/* Low level packing and unpacking of values for GDB, the GNU Debugger.
- Copyright (C) 1986-2021 Free Software Foundation, Inc.
+ Copyright (C) 1986-2022 Free Software Foundation, Inc.
This file is part of GDB.
lazy (1),
initialized (1),
stack (0),
+ is_zero (false),
type (type_),
enclosing_type (type_)
{
used instead of read_memory to enable extra caching. */
unsigned int stack : 1;
+ /* True if this is a zero value, created by 'value_zero'; false
+ otherwise. */
+ bool is_zero : 1;
+
/* Location of value (if lval). */
union
{
LONGEST embedded_offset = 0;
LONGEST pointed_to_offset = 0;
- /* Actual contents of the value. Target byte-order. NULL or not
- valid if lazy is nonzero. */
+ /* Actual contents of the value. Target byte-order.
+
+ May be nullptr if the value is lazy or is entirely optimized out.
+ Guaranteed to be non-nullptr otherwise. */
gdb::unique_xmalloc_ptr<gdb_byte> contents;
/* Unavailable ranges in CONTENTS. We mark unavailable ranges,
struct cmd_list_element *c, const char *value)
{
if (max_value_size == -1)
- fprintf_filtered (file, _("Maximum value size is unlimited.\n"));
+ gdb_printf (file, _("Maximum value size is unlimited.\n"));
else
- fprintf_filtered (file, _("Maximum value size is %d bytes.\n"),
- max_value_size);
+ gdb_printf (file, _("Maximum value size is %d bytes.\n"),
+ max_value_size);
}
/* Called before we attempt to allocate or reallocate a buffer for the
value->parent = value_ref_ptr::new_reference (parent);
}
-gdb_byte *
+gdb::array_view<gdb_byte>
value_contents_raw (struct value *value)
{
struct gdbarch *arch = get_value_arch (value);
int unit_size = gdbarch_addressable_memory_unit_size (arch);
allocate_value_contents (value);
- return value->contents.get () + value->embedded_offset * unit_size;
+
+ ULONGEST length = TYPE_LENGTH (value_type (value));
+ return gdb::make_array_view
+ (value->contents.get () + value->embedded_offset * unit_size, length);
}
-gdb_byte *
+gdb::array_view<gdb_byte>
value_contents_all_raw (struct value *value)
{
allocate_value_contents (value);
- return value->contents.get ();
+
+ ULONGEST length = TYPE_LENGTH (value_enclosing_type (value));
+ return gdb::make_array_view (value->contents.get (), length);
}
struct type *
void
error_value_optimized_out (void)
{
- error (_("value has been optimized out"));
+ throw_error (OPTIMIZED_OUT_ERROR, _("value has been optimized out"));
}
static void
if (!value->optimized_out.empty ())
{
if (value->lval == lval_register)
- error (_("register has not been saved in frame"));
+ throw_error (OPTIMIZED_OUT_ERROR,
+ _("register has not been saved in frame"));
else
error_value_optimized_out ();
}
throw_error (NOT_AVAILABLE_ERROR, _("value is not available"));
}
-const gdb_byte *
+gdb::array_view<const gdb_byte>
value_contents_for_printing (struct value *value)
{
if (value->lazy)
value_fetch_lazy (value);
- return value->contents.get ();
+
+ ULONGEST length = TYPE_LENGTH (value_enclosing_type (value));
+ return gdb::make_array_view (value->contents.get (), length);
}
-const gdb_byte *
+gdb::array_view<const gdb_byte>
value_contents_for_printing_const (const struct value *value)
{
gdb_assert (!value->lazy);
- return value->contents.get ();
+
+ ULONGEST length = TYPE_LENGTH (value_enclosing_type (value));
+ return gdb::make_array_view (value->contents.get (), length);
}
-const gdb_byte *
+gdb::array_view<const gdb_byte>
value_contents_all (struct value *value)
{
- const gdb_byte *result = value_contents_for_printing (value);
+ gdb::array_view<const gdb_byte> result = value_contents_for_printing (value);
require_not_optimized_out (value);
require_available (value);
return result;
TARGET_CHAR_BIT * length));
/* Copy the data. */
- memcpy (value_contents_all_raw (dst) + dst_offset * unit_size,
- value_contents_all_raw (src) + src_offset * unit_size,
- length * unit_size);
+ gdb::array_view<gdb_byte> dst_contents
+ = value_contents_all_raw (dst).slice (dst_offset * unit_size,
+ length * unit_size);
+ gdb::array_view<const gdb_byte> src_contents
+ = value_contents_all_raw (src).slice (src_offset * unit_size,
+ length * unit_size);
+ copy (src_contents, dst_contents);
/* Copy the meta-data, adjusted. */
src_bit_offset = src_offset * unit_size * HOST_CHAR_BIT;
value->stack = val;
}
-const gdb_byte *
+gdb::array_view<const gdb_byte>
value_contents (struct value *value)
{
- const gdb_byte *result = value_contents_writeable (value);
+ gdb::array_view<const gdb_byte> result = value_contents_writeable (value);
