Index: include/llvm/CodeGen/SelectionDAG.h
===================================================================
--- include/llvm/CodeGen/SelectionDAG.h
+++ include/llvm/CodeGen/SelectionDAG.h
@@ -1240,6 +1240,18 @@
                                 SDValue N1, SDValue N2, bool nuw, bool nsw,
                                 bool exact);
 
+  /// Look up the node specified by ID in CSEMap.  If it exists, return it.  If
+  /// not, return the insertion token that will make insertion faster.  This
+  /// overload is for nodes other than Constant or ConstantFP, use the other one
+  /// for those.
+  SDNode *FindNodeOrInsertPos(const FoldingSetNodeID &ID, void *&InsertPos);
+
+  /// Look up the node specified by ID in CSEMap.  If it exists, return it.  If
+  /// not, return the insertion token that will make insertion faster.  Performs
+  /// additional processing for constant nodes.
+  SDNode *FindNodeOrInsertPos(const FoldingSetNodeID &ID, DebugLoc DL,
+                              void *&InsertPos);
+
   /// List of non-single value types.
   FoldingSet<SDVTListNode> VTListMap;
 
Index: include/llvm/CodeGen/SelectionDAGNodes.h
===================================================================
--- include/llvm/CodeGen/SelectionDAGNodes.h
+++ include/llvm/CodeGen/SelectionDAGNodes.h
@@ -1401,11 +1401,10 @@
 class ConstantSDNode : public SDNode {
   const ConstantInt *Value;
   friend class SelectionDAG;
-  // XXX: DebugLoc is unused intentionally until constant coalescing is resolved
   ConstantSDNode(bool isTarget, bool isOpaque, const ConstantInt *val,
-                 DebugLoc, EVT VT)
+                 DebugLoc DL, EVT VT)
     : SDNode(isTarget ? ISD::TargetConstant : ISD::Constant,
-             0, DebugLoc(), getSDVTList(VT)), Value(val) {
+             0, DL, getSDVTList(VT)), Value(val) {
     SubclassData |= (uint16_t)isOpaque;
   }
 public:
@@ -1430,9 +1429,9 @@
 class ConstantFPSDNode : public SDNode {
   const ConstantFP *Value;
   friend class SelectionDAG;
-  ConstantFPSDNode(bool isTarget, const ConstantFP *val, EVT VT)
+  ConstantFPSDNode(bool isTarget, const ConstantFP *val, DebugLoc DL, EVT VT)
     : SDNode(isTarget ? ISD::TargetConstantFP : ISD::ConstantFP,
-             0, DebugLoc(), getSDVTList(VT)), Value(val) {
+             0, DL, getSDVTList(VT)), Value(val) {
   }
 public:
 
Index: lib/CodeGen/SelectionDAG/SelectionDAG.cpp
===================================================================
--- lib/CodeGen/SelectionDAG/SelectionDAG.cpp
+++ lib/CodeGen/SelectionDAG/SelectionDAG.cpp
@@ -877,7 +877,7 @@
   FoldingSetNodeID ID;
   AddNodeIDNode(ID, N->getOpcode(), N->getVTList(), Ops);
   AddNodeIDCustom(ID, N);
-  SDNode *Node = CSEMap.FindNodeOrInsertPos(ID, InsertPos);
+  SDNode *Node = FindNodeOrInsertPos(ID, N->getDebugLoc(), InsertPos);
   return Node;
 }
 
@@ -895,7 +895,7 @@
   FoldingSetNodeID ID;
   AddNodeIDNode(ID, N->getOpcode(), N->getVTList(), Ops);
   AddNodeIDCustom(ID, N);
-  SDNode *Node = CSEMap.FindNodeOrInsertPos(ID, InsertPos);
+  SDNode *Node = FindNodeOrInsertPos(ID, N->getDebugLoc(), InsertPos);
   return Node;
 }
 
@@ -912,7 +912,7 @@
   FoldingSetNodeID ID;
   AddNodeIDNode(ID, N->getOpcode(), N->getVTList(), Ops);
   AddNodeIDCustom(ID, N);
-  SDNode *Node = CSEMap.FindNodeOrInsertPos(ID, InsertPos);
+  SDNode *Node = FindNodeOrInsertPos(ID, N->getDebugLoc(), InsertPos);
   return Node;
 }
 
