Index: llvm/lib/CodeGen/LiveDebugValues.cpp
===================================================================
--- llvm/lib/CodeGen/LiveDebugValues.cpp
+++ llvm/lib/CodeGen/LiveDebugValues.cpp
@@ -114,6 +114,7 @@
 
 class LiveDebugValues : public MachineFunctionPass {
 private:
+  MachineFunction *CurrentMF;
   const TargetRegisterInfo *TRI;
   const TargetInstrInfo *TII;
   const TargetFrameLowering *TFI;
@@ -200,13 +201,13 @@
 
   /// A pair of debug variable and value location.
   struct VarLoc {
-    // The location at which a spilled variable resides. It consists of a
-    // register and an offset.
+    // The location at which a spilled variable resides. It consists of an
+    // offset and a size, and is implicitly against the frame register.
     struct SpillLoc {
-      unsigned SpillBase;
       int SpillOffset;
+      unsigned int SpillSize;
       bool operator==(const SpillLoc &Other) const {
-        return SpillBase == Other.SpillBase && SpillOffset == Other.SpillOffset;
+        return SpillOffset == Other.SpillOffset && SpillSize == Other.SpillSize;
       }
     };
 
@@ -321,12 +322,33 @@
 
     /// Take the variable described by DBG_VALUE MI, and create a VarLoc
     /// locating it in the specified spill location.
-    static VarLoc CreateSpillLoc(const MachineInstr &MI, unsigned SpillBase,
-                                 int SpillOffset, LexicalScopes &LS) {
+    static VarLoc CreateSpillLoc(const MachineInstr &MI, SpillLoc Loc,
+                                 LexicalScopes &LS) {
       VarLoc VL(MI, LS);
       assert(VL.Kind == RegisterKind);
       VL.Kind = SpillLocKind;
-      VL.Loc.SpillLocation = {SpillBase, SpillOffset};
+      VL.Loc.SpillLocation = Loc;
+      return VL;
+    }
+
+    /// Restore a location from a spill. The DBG_VALUE that this location is
+    /// rooted on could either be a register location that's been spilt in a
+    /// transfer; or it could be a DBG_VALUE of a stack location, created by
+    /// the register allocator. Determine which, and create a register
+    /// location representing the restore.
+    static VarLoc CreateRestoreLoc(const MachineInstr &MI, LexicalScopes &LS,
+                                   unsigned NewReg) {
+      VarLoc VL(MI, LS);
+      assert((VL.Kind == RegisterKind || VL.Kind == SpillLocKind) &&
+             "Unexpected type of DBG_VALUE restored");
+
+      // If this was a spilt register-loc, we can use the expression from the
+      // original DBG_VALUE. Likewise, for spill locations, as the spill
+      // offset will not have been baked into the DIExpression yet, the
+      // expression can be re-used. We need only point the location to the
+      // new register.
+      VL.Kind = RegisterKind;
+      VL.Loc.RegNo = NewReg;
       return VL;
     }
 
@@ -336,7 +358,6 @@
     /// have been several transfers ago.
     MachineInstr *BuildDbgValue(MachineFunction &MF) const {
       const DebugLoc &DbgLoc = MI.getDebugLoc();
-      bool Indirect = MI.isIndirectDebugValue();
       const auto &IID = MI.getDesc();
       const DILocalVariable *Var = MI.getDebugVariable();
       const DIExpression *DIExpr = MI.getDebugExpression();
@@ -347,25 +368,34 @@
         // expression. The register location of such DBG_VALUE is always the one
         // from the entry DBG_VALUE, it does not matter if the entry value was
         // copied in to another register due to some optimizations.
-        return BuildMI(MF, DbgLoc, IID, Indirect, MI.getOperand(0).getReg(),
-                       Var, Expr);
+        return BuildMI(MF, DbgLoc, IID, false, MI.getOperand(0).getReg(), Var,
+                       Expr);
       case RegisterKind:
         // Register locations are like the source DBG_VALUE, but with the
         // register number from this VarLoc.
-        return BuildMI(MF, DbgLoc, IID, Indirect, Loc.RegNo, Var, DIExpr);
+        return BuildMI(MF, DbgLoc, IID, false, Loc.RegNo, Var, DIExpr);
       case SpillLocKind: {
         // Spills are indirect DBG_VALUEs, with a base register and offset.
         // Use the original DBG_VALUEs expression to build the spilt location
-        // on top of. FIXME: spill locations created before this pass runs
-        // are not recognized, and not handled here.
-        auto *SpillExpr = DIExpression::prepend(
-            DIExpr, DIExpression::ApplyOffset, Loc.SpillLocation.SpillOffset);
-        unsigned Base = Loc.SpillLocation.SpillBase;
-        return BuildMI(MF, DbgLoc, IID, true, Base, Var, SpillExpr);
+        // on top of.
+
+        auto *TRI = MF.getSubtarget().getRegisterInfo();
+        unsigned FrameReg = TRI->getFrameRegister(MF);
+        if (DIExpr->isImplicit()) {
+          SmallVector<uint64_t, 2> Ops = {dwarf::DW_OP_deref_size,
+                                          Loc.SpillLocation.SpillSize};
+          DIExpr = DIExpression::prependOpcodes(DIExpr, Ops);
+          DIExpr = DIExpression::prepend(DIExpr, DIExpression::ApplyOffset,
+                                         Loc.SpillLocation.SpillOffset);
+        } else {
+          DIExpr = DIExpression::prepend(DIExpr, DIExpression::DerefAfter,
+                                         Loc.SpillLocation.SpillOffset);
+        }
+        return BuildMI(MF, DbgLoc, IID, false, FrameReg, Var, DIExpr);
       }
       case ImmediateKind: {
         MachineOperand MO = MI.getOperand(0);
-        return BuildMI(MF, DbgLoc, IID, Indirect, MO, Var, DIExpr);
+        return BuildMI(MF, DbgLoc, IID, false, MO, Var, DIExpr);
       }
       case EntryValueBackupKind:
       case EntryValueCopyBackupKind:
@@ -414,7 +444,8 @@
 
 #if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
     // TRI can be null.
-    void dump(const TargetRegisterInfo *TRI, raw_ostream &Out = dbgs()) const {
+    void dump(const MachineFunction *MF, raw_ostream &Out = dbgs()) const {
+      const TargetRegisterInfo *TRI = MF->getSubtarget().getRegisterInfo();
       dbgs() << "VarLoc(";
       switch (Kind) {
       case RegisterKind:
@@ -424,7 +455,7 @@
         dbgs() << printReg(Loc.RegNo, TRI);
         break;
       case SpillLocKind:
-        dbgs() << printReg(Loc.SpillLocation.SpillBase, TRI);
+        dbgs() << printReg(TRI->getFrameRegister(*MF), TRI);
         dbgs() << "[" << Loc.SpillLocation.SpillOffset << "]";
         break;
       case ImmediateKind:
@@ -566,7 +597,7 @@
                                                   unsigned &Reg);
   /// Given a spill instruction, extract the register and offset used to
   /// address the spill location in a target independent way.
-  VarLoc::SpillLoc extractSpillBaseRegAndOffset(const MachineInstr &MI);
+  VarLoc::SpillLoc extractSpillLocation(const MachineInstr &MI);
   void insertTransferDebugPair(MachineInstr &MI, OpenRangesSet &OpenRanges,
                                TransferMap &Transfers, VarLocMap &VarLocIDs,
                                unsigned OldVarID, TransferKind Kind,
@@ -603,6 +634,10 @@
             SmallPtrSetImpl<const MachineBasicBlock *> &ArtificialBlocks,
             VarLocInMBB &PendingInLocs);
 
+  /// Reduce any DBG_VALUE with a stack-slot index in its 1st operand into
+  /// an operation on the frame pointer.
+  void rewriteStackLocs(MachineFunction &MF);
+
   /// Create DBG_VALUE insts for inlocs that have been propagated but
   /// had their instruction creation deferred.
   void flushPendingLocs(VarLocInMBB &PendingInLocs, VarLocMap &VarLocIDs);
@@ -781,7 +816,7 @@
       const VarLoc &VL = VarLocIDs[VLL];
       Out << " Var: " << VL.Var.getVar()->getName();
       Out << " MI: ";
-      VL.dump(TRI, Out);
+      VL.dump(&MF, Out);
     }
   }
   Out << "\n";
@@ -789,7 +824,7 @@
 #endif
 
 LiveDebugValues::VarLoc::SpillLoc
-LiveDebugValues::extractSpillBaseRegAndOffset(const MachineInstr &MI) {
+LiveDebugValues::extractSpillLocation(const MachineInstr &MI) {
   assert(MI.hasOneMemOperand() &&
          "Spill instruction does not have exactly one memory operand?");
   auto MMOI = MI.memoperands_begin();
@@ -800,7 +835,8 @@
   const MachineBasicBlock *MBB = MI.getParent();
   unsigned Reg;
   int Offset = TFI->getFrameIndexReference(*MBB->getParent(), FI, Reg);
-  return {Reg, Offset};
+  (void)Reg;
+  return {Offset, (unsigned)(*MMOI)->getSize()};
 }
 
 /// Try to salvage the debug entry value if we encounter a new debug value
@@ -890,8 +926,21 @@
   }
 
