One Instruction Set Computer

Re:One Instruction Set Computer by excessive on Sunday December 08, 2019 @02:41AM (#21734785)

x86's version of a single "instruction" is frequently a large class of opcodes. It's kind of crazy considering the assembler chooses one of the following numbers for "mov" based on the operand types, not the mnemonic:

    88, 89, 8A, 8B, 8C, 8E, A0, A1, A2, A3, B0, B8, C6, C7

This also ignores all of the prefix bytes.

https://www.felixcloutier.com/x86/mov

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Re:One Instruction Set Computer by mike_hock on Sunday December 08, 2019 @06:49AM (#21735458)

Also, MOV is far from only a bit copy. It's (potentially, depending on the operands), left shift, add, load, store.

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