@@ -976,6 +976,41 @@
   return N;
 }
 
+SDNode *SelectionDAG::FindNodeOrInsertPos(const FoldingSetNodeID &ID,
+                                          void *&InsertPos) {
+  SDNode *N = CSEMap.FindNodeOrInsertPos(ID, InsertPos);
+  if (N) {
+    switch (N->getOpcode()) {
+    default: break; // Process only regular (non-target) constant nodes.
+    case ISD::Constant:
+    case ISD::ConstantFP:
+      assert(false && "Querying for Constant and ConstantFP nodes requires "
+                      "debug location.  Use another overload.");
+      break;
+    }
+  }
+  return N;
+}
+
+SDNode *SelectionDAG::FindNodeOrInsertPos(const FoldingSetNodeID &ID,
+                                          DebugLoc DL, void *&InsertPos) {
+  SDNode *N = CSEMap.FindNodeOrInsertPos(ID, InsertPos);
+  if (N) {
+    switch (N->getOpcode()) {
+    default: break; // Process only regular (non-target) constant nodes.
+    case ISD::Constant:
+    case ISD::ConstantFP:
+      // Erase debug location from the node if the node is used at several
+      // different places to do not propagate one location to all uses as it
+      // leads to incorrect debug info.
+      if (N->getDebugLoc() != DL)
+        N->setDebugLoc(DebugLoc());
+      break;
+    }
+  }
+  return N;
+}
+
 void SelectionDAG::clear() {
   allnodes_clear();
   OperandAllocator.Reset();
@@ -1179,7 +1214,7 @@
   ID.AddBoolean(isO);
   void *IP = nullptr;
   SDNode *N = nullptr;
-  if ((N = CSEMap.FindNodeOrInsertPos(ID, IP)))
+  if ((N = FindNodeOrInsertPos(ID, DL.getDebugLoc(), IP)))
     if (!VT.isVector())
       return SDValue(N, 0);
 
@@ -1223,12 +1258,13 @@
   ID.AddPointer(&V);
   void *IP = nullptr;
   SDNode *N = nullptr;
-  if ((N = CSEMap.FindNodeOrInsertPos(ID, IP)))
+  if ((N = FindNodeOrInsertPos(ID, DL.getDebugLoc(), IP)))
     if (!VT.isVector())
       return SDValue(N, 0);
 
   if (!N) {
-    N = new (NodeAllocator) ConstantFPSDNode(isTarget, &V, EltVT);
+    N = new (NodeAllocator) ConstantFPSDNode(isTarget, &V, DL.getDebugLoc(),
+                                             EltVT);
     CSEMap.InsertNode(N, IP);
     InsertNode(N);
   }
@@ -1285,7 +1321,7 @@
   ID.AddInteger(TargetFlags);
   ID.AddInteger(GV->getType()->getAddressSpace());
   void *IP = nullptr;
-  if (SDNode *E = CSEMap.FindNodeOrInsertPos(ID, IP))
+  if (SDNode *E = FindNodeOrInsertPos(ID, DL.getDebugLoc(), IP))
     return SDValue(E, 0);
 
   SDNode *N = new (NodeAllocator) GlobalAddressSDNode(Opc, DL.getIROrder(),
@@ -1302,7 +1338,7 @@
   AddNodeIDNode(ID, Opc, getVTList(VT), None);
   ID.AddInteger(FI);
   void *IP = nullptr;
-  if (SDNode *E = CSEMap.FindNodeOrInsertPos(ID, IP))
+  if (SDNode *E = FindNodeOrInsertPos(ID, IP))
     return SDValue(E, 0);
 
   SDNode *N = new (NodeAllocator) FrameIndexSDNode(FI, VT, isTarget);
@@ -1321,7 +1357,7 @@
   ID.AddInteger(JTI);
   ID.AddInteger(TargetFlags);
   void *IP = nullptr;
-  if (SDNode *E = CSEMap.FindNodeOrInsertPos(ID, IP))
+  if (SDNode *E = FindNodeOrInsertPos(ID, IP))
     return SDValue(E, 0);
 
   SDNode *N = new (NodeAllocator) JumpTableSDNode(JTI, VT, isTarget,
@@ -1347,7 +1383,7 @@
   ID.AddPointer(C);
   ID.AddInteger(TargetFlags);
   void *IP = nullptr;
-  if (SDNode *E = CSEMap.FindNodeOrInsertPos(ID, IP))
+  if (SDNode *E = FindNodeOrInsertPos(ID, IP))
     return SDValue(E, 0);
 
