[llvm] [VPlan] Make canonical IV part of the region (PR #156262)

[Florian Hahn via llvm-commits]

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@@ -4377,23 +4337,33 @@ class LLVM_ABI_FOR_TEST VPRegionBlock : public VPBlockBase {
   /// VPRegionBlock.
   VPBlockBase *Exiting;
 
-  /// An indicator whether this region is to generate multiple replicated
-  /// instances of output IR corresponding to its VPBlockBases.
-  bool IsReplicator;
+  /// Holds the Canonical IV of the loop region along with additional
+  /// information. If CanIVInfo is nullptr, the region is a replicating region.
+  /// Loop regions retain their canonical IVs until they are dissolved, even if
+  /// the canonical IV has no users.
+  std::unique_ptr<VPCanonicalIVInfo> CanIVInfo;
 
-  /// Use VPlan::createVPRegionBlock to create VPRegionBlocks.
+  /// Use VPlan::createLoopRegion() and VPlan::createReplicateRegion() to create
+  /// VPRegionBlocks.
   VPRegionBlock(VPBlockBase *Entry, VPBlockBase *Exiting,
-                const std::string &Name = "", bool IsReplicator = false)
-      : VPBlockBase(VPRegionBlockSC, Name), Entry(Entry), Exiting(Exiting),
-        IsReplicator(IsReplicator) {
-    assert(Entry->getPredecessors().empty() && "Entry block has predecessors.");
-    assert(Exiting->getSuccessors().empty() && "Exit block has successors.");
-    Entry->setParent(this);
-    Exiting->setParent(this);
-  }
-  VPRegionBlock(const std::string &Name = "", bool IsReplicator = false)
-      : VPBlockBase(VPRegionBlockSC, Name), Entry(nullptr), Exiting(nullptr),
-        IsReplicator(IsReplicator) {}
+                const std::string &Name = "")
+      : VPBlockBase(VPRegionBlockSC, Name), Entry(Entry), Exiting(Exiting) {
+    if (Entry) {
+      assert(Entry->getPredecessors().empty() &&
+             "Entry block has predecessors.");
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fhahn wrote:

done thanks

https://github.com/llvm/llvm-project/pull/156262