mirror of
https://sourceware.org/git/binutils-gdb.git
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ec471b627a
This removes finalize_values in favor of adding a new final cleanup. This is safe now that extension languages are explicitly shut down.
1708 lines
62 KiB
C++
1708 lines
62 KiB
C++
/* Definitions for values of C expressions, for GDB.
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Copyright (C) 1986-2024 Free Software Foundation, Inc.
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This file is part of GDB.
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This program is free software; you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation; either version 3 of the License, or
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(at your option) any later version.
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This program is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with this program. If not, see <http://www.gnu.org/licenses/>. */
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#if !defined (VALUE_H)
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#define VALUE_H 1
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#include "frame.h"
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#include "extension.h"
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#include "gdbsupport/gdb_ref_ptr.h"
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#include "gmp-utils.h"
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struct block;
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struct expression;
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struct regcache;
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struct symbol;
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struct type;
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struct ui_file;
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struct language_defn;
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struct value_print_options;
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/* Values can be partially 'optimized out' and/or 'unavailable'.
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These are distinct states and have different string representations
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and related error strings.
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'unavailable' has a specific meaning in this context. It means the
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value exists in the program (at the machine level), but GDB has no
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means to get to it. Such a value is normally printed as
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<unavailable>. Examples of how to end up with an unavailable value
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would be:
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- We're inspecting a traceframe, and the memory or registers the
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debug information says the value lives on haven't been collected.
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- We're inspecting a core dump, the memory or registers the debug
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information says the value lives aren't present in the dump
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(that is, we have a partial/trimmed core dump, or we don't fully
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understand/handle the core dump's format).
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- We're doing live debugging, but the debug API has no means to
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get at where the value lives in the machine, like e.g., ptrace
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not having access to some register or register set.
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- Any other similar scenario.
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OTOH, "optimized out" is about what the compiler decided to generate
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(or not generate). A chunk of a value that was optimized out does
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not actually exist in the program. There's no way to get at it
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short of compiling the program differently.
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A register that has not been saved in a frame is likewise considered
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optimized out, except not-saved registers have a different string
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representation and related error strings. E.g., we'll print them as
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<not-saved> instead of <optimized out>, as in:
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(gdb) p/x $rax
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$1 = <not saved>
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(gdb) info registers rax
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rax <not saved>
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If the debug info describes a variable as being in such a register,
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we'll still print the variable as <optimized out>. IOW, <not saved>
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is reserved for inspecting registers at the machine level.
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When comparing value contents, optimized out chunks, unavailable
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chunks, and valid contents data are all considered different. See
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value_contents_eq for more info.
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*/
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extern bool overload_resolution;
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/* Defines an [OFFSET, OFFSET + LENGTH) range. */
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struct range
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{
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/* Lowest offset in the range. */
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LONGEST offset;
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/* Length of the range. */
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ULONGEST length;
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/* Returns true if THIS is strictly less than OTHER, useful for
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searching. We keep ranges sorted by offset and coalesce
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overlapping and contiguous ranges, so this just compares the
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starting offset. */
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bool operator< (const range &other) const
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{
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return offset < other.offset;
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}
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/* Returns true if THIS is equal to OTHER. */
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bool operator== (const range &other) const
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{
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return offset == other.offset && length == other.length;
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}
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};
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/* A policy class to interface gdb::ref_ptr with struct value. */
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struct value_ref_policy
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{
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static void incref (struct value *ptr);
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static void decref (struct value *ptr);
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};
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/* A gdb:;ref_ptr pointer to a struct value. */
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typedef gdb::ref_ptr<struct value, value_ref_policy> value_ref_ptr;
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/* Note that the fields in this structure are arranged to save a bit
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of memory. */
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struct value
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{
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private:
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/* Values can only be created via "static constructors". */
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explicit value (struct type *type_)
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: m_modifiable (true),
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m_lazy (true),
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m_initialized (true),
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m_stack (false),
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m_is_zero (false),
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m_in_history (false),
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m_type (type_),
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m_enclosing_type (type_)
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{
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}
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/* Values can only be destroyed via the reference-counting
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mechanism. */
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~value ();
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DISABLE_COPY_AND_ASSIGN (value);
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public:
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/* Allocate a lazy value for type TYPE. Its actual content is
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"lazily" allocated too: the content field of the return value is
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NULL; it will be allocated when it is fetched from the target. */
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static struct value *allocate_lazy (struct type *type);
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/* Allocate a value and its contents for type TYPE. */
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static struct value *allocate (struct type *type);
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/* Allocate a lazy value representing register REGNUM in the frame previous
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to NEXT_FRAME. If TYPE is non-nullptr, use it as the value type.
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Otherwise, use `register_type` to obtain the type. */
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static struct value *allocate_register_lazy (const frame_info_ptr &next_frame,
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int regnum,
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type *type = nullptr);
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/* Same as `allocate_register_lazy`, but make the value non-lazy.