   SDNode *N = new (NodeAllocator) ConstantPoolSDNode(isTarget, C, VT, Offset,
@@ -1374,7 +1410,7 @@
   C->addSelectionDAGCSEId(ID);
   ID.AddInteger(TargetFlags);
   void *IP = nullptr;
-  if (SDNode *E = CSEMap.FindNodeOrInsertPos(ID, IP))
+  if (SDNode *E = FindNodeOrInsertPos(ID, IP))
     return SDValue(E, 0);
 
   SDNode *N = new (NodeAllocator) ConstantPoolSDNode(isTarget, C, VT, Offset,
@@ -1392,7 +1428,7 @@
   ID.AddInteger(Offset);
   ID.AddInteger(TargetFlags);
   void *IP = nullptr;
-  if (SDNode *E = CSEMap.FindNodeOrInsertPos(ID, IP))
+  if (SDNode *E = FindNodeOrInsertPos(ID, IP))
     return SDValue(E, 0);
 
   SDNode *N = new (NodeAllocator) TargetIndexSDNode(Index, VT, Offset,
@@ -1407,7 +1443,7 @@
   AddNodeIDNode(ID, ISD::BasicBlock, getVTList(MVT::Other), None);
   ID.AddPointer(MBB);
   void *IP = nullptr;
-  if (SDNode *E = CSEMap.FindNodeOrInsertPos(ID, IP))
+  if (SDNode *E = FindNodeOrInsertPos(ID, IP))
     return SDValue(E, 0);
 
   SDNode *N = new (NodeAllocator) BasicBlockSDNode(MBB);
@@ -1620,7 +1656,7 @@
     ID.AddInteger(MaskVec[i]);
 
   void* IP = nullptr;
-  if (SDNode *E = CSEMap.FindNodeOrInsertPos(ID, IP))
+  if (SDNode *E = FindNodeOrInsertPos(ID, dl.getDebugLoc(), IP))
     return SDValue(E, 0);
 
   // Allocate the mask array for the node out of the BumpPtrAllocator, since
@@ -1662,7 +1698,7 @@
   SDValue Ops[] = { Val, DTy, STy, Rnd, Sat };
   AddNodeIDNode(ID, ISD::CONVERT_RNDSAT, getVTList(VT), Ops);
   void* IP = nullptr;
-  if (SDNode *E = CSEMap.FindNodeOrInsertPos(ID, IP))
+  if (SDNode *E = FindNodeOrInsertPos(ID, dl.getDebugLoc(), IP))
     return SDValue(E, 0);
 
   CvtRndSatSDNode *N = new (NodeAllocator) CvtRndSatSDNode(VT, dl.getIROrder(),
@@ -1678,7 +1714,7 @@
   AddNodeIDNode(ID, ISD::Register, getVTList(VT), None);
   ID.AddInteger(RegNo);
   void *IP = nullptr;
-  if (SDNode *E = CSEMap.FindNodeOrInsertPos(ID, IP))
+  if (SDNode *E = FindNodeOrInsertPos(ID, IP))
     return SDValue(E, 0);
 
   SDNode *N = new (NodeAllocator) RegisterSDNode(RegNo, VT);
@@ -1692,7 +1728,7 @@
   AddNodeIDNode(ID, ISD::RegisterMask, getVTList(MVT::Untyped), None);
   ID.AddPointer(RegMask);
   void *IP = nullptr;
-  if (SDNode *E = CSEMap.FindNodeOrInsertPos(ID, IP))
+  if (SDNode *E = FindNodeOrInsertPos(ID, IP))
     return SDValue(E, 0);
 
   SDNode *N = new (NodeAllocator) RegisterMaskSDNode(RegMask);
@@ -1707,7 +1743,7 @@
   AddNodeIDNode(ID, ISD::EH_LABEL, getVTList(MVT::Other), Ops);
   ID.AddPointer(Label);
   void *IP = nullptr;
-  if (SDNode *E = CSEMap.FindNodeOrInsertPos(ID, IP))
+  if (SDNode *E = FindNodeOrInsertPos(ID, IP))
     return SDValue(E, 0);
 
   SDNode *N = new (NodeAllocator) EHLabelSDNode(dl.getIROrder(),
@@ -1730,7 +1766,7 @@
   ID.AddInteger(Offset);
   ID.AddInteger(TargetFlags);
   void *IP = nullptr;
-  if (SDNode *E = CSEMap.FindNodeOrInsertPos(ID, IP))
+  if (SDNode *E = FindNodeOrInsertPos(ID, IP))
     return SDValue(E, 0);
 
