5 files changed, 22 insertions, 5 deletions
diff --git a/llvm/lib/CodeGen/MIRParser/MIRParser.cpp b/llvm/lib/CodeGen/MIRParser/MIRParser.cpp
index 78b57f35778..d0b46c4668b 100644
--- a/llvm/lib/CodeGen/MIRParser/MIRParser.cpp
+++ b/llvm/lib/CodeGen/MIRParser/MIRParser.cpp
@@ -587,6 +587,7 @@ bool MIRParserImpl::initializeFrameInfo(PerFunctionMIParsingState &PFS,
     else
       ObjectIdx = MFI.CreateFixedSpillStackObject(Object.Size, Object.Offset);
     MFI.setObjectAlignment(ObjectIdx, Object.Alignment);
+    MFI.setStackID(ObjectIdx, Object.StackID);
     if (!PFS.FixedStackObjectSlots.insert(std::make_pair(Object.ID.Value,
                                                          ObjectIdx))
              .second)
@@ -619,6 +620,8 @@ bool MIRParserImpl::initializeFrameInfo(PerFunctionMIParsingState &PFS,
           Object.Size, Object.Alignment,
           Object.Type == yaml::MachineStackObject::SpillSlot, Alloca);
     MFI.setObjectOffset(ObjectIdx, Object.Offset);
+    MFI.setStackID(ObjectIdx, Object.StackID);
+
     if (!PFS.StackObjectSlots.insert(std::make_pair(Object.ID.Value, ObjectIdx))
              .second)
       return error(Object.ID.SourceRange.Start,
diff --git a/llvm/lib/CodeGen/MIRPrinter.cpp b/llvm/lib/CodeGen/MIRPrinter.cpp
index ddeacf1d1bf..b9281b1e5e1 100644
--- a/llvm/lib/CodeGen/MIRPrinter.cpp
+++ b/llvm/lib/CodeGen/MIRPrinter.cpp
@@ -366,6 +366,7 @@ void MIRPrinter::convertStackObjects(yaml::MachineFunction &YMF,
     YamlObject.Offset = MFI.getObjectOffset(I);
     YamlObject.Size = MFI.getObjectSize(I);
     YamlObject.Alignment = MFI.getObjectAlignment(I);
+    YamlObject.StackID = MFI.getStackID(I);
     YamlObject.IsImmutable = MFI.isImmutableObjectIndex(I);
     YamlObject.IsAliased = MFI.isAliasedObjectIndex(I);
     YMF.FixedStackObjects.push_back(YamlObject);
@@ -392,6 +393,7 @@ void MIRPrinter::convertStackObjects(yaml::MachineFunction &YMF,
     YamlObject.Offset = MFI.getObjectOffset(I);
     YamlObject.Size = MFI.getObjectSize(I);
     YamlObject.Alignment = MFI.getObjectAlignment(I);
+    YamlObject.StackID = MFI.getStackID(I);
 
     YMF.StackObjects.push_back(YamlObject);
     StackObjectOperandMapping.insert(std::make_pair(
diff --git a/llvm/lib/CodeGen/MachineFrameInfo.cpp b/llvm/lib/CodeGen/MachineFrameInfo.cpp
index 73d778ff302..be8adf75fb7 100644
--- a/llvm/lib/CodeGen/MachineFrameInfo.cpp
+++ b/llvm/lib/CodeGen/MachineFrameInfo.cpp
@@ -47,11 +47,12 @@ static inline unsigned clampStackAlignment(bool ShouldClamp, unsigned Align,
 }
 
 int MachineFrameInfo::CreateStackObject(uint64_t Size, unsigned Alignment,
-                      bool isSS, const AllocaInst *Alloca) {
+                                        bool isSS, const AllocaInst *Alloca,
+                                        uint8_t ID) {
   assert(Size != 0 && "Cannot allocate zero size stack objects!");
   Alignment = clampStackAlignment(!StackRealignable, Alignment, StackAlignment);
   Objects.push_back(StackObject(Size, Alignment, 0, false, isSS, Alloca,
-                                !isSS));
+                                !isSS, ID));
   int Index = (int)Objects.size() - NumFixedObjects - 1;
   assert(Index >= 0 && "Bad frame index!");
   ensureMaxAlignment(Alignment);
@@ -212,6 +213,10 @@ void MachineFrameInfo::print(const MachineFunction &MF, raw_ostream &OS) const{
   for (unsigned i = 0, e = Objects.size(); i != e; ++i) {
     const StackObject &SO = Objects[i];
     OS << "  fi#" << (int)(i-NumFixedObjects) << ": ";
+
+    if (SO.StackID != 0)
+      OS << "id=" << SO.StackID << ' ';
+
     if (SO.Size == ~0ULL) {
       OS << "dead\n";
       continue;
diff --git a/llvm/lib/CodeGen/MachineInstr.cpp b/llvm/lib/CodeGen/MachineInstr.cpp
index 017352abb32..b49df4706b7 100644
--- a/llvm/lib/CodeGen/MachineInstr.cpp
+++ b/llvm/lib/CodeGen/MachineInstr.cpp
@@ -609,8 +609,9 @@ MachinePointerInfo MachinePointerInfo::getGOT(MachineFunction &MF) {
 }
 
 MachinePointerInfo MachinePointerInfo::getStack(MachineFunction &MF,
-                                                int64_t Offset) {
-  return MachinePointerInfo(MF.getPSVManager().getStack(), Offset);
+                                                int64_t Offset,
+                                                uint8_t ID) {
+  return MachinePointerInfo(MF.getPSVManager().getStack(), Offset,ID);
 }
 
 MachineMemOperand::MachineMemOperand(MachinePointerInfo ptrinfo, Flags f,
diff --git a/llvm/lib/CodeGen/StackSlotColoring.cpp b/llvm/lib/CodeGen/StackSlotColoring.cpp
index 856bca19dee..6bdff4fa2e2 100644
--- a/llvm/lib/CodeGen/StackSlotColoring.cpp
+++ b/llvm/lib/CodeGen/StackSlotColoring.cpp
@@ -233,6 +233,8 @@ StackSlotColoring::OverlapWithAssignments(LiveInterval *li, int Color) const {
 int StackSlotColoring::ColorSlot(LiveInterval *li) {
   int Color = -1;
   bool Share = false;
+  int FI = TargetRegisterInfo::stackSlot2Index(li->reg);
+
   if (!DisableSharing) {
     // Check if it's possible to reuse any of the used colors.
     Color = UsedColors.find_first();
@@ -246,6 +248,11 @@ int StackSlotColoring::ColorSlot(LiveInterval *li) {
     }
   }
 
+  if (Color != -1 && MFI->getStackID(Color) != MFI->getStackID(FI)) {
+    DEBUG(dbgs() << "cannot share FIs with different stack IDs\n");
+    Share = false;
+  }
+
   // Assign it to the first available color (assumed to be the best) if it's
   // not possible to share a used color with other objects.
   if (!Share) {
@@ -257,7 +264,6 @@ int StackSlotColoring::ColorSlot(LiveInterval *li) {
 
   // Record the assignment.
   Assignments[Color].push_back(li);
-  int FI = TargetRegisterInfo::stackSlot2Index(li->reg);
   DEBUG(dbgs() << "Assigning fi#" << FI << " to fi#" << Color << "\n");
 
   // Change size and alignment of the allocated slot. If there are multiple