How to Multiply 64 bit Numbers in LabVIEW

What is the product of 0x9D0BF6FDAC70AB52 and 0x6408F6540A1384CB?  Well, according to LabVIEW for Windows, the answer is 0x2D90DE07C0C42206.  According to C++ on OSX (without any optimizations, usage of Intel Intrinsic functions), the answer is also 0x2D90DE07C0C42206.

The real answer is…  0x3D5E2BF7DCBCA6622D90DE07C0C42206.

How do you get this number? You have to use compiler intrinsics, or calculate this value yourself.  LabVIEW does not make it easy to call an Intel Compiler intrinsic, so I took it upon myself to implement this myself.  Here is a screenshot of the implementation in LabVIEW for Windows:

To download and use this code in your project, see:

Note: FPGA version is coming soon, but I am busy working on something else right now


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