Adding object caching support to MCJIT

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@180146 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 240 insertions, 0 deletions

diff --git a/unittests/ExecutionEngine/MCJIT/MCJITObjectCacheTest.cpp b/unittests/ExecutionEngine/MCJIT/MCJITObjectCacheTest.cpp
new file mode 100644
index 0000000000..0061e30e7a
--- /dev/null
+++ b/unittests/ExecutionEngine/MCJIT/MCJITObjectCacheTest.cpp
@@ -0,0 +1,240 @@
+//===- MCJITObjectCacheTest.cpp - Unit tests for MCJIT object caching -----===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/ADT/OwningPtr.h"
+#include "llvm/ADT/SmallVector.h"
+#include "llvm/ADT/StringMap.h"
+#include "llvm/ADT/StringSet.h"
+#include "llvm/ExecutionEngine/JIT.h"
+#include "llvm/ExecutionEngine/MCJIT.h"
+#include "llvm/ExecutionEngine/ObjectCache.h"
+#include "llvm/ExecutionEngine/SectionMemoryManager.h"
+#include "MCJITTestBase.h"
+#include "gtest/gtest.h"
+
+using namespace llvm;
+
+namespace {
+
+class TestObjectCache : public ObjectCache {
+public:
+  TestObjectCache() : DuplicateInserted(false) { }
+
+  virtual ~TestObjectCache() {
+    // Free any buffers we've allocated.
+    SmallVector<MemoryBuffer *, 2>::iterator it, end;
+    end = AllocatedBuffers.end();
+    for (it = AllocatedBuffers.begin(); it != end; ++it) {
+      delete *it;
+    }
+    AllocatedBuffers.clear();
+  }
+
+  virtual void notifyObjectCompiled(const Module *M, const MemoryBuffer *Obj) {
+    // If we've seen this module before, note that.
+    const std::string ModuleID = M->getModuleIdentifier();
+    if (ObjMap.find(ModuleID) != ObjMap.end())
+      DuplicateInserted = true;
+    // Store a copy of the buffer in our map.
+    ObjMap[ModuleID] = copyBuffer(Obj);
+  }
+
+  // Test-harness-specific functions
+  bool wereDuplicatesInserted() { return DuplicateInserted; }
+
+  bool wasModuleLookedUp(const Module *M) {
+    return ModulesLookedUp.find(M->getModuleIdentifier())
+                                      != ModulesLookedUp.end();
+  }
+
+  const MemoryBuffer* getObjectInternal(const Module* M) {
+    // Look for the module in our map.
+    const std::string ModuleID = M->getModuleIdentifier();
+    StringMap<const MemoryBuffer *>::iterator it = ObjMap.find(ModuleID);
+    if (it == ObjMap.end())
+      return 0;
+    return it->second;
+  }
+
+protected:
+  virtual const MemoryBuffer* getObject(const Module* M) {
+    const MemoryBuffer* BufferFound = getObjectInternal(M);
+    ModulesLookedUp.insert(M->getModuleIdentifier());
+    return BufferFound;
+  }
+
+private:
+  MemoryBuffer *copyBuffer(const MemoryBuffer *Buf) {
+    // Create a local copy of the buffer.
+    MemoryBuffer *NewBuffer = MemoryBuffer::getMemBufferCopy(Buf->getBuffer());
+    AllocatedBuffers.push_back(NewBuffer);
+    return NewBuffer;
+  }
+
+  StringMap<const MemoryBuffer *> ObjMap;
+  StringSet<>                     ModulesLookedUp;
+  SmallVector<MemoryBuffer *, 2>  AllocatedBuffers;
+  bool                            DuplicateInserted;
+};
+
+class MCJITObjectCacheTest : public testing::Test, public MCJITTestBase {
+protected:
+
+  enum {
+    OriginalRC = 6,
+    ReplacementRC = 7
+  };
+
+  virtual void SetUp() {
+    M.reset(createEmptyModule("<main>"));
+    Main = insertMainFunction(M.get(), OriginalRC);
+  }
+
+  void compileAndRun(int ExpectedRC = OriginalRC) {
+    // This function shouldn't be called until after SetUp.
+    ASSERT_TRUE(0 != TheJIT);
+    ASSERT_TRUE(0 != Main);
+
+    TheJIT->finalizeObject();
+    void *vPtr = TheJIT->getPointerToFunction(Main);
+
+    static_cast<SectionMemoryManager*>(MM)->invalidateInstructionCache();
+
+    EXPECT_TRUE(0 != vPtr)
+      << "Unable to get pointer to main() from JIT";
+
+    int (*FuncPtr)(void) = (int(*)(void))(intptr_t)vPtr;
+    int returnCode = FuncPtr();
+    EXPECT_EQ(returnCode, ExpectedRC);
+  }
+
+  Function *Main;
+};
+
+TEST_F(MCJITObjectCacheTest, SetNullObjectCache) {
+  SKIP_UNSUPPORTED_PLATFORM;
+
+  createJIT(M.take());
+
+  TheJIT->setObjectCache(NULL);
+
+  compileAndRun();
+}
+
+
+TEST_F(MCJITObjectCacheTest, VerifyBasicObjectCaching) {
+  SKIP_UNSUPPORTED_PLATFORM;
+
+  OwningPtr<TestObjectCache>  Cache(new TestObjectCache);
+
+  // Save a copy of the module pointer before handing it off to MCJIT.
