Add an option to allocate JITed global data separately from code. By

default, this option is not enabled to support clients who rely on
this behavior.

Fixes http://llvm.org/PR4483

A patch to allocate additional memory for globals after we run out is
forthcoming.

Patch by Reid Kleckner!


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@75059 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Jeffrey Yasskin 2009-07-08 21:59:57 +00:00
parent e41dec60fa
commit 489393d7b9
12 changed files with 291 additions and 72 deletions

View File

@ -267,6 +267,11 @@ public:
return Result;
}
/// allocateGlobal - Allocate memory for a global. Unlike allocateSpace,
/// this method does not allocate memory in the current output buffer,
/// because a global may live longer than the current function.
virtual void *allocateGlobal(uintptr_t Size, unsigned Alignment) = 0;
/// StartMachineBasicBlock - This should be called by the target when a new
/// basic block is about to be emitted. This way the MCE knows where the
/// start of the block is, and can implement getMachineBasicBlockAddress.

View File

@ -87,7 +87,8 @@ protected:
// libraries, the JIT and Interpreter set these functions to ctor pointers
// at startup time if they are linked in.
typedef ExecutionEngine *(*EECtorFn)(ModuleProvider*, std::string*,
CodeGenOpt::Level OptLevel);
CodeGenOpt::Level OptLevel,
bool GVsWithCode);
static EECtorFn JITCtor, InterpCtor;
/// LazyFunctionCreator - If an unknown function is needed, this function
@ -118,8 +119,18 @@ public:
bool ForceInterpreter = false,
std::string *ErrorStr = 0,
CodeGenOpt::Level OptLevel =
CodeGenOpt::Default);
CodeGenOpt::Default,
// Allocating globals with code breaks
// freeMachineCodeForFunction and is probably
// unsafe and bad for performance. However,
// we have clients who depend on this
// behavior, so we must support it.
// Eventually, when we're willing to break
// some backwards compatability, this flag
// should be flipped to false, so that by
// default freeMachineCodeForFunction works.
bool GVsWithCode = true);
/// create - This is the factory method for creating an execution engine which
/// is appropriate for the current machine. This takes ownership of the
/// module.
@ -132,7 +143,8 @@ public:
std::string *ErrorStr = 0,
JITMemoryManager *JMM = 0,
CodeGenOpt::Level OptLevel =
CodeGenOpt::Default);
CodeGenOpt::Default,
bool GVsWithCode = true);
/// addModuleProvider - Add a ModuleProvider to the list of modules that we
/// can JIT from. Note that this takes ownership of the ModuleProvider: when

View File

@ -28,6 +28,7 @@ protected:
bool HasGOT;
bool SizeRequired;
public:
JITMemoryManager() : HasGOT(false), SizeRequired(false) {}
virtual ~JITMemoryManager();
@ -43,6 +44,11 @@ public:
/// start execution, the code pages may need permissions changed.
virtual void setMemoryExecutable(void) = 0;
/// setPoisonMemory - Setting this flag to true makes the memory manager
/// garbage values over freed memory. This is useful for testing and
/// debugging, and is be turned on by default in debug mode.
virtual void setPoisonMemory(bool poison) = 0;
//===--------------------------------------------------------------------===//
// Global Offset Table Management
//===--------------------------------------------------------------------===//
@ -114,7 +120,10 @@ public:
/// allocateSpace - Allocate a memory block of the given size.
virtual uint8_t *allocateSpace(intptr_t Size, unsigned Alignment) = 0;
/// allocateGlobal - Allocate memory for a global.
virtual uint8_t *allocateGlobal(uintptr_t Size, unsigned Alignment) = 0;
/// deallocateMemForFunction - Free JIT memory for the specified function.
/// This is never called when the JIT is currently emitting a function.
virtual void deallocateMemForFunction(const Function *F) = 0;

