[SLP] Vectorize jumbled memory loads.

Summary:
This patch tries to vectorize loads of consecutive memory accesses, accessed
in non-consecutive or jumbled way. An earlier attempt was made with patch D26905
which was reverted back due to some basic issue with representing the 'use mask' of
jumbled accesses.

This patch fixes the mask representation by recording the 'use mask' in the usertree entry.

Change-Id: I9fe7f5045f065d84c126fa307ef6ebe0787296df

Reviewers: mkuper, loladiro, Ayal, zvi, danielcdh

Reviewed By: Ayal

Subscribers: mgrang, dcaballe, hans, mzolotukhin

Differential Revision: https://reviews.llvm.org/D36130

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@320548 91177308-0d34-0410-b5e6-96231b3b80d8

2 files changed, 266 insertions, 83 deletions

diff --git a/lib/Analysis/LoopAccessAnalysis.cpp b/lib/Analysis/LoopAccessAnalysis.cpp
index e141d6c58b6..ed8e5e8cc48 100644
--- a/lib/Analysis/LoopAccessAnalysis.cpp
+++ b/lib/Analysis/LoopAccessAnalysis.cpp
@@ -1107,6 +1107,77 @@ static unsigned getAddressSpaceOperand(Value *I) {
   return -1;
 }
 
+// TODO:This API can be improved by using the permutation of given width as the
+// accesses are entered into the map.
+bool llvm::sortLoadAccesses(ArrayRef<Value *> VL, const DataLayout &DL,
+                           ScalarEvolution &SE,
+                           SmallVectorImpl<Value *> &Sorted,
+                           SmallVectorImpl<unsigned> *Mask) {
+  SmallVector<std::pair<int64_t, Value *>, 4> OffValPairs;
+  OffValPairs.reserve(VL.size());
+  Sorted.reserve(VL.size());
+
+  // Walk over the pointers, and map each of them to an offset relative to
+  // first pointer in the array.
+  Value *Ptr0 = getPointerOperand(VL[0]);
+  const SCEV *Scev0 = SE.getSCEV(Ptr0);
+  Value *Obj0 = GetUnderlyingObject(Ptr0, DL);
+  PointerType *PtrTy = dyn_cast<PointerType>(Ptr0->getType());
+  uint64_t Size = DL.getTypeAllocSize(PtrTy->getElementType());
+
+  for (auto *Val : VL) {
+    // The only kind of access we care about here is load.
+    if (!isa<LoadInst>(Val))
+      return false;
+
+    Value *Ptr = getPointerOperand(Val);
+    assert(Ptr && "Expected value to have a pointer operand.");
+    // If a pointer refers to a different underlying object, bail - the
+    // pointers are by definition incomparable.
+    Value *CurrObj = GetUnderlyingObject(Ptr, DL);
+    if (CurrObj != Obj0)
+      return false;
+
+    const SCEVConstant *Diff =
+        dyn_cast<SCEVConstant>(SE.getMinusSCEV(SE.getSCEV(Ptr), Scev0));
+    // The pointers may not have a constant offset from each other, or SCEV
+    // may just not be smart enough to figure out they do. Regardless,
+    // there's nothing we can do.
+    if (!Diff || static_cast<unsigned>(Diff->getAPInt().abs().getSExtValue()) >
+                     (VL.size() - 1) * Size)
+      return false;
+
+    OffValPairs.emplace_back(Diff->getAPInt().getSExtValue(), Val);
+  }
+  SmallVector<unsigned, 4> UseOrder(VL.size());
+  for (unsigned i = 0; i < VL.size(); i++) {
+    UseOrder[i] = i;
+  }
+
+  // Sort the memory accesses and keep the order of their uses in UseOrder.
+  std::sort(UseOrder.begin(), UseOrder.end(),
+            [&OffValPairs](unsigned Left, unsigned Right) {
+            return OffValPairs[Left].first < OffValPairs[Right].first;
+            });
+
+  for (unsigned i = 0; i < VL.size(); i++)
+    Sorted.emplace_back(OffValPairs[UseOrder[i]].second);
+
+  // Sort UseOrder to compute the Mask.
+  if (Mask) {
+    Mask->reserve(VL.size());
+    for (unsigned i = 0; i < VL.size(); i++)
+      Mask->emplace_back(i);
+    std::sort(Mask->begin(), Mask->end(),
+              [&UseOrder](unsigned Left, unsigned Right) {
+              return UseOrder[Left] < UseOrder[Right];
+              });
+  }
+
+  return true;
+}
+
+
 /// Returns true if the memory operations \p A and \p B are consecutive.
 bool llvm::isConsecutiveAccess(Value *A, Value *B, const DataLayout &DL,
                                ScalarEvolution &SE, bool CheckType) {
diff --git a/lib/Transforms/Vectorize/SLPVectorizer.cpp b/lib/Transforms/Vectorize/SLPVectorizer.cpp
index d30c1063c0d..9b35f35e870 100644
--- a/lib/Transforms/Vectorize/SLPVectorizer.cpp
+++ b/lib/Transforms/Vectorize/SLPVectorizer.cpp
@@ -646,17 +646,23 @@ private:
   int getEntryCost(TreeEntry *E);
 
   /// This is the recursive part of buildTree.
-  void buildTree_rec(ArrayRef<Value *> Roots, unsigned Depth, int);
+  void buildTree_rec(ArrayRef<Value *> Roots, unsigned Depth, int UserIndx = -1,
+                     int OpdNum = 0);
 
