This series of patches fix PR61441. This patch makes resulting NaN values

This series of patches fix PR61441. This patch makes resulting NaN values
to be quiet NaN for real value operations, irrespective of the flag_signaling_nans
flag. The caller has the responsibility to avoid the operation if flag_signaling_nans
is on.

gcc/
	* real.c (do_add): Make resulting NaN value to be qNaN.
	(do_multiply, do_divide, do_fix_trunc): Same.
	(real_arithmetic, real_ldexp, real_convert): Same.
	(real_isinteger): Updated comment stating it returns false for sNaN.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@231872 138bc75d-0d04-0410-961f-82ee72b054a4