3 files changed, 11 insertions, 5 deletions
diff --git a/lib/Transforms/InstCombine/InstructionCombining.cpp b/lib/Transforms/InstCombine/InstructionCombining.cpp
index be7d43bbcf2c3..f530ee1246e8c 100644
--- a/lib/Transforms/InstCombine/InstructionCombining.cpp
+++ b/lib/Transforms/InstCombine/InstructionCombining.cpp
@@ -3065,9 +3065,11 @@ static bool TryToSinkInstruction(Instruction *I, BasicBlock *DestBlock) {
       I->isTerminator())
     return false;
 
-  // Do not sink alloca instructions out of the entry block.
-  if (isa<AllocaInst>(I) && I->getParent() ==
-        &DestBlock->getParent()->getEntryBlock())
+  // Do not sink static or dynamic alloca instructions. Static allocas must
+  // remain in the entry block, and dynamic allocas must not be sunk in between
+  // a stacksave / stackrestore pair, which would incorrectly shorten its
+  // lifetime.
+  if (isa<AllocaInst>(I))
     return false;
 
   // Do not sink into catchswitch blocks.
diff --git a/lib/Transforms/Scalar/SROA.cpp b/lib/Transforms/Scalar/SROA.cpp
index eab77cf4cda9b..68ca6c47c8f1a 100644
--- a/lib/Transforms/Scalar/SROA.cpp
+++ b/lib/Transforms/Scalar/SROA.cpp
@@ -3031,7 +3031,10 @@ private:
     ConstantInt *Size =
         ConstantInt::get(cast<IntegerType>(II.getArgOperand(0)->getType()),
                          NewEndOffset - NewBeginOffset);
-    Value *Ptr = getNewAllocaSlicePtr(IRB, OldPtr->getType());
+    // Lifetime intrinsics always expect an i8* so directly get such a pointer
+    // for the new alloca slice.
+    Type *PointerTy = IRB.getInt8PtrTy(OldPtr->getType()->getPointerAddressSpace());
+    Value *Ptr = getNewAllocaSlicePtr(IRB, PointerTy);
     Value *New;
     if (II.getIntrinsicID() == Intrinsic::lifetime_start)
       New = IRB.CreateLifetimeStart(Ptr, Size);
diff --git a/lib/Transforms/Vectorize/SLPVectorizer.cpp b/lib/Transforms/Vectorize/SLPVectorizer.cpp
index 2e856a7e6802e..a07fffe9b98b9 100644
--- a/lib/Transforms/Vectorize/SLPVectorizer.cpp
+++ b/lib/Transforms/Vectorize/SLPVectorizer.cpp
@@ -1468,8 +1468,9 @@ void BoUpSLP::buildTree_rec(ArrayRef<Value *> VL, unsigned Depth,
 
   // If any of the scalars is marked as a value that needs to stay scalar, then
   // we need to gather the scalars.
+  // The reduction nodes (stored in UserIgnoreList) also should stay scalar.
   for (unsigned i = 0, e = VL.size(); i != e; ++i) {
-    if (MustGather.count(VL[i])) {
+    if (MustGather.count(VL[i]) || is_contained(UserIgnoreList, VL[i])) {
       LLVM_DEBUG(dbgs() << "SLP: Gathering due to gathered scalar.\n");
       newTreeEntry(VL, false, UserTreeIdx);
       return;