   /// \returns True if the ExtractElement/ExtractValue instructions in VL can
   /// be vectorized to use the original vector (or aggregate "bitcast" to a vector).
   bool canReuseExtract(ArrayRef<Value *> VL, Value *OpValue) const;
 
-  /// Vectorize a single entry in the tree.
-  Value *vectorizeTree(TreeEntry *E);
+  /// Vectorize a single entry in the tree.\p OpdNum indicate the ordinality of
+  /// operand corrsponding to this tree entry \p E for the user tree entry
+  /// indicated by \p UserIndx.
+  //  In other words, "E == TreeEntry[UserIndx].getOperand(OpdNum)".
+  Value *vectorizeTree(TreeEntry *E, int OpdNum = 0, int UserIndx = -1);
 
-  /// Vectorize a single entry in the tree, starting in \p VL.
-  Value *vectorizeTree(ArrayRef<Value *> VL);
+  /// Vectorize a single entry in the tree, starting in \p VL.\p OpdNum indicate
+  /// the ordinality of operand corrsponding to the \p VL of scalar values for the
+  /// user indicated by \p UserIndx this \p VL feeds into.
+  Value *vectorizeTree(ArrayRef<Value *> VL, int OpdNum = 0, int UserIndx = -1);
 
   /// \returns the pointer to the vectorized value if \p VL is already
   /// vectorized, or NULL. They may happen in cycles.
@@ -702,6 +708,16 @@ private:
       return std::equal(VL.begin(), VL.end(), Scalars.begin());
     }
 
+    /// \returns true if the scalars in VL are found in this tree entry.
+    bool isFoundJumbled(ArrayRef<Value *> VL, const DataLayout &DL,
+        ScalarEvolution &SE) const {
+      assert(VL.size() == Scalars.size() && "Invalid size");
+      SmallVector<Value *, 8> List;
+      if (!sortLoadAccesses(VL, DL, SE, List))
+        return false;
+      return std::equal(List.begin(), List.end(), Scalars.begin());
+    }
+
     /// A vector of scalars.
     ValueList Scalars;
 
@@ -711,6 +727,14 @@ private:
     /// Do we need to gather this sequence ?
     bool NeedToGather = false;
 
+    /// Records optional shuffle mask for the uses of jumbled memory accesses.
+    /// For example, a non-empty ShuffleMask[1] represents the permutation of
+    /// lanes that operand #1 of this vectorized instruction should undergo
+    /// before feeding this vectorized instruction, whereas an empty
+    /// ShuffleMask[0] indicates that the lanes of operand #0 of this vectorized
+    /// instruction need not be permuted at all.
+    SmallVector<SmallVector<unsigned, 4>, 2> ShuffleMask;
+
     /// Points back to the VectorizableTree.
     ///
     /// Only used for Graphviz right now.  Unfortunately GraphTrait::NodeRef has
@@ -726,12 +750,31 @@ private:
 
   /// Create a new VectorizableTree entry.
   TreeEntry *newTreeEntry(ArrayRef<Value *> VL, bool Vectorized,
-                          int &UserTreeIdx) {
+                          int &UserTreeIdx, const InstructionsState &S,
+                          ArrayRef<unsigned> ShuffleMask = None,
+                          int OpdNum = 0) {
+    assert((!Vectorized || S.Opcode != 0) &&
+           "Vectorized TreeEntry without opcode");
     VectorizableTree.emplace_back(VectorizableTree);
+
     int idx = VectorizableTree.size() - 1;
     TreeEntry *Last = &VectorizableTree[idx];
     Last->Scalars.insert(Last->Scalars.begin(), VL.begin(), VL.end());
     Last->NeedToGather = !Vectorized;
+
+    TreeEntry *UserTreeEntry = nullptr;
+    if (UserTreeIdx != -1)
+      UserTreeEntry = &VectorizableTree[UserTreeIdx];
+
+    if (UserTreeEntry && !ShuffleMask.empty()) {
+      if ((unsigned)OpdNum >= UserTreeEntry->ShuffleMask.size())
+        UserTreeEntry->ShuffleMask.resize(OpdNum + 1);
+      assert(UserTreeEntry->ShuffleMask[OpdNum].empty() &&
+             "Mask already present");
+      using mask = SmallVector<unsigned, 4>;
+      mask tempMask(ShuffleMask.begin(), ShuffleMask.end());
+      UserTreeEntry->ShuffleMask[OpdNum] = tempMask;
+    }
     if (Vectorized) {
       for (int i = 0, e = VL.size(); i != e; ++i) {
         assert(!getTreeEntry(VL[i]) && "Scalar already in tree!");
@@ -1384,34 +1427,34 @@ void BoUpSLP::buildTree(ArrayRef<Value *> Roots,
 }
 
 void BoUpSLP::buildTree_rec(ArrayRef<Value *> VL, unsigned Depth,
-                            int UserTreeIdx) {
+                            int UserTreeIdx, int OpdNum) {
   assert((allConstant(VL) || allSameType(VL)) && "Invalid types!");
 
   InstructionsState S = getSameOpcode(VL);
   if (Depth == RecursionMaxDepth) {
     DEBUG(dbgs() << "SLP: Gathering due to max recursion depth.\n");
-    newTreeEntry(VL, false, UserTreeIdx);
+    newTreeEntry(VL, false, UserTreeIdx, S);
     return;
   }
 
