1 /* Language-independent node constructors for parse phase of GNU compiler.
2 Copyright (C) 1987, 1988, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
3 1999, 2000 Free Software Foundation, Inc.
5 This file is part of GNU CC.
7 GNU CC is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 2, or (at your option)
12 GNU CC is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with GNU CC; see the file COPYING. If not, write to
19 the Free Software Foundation, 59 Temple Place - Suite 330,
20 Boston, MA 02111-1307, USA. */
23 /* This file contains the low level primitives for operating on tree nodes,
24 including allocation, list operations, interning of identifiers,
25 construction of data type nodes and statement nodes,
26 and construction of type conversion nodes. It also contains
27 tables index by tree code that describe how to take apart
30 It is intended to be language-independent, but occasionally
31 calls language-dependent routines defined (for C) in typecheck.c.
33 The low-level allocation routines oballoc and permalloc
34 are used also for allocating many other kinds of objects
35 by all passes of the compiler. */
49 #define obstack_chunk_alloc xmalloc
50 #define obstack_chunk_free free
51 /* obstack.[ch] explicitly declined to prototype this. */
52 extern int _obstack_allocated_p
PARAMS ((struct obstack
*h
, PTR obj
));
54 static void unsave_expr_now_r
PARAMS ((tree
));
56 /* Tree nodes of permanent duration are allocated in this obstack.
57 They are the identifier nodes, and everything outside of
58 the bodies and parameters of function definitions. */
60 struct obstack permanent_obstack
;
62 /* The initial RTL, and all ..._TYPE nodes, in a function
63 are allocated in this obstack. Usually they are freed at the
64 end of the function, but if the function is inline they are saved.
65 For top-level functions, this is maybepermanent_obstack.
66 Separate obstacks are made for nested functions. */
68 struct obstack
*function_maybepermanent_obstack
;
70 /* This is the function_maybepermanent_obstack for top-level functions. */
72 struct obstack maybepermanent_obstack
;
74 /* The contents of the current function definition are allocated
75 in this obstack, and all are freed at the end of the function.
76 For top-level functions, this is temporary_obstack.
77 Separate obstacks are made for nested functions. */
79 struct obstack
*function_obstack
;
81 /* This is used for reading initializers of global variables. */
83 struct obstack temporary_obstack
;
85 /* The tree nodes of an expression are allocated
86 in this obstack, and all are freed at the end of the expression. */
88 struct obstack momentary_obstack
;
90 /* The tree nodes of a declarator are allocated
91 in this obstack, and all are freed when the declarator
94 static struct obstack temp_decl_obstack
;
96 /* This points at either permanent_obstack
97 or the current function_maybepermanent_obstack. */
99 struct obstack
*saveable_obstack
;
101 /* This is same as saveable_obstack during parse and expansion phase;
102 it points to the current function's obstack during optimization.
103 This is the obstack to be used for creating rtl objects. */
105 struct obstack
*rtl_obstack
;
107 /* This points at either permanent_obstack or the current function_obstack. */
109 struct obstack
*current_obstack
;
111 /* This points at either permanent_obstack or the current function_obstack
112 or momentary_obstack. */
114 struct obstack
*expression_obstack
;
116 /* Stack of obstack selections for push_obstacks and pop_obstacks. */
120 struct obstack_stack
*next
;
121 struct obstack
*current
;
122 struct obstack
*saveable
;
123 struct obstack
*expression
;
127 struct obstack_stack
*obstack_stack
;
129 /* Obstack for allocating struct obstack_stack entries. */
131 static struct obstack obstack_stack_obstack
;
133 /* Addresses of first objects in some obstacks.
134 This is for freeing their entire contents. */
135 char *maybepermanent_firstobj
;
136 char *temporary_firstobj
;
137 char *momentary_firstobj
;
138 char *temp_decl_firstobj
;
140 /* This is used to preserve objects (mainly array initializers) that need to
141 live until the end of the current function, but no further. */
142 char *momentary_function_firstobj
;
144 /* Nonzero means all ..._TYPE nodes should be allocated permanently. */
146 int all_types_permanent
;
148 /* Stack of places to restore the momentary obstack back to. */
150 struct momentary_level
152 /* Pointer back to previous such level. */
153 struct momentary_level
*prev
;
154 /* First object allocated within this level. */
156 /* Value of expression_obstack saved at entry to this level. */
157 struct obstack
*obstack
;
160 struct momentary_level
*momentary_stack
;
162 /* Table indexed by tree code giving a string containing a character
163 classifying the tree code. Possibilities are
164 t, d, s, c, r, <, 1, 2 and e. See tree.def for details. */
166 #define DEFTREECODE(SYM, NAME, TYPE, LENGTH) TYPE,
168 char tree_code_type
[MAX_TREE_CODES
] = {
173 /* Table indexed by tree code giving number of expression
174 operands beyond the fixed part of the node structure.
175 Not used for types or decls. */
177 #define DEFTREECODE(SYM, NAME, TYPE, LENGTH) LENGTH,
179 int tree_code_length
[MAX_TREE_CODES
] = {
184 /* Names of tree components.
185 Used for printing out the tree and error messages. */
186 #define DEFTREECODE(SYM, NAME, TYPE, LEN) NAME,
188 const char *tree_code_name
[MAX_TREE_CODES
] = {
193 /* Statistics-gathering stuff. */
214 int tree_node_counts
[(int)all_kinds
];
215 int tree_node_sizes
[(int)all_kinds
];
216 int id_string_size
= 0;
218 static const char * const tree_node_kind_names
[] = {
236 /* Hash table for uniquizing IDENTIFIER_NODEs by name. */
238 #define MAX_HASH_TABLE 1009
239 static tree hash_table
[MAX_HASH_TABLE
]; /* id hash buckets */
241 /* 0 while creating built-in identifiers. */
242 static int do_identifier_warnings
;
244 /* Unique id for next decl created. */
245 static int next_decl_uid
;
246 /* Unique id for next type created. */
247 static int next_type_uid
= 1;
249 /* The language-specific function for alias analysis. If NULL, the
250 language does not do any special alias analysis. */
251 int (*lang_get_alias_set
) PARAMS ((tree
));
253 /* Here is how primitive or already-canonicalized types' hash
255 #define TYPE_HASH(TYPE) ((unsigned long) (TYPE) & 0777777)
257 /* Since we cannot rehash a type after it is in the table, we have to
258 keep the hash code. */
266 /* Initial size of the hash table (rounded to next prime). */
267 #define TYPE_HASH_INITIAL_SIZE 1000
269 /* Now here is the hash table. When recording a type, it is added to
270 the slot whose index is the hash code. Note that the hash table is
271 used for several kinds of types (function types, array types and
272 array index range types, for now). While all these live in the
273 same table, they are completely independent, and the hash code is
274 computed differently for each of these. */
276 htab_t type_hash_table
;
278 static void build_real_from_int_cst_1
PARAMS ((PTR
));
279 static void set_type_quals
PARAMS ((tree
, int));
280 static void append_random_chars
PARAMS ((char *));
281 static void mark_type_hash
PARAMS ((void *));
282 static int type_hash_eq
PARAMS ((const void*, const void*));
283 static unsigned int type_hash_hash
PARAMS ((const void*));
284 static void print_type_hash_statistics
PARAMS((void));
285 static int mark_hash_entry
PARAMS((void **, void *));
287 /* If non-null, these are language-specific helper functions for
288 unsave_expr_now. If present, LANG_UNSAVE is called before its
289 argument (an UNSAVE_EXPR) is to be unsaved, and all other
290 processing in unsave_expr_now is aborted. LANG_UNSAVE_EXPR_NOW is
291 called from unsave_expr_1 for language-specific tree codes. */
292 void (*lang_unsave
) PARAMS ((tree
*));
293 void (*lang_unsave_expr_now
) PARAMS ((tree
));
295 /* The string used as a placeholder instead of a source file name for
296 built-in tree nodes. The variable, which is dynamically allocated,
297 should be used; the macro is only used to initialize it. */
299 static char *built_in_filename
;
300 #define BUILT_IN_FILENAME ("<built-in>")
302 tree global_trees
[TI_MAX
];
303 tree integer_types
[itk_none
];
305 /* Init the principal obstacks. */
310 gcc_obstack_init (&obstack_stack_obstack
);
311 gcc_obstack_init (&permanent_obstack
);
313 gcc_obstack_init (&temporary_obstack
);
314 temporary_firstobj
= (char *) obstack_alloc (&temporary_obstack
, 0);
315 gcc_obstack_init (&momentary_obstack
);
316 momentary_firstobj
= (char *) obstack_alloc (&momentary_obstack
, 0);
317 momentary_function_firstobj
= momentary_firstobj
;
318 gcc_obstack_init (&maybepermanent_obstack
);
319 maybepermanent_firstobj
320 = (char *) obstack_alloc (&maybepermanent_obstack
, 0);
321 gcc_obstack_init (&temp_decl_obstack
);
322 temp_decl_firstobj
= (char *) obstack_alloc (&temp_decl_obstack
, 0);
324 function_obstack
= &temporary_obstack
;
325 function_maybepermanent_obstack
= &maybepermanent_obstack
;
326 current_obstack
= &permanent_obstack
;
327 expression_obstack
= &permanent_obstack
;
328 rtl_obstack
= saveable_obstack
= &permanent_obstack
;
330 /* Init the hash table of identifiers. */
331 bzero ((char *) hash_table
, sizeof hash_table
);
332 ggc_add_tree_root (hash_table
, sizeof hash_table
/ sizeof (tree
));
334 /* Initialize the hash table of types. */
335 type_hash_table
= htab_create (TYPE_HASH_INITIAL_SIZE
, type_hash_hash
,
337 ggc_add_root (&type_hash_table
, 1, sizeof type_hash_table
, mark_type_hash
);
338 ggc_add_tree_root (global_trees
, TI_MAX
);
339 ggc_add_tree_root (integer_types
, itk_none
);
343 gcc_obstack_init (obstack
)
344 struct obstack
*obstack
;
346 /* Let particular systems override the size of a chunk. */
347 #ifndef OBSTACK_CHUNK_SIZE
348 #define OBSTACK_CHUNK_SIZE 0
350 /* Let them override the alloc and free routines too. */
351 #ifndef OBSTACK_CHUNK_ALLOC
352 #define OBSTACK_CHUNK_ALLOC xmalloc
354 #ifndef OBSTACK_CHUNK_FREE
355 #define OBSTACK_CHUNK_FREE free
357 _obstack_begin (obstack
, OBSTACK_CHUNK_SIZE
, 0,
358 (void *(*) PARAMS ((long))) OBSTACK_CHUNK_ALLOC
,
359 (void (*) PARAMS ((void *))) OBSTACK_CHUNK_FREE
);
362 /* Save all variables describing the current status into the structure
363 *P. This function is called whenever we start compiling one
364 function in the midst of compiling another. For example, when
365 compiling a nested function, or, in C++, a template instantiation
366 that is required by the function we are currently compiling.
368 CONTEXT is the decl_function_context for the function we're about to
369 compile; if it isn't current_function_decl, we have to play some games. */
375 p
->all_types_permanent
= all_types_permanent
;
376 p
->momentary_stack
= momentary_stack
;
377 p
->maybepermanent_firstobj
= maybepermanent_firstobj
;
378 p
->temporary_firstobj
= temporary_firstobj
;
379 p
->momentary_firstobj
= momentary_firstobj
;
380 p
->momentary_function_firstobj
= momentary_function_firstobj
;
381 p
->function_obstack
= function_obstack
;
382 p
->function_maybepermanent_obstack
= function_maybepermanent_obstack
;
383 p
->current_obstack
= current_obstack
;
384 p
->expression_obstack
= expression_obstack
;
385 p
->saveable_obstack
= saveable_obstack
;
386 p
->rtl_obstack
= rtl_obstack
;
388 function_maybepermanent_obstack
389 = (struct obstack
*) xmalloc (sizeof (struct obstack
));
390 gcc_obstack_init (function_maybepermanent_obstack
);
391 maybepermanent_firstobj
392 = (char *) obstack_finish (function_maybepermanent_obstack
);
394 function_obstack
= (struct obstack
*) xmalloc (sizeof (struct obstack
));
395 gcc_obstack_init (function_obstack
);
397 current_obstack
= &permanent_obstack
;
398 expression_obstack
= &permanent_obstack
;
399 rtl_obstack
= saveable_obstack
= &permanent_obstack
;
401 temporary_firstobj
= (char *) obstack_alloc (&temporary_obstack
, 0);
402 momentary_firstobj
= (char *) obstack_finish (&momentary_obstack
);
403 momentary_function_firstobj
= momentary_firstobj
;
406 /* Restore all variables describing the current status from the structure *P.
407 This is used after a nested function. */
410 restore_tree_status (p
)
413 all_types_permanent
= p
->all_types_permanent
;
414 momentary_stack
= p
->momentary_stack
;
416 obstack_free (&momentary_obstack
, momentary_function_firstobj
);
418 /* Free saveable storage used by the function just compiled and not
420 obstack_free (function_maybepermanent_obstack
, maybepermanent_firstobj
);
421 if (obstack_empty_p (function_maybepermanent_obstack
))
423 obstack_free (function_maybepermanent_obstack
, NULL
);
424 free (function_maybepermanent_obstack
);
427 obstack_free (&temporary_obstack
, temporary_firstobj
);
428 obstack_free (&momentary_obstack
, momentary_function_firstobj
);
430 obstack_free (function_obstack
, NULL
);
431 free (function_obstack
);
433 temporary_firstobj
= p
->temporary_firstobj
;
434 momentary_firstobj
= p
->momentary_firstobj
;
435 momentary_function_firstobj
= p
->momentary_function_firstobj
;
436 maybepermanent_firstobj
= p
->maybepermanent_firstobj
;
437 function_obstack
= p
->function_obstack
;
438 function_maybepermanent_obstack
= p
->function_maybepermanent_obstack
;
439 current_obstack
= p
->current_obstack
;
440 expression_obstack
= p
->expression_obstack
;
441 saveable_obstack
= p
->saveable_obstack
;
442 rtl_obstack
= p
->rtl_obstack
;
445 /* Start allocating on the temporary (per function) obstack.
446 This is done in start_function before parsing the function body,
447 and before each initialization at top level, and to go back
448 to temporary allocation after doing permanent_allocation. */
451 temporary_allocation ()
453 /* Note that function_obstack at top level points to temporary_obstack.
454 But within a nested function context, it is a separate obstack. */
455 current_obstack
= function_obstack
;
456 expression_obstack
= function_obstack
;
457 rtl_obstack
= saveable_obstack
= function_maybepermanent_obstack
;
461 /* Start allocating on the permanent obstack but don't
462 free the temporary data. After calling this, call
463 `permanent_allocation' to fully resume permanent allocation status. */
466 end_temporary_allocation ()
468 current_obstack
= &permanent_obstack
;
469 expression_obstack
= &permanent_obstack
;
470 rtl_obstack
= saveable_obstack
= &permanent_obstack
;
473 /* Resume allocating on the temporary obstack, undoing
474 effects of `end_temporary_allocation'. */
477 resume_temporary_allocation ()
479 current_obstack
= function_obstack
;
480 expression_obstack
= function_obstack
;
481 rtl_obstack
= saveable_obstack
= function_maybepermanent_obstack
;
484 /* While doing temporary allocation, switch to allocating in such a
485 way as to save all nodes if the function is inlined. Call
486 resume_temporary_allocation to go back to ordinary temporary
490 saveable_allocation ()
492 /* Note that function_obstack at top level points to temporary_obstack.
493 But within a nested function context, it is a separate obstack. */
494 expression_obstack
= current_obstack
= saveable_obstack
;
497 /* Switch to current obstack CURRENT and maybepermanent obstack SAVEABLE,
498 recording the previously current obstacks on a stack.
499 This does not free any storage in any obstack. */
502 push_obstacks (current
, saveable
)
503 struct obstack
*current
, *saveable
;
505 struct obstack_stack
*p
;
507 p
= (struct obstack_stack
*) obstack_alloc (&obstack_stack_obstack
,
508 (sizeof (struct obstack_stack
)));
510 p
->current
= current_obstack
;
511 p
->saveable
= saveable_obstack
;
512 p
->expression
= expression_obstack
;
513 p
->rtl
= rtl_obstack
;
514 p
->next
= obstack_stack
;
517 current_obstack
= current
;
518 expression_obstack
= current
;
519 rtl_obstack
= saveable_obstack
= saveable
;
522 /* Save the current set of obstacks, but don't change them. */
525 push_obstacks_nochange ()
527 struct obstack_stack
*p
;
529 p
= (struct obstack_stack
*) obstack_alloc (&obstack_stack_obstack
,
530 (sizeof (struct obstack_stack
)));
532 p
->current
= current_obstack
;
533 p
->saveable
= saveable_obstack
;
534 p
->expression
= expression_obstack
;
535 p
->rtl
= rtl_obstack
;
536 p
->next
= obstack_stack
;
540 /* Pop the obstack selection stack. */
545 struct obstack_stack
*p
;
548 obstack_stack
= p
->next
;
550 current_obstack
= p
->current
;
551 saveable_obstack
= p
->saveable
;
552 expression_obstack
= p
->expression
;
553 rtl_obstack
= p
->rtl
;
555 obstack_free (&obstack_stack_obstack
, p
);
558 /* Nonzero if temporary allocation is currently in effect.
559 Zero if currently doing permanent allocation. */
562 allocation_temporary_p ()
564 return current_obstack
!= &permanent_obstack
;
567 /* Go back to allocating on the permanent obstack
568 and free everything in the temporary obstack.
570 FUNCTION_END is true only if we have just finished compiling a function.
571 In that case, we also free preserved initial values on the momentary
575 permanent_allocation (function_end
)
578 /* Free up previous temporary obstack data */
579 obstack_free (&temporary_obstack
, temporary_firstobj
);
582 obstack_free (&momentary_obstack
, momentary_function_firstobj
);
583 momentary_firstobj
= momentary_function_firstobj
;
586 obstack_free (&momentary_obstack
, momentary_firstobj
);
588 obstack_free (function_maybepermanent_obstack
, maybepermanent_firstobj
);
589 obstack_free (&temp_decl_obstack
, temp_decl_firstobj
);
591 current_obstack
= &permanent_obstack
;
592 expression_obstack
= &permanent_obstack
;
593 rtl_obstack
= saveable_obstack
= &permanent_obstack
;
596 /* Save permanently everything on the maybepermanent_obstack. */
601 maybepermanent_firstobj
602 = (char *) obstack_alloc (function_maybepermanent_obstack
, 0);
606 preserve_initializer ()
608 struct momentary_level
*tem
;
612 = (char *) obstack_alloc (&temporary_obstack
, 0);
613 maybepermanent_firstobj
614 = (char *) obstack_alloc (function_maybepermanent_obstack
, 0);
616 old_momentary
= momentary_firstobj
;
618 = (char *) obstack_alloc (&momentary_obstack
, 0);
619 if (momentary_firstobj
!= old_momentary
)
620 for (tem
= momentary_stack
; tem
; tem
= tem
->prev
)
621 tem
->base
= momentary_firstobj
;
624 /* Start allocating new rtl in current_obstack.
625 Use resume_temporary_allocation
626 to go back to allocating rtl in saveable_obstack. */
629 rtl_in_current_obstack ()
631 rtl_obstack
= current_obstack
;
634 /* Start allocating rtl from saveable_obstack. Intended to be used after
635 a call to push_obstacks_nochange. */
638 rtl_in_saveable_obstack ()
640 rtl_obstack
= saveable_obstack
;
643 /* Allocate SIZE bytes in the current obstack
644 and return a pointer to them.
645 In practice the current obstack is always the temporary one. */
651 return (char *) obstack_alloc (current_obstack
, size
);
654 /* Free the object PTR in the current obstack
655 as well as everything allocated since PTR.
656 In practice the current obstack is always the temporary one. */
662 obstack_free (current_obstack
, ptr
);
665 /* Allocate SIZE bytes in the permanent obstack
666 and return a pointer to them. */
672 return (char *) obstack_alloc (&permanent_obstack
, size
);
675 /* Allocate NELEM items of SIZE bytes in the permanent obstack
676 and return a pointer to them. The storage is cleared before
677 returning the value. */
680 perm_calloc (nelem
, size
)
684 char *rval
= (char *) obstack_alloc (&permanent_obstack
, nelem
* size
);
685 bzero (rval
, nelem
* size
);
689 /* Allocate SIZE bytes in the saveable obstack
690 and return a pointer to them. */
696 return (char *) obstack_alloc (saveable_obstack
, size
);
699 /* Allocate SIZE bytes in the expression obstack
700 and return a pointer to them. */
706 return (char *) obstack_alloc (expression_obstack
, size
);
709 /* Print out which obstack an object is in. */
712 print_obstack_name (object
, file
, prefix
)
717 struct obstack
*obstack
= NULL
;
718 const char *obstack_name
= NULL
;
721 for (p
= outer_function_chain
; p
; p
= p
->next
)
723 if (_obstack_allocated_p (p
->function_obstack
, object
))
725 obstack
= p
->function_obstack
;
726 obstack_name
= "containing function obstack";
728 if (_obstack_allocated_p (p
->function_maybepermanent_obstack
, object
))
730 obstack
= p
->function_maybepermanent_obstack
;
731 obstack_name
= "containing function maybepermanent obstack";
735 if (_obstack_allocated_p (&obstack_stack_obstack
, object
))
737 obstack
= &obstack_stack_obstack
;
738 obstack_name
= "obstack_stack_obstack";
740 else if (_obstack_allocated_p (function_obstack
, object
))
742 obstack
= function_obstack
;
743 obstack_name
= "function obstack";
745 else if (_obstack_allocated_p (&permanent_obstack
, object
))
747 obstack
= &permanent_obstack
;
748 obstack_name
= "permanent_obstack";
750 else if (_obstack_allocated_p (&momentary_obstack
, object
))
752 obstack
= &momentary_obstack
;
753 obstack_name
= "momentary_obstack";
755 else if (_obstack_allocated_p (function_maybepermanent_obstack
, object
))
757 obstack
= function_maybepermanent_obstack
;
758 obstack_name
= "function maybepermanent obstack";
760 else if (_obstack_allocated_p (&temp_decl_obstack
, object
))
762 obstack
= &temp_decl_obstack
;
763 obstack_name
= "temp_decl_obstack";
766 /* Check to see if the object is in the free area of the obstack. */
769 if (object
>= obstack
->next_free
770 && object
< obstack
->chunk_limit
)
771 fprintf (file
, "%s in free portion of obstack %s",
772 prefix
, obstack_name
);
774 fprintf (file
, "%s allocated from %s", prefix
, obstack_name
);
777 fprintf (file
, "%s not allocated from any obstack", prefix
);
781 debug_obstack (object
)
784 print_obstack_name (object
, stderr
, "object");
785 fprintf (stderr
, ".\n");
788 /* Return 1 if OBJ is in the permanent obstack.
