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/MipsMachineFunction.cpp b/lib/Target/Mips/MipsMachineFunction.cpp
index e3746d4..362173e 100644
--- a/lib/Target/Mips/MipsMachineFunction.cpp
+++ b/lib/Target/Mips/MipsMachineFunction.cpp
@@ -33,10 +33,13 @@
 
   const MipsSubtarget &ST = MF.getTarget().getSubtarget<MipsSubtarget>();
 
-  const TargetRegisterClass *RC = ST.isABI_N64() ?
-    (const TargetRegisterClass*)&Mips::CPU64RegsRegClass :
-    (const TargetRegisterClass*)&Mips::CPURegsRegClass;
-
+  const TargetRegisterClass *RC;
+  if (ST.inMips16Mode())
+    RC=(const TargetRegisterClass*)&Mips::CPU16RegsRegClass;
+  else
+    RC = ST.isABI_N64() ?
+      (const TargetRegisterClass*)&Mips::CPU64RegsRegClass :
+      (const TargetRegisterClass*)&Mips::CPURegsRegClass;
   return GlobalBaseReg = MF.getRegInfo().createVirtualRegister(RC);
 }