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A comment on Faster remainders when the divisor is a constant: beating compilers & libdivide. Parent comment

Re:Faster remainders when the divisor is a constant: beating... by saagarjha on Saturday February 09, 2019 @04:13AM (#19121461)
This was exactly what I was about to mention; I can reproduce your results in Clang but it seems GCC doesn't want to optimize this? Here's what Godbolt gives me: https://godbolt.org/z/aFTdur
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Re:Faster remainders when the divisor is a constant: beating... by acqq on Saturday February 09, 2019 @10:24AM (#19122696)
Just write a function “mydiv10” which returns if x < 99 { x /10 and 0 otherwise and try again.
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Re:Faster remainders when the divisor is a constant: beating... by acqq on Sunday February 10, 2019 @04:39PM (#19130218)
Like this:

https://godbolt.org/z/bS2yzB

But also note that when the input is unsigned short we get:

https://godbolt.org/z/sbDbMU

        movzx   eax, di
        imul    eax, eax, 52429
        shr     eax, 19
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