Let GDB reuse GCC's parser.

2014-10-27  Phil Muldoon  <pmuldoon@redhat.com>
	    Jan Kratochvil  <jan.kratochvil@redhat.com>
	    Tom Tromey  <tromey@redhat.com>

	* aclocal.m4: New file.
	* callbacks.cc: New file.
	* callbacks.hh: New file.
	* cc1plugin-config.h.in: New file.
	* configure: New file.
	* configure.ac: New file.
	* connection.cc: New file.
	* connection.hh: New file.
	* findcomp.cc: New file.
	* findcomp.hh: New file.
	* libcc1.cc: New file.
	* libcc1plugin.sym: New file.
	* libcc1.sym: New file.
	* Makefile.am: New file.
	* Makefile.in: New file.
	* marshall.cc: New file.
	* marshall.hh: New file.
	* names.cc: New file.
	* names.hh: New file.
	* plugin.cc: New file.
	* rpc.hh: New file.
	* status.hh: New file.

2014-10-27  Phil Muldoon  <pmuldoon@redhat.com>
	    Jan Kratochvil  <jan.kratochvil@redhat.com>
	    Tom Tromey  <tromey@redhat.com>

	* gcc-c-fe.def: New file.
	* gcc-c-interface.h: New file.
	* gcc-interface.h: New file.

2014-10-27  Phil Muldoon  <pmuldoon@redhat.com>
	    Tom Tromey  <tromey@redhat.com>

	* c-tree.h (enum c_oracle_request): New.
	(c_binding_oracle_function): New typedef.
	(c_binding_oracle, c_pushtag, c_bind): Declare.
	* c-decl.c (c_binding_oracle): New global.
	(I_SYMBOL_CHECKED): New macro.
	(i_symbol_binding): New function.
	(I_SYMBOL_BINDING, I_SYMBOL_DECL): Redefine.
	(I_TAG_CHECKED): New macro.
	(i_tag_binding): New function.
	(I_TAG_BINDING, I_TAG_DECL): Redefine.
	(I_LABEL_CHECKED): New macro.
	(i_label_binding): New function.
	(I_LABEL_BINDING, I_LABEL_DECL): Redefine.
	(c_print_identifier): Save and restore c_binding_oracle.
	(c_pushtag, c_bind): New functions.

2014-10-27  Phil Muldoon  <pmuldoon@redhat.com>
	    Tom Tromey  <tromey@redhat.com>

	* aclocal.m4, configure: Rebuild.
	* Makefile.in (aclocal_deps): Add gcc-plugin.m4.
	* configure.ac: Use GCC_ENABLE_PLUGINS.
	* stor-layout.c (finish_bitfield_layout): Now public.  Change
	argument type to 'tree'.
	(finish_record_layout): Update.
	* stor-layout.h (finish_bitfield_layout): Declare.

2014-10-27  Tom Tromey  <tromey@redhat.com>

	* gcc-plugin.m4: New file.

2014-10-27  Phil Muldoon  <pmuldoon@redhat.com>
	    Tom Tromey  <tromey@redhat.com>

	* Makefile.def: Add libcc1 to host_modules.
	* configure.ac (host_tools): Add libcc1.
	* Makefile.in, configure: Rebuild.




git-svn-id: https://gcc.gnu.org/svn/gcc/trunk@216748 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 916 insertions, 0 deletions

diff --git a/libcc1/plugin.cc b/libcc1/plugin.cc
new file mode 100644
index 00000000000..5cdd19d78ce
--- /dev/null
+++ b/libcc1/plugin.cc
@@ -0,0 +1,916 @@
+/* Library interface to C front end
+   Copyright (C) 2014 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/>.  */
+
+#include <cc1plugin-config.h>
+
+#undef PACKAGE_NAME
+#undef PACKAGE_STRING
+#undef PACKAGE_TARNAME
+#undef PACKAGE_VERSION
+
+#include "../gcc/config.h"
+
+#undef PACKAGE_NAME
+#undef PACKAGE_STRING
+#undef PACKAGE_TARNAME
+#undef PACKAGE_VERSION
+
+#include "gcc-plugin.h"
+#include "system.h"
+#include "coretypes.h"
+#include "stringpool.h"
+
+#include "gcc-interface.h"
+#include "tree-core.h"
+#include "wide-int.h"
+#include "stor-layout.h"
+#include "c-tree.h"
+#include "toplev.h"
+#include "timevar.h"
+#include "hash-table.h"
+#include "tm.h"
+#include "c-family/c-pragma.h"
+#include "c-lang.h"
+#include "diagnostic.h"
+#include "langhooks.h"
+#include "langhooks-def.h"
+
+#include "callbacks.hh"
+#include "connection.hh"
+#include "rpc.hh"
+
+#include <string>
+
+#ifdef __GNUC__
+#pragma GCC visibility push(default)
+#endif
+int plugin_is_GPL_compatible;
+#ifdef __GNUC__
+#pragma GCC visibility pop
+#endif
+
+
+
+// This is put into the lang hooks when the plugin starts.
