diff --git a/lib/Target/Mips/MipsISelLowering.cpp b/lib/Target/Mips/MipsISelLowering.cpp
index 94e18689b73..b485b5ea16d 100644
--- a/lib/Target/Mips/MipsISelLowering.cpp
+++ b/lib/Target/Mips/MipsISelLowering.cpp
@@ -212,8 +212,14 @@ MipsTargetLowering(MipsTargetMachine &TM)
   setOperationAction(ISD::VASTART,            MVT::Other, Custom);
   setOperationAction(ISD::FCOPYSIGN,          MVT::f32,   Custom);
   setOperationAction(ISD::FCOPYSIGN,          MVT::f64,   Custom);
-  setOperationAction(ISD::MEMBARRIER,         MVT::Other, Custom);
-  setOperationAction(ISD::ATOMIC_FENCE,       MVT::Other, Custom);
+  if (Subtarget->inMips16Mode()) {
+    setOperationAction(ISD::MEMBARRIER,         MVT::Other, Expand);
+    setOperationAction(ISD::ATOMIC_FENCE,       MVT::Other, Expand);
+  }
+  else {
+    setOperationAction(ISD::MEMBARRIER,         MVT::Other, Custom);
+    setOperationAction(ISD::ATOMIC_FENCE,       MVT::Other, Custom);
+  }
   if (!Subtarget->inMips16Mode()) {
     setOperationAction(ISD::LOAD,               MVT::i32, Custom);
     setOperationAction(ISD::STORE,              MVT::i32, Custom);
@@ -320,6 +326,21 @@ MipsTargetLowering(MipsTargetMachine &TM)
   setOperationAction(ISD::ATOMIC_STORE,      MVT::i32,    Expand);
   setOperationAction(ISD::ATOMIC_STORE,      MVT::i64,    Expand);
 
+  if (Subtarget->inMips16Mode()) {
+    setOperationAction(ISD::ATOMIC_CMP_SWAP,       MVT::i32,    Expand);
+    setOperationAction(ISD::ATOMIC_SWAP,           MVT::i32,    Expand);
+    setOperationAction(ISD::ATOMIC_LOAD_ADD,       MVT::i32,    Expand);
+    setOperationAction(ISD::ATOMIC_LOAD_SUB,       MVT::i32,    Expand);
+    setOperationAction(ISD::ATOMIC_LOAD_AND,       MVT::i32,    Expand);
+    setOperationAction(ISD::ATOMIC_LOAD_OR,        MVT::i32,    Expand);
+    setOperationAction(ISD::ATOMIC_LOAD_XOR,       MVT::i32,    Expand);
+    setOperationAction(ISD::ATOMIC_LOAD_NAND,      MVT::i32,    Expand);
+    setOperationAction(ISD::ATOMIC_LOAD_MIN,       MVT::i32,    Expand);
+    setOperationAction(ISD::ATOMIC_LOAD_MAX,       MVT::i32,    Expand);
+    setOperationAction(ISD::ATOMIC_LOAD_UMIN,      MVT::i32,    Expand);
+    setOperationAction(ISD::ATOMIC_LOAD_UMAX,      MVT::i32,    Expand);
+  }
+
   setInsertFencesForAtomic(true);
 
   if (!Subtarget->hasSEInReg()) {
diff --git a/test/CodeGen/Mips/atomicops.ll b/test/CodeGen/Mips/atomicops.ll
new file mode 100644
index 00000000000..b9c3804e0d7
--- /dev/null
+++ b/test/CodeGen/Mips/atomicops.ll
@@ -0,0 +1,40 @@
+; RUN: llc  -march=mipsel -mcpu=mips16 -relocation-model=pic -O3 < %s | FileCheck %s -check-prefix=16
+
+@.str = private unnamed_addr constant [8 x i8] c"%d, %d\0A\00", align 1
+
+define i32 @foo(i32* %mem, i32 %val, i32 %c) nounwind {
+entry:
+  %0 = atomicrmw add i32* %mem, i32 %val seq_cst
+  %add = add nsw i32 %0, %c
+  ret i32 %add
+; 16: foo:
+; 16:	lw	${{[0-9]+}}, %call16(__sync_synchronize)(${{[0-9]+}})
+; 16: 	lw	${{[0-9]+}}, %call16(__sync_fetch_and_add_4)(${{[0-9]+}})
+}
+
+define i32 @main() nounwind {
+entry:
+  %x = alloca i32, align 4
+  store volatile i32 0, i32* %x, align 4
+  %0 = atomicrmw add i32* %x, i32 1 seq_cst
+  %add.i = add nsw i32 %0, 2
+  %1 = load volatile i32* %x, align 4
+  %call1 = call i32 (i8*, ...)* @printf(i8* getelementptr inbounds ([8 x i8]* @.str, i32 0, i32 0), i32 %add.i, i32 %1) nounwind
+  %2 = cmpxchg i32* %x, i32 1, i32 2 seq_cst
+  %3 = load volatile i32* %x, align 4
+  %call2 = call i32 (i8*, ...)* @printf(i8* getelementptr inbounds ([8 x i8]* @.str, i32 0, i32 0), i32 %2, i32 %3) nounwind
+  %4 = atomicrmw xchg i32* %x, i32 1 seq_cst
+  %5 = load volatile i32* %x, align 4
+  %call3 = call i32 (i8*, ...)* @printf(i8* getelementptr inbounds ([8 x i8]* @.str, i32 0, i32 0), i32 %4, i32 %5) nounwind
+; 16: main:
+; 16:	lw	${{[0-9]+}}, %call16(__sync_synchronize)(${{[0-9]+}})
+; 16: 	lw	${{[0-9]+}}, %call16(__sync_fetch_and_add_4)(${{[0-9]+}})
+; 16:	lw	${{[0-9]+}}, %call16(__sync_val_compare_and_swap_4)(${{[0-9]+}})
+; 16:	lw	${{[0-9]+}}, %call16(__sync_lock_test_and_set_4)(${{[0-9]+}})
+
+  ret i32 0
+}
+
+declare i32 @printf(i8* nocapture, ...) nounwind
+
+