1 /* Language-independent node constructors for parse phase of GNU compiler.
2 Copyright (C) 1987, 88, 92-97, 1998 Free Software Foundation, Inc.
4 This file is part of GNU CC.
6 GNU CC is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 2, or (at your option)
11 GNU CC is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with GNU CC; see the file COPYING. If not, write to
18 the Free Software Foundation, 59 Temple Place - Suite 330,
19 Boston, MA 02111-1307, USA. */
22 /* This file contains the low level primitives for operating on tree nodes,
23 including allocation, list operations, interning of identifiers,
24 construction of data type nodes and statement nodes,
25 and construction of type conversion nodes. It also contains
26 tables index by tree code that describe how to take apart
29 It is intended to be language-independent, but occasionally
30 calls language-dependent routines defined (for C) in typecheck.c.
32 The low-level allocation routines oballoc and permalloc
33 are used also for allocating many other kinds of objects
34 by all passes of the compiler. */
50 #define obstack_chunk_alloc xmalloc
51 #define obstack_chunk_free free
53 /* Tree nodes of permanent duration are allocated in this obstack.
54 They are the identifier nodes, and everything outside of
55 the bodies and parameters of function definitions. */
57 struct obstack permanent_obstack;
59 /* The initial RTL, and all ..._TYPE nodes, in a function
60 are allocated in this obstack. Usually they are freed at the
61 end of the function, but if the function is inline they are saved.
62 For top-level functions, this is maybepermanent_obstack.
63 Separate obstacks are made for nested functions. */
65 struct obstack *function_maybepermanent_obstack;
67 /* This is the function_maybepermanent_obstack for top-level functions. */
69 struct obstack maybepermanent_obstack;
71 /* This is a list of function_maybepermanent_obstacks for top-level inline
72 functions that are compiled in the middle of compiling other functions. */
74 struct simple_obstack_stack *toplev_inline_obstacks;
76 /* Former elements of toplev_inline_obstacks that have been recycled. */
78 struct simple_obstack_stack *extra_inline_obstacks;
80 /* This is a list of function_maybepermanent_obstacks for inline functions
81 nested in the current function that were compiled in the middle of
82 compiling other functions. */
84 struct simple_obstack_stack *inline_obstacks;
86 /* The contents of the current function definition are allocated
87 in this obstack, and all are freed at the end of the function.
88 For top-level functions, this is temporary_obstack.
89 Separate obstacks are made for nested functions. */
91 struct obstack *function_obstack;
93 /* This is used for reading initializers of global variables. */
95 struct obstack temporary_obstack;
97 /* The tree nodes of an expression are allocated
98 in this obstack, and all are freed at the end of the expression. */
100 struct obstack momentary_obstack;
102 /* The tree nodes of a declarator are allocated
103 in this obstack, and all are freed when the declarator
106 static struct obstack temp_decl_obstack;
108 /* This points at either permanent_obstack
109 or the current function_maybepermanent_obstack. */
111 struct obstack *saveable_obstack;
113 /* This is same as saveable_obstack during parse and expansion phase;
114 it points to the current function's obstack during optimization.
115 This is the obstack to be used for creating rtl objects. */
117 struct obstack *rtl_obstack;
119 /* This points at either permanent_obstack or the current function_obstack. */
121 struct obstack *current_obstack;
123 /* This points at either permanent_obstack or the current function_obstack
124 or momentary_obstack. */
126 struct obstack *expression_obstack;
128 /* Stack of obstack selections for push_obstacks and pop_obstacks. */
132 struct obstack_stack *next;
133 struct obstack *current;
134 struct obstack *saveable;
135 struct obstack *expression;
139 struct obstack_stack *obstack_stack;
141 /* Obstack for allocating struct obstack_stack entries. */
143 static struct obstack obstack_stack_obstack;
145 /* Addresses of first objects in some obstacks.
146 This is for freeing their entire contents. */
147 char *maybepermanent_firstobj;
148 char *temporary_firstobj;
149 char *momentary_firstobj;
150 char *temp_decl_firstobj;
152 /* This is used to preserve objects (mainly array initializers) that need to
153 live until the end of the current function, but no further. */
154 char *momentary_function_firstobj;
156 /* Nonzero means all ..._TYPE nodes should be allocated permanently. */
158 int all_types_permanent;
160 /* Stack of places to restore the momentary obstack back to. */
162 struct momentary_level
164 /* Pointer back to previous such level. */
165 struct momentary_level *prev;
166 /* First object allocated within this level. */
168 /* Value of expression_obstack saved at entry to this level. */
169 struct obstack *obstack;
172 struct momentary_level *momentary_stack;
174 /* Table indexed by tree code giving a string containing a character
175 classifying the tree code. Possibilities are
176 t, d, s, c, r, <, 1, 2 and e. See tree.def for details. */
178 #define DEFTREECODE(SYM, NAME, TYPE, LENGTH) TYPE,
180 char tree_code_type[MAX_TREE_CODES] = {
185 /* Table indexed by tree code giving number of expression
186 operands beyond the fixed part of the node structure.
187 Not used for types or decls. */
189 #define DEFTREECODE(SYM, NAME, TYPE, LENGTH) LENGTH,
191 int tree_code_length[MAX_TREE_CODES] = {
196 /* Names of tree components.
197 Used for printing out the tree and error messages. */
198 #define DEFTREECODE(SYM, NAME, TYPE, LEN) NAME,
200 char *tree_code_name[MAX_TREE_CODES] = {
205 /* Statistics-gathering stuff. */
226 int tree_node_counts[(int)all_kinds];
227 int tree_node_sizes[(int)all_kinds];
228 int id_string_size = 0;
230 char *tree_node_kind_names[] = {
248 /* Hash table for uniquizing IDENTIFIER_NODEs by name. */
250 #define MAX_HASH_TABLE 1009
251 static tree hash_table[MAX_HASH_TABLE]; /* id hash buckets */
253 /* 0 while creating built-in identifiers. */
254 static int do_identifier_warnings;
256 /* Unique id for next decl created. */
257 static int next_decl_uid;
258 /* Unique id for next type created. */
259 static int next_type_uid = 1;
261 /* Here is how primitive or already-canonicalized types' hash
263 #define TYPE_HASH(TYPE) ((unsigned long) (TYPE) & 0777777)
265 extern char *mode_name[];
267 void gcc_obstack_init ();
269 /* Init the principal obstacks. */
274 gcc_obstack_init (&obstack_stack_obstack);
275 gcc_obstack_init (&permanent_obstack);
277 gcc_obstack_init (&temporary_obstack);
278 temporary_firstobj = (char *) obstack_alloc (&temporary_obstack, 0);
279 gcc_obstack_init (&momentary_obstack);
280 momentary_firstobj = (char *) obstack_alloc (&momentary_obstack, 0);
281 momentary_function_firstobj = momentary_firstobj;
282 gcc_obstack_init (&maybepermanent_obstack);
283 maybepermanent_firstobj
284 = (char *) obstack_alloc (&maybepermanent_obstack, 0);
285 gcc_obstack_init (&temp_decl_obstack);
286 temp_decl_firstobj = (char *) obstack_alloc (&temp_decl_obstack, 0);
288 function_obstack = &temporary_obstack;
289 function_maybepermanent_obstack = &maybepermanent_obstack;
290 current_obstack = &permanent_obstack;
291 expression_obstack = &permanent_obstack;
292 rtl_obstack = saveable_obstack = &permanent_obstack;
294 /* Init the hash table of identifiers. */
295 bzero ((char *) hash_table, sizeof hash_table);
299 gcc_obstack_init (obstack)
300 struct obstack *obstack;
302 /* Let particular systems override the size of a chunk. */
303 #ifndef OBSTACK_CHUNK_SIZE
304 #define OBSTACK_CHUNK_SIZE 0
306 /* Let them override the alloc and free routines too. */
307 #ifndef OBSTACK_CHUNK_ALLOC
308 #define OBSTACK_CHUNK_ALLOC xmalloc
310 #ifndef OBSTACK_CHUNK_FREE
311 #define OBSTACK_CHUNK_FREE free
313 _obstack_begin (obstack, OBSTACK_CHUNK_SIZE, 0,
314 (void *(*) ()) OBSTACK_CHUNK_ALLOC,
315 (void (*) ()) OBSTACK_CHUNK_FREE);
318 /* Save all variables describing the current status into the structure *P.
319 This is used before starting a nested function.
321 CONTEXT is the decl_function_context for the function we're about to
322 compile; if it isn't current_function_decl, we have to play some games. */
325 save_tree_status (p, context)
329 p->all_types_permanent = all_types_permanent;
330 p->momentary_stack = momentary_stack;
331 p->maybepermanent_firstobj = maybepermanent_firstobj;
332 p->temporary_firstobj = temporary_firstobj;
333 p->momentary_firstobj = momentary_firstobj;
334 p->momentary_function_firstobj = momentary_function_firstobj;
335 p->function_obstack = function_obstack;
336 p->function_maybepermanent_obstack = function_maybepermanent_obstack;
337 p->current_obstack = current_obstack;
338 p->expression_obstack = expression_obstack;
339 p->saveable_obstack = saveable_obstack;
340 p->rtl_obstack = rtl_obstack;
341 p->inline_obstacks = inline_obstacks;
343 if (context == current_function_decl)
344 /* Objects that need to be saved in this function can be in the nonsaved
345 obstack of the enclosing function since they can't possibly be needed
346 once it has returned. */
347 function_maybepermanent_obstack = function_obstack;
350 /* We're compiling a function which isn't nested in the current
351 function. We need to create a new maybepermanent_obstack for this
352 function, since it can't go onto any of the existing obstacks. */
353 struct simple_obstack_stack **head;
354 struct simple_obstack_stack *current;
356 if (context == NULL_TREE)
357 head = &toplev_inline_obstacks;
360 struct function *f = find_function_data (context);
361 head = &f->inline_obstacks;
364 if (context == NULL_TREE && extra_inline_obstacks)
366 current = extra_inline_obstacks;
367 extra_inline_obstacks = current->next;
371 current = ((struct simple_obstack_stack *)
372 xmalloc (sizeof (struct simple_obstack_stack)));
375 = (struct obstack *) xmalloc (sizeof (struct obstack));
376 gcc_obstack_init (current->obstack);
379 function_maybepermanent_obstack = current->obstack;
381 current->next = *head;
385 maybepermanent_firstobj
386 = (char *) obstack_finish (function_maybepermanent_obstack);
388 function_obstack = (struct obstack *) xmalloc (sizeof (struct obstack));
389 gcc_obstack_init (function_obstack);
391 current_obstack = &permanent_obstack;
392 expression_obstack = &permanent_obstack;
393 rtl_obstack = saveable_obstack = &permanent_obstack;
395 temporary_firstobj = (char *) obstack_alloc (&temporary_obstack, 0);
396 momentary_firstobj = (char *) obstack_finish (&momentary_obstack);
397 momentary_function_firstobj = momentary_firstobj;
400 /* Restore all variables describing the current status from the structure *P.
401 This is used after a nested function. */
404 restore_tree_status (p, context)
408 all_types_permanent = p->all_types_permanent;
409 momentary_stack = p->momentary_stack;
411 obstack_free (&momentary_obstack, momentary_function_firstobj);
413 /* Free saveable storage used by the function just compiled and not
416 CAUTION: This is in function_obstack of the containing function.
417 So we must be sure that we never allocate from that obstack during
418 the compilation of a nested function if we expect it to survive
419 past the nested function's end. */
420 obstack_free (function_maybepermanent_obstack, maybepermanent_firstobj);
422 /* If we were compiling a toplevel function, we can free this space now. */
423 if (context == NULL_TREE)
425 obstack_free (&temporary_obstack, temporary_firstobj);
426 obstack_free (&momentary_obstack, momentary_function_firstobj);
429 /* If we were compiling a toplevel function that we don't actually want
430 to save anything from, return the obstack to the pool. */
431 if (context == NULL_TREE
432 && obstack_empty_p (function_maybepermanent_obstack))
434 struct simple_obstack_stack *current, **p = &toplev_inline_obstacks;
438 while ((*p)->obstack != function_maybepermanent_obstack)
443 current->next = extra_inline_obstacks;
444 extra_inline_obstacks = current;
448 obstack_free (function_obstack, 0);
449 free (function_obstack);
451 temporary_firstobj = p->temporary_firstobj;
452 momentary_firstobj = p->momentary_firstobj;
453 momentary_function_firstobj = p->momentary_function_firstobj;
454 maybepermanent_firstobj = p->maybepermanent_firstobj;
455 function_obstack = p->function_obstack;
456 function_maybepermanent_obstack = p->function_maybepermanent_obstack;
457 current_obstack = p->current_obstack;
458 expression_obstack = p->expression_obstack;
459 saveable_obstack = p->saveable_obstack;
460 rtl_obstack = p->rtl_obstack;
461 inline_obstacks = p->inline_obstacks;
464 /* Start allocating on the temporary (per function) obstack.
465 This is done in start_function before parsing the function body,
466 and before each initialization at top level, and to go back
467 to temporary allocation after doing permanent_allocation. */
470 temporary_allocation ()
472 /* Note that function_obstack at top level points to temporary_obstack.
473 But within a nested function context, it is a separate obstack. */
474 current_obstack = function_obstack;
475 expression_obstack = function_obstack;
476 rtl_obstack = saveable_obstack = function_maybepermanent_obstack;
481 /* Start allocating on the permanent obstack but don't
482 free the temporary data. After calling this, call
483 `permanent_allocation' to fully resume permanent allocation status. */
486 end_temporary_allocation ()
488 current_obstack = &permanent_obstack;
489 expression_obstack = &permanent_obstack;
490 rtl_obstack = saveable_obstack = &permanent_obstack;
493 /* Resume allocating on the temporary obstack, undoing
494 effects of `end_temporary_allocation'. */
497 resume_temporary_allocation ()
499 current_obstack = function_obstack;
500 expression_obstack = function_obstack;
501 rtl_obstack = saveable_obstack = function_maybepermanent_obstack;
504 /* While doing temporary allocation, switch to allocating in such a
505 way as to save all nodes if the function is inlined. Call
506 resume_temporary_allocation to go back to ordinary temporary
510 saveable_allocation ()
512 /* Note that function_obstack at top level points to temporary_obstack.
513 But within a nested function context, it is a separate obstack. */
514 expression_obstack = current_obstack = saveable_obstack;
517 /* Switch to current obstack CURRENT and maybepermanent obstack SAVEABLE,
518 recording the previously current obstacks on a stack.
519 This does not free any storage in any obstack. */
522 push_obstacks (current, saveable)
523 struct obstack *current, *saveable;
525 struct obstack_stack *p
526 = (struct obstack_stack *) obstack_alloc (&obstack_stack_obstack,
527 (sizeof (struct obstack_stack)));
529 p->current = current_obstack;
530 p->saveable = saveable_obstack;
531 p->expression = expression_obstack;
532 p->rtl = rtl_obstack;
533 p->next = obstack_stack;
536 current_obstack = current;
537 expression_obstack = current;
538 rtl_obstack = saveable_obstack = saveable;
541 /* Save the current set of obstacks, but don't change them. */
544 push_obstacks_nochange ()
546 struct obstack_stack *p
547 = (struct obstack_stack *) obstack_alloc (&obstack_stack_obstack,
548 (sizeof (struct obstack_stack)));
550 p->current = current_obstack;
551 p->saveable = saveable_obstack;
552 p->expression = expression_obstack;
553 p->rtl = rtl_obstack;
554 p->next = obstack_stack;
558 /* Pop the obstack selection stack. */
563 struct obstack_stack *p = obstack_stack;
564 obstack_stack = p->next;
566 current_obstack = p->current;
567 saveable_obstack = p->saveable;
568 expression_obstack = p->expression;
569 rtl_obstack = p->rtl;
571 obstack_free (&obstack_stack_obstack, p);
574 /* Nonzero if temporary allocation is currently in effect.
575 Zero if currently doing permanent allocation. */
578 allocation_temporary_p ()
580 return current_obstack != &permanent_obstack;
583 /* Go back to allocating on the permanent obstack
584 and free everything in the temporary obstack.
586 FUNCTION_END is true only if we have just finished compiling a function.
587 In that case, we also free preserved initial values on the momentary
591 permanent_allocation (function_end)
594 /* Free up previous temporary obstack data */
595 obstack_free (&temporary_obstack, temporary_firstobj);
598 obstack_free (&momentary_obstack, momentary_function_firstobj);
599 momentary_firstobj = momentary_function_firstobj;
602 obstack_free (&momentary_obstack, momentary_firstobj);
603 obstack_free (function_maybepermanent_obstack, maybepermanent_firstobj);
604 obstack_free (&temp_decl_obstack, temp_decl_firstobj);
606 /* Free up the maybepermanent_obstacks for any of our nested functions
607 which were compiled at a lower level. */
608 while (inline_obstacks)
610 struct simple_obstack_stack *current = inline_obstacks;
611 inline_obstacks = current->next;
612 obstack_free (current->obstack, 0);
613 free (current->obstack);
617 current_obstack = &permanent_obstack;
618 expression_obstack = &permanent_obstack;
619 rtl_obstack = saveable_obstack = &permanent_obstack;
622 /* Save permanently everything on the maybepermanent_obstack. */
627 maybepermanent_firstobj
628 = (char *) obstack_alloc (function_maybepermanent_obstack, 0);
632 preserve_initializer ()
634 struct momentary_level *tem;
638 = (char *) obstack_alloc (&temporary_obstack, 0);
639 maybepermanent_firstobj
640 = (char *) obstack_alloc (function_maybepermanent_obstack, 0);
642 old_momentary = momentary_firstobj;
644 = (char *) obstack_alloc (&momentary_obstack, 0);
645 if (momentary_firstobj != old_momentary)
646 for (tem = momentary_stack; tem; tem = tem->prev)
647 tem->base = momentary_firstobj;
650 /* Start allocating new rtl in current_obstack.
