* 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

	* gdb.cp/pass-by-ref.cc, gdb.cp/pass-by-ref.exp: New files.
This commit is contained in:
Daniel Jacobowitz 2007-09-23 16:25:06 +00:00
parent 3f213f78ed
commit 41f1b6975d
18 changed files with 346 additions and 11 deletions

View File

@ -1,3 +1,31 @@
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

View File

@ -10441,6 +10441,7 @@ const struct language_defn ada_language_defn = {
ada_get_gdb_completer_word_break_characters,
ada_language_arch_info,
ada_print_array_index,
default_pass_by_reference,
LANG_MAGIC
};

View File

@ -606,6 +606,7 @@ const struct language_defn c_language_defn =
default_word_break_characters,
c_language_arch_info,
default_print_array_index,
default_pass_by_reference,
LANG_MAGIC
};
@ -711,6 +712,7 @@ const struct language_defn cplus_language_defn =
default_word_break_characters,
cplus_language_arch_info,
default_print_array_index,
cp_pass_by_reference,
LANG_MAGIC
};
@ -747,6 +749,7 @@ const struct language_defn asm_language_defn =
default_word_break_characters,
c_language_arch_info, /* FIXME: la_language_arch_info. */
default_print_array_index,
default_pass_by_reference,
LANG_MAGIC
};
@ -788,6 +791,7 @@ const struct language_defn minimal_language_defn =
default_word_break_characters,
c_language_arch_info,
default_print_array_index,
default_pass_by_reference,
LANG_MAGIC
};

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@ -135,6 +135,14 @@ cplus_method_ptr_to_value (struct value **this_p, struct value *method_ptr)
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

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@ -172,6 +172,10 @@ void cplus_make_method_ptr (gdb_byte *CONTENTS, CORE_ADDR address,
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;
@ -195,6 +199,7 @@ struct cp_abi_ops
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);
};

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@ -503,6 +503,7 @@ const struct language_defn f_language_defn =
default_word_break_characters,
f_language_arch_info,
default_print_array_index,
default_pass_by_reference,
LANG_MAGIC
};

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@ -716,6 +716,87 @@ gnuv3_skip_trampoline (struct frame_info *frame, CORE_ADDR stop_pc)
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)
{
@ -738,6 +819,7 @@ 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 */

View File

@ -339,8 +339,8 @@ call_function_by_hand (struct value *function, int nargs, struct value **args)
{
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;
@ -354,6 +354,7 @@ call_function_by_hand (struct value *function, int nargs, struct value **args)
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));
@ -460,10 +461,30 @@ call_function_by_hand (struct value *function, int nargs, struct value **args)
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. */
struct_return = using_struct_return (values_type, using_gcc);
if (language_pass_by_reference (values_type))
{
lang_struct_return = 1;
/* 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
@ -482,7 +503,7 @@ call_function_by_hand (struct value *function, int nargs, struct value **args)
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;
}
@ -490,7 +511,7 @@ call_function_by_hand (struct value *function, int nargs, struct value **args)
{
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;
@ -557,9 +578,12 @@ call_function_by_hand (struct value *function, int nargs, struct value **args)
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
@ -659,7 +683,7 @@ You must use a pointer to function type variable. Command ignored."), arg_name);
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))
@ -684,6 +708,22 @@ You must use a pointer to function type variable. Command ignored."), arg_name);
}
}
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. */
@ -691,6 +731,8 @@ You must use a pointer to function type variable. Command ignored."), arg_name);
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
@ -882,7 +924,9 @@ the function call)."), name);
{
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. */
@ -892,7 +936,7 @@ the function call)."), name);
{
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:

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@ -1115,6 +1115,7 @@ const struct language_defn java_language_defn =
default_word_break_characters,
c_language_arch_info,
default_print_array_index,
default_pass_by_reference,
LANG_MAGIC
};

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@ -1045,6 +1045,23 @@ language_class_name_from_physname (const struct language_defn *current_language,
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. */
@ -1191,6 +1208,7 @@ const struct language_defn unknown_language_defn =
default_word_break_characters,
unknown_language_arch_info, /* la_language_arch_info. */
default_print_array_index,
default_pass_by_reference,
LANG_MAGIC
};
@ -1228,6 +1246,7 @@ const struct language_defn auto_language_defn =
default_word_break_characters,
unknown_language_arch_info, /* la_language_arch_info. */
default_print_array_index,
default_pass_by_reference,
LANG_MAGIC
};
@ -1264,6 +1283,7 @@ const struct language_defn local_language_defn =
default_word_break_characters,
unknown_language_arch_info, /* la_language_arch_info. */
default_print_array_index,
default_pass_by_reference,
LANG_MAGIC
};

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@ -280,6 +280,10 @@ struct language_defn
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 */
@ -471,4 +475,13 @@ extern void default_print_array_index (struct value *index_value,
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) */

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@ -459,6 +459,7 @@ const struct language_defn m2_language_defn =
default_word_break_characters,
m2_language_arch_info,
default_print_array_index,
default_pass_by_reference,
LANG_MAGIC
};

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@ -668,6 +668,7 @@ const struct language_defn objc_language_defn = {
default_word_break_characters,
c_language_arch_info,
default_print_array_index,
default_pass_by_reference,
LANG_MAGIC
};

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@ -525,6 +525,7 @@ const struct language_defn pascal_language_defn =
default_word_break_characters,
pascal_language_arch_info,
default_print_array_index,
default_pass_by_reference,
LANG_MAGIC
};

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@ -267,6 +267,7 @@ const struct language_defn scm_language_defn =
default_word_break_characters,
c_language_arch_info,
default_print_array_index,
default_pass_by_reference,
LANG_MAGIC
};

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@ -1,3 +1,7 @@
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

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@ -0,0 +1,79 @@
/* 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;
}

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@ -0,0 +1,41 @@
# 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"