mirror of
https://sourceware.org/git/binutils-gdb.git
synced 2024-12-21 04:42:53 +08:00
7c22600aab
This adds some initial support for variant parts to gdbtypes.h. A variant part is represented as a union. The union has a flag indicating that it has a discriminant, and information about the discriminant is attached using the dynamic property system. 2018-02-26 Tom Tromey <tom@tromey.com> * value.h (value_union_variant): Declare. * valops.c (value_union_variant): New function. * gdbtypes.h (TYPE_FLAG_DISCRIMINATED_UNION): New macro. (struct discriminant_info): New. (enum dynamic_prop_node_kind) <DYN_PROP_DISCRIMINATED>: New enumerator. (struct main_type) <flag_discriminated_union>: New field.
1181 lines
43 KiB
C++
1181 lines
43 KiB
C++
/* Definitions for values of C expressions, for GDB.
|
||
|
||
Copyright (C) 1986-2018 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/>. */
|
||
|
||
#if !defined (VALUE_H)
|
||
#define VALUE_H 1
|
||
|
||
#include "frame.h" /* For struct frame_id. */
|
||
#include "extension.h"
|
||
|
||
struct block;
|
||
struct expression;
|
||
struct regcache;
|
||
struct symbol;
|
||
struct type;
|
||
struct ui_file;
|
||
struct language_defn;
|
||
struct value_print_options;
|
||
|
||
/* Values can be partially 'optimized out' and/or 'unavailable'.
|
||
These are distinct states and have different string representations
|
||
and related error strings.
|
||
|
||
'unavailable' has a specific meaning in this context. It means the
|
||
value exists in the program (at the machine level), but GDB has no
|
||
means to get to it. Such a value is normally printed as
|
||
<unavailable>. Examples of how to end up with an unavailable value
|
||
would be:
|
||
|
||
- We're inspecting a traceframe, and the memory or registers the
|
||
debug information says the value lives on haven't been collected.
|
||
|
||
- We're inspecting a core dump, the memory or registers the debug
|
||
information says the value lives aren't present in the dump
|
||
(that is, we have a partial/trimmed core dump, or we don't fully
|
||
understand/handle the core dump's format).
|
||
|
||
- We're doing live debugging, but the debug API has no means to
|
||
get at where the value lives in the machine, like e.g., ptrace
|
||
not having access to some register or register set.
|
||
|
||
- Any other similar scenario.
|
||
|
||
OTOH, "optimized out" is about what the compiler decided to generate
|
||
(or not generate). A chunk of a value that was optimized out does
|
||
not actually exist in the program. There's no way to get at it
|
||
short of compiling the program differently.
|
||
|
||
A register that has not been saved in a frame is likewise considered
|
||
optimized out, except not-saved registers have a different string
|
||
representation and related error strings. E.g., we'll print them as
|
||
<not-saved> instead of <optimized out>, as in:
|
||
|
||
(gdb) p/x $rax
|
||
$1 = <not saved>
|
||
(gdb) info registers rax
|
||
rax <not saved>
|
||
|
||
If the debug info describes a variable as being in such a register,
|
||
we'll still print the variable as <optimized out>. IOW, <not saved>
|
||
is reserved for inspecting registers at the machine level.
|
||
|
||
When comparing value contents, optimized out chunks, unavailable
|
||
chunks, and valid contents data are all considered different. See
|
||
value_contents_eq for more info.
|
||
*/
|
||
|
||
/* The structure which defines the type of a value. It should never
|
||
be possible for a program lval value to survive over a call to the
|
||
inferior (i.e. to be put into the history list or an internal
|
||
variable). */
|
||
|
||
struct value;
|
||
|
||
/* Values are stored in a chain, so that they can be deleted easily
|
||
over calls to the inferior. Values assigned to internal variables,
|
||
put into the value history or exposed to Python are taken off this
|
||
list. */
|
||
|
||
struct value *value_next (const struct value *);
|
||
|
||
/* Type of the value. */
|
||
|
||
extern struct type *value_type (const struct value *);
|
||
|
||
/* Return the gdbarch associated with the value. */
|
||
|
||
extern struct gdbarch *get_value_arch (const struct value *value);
|
||
|
||
/* This is being used to change the type of an existing value, that
|
||
code should instead be creating a new value with the changed type
|
||
(but possibly shared content). */
|
||
|
||
extern void deprecated_set_value_type (struct value *value,
|
||
struct type *type);
|
||
|
||
/* Only used for bitfields; number of bits contained in them. */
|
||
|
||
extern LONGEST value_bitsize (const struct value *);
|
||
extern void set_value_bitsize (struct value *, LONGEST bit);
|
||
|
||
/* Only used for bitfields; position of start of field. For
|
||
gdbarch_bits_big_endian=0 targets, it is the position of the LSB. For
|
||
gdbarch_bits_big_endian=1 targets, it is the position of the MSB. */
|
||
|
||
extern LONGEST value_bitpos (const struct value *);
|
||
extern void set_value_bitpos (struct value *, LONGEST bit);
|
||
|
||
/* Only used for bitfields; the containing value. This allows a
|
||
single read from the target when displaying multiple
|
||
bitfields. */
|
||
|
||
struct value *value_parent (const struct value *);
|
||
extern void set_value_parent (struct value *value, struct value *parent);
|
||
|
||
/* Describes offset of a value within lval of a structure in bytes.
|
||
If lval == lval_memory, this is an offset to the address. If lval
|
||
== lval_register, this is a further offset from location.address
|
||
within the registers structure. Note also the member
|
||
embedded_offset below. */
|
||
|
||
extern LONGEST value_offset (const struct value *);
|
||
extern void set_value_offset (struct value *, LONGEST offset);
|
||
|
||
/* The comment from "struct value" reads: ``Is it modifiable? Only
|
||
relevant if lval != not_lval.''. Shouldn't the value instead be
|
||
not_lval and be done with it? */
|
||
|
||
extern int deprecated_value_modifiable (const struct value *value);
|
||
|
||
/* If a value represents a C++ object, then the `type' field gives the
|
||
object's compile-time type. If the object actually belongs to some
|
||
class derived from `type', perhaps with other base classes and
|
||
additional members, then `type' is just a subobject of the real
|
||
thing, and the full object is probably larger than `type' would
|
||
suggest.
