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/ARM/ARMISelDAGToDAG.cpp b/llvm/lib/Target/ARM/ARMISelDAGToDAG.cpp
index 0ee5944..ab20e4d 100644
--- a/llvm/lib/Target/ARM/ARMISelDAGToDAG.cpp
+++ b/llvm/lib/Target/ARM/ARMISelDAGToDAG.cpp
@@ -1232,9 +1232,9 @@
     int FI = cast<FrameIndexSDNode>(N)->getIndex();
     // Only multiples of 4 are allowed for the offset, so the frame object
     // alignment must be at least 4.
-    MachineFrameInfo *MFI = MF->getFrameInfo();
-    if (MFI->getObjectAlignment(FI) < 4)
-      MFI->setObjectAlignment(FI, 4);
+    MachineFrameInfo &MFI = MF->getFrameInfo();
+    if (MFI.getObjectAlignment(FI) < 4)
+      MFI.setObjectAlignment(FI, 4);
     Base = CurDAG->getTargetFrameIndex(
         FI, TLI->getPointerTy(CurDAG->getDataLayout()));
     OffImm = CurDAG->getTargetConstant(0, SDLoc(N), MVT::i32);
@@ -1255,9 +1255,9 @@
         int FI = cast<FrameIndexSDNode>(Base)->getIndex();
         // For LHS+RHS to result in an offset that's a multiple of 4 the object
         // indexed by the LHS must be 4-byte aligned.
-        MachineFrameInfo *MFI = MF->getFrameInfo();
-        if (MFI->getObjectAlignment(FI) < 4)
-          MFI->setObjectAlignment(FI, 4);
+        MachineFrameInfo &MFI = MF->getFrameInfo();
+        if (MFI.getObjectAlignment(FI) < 4)
+          MFI.setObjectAlignment(FI, 4);
         Base = CurDAG->getTargetFrameIndex(
             FI, TLI->getPointerTy(CurDAG->getDataLayout()));
       }
@@ -2765,9 +2765,9 @@
     if (Subtarget->isThumb1Only()) {
       // Set the alignment of the frame object to 4, to avoid having to generate
       // more than one ADD
-      MachineFrameInfo *MFI = MF->getFrameInfo();
-      if (MFI->getObjectAlignment(FI) < 4)
-        MFI->setObjectAlignment(FI, 4);
+      MachineFrameInfo &MFI = MF->getFrameInfo();
+      if (MFI.getObjectAlignment(FI) < 4)
+        MFI.setObjectAlignment(FI, 4);
       CurDAG->SelectNodeTo(N, ARM::tADDframe, MVT::i32, TFI,
                            CurDAG->getTargetConstant(0, dl, MVT::i32));
       return;