Index: lib/Target/Mips/MipsSEISelDAGToDAG.h
===================================================================
--- lib/Target/Mips/MipsSEISelDAGToDAG.h
+++ lib/Target/Mips/MipsSEISelDAGToDAG.h
@@ -32,6 +32,8 @@
 
   void addDSPCtrlRegOperands(bool IsDef, MachineInstr &MI,
                              MachineFunction &MF);
+  
+  void addCOPYNodeSW16_MM(MachineFunction &MF, MachineInstr &MI);
 
   unsigned getMSACtrlReg(const SDValue RegIdx) const;
 
Index: lib/Target/Mips/MipsSEISelDAGToDAG.cpp
===================================================================
--- lib/Target/Mips/MipsSEISelDAGToDAG.cpp
+++ lib/Target/Mips/MipsSEISelDAGToDAG.cpp
@@ -49,6 +49,25 @@
   SelectionDAGISel::getAnalysisUsage(AU);
 }
 
+void
+MipsSEDAGToDAGISel::addCOPYNodeSW16_MM(MachineFunction &MF, MachineInstr &MI) {
+  MachineBasicBlock &MBB = *MI.getParent();
+  const TargetRegisterInfo *TRI = Subtarget->getRegisterInfo();
+  const TargetInstrInfo *TII = Subtarget->getInstrInfo();
+  MachineRegisterInfo &RegInfo = MF.getRegInfo();
+  DebugLoc DL = MI.getDebugLoc();
+  MachineBasicBlock::iterator II(MI);
+
+  unsigned Reg = MI.getOperand(0).getReg();
+  const auto &GPRMM16ZeroRegClass =
+      TRI->getRegClass(Mips::GPRMM16ZeroRegClassID);
+  unsigned NewReg = RegInfo.createVirtualRegister(GPRMM16ZeroRegClass);
+
+  BuildMI(MBB, II, DL, TII->get(Mips::COPY), NewReg).addReg(Reg);
+  
+  MI.getOperand(0).setReg(NewReg);
+}
+
 void MipsSEDAGToDAGISel::addDSPCtrlRegOperands(bool IsDef, MachineInstr &MI,
                                                MachineFunction &MF) {
   MachineInstrBuilder MIB(MF, &MI);
@@ -238,6 +257,9 @@
       case Mips::WRDSP:
         addDSPCtrlRegOperands(true, MI, MF);
         break;
+      case Mips::SW16_MM:
+        addCOPYNodeSW16_MM(MF, MI);
+        break;
       default:
         replaceUsesWithZeroReg(MRI, MI);
       }
Index: test/CodeGen/Mips/tailcall/tailcall.ll
===================================================================
--- test/CodeGen/Mips/tailcall/tailcall.ll
+++ test/CodeGen/Mips/tailcall/tailcall.ll
@@ -10,27 +10,27 @@
 ; RUN:      -verify-machineinstrs -mips-tail-calls=1 < %s | \
 ; RUN:     FileCheck %s -check-prefixes=ALL,PIC16
 
-; RUN: llc -march=mipsel -relocation-model=pic -mattr=+micromips -mips-tail-calls=1 < %s | \
-; RUN:     FileCheck %s -check-prefixes=ALL,PIC32MM
-; RUN: llc -march=mipsel -relocation-model=static -mattr=+micromips \
+; RUN: llc -march=mipsel -relocation-model=pic -mattr=+micromips -verify-machineinstrs \
+; RUN:     -mips-tail-calls=1 < %s | FileCheck %s -check-prefixes=ALL,PIC32MM
+; RUN: llc -march=mipsel -relocation-model=static -mattr=+micromips -verify-machineinstrs \
 ; RUN:     -mips-tail-calls=1 < %s | FileCheck %s -check-prefixes=ALL,STATIC32
 
-; RUN: llc -march=mipsel -relocation-model=pic -mcpu=mips32r6 -mips-tail-calls=1 < %s | \
-; RUN:     FileCheck %s -check-prefixes=ALL,PIC32R6
-; RUN: llc -march=mipsel -relocation-model=static -mcpu=mips32r2 \
+; RUN: llc -march=mipsel -relocation-model=pic -mcpu=mips32r6 -mips-tail-calls=1 < %s \
+; RUN:     -verify-machineinstrs | FileCheck %s -check-prefixes=ALL,PIC32R6
+; RUN: llc -march=mipsel -relocation-model=static -mcpu=mips32r2 -verify-machineinstrs \
 ; RUN:     -mips-tail-calls=1 < %s | FileCheck %s -check-prefixes=ALL,STATIC32
-; RUN: llc -march=mips64el -relocation-model=pic -mcpu=mips64r2  \
+; RUN: llc -march=mips64el -relocation-model=pic -mcpu=mips64r2 -verify-machineinstrs \
 ; RUN:     -mips-tail-calls=1 < %s | FileCheck %s -check-prefix=PIC64
-; RUN: llc -march=mips64el -relocation-model=pic -mcpu=mips64r6  \
+; RUN: llc -march=mips64el -relocation-model=pic -mcpu=mips64r6 -verify-machineinstrs \
 ; RUN:     -mips-tail-calls=1 < %s | FileCheck %s -check-prefix=STATIC64
 
-; RUN: llc -march=mipsel -relocation-model=pic -mcpu=mips32r6 -mattr=+micromips \
+; RUN: llc -march=mipsel -relocation-model=pic -mcpu=mips32r6 -mattr=+micromips -verify-machineinstrs \
 ; RUN:      -mips-tail-calls=1 < %s | FileCheck %s -check-prefixes=ALL,PIC32MM
-; RUN: llc -march=mipsel -relocation-model=static -mcpu=mips32r6 \
+; RUN: llc -march=mipsel -relocation-model=static -mcpu=mips32r6 -verify-machineinstrs \
 ; RUN:     -mattr=+micromips -mips-tail-calls=1 < %s | FileCheck %s -check-prefixes=ALL,STATIC32
-; RUN: llc -march=mips64el -relocation-model=pic -mcpu=mips64r6 \
+; RUN: llc -march=mips64el -relocation-model=pic -mcpu=mips64r6 -verify-machineinstrs \
 ; RUN:     -mattr=+micromips -mips-tail-calls=1 < %s | FileCheck %s -check-prefix=PIC64R6MM
-; RUN: llc -march=mips64el -relocation-model=static -mcpu=mips64r6 \
+; RUN: llc -march=mips64el -relocation-model=static -mcpu=mips64r6 -verify-machineinstrs \
 ; RUN:     -mattr=+micromips -mips-tail-calls=1 < %s | FileCheck %s -check-prefix=STATIC64
 
 @g0 = common global i32 0, align 4