gcc/cp/mangle.c

   1 /* Name mangling for the 3.0 C++ ABI.
   2    Copyright (C) 2000-2013 Free Software Foundation, Inc.
   3    Written by Alex Samuel <samuel@codesourcery.com>
   4
   5    This file is part of GCC.
   6
   7    GCC is free software; you can redistribute it and/or modify it
   8    under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 3, or (at your option)
  10    any later version.
  11
  12    GCC is distributed in the hope that it will be useful, but
  13    WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15    General Public License for more details.
  16
  17 You should have received a copy of the GNU General Public License
  18 along with GCC; see the file COPYING3.  If not see
  19 <http://www.gnu.org/licenses/>.  */
  20
  21 /* This file implements mangling of C++ names according to the IA64
  22    C++ ABI specification.  A mangled name encodes a function or
  23    variable's name, scope, type, and/or template arguments into a text
  24    identifier.  This identifier is used as the function's or
  25    variable's linkage name, to preserve compatibility between C++'s
  26    language features (templates, scoping, and overloading) and C
  27    linkers.
  28
  29    Additionally, g++ uses mangled names internally.  To support this,
  30    mangling of types is allowed, even though the mangled name of a
  31    type should not appear by itself as an exported name.  Ditto for
  32    uninstantiated templates.
  33
  34    The primary entry point for this module is mangle_decl, which
  35    returns an identifier containing the mangled name for a decl.
  36    Additional entry points are provided to build mangled names of
  37    particular constructs when the appropriate decl for that construct
  38    is not available.  These are:
  39
  40      mangle_typeinfo_for_type:          typeinfo data
  41      mangle_typeinfo_string_for_type:   typeinfo type name
  42      mangle_vtbl_for_type:              virtual table data
  43      mangle_vtt_for_type:               VTT data
  44      mangle_ctor_vtbl_for_type:         `C-in-B' constructor virtual table data
  45      mangle_thunk:                      thunk function or entry  */
  46
  47 #include "config.h"
  48 #include "system.h"
  49 #include "coretypes.h"
  50 #include "tm.h"
  51 #include "tree.h"
  52 #include "tm_p.h"
  53 #include "cp-tree.h"
  54 #include "obstack.h"
  55 #include "flags.h"
  56 #include "target.h"
  57 #include "cgraph.h"
  58
  59 /* Debugging support.  */
  60
  61 /* Define DEBUG_MANGLE to enable very verbose trace messages.  */
  62 #ifndef DEBUG_MANGLE
  63 #define DEBUG_MANGLE 0
  64 #endif
  65
  66 /* Macros for tracing the write_* functions.  */
  67 #if DEBUG_MANGLE
  68 # define MANGLE_TRACE(FN, INPUT) \
  69   fprintf (stderr, "  %-24s: %-24s\n", (FN), (INPUT))
  70 # define MANGLE_TRACE_TREE(FN, NODE) \
  71   fprintf (stderr, "  %-24s: %-24s (%p)\n", \
  72            (FN), tree_code_name[TREE_CODE (NODE)], (void *) (NODE))
  73 #else
  74 # define MANGLE_TRACE(FN, INPUT)
  75 # define MANGLE_TRACE_TREE(FN, NODE)
  76 #endif
  77
  78 /* Nonzero if NODE is a class template-id.  We can't rely on
  79    CLASSTYPE_USE_TEMPLATE here because of tricky bugs in the parser
  80    that hard to distinguish A<T> from A, where A<T> is the type as
  81    instantiated outside of the template, and A is the type used
  82    without parameters inside the template.  */
  83 #define CLASSTYPE_TEMPLATE_ID_P(NODE)                                   \
  84   (TYPE_LANG_SPECIFIC (NODE) != NULL                                    \
  85    && (TREE_CODE (NODE) == BOUND_TEMPLATE_TEMPLATE_PARM                 \
  86        || (CLASSTYPE_TEMPLATE_INFO (NODE) != NULL                       \
  87            && (PRIMARY_TEMPLATE_P (CLASSTYPE_TI_TEMPLATE (NODE))))))
  88
  89 /* Things we only need one of.  This module is not reentrant.  */
  90 typedef struct GTY(()) globals {
  91   /* An array of the current substitution candidates, in the order
  92      we've seen them.  */
  93   vec<tree, va_gc> *substitutions;
  94
  95   /* The entity that is being mangled.  */
  96   tree GTY ((skip)) entity;
  97
  98   /* How many parameter scopes we are inside.  */
  99   int parm_depth;
 100
 101   /* True if the mangling will be different in a future version of the
 102      ABI.  */
 103   bool need_abi_warning;
 104 } globals;
 105
 106 static GTY (()) globals G;
 107
 108 /* The obstack on which we build mangled names.  */
 109 static struct obstack *mangle_obstack;
 110
 111 /* The obstack on which we build mangled names that are not going to
 112    be IDENTIFIER_NODEs.  */
 113 static struct obstack name_obstack;
 114
 115 /* The first object on the name_obstack; we use this to free memory
 116    allocated on the name_obstack.  */
 117 static void *name_base;
 118
 119 /* Indices into subst_identifiers.  These are identifiers used in
 120    special substitution rules.  */
 121 typedef enum
 122 {
 123   SUBID_ALLOCATOR,
 124   SUBID_BASIC_STRING,
 125   SUBID_CHAR_TRAITS,
 126   SUBID_BASIC_ISTREAM,
 127   SUBID_BASIC_OSTREAM,
 128   SUBID_BASIC_IOSTREAM,
 129   SUBID_MAX
 130 }
 131 substitution_identifier_index_t;
 132
 133 /* For quick substitution checks, look up these common identifiers
 134    once only.  */
 135 static GTY(()) tree subst_identifiers[SUBID_MAX];
 136
 137 /* Single-letter codes for builtin integer types, defined in
 138    <builtin-type>.  These are indexed by integer_type_kind values.  */
 139 static const char
 140 integer_type_codes[itk_none] =
 141 {
 142   'c',  /* itk_char */
 143   'a',  /* itk_signed_char */
 144   'h',  /* itk_unsigned_char */
 145   's',  /* itk_short */
 146   't',  /* itk_unsigned_short */
 147   'i',  /* itk_int */
 148   'j',  /* itk_unsigned_int */
 149   'l',  /* itk_long */
 150   'm',  /* itk_unsigned_long */
 151   'x',  /* itk_long_long */
 152   'y',  /* itk_unsigned_long_long */
 153   'n',  /* itk_int128 */
 154   'o',  /* itk_unsigned_int128  */
 155 };
 156
 157 static int decl_is_template_id (const tree, tree* const);
 158
 159 /* Functions for handling substitutions.  */
 160
 161 static inline tree canonicalize_for_substitution (tree);
 162 static void add_substitution (tree);
 163 static inline int is_std_substitution (const tree,
 164                                        const substitution_identifier_index_t);
 165 static inline int is_std_substitution_char (const tree,
 166                                             const substitution_identifier_index_t);
 167 static int find_substitution (tree);
 168 static void mangle_call_offset (const tree, const tree);
 169
 170 /* Functions for emitting mangled representations of things.  */
 171
 172 static void write_mangled_name (const tree, bool);
 173 static void write_encoding (const tree);
 174 static void write_name (tree, const int);
 175 static void write_abi_tags (tree);
 176 static void write_unscoped_name (const tree);
 177 static void write_unscoped_template_name (const tree);
 178 static void write_nested_name (const tree);
 179 static void write_prefix (const tree);
 180 static void write_template_prefix (const tree);
 181 static void write_unqualified_name (const tree);
 182 static void write_conversion_operator_name (const tree);
 183 static void write_source_name (tree);
 184 static void write_literal_operator_name (tree);
 185 static void write_unnamed_type_name (const tree);
 186 static void write_closure_type_name (const tree);
 187 static int hwint_to_ascii (unsigned HOST_WIDE_INT, const unsigned int, char *,
 188                            const unsigned int);
 189 static void write_number (unsigned HOST_WIDE_INT, const int,
 190                           const unsigned int);
 191 static void write_compact_number (int num);
 192 static void write_integer_cst (const tree);
 193 static void write_real_cst (const tree);
 194 static void write_identifier (const char *);
 195 static void write_special_name_constructor (const tree);
 196 static void write_special_name_destructor (const tree);
 197 static void write_type (tree);
 198 static int write_CV_qualifiers_for_type (const tree);
 199 static void write_builtin_type (tree);
 200 static void write_function_type (const tree);
 201 static void write_bare_function_type (const tree, const int, const tree);
 202 static void write_method_parms (tree, const int, const tree);
 203 static void write_class_enum_type (const tree);
 204 static void write_template_args (tree);
 205 static void write_expression (tree);
 206 static void write_template_arg_literal (const tree);
 207 static void write_template_arg (tree);
 208 static void write_template_template_arg (const tree);
 209 static void write_array_type (const tree);
 210 static void write_pointer_to_member_type (const tree);
 211 static void write_template_param (const tree);
 212 static void write_template_template_param (const tree);
 213 static void write_substitution (const int);
 214 static int discriminator_for_local_entity (tree);
 215 static int discriminator_for_string_literal (tree, tree);
 216 static void write_discriminator (const int);
 217 static void write_local_name (tree, const tree, const tree);
 218 static void dump_substitution_candidates (void);
 219 static tree mangle_decl_string (const tree);
 220 static int local_class_index (tree);
 221
 222 /* Control functions.  */
 223
 224 static inline void start_mangling (const tree);
 225 static inline const char *finish_mangling (const bool);
 226 static tree mangle_special_for_type (const tree, const char *);
 227
 228 /* Foreign language functions.  */
 229
 230 static void write_java_integer_type_codes (const tree);
 231
 232 /* Append a single character to the end of the mangled
 233    representation.  */
 234 #define write_char(CHAR)                                                \
 235   obstack_1grow (mangle_obstack, (CHAR))
 236
 237 /* Append a sized buffer to the end of the mangled representation.  */
 238 #define write_chars(CHAR, LEN)                                          \
 239   obstack_grow (mangle_obstack, (CHAR), (LEN))
 240
 241 /* Append a NUL-terminated string to the end of the mangled
 242    representation.  */
 243 #define write_string(STRING)                                            \
 244   obstack_grow (mangle_obstack, (STRING), strlen (STRING))
 245
 246 /* Nonzero if NODE1 and NODE2 are both TREE_LIST nodes and have the
 247    same purpose (context, which may be a type) and value (template
 248    decl).  See write_template_prefix for more information on what this
 249    is used for.  */
 250 #define NESTED_TEMPLATE_MATCH(NODE1, NODE2)                             \
 251   (TREE_CODE (NODE1) == TREE_LIST                                       \
 252    && TREE_CODE (NODE2) == TREE_LIST                                    \
 253    && ((TYPE_P (TREE_PURPOSE (NODE1))                                   \
 254         && same_type_p (TREE_PURPOSE (NODE1), TREE_PURPOSE (NODE2)))    \
 255        || TREE_PURPOSE (NODE1) == TREE_PURPOSE (NODE2))                 \
 256    && TREE_VALUE (NODE1) == TREE_VALUE (NODE2))
 257
 258 /* Write out an unsigned quantity in base 10.  */
 259 #define write_unsigned_number(NUMBER)                                   \
 260   write_number ((NUMBER), /*unsigned_p=*/1, 10)
 261
 262 /* If DECL is a template instance, return nonzero and, if
 263    TEMPLATE_INFO is non-NULL, set *TEMPLATE_INFO to its template info.
 264    Otherwise return zero.  */
 265
 266 static int
 267 decl_is_template_id (const tree decl, tree* const template_info)
 268 {
 269   if (TREE_CODE (decl) == TYPE_DECL)
 270     {
 271       /* TYPE_DECLs are handled specially.  Look at its type to decide
 272          if this is a template instantiation.  */
 273       const tree type = TREE_TYPE (decl);
 274
 275       if (CLASS_TYPE_P (type) && CLASSTYPE_TEMPLATE_ID_P (type))
 276         {
 277           if (template_info != NULL)
 278             /* For a templated TYPE_DECL, the template info is hanging
 279                off the type.  */
 280             *template_info = TYPE_TEMPLATE_INFO (type);
 281           return 1;
 282         }
 283     }
 284   else
 285     {
 286       /* Check if this is a primary template.  */
 287       if (DECL_LANG_SPECIFIC (decl) != NULL
 288           && DECL_USE_TEMPLATE (decl)
 289           && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (decl))
 290           && TREE_CODE (decl) != TEMPLATE_DECL)
 291         {
 292           if (template_info != NULL)
 293             /* For most templated decls, the template info is hanging
 294                off the decl.  */
 295             *template_info = DECL_TEMPLATE_INFO (decl);
 296           return 1;
 297         }
 298     }
 299
 300   /* It's not a template id.  */
 301   return 0;
 302 }
 303
 304 /* Produce debugging output of current substitution candidates.  */
 305
 306 static void
 307 dump_substitution_candidates (void)
 308 {
 309   unsigned i;
 310   tree el;
 311
 312   fprintf (stderr, "  ++ substitutions  ");
 313   FOR_EACH_VEC_ELT (*G.substitutions, i, el)
 314     {
 315       const char *name = "???";
 316
 317       if (i > 0)
 318         fprintf (stderr, "                    ");
 319       if (DECL_P (el))
 320         name = IDENTIFIER_POINTER (DECL_NAME (el));
 321       else if (TREE_CODE (el) == TREE_LIST)
 322         name = IDENTIFIER_POINTER (DECL_NAME (TREE_VALUE (el)));
 323       else if (TYPE_NAME (el))
 324         name = IDENTIFIER_POINTER (DECL_NAME (TYPE_NAME (el)));
 325       fprintf (stderr, " S%d_ = ", i - 1);
 326       if (TYPE_P (el) &&
 327           (CP_TYPE_RESTRICT_P (el)
 328            || CP_TYPE_VOLATILE_P (el)
 329            || CP_TYPE_CONST_P (el)))
 330         fprintf (stderr, "CV-");
 331       fprintf (stderr, "%s (%s at %p)\n",
 332                name, tree_code_name[TREE_CODE (el)], (void *) el);
 333     }
 334 }
 335
 336 /* Both decls and types can be substitution candidates, but sometimes
 337    they refer to the same thing.  For instance, a TYPE_DECL and
 338    RECORD_TYPE for the same class refer to the same thing, and should
 339    be treated accordingly in substitutions.  This function returns a
 340    canonicalized tree node representing NODE that is used when adding
 341    and substitution candidates and finding matches.  */
 342
 343 static inline tree
 344 canonicalize_for_substitution (tree node)
 345 {
 346   /* For a TYPE_DECL, use the type instead.  */
 347   if (TREE_CODE (node) == TYPE_DECL)
 348     node = TREE_TYPE (node);
 349   if (TYPE_P (node)
 350       && TYPE_CANONICAL (node) != node
 351       && TYPE_MAIN_VARIANT (node) != node)
 352     {
 353       /* Here we want to strip the topmost typedef only.
 354          We need to do that so is_std_substitution can do proper
 355          name matching.  */
 356       if (TREE_CODE (node) == FUNCTION_TYPE)
 357         /* Use build_qualified_type and TYPE_QUALS here to preserve
 358            the old buggy mangling of attribute noreturn with abi<5.  */
 359         node = build_qualified_type (TYPE_MAIN_VARIANT (node),
 360                                      TYPE_QUALS (node));
 361       else
 362         node = cp_build_qualified_type (TYPE_MAIN_VARIANT (node),
 363                                         cp_type_quals (node));
 364     }
 365   return node;
 366 }
 367
 368 /* Add NODE as a substitution candidate.  NODE must not already be on
 369    the list of candidates.  */
 370
 371 static void
 372 add_substitution (tree node)
 373 {
 374   tree c;
 375
 376   if (DEBUG_MANGLE)
 377     fprintf (stderr, "  ++ add_substitution (%s at %10p)\n",
 378              tree_code_name[TREE_CODE (node)], (void *) node);
 379
 380   /* Get the canonicalized substitution candidate for NODE.  */
 381   c = canonicalize_for_substitution (node);
 382   if (DEBUG_MANGLE && c != node)
 383     fprintf (stderr, "  ++ using candidate (%s at %10p)\n",
 384              tree_code_name[TREE_CODE (node)], (void *) node);
 385   node = c;
 386
 387 #if ENABLE_CHECKING
 388   /* Make sure NODE isn't already a candidate.  */
 389   {
 390     int i;
 391     tree candidate;
 392
 393     FOR_EACH_VEC_SAFE_ELT (G.substitutions, i, candidate)
 394       {
 395         gcc_assert (!(DECL_P (node) && node == candidate));
 396         gcc_assert (!(TYPE_P (node) && TYPE_P (candidate)
 397                       && same_type_p (node, candidate)));
 398       }
 399   }
 400 #endif /* ENABLE_CHECKING */
 401
 402   /* Put the decl onto the varray of substitution candidates.  */
 403   vec_safe_push (G.substitutions, node);
 404
 405   if (DEBUG_MANGLE)
 406     dump_substitution_candidates ();
 407 }
 408
 409 /* Helper function for find_substitution.  Returns nonzero if NODE,
 410    which may be a decl or a CLASS_TYPE, is a template-id with template
 411    name of substitution_index[INDEX] in the ::std namespace.  */
 412
 413 static inline int
 414 is_std_substitution (const tree node,
 415                      const substitution_identifier_index_t index)
 416 {
 417   tree type = NULL;
 418   tree decl = NULL;
 419
 420   if (DECL_P (node))
 421     {
 422       type = TREE_TYPE (node);
 423       decl = node;
 424     }
 425   else if (CLASS_TYPE_P (node))
 426     {
 427       type = node;
 428       decl = TYPE_NAME (node);
 429     }
 430   else
 431     /* These are not the droids you're looking for.  */
 432     return 0;
 433
 434   return (DECL_NAMESPACE_STD_P (CP_DECL_CONTEXT (decl))
 435           && TYPE_LANG_SPECIFIC (type)
 436           && TYPE_TEMPLATE_INFO (type)
 437           && (DECL_NAME (TYPE_TI_TEMPLATE (type))
 438               == subst_identifiers[index]));
 439 }
 440
 441 /* Helper function for find_substitution.  Returns nonzero if NODE,
 442    which may be a decl or a CLASS_TYPE, is the template-id
 443    ::std::identifier<char>, where identifier is
 444    substitution_index[INDEX].  */
 445
 446 static inline int
 447 is_std_substitution_char (const tree node,
 448                           const substitution_identifier_index_t index)
 449 {
 450   tree args;
 451   /* Check NODE's name is ::std::identifier.  */
 452   if (!is_std_substitution (node, index))
 453     return 0;
 454   /* Figure out its template args.  */
 455   if (DECL_P (node))
 456     args = DECL_TI_ARGS (node);
 457   else if (CLASS_TYPE_P (node))
 458     args = CLASSTYPE_TI_ARGS (node);
 459   else
 460     /* Oops, not a template.  */
 461     return 0;
 462   /* NODE's template arg list should be <char>.  */
 463   return
 464     TREE_VEC_LENGTH (args) == 1
 465     && TREE_VEC_ELT (args, 0) == char_type_node;
 466 }
 467
 468 /* Check whether a substitution should be used to represent NODE in
 469    the mangling.