651 Use resume_temporary_allocation
652 to go back to allocating rtl in saveable_obstack. */
655 rtl_in_current_obstack ()
657 rtl_obstack = current_obstack;
660 /* Start allocating rtl from saveable_obstack. Intended to be used after
661 a call to push_obstacks_nochange. */
664 rtl_in_saveable_obstack ()
666 rtl_obstack = saveable_obstack;
669 /* Allocate SIZE bytes in the current obstack
670 and return a pointer to them.
671 In practice the current obstack is always the temporary one. */
677 return (char *) obstack_alloc (current_obstack, size);
680 /* Free the object PTR in the current obstack
681 as well as everything allocated since PTR.
682 In practice the current obstack is always the temporary one. */
688 obstack_free (current_obstack, ptr);
691 /* Allocate SIZE bytes in the permanent obstack
692 and return a pointer to them. */
698 return (char *) obstack_alloc (&permanent_obstack, size);
701 /* Allocate NELEM items of SIZE bytes in the permanent obstack
702 and return a pointer to them. The storage is cleared before
703 returning the value. */
706 perm_calloc (nelem, size)
710 char *rval = (char *) obstack_alloc (&permanent_obstack, nelem * size);
711 bzero (rval, nelem * size);
715 /* Allocate SIZE bytes in the saveable obstack
716 and return a pointer to them. */
722 return (char *) obstack_alloc (saveable_obstack, size);
725 /* Allocate SIZE bytes in the expression obstack
726 and return a pointer to them. */
732 return (char *) obstack_alloc (expression_obstack, size);
735 /* Print out which obstack an object is in. */
738 print_obstack_name (object, file, prefix)
743 struct obstack *obstack = NULL;
744 char *obstack_name = NULL;
747 for (p = outer_function_chain; p; p = p->next)
749 if (_obstack_allocated_p (p->function_obstack, object))
751 obstack = p->function_obstack;
752 obstack_name = "containing function obstack";
754 if (_obstack_allocated_p (p->function_maybepermanent_obstack, object))
756 obstack = p->function_maybepermanent_obstack;
757 obstack_name = "containing function maybepermanent obstack";
761 if (_obstack_allocated_p (&obstack_stack_obstack, object))
763 obstack = &obstack_stack_obstack;
764 obstack_name = "obstack_stack_obstack";
766 else if (_obstack_allocated_p (function_obstack, object))
768 obstack = function_obstack;
769 obstack_name = "function obstack";
771 else if (_obstack_allocated_p (&permanent_obstack, object))
773 obstack = &permanent_obstack;
774 obstack_name = "permanent_obstack";
776 else if (_obstack_allocated_p (&momentary_obstack, object))
778 obstack = &momentary_obstack;
779 obstack_name = "momentary_obstack";
781 else if (_obstack_allocated_p (function_maybepermanent_obstack, object))
783 obstack = function_maybepermanent_obstack;
784 obstack_name = "function maybepermanent obstack";
786 else if (_obstack_allocated_p (&temp_decl_obstack, object))
788 obstack = &temp_decl_obstack;
789 obstack_name = "temp_decl_obstack";
792 /* Check to see if the object is in the free area of the obstack. */
795 if (object >= obstack->next_free
796 && object < obstack->chunk_limit)
797 fprintf (file, "%s in free portion of obstack %s",
798 prefix, obstack_name);
800 fprintf (file, "%s allocated from %s", prefix, obstack_name);
803 fprintf (file, "%s not allocated from any obstack", prefix);
807 debug_obstack (object)
810 print_obstack_name (object, stderr, "object");
811 fprintf (stderr, ".\n");
814 /* Return 1 if OBJ is in the permanent obstack.
815 This is slow, and should be used only for debugging.
816 Use TREE_PERMANENT for other purposes. */
819 object_permanent_p (obj)
822 return _obstack_allocated_p (&permanent_obstack, obj);
825 /* Start a level of momentary allocation.
826 In C, each compound statement has its own level
827 and that level is freed at the end of each statement.
828 All expression nodes are allocated in the momentary allocation level. */
833 struct momentary_level *tem
834 = (struct momentary_level *) obstack_alloc (&momentary_obstack,
835 sizeof (struct momentary_level));
836 tem->prev = momentary_stack;
837 tem->base = (char *) obstack_base (&momentary_obstack);
838 tem->obstack = expression_obstack;
839 momentary_stack = tem;
840 expression_obstack = &momentary_obstack;
843 /* Set things up so the next clear_momentary will only clear memory
844 past our present position in momentary_obstack. */
847 preserve_momentary ()
849 momentary_stack->base = (char *) obstack_base (&momentary_obstack);
852 /* Free all the storage in the current momentary-allocation level.
853 In C, this happens at the end of each statement. */
858 obstack_free (&momentary_obstack, momentary_stack->base);
861 /* Discard a level of momentary allocation.
862 In C, this happens at the end of each compound statement.
863 Restore the status of expression node allocation
864 that was in effect before this level was created. */
869 struct momentary_level *tem = momentary_stack;
870 momentary_stack = tem->prev;
871 expression_obstack = tem->obstack;
872 /* We can't free TEM from the momentary_obstack, because there might
873 be objects above it which have been saved. We can free back to the
874 stack of the level we are popping off though. */
875 obstack_free (&momentary_obstack, tem->base);
878 /* Pop back to the previous level of momentary allocation,
879 but don't free any momentary data just yet. */
882 pop_momentary_nofree ()
884 struct momentary_level *tem = momentary_stack;
885 momentary_stack = tem->prev;
886 expression_obstack = tem->obstack;
889 /* Call when starting to parse a declaration:
890 make expressions in the declaration last the length of the function.
891 Returns an argument that should be passed to resume_momentary later. */
896 register int tem = expression_obstack == &momentary_obstack;
897 expression_obstack = saveable_obstack;
901 /* Call when finished parsing a declaration:
902 restore the treatment of node-allocation that was
903 in effect before the suspension.
904 YES should be the value previously returned by suspend_momentary. */
907 resume_momentary (yes)
911 expression_obstack = &momentary_obstack;
914 /* Init the tables indexed by tree code.
915 Note that languages can add to these tables to define their own codes. */
923 /* Return a newly allocated node of code CODE.
924 Initialize the node's unique id and its TREE_PERMANENT flag.
925 For decl and type nodes, some other fields are initialized.
926 The rest of the node is initialized to zero.
928 Achoo! I got a code in the node. */
935 register int type = TREE_CODE_CLASS (code);
937 register struct obstack *obstack = current_obstack;
939 #ifdef GATHER_STATISTICS
940 register tree_node_kind kind;
945 case 'd': /* A decl node */
946 #ifdef GATHER_STATISTICS
949 length = sizeof (struct tree_decl);
950 /* All decls in an inline function need to be saved. */
951 if (obstack != &permanent_obstack)
952 obstack = saveable_obstack;
954 /* PARM_DECLs go on the context of the parent. If this is a nested
955 function, then we must allocate the PARM_DECL on the parent's
956 obstack, so that they will live to the end of the parent's
957 closing brace. This is necessary in case we try to inline the
958 function into its parent.
960 PARM_DECLs of top-level functions do not have this problem. However,
961 we allocate them where we put the FUNCTION_DECL for languages such as
962 Ada that need to consult some flags in the PARM_DECLs of the function
965 See comment in restore_tree_status for why we can't put this
966 in function_obstack. */
967 if (code == PARM_DECL && obstack != &permanent_obstack)
970 if (current_function_decl)
971 context = decl_function_context (current_function_decl);
975 = find_function_data (context)->function_maybepermanent_obstack;
979 case 't': /* a type node */
980 #ifdef GATHER_STATISTICS
983 length = sizeof (struct tree_type);
984 /* All data types are put where we can preserve them if nec. */
985 if (obstack != &permanent_obstack)
986 obstack = all_types_permanent ? &permanent_obstack : saveable_obstack;
989 case 'b': /* a lexical block */
990 #ifdef GATHER_STATISTICS
993 length = sizeof (struct tree_block);
994 /* All BLOCK nodes are put where we can preserve them if nec. */
995 if (obstack != &permanent_obstack)
996 obstack = saveable_obstack;
999 case 's': /* an expression with side effects */
1000 #ifdef GATHER_STATISTICS
1004 case 'r': /* a reference */
1005 #ifdef GATHER_STATISTICS
1009 case 'e': /* an expression */
1010 case '<': /* a comparison expression */
1011 case '1': /* a unary arithmetic expression */
1012 case '2': /* a binary arithmetic expression */
1013 #ifdef GATHER_STATISTICS
1017 obstack = expression_obstack;
1018 /* All BIND_EXPR nodes are put where we can preserve them if nec. */
1019 if (code == BIND_EXPR && obstack != &permanent_obstack)
1020 obstack = saveable_obstack;
1021 length = sizeof (struct tree_exp)
1022 + (tree_code_length[(int) code] - 1) * sizeof (char *);
1025 case 'c': /* a constant */
1026 #ifdef GATHER_STATISTICS
1029 obstack = expression_obstack;
1031 /* We can't use tree_code_length for INTEGER_CST, since the number of
1032 words is machine-dependent due to varying length of HOST_WIDE_INT,
1033 which might be wider than a pointer (e.g., long long). Similarly
1034 for REAL_CST, since the number of words is machine-dependent due
1035 to varying size and alignment of `double'. */
1037 if (code == INTEGER_CST)
1038 length = sizeof (struct tree_int_cst);
1039 else if (code == REAL_CST)
1040 length = sizeof (struct tree_real_cst);
1042 length = sizeof (struct tree_common)
1043 + tree_code_length[(int) code] * sizeof (char *);
1046 case 'x': /* something random, like an identifier. */
1047 #ifdef GATHER_STATISTICS
1048 if (code == IDENTIFIER_NODE)
1050 else if (code == OP_IDENTIFIER)
1052 else if (code == TREE_VEC)
1057 length = sizeof (struct tree_common)
1058 + tree_code_length[(int) code] * sizeof (char *);
1059 /* Identifier nodes are always permanent since they are
1060 unique in a compiler run. */
1061 if (code == IDENTIFIER_NODE) obstack = &permanent_obstack;
1068 t = (tree) obstack_alloc (obstack, length);
1070 #ifdef GATHER_STATISTICS
1071 tree_node_counts[(int)kind]++;
1072 tree_node_sizes[(int)kind] += length;
1075 /* Clear a word at a time. */
1076 for (i = (length / sizeof (int)) - 1; i >= 0; i--)
1078 /* Clear any extra bytes. */
1079 for (i = length / sizeof (int) * sizeof (int); i < length; i++)
1080 ((char *) t)[i] = 0;
1082 TREE_SET_CODE (t, code);
1083 if (obstack == &permanent_obstack)
1084 TREE_PERMANENT (t) = 1;
1089 TREE_SIDE_EFFECTS (t) = 1;
1090 TREE_TYPE (t) = void_type_node;
1094 if (code != FUNCTION_DECL)
1096 DECL_IN_SYSTEM_HEADER (t)
1097 = in_system_header && (obstack == &permanent_obstack);
1098 DECL_SOURCE_LINE (t) = lineno;
1099 DECL_SOURCE_FILE (t) = (input_filename) ? input_filename : "<built-in>";
1100 DECL_UID (t) = next_decl_uid++;
1104 TYPE_UID (t) = next_type_uid++;
1106 TYPE_MAIN_VARIANT (t) = t;
1107 TYPE_OBSTACK (t) = obstack;
1108 TYPE_ATTRIBUTES (t) = NULL_TREE;
1109 #ifdef SET_DEFAULT_TYPE_ATTRIBUTES
1110 SET_DEFAULT_TYPE_ATTRIBUTES (t);
1115 TREE_CONSTANT (t) = 1;
1122 /* Return a new node with the same contents as NODE
1123 except that its TREE_CHAIN is zero and it has a fresh uid. */
1130 register enum tree_code code = TREE_CODE (node);
1131 register int length = 0;
1134 switch (TREE_CODE_CLASS (code))
1136 case 'd': /* A decl node */
1137 length = sizeof (struct tree_decl);
1140 case 't': /* a type node */
1141 length = sizeof (struct tree_type);
1144 case 'b': /* a lexical block node */
1145 length = sizeof (struct tree_block);
1148 case 'r': /* a reference */
1149 case 'e': /* an expression */
1150 case 's': /* an expression with side effects */
1151 case '<': /* a comparison expression */
1152 case '1': /* a unary arithmetic expression */
1153 case '2': /* a binary arithmetic expression */
1154 length = sizeof (struct tree_exp)
1155 + (tree_code_length[(int) code] - 1) * sizeof (char *);
1158 case 'c': /* a constant */
1159 /* We can't use tree_code_length for INTEGER_CST, since the number of
1160 words is machine-dependent due to varying length of HOST_WIDE_INT,
1161 which might be wider than a pointer (e.g., long long). Similarly
1162 for REAL_CST, since the number of words is machine-dependent due
1163 to varying size and alignment of `double'. */
1164 if (code == INTEGER_CST)
1165 length = sizeof (struct tree_int_cst);
1166 else if (code == REAL_CST)
1167 length = sizeof (struct tree_real_cst);
1169 length = (sizeof (struct tree_common)
1170 + tree_code_length[(int) code] * sizeof (char *));
1173 case 'x': /* something random, like an identifier. */
1174 length = sizeof (struct tree_common)
1175 + tree_code_length[(int) code] * sizeof (char *);
1176 if (code == TREE_VEC)
1177 length += (TREE_VEC_LENGTH (node) - 1) * sizeof (char *);
1180 t = (tree) obstack_alloc (current_obstack, length);
1182 for (i = (length / sizeof (int)) - 1; i >= 0; i--)
1183 ((int *) t)[i] = ((int *) node)[i];
1184 /* Clear any extra bytes. */
1185 for (i = length / sizeof (int) * sizeof (int); i < length; i++)
1186 ((char *) t)[i] = ((char *) node)[i];
1189 TREE_ASM_WRITTEN (t) = 0;
1191 if (TREE_CODE_CLASS (code) == 'd')
1192 DECL_UID (t) = next_decl_uid++;
1193 else if (TREE_CODE_CLASS (code) == 't')
1195 TYPE_UID (t) = next_type_uid++;
1196 TYPE_OBSTACK (t) = current_obstack;
1198 /* The following is so that the debug code for
1199 the copy is different from the original type.
1200 The two statements usually duplicate each other
1201 (because they clear fields of the same union),
1202 but the optimizer should catch that. */
1203 TYPE_SYMTAB_POINTER (t) = 0;
1204 TYPE_SYMTAB_ADDRESS (t) = 0;
1207 TREE_PERMANENT (t) = (current_obstack == &permanent_obstack);
1212 /* Return a copy of a chain of nodes, chained through the TREE_CHAIN field.
1213 For example, this can copy a list made of TREE_LIST nodes. */
1220 register tree prev, next;
1225 head = prev = copy_node (list);
1226 next = TREE_CHAIN (list);
1229 TREE_CHAIN (prev) = copy_node (next);
1230 prev = TREE_CHAIN (prev);
1231 next = TREE_CHAIN (next);
1238 /* Return an IDENTIFIER_NODE whose name is TEXT (a null-terminated string).
1239 If an identifier with that name has previously been referred to,
1240 the same node is returned this time. */
1243 get_identifier (text)
1244 register char *text;
1249 register int len, hash_len;
1251 /* Compute length of text in len. */
1252 for (len = 0; text[len]; len++);
1254 /* Decide how much of that length to hash on */
1256 if (warn_id_clash && len > id_clash_len)
1257 hash_len = id_clash_len;
1259 /* Compute hash code */
1260 hi = hash_len * 613 + (unsigned) text[0];
1261 for (i = 1; i < hash_len; i += 2)
1262 hi = ((hi * 613) + (unsigned) (text[i]));
1264 hi &= (1 << HASHBITS) - 1;
1265 hi %= MAX_HASH_TABLE;
1267 /* Search table for identifier */
1268 for (idp = hash_table[hi]; idp; idp = TREE_CHAIN (idp))
1269 if (IDENTIFIER_LENGTH (idp) == len
1270 && IDENTIFIER_POINTER (idp)[0] == text[0]
1271 && !bcmp (IDENTIFIER_POINTER (idp), text, len))
1272 return idp; /* <-- return if found */
1274 /* Not found; optionally warn about a similar identifier */
1275 if (warn_id_clash && do_identifier_warnings && len >= id_clash_len)
1276 for (idp = hash_table[hi]; idp; idp = TREE_CHAIN (idp))
1277 if (!strncmp (IDENTIFIER_POINTER (idp), text, id_clash_len))
1279 warning ("`%s' and `%s' identical in first %d characters",
1280 IDENTIFIER_POINTER (idp), text, id_clash_len);
1284 if (tree_code_length[(int) IDENTIFIER_NODE] < 0)
1285 abort (); /* set_identifier_size hasn't been called. */
1287 /* Not found, create one, add to chain */
1288 idp = make_node (IDENTIFIER_NODE);
1289 IDENTIFIER_LENGTH (idp) = len;
1290 #ifdef GATHER_STATISTICS
1291 id_string_size += len;
1294 IDENTIFIER_POINTER (idp) = obstack_copy0 (&permanent_obstack, text, len);
1296 TREE_CHAIN (idp) = hash_table[hi];
1297 hash_table[hi] = idp;
1298 return idp; /* <-- return if created */
1301 /* If an identifier with the name TEXT (a null-terminated string) has
1302 previously been referred to, return that node; otherwise return
1306 maybe_get_identifier (text)
1307 register char *text;
1312 register int len, hash_len;
1314 /* Compute length of text in len. */
1315 for (len = 0; text[len]; len++);
1317 /* Decide how much of that length to hash on */
1319 if (warn_id_clash && len > id_clash_len)
1320 hash_len = id_clash_len;
1322 /* Compute hash code */
1323 hi = hash_len * 613 + (unsigned) text[0];
1324 for (i = 1; i < hash_len; i += 2)
1325 hi = ((hi * 613) + (unsigned) (text[i]));
1327 hi &= (1 << HASHBITS) - 1;
1328 hi %= MAX_HASH_TABLE;
1330 /* Search table for identifier */
1331 for (idp = hash_table[hi]; idp; idp = TREE_CHAIN (idp))
1332 if (IDENTIFIER_LENGTH (idp) == len
1333 && IDENTIFIER_POINTER (idp)[0] == text[0]
1334 && !bcmp (IDENTIFIER_POINTER (idp), text, len))
1335 return idp; /* <-- return if found */
1340 /* Enable warnings on similar identifiers (if requested).