   unsigned ID;
-  if (isDbgValueDescribedByReg(MI) || MI.getOperand(0).isImm() ||
-      MI.getOperand(0).isFPImm() || MI.getOperand(0).isCImm()) {
+
+  unsigned FrameReg = TRI->getFrameRegister(*MI.getMF());
+  if (MI.isIndirectDebugValue() && MI.getOperand(0).isReg() &&
+      MI.getOperand(0).getReg() == FrameReg) {
+    // This is a spill. Its offset should be in the "indirect" operand.
+    unsigned Reg;
+    int64_t FrameIdx = MI.getOperand(1).getImm();
+    auto &MF = *MI.getMF();
+    int64_t Offset = TFI->getFrameIndexReference(MF, FrameIdx, Reg);
+    unsigned Size = MF.getFrameInfo().getObjectSize(FrameIdx);
+    VarLoc VL = VarLoc::CreateSpillLoc(MI, {(int)Offset, Size}, LS);
+    ID = VarLocIDs.insert(VL);
+    OpenRanges.insert(ID, VL);
+  } else if (isDbgValueDescribedByReg(MI) || MI.getOperand(0).isImm() ||
+             MI.getOperand(0).isFPImm() || MI.getOperand(0).isCImm()) {
     // Use normal VarLoc constructor for registers and immediates.
     VarLoc VL(MI, LS);
     // End all previous ranges of VL.Var.
@@ -974,20 +1023,19 @@
     ProcessVarLoc(VL);
     LLVM_DEBUG({
       dbgs() << "Creating VarLoc for register copy:";
-      VL.dump(TRI);
+      VL.dump(CurrentMF);
     });
     return;
   }
   case TransferKind::TransferSpill: {
     // Create a DBG_VALUE instruction to describe the Var in its spilled
     // location.
-    VarLoc::SpillLoc SpillLocation = extractSpillBaseRegAndOffset(MI);
-    VarLoc VL = VarLoc::CreateSpillLoc(*DebugInstr, SpillLocation.SpillBase,
-                                       SpillLocation.SpillOffset, LS);
+    VarLoc::SpillLoc SpillLocation = extractSpillLocation(MI);
+    VarLoc VL = VarLoc::CreateSpillLoc(*DebugInstr, SpillLocation, LS);
     ProcessVarLoc(VL);
     LLVM_DEBUG({
       dbgs() << "Creating VarLoc for spill:";
-      VL.dump(TRI);
+      VL.dump(CurrentMF);
     });
     return;
   }
@@ -996,11 +1044,11 @@
            "No register supplied when handling a restore of a debug value");
     // DebugInstr refers to the pre-spill location, therefore we can reuse
     // its expression.
-    VarLoc VL = VarLoc::CreateCopyLoc(*DebugInstr, LS, NewReg);
+    VarLoc VL = VarLoc::CreateRestoreLoc(*DebugInstr, LS, NewReg);
     ProcessVarLoc(VL);
     LLVM_DEBUG({
       dbgs() << "Creating VarLoc for restore:";
-      VL.dump(TRI);
+      VL.dump(CurrentMF);
     });
     return;
   }
@@ -1112,7 +1160,7 @@
   // operand.
   if (MI.getRestoreSize(TII)) {
     Reg = MI.getOperand(0).getReg();
-    return extractSpillBaseRegAndOffset(MI);
+    return extractSpillLocation(MI);
   }
   return None;
 }
@@ -1140,7 +1188,7 @@
   // will have changed.
   VarLocSet KillSet;
   if (isSpillInstruction(MI, MF)) {
-    Loc = extractSpillBaseRegAndOffset(MI);
+    Loc = extractSpillLocation(MI);
     for (unsigned ID : OpenRanges.getVarLocs()) {
       const VarLoc &VL = VarLocIDs[ID];
       if (VL.Kind == VarLoc::SpillLocKind && VL.Loc.SpillLocation == *Loc) {
@@ -1276,7 +1324,7 @@
                   : OpenRanges.getVarLocs()) {
     // Copy OpenRanges to OutLocs, if not already present.
     dbgs() << "Add to OutLocs in MBB #" << CurMBB->getNumber() << ":  ";
-    VarLocIDs[ID].dump(TRI);
+    VarLocIDs[ID].dump(CurrentMF);
   });
   VarLocSet &VLS = OutLocs[CurMBB];
   Changed = VLS != OpenRanges.getVarLocs();
@@ -1460,6 +1508,42 @@
   return Changed;
 }
 
+void LiveDebugValues::rewriteStackLocs(MachineFunction &MF) {
+  for (auto &MBB : MF) {
+    for (auto &MI : MBB) {
+      if (!MI.isDebugValue())
+        continue;
+
+      // Examine only DBG_VALUEs with frame-indexes in the second operand.
+      if (!MI.getOperand(1).isImm())
+        continue;
+
+      // Fetch frame index details, un-set indirect field.
+      unsigned Reg;
+      int64_t FrameIdx = MI.getOperand(1).getImm();
+      int64_t Offset = TFI->getFrameIndexReference(*MI.getMF(), FrameIdx, Reg);
+      unsigned Size = MF.getFrameInfo().getObjectSize(FrameIdx);
+      MI.getOperand(1).ChangeToRegister(0, false);
+
+      const DIExpression *DIExpr = MI.getDebugExpression();
+
+      // Prepend the correct kind of deref onto the expression: big endian
+      // machines want to know the size when dealing with implicit locations.
+      if (DIExpr->isImplicit()) {
+        SmallVector<uint64_t, 2> Ops = {dwarf::DW_OP_deref_size, Size};
+        DIExpr = DIExpression::prependOpcodes(DIExpr, Ops);
+      } else {
+        SmallVector<uint64_t, 1> Ops = {dwarf::DW_OP_deref};
+        DIExpr = DIExpression::prependOpcodes(DIExpr, Ops);
+      }
+
+      // Prepend the stack offset and attach the stack-location expression.
+      DIExpr = DIExpression::prepend(DIExpr, DIExpression::ApplyOffset, Offset);
+      MI.getOperand(3).setMetadata(DIExpr);
+    }
+  }
+}
+
 void LiveDebugValues::flushPendingLocs(VarLocInMBB &PendingInLocs,
                                        VarLocMap &VarLocIDs) {
   // PendingInLocs records all locations propagated into blocks, which have
@@ -1702,6 +1786,12 @@
   // that now.
   flushPendingLocs(PendingInLocs, VarLocIDs);
 
+  // Input DBG_VALUEs that refer to stack spills must be rewritten in terms
+  // of the frame register and expression calculations. This must happen
+  // last, to avoid VarLocs creating new DBG_VALUEs based on expressions
+  // that have stack spill information in them.
+  rewriteStackLocs(MF);
+
   LLVM_DEBUG(printVarLocInMBB(MF, OutLocs, VarLocIDs, "Final OutLocs", dbgs()));
   LLVM_DEBUG(printVarLocInMBB(MF, InLocs, VarLocIDs, "Final InLocs", dbgs()));
   return Changed;
@@ -1717,6 +1807,7 @@
       DICompileUnit::NoDebug)
     return false;
 
+  CurrentMF = &MF;
   TRI = MF.getSubtarget().getRegisterInfo();
   TII = MF.getSubtarget().getInstrInfo();
   TFI = MF.getSubtarget().getFrameLowering();
Index: llvm/lib/CodeGen/LiveDebugVariables.cpp
===================================================================
--- llvm/lib/CodeGen/LiveDebugVariables.cpp
+++ llvm/lib/CodeGen/LiveDebugVariables.cpp
@@ -1301,19 +1301,11 @@
              ->isValidLocationForIntrinsic(getDebugLoc()) &&
          "Expected inlined-at fields to agree");
 
-  // If the location was spilled, the new DBG_VALUE will be indirect. If the
-  // original DBG_VALUE was indirect, we need to add DW_OP_deref to indicate
-  // that the original virtual register was a pointer. Also, add the stack slot
-  // offset for the spilled register to the expression.
-  const DIExpression *Expr = Expression;
-  if (Spilled)
-    Expr = DIExpression::prepend(Expr, DIExpression::ApplyOffset, SpillOffset);
-
   assert((!Spilled || MO.isFI()) && "a spilled location must be a frame index");
 
   do {
-    BuildMI(*MBB, I, getDebugLoc(), TII.get(TargetOpcode::DBG_VALUE),
-            Spilled, MO, Variable, Expr);
+    BuildMI(*MBB, I, getDebugLoc(), TII.get(TargetOpcode::DBG_VALUE), Spilled,
+            MO, Variable, Expression);
 
     // Continue and insert DBG_VALUES after every redefinition of register
     // associated with the debug value within the range
Index: llvm/lib/CodeGen/PrologEpilogInserter.cpp
===================================================================
--- llvm/lib/CodeGen/PrologEpilogInserter.cpp
+++ llvm/lib/CodeGen/PrologEpilogInserter.cpp
@@ -1208,7 +1208,6 @@
                          "operand of a DBG_VALUE machine instruction");
         unsigned Reg;
         unsigned FrameIdx = MI.getOperand(0).getIndex();
-        unsigned Size = MF.getFrameInfo().getObjectSize(FrameIdx);
 
         int64_t Offset =
             TFI->getFrameIndexReference(MF, FrameIdx, Reg);
@@ -1217,26 +1216,24 @@
 
         const DIExpression *DIExpr = MI.getDebugExpression();
 
+        // If this is an indirect debug value, store the frame offset in
+        // the "indirect" field, and let LiveDebugValues lower it to a
+        // DIExpression later. This makes it easier for LiveDebugValues to
+        // recognise and deal with spills/restores.
+        if (MI.isIndirectDebugValue()) {
+          MI.getOperand(1).setImm(FrameIdx);
+          continue;
+        }
+
         // If we have a direct DBG_VALUE, and its location expression isn't
         // currently complex, then adding an offset will morph it into a
         // complex location that is interpreted as being a memory address.
         // This changes a pointer-valued variable to dereference that pointer,
         // which is incorrect. Fix by adding DW_OP_stack_value.
         unsigned PrependFlags = DIExpression::ApplyOffset;
-        if (!MI.isIndirectDebugValue() && !DIExpr->isComplex())
+        if (!DIExpr->isComplex())
           PrependFlags |= DIExpression::StackValue;
 
-        // If we have DBG_VALUE that is indirect and has a Implicit location
-        // expression need to insert a deref before prepending a Memory
-        // location expression. Also after doing this we change the DBG_VALUE
-        // to be direct.
-        if (MI.isIndirectDebugValue() && DIExpr->isImplicit()) {
-          SmallVector<uint64_t, 2> Ops = {dwarf::DW_OP_deref_size, Size};
-          bool WithStackValue = true;
-          DIExpr = DIExpression::prependOpcodes(DIExpr, Ops, WithStackValue);
-          // Make the DBG_VALUE direct.
-          MI.getOperand(1).ChangeToRegister(0, false);
-        }
         DIExpr = DIExpression::prepend(DIExpr, PrependFlags, Offset);
         MI.getOperand(3).setMetadata(DIExpr);
         continue;
Index: llvm/test/CodeGen/ARM/dbg-range-extension.mir
===================================================================
--- llvm/test/CodeGen/ARM/dbg-range-extension.mir
+++ llvm/test/CodeGen/ARM/dbg-range-extension.mir
@@ -31,7 +31,7 @@
 # CHECK: DBG_VALUE [[REG_B]], $noreg, [[VAR_B]]
 # CHECK: DBG_VALUE [[REG_A]], $noreg, [[VAR_A]]
 # CHECK: DBG_VALUE [[REG_C:\$r[0-9]+]], $noreg, [[VAR_C]]
-# CHECK: DBG_VALUE 1, 0, [[VAR_I]]
+# CHECK: DBG_VALUE 1, $noreg, [[VAR_I]]
 
