Add rtx-classes-status.txt

2014-08-18  David Malcolm  <dmalcolm@redhat.com>

        * rtx-classes-status.txt: New file

From-SVN: r214116

ChangeLog

+2014-08-18  David Malcolm  <dmalcolm@redhat.com>
+
+        * rtx-classes-status.txt: New file
+
 2014-08-18 Roman Gareev  <gareevroman@gmail.com>
 
 	* configure.ac: Eliminate ClooG installation dependency.

rtx-classes-status.txt

+This file tracks the status of the merger of the
+"Introduce rtx subclasses" patches, and is slated for removal once all
+are merged.
+
+See https://gcc.gnu.org/ml/gcc-patches/2014-08/msg00498.html for more
+information.
+
+Phase 1: initial "scaffolding" commits:            IN PROGRESS
+Phase 2: per-file commits in main source dir:      TODO
+Phase 3: per-file commits within "config" subdirs: TODO
+Phase 4: removal of "scaffolding":                 TODO
+Phase 5: additional rtx_def subclasses:            TODO
+Phase 6: use extra rtx_def subclasses:             TODO