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  1. March 2nd, 2011 03:06 PM #1
    paprica
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    A question about integers

    Will
    Code:
    int i = 10000000;
i++;
    take more time to process than
    Code:
    int i = 0;
i++;
    ?
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  2. March 2nd, 2011 03:15 PM #2
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    D_Drmmr
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    Re: A question about integers

    No.
    Cheers, D Drmmr

    Please put [code][/code] tags around your code to preserve indentation and make it more readable.

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  3. March 3rd, 2011 06:42 AM #3
    ninja9578
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    Re: A question about integers

    They will both compile down to
    Code:
    push 1000000
inc [&#37;%sp]
    and
    Code:
    push 0
inc [%%sp]
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  4. March 3rd, 2011 07:05 AM #4
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    monarch_dodra
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    Re: A question about integers

    Quote Originally Posted by ninja9578 View Post
    They will both compile down to
    Code:
    push 1000000
inc [%%sp]
    and
    Code:
    push 0
inc [%%sp]
    or

    Code:
    push 1000001
    and
    Code:
    push 1
    Is your question related to IO?
    Read this C++ FAQ LITE article at parashift by Marshall Cline. In particular points 1-6.
    It will explain how to correctly deal with IO, how to validate input, and why you shouldn't count on "while(!in.eof())". And it always makes for excellent reading.
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  5. March 3rd, 2011 08:00 AM #5
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    Eri523
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    Re: A question about integers

    IMO both your assembly variants are unlikely. The OP's code shows no reason to push the int at all because it's not going to be passed as a function parameter.

    I'd say discussing assembly details here is moot anyway and not really helpful to the OP...

    EDIT: Ok, I need to take back my statement about no need to push the int as the variable is just being constructed. Looks like I wrote the post too quickly. But the second paragraph still holds true IMO...
    Last edited by Eri523; March 3rd, 2011 at 08:07 AM.
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  6. March 3rd, 2011 08:11 AM #6
    ninja9578
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    Re: A question about integers

    Quote Originally Posted by monarch_dodra View Post
    or

    Code:
    push 1000001
    and
    Code:
    push 1
    Probably not on -O0
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