require_not_optimized_out (value);
require_available (value);
return result;
}
-gdb_byte *
+gdb::array_view<gdb_byte>
value_contents_writeable (struct value *value)
{
if (value->lazy)
but it's a different block of storage. */
struct value *
-value_copy (struct value *arg)
+value_copy (const value *arg)
{
struct type *encl_type = value_enclosing_type (arg);
struct value *val;
else
val = allocate_value (encl_type);
val->type = arg->type;
- VALUE_LVAL (val) = VALUE_LVAL (arg);
+ VALUE_LVAL (val) = arg->lval;
val->location = arg->location;
val->offset = arg->offset;
val->bitpos = arg->bitpos;
val->pointed_to_offset = arg->pointed_to_offset;
val->modifiable = arg->modifiable;
val->stack = arg->stack;
+ val->is_zero = arg->is_zero;
val->initialized = arg->initialized;
- if (!value_lazy (val))
- {
- memcpy (value_contents_all_raw (val), value_contents_all_raw (arg),
- TYPE_LENGTH (value_enclosing_type (arg)));
-
- }
val->unavailable = arg->unavailable;
val->optimized_out = arg->optimized_out;
+
+ if (!value_lazy (val) && !value_entirely_optimized_out (val))
+ {
+ gdb_assert (arg->contents != nullptr);
+ ULONGEST length = TYPE_LENGTH (value_enclosing_type (arg));
+ const auto &arg_view
+ = gdb::make_array_view (arg->contents.get (), length);
+ copy (arg_view, value_contents_all_raw (val));
+ }
+
val->parent = arg->parent;
if (VALUE_LVAL (val) == lval_computed)
{
struct type *enc_type = value_enclosing_type (arg);
struct value *val = allocate_value (enc_type);
- memcpy (value_contents_all_raw (val), value_contents_all (arg),
- TYPE_LENGTH (enc_type));
+ copy (value_contents_all (arg), value_contents_all_raw (val));
val->type = arg->type;
set_value_embedded_offset (val, value_embedded_offset (arg));
set_value_pointed_to_offset (val, value_pointed_to_offset (arg));
{
gdb_assert (VALUE_LVAL (v) == not_lval);
- write_memory (addr, value_contents_raw (v), TYPE_LENGTH (value_type (v)));
+ write_memory (addr, value_contents_raw (v).data (), TYPE_LENGTH (value_type (v)));
v->lval = lval_memory;
v->location.address = addr;
}
return value_copy (value_history[absnum].get ());
}
+/* See value.h. */
+
+ULONGEST
+value_history_count ()
+{
+ return value_history.size ();
+}
+
static void
show_values (const char *num_exp, int from_tty)
{
struct value_print_options opts;
val = access_value_history (i);
- printf_filtered (("$%d = "), i);
+ gdb_printf (("$%d = "), i);
get_user_print_options (&opts);
value_print (val, gdb_stdout, &opts);
- printf_filtered (("\n"));
+ gdb_printf (("\n"));
}
/* The next "show values +" should start after what we just printed. */
switch (var->kind)
{
case INTERNALVAR_VALUE:
- addr = value_contents_writeable (var->u.value);
+ addr = value_contents_writeable (var->u.value).data ();
arch = get_value_arch (var->u.value);
unit_size = gdbarch_addressable_memory_unit_size (arch);
modify_field (value_type (var->u.value), addr + offset,
value_as_long (newval), bitpos, bitsize);
else
- memcpy (addr + offset * unit_size, value_contents (newval),
+ memcpy (addr + offset * unit_size, value_contents (newval).data (),
TYPE_LENGTH (value_type (newval)));
break;
xfree (var->u.string);
break;
- case INTERNALVAR_MAKE_VALUE:
- if (var->u.make_value.functions->destroy != NULL)
- var->u.make_value.functions->destroy (var->u.make_value.data);
- break;
-
default:
break;
}
{
varseen = 1;
}
- printf_filtered (("$%s = "), var->name);
+ gdb_printf (("$%s = "), var->name);
try
{
_("<error: %s>"), ex.what ());
}
- printf_filtered (("\n"));
+ gdb_printf (("\n"));
}
if (!varseen)
{
The user can't create them except via Python, and if Python support
is installed this message will never be printed ($_streq will
exist). */
- printf_unfiltered (_("No debugger convenience variables now defined.\n"
- "Convenience variables have "
- "names starting with \"$\";\n"
- "use \"set\" as in \"set "
- "$foo = 5\" to define them.\n"));
+ gdb_printf (_("No debugger convenience variables now defined.\n"
+ "Convenience variables have "
+ "names starting with \"$\";\n"
+ "use \"set\" as in \"set "
+ "$foo = 5\" to define them.\n"));
}
}
\f
in disassemble_command). It also dereferences references, which
I suspect is the most logical thing to do. */
val = coerce_array (val);
- return unpack_long (value_type (val), value_contents (val));
+ return unpack_long (value_type (val), value_contents (val).data ());
}
/* Extract a value as a C pointer. Does not deallocate the value.
