[VPlan] Move two VPBlockUtils members (NFC) (#162507)

Author: artagnon

llvm/lib/Transforms/Vectorize/VPlan.cpp

@@ -217,32 +217,6 @@ VPBlockBase *VPBlockBase::getEnclosingBlockWithPredecessors() {
   return Parent->getEnclosingBlockWithPredecessors();
 }
 
-bool VPBlockUtils::isHeader(const VPBlockBase *VPB,
-                            const VPDominatorTree &VPDT) {
-  auto *VPBB = dyn_cast<VPBasicBlock>(VPB);
-  if (!VPBB)
-    return false;
-
-  // If VPBB is in a region R, VPBB is a loop header if R is a loop region with
-  // VPBB as its entry, i.e., free of predecessors.
-  if (auto *R = VPBB->getParent())
-    return !R->isReplicator() && !VPBB->hasPredecessors();
-
-  // A header dominates its second predecessor (the latch), with the other
-  // predecessor being the preheader
-  return VPB->getPredecessors().size() == 2 &&
-         VPDT.dominates(VPB, VPB->getPredecessors()[1]);
-}
-
-bool VPBlockUtils::isLatch(const VPBlockBase *VPB,
-                           const VPDominatorTree &VPDT) {
-  // A latch has a header as its second successor, with its other successor
-  // leaving the loop. A preheader OTOH has a header as its first (and only)
-  // successor.
-  return VPB->getNumSuccessors() == 2 &&
-         VPBlockUtils::isHeader(VPB->getSuccessors()[1], VPDT);
-}
-
 VPBasicBlock::iterator VPBasicBlock::getFirstNonPhi() {
   iterator It = begin();
   while (It != end() && It->isPhi())

llvm/lib/Transforms/Vectorize/VPlanUtils.cpp

@@ -8,6 +8,7 @@
 
 #include "VPlanUtils.h"
 #include "VPlanCFG.h"
+#include "VPlanDominatorTree.h"
 #include "VPlanPatternMatch.h"
 #include "llvm/ADT/TypeSwitch.h"
 #include "llvm/Analysis/ScalarEvolutionExpressions.h"
@@ -253,3 +254,29 @@ vputils::getRecipesForUncountableExit(VPlan &Plan,
 
   return UncountableCondition;
 }
+
+bool VPBlockUtils::isHeader(const VPBlockBase *VPB,
+                            const VPDominatorTree &VPDT) {
+  auto *VPBB = dyn_cast<VPBasicBlock>(VPB);
+  if (!VPBB)
+    return false;
+
+  // If VPBB is in a region R, VPBB is a loop header if R is a loop region with
+  // VPBB as its entry, i.e., free of predecessors.
+  if (auto *R = VPBB->getParent())
+    return !R->isReplicator() && !VPBB->hasPredecessors();
+
+  // A header dominates its second predecessor (the latch), with the other
+  // predecessor being the preheader
+  return VPB->getPredecessors().size() == 2 &&
+         VPDT.dominates(VPB, VPB->getPredecessors()[1]);
+}
+
+bool VPBlockUtils::isLatch(const VPBlockBase *VPB,
+                           const VPDominatorTree &VPDT) {
+  // A latch has a header as its second successor, with its other successor
+  // leaving the loop. A preheader OTOH has a header as its first (and only)
+  // successor.
+  return VPB->getNumSuccessors() == 2 &&
+         VPBlockUtils::isHeader(VPB->getSuccessors()[1], VPDT);
+}