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The caller is responsible for filling the value's contents. */
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static struct value *allocate_register (const frame_info_ptr &next_frame,
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int regnum, type *type = nullptr);
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/* Create a computed lvalue, with type TYPE, function pointers
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FUNCS, and closure CLOSURE. */
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static struct value *allocate_computed (struct type *type,
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const struct lval_funcs *funcs,
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void *closure);
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/* Allocate NOT_LVAL value for type TYPE being OPTIMIZED_OUT. */
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static struct value *allocate_optimized_out (struct type *type);
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/* Create a value of type TYPE that is zero, and return it. */
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static struct value *zero (struct type *type, enum lval_type lv);
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/* Return a copy of the value. It contains the same contents, for
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the same memory address, but it's a different block of
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storage. */
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struct value *copy () const;
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/* Type of the value. */
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struct type *type () const
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{ return m_type; }
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/* This is being used to change the type of an existing value, that
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code should instead be creating a new value with the changed type
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(but possibly shared content). */
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void deprecated_set_type (struct type *type)
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{ m_type = type; }
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/* Return the gdbarch associated with the value. */
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struct gdbarch *arch () const;
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/* Only used for bitfields; number of bits contained in them. */
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LONGEST bitsize () const
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{ return m_bitsize; }
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void set_bitsize (LONGEST bit)
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{ m_bitsize = bit; }
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/* Only used for bitfields; position of start of field. For
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little-endian targets, it is the position of the LSB. For
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big-endian targets, it is the position of the MSB. */
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LONGEST bitpos () const
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{ return m_bitpos; }
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void set_bitpos (LONGEST bit)
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{ m_bitpos = bit; }
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/* Only used for bitfields; the containing value. This allows a
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single read from the target when displaying multiple
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bitfields. */
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value *parent () const
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{ return m_parent.get (); }
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void set_parent (struct value *parent)
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{ m_parent = value_ref_ptr::new_reference (parent); }
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/* Describes offset of a value within lval of a structure in bytes.
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If lval == lval_memory, this is an offset to the address. If
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lval == lval_register, this is a further offset from
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location.address within the registers structure. Note also the
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member embedded_offset below. */
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LONGEST offset () const
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{ return m_offset; }
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void set_offset (LONGEST offset)
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{ m_offset = offset; }
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/* The comment from "struct value" reads: ``Is it modifiable? Only
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relevant if lval != not_lval.''. Shouldn't the value instead be
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not_lval and be done with it? */
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bool deprecated_modifiable () const
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{ return m_modifiable; }
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/* Set or clear the modifiable flag. */
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void set_modifiable (bool val)
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{ m_modifiable = val; }
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LONGEST pointed_to_offset () const
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{ return m_pointed_to_offset; }
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void set_pointed_to_offset (LONGEST val)
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{ m_pointed_to_offset = val; }
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LONGEST embedded_offset () const
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{ return m_embedded_offset; }
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void set_embedded_offset (LONGEST val)
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{ m_embedded_offset = val; }
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/* If false, contents of this value are in the contents field. If
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true, contents are in inferior. If the lval field is lval_memory,
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the contents are in inferior memory at location.address plus offset.
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The lval field may also be lval_register.
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WARNING: This field is used by the code which handles watchpoints
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(see breakpoint.c) to decide whether a particular value can be
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watched by hardware watchpoints. If the lazy flag is set for some
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member of a value chain, it is assumed that this member of the
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chain doesn't need to be watched as part of watching the value
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itself. This is how GDB avoids watching the entire struct or array
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when the user wants to watch a single struct member or array
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element. If you ever change the way lazy flag is set and reset, be
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sure to consider this use as well! */
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bool lazy () const
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{ return m_lazy; }
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void set_lazy (bool val)
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{ m_lazy = val; }
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/* If a value represents a C++ object, then the `type' field gives the
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object's compile-time type. If the object actually belongs to some
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class derived from `type', perhaps with other base classes and
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additional members, then `type' is just a subobject of the real
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thing, and the full object is probably larger than `type' would
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suggest.
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If `type' is a dynamic class (i.e. one with a vtable), then GDB can
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actually determine the object's run-time type by looking at the
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run-time type information in the vtable. When this information is
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available, we may elect to read in the entire object, for several
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reasons:
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- When printing the value, the user would probably rather see the
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full object, not just the limited portion apparent from the
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compile-time type.
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- If `type' has virtual base classes, then even printing `type'
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alone may require reaching outside the `type' portion of the
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object to wherever the virtual base class has been stored.
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When we store the entire object, `enclosing_type' is the run-time
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type -- the complete object -- and `embedded_offset' is the offset
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of `type' within that larger type, in bytes. The contents()
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method takes `embedded_offset' into account, so most GDB code
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continues to see the `type' portion of the value, just as the
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inferior would.
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If `type' is a pointer to an object, then `enclosing_type' is a
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pointer to the object's run-time type, and `pointed_to_offset' is
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the offset in bytes from the full object to the pointed-to object
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-- that is, the value `embedded_offset' would have if we followed
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the pointer and fetched the complete object. (I don't really see
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the point. Why not just determine the run-time type when you
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indirect, and avoid the special case? The contents don't matter
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until you indirect anyway.)
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If we're not doing anything fancy, `enclosing_type' is equal to
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`type', and `embedded_offset' is zero, so everything works
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normally. */
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struct type *enclosing_type () const
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{ return m_enclosing_type; }
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void set_enclosing_type (struct type *new_type);
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bool stack () const
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{ return m_stack; }
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void set_stack (bool val)
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{ m_stack = val; }
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/* If this value is lval_computed, return its lval_funcs
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structure. */
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const struct lval_funcs *computed_funcs () const;
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/* If this value is lval_computed, return its closure. The meaning
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of the returned value depends on the functions this value
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uses. */
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void *computed_closure () const;
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enum lval_type lval () const
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{ return m_lval; }
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/* Set the 'lval' of this value. */
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void set_lval (lval_type val)
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{ m_lval = val; }
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/* Set or return field indicating whether a variable is initialized or
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not, based on debugging information supplied by the compiler.
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true = initialized; false = uninitialized. */
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bool initialized () const
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{ return m_initialized; }
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void set_initialized (bool value)
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{ m_initialized = value; }
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/* If lval == lval_memory, return the address in the inferior. If
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lval == lval_register, return the byte offset into the registers
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structure. Otherwise, return 0. The returned address
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includes the offset, if any. */
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CORE_ADDR address () const;
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/* Like address, except the result does not include value's
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offset. */
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CORE_ADDR raw_address () const;
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/* Set the address of a value. */
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void set_address (CORE_ADDR);
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struct internalvar **deprecated_internalvar_hack ()
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{ return &m_location.internalvar; }
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/* Return this value's next frame id.
