700-debian_cp-pass-by-reference.patch

這是一個實時嵌入式作業系統 實作了MCS51 ARM等MCU

    Contributed by Jim Blandy <[e-mail]>
 
-   Copyright 2001, 2002, 2003 Free Software Foundation, Inc.
+   Copyright 2001, 2002, 2003, 2004 Free Software Foundation, Inc.
 
    This file is part of GDB.
 
@@ -419,6 +419,84 @@ gnuv3_baseclass_offset (struct type *typ
   return base_offset;
 }
 
+/* Return nonzero if a type should be passed by reference.
+
+   The rule in the v3 ABI document comes from section 3.1.1.  If the
+   type has a non-trivial copy constructor or destructor, then the
+   caller must make a copy (by calling the copy constructor if there
+   is one or perform the copy itself otherwise), pass the address of
+   the copy, and then destroy the temporary (if necessary).
+
+   For return values with non-trivial copy constructors or
+   destructors, space will be allocated in the caller, and a pointer
+   will be passed as the first argument (preceding "this").
+
+   We don't have a bulletproof mechanism for determining whether a
+   constructor or destructor is trivial.  For GCC and DWARF2 debug
+   information, we can check the artificial flag.
+
+   We don't do anything with the constructors or destructors yet,
+   but we have to get the argument passing right anyway.  */
+static int
+gnuv3_pass_by_reference (struct type *type)
+{
+  int fieldnum, fieldelem, basenum;
+
+  CHECK_TYPEDEF (type);
+
+  /* We're only interested in things that can have methods.  */
+  if (TYPE_CODE (type) != TYPE_CODE_STRUCT
+      && TYPE_CODE (type) != TYPE_CODE_CLASS
+      && TYPE_CODE (type) != TYPE_CODE_UNION)
+    return 0;
+
+  for (fieldnum = 0; fieldnum < TYPE_NFN_FIELDS (type); fieldnum++)
+    for (fieldelem = 0; fieldelem < TYPE_FN_FIELDLIST_LENGTH (type, fieldnum);
+	 fieldelem++)
+      {
+	struct fn_field *fn = TYPE_FN_FIELDLIST1 (type, fieldnum);
+	char *name = TYPE_FN_FIELDLIST_NAME (type, fieldnum);
+	struct type *fieldtype = TYPE_FN_FIELD_TYPE (fn, fieldelem);
+
+	/* If this function is marked as artificial, it is compiler-generated,
+	   and we assume it is trivial.  */
+	if (TYPE_FN_FIELD_ARTIFICIAL (fn, fieldelem))
+	  continue;
+
+	/* If we've found a destructor, we must pass this by reference.  */
+	if (name[0] == '~')
+	  return 1;
+
+	/* If the mangled name of this method doesn't indicate that it
+	   is a constructor, we're not interested.
+
+	   FIXME drow/2004-05-27: We could do this using the name of
+	   the method and the name of the class instead of dealing
+	   with the mangled name.  We don't have a convenient function
+	   to strip off both leading scope qualifiers and trailing
+	   template arguments yet.  */
+	if (!is_constructor_name (TYPE_FN_FIELD_PHYSNAME (fn, fieldelem)))
+	  continue;
+
+	/* If this method takes two arguments, and the second argument is
+	   a reference to this class, then it is a copy constructor.  */
+	if (TYPE_NFIELDS (fieldtype) == 2
+	    && TYPE_CODE (TYPE_FIELD_TYPE (fieldtype, 1)) == TYPE_CODE_REF
+	    && check_typedef (TYPE_TARGET_TYPE (TYPE_FIELD_TYPE (fieldtype, 1))) == type)
+	  return 1;
+      }
+
+  /* Even if all the constructors and destructors were artificial, one
+     of them may have invoked a non-artificial constructor or
+     destructor in a base class.  If any base class needs to be passed
+     by reference, so does this class.  */
+  for (basenum = 0; basenum < TYPE_N_BASECLASSES (type); basenum++)
+    if (gnuv3_pass_by_reference (TYPE_BASECLASS (type, basenum)))
+      return 1;
+
+  return 0;
+}
+
 static void
 init_gnuv3_ops (void)
 {
@@ -434,6 +512,7 @@ init_gnuv3_ops (void)
   gnu_v3_abi_ops.rtti_type = gnuv3_rtti_type;
   gnu_v3_abi_ops.virtual_fn_field = gnuv3_virtual_fn_field;
   gnu_v3_abi_ops.baseclass_offset = gnuv3_baseclass_offset;
+  gnu_v3_abi_ops.pass_by_reference = gnuv3_pass_by_reference;
 }
 
 extern initialize_file_ftype _initialize_gnu_v3_abi; /* -Wmissing-prototypes */
Index: gdb-6.3/gdb/hpacc-abi.c
===================================================================
--- gdb-6.3.orig/gdb/hpacc-abi.c	2003-06-08 14:27:13.000000000 -0400
+++ gdb-6.3/gdb/hpacc-abi.c	2004-11-10 12:30:07.000000000 -0500
@@ -3,7 +3,7 @@
    Most of the real code is from HP, i've just fiddled it to fit in
    the C++ ABI abstraction framework.
 
