1 files changed, 22 insertions, 20 deletions

diff --git a/llvm/lib/Transforms/Scalar/LoopStrengthReduce.cpp b/llvm/lib/Transforms/Scalar/LoopStrengthReduce.cpp
index 125f2cbc516..190fc5a2dc4 100644
--- a/llvm/lib/Transforms/Scalar/LoopStrengthReduce.cpp
+++ b/llvm/lib/Transforms/Scalar/LoopStrengthReduce.cpp
@@ -4315,28 +4315,10 @@ BasicBlock::iterator
 LSRInstance::HoistInsertPosition(BasicBlock::iterator IP,
                                  const SmallVectorImpl<Instruction *> &Inputs)
                                                                          const {
+  Instruction *Tentative = &*IP;
   for (;;) {
-    const Loop *IPLoop = LI.getLoopFor(IP->getParent());
-    unsigned IPLoopDepth = IPLoop ? IPLoop->getLoopDepth() : 0;
-
-    BasicBlock *IDom;
-    for (DomTreeNode *Rung = DT.getNode(IP->getParent()); ; ) {
-      if (!Rung) return IP;
-      Rung = Rung->getIDom();
-      if (!Rung) return IP;
-      IDom = Rung->getBlock();
-
-      // Don't climb into a loop though.
-      const Loop *IDomLoop = LI.getLoopFor(IDom);
-      unsigned IDomDepth = IDomLoop ? IDomLoop->getLoopDepth() : 0;
-      if (IDomDepth <= IPLoopDepth &&
-          (IDomDepth != IPLoopDepth || IDomLoop == IPLoop))
-        break;
-    }
-
     bool AllDominate = true;
     Instruction *BetterPos = nullptr;
-    Instruction *Tentative = IDom->getTerminator();
     // Don't bother attempting to insert before a catchswitch, their basic block
     // cannot have other non-PHI instructions.
     if (isa<CatchSwitchInst>(Tentative))
@@ -4349,7 +4331,7 @@ LSRInstance::HoistInsertPosition(BasicBlock::iterator IP,
       }
       // Attempt to find an insert position in the middle of the block,
       // instead of at the end, so that it can be used for other expansions.
-      if (IDom == Inst->getParent() &&
+      if (Tentative->getParent() == Inst->getParent() &&
           (!BetterPos || !DT.dominates(Inst, BetterPos)))
         BetterPos = &*std::next(BasicBlock::iterator(Inst));
     }
@@ -4359,6 +4341,26 @@ LSRInstance::HoistInsertPosition(BasicBlock::iterator IP,
       IP = BetterPos->getIterator();
     else
       IP = Tentative->getIterator();
+
+    const Loop *IPLoop = LI.getLoopFor(IP->getParent());
+    unsigned IPLoopDepth = IPLoop ? IPLoop->getLoopDepth() : 0;
+
+    BasicBlock *IDom;
+    for (DomTreeNode *Rung = DT.getNode(IP->getParent()); ; ) {
+      if (!Rung) return IP;
+      Rung = Rung->getIDom();
+      if (!Rung) return IP;
+      IDom = Rung->getBlock();
+
+      // Don't climb into a loop though.
+      const Loop *IDomLoop = LI.getLoopFor(IDom);
+      unsigned IDomDepth = IDomLoop ? IDomLoop->getLoopDepth() : 0;
+      if (IDomDepth <= IPLoopDepth &&
+          (IDomDepth != IPLoopDepth || IDomLoop == IPLoop))
+        break;
+    }
+
+    Tentative = IDom->getTerminator();
   }
 
   return IP;