Remove some checks of .empty()

A few methods in tui_data_window check whether the contents are empty;
but all the callers already check this, so these calls can be removed.

gdb/ChangeLog
2019-08-30  Tom Tromey  <tom@tromey.com>

	* tui/tui-regs.c (tui_data_window::last_regs_line_no)
	(tui_data_window::display_registers_from)
	(tui_data_window::display_reg_element_at_line)
	(tui_data_window::display_registers_from_line): Remove checks of
	"empty".

2 files changed, 104 insertions, 111 deletions

diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index e5f3f21..c8b69f4 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,5 +1,13 @@
 2019-08-30  Tom Tromey  <tom@tromey.com>
 
+	* tui/tui-regs.c (tui_data_window::last_regs_line_no)
+	(tui_data_window::display_registers_from)
+	(tui_data_window::display_reg_element_at_line)
+	(tui_data_window::display_registers_from_line): Remove checks of
+	"empty".
+
+2019-08-30  Tom Tromey  <tom@tromey.com>
+
 	* tui/tui-regs.h (struct tui_data_window) <display_all_data>:
 	Don't declare.
 	* tui/tui-regs.c (tui_data_window::show_registers): Call
diff --git a/gdb/tui/tui-regs.c b/gdb/tui/tui-regs.c
index 7bac19d..636ae10 100644
--- a/gdb/tui/tui-regs.c
+++ b/gdb/tui/tui-regs.c
@@ -98,14 +98,9 @@ tui_get_register (struct frame_info *frame,
 int
 tui_data_window::last_regs_line_no () const
 {
-  int num_lines = (-1);
-
-  if (!regs_content.empty ())
-    {
-      num_lines = regs_content.size () / regs_column_count;
-      if (regs_content.size () % regs_column_count)
-	num_lines++;
-    }
+  int num_lines = regs_content.size () / regs_column_count;
+  if (regs_content.size () % regs_column_count)
+    num_lines++;
   return num_lines;
 }
 
@@ -245,74 +240,71 @@ tui_data_window::show_register_group (struct reggroup *group,
 void
 tui_data_window::display_registers_from (int start_element_no)
 {
-  if (!regs_content.empty ())
+  int j, item_win_width, cur_y;
+
+  int max_len = 0;
+  for (auto &&data_item_win : regs_content)
     {
-      int j, item_win_width, cur_y;
+      const char *p;
+      int len;
 
-      int max_len = 0;
-      for (auto &&data_item_win : regs_content)
-        {
-          const char *p;
-          int len;
-
-          len = 0;
-          p = data_item_win.content.get ();
-          if (p != 0)
-	    len = strlen (p);
-
-          if (len > max_len)
-            max_len = len;
-        }
-      item_win_width = max_len + 1;
-      int i = start_element_no;
-
-      regs_column_count = (width - 2) / item_win_width;
-      if (regs_column_count == 0)
-        regs_column_count = 1;
-      item_win_width = (width - 2) / regs_column_count;
-
-      /* Now create each data "sub" window, and write the display into
-	 it.  */
-      cur_y = 1;
-      while (i < regs_content.size ()
-	     && cur_y <= viewport_height)
+      len = 0;
+      p = data_item_win.content.get ();
+      if (p != 0)
+	len = strlen (p);
+
+      if (len > max_len)
+	max_len = len;
+    }
+  item_win_width = max_len + 1;
+  int i = start_element_no;
+
+  regs_column_count = (width - 2) / item_win_width;
+  if (regs_column_count == 0)
+    regs_column_count = 1;
+  item_win_width = (width - 2) / regs_column_count;
+
+  /* Now create each data "sub" window, and write the display into
+     it.  */
+  cur_y = 1;
+  while (i < regs_content.size ()
+	 && cur_y <= viewport_height)
+    {
+      for (j = 0;
+	   j < regs_column_count && i < regs_content.size ();
+	   j++)
 	{
-	  for (j = 0;
-	       j < regs_column_count && i < regs_content.size ();
-	       j++)
+	  struct tui_data_item_window *data_item_win;
+
+	  /* Create the window if necessary.  */
+	  data_item_win = &regs_content[i];
+	  if (data_item_win->handle != NULL
+	      && (data_item_win->height != 1
+		  || data_item_win->width != item_win_width
+		  || data_item_win->origin.x != (item_win_width * j) + 1
+		  || data_item_win->origin.y != cur_y))
 	    {
-	      struct tui_data_item_window *data_item_win;
-
-	      /* Create the window if necessary.  */
-	      data_item_win = &regs_content[i];
-              if (data_item_win->handle != NULL
-                  && (data_item_win->height != 1
-                      || data_item_win->width != item_win_width
-                      || data_item_win->origin.x != (item_win_width * j) + 1
-                      || data_item_win->origin.y != cur_y))
-                {
-                  tui_delete_win (data_item_win->handle);
-                  data_item_win->handle = 0;
-                }
+	      tui_delete_win (data_item_win->handle);
+	      data_item_win->handle = 0;
+	    }
                   