 # CHECK: bb.2.for.body
 # CHECK: DBG_VALUE [[REG_I:\$r[0-9]+]], $noreg, [[VAR_I]]
@@ -239,7 +239,7 @@
     $r6 = MOVr killed $r0, 14, $noreg, _, debug-location !26
     DBG_VALUE $r6, $noreg, !15, !20, debug-location !27
     $r7 = MOVi 1, 14, $noreg, $noreg
-    DBG_VALUE 1, 0, !18, !20, debug-location !28
+    DBG_VALUE 1, $noreg, !18, !20, debug-location !28
     B %bb.3.for.cond
   
   bb.2.for.body:
Index: llvm/test/CodeGen/MIR/X86/diexpr-win32.mir
===================================================================
--- llvm/test/CodeGen/MIR/X86/diexpr-win32.mir
+++ llvm/test/CodeGen/MIR/X86/diexpr-win32.mir
@@ -52,7 +52,7 @@
 # CHECK-NEXT:   BaseRegister:
 # CHECK-NEXT:   HasSpilledUDTMember: No
 # CHECK-NEXT:   OffsetInParent: 0
-# CHECK-NEXT:   BasePointerOffset: -4
+# CHECK-NEXT:   BasePointerOffset: 4
 # CHECK-NEXT:   LocalVariableAddrRange {
 # CHECK-NEXT:     OffsetStart:
 # CHECK-NEXT:     ISectStart:
@@ -193,8 +193,8 @@
     CFI_INSTRUCTION def_cfa_offset 8
     CFI_INSTRUCTION offset $esi, -8
     $esi = MOV32rm $esp, 1, _, 8, _ :: (load 4 from %fixed-stack.2)
-    DBG_VALUE $esp, 0, !26, !10, debug-location !25
-    DBG_VALUE $esp, 0, !23, !DIExpression(DW_OP_plus_uconst, 8, DW_OP_deref), debug-location !25
+    DBG_VALUE $esp, -2, !26, !10, debug-location !25
+    DBG_VALUE $esp, -3, !23, !DIExpression(DW_OP_deref), debug-location !25
     CALLpcrel32 @getString, csr_32, implicit $esp, implicit-def $esp, implicit-def $eax, debug-location !29
     $ecx = MOV32rm $eax, 1, _, 0, _, debug-location !29 :: (dereferenceable load 4 from %ir.1)
     $edx = MOV32rm $eax, 1, _, 4, _, debug-location !29 :: (dereferenceable load 4 from %ir.1 + 4)
@@ -245,7 +245,7 @@
   bb.0.entry:
     $eax = MOV32rm $esp, 1, _, 4, _ :: (load 4 from %fixed-stack.1)
     $eax = MOV32rm killed $eax, 1, _, 0, _, debug-location !34 :: (load 4 from %ir.0)
-    DBG_VALUE $eax, 0, !35, !DIExpression(DW_OP_constu, 4, DW_OP_minus), debug-location !34
+    DBG_VALUE $eax, -2, !35, !DIExpression(), debug-location !34
     $eax = ADD32rm killed $eax, $esp, 1, _, 8, _, implicit-def dead $eflags, debug-location !36 :: (load 4 from %fixed-stack.0)
     RET 0, $eax, debug-location !36
 
Index: llvm/test/CodeGen/X86/prologepilog_deref_size.mir
===================================================================
--- llvm/test/CodeGen/X86/prologepilog_deref_size.mir
+++ llvm/test/CodeGen/X86/prologepilog_deref_size.mir
@@ -1,4 +1,4 @@
-# RUN: llc -run-pass=prologepilog -o - %s | FileCheck %s
+# RUN: llc -start-before=prologepilog -stop-after=livedebugvalues -o - %s | FileCheck %s
 --- |
   ; ModuleID = 'dbg.opt.ll'
   source_filename = "dbg.c"
Index: llvm/test/DebugInfo/AArch64/compiler-gen-bbs-livedebugvalues.mir
===================================================================
--- llvm/test/DebugInfo/AArch64/compiler-gen-bbs-livedebugvalues.mir
+++ llvm/test/DebugInfo/AArch64/compiler-gen-bbs-livedebugvalues.mir
@@ -84,24 +84,24 @@
     renamable $w0 = ADDWri killed renamable $w0, 1, 0, debug-location !12
     DBG_VALUE renamable $w0, $noreg, !9, !DIExpression(), debug-location !12
     STRWui killed $w0, $sp, 3 :: (store 4 into %stack.0)
-    DBG_VALUE $sp, 0, !9, !DIExpression(DW_OP_plus_uconst, 12), debug-location !12
+    DBG_VALUE $sp, 0, !9, !DIExpression(), debug-location !12
 
     ; CHECK: DBG_VALUE renamable $w0, $noreg, !9, !DIExpression(), debug-location !12
     ; CHECK-NEXT: STRWui killed $w0, $sp, 3 :: (store 4 into %stack.0)
-    ; CHECK-NEXT: DBG_VALUE $sp, 0, !9, !DIExpression(DW_OP_plus_uconst, 12)
-    ; CHECK-NEXT: DBG_VALUE $sp, 0, !9, !DIExpression(DW_OP_plus_uconst, 12)
+    ; CHECK-NEXT: DBG_VALUE $sp, $noreg, !9, !DIExpression(DW_OP_plus_uconst, 12, DW_OP_deref)
+    ; CHECK-NEXT: DBG_VALUE $sp, $noreg, !9, !DIExpression(DW_OP_plus_uconst, 12, DW_OP_deref)
   
   bb.1.artificial-bb-1:
     ; CHECK-LABEL: bb.1.artificial-bb-1:
-    ; CHECK: DBG_VALUE $sp, 0, !9, !DIExpression(DW_OP_plus_uconst, 12)
+    ; CHECK: DBG_VALUE $sp, $noreg, !9, !DIExpression(DW_OP_plus_uconst, 12, DW_OP_deref)
       
   bb.2.artificial-bb-2:
     ; CHECK-LABEL: bb.2.artificial-bb-2:
-    ; CHECK: DBG_VALUE $sp, 0, !9, !DIExpression(DW_OP_plus_uconst, 12)
+    ; CHECK: DBG_VALUE $sp, $noreg, !9, !DIExpression(DW_OP_plus_uconst, 12, DW_OP_deref)
   
   bb.3.return:
     ; CHECK-LABEL: bb.3.return:
-    ; CHECK: DBG_VALUE $sp, 0, !9, !DIExpression(DW_OP_plus_uconst, 12)
+    ; CHECK: DBG_VALUE $sp, $noreg, !9, !DIExpression(DW_OP_plus_uconst, 12, DW_OP_deref)
 
     $w0 = LDRWui $sp, 3 :: (load 4 from %stack.0)
     BL @use, csr_aarch64_aapcs, implicit-def $lr, implicit $sp, implicit killed $w0
Index: llvm/test/DebugInfo/COFF/pieces.ll
===================================================================
--- llvm/test/DebugInfo/COFF/pieces.ll
+++ llvm/test/DebugInfo/COFF/pieces.ll
@@ -99,12 +99,14 @@
 ; ASM:         callq   g
 ; ASM:         movl    %eax, [[offset_o_x:[0-9]+]](%rsp)          # 4-byte Spill
 ; ASM: [[spill_o_x_start:\.Ltmp[0-9]+]]:
-; ASM:         #DEBUG_VALUE: bitpiece_spill:o <- [DW_OP_plus_uconst [[offset_o_x]], DW_OP_LLVM_fragment 32 32] [$rsp+0]
+; ASM:         #DEBUG_VALUE: bitpiece_spill:o <- [DW_OP_plus_uconst [[offset_o_x]], DW_OP_deref, DW_OP_LLVM_fragment 32 32] $rsp
 ; ASM:         #APP
 ; ASM:         #NO_APP
 ; ASM:         movl    [[offset_o_x]](%rsp), %eax          # 4-byte Reload
-; ASM:         retq
 ; ASM-NEXT: [[spill_o_x_end:\.Ltmp[0-9]+]]:
+; ASM-NEXT:    #DEBUG_VALUE: bitpiece_spill:o <- [DW_OP_LLVM_fragment 32 32] $eax
+; ASM:         retq
+; ASM-NEXT: .Ltmp
 ; ASM-NEXT: .Lfunc_end4:
 
 
@@ -231,7 +233,7 @@
 ; ASM:        .asciz  "bitpiece_spill"        # Function name
 ; ASM:        .short  4414                    # Record kind: S_LOCAL
 ; ASM:        .asciz  "o"
-; ASM:        .cv_def_range    [[spill_o_x_start]] .Lfunc_end4, reg_rel, 335, 65, 36
+; ASM:        .cv_def_range    [[spill_o_x_start]] [[spill_o_x_end]], reg_rel, 335, 65, 36
 
 ; OBJ-LABEL: GlobalProcIdSym {
 ; OBJ:         Kind: S_GPROC32_ID (0x1147)
Index: llvm/test/DebugInfo/MIR/X86/kill-after-spill.mir
===================================================================
--- llvm/test/DebugInfo/MIR/X86/kill-after-spill.mir
+++ llvm/test/DebugInfo/MIR/X86/kill-after-spill.mir
@@ -14,8 +14,8 @@
 # ...
 #
 # CHECK: bb.1.if.end:
-# CHECK: DBG_VALUE $rbp, 0, !37, !DIExpression(DW_OP_constu, 44, DW_OP_minus), debug-location !58
-# CHECK-NOT: DBG_VALUE $rbp, 0, !36, !DIExpression(DW_OP_constu, 48, DW_OP_minus), debug-location !57
+# CHECK: DBG_VALUE $rbp, $noreg, !37, !DIExpression(DW_OP_constu, 44, DW_OP_minus, DW_OP_deref), debug-location !58
+# CHECK-NOT: DBG_VALUE $rbp, $noreg, !36, !DIExpression(DW_OP_constu, 48, DW_OP_minus, DW_OP_deref), debug-location !57
 
 --- |
   ; ModuleID = '<stdin>'
Index: llvm/test/DebugInfo/MIR/X86/live-debug-values-3preds.mir
===================================================================
--- llvm/test/DebugInfo/MIR/X86/live-debug-values-3preds.mir
+++ llvm/test/DebugInfo/MIR/X86/live-debug-values-3preds.mir
@@ -190,7 +190,7 @@
     DBG_VALUE $esi, _, !10, !17, debug-location !19
     DBG_VALUE $edx, _, !11, !17, debug-location !21
     DBG_VALUE $ecx, _, !12, !17, debug-location !23
-    DBG_VALUE 0, 0, !13, !17, debug-location !25
+    DBG_VALUE 0, $noreg, !13, !17, debug-location !25
     $r8d = MOV32rr $esi, debug-location !26
     $r8d = IMUL32rr killed $r8d, $edi, implicit-def dead $eflags, debug-location !26
     TEST32rr $r8d, $r8d, implicit-def $eflags, debug-location !31
@@ -204,7 +204,7 @@
     DBG_VALUE $esi, _, !10, !17, debug-location !19
     DBG_VALUE $edx, _, !11, !17, debug-location !21
     DBG_VALUE $ecx, _, !12, !17, debug-location !23
-    DBG_VALUE 0, 0, !13, !17, debug-location !25
+    DBG_VALUE 0, $noreg, !13, !17, debug-location !25
     $eax = XOR32rr undef $eax, undef $eax, implicit-def dead $eflags
   
   bb.3.for.body (align 4):
@@ -215,7 +215,7 @@
     DBG_VALUE $esi, _, !10, !17, debug-location !19
     DBG_VALUE $edx, _, !11, !17, debug-location !21
     DBG_VALUE $ecx, _, !12, !17, debug-location !23
-    DBG_VALUE 0, 0, !13, !17, debug-location !25
+    DBG_VALUE 0, $noreg, !13, !17, debug-location !25
     TEST32rr $edi, $edi, implicit-def $eflags, debug-location !35
     JCC_1 %bb.4.if.then, 15, implicit $eflags
   
