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. */
48 #define obstack_chunk_alloc xmalloc
49 #define obstack_chunk_free free
50 /* obstack.[ch] explicitly declined to prototype this. */
51 extern int _obstack_allocated_p
PARAMS ((struct obstack
*h
, PTR obj
));
53 static void unsave_expr_now_r
PARAMS ((tree
));
55 /* Tree nodes of permanent duration are allocated in this obstack.
56 They are the identifier nodes, and everything outside of
57 the bodies and parameters of function definitions. */
59 struct obstack permanent_obstack
;
61 /* The initial RTL, and all ..._TYPE nodes, in a function
62 are allocated in this obstack. Usually they are freed at the
63 end of the function, but if the function is inline they are saved.
64 For top-level functions, this is maybepermanent_obstack.
65 Separate obstacks are made for nested functions. */
67 struct obstack
*function_maybepermanent_obstack
;
69 /* This is the function_maybepermanent_obstack for top-level functions. */
71 struct obstack maybepermanent_obstack
;
73 /* The contents of the current function definition are allocated
74 in this obstack, and all are freed at the end of the function.
75 For top-level functions, this is temporary_obstack.
76 Separate obstacks are made for nested functions. */
78 struct obstack
*function_obstack
;
80 /* This is used for reading initializers of global variables. */
82 struct obstack temporary_obstack
;
84 /* The tree nodes of an expression are allocated
85 in this obstack, and all are freed at the end of the expression. */
87 struct obstack momentary_obstack
;
89 /* The tree nodes of a declarator are allocated
90 in this obstack, and all are freed when the declarator
93 static struct obstack temp_decl_obstack
;
95 /* This points at either permanent_obstack
96 or the current function_maybepermanent_obstack. */
98 struct obstack
*saveable_obstack
;
100 /* This is same as saveable_obstack during parse and expansion phase;
101 it points to the current function's obstack during optimization.
102 This is the obstack to be used for creating rtl objects. */
104 struct obstack
*rtl_obstack
;
106 /* This points at either permanent_obstack or the current function_obstack. */
108 struct obstack
*current_obstack
;
110 /* This points at either permanent_obstack or the current function_obstack
111 or momentary_obstack. */
113 struct obstack
*expression_obstack
;
115 /* Stack of obstack selections for push_obstacks and pop_obstacks. */
119 struct obstack_stack
*next
;
120 struct obstack
*current
;
121 struct obstack
*saveable
;
122 struct obstack
*expression
;
126 struct obstack_stack
*obstack_stack
;
128 /* Obstack for allocating struct obstack_stack entries. */
130 static struct obstack obstack_stack_obstack
;
132 /* Addresses of first objects in some obstacks.
133 This is for freeing their entire contents. */
134 char *maybepermanent_firstobj
;
135 char *temporary_firstobj
;
136 char *momentary_firstobj
;
137 char *temp_decl_firstobj
;
139 /* This is used to preserve objects (mainly array initializers) that need to
140 live until the end of the current function, but no further. */
141 char *momentary_function_firstobj
;
143 /* Nonzero means all ..._TYPE nodes should be allocated permanently. */
145 int all_types_permanent
;
147 /* Stack of places to restore the momentary obstack back to. */
149 struct momentary_level
151 /* Pointer back to previous such level. */
152 struct momentary_level
*prev
;
153 /* First object allocated within this level. */
155 /* Value of expression_obstack saved at entry to this level. */
156 struct obstack
*obstack
;
159 struct momentary_level
*momentary_stack
;
161 /* Table indexed by tree code giving a string containing a character
162 classifying the tree code. Possibilities are
163 t, d, s, c, r, <, 1, 2 and e. See tree.def for details. */
165 #define DEFTREECODE(SYM, NAME, TYPE, LENGTH) TYPE,
167 char tree_code_type
[MAX_TREE_CODES
] = {
172 /* Table indexed by tree code giving number of expression
173 operands beyond the fixed part of the node structure.
174 Not used for types or decls. */
176 #define DEFTREECODE(SYM, NAME, TYPE, LENGTH) LENGTH,
178 int tree_code_length
[MAX_TREE_CODES
] = {
183 /* Names of tree components.
184 Used for printing out the tree and error messages. */
185 #define DEFTREECODE(SYM, NAME, TYPE, LEN) NAME,
187 const char *tree_code_name
[MAX_TREE_CODES
] = {
192 /* Statistics-gathering stuff. */
213 int tree_node_counts
[(int)all_kinds
];
214 int tree_node_sizes
[(int)all_kinds
];
215 int id_string_size
= 0;
217 static const char * const tree_node_kind_names
[] = {
235 /* Hash table for uniquizing IDENTIFIER_NODEs by name. */
237 #define MAX_HASH_TABLE 1009
238 static tree hash_table
[MAX_HASH_TABLE
]; /* id hash buckets */
240 /* 0 while creating built-in identifiers. */
241 static int do_identifier_warnings
;
243 /* Unique id for next decl created. */
244 static int next_decl_uid
;
245 /* Unique id for next type created. */
246 static int next_type_uid
= 1;
248 /* The language-specific function for alias analysis. If NULL, the
249 language does not do any special alias analysis. */
250 int (*lang_get_alias_set
) PARAMS ((tree
));
252 /* Here is how primitive or already-canonicalized types' hash
254 #define TYPE_HASH(TYPE) ((unsigned long) (TYPE) & 0777777)
256 /* Since we cannot rehash a type after it is in the table, we have to
257 keep the hash code. */
265 /* Initial size of the hash table (rounded to next prime). */
266 #define TYPE_HASH_INITIAL_SIZE 1000
268 /* Now here is the hash table. When recording a type, it is added to
269 the slot whose index is the hash code. Note that the hash table is
270 used for several kinds of types (function types, array types and
271 array index range types, for now). While all these live in the
272 same table, they are completely independent, and the hash code is
273 computed differently for each of these. */
275 htab_t type_hash_table
;
277 static void build_real_from_int_cst_1
PARAMS ((PTR
));
278 static void set_type_quals
PARAMS ((tree
, int));
279 static void append_random_chars
PARAMS ((char *));
280 static void mark_type_hash
PARAMS ((void *));
281 static int type_hash_eq
PARAMS ((const void*, const void*));
282 static unsigned int type_hash_hash
PARAMS ((const void*));
283 static void print_type_hash_statistics
PARAMS((void));
284 static int mark_hash_entry
PARAMS((void **, void *));
286 /* If non-null, these are language-specific helper functions for
287 unsave_expr_now. If present, LANG_UNSAVE is called before its
288 argument (an UNSAVE_EXPR) is to be unsaved, and all other
289 processing in unsave_expr_now is aborted. LANG_UNSAVE_EXPR_NOW is
290 called from unsave_expr_1 for language-specific tree codes. */
291 void (*lang_unsave
) PARAMS ((tree
*));
292 void (*lang_unsave_expr_now
) PARAMS ((tree
));
294 /* The string used as a placeholder instead of a source file name for
295 built-in tree nodes. The variable, which is dynamically allocated,
296 should be used; the macro is only used to initialize it. */
298 static char *built_in_filename
;
299 #define BUILT_IN_FILENAME ("<built-in>")
301 tree global_trees
[TI_MAX
];
302 tree integer_types
[itk_none
];
304 /* Init the principal obstacks. */
309 gcc_obstack_init (&obstack_stack_obstack
);
310 gcc_obstack_init (&permanent_obstack
);
312 gcc_obstack_init (&temporary_obstack
);
313 temporary_firstobj
= (char *) obstack_alloc (&temporary_obstack
, 0);
314 gcc_obstack_init (&momentary_obstack
);
315 momentary_firstobj
= (char *) obstack_alloc (&momentary_obstack
, 0);
316 momentary_function_firstobj
= momentary_firstobj
;
317 gcc_obstack_init (&maybepermanent_obstack
);
318 maybepermanent_firstobj
319 = (char *) obstack_alloc (&maybepermanent_obstack
, 0);
320 gcc_obstack_init (&temp_decl_obstack
);
321 temp_decl_firstobj
= (char *) obstack_alloc (&temp_decl_obstack
, 0);
323 function_obstack
= &temporary_obstack
;
324 function_maybepermanent_obstack
= &maybepermanent_obstack
;
325 current_obstack
= &permanent_obstack
;
326 expression_obstack
= &permanent_obstack
;
327 rtl_obstack
= saveable_obstack
= &permanent_obstack
;
329 /* Init the hash table of identifiers. */
330 bzero ((char *) hash_table
, sizeof hash_table
);
331 ggc_add_tree_root (hash_table
, sizeof hash_table
/ sizeof (tree
));
333 /* Initialize the hash table of types. */
334 type_hash_table
= htab_create (TYPE_HASH_INITIAL_SIZE
, type_hash_hash
,
336 ggc_add_root (&type_hash_table
, 1, sizeof type_hash_table
, mark_type_hash
);
337 ggc_add_tree_root (global_trees
, TI_MAX
);
338 ggc_add_tree_root (integer_types
, itk_none
);
342 gcc_obstack_init (obstack
)
343 struct obstack
*obstack
;
345 /* Let particular systems override the size of a chunk. */
346 #ifndef OBSTACK_CHUNK_SIZE
347 #define OBSTACK_CHUNK_SIZE 0
349 /* Let them override the alloc and free routines too. */
350 #ifndef OBSTACK_CHUNK_ALLOC
351 #define OBSTACK_CHUNK_ALLOC xmalloc
353 #ifndef OBSTACK_CHUNK_FREE
354 #define OBSTACK_CHUNK_FREE free
356 _obstack_begin (obstack
, OBSTACK_CHUNK_SIZE
, 0,
357 (void *(*) PARAMS ((long))) OBSTACK_CHUNK_ALLOC
,
358 (void (*) PARAMS ((void *))) OBSTACK_CHUNK_FREE
);
361 /* Save all variables describing the current status into the structure
362 *P. This function is called whenever we start compiling one
363 function in the midst of compiling another. For example, when
364 compiling a nested function, or, in C++, a template instantiation
365 that is required by the function we are currently compiling.
367 CONTEXT is the decl_function_context for the function we're about to
368 compile; if it isn't current_function_decl, we have to play some games. */
374 p
->all_types_permanent
= all_types_permanent
;
375 p
->momentary_stack
= momentary_stack
;
376 p
->maybepermanent_firstobj
= maybepermanent_firstobj
;
377 p
->temporary_firstobj
= temporary_firstobj
;
378 p
->momentary_firstobj
= momentary_firstobj
;
379 p
->momentary_function_firstobj
= momentary_function_firstobj
;
380 p
->function_obstack
= function_obstack
;
381 p
->function_maybepermanent_obstack
= function_maybepermanent_obstack
;
382 p
->current_obstack
= current_obstack
;
383 p
->expression_obstack
= expression_obstack
;
384 p
->saveable_obstack
= saveable_obstack
;
385 p
->rtl_obstack
= rtl_obstack
;
387 function_maybepermanent_obstack
388 = (struct obstack
*) xmalloc (sizeof (struct obstack
));
389 gcc_obstack_init (function_maybepermanent_obstack
);
390 maybepermanent_firstobj
391 = (char *) obstack_finish (function_maybepermanent_obstack
);
393 function_obstack
= (struct obstack
*) xmalloc (sizeof (struct obstack
));
394 gcc_obstack_init (function_obstack
);
396 current_obstack
= &permanent_obstack
;
397 expression_obstack
= &permanent_obstack
;
398 rtl_obstack
= saveable_obstack
= &permanent_obstack
;
400 temporary_firstobj
= (char *) obstack_alloc (&temporary_obstack
, 0);
401 momentary_firstobj
= (char *) obstack_finish (&momentary_obstack
);
402 momentary_function_firstobj
= momentary_firstobj
;
405 /* Restore all variables describing the current status from the structure *P.
406 This is used after a nested function. */
409 restore_tree_status (p
)
412 all_types_permanent
= p
->all_types_permanent
;
413 momentary_stack
= p
->momentary_stack
;
415 obstack_free (&momentary_obstack
, momentary_function_firstobj
);
417 /* Free saveable storage used by the function just compiled and not
419 obstack_free (function_maybepermanent_obstack
, maybepermanent_firstobj
);
420 if (obstack_empty_p (function_maybepermanent_obstack
))
422 obstack_free (function_maybepermanent_obstack
, NULL
);
423 free (function_maybepermanent_obstack
);
426 obstack_free (&temporary_obstack
, temporary_firstobj
);
427 obstack_free (&momentary_obstack
, momentary_function_firstobj
);
429 obstack_free (function_obstack
, NULL
);
430 free (function_obstack
);
432 temporary_firstobj
= p
->temporary_firstobj
;
433 momentary_firstobj
= p
->momentary_firstobj
;
434 momentary_function_firstobj
= p
->momentary_function_firstobj
;
435 maybepermanent_firstobj
= p
->maybepermanent_firstobj
;
436 function_obstack
= p
->function_obstack
;
437 function_maybepermanent_obstack
= p
->function_maybepermanent_obstack
;
438 current_obstack
= p
->current_obstack
;
439 expression_obstack
= p
->expression_obstack
;
440 saveable_obstack
= p
->saveable_obstack
;
441 rtl_obstack
= p
->rtl_obstack
;
444 /* Start allocating on the temporary (per function) obstack.
445 This is done in start_function before parsing the function body,
446 and before each initialization at top level, and to go back
447 to temporary allocation after doing permanent_allocation. */
450 temporary_allocation ()
452 /* Note that function_obstack at top level points to temporary_obstack.
453 But within a nested function context, it is a separate obstack. */
454 current_obstack
= function_obstack
;
455 expression_obstack
= function_obstack
;
456 rtl_obstack
= saveable_obstack
= function_maybepermanent_obstack
;
460 /* Start allocating on the permanent obstack but don't
461 free the temporary data. After calling this, call
462 `permanent_allocation' to fully resume permanent allocation status. */
465 end_temporary_allocation ()
467 current_obstack
= &permanent_obstack
;
468 expression_obstack
= &permanent_obstack
;
469 rtl_obstack
= saveable_obstack
= &permanent_obstack
;
472 /* Resume allocating on the temporary obstack, undoing
473 effects of `end_temporary_allocation'. */
476 resume_temporary_allocation ()
478 current_obstack
= function_obstack
;
479 expression_obstack
= function_obstack
;
480 rtl_obstack
= saveable_obstack
= function_maybepermanent_obstack
;
483 /* While doing temporary allocation, switch to allocating in such a
484 way as to save all nodes if the function is inlined. Call
485 resume_temporary_allocation to go back to ordinary temporary
489 saveable_allocation ()
491 /* Note that function_obstack at top level points to temporary_obstack.
492 But within a nested function context, it is a separate obstack. */
493 expression_obstack
= current_obstack
= saveable_obstack
;
496 /* Switch to current obstack CURRENT and maybepermanent obstack SAVEABLE,
497 recording the previously current obstacks on a stack.
498 This does not free any storage in any obstack. */
501 push_obstacks (current
, saveable
)
502 struct obstack
*current
, *saveable
;
504 struct obstack_stack
*p
;
506 p
= (struct obstack_stack
*) obstack_alloc (&obstack_stack_obstack
,
507 (sizeof (struct obstack_stack
)));
509 p
->current
= current_obstack
;
510 p
->saveable
= saveable_obstack
;
511 p
->expression
= expression_obstack
;
512 p
->rtl
= rtl_obstack
;
513 p
->next
= obstack_stack
;
516 current_obstack
= current
;
517 expression_obstack
= current
;
518 rtl_obstack
= saveable_obstack
= saveable
;
521 /* Save the current set of obstacks, but don't change them. */
524 push_obstacks_nochange ()
526 struct obstack_stack
*p
;
528 p
= (struct obstack_stack
*) obstack_alloc (&obstack_stack_obstack
,
529 (sizeof (struct obstack_stack
)));
531 p
->current
= current_obstack
;
532 p
->saveable
= saveable_obstack
;
533 p
->expression
= expression_obstack
;
534 p
->rtl
= rtl_obstack
;
535 p
->next
= obstack_stack
;
539 /* Pop the obstack selection stack. */
544 struct obstack_stack
*p
;
547 obstack_stack
= p
->next
;
549 current_obstack
= p
->current
;
550 saveable_obstack
= p
->saveable
;
551 expression_obstack
= p
->expression
;
552 rtl_obstack
= p
->rtl
;
554 obstack_free (&obstack_stack_obstack
, p
);
557 /* Nonzero if temporary allocation is currently in effect.
558 Zero if currently doing permanent allocation. */
561 allocation_temporary_p ()
563 return current_obstack
!= &permanent_obstack
;
566 /* Go back to allocating on the permanent obstack
567 and free everything in the temporary obstack.
569 FUNCTION_END is true only if we have just finished compiling a function.
570 In that case, we also free preserved initial values on the momentary
574 permanent_allocation (function_end
)
577 /* Free up previous temporary obstack data */
578 obstack_free (&temporary_obstack
, temporary_firstobj
);
581 obstack_free (&momentary_obstack
, momentary_function_firstobj
);
582 momentary_firstobj
= momentary_function_firstobj
;
585 obstack_free (&momentary_obstack
, momentary_firstobj
);
587 obstack_free (function_maybepermanent_obstack
, maybepermanent_firstobj
);
588 obstack_free (&temp_decl_obstack
, temp_decl_firstobj
);
590 current_obstack
= &permanent_obstack
;
591 expression_obstack
= &permanent_obstack
;
592 rtl_obstack
= saveable_obstack
= &permanent_obstack
;
595 /* Save permanently everything on the maybepermanent_obstack. */
600 maybepermanent_firstobj
601 = (char *) obstack_alloc (function_maybepermanent_obstack
, 0);
605 preserve_initializer ()
607 struct momentary_level
*tem
;
611 = (char *) obstack_alloc (&temporary_obstack
, 0);
612 maybepermanent_firstobj
613 = (char *) obstack_alloc (function_maybepermanent_obstack
, 0);
615 old_momentary
= momentary_firstobj
;
617 = (char *) obstack_alloc (&momentary_obstack
, 0);
618 if (momentary_firstobj
!= old_momentary
)
619 for (tem
= momentary_stack
; tem
; tem
= tem
->prev
)
620 tem
->base
= momentary_firstobj
;
623 /* Start allocating new rtl in current_obstack.
624 Use resume_temporary_allocation
625 to go back to allocating rtl in saveable_obstack. */
628 rtl_in_current_obstack ()
630 rtl_obstack
= current_obstack
;
633 /* Start allocating rtl from saveable_obstack. Intended to be used after
634 a call to push_obstacks_nochange. */
637 rtl_in_saveable_obstack ()
639 rtl_obstack
= saveable_obstack
;
642 /* Allocate SIZE bytes in the current obstack
643 and return a pointer to them.
644 In practice the current obstack is always the temporary one. */
650 return (char *) obstack_alloc (current_obstack
, size
);
653 /* Free the object PTR in the current obstack
654 as well as everything allocated since PTR.
655 In practice the current obstack is always the temporary one. */
661 obstack_free (current_obstack
, ptr
);
664 /* Allocate SIZE bytes in the permanent obstack
665 and return a pointer to them. */
671 return (char *) obstack_alloc (&permanent_obstack
, size
);
674 /* Allocate NELEM items of SIZE bytes in the permanent obstack
675 and return a pointer to them. The storage is cleared before
676 returning the value. */
679 perm_calloc (nelem
, size
)
683 char *rval
= (char *) obstack_alloc (&permanent_obstack
, nelem
* size
);
684 bzero (rval
, nelem
* size
);
688 /* Allocate SIZE bytes in the saveable obstack
689 and return a pointer to them. */
695 return (char *) obstack_alloc (saveable_obstack
, size
);
698 /* Allocate SIZE bytes in the expression obstack
699 and return a pointer to them. */
705 return (char *) obstack_alloc (expression_obstack
, size
);
708 /* Print out which obstack an object is in. */
711 print_obstack_name (object
, file
, prefix
)
716 struct obstack
*obstack
= NULL
;
717 const char *obstack_name
= NULL
;
720 for (p
= outer_function_chain
; p
; p
= p
->next
)
722 if (_obstack_allocated_p (p
->function_obstack
, object
))
724 obstack
= p
->function_obstack
;
725 obstack_name
= "containing function obstack";
727 if (_obstack_allocated_p (p
->function_maybepermanent_obstack
, object
))
729 obstack
= p
->function_maybepermanent_obstack
;
730 obstack_name
= "containing function maybepermanent obstack";
734 if (_obstack_allocated_p (&obstack_stack_obstack
, object
))
736 obstack
= &obstack_stack_obstack
;
737 obstack_name
= "obstack_stack_obstack";
739 else if (_obstack_allocated_p (function_obstack
, object
))
741 obstack
= function_obstack
;
742 obstack_name
= "function obstack";
744 else if (_obstack_allocated_p (&permanent_obstack
, object
))
746 obstack
= &permanent_obstack
;
747 obstack_name
= "permanent_obstack";
749 else if (_obstack_allocated_p (&momentary_obstack
, object
))
751 obstack
= &momentary_obstack
;
752 obstack_name
= "momentary_obstack";
754 else if (_obstack_allocated_p (function_maybepermanent_obstack
, object
))
756 obstack
= function_maybepermanent_obstack
;
757 obstack_name
= "function maybepermanent obstack";
759 else if (_obstack_allocated_p (&temp_decl_obstack
, object
))
761 obstack
= &temp_decl_obstack
;
762 obstack_name
= "temp_decl_obstack";
765 /* Check to see if the object is in the free area of the obstack. */
768 if (object
>= obstack
->next_free
769 && object
< obstack
->chunk_limit
)
770 fprintf (file
, "%s in free portion of obstack %s",
771 prefix
, obstack_name
);
773 fprintf (file
, "%s allocated from %s", prefix
, obstack_name
);
776 fprintf (file
, "%s not allocated from any obstack", prefix
);
780 debug_obstack (object
)
783 print_obstack_name (object
, stderr
, "object");
784 fprintf (stderr
, ".\n");
787 /* Return 1 if OBJ is in the permanent obstack.
