Add Go frontend, libgo library, and Go testsuite.

gcc/:
	* gcc.c (default_compilers): Add entry for ".go".
	* common.opt: Add -static-libgo as a driver option.
	* doc/install.texi (Configuration): Mention libgo as an option for
	--enable-shared.  Mention go as an option for --enable-languages.
	* doc/invoke.texi (Overall Options): Mention .go as a file name
	suffix.  Mention go as a -x option.
	* doc/frontends.texi (G++ and GCC): Mention Go as a supported
	language.
	* doc/sourcebuild.texi (Top Level): Mention libgo.
	* doc/standards.texi (Standards): Add section on Go language.
	Move references for other languages into their own section.
	* doc/contrib.texi (Contributors): Mention that I contributed the
	Go frontend.
gcc/testsuite/:
	* lib/go.exp: New file.
	* lib/go-dg.exp: New file.
	* lib/go-torture.exp: New file.
	* lib/target-supports.exp (check_compile): Match // Go.

From-SVN: r167407

1 files changed, 404 insertions, 0 deletions

diff --git a/gcc/go/go-lang.c b/gcc/go/go-lang.c
new file mode 100644
index 0000000..9c85ab7
--- /dev/null
+++ b/gcc/go/go-lang.c
@@ -0,0 +1,404 @@
+/* go-lang.c -- Go frontend gcc interface.
+   Copyright (C) 2009, 2010 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 "config.h"
+#include "system.h"
+#include "ansidecl.h"
+#include "coretypes.h"
+#include "opts.h"
+#include "tree.h"
+#include "gimple.h"
+#include "ggc.h"
+#include "toplev.h"
+#include "debug.h"
+#include "options.h"
+#include "flags.h"
+#include "convert.h"
+#include "diagnostic.h"
+#include "langhooks.h"
+#include "langhooks-def.h"
+#include "except.h"
+#include "target.h"
+
+#include <mpfr.h>
+
+#include "go-c.h"
+
+/* Language-dependent contents of a type.  */
+
+struct GTY(()) lang_type
+{
+  char dummy;
+};
+
+/* Language-dependent contents of a decl.  */
+
+struct GTY(()) lang_decl
+{
+  char dummy;
+};
+
+/* Language-dependent contents of an identifier.  This must include a
+   tree_identifier.  */
+
+struct GTY(()) lang_identifier
+{
+  struct tree_identifier common;
+};
+
+/* The resulting tree type.  */
+
+union GTY((desc ("TREE_CODE (&%h.generic) == IDENTIFIER_NODE"),
+	   chain_next ("(union lang_tree_node *) TREE_CHAIN (&%h.generic)")))
+lang_tree_node
+{
+  union tree_node GTY((tag ("0"),
+		       desc ("tree_node_structure (&%h)"))) generic;
+  struct lang_identifier GTY((tag ("1"))) identifier;
+};
+
+/* We don't use language_function.  */
+
+struct GTY(()) language_function
+{
+  int dummy;
+};
+
+/* Language hooks.  */
+
+static bool
+go_langhook_init (void)
+{
+  build_common_tree_nodes (false);
+
+  /* The sizetype may be "unsigned long" or "unsigned long long".  */
+  if (TYPE_MODE (long_unsigned_type_node) == ptr_mode)
+    size_type_node = long_unsigned_type_node;
+  else if (TYPE_MODE (long_long_unsigned_type_node) == ptr_mode)
+    size_type_node = long_long_unsigned_type_node;
+  else
+    size_type_node = long_unsigned_type_node;
+  set_sizetype (size_type_node);
+
+  build_common_tree_nodes_2 (0);
+
+  /* We must create the gogo IR after calling build_common_tree_nodes
+     (because Gogo::define_builtin_function_trees refers indirectly
+     to, e.g., unsigned_char_type_node) but before calling
+     build_common_builtin_nodes (because it calls, indirectly,
+     go_type_for_size).  */
+  go_create_gogo (INT_TYPE_SIZE, FLOAT_TYPE_SIZE, POINTER_SIZE);
+
+  build_common_builtin_nodes ();
+
+  /* I don't know why this is not done by any of the above.  */
+  void_list_node = build_tree_list (NULL_TREE, void_type_node);
+
+  /* The default precision for floating point numbers.  This is used
+     for floating point constants with abstract type.  This may
+     eventually be controllable by a command line option.  */
+  mpfr_set_default_prec (128);
+
+  /* Go uses exceptions.  */
+  using_eh_for_cleanups ();
+
+  return true;
+}
+
+/* The option mask.  */
+
+static unsigned int
+go_langhook_option_lang_mask (void)
+{
+  return CL_Go;
+}
+
+/* Initialize the options structure.  */
+
+static void
+go_langhook_init_options_struct (struct gcc_options *opts)
+{
+  /* Go says that signed overflow is precisely defined.  */
+  opts->x_flag_wrapv = 1;
+
+  /* We default to using strict aliasing, since Go pointers are safe.
