MachineFunction: Return reference for getFrameInfo(); NFC

getFrameInfo() never returns nullptr so we should use a reference
instead of a pointer.

llvm-svn: 277017
diff --git a/llvm/lib/Target/PowerPC/PPCInstrInfo.cpp b/llvm/lib/Target/PowerPC/PPCInstrInfo.cpp
index f25bc52..fbbbfc4 100644
--- a/llvm/lib/Target/PowerPC/PPCInstrInfo.cpp
+++ b/llvm/lib/Target/PowerPC/PPCInstrInfo.cpp
@@ -1079,7 +1079,7 @@
   for (unsigned i = 0, e = NewMIs.size(); i != e; ++i)
     MBB.insert(MI, NewMIs[i]);
 
-  const MachineFrameInfo &MFI = *MF.getFrameInfo();
+  const MachineFrameInfo &MFI = MF.getFrameInfo();
   MachineMemOperand *MMO = MF.getMachineMemOperand(
       MachinePointerInfo::getFixedStack(MF, FrameIdx),
       MachineMemOperand::MOStore, MFI.getObjectSize(FrameIdx),
@@ -1190,7 +1190,7 @@
   for (unsigned i = 0, e = NewMIs.size(); i != e; ++i)
     MBB.insert(MI, NewMIs[i]);
 
-  const MachineFrameInfo &MFI = *MF.getFrameInfo();
+  const MachineFrameInfo &MFI = MF.getFrameInfo();
   MachineMemOperand *MMO = MF.getMachineMemOperand(
       MachinePointerInfo::getFixedStack(MF, FrameIdx),
       MachineMemOperand::MOLoad, MFI.getObjectSize(FrameIdx),