-   Copyright 2001 Free Software Foundation, Inc.
+   Copyright 2001, 2002, 2003 Free Software Foundation, Inc.
 
    This file is part of GDB.
 
Index: gdb-6.3/gdb/Makefile.in
===================================================================
--- gdb-6.3.orig/gdb/Makefile.in	2004-11-10 12:30:06.000000000 -0500
+++ gdb-6.3/gdb/Makefile.in	2004-11-10 12:30:07.000000000 -0500
@@ -2073,7 +2073,7 @@ ia64-tdep.o: ia64-tdep.c $(defs_h) $(inf
 infcall.o: infcall.c $(defs_h) $(breakpoint_h) $(target_h) $(regcache_h) \
 	$(inferior_h) $(gdb_assert_h) $(block_h) $(gdbcore_h) $(language_h) \
 	$(objfiles_h) $(gdbcmd_h) $(command_h) $(gdb_string_h) $(infcall_h) \
-	$(dummy_frame_h)
+	$(dummy_frame_h) $(cp_abi_h)
 inf-child.o: inf-child.c $(defs_h) $(regcache_h) $(memattr_h) $(symtab_h) \
 	$(target_h) $(inferior_h) $(gdb_string_h)
 infcmd.o: infcmd.c $(defs_h) $(gdb_string_h) $(symtab_h) $(gdbtypes_h) \
Index: gdb-6.3/gdb/testsuite/gdb.cp/pass-by-ref.exp
===================================================================
--- /dev/null	1970-01-01 00:00:00.000000000 +0000
+++ gdb-6.3/gdb/testsuite/gdb.cp/pass-by-ref.exp	2004-11-11 09:48:00.498518899 -0500
@@ -0,0 +1,38 @@
+# This testcase is part of GDB, the GNU debugger.
+
+# Copyright 2004 Free Software Foundation, Inc.
+
+# This program 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 of the License, or
+# (at your option) any later version.
+#
+# This program 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 this program; if not, write to the Free Software
+# Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  
+
+# Check that GDB can call C++ functions whose parameters have
+# object type, but are passed by reference.
+
+set testfile "pass-by-ref"
+set srcfile ${testfile}.cc
+set binfile ${objdir}/${subdir}/${testfile}
+if { [gdb_compile "${srcdir}/${subdir}/${srcfile}" "${binfile}" executable {debug}] != "" } {
+    return -1
+}
+
+gdb_exit
+gdb_start
+gdb_reinitialize_dir $srcdir/$subdir
+gdb_load ${binfile}
+
+if ![runto_main] then {
+    return -1
+}
+
+gdb_test "print foo (global_obj)" " = 3" "call function"
Index: gdb-6.3/gdb/testsuite/gdb.cp/pass-by-ref.cc
===================================================================
--- /dev/null	1970-01-01 00:00:00.000000000 +0000
+++ gdb-6.3/gdb/testsuite/gdb.cp/pass-by-ref.cc	2004-11-11 09:44:17.815014667 -0500
@@ -0,0 +1,57 @@
+/* This testcase is part of GDB, the GNU debugger.
+
+   Copyright 2004 Free Software Foundation, Inc.
+
+   This program 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 of the License, or
+   (at your option) any later version.
+
+   This program 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 this program; if not, write to the Free Software
+   Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307,
+   USA.  */
+
+class Obj {
+public:
+  Obj ();
+  Obj (const Obj &);
+  ~Obj ();
+  int var[2];
+};
+
+int foo (Obj arg)
+{
+  return arg.var[0] + arg.var[1];
+}
+
+Obj::Obj ()
+{
+  var[0] = 1;
+  var[1] = 2;
+}
+
+Obj::Obj (const Obj &obj)
+{
+  var[0] = obj.var[0];
+  var[1] = obj.var[1];
+}
+
+Obj::~Obj ()
+{
+
+}
+
+Obj global_obj;
+
+int
+main ()
+{
+  int bar = foo (global_obj);
+  return bar;
+}