+
+static void
+plugin_print_error_function (diagnostic_context *context, const char *file,
+			     diagnostic_info *diagnostic)
+{
+  if (current_function_decl != NULL_TREE
+      && DECL_NAME (current_function_decl) != NULL_TREE
+      && strcmp (IDENTIFIER_POINTER (DECL_NAME (current_function_decl)),
+		 GCC_FE_WRAPPER_FUNCTION) == 0)
+    return;
+  lhd_print_error_function (context, file, diagnostic);
+}
+
+
+
+static unsigned long long
+convert_out (tree t)
+{
+  return (unsigned long long) (uintptr_t) t;
+}
+
+static tree
+convert_in (unsigned long long v)
+{
+  return (tree) (uintptr_t) v;
+}
+
+
+
+struct decl_addr_value
+{
+  tree decl;
+  tree address;
+};
+
+struct decl_addr_hasher : typed_free_remove<decl_addr_value>
+{
+  typedef decl_addr_value value_type;
+  typedef decl_addr_value compare_type;
+
+  static inline hashval_t hash (const value_type *);
+  static inline bool equal (const value_type *, const compare_type *);
+};
+
+inline hashval_t
+decl_addr_hasher::hash (const value_type *e)
+{
+  return IDENTIFIER_HASH_VALUE (DECL_NAME (e->decl));
+}
+
+inline bool
+decl_addr_hasher::equal (const value_type *p1, const compare_type *p2)
+{
+  return p1->decl == p2->decl;
+}
+
+
+
+struct string_hasher : typed_noop_remove<char>
+{
+  typedef char value_type;
+  typedef char compare_type;
+
+  static inline hashval_t hash (const value_type *s)
+  {
+    return htab_hash_string (s);
+  }
+
+  static inline bool equal (const value_type *p1, const value_type *p2)
+  {
+    return strcmp (p1, p2) == 0;
+  }
+};
+
+
+
+// A wrapper for pushdecl that doesn't let gdb have a chance to
+// instantiate a symbol.
+
+static void
+pushdecl_safe (tree decl)
+{
+  void (*save) (enum c_oracle_request, tree identifier);
+
+  save = c_binding_oracle;
+  c_binding_oracle = NULL;
+  pushdecl (decl);
+  c_binding_oracle = save;
+}
+
+
+
+struct plugin_context : public cc1_plugin::connection
+{
+  plugin_context (int fd);
+
+  // Map decls to addresses.
+  hash_table<decl_addr_hasher> address_map;
+
+  // A collection of trees that are preserved for the GC.
+  hash_table< pointer_hash<tree_node> > preserved;
+
+  // File name cache.
+  hash_table<string_hasher> file_names;
+
+  // Perform GC marking.
+  void mark ();
+
+  // Preserve a tree during the plugin's operation.
+  tree preserve (tree t)
+  {
+    tree_node **slot = preserved.find_slot (t, INSERT);
+    *slot = t;
+    return t;
+  }
+
+  source_location get_source_location (const char *filename,
+				       unsigned int line_number)
+  {
+    if (filename == NULL)
+      return UNKNOWN_LOCATION;
+
+    filename = intern_filename (filename);
+    linemap_add (line_table, LC_ENTER, false, filename, line_number);
+    source_location loc = linemap_line_start (line_table, line_number, 0);
+    linemap_add (line_table, LC_LEAVE, false, NULL, 0);
+    return loc;
+  }
+
+private:
+
+  // Add a file name to FILE_NAMES and return the canonical copy.
