Add new command line option -singlestep for tcg single stepping.

This replaces a compile time option for some targets and adds
this feature to targets which did not have a compile time option.

Add monitor command to enable or disable single step mode.

Modify monitor command "info status" to display single step mode.

Signed-off-by: Stefan Weil <weil@mail.berlios.de>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>

git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@7004 c046a42c-6fe2-441c-8c8c-71466251a162
diff --git a/qemu-doc.texi b/qemu-doc.texi
index 61a08ee..3742b45 100644
--- a/qemu-doc.texi
+++ b/qemu-doc.texi
@@ -490,6 +490,10 @@
 @item delvm @var{tag}|@var{id}
 Delete the snapshot identified by @var{tag} or @var{id}.
 
+@item singlestep [off]
+Run the emulation in single step mode.
+If called with option off, the emulation returns to normal mode.
+
 @item stop
 Stop emulation.
 
@@ -2370,6 +2374,8 @@
 Act as if the host page size was 'pagesize' bytes
 @item -g port
 Wait gdb connection to port
+@item -singlestep
+Run the emulation in single step mode.
 @end table
 
 Environment variables:
@@ -2488,6 +2494,8 @@
 Activate log (logfile=/tmp/qemu.log)
 @item -p pagesize
 Act as if the host page size was 'pagesize' bytes
+@item -singlestep
+Run the emulation in single step mode.
 @end table
 
 @node BSD User space emulator
@@ -2550,6 +2558,8 @@
 Activate log (logfile=/tmp/qemu.log)
 @item -p pagesize
 Act as if the host page size was 'pagesize' bytes
+@item -singlestep
+Run the emulation in single step mode.
 @end table
 
 @node compilation