STRING_POINTER (t1), TREE_STRING_POINTER (t2),
3852 TREE_STRING_LENGTH (t1));
3858 return simple_cst_equal (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0));
3861 cmp = simple_cst_equal (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0));
3864 return simple_cst_list_equal (TREE_OPERAND (t1, 1), TREE_OPERAND (t2, 1));
3867 /* Special case: if either target is an unallocated VAR_DECL,
3868 it means that it's going to be unified with whatever the
3869 TARGET_EXPR is really supposed to initialize, so treat it
3870 as being equivalent to anything. */
3871 if ((TREE_CODE (TREE_OPERAND (t1, 0)) == VAR_DECL
3872 && DECL_NAME (TREE_OPERAND (t1, 0)) == NULL_TREE
3873 && DECL_RTL (TREE_OPERAND (t1, 0)) == 0)
3874 || (TREE_CODE (TREE_OPERAND (t2, 0)) == VAR_DECL
3875 && DECL_NAME (TREE_OPERAND (t2, 0)) == NULL_TREE
3876 && DECL_RTL (TREE_OPERAND (t2, 0)) == 0))
3879 cmp = simple_cst_equal (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0));
3882 return simple_cst_equal (TREE_OPERAND (t1, 1), TREE_OPERAND (t2, 1));
3884 case WITH_CLEANUP_EXPR:
3885 cmp = simple_cst_equal (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0));
3888 return simple_cst_equal (TREE_OPERAND (t1, 2), TREE_OPERAND (t1, 2));
3891 if (TREE_OPERAND (t1, 1) == TREE_OPERAND (t2, 1))
3892 return simple_cst_equal (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0));
3905 /* This general rule works for most tree codes. All exceptions should be
3906 handled above. If this is a language-specific tree code, we can't
3907 trust what might be in the operand, so say we don't know
3910 >= sizeof standard_tree_code_type / sizeof standard_tree_code_type[0])
3913 switch (TREE_CODE_CLASS (code1))
3923 for (i=0; i<tree_code_length[(int) code1]; ++i)
3925 cmp = simple_cst_equal (TREE_OPERAND (t1, i), TREE_OPERAND (t2, i));
3936 /* Constructors for pointer, array and function types.
3937 (RECORD_TYPE, UNION_TYPE and ENUMERAL_TYPE nodes are
3938 constructed by language-dependent code, not here.) */
3940 /* Construct, lay out and return the type of pointers to TO_TYPE.
3941 If such a type has already been constructed, reuse it. */
3944 build_pointer_type (to_type)
3947 register tree t = TYPE_POINTER_TO (to_type);
3949 /* First, if we already have a type for pointers to TO_TYPE, use it. */
3954 /* We need a new one. Put this in the same obstack as TO_TYPE. */
3955 push_obstacks (TYPE_OBSTACK (to_type), TYPE_OBSTACK (to_type));
3956 t = make_node (POINTER_TYPE);
3959 TREE_TYPE (t) = to_type;
3961 /* Record this type as the pointer to TO_TYPE. */
3962 TYPE_POINTER_TO (to_type) = t;
3964 /* Lay out the type. This function has many callers that are concerned
3965 with expression-construction, and this simplifies them all.
3966 Also, it guarantees the TYPE_SIZE is in the same obstack as the type. */
3972 /* Create a type of integers to be the TYPE_DOMAIN of an ARRAY_TYPE.
3973 MAXVAL should be the maximum value in the domain
3974 (one less than the length of the array).
