[llvm] [LV][VPlan] Add initial support for CSA vectorization (PR #121222)

[Michael Maitland via llvm-commits]

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@@ -423,6 +424,71 @@ class InductionDescriptor {
   SmallVector<Instruction *, 2> RedundantCasts;
 };
 
+/// A Conditional Scalar Assignment is an assignment from an initial
+/// scalar that may or may not occur.
+class ConditionalScalarAssignmentDescriptor {
+  /// If the conditional assignment occurs inside a loop, then Phi chooses
+  /// the value of the assignment from the entry block or the loop body block.
+  PHINode *Phi = nullptr;
+
+  /// The initial value of the ConditionalScalarAssignment. If the condition
+  /// guarding the assignment is not met, then the assignment retains this
+  /// value.
+  Value *InitScalar = nullptr;
+
+  /// The Instruction that conditionally assigned to inside the loop.
+  Instruction *Assignment = nullptr;
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michaelmaitland wrote:

Updated.

https://github.com/llvm/llvm-project/pull/121222