|
||
|
||
If `type' is a dynamic class (i.e. one with a vtable), then GDB can
|
||
actually determine the object's run-time type by looking at the
|
||
run-time type information in the vtable. When this information is
|
||
available, we may elect to read in the entire object, for several
|
||
reasons:
|
||
|
||
- When printing the value, the user would probably rather see the
|
||
full object, not just the limited portion apparent from the
|
||
compile-time type.
|
||
|
||
- If `type' has virtual base classes, then even printing `type'
|
||
alone may require reaching outside the `type' portion of the
|
||
object to wherever the virtual base class has been stored.
|
||
|
||
When we store the entire object, `enclosing_type' is the run-time
|
||
type -- the complete object -- and `embedded_offset' is the offset
|
||
of `type' within that larger type, in bytes. The value_contents()
|
||
macro takes `embedded_offset' into account, so most GDB code
|
||
continues to see the `type' portion of the value, just as the
|
||
inferior would.
|
||
|
||
If `type' is a pointer to an object, then `enclosing_type' is a
|
||
pointer to the object's run-time type, and `pointed_to_offset' is
|
||
the offset in bytes from the full object to the pointed-to object
|
||
-- that is, the value `embedded_offset' would have if we followed
|
||
the pointer and fetched the complete object. (I don't really see
|
||
the point. Why not just determine the run-time type when you
|
||
indirect, and avoid the special case? The contents don't matter
|
||
until you indirect anyway.)
|
||
|
||
If we're not doing anything fancy, `enclosing_type' is equal to
|
||
`type', and `embedded_offset' is zero, so everything works
|
||
normally. */
|
||
|
||
extern struct type *value_enclosing_type (const struct value *);
|
||
extern void set_value_enclosing_type (struct value *val,
|
||
struct type *new_type);
|
||
|
||
/* Returns value_type or value_enclosing_type depending on
|
||
value_print_options.objectprint.
|
||
|
||
If RESOLVE_SIMPLE_TYPES is 0 the enclosing type will be resolved
|
||
only for pointers and references, else it will be returned
|
||
for all the types (e.g. structures). This option is useful
|
||
to prevent retrieving enclosing type for the base classes fields.
|
||
|
||
REAL_TYPE_FOUND is used to inform whether the real type was found
|
||
(or just static type was used). The NULL may be passed if it is not
|
||
necessary. */
|
||
|
||
extern struct type *value_actual_type (struct value *value,
|
||
int resolve_simple_types,
|
||
int *real_type_found);
|
||
|
||
extern LONGEST value_pointed_to_offset (const struct value *value);
|
||
extern void set_value_pointed_to_offset (struct value *value, LONGEST val);
|
||
extern LONGEST value_embedded_offset (const struct value *value);
|
||
extern void set_value_embedded_offset (struct value *value, LONGEST val);
|
||
|
||
/* For lval_computed values, this structure holds functions used to
|
||
retrieve and set the value (or portions of the value).
|
||
|
||
For each function, 'V' is the 'this' pointer: an lval_funcs
|
||
function F may always assume that the V it receives is an
|
||
lval_computed value, and has F in the appropriate slot of its
|
||
lval_funcs structure. */
|
||
|
||
struct lval_funcs
|
||
{
|
||
/* Fill in VALUE's contents. This is used to "un-lazy" values. If
|
||
a problem arises in obtaining VALUE's bits, this function should
|
||
call 'error'. If it is NULL value_fetch_lazy on "un-lazy"
|
||
non-optimized-out value is an internal error. */
|
||
void (*read) (struct value *v);
|
||
|
||
/* Handle an assignment TOVAL = FROMVAL by writing the value of
|
||
FROMVAL to TOVAL's location. The contents of TOVAL have not yet
|
||
been updated. If a problem arises in doing so, this function
|
||
should call 'error'. If it is NULL such TOVAL assignment is an error as
|
||
TOVAL is not considered as an lvalue. */
|
||
void (*write) (struct value *toval, struct value *fromval);
|
||
|
||
/* If non-NULL, this is used to implement pointer indirection for
|
||
this value. This method may return NULL, in which case value_ind
|
||
will fall back to ordinary indirection. */
|
||
struct value *(*indirect) (struct value *value);
|
||
|
||
/* If non-NULL, this is used to implement reference resolving for
|
||
this value. This method may return NULL, in which case coerce_ref
|
||
will fall back to ordinary references resolving. */
|
||
struct value *(*coerce_ref) (const struct value *value);
|
||
|
||
/* If non-NULL, this is used to determine whether the indicated bits
|
||
of VALUE are a synthetic pointer. */
|
||
int (*check_synthetic_pointer) (const struct value *value,
|
||
LONGEST offset, int length);
|
||
|
||
/* Return a duplicate of VALUE's closure, for use in a new value.
|
||
This may simply return the same closure, if VALUE's is
|
||
reference-counted or statically allocated.
|
||
|
||
This may be NULL, in which case VALUE's closure is re-used in the
|
||
new value. */
|
||
void *(*copy_closure) (const struct value *v);
|
||
|
||
/* Drop VALUE's reference to its closure. Maybe this frees the
|
||
closure; maybe this decrements a reference count; maybe the
|
||
closure is statically allocated and this does nothing.
|
||
|
||
This may be NULL, in which case no action is taken to free
|
||
VALUE's closure. */
|
||
void (*free_closure) (struct value *v);
|
||
};
|
||
|
||
/* Create a computed lvalue, with type TYPE, function pointers FUNCS,
|
||
and closure CLOSURE. */
|
||
|
||
extern struct value *allocate_computed_value (struct type *type,
|
||
const struct lval_funcs *funcs,
|
||
void *closure);
|
||
|
||
/* Helper function to check the validity of some bits of a value.
|
||
|
||
If TYPE represents some aggregate type (e.g., a structure), return 1.
|
||
|
||
Otherwise, any of the bytes starting at OFFSET and extending for
|
||
TYPE_LENGTH(TYPE) bytes are invalid, print a message to STREAM and
|
||
return 0. The checking is done using FUNCS.
