[llvm-dev] on division of __int128 bit integer (original) (raw)
Vivek Pandey via llvm-dev llvm-dev at lists.llvm.org
Thu May 21 02:30:15 PDT 2020
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Hi Team,
I observer that division of __int128 bit is very heavy operation. It internally call a routine '__udivti3', which internally call ' __udivmodti4'.
Due to it the overall performance is much much slower (almost 15 time slower than if I do it via a combination of 64-bit or microsoft '_udiv128').
Also what to know if I can directly call below routine directly from my code : unsigned long long __udivmodti4 *(unsigned long long a, unsigned long long b, unsigned long long c)
This is against statement "Conceptually,in operation, like ‘/’ or ‘%’, no function is called, so no header is provided for __udivmodti4 etc. – and we should not call them explicitly in our code." but wanted to know more on it.
Thank you! Regards, Vivek JP Pandey, Software Professional, +91-7775054441 -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.llvm.org/pipermail/llvm-dev/attachments/20200521/2effa903/attachment.html>
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