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

[Julius Alexandre via llvm-commits]

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@@ -1417,6 +1417,13 @@ class SelectionDAG {
     return getNode(Opcode, DL, VT, Cond, LHS, RHS, Flags);
   }
 
+  SDValue getCTSelect(const SDLoc &DL, EVT VT, SDValue Cond, SDValue LHS,
+                      SDValue RHS, SDNodeFlags Flags = SDNodeFlags()) {
+    assert(LHS.getValueType() == VT && RHS.getValueType() == VT &&
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wizardengineer wrote:

Added the scalar-condition assert in 64613ed31ef6.

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