|
||
|
||
Otherwise, return 1. */
|
||
|
||
extern int valprint_check_validity (struct ui_file *stream, struct type *type,
|
||
LONGEST embedded_offset,
|
||
const struct value *val);
|
||
|
||
extern struct value *allocate_optimized_out_value (struct type *type);
|
||
|
||
/* If VALUE is lval_computed, return its lval_funcs structure. */
|
||
|
||
extern const struct lval_funcs *value_computed_funcs (const struct value *);
|
||
|
||
/* If VALUE is lval_computed, return its closure. The meaning of the
|
||
returned value depends on the functions VALUE uses. */
|
||
|
||
extern void *value_computed_closure (const struct value *value);
|
||
|
||
/* If zero, contents of this value are in the contents field. If
|
||
nonzero, contents are in inferior. If the lval field is lval_memory,
|
||
the contents are in inferior memory at location.address plus offset.
|
||
The lval field may also be lval_register.
|
||
|
||
WARNING: This field is used by the code which handles watchpoints
|
||
(see breakpoint.c) to decide whether a particular value can be
|
||
watched by hardware watchpoints. If the lazy flag is set for some
|
||
member of a value chain, it is assumed that this member of the
|
||
chain doesn't need to be watched as part of watching the value
|
||
itself. This is how GDB avoids watching the entire struct or array
|
||
when the user wants to watch a single struct member or array
|
||
element. If you ever change the way lazy flag is set and reset, be
|
||
sure to consider this use as well! */
|
||
|
||
extern int value_lazy (const struct value *);
|
||
extern void set_value_lazy (struct value *value, int val);
|
||
|
||
extern int value_stack (const struct value *);
|
||
extern void set_value_stack (struct value *value, int val);
|
||
|
||
/* Throw an error complaining that the value has been optimized
|
||
out. */
|
||
|
||
extern void error_value_optimized_out (void);
|
||
|
||
/* value_contents() and value_contents_raw() both return the address
|
||
of the gdb buffer used to hold a copy of the contents of the lval.
|
||
value_contents() is used when the contents of the buffer are needed
|
||
-- it uses value_fetch_lazy() to load the buffer from the process
|
||
being debugged if it hasn't already been loaded
|
||
(value_contents_writeable() is used when a writeable but fetched
|
||
buffer is required).. value_contents_raw() is used when data is
|
||
being stored into the buffer, or when it is certain that the
|
||
contents of the buffer are valid.
|
||
|
||
Note: The contents pointer is adjusted by the offset required to
|
||
get to the real subobject, if the value happens to represent
|
||
something embedded in a larger run-time object. */
|
||
|
||
extern gdb_byte *value_contents_raw (struct value *);
|
||
|
||
/* Actual contents of the value. For use of this value; setting it
|
||
uses the stuff above. Not valid if lazy is nonzero. Target
|
||
byte-order. We force it to be aligned properly for any possible
|
||
value. Note that a value therefore extends beyond what is
|
||
declared here. */
|
||
|
||
extern const gdb_byte *value_contents (struct value *);
|
||
extern gdb_byte *value_contents_writeable (struct value *);
|
||
|
||
/* The ALL variants of the above two macros do not adjust the returned
|
||
pointer by the embedded_offset value. */
|
||
|
||
extern gdb_byte *value_contents_all_raw (struct value *);
|
||
extern const gdb_byte *value_contents_all (struct value *);
|
||
|
||
/* Like value_contents_all, but does not require that the returned
|
||
bits be valid. This should only be used in situations where you
|
||
plan to check the validity manually. */
|
||
extern const gdb_byte *value_contents_for_printing (struct value *value);
|
||
|
||
/* Like value_contents_for_printing, but accepts a constant value
|
||
pointer. Unlike value_contents_for_printing however, the pointed
|
||
value must _not_ be lazy. */
|
||
extern const gdb_byte *
|
||
value_contents_for_printing_const (const struct value *value);
|
||
|
||
extern void value_fetch_lazy (struct value *val);
|
||
|
||
/* If nonzero, this is the value of a variable which does not actually
|
||
exist in the program, at least partially. If the value is lazy,
|
||
this may fetch it now. */
|
||
extern int value_optimized_out (struct value *value);
|
||
|
||
/* Given a value, return true if any of the contents bits starting at
|
||
OFFSET and extending for LENGTH bits is optimized out, false
|
||
otherwise. */
|
||
|
||
extern int value_bits_any_optimized_out (const struct value *value,
|
||
int bit_offset, int bit_length);
|
||
|
||
/* Like value_optimized_out, but return true iff the whole value is
|
||
optimized out. */
|
||
extern int value_entirely_optimized_out (struct value *value);
|
||
|
||
/* Mark VALUE's content bytes starting at OFFSET and extending for
|
||
LENGTH bytes as optimized out. */
|
||
|
||
extern void mark_value_bytes_optimized_out (struct value *value,
|
||
int offset, int length);
|
||
|
||
/* Mark VALUE's content bits starting at OFFSET and extending for
|
||
LENGTH bits as optimized out. */
|
||
|
||
extern void mark_value_bits_optimized_out (struct value *value,
|
||
LONGEST offset, LONGEST length);
|
||
|
||
/* Set or return field indicating whether a variable is initialized or
|
||
not, based on debugging information supplied by the compiler.
|
||
1 = initialized; 0 = uninitialized. */
|
||
extern int value_initialized (const struct value *);
|
||
extern void set_value_initialized (struct value *, int);
|
||
|
||
/* Set COMPONENT's location as appropriate for a component of WHOLE
|
||
--- regardless of what kind of lvalue WHOLE is. */
|
||
extern void set_value_component_location (struct value *component,
|
||
const struct value *whole);
|
||
|
||
/* While the following fields are per- VALUE .CONTENT .PIECE (i.e., a
|
||
single value might have multiple LVALs), this hacked interface is
|
||
limited to just the first PIECE. Expect further change. */
|
||
/* Type of value; either not an lval, or one of the various different
|
||
possible kinds of lval. */
|
||
extern enum lval_type *deprecated_value_lval_hack (struct value *);
|
||
#define VALUE_LVAL(val) (*deprecated_value_lval_hack (val))
|
||
|
||
/* Like VALUE_LVAL, except the parameter can be const. */
|
||
extern enum lval_type value_lval_const (const struct value *value);
|
||
|
||
/* If lval == lval_memory, return the address in the inferior. If
|
||
lval == lval_register, return the byte offset into the registers
|
||
structure. Otherwise, return 0. The returned address
|
||
includes the offset, if any. */
|
||
extern CORE_ADDR value_address (const struct value *);
|
||
|
||
/* Like value_address, except the result does not include value's
|
||
offset. */
|
||
extern CORE_ADDR value_raw_address (const struct value *);
|
||
|
||
/* Set the address of a value. */
|
||
extern void set_value_address (struct value *, CORE_ADDR);
|
||
|
||
/* Pointer to internal variable. */
|
||
extern struct internalvar **deprecated_value_internalvar_hack (struct value *);
|
||
#define VALUE_INTERNALVAR(val) (*deprecated_value_internalvar_hack (val))
|
||
|
||
/* Frame ID of "next" frame to which a register value is relative. A
|
||
register value is indicated by VALUE_LVAL being set to lval_register.
