[DUG] Int64 or floating point faster?

[Jolyon Smith]

@Pieter - I don't understand what you mean when you say that "float was
int32.int32".  For starters, "float" is an imprecise term.  If you mean
"single" then the entire value was always 32 bit in it's entirety.  If you
mean double then it was always 64 bit.  What is this "in32.int32" type of
which you speak ?  O.o


On 17 August 2014 11:52, Jolyon Smith <jsmith at deltics.co.nz> wrote:

> I think there are too many variables involved to give an answer to this
> question without some of those variables being reduced to known values.
>
> e.g.  what hardware ?  what version of Delphi ?  x64 target or x86 ?  what
> precision of floating point ?
>
> Having said that, in a quick test knocked up in my Smoketest framework I
> found that Double comfortably outperforms Int64 when compiling for Win32
> but that both Double and Int64 demonstrated improved performance when
> compiling for Win64 and that whilst Double still showed some advantage it
> was not as significant (and in some test runs the difference was
> negligible).
>
> If you are targeting FireMonkey you will have to bear in mind that the
> back-end compiler is different to the x86/x64 backend, so results obtained
> using the WinXX compilers will not necessarily be indicative of performance
> on the ARM or LLVM platforms.
>
>
> Conditions:
>
>  - Delphi XE4
>  - Running in a 64-bit Win 7 VM
>  - No testing was done for correctness of the results.
>
>
>
>
>
> On 16 August 2014 15:30, Ross Levis <ross at stationplaylist.com> wrote:
>
>> Would I be correct that int64 multiplications would be faster than
>> floating point in Delphi?  My app needs to do several million.
>>
>>
>>
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