pass and return by reference.
* cp-abi.c (cp_pass_by_reference): New.
* cp-abi.h (cp_pass_by_reference): Declare.
(struct cp_abi_ops): Add pass_by_reference.
* gnu-v3-abi.c (gnuv3_pass_by_reference): New.
(init_gnuv3_ops): Set pass_by_reference.
* language.c (language_pass_by_reference): New.
(default_pass_by_reference): New.
(unknown_language_defn, auto_language_defn, local_language_defn): Add
default_pass_by_reference.
* langauge.h (struct language_defn): Add la_pass_by_reference.
(language_pass_by_reference, default_pass_by_reference): Declare.
* ada-lang.c (ada_language_defn): Add default_pass_by_reference.
* c-lang.c (c_language_defn, asm_language_defn)
(minimal_language_defn): Likewise.
(cplus_language_defn): Add cp_pass_by_reference.
* f-lang.c (f_language_defn): Add default_pass_by_reference.
* jv-lang.c (java_language_defn): Likewise.
* m2-lang.c (m2_language_defn): Likewise.
* objc-lang.c (objc_language_defn): Likewise.
* p-lang.c (pascal_language_defn): Likewise.
* scm-lang.c (scm_language_defn): Likewise
* gdb.cp/pass-by-ref.cc, gdb.cp/pass-by-ref.exp: New files.
+2007-09-23 Daniel Jacobowitz <dan@codesourcery.com>
+
+ * infcall.c (call_function_by_hand): Handle language-specific
+ pass and return by reference.
+
+ * cp-abi.c (cp_pass_by_reference): New.
+ * cp-abi.h (cp_pass_by_reference): Declare.
+ (struct cp_abi_ops): Add pass_by_reference.
+ * gnu-v3-abi.c (gnuv3_pass_by_reference): New.
+ (init_gnuv3_ops): Set pass_by_reference.
+
+ * language.c (language_pass_by_reference): New.
+ (default_pass_by_reference): New.
+ (unknown_language_defn, auto_language_defn, local_language_defn): Add
+ default_pass_by_reference.
+ * langauge.h (struct language_defn): Add la_pass_by_reference.
+ (language_pass_by_reference, default_pass_by_reference): Declare.
+ * ada-lang.c (ada_language_defn): Add default_pass_by_reference.
+ * c-lang.c (c_language_defn, asm_language_defn)
+ (minimal_language_defn): Likewise.
+ (cplus_language_defn): Add cp_pass_by_reference.
+ * f-lang.c (f_language_defn): Add default_pass_by_reference.
+ * jv-lang.c (java_language_defn): Likewise.
+ * m2-lang.c (m2_language_defn): Likewise.
+ * objc-lang.c (objc_language_defn): Likewise.
+ * p-lang.c (pascal_language_defn): Likewise.
+ * scm-lang.c (scm_language_defn): Likewise
+
2007-09-23 Vladimir Prus <vladimir@codesourcery.com>
Allow a code breakpoint to have several locations
ada_get_gdb_completer_word_break_characters,
ada_language_arch_info,
ada_print_array_index,
+ default_pass_by_reference,
LANG_MAGIC
};
default_word_break_characters,
c_language_arch_info,
default_print_array_index,
+ default_pass_by_reference,
LANG_MAGIC
};
default_word_break_characters,
cplus_language_arch_info,
default_print_array_index,
+ cp_pass_by_reference,
LANG_MAGIC
};
default_word_break_characters,
c_language_arch_info, /* FIXME: la_language_arch_info. */
default_print_array_index,
+ default_pass_by_reference,
LANG_MAGIC
};
default_word_break_characters,
c_language_arch_info,
default_print_array_index,
+ default_pass_by_reference,
LANG_MAGIC
};
return (*current_cp_abi.method_ptr_to_value) (this_p, method_ptr);
}
+int
+cp_pass_by_reference (struct type *type)
+{
+ if ((current_cp_abi.pass_by_reference) == NULL)
+ return 0;
+ return (*current_cp_abi.pass_by_reference) (type);
+}
+
/* Set the current C++ ABI to SHORT_NAME. */
static int
CORE_ADDR cplus_skip_trampoline (struct frame_info *frame, CORE_ADDR stop_pc);
+/* Return non-zero if an argument of type TYPE should be passed by reference
+ instead of value. */
+extern int cp_pass_by_reference (struct type *type);
+
struct cp_abi_ops
{
const char *shortname;
void (*make_method_ptr) (gdb_byte *, CORE_ADDR, int);
struct value * (*method_ptr_to_value) (struct value **, struct value *);
CORE_ADDR (*skip_trampoline) (struct frame_info *, CORE_ADDR);
+ int (*pass_by_reference) (struct type *type);
};
default_word_break_characters,
f_language_arch_info,
default_print_array_index,
+ default_pass_by_reference,
LANG_MAGIC
};
return real_stop_pc;
}
+/* 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,
+ but we have to get the argument passing right anyway. */
+static int
+gnuv3_pass_by_reference (struct type *type)
+{
+ int fieldnum, fieldelem;
+
+ 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/2007-09-23: 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. Similarly for members, which
+ are constructed whenever this class is. We do not need to worry
+ about recursive loops here, since we are only looking at members
+ of complete class type. */
