Index: lib/Target/AMDGPU/SIRegisterInfo.td
===================================================================
--- lib/Target/AMDGPU/SIRegisterInfo.td
+++ lib/Target/AMDGPU/SIRegisterInfo.td
@@ -253,37 +253,49 @@
 def SReg_32 : RegisterClass<"AMDGPU", [i32, f32], 32,
   (add SGPR_32, M0, VCC_LO, VCC_HI, EXEC_LO, EXEC_HI, FLAT_SCR_LO, FLAT_SCR_HI,
    TTMP_32, TMA_LO, TMA_HI, TBA_LO, TBA_HI)
->;
+> {
+  let AllocationPriority = 1;
+}
 
-def SGPR_64 : RegisterClass<"AMDGPU", [v2i32, i64, f64], 32, (add SGPR_64Regs)>;
+def SGPR_64 : RegisterClass<"AMDGPU", [v2i32, i64, f64], 32, (add SGPR_64Regs)>
+{
+  let AllocationPriority = 2;
+}
 
 def TTMP_64 : RegisterClass<"AMDGPU", [v2i32, i64, f64], 32, (add TTMP_64Regs)> {
   let isAllocatable = 0;
+  let AllocationPriority = 2;
 }
 
 def SReg_64 : RegisterClass<"AMDGPU", [v2i32, i64, f64, i1], 32,
   (add SGPR_64, VCC, EXEC, FLAT_SCR, TTMP_64, TBA, TMA)
->;
+> {
+  let AllocationPriority = 2;
+}
 
 def SReg_128 : RegisterClass<"AMDGPU", [v4i32, v16i8, v2i64], 32, (add SGPR_128)> {
   // Requires 2 s_mov_b64 to copy
   let CopyCost = 2;
+  let AllocationPriority = 4;
 }
 
 def SReg_256 : RegisterClass<"AMDGPU", [v8i32, v8f32], 32, (add SGPR_256)> {
   // Requires 4 s_mov_b64 to copy
   let CopyCost = 4;
+  let AllocationPriority = 5;
 }
 
 def SReg_512 : RegisterClass<"AMDGPU", [v64i8, v16i32], 32, (add SGPR_512)> {
   // Requires 8 s_mov_b64 to copy
   let CopyCost = 8;
+  let AllocationPriority = 6;
 }
 
 // Register class for all vector registers (VGPRs + Interploation Registers)
 def VReg_64 : RegisterClass<"AMDGPU", [i64, f64, v2i32, v2f32], 32, (add VGPR_64)> {
   // Requires 2 v_mov_b32 to copy
   let CopyCost = 2;
+  let AllocationPriority = 2;
 }
 
 def VReg_96 : RegisterClass<"AMDGPU", [untyped], 32, (add VGPR_96)> {
@@ -291,19 +303,23 @@
 
   // Requires 3 v_mov_b32 to copy
   let CopyCost = 3;
+  let AllocationPriority = 3;
 }
 
 def VReg_128 : RegisterClass<"AMDGPU", [v4i32, v4f32, v2i64, v2f64], 32, (add VGPR_128)> {
   // Requires 4 v_mov_b32 to copy
   let CopyCost = 4;
+  let AllocationPriority = 4;
 }
 
 def VReg_256 : RegisterClass<"AMDGPU", [v8i32, v8f32], 32, (add VGPR_256)> {
   let CopyCost = 8;
+  let AllocationPriority = 5;
 }
 
 def VReg_512 : RegisterClass<"AMDGPU", [v16i32, v16f32], 32, (add VGPR_512)> {
   let CopyCost = 16;
+  let AllocationPriority = 6;
 }
 
 def VReg_1 : RegisterClass<"AMDGPU", [i1], 32, (add VGPR_32)> {