   SDNode *N = new (NodeAllocator) BlockAddressSDNode(Opc, VT, BA, Offset,
@@ -1749,7 +1785,7 @@
   ID.AddPointer(V);
 
   void *IP = nullptr;
-  if (SDNode *E = CSEMap.FindNodeOrInsertPos(ID, IP))
+  if (SDNode *E = FindNodeOrInsertPos(ID, IP))
     return SDValue(E, 0);
 
   SDNode *N = new (NodeAllocator) SrcValueSDNode(V);
@@ -1765,7 +1801,7 @@
   ID.AddPointer(MD);
 
   void *IP = nullptr;
-  if (SDNode *E = CSEMap.FindNodeOrInsertPos(ID, IP))
+  if (SDNode *E = FindNodeOrInsertPos(ID, IP))
     return SDValue(E, 0);
 
   SDNode *N = new (NodeAllocator) MDNodeSDNode(MD);
@@ -1784,7 +1820,7 @@
   ID.AddInteger(DestAS);
 
   void *IP = nullptr;
-  if (SDNode *E = CSEMap.FindNodeOrInsertPos(ID, IP))
+  if (SDNode *E = FindNodeOrInsertPos(ID, dl.getDebugLoc(), IP))
     return SDValue(E, 0);
 
   SDNode *N = new (NodeAllocator) AddrSpaceCastSDNode(dl.getIROrder(),
@@ -2724,7 +2760,7 @@
   FoldingSetNodeID ID;
   AddNodeIDNode(ID, Opcode, getVTList(VT), None);
   void *IP = nullptr;
-  if (SDNode *E = CSEMap.FindNodeOrInsertPos(ID, IP))
+  if (SDNode *E = FindNodeOrInsertPos(ID, DL.getDebugLoc(), IP))
     return SDValue(E, 0);
 
   SDNode *N = new (NodeAllocator) SDNode(Opcode, DL.getIROrder(),
@@ -3059,7 +3095,7 @@
     SDValue Ops[1] = { Operand };
     AddNodeIDNode(ID, Opcode, VTs, Ops);
     void *IP = nullptr;
-    if (SDNode *E = CSEMap.FindNodeOrInsertPos(ID, IP))
+    if (SDNode *E = FindNodeOrInsertPos(ID, DL.getDebugLoc(), IP))
       return SDValue(E, 0);
 
     N = new (NodeAllocator) UnarySDNode(Opcode, DL.getIROrder(),
@@ -3673,7 +3709,7 @@
     if (BinOpHasFlags)
       AddBinaryNodeIDCustom(ID, Opcode, nuw, nsw, exact);
     void *IP = nullptr;
-    if (SDNode *E = CSEMap.FindNodeOrInsertPos(ID, IP))
+    if (SDNode *E = FindNodeOrInsertPos(ID, DL.getDebugLoc(), IP))
       return SDValue(E, 0);
 
     N = GetBinarySDNode(Opcode, DL, VTs, N1, N2, nuw, nsw, exact);
@@ -3776,7 +3812,7 @@
     FoldingSetNodeID ID;
     AddNodeIDNode(ID, Opcode, VTs, Ops);
     void *IP = nullptr;
-    if (SDNode *E = CSEMap.FindNodeOrInsertPos(ID, IP))
+    if (SDNode *E = FindNodeOrInsertPos(ID, DL.getDebugLoc(), IP))
       return SDValue(E, 0);
 
