binutils-gdb/gdb/utils.h
Luis Machado d88cb738e6 [aarch64] Fix removal of non-address bits for PAuth
PR gdb/28947

The address_significant gdbarch setting was introduced as a way to remove
non-address bits from pointers, and it is specified by a constant.  This
constant represents the number of address bits in a pointer.

Right now AArch64 is the only architecture that uses it, and 56 was a
correct option so far.

But if we are using Pointer Authentication (PAuth), we might use up to 2 bytes
from the address space to store the required information.  We could also have
cases where we're using both PAuth and MTE.

We could adjust the constant to 48 to cover those cases, but this doesn't
cover the case where GDB needs to sign-extend kernel addresses after removal
of the non-address bits.

This has worked so far because bit 55 is used to select between kernel-space
and user-space addresses.  But trying to clear a range of bits crossing the
bit 55 boundary requires the hook to be smarter.

The following patch renames the gdbarch hook from significant_addr_bit to
remove_non_address_bits and passes a pointer as opposed to the number of
bits.  The hook is now responsible for removing the required non-address bits
and sign-extending the address if needed.

While at it, make GDB and GDBServer share some more code for aarch64 and add a
new arch-specific testcase gdb.arch/aarch64-non-address-bits.exp.

Bug-url: https://sourceware.org/bugzilla/show_bug.cgi?id=28947

Approved-By: Simon Marchi <simon.marchi@efficios.com>
2022-12-16 11:18:32 +00:00

367 lines
12 KiB
C++
Raw Blame History

This file contains invisible Unicode characters

This file contains invisible Unicode characters that are indistinguishable to humans but may be processed differently by a computer. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

