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- /* Perform non-arithmetic operations on values, for GDB.
- Copyright (C) 1986-2022 Free Software Foundation, Inc.
- This file is part of GDB.
- 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/>. */
- #include "defs.h"
- #include "symtab.h"
- #include "gdbtypes.h"
- #include "value.h"
- #include "frame.h"
- #include "inferior.h"
- #include "gdbcore.h"
- #include "target.h"
- #include "demangle.h"
- #include "language.h"
- #include "gdbcmd.h"
- #include "regcache.h"
- #include "cp-abi.h"
- #include "block.h"
- #include "infcall.h"
- #include "dictionary.h"
- #include "cp-support.h"
- #include "target-float.h"
- #include "tracepoint.h"
- #include "observable.h"
- #include "objfiles.h"
- #include "extension.h"
- #include "gdbtypes.h"
- #include "gdbsupport/byte-vector.h"
- /* Local functions. */
- static int typecmp (bool staticp, bool varargs, int nargs,
- struct field t1[], const gdb::array_view<value *> t2);
- static struct value *search_struct_field (const char *, struct value *,
- struct type *, int);
- static struct value *search_struct_method (const char *, struct value **,
- gdb::optional<gdb::array_view<value *>>,
- LONGEST, int *, struct type *);
- static int find_oload_champ_namespace (gdb::array_view<value *> args,
- const char *, const char *,
- std::vector<symbol *> *oload_syms,
- badness_vector *,
- const int no_adl);
- static int find_oload_champ_namespace_loop (gdb::array_view<value *> args,
- const char *, const char *,
- int, std::vector<symbol *> *oload_syms,
- badness_vector *, int *,
- const int no_adl);
- static int find_oload_champ (gdb::array_view<value *> args,
- size_t num_fns,
- fn_field *methods,
- xmethod_worker_up *xmethods,
- symbol **functions,
- badness_vector *oload_champ_bv);
- static int oload_method_static_p (struct fn_field *, int);
- enum oload_classification { STANDARD, NON_STANDARD, INCOMPATIBLE };
- static enum oload_classification classify_oload_match
- (const badness_vector &, int, int);
- static struct value *value_struct_elt_for_reference (struct type *,
- int, struct type *,
- const char *,
- struct type *,
- int, enum noside);
- static struct value *value_namespace_elt (const struct type *,
- const char *, int , enum noside);
- static struct value *value_maybe_namespace_elt (const struct type *,
- const char *, int,
- enum noside);
- static CORE_ADDR allocate_space_in_inferior (int);
- static struct value *cast_into_complex (struct type *, struct value *);
- bool overload_resolution = false;
- static void
- show_overload_resolution (struct ui_file *file, int from_tty,
- struct cmd_list_element *c,
- const char *value)
- {
- gdb_printf (file, _("Overload resolution in evaluating "
- "C++ functions is %s.\n"),
- value);
- }
- /* Find the address of function name NAME in the inferior. If OBJF_P
- is non-NULL, *OBJF_P will be set to the OBJFILE where the function
- is defined. */
- struct value *
- find_function_in_inferior (const char *name, struct objfile **objf_p)
- {
- struct block_symbol sym;
- sym = lookup_symbol (name, 0, VAR_DOMAIN, 0);
- if (sym.symbol != NULL)
- {
- if (sym.symbol->aclass () != LOC_BLOCK)
- {
- error (_("\"%s\" exists in this program but is not a function."),
- name);
- }
- if (objf_p)
- *objf_p = symbol_objfile (sym.symbol);
- return value_of_variable (sym.symbol, sym.block);
- }
- else
- {
- struct bound_minimal_symbol msymbol =
- lookup_bound_minimal_symbol (name);
- if (msymbol.minsym != NULL)
- {
- struct objfile *objfile = msymbol.objfile;
- struct gdbarch *gdbarch = objfile->arch ();
- struct type *type;
- CORE_ADDR maddr;
- type = lookup_pointer_type (builtin_type (gdbarch)->builtin_char);
- type = lookup_function_type (type);
- type = lookup_pointer_type (type);
- maddr = BMSYMBOL_VALUE_ADDRESS (msymbol);
- if (objf_p)
- *objf_p = objfile;
- return value_from_pointer (type, maddr);
- }
- else
- {
- if (!target_has_execution ())
- error (_("evaluation of this expression "
- "requires the target program to be active"));
- else
- error (_("evaluation of this expression requires the "
- "program to have a function \"%s\"."),
- name);
- }
- }
- }
- /* Allocate NBYTES of space in the inferior using the inferior's
- malloc and return a value that is a pointer to the allocated
- space. */
- struct value *
- value_allocate_space_in_inferior (int len)
- {
- struct objfile *objf;
- struct value *val = find_function_in_inferior ("malloc", &objf);
- struct gdbarch *gdbarch = objf->arch ();
- struct value *blocklen;
- blocklen = value_from_longest (builtin_type (gdbarch)->builtin_int, len);
- val = call_function_by_hand (val, NULL, blocklen);
- if (value_logical_not (val))
- {
- if (!target_has_execution ())
- error (_("No memory available to program now: "
- "you need to start the target first"));
- else
- error (_("No memory available to program: call to malloc failed"));
- }
- return val;
- }
- static CORE_ADDR
- allocate_space_in_inferior (int len)
- {
- return value_as_long (value_allocate_space_in_inferior (len));
- }
- /* Cast struct value VAL to type TYPE and return as a value.
- Both type and val must be of TYPE_CODE_STRUCT or TYPE_CODE_UNION
- for this to work. Typedef to one of the codes is permitted.
- Returns NULL if the cast is neither an upcast nor a downcast. */
- static struct value *
- value_cast_structs (struct type *type, struct value *v2)
- {
- struct type *t1;
- struct type *t2;
- struct value *v;
- gdb_assert (type != NULL && v2 != NULL);
- t1 = check_typedef (type);
- t2 = check_typedef (value_type (v2));
- /* Check preconditions. */
- gdb_assert ((t1->code () == TYPE_CODE_STRUCT
- || t1->code () == TYPE_CODE_UNION)
- && !!"Precondition is that type is of STRUCT or UNION kind.");
- gdb_assert ((t2->code () == TYPE_CODE_STRUCT
- || t2->code () == TYPE_CODE_UNION)
- && !!"Precondition is that value is of STRUCT or UNION kind");
- if (t1->name () != NULL
- && t2->name () != NULL
- && !strcmp (t1->name (), t2->name ()))
- return NULL;
- /* Upcasting: look in the type of the source to see if it contains the
- type of the target as a superclass. If so, we'll need to
- offset the pointer rather than just change its type. */
- if (t1->name () != NULL)
- {
- v = search_struct_field (t1->name (),
- v2, t2, 1);
- if (v)
- return v;
- }
- /* Downcasting: look in the type of the target to see if it contains the
- type of the source as a superclass. If so, we'll need to
- offset the pointer rather than just change its type. */
- if (t2->name () != NULL)
- {
- /* Try downcasting using the run-time type of the value. */
- int full, using_enc;
- LONGEST top;
- struct type *real_type;
- real_type = value_rtti_type (v2, &full, &top, &using_enc);
- if (real_type)
- {
- v = value_full_object (v2, real_type, full, top, using_enc);
- v = value_at_lazy (real_type, value_address (v));
- real_type = value_type (v);
- /* We might be trying to cast to the outermost enclosing
- type, in which case search_struct_field won't work. */
- if (real_type->name () != NULL
- && !strcmp (real_type->name (), t1->name ()))
- return v;
- v = search_struct_field (t2->name (), v, real_type, 1);
- if (v)
- return v;
- }
- /* Try downcasting using information from the destination type
- T2. This wouldn't work properly for classes with virtual
- bases, but those were handled above. */
- v = search_struct_field (t2->name (),
- value_zero (t1, not_lval), t1, 1);
- if (v)
- {
- /* Downcasting is possible (t1 is superclass of v2). */
- CORE_ADDR addr2 = value_address (v2);
- addr2 -= value_address (v) + value_embedded_offset (v);
- return value_at (type, addr2);
- }
- }
- return NULL;
- }
- /* Cast one pointer or reference type to another. Both TYPE and
- the type of ARG2 should be pointer types, or else both should be
- reference types. If SUBCLASS_CHECK is non-zero, this will force a
- check to see whether TYPE is a superclass of ARG2's type. If
- SUBCLASS_CHECK is zero, then the subclass check is done only when
- ARG2 is itself non-zero. Returns the new pointer or reference. */
- struct value *
- value_cast_pointers (struct type *type, struct value *arg2,
- int subclass_check)
- {
- struct type *type1 = check_typedef (type);
- struct type *type2 = check_typedef (value_type (arg2));
- struct type *t1 = check_typedef (TYPE_TARGET_TYPE (type1));
- struct type *t2 = check_typedef (TYPE_TARGET_TYPE (type2));
- if (t1->code () == TYPE_CODE_STRUCT
- && t2->code () == TYPE_CODE_STRUCT
- && (subclass_check || !value_logical_not (arg2)))
- {
- struct value *v2;
- if (TYPE_IS_REFERENCE (type2))
- v2 = coerce_ref (arg2);
- else
- v2 = value_ind (arg2);
- gdb_assert (check_typedef (value_type (v2))->code ()
- == TYPE_CODE_STRUCT && !!"Why did coercion fail?");
- v2 = value_cast_structs (t1, v2);
- /* At this point we have what we can have, un-dereference if needed. */
- if (v2)
- {
- struct value *v = value_addr (v2);
- deprecated_set_value_type (v, type);
- return v;
- }
- }
- /* No superclass found, just change the pointer type. */
- arg2 = value_copy (arg2);
- deprecated_set_value_type (arg2, type);
- set_value_enclosing_type (arg2, type);
- set_value_pointed_to_offset (arg2, 0); /* pai: chk_val */
- return arg2;
- }
- /* See value.h. */
- gdb_mpq
- value_to_gdb_mpq (struct value *value)
- {
- struct type *type = check_typedef (value_type (value));
- gdb_mpq result;
- if (is_floating_type (type))
- {
- double d = target_float_to_host_double (value_contents (value).data (),
- type);
- mpq_set_d (result.val, d);
- }
- else
- {
- gdb_assert (is_integral_type (type)
- || is_fixed_point_type (type));
- gdb_mpz vz;
- vz.read (value_contents (value), type_byte_order (type),
- type->is_unsigned ());
- mpq_set_z (result.val, vz.val);
- if (is_fixed_point_type (type))
- mpq_mul (result.val, result.val,
- type->fixed_point_scaling_factor ().val);
- }
- return result;
- }
- /* Assuming that TO_TYPE is a fixed point type, return a value
- corresponding to the cast of FROM_VAL to that type. */
- static struct value *
- value_cast_to_fixed_point (struct type *to_type, struct value *from_val)
- {
- struct type *from_type = value_type (from_val);
- if (from_type == to_type)
- return from_val;
- if (!is_floating_type (from_type)
- && !is_integral_type (from_type)
- && !is_fixed_point_type (from_type))
- error (_("Invalid conversion from type %s to fixed point type %s"),
- from_type->name (), to_type->name ());
- gdb_mpq vq = value_to_gdb_mpq (from_val);
- /* Divide that value by the scaling factor to obtain the unscaled
- value, first in rational form, and then in integer form. */
- mpq_div (vq.val, vq.val, to_type->fixed_point_scaling_factor ().val);
- gdb_mpz unscaled = vq.get_rounded ();
- /* Finally, create the result value, and pack the unscaled value
- in it. */
- struct value *result = allocate_value (to_type);
- unscaled.write (value_contents_raw (result),
- type_byte_order (to_type),
- to_type->is_unsigned ());
- return result;
- }
- /* Cast value ARG2 to type TYPE and return as a value.
- More general than a C cast: accepts any two types of the same length,
- and if ARG2 is an lvalue it can be cast into anything at all. */
- /* In C++, casts may change pointer or object representations. */
- struct value *
- value_cast (struct type *type, struct value *arg2)
- {
- enum type_code code1;
- enum type_code code2;
- int scalar;
- struct type *type2;
- int convert_to_boolean = 0;
- /* TYPE might be equal in meaning to the existing type of ARG2, but for
- many reasons, might be a different type object (e.g. TYPE might be a
- gdbarch owned type, while VALUE_TYPE (ARG2) could be an objfile owned
- type).
- In this case we want to preserve the LVAL of ARG2 as this allows the
- resulting value to be used in more places. We do this by calling
- VALUE_COPY if appropriate. */
- if (types_deeply_equal (value_type (arg2), type))
- {
- /* If the types are exactly equal then we can avoid creating a new
- value completely. */
- if (value_type (arg2) != type)
- {
- arg2 = value_copy (arg2);
- deprecated_set_value_type (arg2, type);
- }
- return arg2;
- }
- if (is_fixed_point_type (type))
- return value_cast_to_fixed_point (type, arg2);
- /* Check if we are casting struct reference to struct reference. */
- if (TYPE_IS_REFERENCE (check_typedef (type)))
- {
- /* We dereference type; then we recurse and finally
- we generate value of the given reference. Nothing wrong with
- that. */
- struct type *t1 = check_typedef (type);
- struct type *dereftype = check_typedef (TYPE_TARGET_TYPE (t1));
- struct value *val = value_cast (dereftype, arg2);
- return value_ref (val, t1->code ());
- }
- if (TYPE_IS_REFERENCE (check_typedef (value_type (arg2))))
- /* We deref the value and then do the cast. */
- return value_cast (type, coerce_ref (arg2));
- /* Strip typedefs / resolve stubs in order to get at the type's
- code/length, but remember the original type, to use as the
- resulting type of the cast, in case it was a typedef. */
- struct type *to_type = type;
- type = check_typedef (type);
- code1 = type->code ();
- arg2 = coerce_ref (arg2);
- type2 = check_typedef (value_type (arg2));
- /* You can't cast to a reference type. See value_cast_pointers
- instead. */
- gdb_assert (!TYPE_IS_REFERENCE (type));
- /* A cast to an undetermined-length array_type, such as
- (TYPE [])OBJECT, is treated like a cast to (TYPE [N])OBJECT,
- where N is sizeof(OBJECT)/sizeof(TYPE). */
- if (code1 == TYPE_CODE_ARRAY)
- {
- struct type *element_type = TYPE_TARGET_TYPE (type);
- unsigned element_length = TYPE_LENGTH (check_typedef (element_type));
- if (element_length > 0 && type->bounds ()->high.kind () == PROP_UNDEFINED)
- {
- struct type *range_type = type->index_type ();
- int val_length = TYPE_LENGTH (type2);
- LONGEST low_bound, high_bound, new_length;
- if (!get_discrete_bounds (range_type, &low_bound, &high_bound))
- low_bound = 0, high_bound = 0;
- new_length = val_length / element_length;
- if (val_length % element_length != 0)
- warning (_("array element type size does not "
- "divide object size in cast"));
- /* FIXME-type-allocation: need a way to free this type when
- we are done with it. */
- range_type = create_static_range_type (NULL,
- TYPE_TARGET_TYPE (range_type),
- low_bound,
- new_length + low_bound - 1);
- deprecated_set_value_type (arg2,
- create_array_type (NULL,
- element_type,
- range_type));
- return arg2;
- }
- }
- if (current_language->c_style_arrays_p ()
- && type2->code () == TYPE_CODE_ARRAY
- && !type2->is_vector ())
- arg2 = value_coerce_array (arg2);
- if (type2->code () == TYPE_CODE_FUNC)
- arg2 = value_coerce_function (arg2);
- type2 = check_typedef (value_type (arg2));
- code2 = type2->code ();
- if (code1 == TYPE_CODE_COMPLEX)
- return cast_into_complex (to_type, arg2);
- if (code1 == TYPE_CODE_BOOL)
- {
- code1 = TYPE_CODE_INT;
- convert_to_boolean = 1;
- }
- if (code1 == TYPE_CODE_CHAR)
- code1 = TYPE_CODE_INT;
- if (code2 == TYPE_CODE_BOOL || code2 == TYPE_CODE_CHAR)
- code2 = TYPE_CODE_INT;
- scalar = (code2 == TYPE_CODE_INT || code2 == TYPE_CODE_FLT
- || code2 == TYPE_CODE_DECFLOAT || code2 == TYPE_CODE_ENUM
- || code2 == TYPE_CODE_RANGE
- || is_fixed_point_type (type2));
- if ((code1 == TYPE_CODE_STRUCT || code1 == TYPE_CODE_UNION)
- && (code2 == TYPE_CODE_STRUCT || code2 == TYPE_CODE_UNION)
- && type->name () != 0)
- {
- struct value *v = value_cast_structs (to_type, arg2);
- if (v)
- return v;
- }
- if (is_floating_type (type) && scalar)
- {
- if (is_floating_value (arg2))
- {
- struct value *v = allocate_value (to_type);
- target_float_convert (value_contents (arg2).data (), type2,
- value_contents_raw (v).data (), type);
- return v;
- }
- else if (is_fixed_point_type (type2))
- {
- gdb_mpq fp_val;
- fp_val.read_fixed_point (value_contents (arg2),
- type_byte_order (type2),
- type2->is_unsigned (),
- type2->fixed_point_scaling_factor ());
- struct value *v = allocate_value (to_type);
- target_float_from_host_double (value_contents_raw (v).data (),
- to_type, mpq_get_d (fp_val.val));
- return v;
- }
- /* The only option left is an integral type. */
- if (type2->is_unsigned ())
- return value_from_ulongest (to_type, value_as_long (arg2));
- else
- return value_from_longest (to_type, value_as_long (arg2));
- }
- else if ((code1 == TYPE_CODE_INT || code1 == TYPE_CODE_ENUM
- || code1 == TYPE_CODE_RANGE)
- && (scalar || code2 == TYPE_CODE_PTR
- || code2 == TYPE_CODE_MEMBERPTR))
- {
- LONGEST longest;
- /* When we cast pointers to integers, we mustn't use
- gdbarch_pointer_to_address to find the address the pointer
- represents, as value_as_long would. GDB should evaluate
- expressions just as the compiler would --- and the compiler
- sees a cast as a simple reinterpretation of the pointer's
- bits. */
- if (code2 == TYPE_CODE_PTR)
- longest = extract_unsigned_integer
- (value_contents (arg2), type_byte_order (type2));
- else
- longest = value_as_long (arg2);
- return value_from_longest (to_type, convert_to_boolean ?