+  const char *intern_filename (const char *filename)
+  {
+    char **slot = file_names.find_slot (filename, INSERT);
+    if (*slot == NULL)
+      {
+	/* The file name must live as long as the line map, which
+	   effectively means as long as this compilation.  So, we copy
+	   the string here but never free it.  */
+	*slot = xstrdup (filename);
+      }
+    return *slot;
+  }
+};
+
+static plugin_context *current_context;
+
+
+
+plugin_context::plugin_context (int fd)
+  : cc1_plugin::connection (fd),
+    address_map (30),
+    preserved (30),
+    file_names (30)
+{
+}
+
+void
+plugin_context::mark ()
+{
+  for (hash_table<decl_addr_hasher>::iterator it = address_map.begin ();
+       it != address_map.end ();
+       ++it)
+    {
+      ggc_mark ((*it)->decl);
+      ggc_mark ((*it)->address);
+    }
+
+  for (hash_table< pointer_hash<tree_node> >::iterator it = preserved.begin ();
+       it != preserved.end ();
+       ++it)
+    ggc_mark (&*it);
+}
+
+static void
+plugin_binding_oracle (enum c_oracle_request kind, tree identifier)
+{
+  enum gcc_c_oracle_request request;
+
+  gcc_assert (current_context != NULL);
+
+  switch (kind)
+    {
+    case C_ORACLE_SYMBOL:
+      request = GCC_C_ORACLE_SYMBOL;
+      break;
+    case C_ORACLE_TAG:
+      request = GCC_C_ORACLE_TAG;
+      break;
+    case C_ORACLE_LABEL:
+      request = GCC_C_ORACLE_LABEL;
+      break;
+    default:
+      abort ();
+    }
+
+  int ignore;
+  cc1_plugin::call (current_context, "binding_oracle", &ignore,
+		    request, IDENTIFIER_POINTER (identifier));
+}
+
+static void
+plugin_pragma_user_expression (cpp_reader *)
+{
+  c_binding_oracle = plugin_binding_oracle;
+}
+
+static void
+plugin_init_extra_pragmas (void *, void *)
+{
+  c_register_pragma ("GCC", "user_expression", plugin_pragma_user_expression);
+}
+
+
+
+// Maybe rewrite a decl to its address.
+static tree
+address_rewriter (tree *in, int *walk_subtrees, void *arg)
+{
+  plugin_context *ctx = (plugin_context *) arg;
+
+  if (!DECL_P (*in) || DECL_NAME (*in) == NULL_TREE)
+    return NULL_TREE;
+
+  decl_addr_value value;
+  value.decl = *in;
+  decl_addr_value *found_value = ctx->address_map.find (&value);
+  if (found_value != NULL)
+    {
+      // At this point we don't need VLA sizes for gdb-supplied
+      // variables, and having them here confuses later passes, so we
+      // drop them.
+      if (C_TYPE_VARIABLE_SIZE (TREE_TYPE (*in)))
+	{
+	  TREE_TYPE (*in)
+	    = build_array_type_nelts (TREE_TYPE (TREE_TYPE (*in)), 1);
+	  DECL_SIZE (*in) = TYPE_SIZE (TREE_TYPE (*in));
+	  DECL_SIZE_UNIT (*in) = TYPE_SIZE_UNIT (TREE_TYPE (*in));
+	}
+    }
+  else if (DECL_IS_BUILTIN (*in))
+    {
+      gcc_address address;
+
+      if (!cc1_plugin::call (ctx, "address_oracle", &address,
+			     IDENTIFIER_POINTER (DECL_NAME (*in))))
+	return NULL_TREE;
+      if (address == 0)
+	return NULL_TREE;
+
+      // Insert the decl into the address map in case it is referenced
+      // again.
+      value.address = build_int_cst_type (ptr_type_node, address);
+      decl_addr_value **slot = ctx->address_map.find_slot (&value, INSERT);
+      gcc_assert (*slot == NULL);
+      *slot
+	= static_cast<decl_addr_value *> (xmalloc (sizeof (decl_addr_value)));
+      **slot = value;
+      found_value = *slot;
+    }
+  else
+    return NULL_TREE;
+
+  if (found_value->address != error_mark_node)
+    {
+      // We have an address for the decl, so rewrite the tree.