     N = new (NodeAllocator) TernarySDNode(Opcode, DL.getIROrder(),
@@ -4534,7 +4570,7 @@
   AddNodeIDNode(ID, Opcode, VTList, Ops);
   ID.AddInteger(MMO->getPointerInfo().getAddrSpace());
   void* IP = nullptr;
-  if (SDNode *E = CSEMap.FindNodeOrInsertPos(ID, IP)) {
+  if (SDNode *E = FindNodeOrInsertPos(ID, dl.getDebugLoc(), IP)) {
     cast<AtomicSDNode>(E)->refineAlignment(MMO);
     return SDValue(E, 0);
   }
@@ -4739,7 +4775,7 @@
     AddNodeIDNode(ID, Opcode, VTList, Ops);
     ID.AddInteger(MMO->getPointerInfo().getAddrSpace());
     void *IP = nullptr;
-    if (SDNode *E = CSEMap.FindNodeOrInsertPos(ID, IP)) {
+    if (SDNode *E = FindNodeOrInsertPos(ID, dl.getDebugLoc(), IP)) {
       cast<MemIntrinsicSDNode>(E)->refineAlignment(MMO);
       return SDValue(E, 0);
     }
@@ -4861,7 +4897,7 @@
                                      MMO->isInvariant()));
   ID.AddInteger(MMO->getPointerInfo().getAddrSpace());
   void *IP = nullptr;
-  if (SDNode *E = CSEMap.FindNodeOrInsertPos(ID, IP)) {
+  if (SDNode *E = FindNodeOrInsertPos(ID, dl.getDebugLoc(), IP)) {
     cast<LoadSDNode>(E)->refineAlignment(MMO);
     return SDValue(E, 0);
   }
@@ -4969,7 +5005,7 @@
                                      MMO->isNonTemporal(), MMO->isInvariant()));
   ID.AddInteger(MMO->getPointerInfo().getAddrSpace());
   void *IP = nullptr;
-  if (SDNode *E = CSEMap.FindNodeOrInsertPos(ID, IP)) {
+  if (SDNode *E = FindNodeOrInsertPos(ID, dl.getDebugLoc(), IP)) {
     cast<StoreSDNode>(E)->refineAlignment(MMO);
     return SDValue(E, 0);
   }
@@ -5038,7 +5074,7 @@
                                      MMO->isNonTemporal(), MMO->isInvariant()));
   ID.AddInteger(MMO->getPointerInfo().getAddrSpace());
   void *IP = nullptr;
-  if (SDNode *E = CSEMap.FindNodeOrInsertPos(ID, IP)) {
+  if (SDNode *E = FindNodeOrInsertPos(ID, dl.getDebugLoc(), IP)) {
     cast<StoreSDNode>(E)->refineAlignment(MMO);
     return SDValue(E, 0);
   }
@@ -5064,7 +5100,7 @@
   ID.AddInteger(ST->getRawSubclassData());
   ID.AddInteger(ST->getPointerInfo().getAddrSpace());
   void *IP = nullptr;
-  if (SDNode *E = CSEMap.FindNodeOrInsertPos(ID, IP))
+  if (SDNode *E = FindNodeOrInsertPos(ID, dl.getDebugLoc(), IP))
     return SDValue(E, 0);
 
   SDNode *N = new (NodeAllocator) StoreSDNode(Ops, dl.getIROrder(),
@@ -5093,7 +5129,7 @@
                                      MMO->isInvariant()));
   ID.AddInteger(MMO->getPointerInfo().getAddrSpace());
   void *IP = nullptr;
-  if (SDNode *E = CSEMap.FindNodeOrInsertPos(ID, IP)) {
+  if (SDNode *E = FindNodeOrInsertPos(ID, dl.getDebugLoc(), IP)) {
     cast<MaskedLoadSDNode>(E)->refineAlignment(MMO);
     return SDValue(E, 0);
   }
@@ -5120,7 +5156,7 @@
                                      MMO->isNonTemporal(), MMO->isInvariant()));
   ID.AddInteger(MMO->getPointerInfo().getAddrSpace());
   void *IP = nullptr;
-  if (SDNode *E = CSEMap.FindNodeOrInsertPos(ID, IP)) {
+  if (SDNode *E = FindNodeOrInsertPos(ID, dl.getDebugLoc(), IP)) {
     cast<MaskedStoreSDNode>(E)->refineAlignment(MMO);
     return SDValue(E, 0);
   }
@@ -5146,7 +5182,7 @@
                                      MMO->isInvariant()));
   ID.AddInteger(MMO->getPointerInfo().getAddrSpace());
   void *IP = nullptr;
-  if (SDNode *E = CSEMap.FindNodeOrInsertPos(ID, IP)) {
+  if (SDNode *E = FindNodeOrInsertPos(ID, dl.getDebugLoc(), IP)) {
     cast<MaskedGatherSDNode>(E)->refineAlignment(MMO);
     return SDValue(E, 0);
   }
@@ -5169,7 +5205,7 @@
                                      MMO->isInvariant()));
   ID.AddInteger(MMO->getPointerInfo().getAddrSpace());
   void *IP = nullptr;
-  if (SDNode *E = CSEMap.FindNodeOrInsertPos(ID, IP)) {
+  if (SDNode *E = FindNodeOrInsertPos(ID, dl.getDebugLoc(), IP)) {
     cast<MaskedScatterSDNode>(E)->refineAlignment(MMO);
     return SDValue(E, 0);
   }
@@ -5245,7 +5281,7 @@
     AddNodeIDNode(ID, Opcode, VTs, Ops);
     void *IP = nullptr;
 