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The value must be of lval == lval_register. */
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frame_id next_frame_id ()
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{
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gdb_assert (m_lval == lval_register);
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return m_location.reg.next_frame_id;
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}
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/* Return this value's register number.
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The value must be of lval == lval_register. */
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int regnum ()
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{
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gdb_assert (m_lval == lval_register);
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return m_location.reg.regnum;
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}
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/* contents() and contents_raw() both return the address of the gdb
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buffer used to hold a copy of the contents of the lval.
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contents() is used when the contents of the buffer are needed --
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it uses fetch_lazy() to load the buffer from the process being
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debugged if it hasn't already been loaded (contents_writeable()
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is used when a writeable but fetched buffer is required)..
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contents_raw() is used when data is being stored into the buffer,
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or when it is certain that the contents of the buffer are valid.
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Note: The contents pointer is adjusted by the offset required to
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get to the real subobject, if the value happens to represent
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something embedded in a larger run-time object. */
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gdb::array_view<gdb_byte> contents_raw ();
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/* Actual contents of the value. For use of this value; setting it
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uses the stuff above. Not valid if lazy is nonzero. Target
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byte-order. We force it to be aligned properly for any possible
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value. Note that a value therefore extends beyond what is
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declared here. */
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gdb::array_view<const gdb_byte> contents ();
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/* The ALL variants of the above two methods do not adjust the
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returned pointer by the embedded_offset value. */
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gdb::array_view<const gdb_byte> contents_all ();
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gdb::array_view<gdb_byte> contents_all_raw ();
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gdb::array_view<gdb_byte> contents_writeable ();
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/* Like contents_all, but does not require that the returned bits be
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||
valid. This should only be used in situations where you plan to
|
||
check the validity manually. */
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gdb::array_view<const gdb_byte> contents_for_printing ();
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||
/* Like contents_for_printing, but accepts a constant value pointer.
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Unlike contents_for_printing however, the pointed value must
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_not_ be lazy. */
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gdb::array_view<const gdb_byte> contents_for_printing () const;
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/* Load the actual content of a lazy value. Fetch the data from the
|
||
user's process and clear the lazy flag to indicate that the data in
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||
the buffer is valid.
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||
|
||
If the value is zero-length, we avoid calling read_memory, which
|
||
would abort. We mark the value as fetched anyway -- all 0 bytes of
|
||
it. */
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void fetch_lazy ();
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||
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||
/* Compare LENGTH bytes of this value's contents starting at OFFSET1
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||
with LENGTH bytes of VAL2's contents starting at OFFSET2.
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||
|
||
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:
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||
|
||
int len = check_typedef (val->enclosing_type ())->length ();
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val->contents_eq (0, val, 0, len);
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|
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Returns true iff the set of available/valid contents match.
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||
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||
Optimized-out contents are equal to optimized-out contents, and are
|
||
not equal to non-optimized-out contents.
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||
|
||
Unavailable contents are equal to unavailable contents, and are not
|
||
equal to non-unavailable contents.
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||
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||
For example, if 'x's represent an unavailable byte, and 'V' and 'Z'
|
||
represent different available/valid bytes, in a value with length
|
||
16:
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||
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||
offset: 0 4 8 12 16
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||
contents: xxxxVVVVxxxxVVZZ
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||
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||
then:
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||
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||
val->contents_eq(0, val, 8, 6) => true
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||
val->contents_eq(0, val, 4, 4) => false
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||
val->contents_eq(0, val, 8, 8) => false
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||
val->contents_eq(4, val, 12, 2) => true
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||