3976 The maximum value that MAXVAL can have is INT_MAX for a HOST_WIDE_INT.
3977 We don't enforce this limit, that is up to caller (e.g. language front end).
3978 The limit exists because the result is a signed type and we don't handle
3979 sizes that use more than one HOST_WIDE_INT. */
3982 build_index_type (maxval)
3985 register tree itype = make_node (INTEGER_TYPE);
3987 TYPE_PRECISION (itype) = TYPE_PRECISION (sizetype);
3988 TYPE_MIN_VALUE (itype) = size_zero_node;
3990 push_obstacks (TYPE_OBSTACK (itype), TYPE_OBSTACK (itype));
3991 TYPE_MAX_VALUE (itype) = convert (sizetype, maxval);
3994 TYPE_MODE (itype) = TYPE_MODE (sizetype);
3995 TYPE_SIZE (itype) = TYPE_SIZE (sizetype);
3996 TYPE_ALIGN (itype) = TYPE_ALIGN (sizetype);
3997 if (TREE_CODE (maxval) == INTEGER_CST)
3999 int maxint = (int) TREE_INT_CST_LOW (maxval);
4000 /* If the domain should be empty, make sure the maxval
4001 remains -1 and is not spoiled by truncation. */
4002 if (INT_CST_LT (maxval, integer_zero_node))
4004 TYPE_MAX_VALUE (itype) = build_int_2 (-1, -1);
4005 TREE_TYPE (TYPE_MAX_VALUE (itype)) = sizetype;
4007 return type_hash_canon (maxint < 0 ? ~maxint : maxint, itype);
4013 /* Create a range of some discrete type TYPE (an INTEGER_TYPE,
4014 ENUMERAL_TYPE, BOOLEAN_TYPE, or CHAR_TYPE), with
4015 low bound LOWVAL and high bound HIGHVAL.
4016 if TYPE==NULL_TREE, sizetype is used. */
4019 build_range_type (type, lowval, highval)
4020 tree type, lowval, highval;
4022 register tree itype = make_node (INTEGER_TYPE);
4024 TREE_TYPE (itype) = type;
4025 if (type == NULL_TREE)
4028 push_obstacks (TYPE_OBSTACK (itype), TYPE_OBSTACK (itype));
4029 TYPE_MIN_VALUE (itype) = convert (type, lowval);
4030 TYPE_MAX_VALUE (itype) = convert (type, highval);
4033 TYPE_PRECISION (itype) = TYPE_PRECISION (type);
4034 TYPE_MODE (itype) = TYPE_MODE (type);
4035 TYPE_SIZE (itype) = TYPE_SIZE (type);
4036 TYPE_ALIGN (itype) = TYPE_ALIGN (type);
4037 if ((TREE_CODE (lowval) == INTEGER_CST)
4038 && (TREE_CODE (highval) == INTEGER_CST))
4040 HOST_WIDE_INT highint = TREE_INT_CST_LOW (highval);
4041 HOST_WIDE_INT lowint = TREE_INT_CST_LOW (lowval);
4042 int maxint = (int) (highint - lowint);
4043 return type_hash_canon (maxint < 0 ? ~maxint : maxint, itype);
4049 /* Just like build_index_type, but takes lowval and highval instead
4050 of just highval (maxval). */
4053 build_index_2_type (lowval,highval)
4054 tree lowval, highval;
4056 return build_range_type (NULL_TREE, lowval, highval);
4059 /* Return nonzero iff ITYPE1 and ITYPE2 are equal (in the LISP sense).
4060 Needed because when index types are not hashed, equal index types
4061 built at different times appear distinct, even though structurally,
4065 index_type_equal (itype1, itype2)
4066 tree itype1, itype2;
4068 if (TREE_CODE (itype1) != TREE_CODE (itype2))
4070 if (TREE_CODE (itype1) == INTEGER_TYPE)
4072 if (TYPE_PRECISION (itype1) != TYPE_PRECISION (itype2)
4073 || TYPE_MODE (itype1) != TYPE_MODE (itype2)
4074 || simple_cst_equal (TYPE_SIZE (itype1), TYPE_SIZE (itype2)) != 1
4075 || TYPE_ALIGN (itype1) != TYPE_ALIGN (itype2))
4077 if (1 == simple_cst_equal (TYPE_MIN_VALUE (itype1),
4078 TYPE_MIN_VALUE (itype2))
4079 && 1 == simple_cst_equal (TYPE_MAX_VALUE (itype1),
4080 TYPE_MAX_VALUE (itype2)))
4087 /* Construct, lay out and return the type of arrays of elements with ELT_TYPE
4088 and number of elements specified by the range of values of INDEX_TYPE.
