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/* Some code common to C++ and ObjC++ front ends.

   Copyright (C) 2004 Free Software Foundation, Inc.

   Contributed by Ziemowit Laski  <zlaski@apple.com>

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 2, 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 COPYING.  If not, write to the Free

Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA

02110-1301, USA.  */

#include "config.h"

#include "system.h"

#include "coretypes.h"

#include "tm.h"

#include "tree.h"

#include "cp-tree.h"

#include "c-common.h"

#include "toplev.h"

#include "langhooks.h"

#include "langhooks-def.h"

#include "diagnostic.h"

#include "debug.h"

#include "cxx-pretty-print.h"

#include "cp-objcp-common.h"

/* Special routine to get the alias set for C++.  */

HOST_WIDE_INT

cxx_get_alias_set (tree t)

{

  if (IS_FAKE_BASE_TYPE (t))

    /* The base variant of a type must be in the same alias set as the

       complete type.  */

    return get_alias_set (TYPE_CONTEXT (t));

  /* Punt on PMFs until we canonicalize functions properly.  */

  if (TYPE_PTRMEMFUNC_P (t))

    return 0;

  return c_common_get_alias_set (t);

}

/* Called from check_global_declarations.  */

bool

cxx_warn_unused_global_decl (tree decl)

{

  if (TREE_CODE (decl) == FUNCTION_DECL && DECL_DECLARED_INLINE_P (decl))

    return false;

  if (DECL_IN_SYSTEM_HEADER (decl))

    return false;

  /* Const variables take the place of #defines in C++.  */

  if (TREE_CODE (decl) == VAR_DECL && TREE_READONLY (decl))

    return false;

  return true;

}

/* Langhook for expr_size: Tell the backend that the value of an expression

   of non-POD class type does not include any tail padding; a derived class

   might have allocated something there.  */

tree

cp_expr_size (tree exp)

{

  tree type = TREE_TYPE (exp);

  if (CLASS_TYPE_P (type))

    {

      /* The backend should not be interested in the size of an expression

         of a type with both of these set; all copies of such types must go

         through a constructor or assignment op.  */

      gcc_assert (!TYPE_HAS_COMPLEX_INIT_REF (type)

                  || !TYPE_HAS_COMPLEX_ASSIGN_REF (type)

                  /* But storing a CONSTRUCTOR isn't a copy.  */

                  || TREE_CODE (exp) == CONSTRUCTOR

                  /* And, the gimplifier will sometimes make a copy of

                     an aggregate.  In particular, for a case like:

                        struct S { S(); };

                        struct X { int a; S s; };

                        X x = { 0 };

                     the gimplifier will create a temporary with

                     static storage duration, perform static

                     initialization of the temporary, and then copy

                     the result.  Since the "s" subobject is never

                     constructed, this is a valid transformation.  */

                  || CP_AGGREGATE_TYPE_P (type));

      /* This would be wrong for a type with virtual bases, but they are

         caught by the assert above.  */

      return (is_empty_class (type)

              ? size_zero_node

              : CLASSTYPE_SIZE_UNIT (type));

    }

  else

    /* Use the default code.  */

    return lhd_expr_size (exp);

}

/* Langhook for tree_size: determine size of our 'x' and 'c' nodes.  */

size_t

cp_tree_size (enum tree_code code)

{

  switch (code)

    {

    case TINST_LEVEL:           return sizeof (struct tinst_level_s);

    case PTRMEM_CST:            return sizeof (struct ptrmem_cst);

    case BASELINK:              return sizeof (struct tree_baselink);

    case TEMPLATE_PARM_INDEX:   return sizeof (template_parm_index);

    case DEFAULT_ARG:           return sizeof (struct tree_default_arg);

    case OVERLOAD:              return sizeof (struct tree_overload);

    default:

      gcc_unreachable ();

    }

  /* NOTREACHED */

}

/* Returns true if T is a variably modified type, in the sense of C99.

   FN is as passed to variably_modified_p.

   This routine needs only check cases that cannot be handled by the

   language-independent logic in tree.c.  */

bool

cp_var_mod_type_p (tree type, tree fn)

{

  /* If TYPE is a pointer-to-member, it is variably modified if either

     the class or the member are variably modified.  */

  if (TYPE_PTR_TO_MEMBER_P (type))

    return (variably_modified_type_p (TYPE_PTRMEM_CLASS_TYPE (type), fn)

            || variably_modified_type_p (TYPE_PTRMEM_POINTED_TO_TYPE (type),

                                         fn));

  /* All other types are not variably modified.  */

  return false;

}

/* Construct a C++-aware pretty-printer for CONTEXT.  It is assumed

   that CONTEXT->printer is an already constructed basic pretty_printer.  */

void

cxx_initialize_diagnostics (diagnostic_context *context)

{

  pretty_printer *base = context->printer;

  cxx_pretty_printer *pp = xmalloc (sizeof (cxx_pretty_printer));

  memcpy (pp_base (pp), base, sizeof (pretty_printer));

  pp_cxx_pretty_printer_init (pp);

  context->printer = (pretty_printer *) pp;

  /* It is safe to free this object because it was previously malloc()'d.  */

  free (base);

}

/* 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

cxx_types_compatible_p (tree x, tree y)

{

  if (same_type_ignoring_top_level_qualifiers_p (x, y))

    return 1;

  /* Once we get to the middle-end, references and pointers are

     interchangeable.  FIXME should we try to replace all references with

     pointers?  */

  if (POINTER_TYPE_P (x) && POINTER_TYPE_P (y)

      && TYPE_MODE (x) == TYPE_MODE (y)

      && TYPE_REF_CAN_ALIAS_ALL (x) == TYPE_REF_CAN_ALIAS_ALL (y)

      && same_type_p (TREE_TYPE (x), TREE_TYPE (y)))

    return 1;

  return 0;

}

/* Stubs to keep c-opts.c happy.  */

void

push_file_scope (void)

{

}

void

pop_file_scope (void)

{

}

/* c-pragma.c needs to query whether a decl has extern "C" linkage.  */

bool

has_c_linkage (tree decl)

{

  return DECL_EXTERN_C_P (decl);

}

static GTY ((if_marked ("tree_map_marked_p"), param_is (struct tree_map)))

     htab_t shadowed_var_for_decl;

/* Lookup a shadowed var for FROM, and return it if we find one.  */

tree

decl_shadowed_for_var_lookup (tree from)

{

  struct tree_map *h, in;

  in.from = from;

  h = htab_find_with_hash (shadowed_var_for_decl, &in,

                           htab_hash_pointer (from));

  if (h)

    return h->to;

  return NULL_TREE;

}

/* Insert a mapping FROM->TO in the shadowed var hashtable.  */

void

decl_shadowed_for_var_insert (tree from, tree to)

{

  struct tree_map *h;

  void **loc;

  h = ggc_alloc (sizeof (struct tree_map));

  h->hash = htab_hash_pointer (from);

  h->from = from;

  h->to = to;

  loc = htab_find_slot_with_hash (shadowed_var_for_decl, h, h->hash, INSERT);

  *(struct tree_map **) loc = h;

}

void

init_shadowed_var_for_decl (void)

{

  shadowed_var_for_decl = htab_create_ggc (512, tree_map_hash,

                                           tree_map_eq, 0);

}

#include "gt-cp-cp-objcp-common.h"