- (LONGEST) (longest ? 1 : 0) : longest);
- }
- else if (code1 == TYPE_CODE_PTR && (code2 == TYPE_CODE_INT
- || code2 == TYPE_CODE_ENUM
- || code2 == TYPE_CODE_RANGE))
- {
- /* TYPE_LENGTH (type) is the length of a pointer, but we really
- want the length of an address! -- we are really dealing with
- addresses (i.e., gdb representations) not pointers (i.e.,
- target representations) here.
- This allows things like "print *(int *)0x01000234" to work
- without printing a misleading message -- which would
- otherwise occur when dealing with a target having two byte
- pointers and four byte addresses. */
- int addr_bit = gdbarch_addr_bit (type2->arch ());
- LONGEST longest = value_as_long (arg2);
- if (addr_bit < sizeof (LONGEST) * HOST_CHAR_BIT)
- {
- if (longest >= ((LONGEST) 1 << addr_bit)
- || longest <= -((LONGEST) 1 << addr_bit))
- warning (_("value truncated"));
- }
- return value_from_longest (to_type, longest);
- }
- else if (code1 == TYPE_CODE_METHODPTR && code2 == TYPE_CODE_INT
- && value_as_long (arg2) == 0)
- {
- struct value *result = allocate_value (to_type);
- cplus_make_method_ptr (to_type,
- value_contents_writeable (result).data (), 0, 0);
- return result;
- }
- else if (code1 == TYPE_CODE_MEMBERPTR && code2 == TYPE_CODE_INT
- && value_as_long (arg2) == 0)
- {
- /* The Itanium C++ ABI represents NULL pointers to members as
- minus one, instead of biasing the normal case. */
- return value_from_longest (to_type, -1);
- }
- else if (code1 == TYPE_CODE_ARRAY && type->is_vector ()
- && code2 == TYPE_CODE_ARRAY && type2->is_vector ()
- && TYPE_LENGTH (type) != TYPE_LENGTH (type2))
- error (_("Cannot convert between vector values of different sizes"));
- else if (code1 == TYPE_CODE_ARRAY && type->is_vector () && scalar
- && TYPE_LENGTH (type) != TYPE_LENGTH (type2))
- error (_("can only cast scalar to vector of same size"));
- else if (code1 == TYPE_CODE_VOID)
- {
- return value_zero (to_type, not_lval);
- }
- else if (TYPE_LENGTH (type) == TYPE_LENGTH (type2))
- {
- if (code1 == TYPE_CODE_PTR && code2 == TYPE_CODE_PTR)
- return value_cast_pointers (to_type, arg2, 0);
- arg2 = value_copy (arg2);
- deprecated_set_value_type (arg2, to_type);
- set_value_enclosing_type (arg2, to_type);
- set_value_pointed_to_offset (arg2, 0); /* pai: chk_val */
- return arg2;
- }
- else if (VALUE_LVAL (arg2) == lval_memory)
- return value_at_lazy (to_type, value_address (arg2));
- else
- {
- if (current_language->la_language == language_ada)
- error (_("Invalid type conversion."));
- error (_("Invalid cast."));
- }
- }
- /* The C++ reinterpret_cast operator. */
- struct value *
- value_reinterpret_cast (struct type *type, struct value *arg)
- {
- struct value *result;
- struct type *real_type = check_typedef (type);
- struct type *arg_type, *dest_type;
- int is_ref = 0;
- enum type_code dest_code, arg_code;
- /* Do reference, function, and array conversion. */
- arg = coerce_array (arg);
- /* Attempt to preserve the type the user asked for. */
- dest_type = type;
- /* If we are casting to a reference type, transform
- reinterpret_cast<T&[&]>(V) to *reinterpret_cast<T*>(&V). */
- if (TYPE_IS_REFERENCE (real_type))
- {
- is_ref = 1;
- arg = value_addr (arg);
- dest_type = lookup_pointer_type (TYPE_TARGET_TYPE (dest_type));
- real_type = lookup_pointer_type (real_type);
- }
- arg_type = value_type (arg);
- dest_code = real_type->code ();
- arg_code = arg_type->code ();
- /* We can convert pointer types, or any pointer type to int, or int
- type to pointer. */
- if ((dest_code == TYPE_CODE_PTR && arg_code == TYPE_CODE_INT)
- || (dest_code == TYPE_CODE_INT && arg_code == TYPE_CODE_PTR)
- || (dest_code == TYPE_CODE_METHODPTR && arg_code == TYPE_CODE_INT)
- || (dest_code == TYPE_CODE_INT && arg_code == TYPE_CODE_METHODPTR)
- || (dest_code == TYPE_CODE_MEMBERPTR && arg_code == TYPE_CODE_INT)
- || (dest_code == TYPE_CODE_INT && arg_code == TYPE_CODE_MEMBERPTR)
- || (dest_code == arg_code
- && (dest_code == TYPE_CODE_PTR
- || dest_code == TYPE_CODE_METHODPTR
- || dest_code == TYPE_CODE_MEMBERPTR)))
- result = value_cast (dest_type, arg);
- else
- error (_("Invalid reinterpret_cast"));
- if (is_ref)
- result = value_cast (type, value_ref (value_ind (result),
- type->code ()));
- return result;
- }
- /* A helper for value_dynamic_cast. This implements the first of two
- runtime checks: we iterate over all the base classes of the value's
- class which are equal to the desired class; if only one of these
- holds the value, then it is the answer. */
- static int
- dynamic_cast_check_1 (struct type *desired_type,
- const gdb_byte *valaddr,
- LONGEST embedded_offset,
- CORE_ADDR address,
- struct value *val,
- struct type *search_type,
- CORE_ADDR arg_addr,
- struct type *arg_type,
- struct value **result)
- {
- int i, result_count = 0;
- for (i = 0; i < TYPE_N_BASECLASSES (search_type) && result_count < 2; ++i)
- {
- LONGEST offset = baseclass_offset (search_type, i, valaddr,
- embedded_offset,
- address, val);
- if (class_types_same_p (desired_type, TYPE_BASECLASS (search_type, i)))
- {
- if (address + embedded_offset + offset >= arg_addr
- && address + embedded_offset + offset < arg_addr + TYPE_LENGTH (arg_type))
- {
- ++result_count;
- if (!*result)
- *result = value_at_lazy (TYPE_BASECLASS (search_type, i),
- address + embedded_offset + offset);
- }
- }
- else
- result_count += dynamic_cast_check_1 (desired_type,
- valaddr,
- embedded_offset + offset,
- address, val,
- TYPE_BASECLASS (search_type, i),
- arg_addr,
- arg_type,
- result);
- }
- return result_count;
- }
- /* A helper for value_dynamic_cast. This implements the second of two
- runtime checks: we look for a unique public sibling class of the
- argument's declared class. */
- static int
- dynamic_cast_check_2 (struct type *desired_type,
- const gdb_byte *valaddr,
- LONGEST embedded_offset,
- CORE_ADDR address,
- struct value *val,
- struct type *search_type,
- struct value **result)
- {
- int i, result_count = 0;
- for (i = 0; i < TYPE_N_BASECLASSES (search_type) && result_count < 2; ++i)
- {
- LONGEST offset;
- if (! BASETYPE_VIA_PUBLIC (search_type, i))
- continue;
- offset = baseclass_offset (search_type, i, valaddr, embedded_offset,
- address, val);
- if (class_types_same_p (desired_type, TYPE_BASECLASS (search_type, i)))
- {
- ++result_count;
- if (*result == NULL)
- *result = value_at_lazy (TYPE_BASECLASS (search_type, i),
- address + embedded_offset + offset);
- }
- else
- result_count += dynamic_cast_check_2 (desired_type,
- valaddr,
- embedded_offset + offset,
- address, val,
- TYPE_BASECLASS (search_type, i),
- result);
- }
- return result_count;
- }
- /* The C++ dynamic_cast operator. */
- struct value *
- value_dynamic_cast (struct type *type, struct value *arg)
- {
- int full, using_enc;
- LONGEST top;
- struct type *resolved_type = check_typedef (type);
- struct type *arg_type = check_typedef (value_type (arg));
- struct type *class_type, *rtti_type;
- struct value *result, *tem, *original_arg = arg;
- CORE_ADDR addr;
- int is_ref = TYPE_IS_REFERENCE (resolved_type);
- if (resolved_type->code () != TYPE_CODE_PTR
- && !TYPE_IS_REFERENCE (resolved_type))
- error (_("Argument to dynamic_cast must be a pointer or reference type"));
- if (TYPE_TARGET_TYPE (resolved_type)->code () != TYPE_CODE_VOID
- && TYPE_TARGET_TYPE (resolved_type)->code () != TYPE_CODE_STRUCT)
- error (_("Argument to dynamic_cast must be pointer to class or `void *'"));
- class_type = check_typedef (TYPE_TARGET_TYPE (resolved_type));
- if (resolved_type->code () == TYPE_CODE_PTR)
- {
- if (arg_type->code () != TYPE_CODE_PTR
- && ! (arg_type->code () == TYPE_CODE_INT
- && value_as_long (arg) == 0))
- error (_("Argument to dynamic_cast does not have pointer type"));
- if (arg_type->code () == TYPE_CODE_PTR)
- {
- arg_type = check_typedef (TYPE_TARGET_TYPE (arg_type));
- if (arg_type->code () != TYPE_CODE_STRUCT)
- error (_("Argument to dynamic_cast does "
- "not have pointer to class type"));
- }
- /* Handle NULL pointers. */
- if (value_as_long (arg) == 0)
- return value_zero (type, not_lval);
- arg = value_ind (arg);
- }
- else
- {
- if (arg_type->code () != TYPE_CODE_STRUCT)
- error (_("Argument to dynamic_cast does not have class type"));
- }
- /* If the classes are the same, just return the argument. */
- if (class_types_same_p (class_type, arg_type))
- return value_cast (type, arg);
- /* If the target type is a unique base class of the argument's
- declared type, just cast it. */
- if (is_ancestor (class_type, arg_type))
- {
- if (is_unique_ancestor (class_type, arg))
- return value_cast (type, original_arg);
- error (_("Ambiguous dynamic_cast"));
- }
- rtti_type = value_rtti_type (arg, &full, &top, &using_enc);
- if (! rtti_type)
- error (_("Couldn't determine value's most derived type for dynamic_cast"));
- /* Compute the most derived object's address. */
- addr = value_address (arg);
- if (full)
- {
- /* Done. */
- }
- else if (using_enc)
- addr += top;
- else
- addr += top + value_embedded_offset (arg);
- /* dynamic_cast<void *> means to return a pointer to the
- most-derived object. */
- if (resolved_type->code () == TYPE_CODE_PTR
- && TYPE_TARGET_TYPE (resolved_type)->code () == TYPE_CODE_VOID)
- return value_at_lazy (type, addr);
- tem = value_at (type, addr);
- type = value_type (tem);
- /* The first dynamic check specified in 5.2.7. */
- if (is_public_ancestor (arg_type, TYPE_TARGET_TYPE (resolved_type)))
- {
- if (class_types_same_p (rtti_type, TYPE_TARGET_TYPE (resolved_type)))
- return tem;
- result = NULL;
- if (dynamic_cast_check_1 (TYPE_TARGET_TYPE (resolved_type),
- value_contents_for_printing (tem).data (),
- value_embedded_offset (tem),
- value_address (tem), tem,
- rtti_type, addr,
- arg_type,
- &result) == 1)
- return value_cast (type,
- is_ref
- ? value_ref (result, resolved_type->code ())
- : value_addr (result));
- }
- /* The second dynamic check specified in 5.2.7. */
- result = NULL;
- if (is_public_ancestor (arg_type, rtti_type)
- && dynamic_cast_check_2 (TYPE_TARGET_TYPE (resolved_type),
- value_contents_for_printing (tem).data (),
- value_embedded_offset (tem),
- value_address (tem), tem,
- rtti_type, &result) == 1)
- return value_cast (type,
- is_ref
- ? value_ref (result, resolved_type->code ())
- : value_addr (result));
- if (resolved_type->code () == TYPE_CODE_PTR)
- return value_zero (type, not_lval);
- error (_("dynamic_cast failed"));
- }
- /* Create a not_lval value of numeric type TYPE that is one, and return it. */
- struct value *
- value_one (struct type *type)
- {
- struct type *type1 = check_typedef (type);
- struct value *val;
- if (is_integral_type (type1) || is_floating_type (type1))
- {
- val = value_from_longest (type, (LONGEST) 1);
- }
- else if (type1->code () == TYPE_CODE_ARRAY && type1->is_vector ())
- {
- struct type *eltype = check_typedef (TYPE_TARGET_TYPE (type1));
- int i;
- LONGEST low_bound, high_bound;
- if (!get_array_bounds (type1, &low_bound, &high_bound))
- error (_("Could not determine the vector bounds"));
- val = allocate_value (type);
- gdb::array_view<gdb_byte> val_contents = value_contents_writeable (val);
- int elt_len = TYPE_LENGTH (eltype);
- for (i = 0; i < high_bound - low_bound + 1; i++)
- {
- value *tmp = value_one (eltype);
- copy (value_contents_all (tmp),
- val_contents.slice (i * elt_len, elt_len));
- }
- }
- else
- {
- error (_("Not a numeric type."));
- }
- /* value_one result is never used for assignments to. */
- gdb_assert (VALUE_LVAL (val) == not_lval);
- return val;
- }
- /* Helper function for value_at, value_at_lazy, and value_at_lazy_stack.
- The type of the created value may differ from the passed type TYPE.