+      tree ptr_type = build_pointer_type (TREE_TYPE (*in));
+      *in = fold_build1 (INDIRECT_REF, TREE_TYPE (*in),
+			 fold_build1 (CONVERT_EXPR, ptr_type,
+				      found_value->address));
+    }
+
+  *walk_subtrees = 0;
+
+  return NULL_TREE;
+}
+
+// When generating code for gdb, we want to be able to use absolute
+// addresses to refer to otherwise external objects that gdb knows
+// about.  gdb passes in these addresses when building decls, and then
+// before gimplification we go through the trees, rewriting uses to
+// the equivalent of "*(TYPE *) ADDR".
+static void
+rewrite_decls_to_addresses (void *function_in, void *)
+{
+  tree function = (tree) function_in;
+
+  // Do nothing if we're not in gdb.
+  if (current_context == NULL)
+    return;
+
+  walk_tree (&DECL_SAVED_TREE (function), address_rewriter, current_context,
+	     NULL);
+}
+
+
+
+gcc_decl
+plugin_build_decl (cc1_plugin::connection *self,
+		   const char *name,
+		   enum gcc_c_symbol_kind sym_kind,
+		   gcc_type sym_type_in,
+		   const char *substitution_name,
+		   gcc_address address,
+		   const char *filename,
+		   unsigned int line_number)
+{
+  plugin_context *ctx = static_cast<plugin_context *> (self);
+  tree identifier = get_identifier (name);
+  enum tree_code code;
+  tree decl;
+  tree sym_type = convert_in (sym_type_in);
+
+  switch (sym_kind)
+    {
+    case GCC_C_SYMBOL_FUNCTION:
+      code = FUNCTION_DECL;
+      break;
+
+    case GCC_C_SYMBOL_VARIABLE:
+      code = VAR_DECL;
+      break;
+
+    case GCC_C_SYMBOL_TYPEDEF:
+      code = TYPE_DECL;
+      break;
+
+    case GCC_C_SYMBOL_LABEL:
+      // FIXME: we aren't ready to handle labels yet.
+      // It isn't clear how to translate them properly
+      // and in any case a "goto" isn't likely to work.
+      return convert_out (error_mark_node);
+
+    default:
+      abort ();
+    }
+
+  source_location loc = ctx->get_source_location (filename, line_number);
+
+  decl = build_decl (loc, code, identifier, sym_type);
+  TREE_USED (decl) = 1;
+  TREE_ADDRESSABLE (decl) = 1;
+
+  if (sym_kind != GCC_C_SYMBOL_TYPEDEF)
+    {
+      decl_addr_value value;
+
+      value.decl = decl;
+      if (substitution_name != NULL)
+	{
+	  // If the translator gave us a name without a binding,
+	  // we can just substitute error_mark_node, since we know the
+	  // translator will be reporting an error anyhow.
+	  value.address
+	    = lookup_name (get_identifier (substitution_name));
+	  if (value.address == NULL_TREE)
+	    value.address = error_mark_node;
+	}
+      else
+	value.address = build_int_cst_type (ptr_type_node, address);
+      decl_addr_value **slot = ctx->address_map.find_slot (&value, INSERT);
+      gcc_assert (*slot == NULL);
+      *slot
+	= static_cast<decl_addr_value *> (xmalloc (sizeof (decl_addr_value)));
+      **slot = value;
+    }
+
+  return convert_out (ctx->preserve (decl));
+}
+
+int
+plugin_bind (cc1_plugin::connection *,
+	     gcc_decl decl_in, int is_global)
+{
+  tree decl = convert_in (decl_in);
+  c_bind (DECL_SOURCE_LOCATION (decl), decl, is_global);
+  rest_of_decl_compilation (decl, is_global, 0);
+  return 1;
+}
+
+int
+plugin_tagbind (cc1_plugin::connection *self,
+		const char *name, gcc_type tagged_type,
+		const char *filename, unsigned int line_number)
+{
+  plugin_context *ctx = static_cast<plugin_context *> (self);
+  c_pushtag (ctx->get_source_location (filename, line_number),
+	     get_identifier (name), convert_in (tagged_type));
+  return 1;
+}
+
+gcc_type
+plugin_build_pointer_type (cc1_plugin::connection *,
+			   gcc_type base_type)
+{
+  // No need to preserve a pointer type as the base type is preserved.