-    if (SDNode *E = CSEMap.FindNodeOrInsertPos(ID, IP))
+    if (SDNode *E = FindNodeOrInsertPos(ID, DL.getDebugLoc(), IP))
       return SDValue(E, 0);
 
     N = new (NodeAllocator) SDNode(Opcode, DL.getIROrder(), DL.getDebugLoc(),
@@ -5300,7 +5336,7 @@
     FoldingSetNodeID ID;
     AddNodeIDNode(ID, Opcode, VTList, Ops);
     void *IP = nullptr;
-    if (SDNode *E = CSEMap.FindNodeOrInsertPos(ID, IP))
+    if (SDNode *E = FindNodeOrInsertPos(ID, DL.getDebugLoc(), IP))
       return SDValue(E, 0);
 
     if (NumOps == 1) {
@@ -5726,7 +5762,7 @@
   if (VTs.VTs[VTs.NumVTs-1] != MVT::Glue) {
     FoldingSetNodeID ID;
     AddNodeIDNode(ID, Opc, VTs, Ops);
-    if (SDNode *ON = CSEMap.FindNodeOrInsertPos(ID, IP))
+    if (SDNode *ON = FindNodeOrInsertPos(ID, N->getDebugLoc(), IP))
       return UpdadeSDLocOnMergedSDNode(ON, SDLoc(N));
   }
 
@@ -5932,7 +5968,7 @@
     FoldingSetNodeID ID;
     AddNodeIDNode(ID, ~Opcode, VTs, OpsArray);
     IP = nullptr;
-    if (SDNode *E = CSEMap.FindNodeOrInsertPos(ID, IP)) {
+    if (SDNode *E = FindNodeOrInsertPos(ID, DL.getDebugLoc(), IP)) {
       return cast<MachineSDNode>(UpdadeSDLocOnMergedSDNode(E, DL));
     }
   }
@@ -5992,7 +6028,7 @@
     if (isBinOpWithFlags(Opcode))
       AddBinaryNodeIDCustom(ID, nuw, nsw, exact);
     void *IP = nullptr;
-    if (SDNode *E = CSEMap.FindNodeOrInsertPos(ID, IP))
+    if (SDNode *E = FindNodeOrInsertPos(ID, DebugLoc(), IP))
       return E;
   }
   return nullptr;
Index: test/DebugInfo/AArch64/constant-dbgloc.ll
===================================================================
--- test/DebugInfo/AArch64/constant-dbgloc.ll
+++ test/DebugInfo/AArch64/constant-dbgloc.ll
@@ -1,6 +1,4 @@
 ; RUN: llc -filetype=asm %s -o - | FileCheck %s
-; XFAIL: *
-; disabled until constant coalescing is resolved
 
 target datalayout = "e-m:e-p:32:32-i64:64-v128:64:128-a:0:32-n32-S64"
 target triple = "aarch64--linux-gnueabihf"
Index: test/DebugInfo/ARM/constant-dbgloc.ll
===================================================================
--- test/DebugInfo/ARM/constant-dbgloc.ll
+++ test/DebugInfo/ARM/constant-dbgloc.ll
@@ -1,6 +1,4 @@
 ; RUN: llc -filetype=asm %s -o - | FileCheck %s
-; XFAIL: *
-; disabled until constant coalescing is resolved
 