1341 Done after the built-in identifiers are created. */
1344 start_identifier_warnings ()
1346 do_identifier_warnings = 1;
1349 /* Record the size of an identifier node for the language in use.
1350 SIZE is the total size in bytes.
1351 This is called by the language-specific files. This must be
1352 called before allocating any identifiers. */
1355 set_identifier_size (size)
1358 tree_code_length[(int) IDENTIFIER_NODE]
1359 = (size - sizeof (struct tree_common)) / sizeof (tree);
1362 /* Return a newly constructed INTEGER_CST node whose constant value
1363 is specified by the two ints LOW and HI.
1364 The TREE_TYPE is set to `int'.
1366 This function should be used via the `build_int_2' macro. */
1369 build_int_2_wide (low, hi)
1370 HOST_WIDE_INT low, hi;
1372 register tree t = make_node (INTEGER_CST);
1373 TREE_INT_CST_LOW (t) = low;
1374 TREE_INT_CST_HIGH (t) = hi;
1375 TREE_TYPE (t) = integer_type_node;
1379 /* Return a new REAL_CST node whose type is TYPE and value is D. */
1382 build_real (type, d)
1389 /* Check for valid float value for this type on this target machine;
1390 if not, can print error message and store a valid value in D. */
1391 #ifdef CHECK_FLOAT_VALUE
1392 CHECK_FLOAT_VALUE (TYPE_MODE (type), d, overflow);
1395 v = make_node (REAL_CST);
1396 TREE_TYPE (v) = type;
1397 TREE_REAL_CST (v) = d;
1398 TREE_OVERFLOW (v) = TREE_CONSTANT_OVERFLOW (v) = overflow;
1402 /* Return a new REAL_CST node whose type is TYPE
1403 and whose value is the integer value of the INTEGER_CST node I. */
1405 #if !defined (REAL_IS_NOT_DOUBLE) || defined (REAL_ARITHMETIC)
1408 real_value_from_int_cst (type, i)
1413 #ifdef REAL_ARITHMETIC
1414 if (! TREE_UNSIGNED (TREE_TYPE (i)))
1415 REAL_VALUE_FROM_INT (d, TREE_INT_CST_LOW (i), TREE_INT_CST_HIGH (i),
1418 REAL_VALUE_FROM_UNSIGNED_INT (d, TREE_INT_CST_LOW (i),
1419 TREE_INT_CST_HIGH (i), TYPE_MODE (type));
1420 #else /* not REAL_ARITHMETIC */
1421 /* Some 386 compilers mishandle unsigned int to float conversions,
1422 so introduce a temporary variable E to avoid those bugs. */
1423 if (TREE_INT_CST_HIGH (i) < 0 && ! TREE_UNSIGNED (TREE_TYPE (i)))
1427 d = (double) (~ TREE_INT_CST_HIGH (i));
1428 e = ((double) ((HOST_WIDE_INT) 1 << (HOST_BITS_PER_WIDE_INT / 2))
1429 * (double) ((HOST_WIDE_INT) 1 << (HOST_BITS_PER_WIDE_INT / 2)));
1431 e = (double) (unsigned HOST_WIDE_INT) (~ TREE_INT_CST_LOW (i));
1439 d = (double) (unsigned HOST_WIDE_INT) TREE_INT_CST_HIGH (i);
1440 e = ((double) ((HOST_WIDE_INT) 1 << (HOST_BITS_PER_WIDE_INT / 2))
1441 * (double) ((HOST_WIDE_INT) 1 << (HOST_BITS_PER_WIDE_INT / 2)));
1443 e = (double) (unsigned HOST_WIDE_INT) TREE_INT_CST_LOW (i);
1446 #endif /* not REAL_ARITHMETIC */
1450 /* This function can't be implemented if we can't do arithmetic
1451 on the float representation. */
1454 build_real_from_int_cst (type, i)
1459 int overflow = TREE_OVERFLOW (i);
1461 jmp_buf float_error;
1463 v = make_node (REAL_CST);
1464 TREE_TYPE (v) = type;
1466 if (setjmp (float_error))
1473 set_float_handler (float_error);
1475 #ifdef REAL_ARITHMETIC
1476 d = real_value_from_int_cst (type, i);
1478 d = REAL_VALUE_TRUNCATE (TYPE_MODE (type),
1479 real_value_from_int_cst (type, i));
1482 /* Check for valid float value for this type on this target machine. */
1485 set_float_handler (NULL_PTR);
1487 #ifdef CHECK_FLOAT_VALUE
1488 CHECK_FLOAT_VALUE (TYPE_MODE (type), d, overflow);
1491 TREE_REAL_CST (v) = d;
1492 TREE_OVERFLOW (v) = TREE_CONSTANT_OVERFLOW (v) = overflow;
1496 #endif /* not REAL_IS_NOT_DOUBLE, or REAL_ARITHMETIC */
1498 /* Return a newly constructed STRING_CST node whose value is
1499 the LEN characters at STR.
1500 The TREE_TYPE is not initialized. */
1503 build_string (len, str)
1507 /* Put the string in saveable_obstack since it will be placed in the RTL
1508 for an "asm" statement and will also be kept around a while if
1509 deferring constant output in varasm.c. */
1511 register tree s = make_node (STRING_CST);
1512 TREE_STRING_LENGTH (s) = len;
1513 TREE_STRING_POINTER (s) = obstack_copy0 (saveable_obstack, str, len);
1517 /* Return a newly constructed COMPLEX_CST node whose value is
1518 specified by the real and imaginary parts REAL and IMAG.
1519 Both REAL and IMAG should be constant nodes. TYPE, if specified,
1520 will be the type of the COMPLEX_CST; otherwise a new type will be made. */
1523 build_complex (type, real, imag)
1527 register tree t = make_node (COMPLEX_CST);
1529 TREE_REALPART (t) = real;
1530 TREE_IMAGPART (t) = imag;
1531 TREE_TYPE (t) = type ? type : build_complex_type (TREE_TYPE (real));
1532 TREE_OVERFLOW (t) = TREE_OVERFLOW (real) | TREE_OVERFLOW (imag);
1533 TREE_CONSTANT_OVERFLOW (t)
1534 = TREE_CONSTANT_OVERFLOW (real) | TREE_CONSTANT_OVERFLOW (imag);
1538 /* Build a newly constructed TREE_VEC node of length LEN. */
1545 register int length = (len-1) * sizeof (tree) + sizeof (struct tree_vec);
1546 register struct obstack *obstack = current_obstack;
1549 #ifdef GATHER_STATISTICS
1550 tree_node_counts[(int)vec_kind]++;
1551 tree_node_sizes[(int)vec_kind] += length;
1554 t = (tree) obstack_alloc (obstack, length);
1556 for (i = (length / sizeof (int)) - 1; i >= 0; i--)
1559 TREE_SET_CODE (t, TREE_VEC);
1560 TREE_VEC_LENGTH (t) = len;
1561 if (obstack == &permanent_obstack)
1562 TREE_PERMANENT (t) = 1;
1567 /* Return 1 if EXPR is the integer constant zero or a complex constant
1571 integer_zerop (expr)
1576 return ((TREE_CODE (expr) == INTEGER_CST
1577 && ! TREE_CONSTANT_OVERFLOW (expr)
1578 && TREE_INT_CST_LOW (expr) == 0
1579 && TREE_INT_CST_HIGH (expr) == 0)
1580 || (TREE_CODE (expr) == COMPLEX_CST
1581 && integer_zerop (TREE_REALPART (expr))
1582 && integer_zerop (TREE_IMAGPART (expr))));
1585 /* Return 1 if EXPR is the integer constant one or the corresponding
1586 complex constant. */
1594 return ((TREE_CODE (expr) == INTEGER_CST
1595 && ! TREE_CONSTANT_OVERFLOW (expr)
1596 && TREE_INT_CST_LOW (expr) == 1
1597 && TREE_INT_CST_HIGH (expr) == 0)
1598 || (TREE_CODE (expr) == COMPLEX_CST
1599 && integer_onep (TREE_REALPART (expr))
1600 && integer_zerop (TREE_IMAGPART (expr))));
1603 /* Return 1 if EXPR is an integer containing all 1's in as much precision as
1604 it contains. Likewise for the corresponding complex constant. */
1607 integer_all_onesp (expr)
1615 if (TREE_CODE (expr) == COMPLEX_CST
1616 && integer_all_onesp (TREE_REALPART (expr))
1617 && integer_zerop (TREE_IMAGPART (expr)))
1620 else if (TREE_CODE (expr) != INTEGER_CST
1621 || TREE_CONSTANT_OVERFLOW (expr))
1624 uns = TREE_UNSIGNED (TREE_TYPE (expr));
1626 return TREE_INT_CST_LOW (expr) == -1 && TREE_INT_CST_HIGH (expr) == -1;
1628 /* Note that using TYPE_PRECISION here is wrong. We care about the
1629 actual bits, not the (arbitrary) range of the type. */
1630 prec = GET_MODE_BITSIZE (TYPE_MODE (TREE_TYPE (expr)));
1631 if (prec >= HOST_BITS_PER_WIDE_INT)
1633 int high_value, shift_amount;
1635 shift_amount = prec - HOST_BITS_PER_WIDE_INT;
1637 if (shift_amount > HOST_BITS_PER_WIDE_INT)
1638 /* Can not handle precisions greater than twice the host int size. */
1640 else if (shift_amount == HOST_BITS_PER_WIDE_INT)
1641 /* Shifting by the host word size is undefined according to the ANSI
1642 standard, so we must handle this as a special case. */
1645 high_value = ((HOST_WIDE_INT) 1 << shift_amount) - 1;
1647 return TREE_INT_CST_LOW (expr) == -1
1648 && TREE_INT_CST_HIGH (expr) == high_value;
1651 return TREE_INT_CST_LOW (expr) == ((HOST_WIDE_INT) 1 << prec) - 1;
1654 /* Return 1 if EXPR is an integer constant that is a power of 2 (i.e., has only
1658 integer_pow2p (expr)
1662 HOST_WIDE_INT high, low;
1666 if (TREE_CODE (expr) == COMPLEX_CST
1667 && integer_pow2p (TREE_REALPART (expr))
1668 && integer_zerop (TREE_IMAGPART (expr)))
1671 if (TREE_CODE (expr) != INTEGER_CST || TREE_CONSTANT_OVERFLOW (expr))
1674 prec = (POINTER_TYPE_P (TREE_TYPE (expr))
1675 ? POINTER_SIZE : TYPE_PRECISION (TREE_TYPE (expr)));
1676 high = TREE_INT_CST_HIGH (expr);
1677 low = TREE_INT_CST_LOW (expr);
1679 /* First clear all bits that are beyond the type's precision in case
1680 we've been sign extended. */
1682 if (prec == 2 * HOST_BITS_PER_WIDE_INT)
1684 else if (prec > HOST_BITS_PER_WIDE_INT)
1685 high &= ~((HOST_WIDE_INT) (-1) << (prec - HOST_BITS_PER_WIDE_INT));
1689 if (prec < HOST_BITS_PER_WIDE_INT)
1690 low &= ~((HOST_WIDE_INT) (-1) << prec);
1693 if (high == 0 && low == 0)
1696 return ((high == 0 && (low & (low - 1)) == 0)
1697 || (low == 0 && (high & (high - 1)) == 0));
1700 /* Return the power of two represented by a tree node known to be a
1708 HOST_WIDE_INT high, low;
1712 if (TREE_CODE (expr) == COMPLEX_CST)
1713 return tree_log2 (TREE_REALPART (expr));
1715 prec = (POINTER_TYPE_P (TREE_TYPE (expr))
1716 ? POINTER_SIZE : TYPE_PRECISION (TREE_TYPE (expr)));
1718 high = TREE_INT_CST_HIGH (expr);
1719 low = TREE_INT_CST_LOW (expr);
1721 /* First clear all bits that are beyond the type's precision in case
1722 we've been sign extended. */
1724 if (prec == 2 * HOST_BITS_PER_WIDE_INT)
1726 else if (prec > HOST_BITS_PER_WIDE_INT)
1727 high &= ~((HOST_WIDE_INT) (-1) << (prec - HOST_BITS_PER_WIDE_INT));
1731 if (prec < HOST_BITS_PER_WIDE_INT)
1732 low &= ~((HOST_WIDE_INT) (-1) << prec);
1735 return (high != 0 ? HOST_BITS_PER_WIDE_INT + exact_log2 (high)
1736 : exact_log2 (low));
1739 /* Return 1 if EXPR is the real constant zero. */
1747 return ((TREE_CODE (expr) == REAL_CST
1748 && ! TREE_CONSTANT_OVERFLOW (expr)
1749 && REAL_VALUES_EQUAL (TREE_REAL_CST (expr), dconst0))
1750 || (TREE_CODE (expr) == COMPLEX_CST
1751 && real_zerop (TREE_REALPART (expr))
1752 && real_zerop (TREE_IMAGPART (expr))));
1755 /* Return 1 if EXPR is the real constant one in real or complex form. */
1763 return ((TREE_CODE (expr) == REAL_CST
1764 && ! TREE_CONSTANT_OVERFLOW (expr)
1765 && REAL_VALUES_EQUAL (TREE_REAL_CST (expr), dconst1))
1766 || (TREE_CODE (expr) == COMPLEX_CST
1767 && real_onep (TREE_REALPART (expr))
1768 && real_zerop (TREE_IMAGPART (expr))));
1771 /* Return 1 if EXPR is the real constant two. */
1779 return ((TREE_CODE (expr) == REAL_CST
1780 && ! TREE_CONSTANT_OVERFLOW (expr)
1781 && REAL_VALUES_EQUAL (TREE_REAL_CST (expr), dconst2))
1782 || (TREE_CODE (expr) == COMPLEX_CST
1783 && real_twop (TREE_REALPART (expr))
1784 && real_zerop (TREE_IMAGPART (expr))));
1787 /* Nonzero if EXP is a constant or a cast of a constant. */
1790 really_constant_p (exp)
1793 /* This is not quite the same as STRIP_NOPS. It does more. */
1794 while (TREE_CODE (exp) == NOP_EXPR
1795 || TREE_CODE (exp) == CONVERT_EXPR
1796 || TREE_CODE (exp) == NON_LVALUE_EXPR)
1797 exp = TREE_OPERAND (exp, 0);
1798 return TREE_CONSTANT (exp);
1801 /* Return first list element whose TREE_VALUE is ELEM.
1802 Return 0 if ELEM is not in LIST. */
1805 value_member (elem, list)
1810 if (elem == TREE_VALUE (list))
1812 list = TREE_CHAIN (list);
1817 /* Return first list element whose TREE_PURPOSE is ELEM.
1818 Return 0 if ELEM is not in LIST. */
1821 purpose_member (elem, list)
1826 if (elem == TREE_PURPOSE (list))
1828 list = TREE_CHAIN (list);
1833 /* Return first list element whose BINFO_TYPE is ELEM.
1834 Return 0 if ELEM is not in LIST. */
1837 binfo_member (elem, list)
1842 if (elem == BINFO_TYPE (list))
1844 list = TREE_CHAIN (list);
1849 /* Return nonzero if ELEM is part of the chain CHAIN. */
1852 chain_member (elem, chain)
1859 chain = TREE_CHAIN (chain);
1865 /* Return nonzero if ELEM is equal to TREE_VALUE (CHAIN) for any piece of
1867 /* ??? This function was added for machine specific attributes but is no
1868 longer used. It could be deleted if we could confirm all front ends
1872 chain_member_value (elem, chain)
1877 if (elem == TREE_VALUE (chain))
1879 chain = TREE_CHAIN (chain);
1885 /* Return nonzero if ELEM is equal to TREE_PURPOSE (CHAIN)
1886 for any piece of chain CHAIN. */
1887 /* ??? This function was added for machine specific attributes but is no
1888 longer used. It could be deleted if we could confirm all front ends
1892 chain_member_purpose (elem, chain)
1897 if (elem == TREE_PURPOSE (chain))
1899 chain = TREE_CHAIN (chain);
1905 /* Return the length of a chain of nodes chained through TREE_CHAIN.
1906 We expect a null pointer to mark the end of the chain.
1907 This is the Lisp primitive `length'. */
1914 register int len = 0;
1916 for (tail = t; tail; tail = TREE_CHAIN (tail))
1922 /* Concatenate two chains of nodes (chained through TREE_CHAIN)
1923 by modifying the last node in chain 1 to point to chain 2.