788 This is slow, and should be used only for debugging.
789 Use TREE_PERMANENT for other purposes. */
792 object_permanent_p (obj
)
795 return _obstack_allocated_p (&permanent_obstack
, obj
);
798 /* Start a level of momentary allocation.
799 In C, each compound statement has its own level
800 and that level is freed at the end of each statement.
801 All expression nodes are allocated in the momentary allocation level. */
806 struct momentary_level
*tem
807 = (struct momentary_level
*) obstack_alloc (&momentary_obstack
,
808 sizeof (struct momentary_level
));
809 tem
->prev
= momentary_stack
;
810 tem
->base
= (char *) obstack_base (&momentary_obstack
);
811 tem
->obstack
= expression_obstack
;
812 momentary_stack
= tem
;
813 expression_obstack
= &momentary_obstack
;
816 /* Set things up so the next clear_momentary will only clear memory
817 past our present position in momentary_obstack. */
820 preserve_momentary ()
822 momentary_stack
->base
= (char *) obstack_base (&momentary_obstack
);
825 /* Free all the storage in the current momentary-allocation level.
826 In C, this happens at the end of each statement. */
831 obstack_free (&momentary_obstack
, momentary_stack
->base
);
834 /* Discard a level of momentary allocation.
835 In C, this happens at the end of each compound statement.
836 Restore the status of expression node allocation
837 that was in effect before this level was created. */
842 struct momentary_level
*tem
= momentary_stack
;
843 momentary_stack
= tem
->prev
;
844 expression_obstack
= tem
->obstack
;
845 /* We can't free TEM from the momentary_obstack, because there might
846 be objects above it which have been saved. We can free back to the
847 stack of the level we are popping off though. */
848 obstack_free (&momentary_obstack
, tem
->base
);
851 /* Pop back to the previous level of momentary allocation,
852 but don't free any momentary data just yet. */
855 pop_momentary_nofree ()
857 struct momentary_level
*tem
= momentary_stack
;
858 momentary_stack
= tem
->prev
;
859 expression_obstack
= tem
->obstack
;
862 /* Call when starting to parse a declaration:
863 make expressions in the declaration last the length of the function.
864 Returns an argument that should be passed to resume_momentary later. */
869 register int tem
= expression_obstack
== &momentary_obstack
;
870 expression_obstack
= saveable_obstack
;
874 /* Call when finished parsing a declaration:
875 restore the treatment of node-allocation that was
876 in effect before the suspension.
877 YES should be the value previously returned by suspend_momentary. */
880 resume_momentary (yes
)
884 expression_obstack
= &momentary_obstack
;
887 /* Init the tables indexed by tree code.
888 Note that languages can add to these tables to define their own codes. */
894 = ggc_alloc_string (BUILT_IN_FILENAME
, sizeof (BUILT_IN_FILENAME
));
895 ggc_add_string_root (&built_in_filename
, 1);
898 /* Return a newly allocated node of code CODE.
899 Initialize the node's unique id and its TREE_PERMANENT flag.
900 Note that if garbage collection is in use, TREE_PERMANENT will
901 always be zero - we want to eliminate use of TREE_PERMANENT.
902 For decl and type nodes, some other fields are initialized.
903 The rest of the node is initialized to zero.
905 Achoo! I got a code in the node. */
912 register int type
= TREE_CODE_CLASS (code
);
913 register int length
= 0;
914 register struct obstack
*obstack
= current_obstack
;
915 #ifdef GATHER_STATISTICS
916 register tree_node_kind kind
;
921 case 'd': /* A decl node */
922 #ifdef GATHER_STATISTICS
925 length
= sizeof (struct tree_decl
);
926 /* All decls in an inline function need to be saved. */
927 if (obstack
!= &permanent_obstack
)
928 obstack
= saveable_obstack
;
930 /* PARM_DECLs go on the context of the parent. If this is a nested
931 function, then we must allocate the PARM_DECL on the parent's
932 obstack, so that they will live to the end of the parent's
933 closing brace. This is necessary in case we try to inline the
934 function into its parent.
936 PARM_DECLs of top-level functions do not have this problem. However,
937 we allocate them where we put the FUNCTION_DECL for languages such as
938 Ada that need to consult some flags in the PARM_DECLs of the function
941 See comment in restore_tree_status for why we can't put this
942 in function_obstack. */
943 if (code
== PARM_DECL
&& obstack
!= &permanent_obstack
)
946 if (current_function_decl
)
947 context
= decl_function_context (current_function_decl
);
951 = find_function_data (context
)->function_maybepermanent_obstack
;
955 case 't': /* a type node */
956 #ifdef GATHER_STATISTICS
959 length
= sizeof (struct tree_type
);
960 /* All data types are put where we can preserve them if nec. */
961 if (obstack
!= &permanent_obstack
)
962 obstack
= all_types_permanent
? &permanent_obstack
: saveable_obstack
;
965 case 'b': /* a lexical block */
966 #ifdef GATHER_STATISTICS
969 length
= sizeof (struct tree_block
);
970 /* All BLOCK nodes are put where we can preserve them if nec. */
971 if (obstack
!= &permanent_obstack
)
972 obstack
= saveable_obstack
;
975 case 's': /* an expression with side effects */
976 #ifdef GATHER_STATISTICS
980 case 'r': /* a reference */
981 #ifdef GATHER_STATISTICS
985 case 'e': /* an expression */
986 case '<': /* a comparison expression */
987 case '1': /* a unary arithmetic expression */
988 case '2': /* a binary arithmetic expression */
989 #ifdef GATHER_STATISTICS
993 obstack
= expression_obstack
;
994 /* All BIND_EXPR nodes are put where we can preserve them if nec. */
995 if (code
== BIND_EXPR
&& obstack
!= &permanent_obstack
)
996 obstack
= saveable_obstack
;
997 length
= sizeof (struct tree_exp
)
998 + (tree_code_length
[(int) code
] - 1) * sizeof (char *);
1001 case 'c': /* a constant */
1002 #ifdef GATHER_STATISTICS
1005 obstack
= expression_obstack
;
1007 /* We can't use tree_code_length for INTEGER_CST, since the number of
1008 words is machine-dependent due to varying length of HOST_WIDE_INT,
1009 which might be wider than a pointer (e.g., long long). Similarly
1010 for REAL_CST, since the number of words is machine-dependent due
1011 to varying size and alignment of `double'. */
1013 if (code
== INTEGER_CST
)
1014 length
= sizeof (struct tree_int_cst
);
1015 else if (code
== REAL_CST
)
1016 length
= sizeof (struct tree_real_cst
);
1018 length
= sizeof (struct tree_common
)
1019 + tree_code_length
[(int) code
] * sizeof (char *);
1022 case 'x': /* something random, like an identifier. */
1023 #ifdef GATHER_STATISTICS
1024 if (code
== IDENTIFIER_NODE
)
1026 else if (code
== OP_IDENTIFIER
)
1028 else if (code
== TREE_VEC
)
1033 length
= sizeof (struct tree_common
)
1034 + tree_code_length
[(int) code
] * sizeof (char *);
1035 /* Identifier nodes are always permanent since they are
1036 unique in a compiler run. */
1037 if (code
== IDENTIFIER_NODE
) obstack
= &permanent_obstack
;
1045 t
= ggc_alloc_tree (length
);
1048 t
= (tree
) obstack_alloc (obstack
, length
);
1049 memset ((PTR
) t
, 0, length
);
1052 #ifdef GATHER_STATISTICS
1053 tree_node_counts
[(int)kind
]++;
1054 tree_node_sizes
[(int)kind
] += length
;
1057 TREE_SET_CODE (t
, code
);
1058 TREE_SET_PERMANENT (t
);
1063 TREE_SIDE_EFFECTS (t
) = 1;
1064 TREE_TYPE (t
) = void_type_node
;
1068 if (code
!= FUNCTION_DECL
)
1070 DECL_IN_SYSTEM_HEADER (t
) = in_system_header
;
1071 DECL_SOURCE_LINE (t
) = lineno
;
1072 DECL_SOURCE_FILE (t
) =
1073 (input_filename
) ? input_filename
: built_in_filename
;
1074 DECL_UID (t
) = next_decl_uid
++;
1075 /* Note that we have not yet computed the alias set for this
1077 DECL_POINTER_ALIAS_SET (t
) = -1;
1081 TYPE_UID (t
) = next_type_uid
++;
1083 TYPE_MAIN_VARIANT (t
) = t
;
1084 TYPE_OBSTACK (t
) = obstack
;
1085 TYPE_ATTRIBUTES (t
) = NULL_TREE
;
1086 #ifdef SET_DEFAULT_TYPE_ATTRIBUTES
1087 SET_DEFAULT_TYPE_ATTRIBUTES (t
);
1089 /* Note that we have not yet computed the alias set for this
1091 TYPE_ALIAS_SET (t
) = -1;
1095 TREE_CONSTANT (t
) = 1;
1105 case PREDECREMENT_EXPR
:
1106 case PREINCREMENT_EXPR
:
1107 case POSTDECREMENT_EXPR
:
1108 case POSTINCREMENT_EXPR
:
1109 /* All of these have side-effects, no matter what their
1111 TREE_SIDE_EFFECTS (t
) = 1;
1123 /* A front-end can reset this to an appropriate function if types need
1124 special handling. */
1126 tree (*make_lang_type_fn
) PARAMS ((enum tree_code
)) = make_node
;
1128 /* Return a new type (with the indicated CODE), doing whatever
1129 language-specific processing is required. */
1132 make_lang_type (code
)
1133 enum tree_code code
;
1135 return (*make_lang_type_fn
) (code
);
1138 /* Return a new node with the same contents as NODE except that its
1139 TREE_CHAIN is zero and it has a fresh uid. Unlike make_node, this
1140 function always performs the allocation on the CURRENT_OBSTACK;
1141 it's up to the caller to pick the right obstack before calling this
1149 register enum tree_code code
= TREE_CODE (node
);
1150 register int length
= 0;
1152 switch (TREE_CODE_CLASS (code
))
1154 case 'd': /* A decl node */
1155 length
= sizeof (struct tree_decl
);
1158 case 't': /* a type node */
1159 length
= sizeof (struct tree_type
);
1162 case 'b': /* a lexical block node */
1163 length
= sizeof (struct tree_block
);
1166 case 'r': /* a reference */
1167 case 'e': /* an expression */
1168 case 's': /* an expression with side effects */
1169 case '<': /* a comparison expression */
1170 case '1': /* a unary arithmetic expression */
1171 case '2': /* a binary arithmetic expression */
1172 length
= sizeof (struct tree_exp
)
1173 + (tree_code_length
[(int) code
] - 1) * sizeof (char *);
1176 case 'c': /* a constant */
1177 /* We can't use tree_code_length for INTEGER_CST, since the number of
1178 words is machine-dependent due to varying length of HOST_WIDE_INT,
1179 which might be wider than a pointer (e.g., long long). Similarly
1180 for REAL_CST, since the number of words is machine-dependent due
1181 to varying size and alignment of `double'. */
1182 if (code
== INTEGER_CST
)
1183 length
= sizeof (struct tree_int_cst
);
1184 else if (code
== REAL_CST
)
1185 length
= sizeof (struct tree_real_cst
);
1187 length
= (sizeof (struct tree_common
)
1188 + tree_code_length
[(int) code
] * sizeof (char *));
1191 case 'x': /* something random, like an identifier. */
1192 length
= sizeof (struct tree_common
)
1193 + tree_code_length
[(int) code
] * sizeof (char *);
1194 if (code
== TREE_VEC
)
1195 length
+= (TREE_VEC_LENGTH (node
) - 1) * sizeof (char *);
1199 t
= ggc_alloc_tree (length
);
1201 t
= (tree
) obstack_alloc (current_obstack
, length
);
1202 memcpy (t
, node
, length
);
1205 TREE_ASM_WRITTEN (t
) = 0;
1207 if (TREE_CODE_CLASS (code
) == 'd')
1208 DECL_UID (t
) = next_decl_uid
++;
1209 else if (TREE_CODE_CLASS (code
) == 't')
1211 TYPE_UID (t
) = next_type_uid
++;
1212 TYPE_OBSTACK (t
) = current_obstack
;
1214 /* The following is so that the debug code for
1215 the copy is different from the original type.
1216 The two statements usually duplicate each other
1217 (because they clear fields of the same union),
1218 but the optimizer should catch that. */
1219 TYPE_SYMTAB_POINTER (t
) = 0;
1220 TYPE_SYMTAB_ADDRESS (t
) = 0;
1223 TREE_SET_PERMANENT (t
);
1228 /* Return a copy of a chain of nodes, chained through the TREE_CHAIN field.
1229 For example, this can copy a list made of TREE_LIST nodes. */
1236 register tree prev
, next
;
1241 head
= prev
= copy_node (list
);
1242 next
= TREE_CHAIN (list
);
1245 TREE_CHAIN (prev
) = copy_node (next
);
1246 prev
= TREE_CHAIN (prev
);
1247 next
= TREE_CHAIN (next
);
1254 /* Return an IDENTIFIER_NODE whose name is TEXT (a null-terminated string).
1255 If an identifier with that name has previously been referred to,
1256 the same node is returned this time. */
1259 get_identifier (text
)
1260 register const char *text
;
1265 register int len
, hash_len
;
1267 /* Compute length of text in len. */
1268 len
= strlen (text
);
1270 /* Decide how much of that length to hash on */
1272 if (warn_id_clash
&& len
> id_clash_len
)
1273 hash_len
= id_clash_len
;
1275 /* Compute hash code */
1276 hi
= hash_len
* 613 + (unsigned) text
[0];
1277 for (i
= 1; i
< hash_len
; i
+= 2)
1278 hi
= ((hi
* 613) + (unsigned) (text
[i
]));
1280 hi
&= (1 << HASHBITS
) - 1;
1281 hi
%= MAX_HASH_TABLE
;
1283 /* Search table for identifier */
1284 for (idp
= hash_table
[hi
]; idp
; idp
= TREE_CHAIN (idp
))
1285 if (IDENTIFIER_LENGTH (idp
) == len
1286 && IDENTIFIER_POINTER (idp
)[0] == text
[0]
1287 && !bcmp (IDENTIFIER_POINTER (idp
), text
, len
))
1288 return idp
; /* <-- return if found */
1290 /* Not found; optionally warn about a similar identifier */
1291 if (warn_id_clash
&& do_identifier_warnings
&& len
>= id_clash_len
)
1292 for (idp
= hash_table
[hi
]; idp
; idp
= TREE_CHAIN (idp
))
1293 if (!strncmp (IDENTIFIER_POINTER (idp
), text
, id_clash_len
))
1295 warning ("`%s' and `%s' identical in first %d characters",
1296 IDENTIFIER_POINTER (idp
), text
, id_clash_len
);
1300 if (tree_code_length
[(int) IDENTIFIER_NODE
] < 0)
1301 abort (); /* set_identifier_size hasn't been called. */
1303 /* Not found, create one, add to chain */
1304 idp
= make_node (IDENTIFIER_NODE
);
1305 IDENTIFIER_LENGTH (idp
) = len
;
1306 #ifdef GATHER_STATISTICS
1307 id_string_size
+= len
;
1311 IDENTIFIER_POINTER (idp
) = ggc_alloc_string (text
, len
);
1313 IDENTIFIER_POINTER (idp
) = obstack_copy0 (&permanent_obstack
, text
, len
);
1315 TREE_CHAIN (idp
) = hash_table
[hi
];
1316 hash_table
[hi
] = idp
;
1317 return idp
; /* <-- return if created */
1320 /* If an identifier with the name TEXT (a null-terminated string) has
1321 previously been referred to, return that node; otherwise return
1325 maybe_get_identifier (text
)
1326 register const char *text
;
1331 register int len
, hash_len
;
1333 /* Compute length of text in len. */
1334 len
= strlen (text
);
1336 /* Decide how much of that length to hash on */
1338 if (warn_id_clash
&& len
> id_clash_len
)
1339 hash_len
= id_clash_len
;
1341 /* Compute hash code */
1342 hi
= hash_len
* 613 + (unsigned) text
[0];
1343 for (i
= 1; i
< hash_len
; i
+= 2)
1344 hi
= ((hi
* 613) + (unsigned) (text
[i
]));
1346 hi
&= (1 << HASHBITS
) - 1;
1347 hi
%= MAX_HASH_TABLE
;
1349 /* Search table for identifier */
1350 for (idp
= hash_table
[hi
]; idp
; idp
= TREE_CHAIN (idp
))
1351 if (IDENTIFIER_LENGTH (idp
) == len
1352 && IDENTIFIER_POINTER (idp
)[0] == text
[0]
1353 && !bcmp (IDENTIFIER_POINTER (idp
), text
, len
))
1354 return idp
; /* <-- return if found */
1359 /* Enable warnings on similar identifiers (if requested).
1360 Done after the built-in identifiers are created. */
1363 start_identifier_warnings ()
1365 do_identifier_warnings
= 1;
1368 /* Record the size of an identifier node for the language in use.
1369 SIZE is the total size in bytes.
1370 This is called by the language-specific files. This must be
1371 called before allocating any identifiers. */
1374 set_identifier_size (size
)
1377 tree_code_length
[(int) IDENTIFIER_NODE
]
1378 = (size
- sizeof (struct tree_common
)) / sizeof (tree
);
1381 /* Return a newly constructed INTEGER_CST node whose constant value
1382 is specified by the two ints LOW and HI.
1383 The TREE_TYPE is set to `int'.
1385 This function should be used via the `build_int_2' macro. */
1388 build_int_2_wide (low
, hi
)
1389 HOST_WIDE_INT low
, hi
;
1391 register tree t
= make_node (INTEGER_CST
);
1393 TREE_INT_CST_LOW (t
) = low
;
1394 TREE_INT_CST_HIGH (t
) = hi
;
1395 TREE_TYPE (t
) = integer_type_node
;
1399 /* Return a new REAL_CST node whose type is TYPE and value is D. */
1402 build_real (type
, d
)
1409 /* Check for valid float value for this type on this target machine;
1410 if not, can print error message and store a valid value in D. */
1411 #ifdef CHECK_FLOAT_VALUE
1412 CHECK_FLOAT_VALUE (TYPE_MODE (type
), d
, overflow
);
1415 v
= make_node (REAL_CST
);
1416 TREE_TYPE (v
) = type
;
1417 TREE_REAL_CST (v
) = d
;
1418 TREE_OVERFLOW (v
) = TREE_CONSTANT_OVERFLOW (v
) = overflow
;
1422 /* Return a new REAL_CST node whose type is TYPE
1423 and whose value is the integer value of the INTEGER_CST node I. */
1425 #if !defined (REAL_IS_NOT_DOUBLE) || defined (REAL_ARITHMETIC)
1428 real_value_from_int_cst (type
, i
)
1429 tree type ATTRIBUTE_UNUSED
, i
;
1433 #ifdef REAL_ARITHMETIC
1434 /* Clear all bits of the real value type so that we can later do
1435 bitwise comparisons to see if two values are the same. */
1436 bzero ((char *) &d
, sizeof d
);
1438 if (! TREE_UNSIGNED (TREE_TYPE (i
)))
1439 REAL_VALUE_FROM_INT (d
, TREE_INT_CST_LOW (i
), TREE_INT_CST_HIGH (i
),
1442 REAL_VALUE_FROM_UNSIGNED_INT (d
, TREE_INT_CST_LOW (i
),
1443 TREE_INT_CST_HIGH (i
), TYPE_MODE (type
));
1444 #else /* not REAL_ARITHMETIC */
1445 /* Some 386 compilers mishandle unsigned int to float conversions,
1446 so introduce a temporary variable E to avoid those bugs. */
1447 if (TREE_INT_CST_HIGH (i
) < 0 && ! TREE_UNSIGNED (TREE_TYPE (i
)))
1451 d
= (double) (~ TREE_INT_CST_HIGH (i
));
1452 e
= ((double) ((HOST_WIDE_INT
) 1 << (HOST_BITS_PER_WIDE_INT
/ 2))
1453 * (double) ((HOST_WIDE_INT
) 1 << (HOST_BITS_PER_WIDE_INT
/ 2)));
1455 e
= (double) (~ TREE_INT_CST_LOW (i
));
1463 d
= (double) (unsigned HOST_WIDE_INT
) TREE_INT_CST_HIGH (i
);
1464 e
= ((double) ((HOST_WIDE_INT
) 1 << (HOST_BITS_PER_WIDE_INT
/ 2))
1465 * (double) ((HOST_WIDE_INT
) 1 << (HOST_BITS_PER_WIDE_INT
/ 2)));
1467 e
= (double) TREE_INT_CST_LOW (i
);
1470 #endif /* not REAL_ARITHMETIC */
1474 /* Args to pass to and from build_real_from_int_cst_1. */
1478 tree type
; /* Input: type to conver to. */
1479 tree i
; /* Input: operand to convert */
1480 REAL_VALUE_TYPE d
; /* Output: floating point value. */
1483 /* Convert an integer to a floating point value while protected by a floating
1484 point exception handler. */
1487 build_real_from_int_cst_1 (data
)
1490 struct brfic_args
*args
= (struct brfic_args
*) data
;
1492 #ifdef REAL_ARITHMETIC
1493 args
->d
= real_value_from_int_cst (args
->type
, args
->i
);
1496 = REAL_VALUE_TRUNCATE (TYPE_MODE (args
->type
),
1497 real_value_from_int_cst (args
->type
, args
->i
));
1501 /* Given a tree representing an integer constant I, return a tree
1502 representing the same value as a floating-point constant of type TYPE.