val->contents_eq(4, val, 12, 4) => true
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val->contents_eq(3, val, 4, 4) => true
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||
If 'x's represent an unavailable byte, 'o' represents an optimized
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out byte, in a value with length 8:
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||
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offset: 0 4 8
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contents: xxxxoooo
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then:
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val->contents_eq(0, val, 2, 2) => true
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||
val->contents_eq(4, val, 6, 2) => true
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||
val->contents_eq(0, val, 4, 4) => true
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||
|
||
We only know whether a value chunk is unavailable or optimized out
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||
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. */
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||
|
||
bool contents_eq (LONGEST offset1, const struct value *val2, LONGEST offset2,
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||
LONGEST length) const;
|
||
|
||
/* An overload of contents_eq that compares the entirety of both
|
||
values. */
|
||
bool contents_eq (const struct value *val2) const;
|
||
|
||
/* Given a value, determine whether the bits starting at OFFSET and
|
||
extending for LENGTH bits are a synthetic pointer. */
|
||
|
||
bool bits_synthetic_pointer (LONGEST offset, LONGEST length) const;
|
||
|
||
/* Increase this value's reference count. */
|
||
void incref ()
|
||
{ ++m_reference_count; }
|
||
|
||
/* Decrease this value's reference count. When the reference count
|
||
drops to 0, it will be freed. */
|
||
void decref ();
|
||
|
||
/* Given a value, determine whether the contents bytes starting at
|
||
OFFSET and extending for LENGTH bytes are available. This returns
|
||
true if all bytes in the given range are available, false if any
|
||
byte is unavailable. */
|
||
bool bytes_available (LONGEST offset, ULONGEST length) const;
|
||
|
||
/* Given a value, determine whether the contents bits starting at
|
||
OFFSET and extending for LENGTH bits are available. This returns
|
||
true if all bits in the given range are available, false if any
|
||
bit is unavailable. */
|
||
bool bits_available (LONGEST offset, ULONGEST length) const;
|
||
|
||
/* Like bytes_available, but return false if any byte in the
|
||
whole object is unavailable. */
|
||
bool entirely_available ();
|
||
|
||
/* Like entirely_available, but return false if any byte in the
|
||
whole object is available. */
|
||
bool entirely_unavailable ()
|
||
{ return entirely_covered_by_range_vector (m_unavailable); }
|
||
|
||
/* Mark this value's content bytes starting at OFFSET and extending
|
||
for LENGTH bytes as unavailable. */
|
||
void mark_bytes_unavailable (LONGEST offset, ULONGEST length);
|
||
|
||
/* Mark this value's content bits starting at OFFSET and extending
|
||
for LENGTH bits as unavailable. */
|
||
void mark_bits_unavailable (LONGEST offset, ULONGEST length);
|
||
|
||
/* If true, 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. */
|
||
bool optimized_out ();
|
||
|
||
/* Given a value, return true if any of the contents bits starting at
|
||
OFFSET and extending for LENGTH bits is optimized out, false
|
||
otherwise. */
|
||
bool bits_any_optimized_out (int bit_offset, int bit_length) const;
|
||
|
||
/* Like optimized_out, but return true iff the whole value is
|
||
optimized out. */
|
||
bool entirely_optimized_out ()
|
||
{
|
||
return entirely_covered_by_range_vector (m_optimized_out);
|
||
}
|
||
|
||
/* Mark this value's content bytes starting at OFFSET and extending
|
||
for LENGTH bytes as optimized out. */
|
||
void mark_bytes_optimized_out (int offset, int length);
|
||
|
||
/* Mark this value's content bits starting at OFFSET and extending
|
||
for LENGTH bits as optimized out. */
|
||
void mark_bits_optimized_out (LONGEST offset, LONGEST length);
|
||
|
||
/* Return a version of this that is non-lvalue. */
|
||
struct value *non_lval ();
|
||
|
||
/* Write contents of this value at ADDR and set its lval type to be
|
||
LVAL_MEMORY. */
|
||
void force_lval (CORE_ADDR);
|
||
|
||
/* Set this values's location as appropriate for a component of
|
||
WHOLE --- regardless of what kind of lvalue WHOLE is. */
|
||
void set_component_location (const struct value *whole);
|
||
|
||
/* Build a value wrapping and representing WORKER. The value takes
|
||
ownership of the xmethod_worker object. */
|
||
static struct value *from_xmethod (xmethod_worker_up &&worker);
|
||
|
||
/* Return the type of the result of TYPE_CODE_XMETHOD value METHOD. */
|
||
struct type *result_type_of_xmethod (gdb::array_view<value *> argv);
|
||
|
||
/* Call the xmethod corresponding to the TYPE_CODE_XMETHOD value
|
||
METHOD. */
|
||
struct value *call_xmethod (gdb::array_view<value *> argv);
|
||
|
||
/* Update this value before discarding OBJFILE. COPIED_TYPES is
|
||
used to prevent cycles / duplicates. */
|
||
void preserve (struct objfile *objfile, htab_t copied_types);
|
||
|
||
/* Unpack a bitfield of BITSIZE bits found at BITPOS in the object
|
||
at VALADDR + EMBEDDEDOFFSET that has the type of DEST_VAL and
|
||
store the contents in DEST_VAL, zero or sign extending if the
|
||
type of DEST_VAL is wider than BITSIZE. VALADDR points to the
|
||
contents of this value. If this value's contents required to
|
||
extract the bitfield from are unavailable/optimized out, DEST_VAL
|
||
is correspondingly marked unavailable/optimized out. */
|
||
void unpack_bitfield (struct value *dest_val,
|
||
LONGEST bitpos, LONGEST bitsize,
|
||
const gdb_byte *valaddr, LONGEST embedded_offset)
|
||
const;
|
||
|
||
/* Copy LENGTH bytes of this value's (all) contents
|
||
(value_contents_all) starting at SRC_OFFSET byte, into DST
|
||
value's (all) contents, starting at DST_OFFSET. If unavailable
|
||
contents are being copied from this value, the corresponding DST
|
||
contents are marked unavailable accordingly. DST must not be
|
||
lazy. If this value is lazy, it will be fetched now.
|
||
|
||
It is assumed the contents of DST in the [DST_OFFSET,
|
||
DST_OFFSET+LENGTH) range are wholly available. */
|
||
void contents_copy (struct value *dst, LONGEST dst_offset,
|
||
LONGEST src_offset, LONGEST length);
|
||
|
||
/* Given a value (offset by OFFSET bytes)
|
||
of a struct or union type ARG_TYPE,
|
||
extract and return the value of one of its (non-static) fields.
|
||
FIELDNO says which field. */
|
||
struct value *primitive_field (LONGEST offset, int fieldno,
|
||
struct type *arg_type);
|
||
|
||
/* Create a new value by extracting it from this value. TYPE is the
|
||
type of the new value. BIT_OFFSET and BIT_LENGTH describe the
|
||
offset and field width of the value to extract from this value --
|
||
BIT_LENGTH may differ from TYPE's length in the case where this
|
||
value's type is packed.