+     This is turned off for code that imports the "unsafe" package,
+     because using unsafe.pointer violates C style aliasing
+     requirements.  */
+  opts->x_flag_strict_aliasing = 1;
+
+  /* Default to avoiding range issues for complex multiply and
+     divide.  */
+  opts->x_flag_complex_method = 2;
+
+  /* The builtin math functions should not set errno.  */
+  opts->x_flag_errno_math = 0;
+
+  /* By default assume that floating point math does not trap.  */
+  opts->x_flag_trapping_math = 0;
+
+  /* We turn on stack splitting if we can.  */
+  if (targetm.supports_split_stack (false, opts))
+    opts->x_flag_split_stack = 1;
+
+  /* Exceptions are used to handle recovering from panics.  */
+  opts->x_flag_exceptions = 1;
+  opts->x_flag_non_call_exceptions = 1;
+}
+
+/* Handle Go specific options.  Return 0 if we didn't do anything.  */
+
+static bool
+go_langhook_handle_option (
+    size_t scode,
+    const char *arg,
+    int value ATTRIBUTE_UNUSED,
+    int kind ATTRIBUTE_UNUSED,
+    location_t loc ATTRIBUTE_UNUSED,
+    const struct cl_option_handlers *handlers ATTRIBUTE_UNUSED)
+{
+  enum opt_code code = (enum opt_code) scode;
+  bool ret = true;
+
+  switch (code)
+    {
+    case OPT_I:
+    case OPT_L:
+      /* For the compiler, we currently handle -I and -L exactly the
+	 same way: they give us a directory to search for import
+	 statements.  */
+      go_add_search_path (arg);
+      break;
+
+    case OPT_fgo_dump_:
+      ret = go_enable_dump (arg) ? true : false;
+      break;
+
+    case OPT_fgo_prefix_:
+      go_set_prefix (arg);
+      break;
+
+    default:
+      /* Just return 1 to indicate that the option is valid.  */
+      break;
+    }
+
+  return ret;
+}
+
+/* Run after parsing options.  */
+
+static bool
+go_langhook_post_options (const char **pfilename ATTRIBUTE_UNUSED)
+{
+  gcc_assert (num_in_fnames > 0);
+
+  if (flag_excess_precision_cmdline == EXCESS_PRECISION_DEFAULT)
+    flag_excess_precision_cmdline = EXCESS_PRECISION_STANDARD;
+
+  /* Returning false means that the backend should be used.  */
+  return false;
+}
+
+static void
+go_langhook_parse_file (void)
+{
+  go_parse_input_files (in_fnames, num_in_fnames, flag_syntax_only,
+			go_require_return_statement);
+}
+
+static tree
+go_langhook_type_for_size (unsigned int bits, int unsignedp)
+{
+  return go_type_for_size (bits, unsignedp);
+}
+
+static tree
+go_langhook_type_for_mode (enum machine_mode mode, int unsignedp)
+{
+  return go_type_for_mode (mode, unsignedp);
+}
+
+/* Record a builtin function.  We just ignore builtin functions.  */
+
+static tree
+go_langhook_builtin_function (tree decl)
+{
+  return decl;
+}
+
+static int
+go_langhook_global_bindings_p (void)
+{
+  return current_function_decl == NULL ? 1 : 0;
+}
+
+/* Push a declaration into the current binding level.  We can't
+   usefully implement this since we don't want to convert from tree
+   back to one of our internal data structures.  I think the only way
+   this is used is to record a decl which is to be returned by
+   getdecls, and we could implement it for that purpose if
+   necessary.  */
+
+static tree
+go_langhook_pushdecl (tree decl ATTRIBUTE_UNUSED)
+{
+  gcc_unreachable ();
+}
+
+/* This hook is used to get the current list of declarations as trees.
