1 /* Language-independent node constructors for parse phase of GNU compiler.
2 Copyright (C) 1987, 88, 92-98, 1999 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. */
45 #define obstack_chunk_alloc xmalloc
46 #define obstack_chunk_free free
47 /* obstack.[ch] explicitly declined to prototype this. */
48 extern int _obstack_allocated_p PROTO ((struct obstack *h, GENERIC_PTR obj));
50 /* Tree nodes of permanent duration are allocated in this obstack.
51 They are the identifier nodes, and everything outside of
52 the bodies and parameters of function definitions. */
54 struct obstack permanent_obstack;
56 /* The initial RTL, and all ..._TYPE nodes, in a function
57 are allocated in this obstack. Usually they are freed at the
58 end of the function, but if the function is inline they are saved.
59 For top-level functions, this is maybepermanent_obstack.
60 Separate obstacks are made for nested functions. */
62 struct obstack *function_maybepermanent_obstack;
64 /* This is the function_maybepermanent_obstack for top-level functions. */
66 struct obstack maybepermanent_obstack;
68 /* This is a list of function_maybepermanent_obstacks for top-level inline
69 functions that are compiled in the middle of compiling other functions. */
71 struct simple_obstack_stack *toplev_inline_obstacks;
73 /* Former elements of toplev_inline_obstacks that have been recycled. */
75 struct simple_obstack_stack *extra_inline_obstacks;
77 /* This is a list of function_maybepermanent_obstacks for inline functions
78 nested in the current function that were compiled in the middle of
79 compiling other functions. */
81 struct simple_obstack_stack *inline_obstacks;
83 /* The contents of the current function definition are allocated
84 in this obstack, and all are freed at the end of the function.
85 For top-level functions, this is temporary_obstack.
86 Separate obstacks are made for nested functions. */
88 struct obstack *function_obstack;
90 /* This is used for reading initializers of global variables. */
92 struct obstack temporary_obstack;
94 /* The tree nodes of an expression are allocated
95 in this obstack, and all are freed at the end of the expression. */
97 struct obstack momentary_obstack;
99 /* The tree nodes of a declarator are allocated
100 in this obstack, and all are freed when the declarator
103 static struct obstack temp_decl_obstack;
105 /* This points at either permanent_obstack
106 or the current function_maybepermanent_obstack. */
108 struct obstack *saveable_obstack;
110 /* This is same as saveable_obstack during parse and expansion phase;
111 it points to the current function's obstack during optimization.
112 This is the obstack to be used for creating rtl objects. */
114 struct obstack *rtl_obstack;
116 /* This points at either permanent_obstack or the current function_obstack. */
118 struct obstack *current_obstack;
120 /* This points at either permanent_obstack or the current function_obstack
121 or momentary_obstack. */
123 struct obstack *expression_obstack;
125 /* Stack of obstack selections for push_obstacks and pop_obstacks. */
129 struct obstack_stack *next;
130 struct obstack *current;
131 struct obstack *saveable;
132 struct obstack *expression;
136 struct obstack_stack *obstack_stack;
138 /* Obstack for allocating struct obstack_stack entries. */
140 static struct obstack obstack_stack_obstack;
142 /* Addresses of first objects in some obstacks.
143 This is for freeing their entire contents. */
144 char *maybepermanent_firstobj;
145 char *temporary_firstobj;
146 char *momentary_firstobj;
147 char *temp_decl_firstobj;
149 /* This is used to preserve objects (mainly array initializers) that need to
150 live until the end of the current function, but no further. */
151 char *momentary_function_firstobj;
153 /* Nonzero means all ..._TYPE nodes should be allocated permanently. */
155 int all_types_permanent;
157 /* Stack of places to restore the momentary obstack back to. */
159 struct momentary_level
161 /* Pointer back to previous such level. */
162 struct momentary_level *prev;
163 /* First object allocated within this level. */
165 /* Value of expression_obstack saved at entry to this level. */
166 struct obstack *obstack;
169 struct momentary_level *momentary_stack;
171 /* Table indexed by tree code giving a string containing a character
172 classifying the tree code. Possibilities are
173 t, d, s, c, r, <, 1, 2 and e. See tree.def for details. */
175 #define DEFTREECODE(SYM, NAME, TYPE, LENGTH) TYPE,
177 char tree_code_type[MAX_TREE_CODES] = {
182 /* Table indexed by tree code giving number of expression
183 operands beyond the fixed part of the node structure.
184 Not used for types or decls. */
186 #define DEFTREECODE(SYM, NAME, TYPE, LENGTH) LENGTH,
188 int tree_code_length[MAX_TREE_CODES] = {
193 /* Names of tree components.
194 Used for printing out the tree and error messages. */
195 #define DEFTREECODE(SYM, NAME, TYPE, LEN) NAME,
197 char *tree_code_name[MAX_TREE_CODES] = {
202 /* Statistics-gathering stuff. */
223 int tree_node_counts[(int)all_kinds];
224 int tree_node_sizes[(int)all_kinds];
225 int id_string_size = 0;
227 const char *tree_node_kind_names[] = {
245 /* Hash table for uniquizing IDENTIFIER_NODEs by name. */
247 #define MAX_HASH_TABLE 1009
248 static tree hash_table[MAX_HASH_TABLE]; /* id hash buckets */
250 /* 0 while creating built-in identifiers. */
251 static int do_identifier_warnings;
253 /* Unique id for next decl created. */
254 static int next_decl_uid;
255 /* Unique id for next type created. */
256 static int next_type_uid = 1;
258 /* The language-specific function for alias analysis. If NULL, the
259 language does not do any special alias analysis. */
260 int (*lang_get_alias_set) PROTO((tree));
262 /* Here is how primitive or already-canonicalized types' hash
264 #define TYPE_HASH(TYPE) ((unsigned long) (TYPE) & 0777777)
266 static void set_type_quals PROTO((tree, int));
267 static void append_random_chars PROTO((char *));
268 static void build_real_from_int_cst_1 PROTO((PTR));
270 extern char *mode_name[];
272 void gcc_obstack_init ();
274 /* Init the principal obstacks. */
279 gcc_obstack_init (&obstack_stack_obstack);
280 gcc_obstack_init (&permanent_obstack);
282 gcc_obstack_init (&temporary_obstack);
283 temporary_firstobj = (char *) obstack_alloc (&temporary_obstack, 0);
284 gcc_obstack_init (&momentary_obstack);
285 momentary_firstobj = (char *) obstack_alloc (&momentary_obstack, 0);
286 momentary_function_firstobj = momentary_firstobj;
287 gcc_obstack_init (&maybepermanent_obstack);
288 maybepermanent_firstobj
289 = (char *) obstack_alloc (&maybepermanent_obstack, 0);
290 gcc_obstack_init (&temp_decl_obstack);
291 temp_decl_firstobj = (char *) obstack_alloc (&temp_decl_obstack, 0);
293 function_obstack = &temporary_obstack;
294 function_maybepermanent_obstack = &maybepermanent_obstack;
295 current_obstack = &permanent_obstack;
296 expression_obstack = &permanent_obstack;
297 rtl_obstack = saveable_obstack = &permanent_obstack;
299 /* Init the hash table of identifiers. */
300 bzero ((char *) hash_table, sizeof hash_table);
304 gcc_obstack_init (obstack)
305 struct obstack *obstack;
307 /* Let particular systems override the size of a chunk. */
308 #ifndef OBSTACK_CHUNK_SIZE
309 #define OBSTACK_CHUNK_SIZE 0
311 /* Let them override the alloc and free routines too. */
312 #ifndef OBSTACK_CHUNK_ALLOC
313 #define OBSTACK_CHUNK_ALLOC xmalloc
315 #ifndef OBSTACK_CHUNK_FREE
316 #define OBSTACK_CHUNK_FREE free
318 _obstack_begin (obstack, OBSTACK_CHUNK_SIZE, 0,
319 (void *(*) ()) OBSTACK_CHUNK_ALLOC,
320 (void (*) ()) OBSTACK_CHUNK_FREE);
323 /* Save all variables describing the current status into the structure
324 *P. This function is called whenever we start compiling one
325 function in the midst of compiling another. For example, when
326 compiling a nested function, or, in C++, a template instantiation
327 that is required by the function we are currently compiling.
329 CONTEXT is the decl_function_context for the function we're about to
330 compile; if it isn't current_function_decl, we have to play some games. */
333 save_tree_status (p, context)
337 p->all_types_permanent = all_types_permanent;
338 p->momentary_stack = momentary_stack;
339 p->maybepermanent_firstobj = maybepermanent_firstobj;
340 p->temporary_firstobj = temporary_firstobj;
341 p->momentary_firstobj = momentary_firstobj;
342 p->momentary_function_firstobj = momentary_function_firstobj;
343 p->function_obstack = function_obstack;
344 p->function_maybepermanent_obstack = function_maybepermanent_obstack;
345 p->current_obstack = current_obstack;
346 p->expression_obstack = expression_obstack;
347 p->saveable_obstack = saveable_obstack;
348 p->rtl_obstack = rtl_obstack;
349 p->inline_obstacks = inline_obstacks;
351 if (current_function_decl && context == current_function_decl)
352 /* Objects that need to be saved in this function can be in the nonsaved
353 obstack of the enclosing function since they can't possibly be needed
354 once it has returned. */
355 function_maybepermanent_obstack = function_obstack;
358 /* We're compiling a function which isn't nested in the current
359 function. We need to create a new maybepermanent_obstack for this
360 function, since it can't go onto any of the existing obstacks. */
361 struct simple_obstack_stack **head;
362 struct simple_obstack_stack *current;
364 if (context == NULL_TREE)
365 head = &toplev_inline_obstacks;
368 struct function *f = find_function_data (context);
369 head = &f->inline_obstacks;
372 if (context == NULL_TREE && extra_inline_obstacks)
374 current = extra_inline_obstacks;
375 extra_inline_obstacks = current->next;
379 current = ((struct simple_obstack_stack *)
380 xmalloc (sizeof (struct simple_obstack_stack)));
383 = (struct obstack *) xmalloc (sizeof (struct obstack));
384 gcc_obstack_init (current->obstack);
387 function_maybepermanent_obstack = current->obstack;
389 current->next = *head;
393 maybepermanent_firstobj
394 = (char *) obstack_finish (function_maybepermanent_obstack);
396 function_obstack = (struct obstack *) xmalloc (sizeof (struct obstack));
397 gcc_obstack_init (function_obstack);
399 current_obstack = &permanent_obstack;
400 expression_obstack = &permanent_obstack;
401 rtl_obstack = saveable_obstack = &permanent_obstack;
403 temporary_firstobj = (char *) obstack_alloc (&temporary_obstack, 0);
404 momentary_firstobj = (char *) obstack_finish (&momentary_obstack);
405 momentary_function_firstobj = momentary_firstobj;
408 /* Restore all variables describing the current status from the structure *P.
409 This is used after a nested function. */
412 restore_tree_status (p, context)
416 all_types_permanent = p->all_types_permanent;
417 momentary_stack = p->momentary_stack;
419 obstack_free (&momentary_obstack, momentary_function_firstobj);
421 /* Free saveable storage used by the function just compiled and not
424 CAUTION: This is in function_obstack of the containing function.
425 So we must be sure that we never allocate from that obstack during
426 the compilation of a nested function if we expect it to survive
427 past the nested function's end. */
428 obstack_free (function_maybepermanent_obstack, maybepermanent_firstobj);
430 /* If we were compiling a toplevel function, we can free this space now. */
431 if (context == NULL_TREE)
433 obstack_free (&temporary_obstack, temporary_firstobj);
434 obstack_free (&momentary_obstack, momentary_function_firstobj);
437 /* If we were compiling a toplevel function that we don't actually want
438 to save anything from, return the obstack to the pool. */
439 if (context == NULL_TREE
440 && obstack_empty_p (function_maybepermanent_obstack))
442 struct simple_obstack_stack *current, **p = &toplev_inline_obstacks;
446 while ((*p)->obstack != function_maybepermanent_obstack)
451 current->next = extra_inline_obstacks;
452 extra_inline_obstacks = current;
456 obstack_free (function_obstack, 0);
457 free (function_obstack);
459 temporary_firstobj = p->temporary_firstobj;
460 momentary_firstobj = p->momentary_firstobj;
461 momentary_function_firstobj = p->momentary_function_firstobj;
462 maybepermanent_firstobj = p->maybepermanent_firstobj;
463 function_obstack = p->function_obstack;
464 function_maybepermanent_obstack = p->function_maybepermanent_obstack;
465 current_obstack = p->current_obstack;
466 expression_obstack = p->expression_obstack;
467 saveable_obstack = p->saveable_obstack;
468 rtl_obstack = p->rtl_obstack;
469 inline_obstacks = p->inline_obstacks;
472 /* Start allocating on the temporary (per function) obstack.
473 This is done in start_function before parsing the function body,
474 and before each initialization at top level, and to go back
475 to temporary allocation after doing permanent_allocation. */
478 temporary_allocation ()
480 /* Note that function_obstack at top level points to temporary_obstack.
481 But within a nested function context, it is a separate obstack. */
482 current_obstack = function_obstack;
483 expression_obstack = function_obstack;
484 rtl_obstack = saveable_obstack = function_maybepermanent_obstack;
489 /* Start allocating on the permanent obstack but don't
490 free the temporary data. After calling this, call
491 `permanent_allocation' to fully resume permanent allocation status. */
494 end_temporary_allocation ()
496 current_obstack = &permanent_obstack;
497 expression_obstack = &permanent_obstack;
498 rtl_obstack = saveable_obstack = &permanent_obstack;
501 /* Resume allocating on the temporary obstack, undoing
502 effects of `end_temporary_allocation'. */
505 resume_temporary_allocation ()
507 current_obstack = function_obstack;
508 expression_obstack = function_obstack;
509 rtl_obstack = saveable_obstack = function_maybepermanent_obstack;
512 /* While doing temporary allocation, switch to allocating in such a
513 way as to save all nodes if the function is inlined. Call
514 resume_temporary_allocation to go back to ordinary temporary
518 saveable_allocation ()
520 /* Note that function_obstack at top level points to temporary_obstack.
521 But within a nested function context, it is a separate obstack. */
522 expression_obstack = current_obstack = saveable_obstack;
525 /* Switch to current obstack CURRENT and maybepermanent obstack SAVEABLE,
526 recording the previously current obstacks on a stack.
527 This does not free any storage in any obstack. */
530 push_obstacks (current, saveable)
531 struct obstack *current, *saveable;
533 struct obstack_stack *p
534 = (struct obstack_stack *) obstack_alloc (&obstack_stack_obstack,
535 (sizeof (struct obstack_stack)));
537 p->current = current_obstack;
538 p->saveable = saveable_obstack;
539 p->expression = expression_obstack;
540 p->rtl = rtl_obstack;
541 p->next = obstack_stack;
544 current_obstack = current;
545 expression_obstack = current;
546 rtl_obstack = saveable_obstack = saveable;
549 /* Save the current set of obstacks, but don't change them. */
552 push_obstacks_nochange ()
554 struct obstack_stack *p
555 = (struct obstack_stack *) obstack_alloc (&obstack_stack_obstack,
556 (sizeof (struct obstack_stack)));
558 p->current = current_obstack;
559 p->saveable = saveable_obstack;
560 p->expression = expression_obstack;
561 p->rtl = rtl_obstack;
562 p->next = obstack_stack;
566 /* Pop the obstack selection stack. */
571 struct obstack_stack *p = obstack_stack;
572 obstack_stack = p->next;
574 current_obstack = p->current;
575 saveable_obstack = p->saveable;
576 expression_obstack = p->expression;
577 rtl_obstack = p->rtl;
579 obstack_free (&obstack_stack_obstack, p);
582 /* Nonzero if temporary allocation is currently in effect.
583 Zero if currently doing permanent allocation. */
586 allocation_temporary_p ()
588 return current_obstack != &permanent_obstack;
591 /* Go back to allocating on the permanent obstack
592 and free everything in the temporary obstack.
594 FUNCTION_END is true only if we have just finished compiling a function.
595 In that case, we also free preserved initial values on the momentary
599 permanent_allocation (function_end)
602 /* Free up previous temporary obstack data */
603 obstack_free (&temporary_obstack, temporary_firstobj);
606 obstack_free (&momentary_obstack, momentary_function_firstobj);
607 momentary_firstobj = momentary_function_firstobj;
610 obstack_free (&momentary_obstack, momentary_firstobj);
611 obstack_free (function_maybepermanent_obstack, maybepermanent_firstobj);
612 obstack_free (&temp_decl_obstack, temp_decl_firstobj);
614 /* Free up the maybepermanent_obstacks for any of our nested functions
615 which were compiled at a lower level. */
616 while (inline_obstacks)
618 struct simple_obstack_stack *current = inline_obstacks;
619 inline_obstacks = current->next;
620 obstack_free (current->obstack, 0);
621 free (current->obstack);
625 current_obstack = &permanent_obstack;
626 expression_obstack = &permanent_obstack;
627 rtl_obstack = saveable_obstack = &permanent_obstack;
630 /* Save permanently everything on the maybepermanent_obstack. */
635 maybepermanent_firstobj
636 = (char *) obstack_alloc (function_maybepermanent_obstack, 0);
640 preserve_initializer ()
642 struct momentary_level *tem;
646 = (char *) obstack_alloc (&temporary_obstack, 0);
647 maybepermanent_firstobj
648 = (char *) obstack_alloc (function_maybepermanent_obstack, 0);
650 old_momentary = momentary_firstobj;
652 = (char *) obstack_alloc (&momentary_obstack, 0);
653 if (momentary_firstobj != old_momentary)
654 for (tem = momentary_stack; tem; tem = tem->prev)
655 tem->base = momentary_firstobj;
658 /* Start allocating new rtl in current_obstack.
659 Use resume_temporary_allocation
660 to go back to allocating rtl in saveable_obstack. */
663 rtl_in_current_obstack ()
665 rtl_obstack = current_obstack;
668 /* Start allocating rtl from saveable_obstack. Intended to be used after
669 a call to push_obstacks_nochange. */
672 rtl_in_saveable_obstack ()
674 rtl_obstack = saveable_obstack;
677 /* Allocate SIZE bytes in the current obstack
678 and return a pointer to them.