- Make sure to retrieve the returned values's new type after this call
- e.g. in case the type is a variable length array. */
- static struct value *
- get_value_at (struct type *type, CORE_ADDR addr, int lazy)
- {
- struct value *val;
- if (check_typedef (type)->code () == TYPE_CODE_VOID)
- error (_("Attempt to dereference a generic pointer."));
- val = value_from_contents_and_address (type, NULL, addr);
- if (!lazy)
- value_fetch_lazy (val);
- return val;
- }
- /* Return a value with type TYPE located at ADDR.
- Call value_at only if the data needs to be fetched immediately;
- if we can be 'lazy' and defer the fetch, perhaps indefinitely, call
- value_at_lazy instead. value_at_lazy simply records the address of
- the data and sets the lazy-evaluation-required flag. The lazy flag
- is tested in the value_contents macro, which is used if and when
- the contents are actually required. The type of the created value
- may differ from the passed type TYPE. Make sure to retrieve the
- returned values's new type after this call e.g. in case the type
- is a variable length array.
- Note: value_at does *NOT* handle embedded offsets; perform such
- adjustments before or after calling it. */
- struct value *
- value_at (struct type *type, CORE_ADDR addr)
- {
- return get_value_at (type, addr, 0);
- }
- /* Return a lazy value with type TYPE located at ADDR (cf. value_at).
- The type of the created value may differ from the passed type TYPE.
- Make sure to retrieve the returned values's new type after this call
- e.g. in case the type is a variable length array. */
- struct value *
- value_at_lazy (struct type *type, CORE_ADDR addr)
- {
- return get_value_at (type, addr, 1);
- }
- void
- read_value_memory (struct value *val, LONGEST bit_offset,
- int stack, CORE_ADDR memaddr,
- gdb_byte *buffer, size_t length)
- {
- ULONGEST xfered_total = 0;
- struct gdbarch *arch = get_value_arch (val);
- int unit_size = gdbarch_addressable_memory_unit_size (arch);
- enum target_object object;
- object = stack ? TARGET_OBJECT_STACK_MEMORY : TARGET_OBJECT_MEMORY;
- while (xfered_total < length)
- {
- enum target_xfer_status status;
- ULONGEST xfered_partial;
- status = target_xfer_partial (current_inferior ()->top_target (),
- object, NULL,
- buffer + xfered_total * unit_size, NULL,
- memaddr + xfered_total,
- length - xfered_total,
- &xfered_partial);
- if (status == TARGET_XFER_OK)
- /* nothing */;
- else if (status == TARGET_XFER_UNAVAILABLE)
- mark_value_bits_unavailable (val, (xfered_total * HOST_CHAR_BIT
- + bit_offset),
- xfered_partial * HOST_CHAR_BIT);
- else if (status == TARGET_XFER_EOF)
- memory_error (TARGET_XFER_E_IO, memaddr + xfered_total);
- else
- memory_error (status, memaddr + xfered_total);
- xfered_total += xfered_partial;
- QUIT;
- }
- }
- /* Store the contents of FROMVAL into the location of TOVAL.
- Return a new value with the location of TOVAL and contents of FROMVAL. */
- struct value *
- value_assign (struct value *toval, struct value *fromval)
- {
- struct type *type;
- struct value *val;
- struct frame_id old_frame;
- if (!deprecated_value_modifiable (toval))
- error (_("Left operand of assignment is not a modifiable lvalue."));
- toval = coerce_ref (toval);
- type = value_type (toval);
- if (VALUE_LVAL (toval) != lval_internalvar)
- fromval = value_cast (type, fromval);
- else
- {
- /* Coerce arrays and functions to pointers, except for arrays
- which only live in GDB's storage. */
- if (!value_must_coerce_to_target (fromval))
- fromval = coerce_array (fromval);
- }
- type = check_typedef (type);
- /* Since modifying a register can trash the frame chain, and
- modifying memory can trash the frame cache, we save the old frame
- and then restore the new frame afterwards. */
- old_frame = get_frame_id (deprecated_safe_get_selected_frame ());
- switch (VALUE_LVAL (toval))
- {
- case lval_internalvar:
- set_internalvar (VALUE_INTERNALVAR (toval), fromval);
- return value_of_internalvar (type->arch (),
- VALUE_INTERNALVAR (toval));
- case lval_internalvar_component:
- {
- LONGEST offset = value_offset (toval);
- /* Are we dealing with a bitfield?
- It is important to mention that `value_parent (toval)' is
- non-NULL iff `value_bitsize (toval)' is non-zero. */
- if (value_bitsize (toval))
- {
- /* VALUE_INTERNALVAR below refers to the parent value, while
- the offset is relative to this parent value. */
- gdb_assert (value_parent (value_parent (toval)) == NULL);
- offset += value_offset (value_parent (toval));
- }
- set_internalvar_component (VALUE_INTERNALVAR (toval),
- offset,
- value_bitpos (toval),
- value_bitsize (toval),
- fromval);
- }
- break;
- case lval_memory:
- {
- const gdb_byte *dest_buffer;
- CORE_ADDR changed_addr;
- int changed_len;
- gdb_byte buffer[sizeof (LONGEST)];
- if (value_bitsize (toval))
- {
- struct value *parent = value_parent (toval);
- changed_addr = value_address (parent) + value_offset (toval);
- changed_len = (value_bitpos (toval)
- + value_bitsize (toval)
- + HOST_CHAR_BIT - 1)
- / HOST_CHAR_BIT;
- /* If we can read-modify-write exactly the size of the
- containing type (e.g. short or int) then do so. This
- is safer for volatile bitfields mapped to hardware
- registers. */
- if (changed_len < TYPE_LENGTH (type)
- && TYPE_LENGTH (type) <= (int) sizeof (LONGEST)
- && ((LONGEST) changed_addr % TYPE_LENGTH (type)) == 0)
- changed_len = TYPE_LENGTH (type);
- if (changed_len > (int) sizeof (LONGEST))
- error (_("Can't handle bitfields which "
- "don't fit in a %d bit word."),
- (int) sizeof (LONGEST) * HOST_CHAR_BIT);
- read_memory (changed_addr, buffer, changed_len);
- modify_field (type, buffer, value_as_long (fromval),
- value_bitpos (toval), value_bitsize (toval));
- dest_buffer = buffer;
- }
- else
- {
- changed_addr = value_address (toval);
- changed_len = type_length_units (type);
- dest_buffer = value_contents (fromval).data ();
- }
- write_memory_with_notification (changed_addr, dest_buffer, changed_len);
- }
- break;
- case lval_register:
- {
- struct frame_info *frame;
- struct gdbarch *gdbarch;
- int value_reg;
- /* Figure out which frame this register value is in. The value
- holds the frame_id for the next frame, that is the frame this
- register value was unwound from.
- Below we will call put_frame_register_bytes which requires that
- we pass it the actual frame in which the register value is
- valid, i.e. not the next frame. */
- frame = frame_find_by_id (VALUE_NEXT_FRAME_ID (toval));
- frame = get_prev_frame_always (frame);
- value_reg = VALUE_REGNUM (toval);
- if (!frame)
- error (_("Value being assigned to is no longer active."));
- gdbarch = get_frame_arch (frame);
- if (value_bitsize (toval))
- {
- struct value *parent = value_parent (toval);
- LONGEST offset = value_offset (parent) + value_offset (toval);
- size_t changed_len;
- gdb_byte buffer[sizeof (LONGEST)];
- int optim, unavail;
- changed_len = (value_bitpos (toval)
- + value_bitsize (toval)
- + HOST_CHAR_BIT - 1)
- / HOST_CHAR_BIT;
- if (changed_len > sizeof (LONGEST))
- error (_("Can't handle bitfields which "
- "don't fit in a %d bit word."),
- (int) sizeof (LONGEST) * HOST_CHAR_BIT);
- if (!get_frame_register_bytes (frame, value_reg, offset,
- {buffer, changed_len},
- &optim, &unavail))
- {
- if (optim)
- throw_error (OPTIMIZED_OUT_ERROR,
- _("value has been optimized out"));
- if (unavail)
- throw_error (NOT_AVAILABLE_ERROR,
- _("value is not available"));
- }
- modify_field (type, buffer, value_as_long (fromval),
- value_bitpos (toval), value_bitsize (toval));
- put_frame_register_bytes (frame, value_reg, offset,
- {buffer, changed_len});
- }
- else
- {
- if (gdbarch_convert_register_p (gdbarch, VALUE_REGNUM (toval),
- type))
- {
- /* If TOVAL is a special machine register requiring
- conversion of program values to a special raw
- format. */
- gdbarch_value_to_register (gdbarch, frame,
- VALUE_REGNUM (toval), type,
- value_contents (fromval).data ());
- }
- else
- put_frame_register_bytes (frame, value_reg,
- value_offset (toval),
- value_contents (fromval));
- }
- gdb::observers::register_changed.notify (frame, value_reg);
- break;
- }
- case lval_computed:
- {
- const struct lval_funcs *funcs = value_computed_funcs (toval);
- if (funcs->write != NULL)
- {
- funcs->write (toval, fromval);
- break;
- }
- }
- /* Fall through. */
- default:
- error (_("Left operand of assignment is not an lvalue."));
- }
- /* Assigning to the stack pointer, frame pointer, and other
- (architecture and calling convention specific) registers may
- cause the frame cache and regcache to be out of date. Assigning to memory
- also can. We just do this on all assignments to registers or
- memory, for simplicity's sake; I doubt the slowdown matters. */
- switch (VALUE_LVAL (toval))
- {
- case lval_memory:
- case lval_register:
- case lval_computed:
- gdb::observers::target_changed.notify
- (current_inferior ()->top_target ());
- /* Having destroyed the frame cache, restore the selected
- frame. */
- /* FIXME: cagney/2002-11-02: There has to be a better way of
- doing this. Instead of constantly saving/restoring the
- frame. Why not create a get_selected_frame() function that,
- having saved the selected frame's ID can automatically
- re-find the previously selected frame automatically. */
- {
- struct frame_info *fi = frame_find_by_id (old_frame);
- if (fi != NULL)
- select_frame (fi);
- }
- break;
- default:
- break;
- }
-
- /* If the field does not entirely fill a LONGEST, then zero the sign
- bits. If the field is signed, and is negative, then sign
- extend. */
- if ((value_bitsize (toval) > 0)
- && (value_bitsize (toval) < 8 * (int) sizeof (LONGEST)))
- {
- LONGEST fieldval = value_as_long (fromval);
- LONGEST valmask = (((ULONGEST) 1) << value_bitsize (toval)) - 1;
- fieldval &= valmask;
- if (!type->is_unsigned ()
- && (fieldval & (valmask ^ (valmask >> 1))))
- fieldval |= ~valmask;
- fromval = value_from_longest (type, fieldval);
- }
- /* The return value is a copy of TOVAL so it shares its location
- information, but its contents are updated from FROMVAL. This
- implies the returned value is not lazy, even if TOVAL was. */
- val = value_copy (toval);
- set_value_lazy (val, 0);
- copy (value_contents (fromval), value_contents_raw (val));
- /* We copy over the enclosing type and pointed-to offset from FROMVAL
- in the case of pointer types. For object types, the enclosing type
- and embedded offset must *not* be copied: the target object refered
- to by TOVAL retains its original dynamic type after assignment. */
- if (type->code () == TYPE_CODE_PTR)
- {
- set_value_enclosing_type (val, value_enclosing_type (fromval));
- set_value_pointed_to_offset (val, value_pointed_to_offset (fromval));
- }
- return val;
- }
- /* Extend a value ARG1 to COUNT repetitions of its type. */
- struct value *
- value_repeat (struct value *arg1, int count)
- {
- struct value *val;
- if (VALUE_LVAL (arg1) != lval_memory)
- error (_("Only values in memory can be extended with '@'."));
- if (count < 1)
- error (_("Invalid number %d of repetitions."), count);
- val = allocate_repeat_value (value_enclosing_type (arg1), count);
- VALUE_LVAL (val) = lval_memory;
- set_value_address (val, value_address (arg1));
- read_value_memory (val, 0, value_stack (val), value_address (val),
- value_contents_all_raw (val).data (),
- type_length_units (value_enclosing_type (val)));
- return val;
- }
- struct value *
- value_of_variable (struct symbol *var, const struct block *b)
- {
- struct frame_info *frame = NULL;
- if (symbol_read_needs_frame (var))
- frame = get_selected_frame (_("No frame selected."));
- return read_var_value (var, b, frame);
- }
- struct value *
- address_of_variable (struct symbol *var, const struct block *b)
- {
- struct type *type = var->type ();
- struct value *val;
- /* Evaluate it first; if the result is a memory address, we're fine.
- Lazy evaluation pays off here. */
- val = value_of_variable (var, b);
- type = value_type (val);
- if ((VALUE_LVAL (val) == lval_memory && value_lazy (val))
- || type->code () == TYPE_CODE_FUNC)
- {
- CORE_ADDR addr = value_address (val);
- return value_from_pointer (lookup_pointer_type (type), addr);
- }
- /* Not a memory address; check what the problem was. */
- switch (VALUE_LVAL (val))
- {
- case lval_register:
- {
- struct frame_info *frame;
- const char *regname;
- frame = frame_find_by_id (VALUE_NEXT_FRAME_ID (val));
- gdb_assert (frame);
- regname = gdbarch_register_name (get_frame_arch (frame),
- VALUE_REGNUM (val));
- gdb_assert (regname && *regname);
- error (_("Address requested for identifier "
- "\"%s\" which is in register $%s"),
- var->print_name (), regname);
- break;
- }
- default:
- error (_("Can't take address of \"%s\" which isn't an lvalue."),
- var->print_name ());
- break;
- }
- return val;
- }
- /* See value.h. */
- bool
- value_must_coerce_to_target (struct value *val)
- {
- struct type *valtype;
- /* The only lval kinds which do not live in target memory. */
- if (VALUE_LVAL (val) != not_lval
- && VALUE_LVAL (val) != lval_internalvar
- && VALUE_LVAL (val) != lval_xcallable)
- return false;
- valtype = check_typedef (value_type (val));
- switch (valtype->code ())
- {
- case TYPE_CODE_ARRAY:
- return valtype->is_vector () ? 0 : 1;
- case TYPE_CODE_STRING:
- return true;
- default:
- return false;
- }
- }
- /* Make sure that VAL lives in target memory if it's supposed to. For
- instance, strings are constructed as character arrays in GDB's
- storage, and this function copies them to the target. */
- struct value *
- value_coerce_to_target (struct value *val)
- {
- LONGEST length;
- CORE_ADDR addr;
- if (!value_must_coerce_to_target (val))
- return val;
- length = TYPE_LENGTH (check_typedef (value_type (val)));
- addr = allocate_space_in_inferior (length);
- write_memory (addr, value_contents (val).data (), length);
- return value_at_lazy (value_type (val), addr);
- }
- /* Given a value which is an array, return a value which is a pointer
- to its first element, regardless of whether or not the array has a
- nonzero lower bound.
- FIXME: A previous comment here indicated that this routine should
- be substracting the array's lower bound. It's not clear to me that
- this is correct. Given an array subscripting operation, it would
- certainly work to do the adjustment here, essentially computing:
- (&array[0] - (lowerbound * sizeof array[0])) + (index * sizeof array[0])
- However I believe a more appropriate and logical place to account
- for the lower bound is to do so in value_subscript, essentially
- computing:
- (&array[0] + ((index - lowerbound) * sizeof array[0]))
- As further evidence consider what would happen with operations
- other than array subscripting, where the caller would get back a
- value that had an address somewhere before the actual first element
- of the array, and the information about the lower bound would be
- lost because of the coercion to pointer type. */
- struct value *
- value_coerce_array (struct value *arg1)
- {
- struct type *type = check_typedef (value_type (arg1));
- /* If the user tries to do something requiring a pointer with an
- array that has not yet been pushed to the target, then this would
- be a good time to do so. */
- arg1 = value_coerce_to_target (arg1);
- if (VALUE_LVAL (arg1) != lval_memory)
- error (_("Attempt to take address of value not located in memory."));
- return value_from_pointer (lookup_pointer_type (TYPE_TARGET_TYPE (type)),
- value_address (arg1));
- }
- /* Given a value which is a function, return a value which is a pointer
- to it. */
- struct value *
- value_coerce_function (struct value *arg1)
- {
- struct value *retval;
- if (VALUE_LVAL (arg1) != lval_memory)
- error (_("Attempt to take address of value not located in memory."));
- retval = value_from_pointer (lookup_pointer_type (value_type (arg1)),
- value_address (arg1));
- return retval;
- }
- /* Return a pointer value for the object for which ARG1 is the
- contents. */
- struct value *
- value_addr (struct value *arg1)
- {
- struct value *arg2;
- struct type *type = check_typedef (value_type (arg1));
- if (TYPE_IS_REFERENCE (type))
- {
- if (value_bits_synthetic_pointer (arg1, value_embedded_offset (arg1),
- TARGET_CHAR_BIT * TYPE_LENGTH (type)))
- arg1 = coerce_ref (arg1);
- else
- {
- /* Copy the value, but change the type from (T&) to (T*). We
- keep the same location information, which is efficient, and
- allows &(&X) to get the location containing the reference.
