I just committed a little binary analysis tool to moxiedev. You can use it to perform simple static analysis on moxie binaries. The kinds of things I'm looking for are compiler bugs (because I know there's still one there that is triggered by -frerun-cse-after-loop), and instruction statistics. For instance, which registers are used as load offsets, and how often? The tool uses a primitive plugin architecture that should make it easy to add new analysis tools in the future. It's called the moxielyzer, and here is the initial commit. Run it with no arguments to get a list of plugins. Run it with just a plugin name, and it will describe the plugin. Run it with a plugin name as well as an ELF moxie executable filename, and the analysis will be performed.
I had written a similar tool for ggx back in the bad old days. Another option was to hack this stuff into gas, but I prefer to keep gas "clean" (translation: I want the freedom to maintain hacky analysis code).
BTW - I'm also rolling out a new libffi in a few weeks. You can keep track of the release candidate test results on the wiki here.