Jul 20, 2023

C/C++ header-only library for division via FP inverse multiplication

Header-only library for division via fixed-point multiplication by inverse.

On modern CPUs and GPUs integer division is several times slower than multiplication. FXdiv implements an algorithm to replace an integer division with a multiplication and two shifts. This algorithm improves performance when an application performs repeated divisions by the same divisor.


  • Integer division for uint32_t, uint64_t, and size_t
  • Header-only library, no installation or build required
  • Compatible with C99, C++, OpenCL, and CUDA
  • Uses platform-specific compiler intrinsics for optimal performance
  • Covered with unit tests and microbenchmarks

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