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A comment on A Special Kind of Hell: intmax_t in C and C++. Parent comment

Re:A Special Kind of Hell: intmax_t in C and C++ by Gibbon1 on Saturday December 05, 2020 @09:06PM (#25320359)
Exactly, if the coder thinks those optimizations will buy him anything then let them enable them for that one case. And stop pretending that micro benchmarks matter for the rest of the 99.9% of code out there.

Last time I looked at the speedup you got from loop optimization it at most a few percent for a very simple loop. For a loop that has some meat it'd be noise.

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Re:A Special Kind of Hell: intmax_t in C and C++ by fooker on Sunday December 06, 2020 @03:28AM (#25322033)
> Last time I looked at the speedup you got from loop optimization it at most a few percent for a very simple loop.

Wow, no. Most loop optimizations make loops significantly faster, even an order of magnitude is not uncommon. Write a few loops and compare the code generated by any compiler with O0 vs O3.

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