1503 We cannot perform this operation if there is no way of doing arithmetic
1504 on floating-point values. */
1507 build_real_from_int_cst (type
, i
)
1512 int overflow
= TREE_OVERFLOW (i
);
1514 struct brfic_args args
;
1516 v
= make_node (REAL_CST
);
1517 TREE_TYPE (v
) = type
;
1519 /* Setup input for build_real_from_int_cst_1() */
1523 if (do_float_handler (build_real_from_int_cst_1
, (PTR
) &args
))
1524 /* Receive output from build_real_from_int_cst_1() */
1528 /* We got an exception from build_real_from_int_cst_1() */
1533 /* Check for valid float value for this type on this target machine. */
1535 #ifdef CHECK_FLOAT_VALUE
1536 CHECK_FLOAT_VALUE (TYPE_MODE (type
), d
, overflow
);
1539 TREE_REAL_CST (v
) = d
;
1540 TREE_OVERFLOW (v
) = TREE_CONSTANT_OVERFLOW (v
) = overflow
;
1544 #endif /* not REAL_IS_NOT_DOUBLE, or REAL_ARITHMETIC */
1546 /* Return a newly constructed STRING_CST node whose value is
1547 the LEN characters at STR.
1548 The TREE_TYPE is not initialized. */
1551 build_string (len
, str
)
1555 /* Put the string in saveable_obstack since it will be placed in the RTL
1556 for an "asm" statement and will also be kept around a while if
1557 deferring constant output in varasm.c. */
1559 register tree s
= make_node (STRING_CST
);
1561 TREE_STRING_LENGTH (s
) = len
;
1563 TREE_STRING_POINTER (s
) = ggc_alloc_string (str
, len
);
1565 TREE_STRING_POINTER (s
) = obstack_copy0 (saveable_obstack
, str
, len
);
1570 /* Return a newly constructed COMPLEX_CST node whose value is
1571 specified by the real and imaginary parts REAL and IMAG.
1572 Both REAL and IMAG should be constant nodes. TYPE, if specified,
1573 will be the type of the COMPLEX_CST; otherwise a new type will be made. */
1576 build_complex (type
, real
, imag
)
1580 register tree t
= make_node (COMPLEX_CST
);
1582 TREE_REALPART (t
) = real
;
1583 TREE_IMAGPART (t
) = imag
;
1584 TREE_TYPE (t
) = type
? type
: build_complex_type (TREE_TYPE (real
));
1585 TREE_OVERFLOW (t
) = TREE_OVERFLOW (real
) | TREE_OVERFLOW (imag
);
1586 TREE_CONSTANT_OVERFLOW (t
)
1587 = TREE_CONSTANT_OVERFLOW (real
) | TREE_CONSTANT_OVERFLOW (imag
);
1591 /* Build a newly constructed TREE_VEC node of length LEN. */
1598 register int length
= (len
-1) * sizeof (tree
) + sizeof (struct tree_vec
);
1599 register struct obstack
*obstack
= current_obstack
;
1601 #ifdef GATHER_STATISTICS
1602 tree_node_counts
[(int)vec_kind
]++;
1603 tree_node_sizes
[(int)vec_kind
] += length
;
1607 t
= ggc_alloc_tree (length
);
1610 t
= (tree
) obstack_alloc (obstack
, length
);
1611 bzero ((PTR
) t
, length
);
1614 TREE_SET_CODE (t
, TREE_VEC
);
1615 TREE_VEC_LENGTH (t
) = len
;
1616 TREE_SET_PERMANENT (t
);
1621 /* Return 1 if EXPR is the integer constant zero or a complex constant
1625 integer_zerop (expr
)
1630 return ((TREE_CODE (expr
) == INTEGER_CST
1631 && ! TREE_CONSTANT_OVERFLOW (expr
)
1632 && TREE_INT_CST_LOW (expr
) == 0
1633 && TREE_INT_CST_HIGH (expr
) == 0)
1634 || (TREE_CODE (expr
) == COMPLEX_CST
1635 && integer_zerop (TREE_REALPART (expr
))
1636 && integer_zerop (TREE_IMAGPART (expr
))));
1639 /* Return 1 if EXPR is the integer constant one or the corresponding
1640 complex constant. */
1648 return ((TREE_CODE (expr
) == INTEGER_CST
1649 && ! TREE_CONSTANT_OVERFLOW (expr
)
1650 && TREE_INT_CST_LOW (expr
) == 1
1651 && TREE_INT_CST_HIGH (expr
) == 0)
1652 || (TREE_CODE (expr
) == COMPLEX_CST
1653 && integer_onep (TREE_REALPART (expr
))
1654 && integer_zerop (TREE_IMAGPART (expr
))));
1657 /* Return 1 if EXPR is an integer containing all 1's in as much precision as
1658 it contains. Likewise for the corresponding complex constant. */
1661 integer_all_onesp (expr
)
1669 if (TREE_CODE (expr
) == COMPLEX_CST
1670 && integer_all_onesp (TREE_REALPART (expr
))
1671 && integer_zerop (TREE_IMAGPART (expr
)))
1674 else if (TREE_CODE (expr
) != INTEGER_CST
1675 || TREE_CONSTANT_OVERFLOW (expr
))
1678 uns
= TREE_UNSIGNED (TREE_TYPE (expr
));
1680 return (TREE_INT_CST_LOW (expr
) == ~ (unsigned HOST_WIDE_INT
) 0
1681 && TREE_INT_CST_HIGH (expr
) == -1);
1683 /* Note that using TYPE_PRECISION here is wrong. We care about the
1684 actual bits, not the (arbitrary) range of the type. */
1685 prec
= GET_MODE_BITSIZE (TYPE_MODE (TREE_TYPE (expr
)));
1686 if (prec
>= HOST_BITS_PER_WIDE_INT
)
1688 HOST_WIDE_INT high_value
;
1691 shift_amount
= prec
- HOST_BITS_PER_WIDE_INT
;
1693 if (shift_amount
> HOST_BITS_PER_WIDE_INT
)
1694 /* Can not handle precisions greater than twice the host int size. */
1696 else if (shift_amount
== HOST_BITS_PER_WIDE_INT
)
1697 /* Shifting by the host word size is undefined according to the ANSI
1698 standard, so we must handle this as a special case. */
1701 high_value
= ((HOST_WIDE_INT
) 1 << shift_amount
) - 1;
1703 return (TREE_INT_CST_LOW (expr
) == ~ (unsigned HOST_WIDE_INT
) 0
1704 && TREE_INT_CST_HIGH (expr
) == high_value
);
1707 return TREE_INT_CST_LOW (expr
) == ((unsigned HOST_WIDE_INT
) 1 << prec
) - 1;
1710 /* Return 1 if EXPR is an integer constant that is a power of 2 (i.e., has only
1714 integer_pow2p (expr
)
1718 HOST_WIDE_INT high
, low
;
1722 if (TREE_CODE (expr
) == COMPLEX_CST
1723 && integer_pow2p (TREE_REALPART (expr
))
1724 && integer_zerop (TREE_IMAGPART (expr
)))
1727 if (TREE_CODE (expr
) != INTEGER_CST
|| TREE_CONSTANT_OVERFLOW (expr
))
1730 prec
= (POINTER_TYPE_P (TREE_TYPE (expr
))
1731 ? POINTER_SIZE
: TYPE_PRECISION (TREE_TYPE (expr
)));
1732 high
= TREE_INT_CST_HIGH (expr
);
1733 low
= TREE_INT_CST_LOW (expr
);
1735 /* First clear all bits that are beyond the type's precision in case
1736 we've been sign extended. */
1738 if (prec
== 2 * HOST_BITS_PER_WIDE_INT
)
1740 else if (prec
> HOST_BITS_PER_WIDE_INT
)
1741 high
&= ~((HOST_WIDE_INT
) (-1) << (prec
- HOST_BITS_PER_WIDE_INT
));
1745 if (prec
< HOST_BITS_PER_WIDE_INT
)
1746 low
&= ~((HOST_WIDE_INT
) (-1) << prec
);
1749 if (high
== 0 && low
== 0)
1752 return ((high
== 0 && (low
& (low
- 1)) == 0)
1753 || (low
== 0 && (high
& (high
- 1)) == 0));
1756 /* Return the power of two represented by a tree node known to be a
1764 HOST_WIDE_INT high
, low
;
1768 if (TREE_CODE (expr
) == COMPLEX_CST
)
1769 return tree_log2 (TREE_REALPART (expr
));
1771 prec
= (POINTER_TYPE_P (TREE_TYPE (expr
))
1772 ? POINTER_SIZE
: TYPE_PRECISION (TREE_TYPE (expr
)));
1774 high
= TREE_INT_CST_HIGH (expr
);
1775 low
= TREE_INT_CST_LOW (expr
);
1777 /* First clear all bits that are beyond the type's precision in case
1778 we've been sign extended. */
1780 if (prec
== 2 * HOST_BITS_PER_WIDE_INT
)
1782 else if (prec
> HOST_BITS_PER_WIDE_INT
)
1783 high
&= ~((HOST_WIDE_INT
) (-1) << (prec
- HOST_BITS_PER_WIDE_INT
));
1787 if (prec
< HOST_BITS_PER_WIDE_INT
)
1788 low
&= ~((HOST_WIDE_INT
) (-1) << prec
);
1791 return (high
!= 0 ? HOST_BITS_PER_WIDE_INT
+ exact_log2 (high
)
1792 : exact_log2 (low
));
1795 /* Similar, but return the largest integer Y such that 2 ** Y is less
1796 than or equal to EXPR. */
1799 tree_floor_log2 (expr
)
1803 HOST_WIDE_INT high
, low
;
1807 if (TREE_CODE (expr
) == COMPLEX_CST
)
1808 return tree_log2 (TREE_REALPART (expr
));
1810 prec
= (POINTER_TYPE_P (TREE_TYPE (expr
))
1811 ? POINTER_SIZE
: TYPE_PRECISION (TREE_TYPE (expr
)));
1813 high
= TREE_INT_CST_HIGH (expr
);
1814 low
= TREE_INT_CST_LOW (expr
);
1816 /* First clear all bits that are beyond the type's precision in case
1817 we've been sign extended. Ignore if type's precision hasn't been set
1818 since what we are doing is setting it. */
1820 if (prec
== 2 * HOST_BITS_PER_WIDE_INT
|| prec
== 0)
1822 else if (prec
> HOST_BITS_PER_WIDE_INT
)
1823 high
&= ~((HOST_WIDE_INT
) (-1) << (prec
- HOST_BITS_PER_WIDE_INT
));
1827 if (prec
< HOST_BITS_PER_WIDE_INT
)
1828 low
&= ~((HOST_WIDE_INT
) (-1) << prec
);
1831 return (high
!= 0 ? HOST_BITS_PER_WIDE_INT
+ floor_log2 (high
)
1832 : floor_log2 (low
));
1835 /* Return 1 if EXPR is the real constant zero. */
1843 return ((TREE_CODE (expr
) == REAL_CST
1844 && ! TREE_CONSTANT_OVERFLOW (expr
)
1845 && REAL_VALUES_EQUAL (TREE_REAL_CST (expr
), dconst0
))
1846 || (TREE_CODE (expr
) == COMPLEX_CST
1847 && real_zerop (TREE_REALPART (expr
))
1848 && real_zerop (TREE_IMAGPART (expr
))));
1851 /* Return 1 if EXPR is the real constant one in real or complex form. */
1859 return ((TREE_CODE (expr
) == REAL_CST
1860 && ! TREE_CONSTANT_OVERFLOW (expr
)
1861 && REAL_VALUES_EQUAL (TREE_REAL_CST (expr
), dconst1
))
1862 || (TREE_CODE (expr
) == COMPLEX_CST
1863 && real_onep (TREE_REALPART (expr
))
1864 && real_zerop (TREE_IMAGPART (expr
))));
1867 /* Return 1 if EXPR is the real constant two. */
1875 return ((TREE_CODE (expr
) == REAL_CST
1876 && ! TREE_CONSTANT_OVERFLOW (expr
)
1877 && REAL_VALUES_EQUAL (TREE_REAL_CST (expr
), dconst2
))
1878 || (TREE_CODE (expr
) == COMPLEX_CST
1879 && real_twop (TREE_REALPART (expr
))
1880 && real_zerop (TREE_IMAGPART (expr
))));
1883 /* Nonzero if EXP is a constant or a cast of a constant. */
1886 really_constant_p (exp
)
1889 /* This is not quite the same as STRIP_NOPS. It does more. */
1890 while (TREE_CODE (exp
) == NOP_EXPR
1891 || TREE_CODE (exp
) == CONVERT_EXPR
1892 || TREE_CODE (exp
) == NON_LVALUE_EXPR
)
1893 exp
= TREE_OPERAND (exp
, 0);
1894 return TREE_CONSTANT (exp
);
1897 /* Return first list element whose TREE_VALUE is ELEM.
1898 Return 0 if ELEM is not in LIST. */
1901 value_member (elem
, list
)
1906 if (elem
== TREE_VALUE (list
))
1908 list
= TREE_CHAIN (list
);
1913 /* Return first list element whose TREE_PURPOSE is ELEM.
1914 Return 0 if ELEM is not in LIST. */
1917 purpose_member (elem
, list
)
1922 if (elem
== TREE_PURPOSE (list
))
1924 list
= TREE_CHAIN (list
);
1929 /* Return first list element whose BINFO_TYPE is ELEM.
1930 Return 0 if ELEM is not in LIST. */
1933 binfo_member (elem
, list
)
1938 if (elem
== BINFO_TYPE (list
))
1940 list
= TREE_CHAIN (list
);
1945 /* Return nonzero if ELEM is part of the chain CHAIN. */
1948 chain_member (elem
, chain
)
1955 chain
= TREE_CHAIN (chain
);
1961 /* Return nonzero if ELEM is equal to TREE_VALUE (CHAIN) for any piece of
1962 chain CHAIN. This and the next function are currently unused, but
1963 are retained for completeness. */
1966 chain_member_value (elem
, chain
)
1971 if (elem
== TREE_VALUE (chain
))
1973 chain
= TREE_CHAIN (chain
);
1979 /* Return nonzero if ELEM is equal to TREE_PURPOSE (CHAIN)
1980 for any piece of chain CHAIN. */
1983 chain_member_purpose (elem
, chain
)
1988 if (elem
== TREE_PURPOSE (chain
))
1990 chain
= TREE_CHAIN (chain
);
1996 /* Return the length of a chain of nodes chained through TREE_CHAIN.
1997 We expect a null pointer to mark the end of the chain.
1998 This is the Lisp primitive `length'. */
2005 register int len
= 0;
2007 for (tail
= t
; tail
; tail
= TREE_CHAIN (tail
))
2013 /* Returns the number of FIELD_DECLs in TYPE. */
2016 fields_length (type
)
2019 tree t
= TYPE_FIELDS (type
);
2022 for (; t
; t
= TREE_CHAIN (t
))
2023 if (TREE_CODE (t
) == FIELD_DECL
)
2029 /* Concatenate two chains of nodes (chained through TREE_CHAIN)
2030 by modifying the last node in chain 1 to point to chain 2.
2031 This is the Lisp primitive `nconc'. */
2041 #ifdef ENABLE_TREE_CHECKING
2045 for (t1
= op1
; TREE_CHAIN (t1
); t1
= TREE_CHAIN (t1
))
2047 TREE_CHAIN (t1
) = op2
;
2048 #ifdef ENABLE_TREE_CHECKING
2049 for (t2
= op2
; t2
; t2
= TREE_CHAIN (t2
))
2051 abort (); /* Circularity created. */
2058 /* Return the last node in a chain of nodes (chained through TREE_CHAIN). */
2062 register tree chain
;
2066 while ((next
= TREE_CHAIN (chain
)))
2071 /* Reverse the order of elements in the chain T,
2072 and return the new head of the chain (old last element). */
2078 register tree prev
= 0, decl
, next
;
2079 for (decl
= t
; decl
; decl
= next
)
2081 next
= TREE_CHAIN (decl
);
2082 TREE_CHAIN (decl
) = prev
;
2088 /* Given a chain CHAIN of tree nodes,
2089 construct and return a list of those nodes. */
2095 tree result
= NULL_TREE
;
2096 tree in_tail
= chain
;
2097 tree out_tail
= NULL_TREE
;
2101 tree next
= tree_cons (NULL_TREE
, in_tail
, NULL_TREE
);
2103 TREE_CHAIN (out_tail
) = next
;
2107 in_tail
= TREE_CHAIN (in_tail
);
2113 /* Return a newly created TREE_LIST node whose
2114 purpose and value fields are PARM and VALUE. */
2117 build_tree_list (parm
, value
)
2120 register tree t
= make_node (TREE_LIST
);
2121 TREE_PURPOSE (t
) = parm
;
2122 TREE_VALUE (t
) = value
;
2126 /* Similar, but build on the temp_decl_obstack. */
2129 build_decl_list (parm
, value
)
2133 register struct obstack
*ambient_obstack
= current_obstack
;
2135 current_obstack
= &temp_decl_obstack
;
2136 node
= build_tree_list (parm
, value
);
2137 current_obstack
= ambient_obstack
;
2141 /* Similar, but build on the expression_obstack. */
2144 build_expr_list (parm
, value
)
2148 register struct obstack
*ambient_obstack
= current_obstack
;
2150 current_obstack
= expression_obstack
;
2151 node
= build_tree_list (parm
, value
);
2152 current_obstack
= ambient_obstack
;
2156 /* Return a newly created TREE_LIST node whose
2157 purpose and value fields are PARM and VALUE
2158 and whose TREE_CHAIN is CHAIN. */
2161 tree_cons (purpose
, value
, chain
)
2162 tree purpose
, value
, chain
;
2167 node
= ggc_alloc_tree (sizeof (struct tree_list
));
2170 node
= (tree
) obstack_alloc (current_obstack
, sizeof (struct tree_list
));
2171 memset (node
, 0, sizeof (struct tree_common
));
2174 #ifdef GATHER_STATISTICS
2175 tree_node_counts
[(int) x_kind
]++;
2176 tree_node_sizes
[(int) x_kind
] += sizeof (struct tree_list
);
2179 TREE_SET_CODE (node
, TREE_LIST
);
2180 TREE_SET_PERMANENT (node
);
2182 TREE_CHAIN (node
) = chain
;
2183 TREE_PURPOSE (node
) = purpose
;
2184 TREE_VALUE (node
) = value
;
2188 /* Similar, but build on the temp_decl_obstack. */
2191 decl_tree_cons (purpose
, value
, chain
)
2192 tree purpose
, value
, chain
;
2195 register struct obstack
*ambient_obstack
= current_obstack
;
2197 current_obstack
= &temp_decl_obstack
;
2198 node
= tree_cons (purpose
, value
, chain
);
2199 current_obstack
= ambient_obstack
;
2203 /* Similar, but build on the expression_obstack. */
2206 expr_tree_cons (purpose
, value
, chain
)
2207 tree purpose
, value
, chain
;
2210 register struct obstack
*ambient_obstack
= current_obstack
;
2212 current_obstack
= expression_obstack
;
2213 node
= tree_cons (purpose
, value
, chain
);
2214 current_obstack
= ambient_obstack
;
2218 /* Same as `tree_cons' but make a permanent object. */
2221 perm_tree_cons (purpose
, value
, chain
)
2222 tree purpose
, value
, chain
;
2225 register struct obstack
*ambient_obstack
= current_obstack
;
2227 current_obstack
= &permanent_obstack
;
2228 node
= tree_cons (purpose
, value
, chain
);
2229 current_obstack
= ambient_obstack
;
2233 /* Same as `tree_cons', but make this node temporary, regardless. */
2236 temp_tree_cons (purpose
, value
, chain
)
2237 tree purpose
, value
, chain
;
2240 register struct obstack
*ambient_obstack
= current_obstack
;
2242 current_obstack
= &temporary_obstack
;
2243 node
= tree_cons (purpose
, value
, chain
);
2244 current_obstack
= ambient_obstack
;
2248 /* Same as `tree_cons', but save this node if the function's RTL is saved. */
2251 saveable_tree_cons (purpose
, value
, chain
)
2252 tree purpose
, value
, chain
;
2255 register struct obstack
*ambient_obstack
= current_obstack
;
2257 current_obstack
= saveable_obstack
;
2258 node
= tree_cons (purpose
, value
, chain
);
2259 current_obstack
= ambient_obstack
;
2263 /* Return the size nominally occupied by an object of type TYPE
2264 when it resides in memory. The value is measured in units of bytes,
2265 and its data type is that normally used for type sizes
2266 (which is the first type created by make_signed_type or
2267 make_unsigned_type). */
2270 size_in_bytes (type
)
2275 if (type
== error_mark_node
)
2276 return integer_zero_node
;
2278 type
= TYPE_MAIN_VARIANT (type
);
2279 t
= TYPE_SIZE_UNIT (type
);
2283 incomplete_type_error (NULL_TREE
, type
);
2284 return size_zero_node
;
2287 if (TREE_CODE (t
) == INTEGER_CST
)
2288 force_fit_type (t
, 0);
2293 /* Return the size of TYPE (in bytes) as a wide integer
2294 or return -1 if the size can vary or is larger than an integer. */
2297 int_size_in_bytes (type
)
2302 if (type
== error_mark_node
)
2305 type
= TYPE_MAIN_VARIANT (type
);
2306 t
= TYPE_SIZE_UNIT (type
);
2308 || TREE_CODE (t
) != INTEGER_CST
2309 || TREE_OVERFLOW (t
)
2310 || TREE_INT_CST_HIGH (t
) != 0
2311 /* If the result would appear negative, it's too big to represent. */
2312 || (HOST_WIDE_INT
) TREE_INT_CST_LOW (t
) < 0)
2315 return TREE_INT_CST_LOW (t
);
2318 /* Return the bit position of FIELD, in bits from the start of the record.