+  return convert_out (build_pointer_type (convert_in (base_type)));
+}
+
+gcc_type
+plugin_build_record_type (cc1_plugin::connection *self)
+{
+  plugin_context *ctx = static_cast<plugin_context *> (self);
+  return convert_out (ctx->preserve (make_node (RECORD_TYPE)));
+}
+
+gcc_type
+plugin_build_union_type (cc1_plugin::connection *self)
+{
+  plugin_context *ctx = static_cast<plugin_context *> (self);
+  return convert_out (ctx->preserve (make_node (UNION_TYPE)));
+}
+
+int
+plugin_build_add_field (cc1_plugin::connection *,
+			gcc_type record_or_union_type_in,
+			const char *field_name,
+			gcc_type field_type_in,
+			unsigned long bitsize,
+			unsigned long bitpos)
+{
+  tree record_or_union_type = convert_in (record_or_union_type_in);
+  tree field_type = convert_in (field_type_in);
+
+  gcc_assert (TREE_CODE (record_or_union_type) == RECORD_TYPE
+	      || TREE_CODE (record_or_union_type) == UNION_TYPE);
+
+  /* Note that gdb does not preserve the location of field decls, so
+     we can't provide a decent location here.  */
+  tree decl = build_decl (BUILTINS_LOCATION, FIELD_DECL,
+			  get_identifier (field_name), field_type);
+  DECL_FIELD_CONTEXT (decl) = record_or_union_type;
+
+  if (TREE_CODE (field_type) == INTEGER_TYPE
+      && TYPE_PRECISION (field_type) != bitsize)
+    {
+      DECL_BIT_FIELD_TYPE (decl) = field_type;
+      TREE_TYPE (decl)
+	= c_build_bitfield_integer_type (bitsize, TYPE_UNSIGNED (field_type));
+    }
+
+  DECL_MODE (decl) = TYPE_MODE (TREE_TYPE (decl));
+
+  // There's no way to recover this from DWARF.
+  SET_DECL_OFFSET_ALIGN (decl, TYPE_PRECISION (pointer_sized_int_node));
+
+  tree pos = bitsize_int (bitpos);
+  pos_from_bit (&DECL_FIELD_OFFSET (decl), &DECL_FIELD_BIT_OFFSET (decl),
+		DECL_OFFSET_ALIGN (decl), pos);
+
+  DECL_SIZE (decl) = bitsize_int (bitsize);
+  DECL_SIZE_UNIT (decl) = size_int ((bitsize + BITS_PER_UNIT - 1)
+				    / BITS_PER_UNIT);
+
+  DECL_CHAIN (decl) = TYPE_FIELDS (record_or_union_type);
+  TYPE_FIELDS (record_or_union_type) = decl;
+
+  return 1;
+}
+
+int
+plugin_finish_record_or_union (cc1_plugin::connection *,
+			       gcc_type record_or_union_type_in,
+			       unsigned long size_in_bytes)
+{
+  tree record_or_union_type = convert_in (record_or_union_type_in);
+
+  gcc_assert (TREE_CODE (record_or_union_type) == RECORD_TYPE
+	      || TREE_CODE (record_or_union_type) == UNION_TYPE);
+
+  /* We built the field list in reverse order, so fix it now.  */
+  TYPE_FIELDS (record_or_union_type)
+    = nreverse (TYPE_FIELDS (record_or_union_type));
+
+  if (TREE_CODE (record_or_union_type) == UNION_TYPE)
+    {
+      /* Unions can just be handled by the generic code.  */
+      layout_type (record_or_union_type);
+    }
+  else
+    {
+      // FIXME there's no way to get this from DWARF,
+      // or even, it seems, a particularly good way to deduce it.
