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[gdb/tui] Use const std::string for string literals in tui-stack.c

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I noticed in gdb/tui/tui-stack.c a source-level micro-optimization where
strlen with a string literal argument:
...
strlen ("bla")
...
is replaced with sizeof:
...
sizeof ("bla") - 1
...

The benefit of this is that the optimization is also done at O0, but the
drawback is that it makes the expression harder to read.

Use const std::string to encapsulate the string literals, and use
std::string::size () instead.

I tried making the string names (PROC_PREFIX, LINE_PREFIX, PC_PREFIX and
SINGLE_KEY) lower-case, but that clashed with a pre-existing pc_prefix, so
I've left them upper-case.

Tested on x86_64-linux.

Tested-By: Alexandra Petlanova Hajkova <ahajkova@redhat.com>
This commit is contained in:
Tom de Vries 2023-11-28 16:31:07 +01:00
parent 9d4db627b2
commit 1f6ce80388
1 changed files with 16 additions and 17 deletions
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33
gdb/tui/tui-stack.c
View File

@ -40,12 +40,12 @@
#include "gdb_curses.h"
#define PROC_PREFIX "In: "
#define LINE_PREFIX "L"
#define PC_PREFIX "PC: "
static const std::string PROC_PREFIX = "In: ";
static const std::string LINE_PREFIX = "L";
static const std::string PC_PREFIX = "PC: ";
/* Strings to display in the TUI status line. */
#define SINGLE_KEY "(SingleKey)"
static const std::string SINGLE_KEY = "(SingleKey)";
/* Minimum/Maximum length of some fields displayed in the TUI status
line. */
@ -107,16 +107,15 @@ tui_locator_window::make_status_line () const
int pc_width = pc_out.size ();
/* First determine the amount of proc name width we have available.
The +1 are for a space separator between fields.
The -1 are to take into account the \0 counted by sizeof. */
The +1 are for a space separator between fields. */
proc_width = (status_size
- (target_width + 1)
- (pid_width + 1)
- (sizeof (PROC_PREFIX) - 1 + 1)
- (sizeof (LINE_PREFIX) - 1 + line_width + 1)
- (sizeof (PC_PREFIX) - 1 + pc_width + 1)
- (PROC_PREFIX.size () + 1)
- (LINE_PREFIX.size () + line_width + 1)
- (PC_PREFIX.size () + pc_width + 1)
- (tui_current_key_mode == TUI_SINGLE_KEY_MODE
? (sizeof (SINGLE_KEY) - 1 + 1)
? (SINGLE_KEY.size () + 1)
: 0));
/* If there is no room to print the function name, try by removing
@ -131,11 +130,11 @@ tui_locator_window::make_status_line () const
pid_width = 0;
if (proc_width <= MIN_PROC_WIDTH)
{
proc_width += pc_width + sizeof (PC_PREFIX) - 1 + 1;
proc_width += pc_width + PC_PREFIX.size () + 1;
pc_width = 0;
if (proc_width < 0)
{
proc_width += line_width + sizeof (LINE_PREFIX) - 1 + 1;
proc_width += line_width + LINE_PREFIX.size () + 1;
line_width = 0;
if (proc_width < 0)
proc_width = 0;
@ -156,7 +155,7 @@ tui_locator_window::make_status_line () const
/* Show whether we are in SingleKey mode. */
if (tui_current_key_mode == TUI_SINGLE_KEY_MODE)
{
string.puts (SINGLE_KEY);
string.puts (SINGLE_KEY.c_str ());
string.puts (" ");
}
@ -165,19 +164,19 @@ tui_locator_window::make_status_line () const
{
const std::string &proc_name = tui_location.proc_name ();
if (proc_name.size () > proc_width)
string.printf ("%s%*.*s* ", PROC_PREFIX,
string.printf ("%s%*.*s* ", PROC_PREFIX.c_str (),
1 - proc_width, proc_width - 1, proc_name.c_str ());
else
string.printf ("%s%*.*s ", PROC_PREFIX,
string.printf ("%s%*.*s ", PROC_PREFIX.c_str (),
-proc_width, proc_width, proc_name.c_str ());
}
if (line_width > 0)
string.printf ("%s%*.*s ", LINE_PREFIX,
string.printf ("%s%*.*s ", LINE_PREFIX.c_str (),
-line_width, line_width, line_buf);
if (pc_width > 0)
{
string.puts (PC_PREFIX);
string.puts (PC_PREFIX.c_str ());
string.puts (pc_buf);
}