2319 This is a tree of type bitsizetype. */
2322 bit_position (field
)
2326 return bit_from_pos (DECL_FIELD_OFFSET (field
),
2327 DECL_FIELD_BIT_OFFSET (field
));
2330 /* Likewise, but return as an integer. Abort if it cannot be represented
2331 in that way (since it could be a signed value, we don't have the option
2332 of returning -1 like int_size_in_byte can. */
2335 int_bit_position (field
)
2338 return tree_low_cst (bit_position (field
), 0);
2341 /* Return the byte position of FIELD, in bytes from the start of the record.
2342 This is a tree of type sizetype. */
2345 byte_position (field
)
2348 return byte_from_pos (DECL_FIELD_OFFSET (field
),
2349 DECL_FIELD_BIT_OFFSET (field
));
2352 /* Likewise, but return as an integer. Abort if it cannot be represented
2353 in that way (since it could be a signed value, we don't have the option
2354 of returning -1 like int_size_in_byte can. */
2357 int_byte_position (field
)
2360 return tree_low_cst (byte_position (field
), 0);
2363 /* Return the strictest alignment, in bits, that T is known to have. */
2369 unsigned int align0
, align1
;
2371 switch (TREE_CODE (t
))
2373 case NOP_EXPR
: case CONVERT_EXPR
: case NON_LVALUE_EXPR
:
2374 /* If we have conversions, we know that the alignment of the
2375 object must meet each of the alignments of the types. */
2376 align0
= expr_align (TREE_OPERAND (t
, 0));
2377 align1
= TYPE_ALIGN (TREE_TYPE (t
));
2378 return MAX (align0
, align1
);
2380 case SAVE_EXPR
: case COMPOUND_EXPR
: case MODIFY_EXPR
:
2381 case INIT_EXPR
: case TARGET_EXPR
: case WITH_CLEANUP_EXPR
:
2382 case WITH_RECORD_EXPR
: case CLEANUP_POINT_EXPR
: case UNSAVE_EXPR
:
2383 /* These don't change the alignment of an object. */
2384 return expr_align (TREE_OPERAND (t
, 0));
2387 /* The best we can do is say that the alignment is the least aligned
2389 align0
= expr_align (TREE_OPERAND (t
, 1));
2390 align1
= expr_align (TREE_OPERAND (t
, 2));
2391 return MIN (align0
, align1
);
2393 case LABEL_DECL
: case CONST_DECL
:
2394 case VAR_DECL
: case PARM_DECL
: case RESULT_DECL
:
2395 if (DECL_ALIGN (t
) != 0)
2396 return DECL_ALIGN (t
);
2400 return FUNCTION_BOUNDARY
;
2406 /* Otherwise take the alignment from that of the type. */
2407 return TYPE_ALIGN (TREE_TYPE (t
));
2410 /* Return, as a tree node, the number of elements for TYPE (which is an
2411 ARRAY_TYPE) minus one. This counts only elements of the top array. */
2414 array_type_nelts (type
)
2417 tree index_type
, min
, max
;
2419 /* If they did it with unspecified bounds, then we should have already
2420 given an error about it before we got here. */
2421 if (! TYPE_DOMAIN (type
))
2422 return error_mark_node
;
2424 index_type
= TYPE_DOMAIN (type
);
2425 min
= TYPE_MIN_VALUE (index_type
);
2426 max
= TYPE_MAX_VALUE (index_type
);
2428 return (integer_zerop (min
)
2430 : fold (build (MINUS_EXPR
, TREE_TYPE (max
), max
, min
)));
2433 /* Return nonzero if arg is static -- a reference to an object in
2434 static storage. This is not the same as the C meaning of `static'. */
2440 switch (TREE_CODE (arg
))
2443 /* Nested functions aren't static, since taking their address
2444 involves a trampoline. */
2445 return (decl_function_context (arg
) == 0 || DECL_NO_STATIC_CHAIN (arg
))
2446 && ! DECL_NON_ADDR_CONST_P (arg
);
2449 return (TREE_STATIC (arg
) || DECL_EXTERNAL (arg
))
2450 && ! DECL_NON_ADDR_CONST_P (arg
);
2453 return TREE_STATIC (arg
);
2458 /* If we are referencing a bitfield, we can't evaluate an
2459 ADDR_EXPR at compile time and so it isn't a constant. */
2461 return (! DECL_BIT_FIELD (TREE_OPERAND (arg
, 1))
2462 && staticp (TREE_OPERAND (arg
, 0)));
2468 /* This case is technically correct, but results in setting
2469 TREE_CONSTANT on ADDR_EXPRs that cannot be evaluated at
2472 return TREE_CONSTANT (TREE_OPERAND (arg
, 0));
2476 if (TREE_CODE (TYPE_SIZE (TREE_TYPE (arg
))) == INTEGER_CST
2477 && TREE_CODE (TREE_OPERAND (arg
, 1)) == INTEGER_CST
)
2478 return staticp (TREE_OPERAND (arg
, 0));
2485 /* Wrap a SAVE_EXPR around EXPR, if appropriate.
2486 Do this to any expression which may be used in more than one place,
2487 but must be evaluated only once.
2489 Normally, expand_expr would reevaluate the expression each time.
2490 Calling save_expr produces something that is evaluated and recorded
2491 the first time expand_expr is called on it. Subsequent calls to
2492 expand_expr just reuse the recorded value.
2494 The call to expand_expr that generates code that actually computes
2495 the value is the first call *at compile time*. Subsequent calls
2496 *at compile time* generate code to use the saved value.
2497 This produces correct result provided that *at run time* control
2498 always flows through the insns made by the first expand_expr
2499 before reaching the other places where the save_expr was evaluated.
2500 You, the caller of save_expr, must make sure this is so.
2502 Constants, and certain read-only nodes, are returned with no
2503 SAVE_EXPR because that is safe. Expressions containing placeholders
2504 are not touched; see tree.def for an explanation of what these
2511 register tree t
= fold (expr
);
2513 /* We don't care about whether this can be used as an lvalue in this
2515 while (TREE_CODE (t
) == NON_LVALUE_EXPR
)
2516 t
= TREE_OPERAND (t
, 0);
2518 /* If the tree evaluates to a constant, then we don't want to hide that
2519 fact (i.e. this allows further folding, and direct checks for constants).
2520 However, a read-only object that has side effects cannot be bypassed.
2521 Since it is no problem to reevaluate literals, we just return the
2524 if (TREE_CONSTANT (t
) || (TREE_READONLY (t
) && ! TREE_SIDE_EFFECTS (t
))
2525 || TREE_CODE (t
) == SAVE_EXPR
|| TREE_CODE (t
) == ERROR_MARK
)
2528 /* If T contains a PLACEHOLDER_EXPR, we must evaluate it each time, since
2529 it means that the size or offset of some field of an object depends on
2530 the value within another field.
2532 Note that it must not be the case that T contains both a PLACEHOLDER_EXPR
2533 and some variable since it would then need to be both evaluated once and
2534 evaluated more than once. Front-ends must assure this case cannot
2535 happen by surrounding any such subexpressions in their own SAVE_EXPR
2536 and forcing evaluation at the proper time. */
2537 if (contains_placeholder_p (t
))
2540 t
= build (SAVE_EXPR
, TREE_TYPE (expr
), t
, current_function_decl
, NULL_TREE
);
2542 /* This expression might be placed ahead of a jump to ensure that the
2543 value was computed on both sides of the jump. So make sure it isn't
2544 eliminated as dead. */
2545 TREE_SIDE_EFFECTS (t
) = 1;
2549 /* Arrange for an expression to be expanded multiple independent
2550 times. This is useful for cleanup actions, as the backend can
2551 expand them multiple times in different places. */
2559 /* If this is already protected, no sense in protecting it again. */
2560 if (TREE_CODE (expr
) == UNSAVE_EXPR
)
2563 t
= build1 (UNSAVE_EXPR
, TREE_TYPE (expr
), expr
);
2564 TREE_SIDE_EFFECTS (t
) = TREE_SIDE_EFFECTS (expr
);
2568 /* Returns the index of the first non-tree operand for CODE, or the number
2569 of operands if all are trees. */
2573 enum tree_code code
;
2579 case GOTO_SUBROUTINE_EXPR
:
2584 case WITH_CLEANUP_EXPR
:
2585 /* Should be defined to be 2. */
2587 case METHOD_CALL_EXPR
:
2590 return tree_code_length
[(int) code
];
2594 /* Perform any modifications to EXPR required when it is unsaved. Does
2595 not recurse into EXPR's subtrees. */
2598 unsave_expr_1 (expr
)
2601 switch (TREE_CODE (expr
))
2604 if (! SAVE_EXPR_PERSISTENT_P (expr
))
2605 SAVE_EXPR_RTL (expr
) = 0;
2609 /* Don't mess with a TARGET_EXPR that hasn't been expanded.
2610 It's OK for this to happen if it was part of a subtree that
2611 isn't immediately expanded, such as operand 2 of another
2613 if (TREE_OPERAND (expr
, 1))
2616 TREE_OPERAND (expr
, 1) = TREE_OPERAND (expr
, 3);
2617 TREE_OPERAND (expr
, 3) = NULL_TREE
;
2621 /* I don't yet know how to emit a sequence multiple times. */
2622 if (RTL_EXPR_SEQUENCE (expr
) != 0)
2627 CALL_EXPR_RTL (expr
) = 0;
2631 if (lang_unsave_expr_now
!= 0)
2632 (*lang_unsave_expr_now
) (expr
);
2637 /* Helper function for unsave_expr_now. */
2640 unsave_expr_now_r (expr
)
2643 enum tree_code code
;
2645 /* There's nothing to do for NULL_TREE. */
2649 unsave_expr_1 (expr
);
2651 code
= TREE_CODE (expr
);
2652 switch (TREE_CODE_CLASS (code
))
2654 case 'c': /* a constant */
2655 case 't': /* a type node */
2656 case 'd': /* A decl node */
2657 case 'b': /* A block node */
2660 case 'x': /* miscellaneous: e.g., identifier, TREE_LIST or ERROR_MARK. */
2661 if (code
== TREE_LIST
)
2663 unsave_expr_now_r (TREE_VALUE (expr
));
2664 unsave_expr_now_r (TREE_CHAIN (expr
));
2668 case 'e': /* an expression */
2669 case 'r': /* a reference */
2670 case 's': /* an expression with side effects */
2671 case '<': /* a comparison expression */
2672 case '2': /* a binary arithmetic expression */
2673 case '1': /* a unary arithmetic expression */
2677 for (i
= first_rtl_op (code
) - 1; i
>= 0; i
--)
2678 unsave_expr_now_r (TREE_OPERAND (expr
, i
));
2687 /* Modify a tree in place so that all the evaluate only once things
2688 are cleared out. Return the EXPR given. */
2691 unsave_expr_now (expr
)
2694 if (lang_unsave
!= 0)
2695 (*lang_unsave
) (&expr
);
2697 unsave_expr_now_r (expr
);
2702 /* Return 0 if it is safe to evaluate EXPR multiple times,
2703 return 1 if it is safe if EXPR is unsaved afterward, or
2704 return 2 if it is completely unsafe.
2706 This assumes that CALL_EXPRs and TARGET_EXPRs are never replicated in
2707 an expression tree, so that it safe to unsave them and the surrounding
2708 context will be correct.
2710 SAVE_EXPRs basically *only* appear replicated in an expression tree,
2711 occasionally across the whole of a function. It is therefore only
2712 safe to unsave a SAVE_EXPR if you know that all occurrences appear
2713 below the UNSAVE_EXPR.
2715 RTL_EXPRs consume their rtl during evaluation. It is therefore
2716 never possible to unsave them. */
2719 unsafe_for_reeval (expr
)
2723 enum tree_code code
;
2728 if (expr
== NULL_TREE
)
2731 code
= TREE_CODE (expr
);
2732 first_rtl
= first_rtl_op (code
);
2741 for (exp
= expr
; exp
!= 0; exp
= TREE_CHAIN (exp
))
2743 tmp
= unsafe_for_reeval (TREE_VALUE (exp
));
2744 unsafeness
= MAX (tmp
, unsafeness
);
2750 tmp
= unsafe_for_reeval (TREE_OPERAND (expr
, 1));
2751 return MAX (tmp
, 1);
2758 /* ??? Add a lang hook if it becomes necessary. */
2762 switch (TREE_CODE_CLASS (code
))
2764 case 'c': /* a constant */
2765 case 't': /* a type node */
2766 case 'x': /* something random, like an identifier or an ERROR_MARK. */
2767 case 'd': /* A decl node */
2768 case 'b': /* A block node */
2771 case 'e': /* an expression */
2772 case 'r': /* a reference */
2773 case 's': /* an expression with side effects */
2774 case '<': /* a comparison expression */
2775 case '2': /* a binary arithmetic expression */
2776 case '1': /* a unary arithmetic expression */
2777 for (i
= first_rtl
- 1; i
>= 0; i
--)
2779 tmp
= unsafe_for_reeval (TREE_OPERAND (expr
, i
));
2780 unsafeness
= MAX (tmp
, unsafeness
);
2790 /* Return 1 if EXP contains a PLACEHOLDER_EXPR; i.e., if it represents a size
2791 or offset that depends on a field within a record. */
2794 contains_placeholder_p (exp
)
2797 register enum tree_code code
= TREE_CODE (exp
);
2800 /* If we have a WITH_RECORD_EXPR, it "cancels" any PLACEHOLDER_EXPR
2801 in it since it is supplying a value for it. */
2802 if (code
== WITH_RECORD_EXPR
)
2804 else if (code
== PLACEHOLDER_EXPR
)
2807 switch (TREE_CODE_CLASS (code
))
2810 /* Don't look at any PLACEHOLDER_EXPRs that might be in index or bit
2811 position computations since they will be converted into a
2812 WITH_RECORD_EXPR involving the reference, which will assume
2813 here will be valid. */
2814 return contains_placeholder_p (TREE_OPERAND (exp
, 0));
2817 if (code
== TREE_LIST
)
2818 return (contains_placeholder_p (TREE_VALUE (exp
))
2819 || (TREE_CHAIN (exp
) != 0
2820 && contains_placeholder_p (TREE_CHAIN (exp
))));
2829 /* Ignoring the first operand isn't quite right, but works best. */
2830 return contains_placeholder_p (TREE_OPERAND (exp
, 1));
2837 return (contains_placeholder_p (TREE_OPERAND (exp
, 0))
2838 || contains_placeholder_p (TREE_OPERAND (exp
, 1))
2839 || contains_placeholder_p (TREE_OPERAND (exp
, 2)));
2842 /* If we already know this doesn't have a placeholder, don't
2844 if (SAVE_EXPR_NOPLACEHOLDER (exp
) || SAVE_EXPR_RTL (exp
) != 0)
2847 SAVE_EXPR_NOPLACEHOLDER (exp
) = 1;
2848 result
= contains_placeholder_p (TREE_OPERAND (exp
, 0));
2850 SAVE_EXPR_NOPLACEHOLDER (exp
) = 0;
2855 return (TREE_OPERAND (exp
, 1) != 0
2856 && contains_placeholder_p (TREE_OPERAND (exp
, 1)));
2862 switch (tree_code_length
[(int) code
])
2865 return contains_placeholder_p (TREE_OPERAND (exp
, 0));
2867 return (contains_placeholder_p (TREE_OPERAND (exp
, 0))
2868 || contains_placeholder_p (TREE_OPERAND (exp
, 1)));
2879 /* Return 1 if EXP contains any expressions that produce cleanups for an
2880 outer scope to deal with. Used by fold. */
2888 if (! TREE_SIDE_EFFECTS (exp
))
2891 switch (TREE_CODE (exp
))
2894 case GOTO_SUBROUTINE_EXPR
:
2895 case WITH_CLEANUP_EXPR
:
2898 case CLEANUP_POINT_EXPR
:
2902 for (exp
= TREE_OPERAND (exp
, 1); exp
; exp
= TREE_CHAIN (exp
))
2904 cmp
= has_cleanups (TREE_VALUE (exp
));
2914 /* This general rule works for most tree codes. All exceptions should be
2915 handled above. If this is a language-specific tree code, we can't
2916 trust what might be in the operand, so say we don't know
2918 if ((int) TREE_CODE (exp
) >= (int) LAST_AND_UNUSED_TREE_CODE
)
2921 nops
= first_rtl_op (TREE_CODE (exp
));
2922 for (i
= 0; i
< nops
; i
++)
2923 if (TREE_OPERAND (exp
, i
) != 0)
2925 int type
= TREE_CODE_CLASS (TREE_CODE (TREE_OPERAND (exp
, i
)));
2926 if (type
== 'e' || type
== '<' || type
== '1' || type
== '2'
2927 || type
== 'r' || type
== 's')
2929 cmp
= has_cleanups (TREE_OPERAND (exp
, i
));
2938 /* Given a tree EXP, a FIELD_DECL F, and a replacement value R,
2939 return a tree with all occurrences of references to F in a
2940 PLACEHOLDER_EXPR replaced by R. Note that we assume here that EXP
2941 contains only arithmetic expressions or a CALL_EXPR with a
2942 PLACEHOLDER_EXPR occurring only in its arglist. */
2945 substitute_in_expr (exp
, f
, r
)
2950 enum tree_code code
= TREE_CODE (exp
);
2955 switch (TREE_CODE_CLASS (code
))
2962 if (code
== PLACEHOLDER_EXPR
)
2964 else if (code
== TREE_LIST
)
2966 op0
= (TREE_CHAIN (exp
) == 0
2967 ? 0 : substitute_in_expr (TREE_CHAIN (exp
), f
, r
));
2968 op1
= substitute_in_expr (TREE_VALUE (exp
), f
, r
);
2969 if (op0
== TREE_CHAIN (exp
) && op1
== TREE_VALUE (exp
))
2972 return tree_cons (TREE_PURPOSE (exp
), op1
, op0
);
2981 switch (tree_code_length
[(int) code
])
2984 op0
= substitute_in_expr (TREE_OPERAND (exp
, 0), f
, r
);
2985 if (op0
== TREE_OPERAND (exp
, 0))
2988 new = fold (build1 (code
, TREE_TYPE (exp
), op0
));
2992 /* An RTL_EXPR cannot contain a PLACEHOLDER_EXPR; a CONSTRUCTOR
2993 could, but we don't support it. */
2994 if (code
== RTL_EXPR
)
2996 else if (code
== CONSTRUCTOR
)
2999 op0
= substitute_in_expr (TREE_OPERAND (exp
, 0), f
, r
);
3000 op1
= substitute_in_expr (TREE_OPERAND (exp
, 1), f
, r
);
3001 if (op0
== TREE_OPERAND (exp
, 0) && op1
== TREE_OPERAND (exp
, 1))
3004 new = fold (build (code
, TREE_TYPE (exp
), op0
, op1
));
3008 /* It cannot be that anything inside a SAVE_EXPR contains a
3009 PLACEHOLDER_EXPR. */
3010 if (code
== SAVE_EXPR
)
3013 else if (code
== CALL_EXPR
)
3015 op1
= substitute_in_expr (TREE_OPERAND (exp
, 1), f
, r
);
3016 if (op1
== TREE_OPERAND (exp
, 1))
3019 return build (code
, TREE_TYPE (exp
),
3020 TREE_OPERAND (exp
, 0), op1
, NULL_TREE
);
3023 else if (code
!= COND_EXPR
)
3026 op0
= substitute_in_expr (TREE_OPERAND (exp
, 0), f
, r
);
3027 op1
= substitute_in_expr (TREE_OPERAND (exp
, 1), f
, r
);
3028 op2
= substitute_in_expr (TREE_OPERAND (exp
, 2), f
, r
);
3029 if (op0
== TREE_OPERAND (exp
, 0) && op1
== TREE_OPERAND (exp
, 1)
3030 && op2
== TREE_OPERAND (exp
, 2))
3033 new = fold (build (code
, TREE_TYPE (exp
), op0
, op1
, op2
));
3046 /* If this expression is getting a value from a PLACEHOLDER_EXPR
3047 and it is the right field, replace it with R. */
3048 for (inner
= TREE_OPERAND (exp
, 0);
3049 TREE_CODE_CLASS (TREE_CODE (inner
)) == 'r';
3050 inner
= TREE_OPERAND (inner
, 0))
3052 if (TREE_CODE (inner
) == PLACEHOLDER_EXPR
3053 && TREE_OPERAND (exp
, 1) == f
)
3056 /* If this expression hasn't been completed let, leave it
3058 if (TREE_CODE (inner
) == PLACEHOLDER_EXPR
3059 && TREE_TYPE (inner
) == 0)
3062 op0
= substitute_in_expr (TREE_OPERAND (exp
, 0), f
, r
);
3063 if (op0
== TREE_OPERAND (exp
, 0))
3066 new = fold (build (code
, TREE_TYPE (exp
), op0
,
3067 TREE_OPERAND (exp
, 1)));
3071 op0
= substitute_in_expr (TREE_OPERAND (exp
, 0), f
, r
);
3072 op1
= substitute_in_expr (TREE_OPERAND (exp
, 1), f
, r
);
3073 op2
= substitute_in_expr (TREE_OPERAND (exp
, 2), f
, r
);
3074 if (op0
== TREE_OPERAND (exp
, 0) && op1
== TREE_OPERAND (exp
, 1)
3075 && op2
== TREE_OPERAND (exp
, 2))
3078 new = fold (build (code
, TREE_TYPE (exp
), op0
, op1
, op2
));
3083 op0
= substitute_in_expr (TREE_OPERAND (exp
, 0), f
, r
);
3084 if (op0
== TREE_OPERAND (exp
, 0))
3087 new = fold (build1 (code
, TREE_TYPE (exp
), op0
));
3099 TREE_READONLY (new) = TREE_READONLY (exp
);
3103 /* Stabilize a reference so that we can use it any number of times
3104 without causing its operands to be evaluated more than once.
