Preserve CFG in MergedLoadStoreMotion. This fixes PR24426.

[oota-llvm.git] / lib / Transforms / Scalar / NaryReassociate.cpp

diff --git a/lib/Transforms/Scalar/NaryReassociate.cpp b/lib/Transforms/Scalar/NaryReassociate.cpp
index 972bd335c8527c525dd80ea5832046e63c96c05c..930552d2f9043855e2625f8a482d31953d553644 100644 (file)
--- a/lib/Transforms/Scalar/NaryReassociate.cpp
+++ b/lib/Transforms/Scalar/NaryReassociate.cpp
@@ -246,21 +246,21 @@ bool NaryReassociate::doOneIteration(Function &F) {
        Node != GraphTraits<DominatorTree *>::nodes_end(DT); ++Node) {
     BasicBlock *BB = Node->getBlock();
     for (auto I = BB->begin(); I != BB->end(); ++I) {
-      if (SE->isSCEVable(I->getType()) && isPotentiallyNaryReassociable(I)) {
-        const SCEV *OldSCEV = SE->getSCEV(I);
-        if (Instruction *NewI = tryReassociate(I)) {
+      if (SE->isSCEVable(I->getType()) && isPotentiallyNaryReassociable(&*I)) {
+        const SCEV *OldSCEV = SE->getSCEV(&*I);
+        if (Instruction *NewI = tryReassociate(&*I)) {
           Changed = true;
-          SE->forgetValue(I);
+          SE->forgetValue(&*I);
           I->replaceAllUsesWith(NewI);
           // If SeenExprs constains I's WeakVH, that entry will be replaced with
           // nullptr.
-          RecursivelyDeleteTriviallyDeadInstructions(I, TLI);
-          I = NewI;
+          RecursivelyDeleteTriviallyDeadInstructions(&*I, TLI);
+          I = NewI->getIterator();
         }
         // Add the rewritten instruction to SeenExprs; the original instruction
         // is deleted.
-        const SCEV *NewSCEV = SE->getSCEV(I);
-        SeenExprs[NewSCEV].push_back(WeakVH(I));
+        const SCEV *NewSCEV = SE->getSCEV(&*I);
+        SeenExprs[NewSCEV].push_back(WeakVH(&*I));
         // Ideally, NewSCEV should equal OldSCEV because tryReassociate(I)
         // is equivalent to I. However, ScalarEvolution::getSCEV may
         // weaken nsw causing NewSCEV not to equal OldSCEV. For example, suppose
@@ -280,7 +280,7 @@ bool NaryReassociate::doOneIteration(Function &F) {
         //
         // This improvement is exercised in @reassociate_gep_nsw in nary-gep.ll.
         if (NewSCEV != OldSCEV)
-          SeenExprs[OldSCEV].push_back(WeakVH(I));
+          SeenExprs[OldSCEV].push_back(WeakVH(&*I));
       }
     }
   }