@@ -227,7 +227,7 @@
     DBG_VALUE $esi, _, !10, !17, debug-location !19
     DBG_VALUE $edx, _, !11, !17, debug-location !21
     DBG_VALUE $ecx, _, !12, !17, debug-location !23
-    DBG_VALUE 0, 0, !13, !17, debug-location !25
+    DBG_VALUE 0, $noreg, !13, !17, debug-location !25
     TEST32rr $esi, $esi, implicit-def $eflags, debug-location !39
     JCC_1 %bb.6.if.then.4, 15, implicit $eflags
   
@@ -239,7 +239,7 @@
     DBG_VALUE $esi, _, !10, !17, debug-location !19
     DBG_VALUE $edx, _, !11, !17, debug-location !21
     DBG_VALUE $ecx, _, !12, !17, debug-location !23
-    DBG_VALUE 0, 0, !13, !17, debug-location !25
+    DBG_VALUE 0, $noreg, !13, !17, debug-location !25
     TEST32rr $edx, $edx, implicit-def $eflags, debug-location !45
     JCC_1 %bb.8.if.then.8, 15, implicit $eflags
   
@@ -251,7 +251,7 @@
     DBG_VALUE $esi, _, !10, !17, debug-location !19
     DBG_VALUE $edx, _, !11, !17, debug-location !21
     DBG_VALUE $ecx, _, !12, !17, debug-location !23
-    DBG_VALUE 0, 0, !13, !17, debug-location !25
+    DBG_VALUE 0, $noreg, !13, !17, debug-location !25
     $eax = INC32r killed $eax, implicit-def dead $eflags, debug-location !44
     DBG_VALUE $eax, _, !13, !17, debug-location !25
     CMP32rr $eax, $r8d, implicit-def $eflags, debug-location !31
@@ -263,9 +263,9 @@
   
     DBG_VALUE $edi, _, !9, !17, debug-location !18
     DBG_VALUE $ecx, _, !12, !17, debug-location !23
-    DBG_VALUE 0, 0, !13, !17, debug-location !25
+    DBG_VALUE 0, $noreg, !13, !17, debug-location !25
     $ecx = IMUL32rr killed $ecx, killed $edi, implicit-def dead $eflags, debug-location !36
-    DBG_VALUE 0, 0, !13, !17, debug-location !25
+    DBG_VALUE 0, $noreg, !13, !17, debug-location !25
     $eax = MOV32rr killed $ecx, debug-location !50
     RETQ $eax, debug-location !50
   
@@ -274,9 +274,9 @@
   
     DBG_VALUE $esi, _, !10, !17, debug-location !19
     DBG_VALUE $ecx, _, !12, !17, debug-location !23
-    DBG_VALUE 0, 0, !13, !17, debug-location !25
+    DBG_VALUE 0, $noreg, !13, !17, debug-location !25
     $ecx = IMUL32rr killed $ecx, killed $esi, implicit-def dead $eflags, debug-location !40
-    DBG_VALUE 0, 0, !13, !17, debug-location !25
+    DBG_VALUE 0, $noreg, !13, !17, debug-location !25
     $eax = MOV32rr killed $ecx, debug-location !50
     RETQ $eax, debug-location !50
   
@@ -286,13 +286,13 @@
   
     DBG_VALUE $edx, _, !11, !17, debug-location !21
     DBG_VALUE $ecx, _, !12, !17, debug-location !23
-    DBG_VALUE 0, 0, !13, !17, debug-location !25
+    DBG_VALUE 0, $noreg, !13, !17, debug-location !25
     $ecx = IMUL32rr killed $ecx, killed $edx, implicit-def dead $eflags, debug-location !46
   
   bb.9.for.end:
     liveins: $ecx
   
-    DBG_VALUE 0, 0, !13, !17, debug-location !25
+    DBG_VALUE 0, $noreg, !13, !17, debug-location !25
     $eax = MOV32rr killed $ecx, debug-location !50
     RETQ $eax, debug-location !50
 
Index: llvm/test/DebugInfo/MIR/X86/live-debug-values-restore-collide.mir
===================================================================
--- llvm/test/DebugInfo/MIR/X86/live-debug-values-restore-collide.mir
+++ llvm/test/DebugInfo/MIR/X86/live-debug-values-restore-collide.mir
@@ -10,7 +10,7 @@
 # CHECK-LABEL: name: baaar
 # CHECK-LABEL: bb.0.entry:
 # CHECK:       DBG_VALUE $r9d, $noreg, !{{[0-9]*}}, !DIExpression()
-# CHECK:       DBG_VALUE $rsp, 0, !{{[0-9]*}}, !DIExpression(DW_OP_plus_uconst, 16)
+# CHECK:       DBG_VALUE $rsp, $noreg, !{{[0-9]*}}, !DIExpression(DW_OP_plus_uconst, 16, DW_OP_deref)
 # CHECK-NOT:   DBG_VALUE
 --- |
   target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
@@ -72,7 +72,7 @@
 
     ; Spill
     MOV32mr $rsp, 1, $noreg, 16, $noreg, $r9d :: (store 4 into %stack.0)
-    DBG_VALUE $rsp, 0, !9, !DIExpression(DW_OP_plus_uconst, 16), debug-location !10
+    DBG_VALUE $rsp, 0, !9, !DIExpression(), debug-location !10
 
     ; This load from the stack can be misinterpreted as a stack restore of
     ; any DBG_VALUe pointing at $rsp.
Index: llvm/test/DebugInfo/MIR/X86/live-debug-values-restore.mir
===================================================================
--- llvm/test/DebugInfo/MIR/X86/live-debug-values-restore.mir
+++ llvm/test/DebugInfo/MIR/X86/live-debug-values-restore.mir
@@ -29,7 +29,7 @@
 
 # Ascertain that the spill has been recognized and manifested in a DBG_VALUE.
 # CHECK: MOV64mr $rsp,{{.*-8.*}}killed{{.*}}$rdi :: (store 8 into %stack.0)
-# CHECK-NEXT: DBG_VALUE $rsp,{{.*}}![[PVAR]],{{.*}}!DIExpression(DW_OP_constu, 8, DW_OP_minus)
+# CHECK-NEXT: DBG_VALUE $rsp, $noreg, ![[PVAR]], !DIExpression(DW_OP_constu, 8, DW_OP_minus, DW_OP_deref)
 
 # Check for the restore.
 # CHECK: $rdi = MOV64rm $rsp,{{.*-8.*}}:: (load 8 from %stack.0)
@@ -408,15 +408,12 @@
 # This third function tests that complex expressions are spilt, and restored
 # correctly within a basic block.
 
-# FIXME: the spilt location below is wrong, there should be a deref between
-# the spill-offset and the DW_OP_plus_uconst.
-
 # CHECK-LABEL: name: h
 # CHECK-LABEL: bb.0.entry:
 # CHECK:       DBG_VALUE $rdi, $noreg, ![[RVAR]], !DIExpression(DW_OP_plus_uconst, 1)
 # CHECK-LABEL: bb.1.if.then:
 # CHECK:       DBG_VALUE $rdi, $noreg, ![[RVAR]], !DIExpression(DW_OP_plus_uconst, 1)
-# CHECK:       DBG_VALUE $rsp, 0, ![[RVAR]], !DIExpression(DW_OP_constu, 8, DW_OP_minus, DW_OP_plus_uconst, 1)
+# CHECK:       DBG_VALUE $rsp, $noreg, ![[RVAR]], !DIExpression(DW_OP_constu, 8, DW_OP_minus, DW_OP_deref, DW_OP_plus_uconst, 1)
 # CHECK:       DBG_VALUE $rdi, $noreg, ![[RVAR]], !DIExpression(DW_OP_plus_uconst, 1)
 # CHECK-LABEL: bb.2.if.end:
 # CHECK:       DBG_VALUE $rdi, $noreg, ![[RVAR]], !DIExpression(DW_OP_plus_uconst, 1)
@@ -518,8 +515,6 @@
 # bb 2 and 3, neither of which modifies the stack loc. The exit block (3)
 # should still be tracking the spill, and restore it on stack load.
 
-# FIXME: this test too contains a broken spill location.
-
 # Summary: loc is in $rdi in bb0, spills to stack in bb1, remains in stack
 # in bb2, starts in stack then loaded in bb3.
 
@@ -528,11 +523,11 @@
 # CHECK:       DBG_VALUE $rdi, $noreg, ![[SVAR]], !DIExpression(DW_OP_plus_uconst, 1)
 # CHECK-LABEL: bb.1.foo:
 # CHECK:       DBG_VALUE $rdi, $noreg, ![[SVAR]], !DIExpression(DW_OP_plus_uconst, 1)
-# CHECK:       DBG_VALUE $rsp, 0, ![[SVAR]], !DIExpression(DW_OP_constu, 8, DW_OP_minus, DW_OP_plus_uconst, 1)
+# CHECK:       DBG_VALUE $rsp, $noreg, ![[SVAR]], !DIExpression(DW_OP_constu, 8, DW_OP_minus, DW_OP_deref, DW_OP_plus_uconst, 1)
 # CHECK-LABEL: bb.2.if.then:
-# CHECK:       DBG_VALUE $rsp, 0, ![[SVAR]], !DIExpression(DW_OP_constu, 8, DW_OP_minus, DW_OP_plus_uconst, 1)
+# CHECK:       DBG_VALUE $rsp, $noreg, ![[SVAR]], !DIExpression(DW_OP_constu, 8, DW_OP_minus, DW_OP_deref, DW_OP_plus_uconst, 1)
 # CHECK-LABEL: bb.3.if.end
-# CHECK:       DBG_VALUE $rsp, 0, ![[SVAR]], !DIExpression(DW_OP_constu, 8, DW_OP_minus, DW_OP_plus_uconst, 1)
+# CHECK:       DBG_VALUE $rsp, $noreg, ![[SVAR]], !DIExpression(DW_OP_constu, 8, DW_OP_minus, DW_OP_deref, DW_OP_plus_uconst, 1)
 # CHECK:       DBG_VALUE $rdi, $noreg, ![[SVAR]], !DIExpression(DW_OP_plus_uconst, 1)
 name:            i
 alignment:       16
@@ -633,17 +628,15 @@
 ...
 ---
 # Test that if an unspilt DBG_VALUE starts as an indirect DBG_VALUE, then it
-# is restored as an indirect DBG_VALUE. FIXME: Note that for the intervening
-# period of being a spilt location there is still a missing layer of
-# indirection.
+# is restored as an indirect DBG_VALUE.
 
