[Mips][llvm-exegesis] Add a Mips target

The target does just enough to be able to run llvm-exegesis in latency
mode for at least some opcodes.

Patch by Miloš Stojanović.

Differential Revision: https://reviews.llvm.org/D68649

llvm-svn: 374590

3 files changed, 115 insertions, 0 deletions

diff --git a/llvm/unittests/tools/llvm-exegesis/CMakeLists.txt b/llvm/unittests/tools/llvm-exegesis/CMakeLists.txt
index 05b2b3bc605..d6d2a2d743c 100644
--- a/llvm/unittests/tools/llvm-exegesis/CMakeLists.txt
+++ b/llvm/unittests/tools/llvm-exegesis/CMakeLists.txt
@@ -30,3 +30,6 @@ endif()
 if(LLVM_TARGETS_TO_BUILD MATCHES "PowerPC")
   add_subdirectory(PowerPC)
 endif()
+if(LLVM_TARGETS_TO_BUILD MATCHES "Mips")
+  add_subdirectory(Mips)
+endif()
diff --git a/llvm/unittests/tools/llvm-exegesis/Mips/CMakeLists.txt b/llvm/unittests/tools/llvm-exegesis/Mips/CMakeLists.txt
new file mode 100644
index 00000000000..d6955d34706
--- /dev/null
+++ b/llvm/unittests/tools/llvm-exegesis/Mips/CMakeLists.txt
@@ -0,0 +1,21 @@
+include_directories(
+  ${LLVM_MAIN_SRC_DIR}/lib/Target/Mips
+  ${LLVM_BINARY_DIR}/lib/Target/Mips
+  ${LLVM_MAIN_SRC_DIR}/tools/llvm-exegesis/lib
+  )
+
+set(LLVM_LINK_COMPONENTS
+  MC
+  MCParser
+  Object
+  Support
+  Symbolize
+  Mips
+  )
+
+add_llvm_unittest(LLVMExegesisMipsTests
+  TargetTest.cpp
+  )
+target_link_libraries(LLVMExegesisMipsTests PRIVATE
+  LLVMExegesis
+  LLVMExegesisMips)
diff --git a/llvm/unittests/tools/llvm-exegesis/Mips/TargetTest.cpp b/llvm/unittests/tools/llvm-exegesis/Mips/TargetTest.cpp
new file mode 100644
index 00000000000..16c8e5fda27
--- /dev/null
+++ b/llvm/unittests/tools/llvm-exegesis/Mips/TargetTest.cpp
@@ -0,0 +1,91 @@
+//===-- TargetTest.cpp ------------------------------------------*- 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
+//
+//===----------------------------------------------------------------------===//
+
+#include "Target.h"
+
+#include <cassert>
+#include <memory>
+
+#include "MCTargetDesc/MipsMCTargetDesc.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();
+
+namespace {
+
+using testing::AllOf;
+using testing::ElementsAre;
+using testing::Eq;
+using testing::Matcher;
+using testing::Property;
+
+Matcher<MCOperand> IsImm(int64_t Value) {
+  return AllOf(Property(&MCOperand::isImm, Eq(true)),
+               Property(&MCOperand::getImm, Eq(Value)));
+}
+
+Matcher<MCOperand> IsReg(unsigned Reg) {
+  return AllOf(Property(&MCOperand::isReg, Eq(true)),
+               Property(&MCOperand::getReg, Eq(Reg)));
+}
+
+Matcher<MCInst> OpcodeIs(unsigned Opcode) {
+  return Property(&MCInst::getOpcode, Eq(Opcode));
+}
+
+Matcher<MCInst> IsLoadLowImm(int64_t Reg, int64_t Value) {
+  return AllOf(OpcodeIs(Mips::ORi),
+               ElementsAre(IsReg(Reg), IsReg(Mips::ZERO), IsImm(Value)));
+}
+
+constexpr const char kTriple[] = "mips-unknown-linux";
+
+class MipsTargetTest : public ::testing::Test {
+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) {
+  const uint16_t Value = 0xFFFFU;
+  const unsigned Reg = Mips::T0;
+  EXPECT_THAT(setRegTo(Reg, APInt(16, Value)),
+              ElementsAre(IsLoadLowImm(Reg, Value)));
+}
+
+TEST_F(MipsTargetTest, DefaultPfmCounters) {
+  const std::string Expected = "CYCLES";
+  EXPECT_EQ(State.getExegesisTarget().getPfmCounters("").CycleCounter,
+            Expected);
+  EXPECT_EQ(
+      State.getExegesisTarget().getPfmCounters("unknown_cpu").CycleCounter,
+      Expected);
+}
+
+} // namespace
+} // namespace exegesis
+} // namespace llvm