|
||
So, if the register value is found relative to frame F, then the
|
||
frame id of F->next will be stored in VALUE_NEXT_FRAME_ID. */
|
||
extern struct frame_id *deprecated_value_next_frame_id_hack (struct value *);
|
||
#define VALUE_NEXT_FRAME_ID(val) (*deprecated_value_next_frame_id_hack (val))
|
||
|
||
/* Frame ID of frame to which a register value is relative. This is
|
||
similar to VALUE_NEXT_FRAME_ID, above, but may not be assigned to.
|
||
Note that VALUE_FRAME_ID effectively undoes the "next" operation
|
||
that was performed during the assignment to VALUE_NEXT_FRAME_ID. */
|
||
#define VALUE_FRAME_ID(val) (get_prev_frame_id_by_id (VALUE_NEXT_FRAME_ID (val)))
|
||
|
||
/* Register number if the value is from a register. */
|
||
extern int *deprecated_value_regnum_hack (struct value *);
|
||
#define VALUE_REGNUM(val) (*deprecated_value_regnum_hack (val))
|
||
|
||
/* Return value after lval_funcs->coerce_ref (after check_typedef). Return
|
||
NULL if lval_funcs->coerce_ref is not applicable for whatever reason. */
|
||
|
||
extern struct value *coerce_ref_if_computed (const struct value *arg);
|
||
|
||
/* Setup a new value type and enclosing value type for dereferenced value VALUE.
|
||
ENC_TYPE is the new enclosing type that should be set. ORIGINAL_TYPE and
|
||
ORIGINAL_VAL are the type and value of the original reference or pointer.
|
||
|
||
Note, that VALUE is modified by this function.
|
||
|
||
It is a common implementation for coerce_ref and value_ind. */
|
||
|
||
extern struct value * readjust_indirect_value_type (struct value *value,
|
||
struct type *enc_type,
|
||
const struct type *original_type,
|
||
const struct value *original_val);
|
||
|
||
/* Convert a REF to the object referenced. */
|
||
|
||
extern struct value *coerce_ref (struct value *value);
|
||
|
||
/* If ARG is an array, convert it to a pointer.
|
||
If ARG is a function, convert it to a function pointer.
|
||
|
||
References are dereferenced. */
|
||
|
||
extern struct value *coerce_array (struct value *value);
|
||
|
||
/* Given a value, determine whether the bits starting at OFFSET and
|
||
extending for LENGTH bits are a synthetic pointer. */
|
||
|
||
extern int value_bits_synthetic_pointer (const struct value *value,
|
||
LONGEST offset, LONGEST length);
|
||
|
||
/* Given a value, determine whether the contents bytes starting at
|
||
OFFSET and extending for LENGTH bytes are available. This returns
|
||
nonzero if all bytes in the given range are available, zero if any
|
||
byte is unavailable. */
|
||
|
||
extern int value_bytes_available (const struct value *value,
|
||
LONGEST offset, LONGEST length);
|
||
|
||
/* Given a value, determine whether the contents bits starting at
|
||
OFFSET and extending for LENGTH bits are available. This returns
|
||
nonzero if all bits in the given range are available, zero if any
|
||
bit is unavailable. */
|
||
|
||
extern int value_bits_available (const struct value *value,
|
||
LONGEST offset, LONGEST length);
|
||
|
||
/* Like value_bytes_available, but return false if any byte in the
|
||
whole object is unavailable. */
|
||
extern int value_entirely_available (struct value *value);
|
||
|
||
/* Like value_entirely_available, but return false if any byte in the
|
||
whole object is available. */
|
||
extern int value_entirely_unavailable (struct value *value);
|
||
|
||
/* Mark VALUE's content bytes starting at OFFSET and extending for
|
||
LENGTH bytes as unavailable. */
|
||
|
||
extern void mark_value_bytes_unavailable (struct value *value,
|
||
LONGEST offset, LONGEST length);
|
||
|
||
/* Mark VALUE's content bits starting at OFFSET and extending for
|
||
LENGTH bits as unavailable. */
|
||
|
||
extern void mark_value_bits_unavailable (struct value *value,
|
||
LONGEST offset, LONGEST length);
|
||
|
||
/* Compare LENGTH bytes of VAL1's contents starting at OFFSET1 with
|
||
LENGTH bytes of VAL2's contents starting at OFFSET2.
|
||
|
||
Note that "contents" refers to the whole value's contents
|
||
(value_contents_all), without any embedded offset adjustment. For
|
||
example, to compare a complete object value with itself, including
|
||
its enclosing type chunk, you'd do:
|
||
|
||
int len = TYPE_LENGTH (check_typedef (value_enclosing_type (val)));
|
||
value_contents_eq (val, 0, val, 0, len);
|
||
|
||
Returns true iff the set of available/valid contents match.
|
||
|
||
Optimized-out contents are equal to optimized-out contents, and are
|
||
not equal to non-optimized-out contents.
|
||
|
||
Unavailable contente are equal to unavailable contents, and are not
|
||
equal to non-unavailable contents.