View File

@ -384,7 +384,8 @@ int ExecutionEngine::runFunctionAsMain(Function *Fn,
ExecutionEngine *ExecutionEngine::create(ModuleProvider *MP,
bool ForceInterpreter,
std::string *ErrorStr,
CodeGenOpt::Level OptLevel) {
CodeGenOpt::Level OptLevel,
bool GVsWithCode) {
ExecutionEngine *EE = 0;
// Make sure we can resolve symbols in the program as well. The zero arg
@ -394,11 +395,11 @@ ExecutionEngine *ExecutionEngine::create(ModuleProvider *MP,
// Unless the interpreter was explicitly selected, try making a JIT.
if (!ForceInterpreter && JITCtor)
EE = JITCtor(MP, ErrorStr, OptLevel);
EE = JITCtor(MP, ErrorStr, OptLevel, GVsWithCode);
// If we can't make a JIT, make an interpreter instead.
if (EE == 0 && InterpCtor)
EE = InterpCtor(MP, ErrorStr, OptLevel);
EE = InterpCtor(MP, ErrorStr, OptLevel, GVsWithCode);
return EE;
}

View File

@ -34,7 +34,8 @@ extern "C" void LLVMLinkInInterpreter() { }
/// create - Create a new interpreter object. This can never fail.
///
ExecutionEngine *Interpreter::create(ModuleProvider *MP, std::string* ErrStr,
CodeGenOpt::Level OptLevel /*unused*/) {
CodeGenOpt::Level OptLevel, /*unused*/
bool GVsWithCode /* unused */) {
// Tell this ModuleProvide to materialize and release the module
if (!MP->materializeModule(ErrStr))
// We got an error, just return 0
@ -98,4 +99,3 @@ Interpreter::runFunction(Function *F,
return ExitValue;
}

View File

@ -108,7 +108,8 @@ public:
/// create - Create an interpreter ExecutionEngine. This can never fail.
///
static ExecutionEngine *create(ModuleProvider *M, std::string *ErrorStr = 0,
CodeGenOpt::Level = CodeGenOpt::Default);
CodeGenOpt::Level = CodeGenOpt::Default,
bool GVsWithCode = true);
/// run - Start execution with the specified function and arguments.
///

View File

@ -197,8 +197,10 @@ void DarwinRegisterFrame(void* FrameBegin) {
ExecutionEngine *ExecutionEngine::createJIT(ModuleProvider *MP,
std::string *ErrorStr,
JITMemoryManager *JMM,
CodeGenOpt::Level OptLevel) {
ExecutionEngine *EE = JIT::createJIT(MP, ErrorStr, JMM, OptLevel);
CodeGenOpt::Level OptLevel,
bool GVsWithCode) {
ExecutionEngine *EE = JIT::createJIT(MP, ErrorStr, JMM, OptLevel,
GVsWithCode);
if (!EE) return 0;
// Make sure we can resolve symbols in the program as well. The zero arg
@ -208,8 +210,8 @@ ExecutionEngine *ExecutionEngine::createJIT(ModuleProvider *MP,
}
JIT::JIT(ModuleProvider *MP, TargetMachine &tm, TargetJITInfo &tji,
JITMemoryManager *JMM, CodeGenOpt::Level OptLevel)
: ExecutionEngine(MP), TM(tm), TJI(tji) {
JITMemoryManager *JMM, CodeGenOpt::Level OptLevel, bool GVsWithCode)
: ExecutionEngine(MP), TM(tm), TJI(tji), AllocateGVsWithCode(GVsWithCode) {
setTargetData(TM.getTargetData());
jitstate = new JITState(MP);
@ -677,37 +679,11 @@ void *JIT::getOrEmitGlobalVariable(const GlobalVariable *GV) {
}
addGlobalMapping(GV, Ptr);
} else {
// GlobalVariable's which are not "constant" will cause trouble in a server
// situation. It's returned in the same block of memory as code which may
// not be writable.
if (isGVCompilationDisabled() && !GV->isConstant()) {
cerr << "Compilation of non-internal GlobalValue is disabled!\n";
abort();
}
// If the global hasn't been emitted to memory yet, allocate space and
// emit it into memory. It goes in the same array as the generated
// code, jump tables, etc.
const Type *GlobalType = GV->getType()->getElementType();
size_t S = getTargetData()->getTypeAllocSize(GlobalType);
size_t A = getTargetData()->getPreferredAlignment(GV);
if (GV->isThreadLocal()) {
MutexGuard locked(lock);
Ptr = TJI.allocateThreadLocalMemory(S);
} else if (TJI.allocateSeparateGVMemory()) {
if (A <= 8) {
Ptr = malloc(S);
} else {
// Allocate S+A bytes of memory, then use an aligned pointer within that
// space.
Ptr = malloc(S+A);
unsigned MisAligned = ((intptr_t)Ptr & (A-1));
Ptr = (char*)Ptr + (MisAligned ? (A-MisAligned) : 0);
}
} else {
Ptr = JCE->allocateSpace(S, A);
}
// emit it into memory.
Ptr = getMemoryForGV(GV);
addGlobalMapping(GV, Ptr);
EmitGlobalVariable(GV);
EmitGlobalVariable(GV); // Initialize the variable.
}
return Ptr;
}
@ -742,14 +718,42 @@ void *JIT::recompileAndRelinkFunction(Function *F) {
/// on the target.
///
char* JIT::getMemoryForGV(const GlobalVariable* GV) {
const Type *ElTy = GV->getType()->getElementType();
size_t GVSize = (size_t)getTargetData()->getTypeAllocSize(ElTy);
char *Ptr;
// GlobalVariable's which are not "constant" will cause trouble in a server
// situation. It's returned in the same block of memory as code which may
// not be writable.
if (isGVCompilationDisabled() && !GV->isConstant()) {
cerr << "Compilation of non-internal GlobalValue is disabled!\n";
abort();
}
// Some applications require globals and code to live together, so they may
// be allocated into the same buffer, but in general globals are allocated
// through the memory manager which puts them near the code but not in the
// same buffer.
const Type *GlobalType = GV->getType()->getElementType();
size_t S = getTargetData()->getTypeAllocSize(GlobalType);
size_t A = getTargetData()->getPreferredAlignment(GV);
if (GV->isThreadLocal()) {
MutexGuard locked(lock);
return TJI.allocateThreadLocalMemory(GVSize);
Ptr = TJI.allocateThreadLocalMemory(S);
} else if (TJI.allocateSeparateGVMemory()) {
if (A <= 8) {
Ptr = (char*)malloc(S);
} else {
// Allocate S+A bytes of memory, then use an aligned pointer within that
// space.
Ptr = (char*)malloc(S+A);
unsigned MisAligned = ((intptr_t)Ptr & (A-1));
Ptr = Ptr + (MisAligned ? (A-MisAligned) : 0);
}
} else if (AllocateGVsWithCode) {
Ptr = (char*)JCE->allocateSpace(S, A);
} else {
return new char[GVSize];
Ptr = (char*)JCE->allocateGlobal(S, A);
}
return Ptr;
}
void JIT::addPendingFunction(Function *F) {