4089 If such a type has already been constructed, reuse it. */
4092 build_array_type (elt_type, index_type)
4093 tree elt_type, index_type;
4098 if (TREE_CODE (elt_type) == FUNCTION_TYPE)
4100 error ("arrays of functions are not meaningful");
4101 elt_type = integer_type_node;
4104 /* Make sure TYPE_POINTER_TO (elt_type) is filled in. */
4105 build_pointer_type (elt_type);
4107 /* Allocate the array after the pointer type,
4108 in case we free it in type_hash_canon. */
4109 t = make_node (ARRAY_TYPE);
4110 TREE_TYPE (t) = elt_type;
4111 TYPE_DOMAIN (t) = index_type;
4113 if (index_type == 0)
4118 hashcode = TYPE_HASH (elt_type) + TYPE_HASH (index_type);
4119 t = type_hash_canon (hashcode, t);
4121 if (TYPE_SIZE (t) == 0)
4126 /* Construct, lay out and return
4127 the type of functions returning type VALUE_TYPE
4128 given arguments of types ARG_TYPES.
4129 ARG_TYPES is a chain of TREE_LIST nodes whose TREE_VALUEs
4130 are data type nodes for the arguments of the function.
4131 If such a type has already been constructed, reuse it. */
4134 build_function_type (value_type, arg_types)
4135 tree value_type, arg_types;
4140 if (TREE_CODE (value_type) == FUNCTION_TYPE)
4142 error ("function return type cannot be function");
4143 value_type = integer_type_node;
4146 /* Make a node of the sort we want. */
4147 t = make_node (FUNCTION_TYPE);
4148 TREE_TYPE (t) = value_type;
4149 TYPE_ARG_TYPES (t) = arg_types;
4151 /* If we already have such a type, use the old one and free this one. */
4152 hashcode = TYPE_HASH (value_type) + type_hash_list (arg_types);
4153 t = type_hash_canon (hashcode, t);
4155 if (TYPE_SIZE (t) == 0)
4160 /* Build the node for the type of references-to-TO_TYPE. */
4163 build_reference_type (to_type)
4166 register tree t = TYPE_REFERENCE_TO (to_type);
4167 register struct obstack *ambient_obstack = current_obstack;
4168 register struct obstack *ambient_saveable_obstack = saveable_obstack;
4170 /* First, if we already have a type for pointers to TO_TYPE, use it. */
4175 /* We need a new one. If TO_TYPE is permanent, make this permanent too. */
4176 if (TREE_PERMANENT (to_type))
4178 current_obstack = &permanent_obstack;
4179 saveable_obstack = &permanent_obstack;
4182 t = make_node (REFERENCE_TYPE);
4183 TREE_TYPE (t) = to_type;
4185 /* Record this type as the pointer to TO_TYPE. */
4186 TYPE_REFERENCE_TO (to_type) = t;
4190 current_obstack = ambient_obstack;
4191 saveable_obstack = ambient_saveable_obstack;
4195 /* Construct, lay out and return the type of methods belonging to class
4196 BASETYPE and whose arguments and values are described by TYPE.
4197 If that type exists already, reuse it.
4198 TYPE must be a FUNCTION_TYPE node. */
4201 build_method_type (basetype, type)
4202 tree basetype, type;
4207 /* Make a node of the sort we want. */
4208 t = make_node (METHOD_TYPE);
4210 if (TREE_CODE (type) != FUNCTION_TYPE)
4213 TYPE_METHOD_BASETYPE (t) = TYPE_MAIN_VARIANT (basetype);
4214 TREE_TYPE (t) = TREE_TYPE (type);
4216 /* The actual arglist for this function includes a "hidden" argument
4217 which is "this". Put it into the list of argument types. */
4220 = tree_cons (NULL_TREE,
4221 build_pointer_type (basetype), TYPE_ARG_TYPES (type));
4223 /* If we already have such a type, use the old one and free this one. */
4224 hashcode = TYPE_HASH (basetype) + TYPE_HASH (type);
4225 t = type_hash_canon (hashcode, t);
4227 if (TYPE_SIZE (t) == 0)
4233 /* Construct, lay out and return the type of offsets to a value
4234 of type TYPE, within an object of type BASETYPE.