789 This is slow, and should be used only for debugging.
790 Use TREE_PERMANENT for other purposes. */
793 object_permanent_p (obj
)
796 return _obstack_allocated_p (&permanent_obstack
, obj
);
799 /* Start a level of momentary allocation.
800 In C, each compound statement has its own level
801 and that level is freed at the end of each statement.
802 All expression nodes are allocated in the momentary allocation level. */
807 struct momentary_level
*tem
808 = (struct momentary_level
*) obstack_alloc (&momentary_obstack
,
809 sizeof (struct momentary_level
));
810 tem
->prev
= momentary_stack
;
811 tem
->base
= (char *) obstack_base (&momentary_obstack
);
812 tem
->obstack
= expression_obstack
;
813 momentary_stack
= tem
;
814 expression_obstack
= &momentary_obstack
;
817 /* Set things up so the next clear_momentary will only clear memory
818 past our present position in momentary_obstack. */
821 preserve_momentary ()
823 momentary_stack
->base
= (char *) obstack_base (&momentary_obstack
);
826 /* Free all the storage in the current momentary-allocation level.
827 In C, this happens at the end of each statement. */
832 obstack_free (&momentary_obstack
, momentary_stack
->base
);
835 /* Discard a level of momentary allocation.
836 In C, this happens at the end of each compound statement.
837 Restore the status of expression node allocation
838 that was in effect before this level was created. */
843 struct momentary_level
*tem
= momentary_stack
;
844 momentary_stack
= tem
->prev
;
845 expression_obstack
= tem
->obstack
;
846 /* We can't free TEM from the momentary_obstack, because there might
847 be objects above it which have been saved. We can free back to the
848 stack of the level we are popping off though. */
849 obstack_free (&momentary_obstack
, tem
->base
);
852 /* Pop back to the previous level of momentary allocation,
853 but don't free any momentary data just yet. */
856 pop_momentary_nofree ()
858 struct momentary_level
*tem
= momentary_stack
;
859 momentary_stack
= tem
->prev
;
860 expression_obstack
= tem
->obstack
;
863 /* Call when starting to parse a declaration:
864 make expressions in the declaration last the length of the function.
865 Returns an argument that should be passed to resume_momentary later. */
870 register int tem
= expression_obstack
== &momentary_obstack
;
871 expression_obstack
= saveable_obstack
;
875 /* Call when finished parsing a declaration:
876 restore the treatment of node-allocation that was
877 in effect before the suspension.
878 YES should be the value previously returned by suspend_momentary. */
881 resume_momentary (yes
)
885 expression_obstack
= &momentary_obstack
;
888 /* Init the tables indexed by tree code.
889 Note that languages can add to these tables to define their own codes. */
895 = ggc_alloc_string (BUILT_IN_FILENAME
, sizeof (BUILT_IN_FILENAME
));
896 ggc_add_string_root (&built_in_filename
, 1);
899 /* Return a newly allocated node of code CODE.
900 Initialize the node's unique id and its TREE_PERMANENT flag.
901 Note that if garbage collection is in use, TREE_PERMANENT will
902 always be zero - we want to eliminate use of TREE_PERMANENT.
903 For decl and type nodes, some other fields are initialized.
904 The rest of the node is initialized to zero.
906 Achoo! I got a code in the node. */
913 register int type
= TREE_CODE_CLASS (code
);
914 register int length
= 0;
915 register struct obstack
*obstack
= current_obstack
;
916 #ifdef GATHER_STATISTICS
917 register tree_node_kind kind
;
922 case 'd': /* A decl node */
923 #ifdef GATHER_STATISTICS
926 length
= sizeof (struct tree_decl
);
927 /* All decls in an inline function need to be saved. */
928 if (obstack
!= &permanent_obstack
)
929 obstack
= saveable_obstack
;
931 /* PARM_DECLs go on the context of the parent. If this is a nested
932 function, then we must allocate the PARM_DECL on the parent's
933 obstack, so that they will live to the end of the parent's
934 closing brace. This is necessary in case we try to inline the
935 function into its parent.
937 PARM_DECLs of top-level functions do not have this problem. However,
938 we allocate them where we put the FUNCTION_DECL for languages such as
939 Ada that need to consult some flags in the PARM_DECLs of the function
942 See comment in restore_tree_status for why we can't put this
943 in function_obstack. */
944 if (code
== PARM_DECL
&& obstack
!= &permanent_obstack
)
947 if (current_function_decl
)
948 context
= decl_function_context (current_function_decl
);
952 = find_function_data (context
)->function_maybepermanent_obstack
;
956 case 't': /* a type node */
957 #ifdef GATHER_STATISTICS
960 length
= sizeof (struct tree_type
);
961 /* All data types are put where we can preserve them if nec. */
962 if (obstack
!= &permanent_obstack
)
963 obstack
= all_types_permanent
? &permanent_obstack
: saveable_obstack
;
966 case 'b': /* a lexical block */
967 #ifdef GATHER_STATISTICS
970 length
= sizeof (struct tree_block
);
971 /* All BLOCK nodes are put where we can preserve them if nec. */
972 if (obstack
!= &permanent_obstack
)
973 obstack
= saveable_obstack
;
976 case 's': /* an expression with side effects */
977 #ifdef GATHER_STATISTICS
981 case 'r': /* a reference */
982 #ifdef GATHER_STATISTICS
986 case 'e': /* an expression */
987 case '<': /* a comparison expression */
988 case '1': /* a unary arithmetic expression */
989 case '2': /* a binary arithmetic expression */
990 #ifdef GATHER_STATISTICS
994 obstack
= expression_obstack
;
995 /* All BIND_EXPR nodes are put where we can preserve them if nec. */
996 if (code
== BIND_EXPR
&& obstack
!= &permanent_obstack
)
997 obstack
= saveable_obstack
;
998 length
= sizeof (struct tree_exp
)
999 + (tree_code_length
[(int) code
] - 1) * sizeof (char *);
1002 case 'c': /* a constant */
1003 #ifdef GATHER_STATISTICS
1006 obstack
= expression_obstack
;
1008 /* We can't use tree_code_length for INTEGER_CST, since the number of
1009 words is machine-dependent due to varying length of HOST_WIDE_INT,
1010 which might be wider than a pointer (e.g., long long). Similarly
1011 for REAL_CST, since the number of words is machine-dependent due
1012 to varying size and alignment of `double'. */
1014 if (code
== INTEGER_CST
)
1015 length
= sizeof (struct tree_int_cst
);
1016 else if (code
== REAL_CST
)
1017 length
= sizeof (struct tree_real_cst
);
1019 length
= sizeof (struct tree_common
)
1020 + tree_code_length
[(int) code
] * sizeof (char *);
1023 case 'x': /* something random, like an identifier. */
1024 #ifdef GATHER_STATISTICS
1025 if (code
== IDENTIFIER_NODE
)
1027 else if (code
== OP_IDENTIFIER
)
1029 else if (code
== TREE_VEC
)
1034 length
= sizeof (struct tree_common
)
1035 + tree_code_length
[(int) code
] * sizeof (char *);
1036 /* Identifier nodes are always permanent since they are
1037 unique in a compiler run. */
1038 if (code
== IDENTIFIER_NODE
) obstack
= &permanent_obstack
;
1046 t
= ggc_alloc_tree (length
);
1049 t
= (tree
) obstack_alloc (obstack
, length
);
1050 memset ((PTR
) t
, 0, length
);
1053 #ifdef GATHER_STATISTICS
1054 tree_node_counts
[(int)kind
]++;
1055 tree_node_sizes
[(int)kind
] += length
;
1058 TREE_SET_CODE (t
, code
);
1059 TREE_SET_PERMANENT (t
);
1064 TREE_SIDE_EFFECTS (t
) = 1;
1065 TREE_TYPE (t
) = void_type_node
;
1069 if (code
!= FUNCTION_DECL
)
1071 DECL_IN_SYSTEM_HEADER (t
) = in_system_header
;
1072 DECL_SOURCE_LINE (t
) = lineno
;
1073 DECL_SOURCE_FILE (t
) =
1074 (input_filename
) ? input_filename
: built_in_filename
;
1075 DECL_UID (t
) = next_decl_uid
++;
1076 /* Note that we have not yet computed the alias set for this
1078 DECL_POINTER_ALIAS_SET (t
) = -1;
1082 TYPE_UID (t
) = next_type_uid
++;
1084 TYPE_MAIN_VARIANT (t
) = t
;
1085 TYPE_OBSTACK (t
) = obstack
;
1086 TYPE_ATTRIBUTES (t
) = NULL_TREE
;
1087 #ifdef SET_DEFAULT_TYPE_ATTRIBUTES
1088 SET_DEFAULT_TYPE_ATTRIBUTES (t
);
1090 /* Note that we have not yet computed the alias set for this
1092 TYPE_ALIAS_SET (t
) = -1;
1096 TREE_CONSTANT (t
) = 1;
1106 case PREDECREMENT_EXPR
:
1107 case PREINCREMENT_EXPR
:
1108 case POSTDECREMENT_EXPR
:
1109 case POSTINCREMENT_EXPR
:
1110 /* All of these have side-effects, no matter what their
1112 TREE_SIDE_EFFECTS (t
) = 1;
1124 /* A front-end can reset this to an appropriate function if types need
1125 special handling. */
1127 tree (*make_lang_type_fn
) PARAMS ((enum tree_code
)) = make_node
;
1129 /* Return a new type (with the indicated CODE), doing whatever
1130 language-specific processing is required. */
1133 make_lang_type (code
)
1134 enum tree_code code
;
1136 return (*make_lang_type_fn
) (code
);
1139 /* Return a new node with the same contents as NODE except that its
1140 TREE_CHAIN is zero and it has a fresh uid. Unlike make_node, this
1141 function always performs the allocation on the CURRENT_OBSTACK;
1142 it's up to the caller to pick the right obstack before calling this
1150 register enum tree_code code
= TREE_CODE (node
);
1151 register int length
= 0;
1153 switch (TREE_CODE_CLASS (code
))
1155 case 'd': /* A decl node */
1156 length
= sizeof (struct tree_decl
);
1159 case 't': /* a type node */
1160 length
= sizeof (struct tree_type
);
1163 case 'b': /* a lexical block node */
1164 length
= sizeof (struct tree_block
);
1167 case 'r': /* a reference */
1168 case 'e': /* an expression */
1169 case 's': /* an expression with side effects */
1170 case '<': /* a comparison expression */
1171 case '1': /* a unary arithmetic expression */
1172 case '2': /* a binary arithmetic expression */
1173 length
= sizeof (struct tree_exp
)
1174 + (tree_code_length
[(int) code
] - 1) * sizeof (char *);
1177 case 'c': /* a constant */
1178 /* We can't use tree_code_length for INTEGER_CST, since the number of
1179 words is machine-dependent due to varying length of HOST_WIDE_INT,
1180 which might be wider than a pointer (e.g., long long). Similarly
1181 for REAL_CST, since the number of words is machine-dependent due
1182 to varying size and alignment of `double'. */
1183 if (code
== INTEGER_CST
)
1184 length
= sizeof (struct tree_int_cst
);
1185 else if (code
== REAL_CST
)
1186 length
= sizeof (struct tree_real_cst
);
1188 length
= (sizeof (struct tree_common
)
1189 + tree_code_length
[(int) code
] * sizeof (char *));
1192 case 'x': /* something random, like an identifier. */
1193 length
= sizeof (struct tree_common
)
1194 + tree_code_length
[(int) code
] * sizeof (char *);
1195 if (code
== TREE_VEC
)
1196 length
+= (TREE_VEC_LENGTH (node
) - 1) * sizeof (char *);
1200 t
= ggc_alloc_tree (length
);
1202 t
= (tree
) obstack_alloc (current_obstack
, length
);
1203 memcpy (t
, node
, length
);
1206 TREE_ASM_WRITTEN (t
) = 0;
1208 if (TREE_CODE_CLASS (code
) == 'd')
1209 DECL_UID (t
) = next_decl_uid
++;
1210 else if (TREE_CODE_CLASS (code
) == 't')
1212 TYPE_UID (t
) = next_type_uid
++;
1213 TYPE_OBSTACK (t
) = current_obstack
;
1215 /* The following is so that the debug code for
1216 the copy is different from the original type.
1217 The two statements usually duplicate each other
1218 (because they clear fields of the same union),
1219 but the optimizer should catch that. */
1220 TYPE_SYMTAB_POINTER (t
) = 0;
1221 TYPE_SYMTAB_ADDRESS (t
) = 0;
1224 TREE_SET_PERMANENT (t
);
1229 /* Return a copy of a chain of nodes, chained through the TREE_CHAIN field.
1230 For example, this can copy a list made of TREE_LIST nodes. */
1237 register tree prev
, next
;
1242 head
= prev
= copy_node (list
);
1243 next
= TREE_CHAIN (list
);
1246 TREE_CHAIN (prev
) = copy_node (next
);
1247 prev
= TREE_CHAIN (prev
);
1248 next
= TREE_CHAIN (next
);
1255 /* Return an IDENTIFIER_NODE whose name is TEXT (a null-terminated string).
1256 If an identifier with that name has previously been referred to,
1257 the same node is returned this time. */
1260 get_identifier (text
)
1261 register const char *text
;
1266 register int len
, hash_len
;
1268 /* Compute length of text in len. */
1269 len
= strlen (text
);
1271 /* Decide how much of that length to hash on */
1273 if (warn_id_clash
&& len
> id_clash_len
)
1274 hash_len
= id_clash_len
;
1276 /* Compute hash code */
1277 hi
= hash_len
* 613 + (unsigned) text
[0];
1278 for (i
= 1; i
< hash_len
; i
+= 2)
1279 hi
= ((hi
* 613) + (unsigned) (text
[i
]));
1281 hi
&= (1 << HASHBITS
) - 1;
1282 hi
%= MAX_HASH_TABLE
;
1284 /* Search table for identifier */
1285 for (idp
= hash_table
[hi
]; idp
; idp
= TREE_CHAIN (idp
))
1286 if (IDENTIFIER_LENGTH (idp
) == len
1287 && IDENTIFIER_POINTER (idp
)[0] == text
[0]
1288 && !bcmp (IDENTIFIER_POINTER (idp
), text
, len
))
1289 return idp
; /* <-- return if found */
1291 /* Not found; optionally warn about a similar identifier */
1292 if (warn_id_clash
&& do_identifier_warnings
&& len
>= id_clash_len
)
1293 for (idp
= hash_table
[hi
]; idp
; idp
= TREE_CHAIN (idp
))
1294 if (!strncmp (IDENTIFIER_POINTER (idp
), text
, id_clash_len
))
1296 warning ("`%s' and `%s' identical in first %d characters",
1297 IDENTIFIER_POINTER (idp
), text
, id_clash_len
);
1301 if (tree_code_length
[(int) IDENTIFIER_NODE
] < 0)
1302 abort (); /* set_identifier_size hasn't been called. */
1304 /* Not found, create one, add to chain */
1305 idp
= make_node (IDENTIFIER_NODE
);
1306 IDENTIFIER_LENGTH (idp
) = len
;
1307 #ifdef GATHER_STATISTICS
1308 id_string_size
+= len
;
1312 IDENTIFIER_POINTER (idp
) = ggc_alloc_string (text
, len
);
1314 IDENTIFIER_POINTER (idp
) = obstack_copy0 (&permanent_obstack
, text
, len
);
1316 TREE_CHAIN (idp
) = hash_table
[hi
];
1317 hash_table
[hi
] = idp
;
1318 return idp
; /* <-- return if created */
1321 /* If an identifier with the name TEXT (a null-terminated string) has
1322 previously been referred to, return that node; otherwise return
1326 maybe_get_identifier (text
)
1327 register const char *text
;
1332 register int len
, hash_len
;
1334 /* Compute length of text in len. */
1335 len
= strlen (text
);
1337 /* Decide how much of that length to hash on */
1339 if (warn_id_clash
&& len
> id_clash_len
)
1340 hash_len
= id_clash_len
;
1342 /* Compute hash code */
1343 hi
= hash_len
* 613 + (unsigned) text
[0];
1344 for (i
= 1; i
< hash_len
; i
+= 2)
1345 hi
= ((hi
* 613) + (unsigned) (text
[i
]));
1347 hi
&= (1 << HASHBITS
) - 1;
1348 hi
%= MAX_HASH_TABLE
;
1350 /* Search table for identifier */
1351 for (idp
= hash_table
[hi
]; idp
; idp
= TREE_CHAIN (idp
))
1352 if (IDENTIFIER_LENGTH (idp
) == len
1353 && IDENTIFIER_POINTER (idp
)[0] == text
[0]
1354 && !bcmp (IDENTIFIER_POINTER (idp
), text
, len
))
1355 return idp
; /* <-- return if found */
1360 /* Enable warnings on similar identifiers (if requested).
1361 Done after the built-in identifiers are created. */
1364 start_identifier_warnings ()
1366 do_identifier_warnings
= 1;
1369 /* Record the size of an identifier node for the language in use.
1370 SIZE is the total size in bytes.
1371 This is called by the language-specific files. This must be
1372 called before allocating any identifiers. */
1375 set_identifier_size (size
)
1378 tree_code_length
[(int) IDENTIFIER_NODE
]
1379 = (size
- sizeof (struct tree_common
)) / sizeof (tree
);
1382 /* Return a newly constructed INTEGER_CST node whose constant value
1383 is specified by the two ints LOW and HI.
1384 The TREE_TYPE is set to `int'.
1386 This function should be used via the `build_int_2' macro. */
1389 build_int_2_wide (low
, hi
)
1390 unsigned HOST_WIDE_INT low
;
1393 register tree t
= make_node (INTEGER_CST
);
1395 TREE_INT_CST_LOW (t
) = low
;
1396 TREE_INT_CST_HIGH (t
) = hi
;
1397 TREE_TYPE (t
) = integer_type_node
;
1401 /* Return a new REAL_CST node whose type is TYPE and value is D. */
1404 build_real (type
, d
)
1411 /* Check for valid float value for this type on this target machine;
1412 if not, can print error message and store a valid value in D. */
1413 #ifdef CHECK_FLOAT_VALUE
1414 CHECK_FLOAT_VALUE (TYPE_MODE (type
), d
, overflow
);
1417 v
= make_node (REAL_CST
);
1418 TREE_TYPE (v
) = type
;
1419 TREE_REAL_CST (v
) = d
;
1420 TREE_OVERFLOW (v
) = TREE_CONSTANT_OVERFLOW (v
) = overflow
;
1424 /* Return a new REAL_CST node whose type is TYPE
1425 and whose value is the integer value of the INTEGER_CST node I. */
1427 #if !defined (REAL_IS_NOT_DOUBLE) || defined (REAL_ARITHMETIC)
1430 real_value_from_int_cst (type
, i
)
1431 tree type ATTRIBUTE_UNUSED
, i
;
1435 #ifdef REAL_ARITHMETIC
1436 /* Clear all bits of the real value type so that we can later do
1437 bitwise comparisons to see if two values are the same. */
1438 bzero ((char *) &d
, sizeof d
);
1440 if (! TREE_UNSIGNED (TREE_TYPE (i
)))
1441 REAL_VALUE_FROM_INT (d
, TREE_INT_CST_LOW (i
), TREE_INT_CST_HIGH (i
),
1444 REAL_VALUE_FROM_UNSIGNED_INT (d
, TREE_INT_CST_LOW (i
),
1445 TREE_INT_CST_HIGH (i
), TYPE_MODE (type
));
1446 #else /* not REAL_ARITHMETIC */
1447 /* Some 386 compilers mishandle unsigned int to float conversions,
1448 so introduce a temporary variable E to avoid those bugs. */
1449 if (TREE_INT_CST_HIGH (i
) < 0 && ! TREE_UNSIGNED (TREE_TYPE (i
)))
1453 d
= (double) (~ TREE_INT_CST_HIGH (i
));
1454 e
= ((double) ((HOST_WIDE_INT
) 1 << (HOST_BITS_PER_WIDE_INT
/ 2))
1455 * (double) ((HOST_WIDE_INT
) 1 << (HOST_BITS_PER_WIDE_INT
/ 2)));
1457 e
= (double) (~ TREE_INT_CST_LOW (i
));
1465 d
= (double) (unsigned HOST_WIDE_INT
) TREE_INT_CST_HIGH (i
);
1466 e
= ((double) ((HOST_WIDE_INT
) 1 << (HOST_BITS_PER_WIDE_INT
/ 2))
1467 * (double) ((HOST_WIDE_INT
) 1 << (HOST_BITS_PER_WIDE_INT
/ 2)));
1469 e
= (double) TREE_INT_CST_LOW (i
);
1472 #endif /* not REAL_ARITHMETIC */
1476 /* Args to pass to and from build_real_from_int_cst_1. */
1480 tree type
; /* Input: type to conver to. */
1481 tree i
; /* Input: operand to convert */
1482 REAL_VALUE_TYPE d
; /* Output: floating point value. */
1485 /* Convert an integer to a floating point value while protected by a floating
1486 point exception handler. */
1489 build_real_from_int_cst_1 (data
)
1492 struct brfic_args
*args
= (struct brfic_args
*) data
;
1494 #ifdef REAL_ARITHMETIC
1495 args
->d
= real_value_from_int_cst (args
->type
, args
->i
);
1498 = REAL_VALUE_TRUNCATE (TYPE_MODE (args
->type
),
1499 real_value_from_int_cst (args
->type
, args
->i
));
1503 /* Given a tree representing an integer constant I, return a tree
1504 representing the same value as a floating-point constant of type TYPE.
