[nvptx] Fix calls to vector and worker routines

[nvptx] Fix calls to vector and worker routines

2018-04-20  Nathan Sidwell  <nathan@codesourcery.com>
	    Tom de Vries  <tom@codesourcery.com>

	PR target/85445
	* config/nvptx/nvptx.c (nvptx_emit_forking, nvptx_emit_joining):
	Emit insns for calls too.
	(nvptx_find_par): Always look for worker-level predecessor insn.
	(nvptx_propagate): Add is_call parm, return bool.  Copy frame for
	calls.
	(nvptx_vpropagate, nvptx_wpropagate): Adjust.
	(nvptx_process_pars): Propagate frames for calls.

	* testsuite/libgomp.oacc-c++/ref-1.C: New.

Co-Authored-By: Tom de Vries <tom@codesourcery.com>
From-SVN: r259523