4235 If a suitable offset type exists already, reuse it. */
4238 build_offset_type (basetype, type)
4239 tree basetype, type;
4244 /* Make a node of the sort we want. */
4245 t = make_node (OFFSET_TYPE);
4247 TYPE_OFFSET_BASETYPE (t) = TYPE_MAIN_VARIANT (basetype);
4248 TREE_TYPE (t) = type;
4250 /* If we already have such a type, use the old one and free this one. */
4251 hashcode = TYPE_HASH (basetype) + TYPE_HASH (type);
4252 t = type_hash_canon (hashcode, t);
4254 if (TYPE_SIZE (t) == 0)
4260 /* Create a complex type whose components are COMPONENT_TYPE. */
4263 build_complex_type (component_type)
4264 tree component_type;
4269 /* Make a node of the sort we want. */
4270 t = make_node (COMPLEX_TYPE);
4272 TREE_TYPE (t) = TYPE_MAIN_VARIANT (component_type);
4273 TYPE_VOLATILE (t) = TYPE_VOLATILE (component_type);
4274 TYPE_READONLY (t) = TYPE_READONLY (component_type);
4276 /* If we already have such a type, use the old one and free this one. */
4277 hashcode = TYPE_HASH (component_type);
4278 t = type_hash_canon (hashcode, t);
4280 if (TYPE_SIZE (t) == 0)
4286 /* Return OP, stripped of any conversions to wider types as much as is safe.
4287 Converting the value back to OP's type makes a value equivalent to OP.
4289 If FOR_TYPE is nonzero, we return a value which, if converted to
4290 type FOR_TYPE, would be equivalent to converting OP to type FOR_TYPE.
4292 If FOR_TYPE is nonzero, unaligned bit-field references may be changed to the
4293 narrowest type that can hold the value, even if they don't exactly fit.
4294 Otherwise, bit-field references are changed to a narrower type
4295 only if they can be fetched directly from memory in that type.
4297 OP must have integer, real or enumeral type. Pointers are not allowed!
4299 There are some cases where the obvious value we could return
4300 would regenerate to OP if converted to OP's type,
4301 but would not extend like OP to wider types.
4302 If FOR_TYPE indicates such extension is contemplated, we eschew such values.
4303 For example, if OP is (unsigned short)(signed char)-1,
4304 we avoid returning (signed char)-1 if FOR_TYPE is int,
4305 even though extending that to an unsigned short would regenerate OP,
4306 since the result of extending (signed char)-1 to (int)
4307 is different from (int) OP. */
4310 get_unwidened (op, for_type)
4314 /* Set UNS initially if converting OP to FOR_TYPE is a zero-extension. */
4315 /* TYPE_PRECISION is safe in place of type_precision since
4316 pointer types are not allowed. */
4317 register tree type = TREE_TYPE (op);
4318 register unsigned final_prec
4319 = TYPE_PRECISION (for_type != 0 ? for_type : type);
4321 = (for_type != 0 && for_type != type
4322 && final_prec > TYPE_PRECISION (type)
4323 && TREE_UNSIGNED (type));
4324 register tree win = op;
4326 while (TREE_CODE (op) == NOP_EXPR)
4328 register int bitschange
4329 = TYPE_PRECISION (TREE_TYPE (op))
4330 - TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (op, 0)));
4332 /* Truncations are many-one so cannot be removed.
4333 Unless we are later going to truncate down even farther. */
4335 && final_prec > TYPE_PRECISION (TREE_TYPE (op)))
4338 /* See what's inside this conversion. If we decide to strip it,
4340 op = TREE_OPERAND (op, 0);
4342 /* If we have not stripped any zero-extensions (uns is 0),
4343 we can strip any kind of extension.
4344 If we have previously stripped a zero-extension,
4345 only zero-extensions can safely be stripped.
4346 Any extension can be stripped if the bits it would produce
4347 are all going to be discarded later by truncating to FOR_TYPE. */
4351 if (! uns || final_prec <= TYPE_PRECISION (TREE_TYPE (op)))
4353 /* TREE_UNSIGNED says whether this is a zero-extension.