1505 We cannot perform this operation if there is no way of doing arithmetic
1506 on floating-point values. */
1509 build_real_from_int_cst (type
, i
)
1514 int overflow
= TREE_OVERFLOW (i
);
1516 struct brfic_args args
;
1518 v
= make_node (REAL_CST
);
1519 TREE_TYPE (v
) = type
;
1521 /* Setup input for build_real_from_int_cst_1() */
1525 if (do_float_handler (build_real_from_int_cst_1
, (PTR
) &args
))
1526 /* Receive output from build_real_from_int_cst_1() */
1530 /* We got an exception from build_real_from_int_cst_1() */
1535 /* Check for valid float value for this type on this target machine. */
1537 #ifdef CHECK_FLOAT_VALUE
1538 CHECK_FLOAT_VALUE (TYPE_MODE (type
), d
, overflow
);
1541 TREE_REAL_CST (v
) = d
;
1542 TREE_OVERFLOW (v
) = TREE_CONSTANT_OVERFLOW (v
) = overflow
;
1546 #endif /* not REAL_IS_NOT_DOUBLE, or REAL_ARITHMETIC */
1548 /* Return a newly constructed STRING_CST node whose value is
1549 the LEN characters at STR.
1550 The TREE_TYPE is not initialized. */
1553 build_string (len
, str
)
1557 /* Put the string in saveable_obstack since it will be placed in the RTL
1558 for an "asm" statement and will also be kept around a while if
1559 deferring constant output in varasm.c. */
1561 register tree s
= make_node (STRING_CST
);
1563 TREE_STRING_LENGTH (s
) = len
;
1565 TREE_STRING_POINTER (s
) = ggc_alloc_string (str
, len
);
1567 TREE_STRING_POINTER (s
) = obstack_copy0 (saveable_obstack
, str
, len
);
1572 /* Return a newly constructed COMPLEX_CST node whose value is
1573 specified by the real and imaginary parts REAL and IMAG.
1574 Both REAL and IMAG should be constant nodes. TYPE, if specified,
1575 will be the type of the COMPLEX_CST; otherwise a new type will be made. */
1578 build_complex (type
, real
, imag
)
1582 register tree t
= make_node (COMPLEX_CST
);
1584 TREE_REALPART (t
) = real
;
1585 TREE_IMAGPART (t
) = imag
;
1586 TREE_TYPE (t
) = type
? type
: build_complex_type (TREE_TYPE (real
));
1587 TREE_OVERFLOW (t
) = TREE_OVERFLOW (real
) | TREE_OVERFLOW (imag
);
1588 TREE_CONSTANT_OVERFLOW (t
)
1589 = TREE_CONSTANT_OVERFLOW (real
) | TREE_CONSTANT_OVERFLOW (imag
);
1593 /* Build a newly constructed TREE_VEC node of length LEN. */
1600 register int length
= (len
-1) * sizeof (tree
) + sizeof (struct tree_vec
);
1601 register struct obstack
*obstack
= current_obstack
;
1603 #ifdef GATHER_STATISTICS
1604 tree_node_counts
[(int)vec_kind
]++;
1605 tree_node_sizes
[(int)vec_kind
] += length
;
1609 t
= ggc_alloc_tree (length
);
1612 t
= (tree
) obstack_alloc (obstack
, length
);
1613 bzero ((PTR
) t
, length
);
1616 TREE_SET_CODE (t
, TREE_VEC
);
1617 TREE_VEC_LENGTH (t
) = len
;
1618 TREE_SET_PERMANENT (t
);
1623 /* Return 1 if EXPR is the integer constant zero or a complex constant
1627 integer_zerop (expr
)
1632 return ((TREE_CODE (expr
) == INTEGER_CST
1633 && ! TREE_CONSTANT_OVERFLOW (expr
)
1634 && TREE_INT_CST_LOW (expr
) == 0
1635 && TREE_INT_CST_HIGH (expr
) == 0)
1636 || (TREE_CODE (expr
) == COMPLEX_CST
1637 && integer_zerop (TREE_REALPART (expr
))
1638 && integer_zerop (TREE_IMAGPART (expr
))));
1641 /* Return 1 if EXPR is the integer constant one or the corresponding
1642 complex constant. */
1650 return ((TREE_CODE (expr
) == INTEGER_CST
1651 && ! TREE_CONSTANT_OVERFLOW (expr
)
1652 && TREE_INT_CST_LOW (expr
) == 1
1653 && TREE_INT_CST_HIGH (expr
) == 0)
1654 || (TREE_CODE (expr
) == COMPLEX_CST
1655 && integer_onep (TREE_REALPART (expr
))
1656 && integer_zerop (TREE_IMAGPART (expr
))));
1659 /* Return 1 if EXPR is an integer containing all 1's in as much precision as
1660 it contains. Likewise for the corresponding complex constant. */
1663 integer_all_onesp (expr
)
1671 if (TREE_CODE (expr
) == COMPLEX_CST
1672 && integer_all_onesp (TREE_REALPART (expr
))
1673 && integer_zerop (TREE_IMAGPART (expr
)))
1676 else if (TREE_CODE (expr
) != INTEGER_CST
1677 || TREE_CONSTANT_OVERFLOW (expr
))
1680 uns
= TREE_UNSIGNED (TREE_TYPE (expr
));
1682 return (TREE_INT_CST_LOW (expr
) == ~ (unsigned HOST_WIDE_INT
) 0
1683 && TREE_INT_CST_HIGH (expr
) == -1);
1685 /* Note that using TYPE_PRECISION here is wrong. We care about the
1686 actual bits, not the (arbitrary) range of the type. */
1687 prec
= GET_MODE_BITSIZE (TYPE_MODE (TREE_TYPE (expr
)));
1688 if (prec
>= HOST_BITS_PER_WIDE_INT
)
1690 HOST_WIDE_INT high_value
;
1693 shift_amount
= prec
- HOST_BITS_PER_WIDE_INT
;
1695 if (shift_amount
> HOST_BITS_PER_WIDE_INT
)
1696 /* Can not handle precisions greater than twice the host int size. */
1698 else if (shift_amount
== HOST_BITS_PER_WIDE_INT
)
1699 /* Shifting by the host word size is undefined according to the ANSI
1700 standard, so we must handle this as a special case. */
1703 high_value
= ((HOST_WIDE_INT
) 1 << shift_amount
) - 1;
1705 return (TREE_INT_CST_LOW (expr
) == ~ (unsigned HOST_WIDE_INT
) 0
1706 && TREE_INT_CST_HIGH (expr
) == high_value
);
1709 return TREE_INT_CST_LOW (expr
) == ((unsigned HOST_WIDE_INT
) 1 << prec
) - 1;
1712 /* Return 1 if EXPR is an integer constant that is a power of 2 (i.e., has only
1716 integer_pow2p (expr
)
1720 HOST_WIDE_INT high
, low
;
1724 if (TREE_CODE (expr
) == COMPLEX_CST
1725 && integer_pow2p (TREE_REALPART (expr
))
1726 && integer_zerop (TREE_IMAGPART (expr
)))
1729 if (TREE_CODE (expr
) != INTEGER_CST
|| TREE_CONSTANT_OVERFLOW (expr
))
1732 prec
= (POINTER_TYPE_P (TREE_TYPE (expr
))
1733 ? POINTER_SIZE
: TYPE_PRECISION (TREE_TYPE (expr
)));
1734 high
= TREE_INT_CST_HIGH (expr
);
1735 low
= TREE_INT_CST_LOW (expr
);
1737 /* First clear all bits that are beyond the type's precision in case
1738 we've been sign extended. */
1740 if (prec
== 2 * HOST_BITS_PER_WIDE_INT
)
1742 else if (prec
> HOST_BITS_PER_WIDE_INT
)
1743 high
&= ~((HOST_WIDE_INT
) (-1) << (prec
- HOST_BITS_PER_WIDE_INT
));
1747 if (prec
< HOST_BITS_PER_WIDE_INT
)
1748 low
&= ~((HOST_WIDE_INT
) (-1) << prec
);
1751 if (high
== 0 && low
== 0)
1754 return ((high
== 0 && (low
& (low
- 1)) == 0)
1755 || (low
== 0 && (high
& (high
- 1)) == 0));
1758 /* Return the power of two represented by a tree node known to be a
1766 HOST_WIDE_INT high
, low
;
1770 if (TREE_CODE (expr
) == COMPLEX_CST
)
1771 return tree_log2 (TREE_REALPART (expr
));
1773 prec
= (POINTER_TYPE_P (TREE_TYPE (expr
))
1774 ? POINTER_SIZE
: TYPE_PRECISION (TREE_TYPE (expr
)));
1776 high
= TREE_INT_CST_HIGH (expr
);
1777 low
= TREE_INT_CST_LOW (expr
);
1779 /* First clear all bits that are beyond the type's precision in case
1780 we've been sign extended. */
1782 if (prec
== 2 * HOST_BITS_PER_WIDE_INT
)
1784 else if (prec
> HOST_BITS_PER_WIDE_INT
)
1785 high
&= ~((HOST_WIDE_INT
) (-1) << (prec
- HOST_BITS_PER_WIDE_INT
));
1789 if (prec
< HOST_BITS_PER_WIDE_INT
)
1790 low
&= ~((HOST_WIDE_INT
) (-1) << prec
);
1793 return (high
!= 0 ? HOST_BITS_PER_WIDE_INT
+ exact_log2 (high
)
1794 : exact_log2 (low
));
1797 /* Similar, but return the largest integer Y such that 2 ** Y is less
1798 than or equal to EXPR. */
1801 tree_floor_log2 (expr
)
1805 HOST_WIDE_INT high
, low
;
1809 if (TREE_CODE (expr
) == COMPLEX_CST
)
1810 return tree_log2 (TREE_REALPART (expr
));
1812 prec
= (POINTER_TYPE_P (TREE_TYPE (expr
))
1813 ? POINTER_SIZE
: TYPE_PRECISION (TREE_TYPE (expr
)));
1815 high
= TREE_INT_CST_HIGH (expr
);
1816 low
= TREE_INT_CST_LOW (expr
);
1818 /* First clear all bits that are beyond the type's precision in case
1819 we've been sign extended. Ignore if type's precision hasn't been set
1820 since what we are doing is setting it. */
1822 if (prec
== 2 * HOST_BITS_PER_WIDE_INT
|| prec
== 0)
1824 else if (prec
> HOST_BITS_PER_WIDE_INT
)
1825 high
&= ~((HOST_WIDE_INT
) (-1) << (prec
- HOST_BITS_PER_WIDE_INT
));
1829 if (prec
< HOST_BITS_PER_WIDE_INT
)
1830 low
&= ~((HOST_WIDE_INT
) (-1) << prec
);
1833 return (high
!= 0 ? HOST_BITS_PER_WIDE_INT
+ floor_log2 (high
)
1834 : floor_log2 (low
));
1837 /* Return 1 if EXPR is the real constant zero. */
1845 return ((TREE_CODE (expr
) == REAL_CST
1846 && ! TREE_CONSTANT_OVERFLOW (expr
)
1847 && REAL_VALUES_EQUAL (TREE_REAL_CST (expr
), dconst0
))
1848 || (TREE_CODE (expr
) == COMPLEX_CST
1849 && real_zerop (TREE_REALPART (expr
))
1850 && real_zerop (TREE_IMAGPART (expr
))));
1853 /* Return 1 if EXPR is the real constant one in real or complex form. */
1861 return ((TREE_CODE (expr
) == REAL_CST
1862 && ! TREE_CONSTANT_OVERFLOW (expr
)
1863 && REAL_VALUES_EQUAL (TREE_REAL_CST (expr
), dconst1
))
1864 || (TREE_CODE (expr
) == COMPLEX_CST
1865 && real_onep (TREE_REALPART (expr
))
1866 && real_zerop (TREE_IMAGPART (expr
))));
1869 /* Return 1 if EXPR is the real constant two. */
1877 return ((TREE_CODE (expr
) == REAL_CST
1878 && ! TREE_CONSTANT_OVERFLOW (expr
)
1879 && REAL_VALUES_EQUAL (TREE_REAL_CST (expr
), dconst2
))
1880 || (TREE_CODE (expr
) == COMPLEX_CST
1881 && real_twop (TREE_REALPART (expr
))
1882 && real_zerop (TREE_IMAGPART (expr
))));
1885 /* Nonzero if EXP is a constant or a cast of a constant. */
1888 really_constant_p (exp
)
1891 /* This is not quite the same as STRIP_NOPS. It does more. */
1892 while (TREE_CODE (exp
) == NOP_EXPR
1893 || TREE_CODE (exp
) == CONVERT_EXPR
1894 || TREE_CODE (exp
) == NON_LVALUE_EXPR
)
1895 exp
= TREE_OPERAND (exp
, 0);
1896 return TREE_CONSTANT (exp
);
1899 /* Return first list element whose TREE_VALUE is ELEM.
1900 Return 0 if ELEM is not in LIST. */
1903 value_member (elem
, list
)
1908 if (elem
== TREE_VALUE (list
))
1910 list
= TREE_CHAIN (list
);
1915 /* Return first list element whose TREE_PURPOSE is ELEM.
1916 Return 0 if ELEM is not in LIST. */
1919 purpose_member (elem
, list
)
1924 if (elem
== TREE_PURPOSE (list
))
1926 list
= TREE_CHAIN (list
);
1931 /* Return first list element whose BINFO_TYPE is ELEM.
1932 Return 0 if ELEM is not in LIST. */
1935 binfo_member (elem
, list
)
1940 if (elem
== BINFO_TYPE (list
))
1942 list
= TREE_CHAIN (list
);
1947 /* Return nonzero if ELEM is part of the chain CHAIN. */
1950 chain_member (elem
, chain
)
1957 chain
= TREE_CHAIN (chain
);
1963 /* Return nonzero if ELEM is equal to TREE_VALUE (CHAIN) for any piece of
1964 chain CHAIN. This and the next function are currently unused, but
1965 are retained for completeness. */
1968 chain_member_value (elem
, chain
)
1973 if (elem
== TREE_VALUE (chain
))
1975 chain
= TREE_CHAIN (chain
);
1981 /* Return nonzero if ELEM is equal to TREE_PURPOSE (CHAIN)
1982 for any piece of chain CHAIN. */
1985 chain_member_purpose (elem
, chain
)
1990 if (elem
== TREE_PURPOSE (chain
))
1992 chain
= TREE_CHAIN (chain
);
1998 /* Return the length of a chain of nodes chained through TREE_CHAIN.
1999 We expect a null pointer to mark the end of the chain.
2000 This is the Lisp primitive `length'. */
2007 register int len
= 0;
2009 for (tail
= t
; tail
; tail
= TREE_CHAIN (tail
))
2015 /* Returns the number of FIELD_DECLs in TYPE. */
2018 fields_length (type
)
2021 tree t
= TYPE_FIELDS (type
);
2024 for (; t
; t
= TREE_CHAIN (t
))
2025 if (TREE_CODE (t
) == FIELD_DECL
)
2031 /* Concatenate two chains of nodes (chained through TREE_CHAIN)
2032 by modifying the last node in chain 1 to point to chain 2.
2033 This is the Lisp primitive `nconc'. */
2043 #ifdef ENABLE_TREE_CHECKING
2047 for (t1
= op1
; TREE_CHAIN (t1
); t1
= TREE_CHAIN (t1
))
2049 TREE_CHAIN (t1
) = op2
;
2050 #ifdef ENABLE_TREE_CHECKING
2051 for (t2
= op2
; t2
; t2
= TREE_CHAIN (t2
))
2053 abort (); /* Circularity created. */
2060 /* Return the last node in a chain of nodes (chained through TREE_CHAIN). */
2064 register tree chain
;
2068 while ((next
= TREE_CHAIN (chain
)))
2073 /* Reverse the order of elements in the chain T,
2074 and return the new head of the chain (old last element). */
2080 register tree prev
= 0, decl
, next
;
2081 for (decl
= t
; decl
; decl
= next
)
2083 next
= TREE_CHAIN (decl
);
2084 TREE_CHAIN (decl
) = prev
;
2090 /* Given a chain CHAIN of tree nodes,
2091 construct and return a list of those nodes. */
2097 tree result
= NULL_TREE
;
2098 tree in_tail
= chain
;
2099 tree out_tail
= NULL_TREE
;
2103 tree next
= tree_cons (NULL_TREE
, in_tail
, NULL_TREE
);
2105 TREE_CHAIN (out_tail
) = next
;
2109 in_tail
= TREE_CHAIN (in_tail
);
2115 /* Return a newly created TREE_LIST node whose
2116 purpose and value fields are PARM and VALUE. */
2119 build_tree_list (parm
, value
)
2122 register tree t
= make_node (TREE_LIST
);
2123 TREE_PURPOSE (t
) = parm
;
2124 TREE_VALUE (t
) = value
;
2128 /* Similar, but build on the temp_decl_obstack. */
2131 build_decl_list (parm
, value
)
2135 register struct obstack
*ambient_obstack
= current_obstack
;
2137 current_obstack
= &temp_decl_obstack
;
2138 node
= build_tree_list (parm
, value
);
2139 current_obstack
= ambient_obstack
;
2143 /* Similar, but build on the expression_obstack. */
2146 build_expr_list (parm
, value
)
2150 register struct obstack
*ambient_obstack
= current_obstack
;
2152 current_obstack
= expression_obstack
;
2153 node
= build_tree_list (parm
, value
);
2154 current_obstack
= ambient_obstack
;
2158 /* Return a newly created TREE_LIST node whose
2159 purpose and value fields are PARM and VALUE
2160 and whose TREE_CHAIN is CHAIN. */
2163 tree_cons (purpose
, value
, chain
)
2164 tree purpose
, value
, chain
;
2169 node
= ggc_alloc_tree (sizeof (struct tree_list
));
2172 node
= (tree
) obstack_alloc (current_obstack
, sizeof (struct tree_list
));
2173 memset (node
, 0, sizeof (struct tree_common
));
2176 #ifdef GATHER_STATISTICS
2177 tree_node_counts
[(int) x_kind
]++;
2178 tree_node_sizes
[(int) x_kind
] += sizeof (struct tree_list
);
2181 TREE_SET_CODE (node
, TREE_LIST
);
2182 TREE_SET_PERMANENT (node
);
2184 TREE_CHAIN (node
) = chain
;
2185 TREE_PURPOSE (node
) = purpose
;
2186 TREE_VALUE (node
) = value
;
2190 /* Similar, but build on the temp_decl_obstack. */
2193 decl_tree_cons (purpose
, value
, chain
)
2194 tree purpose
, value
, chain
;
2197 register struct obstack
*ambient_obstack
= current_obstack
;
2199 current_obstack
= &temp_decl_obstack
;
2200 node
= tree_cons (purpose
, value
, chain
);
2201 current_obstack
= ambient_obstack
;
2205 /* Similar, but build on the expression_obstack. */
2208 expr_tree_cons (purpose
, value
, chain
)
2209 tree purpose
, value
, chain
;
2212 register struct obstack
*ambient_obstack
= current_obstack
;
2214 current_obstack
= expression_obstack
;
2215 node
= tree_cons (purpose
, value
, chain
);
2216 current_obstack
= ambient_obstack
;
2220 /* Same as `tree_cons' but make a permanent object. */
2223 perm_tree_cons (purpose
, value
, chain
)
2224 tree purpose
, value
, chain
;
2227 register struct obstack
*ambient_obstack
= current_obstack
;
2229 current_obstack
= &permanent_obstack
;
2230 node
= tree_cons (purpose
, value
, chain
);
2231 current_obstack
= ambient_obstack
;
2235 /* Same as `tree_cons', but make this node temporary, regardless. */
2238 temp_tree_cons (purpose
, value
, chain
)
2239 tree purpose
, value
, chain
;
2242 register struct obstack
*ambient_obstack
= current_obstack
;
2244 current_obstack
= &temporary_obstack
;
2245 node
= tree_cons (purpose
, value
, chain
);
2246 current_obstack
= ambient_obstack
;
2250 /* Same as `tree_cons', but save this node if the function's RTL is saved. */
2253 saveable_tree_cons (purpose
, value
, chain
)
2254 tree purpose
, value
, chain
;
2257 register struct obstack
*ambient_obstack
= current_obstack
;
2259 current_obstack
= saveable_obstack
;
2260 node
= tree_cons (purpose
, value
, chain
);
2261 current_obstack
= ambient_obstack
;
2265 /* Return the size nominally occupied by an object of type TYPE
2266 when it resides in memory. The value is measured in units of bytes,
2267 and its data type is that normally used for type sizes
2268 (which is the first type created by make_signed_type or
2269 make_unsigned_type). */
2272 size_in_bytes (type
)
2277 if (type
== error_mark_node
)
2278 return integer_zero_node
;
2280 type
= TYPE_MAIN_VARIANT (type
);
2281 t
= TYPE_SIZE_UNIT (type
);
2285 incomplete_type_error (NULL_TREE
, type
);
2286 return size_zero_node
;
2289 if (TREE_CODE (t
) == INTEGER_CST
)
2290 force_fit_type (t
, 0);
2295 /* Return the size of TYPE (in bytes) as a wide integer
2296 or return -1 if the size can vary or is larger than an integer. */
2299 int_size_in_bytes (type
)
2304 if (type
== error_mark_node
)
2307 type
= TYPE_MAIN_VARIANT (type
);
2308 t
= TYPE_SIZE_UNIT (type
);
2310 || TREE_CODE (t
) != INTEGER_CST
2311 || TREE_OVERFLOW (t
)
2312 || TREE_INT_CST_HIGH (t
) != 0
2313 /* If the result would appear negative, it's too big to represent. */
2314 || (HOST_WIDE_INT
) TREE_INT_CST_LOW (t
) < 0)
2317 return TREE_INT_CST_LOW (t
);
2320 /* Return the bit position of FIELD, in bits from the start of the record.
