1 /* Subroutines shared by all languages that are variants of C.
2 Copyright (C) 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000,
3 2001, 2002 Free Software Foundation, Inc.
5 This file is part of GCC.
7 GCC is free software; you can redistribute it and/or modify it under
8 the terms of the GNU General Public License as published by the Free
9 Software Foundation; either version 2, or (at your option) any later
12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
13 WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
17 You should have received a copy of the GNU General Public License
18 along with GCC; see the file COPYING. If not, write to the Free
19 Software Foundation, 59 Temple Place - Suite 330, Boston, MA
33 #include "tree-inline.h"
34 #include "diagnostic.h"
40 #include "langhooks.h"
41 cpp_reader *parse_in; /* Declared in c-lex.h. */
43 #undef WCHAR_TYPE_SIZE
44 #define WCHAR_TYPE_SIZE TYPE_PRECISION (wchar_type_node)
46 /* We let tm.h override the types used here, to handle trivial differences
47 such as the choice of unsigned int or long unsigned int for size_t.
48 When machines start needing nontrivial differences in the size type,
49 it would be best to do something here to figure out automatically
50 from other information what type to use. */
53 #define SIZE_TYPE "long unsigned int"
57 #define WCHAR_TYPE "int"
61 #define PTRDIFF_TYPE "long int"
65 #define WINT_TYPE "unsigned int"
69 #define INTMAX_TYPE ((INT_TYPE_SIZE == LONG_LONG_TYPE_SIZE) \
71 : ((LONG_TYPE_SIZE == LONG_LONG_TYPE_SIZE) \
77 #define UINTMAX_TYPE ((INT_TYPE_SIZE == LONG_LONG_TYPE_SIZE) \
79 : ((LONG_TYPE_SIZE == LONG_LONG_TYPE_SIZE) \
80 ? "long unsigned int" \
81 : "long long unsigned int"))
84 /* The variant of the C language being processed. */
86 enum c_language_kind c_language;
88 /* The following symbols are subsumed in the c_global_trees array, and
89 listed here individually for documentation purposes.
91 INTEGER_TYPE and REAL_TYPE nodes for the standard data types.
93 tree short_integer_type_node;
94 tree long_integer_type_node;
95 tree long_long_integer_type_node;
97 tree short_unsigned_type_node;
98 tree long_unsigned_type_node;
99 tree long_long_unsigned_type_node;
101 tree boolean_type_node;
102 tree boolean_false_node;
103 tree boolean_true_node;
105 tree ptrdiff_type_node;
107 tree unsigned_char_type_node;
108 tree signed_char_type_node;
109 tree wchar_type_node;
110 tree signed_wchar_type_node;
111 tree unsigned_wchar_type_node;
113 tree float_type_node;
114 tree double_type_node;
115 tree long_double_type_node;
117 tree complex_integer_type_node;
118 tree complex_float_type_node;
119 tree complex_double_type_node;
120 tree complex_long_double_type_node;
122 tree intQI_type_node;
123 tree intHI_type_node;
124 tree intSI_type_node;
125 tree intDI_type_node;
126 tree intTI_type_node;
128 tree unsigned_intQI_type_node;
129 tree unsigned_intHI_type_node;
130 tree unsigned_intSI_type_node;
131 tree unsigned_intDI_type_node;
132 tree unsigned_intTI_type_node;
134 tree widest_integer_literal_type_node;
135 tree widest_unsigned_literal_type_node;
137 Nodes for types `void *' and `const void *'.
139 tree ptr_type_node, const_ptr_type_node;
141 Nodes for types `char *' and `const char *'.
143 tree string_type_node, const_string_type_node;
145 Type `char[SOMENUMBER]'.
146 Used when an array of char is needed and the size is irrelevant.
148 tree char_array_type_node;
150 Type `int[SOMENUMBER]' or something like it.
151 Used when an array of int needed and the size is irrelevant.
153 tree int_array_type_node;
155 Type `wchar_t[SOMENUMBER]' or something like it.
156 Used when a wide string literal is created.
158 tree wchar_array_type_node;
160 Type `int ()' -- used for implicit declaration of functions.
162 tree default_function_type;
164 A VOID_TYPE node, packaged in a TREE_LIST.
168 The lazily created VAR_DECLs for __FUNCTION__, __PRETTY_FUNCTION__,
169 and __func__. (C doesn't generate __FUNCTION__ and__PRETTY_FUNCTION__
170 VAR_DECLS, but C++ does.)
172 tree function_name_decl_node;
173 tree pretty_function_name_decl_node;
174 tree c99_function_name_decl_node;
176 Stack of nested function name VAR_DECLs.
178 tree saved_function_name_decls;
182 tree c_global_trees[CTI_MAX];
184 /* Nonzero if prepreprocessing only. */
185 int flag_preprocess_only;
187 /* Nonzero means don't recognize the non-ANSI builtin functions. */
191 /* Nonzero means don't recognize the non-ANSI builtin functions.
194 int flag_no_nonansi_builtin;
196 /* Nonzero means give `double' the same size as `float'. */
198 int flag_short_double;
200 /* Nonzero means give `wchar_t' the same size as `short'. */
202 int flag_short_wchar;
204 /* Nonzero means warn about possible violations of sequence point rules. */
206 int warn_sequence_point;
208 /* Nonzero means to warn about compile-time division by zero. */
209 int warn_div_by_zero = 1;
211 /* The elements of `ridpointers' are identifier nodes for the reserved
212 type names and storage classes. It is indexed by a RID_... value. */
215 tree (*make_fname_decl) PARAMS ((tree, int));
217 /* If non-NULL, the address of a language-specific function that
218 returns 1 for language-specific statement codes. */
219 int (*lang_statement_code_p) PARAMS ((enum tree_code));
221 /* If non-NULL, the address of a language-specific function that takes
222 any action required right before expand_function_end is called. */
223 void (*lang_expand_function_end) PARAMS ((void));
225 /* Nonzero means the expression being parsed will never be evaluated.
226 This is a count, since unevaluated expressions can nest. */
229 /* Information about how a function name is generated. */
232 tree *const decl; /* pointer to the VAR_DECL. */
233 const unsigned rid; /* RID number for the identifier. */
234 const int pretty; /* How pretty is it? */
237 /* The three ways of getting then name of the current function. */
239 const struct fname_var_t fname_vars[] =
241 /* C99 compliant __func__, must be first. */
242 {&c99_function_name_decl_node, RID_C99_FUNCTION_NAME, 0},
243 /* GCC __FUNCTION__ compliant. */
244 {&function_name_decl_node, RID_FUNCTION_NAME, 0},
245 /* GCC __PRETTY_FUNCTION__ compliant. */
246 {&pretty_function_name_decl_node, RID_PRETTY_FUNCTION_NAME, 1},
250 static int constant_fits_type_p PARAMS ((tree, tree));
252 /* Keep a stack of if statements. We record the number of compound
253 statements seen up to the if keyword, as well as the line number
254 and file of the if. If a potentially ambiguous else is seen, that
255 fact is recorded; the warning is issued when we can be sure that
256 the enclosing if statement does not have an else branch. */
266 static if_elt *if_stack;
268 /* Amount of space in the if statement stack. */
269 static int if_stack_space = 0;
272 static int if_stack_pointer = 0;
274 /* Record the start of an if-then, and record the start of it
275 for ambiguous else detection.
277 COND is the condition for the if-then statement.
279 IF_STMT is the statement node that has already been created for
280 this if-then statement. It is created before parsing the
281 condition to keep line number information accurate. */
284 c_expand_start_cond (cond, compstmt_count, if_stmt)
289 /* Make sure there is enough space on the stack. */
290 if (if_stack_space == 0)
293 if_stack = (if_elt *) xmalloc (10 * sizeof (if_elt));
295 else if (if_stack_space == if_stack_pointer)
297 if_stack_space += 10;
298 if_stack = (if_elt *) xrealloc (if_stack, if_stack_space * sizeof (if_elt));
301 IF_COND (if_stmt) = cond;
304 /* Record this if statement. */
305 if_stack[if_stack_pointer].compstmt_count = compstmt_count;
306 if_stack[if_stack_pointer].file = input_filename;
307 if_stack[if_stack_pointer].line = lineno;
308 if_stack[if_stack_pointer].needs_warning = 0;
309 if_stack[if_stack_pointer].if_stmt = if_stmt;
313 /* Called after the then-clause for an if-statement is processed. */
318 tree if_stmt = if_stack[if_stack_pointer - 1].if_stmt;
319 RECHAIN_STMTS (if_stmt, THEN_CLAUSE (if_stmt));
322 /* Record the end of an if-then. Optionally warn if a nested
323 if statement had an ambiguous else clause. */
329 if (if_stack[if_stack_pointer].needs_warning)
330 warning_with_file_and_line (if_stack[if_stack_pointer].file,
331 if_stack[if_stack_pointer].line,
332 "suggest explicit braces to avoid ambiguous `else'");
333 last_expr_type = NULL_TREE;
336 /* Called between the then-clause and the else-clause
337 of an if-then-else. */
340 c_expand_start_else ()
342 /* An ambiguous else warning must be generated for the enclosing if
343 statement, unless we see an else branch for that one, too. */
345 && if_stack_pointer > 1
346 && (if_stack[if_stack_pointer - 1].compstmt_count
347 == if_stack[if_stack_pointer - 2].compstmt_count))
348 if_stack[if_stack_pointer - 2].needs_warning = 1;
350 /* Even if a nested if statement had an else branch, it can't be
351 ambiguous if this one also has an else. So don't warn in that
352 case. Also don't warn for any if statements nested in this else. */
353 if_stack[if_stack_pointer - 1].needs_warning = 0;
354 if_stack[if_stack_pointer - 1].compstmt_count--;
357 /* Called after the else-clause for an if-statement is processed. */
362 tree if_stmt = if_stack[if_stack_pointer - 1].if_stmt;
363 RECHAIN_STMTS (if_stmt, ELSE_CLAUSE (if_stmt));
366 /* Begin an if-statement. Returns a newly created IF_STMT if
369 Unlike the C++ front-end, we do not call add_stmt here; it is
370 probably safe to do so, but I am not very familiar with this
371 code so I am being extra careful not to change its behavior
372 beyond what is strictly necessary for correctness. */
378 r = build_stmt (IF_STMT, NULL_TREE, NULL_TREE, NULL_TREE);
382 /* Begin a while statement. Returns a newly created WHILE_STMT if
385 Unlike the C++ front-end, we do not call add_stmt here; it is
386 probably safe to do so, but I am not very familiar with this
387 code so I am being extra careful not to change its behavior
388 beyond what is strictly necessary for correctness. */
391 c_begin_while_stmt ()
394 r = build_stmt (WHILE_STMT, NULL_TREE, NULL_TREE);
399 c_finish_while_stmt_cond (cond, while_stmt)
403 WHILE_COND (while_stmt) = cond;
406 /* Push current bindings for the function name VAR_DECLS. */
412 tree saved = NULL_TREE;
414 for (ix = 0; fname_vars[ix].decl; ix++)
416 tree decl = *fname_vars[ix].decl;
420 saved = tree_cons (decl, build_int_2 (ix, 0), saved);
421 *fname_vars[ix].decl = NULL_TREE;
424 if (saved || saved_function_name_decls)
425 /* Normally they'll have been NULL, so only push if we've got a
426 stack, or they are non-NULL. */
427 saved_function_name_decls = tree_cons (saved, NULL_TREE,
428 saved_function_name_decls);
431 /* Finish up the current bindings, adding them into the
432 current function's statement tree. This is done by wrapping the
433 function's body in a COMPOUND_STMT containing these decls too. This
434 must be done _before_ finish_stmt_tree is called. If there is no
435 current function, we must be at file scope and no statements are
436 involved. Pop the previous bindings. */
439 finish_fname_decls ()
442 tree body = NULL_TREE;
443 tree stack = saved_function_name_decls;
445 for (; stack && TREE_VALUE (stack); stack = TREE_CHAIN (stack))
446 body = chainon (TREE_VALUE (stack), body);
450 /* They were called into existence, so add to statement tree. */
451 body = chainon (body,
452 TREE_CHAIN (DECL_SAVED_TREE (current_function_decl)));
453 body = build_stmt (COMPOUND_STMT, body);
455 COMPOUND_STMT_NO_SCOPE (body) = 1;
456 TREE_CHAIN (DECL_SAVED_TREE (current_function_decl)) = body;
459 for (ix = 0; fname_vars[ix].decl; ix++)
460 *fname_vars[ix].decl = NULL_TREE;
464 /* We had saved values, restore them. */
467 for (saved = TREE_PURPOSE (stack); saved; saved = TREE_CHAIN (saved))
469 tree decl = TREE_PURPOSE (saved);
470 unsigned ix = TREE_INT_CST_LOW (TREE_VALUE (saved));
472 *fname_vars[ix].decl = decl;
474 stack = TREE_CHAIN (stack);
476 saved_function_name_decls = stack;
479 /* Return the text name of the current function, suitable prettified
483 fname_as_string (pretty_p)
486 const char *name = NULL;
489 name = (current_function_decl
490 ? (*lang_hooks.decl_printable_name) (current_function_decl, 2)
492 else if (current_function_decl && DECL_NAME (current_function_decl))
493 name = IDENTIFIER_POINTER (DECL_NAME (current_function_decl));
499 /* Return the text name of the current function, formatted as
500 required by the supplied RID value. */
508 for (ix = 0; fname_vars[ix].decl; ix++)
509 if (fname_vars[ix].rid == rid)
511 return fname_as_string (fname_vars[ix].pretty);
514 /* Return the VAR_DECL for a const char array naming the current
515 function. If the VAR_DECL has not yet been created, create it
516 now. RID indicates how it should be formatted and IDENTIFIER_NODE
517 ID is its name (unfortunately C and C++ hold the RID values of
518 keywords in different places, so we can't derive RID from ID in
519 this language independent code. */
527 tree decl = NULL_TREE;
529 for (ix = 0; fname_vars[ix].decl; ix++)
530 if (fname_vars[ix].rid == rid)
533 decl = *fname_vars[ix].decl;
536 tree saved_last_tree = last_tree;
538 decl = (*make_fname_decl) (id, fname_vars[ix].pretty);
539 if (last_tree != saved_last_tree)
541 /* We created some statement tree for the decl. This belongs
542 at the start of the function, so remove it now and reinsert
543 it after the function is complete. */
544 tree stmts = TREE_CHAIN (saved_last_tree);
546 TREE_CHAIN (saved_last_tree) = NULL_TREE;
547 last_tree = saved_last_tree;
548 saved_function_name_decls = tree_cons (decl, stmts,
549 saved_function_name_decls);
551 *fname_vars[ix].decl = decl;
553 if (!ix && !current_function_decl)
554 pedwarn_with_decl (decl, "`%s' is not defined outside of function scope");
559 /* Given a chain of STRING_CST nodes,
560 concatenate them into one STRING_CST
561 and give it a suitable array-of-chars data type. */
564 combine_strings (strings)
571 int wchar_bytes = TYPE_PRECISION (wchar_type_node) / BITS_PER_UNIT;
573 const int nchars_max = flag_isoc99 ? 4095 : 509;
575 if (TREE_CHAIN (strings))
577 /* More than one in the chain, so concatenate. */
580 /* Don't include the \0 at the end of each substring,
581 except for the last one.
582 Count wide strings and ordinary strings separately. */
583 for (t = strings; t; t = TREE_CHAIN (t))
585 if (TREE_TYPE (t) == wchar_array_type_node)
587 wide_length += (TREE_STRING_LENGTH (t) - wchar_bytes);
592 length += (TREE_STRING_LENGTH (t) - 1);
593 if (C_ARTIFICIAL_STRING_P (t) && !in_system_header)
594 warning ("concatenation of string literals with __FUNCTION__ is deprecated. This feature will be removed in future");
598 /* If anything is wide, the non-wides will be converted,
599 which makes them take more space. */
601 length = length * wchar_bytes + wide_length;
605 /* Copy the individual strings into the new combined string.
606 If the combined string is wide, convert the chars to ints
607 for any individual strings that are not wide. */
610 for (t = strings; t; t = TREE_CHAIN (t))
612 int len = (TREE_STRING_LENGTH (t)
613 - ((TREE_TYPE (t) == wchar_array_type_node)
615 if ((TREE_TYPE (t) == wchar_array_type_node) == wide_flag)
617 memcpy (q, TREE_STRING_POINTER (t), len);
623 for (i = 0; i < len; i++)
625 if (BYTES_BIG_ENDIAN)
627 for (j=0; j<(WCHAR_TYPE_SIZE / BITS_PER_UNIT)-1; j++)
629 *q++ = TREE_STRING_POINTER (t)[i];
633 *q++ = TREE_STRING_POINTER (t)[i];
634 for (j=0; j<(WCHAR_TYPE_SIZE / BITS_PER_UNIT)-1; j++)
643 for (i = 0; i < wchar_bytes; i++)
649 value = build_string (length, p);
654 length = TREE_STRING_LENGTH (value);
655 if (TREE_TYPE (value) == wchar_array_type_node)
659 /* Compute the number of elements, for the array type. */
660 nchars = wide_flag ? length / wchar_bytes : length;
662 if (pedantic && nchars - 1 > nchars_max && c_language == clk_c)
663 pedwarn ("string length `%d' is greater than the length `%d' ISO C%d compilers are required to support",
664 nchars - 1, nchars_max, flag_isoc99 ? 99 : 89);
666 /* Create the array type for the string constant.
