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];
1188 /* EXPR_WITH_FILE_LOCATION must keep filename info stored in TREE_CHAIN */
1189 if (TREE_CODE (node) != EXPR_WITH_FILE_LOCATION)
1191 TREE_ASM_WRITTEN (t) = 0;
1193 if (TREE_CODE_CLASS (code) == 'd')
1194 DECL_UID (t) = next_decl_uid++;
1195 else if (TREE_CODE_CLASS (code) == 't')
1197 TYPE_UID (t) = next_type_uid++;
1198 TYPE_OBSTACK (t) = current_obstack;
1200 /* The following is so that the debug code for
1201 the copy is different from the original type.
1202 The two statements usually duplicate each other
1203 (because they clear fields of the same union),
1204 but the optimizer should catch that. */
1205 TYPE_SYMTAB_POINTER (t) = 0;
1206 TYPE_SYMTAB_ADDRESS (t) = 0;
1209 TREE_PERMANENT (t) = (current_obstack == &permanent_obstack);
1214 /* Return a copy of a chain of nodes, chained through the TREE_CHAIN field.
1215 For example, this can copy a list made of TREE_LIST nodes. */
1222 register tree prev, next;
1227 head = prev = copy_node (list);
1228 next = TREE_CHAIN (list);
1231 TREE_CHAIN (prev) = copy_node (next);
1232 prev = TREE_CHAIN (prev);
1233 next = TREE_CHAIN (next);
1240 /* Return an IDENTIFIER_NODE whose name is TEXT (a null-terminated string).
1241 If an identifier with that name has previously been referred to,
1242 the same node is returned this time. */
1245 get_identifier (text)
1246 register char *text;
1251 register int len, hash_len;
1253 /* Compute length of text in len. */
1254 for (len = 0; text[len]; len++);
1256 /* Decide how much of that length to hash on */
1258 if (warn_id_clash && len > id_clash_len)
1259 hash_len = id_clash_len;
1261 /* Compute hash code */
1262 hi = hash_len * 613 + (unsigned) text[0];
1263 for (i = 1; i < hash_len; i += 2)
1264 hi = ((hi * 613) + (unsigned) (text[i]));
1266 hi &= (1 << HASHBITS) - 1;
1267 hi %= MAX_HASH_TABLE;
1269 /* Search table for identifier */
1270 for (idp = hash_table[hi]; idp; idp = TREE_CHAIN (idp))
1271 if (IDENTIFIER_LENGTH (idp) == len
1272 && IDENTIFIER_POINTER (idp)[0] == text[0]
1273 && !bcmp (IDENTIFIER_POINTER (idp), text, len))
1274 return idp; /* <-- return if found */
1276 /* Not found; optionally warn about a similar identifier */
1277 if (warn_id_clash && do_identifier_warnings && len >= id_clash_len)
1278 for (idp = hash_table[hi]; idp; idp = TREE_CHAIN (idp))
1279 if (!strncmp (IDENTIFIER_POINTER (idp), text, id_clash_len))
1281 warning ("`%s' and `%s' identical in first %d characters",
1282 IDENTIFIER_POINTER (idp), text, id_clash_len);
1286 if (tree_code_length[(int) IDENTIFIER_NODE] < 0)
1287 abort (); /* set_identifier_size hasn't been called. */
1289 /* Not found, create one, add to chain */
1290 idp = make_node (IDENTIFIER_NODE);
1291 IDENTIFIER_LENGTH (idp) = len;
1292 #ifdef GATHER_STATISTICS
1293 id_string_size += len;
1296 IDENTIFIER_POINTER (idp) = obstack_copy0 (&permanent_obstack, text, len);
1298 TREE_CHAIN (idp) = hash_table[hi];
1299 hash_table[hi] = idp;
1300 return idp; /* <-- return if created */
1303 /* If an identifier with the name TEXT (a null-terminated string) has
1304 previously been referred to, return that node; otherwise return
1308 maybe_get_identifier (text)
1309 register char *text;
1314 register int len, hash_len;
1316 /* Compute length of text in len. */
1317 for (len = 0; text[len]; len++);
1319 /* Decide how much of that length to hash on */
1321 if (warn_id_clash && len > id_clash_len)
1322 hash_len = id_clash_len;
1324 /* Compute hash code */
1325 hi = hash_len * 613 + (unsigned) text[0];
1326 for (i = 1; i < hash_len; i += 2)
1327 hi = ((hi * 613) + (unsigned) (text[i]));
1329 hi &= (1 << HASHBITS) - 1;
1330 hi %= MAX_HASH_TABLE;
1332 /* Search table for identifier */
1333 for (idp = hash_table[hi]; idp; idp = TREE_CHAIN (idp))
1334 if (IDENTIFIER_LENGTH (idp) == len
1335 && IDENTIFIER_POINTER (idp)[0] == text[0]
1336 && !bcmp (IDENTIFIER_POINTER (idp), text, len))
1337 return idp; /* <-- return if found */
1342 /* Enable warnings on similar identifiers (if requested).
1343 Done after the built-in identifiers are created. */
1346 start_identifier_warnings ()
1348 do_identifier_warnings = 1;
1351 /* Record the size of an identifier node for the language in use.
1352 SIZE is the total size in bytes.
1353 This is called by the language-specific files. This must be
1354 called before allocating any identifiers. */
1357 set_identifier_size (size)
1360 tree_code_length[(int) IDENTIFIER_NODE]
1361 = (size - sizeof (struct tree_common)) / sizeof (tree);
1364 /* Return a newly constructed INTEGER_CST node whose constant value
1365 is specified by the two ints LOW and HI.
1366 The TREE_TYPE is set to `int'.
1368 This function should be used via the `build_int_2' macro. */
1371 build_int_2_wide (low, hi)
1372 HOST_WIDE_INT low, hi;
1374 register tree t = make_node (INTEGER_CST);
1375 TREE_INT_CST_LOW (t) = low;
1376 TREE_INT_CST_HIGH (t) = hi;
1377 TREE_TYPE (t) = integer_type_node;
1381 /* Return a new REAL_CST node whose type is TYPE and value is D. */
1384 build_real (type, d)
1391 /* Check for valid float value for this type on this target machine;
1392 if not, can print error message and store a valid value in D. */
1393 #ifdef CHECK_FLOAT_VALUE
1394 CHECK_FLOAT_VALUE (TYPE_MODE (type), d, overflow);
1397 v = make_node (REAL_CST);
1398 TREE_TYPE (v) = type;
1399 TREE_REAL_CST (v) = d;
1400 TREE_OVERFLOW (v) = TREE_CONSTANT_OVERFLOW (v) = overflow;
1404 /* Return a new REAL_CST node whose type is TYPE
1405 and whose value is the integer value of the INTEGER_CST node I. */
1407 #if !defined (REAL_IS_NOT_DOUBLE) || defined (REAL_ARITHMETIC)
1410 real_value_from_int_cst (type, i)
1415 #ifdef REAL_ARITHMETIC
1416 if (! TREE_UNSIGNED (TREE_TYPE (i)))
1417 REAL_VALUE_FROM_INT (d, TREE_INT_CST_LOW (i), TREE_INT_CST_HIGH (i),
1420 REAL_VALUE_FROM_UNSIGNED_INT (d, TREE_INT_CST_LOW (i),
1421 TREE_INT_CST_HIGH (i), TYPE_MODE (type));
1422 #else /* not REAL_ARITHMETIC */
1423 /* Some 386 compilers mishandle unsigned int to float conversions,
1424 so introduce a temporary variable E to avoid those bugs. */
1425 if (TREE_INT_CST_HIGH (i) < 0 && ! TREE_UNSIGNED (TREE_TYPE (i)))
1429 d = (double) (~ TREE_INT_CST_HIGH (i));
1430 e = ((double) ((HOST_WIDE_INT) 1 << (HOST_BITS_PER_WIDE_INT / 2))
1431 * (double) ((HOST_WIDE_INT) 1 << (HOST_BITS_PER_WIDE_INT / 2)));
1433 e = (double) (unsigned HOST_WIDE_INT) (~ TREE_INT_CST_LOW (i));
1441 d = (double) (unsigned HOST_WIDE_INT) TREE_INT_CST_HIGH (i);
1442 e = ((double) ((HOST_WIDE_INT) 1 << (HOST_BITS_PER_WIDE_INT / 2))
1443 * (double) ((HOST_WIDE_INT) 1 << (HOST_BITS_PER_WIDE_INT / 2)));
1445 e = (double) (unsigned HOST_WIDE_INT) TREE_INT_CST_LOW (i);
1448 #endif /* not REAL_ARITHMETIC */
1452 /* This function can't be implemented if we can't do arithmetic
1453 on the float representation. */
1456 build_real_from_int_cst (type, i)
1461 int overflow = TREE_OVERFLOW (i);
1463 jmp_buf float_error;
1465 v = make_node (REAL_CST);
1466 TREE_TYPE (v) = type;
1468 if (setjmp (float_error))
1475 set_float_handler (float_error);
1477 #ifdef REAL_ARITHMETIC
1478 d = real_value_from_int_cst (type, i);
1480 d = REAL_VALUE_TRUNCATE (TYPE_MODE (type),
1481 real_value_from_int_cst (type, i));
1484 /* Check for valid float value for this type on this target machine. */
1487 set_float_handler (NULL_PTR);
1489 #ifdef CHECK_FLOAT_VALUE
1490 CHECK_FLOAT_VALUE (TYPE_MODE (type), d, overflow);
1493 TREE_REAL_CST (v) = d;
1494 TREE_OVERFLOW (v) = TREE_CONSTANT_OVERFLOW (v) = overflow;
1498 #endif /* not REAL_IS_NOT_DOUBLE, or REAL_ARITHMETIC */
1500 /* Return a newly constructed STRING_CST node whose value is
1501 the LEN characters at STR.
1502 The TREE_TYPE is not initialized. */
1505 build_string (len, str)
1509 /* Put the string in saveable_obstack since it will be placed in the RTL
1510 for an "asm" statement and will also be kept around a while if
1511 deferring constant output in varasm.c. */
1513 register tree s = make_node (STRING_CST);
1514 TREE_STRING_LENGTH (s) = len;
1515 TREE_STRING_POINTER (s) = obstack_copy0 (saveable_obstack, str, len);
1519 /* Return a newly constructed COMPLEX_CST node whose value is
1520 specified by the real and imaginary parts REAL and IMAG.