/* *INDENT-OFF* */ /* ATTRIBUTE_PRINTF confuses indent, avoid running it
for now. */
/* I/O, string, cleanup, and other random utilities for GDB.
Copyright (C) 1986-2022 Free Software Foundation, Inc.
This file is part of GDB.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>. */
#ifndef UTILS_H
#define UTILS_H
#include "exceptions.h"
#include "gdbsupport/array-view.h"
#include "gdbsupport/scoped_restore.h"
#include <chrono>
#ifdef HAVE_LIBXXHASH
#include <xxhash.h>
#endif
struct completion_match_for_lcd;
class compiled_regex;
/* String utilities. */
extern bool sevenbit_strings;
/* Modes of operation for strncmp_iw_with_mode. */
enum class strncmp_iw_mode
{
/* Do a strcmp() type operation on STRING1 and STRING2, ignoring any
differences in whitespace. Returns 0 if they match, non-zero if
they don't (slightly different than strcmp()'s range of return
values). */
NORMAL,
/* Like NORMAL, but also apply the strcmp_iw hack. I.e.,
string1=="FOO(PARAMS)" matches string2=="FOO". */
MATCH_PARAMS,
};
/* Helper for strcmp_iw and strncmp_iw. Exported so that languages
can implement both NORMAL and MATCH_PARAMS variants in a single
function and defer part of the work to strncmp_iw_with_mode.
LANGUAGE is used to implement some context-sensitive
language-specific comparisons. For example, for C++,
"string1=operator()" should not match "string2=operator" even in
MATCH_PARAMS mode.
MATCH_FOR_LCD is passed down so that the function can mark parts of
the symbol name as ignored for completion matching purposes (e.g.,
to handle abi tags). If IGNORE_TEMPLATE_PARAMS is true, all template
parameter lists will be ignored when language is C++. */
extern int strncmp_iw_with_mode
(const char *string1, const char *string2, size_t string2_len,
strncmp_iw_mode mode, enum language language,
completion_match_for_lcd *match_for_lcd = NULL,
bool ignore_template_params = false);
/* Do a strncmp() type operation on STRING1 and STRING2, ignoring any
differences in whitespace. STRING2_LEN is STRING2's length.
Returns 0 if STRING1 matches STRING2_LEN characters of STRING2,
non-zero otherwise (slightly different than strncmp()'s range of
return values). Note: passes language_minimal to
strncmp_iw_with_mode, and should therefore be avoided if a more
suitable language is available. */
extern int strncmp_iw (const char *string1, const char *string2,
size_t string2_len);
/* Do a strcmp() type operation on STRING1 and STRING2, ignoring any
differences in whitespace. Returns 0 if they match, non-zero if
they don't (slightly different than strcmp()'s range of return
values).
As an extra hack, string1=="FOO(ARGS)" matches string2=="FOO".
This "feature" is useful when searching for matching C++ function
names (such as if the user types 'break FOO', where FOO is a
mangled C++ function).
Note: passes language_minimal to strncmp_iw_with_mode, and should
therefore be avoided if a more suitable language is available. */
extern int strcmp_iw (const char *string1, const char *string2);
extern int strcmp_iw_ordered (const char *, const char *);
/* Reset the prompt_for_continue clock. */
void reset_prompt_for_continue_wait_time (void);
/* Return the time spent in prompt_for_continue. */
std::chrono::steady_clock::duration get_prompt_for_continue_wait_time ();
/* Parsing utilities. */
extern int parse_pid_to_attach (const char *args);
extern int parse_escape (struct gdbarch *, const char **);
/* Cleanup utilities. */
extern void init_page_info (void);
/* Temporarily set BATCH_FLAG and the associated unlimited terminal size.
Restore when destroyed. */
struct set_batch_flag_and_restore_page_info
{
public:
set_batch_flag_and_restore_page_info ();
~set_batch_flag_and_restore_page_info ();
DISABLE_COPY_AND_ASSIGN (set_batch_flag_and_restore_page_info);
private:
/* Note that this doesn't use scoped_restore, because it's important
to control the ordering of operations in the destruction, and it
was simpler to avoid introducing a new ad hoc class. */
unsigned m_save_lines_per_page;
unsigned m_save_chars_per_line;
int m_save_batch_flag;
};
/* Path utilities. */
extern int gdb_filename_fnmatch (const char *pattern, const char *string,
int flags);
extern void substitute_path_component (char **stringp, const char *from,
const char *to);
std::string ldirname (const char *filename);
extern int count_path_elements (const char *path);
extern const char *strip_leading_path_elements (const char *path, int n);
/* GDB output, ui_file utilities. */
struct ui_file;
extern int query (const char *, ...) ATTRIBUTE_PRINTF (1, 2);
extern int nquery (const char *, ...) ATTRIBUTE_PRINTF (1, 2);
extern int yquery (const char *, ...) ATTRIBUTE_PRINTF (1, 2);
extern void begin_line (void);
extern void wrap_here (int);
extern void reinitialize_more_filter (void);
/* Return the number of characters in a line. */
extern int get_chars_per_line ();
extern bool pagination_enabled;
/* A flag indicating whether to timestamp debugging messages. */
extern bool debug_timestamp;
extern struct ui_file **current_ui_gdb_stdout_ptr (void);
extern struct ui_file **current_ui_gdb_stdin_ptr (void);
extern struct ui_file **current_ui_gdb_stderr_ptr (void);
extern struct ui_file **current_ui_gdb_stdlog_ptr (void);
/* Flush STREAM. */
extern void gdb_flush (struct ui_file *stream);
/* The current top level's ui_file streams. */
/* Normal results */