2321 This is a tree of type bitsizetype. */
2324 bit_position (field
)
2328 return bit_from_pos (DECL_FIELD_OFFSET (field
),
2329 DECL_FIELD_BIT_OFFSET (field
));
2332 /* Likewise, but return as an integer. Abort if it cannot be represented
2333 in that way (since it could be a signed value, we don't have the option
2334 of returning -1 like int_size_in_byte can. */
2337 int_bit_position (field
)
2340 return tree_low_cst (bit_position (field
), 0);
2343 /* Return the byte position of FIELD, in bytes from the start of the record.
2344 This is a tree of type sizetype. */
2347 byte_position (field
)
2350 return byte_from_pos (DECL_FIELD_OFFSET (field
),
2351 DECL_FIELD_BIT_OFFSET (field
));
2354 /* Likewise, but return as an integer. Abort if it cannot be represented
2355 in that way (since it could be a signed value, we don't have the option
2356 of returning -1 like int_size_in_byte can. */
2359 int_byte_position (field
)
2362 return tree_low_cst (byte_position (field
), 0);
2365 /* Return the strictest alignment, in bits, that T is known to have. */
2371 unsigned int align0
, align1
;
2373 switch (TREE_CODE (t
))
2375 case NOP_EXPR
: case CONVERT_EXPR
: case NON_LVALUE_EXPR
:
2376 /* If we have conversions, we know that the alignment of the
2377 object must meet each of the alignments of the types. */
2378 align0
= expr_align (TREE_OPERAND (t
, 0));
2379 align1
= TYPE_ALIGN (TREE_TYPE (t
));
2380 return MAX (align0
, align1
);
2382 case SAVE_EXPR
: case COMPOUND_EXPR
: case MODIFY_EXPR
:
2383 case INIT_EXPR
: case TARGET_EXPR
: case WITH_CLEANUP_EXPR
:
2384 case WITH_RECORD_EXPR
: case CLEANUP_POINT_EXPR
: case UNSAVE_EXPR
:
2385 /* These don't change the alignment of an object. */
2386 return expr_align (TREE_OPERAND (t
, 0));
2389 /* The best we can do is say that the alignment is the least aligned
2391 align0
= expr_align (TREE_OPERAND (t
, 1));
2392 align1
= expr_align (TREE_OPERAND (t
, 2));
2393 return MIN (align0
, align1
);
2395 case LABEL_DECL
: case CONST_DECL
:
2396 case VAR_DECL
: case PARM_DECL
: case RESULT_DECL
:
2397 if (DECL_ALIGN (t
) != 0)
2398 return DECL_ALIGN (t
);
2402 return FUNCTION_BOUNDARY
;
2408 /* Otherwise take the alignment from that of the type. */
2409 return TYPE_ALIGN (TREE_TYPE (t
));
2412 /* Return, as a tree node, the number of elements for TYPE (which is an
2413 ARRAY_TYPE) minus one. This counts only elements of the top array. */
2416 array_type_nelts (type
)
2419 tree index_type
, min
, max
;
2421 /* If they did it with unspecified bounds, then we should have already
2422 given an error about it before we got here. */
2423 if (! TYPE_DOMAIN (type
))
2424 return error_mark_node
;
2426 index_type
= TYPE_DOMAIN (type
);
2427 min
= TYPE_MIN_VALUE (index_type
);
2428 max
= TYPE_MAX_VALUE (index_type
);
2430 return (integer_zerop (min
)
2432 : fold (build (MINUS_EXPR
, TREE_TYPE (max
), max
, min
)));
2435 /* Return nonzero if arg is static -- a reference to an object in
2436 static storage. This is not the same as the C meaning of `static'. */
2442 switch (TREE_CODE (arg
))
2445 /* Nested functions aren't static, since taking their address
2446 involves a trampoline. */
2447 return (decl_function_context (arg
) == 0 || DECL_NO_STATIC_CHAIN (arg
))
2448 && ! DECL_NON_ADDR_CONST_P (arg
);
2451 return (TREE_STATIC (arg
) || DECL_EXTERNAL (arg
))
2452 && ! DECL_NON_ADDR_CONST_P (arg
);
2455 return TREE_STATIC (arg
);
2461 /* If we are referencing a bitfield, we can't evaluate an
2462 ADDR_EXPR at compile time and so it isn't a constant. */
2464 return (! DECL_BIT_FIELD (TREE_OPERAND (arg
, 1))
2465 && staticp (TREE_OPERAND (arg
, 0)));
2471 /* This case is technically correct, but results in setting
2472 TREE_CONSTANT on ADDR_EXPRs that cannot be evaluated at
2475 return TREE_CONSTANT (TREE_OPERAND (arg
, 0));
2479 if (TREE_CODE (TYPE_SIZE (TREE_TYPE (arg
))) == INTEGER_CST
2480 && TREE_CODE (TREE_OPERAND (arg
, 1)) == INTEGER_CST
)
2481 return staticp (TREE_OPERAND (arg
, 0));
2488 /* Wrap a SAVE_EXPR around EXPR, if appropriate.
2489 Do this to any expression which may be used in more than one place,
2490 but must be evaluated only once.
2492 Normally, expand_expr would reevaluate the expression each time.
2493 Calling save_expr produces something that is evaluated and recorded
2494 the first time expand_expr is called on it. Subsequent calls to
2495 expand_expr just reuse the recorded value.
2497 The call to expand_expr that generates code that actually computes
2498 the value is the first call *at compile time*. Subsequent calls
2499 *at compile time* generate code to use the saved value.
2500 This produces correct result provided that *at run time* control
2501 always flows through the insns made by the first expand_expr
2502 before reaching the other places where the save_expr was evaluated.
2503 You, the caller of save_expr, must make sure this is so.
2505 Constants, and certain read-only nodes, are returned with no
2506 SAVE_EXPR because that is safe. Expressions containing placeholders
2507 are not touched; see tree.def for an explanation of what these
2514 register tree t
= fold (expr
);
2516 /* We don't care about whether this can be used as an lvalue in this
2518 while (TREE_CODE (t
) == NON_LVALUE_EXPR
)
2519 t
= TREE_OPERAND (t
, 0);
2521 /* If the tree evaluates to a constant, then we don't want to hide that
2522 fact (i.e. this allows further folding, and direct checks for constants).
2523 However, a read-only object that has side effects cannot be bypassed.
2524 Since it is no problem to reevaluate literals, we just return the
2527 if (TREE_CONSTANT (t
) || (TREE_READONLY (t
) && ! TREE_SIDE_EFFECTS (t
))
2528 || TREE_CODE (t
) == SAVE_EXPR
|| TREE_CODE (t
) == ERROR_MARK
)
2531 /* If T contains a PLACEHOLDER_EXPR, we must evaluate it each time, since
2532 it means that the size or offset of some field of an object depends on
2533 the value within another field.
2535 Note that it must not be the case that T contains both a PLACEHOLDER_EXPR
2536 and some variable since it would then need to be both evaluated once and
2537 evaluated more than once. Front-ends must assure this case cannot
2538 happen by surrounding any such subexpressions in their own SAVE_EXPR
2539 and forcing evaluation at the proper time. */
2540 if (contains_placeholder_p (t
))
2543 t
= build (SAVE_EXPR
, TREE_TYPE (expr
), t
, current_function_decl
, NULL_TREE
);
2545 /* This expression might be placed ahead of a jump to ensure that the
2546 value was computed on both sides of the jump. So make sure it isn't
2547 eliminated as dead. */
2548 TREE_SIDE_EFFECTS (t
) = 1;
2552 /* Arrange for an expression to be expanded multiple independent
2553 times. This is useful for cleanup actions, as the backend can
2554 expand them multiple times in different places. */
2562 /* If this is already protected, no sense in protecting it again. */
2563 if (TREE_CODE (expr
) == UNSAVE_EXPR
)
2566 t
= build1 (UNSAVE_EXPR
, TREE_TYPE (expr
), expr
);
2567 TREE_SIDE_EFFECTS (t
) = TREE_SIDE_EFFECTS (expr
);
2571 /* Returns the index of the first non-tree operand for CODE, or the number
2572 of operands if all are trees. */
2576 enum tree_code code
;
2582 case GOTO_SUBROUTINE_EXPR
:
2587 case WITH_CLEANUP_EXPR
:
2588 /* Should be defined to be 2. */
2590 case METHOD_CALL_EXPR
:
2593 return tree_code_length
[(int) code
];
2597 /* Perform any modifications to EXPR required when it is unsaved. Does
2598 not recurse into EXPR's subtrees. */
2601 unsave_expr_1 (expr
)
2604 switch (TREE_CODE (expr
))
2607 if (! SAVE_EXPR_PERSISTENT_P (expr
))
2608 SAVE_EXPR_RTL (expr
) = 0;
2612 /* Don't mess with a TARGET_EXPR that hasn't been expanded.
2613 It's OK for this to happen if it was part of a subtree that
2614 isn't immediately expanded, such as operand 2 of another
2616 if (TREE_OPERAND (expr
, 1))
2619 TREE_OPERAND (expr
, 1) = TREE_OPERAND (expr
, 3);
2620 TREE_OPERAND (expr
, 3) = NULL_TREE
;
2624 /* I don't yet know how to emit a sequence multiple times. */
2625 if (RTL_EXPR_SEQUENCE (expr
) != 0)
2630 CALL_EXPR_RTL (expr
) = 0;
2634 if (lang_unsave_expr_now
!= 0)
2635 (*lang_unsave_expr_now
) (expr
);
2640 /* Helper function for unsave_expr_now. */
2643 unsave_expr_now_r (expr
)
2646 enum tree_code code
;
2648 /* There's nothing to do for NULL_TREE. */
2652 unsave_expr_1 (expr
);
2654 code
= TREE_CODE (expr
);
2655 switch (TREE_CODE_CLASS (code
))
2657 case 'c': /* a constant */
2658 case 't': /* a type node */
2659 case 'd': /* A decl node */
2660 case 'b': /* A block node */
2663 case 'x': /* miscellaneous: e.g., identifier, TREE_LIST or ERROR_MARK. */
2664 if (code
== TREE_LIST
)
2666 unsave_expr_now_r (TREE_VALUE (expr
));
2667 unsave_expr_now_r (TREE_CHAIN (expr
));
2671 case 'e': /* an expression */
2672 case 'r': /* a reference */
2673 case 's': /* an expression with side effects */
2674 case '<': /* a comparison expression */
2675 case '2': /* a binary arithmetic expression */
2676 case '1': /* a unary arithmetic expression */
2680 for (i
= first_rtl_op (code
) - 1; i
>= 0; i
--)
2681 unsave_expr_now_r (TREE_OPERAND (expr
, i
));
2690 /* Modify a tree in place so that all the evaluate only once things
2691 are cleared out. Return the EXPR given. */
2694 unsave_expr_now (expr
)
2697 if (lang_unsave
!= 0)
2698 (*lang_unsave
) (&expr
);
2700 unsave_expr_now_r (expr
);
2705 /* Return 0 if it is safe to evaluate EXPR multiple times,
2706 return 1 if it is safe if EXPR is unsaved afterward, or
2707 return 2 if it is completely unsafe.
2709 This assumes that CALL_EXPRs and TARGET_EXPRs are never replicated in
2710 an expression tree, so that it safe to unsave them and the surrounding
2711 context will be correct.
2713 SAVE_EXPRs basically *only* appear replicated in an expression tree,
2714 occasionally across the whole of a function. It is therefore only
2715 safe to unsave a SAVE_EXPR if you know that all occurrences appear
2716 below the UNSAVE_EXPR.
2718 RTL_EXPRs consume their rtl during evaluation. It is therefore
2719 never possible to unsave them. */
2722 unsafe_for_reeval (expr
)
2726 enum tree_code code
;
2731 if (expr
== NULL_TREE
)
2734 code
= TREE_CODE (expr
);
2735 first_rtl
= first_rtl_op (code
);
2744 for (exp
= expr
; exp
!= 0; exp
= TREE_CHAIN (exp
))
2746 tmp
= unsafe_for_reeval (TREE_VALUE (exp
));
2747 unsafeness
= MAX (tmp
, unsafeness
);
2753 tmp
= unsafe_for_reeval (TREE_OPERAND (expr
, 1));
2754 return MAX (tmp
, 1);
2761 /* ??? Add a lang hook if it becomes necessary. */
2765 switch (TREE_CODE_CLASS (code
))
2767 case 'c': /* a constant */
2768 case 't': /* a type node */
2769 case 'x': /* something random, like an identifier or an ERROR_MARK. */
2770 case 'd': /* A decl node */
2771 case 'b': /* A block node */
2774 case 'e': /* an expression */
2775 case 'r': /* a reference */
2776 case 's': /* an expression with side effects */
2777 case '<': /* a comparison expression */
2778 case '2': /* a binary arithmetic expression */
2779 case '1': /* a unary arithmetic expression */
2780 for (i
= first_rtl
- 1; i
>= 0; i
--)
2782 tmp
= unsafe_for_reeval (TREE_OPERAND (expr
, i
));
2783 unsafeness
= MAX (tmp
, unsafeness
);
2793 /* Return 1 if EXP contains a PLACEHOLDER_EXPR; i.e., if it represents a size
2794 or offset that depends on a field within a record. */
2797 contains_placeholder_p (exp
)
2800 register enum tree_code code
= TREE_CODE (exp
);
2803 /* If we have a WITH_RECORD_EXPR, it "cancels" any PLACEHOLDER_EXPR
2804 in it since it is supplying a value for it. */
2805 if (code
== WITH_RECORD_EXPR
)
2807 else if (code
== PLACEHOLDER_EXPR
)
2810 switch (TREE_CODE_CLASS (code
))
2813 /* Don't look at any PLACEHOLDER_EXPRs that might be in index or bit
2814 position computations since they will be converted into a
2815 WITH_RECORD_EXPR involving the reference, which will assume
2816 here will be valid. */
2817 return contains_placeholder_p (TREE_OPERAND (exp
, 0));
2820 if (code
== TREE_LIST
)
2821 return (contains_placeholder_p (TREE_VALUE (exp
))
2822 || (TREE_CHAIN (exp
) != 0
2823 && contains_placeholder_p (TREE_CHAIN (exp
))));
2832 /* Ignoring the first operand isn't quite right, but works best. */
2833 return contains_placeholder_p (TREE_OPERAND (exp
, 1));
2840 return (contains_placeholder_p (TREE_OPERAND (exp
, 0))
2841 || contains_placeholder_p (TREE_OPERAND (exp
, 1))
2842 || contains_placeholder_p (TREE_OPERAND (exp
, 2)));
2845 /* If we already know this doesn't have a placeholder, don't
2847 if (SAVE_EXPR_NOPLACEHOLDER (exp
) || SAVE_EXPR_RTL (exp
) != 0)
2850 SAVE_EXPR_NOPLACEHOLDER (exp
) = 1;
2851 result
= contains_placeholder_p (TREE_OPERAND (exp
, 0));
2853 SAVE_EXPR_NOPLACEHOLDER (exp
) = 0;
2858 return (TREE_OPERAND (exp
, 1) != 0
2859 && contains_placeholder_p (TREE_OPERAND (exp
, 1)));
2865 switch (tree_code_length
[(int) code
])
2868 return contains_placeholder_p (TREE_OPERAND (exp
, 0));
2870 return (contains_placeholder_p (TREE_OPERAND (exp
, 0))
2871 || contains_placeholder_p (TREE_OPERAND (exp
, 1)));
2882 /* Return 1 if EXP contains any expressions that produce cleanups for an
2883 outer scope to deal with. Used by fold. */
2891 if (! TREE_SIDE_EFFECTS (exp
))
2894 switch (TREE_CODE (exp
))
2897 case GOTO_SUBROUTINE_EXPR
:
2898 case WITH_CLEANUP_EXPR
:
2901 case CLEANUP_POINT_EXPR
:
2905 for (exp
= TREE_OPERAND (exp
, 1); exp
; exp
= TREE_CHAIN (exp
))
2907 cmp
= has_cleanups (TREE_VALUE (exp
));
2917 /* This general rule works for most tree codes. All exceptions should be
2918 handled above. If this is a language-specific tree code, we can't
2919 trust what might be in the operand, so say we don't know
2921 if ((int) TREE_CODE (exp
) >= (int) LAST_AND_UNUSED_TREE_CODE
)
2924 nops
= first_rtl_op (TREE_CODE (exp
));
2925 for (i
= 0; i
< nops
; i
++)
2926 if (TREE_OPERAND (exp
, i
) != 0)
2928 int type
= TREE_CODE_CLASS (TREE_CODE (TREE_OPERAND (exp
, i
)));
2929 if (type
== 'e' || type
== '<' || type
== '1' || type
== '2'
2930 || type
== 'r' || type
== 's')
2932 cmp
= has_cleanups (TREE_OPERAND (exp
, i
));
2941 /* Given a tree EXP, a FIELD_DECL F, and a replacement value R,
2942 return a tree with all occurrences of references to F in a
2943 PLACEHOLDER_EXPR replaced by R. Note that we assume here that EXP
2944 contains only arithmetic expressions or a CALL_EXPR with a
2945 PLACEHOLDER_EXPR occurring only in its arglist. */
2948 substitute_in_expr (exp
, f
, r
)
2953 enum tree_code code
= TREE_CODE (exp
);
2958 switch (TREE_CODE_CLASS (code
))
2965 if (code
== PLACEHOLDER_EXPR
)
2967 else if (code
== TREE_LIST
)
2969 op0
= (TREE_CHAIN (exp
) == 0
2970 ? 0 : substitute_in_expr (TREE_CHAIN (exp
), f
, r
));
2971 op1
= substitute_in_expr (TREE_VALUE (exp
), f
, r
);
2972 if (op0
== TREE_CHAIN (exp
) && op1
== TREE_VALUE (exp
))
2975 return tree_cons (TREE_PURPOSE (exp
), op1
, op0
);
2984 switch (tree_code_length
[(int) code
])
2987 op0
= substitute_in_expr (TREE_OPERAND (exp
, 0), f
, r
);
2988 if (op0
== TREE_OPERAND (exp
, 0))
2991 new = fold (build1 (code
, TREE_TYPE (exp
), op0
));
2995 /* An RTL_EXPR cannot contain a PLACEHOLDER_EXPR; a CONSTRUCTOR
2996 could, but we don't support it. */
2997 if (code
== RTL_EXPR
)
2999 else if (code
== CONSTRUCTOR
)
3002 op0
= substitute_in_expr (TREE_OPERAND (exp
, 0), f
, r
);
3003 op1
= substitute_in_expr (TREE_OPERAND (exp
, 1), f
, r
);
3004 if (op0
== TREE_OPERAND (exp
, 0) && op1
== TREE_OPERAND (exp
, 1))
3007 new = fold (build (code
, TREE_TYPE (exp
), op0
, op1
));
3011 /* It cannot be that anything inside a SAVE_EXPR contains a
3012 PLACEHOLDER_EXPR. */
3013 if (code
== SAVE_EXPR
)
3016 else if (code
== CALL_EXPR
)
3018 op1
= substitute_in_expr (TREE_OPERAND (exp
, 1), f
, r
);
3019 if (op1
== TREE_OPERAND (exp
, 1))
3022 return build (code
, TREE_TYPE (exp
),
3023 TREE_OPERAND (exp
, 0), op1
, NULL_TREE
);
3026 else if (code
!= COND_EXPR
)
3029 op0
= substitute_in_expr (TREE_OPERAND (exp
, 0), f
, r
);
3030 op1
= substitute_in_expr (TREE_OPERAND (exp
, 1), f
, r
);
3031 op2
= substitute_in_expr (TREE_OPERAND (exp
, 2), f
, r
);
3032 if (op0
== TREE_OPERAND (exp
, 0) && op1
== TREE_OPERAND (exp
, 1)
3033 && op2
== TREE_OPERAND (exp
, 2))
3036 new = fold (build (code
, TREE_TYPE (exp
), op0
, op1
, op2
));
3049 /* If this expression is getting a value from a PLACEHOLDER_EXPR
3050 and it is the right field, replace it with R. */
3051 for (inner
= TREE_OPERAND (exp
, 0);
3052 TREE_CODE_CLASS (TREE_CODE (inner
)) == 'r';
3053 inner
= TREE_OPERAND (inner
, 0))
3055 if (TREE_CODE (inner
) == PLACEHOLDER_EXPR
3056 && TREE_OPERAND (exp
, 1) == f
)
3059 /* If this expression hasn't been completed let, leave it
3061 if (TREE_CODE (inner
) == PLACEHOLDER_EXPR
3062 && TREE_TYPE (inner
) == 0)
3065 op0
= substitute_in_expr (TREE_OPERAND (exp
, 0), f
, r
);
3066 if (op0
== TREE_OPERAND (exp
, 0))
3069 new = fold (build (code
, TREE_TYPE (exp
), op0
,
3070 TREE_OPERAND (exp
, 1)));
3074 op0
= substitute_in_expr (TREE_OPERAND (exp
, 0), f
, r
);
3075 op1
= substitute_in_expr (TREE_OPERAND (exp
, 1), f
, r
);
3076 op2
= substitute_in_expr (TREE_OPERAND (exp
, 2), f
, r
);
3077 if (op0
== TREE_OPERAND (exp
, 0) && op1
== TREE_OPERAND (exp
, 1)
3078 && op2
== TREE_OPERAND (exp
, 2))
3081 new = fold (build (code
, TREE_TYPE (exp
), op0
, op1
, op2
));
3086 op0
= substitute_in_expr (TREE_OPERAND (exp
, 0), f
, r
);
3087 if (op0
== TREE_OPERAND (exp
, 0))
3090 new = fold (build1 (code
, TREE_TYPE (exp
), op0
));
3102 TREE_READONLY (new) = TREE_READONLY (exp
);
3106 /* Stabilize a reference so that we can use it any number of times
3107 without causing its operands to be evaluated more than once.
