/* Definitions for values of C expressions, for GDB.
- Copyright (C) 1986-2016 Free Software Foundation, Inc.
+ Copyright (C) 1986-2020 Free Software Foundation, Inc.
This file is part of GDB.
#if !defined (VALUE_H)
#define VALUE_H 1
-#include "doublest.h"
#include "frame.h" /* For struct frame_id. */
+#include "extension.h"
+#include "gdbsupport/gdb_ref_ptr.h"
struct block;
struct expression;
struct ui_file;
struct language_defn;
struct value_print_options;
-struct xmethod_worker;
/* Values can be partially 'optimized out' and/or 'unavailable'.
These are distinct states and have different string representations
value_contents_eq for more info.
*/
+extern bool overload_resolution;
+
/* 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
struct value;
+/* Increase VAL's reference count. */
+
+extern void value_incref (struct value *val);
+
+/* Decrease VAL's reference count. When the reference count drops to
+ 0, VAL will be freed. */
+
+extern void value_decref (struct value *val);
+
+/* A policy class to interface gdb::ref_ptr with struct value. */
+
+struct value_ref_policy
+{
+ static void incref (struct value *ptr)
+ {
+ value_incref (ptr);
+ }
+
+ static void decref (struct value *ptr)
+ {
+ value_decref (ptr);
+ }
+};
+
+/* A gdb:;ref_ptr pointer to a struct value. */
+
+typedef gdb::ref_ptr<struct value, value_ref_policy> value_ref_ptr;
+
/* 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
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. */
+ little-endian targets, it is the position of the LSB. For
+ big-endian targets, it is the position of the MSB. */
extern LONGEST value_bitpos (const struct value *);
extern void set_value_bitpos (struct value *, LONGEST bit);
extern struct internalvar **deprecated_value_internalvar_hack (struct value *);
#define VALUE_INTERNALVAR(val) (*deprecated_value_internalvar_hack (val))
-/* Frame register value is relative to. This will be described in the
- lval enum above as "lval_register". */
-extern struct frame_id *deprecated_value_frame_id_hack (struct value *);
-#define VALUE_FRAME_ID(val) (*deprecated_value_frame_id_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 short *deprecated_value_regnum_hack (struct value *);
+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
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
+ Unavailable contents 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'
then:
- value_contents_eq(val, 0, val, 8, 6) => 1
- value_contents_eq(val, 0, val, 4, 4) => 0
- value_contents_eq(val, 0, val, 8, 8) => 0
- value_contents_eq(val, 4, val, 12, 2) => 1
- value_contents_eq(val, 4, val, 12, 4) => 0
- value_contents_eq(val, 3, val, 4, 4) => 0
+ 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:
then:
- value_contents_eq(val, 0, val, 2, 2) => 1
- value_contents_eq(val, 4, val, 6, 2) => 1
- value_contents_eq(val, 0, val, 4, 4) => 0
+ 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
after the inferior is gone, it works with const values. Therefore,
this routine must not be called with lazy values. */
-extern int value_contents_eq (const struct value *val1, LONGEST offset1,
- const struct value *val2, LONGEST offset2,
- LONGEST length);
+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
- EMBEDDED_OFFSET (that is, to &VAL->contents[EMBEDDED_OFFSET]).
- Marks value contents ranges as unavailable if the corresponding
- memory is likewise unavailable. STACK indicates whether the memory
- is known to be stack memory. */
+ 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 embedded_offset,
+extern void read_value_memory (struct value *val, LONGEST bit_offset,
int stack, CORE_ADDR memaddr,
gdb_byte *buffer, size_t length);
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 DOUBLEST value_as_double (struct value *val);
extern CORE_ADDR value_as_address (struct value *val);
extern LONGEST unpack_long (struct type *type, const gdb_byte *valaddr);
-extern DOUBLEST unpack_double (struct type *type, const gdb_byte *valaddr,
- int *invp);
extern CORE_ADDR unpack_pointer (struct type *type, const gdb_byte *valaddr);
extern LONGEST unpack_field_as_long (struct type *type,
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_double (struct type *type, DOUBLEST num);
-extern struct value *value_from_decfloat (struct type *type,
- const gdb_byte *decbytes);
+extern struct value *value_from_host_double (struct type *type, double d);
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 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,
extern LONGEST value_ptrdiff (struct value *arg1, struct value *arg2);
-extern int value_must_coerce_to_target (struct value *arg1);
+/* Return true if VAL does not live in target memory, but should in order
+ to operate on it. Otherwise return false. */
+
+extern bool value_must_coerce_to_target (struct value *arg1);
extern struct value *value_coerce_to_target (struct value *arg1);
extern struct value *value_addr (struct value *arg1);
-extern struct value *value_ref (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);
enum oload_search_type { NON_METHOD, METHOD, BOTH };
-extern int find_overload_match (struct value **args, int nargs,
+extern int find_overload_match (gdb::array_view<value *> args,
const char *name,
enum oload_search_type method,
struct value **objp, struct symbol *fsym,
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,
+ std::vector<value_ref_ptr> *val_chain,
int preserve_errors);
-extern char *extract_field_op (struct expression *exp, int *subexp);
+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 internalvar *create_internalvar (const char *name);
-extern VEC (char_ptr) *complete_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. */
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);
-
-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 value_ref_ptr release_value (struct value *val);
extern int record_latest_value (struct value *val);
extern void print_floating (const gdb_byte *valaddr, struct type *type,
struct ui_file *stream);
-extern void print_decimal_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);
struct ui_file *stream, int format,
enum val_prettyformat pretty);
-extern struct value *value_release_to_mark (const struct value *mark);
+/* Release values from the value chain and return them. Values
+ created after MARK are released. If MARK is nullptr, or if MARK is
+ not found on the value chain, then all values are released. Values
+ are returned in reverse order of creation; that is, newest
+ first. */
+
+extern std::vector<value_ref_ptr> value_release_to_mark
+ (const struct value *mark);
extern void val_print (struct type *type,
LONGEST embedded_offset, CORE_ADDR address,
extern struct value *value_allocate_space_in_inferior (int);
extern struct value *value_subscripted_rvalue (struct value *array,
- LONGEST index, int lowerbound);
+ LONGEST index,
+ LONGEST lowerbound);
/* User function handler. */
int argc,
struct value **argv);
-void add_internal_function (const char *name, const char *doc,
- internal_function_fn handler,
- void *cookie);
+/* Add a new internal function. NAME is the name of the function; DOC
+ is a documentation string describing the function. HANDLER is
+ called when the function is invoked. COOKIE is an arbitrary
+ pointer which is passed to HANDLER and is intended for "user
+ data". */
+
+extern void add_internal_function (const char *name, const char *doc,
+ internal_function_fn handler,
+ void *cookie);
+
+/* This overload takes an allocated documentation string. */
+
+extern void add_internal_function (gdb::unique_xmalloc_ptr<char> &&name,
+ gdb::unique_xmalloc_ptr<char> &&doc,
+ internal_function_fn handler,
+ void *cookie);
struct value *call_internal_function (struct gdbarch *gdbarch,
const struct language_defn *language,
char *value_internal_function_name (struct value *);
-extern struct value *value_of_xmethod (struct xmethod_worker *);
+/* 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);
+ gdb::array_view<value *> argv);
extern struct value *call_xmethod (struct value *method,
- int argc, struct value **argv);
+ gdb::array_view<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);
+
+/* Destroy the values currently allocated. This is called when GDB is
+ exiting (e.g., on quit_force). */
+extern void finalize_values ();
#endif /* !defined (VALUE_H) */