[COMMIT PATCH] record-full.c: Remove always true checks.

[Pedro Alves <palves at redhat dot com>]

The "set record full insn-number-max" command is an uinteger command.
If the variable that holds the maximum count of logged instructions is
unsigned, it's better if the variable that holds the current number of
logged instructions is also unsigned.  Looking over the code, there's
no case the variable could end up negative.

Then, tests like "if (record_full_insn_max_num)" are always true,
because being a uinteger command means that "set record full
insn-number-max 0" is actually mapped to UINT_MAX internally.  IOW,
the command's variable is never 0.  The checks might make some sense
if 0 wasn't mapped to UINT_MAX, and 0 meant unlimited, but, that's not
how things work.

Tested on x86_64 Fedora 17.

gdb/
2013-03-26  Pedro Alves  <palves@redhat.com>

	* record-full.c (record_full_insn_num): Make it unsigned.
	(record_full_check_insn_num, record_full_message)
	(record_full_registers_change, record_full_xfer_partial): Remove
	record_full_insn_max_num check (it's always != 0).
	(record_full_info, record_full_restore): Use %u as format string.
	(): Use %u as format string.
	(set_record_full_insn_max_num): Remove record_full_insn_max_num
	check (it's always != 0).
---
 gdb/record-full.c |   56 +++++++++++++++++++++++------------------------------
 1 file changed, 24 insertions(+), 32 deletions(-)

diff --git a/gdb/record-full.c b/gdb/record-full.c
index 23b8833..2ff7dec 100644
--- a/gdb/record-full.c
+++ b/gdb/record-full.c
@@ -199,7 +199,7 @@ static int record_full_stop_at_limit = 1;
 static unsigned int record_full_insn_max_num
 	= DEFAULT_RECORD_FULL_INSN_MAX_NUM;
 /* Actual count of insns presently in execution log.  */
-static int record_full_insn_num = 0;
+static unsigned int record_full_insn_num = 0;
 /* Count of insns logged so far (may be larger
    than count of insns presently in execution log).  */
 static ULONGEST record_full_insn_count;
@@ -557,28 +557,24 @@ record_full_arch_list_add_end (void)
 static void
 record_full_check_insn_num (int set_terminal)
 {
-  if (record_full_insn_max_num)
+  if (record_full_insn_num == record_full_insn_max_num)
     {
-      gdb_assert (record_full_insn_num <= record_full_insn_max_num);
-      if (record_full_insn_num == record_full_insn_max_num)
+      /* Ask user what to do.  */
+      if (record_full_stop_at_limit)
 	{
-	  /* Ask user what to do.  */
-	  if (record_full_stop_at_limit)
-	    {
-	      int q;
-
-	      if (set_terminal)
-		target_terminal_ours ();
-	      q = yquery (_("Do you want to auto delete previous execution "
-			    "log entries when record/replay buffer becomes "
-			    "full (record full stop-at-limit)?"));
-	      if (set_terminal)
-		target_terminal_inferior ();
-	      if (q)
-		record_full_stop_at_limit = 0;
-	      else
-		error (_("Process record: stopped by user."));
-	    }
+	  int q;
+
+	  if (set_terminal)
+	    target_terminal_ours ();
+	  q = yquery (_("Do you want to auto delete previous execution "
+			"log entries when record/replay buffer becomes "
+			"full (record full stop-at-limit)?"));
+	  if (set_terminal)
+	    target_terminal_inferior ();
+	  if (q)
+	    record_full_stop_at_limit = 0;
+	  else
+	    error (_("Process record: stopped by user."));
 	}
     }
 }
@@ -659,8 +655,7 @@ record_full_message (struct regcache *regcache, enum gdb_signal signal)
   record_full_arch_list_head->prev = record_full_list;
   record_full_list = record_full_arch_list_tail;
 
-  if (record_full_insn_num == record_full_insn_max_num
-      && record_full_insn_max_num)
+  if (record_full_insn_num == record_full_insn_max_num)
     record_full_list_release_first ();
   else
     record_full_insn_num++;
@@ -1573,8 +1568,7 @@ record_full_registers_change (struct regcache *regcache, int regnum)
   record_full_arch_list_head->prev = record_full_list;
   record_full_list = record_full_arch_list_tail;
 
-  if (record_full_insn_num == record_full_insn_max_num
-      && record_full_insn_max_num)
+  if (record_full_insn_num == record_full_insn_max_num)
     record_full_list_release_first ();
   else
     record_full_insn_num++;
@@ -1693,8 +1687,7 @@ record_full_xfer_partial (struct target_ops *ops, enum target_object object,
       record_full_arch_list_head->prev = record_full_list;
       record_full_list = record_full_arch_list_tail;
 
-      if (record_full_insn_num == record_full_insn_max_num
-	  && record_full_insn_max_num)
+      if (record_full_insn_num == record_full_insn_max_num)
 	record_full_list_release_first ();
       else
 	record_full_insn_num++;
@@ -1958,14 +1951,14 @@ record_full_info (void)
 		       pulongest (record_full_insn_count));
 
       /* Display log count.  */
-      printf_filtered (_("Log contains %d instructions.\n"),
+      printf_filtered (_("Log contains %u instructions.\n"),
 		       record_full_insn_num);
     }
   else
     printf_filtered (_("No instructions have been logged.\n"));
 
   /* Display max log size.  */
-  printf_filtered (_("Max logged instructions is %d.\n"),
+  printf_filtered (_("Max logged instructions is %u.\n"),
 		   record_full_insn_max_num);
 }
 
@@ -2586,7 +2579,7 @@ record_full_restore (void)
   if (record_full_insn_num > record_full_insn_max_num)
     {
       record_full_insn_max_num = record_full_insn_num;
-      warning (_("Auto increase record/replay buffer limit to %d."),
+      warning (_("Auto increase record/replay buffer limit to %u."),
                record_full_insn_max_num);
     }
 
@@ -2880,8 +2873,7 @@ static void
 set_record_full_insn_max_num (char *args, int from_tty,
 			      struct cmd_list_element *c)
 {
-  if (record_full_insn_num > record_full_insn_max_num
-      && record_full_insn_max_num)
+  if (record_full_insn_num > record_full_insn_max_num)
     {
       /* Count down record_full_insn_num while releasing records from list.  */
       while (record_full_insn_num > record_full_insn_max_num)