1521 Both REAL and IMAG should be constant nodes. TYPE, if specified,
1522 will be the type of the COMPLEX_CST; otherwise a new type will be made. */
1525 build_complex (type, real, imag)
1529 register tree t = make_node (COMPLEX_CST);
1531 TREE_REALPART (t) = real;
1532 TREE_IMAGPART (t) = imag;
1533 TREE_TYPE (t) = type ? type : build_complex_type (TREE_TYPE (real));
1534 TREE_OVERFLOW (t) = TREE_OVERFLOW (real) | TREE_OVERFLOW (imag);
1535 TREE_CONSTANT_OVERFLOW (t)
1536 = TREE_CONSTANT_OVERFLOW (real) | TREE_CONSTANT_OVERFLOW (imag);
1540 /* Build a newly constructed TREE_VEC node of length LEN. */
1547 register int length = (len-1) * sizeof (tree) + sizeof (struct tree_vec);
1548 register struct obstack *obstack = current_obstack;
1551 #ifdef GATHER_STATISTICS
1552 tree_node_counts[(int)vec_kind]++;
1553 tree_node_sizes[(int)vec_kind] += length;
1556 t = (tree) obstack_alloc (obstack, length);
1558 for (i = (length / sizeof (int)) - 1; i >= 0; i--)
1561 TREE_SET_CODE (t, TREE_VEC);
1562 TREE_VEC_LENGTH (t) = len;
1563 if (obstack == &permanent_obstack)
1564 TREE_PERMANENT (t) = 1;
1569 /* Return 1 if EXPR is the integer constant zero or a complex constant
1573 integer_zerop (expr)
1578 return ((TREE_CODE (expr) == INTEGER_CST
1579 && ! TREE_CONSTANT_OVERFLOW (expr)
1580 && TREE_INT_CST_LOW (expr) == 0
1581 && TREE_INT_CST_HIGH (expr) == 0)
1582 || (TREE_CODE (expr) == COMPLEX_CST
1583 && integer_zerop (TREE_REALPART (expr))
1584 && integer_zerop (TREE_IMAGPART (expr))));
1587 /* Return 1 if EXPR is the integer constant one or the corresponding
1588 complex constant. */
1596 return ((TREE_CODE (expr) == INTEGER_CST
1597 && ! TREE_CONSTANT_OVERFLOW (expr)
1598 && TREE_INT_CST_LOW (expr) == 1
1599 && TREE_INT_CST_HIGH (expr) == 0)
1600 || (TREE_CODE (expr) == COMPLEX_CST
1601 && integer_onep (TREE_REALPART (expr))
1602 && integer_zerop (TREE_IMAGPART (expr))));
1605 /* Return 1 if EXPR is an integer containing all 1's in as much precision as
1606 it contains. Likewise for the corresponding complex constant. */
1609 integer_all_onesp (expr)
1617 if (TREE_CODE (expr) == COMPLEX_CST
1618 && integer_all_onesp (TREE_REALPART (expr))
1619 && integer_zerop (TREE_IMAGPART (expr)))
1622 else if (TREE_CODE (expr) != INTEGER_CST
1623 || TREE_CONSTANT_OVERFLOW (expr))
1626 uns = TREE_UNSIGNED (TREE_TYPE (expr));
1628 return TREE_INT_CST_LOW (expr) == -1 && TREE_INT_CST_HIGH (expr) == -1;
1630 /* Note that using TYPE_PRECISION here is wrong. We care about the
1631 actual bits, not the (arbitrary) range of the type. */
1632 prec = GET_MODE_BITSIZE (TYPE_MODE (TREE_TYPE (expr)));
1633 if (prec >= HOST_BITS_PER_WIDE_INT)
1635 int high_value, shift_amount;
1637 shift_amount = prec - HOST_BITS_PER_WIDE_INT;
1639 if (shift_amount > HOST_BITS_PER_WIDE_INT)
1640 /* Can not handle precisions greater than twice the host int size. */
1642 else if (shift_amount == HOST_BITS_PER_WIDE_INT)
1643 /* Shifting by the host word size is undefined according to the ANSI
1644 standard, so we must handle this as a special case. */
1647 high_value = ((HOST_WIDE_INT) 1 << shift_amount) - 1;
1649 return TREE_INT_CST_LOW (expr) == -1
1650 && TREE_INT_CST_HIGH (expr) == high_value;
1653 return TREE_INT_CST_LOW (expr) == ((HOST_WIDE_INT) 1 << prec) - 1;
1656 /* Return 1 if EXPR is an integer constant that is a power of 2 (i.e., has only
1660 integer_pow2p (expr)
1664 HOST_WIDE_INT high, low;
1668 if (TREE_CODE (expr) == COMPLEX_CST
1669 && integer_pow2p (TREE_REALPART (expr))
1670 && integer_zerop (TREE_IMAGPART (expr)))
1673 if (TREE_CODE (expr) != INTEGER_CST || TREE_CONSTANT_OVERFLOW (expr))
1676 prec = (POINTER_TYPE_P (TREE_TYPE (expr))
1677 ? POINTER_SIZE : TYPE_PRECISION (TREE_TYPE (expr)));
1678 high = TREE_INT_CST_HIGH (expr);
1679 low = TREE_INT_CST_LOW (expr);
1681 /* First clear all bits that are beyond the type's precision in case
1682 we've been sign extended. */
1684 if (prec == 2 * HOST_BITS_PER_WIDE_INT)
1686 else if (prec > HOST_BITS_PER_WIDE_INT)
1687 high &= ~((HOST_WIDE_INT) (-1) << (prec - HOST_BITS_PER_WIDE_INT));
1691 if (prec < HOST_BITS_PER_WIDE_INT)
1692 low &= ~((HOST_WIDE_INT) (-1) << prec);
1695 if (high == 0 && low == 0)
1698 return ((high == 0 && (low & (low - 1)) == 0)
1699 || (low == 0 && (high & (high - 1)) == 0));
1702 /* Return the power of two represented by a tree node known to be a
1710 HOST_WIDE_INT high, low;
1714 if (TREE_CODE (expr) == COMPLEX_CST)
1715 return tree_log2 (TREE_REALPART (expr));
1717 prec = (POINTER_TYPE_P (TREE_TYPE (expr))
1718 ? POINTER_SIZE : TYPE_PRECISION (TREE_TYPE (expr)));
1720 high = TREE_INT_CST_HIGH (expr);
1721 low = TREE_INT_CST_LOW (expr);
1723 /* First clear all bits that are beyond the type's precision in case
1724 we've been sign extended. */
1726 if (prec == 2 * HOST_BITS_PER_WIDE_INT)
1728 else if (prec > HOST_BITS_PER_WIDE_INT)
1729 high &= ~((HOST_WIDE_INT) (-1) << (prec - HOST_BITS_PER_WIDE_INT));
1733 if (prec < HOST_BITS_PER_WIDE_INT)
1734 low &= ~((HOST_WIDE_INT) (-1) << prec);
1737 return (high != 0 ? HOST_BITS_PER_WIDE_INT + exact_log2 (high)
1738 : exact_log2 (low));
1741 /* Return 1 if EXPR is the real constant zero. */
1749 return ((TREE_CODE (expr) == REAL_CST
1750 && ! TREE_CONSTANT_OVERFLOW (expr)
1751 && REAL_VALUES_EQUAL (TREE_REAL_CST (expr), dconst0))
1752 || (TREE_CODE (expr) == COMPLEX_CST
1753 && real_zerop (TREE_REALPART (expr))
1754 && real_zerop (TREE_IMAGPART (expr))));
1757 /* Return 1 if EXPR is the real constant one in real or complex form. */
1765 return ((TREE_CODE (expr) == REAL_CST
1766 && ! TREE_CONSTANT_OVERFLOW (expr)
1767 && REAL_VALUES_EQUAL (TREE_REAL_CST (expr), dconst1))
1768 || (TREE_CODE (expr) == COMPLEX_CST
1769 && real_onep (TREE_REALPART (expr))
1770 && real_zerop (TREE_IMAGPART (expr))));
1773 /* Return 1 if EXPR is the real constant two. */
1781 return ((TREE_CODE (expr) == REAL_CST
1782 && ! TREE_CONSTANT_OVERFLOW (expr)
1783 && REAL_VALUES_EQUAL (TREE_REAL_CST (expr), dconst2))
1784 || (TREE_CODE (expr) == COMPLEX_CST
1785 && real_twop (TREE_REALPART (expr))
1786 && real_zerop (TREE_IMAGPART (expr))));
1789 /* Nonzero if EXP is a constant or a cast of a constant. */
1792 really_constant_p (exp)
1795 /* This is not quite the same as STRIP_NOPS. It does more. */
1796 while (TREE_CODE (exp) == NOP_EXPR
1797 || TREE_CODE (exp) == CONVERT_EXPR
1798 || TREE_CODE (exp) == NON_LVALUE_EXPR)
1799 exp = TREE_OPERAND (exp, 0);
1800 return TREE_CONSTANT (exp);
1803 /* Return first list element whose TREE_VALUE is ELEM.
1804 Return 0 if ELEM is not in LIST. */
1807 value_member (elem, list)
1812 if (elem == TREE_VALUE (list))
1814 list = TREE_CHAIN (list);
1819 /* Return first list element whose TREE_PURPOSE is ELEM.
1820 Return 0 if ELEM is not in LIST. */
1823 purpose_member (elem, list)
1828 if (elem == TREE_PURPOSE (list))
1830 list = TREE_CHAIN (list);
1835 /* Return first list element whose BINFO_TYPE is ELEM.
1836 Return 0 if ELEM is not in LIST. */
1839 binfo_member (elem, list)
1844 if (elem == BINFO_TYPE (list))
1846 list = TREE_CHAIN (list);
1851 /* Return nonzero if ELEM is part of the chain CHAIN. */
1854 chain_member (elem, chain)
1861 chain = TREE_CHAIN (chain);
1867 /* Return nonzero if ELEM is equal to TREE_VALUE (CHAIN) for any piece of
1869 /* ??? This function was added for machine specific attributes but is no
1870 longer used. It could be deleted if we could confirm all front ends
1874 chain_member_value (elem, chain)
1879 if (elem == TREE_VALUE (chain))
1881 chain = TREE_CHAIN (chain);
1887 /* Return nonzero if ELEM is equal to TREE_PURPOSE (CHAIN)
1888 for any piece of chain CHAIN. */
1889 /* ??? This function was added for machine specific attributes but is no
1890 longer used. It could be deleted if we could confirm all front ends
1894 chain_member_purpose (elem, chain)
1899 if (elem == TREE_PURPOSE (chain))
1901 chain = TREE_CHAIN (chain);
1907 /* Return the length of a chain of nodes chained through TREE_CHAIN.
1908 We expect a null pointer to mark the end of the chain.
1909 This is the Lisp primitive `length'. */
1916 register int len = 0;
1918 for (tail = t; tail; tail = TREE_CHAIN (tail))
1924 /* Concatenate two chains of nodes (chained through TREE_CHAIN)
1925 by modifying the last node in chain 1 to point to chain 2.
1926 This is the Lisp primitive `nconc'. */
1938 for (t1 = op1; TREE_CHAIN (t1); t1 = TREE_CHAIN (t1))
1940 TREE_CHAIN (t1) = op2;
1941 for (t2 = op2; t2; t2 = TREE_CHAIN (t2))
1943 abort (); /* Circularity created. */
1949 /* Return the last node in a chain of nodes (chained through TREE_CHAIN). */
1953 register tree chain;
1957 while ((next = TREE_CHAIN (chain)))
1962 /* Reverse the order of elements in the chain T,
1963 and return the new head of the chain (old last element). */
1969 register tree prev = 0, decl, next;
1970 for (decl = t; decl; decl = next)
1972 next = TREE_CHAIN (decl);
1973 TREE_CHAIN (decl) = prev;
1979 /* Given a chain CHAIN of tree nodes,
1980 construct and return a list of those nodes. */
1986 tree result = NULL_TREE;
1987 tree in_tail = chain;
1988 tree out_tail = NULL_TREE;
1992 tree next = tree_cons (NULL_TREE, in_tail, NULL_TREE);
1994 TREE_CHAIN (out_tail) = next;
1998 in_tail = TREE_CHAIN (in_tail);
2004 /* Return a newly created TREE_LIST node whose
2005 purpose and value fields are PARM and VALUE. */
2008 build_tree_list (parm, value)
2011 register tree t = make_node (TREE_LIST);
2012 TREE_PURPOSE (t) = parm;
2013 TREE_VALUE (t) = value;
2017 /* Similar, but build on the temp_decl_obstack. */
2020 build_decl_list (parm, value)
2024 register struct obstack *ambient_obstack = current_obstack;
2025 current_obstack = &temp_decl_obstack;
2026 node = build_tree_list (parm, value);
2027 current_obstack = ambient_obstack;
2031 /* Similar, but build on the expression_obstack. */
2034 build_expr_list (parm, value)
2038 register struct obstack *ambient_obstack = current_obstack;
2039 current_obstack = expression_obstack;
2040 node = build_tree_list (parm, value);
2041 current_obstack = ambient_obstack;
2045 /* Return a newly created TREE_LIST node whose
2046 purpose and value fields are PARM and VALUE
2047 and whose TREE_CHAIN is CHAIN. */
2050 tree_cons (purpose, value, chain)
2051 tree purpose, value, chain;
2054 register tree node = make_node (TREE_LIST);
2057 register tree node = (tree) obstack_alloc (current_obstack, sizeof (struct tree_list));
2058 #ifdef GATHER_STATISTICS
2059 tree_node_counts[(int)x_kind]++;
2060 tree_node_sizes[(int)x_kind] += sizeof (struct tree_list);
2063 for (i = (sizeof (struct tree_common) / sizeof (int)) - 1; i >= 0; i--)
2064 ((int *) node)[i] = 0;
2066 TREE_SET_CODE (node, TREE_LIST);
2067 if (current_obstack == &permanent_obstack)
2068 TREE_PERMANENT (node) = 1;
2071 TREE_CHAIN (node) = chain;
2072 TREE_PURPOSE (node) = purpose;
2073 TREE_VALUE (node) = value;
2077 /* Similar, but build on the temp_decl_obstack. */
2080 decl_tree_cons (purpose, value, chain)
2081 tree purpose, value, chain;
2084 register struct obstack *ambient_obstack = current_obstack;
2085 current_obstack = &temp_decl_obstack;
2086 node = tree_cons (purpose, value, chain);
2087 current_obstack = ambient_obstack;
2091 /* Similar, but build on the expression_obstack. */
2094 expr_tree_cons (purpose, value, chain)
2095 tree purpose, value, chain;
2098 register struct obstack *ambient_obstack = current_obstack;
2099 current_obstack = expression_obstack;
2100 node = tree_cons (purpose, value, chain);
2101 current_obstack = ambient_obstack;
2105 /* Same as `tree_cons' but make a permanent object. */
2108 perm_tree_cons (purpose, value, chain)
2109 tree purpose, value, chain;
2112 register struct obstack *ambient_obstack = current_obstack;
2113 current_obstack = &permanent_obstack;
2115 node = tree_cons (purpose, value, chain);
2116 current_obstack = ambient_obstack;
2120 /* Same as `tree_cons', but make this node temporary, regardless. */
2123 temp_tree_cons (purpose, value, chain)
2124 tree purpose, value, chain;
2127 register struct obstack *ambient_obstack = current_obstack;
2128 current_obstack = &temporary_obstack;
2130 node = tree_cons (purpose, value, chain);
2131 current_obstack = ambient_obstack;
2135 /* Same as `tree_cons', but save this node if the function's RTL is saved. */
2138 saveable_tree_cons (purpose, value, chain)
2139 tree purpose, value, chain;
2142 register struct obstack *ambient_obstack = current_obstack;
2143 current_obstack = saveable_obstack;
2145 node = tree_cons (purpose, value, chain);
2146 current_obstack = ambient_obstack;
2150 /* Return the size nominally occupied by an object of type TYPE
2151 when it resides in memory. The value is measured in units of bytes,
2152 and its data type is that normally used for type sizes
2153 (which is the first type created by make_signed_type or
2154 make_unsigned_type). */
2157 size_in_bytes (type)
2162 if (type == error_mark_node)
2163 return integer_zero_node;
2164 type = TYPE_MAIN_VARIANT (type);
2165 if (TYPE_SIZE (type) == 0)
2167 incomplete_type_error (NULL_TREE, type);
2168 return integer_zero_node;
2170 t = size_binop (CEIL_DIV_EXPR, TYPE_SIZE (type),
2171 size_int (BITS_PER_UNIT));
2172 if (TREE_CODE (t) == INTEGER_CST)
2173 force_fit_type (t, 0);
2177 /* Return the size of TYPE (in bytes) as a wide integer
2178 or return -1 if the size can vary or is larger than an integer. */
2181 int_size_in_bytes (type)
2186 if (type == error_mark_node)
2189 type = TYPE_MAIN_VARIANT (type);
2190 if (TYPE_SIZE (type) == 0
2191 || TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
2194 if (TREE_INT_CST_HIGH (TYPE_SIZE (type)) == 0)
2195 return ((TREE_INT_CST_LOW (TYPE_SIZE (type)) + BITS_PER_UNIT - 1)
2198 t = size_binop (CEIL_DIV_EXPR, TYPE_SIZE (type), size_int (BITS_PER_UNIT));
2199 if (TREE_CODE (t) != INTEGER_CST || TREE_INT_CST_HIGH (t) != 0)
2202 return TREE_INT_CST_LOW (t);
