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Which integer division algorithm does Intel implement in their x86 processors?

Peter Cordes
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n0p
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    There have been an awful lot of different x86 processors designed by many different companies in the last 30 years or so. Do you really imagine every single one of them implements integer division in the same way? – talonmies Dec 06 '11 at 14:11
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    yes, i thought that the most of processors designed by intel last several years have the same integer division algorithm. Maybe i'm wrong, i have no idea. But it makes no sense, we can talk about Pentium (1,2,3,4). The more the better. – n0p Dec 06 '11 at 14:20
  • Related: [How sqrt() of GCC works after compiled? Which method of root is used? Newton-Raphson?](//stackoverflow.com/q/54642663) has some details of how FP div/sqrt execution units are built, with a link to a paper about one on-paper design. – Peter Cordes Oct 16 '19 at 21:24

1 Answers1

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Intel has a paper, Improvements in the Intel® Core™2 Processor Family Architecture and Microarchitecture, in which they discuss a number of different division algorithms. The first paragraph:

The new Radix-16 floating-point divider with variable latency Radix-16 integer divide capability replaces the Merom Radix-4 floating point divide and Radix-2 square root and integer divide hardware. The preceding algorithm dated back to the Pentium® divide implementation.

So it looks like the Intel processors had the same integer divide (Radix-2) since the early Pentium days.

A Google search on radix 16 integer divide gives some very good information.

Cristian Ciupitu
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Jim Mischel
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