667 -Wwrite-strings says make the string constant an array of const char
668 so that copying it to a non-const pointer will get a warning.
669 For C++, this is the standard behavior. */
670 if (flag_const_strings && ! flag_writable_strings)
673 = build_type_variant (wide_flag ? wchar_type_node : char_type_node,
676 = build_array_type (elements,
677 build_index_type (build_int_2 (nchars - 1, 0)));
681 = build_array_type (wide_flag ? wchar_type_node : char_type_node,
682 build_index_type (build_int_2 (nchars - 1, 0)));
684 TREE_CONSTANT (value) = 1;
685 TREE_READONLY (value) = ! flag_writable_strings;
686 TREE_STATIC (value) = 1;
690 static int is_valid_printf_arglist PARAMS ((tree));
691 static rtx c_expand_builtin PARAMS ((tree, rtx, enum machine_mode, enum expand_modifier));
692 static rtx c_expand_builtin_printf PARAMS ((tree, rtx, enum machine_mode,
693 enum expand_modifier, int, int));
694 static rtx c_expand_builtin_fprintf PARAMS ((tree, rtx, enum machine_mode,
695 enum expand_modifier, int, int));
697 /* Print a warning if a constant expression had overflow in folding.
698 Invoke this function on every expression that the language
699 requires to be a constant expression.
700 Note the ANSI C standard says it is erroneous for a
701 constant expression to overflow. */
704 constant_expression_warning (value)
707 if ((TREE_CODE (value) == INTEGER_CST || TREE_CODE (value) == REAL_CST
708 || TREE_CODE (value) == VECTOR_CST
709 || TREE_CODE (value) == COMPLEX_CST)
710 && TREE_CONSTANT_OVERFLOW (value) && pedantic)
711 pedwarn ("overflow in constant expression");
714 /* Print a warning if an expression had overflow in folding.
715 Invoke this function on every expression that
716 (1) appears in the source code, and
717 (2) might be a constant expression that overflowed, and
718 (3) is not already checked by convert_and_check;
719 however, do not invoke this function on operands of explicit casts. */
722 overflow_warning (value)
725 if ((TREE_CODE (value) == INTEGER_CST
726 || (TREE_CODE (value) == COMPLEX_CST
727 && TREE_CODE (TREE_REALPART (value)) == INTEGER_CST))
728 && TREE_OVERFLOW (value))
730 TREE_OVERFLOW (value) = 0;
731 if (skip_evaluation == 0)
732 warning ("integer overflow in expression");
734 else if ((TREE_CODE (value) == REAL_CST
735 || (TREE_CODE (value) == COMPLEX_CST
736 && TREE_CODE (TREE_REALPART (value)) == REAL_CST))
737 && TREE_OVERFLOW (value))
739 TREE_OVERFLOW (value) = 0;
740 if (skip_evaluation == 0)
741 warning ("floating point overflow in expression");
743 else if (TREE_CODE (value) == VECTOR_CST && TREE_OVERFLOW (value))
745 TREE_OVERFLOW (value) = 0;
746 if (skip_evaluation == 0)
747 warning ("vector overflow in expression");
751 /* Print a warning if a large constant is truncated to unsigned,
752 or if -Wconversion is used and a constant < 0 is converted to unsigned.
753 Invoke this function on every expression that might be implicitly
754 converted to an unsigned type. */
757 unsigned_conversion_warning (result, operand)
758 tree result, operand;
760 tree type = TREE_TYPE (result);
762 if (TREE_CODE (operand) == INTEGER_CST
763 && TREE_CODE (type) == INTEGER_TYPE
764 && TREE_UNSIGNED (type)
765 && skip_evaluation == 0
766 && !int_fits_type_p (operand, type))
768 if (!int_fits_type_p (operand, c_common_signed_type (type)))
769 /* This detects cases like converting -129 or 256 to unsigned char. */
770 warning ("large integer implicitly truncated to unsigned type");
771 else if (warn_conversion)
772 warning ("negative integer implicitly converted to unsigned type");
776 /* Nonzero if constant C has a value that is permissible
777 for type TYPE (an INTEGER_TYPE). */
780 constant_fits_type_p (c, type)
783 if (TREE_CODE (c) == INTEGER_CST)
784 return int_fits_type_p (c, type);
786 c = convert (type, c);
787 return !TREE_OVERFLOW (c);
790 /* Convert EXPR to TYPE, warning about conversion problems with constants.
791 Invoke this function on every expression that is converted implicitly,
792 i.e. because of language rules and not because of an explicit cast. */
795 convert_and_check (type, expr)
798 tree t = convert (type, expr);
799 if (TREE_CODE (t) == INTEGER_CST)
801 if (TREE_OVERFLOW (t))
803 TREE_OVERFLOW (t) = 0;
805 /* Do not diagnose overflow in a constant expression merely
806 because a conversion overflowed. */
807 TREE_CONSTANT_OVERFLOW (t) = TREE_CONSTANT_OVERFLOW (expr);
809 /* No warning for converting 0x80000000 to int. */
810 if (!(TREE_UNSIGNED (type) < TREE_UNSIGNED (TREE_TYPE (expr))
811 && TREE_CODE (TREE_TYPE (expr)) == INTEGER_TYPE
812 && TYPE_PRECISION (type) == TYPE_PRECISION (TREE_TYPE (expr))))
813 /* If EXPR fits in the unsigned version of TYPE,
814 don't warn unless pedantic. */
816 || TREE_UNSIGNED (type)
817 || ! constant_fits_type_p (expr,
818 c_common_unsigned_type (type)))
819 && skip_evaluation == 0)
820 warning ("overflow in implicit constant conversion");
823 unsigned_conversion_warning (t, expr);
828 /* A node in a list that describes references to variables (EXPR), which are
829 either read accesses if WRITER is zero, or write accesses, in which case
830 WRITER is the parent of EXPR. */
837 /* Used to implement a cache the results of a call to verify_tree. We only
838 use this for SAVE_EXPRs. */
841 struct tlist_cache *next;
842 struct tlist *cache_before_sp;
843 struct tlist *cache_after_sp;
847 /* Obstack to use when allocating tlist structures, and corresponding
849 static struct obstack tlist_obstack;
850 static char *tlist_firstobj = 0;
852 /* Keep track of the identifiers we've warned about, so we can avoid duplicate
854 static struct tlist *warned_ids;
855 /* SAVE_EXPRs need special treatment. We process them only once and then
856 cache the results. */
857 static struct tlist_cache *save_expr_cache;
859 static void add_tlist PARAMS ((struct tlist **, struct tlist *, tree, int));
860 static void merge_tlist PARAMS ((struct tlist **, struct tlist *, int));
861 static void verify_tree PARAMS ((tree, struct tlist **, struct tlist **, tree));
862 static int warning_candidate_p PARAMS ((tree));
863 static void warn_for_collisions PARAMS ((struct tlist *));
864 static void warn_for_collisions_1 PARAMS ((tree, tree, struct tlist *, int));
865 static struct tlist *new_tlist PARAMS ((struct tlist *, tree, tree));
866 static void verify_sequence_points PARAMS ((tree));
868 /* Create a new struct tlist and fill in its fields. */
869 static struct tlist *
870 new_tlist (next, t, writer)
876 l = (struct tlist *) obstack_alloc (&tlist_obstack, sizeof *l);
883 /* Add duplicates of the nodes found in ADD to the list *TO. If EXCLUDE_WRITER
884 is nonnull, we ignore any node we find which has a writer equal to it. */
887 add_tlist (to, add, exclude_writer, copy)
895 struct tlist *next = add->next;
898 if (! exclude_writer || add->writer != exclude_writer)
899 *to = copy ? new_tlist (*to, add->expr, add->writer) : add;
904 /* Merge the nodes of ADD into TO. This merging process is done so that for
905 each variable that already exists in TO, no new node is added; however if
906 there is a write access recorded in ADD, and an occurrence on TO is only
907 a read access, then the occurrence in TO will be modified to record the
911 merge_tlist (to, add, copy)
916 struct tlist **end = to;
925 struct tlist *next = add->next;
927 for (tmp2 = *to; tmp2; tmp2 = tmp2->next)
928 if (tmp2->expr == add->expr)
932 tmp2->writer = add->writer;
936 *end = copy ? add : new_tlist (NULL, add->expr, add->writer);
944 /* WRITTEN is a variable, WRITER is its parent. Warn if any of the variable
945 references in list LIST conflict with it, excluding reads if ONLY writers
949 warn_for_collisions_1 (written, writer, list, only_writes)
950 tree written, writer;
956 /* Avoid duplicate warnings. */
957 for (tmp = warned_ids; tmp; tmp = tmp->next)
958 if (tmp->expr == written)
963 if (list->expr == written
964 && list->writer != writer
965 && (! only_writes || list->writer))
967 warned_ids = new_tlist (warned_ids, written, NULL_TREE);
968 warning ("operation on `%s' may be undefined",
969 IDENTIFIER_POINTER (DECL_NAME (list->expr)));
975 /* Given a list LIST of references to variables, find whether any of these
976 can cause conflicts due to missing sequence points. */
979 warn_for_collisions (list)
984 for (tmp = list; tmp; tmp = tmp->next)
987 warn_for_collisions_1 (tmp->expr, tmp->writer, list, 0);
991 /* Return nonzero if X is a tree that can be verified by the sequence point
994 warning_candidate_p (x)
997 return TREE_CODE (x) == VAR_DECL || TREE_CODE (x) == PARM_DECL;
1000 /* Walk the tree X, and record accesses to variables. If X is written by the
1001 parent tree, WRITER is the parent.
1002 We store accesses in one of the two lists: PBEFORE_SP, and PNO_SP. If this
1003 expression or its only operand forces a sequence point, then everything up
1004 to the sequence point is stored in PBEFORE_SP. Everything else gets stored
1006 Once we return, we will have emitted warnings if any subexpression before
1007 such a sequence point could be undefined. On a higher level, however, the
1008 sequence point may not be relevant, and we'll merge the two lists.
1010 Example: (b++, a) + b;
1011 The call that processes the COMPOUND_EXPR will store the increment of B
1012 in PBEFORE_SP, and the use of A in PNO_SP. The higher-level call that
1013 processes the PLUS_EXPR will need to merge the two lists so that
1014 eventually, all accesses end up on the same list (and we'll warn about the
1015 unordered subexpressions b++ and b.
1017 A note on merging. If we modify the former example so that our expression
1020 care must be taken not simply to add all three expressions into the final
1021 PNO_SP list. The function merge_tlist takes care of that by merging the
1022 before-SP list of the COMPOUND_EXPR into its after-SP list in a special
1023 way, so that no more than one access to B is recorded. */
1026 verify_tree (x, pbefore_sp, pno_sp, writer)
1028 struct tlist **pbefore_sp, **pno_sp;
1031 struct tlist *tmp_before, *tmp_nosp, *tmp_list2, *tmp_list3;
1032 enum tree_code code;
1035 /* X may be NULL if it is the operand of an empty statement expression
1041 code = TREE_CODE (x);
1042 class = TREE_CODE_CLASS (code);
1044 if (warning_candidate_p (x))
1046 *pno_sp = new_tlist (*pno_sp, x, writer);
1056 case TRUTH_ANDIF_EXPR:
1057 case TRUTH_ORIF_EXPR:
1058 tmp_before = tmp_nosp = tmp_list3 = 0;
1059 verify_tree (TREE_OPERAND (x, 0), &tmp_before, &tmp_nosp, NULL_TREE);
1060 warn_for_collisions (tmp_nosp);
1061 merge_tlist (pbefore_sp, tmp_before, 0);
1062 merge_tlist (pbefore_sp, tmp_nosp, 0);
1063 verify_tree (TREE_OPERAND (x, 1), &tmp_list3, pno_sp, NULL_TREE);
1064 merge_tlist (pbefore_sp, tmp_list3, 0);
1068 tmp_before = tmp_list2 = 0;
1069 verify_tree (TREE_OPERAND (x, 0), &tmp_before, &tmp_list2, NULL_TREE);
1070 warn_for_collisions (tmp_list2);
1071 merge_tlist (pbefore_sp, tmp_before, 0);
1072 merge_tlist (pbefore_sp, tmp_list2, 1);
1074 tmp_list3 = tmp_nosp = 0;
1075 verify_tree (TREE_OPERAND (x, 1), &tmp_list3, &tmp_nosp, NULL_TREE);
1076 warn_for_collisions (tmp_nosp);
1077 merge_tlist (pbefore_sp, tmp_list3, 0);
1079 tmp_list3 = tmp_list2 = 0;
1080 verify_tree (TREE_OPERAND (x, 2), &tmp_list3, &tmp_list2, NULL_TREE);
1081 warn_for_collisions (tmp_list2);
1082 merge_tlist (pbefore_sp, tmp_list3, 0);
1083 /* Rather than add both tmp_nosp and tmp_list2, we have to merge the
1084 two first, to avoid warning for (a ? b++ : b++). */
1085 merge_tlist (&tmp_nosp, tmp_list2, 0);
1086 add_tlist (pno_sp, tmp_nosp, NULL_TREE, 0);
1089 case PREDECREMENT_EXPR:
1090 case PREINCREMENT_EXPR:
1091 case POSTDECREMENT_EXPR:
1092 case POSTINCREMENT_EXPR:
1093 verify_tree (TREE_OPERAND (x, 0), pno_sp, pno_sp, x);
1097 tmp_before = tmp_nosp = tmp_list3 = 0;
1098 verify_tree (TREE_OPERAND (x, 1), &tmp_before, &tmp_nosp, NULL_TREE);
1099 verify_tree (TREE_OPERAND (x, 0), &tmp_list3, &tmp_list3, x);
1100 /* Expressions inside the LHS are not ordered wrt. the sequence points
1101 in the RHS. Example:
1103 Despite the fact that the modification of "a" is in the before_sp
1104 list (tmp_before), it conflicts with the use of "a" in the LHS.