2205 /* Return, as a tree node, the number of elements for TYPE (which is an
2206 ARRAY_TYPE) minus one. This counts only elements of the top array.
2208 Don't let any SAVE_EXPRs escape; if we are called as part of a cleanup
2209 action, they would get unsaved. */
2212 array_type_nelts (type)
2215 tree index_type, min, max;
2217 /* If they did it with unspecified bounds, then we should have already
2218 given an error about it before we got here. */
2219 if (! TYPE_DOMAIN (type))
2220 return error_mark_node;
2222 index_type = TYPE_DOMAIN (type);
2223 min = TYPE_MIN_VALUE (index_type);
2224 max = TYPE_MAX_VALUE (index_type);
2226 if (! TREE_CONSTANT (min))
2229 if (TREE_CODE (min) == SAVE_EXPR)
2230 min = build (RTL_EXPR, TREE_TYPE (TYPE_MIN_VALUE (index_type)), 0,
2231 SAVE_EXPR_RTL (min));
2233 min = TYPE_MIN_VALUE (index_type);
2236 if (! TREE_CONSTANT (max))
2239 if (TREE_CODE (max) == SAVE_EXPR)
2240 max = build (RTL_EXPR, TREE_TYPE (TYPE_MAX_VALUE (index_type)), 0,
2241 SAVE_EXPR_RTL (max));
2243 max = TYPE_MAX_VALUE (index_type);
2246 return (integer_zerop (min)
2248 : fold (build (MINUS_EXPR, TREE_TYPE (max), max, min)));
2251 /* Return nonzero if arg is static -- a reference to an object in
2252 static storage. This is not the same as the C meaning of `static'. */
2258 switch (TREE_CODE (arg))
2261 /* Nested functions aren't static, since taking their address
2262 involves a trampoline. */
2263 return decl_function_context (arg) == 0 || DECL_NO_STATIC_CHAIN (arg);
2265 return TREE_STATIC (arg) || DECL_EXTERNAL (arg);
2268 return TREE_STATIC (arg);
2273 /* If we are referencing a bitfield, we can't evaluate an
2274 ADDR_EXPR at compile time and so it isn't a constant. */
2276 return (! DECL_BIT_FIELD (TREE_OPERAND (arg, 1))
2277 && staticp (TREE_OPERAND (arg, 0)));
2283 /* This case is technically correct, but results in setting
2284 TREE_CONSTANT on ADDR_EXPRs that cannot be evaluated at
2287 return TREE_CONSTANT (TREE_OPERAND (arg, 0));
2291 if (TREE_CODE (TYPE_SIZE (TREE_TYPE (arg))) == INTEGER_CST
2292 && TREE_CODE (TREE_OPERAND (arg, 1)) == INTEGER_CST)
2293 return staticp (TREE_OPERAND (arg, 0));
2300 /* Wrap a SAVE_EXPR around EXPR, if appropriate.
2301 Do this to any expression which may be used in more than one place,
2302 but must be evaluated only once.
2304 Normally, expand_expr would reevaluate the expression each time.
2305 Calling save_expr produces something that is evaluated and recorded
2306 the first time expand_expr is called on it. Subsequent calls to
2307 expand_expr just reuse the recorded value.
2309 The call to expand_expr that generates code that actually computes
2310 the value is the first call *at compile time*. Subsequent calls
2311 *at compile time* generate code to use the saved value.
2312 This produces correct result provided that *at run time* control
2313 always flows through the insns made by the first expand_expr
2314 before reaching the other places where the save_expr was evaluated.
2315 You, the caller of save_expr, must make sure this is so.
2317 Constants, and certain read-only nodes, are returned with no
2318 SAVE_EXPR because that is safe. Expressions containing placeholders
2319 are not touched; see tree.def for an explanation of what these
2326 register tree t = fold (expr);
2328 /* We don't care about whether this can be used as an lvalue in this
2330 while (TREE_CODE (t) == NON_LVALUE_EXPR)
2331 t = TREE_OPERAND (t, 0);
2333 /* If the tree evaluates to a constant, then we don't want to hide that
2334 fact (i.e. this allows further folding, and direct checks for constants).
2335 However, a read-only object that has side effects cannot be bypassed.
2336 Since it is no problem to reevaluate literals, we just return the
2339 if (TREE_CONSTANT (t) || (TREE_READONLY (t) && ! TREE_SIDE_EFFECTS (t))
2340 || TREE_CODE (t) == SAVE_EXPR || TREE_CODE (t) == ERROR_MARK)
2343 /* If T contains a PLACEHOLDER_EXPR, we must evaluate it each time, since
2344 it means that the size or offset of some field of an object depends on
2345 the value within another field.
2347 Note that it must not be the case that T contains both a PLACEHOLDER_EXPR
2348 and some variable since it would then need to be both evaluated once and
2349 evaluated more than once. Front-ends must assure this case cannot
2350 happen by surrounding any such subexpressions in their own SAVE_EXPR
2351 and forcing evaluation at the proper time. */
2352 if (contains_placeholder_p (t))
2355 t = build (SAVE_EXPR, TREE_TYPE (expr), t, current_function_decl, NULL_TREE);
2357 /* This expression might be placed ahead of a jump to ensure that the
2358 value was computed on both sides of the jump. So make sure it isn't
2359 eliminated as dead. */
2360 TREE_SIDE_EFFECTS (t) = 1;
2364 /* Arrange for an expression to be expanded multiple independent
2365 times. This is useful for cleanup actions, as the backend can
2366 expand them multiple times in different places. */
2374 /* If this is already protected, no sense in protecting it again. */
2375 if (TREE_CODE (expr) == UNSAVE_EXPR)
2378 t = build1 (UNSAVE_EXPR, TREE_TYPE (expr), expr);
2379 TREE_SIDE_EFFECTS (t) = TREE_SIDE_EFFECTS (expr);
2383 /* Returns the index of the first non-tree operand for CODE, or the number
2384 of operands if all are trees. */
2388 enum tree_code code;
2398 case WITH_CLEANUP_EXPR:
2399 /* Should be defined to be 2. */
2401 case METHOD_CALL_EXPR:
2404 return tree_code_length [(int) code];
2408 /* Modify a tree in place so that all the evaluate only once things
2409 are cleared out. Return the EXPR given. */
2412 unsave_expr_now (expr)
2415 enum tree_code code;
2419 if (expr == NULL_TREE)
2422 code = TREE_CODE (expr);
2423 first_rtl = first_rtl_op (code);
2427 SAVE_EXPR_RTL (expr) = 0;
2431 TREE_OPERAND (expr, 1) = TREE_OPERAND (expr, 3);
2432 TREE_OPERAND (expr, 3) = NULL_TREE;
2436 /* I don't yet know how to emit a sequence multiple times. */
2437 if (RTL_EXPR_SEQUENCE (expr) != 0)
2442 CALL_EXPR_RTL (expr) = 0;
2443 if (TREE_OPERAND (expr, 1)
2444 && TREE_CODE (TREE_OPERAND (expr, 1)) == TREE_LIST)
2446 tree exp = TREE_OPERAND (expr, 1);
2449 unsave_expr_now (TREE_VALUE (exp));
2450 exp = TREE_CHAIN (exp);
2459 switch (TREE_CODE_CLASS (code))
2461 case 'c': /* a constant */
2462 case 't': /* a type node */
2463 case 'x': /* something random, like an identifier or an ERROR_MARK. */
2464 case 'd': /* A decl node */
2465 case 'b': /* A block node */
2468 case 'e': /* an expression */
2469 case 'r': /* a reference */
2470 case 's': /* an expression with side effects */
2471 case '<': /* a comparison expression */
2472 case '2': /* a binary arithmetic expression */
2473 case '1': /* a unary arithmetic expression */
2474 for (i = first_rtl - 1; i >= 0; i--)
2475 unsave_expr_now (TREE_OPERAND (expr, i));
2483 /* Return 1 if EXP contains a PLACEHOLDER_EXPR; i.e., if it represents a size
2484 or offset that depends on a field within a record. */
2487 contains_placeholder_p (exp)
2490 register enum tree_code code = TREE_CODE (exp);
2493 /* If we have a WITH_RECORD_EXPR, it "cancels" any PLACEHOLDER_EXPR
2494 in it since it is supplying a value for it. */
2495 if (code == WITH_RECORD_EXPR)
2497 else if (code == PLACEHOLDER_EXPR)
2500 switch (TREE_CODE_CLASS (code))
2503 /* Don't look at any PLACEHOLDER_EXPRs that might be in index or bit
2504 position computations since they will be converted into a
2505 WITH_RECORD_EXPR involving the reference, which will assume
2506 here will be valid. */
2507 return contains_placeholder_p (TREE_OPERAND (exp, 0));
2510 if (code == TREE_LIST)
2511 return (contains_placeholder_p (TREE_VALUE (exp))
2512 || (TREE_CHAIN (exp) != 0
2513 && contains_placeholder_p (TREE_CHAIN (exp))));
2522 /* Ignoring the first operand isn't quite right, but works best. */
2523 return contains_placeholder_p (TREE_OPERAND (exp, 1));
2530 return (contains_placeholder_p (TREE_OPERAND (exp, 0))
2531 || contains_placeholder_p (TREE_OPERAND (exp, 1))
2532 || contains_placeholder_p (TREE_OPERAND (exp, 2)));
2535 /* If we already know this doesn't have a placeholder, don't
2537 if (SAVE_EXPR_NOPLACEHOLDER (exp) || SAVE_EXPR_RTL (exp) != 0)
2540 SAVE_EXPR_NOPLACEHOLDER (exp) = 1;
2541 result = contains_placeholder_p (TREE_OPERAND (exp, 0));
2543 SAVE_EXPR_NOPLACEHOLDER (exp) = 0;
2548 return (TREE_OPERAND (exp, 1) != 0
2549 && contains_placeholder_p (TREE_OPERAND (exp, 1)));
2555 switch (tree_code_length[(int) code])
2558 return contains_placeholder_p (TREE_OPERAND (exp, 0));
2560 return (contains_placeholder_p (TREE_OPERAND (exp, 0))
2561 || contains_placeholder_p (TREE_OPERAND (exp, 1)));
2572 /* Return 1 if EXP contains any expressions that produce cleanups for an
2573 outer scope to deal with. Used by fold. */
2581 if (! TREE_SIDE_EFFECTS (exp))
2584 switch (TREE_CODE (exp))
2587 case WITH_CLEANUP_EXPR:
2590 case CLEANUP_POINT_EXPR:
2594 for (exp = TREE_OPERAND (exp, 1); exp; exp = TREE_CHAIN (exp))
2596 cmp = has_cleanups (TREE_VALUE (exp));
2606 /* This general rule works for most tree codes. All exceptions should be
2607 handled above. If this is a language-specific tree code, we can't
2608 trust what might be in the operand, so say we don't know
2610 if ((int) TREE_CODE (exp) >= (int) LAST_AND_UNUSED_TREE_CODE)
2613 nops = first_rtl_op (TREE_CODE (exp));
2614 for (i = 0; i < nops; i++)
2615 if (TREE_OPERAND (exp, i) != 0)
2617 int type = TREE_CODE_CLASS (TREE_CODE (TREE_OPERAND (exp, i)));
2618 if (type == 'e' || type == '<' || type == '1' || type == '2'
2619 || type == 'r' || type == 's')
2621 cmp = has_cleanups (TREE_OPERAND (exp, i));
2630 /* Given a tree EXP, a FIELD_DECL F, and a replacement value R,
2631 return a tree with all occurrences of references to F in a
2632 PLACEHOLDER_EXPR replaced by R. Note that we assume here that EXP
2633 contains only arithmetic expressions or a CALL_EXPR with a
2634 PLACEHOLDER_EXPR occurring only in its arglist. */
2637 substitute_in_expr (exp, f, r)
2642 enum tree_code code = TREE_CODE (exp);
2647 switch (TREE_CODE_CLASS (code))
2654 if (code == PLACEHOLDER_EXPR)
2656 else if (code == TREE_LIST)
2658 op0 = (TREE_CHAIN (exp) == 0
2659 ? 0 : substitute_in_expr (TREE_CHAIN (exp), f, r));
2660 op1 = substitute_in_expr (TREE_VALUE (exp), f, r);
2661 if (op0 == TREE_CHAIN (exp) && op1 == TREE_VALUE (exp))
2664 return tree_cons (TREE_PURPOSE (exp), op1, op0);
2673 switch (tree_code_length[(int) code])
2676 op0 = substitute_in_expr (TREE_OPERAND (exp, 0), f, r);
2677 if (op0 == TREE_OPERAND (exp, 0))
2680 new = fold (build1 (code, TREE_TYPE (exp), op0));
2684 /* An RTL_EXPR cannot contain a PLACEHOLDER_EXPR; a CONSTRUCTOR
2685 could, but we don't support it. */
2686 if (code == RTL_EXPR)
2688 else if (code == CONSTRUCTOR)
2691 op0 = substitute_in_expr (TREE_OPERAND (exp, 0), f, r);
2692 op1 = substitute_in_expr (TREE_OPERAND (exp, 1), f, r);
2693 if (op0 == TREE_OPERAND (exp, 0) && op1 == TREE_OPERAND (exp, 1))
2696 new = fold (build (code, TREE_TYPE (exp), op0, op1));
2700 /* It cannot be that anything inside a SAVE_EXPR contains a
2701 PLACEHOLDER_EXPR. */
2702 if (code == SAVE_EXPR)
2705 else if (code == CALL_EXPR)
2707 op1 = substitute_in_expr (TREE_OPERAND (exp, 1), f, r);
2708 if (op1 == TREE_OPERAND (exp, 1))
2711 return build (code, TREE_TYPE (exp),
2712 TREE_OPERAND (exp, 0), op1, NULL_TREE);
2715 else if (code != COND_EXPR)
2718 op0 = substitute_in_expr (TREE_OPERAND (exp, 0), f, r);
2719 op1 = substitute_in_expr (TREE_OPERAND (exp, 1), f, r);
2720 op2 = substitute_in_expr (TREE_OPERAND (exp, 2), f, r);
2721 if (op0 == TREE_OPERAND (exp, 0) && op1 == TREE_OPERAND (exp, 1)
2722 && op2 == TREE_OPERAND (exp, 2))
2725 new = fold (build (code, TREE_TYPE (exp), op0, op1, op2));
2738 /* If this expression is getting a value from a PLACEHOLDER_EXPR
2739 and it is the right field, replace it with R. */
2740 for (inner = TREE_OPERAND (exp, 0);
2741 TREE_CODE_CLASS (TREE_CODE (inner)) == 'r';
2742 inner = TREE_OPERAND (inner, 0))
2744 if (TREE_CODE (inner) == PLACEHOLDER_EXPR
2745 && TREE_OPERAND (exp, 1) == f)
2748 /* If this expression hasn't been completed let, leave it
2750 if (TREE_CODE (inner) == PLACEHOLDER_EXPR
2751 && TREE_TYPE (inner) == 0)
2754 op0 = substitute_in_expr (TREE_OPERAND (exp, 0), f, r);
2755 if (op0 == TREE_OPERAND (exp, 0))
2758 new = fold (build (code, TREE_TYPE (exp), op0,
2759 TREE_OPERAND (exp, 1)));
2763 op0 = substitute_in_expr (TREE_OPERAND (exp, 0), f, r);
2764 op1 = substitute_in_expr (TREE_OPERAND (exp, 1), f, r);
2765 op2 = substitute_in_expr (TREE_OPERAND (exp, 2), f, r);
2766 if (op0 == TREE_OPERAND (exp, 0) && op1 == TREE_OPERAND (exp, 1)
2767 && op2 == TREE_OPERAND (exp, 2))
2770 new = fold (build (code, TREE_TYPE (exp), op0, op1, op2));
2775 op0 = substitute_in_expr (TREE_OPERAND (exp, 0), f, r);
2776 if (op0 == TREE_OPERAND (exp, 0))
2779 new = fold (build1 (code, TREE_TYPE (exp), op0));
2791 TREE_READONLY (new) = TREE_READONLY (exp);
2795 /* Stabilize a reference so that we can use it any number of times
2796 without causing its operands to be evaluated more than once.