|
||
|
||
For example, if 'x's represent an unavailable byte, and 'V' and 'Z'
|
||
represent different available/valid bytes, in a value with length
|
||
16:
|
||
|
||
offset: 0 4 8 12 16
|
||
contents: xxxxVVVVxxxxVVZZ
|
||
|
||
then:
|
||
|
||
value_contents_eq(val, 0, val, 8, 6) => true
|
||
value_contents_eq(val, 0, val, 4, 4) => false
|
||
value_contents_eq(val, 0, val, 8, 8) => false
|
||
value_contents_eq(val, 4, val, 12, 2) => true
|
||
value_contents_eq(val, 4, val, 12, 4) => true
|
||
value_contents_eq(val, 3, val, 4, 4) => true
|
||
|
||
If 'x's represent an unavailable byte, 'o' represents an optimized
|
||
out byte, in a value with length 8:
|
||
|
||
offset: 0 4 8
|
||
contents: xxxxoooo
|
||
|
||
then:
|
||
|
||
value_contents_eq(val, 0, val, 2, 2) => true
|
||
value_contents_eq(val, 4, val, 6, 2) => true
|
||
value_contents_eq(val, 0, val, 4, 4) => true
|
||
|
||
We only know whether a value chunk is unavailable or optimized out
|
||
if we've tried to read it. As this routine is used by printing
|
||
routines, which may be printing values in the value history, long
|
||
after the inferior is gone, it works with const values. Therefore,
|
||
this routine must not be called with lazy values. */
|
||
|
||
extern bool value_contents_eq (const struct value *val1, LONGEST offset1,
|
||
const struct value *val2, LONGEST offset2,
|
||
LONGEST length);
|
||
|
||
/* Read LENGTH addressable memory units starting at MEMADDR into BUFFER,
|
||
which is (or will be copied to) VAL's contents buffer offset by
|
||
BIT_OFFSET bits. Marks value contents ranges as unavailable if
|
||
the corresponding memory is likewise unavailable. STACK indicates
|
||
whether the memory is known to be stack memory. */
|
||
|
||
extern void read_value_memory (struct value *val, LONGEST bit_offset,
|
||
int stack, CORE_ADDR memaddr,
|
||
gdb_byte *buffer, size_t length);
|
||
|
||
/* Cast SCALAR_VALUE to the element type of VECTOR_TYPE, then replicate
|
||
into each element of a new vector value with VECTOR_TYPE. */
|
||
|
||
struct value *value_vector_widen (struct value *scalar_value,
|
||
struct type *vector_type);
|
||
|
||
|
||
|
||
#include "symtab.h"
|
||
#include "gdbtypes.h"
|
||
#include "expression.h"
|
||
|
||
struct frame_info;
|
||
struct fn_field;
|
||
|
||
extern int print_address_demangle (const struct value_print_options *,
|
||
struct gdbarch *, CORE_ADDR,
|
||
struct ui_file *, int);
|
||
|
||
/* Returns true if VAL is of floating-point type. In addition,
|
||
throws an error if the value is an invalid floating-point value. */
|
||
extern bool is_floating_value (struct value *val);
|
||
|
||
extern LONGEST value_as_long (struct value *val);
|
||
extern CORE_ADDR value_as_address (struct value *val);
|
||
|
||
extern LONGEST unpack_long (struct type *type, const gdb_byte *valaddr);
|
||
extern CORE_ADDR unpack_pointer (struct type *type, const gdb_byte *valaddr);
|
||
|
||
extern LONGEST unpack_field_as_long (struct type *type,
|
||
const gdb_byte *valaddr,
|
||
int fieldno);
|
||
extern int unpack_value_field_as_long (struct type *type, const gdb_byte *valaddr,
|
||
LONGEST embedded_offset, int fieldno,
|
||
const struct value *val, LONGEST *result);
|
||
|
||
extern void unpack_value_bitfield (struct value *dest_val,
|
||
LONGEST bitpos, LONGEST bitsize,
|
||
const gdb_byte *valaddr,
|
||
LONGEST embedded_offset,
|
||
const struct value *val);
|
||
|
||
extern struct value *value_field_bitfield (struct type *type, int fieldno,
|
||
const gdb_byte *valaddr,
|
||
LONGEST embedded_offset,
|
||
const struct value *val);
|
||
|
||
extern void pack_long (gdb_byte *buf, struct type *type, LONGEST num);
|
||
|
||
extern struct value *value_from_longest (struct type *type, LONGEST num);
|
||
extern struct value *value_from_ulongest (struct type *type, ULONGEST num);
|
||
extern struct value *value_from_pointer (struct type *type, CORE_ADDR addr);
|
||
extern struct value *value_from_history_ref (const char *, const char **);
|
||
extern struct value *value_from_component (struct value *, struct type *,
|
||
LONGEST);
|
||
|
||
extern struct value *value_at (struct type *type, CORE_ADDR addr);
|
||
extern struct value *value_at_lazy (struct type *type, CORE_ADDR addr);
|
||
|
||
extern struct value *value_from_contents_and_address_unresolved
|
||
(struct type *, const gdb_byte *, CORE_ADDR);
|
||
extern struct value *value_from_contents_and_address (struct type *,
|
||
const gdb_byte *,
|
||
CORE_ADDR);
|
||
extern struct value *value_from_contents (struct type *, const gdb_byte *);
|
||
|
||
extern struct value *default_value_from_register (struct gdbarch *gdbarch,
|
||
struct type *type,
|
||
int regnum,
|
||
struct frame_id frame_id);
|
||
|
||
extern void read_frame_register_value (struct value *value,
|
||
struct frame_info *frame);
|
||
|
||
extern struct value *value_from_register (struct type *type, int regnum,
|
||
struct frame_info *frame);
|
||
|
||
extern CORE_ADDR address_from_register (int regnum,
|
||
struct frame_info *frame);
|
||
|
||
extern struct value *value_of_variable (struct symbol *var,
|
||
const struct block *b);
|
||
|
||
extern struct value *address_of_variable (struct symbol *var,
|
||
const struct block *b);
|
||
|
||
extern struct value *value_of_register (int regnum, struct frame_info *frame);
|
||
|
||
struct value *value_of_register_lazy (struct frame_info *frame, int regnum);
|
||
|
||
/* Return the symbol's reading requirement. */
|
||
|
||
extern enum symbol_needs_kind symbol_read_needs (struct symbol *);
|
||
|
||
/* Return true if the symbol needs a frame. This is a wrapper for
|
||