if (!value_type (val)->is_pointer_or_reference ()
&& gdbarch_integer_to_address_p (gdbarch))
return gdbarch_integer_to_address (gdbarch, value_type (val),
- value_contents (val));
+ value_contents (val).data ());
- return unpack_long (value_type (val), value_contents (val));
+ return unpack_long (value_type (val), value_contents (val).data ());
#endif
}
\f
if (is_floating_type (type))
{
- if (!target_float_is_valid (value_contents (val), type))
+ if (!target_float_is_valid (value_contents (val).data (), type))
error (_("Invalid floating value found in program."));
return true;
}
{
struct value *retval;
- switch (TYPE_FIELD_LOC_KIND (type, fieldno))
+ switch (type->field (fieldno).loc_kind ())
{
case FIELD_LOC_KIND_PHYSADDR:
retval = value_at_lazy (type->field (fieldno).type (),
- TYPE_FIELD_STATIC_PHYSADDR (type, fieldno));
+ type->field (fieldno).loc_physaddr ());
break;
case FIELD_LOC_KIND_PHYSNAME:
{
- const char *phys_name = TYPE_FIELD_STATIC_PHYSNAME (type, fieldno);
+ const char *phys_name = type->field (fieldno).loc_physname ();
/* type->field (fieldno).name (); */
struct block_symbol sym = lookup_symbol (phys_name, 0, VAR_DOMAIN, 0);
if (!msym.minsym)
retval = allocate_optimized_out_value (field_type);
else
- retval = value_at_lazy (field_type, BMSYMBOL_VALUE_ADDRESS (msym));
+ retval = value_at_lazy (field_type, msym.value_address ());
}
else
retval = value_of_variable (sym.symbol, sym.block);
bit. Assume that the address, offset, and embedded offset
are sufficiently aligned. */
- LONGEST bitpos = TYPE_FIELD_BITPOS (arg_type, fieldno);
+ LONGEST bitpos = arg_type->field (fieldno).loc_bitpos ();
LONGEST container_bitsize = TYPE_LENGTH (type) * 8;
v = allocate_value_lazy (type);
for references to ordinary fields of unavailable values. */
if (BASETYPE_VIA_VIRTUAL (arg_type, fieldno))
boffset = baseclass_offset (arg_type, fieldno,
- value_contents (arg1),
+ value_contents (arg1).data (),
value_embedded_offset (arg1),
value_address (arg1),
arg1);
else
- boffset = TYPE_FIELD_BITPOS (arg_type, fieldno) / 8;
+ boffset = arg_type->field (fieldno).loc_bitpos () / 8;
if (value_lazy (arg1))
v = allocate_value_lazy (value_enclosing_type (arg1));
else
{
/* Plain old data member */
- offset += (TYPE_FIELD_BITPOS (arg_type, fieldno)
+ offset += (arg_type->field (fieldno).loc_bitpos ()
/ (HOST_CHAR_BIT * unit_size));
/* Lazy register values with offsets are not supported. */
struct bound_minimal_symbol msym;
sym = lookup_symbol (physname, 0, VAR_DOMAIN, 0).symbol;
- if (sym != NULL)
- {
- memset (&msym, 0, sizeof (msym));
- }
- else
+ if (sym == nullptr)
{
- gdb_assert (sym == NULL);
msym = lookup_bound_minimal_symbol (physname);
if (msym.minsym == NULL)
return NULL;
VALUE_LVAL (v) = lval_memory;
if (sym)
{
- set_value_address (v, BLOCK_ENTRY_PC (SYMBOL_BLOCK_VALUE (sym)));
+ set_value_address (v, sym->value_block ()->entry_pc ());
}
else
{
set_value_address (v,
gdbarch_convert_from_func_ptr_addr
- (gdbarch, BMSYMBOL_VALUE_ADDRESS (msym),
+ (gdbarch, msym.value_address (),
current_inferior ()->top_target ()));
}
LONGEST embedded_offset, int fieldno,
const struct value *val, LONGEST *result)
{
- int bitpos = TYPE_FIELD_BITPOS (type, fieldno);
+ int bitpos = type->field (fieldno).loc_bitpos ();