View File

@ -55,10 +55,16 @@ class JIT : public ExecutionEngine {
JITCodeEmitter *JCE; // JCE object
std::vector<JITEventListener*> EventListeners;
/// AllocateGVsWithCode - Some applications require that global variables and
/// code be allocated into the same region of memory, in which case this flag
/// should be set to true. Doing so breaks freeMachineCodeForFunction.
bool AllocateGVsWithCode;
JITState *jitstate;
JIT(ModuleProvider *MP, TargetMachine &tm, TargetJITInfo &tji,
JITMemoryManager *JMM, CodeGenOpt::Level OptLevel);
JIT(ModuleProvider *MP, TargetMachine &tm, TargetJITInfo &tji,
JITMemoryManager *JMM, CodeGenOpt::Level OptLevel,
bool AllocateGVsWithCode);
public:
~JIT();
@ -75,8 +81,9 @@ public:
///
static ExecutionEngine *create(ModuleProvider *MP, std::string *Err,
CodeGenOpt::Level OptLevel =
CodeGenOpt::Default) {
return createJIT(MP, Err, 0, OptLevel);
CodeGenOpt::Default,
bool AllocateGVsWithCode = true) {
return createJIT(MP, Err, 0, OptLevel, AllocateGVsWithCode);
}
virtual void addModuleProvider(ModuleProvider *MP);
@ -151,9 +158,11 @@ public:
/// getCodeEmitter - Return the code emitter this JIT is emitting into.
JITCodeEmitter *getCodeEmitter() const { return JCE; }
static ExecutionEngine *createJIT(ModuleProvider *MP, std::string *Err,
static ExecutionEngine *createJIT(ModuleProvider *MP,
std::string *Err,
JITMemoryManager *JMM,
CodeGenOpt::Level OptLevel);
CodeGenOpt::Level OptLevel,
bool AllocateGVsWithCode);
// Run the JIT on F and return information about the generated code

