• @Malfeasant@lemm.ee
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    011 days ago

    Yes, but it’s not universal that xoring a register with itself is more performant than simply loading it with 0.

        • Q*Bert Reynolds
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          110 days ago

          No argument there. It’s also why it’s done in ARM, 8080, SM83, z80, 6502, and basically every other assembly language. It’s only not done in RISC-V because you can fold 0 into any instruction as an operand, therefore eliminating the need to clear a register before an instruction.

          So why correct the person with a more narrow claim that makes it seem like xor being faster than loading zero is a rarity in CPU architectures? If I said “birds can fly”, and your response was “eagles can fly. Ftfy. Not all birds can fly”, it would be both true and utterly unhelpful.