3108 Returns the stabilized reference. This works by means of save_expr,
3109 so see the caveats in the comments about save_expr.
3111 Also allows conversion expressions whose operands are references.
3112 Any other kind of expression is returned unchanged. */
3115 stabilize_reference (ref
)
3118 register tree result
;
3119 register enum tree_code code
= TREE_CODE (ref
);
3126 /* No action is needed in this case. */
3132 case FIX_TRUNC_EXPR
:
3133 case FIX_FLOOR_EXPR
:
3134 case FIX_ROUND_EXPR
:
3136 result
= build_nt (code
, stabilize_reference (TREE_OPERAND (ref
, 0)));
3140 result
= build_nt (INDIRECT_REF
,
3141 stabilize_reference_1 (TREE_OPERAND (ref
, 0)));
3145 result
= build_nt (COMPONENT_REF
,
3146 stabilize_reference (TREE_OPERAND (ref
, 0)),
3147 TREE_OPERAND (ref
, 1));
3151 result
= build_nt (BIT_FIELD_REF
,
3152 stabilize_reference (TREE_OPERAND (ref
, 0)),
3153 stabilize_reference_1 (TREE_OPERAND (ref
, 1)),
3154 stabilize_reference_1 (TREE_OPERAND (ref
, 2)));
3158 result
= build_nt (ARRAY_REF
,
3159 stabilize_reference (TREE_OPERAND (ref
, 0)),
3160 stabilize_reference_1 (TREE_OPERAND (ref
, 1)));
3164 /* We cannot wrap the first expression in a SAVE_EXPR, as then
3165 it wouldn't be ignored. This matters when dealing with
3167 return stabilize_reference_1 (ref
);
3170 result
= build1 (INDIRECT_REF
, TREE_TYPE (ref
),
3171 save_expr (build1 (ADDR_EXPR
,
3172 build_pointer_type (TREE_TYPE (ref
)),
3177 /* If arg isn't a kind of lvalue we recognize, make no change.
3178 Caller should recognize the error for an invalid lvalue. */
3183 return error_mark_node
;
3186 TREE_TYPE (result
) = TREE_TYPE (ref
);
3187 TREE_READONLY (result
) = TREE_READONLY (ref
);
3188 TREE_SIDE_EFFECTS (result
) = TREE_SIDE_EFFECTS (ref
);
3189 TREE_THIS_VOLATILE (result
) = TREE_THIS_VOLATILE (ref
);
3194 /* Subroutine of stabilize_reference; this is called for subtrees of
3195 references. Any expression with side-effects must be put in a SAVE_EXPR
3196 to ensure that it is only evaluated once.
3198 We don't put SAVE_EXPR nodes around everything, because assigning very
3199 simple expressions to temporaries causes us to miss good opportunities
3200 for optimizations. Among other things, the opportunity to fold in the
3201 addition of a constant into an addressing mode often gets lost, e.g.
3202 "y[i+1] += x;". In general, we take the approach that we should not make
3203 an assignment unless we are forced into it - i.e., that any non-side effect
3204 operator should be allowed, and that cse should take care of coalescing
3205 multiple utterances of the same expression should that prove fruitful. */
3208 stabilize_reference_1 (e
)
3211 register tree result
;
3212 register enum tree_code code
= TREE_CODE (e
);
3214 /* We cannot ignore const expressions because it might be a reference
3215 to a const array but whose index contains side-effects. But we can
3216 ignore things that are actual constant or that already have been
3217 handled by this function. */
3219 if (TREE_CONSTANT (e
) || code
== SAVE_EXPR
)
3222 switch (TREE_CODE_CLASS (code
))
3232 /* If the expression has side-effects, then encase it in a SAVE_EXPR
3233 so that it will only be evaluated once. */
3234 /* The reference (r) and comparison (<) classes could be handled as
3235 below, but it is generally faster to only evaluate them once. */
3236 if (TREE_SIDE_EFFECTS (e
))
3237 return save_expr (e
);
3241 /* Constants need no processing. In fact, we should never reach
3246 /* Division is slow and tends to be compiled with jumps,
3247 especially the division by powers of 2 that is often
3248 found inside of an array reference. So do it just once. */
3249 if (code
== TRUNC_DIV_EXPR
|| code
== TRUNC_MOD_EXPR
3250 || code
== FLOOR_DIV_EXPR
|| code
== FLOOR_MOD_EXPR
3251 || code
== CEIL_DIV_EXPR
|| code
== CEIL_MOD_EXPR
3252 || code
== ROUND_DIV_EXPR
|| code
== ROUND_MOD_EXPR
)
3253 return save_expr (e
);
3254 /* Recursively stabilize each operand. */
3255 result
= build_nt (code
, stabilize_reference_1 (TREE_OPERAND (e
, 0)),
3256 stabilize_reference_1 (TREE_OPERAND (e
, 1)));
3260 /* Recursively stabilize each operand. */
3261 result
= build_nt (code
, stabilize_reference_1 (TREE_OPERAND (e
, 0)));
3268 TREE_TYPE (result
) = TREE_TYPE (e
);
3269 TREE_READONLY (result
) = TREE_READONLY (e
);
3270 TREE_SIDE_EFFECTS (result
) = TREE_SIDE_EFFECTS (e
);
3271 TREE_THIS_VOLATILE (result
) = TREE_THIS_VOLATILE (e
);
3276 /* Low-level constructors for expressions. */
3278 /* Build an expression of code CODE, data type TYPE,
3279 and operands as specified by the arguments ARG1 and following arguments.
3280 Expressions and reference nodes can be created this way.
3281 Constants, decls, types and misc nodes cannot be. */
3284 build
VPARAMS ((enum tree_code code
, tree tt
, ...))
3286 #ifndef ANSI_PROTOTYPES
3287 enum tree_code code
;
3292 register int length
;
3298 #ifndef ANSI_PROTOTYPES
3299 code
= va_arg (p
, enum tree_code
);
3300 tt
= va_arg (p
, tree
);
3303 t
= make_node (code
);
3304 length
= tree_code_length
[(int) code
];
3307 /* Below, we automatically set TREE_SIDE_EFFECTS and TREE_RAISED for
3308 the result based on those same flags for the arguments. But, if
3309 the arguments aren't really even `tree' expressions, we shouldn't
3310 be trying to do this. */
3311 fro
= first_rtl_op (code
);
3315 /* This is equivalent to the loop below, but faster. */
3316 register tree arg0
= va_arg (p
, tree
);
3317 register tree arg1
= va_arg (p
, tree
);
3318 TREE_OPERAND (t
, 0) = arg0
;
3319 TREE_OPERAND (t
, 1) = arg1
;
3320 if (arg0
&& fro
> 0)
3322 if (TREE_SIDE_EFFECTS (arg0
))
3323 TREE_SIDE_EFFECTS (t
) = 1;
3325 if (arg1
&& fro
> 1)
3327 if (TREE_SIDE_EFFECTS (arg1
))
3328 TREE_SIDE_EFFECTS (t
) = 1;
3331 else if (length
== 1)
3333 register tree arg0
= va_arg (p
, tree
);
3335 /* Call build1 for this! */
3336 if (TREE_CODE_CLASS (code
) != 's')
3338 TREE_OPERAND (t
, 0) = arg0
;
3341 if (arg0
&& TREE_SIDE_EFFECTS (arg0
))
3342 TREE_SIDE_EFFECTS (t
) = 1;
3347 for (i
= 0; i
< length
; i
++)
3349 register tree operand
= va_arg (p
, tree
);
3350 TREE_OPERAND (t
, i
) = operand
;
3351 if (operand
&& fro
> i
)
3353 if (TREE_SIDE_EFFECTS (operand
))
3354 TREE_SIDE_EFFECTS (t
) = 1;
3362 /* Same as above, but only builds for unary operators.
3363 Saves lions share of calls to `build'; cuts down use
3364 of varargs, which is expensive for RISC machines. */
3367 build1 (code
, type
, node
)
3368 enum tree_code code
;
3372 register struct obstack
*obstack
= expression_obstack
;
3373 register int length
;
3374 #ifdef GATHER_STATISTICS
3375 register tree_node_kind kind
;
3379 #ifdef GATHER_STATISTICS
3380 if (TREE_CODE_CLASS (code
) == 'r')
3386 length
= sizeof (struct tree_exp
);
3389 t
= ggc_alloc_tree (length
);
3392 t
= (tree
) obstack_alloc (obstack
, length
);
3393 memset ((PTR
) t
, 0, length
);
3396 #ifdef GATHER_STATISTICS
3397 tree_node_counts
[(int)kind
]++;
3398 tree_node_sizes
[(int)kind
] += length
;
3401 TREE_TYPE (t
) = type
;
3402 TREE_SET_CODE (t
, code
);
3403 TREE_SET_PERMANENT (t
);
3405 TREE_OPERAND (t
, 0) = node
;
3406 if (node
&& first_rtl_op (code
) != 0 && TREE_SIDE_EFFECTS (node
))
3407 TREE_SIDE_EFFECTS (t
) = 1;
3415 case PREDECREMENT_EXPR
:
3416 case PREINCREMENT_EXPR
:
3417 case POSTDECREMENT_EXPR
:
3418 case POSTINCREMENT_EXPR
:
3419 /* All of these have side-effects, no matter what their
3421 TREE_SIDE_EFFECTS (t
) = 1;
3431 /* Similar except don't specify the TREE_TYPE
3432 and leave the TREE_SIDE_EFFECTS as 0.
3433 It is permissible for arguments to be null,
3434 or even garbage if their values do not matter. */
3437 build_nt
VPARAMS ((enum tree_code code
, ...))
3439 #ifndef ANSI_PROTOTYPES
3440 enum tree_code code
;
3444 register int length
;
3449 #ifndef ANSI_PROTOTYPES
3450 code
= va_arg (p
, enum tree_code
);
3453 t
= make_node (code
);
3454 length
= tree_code_length
[(int) code
];
3456 for (i
= 0; i
< length
; i
++)
3457 TREE_OPERAND (t
, i
) = va_arg (p
, tree
);
3463 /* Similar to `build_nt', except we build
3464 on the temp_decl_obstack, regardless. */
3467 build_parse_node
VPARAMS ((enum tree_code code
, ...))
3469 #ifndef ANSI_PROTOTYPES
3470 enum tree_code code
;
3472 register struct obstack
*ambient_obstack
= expression_obstack
;
3475 register int length
;
3480 #ifndef ANSI_PROTOTYPES
3481 code
= va_arg (p
, enum tree_code
);
3484 expression_obstack
= &temp_decl_obstack
;
3486 t
= make_node (code
);
3487 length
= tree_code_length
[(int) code
];
3489 for (i
= 0; i
< length
; i
++)
3490 TREE_OPERAND (t
, i
) = va_arg (p
, tree
);
3493 expression_obstack
= ambient_obstack
;
3498 /* Commented out because this wants to be done very
3499 differently. See cp-lex.c. */
3501 build_op_identifier (op1
, op2
)
3504 register tree t
= make_node (OP_IDENTIFIER
);
3505 TREE_PURPOSE (t
) = op1
;
3506 TREE_VALUE (t
) = op2
;
3511 /* Create a DECL_... node of code CODE, name NAME and data type TYPE.
3512 We do NOT enter this node in any sort of symbol table.
3514 layout_decl is used to set up the decl's storage layout.
3515 Other slots are initialized to 0 or null pointers. */
3518 build_decl (code
, name
, type
)
3519 enum tree_code code
;
3524 t
= make_node (code
);
3526 /* if (type == error_mark_node)
3527 type = integer_type_node; */
3528 /* That is not done, deliberately, so that having error_mark_node
3529 as the type can suppress useless errors in the use of this variable. */
3531 DECL_NAME (t
) = name
;
3532 DECL_ASSEMBLER_NAME (t
) = name
;
3533 TREE_TYPE (t
) = type
;
3535 if (code
== VAR_DECL
|| code
== PARM_DECL
|| code
== RESULT_DECL
)
3537 else if (code
== FUNCTION_DECL
)
3538 DECL_MODE (t
) = FUNCTION_MODE
;
3543 /* BLOCK nodes are used to represent the structure of binding contours
3544 and declarations, once those contours have been exited and their contents
3545 compiled. This information is used for outputting debugging info. */
3548 build_block (vars
, tags
, subblocks
, supercontext
, chain
)
3549 tree vars
, tags ATTRIBUTE_UNUSED
, subblocks
, supercontext
, chain
;
3551 register tree block
= make_node (BLOCK
);
3553 BLOCK_VARS (block
) = vars
;
3554 BLOCK_SUBBLOCKS (block
) = subblocks
;
3555 BLOCK_SUPERCONTEXT (block
) = supercontext
;
3556 BLOCK_CHAIN (block
) = chain
;
3560 /* EXPR_WITH_FILE_LOCATION are used to keep track of the exact
3561 location where an expression or an identifier were encountered. It
3562 is necessary for languages where the frontend parser will handle
3563 recursively more than one file (Java is one of them). */
3566 build_expr_wfl (node
, file
, line
, col
)
3571 static const char *last_file
= 0;
3572 static tree last_filenode
= NULL_TREE
;
3573 register tree wfl
= make_node (EXPR_WITH_FILE_LOCATION
);
3575 EXPR_WFL_NODE (wfl
) = node
;
3576 EXPR_WFL_SET_LINECOL (wfl
, line
, col
);
3577 if (file
!= last_file
)
3580 last_filenode
= file
? get_identifier (file
) : NULL_TREE
;
3583 EXPR_WFL_FILENAME_NODE (wfl
) = last_filenode
;
3586 TREE_SIDE_EFFECTS (wfl
) = TREE_SIDE_EFFECTS (node
);
3587 TREE_TYPE (wfl
) = TREE_TYPE (node
);
3593 /* Return a declaration like DDECL except that its DECL_MACHINE_ATTRIBUTE
3597 build_decl_attribute_variant (ddecl
, attribute
)
3598 tree ddecl
, attribute
;
3600 DECL_MACHINE_ATTRIBUTES (ddecl
) = attribute
;
3604 /* Return a type like TTYPE except that its TYPE_ATTRIBUTE
3607 Record such modified types already made so we don't make duplicates. */
3610 build_type_attribute_variant (ttype
, attribute
)
3611 tree ttype
, attribute
;
3613 if ( ! attribute_list_equal (TYPE_ATTRIBUTES (ttype
), attribute
))
3615 unsigned int hashcode
;
3618 push_obstacks (TYPE_OBSTACK (ttype
), TYPE_OBSTACK (ttype
));
3619 ntype
= copy_node (ttype
);
3621 TYPE_POINTER_TO (ntype
) = 0;
3622 TYPE_REFERENCE_TO (ntype
) = 0;
3623 TYPE_ATTRIBUTES (ntype
) = attribute
;
3625 /* Create a new main variant of TYPE. */
3626 TYPE_MAIN_VARIANT (ntype
) = ntype
;
3627 TYPE_NEXT_VARIANT (ntype
) = 0;
3628 set_type_quals (ntype
, TYPE_UNQUALIFIED
);
3630 hashcode
= (TYPE_HASH (TREE_CODE (ntype
))
3631 + TYPE_HASH (TREE_TYPE (ntype
))
3632 + attribute_hash_list (attribute
));
3634 switch (TREE_CODE (ntype
))
3637 hashcode
+= TYPE_HASH (TYPE_ARG_TYPES (ntype
));
3640 hashcode
+= TYPE_HASH (TYPE_DOMAIN (ntype
));
3643 hashcode
+= TYPE_HASH (TYPE_MAX_VALUE (ntype
));
3646 hashcode
+= TYPE_HASH (TYPE_PRECISION (ntype
));
3652 ntype
= type_hash_canon (hashcode
, ntype
);
3653 ttype
= build_qualified_type (ntype
, TYPE_QUALS (ttype
));
3660 /* Return a 1 if ATTR_NAME and ATTR_ARGS is valid for either declaration DECL
3661 or type TYPE and 0 otherwise. Validity is determined the configuration
3662 macros VALID_MACHINE_DECL_ATTRIBUTE and VALID_MACHINE_TYPE_ATTRIBUTE. */
3665 valid_machine_attribute (attr_name
, attr_args
, decl
, type
)
3667 tree attr_args ATTRIBUTE_UNUSED
;
3668 tree decl ATTRIBUTE_UNUSED
;
3669 tree type ATTRIBUTE_UNUSED
;
3672 #ifdef VALID_MACHINE_DECL_ATTRIBUTE
3673 tree decl_attr_list
= decl
!= 0 ? DECL_MACHINE_ATTRIBUTES (decl
) : 0;
3675 #ifdef VALID_MACHINE_TYPE_ATTRIBUTE
3676 tree type_attr_list
= TYPE_ATTRIBUTES (type
);
3679 if (TREE_CODE (attr_name
) != IDENTIFIER_NODE
)
3682 #ifdef VALID_MACHINE_DECL_ATTRIBUTE
3684 && VALID_MACHINE_DECL_ATTRIBUTE (decl
, decl_attr_list
, attr_name
,
3687 tree attr
= lookup_attribute (IDENTIFIER_POINTER (attr_name
),
3690 if (attr
!= NULL_TREE
)
3692 /* Override existing arguments. Declarations are unique so we can
3693 modify this in place. */
3694 TREE_VALUE (attr
) = attr_args
;
3698 decl_attr_list
= tree_cons (attr_name
, attr_args
, decl_attr_list
);
3699 decl
= build_decl_attribute_variant (decl
, decl_attr_list
);
3706 #ifdef VALID_MACHINE_TYPE_ATTRIBUTE
3708 /* Don't apply the attribute to both the decl and the type. */;
3709 else if (VALID_MACHINE_TYPE_ATTRIBUTE (type
, type_attr_list
, attr_name
,
3712 tree attr
= lookup_attribute (IDENTIFIER_POINTER (attr_name
),
3715 if (attr
!= NULL_TREE
)
3717 /* Override existing arguments.