 470
 471    First, check standard special-case substitutions.
 472
 473      <substitution> ::= St
 474          # ::std
 475
 476                     ::= Sa
 477          # ::std::allocator
 478
 479                     ::= Sb
 480          # ::std::basic_string
 481
 482                     ::= Ss
 483          # ::std::basic_string<char,
 484                                ::std::char_traits<char>,
 485                                ::std::allocator<char> >
 486
 487                     ::= Si
 488          # ::std::basic_istream<char, ::std::char_traits<char> >
 489
 490                     ::= So
 491          # ::std::basic_ostream<char, ::std::char_traits<char> >
 492
 493                     ::= Sd
 494          # ::std::basic_iostream<char, ::std::char_traits<char> >
 495
 496    Then examine the stack of currently available substitution
 497    candidates for entities appearing earlier in the same mangling
 498
 499    If a substitution is found, write its mangled representation and
 500    return nonzero.  If none is found, just return zero.  */
 501
 502 static int
 503 find_substitution (tree node)
 504 {
 505   int i;
 506   const int size = vec_safe_length (G.substitutions);
 507   tree decl;
 508   tree type;
 509
 510   if (DEBUG_MANGLE)
 511     fprintf (stderr, "  ++ find_substitution (%s at %p)\n",
 512              tree_code_name[TREE_CODE (node)], (void *) node);
 513
 514   /* Obtain the canonicalized substitution representation for NODE.
 515      This is what we'll compare against.  */
 516   node = canonicalize_for_substitution (node);
 517
 518   /* Check for builtin substitutions.  */
 519
 520   decl = TYPE_P (node) ? TYPE_NAME (node) : node;
 521   type = TYPE_P (node) ? node : TREE_TYPE (node);
 522
 523   /* Check for std::allocator.  */
 524   if (decl
 525       && is_std_substitution (decl, SUBID_ALLOCATOR)
 526       && !CLASSTYPE_USE_TEMPLATE (TREE_TYPE (decl)))
 527     {
 528       write_string ("Sa");
 529       return 1;
 530     }
 531
 532   /* Check for std::basic_string.  */
 533   if (decl && is_std_substitution (decl, SUBID_BASIC_STRING))
 534     {
 535       if (TYPE_P (node))
 536         {
 537           /* If this is a type (i.e. a fully-qualified template-id),
 538              check for
 539                  std::basic_string <char,
 540                                     std::char_traits<char>,
 541                                     std::allocator<char> > .  */
 542           if (cp_type_quals (type) == TYPE_UNQUALIFIED
 543               && CLASSTYPE_USE_TEMPLATE (type))
 544             {
 545               tree args = CLASSTYPE_TI_ARGS (type);
 546               if (TREE_VEC_LENGTH (args) == 3
 547                   && same_type_p (TREE_VEC_ELT (args, 0), char_type_node)
 548                   && is_std_substitution_char (TREE_VEC_ELT (args, 1),
 549                                                SUBID_CHAR_TRAITS)
 550                   && is_std_substitution_char (TREE_VEC_ELT (args, 2),
 551                                                SUBID_ALLOCATOR))
 552                 {
 553                   write_string ("Ss");
 554                   return 1;
 555                 }
 556             }
 557         }
 558       else
 559         /* Substitute for the template name only if this isn't a type.  */
 560         {
 561           write_string ("Sb");
 562           return 1;
 563         }
 564     }
 565
 566   /* Check for basic_{i,o,io}stream.  */
 567   if (TYPE_P (node)
 568       && cp_type_quals (type) == TYPE_UNQUALIFIED
 569       && CLASS_TYPE_P (type)
 570       && CLASSTYPE_USE_TEMPLATE (type)
 571       && CLASSTYPE_TEMPLATE_INFO (type) != NULL)
 572     {
 573       /* First, check for the template
 574          args <char, std::char_traits<char> > .  */
 575       tree args = CLASSTYPE_TI_ARGS (type);
 576       if (TREE_VEC_LENGTH (args) == 2
 577           && TYPE_P (TREE_VEC_ELT (args, 0))
 578           && same_type_p (TREE_VEC_ELT (args, 0), char_type_node)
 579           && is_std_substitution_char (TREE_VEC_ELT (args, 1),
 580                                        SUBID_CHAR_TRAITS))
 581         {
 582           /* Got them.  Is this basic_istream?  */
 583           if (is_std_substitution (decl, SUBID_BASIC_ISTREAM))
 584             {
 585               write_string ("Si");
 586               return 1;
 587             }
 588           /* Or basic_ostream?  */
 589           else if (is_std_substitution (decl, SUBID_BASIC_OSTREAM))
 590             {
 591               write_string ("So");
 592               return 1;
 593             }
 594           /* Or basic_iostream?  */
 595           else if (is_std_substitution (decl, SUBID_BASIC_IOSTREAM))
 596             {
 597               write_string ("Sd");
 598               return 1;
 599             }
 600         }
 601     }
 602
 603   /* Check for namespace std.  */
 604   if (decl && DECL_NAMESPACE_STD_P (decl))
 605     {
 606       write_string ("St");
 607       return 1;
 608     }
 609
 610   /* Now check the list of available substitutions for this mangling
 611      operation.  */
 612   for (i = 0; i < size; ++i)
 613     {
 614       tree candidate = (*G.substitutions)[i];
 615       /* NODE is a matched to a candidate if it's the same decl node or
 616          if it's the same type.  */
 617       if (decl == candidate
 618           || (TYPE_P (candidate) && type && TYPE_P (node)
 619               && same_type_p (type, candidate))
 620           || NESTED_TEMPLATE_MATCH (node, candidate))
 621         {
 622           write_substitution (i);
 623           return 1;
 624         }
 625     }
 626
 627   /* No substitution found.  */
 628   return 0;
 629 }
 630
 631
 632 /* TOP_LEVEL is true, if this is being called at outermost level of
 633   mangling. It should be false when mangling a decl appearing in an
 634   expression within some other mangling.
 635
 636   <mangled-name>      ::= _Z <encoding>  */
 637
 638 static void
 639 write_mangled_name (const tree decl, bool top_level)
 640 {
 641   MANGLE_TRACE_TREE ("mangled-name", decl);
 642
 643   if (/* The names of `extern "C"' functions are not mangled.  */
 644       DECL_EXTERN_C_FUNCTION_P (decl)
 645       /* But overloaded operator names *are* mangled.  */
 646       && !DECL_OVERLOADED_OPERATOR_P (decl))
 647     {
 648     unmangled_name:;
 649
 650       if (top_level)
 651         write_string (IDENTIFIER_POINTER (DECL_NAME (decl)));
 652       else
 653         {
 654           /* The standard notes: "The <encoding> of an extern "C"
 655              function is treated like global-scope data, i.e. as its
 656              <source-name> without a type."  We cannot write
 657              overloaded operators that way though, because it contains
 658              characters invalid in assembler.  */
 659           if (abi_version_at_least (2))
 660             write_string ("_Z");
 661           else
 662             G.need_abi_warning = true;
 663           write_source_name (DECL_NAME (decl));
 664         }
 665     }
 666   else if (TREE_CODE (decl) == VAR_DECL
 667            /* The names of non-static global variables aren't mangled.  */
 668            && DECL_EXTERNAL_LINKAGE_P (decl)
 669            && (CP_DECL_CONTEXT (decl) == global_namespace
 670                /* And neither are `extern "C"' variables.  */
 671                || DECL_EXTERN_C_P (decl)))
 672     {
 673       if (top_level || abi_version_at_least (2))
 674         goto unmangled_name;
 675       else
 676         {
 677           G.need_abi_warning = true;
 678           goto mangled_name;
 679         }
 680     }
 681   else
 682     {
 683     mangled_name:;
 684       write_string ("_Z");
 685       write_encoding (decl);
 686       if (DECL_LANG_SPECIFIC (decl)
 687           && (DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (decl)
 688               || DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (decl)))
 689         /* We need a distinct mangled name for these entities, but
 690            we should never actually output it.  So, we append some
 691            characters the assembler won't like.  */
 692         write_string (" *INTERNAL* ");
 693     }
 694 }
 695
 696 /*   <encoding>         ::= <function name> <bare-function-type>
 697                         ::= <data name>  */
 698
 699 static void
 700 write_encoding (const tree decl)
 701 {
 702   MANGLE_TRACE_TREE ("encoding", decl);
 703
 704   if (DECL_LANG_SPECIFIC (decl) && DECL_EXTERN_C_FUNCTION_P (decl))
 705     {
 706       /* For overloaded operators write just the mangled name
 707          without arguments.  */
 708       if (DECL_OVERLOADED_OPERATOR_P (decl))
 709         write_name (decl, /*ignore_local_scope=*/0);
 710       else
 711         write_source_name (DECL_NAME (decl));
 712       return;
 713     }
 714
 715   write_name (decl, /*ignore_local_scope=*/0);
 716   if (TREE_CODE (decl) == FUNCTION_DECL)
 717     {
 718       tree fn_type;
 719       tree d;
 720
 721       if (decl_is_template_id (decl, NULL))
 722         {
 723           fn_type = get_mostly_instantiated_function_type (decl);
 724           /* FN_TYPE will not have parameter types for in-charge or
 725              VTT parameters.  Therefore, we pass NULL_TREE to
 726              write_bare_function_type -- otherwise, it will get
 727              confused about which artificial parameters to skip.  */
 728           d = NULL_TREE;
 729         }
 730       else
 731         {
 732           fn_type = TREE_TYPE (decl);
 733           d = decl;
 734         }
 735
 736       write_bare_function_type (fn_type,
 737                                 (!DECL_CONSTRUCTOR_P (decl)
 738                                  && !DECL_DESTRUCTOR_P (decl)
 739                                  && !DECL_CONV_FN_P (decl)
 740                                  && decl_is_template_id (decl, NULL)),
 741                                 d);
 742     }
 743 }
 744
 745 /* Lambdas can have a bit more context for mangling, specifically VAR_DECL
 746    or PARM_DECL context, which doesn't belong in DECL_CONTEXT.  */
 747
 748 static tree
 749 decl_mangling_context (tree decl)
 750 {
 751   tree tcontext = targetm.cxx.decl_mangling_context (decl);
 752
 753   if (tcontext != NULL_TREE)
 754     return tcontext;
 755
 756   if (TREE_CODE (decl) == TYPE_DECL
 757       && LAMBDA_TYPE_P (TREE_TYPE (decl)))
 758     {
 759       tree extra = LAMBDA_TYPE_EXTRA_SCOPE (TREE_TYPE (decl));
 760       if (extra)
 761         return extra;
 762     }
 763     else if (TREE_CODE (decl) == TYPE_DECL
 764              && TREE_CODE (TREE_TYPE (decl)) == TEMPLATE_TYPE_PARM)
 765      /* template type parms have no mangling context.  */
 766       return NULL_TREE;
 767   return CP_DECL_CONTEXT (decl);
 768 }
 769
 770 /* <name> ::= <unscoped-name>
 771           ::= <unscoped-template-name> <template-args>
 772           ::= <nested-name>
 773           ::= <local-name>
 774
 775    If IGNORE_LOCAL_SCOPE is nonzero, this production of <name> is
 776    called from <local-name>, which mangles the enclosing scope
 777    elsewhere and then uses this function to mangle just the part
 778    underneath the function scope.  So don't use the <local-name>
 779    production, to avoid an infinite recursion.  */
 780
 781 static void
 782 write_name (tree decl, const int ignore_local_scope)
 783 {
 784   tree context;
 785
 786   MANGLE_TRACE_TREE ("name", decl);
 787
 788   if (TREE_CODE (decl) == TYPE_DECL)
 789     {
 790       /* In case this is a typedef, fish out the corresponding
 791          TYPE_DECL for the main variant.  */
 792       decl = TYPE_NAME (TYPE_MAIN_VARIANT (TREE_TYPE (decl)));
 793     }
 794
 795   context = decl_mangling_context (decl);
 796
 797   /* A decl in :: or ::std scope is treated specially.  The former is
 798      mangled using <unscoped-name> or <unscoped-template-name>, the
 799      latter with a special substitution.  Also, a name that is
 800      directly in a local function scope is also mangled with
 801      <unscoped-name> rather than a full <nested-name>.  */
 802   if (context == NULL
 803       || context == global_namespace
 804       || DECL_NAMESPACE_STD_P (context)
 805       || (ignore_local_scope && TREE_CODE (context) == FUNCTION_DECL))
 806     {
 807       tree template_info;
 808       /* Is this a template instance?  */
 809       if (decl_is_template_id (decl, &template_info))
 810         {
 811           /* Yes: use <unscoped-template-name>.  */
 812           write_unscoped_template_name (TI_TEMPLATE (template_info));
 813           write_template_args (TI_ARGS (template_info));
 814         }
 815       else
 816         /* Everything else gets an <unqualified-name>.  */
 817         write_unscoped_name (decl);
 818     }
 819   else
 820     {
 821       /* Handle local names, unless we asked not to (that is, invoked
 822          under <local-name>, to handle only the part of the name under
 823          the local scope).  */
 824       if (!ignore_local_scope)
 825         {
 826           /* Scan up the list of scope context, looking for a
 827              function.  If we find one, this entity is in local
 828              function scope.  local_entity tracks context one scope
 829              level down, so it will contain the element that's
 830              directly in that function's scope, either decl or one of
 831              its enclosing scopes.  */
 832           tree local_entity = decl;
 833           while (context != NULL && context != global_namespace)
 834             {
 835               /* Make sure we're always dealing with decls.  */
 836               if (context != NULL && TYPE_P (context))
 837                 context = TYPE_NAME (context);
 838               /* Is this a function?  */
 839               if (TREE_CODE (context) == FUNCTION_DECL
 840                   || TREE_CODE (context) == PARM_DECL)
 841                 {
 842                   /* Yes, we have local scope.  Use the <local-name>
 843                      production for the innermost function scope.  */
 844                   write_local_name (context, local_entity, decl);
 845                   return;
 846                 }
 847               /* Up one scope level.  */
 848               local_entity = context;
 849               context = decl_mangling_context (context);
 850             }
 851
 852           /* No local scope found?  Fall through to <nested-name>.  */
 853         }
 854
 855       /* Other decls get a <nested-name> to encode their scope.  */
 856       write_nested_name (decl);
 857     }
 858 }
 859
 860 /* <unscoped-name> ::= <unqualified-name>
 861                    ::= St <unqualified-name>   # ::std::  */
 862
 863 static void
 864 write_unscoped_name (const tree decl)
 865 {
 866   tree context = decl_mangling_context (decl);
 867
 868   MANGLE_TRACE_TREE ("unscoped-name", decl);
 869
 870   /* Is DECL in ::std?  */
 871   if (DECL_NAMESPACE_STD_P (context))
 872     {
 873       write_string ("St");
 874       write_unqualified_name (decl);
 875     }
 876   else
 877     {
 878       /* If not, it should be either in the global namespace, or directly
 879          in a local function scope.  */
 880       gcc_assert (context == global_namespace
 881                   || context != NULL
 882                   || TREE_CODE (context) == FUNCTION_DECL);
 883
 884       write_unqualified_name (decl);
 885     }
 886 }
 887
 888 /* <unscoped-template-name> ::= <unscoped-name>
 889                             ::= <substitution>  */
 890
 891 static void
 892 write_unscoped_template_name (const tree decl)
 893 {
 894   MANGLE_TRACE_TREE ("unscoped-template-name", decl);
 895
 896   if (find_substitution (decl))
 897     return;
 898   write_unscoped_name (decl);
 899   add_substitution (decl);
 900 }
 901
 902 /* Write the nested name, including CV-qualifiers, of DECL.
