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

[Michael Kruse via llvm-commits]

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@@ -264,27 +313,37 @@ namespace llvm {
     bool normalize(ScalarEvolution *SE) override;
 
     /// isPeelFirst - Returns true if peeling the first iteration from
-    /// this loop will break this dependence.
-    bool isPeelFirst(unsigned Level) const override;
+    /// this loop will break this dependence. If Separate is set to true,
+    /// information about a separate level is provided.
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Meinersbur wrote:

There is nothing in the header file that even explains what a "separate level" actually is. Rather than having this sentence not saying anything here, consider central documentation whati t means, e.g. as class comment.

Could contain:
 * Number of loops inside common loops that are "similar" (+definition of similar)
 * Have different `llvm::Loop` objects but can be interpreted as a single fused loop with `Separate=true`

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