3718 ??? This currently works since attribute arguments are not
3719 included in `attribute_hash_list'. Something more complicated
3720 may be needed in the future. */
3721 TREE_VALUE (attr
) = attr_args
;
3725 /* If this is part of a declaration, create a type variant,
3726 otherwise, this is part of a type definition, so add it
3727 to the base type. */
3728 type_attr_list
= tree_cons (attr_name
, attr_args
, type_attr_list
);
3730 type
= build_type_attribute_variant (type
, type_attr_list
);
3732 TYPE_ATTRIBUTES (type
) = type_attr_list
;
3736 TREE_TYPE (decl
) = type
;
3741 /* Handle putting a type attribute on pointer-to-function-type by putting
3742 the attribute on the function type. */
3743 else if (POINTER_TYPE_P (type
)
3744 && TREE_CODE (TREE_TYPE (type
)) == FUNCTION_TYPE
3745 && VALID_MACHINE_TYPE_ATTRIBUTE (TREE_TYPE (type
), type_attr_list
,
3746 attr_name
, attr_args
))
3748 tree inner_type
= TREE_TYPE (type
);
3749 tree inner_attr_list
= TYPE_ATTRIBUTES (inner_type
);
3750 tree attr
= lookup_attribute (IDENTIFIER_POINTER (attr_name
),
3753 if (attr
!= NULL_TREE
)
3754 TREE_VALUE (attr
) = attr_args
;
3757 inner_attr_list
= tree_cons (attr_name
, attr_args
, inner_attr_list
);
3758 inner_type
= build_type_attribute_variant (inner_type
,
3763 TREE_TYPE (decl
) = build_pointer_type (inner_type
);
3766 /* Clear TYPE_POINTER_TO for the old inner type, since
3767 `type' won't be pointing to it anymore. */
3768 TYPE_POINTER_TO (TREE_TYPE (type
)) = NULL_TREE
;
3769 TREE_TYPE (type
) = inner_type
;
3779 /* Return non-zero if IDENT is a valid name for attribute ATTR,
3782 We try both `text' and `__text__', ATTR may be either one. */
3783 /* ??? It might be a reasonable simplification to require ATTR to be only
3784 `text'. One might then also require attribute lists to be stored in
3785 their canonicalized form. */
3788 is_attribute_p (attr
, ident
)
3792 int ident_len
, attr_len
;
3795 if (TREE_CODE (ident
) != IDENTIFIER_NODE
)
3798 if (strcmp (attr
, IDENTIFIER_POINTER (ident
)) == 0)
3801 p
= IDENTIFIER_POINTER (ident
);
3802 ident_len
= strlen (p
);
3803 attr_len
= strlen (attr
);
3805 /* If ATTR is `__text__', IDENT must be `text'; and vice versa. */
3809 || attr
[attr_len
- 2] != '_'
3810 || attr
[attr_len
- 1] != '_')
3812 if (ident_len
== attr_len
- 4
3813 && strncmp (attr
+ 2, p
, attr_len
- 4) == 0)
3818 if (ident_len
== attr_len
+ 4
3819 && p
[0] == '_' && p
[1] == '_'
3820 && p
[ident_len
- 2] == '_' && p
[ident_len
- 1] == '_'
3821 && strncmp (attr
, p
+ 2, attr_len
) == 0)
3828 /* Given an attribute name and a list of attributes, return a pointer to the
3829 attribute's list element if the attribute is part of the list, or NULL_TREE
3833 lookup_attribute (attr_name
, list
)
3834 const char *attr_name
;
3839 for (l
= list
; l
; l
= TREE_CHAIN (l
))
3841 if (TREE_CODE (TREE_PURPOSE (l
)) != IDENTIFIER_NODE
)
3843 if (is_attribute_p (attr_name
, TREE_PURPOSE (l
)))
3850 /* Return an attribute list that is the union of a1 and a2. */
3853 merge_attributes (a1
, a2
)
3854 register tree a1
, a2
;
3858 /* Either one unset? Take the set one. */
3860 if ((attributes
= a1
) == 0)
3863 /* One that completely contains the other? Take it. */
3865 else if (a2
!= 0 && ! attribute_list_contained (a1
, a2
))
3867 if (attribute_list_contained (a2
, a1
))
3871 /* Pick the longest list, and hang on the other list. */
3872 /* ??? For the moment we punt on the issue of attrs with args. */
3874 if (list_length (a1
) < list_length (a2
))
3875 attributes
= a2
, a2
= a1
;
3877 for (; a2
!= 0; a2
= TREE_CHAIN (a2
))
3878 if (lookup_attribute (IDENTIFIER_POINTER (TREE_PURPOSE (a2
)),
3879 attributes
) == NULL_TREE
)
3881 a1
= copy_node (a2
);
3882 TREE_CHAIN (a1
) = attributes
;
3890 /* Given types T1 and T2, merge their attributes and return
3894 merge_machine_type_attributes (t1
, t2
)
3897 #ifdef MERGE_MACHINE_TYPE_ATTRIBUTES
3898 return MERGE_MACHINE_TYPE_ATTRIBUTES (t1
, t2
);
3900 return merge_attributes (TYPE_ATTRIBUTES (t1
),
3901 TYPE_ATTRIBUTES (t2
));
3905 /* Given decls OLDDECL and NEWDECL, merge their attributes and return
3909 merge_machine_decl_attributes (olddecl
, newdecl
)
3910 tree olddecl
, newdecl
;
3912 #ifdef MERGE_MACHINE_DECL_ATTRIBUTES
3913 return MERGE_MACHINE_DECL_ATTRIBUTES (olddecl
, newdecl
);
3915 return merge_attributes (DECL_MACHINE_ATTRIBUTES (olddecl
),
3916 DECL_MACHINE_ATTRIBUTES (newdecl
));
3920 /* Set the type qualifiers for TYPE to TYPE_QUALS, which is a bitmask
3921 of the various TYPE_QUAL values. */
3924 set_type_quals (type
, type_quals
)
3928 TYPE_READONLY (type
) = (type_quals
& TYPE_QUAL_CONST
) != 0;
3929 TYPE_VOLATILE (type
) = (type_quals
& TYPE_QUAL_VOLATILE
) != 0;
3930 TYPE_RESTRICT (type
) = (type_quals
& TYPE_QUAL_RESTRICT
) != 0;
3933 /* Given a type node TYPE and a TYPE_QUALIFIER_SET, return a type for
3934 the same kind of data as TYPE describes. Variants point to the
3935 "main variant" (which has no qualifiers set) via TYPE_MAIN_VARIANT,
3936 and it points to a chain of other variants so that duplicate
3937 variants are never made. Only main variants should ever appear as
3938 types of expressions. */
3941 build_qualified_type (type
, type_quals
)
3947 /* Search the chain of variants to see if there is already one there just
3948 like the one we need to have. If so, use that existing one. We must
3949 preserve the TYPE_NAME, since there is code that depends on this. */
3951 for (t
= TYPE_MAIN_VARIANT (type
); t
; t
= TYPE_NEXT_VARIANT (t
))
3952 if (TYPE_QUALS (t
) == type_quals
&& TYPE_NAME (t
) == TYPE_NAME (type
))
3955 /* We need a new one. */
3956 t
= build_type_copy (type
);
3957 set_type_quals (t
, type_quals
);
3961 /* Create a new variant of TYPE, equivalent but distinct.
3962 This is so the caller can modify it. */
3965 build_type_copy (type
)
3968 register tree t
, m
= TYPE_MAIN_VARIANT (type
);
3969 register struct obstack
*ambient_obstack
= current_obstack
;
3971 current_obstack
= TYPE_OBSTACK (type
);
3972 t
= copy_node (type
);
3973 current_obstack
= ambient_obstack
;
3975 TYPE_POINTER_TO (t
) = 0;
3976 TYPE_REFERENCE_TO (t
) = 0;
3978 /* Add this type to the chain of variants of TYPE. */
3979 TYPE_NEXT_VARIANT (t
) = TYPE_NEXT_VARIANT (m
);
3980 TYPE_NEXT_VARIANT (m
) = t
;
3985 /* Hashing of types so that we don't make duplicates.
3986 The entry point is `type_hash_canon'. */
3988 /* Compute a hash code for a list of types (chain of TREE_LIST nodes
3989 with types in the TREE_VALUE slots), by adding the hash codes
3990 of the individual types. */
3993 type_hash_list (list
)
3996 unsigned int hashcode
;
3999 for (hashcode
= 0, tail
= list
; tail
; tail
= TREE_CHAIN (tail
))
4000 hashcode
+= TYPE_HASH (TREE_VALUE (tail
));
4005 /* These are the Hashtable callback functions. */
4007 /* Returns true if the types are equal. */
4010 type_hash_eq (va
, vb
)
4014 const struct type_hash
*a
= va
, *b
= vb
;
4015 if (a
->hash
== b
->hash
4016 && TREE_CODE (a
->type
) == TREE_CODE (b
->type
)
4017 && TREE_TYPE (a
->type
) == TREE_TYPE (b
->type
)
4018 && attribute_list_equal (TYPE_ATTRIBUTES (a
->type
),
4019 TYPE_ATTRIBUTES (b
->type
))
4020 && TYPE_ALIGN (a
->type
) == TYPE_ALIGN (b
->type
)
4021 && (TYPE_MAX_VALUE (a
->type
) == TYPE_MAX_VALUE (b
->type
)
4022 || tree_int_cst_equal (TYPE_MAX_VALUE (a
->type
),
4023 TYPE_MAX_VALUE (b
->type
)))
4024 && (TYPE_MIN_VALUE (a
->type
) == TYPE_MIN_VALUE (b
->type
)
4025 || tree_int_cst_equal (TYPE_MIN_VALUE (a
->type
),
4026 TYPE_MIN_VALUE (b
->type
)))
4027 /* Note that TYPE_DOMAIN is TYPE_ARG_TYPES for FUNCTION_TYPE. */
4028 && (TYPE_DOMAIN (a
->type
) == TYPE_DOMAIN (b
->type
)
4029 || (TYPE_DOMAIN (a
->type
)
4030 && TREE_CODE (TYPE_DOMAIN (a
->type
)) == TREE_LIST
4031 && TYPE_DOMAIN (b
->type
)
4032 && TREE_CODE (TYPE_DOMAIN (b
->type
)) == TREE_LIST
4033 && type_list_equal (TYPE_DOMAIN (a
->type
),
4034 TYPE_DOMAIN (b
->type
)))))
4039 /* Return the cached hash value. */
4042 type_hash_hash (item
)
4045 return ((const struct type_hash
*)item
)->hash
;
4048 /* Look in the type hash table for a type isomorphic to TYPE.
4049 If one is found, return it. Otherwise return 0. */
4052 type_hash_lookup (hashcode
, type
)
4053 unsigned int hashcode
;
4056 struct type_hash
*h
, in
;
4058 /* The TYPE_ALIGN field of a type is set by layout_type(), so we
4059 must call that routine before comparing TYPE_ALIGNs. */
4065 h
= htab_find_with_hash (type_hash_table
, &in
, hashcode
);
4071 /* Add an entry to the type-hash-table
4072 for a type TYPE whose hash code is HASHCODE. */
4075 type_hash_add (hashcode
, type
)
4076 unsigned int hashcode
;
4079 struct type_hash
*h
;
4082 h
= (struct type_hash
*) permalloc (sizeof (struct type_hash
));
4085 loc
= htab_find_slot_with_hash (type_hash_table
, h
, hashcode
, INSERT
);
4086 *(struct type_hash
**) loc
= h
;
4089 /* Given TYPE, and HASHCODE its hash code, return the canonical
4090 object for an identical type if one already exists.
4091 Otherwise, return TYPE, and record it as the canonical object
4092 if it is a permanent object.
4094 To use this function, first create a type of the sort you want.
4095 Then compute its hash code from the fields of the type that
4096 make it different from other similar types.
4097 Then call this function and use the value.
4098 This function frees the type you pass in if it is a duplicate. */
4100 /* Set to 1 to debug without canonicalization. Never set by program. */
4101 int debug_no_type_hash
= 0;
4104 type_hash_canon (hashcode
, type
)
4105 unsigned int hashcode
;
4110 if (debug_no_type_hash
)
4113 t1
= type_hash_lookup (hashcode
, type
);
4117 obstack_free (TYPE_OBSTACK (type
), type
);
4119 #ifdef GATHER_STATISTICS
4120 tree_node_counts
[(int) t_kind
]--;
4121 tree_node_sizes
[(int) t_kind
] -= sizeof (struct tree_type
);
4126 /* If this is a permanent type, record it for later reuse. */
4127 if (ggc_p
|| TREE_PERMANENT (type
))
4128 type_hash_add (hashcode
, type
);
4133 /* Callback function for htab_traverse. */
4136 mark_hash_entry (entry
, param
)
4138 void *param ATTRIBUTE_UNUSED
;
4140 struct type_hash
*p
= *(struct type_hash
**)entry
;
4142 ggc_mark_tree (p
->type
);
4144 /* Continue scan. */
4148 /* Mark ARG (which is really a htab_t *) for GC. */
4151 mark_type_hash (arg
)
4154 htab_t t
= *(htab_t
*) arg
;
4156 htab_traverse (t
, mark_hash_entry
, 0);
4160 print_type_hash_statistics ()
4162 fprintf (stderr
, "Type hash: size %ld, %ld elements, %f collisions\n",
4163 (long) htab_size (type_hash_table
),
4164 (long) htab_elements (type_hash_table
),
4165 htab_collisions (type_hash_table
));
4168 /* Compute a hash code for a list of attributes (chain of TREE_LIST nodes
4169 with names in the TREE_PURPOSE slots and args in the TREE_VALUE slots),
4170 by adding the hash codes of the individual attributes. */
4173 attribute_hash_list (list
)
4176 unsigned int hashcode
;
4179 for (hashcode
= 0, tail
= list
; tail
; tail
= TREE_CHAIN (tail
))
4180 /* ??? Do we want to add in TREE_VALUE too? */
4181 hashcode
+= TYPE_HASH (TREE_PURPOSE (tail
));
4185 /* Given two lists of attributes, return true if list l2 is
4186 equivalent to l1. */
4189 attribute_list_equal (l1
, l2
)
4192 return attribute_list_contained (l1
, l2
)
4193 && attribute_list_contained (l2
, l1
);
4196 /* Given two lists of attributes, return true if list L2 is
4197 completely contained within L1. */
4198 /* ??? This would be faster if attribute names were stored in a canonicalized
4199 form. Otherwise, if L1 uses `foo' and L2 uses `__foo__', the long method
4200 must be used to show these elements are equivalent (which they are). */
4201 /* ??? It's not clear that attributes with arguments will always be handled
4205 attribute_list_contained (l1
, l2
)
4208 register tree t1
, t2
;
4210 /* First check the obvious, maybe the lists are identical. */
4214 /* Maybe the lists are similar. */
4215 for (t1
= l1
, t2
= l2
;
4217 && TREE_PURPOSE (t1
) == TREE_PURPOSE (t2
)
4218 && TREE_VALUE (t1
) == TREE_VALUE (t2
);
4219 t1
= TREE_CHAIN (t1
), t2
= TREE_CHAIN (t2
));
4221 /* Maybe the lists are equal. */
4222 if (t1
== 0 && t2
== 0)
4225 for (; t2
!= 0; t2
= TREE_CHAIN (t2
))
4228 = lookup_attribute (IDENTIFIER_POINTER (TREE_PURPOSE (t2
)), l1
);
4233 if (simple_cst_equal (TREE_VALUE (t2
), TREE_VALUE (attr
)) != 1)
4240 /* Given two lists of types
4241 (chains of TREE_LIST nodes with types in the TREE_VALUE slots)
4242 return 1 if the lists contain the same types in the same order.
4243 Also, the TREE_PURPOSEs must match. */
4246 type_list_equal (l1
, l2
)
4249 register tree t1
, t2
;
4251 for (t1
= l1
, t2
= l2
; t1
&& t2
; t1
= TREE_CHAIN (t1
), t2
= TREE_CHAIN (t2
))
4252 if (TREE_VALUE (t1
) != TREE_VALUE (t2
)
4253 || (TREE_PURPOSE (t1
) != TREE_PURPOSE (t2
)
4254 && ! (1 == simple_cst_equal (TREE_PURPOSE (t1
), TREE_PURPOSE (t2
))
4255 && (TREE_TYPE (TREE_PURPOSE (t1
))
4256 == TREE_TYPE (TREE_PURPOSE (t2
))))))
4262 /* Nonzero if integer constants T1 and T2
4263 represent the same constant value. */
4266 tree_int_cst_equal (t1
, t2
)
4272 if (t1
== 0 || t2
== 0)
4275 if (TREE_CODE (t1
) == INTEGER_CST
4276 && TREE_CODE (t2
) == INTEGER_CST
4277 && TREE_INT_CST_LOW (t1
) == TREE_INT_CST_LOW (t2
)
4278 && TREE_INT_CST_HIGH (t1
) == TREE_INT_CST_HIGH (t2
))
4284 /* Nonzero if integer constants T1 and T2 represent values that satisfy <.
4285 The precise way of comparison depends on their data type. */
4288 tree_int_cst_lt (t1
, t2
)
4294 if (! TREE_UNSIGNED (TREE_TYPE (t1
)))
4295 return INT_CST_LT (t1
, t2
);
4297 return INT_CST_LT_UNSIGNED (t1
, t2
);
4300 /* Return 1 if T is an INTEGER_CST that can be represented in a single
4301 HOST_WIDE_INT value. If POS is nonzero, the result must be positive. */
4304 host_integerp (t
, pos
)
4308 return (TREE_CODE (t
) == INTEGER_CST
4309 && ! TREE_OVERFLOW (t
)
4310 && ((TREE_INT_CST_HIGH (t
) == 0
4311 && (HOST_WIDE_INT
) TREE_INT_CST_LOW (t
) >= 0)
4312 || (! pos
&& TREE_INT_CST_HIGH (t
) == -1
4313 && (HOST_WIDE_INT
) TREE_INT_CST_LOW (t
) < 0)));
4316 /* Return the HOST_WIDE_INT least significant bits of T if it is an
4317 INTEGER_CST and there is no overflow. POS is nonzero if the result must
4318 be positive. Abort if we cannot satisfy the above conditions. */
4321 tree_low_cst (t
, pos
)
4325 if (host_integerp (t
, pos
))
4326 return TREE_INT_CST_LOW (t
);
4331 /* Return the most significant bit of the integer constant T. */
4334 tree_int_cst_msb (t
)
4339 unsigned HOST_WIDE_INT l
;
4341 /* Note that using TYPE_PRECISION here is wrong. We care about the
4342 actual bits, not the (arbitrary) range of the type. */
4343 prec
= GET_MODE_BITSIZE (TYPE_MODE (TREE_TYPE (t
))) - 1;
4344 rshift_double (TREE_INT_CST_LOW (t
), TREE_INT_CST_HIGH (t
), prec
,
4345 2 * HOST_BITS_PER_WIDE_INT
, &l
, &h
, 0);
4346 return (l
& 1) == 1;
4349 /* Return an indication of the sign of the integer constant T.
4350 The return value is -1 if T < 0, 0 if T == 0, and 1 if T > 0.
4351 Note that -1 will never be returned it T's type is unsigned. */
4354 tree_int_cst_sgn (t
)
4357 if (TREE_INT_CST_LOW (t
) == 0 && TREE_INT_CST_HIGH (t
) == 0)
4359 else if (TREE_UNSIGNED (TREE_TYPE (t
)))
4361 else if (TREE_INT_CST_HIGH (t
) < 0)
4367 /* Return true if `t' is known to be non-negative. */
4370 tree_expr_nonnegative_p (t
)
4373 switch (TREE_CODE (t
))
4376 return tree_int_cst_sgn (t
) >= 0;
4378 return tree_expr_nonnegative_p (TREE_OPERAND (t
, 1))
4379 && tree_expr_nonnegative_p (TREE_OPERAND (t
, 2));
4381 /* We don't know sign of `t', so be safe and return false. */
4386 /* Compare two constructor-element-type constants. Return 1 if the lists
4387 are known to be equal; otherwise return 0. */
4390 simple_cst_list_equal (l1
, l2
)
4393 while (l1
!= NULL_TREE
&& l2
!= NULL_TREE
)
4395 if (simple_cst_equal (TREE_VALUE (l1
), TREE_VALUE (l2
)) != 1)
4398 l1
= TREE_CHAIN (l1
);
4399 l2
= TREE_CHAIN (l2
);
4405 /* Return truthvalue of whether T1 is the same tree structure as T2.
4406 Return 1 if they are the same.
4407 Return 0 if they are understandably different.
4408 Return -1 if either contains tree structure not understood by
4412 simple_cst_equal (t1
, t2
)
4415 register enum tree_code code1
, code2
;
4421 if (t1
== 0 || t2
== 0)
4424 code1
= TREE_CODE (t1
);
4425 code2
= TREE_CODE (t2
);
4427 if (code1
== NOP_EXPR
|| code1
== CONVERT_EXPR
|| code1
== NON_LVALUE_EXPR
)
4429 if (code2
== NOP_EXPR
|| code2
== CONVERT_EXPR
4430 || code2
== NON_LVALUE_EXPR
)
4431 return simple_cst_equal (TREE_OPERAND (t1
, 0), TREE_OPERAND (t2
, 0));
4433 return simple_cst_equal (TREE_OPERAND (t1
, 0), t2
);
4436 else if (code2
== NOP_EXPR
|| code2
== CONVERT_EXPR
4437 || code2
== NON_LVALUE_EXPR
)
4438 return simple_cst_equal (t1
, TREE_OPERAND (t2
, 0));
4446 return (TREE_INT_CST_LOW (t1
) == TREE_INT_CST_LOW (t2
)
4447 && TREE_INT_CST_HIGH (t1
) == TREE_INT_CST_HIGH (t2
));
4450 return REAL_VALUES_IDENTICAL (TREE_REAL_CST (t1
), TREE_REAL_CST (t2
));
4453 return (TREE_STRING_LENGTH (t1
) == TREE_STRING_LENGTH (t2
)
4454 && ! bcmp (TREE_STRING_POINTER (t1
), TREE_STRING_POINTER (t2
),
4455 TREE_STRING_LENGTH (t1
)));
4458 if (CONSTRUCTOR_ELTS (t1
) == CONSTRUCTOR_ELTS (t2
))
4464 return simple_cst_equal (TREE_OPERAND (t1
, 0), TREE_OPERAND (t2
, 0));
4467 cmp
= simple_cst_equal (TREE_OPERAND (t1
, 0), TREE_OPERAND (t2
, 0));
4471 simple_cst_list_equal (TREE_OPERAND (t1
, 1), TREE_OPERAND (t2
, 1));
4474 /* Special case: if either target is an unallocated VAR_DECL,
4475 it means that it's going to be unified with whatever the
4476 TARGET_EXPR is really supposed to initialize, so treat it
4477 as being equivalent to anything. */
4478 if ((TREE_CODE (TREE_OPERAND (t1
, 0)) == VAR_DECL
4479 && DECL_NAME (TREE_OPERAND (t1
, 0)) == NULL_TREE
4480 && DECL_RTL (TREE_OPERAND (t1
, 0)) == 0)
4481 || (TREE_CODE (TREE_OPERAND (t2
, 0)) == VAR_DECL
4482 && DECL_NAME (TREE_OPERAND (t2
, 0)) == NULL_TREE
4483 && DECL_RTL (TREE_OPERAND (t2
, 0)) == 0))
4486 cmp
= simple_cst_equal (TREE_OPERAND (t1
, 0), TREE_OPERAND (t2
, 0));
4491 return simple_cst_equal (TREE_OPERAND (t1
, 1), TREE_OPERAND (t2
, 1));
4493 case WITH_CLEANUP_EXPR
:
4494 cmp
= simple_cst_equal (TREE_OPERAND (t1
, 0), TREE_OPERAND (t2
, 0));
4498 return simple_cst_equal (TREE_OPERAND (t1
, 2), TREE_OPERAND (t1
, 2));
4501 if (TREE_OPERAND (t1
, 1) == TREE_OPERAND (t2
, 1))
4502 return simple_cst_equal (TREE_OPERAND (t1
, 0), TREE_OPERAND (t2
, 0));
4516 /* This general rule works for most tree codes. All exceptions should be
4517 handled above. If this is a language-specific tree code, we can't
4518 trust what might be in the operand, so say we don't know
4520 if ((int) code1
>= (int) LAST_AND_UNUSED_TREE_CODE
)
4523 switch (TREE_CODE_CLASS (code1
))
4532 for (i
= 0; i
< tree_code_length
[(int) code1
]; i
++)
4534 cmp
= simple_cst_equal (TREE_OPERAND (t1
, i
), TREE_OPERAND (t2
, i
));
4546 /* Compare the value of T, an INTEGER_CST, with U, an unsigned integer value.