 903
 904    <nested-name> ::= N [<CV-qualifiers>] <prefix> <unqualified-name> E
 905                  ::= N [<CV-qualifiers>] <template-prefix> <template-args> E
 906
 907    <CV-qualifiers> ::= [r] [V] [K]  */
 908
 909 static void
 910 write_nested_name (const tree decl)
 911 {
 912   tree template_info;
 913
 914   MANGLE_TRACE_TREE ("nested-name", decl);
 915
 916   write_char ('N');
 917
 918   /* Write CV-qualifiers, if this is a member function.  */
 919   if (TREE_CODE (decl) == FUNCTION_DECL
 920       && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
 921     {
 922       if (DECL_VOLATILE_MEMFUNC_P (decl))
 923         write_char ('V');
 924       if (DECL_CONST_MEMFUNC_P (decl))
 925         write_char ('K');
 926     }
 927
 928   /* Is this a template instance?  */
 929   if (decl_is_template_id (decl, &template_info))
 930     {
 931       /* Yes, use <template-prefix>.  */
 932       write_template_prefix (decl);
 933       write_template_args (TI_ARGS (template_info));
 934     }
 935   else if (TREE_CODE (TREE_TYPE (decl)) == TYPENAME_TYPE)
 936     {
 937       tree name = TYPENAME_TYPE_FULLNAME (TREE_TYPE (decl));
 938       if (TREE_CODE (name) == TEMPLATE_ID_EXPR)
 939         {
 940           write_template_prefix (decl);
 941           write_template_args (TREE_OPERAND (name, 1));
 942         }
 943       else
 944         {
 945           write_prefix (decl_mangling_context (decl));
 946           write_unqualified_name (decl);
 947         }
 948     }
 949   else
 950     {
 951       /* No, just use <prefix>  */
 952       write_prefix (decl_mangling_context (decl));
 953       write_unqualified_name (decl);
 954     }
 955   write_char ('E');
 956 }
 957
 958 /* <prefix> ::= <prefix> <unqualified-name>
 959             ::= <template-param>
 960             ::= <template-prefix> <template-args>
 961             ::= <decltype>
 962             ::= # empty
 963             ::= <substitution>  */
 964
 965 static void
 966 write_prefix (const tree node)
 967 {
 968   tree decl;
 969   /* Non-NULL if NODE represents a template-id.  */
 970   tree template_info = NULL;
 971
 972   if (node == NULL
 973       || node == global_namespace)
 974     return;
 975
 976   MANGLE_TRACE_TREE ("prefix", node);
 977
 978   if (TREE_CODE (node) == DECLTYPE_TYPE)
 979     {
 980       write_type (node);
 981       return;
 982     }
 983
 984   if (find_substitution (node))
 985     return;
 986
 987   if (DECL_P (node))
 988     {
 989       /* If this is a function or parm decl, that means we've hit function
 990          scope, so this prefix must be for a local name.  In this
 991          case, we're under the <local-name> production, which encodes
 992          the enclosing function scope elsewhere.  So don't continue
 993          here.  */
 994       if (TREE_CODE (node) == FUNCTION_DECL
 995           || TREE_CODE (node) == PARM_DECL)
 996         return;
 997
 998       decl = node;
 999       decl_is_template_id (decl, &template_info);
1000     }
1001   else
1002     {
1003       /* Node is a type.  */
1004       decl = TYPE_NAME (node);
1005       if (CLASSTYPE_TEMPLATE_ID_P (node))
1006         template_info = TYPE_TEMPLATE_INFO (node);
1007     }
1008
1009   /* In G++ 3.2, the name of the template parameter was used.  */
1010   if (TREE_CODE (node) == TEMPLATE_TYPE_PARM
1011       && !abi_version_at_least (2))
1012     G.need_abi_warning = true;
1013
1014   if (TREE_CODE (node) == TEMPLATE_TYPE_PARM
1015       && abi_version_at_least (2))
1016     write_template_param (node);
1017   else if (template_info != NULL)
1018     /* Templated.  */
1019     {
1020       write_template_prefix (decl);
1021       write_template_args (TI_ARGS (template_info));
1022     }
1023   else if (TREE_CODE (TREE_TYPE (decl)) == TYPENAME_TYPE)
1024     {
1025       tree name = TYPENAME_TYPE_FULLNAME (TREE_TYPE (decl));
1026       if (TREE_CODE (name) == TEMPLATE_ID_EXPR)
1027         {
1028           write_template_prefix (decl);
1029           write_template_args (TREE_OPERAND (name, 1));
1030         }
1031       else
1032         {
1033           write_prefix (decl_mangling_context (decl));
1034           write_unqualified_name (decl);
1035         }
1036     }
1037   else
1038     /* Not templated.  */
1039     {
1040       write_prefix (decl_mangling_context (decl));
1041       write_unqualified_name (decl);
1042       if (TREE_CODE (decl) == VAR_DECL
1043           || TREE_CODE (decl) == FIELD_DECL)
1044         {
1045           /* <data-member-prefix> := <member source-name> M */
1046           write_char ('M');
1047           return;
1048         }
1049     }
1050
1051   add_substitution (node);
1052 }
1053
1054 /* <template-prefix> ::= <prefix> <template component>
1055                      ::= <template-param>
1056                      ::= <substitution>  */
1057
1058 static void
1059 write_template_prefix (const tree node)
1060 {
1061   tree decl = DECL_P (node) ? node : TYPE_NAME (node);
1062   tree type = DECL_P (node) ? TREE_TYPE (node) : node;
1063   tree context = decl_mangling_context (decl);
1064   tree template_info;
1065   tree templ;
1066   tree substitution;
1067
1068   MANGLE_TRACE_TREE ("template-prefix", node);
1069
1070   /* Find the template decl.  */
1071   if (decl_is_template_id (decl, &template_info))
1072     templ = TI_TEMPLATE (template_info);
1073   else if (TREE_CODE (type) == TYPENAME_TYPE)
1074     /* For a typename type, all we have is the name.  */
1075     templ = DECL_NAME (decl);
1076   else
1077     {
1078       gcc_assert (CLASSTYPE_TEMPLATE_ID_P (type));
1079
1080       templ = TYPE_TI_TEMPLATE (type);
1081     }
1082
1083   /* For a member template, though, the template name for the
1084      innermost name must have all the outer template levels
1085      instantiated.  For instance, consider
1086
1087        template<typename T> struct Outer {
1088          template<typename U> struct Inner {};
1089        };
1090
1091      The template name for `Inner' in `Outer<int>::Inner<float>' is
1092      `Outer<int>::Inner<U>'.  In g++, we don't instantiate the template
1093      levels separately, so there's no TEMPLATE_DECL available for this
1094      (there's only `Outer<T>::Inner<U>').
1095
1096      In order to get the substitutions right, we create a special
1097      TREE_LIST to represent the substitution candidate for a nested
1098      template.  The TREE_PURPOSE is the template's context, fully
1099      instantiated, and the TREE_VALUE is the TEMPLATE_DECL for the inner
1100      template.
1101
1102      So, for the example above, `Outer<int>::Inner' is represented as a
1103      substitution candidate by a TREE_LIST whose purpose is `Outer<int>'
1104      and whose value is `Outer<T>::Inner<U>'.  */
1105   if (TYPE_P (context))
1106     substitution = build_tree_list (context, templ);
1107   else
1108     substitution = templ;
1109
1110   if (find_substitution (substitution))
1111     return;
1112
1113   /* In G++ 3.2, the name of the template template parameter was used.  */
1114   if (TREE_TYPE (templ)
1115       && TREE_CODE (TREE_TYPE (templ)) == TEMPLATE_TEMPLATE_PARM
1116       && !abi_version_at_least (2))
1117     G.need_abi_warning = true;
1118
1119   if (TREE_TYPE (templ)
1120       && TREE_CODE (TREE_TYPE (templ)) == TEMPLATE_TEMPLATE_PARM
1121       && abi_version_at_least (2))
1122     write_template_param (TREE_TYPE (templ));
1123   else
1124     {
1125       write_prefix (context);
1126       write_unqualified_name (decl);
1127     }
1128
1129   add_substitution (substitution);
1130 }
1131
1132 /* We don't need to handle thunks, vtables, or VTTs here.  Those are
1133    mangled through special entry points.
1134
1135     <unqualified-name>  ::= <operator-name>
1136                         ::= <special-name>
1137                         ::= <source-name>
1138                         ::= <unnamed-type-name>
1139                         ::= <local-source-name>
1140
1141     <local-source-name> ::= L <source-name> <discriminator> */
1142
1143 static void
1144 write_unqualified_id (tree identifier)
1145 {
1146   if (IDENTIFIER_TYPENAME_P (identifier))
1147     write_conversion_operator_name (TREE_TYPE (identifier));
1148   else if (IDENTIFIER_OPNAME_P (identifier))
1149     {
1150       int i;
1151       const char *mangled_name = NULL;
1152
1153       /* Unfortunately, there is no easy way to go from the
1154          name of the operator back to the corresponding tree
1155          code.  */
1156       for (i = 0; i < MAX_TREE_CODES; ++i)
1157         if (operator_name_info[i].identifier == identifier)
1158           {
1159             /* The ABI says that we prefer binary operator
1160                names to unary operator names.  */
1161             if (operator_name_info[i].arity == 2)
1162               {
1163                 mangled_name = operator_name_info[i].mangled_name;
1164                 break;
1165               }
1166             else if (!mangled_name)
1167               mangled_name = operator_name_info[i].mangled_name;
1168           }
1169         else if (assignment_operator_name_info[i].identifier
1170                  == identifier)
1171           {
1172             mangled_name
1173               = assignment_operator_name_info[i].mangled_name;
1174             break;
1175           }
1176       write_string (mangled_name);
1177     }
1178   else if (UDLIT_OPER_P (identifier))
1179     write_literal_operator_name (identifier);
1180   else
1181     write_source_name (identifier);
1182 }
1183
1184 static void
1185 write_unqualified_name (const tree decl)
1186 {
1187   MANGLE_TRACE_TREE ("unqualified-name", decl);
1188
1189   if (TREE_CODE (decl) == IDENTIFIER_NODE)
1190     {
1191       write_unqualified_id (decl);
1192       return;
1193     }
1194
1195   bool found = false;
1196
1197   if (DECL_NAME (decl) == NULL_TREE)
1198     {
1199       found = true;
1200       gcc_assert (DECL_ASSEMBLER_NAME_SET_P (decl));
1201       write_source_name (DECL_ASSEMBLER_NAME (decl));
1202     }
1203   else if (DECL_DECLARES_FUNCTION_P (decl))
1204     {
1205       found = true;
1206       if (DECL_CONSTRUCTOR_P (decl))
1207         write_special_name_constructor (decl);
1208       else if (DECL_DESTRUCTOR_P (decl))
1209         write_special_name_destructor (decl);
1210       else if (DECL_CONV_FN_P (decl))
1211         {
1212           /* Conversion operator. Handle it right here.
1213              <operator> ::= cv <type>  */
1214           tree type;
1215           if (decl_is_template_id (decl, NULL))
1216             {
1217               tree fn_type;
1218               fn_type = get_mostly_instantiated_function_type (decl);
1219               type = TREE_TYPE (fn_type);
1220             }
1221           else
1222             type = DECL_CONV_FN_TYPE (decl);
1223           write_conversion_operator_name (type);
1224         }
1225       else if (DECL_OVERLOADED_OPERATOR_P (decl))
1226         {
1227           operator_name_info_t *oni;
1228           if (DECL_ASSIGNMENT_OPERATOR_P (decl))
1229             oni = assignment_operator_name_info;
1230           else
1231             oni = operator_name_info;
1232
1233           write_string (oni[DECL_OVERLOADED_OPERATOR_P (decl)].mangled_name);
1234         }
1235       else if (UDLIT_OPER_P (DECL_NAME (decl)))
1236         write_literal_operator_name (DECL_NAME (decl));
1237       else
1238         found = false;
1239     }
1240
1241   if (found)
1242     /* OK */;
1243   else if (VAR_OR_FUNCTION_DECL_P (decl) && ! TREE_PUBLIC (decl)
1244            && DECL_NAMESPACE_SCOPE_P (decl)
1245            && decl_linkage (decl) == lk_internal)
1246     {
1247       MANGLE_TRACE_TREE ("local-source-name", decl);
1248       write_char ('L');
1249       write_source_name (DECL_NAME (decl));
1250       /* The default discriminator is 1, and that's all we ever use,
1251          so there's no code to output one here.  */
1252     }
1253   else
1254     {
1255       tree type = TREE_TYPE (decl);
1256
1257       if (TREE_CODE (decl) == TYPE_DECL
1258           && TYPE_ANONYMOUS_P (type))
1259         write_unnamed_type_name (type);
1260       else if (TREE_CODE (decl) == TYPE_DECL
1261                && LAMBDA_TYPE_P (type))
1262         write_closure_type_name (type);
1263       else
1264         write_source_name (DECL_NAME (decl));
1265     }
1266
1267   tree attrs = (TREE_CODE (decl) == TYPE_DECL
1268                 ? TYPE_ATTRIBUTES (TREE_TYPE (decl))
1269                 : DECL_ATTRIBUTES (decl));
1270   write_abi_tags (lookup_attribute ("abi_tag", attrs));
1271 }
1272
1273 /* Write the unqualified-name for a conversion operator to TYPE.  */
1274
1275 static void
1276 write_conversion_operator_name (const tree type)
1277 {
1278   write_string ("cv");
1279   write_type (type);
1280 }
1281
1282 /* Non-terminal <source-name>.  IDENTIFIER is an IDENTIFIER_NODE.
1283
1284      <source-name> ::= </length/ number> <identifier>  */
1285
1286 static void
1287 write_source_name (tree identifier)
1288 {
1289   MANGLE_TRACE_TREE ("source-name", identifier);
1290
1291   /* Never write the whole template-id name including the template
1292      arguments; we only want the template name.  */
1293   if (IDENTIFIER_TEMPLATE (identifier))
1294     identifier = IDENTIFIER_TEMPLATE (identifier);
1295
1296   write_unsigned_number (IDENTIFIER_LENGTH (identifier));
1297   write_identifier (IDENTIFIER_POINTER (identifier));
1298 }
1299
1300 /* Compare two TREE_STRINGs like strcmp.  */
1301
1302 int
1303 tree_string_cmp (const void *p1, const void *p2)
1304 {
1305   if (p1 == p2)
1306     return 0;
1307   tree s1 = *(const tree*)p1;
1308   tree s2 = *(const tree*)p2;
1309   return strcmp (TREE_STRING_POINTER (s1),
1310                  TREE_STRING_POINTER (s2));
1311 }
1312
1313 /* ID is the name of a function or type with abi_tags attribute TAGS.
1314    Write out the name, suitably decorated.  */
1315
1316 static void
1317 write_abi_tags (tree tags)
1318 {
1319   if (tags == NULL_TREE)
1320     return;
1321
1322   tags = TREE_VALUE (tags);
1323
1324   vec<tree, va_gc> * vec = make_tree_vector();
1325
1326   for (tree t = tags; t; t = TREE_CHAIN (t))
1327     {
1328       tree str = TREE_VALUE (t);
1329       vec_safe_push (vec, str);
1330     }
1331
1332   vec->qsort (tree_string_cmp);
1333
1334   unsigned i; tree str;
1335   FOR_EACH_VEC_ELT (*vec, i, str)
1336     {
1337       write_string ("B");
1338       write_unsigned_number (TREE_STRING_LENGTH (str) - 1);
1339       write_identifier (TREE_STRING_POINTER (str));
1340     }
1341
1342   release_tree_vector (vec);
1343 }
1344
1345 /* Write a user-defined literal operator.
1346           ::= li <source-name>    # "" <source-name>
1347    IDENTIFIER is an LITERAL_IDENTIFIER_NODE.  */
1348
1349 static void
1350 write_literal_operator_name (tree identifier)
1351 {
1352   const char* suffix = UDLIT_OP_SUFFIX (identifier);
1353   write_identifier (UDLIT_OP_MANGLED_PREFIX);
1354   write_unsigned_number (strlen (suffix));
1355   write_identifier (suffix);
1356 }
1357
1358 /* Encode 0 as _, and 1+ as n-1_.  */
1359
1360 static void
1361 write_compact_number (int num)
1362 {
1363   if (num > 0)
1364     write_unsigned_number (num - 1);
1365   write_char ('_');
1366 }
1367
1368 /* Return how many unnamed types precede TYPE in its enclosing class.  */
1369
1370 static int
1371 nested_anon_class_index (tree type)
1372 {
1373   int index = 0;
1374   tree member = TYPE_FIELDS (TYPE_CONTEXT (type));
1375   for (; member; member = DECL_CHAIN (member))
1376     if (DECL_IMPLICIT_TYPEDEF_P (member))
1377       {
1378         tree memtype = TREE_TYPE (member);
1379         if (memtype == type)
1380           return index;
1381         else if (TYPE_ANONYMOUS_P (memtype))
1382           ++index;
1383       }
1384
1385   gcc_unreachable ();
1386 }
1387
1388 /* <unnamed-type-name> ::= Ut [ <nonnegative number> ] _ */
1389
1390 static void
1391 write_unnamed_type_name (const tree type)
1392 {
1393   int discriminator;
1394   MANGLE_TRACE_TREE ("unnamed-type-name", type);
1395
1396   if (TYPE_FUNCTION_SCOPE_P (type))
1397     discriminator = local_class_index (type);
1398   else if (TYPE_CLASS_SCOPE_P (type))
1399     discriminator = nested_anon_class_index (type);
1400   else
1401     {
1402       gcc_assert (no_linkage_check (type, /*relaxed_p=*/true));
1403       /* Just use the old mangling at namespace scope.  */
1404       write_source_name (TYPE_IDENTIFIER (type));
1405       return;
1406     }
1407
1408   write_string ("Ut");
1409   write_compact_number (discriminator);
1410 }
1411
1412 /* <closure-type-name> ::= Ul <lambda-sig> E [ <nonnegative number> ] _
1413    <lambda-sig> ::= <parameter type>+  # Parameter types or "v" if the lambda has no parameters */
1414
1415 static void
1416 write_closure_type_name (const tree type)
1417 {
1418   tree fn = lambda_function (type);
1419   tree lambda = CLASSTYPE_LAMBDA_EXPR (type);
1420   tree parms = TYPE_ARG_TYPES (TREE_TYPE (fn));
1421
1422   MANGLE_TRACE_TREE ("closure-type-name", type);
1423
1424   write_string ("Ul");
1425   write_method_parms (parms, /*method_p=*/1, fn);
1426   write_char ('E');
1427   write_compact_number (LAMBDA_EXPR_DISCRIMINATOR (lambda));
1428 }
1429
1430 /* Convert NUMBER to ascii using base BASE and generating at least
1431    MIN_DIGITS characters. BUFFER points to the _end_ of the buffer
1432    into which to store the characters. Returns the number of
1433    characters generated (these will be layed out in advance of where
1434    BUFFER points).  */
1435
1436 static int
1437 hwint_to_ascii (unsigned HOST_WIDE_INT number, const unsigned int base,
1438                 char *buffer, const unsigned int min_digits)
1439 {
1440   static const char base_digits[] = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ";
1441   unsigned digits = 0;
1442
1443   while (number)
1444     {
1445       unsigned HOST_WIDE_INT d = number / base;
1446
1447       *--buffer = base_digits[number - d * base];
1448       digits++;
1449       number = d;
1450     }
1451   while (digits < min_digits)
1452     {
1453       *--buffer = base_digits[0];
1454       digits++;
1455     }
1456   return digits;
1457 }
1458
1459 /* Non-terminal <number>.