 target datalayout = "e-m:e-p:32:32-i64:64-v128:64:128-a:0:32-n32-S64"
 target triple = "armv7--linux-gnueabihf"
Index: test/DebugInfo/ARM/multiple-constant-uses-drops-dbgloc.ll
===================================================================
--- /dev/null
+++ test/DebugInfo/ARM/multiple-constant-uses-drops-dbgloc.ll
@@ -0,0 +1,54 @@
+; RUN: llc -filetype=asm -asm-verbose=0 < %s | FileCheck %s
+
+; char ch;
+; int b;
+; 
+; void proc (void)
+; {
+;     ch = 'A';
+;     b = 0; // <== this should have correct location
+; }
+
+; CHECK: .loc 1 7 7
+; CHECK: mov  r{{[0-9]}}, #0
+
+target datalayout = "e-m:e-p:32:32-i64:64-v128:64:128-a:0:32-n32-S64"
+target triple = "armv7--linux-gnueabihf"
+
+@ch = common global i8 0, align 1
+@b = common global i32 0, align 4
+
+; Function Attrs: nounwind
+define void @proc() #0 {
+entry:
+  store i8 65, i8* @ch, align 1, !dbg !17
+  store i32 0, i32* @b, align 4, !dbg !18
+  ret void, !dbg !19
+}
+
+attributes #0 = { nounwind "less-precise-fpmad"="false" "no-frame-pointer-elim"="true" "no-frame-pointer-elim-non-leaf" "no-infs-fp-math"="false" "no-nans-fp-math"="false" "stack-protector-buffer-size"="8" "target-cpu"="cortex-a8" "target-features"="+neon,+vfp3" "unsafe-fp-math"="false" "use-soft-float"="false" }
+
+!llvm.dbg.cu = !{!0}
+!llvm.module.flags = !{!12, !13, !14, !15}
+!llvm.ident = !{!16}
+
+!0 = !DICompileUnit(language: DW_LANG_C99, file: !1, producer: "", isOptimized: false, subprograms: !3)
+!1 = !DIFile(filename: "test.c", directory: "/home/user/clang/build")
+!2 = !{}
+!3 = !{!4}
+!4 = !DISubprogram(name: "proc", scope: !1, file: !1, line: 4, type: !5, isLocal: false, isDefinition: true, scopeLine: 5, flags: DIFlagPrototyped, isOptimized: false, function: void ()* @proc, variables: !2)
+!5 = !DISubroutineType(types: !6)
+!6 = !{null}
+!7 = !{!8, !10}
+!8 = !DIGlobalVariable(name: "ch", scope: !0, file: !1, line: 1, type: !9, isLocal: false, isDefinition: true, variable: i8* @ch)
+!9 = !DIBasicType(name: "char", size: 8, align: 8, encoding: DW_ATE_unsigned_char)
+!10 = !DIGlobalVariable(name: "b", scope: !0, file: !1, line: 2, type: !11, isLocal: false, isDefinition: true, variable: i32* @b)
+!11 = !DIBasicType(name: "int", size: 32, align: 32, encoding: DW_ATE_signed)
+!12 = !{i32 2, !"Dwarf Version", i32 4}
+!13 = !{i32 2, !"Debug Info Version", i32 3}
+!14 = !{i32 1, !"wchar_size", i32 4}
+!15 = !{i32 1, !"min_enum_size", i32 4}
+!16 = !{!"clang version 3.7.0 (http://llvm.org/git/clang.git 9b0abb9df531ef7928c8182120e1869affca17d5) (http://llvm.org/git/llvm.git b1e759524dd94f7ce1e24935daed8383927e96c1)"}
+!17 = !DILocation(line: 6, column: 8, scope: !4)
+!18 = !DILocation(line: 7, column: 7, scope: !4)
+!19 = !DILocation(line: 8, column: 1, scope: !4)
Index: test/DebugInfo/ARM/single-constant-use-preserves-dbgloc.ll
===================================================================
--- /dev/null
+++ test/DebugInfo/ARM/single-constant-use-preserves-dbgloc.ll
@@ -0,0 +1,72 @@
+; RUN: llc -filetype=asm -asm-verbose=0 < %s | FileCheck %s
+
+; int main()
+; {
+;     int x = 0;
+;     if (x > 0)
+;         return x;
+;     x = -1; // <== this line should have correct debug location
+;     return -1;
+; }
+
+; CHECK: .loc 1 6 7
+; CHECK: mvn
+
+target datalayout = "e-m:e-p:32:32-i64:64-v128:64:128-a:0:32-n32-S64"
+target triple = "armv7--linux-gnueabihf"
+
+; Function Attrs: nounwind
+define i32 @main() {
+entry:
+  %retval = alloca i32, align 4
+  %x = alloca i32, align 4
+  store i32 0, i32* %retval
+  call void @llvm.dbg.declare(metadata i32* %x, metadata !10, metadata !11), !dbg !12
+  store i32 0, i32* %x, align 4, !dbg !12
+  %0 = load i32, i32* %x, align 4, !dbg !13
+  %cmp = icmp sgt i32 %0, 0, !dbg !15
+  br i1 %cmp, label %if.then, label %if.end, !dbg !16
+
+if.then:                                          ; preds = %entry
+  %1 = load i32, i32* %x, align 4, !dbg !17
+  store i32 %1, i32* %retval, !dbg !18
+  br label %return, !dbg !18
+
+if.end:                                           ; preds = %entry
+  store i32 -1, i32* %x, align 4, !dbg !19
+  store i32 -1, i32* %retval, !dbg !20
+  br label %return, !dbg !20
+
+return:                                           ; preds = %if.end, %if.then
+  %2 = load i32, i32* %retval, !dbg !21
+  ret i32 %2, !dbg !21
+}
+
+; Function Attrs: nounwind readnone
+declare void @llvm.dbg.declare(metadata, metadata, metadata)
+
+!llvm.dbg.cu = !{!0}
+!llvm.module.flags = !{!8, !9}
+
+!0 = !DICompileUnit(language: DW_LANG_C99, file: !1, producer: "", isOptimized: false, subprograms: !3)
+!1 = !DIFile(filename: "test.c", directory: "/home/user/clang/build")
+!2 = !{}
+!3 = !{!4}
+!4 = !DISubprogram(name: "main", scope: !1, file: !1, line: 1, type: !5, isLocal: false, isDefinition: true, scopeLine: 2, isOptimized: false, function: i32 ()* @main, variables: !2)
+!5 = !DISubroutineType(types: !6)
+!6 = !{!7}
+!7 = !DIBasicType(name: "int", size: 32, align: 32, encoding: DW_ATE_signed)
+!8 = !{i32 2, !"Dwarf Version", i32 4}
+!9 = !{i32 2, !"Debug Info Version", i32 3}
+!10 = !DILocalVariable(tag: DW_TAG_auto_variable, name: "x", scope: !4, file: !1, line: 3, type: !7)
+!11 = !DIExpression()
+!12 = !DILocation(line: 3, column: 9, scope: !4)
+!13 = !DILocation(line: 4, column: 9, scope: !14)
+!14 = distinct !DILexicalBlock(scope: !4, file: !1, line: 4, column: 9)
+!15 = !DILocation(line: 4, column: 11, scope: !14)
+!16 = !DILocation(line: 4, column: 9, scope: !4)
+!17 = !DILocation(line: 5, column: 13, scope: !14)
+!18 = !DILocation(line: 5, column: 9, scope: !14)
+!19 = !DILocation(line: 6, column: 7, scope: !4)
+!20 = !DILocation(line: 7, column: 5, scope: !4)
+!21 = !DILocation(line: 8, column: 1, scope: !4)
Index: test/DebugInfo/constant-sdnodes-have-dbg-location.ll
===================================================================
--- test/DebugInfo/constant-sdnodes-have-dbg-location.ll
+++ test/DebugInfo/constant-sdnodes-have-dbg-location.ll
@@ -1,7 +1,5 @@
 ; RUN: llc -debug < %s 2>&1 | FileCheck %s
 ; REQUIRES: asserts
-; XFAIL: *
-; disabled until constant coalescing is resolved
 
