There's a ton of innovation happening right now for machine-learning optimized ISAs. And RISC-V has excellent support for extensions.
The funniest part of Itanium for me was that it was supposedly helpful to compilers. Yet the compiler people I knew did not like to use the "helpful" parts of the ISA. The loop unrolling stuff got in the way of software pipelining, for example.
Mill is an example of a processor that's actually helpful to compilers, because its design is being led by an actual compiler person.
The funniest part of Itanium for me was that it was supposedly helpful to compilers. Yet the compiler people I knew did not like to use the "helpful" parts of the ISA. The loop unrolling stuff got in the way of software pipelining, for example.
Mill is an example of a processor that's actually helpful to compilers, because its design is being led by an actual compiler person.