Sparc and Xtensa also have register windows, although each has a slightly different implementation.
They were all the rage for a while, because they make procedure calls fast but turn out to have subtle issues in highly-multithreaded scenarios.
The Sparc and Xtensa register windows are fixed-size, not dynamic like Itanium's.
The Sparc and Xtensa register windows are fixed-size, not dynamic like Itanium's.