Index: llvm/unittests/tools/llvm-exegesis/Mips/BenchmarkResultTest.cpp
===================================================================
--- llvm/unittests/tools/llvm-exegesis/Mips/BenchmarkResultTest.cpp
+++ llvm/unittests/tools/llvm-exegesis/Mips/BenchmarkResultTest.cpp
@@ -8,6 +8,7 @@
 
 #include "BenchmarkResult.h"
 #include "MipsInstrInfo.h"
+#include "TestBase.h"
 #include "llvm/ADT/SmallString.h"
 #include "llvm/Support/Error.h"
 #include "llvm/Support/Path.h"
@@ -27,8 +28,6 @@
 namespace llvm {
 namespace exegesis {
 
-void InitializeMipsExegesisTarget();
-
 bool operator==(const BenchmarkMeasure &A, const BenchmarkMeasure &B) {
   return std::tie(A.Key, A.PerInstructionValue, A.PerSnippetValue) ==
          std::tie(B.Key, B.PerInstructionValue, B.PerSnippetValue);
@@ -53,15 +52,10 @@
 
 namespace {
 
-TEST(BenchmarkResultTest, WriteToAndReadFromDisk) {
-  LLVMInitializeMipsTargetInfo();
-  LLVMInitializeMipsTarget();
-  LLVMInitializeMipsTargetMC();
-  InitializeMipsExegesisTarget();
+class BenchmarkResultTest : public MipsTestBase {};
 
+TEST_F(BenchmarkResultTest, WriteToAndReadFromDisk) {
   // Read benchmarks.
-  const LLVMState State("mips-unknown-linux", "mips32");
-
   ExitOnError ExitOnErr;
 
   InstructionBenchmark ToDisk;
@@ -126,7 +120,7 @@
   }
 }
 
-TEST(BenchmarkResultTest, PerInstructionStats) {
+TEST_F(BenchmarkResultTest, PerInstructionStats) {
   PerInstructionStats Stats;
   Stats.push(BenchmarkMeasure{"a", 0.5, 0.0});
   Stats.push(BenchmarkMeasure{"a", 1.5, 0.0});
Index: llvm/unittests/tools/llvm-exegesis/Mips/CMakeLists.txt
===================================================================
--- llvm/unittests/tools/llvm-exegesis/Mips/CMakeLists.txt
+++ llvm/unittests/tools/llvm-exegesis/Mips/CMakeLists.txt
@@ -15,6 +15,7 @@
 
 add_llvm_unittest(LLVMExegesisMipsTests
   BenchmarkResultTest.cpp
+  RegisterAliasingTest.cpp
   SnippetGeneratorTest.cpp
   TargetTest.cpp
   )
Index: llvm/unittests/tools/llvm-exegesis/Mips/SnippetGeneratorTest.cpp
===================================================================
--- llvm/unittests/tools/llvm-exegesis/Mips/SnippetGeneratorTest.cpp
+++ llvm/unittests/tools/llvm-exegesis/Mips/SnippetGeneratorTest.cpp
@@ -10,16 +10,14 @@
 #include "Latency.h"
 #include "LlvmState.h"
 #include "MCInstrDescView.h"
-#include "RegisterAliasing.h"
 #include "MipsInstrInfo.h"
+#include "RegisterAliasing.h"
+#include "TestBase.h"
 
 #include <unordered_set>
 
 namespace llvm {
 namespace exegesis {
-
-void InitializeMipsExegesisTarget();
-
 namespace {
 
 using testing::AnyOf;
@@ -29,21 +27,7 @@
 MATCHER(IsInvalid, "") { return !arg.isValid(); }
 MATCHER(IsReg, "") { return arg.isReg(); }
 
-class MipsSnippetGeneratorTest : public ::testing::Test {
-protected:
-  MipsSnippetGeneratorTest() : State("mips-unknown-linux", "mips32"),
-	InstrInfo(State.getInstrInfo()) {}
-
-  static void SetUpTestCase() {
-    LLVMInitializeMipsTargetInfo();
-    LLVMInitializeMipsTarget();
-    LLVMInitializeMipsTargetMC();
-    InitializeMipsExegesisTarget();
-  }
-
-  LLVMState State;
-  const MCInstrInfo &InstrInfo;
-};
+class MipsSnippetGeneratorTest : public MipsTestBase {};
 
 template <typename SnippetGeneratorT>
 class SnippetGeneratorTest : public MipsSnippetGeneratorTest {
Index: llvm/unittests/tools/llvm-exegesis/Mips/TargetTest.cpp
===================================================================
--- llvm/unittests/tools/llvm-exegesis/Mips/TargetTest.cpp
+++ llvm/unittests/tools/llvm-exegesis/Mips/TargetTest.cpp
@@ -12,6 +12,7 @@
 #include <memory>
 
 #include "MCTargetDesc/MipsMCTargetDesc.h"
+#include "TestBase.h"
 #include "llvm/Support/TargetRegistry.h"
 #include "llvm/Support/TargetSelect.h"
 #include "gmock/gmock.h"
@@ -19,9 +20,6 @@
 
 namespace llvm {
 namespace exegesis {
-
-void InitializeMipsExegesisTarget();
-
 namespace {
 
 using testing::AllOf;
@@ -49,25 +47,12 @@
                ElementsAre(IsReg(Reg), IsReg(Mips::ZERO), IsImm(Value)));
 }
 
-constexpr const char kTriple[] = "mips-unknown-linux";
-
-class MipsTargetTest : public ::testing::Test {
+class MipsTargetTest : public MipsTestBase {
 protected:
-  MipsTargetTest() : State(kTriple, "mips32", "") {}
-
-  static void SetUpTestCase() {
-    LLVMInitializeMipsTargetInfo();
-    LLVMInitializeMipsTarget();
-    LLVMInitializeMipsTargetMC();
-    InitializeMipsExegesisTarget();
-  }
-
   std::vector<MCInst> setRegTo(unsigned Reg, const APInt &Value) {
     return State.getExegesisTarget().setRegTo(State.getSubtargetInfo(), Reg,
                                               Value);
   }
-
-  LLVMState State;
 };
 
 TEST_F(MipsTargetTest, SetRegToConstant) {
Index: llvm/unittests/tools/llvm-exegesis/Mips/TestBase.h
===================================================================
--- /dev/null
+++ llvm/unittests/tools/llvm-exegesis/Mips/TestBase.h
@@ -0,0 +1,42 @@
+//===-- TestBase.h ----------------------------------------------*- C++ -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+// Test fixture common to all Mips tests.
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_UNITTESTS_TOOLS_LLVMEXEGESIS_MIPS_TESTBASE_H
+#define LLVM_UNITTESTS_TOOLS_LLVMEXEGESIS_MIPS_TESTBASE_H
+
+#include "LlvmState.h"
+#include "llvm/Support/TargetRegistry.h"
+#include "llvm/Support/TargetSelect.h"
+#include "gmock/gmock.h"
+#include "gtest/gtest.h"
+
+namespace llvm {
+namespace exegesis {
+
+void InitializeMipsExegesisTarget();
+
+class MipsTestBase : public ::testing::Test {
+protected:
+  MipsTestBase() : State("mips-unknown-linux", "mips32") {}
+
+  static void SetUpTestCase() {
+    LLVMInitializeMipsTargetInfo();
+    LLVMInitializeMipsTargetMC();
+    LLVMInitializeMipsTarget();
+    InitializeMipsExegesisTarget();
+  }
+
+  const LLVMState State;
+};
+
+} // namespace exegesis
+} // namespace llvm
+
+#endif