[AVX-512] Don't lower CVTPD2PS intrinsics to ISD::FP_ROUND with an X86 rounding mode encoding in the second operand. This immediate should only be 0 or 1 and indicates if the truncation loses precision.

Also enhance an assert in SelectionDAG::getNode to flag this sort of problem in the future.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@281868 91177308-0d34-0410-b5e6-96231b3b80d8
3 files changed