[llvm] [WIP][SelectionDAG] Add support for the 3-way comparison intrinsics [US]CMP (PR #91871)

[Nikita Popov via llvm-commits]

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@@ -677,6 +677,11 @@ enum NodeType {
   UMIN,
   UMAX,
 
+  /// [US]CMP - 3-way comparison of signed or unsigned integers. Returns -1, 0,
+  /// or 1 depending on whether Op0 <, ==, or > Op1
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nikic wrote:

I'd mention that the result and operand types can differ here.

https://github.com/llvm/llvm-project/pull/91871