The closest facility is the 'info vector' command, which by default prints the contents of all vector registers, but is documented simply as "Print the status of the vector unit.", which I take to mean that it can be overridden to have arch-specific output, much like 'info float'. An 'info vector-registers' and 'info fp-registers' command might not be such a bad idea, but none exists at the moment that I know of.
The wording was lifted from ``info float''. The assumption is that the
architecture backend will eventually find it necessary customize these
commands. For the architectures I've looked at (Intel's SSE and WMMX)
an ``info vector'' command ends up needing to print both true vector
registers and some associated status registers. The (er now legendary)
reggroups code addresses much of this problem.