679 In practice the current obstack is always the temporary one. */
685 return (char *) obstack_alloc (current_obstack, size);
688 /* Free the object PTR in the current obstack
689 as well as everything allocated since PTR.
690 In practice the current obstack is always the temporary one. */
696 obstack_free (current_obstack, ptr);
699 /* Allocate SIZE bytes in the permanent obstack
700 and return a pointer to them. */
706 return (char *) obstack_alloc (&permanent_obstack, size);
709 /* Allocate NELEM items of SIZE bytes in the permanent obstack
710 and return a pointer to them. The storage is cleared before
711 returning the value. */
714 perm_calloc (nelem, size)
718 char *rval = (char *) obstack_alloc (&permanent_obstack, nelem * size);
719 bzero (rval, nelem * size);
723 /* Allocate SIZE bytes in the saveable obstack
724 and return a pointer to them. */
730 return (char *) obstack_alloc (saveable_obstack, size);
733 /* Allocate SIZE bytes in the expression obstack
734 and return a pointer to them. */
740 return (char *) obstack_alloc (expression_obstack, size);
743 /* Print out which obstack an object is in. */
746 print_obstack_name (object, file, prefix)
751 struct obstack *obstack = NULL;
752 const char *obstack_name = NULL;
755 for (p = outer_function_chain; p; p = p->next)
757 if (_obstack_allocated_p (p->function_obstack, object))
759 obstack = p->function_obstack;
760 obstack_name = "containing function obstack";
762 if (_obstack_allocated_p (p->function_maybepermanent_obstack, object))
764 obstack = p->function_maybepermanent_obstack;
765 obstack_name = "containing function maybepermanent obstack";
769 if (_obstack_allocated_p (&obstack_stack_obstack, object))
771 obstack = &obstack_stack_obstack;
772 obstack_name = "obstack_stack_obstack";
774 else if (_obstack_allocated_p (function_obstack, object))
776 obstack = function_obstack;
777 obstack_name = "function obstack";
779 else if (_obstack_allocated_p (&permanent_obstack, object))
781 obstack = &permanent_obstack;
782 obstack_name = "permanent_obstack";
784 else if (_obstack_allocated_p (&momentary_obstack, object))
786 obstack = &momentary_obstack;
787 obstack_name = "momentary_obstack";
789 else if (_obstack_allocated_p (function_maybepermanent_obstack, object))
791 obstack = function_maybepermanent_obstack;
792 obstack_name = "function maybepermanent obstack";
794 else if (_obstack_allocated_p (&temp_decl_obstack, object))
796 obstack = &temp_decl_obstack;
797 obstack_name = "temp_decl_obstack";
800 /* Check to see if the object is in the free area of the obstack. */
803 if (object >= obstack->next_free
804 && object < obstack->chunk_limit)
805 fprintf (file, "%s in free portion of obstack %s",
806 prefix, obstack_name);
808 fprintf (file, "%s allocated from %s", prefix, obstack_name);
811 fprintf (file, "%s not allocated from any obstack", prefix);
815 debug_obstack (object)
818 print_obstack_name (object, stderr, "object");
819 fprintf (stderr, ".\n");
822 /* Return 1 if OBJ is in the permanent obstack.
823 This is slow, and should be used only for debugging.
824 Use TREE_PERMANENT for other purposes. */
827 object_permanent_p (obj)
830 return _obstack_allocated_p (&permanent_obstack, obj);
833 /* Start a level of momentary allocation.
834 In C, each compound statement has its own level
835 and that level is freed at the end of each statement.
836 All expression nodes are allocated in the momentary allocation level. */
841 struct momentary_level *tem
842 = (struct momentary_level *) obstack_alloc (&momentary_obstack,
843 sizeof (struct momentary_level));
844 tem->prev = momentary_stack;
845 tem->base = (char *) obstack_base (&momentary_obstack);
846 tem->obstack = expression_obstack;
847 momentary_stack = tem;
848 expression_obstack = &momentary_obstack;
851 /* Set things up so the next clear_momentary will only clear memory
852 past our present position in momentary_obstack. */
855 preserve_momentary ()
857 momentary_stack->base = (char *) obstack_base (&momentary_obstack);
860 /* Free all the storage in the current momentary-allocation level.
861 In C, this happens at the end of each statement. */
866 obstack_free (&momentary_obstack, momentary_stack->base);
869 /* Discard a level of momentary allocation.
870 In C, this happens at the end of each compound statement.
871 Restore the status of expression node allocation
872 that was in effect before this level was created. */
877 struct momentary_level *tem = momentary_stack;
878 momentary_stack = tem->prev;
879 expression_obstack = tem->obstack;
880 /* We can't free TEM from the momentary_obstack, because there might
881 be objects above it which have been saved. We can free back to the
882 stack of the level we are popping off though. */
883 obstack_free (&momentary_obstack, tem->base);
886 /* Pop back to the previous level of momentary allocation,
887 but don't free any momentary data just yet. */
890 pop_momentary_nofree ()
892 struct momentary_level *tem = momentary_stack;
893 momentary_stack = tem->prev;
894 expression_obstack = tem->obstack;
897 /* Call when starting to parse a declaration:
898 make expressions in the declaration last the length of the function.
899 Returns an argument that should be passed to resume_momentary later. */
904 register int tem = expression_obstack == &momentary_obstack;
905 expression_obstack = saveable_obstack;
909 /* Call when finished parsing a declaration:
910 restore the treatment of node-allocation that was
911 in effect before the suspension.
912 YES should be the value previously returned by suspend_momentary. */
915 resume_momentary (yes)
919 expression_obstack = &momentary_obstack;
922 /* Init the tables indexed by tree code.
923 Note that languages can add to these tables to define their own codes. */
931 /* Return a newly allocated node of code CODE.
932 Initialize the node's unique id and its TREE_PERMANENT flag.
933 For decl and type nodes, some other fields are initialized.
934 The rest of the node is initialized to zero.
936 Achoo! I got a code in the node. */
943 register int type = TREE_CODE_CLASS (code);
944 register int length = 0;
945 register struct obstack *obstack = current_obstack;
946 #ifdef GATHER_STATISTICS
947 register tree_node_kind kind;
952 case 'd': /* A decl node */
953 #ifdef GATHER_STATISTICS
956 length = sizeof (struct tree_decl);
957 /* All decls in an inline function need to be saved. */
958 if (obstack != &permanent_obstack)
959 obstack = saveable_obstack;
961 /* PARM_DECLs go on the context of the parent. If this is a nested
962 function, then we must allocate the PARM_DECL on the parent's
963 obstack, so that they will live to the end of the parent's
964 closing brace. This is necessary in case we try to inline the
965 function into its parent.
967 PARM_DECLs of top-level functions do not have this problem. However,
968 we allocate them where we put the FUNCTION_DECL for languages such as
969 Ada that need to consult some flags in the PARM_DECLs of the function
972 See comment in restore_tree_status for why we can't put this
973 in function_obstack. */
974 if (code == PARM_DECL && obstack != &permanent_obstack)
977 if (current_function_decl)
978 context = decl_function_context (current_function_decl);
982 = find_function_data (context)->function_maybepermanent_obstack;
986 case 't': /* a type node */
987 #ifdef GATHER_STATISTICS
990 length = sizeof (struct tree_type);
991 /* All data types are put where we can preserve them if nec. */
992 if (obstack != &permanent_obstack)
993 obstack = all_types_permanent ? &permanent_obstack : saveable_obstack;
996 case 'b': /* a lexical block */
997 #ifdef GATHER_STATISTICS
1000 length = sizeof (struct tree_block);
1001 /* All BLOCK nodes are put where we can preserve them if nec. */
1002 if (obstack != &permanent_obstack)
1003 obstack = saveable_obstack;
1006 case 's': /* an expression with side effects */
1007 #ifdef GATHER_STATISTICS
1011 case 'r': /* a reference */
1012 #ifdef GATHER_STATISTICS
1016 case 'e': /* an expression */
1017 case '<': /* a comparison expression */
1018 case '1': /* a unary arithmetic expression */
1019 case '2': /* a binary arithmetic expression */
1020 #ifdef GATHER_STATISTICS
1024 obstack = expression_obstack;
1025 /* All BIND_EXPR nodes are put where we can preserve them if nec. */
1026 if (code == BIND_EXPR && obstack != &permanent_obstack)
1027 obstack = saveable_obstack;
1028 length = sizeof (struct tree_exp)
1029 + (tree_code_length[(int) code] - 1) * sizeof (char *);
1032 case 'c': /* a constant */
1033 #ifdef GATHER_STATISTICS
1036 obstack = expression_obstack;
1038 /* We can't use tree_code_length for INTEGER_CST, since the number of
1039 words is machine-dependent due to varying length of HOST_WIDE_INT,
1040 which might be wider than a pointer (e.g., long long). Similarly
1041 for REAL_CST, since the number of words is machine-dependent due
1042 to varying size and alignment of `double'. */
1044 if (code == INTEGER_CST)
1045 length = sizeof (struct tree_int_cst);
1046 else if (code == REAL_CST)
1047 length = sizeof (struct tree_real_cst);
1049 length = sizeof (struct tree_common)
1050 + tree_code_length[(int) code] * sizeof (char *);
1053 case 'x': /* something random, like an identifier. */
1054 #ifdef GATHER_STATISTICS
1055 if (code == IDENTIFIER_NODE)
1057 else if (code == OP_IDENTIFIER)
1059 else if (code == TREE_VEC)
1064 length = sizeof (struct tree_common)
1065 + tree_code_length[(int) code] * sizeof (char *);
1066 /* Identifier nodes are always permanent since they are
1067 unique in a compiler run. */
1068 if (code == IDENTIFIER_NODE) obstack = &permanent_obstack;
1075 t = (tree) obstack_alloc (obstack, length);
1076 bzero ((PTR) t, length);
1078 #ifdef GATHER_STATISTICS
1079 tree_node_counts[(int)kind]++;
1080 tree_node_sizes[(int)kind] += length;
1083 TREE_SET_CODE (t, code);
1084 if (obstack == &permanent_obstack)
1085 TREE_PERMANENT (t) = 1;
1090 TREE_SIDE_EFFECTS (t) = 1;
1091 TREE_TYPE (t) = void_type_node;
1095 if (code != FUNCTION_DECL)
1097 DECL_IN_SYSTEM_HEADER (t)
1098 = in_system_header && (obstack == &permanent_obstack);
1099 DECL_SOURCE_LINE (t) = lineno;
1100 DECL_SOURCE_FILE (t) = (input_filename) ? input_filename : "<built-in>";
1101 DECL_UID (t) = next_decl_uid++;
1102 /* Note that we have not yet computed the alias set for this
1104 DECL_POINTER_ALIAS_SET (t) = -1;
1108 TYPE_UID (t) = next_type_uid++;
1110 TYPE_MAIN_VARIANT (t) = t;
1111 TYPE_OBSTACK (t) = obstack;
1112 TYPE_ATTRIBUTES (t) = NULL_TREE;
1113 #ifdef SET_DEFAULT_TYPE_ATTRIBUTES
1114 SET_DEFAULT_TYPE_ATTRIBUTES (t);
1116 /* Note that we have not yet computed the alias set for this
1118 TYPE_ALIAS_SET (t) = -1;
1122 TREE_CONSTANT (t) = 1;
1129 /* Return a new node with the same contents as NODE
1130 except that its TREE_CHAIN is zero and it has a fresh uid. */
1137 register enum tree_code code = TREE_CODE (node);
1138 register int length = 0;
1140 switch (TREE_CODE_CLASS (code))
1142 case 'd': /* A decl node */
1143 length = sizeof (struct tree_decl);
1146 case 't': /* a type node */
1147 length = sizeof (struct tree_type);
1150 case 'b': /* a lexical block node */
1151 length = sizeof (struct tree_block);
1154 case 'r': /* a reference */
1155 case 'e': /* an expression */
1156 case 's': /* an expression with side effects */
1157 case '<': /* a comparison expression */
1158 case '1': /* a unary arithmetic expression */
1159 case '2': /* a binary arithmetic expression */
1160 length = sizeof (struct tree_exp)
1161 + (tree_code_length[(int) code] - 1) * sizeof (char *);
1164 case 'c': /* a constant */
1165 /* We can't use tree_code_length for INTEGER_CST, since the number of
1166 words is machine-dependent due to varying length of HOST_WIDE_INT,
1167 which might be wider than a pointer (e.g., long long). Similarly
1168 for REAL_CST, since the number of words is machine-dependent due
1169 to varying size and alignment of `double'. */
1170 if (code == INTEGER_CST)
1171 length = sizeof (struct tree_int_cst);
1172 else if (code == REAL_CST)
1173 length = sizeof (struct tree_real_cst);
1175 length = (sizeof (struct tree_common)
1176 + tree_code_length[(int) code] * sizeof (char *));
1179 case 'x': /* something random, like an identifier. */
1180 length = sizeof (struct tree_common)
1181 + tree_code_length[(int) code] * sizeof (char *);
1182 if (code == TREE_VEC)
1183 length += (TREE_VEC_LENGTH (node) - 1) * sizeof (char *);
1186 t = (tree) obstack_alloc (current_obstack, length);
1187 memcpy (t, node, length);
1189 /* EXPR_WITH_FILE_LOCATION must keep filename info stored in TREE_CHAIN */
1190 if (TREE_CODE (node) != EXPR_WITH_FILE_LOCATION)
1192 TREE_ASM_WRITTEN (t) = 0;
1194 if (TREE_CODE_CLASS (code) == 'd')
1195 DECL_UID (t) = next_decl_uid++;
1196 else if (TREE_CODE_CLASS (code) == 't')
1198 TYPE_UID (t) = next_type_uid++;
1199 TYPE_OBSTACK (t) = current_obstack;
1201 /* The following is so that the debug code for
1202 the copy is different from the original type.
1203 The two statements usually duplicate each other
1204 (because they clear fields of the same union),
1205 but the optimizer should catch that. */
1206 TYPE_SYMTAB_POINTER (t) = 0;
1207 TYPE_SYMTAB_ADDRESS (t) = 0;
1210 TREE_PERMANENT (t) = (current_obstack == &permanent_obstack);
1215 /* Return a copy of a chain of nodes, chained through the TREE_CHAIN field.
1216 For example, this can copy a list made of TREE_LIST nodes. */
1223 register tree prev, next;
1228 head = prev = copy_node (list);
1229 next = TREE_CHAIN (list);
1232 TREE_CHAIN (prev) = copy_node (next);
1233 prev = TREE_CHAIN (prev);
1234 next = TREE_CHAIN (next);
1241 /* Return an IDENTIFIER_NODE whose name is TEXT (a null-terminated string).
1242 If an identifier with that name has previously been referred to,
1243 the same node is returned this time. */
1246 get_identifier (text)
1247 register const char *text;
1252 register int len, hash_len;
1254 /* Compute length of text in len. */
1255 len = strlen (text);
1257 /* Decide how much of that length to hash on */
1259 if (warn_id_clash && (unsigned)len > id_clash_len)
1260 hash_len = id_clash_len;
1262 /* Compute hash code */
1263 hi = hash_len * 613 + (unsigned) text[0];
1264 for (i = 1; i < hash_len; i += 2)
1265 hi = ((hi * 613) + (unsigned) (text[i]));
1267 hi &= (1 << HASHBITS) - 1;
1268 hi %= MAX_HASH_TABLE;
1270 /* Search table for identifier */
1271 for (idp = hash_table[hi]; idp; idp = TREE_CHAIN (idp))
1272 if (IDENTIFIER_LENGTH (idp) == len
1273 && IDENTIFIER_POINTER (idp)[0] == text[0]
1274 && !bcmp (IDENTIFIER_POINTER (idp), text, len))
1275 return idp; /* <-- return if found */
1277 /* Not found; optionally warn about a similar identifier */
1278 if (warn_id_clash && do_identifier_warnings && (unsigned)len >= id_clash_len)
1279 for (idp = hash_table[hi]; idp; idp = TREE_CHAIN (idp))
1280 if (!strncmp (IDENTIFIER_POINTER (idp), text, id_clash_len))
1282 warning ("`%s' and `%s' identical in first %d characters",
1283 IDENTIFIER_POINTER (idp), text, id_clash_len);
1287 if (tree_code_length[(int) IDENTIFIER_NODE] < 0)
1288 abort (); /* set_identifier_size hasn't been called. */
1290 /* Not found, create one, add to chain */
1291 idp = make_node (IDENTIFIER_NODE);
1292 IDENTIFIER_LENGTH (idp) = len;
1293 #ifdef GATHER_STATISTICS
1294 id_string_size += len;
1297 IDENTIFIER_POINTER (idp) = obstack_copy0 (&permanent_obstack, text, len);
1299 TREE_CHAIN (idp) = hash_table[hi];
1300 hash_table[hi] = idp;
1301 return idp; /* <-- return if created */
1304 /* If an identifier with the name TEXT (a null-terminated string) has
1305 previously been referred to, return that node; otherwise return
1309 maybe_get_identifier (text)
1310 register const char *text;
1315 register int len, hash_len;
1317 /* Compute length of text in len. */
1318 len = strlen (text);
1320 /* Decide how much of that length to hash on */
1322 if (warn_id_clash && (unsigned)len > id_clash_len)
1323 hash_len = id_clash_len;
1325 /* Compute hash code */
1326 hi = hash_len * 613 + (unsigned) text[0];
1327 for (i = 1; i < hash_len; i += 2)
1328 hi = ((hi * 613) + (unsigned) (text[i]));
1330 hi &= (1 << HASHBITS) - 1;
1331 hi %= MAX_HASH_TABLE;
1333 /* Search table for identifier */
1334 for (idp = hash_table[hi]; idp; idp = TREE_CHAIN (idp))
1335 if (IDENTIFIER_LENGTH (idp) == len
1336 && IDENTIFIER_POINTER (idp)[0] == text[0]
1337 && !bcmp (IDENTIFIER_POINTER (idp), text, len))
1338 return idp; /* <-- return if found */
1343 /* Enable warnings on similar identifiers (if requested).
1344 Done after the built-in identifiers are created. */
1347 start_identifier_warnings ()
1349 do_identifier_warnings = 1;
1352 /* Record the size of an identifier node for the language in use.