1460
1461      <number> ::= [n] </decimal integer/>  */
1462
1463 static void
1464 write_number (unsigned HOST_WIDE_INT number, const int unsigned_p,
1465               const unsigned int base)
1466 {
1467   char buffer[sizeof (HOST_WIDE_INT) * 8];
1468   unsigned count = 0;
1469
1470   if (!unsigned_p && (HOST_WIDE_INT) number < 0)
1471     {
1472       write_char ('n');
1473       number = -((HOST_WIDE_INT) number);
1474     }
1475   count = hwint_to_ascii (number, base, buffer + sizeof (buffer), 1);
1476   write_chars (buffer + sizeof (buffer) - count, count);
1477 }
1478
1479 /* Write out an integral CST in decimal. Most numbers are small, and
1480    representable in a HOST_WIDE_INT. Occasionally we'll have numbers
1481    bigger than that, which we must deal with.  */
1482
1483 static inline void
1484 write_integer_cst (const tree cst)
1485 {
1486   int sign = tree_int_cst_sgn (cst);
1487
1488   if (TREE_INT_CST_HIGH (cst) + (sign < 0))
1489     {
1490       /* A bignum. We do this in chunks, each of which fits in a
1491          HOST_WIDE_INT.  */
1492       char buffer[sizeof (HOST_WIDE_INT) * 8 * 2];
1493       unsigned HOST_WIDE_INT chunk;
1494       unsigned chunk_digits;
1495       char *ptr = buffer + sizeof (buffer);
1496       unsigned count = 0;
1497       tree n, base, type;
1498       int done;
1499
1500       /* HOST_WIDE_INT must be at least 32 bits, so 10^9 is
1501          representable.  */
1502       chunk = 1000000000;
1503       chunk_digits = 9;
1504
1505       if (sizeof (HOST_WIDE_INT) >= 8)
1506         {
1507           /* It is at least 64 bits, so 10^18 is representable.  */
1508           chunk_digits = 18;
1509           chunk *= chunk;
1510         }
1511
1512       type = c_common_signed_or_unsigned_type (1, TREE_TYPE (cst));
1513       base = build_int_cstu (type, chunk);
1514       n = build_int_cst_wide (type,
1515                               TREE_INT_CST_LOW (cst), TREE_INT_CST_HIGH (cst));
1516
1517       if (sign < 0)
1518         {
1519           write_char ('n');
1520           n = fold_build1_loc (input_location, NEGATE_EXPR, type, n);
1521         }
1522       do
1523         {
1524           tree d = fold_build2_loc (input_location, FLOOR_DIV_EXPR, type, n, base);
1525           tree tmp = fold_build2_loc (input_location, MULT_EXPR, type, d, base);
1526           unsigned c;
1527
1528           done = integer_zerop (d);
1529           tmp = fold_build2_loc (input_location, MINUS_EXPR, type, n, tmp);
1530           c = hwint_to_ascii (TREE_INT_CST_LOW (tmp), 10, ptr,
1531                               done ? 1 : chunk_digits);
1532           ptr -= c;
1533           count += c;
1534           n = d;
1535         }
1536       while (!done);
1537       write_chars (ptr, count);
1538     }
1539   else
1540     {
1541       /* A small num.  */
1542       unsigned HOST_WIDE_INT low = TREE_INT_CST_LOW (cst);
1543
1544       if (sign < 0)
1545         {
1546           write_char ('n');
1547           low = -low;
1548         }
1549       write_unsigned_number (low);
1550     }
1551 }
1552
1553 /* Write out a floating-point literal.
1554
1555     "Floating-point literals are encoded using the bit pattern of the
1556     target processor's internal representation of that number, as a
1557     fixed-length lowercase hexadecimal string, high-order bytes first
1558     (even if the target processor would store low-order bytes first).
1559     The "n" prefix is not used for floating-point literals; the sign
1560     bit is encoded with the rest of the number.
1561
1562     Here are some examples, assuming the IEEE standard representation
1563     for floating point numbers.  (Spaces are for readability, not
1564     part of the encoding.)
1565
1566         1.0f                    Lf 3f80 0000 E
1567        -1.0f                    Lf bf80 0000 E
1568         1.17549435e-38f         Lf 0080 0000 E
1569         1.40129846e-45f         Lf 0000 0001 E
1570         0.0f                    Lf 0000 0000 E"
1571
1572    Caller is responsible for the Lx and the E.  */
1573 static void
1574 write_real_cst (const tree value)
1575 {
1576   if (abi_version_at_least (2))
1577     {
1578       long target_real[4];  /* largest supported float */
1579       char buffer[9];       /* eight hex digits in a 32-bit number */
1580       int i, limit, dir;
1581
1582       tree type = TREE_TYPE (value);
1583       int words = GET_MODE_BITSIZE (TYPE_MODE (type)) / 32;
1584
1585       real_to_target (target_real, &TREE_REAL_CST (value),
1586                       TYPE_MODE (type));
1587
1588       /* The value in target_real is in the target word order,
1589          so we must write it out backward if that happens to be
1590          little-endian.  write_number cannot be used, it will
1591          produce uppercase.  */
1592       if (FLOAT_WORDS_BIG_ENDIAN)
1593         i = 0, limit = words, dir = 1;
1594       else
1595         i = words - 1, limit = -1, dir = -1;
1596
1597       for (; i != limit; i += dir)
1598         {
1599           sprintf (buffer, "%08lx", (unsigned long) target_real[i]);
1600           write_chars (buffer, 8);
1601         }
1602     }
1603   else
1604     {
1605       /* In G++ 3.3 and before the REAL_VALUE_TYPE was written out
1606          literally.  Note that compatibility with 3.2 is impossible,
1607          because the old floating-point emulator used a different
1608          format for REAL_VALUE_TYPE.  */
1609       size_t i;
1610       for (i = 0; i < sizeof (TREE_REAL_CST (value)); ++i)
1611         write_number (((unsigned char *) &TREE_REAL_CST (value))[i],
1612                       /*unsigned_p*/ 1,
1613                       /*base*/ 16);
1614       G.need_abi_warning = 1;
1615     }
1616 }
1617
1618 /* Non-terminal <identifier>.
1619
1620      <identifier> ::= </unqualified source code identifier>  */
1621
1622 static void
1623 write_identifier (const char *identifier)
1624 {
1625   MANGLE_TRACE ("identifier", identifier);
1626   write_string (identifier);
1627 }
1628
1629 /* Handle constructor productions of non-terminal <special-name>.
1630    CTOR is a constructor FUNCTION_DECL.
1631
1632      <special-name> ::= C1   # complete object constructor
1633                     ::= C2   # base object constructor
1634                     ::= C3   # complete object allocating constructor
1635
1636    Currently, allocating constructors are never used.
1637
1638    We also need to provide mangled names for the maybe-in-charge
1639    constructor, so we treat it here too.  mangle_decl_string will
1640    append *INTERNAL* to that, to make sure we never emit it.  */
1641
1642 static void
1643 write_special_name_constructor (const tree ctor)
1644 {
1645   if (DECL_BASE_CONSTRUCTOR_P (ctor))
1646     write_string ("C2");
1647   else
1648     {
1649       gcc_assert (DECL_COMPLETE_CONSTRUCTOR_P (ctor)
1650                   /* Even though we don't ever emit a definition of
1651                      the old-style destructor, we still have to
1652                      consider entities (like static variables) nested
1653                      inside it.  */
1654                   || DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (ctor));
1655       write_string ("C1");
1656     }
1657 }
1658
1659 /* Handle destructor productions of non-terminal <special-name>.
1660    DTOR is a destructor FUNCTION_DECL.
1661
1662      <special-name> ::= D0 # deleting (in-charge) destructor
1663                     ::= D1 # complete object (in-charge) destructor
1664                     ::= D2 # base object (not-in-charge) destructor
1665
1666    We also need to provide mangled names for the maybe-incharge
1667    destructor, so we treat it here too.  mangle_decl_string will
1668    append *INTERNAL* to that, to make sure we never emit it.  */
1669
1670 static void
1671 write_special_name_destructor (const tree dtor)
1672 {
1673   if (DECL_DELETING_DESTRUCTOR_P (dtor))
1674     write_string ("D0");
1675   else if (DECL_BASE_DESTRUCTOR_P (dtor))
1676     write_string ("D2");
1677   else
1678     {
1679       gcc_assert (DECL_COMPLETE_DESTRUCTOR_P (dtor)
1680                   /* Even though we don't ever emit a definition of
1681                      the old-style destructor, we still have to
1682                      consider entities (like static variables) nested
1683                      inside it.  */
1684                   || DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (dtor));
1685       write_string ("D1");
1686     }
1687 }
1688
1689 /* Scan the vector of local classes and return how many others with the
1690    same name (or same no name) and context precede ENTITY.  */
1691
1692 static int
1693 local_class_index (tree entity)
1694 {
1695   int ix, discriminator = 0;
1696   tree name = (TYPE_ANONYMOUS_P (entity) ? NULL_TREE
1697                : TYPE_IDENTIFIER (entity));
1698   tree ctx = TYPE_CONTEXT (entity);
1699   for (ix = 0; ; ix++)
1700     {
1701       tree type = (*local_classes)[ix];
1702       if (type == entity)
1703         return discriminator;
1704       if (TYPE_CONTEXT (type) == ctx
1705           && (name ? TYPE_IDENTIFIER (type) == name
1706               : TYPE_ANONYMOUS_P (type)))
1707         ++discriminator;
1708     }
1709   gcc_unreachable ();
1710 }
1711
1712 /* Return the discriminator for ENTITY appearing inside
1713    FUNCTION.  The discriminator is the lexical ordinal of VAR among
1714    entities with the same name in the same FUNCTION.  */
1715
1716 static int
1717 discriminator_for_local_entity (tree entity)
1718 {
1719   if (DECL_DISCRIMINATOR_P (entity))
1720     {
1721       if (DECL_DISCRIMINATOR_SET_P (entity))
1722         return DECL_DISCRIMINATOR (entity);
1723       else
1724         /* The first entity with a particular name doesn't get
1725            DECL_DISCRIMINATOR set up.  */
1726         return 0;
1727     }
1728   else if (TREE_CODE (entity) == TYPE_DECL)
1729     {
1730       /* Scan the list of local classes.  */
1731       entity = TREE_TYPE (entity);
1732
1733       /* Lambdas and unnamed types have their own discriminators.  */
1734       if (LAMBDA_TYPE_P (entity) || TYPE_ANONYMOUS_P (entity))
1735         return 0;
1736
1737       return local_class_index (entity);
1738     }
1739   else
1740     gcc_unreachable ();
1741 }
1742
1743 /* Return the discriminator for STRING, a string literal used inside
1744    FUNCTION.  The discriminator is the lexical ordinal of STRING among
1745    string literals used in FUNCTION.  */
1746
1747 static int
1748 discriminator_for_string_literal (tree /*function*/,
1749                                   tree /*string*/)
1750 {
1751   /* For now, we don't discriminate amongst string literals.  */
1752   return 0;
1753 }
1754
1755 /*   <discriminator> := _ <number>
1756
1757    The discriminator is used only for the second and later occurrences
1758    of the same name within a single function. In this case <number> is
1759    n - 2, if this is the nth occurrence, in lexical order.  */
1760
1761 static void
1762 write_discriminator (const int discriminator)
1763 {
1764   /* If discriminator is zero, don't write anything.  Otherwise...  */
1765   if (discriminator > 0)
1766     {
1767       write_char ('_');
1768       write_unsigned_number (discriminator - 1);
1769     }
1770 }
1771
1772 /* Mangle the name of a function-scope entity.  FUNCTION is the
1773    FUNCTION_DECL for the enclosing function, or a PARM_DECL for lambdas in
1774    default argument scope.  ENTITY is the decl for the entity itself.
1775    LOCAL_ENTITY is the entity that's directly scoped in FUNCTION_DECL,
1776    either ENTITY itself or an enclosing scope of ENTITY.
1777
1778      <local-name> := Z <function encoding> E <entity name> [<discriminator>]
1779                   := Z <function encoding> E s [<discriminator>]
1780                   := Z <function encoding> Ed [ <parameter number> ] _ <entity name> */
1781
1782 static void
1783 write_local_name (tree function, const tree local_entity,
1784                   const tree entity)
1785 {
1786   tree parm = NULL_TREE;
1787
1788   MANGLE_TRACE_TREE ("local-name", entity);
1789
1790   if (TREE_CODE (function) == PARM_DECL)
1791     {
1792       parm = function;
1793       function = DECL_CONTEXT (parm);
1794     }
1795
1796   write_char ('Z');
1797   write_encoding (function);
1798   write_char ('E');
1799
1800   /* For this purpose, parameters are numbered from right-to-left.  */
1801   if (parm)
1802     {
1803       tree t;
1804       int i = 0;
1805       for (t = DECL_ARGUMENTS (function); t; t = DECL_CHAIN (t))
1806         {
1807           if (t == parm)
1808             i = 1;
1809           else if (i)
1810             ++i;
1811         }
1812       write_char ('d');
1813       write_compact_number (i - 1);
1814     }
1815
1816   if (TREE_CODE (entity) == STRING_CST)
1817     {
1818       write_char ('s');
1819       write_discriminator (discriminator_for_string_literal (function,
1820                                                              entity));
1821     }
1822   else
1823     {
1824       /* Now the <entity name>.  Let write_name know its being called
1825          from <local-name>, so it doesn't try to process the enclosing
1826          function scope again.  */
1827       write_name (entity, /*ignore_local_scope=*/1);
1828       write_discriminator (discriminator_for_local_entity (local_entity));
1829     }
1830 }
1831
1832 /* Non-terminals <type> and <CV-qualifier>.