+  const Module * SavedModulePointer = M.get();
+
+  createJIT(M.take());
+
+  TheJIT->setObjectCache(Cache.get());
+
+  // Verify that our object cache does not contain the module yet.
+  const MemoryBuffer *ObjBuffer = Cache->getObjectInternal(SavedModulePointer);
+  EXPECT_EQ(0, ObjBuffer);
+
+  compileAndRun();
+
+  // Verify that MCJIT tried to look-up this module in the cache.
+  EXPECT_TRUE(Cache->wasModuleLookedUp(SavedModulePointer));
+
+  // Verify that our object cache now contains the module.
+  ObjBuffer = Cache->getObjectInternal(SavedModulePointer);
+  EXPECT_TRUE(0 != ObjBuffer);
+
+  // Verify that the cache was only notified once.
+  EXPECT_FALSE(Cache->wereDuplicatesInserted());
+}
+
+TEST_F(MCJITObjectCacheTest, VerifyLoadFromCache) {
+  SKIP_UNSUPPORTED_PLATFORM;
+
+  OwningPtr<TestObjectCache>  Cache(new TestObjectCache);
+
+  // Compile this module with an MCJIT engine
+  createJIT(M.take());
+  TheJIT->setObjectCache(Cache.get());
+  TheJIT->finalizeObject();
+
+  // Destroy the MCJIT engine we just used
+  TheJIT.reset();
+
+  // Create a new memory manager.
+  MM = new SectionMemoryManager;
+
+  // Create a new module and save it. Use a different return code so we can
+  // tell if MCJIT compiled this module or used the cache.
+  M.reset(createEmptyModule("<main>"));
+  Main = insertMainFunction(M.get(), ReplacementRC);
+  const Module * SecondModulePointer = M.get();
+
+  // Create a new MCJIT instance to load this module then execute it.
+  createJIT(M.take());
+  TheJIT->setObjectCache(Cache.get());
+  compileAndRun();
+
+  // Verify that MCJIT tried to look-up this module in the cache.
+  EXPECT_TRUE(Cache->wasModuleLookedUp(SecondModulePointer));
+
+  // Verify that MCJIT didn't try to cache this again.
+  EXPECT_FALSE(Cache->wereDuplicatesInserted());
+}
+
+TEST_F(MCJITObjectCacheTest, VerifyNonLoadFromCache) {
+  SKIP_UNSUPPORTED_PLATFORM;
+
+  OwningPtr<TestObjectCache>  Cache(new TestObjectCache);
+
+  // Compile this module with an MCJIT engine
+  createJIT(M.take());
+  TheJIT->setObjectCache(Cache.get());
+  TheJIT->finalizeObject();
+
+  // Destroy the MCJIT engine we just used
+  TheJIT.reset();
+
+  // Create a new memory manager.
+  MM = new SectionMemoryManager;
+
+  // Create a new module and save it. Use a different return code so we can
+  // tell if MCJIT compiled this module or used the cache. Note that we use
+  // a new module name here so the module shouldn't be found in the cache.
+  M.reset(createEmptyModule("<not-main>"));
+  Main = insertMainFunction(M.get(), ReplacementRC);
+  const Module * SecondModulePointer = M.get();
+
+  // Create a new MCJIT instance to load this module then execute it.
+  createJIT(M.take());
+  TheJIT->setObjectCache(Cache.get());
+
+  // Verify that our object cache does not contain the module yet.
+  const MemoryBuffer *ObjBuffer = Cache->getObjectInternal(SecondModulePointer);
+  EXPECT_EQ(0, ObjBuffer);
+
+  // Run the function and look for the replacement return code.
+  compileAndRun(ReplacementRC);
+
+  // Verify that MCJIT tried to look-up this module in the cache.
+  EXPECT_TRUE(Cache->wasModuleLookedUp(SecondModulePointer));
+
+  // Verify that our object cache now contains the module.
+  ObjBuffer = Cache->getObjectInternal(SecondModulePointer);
+  EXPECT_TRUE(0 != ObjBuffer);
+
+  // Verify that MCJIT didn't try to cache this again.
+  EXPECT_FALSE(Cache->wereDuplicatesInserted());
+}
+
+} // Namespace
+