4547 Return -1, 0, or 1 if the value of T is less than, equal to, or greater
4548 than U, respectively. */
4551 compare_tree_int (t
, u
)
4555 if (tree_int_cst_sgn (t
) < 0)
4557 else if (TREE_INT_CST_HIGH (t
) != 0)
4559 else if (TREE_INT_CST_LOW (t
) == u
)
4561 else if (TREE_INT_CST_LOW (t
) < u
)
4567 /* Constructors for pointer, array and function types.
4568 (RECORD_TYPE, UNION_TYPE and ENUMERAL_TYPE nodes are
4569 constructed by language-dependent code, not here.) */
4571 /* Construct, lay out and return the type of pointers to TO_TYPE.
4572 If such a type has already been constructed, reuse it. */
4575 build_pointer_type (to_type
)
4578 register tree t
= TYPE_POINTER_TO (to_type
);
4580 /* First, if we already have a type for pointers to TO_TYPE, use it. */
4585 /* We need a new one. Put this in the same obstack as TO_TYPE. */
4586 push_obstacks (TYPE_OBSTACK (to_type
), TYPE_OBSTACK (to_type
));
4587 t
= make_node (POINTER_TYPE
);
4590 TREE_TYPE (t
) = to_type
;
4592 /* Record this type as the pointer to TO_TYPE. */
4593 TYPE_POINTER_TO (to_type
) = t
;
4595 /* Lay out the type. This function has many callers that are concerned
4596 with expression-construction, and this simplifies them all.
4597 Also, it guarantees the TYPE_SIZE is in the same obstack as the type. */
4603 /* Build the node for the type of references-to-TO_TYPE. */
4606 build_reference_type (to_type
)
4609 register tree t
= TYPE_REFERENCE_TO (to_type
);
4611 /* First, if we already have a type for pointers to TO_TYPE, use it. */
4616 /* We need a new one. Put this in the same obstack as TO_TYPE. */
4617 push_obstacks (TYPE_OBSTACK (to_type
), TYPE_OBSTACK (to_type
));
4618 t
= make_node (REFERENCE_TYPE
);
4621 TREE_TYPE (t
) = to_type
;
4623 /* Record this type as the pointer to TO_TYPE. */
4624 TYPE_REFERENCE_TO (to_type
) = t
;
4631 /* Create a type of integers to be the TYPE_DOMAIN of an ARRAY_TYPE.
4632 MAXVAL should be the maximum value in the domain
4633 (one less than the length of the array).
4635 The maximum value that MAXVAL can have is INT_MAX for a HOST_WIDE_INT.
4636 We don't enforce this limit, that is up to caller (e.g. language front end).
4637 The limit exists because the result is a signed type and we don't handle
4638 sizes that use more than one HOST_WIDE_INT. */
4641 build_index_type (maxval
)
4644 register tree itype
= make_node (INTEGER_TYPE
);
4646 TREE_TYPE (itype
) = sizetype
;
4647 TYPE_PRECISION (itype
) = TYPE_PRECISION (sizetype
);
4648 TYPE_MIN_VALUE (itype
) = size_zero_node
;
4650 push_obstacks (TYPE_OBSTACK (itype
), TYPE_OBSTACK (itype
));
4651 TYPE_MAX_VALUE (itype
) = convert (sizetype
, maxval
);
4654 TYPE_MODE (itype
) = TYPE_MODE (sizetype
);
4655 TYPE_SIZE (itype
) = TYPE_SIZE (sizetype
);
4656 TYPE_SIZE_UNIT (itype
) = TYPE_SIZE_UNIT (sizetype
);
4657 TYPE_ALIGN (itype
) = TYPE_ALIGN (sizetype
);
4659 if (host_integerp (maxval
, 1))
4660 return type_hash_canon (tree_low_cst (maxval
, 1), itype
);
4665 /* Create a range of some discrete type TYPE (an INTEGER_TYPE,
4666 ENUMERAL_TYPE, BOOLEAN_TYPE, or CHAR_TYPE), with
4667 low bound LOWVAL and high bound HIGHVAL.
4668 if TYPE==NULL_TREE, sizetype is used. */
4671 build_range_type (type
, lowval
, highval
)
4672 tree type
, lowval
, highval
;
4674 register tree itype
= make_node (INTEGER_TYPE
);
4676 TREE_TYPE (itype
) = type
;
4677 if (type
== NULL_TREE
)
4680 push_obstacks (TYPE_OBSTACK (itype
), TYPE_OBSTACK (itype
));
4681 TYPE_MIN_VALUE (itype
) = convert (type
, lowval
);
4682 TYPE_MAX_VALUE (itype
) = highval
? convert (type
, highval
) : NULL
;
4685 TYPE_PRECISION (itype
) = TYPE_PRECISION (type
);
4686 TYPE_MODE (itype
) = TYPE_MODE (type
);
4687 TYPE_SIZE (itype
) = TYPE_SIZE (type
);
4688 TYPE_SIZE_UNIT (itype
) = TYPE_SIZE_UNIT (type
);
4689 TYPE_ALIGN (itype
) = TYPE_ALIGN (type
);
4691 if (host_integerp (lowval
, 0) && highval
!= 0 && host_integerp (highval
, 0))
4692 return type_hash_canon (tree_low_cst (highval
, 0)
4693 - tree_low_cst (lowval
, 0),
4699 /* Just like build_index_type, but takes lowval and highval instead
4700 of just highval (maxval). */
4703 build_index_2_type (lowval
,highval
)
4704 tree lowval
, highval
;
4706 return build_range_type (sizetype
, lowval
, highval
);
4709 /* Return nonzero iff ITYPE1 and ITYPE2 are equal (in the LISP sense).
4710 Needed because when index types are not hashed, equal index types
4711 built at different times appear distinct, even though structurally,
4715 index_type_equal (itype1
, itype2
)
4716 tree itype1
, itype2
;
4718 if (TREE_CODE (itype1
) != TREE_CODE (itype2
))
4721 if (TREE_CODE (itype1
) == INTEGER_TYPE
)
4723 if (TYPE_PRECISION (itype1
) != TYPE_PRECISION (itype2
)
4724 || TYPE_MODE (itype1
) != TYPE_MODE (itype2
)
4725 || simple_cst_equal (TYPE_SIZE (itype1
), TYPE_SIZE (itype2
)) != 1
4726 || TYPE_ALIGN (itype1
) != TYPE_ALIGN (itype2
))
4729 if (1 == simple_cst_equal (TYPE_MIN_VALUE (itype1
),
4730 TYPE_MIN_VALUE (itype2
))
4731 && 1 == simple_cst_equal (TYPE_MAX_VALUE (itype1
),
4732 TYPE_MAX_VALUE (itype2
)))
4739 /* Construct, lay out and return the type of arrays of elements with ELT_TYPE
4740 and number of elements specified by the range of values of INDEX_TYPE.
4741 If such a type has already been constructed, reuse it. */
4744 build_array_type (elt_type
, index_type
)
4745 tree elt_type
, index_type
;
4748 unsigned int hashcode
;
4750 if (TREE_CODE (elt_type
) == FUNCTION_TYPE
)
4752 error ("arrays of functions are not meaningful");
4753 elt_type
= integer_type_node
;
4756 /* Make sure TYPE_POINTER_TO (elt_type) is filled in. */
4757 build_pointer_type (elt_type
);
4759 /* Allocate the array after the pointer type,
4760 in case we free it in type_hash_canon. */
4761 t
= make_node (ARRAY_TYPE
);
4762 TREE_TYPE (t
) = elt_type
;
4763 TYPE_DOMAIN (t
) = index_type
;
4765 if (index_type
== 0)
4770 hashcode
= TYPE_HASH (elt_type
) + TYPE_HASH (index_type
);
4771 t
= type_hash_canon (hashcode
, t
);
4773 if (!COMPLETE_TYPE_P (t
))
4778 /* Return the TYPE of the elements comprising
4779 the innermost dimension of ARRAY. */
4782 get_inner_array_type (array
)
4785 tree type
= TREE_TYPE (array
);
4787 while (TREE_CODE (type
) == ARRAY_TYPE
)
4788 type
= TREE_TYPE (type
);
4793 /* Construct, lay out and return
4794 the type of functions returning type VALUE_TYPE
4795 given arguments of types ARG_TYPES.
4796 ARG_TYPES is a chain of TREE_LIST nodes whose TREE_VALUEs
4797 are data type nodes for the arguments of the function.
4798 If such a type has already been constructed, reuse it. */
4801 build_function_type (value_type
, arg_types
)
4802 tree value_type
, arg_types
;
4805 unsigned int hashcode
;
4807 if (TREE_CODE (value_type
) == FUNCTION_TYPE
)
4809 error ("function return type cannot be function");
4810 value_type
= integer_type_node
;
4813 /* Make a node of the sort we want. */
4814 t
= make_node (FUNCTION_TYPE
);
4815 TREE_TYPE (t
) = value_type
;
4816 TYPE_ARG_TYPES (t
) = arg_types
;
4818 /* If we already have such a type, use the old one and free this one. */
4819 hashcode
= TYPE_HASH (value_type
) + type_hash_list (arg_types
);
4820 t
= type_hash_canon (hashcode
, t
);
4822 if (!COMPLETE_TYPE_P (t
))
4827 /* Construct, lay out and return the type of methods belonging to class
4828 BASETYPE and whose arguments and values are described by TYPE.
4829 If that type exists already, reuse it.
4830 TYPE must be a FUNCTION_TYPE node. */
4833 build_method_type (basetype
, type
)
4834 tree basetype
, type
;
4837 unsigned int hashcode
;
4839 /* Make a node of the sort we want. */
4840 t
= make_node (METHOD_TYPE
);
4842 if (TREE_CODE (type
) != FUNCTION_TYPE
)
4845 TYPE_METHOD_BASETYPE (t
) = TYPE_MAIN_VARIANT (basetype
);
4846 TREE_TYPE (t
) = TREE_TYPE (type
);
4848 /* The actual arglist for this function includes a "hidden" argument
4849 which is "this". Put it into the list of argument types. */
4852 = tree_cons (NULL_TREE
,
4853 build_pointer_type (basetype
), TYPE_ARG_TYPES (type
));
4855 /* If we already have such a type, use the old one and free this one. */
4856 hashcode
= TYPE_HASH (basetype
) + TYPE_HASH (type
);
4857 t
= type_hash_canon (hashcode
, t
);
4859 if (!COMPLETE_TYPE_P (t
))
4865 /* Construct, lay out and return the type of offsets to a value
4866 of type TYPE, within an object of type BASETYPE.
4867 If a suitable offset type exists already, reuse it. */
4870 build_offset_type (basetype
, type
)
4871 tree basetype
, type
;
4874 unsigned int hashcode
;
4876 /* Make a node of the sort we want. */
4877 t
= make_node (OFFSET_TYPE
);
4879 TYPE_OFFSET_BASETYPE (t
) = TYPE_MAIN_VARIANT (basetype
);
4880 TREE_TYPE (t
) = type
;
4882 /* If we already have such a type, use the old one and free this one. */
4883 hashcode
= TYPE_HASH (basetype
) + TYPE_HASH (type
);
4884 t
= type_hash_canon (hashcode
, t
);
4886 if (!COMPLETE_TYPE_P (t
))
4892 /* Create a complex type whose components are COMPONENT_TYPE. */
4895 build_complex_type (component_type
)
4896 tree component_type
;
4899 unsigned int hashcode
;
4901 /* Make a node of the sort we want. */
4902 t
= make_node (COMPLEX_TYPE
);
4904 TREE_TYPE (t
) = TYPE_MAIN_VARIANT (component_type
);
4905 set_type_quals (t
, TYPE_QUALS (component_type
));
4907 /* If we already have such a type, use the old one and free this one. */
4908 hashcode
= TYPE_HASH (component_type
);
4909 t
= type_hash_canon (hashcode
, t
);
4911 if (!COMPLETE_TYPE_P (t
))
4914 /* If we are writing Dwarf2 output we need to create a name,
4915 since complex is a fundamental type. */
4916 if (write_symbols
== DWARF2_DEBUG
&& ! TYPE_NAME (t
))
4919 if (component_type
== char_type_node
)
4920 name
= "complex char";
4921 else if (component_type
== signed_char_type_node
)
4922 name
= "complex signed char";
4923 else if (component_type
== unsigned_char_type_node
)
4924 name
= "complex unsigned char";
4925 else if (component_type
== short_integer_type_node
)
4926 name
= "complex short int";
4927 else if (component_type
== short_unsigned_type_node
)
4928 name
= "complex short unsigned int";
4929 else if (component_type
== integer_type_node
)
4930 name
= "complex int";
4931 else if (component_type
== unsigned_type_node
)
4932 name
= "complex unsigned int";
4933 else if (component_type
== long_integer_type_node
)
4934 name
= "complex long int";
4935 else if (component_type
== long_unsigned_type_node
)
4936 name
= "complex long unsigned int";
4937 else if (component_type
== long_long_integer_type_node
)
4938 name
= "complex long long int";
4939 else if (component_type
== long_long_unsigned_type_node
)
4940 name
= "complex long long unsigned int";
4945 TYPE_NAME (t
) = get_identifier (name
);
4951 /* Return OP, stripped of any conversions to wider types as much as is safe.
4952 Converting the value back to OP's type makes a value equivalent to OP.
4954 If FOR_TYPE is nonzero, we return a value which, if converted to
4955 type FOR_TYPE, would be equivalent to converting OP to type FOR_TYPE.
4957 If FOR_TYPE is nonzero, unaligned bit-field references may be changed to the
4958 narrowest type that can hold the value, even if they don't exactly fit.
4959 Otherwise, bit-field references are changed to a narrower type
4960 only if they can be fetched directly from memory in that type.
4962 OP must have integer, real or enumeral type. Pointers are not allowed!
4964 There are some cases where the obvious value we could return
4965 would regenerate to OP if converted to OP's type,
4966 but would not extend like OP to wider types.
4967 If FOR_TYPE indicates such extension is contemplated, we eschew such values.
4968 For example, if OP is (unsigned short)(signed char)-1,
4969 we avoid returning (signed char)-1 if FOR_TYPE is int,
4970 even though extending that to an unsigned short would regenerate OP,
4971 since the result of extending (signed char)-1 to (int)
4972 is different from (int) OP. */
4975 get_unwidened (op
, for_type
)
4979 /* Set UNS initially if converting OP to FOR_TYPE is a zero-extension. */
4980 register tree type
= TREE_TYPE (op
);
4981 register unsigned final_prec
4982 = TYPE_PRECISION (for_type
!= 0 ? for_type
: type
);
4984 = (for_type
!= 0 && for_type
!= type
4985 && final_prec
> TYPE_PRECISION (type
)
4986 && TREE_UNSIGNED (type
));
4987 register tree win
= op
;
4989 while (TREE_CODE (op
) == NOP_EXPR
)
4991 register int bitschange
4992 = TYPE_PRECISION (TREE_TYPE (op
))
4993 - TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (op
, 0)));
4995 /* Truncations are many-one so cannot be removed.
4996 Unless we are later going to truncate down even farther. */
4998 && final_prec
> TYPE_PRECISION (TREE_TYPE (op
)))
5001 /* See what's inside this conversion. If we decide to strip it,
5003 op
= TREE_OPERAND (op
, 0);
5005 /* If we have not stripped any zero-extensions (uns is 0),
5006 we can strip any kind of extension.
5007 If we have previously stripped a zero-extension,
5008 only zero-extensions can safely be stripped.
5009 Any extension can be stripped if the bits it would produce
5010 are all going to be discarded later by truncating to FOR_TYPE. */
5014 if (! uns
|| final_prec
<= TYPE_PRECISION (TREE_TYPE (op
)))
5016 /* TREE_UNSIGNED says whether this is a zero-extension.
5017 Let's avoid computing it if it does not affect WIN
5018 and if UNS will not be needed again. */
5019 if ((uns
|| TREE_CODE (op
) == NOP_EXPR
)
5020 && TREE_UNSIGNED (TREE_TYPE (op
)))
5028 if (TREE_CODE (op
) == COMPONENT_REF
5029 /* Since type_for_size always gives an integer type. */
5030 && TREE_CODE (type
) != REAL_TYPE
5031 /* Don't crash if field not laid out yet. */
5032 && DECL_SIZE (TREE_OPERAND (op
, 1)) != 0)
5034 unsigned int innerprec
5035 = TREE_INT_CST_LOW (DECL_SIZE (TREE_OPERAND (op
, 1)));
5037 type
= type_for_size (innerprec
, TREE_UNSIGNED (TREE_OPERAND (op
, 1)));
5039 /* We can get this structure field in the narrowest type it fits in.
5040 If FOR_TYPE is 0, do this only for a field that matches the
5041 narrower type exactly and is aligned for it
5042 The resulting extension to its nominal type (a fullword type)
5043 must fit the same conditions as for other extensions. */
5045 if (innerprec
< TYPE_PRECISION (TREE_TYPE (op
))
5046 && (for_type
|| ! DECL_BIT_FIELD (TREE_OPERAND (op
, 1)))
5047 && (! uns
|| final_prec
<= innerprec
5048 || TREE_UNSIGNED (TREE_OPERAND (op
, 1)))
5051 win
= build (COMPONENT_REF
, type
, TREE_OPERAND (op
, 0),
5052 TREE_OPERAND (op
, 1));
5053 TREE_SIDE_EFFECTS (win
) = TREE_SIDE_EFFECTS (op
);
5054 TREE_THIS_VOLATILE (win
) = TREE_THIS_VOLATILE (op
);
5060 /* Return OP or a simpler expression for a narrower value
5061 which can be sign-extended or zero-extended to give back OP.
5062 Store in *UNSIGNEDP_PTR either 1 if the value should be zero-extended
5063 or 0 if the value should be sign-extended. */
5066 get_narrower (op
, unsignedp_ptr
)
5070 register int uns
= 0;
5072 register tree win
= op
;
5074 while (TREE_CODE (op
) == NOP_EXPR
)
5076 register int bitschange
5077 = (TYPE_PRECISION (TREE_TYPE (op
))
5078 - TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (op
, 0))));
5080 /* Truncations are many-one so cannot be removed. */
5084 /* See what's inside this conversion. If we decide to strip it,
5086 op
= TREE_OPERAND (op
, 0);
5090 /* An extension: the outermost one can be stripped,
5091 but remember whether it is zero or sign extension. */
5093 uns
= TREE_UNSIGNED (TREE_TYPE (op
));
5094 /* Otherwise, if a sign extension has been stripped,
5095 only sign extensions can now be stripped;
5096 if a zero extension has been stripped, only zero-extensions. */
5097 else if (uns
!= TREE_UNSIGNED (TREE_TYPE (op
)))
5101 else /* bitschange == 0 */
5103 /* A change in nominal type can always be stripped, but we must
5104 preserve the unsignedness. */
5106 uns
= TREE_UNSIGNED (TREE_TYPE (op
));
5113 if (TREE_CODE (op
) == COMPONENT_REF
5114 /* Since type_for_size always gives an integer type. */
5115 && TREE_CODE (TREE_TYPE (op
)) != REAL_TYPE
)
5117 unsigned int innerprec
5118 = TREE_INT_CST_LOW (DECL_SIZE (TREE_OPERAND (op
, 1)));
5120 tree type
= type_for_size (innerprec
, TREE_UNSIGNED (op
));
5122 /* We can get this structure field in a narrower type that fits it,
5123 but the resulting extension to its nominal type (a fullword type)
5124 must satisfy the same conditions as for other extensions.
5126 Do this only for fields that are aligned (not bit-fields),
5127 because when bit-field insns will be used there is no
5128 advantage in doing this. */
5130 if (innerprec
< TYPE_PRECISION (TREE_TYPE (op
))
5131 && ! DECL_BIT_FIELD (TREE_OPERAND (op
, 1))
5132 && (first
|| uns
== TREE_UNSIGNED (TREE_OPERAND (op
, 1)))
5136 uns
= TREE_UNSIGNED (TREE_OPERAND (op
, 1));
5137 win
= build (COMPONENT_REF
, type
, TREE_OPERAND (op
, 0),
5138 TREE_OPERAND (op
, 1));
5139 TREE_SIDE_EFFECTS (win
) = TREE_SIDE_EFFECTS (op
);
5140 TREE_THIS_VOLATILE (win
) = TREE_THIS_VOLATILE (op
);
5143 *unsignedp_ptr
= uns
;
5147 /* Nonzero if integer constant C has a value that is permissible
5148 for type TYPE (an INTEGER_TYPE). */
5151 int_fits_type_p (c
, type
)
5154 if (TREE_UNSIGNED (type
))
5155 return (! (TREE_CODE (TYPE_MAX_VALUE (type
)) == INTEGER_CST
5156 && INT_CST_LT_UNSIGNED (TYPE_MAX_VALUE (type
), c
))
5157 && ! (TREE_CODE (TYPE_MIN_VALUE (type
)) == INTEGER_CST
5158 && INT_CST_LT_UNSIGNED (c
, TYPE_MIN_VALUE (type
)))
5159 /* Negative ints never fit unsigned types. */
5160 && ! (TREE_INT_CST_HIGH (c
) < 0
5161 && ! TREE_UNSIGNED (TREE_TYPE (c
))));
5163 return (! (TREE_CODE (TYPE_MAX_VALUE (type
)) == INTEGER_CST
5164 && INT_CST_LT (TYPE_MAX_VALUE (type
), c
))
5165 && ! (TREE_CODE (TYPE_MIN_VALUE (type
)) == INTEGER_CST
5166 && INT_CST_LT (c
, TYPE_MIN_VALUE (type
)))
5167 /* Unsigned ints with top bit set never fit signed types. */
5168 && ! (TREE_INT_CST_HIGH (c
) < 0
5169 && TREE_UNSIGNED (TREE_TYPE (c
))));
5172 /* Given a DECL or TYPE, return the scope in which it was declared, or
5173 NULL_TREE if there is no containing scope. */
5176 get_containing_scope (t
)
5179 return (TYPE_P (t
) ? TYPE_CONTEXT (t
) : DECL_CONTEXT (t
));
5182 /* Return the innermost context enclosing DECL that is
5183 a FUNCTION_DECL, or zero if none. */
5186 decl_function_context (decl
)
5191 if (TREE_CODE (decl
) == ERROR_MARK
)
5194 if (TREE_CODE (decl
) == SAVE_EXPR
)
5195 context
= SAVE_EXPR_CONTEXT (decl
);
5197 /* C++ virtual functions use DECL_CONTEXT for the class of the vtable
5198 where we look up the function at runtime. Such functions always take
5199 a first argument of type 'pointer to real context'.
