Index: llvm/trunk/lib/Target/Mips/MipsISelLowering.cpp
===================================================================
--- llvm/trunk/lib/Target/Mips/MipsISelLowering.cpp
+++ llvm/trunk/lib/Target/Mips/MipsISelLowering.cpp
@@ -221,9 +221,23 @@
     setLoadExtAction(ISD::SEXTLOAD, VT, MVT::i1,  Promote);
   }
 
-  // MIPS doesn't have extending float->double load/store
-  for (MVT VT : MVT::fp_valuetypes())
+  // MIPS doesn't have extending float->double load/store.  Set LoadExtAction
+  // for f32, f16
+  for (MVT VT : MVT::fp_valuetypes()) {
     setLoadExtAction(ISD::EXTLOAD, VT, MVT::f32, Expand);
+    setLoadExtAction(ISD::EXTLOAD, VT, MVT::f16, Expand);
+  }
+
+  // Set LoadExtAction for f16 vectors to Expand
+  for (MVT VT : MVT::fp_vector_valuetypes()) {
+    MVT F16VT = MVT::getVectorVT(MVT::f16, VT.getVectorNumElements());
+    if (F16VT.isValid())
+      setLoadExtAction(ISD::EXTLOAD, VT, F16VT, Expand);
+  }
+
+  setTruncStoreAction(MVT::f32, MVT::f16, Expand);
+  setTruncStoreAction(MVT::f64, MVT::f16, Expand);
+
   setTruncStoreAction(MVT::f64, MVT::f32, Expand);
 
   // Used by legalize types to correctly generate the setcc result.
@@ -339,6 +353,12 @@
   setOperationAction(ISD::FREM,              MVT::f32,   Expand);
   setOperationAction(ISD::FREM,              MVT::f64,   Expand);
 
+  // Lower f16 conversion operations into library calls
+  setOperationAction(ISD::FP16_TO_FP,        MVT::f32,   Expand);
+  setOperationAction(ISD::FP_TO_FP16,        MVT::f32,   Expand);
+  setOperationAction(ISD::FP16_TO_FP,        MVT::f64,   Expand);
+  setOperationAction(ISD::FP_TO_FP16,        MVT::f64,   Expand);
+
   setOperationAction(ISD::EH_RETURN, MVT::Other, Custom);
 
   setOperationAction(ISD::VASTART,           MVT::Other, Custom);
Index: llvm/trunk/test/CodeGen/Mips/fp16-promote.ll
===================================================================
--- llvm/trunk/test/CodeGen/Mips/fp16-promote.ll
+++ llvm/trunk/test/CodeGen/Mips/fp16-promote.ll
@@ -0,0 +1,96 @@
+; RUN: llc -asm-verbose=false -mtriple=mipsel-linux-gnueabi < %s | FileCheck %s -check-prefix=CHECK-LIBCALL
+
+; CHECK-LIBCALL-LABEL: test_fadd:
+; CHECK-LIBCALL: %call16(__gnu_h2f_ieee)
+; CHECK-LIBCALL: %call16(__gnu_h2f_ieee)
+; CHECK-LIBCALL-DAG: add.s
+; CHECK-LIBCALL-DAG: %call16(__gnu_f2h_ieee)
+define void @test_fadd(half* %p, half* %q) #0 {
+  %a = load half, half* %p, align 2
+  %b = load half, half* %q, align 2
+  %r = fadd half %a, %b
+  store half %r, half* %p
+  ret void
+}
+
+; CHECK-LIBCALL-LABEL: test_fpext_float:
+; CHECK-LIBCALL: %call16(__gnu_h2f_ieee)
+define float @test_fpext_float(half* %p) {
+  %a = load half, half* %p, align 2
+  %r = fpext half %a to float
+  ret float %r
+}
+
+; CHECK-LIBCALL-LABEL: test_fpext_double:
+; CHECK-LIBCALL: %call16(__gnu_h2f_ieee)
+; CHECK-LIBCALL: cvt.d.s
+define double @test_fpext_double(half* %p) {
+  %a = load half, half* %p, align 2
+  %r = fpext half %a to double
+  ret double %r
+}
+
+; CHECK-LIBCALL-LABEL: test_fptrunc_float:
+; CHECK-LIBCALL: %call16(__gnu_f2h_ieee)
+define void @test_fptrunc_float(float %f, half* %p) #0 {
+  %a = fptrunc float %f to half
+  store half %a, half* %p
+  ret void
+}
+
+; CHECK-LIBCALL-LABEL: test_fptrunc_double:
+; CHECK-LIBCALL: %call16(__truncdfhf2)
+define void @test_fptrunc_double(double %d, half* %p) #0 {
+  %a = fptrunc double %d to half
+  store half %a, half* %p
+  ret void
+}
+
+; CHECK-LIBCALL-LABEL: test_vec_fpext_float:
+; CHECK-LIBCALL: %call16(__gnu_h2f_ieee)
+; CHECK-LIBCALL: %call16(__gnu_h2f_ieee)
+; CHECK-LIBCALL: %call16(__gnu_h2f_ieee)
+; CHECK-LIBCALL: %call16(__gnu_h2f_ieee)
+define <4 x float> @test_vec_fpext_float(<4 x half>* %p) #0 {
+  %a = load <4 x half>, <4 x half>* %p, align 8
+  %b = fpext <4 x half> %a to <4 x float>
+  ret <4 x float> %b
+}
+
+; CHECK-LIBCALL-LABEL: test_vec_fpext_double:
+; CHECK-LIBCALL-DAG: %call16(__gnu_h2f_ieee)
+; CHECK-LIBCALL-DAG: %call16(__gnu_h2f_ieee)
+; CHECK-LIBCALL-DAG: %call16(__gnu_h2f_ieee)
+; CHECK-LIBCALL-DAG: %call16(__gnu_h2f_ieee)
+; CHECK-LIBCALL-DAG: cvt.d.s
+; CHECK-LIBCALL-DAG: cvt.d.s
+; CHECK-LIBCALL-DAG: cvt.d.s
+; CHECK-LIBCALL: cvt.d.s
+define <4 x double> @test_vec_fpext_double(<4 x half>* %p) #0 {
+  %a = load <4 x half>, <4 x half>* %p, align 8
+  %b = fpext <4 x half> %a to <4 x double>
+  ret <4 x double> %b
+}
+
+; CHECK-LIBCALL-LABEL: test_vec_fptrunc_float:
+; CHECK-LIBCALL: %call16(__gnu_f2h_ieee)
+; CHECK-LIBCALL: %call16(__gnu_f2h_ieee)
+; CHECK-LIBCALL: %call16(__gnu_f2h_ieee)
+; CHECK-LIBCALL: %call16(__gnu_f2h_ieee)
+define void @test_vec_fptrunc_float(<4 x float> %a, <4 x half>* %p) #0 {
+  %b = fptrunc <4 x float> %a to <4 x half>
+  store <4 x half> %b, <4 x half>* %p, align 8
+  ret void
+}
+
+; CHECK-LIBCALL-LABEL: test_vec_fptrunc_double:
+; CHECK-LIBCALL: %call16(__truncdfhf2)
+; CHECK-LIBCALL: %call16(__truncdfhf2)
+; CHECK-LIBCALL: %call16(__truncdfhf2)
+; CHECK-LIBCALL: %call16(__truncdfhf2)
+define void @test_vec_fptrunc_double(<4 x double> %a, <4 x half>* %p) #0 {
+  %b = fptrunc <4 x double> %a to <4 x half>
+  store <4 x half> %b, <4 x half>* %p, align 8
+  ret void
+}
+