int bitsize = TYPE_FIELD_BITSIZE (type, fieldno);
struct type *field_type = type->field (fieldno).type ();
int bit_offset;
LONGEST
unpack_field_as_long (struct type *type, const gdb_byte *valaddr, int fieldno)
{
- int bitpos = TYPE_FIELD_BITPOS (type, fieldno);
+ int bitpos = type->field (fieldno).loc_bitpos ();
int bitsize = TYPE_FIELD_BITSIZE (type, fieldno);
struct type *field_type = type->field (fieldno).type ();
num = unpack_bits_as_long (field_type, valaddr + embedded_offset,
bitpos, bitsize);
- store_signed_integer (value_contents_raw (dest_val),
+ store_signed_integer (value_contents_raw (dest_val).data (),
TYPE_LENGTH (field_type), byte_order, num);
}
const gdb_byte *valaddr,
LONGEST embedded_offset, const struct value *val)
{
- int bitpos = TYPE_FIELD_BITPOS (type, fieldno);
+ int bitpos = type->field (fieldno).loc_bitpos ();
int bitsize = TYPE_FIELD_BITSIZE (type, fieldno);
struct value *res_val = allocate_value (type->field (fieldno).type ());
}
+/* Create a value of type TYPE that is zero, and return it. */
+
+struct value *
+value_zero (struct type *type, enum lval_type lv)
+{
+ struct value *val = allocate_value_lazy (type);
+
+ VALUE_LVAL (val) = (lv == lval_computed ? not_lval : lv);
+ val->is_zero = true;
+ return val;
+}
+
/* Convert C numbers into newly allocated values. */
struct value *
{
struct value *val = allocate_value (type);
- pack_long (value_contents_raw (val), type, num);
+ pack_long (value_contents_raw (val).data (), type, num);
return val;
}
{
struct value *val = allocate_value (type);
- pack_unsigned_long (value_contents_raw (val), type, num);
+ pack_unsigned_long (value_contents_raw (val).data (), type, num);
return val;
}
{
struct value *val = allocate_value (type);
- store_typed_address (value_contents_raw (val),
+ store_typed_address (value_contents_raw (val).data (),
check_typedef (type), addr);
return val;
}
{
struct value *value = allocate_value (type);
gdb_assert (type->code () == TYPE_CODE_FLT);
- target_float_from_host_double (value_contents_raw (value),
+ target_float_from_host_double (value_contents_raw (value).data (),
value_type (value), d);
return value;
}
struct value *result;
result = allocate_value (type);
- memcpy (value_contents_raw (result), contents, TYPE_LENGTH (type));
+ memcpy (value_contents_raw (result).data (), contents, TYPE_LENGTH (type));
return result;
}
enc_type = check_typedef (value_enclosing_type (arg));
enc_type = TYPE_TARGET_TYPE (enc_type);
- CORE_ADDR addr = unpack_pointer (value_type (arg), value_contents (arg));
+ CORE_ADDR addr = unpack_pointer (value_type (arg), value_contents (arg).data ());
retval = value_at_lazy (enc_type, addr);
enc_type = value_type (retval);
return readjust_indirect_value_type (retval, enc_type, value_type_arg_tmp,
value_fetch_lazy (parent);
unpack_value_bitfield (val, value_bitpos (val), value_bitsize (val),
- value_contents_for_printing (parent),
+ value_contents_for_printing (parent).data (),
value_offset (val), parent);
}
if (TYPE_LENGTH (type))
read_value_memory (val, 0, value_stack (val),
- addr, value_contents_all_raw (val),
+ addr, value_contents_all_raw (val).data (),
type_length_units (type));
}
gdbarch = get_frame_arch (frame);
string_file debug_file;
- fprintf_unfiltered (&debug_file,
- "(frame=%d, regnum=%d(%s), ...) ",