+      TYPE_ALIGN (record_or_union_type)
+	= TYPE_PRECISION (pointer_sized_int_node);
+
+      TYPE_SIZE (record_or_union_type) = bitsize_int (size_in_bytes
+						      * BITS_PER_UNIT);
+      TYPE_SIZE_UNIT (record_or_union_type) = size_int (size_in_bytes);
+
+      compute_record_mode (record_or_union_type);
+      finish_bitfield_layout (record_or_union_type);
+      // FIXME we have no idea about TYPE_PACKED
+    }
+
+  return 1;
+}
+
+gcc_type
+plugin_build_enum_type (cc1_plugin::connection *self,
+			gcc_type underlying_int_type_in)
+{
+  tree underlying_int_type = convert_in (underlying_int_type_in);
+
+  if (underlying_int_type == error_mark_node)
+    return convert_out (error_mark_node);
+
+  tree result = make_node (ENUMERAL_TYPE);
+
+  TYPE_PRECISION (result) = TYPE_PRECISION (underlying_int_type);
+  TYPE_UNSIGNED (result) = TYPE_UNSIGNED (underlying_int_type);
+
+  plugin_context *ctx = static_cast<plugin_context *> (self);
+  return convert_out (ctx->preserve (result));
+}
+
+int
+plugin_build_add_enum_constant (cc1_plugin::connection *,
+				gcc_type enum_type_in,
+				const char *name,
+				unsigned long value)
+{
+  tree cst, decl, cons;
+  tree enum_type = convert_in (enum_type_in);
+
+  gcc_assert (TREE_CODE (enum_type) == ENUMERAL_TYPE);
+
+  cst = build_int_cst (enum_type, value);
+  /* Note that gdb does not preserve the location of enum constants,
+     so we can't provide a decent location here.  */
+  decl = build_decl (BUILTINS_LOCATION, CONST_DECL,
+		     get_identifier (name), enum_type);
+  DECL_INITIAL (decl) = cst;
+  pushdecl_safe (decl);
+
+  cons = tree_cons (DECL_NAME (decl), cst, TYPE_VALUES (enum_type));
+  TYPE_VALUES (enum_type) = cons;
+
+  return 1;
+}
+
+int
+plugin_finish_enum_type (cc1_plugin::connection *,
+			 gcc_type enum_type_in)
+{
+  tree enum_type = convert_in (enum_type_in);
+  tree minnode, maxnode, iter;
+
+  iter = TYPE_VALUES (enum_type);
+  minnode = maxnode = TREE_VALUE (iter);
+  for (iter = TREE_CHAIN (iter);
+       iter != NULL_TREE;
+       iter = TREE_CHAIN (iter))
+    {
+      tree value = TREE_VALUE (iter);
+      if (tree_int_cst_lt (maxnode, value))
+	maxnode = value;
+      if (tree_int_cst_lt (value, minnode))
+	minnode = value;
+    }
+  TYPE_MIN_VALUE (enum_type) = minnode;
+  TYPE_MAX_VALUE (enum_type) = maxnode;
+
+  layout_type (enum_type);
+
+  return 1;
+}
+
+gcc_type
+plugin_build_function_type (cc1_plugin::connection *self,
+			    gcc_type return_type_in,
+			    const struct gcc_type_array *argument_types_in,
+			    int is_varargs)
+{
+  tree *argument_types;
+  tree return_type = convert_in (return_type_in);
+  tree result;
+
+  argument_types = new tree[argument_types_in->n_elements];
+  for (int i = 0; i < argument_types_in->n_elements; ++i)
+    argument_types[i] = convert_in (argument_types_in->elements[i]);
+
+  if (is_varargs)
+    result = build_varargs_function_type_array (return_type,
+						argument_types_in->n_elements,
+						argument_types);
+  else
+    result = build_function_type_array (return_type,
+					argument_types_in->n_elements,
+					argument_types);
+
+  delete[] argument_types;
+
+  plugin_context *ctx = static_cast<plugin_context *> (self);
+  return convert_out (ctx->preserve (result));
+}
+
+gcc_type
+plugin_int_type (cc1_plugin::connection *self,
+		 int is_unsigned, unsigned long size_in_bytes)
+{
+  tree result = c_common_type_for_size (BITS_PER_UNIT * size_in_bytes,
+					is_unsigned);
+  if (result == NULL_TREE)
+    result = error_mark_node;
+  else
+    {
+      plugin_context *ctx = static_cast<plugin_context *> (self);
