1 files changed, 31 insertions, 0 deletions
diff --git a/lib/Target/Mips/MipsInstrInfo.cpp b/lib/Target/Mips/MipsInstrInfo.cpp
index 30d6805..130bfb8 100644
--- a/lib/Target/Mips/MipsInstrInfo.cpp
+++ b/lib/Target/Mips/MipsInstrInfo.cpp
@@ -371,6 +371,37 @@ void MipsInstrInfo::loadRegFromAddr(MachineFunction &MF, unsigned DestReg,
   return;
 }
 
+MachineInstr *MipsInstrInfo::
+foldMemoryOperand(MachineInstr* MI,
+                  SmallVectorImpl<unsigned> &Ops, int FI) const 
+{
+  if (Ops.size() != 1) return NULL;
+
+  MachineInstr *NewMI = NULL;
+
+  switch (MI->getOpcode()) 
+  {
+    case Mips::ADDu:
+      if ((MI->getOperand(0).isRegister()) &&
+        (MI->getOperand(1).isRegister()) && 
+        (MI->getOperand(1).getReg() == Mips::ZERO) &&
+        (MI->getOperand(2).isRegister())) 
+      {
+        if (Ops[0] == 0)    // COPY -> STORE
+          NewMI = BuildMI(get(Mips::SW)).addFrameIndex(FI)
+                  .addImm(0).addReg(MI->getOperand(2).getReg());
+        else                   // COPY -> LOAD
+          NewMI = BuildMI(get(Mips::LW), MI->getOperand(0)
+                  .getReg()).addImm(0).addFrameIndex(FI);
+      }
+      break;
+  }
+
+  if (NewMI)
+    NewMI->copyKillDeadInfo(MI);
+  return NewMI;
+}
+
 unsigned MipsInstrInfo::
 RemoveBranch(MachineBasicBlock &MBB) const 
 {