noalias for functions?

I'm looking for a way to mark a function that may read and/or write to it's pointer arguments but that does not read or write to any other memory. Is there a combination of attributes that makes this possible? The best I can find is the readnone/readonly and noalias attributes, but it doesn't seem to be possible to indicate that it's only the pointer arguments that are read or modified (and not all the other global state).

Here's a reference to a visual studio attribute that is essentially what I want:

http://msdn.microsoft.com/en-us/library/k649tyc7(v=vs.80).aspx

Andrew