3105 Returns the stabilized reference. This works by means of save_expr,
3106 so see the caveats in the comments about save_expr.
3108 Also allows conversion expressions whose operands are references.
3109 Any other kind of expression is returned unchanged. */
3112 stabilize_reference (ref
)
3115 register tree result
;
3116 register enum tree_code code
= TREE_CODE (ref
);
3123 /* No action is needed in this case. */
3129 case FIX_TRUNC_EXPR
:
3130 case FIX_FLOOR_EXPR
:
3131 case FIX_ROUND_EXPR
:
3133 result
= build_nt (code
, stabilize_reference (TREE_OPERAND (ref
, 0)));
3137 result
= build_nt (INDIRECT_REF
,
3138 stabilize_reference_1 (TREE_OPERAND (ref
, 0)));
3142 result
= build_nt (COMPONENT_REF
,
3143 stabilize_reference (TREE_OPERAND (ref
, 0)),
3144 TREE_OPERAND (ref
, 1));
3148 result
= build_nt (BIT_FIELD_REF
,
3149 stabilize_reference (TREE_OPERAND (ref
, 0)),
3150 stabilize_reference_1 (TREE_OPERAND (ref
, 1)),
3151 stabilize_reference_1 (TREE_OPERAND (ref
, 2)));
3155 result
= build_nt (ARRAY_REF
,
3156 stabilize_reference (TREE_OPERAND (ref
, 0)),
3157 stabilize_reference_1 (TREE_OPERAND (ref
, 1)));
3161 /* We cannot wrap the first expression in a SAVE_EXPR, as then
3162 it wouldn't be ignored. This matters when dealing with
3164 return stabilize_reference_1 (ref
);
3167 result
= build1 (INDIRECT_REF
, TREE_TYPE (ref
),
3168 save_expr (build1 (ADDR_EXPR
,
3169 build_pointer_type (TREE_TYPE (ref
)),
3174 /* If arg isn't a kind of lvalue we recognize, make no change.
3175 Caller should recognize the error for an invalid lvalue. */
3180 return error_mark_node
;
3183 TREE_TYPE (result
) = TREE_TYPE (ref
);
3184 TREE_READONLY (result
) = TREE_READONLY (ref
);
3185 TREE_SIDE_EFFECTS (result
) = TREE_SIDE_EFFECTS (ref
);
3186 TREE_THIS_VOLATILE (result
) = TREE_THIS_VOLATILE (ref
);
3191 /* Subroutine of stabilize_reference; this is called for subtrees of
3192 references. Any expression with side-effects must be put in a SAVE_EXPR
3193 to ensure that it is only evaluated once.
3195 We don't put SAVE_EXPR nodes around everything, because assigning very
3196 simple expressions to temporaries causes us to miss good opportunities
3197 for optimizations. Among other things, the opportunity to fold in the
3198 addition of a constant into an addressing mode often gets lost, e.g.
3199 "y[i+1] += x;". In general, we take the approach that we should not make
3200 an assignment unless we are forced into it - i.e., that any non-side effect
3201 operator should be allowed, and that cse should take care of coalescing
3202 multiple utterances of the same expression should that prove fruitful. */
3205 stabilize_reference_1 (e
)
3208 register tree result
;
3209 register enum tree_code code
= TREE_CODE (e
);
3211 /* We cannot ignore const expressions because it might be a reference
3212 to a const array but whose index contains side-effects. But we can
3213 ignore things that are actual constant or that already have been
3214 handled by this function. */
3216 if (TREE_CONSTANT (e
) || code
== SAVE_EXPR
)
3219 switch (TREE_CODE_CLASS (code
))
3229 /* If the expression has side-effects, then encase it in a SAVE_EXPR
3230 so that it will only be evaluated once. */
3231 /* The reference (r) and comparison (<) classes could be handled as
3232 below, but it is generally faster to only evaluate them once. */
3233 if (TREE_SIDE_EFFECTS (e
))
3234 return save_expr (e
);
3238 /* Constants need no processing. In fact, we should never reach
3243 /* Division is slow and tends to be compiled with jumps,
3244 especially the division by powers of 2 that is often
3245 found inside of an array reference. So do it just once. */
3246 if (code
== TRUNC_DIV_EXPR
|| code
== TRUNC_MOD_EXPR
3247 || code
== FLOOR_DIV_EXPR
|| code
== FLOOR_MOD_EXPR
3248 || code
== CEIL_DIV_EXPR
|| code
== CEIL_MOD_EXPR
3249 || code
== ROUND_DIV_EXPR
|| code
== ROUND_MOD_EXPR
)
3250 return save_expr (e
);
3251 /* Recursively stabilize each operand. */
3252 result
= build_nt (code
, stabilize_reference_1 (TREE_OPERAND (e
, 0)),
3253 stabilize_reference_1 (TREE_OPERAND (e
, 1)));
3257 /* Recursively stabilize each operand. */
3258 result
= build_nt (code
, stabilize_reference_1 (TREE_OPERAND (e
, 0)));
3265 TREE_TYPE (result
) = TREE_TYPE (e
);
3266 TREE_READONLY (result
) = TREE_READONLY (e
);
3267 TREE_SIDE_EFFECTS (result
) = TREE_SIDE_EFFECTS (e
);
3268 TREE_THIS_VOLATILE (result
) = TREE_THIS_VOLATILE (e
);
3273 /* Low-level constructors for expressions. */
3275 /* Build an expression of code CODE, data type TYPE,
3276 and operands as specified by the arguments ARG1 and following arguments.
3277 Expressions and reference nodes can be created this way.
3278 Constants, decls, types and misc nodes cannot be. */
3281 build
VPARAMS ((enum tree_code code
, tree tt
, ...))
3283 #ifndef ANSI_PROTOTYPES
3284 enum tree_code code
;
3289 register int length
;
3295 #ifndef ANSI_PROTOTYPES
3296 code
= va_arg (p
, enum tree_code
);
3297 tt
= va_arg (p
, tree
);
3300 t
= make_node (code
);
3301 length
= tree_code_length
[(int) code
];
3304 /* Below, we automatically set TREE_SIDE_EFFECTS and TREE_RAISED for
3305 the result based on those same flags for the arguments. But, if
3306 the arguments aren't really even `tree' expressions, we shouldn't
3307 be trying to do this. */
3308 fro
= first_rtl_op (code
);
3312 /* This is equivalent to the loop below, but faster. */
3313 register tree arg0
= va_arg (p
, tree
);
3314 register tree arg1
= va_arg (p
, tree
);
3315 TREE_OPERAND (t
, 0) = arg0
;
3316 TREE_OPERAND (t
, 1) = arg1
;
3317 if (arg0
&& fro
> 0)
3319 if (TREE_SIDE_EFFECTS (arg0
))
3320 TREE_SIDE_EFFECTS (t
) = 1;
3322 if (arg1
&& fro
> 1)
3324 if (TREE_SIDE_EFFECTS (arg1
))
3325 TREE_SIDE_EFFECTS (t
) = 1;
3328 else if (length
== 1)
3330 register tree arg0
= va_arg (p
, tree
);
3332 /* Call build1 for this! */
3333 if (TREE_CODE_CLASS (code
) != 's')
3335 TREE_OPERAND (t
, 0) = arg0
;
3338 if (arg0
&& TREE_SIDE_EFFECTS (arg0
))
3339 TREE_SIDE_EFFECTS (t
) = 1;
3344 for (i
= 0; i
< length
; i
++)
3346 register tree operand
= va_arg (p
, tree
);
3347 TREE_OPERAND (t
, i
) = operand
;
3348 if (operand
&& fro
> i
)
3350 if (TREE_SIDE_EFFECTS (operand
))
3351 TREE_SIDE_EFFECTS (t
) = 1;
3359 /* Same as above, but only builds for unary operators.
3360 Saves lions share of calls to `build'; cuts down use
3361 of varargs, which is expensive for RISC machines. */
3364 build1 (code
, type
, node
)
3365 enum tree_code code
;
3369 register struct obstack
*obstack
= expression_obstack
;
3370 register int length
;
3371 #ifdef GATHER_STATISTICS
3372 register tree_node_kind kind
;
3376 #ifdef GATHER_STATISTICS
3377 if (TREE_CODE_CLASS (code
) == 'r')
3383 length
= sizeof (struct tree_exp
);
3386 t
= ggc_alloc_tree (length
);
3389 t
= (tree
) obstack_alloc (obstack
, length
);
3390 memset ((PTR
) t
, 0, length
);
3393 #ifdef GATHER_STATISTICS
3394 tree_node_counts
[(int)kind
]++;
3395 tree_node_sizes
[(int)kind
] += length
;
3398 TREE_TYPE (t
) = type
;
3399 TREE_SET_CODE (t
, code
);
3400 TREE_SET_PERMANENT (t
);
3402 TREE_OPERAND (t
, 0) = node
;
3403 if (node
&& first_rtl_op (code
) != 0 && TREE_SIDE_EFFECTS (node
))
3404 TREE_SIDE_EFFECTS (t
) = 1;
3412 case PREDECREMENT_EXPR
:
3413 case PREINCREMENT_EXPR
:
3414 case POSTDECREMENT_EXPR
:
3415 case POSTINCREMENT_EXPR
:
3416 /* All of these have side-effects, no matter what their
3418 TREE_SIDE_EFFECTS (t
) = 1;
3428 /* Similar except don't specify the TREE_TYPE
3429 and leave the TREE_SIDE_EFFECTS as 0.
3430 It is permissible for arguments to be null,
3431 or even garbage if their values do not matter. */
3434 build_nt
VPARAMS ((enum tree_code code
, ...))
3436 #ifndef ANSI_PROTOTYPES
3437 enum tree_code code
;
3441 register int length
;
3446 #ifndef ANSI_PROTOTYPES
3447 code
= va_arg (p
, enum tree_code
);
3450 t
= make_node (code
);
3451 length
= tree_code_length
[(int) code
];
3453 for (i
= 0; i
< length
; i
++)
3454 TREE_OPERAND (t
, i
) = va_arg (p
, tree
);
3460 /* Similar to `build_nt', except we build
3461 on the temp_decl_obstack, regardless. */
3464 build_parse_node
VPARAMS ((enum tree_code code
, ...))
3466 #ifndef ANSI_PROTOTYPES
3467 enum tree_code code
;
3469 register struct obstack
*ambient_obstack
= expression_obstack
;
3472 register int length
;
3477 #ifndef ANSI_PROTOTYPES
3478 code
= va_arg (p
, enum tree_code
);
3481 expression_obstack
= &temp_decl_obstack
;
3483 t
= make_node (code
);
3484 length
= tree_code_length
[(int) code
];
3486 for (i
= 0; i
< length
; i
++)
3487 TREE_OPERAND (t
, i
) = va_arg (p
, tree
);
3490 expression_obstack
= ambient_obstack
;
3495 /* Commented out because this wants to be done very
3496 differently. See cp-lex.c. */
3498 build_op_identifier (op1
, op2
)
3501 register tree t
= make_node (OP_IDENTIFIER
);
3502 TREE_PURPOSE (t
) = op1
;
3503 TREE_VALUE (t
) = op2
;
3508 /* Create a DECL_... node of code CODE, name NAME and data type TYPE.
3509 We do NOT enter this node in any sort of symbol table.
3511 layout_decl is used to set up the decl's storage layout.
3512 Other slots are initialized to 0 or null pointers. */
3515 build_decl (code
, name
, type
)
3516 enum tree_code code
;
3521 t
= make_node (code
);
3523 /* if (type == error_mark_node)
3524 type = integer_type_node; */
3525 /* That is not done, deliberately, so that having error_mark_node
3526 as the type can suppress useless errors in the use of this variable. */
3528 DECL_NAME (t
) = name
;
3529 DECL_ASSEMBLER_NAME (t
) = name
;
3530 TREE_TYPE (t
) = type
;
3532 if (code
== VAR_DECL
|| code
== PARM_DECL
|| code
== RESULT_DECL
)
3534 else if (code
== FUNCTION_DECL
)
3535 DECL_MODE (t
) = FUNCTION_MODE
;
3540 /* BLOCK nodes are used to represent the structure of binding contours
3541 and declarations, once those contours have been exited and their contents
3542 compiled. This information is used for outputting debugging info. */
3545 build_block (vars
, tags
, subblocks
, supercontext
, chain
)
3546 tree vars
, tags ATTRIBUTE_UNUSED
, subblocks
, supercontext
, chain
;
3548 register tree block
= make_node (BLOCK
);
3550 BLOCK_VARS (block
) = vars
;
3551 BLOCK_SUBBLOCKS (block
) = subblocks
;
3552 BLOCK_SUPERCONTEXT (block
) = supercontext
;
3553 BLOCK_CHAIN (block
) = chain
;
3557 /* EXPR_WITH_FILE_LOCATION are used to keep track of the exact
3558 location where an expression or an identifier were encountered. It
3559 is necessary for languages where the frontend parser will handle
3560 recursively more than one file (Java is one of them). */
3563 build_expr_wfl (node
, file
, line
, col
)
3568 static const char *last_file
= 0;
3569 static tree last_filenode
= NULL_TREE
;
3570 register tree wfl
= make_node (EXPR_WITH_FILE_LOCATION
);
3572 EXPR_WFL_NODE (wfl
) = node
;
3573 EXPR_WFL_SET_LINECOL (wfl
, line
, col
);
3574 if (file
!= last_file
)
3577 last_filenode
= file
? get_identifier (file
) : NULL_TREE
;
3580 EXPR_WFL_FILENAME_NODE (wfl
) = last_filenode
;
3583 TREE_SIDE_EFFECTS (wfl
) = TREE_SIDE_EFFECTS (node
);
3584 TREE_TYPE (wfl
) = TREE_TYPE (node
);
3590 /* Return a declaration like DDECL except that its DECL_MACHINE_ATTRIBUTE
3594 build_decl_attribute_variant (ddecl
, attribute
)
3595 tree ddecl
, attribute
;
3597 DECL_MACHINE_ATTRIBUTES (ddecl
) = attribute
;
3601 /* Return a type like TTYPE except that its TYPE_ATTRIBUTE
3604 Record such modified types already made so we don't make duplicates. */
3607 build_type_attribute_variant (ttype
, attribute
)
3608 tree ttype
, attribute
;
3610 if ( ! attribute_list_equal (TYPE_ATTRIBUTES (ttype
), attribute
))
3612 unsigned int hashcode
;
3615 push_obstacks (TYPE_OBSTACK (ttype
), TYPE_OBSTACK (ttype
));
3616 ntype
= copy_node (ttype
);
3618 TYPE_POINTER_TO (ntype
) = 0;
3619 TYPE_REFERENCE_TO (ntype
) = 0;
3620 TYPE_ATTRIBUTES (ntype
) = attribute
;
3622 /* Create a new main variant of TYPE. */
3623 TYPE_MAIN_VARIANT (ntype
) = ntype
;
3624 TYPE_NEXT_VARIANT (ntype
) = 0;
3625 set_type_quals (ntype
, TYPE_UNQUALIFIED
);
3627 hashcode
= (TYPE_HASH (TREE_CODE (ntype
))
3628 + TYPE_HASH (TREE_TYPE (ntype
))
3629 + attribute_hash_list (attribute
));
3631 switch (TREE_CODE (ntype
))
3634 hashcode
+= TYPE_HASH (TYPE_ARG_TYPES (ntype
));
3637 hashcode
+= TYPE_HASH (TYPE_DOMAIN (ntype
));
3640 hashcode
+= TYPE_HASH (TYPE_MAX_VALUE (ntype
));
3643 hashcode
+= TYPE_HASH (TYPE_PRECISION (ntype
));
3649 ntype
= type_hash_canon (hashcode
, ntype
);
3650 ttype
= build_qualified_type (ntype
, TYPE_QUALS (ttype
));
3657 /* Return a 1 if ATTR_NAME and ATTR_ARGS is valid for either declaration DECL
3658 or type TYPE and 0 otherwise. Validity is determined the configuration
3659 macros VALID_MACHINE_DECL_ATTRIBUTE and VALID_MACHINE_TYPE_ATTRIBUTE. */
3662 valid_machine_attribute (attr_name
, attr_args
, decl
, type
)
3664 tree attr_args ATTRIBUTE_UNUSED
;
3665 tree decl ATTRIBUTE_UNUSED
;
3666 tree type ATTRIBUTE_UNUSED
;
3669 #ifdef VALID_MACHINE_DECL_ATTRIBUTE
3670 tree decl_attr_list
= decl
!= 0 ? DECL_MACHINE_ATTRIBUTES (decl
) : 0;
3672 #ifdef VALID_MACHINE_TYPE_ATTRIBUTE
3673 tree type_attr_list
= TYPE_ATTRIBUTES (type
);
3676 if (TREE_CODE (attr_name
) != IDENTIFIER_NODE
)
3679 #ifdef VALID_MACHINE_DECL_ATTRIBUTE
3681 && VALID_MACHINE_DECL_ATTRIBUTE (decl
, decl_attr_list
, attr_name
,
3684 tree attr
= lookup_attribute (IDENTIFIER_POINTER (attr_name
),
3687 if (attr
!= NULL_TREE
)
3689 /* Override existing arguments. Declarations are unique so we can
3690 modify this in place. */
3691 TREE_VALUE (attr
) = attr_args
;
3695 decl_attr_list
= tree_cons (attr_name
, attr_args
, decl_attr_list
);
3696 decl
= build_decl_attribute_variant (decl
, decl_attr_list
);
3703 #ifdef VALID_MACHINE_TYPE_ATTRIBUTE
3705 /* Don't apply the attribute to both the decl and the type. */;
3706 else if (VALID_MACHINE_TYPE_ATTRIBUTE (type
, type_attr_list
, attr_name
,
3709 tree attr
= lookup_attribute (IDENTIFIER_POINTER (attr_name
),
3712 if (attr
!= NULL_TREE
)
3714 /* Override existing arguments.
