As in, 8 bit 8085 had 28 possible instructions, 32 bit ones had 232 and already had enough possible combinations that we couldn’t come up with enough functions to fill the provided space.
I don’t think that works though. For something like RISC-V, RV64 has a maximum 32-bit instruction encoding. For x86-64 those original 8-bit intructions still exist, and take up a huge part of the encoding space, cutting the number of n-bit instructions to more like 2^(n-7)
I kinda expected that to happen, since there’s already enough to fit all required functions. So yeah, even this is not a good enough criteria for bit rating.
those original 8-bit intructions still exist, and take up a huge part of the encoding space, cutting the number of n-bit instructions to more like 2^(n-7)
err… they are still instructions, right? And they are implemented. I don’t see why you would negate that from the number of instructions.
I see it as the number of possible instructions.
As in, 8 bit 8085 had 28 possible instructions, 32 bit ones had 232 and already had enough possible combinations that we couldn’t come up with enough functions to fill the provided space.
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So “instruction encoding length”.
I don’t think that works though. For something like RISC-V, RV64 has a maximum 32-bit instruction encoding. For x86-64 those original 8-bit intructions still exist, and take up a huge part of the encoding space, cutting the number of n-bit instructions to more like 2^(n-7)
I kinda expected that to happen, since there’s already enough to fit all required functions. So yeah, even this is not a good enough criteria for bit rating.
err… they are still instructions, right? And they are implemented. I don’t see why you would negate that from the number of instructions.