1353 SIZE is the total size in bytes.
1354 This is called by the language-specific files. This must be
1355 called before allocating any identifiers. */
1358 set_identifier_size (size)
1361 tree_code_length[(int) IDENTIFIER_NODE]
1362 = (size - sizeof (struct tree_common)) / sizeof (tree);
1365 /* Return a newly constructed INTEGER_CST node whose constant value
1366 is specified by the two ints LOW and HI.
1367 The TREE_TYPE is set to `int'.
1369 This function should be used via the `build_int_2' macro. */
1372 build_int_2_wide (low, hi)
1373 HOST_WIDE_INT low, hi;
1375 register tree t = make_node (INTEGER_CST);
1376 TREE_INT_CST_LOW (t) = low;
1377 TREE_INT_CST_HIGH (t) = hi;
1378 TREE_TYPE (t) = integer_type_node;
1382 /* Return a new REAL_CST node whose type is TYPE and value is D. */
1385 build_real (type, d)
1392 /* Check for valid float value for this type on this target machine;
1393 if not, can print error message and store a valid value in D. */
1394 #ifdef CHECK_FLOAT_VALUE
1395 CHECK_FLOAT_VALUE (TYPE_MODE (type), d, overflow);
1398 v = make_node (REAL_CST);
1399 TREE_TYPE (v) = type;
1400 TREE_REAL_CST (v) = d;
1401 TREE_OVERFLOW (v) = TREE_CONSTANT_OVERFLOW (v) = overflow;
1405 /* Return a new REAL_CST node whose type is TYPE
1406 and whose value is the integer value of the INTEGER_CST node I. */
1408 #if !defined (REAL_IS_NOT_DOUBLE) || defined (REAL_ARITHMETIC)
1411 real_value_from_int_cst (type, i)
1416 #ifdef REAL_ARITHMETIC
1417 if (! TREE_UNSIGNED (TREE_TYPE (i)))
1418 REAL_VALUE_FROM_INT (d, TREE_INT_CST_LOW (i), TREE_INT_CST_HIGH (i),
1421 REAL_VALUE_FROM_UNSIGNED_INT (d, TREE_INT_CST_LOW (i),
1422 TREE_INT_CST_HIGH (i), TYPE_MODE (type));
1423 #else /* not REAL_ARITHMETIC */
1424 /* Some 386 compilers mishandle unsigned int to float conversions,
1425 so introduce a temporary variable E to avoid those bugs. */
1426 if (TREE_INT_CST_HIGH (i) < 0 && ! TREE_UNSIGNED (TREE_TYPE (i)))
1430 d = (double) (~ TREE_INT_CST_HIGH (i));
1431 e = ((double) ((HOST_WIDE_INT) 1 << (HOST_BITS_PER_WIDE_INT / 2))
1432 * (double) ((HOST_WIDE_INT) 1 << (HOST_BITS_PER_WIDE_INT / 2)));
1434 e = (double) (unsigned HOST_WIDE_INT) (~ TREE_INT_CST_LOW (i));
1442 d = (double) (unsigned HOST_WIDE_INT) TREE_INT_CST_HIGH (i);
1443 e = ((double) ((HOST_WIDE_INT) 1 << (HOST_BITS_PER_WIDE_INT / 2))
1444 * (double) ((HOST_WIDE_INT) 1 << (HOST_BITS_PER_WIDE_INT / 2)));
1446 e = (double) (unsigned HOST_WIDE_INT) TREE_INT_CST_LOW (i);
1449 #endif /* not REAL_ARITHMETIC */
1462 build_real_from_int_cst_1 (data)
1465 struct brfic_args * args = (struct brfic_args *) data;
1467 #ifdef REAL_ARITHMETIC
1468 args->d = real_value_from_int_cst (args->type, args->i);
1471 REAL_VALUE_TRUNCATE (TYPE_MODE (args->type),
1472 real_value_from_int_cst (args->type, args->i));
1476 /* This function can't be implemented if we can't do arithmetic
1477 on the float representation. */
1480 build_real_from_int_cst (type, i)
1485 int overflow = TREE_OVERFLOW (i);
1487 struct brfic_args args;
1489 v = make_node (REAL_CST);
1490 TREE_TYPE (v) = type;
1492 /* Setup input for build_real_from_int_cst_1() */
1496 if (do_float_handler (build_real_from_int_cst_1, (PTR) &args))
1498 /* Receive output from build_real_from_int_cst_1() */
1503 /* We got an exception from build_real_from_int_cst_1() */
1508 /* Check for valid float value for this type on this target machine. */
1510 #ifdef CHECK_FLOAT_VALUE
1511 CHECK_FLOAT_VALUE (TYPE_MODE (type), d, overflow);
1514 TREE_REAL_CST (v) = d;
1515 TREE_OVERFLOW (v) = TREE_CONSTANT_OVERFLOW (v) = overflow;
1519 #endif /* not REAL_IS_NOT_DOUBLE, or REAL_ARITHMETIC */
1521 /* Return a newly constructed STRING_CST node whose value is
1522 the LEN characters at STR.
1523 The TREE_TYPE is not initialized. */
1526 build_string (len, str)
1530 /* Put the string in saveable_obstack since it will be placed in the RTL
1531 for an "asm" statement and will also be kept around a while if
1532 deferring constant output in varasm.c. */
1534 register tree s = make_node (STRING_CST);
1535 TREE_STRING_LENGTH (s) = len;
1536 TREE_STRING_POINTER (s) = obstack_copy0 (saveable_obstack, str, len);
1540 /* Return a newly constructed COMPLEX_CST node whose value is
1541 specified by the real and imaginary parts REAL and IMAG.
1542 Both REAL and IMAG should be constant nodes. TYPE, if specified,
1543 will be the type of the COMPLEX_CST; otherwise a new type will be made. */
1546 build_complex (type, real, imag)
1550 register tree t = make_node (COMPLEX_CST);
1552 TREE_REALPART (t) = real;
1553 TREE_IMAGPART (t) = imag;
1554 TREE_TYPE (t) = type ? type : build_complex_type (TREE_TYPE (real));
1555 TREE_OVERFLOW (t) = TREE_OVERFLOW (real) | TREE_OVERFLOW (imag);
1556 TREE_CONSTANT_OVERFLOW (t)
1557 = TREE_CONSTANT_OVERFLOW (real) | TREE_CONSTANT_OVERFLOW (imag);
1561 /* Build a newly constructed TREE_VEC node of length LEN. */
1568 register int length = (len-1) * sizeof (tree) + sizeof (struct tree_vec);
1569 register struct obstack *obstack = current_obstack;
1571 #ifdef GATHER_STATISTICS
1572 tree_node_counts[(int)vec_kind]++;
1573 tree_node_sizes[(int)vec_kind] += length;
1576 t = (tree) obstack_alloc (obstack, length);
1577 bzero ((PTR) t, length);
1579 TREE_SET_CODE (t, TREE_VEC);
1580 TREE_VEC_LENGTH (t) = len;
1581 if (obstack == &permanent_obstack)
1582 TREE_PERMANENT (t) = 1;
1587 /* Return 1 if EXPR is the integer constant zero or a complex constant
1591 integer_zerop (expr)
1596 return ((TREE_CODE (expr) == INTEGER_CST
1597 && ! TREE_CONSTANT_OVERFLOW (expr)
1598 && TREE_INT_CST_LOW (expr) == 0
1599 && TREE_INT_CST_HIGH (expr) == 0)
1600 || (TREE_CODE (expr) == COMPLEX_CST
1601 && integer_zerop (TREE_REALPART (expr))
1602 && integer_zerop (TREE_IMAGPART (expr))));
1605 /* Return 1 if EXPR is the integer constant one or the corresponding
1606 complex constant. */
1614 return ((TREE_CODE (expr) == INTEGER_CST
1615 && ! TREE_CONSTANT_OVERFLOW (expr)
1616 && TREE_INT_CST_LOW (expr) == 1
1617 && TREE_INT_CST_HIGH (expr) == 0)
1618 || (TREE_CODE (expr) == COMPLEX_CST
1619 && integer_onep (TREE_REALPART (expr))
1620 && integer_zerop (TREE_IMAGPART (expr))));
1623 /* Return 1 if EXPR is an integer containing all 1's in as much precision as
1624 it contains. Likewise for the corresponding complex constant. */
1627 integer_all_onesp (expr)
1635 if (TREE_CODE (expr) == COMPLEX_CST
1636 && integer_all_onesp (TREE_REALPART (expr))
1637 && integer_zerop (TREE_IMAGPART (expr)))
1640 else if (TREE_CODE (expr) != INTEGER_CST
1641 || TREE_CONSTANT_OVERFLOW (expr))
1644 uns = TREE_UNSIGNED (TREE_TYPE (expr));
1646 return TREE_INT_CST_LOW (expr) == -1 && TREE_INT_CST_HIGH (expr) == -1;
1648 /* Note that using TYPE_PRECISION here is wrong. We care about the
1649 actual bits, not the (arbitrary) range of the type. */
1650 prec = GET_MODE_BITSIZE (TYPE_MODE (TREE_TYPE (expr)));
1651 if (prec >= HOST_BITS_PER_WIDE_INT)
1653 int high_value, shift_amount;
1655 shift_amount = prec - HOST_BITS_PER_WIDE_INT;
1657 if (shift_amount > HOST_BITS_PER_WIDE_INT)
1658 /* Can not handle precisions greater than twice the host int size. */
1660 else if (shift_amount == HOST_BITS_PER_WIDE_INT)
1661 /* Shifting by the host word size is undefined according to the ANSI
1662 standard, so we must handle this as a special case. */
1665 high_value = ((HOST_WIDE_INT) 1 << shift_amount) - 1;
1667 return TREE_INT_CST_LOW (expr) == -1
1668 && TREE_INT_CST_HIGH (expr) == high_value;
1671 return TREE_INT_CST_LOW (expr) == ((HOST_WIDE_INT) 1 << prec) - 1;
1674 /* Return 1 if EXPR is an integer constant that is a power of 2 (i.e., has only
1678 integer_pow2p (expr)
1682 HOST_WIDE_INT high, low;
1686 if (TREE_CODE (expr) == COMPLEX_CST
1687 && integer_pow2p (TREE_REALPART (expr))
1688 && integer_zerop (TREE_IMAGPART (expr)))
1691 if (TREE_CODE (expr) != INTEGER_CST || TREE_CONSTANT_OVERFLOW (expr))
1694 prec = (POINTER_TYPE_P (TREE_TYPE (expr))
1695 ? POINTER_SIZE : TYPE_PRECISION (TREE_TYPE (expr)));
1696 high = TREE_INT_CST_HIGH (expr);
1697 low = TREE_INT_CST_LOW (expr);
1699 /* First clear all bits that are beyond the type's precision in case
1700 we've been sign extended. */
1702 if (prec == 2 * HOST_BITS_PER_WIDE_INT)
1704 else if (prec > HOST_BITS_PER_WIDE_INT)
1705 high &= ~((HOST_WIDE_INT) (-1) << (prec - HOST_BITS_PER_WIDE_INT));
1709 if (prec < HOST_BITS_PER_WIDE_INT)
1710 low &= ~((HOST_WIDE_INT) (-1) << prec);
1713 if (high == 0 && low == 0)
1716 return ((high == 0 && (low & (low - 1)) == 0)
1717 || (low == 0 && (high & (high - 1)) == 0));
1720 /* Return the power of two represented by a tree node known to be a
1728 HOST_WIDE_INT high, low;
1732 if (TREE_CODE (expr) == COMPLEX_CST)
1733 return tree_log2 (TREE_REALPART (expr));
1735 prec = (POINTER_TYPE_P (TREE_TYPE (expr))
1736 ? POINTER_SIZE : TYPE_PRECISION (TREE_TYPE (expr)));
1738 high = TREE_INT_CST_HIGH (expr);
1739 low = TREE_INT_CST_LOW (expr);
1741 /* First clear all bits that are beyond the type's precision in case
1742 we've been sign extended. */
1744 if (prec == 2 * HOST_BITS_PER_WIDE_INT)
1746 else if (prec > HOST_BITS_PER_WIDE_INT)
1747 high &= ~((HOST_WIDE_INT) (-1) << (prec - HOST_BITS_PER_WIDE_INT));
1751 if (prec < HOST_BITS_PER_WIDE_INT)
1752 low &= ~((HOST_WIDE_INT) (-1) << prec);
1755 return (high != 0 ? HOST_BITS_PER_WIDE_INT + exact_log2 (high)
1756 : exact_log2 (low));
1759 /* Return 1 if EXPR is the real constant zero. */
1767 return ((TREE_CODE (expr) == REAL_CST
1768 && ! TREE_CONSTANT_OVERFLOW (expr)
1769 && REAL_VALUES_EQUAL (TREE_REAL_CST (expr), dconst0))
1770 || (TREE_CODE (expr) == COMPLEX_CST
1771 && real_zerop (TREE_REALPART (expr))
1772 && real_zerop (TREE_IMAGPART (expr))));
1775 /* Return 1 if EXPR is the real constant one in real or complex form. */
1783 return ((TREE_CODE (expr) == REAL_CST
1784 && ! TREE_CONSTANT_OVERFLOW (expr)
1785 && REAL_VALUES_EQUAL (TREE_REAL_CST (expr), dconst1))
1786 || (TREE_CODE (expr) == COMPLEX_CST
1787 && real_onep (TREE_REALPART (expr))
1788 && real_zerop (TREE_IMAGPART (expr))));
1791 /* Return 1 if EXPR is the real constant two. */
1799 return ((TREE_CODE (expr) == REAL_CST
1800 && ! TREE_CONSTANT_OVERFLOW (expr)
1801 && REAL_VALUES_EQUAL (TREE_REAL_CST (expr), dconst2))
1802 || (TREE_CODE (expr) == COMPLEX_CST
1803 && real_twop (TREE_REALPART (expr))
1804 && real_zerop (TREE_IMAGPART (expr))));
1807 /* Nonzero if EXP is a constant or a cast of a constant. */
1810 really_constant_p (exp)
1813 /* This is not quite the same as STRIP_NOPS. It does more. */
1814 while (TREE_CODE (exp) == NOP_EXPR
1815 || TREE_CODE (exp) == CONVERT_EXPR
1816 || TREE_CODE (exp) == NON_LVALUE_EXPR)
1817 exp = TREE_OPERAND (exp, 0);
1818 return TREE_CONSTANT (exp);
1821 /* Return first list element whose TREE_VALUE is ELEM.
1822 Return 0 if ELEM is not in LIST. */
1825 value_member (elem, list)
1830 if (elem == TREE_VALUE (list))
1832 list = TREE_CHAIN (list);
1837 /* Return first list element whose TREE_PURPOSE is ELEM.
1838 Return 0 if ELEM is not in LIST. */
1841 purpose_member (elem, list)
1846 if (elem == TREE_PURPOSE (list))
1848 list = TREE_CHAIN (list);
1853 /* Return first list element whose BINFO_TYPE is ELEM.
1854 Return 0 if ELEM is not in LIST. */
1857 binfo_member (elem, list)
1862 if (elem == BINFO_TYPE (list))
1864 list = TREE_CHAIN (list);
1869 /* Return nonzero if ELEM is part of the chain CHAIN. */
1872 chain_member (elem, chain)
1879 chain = TREE_CHAIN (chain);
1885 /* Return nonzero if ELEM is equal to TREE_VALUE (CHAIN) for any piece of
1887 /* ??? This function was added for machine specific attributes but is no
1888 longer used. It could be deleted if we could confirm all front ends
1892 chain_member_value (elem, chain)
1897 if (elem == TREE_VALUE (chain))
1899 chain = TREE_CHAIN (chain);
1905 /* Return nonzero if ELEM is equal to TREE_PURPOSE (CHAIN)
1906 for any piece of chain CHAIN. */
1907 /* ??? This function was added for machine specific attributes but is no
1908 longer used. It could be deleted if we could confirm all front ends
1912 chain_member_purpose (elem, chain)
1917 if (elem == TREE_PURPOSE (chain))
1919 chain = TREE_CHAIN (chain);
1925 /* Return the length of a chain of nodes chained through TREE_CHAIN.
1926 We expect a null pointer to mark the end of the chain.
1927 This is the Lisp primitive `length'. */
1934 register int len = 0;
1936 for (tail = t; tail; tail = TREE_CHAIN (tail))
1942 /* Concatenate two chains of nodes (chained through TREE_CHAIN)
1943 by modifying the last node in chain 1 to point to chain 2.