+      ctx->preserve (result);
+    }
+  return convert_out (result);
+}
+
+gcc_type
+plugin_float_type (cc1_plugin::connection *,
+		   unsigned long size_in_bytes)
+{
+  if (BITS_PER_UNIT * size_in_bytes == TYPE_PRECISION (float_type_node))
+    return convert_out (float_type_node);
+  if (BITS_PER_UNIT * size_in_bytes == TYPE_PRECISION (double_type_node))
+    return convert_out (double_type_node);
+  if (BITS_PER_UNIT * size_in_bytes == TYPE_PRECISION (long_double_type_node))
+    return convert_out (long_double_type_node);
+  return convert_out (error_mark_node);
+}
+
+gcc_type
+plugin_void_type (cc1_plugin::connection *)
+{
+  return convert_out (void_type_node);
+}
+
+gcc_type
+plugin_bool_type (cc1_plugin::connection *)
+{
+  return convert_out (boolean_type_node);
+}
+
+gcc_type
+plugin_build_array_type (cc1_plugin::connection *self,
+			 gcc_type element_type_in, int num_elements)
+{
+  tree element_type = convert_in (element_type_in);
+  tree result;
+
+  if (num_elements == -1)
+    result = build_array_type (element_type, NULL_TREE);
+  else
+    result = build_array_type_nelts (element_type, num_elements);
+
+  plugin_context *ctx = static_cast<plugin_context *> (self);
+  return convert_out (ctx->preserve (result));
+}
+
+gcc_type
+plugin_build_vla_array_type (cc1_plugin::connection *self,
+			     gcc_type element_type_in,
+			     const char *upper_bound_name)
+{
+  tree element_type = convert_in (element_type_in);
+  tree upper_bound = lookup_name (get_identifier (upper_bound_name));
+  tree range = build_index_type (upper_bound);
+
+  tree result = build_array_type (element_type, range);
+  C_TYPE_VARIABLE_SIZE (result) = 1;
+
+  plugin_context *ctx = static_cast<plugin_context *> (self);
+  return convert_out (ctx->preserve (result));
+}
+
+gcc_type
+plugin_build_qualified_type (cc1_plugin::connection *,
+			     gcc_type unqualified_type_in,
+			     enum gcc_qualifiers qualifiers)
+{
+  tree unqualified_type = convert_in (unqualified_type_in);
+  int quals = 0;
+
+  if ((qualifiers & GCC_QUALIFIER_CONST) != 0)
+    quals |= TYPE_QUAL_CONST;
+  if ((qualifiers & GCC_QUALIFIER_VOLATILE) != 0)
+    quals |= TYPE_QUAL_VOLATILE;
+  if ((qualifiers & GCC_QUALIFIER_RESTRICT) != 0)
+    quals |= TYPE_QUAL_RESTRICT;
+
+  return convert_out (build_qualified_type (unqualified_type, quals));
+}
+
+gcc_type
+plugin_build_complex_type (cc1_plugin::connection *self,
+			   gcc_type base_type)
+{
+  plugin_context *ctx = static_cast<plugin_context *> (self);
+  return convert_out (ctx->preserve (build_complex_type (convert_in (base_type))));
+}
+
+gcc_type
+plugin_build_vector_type (cc1_plugin::connection *self,
+			  gcc_type base_type, int nunits)
+{
+  plugin_context *ctx = static_cast<plugin_context *> (self);
+  return convert_out (ctx->preserve (build_vector_type (convert_in (base_type),
+							nunits)));
+}
+
+int
+plugin_build_constant (cc1_plugin::connection *self, gcc_type type_in,
+		       const char *name, unsigned long value,
+		       const char *filename, unsigned int line_number)
+{
+  plugin_context *ctx = static_cast<plugin_context *> (self);
+  tree cst, decl;
+  tree type = convert_in (type_in);
+
+  cst = build_int_cst (type, value);
+  decl = build_decl (ctx->get_source_location (filename, line_number),
+		     CONST_DECL, get_identifier (name), type);
+  DECL_INITIAL (decl) = cst;
+  pushdecl_safe (decl);
+
+  return 1;
+}
+
+gcc_type
+plugin_error (cc1_plugin::connection *,
+	      const char *message)
+{
+  error ("%s", message);
+  return convert_out (error_mark_node);
+}
+
+
+
+// Perform GC marking.
