Add an ID field to StackObjects

On AMDGPU SGPR spills are really spilled to another register.
The spiller creates the spills to new frame index objects,
which is used as a placeholder.

This will eventually be replaced with a reference to a position
in a VGPR to write to and the frame index deleted. It is
most likely not a real stack location that can be shared
with another stack object.

This is a problem when StackSlotColoring decides it should
combine a frame index used for a normal VGPR spill with
a real stack location and a frame index used for an SGPR.

Add an ID field so that StackSlotColoring has a way
of knowing the different frame index types are
incompatible.

llvm-svn: 308673

1 files changed, 7 insertions, 2 deletions

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;