|
||
|
||
When the value does come from a non-byte-aligned offset or field
|
||
width, it will be marked non_lval. */
|
||
struct value *from_component_bitsize (struct type *type,
|
||
LONGEST bit_offset,
|
||
LONGEST bit_length);
|
||
|
||
/* Record this value on the value history, and return its location
|
||
in the history. The value is removed from the value chain. */
|
||
int record_latest ();
|
||
|
||
private:
|
||
|
||
/* Type of value; either not an lval, or one of the various
|
||
different possible kinds of lval. */
|
||
enum lval_type m_lval = not_lval;
|
||
|
||
/* Is it modifiable? Only relevant if lval != not_lval. */
|
||
bool m_modifiable : 1;
|
||
|
||
/* If false, contents of this value are in the contents field. If
|
||
true, 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! */
|
||
bool m_lazy : 1;
|
||
|
||
/* If value is a variable, is it initialized or not. */
|
||
bool m_initialized : 1;
|
||
|
||
/* If value is from the stack. If this is set, read_stack will be
|
||
used instead of read_memory to enable extra caching. */
|
||
bool m_stack : 1;
|
||
|
||
/* True if this is a zero value, created by 'value::zero'; false
|
||
otherwise. */
|
||
bool m_is_zero : 1;
|
||
|
||
/* True if this a value recorded in value history; false otherwise. */
|
||
bool m_in_history : 1;
|
||
|
||
/* Location of value (if lval). */
|
||
union
|
||
{
|
||
/* If lval == lval_memory, this is the address in the inferior */
|
||
CORE_ADDR address;
|
||
|
||
/*If lval == lval_register, the value is from a register. */
|
||
struct
|
||
{
|
||
/* Register number. */
|
||
int regnum;
|
||
|
||
/* Frame ID of the next physical (non-inline) frame to which a register
|
||
value is relative. */
|
||
frame_id next_frame_id;
|
||
} reg;
|
||
|
||
/* Pointer to internal variable. */
|
||
struct internalvar *internalvar;
|
||
|
||
/* Pointer to xmethod worker. */
|
||
struct xmethod_worker *xm_worker;
|
||
|
||
/* If lval == lval_computed, this is a set of function pointers
|
||
to use to access and describe the value, and a closure pointer
|
||
for them to use. */
|
||
struct
|
||
{
|
||
/* Functions to call. */
|
||
const struct lval_funcs *funcs;
|
||
|
||
/* Closure for those functions to use. */
|
||
void *closure;
|
||
} computed;
|
||
} m_location {};
|
||
|
||
/* Describes offset of a value within lval of a structure in target
|
||
addressable memory units. Note also the member embedded_offset
|
||
below. */
|
||
LONGEST m_offset = 0;
|
||
|
||
/* Only used for bitfields; number of bits contained in them. */
|
||
LONGEST m_bitsize = 0;
|
||
|
||
/* Only used for bitfields; position of start of field. For
|
||
little-endian targets, it is the position of the LSB. For
|
||
big-endian targets, it is the position of the MSB. */
|
||
LONGEST m_bitpos = 0;
|
||
|
||
/* The number of references to this value. When a value is created,
|
||
the value chain holds a reference, so REFERENCE_COUNT is 1. If
|
||
release_value is called, this value is removed from the chain but
|
||
the caller of release_value now has a reference to this value.
|
||
The caller must arrange for a call to value_free later. */
|
||
int m_reference_count = 1;
|
||
|
||
/* Only used for bitfields; the containing value. This allows a
|
||
single read from the target when displaying multiple
|
||
bitfields. */
|
||
value_ref_ptr m_parent;
|
||
|
||
/* Type of the value. */
|
||
struct type *m_type;
|
||
|
||
/* 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 target addressable memory
|
||
units. The contents() method 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 target addressable memory units 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. */
|
||
struct type *m_enclosing_type;
|
||
LONGEST m_embedded_offset = 0;
|
||
LONGEST m_pointed_to_offset = 0;
|
||
|
||
/* Actual contents of the value. Target byte-order.
|
||
|
||
May be nullptr if the value is lazy or is entirely optimized out.
|
||
Guaranteed to be non-nullptr otherwise. */
|
||
gdb::unique_xmalloc_ptr<gdb_byte> m_contents;
|
||
|
||
/* Unavailable ranges in CONTENTS. We mark unavailable ranges,
|
||
rather than available, since the common and default case is for a
|
||
value to be available. This is filled in at value read time.
|
||
The unavailable ranges are tracked in bits. Note that a contents
|
||
bit that has been optimized out doesn't really exist in the
|
||
program, so it can't be marked unavailable either. */
|
||
std::vector<range> m_unavailable;
|
||
|
||
/* Likewise, but for optimized out contents (a chunk of the value of
|
||
a variable that does not actually exist in the program). If LVAL
|
||
is lval_register, this is a register ($pc, $sp, etc., never a
|
||
program variable) that has not been saved in the frame. Not
|
||
saved registers and optimized-out program variables values are
|
||
treated pretty much the same, except not-saved registers have a
|
||
different string representation and related error strings. */
|
||
std::vector<range> m_optimized_out;
|
||
|
||
/* This is only non-zero for values of TYPE_CODE_ARRAY and if the size of
|
||
the array in inferior memory is greater than max_value_size. If these
|
||
conditions are met then, when the value is loaded from the inferior
|
||
GDB will only load a portion of the array into memory, and
|
||
limited_length will be set to indicate the length in octets that were
|
||
loaded from the inferior. */
|
||
ULONGEST m_limited_length = 0;
|
||
|
||
/* Allocate a value and its contents for type TYPE. If CHECK_SIZE
|
||
is true, then apply the usual max-value-size checks. */
|
||
static struct value *allocate (struct type *type, bool check_size);
|
||
|
||
/* Helper for fetch_lazy when the value is a bitfield. */
|
||
void fetch_lazy_bitfield ();
|
||
|
||
/* Helper for fetch_lazy when the value is in memory. */
|
||
void fetch_lazy_memory ();
|
||
|
||
/* Helper for fetch_lazy when the value is in a register. */
|
||
void fetch_lazy_register ();
|
||
|
||
/* Try to limit ourselves to only fetching the limited number of
|
||
elements. However, if this limited number of elements still
|
||
puts us over max_value_size, then we still refuse it and
|
||
return failure here, which will ultimately throw an error. */
|
||
bool set_limited_array_length ();
|
||
|
||
/* Allocate the contents of this value if it has not been allocated
|
||
yet. If CHECK_SIZE is true, then apply the usual max-value-size
|
||
checks. */
|
||
void allocate_contents (bool check_size);
|
||
|
||
/* Helper function for value_contents_eq. The only difference is that
|
||
this function is bit rather than byte based.