 # CHECK-LABEL: name: j
 # CHECK-LABEL: bb.0.entry:
-# CHECK:       DBG_VALUE $rdi, 0, ![[TVAR]], !DIExpression()
+# CHECK:       DBG_VALUE $rdi, $noreg, ![[TVAR]], !DIExpression(DW_OP_deref)
 # CHECK-LABEL: bb.1.if.then:
-# CHECK:       DBG_VALUE $rsp, 0, ![[TVAR]], !DIExpression(DW_OP_constu, 8, DW_OP_minus)
+# CHECK:       DBG_VALUE $rsp, $noreg, ![[TVAR]], !DIExpression(DW_OP_constu, 8, DW_OP_minus, DW_OP_deref, DW_OP_deref)
 # CHECK:       INLINEASM
-# CHECK:       DBG_VALUE ${{[a-zA-Z0-9]+}}, 0, ![[TVAR]], !DIExpression()
+# CHECK:       DBG_VALUE ${{[a-zA-Z0-9]+}}, $noreg, ![[TVAR]], !DIExpression(DW_OP_deref)
 # CHECK-LABEL: bb.2.if.end
 
 name:            j
@@ -684,8 +677,8 @@
     successors: %bb.2, %bb.1
     liveins: $rdi, $rbx, $r12, $r13, $r14, $r15, $rbp
   
-    DBG_VALUE $rdi, 0, !404, !DIExpression(), debug-location !405
-    DBG_VALUE $rdi, 0, !404, !DIExpression(), debug-location !405
+    DBG_VALUE $rdi, $noreg, !404, !DIExpression(DW_OP_deref), debug-location !405
+    DBG_VALUE $rdi, $noreg, !404, !DIExpression(DW_OP_deref), debug-location !405
     TEST64rr renamable $rdi, renamable $rdi, implicit-def $eflags, debug-location !406
     JCC_1 %bb.2, 4, implicit $eflags, debug-location !408
   
Index: llvm/test/DebugInfo/MIR/X86/live-debug-values-spill.mir
===================================================================
--- llvm/test/DebugInfo/MIR/X86/live-debug-values-spill.mir
+++ llvm/test/DebugInfo/MIR/X86/live-debug-values-spill.mir
@@ -53,29 +53,29 @@
 #
 # GENERATE:      bb.1.if.end:
 # GENERATE:      MOV32mr $rbp, 1, $noreg, -48, $noreg, killed $edx :: (store 4 into %stack.5)
-# GENERATE-NEXT: DBG_VALUE $rbp, 0, ![[INT0]], !DIExpression(DW_OP_constu, 48, DW_OP_minus)
+# GENERATE-NEXT: DBG_VALUE $rbp, $noreg, ![[INT0]], !DIExpression(DW_OP_constu, 48, DW_OP_minus, DW_OP_deref)
 # GENERATE:      MOV32mr $rbp, 1, $noreg, -52, $noreg, killed $r8d :: (store 4 into %stack.4)
-# GENERATE-NEXT: DBG_VALUE $rbp, 0, ![[INTB]], !DIExpression(DW_OP_constu, 52, DW_OP_minus)
+# GENERATE-NEXT: DBG_VALUE $rbp, $noreg, ![[INTB]], !DIExpression(DW_OP_constu, 52, DW_OP_minus, DW_OP_deref)
 # GENERATE:      MOV32mr $rbp, 1, $noreg, -56, $noreg, killed $esi :: (store 4 into %stack.3)
-# GENERATE-NEXT: DBG_VALUE $rbp, 0, ![[INTD]], !DIExpression(DW_OP_constu, 56, DW_OP_minus)
+# GENERATE-NEXT: DBG_VALUE $rbp, $noreg, ![[INTD]], !DIExpression(DW_OP_constu, 56, DW_OP_minus, DW_OP_deref)
 #
 # Check that the spill locations that are valid at the end of bb.1.if.end are
 # propagated to subsequent BBs.
 #
 # GENERATE:      bb.2.if.then4:
 # GENERATE-NOT:  bb.3:
-# GENERATE-DAG:  DBG_VALUE $rbp, 0, ![[INTD]], !DIExpression(DW_OP_constu, 56, DW_OP_minus)
-# GENERATE-DAG:  DBG_VALUE $rbp, 0, ![[INTB]], !DIExpression(DW_OP_constu, 52, DW_OP_minus)
+# GENERATE-DAG:  DBG_VALUE $rbp, $noreg, ![[INTD]], !DIExpression(DW_OP_constu, 56, DW_OP_minus, DW_OP_deref)
+# GENERATE-DAG:  DBG_VALUE $rbp, $noreg, ![[INTB]], !DIExpression(DW_OP_constu, 52, DW_OP_minus, DW_OP_deref)
 #
 # GENERATE:      bb.3:
 # GENERATE-NOT:  bb.4.if.end13:
-# GENERATE-DAG:  DBG_VALUE $rbp, 0, ![[INTD]], !DIExpression(DW_OP_constu, 56, DW_OP_minus)
-# GENERATE-DAG:  DBG_VALUE $rbp, 0, ![[INTB]], !DIExpression(DW_OP_constu, 52, DW_OP_minus)
+# GENERATE-DAG:  DBG_VALUE $rbp, $noreg, ![[INTD]], !DIExpression(DW_OP_constu, 56, DW_OP_minus, DW_OP_deref)
+# GENERATE-DAG:  DBG_VALUE $rbp, $noreg, ![[INTB]], !DIExpression(DW_OP_constu, 52, DW_OP_minus, DW_OP_deref)
 #
 # GENERATE:      bb.4.if.end13:
 # GENERATE-NOT:  bb.5.cleanup:
-# GENERATE-DAG:  DBG_VALUE $rbp, 0, ![[INTD]], !DIExpression(DW_OP_constu, 56, DW_OP_minus)
-# GENERATE-DAG:  DBG_VALUE $rbp, 0, ![[INTB]], !DIExpression(DW_OP_constu, 52, DW_OP_minus)
+# GENERATE-DAG:  DBG_VALUE $rbp, $noreg, ![[INTD]], !DIExpression(DW_OP_constu, 56, DW_OP_minus, DW_OP_deref)
+# GENERATE-DAG:  DBG_VALUE $rbp, $noreg, ![[INTB]], !DIExpression(DW_OP_constu, 52, DW_OP_minus, DW_OP_deref)
 # 
 # Check that the spill location rbp-48 (the variable int0) is not propagated 
 # because int0 is redefined within the same basic block.
@@ -369,31 +369,31 @@
     CFI_INSTRUCTION offset $r13, -40
     CFI_INSTRUCTION offset $r14, -32
     CFI_INSTRUCTION offset $r15, -24
-    DBG_VALUE $edi, _, !24, !38, debug-location !39
-    DBG_VALUE $esi, _, !25, !38, debug-location !40
-    DBG_VALUE $edx, _, !26, !38, debug-location !41
-    DBG_VALUE $ecx, _, !27, !38, debug-location !42
-    DBG_VALUE $r8d, _, !28, !38, debug-location !43
-    DBG_VALUE $r9d, _, !29, !38, debug-location !44
+    DBG_VALUE $edi, $noreg, !24, !38, debug-location !39
+    DBG_VALUE $esi, $noreg, !25, !38, debug-location !40
+    DBG_VALUE $edx, $noreg, !26, !38, debug-location !41
+    DBG_VALUE $ecx, $noreg, !27, !38, debug-location !42
+    DBG_VALUE $r8d, $noreg, !28, !38, debug-location !43
+    DBG_VALUE $r9d, $noreg, !29, !38, debug-location !44
     $r14d = MOV32rr $r8d
-    DBG_VALUE $r14d, _, !28, !38, debug-location !43
+    DBG_VALUE $r14d, $noreg, !28, !38, debug-location !43
     $r12d = MOV32rr $esi
     DBG_VALUE $r12d, _, !25, !38, debug-location !40
     $eax = MOV32rr $edi
-    DBG_VALUE $eax, _, !24, !38, debug-location !39
+    DBG_VALUE $eax, $noreg, !24, !38, debug-location !39
     $r13d = MOV32rm $rip, 1, _, @glob0, _, debug-location !46 :: (dereferenceable load 4 from @glob0, !tbaa !47)
-    DBG_VALUE $r13d, _, !31, !38, debug-location !51
+    DBG_VALUE $r13d, $noreg, !31, !38, debug-location !51
     $r8d = MOV32rm $rip, 1, _, @glob1, _, debug-location !52 :: (dereferenceable load 4 from @glob1, !tbaa !47)
-    DBG_VALUE $r8d, _, !32, !38, debug-location !53
+    DBG_VALUE $r8d, $noreg, !32, !38, debug-location !53
     $r15d = MOV32rm $rip, 1, _, @glob2, _, debug-location !54 :: (dereferenceable load 4 from @glob2, !tbaa !47)
-    DBG_VALUE $r15d, _, !33, !38, debug-location !55
+    DBG_VALUE $r15d, $noreg, !33, !38, debug-location !55
     $esi = MOV32rm $rip, 1, _, @glob3, _, debug-location !56 :: (dereferenceable load 4 from @glob3, !tbaa !47)
-    DBG_VALUE $esi, _, !34, !38, debug-location !57
+    DBG_VALUE $esi, $noreg, !34, !38, debug-location !57
     $ebx = MOV32rm $rip, 1, _, @glob4, _, debug-location !59 :: (dereferenceable load 4 from @glob4, !tbaa !47)
-    DBG_VALUE $ebx, _, !35, !38, debug-location !60
+    DBG_VALUE $ebx, $noreg, !35, !38, debug-location !60
     MOV32mr $rbp, 1, _, -44, _, $ebx, debug-location !60 :: (store 4 into %ir.inte, !tbaa !47)
     $edi = MOV32rm $rip, 1, _, @glob5, _, debug-location !62 :: (dereferenceable load 4 from @glob5, !tbaa !47)
-    DBG_VALUE $edi, _, !36, !38, debug-location !63
+    DBG_VALUE $edi, $noreg, !36, !38, debug-location !63
     MOV32mr $rbp, 1, _, -60, _, $edi, debug-location !63 :: (store 4 into %ir.intf, !tbaa !47)
     TEST32rr killed $eax, $eax, implicit-def $eflags, debug-location !67
     JCC_1 %bb.5.cleanup, 5, implicit $eflags
@@ -405,11 +405,11 @@
     MOV32mr $rbp, 1, _, -48, _, killed $edx :: (store 4 into %stack.5)
     MOV32mr $rbp, 1, _, -52, _, killed $r8d :: (store 4 into %stack.4)
     MOV32mr $rbp, 1, _, -56, _, killed $esi :: (store 4 into %stack.3)
-    DBG_VALUE _, _, !30, !38, debug-location !45
+    DBG_VALUE $noreg, $noreg, !30, !38, debug-location !45
     $r14d = ADD32rr killed $r14d, killed $ecx, implicit-def dead $eflags, debug-location !68
     $r14d = ADD32rr killed $r14d, killed $r9d, implicit-def dead $eflags, debug-location !69
     $r14d = IMUL32rm killed $r14d, $rbp, 1, _, 16, _, implicit-def dead $eflags, debug-location !70 :: (load 4 from %fixed-stack.6, align 16)
-    DBG_VALUE $r14d, _, !26, !38, debug-location !41
+    DBG_VALUE $r14d, $noreg, !26, !38, debug-location !41
     CALL64pcrel32 @use, csr_64, implicit $rsp, implicit $edi, implicit-def $rsp, debug-location !72
     $edi = MOV32rr killed $ebx, debug-location !73
     CALL64pcrel32 @use, csr_64, implicit $rsp, implicit $edi, implicit-def $rsp, debug-location !73
@@ -421,21 +421,21 @@
     liveins: $r14d, $r15d, $rbp
   