   // Don't handle vectors.
   if (S.OpValue->getType()->isVectorTy()) {
     DEBUG(dbgs() << "SLP: Gathering due to vector type.\n");
-    newTreeEntry(VL, false, UserTreeIdx);
+    newTreeEntry(VL, false, UserTreeIdx, S);
     return;
   }
 
   if (StoreInst *SI = dyn_cast<StoreInst>(S.OpValue))
     if (SI->getValueOperand()->getType()->isVectorTy()) {
       DEBUG(dbgs() << "SLP: Gathering due to store vector type.\n");
-      newTreeEntry(VL, false, UserTreeIdx);
+      newTreeEntry(VL, false, UserTreeIdx, S);
       return;
     }
 
   // If all of the operands are identical or constant we have a simple solution.
   if (allConstant(VL) || isSplat(VL) || !allSameBlock(VL) || !S.Opcode) {
     DEBUG(dbgs() << "SLP: Gathering due to C,S,B,O. \n");
-    newTreeEntry(VL, false, UserTreeIdx);
+    newTreeEntry(VL, false, UserTreeIdx, S);
     return;
   }
 
@@ -1423,7 +1466,7 @@ void BoUpSLP::buildTree_rec(ArrayRef<Value *> VL, unsigned Depth,
     if (EphValues.count(VL[i])) {
       DEBUG(dbgs() << "SLP: The instruction (" << *VL[i] <<
             ") is ephemeral.\n");
-      newTreeEntry(VL, false, UserTreeIdx);
+      newTreeEntry(VL, false, UserTreeIdx, S);
       return;
     }
   }
@@ -1434,7 +1477,7 @@ void BoUpSLP::buildTree_rec(ArrayRef<Value *> VL, unsigned Depth,
       DEBUG(dbgs() << "SLP: \tChecking bundle: " << *VL[i] << ".\n");
       if (E->Scalars[i] != VL[i]) {
         DEBUG(dbgs() << "SLP: Gathering due to partial overlap.\n");
-        newTreeEntry(VL, false, UserTreeIdx);
+        newTreeEntry(VL, false, UserTreeIdx, S);
         return;
       }
     }
@@ -1453,7 +1496,7 @@ void BoUpSLP::buildTree_rec(ArrayRef<Value *> VL, unsigned Depth,
     if (getTreeEntry(I)) {
       DEBUG(dbgs() << "SLP: The instruction (" << *VL[i] <<
             ") is already in tree.\n");
-      newTreeEntry(VL, false, UserTreeIdx);
+      newTreeEntry(VL, false, UserTreeIdx, S);
       return;
     }
   }
@@ -1463,7 +1506,7 @@ void BoUpSLP::buildTree_rec(ArrayRef<Value *> VL, unsigned Depth,
   for (unsigned i = 0, e = VL.size(); i != e; ++i) {
     if (MustGather.count(VL[i])) {
       DEBUG(dbgs() << "SLP: Gathering due to gathered scalar.\n");
-      newTreeEntry(VL, false, UserTreeIdx);
+      newTreeEntry(VL, false, UserTreeIdx, S);
       return;
     }
   }
@@ -1477,7 +1520,7 @@ void BoUpSLP::buildTree_rec(ArrayRef<Value *> VL, unsigned Depth,
     // Don't go into unreachable blocks. They may contain instructions with
     // dependency cycles which confuse the final scheduling.
     DEBUG(dbgs() << "SLP: bundle in unreachable block.\n");
-    newTreeEntry(VL, false, UserTreeIdx);
+    newTreeEntry(VL, false, UserTreeIdx, S);
     return;
   }
 
@@ -1486,7 +1529,7 @@ void BoUpSLP::buildTree_rec(ArrayRef<Value *> VL, unsigned Depth,
     for (unsigned j = i + 1; j < e; ++j)
       if (VL[i] == VL[j]) {
         DEBUG(dbgs() << "SLP: Scalar used twice in bundle.\n");
-        newTreeEntry(VL, false, UserTreeIdx);
+        newTreeEntry(VL, false, UserTreeIdx, S);
         return;
       }
 
@@ -1501,7 +1544,7 @@ void BoUpSLP::buildTree_rec(ArrayRef<Value *> VL, unsigned Depth,
     assert((!BS.getScheduleData(VL0) ||
             !BS.getScheduleData(VL0)->isPartOfBundle()) &&
            "tryScheduleBundle should cancelScheduling on failure");
-    newTreeEntry(VL, false, UserTreeIdx);
+    newTreeEntry(VL, false, UserTreeIdx, S);
     return;
   }
   DEBUG(dbgs() << "SLP: We are able to schedule this bundle.\n");
@@ -1520,12 +1563,12 @@ void BoUpSLP::buildTree_rec(ArrayRef<Value *> VL, unsigned Depth,
           if (Term) {
             DEBUG(dbgs() << "SLP: Need to swizzle PHINodes (TerminatorInst use).\n");
             BS.cancelScheduling(VL, VL0);
-            newTreeEntry(VL, false, UserTreeIdx);
+            newTreeEntry(VL, false, UserTreeIdx, S);
             return;
           }
         }
 
-      newTreeEntry(VL, true, UserTreeIdx);
+      newTreeEntry(VL, true, UserTreeIdx, S);
       DEBUG(dbgs() << "SLP: added a vector of PHINodes.\n");
 
       for (unsigned i = 0, e = PH->getNumIncomingValues(); i < e; ++i) {
@@ -1535,7 +1578,7 @@ void BoUpSLP::buildTree_rec(ArrayRef<Value *> VL, unsigned Depth,
           Operands.push_back(cast<PHINode>(j)->getIncomingValueForBlock(
               PH->getIncomingBlock(i)));
 