|
||
|
||
Compare LENGTH bits of this value's contents starting at OFFSET1
|
||
bits with LENGTH bits of VAL2's contents starting at OFFSET2
|
||
bits. Return true if the available bits match. */
|
||
bool contents_bits_eq (int offset1, const struct value *val2, int offset2,
|
||
int length) const;
|
||
|
||
void require_not_optimized_out () const;
|
||
void require_available () const;
|
||
|
||
/* Returns true if this value is entirely covered by RANGES. If the
|
||
value is lazy, it'll be read now. Note that RANGE is a pointer
|
||
to pointer because reading the value might change *RANGE. */
|
||
bool entirely_covered_by_range_vector (const std::vector<range> &ranges);
|
||
|
||
/* Copy the ranges metadata from this value that overlaps
|
||
[SRC_BIT_OFFSET, SRC_BIT_OFFSET+BIT_LENGTH) into DST,
|
||
adjusted. */
|
||
void ranges_copy_adjusted (struct value *dst, int dst_bit_offset,
|
||
int src_bit_offset, int bit_length) const;
|
||
|
||
/* Copy LENGTH target addressable memory units of this value's (all)
|
||
contents (value_contents_all) starting at SRC_OFFSET, into DST
|
||
value's (all) contents, starting at DST_OFFSET. If unavailable
|
||
contents are being copied from this, the corresponding DST
|
||
contents are marked unavailable accordingly. Neither DST nor
|
||
this value may be lazy values.
|
||
|
||
It is assumed the contents of DST in the [DST_OFFSET,
|
||
DST_OFFSET+LENGTH) range are wholly available. */
|
||
void contents_copy_raw (struct value *dst, LONGEST dst_offset,
|
||
LONGEST src_offset, LONGEST length);
|
||
|
||
/* A helper for value_from_component_bitsize that copies bits from
|
||
this value to DEST. */
|
||
void contents_copy_raw_bitwise (struct value *dst, LONGEST dst_bit_offset,
|
||
LONGEST src_bit_offset, LONGEST bit_length);
|
||
};
|
||
|
||
inline void
|
||
value_ref_policy::incref (struct value *ptr)
|
||
{
|
||
ptr->incref ();
|
||
}
|
||
|
||
inline void
|
||
value_ref_policy::decref (struct value *ptr)
|
||
{
|
||
ptr->decref ();
|
||
}
|
||
|
||
/* 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);
|
||
|
||
/* 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);
|
||
|
||
/* Return true if any part of V is optimized out, false otherwise.
|
||
This will only be called for lazy values -- if the value has been
|
||
fetched, then the value's optimized-out bits are consulted
|
||
instead. */
|
||
bool (*is_optimized_out) (struct value *v);
|
||
|
||
/* 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. */
|
||
bool (*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);
|
||
};
|
||
|
||
/* Throw an error complaining that the value has been optimized
|
||
out. */
|
||
|
||
extern void error_value_optimized_out (void);
|
||
|
||
/* Pointer to internal variable. */
|
||
#define VALUE_INTERNALVAR(val) (*((val)->deprecated_internalvar_hack ()))
|
||
|
||
/* 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. ORIGINAL_VALUE_ADDRESS is the address within VALUE, that is
|
||
the address that was dereferenced.
|
||
|
||
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,
|
||
struct value *original_val,
|
||
CORE_ADDR original_value_address);
|
||
|
||
/* 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);
|
||
|
||
/* 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,
|
||
bool 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"
|
||
|
||
class frame_info_ptr;
|
||
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);
|
||
|
||
/* Extract the value from VAL as a MPZ. This coerces arrays and
|
||
handles various integer-like types as well. */
|
||
|
||
extern gdb_mpz value_as_mpz (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);
|
||
|
||
/* Unpack a bitfield of the specified FIELD_TYPE, from the object at
|
||
VALADDR, and store the result in *RESULT.
|
||
The bitfield starts at BITPOS bits and contains BITSIZE bits; if
|
||
BITSIZE is zero, then the length is taken from FIELD_TYPE.
|
||
|
||
Extracting bits depends on endianness of the machine. Compute the
|
||
number of least significant bits to discard. For big endian machines,
|
||
we compute the total number of bits in the anonymous object, subtract
|
||
off the bit count from the MSB of the object to the MSB of the
|
||
bitfield, then the size of the bitfield, which leaves the LSB discard
|
||
count. For little endian machines, the discard count is simply the
|
||
number of bits from the LSB of the anonymous object to the LSB of the
|
||
bitfield.
|
||
|
||
If the field is signed, we also do sign extension. */
|
||
|
||
extern LONGEST unpack_bits_as_long (struct type *field_type,
|
||
const gdb_byte *valaddr,
|
||
LONGEST bitpos, LONGEST bitsize);
|
||
|
||
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 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_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);
|
||
|
||
/* Convert the value V into a newly allocated value. */
|
||
extern struct value *value_from_mpz (struct type *type, const gdb_mpz &v);
|
||
|
||
extern struct value *value_at (struct type *type, CORE_ADDR addr);
|
||
|
||
/* Return a new value given a type and an address. The new value is
|
||
lazy. If FRAME is given, it is used when resolving dynamic
|
||
properties. */
|
||
|
||
extern struct value *value_at_lazy (struct type *type, CORE_ADDR addr,
|
||
const frame_info_ptr &frame = nullptr);
|
||
|
||
/* Like value_at, but ensures that the result is marked not_lval.
