C++ 128/256-bit fixed size integer types

Question

I was wondering if any fellow SO\'s could recommend a good light-weight fixed size integer type (128-bit or even 256-bit, possibly even template parametrized) library.

Answer 1

Some native 128-bit types are available on certain platforms, you tend to be limited by the architecture. For example __m128 is available for SSE2?

http://msdn.microsoft.com/en-us/library/ayeb3ayc.aspx

Also listed as __int128 in this ABI:

http://www.x86-64.org/documentation/abi-0.99.pdf

However the preferred naming of uint128_t and uint256_t can be found in SHOGUN, a "large scale machine learning toolbox with focus on especially Support Vector Machines (SVM)"

http://www.shogun-toolbox.org/doc/index.html