+   We don't support that; instead we use the write_globals hook.  This
+   can't simply crash because it is called by -gstabs.  */
+
+static tree
+go_langhook_getdecls (void)
+{
+  return NULL;
+}
+
+/* Write out globals.  */
+
+static void
+go_langhook_write_globals (void)
+{
+  go_write_globals ();
+}
+
+/* Go specific gimplification.  We need to gimplify
+   CALL_EXPR_STATIC_CHAIN, because the gimplifier doesn't handle
+   it.  */
+
+static int
+go_langhook_gimplify_expr (tree *expr_p, gimple_seq *pre_p, gimple_seq *post_p)
+{
+  if (TREE_CODE (*expr_p) == CALL_EXPR
+      && CALL_EXPR_STATIC_CHAIN (*expr_p) != NULL_TREE)
+    gimplify_expr (&CALL_EXPR_STATIC_CHAIN (*expr_p), pre_p, post_p,
+		   is_gimple_val, fb_rvalue);
+  return GS_UNHANDLED;
+}
+
+/* Return a decl for the exception personality function.  The function
+   itself is implemented in libgo/runtime/go-unwind.c.  */
+
+static tree
+go_langhook_eh_personality (void)
+{
+  static tree personality_decl;
+  if (personality_decl == NULL_TREE)
+    {
+      personality_decl = build_personality_function ("gccgo");
+      go_preserve_from_gc (personality_decl);
+    }
+  return personality_decl;
+}
+
+/* Functions called directly by the generic backend.  */
+
+tree
+convert (tree type, tree expr)
+{
+  if (type == error_mark_node
+      || expr == error_mark_node
+      || TREE_TYPE (expr) == error_mark_node)
+    return error_mark_node;
+
+  if (type == TREE_TYPE (expr))
+    return expr;
+
+  if (TYPE_MAIN_VARIANT (type) == TYPE_MAIN_VARIANT (TREE_TYPE (expr)))
+    return fold_convert (type, expr);
+
+  switch (TREE_CODE (type))
+    {
+    case VOID_TYPE:
+    case BOOLEAN_TYPE:
+      return fold_convert (type, expr);
+    case INTEGER_TYPE:
+      return fold (convert_to_integer (type, expr));
+    case POINTER_TYPE:
+      return fold (convert_to_pointer (type, expr));
+    case REAL_TYPE:
+      return fold (convert_to_real (type, expr));
+    case COMPLEX_TYPE:
+      return fold (convert_to_complex (type, expr));
+    default:
+      break;
+    }
+
+  gcc_unreachable ();
+}
+
+/* FIXME: This is a hack to preserve trees that we create from the
+   garbage collector.  */
+
+static GTY(()) tree go_gc_root;
+
+void
+go_preserve_from_gc (tree t)
+{
+  go_gc_root = tree_cons (NULL_TREE, t, go_gc_root);
+}
+
+/* Convert an identifier for use in an error message.  */
+
+const char *
+go_localize_identifier (const char *ident)
+{
+  return identifier_to_locale (ident);
+}
+
+#undef LANG_HOOKS_NAME
+#undef LANG_HOOKS_INIT
+#undef LANG_HOOKS_OPTION_LANG_MASK
+#undef LANG_HOOKS_INIT_OPTIONS_STRUCT
+#undef LANG_HOOKS_HANDLE_OPTION
+#undef LANG_HOOKS_POST_OPTIONS
+#undef LANG_HOOKS_PARSE_FILE
+#undef LANG_HOOKS_TYPE_FOR_MODE
+#undef LANG_HOOKS_TYPE_FOR_SIZE
+#undef LANG_HOOKS_BUILTIN_FUNCTION
+#undef LANG_HOOKS_GLOBAL_BINDINGS_P
+#undef LANG_HOOKS_PUSHDECL
+#undef LANG_HOOKS_GETDECLS
+#undef LANG_HOOKS_WRITE_GLOBALS
+#undef LANG_HOOKS_GIMPLIFY_EXPR
+#undef LANG_HOOKS_EH_PERSONALITY
+
+#define LANG_HOOKS_NAME			"GNU Go"
+#define LANG_HOOKS_INIT			go_langhook_init
+#define LANG_HOOKS_OPTION_LANG_MASK	go_langhook_option_lang_mask
+#define LANG_HOOKS_INIT_OPTIONS_STRUCT	go_langhook_init_options_struct
+#define LANG_HOOKS_HANDLE_OPTION	go_langhook_handle_option
+#define LANG_HOOKS_POST_OPTIONS		go_langhook_post_options
+#define LANG_HOOKS_PARSE_FILE		go_langhook_parse_file
+#define LANG_HOOKS_TYPE_FOR_MODE	go_langhook_type_for_mode
+#define LANG_HOOKS_TYPE_FOR_SIZE	go_langhook_type_for_size
+#define LANG_HOOKS_BUILTIN_FUNCTION	go_langhook_builtin_function
+#define LANG_HOOKS_GLOBAL_BINDINGS_P	go_langhook_global_bindings_p
+#define LANG_HOOKS_PUSHDECL		go_langhook_pushdecl
+#define LANG_HOOKS_GETDECLS		go_langhook_getdecls
+#define LANG_HOOKS_WRITE_GLOBALS	go_langhook_write_globals
+#define LANG_HOOKS_GIMPLIFY_EXPR	go_langhook_gimplify_expr
+#define LANG_HOOKS_EH_PERSONALITY	go_langhook_eh_personality
+
+struct lang_hooks lang_hooks = LANG_HOOKS_INITIALIZER;
+
+#include "gt-go-go-lang.h"
+#include "gtype-go.h"