These are the three remaining native builtins not yet ported.
There are elementwise versions of exp10 and tan which correspond to the
intrinsics, which may be preferable to the current versions which route
through other native builtins. Those could be changed in a follow-up if
desired.
This commit bulk updates all '.h', '.cl', '.inc', and '.cpp' files to
add any missing license headers.
The remaining files are generally CMake, SOURCES, scripts, markdown,
etc.
There are still some '.ll' files which may benefit from a license
header. I can't find an example of an LLVM IR file with a license header
in the rest of LLVM, but unlike most other (sub)projects, libclc has
examples of LLVM IR as source files, compiled and built into the
library.