 ; CHECK: 0x{{[0-9,a-f]+}}: i32 = Constant<-1>test.c:4:5
 
Index: test/DebugInfo/constantfp-sdnodes-have-dbg-location.ll
===================================================================
--- /dev/null
+++ test/DebugInfo/constantfp-sdnodes-have-dbg-location.ll
@@ -0,0 +1,24 @@
+; RUN: llc -debug < %s 2>&1 | FileCheck %s
+; REQUIRES: asserts
+
+; CHECK: 0x{{[0-9,a-f]+}}: f64 = ConstantFP<1.500000e+00>test.c:3:5
+
+define double @f() {
+entry:
+  ret double 1.500000e+00, !dbg !10
+}
+
+!llvm.dbg.cu = !{!0}
+!llvm.module.flags = !{!8, !9}
+
+!0 = !DICompileUnit(language: DW_LANG_C99, file: !1, producer: "", isOptimized: false, subprograms: !3)
+!1 = !DIFile(filename: "test.c", directory: "/home/user/clang-llvm/build")
+!2 = !{}
+!3 = !{!4}
+!4 = !DISubprogram(name: "f", scope: !1, file: !1, line: 1, type: !5, isLocal: false, isDefinition: true, scopeLine: 2, flags: DIFlagPrototyped, isOptimized: false, function: double ()* @f, variables: !2)
+!5 = !DISubroutineType(types: !6)
+!6 = !{!7}
+!7 = !DIBasicType(name: "double", size: 64, align: 64, encoding: DW_ATE_float)
+!8 = !{i32 2, !"Dwarf Version", i32 4}
+!9 = !{i32 2, !"Debug Info Version", i32 3}
+!10 = !DILocation(line: 3, column: 5, scope: !4)