1105 We can handle this by adding the contents of tmp_list3
1106 to those of tmp_before, and redoing the collision warnings for that
1108 add_tlist (&tmp_before, tmp_list3, x, 1);
1109 warn_for_collisions (tmp_before);
1110 /* Exclude the LHS itself here; we first have to merge it into the
1111 tmp_nosp list. This is done to avoid warning for "a = a"; if we
1112 didn't exclude the LHS, we'd get it twice, once as a read and once
1114 add_tlist (pno_sp, tmp_list3, x, 0);
1115 warn_for_collisions_1 (TREE_OPERAND (x, 0), x, tmp_nosp, 1);
1117 merge_tlist (pbefore_sp, tmp_before, 0);
1118 if (warning_candidate_p (TREE_OPERAND (x, 0)))
1119 merge_tlist (&tmp_nosp, new_tlist (NULL, TREE_OPERAND (x, 0), x), 0);
1120 add_tlist (pno_sp, tmp_nosp, NULL_TREE, 1);
1124 /* We need to warn about conflicts among arguments and conflicts between
1125 args and the function address. Side effects of the function address,
1126 however, are not ordered by the sequence point of the call. */
1127 tmp_before = tmp_nosp = tmp_list2 = tmp_list3 = 0;
1128 verify_tree (TREE_OPERAND (x, 0), &tmp_before, &tmp_nosp, NULL_TREE);
1129 if (TREE_OPERAND (x, 1))
1130 verify_tree (TREE_OPERAND (x, 1), &tmp_list2, &tmp_list3, NULL_TREE);
1131 merge_tlist (&tmp_list3, tmp_list2, 0);
1132 add_tlist (&tmp_before, tmp_list3, NULL_TREE, 0);
1133 add_tlist (&tmp_before, tmp_nosp, NULL_TREE, 0);
1134 warn_for_collisions (tmp_before);
1135 add_tlist (pbefore_sp, tmp_before, NULL_TREE, 0);
1139 /* Scan all the list, e.g. indices of multi dimensional array. */
1142 tmp_before = tmp_nosp = 0;
1143 verify_tree (TREE_VALUE (x), &tmp_before, &tmp_nosp, NULL_TREE);
1144 merge_tlist (&tmp_nosp, tmp_before, 0);
1145 add_tlist (pno_sp, tmp_nosp, NULL_TREE, 0);
1152 struct tlist_cache *t;
1153 for (t = save_expr_cache; t; t = t->next)
1159 t = (struct tlist_cache *) obstack_alloc (&tlist_obstack,
1161 t->next = save_expr_cache;
1163 save_expr_cache = t;
1165 tmp_before = tmp_nosp = 0;
1166 verify_tree (TREE_OPERAND (x, 0), &tmp_before, &tmp_nosp, NULL_TREE);
1167 warn_for_collisions (tmp_nosp);
1172 struct tlist *t = tmp_nosp;
1174 merge_tlist (&tmp_list3, t, 0);
1176 t->cache_before_sp = tmp_before;
1177 t->cache_after_sp = tmp_list3;
1179 merge_tlist (pbefore_sp, t->cache_before_sp, 1);
1180 add_tlist (pno_sp, t->cache_after_sp, NULL_TREE, 1);
1189 if (first_rtl_op (code) == 0)
1191 x = TREE_OPERAND (x, 0);
1207 int max = first_rtl_op (TREE_CODE (x));
1208 for (lp = 0; lp < max; lp++)
1210 tmp_before = tmp_nosp = 0;
1211 verify_tree (TREE_OPERAND (x, lp), &tmp_before, &tmp_nosp, NULL_TREE);
1212 merge_tlist (&tmp_nosp, tmp_before, 0);
1213 add_tlist (pno_sp, tmp_nosp, NULL_TREE, 0);
1220 /* Try to warn for undefined behaviour in EXPR due to missing sequence
1224 verify_sequence_points (expr)
1227 struct tlist *before_sp = 0, *after_sp = 0;
1230 save_expr_cache = 0;
1231 if (tlist_firstobj == 0)
1233 gcc_obstack_init (&tlist_obstack);
1234 tlist_firstobj = obstack_alloc (&tlist_obstack, 0);
1237 verify_tree (expr, &before_sp, &after_sp, 0);
1238 warn_for_collisions (after_sp);
1239 obstack_free (&tlist_obstack, tlist_firstobj);
1243 c_expand_expr_stmt (expr)
1246 /* Do default conversion if safe and possibly important,
1247 in case within ({...}). */
1248 if ((TREE_CODE (TREE_TYPE (expr)) == ARRAY_TYPE
1249 && (flag_isoc99 || lvalue_p (expr)))
1250 || TREE_CODE (TREE_TYPE (expr)) == FUNCTION_TYPE)
1251 expr = default_conversion (expr);
1253 if (warn_sequence_point)
1254 verify_sequence_points (expr);
1256 if (TREE_TYPE (expr) != error_mark_node
1257 && !COMPLETE_OR_VOID_TYPE_P (TREE_TYPE (expr))
1258 && TREE_CODE (TREE_TYPE (expr)) != ARRAY_TYPE)
1259 error ("expression statement has incomplete type");
1261 last_expr_type = TREE_TYPE (expr);
1262 return add_stmt (build_stmt (EXPR_STMT, expr));
1265 /* Validate the expression after `case' and apply default promotions. */
1268 check_case_value (value)
1271 if (value == NULL_TREE)
1274 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
1275 STRIP_TYPE_NOPS (value);
1276 /* In C++, the following is allowed:
1279 switch (...) { case i: ... }
1281 So, we try to reduce the VALUE to a constant that way. */
1282 if (c_language == clk_cplusplus)
1284 value = decl_constant_value (value);
1285 STRIP_TYPE_NOPS (value);
1286 value = fold (value);
1289 if (TREE_CODE (value) != INTEGER_CST
1290 && value != error_mark_node)
1292 error ("case label does not reduce to an integer constant");
1293 value = error_mark_node;
1296 /* Promote char or short to int. */
1297 value = default_conversion (value);
1299 constant_expression_warning (value);
1304 /* Return an integer type with BITS bits of precision,
1305 that is unsigned if UNSIGNEDP is nonzero, otherwise signed. */
1308 c_common_type_for_size (bits, unsignedp)
1312 if (bits == TYPE_PRECISION (integer_type_node))
1313 return unsignedp ? unsigned_type_node : integer_type_node;
1315 if (bits == TYPE_PRECISION (signed_char_type_node))
1316 return unsignedp ? unsigned_char_type_node : signed_char_type_node;
1318 if (bits == TYPE_PRECISION (short_integer_type_node))
1319 return unsignedp ? short_unsigned_type_node : short_integer_type_node;
1321 if (bits == TYPE_PRECISION (long_integer_type_node))
1322 return unsignedp ? long_unsigned_type_node : long_integer_type_node;
1324 if (bits == TYPE_PRECISION (long_long_integer_type_node))
1325 return (unsignedp ? long_long_unsigned_type_node
1326 : long_long_integer_type_node);
1328 if (bits == TYPE_PRECISION (widest_integer_literal_type_node))
1329 return (unsignedp ? widest_unsigned_literal_type_node
1330 : widest_integer_literal_type_node);
1332 if (bits <= TYPE_PRECISION (intQI_type_node))
1333 return unsignedp ? unsigned_intQI_type_node : intQI_type_node;
1335 if (bits <= TYPE_PRECISION (intHI_type_node))
1336 return unsignedp ? unsigned_intHI_type_node : intHI_type_node;
1338 if (bits <= TYPE_PRECISION (intSI_type_node))
1339 return unsignedp ? unsigned_intSI_type_node : intSI_type_node;
1341 if (bits <= TYPE_PRECISION (intDI_type_node))
1342 return unsignedp ? unsigned_intDI_type_node : intDI_type_node;
1347 /* Return a data type that has machine mode MODE.
1348 If the mode is an integer,
1349 then UNSIGNEDP selects between signed and unsigned types. */
1352 c_common_type_for_mode (mode, unsignedp)
1353 enum machine_mode mode;
1356 if (mode == TYPE_MODE (integer_type_node))
1357 return unsignedp ? unsigned_type_node : integer_type_node;
1359 if (mode == TYPE_MODE (signed_char_type_node))
1360 return unsignedp ? unsigned_char_type_node : signed_char_type_node;
1362 if (mode == TYPE_MODE (short_integer_type_node))
1363 return unsignedp ? short_unsigned_type_node : short_integer_type_node;
1365 if (mode == TYPE_MODE (long_integer_type_node))
1366 return unsignedp ? long_unsigned_type_node : long_integer_type_node;
1368 if (mode == TYPE_MODE (long_long_integer_type_node))
1369 return unsignedp ? long_long_unsigned_type_node : long_long_integer_type_node;
1371 if (mode == TYPE_MODE (widest_integer_literal_type_node))
1372 return unsignedp ? widest_unsigned_literal_type_node
1373 : widest_integer_literal_type_node;
1376 return unsignedp ? unsigned_intQI_type_node : intQI_type_node;
1379 return unsignedp ? unsigned_intHI_type_node : intHI_type_node;
1382 return unsignedp ? unsigned_intSI_type_node : intSI_type_node;
1385 return unsignedp ? unsigned_intDI_type_node : intDI_type_node;
1387 #if HOST_BITS_PER_WIDE_INT >= 64
1388 if (mode == TYPE_MODE (intTI_type_node))
1389 return unsignedp ? unsigned_intTI_type_node : intTI_type_node;
1392 if (mode == TYPE_MODE (float_type_node))
1393 return float_type_node;
1395 if (mode == TYPE_MODE (double_type_node))
1396 return double_type_node;
1398 if (mode == TYPE_MODE (long_double_type_node))
1399 return long_double_type_node;
1401 if (mode == TYPE_MODE (build_pointer_type (char_type_node)))
1402 return build_pointer_type (char_type_node);
1404 if (mode == TYPE_MODE (build_pointer_type (integer_type_node)))
1405 return build_pointer_type (integer_type_node);
1407 #ifdef VECTOR_MODE_SUPPORTED_P
1408 if (VECTOR_MODE_SUPPORTED_P (mode))
1413 return unsignedp ? unsigned_V16QI_type_node : V16QI_type_node;
1415 return unsignedp ? unsigned_V8HI_type_node : V8HI_type_node;
1417 return unsignedp ? unsigned_V4SI_type_node : V4SI_type_node;
1419 return unsignedp ? unsigned_V2SI_type_node : V2SI_type_node;
1421 return unsignedp ? unsigned_V4HI_type_node : V4HI_type_node;
1423 return unsignedp ? unsigned_V8QI_type_node : V8QI_type_node;
1425 return V16SF_type_node;
1427 return V4SF_type_node;
1429 return V2SF_type_node;
1439 /* Return an unsigned type the same as TYPE in other respects. */
1441 c_common_unsigned_type (type)
1444 tree type1 = TYPE_MAIN_VARIANT (type);
1445 if (type1 == signed_char_type_node || type1 == char_type_node)
1446 return unsigned_char_type_node;
1447 if (type1 == integer_type_node)
1448 return unsigned_type_node;
1449 if (type1 == short_integer_type_node)
1450 return short_unsigned_type_node;
1451 if (type1 == long_integer_type_node)
1452 return long_unsigned_type_node;
1453 if (type1 == long_long_integer_type_node)
1454 return long_long_unsigned_type_node;
1455 if (type1 == widest_integer_literal_type_node)
1456 return widest_unsigned_literal_type_node;
1457 #if HOST_BITS_PER_WIDE_INT >= 64
1458 if (type1 == intTI_type_node)
1459 return unsigned_intTI_type_node;
1461 if (type1 == intDI_type_node)
1462 return unsigned_intDI_type_node;
1463 if (type1 == intSI_type_node)
1464 return unsigned_intSI_type_node;
1465 if (type1 == intHI_type_node)
1466 return unsigned_intHI_type_node;
1467 if (type1 == intQI_type_node)
1468 return unsigned_intQI_type_node;
1470 return c_common_signed_or_unsigned_type (1, type);
1473 /* Return a signed type the same as TYPE in other respects. */
1476 c_common_signed_type (type)
1479 tree type1 = TYPE_MAIN_VARIANT (type);
1480 if (type1 == unsigned_char_type_node || type1 == char_type_node)
1481 return signed_char_type_node;
1482 if (type1 == unsigned_type_node)
1483 return integer_type_node;
1484 if (type1 == short_unsigned_type_node)
1485 return short_integer_type_node;
1486 if (type1 == long_unsigned_type_node)
1487 return long_integer_type_node;
1488 if (type1 == long_long_unsigned_type_node)
1489 return long_long_integer_type_node;
1490 if (type1 == widest_unsigned_literal_type_node)
1491 return widest_integer_literal_type_node;
1492 #if HOST_BITS_PER_WIDE_INT >= 64
1493 if (type1 == unsigned_intTI_type_node)
1494 return intTI_type_node;
1496 if (type1 == unsigned_intDI_type_node)
1497 return intDI_type_node;
1498 if (type1 == unsigned_intSI_type_node)
1499 return intSI_type_node;
1500 if (type1 == unsigned_intHI_type_node)
1501 return intHI_type_node;
1502 if (type1 == unsigned_intQI_type_node)
1503 return intQI_type_node;
1505 return c_common_signed_or_unsigned_type (0, type);
1508 /* Return a type the same as TYPE except unsigned or
1509 signed according to UNSIGNEDP. */
1512 c_common_signed_or_unsigned_type (unsignedp, type)
1516 if (! INTEGRAL_TYPE_P (type)
1517 || TREE_UNSIGNED (type) == unsignedp)
1520 if (TYPE_PRECISION (type) == TYPE_PRECISION (signed_char_type_node))
1521 return unsignedp ? unsigned_char_type_node : signed_char_type_node;
1522 if (TYPE_PRECISION (type) == TYPE_PRECISION (integer_type_node))
1523 return unsignedp ? unsigned_type_node : integer_type_node;
1524 if (TYPE_PRECISION (type) == TYPE_PRECISION (short_integer_type_node))
1525 return unsignedp ? short_unsigned_type_node : short_integer_type_node;
1526 if (TYPE_PRECISION (type) == TYPE_PRECISION (long_integer_type_node))
1527 return unsignedp ? long_unsigned_type_node : long_integer_type_node;
1528 if (TYPE_PRECISION (type) == TYPE_PRECISION (long_long_integer_type_node))
1529 return (unsignedp ? long_long_unsigned_type_node
1530 : long_long_integer_type_node);
1531 if (TYPE_PRECISION (type) == TYPE_PRECISION (widest_integer_literal_type_node))
1532 return (unsignedp ? widest_unsigned_literal_type_node
1533 : widest_integer_literal_type_node);
1535 #if HOST_BITS_PER_WIDE_INT >= 64
1536 if (TYPE_PRECISION (type) == TYPE_PRECISION (intTI_type_node))
1537 return unsignedp ? unsigned_intTI_type_node : intTI_type_node;
1539 if (TYPE_PRECISION (type) == TYPE_PRECISION (intDI_type_node))
1540 return unsignedp ? unsigned_intDI_type_node : intDI_type_node;
1541 if (TYPE_PRECISION (type) == TYPE_PRECISION (intSI_type_node))
1542 return unsignedp ? unsigned_intSI_type_node : intSI_type_node;
1543 if (TYPE_PRECISION (type) == TYPE_PRECISION (intHI_type_node))
1544 return unsignedp ? unsigned_intHI_type_node : intHI_type_node;
1545 if (TYPE_PRECISION (type) == TYPE_PRECISION (intQI_type_node))
1546 return unsignedp ? unsigned_intQI_type_node : intQI_type_node;
1551 /* Return the minimum number of bits needed to represent VALUE in a
1552 signed or unsigned type, UNSIGNEDP says which. */
1555 min_precision (value, unsignedp)
1561 /* If the value is negative, compute its negative minus 1. The latter
1562 adjustment is because the absolute value of the largest negative value
1563 is one larger than the largest positive value. This is equivalent to
1564 a bit-wise negation, so use that operation instead. */
1566 if (tree_int_cst_sgn (value) < 0)
1567 value = fold (build1 (BIT_NOT_EXPR, TREE_TYPE (value), value));
1569 /* Return the number of bits needed, taking into account the fact
1570 that we need one more bit for a signed than unsigned type. */
1572 if (integer_zerop (value))
1575 log = tree_floor_log2 (value);
1577 return log + 1 + ! unsignedp;
1580 /* Print an error message for invalid operands to arith operation CODE.
1581 NOP_EXPR is used as a special case (see truthvalue_conversion). */
1584 binary_op_error (code)
1585 enum tree_code code;
1592 error ("invalid truth-value expression");
1596 opname = "+"; break;
1598 opname = "-"; break;
1600 opname = "*"; break;
1602 opname = "max"; break;
1604 opname = "min"; break;
1606 opname = "=="; break;
1608 opname = "!="; break;
1610 opname = "<="; break;
1612 opname = ">="; break;
1614 opname = "<"; break;
1616 opname = ">"; break;
1618 opname = "<<"; break;
1620 opname = ">>"; break;
1621 case TRUNC_MOD_EXPR:
1622 case FLOOR_MOD_EXPR:
1623 opname = "%"; break;
1624 case TRUNC_DIV_EXPR:
1625 case FLOOR_DIV_EXPR:
1626 opname = "/"; break;
1628 opname = "&"; break;
1630 opname = "|"; break;
1631 case TRUTH_ANDIF_EXPR:
1632 opname = "&&"; break;
1633 case TRUTH_ORIF_EXPR:
1634 opname = "||"; break;
1636 opname = "^"; break;
1639 opname = "rotate"; break;
1641 opname = "unknown"; break;
1643 error ("invalid operands to binary %s", opname);
1646 /* Subroutine of build_binary_op, used for comparison operations.
1647 See if the operands have both been converted from subword integer types
1648 and, if so, perhaps change them both back to their original type.
1649 This function is also responsible for converting the two operands
1650 to the proper common type for comparison.
1652 The arguments of this function are all pointers to local variables
1653 of build_binary_op: OP0_PTR is &OP0, OP1_PTR is &OP1,
1654 RESTYPE_PTR is &RESULT_TYPE and RESCODE_PTR is &RESULTCODE.
1656 If this function returns nonzero, it means that the comparison has
1657 a constant value. What this function returns is an expression for
1661 shorten_compare (op0_ptr, op1_ptr, restype_ptr, rescode_ptr)
1662 tree *op0_ptr, *op1_ptr;
1664 enum tree_code *rescode_ptr;
1667 tree op0 = *op0_ptr;
1668 tree op1 = *op1_ptr;
1669 int unsignedp0, unsignedp1;
1671 tree primop0, primop1;
1672 enum tree_code code = *rescode_ptr;
1674 /* Throw away any conversions to wider types
1675 already present in the operands. */
1677 primop0 = get_narrower (op0, &unsignedp0);
1678 primop1 = get_narrower (op1, &unsignedp1);
1680 /* Handle the case that OP0 does not *contain* a conversion
1681 but it *requires* conversion to FINAL_TYPE. */
1683 if (op0 == primop0 && TREE_TYPE (op0) != *restype_ptr)
1684 unsignedp0 = TREE_UNSIGNED (TREE_TYPE (op0));
1685 if (op1 == primop1 && TREE_TYPE (op1) != *restype_ptr)
1686 unsignedp1 = TREE_UNSIGNED (TREE_TYPE (op1));
1688 /* If one of the operands must be floated, we cannot optimize. */
1689 real1 = TREE_CODE (TREE_TYPE (primop0)) == REAL_TYPE;
1690 real2 = TREE_CODE (TREE_TYPE (primop1)) == REAL_TYPE;
1692 /* If first arg is constant, swap the args (changing operation
1693 so value is preserved), for canonicalization. Don't do this if
1694 the second arg is 0. */
1696 if (TREE_CONSTANT (primop0)
1697 && ! integer_zerop (primop1) && ! real_zerop (primop1))
1700 int temi = unsignedp0;
1708 unsignedp0 = unsignedp1;
1731 *rescode_ptr = code;
1734 /* If comparing an integer against a constant more bits wide,
1735 maybe we can deduce a value of 1 or 0 independent of the data.
1736 Or else truncate the constant now
1737 rather than extend the variable at run time.
1739 This is only interesting if the constant is the wider arg.
1740 Also, it is not safe if the constant is unsigned and the
1741 variable arg is signed, since in this case the variable
1742 would be sign-extended and then regarded as unsigned.