1944 This is the Lisp primitive `nconc'. */
1956 for (t1 = op1; TREE_CHAIN (t1); t1 = TREE_CHAIN (t1))
1958 TREE_CHAIN (t1) = op2;
1959 #ifdef ENABLE_CHECKING
1960 for (t2 = op2; t2; t2 = TREE_CHAIN (t2))
1962 abort (); /* Circularity created. */
1969 /* Return the last node in a chain of nodes (chained through TREE_CHAIN). */
1973 register tree chain;
1977 while ((next = TREE_CHAIN (chain)))
1982 /* Reverse the order of elements in the chain T,
1983 and return the new head of the chain (old last element). */
1989 register tree prev = 0, decl, next;
1990 for (decl = t; decl; decl = next)
1992 next = TREE_CHAIN (decl);
1993 TREE_CHAIN (decl) = prev;
1999 /* Given a chain CHAIN of tree nodes,
2000 construct and return a list of those nodes. */
2006 tree result = NULL_TREE;
2007 tree in_tail = chain;
2008 tree out_tail = NULL_TREE;
2012 tree next = tree_cons (NULL_TREE, in_tail, NULL_TREE);
2014 TREE_CHAIN (out_tail) = next;
2018 in_tail = TREE_CHAIN (in_tail);
2024 /* Return a newly created TREE_LIST node whose
2025 purpose and value fields are PARM and VALUE. */
2028 build_tree_list (parm, value)
2031 register tree t = make_node (TREE_LIST);
2032 TREE_PURPOSE (t) = parm;
2033 TREE_VALUE (t) = value;
2037 /* Similar, but build on the temp_decl_obstack. */
2040 build_decl_list (parm, value)
2044 register struct obstack *ambient_obstack = current_obstack;
2045 current_obstack = &temp_decl_obstack;
2046 node = build_tree_list (parm, value);
2047 current_obstack = ambient_obstack;
2051 /* Similar, but build on the expression_obstack. */
2054 build_expr_list (parm, value)
2058 register struct obstack *ambient_obstack = current_obstack;
2059 current_obstack = expression_obstack;
2060 node = build_tree_list (parm, value);
2061 current_obstack = ambient_obstack;
2065 /* Return a newly created TREE_LIST node whose
2066 purpose and value fields are PARM and VALUE
2067 and whose TREE_CHAIN is CHAIN. */
2070 tree_cons (purpose, value, chain)
2071 tree purpose, value, chain;
2074 register tree node = make_node (TREE_LIST);
2077 register tree node = (tree) obstack_alloc (current_obstack, sizeof (struct tree_list));
2078 #ifdef GATHER_STATISTICS
2079 tree_node_counts[(int)x_kind]++;
2080 tree_node_sizes[(int)x_kind] += sizeof (struct tree_list);
2083 for (i = (sizeof (struct tree_common) / sizeof (int)) - 1; i >= 0; i--)
2084 ((int *) node)[i] = 0;
2086 TREE_SET_CODE (node, TREE_LIST);
2087 if (current_obstack == &permanent_obstack)
2088 TREE_PERMANENT (node) = 1;
2091 TREE_CHAIN (node) = chain;
2092 TREE_PURPOSE (node) = purpose;
2093 TREE_VALUE (node) = value;
2097 /* Similar, but build on the temp_decl_obstack. */
2100 decl_tree_cons (purpose, value, chain)
2101 tree purpose, value, chain;
2104 register struct obstack *ambient_obstack = current_obstack;
2105 current_obstack = &temp_decl_obstack;
2106 node = tree_cons (purpose, value, chain);
2107 current_obstack = ambient_obstack;
2111 /* Similar, but build on the expression_obstack. */
2114 expr_tree_cons (purpose, value, chain)
2115 tree purpose, value, chain;
2118 register struct obstack *ambient_obstack = current_obstack;
2119 current_obstack = expression_obstack;
2120 node = tree_cons (purpose, value, chain);
2121 current_obstack = ambient_obstack;
2125 /* Same as `tree_cons' but make a permanent object. */
2128 perm_tree_cons (purpose, value, chain)
2129 tree purpose, value, chain;
2132 register struct obstack *ambient_obstack = current_obstack;
2133 current_obstack = &permanent_obstack;
2135 node = tree_cons (purpose, value, chain);
2136 current_obstack = ambient_obstack;
2140 /* Same as `tree_cons', but make this node temporary, regardless. */
2143 temp_tree_cons (purpose, value, chain)
2144 tree purpose, value, chain;
2147 register struct obstack *ambient_obstack = current_obstack;
2148 current_obstack = &temporary_obstack;
2150 node = tree_cons (purpose, value, chain);
2151 current_obstack = ambient_obstack;
2155 /* Same as `tree_cons', but save this node if the function's RTL is saved. */
2158 saveable_tree_cons (purpose, value, chain)
2159 tree purpose, value, chain;
2162 register struct obstack *ambient_obstack = current_obstack;
2163 current_obstack = saveable_obstack;
2165 node = tree_cons (purpose, value, chain);
2166 current_obstack = ambient_obstack;
2170 /* Return the size nominally occupied by an object of type TYPE
2171 when it resides in memory. The value is measured in units of bytes,
2172 and its data type is that normally used for type sizes
2173 (which is the first type created by make_signed_type or
2174 make_unsigned_type). */
2177 size_in_bytes (type)
2182 if (type == error_mark_node)
2183 return integer_zero_node;
2185 type = TYPE_MAIN_VARIANT (type);
2186 t = TYPE_SIZE_UNIT (type);
2189 incomplete_type_error (NULL_TREE, type);
2190 return integer_zero_node;
2192 if (TREE_CODE (t) == INTEGER_CST)
2193 force_fit_type (t, 0);
2198 /* Return the size of TYPE (in bytes) as a wide integer
2199 or return -1 if the size can vary or is larger than an integer. */
2202 int_size_in_bytes (type)
2207 if (type == error_mark_node)
2210 type = TYPE_MAIN_VARIANT (type);
2211 t = TYPE_SIZE_UNIT (type);
2213 || TREE_CODE (t) != INTEGER_CST
2214 || TREE_INT_CST_HIGH (t) != 0)
2217 return TREE_INT_CST_LOW (t);
2220 /* Return, as a tree node, the number of elements for TYPE (which is an
2221 ARRAY_TYPE) minus one. This counts only elements of the top array.
2223 Don't let any SAVE_EXPRs escape; if we are called as part of a cleanup
2224 action, they would get unsaved. */
2227 array_type_nelts (type)
2230 tree index_type, min, max;
2232 /* If they did it with unspecified bounds, then we should have already
2233 given an error about it before we got here. */
2234 if (! TYPE_DOMAIN (type))
2235 return error_mark_node;
2237 index_type = TYPE_DOMAIN (type);
2238 min = TYPE_MIN_VALUE (index_type);
2239 max = TYPE_MAX_VALUE (index_type);
2241 if (! TREE_CONSTANT (min))
2244 if (TREE_CODE (min) == SAVE_EXPR)
2245 min = build (RTL_EXPR, TREE_TYPE (TYPE_MIN_VALUE (index_type)), 0,
2246 SAVE_EXPR_RTL (min));
2248 min = TYPE_MIN_VALUE (index_type);
2251 if (! TREE_CONSTANT (max))
2254 if (TREE_CODE (max) == SAVE_EXPR)
2255 max = build (RTL_EXPR, TREE_TYPE (TYPE_MAX_VALUE (index_type)), 0,
2256 SAVE_EXPR_RTL (max));
2258 max = TYPE_MAX_VALUE (index_type);
2261 return (integer_zerop (min)
2263 : fold (build (MINUS_EXPR, TREE_TYPE (max), max, min)));
2266 /* Return nonzero if arg is static -- a reference to an object in
2267 static storage. This is not the same as the C meaning of `static'. */
2273 switch (TREE_CODE (arg))
2276 /* Nested functions aren't static, since taking their address
2277 involves a trampoline. */
2278 return (decl_function_context (arg) == 0 || DECL_NO_STATIC_CHAIN (arg))
2279 && ! DECL_NON_ADDR_CONST_P (arg);
2282 return (TREE_STATIC (arg) || DECL_EXTERNAL (arg))
2283 && ! DECL_NON_ADDR_CONST_P (arg);
2286 return TREE_STATIC (arg);
2291 /* If we are referencing a bitfield, we can't evaluate an
2292 ADDR_EXPR at compile time and so it isn't a constant. */
2294 return (! DECL_BIT_FIELD (TREE_OPERAND (arg, 1))
2295 && staticp (TREE_OPERAND (arg, 0)));
2301 /* This case is technically correct, but results in setting
2302 TREE_CONSTANT on ADDR_EXPRs that cannot be evaluated at
2305 return TREE_CONSTANT (TREE_OPERAND (arg, 0));
2309 if (TREE_CODE (TYPE_SIZE (TREE_TYPE (arg))) == INTEGER_CST
2310 && TREE_CODE (TREE_OPERAND (arg, 1)) == INTEGER_CST)
2311 return staticp (TREE_OPERAND (arg, 0));
2318 /* Wrap a SAVE_EXPR around EXPR, if appropriate.
2319 Do this to any expression which may be used in more than one place,
2320 but must be evaluated only once.
2322 Normally, expand_expr would reevaluate the expression each time.
2323 Calling save_expr produces something that is evaluated and recorded
2324 the first time expand_expr is called on it. Subsequent calls to
2325 expand_expr just reuse the recorded value.
2327 The call to expand_expr that generates code that actually computes
2328 the value is the first call *at compile time*. Subsequent calls
2329 *at compile time* generate code to use the saved value.
2330 This produces correct result provided that *at run time* control
2331 always flows through the insns made by the first expand_expr
2332 before reaching the other places where the save_expr was evaluated.
2333 You, the caller of save_expr, must make sure this is so.
2335 Constants, and certain read-only nodes, are returned with no
2336 SAVE_EXPR because that is safe. Expressions containing placeholders
2337 are not touched; see tree.def for an explanation of what these
2344 register tree t = fold (expr);
2346 /* We don't care about whether this can be used as an lvalue in this
2348 while (TREE_CODE (t) == NON_LVALUE_EXPR)
2349 t = TREE_OPERAND (t, 0);
2351 /* If the tree evaluates to a constant, then we don't want to hide that
2352 fact (i.e. this allows further folding, and direct checks for constants).
2353 However, a read-only object that has side effects cannot be bypassed.
2354 Since it is no problem to reevaluate literals, we just return the
2357 if (TREE_CONSTANT (t) || (TREE_READONLY (t) && ! TREE_SIDE_EFFECTS (t))
2358 || TREE_CODE (t) == SAVE_EXPR || TREE_CODE (t) == ERROR_MARK)
2361 /* If T contains a PLACEHOLDER_EXPR, we must evaluate it each time, since
2362 it means that the size or offset of some field of an object depends on
2363 the value within another field.
2365 Note that it must not be the case that T contains both a PLACEHOLDER_EXPR
2366 and some variable since it would then need to be both evaluated once and
2367 evaluated more than once. Front-ends must assure this case cannot
2368 happen by surrounding any such subexpressions in their own SAVE_EXPR
2369 and forcing evaluation at the proper time. */
2370 if (contains_placeholder_p (t))
2373 t = build (SAVE_EXPR, TREE_TYPE (expr), t, current_function_decl, NULL_TREE);
2375 /* This expression might be placed ahead of a jump to ensure that the
2376 value was computed on both sides of the jump. So make sure it isn't
2377 eliminated as dead. */
2378 TREE_SIDE_EFFECTS (t) = 1;
2382 /* Arrange for an expression to be expanded multiple independent
2383 times. This is useful for cleanup actions, as the backend can
2384 expand them multiple times in different places. */
2392 /* If this is already protected, no sense in protecting it again. */
2393 if (TREE_CODE (expr) == UNSAVE_EXPR)
2396 t = build1 (UNSAVE_EXPR, TREE_TYPE (expr), expr);
2397 TREE_SIDE_EFFECTS (t) = TREE_SIDE_EFFECTS (expr);
2401 /* Returns the index of the first non-tree operand for CODE, or the number
2402 of operands if all are trees. */
2406 enum tree_code code;
2412 case GOTO_SUBROUTINE_EXPR:
2417 case WITH_CLEANUP_EXPR:
2418 /* Should be defined to be 2. */
2420 case METHOD_CALL_EXPR:
2423 return tree_code_length [(int) code];
2427 /* Modify a tree in place so that all the evaluate only once things
2428 are cleared out. Return the EXPR given. */
2431 unsave_expr_now (expr)
2434 enum tree_code code;
2438 if (expr == NULL_TREE)
2441 code = TREE_CODE (expr);
2442 first_rtl = first_rtl_op (code);
2446 SAVE_EXPR_RTL (expr) = 0;
2450 TREE_OPERAND (expr, 1) = TREE_OPERAND (expr, 3);
2451 TREE_OPERAND (expr, 3) = NULL_TREE;
2455 /* I don't yet know how to emit a sequence multiple times. */
2456 if (RTL_EXPR_SEQUENCE (expr) != 0)
2461 CALL_EXPR_RTL (expr) = 0;
2462 if (TREE_OPERAND (expr, 1)
2463 && TREE_CODE (TREE_OPERAND (expr, 1)) == TREE_LIST)
2465 tree exp = TREE_OPERAND (expr, 1);
2468 unsave_expr_now (TREE_VALUE (exp));
2469 exp = TREE_CHAIN (exp);
2478 switch (TREE_CODE_CLASS (code))
2480 case 'c': /* a constant */
2481 case 't': /* a type node */
2482 case 'x': /* something random, like an identifier or an ERROR_MARK. */
2483 case 'd': /* A decl node */
2484 case 'b': /* A block node */
2487 case 'e': /* an expression */
2488 case 'r': /* a reference */
2489 case 's': /* an expression with side effects */
2490 case '<': /* a comparison expression */
2491 case '2': /* a binary arithmetic expression */
2492 case '1': /* a unary arithmetic expression */
2493 for (i = first_rtl - 1; i >= 0; i--)
2494 unsave_expr_now (TREE_OPERAND (expr, i));
2502 /* Return 1 if EXP contains a PLACEHOLDER_EXPR; i.e., if it represents a size
2503 or offset that depends on a field within a record. */
2506 contains_placeholder_p (exp)
2509 register enum tree_code code = TREE_CODE (exp);
2512 /* If we have a WITH_RECORD_EXPR, it "cancels" any PLACEHOLDER_EXPR
2513 in it since it is supplying a value for it. */
2514 if (code == WITH_RECORD_EXPR)
2516 else if (code == PLACEHOLDER_EXPR)
2519 switch (TREE_CODE_CLASS (code))
2522 /* Don't look at any PLACEHOLDER_EXPRs that might be in index or bit
2523 position computations since they will be converted into a
2524 WITH_RECORD_EXPR involving the reference, which will assume
2525 here will be valid. */
2526 return contains_placeholder_p (TREE_OPERAND (exp, 0));
2529 if (code == TREE_LIST)
2530 return (contains_placeholder_p (TREE_VALUE (exp))
2531 || (TREE_CHAIN (exp) != 0
2532 && contains_placeholder_p (TREE_CHAIN (exp))));
2541 /* Ignoring the first operand isn't quite right, but works best. */
2542 return contains_placeholder_p (TREE_OPERAND (exp, 1));
2549 return (contains_placeholder_p (TREE_OPERAND (exp, 0))
2550 || contains_placeholder_p (TREE_OPERAND (exp, 1))
2551 || contains_placeholder_p (TREE_OPERAND (exp, 2)));
2554 /* If we already know this doesn't have a placeholder, don't
2556 if (SAVE_EXPR_NOPLACEHOLDER (exp) || SAVE_EXPR_RTL (exp) != 0)
2559 SAVE_EXPR_NOPLACEHOLDER (exp) = 1;
2560 result = contains_placeholder_p (TREE_OPERAND (exp, 0));
2562 SAVE_EXPR_NOPLACEHOLDER (exp) = 0;
2567 return (TREE_OPERAND (exp, 1) != 0
2568 && contains_placeholder_p (TREE_OPERAND (exp, 1)));
2574 switch (tree_code_length[(int) code])
2577 return contains_placeholder_p (TREE_OPERAND (exp, 0));
2579 return (contains_placeholder_p (TREE_OPERAND (exp, 0))
2580 || contains_placeholder_p (TREE_OPERAND (exp, 1)));
2591 /* Return 1 if EXP contains any expressions that produce cleanups for an
2592 outer scope to deal with. Used by fold. */
2600 if (! TREE_SIDE_EFFECTS (exp))
2603 switch (TREE_CODE (exp))
2606 case GOTO_SUBROUTINE_EXPR:
2607 case WITH_CLEANUP_EXPR:
2610 case CLEANUP_POINT_EXPR:
2614 for (exp = TREE_OPERAND (exp, 1); exp; exp = TREE_CHAIN (exp))
2616 cmp = has_cleanups (TREE_VALUE (exp));
2626 /* This general rule works for most tree codes. All exceptions should be
2627 handled above. If this is a language-specific tree code, we can't
2628 trust what might be in the operand, so say we don't know
2630 if ((int) TREE_CODE (exp) >= (int) LAST_AND_UNUSED_TREE_CODE)
2633 nops = first_rtl_op (TREE_CODE (exp));
2634 for (i = 0; i < nops; i++)
2635 if (TREE_OPERAND (exp, i) != 0)
2637 int type = TREE_CODE_CLASS (TREE_CODE (TREE_OPERAND (exp, i)));
2638 if (type == 'e' || type == '<' || type == '1' || type == '2'
2639 || type == 'r' || type == 's')
2641 cmp = has_cleanups (TREE_OPERAND (exp, i));
2650 /* Given a tree EXP, a FIELD_DECL F, and a replacement value R,
2651 return a tree with all occurrences of references to F in a
2652 PLACEHOLDER_EXPR replaced by R. Note that we assume here that EXP
2653 contains only arithmetic expressions or a CALL_EXPR with a
2654 PLACEHOLDER_EXPR occurring only in its arglist. */
2657 substitute_in_expr (exp, f, r)
2662 enum tree_code code = TREE_CODE (exp);
2667 switch (TREE_CODE_CLASS (code))
2674 if (code == PLACEHOLDER_EXPR)
2676 else if (code == TREE_LIST)
2678 op0 = (TREE_CHAIN (exp) == 0
2679 ? 0 : substitute_in_expr (TREE_CHAIN (exp), f, r));
2680 op1 = substitute_in_expr (TREE_VALUE (exp), f, r);
2681 if (op0 == TREE_CHAIN (exp) && op1 == TREE_VALUE (exp))
2684 return tree_cons (TREE_PURPOSE (exp), op1, op0);
2693 switch (tree_code_length[(int) code])
2696 op0 = substitute_in_expr (TREE_OPERAND (exp, 0), f, r);
2697 if (op0 == TREE_OPERAND (exp, 0))
2700 new = fold (build1 (code, TREE_TYPE (exp), op0));
2704 /* An RTL_EXPR cannot contain a PLACEHOLDER_EXPR; a CONSTRUCTOR
2705 could, but we don't support it. */
2706 if (code == RTL_EXPR)
2708 else if (code == CONSTRUCTOR)
2711 op0 = substitute_in_expr (TREE_OPERAND (exp, 0), f, r);
2712 op1 = substitute_in_expr (TREE_OPERAND (exp, 1), f, r);
2713 if (op0 == TREE_OPERAND (exp, 0) && op1 == TREE_OPERAND (exp, 1))
2716 new = fold (build (code, TREE_TYPE (exp), op0, op1));
2720 /* It cannot be that anything inside a SAVE_EXPR contains a
2721 PLACEHOLDER_EXPR. */
2722 if (code == SAVE_EXPR)
2725 else if (code == CALL_EXPR)
2727 op1 = substitute_in_expr (TREE_OPERAND (exp, 1), f, r);
2728 if (op1 == TREE_OPERAND (exp, 1))
2731 return build (code, TREE_TYPE (exp),
2732 TREE_OPERAND (exp, 0), op1, NULL_TREE);
2735 else if (code != COND_EXPR)
2738 op0 = substitute_in_expr (TREE_OPERAND (exp, 0), f, r);
2739 op1 = substitute_in_expr (TREE_OPERAND (exp, 1), f, r);
2740 op2 = substitute_in_expr (TREE_OPERAND (exp, 2), f, r);
2741 if (op0 == TREE_OPERAND (exp, 0) && op1 == TREE_OPERAND (exp, 1)
2742 && op2 == TREE_OPERAND (exp, 2))
2745 new = fold (build (code, TREE_TYPE (exp), op0, op1, op2));
2758 /* If this expression is getting a value from a PLACEHOLDER_EXPR
2759 and it is the right field, replace it with R. */
2760 for (inner = TREE_OPERAND (exp, 0);
2761 TREE_CODE_CLASS (TREE_CODE (inner)) == 'r';
2762 inner = TREE_OPERAND (inner, 0))
2764 if (TREE_CODE (inner) == PLACEHOLDER_EXPR
2765 && TREE_OPERAND (exp, 1) == f)
2768 /* If this expression hasn't been completed let, leave it
2770 if (TREE_CODE (inner) == PLACEHOLDER_EXPR
2771 && TREE_TYPE (inner) == 0)
2774 op0 = substitute_in_expr (TREE_OPERAND (exp, 0), f, r);
2775 if (op0 == TREE_OPERAND (exp, 0))
2778 new = fold (build (code, TREE_TYPE (exp), op0,
2779 TREE_OPERAND (exp, 1)));
2783 op0 = substitute_in_expr (TREE_OPERAND (exp, 0), f, r);
2784 op1 = substitute_in_expr (TREE_OPERAND (exp, 1), f, r);
2785 op2 = substitute_in_expr (TREE_OPERAND (exp, 2), f, r);
2786 if (op0 == TREE_OPERAND (exp, 0) && op1 == TREE_OPERAND (exp, 1)
2787 && op2 == TREE_OPERAND (exp, 2))
2790 new = fold (build (code, TREE_TYPE (exp), op0, op1, op2));
2795 op0 = substitute_in_expr (TREE_OPERAND (exp, 0), f, r);
2796 if (op0 == TREE_OPERAND (exp, 0))
2799 new = fold (build1 (code, TREE_TYPE (exp), op0));
2811 TREE_READONLY (new) = TREE_READONLY (exp);
2815 /* Stabilize a reference so that we can use it any number of times
2816 without causing its operands to be evaluated more than once.