1924 This is the Lisp primitive `nconc'. */
1936 for (t1 = op1; TREE_CHAIN (t1); t1 = TREE_CHAIN (t1))
1938 TREE_CHAIN (t1) = op2;
1939 for (t2 = op2; t2; t2 = TREE_CHAIN (t2))
1941 abort (); /* Circularity created. */
1947 /* Return the last node in a chain of nodes (chained through TREE_CHAIN). */
1951 register tree chain;
1955 while ((next = TREE_CHAIN (chain)))
1960 /* Reverse the order of elements in the chain T,
1961 and return the new head of the chain (old last element). */
1967 register tree prev = 0, decl, next;
1968 for (decl = t; decl; decl = next)
1970 next = TREE_CHAIN (decl);
1971 TREE_CHAIN (decl) = prev;
1977 /* Given a chain CHAIN of tree nodes,
1978 construct and return a list of those nodes. */
1984 tree result = NULL_TREE;
1985 tree in_tail = chain;
1986 tree out_tail = NULL_TREE;
1990 tree next = tree_cons (NULL_TREE, in_tail, NULL_TREE);
1992 TREE_CHAIN (out_tail) = next;
1996 in_tail = TREE_CHAIN (in_tail);
2002 /* Return a newly created TREE_LIST node whose
2003 purpose and value fields are PARM and VALUE. */
2006 build_tree_list (parm, value)
2009 register tree t = make_node (TREE_LIST);
2010 TREE_PURPOSE (t) = parm;
2011 TREE_VALUE (t) = value;
2015 /* Similar, but build on the temp_decl_obstack. */
2018 build_decl_list (parm, value)
2022 register struct obstack *ambient_obstack = current_obstack;
2023 current_obstack = &temp_decl_obstack;
2024 node = build_tree_list (parm, value);
2025 current_obstack = ambient_obstack;
2029 /* Similar, but build on the expression_obstack. */
2032 build_expr_list (parm, value)
2036 register struct obstack *ambient_obstack = current_obstack;
2037 current_obstack = expression_obstack;
2038 node = build_tree_list (parm, value);
2039 current_obstack = ambient_obstack;
2043 /* Return a newly created TREE_LIST node whose
2044 purpose and value fields are PARM and VALUE
2045 and whose TREE_CHAIN is CHAIN. */
2048 tree_cons (purpose, value, chain)
2049 tree purpose, value, chain;
2052 register tree node = make_node (TREE_LIST);
2055 register tree node = (tree) obstack_alloc (current_obstack, sizeof (struct tree_list));
2056 #ifdef GATHER_STATISTICS
2057 tree_node_counts[(int)x_kind]++;
2058 tree_node_sizes[(int)x_kind] += sizeof (struct tree_list);
2061 for (i = (sizeof (struct tree_common) / sizeof (int)) - 1; i >= 0; i--)
2062 ((int *) node)[i] = 0;
2064 TREE_SET_CODE (node, TREE_LIST);
2065 if (current_obstack == &permanent_obstack)
2066 TREE_PERMANENT (node) = 1;
2069 TREE_CHAIN (node) = chain;
2070 TREE_PURPOSE (node) = purpose;
2071 TREE_VALUE (node) = value;
2075 /* Similar, but build on the temp_decl_obstack. */
2078 decl_tree_cons (purpose, value, chain)
2079 tree purpose, value, chain;
2082 register struct obstack *ambient_obstack = current_obstack;
2083 current_obstack = &temp_decl_obstack;
2084 node = tree_cons (purpose, value, chain);
2085 current_obstack = ambient_obstack;
2089 /* Similar, but build on the expression_obstack. */
2092 expr_tree_cons (purpose, value, chain)
2093 tree purpose, value, chain;
2096 register struct obstack *ambient_obstack = current_obstack;
2097 current_obstack = expression_obstack;
2098 node = tree_cons (purpose, value, chain);
2099 current_obstack = ambient_obstack;
2103 /* Same as `tree_cons' but make a permanent object. */
2106 perm_tree_cons (purpose, value, chain)
2107 tree purpose, value, chain;
2110 register struct obstack *ambient_obstack = current_obstack;
2111 current_obstack = &permanent_obstack;
2113 node = tree_cons (purpose, value, chain);
2114 current_obstack = ambient_obstack;
2118 /* Same as `tree_cons', but make this node temporary, regardless. */
2121 temp_tree_cons (purpose, value, chain)
2122 tree purpose, value, chain;
2125 register struct obstack *ambient_obstack = current_obstack;
2126 current_obstack = &temporary_obstack;
2128 node = tree_cons (purpose, value, chain);
2129 current_obstack = ambient_obstack;
2133 /* Same as `tree_cons', but save this node if the function's RTL is saved. */
2136 saveable_tree_cons (purpose, value, chain)
2137 tree purpose, value, chain;
2140 register struct obstack *ambient_obstack = current_obstack;
2141 current_obstack = saveable_obstack;
2143 node = tree_cons (purpose, value, chain);
2144 current_obstack = ambient_obstack;
2148 /* Return the size nominally occupied by an object of type TYPE
2149 when it resides in memory. The value is measured in units of bytes,
2150 and its data type is that normally used for type sizes
2151 (which is the first type created by make_signed_type or
2152 make_unsigned_type). */
2155 size_in_bytes (type)
2160 if (type == error_mark_node)
2161 return integer_zero_node;
2162 type = TYPE_MAIN_VARIANT (type);
2163 if (TYPE_SIZE (type) == 0)
2165 incomplete_type_error (NULL_TREE, type);
2166 return integer_zero_node;
2168 t = size_binop (CEIL_DIV_EXPR, TYPE_SIZE (type),
2169 size_int (BITS_PER_UNIT));
2170 if (TREE_CODE (t) == INTEGER_CST)
2171 force_fit_type (t, 0);
2175 /* Return the size of TYPE (in bytes) as a wide integer
2176 or return -1 if the size can vary or is larger than an integer. */
2179 int_size_in_bytes (type)
2184 if (type == error_mark_node)
2187 type = TYPE_MAIN_VARIANT (type);
2188 if (TYPE_SIZE (type) == 0
2189 || TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
2192 if (TREE_INT_CST_HIGH (TYPE_SIZE (type)) == 0)
2193 return ((TREE_INT_CST_LOW (TYPE_SIZE (type)) + BITS_PER_UNIT - 1)
2196 t = size_binop (CEIL_DIV_EXPR, TYPE_SIZE (type), size_int (BITS_PER_UNIT));
2197 if (TREE_CODE (t) != INTEGER_CST || TREE_INT_CST_HIGH (t) != 0)
2200 return TREE_INT_CST_LOW (t);
2203 /* Return, as a tree node, the number of elements for TYPE (which is an
2204 ARRAY_TYPE) minus one. This counts only elements of the top array.
2206 Don't let any SAVE_EXPRs escape; if we are called as part of a cleanup
2207 action, they would get unsaved. */
2210 array_type_nelts (type)
2213 tree index_type, min, max;
2215 /* If they did it with unspecified bounds, then we should have already
2216 given an error about it before we got here. */
2217 if (! TYPE_DOMAIN (type))
2218 return error_mark_node;
2220 index_type = TYPE_DOMAIN (type);
2221 min = TYPE_MIN_VALUE (index_type);
2222 max = TYPE_MAX_VALUE (index_type);
2224 if (! TREE_CONSTANT (min))
2227 if (TREE_CODE (min) == SAVE_EXPR)
2228 min = build (RTL_EXPR, TREE_TYPE (TYPE_MIN_VALUE (index_type)), 0,
2229 SAVE_EXPR_RTL (min));
2231 min = TYPE_MIN_VALUE (index_type);
2234 if (! TREE_CONSTANT (max))
2237 if (TREE_CODE (max) == SAVE_EXPR)
2238 max = build (RTL_EXPR, TREE_TYPE (TYPE_MAX_VALUE (index_type)), 0,
2239 SAVE_EXPR_RTL (max));
2241 max = TYPE_MAX_VALUE (index_type);
2244 return (integer_zerop (min)
2246 : fold (build (MINUS_EXPR, TREE_TYPE (max), max, min)));
2249 /* Return nonzero if arg is static -- a reference to an object in
2250 static storage. This is not the same as the C meaning of `static'. */
2256 switch (TREE_CODE (arg))
2259 /* Nested functions aren't static, since taking their address
2260 involves a trampoline. */
2261 return decl_function_context (arg) == 0 || DECL_NO_STATIC_CHAIN (arg);
2263 return TREE_STATIC (arg) || DECL_EXTERNAL (arg);
2266 return TREE_STATIC (arg);
2271 /* If we are referencing a bitfield, we can't evaluate an
2272 ADDR_EXPR at compile time and so it isn't a constant. */
2274 return (! DECL_BIT_FIELD (TREE_OPERAND (arg, 1))
2275 && staticp (TREE_OPERAND (arg, 0)));
2281 /* This case is technically correct, but results in setting
2282 TREE_CONSTANT on ADDR_EXPRs that cannot be evaluated at
2285 return TREE_CONSTANT (TREE_OPERAND (arg, 0));
2289 if (TREE_CODE (TYPE_SIZE (TREE_TYPE (arg))) == INTEGER_CST
2290 && TREE_CODE (TREE_OPERAND (arg, 1)) == INTEGER_CST)
2291 return staticp (TREE_OPERAND (arg, 0));
2298 /* Wrap a SAVE_EXPR around EXPR, if appropriate.
2299 Do this to any expression which may be used in more than one place,
2300 but must be evaluated only once.
2302 Normally, expand_expr would reevaluate the expression each time.
2303 Calling save_expr produces something that is evaluated and recorded
2304 the first time expand_expr is called on it. Subsequent calls to
2305 expand_expr just reuse the recorded value.
2307 The call to expand_expr that generates code that actually computes
2308 the value is the first call *at compile time*. Subsequent calls
2309 *at compile time* generate code to use the saved value.
2310 This produces correct result provided that *at run time* control
2311 always flows through the insns made by the first expand_expr
2312 before reaching the other places where the save_expr was evaluated.
2313 You, the caller of save_expr, must make sure this is so.
2315 Constants, and certain read-only nodes, are returned with no
2316 SAVE_EXPR because that is safe. Expressions containing placeholders
2317 are not touched; see tree.def for an explanation of what these
2324 register tree t = fold (expr);
2326 /* We don't care about whether this can be used as an lvalue in this
2328 while (TREE_CODE (t) == NON_LVALUE_EXPR)
2329 t = TREE_OPERAND (t, 0);
2331 /* If the tree evaluates to a constant, then we don't want to hide that
2332 fact (i.e. this allows further folding, and direct checks for constants).
2333 However, a read-only object that has side effects cannot be bypassed.
2334 Since it is no problem to reevaluate literals, we just return the
2337 if (TREE_CONSTANT (t) || (TREE_READONLY (t) && ! TREE_SIDE_EFFECTS (t))
2338 || TREE_CODE (t) == SAVE_EXPR || TREE_CODE (t) == ERROR_MARK)
2341 /* If T contains a PLACEHOLDER_EXPR, we must evaluate it each time, since
2342 it means that the size or offset of some field of an object depends on
2343 the value within another field.
2345 Note that it must not be the case that T contains both a PLACEHOLDER_EXPR
2346 and some variable since it would then need to be both evaluated once and
2347 evaluated more than once. Front-ends must assure this case cannot
2348 happen by surrounding any such subexpressions in their own SAVE_EXPR
2349 and forcing evaluation at the proper time. */
2350 if (contains_placeholder_p (t))
2353 t = build (SAVE_EXPR, TREE_TYPE (expr), t, current_function_decl, NULL_TREE);
2355 /* This expression might be placed ahead of a jump to ensure that the
2356 value was computed on both sides of the jump. So make sure it isn't
2357 eliminated as dead. */
2358 TREE_SIDE_EFFECTS (t) = 1;
2362 /* Arrange for an expression to be expanded multiple independent
2363 times. This is useful for cleanup actions, as the backend can
2364 expand them multiple times in different places. */
2372 /* If this is already protected, no sense in protecting it again. */
2373 if (TREE_CODE (expr) == UNSAVE_EXPR)
2376 t = build1 (UNSAVE_EXPR, TREE_TYPE (expr), expr);
2377 TREE_SIDE_EFFECTS (t) = TREE_SIDE_EFFECTS (expr);
2381 /* Returns the index of the first non-tree operand for CODE, or the number
2382 of operands if all are trees. */
2386 enum tree_code code;
2396 case WITH_CLEANUP_EXPR:
2397 /* Should be defined to be 2. */
2399 case METHOD_CALL_EXPR:
2402 return tree_code_length [(int) code];
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 = first_rtl_op (code);
2425 SAVE_EXPR_RTL (expr) = 0;
2429 TREE_OPERAND (expr, 1) = TREE_OPERAND (expr, 3);
2430 TREE_OPERAND (expr, 3) = NULL_TREE;
2434 /* I don't yet know how to emit a sequence multiple times. */
2435 if (RTL_EXPR_SEQUENCE (expr) != 0)
2440 CALL_EXPR_RTL (expr) = 0;
2441 if (TREE_OPERAND (expr, 1)
2442 && TREE_CODE (TREE_OPERAND (expr, 1)) == TREE_LIST)
2444 tree exp = TREE_OPERAND (expr, 1);
2447 unsave_expr_now (TREE_VALUE (exp));
2448 exp = TREE_CHAIN (exp);
2457 switch (TREE_CODE_CLASS (code))
2459 case 'c': /* a constant */
2460 case 't': /* a type node */
2461 case 'x': /* something random, like an identifier or an ERROR_MARK. */
2462 case 'd': /* A decl node */
2463 case 'b': /* A block node */
2466 case 'e': /* an expression */
2467 case 'r': /* a reference */
2468 case 's': /* an expression with side effects */
2469 case '<': /* a comparison expression */
2470 case '2': /* a binary arithmetic expression */
2471 case '1': /* a unary arithmetic expression */
2472 for (i = first_rtl - 1; i >= 0; i--)
2473 unsave_expr_now (TREE_OPERAND (expr, i));
2481 /* Return 1 if EXP contains a PLACEHOLDER_EXPR; i.e., if it represents a size
2482 or offset that depends on a field within a record. */
2485 contains_placeholder_p (exp)
2488 register enum tree_code code = TREE_CODE (exp);
2491 /* If we have a WITH_RECORD_EXPR, it "cancels" any PLACEHOLDER_EXPR
2492 in it since it is supplying a value for it. */
2493 if (code == WITH_RECORD_EXPR)
2495 else if (code == PLACEHOLDER_EXPR)
2498 switch (TREE_CODE_CLASS (code))
2501 /* Don't look at any PLACEHOLDER_EXPRs that might be in index or bit
2502 position computations since they will be converted into a
2503 WITH_RECORD_EXPR involving the reference, which will assume
2504 here will be valid. */
2505 return contains_placeholder_p (TREE_OPERAND (exp, 0));
2508 if (code == TREE_LIST)
2509 return (contains_placeholder_p (TREE_VALUE (exp))
2510 || (TREE_CHAIN (exp) != 0
2511 && contains_placeholder_p (TREE_CHAIN (exp))));
2520 /* Ignoring the first operand isn't quite right, but works best. */
2521 return contains_placeholder_p (TREE_OPERAND (exp, 1));
2528 return (contains_placeholder_p (TREE_OPERAND (exp, 0))
2529 || contains_placeholder_p (TREE_OPERAND (exp, 1))
2530 || contains_placeholder_p (TREE_OPERAND (exp, 2)));
2533 /* If we already know this doesn't have a placeholder, don't
2535 if (SAVE_EXPR_NOPLACEHOLDER (exp) || SAVE_EXPR_RTL (exp) != 0)
2538 SAVE_EXPR_NOPLACEHOLDER (exp) = 1;
2539 result = contains_placeholder_p (TREE_OPERAND (exp, 0));
2541 SAVE_EXPR_NOPLACEHOLDER (exp) = 0;
2546 return (TREE_OPERAND (exp, 1) != 0
2547 && contains_placeholder_p (TREE_OPERAND (exp, 1)));
2553 switch (tree_code_length[(int) code])
2556 return contains_placeholder_p (TREE_OPERAND (exp, 0));
2558 return (contains_placeholder_p (TREE_OPERAND (exp, 0))
2559 || contains_placeholder_p (TREE_OPERAND (exp, 1)));
2570 /* Return 1 if EXP contains any expressions that produce cleanups for an
2571 outer scope to deal with. Used by fold. */
2579 if (! TREE_SIDE_EFFECTS (exp))
2582 switch (TREE_CODE (exp))
2585 case WITH_CLEANUP_EXPR:
2588 case CLEANUP_POINT_EXPR:
2592 for (exp = TREE_OPERAND (exp, 1); exp; exp = TREE_CHAIN (exp))
2594 cmp = has_cleanups (TREE_VALUE (exp));
2604 /* This general rule works for most tree codes. All exceptions should be
2605 handled above. If this is a language-specific tree code, we can't
2606 trust what might be in the operand, so say we don't know
2608 if ((int) TREE_CODE (exp) >= (int) LAST_AND_UNUSED_TREE_CODE)
2611 nops = first_rtl_op (TREE_CODE (exp));
2612 for (i = 0; i < nops; i++)
2613 if (TREE_OPERAND (exp, i) != 0)
2615 int type = TREE_CODE_CLASS (TREE_CODE (TREE_OPERAND (exp, i)));
2616 if (type == 'e' || type == '<' || type == '1' || type == '2'
2617 || type == 'r' || type == 's')
2619 cmp = has_cleanups (TREE_OPERAND (exp, i));
2628 /* Given a tree EXP, a FIELD_DECL F, and a replacement value R,
2629 return a tree with all occurrences of references to F in a
2630 PLACEHOLDER_EXPR replaced by R. Note that we assume here that EXP
2631 contains only arithmetic expressions or a CALL_EXPR with a
2632 PLACEHOLDER_EXPR occurring only in its arglist. */
2635 substitute_in_expr (exp, f, r)
2640 enum tree_code code = TREE_CODE (exp);
2645 switch (TREE_CODE_CLASS (code))
2652 if (code == PLACEHOLDER_EXPR)
2654 else if (code == TREE_LIST)
2656 op0 = (TREE_CHAIN (exp) == 0
2657 ? 0 : substitute_in_expr (TREE_CHAIN (exp), f, r));
2658 op1 = substitute_in_expr (TREE_VALUE (exp), f, r);
2659 if (op0 == TREE_CHAIN (exp) && op1 == TREE_VALUE (exp))
2662 return tree_cons (TREE_PURPOSE (exp), op1, op0);
2671 switch (tree_code_length[(int) code])
2674 op0 = substitute_in_expr (TREE_OPERAND (exp, 0), f, r);
2675 if (op0 == TREE_OPERAND (exp, 0))
2678 new = fold (build1 (code, TREE_TYPE (exp), op0));
2682 /* An RTL_EXPR cannot contain a PLACEHOLDER_EXPR; a CONSTRUCTOR
2683 could, but we don't support it. */
2684 if (code == RTL_EXPR)
2686 else if (code == CONSTRUCTOR)
2689 op0 = substitute_in_expr (TREE_OPERAND (exp, 0), f, r);
2690 op1 = substitute_in_expr (TREE_OPERAND (exp, 1), f, r);
2691 if (op0 == TREE_OPERAND (exp, 0) && op1 == TREE_OPERAND (exp, 1))
2694 new = fold (build (code, TREE_TYPE (exp), op0, op1));
2698 /* It cannot be that anything inside a SAVE_EXPR contains a
2699 PLACEHOLDER_EXPR. */
2700 if (code == SAVE_EXPR)
2703 else if (code == CALL_EXPR)
2705 op1 = substitute_in_expr (TREE_OPERAND (exp, 1), f, r);
2706 if (op1 == TREE_OPERAND (exp, 1))
2709 return build (code, TREE_TYPE (exp),
2710 TREE_OPERAND (exp, 0), op1, NULL_TREE);
2713 else if (code != COND_EXPR)
2716 op0 = substitute_in_expr (TREE_OPERAND (exp, 0), f, r);
2717 op1 = substitute_in_expr (TREE_OPERAND (exp, 1), f, r);
2718 op2 = substitute_in_expr (TREE_OPERAND (exp, 2), f, r);
2719 if (op0 == TREE_OPERAND (exp, 0) && op1 == TREE_OPERAND (exp, 1)
2720 && op2 == TREE_OPERAND (exp, 2))
2723 new = fold (build (code, TREE_TYPE (exp), op0, op1, op2));
2736 /* If this expression is getting a value from a PLACEHOLDER_EXPR
2737 and it is the right field, replace it with R. */
2738 for (inner = TREE_OPERAND (exp, 0);
2739 TREE_CODE_CLASS (TREE_CODE (inner)) == 'r';
2740 inner = TREE_OPERAND (inner, 0))
2742 if (TREE_CODE (inner) == PLACEHOLDER_EXPR
2743 && TREE_OPERAND (exp, 1) == f)
2746 /* If this expression hasn't been completed let, leave it
2748 if (TREE_CODE (inner) == PLACEHOLDER_EXPR
2749 && TREE_TYPE (inner) == 0)
2752 op0 = substitute_in_expr (TREE_OPERAND (exp, 0), f, r);
2753 if (op0 == TREE_OPERAND (exp, 0))
2756 new = fold (build (code, TREE_TYPE (exp), op0,
2757 TREE_OPERAND (exp, 1)));
2761 op0 = substitute_in_expr (TREE_OPERAND (exp, 0), f, r);
2762 op1 = substitute_in_expr (TREE_OPERAND (exp, 1), f, r);
2763 op2 = substitute_in_expr (TREE_OPERAND (exp, 2), f, r);
2764 if (op0 == TREE_OPERAND (exp, 0) && op1 == TREE_OPERAND (exp, 1)
2765 && op2 == TREE_OPERAND (exp, 2))
2768 new = fold (build (code, TREE_TYPE (exp), op0, op1, op2));
2773 op0 = substitute_in_expr (TREE_OPERAND (exp, 0), f, r);
2774 if (op0 == TREE_OPERAND (exp, 0))
2777 new = fold (build1 (code, TREE_TYPE (exp), op0));
2789 TREE_READONLY (new) = TREE_READONLY (exp);
2793 /* Stabilize a reference so that we can use it any number of times
2794 without causing its operands to be evaluated more than once.
