[clang] [CIR] Upstream ThreeWayCmpOp (PR #169963)

[Hendrik Hübner via cfe-commits]

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@@ -447,6 +447,68 @@ def CIR_ConstPtrAttr : CIR_Attr<"ConstPtr", "ptr", [TypedAttrInterface]> {
   }];
 }
 
+//===----------------------------------------------------------------------===//
+// CmpThreeWayInfoAttr
+//===----------------------------------------------------------------------===//
+
+def CIR_CmpOrdering : CIR_I32EnumAttr<
+  "CmpOrdering", "three-way comparison ordering kind", [
+    I32EnumAttrCase<"Strong", 0, "strong">,
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HendrikHuebner wrote:

The code gen for strong and weak comparison is the same, let's rename the case here to `Total` instead (as opposed to `Partial`).

https://github.com/llvm/llvm-project/pull/169963