[llvm] [RISCV] Support postRA vsetvl insertion pass (PR #70549)

[Piyou Chen via llvm-commits]

================
@@ -19,9 +19,9 @@ define <2 x half> @nearbyint_v2f16(<2 x half> %v) strictfp {
 ; CHECK-NEXT:    frflags a0
 ; CHECK-NEXT:    vfcvt.x.f.v v9, v8, v0.t
 ; CHECK-NEXT:    vfcvt.f.x.v v9, v9, v0.t
-; CHECK-NEXT:    fsflags a0
----------------
BeMg wrote:

> @BeMg Do we still get this diff if we rebase on top of main now that #91319 is landed? (Sorry for the conflicts!)

After rebase, there aren't test diff on fixed-vectors-fnearbyint-constrained-sdnode.ll.

https://github.com/llvm/llvm-project/pull/70549