-        buildTree_rec(Operands, Depth + 1, UserTreeIdx);
+        buildTree_rec(Operands, Depth + 1, UserTreeIdx, i);
       }
       return;
     }
@@ -1547,7 +1590,7 @@ void BoUpSLP::buildTree_rec(ArrayRef<Value *> VL, unsigned Depth,
       } else {
         BS.cancelScheduling(VL, VL0);
       }
-      newTreeEntry(VL, Reuse, UserTreeIdx);
+      newTreeEntry(VL, Reuse, UserTreeIdx, S);
       return;
     }
     case Instruction::Load: {
@@ -1562,7 +1605,7 @@ void BoUpSLP::buildTree_rec(ArrayRef<Value *> VL, unsigned Depth,
       if (DL->getTypeSizeInBits(ScalarTy) !=
           DL->getTypeAllocSizeInBits(ScalarTy)) {
         BS.cancelScheduling(VL, VL0);
-        newTreeEntry(VL, false, UserTreeIdx);
+        newTreeEntry(VL, false, UserTreeIdx, S);
         DEBUG(dbgs() << "SLP: Gathering loads of non-packed type.\n");
         return;
       }
@@ -1573,15 +1616,13 @@ void BoUpSLP::buildTree_rec(ArrayRef<Value *> VL, unsigned Depth,
         LoadInst *L = cast<LoadInst>(VL[i]);
         if (!L->isSimple()) {
           BS.cancelScheduling(VL, VL0);
-          newTreeEntry(VL, false, UserTreeIdx);
+          newTreeEntry(VL, false, UserTreeIdx, S);
           DEBUG(dbgs() << "SLP: Gathering non-simple loads.\n");
           return;
         }
       }
 
       // Check if the loads are consecutive, reversed, or neither.
-      // TODO: What we really want is to sort the loads, but for now, check
-      // the two likely directions.
       bool Consecutive = true;
       bool ReverseConsecutive = true;
       for (unsigned i = 0, e = VL.size() - 1; i < e; ++i) {
@@ -1595,7 +1636,7 @@ void BoUpSLP::buildTree_rec(ArrayRef<Value *> VL, unsigned Depth,
 
       if (Consecutive) {
         ++NumLoadsWantToKeepOrder;
-        newTreeEntry(VL, true, UserTreeIdx);
+        newTreeEntry(VL, true, UserTreeIdx, S);
         DEBUG(dbgs() << "SLP: added a vector of loads.\n");
         return;
       }
@@ -1609,15 +1650,41 @@ void BoUpSLP::buildTree_rec(ArrayRef<Value *> VL, unsigned Depth,
             break;
           }
 
-      BS.cancelScheduling(VL, VL0);
-      newTreeEntry(VL, false, UserTreeIdx);
-
       if (ReverseConsecutive) {
-        ++NumLoadsWantToChangeOrder;
         DEBUG(dbgs() << "SLP: Gathering reversed loads.\n");
-      } else {
-        DEBUG(dbgs() << "SLP: Gathering non-consecutive loads.\n");
+        ++NumLoadsWantToChangeOrder;
+        BS.cancelScheduling(VL, VL0);
+        newTreeEntry(VL, false, UserTreeIdx, S);
+        return;
+      }
+
+      if (VL.size() > 2) {
+        bool ShuffledLoads = true;
+        SmallVector<Value *, 8> Sorted;
+        SmallVector<unsigned, 4> Mask;
+        if (sortLoadAccesses(VL, *DL, *SE, Sorted, &Mask)) {
+          auto NewVL = makeArrayRef(Sorted.begin(), Sorted.end());
+          for (unsigned i = 0, e = NewVL.size() - 1; i < e; ++i) {
+            if (!isConsecutiveAccess(NewVL[i], NewVL[i + 1], *DL, *SE)) {
+              ShuffledLoads = false;
+              break;
+            }
+          }
+          // TODO: Tracking how many load wants to have arbitrary shuffled order
+          // would be usefull.
+          if (ShuffledLoads) {
+            DEBUG(dbgs() << "SLP: added a vector of loads which needs "
+                            "permutation of loaded lanes.\n");
+            newTreeEntry(NewVL, true, UserTreeIdx, S,
+                         makeArrayRef(Mask.begin(), Mask.end()), OpdNum);
+            return;
+          }
+        }
       }
+
+      DEBUG(dbgs() << "SLP: Gathering non-consecutive loads.\n");
+      BS.cancelScheduling(VL, VL0);
+      newTreeEntry(VL, false, UserTreeIdx, S);
       return;
     }
     case Instruction::ZExt:
@@ -1637,12 +1704,12 @@ void BoUpSLP::buildTree_rec(ArrayRef<Value *> VL, unsigned Depth,
         Type *Ty = cast<Instruction>(VL[i])->getOperand(0)->getType();
         if (Ty != SrcTy || !isValidElementType(Ty)) {
           BS.cancelScheduling(VL, VL0);
-          newTreeEntry(VL, false, UserTreeIdx);
+          newTreeEntry(VL, false, UserTreeIdx, S);
           DEBUG(dbgs() << "SLP: Gathering casts with different src types.\n");
           return;
         }
       }
-      newTreeEntry(VL, true, UserTreeIdx);
+      newTreeEntry(VL, true, UserTreeIdx, S);
       DEBUG(dbgs() << "SLP: added a vector of casts.\n");
 
       for (unsigned i = 0, e = VL0->getNumOperands(); i < e; ++i) {
@@ -1651,7 +1718,7 @@ void BoUpSLP::buildTree_rec(ArrayRef<Value *> VL, unsigned Depth,
         for (Value *j : VL)
           Operands.push_back(cast<Instruction>(j)->getOperand(i));
 