- Do the same to its enclosing type for consistency. */
- struct type *type_ptr
- = lookup_pointer_type (TYPE_TARGET_TYPE (type));
- struct type *enclosing_type
- = check_typedef (value_enclosing_type (arg1));
- struct type *enclosing_type_ptr
- = lookup_pointer_type (TYPE_TARGET_TYPE (enclosing_type));
- arg2 = value_copy (arg1);
- deprecated_set_value_type (arg2, type_ptr);
- set_value_enclosing_type (arg2, enclosing_type_ptr);
- return arg2;
- }
- }
- if (type->code () == TYPE_CODE_FUNC)
- return value_coerce_function (arg1);
- /* If this is an array that has not yet been pushed to the target,
- then this would be a good time to force it to memory. */
- arg1 = value_coerce_to_target (arg1);
- if (VALUE_LVAL (arg1) != lval_memory)
- error (_("Attempt to take address of value not located in memory."));
- /* Get target memory address. */
- arg2 = value_from_pointer (lookup_pointer_type (value_type (arg1)),
- (value_address (arg1)
- + value_embedded_offset (arg1)));
- /* This may be a pointer to a base subobject; so remember the
- full derived object's type ... */
- set_value_enclosing_type (arg2,
- lookup_pointer_type (value_enclosing_type (arg1)));
- /* ... and also the relative position of the subobject in the full
- object. */
- set_value_pointed_to_offset (arg2, value_embedded_offset (arg1));
- return arg2;
- }
- /* Return a reference value for the object for which ARG1 is the
- contents. */
- struct value *
- value_ref (struct value *arg1, enum type_code refcode)
- {
- struct value *arg2;
- struct type *type = check_typedef (value_type (arg1));
- gdb_assert (refcode == TYPE_CODE_REF || refcode == TYPE_CODE_RVALUE_REF);
- if ((type->code () == TYPE_CODE_REF
- || type->code () == TYPE_CODE_RVALUE_REF)
- && type->code () == refcode)
- return arg1;
- arg2 = value_addr (arg1);
- deprecated_set_value_type (arg2, lookup_reference_type (type, refcode));
- return arg2;
- }
- /* Given a value of a pointer type, apply the C unary * operator to
- it. */
- struct value *
- value_ind (struct value *arg1)
- {
- struct type *base_type;
- struct value *arg2;
- arg1 = coerce_array (arg1);
- base_type = check_typedef (value_type (arg1));
- if (VALUE_LVAL (arg1) == lval_computed)
- {
- const struct lval_funcs *funcs = value_computed_funcs (arg1);
- if (funcs->indirect)
- {
- struct value *result = funcs->indirect (arg1);
- if (result)
- return result;
- }
- }
- if (base_type->code () == TYPE_CODE_PTR)
- {
- struct type *enc_type;
- /* We may be pointing to something embedded in a larger object.
- Get the real type of the enclosing object. */
- enc_type = check_typedef (value_enclosing_type (arg1));
- enc_type = TYPE_TARGET_TYPE (enc_type);
- CORE_ADDR base_addr;
- if (check_typedef (enc_type)->code () == TYPE_CODE_FUNC
- || check_typedef (enc_type)->code () == TYPE_CODE_METHOD)
- {
- /* For functions, go through find_function_addr, which knows
- how to handle function descriptors. */
- base_addr = find_function_addr (arg1, NULL);
- }
- else
- {
- /* Retrieve the enclosing object pointed to. */
- base_addr = (value_as_address (arg1)
- - value_pointed_to_offset (arg1));
- }
- arg2 = value_at_lazy (enc_type, base_addr);
- enc_type = value_type (arg2);
- return readjust_indirect_value_type (arg2, enc_type, base_type,
- arg1, base_addr);
- }
- error (_("Attempt to take contents of a non-pointer value."));
- }
- /* Create a value for an array by allocating space in GDB, copying the
- data into that space, and then setting up an array value.
- The array bounds are set from LOWBOUND and HIGHBOUND, and the array
- is populated from the values passed in ELEMVEC.
- The element type of the array is inherited from the type of the
- first element, and all elements must have the same size (though we
- don't currently enforce any restriction on their types). */
- struct value *
- value_array (int lowbound, int highbound, struct value **elemvec)
- {
- int nelem;
- int idx;
- ULONGEST typelength;
- struct value *val;
- struct type *arraytype;
- /* Validate that the bounds are reasonable and that each of the
- elements have the same size. */
- nelem = highbound - lowbound + 1;
- if (nelem <= 0)
- {
- error (_("bad array bounds (%d, %d)"), lowbound, highbound);
- }
- typelength = type_length_units (value_enclosing_type (elemvec[0]));
- for (idx = 1; idx < nelem; idx++)
- {
- if (type_length_units (value_enclosing_type (elemvec[idx]))
- != typelength)
- {
- error (_("array elements must all be the same size"));
- }
- }
- arraytype = lookup_array_range_type (value_enclosing_type (elemvec[0]),
- lowbound, highbound);
- if (!current_language->c_style_arrays_p ())
- {
- val = allocate_value (arraytype);
- for (idx = 0; idx < nelem; idx++)
- value_contents_copy (val, idx * typelength, elemvec[idx], 0,
- typelength);
- return val;
- }
- /* Allocate space to store the array, and then initialize it by
- copying in each element. */
- val = allocate_value (arraytype);
- for (idx = 0; idx < nelem; idx++)
- value_contents_copy (val, idx * typelength, elemvec[idx], 0, typelength);
- return val;
- }
- struct value *
- value_cstring (const char *ptr, ssize_t len, struct type *char_type)
- {
- struct value *val;
- int lowbound = current_language->string_lower_bound ();
- ssize_t highbound = len / TYPE_LENGTH (char_type);
- struct type *stringtype
- = lookup_array_range_type (char_type, lowbound, highbound + lowbound - 1);
- val = allocate_value (stringtype);
- memcpy (value_contents_raw (val).data (), ptr, len);
- return val;
- }
- /* Create a value for a string constant by allocating space in the
- inferior, copying the data into that space, and returning the
- address with type TYPE_CODE_STRING. PTR points to the string
- constant data; LEN is number of characters.
- Note that string types are like array of char types with a lower
- bound of zero and an upper bound of LEN - 1. Also note that the
- string may contain embedded null bytes. */
- struct value *
- value_string (const char *ptr, ssize_t len, struct type *char_type)
- {
- struct value *val;
- int lowbound = current_language->string_lower_bound ();
- ssize_t highbound = len / TYPE_LENGTH (char_type);
- struct type *stringtype
- = lookup_string_range_type (char_type, lowbound, highbound + lowbound - 1);
- val = allocate_value (stringtype);
- memcpy (value_contents_raw (val).data (), ptr, len);
- return val;
- }
- /* See if we can pass arguments in T2 to a function which takes arguments
- of types T1. T1 is a list of NARGS arguments, and T2 is an array_view
- of the values we're trying to pass. If some arguments need coercion of
- some sort, then the coerced values are written into T2. Return value is
- 0 if the arguments could be matched, or the position at which they
- differ if not.
- STATICP is nonzero if the T1 argument list came from a static
- member function. T2 must still include the ``this'' pointer, but
- it will be skipped.
- For non-static member functions, we ignore the first argument,
- which is the type of the instance variable. This is because we
- want to handle calls with objects from derived classes. This is
- not entirely correct: we should actually check to make sure that a
- requested operation is type secure, shouldn't we? FIXME. */
- static int
- typecmp (bool staticp, bool varargs, int nargs,
- struct field t1[], gdb::array_view<value *> t2)
- {
- int i;
- /* Skip ``this'' argument if applicable. T2 will always include
- THIS. */
- if (staticp)
- t2 = t2.slice (1);
- for (i = 0;
- (i < nargs) && t1[i].type ()->code () != TYPE_CODE_VOID;
- i++)
- {
- struct type *tt1, *tt2;
- if (i == t2.size ())
- return i + 1;
- tt1 = check_typedef (t1[i].type ());
- tt2 = check_typedef (value_type (t2[i]));
- if (TYPE_IS_REFERENCE (tt1)
- /* We should be doing hairy argument matching, as below. */
- && (check_typedef (TYPE_TARGET_TYPE (tt1))->code ()
- == tt2->code ()))
- {
- if (tt2->code () == TYPE_CODE_ARRAY)
- t2[i] = value_coerce_array (t2[i]);
- else
- t2[i] = value_ref (t2[i], tt1->code ());
- continue;
- }
- /* djb - 20000715 - Until the new type structure is in the
- place, and we can attempt things like implicit conversions,
- we need to do this so you can take something like a map<const
- char *>, and properly access map["hello"], because the
- argument to [] will be a reference to a pointer to a char,
- and the argument will be a pointer to a char. */
- while (TYPE_IS_REFERENCE (tt1) || tt1->code () == TYPE_CODE_PTR)
- {
- tt1 = check_typedef ( TYPE_TARGET_TYPE (tt1) );
- }
- while (tt2->code () == TYPE_CODE_ARRAY
- || tt2->code () == TYPE_CODE_PTR
- || TYPE_IS_REFERENCE (tt2))
- {
- tt2 = check_typedef (TYPE_TARGET_TYPE (tt2));
- }
- if (tt1->code () == tt2->code ())
- continue;
- /* Array to pointer is a `trivial conversion' according to the
- ARM. */
- /* We should be doing much hairier argument matching (see
- section 13.2 of the ARM), but as a quick kludge, just check
- for the same type code. */
- if (t1[i].type ()->code () != value_type (t2[i])->code ())
- return i + 1;
- }
- if (varargs || i == t2.size ())
- return 0;
- return i + 1;
- }
- /* Helper class for search_struct_field that keeps track of found
- results and possibly throws an exception if the search yields
- ambiguous results. See search_struct_field for description of
- LOOKING_FOR_BASECLASS. */
- struct struct_field_searcher
- {
- /* A found field. */
- struct found_field
- {
- /* Path to the structure where the field was found. */
- std::vector<struct type *> path;
- /* The field found. */
- struct value *field_value;
- };
- /* See corresponding fields for description of parameters. */
- struct_field_searcher (const char *name,
- struct type *outermost_type,
- bool looking_for_baseclass)
- : m_name (name),
- m_looking_for_baseclass (looking_for_baseclass),
- m_outermost_type (outermost_type)
- {
- }
- /* The search entry point. If LOOKING_FOR_BASECLASS is true and the
- base class search yields ambiguous results, this throws an
- exception. If LOOKING_FOR_BASECLASS is false, the found fields
- are accumulated and the caller (search_struct_field) takes care
- of throwing an error if the field search yields ambiguous
- results. The latter is done that way so that the error message
- can include a list of all the found candidates. */
- void search (struct value *arg, LONGEST offset, struct type *type);
- const std::vector<found_field> &fields ()
- {
- return m_fields;
- }
- struct value *baseclass ()
- {
- return m_baseclass;
- }
- private:
- /* Update results to include V, a found field/baseclass. */
- void update_result (struct value *v, LONGEST boffset);
- /* The name of the field/baseclass we're searching for. */
- const char *m_name;
- /* Whether we're looking for a baseclass, or a field. */
- const bool m_looking_for_baseclass;
- /* The offset of the baseclass containing the field/baseclass we
- last recorded. */
- LONGEST m_last_boffset = 0;
- /* If looking for a baseclass, then the result is stored here. */
- struct value *m_baseclass = nullptr;
- /* When looking for fields, the found candidates are stored
- here. */
- std::vector<found_field> m_fields;
- /* The type of the initial type passed to search_struct_field; this
- is used for error reporting when the lookup is ambiguous. */
- struct type *m_outermost_type;
- /* The full path to the struct being inspected. E.g. for field 'x'
- defined in class B inherited by class A, we have A and B pushed
- on the path. */
- std::vector <struct type *> m_struct_path;
- };
- void
- struct_field_searcher::update_result (struct value *v, LONGEST boffset)
- {
- if (v != NULL)
- {
- if (m_looking_for_baseclass)
- {
- if (m_baseclass != nullptr
- /* The result is not ambiguous if all the classes that are
- found occupy the same space. */
- && m_last_boffset != boffset)
- error (_("base class '%s' is ambiguous in type '%s'"),
- m_name, TYPE_SAFE_NAME (m_outermost_type));
- m_baseclass = v;
- m_last_boffset = boffset;
- }
- else
- {
- /* The field is not ambiguous if it occupies the same
- space. */
- if (m_fields.empty () || m_last_boffset != boffset)
- m_fields.push_back ({m_struct_path, v});
- else
- {
- /*Fields can occupy the same space and have the same name (be
- ambiguous). This can happen when fields in two different base
- classes are marked [[no_unique_address]] and have the same name.
- The C++ standard says that such fields can only occupy the same
- space if they are of different type, but we don't rely on that in
- the following code. */
- bool ambiguous = false, insert = true;
- for (const found_field &field: m_fields)
- {
- if(field.path.back () != m_struct_path.back ())
- {
- /* Same boffset points to members of different classes.
- We have found an ambiguity and should record it. */
- ambiguous = true;
- }
- else
- {
- /* We don't need to insert this value again, because a
- non-ambiguous path already leads to it. */
- insert = false;
- break;
- }
- }
- if (ambiguous && insert)
- m_fields.push_back ({m_struct_path, v});
- }
- }
- }
- }
- /* A helper for search_struct_field. This does all the work; most
- arguments are as passed to search_struct_field. */
- void
- struct_field_searcher::search (struct value *arg1, LONGEST offset,
- struct type *type)
- {
- int i;
- int nbases;
- m_struct_path.push_back (type);
- SCOPE_EXIT { m_struct_path.pop_back (); };
- type = check_typedef (type);
- nbases = TYPE_N_BASECLASSES (type);
- if (!m_looking_for_baseclass)
- for (i = type->num_fields () - 1; i >= nbases; i--)
- {
- const char *t_field_name = type->field (i).name ();
- if (t_field_name && (strcmp_iw (t_field_name, m_name) == 0))
- {
- struct value *v;
- if (field_is_static (&type->field (i)))
- v = value_static_field (type, i);
- else
- v = value_primitive_field (arg1, offset, i, type);
- update_result (v, offset);
- return;
- }
- if (t_field_name
- && t_field_name[0] == '\0')
- {
- struct type *field_type = type->field (i).type ();
- if (field_type->code () == TYPE_CODE_UNION
- || field_type->code () == TYPE_CODE_STRUCT)
- {
- /* Look for a match through the fields of an anonymous
- union, or anonymous struct. C++ provides anonymous
- unions.
