[llvm] [LV][VPlan] Add initial support for CSA vectorization (PR #106560)

[Ramkumar Ramachandra via llvm-commits]

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@@ -79,6 +79,10 @@ static cl::opt<LoopVectorizeHints::ScalableForceKind>
                 "Scalable vectorization is available and favored when the "
                 "cost is inconclusive.")));
 
+static cl::opt<bool>
+    EnableCSA("enable-csa-vectorization", cl::init(false), cl::Hidden,
+              cl::desc("Control whether CSA loop vectorization is enabled"));
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artagnon wrote:

Why guard it under a flag? Seems useful in the general case.

https://github.com/llvm/llvm-project/pull/106560