text: /* Modula-3: modified */
  
  /* The lang_hooks data structure.
     Copyright 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009
     Free Software Foundation, Inc.
  
  This file is part of GCC.
  
  GCC is free software; you can redistribute it and/or modify
  it under the terms of the GNU General Public License as published by
  the Free Software Foundation; either version 3, or (at your option)
  any later version.
  
  GCC is distributed in the hope that it will be useful,
  but WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  GNU General Public License for more details.
  
  You should have received a copy of the GNU General Public License
  along with GCC; see the file COPYING3.  If not see
  <http://www.gnu.org/licenses/>.  */
  
  #ifndef GCC_LANG_HOOKS_H
  #define GCC_LANG_HOOKS_H
  
  #ifdef __cplusplus
  extern "C" {
  #endif
  
  /* This file should be #include-d after tree.h.  */
  
  struct diagnostic_context;
  struct diagnostic_info;
  
  struct gimplify_omp_ctx;
  
  struct array_descr_info;
  
  /* A print hook for print_tree ().  */
  typedef void (*lang_print_tree_hook) (FILE *, tree, int indent);
  
  enum classify_record
    { RECORD_IS_STRUCT, RECORD_IS_CLASS, RECORD_IS_INTERFACE };
  
  /* The following hooks are documented in langhooks.c.  Must not be
     NULL.  */
  
  struct lang_hooks_for_tree_inlining
  {
    bool (*var_mod_type_p) (tree, tree);
  };
  
  struct lang_hooks_for_callgraph
  {
    /* The node passed is a language-specific tree node.  If its contents
       are relevant to use of other declarations, mark them.  */
    tree (*analyze_expr) (tree *, int *);
  };
  
  /* The following hooks are used by tree-dump.c.  */
  
  struct lang_hooks_for_tree_dump
  {
    /* Dump language-specific parts of tree nodes.  Returns nonzero if it
       does not want the usual dumping of the second argument.  */
    bool (*dump_tree) (void *, tree);
  
    /* Determine type qualifiers in a language-specific way.  */
    int (*type_quals) (const_tree);
  };
  
  /* Hooks related to types.  */
  
  struct lang_hooks_for_types
  {
    /* Return a new type (with the indicated CODE), doing whatever
       language-specific processing is required.  */
    tree (*make_type) (enum tree_code);
  
    /* Return what kind of RECORD_TYPE this is, mainly for purposes of
       debug information.  If not defined, record types are assumed to
       be structures.  */
    enum classify_record (*classify_record) (tree);
  
    /* Given MODE and UNSIGNEDP, return a suitable type-tree with that
       mode.  */
    tree (*type_for_mode) (enum machine_mode, int);
  
    /* Given PRECISION and UNSIGNEDP, return a suitable type-tree for an
       integer type with at least that precision.  */
    tree (*type_for_size) (unsigned, int);
  
    /* True if the type is an instantiation of a generic type,
       e.g. C++ template implicit specializations.  */
    bool (*generic_p) (const_tree);
  
    /* Returns the TREE_VEC of elements of a given generic argument pack.  */
    tree (*get_argument_pack_elems) (const_tree);
  
    /* Given a type, apply default promotions to unnamed function
       arguments and return the new type.  Return the same type if no
       change.  Required by any language that supports variadic
       arguments.  The default hook dies.  */
    tree (*type_promotes_to) (tree);
  
    /* Register TYPE as a builtin type with the indicated NAME.  The
       TYPE is placed in the outermost lexical scope.  The semantics
       should be analogous to:
  
         typedef TYPE NAME;
  
       in C.  The default hook ignores the declaration.  */
    void (*register_builtin_type) (tree, const char *);
  
    /* This routine is called in tree.c to print an error message for
       invalid use of an incomplete type.  VALUE is the expression that
       was used (or 0 if that isn't known) and TYPE is the type that was
       invalid.  */
    void (*incomplete_type_error) (const_tree value, const_tree type);
  
    /* Called from assign_temp to return the maximum size, if there is one,
       for a type.  */
    tree (*max_size) (const_tree);
  
    /* Register language specific type size variables as potentially OpenMP
       firstprivate variables.  */
    void (*omp_firstprivatize_type_sizes) (struct gimplify_omp_ctx *, tree);
  
    /* Return TRUE if TYPE1 and TYPE2 are identical for type hashing purposes.
       Called only after doing all language independent checks.
       At present, this function is only called when both TYPE1 and TYPE2 are
       FUNCTION_TYPEs.  */
    bool (*type_hash_eq) (const_tree, const_tree);
  
    /* Return TRUE if TYPE uses a hidden descriptor and fills in information
       for the debugger about the array bounds, strides, etc.  */
    bool (*get_array_descr_info) (const_tree, struct array_descr_info *);
  