2795 Returns the stabilized reference. This works by means of save_expr,
2796 so see the caveats in the comments about save_expr.
2798 Also allows conversion expressions whose operands are references.
2799 Any other kind of expression is returned unchanged. */
2802 stabilize_reference (ref)
2805 register tree result;
2806 register enum tree_code code = TREE_CODE (ref);
2813 /* No action is needed in this case. */
2819 case FIX_TRUNC_EXPR:
2820 case FIX_FLOOR_EXPR:
2821 case FIX_ROUND_EXPR:
2823 result = build_nt (code, stabilize_reference (TREE_OPERAND (ref, 0)));
2827 result = build_nt (INDIRECT_REF,
2828 stabilize_reference_1 (TREE_OPERAND (ref, 0)));
2832 result = build_nt (COMPONENT_REF,
2833 stabilize_reference (TREE_OPERAND (ref, 0)),
2834 TREE_OPERAND (ref, 1));
2838 result = build_nt (BIT_FIELD_REF,
2839 stabilize_reference (TREE_OPERAND (ref, 0)),
2840 stabilize_reference_1 (TREE_OPERAND (ref, 1)),
2841 stabilize_reference_1 (TREE_OPERAND (ref, 2)));
2845 result = build_nt (ARRAY_REF,
2846 stabilize_reference (TREE_OPERAND (ref, 0)),
2847 stabilize_reference_1 (TREE_OPERAND (ref, 1)));
2851 /* We cannot wrap the first expression in a SAVE_EXPR, as then
2852 it wouldn't be ignored. This matters when dealing with
2854 return stabilize_reference_1 (ref);
2857 result = build1 (INDIRECT_REF, TREE_TYPE (ref),
2858 save_expr (build1 (ADDR_EXPR,
2859 build_pointer_type (TREE_TYPE (ref)),
2864 /* If arg isn't a kind of lvalue we recognize, make no change.
2865 Caller should recognize the error for an invalid lvalue. */
2870 return error_mark_node;
2873 TREE_TYPE (result) = TREE_TYPE (ref);
2874 TREE_READONLY (result) = TREE_READONLY (ref);
2875 TREE_SIDE_EFFECTS (result) = TREE_SIDE_EFFECTS (ref);
2876 TREE_THIS_VOLATILE (result) = TREE_THIS_VOLATILE (ref);
2877 TREE_RAISES (result) = TREE_RAISES (ref);
2882 /* Subroutine of stabilize_reference; this is called for subtrees of
2883 references. Any expression with side-effects must be put in a SAVE_EXPR
2884 to ensure that it is only evaluated once.
2886 We don't put SAVE_EXPR nodes around everything, because assigning very
2887 simple expressions to temporaries causes us to miss good opportunities
2888 for optimizations. Among other things, the opportunity to fold in the
2889 addition of a constant into an addressing mode often gets lost, e.g.
2890 "y[i+1] += x;". In general, we take the approach that we should not make
2891 an assignment unless we are forced into it - i.e., that any non-side effect
2892 operator should be allowed, and that cse should take care of coalescing
2893 multiple utterances of the same expression should that prove fruitful. */
2896 stabilize_reference_1 (e)
2899 register tree result;
2900 register enum tree_code code = TREE_CODE (e);
2902 /* We cannot ignore const expressions because it might be a reference
2903 to a const array but whose index contains side-effects. But we can
2904 ignore things that are actual constant or that already have been
2905 handled by this function. */
2907 if (TREE_CONSTANT (e) || code == SAVE_EXPR)
2910 switch (TREE_CODE_CLASS (code))
2920 /* If the expression has side-effects, then encase it in a SAVE_EXPR
2921 so that it will only be evaluated once. */
2922 /* The reference (r) and comparison (<) classes could be handled as
2923 below, but it is generally faster to only evaluate them once. */
2924 if (TREE_SIDE_EFFECTS (e))
2925 return save_expr (e);
2929 /* Constants need no processing. In fact, we should never reach
2934 /* Division is slow and tends to be compiled with jumps,
2935 especially the division by powers of 2 that is often
2936 found inside of an array reference. So do it just once. */
2937 if (code == TRUNC_DIV_EXPR || code == TRUNC_MOD_EXPR
2938 || code == FLOOR_DIV_EXPR || code == FLOOR_MOD_EXPR
2939 || code == CEIL_DIV_EXPR || code == CEIL_MOD_EXPR
2940 || code == ROUND_DIV_EXPR || code == ROUND_MOD_EXPR)
2941 return save_expr (e);
2942 /* Recursively stabilize each operand. */
2943 result = build_nt (code, stabilize_reference_1 (TREE_OPERAND (e, 0)),
2944 stabilize_reference_1 (TREE_OPERAND (e, 1)));
2948 /* Recursively stabilize each operand. */
2949 result = build_nt (code, stabilize_reference_1 (TREE_OPERAND (e, 0)));
2956 TREE_TYPE (result) = TREE_TYPE (e);
2957 TREE_READONLY (result) = TREE_READONLY (e);
2958 TREE_SIDE_EFFECTS (result) = TREE_SIDE_EFFECTS (e);
2959 TREE_THIS_VOLATILE (result) = TREE_THIS_VOLATILE (e);
2960 TREE_RAISES (result) = TREE_RAISES (e);
2965 /* Low-level constructors for expressions. */
2967 /* Build an expression of code CODE, data type TYPE,
2968 and operands as specified by the arguments ARG1 and following arguments.
2969 Expressions and reference nodes can be created this way.
2970 Constants, decls, types and misc nodes cannot be. */
2973 build VPROTO((enum tree_code code, tree tt, ...))
2976 enum tree_code code;
2981 register int length;
2987 code = va_arg (p, enum tree_code);
2988 tt = va_arg (p, tree);
2991 t = make_node (code);
2992 length = tree_code_length[(int) code];
2997 /* This is equivalent to the loop below, but faster. */
2998 register tree arg0 = va_arg (p, tree);
2999 register tree arg1 = va_arg (p, tree);
3000 TREE_OPERAND (t, 0) = arg0;
3001 TREE_OPERAND (t, 1) = arg1;
3002 if ((arg0 && TREE_SIDE_EFFECTS (arg0))
3003 || (arg1 && TREE_SIDE_EFFECTS (arg1)))
3004 TREE_SIDE_EFFECTS (t) = 1;
3006 = (arg0 && TREE_RAISES (arg0)) || (arg1 && TREE_RAISES (arg1));
3008 else if (length == 1)
3010 register tree arg0 = va_arg (p, tree);
3012 /* Call build1 for this! */
3013 if (TREE_CODE_CLASS (code) != 's')
3015 TREE_OPERAND (t, 0) = arg0;
3016 if (arg0 && TREE_SIDE_EFFECTS (arg0))
3017 TREE_SIDE_EFFECTS (t) = 1;
3018 TREE_RAISES (t) = (arg0 && TREE_RAISES (arg0));
3022 for (i = 0; i < length; i++)
3024 register tree operand = va_arg (p, tree);
3025 TREE_OPERAND (t, i) = operand;
3028 if (TREE_SIDE_EFFECTS (operand))
3029 TREE_SIDE_EFFECTS (t) = 1;
3030 if (TREE_RAISES (operand))
3031 TREE_RAISES (t) = 1;
3039 /* Same as above, but only builds for unary operators.
3040 Saves lions share of calls to `build'; cuts down use
3041 of varargs, which is expensive for RISC machines. */
3044 build1 (code, type, node)
3045 enum tree_code code;
3049 register struct obstack *obstack = expression_obstack;
3050 register int i, length;
3051 #ifdef GATHER_STATISTICS
3052 register tree_node_kind kind;
3056 #ifdef GATHER_STATISTICS
3057 if (TREE_CODE_CLASS (code) == 'r')
3063 length = sizeof (struct tree_exp);
3065 t = (tree) obstack_alloc (obstack, length);
3067 #ifdef GATHER_STATISTICS
3068 tree_node_counts[(int)kind]++;
3069 tree_node_sizes[(int)kind] += length;
3072 for (i = (length / sizeof (int)) - 1; i >= 0; i--)
3075 TREE_TYPE (t) = type;
3076 TREE_SET_CODE (t, code);
3078 if (obstack == &permanent_obstack)
3079 TREE_PERMANENT (t) = 1;
3081 TREE_OPERAND (t, 0) = node;
3084 if (TREE_SIDE_EFFECTS (node))
3085 TREE_SIDE_EFFECTS (t) = 1;
3086 if (TREE_RAISES (node))
3087 TREE_RAISES (t) = 1;
3093 /* Similar except don't specify the TREE_TYPE
3094 and leave the TREE_SIDE_EFFECTS as 0.
3095 It is permissible for arguments to be null,
3096 or even garbage if their values do not matter. */
3099 build_nt VPROTO((enum tree_code code, ...))
3102 enum tree_code code;
3106 register int length;
3112 code = va_arg (p, enum tree_code);
3115 t = make_node (code);
3116 length = tree_code_length[(int) code];
3118 for (i = 0; i < length; i++)
3119 TREE_OPERAND (t, i) = va_arg (p, tree);
3125 /* Similar to `build_nt', except we build
3126 on the temp_decl_obstack, regardless. */
3129 build_parse_node VPROTO((enum tree_code code, ...))
3132 enum tree_code code;
3134 register struct obstack *ambient_obstack = expression_obstack;
3137 register int length;
3143 code = va_arg (p, enum tree_code);
3146 expression_obstack = &temp_decl_obstack;
3148 t = make_node (code);
3149 length = tree_code_length[(int) code];
3151 for (i = 0; i < length; i++)
3152 TREE_OPERAND (t, i) = va_arg (p, tree);
3155 expression_obstack = ambient_obstack;
3160 /* Commented out because this wants to be done very
3161 differently. See cp-lex.c. */
3163 build_op_identifier (op1, op2)
3166 register tree t = make_node (OP_IDENTIFIER);
3167 TREE_PURPOSE (t) = op1;
3168 TREE_VALUE (t) = op2;
3173 /* Create a DECL_... node of code CODE, name NAME and data type TYPE.
3174 We do NOT enter this node in any sort of symbol table.
3176 layout_decl is used to set up the decl's storage layout.
3177 Other slots are initialized to 0 or null pointers. */
3180 build_decl (code, name, type)
3181 enum tree_code code;
3186 t = make_node (code);
3188 /* if (type == error_mark_node)
3189 type = integer_type_node; */
3190 /* That is not done, deliberately, so that having error_mark_node
3191 as the type can suppress useless errors in the use of this variable. */
3193 DECL_NAME (t) = name;
3194 DECL_ASSEMBLER_NAME (t) = name;
3195 TREE_TYPE (t) = type;
3197 if (code == VAR_DECL || code == PARM_DECL || code == RESULT_DECL)
3199 else if (code == FUNCTION_DECL)
3200 DECL_MODE (t) = FUNCTION_MODE;
3205 /* BLOCK nodes are used to represent the structure of binding contours
3206 and declarations, once those contours have been exited and their contents
3207 compiled. This information is used for outputting debugging info. */
3210 build_block (vars, tags, subblocks, supercontext, chain)
3211 tree vars, tags, subblocks, supercontext, chain;
3213 register tree block = make_node (BLOCK);
3214 BLOCK_VARS (block) = vars;
3215 BLOCK_TYPE_TAGS (block) = tags;
3216 BLOCK_SUBBLOCKS (block) = subblocks;
3217 BLOCK_SUPERCONTEXT (block) = supercontext;
3218 BLOCK_CHAIN (block) = chain;
3222 /* Return a declaration like DDECL except that its DECL_MACHINE_ATTRIBUTE
3226 build_decl_attribute_variant (ddecl, attribute)
3227 tree ddecl, attribute;
3229 DECL_MACHINE_ATTRIBUTES (ddecl) = attribute;
3233 /* Return a type like TTYPE except that its TYPE_ATTRIBUTE
3236 Record such modified types already made so we don't make duplicates. */
3239 build_type_attribute_variant (ttype, attribute)
3240 tree ttype, attribute;
3242 if ( ! attribute_list_equal (TYPE_ATTRIBUTES (ttype), attribute))
3244 register int hashcode;
3245 register struct obstack *ambient_obstack = current_obstack;
3248 if (ambient_obstack != &permanent_obstack)
3249 current_obstack = TYPE_OBSTACK (ttype);
3251 ntype = copy_node (ttype);
3252 current_obstack = ambient_obstack;
3254 TYPE_POINTER_TO (ntype) = 0;
3255 TYPE_REFERENCE_TO (ntype) = 0;
3256 TYPE_ATTRIBUTES (ntype) = attribute;
3258 /* Create a new main variant of TYPE. */
3259 TYPE_MAIN_VARIANT (ntype) = ntype;
3260 TYPE_NEXT_VARIANT (ntype) = 0;
3261 TYPE_READONLY (ntype) = TYPE_VOLATILE (ntype) = 0;
3263 hashcode = TYPE_HASH (TREE_CODE (ntype))
3264 + TYPE_HASH (TREE_TYPE (ntype))
3265 + attribute_hash_list (attribute);
3267 switch (TREE_CODE (ntype))
3270 hashcode += TYPE_HASH (TYPE_ARG_TYPES (ntype));
3273 hashcode += TYPE_HASH (TYPE_DOMAIN (ntype));
3276 hashcode += TYPE_HASH (TYPE_MAX_VALUE (ntype));
3279 hashcode += TYPE_HASH (TYPE_PRECISION (ntype));
3285 ntype = type_hash_canon (hashcode, ntype);
3286 ttype = build_type_variant (ntype, TYPE_READONLY (ttype),
3287 TYPE_VOLATILE (ttype));
3293 /* Return a 1 if ATTR_NAME and ATTR_ARGS is valid for either declaration DECL
3294 or type TYPE and 0 otherwise. Validity is determined the configuration
3295 macros VALID_MACHINE_DECL_ATTRIBUTE and VALID_MACHINE_TYPE_ATTRIBUTE. */
3298 valid_machine_attribute (attr_name, attr_args, decl, type)
3299 tree attr_name, attr_args;
3304 #ifdef VALID_MACHINE_DECL_ATTRIBUTE
3305 tree decl_attr_list = decl != 0 ? DECL_MACHINE_ATTRIBUTES (decl) : 0;
3307 #ifdef VALID_MACHINE_TYPE_ATTRIBUTE
3308 tree type_attr_list = TYPE_ATTRIBUTES (type);
3311 if (TREE_CODE (attr_name) != IDENTIFIER_NODE)
3314 #ifdef VALID_MACHINE_DECL_ATTRIBUTE
3316 && VALID_MACHINE_DECL_ATTRIBUTE (decl, decl_attr_list, attr_name, attr_args))
3318 tree attr = lookup_attribute (IDENTIFIER_POINTER (attr_name),
3321 if (attr != NULL_TREE)
3323 /* Override existing arguments. Declarations are unique so we can
3324 modify this in place. */
3325 TREE_VALUE (attr) = attr_args;
3329 decl_attr_list = tree_cons (attr_name, attr_args, decl_attr_list);
3330 decl = build_decl_attribute_variant (decl, decl_attr_list);
3337 #ifdef VALID_MACHINE_TYPE_ATTRIBUTE
3338 if (VALID_MACHINE_TYPE_ATTRIBUTE (type, type_attr_list, attr_name, attr_args))
3340 tree attr = lookup_attribute (IDENTIFIER_POINTER (attr_name),
3343 if (attr != NULL_TREE)
3345 /* Override existing arguments.
