[llvm] [ConstantTime][LLVM] Add llvm.ct.select intrinsic with generic SelectionDAG lowering (PR #166702)

[Julius Alexandre via llvm-commits]

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@@ -5709,7 +5864,8 @@ void SelectionDAGLegalize::PromoteNode(SDNode *Node) {
     Tmp2 = DAG.getNode(ExtOp, dl, NVT, Node->getOperand(1));
     Tmp3 = DAG.getNode(ExtOp, dl, NVT, Node->getOperand(2));
     // Perform the larger operation, then round down.
-    Tmp1 = DAG.getSelect(dl, NVT, Tmp1, Tmp2, Tmp3);
+    Tmp1 = DAG.getNode(Node->getOpcode(), dl, NVT, Tmp1, Tmp2, Tmp3);
+    Tmp1->setFlags(Node->getFlags());
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wizardengineer wrote:

Done in 64613ed31ef6. Flags now go straight into getNode instead of being set after.

https://github.com/llvm/llvm-project/pull/166702