-	      if (data_item_win->handle == NULL)
-		{
-		  data_item_win->height = 1;
-		  data_item_win->width = item_win_width;
-		  data_item_win->origin.x = (item_win_width * j) + 1;
-		  data_item_win->origin.y = cur_y;
-		  data_item_win->make_visible (true);
-                  scrollok (data_item_win->handle, FALSE);
-		}
-              touchwin (data_item_win->handle);
-
-	      /* Get the printable representation of the register
-                 and display it.  */
-              tui_display_register (data_item_win);
-	      i++;		/* Next register.  */
+	  if (data_item_win->handle == NULL)
+	    {
+	      data_item_win->height = 1;
+	      data_item_win->width = item_win_width;
+	      data_item_win->origin.x = (item_win_width * j) + 1;
+	      data_item_win->origin.y = cur_y;
+	      data_item_win->make_visible (true);
+	      scrollok (data_item_win->handle, FALSE);
 	    }
-	  cur_y++;		/* Next row.  */
+	  touchwin (data_item_win->handle);
+
+	  /* Get the printable representation of the register
+	     and display it.  */
+	  tui_display_register (data_item_win);
+	  i++;		/* Next register.  */
 	}
+      cur_y++;		/* Next row.  */
     }
 }
 
@@ -322,27 +314,24 @@ void
 tui_data_window::display_reg_element_at_line (int start_element_no,
 					      int start_line_no)
 {
-  if (!regs_content.empty ())
-    {
-      int element_no = start_element_no;
+  int element_no = start_element_no;
 
-      if (start_element_no != 0 && start_line_no != 0)
-	{
-	  int last_line_no, first_line_on_last_page;
-
-	  last_line_no = last_regs_line_no ();
-	  first_line_on_last_page = last_line_no - (height - 2);
-	  if (first_line_on_last_page < 0)
-	    first_line_on_last_page = 0;
-
-	  /* If the element_no causes us to scroll past the end of the
-	     registers, adjust what element to really start the
-	     display at.  */
-	  if (start_line_no > first_line_on_last_page)
-	    element_no = first_reg_element_no_inline (first_line_on_last_page);
-	}
-      display_registers_from (element_no);
+  if (start_element_no != 0 && start_line_no != 0)
+    {
+      int last_line_no, first_line_on_last_page;
+
+      last_line_no = last_regs_line_no ();
+      first_line_on_last_page = last_line_no - (height - 2);
+      if (first_line_on_last_page < 0)
+	first_line_on_last_page = 0;
+
+      /* If the element_no causes us to scroll past the end of the
+	 registers, adjust what element to really start the
+	 display at.  */
+      if (start_line_no > first_line_on_last_page)
+	element_no = first_reg_element_no_inline (first_line_on_last_page);
     }
+  display_registers_from (element_no);
 }
 
 /* See tui-regs.h.  */
@@ -351,34 +340,30 @@ int
 tui_data_window::display_registers_from_line (int line_no)
 {
   check_and_display_highlight_if_needed ();
-  if (!regs_content.empty ())
-    {
-      int element_no;
 
-      if (line_no < 0)
-	line_no = 0;
-      else
+  int element_no;
+
+  if (line_no < 0)
+    line_no = 0;
+  else
+    {
+      /* Make sure that we don't display off the end of the
+	 registers.  */
+      if (line_no >= last_regs_line_no ())
 	{
-	  /* Make sure that we don't display off the end of the
-	     registers.  */
-	  if (line_no >= last_regs_line_no ())
-	    {
-	      line_no = line_from_reg_element_no (regs_content.size () - 1);
-	      if (line_no < 0)
-		line_no = 0;
-	    }
+	  line_no = line_from_reg_element_no (regs_content.size () - 1);
+	  if (line_no < 0)
+	    line_no = 0;
 	}
-
-      element_no = first_reg_element_no_inline (line_no);
-      if (element_no < regs_content.size ())
-	display_reg_element_at_line (element_no, line_no);
-      else
-	line_no = (-1);
-
-      return line_no;
     }
 
-  return (-1);			/* Nothing was displayed.  */
+  element_no = first_reg_element_no_inline (line_no);
+  if (element_no < regs_content.size ())
+    display_reg_element_at_line (element_no, line_no);
+  else
+    line_no = (-1);
+
+  return line_no;
 }