The radix 2^51 trick

Re:The radix 2^51 trick by nickdothutton on Tuesday November 22, 2022 @04:55PM (#33712085)

The sort of operation familiar to Z80 programmers back in the day.

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Re:The radix 2^51 trick by bsder on Tuesday November 22, 2022 @07:11PM (#33713346)

I don't think that's true.

ADC (add with carry) was just fine on the 8080, Z80, 6502, 6800 generation sicne memory was the same speed as CPU and everything executed in a single cycle. I mean, you even had instructions like DAA (Decimal Adjust Accumulator) which were just fine for doing BCD arithmetic.

You only benefit from tricks like these when you get wide dispatch, speculative execution processors.

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