3346 ??? This currently works since attribute arguments are not
3347 included in `attribute_hash_list'. Something more complicated
3348 may be needed in the future. */
3349 TREE_VALUE (attr) = attr_args;
3353 type_attr_list = tree_cons (attr_name, attr_args, type_attr_list);
3354 type = build_type_attribute_variant (type, type_attr_list);
3357 TREE_TYPE (decl) = type;
3361 /* Handle putting a type attribute on pointer-to-function-type by putting
3362 the attribute on the function type. */
3363 else if (POINTER_TYPE_P (type)
3364 && TREE_CODE (TREE_TYPE (type)) == FUNCTION_TYPE
3365 && VALID_MACHINE_TYPE_ATTRIBUTE (TREE_TYPE (type), type_attr_list,
3366 attr_name, attr_args))
3368 tree inner_type = TREE_TYPE (type);
3369 tree inner_attr_list = TYPE_ATTRIBUTES (inner_type);
3370 tree attr = lookup_attribute (IDENTIFIER_POINTER (attr_name),
3373 if (attr != NULL_TREE)
3374 TREE_VALUE (attr) = attr_args;
3377 inner_attr_list = tree_cons (attr_name, attr_args, inner_attr_list);
3378 inner_type = build_type_attribute_variant (inner_type,
3383 TREE_TYPE (decl) = build_pointer_type (inner_type);
3392 /* Return non-zero if IDENT is a valid name for attribute ATTR,
3395 We try both `text' and `__text__', ATTR may be either one. */
3396 /* ??? It might be a reasonable simplification to require ATTR to be only
3397 `text'. One might then also require attribute lists to be stored in
3398 their canonicalized form. */
3401 is_attribute_p (attr, ident)
3405 int ident_len, attr_len;
3408 if (TREE_CODE (ident) != IDENTIFIER_NODE)
3411 if (strcmp (attr, IDENTIFIER_POINTER (ident)) == 0)
3414 p = IDENTIFIER_POINTER (ident);
3415 ident_len = strlen (p);
3416 attr_len = strlen (attr);
3418 /* If ATTR is `__text__', IDENT must be `text'; and vice versa. */
3422 || attr[attr_len - 2] != '_'
3423 || attr[attr_len - 1] != '_')
3425 if (ident_len == attr_len - 4
3426 && strncmp (attr + 2, p, attr_len - 4) == 0)
3431 if (ident_len == attr_len + 4
3432 && p[0] == '_' && p[1] == '_'
3433 && p[ident_len - 2] == '_' && p[ident_len - 1] == '_'
3434 && strncmp (attr, p + 2, attr_len) == 0)
3441 /* Given an attribute name and a list of attributes, return a pointer to the
3442 attribute's list element if the attribute is part of the list, or NULL_TREE
3446 lookup_attribute (attr_name, list)
3452 for (l = list; l; l = TREE_CHAIN (l))
3454 if (TREE_CODE (TREE_PURPOSE (l)) != IDENTIFIER_NODE)
3456 if (is_attribute_p (attr_name, TREE_PURPOSE (l)))
3463 /* Return an attribute list that is the union of a1 and a2. */
3466 merge_attributes (a1, a2)
3467 register tree a1, a2;
3471 /* Either one unset? Take the set one. */
3473 if (! (attributes = a1))
3476 /* One that completely contains the other? Take it. */
3478 else if (a2 && ! attribute_list_contained (a1, a2))
3480 if (attribute_list_contained (a2, a1))
3484 /* Pick the longest list, and hang on the other list. */
3485 /* ??? For the moment we punt on the issue of attrs with args. */
3487 if (list_length (a1) < list_length (a2))
3488 attributes = a2, a2 = a1;
3490 for (; a2; a2 = TREE_CHAIN (a2))
3491 if (lookup_attribute (IDENTIFIER_POINTER (TREE_PURPOSE (a2)),
3492 attributes) == NULL_TREE)
3494 a1 = copy_node (a2);
3495 TREE_CHAIN (a1) = attributes;
3503 /* Given types T1 and T2, merge their attributes and return
3507 merge_machine_type_attributes (t1, t2)
3510 #ifdef MERGE_MACHINE_TYPE_ATTRIBUTES
3511 return MERGE_MACHINE_TYPE_ATTRIBUTES (t1, t2);
3513 return merge_attributes (TYPE_ATTRIBUTES (t1),
3514 TYPE_ATTRIBUTES (t2));
3518 /* Given decls OLDDECL and NEWDECL, merge their attributes and return
3522 merge_machine_decl_attributes (olddecl, newdecl)
3523 tree olddecl, newdecl;
3525 #ifdef MERGE_MACHINE_DECL_ATTRIBUTES
3526 return MERGE_MACHINE_DECL_ATTRIBUTES (olddecl, newdecl);
3528 return merge_attributes (DECL_MACHINE_ATTRIBUTES (olddecl),
3529 DECL_MACHINE_ATTRIBUTES (newdecl));
3533 /* Return a type like TYPE except that its TYPE_READONLY is CONSTP
3534 and its TYPE_VOLATILE is VOLATILEP.
3536 Such variant types already made are recorded so that duplicates
3539 A variant types should never be used as the type of an expression.
3540 Always copy the variant information into the TREE_READONLY
3541 and TREE_THIS_VOLATILE of the expression, and then give the expression
3542 as its type the "main variant", the variant whose TYPE_READONLY
3543 and TYPE_VOLATILE are zero. Use TYPE_MAIN_VARIANT to find the
3547 build_type_variant (type, constp, volatilep)
3549 int constp, volatilep;
3553 /* Treat any nonzero argument as 1. */
3555 volatilep = !!volatilep;
3557 /* Search the chain of variants to see if there is already one there just
3558 like the one we need to have. If so, use that existing one. We must
3559 preserve the TYPE_NAME, since there is code that depends on this. */
3561 for (t = TYPE_MAIN_VARIANT (type); t; t = TYPE_NEXT_VARIANT (t))
3562 if (constp == TYPE_READONLY (t) && volatilep == TYPE_VOLATILE (t)
3563 && TYPE_NAME (t) == TYPE_NAME (type))
3566 /* We need a new one. */
3568 t = build_type_copy (type);
3569 TYPE_READONLY (t) = constp;
3570 TYPE_VOLATILE (t) = volatilep;
3575 /* Create a new variant of TYPE, equivalent but distinct.
3576 This is so the caller can modify it. */
3579 build_type_copy (type)
3582 register tree t, m = TYPE_MAIN_VARIANT (type);
3583 register struct obstack *ambient_obstack = current_obstack;
3585 current_obstack = TYPE_OBSTACK (type);
3586 t = copy_node (type);
3587 current_obstack = ambient_obstack;
3589 TYPE_POINTER_TO (t) = 0;
3590 TYPE_REFERENCE_TO (t) = 0;
3592 /* Add this type to the chain of variants of TYPE. */
3593 TYPE_NEXT_VARIANT (t) = TYPE_NEXT_VARIANT (m);
3594 TYPE_NEXT_VARIANT (m) = t;
3599 /* Hashing of types so that we don't make duplicates.
3600 The entry point is `type_hash_canon'. */
3602 /* Each hash table slot is a bucket containing a chain
3603 of these structures. */
3607 struct type_hash *next; /* Next structure in the bucket. */
3608 int hashcode; /* Hash code of this type. */
3609 tree type; /* The type recorded here. */
3612 /* Now here is the hash table. When recording a type, it is added
3613 to the slot whose index is the hash code mod the table size.
3614 Note that the hash table is used for several kinds of types
3615 (function types, array types and array index range types, for now).
3616 While all these live in the same table, they are completely independent,
3617 and the hash code is computed differently for each of these. */
3619 #define TYPE_HASH_SIZE 59
3620 struct type_hash *type_hash_table[TYPE_HASH_SIZE];
3622 /* Compute a hash code for a list of types (chain of TREE_LIST nodes
3623 with types in the TREE_VALUE slots), by adding the hash codes
3624 of the individual types. */
3627 type_hash_list (list)
3630 register int hashcode;
3632 for (hashcode = 0, tail = list; tail; tail = TREE_CHAIN (tail))
3633 hashcode += TYPE_HASH (TREE_VALUE (tail));
3637 /* Look in the type hash table for a type isomorphic to TYPE.
3638 If one is found, return it. Otherwise return 0. */
3641 type_hash_lookup (hashcode, type)
3645 register struct type_hash *h;
3646 for (h = type_hash_table[hashcode % TYPE_HASH_SIZE]; h; h = h->next)
3647 if (h->hashcode == hashcode
3648 && TREE_CODE (h->type) == TREE_CODE (type)
3649 && TREE_TYPE (h->type) == TREE_TYPE (type)
3650 && attribute_list_equal (TYPE_ATTRIBUTES (h->type),
3651 TYPE_ATTRIBUTES (type))
3652 && (TYPE_MAX_VALUE (h->type) == TYPE_MAX_VALUE (type)
3653 || tree_int_cst_equal (TYPE_MAX_VALUE (h->type),
3654 TYPE_MAX_VALUE (type)))
3655 && (TYPE_MIN_VALUE (h->type) == TYPE_MIN_VALUE (type)
3656 || tree_int_cst_equal (TYPE_MIN_VALUE (h->type),
3657 TYPE_MIN_VALUE (type)))
3658 /* Note that TYPE_DOMAIN is TYPE_ARG_TYPES for FUNCTION_TYPE. */
3659 && (TYPE_DOMAIN (h->type) == TYPE_DOMAIN (type)
3660 || (TYPE_DOMAIN (h->type)
3661 && TREE_CODE (TYPE_DOMAIN (h->type)) == TREE_LIST
3662 && TYPE_DOMAIN (type)
3663 && TREE_CODE (TYPE_DOMAIN (type)) == TREE_LIST
3664 && type_list_equal (TYPE_DOMAIN (h->type),
3665 TYPE_DOMAIN (type)))))
3670 /* Add an entry to the type-hash-table
3671 for a type TYPE whose hash code is HASHCODE. */
3674 type_hash_add (hashcode, type)
3678 register struct type_hash *h;
3680 h = (struct type_hash *) oballoc (sizeof (struct type_hash));
3681 h->hashcode = hashcode;
3683 h->next = type_hash_table[hashcode % TYPE_HASH_SIZE];
3684 type_hash_table[hashcode % TYPE_HASH_SIZE] = h;
3687 /* Given TYPE, and HASHCODE its hash code, return the canonical
3688 object for an identical type if one already exists.
3689 Otherwise, return TYPE, and record it as the canonical object
3690 if it is a permanent object.
3692 To use this function, first create a type of the sort you want.
3693 Then compute its hash code from the fields of the type that
3694 make it different from other similar types.
3695 Then call this function and use the value.
3696 This function frees the type you pass in if it is a duplicate. */
3698 /* Set to 1 to debug without canonicalization. Never set by program. */
3699 int debug_no_type_hash = 0;
3702 type_hash_canon (hashcode, type)
3708 if (debug_no_type_hash)
3711 t1 = type_hash_lookup (hashcode, type);
3714 obstack_free (TYPE_OBSTACK (type), type);
3715 #ifdef GATHER_STATISTICS
3716 tree_node_counts[(int)t_kind]--;
3717 tree_node_sizes[(int)t_kind] -= sizeof (struct tree_type);
3722 /* If this is a permanent type, record it for later reuse. */
3723 if (TREE_PERMANENT (type))
3724 type_hash_add (hashcode, type);
3729 /* Compute a hash code for a list of attributes (chain of TREE_LIST nodes
3730 with names in the TREE_PURPOSE slots and args in the TREE_VALUE slots),
3731 by adding the hash codes of the individual attributes. */
3734 attribute_hash_list (list)
3737 register int hashcode;
3739 for (hashcode = 0, tail = list; tail; tail = TREE_CHAIN (tail))
3740 /* ??? Do we want to add in TREE_VALUE too? */
3741 hashcode += TYPE_HASH (TREE_PURPOSE (tail));
3745 /* Given two lists of attributes, return true if list l2 is
3746 equivalent to l1. */
3749 attribute_list_equal (l1, l2)
3752 return attribute_list_contained (l1, l2)
3753 && attribute_list_contained (l2, l1);
3756 /* Given two lists of attributes, return true if list L2 is
3757 completely contained within L1. */
3758 /* ??? This would be faster if attribute names were stored in a canonicalized
3759 form. Otherwise, if L1 uses `foo' and L2 uses `__foo__', the long method
3760 must be used to show these elements are equivalent (which they are). */
3761 /* ??? It's not clear that attributes with arguments will always be handled
3765 attribute_list_contained (l1, l2)
3768 register tree t1, t2;
3770 /* First check the obvious, maybe the lists are identical. */
3774 /* Maybe the lists are similar. */
3775 for (t1 = l1, t2 = l2;
3777 && TREE_PURPOSE (t1) == TREE_PURPOSE (t2)
3778 && TREE_VALUE (t1) == TREE_VALUE (t2);
3779 t1 = TREE_CHAIN (t1), t2 = TREE_CHAIN (t2));
3781 /* Maybe the lists are equal. */
3782 if (t1 == 0 && t2 == 0)
3785 for (; t2; t2 = TREE_CHAIN (t2))
3788 = lookup_attribute (IDENTIFIER_POINTER (TREE_PURPOSE (t2)), l1);
3790 if (attr == NULL_TREE)
3792 if (simple_cst_equal (TREE_VALUE (t2), TREE_VALUE (attr)) != 1)
3799 /* Given two lists of types
3800 (chains of TREE_LIST nodes with types in the TREE_VALUE slots)
3801 return 1 if the lists contain the same types in the same order.
3802 Also, the TREE_PURPOSEs must match. */
3805 type_list_equal (l1, l2)
3808 register tree t1, t2;
3810 for (t1 = l1, t2 = l2; t1 && t2; t1 = TREE_CHAIN (t1), t2 = TREE_CHAIN (t2))
3811 if (TREE_VALUE (t1) != TREE_VALUE (t2)
3812 || (TREE_PURPOSE (t1) != TREE_PURPOSE (t2)
3813 && ! (1 == simple_cst_equal (TREE_PURPOSE (t1), TREE_PURPOSE (t2))
3814 && (TREE_TYPE (TREE_PURPOSE (t1))
3815 == TREE_TYPE (TREE_PURPOSE (t2))))))
3821 /* Nonzero if integer constants T1 and T2
3822 represent the same constant value. */
3825 tree_int_cst_equal (t1, t2)
3830 if (t1 == 0 || t2 == 0)
3832 if (TREE_CODE (t1) == INTEGER_CST
3833 && TREE_CODE (t2) == INTEGER_CST
3834 && TREE_INT_CST_LOW (t1) == TREE_INT_CST_LOW (t2)
3835 && TREE_INT_CST_HIGH (t1) == TREE_INT_CST_HIGH (t2))
3840 /* Nonzero if integer constants T1 and T2 represent values that satisfy <.
