Author: Daniel Lemire - Page 3

Apple’s M1 processor and the full 128-bit integer product

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2025-12-302021-03-18 by Daniel Lemire

If I multiply two 64-bit integers (having values in [0, 264)), the product requires 128 bits. Intel and AMD processors (x64) can compute the full (128-bit) product of two 64-bit integers using a single instruction (mul). ARM processors, such as those … Read more

How does your programming language handle “minus zero” (-0.0)?

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2025-12-302021-03-05 by Daniel Lemire

how-does-your-programming-language-handle-“minus-zero”-(-0.0)?

The ubiquitous IEEE floating-point standard defines two numbers to represent zero, the positive and the negative zeros. You also have the positive and negative infinity. If you compute the inverse of the positive zero, you get the positive infinity. If … Read more