     $rdi = LEA64r $rbp, 1, _, -44, _
-    DBG_VALUE $rbp, -44, !35, !38, debug-location !60
+    DBG_VALUE $rbp, 0, !35, !38, debug-location !60
     $rsi = LEA64r $rbp, 1, _, -60, _
-    DBG_VALUE $rbp, -60, !36, !38, debug-location !63
+    DBG_VALUE $rbp, 1, !36, !38, debug-location !63
     $rdx = LEA64r $rbp, 1, _, -64, _
-    DBG_VALUE $rbp, -64, !37, !38, debug-location !78
+    DBG_VALUE $rbp, 2, !37, !38, debug-location !78
     CALL64pcrel32 @set, csr_64, implicit $rsp, implicit $rdi, implicit $rsi, implicit $rdx, implicit-def $rsp, debug-location !79
     $eax = MOV32rm $rbp, 1, _, -44, _, debug-location !81 :: (dereferenceable load 4 from %ir.inte, !tbaa !47)
-    DBG_VALUE $eax, _, !35, !38, debug-location !60
+    DBG_VALUE $eax, $noreg, !35, !38, debug-location !60
     $r15d = ADD32rm killed $r15d, $rbp, 1, _, -52, _, implicit-def dead $eflags, debug-location !82 :: (load 4 from %stack.4)
     $r15d = IMUL32rr killed $r15d, $eax, implicit-def dead $eflags, debug-location !82
     $r15d = ADD32rm killed $r15d, $rbp, 1, _, -56, _, implicit-def dead $eflags, debug-location !83 :: (load 4 from %stack.3)
     $r15d = IMUL32rr killed $r15d, killed $eax, implicit-def dead $eflags, debug-location !84
-    DBG_VALUE $r15d, _, !31, !38, debug-location !51
+    DBG_VALUE $r15d, $noreg, !31, !38, debug-location !51
     $r13d = MOV32rr killed $r15d
-    DBG_VALUE $r13d, _, !31, !38, debug-location !51
+    DBG_VALUE $r13d, $noreg, !31, !38, debug-location !51
     JMP_1 %bb.4.if.end13
   
   bb.2:
@@ -443,17 +443,17 @@
     liveins: $r13d, $r14d, $rbp
   
     $r14d = ADD32rm killed $r14d, $rbp, 1, _, -48, _, implicit-def dead $eflags, debug-location !71 :: (load 4 from %stack.5)
-    DBG_VALUE $r14d, _, !26, !38, debug-location !41
+    DBG_VALUE $r14d, $noreg, !26, !38, debug-location !41
   
   bb.4.if.end13:
     successors: %bb.5.cleanup(0x80000000)
     liveins: $r13d, $r14d, $rbp
   
-    DBG_VALUE $r14d, _, !26, !38, debug-location !41
-    DBG_VALUE $r13d, _, !31, !38, debug-location !51
+    DBG_VALUE $r14d, $noreg, !26, !38, debug-location !41
+    DBG_VALUE $r13d, $noreg, !31, !38, debug-location !51
     $r13d = IMUL32rm killed $r13d, $rbp, 1, _, 16, _, implicit-def dead $eflags, debug-location !86 :: (load 4 from %fixed-stack.6, align 16)
     $r13d = ADD32rr killed $r13d, killed $r14d, implicit-def dead $eflags, debug-location !87
-    DBG_VALUE $r13d, _, !26, !38, debug-location !41
+    DBG_VALUE $r13d, $noreg, !26, !38, debug-location !41
     $edi = MOV32rr killed $r13d, debug-location !88
     CALL64pcrel32 @use, csr_64, implicit $rsp, implicit $edi, implicit-def $rsp, debug-location !88
   
Index: llvm/test/DebugInfo/MIR/X86/live-debug-values-stack-clobber.mir
===================================================================
--- llvm/test/DebugInfo/MIR/X86/live-debug-values-stack-clobber.mir
+++ llvm/test/DebugInfo/MIR/X86/live-debug-values-stack-clobber.mir
@@ -36,9 +36,11 @@
 # These variables should be spilt,
 # CHECK-LABEL: bb.1.if.end:
 # CHECK:       MOV64mr $rsp, 1, $noreg, 16, $noreg, killed renamable $rsi
-# CHECK-NEXT:  DBG_VALUE $rsp, 0, ![[BNUM]], !DIExpression(
+# CHECK-NEXT:  DBG_VALUE $rsp, $noreg, ![[BNUM]], !DIExpression(
+# CHECK-SAME:         DW_OP_plus_uconst, 16, DW_OP_deref)
 # CHECK-NEXT:  MOV64mr $rsp, 1, $noreg, 8, $noreg, killed renamable $rdi
-# CHECK-NEXT:  DBG_VALUE $rsp, 0, ![[ANUM]], !DIExpression(
+# CHECK-NEXT:  DBG_VALUE $rsp, $noreg, ![[ANUM]], !DIExpression(
+# CHECK-SAME:         DW_OP_plus_uconst, 8, DW_OP_deref)
 # CHECK-NEXT:  INLINEASM
 #
 # Then the location of "a" should be terminated when overwritten
Index: llvm/test/DebugInfo/MIR/X86/prolog-epilog-indirection.mir
===================================================================
--- llvm/test/DebugInfo/MIR/X86/prolog-epilog-indirection.mir
+++ llvm/test/DebugInfo/MIR/X86/prolog-epilog-indirection.mir
@@ -19,7 +19,7 @@
 # CHECK-NEXT: DBG_VALUE $rsp, $noreg, ![[VAR3]], !DIExpression(DW_OP_plus_uconst, {{[0-9]+}}, DW_OP_LLVM_tag_offset, 0, DW_OP_stack_value)
 # CHECK-NEXT: DBG_VALUE 1834104526
 # CHECK-NEXT: MOV64mr
-# CHECK-NEXT: DBG_VALUE $rsp, 0, ![[VAR]], !DIExpression(DW_OP_plus_uconst, {{[0-9]+}})
+# CHECK-NEXT: DBG_VALUE $rsp, 0, ![[VAR]], !DIExpression()
 
 --- |
   ; ModuleID = 'out.ll'
Index: llvm/test/DebugInfo/PowerPC/live-debug-vars-subreg-offset.ll
===================================================================
--- llvm/test/DebugInfo/PowerPC/live-debug-vars-subreg-offset.ll
+++ llvm/test/DebugInfo/PowerPC/live-debug-vars-subreg-offset.ll
@@ -33,7 +33,7 @@
 ; CHECK: ![[VAR:.*]] = !DILocalVariable(name: "spilled"
 
 ; CHECK: STD $x3, 0, %stack.0
-; CHECK-NEXT: DBG_VALUE %stack.0, 0, ![[VAR]], !DIExpression(DW_OP_plus_uconst, 4)
+; CHECK-NEXT: DBG_VALUE %stack.0, 0, ![[VAR]], !DIExpression()
 
 ; Function Attrs: noreturn nounwind
 define signext i32 @main() local_unnamed_addr #0 !dbg !8 {
Index: llvm/test/DebugInfo/X86/dbg-declare-arg.ll
===================================================================
--- llvm/test/DebugInfo/X86/dbg-declare-arg.ll
+++ llvm/test/DebugInfo/X86/dbg-declare-arg.ll
@@ -17,10 +17,14 @@
 ;   return my_a;
 ; }
 
+; dbg.declare for agg.result becomes a single DBG_VALUE, appearing first in a
+; spill slot, which is later restored into rcx.
+
 ; CHECK: DW_AT_name {{.*}}"j"
 ; CHECK: DW_TAG_variable
 ; CHECK-NEXT:   DW_AT_location [DW_FORM_sec_offset] (
-; CHECK-NEXT:     [0x{{.*}}, 0x{{.*}}): DW_OP_breg7 RSP+16, DW_OP_deref)
+; CHECK-NEXT:     [0x{{.*}}, 0x{{.*}}): DW_OP_breg7 RSP+16, DW_OP_deref
+; CHECK-NEXT:     [0x{{.*}}, 0x{{.*}}): DW_OP_breg2 RCX+0)
 ; CHECK-NEXT:   DW_AT_name {{.*}}"my_a"
 