1833
1834      <type> ::= <builtin-type>
1835             ::= <function-type>
1836             ::= <class-enum-type>
1837             ::= <array-type>
1838             ::= <pointer-to-member-type>
1839             ::= <template-param>
1840             ::= <substitution>
1841             ::= <CV-qualifier>
1842             ::= P <type>    # pointer-to
1843             ::= R <type>    # reference-to
1844             ::= C <type>    # complex pair (C 2000)
1845             ::= G <type>    # imaginary (C 2000)     [not supported]
1846             ::= U <source-name> <type>   # vendor extended type qualifier
1847
1848    C++0x extensions
1849
1850      <type> ::= RR <type>   # rvalue reference-to
1851      <type> ::= Dt <expression> # decltype of an id-expression or
1852                                 # class member access
1853      <type> ::= DT <expression> # decltype of an expression
1854      <type> ::= Dn              # decltype of nullptr
1855
1856    TYPE is a type node.  */
1857
1858 static void
1859 write_type (tree type)
1860 {
1861   /* This gets set to nonzero if TYPE turns out to be a (possibly
1862      CV-qualified) builtin type.  */
1863   int is_builtin_type = 0;
1864
1865   MANGLE_TRACE_TREE ("type", type);
1866
1867   if (type == error_mark_node)
1868     return;
1869
1870   type = canonicalize_for_substitution (type);
1871   if (find_substitution (type))
1872     return;
1873
1874
1875   if (write_CV_qualifiers_for_type (type) > 0)
1876     /* If TYPE was CV-qualified, we just wrote the qualifiers; now
1877        mangle the unqualified type.  The recursive call is needed here
1878        since both the qualified and unqualified types are substitution
1879        candidates.  */
1880     write_type (TYPE_MAIN_VARIANT (type));
1881   else if (TREE_CODE (type) == ARRAY_TYPE)
1882     /* It is important not to use the TYPE_MAIN_VARIANT of TYPE here
1883        so that the cv-qualification of the element type is available
1884        in write_array_type.  */
1885     write_array_type (type);
1886   else
1887     {
1888       tree type_orig = type;
1889
1890       /* See through any typedefs.  */
1891       type = TYPE_MAIN_VARIANT (type);
1892
1893       /* According to the C++ ABI, some library classes are passed the
1894          same as the scalar type of their single member and use the same
1895          mangling.  */
1896       if (TREE_CODE (type) == RECORD_TYPE && TYPE_TRANSPARENT_AGGR (type))
1897         type = TREE_TYPE (first_field (type));
1898
1899       if (TYPE_PTRDATAMEM_P (type))
1900         write_pointer_to_member_type (type);
1901       else
1902         {
1903           /* Handle any target-specific fundamental types.  */
1904           const char *target_mangling
1905             = targetm.mangle_type (type_orig);
1906
1907           if (target_mangling)
1908             {
1909               write_string (target_mangling);
1910               /* Add substitutions for types other than fundamental
1911                  types.  */
1912               if (TREE_CODE (type) != VOID_TYPE
1913                   && TREE_CODE (type) != INTEGER_TYPE
1914                   && TREE_CODE (type) != REAL_TYPE
1915                   && TREE_CODE (type) != BOOLEAN_TYPE)
1916                 add_substitution (type);
1917               return;
1918             }
1919
1920           switch (TREE_CODE (type))
1921             {
1922             case VOID_TYPE:
1923             case BOOLEAN_TYPE:
1924             case INTEGER_TYPE:  /* Includes wchar_t.  */
1925             case REAL_TYPE:
1926             case FIXED_POINT_TYPE:
1927               {
1928                 /* If this is a typedef, TYPE may not be one of
1929                    the standard builtin type nodes, but an alias of one.  Use
1930                    TYPE_MAIN_VARIANT to get to the underlying builtin type.  */
1931                 write_builtin_type (TYPE_MAIN_VARIANT (type));
1932                 ++is_builtin_type;
1933               }
1934               break;
1935
1936             case COMPLEX_TYPE:
1937               write_char ('C');
1938               write_type (TREE_TYPE (type));
1939               break;
1940
1941             case FUNCTION_TYPE:
1942             case METHOD_TYPE:
1943               write_function_type (type);
1944               break;
1945
1946             case UNION_TYPE:
1947             case RECORD_TYPE:
1948             case ENUMERAL_TYPE:
1949               /* A pointer-to-member function is represented as a special
1950                  RECORD_TYPE, so check for this first.  */
1951               if (TYPE_PTRMEMFUNC_P (type))
1952                 write_pointer_to_member_type (type);
1953               else
1954                 write_class_enum_type (type);
1955               break;
1956
1957             case TYPENAME_TYPE:
1958             case UNBOUND_CLASS_TEMPLATE:
1959               /* We handle TYPENAME_TYPEs and UNBOUND_CLASS_TEMPLATEs like
1960                  ordinary nested names.  */
1961               write_nested_name (TYPE_STUB_DECL (type));
1962               break;
1963
1964             case POINTER_TYPE:
1965             case REFERENCE_TYPE:
1966               if (TREE_CODE (type) == POINTER_TYPE)
1967                 write_char ('P');
1968               else if (TYPE_REF_IS_RVALUE (type))
1969                 write_char ('O');
1970               else
1971                 write_char ('R');
1972               {
1973                 tree target = TREE_TYPE (type);
1974                 /* Attribute const/noreturn are not reflected in mangling.
1975                    We strip them here rather than at a lower level because
1976                    a typedef or template argument can have function type
1977                    with function-cv-quals (that use the same representation),
1978                    but you can't have a pointer/reference to such a type.  */
1979                 if (abi_version_at_least (5)
1980                     && TREE_CODE (target) == FUNCTION_TYPE)
1981                   target = build_qualified_type (target, TYPE_UNQUALIFIED);
1982                 write_type (target);
1983               }
1984               break;
1985
1986             case TEMPLATE_TYPE_PARM:
1987               if (is_auto (type))
1988                 {
1989                   write_identifier ("Da");
1990                   ++is_builtin_type;
1991                   break;
1992                 }
1993               /* else fall through.  */
1994             case TEMPLATE_PARM_INDEX:
1995               write_template_param (type);
1996               break;
1997
1998             case TEMPLATE_TEMPLATE_PARM:
1999               write_template_template_param (type);
2000               break;
2001
2002             case BOUND_TEMPLATE_TEMPLATE_PARM:
2003               write_template_template_param (type);
2004               write_template_args
2005                 (TI_ARGS (TEMPLATE_TEMPLATE_PARM_TEMPLATE_INFO (type)));
2006               break;
2007
2008             case VECTOR_TYPE:
2009               if (abi_version_at_least (4))
2010                 {
2011                   write_string ("Dv");
2012                   /* Non-constant vector size would be encoded with
2013                      _ expression, but we don't support that yet.  */
2014                   write_unsigned_number (TYPE_VECTOR_SUBPARTS (type));
2015                   write_char ('_');
2016                 }
2017               else
2018                 {
2019                   G.need_abi_warning = 1;
2020                   write_string ("U8__vector");
2021                 }
2022               write_type (TREE_TYPE (type));
2023               break;
2024
2025             case TYPE_PACK_EXPANSION:
2026               write_string ("Dp");
2027               write_type (PACK_EXPANSION_PATTERN (type));
2028               break;
2029
2030             case DECLTYPE_TYPE:
2031               /* These shouldn't make it into mangling.  */
2032               gcc_assert (!DECLTYPE_FOR_LAMBDA_CAPTURE (type)
2033                           && !DECLTYPE_FOR_LAMBDA_PROXY (type));
2034
2035               /* In ABI <5, we stripped decltype of a plain decl.  */
2036               if (!abi_version_at_least (5)
2037                   && DECLTYPE_TYPE_ID_EXPR_OR_MEMBER_ACCESS_P (type))
2038                 {
2039                   tree expr = DECLTYPE_TYPE_EXPR (type);
2040                   tree etype = NULL_TREE;
2041                   switch (TREE_CODE (expr))
2042                     {
2043                     case VAR_DECL:
2044                     case PARM_DECL:
2045                     case RESULT_DECL:
2046                     case FUNCTION_DECL:
2047                     case CONST_DECL:
2048                     case TEMPLATE_PARM_INDEX:
2049                       etype = TREE_TYPE (expr);
2050                       break;
2051
2052                     default:
2053                       break;
2054                     }
2055
2056                   if (etype && !type_uses_auto (etype))
2057                     {
2058                       G.need_abi_warning = 1;
2059                       write_type (etype);
2060                       return;
2061                     }
2062                 }
2063
2064               write_char ('D');
2065               if (DECLTYPE_TYPE_ID_EXPR_OR_MEMBER_ACCESS_P (type))
2066                 write_char ('t');
2067               else
2068                 write_char ('T');
2069               ++cp_unevaluated_operand;
2070               write_expression (DECLTYPE_TYPE_EXPR (type));
2071               --cp_unevaluated_operand;
2072               write_char ('E');
2073               break;
2074
2075             case NULLPTR_TYPE:
2076               write_string ("Dn");
2077               if (abi_version_at_least (7))
2078                 ++is_builtin_type;
2079               break;
2080
2081             case TYPEOF_TYPE:
2082               sorry ("mangling typeof, use decltype instead");
2083               break;
2084
2085             case UNDERLYING_TYPE:
2086               sorry ("mangling __underlying_type");
2087               break;
2088
2089             case LANG_TYPE:
2090               /* fall through.  */
2091
2092             default:
2093               gcc_unreachable ();
2094             }
2095         }
2096     }
2097
2098   /* Types other than builtin types are substitution candidates.  */
2099   if (!is_builtin_type)
2100     add_substitution (type);
2101 }
2102
2103 /* Non-terminal <CV-qualifiers> for type nodes.  Returns the number of
2104    CV-qualifiers written for TYPE.
2105
2106      <CV-qualifiers> ::= [r] [V] [K]  */
2107
2108 static int
2109 write_CV_qualifiers_for_type (const tree type)
2110 {
2111   int num_qualifiers = 0;
2112
2113   /* The order is specified by:
2114
2115        "In cases where multiple order-insensitive qualifiers are
2116        present, they should be ordered 'K' (closest to the base type),
2117        'V', 'r', and 'U' (farthest from the base type) ..."
2118
2119      Note that we do not use cp_type_quals below; given "const
2120      int[3]", the "const" is emitted with the "int", not with the
2121      array.  */
2122   cp_cv_quals quals = TYPE_QUALS (type);
2123
2124   if (quals & TYPE_QUAL_RESTRICT)
2125     {
2126       write_char ('r');
2127       ++num_qualifiers;
2128     }
2129   if (quals & TYPE_QUAL_VOLATILE)
2130     {
2131       write_char ('V');
2132       ++num_qualifiers;
2133     }
2134   if (quals & TYPE_QUAL_CONST)
2135     {
2136       write_char ('K');
2137       ++num_qualifiers;
2138     }
2139
2140   return num_qualifiers;
2141 }
2142
2143 /* Non-terminal <builtin-type>.
2144
2145      <builtin-type> ::= v   # void
2146                     ::= b   # bool
2147                     ::= w   # wchar_t
2148                     ::= c   # char
2149                     ::= a   # signed char
2150                     ::= h   # unsigned char
2151                     ::= s   # short
2152                     ::= t   # unsigned short
2153                     ::= i   # int
2154                     ::= j   # unsigned int
2155                     ::= l   # long
2156                     ::= m   # unsigned long
2157                     ::= x   # long long, __int64
2158                     ::= y   # unsigned long long, __int64
2159                     ::= n   # __int128
2160                     ::= o   # unsigned __int128
2161                     ::= f   # float
2162                     ::= d   # double
2163                     ::= e   # long double, __float80
2164                     ::= g   # __float128          [not supported]
2165                     ::= u <source-name>  # vendor extended type */
2166
2167 static void
2168 write_builtin_type (tree type)
2169 {
2170   if (TYPE_CANONICAL (type))
2171     type = TYPE_CANONICAL (type);
2172
2173   switch (TREE_CODE (type))
2174     {
2175     case VOID_TYPE:
2176       write_char ('v');
2177       break;
2178
2179     case BOOLEAN_TYPE:
2180       write_char ('b');
2181       break;
2182
2183     case INTEGER_TYPE:
2184       /* TYPE may still be wchar_t, char16_t, or char32_t, since that
2185          isn't in integer_type_nodes.  */
2186       if (type == wchar_type_node)
2187         write_char ('w');
2188       else if (type == char16_type_node)
2189         write_string ("Ds");
2190       else if (type == char32_type_node)
2191         write_string ("Di");
2192       else if (TYPE_FOR_JAVA (type))
2193         write_java_integer_type_codes (type);
2194       else
2195         {
2196           size_t itk;
2197           /* Assume TYPE is one of the shared integer type nodes.  Find
2198              it in the array of these nodes.  */
2199         iagain:
2200           for (itk = 0; itk < itk_none; ++itk)
2201             if (integer_types[itk] != NULL_TREE
2202                 && type == integer_types[itk])
2203               {
2204                 /* Print the corresponding single-letter code.  */
2205                 write_char (integer_type_codes[itk]);
2206                 break;
2207               }
2208
2209           if (itk == itk_none)
2210             {
2211               tree t = c_common_type_for_mode (TYPE_MODE (type),
2212                                                TYPE_UNSIGNED (type));
2213               if (type != t)
2214                 {
2215                   type = t;
2216                   goto iagain;
2217                 }
2218
2219               if (TYPE_PRECISION (type) == 128)
2220                 write_char (TYPE_UNSIGNED (type) ? 'o' : 'n');
2221               else
2222                 {
2223                   /* Allow for cases where TYPE is not one of the shared
2224                      integer type nodes and write a "vendor extended builtin
2225                      type" with a name the form intN or uintN, respectively.
2226                      Situations like this can happen if you have an
2227                      __attribute__((__mode__(__SI__))) type and use exotic
2228                      switches like '-mint8' on AVR.  Of course, this is
2229                      undefined by the C++ ABI (and '-mint8' is not even
2230                      Standard C conforming), but when using such special
2231                      options you're pretty much in nowhere land anyway.  */
2232                   const char *prefix;
2233                   char prec[11];        /* up to ten digits for an unsigned */
2234
2235                   prefix = TYPE_UNSIGNED (type) ? "uint" : "int";
2236                   sprintf (prec, "%u", (unsigned) TYPE_PRECISION (type));
2237                   write_char ('u');     /* "vendor extended builtin type" */
2238                   write_unsigned_number (strlen (prefix) + strlen (prec));
2239                   write_string (prefix);
2240                   write_string (prec);
2241                 }
2242             }
2243         }
2244       break;
2245
2246     case REAL_TYPE:
2247       if (type == float_type_node
2248           || type == java_float_type_node)
2249         write_char ('f');
2250       else if (type == double_type_node
2251                || type == java_double_type_node)
2252         write_char ('d');
2253       else if (type == long_double_type_node)
2254         write_char ('e');
2255       else if (type == dfloat32_type_node)
2256         write_string ("Df");
2257       else if (type == dfloat64_type_node)
2258         write_string ("Dd");
2259       else if (type == dfloat128_type_node)
2260         write_string ("De");
2261       else
2262         gcc_unreachable ();
2263       break;
2264
2265     case FIXED_POINT_TYPE:
2266       write_string ("DF");
2267       if (GET_MODE_IBIT (TYPE_MODE (type)) > 0)
2268         write_unsigned_number (GET_MODE_IBIT (TYPE_MODE (type)));
2269       if (type == fract_type_node
2270           || type == sat_fract_type_node
2271           || type == accum_type_node
2272           || type == sat_accum_type_node)
2273         write_char ('i');
2274       else if (type == unsigned_fract_type_node
2275                || type == sat_unsigned_fract_type_node
2276                || type == unsigned_accum_type_node
2277                || type == sat_unsigned_accum_type_node)
2278         write_char ('j');
2279       else if (type == short_fract_type_node
2280                || type == sat_short_fract_type_node
2281                || type == short_accum_type_node
2282                || type == sat_short_accum_type_node)
2283         write_char ('s');
2284       else if (type == unsigned_short_fract_type_node
2285                || type == sat_unsigned_short_fract_type_node
2286                || type == unsigned_short_accum_type_node
2287                || type == sat_unsigned_short_accum_type_node)
2288         write_char ('t');
2289       else if (type == long_fract_type_node
2290                || type == sat_long_fract_type_node
2291                || type == long_accum_type_node
2292                || type == sat_long_accum_type_node)
2293         write_char ('l');
2294       else if (type == unsigned_long_fract_type_node
2295                || type == sat_unsigned_long_fract_type_node
2296                || type == unsigned_long_accum_type_node
2297                || type == sat_unsigned_long_accum_type_node)
2298         write_char ('m');
2299       else if (type == long_long_fract_type_node
2300                || type == sat_long_long_fract_type_node
2301                || type == long_long_accum_type_node
2302                || type == sat_long_long_accum_type_node)
2303         write_char ('x');
2304       else if (type == unsigned_long_long_fract_type_node
2305                || type == sat_unsigned_long_long_fract_type_node
2306                || type == unsigned_long_long_accum_type_node
2307                || type == sat_unsigned_long_long_accum_type_node)
2308         write_char ('y');
2309       else
2310         sorry ("mangling unknown fixed point type");
2311       write_unsigned_number (GET_MODE_FBIT (TYPE_MODE (type)));
2312       if (TYPE_SATURATING (type))
2313         write_char ('s');
2314       else
2315         write_char ('n');
2316       break;
2317
2318     default:
2319       gcc_unreachable ();
2320     }
2321 }
2322
2323 /* Non-terminal <function-type>.  NODE is a FUNCTION_TYPE or
2324    METHOD_TYPE.  The return type is mangled before the parameter
2325    types.
2326
2327      <function-type> ::= F [Y] <bare-function-type> E   */
2328
2329 static void
2330 write_function_type (const tree type)
2331 {
2332   MANGLE_TRACE_TREE ("function-type", type);
2333
2334   /* For a pointer to member function, the function type may have
2335      cv-qualifiers, indicating the quals for the artificial 'this'
2336      parameter.  */
2337   if (TREE_CODE (type) == METHOD_TYPE)
2338     {
2339       /* The first parameter must be a POINTER_TYPE pointing to the
2340          `this' parameter.  */
2341       tree this_type = class_of_this_parm (type);
2342       write_CV_qualifiers_for_type (this_type);
2343     }
2344
2345   write_char ('F');
2346   /* We don't track whether or not a type is `extern "C"'.  Note that
2347      you can have an `extern "C"' function that does not have
2348      `extern "C"' type, and vice versa:
2349
2350        extern "C" typedef void function_t();
2351        function_t f; // f has C++ linkage, but its type is
2352                      // `extern "C"'
2353
2354        typedef void function_t();
2355        extern "C" function_t f; // Vice versa.
2356
2357      See [dcl.link].  */
2358   write_bare_function_type (type, /*include_return_type_p=*/1,
2359                             /*decl=*/NULL);
2360   write_char ('E');
2361 }
2362
2363 /* Non-terminal <bare-function-type>.  TYPE is a FUNCTION_TYPE or
2364    METHOD_TYPE.  If INCLUDE_RETURN_TYPE is nonzero, the return value
2365    is mangled before the parameter types.  If non-NULL, DECL is
2366    FUNCTION_DECL for the function whose type is being emitted.
2367
2368    If DECL is a member of a Java type, then a literal 'J'
2369    is output and the return type is mangled as if INCLUDE_RETURN_TYPE
2370    were nonzero.