2797 Returns the stabilized reference. This works by means of save_expr,
2798 so see the caveats in the comments about save_expr.
2800 Also allows conversion expressions whose operands are references.
2801 Any other kind of expression is returned unchanged. */
2804 stabilize_reference (ref)
2807 register tree result;
2808 register enum tree_code code = TREE_CODE (ref);
2815 /* No action is needed in this case. */
2821 case FIX_TRUNC_EXPR:
2822 case FIX_FLOOR_EXPR:
2823 case FIX_ROUND_EXPR:
2825 result = build_nt (code, stabilize_reference (TREE_OPERAND (ref, 0)));
2829 result = build_nt (INDIRECT_REF,
2830 stabilize_reference_1 (TREE_OPERAND (ref, 0)));
2834 result = build_nt (COMPONENT_REF,
2835 stabilize_reference (TREE_OPERAND (ref, 0)),
2836 TREE_OPERAND (ref, 1));
2840 result = build_nt (BIT_FIELD_REF,
2841 stabilize_reference (TREE_OPERAND (ref, 0)),
2842 stabilize_reference_1 (TREE_OPERAND (ref, 1)),
2843 stabilize_reference_1 (TREE_OPERAND (ref, 2)));
2847 result = build_nt (ARRAY_REF,
2848 stabilize_reference (TREE_OPERAND (ref, 0)),
2849 stabilize_reference_1 (TREE_OPERAND (ref, 1)));
2853 /* We cannot wrap the first expression in a SAVE_EXPR, as then
2854 it wouldn't be ignored. This matters when dealing with
2856 return stabilize_reference_1 (ref);
2859 result = build1 (INDIRECT_REF, TREE_TYPE (ref),
2860 save_expr (build1 (ADDR_EXPR,
2861 build_pointer_type (TREE_TYPE (ref)),
2866 /* If arg isn't a kind of lvalue we recognize, make no change.
2867 Caller should recognize the error for an invalid lvalue. */
2872 return error_mark_node;
2875 TREE_TYPE (result) = TREE_TYPE (ref);
2876 TREE_READONLY (result) = TREE_READONLY (ref);
2877 TREE_SIDE_EFFECTS (result) = TREE_SIDE_EFFECTS (ref);
2878 TREE_THIS_VOLATILE (result) = TREE_THIS_VOLATILE (ref);
2879 TREE_RAISES (result) = TREE_RAISES (ref);
2884 /* Subroutine of stabilize_reference; this is called for subtrees of
2885 references. Any expression with side-effects must be put in a SAVE_EXPR
2886 to ensure that it is only evaluated once.
2888 We don't put SAVE_EXPR nodes around everything, because assigning very
2889 simple expressions to temporaries causes us to miss good opportunities
2890 for optimizations. Among other things, the opportunity to fold in the
2891 addition of a constant into an addressing mode often gets lost, e.g.
2892 "y[i+1] += x;". In general, we take the approach that we should not make
2893 an assignment unless we are forced into it - i.e., that any non-side effect
2894 operator should be allowed, and that cse should take care of coalescing
2895 multiple utterances of the same expression should that prove fruitful. */
2898 stabilize_reference_1 (e)
2901 register tree result;
2902 register enum tree_code code = TREE_CODE (e);
2904 /* We cannot ignore const expressions because it might be a reference
2905 to a const array but whose index contains side-effects. But we can
2906 ignore things that are actual constant or that already have been
2907 handled by this function. */
2909 if (TREE_CONSTANT (e) || code == SAVE_EXPR)
2912 switch (TREE_CODE_CLASS (code))
2922 /* If the expression has side-effects, then encase it in a SAVE_EXPR
2923 so that it will only be evaluated once. */
2924 /* The reference (r) and comparison (<) classes could be handled as
2925 below, but it is generally faster to only evaluate them once. */
2926 if (TREE_SIDE_EFFECTS (e))
2927 return save_expr (e);
2931 /* Constants need no processing. In fact, we should never reach
2936 /* Division is slow and tends to be compiled with jumps,
2937 especially the division by powers of 2 that is often
2938 found inside of an array reference. So do it just once. */
2939 if (code == TRUNC_DIV_EXPR || code == TRUNC_MOD_EXPR
2940 || code == FLOOR_DIV_EXPR || code == FLOOR_MOD_EXPR
2941 || code == CEIL_DIV_EXPR || code == CEIL_MOD_EXPR
2942 || code == ROUND_DIV_EXPR || code == ROUND_MOD_EXPR)
2943 return save_expr (e);
2944 /* Recursively stabilize each operand. */
2945 result = build_nt (code, stabilize_reference_1 (TREE_OPERAND (e, 0)),
2946 stabilize_reference_1 (TREE_OPERAND (e, 1)));
2950 /* Recursively stabilize each operand. */
2951 result = build_nt (code, stabilize_reference_1 (TREE_OPERAND (e, 0)));
2958 TREE_TYPE (result) = TREE_TYPE (e);
2959 TREE_READONLY (result) = TREE_READONLY (e);
2960 TREE_SIDE_EFFECTS (result) = TREE_SIDE_EFFECTS (e);
2961 TREE_THIS_VOLATILE (result) = TREE_THIS_VOLATILE (e);
2962 TREE_RAISES (result) = TREE_RAISES (e);
2967 /* Low-level constructors for expressions. */
2969 /* Build an expression of code CODE, data type TYPE,
2970 and operands as specified by the arguments ARG1 and following arguments.
2971 Expressions and reference nodes can be created this way.
2972 Constants, decls, types and misc nodes cannot be. */
2975 build VPROTO((enum tree_code code, tree tt, ...))
2978 enum tree_code code;
2983 register int length;
2989 code = va_arg (p, enum tree_code);
2990 tt = va_arg (p, tree);
2993 t = make_node (code);
2994 length = tree_code_length[(int) code];
2999 /* This is equivalent to the loop below, but faster. */
3000 register tree arg0 = va_arg (p, tree);
3001 register tree arg1 = va_arg (p, tree);
3002 TREE_OPERAND (t, 0) = arg0;
3003 TREE_OPERAND (t, 1) = arg1;
3004 if ((arg0 && TREE_SIDE_EFFECTS (arg0))
3005 || (arg1 && TREE_SIDE_EFFECTS (arg1)))
3006 TREE_SIDE_EFFECTS (t) = 1;
3008 = (arg0 && TREE_RAISES (arg0)) || (arg1 && TREE_RAISES (arg1));
3010 else if (length == 1)
3012 register tree arg0 = va_arg (p, tree);
3014 /* Call build1 for this! */
3015 if (TREE_CODE_CLASS (code) != 's')
3017 TREE_OPERAND (t, 0) = arg0;
3018 if (arg0 && TREE_SIDE_EFFECTS (arg0))
3019 TREE_SIDE_EFFECTS (t) = 1;
3020 TREE_RAISES (t) = (arg0 && TREE_RAISES (arg0));
3024 for (i = 0; i < length; i++)
3026 register tree operand = va_arg (p, tree);
3027 TREE_OPERAND (t, i) = operand;
3030 if (TREE_SIDE_EFFECTS (operand))
3031 TREE_SIDE_EFFECTS (t) = 1;
3032 if (TREE_RAISES (operand))
3033 TREE_RAISES (t) = 1;
3041 /* Same as above, but only builds for unary operators.
3042 Saves lions share of calls to `build'; cuts down use
3043 of varargs, which is expensive for RISC machines. */
3046 build1 (code, type, node)
3047 enum tree_code code;
3051 register struct obstack *obstack = expression_obstack;
3052 register int i, length;
3053 #ifdef GATHER_STATISTICS
3054 register tree_node_kind kind;
3058 #ifdef GATHER_STATISTICS
3059 if (TREE_CODE_CLASS (code) == 'r')
3065 length = sizeof (struct tree_exp);
3067 t = (tree) obstack_alloc (obstack, length);
3069 #ifdef GATHER_STATISTICS
3070 tree_node_counts[(int)kind]++;
3071 tree_node_sizes[(int)kind] += length;
3074 for (i = (length / sizeof (int)) - 1; i >= 0; i--)
3077 TREE_TYPE (t) = type;
3078 TREE_SET_CODE (t, code);
3080 if (obstack == &permanent_obstack)
3081 TREE_PERMANENT (t) = 1;
3083 TREE_OPERAND (t, 0) = node;
3086 if (TREE_SIDE_EFFECTS (node))
3087 TREE_SIDE_EFFECTS (t) = 1;
3088 if (TREE_RAISES (node))
3089 TREE_RAISES (t) = 1;
3095 /* Similar except don't specify the TREE_TYPE
3096 and leave the TREE_SIDE_EFFECTS as 0.
3097 It is permissible for arguments to be null,
3098 or even garbage if their values do not matter. */
3101 build_nt VPROTO((enum tree_code code, ...))
3104 enum tree_code code;
3108 register int length;
3114 code = va_arg (p, enum tree_code);
3117 t = make_node (code);
3118 length = tree_code_length[(int) code];
3120 for (i = 0; i < length; i++)
3121 TREE_OPERAND (t, i) = va_arg (p, tree);
3127 /* Similar to `build_nt', except we build
3128 on the temp_decl_obstack, regardless. */
3131 build_parse_node VPROTO((enum tree_code code, ...))
3134 enum tree_code code;
3136 register struct obstack *ambient_obstack = expression_obstack;
3139 register int length;
3145 code = va_arg (p, enum tree_code);
3148 expression_obstack = &temp_decl_obstack;
3150 t = make_node (code);
3151 length = tree_code_length[(int) code];
3153 for (i = 0; i < length; i++)
3154 TREE_OPERAND (t, i) = va_arg (p, tree);
3157 expression_obstack = ambient_obstack;
3162 /* Commented out because this wants to be done very
3163 differently. See cp-lex.c. */
3165 build_op_identifier (op1, op2)
3168 register tree t = make_node (OP_IDENTIFIER);
3169 TREE_PURPOSE (t) = op1;
3170 TREE_VALUE (t) = op2;
3175 /* Create a DECL_... node of code CODE, name NAME and data type TYPE.
3176 We do NOT enter this node in any sort of symbol table.
3178 layout_decl is used to set up the decl's storage layout.