#define gdb_stdout (*current_ui_gdb_stdout_ptr ())
/* Input stream */
#define gdb_stdin (*current_ui_gdb_stdin_ptr ())
/* Serious error notifications. This bypasses the pager, if one is in
use. */
#define gdb_stderr (*current_ui_gdb_stderr_ptr ())
/* Log/debug/trace messages that bypasses the pager, if one is in
use. */
#define gdb_stdlog (*current_ui_gdb_stdlog_ptr ())
/* Truly global ui_file streams. These are all defined in main.c. */
/* Target output that should bypass the pager, if one is in use. */
extern struct ui_file *gdb_stdtarg;
extern struct ui_file *gdb_stdtargerr;
extern struct ui_file *gdb_stdtargin;
/* Set the screen dimensions to WIDTH and HEIGHT. */
extern void set_screen_width_and_height (int width, int height);
/* Generic stdio-like operations. */
extern void gdb_puts (const char *, struct ui_file *);
extern void gdb_putc (int c, struct ui_file *);
extern void gdb_putc (int c);
extern void gdb_puts (const char *);
extern void puts_tabular (char *string, int width, int right);
/* Generic printf-like operations. As an extension over plain
printf, these support some GDB-specific format specifiers.
Particularly useful here are the styling formatters: '%p[', '%p]'
and '%ps'. See ui_out::message for details. */
extern void gdb_vprintf (const char *, va_list) ATTRIBUTE_PRINTF (1, 0);
extern void gdb_vprintf (struct ui_file *, const char *, va_list)
ATTRIBUTE_PRINTF (2, 0);
extern void gdb_printf (struct ui_file *, const char *, ...)
ATTRIBUTE_PRINTF (2, 3);
extern void gdb_printf (const char *, ...) ATTRIBUTE_PRINTF (1, 2);
extern void printf_unfiltered (const char *, ...) ATTRIBUTE_PRINTF (1, 2);
extern void print_spaces (int, struct ui_file *);
extern const char *n_spaces (int);
/* Return nonzero if filtered printing is initialized. */
extern int filtered_printing_initialized (void);
/* Like gdb_printf, but styles the output according to STYLE,
when appropriate. */
extern void fprintf_styled (struct ui_file *stream,
const ui_file_style &style,
const char *fmt,
...)
ATTRIBUTE_PRINTF (3, 4);
/* Like gdb_puts, but styles the output according to STYLE, when
appropriate. */
extern void fputs_styled (const char *linebuffer,
const ui_file_style &style,
struct ui_file *stream);
/* Like fputs_styled, but uses highlight_style to highlight the
parts of STR that match HIGHLIGHT. */
extern void fputs_highlighted (const char *str, const compiled_regex &highlight,
struct ui_file *stream);
/* Convert CORE_ADDR to string in platform-specific manner.
This is usually formatted similar to 0x%lx. */
extern const char *paddress (struct gdbarch *gdbarch, CORE_ADDR addr);
/* Return a string representation in hexadecimal notation of ADDRESS,
which is suitable for printing. */
extern const char *print_core_address (struct gdbarch *gdbarch,
CORE_ADDR address);
extern CORE_ADDR string_to_core_addr (const char *my_string);
extern void fprintf_symbol (struct ui_file *, const char *,
enum language, int);
extern void perror_warning_with_name (const char *string);
extern void print_sys_errmsg (const char *, int);
/* Warnings and error messages. */
extern void (*deprecated_error_begin_hook) (void);
/* Message to be printed before the warning message, when a warning occurs. */
extern const char *warning_pre_print;
extern void error_stream (const string_file &) ATTRIBUTE_NORETURN;
extern void demangler_vwarning (const char *file, int line,
const char *, va_list ap)
ATTRIBUTE_PRINTF (3, 0);
extern void demangler_warning (const char *file, int line,
const char *, ...) ATTRIBUTE_PRINTF (3, 4);
/* Misc. utilities. */
#ifdef HAVE_WAITPID
extern pid_t wait_to_die_with_timeout (pid_t pid, int *status, int timeout);
#endif
extern int myread (int, char *, int);
/* Integer exponentiation: Return V1**V2, where both arguments
are integers.
Requires V1 != 0 if V2 < 0.
Returns 1 for 0 ** 0. */
extern ULONGEST uinteger_pow (ULONGEST v1, LONGEST v2);
/* Resource limits used by getrlimit and setrlimit. */
enum resource_limit_kind
{
LIMIT_CUR,
LIMIT_MAX
};
/* Check whether GDB will be able to dump core using the dump_core
function. Returns zero if GDB cannot or should not dump core.
If LIMIT_KIND is LIMIT_CUR the user's soft limit will be respected.
If LIMIT_KIND is LIMIT_MAX only the hard limit will be respected. */
extern int can_dump_core (enum resource_limit_kind limit_kind);
/* Print a warning that we cannot dump core. */
extern void warn_cant_dump_core (const char *reason);
/* Dump core trying to increase the core soft limit to hard limit
first. */
extern void dump_core (void);
/* Copy NBITS bits from SOURCE to DEST starting at the given bit
offsets. Use the bit order as specified by BITS_BIG_ENDIAN.
Source and destination buffers must not overlap. */
extern void copy_bitwise (gdb_byte *dest, ULONGEST dest_offset,
const gdb_byte *source, ULONGEST source_offset,
ULONGEST nbits, int bits_big_endian);
/* A fast hashing function. This can be used to hash data in a fast way
when the length is known. If no fast hashing library is available, falls
back to iterative_hash from libiberty. START_VALUE can be set to
continue hashing from a previous value. */
static inline unsigned int
fast_hash (const void *ptr, size_t len, unsigned int start_value = 0)
{
#ifdef HAVE_LIBXXHASH
return XXH64 (ptr, len, start_value);
#else
return iterative_hash (ptr, len, start_value);
#endif
}
#endif /* UTILS_H */