misc: dot_writer fixup

In large configs the tooltip may be greater then the maximum line
size graphviz supports when parsing the dot file (typically 16k).
Adding '/' causes graphviz to break the string in multiple lines
while parsing and works around this limitation.

Change-Id: I16a0030127de4165080de97f5213309eed9fdeca
Signed-off-by: Tiago Mück <tiago.muck@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/19208
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Jason Lowe-Power <jason@lowepower.com>
Tested-by: kokoro <noreply+kokoro@google.com>

src/python/m5/util/dot_writer.py

@@ -1,4 +1,4 @@
-# Copyright (c) 2012-2013 ARM Limited
+# Copyright (c) 2012-2013,2019 ARM Limited
 # All rights reserved.
 #
 # The license below extends only to copyright in the software and shall
@@ -154,7 +154,7 @@ def dot_create_cluster(simNode, full_path, label):
             ini_strings.append(str(param) + "=" +
                                simNode._values[param].ini_str())
     # join all the parameters with an HTML newline
-    tooltip = "
".join(ini_strings)
+    tooltip = "
\\".join(ini_strings)
 
     return pydot.Cluster( \
                          full_path, \