    /* Fill in information for the debugger about the bounds of TYPE.  */
    void (*get_subrange_bounds) (const_tree, tree *, tree *);
  
    /* If we requested a pointer to a vector, build up the pointers that
       we stripped off while looking for the inner type.  Similarly for
       return values from functions.  The argument TYPE is the top of the
       chain, and BOTTOM is the new type which we will point to.  */
    tree (*reconstruct_complex_type) (tree, tree);
  
    /* Nonzero if types that are identical are to be hashed so that only
       one copy is kept.  If a language requires unique types for each
       user-specified type, such as Ada, this should be set to TRUE.  */
    bool hash_types;
  };
  
  /* Language hooks related to decls and the symbol table.  */
  
  struct lang_hooks_for_decls
  {
    /* Return true if we are in the global binding level.  This hook is really
       needed only if the language supports variable-sized types at the global
       level, i.e. declared outside subprograms.  */
    bool (*global_bindings_p) (void);
  
    /* Function to add a decl to the current scope level.  Takes one
       argument, a decl to add.  Returns that decl, or, if the same
       symbol is already declared, may return a different decl for that
       name.  */
    tree (*pushdecl) (tree);
  
    /* Returns the chain of decls so far in the current scope level.  */
    tree (*getdecls) (void);
  
    /* Returns true if DECL is explicit member function.  */
    bool (*function_decl_explicit_p) (tree);
  
    /* Returns True if the parameter is a generic parameter decl
       of a generic type, e.g a template template parameter for the C++ FE.  */
    bool (*generic_generic_parameter_decl_p) (const_tree);
  
    /* Determine if a function parameter got expanded from a
       function parameter pack.  */
    bool (*function_parm_expanded_from_pack_p) (tree, tree);
  
    /* Returns the generic declaration of a generic function instantiations.  */
    tree (*get_generic_function_decl) (const_tree);
  
    /* Returns true when we should warn for an unused global DECL.
       We will already have checked that it has static binding.  */
    bool (*warn_unused_global) (const_tree);
  
    /* Obtain a list of globals and do final output on them at end
       of compilation */
    void (*final_write_globals) (void);
  
    /* True if this decl may be called via a sibcall.  */
    bool (*ok_for_sibcall) (const_tree);
  
    /* True if OpenMP should privatize what this DECL points to rather
       than the DECL itself.  */
    bool (*omp_privatize_by_reference) (const_tree);
  
    /* Return sharing kind if OpenMP sharing attribute of DECL is
       predetermined, OMP_CLAUSE_DEFAULT_UNSPECIFIED otherwise.  */
    enum omp_clause_default_kind (*omp_predetermined_sharing) (tree);
  
    /* Return decl that should be reported for DEFAULT(NONE) failure
       diagnostics.  Usually the DECL passed in.  */
    tree (*omp_report_decl) (tree);
  
    /* Return true if DECL's DECL_VALUE_EXPR (if any) should be
       disregarded in OpenMP construct, because it is going to be
       remapped during OpenMP lowering.  SHARED is true if DECL
       is going to be shared, false if it is going to be privatized.  */
    bool (*omp_disregard_value_expr) (tree, bool);
  
    /* Return true if DECL that is shared iff SHARED is true should
       be put into OMP_CLAUSE_PRIVATE_DEBUG.  */
    bool (*omp_private_debug_clause) (tree, bool);
  
    /* Return true if DECL in private clause needs
       OMP_CLAUSE_PRIVATE_OUTER_REF on the private clause.  */
    bool (*omp_private_outer_ref) (tree);
  
    /* Build and return code for a default constructor for DECL in
       response to CLAUSE.  OUTER is corresponding outer region's
       variable if needed.  Return NULL if nothing to be done.  */
    tree (*omp_clause_default_ctor) (tree clause, tree decl, tree outer);
  
    /* Build and return code for a copy constructor from SRC to DST.  */
    tree (*omp_clause_copy_ctor) (tree clause, tree dst, tree src);
  
    /* Similarly, except use an assignment operator instead.  */
    tree (*omp_clause_assign_op) (tree clause, tree dst, tree src);
  
    /* Build and return code destructing DECL.  Return NULL if nothing
       to be done.  */
    tree (*omp_clause_dtor) (tree clause, tree decl);
  
    /* Do language specific checking on an implicitly determined clause.  */
    void (*omp_finish_clause) (tree clause);
  };
  
  /* Language hooks related to LTO serialization.  */
  
  struct lang_hooks_for_lto
  {
    /* Begin a new LTO section named NAME.  */
    void (*begin_section) (const char *name);
  
    /* Write DATA of length LEN to the currently open LTO section.  BLOCK is a
       pointer to the dynamically allocated memory containing DATA.  The
       append_data function is responsible for freeing it when it is no longer
       needed.  */
    void (*append_data) (const void *data, size_t len, void *block);
  