3841 The precise way of comparison depends on their data type. */
3844 tree_int_cst_lt (t1, t2)
3850 if (!TREE_UNSIGNED (TREE_TYPE (t1)))
3851 return INT_CST_LT (t1, t2);
3852 return INT_CST_LT_UNSIGNED (t1, t2);
3855 /* Return an indication of the sign of the integer constant T.
3856 The return value is -1 if T < 0, 0 if T == 0, and 1 if T > 0.
3857 Note that -1 will never be returned it T's type is unsigned. */
3860 tree_int_cst_sgn (t)
3863 if (TREE_INT_CST_LOW (t) == 0 && TREE_INT_CST_HIGH (t) == 0)
3865 else if (TREE_UNSIGNED (TREE_TYPE (t)))
3867 else if (TREE_INT_CST_HIGH (t) < 0)
3873 /* Compare two constructor-element-type constants. Return 1 if the lists
3874 are known to be equal; otherwise return 0. */
3877 simple_cst_list_equal (l1, l2)
3880 while (l1 != NULL_TREE && l2 != NULL_TREE)
3882 if (simple_cst_equal (TREE_VALUE (l1), TREE_VALUE (l2)) != 1)
3885 l1 = TREE_CHAIN (l1);
3886 l2 = TREE_CHAIN (l2);
3892 /* Return truthvalue of whether T1 is the same tree structure as T2.
3893 Return 1 if they are the same.
3894 Return 0 if they are understandably different.
3895 Return -1 if either contains tree structure not understood by
3899 simple_cst_equal (t1, t2)
3902 register enum tree_code code1, code2;
3907 if (t1 == 0 || t2 == 0)
3910 code1 = TREE_CODE (t1);
3911 code2 = TREE_CODE (t2);
3913 if (code1 == NOP_EXPR || code1 == CONVERT_EXPR || code1 == NON_LVALUE_EXPR)
3914 if (code2 == NOP_EXPR || code2 == CONVERT_EXPR || code2 == NON_LVALUE_EXPR)
3915 return simple_cst_equal (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0));
3917 return simple_cst_equal (TREE_OPERAND (t1, 0), t2);
3918 else if (code2 == NOP_EXPR || code2 == CONVERT_EXPR
3919 || code2 == NON_LVALUE_EXPR)
3920 return simple_cst_equal (t1, TREE_OPERAND (t2, 0));
3928 return TREE_INT_CST_LOW (t1) == TREE_INT_CST_LOW (t2)
3929 && TREE_INT_CST_HIGH (t1) == TREE_INT_CST_HIGH (t2);
3932 return REAL_VALUES_IDENTICAL (TREE_REAL_CST (t1), TREE_REAL_CST (t2));
3935 return TREE_STRING_LENGTH (t1) == TREE_STRING_LENGTH (t2)
3936 && !bcmp (TREE_STRING_POINTER (t1), TREE_STRING_POINTER (t2),
3937 TREE_STRING_LENGTH (t1));
3943 return simple_cst_equal (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0));
3946 cmp = simple_cst_equal (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0));
3949 return simple_cst_list_equal (TREE_OPERAND (t1, 1), TREE_OPERAND (t2, 1));
3952 /* Special case: if either target is an unallocated VAR_DECL,
3953 it means that it's going to be unified with whatever the
3954 TARGET_EXPR is really supposed to initialize, so treat it
3955 as being equivalent to anything. */
3956 if ((TREE_CODE (TREE_OPERAND (t1, 0)) == VAR_DECL
3957 && DECL_NAME (TREE_OPERAND (t1, 0)) == NULL_TREE
3958 && DECL_RTL (TREE_OPERAND (t1, 0)) == 0)
3959 || (TREE_CODE (TREE_OPERAND (t2, 0)) == VAR_DECL
3960 && DECL_NAME (TREE_OPERAND (t2, 0)) == NULL_TREE
3961 && DECL_RTL (TREE_OPERAND (t2, 0)) == 0))
3964 cmp = simple_cst_equal (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0));
3967 return simple_cst_equal (TREE_OPERAND (t1, 1), TREE_OPERAND (t2, 1));
3969 case WITH_CLEANUP_EXPR:
3970 cmp = simple_cst_equal (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0));
3973 return simple_cst_equal (TREE_OPERAND (t1, 2), TREE_OPERAND (t1, 2));
3976 if (TREE_OPERAND (t1, 1) == TREE_OPERAND (t2, 1))
3977 return simple_cst_equal (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0));
3990 /* This general rule works for most tree codes. All exceptions should be
3991 handled above. If this is a language-specific tree code, we can't
3992 trust what might be in the operand, so say we don't know
3994 if ((int) code1 >= (int) LAST_AND_UNUSED_TREE_CODE)
3997 switch (TREE_CODE_CLASS (code1))
4007 for (i=0; i<tree_code_length[(int) code1]; ++i)
4009 cmp = simple_cst_equal (TREE_OPERAND (t1, i), TREE_OPERAND (t2, i));
4020 /* Constructors for pointer, array and function types.
4021 (RECORD_TYPE, UNION_TYPE and ENUMERAL_TYPE nodes are
4022 constructed by language-dependent code, not here.) */
4024 /* Construct, lay out and return the type of pointers to TO_TYPE.
4025 If such a type has already been constructed, reuse it. */
4028 build_pointer_type (to_type)
4031 register tree t = TYPE_POINTER_TO (to_type);
4033 /* First, if we already have a type for pointers to TO_TYPE, use it. */
4038 /* We need a new one. Put this in the same obstack as TO_TYPE. */
4039 push_obstacks (TYPE_OBSTACK (to_type), TYPE_OBSTACK (to_type));
4040 t = make_node (POINTER_TYPE);
4043 TREE_TYPE (t) = to_type;
4045 /* Record this type as the pointer to TO_TYPE. */
4046 TYPE_POINTER_TO (to_type) = t;
4048 /* Lay out the type. This function has many callers that are concerned
4049 with expression-construction, and this simplifies them all.
4050 Also, it guarantees the TYPE_SIZE is in the same obstack as the type. */
4056 /* Create a type of integers to be the TYPE_DOMAIN of an ARRAY_TYPE.
4057 MAXVAL should be the maximum value in the domain
4058 (one less than the length of the array).
4060 The maximum value that MAXVAL can have is INT_MAX for a HOST_WIDE_INT.
4061 We don't enforce this limit, that is up to caller (e.g. language front end).
4062 The limit exists because the result is a signed type and we don't handle
4063 sizes that use more than one HOST_WIDE_INT. */
4066 build_index_type (maxval)
4069 register tree itype = make_node (INTEGER_TYPE);
4071 TYPE_PRECISION (itype) = TYPE_PRECISION (sizetype);
4072 TYPE_MIN_VALUE (itype) = size_zero_node;
4074 push_obstacks (TYPE_OBSTACK (itype), TYPE_OBSTACK (itype));
4075 TYPE_MAX_VALUE (itype) = convert (sizetype, maxval);
4078 TYPE_MODE (itype) = TYPE_MODE (sizetype);
4079 TYPE_SIZE (itype) = TYPE_SIZE (sizetype);
4080 TYPE_ALIGN (itype) = TYPE_ALIGN (sizetype);
4081 if (TREE_CODE (maxval) == INTEGER_CST)
4083 int maxint = (int) TREE_INT_CST_LOW (maxval);
4084 /* If the domain should be empty, make sure the maxval
4085 remains -1 and is not spoiled by truncation. */
4086 if (INT_CST_LT (maxval, integer_zero_node))
4088 TYPE_MAX_VALUE (itype) = build_int_2 (-1, -1);
4089 TREE_TYPE (TYPE_MAX_VALUE (itype)) = sizetype;
4091 return type_hash_canon (maxint < 0 ? ~maxint : maxint, itype);
4097 /* Create a range of some discrete type TYPE (an INTEGER_TYPE,
4098 ENUMERAL_TYPE, BOOLEAN_TYPE, or CHAR_TYPE), with
4099 low bound LOWVAL and high bound HIGHVAL.
4100 if TYPE==NULL_TREE, sizetype is used. */
4103 build_range_type (type, lowval, highval)
4104 tree type, lowval, highval;
4106 register tree itype = make_node (INTEGER_TYPE);
4108 TREE_TYPE (itype) = type;
4109 if (type == NULL_TREE)
4112 push_obstacks (TYPE_OBSTACK (itype), TYPE_OBSTACK (itype));
4113 TYPE_MIN_VALUE (itype) = convert (type, lowval);
4114 TYPE_MAX_VALUE (itype) = highval ? convert (type, highval) : NULL;
4117 TYPE_PRECISION (itype) = TYPE_PRECISION (type);
4118 TYPE_MODE (itype) = TYPE_MODE (type);
4119 TYPE_SIZE (itype) = TYPE_SIZE (type);
4120 TYPE_ALIGN (itype) = TYPE_ALIGN (type);
4121 if (TREE_CODE (lowval) == INTEGER_CST)
4123 HOST_WIDE_INT lowint, highint;
4126 lowint = TREE_INT_CST_LOW (lowval);
4127 if (highval && TREE_CODE (highval) == INTEGER_CST)
4128 highint = TREE_INT_CST_LOW (highval);
4130 highint = (~(unsigned HOST_WIDE_INT)0) >> 1;
4132 maxint = (int) (highint - lowint);
4133 return type_hash_canon (maxint < 0 ? ~maxint : maxint, itype);
4139 /* Just like build_index_type, but takes lowval and highval instead
4140 of just highval (maxval). */
4143 build_index_2_type (lowval,highval)
4144 tree lowval, highval;
4146 return build_range_type (NULL_TREE, lowval, highval);
4149 /* Return nonzero iff ITYPE1 and ITYPE2 are equal (in the LISP sense).
4150 Needed because when index types are not hashed, equal index types
4151 built at different times appear distinct, even though structurally,
4155 index_type_equal (itype1, itype2)
4156 tree itype1, itype2;
4158 if (TREE_CODE (itype1) != TREE_CODE (itype2))
4160 if (TREE_CODE (itype1) == INTEGER_TYPE)
4162 if (TYPE_PRECISION (itype1) != TYPE_PRECISION (itype2)
4163 || TYPE_MODE (itype1) != TYPE_MODE (itype2)
4164 || simple_cst_equal (TYPE_SIZE (itype1), TYPE_SIZE (itype2)) != 1
4165 || TYPE_ALIGN (itype1) != TYPE_ALIGN (itype2))
4167 if (1 == simple_cst_equal (TYPE_MIN_VALUE (itype1),
4168 TYPE_MIN_VALUE (itype2))
4169 && 1 == simple_cst_equal (TYPE_MAX_VALUE (itype1),
4170 TYPE_MAX_VALUE (itype2)))
4177 /* Construct, lay out and return the type of arrays of elements with ELT_TYPE
4178 and number of elements specified by the range of values of INDEX_TYPE.
4179 If such a type has already been constructed, reuse it. */
4182 build_array_type (elt_type, index_type)
4183 tree elt_type, index_type;
4188 if (TREE_CODE (elt_type) == FUNCTION_TYPE)
4190 error ("arrays of functions are not meaningful");
4191 elt_type = integer_type_node;
4194 /* Make sure TYPE_POINTER_TO (elt_type) is filled in. */
4195 build_pointer_type (elt_type);
4197 /* Allocate the array after the pointer type,
4198 in case we free it in type_hash_canon. */
4199 t = make_node (ARRAY_TYPE);
4200 TREE_TYPE (t) = elt_type;
4201 TYPE_DOMAIN (t) = index_type;
4203 if (index_type == 0)
4208 hashcode = TYPE_HASH (elt_type) + TYPE_HASH (index_type);
4209 t = type_hash_canon (hashcode, t);
4211 if (TYPE_SIZE (t) == 0)
4216 /* Construct, lay out and return
4217 the type of functions returning type VALUE_TYPE
4218 given arguments of types ARG_TYPES.
4219 ARG_TYPES is a chain of TREE_LIST nodes whose TREE_VALUEs
4220 are data type nodes for the arguments of the function.
4221 If such a type has already been constructed, reuse it. */
4224 build_function_type (value_type, arg_types)
4225 tree value_type, arg_types;
4230 if (TREE_CODE (value_type) == FUNCTION_TYPE)
4232 error ("function return type cannot be function");
4233 value_type = integer_type_node;
4236 /* Make a node of the sort we want. */
4237 t = make_node (FUNCTION_TYPE);
4238 TREE_TYPE (t) = value_type;
4239 TYPE_ARG_TYPES (t) = arg_types;
4241 /* If we already have such a type, use the old one and free this one. */
4242 hashcode = TYPE_HASH (value_type) + type_hash_list (arg_types);
4243 t = type_hash_canon (hashcode, t);
4245 if (TYPE_SIZE (t) == 0)
4250 /* Build the node for the type of references-to-TO_TYPE. */
4253 build_reference_type (to_type)
4256 register tree t = TYPE_REFERENCE_TO (to_type);
4258 /* First, if we already have a type for pointers to TO_TYPE, use it. */
4263 /* We need a new one. Put this in the same obstack as TO_TYPE. */
4264 push_obstacks (TYPE_OBSTACK (to_type), TYPE_OBSTACK (to_type));
4265 t = make_node (REFERENCE_TYPE);
4268 TREE_TYPE (t) = to_type;
4270 /* Record this type as the pointer to TO_TYPE. */
4271 TYPE_REFERENCE_TO (to_type) = t;
4278 /* Construct, lay out and return the type of methods belonging to class
4279 BASETYPE and whose arguments and values are described by TYPE.
4280 If that type exists already, reuse it.
4281 TYPE must be a FUNCTION_TYPE node. */
4284 build_method_type (basetype, type)
4285 tree basetype, type;
4290 /* Make a node of the sort we want. */
4291 t = make_node (METHOD_TYPE);
4293 if (TREE_CODE (type) != FUNCTION_TYPE)
4296 TYPE_METHOD_BASETYPE (t) = TYPE_MAIN_VARIANT (basetype);
4297 TREE_TYPE (t) = TREE_TYPE (type);
4299 /* The actual arglist for this function includes a "hidden" argument
4300 which is "this". Put it into the list of argument types. */
4303 = tree_cons (NULL_TREE,
4304 build_pointer_type (basetype), TYPE_ARG_TYPES (type));
4306 /* If we already have such a type, use the old one and free this one. */
4307 hashcode = TYPE_HASH (basetype) + TYPE_HASH (type);
4308 t = type_hash_canon (hashcode, t);
4310 if (TYPE_SIZE (t) == 0)
4316 /* Construct, lay out and return the type of offsets to a value
4317 of type TYPE, within an object of type BASETYPE.
4318 If a suitable offset type exists already, reuse it. */
4321 build_offset_type (basetype, type)
4322 tree basetype, type;
4327 /* Make a node of the sort we want. */
4328 t = make_node (OFFSET_TYPE);
4330 TYPE_OFFSET_BASETYPE (t) = TYPE_MAIN_VARIANT (basetype);
4331 TREE_TYPE (t) = type;
4333 /* If we already have such a type, use the old one and free this one. */
4334 hashcode = TYPE_HASH (basetype) + TYPE_HASH (type);
4335 t = type_hash_canon (hashcode, t);
4337 if (TYPE_SIZE (t) == 0)
4343 /* Create a complex type whose components are COMPONENT_TYPE. */
4346 build_complex_type (component_type)
4347 tree component_type;
4352 /* Make a node of the sort we want. */
4353 t = make_node (COMPLEX_TYPE);
4355 TREE_TYPE (t) = TYPE_MAIN_VARIANT (component_type);
4356 TYPE_VOLATILE (t) = TYPE_VOLATILE (component_type);
4357 TYPE_READONLY (t) = TYPE_READONLY (component_type);
4359 /* If we already have such a type, use the old one and free this one. */
4360 hashcode = TYPE_HASH (component_type);
4361 t = type_hash_canon (hashcode, t);
4363 if (TYPE_SIZE (t) == 0)
4369 /* Return OP, stripped of any conversions to wider types as much as is safe.
4370 Converting the value back to OP's type makes a value equivalent to OP.
4372 If FOR_TYPE is nonzero, we return a value which, if converted to
4373 type FOR_TYPE, would be equivalent to converting OP to type FOR_TYPE.
4375 If FOR_TYPE is nonzero, unaligned bit-field references may be changed to the
4376 narrowest type that can hold the value, even if they don't exactly fit.
4377 Otherwise, bit-field references are changed to a narrower type
4378 only if they can be fetched directly from memory in that type.
4380 OP must have integer, real or enumeral type. Pointers are not allowed!
4382 There are some cases where the obvious value we could return
4383 would regenerate to OP if converted to OP's type,
4384 but would not extend like OP to wider types.
4385 If FOR_TYPE indicates such extension is contemplated, we eschew such values.
4386 For example, if OP is (unsigned short)(signed char)-1,
4387 we avoid returning (signed char)-1 if FOR_TYPE is int,
4388 even though extending that to an unsigned short would regenerate OP,
4389 since the result of extending (signed char)-1 to (int)
4390 is different from (int) OP. */
4393 get_unwidened (op, for_type)
4397 /* Set UNS initially if converting OP to FOR_TYPE is a zero-extension. */
4398 /* TYPE_PRECISION is safe in place of type_precision since
4399 pointer types are not allowed. */
4400 register tree type = TREE_TYPE (op);
4401 register unsigned final_prec
4402 = TYPE_PRECISION (for_type != 0 ? for_type : type);
4404 = (for_type != 0 && for_type != type
4405 && final_prec > TYPE_PRECISION (type)
4406 && TREE_UNSIGNED (type));
4407 register tree win = op;
4409 while (TREE_CODE (op) == NOP_EXPR)
4411 register int bitschange
4412 = TYPE_PRECISION (TREE_TYPE (op))
4413 - TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (op, 0)));
4415 /* Truncations are many-one so cannot be removed.