1743 Our technique fails in this case because the lowest/highest
1744 possible unsigned results don't follow naturally from the
1745 lowest/highest possible values of the variable operand.
1746 For just EQ_EXPR and NE_EXPR there is another technique that
1747 could be used: see if the constant can be faithfully represented
1748 in the other operand's type, by truncating it and reextending it
1749 and see if that preserves the constant's value. */
1751 if (!real1 && !real2
1752 && TREE_CODE (primop1) == INTEGER_CST
1753 && TYPE_PRECISION (TREE_TYPE (primop0)) < TYPE_PRECISION (*restype_ptr))
1755 int min_gt, max_gt, min_lt, max_lt;
1756 tree maxval, minval;
1757 /* 1 if comparison is nominally unsigned. */
1758 int unsignedp = TREE_UNSIGNED (*restype_ptr);
1761 type = c_common_signed_or_unsigned_type (unsignedp0,
1762 TREE_TYPE (primop0));
1764 /* If TYPE is an enumeration, then we need to get its min/max
1765 values from it's underlying integral type, not the enumerated
1767 if (TREE_CODE (type) == ENUMERAL_TYPE)
1768 type = c_common_type_for_size (TYPE_PRECISION (type), unsignedp0);
1770 maxval = TYPE_MAX_VALUE (type);
1771 minval = TYPE_MIN_VALUE (type);
1773 if (unsignedp && !unsignedp0)
1774 *restype_ptr = c_common_signed_type (*restype_ptr);
1776 if (TREE_TYPE (primop1) != *restype_ptr)
1777 primop1 = convert (*restype_ptr, primop1);
1778 if (type != *restype_ptr)
1780 minval = convert (*restype_ptr, minval);
1781 maxval = convert (*restype_ptr, maxval);
1784 if (unsignedp && unsignedp0)
1786 min_gt = INT_CST_LT_UNSIGNED (primop1, minval);
1787 max_gt = INT_CST_LT_UNSIGNED (primop1, maxval);
1788 min_lt = INT_CST_LT_UNSIGNED (minval, primop1);
1789 max_lt = INT_CST_LT_UNSIGNED (maxval, primop1);
1793 min_gt = INT_CST_LT (primop1, minval);
1794 max_gt = INT_CST_LT (primop1, maxval);
1795 min_lt = INT_CST_LT (minval, primop1);
1796 max_lt = INT_CST_LT (maxval, primop1);
1800 /* This used to be a switch, but Genix compiler can't handle that. */
1801 if (code == NE_EXPR)
1803 if (max_lt || min_gt)
1804 val = boolean_true_node;
1806 else if (code == EQ_EXPR)
1808 if (max_lt || min_gt)
1809 val = boolean_false_node;
1811 else if (code == LT_EXPR)
1814 val = boolean_true_node;
1816 val = boolean_false_node;
1818 else if (code == GT_EXPR)
1821 val = boolean_true_node;
1823 val = boolean_false_node;
1825 else if (code == LE_EXPR)
1828 val = boolean_true_node;
1830 val = boolean_false_node;
1832 else if (code == GE_EXPR)
1835 val = boolean_true_node;
1837 val = boolean_false_node;
1840 /* If primop0 was sign-extended and unsigned comparison specd,
1841 we did a signed comparison above using the signed type bounds.
1842 But the comparison we output must be unsigned.
1844 Also, for inequalities, VAL is no good; but if the signed
1845 comparison had *any* fixed result, it follows that the
1846 unsigned comparison just tests the sign in reverse
1847 (positive values are LE, negative ones GE).
1848 So we can generate an unsigned comparison
1849 against an extreme value of the signed type. */
1851 if (unsignedp && !unsignedp0)
1858 primop1 = TYPE_MIN_VALUE (type);
1864 primop1 = TYPE_MAX_VALUE (type);
1871 type = c_common_unsigned_type (type);
1874 if (!max_gt && !unsignedp0 && TREE_CODE (primop0) != INTEGER_CST)
1876 /* This is the case of (char)x >?< 0x80, which people used to use
1877 expecting old C compilers to change the 0x80 into -0x80. */
1878 if (val == boolean_false_node)
1879 warning ("comparison is always false due to limited range of data type");
1880 if (val == boolean_true_node)
1881 warning ("comparison is always true due to limited range of data type");
1884 if (!min_lt && unsignedp0 && TREE_CODE (primop0) != INTEGER_CST)
1886 /* This is the case of (unsigned char)x >?< -1 or < 0. */
1887 if (val == boolean_false_node)
1888 warning ("comparison is always false due to limited range of data type");
1889 if (val == boolean_true_node)
1890 warning ("comparison is always true due to limited range of data type");
1895 /* Don't forget to evaluate PRIMOP0 if it has side effects. */
1896 if (TREE_SIDE_EFFECTS (primop0))
1897 return build (COMPOUND_EXPR, TREE_TYPE (val), primop0, val);
1901 /* Value is not predetermined, but do the comparison
1902 in the type of the operand that is not constant.
1903 TYPE is already properly set. */
1905 else if (real1 && real2
1906 && (TYPE_PRECISION (TREE_TYPE (primop0))
1907 == TYPE_PRECISION (TREE_TYPE (primop1))))
1908 type = TREE_TYPE (primop0);
1910 /* If args' natural types are both narrower than nominal type
1911 and both extend in the same manner, compare them
1912 in the type of the wider arg.
1913 Otherwise must actually extend both to the nominal
1914 common type lest different ways of extending
1916 (eg, (short)-1 == (unsigned short)-1 should be 0.) */
1918 else if (unsignedp0 == unsignedp1 && real1 == real2
1919 && TYPE_PRECISION (TREE_TYPE (primop0)) < TYPE_PRECISION (*restype_ptr)
1920 && TYPE_PRECISION (TREE_TYPE (primop1)) < TYPE_PRECISION (*restype_ptr))
1922 type = common_type (TREE_TYPE (primop0), TREE_TYPE (primop1));
1923 type = c_common_signed_or_unsigned_type (unsignedp0
1924 || TREE_UNSIGNED (*restype_ptr),
1926 /* Make sure shorter operand is extended the right way
1927 to match the longer operand. */
1929 = convert (c_common_signed_or_unsigned_type (unsignedp0,
1930 TREE_TYPE (primop0)),
1933 = convert (c_common_signed_or_unsigned_type (unsignedp1,
1934 TREE_TYPE (primop1)),
1939 /* Here we must do the comparison on the nominal type
1940 using the args exactly as we received them. */
1941 type = *restype_ptr;
1945 if (!real1 && !real2 && integer_zerop (primop1)
1946 && TREE_UNSIGNED (*restype_ptr))
1952 /* All unsigned values are >= 0, so we warn if extra warnings
1953 are requested. However, if OP0 is a constant that is
1954 >= 0, the signedness of the comparison isn't an issue,
1955 so suppress the warning. */
1956 if (extra_warnings && !in_system_header
1957 && ! (TREE_CODE (primop0) == INTEGER_CST
1958 && ! TREE_OVERFLOW (convert (c_common_signed_type (type),
1960 warning ("comparison of unsigned expression >= 0 is always true");
1961 value = boolean_true_node;
1965 if (extra_warnings && !in_system_header
1966 && ! (TREE_CODE (primop0) == INTEGER_CST
1967 && ! TREE_OVERFLOW (convert (c_common_signed_type (type),
1969 warning ("comparison of unsigned expression < 0 is always false");
1970 value = boolean_false_node;
1979 /* Don't forget to evaluate PRIMOP0 if it has side effects. */
1980 if (TREE_SIDE_EFFECTS (primop0))
1981 return build (COMPOUND_EXPR, TREE_TYPE (value),
1988 *op0_ptr = convert (type, primop0);
1989 *op1_ptr = convert (type, primop1);
1991 *restype_ptr = boolean_type_node;
1996 /* Return a tree for the sum or difference (RESULTCODE says which)
1997 of pointer PTROP and integer INTOP. */
2000 pointer_int_sum (resultcode, ptrop, intop)
2001 enum tree_code resultcode;
2009 /* The result is a pointer of the same type that is being added. */
2011 tree result_type = TREE_TYPE (ptrop);
2013 if (TREE_CODE (TREE_TYPE (result_type)) == VOID_TYPE)
2015 if (pedantic || warn_pointer_arith)
2016 pedwarn ("pointer of type `void *' used in arithmetic");
2017 size_exp = integer_one_node;
2019 else if (TREE_CODE (TREE_TYPE (result_type)) == FUNCTION_TYPE)
2021 if (pedantic || warn_pointer_arith)
2022 pedwarn ("pointer to a function used in arithmetic");
2023 size_exp = integer_one_node;
2025 else if (TREE_CODE (TREE_TYPE (result_type)) == METHOD_TYPE)
2027 if (pedantic || warn_pointer_arith)
2028 pedwarn ("pointer to member function used in arithmetic");
2029 size_exp = integer_one_node;
2031 else if (TREE_CODE (TREE_TYPE (result_type)) == OFFSET_TYPE)
2033 if (pedantic || warn_pointer_arith)
2034 pedwarn ("pointer to a member used in arithmetic");
2035 size_exp = integer_one_node;
2038 size_exp = size_in_bytes (TREE_TYPE (result_type));
2040 /* If what we are about to multiply by the size of the elements
2041 contains a constant term, apply distributive law
2042 and multiply that constant term separately.
2043 This helps produce common subexpressions. */
2045 if ((TREE_CODE (intop) == PLUS_EXPR || TREE_CODE (intop) == MINUS_EXPR)
2046 && ! TREE_CONSTANT (intop)
2047 && TREE_CONSTANT (TREE_OPERAND (intop, 1))
2048 && TREE_CONSTANT (size_exp)
2049 /* If the constant comes from pointer subtraction,
2050 skip this optimization--it would cause an error. */
2051 && TREE_CODE (TREE_TYPE (TREE_OPERAND (intop, 0))) == INTEGER_TYPE
2052 /* If the constant is unsigned, and smaller than the pointer size,
2053 then we must skip this optimization. This is because it could cause
2054 an overflow error if the constant is negative but INTOP is not. */
2055 && (! TREE_UNSIGNED (TREE_TYPE (intop))
2056 || (TYPE_PRECISION (TREE_TYPE (intop))
2057 == TYPE_PRECISION (TREE_TYPE (ptrop)))))
2059 enum tree_code subcode = resultcode;
2060 tree int_type = TREE_TYPE (intop);
2061 if (TREE_CODE (intop) == MINUS_EXPR)
2062 subcode = (subcode == PLUS_EXPR ? MINUS_EXPR : PLUS_EXPR);
2063 /* Convert both subexpression types to the type of intop,
2064 because weird cases involving pointer arithmetic
2065 can result in a sum or difference with different type args. */
2066 ptrop = build_binary_op (subcode, ptrop,
2067 convert (int_type, TREE_OPERAND (intop, 1)), 1);
2068 intop = convert (int_type, TREE_OPERAND (intop, 0));
2071 /* Convert the integer argument to a type the same size as sizetype
2072 so the multiply won't overflow spuriously. */
2074 if (TYPE_PRECISION (TREE_TYPE (intop)) != TYPE_PRECISION (sizetype)
2075 || TREE_UNSIGNED (TREE_TYPE (intop)) != TREE_UNSIGNED (sizetype))
2076 intop = convert (c_common_type_for_size (TYPE_PRECISION (sizetype),
2077 TREE_UNSIGNED (sizetype)), intop);
2079 /* Replace the integer argument with a suitable product by the object size.
2080 Do this multiplication as signed, then convert to the appropriate
2081 pointer type (actually unsigned integral). */
2083 intop = convert (result_type,
2084 build_binary_op (MULT_EXPR, intop,
2085 convert (TREE_TYPE (intop), size_exp), 1));
2087 /* Create the sum or difference. */
2089 result = build (resultcode, result_type, ptrop, intop);
2091 folded = fold (result);
2092 if (folded == result)
2093 TREE_CONSTANT (folded) = TREE_CONSTANT (ptrop) & TREE_CONSTANT (intop);
2097 /* Prepare expr to be an argument of a TRUTH_NOT_EXPR,
2098 or validate its data type for an `if' or `while' statement or ?..: exp.
2100 This preparation consists of taking the ordinary
2101 representation of an expression expr and producing a valid tree
2102 boolean expression describing whether expr is nonzero. We could
2103 simply always do build_binary_op (NE_EXPR, expr, boolean_false_node, 1),
2104 but we optimize comparisons, &&, ||, and !.
2106 The resulting type should always be `boolean_type_node'. */
2109 truthvalue_conversion (expr)
2112 if (TREE_CODE (expr) == ERROR_MARK)
2115 #if 0 /* This appears to be wrong for C++. */
2116 /* These really should return error_mark_node after 2.4 is stable.
2117 But not all callers handle ERROR_MARK properly. */
2118 switch (TREE_CODE (TREE_TYPE (expr)))
2121 error ("struct type value used where scalar is required");
2122 return boolean_false_node;
2125 error ("union type value used where scalar is required");
2126 return boolean_false_node;
2129 error ("array type value used where scalar is required");
2130 return boolean_false_node;
2137 switch (TREE_CODE (expr))
2140 case NE_EXPR: case LE_EXPR: case GE_EXPR: case LT_EXPR: case GT_EXPR:
2141 case TRUTH_ANDIF_EXPR:
2142 case TRUTH_ORIF_EXPR:
2143 case TRUTH_AND_EXPR:
2145 case TRUTH_XOR_EXPR:
2146 case TRUTH_NOT_EXPR:
2147 TREE_TYPE (expr) = boolean_type_node;
2154 return integer_zerop (expr) ? boolean_false_node : boolean_true_node;
2157 return real_zerop (expr) ? boolean_false_node : boolean_true_node;
2160 /* If we are taking the address of an external decl, it might be zero
2161 if it is weak, so we cannot optimize. */
2162 if (DECL_P (TREE_OPERAND (expr, 0))
2163 && DECL_EXTERNAL (TREE_OPERAND (expr, 0)))
2166 if (TREE_SIDE_EFFECTS (TREE_OPERAND (expr, 0)))
2167 return build (COMPOUND_EXPR, boolean_type_node,
2168 TREE_OPERAND (expr, 0), boolean_true_node);
2170 return boolean_true_node;
2173 return build_binary_op ((TREE_SIDE_EFFECTS (TREE_OPERAND (expr, 1))
2174 ? TRUTH_OR_EXPR : TRUTH_ORIF_EXPR),
2175 truthvalue_conversion (TREE_OPERAND (expr, 0)),
2176 truthvalue_conversion (TREE_OPERAND (expr, 1)),
2183 /* These don't change whether an object is non-zero or zero. */
2184 return truthvalue_conversion (TREE_OPERAND (expr, 0));
2188 /* These don't change whether an object is zero or non-zero, but
2189 we can't ignore them if their second arg has side-effects. */
2190 if (TREE_SIDE_EFFECTS (TREE_OPERAND (expr, 1)))
2191 return build (COMPOUND_EXPR, boolean_type_node, TREE_OPERAND (expr, 1),
2192 truthvalue_conversion (TREE_OPERAND (expr, 0)));
2194 return truthvalue_conversion (TREE_OPERAND (expr, 0));
2197 /* Distribute the conversion into the arms of a COND_EXPR. */
2198 return fold (build (COND_EXPR, boolean_type_node, TREE_OPERAND (expr, 0),
2199 truthvalue_conversion (TREE_OPERAND (expr, 1)),
2200 truthvalue_conversion (TREE_OPERAND (expr, 2))));
2203 /* Don't cancel the effect of a CONVERT_EXPR from a REFERENCE_TYPE,
2204 since that affects how `default_conversion' will behave. */
2205 if (TREE_CODE (TREE_TYPE (expr)) == REFERENCE_TYPE
2206 || TREE_CODE (TREE_TYPE (TREE_OPERAND (expr, 0))) == REFERENCE_TYPE)
2208 /* fall through... */
2210 /* If this is widening the argument, we can ignore it. */
2211 if (TYPE_PRECISION (TREE_TYPE (expr))
2212 >= TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (expr, 0))))
2213 return truthvalue_conversion (TREE_OPERAND (expr, 0));
2217 /* Perhaps reduce (x - y) != 0 to (x != y). The expressions
2218 aren't guaranteed to the be same for modes that can represent
2219 infinity, since if x and y are both +infinity, or both
2220 -infinity, then x - y is not a number.