+ for (fieldnum = 0; fieldnum < TYPE_NFIELDS (type); fieldnum++)
+ if (gnuv3_pass_by_reference (TYPE_FIELD_TYPE (type, fieldnum)))
+ return 1;
+
+ return 0;
+}
+
static void
init_gnuv3_ops (void)
{
gnu_v3_abi_ops.make_method_ptr = gnuv3_make_method_ptr;
gnu_v3_abi_ops.method_ptr_to_value = gnuv3_method_ptr_to_value;
gnu_v3_abi_ops.skip_trampoline = gnuv3_skip_trampoline;
+ gnu_v3_abi_ops.pass_by_reference = gnuv3_pass_by_reference;
}
extern initialize_file_ftype _initialize_gnu_v3_abi; /* -Wmissing-prototypes */
{
CORE_ADDR sp;
CORE_ADDR dummy_addr;
- struct type *values_type;
- unsigned char struct_return;
+ struct type *values_type, *target_values_type;
+ unsigned char struct_return = 0, lang_struct_return = 0;
CORE_ADDR struct_addr = 0;
struct regcache *retbuf;
struct cleanup *retbuf_cleanup;
struct regcache *caller_regcache;
struct cleanup *caller_regcache_cleanup;
struct frame_id dummy_id;
+ struct cleanup *args_cleanup;
if (TYPE_CODE (ftype) == TYPE_CODE_PTR)
ftype = check_typedef (TYPE_TARGET_TYPE (ftype));
using_gcc = (b == NULL ? 2 : BLOCK_GCC_COMPILED (b));
}
- /* Are we returning a value using a structure return or a normal
- value return? */
+ /* Are we returning a value using a structure return (passing a
+ hidden argument pointing to storage) or a normal value return?
+ There are two cases: language-mandated structure return and
+ target ABI structure return. The variable STRUCT_RETURN only
+ describes the latter. The language version is handled by passing
+ the return location as the first parameter to the function,
+ even preceding "this". This is different from the target
+ ABI version, which is target-specific; for instance, on ia64
+ the first argument is passed in out0 but the hidden structure
+ return pointer would normally be passed in r8. */
+
+ if (language_pass_by_reference (values_type))
+ {
+ lang_struct_return = 1;
- struct_return = using_struct_return (values_type, using_gcc);
+ /* Tell the target specific argument pushing routine not to
+ expect a value. */
+ target_values_type = builtin_type_void;
+ }
+ else
+ {
+ struct_return = using_struct_return (values_type, using_gcc);
+ target_values_type = values_type;
+ }
/* Determine the location of the breakpoint (and possibly other
stuff) that the called function will return to. The SPARC, for a
if (gdbarch_inner_than (current_gdbarch, 1, 2))
{
sp = push_dummy_code (current_gdbarch, sp, funaddr,
- using_gcc, args, nargs, values_type,
+ using_gcc, args, nargs, target_values_type,
&real_pc, &bp_addr, get_current_regcache ());
dummy_addr = sp;
}
{
dummy_addr = sp;
sp = push_dummy_code (current_gdbarch, sp, funaddr,
- using_gcc, args, nargs, values_type,
+ using_gcc, args, nargs, target_values_type,
&real_pc, &bp_addr, get_current_regcache ());
}
break;
param_type = TYPE_FIELD_TYPE (ftype, i);
else
param_type = NULL;
-
+
args[i] = value_arg_coerce (args[i], param_type, prototyped);
+ if (param_type != NULL && language_pass_by_reference (param_type))
+ args[i] = value_addr (args[i]);
+
/* elz: this code is to handle the case in which the function
to be called has a pointer to function as parameter and the
corresponding actual argument is the address of a function
stack, if necessary. Make certain that the value is correctly
aligned. */
- if (struct_return)
+ if (struct_return || lang_struct_return)
{
int len = TYPE_LENGTH (values_type);
if (gdbarch_inner_than (current_gdbarch, 1, 2))
}
}
+ if (lang_struct_return)
+ {
+ struct value **new_args;
+
+ /* Add the new argument to the front of the argument list. */
+ new_args = xmalloc (sizeof (struct value *) * (nargs + 1));
+ new_args[0] = value_from_pointer (lookup_pointer_type (values_type),
+ struct_addr);
+ memcpy (&new_args[1], &args[0], sizeof (struct value *) * nargs);
+ args = new_args;
+ nargs++;
+ args_cleanup = make_cleanup (xfree, args);
+ }
+ else
+ args_cleanup = make_cleanup (null_cleanup, NULL);
+
/* Create the dummy stack frame. Pass in the call dummy address as,
presumably, the ABI code knows where, in the call dummy, the
return address should be pointed. */
get_current_regcache (), bp_addr, nargs, args,
sp, struct_return, struct_addr);
+ do_cleanups (args_cleanup);
+
/* Set up a frame ID for the dummy frame so we can pass it to
set_momentary_breakpoint. We need to give the breakpoint a frame
ID so that the breakpoint code can correctly re-identify the
{
struct value *retval = NULL;
- if (TYPE_CODE (values_type) == TYPE_CODE_VOID)
+ if (lang_struct_return)
+ retval = value_at (values_type, struct_addr);
+ else if (TYPE_CODE (target_values_type) == TYPE_CODE_VOID)
{