2817 Returns the stabilized reference. This works by means of save_expr,
2818 so see the caveats in the comments about save_expr.
2820 Also allows conversion expressions whose operands are references.
2821 Any other kind of expression is returned unchanged. */
2824 stabilize_reference (ref)
2827 register tree result;
2828 register enum tree_code code = TREE_CODE (ref);
2835 /* No action is needed in this case. */
2841 case FIX_TRUNC_EXPR:
2842 case FIX_FLOOR_EXPR:
2843 case FIX_ROUND_EXPR:
2845 result = build_nt (code, stabilize_reference (TREE_OPERAND (ref, 0)));
2849 result = build_nt (INDIRECT_REF,
2850 stabilize_reference_1 (TREE_OPERAND (ref, 0)));
2854 result = build_nt (COMPONENT_REF,
2855 stabilize_reference (TREE_OPERAND (ref, 0)),
2856 TREE_OPERAND (ref, 1));
2860 result = build_nt (BIT_FIELD_REF,
2861 stabilize_reference (TREE_OPERAND (ref, 0)),
2862 stabilize_reference_1 (TREE_OPERAND (ref, 1)),
2863 stabilize_reference_1 (TREE_OPERAND (ref, 2)));
2867 result = build_nt (ARRAY_REF,
2868 stabilize_reference (TREE_OPERAND (ref, 0)),
2869 stabilize_reference_1 (TREE_OPERAND (ref, 1)));
2873 /* We cannot wrap the first expression in a SAVE_EXPR, as then
2874 it wouldn't be ignored. This matters when dealing with
2876 return stabilize_reference_1 (ref);
2879 result = build1 (INDIRECT_REF, TREE_TYPE (ref),
2880 save_expr (build1 (ADDR_EXPR,
2881 build_pointer_type (TREE_TYPE (ref)),
2886 /* If arg isn't a kind of lvalue we recognize, make no change.
2887 Caller should recognize the error for an invalid lvalue. */
2892 return error_mark_node;
2895 TREE_TYPE (result) = TREE_TYPE (ref);
2896 TREE_READONLY (result) = TREE_READONLY (ref);
2897 TREE_SIDE_EFFECTS (result) = TREE_SIDE_EFFECTS (ref);
2898 TREE_THIS_VOLATILE (result) = TREE_THIS_VOLATILE (ref);
2899 TREE_RAISES (result) = TREE_RAISES (ref);
2904 /* Subroutine of stabilize_reference; this is called for subtrees of
2905 references. Any expression with side-effects must be put in a SAVE_EXPR
2906 to ensure that it is only evaluated once.
2908 We don't put SAVE_EXPR nodes around everything, because assigning very
2909 simple expressions to temporaries causes us to miss good opportunities
2910 for optimizations. Among other things, the opportunity to fold in the
2911 addition of a constant into an addressing mode often gets lost, e.g.
2912 "y[i+1] += x;". In general, we take the approach that we should not make
2913 an assignment unless we are forced into it - i.e., that any non-side effect
2914 operator should be allowed, and that cse should take care of coalescing
2915 multiple utterances of the same expression should that prove fruitful. */
2918 stabilize_reference_1 (e)
2921 register tree result;
2922 register enum tree_code code = TREE_CODE (e);
2924 /* We cannot ignore const expressions because it might be a reference
2925 to a const array but whose index contains side-effects. But we can
2926 ignore things that are actual constant or that already have been
2927 handled by this function. */
2929 if (TREE_CONSTANT (e) || code == SAVE_EXPR)
2932 switch (TREE_CODE_CLASS (code))
2942 /* If the expression has side-effects, then encase it in a SAVE_EXPR
2943 so that it will only be evaluated once. */
2944 /* The reference (r) and comparison (<) classes could be handled as
2945 below, but it is generally faster to only evaluate them once. */
2946 if (TREE_SIDE_EFFECTS (e))
2947 return save_expr (e);
2951 /* Constants need no processing. In fact, we should never reach
2956 /* Division is slow and tends to be compiled with jumps,
2957 especially the division by powers of 2 that is often
2958 found inside of an array reference. So do it just once. */
2959 if (code == TRUNC_DIV_EXPR || code == TRUNC_MOD_EXPR
2960 || code == FLOOR_DIV_EXPR || code == FLOOR_MOD_EXPR
2961 || code == CEIL_DIV_EXPR || code == CEIL_MOD_EXPR
2962 || code == ROUND_DIV_EXPR || code == ROUND_MOD_EXPR)
2963 return save_expr (e);
2964 /* Recursively stabilize each operand. */
2965 result = build_nt (code, stabilize_reference_1 (TREE_OPERAND (e, 0)),
2966 stabilize_reference_1 (TREE_OPERAND (e, 1)));
2970 /* Recursively stabilize each operand. */
2971 result = build_nt (code, stabilize_reference_1 (TREE_OPERAND (e, 0)));
2978 TREE_TYPE (result) = TREE_TYPE (e);
2979 TREE_READONLY (result) = TREE_READONLY (e);
2980 TREE_SIDE_EFFECTS (result) = TREE_SIDE_EFFECTS (e);
2981 TREE_THIS_VOLATILE (result) = TREE_THIS_VOLATILE (e);
2982 TREE_RAISES (result) = TREE_RAISES (e);
2987 /* Low-level constructors for expressions. */
2989 /* Build an expression of code CODE, data type TYPE,
2990 and operands as specified by the arguments ARG1 and following arguments.
2991 Expressions and reference nodes can be created this way.
2992 Constants, decls, types and misc nodes cannot be. */
2995 build VPROTO((enum tree_code code, tree tt, ...))
2997 #ifndef ANSI_PROTOTYPES
2998 enum tree_code code;
3003 register int length;
3008 #ifndef ANSI_PROTOTYPES
3009 code = va_arg (p, enum tree_code);
3010 tt = va_arg (p, tree);
3013 t = make_node (code);
3014 length = tree_code_length[(int) code];
3019 /* This is equivalent to the loop below, but faster. */
3020 register tree arg0 = va_arg (p, tree);
3021 register tree arg1 = va_arg (p, tree);
3022 TREE_OPERAND (t, 0) = arg0;
3023 TREE_OPERAND (t, 1) = arg1;
3024 if ((arg0 && TREE_SIDE_EFFECTS (arg0))
3025 || (arg1 && TREE_SIDE_EFFECTS (arg1)))
3026 TREE_SIDE_EFFECTS (t) = 1;
3028 = (arg0 && TREE_RAISES (arg0)) || (arg1 && TREE_RAISES (arg1));
3030 else if (length == 1)
3032 register tree arg0 = va_arg (p, tree);
3034 /* Call build1 for this! */
3035 if (TREE_CODE_CLASS (code) != 's')
3037 TREE_OPERAND (t, 0) = arg0;
3038 if (arg0 && TREE_SIDE_EFFECTS (arg0))
3039 TREE_SIDE_EFFECTS (t) = 1;
3040 TREE_RAISES (t) = (arg0 && TREE_RAISES (arg0));
3044 for (i = 0; i < length; i++)
3046 register tree operand = va_arg (p, tree);
3047 TREE_OPERAND (t, i) = operand;
3050 if (TREE_SIDE_EFFECTS (operand))
3051 TREE_SIDE_EFFECTS (t) = 1;
3052 if (TREE_RAISES (operand))
3053 TREE_RAISES (t) = 1;
3061 /* Same as above, but only builds for unary operators.
3062 Saves lions share of calls to `build'; cuts down use
3063 of varargs, which is expensive for RISC machines. */
3066 build1 (code, type, node)
3067 enum tree_code code;
3071 register struct obstack *obstack = expression_obstack;
3072 register int length;
3073 #ifdef GATHER_STATISTICS
3074 register tree_node_kind kind;
3078 #ifdef GATHER_STATISTICS
3079 if (TREE_CODE_CLASS (code) == 'r')
3085 length = sizeof (struct tree_exp);
3087 t = (tree) obstack_alloc (obstack, length);
3088 bzero ((PTR) t, length);
3090 #ifdef GATHER_STATISTICS
3091 tree_node_counts[(int)kind]++;
3092 tree_node_sizes[(int)kind] += length;
3095 TREE_TYPE (t) = type;
3096 TREE_SET_CODE (t, code);
3098 if (obstack == &permanent_obstack)
3099 TREE_PERMANENT (t) = 1;
3101 TREE_OPERAND (t, 0) = node;
3104 if (TREE_SIDE_EFFECTS (node))
3105 TREE_SIDE_EFFECTS (t) = 1;
3106 if (TREE_RAISES (node))
3107 TREE_RAISES (t) = 1;
3113 /* Similar except don't specify the TREE_TYPE
3114 and leave the TREE_SIDE_EFFECTS as 0.
3115 It is permissible for arguments to be null,
3116 or even garbage if their values do not matter. */
3119 build_nt VPROTO((enum tree_code code, ...))
3121 #ifndef ANSI_PROTOTYPES
3122 enum tree_code code;
3126 register int length;
3131 #ifndef ANSI_PROTOTYPES
3132 code = va_arg (p, enum tree_code);
3135 t = make_node (code);
3136 length = tree_code_length[(int) code];
3138 for (i = 0; i < length; i++)
3139 TREE_OPERAND (t, i) = va_arg (p, tree);
3145 /* Similar to `build_nt', except we build
3146 on the temp_decl_obstack, regardless. */
3149 build_parse_node VPROTO((enum tree_code code, ...))
3151 #ifndef ANSI_PROTOTYPES
3152 enum tree_code code;
3154 register struct obstack *ambient_obstack = expression_obstack;
3157 register int length;
3162 #ifndef ANSI_PROTOTYPES
3163 code = va_arg (p, enum tree_code);
3166 expression_obstack = &temp_decl_obstack;
3168 t = make_node (code);
3169 length = tree_code_length[(int) code];
3171 for (i = 0; i < length; i++)
3172 TREE_OPERAND (t, i) = va_arg (p, tree);
3175 expression_obstack = ambient_obstack;
3180 /* Commented out because this wants to be done very
3181 differently. See cp-lex.c. */
3183 build_op_identifier (op1, op2)
3186 register tree t = make_node (OP_IDENTIFIER);
3187 TREE_PURPOSE (t) = op1;
3188 TREE_VALUE (t) = op2;
3193 /* Create a DECL_... node of code CODE, name NAME and data type TYPE.
3194 We do NOT enter this node in any sort of symbol table.
3196 layout_decl is used to set up the decl's storage layout.
3197 Other slots are initialized to 0 or null pointers. */
3200 build_decl (code, name, type)
3201 enum tree_code code;
3206 t = make_node (code);
3208 /* if (type == error_mark_node)
3209 type = integer_type_node; */
3210 /* That is not done, deliberately, so that having error_mark_node
3211 as the type can suppress useless errors in the use of this variable. */
3213 DECL_NAME (t) = name;
3214 DECL_ASSEMBLER_NAME (t) = name;
3215 TREE_TYPE (t) = type;
3217 if (code == VAR_DECL || code == PARM_DECL || code == RESULT_DECL)
3219 else if (code == FUNCTION_DECL)
3220 DECL_MODE (t) = FUNCTION_MODE;
3225 /* BLOCK nodes are used to represent the structure of binding contours
3226 and declarations, once those contours have been exited and their contents
3227 compiled. This information is used for outputting debugging info. */
3230 build_block (vars, tags, subblocks, supercontext, chain)
3231 tree vars, tags, subblocks, supercontext, chain;
3233 register tree block = make_node (BLOCK);
3234 BLOCK_VARS (block) = vars;
3235 BLOCK_TYPE_TAGS (block) = tags;
3236 BLOCK_SUBBLOCKS (block) = subblocks;
3237 BLOCK_SUPERCONTEXT (block) = supercontext;
3238 BLOCK_CHAIN (block) = chain;
3242 /* EXPR_WITH_FILE_LOCATION are used to keep track of the exact
3243 location where an expression or an identifier were encountered. It
3244 is necessary for languages where the frontend parser will handle
3245 recursively more than one file (Java is one of them). */
3248 build_expr_wfl (node, file, line, col)
3253 static const char *last_file = 0;
3254 static tree last_filenode = NULL_TREE;
3255 register tree wfl = make_node (EXPR_WITH_FILE_LOCATION);
3257 EXPR_WFL_NODE (wfl) = node;
3258 EXPR_WFL_SET_LINECOL (wfl, line, col);
3259 if (file != last_file)
3262 last_filenode = file ? get_identifier (file) : NULL_TREE;
3264 EXPR_WFL_FILENAME_NODE (wfl) = last_filenode;
3267 TREE_SIDE_EFFECTS (wfl) = TREE_SIDE_EFFECTS (node);
3268 TREE_TYPE (wfl) = TREE_TYPE (node);
3273 /* Return a declaration like DDECL except that its DECL_MACHINE_ATTRIBUTE
3277 build_decl_attribute_variant (ddecl, attribute)
3278 tree ddecl, attribute;
3280 DECL_MACHINE_ATTRIBUTES (ddecl) = attribute;
3284 /* Return a type like TTYPE except that its TYPE_ATTRIBUTE
3287 Record such modified types already made so we don't make duplicates. */
3290 build_type_attribute_variant (ttype, attribute)
3291 tree ttype, attribute;
3293 if ( ! attribute_list_equal (TYPE_ATTRIBUTES (ttype), attribute))
3295 register int hashcode;
3296 register struct obstack *ambient_obstack = current_obstack;
3299 if (ambient_obstack != &permanent_obstack)
3300 current_obstack = TYPE_OBSTACK (ttype);
3302 ntype = copy_node (ttype);
3303 current_obstack = ambient_obstack;
3305 TYPE_POINTER_TO (ntype) = 0;
3306 TYPE_REFERENCE_TO (ntype) = 0;
3307 TYPE_ATTRIBUTES (ntype) = attribute;
3309 /* Create a new main variant of TYPE. */
3310 TYPE_MAIN_VARIANT (ntype) = ntype;
3311 TYPE_NEXT_VARIANT (ntype) = 0;
3312 set_type_quals (ntype, TYPE_UNQUALIFIED);
3314 hashcode = TYPE_HASH (TREE_CODE (ntype))
3315 + TYPE_HASH (TREE_TYPE (ntype))
3316 + attribute_hash_list (attribute);
3318 switch (TREE_CODE (ntype))
3321 hashcode += TYPE_HASH (TYPE_ARG_TYPES (ntype));
3324 hashcode += TYPE_HASH (TYPE_DOMAIN (ntype));
3327 hashcode += TYPE_HASH (TYPE_MAX_VALUE (ntype));
3330 hashcode += TYPE_HASH (TYPE_PRECISION (ntype));
3336 ntype = type_hash_canon (hashcode, ntype);
3337 ttype = build_qualified_type (ntype, TYPE_QUALS (ttype));
3343 /* Return a 1 if ATTR_NAME and ATTR_ARGS is valid for either declaration DECL
3344 or type TYPE and 0 otherwise. Validity is determined the configuration
3345 macros VALID_MACHINE_DECL_ATTRIBUTE and VALID_MACHINE_TYPE_ATTRIBUTE. */
3348 valid_machine_attribute (attr_name, attr_args, decl, type)
3350 tree attr_args ATTRIBUTE_UNUSED;
3351 tree decl ATTRIBUTE_UNUSED;
3352 tree type ATTRIBUTE_UNUSED;
3355 #ifdef VALID_MACHINE_DECL_ATTRIBUTE
3356 tree decl_attr_list = decl != 0 ? DECL_MACHINE_ATTRIBUTES (decl) : 0;
3358 #ifdef VALID_MACHINE_TYPE_ATTRIBUTE
3359 tree type_attr_list = TYPE_ATTRIBUTES (type);
3362 if (TREE_CODE (attr_name) != IDENTIFIER_NODE)
3365 #ifdef VALID_MACHINE_DECL_ATTRIBUTE
3367 && VALID_MACHINE_DECL_ATTRIBUTE (decl, decl_attr_list, attr_name, attr_args))
3369 tree attr = lookup_attribute (IDENTIFIER_POINTER (attr_name),
3372 if (attr != NULL_TREE)
3374 /* Override existing arguments. Declarations are unique so we can
3375 modify this in place. */
3376 TREE_VALUE (attr) = attr_args;
3380 decl_attr_list = tree_cons (attr_name, attr_args, decl_attr_list);
3381 decl = build_decl_attribute_variant (decl, decl_attr_list);
3388 #ifdef VALID_MACHINE_TYPE_ATTRIBUTE
3390 /* Don't apply the attribute to both the decl and the type. */;
3391 else if (VALID_MACHINE_TYPE_ATTRIBUTE (type, type_attr_list, attr_name,
3394 tree attr = lookup_attribute (IDENTIFIER_POINTER (attr_name),
3397 if (attr != NULL_TREE)
3399 /* Override existing arguments.