2222 Note that this transformation is safe when x or y is NaN.
2223 (x - y) is then NaN, and both (x - y) != 0 and x != y will
2225 if (HONOR_INFINITIES (TYPE_MODE (TREE_TYPE (TREE_OPERAND (expr, 0)))))
2227 /* fall through... */
2229 /* This and MINUS_EXPR can be changed into a comparison of the
2231 if (TREE_TYPE (TREE_OPERAND (expr, 0))
2232 == TREE_TYPE (TREE_OPERAND (expr, 1)))
2233 return build_binary_op (NE_EXPR, TREE_OPERAND (expr, 0),
2234 TREE_OPERAND (expr, 1), 1);
2235 return build_binary_op (NE_EXPR, TREE_OPERAND (expr, 0),
2236 fold (build1 (NOP_EXPR,
2237 TREE_TYPE (TREE_OPERAND (expr, 0)),
2238 TREE_OPERAND (expr, 1))), 1);
2241 if (integer_onep (TREE_OPERAND (expr, 1))
2242 && TREE_TYPE (expr) != boolean_type_node)
2243 /* Using convert here would cause infinite recursion. */
2244 return build1 (NOP_EXPR, boolean_type_node, expr);
2248 if (warn_parentheses && C_EXP_ORIGINAL_CODE (expr) == MODIFY_EXPR)
2249 warning ("suggest parentheses around assignment used as truth value");
2256 if (TREE_CODE (TREE_TYPE (expr)) == COMPLEX_TYPE)
2258 tree tem = save_expr (expr);
2259 return (build_binary_op
2260 ((TREE_SIDE_EFFECTS (expr)
2261 ? TRUTH_OR_EXPR : TRUTH_ORIF_EXPR),
2262 truthvalue_conversion (build_unary_op (REALPART_EXPR, tem, 0)),
2263 truthvalue_conversion (build_unary_op (IMAGPART_EXPR, tem, 0)),
2267 return build_binary_op (NE_EXPR, expr, integer_zero_node, 1);
2270 static tree builtin_function_2 PARAMS ((const char *, const char *, tree, tree,
2271 int, enum built_in_class, int, int,
2274 /* Make a variant type in the proper way for C/C++, propagating qualifiers
2275 down to the element type of an array. */
2278 c_build_qualified_type (type, type_quals)
2282 /* A restrict-qualified pointer type must be a pointer to object or
2283 incomplete type. Note that the use of POINTER_TYPE_P also allows
2284 REFERENCE_TYPEs, which is appropriate for C++. Unfortunately,
2285 the C++ front-end also use POINTER_TYPE for pointer-to-member
2286 values, so even though it should be illegal to use `restrict'
2287 with such an entity we don't flag that here. Thus, special case
2288 code for that case is required in the C++ front-end. */
2289 if ((type_quals & TYPE_QUAL_RESTRICT)
2290 && (!POINTER_TYPE_P (type)
2291 || !C_TYPE_OBJECT_OR_INCOMPLETE_P (TREE_TYPE (type))))
2293 error ("invalid use of `restrict'");
2294 type_quals &= ~TYPE_QUAL_RESTRICT;
2297 if (TREE_CODE (type) == ARRAY_TYPE)
2298 return build_array_type (c_build_qualified_type (TREE_TYPE (type),
2300 TYPE_DOMAIN (type));
2301 return build_qualified_type (type, type_quals);
2304 /* Apply the TYPE_QUALS to the new DECL. */
2307 c_apply_type_quals_to_decl (type_quals, decl)
2311 if ((type_quals & TYPE_QUAL_CONST)
2312 || (TREE_TYPE (decl)
2313 && TREE_CODE (TREE_TYPE (decl)) == REFERENCE_TYPE))
2314 TREE_READONLY (decl) = 1;
2315 if (type_quals & TYPE_QUAL_VOLATILE)
2317 TREE_SIDE_EFFECTS (decl) = 1;
2318 TREE_THIS_VOLATILE (decl) = 1;
2320 if (type_quals & TYPE_QUAL_RESTRICT)
2322 if (!TREE_TYPE (decl)
2323 || !POINTER_TYPE_P (TREE_TYPE (decl))
2324 || !C_TYPE_OBJECT_OR_INCOMPLETE_P (TREE_TYPE (TREE_TYPE (decl))))
2325 error ("invalid use of `restrict'");
2326 else if (flag_strict_aliasing)
2327 /* Indicate we need to make a unique alias set for this pointer.
2328 We can't do it here because it might be pointing to an
2330 DECL_POINTER_ALIAS_SET (decl) = -2;
2334 /* Return the typed-based alias set for T, which may be an expression
2335 or a type. Return -1 if we don't do anything special. */
2338 c_common_get_alias_set (t)
2343 /* We know nothing about vector types */
2344 if (TREE_CODE (t) == VECTOR_TYPE)
2347 /* Permit type-punning when accessing a union, provided the access
2348 is directly through the union. For example, this code does not
2349 permit taking the address of a union member and then storing
2350 through it. Even the type-punning allowed here is a GCC
2351 extension, albeit a common and useful one; the C standard says
2352 that such accesses have implementation-defined behavior. */
2354 TREE_CODE (u) == COMPONENT_REF || TREE_CODE (u) == ARRAY_REF;
2355 u = TREE_OPERAND (u, 0))
2356 if (TREE_CODE (u) == COMPONENT_REF
2357 && TREE_CODE (TREE_TYPE (TREE_OPERAND (u, 0))) == UNION_TYPE)
2360 /* If this is a char *, the ANSI C standard says it can alias
2361 anything. Note that all references need do this. */
2362 if (TREE_CODE_CLASS (TREE_CODE (t)) == 'r'
2363 && TREE_CODE (TREE_TYPE (t)) == INTEGER_TYPE
2364 && TYPE_PRECISION (TREE_TYPE (t)) == TYPE_PRECISION (char_type_node))
2367 /* That's all the expressions we handle specially. */
2371 /* The C standard specifically allows aliasing between signed and
2372 unsigned variants of the same type. We treat the signed
2373 variant as canonical. */
2374 if (TREE_CODE (t) == INTEGER_TYPE && TREE_UNSIGNED (t))
2376 tree t1 = c_common_signed_type (t);
2378 /* t1 == t can happen for boolean nodes which are always unsigned. */
2380 return get_alias_set (t1);
2382 else if (POINTER_TYPE_P (t))
2386 /* Unfortunately, there is no canonical form of a pointer type.
2387 In particular, if we have `typedef int I', then `int *', and
2388 `I *' are different types. So, we have to pick a canonical
2389 representative. We do this below.
2391 Technically, this approach is actually more conservative that
2392 it needs to be. In particular, `const int *' and `int *'
2393 should be in different alias sets, according to the C and C++
2394 standard, since their types are not the same, and so,
2395 technically, an `int **' and `const int **' cannot point at
2398 But, the standard is wrong. In particular, this code is
2403 const int* const* cipp = &ipp;
2405 And, it doesn't make sense for that to be legal unless you
2406 can dereference IPP and CIPP. So, we ignore cv-qualifiers on
2407 the pointed-to types. This issue has been reported to the
2409 t1 = build_type_no_quals (t);
2411 return get_alias_set (t1);
2417 /* Implement the __alignof keyword: Return the minimum required
2418 alignment of TYPE, measured in bytes. */
2424 enum tree_code code = TREE_CODE (type);
2427 /* In C++, sizeof applies to the referent. Handle alignof the same way. */
2428 if (code == REFERENCE_TYPE)
2430 type = TREE_TYPE (type);
2431 code = TREE_CODE (type);
2434 if (code == FUNCTION_TYPE)
2435 t = size_int (FUNCTION_BOUNDARY / BITS_PER_UNIT);
2436 else if (code == VOID_TYPE || code == ERROR_MARK)
2438 else if (!COMPLETE_TYPE_P (type))
2440 error ("__alignof__ applied to an incomplete type");
2444 t = size_int (TYPE_ALIGN (type) / BITS_PER_UNIT);
2446 return fold (build1 (NOP_EXPR, c_size_type_node, t));
2449 /* Implement the __alignof keyword: Return the minimum required
2450 alignment of EXPR, measured in bytes. For VAR_DECL's and
2451 FIELD_DECL's return DECL_ALIGN (which can be set from an
2452 "aligned" __attribute__ specification). */
2455 c_alignof_expr (expr)
2460 if (TREE_CODE (expr) == VAR_DECL)
2461 t = size_int (DECL_ALIGN (expr) / BITS_PER_UNIT);
2463 else if (TREE_CODE (expr) == COMPONENT_REF
2464 && DECL_C_BIT_FIELD (TREE_OPERAND (expr, 1)))
2466 error ("`__alignof' applied to a bit-field");
2469 else if (TREE_CODE (expr) == COMPONENT_REF
2470 && TREE_CODE (TREE_OPERAND (expr, 1)) == FIELD_DECL)
2471 t = size_int (DECL_ALIGN (TREE_OPERAND (expr, 1)) / BITS_PER_UNIT);
2473 else if (TREE_CODE (expr) == INDIRECT_REF)
2475 tree t = TREE_OPERAND (expr, 0);
2477 int bestalign = TYPE_ALIGN (TREE_TYPE (TREE_TYPE (t)));
2479 while (TREE_CODE (t) == NOP_EXPR
2480 && TREE_CODE (TREE_TYPE (TREE_OPERAND (t, 0))) == POINTER_TYPE)
2484 t = TREE_OPERAND (t, 0);
2485 thisalign = TYPE_ALIGN (TREE_TYPE (TREE_TYPE (t)));
2486 if (thisalign > bestalign)
2487 best = t, bestalign = thisalign;
2489 return c_alignof (TREE_TYPE (TREE_TYPE (best)));
2492 return c_alignof (TREE_TYPE (expr));
2494 return fold (build1 (NOP_EXPR, c_size_type_node, t));
2497 /* Give the specifications for the format attributes, used by C and all
2500 static const struct attribute_spec c_format_attribute_table[] =
2502 /* { name, min_len, max_len, decl_req, type_req, fn_type_req, handler } */
2503 { "format", 3, 3, false, true, true,
2504 handle_format_attribute },
2505 { "format_arg", 1, 1, false, true, true,
2506 handle_format_arg_attribute },
2507 { NULL, 0, 0, false, false, false, NULL }
2510 /* Build tree nodes and builtin functions common to both C and C++ language
2514 c_common_nodes_and_builtins ()
2518 #define DEF_PRIMITIVE_TYPE(NAME, VALUE) NAME,
2519 #define DEF_FUNCTION_TYPE_0(NAME, RETURN) NAME,
2520 #define DEF_FUNCTION_TYPE_1(NAME, RETURN, ARG1) NAME,
2521 #define DEF_FUNCTION_TYPE_2(NAME, RETURN, ARG1, ARG2) NAME,
2522 #define DEF_FUNCTION_TYPE_3(NAME, RETURN, ARG1, ARG2, ARG3) NAME,
2523 #define DEF_FUNCTION_TYPE_4(NAME, RETURN, ARG1, ARG2, ARG3, ARG4) NAME,
2524 #define DEF_FUNCTION_TYPE_VAR_0(NAME, RETURN) NAME,
2525 #define DEF_FUNCTION_TYPE_VAR_1(NAME, RETURN, ARG1) NAME,
2526 #define DEF_FUNCTION_TYPE_VAR_2(NAME, RETURN, ARG1, ARG2) NAME,
2527 #define DEF_POINTER_TYPE(NAME, TYPE) NAME,
2528 #include "builtin-types.def"
2529 #undef DEF_PRIMITIVE_TYPE
2530 #undef DEF_FUNCTION_TYPE_0
2531 #undef DEF_FUNCTION_TYPE_1
2532 #undef DEF_FUNCTION_TYPE_2
2533 #undef DEF_FUNCTION_TYPE_3
2534 #undef DEF_FUNCTION_TYPE_4
2535 #undef DEF_FUNCTION_TYPE_VAR_0
2536 #undef DEF_FUNCTION_TYPE_VAR_1
2537 #undef DEF_FUNCTION_TYPE_VAR_2
2538 #undef DEF_POINTER_TYPE
2542 typedef enum builtin_type builtin_type;
2544 tree builtin_types[(int) BT_LAST];
2545 int wchar_type_size;
2546 tree array_domain_type;
2547 tree va_list_ref_type_node;
2548 tree va_list_arg_type_node;
2550 /* We must initialize this before any builtin functions (which might have
2551 attributes) are declared. (c_common_init is too late.) */
2552 format_attribute_table = c_format_attribute_table;
2554 /* Define `int' and `char' first so that dbx will output them first. */
2555 record_builtin_type (RID_INT, NULL, integer_type_node);
2556 record_builtin_type (RID_CHAR, "char", char_type_node);
2558 /* `signed' is the same as `int'. FIXME: the declarations of "signed",
2559 "unsigned long", "long long unsigned" and "unsigned short" were in C++
2560 but not C. Are the conditionals here needed? */
2561 if (c_language == clk_cplusplus)
2562 record_builtin_type (RID_SIGNED, NULL, integer_type_node);
2563 record_builtin_type (RID_LONG, "long int", long_integer_type_node);
2564 record_builtin_type (RID_UNSIGNED, "unsigned int", unsigned_type_node);
2565 record_builtin_type (RID_MAX, "long unsigned int",
2566 long_unsigned_type_node);
2567 if (c_language == clk_cplusplus)
2568 record_builtin_type (RID_MAX, "unsigned long", long_unsigned_type_node);
2569 record_builtin_type (RID_MAX, "long long int",
2570 long_long_integer_type_node);
2571 record_builtin_type (RID_MAX, "long long unsigned int",
2572 long_long_unsigned_type_node);
2573 if (c_language == clk_cplusplus)
2574 record_builtin_type (RID_MAX, "long long unsigned",
2575 long_long_unsigned_type_node);
2576 record_builtin_type (RID_SHORT, "short int", short_integer_type_node);
2577 record_builtin_type (RID_MAX, "short unsigned int",
2578 short_unsigned_type_node);
2579 if (c_language == clk_cplusplus)
2580 record_builtin_type (RID_MAX, "unsigned short",
2581 short_unsigned_type_node);
2583 /* Define both `signed char' and `unsigned char'. */
2584 record_builtin_type (RID_MAX, "signed char", signed_char_type_node);
2585 record_builtin_type (RID_MAX, "unsigned char", unsigned_char_type_node);
2587 /* These are types that c_common_type_for_size and
2588 c_common_type_for_mode use. */
2589 (*lang_hooks.decls.pushdecl) (build_decl (TYPE_DECL, NULL_TREE,
2591 (*lang_hooks.decls.pushdecl) (build_decl (TYPE_DECL, NULL_TREE,
2593 (*lang_hooks.decls.pushdecl) (build_decl (TYPE_DECL, NULL_TREE,
2595 (*lang_hooks.decls.pushdecl) (build_decl (TYPE_DECL, NULL_TREE,
2597 #if HOST_BITS_PER_WIDE_INT >= 64
2598 (*lang_hooks.decls.pushdecl) (build_decl (TYPE_DECL,
2599 get_identifier ("__int128_t"),
2602 (*lang_hooks.decls.pushdecl) (build_decl (TYPE_DECL, NULL_TREE,
2603 unsigned_intQI_type_node));
2604 (*lang_hooks.decls.pushdecl) (build_decl (TYPE_DECL, NULL_TREE,
2605 unsigned_intHI_type_node));
2606 (*lang_hooks.decls.pushdecl) (build_decl (TYPE_DECL, NULL_TREE,
2607 unsigned_intSI_type_node));
2608 (*lang_hooks.decls.pushdecl) (build_decl (TYPE_DECL, NULL_TREE,
2609 unsigned_intDI_type_node));
2610 #if HOST_BITS_PER_WIDE_INT >= 64
2611 (*lang_hooks.decls.pushdecl) (build_decl (TYPE_DECL,
2612 get_identifier ("__uint128_t"),
2613 unsigned_intTI_type_node));
2616 /* Create the widest literal types. */
2617 widest_integer_literal_type_node
2618 = make_signed_type (HOST_BITS_PER_WIDE_INT * 2);
2619 (*lang_hooks.decls.pushdecl) (build_decl (TYPE_DECL, NULL_TREE,
2620 widest_integer_literal_type_node));
2622 widest_unsigned_literal_type_node
2623 = make_unsigned_type (HOST_BITS_PER_WIDE_INT * 2);
2624 (*lang_hooks.decls.pushdecl) (build_decl (TYPE_DECL, NULL_TREE,
2625 widest_unsigned_literal_type_node));
2627 /* `unsigned long' is the standard type for sizeof.
2628 Note that stddef.h uses `unsigned long',
2629 and this must agree, even if long and int are the same size. */
2631 TREE_TYPE (identifier_global_value (get_identifier (SIZE_TYPE)));
2632 signed_size_type_node = c_common_signed_type (c_size_type_node);
2633 set_sizetype (c_size_type_node);
2635 build_common_tree_nodes_2 (flag_short_double);
2637 record_builtin_type (RID_FLOAT, NULL, float_type_node);
2638 record_builtin_type (RID_DOUBLE, NULL, double_type_node);
2639 record_builtin_type (RID_MAX, "long double", long_double_type_node);
2641 (*lang_hooks.decls.pushdecl) (build_decl (TYPE_DECL,
2642 get_identifier ("complex int"),
2643 complex_integer_type_node));
2644 (*lang_hooks.decls.pushdecl) (build_decl (TYPE_DECL,
2645 get_identifier ("complex float"),
2646 complex_float_type_node));
2647 (*lang_hooks.decls.pushdecl) (build_decl (TYPE_DECL,
2648 get_identifier ("complex double"),
2649 complex_double_type_node));
2650 (*lang_hooks.decls.pushdecl)
2651 (build_decl (TYPE_DECL, get_identifier ("complex long double"),
2652 complex_long_double_type_node));
2654 record_builtin_type (RID_VOID, NULL, void_type_node);
2656 void_zero_node = build_int_2 (0, 0);
2657 TREE_TYPE (void_zero_node) = void_type_node;
2659 void_list_node = build_void_list_node ();
2661 /* Make a type to be the domain of a few array types
2662 whose domains don't really matter.