-        buildTree_rec(Operands, Depth + 1, UserTreeIdx);
+        buildTree_rec(Operands, Depth + 1, UserTreeIdx, i);
       }
       return;
     }
@@ -1665,13 +1732,13 @@ void BoUpSLP::buildTree_rec(ArrayRef<Value *> VL, unsigned Depth,
         if (Cmp->getPredicate() != P0 ||
             Cmp->getOperand(0)->getType() != ComparedTy) {
           BS.cancelScheduling(VL, VL0);
-          newTreeEntry(VL, false, UserTreeIdx);
+          newTreeEntry(VL, false, UserTreeIdx, S);
           DEBUG(dbgs() << "SLP: Gathering cmp with different predicate.\n");
           return;
         }
       }
 
-      newTreeEntry(VL, true, UserTreeIdx);
+      newTreeEntry(VL, true, UserTreeIdx, S);
       DEBUG(dbgs() << "SLP: added a vector of compares.\n");
 
       for (unsigned i = 0, e = VL0->getNumOperands(); i < e; ++i) {
@@ -1680,7 +1747,7 @@ void BoUpSLP::buildTree_rec(ArrayRef<Value *> VL, unsigned Depth,
         for (Value *j : VL)
           Operands.push_back(cast<Instruction>(j)->getOperand(i));
 
-        buildTree_rec(Operands, Depth + 1, UserTreeIdx);
+        buildTree_rec(Operands, Depth + 1, UserTreeIdx, i);
       }
       return;
     }
@@ -1703,7 +1770,7 @@ void BoUpSLP::buildTree_rec(ArrayRef<Value *> VL, unsigned Depth,
     case Instruction::And:
     case Instruction::Or:
     case Instruction::Xor:
-      newTreeEntry(VL, true, UserTreeIdx);
+      newTreeEntry(VL, true, UserTreeIdx, S);
       DEBUG(dbgs() << "SLP: added a vector of bin op.\n");
 
       // Sort operands of the instructions so that each side is more likely to
@@ -1712,7 +1779,7 @@ void BoUpSLP::buildTree_rec(ArrayRef<Value *> VL, unsigned Depth,
         ValueList Left, Right;
         reorderInputsAccordingToOpcode(S.Opcode, VL, Left, Right);
         buildTree_rec(Left, Depth + 1, UserTreeIdx);
-        buildTree_rec(Right, Depth + 1, UserTreeIdx);
+        buildTree_rec(Right, Depth + 1, UserTreeIdx, 1);
         return;
       }
 
@@ -1722,7 +1789,7 @@ void BoUpSLP::buildTree_rec(ArrayRef<Value *> VL, unsigned Depth,
         for (Value *j : VL)
           Operands.push_back(cast<Instruction>(j)->getOperand(i));
 
-        buildTree_rec(Operands, Depth + 1, UserTreeIdx);
+        buildTree_rec(Operands, Depth + 1, UserTreeIdx, i);
       }
       return;
 
@@ -1732,7 +1799,7 @@ void BoUpSLP::buildTree_rec(ArrayRef<Value *> VL, unsigned Depth,
         if (cast<Instruction>(VL[j])->getNumOperands() != 2) {
           DEBUG(dbgs() << "SLP: not-vectorizable GEP (nested indexes).\n");
           BS.cancelScheduling(VL, VL0);
-          newTreeEntry(VL, false, UserTreeIdx);
+          newTreeEntry(VL, false, UserTreeIdx, S);
           return;
         }
       }
@@ -1745,7 +1812,7 @@ void BoUpSLP::buildTree_rec(ArrayRef<Value *> VL, unsigned Depth,
         if (Ty0 != CurTy) {
           DEBUG(dbgs() << "SLP: not-vectorizable GEP (different types).\n");
           BS.cancelScheduling(VL, VL0);
-          newTreeEntry(VL, false, UserTreeIdx);
+          newTreeEntry(VL, false, UserTreeIdx, S);
           return;
         }
       }
@@ -1757,12 +1824,12 @@ void BoUpSLP::buildTree_rec(ArrayRef<Value *> VL, unsigned Depth,
           DEBUG(
               dbgs() << "SLP: not-vectorizable GEP (non-constant indexes).\n");
           BS.cancelScheduling(VL, VL0);
-          newTreeEntry(VL, false, UserTreeIdx);
+          newTreeEntry(VL, false, UserTreeIdx, S);
           return;
         }
       }
 
-      newTreeEntry(VL, true, UserTreeIdx);
+      newTreeEntry(VL, true, UserTreeIdx, S);
       DEBUG(dbgs() << "SLP: added a vector of GEPs.\n");
       for (unsigned i = 0, e = 2; i < e; ++i) {
         ValueList Operands;
@@ -1770,7 +1837,7 @@ void BoUpSLP::buildTree_rec(ArrayRef<Value *> VL, unsigned Depth,
         for (Value *j : VL)
           Operands.push_back(cast<Instruction>(j)->getOperand(i));
 
-        buildTree_rec(Operands, Depth + 1, UserTreeIdx);
+        buildTree_rec(Operands, Depth + 1, UserTreeIdx, i);
       }
       return;
     }
@@ -1779,12 +1846,12 @@ void BoUpSLP::buildTree_rec(ArrayRef<Value *> VL, unsigned Depth,
       for (unsigned i = 0, e = VL.size() - 1; i < e; ++i)
         if (!isConsecutiveAccess(VL[i], VL[i + 1], *DL, *SE)) {
           BS.cancelScheduling(VL, VL0);
-          newTreeEntry(VL, false, UserTreeIdx);
+          newTreeEntry(VL, false, UserTreeIdx, S);
           DEBUG(dbgs() << "SLP: Non-consecutive store.\n");
           return;
         }
 