3179 Other slots are initialized to 0 or null pointers. */
3182 build_decl (code, name, type)
3183 enum tree_code code;
3188 t = make_node (code);
3190 /* if (type == error_mark_node)
3191 type = integer_type_node; */
3192 /* That is not done, deliberately, so that having error_mark_node
3193 as the type can suppress useless errors in the use of this variable. */
3195 DECL_NAME (t) = name;
3196 DECL_ASSEMBLER_NAME (t) = name;
3197 TREE_TYPE (t) = type;
3199 if (code == VAR_DECL || code == PARM_DECL || code == RESULT_DECL)
3201 else if (code == FUNCTION_DECL)
3202 DECL_MODE (t) = FUNCTION_MODE;
3207 /* BLOCK nodes are used to represent the structure of binding contours
3208 and declarations, once those contours have been exited and their contents
3209 compiled. This information is used for outputting debugging info. */
3212 build_block (vars, tags, subblocks, supercontext, chain)
3213 tree vars, tags, subblocks, supercontext, chain;
3215 register tree block = make_node (BLOCK);
3216 BLOCK_VARS (block) = vars;
3217 BLOCK_TYPE_TAGS (block) = tags;
3218 BLOCK_SUBBLOCKS (block) = subblocks;
3219 BLOCK_SUPERCONTEXT (block) = supercontext;
3220 BLOCK_CHAIN (block) = chain;
3224 /* EXPR_WITH_FILE_LOCATION are used to keep track of the exact
3225 location where an expression or an identifier were encountered. It
3226 is necessary for languages where the frontend parser will handle
3227 recursively more than one file (Java is one of them). */
3230 build_expr_wfl (node, file, line, col)
3235 static char *last_file = 0;
3236 static tree last_filenode = NULL_TREE;
3237 register tree wfl = make_node (EXPR_WITH_FILE_LOCATION);
3239 EXPR_WFL_NODE (wfl) = node;
3240 EXPR_WFL_SET_LINECOL (wfl, line, col);
3241 if (file != last_file)
3244 last_filenode = file ? get_identifier (file) : NULL_TREE;
3246 EXPR_WFL_FILENAME_NODE (wfl) = last_filenode;
3249 TREE_SIDE_EFFECTS (wfl) = TREE_SIDE_EFFECTS (node);
3250 TREE_TYPE (wfl) = TREE_TYPE (node);
3255 /* Return a declaration like DDECL except that its DECL_MACHINE_ATTRIBUTE
3259 build_decl_attribute_variant (ddecl, attribute)
3260 tree ddecl, attribute;
3262 DECL_MACHINE_ATTRIBUTES (ddecl) = attribute;
3266 /* Return a type like TTYPE except that its TYPE_ATTRIBUTE
3269 Record such modified types already made so we don't make duplicates. */
3272 build_type_attribute_variant (ttype, attribute)
3273 tree ttype, attribute;
3275 if ( ! attribute_list_equal (TYPE_ATTRIBUTES (ttype), attribute))
3277 register int hashcode;
3278 register struct obstack *ambient_obstack = current_obstack;
3281 if (ambient_obstack != &permanent_obstack)
3282 current_obstack = TYPE_OBSTACK (ttype);
3284 ntype = copy_node (ttype);
3285 current_obstack = ambient_obstack;
3287 TYPE_POINTER_TO (ntype) = 0;
3288 TYPE_REFERENCE_TO (ntype) = 0;
3289 TYPE_ATTRIBUTES (ntype) = attribute;
3291 /* Create a new main variant of TYPE. */
3292 TYPE_MAIN_VARIANT (ntype) = ntype;
3293 TYPE_NEXT_VARIANT (ntype) = 0;
3294 TYPE_READONLY (ntype) = TYPE_VOLATILE (ntype) = 0;
3296 hashcode = TYPE_HASH (TREE_CODE (ntype))
3297 + TYPE_HASH (TREE_TYPE (ntype))
3298 + attribute_hash_list (attribute);
3300 switch (TREE_CODE (ntype))
3303 hashcode += TYPE_HASH (TYPE_ARG_TYPES (ntype));
3306 hashcode += TYPE_HASH (TYPE_DOMAIN (ntype));
3309 hashcode += TYPE_HASH (TYPE_MAX_VALUE (ntype));
3312 hashcode += TYPE_HASH (TYPE_PRECISION (ntype));
3318 ntype = type_hash_canon (hashcode, ntype);
3319 ttype = build_type_variant (ntype, TYPE_READONLY (ttype),
3320 TYPE_VOLATILE (ttype));
3326 /* Return a 1 if ATTR_NAME and ATTR_ARGS is valid for either declaration DECL
3327 or type TYPE and 0 otherwise. Validity is determined the configuration
3328 macros VALID_MACHINE_DECL_ATTRIBUTE and VALID_MACHINE_TYPE_ATTRIBUTE. */
3331 valid_machine_attribute (attr_name, attr_args, decl, type)
3332 tree attr_name, attr_args;
3337 #ifdef VALID_MACHINE_DECL_ATTRIBUTE
3338 tree decl_attr_list = decl != 0 ? DECL_MACHINE_ATTRIBUTES (decl) : 0;
3340 #ifdef VALID_MACHINE_TYPE_ATTRIBUTE
3341 tree type_attr_list = TYPE_ATTRIBUTES (type);
3344 if (TREE_CODE (attr_name) != IDENTIFIER_NODE)
3347 #ifdef VALID_MACHINE_DECL_ATTRIBUTE
3349 && VALID_MACHINE_DECL_ATTRIBUTE (decl, decl_attr_list, attr_name, attr_args))
3351 tree attr = lookup_attribute (IDENTIFIER_POINTER (attr_name),
3354 if (attr != NULL_TREE)
3356 /* Override existing arguments. Declarations are unique so we can
3357 modify this in place. */
3358 TREE_VALUE (attr) = attr_args;
3362 decl_attr_list = tree_cons (attr_name, attr_args, decl_attr_list);
3363 decl = build_decl_attribute_variant (decl, decl_attr_list);
3370 #ifdef VALID_MACHINE_TYPE_ATTRIBUTE
3371 if (VALID_MACHINE_TYPE_ATTRIBUTE (type, type_attr_list, attr_name, attr_args))
3373 tree attr = lookup_attribute (IDENTIFIER_POINTER (attr_name),
3376 if (attr != NULL_TREE)
3378 /* Override existing arguments.
3379 ??? This currently works since attribute arguments are not
3380 included in `attribute_hash_list'. Something more complicated
3381 may be needed in the future. */
3382 TREE_VALUE (attr) = attr_args;
3386 type_attr_list = tree_cons (attr_name, attr_args, type_attr_list);
3387 type = build_type_attribute_variant (type, type_attr_list);
3390 TREE_TYPE (decl) = type;
3394 /* Handle putting a type attribute on pointer-to-function-type by putting
3395 the attribute on the function type. */
3396 else if (POINTER_TYPE_P (type)
3397 && TREE_CODE (TREE_TYPE (type)) == FUNCTION_TYPE
3398 && VALID_MACHINE_TYPE_ATTRIBUTE (TREE_TYPE (type), type_attr_list,
3399 attr_name, attr_args))
3401 tree inner_type = TREE_TYPE (type);
3402 tree inner_attr_list = TYPE_ATTRIBUTES (inner_type);
3403 tree attr = lookup_attribute (IDENTIFIER_POINTER (attr_name),
3406 if (attr != NULL_TREE)
3407 TREE_VALUE (attr) = attr_args;
3410 inner_attr_list = tree_cons (attr_name, attr_args, inner_attr_list);
3411 inner_type = build_type_attribute_variant (inner_type,
3416 TREE_TYPE (decl) = build_pointer_type (inner_type);
3425 /* Return non-zero if IDENT is a valid name for attribute ATTR,
3428 We try both `text' and `__text__', ATTR may be either one. */
3429 /* ??? It might be a reasonable simplification to require ATTR to be only
3430 `text'. One might then also require attribute lists to be stored in
3431 their canonicalized form. */
3434 is_attribute_p (attr, ident)
3438 int ident_len, attr_len;
3441 if (TREE_CODE (ident) != IDENTIFIER_NODE)
3444 if (strcmp (attr, IDENTIFIER_POINTER (ident)) == 0)
3447 p = IDENTIFIER_POINTER (ident);
3448 ident_len = strlen (p);
3449 attr_len = strlen (attr);
3451 /* If ATTR is `__text__', IDENT must be `text'; and vice versa. */
3455 || attr[attr_len - 2] != '_'
3456 || attr[attr_len - 1] != '_')
3458 if (ident_len == attr_len - 4
3459 && strncmp (attr + 2, p, attr_len - 4) == 0)
3464 if (ident_len == attr_len + 4
3465 && p[0] == '_' && p[1] == '_'
3466 && p[ident_len - 2] == '_' && p[ident_len - 1] == '_'
3467 && strncmp (attr, p + 2, attr_len) == 0)
3474 /* Given an attribute name and a list of attributes, return a pointer to the
3475 attribute's list element if the attribute is part of the list, or NULL_TREE
3479 lookup_attribute (attr_name, list)
3485 for (l = list; l; l = TREE_CHAIN (l))
3487 if (TREE_CODE (TREE_PURPOSE (l)) != IDENTIFIER_NODE)
3489 if (is_attribute_p (attr_name, TREE_PURPOSE (l)))
3496 /* Return an attribute list that is the union of a1 and a2. */
3499 merge_attributes (a1, a2)
3500 register tree a1, a2;
3504 /* Either one unset? Take the set one. */
3506 if (! (attributes = a1))
3509 /* One that completely contains the other? Take it. */
3511 else if (a2 && ! attribute_list_contained (a1, a2))
3513 if (attribute_list_contained (a2, a1))
3517 /* Pick the longest list, and hang on the other list. */
3518 /* ??? For the moment we punt on the issue of attrs with args. */
3520 if (list_length (a1) < list_length (a2))
3521 attributes = a2, a2 = a1;
3523 for (; a2; a2 = TREE_CHAIN (a2))
3524 if (lookup_attribute (IDENTIFIER_POINTER (TREE_PURPOSE (a2)),
3525 attributes) == NULL_TREE)
3527 a1 = copy_node (a2);
3528 TREE_CHAIN (a1) = attributes;
3536 /* Given types T1 and T2, merge their attributes and return
3540 merge_machine_type_attributes (t1, t2)
3543 #ifdef MERGE_MACHINE_TYPE_ATTRIBUTES
3544 return MERGE_MACHINE_TYPE_ATTRIBUTES (t1, t2);
3546 return merge_attributes (TYPE_ATTRIBUTES (t1),
3547 TYPE_ATTRIBUTES (t2));
3551 /* Given decls OLDDECL and NEWDECL, merge their attributes and return
3555 merge_machine_decl_attributes (olddecl, newdecl)
3556 tree olddecl, newdecl;
3558 #ifdef MERGE_MACHINE_DECL_ATTRIBUTES
3559 return MERGE_MACHINE_DECL_ATTRIBUTES (olddecl, newdecl);
3561 return merge_attributes (DECL_MACHINE_ATTRIBUTES (olddecl),
3562 DECL_MACHINE_ATTRIBUTES (newdecl));
3566 /* Return a type like TYPE except that its TYPE_READONLY is CONSTP
3567 and its TYPE_VOLATILE is VOLATILEP.
3569 Such variant types already made are recorded so that duplicates
3572 A variant types should never be used as the type of an expression.
3573 Always copy the variant information into the TREE_READONLY
3574 and TREE_THIS_VOLATILE of the expression, and then give the expression
3575 as its type the "main variant", the variant whose TYPE_READONLY
3576 and TYPE_VOLATILE are zero. Use TYPE_MAIN_VARIANT to find the
3580 build_type_variant (type, constp, volatilep)
3582 int constp, volatilep;
3586 /* Treat any nonzero argument as 1. */
3588 volatilep = !!volatilep;
3590 /* Search the chain of variants to see if there is already one there just
3591 like the one we need to have. If so, use that existing one. We must
3592 preserve the TYPE_NAME, since there is code that depends on this. */
3594 for (t = TYPE_MAIN_VARIANT (type); t; t = TYPE_NEXT_VARIANT (t))
3595 if (constp == TYPE_READONLY (t) && volatilep == TYPE_VOLATILE (t)
3596 && TYPE_NAME (t) == TYPE_NAME (type))
3599 /* We need a new one. */
3601 t = build_type_copy (type);
3602 TYPE_READONLY (t) = constp;
3603 TYPE_VOLATILE (t) = volatilep;
3608 /* Create a new variant of TYPE, equivalent but distinct.
3609 This is so the caller can modify it. */
3612 build_type_copy (type)
3615 register tree t, m = TYPE_MAIN_VARIANT (type);
3616 register struct obstack *ambient_obstack = current_obstack;
3618 current_obstack = TYPE_OBSTACK (type);
3619 t = copy_node (type);
3620 current_obstack = ambient_obstack;
3622 TYPE_POINTER_TO (t) = 0;
3623 TYPE_REFERENCE_TO (t) = 0;
3625 /* Add this type to the chain of variants of TYPE. */
3626 TYPE_NEXT_VARIANT (t) = TYPE_NEXT_VARIANT (m);
3627 TYPE_NEXT_VARIANT (m) = t;
3632 /* Hashing of types so that we don't make duplicates.
3633 The entry point is `type_hash_canon'. */
3635 /* Each hash table slot is a bucket containing a chain
3636 of these structures. */
3640 struct type_hash *next; /* Next structure in the bucket. */
3641 int hashcode; /* Hash code of this type. */
3642 tree type; /* The type recorded here. */
3645 /* Now here is the hash table. When recording a type, it is added
3646 to the slot whose index is the hash code mod the table size.
3647 Note that the hash table is used for several kinds of types
3648 (function types, array types and array index range types, for now).
3649 While all these live in the same table, they are completely independent,
3650 and the hash code is computed differently for each of these. */
3652 #define TYPE_HASH_SIZE 59
3653 struct type_hash *type_hash_table[TYPE_HASH_SIZE];
3655 /* Compute a hash code for a list of types (chain of TREE_LIST nodes
3656 with types in the TREE_VALUE slots), by adding the hash codes
3657 of the individual types. */
3660 type_hash_list (list)
3663 register int hashcode;
3665 for (hashcode = 0, tail = list; tail; tail = TREE_CHAIN (tail))
3666 hashcode += TYPE_HASH (TREE_VALUE (tail));
3670 /* Look in the type hash table for a type isomorphic to TYPE.