3400 ??? This currently works since attribute arguments are not
3401 included in `attribute_hash_list'. Something more complicated
3402 may be needed in the future. */
3403 TREE_VALUE (attr) = attr_args;
3407 /* If this is part of a declaration, create a type variant,
3408 otherwise, this is part of a type definition, so add it
3409 to the base type. */
3410 type_attr_list = tree_cons (attr_name, attr_args, type_attr_list);
3412 type = build_type_attribute_variant (type, type_attr_list);
3414 TYPE_ATTRIBUTES (type) = type_attr_list;
3417 TREE_TYPE (decl) = type;
3421 /* Handle putting a type attribute on pointer-to-function-type by putting
3422 the attribute on the function type. */
3423 else if (POINTER_TYPE_P (type)
3424 && TREE_CODE (TREE_TYPE (type)) == FUNCTION_TYPE
3425 && VALID_MACHINE_TYPE_ATTRIBUTE (TREE_TYPE (type), type_attr_list,
3426 attr_name, attr_args))
3428 tree inner_type = TREE_TYPE (type);
3429 tree inner_attr_list = TYPE_ATTRIBUTES (inner_type);
3430 tree attr = lookup_attribute (IDENTIFIER_POINTER (attr_name),
3433 if (attr != NULL_TREE)
3434 TREE_VALUE (attr) = attr_args;
3437 inner_attr_list = tree_cons (attr_name, attr_args, inner_attr_list);
3438 inner_type = build_type_attribute_variant (inner_type,
3443 TREE_TYPE (decl) = build_pointer_type (inner_type);
3446 /* Clear TYPE_POINTER_TO for the old inner type, since
3447 `type' won't be pointing to it anymore. */
3448 TYPE_POINTER_TO (TREE_TYPE (type)) = NULL_TREE;
3449 TREE_TYPE (type) = inner_type;
3459 /* Return non-zero if IDENT is a valid name for attribute ATTR,
3462 We try both `text' and `__text__', ATTR may be either one. */
3463 /* ??? It might be a reasonable simplification to require ATTR to be only
3464 `text'. One might then also require attribute lists to be stored in
3465 their canonicalized form. */
3468 is_attribute_p (attr, ident)
3472 int ident_len, attr_len;
3475 if (TREE_CODE (ident) != IDENTIFIER_NODE)
3478 if (strcmp (attr, IDENTIFIER_POINTER (ident)) == 0)
3481 p = IDENTIFIER_POINTER (ident);
3482 ident_len = strlen (p);
3483 attr_len = strlen (attr);
3485 /* If ATTR is `__text__', IDENT must be `text'; and vice versa. */
3489 || attr[attr_len - 2] != '_'
3490 || attr[attr_len - 1] != '_')
3492 if (ident_len == attr_len - 4
3493 && strncmp (attr + 2, p, attr_len - 4) == 0)
3498 if (ident_len == attr_len + 4
3499 && p[0] == '_' && p[1] == '_'
3500 && p[ident_len - 2] == '_' && p[ident_len - 1] == '_'
3501 && strncmp (attr, p + 2, attr_len) == 0)
3508 /* Given an attribute name and a list of attributes, return a pointer to the
3509 attribute's list element if the attribute is part of the list, or NULL_TREE
3513 lookup_attribute (attr_name, list)
3514 const char *attr_name;
3519 for (l = list; l; l = TREE_CHAIN (l))
3521 if (TREE_CODE (TREE_PURPOSE (l)) != IDENTIFIER_NODE)
3523 if (is_attribute_p (attr_name, TREE_PURPOSE (l)))
3530 /* Return an attribute list that is the union of a1 and a2. */
3533 merge_attributes (a1, a2)
3534 register tree a1, a2;
3538 /* Either one unset? Take the set one. */
3540 if (! (attributes = a1))
3543 /* One that completely contains the other? Take it. */
3545 else if (a2 && ! attribute_list_contained (a1, a2))
3547 if (attribute_list_contained (a2, a1))
3551 /* Pick the longest list, and hang on the other list. */
3552 /* ??? For the moment we punt on the issue of attrs with args. */
3554 if (list_length (a1) < list_length (a2))
3555 attributes = a2, a2 = a1;
3557 for (; a2; a2 = TREE_CHAIN (a2))
3558 if (lookup_attribute (IDENTIFIER_POINTER (TREE_PURPOSE (a2)),
3559 attributes) == NULL_TREE)
3561 a1 = copy_node (a2);
3562 TREE_CHAIN (a1) = attributes;
3570 /* Given types T1 and T2, merge their attributes and return
3574 merge_machine_type_attributes (t1, t2)
3577 #ifdef MERGE_MACHINE_TYPE_ATTRIBUTES
3578 return MERGE_MACHINE_TYPE_ATTRIBUTES (t1, t2);
3580 return merge_attributes (TYPE_ATTRIBUTES (t1),
3581 TYPE_ATTRIBUTES (t2));
3585 /* Given decls OLDDECL and NEWDECL, merge their attributes and return
3589 merge_machine_decl_attributes (olddecl, newdecl)
3590 tree olddecl, newdecl;
3592 #ifdef MERGE_MACHINE_DECL_ATTRIBUTES
3593 return MERGE_MACHINE_DECL_ATTRIBUTES (olddecl, newdecl);
3595 return merge_attributes (DECL_MACHINE_ATTRIBUTES (olddecl),
3596 DECL_MACHINE_ATTRIBUTES (newdecl));
3600 /* Set the type qualifiers for TYPE to TYPE_QUALS, which is a bitmask
3601 of the various TYPE_QUAL values. */
3604 set_type_quals (type, type_quals)
3608 TYPE_READONLY (type) = (type_quals & TYPE_QUAL_CONST) != 0;
3609 TYPE_VOLATILE (type) = (type_quals & TYPE_QUAL_VOLATILE) != 0;
3610 TYPE_RESTRICT (type) = (type_quals & TYPE_QUAL_RESTRICT) != 0;
3613 /* Given a type node TYPE and a TYPE_QUALIFIER_SET, return a type for
3614 the same kind of data as TYPE describes. Variants point to the
3615 "main variant" (which has no qualifiers set) via TYPE_MAIN_VARIANT,
3616 and it points to a chain of other variants so that duplicate
3617 variants are never made. Only main variants should ever appear as
3618 types of expressions. */
3621 build_qualified_type (type, type_quals)
3627 /* Search the chain of variants to see if there is already one there just
3628 like the one we need to have. If so, use that existing one. We must
3629 preserve the TYPE_NAME, since there is code that depends on this. */
3631 for (t = TYPE_MAIN_VARIANT (type); t; t = TYPE_NEXT_VARIANT (t))
3632 if (TYPE_QUALS (t) == type_quals && TYPE_NAME (t) == TYPE_NAME (type))
3635 /* We need a new one. */
3636 t = build_type_copy (type);
3637 set_type_quals (t, type_quals);
3641 /* Create a new variant of TYPE, equivalent but distinct.
3642 This is so the caller can modify it. */
3645 build_type_copy (type)
3648 register tree t, m = TYPE_MAIN_VARIANT (type);
3649 register struct obstack *ambient_obstack = current_obstack;
3651 current_obstack = TYPE_OBSTACK (type);
3652 t = copy_node (type);
3653 current_obstack = ambient_obstack;
3655 TYPE_POINTER_TO (t) = 0;
3656 TYPE_REFERENCE_TO (t) = 0;
3658 /* Add this type to the chain of variants of TYPE. */
3659 TYPE_NEXT_VARIANT (t) = TYPE_NEXT_VARIANT (m);
3660 TYPE_NEXT_VARIANT (m) = t;
3665 /* Hashing of types so that we don't make duplicates.
3666 The entry point is `type_hash_canon'. */
3668 /* Each hash table slot is a bucket containing a chain
3669 of these structures. */
3673 struct type_hash *next; /* Next structure in the bucket. */
3674 int hashcode; /* Hash code of this type. */
3675 tree type; /* The type recorded here. */
3678 /* Now here is the hash table. When recording a type, it is added
3679 to the slot whose index is the hash code mod the table size.
3680 Note that the hash table is used for several kinds of types
3681 (function types, array types and array index range types, for now).
3682 While all these live in the same table, they are completely independent,
3683 and the hash code is computed differently for each of these. */
3685 #define TYPE_HASH_SIZE 59
3686 struct type_hash *type_hash_table[TYPE_HASH_SIZE];
3688 /* Compute a hash code for a list of types (chain of TREE_LIST nodes
3689 with types in the TREE_VALUE slots), by adding the hash codes
3690 of the individual types. */
3693 type_hash_list (list)
3696 register int hashcode;
3698 for (hashcode = 0, tail = list; tail; tail = TREE_CHAIN (tail))
3699 hashcode += TYPE_HASH (TREE_VALUE (tail));
3703 /* Look in the type hash table for a type isomorphic to TYPE.
3704 If one is found, return it. Otherwise return 0. */
3707 type_hash_lookup (hashcode, type)
3711 register struct type_hash *h;
3712 for (h = type_hash_table[hashcode % TYPE_HASH_SIZE]; h; h = h->next)
3713 if (h->hashcode == hashcode
3714 && TREE_CODE (h->type) == TREE_CODE (type)
3715 && TREE_TYPE (h->type) == TREE_TYPE (type)
3716 && attribute_list_equal (TYPE_ATTRIBUTES (h->type),
3717 TYPE_ATTRIBUTES (type))
3718 && (TYPE_MAX_VALUE (h->type) == TYPE_MAX_VALUE (type)
3719 || tree_int_cst_equal (TYPE_MAX_VALUE (h->type),
3720 TYPE_MAX_VALUE (type)))
3721 && (TYPE_MIN_VALUE (h->type) == TYPE_MIN_VALUE (type)
3722 || tree_int_cst_equal (TYPE_MIN_VALUE (h->type),
3723 TYPE_MIN_VALUE (type)))
3724 /* Note that TYPE_DOMAIN is TYPE_ARG_TYPES for FUNCTION_TYPE. */
3725 && (TYPE_DOMAIN (h->type) == TYPE_DOMAIN (type)
3726 || (TYPE_DOMAIN (h->type)
3727 && TREE_CODE (TYPE_DOMAIN (h->type)) == TREE_LIST
3728 && TYPE_DOMAIN (type)
3729 && TREE_CODE (TYPE_DOMAIN (type)) == TREE_LIST
3730 && type_list_equal (TYPE_DOMAIN (h->type),
3731 TYPE_DOMAIN (type)))))
3736 /* Add an entry to the type-hash-table
3737 for a type TYPE whose hash code is HASHCODE. */
3740 type_hash_add (hashcode, type)
3744 register struct type_hash *h;
3746 h = (struct type_hash *) oballoc (sizeof (struct type_hash));
3747 h->hashcode = hashcode;
3749 h->next = type_hash_table[hashcode % TYPE_HASH_SIZE];
3750 type_hash_table[hashcode % TYPE_HASH_SIZE] = h;
3753 /* Given TYPE, and HASHCODE its hash code, return the canonical
3754 object for an identical type if one already exists.
3755 Otherwise, return TYPE, and record it as the canonical object
3756 if it is a permanent object.
3758 To use this function, first create a type of the sort you want.
3759 Then compute its hash code from the fields of the type that
3760 make it different from other similar types.
3761 Then call this function and use the value.
3762 This function frees the type you pass in if it is a duplicate. */
3764 /* Set to 1 to debug without canonicalization. Never set by program. */
3765 int debug_no_type_hash = 0;
3768 type_hash_canon (hashcode, type)
3774 if (debug_no_type_hash)
3777 t1 = type_hash_lookup (hashcode, type);
3780 obstack_free (TYPE_OBSTACK (type), type);
3781 #ifdef GATHER_STATISTICS
3782 tree_node_counts[(int)t_kind]--;
3783 tree_node_sizes[(int)t_kind] -= sizeof (struct tree_type);
3788 /* If this is a permanent type, record it for later reuse. */
3789 if (TREE_PERMANENT (type))
3790 type_hash_add (hashcode, type);
3795 /* Compute a hash code for a list of attributes (chain of TREE_LIST nodes
3796 with names in the TREE_PURPOSE slots and args in the TREE_VALUE slots),
3797 by adding the hash codes of the individual attributes. */
3800 attribute_hash_list (list)
3803 register int hashcode;
3805 for (hashcode = 0, tail = list; tail; tail = TREE_CHAIN (tail))
3806 /* ??? Do we want to add in TREE_VALUE too? */
3807 hashcode += TYPE_HASH (TREE_PURPOSE (tail));
3811 /* Given two lists of attributes, return true if list l2 is
3812 equivalent to l1. */
3815 attribute_list_equal (l1, l2)
3818 return attribute_list_contained (l1, l2)
3819 && attribute_list_contained (l2, l1);
3822 /* Given two lists of attributes, return true if list L2 is
3823 completely contained within L1. */
3824 /* ??? This would be faster if attribute names were stored in a canonicalized
3825 form. Otherwise, if L1 uses `foo' and L2 uses `__foo__', the long method
3826 must be used to show these elements are equivalent (which they are). */
3827 /* ??? It's not clear that attributes with arguments will always be handled
3831 attribute_list_contained (l1, l2)
3834 register tree t1, t2;
3836 /* First check the obvious, maybe the lists are identical. */
3840 /* Maybe the lists are similar. */
3841 for (t1 = l1, t2 = l2;
3843 && TREE_PURPOSE (t1) == TREE_PURPOSE (t2)
3844 && TREE_VALUE (t1) == TREE_VALUE (t2);
3845 t1 = TREE_CHAIN (t1), t2 = TREE_CHAIN (t2));
3847 /* Maybe the lists are equal. */
3848 if (t1 == 0 && t2 == 0)
3851 for (; t2; t2 = TREE_CHAIN (t2))
3854 = lookup_attribute (IDENTIFIER_POINTER (TREE_PURPOSE (t2)), l1);
3856 if (attr == NULL_TREE)
3858 if (simple_cst_equal (TREE_VALUE (t2), TREE_VALUE (attr)) != 1)
3865 /* Given two lists of types
3866 (chains of TREE_LIST nodes with types in the TREE_VALUE slots)
3867 return 1 if the lists contain the same types in the same order.
3868 Also, the TREE_PURPOSEs must match. */
3871 type_list_equal (l1, l2)
3874 register tree t1, t2;
3876 for (t1 = l1, t2 = l2; t1 && t2; t1 = TREE_CHAIN (t1), t2 = TREE_CHAIN (t2))
3877 if (TREE_VALUE (t1) != TREE_VALUE (t2)
3878 || (TREE_PURPOSE (t1) != TREE_PURPOSE (t2)
3879 && ! (1 == simple_cst_equal (TREE_PURPOSE (t1), TREE_PURPOSE (t2))
3880 && (TREE_TYPE (TREE_PURPOSE (t1))
3881 == TREE_TYPE (TREE_PURPOSE (t2))))))
3887 /* Nonzero if integer constants T1 and T2
3888 represent the same constant value. */
3891 tree_int_cst_equal (t1, t2)
3896 if (t1 == 0 || t2 == 0)
3898 if (TREE_CODE (t1) == INTEGER_CST
3899 && TREE_CODE (t2) == INTEGER_CST
3900 && TREE_INT_CST_LOW (t1) == TREE_INT_CST_LOW (t2)
3901 && TREE_INT_CST_HIGH (t1) == TREE_INT_CST_HIGH (t2))
3906 /* Nonzero if integer constants T1 and T2 represent values that satisfy <.
3907 The precise way of comparison depends on their data type. */
3910 tree_int_cst_lt (t1, t2)
3916 if (!TREE_UNSIGNED (TREE_TYPE (t1)))
3917 return INT_CST_LT (t1, t2);
3918 return INT_CST_LT_UNSIGNED (t1, t2);
3921 /* Return an indication of the sign of the integer constant T.
3922 The return value is -1 if T < 0, 0 if T == 0, and 1 if T > 0.
3923 Note that -1 will never be returned it T's type is unsigned. */
3926 tree_int_cst_sgn (t)
3929 if (TREE_INT_CST_LOW (t) == 0 && TREE_INT_CST_HIGH (t) == 0)
3931 else if (TREE_UNSIGNED (TREE_TYPE (t)))
3933 else if (TREE_INT_CST_HIGH (t) < 0)
3939 /* Compare two constructor-element-type constants. Return 1 if the lists
3940 are known to be equal; otherwise return 0. */
3943 simple_cst_list_equal (l1, l2)
3946 while (l1 != NULL_TREE && l2 != NULL_TREE)
3948 if (simple_cst_equal (TREE_VALUE (l1), TREE_VALUE (l2)) != 1)
3951 l1 = TREE_CHAIN (l1);
3952 l2 = TREE_CHAIN (l2);
3958 /* Return truthvalue of whether T1 is the same tree structure as T2.
