> VLIW is not binary forward- or cross-implementation-compatible.
It was on IA-64, the bundle format was deliberately chosen to allow for easy extension.
But broadly it's true: you can't have a "pure" VLIW architecture independent of the issue and pipeline architecture of the CPU. Any device with differing runtime architecture is going to have to do some cooking of the instructions to match it to its own backend. But that decode engine is much easier to write when it's starting from a wide format that presents lots of instructions and makes explicit promises about their interdependencies.
It was on IA-64, the bundle format was deliberately chosen to allow for easy extension.
But broadly it's true: you can't have a "pure" VLIW architecture independent of the issue and pipeline architecture of the CPU. Any device with differing runtime architecture is going to have to do some cooking of the instructions to match it to its own backend. But that decode engine is much easier to write when it's starting from a wide format that presents lots of instructions and makes explicit promises about their interdependencies.