[llvm] [VPlan] Hook IR blocks into VPlan during skeleton creation (NFC) (PR #114292)

[via llvm-commits]

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@@ -1181,6 +1181,20 @@ std::string VPlan::getName() const {
   return Out;
 }
 
+VPRegionBlock *VPlan::getVectorLoopRegion() {
+  for (VPBlockBase *B : vp_depth_first_shallow(getEntry()))
+    if (auto *R = dyn_cast<VPRegionBlock>(B))
+      return R;
+  return nullptr;
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ayalz wrote:

Better cache the result? Can be done as follow-up.

https://github.com/llvm/llvm-project/pull/114292