2663 200 is small enough that it always fits in size_t
2664 and large enough that it can hold most function names for the
2665 initializations of __FUNCTION__ and __PRETTY_FUNCTION__. */
2666 array_domain_type = build_index_type (size_int (200));
2668 /* Make a type for arrays of characters.
2669 With luck nothing will ever really depend on the length of this
2671 char_array_type_node
2672 = build_array_type (char_type_node, array_domain_type);
2674 /* Likewise for arrays of ints. */
2676 = build_array_type (integer_type_node, array_domain_type);
2678 string_type_node = build_pointer_type (char_type_node);
2679 const_string_type_node
2680 = build_pointer_type (build_qualified_type
2681 (char_type_node, TYPE_QUAL_CONST));
2683 (*targetm.init_builtins) ();
2685 /* This is special for C++ so functions can be overloaded. */
2686 wchar_type_node = get_identifier (flag_short_wchar
2687 ? "short unsigned int"
2689 wchar_type_node = TREE_TYPE (identifier_global_value (wchar_type_node));
2690 wchar_type_size = TYPE_PRECISION (wchar_type_node);
2691 if (c_language == clk_cplusplus)
2693 if (TREE_UNSIGNED (wchar_type_node))
2694 wchar_type_node = make_unsigned_type (wchar_type_size);
2696 wchar_type_node = make_signed_type (wchar_type_size);
2697 record_builtin_type (RID_WCHAR, "wchar_t", wchar_type_node);
2701 signed_wchar_type_node = c_common_signed_type (wchar_type_node);
2702 unsigned_wchar_type_node = c_common_unsigned_type (wchar_type_node);
2705 /* This is for wide string constants. */
2706 wchar_array_type_node
2707 = build_array_type (wchar_type_node, array_domain_type);
2710 TREE_TYPE (identifier_global_value (get_identifier (WINT_TYPE)));
2713 TREE_TYPE (identifier_global_value (get_identifier (INTMAX_TYPE)));
2715 TREE_TYPE (identifier_global_value (get_identifier (UINTMAX_TYPE)));
2717 default_function_type = build_function_type (integer_type_node, NULL_TREE);
2719 = TREE_TYPE (identifier_global_value (get_identifier (PTRDIFF_TYPE)));
2720 unsigned_ptrdiff_type_node = c_common_unsigned_type (ptrdiff_type_node);
2722 (*lang_hooks.decls.pushdecl)
2723 (build_decl (TYPE_DECL, get_identifier ("__builtin_va_list"),
2724 va_list_type_node));
2726 (*lang_hooks.decls.pushdecl)
2727 (build_decl (TYPE_DECL, get_identifier ("__builtin_ptrdiff_t"),
2728 ptrdiff_type_node));
2730 (*lang_hooks.decls.pushdecl)
2731 (build_decl (TYPE_DECL, get_identifier ("__builtin_size_t"),
2734 if (TREE_CODE (va_list_type_node) == ARRAY_TYPE)
2736 va_list_arg_type_node = va_list_ref_type_node =
2737 build_pointer_type (TREE_TYPE (va_list_type_node));
2741 va_list_arg_type_node = va_list_type_node;
2742 va_list_ref_type_node = build_reference_type (va_list_type_node);
2745 #define DEF_PRIMITIVE_TYPE(ENUM, VALUE) \
2746 builtin_types[(int) ENUM] = VALUE;
2747 #define DEF_FUNCTION_TYPE_0(ENUM, RETURN) \
2748 builtin_types[(int) ENUM] \
2749 = build_function_type (builtin_types[(int) RETURN], \
2751 #define DEF_FUNCTION_TYPE_1(ENUM, RETURN, ARG1) \
2752 builtin_types[(int) ENUM] \
2753 = build_function_type (builtin_types[(int) RETURN], \
2754 tree_cons (NULL_TREE, \
2755 builtin_types[(int) ARG1], \
2757 #define DEF_FUNCTION_TYPE_2(ENUM, RETURN, ARG1, ARG2) \
2758 builtin_types[(int) ENUM] \
2759 = build_function_type \
2760 (builtin_types[(int) RETURN], \
2761 tree_cons (NULL_TREE, \
2762 builtin_types[(int) ARG1], \
2763 tree_cons (NULL_TREE, \
2764 builtin_types[(int) ARG2], \
2766 #define DEF_FUNCTION_TYPE_3(ENUM, RETURN, ARG1, ARG2, ARG3) \
2767 builtin_types[(int) ENUM] \
2768 = build_function_type \
2769 (builtin_types[(int) RETURN], \
2770 tree_cons (NULL_TREE, \
2771 builtin_types[(int) ARG1], \
2772 tree_cons (NULL_TREE, \
2773 builtin_types[(int) ARG2], \
2774 tree_cons (NULL_TREE, \
2775 builtin_types[(int) ARG3], \
2777 #define DEF_FUNCTION_TYPE_4(ENUM, RETURN, ARG1, ARG2, ARG3, ARG4) \
2778 builtin_types[(int) ENUM] \
2779 = build_function_type \
2780 (builtin_types[(int) RETURN], \
2781 tree_cons (NULL_TREE, \
2782 builtin_types[(int) ARG1], \
2783 tree_cons (NULL_TREE, \
2784 builtin_types[(int) ARG2], \
2787 builtin_types[(int) ARG3], \
2788 tree_cons (NULL_TREE, \
2789 builtin_types[(int) ARG4], \
2790 void_list_node)))));
2791 #define DEF_FUNCTION_TYPE_VAR_0(ENUM, RETURN) \
2792 builtin_types[(int) ENUM] \
2793 = build_function_type (builtin_types[(int) RETURN], NULL_TREE);
2794 #define DEF_FUNCTION_TYPE_VAR_1(ENUM, RETURN, ARG1) \
2795 builtin_types[(int) ENUM] \
2796 = build_function_type (builtin_types[(int) RETURN], \
2797 tree_cons (NULL_TREE, \
2798 builtin_types[(int) ARG1], \
2801 #define DEF_FUNCTION_TYPE_VAR_2(ENUM, RETURN, ARG1, ARG2) \
2802 builtin_types[(int) ENUM] \
2803 = build_function_type \
2804 (builtin_types[(int) RETURN], \
2805 tree_cons (NULL_TREE, \
2806 builtin_types[(int) ARG1], \
2807 tree_cons (NULL_TREE, \
2808 builtin_types[(int) ARG2], \
2810 #define DEF_POINTER_TYPE(ENUM, TYPE) \
2811 builtin_types[(int) ENUM] \
2812 = build_pointer_type (builtin_types[(int) TYPE]);
2813 #include "builtin-types.def"
2814 #undef DEF_PRIMITIVE_TYPE
2815 #undef DEF_FUNCTION_TYPE_1
2816 #undef DEF_FUNCTION_TYPE_2
2817 #undef DEF_FUNCTION_TYPE_3
2818 #undef DEF_FUNCTION_TYPE_4
2819 #undef DEF_FUNCTION_TYPE_VAR_0
2820 #undef DEF_FUNCTION_TYPE_VAR_1
2821 #undef DEF_POINTER_TYPE
2823 #define DEF_BUILTIN(ENUM, NAME, CLASS, \
2824 TYPE, LIBTYPE, BOTH_P, FALLBACK_P, NONANSI_P) \
2829 if (strncmp (NAME, "__builtin_", strlen ("__builtin_")) != 0) \
2833 decl = builtin_function (NAME, builtin_types[TYPE], ENUM, \
2836 ? (NAME + strlen ("__builtin_")) \
2839 decl = builtin_function_2 (NAME, \
2840 NAME + strlen ("__builtin_"), \
2841 builtin_types[TYPE], \
2842 builtin_types[LIBTYPE], \
2847 /*noreturn_p=*/0); \
2849 built_in_decls[(int) ENUM] = decl; \
2851 #include "builtins.def"
2854 /* Declare _exit and _Exit just to mark them as non-returning. */
2855 builtin_function_2 (NULL, "_exit", NULL_TREE,
2856 builtin_types[BT_FN_VOID_INT],
2857 0, NOT_BUILT_IN, 0, 1, 1);
2858 builtin_function_2 (NULL, "_Exit", NULL_TREE,
2859 builtin_types[BT_FN_VOID_INT],
2860 0, NOT_BUILT_IN, 0, !flag_isoc99, 1);
2862 /* Declare these functions non-returning
2863 to avoid spurious "control drops through" warnings. */
2864 builtin_function_2 (NULL, "abort",
2865 NULL_TREE, ((c_language == clk_cplusplus)
2866 ? builtin_types[BT_FN_VOID]
2867 : builtin_types[BT_FN_VOID_VAR]),
2868 0, NOT_BUILT_IN, 0, 0, 1);
2870 builtin_function_2 (NULL, "exit",
2871 NULL_TREE, ((c_language == clk_cplusplus)
2872 ? builtin_types[BT_FN_VOID_INT]
2873 : builtin_types[BT_FN_VOID_VAR]),
2874 0, NOT_BUILT_IN, 0, 0, 1);
2876 main_identifier_node = get_identifier ("main");
2878 /* ??? Perhaps there's a better place to do this. But it is related
2879 to __builtin_va_arg, so it isn't that off-the-wall. */
2880 lang_type_promotes_to = simple_type_promotes_to;
2884 build_va_arg (expr, type)
2887 return build1 (VA_ARG_EXPR, type, expr);
2891 /* Linked list of disabled built-in functions. */
2893 typedef struct disabled_builtin
2896 struct disabled_builtin *next;
2898 static disabled_builtin *disabled_builtins = NULL;
2900 static bool builtin_function_disabled_p PARAMS ((const char *));
2902 /* Disable a built-in function specified by -fno-builtin-NAME. If NAME
2903 begins with "__builtin_", give an error. */
2906 disable_builtin_function (name)
2909 if (strncmp (name, "__builtin_", strlen ("__builtin_")) == 0)
2910 error ("cannot disable built-in function `%s'", name);
2913 disabled_builtin *new = xmalloc (sizeof (disabled_builtin));
2915 new->next = disabled_builtins;
2916 disabled_builtins = new;
2921 /* Return true if the built-in function NAME has been disabled, false
2925 builtin_function_disabled_p (name)
2928 disabled_builtin *p;
2929 for (p = disabled_builtins; p != NULL; p = p->next)
2931 if (strcmp (name, p->name) == 0)
2938 /* Possibly define a builtin function with one or two names. BUILTIN_NAME
2939 is an __builtin_-prefixed name; NAME is the ordinary name; one or both
2940 of these may be NULL (though both being NULL is useless).
2941 BUILTIN_TYPE is the type of the __builtin_-prefixed function;
2942 TYPE is the type of the function with the ordinary name. These
2943 may differ if the ordinary name is declared with a looser type to avoid
2944 conflicts with headers. FUNCTION_CODE and CLASS are as for
2945 builtin_function. If LIBRARY_NAME_P is nonzero, NAME is passed as
2946 the LIBRARY_NAME parameter to builtin_function when declaring BUILTIN_NAME.
2947 If NONANSI_P is nonzero, the name NAME is treated as a non-ANSI name; if
2948 NORETURN_P is nonzero, the function is marked as non-returning.
2949 Returns the declaration of BUILTIN_NAME, if any, otherwise
2950 the declaration of NAME. Does not declare NAME if flag_no_builtin,
2951 or if NONANSI_P and flag_no_nonansi_builtin. */
2954 builtin_function_2 (builtin_name, name, builtin_type, type, function_code,
2955 class, library_name_p, nonansi_p, noreturn_p)
2956 const char *builtin_name;
2961 enum built_in_class class;
2966 tree bdecl = NULL_TREE;
2967 tree decl = NULL_TREE;
2968 if (builtin_name != 0)
2970 bdecl = builtin_function (builtin_name, builtin_type, function_code,
2971 class, library_name_p ? name : NULL);
2974 TREE_THIS_VOLATILE (bdecl) = 1;
2975 TREE_SIDE_EFFECTS (bdecl) = 1;
2978 if (name != 0 && !flag_no_builtin && !builtin_function_disabled_p (name)
2979 && !(nonansi_p && flag_no_nonansi_builtin))
2981 decl = builtin_function (name, type, function_code, class, NULL);
2983 DECL_BUILT_IN_NONANSI (decl) = 1;
2986 TREE_THIS_VOLATILE (decl) = 1;
2987 TREE_SIDE_EFFECTS (decl) = 1;
2990 return (bdecl != 0 ? bdecl : decl);
2993 /* Nonzero if the type T promotes to int. This is (nearly) the
2994 integral promotions defined in ISO C99 6.3.1.1/2. */
2997 c_promoting_integer_type_p (t)
3000 switch (TREE_CODE (t))
3003 return (TYPE_MAIN_VARIANT (t) == char_type_node
3004 || TYPE_MAIN_VARIANT (t) == signed_char_type_node
3005 || TYPE_MAIN_VARIANT (t) == unsigned_char_type_node
3006 || TYPE_MAIN_VARIANT (t) == short_integer_type_node
3007 || TYPE_MAIN_VARIANT (t) == short_unsigned_type_node
3008 || TYPE_PRECISION (t) < TYPE_PRECISION (integer_type_node));
3011 /* ??? Technically all enumerations not larger than an int
3012 promote to an int. But this is used along code paths
3013 that only want to notice a size change. */
3014 return TYPE_PRECISION (t) < TYPE_PRECISION (integer_type_node);
3024 /* Given a type, apply default promotions wrt unnamed function arguments
3025 and return the new type. Return NULL_TREE if no change. */
3026 /* ??? There is a function of the same name in the C++ front end that
3027 does something similar, but is more thorough and does not return NULL
3028 if no change. We could perhaps share code, but it would make the
3029 self_promoting_type property harder to identify. */
3032 simple_type_promotes_to (type)
3035 if (TYPE_MAIN_VARIANT (type) == float_type_node)
3036 return double_type_node;
3038 if (c_promoting_integer_type_p (type))
3040 /* Preserve unsignedness if not really getting any wider. */
3041 if (TREE_UNSIGNED (type)
3042 && (TYPE_PRECISION (type) == TYPE_PRECISION (integer_type_node)))
3043 return unsigned_type_node;
3044 return integer_type_node;
3050 /* Return 1 if PARMS specifies a fixed number of parameters
3051 and none of their types is affected by default promotions. */
3054 self_promoting_args_p (parms)
3058 for (t = parms; t; t = TREE_CHAIN (t))
3060 tree type = TREE_VALUE (t);
3062 if (TREE_CHAIN (t) == 0 && type != void_type_node)
3068 if (TYPE_MAIN_VARIANT (type) == float_type_node)
3071 if (c_promoting_integer_type_p (type))
3077 /* Recursively examines the array elements of TYPE, until a non-array
3078 element type is found. */
3081 strip_array_types (type)
3084 while (TREE_CODE (type) == ARRAY_TYPE)
3085 type = TREE_TYPE (type);
3090 static tree expand_unordered_cmp PARAMS ((tree, tree, enum tree_code,
3093 /* Expand a call to an unordered comparison function such as
3094 __builtin_isgreater(). FUNCTION is the function's declaration and
3095 PARAMS a list of the values passed. For __builtin_isunordered(),
3096 UNORDERED_CODE is UNORDERED_EXPR and ORDERED_CODE is NOP_EXPR. In
3097 other cases, UNORDERED_CODE and ORDERED_CODE are comparison codes
3098 that give the opposite of the desired result. UNORDERED_CODE is
3099 used for modes that can hold NaNs and ORDERED_CODE is used for the
3103 expand_unordered_cmp (function, params, unordered_code, ordered_code)
3104 tree function, params;
3105 enum tree_code unordered_code, ordered_code;
3107 tree arg0, arg1, type;
3108 enum tree_code code0, code1;
3110 /* Check that we have exactly two arguments. */
3111 if (params == 0 || TREE_CHAIN (params) == 0)
3113 error ("too few arguments to function `%s'",
3114 IDENTIFIER_POINTER (DECL_NAME (function)));
3115 return error_mark_node;
3117 else if (TREE_CHAIN (TREE_CHAIN (params)) != 0)
3119 error ("too many arguments to function `%s'",
3120 IDENTIFIER_POINTER (DECL_NAME (function)));
3121 return error_mark_node;
3124 arg0 = TREE_VALUE (params);
3125 arg1 = TREE_VALUE (TREE_CHAIN (params));
3127 code0 = TREE_CODE (TREE_TYPE (arg0));
3128 code1 = TREE_CODE (TREE_TYPE (arg1));
3130 /* Make sure that the arguments have a common type of REAL. */
3132 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE)
3133 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE))
3134 type = common_type (TREE_TYPE (arg0), TREE_TYPE (arg1));
3136 if (type == 0 || TREE_CODE (type) != REAL_TYPE)
3138 error ("non-floating-point argument to function `%s'",
3139 IDENTIFIER_POINTER (DECL_NAME (function)));
3140 return error_mark_node;
3143 if (unordered_code == UNORDERED_EXPR)
3145 if (MODE_HAS_NANS (TYPE_MODE (type)))
3146 return build_binary_op (unordered_code,
3147 convert (type, arg0),
3148 convert (type, arg1),
3151 return integer_zero_node;
3154 return build_unary_op (TRUTH_NOT_EXPR,
3155 build_binary_op (MODE_HAS_NANS (TYPE_MODE (type))
3158 convert (type, arg0),
3159 convert (type, arg1),
3165 /* Recognize certain built-in functions so we can make tree-codes
3166 other than CALL_EXPR. We do this when it enables fold-const.c
3167 to do something useful. */
3168 /* ??? By rights this should go in builtins.c, but only C and C++
3169 implement build_{binary,unary}_op. Not exactly sure what bits
3170 of functionality are actually needed from those functions, or
3171 where the similar functionality exists in the other front ends. */
3174 expand_tree_builtin (function, params, coerced_params)
3175 tree function, params, coerced_params;
3177 if (DECL_BUILT_IN_CLASS (function) != BUILT_IN_NORMAL)
3180 switch (DECL_FUNCTION_CODE (function))
3184 case BUILT_IN_LLABS:
3185 case BUILT_IN_IMAXABS:
3187 case BUILT_IN_FABSL:
3188 case BUILT_IN_FABSF:
3189 if (coerced_params == 0)
3190 return integer_zero_node;
3191 return build_unary_op (ABS_EXPR, TREE_VALUE (coerced_params), 0);
3194 case BUILT_IN_CONJF:
3195 case BUILT_IN_CONJL:
3196 if (coerced_params == 0)
3197 return integer_zero_node;
3198 return build_unary_op (CONJ_EXPR, TREE_VALUE (coerced_params), 0);
3200 case BUILT_IN_CREAL:
3201 case BUILT_IN_CREALF:
3202 case BUILT_IN_CREALL:
3203 if (coerced_params == 0)
3204 return integer_zero_node;
3205 return build_unary_op (REALPART_EXPR, TREE_VALUE (coerced_params), 0);
3207 case BUILT_IN_CIMAG:
3208 case BUILT_IN_CIMAGF:
3209 case BUILT_IN_CIMAGL:
3210 if (coerced_params == 0)
3211 return integer_zero_node;
3212 return build_unary_op (IMAGPART_EXPR, TREE_VALUE (coerced_params), 0);
3214 case BUILT_IN_ISGREATER:
3215 return expand_unordered_cmp (function, params, UNLE_EXPR, LE_EXPR);
3217 case BUILT_IN_ISGREATEREQUAL:
3218 return expand_unordered_cmp (function, params, UNLT_EXPR, LT_EXPR);
3220 case BUILT_IN_ISLESS:
3221 return expand_unordered_cmp (function, params, UNGE_EXPR, GE_EXPR);
3223 case BUILT_IN_ISLESSEQUAL:
3224 return expand_unordered_cmp (function, params, UNGT_EXPR, GT_EXPR);
3226 case BUILT_IN_ISLESSGREATER:
3227 return expand_unordered_cmp (function, params, UNEQ_EXPR, EQ_EXPR);
3229 case BUILT_IN_ISUNORDERED:
3230 return expand_unordered_cmp (function, params, UNORDERED_EXPR, NOP_EXPR);
3239 /* Returns non-zero if CODE is the code for a statement. */
3242 statement_code_p (code)
3243 enum tree_code code;
3268 if (lang_statement_code_p)
3269 return (*lang_statement_code_p) (code);
3274 /* Walk the statement tree, rooted at *tp. Apply FUNC to all the
3275 sub-trees of *TP in a pre-order traversal. FUNC is called with the
3276 DATA and the address of each sub-tree. If FUNC returns a non-NULL
3277 value, the traversal is aborted, and the value returned by FUNC is
3278 returned. If FUNC sets WALK_SUBTREES to zero, then the subtrees of
3279 the node being visited are not walked.
