1 /* Declarations and definitions dealing with attribute handling. 2 Copyright (C) 2013-2018 Free Software Foundation, Inc. 3 4 This file is part of GCC. 5 6 GCC is free software; you can redistribute it and/or modify it under 7 the terms of the GNU General Public License as published by the Free 8 Software Foundation; either version 3, or (at your option) any later 9 version. 10 11 GCC is distributed in the hope that it will be useful, but WITHOUT ANY 12 WARRANTY; without even the implied warranty of MERCHANTABILITY or 13 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 14 for more details. 15 16 You should have received a copy of the GNU General Public License 17 along with GCC; see the file COPYING3. If not see 18 <http://www.gnu.org/licenses/>. */ 19 20 #ifndef GCC_ATTRIBS_H 21 #define GCC_ATTRIBS_H 22 23 extern const struct attribute_spec *lookup_attribute_spec (const_tree); 24 extern void init_attributes (void); 25 26 /* Process the attributes listed in ATTRIBUTES and install them in *NODE, 27 which is either a DECL (including a TYPE_DECL) or a TYPE. If a DECL, 28 it should be modified in place; if a TYPE, a copy should be created 29 unless ATTR_FLAG_TYPE_IN_PLACE is set in FLAGS. FLAGS gives further 30 information, in the form of a bitwise OR of flags in enum attribute_flags 31 from tree.h. Depending on these flags, some attributes may be 32 returned to be applied at a later stage (for example, to apply 33 a decl attribute to the declaration rather than to its type). */ 34 extern tree decl_attributes (tree *, tree, int, tree = NULL_TREE); 35 36 extern bool cxx11_attribute_p (const_tree); 37 extern tree get_attribute_name (const_tree); 38 extern void apply_tm_attr (tree, tree); 39 extern tree make_attribute (const char *, const char *, tree); 40 41 extern struct scoped_attributes* register_scoped_attributes (const struct attribute_spec *, 42 const char *); 43 44 extern char *sorted_attr_string (tree); 45 extern bool common_function_versions (tree, tree); 46 extern char *make_unique_name (tree, const char *, bool); 47 extern tree make_dispatcher_decl (const tree); 48 extern bool is_function_default_version (const tree); 49 50 /* Return a type like TTYPE except that its TYPE_ATTRIBUTES 51 is ATTRIBUTE. 52 53 Such modified types already made are recorded so that duplicates 54 are not made. */ 55 56 extern tree build_type_attribute_variant (tree, tree); 57 extern tree build_decl_attribute_variant (tree, tree); 58 extern tree build_type_attribute_qual_variant (tree, tree, int); 59 60 extern bool attribute_value_equal (const_tree, const_tree); 61 62 /* Return 0 if the attributes for two types are incompatible, 1 if they 63 are compatible, and 2 if they are nearly compatible (which causes a 64 warning to be generated). */ 65 extern int comp_type_attributes (const_tree, const_tree); 66 67 /* Default versions of target-overridable functions. */ 68 extern tree merge_decl_attributes (tree, tree); 69 extern tree merge_type_attributes (tree, tree); 70 71 /* Remove any instances of attribute ATTR_NAME in LIST and return the 72 modified list. */ 73 74 extern tree remove_attribute (const char *, tree); 75 76 /* Given two attributes lists, return a list of their union. */ 77 78 extern tree merge_attributes (tree, tree); 79 80 /* Duplicate all attributes with name NAME in ATTR list to *ATTRS if 81 they are missing there. */ 82 83 extern void duplicate_one_attribute (tree *, tree, const char *); 84 85 /* Duplicate all attributes from user DECL to the corresponding 86 builtin that should be propagated. */ 87 88 extern void copy_attributes_to_builtin (tree); 89 90 /* Given two Windows decl attributes lists, possibly including 91 dllimport, return a list of their union . */ 92 extern tree merge_dllimport_decl_attributes (tree, tree); 93 94 /* Handle a "dllimport" or "dllexport" attribute. */ 95 extern tree handle_dll_attribute (tree *, tree, tree, int, bool *); 96 97 extern int attribute_list_equal (const_tree, const_tree); 98 extern int attribute_list_contained (const_tree, const_tree); 99 100 /* The backbone of lookup_attribute(). ATTR_LEN is the string length 101 of ATTR_NAME, and LIST is not NULL_TREE. 102 103 The function is called from lookup_attribute in order to optimize 104 for size. */ 105 extern tree private_lookup_attribute (const char *attr_name, size_t attr_len, 106 tree list); 107 108 /* For a given IDENTIFIER_NODE, strip leading and trailing '_' characters 109 so that we have a canonical form of attribute names. */ 110 111 static inline tree 112 canonicalize_attr_name (tree attr_name) 113 { 114 const size_t l = IDENTIFIER_LENGTH (attr_name); 115 const char *s = IDENTIFIER_POINTER (attr_name); 116 117 if (l > 4 && s[0] == '_' && s[1] == '_' && s[l - 1] == '_' && s[l - 2] == '_') 118 return get_identifier_with_length (s + 2, l - 4); 119 120 return attr_name; 121 } 122 123 /* Compare attribute identifiers ATTR1 and ATTR2 with length ATTR1_LEN and 124 ATTR2_LEN. */ 125 126 static inline bool 127 cmp_attribs (const char *attr1, size_t attr1_len, 128 const char *attr2, size_t attr2_len) 129 { 130 return attr1_len == attr2_len && strncmp (attr1, attr2, attr1_len) == 0; 131 } 132 133 /* Compare attribute identifiers ATTR1 and ATTR2. */ 134 135 static inline bool 136 cmp_attribs (const char *attr1, const char *attr2) 137 { 138 return cmp_attribs (attr1, strlen (attr1), attr2, strlen (attr2)); 139 } 140 141 /* Given an identifier node IDENT and a string ATTR_NAME, return true 142 if the identifier node is a valid attribute name for the string. */ 143 144 static inline bool 145 is_attribute_p (const char *attr_name, const_tree ident) 146 { 147 return cmp_attribs (attr_name, strlen (attr_name), 148 IDENTIFIER_POINTER (ident), IDENTIFIER_LENGTH (ident)); 149 } 150 151 /* Given an attribute name ATTR_NAME and a list of attributes LIST, 152 return a pointer to the attribute's list element if the attribute 153 is part of the list, or NULL_TREE if not found. If the attribute 154 appears more than once, this only returns the first occurrence; the 155 TREE_CHAIN of the return value should be passed back in if further 156 occurrences are wanted. ATTR_NAME must be in the form 'text' (not 157 '__text__'). */ 158 159 static inline tree 160 lookup_attribute (const char *attr_name, tree list) 161 { 162 gcc_checking_assert (attr_name[0] != '_'); 163 /* In most cases, list is NULL_TREE. */ 164 if (list == NULL_TREE) 165 return NULL_TREE; 166 else 167 { 168 size_t attr_len = strlen (attr_name); 169 /* Do the strlen() before calling the out-of-line implementation. 170 In most cases attr_name is a string constant, and the compiler 171 will optimize the strlen() away. */ 172 return private_lookup_attribute (attr_name, attr_len, list); 173 } 174 } 175 176 /* Given an attribute name ATTR_NAME and a list of attributes LIST, 177 return a pointer to the attribute's list first element if the attribute 178 starts with ATTR_NAME. ATTR_NAME must be in the form 'text' (not 179 '__text__'). */ 180 181 static inline tree 182 lookup_attribute_by_prefix (const char *attr_name, tree list) 183 { 184 gcc_checking_assert (attr_name[0] != '_'); 185 /* In most cases, list is NULL_TREE. */ 186 if (list == NULL_TREE) 187 return NULL_TREE; 188 else 189 { 190 size_t attr_len = strlen (attr_name); 191 while (list) 192 { 193 size_t ident_len = IDENTIFIER_LENGTH (get_attribute_name (list)); 194 195 if (attr_len > ident_len) 196 { 197 list = TREE_CHAIN (list); 198 continue; 199 } 200 201 const char *p = IDENTIFIER_POINTER (get_attribute_name (list)); 202 gcc_checking_assert (attr_len == 0 || p[0] != '_'); 203 204 if (strncmp (attr_name, p, attr_len) == 0) 205 break; 206 207 list = TREE_CHAIN (list); 208 } 209 210 return list; 211 } 212 } 213 214 #endif // GCC_ATTRIBS_H 215