3671 If one is found, return it. Otherwise return 0. */
3674 type_hash_lookup (hashcode, type)
3678 register struct type_hash *h;
3679 for (h = type_hash_table[hashcode % TYPE_HASH_SIZE]; h; h = h->next)
3680 if (h->hashcode == hashcode
3681 && TREE_CODE (h->type) == TREE_CODE (type)
3682 && TREE_TYPE (h->type) == TREE_TYPE (type)
3683 && attribute_list_equal (TYPE_ATTRIBUTES (h->type),
3684 TYPE_ATTRIBUTES (type))
3685 && (TYPE_MAX_VALUE (h->type) == TYPE_MAX_VALUE (type)
3686 || tree_int_cst_equal (TYPE_MAX_VALUE (h->type),
3687 TYPE_MAX_VALUE (type)))
3688 && (TYPE_MIN_VALUE (h->type) == TYPE_MIN_VALUE (type)
3689 || tree_int_cst_equal (TYPE_MIN_VALUE (h->type),
3690 TYPE_MIN_VALUE (type)))
3691 /* Note that TYPE_DOMAIN is TYPE_ARG_TYPES for FUNCTION_TYPE. */
3692 && (TYPE_DOMAIN (h->type) == TYPE_DOMAIN (type)
3693 || (TYPE_DOMAIN (h->type)
3694 && TREE_CODE (TYPE_DOMAIN (h->type)) == TREE_LIST
3695 && TYPE_DOMAIN (type)
3696 && TREE_CODE (TYPE_DOMAIN (type)) == TREE_LIST
3697 && type_list_equal (TYPE_DOMAIN (h->type),
3698 TYPE_DOMAIN (type)))))
3703 /* Add an entry to the type-hash-table
3704 for a type TYPE whose hash code is HASHCODE. */
3707 type_hash_add (hashcode, type)
3711 register struct type_hash *h;
3713 h = (struct type_hash *) oballoc (sizeof (struct type_hash));
3714 h->hashcode = hashcode;
3716 h->next = type_hash_table[hashcode % TYPE_HASH_SIZE];
3717 type_hash_table[hashcode % TYPE_HASH_SIZE] = h;
3720 /* Given TYPE, and HASHCODE its hash code, return the canonical
3721 object for an identical type if one already exists.
3722 Otherwise, return TYPE, and record it as the canonical object
3723 if it is a permanent object.
3725 To use this function, first create a type of the sort you want.
3726 Then compute its hash code from the fields of the type that
3727 make it different from other similar types.
3728 Then call this function and use the value.
3729 This function frees the type you pass in if it is a duplicate. */
3731 /* Set to 1 to debug without canonicalization. Never set by program. */
3732 int debug_no_type_hash = 0;
3735 type_hash_canon (hashcode, type)
3741 if (debug_no_type_hash)
3744 t1 = type_hash_lookup (hashcode, type);
3747 obstack_free (TYPE_OBSTACK (type), type);
3748 #ifdef GATHER_STATISTICS
3749 tree_node_counts[(int)t_kind]--;
3750 tree_node_sizes[(int)t_kind] -= sizeof (struct tree_type);
3755 /* If this is a permanent type, record it for later reuse. */
3756 if (TREE_PERMANENT (type))
3757 type_hash_add (hashcode, type);
3762 /* Compute a hash code for a list of attributes (chain of TREE_LIST nodes
3763 with names in the TREE_PURPOSE slots and args in the TREE_VALUE slots),
3764 by adding the hash codes of the individual attributes. */
3767 attribute_hash_list (list)
3770 register int hashcode;
3772 for (hashcode = 0, tail = list; tail; tail = TREE_CHAIN (tail))
3773 /* ??? Do we want to add in TREE_VALUE too? */
3774 hashcode += TYPE_HASH (TREE_PURPOSE (tail));
3778 /* Given two lists of attributes, return true if list l2 is
3779 equivalent to l1. */
3782 attribute_list_equal (l1, l2)
3785 return attribute_list_contained (l1, l2)
3786 && attribute_list_contained (l2, l1);
3789 /* Given two lists of attributes, return true if list L2 is
3790 completely contained within L1. */
3791 /* ??? This would be faster if attribute names were stored in a canonicalized
3792 form. Otherwise, if L1 uses `foo' and L2 uses `__foo__', the long method
3793 must be used to show these elements are equivalent (which they are). */
3794 /* ??? It's not clear that attributes with arguments will always be handled
3798 attribute_list_contained (l1, l2)
3801 register tree t1, t2;
3803 /* First check the obvious, maybe the lists are identical. */
3807 /* Maybe the lists are similar. */
3808 for (t1 = l1, t2 = l2;
3810 && TREE_PURPOSE (t1) == TREE_PURPOSE (t2)
3811 && TREE_VALUE (t1) == TREE_VALUE (t2);
3812 t1 = TREE_CHAIN (t1), t2 = TREE_CHAIN (t2));
3814 /* Maybe the lists are equal. */
3815 if (t1 == 0 && t2 == 0)
3818 for (; t2; t2 = TREE_CHAIN (t2))
3821 = lookup_attribute (IDENTIFIER_POINTER (TREE_PURPOSE (t2)), l1);
3823 if (attr == NULL_TREE)
3825 if (simple_cst_equal (TREE_VALUE (t2), TREE_VALUE (attr)) != 1)
3832 /* Given two lists of types
3833 (chains of TREE_LIST nodes with types in the TREE_VALUE slots)
3834 return 1 if the lists contain the same types in the same order.
3835 Also, the TREE_PURPOSEs must match. */
3838 type_list_equal (l1, l2)
3841 register tree t1, t2;
3843 for (t1 = l1, t2 = l2; t1 && t2; t1 = TREE_CHAIN (t1), t2 = TREE_CHAIN (t2))
3844 if (TREE_VALUE (t1) != TREE_VALUE (t2)
3845 || (TREE_PURPOSE (t1) != TREE_PURPOSE (t2)
3846 && ! (1 == simple_cst_equal (TREE_PURPOSE (t1), TREE_PURPOSE (t2))
3847 && (TREE_TYPE (TREE_PURPOSE (t1))
3848 == TREE_TYPE (TREE_PURPOSE (t2))))))
3854 /* Nonzero if integer constants T1 and T2
3855 represent the same constant value. */
3858 tree_int_cst_equal (t1, t2)
3863 if (t1 == 0 || t2 == 0)
3865 if (TREE_CODE (t1) == INTEGER_CST
3866 && TREE_CODE (t2) == INTEGER_CST
3867 && TREE_INT_CST_LOW (t1) == TREE_INT_CST_LOW (t2)
3868 && TREE_INT_CST_HIGH (t1) == TREE_INT_CST_HIGH (t2))
3873 /* Nonzero if integer constants T1 and T2 represent values that satisfy <.
3874 The precise way of comparison depends on their data type. */
3877 tree_int_cst_lt (t1, t2)
3883 if (!TREE_UNSIGNED (TREE_TYPE (t1)))
3884 return INT_CST_LT (t1, t2);
3885 return INT_CST_LT_UNSIGNED (t1, t2);
3888 /* Return an indication of the sign of the integer constant T.
3889 The return value is -1 if T < 0, 0 if T == 0, and 1 if T > 0.
3890 Note that -1 will never be returned it T's type is unsigned. */
3893 tree_int_cst_sgn (t)
3896 if (TREE_INT_CST_LOW (t) == 0 && TREE_INT_CST_HIGH (t) == 0)
3898 else if (TREE_UNSIGNED (TREE_TYPE (t)))
3900 else if (TREE_INT_CST_HIGH (t) < 0)
3906 /* Compare two constructor-element-type constants. Return 1 if the lists
3907 are known to be equal; otherwise return 0. */
3910 simple_cst_list_equal (l1, l2)
3913 while (l1 != NULL_TREE && l2 != NULL_TREE)
3915 if (simple_cst_equal (TREE_VALUE (l1), TREE_VALUE (l2)) != 1)
3918 l1 = TREE_CHAIN (l1);
3919 l2 = TREE_CHAIN (l2);
3925 /* Return truthvalue of whether T1 is the same tree structure as T2.
3926 Return 1 if they are the same.
3927 Return 0 if they are understandably different.
3928 Return -1 if either contains tree structure not understood by
3932 simple_cst_equal (t1, t2)
3935 register enum tree_code code1, code2;
3940 if (t1 == 0 || t2 == 0)
3943 code1 = TREE_CODE (t1);
3944 code2 = TREE_CODE (t2);
3946 if (code1 == NOP_EXPR || code1 == CONVERT_EXPR || code1 == NON_LVALUE_EXPR)
3947 if (code2 == NOP_EXPR || code2 == CONVERT_EXPR || code2 == NON_LVALUE_EXPR)
3948 return simple_cst_equal (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0));
3950 return simple_cst_equal (TREE_OPERAND (t1, 0), t2);
3951 else if (code2 == NOP_EXPR || code2 == CONVERT_EXPR
3952 || code2 == NON_LVALUE_EXPR)
3953 return simple_cst_equal (t1, TREE_OPERAND (t2, 0));
3961 return TREE_INT_CST_LOW (t1) == TREE_INT_CST_LOW (t2)
3962 && TREE_INT_CST_HIGH (t1) == TREE_INT_CST_HIGH (t2);
3965 return REAL_VALUES_IDENTICAL (TREE_REAL_CST (t1), TREE_REAL_CST (t2));
3968 return TREE_STRING_LENGTH (t1) == TREE_STRING_LENGTH (t2)
3969 && !bcmp (TREE_STRING_POINTER (t1), TREE_STRING_POINTER (t2),
3970 TREE_STRING_LENGTH (t1));
3976 return simple_cst_equal (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0));
3979 cmp = simple_cst_equal (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0));
3982 return simple_cst_list_equal (TREE_OPERAND (t1, 1), TREE_OPERAND (t2, 1));
3985 /* Special case: if either target is an unallocated VAR_DECL,
3986 it means that it's going to be unified with whatever the
3987 TARGET_EXPR is really supposed to initialize, so treat it
3988 as being equivalent to anything. */
3989 if ((TREE_CODE (TREE_OPERAND (t1, 0)) == VAR_DECL
3990 && DECL_NAME (TREE_OPERAND (t1, 0)) == NULL_TREE
3991 && DECL_RTL (TREE_OPERAND (t1, 0)) == 0)
3992 || (TREE_CODE (TREE_OPERAND (t2, 0)) == VAR_DECL
3993 && DECL_NAME (TREE_OPERAND (t2, 0)) == NULL_TREE
3994 && DECL_RTL (TREE_OPERAND (t2, 0)) == 0))
3997 cmp = simple_cst_equal (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0));
4000 return simple_cst_equal (TREE_OPERAND (t1, 1), TREE_OPERAND (t2, 1));
4002 case WITH_CLEANUP_EXPR:
4003 cmp = simple_cst_equal (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0));
4006 return simple_cst_equal (TREE_OPERAND (t1, 2), TREE_OPERAND (t1, 2));
4009 if (TREE_OPERAND (t1, 1) == TREE_OPERAND (t2, 1))
4010 return simple_cst_equal (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0));
4023 /* This general rule works for most tree codes. All exceptions should be
4024 handled above. If this is a language-specific tree code, we can't
4025 trust what might be in the operand, so say we don't know
4027 if ((int) code1 >= (int) LAST_AND_UNUSED_TREE_CODE)
4030 switch (TREE_CODE_CLASS (code1))
4040 for (i=0; i<tree_code_length[(int) code1]; ++i)
4042 cmp = simple_cst_equal (TREE_OPERAND (t1, i), TREE_OPERAND (t2, i));
4053 /* Constructors for pointer, array and function types.
4054 (RECORD_TYPE, UNION_TYPE and ENUMERAL_TYPE nodes are
4055 constructed by language-dependent code, not here.) */
4057 /* Construct, lay out and return the type of pointers to TO_TYPE.
4058 If such a type has already been constructed, reuse it. */
4061 build_pointer_type (to_type)
4064 register tree t = TYPE_POINTER_TO (to_type);
4066 /* First, if we already have a type for pointers to TO_TYPE, use it. */
4071 /* We need a new one. Put this in the same obstack as TO_TYPE. */
4072 push_obstacks (TYPE_OBSTACK (to_type), TYPE_OBSTACK (to_type));
4073 t = make_node (POINTER_TYPE);
4076 TREE_TYPE (t) = to_type;
4078 /* Record this type as the pointer to TO_TYPE. */
4079 TYPE_POINTER_TO (to_type) = t;
4081 /* Lay out the type. This function has many callers that are concerned
4082 with expression-construction, and this simplifies them all.
4083 Also, it guarantees the TYPE_SIZE is in the same obstack as the type. */
4089 /* Create a type of integers to be the TYPE_DOMAIN of an ARRAY_TYPE.
4090 MAXVAL should be the maximum value in the domain
4091 (one less than the length of the array).
4093 The maximum value that MAXVAL can have is INT_MAX for a HOST_WIDE_INT.
4094 We don't enforce this limit, that is up to caller (e.g. language front end).
4095 The limit exists because the result is a signed type and we don't handle
4096 sizes that use more than one HOST_WIDE_INT. */
4099 build_index_type (maxval)
4102 register tree itype = make_node (INTEGER_TYPE);
4104 TYPE_PRECISION (itype) = TYPE_PRECISION (sizetype);
4105 TYPE_MIN_VALUE (itype) = size_zero_node;
4107 push_obstacks (TYPE_OBSTACK (itype), TYPE_OBSTACK (itype));
4108 TYPE_MAX_VALUE (itype) = convert (sizetype, maxval);
4111 TYPE_MODE (itype) = TYPE_MODE (sizetype);
4112 TYPE_SIZE (itype) = TYPE_SIZE (sizetype);
4113 TYPE_ALIGN (itype) = TYPE_ALIGN (sizetype);
4114 if (TREE_CODE (maxval) == INTEGER_CST)
4116 int maxint = (int) TREE_INT_CST_LOW (maxval);
4117 /* If the domain should be empty, make sure the maxval
4118 remains -1 and is not spoiled by truncation. */
4119 if (INT_CST_LT (maxval, integer_zero_node))
4121 TYPE_MAX_VALUE (itype) = build_int_2 (-1, -1);
4122 TREE_TYPE (TYPE_MAX_VALUE (itype)) = sizetype;
4124 return type_hash_canon (maxint < 0 ? ~maxint : maxint, itype);
4130 /* Create a range of some discrete type TYPE (an INTEGER_TYPE,
4131 ENUMERAL_TYPE, BOOLEAN_TYPE, or CHAR_TYPE), with
4132 low bound LOWVAL and high bound HIGHVAL.
