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Where Intel Processors Fail At Math (Again)

rastos1 writes: In a recent blog, software developer Bruce Dawson pointed out some issues with the way the FSIN instruction is described in the "Intel® 64 and IA-32 Architectures Software Developer's Manual," noting that the result of FSIN can be very inaccurate in some cases, if compared to the exact mathematical value of the sine function.

Dawson says, "I was shocked when I discovered this. Both the fsin instruction and Intel's documentation are hugely inaccurate, and the inaccurate documentation has led to poor decisions being made. ... Intel has known for years that these instructions are not as accurate as promised. They are now making updates to their documentation. Updating the instruction is not a realistic option."

Intel processors have had a problem with math in the past, too.

6 of 239 comments (clear)

  1. Intel Common Core i7 by Spy+Handler · · Score: 5, Funny

    with new maths

    1. Re:Intel Common Core i7 by Falos · · Score: 4, Funny

      1+1=3 for particularly large values of 1

    2. Re: Intel Common Core i7 by Anonymous Coward · · Score: 3, Funny

      "'8 + 5 = 10' is True or false"

      Is True.

  2. Bad intel by Tablizer · · Score: 3, Funny

    We already know it's a sin to eat pi.

  3. Re:Say what? by serviscope_minor · · Score: 4, Funny

    We are pentium of borg. Division is futile. You will be approximated.

    From what I remember it was the first revision of the Pentium 1 aka the Pentium 0.999998163849

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  4. Re:My workaround by lgw · · Score: 4, Funny

    The positive or the negative root?

    I just use the average of the two, for predictable output.

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    Socialism: a lie told by totalitarians and believed by fools.