- frame_relative_level (frame), regnum,
- user_reg_map_regnum_to_name (gdbarch, regnum));
+ gdb_printf (&debug_file,
+ "(frame=%d, regnum=%d(%s), ...) ",
+ frame_relative_level (frame), regnum,
+ user_reg_map_regnum_to_name (gdbarch, regnum));
- fprintf_unfiltered (&debug_file, "->");
+ gdb_printf (&debug_file, "->");
if (value_optimized_out (new_val))
{
- fprintf_unfiltered (&debug_file, " ");
+ gdb_printf (&debug_file, " ");
val_print_optimized_out (new_val, &debug_file);
}
else
{
int i;
- const gdb_byte *buf = value_contents (new_val);
+ gdb::array_view<const gdb_byte> buf = value_contents (new_val);
if (VALUE_LVAL (new_val) == lval_register)
- fprintf_unfiltered (&debug_file, " register=%d",
- VALUE_REGNUM (new_val));
+ gdb_printf (&debug_file, " register=%d",
+ VALUE_REGNUM (new_val));
else if (VALUE_LVAL (new_val) == lval_memory)
- fprintf_unfiltered (&debug_file, " address=%s",
- paddress (gdbarch,
- value_address (new_val)));
+ gdb_printf (&debug_file, " address=%s",
+ paddress (gdbarch,
+ value_address (new_val)));
else
- fprintf_unfiltered (&debug_file, " computed");
+ gdb_printf (&debug_file, " computed");
- fprintf_unfiltered (&debug_file, " bytes=");
- fprintf_unfiltered (&debug_file, "[");
+ gdb_printf (&debug_file, " bytes=");
+ gdb_printf (&debug_file, "[");
for (i = 0; i < register_size (gdbarch, regnum); i++)
- fprintf_unfiltered (&debug_file, "%02x", buf[i]);
- fprintf_unfiltered (&debug_file, "]");
+ gdb_printf (&debug_file, "%02x", buf[i]);
+ gdb_printf (&debug_file, "]");
}
frame_debug_printf ("%s", debug_file.c_str ());
value. */
gdb_assert (val->optimized_out.empty ());
gdb_assert (val->unavailable.empty ());
- if (value_bitsize (val))
+ if (val->is_zero)
+ {
+ /* Nothing. */
+ }
+ else if (value_bitsize (val))
value_fetch_lazy_bitfield (val);
else if (VALUE_LVAL (val) == lval_memory)
value_fetch_lazy_memory (val);
}
}
+static void
+test_value_copy ()
+{
+ type *type = builtin_type (current_inferior ()->gdbarch)->builtin_int;
+
+ /* Verify that we can copy an entirely optimized out value, that may not have
+ its contents allocated. */
+ value_ref_ptr val = release_value (allocate_optimized_out_value (type));
+ value_ref_ptr copy = release_value (value_copy (val.get ()));
+
+ SELF_CHECK (value_entirely_optimized_out (val.get ()));
+ SELF_CHECK (value_entirely_optimized_out (copy.get ()));
+}
+
} /* namespace selftests */
#endif /* GDB_SELF_TEST */
set_max_value_size,
show_max_value_size,
&setlist, &showlist);
+ set_show_commands vsize_limit
+ = add_setshow_zuinteger_unlimited_cmd ("varsize-limit", class_support,
+ &max_value_size, _("\
+Set the maximum number of bytes allowed in a variable-size object."), _("\
+Show the maximum number of bytes allowed in a variable-size object."), _("\
+Attempts to access an object whose size is not a compile-time constant\n\
+and exceeds this limit will cause an error."),
+ NULL, NULL, &setlist, &showlist);
+ deprecate_cmd (vsize_limit.set, "set max-value-size");
+
#if GDB_SELF_TEST
selftests::register_test ("ranges_contain", selftests::test_ranges_contain);
selftests::register_test ("insert_into_bit_range_vector",
selftests::test_insert_into_bit_range_vector);
+ selftests::register_test ("value_copy", selftests::test_value_copy);
#endif
}