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

[Julius Alexandre via llvm-commits]

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@@ -2493,6 +2497,19 @@ SDValue DAGTypeLegalizer::PromoteIntOp_SELECT(SDNode *N, unsigned OpNo) {
                                         N->getOperand(2)), 0);
 }
 
+SDValue DAGTypeLegalizer::PromoteIntOp_CT_SELECT(SDNode *N, unsigned OpNo) {
+  assert(OpNo == 0 && "Only know how to promote the condition!");
+  SDValue Cond = N->getOperand(0);
+  EVT OpTy = N->getOperand(1).getValueType();
+
+  // Promote all the way up to the canonical SetCC type.
+  EVT OpVT = N->getOpcode() == ISD::CT_SELECT ? OpTy.getScalarType() : OpTy;
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wizardengineer wrote:

Removed the opcode check in 64613ed31ef6.

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