[snvzz]

>Even Intel thought that CISC was on the way out, although they were going down a somewhat extreme path with EPIC, but the most successful approach turned out to be a hybrid where complex CISC instructions were broken into RISC-like micro-ops.

Note that neither are these micro-ops RISC (they are long, complex and specific to the chip, actually much closer to EPIC), nor was this micro-ops approach new.

Intel tried to use the 64 bit transition to finally abandon x86.

It almost managed to do this, but AMD saw a chance and AMD64 happened, ironically leveraging the x86 software moat against Intel. Software would not migrate to Itanium, but smoothly transition to AMD64.

Without the moat, Itanium was doomed. But it was doomed either way, as was found later, due to its complexity. Complicating compilers, having learned nothing from the RISC paper.

[acdha]

> Note that neither are these micro-ops RISC (they are long, complex and specific to the chip, actually much closer to EPIC), nor was this micro-ops approach new.

I was mostly thinking about them as simpler - which is not the same as simple - but mostly in the larger context of it not being a religion where chip designers pick a side and never budge, when in reality everyone finds ways to use good ideas that make sense for their designs.

[snvzz]

>mostly in the larger context of it not being a religion where chip designers pick a side and never budge, when in reality everyone finds ways to use good ideas that make sense for their designs.

Chip designers design chips (I suspect you meant to emphasize microarchitectures), whereas ISA designers design ISAs.

An ISA designer's concern is to design a good ISA[0]. A good ISA will be chosen and loved by microarchitecture designers. This enthusiasm might then come off as religion-like.

0. https://news.ycombinator.com/item?id=39848530