Fix host/device calls for __half.

The previous code had `__host__ __device__` functions calling `__device__`
functions (e.g. `__low2half`) which caused build failures in tensorflow.
Also tried to simplify the `#ifdef` guards to make them more clear.
1 file changed
tree: b568be6551dca471996fa5864ee6615b620a7052
  1. bench/
  2. blas/
  3. ci/
  4. cmake/
  5. debug/
  6. demos/
  7. doc/
  8. Eigen/
  9. failtest/
  10. lapack/
  11. scripts/
  12. test/
  13. unsupported/
  14. .gitignore
  15. .gitlab-ci.yml
  16. .hgeol
  17. CMakeLists.txt
  18. COPYING.APACHE
  19. COPYING.BSD
  20. COPYING.GPL
  21. COPYING.LGPL
  22. COPYING.MINPACK
  23. COPYING.MPL2
  24. COPYING.README
  25. CTestConfig.cmake
  26. CTestCustom.cmake.in
  27. eigen3.pc.in
  28. INSTALL
  29. README.md
  30. signature_of_eigen3_matrix_library
README.md

Eigen is a C++ template library for linear algebra: matrices, vectors, numerical solvers, and related algorithms.

For more information go to http://eigen.tuxfamily.org/.

For pull request, bug reports, and feature requests, go to https://gitlab.com/libeigen/eigen.