[llvm] [LoopInterchange] Improve profitability check for vectorization (PR #133672)

[Ryotaro Kasuga via llvm-commits]

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@@ -80,6 +80,21 @@ enum class RuleTy {
   ForVectorization,
 };
 
+/// Store the information about if corresponding direction vector was negated
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kasuga-fj wrote:

I did a quick check using llvm-test-suite, and found using `(direction vector, boolean value)` pairs as unique keys makes little difference in the number of entries (although in some cases the number of entries increased enormously if I stop making them unique). So changed to keep the negated and non-negated vectors separate.

https://github.com/llvm/llvm-project/pull/133672