-      newTreeEntry(VL, true, UserTreeIdx);
+      newTreeEntry(VL, true, UserTreeIdx, S);
       DEBUG(dbgs() << "SLP: added a vector of stores.\n");
 
       ValueList Operands;
@@ -1802,7 +1869,7 @@ void BoUpSLP::buildTree_rec(ArrayRef<Value *> VL, unsigned Depth,
       Intrinsic::ID ID = getVectorIntrinsicIDForCall(CI, TLI);
       if (!isTriviallyVectorizable(ID)) {
         BS.cancelScheduling(VL, VL0);
-        newTreeEntry(VL, false, UserTreeIdx);
+        newTreeEntry(VL, false, UserTreeIdx, S);
         DEBUG(dbgs() << "SLP: Non-vectorizable call.\n");
         return;
       }
@@ -1816,7 +1883,7 @@ void BoUpSLP::buildTree_rec(ArrayRef<Value *> VL, unsigned Depth,
             getVectorIntrinsicIDForCall(CI2, TLI) != ID ||
             !CI->hasIdenticalOperandBundleSchema(*CI2)) {
           BS.cancelScheduling(VL, VL0);
-          newTreeEntry(VL, false, UserTreeIdx);
+          newTreeEntry(VL, false, UserTreeIdx, S);
           DEBUG(dbgs() << "SLP: mismatched calls:" << *CI << "!=" << *VL[i]
                        << "\n");
           return;
@@ -1827,7 +1894,7 @@ void BoUpSLP::buildTree_rec(ArrayRef<Value *> VL, unsigned Depth,
           Value *A1J = CI2->getArgOperand(1);
           if (A1I != A1J) {
             BS.cancelScheduling(VL, VL0);
-            newTreeEntry(VL, false, UserTreeIdx);
+            newTreeEntry(VL, false, UserTreeIdx, S);
             DEBUG(dbgs() << "SLP: mismatched arguments in call:" << *CI
                          << " argument "<< A1I<<"!=" << A1J
                          << "\n");
@@ -1840,14 +1907,14 @@ void BoUpSLP::buildTree_rec(ArrayRef<Value *> VL, unsigned Depth,
                         CI->op_begin() + CI->getBundleOperandsEndIndex(),
                         CI2->op_begin() + CI2->getBundleOperandsStartIndex())) {
           BS.cancelScheduling(VL, VL0);
-          newTreeEntry(VL, false, UserTreeIdx);
+          newTreeEntry(VL, false, UserTreeIdx, S);
           DEBUG(dbgs() << "SLP: mismatched bundle operands in calls:" << *CI << "!="
                        << *VL[i] << '\n');
           return;
         }
       }
 
-      newTreeEntry(VL, true, UserTreeIdx);
+      newTreeEntry(VL, true, UserTreeIdx, S);
       for (unsigned i = 0, e = CI->getNumArgOperands(); i != e; ++i) {
         ValueList Operands;
         // Prepare the operand vector.
@@ -1855,7 +1922,7 @@ void BoUpSLP::buildTree_rec(ArrayRef<Value *> VL, unsigned Depth,
           CallInst *CI2 = dyn_cast<CallInst>(j);
           Operands.push_back(CI2->getArgOperand(i));
         }
-        buildTree_rec(Operands, Depth + 1, UserTreeIdx);
+        buildTree_rec(Operands, Depth + 1, UserTreeIdx, i);
       }
       return;
     }
@@ -1864,11 +1931,11 @@ void BoUpSLP::buildTree_rec(ArrayRef<Value *> VL, unsigned Depth,
       // then do not vectorize this instruction.
       if (!S.IsAltShuffle) {
         BS.cancelScheduling(VL, VL0);
-        newTreeEntry(VL, false, UserTreeIdx);
+        newTreeEntry(VL, false, UserTreeIdx, S);
         DEBUG(dbgs() << "SLP: ShuffleVector are not vectorized.\n");
         return;
       }
-      newTreeEntry(VL, true, UserTreeIdx);
+      newTreeEntry(VL, true, UserTreeIdx, S);
       DEBUG(dbgs() << "SLP: added a ShuffleVector op.\n");
 
       // Reorder operands if reordering would enable vectorization.
@@ -1876,7 +1943,7 @@ void BoUpSLP::buildTree_rec(ArrayRef<Value *> VL, unsigned Depth,
         ValueList Left, Right;
         reorderAltShuffleOperands(S.Opcode, VL, Left, Right);
         buildTree_rec(Left, Depth + 1, UserTreeIdx);
-        buildTree_rec(Right, Depth + 1, UserTreeIdx);
+        buildTree_rec(Right, Depth + 1, UserTreeIdx, 1);
         return;
       }
 
@@ -1886,13 +1953,13 @@ void BoUpSLP::buildTree_rec(ArrayRef<Value *> VL, unsigned Depth,
         for (Value *j : VL)
           Operands.push_back(cast<Instruction>(j)->getOperand(i));
 
