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

[via llvm-commits]

================
@@ -3217,60 +3210,49 @@ class VPExpandSCEVRecipe : public VPSingleDefRecipe {
   const SCEV *getSCEV() const { return Expr; }
 };
 
-/// Canonical scalar induction phi of the vector loop. Starting at the specified
+/// Canonical scalar induction of the vector loop. Starting at the specified
 /// start value (either 0 or the resume value when vectorizing the epilogue
-/// loop). VPWidenCanonicalIVRecipe represents the vector version of the
-/// canonical induction variable.
-class VPCanonicalIVPHIRecipe : public VPHeaderPHIRecipe {
+/// loop).
+class VPCanonicalIV : public VPValue, public VPUser {
+  bool HasNUW = true;
+  DebugLoc DL;
+
 public:
-  VPCanonicalIVPHIRecipe(VPValue *StartV, DebugLoc DL)
-      : VPHeaderPHIRecipe(VPDef::VPCanonicalIVPHISC, nullptr, StartV, DL) {}
+  VPCanonicalIV(VPValue *StartV, bool HasNUW = true,
+                DebugLoc DL = DebugLoc::getUnknown())
+      : VPValue(VPValue::VPCanonicalIVSC), VPUser(StartV), HasNUW(HasNUW),
+        DL(DL) {}
 
-  ~VPCanonicalIVPHIRecipe() override = default;
+  ~VPCanonicalIV() override = default;
 
-  VPCanonicalIVPHIRecipe *clone() override {
-    auto *R = new VPCanonicalIVPHIRecipe(getOperand(0), getDebugLoc());
-    R->addOperand(getBackedgeValue());
-    return R;
+  VPCanonicalIV *clone() {
+    auto *CanIV = new VPCanonicalIV(getOperand(0), HasNUW, DL);
+    return CanIV;
----------------
ayalz wrote:

```suggestion
    return new VPCanonicalIV(getOperand(0), HasNUW, DL);
```

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