3715 ??? This currently works since attribute arguments are not
3716 included in `attribute_hash_list'. Something more complicated
3717 may be needed in the future. */
3718 TREE_VALUE (attr
) = attr_args
;
3722 /* If this is part of a declaration, create a type variant,
3723 otherwise, this is part of a type definition, so add it
3724 to the base type. */
3725 type_attr_list
= tree_cons (attr_name
, attr_args
, type_attr_list
);
3727 type
= build_type_attribute_variant (type
, type_attr_list
);
3729 TYPE_ATTRIBUTES (type
) = type_attr_list
;
3733 TREE_TYPE (decl
) = type
;
3738 /* Handle putting a type attribute on pointer-to-function-type by putting
3739 the attribute on the function type. */
3740 else if (POINTER_TYPE_P (type
)
3741 && TREE_CODE (TREE_TYPE (type
)) == FUNCTION_TYPE
3742 && VALID_MACHINE_TYPE_ATTRIBUTE (TREE_TYPE (type
), type_attr_list
,
3743 attr_name
, attr_args
))
3745 tree inner_type
= TREE_TYPE (type
);
3746 tree inner_attr_list
= TYPE_ATTRIBUTES (inner_type
);
3747 tree attr
= lookup_attribute (IDENTIFIER_POINTER (attr_name
),
3750 if (attr
!= NULL_TREE
)
3751 TREE_VALUE (attr
) = attr_args
;
3754 inner_attr_list
= tree_cons (attr_name
, attr_args
, inner_attr_list
);
3755 inner_type
= build_type_attribute_variant (inner_type
,
3760 TREE_TYPE (decl
) = build_pointer_type (inner_type
);
3763 /* Clear TYPE_POINTER_TO for the old inner type, since
3764 `type' won't be pointing to it anymore. */
3765 TYPE_POINTER_TO (TREE_TYPE (type
)) = NULL_TREE
;
3766 TREE_TYPE (type
) = inner_type
;
3776 /* Return non-zero if IDENT is a valid name for attribute ATTR,
3779 We try both `text' and `__text__', ATTR may be either one. */
3780 /* ??? It might be a reasonable simplification to require ATTR to be only
3781 `text'. One might then also require attribute lists to be stored in
3782 their canonicalized form. */
3785 is_attribute_p (attr
, ident
)
3789 int ident_len
, attr_len
;
3792 if (TREE_CODE (ident
) != IDENTIFIER_NODE
)
3795 if (strcmp (attr
, IDENTIFIER_POINTER (ident
)) == 0)
3798 p
= IDENTIFIER_POINTER (ident
);
3799 ident_len
= strlen (p
);
3800 attr_len
= strlen (attr
);
3802 /* If ATTR is `__text__', IDENT must be `text'; and vice versa. */
3806 || attr
[attr_len
- 2] != '_'
3807 || attr
[attr_len
- 1] != '_')
3809 if (ident_len
== attr_len
- 4
3810 && strncmp (attr
+ 2, p
, attr_len
- 4) == 0)
3815 if (ident_len
== attr_len
+ 4
3816 && p
[0] == '_' && p
[1] == '_'
3817 && p
[ident_len
- 2] == '_' && p
[ident_len
- 1] == '_'
3818 && strncmp (attr
, p
+ 2, attr_len
) == 0)
3825 /* Given an attribute name and a list of attributes, return a pointer to the
3826 attribute's list element if the attribute is part of the list, or NULL_TREE
3830 lookup_attribute (attr_name
, list
)
3831 const char *attr_name
;
3836 for (l
= list
; l
; l
= TREE_CHAIN (l
))
3838 if (TREE_CODE (TREE_PURPOSE (l
)) != IDENTIFIER_NODE
)
3840 if (is_attribute_p (attr_name
, TREE_PURPOSE (l
)))
3847 /* Return an attribute list that is the union of a1 and a2. */
3850 merge_attributes (a1
, a2
)
3851 register tree a1
, a2
;
3855 /* Either one unset? Take the set one. */
3857 if ((attributes
= a1
) == 0)
3860 /* One that completely contains the other? Take it. */
3862 else if (a2
!= 0 && ! attribute_list_contained (a1
, a2
))
3864 if (attribute_list_contained (a2
, a1
))
3868 /* Pick the longest list, and hang on the other list. */
3869 /* ??? For the moment we punt on the issue of attrs with args. */
3871 if (list_length (a1
) < list_length (a2
))
3872 attributes
= a2
, a2
= a1
;
3874 for (; a2
!= 0; a2
= TREE_CHAIN (a2
))
3875 if (lookup_attribute (IDENTIFIER_POINTER (TREE_PURPOSE (a2
)),
3876 attributes
) == NULL_TREE
)
3878 a1
= copy_node (a2
);
3879 TREE_CHAIN (a1
) = attributes
;
3887 /* Given types T1 and T2, merge their attributes and return
3891 merge_machine_type_attributes (t1
, t2
)
3894 #ifdef MERGE_MACHINE_TYPE_ATTRIBUTES
3895 return MERGE_MACHINE_TYPE_ATTRIBUTES (t1
, t2
);
3897 return merge_attributes (TYPE_ATTRIBUTES (t1
),
3898 TYPE_ATTRIBUTES (t2
));
3902 /* Given decls OLDDECL and NEWDECL, merge their attributes and return
3906 merge_machine_decl_attributes (olddecl
, newdecl
)
3907 tree olddecl
, newdecl
;
3909 #ifdef MERGE_MACHINE_DECL_ATTRIBUTES
3910 return MERGE_MACHINE_DECL_ATTRIBUTES (olddecl
, newdecl
);
3912 return merge_attributes (DECL_MACHINE_ATTRIBUTES (olddecl
),
3913 DECL_MACHINE_ATTRIBUTES (newdecl
));
3917 /* Set the type qualifiers for TYPE to TYPE_QUALS, which is a bitmask
3918 of the various TYPE_QUAL values. */
3921 set_type_quals (type
, type_quals
)
3925 TYPE_READONLY (type
) = (type_quals
& TYPE_QUAL_CONST
) != 0;
3926 TYPE_VOLATILE (type
) = (type_quals
& TYPE_QUAL_VOLATILE
) != 0;
3927 TYPE_RESTRICT (type
) = (type_quals
& TYPE_QUAL_RESTRICT
) != 0;
3930 /* Given a type node TYPE and a TYPE_QUALIFIER_SET, return a type for
3931 the same kind of data as TYPE describes. Variants point to the
3932 "main variant" (which has no qualifiers set) via TYPE_MAIN_VARIANT,
3933 and it points to a chain of other variants so that duplicate
3934 variants are never made. Only main variants should ever appear as
3935 types of expressions. */
3938 build_qualified_type (type
, type_quals
)
3944 /* Search the chain of variants to see if there is already one there just
3945 like the one we need to have. If so, use that existing one. We must
3946 preserve the TYPE_NAME, since there is code that depends on this. */
3948 for (t
= TYPE_MAIN_VARIANT (type
); t
; t
= TYPE_NEXT_VARIANT (t
))
3949 if (TYPE_QUALS (t
) == type_quals
&& TYPE_NAME (t
) == TYPE_NAME (type
))
3952 /* We need a new one. */
3953 t
= build_type_copy (type
);
3954 set_type_quals (t
, type_quals
);
3958 /* Create a new variant of TYPE, equivalent but distinct.
3959 This is so the caller can modify it. */
3962 build_type_copy (type
)
3965 register tree t
, m
= TYPE_MAIN_VARIANT (type
);
3966 register struct obstack
*ambient_obstack
= current_obstack
;
3968 current_obstack
= TYPE_OBSTACK (type
);
3969 t
= copy_node (type
);
3970 current_obstack
= ambient_obstack
;
3972 TYPE_POINTER_TO (t
) = 0;
3973 TYPE_REFERENCE_TO (t
) = 0;
3975 /* Add this type to the chain of variants of TYPE. */
3976 TYPE_NEXT_VARIANT (t
) = TYPE_NEXT_VARIANT (m
);
3977 TYPE_NEXT_VARIANT (m
) = t
;
3982 /* Hashing of types so that we don't make duplicates.
3983 The entry point is `type_hash_canon'. */
3985 /* Compute a hash code for a list of types (chain of TREE_LIST nodes
3986 with types in the TREE_VALUE slots), by adding the hash codes
3987 of the individual types. */
3990 type_hash_list (list
)
3993 unsigned int hashcode
;
3996 for (hashcode
= 0, tail
= list
; tail
; tail
= TREE_CHAIN (tail
))
3997 hashcode
+= TYPE_HASH (TREE_VALUE (tail
));
4002 /* These are the Hashtable callback functions. */
4004 /* Returns true if the types are equal. */
4007 type_hash_eq (va
, vb
)
4011 const struct type_hash
*a
= va
, *b
= vb
;
4012 if (a
->hash
== b
->hash
4013 && TREE_CODE (a
->type
) == TREE_CODE (b
->type
)
4014 && TREE_TYPE (a
->type
) == TREE_TYPE (b
->type
)
4015 && attribute_list_equal (TYPE_ATTRIBUTES (a
->type
),
4016 TYPE_ATTRIBUTES (b
->type
))
4017 && TYPE_ALIGN (a
->type
) == TYPE_ALIGN (b
->type
)
4018 && (TYPE_MAX_VALUE (a
->type
) == TYPE_MAX_VALUE (b
->type
)
4019 || tree_int_cst_equal (TYPE_MAX_VALUE (a
->type
),
4020 TYPE_MAX_VALUE (b
->type
)))
4021 && (TYPE_MIN_VALUE (a
->type
) == TYPE_MIN_VALUE (b
->type
)
4022 || tree_int_cst_equal (TYPE_MIN_VALUE (a
->type
),
4023 TYPE_MIN_VALUE (b
->type
)))
4024 /* Note that TYPE_DOMAIN is TYPE_ARG_TYPES for FUNCTION_TYPE. */
4025 && (TYPE_DOMAIN (a
->type
) == TYPE_DOMAIN (b
->type
)
4026 || (TYPE_DOMAIN (a
->type
)
4027 && TREE_CODE (TYPE_DOMAIN (a
->type
)) == TREE_LIST
4028 && TYPE_DOMAIN (b
->type
)
4029 && TREE_CODE (TYPE_DOMAIN (b
->type
)) == TREE_LIST
4030 && type_list_equal (TYPE_DOMAIN (a
->type
),
4031 TYPE_DOMAIN (b
->type
)))))
4036 /* Return the cached hash value. */
4039 type_hash_hash (item
)
4042 return ((const struct type_hash
*)item
)->hash
;
4045 /* Look in the type hash table for a type isomorphic to TYPE.
4046 If one is found, return it. Otherwise return 0. */
4049 type_hash_lookup (hashcode
, type
)
4050 unsigned int hashcode
;
4053 struct type_hash
*h
, in
;
4055 /* The TYPE_ALIGN field of a type is set by layout_type(), so we
4056 must call that routine before comparing TYPE_ALIGNs. */
4062 h
= htab_find_with_hash (type_hash_table
, &in
, hashcode
);
4068 /* Add an entry to the type-hash-table
4069 for a type TYPE whose hash code is HASHCODE. */
4072 type_hash_add (hashcode
, type
)
4073 unsigned int hashcode
;
4076 struct type_hash
*h
;
4079 h
= (struct type_hash
*) permalloc (sizeof (struct type_hash
));
4082 loc
= htab_find_slot_with_hash (type_hash_table
, h
, hashcode
, INSERT
);
4083 *(struct type_hash
**) loc
= h
;
4086 /* Given TYPE, and HASHCODE its hash code, return the canonical
4087 object for an identical type if one already exists.
4088 Otherwise, return TYPE, and record it as the canonical object
4089 if it is a permanent object.
4091 To use this function, first create a type of the sort you want.
4092 Then compute its hash code from the fields of the type that
4093 make it different from other similar types.
4094 Then call this function and use the value.
4095 This function frees the type you pass in if it is a duplicate. */
4097 /* Set to 1 to debug without canonicalization. Never set by program. */
4098 int debug_no_type_hash
= 0;
4101 type_hash_canon (hashcode
, type
)
4102 unsigned int hashcode
;
4107 if (debug_no_type_hash
)
4110 t1
= type_hash_lookup (hashcode
, type
);
4114 obstack_free (TYPE_OBSTACK (type
), type
);
4116 #ifdef GATHER_STATISTICS
4117 tree_node_counts
[(int) t_kind
]--;
4118 tree_node_sizes
[(int) t_kind
] -= sizeof (struct tree_type
);
4123 /* If this is a permanent type, record it for later reuse. */
4124 if (ggc_p
|| TREE_PERMANENT (type
))
4125 type_hash_add (hashcode
, type
);
4130 /* Callback function for htab_traverse. */
4133 mark_hash_entry (entry
, param
)
4135 void *param ATTRIBUTE_UNUSED
;
4137 struct type_hash
*p
= *(struct type_hash
**)entry
;
4139 ggc_mark_tree (p
->type
);
4141 /* Continue scan. */
4145 /* Mark ARG (which is really a htab_t *) for GC. */
4148 mark_type_hash (arg
)
4151 htab_t t
= *(htab_t
*) arg
;
4153 htab_traverse (t
, mark_hash_entry
, 0);
4157 print_type_hash_statistics ()
4159 fprintf (stderr
, "Type hash: size %ld, %ld elements, %f collisions\n",
4160 (long) htab_size (type_hash_table
),
4161 (long) htab_elements (type_hash_table
),
4162 htab_collisions (type_hash_table
));
4165 /* Compute a hash code for a list of attributes (chain of TREE_LIST nodes
4166 with names in the TREE_PURPOSE slots and args in the TREE_VALUE slots),
4167 by adding the hash codes of the individual attributes. */
4170 attribute_hash_list (list
)
4173 unsigned int hashcode
;
4176 for (hashcode
= 0, tail
= list
; tail
; tail
= TREE_CHAIN (tail
))
4177 /* ??? Do we want to add in TREE_VALUE too? */
4178 hashcode
+= TYPE_HASH (TREE_PURPOSE (tail
));
4182 /* Given two lists of attributes, return true if list l2 is
4183 equivalent to l1. */
4186 attribute_list_equal (l1
, l2
)
4189 return attribute_list_contained (l1
, l2
)
4190 && attribute_list_contained (l2
, l1
);
4193 /* Given two lists of attributes, return true if list L2 is
4194 completely contained within L1. */
4195 /* ??? This would be faster if attribute names were stored in a canonicalized
4196 form. Otherwise, if L1 uses `foo' and L2 uses `__foo__', the long method
4197 must be used to show these elements are equivalent (which they are). */
4198 /* ??? It's not clear that attributes with arguments will always be handled
4202 attribute_list_contained (l1
, l2
)
4205 register tree t1
, t2
;
4207 /* First check the obvious, maybe the lists are identical. */
4211 /* Maybe the lists are similar. */
4212 for (t1
= l1
, t2
= l2
;
4214 && TREE_PURPOSE (t1
) == TREE_PURPOSE (t2
)
4215 && TREE_VALUE (t1
) == TREE_VALUE (t2
);
4216 t1
= TREE_CHAIN (t1
), t2
= TREE_CHAIN (t2
));
4218 /* Maybe the lists are equal. */
4219 if (t1
== 0 && t2
== 0)
4222 for (; t2
!= 0; t2
= TREE_CHAIN (t2
))
4225 = lookup_attribute (IDENTIFIER_POINTER (TREE_PURPOSE (t2
)), l1
);
4230 if (simple_cst_equal (TREE_VALUE (t2
), TREE_VALUE (attr
)) != 1)
4237 /* Given two lists of types
4238 (chains of TREE_LIST nodes with types in the TREE_VALUE slots)
4239 return 1 if the lists contain the same types in the same order.
4240 Also, the TREE_PURPOSEs must match. */
4243 type_list_equal (l1
, l2
)
4246 register tree t1
, t2
;
4248 for (t1
= l1
, t2
= l2
; t1
&& t2
; t1
= TREE_CHAIN (t1
), t2
= TREE_CHAIN (t2
))
4249 if (TREE_VALUE (t1
) != TREE_VALUE (t2
)
4250 || (TREE_PURPOSE (t1
) != TREE_PURPOSE (t2
)
4251 && ! (1 == simple_cst_equal (TREE_PURPOSE (t1
), TREE_PURPOSE (t2
))
4252 && (TREE_TYPE (TREE_PURPOSE (t1
))
4253 == TREE_TYPE (TREE_PURPOSE (t2
))))))
4259 /* Nonzero if integer constants T1 and T2
4260 represent the same constant value. */
4263 tree_int_cst_equal (t1
, t2
)
4269 if (t1
== 0 || t2
== 0)
4272 if (TREE_CODE (t1
) == INTEGER_CST
4273 && TREE_CODE (t2
) == INTEGER_CST
4274 && TREE_INT_CST_LOW (t1
) == TREE_INT_CST_LOW (t2
)
4275 && TREE_INT_CST_HIGH (t1
) == TREE_INT_CST_HIGH (t2
))
4281 /* Nonzero if integer constants T1 and T2 represent values that satisfy <.
4282 The precise way of comparison depends on their data type. */
4285 tree_int_cst_lt (t1
, t2
)
4291 if (! TREE_UNSIGNED (TREE_TYPE (t1
)))
4292 return INT_CST_LT (t1
, t2
);
4294 return INT_CST_LT_UNSIGNED (t1
, t2
);
4297 /* Return 1 if T is an INTEGER_CST that can be represented in a single
4298 HOST_WIDE_INT value. If POS is nonzero, the result must be positive. */
4301 host_integerp (t
, pos
)
4305 return (TREE_CODE (t
) == INTEGER_CST
4306 && ! TREE_OVERFLOW (t
)
4307 && ((TREE_INT_CST_HIGH (t
) == 0
4308 && (HOST_WIDE_INT
) TREE_INT_CST_LOW (t
) >= 0)
4309 || (! pos
&& TREE_INT_CST_HIGH (t
) == -1
4310 && (HOST_WIDE_INT
) TREE_INT_CST_LOW (t
) < 0)));
4313 /* Return the HOST_WIDE_INT least significant bits of T if it is an
4314 INTEGER_CST and there is no overflow. POS is nonzero if the result must
4315 be positive. Abort if we cannot satisfy the above conditions. */
4318 tree_low_cst (t
, pos
)
4322 if (host_integerp (t
, pos
))
4323 return TREE_INT_CST_LOW (t
);
4328 /* Return the most significant bit of the integer constant T. */
4331 tree_int_cst_msb (t
)
4338 /* Note that using TYPE_PRECISION here is wrong. We care about the
4339 actual bits, not the (arbitrary) range of the type. */
4340 prec
= GET_MODE_BITSIZE (TYPE_MODE (TREE_TYPE (t
))) - 1;
4341 rshift_double (TREE_INT_CST_LOW (t
), TREE_INT_CST_HIGH (t
), prec
,
4342 2 * HOST_BITS_PER_WIDE_INT
, &l
, &h
, 0);
4343 return (l
& 1) == 1;
4346 /* Return an indication of the sign of the integer constant T.
4347 The return value is -1 if T < 0, 0 if T == 0, and 1 if T > 0.
4348 Note that -1 will never be returned it T's type is unsigned. */
4351 tree_int_cst_sgn (t
)
4354 if (TREE_INT_CST_LOW (t
) == 0 && TREE_INT_CST_HIGH (t
) == 0)
4356 else if (TREE_UNSIGNED (TREE_TYPE (t
)))
4358 else if (TREE_INT_CST_HIGH (t
) < 0)
4364 /* Return true if `t' is known to be non-negative. */
4367 tree_expr_nonnegative_p (t
)
4370 switch (TREE_CODE (t
))
4373 return tree_int_cst_sgn (t
) >= 0;
4375 return tree_expr_nonnegative_p (TREE_OPERAND (t
, 1))
4376 && tree_expr_nonnegative_p (TREE_OPERAND (t
, 2));
4378 /* We don't know sign of `t', so be safe and return false. */
4383 /* Compare two constructor-element-type constants. Return 1 if the lists
4384 are known to be equal; otherwise return 0. */
4387 simple_cst_list_equal (l1
, l2
)
4390 while (l1
!= NULL_TREE
&& l2
!= NULL_TREE
)
4392 if (simple_cst_equal (TREE_VALUE (l1
), TREE_VALUE (l2
)) != 1)
4395 l1
= TREE_CHAIN (l1
);
4396 l2
= TREE_CHAIN (l2
);
4402 /* Return truthvalue of whether T1 is the same tree structure as T2.
4403 Return 1 if they are the same.
4404 Return 0 if they are understandably different.
4405 Return -1 if either contains tree structure not understood by
4409 simple_cst_equal (t1
, t2
)
4412 register enum tree_code code1
, code2
;
4418 if (t1
== 0 || t2
== 0)
4421 code1
= TREE_CODE (t1
);
4422 code2
= TREE_CODE (t2
);
4424 if (code1
== NOP_EXPR
|| code1
== CONVERT_EXPR
|| code1
== NON_LVALUE_EXPR
)
4426 if (code2
== NOP_EXPR
|| code2
== CONVERT_EXPR
4427 || code2
== NON_LVALUE_EXPR
)
4428 return simple_cst_equal (TREE_OPERAND (t1
, 0), TREE_OPERAND (t2
, 0));
4430 return simple_cst_equal (TREE_OPERAND (t1
, 0), t2
);
4433 else if (code2
== NOP_EXPR
|| code2
== CONVERT_EXPR
4434 || code2
== NON_LVALUE_EXPR
)
4435 return simple_cst_equal (t1
, TREE_OPERAND (t2
, 0));
4443 return (TREE_INT_CST_LOW (t1
) == TREE_INT_CST_LOW (t2
)
4444 && TREE_INT_CST_HIGH (t1
) == TREE_INT_CST_HIGH (t2
));
4447 return REAL_VALUES_IDENTICAL (TREE_REAL_CST (t1
), TREE_REAL_CST (t2
));
4450 return (TREE_STRING_LENGTH (t1
) == TREE_STRING_LENGTH (t2
)
4451 && ! bcmp (TREE_STRING_POINTER (t1
), TREE_STRING_POINTER (t2
),
4452 TREE_STRING_LENGTH (t1
)));
4455 if (CONSTRUCTOR_ELTS (t1
) == CONSTRUCTOR_ELTS (t2
))
4461 return simple_cst_equal (TREE_OPERAND (t1
, 0), TREE_OPERAND (t2
, 0));
4464 cmp
= simple_cst_equal (TREE_OPERAND (t1
, 0), TREE_OPERAND (t2
, 0));
4468 simple_cst_list_equal (TREE_OPERAND (t1
, 1), TREE_OPERAND (t2
, 1));
4471 /* Special case: if either target is an unallocated VAR_DECL,
4472 it means that it's going to be unified with whatever the
4473 TARGET_EXPR is really supposed to initialize, so treat it
4474 as being equivalent to anything. */
4475 if ((TREE_CODE (TREE_OPERAND (t1
, 0)) == VAR_DECL
4476 && DECL_NAME (TREE_OPERAND (t1
, 0)) == NULL_TREE
4477 && DECL_RTL (TREE_OPERAND (t1
, 0)) == 0)
4478 || (TREE_CODE (TREE_OPERAND (t2
, 0)) == VAR_DECL
4479 && DECL_NAME (TREE_OPERAND (t2
, 0)) == NULL_TREE
4480 && DECL_RTL (TREE_OPERAND (t2
, 0)) == 0))
4483 cmp
= simple_cst_equal (TREE_OPERAND (t1
, 0), TREE_OPERAND (t2
, 0));
4488 return simple_cst_equal (TREE_OPERAND (t1
, 1), TREE_OPERAND (t2
, 1));
4490 case WITH_CLEANUP_EXPR
:
4491 cmp
= simple_cst_equal (TREE_OPERAND (t1
, 0), TREE_OPERAND (t2
, 0));
4495 return simple_cst_equal (TREE_OPERAND (t1
, 2), TREE_OPERAND (t1
, 2));
4498 if (TREE_OPERAND (t1
, 1) == TREE_OPERAND (t2
, 1))
4499 return simple_cst_equal (TREE_OPERAND (t1
, 0), TREE_OPERAND (t2
, 0));
4513 /* This general rule works for most tree codes. All exceptions should be
4514 handled above. If this is a language-specific tree code, we can't
4515 trust what might be in the operand, so say we don't know
4517 if ((int) code1
>= (int) LAST_AND_UNUSED_TREE_CODE
)
4520 switch (TREE_CODE_CLASS (code1
))
4529 for (i
= 0; i
< tree_code_length
[(int) code1
]; i
++)
4531 cmp
= simple_cst_equal (TREE_OPERAND (t1
, i
), TREE_OPERAND (t2
, i
));
4543 /* Compare the value of T, an INTEGER_CST, with U, an unsigned integer value.