3959 Return 1 if they are the same.
3960 Return 0 if they are understandably different.
3961 Return -1 if either contains tree structure not understood by
3965 simple_cst_equal (t1, t2)
3968 register enum tree_code code1, code2;
3973 if (t1 == 0 || t2 == 0)
3976 code1 = TREE_CODE (t1);
3977 code2 = TREE_CODE (t2);
3979 if (code1 == NOP_EXPR || code1 == CONVERT_EXPR || code1 == NON_LVALUE_EXPR)
3981 if (code2 == NOP_EXPR || code2 == CONVERT_EXPR
3982 || code2 == NON_LVALUE_EXPR)
3983 return simple_cst_equal (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0));
3985 return simple_cst_equal (TREE_OPERAND (t1, 0), t2);
3987 else if (code2 == NOP_EXPR || code2 == CONVERT_EXPR
3988 || code2 == NON_LVALUE_EXPR)
3989 return simple_cst_equal (t1, TREE_OPERAND (t2, 0));
3997 return TREE_INT_CST_LOW (t1) == TREE_INT_CST_LOW (t2)
3998 && TREE_INT_CST_HIGH (t1) == TREE_INT_CST_HIGH (t2);
4001 return REAL_VALUES_IDENTICAL (TREE_REAL_CST (t1), TREE_REAL_CST (t2));
4004 return TREE_STRING_LENGTH (t1) == TREE_STRING_LENGTH (t2)
4005 && !bcmp (TREE_STRING_POINTER (t1), TREE_STRING_POINTER (t2),
4006 TREE_STRING_LENGTH (t1));
4009 if (CONSTRUCTOR_ELTS (t1) == CONSTRUCTOR_ELTS (t2))
4015 return simple_cst_equal (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0));
4018 cmp = simple_cst_equal (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0));
4021 return simple_cst_list_equal (TREE_OPERAND (t1, 1), TREE_OPERAND (t2, 1));
4024 /* Special case: if either target is an unallocated VAR_DECL,
4025 it means that it's going to be unified with whatever the
4026 TARGET_EXPR is really supposed to initialize, so treat it
4027 as being equivalent to anything. */
4028 if ((TREE_CODE (TREE_OPERAND (t1, 0)) == VAR_DECL
4029 && DECL_NAME (TREE_OPERAND (t1, 0)) == NULL_TREE
4030 && DECL_RTL (TREE_OPERAND (t1, 0)) == 0)
4031 || (TREE_CODE (TREE_OPERAND (t2, 0)) == VAR_DECL
4032 && DECL_NAME (TREE_OPERAND (t2, 0)) == NULL_TREE
4033 && DECL_RTL (TREE_OPERAND (t2, 0)) == 0))
4036 cmp = simple_cst_equal (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0));
4039 return simple_cst_equal (TREE_OPERAND (t1, 1), TREE_OPERAND (t2, 1));
4041 case WITH_CLEANUP_EXPR:
4042 cmp = simple_cst_equal (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0));
4045 return simple_cst_equal (TREE_OPERAND (t1, 2), TREE_OPERAND (t1, 2));
4048 if (TREE_OPERAND (t1, 1) == TREE_OPERAND (t2, 1))
4049 return simple_cst_equal (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0));
4062 /* This general rule works for most tree codes. All exceptions should be
4063 handled above. If this is a language-specific tree code, we can't
4064 trust what might be in the operand, so say we don't know
4066 if ((int) code1 >= (int) LAST_AND_UNUSED_TREE_CODE)
4069 switch (TREE_CODE_CLASS (code1))
4079 for (i=0; i<tree_code_length[(int) code1]; ++i)
4081 cmp = simple_cst_equal (TREE_OPERAND (t1, i), TREE_OPERAND (t2, i));
4092 /* Constructors for pointer, array and function types.
4093 (RECORD_TYPE, UNION_TYPE and ENUMERAL_TYPE nodes are
4094 constructed by language-dependent code, not here.) */
4096 /* Construct, lay out and return the type of pointers to TO_TYPE.
4097 If such a type has already been constructed, reuse it. */
4100 build_pointer_type (to_type)
4103 register tree t = TYPE_POINTER_TO (to_type);
4105 /* First, if we already have a type for pointers to TO_TYPE, use it. */
4110 /* We need a new one. Put this in the same obstack as TO_TYPE. */
4111 push_obstacks (TYPE_OBSTACK (to_type), TYPE_OBSTACK (to_type));
4112 t = make_node (POINTER_TYPE);
4115 TREE_TYPE (t) = to_type;
4117 /* Record this type as the pointer to TO_TYPE. */
4118 TYPE_POINTER_TO (to_type) = t;
4120 /* Lay out the type. This function has many callers that are concerned
4121 with expression-construction, and this simplifies them all.
4122 Also, it guarantees the TYPE_SIZE is in the same obstack as the type. */
4128 /* Create a type of integers to be the TYPE_DOMAIN of an ARRAY_TYPE.
4129 MAXVAL should be the maximum value in the domain
4130 (one less than the length of the array).
4132 The maximum value that MAXVAL can have is INT_MAX for a HOST_WIDE_INT.
4133 We don't enforce this limit, that is up to caller (e.g. language front end).
4134 The limit exists because the result is a signed type and we don't handle
4135 sizes that use more than one HOST_WIDE_INT. */
4138 build_index_type (maxval)
4141 register tree itype = make_node (INTEGER_TYPE);
4143 TYPE_PRECISION (itype) = TYPE_PRECISION (sizetype);
4144 TYPE_MIN_VALUE (itype) = size_zero_node;
4146 push_obstacks (TYPE_OBSTACK (itype), TYPE_OBSTACK (itype));
4147 TYPE_MAX_VALUE (itype) = convert (sizetype, maxval);
4150 TYPE_MODE (itype) = TYPE_MODE (sizetype);
4151 TYPE_SIZE (itype) = TYPE_SIZE (sizetype);
4152 TYPE_SIZE_UNIT (itype) = TYPE_SIZE_UNIT (sizetype);
4153 TYPE_ALIGN (itype) = TYPE_ALIGN (sizetype);
4154 if (TREE_CODE (maxval) == INTEGER_CST)
4156 int maxint = (int) TREE_INT_CST_LOW (maxval);
4157 /* If the domain should be empty, make sure the maxval
4158 remains -1 and is not spoiled by truncation. */
4159 if (INT_CST_LT (maxval, integer_zero_node))
4161 TYPE_MAX_VALUE (itype) = build_int_2 (-1, -1);
4162 TREE_TYPE (TYPE_MAX_VALUE (itype)) = sizetype;
4164 return type_hash_canon (maxint < 0 ? ~maxint : maxint, itype);
4170 /* Create a range of some discrete type TYPE (an INTEGER_TYPE,
4171 ENUMERAL_TYPE, BOOLEAN_TYPE, or CHAR_TYPE), with
4172 low bound LOWVAL and high bound HIGHVAL.
4173 if TYPE==NULL_TREE, sizetype is used. */
4176 build_range_type (type, lowval, highval)
4177 tree type, lowval, highval;
4179 register tree itype = make_node (INTEGER_TYPE);
4181 TREE_TYPE (itype) = type;
4182 if (type == NULL_TREE)
4185 push_obstacks (TYPE_OBSTACK (itype), TYPE_OBSTACK (itype));
4186 TYPE_MIN_VALUE (itype) = convert (type, lowval);
4187 TYPE_MAX_VALUE (itype) = highval ? convert (type, highval) : NULL;
4190 TYPE_PRECISION (itype) = TYPE_PRECISION (type);
4191 TYPE_MODE (itype) = TYPE_MODE (type);
4192 TYPE_SIZE (itype) = TYPE_SIZE (type);
4193 TYPE_SIZE_UNIT (itype) = TYPE_SIZE_UNIT (type);
4194 TYPE_ALIGN (itype) = TYPE_ALIGN (type);
4195 if (TREE_CODE (lowval) == INTEGER_CST)
4197 HOST_WIDE_INT lowint, highint;
4200 lowint = TREE_INT_CST_LOW (lowval);
4201 if (highval && TREE_CODE (highval) == INTEGER_CST)
4202 highint = TREE_INT_CST_LOW (highval);
4204 highint = (~(unsigned HOST_WIDE_INT)0) >> 1;
4206 maxint = (int) (highint - lowint);
4207 return type_hash_canon (maxint < 0 ? ~maxint : maxint, itype);
4213 /* Just like build_index_type, but takes lowval and highval instead
4214 of just highval (maxval). */
4217 build_index_2_type (lowval,highval)
4218 tree lowval, highval;
4220 return build_range_type (NULL_TREE, lowval, highval);
4223 /* Return nonzero iff ITYPE1 and ITYPE2 are equal (in the LISP sense).
4224 Needed because when index types are not hashed, equal index types
4225 built at different times appear distinct, even though structurally,
4229 index_type_equal (itype1, itype2)
4230 tree itype1, itype2;
4232 if (TREE_CODE (itype1) != TREE_CODE (itype2))
4234 if (TREE_CODE (itype1) == INTEGER_TYPE)
4236 if (TYPE_PRECISION (itype1) != TYPE_PRECISION (itype2)
4237 || TYPE_MODE (itype1) != TYPE_MODE (itype2)
4238 || simple_cst_equal (TYPE_SIZE (itype1), TYPE_SIZE (itype2)) != 1
4239 || TYPE_ALIGN (itype1) != TYPE_ALIGN (itype2))
4241 if (1 == simple_cst_equal (TYPE_MIN_VALUE (itype1),
4242 TYPE_MIN_VALUE (itype2))
4243 && 1 == simple_cst_equal (TYPE_MAX_VALUE (itype1),
4244 TYPE_MAX_VALUE (itype2)))
4251 /* Construct, lay out and return the type of arrays of elements with ELT_TYPE
4252 and number of elements specified by the range of values of INDEX_TYPE.
4253 If such a type has already been constructed, reuse it. */
4256 build_array_type (elt_type, index_type)
4257 tree elt_type, index_type;
4262 if (TREE_CODE (elt_type) == FUNCTION_TYPE)
4264 error ("arrays of functions are not meaningful");
4265 elt_type = integer_type_node;
4268 /* Make sure TYPE_POINTER_TO (elt_type) is filled in. */
4269 build_pointer_type (elt_type);
4271 /* Allocate the array after the pointer type,
4272 in case we free it in type_hash_canon. */
4273 t = make_node (ARRAY_TYPE);
4274 TREE_TYPE (t) = elt_type;
4275 TYPE_DOMAIN (t) = index_type;
4277 if (index_type == 0)
4282 hashcode = TYPE_HASH (elt_type) + TYPE_HASH (index_type);
4283 t = type_hash_canon (hashcode, t);
4285 if (TYPE_SIZE (t) == 0)
4290 /* Return the TYPE of the elements comprising
4291 the innermost dimension of ARRAY. */
4294 get_inner_array_type (array)
4297 tree type = TREE_TYPE (array);
4299 while (TREE_CODE (type) == ARRAY_TYPE)
4300 type = TREE_TYPE (type);
4305 /* Construct, lay out and return
4306 the type of functions returning type VALUE_TYPE
4307 given arguments of types ARG_TYPES.
4308 ARG_TYPES is a chain of TREE_LIST nodes whose TREE_VALUEs
4309 are data type nodes for the arguments of the function.
4310 If such a type has already been constructed, reuse it. */
4313 build_function_type (value_type, arg_types)
4314 tree value_type, arg_types;
4319 if (TREE_CODE (value_type) == FUNCTION_TYPE)
4321 error ("function return type cannot be function");
4322 value_type = integer_type_node;
4325 /* Make a node of the sort we want. */
4326 t = make_node (FUNCTION_TYPE);
4327 TREE_TYPE (t) = value_type;
4328 TYPE_ARG_TYPES (t) = arg_types;
4330 /* If we already have such a type, use the old one and free this one. */
4331 hashcode = TYPE_HASH (value_type) + type_hash_list (arg_types);
4332 t = type_hash_canon (hashcode, t);
4334 if (TYPE_SIZE (t) == 0)
4339 /* Build the node for the type of references-to-TO_TYPE. */
4342 build_reference_type (to_type)
4345 register tree t = TYPE_REFERENCE_TO (to_type);
4347 /* First, if we already have a type for pointers to TO_TYPE, use it. */
4352 /* We need a new one. Put this in the same obstack as TO_TYPE. */
4353 push_obstacks (TYPE_OBSTACK (to_type), TYPE_OBSTACK (to_type));
4354 t = make_node (REFERENCE_TYPE);
4357 TREE_TYPE (t) = to_type;
4359 /* Record this type as the pointer to TO_TYPE. */
4360 TYPE_REFERENCE_TO (to_type) = t;
4367 /* Construct, lay out and return the type of methods belonging to class
4368 BASETYPE and whose arguments and values are described by TYPE.
4369 If that type exists already, reuse it.
4370 TYPE must be a FUNCTION_TYPE node. */
4373 build_method_type (basetype, type)
4374 tree basetype, type;
4379 /* Make a node of the sort we want. */
4380 t = make_node (METHOD_TYPE);
4382 if (TREE_CODE (type) != FUNCTION_TYPE)
4385 TYPE_METHOD_BASETYPE (t) = TYPE_MAIN_VARIANT (basetype);
4386 TREE_TYPE (t) = TREE_TYPE (type);
4388 /* The actual arglist for this function includes a "hidden" argument
4389 which is "this". Put it into the list of argument types. */
4392 = tree_cons (NULL_TREE,
4393 build_pointer_type (basetype), TYPE_ARG_TYPES (type));
4395 /* If we already have such a type, use the old one and free this one. */
4396 hashcode = TYPE_HASH (basetype) + TYPE_HASH (type);
4397 t = type_hash_canon (hashcode, t);
4399 if (TYPE_SIZE (t) == 0)
4405 /* Construct, lay out and return the type of offsets to a value
4406 of type TYPE, within an object of type BASETYPE.
4407 If a suitable offset type exists already, reuse it. */
4410 build_offset_type (basetype, type)
4411 tree basetype, type;
4416 /* Make a node of the sort we want. */
4417 t = make_node (OFFSET_TYPE);
4419 TYPE_OFFSET_BASETYPE (t) = TYPE_MAIN_VARIANT (basetype);
4420 TREE_TYPE (t) = type;
4422 /* If we already have such a type, use the old one and free this one. */
4423 hashcode = TYPE_HASH (basetype) + TYPE_HASH (type);
4424 t = type_hash_canon (hashcode, t);
4426 if (TYPE_SIZE (t) == 0)
4432 /* Create a complex type whose components are COMPONENT_TYPE. */
4435 build_complex_type (component_type)
4436 tree component_type;
4441 /* Make a node of the sort we want. */
4442 t = make_node (COMPLEX_TYPE);
4444 TREE_TYPE (t) = TYPE_MAIN_VARIANT (component_type);
4445 set_type_quals (t, TYPE_QUALS (component_type));
4447 /* If we already have such a type, use the old one and free this one. */
4448 hashcode = TYPE_HASH (component_type);
4449 t = type_hash_canon (hashcode, t);
4451 if (TYPE_SIZE (t) == 0)
4457 /* Return OP, stripped of any conversions to wider types as much as is safe.
4458 Converting the value back to OP's type makes a value equivalent to OP.
4460 If FOR_TYPE is nonzero, we return a value which, if converted to
4461 type FOR_TYPE, would be equivalent to converting OP to type FOR_TYPE.
4463 If FOR_TYPE is nonzero, unaligned bit-field references may be changed to the
4464 narrowest type that can hold the value, even if they don't exactly fit.
4465 Otherwise, bit-field references are changed to a narrower type
4466 only if they can be fetched directly from memory in that type.
4468 OP must have integer, real or enumeral type. Pointers are not allowed!
4470 There are some cases where the obvious value we could return
4471 would regenerate to OP if converted to OP's type,
4472 but would not extend like OP to wider types.
4473 If FOR_TYPE indicates such extension is contemplated, we eschew such values.
4474 For example, if OP is (unsigned short)(signed char)-1,
4475 we avoid returning (signed char)-1 if FOR_TYPE is int,
4476 even though extending that to an unsigned short would regenerate OP,
4477 since the result of extending (signed char)-1 to (int)
4478 is different from (int) OP. */
4481 get_unwidened (op, for_type)
4485 /* Set UNS initially if converting OP to FOR_TYPE is a zero-extension. */
4486 register tree type = TREE_TYPE (op);
4487 register unsigned final_prec
4488 = TYPE_PRECISION (for_type != 0 ? for_type : type);
4490 = (for_type != 0 && for_type != type
4491 && final_prec > TYPE_PRECISION (type)
4492 && TREE_UNSIGNED (type));
4493 register tree win = op;
4495 while (TREE_CODE (op) == NOP_EXPR)
4497 register int bitschange
4498 = TYPE_PRECISION (TREE_TYPE (op))
4499 - TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (op, 0)));
4501 /* Truncations are many-one so cannot be removed.
4502 Unless we are later going to truncate down even farther. */
4504 && final_prec > TYPE_PRECISION (TREE_TYPE (op)))
4507 /* See what's inside this conversion. If we decide to strip it,
4509 op = TREE_OPERAND (op, 0);
4511 /* If we have not stripped any zero-extensions (uns is 0),
4512 we can strip any kind of extension.
4513 If we have previously stripped a zero-extension,
4514 only zero-extensions can safely be stripped.
4515 Any extension can be stripped if the bits it would produce
4516 are all going to be discarded later by truncating to FOR_TYPE. */
4520 if (! uns || final_prec <= TYPE_PRECISION (TREE_TYPE (op)))
4522 /* TREE_UNSIGNED says whether this is a zero-extension.
4523 Let's avoid computing it if it does not affect WIN
4524 and if UNS will not be needed again. */
4525 if ((uns || TREE_CODE (op) == NOP_EXPR)
4526 && TREE_UNSIGNED (TREE_TYPE (op)))
4534 if (TREE_CODE (op) == COMPONENT_REF
4535 /* Since type_for_size always gives an integer type. */
4536 && TREE_CODE (type) != REAL_TYPE
4537 /* Don't crash if field not laid out yet. */
4538 && DECL_SIZE (TREE_OPERAND (op, 1)) != 0)
4540 unsigned innerprec = TREE_INT_CST_LOW (DECL_SIZE (TREE_OPERAND (op, 1)));
4541 type = type_for_size (innerprec, TREE_UNSIGNED (TREE_OPERAND (op, 1)));
4543 /* We can get this structure field in the narrowest type it fits in.