4354 Let's avoid computing it if it does not affect WIN
4355 and if UNS will not be needed again. */
4356 if ((uns || TREE_CODE (op) == NOP_EXPR)
4357 && TREE_UNSIGNED (TREE_TYPE (op)))
4365 if (TREE_CODE (op) == COMPONENT_REF
4366 /* Since type_for_size always gives an integer type. */
4367 && TREE_CODE (type) != REAL_TYPE
4368 /* Don't crash if field not laid out yet. */
4369 && DECL_SIZE (TREE_OPERAND (op, 1)) != 0)
4371 unsigned innerprec = TREE_INT_CST_LOW (DECL_SIZE (TREE_OPERAND (op, 1)));
4372 type = type_for_size (innerprec, TREE_UNSIGNED (TREE_OPERAND (op, 1)));
4374 /* We can get this structure field in the narrowest type it fits in.
4375 If FOR_TYPE is 0, do this only for a field that matches the
4376 narrower type exactly and is aligned for it
4377 The resulting extension to its nominal type (a fullword type)
4378 must fit the same conditions as for other extensions. */
4380 if (innerprec < TYPE_PRECISION (TREE_TYPE (op))
4381 && (for_type || ! DECL_BIT_FIELD (TREE_OPERAND (op, 1)))
4382 && (! uns || final_prec <= innerprec
4383 || TREE_UNSIGNED (TREE_OPERAND (op, 1)))
4386 win = build (COMPONENT_REF, type, TREE_OPERAND (op, 0),
4387 TREE_OPERAND (op, 1));
4388 TREE_SIDE_EFFECTS (win) = TREE_SIDE_EFFECTS (op);
4389 TREE_THIS_VOLATILE (win) = TREE_THIS_VOLATILE (op);
4390 TREE_RAISES (win) = TREE_RAISES (op);
4396 /* Return OP or a simpler expression for a narrower value
4397 which can be sign-extended or zero-extended to give back OP.
4398 Store in *UNSIGNEDP_PTR either 1 if the value should be zero-extended
4399 or 0 if the value should be sign-extended. */
4402 get_narrower (op, unsignedp_ptr)
4406 register int uns = 0;
4408 register tree win = op;
4410 while (TREE_CODE (op) == NOP_EXPR)
4412 register int bitschange
4413 = TYPE_PRECISION (TREE_TYPE (op))
4414 - TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (op, 0)));
4416 /* Truncations are many-one so cannot be removed. */
4420 /* See what's inside this conversion. If we decide to strip it,
4422 op = TREE_OPERAND (op, 0);
4426 /* An extension: the outermost one can be stripped,
4427 but remember whether it is zero or sign extension. */
4429 uns = TREE_UNSIGNED (TREE_TYPE (op));
4430 /* Otherwise, if a sign extension has been stripped,
4431 only sign extensions can now be stripped;
4432 if a zero extension has been stripped, only zero-extensions. */
4433 else if (uns != TREE_UNSIGNED (TREE_TYPE (op)))
4437 else /* bitschange == 0 */
4439 /* A change in nominal type can always be stripped, but we must
4440 preserve the unsignedness. */
4442 uns = TREE_UNSIGNED (TREE_TYPE (op));
4449 if (TREE_CODE (op) == COMPONENT_REF
4450 /* Since type_for_size always gives an integer type. */
4451 && TREE_CODE (TREE_TYPE (op)) != REAL_TYPE)
4453 unsigned innerprec = TREE_INT_CST_LOW (DECL_SIZE (TREE_OPERAND (op, 1)));
4454 tree type = type_for_size (innerprec, TREE_UNSIGNED (op));
4456 /* We can get this structure field in a narrower type that fits it,
4457 but the resulting extension to its nominal type (a fullword type)
4458 must satisfy the same conditions as for other extensions.
4460 Do this only for fields that are aligned (not bit-fields),
4461 because when bit-field insns will be used there is no
4462 advantage in doing this. */
4464 if (innerprec < TYPE_PRECISION (TREE_TYPE (op))
4465 && ! DECL_BIT_FIELD (TREE_OPERAND (op, 1))
4466 && (first || uns == TREE_UNSIGNED (TREE_OPERAND (op, 1)))
4470 uns = TREE_UNSIGNED (TREE_OPERAND (op, 1));
4471 win = build (COMPONENT_REF, type, TREE_OPERAND (op, 0),
4472 TREE_OPERAND (op, 1));
4473 TREE_SIDE_EFFECTS (win) = TREE_SIDE_EFFECTS (op);
4474 TREE_THIS_VOLATILE (win) = TREE_THIS_VOLATILE (op);
4475 TREE_RAISES (win) = TREE_RAISES (op);
4478 *unsignedp_ptr = uns;
4482 /* Return the precision of a type, for arithmetic purposes.
