[llvm] [X86] Use CUR_DIRECTION constant in more places. NFC (PR #185571)

[Simon Pilgrim via llvm-commits]

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@@ -22925,7 +22925,8 @@ SDValue X86TargetLowering::LowerFP_EXTEND(SDValue Op, SelectionDAG &DAG) const {
                        DAG.getVectorIdxConstant(0, DL));
       In = DAG.getBitcast(MVT::v8i16, In);
       Res = DAG.getNode(X86ISD::CVTPH2PS, DL, MVT::v4f32, In,
-                        DAG.getTargetConstant(4, DL, MVT::i32));
+                        DAG.getTargetConstant(
+                            X86::STATIC_ROUNDING::CUR_DIRECTION, DL, MVT::i32));
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RKSimon wrote:

X86ISD::CVTPH2PS shouldn't have a rounding mode at all - this is one of the verifyTargetNode failures in #185649

https://github.com/llvm/llvm-project/pull/185571