4544 Return -1, 0, or 1 if the value of T is less than, equal to, or greater
4545 than U, respectively. */
4548 compare_tree_int (t
, u
)
4552 if (tree_int_cst_sgn (t
) < 0)
4554 else if (TREE_INT_CST_HIGH (t
) != 0)
4556 else if (TREE_INT_CST_LOW (t
) == u
)
4558 else if (TREE_INT_CST_LOW (t
) < u
)
4564 /* Constructors for pointer, array and function types.
4565 (RECORD_TYPE, UNION_TYPE and ENUMERAL_TYPE nodes are
4566 constructed by language-dependent code, not here.) */
4568 /* Construct, lay out and return the type of pointers to TO_TYPE.
4569 If such a type has already been constructed, reuse it. */
4572 build_pointer_type (to_type
)
4575 register tree t
= TYPE_POINTER_TO (to_type
);
4577 /* First, if we already have a type for pointers to TO_TYPE, use it. */
4582 /* We need a new one. Put this in the same obstack as TO_TYPE. */
4583 push_obstacks (TYPE_OBSTACK (to_type
), TYPE_OBSTACK (to_type
));
4584 t
= make_node (POINTER_TYPE
);
4587 TREE_TYPE (t
) = to_type
;
4589 /* Record this type as the pointer to TO_TYPE. */
4590 TYPE_POINTER_TO (to_type
) = t
;
4592 /* Lay out the type. This function has many callers that are concerned
4593 with expression-construction, and this simplifies them all.
4594 Also, it guarantees the TYPE_SIZE is in the same obstack as the type. */
4600 /* Build the node for the type of references-to-TO_TYPE. */
4603 build_reference_type (to_type
)
4606 register tree t
= TYPE_REFERENCE_TO (to_type
);
4608 /* First, if we already have a type for pointers to TO_TYPE, use it. */
4613 /* We need a new one. Put this in the same obstack as TO_TYPE. */
4614 push_obstacks (TYPE_OBSTACK (to_type
), TYPE_OBSTACK (to_type
));
4615 t
= make_node (REFERENCE_TYPE
);
4618 TREE_TYPE (t
) = to_type
;
4620 /* Record this type as the pointer to TO_TYPE. */
4621 TYPE_REFERENCE_TO (to_type
) = t
;
4628 /* Create a type of integers to be the TYPE_DOMAIN of an ARRAY_TYPE.
4629 MAXVAL should be the maximum value in the domain
4630 (one less than the length of the array).
4632 The maximum value that MAXVAL can have is INT_MAX for a HOST_WIDE_INT.
4633 We don't enforce this limit, that is up to caller (e.g. language front end).
4634 The limit exists because the result is a signed type and we don't handle
4635 sizes that use more than one HOST_WIDE_INT. */
4638 build_index_type (maxval
)
4641 register tree itype
= make_node (INTEGER_TYPE
);
4643 TREE_TYPE (itype
) = sizetype
;
4644 TYPE_PRECISION (itype
) = TYPE_PRECISION (sizetype
);
4645 TYPE_MIN_VALUE (itype
) = size_zero_node
;
4647 push_obstacks (TYPE_OBSTACK (itype
), TYPE_OBSTACK (itype
));
4648 TYPE_MAX_VALUE (itype
) = convert (sizetype
, maxval
);
4651 TYPE_MODE (itype
) = TYPE_MODE (sizetype
);
4652 TYPE_SIZE (itype
) = TYPE_SIZE (sizetype
);
4653 TYPE_SIZE_UNIT (itype
) = TYPE_SIZE_UNIT (sizetype
);
4654 TYPE_ALIGN (itype
) = TYPE_ALIGN (sizetype
);
4656 if (host_integerp (maxval
, 1))
4657 return type_hash_canon (tree_low_cst (maxval
, 1), itype
);
4662 /* Create a range of some discrete type TYPE (an INTEGER_TYPE,
4663 ENUMERAL_TYPE, BOOLEAN_TYPE, or CHAR_TYPE), with
4664 low bound LOWVAL and high bound HIGHVAL.
4665 if TYPE==NULL_TREE, sizetype is used. */
4668 build_range_type (type
, lowval
, highval
)
4669 tree type
, lowval
, highval
;
4671 register tree itype
= make_node (INTEGER_TYPE
);
4673 TREE_TYPE (itype
) = type
;
4674 if (type
== NULL_TREE
)
4677 push_obstacks (TYPE_OBSTACK (itype
), TYPE_OBSTACK (itype
));
4678 TYPE_MIN_VALUE (itype
) = convert (type
, lowval
);
4679 TYPE_MAX_VALUE (itype
) = highval
? convert (type
, highval
) : NULL
;
4682 TYPE_PRECISION (itype
) = TYPE_PRECISION (type
);
4683 TYPE_MODE (itype
) = TYPE_MODE (type
);
4684 TYPE_SIZE (itype
) = TYPE_SIZE (type
);
4685 TYPE_SIZE_UNIT (itype
) = TYPE_SIZE_UNIT (type
);
4686 TYPE_ALIGN (itype
) = TYPE_ALIGN (type
);
4688 if (host_integerp (lowval
, 0) && highval
!= 0 && host_integerp (highval
, 0))
4689 return type_hash_canon (tree_low_cst (highval
, 0)
4690 - tree_low_cst (lowval
, 0),
4696 /* Just like build_index_type, but takes lowval and highval instead
4697 of just highval (maxval). */
4700 build_index_2_type (lowval
,highval
)
4701 tree lowval
, highval
;
4703 return build_range_type (sizetype
, lowval
, highval
);
4706 /* Return nonzero iff ITYPE1 and ITYPE2 are equal (in the LISP sense).
4707 Needed because when index types are not hashed, equal index types
4708 built at different times appear distinct, even though structurally,
4712 index_type_equal (itype1
, itype2
)
4713 tree itype1
, itype2
;
4715 if (TREE_CODE (itype1
) != TREE_CODE (itype2
))
4718 if (TREE_CODE (itype1
) == INTEGER_TYPE
)
4720 if (TYPE_PRECISION (itype1
) != TYPE_PRECISION (itype2
)
4721 || TYPE_MODE (itype1
) != TYPE_MODE (itype2
)
4722 || simple_cst_equal (TYPE_SIZE (itype1
), TYPE_SIZE (itype2
)) != 1
4723 || TYPE_ALIGN (itype1
) != TYPE_ALIGN (itype2
))
4726 if (1 == simple_cst_equal (TYPE_MIN_VALUE (itype1
),
4727 TYPE_MIN_VALUE (itype2
))
4728 && 1 == simple_cst_equal (TYPE_MAX_VALUE (itype1
),
4729 TYPE_MAX_VALUE (itype2
)))
4736 /* Construct, lay out and return the type of arrays of elements with ELT_TYPE
4737 and number of elements specified by the range of values of INDEX_TYPE.
4738 If such a type has already been constructed, reuse it. */
4741 build_array_type (elt_type
, index_type
)
4742 tree elt_type
, index_type
;
4745 unsigned int hashcode
;
4747 if (TREE_CODE (elt_type
) == FUNCTION_TYPE
)
4749 error ("arrays of functions are not meaningful");
4750 elt_type
= integer_type_node
;
4753 /* Make sure TYPE_POINTER_TO (elt_type) is filled in. */
4754 build_pointer_type (elt_type
);
4756 /* Allocate the array after the pointer type,
4757 in case we free it in type_hash_canon. */
4758 t
= make_node (ARRAY_TYPE
);
4759 TREE_TYPE (t
) = elt_type
;
4760 TYPE_DOMAIN (t
) = index_type
;
4762 if (index_type
== 0)
4767 hashcode
= TYPE_HASH (elt_type
) + TYPE_HASH (index_type
);
4768 t
= type_hash_canon (hashcode
, t
);
4770 if (!COMPLETE_TYPE_P (t
))
4775 /* Return the TYPE of the elements comprising
4776 the innermost dimension of ARRAY. */
4779 get_inner_array_type (array
)
4782 tree type
= TREE_TYPE (array
);
4784 while (TREE_CODE (type
) == ARRAY_TYPE
)
4785 type
= TREE_TYPE (type
);
4790 /* Construct, lay out and return
4791 the type of functions returning type VALUE_TYPE
4792 given arguments of types ARG_TYPES.
4793 ARG_TYPES is a chain of TREE_LIST nodes whose TREE_VALUEs
4794 are data type nodes for the arguments of the function.
4795 If such a type has already been constructed, reuse it. */
4798 build_function_type (value_type
, arg_types
)
4799 tree value_type
, arg_types
;
4802 unsigned int hashcode
;
4804 if (TREE_CODE (value_type
) == FUNCTION_TYPE
)
4806 error ("function return type cannot be function");
4807 value_type
= integer_type_node
;
4810 /* Make a node of the sort we want. */
4811 t
= make_node (FUNCTION_TYPE
);
4812 TREE_TYPE (t
) = value_type
;
4813 TYPE_ARG_TYPES (t
) = arg_types
;
4815 /* If we already have such a type, use the old one and free this one. */
4816 hashcode
= TYPE_HASH (value_type
) + type_hash_list (arg_types
);
4817 t
= type_hash_canon (hashcode
, t
);
4819 if (!COMPLETE_TYPE_P (t
))
4824 /* Construct, lay out and return the type of methods belonging to class
4825 BASETYPE and whose arguments and values are described by TYPE.
4826 If that type exists already, reuse it.
4827 TYPE must be a FUNCTION_TYPE node. */
4830 build_method_type (basetype
, type
)
4831 tree basetype
, type
;
4834 unsigned int hashcode
;
4836 /* Make a node of the sort we want. */
4837 t
= make_node (METHOD_TYPE
);
4839 if (TREE_CODE (type
) != FUNCTION_TYPE
)
4842 TYPE_METHOD_BASETYPE (t
) = TYPE_MAIN_VARIANT (basetype
);
4843 TREE_TYPE (t
) = TREE_TYPE (type
);
4845 /* The actual arglist for this function includes a "hidden" argument
4846 which is "this". Put it into the list of argument types. */
4849 = tree_cons (NULL_TREE
,
4850 build_pointer_type (basetype
), TYPE_ARG_TYPES (type
));
4852 /* If we already have such a type, use the old one and free this one. */
4853 hashcode
= TYPE_HASH (basetype
) + TYPE_HASH (type
);
4854 t
= type_hash_canon (hashcode
, t
);
4856 if (!COMPLETE_TYPE_P (t
))
4862 /* Construct, lay out and return the type of offsets to a value
4863 of type TYPE, within an object of type BASETYPE.
4864 If a suitable offset type exists already, reuse it. */
4867 build_offset_type (basetype
, type
)
4868 tree basetype
, type
;
4871 unsigned int hashcode
;
4873 /* Make a node of the sort we want. */
4874 t
= make_node (OFFSET_TYPE
);
4876 TYPE_OFFSET_BASETYPE (t
) = TYPE_MAIN_VARIANT (basetype
);
4877 TREE_TYPE (t
) = type
;
4879 /* If we already have such a type, use the old one and free this one. */
4880 hashcode
= TYPE_HASH (basetype
) + TYPE_HASH (type
);
4881 t
= type_hash_canon (hashcode
, t
);
4883 if (!COMPLETE_TYPE_P (t
))
4889 /* Create a complex type whose components are COMPONENT_TYPE. */
4892 build_complex_type (component_type
)
4893 tree component_type
;
4896 unsigned int hashcode
;
4898 /* Make a node of the sort we want. */
4899 t
= make_node (COMPLEX_TYPE
);
4901 TREE_TYPE (t
) = TYPE_MAIN_VARIANT (component_type
);
4902 set_type_quals (t
, TYPE_QUALS (component_type
));
4904 /* If we already have such a type, use the old one and free this one. */
4905 hashcode
= TYPE_HASH (component_type
);
4906 t
= type_hash_canon (hashcode
, t
);
4908 if (!COMPLETE_TYPE_P (t
))
4911 /* If we are writing Dwarf2 output we need to create a name,
4912 since complex is a fundamental type. */
4913 if (write_symbols
== DWARF2_DEBUG
&& ! TYPE_NAME (t
))
4916 if (component_type
== char_type_node
)
4917 name
= "complex char";
4918 else if (component_type
== signed_char_type_node
)
4919 name
= "complex signed char";
4920 else if (component_type
== unsigned_char_type_node
)
4921 name
= "complex unsigned char";
4922 else if (component_type
== short_integer_type_node
)
4923 name
= "complex short int";
4924 else if (component_type
== short_unsigned_type_node
)
4925 name
= "complex short unsigned int";
4926 else if (component_type
== integer_type_node
)
4927 name
= "complex int";
4928 else if (component_type
== unsigned_type_node
)
4929 name
= "complex unsigned int";
4930 else if (component_type
== long_integer_type_node
)
4931 name
= "complex long int";
4932 else if (component_type
== long_unsigned_type_node
)
4933 name
= "complex long unsigned int";
4934 else if (component_type
== long_long_integer_type_node
)
4935 name
= "complex long long int";
4936 else if (component_type
== long_long_unsigned_type_node
)
4937 name
= "complex long long unsigned int";
4942 TYPE_NAME (t
) = get_identifier (name
);
4948 /* Return OP, stripped of any conversions to wider types as much as is safe.
4949 Converting the value back to OP's type makes a value equivalent to OP.
4951 If FOR_TYPE is nonzero, we return a value which, if converted to
4952 type FOR_TYPE, would be equivalent to converting OP to type FOR_TYPE.
4954 If FOR_TYPE is nonzero, unaligned bit-field references may be changed to the
4955 narrowest type that can hold the value, even if they don't exactly fit.
4956 Otherwise, bit-field references are changed to a narrower type
4957 only if they can be fetched directly from memory in that type.
4959 OP must have integer, real or enumeral type. Pointers are not allowed!
4961 There are some cases where the obvious value we could return
4962 would regenerate to OP if converted to OP's type,
4963 but would not extend like OP to wider types.
4964 If FOR_TYPE indicates such extension is contemplated, we eschew such values.
4965 For example, if OP is (unsigned short)(signed char)-1,
4966 we avoid returning (signed char)-1 if FOR_TYPE is int,
4967 even though extending that to an unsigned short would regenerate OP,
4968 since the result of extending (signed char)-1 to (int)
4969 is different from (int) OP. */
4972 get_unwidened (op
, for_type
)
4976 /* Set UNS initially if converting OP to FOR_TYPE is a zero-extension. */
4977 register tree type
= TREE_TYPE (op
);
4978 register unsigned final_prec
4979 = TYPE_PRECISION (for_type
!= 0 ? for_type
: type
);
4981 = (for_type
!= 0 && for_type
!= type
4982 && final_prec
> TYPE_PRECISION (type
)
4983 && TREE_UNSIGNED (type
));
4984 register tree win
= op
;
4986 while (TREE_CODE (op
) == NOP_EXPR
)
4988 register int bitschange
4989 = TYPE_PRECISION (TREE_TYPE (op
))
4990 - TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (op
, 0)));
4992 /* Truncations are many-one so cannot be removed.
4993 Unless we are later going to truncate down even farther. */
4995 && final_prec
> TYPE_PRECISION (TREE_TYPE (op
)))
4998 /* See what's inside this conversion. If we decide to strip it,
5000 op
= TREE_OPERAND (op
, 0);
5002 /* If we have not stripped any zero-extensions (uns is 0),
5003 we can strip any kind of extension.
5004 If we have previously stripped a zero-extension,
5005 only zero-extensions can safely be stripped.
5006 Any extension can be stripped if the bits it would produce
5007 are all going to be discarded later by truncating to FOR_TYPE. */
5011 if (! uns
|| final_prec
<= TYPE_PRECISION (TREE_TYPE (op
)))
5013 /* TREE_UNSIGNED says whether this is a zero-extension.
5014 Let's avoid computing it if it does not affect WIN
5015 and if UNS will not be needed again. */
5016 if ((uns
|| TREE_CODE (op
) == NOP_EXPR
)
5017 && TREE_UNSIGNED (TREE_TYPE (op
)))
5025 if (TREE_CODE (op
) == COMPONENT_REF
5026 /* Since type_for_size always gives an integer type. */
5027 && TREE_CODE (type
) != REAL_TYPE
5028 /* Don't crash if field not laid out yet. */
5029 && DECL_SIZE (TREE_OPERAND (op
, 1)) != 0)
5031 unsigned int innerprec
5032 = TREE_INT_CST_LOW (DECL_SIZE (TREE_OPERAND (op
, 1)));
5034 type
= type_for_size (innerprec
, TREE_UNSIGNED (TREE_OPERAND (op
, 1)));
5036 /* We can get this structure field in the narrowest type it fits in.
5037 If FOR_TYPE is 0, do this only for a field that matches the
5038 narrower type exactly and is aligned for it
5039 The resulting extension to its nominal type (a fullword type)
5040 must fit the same conditions as for other extensions. */
5042 if (innerprec
< TYPE_PRECISION (TREE_TYPE (op
))
5043 && (for_type
|| ! DECL_BIT_FIELD (TREE_OPERAND (op
, 1)))
5044 && (! uns
|| final_prec
<= innerprec
5045 || TREE_UNSIGNED (TREE_OPERAND (op
, 1)))
5048 win
= build (COMPONENT_REF
, type
, TREE_OPERAND (op
, 0),
5049 TREE_OPERAND (op
, 1));
5050 TREE_SIDE_EFFECTS (win
) = TREE_SIDE_EFFECTS (op
);
5051 TREE_THIS_VOLATILE (win
) = TREE_THIS_VOLATILE (op
);
5057 /* Return OP or a simpler expression for a narrower value
5058 which can be sign-extended or zero-extended to give back OP.
5059 Store in *UNSIGNEDP_PTR either 1 if the value should be zero-extended
5060 or 0 if the value should be sign-extended. */
5063 get_narrower (op
, unsignedp_ptr
)
5067 register int uns
= 0;
5069 register tree win
= op
;
5071 while (TREE_CODE (op
) == NOP_EXPR
)
5073 register int bitschange
5074 = (TYPE_PRECISION (TREE_TYPE (op
))
5075 - TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (op
, 0))));
5077 /* Truncations are many-one so cannot be removed. */
5081 /* See what's inside this conversion. If we decide to strip it,
5083 op
= TREE_OPERAND (op
, 0);
5087 /* An extension: the outermost one can be stripped,
5088 but remember whether it is zero or sign extension. */
5090 uns
= TREE_UNSIGNED (TREE_TYPE (op
));
5091 /* Otherwise, if a sign extension has been stripped,
5092 only sign extensions can now be stripped;
5093 if a zero extension has been stripped, only zero-extensions. */
5094 else if (uns
!= TREE_UNSIGNED (TREE_TYPE (op
)))
5098 else /* bitschange == 0 */
5100 /* A change in nominal type can always be stripped, but we must
5101 preserve the unsignedness. */
5103 uns
= TREE_UNSIGNED (TREE_TYPE (op
));
5110 if (TREE_CODE (op
) == COMPONENT_REF
5111 /* Since type_for_size always gives an integer type. */
5112 && TREE_CODE (TREE_TYPE (op
)) != REAL_TYPE
)
5114 unsigned int innerprec
5115 = TREE_INT_CST_LOW (DECL_SIZE (TREE_OPERAND (op
, 1)));
5117 tree type
= type_for_size (innerprec
, TREE_UNSIGNED (op
));
5119 /* We can get this structure field in a narrower type that fits it,
5120 but the resulting extension to its nominal type (a fullword type)
5121 must satisfy the same conditions as for other extensions.
5123 Do this only for fields that are aligned (not bit-fields),
5124 because when bit-field insns will be used there is no
5125 advantage in doing this. */
5127 if (innerprec
< TYPE_PRECISION (TREE_TYPE (op
))
5128 && ! DECL_BIT_FIELD (TREE_OPERAND (op
, 1))
5129 && (first
|| uns
== TREE_UNSIGNED (TREE_OPERAND (op
, 1)))
5133 uns
= TREE_UNSIGNED (TREE_OPERAND (op
, 1));
5134 win
= build (COMPONENT_REF
, type
, TREE_OPERAND (op
, 0),
5135 TREE_OPERAND (op
, 1));
5136 TREE_SIDE_EFFECTS (win
) = TREE_SIDE_EFFECTS (op
);
5137 TREE_THIS_VOLATILE (win
) = TREE_THIS_VOLATILE (op
);
5140 *unsignedp_ptr
= uns
;
5144 /* Nonzero if integer constant C has a value that is permissible
5145 for type TYPE (an INTEGER_TYPE). */
5148 int_fits_type_p (c
, type
)
5151 if (TREE_UNSIGNED (type
))
5152 return (! (TREE_CODE (TYPE_MAX_VALUE (type
)) == INTEGER_CST
5153 && INT_CST_LT_UNSIGNED (TYPE_MAX_VALUE (type
), c
))
5154 && ! (TREE_CODE (TYPE_MIN_VALUE (type
)) == INTEGER_CST
5155 && INT_CST_LT_UNSIGNED (c
, TYPE_MIN_VALUE (type
)))
5156 /* Negative ints never fit unsigned types. */
5157 && ! (TREE_INT_CST_HIGH (c
) < 0
5158 && ! TREE_UNSIGNED (TREE_TYPE (c
))));
5160 return (! (TREE_CODE (TYPE_MAX_VALUE (type
)) == INTEGER_CST
5161 && INT_CST_LT (TYPE_MAX_VALUE (type
), c
))
5162 && ! (TREE_CODE (TYPE_MIN_VALUE (type
)) == INTEGER_CST
5163 && INT_CST_LT (c
, TYPE_MIN_VALUE (type
)))
5164 /* Unsigned ints with top bit set never fit signed types. */
5165 && ! (TREE_INT_CST_HIGH (c
) < 0
5166 && TREE_UNSIGNED (TREE_TYPE (c
))));
5169 /* Given a DECL or TYPE, return the scope in which it was declared, or
5170 NULL_TREE if there is no containing scope. */
5173 get_containing_scope (t
)
5176 return (TYPE_P (t
) ? TYPE_CONTEXT (t
) : DECL_CONTEXT (t
));
5179 /* Return the innermost context enclosing DECL that is
5180 a FUNCTION_DECL, or zero if none. */
5183 decl_function_context (decl
)
5188 if (TREE_CODE (decl
) == ERROR_MARK
)
5191 if (TREE_CODE (decl
) == SAVE_EXPR
)
5192 context
= SAVE_EXPR_CONTEXT (decl
);
5194 /* C++ virtual functions use DECL_CONTEXT for the class of the vtable
5195 where we look up the function at runtime. Such functions always take
5196 a first argument of type 'pointer to real context'.
