Backport PRs 61729, 73650, 77850, 80382, 80618, 80692, 80902, 80966

Backport PRs 61729, 73650, 77850, 80382, 80618, 80692, 80902, 80966

	Backports from trunk:

	2016-08-15  Segher Boessenkool  <segher@kernel.crashing.org>
	PR rtl-optimization/73650
	* lra-constraints.c (simple_move_p): If the insn is multiple_sets
	it is not a simple move.

	2017-01-20  Segher Boessenkool  <segher@kernel.crashing.org>
	PR target/61729
	PR target/77850
	* config/rs6000/rs6000.c (rs6000_gimplify_va_arg): Adjust address to
	read from, for big endian.

	2017-04-12  Segher Boessenkool  <segher@kernel.crashing.org>
	PR target/80382
	* config/rs6000/sync.md (atomic_load<mode>, atomic_store<mode): Test
	for quad_address_p for TImode, instead of just not indexed_address.

	2017-05-17  Segher Boessenkool  <segher@kernel.crashing.org>
	PR middle-end/80692
	* real.c (do_compare): Give decimal_do_compare preference over
	comparing just the signs.

	2017-05-31  Segher Boessenkool  <segher@kernel.crashing.org>
	PR target/80618
	* config/rs6000/vector.md (*vector_uneq<mode>): Write the nor in the
	splitter result in the canonical way.

	2017-06-09  Segher Boessenkool  <segher@kernel.crashing.org>
	PR target/80966
	* config/rs6000/rs6000.c (rs6000_emit_allocate_stack): Assert that
	gen_add3_insn did not fail.
	* config/rs6000/rs6000.md (add<mode>3): If asked to add a constant to
	r0, construct that number in a temporary reg and add that reg to r0.
	If asked to put the result in r0 as well, fail.

	2017-06-23  Segher Boessenkool  <segher@kernel.crashing.org>
	PR middle-end/80902
	* builtins.c (expand_builtin_atomic_fetch_op): If emitting code after
	a call, force the call to not be a tail call.

gcc/testsuite/
	Backports from trunk:

	2017-05-17  Segher Boessenkool  <segher@kernel.crashing.org>
	PR middle-end/80692
	* gcc.c-torture/execute/pr80692.c: New testcase.

	2017-06-09  Segher Boessenkool  <segher@kernel.crashing.org>
	PR target/80966
	* gcc.target/powerpc/stack-limit.c: New testcase.

From-SVN: r249707