symbol_read_needs that simply checks for SYMBOL_NEEDS_FRAME. */
|
||
|
||
extern int symbol_read_needs_frame (struct symbol *);
|
||
|
||
extern struct value *read_var_value (struct symbol *var,
|
||
const struct block *var_block,
|
||
struct frame_info *frame);
|
||
|
||
extern struct value *default_read_var_value (struct symbol *var,
|
||
const struct block *var_block,
|
||
struct frame_info *frame);
|
||
|
||
extern struct value *allocate_value (struct type *type);
|
||
extern struct value *allocate_value_lazy (struct type *type);
|
||
extern void value_contents_copy (struct value *dst, LONGEST dst_offset,
|
||
struct value *src, LONGEST src_offset,
|
||
LONGEST length);
|
||
extern void value_contents_copy_raw (struct value *dst, LONGEST dst_offset,
|
||
struct value *src, LONGEST src_offset,
|
||
LONGEST length);
|
||
|
||
extern struct value *allocate_repeat_value (struct type *type, int count);
|
||
|
||
extern struct value *value_mark (void);
|
||
|
||
extern void value_free_to_mark (const struct value *mark);
|
||
|
||
/* A helper class that uses value_mark at construction time and calls
|
||
value_free_to_mark in the destructor. This is used to clear out
|
||
temporary values created during the lifetime of this object. */
|
||
class scoped_value_mark
|
||
{
|
||
public:
|
||
|
||
scoped_value_mark ()
|
||
: m_value (value_mark ())
|
||
{
|
||
}
|
||
|
||
~scoped_value_mark ()
|
||
{
|
||
free_to_mark ();
|
||
}
|
||
|
||
scoped_value_mark (scoped_value_mark &&other) = default;
|
||
|
||
DISABLE_COPY_AND_ASSIGN (scoped_value_mark);
|
||
|
||
/* Free the values currently on the value stack. */
|
||
void free_to_mark ()
|
||
{
|
||
if (m_value != NULL)
|
||
{
|
||
value_free_to_mark (m_value);
|
||
m_value = NULL;
|
||
}
|
||
}
|
||
|
||
private:
|
||
|
||
const struct value *m_value;
|
||
};
|
||
|
||
extern struct value *value_cstring (const char *ptr, ssize_t len,
|
||
struct type *char_type);
|
||
extern struct value *value_string (const char *ptr, ssize_t len,
|
||
struct type *char_type);
|
||
|
||
extern struct value *value_array (int lowbound, int highbound,
|
||
struct value **elemvec);
|
||
|
||
extern struct value *value_concat (struct value *arg1, struct value *arg2);
|
||
|
||
extern struct value *value_binop (struct value *arg1, struct value *arg2,
|
||
enum exp_opcode op);
|
||
|
||
extern struct value *value_ptradd (struct value *arg1, LONGEST arg2);
|
||
|
||
extern LONGEST value_ptrdiff (struct value *arg1, struct value *arg2);
|
||
|
||
extern int value_must_coerce_to_target (struct value *arg1);
|
||
|
||
extern struct value *value_coerce_to_target (struct value *arg1);
|
||
|
||
extern struct value *value_coerce_array (struct value *arg1);
|
||
|
||
extern struct value *value_coerce_function (struct value *arg1);
|
||
|
||
extern struct value *value_ind (struct value *arg1);
|
||
|
||
extern struct value *value_addr (struct value *arg1);
|
||
|
||
extern struct value *value_ref (struct value *arg1, enum type_code refcode);
|
||
|
||
extern struct value *value_assign (struct value *toval,
|
||
struct value *fromval);
|
||
|
||
extern struct value *value_pos (struct value *arg1);
|
||
|
||
extern struct value *value_neg (struct value *arg1);
|
||
|
||
extern struct value *value_complement (struct value *arg1);
|
||
|
||
extern struct value *value_struct_elt (struct value **argp,
|
||
struct value **args,
|
||
const char *name, int *static_memfuncp,
|
||
const char *err);
|
||
|
||
extern struct value *value_struct_elt_bitpos (struct value **argp,
|
||
int bitpos,
|
||
struct type *field_type,
|
||
const char *err);
|
||
|
||
extern struct value *value_aggregate_elt (struct type *curtype,
|
||
const char *name,
|
||
struct type *expect_type,
|
||
int want_address,
|
||
enum noside noside);
|
||
|
||
extern struct value *value_static_field (struct type *type, int fieldno);
|
||
|
||
enum oload_search_type { NON_METHOD, METHOD, BOTH };
|
||
|
||
extern int find_overload_match (struct value **args, int nargs,
|
||
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,
|
||
enum noside noside);
|
||
|
||
extern struct value *value_field (struct value *arg1, int fieldno);
|
||
|
||
extern struct value *value_primitive_field (struct value *arg1, LONGEST offset,
|
||
int fieldno,
|
||
struct type *arg_type);
|
||
|
||
|
||
extern struct type *value_rtti_indirect_type (struct value *, int *, LONGEST *,
|
||
int *);
|
||
|
||
extern struct value *value_full_object (struct value *, struct type *, int,
|
||
int, int);
|
||
|
||
extern struct value *value_cast_pointers (struct type *, struct value *, int);
|
||
|
||
extern struct value *value_cast (struct type *type, struct value *arg2);
|
||
|
||
extern struct value *value_reinterpret_cast (struct type *type,
|
||
struct value *arg);
|
||
|
||
extern struct value *value_dynamic_cast (struct type *type, struct value *arg);
|
||
|
||
extern struct value *value_zero (struct type *type, enum lval_type lv);
|
||
|
||
extern struct value *value_one (struct type *type);
|
||
|
||
extern struct value *value_repeat (struct value *arg1, int count);
|
||
|
||
extern struct value *value_subscript (struct value *array, LONGEST index);
|
||
|
||
extern struct value *value_bitstring_subscript (struct type *type,
|
||
struct value *bitstring,
|
||
LONGEST index);
|
||
|
||
extern struct value *register_value_being_returned (struct type *valtype,
|
||
struct regcache *retbuf);
|
||
|
||
extern int value_in (struct value *element, struct value *set);
|
||
|
||
extern int value_bit_index (struct type *type, const gdb_byte *addr,
|
||
int index);
|
||
|
||
extern enum return_value_convention
