Subzero: Refactor x86 register definitions to use the alias mechanism.

unittest/AssemblerX8664/GPRArith.cpp

Index: unittest/AssemblerX8664/GPRArith.cpp
diff --git a/unittest/AssemblerX8664/GPRArith.cpp b/unittest/AssemblerX8664/GPRArith.cpp
index f5404f84118df5746d8b1068903b7a204a36a7af..2333af6bfcdc420d00dc6ace945b1bc513485f04 100644
--- a/unittest/AssemblerX8664/GPRArith.cpp
+++ b/unittest/AssemblerX8664/GPRArith.cpp
@@ -41,7 +41,7 @@ TEST_F(AssemblerX8664Test, SetCC) {
     __ mov(IceType_i32, Encoded_GPR_##Src1(), Immediate(Value1));              \
     __ cmp(IceType_i32, Encoded_GPR_##Src0(), Encoded_GPR_##Src1());           \
     __ mov(IceType_i32, Encoded_GPR_##Dest(), Immediate(0));                   \
-    __ setcc(Cond::Br_##C, RegX8664::getEncodedByteReg(Encoded_GPR_##Dest())); \
+    __ setcc(Cond::Br_##C, RegX8664::getEncodedGPR(Encoded_GPR_##Dest()));     \
     __ setcc(Cond::Br_##C, dwordAddress(T0));                                  \
                                                                                \
     AssembledTest test = assemble();                                           \
@@ -1755,7 +1755,7 @@ TEST_F(AssemblerX8664Test, Bt) {
     __ mov(IceType_i32, Encoded_GPR_##Dst(), Immediate(Value0));               \
     __ mov(IceType_i32, Encoded_GPR_##Src(), Immediate(Value1));               \
     __ bt(Encoded_GPR_##Dst(), Encoded_GPR_##Src());                           \
-    __ setcc(Cond::Br_b, ByteRegister::Encoded_Reg_al);                        \
+    __ setcc(Cond::Br_b, GPRRegister::Encoded_Reg_al);                         \
     __ And(IceType_i32, Encoded_GPR_eax(), Immediate(0xFFu));                  \
                                                                                \
     AssembledTest test = assemble();                                           \