4133 if TYPE==NULL_TREE, sizetype is used. */
4136 build_range_type (type, lowval, highval)
4137 tree type, lowval, highval;
4139 register tree itype = make_node (INTEGER_TYPE);
4141 TREE_TYPE (itype) = type;
4142 if (type == NULL_TREE)
4145 push_obstacks (TYPE_OBSTACK (itype), TYPE_OBSTACK (itype));
4146 TYPE_MIN_VALUE (itype) = convert (type, lowval);
4147 TYPE_MAX_VALUE (itype) = highval ? convert (type, highval) : NULL;
4150 TYPE_PRECISION (itype) = TYPE_PRECISION (type);
4151 TYPE_MODE (itype) = TYPE_MODE (type);
4152 TYPE_SIZE (itype) = TYPE_SIZE (type);
4153 TYPE_ALIGN (itype) = TYPE_ALIGN (type);
4154 if (TREE_CODE (lowval) == INTEGER_CST)
4156 HOST_WIDE_INT lowint, highint;
4159 lowint = TREE_INT_CST_LOW (lowval);
4160 if (highval && TREE_CODE (highval) == INTEGER_CST)
4161 highint = TREE_INT_CST_LOW (highval);
4163 highint = (~(unsigned HOST_WIDE_INT)0) >> 1;
4165 maxint = (int) (highint - lowint);
4166 return type_hash_canon (maxint < 0 ? ~maxint : maxint, itype);
4172 /* Just like build_index_type, but takes lowval and highval instead
4173 of just highval (maxval). */
4176 build_index_2_type (lowval,highval)
4177 tree lowval, highval;
4179 return build_range_type (NULL_TREE, lowval, highval);
4182 /* Return nonzero iff ITYPE1 and ITYPE2 are equal (in the LISP sense).
4183 Needed because when index types are not hashed, equal index types
4184 built at different times appear distinct, even though structurally,
4188 index_type_equal (itype1, itype2)
4189 tree itype1, itype2;
4191 if (TREE_CODE (itype1) != TREE_CODE (itype2))
4193 if (TREE_CODE (itype1) == INTEGER_TYPE)
4195 if (TYPE_PRECISION (itype1) != TYPE_PRECISION (itype2)
4196 || TYPE_MODE (itype1) != TYPE_MODE (itype2)
4197 || simple_cst_equal (TYPE_SIZE (itype1), TYPE_SIZE (itype2)) != 1
4198 || TYPE_ALIGN (itype1) != TYPE_ALIGN (itype2))
4200 if (1 == simple_cst_equal (TYPE_MIN_VALUE (itype1),
4201 TYPE_MIN_VALUE (itype2))
4202 && 1 == simple_cst_equal (TYPE_MAX_VALUE (itype1),
4203 TYPE_MAX_VALUE (itype2)))
4210 /* Construct, lay out and return the type of arrays of elements with ELT_TYPE
4211 and number of elements specified by the range of values of INDEX_TYPE.
4212 If such a type has already been constructed, reuse it. */
4215 build_array_type (elt_type, index_type)
4216 tree elt_type, index_type;
4221 if (TREE_CODE (elt_type) == FUNCTION_TYPE)
4223 error ("arrays of functions are not meaningful");
4224 elt_type = integer_type_node;
4227 /* Make sure TYPE_POINTER_TO (elt_type) is filled in. */
4228 build_pointer_type (elt_type);
4230 /* Allocate the array after the pointer type,
4231 in case we free it in type_hash_canon. */
4232 t = make_node (ARRAY_TYPE);
4233 TREE_TYPE (t) = elt_type;
4234 TYPE_DOMAIN (t) = index_type;
4236 if (index_type == 0)
4241 hashcode = TYPE_HASH (elt_type) + TYPE_HASH (index_type);
4242 t = type_hash_canon (hashcode, t);
4244 if (TYPE_SIZE (t) == 0)
4249 /* Construct, lay out and return
4250 the type of functions returning type VALUE_TYPE
4251 given arguments of types ARG_TYPES.
4252 ARG_TYPES is a chain of TREE_LIST nodes whose TREE_VALUEs
4253 are data type nodes for the arguments of the function.
4254 If such a type has already been constructed, reuse it. */
4257 build_function_type (value_type, arg_types)
4258 tree value_type, arg_types;
4263 if (TREE_CODE (value_type) == FUNCTION_TYPE)
4265 error ("function return type cannot be function");
4266 value_type = integer_type_node;
4269 /* Make a node of the sort we want. */
4270 t = make_node (FUNCTION_TYPE);
4271 TREE_TYPE (t) = value_type;
4272 TYPE_ARG_TYPES (t) = arg_types;
4274 /* If we already have such a type, use the old one and free this one. */
4275 hashcode = TYPE_HASH (value_type) + type_hash_list (arg_types);
4276 t = type_hash_canon (hashcode, t);
4278 if (TYPE_SIZE (t) == 0)
4283 /* Build the node for the type of references-to-TO_TYPE. */
4286 build_reference_type (to_type)
4289 register tree t = TYPE_REFERENCE_TO (to_type);
4291 /* First, if we already have a type for pointers to TO_TYPE, use it. */
4296 /* We need a new one. Put this in the same obstack as TO_TYPE. */
4297 push_obstacks (TYPE_OBSTACK (to_type), TYPE_OBSTACK (to_type));
4298 t = make_node (REFERENCE_TYPE);
4301 TREE_TYPE (t) = to_type;
4303 /* Record this type as the pointer to TO_TYPE. */
4304 TYPE_REFERENCE_TO (to_type) = t;
4311 /* Construct, lay out and return the type of methods belonging to class
4312 BASETYPE and whose arguments and values are described by TYPE.
4313 If that type exists already, reuse it.
4314 TYPE must be a FUNCTION_TYPE node. */
4317 build_method_type (basetype, type)
4318 tree basetype, type;
4323 /* Make a node of the sort we want. */
4324 t = make_node (METHOD_TYPE);
4326 if (TREE_CODE (type) != FUNCTION_TYPE)
4329 TYPE_METHOD_BASETYPE (t) = TYPE_MAIN_VARIANT (basetype);
4330 TREE_TYPE (t) = TREE_TYPE (type);
4332 /* The actual arglist for this function includes a "hidden" argument
4333 which is "this". Put it into the list of argument types. */
4336 = tree_cons (NULL_TREE,
4337 build_pointer_type (basetype), TYPE_ARG_TYPES (type));
4339 /* If we already have such a type, use the old one and free this one. */
4340 hashcode = TYPE_HASH (basetype) + TYPE_HASH (type);
4341 t = type_hash_canon (hashcode, t);
4343 if (TYPE_SIZE (t) == 0)
4349 /* Construct, lay out and return the type of offsets to a value
4350 of type TYPE, within an object of type BASETYPE.
4351 If a suitable offset type exists already, reuse it. */
4354 build_offset_type (basetype, type)
4355 tree basetype, type;
4360 /* Make a node of the sort we want. */
4361 t = make_node (OFFSET_TYPE);
4363 TYPE_OFFSET_BASETYPE (t) = TYPE_MAIN_VARIANT (basetype);
4364 TREE_TYPE (t) = type;
4366 /* If we already have such a type, use the old one and free this one. */
4367 hashcode = TYPE_HASH (basetype) + TYPE_HASH (type);
4368 t = type_hash_canon (hashcode, t);
4370 if (TYPE_SIZE (t) == 0)
4376 /* Create a complex type whose components are COMPONENT_TYPE. */
4379 build_complex_type (component_type)
4380 tree component_type;
4385 /* Make a node of the sort we want. */
4386 t = make_node (COMPLEX_TYPE);
4388 TREE_TYPE (t) = TYPE_MAIN_VARIANT (component_type);
4389 TYPE_VOLATILE (t) = TYPE_VOLATILE (component_type);
4390 TYPE_READONLY (t) = TYPE_READONLY (component_type);
4392 /* If we already have such a type, use the old one and free this one. */
4393 hashcode = TYPE_HASH (component_type);
4394 t = type_hash_canon (hashcode, t);
4396 if (TYPE_SIZE (t) == 0)
4402 /* Return OP, stripped of any conversions to wider types as much as is safe.
4403 Converting the value back to OP's type makes a value equivalent to OP.
4405 If FOR_TYPE is nonzero, we return a value which, if converted to
4406 type FOR_TYPE, would be equivalent to converting OP to type FOR_TYPE.
4408 If FOR_TYPE is nonzero, unaligned bit-field references may be changed to the
4409 narrowest type that can hold the value, even if they don't exactly fit.
4410 Otherwise, bit-field references are changed to a narrower type
4411 only if they can be fetched directly from memory in that type.
4413 OP must have integer, real or enumeral type. Pointers are not allowed!
4415 There are some cases where the obvious value we could return
4416 would regenerate to OP if converted to OP's type,
4417 but would not extend like OP to wider types.
4418 If FOR_TYPE indicates such extension is contemplated, we eschew such values.
4419 For example, if OP is (unsigned short)(signed char)-1,
4420 we avoid returning (signed char)-1 if FOR_TYPE is int,
4421 even though extending that to an unsigned short would regenerate OP,
4422 since the result of extending (signed char)-1 to (int)
4423 is different from (int) OP. */
4426 get_unwidened (op, for_type)
4430 /* Set UNS initially if converting OP to FOR_TYPE is a zero-extension. */
4431 /* TYPE_PRECISION is safe in place of type_precision since
4432 pointer types are not allowed. */
4433 register tree type = TREE_TYPE (op);
4434 register unsigned final_prec
4435 = TYPE_PRECISION (for_type != 0 ? for_type : type);
4437 = (for_type != 0 && for_type != type
4438 && final_prec > TYPE_PRECISION (type)
4439 && TREE_UNSIGNED (type));
4440 register tree win = op;
4442 while (TREE_CODE (op) == NOP_EXPR)
4444 register int bitschange
4445 = TYPE_PRECISION (TREE_TYPE (op))
4446 - TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (op, 0)));
4448 /* Truncations are many-one so cannot be removed.
4449 Unless we are later going to truncate down even farther. */
4451 && final_prec > TYPE_PRECISION (TREE_TYPE (op)))
4454 /* See what's inside this conversion. If we decide to strip it,
4456 op = TREE_OPERAND (op, 0);
4458 /* If we have not stripped any zero-extensions (uns is 0),
4459 we can strip any kind of extension.
4460 If we have previously stripped a zero-extension,
4461 only zero-extensions can safely be stripped.
4462 Any extension can be stripped if the bits it would produce
4463 are all going to be discarded later by truncating to FOR_TYPE. */
4467 if (! uns || final_prec <= TYPE_PRECISION (TREE_TYPE (op)))
4469 /* TREE_UNSIGNED says whether this is a zero-extension.
4470 Let's avoid computing it if it does not affect WIN
4471 and if UNS will not be needed again. */
4472 if ((uns || TREE_CODE (op) == NOP_EXPR)
4473 && TREE_UNSIGNED (TREE_TYPE (op)))
4481 if (TREE_CODE (op) == COMPONENT_REF
4482 /* Since type_for_size always gives an integer type. */
4483 && TREE_CODE (type) != REAL_TYPE
4484 /* Don't crash if field not laid out yet. */
4485 && DECL_SIZE (TREE_OPERAND (op, 1)) != 0)
4487 unsigned innerprec = TREE_INT_CST_LOW (DECL_SIZE (TREE_OPERAND (op, 1)));
4488 type = type_for_size (innerprec, TREE_UNSIGNED (TREE_OPERAND (op, 1)));
4490 /* We can get this structure field in the narrowest type it fits in.
4491 If FOR_TYPE is 0, do this only for a field that matches the
4492 narrower type exactly and is aligned for it
4493 The resulting extension to its nominal type (a fullword type)
4494 must fit the same conditions as for other extensions. */
4496 if (innerprec < TYPE_PRECISION (TREE_TYPE (op))
4497 && (for_type || ! DECL_BIT_FIELD (TREE_OPERAND (op, 1)))
4498 && (! uns || final_prec <= innerprec
4499 || TREE_UNSIGNED (TREE_OPERAND (op, 1)))
4502 win = build (COMPONENT_REF, type, TREE_OPERAND (op, 0),
4503 TREE_OPERAND (op, 1));
4504 TREE_SIDE_EFFECTS (win) = TREE_SIDE_EFFECTS (op);
4505 TREE_THIS_VOLATILE (win) = TREE_THIS_VOLATILE (op);
4506 TREE_RAISES (win) = TREE_RAISES (op);
4512 /* Return OP or a simpler expression for a narrower value
4513 which can be sign-extended or zero-extended to give back OP.
4514 Store in *UNSIGNEDP_PTR either 1 if the value should be zero-extended
4515 or 0 if the value should be sign-extended. */
4518 get_narrower (op, unsignedp_ptr)
4522 register int uns = 0;
4524 register tree win = op;
4526 while (TREE_CODE (op) == NOP_EXPR)
4528 register int bitschange
4529 = TYPE_PRECISION (TREE_TYPE (op))
4530 - TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (op, 0)));
4532 /* Truncations are many-one so cannot be removed. */
4536 /* See what's inside this conversion. If we decide to strip it,
4538 op = TREE_OPERAND (op, 0);
4542 /* An extension: the outermost one can be stripped,
4543 but remember whether it is zero or sign extension. */
4545 uns = TREE_UNSIGNED (TREE_TYPE (op));
4546 /* Otherwise, if a sign extension has been stripped,
4547 only sign extensions can now be stripped;
4548 if a zero extension has been stripped, only zero-extensions. */
4549 else if (uns != TREE_UNSIGNED (TREE_TYPE (op)))
4553 else /* bitschange == 0 */
4555 /* A change in nominal type can always be stripped, but we must
4556 preserve the unsignedness. */
4558 uns = TREE_UNSIGNED (TREE_TYPE (op));
4565 if (TREE_CODE (op) == COMPONENT_REF
4566 /* Since type_for_size always gives an integer type. */
4567 && TREE_CODE (TREE_TYPE (op)) != REAL_TYPE)
4569 unsigned innerprec = TREE_INT_CST_LOW (DECL_SIZE (TREE_OPERAND (op, 1)));
4570 tree type = type_for_size (innerprec, TREE_UNSIGNED (op));
4572 /* We can get this structure field in a narrower type that fits it,
4573 but the resulting extension to its nominal type (a fullword type)
4574 must satisfy the same conditions as for other extensions.