4416 Unless we are later going to truncate down even farther. */
4418 && final_prec > TYPE_PRECISION (TREE_TYPE (op)))
4421 /* See what's inside this conversion. If we decide to strip it,
4423 op = TREE_OPERAND (op, 0);
4425 /* If we have not stripped any zero-extensions (uns is 0),
4426 we can strip any kind of extension.
4427 If we have previously stripped a zero-extension,
4428 only zero-extensions can safely be stripped.
4429 Any extension can be stripped if the bits it would produce
4430 are all going to be discarded later by truncating to FOR_TYPE. */
4434 if (! uns || final_prec <= TYPE_PRECISION (TREE_TYPE (op)))
4436 /* TREE_UNSIGNED says whether this is a zero-extension.
4437 Let's avoid computing it if it does not affect WIN
4438 and if UNS will not be needed again. */
4439 if ((uns || TREE_CODE (op) == NOP_EXPR)
4440 && TREE_UNSIGNED (TREE_TYPE (op)))
4448 if (TREE_CODE (op) == COMPONENT_REF
4449 /* Since type_for_size always gives an integer type. */
4450 && TREE_CODE (type) != REAL_TYPE
4451 /* Don't crash if field not laid out yet. */
4452 && DECL_SIZE (TREE_OPERAND (op, 1)) != 0)
4454 unsigned innerprec = TREE_INT_CST_LOW (DECL_SIZE (TREE_OPERAND (op, 1)));
4455 type = type_for_size (innerprec, TREE_UNSIGNED (TREE_OPERAND (op, 1)));
4457 /* We can get this structure field in the narrowest type it fits in.
4458 If FOR_TYPE is 0, do this only for a field that matches the
4459 narrower type exactly and is aligned for it
4460 The resulting extension to its nominal type (a fullword type)
4461 must fit the same conditions as for other extensions. */
4463 if (innerprec < TYPE_PRECISION (TREE_TYPE (op))
4464 && (for_type || ! DECL_BIT_FIELD (TREE_OPERAND (op, 1)))
4465 && (! uns || final_prec <= innerprec
4466 || TREE_UNSIGNED (TREE_OPERAND (op, 1)))
4469 win = build (COMPONENT_REF, type, TREE_OPERAND (op, 0),
4470 TREE_OPERAND (op, 1));
4471 TREE_SIDE_EFFECTS (win) = TREE_SIDE_EFFECTS (op);
4472 TREE_THIS_VOLATILE (win) = TREE_THIS_VOLATILE (op);
4473 TREE_RAISES (win) = TREE_RAISES (op);
4479 /* Return OP or a simpler expression for a narrower value
4480 which can be sign-extended or zero-extended to give back OP.
4481 Store in *UNSIGNEDP_PTR either 1 if the value should be zero-extended
4482 or 0 if the value should be sign-extended. */
4485 get_narrower (op, unsignedp_ptr)
4489 register int uns = 0;
4491 register tree win = op;
4493 while (TREE_CODE (op) == NOP_EXPR)
4495 register int bitschange
4496 = TYPE_PRECISION (TREE_TYPE (op))
4497 - TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (op, 0)));
4499 /* Truncations are many-one so cannot be removed. */
4503 /* See what's inside this conversion. If we decide to strip it,
4505 op = TREE_OPERAND (op, 0);
4509 /* An extension: the outermost one can be stripped,
4510 but remember whether it is zero or sign extension. */
4512 uns = TREE_UNSIGNED (TREE_TYPE (op));
4513 /* Otherwise, if a sign extension has been stripped,
4514 only sign extensions can now be stripped;
4515 if a zero extension has been stripped, only zero-extensions. */
4516 else if (uns != TREE_UNSIGNED (TREE_TYPE (op)))
4520 else /* bitschange == 0 */
4522 /* A change in nominal type can always be stripped, but we must
4523 preserve the unsignedness. */
4525 uns = TREE_UNSIGNED (TREE_TYPE (op));
4532 if (TREE_CODE (op) == COMPONENT_REF
4533 /* Since type_for_size always gives an integer type. */
4534 && TREE_CODE (TREE_TYPE (op)) != REAL_TYPE)
4536 unsigned innerprec = TREE_INT_CST_LOW (DECL_SIZE (TREE_OPERAND (op, 1)));
4537 tree type = type_for_size (innerprec, TREE_UNSIGNED (op));
4539 /* We can get this structure field in a narrower type that fits it,
4540 but the resulting extension to its nominal type (a fullword type)
4541 must satisfy the same conditions as for other extensions.
4543 Do this only for fields that are aligned (not bit-fields),
4544 because when bit-field insns will be used there is no
4545 advantage in doing this. */
4547 if (innerprec < TYPE_PRECISION (TREE_TYPE (op))
4548 && ! DECL_BIT_FIELD (TREE_OPERAND (op, 1))
4549 && (first || uns == TREE_UNSIGNED (TREE_OPERAND (op, 1)))
4553 uns = TREE_UNSIGNED (TREE_OPERAND (op, 1));
4554 win = build (COMPONENT_REF, type, TREE_OPERAND (op, 0),
4555 TREE_OPERAND (op, 1));
4556 TREE_SIDE_EFFECTS (win) = TREE_SIDE_EFFECTS (op);
4557 TREE_THIS_VOLATILE (win) = TREE_THIS_VOLATILE (op);
4558 TREE_RAISES (win) = TREE_RAISES (op);
4561 *unsignedp_ptr = uns;
4565 /* Return the precision of a type, for arithmetic purposes.
4566 Supports all types on which arithmetic is possible
4567 (including pointer types).
4568 It's not clear yet what will be right for complex types. */
4571 type_precision (type)
4574 return ((TREE_CODE (type) == INTEGER_TYPE
4575 || TREE_CODE (type) == ENUMERAL_TYPE
4576 || TREE_CODE (type) == REAL_TYPE)
4577 ? TYPE_PRECISION (type) : POINTER_SIZE);
4580 /* Nonzero if integer constant C has a value that is permissible
4581 for type TYPE (an INTEGER_TYPE). */
4584 int_fits_type_p (c, type)
4587 if (TREE_UNSIGNED (type))
4588 return (! (TREE_CODE (TYPE_MAX_VALUE (type)) == INTEGER_CST
4589 && INT_CST_LT_UNSIGNED (TYPE_MAX_VALUE (type), c))
4590 && ! (TREE_CODE (TYPE_MIN_VALUE (type)) == INTEGER_CST
4591 && INT_CST_LT_UNSIGNED (c, TYPE_MIN_VALUE (type)))
4592 /* Negative ints never fit unsigned types. */
4593 && ! (TREE_INT_CST_HIGH (c) < 0
4594 && ! TREE_UNSIGNED (TREE_TYPE (c))));
4596 return (! (TREE_CODE (TYPE_MAX_VALUE (type)) == INTEGER_CST
4597 && INT_CST_LT (TYPE_MAX_VALUE (type), c))
4598 && ! (TREE_CODE (TYPE_MIN_VALUE (type)) == INTEGER_CST
4599 && INT_CST_LT (c, TYPE_MIN_VALUE (type)))
4600 /* Unsigned ints with top bit set never fit signed types. */
4601 && ! (TREE_INT_CST_HIGH (c) < 0
4602 && TREE_UNSIGNED (TREE_TYPE (c))));
4605 /* Return the innermost context enclosing DECL that is
4606 a FUNCTION_DECL, or zero if none. */
4609 decl_function_context (decl)
4614 if (TREE_CODE (decl) == ERROR_MARK)
4617 if (TREE_CODE (decl) == SAVE_EXPR)
4618 context = SAVE_EXPR_CONTEXT (decl);
4620 context = DECL_CONTEXT (decl);
4622 while (context && TREE_CODE (context) != FUNCTION_DECL)
4624 if (TREE_CODE (context) == RECORD_TYPE
4625 || TREE_CODE (context) == UNION_TYPE
4626 || TREE_CODE (context) == QUAL_UNION_TYPE)
4627 context = TYPE_CONTEXT (context);
4628 else if (TREE_CODE (context) == TYPE_DECL)
4629 context = DECL_CONTEXT (context);
4630 else if (TREE_CODE (context) == BLOCK)
4631 context = BLOCK_SUPERCONTEXT (context);
4633 /* Unhandled CONTEXT !? */
4640 /* Return the innermost context enclosing DECL that is
4641 a RECORD_TYPE, UNION_TYPE or QUAL_UNION_TYPE, or zero if none.
4642 TYPE_DECLs and FUNCTION_DECLs are transparent to this function. */
4645 decl_type_context (decl)
4648 tree context = DECL_CONTEXT (decl);
4652 if (TREE_CODE (context) == RECORD_TYPE
4653 || TREE_CODE (context) == UNION_TYPE
4654 || TREE_CODE (context) == QUAL_UNION_TYPE)
4656 if (TREE_CODE (context) == TYPE_DECL
4657 || TREE_CODE (context) == FUNCTION_DECL)
4658 context = DECL_CONTEXT (context);
4659 else if (TREE_CODE (context) == BLOCK)
4660 context = BLOCK_SUPERCONTEXT (context);
4662 /* Unhandled CONTEXT!? */
4668 /* Print debugging information about the size of the
4669 toplev_inline_obstacks. */
4672 print_inline_obstack_statistics ()
4674 struct simple_obstack_stack *current = toplev_inline_obstacks;
4679 for (; current; current = current->next, ++n_obstacks)
4681 struct obstack *o = current->obstack;
4682 struct _obstack_chunk *chunk = o->chunk;
4684 n_alloc += o->next_free - chunk->contents;
4685 chunk = chunk->prev;
4687 for (; chunk; chunk = chunk->prev, ++n_chunks)
4688 n_alloc += chunk->limit - &chunk->contents[0];
4690 fprintf (stderr, "inline obstacks: %d obstacks, %d bytes, %d chunks\n",
4691 n_obstacks, n_alloc, n_chunks);
4694 /* Print debugging information about the obstack O, named STR. */
4697 print_obstack_statistics (str, o)
4701 struct _obstack_chunk *chunk = o->chunk;
4705 n_alloc += o->next_free - chunk->contents;
4706 chunk = chunk->prev;
4710 n_alloc += chunk->limit - &chunk->contents[0];
4711 chunk = chunk->prev;
4713 fprintf (stderr, "obstack %s: %u bytes, %d chunks\n",
4714 str, n_alloc, n_chunks);
4717 /* Print debugging information about tree nodes generated during the compile,
4718 and any language-specific information. */
4721 dump_tree_statistics ()
4723 #ifdef GATHER_STATISTICS
4725 int total_nodes, total_bytes;
4728 fprintf (stderr, "\n??? tree nodes created\n\n");
4729 #ifdef GATHER_STATISTICS
4730 fprintf (stderr, "Kind Nodes Bytes\n");
4731 fprintf (stderr, "-------------------------------------\n");
4732 total_nodes = total_bytes = 0;
4733 for (i = 0; i < (int) all_kinds; i++)
4735 fprintf (stderr, "%-20s %6d %9d\n", tree_node_kind_names[i],
4736 tree_node_counts[i], tree_node_sizes[i]);
4737 total_nodes += tree_node_counts[i];
4738 total_bytes += tree_node_sizes[i];
4740 fprintf (stderr, "%-20s %9d\n", "identifier names", id_string_size);
4741 fprintf (stderr, "-------------------------------------\n");
4742 fprintf (stderr, "%-20s %6d %9d\n", "Total", total_nodes, total_bytes);
4743 fprintf (stderr, "-------------------------------------\n");
4745 fprintf (stderr, "(No per-node statistics)\n");
4747 print_obstack_statistics ("permanent_obstack", &permanent_obstack);
4748 print_obstack_statistics ("maybepermanent_obstack", &maybepermanent_obstack);
4749 print_obstack_statistics ("temporary_obstack", &temporary_obstack);
4750 print_obstack_statistics ("momentary_obstack", &momentary_obstack);
4751 print_obstack_statistics ("temp_decl_obstack", &temp_decl_obstack);
4752 print_inline_obstack_statistics ();
4753 print_lang_statistics ();
4756 #define FILE_FUNCTION_PREFIX_LEN 9
4758 #ifndef NO_DOLLAR_IN_LABEL
4759 #define FILE_FUNCTION_FORMAT "_GLOBAL_$D$%s"
4760 #else /* NO_DOLLAR_IN_LABEL */
4761 #ifndef NO_DOT_IN_LABEL
4762 #define FILE_FUNCTION_FORMAT "_GLOBAL_.D.%s"
4763 #else /* NO_DOT_IN_LABEL */
4764 #define FILE_FUNCTION_FORMAT "_GLOBAL__D_%s"
4765 #endif /* NO_DOT_IN_LABEL */
4766 #endif /* NO_DOLLAR_IN_LABEL */
4768 extern char * first_global_object_name;
4770 /* If KIND=='I', return a suitable global initializer (constructor) name.
4771 If KIND=='D', return a suitable global clean-up (destructor) name. */
4774 get_file_function_name (kind)
4780 if (first_global_object_name)
4781 p = first_global_object_name;
4782 else if (main_input_filename)
4783 p = main_input_filename;
4787 buf = (char *) alloca (sizeof (FILE_FUNCTION_FORMAT) + strlen (p));
4789 /* Set up the name of the file-level functions we may need. */
4790 /* Use a global object (which is already required to be unique over
4791 the program) rather than the file name (which imposes extra
4792 constraints). -- Raeburn@MIT.EDU, 10 Jan 1990. */
4793 sprintf (buf, FILE_FUNCTION_FORMAT, p);
4795 /* Don't need to pull weird characters out of global names. */
4796 if (p != first_global_object_name)
4798 for (p = buf+11; *p; p++)
4799 if (! ((*p >= '0' && *p <= '9')
4800 #if 0 /* we always want labels, which are valid C++ identifiers (+ `$') */
4801 #ifndef ASM_IDENTIFY_GCC /* this is required if `.' is invalid -- k. raeburn */
4805 #ifndef NO_DOLLAR_IN_LABEL /* this for `$'; unlikely, but... -- kr */
4808 #ifndef NO_DOT_IN_LABEL /* this for `.'; unlikely, but... */
4811 || (*p >= 'A' && *p <= 'Z')
4812 || (*p >= 'a' && *p <= 'z')))
4816 buf[FILE_FUNCTION_PREFIX_LEN] = kind;
4818 return get_identifier (buf);
4821 /* Expand (the constant part of) a SET_TYPE CONSTRUCTOR node.
4822 The result is placed in BUFFER (which has length BIT_SIZE),
4823 with one bit in each char ('\000' or '\001').
4825 If the constructor is constant, NULL_TREE is returned.
4826 Otherwise, a TREE_LIST of the non-constant elements is emitted. */
4829 get_set_constructor_bits (init, buffer, bit_size)
4836 HOST_WIDE_INT domain_min
4837 = TREE_INT_CST_LOW (TYPE_MIN_VALUE (TYPE_DOMAIN (TREE_TYPE (init))));
4838 tree non_const_bits = NULL_TREE;
4839 for (i = 0; i < bit_size; i++)
4842 for (vals = TREE_OPERAND (init, 1);
4843 vals != NULL_TREE; vals = TREE_CHAIN (vals))
4845 if (TREE_CODE (TREE_VALUE (vals)) != INTEGER_CST
4846 || (TREE_PURPOSE (vals) != NULL_TREE
4847 && TREE_CODE (TREE_PURPOSE (vals)) != INTEGER_CST))
4849 = tree_cons (TREE_PURPOSE (vals), TREE_VALUE (vals), non_const_bits);
4850 else if (TREE_PURPOSE (vals) != NULL_TREE)
4852 /* Set a range of bits to ones. */
4853 HOST_WIDE_INT lo_index
4854 = TREE_INT_CST_LOW (TREE_PURPOSE (vals)) - domain_min;
4855 HOST_WIDE_INT hi_index
4856 = TREE_INT_CST_LOW (TREE_VALUE (vals)) - domain_min;
4857 if (lo_index < 0 || lo_index >= bit_size
4858 || hi_index < 0 || hi_index >= bit_size)
4860 for ( ; lo_index <= hi_index; lo_index++)
4861 buffer[lo_index] = 1;
4865 /* Set a single bit to one. */
4867 = TREE_INT_CST_LOW (TREE_VALUE (vals)) - domain_min;
4868 if (index < 0 || index >= bit_size)
4870 error ("invalid initializer for bit string");
4876 return non_const_bits;
4879 /* Expand (the constant part of) a SET_TYPE CONSTRUCTOR node.
4880 The result is placed in BUFFER (which is an array of bytes).
4881 If the constructor is constant, NULL_TREE is returned.
4882 Otherwise, a TREE_LIST of the non-constant elements is emitted. */
4885 get_set_constructor_bytes (init, buffer, wd_size)
4887 unsigned char *buffer;
4891 int set_word_size = BITS_PER_UNIT;
4892 int bit_size = wd_size * set_word_size;
4894 unsigned char *bytep = buffer;
4895 char *bit_buffer = (char *) alloca(bit_size);
4896 tree non_const_bits = get_set_constructor_bits (init, bit_buffer, bit_size);
4898 for (i = 0; i < wd_size; i++)
4901 for (i = 0; i < bit_size; i++)
4905 if (BYTES_BIG_ENDIAN)
4906 *bytep |= (1 << (set_word_size - 1 - bit_pos));
4908 *bytep |= 1 << bit_pos;
4911 if (bit_pos >= set_word_size)
4912 bit_pos = 0, bytep++;
4914 return non_const_bits;