4483 Supports all types on which arithmetic is possible
4484 (including pointer types).
4485 It's not clear yet what will be right for complex types. */
4488 type_precision (type)
4491 return ((TREE_CODE (type) == INTEGER_TYPE
4492 || TREE_CODE (type) == ENUMERAL_TYPE
4493 || TREE_CODE (type) == REAL_TYPE)
4494 ? TYPE_PRECISION (type) : POINTER_SIZE);
4497 /* Nonzero if integer constant C has a value that is permissible
4498 for type TYPE (an INTEGER_TYPE). */
4501 int_fits_type_p (c, type)
4504 if (TREE_UNSIGNED (type))
4505 return (! (TREE_CODE (TYPE_MAX_VALUE (type)) == INTEGER_CST
4506 && INT_CST_LT_UNSIGNED (TYPE_MAX_VALUE (type), c))
4507 && ! (TREE_CODE (TYPE_MIN_VALUE (type)) == INTEGER_CST
4508 && INT_CST_LT_UNSIGNED (c, TYPE_MIN_VALUE (type)))
4509 /* Negative ints never fit unsigned types. */
4510 && ! (TREE_INT_CST_HIGH (c) < 0
4511 && ! TREE_UNSIGNED (TREE_TYPE (c))));
4513 return (! (TREE_CODE (TYPE_MAX_VALUE (type)) == INTEGER_CST
4514 && INT_CST_LT (TYPE_MAX_VALUE (type), c))
4515 && ! (TREE_CODE (TYPE_MIN_VALUE (type)) == INTEGER_CST
4516 && INT_CST_LT (c, TYPE_MIN_VALUE (type)))
4517 /* Unsigned ints with top bit set never fit signed types. */
4518 && ! (TREE_INT_CST_HIGH (c) < 0
4519 && TREE_UNSIGNED (TREE_TYPE (c))));
4522 /* Return the innermost context enclosing DECL that is
4523 a FUNCTION_DECL, or zero if none. */
4526 decl_function_context (decl)
4531 if (TREE_CODE (decl) == ERROR_MARK)
4534 if (TREE_CODE (decl) == SAVE_EXPR)
4535 context = SAVE_EXPR_CONTEXT (decl);
4537 context = DECL_CONTEXT (decl);
4539 while (context && TREE_CODE (context) != FUNCTION_DECL)
4541 if (TREE_CODE (context) == RECORD_TYPE
4542 || TREE_CODE (context) == UNION_TYPE
4543 || TREE_CODE (context) == QUAL_UNION_TYPE)
4544 context = TYPE_CONTEXT (context);
4545 else if (TREE_CODE (context) == TYPE_DECL)
4546 context = DECL_CONTEXT (context);
4547 else if (TREE_CODE (context) == BLOCK)
4548 context = BLOCK_SUPERCONTEXT (context);
4550 /* Unhandled CONTEXT !? */
4557 /* Return the innermost context enclosing DECL that is
4558 a RECORD_TYPE, UNION_TYPE or QUAL_UNION_TYPE, or zero if none.