3281 We don't need a without_duplicates variant of this one because the
3282 statement tree is a tree, not a graph. */
3285 walk_stmt_tree (tp, func, data)
3290 enum tree_code code;
3295 #define WALK_SUBTREE(NODE) \
3298 result = walk_stmt_tree (&(NODE), func, data); \
3304 /* Skip empty subtrees. */
3308 /* Skip subtrees below non-statement nodes. */
3309 if (!statement_code_p (TREE_CODE (*tp)))
3312 /* Call the function. */
3314 result = (*func) (tp, &walk_subtrees, data);
3316 /* If we found something, return it. */
3320 /* FUNC may have modified the tree, recheck that we're looking at a
3322 code = TREE_CODE (*tp);
3323 if (!statement_code_p (code))
3326 /* Visit the subtrees unless FUNC decided that there was nothing
3327 interesting below this point in the tree. */
3330 /* Walk over all the sub-trees of this operand. Statement nodes
3331 never contain RTL, and we needn't worry about TARGET_EXPRs. */
3332 len = TREE_CODE_LENGTH (code);
3334 /* Go through the subtrees. We need to do this in forward order so
3335 that the scope of a FOR_EXPR is handled properly. */
3336 for (i = 0; i < len; ++i)
3337 WALK_SUBTREE (TREE_OPERAND (*tp, i));
3340 /* Finally visit the chain. This can be tail-recursion optimized if
3341 we write it this way. */
3342 return walk_stmt_tree (&TREE_CHAIN (*tp), func, data);
3347 /* Used to compare case labels. K1 and K2 are actually tree nodes
3348 representing case labels, or NULL_TREE for a `default' label.
3349 Returns -1 if K1 is ordered before K2, -1 if K1 is ordered after
3350 K2, and 0 if K1 and K2 are equal. */
3353 case_compare (k1, k2)
3357 /* Consider a NULL key (such as arises with a `default' label) to be
3358 smaller than anything else. */
3364 return tree_int_cst_compare ((tree) k1, (tree) k2);
3367 /* Process a case label for the range LOW_VALUE ... HIGH_VALUE. If
3368 LOW_VALUE and HIGH_VALUE are both NULL_TREE then this case label is
3369 actually a `default' label. If only HIGH_VALUE is NULL_TREE, then
3370 case label was declared using the usual C/C++ syntax, rather than
3371 the GNU case range extension. CASES is a tree containing all the
3372 case ranges processed so far; COND is the condition for the
3373 switch-statement itself. Returns the CASE_LABEL created, or
3374 ERROR_MARK_NODE if no CASE_LABEL is created. */
3377 c_add_case_label (cases, cond, low_value, high_value)
3386 splay_tree_node node;
3388 /* Create the LABEL_DECL itself. */
3389 label = build_decl (LABEL_DECL, NULL_TREE, NULL_TREE);
3390 DECL_CONTEXT (label) = current_function_decl;
3392 /* If there was an error processing the switch condition, bail now
3393 before we get more confused. */
3394 if (!cond || cond == error_mark_node)
3396 /* Add a label anyhow so that the back-end doesn't think that
3397 the beginning of the switch is unreachable. */
3399 add_stmt (build_case_label (NULL_TREE, NULL_TREE, label));
3400 return error_mark_node;
3403 if ((low_value && TREE_TYPE (low_value)
3404 && POINTER_TYPE_P (TREE_TYPE (low_value)))
3405 || (high_value && TREE_TYPE (high_value)
3406 && POINTER_TYPE_P (TREE_TYPE (high_value))))
3407 error ("pointers are not permitted as case values");
3409 /* Case ranges are a GNU extension. */
3410 if (high_value && pedantic)
3412 if (c_language == clk_cplusplus)
3413 pedwarn ("ISO C++ forbids range expressions in switch statements");
3415 pedwarn ("ISO C forbids range expressions in switch statements");
3418 type = TREE_TYPE (cond);
3421 low_value = check_case_value (low_value);
3422 low_value = convert_and_check (type, low_value);
3426 high_value = check_case_value (high_value);
3427 high_value = convert_and_check (type, high_value);
3430 /* If an error has occurred, bail out now. */
3431 if (low_value == error_mark_node || high_value == error_mark_node)
3434 add_stmt (build_case_label (NULL_TREE, NULL_TREE, label));
3435 return error_mark_node;
3438 /* If the LOW_VALUE and HIGH_VALUE are the same, then this isn't
3439 really a case range, even though it was written that way. Remove
3440 the HIGH_VALUE to simplify later processing. */
3441 if (tree_int_cst_equal (low_value, high_value))
3442 high_value = NULL_TREE;
3443 if (low_value && high_value
3444 && !tree_int_cst_lt (low_value, high_value))
3445 warning ("empty range specified");
3447 /* Look up the LOW_VALUE in the table of case labels we already
3449 node = splay_tree_lookup (cases, (splay_tree_key) low_value);
3450 /* If there was not an exact match, check for overlapping ranges.
3451 There's no need to do this if there's no LOW_VALUE or HIGH_VALUE;
3452 that's a `default' label and the only overlap is an exact match. */
3453 if (!node && (low_value || high_value))
3455 splay_tree_node low_bound;
3456 splay_tree_node high_bound;
3458 /* Even though there wasn't an exact match, there might be an
3459 overlap between this case range and another case range.
3460 Since we've (inductively) not allowed any overlapping case
3461 ranges, we simply need to find the greatest low case label
3462 that is smaller that LOW_VALUE, and the smallest low case
3463 label that is greater than LOW_VALUE. If there is an overlap
3464 it will occur in one of these two ranges. */
3465 low_bound = splay_tree_predecessor (cases,
3466 (splay_tree_key) low_value);
3467 high_bound = splay_tree_successor (cases,
3468 (splay_tree_key) low_value);
3470 /* Check to see if the LOW_BOUND overlaps. It is smaller than
3471 the LOW_VALUE, so there is no need to check unless the
3472 LOW_BOUND is in fact itself a case range. */
3474 && CASE_HIGH ((tree) low_bound->value)
3475 && tree_int_cst_compare (CASE_HIGH ((tree) low_bound->value),
3478 /* Check to see if the HIGH_BOUND overlaps. The low end of that
3479 range is bigger than the low end of the current range, so we
3480 are only interested if the current range is a real range, and
3481 not an ordinary case label. */
3484 && (tree_int_cst_compare ((tree) high_bound->key,
3489 /* If there was an overlap, issue an error. */
3492 tree duplicate = CASE_LABEL_DECL ((tree) node->value);
3496 error ("duplicate (or overlapping) case value");
3497 error_with_decl (duplicate,
3498 "this is the first entry overlapping that value");
3502 error ("duplicate case value") ;
3503 error_with_decl (duplicate, "previously used here");
3507 error ("multiple default labels in one switch");
3508 error_with_decl (duplicate, "this is the first default label");
3511 add_stmt (build_case_label (NULL_TREE, NULL_TREE, label));
3514 /* Add a CASE_LABEL to the statement-tree. */
3515 case_label = add_stmt (build_case_label (low_value, high_value, label));
3516 /* Register this case label in the splay tree. */
3517 splay_tree_insert (cases,
3518 (splay_tree_key) low_value,
3519 (splay_tree_value) case_label);
3524 /* Finish an expression taking the address of LABEL. Returns an
3525 expression for the address. */
3528 finish_label_address_expr (label)
3535 if (c_language == clk_cplusplus)
3536 pedwarn ("ISO C++ forbids taking the address of a label");
3538 pedwarn ("ISO C forbids taking the address of a label");
3541 label = lookup_label (label);
3542 if (label == NULL_TREE)
3543 result = null_pointer_node;
3546 TREE_USED (label) = 1;
3547 result = build1 (ADDR_EXPR, ptr_type_node, label);
3548 TREE_CONSTANT (result) = 1;
3549 /* The current function in not necessarily uninlinable.
3550 Computed gotos are incompatible with inlining, but the value
3551 here could be used only in a diagnostic, for example. */
3557 /* Mark P (a stmt_tree) for GC. The use of a `void *' for the
3558 parameter allows this function to be used as a GC-marking
3565 stmt_tree st = (stmt_tree) p;
3567 ggc_mark_tree (st->x_last_stmt);
3568 ggc_mark_tree (st->x_last_expr_type);
3571 /* Mark LD for GC. */
3574 c_mark_lang_decl (c)
3575 struct c_lang_decl *c ATTRIBUTE_UNUSED;
3579 /* Mark F for GC. */
3582 mark_c_language_function (f)
3583 struct language_function *f;
3588 mark_stmt_tree (&f->x_stmt_tree);
3589 ggc_mark_tree (f->x_scope_stmt_stack);
3592 /* Hook used by expand_expr to expand language-specific tree codes. */
3595 c_expand_expr (exp, target, tmode, modifier)
3598 enum machine_mode tmode;
3599 int modifier; /* Actually enum_modifier. */
3601 switch (TREE_CODE (exp))
3607 bool preserve_result = false;
3609 /* Since expand_expr_stmt calls free_temp_slots after every
3610 expression statement, we must call push_temp_slots here.
3611 Otherwise, any temporaries in use now would be considered
3612 out-of-scope after the first EXPR_STMT from within the
3615 rtl_expr = expand_start_stmt_expr ();
3617 /* If we want the result of this expression, find the last
3618 EXPR_STMT in the COMPOUND_STMT and mark it as addressable. */
3619 if (target != const0_rtx
3620 && TREE_CODE (STMT_EXPR_STMT (exp)) == COMPOUND_STMT
3621 && TREE_CODE (COMPOUND_BODY (STMT_EXPR_STMT (exp))) == SCOPE_STMT)
3623 tree expr = COMPOUND_BODY (STMT_EXPR_STMT (exp));
3624 tree last = TREE_CHAIN (expr);
3626 while (TREE_CHAIN (last))
3629 last = TREE_CHAIN (last);
3632 if (TREE_CODE (last) == SCOPE_STMT
3633 && TREE_CODE (expr) == EXPR_STMT)
3635 TREE_ADDRESSABLE (expr) = 1;
3636 preserve_result = true;
3640 expand_stmt (STMT_EXPR_STMT (exp));
3641 expand_end_stmt_expr (rtl_expr);
3643 result = expand_expr (rtl_expr, target, tmode, modifier);
3644 if (preserve_result && GET_CODE (result) == MEM)
3646 if (GET_MODE (result) != BLKmode)
3647 result = copy_to_reg (result);
3649 preserve_temp_slots (result);
3659 if (TREE_CODE (TREE_OPERAND (exp, 0)) == ADDR_EXPR
3660 && (TREE_CODE (TREE_OPERAND (TREE_OPERAND (exp, 0), 0))
3662 && DECL_BUILT_IN (TREE_OPERAND (TREE_OPERAND (exp, 0), 0))
3663 && (DECL_BUILT_IN_CLASS (TREE_OPERAND (TREE_OPERAND (exp, 0), 0))
3664 == BUILT_IN_FRONTEND))
3665 return c_expand_builtin (exp, target, tmode, modifier);
3671 case COMPOUND_LITERAL_EXPR:
3673 /* Initialize the anonymous variable declared in the compound
3674 literal, then return the variable. */
3675 tree decl = COMPOUND_LITERAL_EXPR_DECL (exp);
3676 emit_local_var (decl);
3677 return expand_expr (decl, target, tmode, modifier);
3688 /* Hook used by safe_from_p to handle language-specific tree codes. */
3691 c_safe_from_p (target, exp)
3695 /* We can see statements here when processing the body of a
3696 statement-expression. For a declaration statement declaring a
3697 variable, look at the variable's initializer. */
3698 if (TREE_CODE (exp) == DECL_STMT)
3700 tree decl = DECL_STMT_DECL (exp);
3702 if (TREE_CODE (decl) == VAR_DECL
3703 && DECL_INITIAL (decl)
3704 && !safe_from_p (target, DECL_INITIAL (decl), /*top_p=*/0))
3708 /* For any statement, we must follow the statement-chain. */
3709 if (statement_code_p (TREE_CODE (exp)) && TREE_CHAIN (exp))
3710 return safe_from_p (target, TREE_CHAIN (exp), /*top_p=*/0);
3712 /* Assume everything else is safe. */
3716 /* Hook used by unsafe_for_reeval to handle language-specific tree codes. */
3719 c_common_unsafe_for_reeval (exp)
3722 /* Statement expressions may not be reevaluated, likewise compound
3724 if (TREE_CODE (exp) == STMT_EXPR
3725 || TREE_CODE (exp) == COMPOUND_LITERAL_EXPR)
3728 /* Walk all other expressions. */
3732 /* Hook used by staticp to handle language-specific tree codes. */
3738 if (TREE_CODE (exp) == COMPOUND_LITERAL_EXPR
3739 && TREE_STATIC (COMPOUND_LITERAL_EXPR_DECL (exp)))
3744 #define CALLED_AS_BUILT_IN(NODE) \
3745 (!strncmp (IDENTIFIER_POINTER (DECL_NAME (NODE)), "__builtin_", 10))
3748 c_expand_builtin (exp, target, tmode, modifier)
3751 enum machine_mode tmode;
3752 enum expand_modifier modifier;
3754 tree type = TREE_TYPE (exp);
3755 tree fndecl = TREE_OPERAND (TREE_OPERAND (exp, 0), 0);
3756 tree arglist = TREE_OPERAND (exp, 1);
3757 enum built_in_function fcode = DECL_FUNCTION_CODE (fndecl);
3758 enum tree_code code = TREE_CODE (exp);
3759 const int ignore = (target == const0_rtx
3760 || ((code == NON_LVALUE_EXPR || code == NOP_EXPR
3761 || code == CONVERT_EXPR || code == REFERENCE_EXPR
3762 || code == COND_EXPR)
3763 && TREE_CODE (type) == VOID_TYPE));
3765 if (! optimize && ! CALLED_AS_BUILT_IN (fndecl))
3766 return expand_call (exp, target, ignore);
3770 case BUILT_IN_PRINTF:
3771 target = c_expand_builtin_printf (arglist, target, tmode,
3772 modifier, ignore, /*unlocked=*/ 0);
3777 case BUILT_IN_PRINTF_UNLOCKED:
3778 target = c_expand_builtin_printf (arglist, target, tmode,
3779 modifier, ignore, /*unlocked=*/ 1);
3784 case BUILT_IN_FPRINTF:
3785 target = c_expand_builtin_fprintf (arglist, target, tmode,
3786 modifier, ignore, /*unlocked=*/ 0);
3791 case BUILT_IN_FPRINTF_UNLOCKED:
3792 target = c_expand_builtin_fprintf (arglist, target, tmode,
3793 modifier, ignore, /*unlocked=*/ 1);
3798 default: /* just do library call, if unknown builtin */
3799 error ("built-in function `%s' not currently supported",
3800 IDENTIFIER_POINTER (DECL_NAME (fndecl)));
3803 /* The switch statement above can drop through to cause the function
3804 to be called normally. */
3805 return expand_call (exp, target, ignore);
3808 /* Check an arglist to *printf for problems. The arglist should start
3809 at the format specifier, with the remaining arguments immediately
3812 is_valid_printf_arglist (arglist)
3815 /* Save this value so we can restore it later. */
3816 const int SAVE_pedantic = pedantic;
3817 int diagnostic_occurred = 0;
3820 /* Set this to a known value so the user setting won't affect code
3823 /* Check to make sure there are no format specifier errors. */
3824 attrs = tree_cons (get_identifier ("format"),
3825 tree_cons (NULL_TREE,
3826 get_identifier ("printf"),
3827 tree_cons (NULL_TREE,
3829 tree_cons (NULL_TREE,
3833 check_function_format (&diagnostic_occurred, attrs, arglist);
3835 /* Restore the value of `pedantic'. */
3836 pedantic = SAVE_pedantic;
3838 /* If calling `check_function_format_ptr' produces a warning, we
3839 return false, otherwise we return true. */
3840 return ! diagnostic_occurred;
3843 /* If the arguments passed to printf are suitable for optimizations,
3844 we attempt to transform the call. */
3846 c_expand_builtin_printf (arglist, target, tmode, modifier, ignore, unlocked)
3849 enum machine_mode tmode;
3850 enum expand_modifier modifier;
3854 tree fn_putchar = unlocked ?