 %class.A = type { i32, i32, i32, i32 }
Index: llvm/test/DebugInfo/X86/dbg-value-of-spill-with-fp.ll
===================================================================
--- /dev/null
+++ llvm/test/DebugInfo/X86/dbg-value-of-spill-with-fp.ll
@@ -0,0 +1,83 @@
+; RUN: llc -start-after=codegenprepare %s -mtriple=i386-unknown-unknown -filetype=obj -o - | llvm-dwarfdump - --name=result | FileCheck %s
+
+; Like dbg-value-when-spilt.ll, but testing what happens when we have a stack
+; spill location and the stack pointer is modified. LiveDebugValues could
+; interpret the spilt-location as being invalidated by $esp being def'd, for
+; example by pushing a value onto the stack during a call (@extern below).
+; It shouldn't -- the debugger should be aware of the call site and take
+; account of it.
+
+; FIXME: While LiveDebugValues handles this correctly,
+; DbgEntityHistoryCalculator still terminates the location of 'result' early,
+; hence there's a gap (and repeated location spec) in the DWARF produced.
+
+; CHECK:      DW_TAG_variable
+; CHECK-NEXT: DW_AT_location
+; CHECK-NEXT: DW_OP_breg4 ESP+[[SLOT:[0-9]]]
+; CHECK-NEXT: DW_OP_breg4 ESP+[[SLOT]]
+; CHECK-NEXT: DW_OP_reg0 EAX)
+
+target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
+
+@someglobal = global i32 0
+
+define i32 @_Z10get_stringv() !dbg !7 {
+entry:
+  %somearg = load i32, i32 *@someglobal
+  %nrvo = alloca i1, align 1
+  store i1 false, i1* %nrvo, align 1, !dbg !24
+  call void asm sideeffect "", "~{eax},~{ebx},~{ecx},~{edx},~{esi},~{edi},~{ebp},~{dirflag},~{fpsr},~{flags}"(), !dbg !24, !srcloc !28
+  call void @llvm.dbg.value(metadata i32 %somearg, metadata !23, metadata !DIExpression()), !dbg !24
+  call void @extern(i32 0), !dbg !24
+  call void asm sideeffect "", "~{eax},~{ebx},~{ecx},~{edx},~{esi},~{edi},~{ebp},~{dirflag},~{fpsr},~{flags}"(), !dbg !24, !srcloc !28
+  store i1 true, i1* %nrvo, align 1, !dbg !24
+  %nrvo.val = load i1, i1* %nrvo, align 1, !dbg !24
+  br i1 %nrvo.val, label %blocka, label %blockb, !dbg !24
+
+blocka:
+  store i32 0, i32 *@someglobal
+  br label %exit, !dbg !24
+
+blockb:
+  store i32 1, i32 *@someglobal
+  br label %exit, !dbg !24
+
+exit:
+  ret i32 %somearg, !dbg !24
+}
+
+; Function Attrs: nounwind readnone speculatable
+declare void @llvm.dbg.value(metadata, metadata, metadata)
+
+declare void @extern(i32)
+
+!llvm.dbg.cu = !{!0}
+!llvm.module.flags = !{!3, !4, !5}
+!llvm.ident = !{!6}
+
+!0 = distinct !DICompileUnit(language: DW_LANG_C_plus_plus, file: !1, producer: "clang version 6.0.0 ", isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug, enums: !2)
+!1 = !DIFile(filename: "t.cpp", directory: "C:\5Csrc\5Cllvm-project\5Cbuild")
+!2 = !{}
+!3 = !{i32 2, !"Dwarf Version", i32 4}
+!4 = !{i32 2, !"Debug Info Version", i32 3}
+!5 = !{i32 1, !"wchar_size", i32 4}
+!6 = !{!"clang version 6.0.0 "}
+!7 = distinct !DISubprogram(name: "get_string", linkageName: "_Z10get_stringv", scope: !1, file: !1, line: 13, type: !8, isLocal: false, isDefinition: true, scopeLine: 13, flags: DIFlagPrototyped, isOptimized: true, unit: !0, retainedNodes: !22)
+!8 = !DISubroutineType(types: !9)
+!9 = !{!10}
+!10 = distinct !DICompositeType(tag: DW_TAG_structure_type, name: "string", file: !1, line: 7, size: 32, elements: !11, identifier: "_ZTS6string")
+!11 = !{!12, !14, !18, !21}
+!12 = !DIDerivedType(tag: DW_TAG_member, name: "i", scope: !10, file: !1, line: 11, baseType: !13, size: 32)
+!13 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed)
+!14 = !DISubprogram(name: "string", scope: !10, file: !1, line: 8, type: !15, isLocal: false, isDefinition: false, scopeLine: 8, flags: DIFlagPrototyped, isOptimized: true)
+!15 = !DISubroutineType(types: !16)
+!16 = !{null, !17}
+!17 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: !10, size: 64, flags: DIFlagArtificial | DIFlagObjectPointer)
+!18 = !DISubprogram(name: "string", scope: !10, file: !1, line: 9, type: !19, isLocal: false, isDefinition: false, scopeLine: 9, flags: DIFlagPrototyped, isOptimized: true)
+!19 = !DISubroutineType(types: !20)
+!20 = !{null, !17, !13}
+!21 = !DISubprogram(name: "~string", scope: !10, file: !1, line: 10, type: !15, isLocal: false, isDefinition: false, scopeLine: 10, flags: DIFlagPrototyped, isOptimized: true)
+!22 = !{!23}
+!23 = !DILocalVariable(name: "result", scope: !7, file: !1, line: 14, type: !10)
+!24 = !DILocation(line: 14, column: 3, scope: !7)
+!28 = !{i32 -2147471175}
Index: llvm/test/DebugInfo/X86/dbg-value-when-spilt.ll
===================================================================
--- /dev/null
+++ llvm/test/DebugInfo/X86/dbg-value-when-spilt.ll
@@ -0,0 +1,79 @@
+; RUN: llc -start-after=codegenprepare %s -mtriple=x86_64-unknown-unknown -filetype=obj -o - | llvm-dwarfdump - --name=result | FileCheck %s
+
+; This is a copy of spill-indirect-nrvo.ll, testing that if we have a
+; dbg.value of a Value at a point where it's in a spill slot, then we should
+; be able to track through subsequent loads, regardless of implementation.
+
+; FIXME: Originally there was a conditional a call before return
+; (see spill-indirect-nrvo.ll); the spilt value was loaded into $rbx before
+; the call, but LiveDebugValues missed the later copy to $rax for return.
+
+; CHECK:      DW_TAG_variable
+; CHECK-NEXT: DW_AT_location
+; CHECK-NEXT: DW_OP_breg7 RSP+{{[0-9]}}
+; CHECK-NEXT: DW_OP_reg0 RAX)
+
+target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
+target triple = "x86_64--linux"
+
+@someglobal = global i32 0
+
+define i32 @_Z10get_stringv(i32 %somearg) !dbg !7 {
+entry:
+  %nrvo = alloca i1, align 1
+  store i1 false, i1* %nrvo, align 1, !dbg !24
+  call void @extern(i32 %somearg), !dbg !24
+  call void asm sideeffect "", "~{rax},~{rbx},~{rcx},~{rdx},~{rsi},~{rdi},~{rbp},~{r8},~{r9},~{r10},~{r11},~{r12},~{r13},~{r14},~{r15},~{dirflag},~{fpsr},~{flags}"(), !dbg !24, !srcloc !28
+  call void @llvm.dbg.value(metadata i32 %somearg, metadata !23, metadata !DIExpression()), !dbg !24
+  call void asm sideeffect "", "~{rax},~{rbx},~{rcx},~{rdx},~{rsi},~{rdi},~{rbp},~{r8},~{r9},~{r10},~{r11},~{r12},~{r13},~{r14},~{r15},~{dirflag},~{fpsr},~{flags}"(), !dbg !24, !srcloc !28
+  store i1 true, i1* %nrvo, align 1, !dbg !24
+  %nrvo.val = load i1, i1* %nrvo, align 1, !dbg !24
+  br i1 %nrvo.val, label %blocka, label %blockb, !dbg !24
+
+blocka:
+  store i32 0, i32 *@someglobal
+  br label %exit, !dbg !24
+
+blockb:
+  store i32 1, i32 *@someglobal
+  br label %exit, !dbg !24
+
+exit:
+  ret i32 %somearg, !dbg !24
+}
+
+; Function Attrs: nounwind readnone speculatable
+declare void @llvm.dbg.value(metadata, metadata, metadata)
+
+declare void @extern(i32)
+
+!llvm.dbg.cu = !{!0}
+!llvm.module.flags = !{!3, !4, !5}
+!llvm.ident = !{!6}
+
+!0 = distinct !DICompileUnit(language: DW_LANG_C_plus_plus, file: !1, producer: "clang version 6.0.0 ", isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug, enums: !2)
+!1 = !DIFile(filename: "t.cpp", directory: "C:\5Csrc\5Cllvm-project\5Cbuild")
+!2 = !{}
+!3 = !{i32 2, !"Dwarf Version", i32 4}
+!4 = !{i32 2, !"Debug Info Version", i32 3}
+!5 = !{i32 1, !"wchar_size", i32 4}
+!6 = !{!"clang version 6.0.0 "}
+!7 = distinct !DISubprogram(name: "get_string", linkageName: "_Z10get_stringv", scope: !1, file: !1, line: 13, type: !8, isLocal: false, isDefinition: true, scopeLine: 13, flags: DIFlagPrototyped, isOptimized: true, unit: !0, retainedNodes: !22)
+!8 = !DISubroutineType(types: !9)
+!9 = !{!10}
+!10 = distinct !DICompositeType(tag: DW_TAG_structure_type, name: "string", file: !1, line: 7, size: 32, elements: !11, identifier: "_ZTS6string")
+!11 = !{!12, !14, !18, !21}
+!12 = !DIDerivedType(tag: DW_TAG_member, name: "i", scope: !10, file: !1, line: 11, baseType: !13, size: 32)
+!13 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed)
+!14 = !DISubprogram(name: "string", scope: !10, file: !1, line: 8, type: !15, isLocal: false, isDefinition: false, scopeLine: 8, flags: DIFlagPrototyped, isOptimized: true)
+!15 = !DISubroutineType(types: !16)
+!16 = !{null, !17}
+!17 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: !10, size: 64, flags: DIFlagArtificial | DIFlagObjectPointer)
+!18 = !DISubprogram(name: "string", scope: !10, file: !1, line: 9, type: !19, isLocal: false, isDefinition: false, scopeLine: 9, flags: DIFlagPrototyped, isOptimized: true)
+!19 = !DISubroutineType(types: !20)
+!20 = !{null, !17, !13}
+!21 = !DISubprogram(name: "~string", scope: !10, file: !1, line: 10, type: !15, isLocal: false, isDefinition: false, scopeLine: 10, flags: DIFlagPrototyped, isOptimized: true)
+!22 = !{!23}
+!23 = !DILocalVariable(name: "result", scope: !7, file: !1, line: 14, type: !10)
+!24 = !DILocation(line: 14, column: 3, scope: !7)
+!28 = !{i32 -2147471175}
Index: llvm/test/DebugInfo/X86/fission-ranges.ll
===================================================================
--- llvm/test/DebugInfo/X86/fission-ranges.ll
+++ llvm/test/DebugInfo/X86/fission-ranges.ll
@@ -10,11 +10,11 @@
 ; LiveDebugValues should produce DBG_VALUEs for variable "b" in successive
 ; blocks once we recognize that it is spilled.
 ; CHECK-MIR: ![[BDIVAR:[0-9]+]] = !DILocalVariable(name: "b"
-; CHECK-MIR: DBG_VALUE $rsp, 0, ![[BDIVAR]], !DIExpression(DW_OP_constu, 32, DW_OP_minus)
+; CHECK-MIR: DBG_VALUE $rsp, $noreg, ![[BDIVAR]], !DIExpression(DW_OP_constu, 32, DW_OP_minus, DW_OP_deref)
 ; CHECK-MIR-LABEL: bb.6.for.inc13:
-; CHECK-MIR: DBG_VALUE $rsp, 0, ![[BDIVAR]], !DIExpression(DW_OP_constu, 32, DW_OP_minus)
+; CHECK-MIR: DBG_VALUE $rsp, $noreg, ![[BDIVAR]], !DIExpression(DW_OP_constu, 32, DW_OP_minus, DW_OP_deref)
 ; CHECK-MIR-LABEL: bb.7.for.inc16:
-; CHECK-MIR: DBG_VALUE $rsp, 0, ![[BDIVAR]], !DIExpression(DW_OP_constu, 32, DW_OP_minus)
+; CHECK-MIR: DBG_VALUE $rsp, $noreg, ![[BDIVAR]], !DIExpression(DW_OP_constu, 32, DW_OP_minus, DW_OP_deref)
 
 
 ; CHECK: .debug_info contents:
Index: llvm/test/DebugInfo/X86/op_deref.ll
===================================================================
--- llvm/test/DebugInfo/X86/op_deref.ll
+++ llvm/test/DebugInfo/X86/op_deref.ll
@@ -27,6 +27,10 @@
 ; RUN: llvm-as %s -o - | llvm-dis - | FileCheck %s --check-prefix=PRETTY-PRINT
 ; PRETTY-PRINT: DIExpression()
 
+; XFAIL: *
+; See the for.body block, LiveDebugValues sees a stack load and moves the
+; variable location with it, rather than leaving it alone.
+
 define void @testVLAwithSize(i32 %s) nounwind uwtable ssp !dbg !5 {
 entry:
   %s.addr = alloca i32, align 4
@@ -56,6 +60,12 @@
   %mul = mul nsw i32 %5, %6, !dbg !23
   %7 = load i32, i32* %i, align 4, !dbg !23
   %idxprom = sext i32 %7 to i64, !dbg !23
+; XXX FIXME
+; The restore of vla here causes the stack location to be clobbered going
+; back around the loop. Ideally in the future, LLVM should be clever enough
+; to know that the variable location of vla is best left on the stack through
+; the body of the loop, rather than eagerly promoting it and losing it.
+; Some more example of poor decisions are in PR42834.
   %arrayidx = getelementptr inbounds i32, i32* %vla, i64 %idxprom, !dbg !23
   store i32 %mul, i32* %arrayidx, align 4, !dbg !23
   br label %for.inc, !dbg !25
Index: llvm/test/DebugInfo/X86/parameters.ll
===================================================================
--- llvm/test/DebugInfo/X86/parameters.ll
+++ llvm/test/DebugInfo/X86/parameters.ll
@@ -32,6 +32,7 @@
 ; CHECK-NOT: DW_TAG
 ; CHECK: DW_AT_name{{.*}} = "f"
 
