Index: lib/Target/AMDGPU/SIISelLowering.cpp
===================================================================
--- lib/Target/AMDGPU/SIISelLowering.cpp
+++ lib/Target/AMDGPU/SIISelLowering.cpp
@@ -700,9 +700,12 @@
   if (CC != CallingConv::AMDGPU_KERNEL && VT.isVector()) {
     EVT ScalarVT = VT.getScalarType();
     unsigned Size = ScalarVT.getSizeInBits();
-    if (Size == 32 || Size == 64)
+    if (Size == 32)
       return ScalarVT.getSimpleVT();
 
+    if (Size == 64)
+      return MVT::i32;
+
     if (Size == 16 &&
         Subtarget->has16BitInsts() &&
         isPowerOf2_32(VT.getVectorNumElements()))
@@ -720,9 +723,12 @@
     EVT ScalarVT = VT.getScalarType();
     unsigned Size = ScalarVT.getSizeInBits();
 
-    if (Size == 32 || Size == 64)
+    if (Size == 32)
       return NumElts;
 
+    if (Size == 64)
+      return 2 * NumElts;
+
     // FIXME: Fails to break down as we want with v3.
     if (Size == 16 && Subtarget->has16BitInsts() && isPowerOf2_32(NumElts))
       return VT.getVectorNumElements() / 2;
@@ -739,13 +745,20 @@
     unsigned NumElts = VT.getVectorNumElements();
     EVT ScalarVT = VT.getScalarType();
     unsigned Size = ScalarVT.getSizeInBits();
-    if (Size == 32 || Size == 64) {
+    if (Size == 32) {
       RegisterVT = ScalarVT.getSimpleVT();
       IntermediateVT = RegisterVT;
       NumIntermediates = NumElts;
       return NumIntermediates;
     }
 
+    if (Size == 64) {
+      RegisterVT = MVT::i32;
+      IntermediateVT = RegisterVT;
+      NumIntermediates = 2 * NumElts;
+      return NumIntermediates;
+    }
+
     // FIXME: We should fix the ABI to be the same on targets without 16-bit
     // support, but unless we can properly handle 3-vectors, it will be still be
     // inconsistent.
Index: test/CodeGen/AMDGPU/call-argument-types.ll
===================================================================
--- test/CodeGen/AMDGPU/call-argument-types.ll
+++ test/CodeGen/AMDGPU/call-argument-types.ll
@@ -25,6 +25,8 @@
 declare void @external_void_func_f32(float) #0
 declare void @external_void_func_f64(double) #0
 declare void @external_void_func_v2f32(<2 x float>) #0
+declare void @external_void_func_v2f64(<2 x double>) #0
+declare void @external_void_func_v3f64(<3 x double>) #0
 
 declare void @external_void_func_v2i16(<2 x i16>) #0
 declare void @external_void_func_v2f16(<2 x half>) #0
@@ -274,10 +276,21 @@
   ret void
 }
 
+; GCN-LABEL: {{^}}test_call_external_void_func_v2i64_imm:
+; GCN-DAG: v_mov_b32_e32 v0, 1
+; GCN-DAG: v_mov_b32_e32 v1, 2
+; GCN-DAG: v_mov_b32_e32 v2, 3
+; GCN-DAG: v_mov_b32_e32 v3, 4
+; GCN: s_swappc_b64
+define amdgpu_kernel void @test_call_external_void_func_v2i64_imm() #0 {
+  call void @external_void_func_v2i64(<2 x i64> <i64 8589934593, i64 17179869187>)
+  ret void
+}
+
 ; GCN-LABEL: {{^}}test_call_external_void_func_v3i64:
 ; GCN: buffer_load_dwordx4 v[0:3]
-; GCN: v_mov_b32_e32 v4, s
-; GCN: v_mov_b32_e32 v5, s
+; GCN: v_mov_b32_e32 v4, 1
+; GCN: v_mov_b32_e32 v5, 2
 ; GCN: s_waitcnt
 ; GCN-NEXT: s_swappc_b64
 define amdgpu_kernel void @test_call_external_void_func_v3i64() #0 {
@@ -288,13 +301,12 @@
   ret void
 }
 
-; FIXME: Immedites should fold directly into v_mov_b32s
 ; GCN-LABEL: {{^}}test_call_external_void_func_v4i64:
 ; GCN: buffer_load_dwordx4 v[0:3]
-; GCN-DAG: v_mov_b32_e32 v4, s
-; GCN-DAG: v_mov_b32_e32 v5, s
-; GCN-DAG: v_mov_b32_e32 v6, s
-; GCN-DAG: v_mov_b32_e32 v7, s
+; GCN-DAG: v_mov_b32_e32 v4, 1
+; GCN-DAG: v_mov_b32_e32 v5, 2
+; GCN-DAG: v_mov_b32_e32 v6, 3
+; GCN-DAG: v_mov_b32_e32 v7, 4
 
 ; GCN: s_waitcnt
 ; GCN-NEXT: s_swappc_b64
@@ -342,6 +354,30 @@
   ret void
 }
 
+; GCN-LABEL: {{^}}test_call_external_void_func_v2f64_imm:
+; GCN: v_mov_b32_e32 v0, 0{{$}}
+; GCN: v_mov_b32_e32 v1, 2.0
+; GCN: v_mov_b32_e32 v2, 0{{$}}
+; GCN: v_mov_b32_e32 v3, 0x40100000
+; GCN: s_swappc_b64
+define amdgpu_kernel void @test_call_external_void_func_v2f64_imm() #0 {
+  call void @external_void_func_v2f64(<2 x double> <double 2.0, double 4.0>)
+  ret void
+}
+
+; GCN-LABEL: {{^}}test_call_external_void_func_v3f64_imm:
+; GCN-DAG: v_mov_b32_e32 v0, 0{{$}}
+; GCN-DAG: v_mov_b32_e32 v1, 2.0
+; GCN-DAG: v_mov_b32_e32 v2, 0{{$}}
+; GCN-DAG: v_mov_b32_e32 v3, 0x40100000
+; GCN-DAG: v_mov_b32_e32 v4, 0{{$}}
+; GCN-DAG: v_mov_b32_e32 v5, 0x40200000
+; GCN-DAG: s_swappc_b64
+define amdgpu_kernel void @test_call_external_void_func_v3f64_imm() #0 {
+  call void @external_void_func_v3f64(<3 x double> <double 2.0, double 4.0, double 8.0>)
+  ret void
+}
+
 ; GCN-LABEL: {{^}}test_call_external_void_func_v2i16:
 ; GFX9: buffer_load_dword v0
 ; GFX9-NOT: v0