View File

@ -527,6 +527,11 @@ namespace {
/// allocate a new one of the given size.
virtual void *allocateSpace(uintptr_t Size, unsigned Alignment);
/// allocateGlobal - Allocate memory for a global. Unlike allocateSpace,
/// this method does not allocate memory in the current output buffer,
/// because a global may live longer than the current function.
virtual void *allocateGlobal(uintptr_t Size, unsigned Alignment);
virtual void addRelocation(const MachineRelocation &MR) {
Relocations.push_back(MR);
}
@ -1161,6 +1166,11 @@ void* JITEmitter::allocateSpace(uintptr_t Size, unsigned Alignment) {
return CurBufferPtr;
}
void* JITEmitter::allocateGlobal(uintptr_t Size, unsigned Alignment) {
// Delegate this call through the memory manager.
return MemMgr->allocateGlobal(Size, Alignment);
}
void JITEmitter::emitConstantPool(MachineConstantPool *MCP) {
if (TheJIT->getJITInfo().hasCustomConstantPool())
return;

View File

@ -251,6 +251,8 @@ namespace {
/// middle of emitting a function, and we don't know how large the function we
/// are emitting is.
class VISIBILITY_HIDDEN DefaultJITMemoryManager : public JITMemoryManager {
bool PoisonMemory; // Whether to poison freed memory.
std::vector<sys::MemoryBlock> Blocks; // Memory blocks allocated by the JIT
FreeRangeHeader *FreeMemoryList; // Circular list of free blocks.
@ -258,6 +260,7 @@ namespace {
MemoryRangeHeader *CurBlock;
uint8_t *CurStubPtr, *StubBase;
uint8_t *CurGlobalPtr, *GlobalEnd;
uint8_t *GOTBase; // Target Specific reserved memory
void *DlsymTable; // Stub external symbol information
@ -324,7 +327,7 @@ namespace {
CurBlock = FreeMemoryList;
FreeMemoryList = FreeMemoryList->AllocateBlock();
uint8_t *result = (uint8_t *)CurBlock+1;
uint8_t *result = (uint8_t *)(CurBlock + 1);
if (Alignment == 0) Alignment = 1;
result = (uint8_t*)(((intptr_t)result+Alignment-1) &
@ -336,6 +339,30 @@ namespace {
return result;
}
/// allocateGlobal - Allocate memory for a global. Unlike allocateSpace,
/// this method does not touch the current block and can be called at any
/// time.
uint8_t *allocateGlobal(uintptr_t Size, unsigned Alignment) {
uint8_t *Result = CurGlobalPtr;
// Align the pointer.
if (Alignment == 0) Alignment = 1;
Result = (uint8_t*)(((uintptr_t)Result + Alignment-1) &
~(uintptr_t)(Alignment-1));
// Move the current global pointer forward.
CurGlobalPtr += Result - CurGlobalPtr + Size;
// Check for overflow.
if (CurGlobalPtr > GlobalEnd) {
// FIXME: Allocate more memory.
fprintf(stderr, "JIT ran out of memory for globals!\n");
abort();
}
return Result;
}
/// startExceptionTable - Use startFunctionBody to allocate memory for the
/// function's exception table.
uint8_t* startExceptionTable(const Function* F, uintptr_t &ActualSize) {
@ -375,12 +402,12 @@ namespace {
// Find the block that is allocated for this function.
MemoryRangeHeader *MemRange = I->second;
assert(MemRange->ThisAllocated && "Block isn't allocated!");
// Fill the buffer with garbage!
#ifndef NDEBUG
memset(MemRange+1, 0xCD, MemRange->BlockSize-sizeof(*MemRange));
#endif
if (PoisonMemory) {
memset(MemRange+1, 0xCD, MemRange->BlockSize-sizeof(*MemRange));
}
// Free the memory.
FreeMemoryList = MemRange->FreeBlock(FreeMemoryList);
@ -393,12 +420,12 @@ namespace {
// Find the block that is allocated for this function.
MemRange = I->second;
assert(MemRange->ThisAllocated && "Block isn't allocated!");
// Fill the buffer with garbage!
#ifndef NDEBUG
memset(MemRange+1, 0xCD, MemRange->BlockSize-sizeof(*MemRange));
#endif
if (PoisonMemory) {
memset(MemRange+1, 0xCD, MemRange->BlockSize-sizeof(*MemRange));
}
// Free the memory.
FreeMemoryList = MemRange->FreeBlock(FreeMemoryList);
@ -420,10 +447,22 @@ namespace {
for (unsigned i = 0, e = Blocks.size(); i != e; ++i)
sys::Memory::setExecutable(Blocks[i]);
}
/// setPoisonMemory - Controls whether we write garbage over freed memory.
///
void setPoisonMemory(bool poison) {
PoisonMemory = poison;
}
};
}
DefaultJITMemoryManager::DefaultJITMemoryManager() {
#ifdef NDEBUG
PoisonMemory = true;
#else
PoisonMemory = false;
#endif
// Allocate a 16M block of memory for functions.
#if defined(__APPLE__) && defined(__arm__)
sys::MemoryBlock MemBlock = getNewMemoryBlock(4 << 20);
@ -433,11 +472,13 @@ DefaultJITMemoryManager::DefaultJITMemoryManager() {
uint8_t *MemBase = static_cast<uint8_t*>(MemBlock.base());
// Allocate stubs backwards from the base, allocate functions forward
// from the base.
// Allocate stubs backwards to the base, globals forward from the stubs, and
// functions forward after globals.
StubBase = MemBase;
CurStubPtr = MemBase + 512*1024; // Use 512k for stubs, working backwards.
CurGlobalPtr = CurStubPtr; // Use 2M for globals, working forwards.
GlobalEnd = CurGlobalPtr + 2*1024*1024;
// We set up the memory chunk with 4 mem regions, like this:
// [ START
// [ Free #0 ] -> Large space to allocate functions from.
@ -474,7 +515,7 @@ DefaultJITMemoryManager::DefaultJITMemoryManager() {
// Add a FreeRangeHeader to the start of the function body region, indicating
// that the space is free. Mark the previous block allocated so we never look
// at it.
FreeRangeHeader *Mem0 = (FreeRangeHeader*)CurStubPtr;
FreeRangeHeader *Mem0 = (FreeRangeHeader*)GlobalEnd;
Mem0->ThisAllocated = 0;
Mem0->PrevAllocated = 1;
Mem0->BlockSize = (char*)Mem1-(char*)Mem0;
@ -522,7 +563,7 @@ uint8_t *DefaultJITMemoryManager::allocateStub(const GlobalValue* F,
sys::MemoryBlock DefaultJITMemoryManager::getNewMemoryBlock(unsigned size) {
// Allocate a new block close to the last one.
const sys::MemoryBlock *BOld = Blocks.empty() ? 0 : &Blocks.front();
const sys::MemoryBlock *BOld = Blocks.empty() ? 0 : &Blocks.back();
std::string ErrMsg;
sys::MemoryBlock B = sys::Memory::AllocateRWX(size, BOld, &ErrMsg);
if (B.base() == 0) {

