gcc/libhsail-rt

This library implements the agent-side runtime functionality required
to run HSA finalized programs produced by the BRIG frontend.

The library contains both the code required to run kernels on the agent
and also functions implementing more complex HSAIL instructions.

rt/workitems.c contains the runtime entry function that manages multiple
work-item execution using fibers or simple for-loops (in case of work groups
without barriers).  Otherwise, the rest of the source files mostly contain
functions that typically map directly to HSAIL instructions.