+
+static void
+gc_mark (void *, void *)
+{
+  if (current_context != NULL)
+    current_context->mark ();
+}
+
+#ifdef __GNUC__
+#pragma GCC visibility push(default)
+#endif
+
+int
+plugin_init (struct plugin_name_args *plugin_info,
+	     struct plugin_gcc_version *)
+{
+  long fd = -1;
+  for (int i = 0; i < plugin_info->argc; ++i)
+    {
+      if (strcmp (plugin_info->argv[i].key, "fd") == 0)
+	{
+	  char *tail;
+	  errno = 0;
+	  fd = strtol (plugin_info->argv[i].value, &tail, 0);
+	  if (*tail != '\0' || errno != 0)
+	    fatal_error ("%s: invalid file descriptor argument to plugin",
+			 plugin_info->base_name);
+	  break;
+	}
+    }
+  if (fd == -1)
+    fatal_error ("%s: required plugin argument %<fd%> is missing",
+		 plugin_info->base_name);
+
+  current_context = new plugin_context (fd);
+
+  // Handshake.
+  cc1_plugin::protocol_int version;
+  if (!current_context->require ('H')
+      || ! ::cc1_plugin::unmarshall (current_context, &version))
+    fatal_error ("%s: handshake failed", plugin_info->base_name);
+  if (version != GCC_C_FE_VERSION_0)
+    fatal_error ("%s: unknown version in handshake", plugin_info->base_name);
+
+  register_callback (plugin_info->base_name, PLUGIN_PRAGMAS,
+		     plugin_init_extra_pragmas, NULL);
+  register_callback (plugin_info->base_name, PLUGIN_PRE_GENERICIZE,
+		     rewrite_decls_to_addresses, NULL);
+  register_callback (plugin_info->base_name, PLUGIN_GGC_MARKING,
+		     gc_mark, NULL);
+
+  lang_hooks.print_error_function = plugin_print_error_function;
+
+#define GCC_METHOD0(R, N)			\
+  {						\
+    cc1_plugin::callback_ftype *fun		\
+      = cc1_plugin::callback<R, plugin_ ## N>;	\
+    current_context->add_callback (# N, fun);	\
+  }
+#define GCC_METHOD1(R, N, A)				\
+  {							\
+    cc1_plugin::callback_ftype *fun			\
+      = cc1_plugin::callback<R, A, plugin_ ## N>;	\
+    current_context->add_callback (# N, fun);		\
+  }
+#define GCC_METHOD2(R, N, A, B)				\
+  {							\
+    cc1_plugin::callback_ftype *fun			\
+      = cc1_plugin::callback<R, A, B, plugin_ ## N>;	\
+    current_context->add_callback (# N, fun);		\
+  }
+#define GCC_METHOD3(R, N, A, B, C)			\
+  {							\
+    cc1_plugin::callback_ftype *fun			\
+      = cc1_plugin::callback<R, A, B, C, plugin_ ## N>;	\
+    current_context->add_callback (# N, fun);		\
+  }
+#define GCC_METHOD4(R, N, A, B, C, D)		\
+  {						\
+    cc1_plugin::callback_ftype *fun		\
+      = cc1_plugin::callback<R, A, B, C, D,	\
+			     plugin_ ## N>;	\
+    current_context->add_callback (# N, fun);	\
+  }
+#define GCC_METHOD5(R, N, A, B, C, D, E)	\
+  {						\
+    cc1_plugin::callback_ftype *fun		\
+      = cc1_plugin::callback<R, A, B, C, D, E,	\
+			     plugin_ ## N>;	\
+    current_context->add_callback (# N, fun);	\
+  }
+#define GCC_METHOD7(R, N, A, B, C, D, E, F, G)		\
+  {							\
+    cc1_plugin::callback_ftype *fun			\
+      = cc1_plugin::callback<R, A, B, C, D, E, F, G,	\
+			     plugin_ ## N>;		\
+    current_context->add_callback (# N, fun);		\
+  }
+
+#include "gcc-c-fe.def"
+
+#undef GCC_METHOD0
+#undef GCC_METHOD1
+#undef GCC_METHOD2
+#undef GCC_METHOD3
+#undef GCC_METHOD4
+#undef GCC_METHOD5
+#undef GCC_METHOD7
+
+  return 0;
+}