-        buildTree_rec(Operands, Depth + 1, UserTreeIdx);
+        buildTree_rec(Operands, Depth + 1, UserTreeIdx, i);
       }
       return;
 
     default:
       BS.cancelScheduling(VL, VL0);
-      newTreeEntry(VL, false, UserTreeIdx);
+      newTreeEntry(VL, false, UserTreeIdx, S);
       DEBUG(dbgs() << "SLP: Gathering unknown instruction.\n");
       return;
   }
@@ -2730,12 +2797,20 @@ Value *BoUpSLP::alreadyVectorized(ArrayRef<Value *> VL, Value *OpValue) const {
   return nullptr;
 }
 
-Value *BoUpSLP::vectorizeTree(ArrayRef<Value *> VL) {
+Value *BoUpSLP::vectorizeTree(ArrayRef<Value *> VL, int OpdNum, int UserIndx) {
   InstructionsState S = getSameOpcode(VL);
   if (S.Opcode) {
     if (TreeEntry *E = getTreeEntry(S.OpValue)) {
-      if (E->isSame(VL))
-        return vectorizeTree(E);
+      TreeEntry *UserTreeEntry = nullptr;
+      if (UserIndx != -1)
+        UserTreeEntry = &VectorizableTree[UserIndx];
+
+      if (E->isSame(VL) ||
+          (UserTreeEntry &&
+           (unsigned)OpdNum < UserTreeEntry->ShuffleMask.size() &&
+           !UserTreeEntry->ShuffleMask[OpdNum].empty() &&
+           E->isFoundJumbled(VL, *DL, *SE)))
+        return vectorizeTree(E, OpdNum, UserIndx);
     }
   }
 
@@ -2747,9 +2822,10 @@ Value *BoUpSLP::vectorizeTree(ArrayRef<Value *> VL) {
   return Gather(VL, VecTy);
 }
 
-Value *BoUpSLP::vectorizeTree(TreeEntry *E) {
+Value *BoUpSLP::vectorizeTree(TreeEntry *E, int OpdNum, int UserIndx) {
   IRBuilder<>::InsertPointGuard Guard(Builder);
 
+  TreeEntry *UserTreeEntry = nullptr;
   if (E->VectorizedValue) {
     DEBUG(dbgs() << "SLP: Diamond merged for " << *E->Scalars[0] << ".\n");
     return E->VectorizedValue;
@@ -2769,6 +2845,10 @@ Value *BoUpSLP::vectorizeTree(TreeEntry *E) {
     return V;
   }
 
+  assert(ScalarToTreeEntry.count(E->Scalars[0]) &&
+         "Expected user tree entry, missing!");
+  int CurrIndx = ScalarToTreeEntry[E->Scalars[0]];
+
   unsigned ShuffleOrOp = S.IsAltShuffle ?
            (unsigned) Instruction::ShuffleVector : S.Opcode;
   switch (ShuffleOrOp) {
@@ -2798,7 +2878,7 @@ Value *BoUpSLP::vectorizeTree(TreeEntry *E) {
 
         Builder.SetInsertPoint(IBB->getTerminator());
         Builder.SetCurrentDebugLocation(PH->getDebugLoc());
-        Value *Vec = vectorizeTree(Operands);
+        Value *Vec = vectorizeTree(Operands, i, CurrIndx);
         NewPhi->addIncoming(Vec, IBB);
       }
 
@@ -2851,7 +2931,7 @@ Value *BoUpSLP::vectorizeTree(TreeEntry *E) {
 
       setInsertPointAfterBundle(E->Scalars, VL0);
 
-      Value *InVec = vectorizeTree(INVL);
+      Value *InVec = vectorizeTree(INVL, 0, CurrIndx);
 
       if (Value *V = alreadyVectorized(E->Scalars, VL0))
         return V;
@@ -2872,8 +2952,8 @@ Value *BoUpSLP::vectorizeTree(TreeEntry *E) {
 
       setInsertPointAfterBundle(E->Scalars, VL0);
 
-      Value *L = vectorizeTree(LHSV);
-      Value *R = vectorizeTree(RHSV);
+      Value *L = vectorizeTree(LHSV, 0, CurrIndx);
+      Value *R = vectorizeTree(RHSV, 1, CurrIndx);
 
       if (Value *V = alreadyVectorized(E->Scalars, VL0))
         return V;
@@ -2900,9 +2980,9 @@ Value *BoUpSLP::vectorizeTree(TreeEntry *E) {
 
       setInsertPointAfterBundle(E->Scalars, VL0);
 
-      Value *Cond = vectorizeTree(CondVec);
-      Value *True = vectorizeTree(TrueVec);
-      Value *False = vectorizeTree(FalseVec);
+      Value *Cond = vectorizeTree(CondVec, 0, CurrIndx);
+      Value *True = vectorizeTree(TrueVec, 1, CurrIndx);
+      Value *False = vectorizeTree(FalseVec, 2, CurrIndx);
 
       if (Value *V = alreadyVectorized(E->Scalars, VL0))
         return V;
@@ -2943,8 +3023,8 @@ Value *BoUpSLP::vectorizeTree(TreeEntry *E) {
 
       setInsertPointAfterBundle(E->Scalars, VL0);
 
-      Value *LHS = vectorizeTree(LHSVL);
-      Value *RHS = vectorizeTree(RHSVL);
+      Value *LHS = vectorizeTree(LHSVL, 0, CurrIndx);
+      Value *RHS = vectorizeTree(RHSVL, 1, CurrIndx);
 
       if (Value *V = alreadyVectorized(E->Scalars, VL0))
         return V;
@@ -2965,7 +3045,20 @@ Value *BoUpSLP::vectorizeTree(TreeEntry *E) {
       // sink them all the way down past store instructions.
       setInsertPointAfterBundle(E->Scalars, VL0);
 