4559 TYPE_DECLs and FUNCTION_DECLs are transparent to this function. */
4562 decl_type_context (decl)
4565 tree context = DECL_CONTEXT (decl);
4569 if (TREE_CODE (context) == RECORD_TYPE
4570 || TREE_CODE (context) == UNION_TYPE
4571 || TREE_CODE (context) == QUAL_UNION_TYPE)
4573 if (TREE_CODE (context) == TYPE_DECL
4574 || TREE_CODE (context) == FUNCTION_DECL)
4575 context = DECL_CONTEXT (context);
4576 else if (TREE_CODE (context) == BLOCK)
4577 context = BLOCK_SUPERCONTEXT (context);
4579 /* Unhandled CONTEXT!? */
4585 /* Print debugging information about the size of the
4586 toplev_inline_obstacks. */
4589 print_inline_obstack_statistics ()
4591 struct simple_obstack_stack *current = toplev_inline_obstacks;
4596 for (; current; current = current->next, ++n_obstacks)
4598 struct obstack *o = current->obstack;
4599 struct _obstack_chunk *chunk = o->chunk;
4601 n_alloc += o->next_free - chunk->contents;
4602 chunk = chunk->prev;
4604 for (; chunk; chunk = chunk->prev, ++n_chunks)
4605 n_alloc += chunk->limit - &chunk->contents[0];
4607 fprintf (stderr, "inline obstacks: %d obstacks, %d bytes, %d chunks\n",
4608 n_obstacks, n_alloc, n_chunks);
4611 /* Print debugging information about the obstack O, named STR. */
4614 print_obstack_statistics (str, o)
4618 struct _obstack_chunk *chunk = o->chunk;
4622 n_alloc += o->next_free - chunk->contents;
4623 chunk = chunk->prev;
4627 n_alloc += chunk->limit - &chunk->contents[0];
4628 chunk = chunk->prev;
4630 fprintf (stderr, "obstack %s: %lu bytes, %d chunks\n",
4631 str, n_alloc, n_chunks);
4634 /* Print debugging information about tree nodes generated during the compile,
4635 and any language-specific information. */
4638 dump_tree_statistics ()
4641 int total_nodes, total_bytes;
4643 fprintf (stderr, "\n??? tree nodes created\n\n");
4644 #ifdef GATHER_STATISTICS
4645 fprintf (stderr, "Kind Nodes Bytes\n");
4646 fprintf (stderr, "-------------------------------------\n");
4647 total_nodes = total_bytes = 0;
4648 for (i = 0; i < (int) all_kinds; i++)
4650 fprintf (stderr, "%-20s %6d %9d\n", tree_node_kind_names[i],
4651 tree_node_counts[i], tree_node_sizes[i]);
4652 total_nodes += tree_node_counts[i];
4653 total_bytes += tree_node_sizes[i];
4655 fprintf (stderr, "%-20s %9d\n", "identifier names", id_string_size);
4656 fprintf (stderr, "-------------------------------------\n");
4657 fprintf (stderr, "%-20s %6d %9d\n", "Total", total_nodes, total_bytes);
4658 fprintf (stderr, "-------------------------------------\n");
4660 fprintf (stderr, "(No per-node statistics)\n");
4662 print_obstack_statistics ("permanent_obstack", &permanent_obstack);
4663 print_obstack_statistics ("maybepermanent_obstack", &maybepermanent_obstack);
4664 print_obstack_statistics ("temporary_obstack", &temporary_obstack);
4665 print_obstack_statistics ("momentary_obstack", &momentary_obstack);
4666 print_obstack_statistics ("temp_decl_obstack", &temp_decl_obstack);
4667 print_inline_obstack_statistics ();
4668 print_lang_statistics ();
4671 #define FILE_FUNCTION_PREFIX_LEN 9
4673 #ifndef NO_DOLLAR_IN_LABEL
4674 #define FILE_FUNCTION_FORMAT "_GLOBAL_$D$%s"
4675 #else /* NO_DOLLAR_IN_LABEL */
4676 #ifndef NO_DOT_IN_LABEL
4677 #define FILE_FUNCTION_FORMAT "_GLOBAL_.D.%s"
4678 #else /* NO_DOT_IN_LABEL */
4679 #define FILE_FUNCTION_FORMAT "_GLOBAL__D_%s"
4680 #endif /* NO_DOT_IN_LABEL */
4681 #endif /* NO_DOLLAR_IN_LABEL */
4683 extern char * first_global_object_name;
4685 /* If KIND=='I', return a suitable global initializer (constructor) name.
