What is the difference between register windows in Itanium and SPARC?

Question

Iron

The Itanium and SPARC processors have a mechanism for working with register windows.
Question: what are the differences in the implementation of these mechanisms in these architectures?
Thanks in advance!

Answer 1

Itanuim has a fixed number of 128 registers. 32 of them are static, and the rest are dynamic under register windows. In SPARC, register windows are a classic vendor-implementation drum and only give the programmer 31 logical registers (+ register zero) at his disposal. And physical registers there can easily reach up to several hundred. The MSCT R500 has 132 physical registers, as I recall. But a small number of register-windows can be allocated. That is, for SPARC, you can optimize the architecture for specific tasks, where the stored data can not be immediately driven into RAM, when programs with different call depths and stacks work.