[llvm] [DependenceAnalysis] Extending SIV to handle separate loops (PR #128782)

[Michael Kruse via llvm-commits]

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@@ -523,10 +594,15 @@ namespace llvm {
     ///     e - 5
     ///     f - 6
     ///     g - 7 = MaxLevels
-    void establishNestingLevels(const Instruction *Src,
-                                const Instruction *Dst);
+    /// SeparateLevels counts the number of loop levels after the common levels
+    /// that are not identical but are considered similar. Two levels are
+    /// considered similar if they have the same trip count and the same
+    /// nesting depth.
+    /// For example, if loops `c` and `e` are similar, then they contribute to
+    /// the SeparateLevels count and SeparateLevels is set to 1.
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Meinersbur wrote:

Not messing up with the level count is a good thing.

https://github.com/llvm/llvm-project/pull/128782