4576 Do this only for fields that are aligned (not bit-fields),
4577 because when bit-field insns will be used there is no
4578 advantage in doing this. */
4580 if (innerprec < TYPE_PRECISION (TREE_TYPE (op))
4581 && ! DECL_BIT_FIELD (TREE_OPERAND (op, 1))
4582 && (first || uns == TREE_UNSIGNED (TREE_OPERAND (op, 1)))
4586 uns = TREE_UNSIGNED (TREE_OPERAND (op, 1));
4587 win = build (COMPONENT_REF, type, TREE_OPERAND (op, 0),
4588 TREE_OPERAND (op, 1));
4589 TREE_SIDE_EFFECTS (win) = TREE_SIDE_EFFECTS (op);
4590 TREE_THIS_VOLATILE (win) = TREE_THIS_VOLATILE (op);
4591 TREE_RAISES (win) = TREE_RAISES (op);
4594 *unsignedp_ptr = uns;
4598 /* Return the precision of a type, for arithmetic purposes.
4599 Supports all types on which arithmetic is possible
4600 (including pointer types).
4601 It's not clear yet what will be right for complex types. */
4604 type_precision (type)
4607 return ((TREE_CODE (type) == INTEGER_TYPE
4608 || TREE_CODE (type) == ENUMERAL_TYPE
4609 || TREE_CODE (type) == REAL_TYPE)
4610 ? TYPE_PRECISION (type) : POINTER_SIZE);
4613 /* Nonzero if integer constant C has a value that is permissible
4614 for type TYPE (an INTEGER_TYPE). */
4617 int_fits_type_p (c, type)
4620 if (TREE_UNSIGNED (type))
4621 return (! (TREE_CODE (TYPE_MAX_VALUE (type)) == INTEGER_CST
4622 && INT_CST_LT_UNSIGNED (TYPE_MAX_VALUE (type), c))
4623 && ! (TREE_CODE (TYPE_MIN_VALUE (type)) == INTEGER_CST
4624 && INT_CST_LT_UNSIGNED (c, TYPE_MIN_VALUE (type)))
4625 /* Negative ints never fit unsigned types. */
4626 && ! (TREE_INT_CST_HIGH (c) < 0
4627 && ! TREE_UNSIGNED (TREE_TYPE (c))));
4629 return (! (TREE_CODE (TYPE_MAX_VALUE (type)) == INTEGER_CST
4630 && INT_CST_LT (TYPE_MAX_VALUE (type), c))
4631 && ! (TREE_CODE (TYPE_MIN_VALUE (type)) == INTEGER_CST
4632 && INT_CST_LT (c, TYPE_MIN_VALUE (type)))
4633 /* Unsigned ints with top bit set never fit signed types. */
4634 && ! (TREE_INT_CST_HIGH (c) < 0
4635 && TREE_UNSIGNED (TREE_TYPE (c))));
4638 /* Return the innermost context enclosing DECL that is
4639 a FUNCTION_DECL, or zero if none. */
4642 decl_function_context (decl)
4647 if (TREE_CODE (decl) == ERROR_MARK)
4650 if (TREE_CODE (decl) == SAVE_EXPR)
4651 context = SAVE_EXPR_CONTEXT (decl);
4653 context = DECL_CONTEXT (decl);
4655 while (context && TREE_CODE (context) != FUNCTION_DECL)
4657 if (TREE_CODE (context) == RECORD_TYPE
4658 || TREE_CODE (context) == UNION_TYPE
4659 || TREE_CODE (context) == QUAL_UNION_TYPE)
4660 context = TYPE_CONTEXT (context);
4661 else if (TREE_CODE (context) == TYPE_DECL)
4662 context = DECL_CONTEXT (context);
4663 else if (TREE_CODE (context) == BLOCK)
4664 context = BLOCK_SUPERCONTEXT (context);
4666 /* Unhandled CONTEXT !? */
4673 /* Return the innermost context enclosing DECL that is
4674 a RECORD_TYPE, UNION_TYPE or QUAL_UNION_TYPE, or zero if none.
4675 TYPE_DECLs and FUNCTION_DECLs are transparent to this function. */
4678 decl_type_context (decl)
4681 tree context = DECL_CONTEXT (decl);
4685 if (TREE_CODE (context) == RECORD_TYPE
4686 || TREE_CODE (context) == UNION_TYPE
4687 || TREE_CODE (context) == QUAL_UNION_TYPE)
4689 if (TREE_CODE (context) == TYPE_DECL
4690 || TREE_CODE (context) == FUNCTION_DECL)
4691 context = DECL_CONTEXT (context);
4692 else if (TREE_CODE (context) == BLOCK)
4693 context = BLOCK_SUPERCONTEXT (context);
4695 /* Unhandled CONTEXT!? */
4701 /* Print debugging information about the size of the
4702 toplev_inline_obstacks. */
4705 print_inline_obstack_statistics ()
4707 struct simple_obstack_stack *current = toplev_inline_obstacks;
4712 for (; current; current = current->next, ++n_obstacks)
4714 struct obstack *o = current->obstack;
4715 struct _obstack_chunk *chunk = o->chunk;
4717 n_alloc += o->next_free - chunk->contents;
4718 chunk = chunk->prev;
4720 for (; chunk; chunk = chunk->prev, ++n_chunks)
4721 n_alloc += chunk->limit - &chunk->contents[0];
4723 fprintf (stderr, "inline obstacks: %d obstacks, %d bytes, %d chunks\n",
4724 n_obstacks, n_alloc, n_chunks);
4727 /* Print debugging information about the obstack O, named STR. */
4730 print_obstack_statistics (str, o)
4734 struct _obstack_chunk *chunk = o->chunk;
4738 n_alloc += o->next_free - chunk->contents;
4739 chunk = chunk->prev;
4743 n_alloc += chunk->limit - &chunk->contents[0];
4744 chunk = chunk->prev;
4746 fprintf (stderr, "obstack %s: %u bytes, %d chunks\n",
4747 str, n_alloc, n_chunks);
4750 /* Print debugging information about tree nodes generated during the compile,
4751 and any language-specific information. */
4754 dump_tree_statistics ()
4756 #ifdef GATHER_STATISTICS
4758 int total_nodes, total_bytes;
4761 fprintf (stderr, "\n??? tree nodes created\n\n");
4762 #ifdef GATHER_STATISTICS
4763 fprintf (stderr, "Kind Nodes Bytes\n");
4764 fprintf (stderr, "-------------------------------------\n");
4765 total_nodes = total_bytes = 0;
4766 for (i = 0; i < (int) all_kinds; i++)
4768 fprintf (stderr, "%-20s %6d %9d\n", tree_node_kind_names[i],
4769 tree_node_counts[i], tree_node_sizes[i]);
4770 total_nodes += tree_node_counts[i];
4771 total_bytes += tree_node_sizes[i];
4773 fprintf (stderr, "%-20s %9d\n", "identifier names", id_string_size);
4774 fprintf (stderr, "-------------------------------------\n");
4775 fprintf (stderr, "%-20s %6d %9d\n", "Total", total_nodes, total_bytes);
4776 fprintf (stderr, "-------------------------------------\n");
4778 fprintf (stderr, "(No per-node statistics)\n");
4780 print_obstack_statistics ("permanent_obstack", &permanent_obstack);
4781 print_obstack_statistics ("maybepermanent_obstack", &maybepermanent_obstack);
4782 print_obstack_statistics ("temporary_obstack", &temporary_obstack);
4783 print_obstack_statistics ("momentary_obstack", &momentary_obstack);
4784 print_obstack_statistics ("temp_decl_obstack", &temp_decl_obstack);
4785 print_inline_obstack_statistics ();
4786 print_lang_statistics ();
4789 #define FILE_FUNCTION_PREFIX_LEN 9
4791 #ifndef NO_DOLLAR_IN_LABEL
4792 #define FILE_FUNCTION_FORMAT "_GLOBAL_$D$%s"
4793 #else /* NO_DOLLAR_IN_LABEL */
4794 #ifndef NO_DOT_IN_LABEL
4795 #define FILE_FUNCTION_FORMAT "_GLOBAL_.D.%s"
4796 #else /* NO_DOT_IN_LABEL */
4797 #define FILE_FUNCTION_FORMAT "_GLOBAL__D_%s"
4798 #endif /* NO_DOT_IN_LABEL */
4799 #endif /* NO_DOLLAR_IN_LABEL */
4801 extern char * first_global_object_name;
4803 /* If KIND=='I', return a suitable global initializer (constructor) name.
4804 If KIND=='D', return a suitable global clean-up (destructor) name. */
4807 get_file_function_name (kind)
4813 if (first_global_object_name)
4814 p = first_global_object_name;
4815 else if (main_input_filename)
4816 p = main_input_filename;
4820 buf = (char *) alloca (sizeof (FILE_FUNCTION_FORMAT) + strlen (p));
4822 /* Set up the name of the file-level functions we may need. */
4823 /* Use a global object (which is already required to be unique over
4824 the program) rather than the file name (which imposes extra
4825 constraints). -- Raeburn@MIT.EDU, 10 Jan 1990. */
4826 sprintf (buf, FILE_FUNCTION_FORMAT, p);
4828 /* Don't need to pull weird characters out of global names. */
4829 if (p != first_global_object_name)
4831 for (p = buf+11; *p; p++)
4832 if (! ((*p >= '0' && *p <= '9')
4833 #if 0 /* we always want labels, which are valid C++ identifiers (+ `$') */
4834 #ifndef ASM_IDENTIFY_GCC /* this is required if `.' is invalid -- k. raeburn */
4838 #ifndef NO_DOLLAR_IN_LABEL /* this for `$'; unlikely, but... -- kr */
4841 #ifndef NO_DOT_IN_LABEL /* this for `.'; unlikely, but... */
4844 || (*p >= 'A' && *p <= 'Z')
4845 || (*p >= 'a' && *p <= 'z')))
4849 buf[FILE_FUNCTION_PREFIX_LEN] = kind;
4851 return get_identifier (buf);
4854 /* Expand (the constant part of) a SET_TYPE CONSTRUCTOR node.
4855 The result is placed in BUFFER (which has length BIT_SIZE),
4856 with one bit in each char ('\000' or '\001').
4858 If the constructor is constant, NULL_TREE is returned.
4859 Otherwise, a TREE_LIST of the non-constant elements is emitted. */
4862 get_set_constructor_bits (init, buffer, bit_size)
4869 HOST_WIDE_INT domain_min
4870 = TREE_INT_CST_LOW (TYPE_MIN_VALUE (TYPE_DOMAIN (TREE_TYPE (init))));
4871 tree non_const_bits = NULL_TREE;
4872 for (i = 0; i < bit_size; i++)
4875 for (vals = TREE_OPERAND (init, 1);
4876 vals != NULL_TREE; vals = TREE_CHAIN (vals))
4878 if (TREE_CODE (TREE_VALUE (vals)) != INTEGER_CST
4879 || (TREE_PURPOSE (vals) != NULL_TREE
4880 && TREE_CODE (TREE_PURPOSE (vals)) != INTEGER_CST))
4882 = tree_cons (TREE_PURPOSE (vals), TREE_VALUE (vals), non_const_bits);
4883 else if (TREE_PURPOSE (vals) != NULL_TREE)
4885 /* Set a range of bits to ones. */
4886 HOST_WIDE_INT lo_index
4887 = TREE_INT_CST_LOW (TREE_PURPOSE (vals)) - domain_min;
4888 HOST_WIDE_INT hi_index
4889 = TREE_INT_CST_LOW (TREE_VALUE (vals)) - domain_min;
4890 if (lo_index < 0 || lo_index >= bit_size
4891 || hi_index < 0 || hi_index >= bit_size)
4893 for ( ; lo_index <= hi_index; lo_index++)
4894 buffer[lo_index] = 1;
4898 /* Set a single bit to one. */
4900 = TREE_INT_CST_LOW (TREE_VALUE (vals)) - domain_min;
4901 if (index < 0 || index >= bit_size)
4903 error ("invalid initializer for bit string");
4909 return non_const_bits;
4912 /* Expand (the constant part of) a SET_TYPE CONSTRUCTOR node.
4913 The result is placed in BUFFER (which is an array of bytes).
4914 If the constructor is constant, NULL_TREE is returned.
4915 Otherwise, a TREE_LIST of the non-constant elements is emitted. */
4918 get_set_constructor_bytes (init, buffer, wd_size)
4920 unsigned char *buffer;
4924 int set_word_size = BITS_PER_UNIT;
4925 int bit_size = wd_size * set_word_size;
4927 unsigned char *bytep = buffer;
4928 char *bit_buffer = (char *) alloca(bit_size);
4929 tree non_const_bits = get_set_constructor_bits (init, bit_buffer, bit_size);
4931 for (i = 0; i < wd_size; i++)
4934 for (i = 0; i < bit_size; i++)
4938 if (BYTES_BIG_ENDIAN)
4939 *bytep |= (1 << (set_word_size - 1 - bit_pos));
4941 *bytep |= 1 << bit_pos;
4944 if (bit_pos >= set_word_size)
4945 bit_pos = 0, bytep++;
4947 return non_const_bits;