4544 If FOR_TYPE is 0, do this only for a field that matches the
4545 narrower type exactly and is aligned for it
4546 The resulting extension to its nominal type (a fullword type)
4547 must fit the same conditions as for other extensions. */
4549 if (innerprec < TYPE_PRECISION (TREE_TYPE (op))
4550 && (for_type || ! DECL_BIT_FIELD (TREE_OPERAND (op, 1)))
4551 && (! uns || final_prec <= innerprec
4552 || TREE_UNSIGNED (TREE_OPERAND (op, 1)))
4555 win = build (COMPONENT_REF, type, TREE_OPERAND (op, 0),
4556 TREE_OPERAND (op, 1));
4557 TREE_SIDE_EFFECTS (win) = TREE_SIDE_EFFECTS (op);
4558 TREE_THIS_VOLATILE (win) = TREE_THIS_VOLATILE (op);
4559 TREE_RAISES (win) = TREE_RAISES (op);
4565 /* Return OP or a simpler expression for a narrower value
4566 which can be sign-extended or zero-extended to give back OP.
4567 Store in *UNSIGNEDP_PTR either 1 if the value should be zero-extended
4568 or 0 if the value should be sign-extended. */
4571 get_narrower (op, unsignedp_ptr)
4575 register int uns = 0;
4577 register tree win = op;
4579 while (TREE_CODE (op) == NOP_EXPR)
4581 register int bitschange
4582 = TYPE_PRECISION (TREE_TYPE (op))
4583 - TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (op, 0)));
4585 /* Truncations are many-one so cannot be removed. */
4589 /* See what's inside this conversion. If we decide to strip it,
4591 op = TREE_OPERAND (op, 0);
4595 /* An extension: the outermost one can be stripped,
4596 but remember whether it is zero or sign extension. */
4598 uns = TREE_UNSIGNED (TREE_TYPE (op));
4599 /* Otherwise, if a sign extension has been stripped,
4600 only sign extensions can now be stripped;
4601 if a zero extension has been stripped, only zero-extensions. */
4602 else if (uns != TREE_UNSIGNED (TREE_TYPE (op)))
4606 else /* bitschange == 0 */
4608 /* A change in nominal type can always be stripped, but we must
4609 preserve the unsignedness. */
4611 uns = TREE_UNSIGNED (TREE_TYPE (op));
4618 if (TREE_CODE (op) == COMPONENT_REF
4619 /* Since type_for_size always gives an integer type. */
4620 && TREE_CODE (TREE_TYPE (op)) != REAL_TYPE)
4622 unsigned innerprec = TREE_INT_CST_LOW (DECL_SIZE (TREE_OPERAND (op, 1)));
4623 tree type = type_for_size (innerprec, TREE_UNSIGNED (op));
4625 /* We can get this structure field in a narrower type that fits it,
4626 but the resulting extension to its nominal type (a fullword type)
4627 must satisfy the same conditions as for other extensions.
4629 Do this only for fields that are aligned (not bit-fields),
4630 because when bit-field insns will be used there is no
4631 advantage in doing this. */
4633 if (innerprec < TYPE_PRECISION (TREE_TYPE (op))
4634 && ! DECL_BIT_FIELD (TREE_OPERAND (op, 1))
4635 && (first || uns == TREE_UNSIGNED (TREE_OPERAND (op, 1)))
4639 uns = TREE_UNSIGNED (TREE_OPERAND (op, 1));
4640 win = build (COMPONENT_REF, type, TREE_OPERAND (op, 0),
4641 TREE_OPERAND (op, 1));
4642 TREE_SIDE_EFFECTS (win) = TREE_SIDE_EFFECTS (op);
4643 TREE_THIS_VOLATILE (win) = TREE_THIS_VOLATILE (op);
4644 TREE_RAISES (win) = TREE_RAISES (op);
4647 *unsignedp_ptr = uns;
4651 /* Nonzero if integer constant C has a value that is permissible
4652 for type TYPE (an INTEGER_TYPE). */
4655 int_fits_type_p (c, type)
4658 if (TREE_UNSIGNED (type))
4659 return (! (TREE_CODE (TYPE_MAX_VALUE (type)) == INTEGER_CST
4660 && INT_CST_LT_UNSIGNED (TYPE_MAX_VALUE (type), c))
4661 && ! (TREE_CODE (TYPE_MIN_VALUE (type)) == INTEGER_CST
4662 && INT_CST_LT_UNSIGNED (c, TYPE_MIN_VALUE (type)))
4663 /* Negative ints never fit unsigned types. */
4664 && ! (TREE_INT_CST_HIGH (c) < 0
4665 && ! TREE_UNSIGNED (TREE_TYPE (c))));
4667 return (! (TREE_CODE (TYPE_MAX_VALUE (type)) == INTEGER_CST
4668 && INT_CST_LT (TYPE_MAX_VALUE (type), c))
4669 && ! (TREE_CODE (TYPE_MIN_VALUE (type)) == INTEGER_CST
4670 && INT_CST_LT (c, TYPE_MIN_VALUE (type)))
4671 /* Unsigned ints with top bit set never fit signed types. */
4672 && ! (TREE_INT_CST_HIGH (c) < 0
4673 && TREE_UNSIGNED (TREE_TYPE (c))));
4676 /* Return the innermost context enclosing DECL that is
4677 a FUNCTION_DECL, or zero if none. */
4680 decl_function_context (decl)
4685 if (TREE_CODE (decl) == ERROR_MARK)
4688 if (TREE_CODE (decl) == SAVE_EXPR)
4689 context = SAVE_EXPR_CONTEXT (decl);
4691 context = DECL_CONTEXT (decl);
4693 while (context && TREE_CODE (context) != FUNCTION_DECL)
4695 if (TREE_CODE_CLASS (TREE_CODE (context)) == 't')
4696 context = TYPE_CONTEXT (context);
4697 else if (TREE_CODE_CLASS (TREE_CODE (context)) == 'd')
4698 context = DECL_CONTEXT (context);
4699 else if (TREE_CODE (context) == BLOCK)
4700 context = BLOCK_SUPERCONTEXT (context);
4702 /* Unhandled CONTEXT !? */
4709 /* Return the innermost context enclosing DECL that is
4710 a RECORD_TYPE, UNION_TYPE or QUAL_UNION_TYPE, or zero if none.
4711 TYPE_DECLs and FUNCTION_DECLs are transparent to this function. */
4714 decl_type_context (decl)
4717 tree context = DECL_CONTEXT (decl);
4721 if (TREE_CODE (context) == RECORD_TYPE
4722 || TREE_CODE (context) == UNION_TYPE
4723 || TREE_CODE (context) == QUAL_UNION_TYPE)
4725 if (TREE_CODE (context) == TYPE_DECL
4726 || TREE_CODE (context) == FUNCTION_DECL)
4727 context = DECL_CONTEXT (context);
4728 else if (TREE_CODE (context) == BLOCK)
4729 context = BLOCK_SUPERCONTEXT (context);
4731 /* Unhandled CONTEXT!? */
4737 /* Print debugging information about the size of the
4738 toplev_inline_obstacks. */
4741 print_inline_obstack_statistics ()
4743 struct simple_obstack_stack *current = toplev_inline_obstacks;
4748 for (; current; current = current->next, ++n_obstacks)
4750 struct obstack *o = current->obstack;
4751 struct _obstack_chunk *chunk = o->chunk;
4753 n_alloc += o->next_free - chunk->contents;
4754 chunk = chunk->prev;
4756 for (; chunk; chunk = chunk->prev, ++n_chunks)
4757 n_alloc += chunk->limit - &chunk->contents[0];
4759 fprintf (stderr, "inline obstacks: %d obstacks, %d bytes, %d chunks\n",
4760 n_obstacks, n_alloc, n_chunks);
4763 /* Print debugging information about the obstack O, named STR. */
4766 print_obstack_statistics (str, o)
4770 struct _obstack_chunk *chunk = o->chunk;
4774 n_alloc += o->next_free - chunk->contents;
4775 chunk = chunk->prev;
4779 n_alloc += chunk->limit - &chunk->contents[0];
4780 chunk = chunk->prev;
4782 fprintf (stderr, "obstack %s: %u bytes, %d chunks\n",
4783 str, n_alloc, n_chunks);
4786 /* Print debugging information about tree nodes generated during the compile,
4787 and any language-specific information. */
4790 dump_tree_statistics ()
4792 #ifdef GATHER_STATISTICS
4794 int total_nodes, total_bytes;
4797 fprintf (stderr, "\n??? tree nodes created\n\n");
4798 #ifdef GATHER_STATISTICS
4799 fprintf (stderr, "Kind Nodes Bytes\n");
4800 fprintf (stderr, "-------------------------------------\n");
4801 total_nodes = total_bytes = 0;
4802 for (i = 0; i < (int) all_kinds; i++)
4804 fprintf (stderr, "%-20s %6d %9d\n", tree_node_kind_names[i],
4805 tree_node_counts[i], tree_node_sizes[i]);
4806 total_nodes += tree_node_counts[i];
4807 total_bytes += tree_node_sizes[i];
4809 fprintf (stderr, "%-20s %9d\n", "identifier names", id_string_size);
4810 fprintf (stderr, "-------------------------------------\n");
4811 fprintf (stderr, "%-20s %6d %9d\n", "Total", total_nodes, total_bytes);
4812 fprintf (stderr, "-------------------------------------\n");
4814 fprintf (stderr, "(No per-node statistics)\n");
4816 print_obstack_statistics ("permanent_obstack", &permanent_obstack);
4817 print_obstack_statistics ("maybepermanent_obstack", &maybepermanent_obstack);
4818 print_obstack_statistics ("temporary_obstack", &temporary_obstack);
4819 print_obstack_statistics ("momentary_obstack", &momentary_obstack);
4820 print_obstack_statistics ("temp_decl_obstack", &temp_decl_obstack);
4821 print_inline_obstack_statistics ();
4822 print_lang_statistics ();
4825 #define FILE_FUNCTION_PREFIX_LEN 9
4827 #ifndef NO_DOLLAR_IN_LABEL
4828 #define FILE_FUNCTION_FORMAT "_GLOBAL_$%s$%s"
4829 #else /* NO_DOLLAR_IN_LABEL */
4830 #ifndef NO_DOT_IN_LABEL
4831 #define FILE_FUNCTION_FORMAT "_GLOBAL_.%s.%s"
4832 #else /* NO_DOT_IN_LABEL */
4833 #define FILE_FUNCTION_FORMAT "_GLOBAL__%s_%s"
4834 #endif /* NO_DOT_IN_LABEL */
4835 #endif /* NO_DOLLAR_IN_LABEL */
4837 extern char * first_global_object_name;
4838 extern char * weak_global_object_name;
4840 /* Appends 6 random characters to TEMPLATE to (hopefully) avoid name
4841 clashes in cases where we can't reliably choose a unique name.
4843 Derived from mkstemp.c in libiberty. */
4846 append_random_chars (template)
4849 static const char letters[]
4850 = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789";
4851 static unsigned HOST_WIDE_INT value;
4852 unsigned HOST_WIDE_INT v;
4854 #ifdef HAVE_GETTIMEOFDAY
4858 template += strlen (template);
4860 #ifdef HAVE_GETTIMEOFDAY
4861 /* Get some more or less random data. */
4862 gettimeofday (&tv, NULL);
4863 value += ((unsigned HOST_WIDE_INT) tv.tv_usec << 16) ^ tv.tv_sec ^ getpid ();
4870 /* Fill in the random bits. */
4871 template[0] = letters[v % 62];
4873 template[1] = letters[v % 62];
4875 template[2] = letters[v % 62];
4877 template[3] = letters[v % 62];
4879 template[4] = letters[v % 62];
4881 template[5] = letters[v % 62];
4886 /* Generate a name for a function unique to this translation unit.
4887 TYPE is some string to identify the purpose of this function to the
4888 linker or collect2. */
4891 get_file_function_name_long (type)
4897 if (first_global_object_name)
4898 p = first_global_object_name;
4901 /* We don't have anything that we know to be unique to this translation
4902 unit, so use what we do have and throw in some randomness. */
4904 const char *name = weak_global_object_name;
4905 const char *file = main_input_filename;
4910 file = input_filename;
4912 p = (char *) alloca (7 + strlen (name) + strlen (file));
4914 sprintf (p, "%s%s", name, file);
4915 append_random_chars (p);
4918 buf = (char *) alloca (sizeof (FILE_FUNCTION_FORMAT) + strlen (p)
4921 /* Set up the name of the file-level functions we may need. */
4922 /* Use a global object (which is already required to be unique over
4923 the program) rather than the file name (which imposes extra
4924 constraints). -- Raeburn@MIT.EDU, 10 Jan 1990. */
4925 sprintf (buf, FILE_FUNCTION_FORMAT, type, p);
4927 /* Don't need to pull weird characters out of global names. */
4928 if (p != first_global_object_name)
4930 for (p = buf+11; *p; p++)
4931 if (! ((*p >= '0' && *p <= '9')
4932 #if 0 /* we always want labels, which are valid C++ identifiers (+ `$') */
4933 #ifndef ASM_IDENTIFY_GCC /* this is required if `.' is invalid -- k. raeburn */
4937 #ifndef NO_DOLLAR_IN_LABEL /* this for `$'; unlikely, but... -- kr */
4940 #ifndef NO_DOT_IN_LABEL /* this for `.'; unlikely, but... */
4943 || (*p >= 'A' && *p <= 'Z')
4944 || (*p >= 'a' && *p <= 'z')))
4948 return get_identifier (buf);
4951 /* If KIND=='I', return a suitable global initializer (constructor) name.
4952 If KIND=='D', return a suitable global clean-up (destructor) name. */
4955 get_file_function_name (kind)
4962 return get_file_function_name_long (p);
4966 /* Expand (the constant part of) a SET_TYPE CONSTRUCTOR node.
4967 The result is placed in BUFFER (which has length BIT_SIZE),
4968 with one bit in each char ('\000' or '\001').
4970 If the constructor is constant, NULL_TREE is returned.
4971 Otherwise, a TREE_LIST of the non-constant elements is emitted. */
4974 get_set_constructor_bits (init, buffer, bit_size)
4981 HOST_WIDE_INT domain_min
4982 = TREE_INT_CST_LOW (TYPE_MIN_VALUE (TYPE_DOMAIN (TREE_TYPE (init))));
4983 tree non_const_bits = NULL_TREE;
4984 for (i = 0; i < bit_size; i++)
4987 for (vals = TREE_OPERAND (init, 1);
4988 vals != NULL_TREE; vals = TREE_CHAIN (vals))
4990 if (TREE_CODE (TREE_VALUE (vals)) != INTEGER_CST
4991 || (TREE_PURPOSE (vals) != NULL_TREE
4992 && TREE_CODE (TREE_PURPOSE (vals)) != INTEGER_CST))
4994 = tree_cons (TREE_PURPOSE (vals), TREE_VALUE (vals), non_const_bits);
4995 else if (TREE_PURPOSE (vals) != NULL_TREE)
4997 /* Set a range of bits to ones. */
4998 HOST_WIDE_INT lo_index
4999 = TREE_INT_CST_LOW (TREE_PURPOSE (vals)) - domain_min;
5000 HOST_WIDE_INT hi_index
5001 = TREE_INT_CST_LOW (TREE_VALUE (vals)) - domain_min;
5002 if (lo_index < 0 || lo_index >= bit_size
5003 || hi_index < 0 || hi_index >= bit_size)
5005 for ( ; lo_index <= hi_index; lo_index++)
5006 buffer[lo_index] = 1;
5010 /* Set a single bit to one. */
5012 = TREE_INT_CST_LOW (TREE_VALUE (vals)) - domain_min;
5013 if (index < 0 || index >= bit_size)
5015 error ("invalid initializer for bit string");
5021 return non_const_bits;
5024 /* Expand (the constant part of) a SET_TYPE CONSTRUCTOR node.
5025 The result is placed in BUFFER (which is an array of bytes).
5026 If the constructor is constant, NULL_TREE is returned.
5027 Otherwise, a TREE_LIST of the non-constant elements is emitted. */
5030 get_set_constructor_bytes (init, buffer, wd_size)
5032 unsigned char *buffer;
5036 int set_word_size = BITS_PER_UNIT;
5037 int bit_size = wd_size * set_word_size;
5039 unsigned char *bytep = buffer;
5040 char *bit_buffer = (char *) alloca(bit_size);
5041 tree non_const_bits = get_set_constructor_bits (init, bit_buffer, bit_size);
5043 for (i = 0; i < wd_size; i++)
5046 for (i = 0; i < bit_size; i++)
5050 if (BYTES_BIG_ENDIAN)
5051 *bytep |= (1 << (set_word_size - 1 - bit_pos));
5053 *bytep |= 1 << bit_pos;
5056 if (bit_pos >= set_word_size)
5057 bit_pos = 0, bytep++;
5059 return non_const_bits;
5062 #ifdef ENABLE_CHECKING
5064 /* Complain if the tree code does not match the expected one.
5065 NODE is the tree node in question, CODE is the expected tree code,
5066 and FILE and LINE are the filename and line number, respectively,
5067 of the line on which the check was done. If NONFATAL is nonzero,
5068 don't abort if the reference is invalid; instead, return 0.
5069 If the reference is valid, return NODE. */
5072 tree_check (node, code, file, line, nofatal)
5074 enum tree_code code;
5079 if (TREE_CODE (node) == code)
5084 fatal ("%s:%d: Expect %s, have %s\n", file, line,
5085 tree_code_name[code], tree_code_name[TREE_CODE (node)]);
5088 /* Similar to above, except that we check for a class of tree
5089 code, given in CL. */
5092 tree_class_check (node, cl, file, line, nofatal)
5099 if (TREE_CODE_CLASS (TREE_CODE (node)) == cl)
5104 fatal ("%s:%d: Expect '%c', have '%s'\n", file, line,
5105 cl, tree_code_name[TREE_CODE (node)]);
5108 /* Likewise, but complain if the tree node is not an expression. */
5111 expr_check (node, ignored, file, line, nofatal)
5118 switch (TREE_CODE_CLASS (TREE_CODE (node)))
5132 fatal ("%s:%d: Expect expression, have '%s'\n", file, line,
5133 tree_code_name[TREE_CODE (node)]);
5140 /* Return the alias set for T, which may be either a type or an
5147 if (!flag_strict_aliasing || !lang_get_alias_set)
5148 /* If we're not doing any lanaguage-specific alias analysis, just
5149 assume everything aliases everything else. */
5152 return (*lang_get_alias_set) (t);
5155 /* Return a brand-new alias set. */
5160 static int last_alias_set;
5161 if (flag_strict_aliasing)
5162 return ++last_alias_set;