    /* End the previously begun LTO section.  */
    void (*end_section) (void);
  };
  
  /* Language-specific hooks.  See langhooks-def.h for defaults.  */
  
  struct lang_hooks
  {
    /* String identifying the front end.  e.g. "GNU C++".  */
    const char *name;
  
    /* sizeof (struct lang_identifier), so make_node () creates
       identifier nodes long enough for the language-specific slots.  */
    size_t identifier_size;
  
    /* Remove any parts of the tree that are used only by the FE. */
    void (*free_lang_data) (tree);
  
    /* Determines the size of any language-specific tcc_constant or
       tcc_exceptional nodes.  Since it is called from make_node, the
       only information available is the tree code.  Expected to die
       on unrecognized codes.  */
    size_t (*tree_size) (enum tree_code);
  
    /* The first callback made to the front end, for simple
       initialization needed before any calls to handle_option.  Return
       the language mask to filter the switch array with.  */
    unsigned int (*init_options) (unsigned int argc, const char **argv);
  
    /* Callback used to perform language-specific initialization for the
       global diagnostic context structure.  */
    void (*initialize_diagnostics) (struct diagnostic_context *);
  
    /* Handle the switch CODE, which has real type enum opt_code from
       options.h.  If the switch takes an argument, it is passed in ARG
       which points to permanent storage.  The handler is responsible for
       checking whether ARG is NULL, which indicates that no argument
       was in fact supplied.  For -f and -W switches, VALUE is 1 or 0
       for the positive and negative forms respectively.
  
       Return 1 if the switch is valid, 0 if invalid, and -1 if it's
       valid and should not be treated as language-independent too.  */
    int (*handle_option) (size_t code, const char *arg, int value);
  
    /* Return false to use the default complaint about a missing
       argument, otherwise output a complaint and return true.  */
    bool (*missing_argument) (const char *opt, size_t code);
  
    /* Called when all command line options have been parsed to allow
       further processing and initialization
  
       Should return true to indicate that a compiler back-end is
       not required, such as with the -E option.
  
       If errorcount is nonzero after this call the compiler exits
       immediately and the finish hook is not called.  */
    bool (*post_options) (const char **);
  
    /* Called after post_options to initialize the front end.  Return
       false to indicate that no further compilation be performed, in
       which case the finish hook is called immediately.  */
    bool (*init) (void);
  
    /* Called at the end of compilation, as a finalizer.  */
    void (*finish) (void);
  
    /* Parses the entire file.  The argument is nonzero to cause bison
       parsers to dump debugging information during parsing.  */
    void (*parse_file) (int);
  
    /* Determines if it's ok for a function to have no noreturn attribute.  */
    bool (*missing_noreturn_ok_p) (tree);
  
    /* Called to obtain the alias set to be used for an expression or type.
       Returns -1 if the language does nothing special for it.  */
    alias_set_type (*get_alias_set) (tree);
  
    /* Function to finish handling an incomplete decl at the end of
       compilation.  Default hook is does nothing.  */
    void (*finish_incomplete_decl) (tree);
  
    /* Replace the DECL_LANG_SPECIFIC data, which may be NULL, of the
       DECL_NODE with a newly GC-allocated copy.  */
    void (*dup_lang_specific_decl) (tree);
  
    /* Set the DECL_ASSEMBLER_NAME for a node.  If it is the sort of
       thing that the assembler should talk about, set
       DECL_ASSEMBLER_NAME to an appropriate IDENTIFIER_NODE.
       Otherwise, set it to the ERROR_MARK_NODE to ensure that the
       assembler does not talk about it.  */
    void (*set_decl_assembler_name) (tree);
  
    /* The front end can add its own statistics to -fmem-report with
       this hook.  It should output to stderr.  */
    void (*print_statistics) (void);
  
    /* Called by print_tree when there is a tree of class tcc_exceptional
       that it doesn't know how to display.  */
    lang_print_tree_hook print_xnode;
  
    /* Called to print language-dependent parts of tcc_decl, tcc_type,
       and IDENTIFIER_NODE nodes.  */
    lang_print_tree_hook print_decl;
    lang_print_tree_hook print_type;
    lang_print_tree_hook print_identifier;
  
    /* Computes the name to use to print a declaration.  DECL is the
       non-NULL declaration in question.  VERBOSITY determines what
       information will be printed: 0: DECL_NAME, demangled as
       necessary.  1: and scope information.  2: and any other
       information that might be interesting, such as function parameter
       types in C++.  The name is in the internal character set and
       needs to be converted to the locale character set of diagnostics,
       or to the execution character set for strings such as
       __PRETTY_FUNCTION__.  */
    const char *(*decl_printable_name) (tree decl, int verbosity);
  
