1 files changed, 17 insertions, 9 deletions
diff --git a/llvm/lib/Transforms/Utils/LCSSA.cpp b/llvm/lib/Transforms/Utils/LCSSA.cpp
index a6895cc..5f1c98c 100644
--- a/llvm/lib/Transforms/Utils/LCSSA.cpp
+++ b/llvm/lib/Transforms/Utils/LCSSA.cpp
@@ -76,6 +76,7 @@ static bool isExitBlock(BasicBlock *BB,
 /// rewrite the uses.
 bool llvm::formLCSSAForInstructions(SmallVectorImpl<Instruction *> &Worklist,
                                     const DominatorTree &DT, const LoopInfo &LI,
+                                    ScalarEvolution *Se,
                                     SmallVectorImpl<PHINode *> *PHIsToRemove,
                                     SmallVectorImpl<PHINode *> *InsertedPHIs) {
   SmallVector<Use *, 16> UsesToRewrite;
@@ -333,7 +334,8 @@ static void computeBlocksDominatingExits(
   }
 }
 
-bool llvm::formLCSSA(Loop &L, const DominatorTree &DT, const LoopInfo *LI) {
+bool llvm::formLCSSA(Loop &L, const DominatorTree &DT, const LoopInfo *LI,
+                     ScalarEvolution *SE) {
   bool Changed = false;
 
 #ifdef EXPENSIVE_CHECKS
@@ -386,7 +388,7 @@ bool llvm::formLCSSA(Loop &L, const DominatorTree &DT, const LoopInfo *LI) {
     }
   }
 
-  Changed = formLCSSAForInstructions(Worklist, DT, *LI);
+  Changed = formLCSSAForInstructions(Worklist, DT, *LI, SE);
 
   assert(L.isLCSSAForm(DT));
 
@@ -395,22 +397,23 @@ bool llvm::formLCSSA(Loop &L, const DominatorTree &DT, const LoopInfo *LI) {
 
 /// Process a loop nest depth first.
 bool llvm::formLCSSARecursively(Loop &L, const DominatorTree &DT,
-                                const LoopInfo *LI) {
+                                const LoopInfo *LI, ScalarEvolution *SE) {
   bool Changed = false;
 
   // Recurse depth-first through inner loops.
   for (Loop *SubLoop : L.getSubLoops())
-    Changed |= formLCSSARecursively(*SubLoop, DT, LI);
+    Changed |= formLCSSARecursively(*SubLoop, DT, LI, SE);
 
-  Changed |= formLCSSA(L, DT, LI);
+  Changed |= formLCSSA(L, DT, LI, SE);
   return Changed;
 }
 
 /// Process all loops in the function, inner-most out.
-static bool formLCSSAOnAllLoops(const LoopInfo *LI, const DominatorTree &DT) {
+static bool formLCSSAOnAllLoops(const LoopInfo *LI, const DominatorTree &DT,
+                                ScalarEvolution *SE) {
   bool Changed = false;
   for (const auto &L : *LI)
-    Changed |= formLCSSARecursively(*L, DT, LI);
+    Changed |= formLCSSARecursively(*L, DT, LI, SE);
   return Changed;
 }
 
@@ -424,6 +427,7 @@ struct LCSSAWrapperPass : public FunctionPass {
   // Cached analysis information for the current function.
   DominatorTree *DT;
   LoopInfo *LI;
+  ScalarEvolution *SE;
 
   bool runOnFunction(Function &F) override;
   void verifyAnalysis() const override {
@@ -480,13 +484,17 @@ char &llvm::LCSSAID = LCSSAWrapperPass::ID;
 bool LCSSAWrapperPass::runOnFunction(Function &F) {
   LI = &getAnalysis<LoopInfoWrapperPass>().getLoopInfo();
   DT = &getAnalysis<DominatorTreeWrapperPass>().getDomTree();
-  return formLCSSAOnAllLoops(LI, *DT);
+  auto *SEWP = getAnalysisIfAvailable<ScalarEvolutionWrapperPass>();
+  SE = SEWP ? &SEWP->getSE() : nullptr;
+
+  return formLCSSAOnAllLoops(LI, *DT, SE);
 }
 
 PreservedAnalyses LCSSAPass::run(Function &F, FunctionAnalysisManager &AM) {
   auto &LI = AM.getResult<LoopAnalysis>(F);
   auto &DT = AM.getResult<DominatorTreeAnalysis>(F);
-  if (!formLCSSAOnAllLoops(&LI, DT))
+  auto *SE = AM.getCachedResult<ScalarEvolutionAnalysis>(F);
+  if (!formLCSSAOnAllLoops(&LI, DT, SE))
     return PreservedAnalyses::all();
 
   PreservedAnalyses PA;