2371
2372      <bare-function-type> ::= [J]</signature/ type>+  */
2373
2374 static void
2375 write_bare_function_type (const tree type, const int include_return_type_p,
2376                           const tree decl)
2377 {
2378   int java_method_p;
2379
2380   MANGLE_TRACE_TREE ("bare-function-type", type);
2381
2382   /* Detect Java methods and emit special encoding.  */
2383   if (decl != NULL
2384       && DECL_FUNCTION_MEMBER_P (decl)
2385       && TYPE_FOR_JAVA (DECL_CONTEXT (decl))
2386       && !DECL_CONSTRUCTOR_P (decl)
2387       && !DECL_DESTRUCTOR_P (decl)
2388       && !DECL_CONV_FN_P (decl))
2389     {
2390       java_method_p = 1;
2391       write_char ('J');
2392     }
2393   else
2394     {
2395       java_method_p = 0;
2396     }
2397
2398   /* Mangle the return type, if requested.  */
2399   if (include_return_type_p || java_method_p)
2400     write_type (TREE_TYPE (type));
2401
2402   /* Now mangle the types of the arguments.  */
2403   ++G.parm_depth;
2404   write_method_parms (TYPE_ARG_TYPES (type),
2405                       TREE_CODE (type) == METHOD_TYPE,
2406                       decl);
2407   --G.parm_depth;
2408 }
2409
2410 /* Write the mangled representation of a method parameter list of
2411    types given in PARM_TYPES.  If METHOD_P is nonzero, the function is
2412    considered a non-static method, and the this parameter is omitted.
2413    If non-NULL, DECL is the FUNCTION_DECL for the function whose
2414    parameters are being emitted.  */
2415
2416 static void
2417 write_method_parms (tree parm_types, const int method_p, const tree decl)
2418 {
2419   tree first_parm_type;
2420   tree parm_decl = decl ? DECL_ARGUMENTS (decl) : NULL_TREE;
2421
2422   /* Assume this parameter type list is variable-length.  If it ends
2423      with a void type, then it's not.  */
2424   int varargs_p = 1;
2425
2426   /* If this is a member function, skip the first arg, which is the
2427      this pointer.
2428        "Member functions do not encode the type of their implicit this
2429        parameter."
2430
2431      Similarly, there's no need to mangle artificial parameters, like
2432      the VTT parameters for constructors and destructors.  */
2433   if (method_p)
2434     {
2435       parm_types = TREE_CHAIN (parm_types);
2436       parm_decl = parm_decl ? DECL_CHAIN (parm_decl) : NULL_TREE;
2437
2438       while (parm_decl && DECL_ARTIFICIAL (parm_decl))
2439         {
2440           parm_types = TREE_CHAIN (parm_types);
2441           parm_decl = DECL_CHAIN (parm_decl);
2442         }
2443     }
2444
2445   for (first_parm_type = parm_types;
2446        parm_types;
2447        parm_types = TREE_CHAIN (parm_types))
2448     {
2449       tree parm = TREE_VALUE (parm_types);
2450       if (parm == void_type_node)
2451         {
2452           /* "Empty parameter lists, whether declared as () or
2453              conventionally as (void), are encoded with a void parameter
2454              (v)."  */
2455           if (parm_types == first_parm_type)
2456             write_type (parm);
2457           /* If the parm list is terminated with a void type, it's
2458              fixed-length.  */
2459           varargs_p = 0;
2460           /* A void type better be the last one.  */
2461           gcc_assert (TREE_CHAIN (parm_types) == NULL);
2462         }
2463       else
2464         write_type (parm);
2465     }
2466
2467   if (varargs_p)
2468     /* <builtin-type> ::= z  # ellipsis  */
2469     write_char ('z');
2470 }
2471
2472 /* <class-enum-type> ::= <name>  */
2473
2474 static void
2475 write_class_enum_type (const tree type)
2476 {
2477   write_name (TYPE_NAME (type), /*ignore_local_scope=*/0);
2478 }
2479
2480 /* Non-terminal <template-args>.  ARGS is a TREE_VEC of template
2481    arguments.
2482
2483      <template-args> ::= I <template-arg>* E  */
2484
2485 static void
2486 write_template_args (tree args)
2487 {
2488   int i;
2489   int length = 0;
2490
2491   MANGLE_TRACE_TREE ("template-args", args);
2492
2493   write_char ('I');
2494
2495   if (args)
2496     length = TREE_VEC_LENGTH (args);
2497
2498   if (args && TREE_CODE (TREE_VEC_ELT (args, 0)) == TREE_VEC)
2499     {
2500       /* We have nested template args.  We want the innermost template
2501          argument list.  */
2502       args = TREE_VEC_ELT (args, length - 1);
2503       length = TREE_VEC_LENGTH (args);
2504     }
2505   for (i = 0; i < length; ++i)
2506     write_template_arg (TREE_VEC_ELT (args, i));
2507
2508   write_char ('E');
2509 }
2510
2511 /* Write out the
2512    <unqualified-name>
2513    <unqualified-name> <template-args>
2514    part of SCOPE_REF or COMPONENT_REF mangling.  */
2515
2516 static void
2517 write_member_name (tree member)
2518 {
2519   if (TREE_CODE (member) == IDENTIFIER_NODE)
2520     write_unqualified_id (member);
2521   else if (DECL_P (member))
2522     write_unqualified_name (member);
2523   else if (TREE_CODE (member) == TEMPLATE_ID_EXPR)
2524     {
2525       tree name = TREE_OPERAND (member, 0);
2526       if (TREE_CODE (name) == OVERLOAD)
2527         name = OVL_FUNCTION (name);
2528       write_member_name (name);
2529       write_template_args (TREE_OPERAND (member, 1));
2530     }
2531   else
2532     write_expression (member);
2533 }
2534
2535 /* <expression> ::= <unary operator-name> <expression>
2536                 ::= <binary operator-name> <expression> <expression>
2537                 ::= <expr-primary>
2538
2539    <expr-primary> ::= <template-param>
2540                   ::= L <type> <value number> E         # literal
2541                   ::= L <mangled-name> E                # external name
2542                   ::= st <type>                         # sizeof
2543                   ::= sr <type> <unqualified-name>      # dependent name
2544                   ::= sr <type> <unqualified-name> <template-args> */
2545
2546 static void
2547 write_expression (tree expr)
2548 {
2549   enum tree_code code = TREE_CODE (expr);
2550
2551   /* Skip NOP_EXPRs.  They can occur when (say) a pointer argument
2552      is converted (via qualification conversions) to another
2553      type.  */
2554   while (TREE_CODE (expr) == NOP_EXPR
2555          || TREE_CODE (expr) == NON_LVALUE_EXPR)
2556     {
2557       expr = TREE_OPERAND (expr, 0);
2558       code = TREE_CODE (expr);
2559     }
2560
2561   if (code == BASELINK
2562       && (!type_unknown_p (expr)
2563           || !BASELINK_QUALIFIED_P (expr)))
2564     {
2565       expr = BASELINK_FUNCTIONS (expr);
2566       code = TREE_CODE (expr);
2567     }
2568
2569   /* Handle pointers-to-members by making them look like expression
2570      nodes.  */
2571   if (code == PTRMEM_CST)
2572     {
2573       expr = build_nt (ADDR_EXPR,
2574                        build_qualified_name (/*type=*/NULL_TREE,
2575                                              PTRMEM_CST_CLASS (expr),
2576                                              PTRMEM_CST_MEMBER (expr),
2577                                              /*template_p=*/false));
2578       code = TREE_CODE (expr);
2579     }
2580
2581   /* Handle template parameters.  */
2582   if (code == TEMPLATE_TYPE_PARM
2583       || code == TEMPLATE_TEMPLATE_PARM
2584       || code == BOUND_TEMPLATE_TEMPLATE_PARM
2585       || code == TEMPLATE_PARM_INDEX)
2586     write_template_param (expr);
2587   /* Handle literals.  */
2588   else if (TREE_CODE_CLASS (code) == tcc_constant
2589            || (abi_version_at_least (2) && code == CONST_DECL))
2590     write_template_arg_literal (expr);
2591   else if (code == PARM_DECL && DECL_ARTIFICIAL (expr))
2592     {
2593       gcc_assert (!strcmp ("this", IDENTIFIER_POINTER (DECL_NAME (expr))));
2594       write_string ("fpT");
2595     }
2596   else if (code == PARM_DECL)
2597     {
2598       /* A function parameter used in a late-specified return type.  */
2599       int index = DECL_PARM_INDEX (expr);
2600       int level = DECL_PARM_LEVEL (expr);
2601       int delta = G.parm_depth - level + 1;
2602       gcc_assert (index >= 1);
2603       write_char ('f');
2604       if (delta != 0)
2605         {
2606           if (abi_version_at_least (5))
2607             {
2608               /* Let L be the number of function prototype scopes from the
2609                  innermost one (in which the parameter reference occurs) up
2610                  to (and including) the one containing the declaration of
2611                  the referenced parameter.  If the parameter declaration
2612                  clause of the innermost function prototype scope has been
2613                  completely seen, it is not counted (in that case -- which
2614                  is perhaps the most common -- L can be zero).  */
2615               write_char ('L');
2616               write_unsigned_number (delta - 1);
2617             }
2618           else
2619             G.need_abi_warning = true;
2620         }
2621       write_char ('p');
2622       write_compact_number (index - 1);
2623     }
2624   else if (DECL_P (expr))
2625     {
2626       /* G++ 3.2 incorrectly mangled non-type template arguments of
2627          enumeration type using their names.  */
2628       if (code == CONST_DECL)
2629         G.need_abi_warning = 1;
2630       write_char ('L');
2631       write_mangled_name (expr, false);
2632       write_char ('E');
2633     }
2634   else if (TREE_CODE (expr) == SIZEOF_EXPR
2635            && SIZEOF_EXPR_TYPE_P (expr))
2636     {
2637       write_string ("st");
2638       write_type (TREE_TYPE (TREE_OPERAND (expr, 0)));
2639     }
2640   else if (TREE_CODE (expr) == SIZEOF_EXPR
2641            && TYPE_P (TREE_OPERAND (expr, 0)))
2642     {
2643       write_string ("st");
2644       write_type (TREE_OPERAND (expr, 0));
2645     }
2646   else if (TREE_CODE (expr) == ALIGNOF_EXPR
2647            && TYPE_P (TREE_OPERAND (expr, 0)))
2648     {
2649       write_string ("at");
2650       write_type (TREE_OPERAND (expr, 0));
2651     }
2652   else if (code == SCOPE_REF
2653            || code == BASELINK)
2654     {
2655       tree scope, member;
2656       if (code == SCOPE_REF)
2657         {
2658           scope = TREE_OPERAND (expr, 0);
2659           member = TREE_OPERAND (expr, 1);
2660         }
2661       else
2662         {
2663           scope = BINFO_TYPE (BASELINK_ACCESS_BINFO (expr));
2664           member = BASELINK_FUNCTIONS (expr);
2665         }
2666
2667       if (!abi_version_at_least (2) && DECL_P (member))
2668         {
2669           write_string ("sr");
2670           write_type (scope);
2671           /* G++ 3.2 incorrectly put out both the "sr" code and
2672              the nested name of the qualified name.  */
2673           G.need_abi_warning = 1;
2674           write_encoding (member);
2675         }
2676
2677       /* If the MEMBER is a real declaration, then the qualifying
2678          scope was not dependent.  Ideally, we would not have a
2679          SCOPE_REF in those cases, but sometimes we do.  If the second
2680          argument is a DECL, then the name must not have been
2681          dependent.  */
2682       else if (DECL_P (member))
2683         write_expression (member);
2684       else
2685         {
2686           write_string ("sr");
2687           write_type (scope);
2688           write_member_name (member);
2689         }
2690     }
2691   else if (TREE_CODE (expr) == INDIRECT_REF
2692            && TREE_TYPE (TREE_OPERAND (expr, 0))
2693            && TREE_CODE (TREE_TYPE (TREE_OPERAND (expr, 0))) == REFERENCE_TYPE)
2694     {
2695       write_expression (TREE_OPERAND (expr, 0));
2696     }
2697   else if (TREE_CODE (expr) == IDENTIFIER_NODE)
2698     {
2699       /* An operator name appearing as a dependent name needs to be
2700          specially marked to disambiguate between a use of the operator
2701          name and a use of the operator in an expression.  */
2702       if (IDENTIFIER_OPNAME_P (expr))
2703         write_string ("on");
2704       write_unqualified_id (expr);
2705     }
2706   else if (TREE_CODE (expr) == TEMPLATE_ID_EXPR)
2707     {
2708       tree fn = TREE_OPERAND (expr, 0);
2709       if (is_overloaded_fn (fn))
2710         fn = DECL_NAME (get_first_fn (fn));
2711       if (IDENTIFIER_OPNAME_P (fn))
2712         write_string ("on");
2713       write_unqualified_id (fn);
2714       write_template_args (TREE_OPERAND (expr, 1));
2715     }
2716   else if (TREE_CODE (expr) == MODOP_EXPR)
2717     {
2718       enum tree_code subop = TREE_CODE (TREE_OPERAND (expr, 1));
2719       const char *name = (assignment_operator_name_info[(int) subop]
2720                           .mangled_name);
2721       write_string (name);
2722       write_expression (TREE_OPERAND (expr, 0));
2723       write_expression (TREE_OPERAND (expr, 2));
2724     }
2725   else if (code == NEW_EXPR || code == VEC_NEW_EXPR)
2726     {
2727       /* ::= [gs] nw <expression>* _ <type> E
2728          ::= [gs] nw <expression>* _ <type> <initializer>
2729          ::= [gs] na <expression>* _ <type> E
2730          ::= [gs] na <expression>* _ <type> <initializer>
2731          <initializer> ::= pi <expression>* E  */
2732       tree placement = TREE_OPERAND (expr, 0);
2733       tree type = TREE_OPERAND (expr, 1);
2734       tree nelts = TREE_OPERAND (expr, 2);
2735       tree init = TREE_OPERAND (expr, 3);
2736       tree t;
2737
2738       gcc_assert (code == NEW_EXPR);
2739       if (TREE_OPERAND (expr, 2))
2740         code = VEC_NEW_EXPR;
2741
2742       if (NEW_EXPR_USE_GLOBAL (expr))
2743         write_string ("gs");
2744
2745       write_string (operator_name_info[(int) code].mangled_name);
2746
2747       for (t = placement; t; t = TREE_CHAIN (t))
2748         write_expression (TREE_VALUE (t));
2749
2750       write_char ('_');
2751
2752       if (nelts)
2753         {
2754           tree domain;
2755           ++processing_template_decl;
2756           domain = compute_array_index_type (NULL_TREE, nelts,
2757                                              tf_warning_or_error);
2758           type = build_cplus_array_type (type, domain);
2759           --processing_template_decl;
2760         }
2761       write_type (type);
2762
2763       if (init && TREE_CODE (init) == TREE_LIST
2764           && TREE_CODE (TREE_VALUE (init)) == CONSTRUCTOR
2765           && CONSTRUCTOR_IS_DIRECT_INIT (TREE_VALUE (init)))
2766         write_expression (TREE_VALUE (init));
2767       else
2768         {
2769           if (init)
2770             write_string ("pi");
2771           if (init && init != void_zero_node)
2772             for (t = init; t; t = TREE_CHAIN (t))
2773               write_expression (TREE_VALUE (t));
2774           write_char ('E');
2775         }
2776     }
2777   else if (code == DELETE_EXPR || code == VEC_DELETE_EXPR)
2778     {
2779       gcc_assert (code == DELETE_EXPR);
2780       if (DELETE_EXPR_USE_VEC (expr))
2781         code = VEC_DELETE_EXPR;
2782
2783       if (DELETE_EXPR_USE_GLOBAL (expr))
2784         write_string ("gs");
2785
2786       write_string (operator_name_info[(int) code].mangled_name);
2787
2788       write_expression (TREE_OPERAND (expr, 0));
2789     }
2790   else if (code == THROW_EXPR)
2791     {
2792       tree op = TREE_OPERAND (expr, 0);
2793       if (op)
2794         {
2795           write_string ("tw");
2796           write_expression (op);
2797         }
2798       else
2799         write_string ("tr");
2800     }
2801   else if (code == CONSTRUCTOR)
2802     {
2803       vec<constructor_elt, va_gc> *elts = CONSTRUCTOR_ELTS (expr);
2804       unsigned i; tree val;
2805
2806       if (BRACE_ENCLOSED_INITIALIZER_P (expr))
2807         write_string ("il");
2808       else
2809         {
2810           write_string ("tl");
2811           write_type (TREE_TYPE (expr));
2812         }
2813       FOR_EACH_CONSTRUCTOR_VALUE (elts, i, val)
2814         write_expression (val);
2815       write_char ('E');
2816     }
2817   else if (dependent_name (expr))
2818     {
2819       write_unqualified_id (dependent_name (expr));
2820     }
2821   else
2822     {
2823       int i, len;
2824       const char *name;
2825
2826       /* When we bind a variable or function to a non-type template
2827          argument with reference type, we create an ADDR_EXPR to show
2828          the fact that the entity's address has been taken.  But, we
2829          don't actually want to output a mangling code for the `&'.  */
2830       if (TREE_CODE (expr) == ADDR_EXPR
2831           && TREE_TYPE (expr)
2832           && TREE_CODE (TREE_TYPE (expr)) == REFERENCE_TYPE)
2833         {
2834           expr = TREE_OPERAND (expr, 0);
2835           if (DECL_P (expr))
2836             {
2837               write_expression (expr);
2838               return;
2839             }
2840
2841           code = TREE_CODE (expr);
2842         }
2843
2844       if (code == COMPONENT_REF)
2845         {
2846           tree ob = TREE_OPERAND (expr, 0);
2847
2848           if (TREE_CODE (ob) == ARROW_EXPR)
2849             {
2850               write_string (operator_name_info[(int)code].mangled_name);
2851               ob = TREE_OPERAND (ob, 0);
2852             }
2853           else
2854             write_string ("dt");
2855
2856           write_expression (ob);
2857           write_member_name (TREE_OPERAND (expr, 1));
2858           return;
2859         }
2860
2861       /* If it wasn't any of those, recursively expand the expression.  */
2862       name = operator_name_info[(int) code].mangled_name;
2863
2864       /* We used to mangle const_cast and static_cast like a C cast.  */
2865       if (!abi_version_at_least (6)
2866           && (code == CONST_CAST_EXPR
2867               || code == STATIC_CAST_EXPR))
2868         {
2869           name = operator_name_info[CAST_EXPR].mangled_name;
2870           G.need_abi_warning = 1;
2871         }
2872
2873       if (name == NULL)
2874         {
2875           switch (code)
2876             {
2877             case TRAIT_EXPR:
2878               error ("use of built-in trait %qE in function signature; "
2879                      "use library traits instead", expr);
2880               break;
2881
2882             default:
2883               sorry ("mangling %C", code);
2884               break;
2885             }
2886           return;
2887         }
2888       else
2889         write_string (name);
2890
2891       switch (code)
2892         {
2893         case CALL_EXPR:
2894           {
2895             tree fn = CALL_EXPR_FN (expr);
2896
2897             if (TREE_CODE (fn) == ADDR_EXPR)
2898               fn = TREE_OPERAND (fn, 0);
2899
2900             /* Mangle a dependent name as the name, not whatever happens to
2901                be the first function in the overload set.  */
2902             if ((TREE_CODE (fn) == FUNCTION_DECL
2903                  || TREE_CODE (fn) == OVERLOAD)
2904                 && type_dependent_expression_p_push (expr))
2905               fn = DECL_NAME (get_first_fn (fn));
2906
2907             write_expression (fn);
2908           }
2909
2910           for (i = 0; i < call_expr_nargs (expr); ++i)
2911             write_expression (CALL_EXPR_ARG (expr, i));
2912           write_char ('E');
2913           break;
2914
2915         case CAST_EXPR:
2916           write_type (TREE_TYPE (expr));
2917           if (list_length (TREE_OPERAND (expr, 0)) == 1)
2918             write_expression (TREE_VALUE (TREE_OPERAND (expr, 0)));
2919           else
2920             {
2921               tree args = TREE_OPERAND (expr, 0);
2922               write_char ('_');
2923               for (; args; args = TREE_CHAIN (args))
2924                 write_expression (TREE_VALUE (args));
2925               write_char ('E');
2926             }
2927           break;
2928
2929         case DYNAMIC_CAST_EXPR:
2930         case REINTERPRET_CAST_EXPR:
2931         case STATIC_CAST_EXPR:
2932         case CONST_CAST_EXPR:
2933           write_type (TREE_TYPE (expr));
2934           write_expression (TREE_OPERAND (expr, 0));
2935           break;
2936
2937         case PREINCREMENT_EXPR:
2938         case PREDECREMENT_EXPR:
2939           if (abi_version_at_least (6))
2940             write_char ('_');
2941           else
2942             G.need_abi_warning = 1;
2943           /* Fall through.  */
2944
2945         default:
2946           /* In the middle-end, some expressions have more operands than
2947              they do in templates (and mangling).  */
2948           len = cp_tree_operand_length (expr);
2949
2950           for (i = 0; i < len; ++i)
2951             {
2952               tree operand = TREE_OPERAND (expr, i);
2953               /* As a GNU extension, the middle operand of a
2954                  conditional may be omitted.  Since expression
2955                  manglings are supposed to represent the input token
2956                  stream, there's no good way to mangle such an
2957                  expression without extending the C++ ABI.  */
2958               if (code == COND_EXPR && i == 1 && !operand)
2959                 {
2960                   error ("omitted middle operand to %<?:%> operand "
2961                          "cannot be mangled");
2962                   continue;
2963                 }
2964               write_expression (operand);
2965             }
2966         }
2967     }
2968 }
2969
2970 /* Literal subcase of non-terminal <template-arg>.
