[llvm] [VPlan] Make CanIV part of region. (PR #144803)

[via llvm-commits]

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@@ -3776,12 +3760,29 @@ class LLVM_ABI_FOR_TEST VPRegionBlock : public VPBlockBase {
     Entry->setParent(this);
     Exiting->setParent(this);
   }
-  VPRegionBlock(const std::string &Name = "", bool IsReplicator = false)
+  VPRegionBlock(VPBlockBase *Entry, VPBlockBase *Exiting, VPCanonicalIV *CanIV,
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ayalz wrote:

```suggestion

  VPRegionBlock(VPBlockBase *Entry, VPBlockBase *Exiting, VPCanonicalIV *CanIV,
```

https://github.com/llvm/llvm-project/pull/144803