4686 If KIND=='D', return a suitable global clean-up (destructor) name. */
4689 get_file_function_name (kind)
4695 if (first_global_object_name)
4696 p = first_global_object_name;
4697 else if (main_input_filename)
4698 p = main_input_filename;
4702 buf = (char *) alloca (sizeof (FILE_FUNCTION_FORMAT) + strlen (p));
4704 /* Set up the name of the file-level functions we may need. */
4705 /* Use a global object (which is already required to be unique over
4706 the program) rather than the file name (which imposes extra
4707 constraints). -- Raeburn@MIT.EDU, 10 Jan 1990. */
4708 sprintf (buf, FILE_FUNCTION_FORMAT, p);
4710 /* Don't need to pull weird characters out of global names. */
4711 if (p != first_global_object_name)
4713 for (p = buf+11; *p; p++)
4714 if (! ((*p >= '0' && *p <= '9')
4715 #if 0 /* we always want labels, which are valid C++ identifiers (+ `$') */
4716 #ifndef ASM_IDENTIFY_GCC /* this is required if `.' is invalid -- k. raeburn */
4720 #ifndef NO_DOLLAR_IN_LABEL /* this for `$'; unlikely, but... -- kr */
4723 #ifndef NO_DOT_IN_LABEL /* this for `.'; unlikely, but... */
4726 || (*p >= 'A' && *p <= 'Z')
4727 || (*p >= 'a' && *p <= 'z')))
4731 buf[FILE_FUNCTION_PREFIX_LEN] = kind;
4733 return get_identifier (buf);
4736 /* Expand (the constant part of) a SET_TYPE CONSTRUCTOR node.
4737 The result is placed in BUFFER (which has length BIT_SIZE),
4738 with one bit in each char ('\000' or '\001').
4740 If the constructor is constant, NULL_TREE is returned.
4741 Otherwise, a TREE_LIST of the non-constant elements is emitted. */
4744 get_set_constructor_bits (init, buffer, bit_size)
4751 HOST_WIDE_INT domain_min
4752 = TREE_INT_CST_LOW (TYPE_MIN_VALUE (TYPE_DOMAIN (TREE_TYPE (init))));
4753 tree non_const_bits = NULL_TREE;
4754 for (i = 0; i < bit_size; i++)
4757 for (vals = TREE_OPERAND (init, 1);
4758 vals != NULL_TREE; vals = TREE_CHAIN (vals))
4760 if (TREE_CODE (TREE_VALUE (vals)) != INTEGER_CST
4761 || (TREE_PURPOSE (vals) != NULL_TREE
4762 && TREE_CODE (TREE_PURPOSE (vals)) != INTEGER_CST))
4764 = tree_cons (TREE_PURPOSE (vals), TREE_VALUE (vals), non_const_bits);
4765 else if (TREE_PURPOSE (vals) != NULL_TREE)
4767 /* Set a range of bits to ones. */
4768 HOST_WIDE_INT lo_index
4769 = TREE_INT_CST_LOW (TREE_PURPOSE (vals)) - domain_min;
4770 HOST_WIDE_INT hi_index
4771 = TREE_INT_CST_LOW (TREE_VALUE (vals)) - domain_min;
4772 if (lo_index < 0 || lo_index >= bit_size
4773 || hi_index < 0 || hi_index >= bit_size)
4775 for ( ; lo_index <= hi_index; lo_index++)
4776 buffer[lo_index] = 1;
4780 /* Set a single bit to one. */
4782 = TREE_INT_CST_LOW (TREE_VALUE (vals)) - domain_min;
4783 if (index < 0 || index >= bit_size)
4785 error ("invalid initializer for bit string");
4791 return non_const_bits;
4794 /* Expand (the constant part of) a SET_TYPE CONSTRUCTOR node.
4795 The result is placed in BUFFER (which is an array of bytes).
4796 If the constructor is constant, NULL_TREE is returned.
4797 Otherwise, a TREE_LIST of the non-constant elements is emitted. */
4800 get_set_constructor_bytes (init, buffer, wd_size)
4802 unsigned char *buffer;
4806 tree vals = TREE_OPERAND (init, 1);
4807 int set_word_size = BITS_PER_UNIT;
4808 int bit_size = wd_size * set_word_size;
4810 unsigned char *bytep = buffer;
4811 char *bit_buffer = (char *) alloca(bit_size);
4812 tree non_const_bits = get_set_constructor_bits (init, bit_buffer, bit_size);
4814 for (i = 0; i < wd_size; i++)
4817 for (i = 0; i < bit_size; i++)
4821 if (BYTES_BIG_ENDIAN)
4822 *bytep |= (1 << (set_word_size - 1 - bit_pos));
4824 *bytep |= 1 << bit_pos;
4827 if (bit_pos >= set_word_size)
4828 bit_pos = 0, bytep++;
4830 return non_const_bits;