3855 built_in_decls[BUILT_IN_PUTCHAR_UNLOCKED] : built_in_decls[BUILT_IN_PUTCHAR];
3856 tree fn_puts = unlocked ?
3857 built_in_decls[BUILT_IN_PUTS_UNLOCKED] : built_in_decls[BUILT_IN_PUTS];
3858 tree fn, format_arg, stripped_string;
3860 /* If the return value is used, or the replacement _DECL isn't
3861 initialized, don't do the transformation. */
3862 if (!ignore || !fn_putchar || !fn_puts)
3865 /* Verify the required arguments in the original call. */
3867 || (TREE_CODE (TREE_TYPE (TREE_VALUE (arglist))) != POINTER_TYPE))
3870 /* Check the specifier vs. the parameters. */
3871 if (!is_valid_printf_arglist (arglist))
3874 format_arg = TREE_VALUE (arglist);
3875 stripped_string = format_arg;
3876 STRIP_NOPS (stripped_string);
3877 if (stripped_string && TREE_CODE (stripped_string) == ADDR_EXPR)
3878 stripped_string = TREE_OPERAND (stripped_string, 0);
3880 /* If the format specifier isn't a STRING_CST, punt. */
3881 if (TREE_CODE (stripped_string) != STRING_CST)
3884 /* OK! We can attempt optimization. */
3886 /* If the format specifier was "%s\n", call __builtin_puts(arg2). */
3887 if (strcmp (TREE_STRING_POINTER (stripped_string), "%s\n") == 0)
3889 arglist = TREE_CHAIN (arglist);
3892 /* If the format specifier was "%c", call __builtin_putchar (arg2). */
3893 else if (strcmp (TREE_STRING_POINTER (stripped_string), "%c") == 0)
3895 arglist = TREE_CHAIN (arglist);
3900 /* We can't handle anything else with % args or %% ... yet. */
3901 if (strchr (TREE_STRING_POINTER (stripped_string), '%'))
3904 /* If the resulting constant string has a length of 1, call
3905 putchar. Note, TREE_STRING_LENGTH includes the terminating
3906 NULL in its count. */
3907 if (TREE_STRING_LENGTH (stripped_string) == 2)
3909 /* Given printf("c"), (where c is any one character,)
3910 convert "c"[0] to an int and pass that to the replacement
3912 arglist = build_int_2 (TREE_STRING_POINTER (stripped_string)[0], 0);
3913 arglist = build_tree_list (NULL_TREE, arglist);
3917 /* If the resulting constant was "string\n", call
3918 __builtin_puts("string"). Ensure "string" has at least one
3919 character besides the trailing \n. Note, TREE_STRING_LENGTH
3920 includes the terminating NULL in its count. */
3921 else if (TREE_STRING_LENGTH (stripped_string) > 2
3922 && TREE_STRING_POINTER (stripped_string)
3923 [TREE_STRING_LENGTH (stripped_string) - 2] == '\n')
3925 /* Create a NULL-terminated string that's one char shorter
3926 than the original, stripping off the trailing '\n'. */
3927 const int newlen = TREE_STRING_LENGTH (stripped_string) - 1;
3928 char *newstr = (char *) alloca (newlen);
3929 memcpy (newstr, TREE_STRING_POINTER (stripped_string), newlen - 1);
3930 newstr[newlen - 1] = 0;
3932 arglist = combine_strings (build_string (newlen, newstr));
3933 arglist = build_tree_list (NULL_TREE, arglist);
3937 /* We'd like to arrange to call fputs(string) here, but we
3938 need stdout and don't have a way to get it ... yet. */
3942 return expand_expr (build_function_call (fn, arglist),
3943 (ignore ? const0_rtx : target),
3947 /* If the arguments passed to fprintf are suitable for optimizations,
3948 we attempt to transform the call. */
3950 c_expand_builtin_fprintf (arglist, target, tmode, modifier, ignore, unlocked)
3953 enum machine_mode tmode;
3954 enum expand_modifier modifier;
3958 tree fn_fputc = unlocked ?
3959 built_in_decls[BUILT_IN_FPUTC_UNLOCKED] : built_in_decls[BUILT_IN_FPUTC];
3960 tree fn_fputs = unlocked ?
3961 built_in_decls[BUILT_IN_FPUTS_UNLOCKED] : built_in_decls[BUILT_IN_FPUTS];
3962 tree fn, format_arg, stripped_string;
3964 /* If the return value is used, or the replacement _DECL isn't
3965 initialized, don't do the transformation. */
3966 if (!ignore || !fn_fputc || !fn_fputs)
3969 /* Verify the required arguments in the original call. */
3971 || (TREE_CODE (TREE_TYPE (TREE_VALUE (arglist))) != POINTER_TYPE)
3972 || (TREE_CHAIN (arglist) == 0)
3973 || (TREE_CODE (TREE_TYPE (TREE_VALUE (TREE_CHAIN (arglist)))) !=
3977 /* Check the specifier vs. the parameters. */
3978 if (!is_valid_printf_arglist (TREE_CHAIN (arglist)))
3981 format_arg = TREE_VALUE (TREE_CHAIN (arglist));
3982 stripped_string = format_arg;
3983 STRIP_NOPS (stripped_string);
3984 if (stripped_string && TREE_CODE (stripped_string) == ADDR_EXPR)
3985 stripped_string = TREE_OPERAND (stripped_string, 0);
3987 /* If the format specifier isn't a STRING_CST, punt. */
3988 if (TREE_CODE (stripped_string) != STRING_CST)
3991 /* OK! We can attempt optimization. */
3993 /* If the format specifier was "%s", call __builtin_fputs(arg3, arg1). */
3994 if (strcmp (TREE_STRING_POINTER (stripped_string), "%s") == 0)
3996 tree newarglist = build_tree_list (NULL_TREE, TREE_VALUE (arglist));
3997 arglist = tree_cons (NULL_TREE,
3998 TREE_VALUE (TREE_CHAIN (TREE_CHAIN (arglist))),
4002 /* If the format specifier was "%c", call __builtin_fputc (arg3, arg1). */
4003 else if (strcmp (TREE_STRING_POINTER (stripped_string), "%c") == 0)
4005 tree newarglist = build_tree_list (NULL_TREE, TREE_VALUE (arglist));
4006 arglist = tree_cons (NULL_TREE,
4007 TREE_VALUE (TREE_CHAIN (TREE_CHAIN (arglist))),
4013 /* We can't handle anything else with % args or %% ... yet. */
4014 if (strchr (TREE_STRING_POINTER (stripped_string), '%'))
4017 /* When "string" doesn't contain %, replace all cases of
4018 fprintf(stream,string) with fputs(string,stream). The fputs
4019 builtin will take take of special cases like length==1. */
4020 arglist = tree_cons (NULL_TREE, TREE_VALUE (TREE_CHAIN (arglist)),
4021 build_tree_list (NULL_TREE, TREE_VALUE (arglist)));
4025 return expand_expr (build_function_call (fn, arglist),
4026 (ignore ? const0_rtx : target),
4031 /* Given a boolean expression ARG, return a tree representing an increment
4032 or decrement (as indicated by CODE) of ARG. The front end must check for
4033 invalid cases (e.g., decrement in C++). */
4035 boolean_increment (code, arg)
4036 enum tree_code code;
4040 tree true_res = (c_language == clk_cplusplus
4042 : c_bool_true_node);
4043 arg = stabilize_reference (arg);
4046 case PREINCREMENT_EXPR:
4047 val = build (MODIFY_EXPR, TREE_TYPE (arg), arg, true_res);
4049 case POSTINCREMENT_EXPR:
4050 val = build (MODIFY_EXPR, TREE_TYPE (arg), arg, true_res);
4051 arg = save_expr (arg);
4052 val = build (COMPOUND_EXPR, TREE_TYPE (arg), val, arg);
4053 val = build (COMPOUND_EXPR, TREE_TYPE (arg), arg, val);
4055 case PREDECREMENT_EXPR:
4056 val = build (MODIFY_EXPR, TREE_TYPE (arg), arg, invert_truthvalue (arg));
4058 case POSTDECREMENT_EXPR:
4059 val = build (MODIFY_EXPR, TREE_TYPE (arg), arg, invert_truthvalue (arg));
4060 arg = save_expr (arg);
4061 val = build (COMPOUND_EXPR, TREE_TYPE (arg), val, arg);
4062 val = build (COMPOUND_EXPR, TREE_TYPE (arg), arg, val);
4067 TREE_SIDE_EFFECTS (val) = 1;
4071 /* Handle C and C++ default attributes. */
4073 enum built_in_attribute
4075 #define DEF_ATTR_NULL_TREE(ENUM) ENUM,
4076 #define DEF_ATTR_INT(ENUM, VALUE) ENUM,
4077 #define DEF_ATTR_IDENT(ENUM, STRING) ENUM,
4078 #define DEF_ATTR_TREE_LIST(ENUM, PURPOSE, VALUE, CHAIN) ENUM,
4079 #define DEF_FN_ATTR(NAME, ATTRS, PREDICATE) /* No entry needed in enum. */
4080 #include "builtin-attrs.def"
4081 #undef DEF_ATTR_NULL_TREE
4083 #undef DEF_ATTR_IDENT
4084 #undef DEF_ATTR_TREE_LIST
4089 static tree built_in_attributes[(int) ATTR_LAST];
4091 static bool c_attrs_initialized = false;
4093 static void c_init_attributes PARAMS ((void));
4095 /* Common initialization before parsing options. */
4097 c_common_init_options (lang)
4098 enum c_language_kind lang;
4101 parse_in = cpp_create_reader (lang == clk_c ? CLK_GNUC89:
4102 lang == clk_cplusplus ? CLK_GNUCXX: CLK_OBJC);
4104 /* Mark as "unspecified" (see c_common_post_options). */
4105 flag_bounds_check = -1;
4108 /* Post-switch processing. */
4110 c_common_post_options ()
4112 cpp_post_options (parse_in);
4114 /* Save no-inline information we may clobber below. */
4115 flag_really_no_inline = flag_no_inline;
4117 flag_inline_trees = 1;
4119 /* Use tree inlining if possible. Function instrumentation is only
4120 done in the RTL level, so we disable tree inlining. */
4121 if (! flag_instrument_function_entry_exit)
4123 if (!flag_no_inline)
4125 if (flag_inline_functions)
4127 flag_inline_trees = 2;
4128 flag_inline_functions = 0;
4132 /* If still "unspecified", make it match -fbounded-pointers. */
4133 if (flag_bounds_check == -1)
4134 flag_bounds_check = flag_bounded_pointers;
4136 /* Special format checking options don't work without -Wformat; warn if
4138 if (warn_format_y2k && !warn_format)
4139 warning ("-Wformat-y2k ignored without -Wformat");
4140 if (warn_format_extra_args && !warn_format)
4141 warning ("-Wformat-extra-args ignored without -Wformat");
4142 if (warn_format_nonliteral && !warn_format)
4143 warning ("-Wformat-nonliteral ignored without -Wformat");
4144 if (warn_format_security && !warn_format)
4145 warning ("-Wformat-security ignored without -Wformat");
4146 if (warn_missing_format_attribute && !warn_format)
4147 warning ("-Wmissing-format-attribute ignored without -Wformat");
4150 /* Front end initialization common to C, ObjC and C++. */
4152 c_common_init (filename)
4153 const char *filename;
4155 /* NULL is passed up to toplev.c and we exit quickly. */
4156 if (flag_preprocess_only)
4158 cpp_preprocess_file (parse_in);
4162 /* Do this before initializing pragmas, as then cpplib's hash table
4164 filename = init_c_lex (filename);
4168 if (!c_attrs_initialized)
4169 c_init_attributes ();
4174 /* Common finish hook for the C, ObjC and C++ front ends. */
4178 cpp_finish (parse_in);
4180 /* For performance, avoid tearing down cpplib's internal structures.
4181 Call cpp_errors () instead of cpp_destroy (). */
4182 errorcount += cpp_errors (parse_in);
4186 c_init_attributes ()
4188 /* Fill in the built_in_attributes array. */
4189 #define DEF_ATTR_NULL_TREE(ENUM) \
4190 built_in_attributes[(int) ENUM] = NULL_TREE;
4191 #define DEF_ATTR_INT(ENUM, VALUE) \
4192 built_in_attributes[(int) ENUM] = build_int_2 (VALUE, VALUE < 0 ? -1 : 0);
4193 #define DEF_ATTR_IDENT(ENUM, STRING) \
4194 built_in_attributes[(int) ENUM] = get_identifier (STRING);
4195 #define DEF_ATTR_TREE_LIST(ENUM, PURPOSE, VALUE, CHAIN) \
4196 built_in_attributes[(int) ENUM] \
4197 = tree_cons (built_in_attributes[(int) PURPOSE], \
4198 built_in_attributes[(int) VALUE], \
4199 built_in_attributes[(int) CHAIN]);
4200 #define DEF_FN_ATTR(NAME, ATTRS, PREDICATE) /* No initialization needed. */
4201 #include "builtin-attrs.def"
4202 #undef DEF_ATTR_NULL_TREE
4204 #undef DEF_ATTR_IDENT
4205 #undef DEF_ATTR_TREE_LIST
4207 ggc_add_tree_root (built_in_attributes, (int) ATTR_LAST);
4208 c_attrs_initialized = true;
4211 /* Depending on the name of DECL, apply default attributes to it. */
4214 c_common_insert_default_attributes (decl)
4217 tree name = DECL_NAME (decl);
4219 if (!c_attrs_initialized)
4220 c_init_attributes ();
4222 #define DEF_ATTR_NULL_TREE(ENUM) /* Nothing needed after initialization. */
4223 #define DEF_ATTR_INT(ENUM, VALUE)
4224 #define DEF_ATTR_IDENT(ENUM, STRING)
4225 #define DEF_ATTR_TREE_LIST(ENUM, PURPOSE, VALUE, CHAIN)
4226 #define DEF_FN_ATTR(NAME, ATTRS, PREDICATE) \
4227 if ((PREDICATE) && name == built_in_attributes[(int) NAME]) \
4228 decl_attributes (&decl, built_in_attributes[(int) ATTRS], \
4229 ATTR_FLAG_BUILT_IN);
4230 #include "builtin-attrs.def"
4231 #undef DEF_ATTR_NULL_TREE
4233 #undef DEF_ATTR_IDENT
4234 #undef DEF_ATTR_TREE_LIST
4238 /* Output a -Wshadow warning MSGID about NAME, an IDENTIFIER_NODE, and
4239 additionally give the location of the previous declaration DECL. */
4241 shadow_warning (msgid, name, decl)
4245 warning ("declaration of `%s' shadows %s", IDENTIFIER_POINTER (name), msgid);
4246 warning_with_file_and_line (DECL_SOURCE_FILE (decl),
4247 DECL_SOURCE_LINE (decl),
4248 "shadowed declaration is here");