2971
2972      "Literal arguments, e.g. "A<42L>", are encoded with their type
2973      and value. Negative integer values are preceded with "n"; for
2974      example, "A<-42L>" becomes "1AILln42EE". The bool value false is
2975      encoded as 0, true as 1."  */
2976
2977 static void
2978 write_template_arg_literal (const tree value)
2979 {
2980   write_char ('L');
2981   write_type (TREE_TYPE (value));
2982
2983   /* Write a null member pointer value as (type)0, regardless of its
2984      real representation.  */
2985   if (null_member_pointer_value_p (value))
2986     write_integer_cst (integer_zero_node);
2987   else
2988     switch (TREE_CODE (value))
2989       {
2990       case CONST_DECL:
2991         write_integer_cst (DECL_INITIAL (value));
2992         break;
2993
2994       case INTEGER_CST:
2995         gcc_assert (!same_type_p (TREE_TYPE (value), boolean_type_node)
2996                     || integer_zerop (value) || integer_onep (value));
2997         write_integer_cst (value);
2998         break;
2999
3000       case REAL_CST:
3001         write_real_cst (value);
3002         break;
3003
3004       case COMPLEX_CST:
3005         if (TREE_CODE (TREE_REALPART (value)) == INTEGER_CST
3006             && TREE_CODE (TREE_IMAGPART (value)) == INTEGER_CST)
3007           {
3008             write_integer_cst (TREE_REALPART (value));
3009             write_char ('_');
3010             write_integer_cst (TREE_IMAGPART (value));
3011           }
3012         else if (TREE_CODE (TREE_REALPART (value)) == REAL_CST
3013                  && TREE_CODE (TREE_IMAGPART (value)) == REAL_CST)
3014           {
3015             write_real_cst (TREE_REALPART (value));
3016             write_char ('_');
3017             write_real_cst (TREE_IMAGPART (value));
3018           }
3019         else
3020           gcc_unreachable ();
3021         break;
3022
3023       case STRING_CST:
3024         sorry ("string literal in function template signature");
3025         break;
3026
3027       default:
3028         gcc_unreachable ();
3029       }
3030
3031   write_char ('E');
3032 }
3033
3034 /* Non-terminal <template-arg>.
3035
3036      <template-arg> ::= <type>                          # type
3037                     ::= L <type> </value/ number> E     # literal
3038                     ::= LZ <name> E                     # external name
3039                     ::= X <expression> E                # expression  */
3040
3041 static void
3042 write_template_arg (tree node)
3043 {
3044   enum tree_code code = TREE_CODE (node);
3045
3046   MANGLE_TRACE_TREE ("template-arg", node);
3047
3048   /* A template template parameter's argument list contains TREE_LIST
3049      nodes of which the value field is the actual argument.  */
3050   if (code == TREE_LIST)
3051     {
3052       node = TREE_VALUE (node);
3053       /* If it's a decl, deal with its type instead.  */
3054       if (DECL_P (node))
3055         {
3056           node = TREE_TYPE (node);
3057           code = TREE_CODE (node);
3058         }
3059     }
3060
3061   if (TREE_CODE (node) == NOP_EXPR
3062       && TREE_CODE (TREE_TYPE (node)) == REFERENCE_TYPE)
3063     {
3064       /* Template parameters can be of reference type. To maintain
3065          internal consistency, such arguments use a conversion from
3066          address of object to reference type.  */
3067       gcc_assert (TREE_CODE (TREE_OPERAND (node, 0)) == ADDR_EXPR);
3068       if (abi_version_at_least (2))
3069         node = TREE_OPERAND (TREE_OPERAND (node, 0), 0);
3070       else
3071         G.need_abi_warning = 1;
3072     }
3073
3074   if (TREE_CODE (node) == BASELINK
3075       && !type_unknown_p (node))
3076     {
3077       if (abi_version_at_least (6))
3078         node = BASELINK_FUNCTIONS (node);
3079       else
3080         /* We wrongly wrapped a class-scope function in X/E.  */
3081         G.need_abi_warning = 1;
3082     }
3083
3084   if (ARGUMENT_PACK_P (node))
3085     {
3086       /* Expand the template argument pack. */
3087       tree args = ARGUMENT_PACK_ARGS (node);
3088       int i, length = TREE_VEC_LENGTH (args);
3089       if (abi_version_at_least (6))
3090         write_char ('J');
3091       else
3092         {
3093           write_char ('I');
3094           G.need_abi_warning = 1;
3095         }
3096       for (i = 0; i < length; ++i)
3097         write_template_arg (TREE_VEC_ELT (args, i));
3098       write_char ('E');
3099     }
3100   else if (TYPE_P (node))
3101     write_type (node);
3102   else if (code == TEMPLATE_DECL)
3103     /* A template appearing as a template arg is a template template arg.  */
3104     write_template_template_arg (node);
3105   else if ((TREE_CODE_CLASS (code) == tcc_constant && code != PTRMEM_CST)
3106            || (abi_version_at_least (2) && code == CONST_DECL)
3107            || null_member_pointer_value_p (node))
3108     write_template_arg_literal (node);
3109   else if (DECL_P (node))
3110     {
3111       /* Until ABI version 2, non-type template arguments of
3112          enumeration type were mangled using their names.  */
3113       if (code == CONST_DECL && !abi_version_at_least (2))
3114         G.need_abi_warning = 1;
3115       write_char ('L');
3116       /* Until ABI version 3, the underscore before the mangled name
3117          was incorrectly omitted.  */
3118       if (!abi_version_at_least (3))
3119         {
3120           G.need_abi_warning = 1;
3121           write_char ('Z');
3122         }
3123       else
3124         write_string ("_Z");
3125       write_encoding (node);
3126       write_char ('E');
3127     }
3128   else
3129     {
3130       /* Template arguments may be expressions.  */
3131       write_char ('X');
3132       write_expression (node);
3133       write_char ('E');
3134     }
3135 }
3136
3137 /*  <template-template-arg>
3138                         ::= <name>
3139                         ::= <substitution>  */
3140
3141 static void
3142 write_template_template_arg (const tree decl)
3143 {
3144   MANGLE_TRACE_TREE ("template-template-arg", decl);
3145
3146   if (find_substitution (decl))
3147     return;
3148   write_name (decl, /*ignore_local_scope=*/0);
3149   add_substitution (decl);
3150 }
3151
3152
3153 /* Non-terminal <array-type>.  TYPE is an ARRAY_TYPE.
3154
3155      <array-type> ::= A [</dimension/ number>] _ </element/ type>
3156                   ::= A <expression> _ </element/ type>
3157
3158      "Array types encode the dimension (number of elements) and the
3159      element type. For variable length arrays, the dimension (but not
3160      the '_' separator) is omitted."  */
3161
3162 static void
3163 write_array_type (const tree type)
3164 {
3165   write_char ('A');
3166   if (TYPE_DOMAIN (type))
3167     {
3168       tree index_type;
3169       tree max;
3170
3171       index_type = TYPE_DOMAIN (type);
3172       /* The INDEX_TYPE gives the upper and lower bounds of the
3173          array.  */
3174       max = TYPE_MAX_VALUE (index_type);
3175       if (TREE_CODE (max) == INTEGER_CST)
3176         {
3177           /* The ABI specifies that we should mangle the number of
3178              elements in the array, not the largest allowed index.  */
3179           double_int dmax = tree_to_double_int (max) + double_int_one;
3180           /* Truncate the result - this will mangle [0, SIZE_INT_MAX]
3181              number of elements as zero.  */
3182           dmax = dmax.zext (TYPE_PRECISION (TREE_TYPE (max)));
3183           gcc_assert (dmax.fits_uhwi ());
3184           write_unsigned_number (dmax.low);
3185         }
3186       else
3187         {
3188           max = TREE_OPERAND (max, 0);
3189           if (!abi_version_at_least (2))
3190             {
3191               /* value_dependent_expression_p presumes nothing is
3192                  dependent when PROCESSING_TEMPLATE_DECL is zero.  */
3193               ++processing_template_decl;
3194               if (!value_dependent_expression_p (max))
3195                 G.need_abi_warning = 1;
3196               --processing_template_decl;
3197             }
3198           write_expression (max);
3199         }
3200
3201     }
3202   write_char ('_');
3203   write_type (TREE_TYPE (type));
3204 }
3205
3206 /* Non-terminal <pointer-to-member-type> for pointer-to-member
3207    variables.  TYPE is a pointer-to-member POINTER_TYPE.
3208
3209      <pointer-to-member-type> ::= M </class/ type> </member/ type>  */
3210
3211 static void
3212 write_pointer_to_member_type (const tree type)
3213 {
3214   write_char ('M');
3215   write_type (TYPE_PTRMEM_CLASS_TYPE (type));
3216   write_type (TYPE_PTRMEM_POINTED_TO_TYPE (type));
3217 }
3218
3219 /* Non-terminal <template-param>.  PARM is a TEMPLATE_TYPE_PARM,
3220    TEMPLATE_TEMPLATE_PARM, BOUND_TEMPLATE_TEMPLATE_PARM or a
3221    TEMPLATE_PARM_INDEX.
3222
3223      <template-param> ::= T </parameter/ number> _  */
3224
3225 static void
3226 write_template_param (const tree parm)
3227 {
3228   int parm_index;
3229
3230   MANGLE_TRACE_TREE ("template-parm", parm);
3231
3232   switch (TREE_CODE (parm))
3233     {
3234     case TEMPLATE_TYPE_PARM:
3235     case TEMPLATE_TEMPLATE_PARM:
3236     case BOUND_TEMPLATE_TEMPLATE_PARM:
3237       parm_index = TEMPLATE_TYPE_IDX (parm);
3238       break;
3239
3240     case TEMPLATE_PARM_INDEX:
3241       parm_index = TEMPLATE_PARM_IDX (parm);
3242       break;
3243
3244     default:
3245       gcc_unreachable ();
3246     }
3247
3248   write_char ('T');
3249   /* NUMBER as it appears in the mangling is (-1)-indexed, with the
3250      earliest template param denoted by `_'.  */
3251   write_compact_number (parm_index);
3252 }
3253
3254 /*  <template-template-param>
3255                         ::= <template-param>
3256                         ::= <substitution>  */
3257
3258 static void
3259 write_template_template_param (const tree parm)
3260 {
3261   tree templ = NULL_TREE;
3262
3263   /* PARM, a TEMPLATE_TEMPLATE_PARM, is an instantiation of the
3264      template template parameter.  The substitution candidate here is
3265      only the template.  */
3266   if (TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
3267     {
3268       templ
3269         = TI_TEMPLATE (TEMPLATE_TEMPLATE_PARM_TEMPLATE_INFO (parm));
3270       if (find_substitution (templ))
3271         return;
3272     }
3273
3274   /* <template-param> encodes only the template parameter position,
3275      not its template arguments, which is fine here.  */
3276   write_template_param (parm);
3277   if (templ)
3278     add_substitution (templ);
3279 }
3280
3281 /* Non-terminal <substitution>.