5198 C++ should really be fixed to use DECL_CONTEXT for the real context,
5199 and use something else for the "virtual context". */
5200 else if (TREE_CODE (decl
) == FUNCTION_DECL
&& DECL_VINDEX (decl
))
5203 (TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (TREE_TYPE (decl
)))));
5205 context
= DECL_CONTEXT (decl
);
5207 while (context
&& TREE_CODE (context
) != FUNCTION_DECL
)
5209 if (TREE_CODE (context
) == BLOCK
)
5210 context
= BLOCK_SUPERCONTEXT (context
);
5212 context
= get_containing_scope (context
);
5218 /* Return the innermost context enclosing DECL that is
5219 a RECORD_TYPE, UNION_TYPE or QUAL_UNION_TYPE, or zero if none.
5220 TYPE_DECLs and FUNCTION_DECLs are transparent to this function. */
5223 decl_type_context (decl
)
5226 tree context
= DECL_CONTEXT (decl
);
5230 if (TREE_CODE (context
) == RECORD_TYPE
5231 || TREE_CODE (context
) == UNION_TYPE
5232 || TREE_CODE (context
) == QUAL_UNION_TYPE
)
5235 if (TREE_CODE (context
) == TYPE_DECL
5236 || TREE_CODE (context
) == FUNCTION_DECL
)
5237 context
= DECL_CONTEXT (context
);
5239 else if (TREE_CODE (context
) == BLOCK
)
5240 context
= BLOCK_SUPERCONTEXT (context
);
5243 /* Unhandled CONTEXT!? */
5249 /* CALL is a CALL_EXPR. Return the declaration for the function
5250 called, or NULL_TREE if the called function cannot be
5254 get_callee_fndecl (call
)
5259 /* It's invalid to call this function with anything but a
5261 if (TREE_CODE (call
) != CALL_EXPR
)
5264 /* The first operand to the CALL is the address of the function
5266 addr
= TREE_OPERAND (call
, 0);
5268 /* If the address is just `&f' for some function `f', then we know
5269 that `f' is being called. */
5270 if (TREE_CODE (addr
) == ADDR_EXPR
5271 && TREE_CODE (TREE_OPERAND (addr
, 0)) == FUNCTION_DECL
)
5272 return TREE_OPERAND (addr
, 0);
5274 /* We couldn't figure out what was being called. */
5278 /* Print debugging information about the obstack O, named STR. */
5281 print_obstack_statistics (str
, o
)
5285 struct _obstack_chunk
*chunk
= o
->chunk
;
5289 n_alloc
+= o
->next_free
- chunk
->contents
;
5290 chunk
= chunk
->prev
;
5294 n_alloc
+= chunk
->limit
- &chunk
->contents
[0];
5295 chunk
= chunk
->prev
;
5297 fprintf (stderr
, "obstack %s: %u bytes, %d chunks\n",
5298 str
, n_alloc
, n_chunks
);
5301 /* Print debugging information about tree nodes generated during the compile,
5302 and any language-specific information. */
5305 dump_tree_statistics ()
5307 #ifdef GATHER_STATISTICS
5309 int total_nodes
, total_bytes
;
5312 fprintf (stderr
, "\n??? tree nodes created\n\n");
5313 #ifdef GATHER_STATISTICS
5314 fprintf (stderr
, "Kind Nodes Bytes\n");
5315 fprintf (stderr
, "-------------------------------------\n");
5316 total_nodes
= total_bytes
= 0;
5317 for (i
= 0; i
< (int) all_kinds
; i
++)
5319 fprintf (stderr
, "%-20s %6d %9d\n", tree_node_kind_names
[i
],
5320 tree_node_counts
[i
], tree_node_sizes
[i
]);
5321 total_nodes
+= tree_node_counts
[i
];
5322 total_bytes
+= tree_node_sizes
[i
];
5324 fprintf (stderr
, "%-20s %9d\n", "identifier names", id_string_size
);
5325 fprintf (stderr
, "-------------------------------------\n");
5326 fprintf (stderr
, "%-20s %6d %9d\n", "Total", total_nodes
, total_bytes
);
5327 fprintf (stderr
, "-------------------------------------\n");
5329 fprintf (stderr
, "(No per-node statistics)\n");
5331 print_obstack_statistics ("permanent_obstack", &permanent_obstack
);
5332 print_obstack_statistics ("maybepermanent_obstack", &maybepermanent_obstack
);
5333 print_obstack_statistics ("temporary_obstack", &temporary_obstack
);
5334 print_obstack_statistics ("momentary_obstack", &momentary_obstack
);
5335 print_obstack_statistics ("temp_decl_obstack", &temp_decl_obstack
);
5336 print_type_hash_statistics ();
5337 print_lang_statistics ();
5340 #define FILE_FUNCTION_PREFIX_LEN 9
5342 #ifndef NO_DOLLAR_IN_LABEL
5343 #define FILE_FUNCTION_FORMAT "_GLOBAL_$%s$%s"
5344 #else /* NO_DOLLAR_IN_LABEL */
5345 #ifndef NO_DOT_IN_LABEL
5346 #define FILE_FUNCTION_FORMAT "_GLOBAL_.%s.%s"
5347 #else /* NO_DOT_IN_LABEL */
5348 #define FILE_FUNCTION_FORMAT "_GLOBAL__%s_%s"
5349 #endif /* NO_DOT_IN_LABEL */
5350 #endif /* NO_DOLLAR_IN_LABEL */
5352 extern char *first_global_object_name
;
5353 extern char *weak_global_object_name
;
5355 /* Appends 6 random characters to TEMPLATE to (hopefully) avoid name
5356 clashes in cases where we can't reliably choose a unique name.
5358 Derived from mkstemp.c in libiberty. */
5361 append_random_chars (template)
5364 static const char letters
[]
5365 = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789";
5366 static unsigned HOST_WIDE_INT value
;
5367 unsigned HOST_WIDE_INT v
;
5369 #ifdef HAVE_GETTIMEOFDAY
5373 template += strlen (template);
5375 #ifdef HAVE_GETTIMEOFDAY
5376 /* Get some more or less random data. */
5377 gettimeofday (&tv
, NULL
);
5378 value
+= ((unsigned HOST_WIDE_INT
) tv
.tv_usec
<< 16) ^ tv
.tv_sec
^ getpid ();
5385 /* Fill in the random bits. */
5386 template[0] = letters
[v
% 62];
5388 template[1] = letters
[v
% 62];
5390 template[2] = letters
[v
% 62];
5392 template[3] = letters
[v
% 62];
5394 template[4] = letters
[v
% 62];
5396 template[5] = letters
[v
% 62];
5401 /* Generate a name for a function unique to this translation unit.
5402 TYPE is some string to identify the purpose of this function to the
5403 linker or collect2. */
5406 get_file_function_name_long (type
)
5412 if (first_global_object_name
)
5413 p
= first_global_object_name
;
5416 /* We don't have anything that we know to be unique to this translation
5417 unit, so use what we do have and throw in some randomness. */
5419 const char *name
= weak_global_object_name
;
5420 const char *file
= main_input_filename
;
5425 file
= input_filename
;
5427 p
= (char *) alloca (7 + strlen (name
) + strlen (file
));
5429 sprintf (p
, "%s%s", name
, file
);
5430 append_random_chars (p
);
5433 buf
= (char *) alloca (sizeof (FILE_FUNCTION_FORMAT
) + strlen (p
)
5436 /* Set up the name of the file-level functions we may need.
5437 Use a global object (which is already required to be unique over
5438 the program) rather than the file name (which imposes extra
5440 sprintf (buf
, FILE_FUNCTION_FORMAT
, type
, p
);
5442 /* Don't need to pull weird characters out of global names. */
5443 if (p
!= first_global_object_name
)
5445 for (p
= buf
+11; *p
; p
++)
5447 #if 0 /* we always want labels, which are valid C++ identifiers (+ `$') */
5448 #ifndef ASM_IDENTIFY_GCC /* this is required if `.' is invalid -- k. raeburn */
5452 #ifndef NO_DOLLAR_IN_LABEL /* this for `$'; unlikely, but... -- kr */
5455 #ifndef NO_DOT_IN_LABEL /* this for `.'; unlikely, but... */
5463 return get_identifier (buf
);
5466 /* If KIND=='I', return a suitable global initializer (constructor) name.
5467 If KIND=='D', return a suitable global clean-up (destructor) name. */
5470 get_file_function_name (kind
)
5478 return get_file_function_name_long (p
);
5481 /* Expand (the constant part of) a SET_TYPE CONSTRUCTOR node.
5482 The result is placed in BUFFER (which has length BIT_SIZE),
5483 with one bit in each char ('\000' or '\001').
5485 If the constructor is constant, NULL_TREE is returned.
5486 Otherwise, a TREE_LIST of the non-constant elements is emitted. */
5489 get_set_constructor_bits (init
, buffer
, bit_size
)
5496 HOST_WIDE_INT domain_min
5497 = TREE_INT_CST_LOW (TYPE_MIN_VALUE (TYPE_DOMAIN (TREE_TYPE (init
))));
5498 tree non_const_bits
= NULL_TREE
;
5499 for (i
= 0; i
< bit_size
; i
++)
5502 for (vals
= TREE_OPERAND (init
, 1);
5503 vals
!= NULL_TREE
; vals
= TREE_CHAIN (vals
))
5505 if (TREE_CODE (TREE_VALUE (vals
)) != INTEGER_CST
5506 || (TREE_PURPOSE (vals
) != NULL_TREE
5507 && TREE_CODE (TREE_PURPOSE (vals
)) != INTEGER_CST
))
5509 = tree_cons (TREE_PURPOSE (vals
), TREE_VALUE (vals
), non_const_bits
);
5510 else if (TREE_PURPOSE (vals
) != NULL_TREE
)
5512 /* Set a range of bits to ones. */
5513 HOST_WIDE_INT lo_index
5514 = TREE_INT_CST_LOW (TREE_PURPOSE (vals
)) - domain_min
;
5515 HOST_WIDE_INT hi_index
5516 = TREE_INT_CST_LOW (TREE_VALUE (vals
)) - domain_min
;
5518 if (lo_index
< 0 || lo_index
>= bit_size
5519 || hi_index
< 0 || hi_index
>= bit_size
)
5521 for ( ; lo_index
<= hi_index
; lo_index
++)
5522 buffer
[lo_index
] = 1;
5526 /* Set a single bit to one. */
5528 = TREE_INT_CST_LOW (TREE_VALUE (vals
)) - domain_min
;
5529 if (index
< 0 || index
>= bit_size
)
5531 error ("invalid initializer for bit string");
5537 return non_const_bits
;
5540 /* Expand (the constant part of) a SET_TYPE CONSTRUCTOR node.
5541 The result is placed in BUFFER (which is an array of bytes).
5542 If the constructor is constant, NULL_TREE is returned.
5543 Otherwise, a TREE_LIST of the non-constant elements is emitted. */
5546 get_set_constructor_bytes (init
, buffer
, wd_size
)
5548 unsigned char *buffer
;
5552 int set_word_size
= BITS_PER_UNIT
;
5553 int bit_size
= wd_size
* set_word_size
;
5555 unsigned char *bytep
= buffer
;
5556 char *bit_buffer
= (char *) alloca(bit_size
);
5557 tree non_const_bits
= get_set_constructor_bits (init
, bit_buffer
, bit_size
);
5559 for (i
= 0; i
< wd_size
; i
++)
5562 for (i
= 0; i
< bit_size
; i
++)
5566 if (BYTES_BIG_ENDIAN
)
5567 *bytep
|= (1 << (set_word_size
- 1 - bit_pos
));
5569 *bytep
|= 1 << bit_pos
;
5572 if (bit_pos
>= set_word_size
)
5573 bit_pos
= 0, bytep
++;
5575 return non_const_bits
;
5578 #if defined ENABLE_TREE_CHECKING && (GCC_VERSION >= 2007)
5579 /* Complain that the tree code of NODE does not match the expected CODE.
5580 FILE, LINE, and FUNCTION are of the caller. */
5582 tree_check_failed (node
, code
, file
, line
, function
)
5584 enum tree_code code
;
5587 const char *function
;
5589 error ("Tree check: expected %s, have %s",
5590 tree_code_name
[code
], tree_code_name
[TREE_CODE (node
)]);
5591 fancy_abort (file
, line
, function
);
5594 /* Similar to above, except that we check for a class of tree
5595 code, given in CL. */
5597 tree_class_check_failed (node
, cl
, file
, line
, function
)
5602 const char *function
;
5604 error ("Tree check: expected class '%c', have '%c' (%s)",
5605 cl
, TREE_CODE_CLASS (TREE_CODE (node
)),
5606 tree_code_name
[TREE_CODE (node
)]);
5607 fancy_abort (file
, line
, function
);
5610 #endif /* ENABLE_TREE_CHECKING */
5612 /* Return the alias set for T, which may be either a type or an
5619 if (! flag_strict_aliasing
|| lang_get_alias_set
== 0)
5620 /* If we're not doing any lanaguage-specific alias analysis, just
5621 assume everything aliases everything else. */
5624 return (*lang_get_alias_set
) (t
);
5627 /* Return a brand-new alias set. */
5632 static int last_alias_set
;
5634 if (flag_strict_aliasing
)
5635 return ++last_alias_set
;
5640 #ifndef CHAR_TYPE_SIZE
5641 #define CHAR_TYPE_SIZE BITS_PER_UNIT
5644 #ifndef SHORT_TYPE_SIZE
5645 #define SHORT_TYPE_SIZE (BITS_PER_UNIT * MIN ((UNITS_PER_WORD + 1) / 2, 2))
5648 #ifndef INT_TYPE_SIZE
5649 #define INT_TYPE_SIZE BITS_PER_WORD
5652 #ifndef LONG_TYPE_SIZE
5653 #define LONG_TYPE_SIZE BITS_PER_WORD
5656 #ifndef LONG_LONG_TYPE_SIZE
5657 #define LONG_LONG_TYPE_SIZE (BITS_PER_WORD * 2)
5660 #ifndef FLOAT_TYPE_SIZE
5661 #define FLOAT_TYPE_SIZE BITS_PER_WORD
5664 #ifndef DOUBLE_TYPE_SIZE
5665 #define DOUBLE_TYPE_SIZE (BITS_PER_WORD * 2)
5668 #ifndef LONG_DOUBLE_TYPE_SIZE
5669 #define LONG_DOUBLE_TYPE_SIZE (BITS_PER_WORD * 2)
5672 /* Create nodes for all integer types (and error_mark_node) using the sizes
5673 of C datatypes. The caller should call set_sizetype soon after calling
5674 this function to select one of the types as sizetype. */
5677 build_common_tree_nodes (signed_char
)
5680 error_mark_node
= make_node (ERROR_MARK
);
5681 TREE_TYPE (error_mark_node
) = error_mark_node
;
5683 initialize_sizetypes ();
5685 /* Define both `signed char' and `unsigned char'. */
5686 signed_char_type_node
= make_signed_type (CHAR_TYPE_SIZE
);
5687 unsigned_char_type_node
= make_unsigned_type (CHAR_TYPE_SIZE
);
5689 /* Define `char', which is like either `signed char' or `unsigned char'
5690 but not the same as either. */
5693 ? make_signed_type (CHAR_TYPE_SIZE
)
5694 : make_unsigned_type (CHAR_TYPE_SIZE
));
5696 short_integer_type_node
= make_signed_type (SHORT_TYPE_SIZE
);
5697 short_unsigned_type_node
= make_unsigned_type (SHORT_TYPE_SIZE
);
5698 integer_type_node
= make_signed_type (INT_TYPE_SIZE
);
5699 unsigned_type_node
= make_unsigned_type (INT_TYPE_SIZE
);
5700 long_integer_type_node
= make_signed_type (LONG_TYPE_SIZE
);
5701 long_unsigned_type_node
= make_unsigned_type (LONG_TYPE_SIZE
);
5702 long_long_integer_type_node
= make_signed_type (LONG_LONG_TYPE_SIZE
);
5703 long_long_unsigned_type_node
= make_unsigned_type (LONG_LONG_TYPE_SIZE
);
5705 intQI_type_node
= make_signed_type (GET_MODE_BITSIZE (QImode
));
5706 intHI_type_node
= make_signed_type (GET_MODE_BITSIZE (HImode
));
5707 intSI_type_node
= make_signed_type (GET_MODE_BITSIZE (SImode
));
5708 intDI_type_node
= make_signed_type (GET_MODE_BITSIZE (DImode
));
5709 intTI_type_node
= make_signed_type (GET_MODE_BITSIZE (TImode
));
5711 unsigned_intQI_type_node
= make_unsigned_type (GET_MODE_BITSIZE (QImode
));
5712 unsigned_intHI_type_node
= make_unsigned_type (GET_MODE_BITSIZE (HImode
));
5713 unsigned_intSI_type_node
= make_unsigned_type (GET_MODE_BITSIZE (SImode
));
5714 unsigned_intDI_type_node
= make_unsigned_type (GET_MODE_BITSIZE (DImode
));
5715 unsigned_intTI_type_node
= make_unsigned_type (GET_MODE_BITSIZE (TImode
));
5718 /* Call this function after calling build_common_tree_nodes and set_sizetype.
5719 It will create several other common tree nodes. */
5722 build_common_tree_nodes_2 (short_double
)
5725 /* Define these next since types below may used them. */
5726 integer_zero_node
= build_int_2 (0, 0);
5727 integer_one_node
= build_int_2 (1, 0);
5729 size_zero_node
= size_int (0);
5730 size_one_node
= size_int (1);
5731 bitsize_zero_node
= bitsize_int (0);
5732 bitsize_one_node
= bitsize_int (1);
5733 bitsize_unit_node
= bitsize_int (BITS_PER_UNIT
);
5735 void_type_node
= make_node (VOID_TYPE
);
5736 layout_type (void_type_node
);
5738 /* We are not going to have real types in C with less than byte alignment,
5739 so we might as well not have any types that claim to have it. */
5740 TYPE_ALIGN (void_type_node
) = BITS_PER_UNIT
;
5742 null_pointer_node
= build_int_2 (0, 0);
5743 TREE_TYPE (null_pointer_node
) = build_pointer_type (void_type_node
);
5744 layout_type (TREE_TYPE (null_pointer_node
));
5746 ptr_type_node
= build_pointer_type (void_type_node
);
5748 = build_pointer_type (build_type_variant (void_type_node
, 1, 0));
5750 float_type_node
= make_node (REAL_TYPE
);
5751 TYPE_PRECISION (float_type_node
) = FLOAT_TYPE_SIZE
;
5752 layout_type (float_type_node
);
5754 double_type_node
= make_node (REAL_TYPE
);
5756 TYPE_PRECISION (double_type_node
) = FLOAT_TYPE_SIZE
;
5758 TYPE_PRECISION (double_type_node
) = DOUBLE_TYPE_SIZE
;
5759 layout_type (double_type_node
);
5761 long_double_type_node
= make_node (REAL_TYPE
);
5762 TYPE_PRECISION (long_double_type_node
) = LONG_DOUBLE_TYPE_SIZE
;
5763 layout_type (long_double_type_node
);
5765 complex_integer_type_node
= make_node (COMPLEX_TYPE
);
5766 TREE_TYPE (complex_integer_type_node
) = integer_type_node
;
5767 layout_type (complex_integer_type_node
);
5769 complex_float_type_node
= make_node (COMPLEX_TYPE
);
5770 TREE_TYPE (complex_float_type_node
) = float_type_node
;
5771 layout_type (complex_float_type_node
);
5773 complex_double_type_node
= make_node (COMPLEX_TYPE
);
5774 TREE_TYPE (complex_double_type_node
) = double_type_node
;
5775 layout_type (complex_double_type_node
);
5777 complex_long_double_type_node
= make_node (COMPLEX_TYPE
);
5778 TREE_TYPE (complex_long_double_type_node
) = long_double_type_node
;
5779 layout_type (complex_long_double_type_node
);
5781 #ifdef BUILD_VA_LIST_TYPE
5782 BUILD_VA_LIST_TYPE(va_list_type_node
);
5784 va_list_type_node
= ptr_type_node
;