The whole impact of the architecture on the processor is to be considered, not just the size of the decoder. If the ISA was irrelevant (and the ISA does not jus

The whole impact of the architecture on the processor is to be considered, not just the size of the decoder. If the ISA was irrelevant (and the ISA does not just influence the decoder, it influences pretty much everything in various degrees) in modern days and even semi-modern days, Intel, with all its power (vastly superior to Arm, from a financing pov), would have come with something that does not suck in mobiles given how strategic this market is. It has not. In other words, you should not confuse the size of the lexicon with its associated comprehensive semantics. It does not matter that adding instructions in that framework is not too costly. The framework itself is costly for some applications...