5201 C++ should really be fixed to use DECL_CONTEXT for the real context,
5202 and use something else for the "virtual context". */
5203 else if (TREE_CODE (decl
) == FUNCTION_DECL
&& DECL_VINDEX (decl
))
5206 (TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (TREE_TYPE (decl
)))));
5208 context
= DECL_CONTEXT (decl
);
5210 while (context
&& TREE_CODE (context
) != FUNCTION_DECL
)
5212 if (TREE_CODE (context
) == BLOCK
)
5213 context
= BLOCK_SUPERCONTEXT (context
);
5215 context
= get_containing_scope (context
);
5221 /* Return the innermost context enclosing DECL that is
5222 a RECORD_TYPE, UNION_TYPE or QUAL_UNION_TYPE, or zero if none.
5223 TYPE_DECLs and FUNCTION_DECLs are transparent to this function. */
5226 decl_type_context (decl
)
5229 tree context
= DECL_CONTEXT (decl
);
5233 if (TREE_CODE (context
) == RECORD_TYPE
5234 || TREE_CODE (context
) == UNION_TYPE
5235 || TREE_CODE (context
) == QUAL_UNION_TYPE
)
5238 if (TREE_CODE (context
) == TYPE_DECL
5239 || TREE_CODE (context
) == FUNCTION_DECL
)
5240 context
= DECL_CONTEXT (context
);
5242 else if (TREE_CODE (context
) == BLOCK
)
5243 context
= BLOCK_SUPERCONTEXT (context
);
5246 /* Unhandled CONTEXT!? */
5252 /* CALL is a CALL_EXPR. Return the declaration for the function
5253 called, or NULL_TREE if the called function cannot be
5257 get_callee_fndecl (call
)
5262 /* It's invalid to call this function with anything but a
5264 if (TREE_CODE (call
) != CALL_EXPR
)
5267 /* The first operand to the CALL is the address of the function
5269 addr
= TREE_OPERAND (call
, 0);
5273 /* If this is a readonly function pointer, extract its initial value. */
5274 if (DECL_P (addr
) && TREE_CODE (addr
) != FUNCTION_DECL
5275 && TREE_READONLY (addr
) && ! TREE_THIS_VOLATILE (addr
)
5276 && DECL_INITIAL (addr
))
5277 addr
= DECL_INITIAL (addr
);
5279 /* If the address is just `&f' for some function `f', then we know
5280 that `f' is being called. */
5281 if (TREE_CODE (addr
) == ADDR_EXPR
5282 && TREE_CODE (TREE_OPERAND (addr
, 0)) == FUNCTION_DECL
)
5283 return TREE_OPERAND (addr
, 0);
5285 /* We couldn't figure out what was being called. */
5289 /* Print debugging information about the obstack O, named STR. */
5292 print_obstack_statistics (str
, o
)
5296 struct _obstack_chunk
*chunk
= o
->chunk
;
5300 n_alloc
+= o
->next_free
- chunk
->contents
;
5301 chunk
= chunk
->prev
;
5305 n_alloc
+= chunk
->limit
- &chunk
->contents
[0];
5306 chunk
= chunk
->prev
;
5308 fprintf (stderr
, "obstack %s: %u bytes, %d chunks\n",
5309 str
, n_alloc
, n_chunks
);
5312 /* Print debugging information about tree nodes generated during the compile,
5313 and any language-specific information. */
5316 dump_tree_statistics ()
5318 #ifdef GATHER_STATISTICS
5320 int total_nodes
, total_bytes
;
5323 fprintf (stderr
, "\n??? tree nodes created\n\n");
5324 #ifdef GATHER_STATISTICS
5325 fprintf (stderr
, "Kind Nodes Bytes\n");
5326 fprintf (stderr
, "-------------------------------------\n");
5327 total_nodes
= total_bytes
= 0;
5328 for (i
= 0; i
< (int) all_kinds
; i
++)
5330 fprintf (stderr
, "%-20s %6d %9d\n", tree_node_kind_names
[i
],
5331 tree_node_counts
[i
], tree_node_sizes
[i
]);
5332 total_nodes
+= tree_node_counts
[i
];
5333 total_bytes
+= tree_node_sizes
[i
];
5335 fprintf (stderr
, "%-20s %9d\n", "identifier names", id_string_size
);
5336 fprintf (stderr
, "-------------------------------------\n");
5337 fprintf (stderr
, "%-20s %6d %9d\n", "Total", total_nodes
, total_bytes
);
5338 fprintf (stderr
, "-------------------------------------\n");
5340 fprintf (stderr
, "(No per-node statistics)\n");
5342 print_obstack_statistics ("permanent_obstack", &permanent_obstack
);
5343 print_obstack_statistics ("maybepermanent_obstack", &maybepermanent_obstack
);
5344 print_obstack_statistics ("temporary_obstack", &temporary_obstack
);
5345 print_obstack_statistics ("momentary_obstack", &momentary_obstack
);
5346 print_obstack_statistics ("temp_decl_obstack", &temp_decl_obstack
);
5347 print_type_hash_statistics ();
5348 print_lang_statistics ();
5351 #define FILE_FUNCTION_PREFIX_LEN 9
5353 #ifndef NO_DOLLAR_IN_LABEL
5354 #define FILE_FUNCTION_FORMAT "_GLOBAL_$%s$%s"
5355 #else /* NO_DOLLAR_IN_LABEL */
5356 #ifndef NO_DOT_IN_LABEL
5357 #define FILE_FUNCTION_FORMAT "_GLOBAL_.%s.%s"
5358 #else /* NO_DOT_IN_LABEL */
5359 #define FILE_FUNCTION_FORMAT "_GLOBAL__%s_%s"
5360 #endif /* NO_DOT_IN_LABEL */
5361 #endif /* NO_DOLLAR_IN_LABEL */
5363 /* Appends 6 random characters to TEMPLATE to (hopefully) avoid name
5364 clashes in cases where we can't reliably choose a unique name.
5366 Derived from mkstemp.c in libiberty. */
5369 append_random_chars (template)
5372 static const char letters
[]
5373 = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789";
5374 static unsigned HOST_WIDE_INT value
;
5375 unsigned HOST_WIDE_INT v
;
5377 #ifdef HAVE_GETTIMEOFDAY
5381 template += strlen (template);
5383 #ifdef HAVE_GETTIMEOFDAY
5384 /* Get some more or less random data. */
5385 gettimeofday (&tv
, NULL
);
5386 value
+= ((unsigned HOST_WIDE_INT
) tv
.tv_usec
<< 16) ^ tv
.tv_sec
^ getpid ();
5393 /* Fill in the random bits. */
5394 template[0] = letters
[v
% 62];
5396 template[1] = letters
[v
% 62];
5398 template[2] = letters
[v
% 62];
5400 template[3] = letters
[v
% 62];
5402 template[4] = letters
[v
% 62];
5404 template[5] = letters
[v
% 62];
5409 /* Generate a name for a function unique to this translation unit.
5410 TYPE is some string to identify the purpose of this function to the
5411 linker or collect2. */
5414 get_file_function_name_long (type
)
5421 if (first_global_object_name
)
5422 p
= first_global_object_name
;
5425 /* We don't have anything that we know to be unique to this translation
5426 unit, so use what we do have and throw in some randomness. */
5428 const char *name
= weak_global_object_name
;
5429 const char *file
= main_input_filename
;
5434 file
= input_filename
;
5436 q
= (char *) alloca (7 + strlen (name
) + strlen (file
));
5438 sprintf (q
, "%s%s", name
, file
);
5439 append_random_chars (q
);
5443 buf
= (char *) alloca (sizeof (FILE_FUNCTION_FORMAT
) + strlen (p
)
5446 /* Set up the name of the file-level functions we may need.
5447 Use a global object (which is already required to be unique over
5448 the program) rather than the file name (which imposes extra
5450 sprintf (buf
, FILE_FUNCTION_FORMAT
, type
, p
);
5452 /* Don't need to pull weird characters out of global names. */
5453 if (p
!= first_global_object_name
)
5455 for (q
= buf
+11; *q
; q
++)
5457 #ifndef NO_DOLLAR_IN_LABEL /* this for `$'; unlikely, but... -- kr */
5460 #ifndef NO_DOT_IN_LABEL /* this for `.'; unlikely, but... */
5468 return get_identifier (buf
);
5471 /* If KIND=='I', return a suitable global initializer (constructor) name.
5472 If KIND=='D', return a suitable global clean-up (destructor) name. */
5475 get_file_function_name (kind
)
5483 return get_file_function_name_long (p
);
5486 /* Expand (the constant part of) a SET_TYPE CONSTRUCTOR node.
5487 The result is placed in BUFFER (which has length BIT_SIZE),
5488 with one bit in each char ('\000' or '\001').
5490 If the constructor is constant, NULL_TREE is returned.
5491 Otherwise, a TREE_LIST of the non-constant elements is emitted. */
5494 get_set_constructor_bits (init
, buffer
, bit_size
)
5501 HOST_WIDE_INT domain_min
5502 = TREE_INT_CST_LOW (TYPE_MIN_VALUE (TYPE_DOMAIN (TREE_TYPE (init
))));
5503 tree non_const_bits
= NULL_TREE
;
5504 for (i
= 0; i
< bit_size
; i
++)
5507 for (vals
= TREE_OPERAND (init
, 1);
5508 vals
!= NULL_TREE
; vals
= TREE_CHAIN (vals
))
5510 if (TREE_CODE (TREE_VALUE (vals
)) != INTEGER_CST
5511 || (TREE_PURPOSE (vals
) != NULL_TREE
5512 && TREE_CODE (TREE_PURPOSE (vals
)) != INTEGER_CST
))
5514 = tree_cons (TREE_PURPOSE (vals
), TREE_VALUE (vals
), non_const_bits
);
5515 else if (TREE_PURPOSE (vals
) != NULL_TREE
)
5517 /* Set a range of bits to ones. */
5518 HOST_WIDE_INT lo_index
5519 = TREE_INT_CST_LOW (TREE_PURPOSE (vals
)) - domain_min
;
5520 HOST_WIDE_INT hi_index
5521 = TREE_INT_CST_LOW (TREE_VALUE (vals
)) - domain_min
;
5523 if (lo_index
< 0 || lo_index
>= bit_size
5524 || hi_index
< 0 || hi_index
>= bit_size
)
5526 for ( ; lo_index
<= hi_index
; lo_index
++)
5527 buffer
[lo_index
] = 1;
5531 /* Set a single bit to one. */
5533 = TREE_INT_CST_LOW (TREE_VALUE (vals
)) - domain_min
;
5534 if (index
< 0 || index
>= bit_size
)
5536 error ("invalid initializer for bit string");
5542 return non_const_bits
;
5545 /* Expand (the constant part of) a SET_TYPE CONSTRUCTOR node.
5546 The result is placed in BUFFER (which is an array of bytes).
5547 If the constructor is constant, NULL_TREE is returned.
5548 Otherwise, a TREE_LIST of the non-constant elements is emitted. */
5551 get_set_constructor_bytes (init
, buffer
, wd_size
)
5553 unsigned char *buffer
;
5557 int set_word_size
= BITS_PER_UNIT
;
5558 int bit_size
= wd_size
* set_word_size
;
5560 unsigned char *bytep
= buffer
;
5561 char *bit_buffer
= (char *) alloca(bit_size
);
5562 tree non_const_bits
= get_set_constructor_bits (init
, bit_buffer
, bit_size
);
5564 for (i
= 0; i
< wd_size
; i
++)
5567 for (i
= 0; i
< bit_size
; i
++)
5571 if (BYTES_BIG_ENDIAN
)
5572 *bytep
|= (1 << (set_word_size
- 1 - bit_pos
));
5574 *bytep
|= 1 << bit_pos
;
5577 if (bit_pos
>= set_word_size
)
5578 bit_pos
= 0, bytep
++;
5580 return non_const_bits
;
5583 #if defined ENABLE_TREE_CHECKING && (GCC_VERSION >= 2007)
5584 /* Complain that the tree code of NODE does not match the expected CODE.
5585 FILE, LINE, and FUNCTION are of the caller. */
5587 tree_check_failed (node
, code
, file
, line
, function
)
5589 enum tree_code code
;
5592 const char *function
;
5594 error ("Tree check: expected %s, have %s",
5595 tree_code_name
[code
], tree_code_name
[TREE_CODE (node
)]);
5596 fancy_abort (file
, line
, function
);
5599 /* Similar to above, except that we check for a class of tree
5600 code, given in CL. */
5602 tree_class_check_failed (node
, cl
, file
, line
, function
)
5607 const char *function
;
5609 error ("Tree check: expected class '%c', have '%c' (%s)",
5610 cl
, TREE_CODE_CLASS (TREE_CODE (node
)),
5611 tree_code_name
[TREE_CODE (node
)]);
5612 fancy_abort (file
, line
, function
);
5615 #endif /* ENABLE_TREE_CHECKING */
5617 /* Return the alias set for T, which may be either a type or an
5624 if (! flag_strict_aliasing
|| lang_get_alias_set
== 0)
5625 /* If we're not doing any lanaguage-specific alias analysis, just
5626 assume everything aliases everything else. */
5629 return (*lang_get_alias_set
) (t
);
5632 /* Return a brand-new alias set. */
5637 static int last_alias_set
;
5639 if (flag_strict_aliasing
)
5640 return ++last_alias_set
;
5645 #ifndef CHAR_TYPE_SIZE
5646 #define CHAR_TYPE_SIZE BITS_PER_UNIT
5649 #ifndef SHORT_TYPE_SIZE
5650 #define SHORT_TYPE_SIZE (BITS_PER_UNIT * MIN ((UNITS_PER_WORD + 1) / 2, 2))
5653 #ifndef INT_TYPE_SIZE
5654 #define INT_TYPE_SIZE BITS_PER_WORD
5657 #ifndef LONG_TYPE_SIZE
5658 #define LONG_TYPE_SIZE BITS_PER_WORD
5661 #ifndef LONG_LONG_TYPE_SIZE
5662 #define LONG_LONG_TYPE_SIZE (BITS_PER_WORD * 2)
5665 #ifndef FLOAT_TYPE_SIZE
5666 #define FLOAT_TYPE_SIZE BITS_PER_WORD
5669 #ifndef DOUBLE_TYPE_SIZE
5670 #define DOUBLE_TYPE_SIZE (BITS_PER_WORD * 2)
5673 #ifndef LONG_DOUBLE_TYPE_SIZE
5674 #define LONG_DOUBLE_TYPE_SIZE (BITS_PER_WORD * 2)
5677 /* Create nodes for all integer types (and error_mark_node) using the sizes
5678 of C datatypes. The caller should call set_sizetype soon after calling
5679 this function to select one of the types as sizetype. */
5682 build_common_tree_nodes (signed_char
)
5685 error_mark_node
= make_node (ERROR_MARK
);
5686 TREE_TYPE (error_mark_node
) = error_mark_node
;
5688 initialize_sizetypes ();
5690 /* Define both `signed char' and `unsigned char'. */
5691 signed_char_type_node
= make_signed_type (CHAR_TYPE_SIZE
);
5692 unsigned_char_type_node
= make_unsigned_type (CHAR_TYPE_SIZE
);
5694 /* Define `char', which is like either `signed char' or `unsigned char'
5695 but not the same as either. */
5698 ? make_signed_type (CHAR_TYPE_SIZE
)
5699 : make_unsigned_type (CHAR_TYPE_SIZE
));
5701 short_integer_type_node
= make_signed_type (SHORT_TYPE_SIZE
);
5702 short_unsigned_type_node
= make_unsigned_type (SHORT_TYPE_SIZE
);
5703 integer_type_node
= make_signed_type (INT_TYPE_SIZE
);
5704 unsigned_type_node
= make_unsigned_type (INT_TYPE_SIZE
);
5705 long_integer_type_node
= make_signed_type (LONG_TYPE_SIZE
);
5706 long_unsigned_type_node
= make_unsigned_type (LONG_TYPE_SIZE
);
5707 long_long_integer_type_node
= make_signed_type (LONG_LONG_TYPE_SIZE
);
5708 long_long_unsigned_type_node
= make_unsigned_type (LONG_LONG_TYPE_SIZE
);
5710 intQI_type_node
= make_signed_type (GET_MODE_BITSIZE (QImode
));
5711 intHI_type_node
= make_signed_type (GET_MODE_BITSIZE (HImode
));
5712 intSI_type_node
= make_signed_type (GET_MODE_BITSIZE (SImode
));
5713 intDI_type_node
= make_signed_type (GET_MODE_BITSIZE (DImode
));
5714 #if HOST_BITS_PER_WIDE_INT >= 64
5715 intTI_type_node
= make_signed_type (GET_MODE_BITSIZE (TImode
));
5718 unsigned_intQI_type_node
= make_unsigned_type (GET_MODE_BITSIZE (QImode
));
5719 unsigned_intHI_type_node
= make_unsigned_type (GET_MODE_BITSIZE (HImode
));
5720 unsigned_intSI_type_node
= make_unsigned_type (GET_MODE_BITSIZE (SImode
));
5721 unsigned_intDI_type_node
= make_unsigned_type (GET_MODE_BITSIZE (DImode
));
5722 #if HOST_BITS_PER_WIDE_INT >= 64
5723 unsigned_intTI_type_node
= make_unsigned_type (GET_MODE_BITSIZE (TImode
));
5727 /* Call this function after calling build_common_tree_nodes and set_sizetype.
5728 It will create several other common tree nodes. */
5731 build_common_tree_nodes_2 (short_double
)
5734 /* Define these next since types below may used them. */
5735 integer_zero_node
= build_int_2 (0, 0);
5736 integer_one_node
= build_int_2 (1, 0);
5738 size_zero_node
= size_int (0);
5739 size_one_node
= size_int (1);
5740 bitsize_zero_node
= bitsize_int (0);
5741 bitsize_one_node
= bitsize_int (1);
5742 bitsize_unit_node
= bitsize_int (BITS_PER_UNIT
);
5744 void_type_node
= make_node (VOID_TYPE
);
5745 layout_type (void_type_node
);
5747 /* We are not going to have real types in C with less than byte alignment,
5748 so we might as well not have any types that claim to have it. */
5749 TYPE_ALIGN (void_type_node
) = BITS_PER_UNIT
;
5751 null_pointer_node
= build_int_2 (0, 0);
5752 TREE_TYPE (null_pointer_node
) = build_pointer_type (void_type_node
);
5753 layout_type (TREE_TYPE (null_pointer_node
));
5755 ptr_type_node
= build_pointer_type (void_type_node
);
5757 = build_pointer_type (build_type_variant (void_type_node
, 1, 0));
5759 float_type_node
= make_node (REAL_TYPE
);
5760 TYPE_PRECISION (float_type_node
) = FLOAT_TYPE_SIZE
;
5761 layout_type (float_type_node
);
5763 double_type_node
= make_node (REAL_TYPE
);
5765 TYPE_PRECISION (double_type_node
) = FLOAT_TYPE_SIZE
;
5767 TYPE_PRECISION (double_type_node
) = DOUBLE_TYPE_SIZE
;
5768 layout_type (double_type_node
);
5770 long_double_type_node
= make_node (REAL_TYPE
);
5771 TYPE_PRECISION (long_double_type_node
) = LONG_DOUBLE_TYPE_SIZE
;
5772 layout_type (long_double_type_node
);
5774 complex_integer_type_node
= make_node (COMPLEX_TYPE
);
5775 TREE_TYPE (complex_integer_type_node
) = integer_type_node
;
5776 layout_type (complex_integer_type_node
);
5778 complex_float_type_node
= make_node (COMPLEX_TYPE
);
5779 TREE_TYPE (complex_float_type_node
) = float_type_node
;
5780 layout_type (complex_float_type_node
);
5782 complex_double_type_node
= make_node (COMPLEX_TYPE
);
5783 TREE_TYPE (complex_double_type_node
) = double_type_node
;
5784 layout_type (complex_double_type_node
);
5786 complex_long_double_type_node
= make_node (COMPLEX_TYPE
);
5787 TREE_TYPE (complex_long_double_type_node
) = long_double_type_node
;
5788 layout_type (complex_long_double_type_node
);
5790 #ifdef BUILD_VA_LIST_TYPE
5791 BUILD_VA_LIST_TYPE(va_list_type_node
);
5793 va_list_type_node
= ptr_type_node
;