|
||
This can be important if the memory is "volatile". */
|
||
extern struct value *value_at_non_lval (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,
|
||
const frame_info_ptr &frame = nullptr);
|
||
extern struct value *value_from_contents (struct type *, const gdb_byte *);
|
||
|
||
extern value *default_value_from_register (gdbarch *gdbarch, type *type,
|
||
int regnum,
|
||
const frame_info_ptr &this_frame);
|
||
|
||
extern struct value *value_from_register (struct type *type, int regnum,
|
||
const frame_info_ptr &frame);
|
||
|
||
extern CORE_ADDR address_from_register (int regnum,
|
||
const frame_info_ptr &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);
|
||
|
||
/* Return a value with the contents of register REGNUM as found in the frame
|
||
previous to NEXT_FRAME. */
|
||
|
||
extern value *value_of_register (int regnum, const frame_info_ptr &next_frame);
|
||
|
||
/* Same as the above, but the value is not fetched. */
|
||
|
||
extern value *value_of_register_lazy (const frame_info_ptr &next_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,
|
||
const frame_info_ptr &frame);
|
||
|
||
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_freed)
|
||
{
|
||
value_free_to_mark (m_value);
|
||
m_freed = true;
|
||
}
|
||
}
|
||
|
||
private:
|
||
|
||
const struct value *m_value;
|
||
bool m_freed = false;
|
||
};
|
||
|
||
/* Create not_lval value representing a NULL-terminated C string. The
|
||
resulting value has type TYPE_CODE_ARRAY. The string passed in should
|
||
not include embedded null characters.
|
||
|
||
PTR points to the string data; COUNT is number of characters (does
|
||
not include the NULL terminator) pointed to by PTR, each character is of
|
||
type (and size of) CHAR_TYPE. */
|
||
|
||
extern struct value *value_cstring (const gdb_byte *ptr, ssize_t count,
|
||
struct type *char_type);
|
||
|
||
/* Specialisation of value_cstring above. In this case PTR points to
|
||
single byte characters. CHAR_TYPE must have a length of 1. */
|
||
inline struct value *value_cstring (const char *ptr, ssize_t count,
|
||
struct type *char_type)
|
||
{
|
||
gdb_assert (char_type->length () == 1);
|
||
return value_cstring ((const gdb_byte *) ptr, count, char_type);
|
||
}
|
||
|
||
/* Create a not_lval value with type TYPE_CODE_STRING, the resulting value
|
||
has type TYPE_CODE_STRING.
|
||
|
||
PTR points to the string data; COUNT is number of characters pointed to
|
||
by PTR, each character has the type (and size of) CHAR_TYPE.
|
||
|
||
Note that string types are like array of char types with a lower bound
|
||
defined by the language (usually zero or one). Also the string may
|
||
contain embedded null characters. */
|
||
|
||
extern struct value *value_string (const gdb_byte *ptr, ssize_t count,
|
||
struct type *char_type);
|
||
|
||
/* Specialisation of value_string above. In this case PTR points to
|
||
single byte characters. CHAR_TYPE must have a length of 1. */
|
||
inline struct value *value_string (const char *ptr, ssize_t count,
|
||
struct type *char_type)
|
||
{
|
||
gdb_assert (char_type->length () == 1);
|
||
return value_string ((const gdb_byte *) ptr, count, char_type);
|
||
}
|
||
|
||
extern struct value *value_array (int lowbound,
|
||
gdb::array_view<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);
|
||
|
||
/* 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_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);
|
||
|
||
/* The unary + operation. */
|
||
extern struct value *value_pos (struct value *arg1);
|
||
|
||
/* The unary - operation. */
|
||
extern struct value *value_neg (struct value *arg1);
|
||
|
||
/* The unary ~ operation -- but note that it also implements the GCC
|
||
extension, where ~ of a complex number is the complex
|
||
conjugate. */
|
||
extern struct value *value_complement (struct value *arg1);
|
||
|
||
extern struct value *value_struct_elt (struct value **argp,
|
||
std::optional<gdb::array_view <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 (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,
|
||
enum noside noside);
|
||
|
||
extern struct value *value_field (struct value *arg1, int fieldno);
|
||
|
||
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_one (struct type *type);
|
||
|
||
extern struct value *value_repeat (struct value *arg1, int count);
|
||
|
||
extern struct value *value_subscript (struct value *array, LONGEST index);
|
||
|
||
/* Assuming VAL is array-like (see type::is_array_like), return an
|
||
array form of VAL. */
|
||
extern struct value *value_to_array (struct value *val);
|
||
|
||
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_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 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);
|
||
|
||
namespace expr { class operation; };
|
||
extern void fetch_subexp_value (struct expression *exp,
|
||
expr::operation *op,
|
||
struct value **valp, struct value **resultp,
|
||
std::vector<value_ref_ptr> *val_chain,
|
||
bool preserve_errors);
|
||
|
||
extern struct value *parse_and_eval (const char *exp, parser_flags flags = 0);
|
||
|
||
extern struct value *parse_to_comma_and_eval (const char **expp);
|
||
|
||
extern struct type *parse_and_eval_type (const 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);
|
||
|
||
/* Return the number of items in the value history. */
|
||
|
||
extern ULONGEST value_history_count ();
|
||
|
||
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);
|
||
};
|
||
|
||