- In the GNU Chill (now deleted from GDB)
- implementation of variant record types, each
- <alternative field> has an (anonymous) union type,
- each member of the union represents a <variant
- alternative>. Each <variant alternative> is
- represented as a struct, with a member for each
- <variant field>. */
- LONGEST new_offset = offset;
- /* This is pretty gross. In G++, the offset in an
- anonymous union is relative to the beginning of the
- enclosing struct. In the GNU Chill (now deleted
- from GDB) implementation of variant records, the
- bitpos is zero in an anonymous union field, so we
- have to add the offset of the union here. */
- if (field_type->code () == TYPE_CODE_STRUCT
- || (field_type->num_fields () > 0
- && field_type->field (0).loc_bitpos () == 0))
- new_offset += type->field (i).loc_bitpos () / 8;
- search (arg1, new_offset, field_type);
- }
- }
- }
- for (i = 0; i < nbases; i++)
- {
- struct value *v = NULL;
- struct type *basetype = check_typedef (TYPE_BASECLASS (type, i));
- /* If we are looking for baseclasses, this is what we get when
- we hit them. But it could happen that the base part's member
- name is not yet filled in. */
- int found_baseclass = (m_looking_for_baseclass
- && TYPE_BASECLASS_NAME (type, i) != NULL
- && (strcmp_iw (m_name,
- TYPE_BASECLASS_NAME (type,
- i)) == 0));
- LONGEST boffset = value_embedded_offset (arg1) + offset;
- if (BASETYPE_VIA_VIRTUAL (type, i))
- {
- struct value *v2;
- boffset = baseclass_offset (type, i,
- value_contents_for_printing (arg1).data (),
- value_embedded_offset (arg1) + offset,
- value_address (arg1),
- arg1);
- /* The virtual base class pointer might have been clobbered
- by the user program. Make sure that it still points to a
- valid memory location. */
- boffset += value_embedded_offset (arg1) + offset;
- if (boffset < 0
- || boffset >= TYPE_LENGTH (value_enclosing_type (arg1)))
- {
- CORE_ADDR base_addr;
- base_addr = value_address (arg1) + boffset;
- v2 = value_at_lazy (basetype, base_addr);
- if (target_read_memory (base_addr,
- value_contents_raw (v2).data (),
- TYPE_LENGTH (value_type (v2))) != 0)
- error (_("virtual baseclass botch"));
- }
- else
- {
- v2 = value_copy (arg1);
- deprecated_set_value_type (v2, basetype);
- set_value_embedded_offset (v2, boffset);
- }
- if (found_baseclass)
- v = v2;
- else
- search (v2, 0, TYPE_BASECLASS (type, i));
- }
- else if (found_baseclass)
- v = value_primitive_field (arg1, offset, i, type);
- else
- {
- search (arg1, offset + TYPE_BASECLASS_BITPOS (type, i) / 8,
- basetype);
- }
- update_result (v, boffset);
- }
- }
- /* Helper function used by value_struct_elt to recurse through
- baseclasses. Look for a field NAME in ARG1. Search in it assuming
- it has (class) type TYPE. If found, return value, else return NULL.
- If LOOKING_FOR_BASECLASS, then instead of looking for struct
- fields, look for a baseclass named NAME. */
- static struct value *
- search_struct_field (const char *name, struct value *arg1,
- struct type *type, int looking_for_baseclass)
- {
- struct_field_searcher searcher (name, type, looking_for_baseclass);
- searcher.search (arg1, 0, type);
- if (!looking_for_baseclass)
- {
- const auto &fields = searcher.fields ();
- if (fields.empty ())
- return nullptr;
- else if (fields.size () == 1)
- return fields[0].field_value;
- else
- {
- std::string candidates;
- for (auto &&candidate : fields)
- {
- gdb_assert (!candidate.path.empty ());
- struct type *field_type = value_type (candidate.field_value);
- struct type *struct_type = candidate.path.back ();
- std::string path;
- bool first = true;
- for (struct type *t : candidate.path)
- {
- if (first)
- first = false;
- else
- path += " -> ";
- path += t->name ();
- }
- candidates += string_printf ("\n '%s %s::%s' (%s)",
- TYPE_SAFE_NAME (field_type),
- TYPE_SAFE_NAME (struct_type),
- name,
- path.c_str ());
- }
- error (_("Request for member '%s' is ambiguous in type '%s'."
- " Candidates are:%s"),
- name, TYPE_SAFE_NAME (type),
- candidates.c_str ());
- }
- }
- else
- return searcher.baseclass ();
- }
- /* Helper function used by value_struct_elt to recurse through
- baseclasses. Look for a field NAME in ARG1. Adjust the address of
- ARG1 by OFFSET bytes, and search in it assuming it has (class) type
- TYPE.
- ARGS is an optional array of argument values used to help finding NAME.
- The contents of ARGS can be adjusted if type coercion is required in
- order to find a matching NAME.
- If found, return value, else if name matched and args not return
- (value) -1, else return NULL. */
- static struct value *
- search_struct_method (const char *name, struct value **arg1p,
- gdb::optional<gdb::array_view<value *>> args,
- LONGEST offset, int *static_memfuncp,
- struct type *type)
- {
- int i;
- struct value *v;
- int name_matched = 0;
- type = check_typedef (type);
- for (i = TYPE_NFN_FIELDS (type) - 1; i >= 0; i--)
- {
- const char *t_field_name = TYPE_FN_FIELDLIST_NAME (type, i);
- if (t_field_name && (strcmp_iw (t_field_name, name) == 0))
- {
- int j = TYPE_FN_FIELDLIST_LENGTH (type, i) - 1;
- struct fn_field *f = TYPE_FN_FIELDLIST1 (type, i);
- name_matched = 1;
- check_stub_method_group (type, i);
- if (j > 0 && !args.has_value ())
- error (_("cannot resolve overloaded method "
- "`%s': no arguments supplied"), name);
- else if (j == 0 && !args.has_value ())
- {
- v = value_fn_field (arg1p, f, j, type, offset);
- if (v != NULL)
- return v;
- }
- else
- while (j >= 0)
- {
- gdb_assert (args.has_value ());
- if (!typecmp (TYPE_FN_FIELD_STATIC_P (f, j),
- TYPE_FN_FIELD_TYPE (f, j)->has_varargs (),
- TYPE_FN_FIELD_TYPE (f, j)->num_fields (),
- TYPE_FN_FIELD_ARGS (f, j), *args))
- {
- if (TYPE_FN_FIELD_VIRTUAL_P (f, j))
- return value_virtual_fn_field (arg1p, f, j,
- type, offset);
- if (TYPE_FN_FIELD_STATIC_P (f, j)
- && static_memfuncp)
- *static_memfuncp = 1;
- v = value_fn_field (arg1p, f, j, type, offset);
- if (v != NULL)
- return v;
- }
- j--;
- }
- }
- }
- for (i = TYPE_N_BASECLASSES (type) - 1; i >= 0; i--)
- {
- LONGEST base_offset;
- LONGEST this_offset;
- if (BASETYPE_VIA_VIRTUAL (type, i))
- {
- struct type *baseclass = check_typedef (TYPE_BASECLASS (type, i));
- struct value *base_val;
- const gdb_byte *base_valaddr;
- /* The virtual base class pointer might have been
- clobbered by the user program. Make sure that it
- still points to a valid memory location. */
- if (offset < 0 || offset >= TYPE_LENGTH (type))
- {
- CORE_ADDR address;
- gdb::byte_vector tmp (TYPE_LENGTH (baseclass));
- address = value_address (*arg1p);
- if (target_read_memory (address + offset,
- tmp.data (), TYPE_LENGTH (baseclass)) != 0)
- error (_("virtual baseclass botch"));
- base_val = value_from_contents_and_address (baseclass,
- tmp.data (),
- address + offset);
- base_valaddr = value_contents_for_printing (base_val).data ();
- this_offset = 0;
- }
- else
- {
- base_val = *arg1p;
- base_valaddr = value_contents_for_printing (*arg1p).data ();
- this_offset = offset;
- }
- base_offset = baseclass_offset (type, i, base_valaddr,
- this_offset, value_address (base_val),
- base_val);
- }
- else
- {
- base_offset = TYPE_BASECLASS_BITPOS (type, i) / 8;
- }
- v = search_struct_method (name, arg1p, args, base_offset + offset,
- static_memfuncp, TYPE_BASECLASS (type, i));
- if (v == (struct value *) - 1)
- {
- name_matched = 1;
- }
- else if (v)
- {
- /* FIXME-bothner: Why is this commented out? Why is it here? */
- /* *arg1p = arg1_tmp; */
- return v;
- }
- }
- if (name_matched)
- return (struct value *) - 1;
- else
- return NULL;
- }
- /* Given *ARGP, a value of type (pointer to a)* structure/union,
- extract the component named NAME from the ultimate target
- structure/union and return it as a value with its appropriate type.
- ERR is used in the error message if *ARGP's type is wrong.
- C++: ARGS is a list of argument types to aid in the selection of
- an appropriate method. Also, handle derived types.
- STATIC_MEMFUNCP, if non-NULL, points to a caller-supplied location
- where the truthvalue of whether the function that was resolved was
- a static member function or not is stored.
- ERR is an error message to be printed in case the field is not
- found. */
- struct value *
- value_struct_elt (struct value **argp,
- gdb::optional<gdb::array_view<value *>> args,
- const char *name, int *static_memfuncp, const char *err)
- {
- struct type *t;
- struct value *v;
- *argp = coerce_array (*argp);
- t = check_typedef (value_type (*argp));
- /* Follow pointers until we get to a non-pointer. */
- while (t->is_pointer_or_reference ())
- {
- *argp = value_ind (*argp);
- /* Don't coerce fn pointer to fn and then back again! */
- if (check_typedef (value_type (*argp))->code () != TYPE_CODE_FUNC)
- *argp = coerce_array (*argp);
- t = check_typedef (value_type (*argp));
- }
- if (t->code () != TYPE_CODE_STRUCT
- && t->code () != TYPE_CODE_UNION)
- error (_("Attempt to extract a component of a value that is not a %s."),
- err);
- /* Assume it's not, unless we see that it is. */
- if (static_memfuncp)
- *static_memfuncp = 0;
- if (!args.has_value ())
- {
- /* if there are no arguments ...do this... */
- /* Try as a field first, because if we succeed, there is less
- work to be done. */
- v = search_struct_field (name, *argp, t, 0);
- if (v)
- return v;
- if (current_language->la_language == language_fortran)
- {
- /* If it is not a field it is the type name of an inherited
- structure. */
- v = search_struct_field (name, *argp, t, 1);
- if (v)
- return v;
- }
- /* C++: If it was not found as a data field, then try to
- return it as a pointer to a method. */
- v = search_struct_method (name, argp, args, 0,
- static_memfuncp, t);
- if (v == (struct value *) - 1)
- error (_("Cannot take address of method %s."), name);
- else if (v == 0)
- {
- if (TYPE_NFN_FIELDS (t))
- error (_("There is no member or method named %s."), name);
- else
- error (_("There is no member named %s."), name);
- }
- return v;
- }
- v = search_struct_method (name, argp, args, 0,
- static_memfuncp, t);
- if (v == (struct value *) - 1)
- {
- error (_("One of the arguments you tried to pass to %s could not "
- "be converted to what the function wants."), name);
- }
- else if (v == 0)
- {
- /* See if user tried to invoke data as function. If so, hand it
- back. If it's not callable (i.e., a pointer to function),
- gdb should give an error. */
- v = search_struct_field (name, *argp, t, 0);
- /* If we found an ordinary field, then it is not a method call.
- So, treat it as if it were a static member function. */
- if (v && static_memfuncp)
- *static_memfuncp = 1;
- }
- if (!v)
- throw_error (NOT_FOUND_ERROR,
- _("Structure has no component named %s."), name);
- return v;
- }
- /* Given *ARGP, a value of type structure or union, or a pointer/reference
- to a structure or union, extract and return its component (field) of
- type FTYPE at the specified BITPOS.
- Throw an exception on error. */
- struct value *
- value_struct_elt_bitpos (struct value **argp, int bitpos, struct type *ftype,
- const char *err)
- {
- struct type *t;
- int i;
- *argp = coerce_array (*argp);
- t = check_typedef (value_type (*argp));
- while (t->is_pointer_or_reference ())
- {
- *argp = value_ind (*argp);
- if (check_typedef (value_type (*argp))->code () != TYPE_CODE_FUNC)
- *argp = coerce_array (*argp);
- t = check_typedef (value_type (*argp));
- }
- if (t->code () != TYPE_CODE_STRUCT
- && t->code () != TYPE_CODE_UNION)
- error (_("Attempt to extract a component of a value that is not a %s."),
- err);
- for (i = TYPE_N_BASECLASSES (t); i < t->num_fields (); i++)
- {
- if (!field_is_static (&t->field (i))
- && bitpos == t->field (i).loc_bitpos ()
- && types_equal (ftype, t->field (i).type ()))
- return value_primitive_field (*argp, 0, i, t);
- }
- error (_("No field with matching bitpos and type."));
- /* Never hit. */
- return NULL;
- }
- /* Search through the methods of an object (and its bases) to find a
- specified method. Return a reference to the fn_field list METHODS of
- overloaded instances defined in the source language. If available
- and matching, a vector of matching xmethods defined in extension
- languages are also returned in XMETHODS.
- Helper function for value_find_oload_list.
- ARGP is a pointer to a pointer to a value (the object).
- METHOD is a string containing the method name.
- OFFSET is the offset within the value.
- TYPE is the assumed type of the object.
- METHODS is a pointer to the matching overloaded instances defined
- in the source language. Since this is a recursive function,
- *METHODS should be set to NULL when calling this function.
- NUM_FNS is the number of overloaded instances. *NUM_FNS should be set to
- 0 when calling this function.
- XMETHODS is the vector of matching xmethod workers. *XMETHODS
- should also be set to NULL when calling this function.
- BASETYPE is set to the actual type of the subobject where the
- method is found.
- BOFFSET is the offset of the base subobject where the method is found. */
- static void
- find_method_list (struct value **argp, const char *method,
- LONGEST offset, struct type *type,
- gdb::array_view<fn_field> *methods,
- std::vector<xmethod_worker_up> *xmethods,
- struct type **basetype, LONGEST *boffset)
- {
- int i;
- struct fn_field *f = NULL;
- gdb_assert (methods != NULL && xmethods != NULL);
- type = check_typedef (type);
- /* First check in object itself.
- This function is called recursively to search through base classes.
- If there is a source method match found at some stage, then we need not
- look for source methods in consequent recursive calls. */
- if (methods->empty ())
- {
- for (i = TYPE_NFN_FIELDS (type) - 1; i >= 0; i--)
- {
- /* pai: FIXME What about operators and type conversions? */
- const char *fn_field_name = TYPE_FN_FIELDLIST_NAME (type, i);
- if (fn_field_name && (strcmp_iw (fn_field_name, method) == 0))
- {
- int len = TYPE_FN_FIELDLIST_LENGTH (type, i);
- f = TYPE_FN_FIELDLIST1 (type, i);
- *methods = gdb::make_array_view (f, len);
- *basetype = type;
- *boffset = offset;
- /* Resolve any stub methods. */
- check_stub_method_group (type, i);
- break;
- }
- }
- }
- /* Unlike source methods, xmethods can be accumulated over successive
- recursive calls. In other words, an xmethod named 'm' in a class
- will not hide an xmethod named 'm' in its base class(es). We want
- it to be this way because xmethods are after all convenience functions
- and hence there is no point restricting them with something like method
- hiding. Moreover, if hiding is done for xmethods as well, then we will
- have to provide a mechanism to un-hide (like the 'using' construct). */
- get_matching_xmethod_workers (type, method, xmethods);
- /* If source methods are not found in current class, look for them in the
- base classes. We also have to go through the base classes to gather
- extension methods. */
- for (i = TYPE_N_BASECLASSES (type) - 1; i >= 0; i--)
- {
- LONGEST base_offset;
- if (BASETYPE_VIA_VIRTUAL (type, i))
- {
- base_offset = baseclass_offset (type, i,
- value_contents_for_printing (*argp).data (),
- value_offset (*argp) + offset,
- value_address (*argp), *argp);
- }
- else /* Non-virtual base, simply use bit position from debug
- info. */
- {
- base_offset = TYPE_BASECLASS_BITPOS (type, i) / 8;
- }
- find_method_list (argp, method, base_offset + offset,
- TYPE_BASECLASS (type, i), methods,
- xmethods, basetype, boffset);
- }
- }
- /* Return the list of overloaded methods of a specified name. The methods
- could be those GDB finds in the binary, or xmethod. Methods found in
- the binary are returned in METHODS, and xmethods are returned in
- XMETHODS.