-      LoadInst *LI = cast<LoadInst>(VL0);
+      if (UserIndx != -1)
+        UserTreeEntry = &VectorizableTree[UserIndx];
+
+      bool isJumbled = false;
+      LoadInst *LI = NULL;
+      if (UserTreeEntry &&
+          (unsigned)OpdNum < UserTreeEntry->ShuffleMask.size() &&
+          !UserTreeEntry->ShuffleMask[OpdNum].empty()) {
+        isJumbled = true;
+        LI = cast<LoadInst>(E->Scalars[0]);
+      } else {
+        LI = cast<LoadInst>(VL0);
+      }
+
       Type *ScalarLoadTy = LI->getType();
       unsigned AS = LI->getPointerAddressSpace();
 
@@ -2987,7 +3080,21 @@ Value *BoUpSLP::vectorizeTree(TreeEntry *E) {
       LI->setAlignment(Alignment);
       E->VectorizedValue = LI;
       ++NumVectorInstructions;
-      return propagateMetadata(LI, E->Scalars);
+      propagateMetadata(LI, E->Scalars);
+
+      if (isJumbled) {
+        SmallVector<Constant *, 8> Mask;
+        for (unsigned LaneEntry : UserTreeEntry->ShuffleMask[OpdNum])
+          Mask.push_back(Builder.getInt32(LaneEntry));
+        // Generate shuffle for jumbled memory access
+        Value *Undef = UndefValue::get(VecTy);
+        Value *Shuf = Builder.CreateShuffleVector((Value *)LI, Undef,
+                                                  ConstantVector::get(Mask));
+        E->VectorizedValue = Shuf;
+        ++NumVectorInstructions;
+        return Shuf;
+      }
+      return LI;
     }
     case Instruction::Store: {
       StoreInst *SI = cast<StoreInst>(VL0);
@@ -3000,7 +3107,7 @@ Value *BoUpSLP::vectorizeTree(TreeEntry *E) {
 
       setInsertPointAfterBundle(E->Scalars, VL0);
 
-      Value *VecValue = vectorizeTree(ScalarStoreValues);
+      Value *VecValue = vectorizeTree(ScalarStoreValues, 0, CurrIndx);
       Value *ScalarPtr = SI->getPointerOperand();
       Value *VecPtr = Builder.CreateBitCast(ScalarPtr, VecTy->getPointerTo(AS));
       StoreInst *S = Builder.CreateStore(VecValue, VecPtr);
@@ -3026,7 +3133,7 @@ Value *BoUpSLP::vectorizeTree(TreeEntry *E) {
       for (Value *V : E->Scalars)
         Op0VL.push_back(cast<GetElementPtrInst>(V)->getOperand(0));
 
-      Value *Op0 = vectorizeTree(Op0VL);
+      Value *Op0 = vectorizeTree(Op0VL, 0, CurrIndx);
 
       std::vector<Value *> OpVecs;
       for (int j = 1, e = cast<GetElementPtrInst>(VL0)->getNumOperands(); j < e;
@@ -3035,7 +3142,7 @@ Value *BoUpSLP::vectorizeTree(TreeEntry *E) {
         for (Value *V : E->Scalars)
           OpVL.push_back(cast<GetElementPtrInst>(V)->getOperand(j));
 
-        Value *OpVec = vectorizeTree(OpVL);
+        Value *OpVec = vectorizeTree(OpVL, j, CurrIndx);
         OpVecs.push_back(OpVec);
       }
 
@@ -3074,7 +3181,7 @@ Value *BoUpSLP::vectorizeTree(TreeEntry *E) {
           OpVL.push_back(CEI->getArgOperand(j));
         }
 
-        Value *OpVec = vectorizeTree(OpVL);
+        Value *OpVec = vectorizeTree(OpVL, j, CurrIndx);
         DEBUG(dbgs() << "SLP: OpVec[" << j << "]: " << *OpVec << "\n");
         OpVecs.push_back(OpVec);
       }
@@ -3105,8 +3212,8 @@ Value *BoUpSLP::vectorizeTree(TreeEntry *E) {
       reorderAltShuffleOperands(S.Opcode, E->Scalars, LHSVL, RHSVL);
       setInsertPointAfterBundle(E->Scalars, VL0);
 
-      Value *LHS = vectorizeTree(LHSVL);
-      Value *RHS = vectorizeTree(RHSVL);
+      Value *LHS = vectorizeTree(LHSVL, 0, CurrIndx);
+      Value *RHS = vectorizeTree(RHSVL, 1, CurrIndx);
 
       if (Value *V = alreadyVectorized(E->Scalars, VL0))
         return V;
@@ -3206,9 +3313,14 @@ BoUpSLP::vectorizeTree(ExtraValueToDebugLocsMap &ExternallyUsedValues) {
       continue;
     TreeEntry *E = getTreeEntry(Scalar);
     assert(E && "Invalid scalar");
-    assert(!E->NeedToGather && "Extracting from a gather list");
+    assert((!E->NeedToGather) && "Extracting from a gather list");
 
-    Value *Vec = E->VectorizedValue;
+    Value *Vec = dyn_cast<ShuffleVectorInst>(E->VectorizedValue);
+    if (Vec && dyn_cast<LoadInst>(cast<Instruction>(Vec)->getOperand(0))) {
+      Vec = cast<Instruction>(E->VectorizedValue)->getOperand(0);
+    } else {
+      Vec = E->VectorizedValue;
+    }
     assert(Vec && "Can't find vectorizable value");
 
     Value *Lane = Builder.getInt32(ExternalUse.Lane);