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);
|
||
|
||
/* Simulate the C operator ! -- return true if ARG1 contains zero. */
|
||
extern bool value_logical_not (struct value *arg1);
|
||
|
||
/* Returns true if the value VAL represents a true value. */
|
||
static inline bool
|
||
value_true (struct value *val)
|
||
{
|
||
return !value_logical_not (val);
|
||
}
|
||
|
||
/* 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 value_ref_ptr release_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);
|
||
|
||
/* 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 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,
|
||
const frame_info_ptr &frame,
|
||
struct ui_file *stream,
|
||
int indent);
|
||
|
||
extern void typedef_print (struct type *type, struct symbol *news,
|
||
struct ui_file *stream);
|
||
|
||
extern const char *internalvar_name (const struct internalvar *var);
|
||
|
||
extern void preserve_values (struct objfile *);
|
||
|
||
/* From values.c */
|
||
|
||
extern struct value *make_cv_value (int, int, struct value *);
|
||
|
||
/* From valops.c */
|
||
|
||
extern struct value *varying_to_slice (struct value *);
|
||
|
||
extern struct value *value_slice (struct value *, int, int);
|
||
|
||
/* Create a complex number. The type is the complex type; the values
|
||
are cast to the underlying scalar type before the complex number is
|
||
created. */
|
||
|
||
extern struct value *value_literal_complex (struct value *, struct value *,
|
||
struct type *);
|
||
|
||
/* Return the real part of a complex value. */
|
||
|
||
extern struct value *value_real_part (struct value *value);
|
||
|
||
/* Return the imaginary part of a complex value. */
|
||
|
||
extern struct value *value_imaginary_part (struct value *value);
|
||
|
||
extern struct value *find_function_in_inferior (const char *,
|
||
struct objfile **);
|
||
|
||
extern struct value *value_allocate_space_in_inferior (int);
|
||
|
||
/* User function handler. */
|
||
|
||
typedef struct value *(*internal_function_fn) (struct gdbarch *gdbarch,
|
||
const struct language_defn *language,
|
||
void *cookie,
|
||
int argc,
|
||
struct value **argv);
|
||
|
||
/* 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,
|
||
struct value *function,
|
||
int argc, struct value **argv);
|
||
|
||
const char *value_internal_function_name (struct value *);
|
||
|
||
/* Convert VALUE to a gdb_mpq. The caller must ensure that VALUE is
|
||
of floating-point, fixed-point, or integer type. */
|
||
extern gdb_mpq value_to_gdb_mpq (struct value *value);
|
||
|
||
/* Return true if LEN (in bytes) exceeds the max-value-size setting,
|
||
otherwise, return false. If the user has disabled (set to unlimited)
|
||
the max-value-size setting then this function will always return false. */
|
||
extern bool exceeds_max_value_size (ULONGEST length);
|
||
|
||
/* While an instance of this class is live, and array values that are
|
||
created, that are larger than max_value_size, will be restricted in size
|
||
to a particular number of elements. */
|
||
|
||
struct scoped_array_length_limiting
|
||
{
|
||
/* Limit any large array values to only contain ELEMENTS elements. */
|
||
scoped_array_length_limiting (int elements);
|
||
|
||
/* Restore the previous array value limit. */
|
||
~scoped_array_length_limiting ();
|
||
|
||
private:
|
||
/* Used to hold the previous array value element limit. */
|
||
std::optional<int> m_old_value;
|
||
};
|
||
|
||
/* Helpers for building pseudo register values from raw registers. */
|
||
|
||
/* Create a value for pseudo register PSEUDO_REG_NUM by using bytes from
|
||
raw register RAW_REG_NUM starting at RAW_OFFSET.
|
||
|
||
The size of the pseudo register specifies how many bytes to use. The
|
||
offset plus the size must not overflow the raw register's size. */
|
||
|
||
value *pseudo_from_raw_part (const frame_info_ptr &next_frame, int pseudo_reg_num,
|
||
int raw_reg_num, int raw_offset);
|
||
|
||
/* Write PSEUDO_BUF, the contents of a pseudo register, to part of raw register
|
||
RAW_REG_NUM starting at RAW_OFFSET. */
|
||
|
||
void pseudo_to_raw_part (const frame_info_ptr &next_frame,
|
||
gdb::array_view<const gdb_byte> pseudo_buf,
|
||
int raw_reg_num, int raw_offset);
|
||
|
||
/* Create a value for pseudo register PSEUDO_REG_NUM by concatenating raw
|
||
registers RAW_REG_1_NUM and RAW_REG_2_NUM.
|
||
|
||
The sum of the sizes of raw registers must be equal to the size of the
|
||
pseudo register. */
|
||
|
||
value *pseudo_from_concat_raw (const frame_info_ptr &next_frame, int pseudo_reg_num,
|
||
int raw_reg_1_num, int raw_reg_2_num);
|
||
|
||
/* Write PSEUDO_BUF, the contents of a pseudo register, to the two raw registers
|
||
RAW_REG_1_NUM and RAW_REG_2_NUM. */
|
||
|
||
void pseudo_to_concat_raw (const frame_info_ptr &next_frame,
|
||
gdb::array_view<const gdb_byte> pseudo_buf,
|
||
int raw_reg_1_num, int raw_reg_2_num);
|
||
|
||
/* Same as the above, but with three raw registers. */
|
||
|
||
value *pseudo_from_concat_raw (const frame_info_ptr &next_frame, int pseudo_reg_num,
|
||
int raw_reg_1_num, int raw_reg_2_num,
|
||
int raw_reg_3_num);
|
||
|
||
/* Write PSEUDO_BUF, the contents of a pseudo register, to the three raw
|
||
registers RAW_REG_1_NUM, RAW_REG_2_NUM and RAW_REG_3_NUM. */
|
||
|
||
void pseudo_to_concat_raw (const frame_info_ptr &next_frame,
|
||
gdb::array_view<const gdb_byte> pseudo_buf,
|
||
int raw_reg_1_num, int raw_reg_2_num,
|
||
int raw_reg_3_num);
|
||
|
||
#endif /* !defined (VALUE_H) */
|