+; Argument "g" enters in RSI, is spilt, then restored to RAX.
 ; CHECK: DW_TAG_subprogram
 ; CHECK: DW_AT_name{{.*}} = "func2"
 ; CHECK: DW_TAG_formal_parameter
@@ -39,7 +40,8 @@
 ; CHECK: DW_TAG_formal_parameter
 ; CHECK: DW_AT_location{{.*}}(
 ; CHECK-NEXT: {{.*}}: DW_OP_breg4 RSI+0{{$}}
-; CHECK-NEXT: {{.*}}: DW_OP_breg7 RSP+8, DW_OP_deref)
+; CHECK-NEXT: {{.*}}: DW_OP_breg7 RSP+8, DW_OP_deref{{$}}
+; CHECK-NEXT: {{.*}}: DW_OP_breg0 RAX+0){{$}}
 ; CHECK-NOT: DW_TAG
 ; CHECK: DW_AT_name{{.*}} = "g"
 
Index: llvm/test/DebugInfo/X86/pieces-4.ll
===================================================================
--- llvm/test/DebugInfo/X86/pieces-4.ll
+++ llvm/test/DebugInfo/X86/pieces-4.ll
@@ -17,7 +17,7 @@
 ; CHECK:               callq   g
 ; CHECK:               movl    %eax, [[offs:[0-9]+]](%rsp)          # 4-byte Spill
 ; CHECK:               #DEBUG_VALUE: bitpiece_spill:o <- [DW_OP_LLVM_fragment 32 32] 0
-; CHECK:               #DEBUG_VALUE: bitpiece_spill:o <- [DW_OP_plus_uconst [[offs]], DW_OP_LLVM_fragment 0 32] [$rsp+0]
+; CHECK:               #DEBUG_VALUE: bitpiece_spill:o <- [DW_OP_plus_uconst [[offs]], DW_OP_deref, DW_OP_LLVM_fragment 0 32] $rsp
 ; CHECK:               #APP
 ; CHECK:               #NO_APP
 ; CHECK:               movl    [[offs]](%rsp), %eax          # 4-byte Reload
Index: llvm/test/DebugInfo/X86/pr34545.ll
===================================================================
--- llvm/test/DebugInfo/X86/pr34545.ll
+++ llvm/test/DebugInfo/X86/pr34545.ll
@@ -1,10 +1,10 @@
-; RUN: llc -O1 -filetype=asm -mtriple x86_64-unknown-linux-gnu -mcpu=x86-64 -o - %s -stop-after=livedebugvars | FileCheck %s
+; RUN: llc -O1 -filetype=asm -mtriple x86_64-unknown-linux-gnu -mcpu=x86-64 -o - %s -stop-after=livedebugvalues | FileCheck %s
 
 ; CHECK: $eax = MOV32rm
 ; CHECK: DBG_VALUE $eax
 ; CHECK: $eax = SHL32rCL killed renamable $eax
 ; CHECK: DBG_VALUE $eax
-; CHECK: DBG_VALUE $rsp, 0, !{{[0-9]+}}, !DIExpression(DW_OP_constu, 4, DW_OP_minus)
+; CHECK: DBG_VALUE $rsp, $noreg, !{{[0-9]+}}, !DIExpression(DW_OP_constu, 4, DW_OP_minus, DW_OP_deref)
 ; CHECK: DBG_VALUE $eax
 ; CHECK: $eax = SHL32rCL killed renamable $eax
 ; CHECK: DBG_VALUE $eax
Index: llvm/test/DebugInfo/X86/prolog-params.mir
===================================================================
--- llvm/test/DebugInfo/X86/prolog-params.mir
+++ llvm/test/DebugInfo/X86/prolog-params.mir
@@ -147,10 +147,11 @@
 # CHECK-NEXT: DBG_VALUE $r9d, $noreg, ![[P5]], !DIExpression()
 # CHECK-NEXT: frame-setup PUSH64r
 
-# Locals and stack parameters are emitted after the prologue code.
-# CHECK: DBG_VALUE $rsp, 0, ![[P6]], !DIExpression(DW_OP_plus_uconst, 16)
+# Locals and stack parameters are emitted after the prologue code. The
+# second operand records their (negative) frame index, printed unsigned.
+# CHECK: DBG_VALUE $rsp, 4294967293, ![[P6]], !DIExpression()
 # CHECK-NEXT: DBG_VALUE $r9d, $noreg, ![[P6]], !DIExpression()
-# CHECK-NEXT: DBG_VALUE $rsp, 0, ![[P7]], !DIExpression(DW_OP_plus_uconst, 24)
-# CHECK-NEXT: DBG_VALUE $rsp, 0, ![[P8]], !DIExpression(DW_OP_plus_uconst, 32)
+# CHECK-NEXT: DBG_VALUE $rsp, 4294967294, ![[P7]], !DIExpression()
+# CHECK-NEXT: DBG_VALUE $rsp, 4294967295, ![[P8]], !DIExpression()
 # CHECK-NEXT: DBG_VALUE $edi, $noreg, ![[LOCAL1]], !DIExpression()
-# CHECK-NEXT: DBG_VALUE $rsp, 0, ![[LOCAL2]], !DIExpression(DW_OP_plus_uconst, 16)
+# CHECK-NEXT: DBG_VALUE $rsp, 4294967293, ![[LOCAL2]], !DIExpression()
Index: llvm/test/DebugInfo/X86/spill-indirect-nrvo.ll
===================================================================
--- llvm/test/DebugInfo/X86/spill-indirect-nrvo.ll
+++ llvm/test/DebugInfo/X86/spill-indirect-nrvo.ll
@@ -23,10 +23,12 @@
 ; CHECK-LABEL: _Z10get_stringv:
 ; CHECK: #DEBUG_VALUE: get_string:result <- [DW_OP_deref] $rdi
 ; CHECK: movq   %rdi, [[OFFS:[0-9]+]](%rsp)          # 8-byte Spill
-; CHECK: #DEBUG_VALUE: get_string:result <- [DW_OP_plus_uconst [[OFFS]], DW_OP_deref] [$rsp+0]
+; CHECK: #DEBUG_VALUE: get_string:result <- [DW_OP_plus_uconst [[OFFS]], DW_OP_deref, DW_OP_deref] $rsp
 ; CHECK: callq  _ZN6stringC1Ei
 ; CHECK: #APP
 ; CHECK: #NO_APP
+; CHECK: movq    [[OFFS]](%rsp), %[[LOADREG:r[abcds][xi]]]  # 8-byte Reload
+; CHECK: #DEBUG_VALUE: get_string:result <- [DW_OP_deref] $[[LOADREG]]
 
 ; ModuleID = 't.cpp'
 source_filename = "t.cpp"
Index: llvm/test/DebugInfo/X86/spill-nontrivial-param.ll
===================================================================
--- llvm/test/DebugInfo/X86/spill-nontrivial-param.ll
+++ llvm/test/DebugInfo/X86/spill-nontrivial-param.ll
@@ -22,7 +22,7 @@
 ; CHECK-LABEL: _Z3foo10NonTrivial:
 ; CHECK: #DEBUG_VALUE: foo:nt <- [DW_OP_deref] $rdi
 ; CHECK: movq    %rdi, -8(%rsp)          # 8-byte Spill
-; CHECK: #DEBUG_VALUE: foo:nt <- [DW_OP_constu 8, DW_OP_minus, DW_OP_deref] [$rsp+0]
+; CHECK: #DEBUG_VALUE: foo:nt <- [DW_OP_constu 8, DW_OP_minus, DW_OP_deref, DW_OP_deref] $rsp
 ; CHECK: #APP
 ; CHECK: #NO_APP
 ; CHECK: movq    -8(%rsp), %rax          # 8-byte Reload
Index: llvm/test/DebugInfo/X86/spill-nospill.ll
===================================================================
--- llvm/test/DebugInfo/X86/spill-nospill.ll
+++ llvm/test/DebugInfo/X86/spill-nospill.ll
@@ -24,7 +24,7 @@
 ; CHECK-LABEL: f: # @f
 ; CHECK: callq   g
 ; CHECK: movl    %eax, [[X_OFFS:[0-9]+]](%rsp)          # 4-byte Spill
-; CHECK: #DEBUG_VALUE: f:x <- [DW_OP_plus_uconst [[X_OFFS]]] [$rsp+0]
+; CHECK: #DEBUG_VALUE: f:x <- [DW_OP_plus_uconst [[X_OFFS]], DW_OP_deref] $rsp
 ; CHECK: #APP
 ; CHECK: #NO_APP
 ; CHECK: callq   g
Index: llvm/test/DebugInfo/X86/sret.ll
===================================================================
--- llvm/test/DebugInfo/X86/sret.ll
+++ llvm/test/DebugInfo/X86/sret.ll
@@ -3,8 +3,8 @@
 
 ; Based on the debuginfo-tests/sret.cpp code.
 
-; CHECK-DWO: DW_AT_GNU_dwo_id [DW_FORM_data8] (0x51ac5644b1937aa1)
-; CHECK-DWO: DW_AT_GNU_dwo_id [DW_FORM_data8] (0x51ac5644b1937aa1)
+; CHECK-DWO: DW_AT_GNU_dwo_id [DW_FORM_data8] (0x29bc2656bdb2e5dc)
+; CHECK-DWO: DW_AT_GNU_dwo_id [DW_FORM_data8] (0x29bc2656bdb2e5dc)
 
 ; RUN: llc -O0 -fast-isel=true -mtriple=x86_64-apple-darwin -filetype=obj -o - %s | llvm-dwarfdump -v - | FileCheck %s
 ; RUN: llc -O0 -fast-isel=false -mtriple=x86_64-apple-darwin -filetype=obj -o - %s | llvm-dwarfdump -v - | FileCheck %s
@@ -12,7 +12,8 @@
 ; CHECK: DW_TAG_variable
 ; CHECK-NEXT:   DW_AT_location [DW_FORM_sec_offset] (0x00000000
 ; CHECK-NEXT:     [{{.*}}, {{.*}}): DW_OP_breg5 RDI+0
-; CHECK-NEXT:     [{{.*}}, {{.*}}): DW_OP_breg6 RBP-24, DW_OP_deref)
+; CHECK-NEXT:     [{{.*}}, {{.*}}): DW_OP_breg6 RBP-24, DW_OP_deref
+; CHECK-NEXT:     [{{.*}}, {{.*}}): DW_OP_breg5 RDI+0
 ; CHECK-NEXT:   DW_AT_name {{.*}}"a"
 
 %class.A = type { i32 (...)**, i32 }