trans-stmt.c (gfc_trans_forall_1): Optimize the cases where the mask expression is a compile-time constant...


	* trans-stmt.c (gfc_trans_forall_1): Optimize the cases where the
	mask expression is a compile-time constant (".true." or ".false.").

	* gfortran.dg/forall_8.f90: New test case.
	* gfortran.dg/forall_9.f90: Likewise.

From-SVN: r121714