|
||
struct_return_convention (struct gdbarch *gdbarch, struct value *function,
|
||
struct type *value_type);
|
||
|
||
extern int using_struct_return (struct gdbarch *gdbarch,
|
||
struct value *function,
|
||
struct type *value_type);
|
||
|
||
extern struct value *evaluate_expression (struct expression *exp);
|
||
|
||
extern struct value *evaluate_type (struct expression *exp);
|
||
|
||
extern struct value *evaluate_subexp (struct type *expect_type,
|
||
struct expression *exp,
|
||
int *pos, enum noside noside);
|
||
|
||
extern struct value *evaluate_subexpression_type (struct expression *exp,
|
||
int subexp);
|
||
|
||
extern value *evaluate_var_value (enum noside noside, const block *blk,
|
||
symbol *var);
|
||
|
||
extern value *evaluate_var_msym_value (enum noside noside,
|
||
struct objfile *objfile,
|
||
minimal_symbol *msymbol);
|
||
|
||
extern value *eval_skip_value (expression *exp);
|
||
|
||
extern void fetch_subexp_value (struct expression *exp, int *pc,
|
||
struct value **valp, struct value **resultp,
|
||
struct value **val_chain,
|
||
int preserve_errors);
|
||
|
||
extern const char *extract_field_op (struct expression *exp, int *subexp);
|
||
|
||
extern struct value *evaluate_subexp_with_coercion (struct expression *,
|
||
int *, enum noside);
|
||
|
||
extern struct value *parse_and_eval (const char *exp);
|
||
|
||
extern struct value *parse_to_comma_and_eval (const char **expp);
|
||
|
||
extern struct type *parse_and_eval_type (char *p, int length);
|
||
|
||
extern CORE_ADDR parse_and_eval_address (const char *exp);
|
||
|
||
extern LONGEST parse_and_eval_long (const char *exp);
|
||
|
||
extern void unop_promote (const struct language_defn *language,
|
||
struct gdbarch *gdbarch,
|
||
struct value **arg1);
|
||
|
||
extern void binop_promote (const struct language_defn *language,
|
||
struct gdbarch *gdbarch,
|
||
struct value **arg1, struct value **arg2);
|
||
|
||
extern struct value *access_value_history (int num);
|
||
|
||
extern struct value *value_of_internalvar (struct gdbarch *gdbarch,
|
||
struct internalvar *var);
|
||
|
||
extern int get_internalvar_integer (struct internalvar *var, LONGEST *l);
|
||
|
||
extern void set_internalvar (struct internalvar *var, struct value *val);
|
||
|
||
extern void set_internalvar_integer (struct internalvar *var, LONGEST l);
|
||
|
||
extern void set_internalvar_string (struct internalvar *var,
|
||
const char *string);
|
||
|
||
extern void clear_internalvar (struct internalvar *var);
|
||
|
||
extern void set_internalvar_component (struct internalvar *var,
|
||
LONGEST offset,
|
||
LONGEST bitpos, LONGEST bitsize,
|
||
struct value *newvalue);
|
||
|
||
extern struct internalvar *lookup_only_internalvar (const char *name);
|
||
|
||
extern struct internalvar *create_internalvar (const char *name);
|
||
|
||
extern void complete_internalvar (completion_tracker &tracker,
|
||
const char *name);
|
||
|
||
/* An internalvar can be dynamically computed by supplying a vector of
|
||
function pointers to perform various operations. */
|
||
|
||
struct internalvar_funcs
|
||
{
|
||
/* Compute the value of the variable. The DATA argument passed to
|
||
the function is the same argument that was passed to
|
||
`create_internalvar_type_lazy'. */
|
||
|
||
struct value *(*make_value) (struct gdbarch *arch,
|
||
struct internalvar *var,
|
||
void *data);
|
||
|
||
/* Update the agent expression EXPR with bytecode to compute the
|
||
value. VALUE is the agent value we are updating. The DATA
|
||
argument passed to this function is the same argument that was
|
||
passed to `create_internalvar_type_lazy'. If this pointer is
|
||
NULL, then the internalvar cannot be compiled to an agent
|
||
expression. */
|
||
|
||
void (*compile_to_ax) (struct internalvar *var,
|
||
struct agent_expr *expr,
|
||
struct axs_value *value,
|
||
void *data);
|
||
|
||
/* If non-NULL, this is called to destroy DATA. The DATA argument
|
||
passed to this function is the same argument that was passed to
|
||
`create_internalvar_type_lazy'. */
|
||
|
||
void (*destroy) (void *data);
|
||
};
|
||
|
||
extern struct internalvar *create_internalvar_type_lazy (const char *name,
|
||
const struct internalvar_funcs *funcs,
|
||
void *data);
|
||
|
||
/* Compile an internal variable to an agent expression. VAR is the
|
||
variable to compile; EXPR and VALUE are the agent expression we are
|
||
updating. This will return 0 if there is no known way to compile
|
||
VAR, and 1 if VAR was successfully compiled. It may also throw an
|
||
exception on error. */
|
||
|
||
extern int compile_internalvar_to_ax (struct internalvar *var,
|
||
struct agent_expr *expr,
|
||
struct axs_value *value);
|
||
|
||
extern struct internalvar *lookup_internalvar (const char *name);
|
||
|
||
extern int value_equal (struct value *arg1, struct value *arg2);
|
||
|
||
extern int value_equal_contents (struct value *arg1, struct value *arg2);
|
||
|
||
extern int value_less (struct value *arg1, struct value *arg2);
|
||
|
||
extern int value_logical_not (struct value *arg1);
|
||
|
||
/* C++ */
|
||
|
||
extern struct value *value_of_this (const struct language_defn *lang);
|
||
|
||
extern struct value *value_of_this_silent (const struct language_defn *lang);
|
||
|
||
extern struct value *value_x_binop (struct value *arg1, struct value *arg2,
|
||
enum exp_opcode op,
|
||
enum exp_opcode otherop,
|
||
enum noside noside);
|
||
|
||
extern struct value *value_x_unop (struct value *arg1, enum exp_opcode op,
|
||
enum noside noside);
|
||
|
||
extern struct value *value_fn_field (struct value **arg1p, struct fn_field *f,