/* If the function returns void, don't bother fetching the
return value. */
{
struct gdbarch *arch = current_gdbarch;
- switch (gdbarch_return_value (arch, values_type, NULL, NULL, NULL))
+ switch (gdbarch_return_value (arch, target_values_type, NULL, NULL, NULL))
{
case RETURN_VALUE_REGISTER_CONVENTION:
case RETURN_VALUE_ABI_RETURNS_ADDRESS:
default_word_break_characters,
c_language_arch_info,
default_print_array_index,
+ default_pass_by_reference,
LANG_MAGIC
};
return NULL;
}
+/* Return non-zero if TYPE should be passed (and returned) by
+ reference at the language level. */
+int
+language_pass_by_reference (struct type *type)
+{
+ return current_language->la_pass_by_reference (type);
+}
+
+/* Return zero; by default, types are passed by value at the language
+ level. The target ABI may pass or return some structs by reference
+ independent of this. */
+int
+default_pass_by_reference (struct type *type)
+{
+ return 0;
+}
+
/* Return the default string containing the list of characters
delimiting words. This is a reasonable default value that
most languages should be able to use. */
default_word_break_characters,
unknown_language_arch_info, /* la_language_arch_info. */
default_print_array_index,
+ default_pass_by_reference,
LANG_MAGIC
};
default_word_break_characters,
unknown_language_arch_info, /* la_language_arch_info. */
default_print_array_index,
+ default_pass_by_reference,
LANG_MAGIC
};
default_word_break_characters,
unknown_language_arch_info, /* la_language_arch_info. */
default_print_array_index,
+ default_pass_by_reference,
LANG_MAGIC
};
\f
int format,
enum val_prettyprint pretty);
+ /* Return non-zero if TYPE should be passed (and returned) by
+ reference at the language level. */
+ int (*la_pass_by_reference) (struct type *type);
+
/* Add fields above this point, so the magic number is always last. */
/* Magic number for compat checking */
int format,
enum val_prettyprint pretty);
+/* Return non-zero if TYPE should be passed (and returned) by
+ reference at the language level. */
+int language_pass_by_reference (struct type *type);
+
+/* Return zero; by default, types are passed by value at the language
+ level. The target ABI may pass or return some structs by reference
+ independent of this. */
+int default_pass_by_reference (struct type *type);
+
#endif /* defined (LANGUAGE_H) */
default_word_break_characters,
m2_language_arch_info,
default_print_array_index,
+ default_pass_by_reference,
LANG_MAGIC
};
default_word_break_characters,
c_language_arch_info,
default_print_array_index,
+ default_pass_by_reference,
LANG_MAGIC
};
default_word_break_characters,
pascal_language_arch_info,
default_print_array_index,
+ default_pass_by_reference,
LANG_MAGIC
};
default_word_break_characters,
c_language_arch_info,
default_print_array_index,
+ default_pass_by_reference,
LANG_MAGIC
};
+2007-09-23 Daniel Jacobowitz <dan@codesourcery.com>
+
+ * gdb.cp/pass-by-ref.cc, gdb.cp/pass-by-ref.exp: New files.
+
2007-09-23 Pedro Alves <pedro_alves@portugalmail.pt>
* configure.ac: Do gdb.stabs tests by default on Cygwin and MinGW
--- /dev/null
+/* This testcase is part of GDB, the GNU debugger.
+
+ Copyright 2007 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 3 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, see <http://www.gnu.org/licenses/>. */
+
+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 ()
+{
+
+}
+
+struct Derived : public Obj
+{
+ int other;
+};
+
+int blap (Derived arg)
+{
+ return foo (arg);
+}
+
+struct Container
+{
+ Obj obj;
+};
+
+int blip (Container arg)
+{
+ return foo (arg.obj);
+}
+
+Obj global_obj;
+Derived global_derived;
+Container global_container;
+
+int
+main ()
+{
+ int bar = foo (global_obj);
+ blap (global_derived);
+ blip (global_container);
+ return bar;
+}
--- /dev/null
+# Copyright 2007 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 3 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, see <http://www.gnu.org/licenses/>.
+
+# Check that GDB can call C++ functions whose parameters have
+# object type, but are passed by reference.
+
+if { [skip_cplus_tests] } { continue }
+
+set testfile "pass-by-ref"
+set srcfile ${testfile}.cc
+set binfile ${objdir}/${subdir}/${testfile}
+if { [gdb_compile "${srcdir}/${subdir}/${srcfile}" "${binfile}" \
+ executable {debug c++}] != "" } {
+ untested pass-by-ref.exp
+ 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 in obj"
+gdb_test "print blap (global_derived)" " = 3" "call function in derived"
+gdb_test "print blip (global_container)" " = 3" "call function in container"
projects / binutils-gdb.git / commitdiff