- ARGP is a pointer to a pointer to a value (the object).
- METHOD is the method name.
- OFFSET is the offset within the value contents.
- METHODS is the list of matching overloaded instances defined in
- the source language.
- XMETHODS is the vector of matching xmethod workers defined in
- extension languages.
- BASETYPE is set to the type of the base subobject that defines the
- method.
- BOFFSET is the offset of the base subobject which defines the method. */
- static void
- value_find_oload_method_list (struct value **argp, const char *method,
- LONGEST offset,
- gdb::array_view<fn_field> *methods,
- std::vector<xmethod_worker_up> *xmethods,
- struct type **basetype, LONGEST *boffset)
- {
- struct type *t;
- t = check_typedef (value_type (*argp));
- /* Code snarfed from value_struct_elt. */
- while (t->is_pointer_or_reference ())
- {
- *argp = value_ind (*argp);
- /* Don't coerce fn pointer to fn and then back again! */
- if (check_typedef (value_type (*argp))->code () != TYPE_CODE_FUNC)
- *argp = coerce_array (*argp);
- t = check_typedef (value_type (*argp));
- }
- if (t->code () != TYPE_CODE_STRUCT
- && t->code () != TYPE_CODE_UNION)
- error (_("Attempt to extract a component of a "
- "value that is not a struct or union"));
- gdb_assert (methods != NULL && xmethods != NULL);
- /* Clear the lists. */
- *methods = {};
- xmethods->clear ();
- find_method_list (argp, method, 0, t, methods, xmethods,
- basetype, boffset);
- }
- /* Given an array of arguments (ARGS) (which includes an entry for
- "this" in the case of C++ methods), the NAME of a function, and
- whether it's a method or not (METHOD), find the best function that
- matches on the argument types according to the overload resolution
- rules.
- METHOD can be one of three values:
- NON_METHOD for non-member functions.
- METHOD: for member functions.
- BOTH: used for overload resolution of operators where the
- candidates are expected to be either member or non member
- functions. In this case the first argument ARGTYPES
- (representing 'this') is expected to be a reference to the
- target object, and will be dereferenced when attempting the
- non-member search.
- In the case of class methods, the parameter OBJ is an object value
- in which to search for overloaded methods.
- In the case of non-method functions, the parameter FSYM is a symbol
- corresponding to one of the overloaded functions.
- Return value is an integer: 0 -> good match, 10 -> debugger applied
- non-standard coercions, 100 -> incompatible.
- If a method is being searched for, VALP will hold the value.
- If a non-method is being searched for, SYMP will hold the symbol
- for it.
- If a method is being searched for, and it is a static method,
- then STATICP will point to a non-zero value.
- If NO_ADL argument dependent lookup is disabled. This is used to prevent
- ADL overload candidates when performing overload resolution for a fully
- qualified name.
- If NOSIDE is EVAL_AVOID_SIDE_EFFECTS, then OBJP's memory cannot be
- read while picking the best overload match (it may be all zeroes and thus
- not have a vtable pointer), in which case skip virtual function lookup.
- This is ok as typically EVAL_AVOID_SIDE_EFFECTS is only used to determine
- the result type.
- Note: This function does *not* check the value of
- overload_resolution. Caller must check it to see whether overload
- resolution is permitted. */
- int
- find_overload_match (gdb::array_view<value *> args,
- const char *name, enum oload_search_type method,
- struct value **objp, struct symbol *fsym,
- struct value **valp, struct symbol **symp,
- int *staticp, const int no_adl,
- const enum noside noside)
- {
- struct value *obj = (objp ? *objp : NULL);
- struct type *obj_type = obj ? value_type (obj) : NULL;
- /* Index of best overloaded function. */
- int func_oload_champ = -1;
- int method_oload_champ = -1;
- int src_method_oload_champ = -1;
- int ext_method_oload_champ = -1;
- /* The measure for the current best match. */
- badness_vector method_badness;
- badness_vector func_badness;
- badness_vector ext_method_badness;
- badness_vector src_method_badness;
- struct value *temp = obj;
- /* For methods, the list of overloaded methods. */
- gdb::array_view<fn_field> methods;
- /* For non-methods, the list of overloaded function symbols. */
- std::vector<symbol *> functions;
- /* For xmethods, the vector of xmethod workers. */
- std::vector<xmethod_worker_up> xmethods;
- struct type *basetype = NULL;
- LONGEST boffset;
- const char *obj_type_name = NULL;
- const char *func_name = NULL;
- gdb::unique_xmalloc_ptr<char> temp_func;
- enum oload_classification match_quality;
- enum oload_classification method_match_quality = INCOMPATIBLE;
- enum oload_classification src_method_match_quality = INCOMPATIBLE;
- enum oload_classification ext_method_match_quality = INCOMPATIBLE;
- enum oload_classification func_match_quality = INCOMPATIBLE;
- /* Get the list of overloaded methods or functions. */
- if (method == METHOD || method == BOTH)
- {
- gdb_assert (obj);
- /* OBJ may be a pointer value rather than the object itself. */
- obj = coerce_ref (obj);
- while (check_typedef (value_type (obj))->code () == TYPE_CODE_PTR)
- obj = coerce_ref (value_ind (obj));
- obj_type_name = value_type (obj)->name ();
- /* First check whether this is a data member, e.g. a pointer to
- a function. */
- if (check_typedef (value_type (obj))->code () == TYPE_CODE_STRUCT)
- {
- *valp = search_struct_field (name, obj,
- check_typedef (value_type (obj)), 0);
- if (*valp)
- {
- *staticp = 1;
- return 0;
- }
- }
- /* Retrieve the list of methods with the name NAME. */
- value_find_oload_method_list (&temp, name, 0, &methods,
- &xmethods, &basetype, &boffset);
- /* If this is a method only search, and no methods were found
- the search has failed. */
- if (method == METHOD && methods.empty () && xmethods.empty ())
- error (_("Couldn't find method %s%s%s"),
- obj_type_name,
- (obj_type_name && *obj_type_name) ? "::" : "",
- name);
- /* If we are dealing with stub method types, they should have
- been resolved by find_method_list via
- value_find_oload_method_list above. */
- if (!methods.empty ())
- {
- gdb_assert (TYPE_SELF_TYPE (methods[0].type) != NULL);
- src_method_oload_champ
- = find_oload_champ (args,
- methods.size (),
- methods.data (), NULL, NULL,
- &src_method_badness);
- src_method_match_quality = classify_oload_match
- (src_method_badness, args.size (),
- oload_method_static_p (methods.data (), src_method_oload_champ));
- }
- if (!xmethods.empty ())
- {
- ext_method_oload_champ
- = find_oload_champ (args,
- xmethods.size (),
- NULL, xmethods.data (), NULL,
- &ext_method_badness);
- ext_method_match_quality = classify_oload_match (ext_method_badness,
- args.size (), 0);
- }
- if (src_method_oload_champ >= 0 && ext_method_oload_champ >= 0)
- {
- switch (compare_badness (ext_method_badness, src_method_badness))
- {
- case 0: /* Src method and xmethod are equally good. */
- /* If src method and xmethod are equally good, then
- xmethod should be the winner. Hence, fall through to the
- case where a xmethod is better than the source
- method, except when the xmethod match quality is
- non-standard. */
- /* FALLTHROUGH */
- case 1: /* Src method and ext method are incompatible. */
- /* If ext method match is not standard, then let source method
- win. Otherwise, fallthrough to let xmethod win. */
- if (ext_method_match_quality != STANDARD)
- {
- method_oload_champ = src_method_oload_champ;
- method_badness = src_method_badness;
- ext_method_oload_champ = -1;
- method_match_quality = src_method_match_quality;
- break;
- }
- /* FALLTHROUGH */
- case 2: /* Ext method is champion. */
- method_oload_champ = ext_method_oload_champ;
- method_badness = ext_method_badness;
- src_method_oload_champ = -1;
- method_match_quality = ext_method_match_quality;
- break;
- case 3: /* Src method is champion. */
- method_oload_champ = src_method_oload_champ;
- method_badness = src_method_badness;
- ext_method_oload_champ = -1;
- method_match_quality = src_method_match_quality;
- break;
- default:
- gdb_assert_not_reached ("Unexpected overload comparison "
- "result");
- break;
- }
- }
- else if (src_method_oload_champ >= 0)
- {
- method_oload_champ = src_method_oload_champ;
- method_badness = src_method_badness;
- method_match_quality = src_method_match_quality;
- }
- else if (ext_method_oload_champ >= 0)
- {
- method_oload_champ = ext_method_oload_champ;
- method_badness = ext_method_badness;
- method_match_quality = ext_method_match_quality;
- }
- }
- if (method == NON_METHOD || method == BOTH)
- {
- const char *qualified_name = NULL;
- /* If the overload match is being search for both as a method
- and non member function, the first argument must now be
- dereferenced. */
- if (method == BOTH)
- args[0] = value_ind (args[0]);
- if (fsym)
- {
- qualified_name = fsym->natural_name ();
- /* If we have a function with a C++ name, try to extract just
- the function part. Do not try this for non-functions (e.g.
- function pointers). */
- if (qualified_name
- && (check_typedef (fsym->type ())->code ()
- == TYPE_CODE_FUNC))
- {
- temp_func = cp_func_name (qualified_name);
- /* If cp_func_name did not remove anything, the name of the
- symbol did not include scope or argument types - it was
- probably a C-style function. */
- if (temp_func != nullptr)
- {
- if (strcmp (temp_func.get (), qualified_name) == 0)
- func_name = NULL;
- else
- func_name = temp_func.get ();
- }
- }
- }
- else
- {
- func_name = name;
- qualified_name = name;
- }
- /* If there was no C++ name, this must be a C-style function or
- not a function at all. Just return the same symbol. Do the
- same if cp_func_name fails for some reason. */
- if (func_name == NULL)
- {
- *symp = fsym;
- return 0;
- }
- func_oload_champ = find_oload_champ_namespace (args,
- func_name,
- qualified_name,
- &functions,
- &func_badness,
- no_adl);
- if (func_oload_champ >= 0)
- func_match_quality = classify_oload_match (func_badness,
- args.size (), 0);
- }
- /* Did we find a match ? */
- if (method_oload_champ == -1 && func_oload_champ == -1)
- throw_error (NOT_FOUND_ERROR,
- _("No symbol \"%s\" in current context."),
- name);
- /* If we have found both a method match and a function
- match, find out which one is better, and calculate match
- quality. */
- if (method_oload_champ >= 0 && func_oload_champ >= 0)
- {
- switch (compare_badness (func_badness, method_badness))
- {
- case 0: /* Top two contenders are equally good. */
- /* FIXME: GDB does not support the general ambiguous case.
- All candidates should be collected and presented the
- user. */
- error (_("Ambiguous overload resolution"));
- break;
- case 1: /* Incomparable top contenders. */
- /* This is an error incompatible candidates
- should not have been proposed. */
- error (_("Internal error: incompatible "
- "overload candidates proposed"));
- break;
- case 2: /* Function champion. */
- method_oload_champ = -1;
- match_quality = func_match_quality;
- break;
- case 3: /* Method champion. */
- func_oload_champ = -1;
- match_quality = method_match_quality;
- break;
- default:
- error (_("Internal error: unexpected overload comparison result"));
- break;
- }
- }
- else
- {
- /* We have either a method match or a function match. */
- if (method_oload_champ >= 0)
- match_quality = method_match_quality;
- else
- match_quality = func_match_quality;
- }
- if (match_quality == INCOMPATIBLE)
- {
- if (method == METHOD)
- error (_("Cannot resolve method %s%s%s to any overloaded instance"),
- obj_type_name,
- (obj_type_name && *obj_type_name) ? "::" : "",
- name);
- else
- error (_("Cannot resolve function %s to any overloaded instance"),
- func_name);
- }
- else if (match_quality == NON_STANDARD)
- {
- if (method == METHOD)
- warning (_("Using non-standard conversion to match "
- "method %s%s%s to supplied arguments"),
- obj_type_name,
- (obj_type_name && *obj_type_name) ? "::" : "",
- name);
- else
- warning (_("Using non-standard conversion to match "
- "function %s to supplied arguments"),
- func_name);
- }
- if (staticp != NULL)
- *staticp = oload_method_static_p (methods.data (), method_oload_champ);
- if (method_oload_champ >= 0)
- {
- if (src_method_oload_champ >= 0)
- {
- if (TYPE_FN_FIELD_VIRTUAL_P (methods, method_oload_champ)
- && noside != EVAL_AVOID_SIDE_EFFECTS)
- {
- *valp = value_virtual_fn_field (&temp, methods.data (),
- method_oload_champ, basetype,
- boffset);
- }
- else
- *valp = value_fn_field (&temp, methods.data (),
- method_oload_champ, basetype, boffset);
- }
- else
- *valp = value_from_xmethod
- (std::move (xmethods[ext_method_oload_champ]));
- }
- else
- *symp = functions[func_oload_champ];
- if (objp)
- {
- struct type *temp_type = check_typedef (value_type (temp));
- struct type *objtype = check_typedef (obj_type);
- if (temp_type->code () != TYPE_CODE_PTR
- && objtype->is_pointer_or_reference ())
- {
- temp = value_addr (temp);
- }
- *objp = temp;
- }
- switch (match_quality)
- {
- case INCOMPATIBLE:
- return 100;
- case NON_STANDARD:
- return 10;
- default: /* STANDARD */
- return 0;
- }
- }
- /* Find the best overload match, searching for FUNC_NAME in namespaces
- contained in QUALIFIED_NAME until it either finds a good match or
- runs out of namespaces. It stores the overloaded functions in
- *OLOAD_SYMS, and the badness vector in *OLOAD_CHAMP_BV. If NO_ADL,
- argument dependent lookup is not performed. */
- static int
- find_oload_champ_namespace (gdb::array_view<value *> args,
- const char *func_name,
- const char *qualified_name,
- std::vector<symbol *> *oload_syms,
- badness_vector *oload_champ_bv,
- const int no_adl)
- {
- int oload_champ;
- find_oload_champ_namespace_loop (args,
- func_name,
- qualified_name, 0,
- oload_syms, oload_champ_bv,
- &oload_champ,
- no_adl);
- return oload_champ;
- }
- /* Helper function for find_oload_champ_namespace; NAMESPACE_LEN is
- how deep we've looked for namespaces, and the champ is stored in
- OLOAD_CHAMP. The return value is 1 if the champ is a good one, 0
- if it isn't. Other arguments are the same as in
- find_oload_champ_namespace. */
- static int
- find_oload_champ_namespace_loop (gdb::array_view<value *> args,
- const char *func_name,
- const char *qualified_name,
- int namespace_len,
- std::vector<symbol *> *oload_syms,
- badness_vector *oload_champ_bv,
- int *oload_champ,
- const int no_adl)
- {
- int next_namespace_len = namespace_len;
- int searched_deeper = 0;
- int new_oload_champ;
- char *new_namespace;
- if (next_namespace_len != 0)
- {
- gdb_assert (qualified_name[next_namespace_len] == ':');
- next_namespace_len += 2;
- }
- next_namespace_len +=
- cp_find_first_component (qualified_name + next_namespace_len);
- /* First, see if we have a deeper namespace we can search in.
