Add basic ability to setup call frame, and make procedure calls.
Hello world will compile and execute with this patch.

Patch by Reed Kotler.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@160651 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/Mips/MipsISelLowering.cpp b/lib/Target/Mips/MipsISelLowering.cpp
index 6b80e3f..7741f9f 100644
--- a/lib/Target/Mips/MipsISelLowering.cpp
+++ b/lib/Target/Mips/MipsISelLowering.cpp
@@ -2645,6 +2645,7 @@
   SmallVector<ISD::InputArg, 32> &Ins   = CLI.Ins;
   SDValue InChain                       = CLI.Chain;
   SDValue Callee                        = CLI.Callee;
+  SDValue CalleeSave                    = CLI.Callee;
   bool &isTailCall                      = CLI.IsTailCall;
   CallingConv::ID CallConv              = CLI.CallConv;
   bool isVarArg                         = CLI.IsVarArg;
@@ -2901,7 +2902,7 @@
   SDVTList NodeTys = DAG.getVTList(MVT::Other, MVT::Glue);
   SmallVector<SDValue, 8> Ops;
   Ops.push_back(Chain);
-  Ops.push_back(Callee);
+  Ops.push_back(Subtarget->inMips16Mode()? CalleeSave: Callee);
 
   // Add argument registers to the end of the list so that they are
   // known live into the call.
@@ -2909,6 +2910,8 @@
     Ops.push_back(DAG.getRegister(RegsToPass[i].first,
                                   RegsToPass[i].second.getValueType()));
 
+  if (Subtarget->inMips16Mode())
+    Ops.push_back(Callee);
   // Add a register mask operand representing the call-preserved registers.
   const TargetRegisterInfo *TRI = getTargetMachine().getRegisterInfo();
   const uint32_t *Mask = TRI->getCallPreservedMask(CallConv);