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

[Michael Maitland via llvm-commits]

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@@ -1245,6 +1314,14 @@ class VPInstruction : public VPRecipeWithIRFlags,
     // operand). Only generates scalar values (either for the first lane only or
     // for all lanes, depending on its uses).
     PtrAdd,
+    CSAInitMask,
+    CSAInitData,
+    CSAMaskPhi,
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michaelmaitland wrote:

> and at least some of them can be more generic (e.g. AnyActive would be useful for more than just CSA).

I've removed `CSA` from `CSAAnyActive`, since it might be useful for non-csa patterns in the future.

> Can the InitMask/Data instructions be generated where used by getVPValueOrLiveIn using a constant instead?

Done.

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