3282
3283       <substitution> ::= S <seq-id> _
3284                      ::= S_  */
3285
3286 static void
3287 write_substitution (const int seq_id)
3288 {
3289   MANGLE_TRACE ("substitution", "");
3290
3291   write_char ('S');
3292   if (seq_id > 0)
3293     write_number (seq_id - 1, /*unsigned=*/1, 36);
3294   write_char ('_');
3295 }
3296
3297 /* Start mangling ENTITY.  */
3298
3299 static inline void
3300 start_mangling (const tree entity)
3301 {
3302   G.entity = entity;
3303   G.need_abi_warning = false;
3304   obstack_free (&name_obstack, name_base);
3305   mangle_obstack = &name_obstack;
3306   name_base = obstack_alloc (&name_obstack, 0);
3307 }
3308
3309 /* Done with mangling. If WARN is true, and the name of G.entity will
3310    be mangled differently in a future version of the ABI, issue a
3311    warning.  */
3312
3313 static void
3314 finish_mangling_internal (const bool warn)
3315 {
3316   if (warn_abi && warn && G.need_abi_warning)
3317     warning (OPT_Wabi, "the mangled name of %qD will change in a future "
3318              "version of GCC",
3319              G.entity);
3320
3321   /* Clear all the substitutions.  */
3322   vec_safe_truncate (G.substitutions, 0);
3323
3324   /* Null-terminate the string.  */
3325   write_char ('\0');
3326 }
3327
3328
3329 /* Like finish_mangling_internal, but return the mangled string.  */
3330
3331 static inline const char *
3332 finish_mangling (const bool warn)
3333 {
3334   finish_mangling_internal (warn);
3335   return (const char *) obstack_finish (mangle_obstack);
3336 }
3337
3338 /* Like finish_mangling_internal, but return an identifier.  */
3339
3340 static tree
3341 finish_mangling_get_identifier (const bool warn)
3342 {
3343   finish_mangling_internal (warn);
3344   /* Don't obstack_finish here, and the next start_mangling will
3345      remove the identifier.  */
3346   return get_identifier ((const char *) obstack_base (mangle_obstack));
3347 }
3348
3349 /* Initialize data structures for mangling.  */
3350
3351 void
3352 init_mangle (void)
3353 {
3354   gcc_obstack_init (&name_obstack);
3355   name_base = obstack_alloc (&name_obstack, 0);
3356   vec_alloc (G.substitutions, 0);
3357
3358   /* Cache these identifiers for quick comparison when checking for
3359      standard substitutions.  */
3360   subst_identifiers[SUBID_ALLOCATOR] = get_identifier ("allocator");
3361   subst_identifiers[SUBID_BASIC_STRING] = get_identifier ("basic_string");
3362   subst_identifiers[SUBID_CHAR_TRAITS] = get_identifier ("char_traits");
3363   subst_identifiers[SUBID_BASIC_ISTREAM] = get_identifier ("basic_istream");
3364   subst_identifiers[SUBID_BASIC_OSTREAM] = get_identifier ("basic_ostream");
3365   subst_identifiers[SUBID_BASIC_IOSTREAM] = get_identifier ("basic_iostream");
3366 }
3367
3368 /* Generate the mangled name of DECL.  */
3369
3370 static tree
3371 mangle_decl_string (const tree decl)
3372 {
3373   tree result;
3374   location_t saved_loc = input_location;
3375   tree saved_fn = NULL_TREE;
3376   bool template_p = false;
3377
3378   /* We shouldn't be trying to mangle an uninstantiated template.  */
3379   gcc_assert (!type_dependent_expression_p (decl));
3380
3381   if (DECL_LANG_SPECIFIC (decl) && DECL_USE_TEMPLATE (decl))
3382     {
3383       struct tinst_level *tl = current_instantiation ();
3384       if ((!tl || tl->decl != decl)
3385           && push_tinst_level (decl))
3386         {
3387           template_p = true;
3388           saved_fn = current_function_decl;
3389           current_function_decl = NULL_TREE;
3390         }
3391     }
3392   input_location = DECL_SOURCE_LOCATION (decl);
3393
3394   start_mangling (decl);
3395
3396   if (TREE_CODE (decl) == TYPE_DECL)
3397     write_type (TREE_TYPE (decl));
3398   else
3399     write_mangled_name (decl, true);
3400
3401   result = finish_mangling_get_identifier (/*warn=*/true);
3402   if (DEBUG_MANGLE)
3403     fprintf (stderr, "mangle_decl_string = '%s'\n\n",
3404              IDENTIFIER_POINTER (result));
3405
3406   if (template_p)
3407     {
3408       pop_tinst_level ();
3409       current_function_decl = saved_fn;
3410     }
3411   input_location = saved_loc;
3412
3413   return result;
3414 }
3415
3416 /* Return an identifier for the external mangled name of DECL.  */
3417
3418 static tree
3419 get_mangled_id (tree decl)
3420 {
3421   tree id = mangle_decl_string (decl);
3422   return targetm.mangle_decl_assembler_name (decl, id);
3423 }
3424
3425 /* Create an identifier for the external mangled name of DECL.  */
3426
3427 void
3428 mangle_decl (const tree decl)
3429 {
3430   tree id;
3431   bool dep;
3432
3433   /* Don't bother mangling uninstantiated templates.  */
3434   ++processing_template_decl;
3435   if (TREE_CODE (decl) == TYPE_DECL)
3436     dep = dependent_type_p (TREE_TYPE (decl));
3437   else
3438     dep = (DECL_LANG_SPECIFIC (decl) && DECL_TEMPLATE_INFO (decl)
3439            && any_dependent_template_arguments_p (DECL_TI_ARGS (decl)));
3440   --processing_template_decl;
3441   if (dep)
3442     return;
3443
3444   id = get_mangled_id (decl);
3445   SET_DECL_ASSEMBLER_NAME (decl, id);
3446
3447   if (G.need_abi_warning
3448       /* Don't do this for a fake symbol we aren't going to emit anyway.  */
3449       && !DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (decl)
3450       && !DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (decl))
3451     {
3452 #ifdef ASM_OUTPUT_DEF
3453       /* If the mangling will change in the future, emit an alias with the
3454          future mangled name for forward-compatibility.  */
3455       int save_ver;
3456       tree id2, alias;
3457 #endif
3458
3459       SET_IDENTIFIER_GLOBAL_VALUE (id, decl);
3460       if (IDENTIFIER_GLOBAL_VALUE (id) != decl)
3461         inform (DECL_SOURCE_LOCATION (decl), "-fabi-version=6 (or =0) "
3462                 "avoids this error with a change in mangling");
3463
3464 #ifdef ASM_OUTPUT_DEF
3465       save_ver = flag_abi_version;
3466       flag_abi_version = 0;
3467       id2 = mangle_decl_string (decl);
3468       id2 = targetm.mangle_decl_assembler_name (decl, id2);
3469       flag_abi_version = save_ver;
3470
3471       alias = make_alias_for (decl, id2);
3472       DECL_IGNORED_P (alias) = 1;
3473       TREE_PUBLIC (alias) = TREE_PUBLIC (decl);
3474       DECL_VISIBILITY (alias) = DECL_VISIBILITY (decl);
3475       if (vague_linkage_p (decl))
3476         DECL_WEAK (alias) = 1;
3477       if (TREE_CODE (decl) == FUNCTION_DECL)
3478         cgraph_same_body_alias (cgraph_get_create_node (decl), alias, decl);
3479       else
3480         varpool_extra_name_alias (alias, decl);
3481 #endif
3482     }
3483 }
3484
3485 /* Generate the mangled representation of TYPE.  */
3486
3487 const char *
3488 mangle_type_string (const tree type)
3489 {
3490   const char *result;
3491
3492   start_mangling (type);
3493   write_type (type);
3494   result = finish_mangling (/*warn=*/false);
3495   if (DEBUG_MANGLE)
3496     fprintf (stderr, "mangle_type_string = '%s'\n\n", result);
3497   return result;
3498 }
3499
3500 /* Create an identifier for the mangled name of a special component
3501    for belonging to TYPE.  CODE is the ABI-specified code for this
3502    component.  */
3503
3504 static tree
3505 mangle_special_for_type (const tree type, const char *code)
3506 {
3507   tree result;
3508
3509   /* We don't have an actual decl here for the special component, so
3510      we can't just process the <encoded-name>.  Instead, fake it.  */
3511   start_mangling (type);
3512
3513   /* Start the mangling.  */
3514   write_string ("_Z");
3515   write_string (code);
3516
3517   /* Add the type.  */
3518   write_type (type);
3519   result = finish_mangling_get_identifier (/*warn=*/false);
3520
3521   if (DEBUG_MANGLE)
3522     fprintf (stderr, "mangle_special_for_type = %s\n\n",
3523              IDENTIFIER_POINTER (result));
3524
3525   return result;
3526 }
3527
3528 /* Create an identifier for the mangled representation of the typeinfo
3529    structure for TYPE.  */
3530
3531 tree
3532 mangle_typeinfo_for_type (const tree type)
3533 {
3534   return mangle_special_for_type (type, "TI");
3535 }
3536
3537 /* Create an identifier for the mangled name of the NTBS containing
3538    the mangled name of TYPE.  */
3539
3540 tree
3541 mangle_typeinfo_string_for_type (const tree type)
3542 {
3543   return mangle_special_for_type (type, "TS");
3544 }
3545
3546 /* Create an identifier for the mangled name of the vtable for TYPE.  */
3547
3548 tree
3549 mangle_vtbl_for_type (const tree type)
3550 {
3551   return mangle_special_for_type (type, "TV");
3552 }
3553
3554 /* Returns an identifier for the mangled name of the VTT for TYPE.  */
3555
3556 tree
3557 mangle_vtt_for_type (const tree type)
3558 {
3559   return mangle_special_for_type (type, "TT");
3560 }
3561
3562 /* Return an identifier for a construction vtable group.  TYPE is
3563    the most derived class in the hierarchy; BINFO is the base
3564    subobject for which this construction vtable group will be used.
3565
3566    This mangling isn't part of the ABI specification; in the ABI
3567    specification, the vtable group is dumped in the same COMDAT as the
3568    main vtable, and is referenced only from that vtable, so it doesn't
3569    need an external name.  For binary formats without COMDAT sections,
3570    though, we need external names for the vtable groups.
3571
3572    We use the production
3573
3574     <special-name> ::= CT <type> <offset number> _ <base type>  */
3575
3576 tree
3577 mangle_ctor_vtbl_for_type (const tree type, const tree binfo)
3578 {
3579   tree result;
3580
3581   start_mangling (type);
3582
3583   write_string ("_Z");
3584   write_string ("TC");
3585   write_type (type);
3586   write_integer_cst (BINFO_OFFSET (binfo));
3587   write_char ('_');
3588   write_type (BINFO_TYPE (binfo));
3589
3590   result = finish_mangling_get_identifier (/*warn=*/false);
3591   if (DEBUG_MANGLE)
3592     fprintf (stderr, "mangle_ctor_vtbl_for_type = %s\n\n",
3593              IDENTIFIER_POINTER (result));
3594   return result;
3595 }
3596
3597 /* Mangle a this pointer or result pointer adjustment.
3598
3599    <call-offset> ::= h <fixed offset number> _
3600                  ::= v <fixed offset number> _ <virtual offset number> _ */
3601
3602 static void
3603 mangle_call_offset (const tree fixed_offset, const tree virtual_offset)
3604 {
3605   write_char (virtual_offset ? 'v' : 'h');
3606
3607   /* For either flavor, write the fixed offset.  */
3608   write_integer_cst (fixed_offset);
3609   write_char ('_');
3610
3611   /* For a virtual thunk, add the virtual offset.  */
3612   if (virtual_offset)
3613     {
3614       write_integer_cst (virtual_offset);
3615       write_char ('_');
3616     }
3617 }
3618
3619 /* Return an identifier for the mangled name of a this-adjusting or
3620    covariant thunk to FN_DECL.  FIXED_OFFSET is the initial adjustment
3621    to this used to find the vptr.  If VIRTUAL_OFFSET is non-NULL, this
3622    is a virtual thunk, and it is the vtbl offset in
3623    bytes. THIS_ADJUSTING is nonzero for a this adjusting thunk and
3624    zero for a covariant thunk. Note, that FN_DECL might be a covariant
3625    thunk itself. A covariant thunk name always includes the adjustment
3626    for the this pointer, even if there is none.
3627
3628    <special-name> ::= T <call-offset> <base encoding>
3629                   ::= Tc <this_adjust call-offset> <result_adjust call-offset>
3630                                         <base encoding>  */
3631
3632 tree
3633 mangle_thunk (tree fn_decl, const int this_adjusting, tree fixed_offset,
3634               tree virtual_offset)
3635 {
3636   tree result;
3637
3638   start_mangling (fn_decl);
3639
3640   write_string ("_Z");
3641   write_char ('T');
3642
3643   if (!this_adjusting)
3644     {
3645       /* Covariant thunk with no this adjustment */
3646       write_char ('c');
3647       mangle_call_offset (integer_zero_node, NULL_TREE);
3648       mangle_call_offset (fixed_offset, virtual_offset);
3649     }
3650   else if (!DECL_THUNK_P (fn_decl))
3651     /* Plain this adjusting thunk.  */
3652     mangle_call_offset (fixed_offset, virtual_offset);
3653   else
3654     {
3655       /* This adjusting thunk to covariant thunk.  */
3656       write_char ('c');
3657       mangle_call_offset (fixed_offset, virtual_offset);
3658       fixed_offset = ssize_int (THUNK_FIXED_OFFSET (fn_decl));
3659       virtual_offset = THUNK_VIRTUAL_OFFSET (fn_decl);
3660       if (virtual_offset)
3661         virtual_offset = BINFO_VPTR_FIELD (virtual_offset);
3662       mangle_call_offset (fixed_offset, virtual_offset);
3663       fn_decl = THUNK_TARGET (fn_decl);
3664     }
3665
3666   /* Scoped name.  */
3667   write_encoding (fn_decl);
3668
3669   result = finish_mangling_get_identifier (/*warn=*/false);
3670   if (DEBUG_MANGLE)
3671     fprintf (stderr, "mangle_thunk = %s\n\n", IDENTIFIER_POINTER (result));
3672   return result;
3673 }
3674
3675 /* This hash table maps TYPEs to the IDENTIFIER for a conversion
3676    operator to TYPE.  The nodes are IDENTIFIERs whose TREE_TYPE is the
3677    TYPE.  */
3678
3679 static GTY ((param_is (union tree_node))) htab_t conv_type_names;
3680
3681 /* Hash a node (VAL1) in the table.  */
3682
3683 static hashval_t
3684 hash_type (const void *val)
3685 {
3686   return (hashval_t) TYPE_UID (TREE_TYPE ((const_tree) val));
3687 }
3688
3689 /* Compare VAL1 (a node in the table) with VAL2 (a TYPE).  */
3690
3691 static int
3692 compare_type (const void *val1, const void *val2)
3693 {
3694   return TREE_TYPE ((const_tree) val1) == (const_tree) val2;
3695 }
3696
3697 /* Return an identifier for the mangled unqualified name for a
3698    conversion operator to TYPE.  This mangling is not specified by the
3699    ABI spec; it is only used internally.  */
3700
3701 tree
3702 mangle_conv_op_name_for_type (const tree type)
3703 {
3704   void **slot;
3705   tree identifier;
3706
3707   if (type == error_mark_node)
3708     return error_mark_node;
3709
3710   if (conv_type_names == NULL)
3711     conv_type_names = htab_create_ggc (31, &hash_type, &compare_type, NULL);
3712
3713   slot = htab_find_slot_with_hash (conv_type_names, type,
3714                                    (hashval_t) TYPE_UID (type), INSERT);
3715   identifier = (tree)*slot;
3716   if (!identifier)
3717     {
3718       char buffer[64];
3719
3720        /* Create a unique name corresponding to TYPE.  */
3721       sprintf (buffer, "operator %lu",
3722                (unsigned long) htab_elements (conv_type_names));
3723       identifier = get_identifier (buffer);
3724       *slot = identifier;
3725
3726       /* Hang TYPE off the identifier so it can be found easily later
3727          when performing conversions.  */
3728       TREE_TYPE (identifier) = type;
3729
3730       /* Set bits on the identifier so we know later it's a conversion.  */
3731       IDENTIFIER_OPNAME_P (identifier) = 1;
3732       IDENTIFIER_TYPENAME_P (identifier) = 1;
3733     }
3734
3735   return identifier;
3736 }
3737
3738 /* Write out the appropriate string for this variable when generating
3739    another mangled name based on this one.  */
3740
3741 static void
3742 write_guarded_var_name (const tree variable)
3743 {
3744   if (strncmp (IDENTIFIER_POINTER (DECL_NAME (variable)), "_ZGR", 4) == 0)
3745     /* The name of a guard variable for a reference temporary should refer
3746        to the reference, not the temporary.  */
3747     write_string (IDENTIFIER_POINTER (DECL_NAME (variable)) + 4);
3748   else
3749     write_name (variable, /*ignore_local_scope=*/0);
3750 }
3751
3752 /* Return an identifier for the name of an initialization guard
3753    variable for indicated VARIABLE.  */
3754
3755 tree
3756 mangle_guard_variable (const tree variable)
3757 {
3758   start_mangling (variable);
3759   write_string ("_ZGV");
3760   write_guarded_var_name (variable);
3761   return finish_mangling_get_identifier (/*warn=*/false);
3762 }
3763
3764 /* Return an identifier for the name of a thread_local initialization
3765    function for VARIABLE.  */
3766
3767 tree
3768 mangle_tls_init_fn (const tree variable)
3769 {
3770   start_mangling (variable);
3771   write_string ("_ZTH");
3772   write_guarded_var_name (variable);
3773   return finish_mangling_get_identifier (/*warn=*/false);
3774 }
3775
3776 /* Return an identifier for the name of a thread_local wrapper
3777    function for VARIABLE.  */
3778
3779 #define TLS_WRAPPER_PREFIX "_ZTW"
3780
3781 tree
3782 mangle_tls_wrapper_fn (const tree variable)
3783 {
3784   start_mangling (variable);
3785   write_string (TLS_WRAPPER_PREFIX);
3786   write_guarded_var_name (variable);
3787   return finish_mangling_get_identifier (/*warn=*/false);
3788 }
3789
3790 /* Return true iff FN is a thread_local wrapper function.  */
3791
3792 bool
3793 decl_tls_wrapper_p (const tree fn)
3794 {
3795   if (TREE_CODE (fn) != FUNCTION_DECL)
3796     return false;
3797   tree name = DECL_NAME (fn);
3798   return strncmp (IDENTIFIER_POINTER (name), TLS_WRAPPER_PREFIX,
3799                   strlen (TLS_WRAPPER_PREFIX)) == 0;
3800 }
3801
3802 /* Return an identifier for the name of a temporary variable used to
3803    initialize a static reference.  This isn't part of the ABI, but we might
3804    as well call them something readable.  */
3805
3806 static GTY(()) int temp_count;
3807
3808 tree
3809 mangle_ref_init_variable (const tree variable)
3810 {
3811   start_mangling (variable);
3812   write_string ("_ZGR");
3813   write_name (variable, /*ignore_local_scope=*/0);
3814   /* Avoid name clashes with aggregate initialization of multiple
3815      references at once.  */
3816   write_unsigned_number (temp_count++);
3817   return finish_mangling_get_identifier (/*warn=*/false);
3818 }
3819 \f
3820
3821 /* Foreign language type mangling section.  */
3822
3823 /* How to write the type codes for the integer Java type.  */
3824
3825 static void
3826 write_java_integer_type_codes (const tree type)
3827 {
3828   if (type == java_int_type_node)
3829     write_char ('i');
3830   else if (type == java_short_type_node)
3831     write_char ('s');
3832   else if (type == java_byte_type_node)
3833     write_char ('c');
3834   else if (type == java_char_type_node)
3835     write_char ('w');
3836   else if (type == java_long_type_node)
3837     write_char ('x');
3838   else if (type == java_boolean_type_node)
3839     write_char ('b');
3840   else
3841     gcc_unreachable ();
3842 }
3843
3844 #include "gt-cp-mangle.h"