- If we get a good match there, use it. */
- if (qualified_name[next_namespace_len] == ':')
- {
- searched_deeper = 1;
- if (find_oload_champ_namespace_loop (args,
- func_name, qualified_name,
- next_namespace_len,
- oload_syms, oload_champ_bv,
- oload_champ, no_adl))
- {
- return 1;
- }
- };
- /* If we reach here, either we're in the deepest namespace or we
- didn't find a good match in a deeper namespace. But, in the
- latter case, we still have a bad match in a deeper namespace;
- note that we might not find any match at all in the current
- namespace. (There's always a match in the deepest namespace,
- because this overload mechanism only gets called if there's a
- function symbol to start off with.) */
- new_namespace = (char *) alloca (namespace_len + 1);
- strncpy (new_namespace, qualified_name, namespace_len);
- new_namespace[namespace_len] = '\0';
- std::vector<symbol *> new_oload_syms
- = make_symbol_overload_list (func_name, new_namespace);
- /* If we have reached the deepest level perform argument
- determined lookup. */
- if (!searched_deeper && !no_adl)
- {
- int ix;
- struct type **arg_types;
- /* Prepare list of argument types for overload resolution. */
- arg_types = (struct type **)
- alloca (args.size () * (sizeof (struct type *)));
- for (ix = 0; ix < args.size (); ix++)
- arg_types[ix] = value_type (args[ix]);
- add_symbol_overload_list_adl ({arg_types, args.size ()}, func_name,
- &new_oload_syms);
- }
- badness_vector new_oload_champ_bv;
- new_oload_champ = find_oload_champ (args,
- new_oload_syms.size (),
- NULL, NULL, new_oload_syms.data (),
- &new_oload_champ_bv);
- /* Case 1: We found a good match. Free earlier matches (if any),
- and return it. Case 2: We didn't find a good match, but we're
- not the deepest function. Then go with the bad match that the
- deeper function found. Case 3: We found a bad match, and we're
- the deepest function. Then return what we found, even though
- it's a bad match. */
- if (new_oload_champ != -1
- && classify_oload_match (new_oload_champ_bv, args.size (), 0) == STANDARD)
- {
- *oload_syms = std::move (new_oload_syms);
- *oload_champ = new_oload_champ;
- *oload_champ_bv = std::move (new_oload_champ_bv);
- return 1;
- }
- else if (searched_deeper)
- {
- return 0;
- }
- else
- {
- *oload_syms = std::move (new_oload_syms);
- *oload_champ = new_oload_champ;
- *oload_champ_bv = std::move (new_oload_champ_bv);
- return 0;
- }
- }
- /* Look for a function to take ARGS. Find the best match from among
- the overloaded methods or functions given by METHODS or FUNCTIONS
- or XMETHODS, respectively. One, and only one of METHODS, FUNCTIONS
- and XMETHODS can be non-NULL.
- NUM_FNS is the length of the array pointed at by METHODS, FUNCTIONS
- or XMETHODS, whichever is non-NULL.
- Return the index of the best match; store an indication of the
- quality of the match in OLOAD_CHAMP_BV. */
- static int
- find_oload_champ (gdb::array_view<value *> args,
- size_t num_fns,
- fn_field *methods,
- xmethod_worker_up *xmethods,
- symbol **functions,
- badness_vector *oload_champ_bv)
- {
- /* A measure of how good an overloaded instance is. */
- badness_vector bv;
- /* Index of best overloaded function. */
- int oload_champ = -1;
- /* Current ambiguity state for overload resolution. */
- int oload_ambiguous = 0;
- /* 0 => no ambiguity, 1 => two good funcs, 2 => incomparable funcs. */
- /* A champion can be found among methods alone, or among functions
- alone, or in xmethods alone, but not in more than one of these
- groups. */
- gdb_assert ((methods != NULL) + (functions != NULL) + (xmethods != NULL)
- == 1);
- /* Consider each candidate in turn. */
- for (size_t ix = 0; ix < num_fns; ix++)
- {
- int jj;
- int static_offset = 0;
- std::vector<type *> parm_types;
- if (xmethods != NULL)
- parm_types = xmethods[ix]->get_arg_types ();
- else
- {
- size_t nparms;
- if (methods != NULL)
- {
- nparms = TYPE_FN_FIELD_TYPE (methods, ix)->num_fields ();
- static_offset = oload_method_static_p (methods, ix);
- }
- else
- nparms = functions[ix]->type ()->num_fields ();
- parm_types.reserve (nparms);
- for (jj = 0; jj < nparms; jj++)
- {
- type *t = (methods != NULL
- ? (TYPE_FN_FIELD_ARGS (methods, ix)[jj].type ())
- : functions[ix]->type ()->field (jj).type ());
- parm_types.push_back (t);
- }
- }
- /* Compare parameter types to supplied argument types. Skip
- THIS for static methods. */
- bv = rank_function (parm_types,
- args.slice (static_offset));
- if (overload_debug)
- {
- if (methods != NULL)
- gdb_printf (gdb_stderr,
- "Overloaded method instance %s, # of parms %d\n",
- methods[ix].physname, (int) parm_types.size ());
- else if (xmethods != NULL)
- gdb_printf (gdb_stderr,
- "Xmethod worker, # of parms %d\n",
- (int) parm_types.size ());
- else
- gdb_printf (gdb_stderr,
- "Overloaded function instance "
- "%s # of parms %d\n",
- functions[ix]->demangled_name (),
- (int) parm_types.size ());
- gdb_printf (gdb_stderr,
- "...Badness of length : {%d, %d}\n",
- bv[0].rank, bv[0].subrank);
- for (jj = 1; jj < bv.size (); jj++)
- gdb_printf (gdb_stderr,
- "...Badness of arg %d : {%d, %d}\n",
- jj, bv[jj].rank, bv[jj].subrank);
- }
- if (oload_champ_bv->empty ())
- {
- *oload_champ_bv = std::move (bv);
- oload_champ = 0;
- }
- else /* See whether current candidate is better or worse than
- previous best. */
- switch (compare_badness (bv, *oload_champ_bv))
- {
- case 0: /* Top two contenders are equally good. */
- oload_ambiguous = 1;
- break;
- case 1: /* Incomparable top contenders. */
- oload_ambiguous = 2;
- break;
- case 2: /* New champion, record details. */
- *oload_champ_bv = std::move (bv);
- oload_ambiguous = 0;
- oload_champ = ix;
- break;
- case 3:
- default:
- break;
- }
- if (overload_debug)
- gdb_printf (gdb_stderr, "Overload resolution "
- "champion is %d, ambiguous? %d\n",
- oload_champ, oload_ambiguous);
- }
- return oload_champ;
- }
- /* Return 1 if we're looking at a static method, 0 if we're looking at
- a non-static method or a function that isn't a method. */
- static int
- oload_method_static_p (struct fn_field *fns_ptr, int index)
- {
- if (fns_ptr && index >= 0 && TYPE_FN_FIELD_STATIC_P (fns_ptr, index))
- return 1;
- else
- return 0;
- }
- /* Check how good an overload match OLOAD_CHAMP_BV represents. */
- static enum oload_classification
- classify_oload_match (const badness_vector &oload_champ_bv,
- int nargs,
- int static_offset)
- {
- int ix;
- enum oload_classification worst = STANDARD;
- for (ix = 1; ix <= nargs - static_offset; ix++)
- {
- /* If this conversion is as bad as INCOMPATIBLE_TYPE_BADNESS
- or worse return INCOMPATIBLE. */
- if (compare_ranks (oload_champ_bv[ix],
- INCOMPATIBLE_TYPE_BADNESS) <= 0)
- return INCOMPATIBLE; /* Truly mismatched types. */
- /* Otherwise If this conversion is as bad as
- NS_POINTER_CONVERSION_BADNESS or worse return NON_STANDARD. */
- else if (compare_ranks (oload_champ_bv[ix],
- NS_POINTER_CONVERSION_BADNESS) <= 0)
- worst = NON_STANDARD; /* Non-standard type conversions
- needed. */
- }
- /* If no INCOMPATIBLE classification was found, return the worst one
- that was found (if any). */
- return worst;
- }
- /* C++: return 1 is NAME is a legitimate name for the destructor of
- type TYPE. If TYPE does not have a destructor, or if NAME is
- inappropriate for TYPE, an error is signaled. Parameter TYPE should not yet
- have CHECK_TYPEDEF applied, this function will apply it itself. */
- int
- destructor_name_p (const char *name, struct type *type)
- {
- if (name[0] == '~')
- {
- const char *dname = type_name_or_error (type);
- const char *cp = strchr (dname, '<');
- unsigned int len;
- /* Do not compare the template part for template classes. */
- if (cp == NULL)
- len = strlen (dname);
- else
- len = cp - dname;
- if (strlen (name + 1) != len || strncmp (dname, name + 1, len) != 0)
- error (_("name of destructor must equal name of class"));
- else
- return 1;
- }
- return 0;
- }
- /* Find an enum constant named NAME in TYPE. TYPE must be an "enum
- class". If the name is found, return a value representing it;
- otherwise throw an exception. */
- static struct value *
- enum_constant_from_type (struct type *type, const char *name)
- {
- int i;
- int name_len = strlen (name);
- gdb_assert (type->code () == TYPE_CODE_ENUM
- && type->is_declared_class ());
- for (i = TYPE_N_BASECLASSES (type); i < type->num_fields (); ++i)
- {
- const char *fname = type->field (i).name ();
- int len;
- if (type->field (i).loc_kind () != FIELD_LOC_KIND_ENUMVAL
- || fname == NULL)
- continue;
- /* Look for the trailing "::NAME", since enum class constant
- names are qualified here. */
- len = strlen (fname);
- if (len + 2 >= name_len
- && fname[len - name_len - 2] == ':'
- && fname[len - name_len - 1] == ':'
- && strcmp (&fname[len - name_len], name) == 0)
- return value_from_longest (type, type->field (i).loc_enumval ());
- }
- error (_("no constant named \"%s\" in enum \"%s\""),
- name, type->name ());
- }
- /* C++: Given an aggregate type CURTYPE, and a member name NAME,
- return the appropriate member (or the address of the member, if
- WANT_ADDRESS). This function is used to resolve user expressions
- of the form "DOMAIN::NAME". For more details on what happens, see
- the comment before value_struct_elt_for_reference. */
- struct value *
- value_aggregate_elt (struct type *curtype, const char *name,
- struct type *expect_type, int want_address,
- enum noside noside)
- {
- switch (curtype->code ())
- {
- case TYPE_CODE_STRUCT:
- case TYPE_CODE_UNION:
- return value_struct_elt_for_reference (curtype, 0, curtype,
- name, expect_type,
- want_address, noside);
- case TYPE_CODE_NAMESPACE:
- return value_namespace_elt (curtype, name,
- want_address, noside);
- case TYPE_CODE_ENUM:
- return enum_constant_from_type (curtype, name);
- default:
- internal_error (__FILE__, __LINE__,
- _("non-aggregate type in value_aggregate_elt"));
- }
- }
- /* Compares the two method/function types T1 and T2 for "equality"
- with respect to the methods' parameters. If the types of the
- two parameter lists are the same, returns 1; 0 otherwise. This
- comparison may ignore any artificial parameters in T1 if
- SKIP_ARTIFICIAL is non-zero. This function will ALWAYS skip
- the first artificial parameter in T1, assumed to be a 'this' pointer.
- The type T2 is expected to have come from make_params (in eval.c). */
- static int
- compare_parameters (struct type *t1, struct type *t2, int skip_artificial)
- {
- int start = 0;
- if (t1->num_fields () > 0 && TYPE_FIELD_ARTIFICIAL (t1, 0))
- ++start;
- /* If skipping artificial fields, find the first real field
- in T1. */
- if (skip_artificial)
- {
- while (start < t1->num_fields ()
- && TYPE_FIELD_ARTIFICIAL (t1, start))
- ++start;
- }
- /* Now compare parameters. */
- /* Special case: a method taking void. T1 will contain no
- non-artificial fields, and T2 will contain TYPE_CODE_VOID. */
- if ((t1->num_fields () - start) == 0 && t2->num_fields () == 1
- && t2->field (0).type ()->code () == TYPE_CODE_VOID)
- return 1;
- if ((t1->num_fields () - start) == t2->num_fields ())
- {
- int i;
- for (i = 0; i < t2->num_fields (); ++i)
- {
- if (compare_ranks (rank_one_type (t1->field (start + i).type (),
- t2->field (i).type (), NULL),
- EXACT_MATCH_BADNESS) != 0)
- return 0;
- }
- return 1;
- }
- return 0;
- }
- /* C++: Given an aggregate type VT, and a class type CLS, search
- recursively for CLS using value V; If found, store the offset
- which is either fetched from the virtual base pointer if CLS
- is virtual or accumulated offset of its parent classes if
- CLS is non-virtual in *BOFFS, set ISVIRT to indicate if CLS
- is virtual, and return true. If not found, return false. */
- static bool
- get_baseclass_offset (struct type *vt, struct type *cls,
- struct value *v, int *boffs, bool *isvirt)
- {
- for (int i = 0; i < TYPE_N_BASECLASSES (vt); i++)
- {
- struct type *t = vt->field (i).type ();
- if (types_equal (t, cls))
- {
- if (BASETYPE_VIA_VIRTUAL (vt, i))
- {
- const gdb_byte *adr = value_contents_for_printing (v).data ();
- *boffs = baseclass_offset (vt, i, adr, value_offset (v),
- value_as_long (v), v);
- *isvirt = true;
- }
- else
- *isvirt = false;
- return true;
- }
- if (get_baseclass_offset (check_typedef (t), cls, v, boffs, isvirt))
- {
- if (*isvirt == false) /* Add non-virtual base offset. */
- {
- const gdb_byte *adr = value_contents_for_printing (v).data ();
- *boffs += baseclass_offset (vt, i, adr, value_offset (v),
- value_as_long (v), v);
- }
- return true;
- }
- }
- return false;
- }
- /* C++: Given an aggregate type CURTYPE, and a member name NAME,
- return the address of this member as a "pointer to member" type.
- If INTYPE is non-null, then it will be the type of the member we
- are looking for. This will help us resolve "pointers to member
- functions". This function is used to resolve user expressions of
- the form "DOMAIN::NAME". */
- static struct value *
- value_struct_elt_for_reference (struct type *domain, int offset,
- struct type *curtype, const char *name,
- struct type *intype,
- int want_address,
- enum noside noside)
- {
- struct type *t = check_typedef (curtype);
- int i;
- struct value *result;
- if (t->code () != TYPE_CODE_STRUCT
- && t->code () != TYPE_CODE_UNION)
- error (_("Internal error: non-aggregate type "
- "to value_struct_elt_for_reference"));
- for (i = t->num_fields () - 1; i >= TYPE_N_BASECLASSES (t); i--)
- {
- const char *t_field_name = t->field (i).name ();
- if (t_field_name && strcmp (t_field_name, name) == 0)
- {
- if (field_is_static (&t->field (i)))
- {
- struct value *v = value_static_field (t, i);
- if (want_address)
- v = value_addr (v);
- return v;
- }
- if (TYPE_FIELD_PACKED (t, i))
- error (_("pointers to bitfield members not allowed"));
- if (want_address)
- return value_from_longest
- (lookup_memberptr_type (t->field (i).type (), domain),
- offset + (LONGEST) (t->field (i).loc_bitpos () >> 3));
- else if (noside != EVAL_NORMAL)
- return allocate_value (t->field (i).type ());
- else
- {
- /* Try to evaluate NAME as a qualified name with implicit
- this pointer. In this case, attempt to return the
- equivalent to `this->*(&TYPE::NAME)'. */
- struct value *v = value_of_this_silent (current_language);
- if (v != NULL)
- {
- struct value *ptr, *this_v = v;
- long mem_offset;
- struct type *type, *tmp;
- ptr = value_aggregate_elt (domain, name, NULL, 1, noside);
- type = check_typedef (value_type (ptr));
- gdb_assert (type != NULL
- && type->code () == TYPE_CODE_MEMBERPTR);
- tmp = lookup_pointer_type (TYPE_SELF_TYPE (type));
- v = value_cast_pointers (tmp, v, 1);
- mem_offset = value_as_long (ptr);
- if (domain != curtype)
- {
- /* Find class offset of type CURTYPE from either its
- parent type DOMAIN or the type of implied this. */
- int boff = 0;
- bool isvirt = false;
- if (get_baseclass_offset (domain, curtype, v, &boff,
- &isvirt))
- mem_offset += boff;
- else
- {
- struct type *p = check_typedef (value_type (this_v));
- p = check_typedef (TYPE_TARGET_TYPE (p));
- if (get_baseclass_offset (p, curtype, this_v,
- &boff, &isvirt))
- mem_offset += boff;
- }
- }
- tmp = lookup_pointer_type (TYPE_TARGET_TYPE (type));
- result = value_from_pointer (tmp,
- value_as_long (v) + mem_offset);
- return value_ind (result);
- }
- error (_("Cannot reference non-static field \"%s\""), name);
- }
- }
- }
- /* C++: If it was not found as a data field, then try to return it
- as a pointer to a method. */
- /* Perform all necessary dereferencing. */
- while (intype && intype->code () == TYPE_CODE_PTR)
- intype = TYPE_TARGET_TYPE (intype);
- for (i = TYPE_NFN_FIELDS (t) - 1; i >= 0; --i)
- {
- const char *t_field_name = TYPE_FN_FIELDLIST_NAME (t, i);
- if (t_field_name && strcmp (t_field_name, name) == 0)
- {
- int j;
- int len = TYPE_FN_FIELDLIST_LENGTH (t, i);
- struct fn_field *f = TYPE_FN_FIELDLIST1 (t, i);
- check_stub_method_group (t, i);
- if (intype)
- {
- for (j = 0; j < len; ++j)
- {
- if (TYPE_CONST (intype) != TYPE_FN_FIELD_CONST (f, j))
- continue;
- if (TYPE_VOLATILE (intype) != TYPE_FN_FIELD_VOLATILE (f, j))
- continue;
- if (compare_parameters (TYPE_FN_FIELD_TYPE (f, j), intype, 0)
- || compare_parameters (TYPE_FN_FIELD_TYPE (f, j),
- intype, 1))
- break;
- }
- if (j == len)
- error (_("no member function matches "
- "that type instantiation"));
- }
- else
- {
- int ii;
- j = -1;
- for (ii = 0; ii < len; ++ii)
- {
- /* Skip artificial methods. This is necessary if,
- for example, the user wants to "print
- subclass::subclass" with only one user-defined
- constructor. There is no ambiguity in this case.