    /* Computes the dwarf-2/3 name for a tree.  VERBOSITY determines what
       information will be printed: 0: DECL_NAME, demangled as
       necessary.  1: and scope information.  */
    const char *(*dwarf_name) (tree, int verbosity);
  
    /* This compares two types for equivalence ("compatible" in C-based languages).
       This routine should only return 1 if it is sure.  It should not be used
       in contexts where erroneously returning 0 causes problems.  */
    int (*types_compatible_p) (tree x, tree y);
  
    /* Called by report_error_function to print out function name.  */
    void (*print_error_function) (struct diagnostic_context *, const char *,
  				struct diagnostic_info *);
  
    /* Convert a character from the host's to the target's character
       set.  The character should be in what C calls the "basic source
       character set" (roughly, the set of characters defined by plain
       old ASCII).  The default is to return the character unchanged,
       which is correct in most circumstances.  Note that both argument
       and result should be sign-extended under -fsigned-char,
       zero-extended under -fno-signed-char.  */
    HOST_WIDE_INT (*to_target_charset) (HOST_WIDE_INT);
  
    /* Pointers to machine-independent attribute tables, for front ends
       using attribs.c.  If one is NULL, it is ignored.  Respectively, a
       table of attributes specific to the language, a table of
       attributes common to two or more languages (to allow easy
       sharing), and a table of attributes for checking formats.  */
    const struct attribute_spec *attribute_table;
    const struct attribute_spec *common_attribute_table;
    const struct attribute_spec *format_attribute_table;
  
    struct lang_hooks_for_tree_inlining tree_inlining;
  
    struct lang_hooks_for_callgraph callgraph;
  
    struct lang_hooks_for_tree_dump tree_dump;
  
    struct lang_hooks_for_decls decls;
  
    struct lang_hooks_for_types types;
  
    struct lang_hooks_for_lto lto;
  
    /* Returns the generic parameters of an instantiation of
       a generic type or decl, e.g. C++ template instantiation.  */
    tree (*get_innermost_generic_parms) (const_tree);
  
    /* Returns the TREE_VEC of arguments of an instantiation
       of a generic type of decl, e.g. C++ template instantiation.  */
    tree (*get_innermost_generic_args) (const_tree);
  
    /* Determine if a tree is a function parameter pack.  */
    bool (*function_parameter_pack_p) (const_tree);
  
    /* Perform language-specific gimplification on the argument.  Returns an
       enum gimplify_status, though we can't see that type here.  */
    int (*gimplify_expr) (tree *, gimple_seq *, gimple_seq *);
  
    /* Fold an OBJ_TYPE_REF expression to the address of a function.
       KNOWN_TYPE carries the true type of the OBJ_TYPE_REF_OBJECT.  */
    tree (*fold_obj_type_ref) (tree, tree);
  
    /* Do language specific processing in the builtin function DECL  */
    tree (*builtin_function) (tree decl);
  
    /* Like builtin_function, but make sure the scope is the external scope.
       This is used to delay putting in back end builtin functions until the ISA
       that defines the builtin is declared via function specific target options,
       which can save memory for machines like the x86_64 that have multiple
       ISAs.  If this points to the same function as builtin_function, the
       backend must add all of the builtins at program initialization time.  */
    tree (*builtin_function_ext_scope) (tree decl);
  
    /* Used to set up the tree_contains_structure array for a frontend. */
    void (*init_ts) (void);
  
    /* Called by recompute_tree_invariant_for_addr_expr to go from EXPR
       to a contained expression or DECL, possibly updating *TC or *SE
       if in the process TREE_CONSTANT or TREE_SIDE_EFFECTS need updating.  */
    tree (*expr_to_decl) (tree expr, bool *tc, bool *se);
  
    /* The EH personality function decl.  */
    tree (*eh_personality) (void);
  
    /* Map a type to a runtime object to match type.  */
    tree (*eh_runtime_type) (tree);
  
    /* True if this language uses __cxa_end_cleanup when the ARM EABI
       is enabled.  */
    bool eh_use_cxa_end_cleanup;
  
    /* Whenever you add entries here, make sure you adjust langhooks-def.h
       and langhooks.c accordingly.  */
  };
  
  /* Each front end provides its own.  */
  extern struct lang_hooks lang_hooks;
  extern tree add_builtin_function (const char *name, tree type,
  				  int function_code, enum built_in_class cl,
  				  const char *library_name,
  				  tree attrs);
  
  extern tree add_builtin_function_ext_scope (const char *name, tree type,
  					    int function_code,
  					    enum built_in_class cl,
  					    const char *library_name,
  					    tree attrs);
  
  #ifdef __cplusplus
  } /* extern "C" */
  #endif
  
  #endif /* GCC_LANG_HOOKS_H */
  