|
||
int j, struct type *type, LONGEST offset);
|
||
|
||
extern int binop_types_user_defined_p (enum exp_opcode op,
|
||
struct type *type1,
|
||
struct type *type2);
|
||
|
||
extern int binop_user_defined_p (enum exp_opcode op, struct value *arg1,
|
||
struct value *arg2);
|
||
|
||
extern int unop_user_defined_p (enum exp_opcode op, struct value *arg1);
|
||
|
||
extern int destructor_name_p (const char *name, struct type *type);
|
||
|
||
extern void value_incref (struct value *val);
|
||
|
||
extern void value_free (struct value *val);
|
||
|
||
/* A free policy class to interface std::unique_ptr with
|
||
value_free. */
|
||
|
||
struct value_deleter
|
||
{
|
||
void operator() (struct value *value) const
|
||
{
|
||
value_free (value);
|
||
}
|
||
};
|
||
|
||
/* A unique pointer to a struct value. */
|
||
|
||
typedef std::unique_ptr<struct value, value_deleter> gdb_value_up;
|
||
|
||
extern void free_all_values (void);
|
||
|
||
extern void free_value_chain (struct value *v);
|
||
|
||
extern void release_value (struct value *val);
|
||
|
||
extern void release_value_or_incref (struct value *val);
|
||
|
||
extern int record_latest_value (struct value *val);
|
||
|
||
extern void modify_field (struct type *type, gdb_byte *addr,
|
||
LONGEST fieldval, LONGEST bitpos, LONGEST bitsize);
|
||
|
||
extern void type_print (struct type *type, const char *varstring,
|
||
struct ui_file *stream, int show);
|
||
|
||
extern std::string type_to_string (struct type *type);
|
||
|
||
extern gdb_byte *baseclass_addr (struct type *type, int index,
|
||
gdb_byte *valaddr,
|
||
struct value **valuep, int *errp);
|
||
|
||
extern void print_longest (struct ui_file *stream, int format,
|
||
int use_local, LONGEST val);
|
||
|
||
extern void print_floating (const gdb_byte *valaddr, struct type *type,
|
||
struct ui_file *stream);
|
||
|
||
extern void value_print (struct value *val, struct ui_file *stream,
|
||
const struct value_print_options *options);
|
||
|
||
extern void value_print_array_elements (struct value *val,
|
||
struct ui_file *stream, int format,
|
||
enum val_prettyformat pretty);
|
||
|
||
extern struct value *value_release_to_mark (const struct value *mark);
|
||
|
||
extern void val_print (struct type *type,
|
||
LONGEST embedded_offset, CORE_ADDR address,
|
||
struct ui_file *stream, int recurse,
|
||
struct value *val,
|
||
const struct value_print_options *options,
|
||
const struct language_defn *language);
|
||
|
||
extern void common_val_print (struct value *val,
|
||
struct ui_file *stream, int recurse,
|
||
const struct value_print_options *options,
|
||
const struct language_defn *language);
|
||
|
||
extern int val_print_string (struct type *elttype, const char *encoding,
|
||
CORE_ADDR addr, int len,
|
||
struct ui_file *stream,
|
||
const struct value_print_options *options);
|
||
|
||
extern void print_variable_and_value (const char *name,
|
||
struct symbol *var,
|
||
struct frame_info *frame,
|
||
struct ui_file *stream,
|
||
int indent);
|
||
|
||
extern void typedef_print (struct type *type, struct symbol *news,
|
||
struct ui_file *stream);
|
||
|
||
extern char *internalvar_name (const struct internalvar *var);
|
||
|
||
extern void preserve_values (struct objfile *);
|
||
|
||
/* From values.c */
|
||
|
||
extern struct value *value_copy (struct value *);
|
||
|
||
extern struct value *value_non_lval (struct value *);
|
||
|
||
extern void value_force_lval (struct value *, CORE_ADDR);
|
||
|
||
extern struct value *make_cv_value (int, int, struct value *);
|
||
|
||
extern void preserve_one_value (struct value *, struct objfile *, htab_t);
|
||
|
||
/* From valops.c */
|
||
|
||
extern struct value *varying_to_slice (struct value *);
|
||
|
||
extern struct value *value_slice (struct value *, int, int);
|
||
|
||
extern struct value *value_literal_complex (struct value *, struct value *,
|
||
struct type *);
|
||
|
||
extern struct value *find_function_in_inferior (const char *,
|
||
struct objfile **);
|
||
|
||
extern struct value *value_allocate_space_in_inferior (int);
|
||
|
||
extern struct value *value_subscripted_rvalue (struct value *array,
|
||
LONGEST index, int lowerbound);
|
||
|
||
/* User function handler. */
|
||
|
||
typedef struct value *(*internal_function_fn) (struct gdbarch *gdbarch,
|
||
const struct language_defn *language,
|
||
void *cookie,
|
||
int argc,
|
||
struct value **argv);
|
||
|
||
void add_internal_function (const char *name, const char *doc,
|
||
internal_function_fn handler,
|
||
void *cookie);
|
||
|
||
struct value *call_internal_function (struct gdbarch *gdbarch,
|
||
const struct language_defn *language,
|
||
struct value *function,
|
||
int argc, struct value **argv);
|
||
|
||
char *value_internal_function_name (struct value *);
|
||
|
||
/* Build a value wrapping and representing WORKER. The value takes ownership
|
||
of the xmethod_worker object. */
|
||
|
||
extern struct value *value_from_xmethod (xmethod_worker_up &&worker);
|
||
|
||
extern struct type *result_type_of_xmethod (struct value *method,
|
||
int argc, struct value **argv);
|
||
|
||
extern struct value *call_xmethod (struct value *method,
|
||
int argc, struct value **argv);
|
||
|
||
/* Given a discriminated union type and some corresponding value
|
||
contents, this will return the field index of the currently active
|
||
variant. This will throw an exception if no active variant can be
|
||
found. */
|
||
|
||
extern int value_union_variant (struct type *union_type,
|
||
const gdb_byte *contents);
|
||
|
||
#endif /* !defined (VALUE_H) */
|