- We are careful here to allow artificial methods
- if they are the unique result. */
- if (TYPE_FN_FIELD_ARTIFICIAL (f, ii))
- {
- if (j == -1)
- j = ii;
- continue;
- }
- /* Desired method is ambiguous if more than one
- method is defined. */
- if (j != -1 && !TYPE_FN_FIELD_ARTIFICIAL (f, j))
- error (_("non-unique member `%s' requires "
- "type instantiation"), name);
- j = ii;
- }
- if (j == -1)
- error (_("no matching member function"));
- }
- if (TYPE_FN_FIELD_STATIC_P (f, j))
- {
- struct symbol *s =
- lookup_symbol (TYPE_FN_FIELD_PHYSNAME (f, j),
- 0, VAR_DOMAIN, 0).symbol;
- if (s == NULL)
- return NULL;
- if (want_address)
- return value_addr (read_var_value (s, 0, 0));
- else
- return read_var_value (s, 0, 0);
- }
- if (TYPE_FN_FIELD_VIRTUAL_P (f, j))
- {
- if (want_address)
- {
- result = allocate_value
- (lookup_methodptr_type (TYPE_FN_FIELD_TYPE (f, j)));
- cplus_make_method_ptr (value_type (result),
- value_contents_writeable (result).data (),
- TYPE_FN_FIELD_VOFFSET (f, j), 1);
- }
- else if (noside == EVAL_AVOID_SIDE_EFFECTS)
- return allocate_value (TYPE_FN_FIELD_TYPE (f, j));
- else
- error (_("Cannot reference virtual member function \"%s\""),
- name);
- }
- else
- {
- struct symbol *s =
- lookup_symbol (TYPE_FN_FIELD_PHYSNAME (f, j),
- 0, VAR_DOMAIN, 0).symbol;
- if (s == NULL)
- return NULL;
- struct value *v = read_var_value (s, 0, 0);
- if (!want_address)
- result = v;
- else
- {
- result = allocate_value (lookup_methodptr_type (TYPE_FN_FIELD_TYPE (f, j)));
- cplus_make_method_ptr (value_type (result),
- value_contents_writeable (result).data (),
- value_address (v), 0);
- }
- }
- return result;
- }
- }
- for (i = TYPE_N_BASECLASSES (t) - 1; i >= 0; i--)
- {
- struct value *v;
- int base_offset;
- if (BASETYPE_VIA_VIRTUAL (t, i))
- base_offset = 0;
- else
- base_offset = TYPE_BASECLASS_BITPOS (t, i) / 8;
- v = value_struct_elt_for_reference (domain,
- offset + base_offset,
- TYPE_BASECLASS (t, i),
- name, intype,
- want_address, noside);
- if (v)
- return v;
- }
- /* As a last chance, pretend that CURTYPE is a namespace, and look
- it up that way; this (frequently) works for types nested inside
- classes. */
- return value_maybe_namespace_elt (curtype, name,
- want_address, noside);
- }
- /* C++: Return the member NAME of the namespace given by the type
- CURTYPE. */
- static struct value *
- value_namespace_elt (const struct type *curtype,
- const char *name, int want_address,
- enum noside noside)
- {
- struct value *retval = value_maybe_namespace_elt (curtype, name,
- want_address,
- noside);
- if (retval == NULL)
- error (_("No symbol \"%s\" in namespace \"%s\"."),
- name, curtype->name ());
- return retval;
- }
- /* A helper function used by value_namespace_elt and
- value_struct_elt_for_reference. It looks up NAME inside the
- context CURTYPE; this works if CURTYPE is a namespace or if CURTYPE
- is a class and NAME refers to a type in CURTYPE itself (as opposed
- to, say, some base class of CURTYPE). */
- static struct value *
- value_maybe_namespace_elt (const struct type *curtype,
- const char *name, int want_address,
- enum noside noside)
- {
- const char *namespace_name = curtype->name ();
- struct block_symbol sym;
- struct value *result;
- sym = cp_lookup_symbol_namespace (namespace_name, name,
- get_selected_block (0), VAR_DOMAIN);
- if (sym.symbol == NULL)
- return NULL;
- else if ((noside == EVAL_AVOID_SIDE_EFFECTS)
- && (sym.symbol->aclass () == LOC_TYPEDEF))
- result = allocate_value (sym.symbol->type ());
- else
- result = value_of_variable (sym.symbol, sym.block);
- if (want_address)
- result = value_addr (result);
- return result;
- }
- /* Given a pointer or a reference value V, find its real (RTTI) type.
- Other parameters FULL, TOP, USING_ENC as with value_rtti_type()
- and refer to the values computed for the object pointed to. */
- struct type *
- value_rtti_indirect_type (struct value *v, int *full,
- LONGEST *top, int *using_enc)
- {
- struct value *target = NULL;
- struct type *type, *real_type, *target_type;
- type = value_type (v);
- type = check_typedef (type);
- if (TYPE_IS_REFERENCE (type))
- target = coerce_ref (v);
- else if (type->code () == TYPE_CODE_PTR)
- {
- try
- {
- target = value_ind (v);
- }
- catch (const gdb_exception_error &except)
- {
- if (except.error == MEMORY_ERROR)
- {
- /* value_ind threw a memory error. The pointer is NULL or
- contains an uninitialized value: we can't determine any
- type. */
- return NULL;
- }
- throw;
- }
- }
- else
- return NULL;
- real_type = value_rtti_type (target, full, top, using_enc);
- if (real_type)
- {
- /* Copy qualifiers to the referenced object. */
- target_type = value_type (target);
- real_type = make_cv_type (TYPE_CONST (target_type),
- TYPE_VOLATILE (target_type), real_type, NULL);
- if (TYPE_IS_REFERENCE (type))
- real_type = lookup_reference_type (real_type, type->code ());
- else if (type->code () == TYPE_CODE_PTR)
- real_type = lookup_pointer_type (real_type);
- else
- internal_error (__FILE__, __LINE__, _("Unexpected value type."));
- /* Copy qualifiers to the pointer/reference. */
- real_type = make_cv_type (TYPE_CONST (type), TYPE_VOLATILE (type),
- real_type, NULL);
- }
- return real_type;
- }
- /* Given a value pointed to by ARGP, check its real run-time type, and
- if that is different from the enclosing type, create a new value
- using the real run-time type as the enclosing type (and of the same
- type as ARGP) and return it, with the embedded offset adjusted to
- be the correct offset to the enclosed object. RTYPE is the type,
- and XFULL, XTOP, and XUSING_ENC are the other parameters, computed
- by value_rtti_type(). If these are available, they can be supplied
- and a second call to value_rtti_type() is avoided. (Pass RTYPE ==
- NULL if they're not available. */
- struct value *
- value_full_object (struct value *argp,
- struct type *rtype,
- int xfull, int xtop,
- int xusing_enc)
- {
- struct type *real_type;
- int full = 0;
- LONGEST top = -1;
- int using_enc = 0;
- struct value *new_val;
- if (rtype)
- {
- real_type = rtype;
- full = xfull;
- top = xtop;
- using_enc = xusing_enc;
- }
- else
- real_type = value_rtti_type (argp, &full, &top, &using_enc);
- /* If no RTTI data, or if object is already complete, do nothing. */
- if (!real_type || real_type == value_enclosing_type (argp))
- return argp;
- /* In a destructor we might see a real type that is a superclass of
- the object's type. In this case it is better to leave the object
- as-is. */
- if (full
- && TYPE_LENGTH (real_type) < TYPE_LENGTH (value_enclosing_type (argp)))
- return argp;
- /* If we have the full object, but for some reason the enclosing
- type is wrong, set it. */
- /* pai: FIXME -- sounds iffy */
- if (full)
- {
- argp = value_copy (argp);
- set_value_enclosing_type (argp, real_type);
- return argp;
- }
- /* Check if object is in memory. */
- if (VALUE_LVAL (argp) != lval_memory)
- {
- warning (_("Couldn't retrieve complete object of RTTI "
- "type %s; object may be in register(s)."),
- real_type->name ());
- return argp;
- }
- /* All other cases -- retrieve the complete object. */
- /* Go back by the computed top_offset from the beginning of the
- object, adjusting for the embedded offset of argp if that's what
- value_rtti_type used for its computation. */
- new_val = value_at_lazy (real_type, value_address (argp) - top +
- (using_enc ? 0 : value_embedded_offset (argp)));
- deprecated_set_value_type (new_val, value_type (argp));
- set_value_embedded_offset (new_val, (using_enc
- ? top + value_embedded_offset (argp)
- : top));
- return new_val;
- }
- /* Return the value of the local variable, if one exists. Throw error
- otherwise, such as if the request is made in an inappropriate context. */
- struct value *
- value_of_this (const struct language_defn *lang)
- {
- struct block_symbol sym;
- const struct block *b;
- struct frame_info *frame;
- if (lang->name_of_this () == NULL)
- error (_("no `this' in current language"));
- frame = get_selected_frame (_("no frame selected"));
- b = get_frame_block (frame, NULL);
- sym = lookup_language_this (lang, b);
- if (sym.symbol == NULL)
- error (_("current stack frame does not contain a variable named `%s'"),
- lang->name_of_this ());
- return read_var_value (sym.symbol, sym.block, frame);
- }
- /* Return the value of the local variable, if one exists. Return NULL
- otherwise. Never throw error. */
- struct value *
- value_of_this_silent (const struct language_defn *lang)
- {
- struct value *ret = NULL;
- try
- {
- ret = value_of_this (lang);
- }
- catch (const gdb_exception_error &except)
- {
- }
- return ret;
- }
- /* Create a slice (sub-string, sub-array) of ARRAY, that is LENGTH
- elements long, starting at LOWBOUND. The result has the same lower
- bound as the original ARRAY. */
- struct value *
- value_slice (struct value *array, int lowbound, int length)
- {
- struct type *slice_range_type, *slice_type, *range_type;
- LONGEST lowerbound, upperbound;
- struct value *slice;
- struct type *array_type;
- array_type = check_typedef (value_type (array));
- if (array_type->code () != TYPE_CODE_ARRAY
- && array_type->code () != TYPE_CODE_STRING)
- error (_("cannot take slice of non-array"));
- if (type_not_allocated (array_type))
- error (_("array not allocated"));
- if (type_not_associated (array_type))
- error (_("array not associated"));
- range_type = array_type->index_type ();
- if (!get_discrete_bounds (range_type, &lowerbound, &upperbound))
- error (_("slice from bad array or bitstring"));
- if (lowbound < lowerbound || length < 0
- || lowbound + length - 1 > upperbound)
- error (_("slice out of range"));
- /* FIXME-type-allocation: need a way to free this type when we are
- done with it. */
- slice_range_type = create_static_range_type (NULL,
- TYPE_TARGET_TYPE (range_type),
- lowbound,
- lowbound + length - 1);
- {
- struct type *element_type = TYPE_TARGET_TYPE (array_type);
- LONGEST offset
- = (lowbound - lowerbound) * TYPE_LENGTH (check_typedef (element_type));
- slice_type = create_array_type (NULL,
- element_type,
- slice_range_type);
- slice_type->set_code (array_type->code ());
- if (VALUE_LVAL (array) == lval_memory && value_lazy (array))
- slice = allocate_value_lazy (slice_type);
- else
- {
- slice = allocate_value (slice_type);
- value_contents_copy (slice, 0, array, offset,
- type_length_units (slice_type));
- }
- set_value_component_location (slice, array);
- set_value_offset (slice, value_offset (array) + offset);
- }
- return slice;
- }
- /* See value.h. */
- struct value *
- value_literal_complex (struct value *arg1,
- struct value *arg2,
- struct type *type)
- {
- struct value *val;
- struct type *real_type = TYPE_TARGET_TYPE (type);
- val = allocate_value (type);
- arg1 = value_cast (real_type, arg1);
- arg2 = value_cast (real_type, arg2);
- int len = TYPE_LENGTH (real_type);
- copy (value_contents (arg1),
- value_contents_raw (val).slice (0, len));
- copy (value_contents (arg2),
- value_contents_raw (val).slice (len, len));
- return val;
- }
- /* See value.h. */
- struct value *
- value_real_part (struct value *value)
- {
- struct type *type = check_typedef (value_type (value));
- struct type *ttype = TYPE_TARGET_TYPE (type);
- gdb_assert (type->code () == TYPE_CODE_COMPLEX);
- return value_from_component (value, ttype, 0);
- }
- /* See value.h. */
- struct value *
- value_imaginary_part (struct value *value)
- {
- struct type *type = check_typedef (value_type (value));
- struct type *ttype = TYPE_TARGET_TYPE (type);
- gdb_assert (type->code () == TYPE_CODE_COMPLEX);
- return value_from_component (value, ttype,
- TYPE_LENGTH (check_typedef (ttype)));
- }
- /* Cast a value into the appropriate complex data type. */
- static struct value *
- cast_into_complex (struct type *type, struct value *val)
- {
- struct type *real_type = TYPE_TARGET_TYPE (type);
- if (value_type (val)->code () == TYPE_CODE_COMPLEX)
- {
- struct type *val_real_type = TYPE_TARGET_TYPE (value_type (val));
- struct value *re_val = allocate_value (val_real_type);
- struct value *im_val = allocate_value (val_real_type);
- int len = TYPE_LENGTH (val_real_type);
- copy (value_contents (val).slice (0, len),
- value_contents_raw (re_val));
- copy (value_contents (val).slice (len, len),
- value_contents_raw (im_val));
- return value_literal_complex (re_val, im_val, type);
- }
- else if (value_type (val)->code () == TYPE_CODE_FLT
- || value_type (val)->code () == TYPE_CODE_INT)
- return value_literal_complex (val,
- value_zero (real_type, not_lval),
- type);
- else
- error (_("cannot cast non-number to complex"));
- }
- void _initialize_valops ();
- void
- _initialize_valops ()
- {
- add_setshow_boolean_cmd ("overload-resolution", class_support,
- &overload_resolution, _("\
- Set overload resolution in evaluating C++ functions."), _("\
- Show overload resolution in evaluating C++ functions."),
- NULL, NULL,
- show_overload_resolution,
- &setlist, &showlist);
- overload_resolution = 1;
- }
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