View File

@ -43,7 +43,8 @@ MAttrs("mattr",
///
ExecutionEngine *JIT::createJIT(ModuleProvider *MP, std::string *ErrorStr,
JITMemoryManager *JMM,
CodeGenOpt::Level OptLevel) {
CodeGenOpt::Level OptLevel,
bool AllocateGVsWithCode) {
const TargetMachineRegistry::entry *TheArch = MArch;
if (TheArch == 0) {
std::string Error;
@ -75,7 +76,7 @@ ExecutionEngine *JIT::createJIT(ModuleProvider *MP, std::string *ErrorStr,
// If the target supports JIT code generation, return a new JIT now.
if (TargetJITInfo *TJ = Target->getJITInfo())
return new JIT(MP, *Target, *TJ, JMM, OptLevel);
return new JIT(MP, *Target, *TJ, JMM, OptLevel, AllocateGVsWithCode);
if (ErrorStr)
*ErrorStr = "target does not support JIT code generation";

View File

@ -0,0 +1,126 @@
//===- JITEmitter.cpp - Unit tests for the JIT code emitter ---------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#include "gtest/gtest.h"
#include "llvm/ADT/OwningPtr.h"
#include "llvm/BasicBlock.h"
#include "llvm/Constant.h"
#include "llvm/Constants.h"
#include "llvm/DerivedTypes.h"
#include "llvm/ExecutionEngine/JIT.h"
#include "llvm/ExecutionEngine/JITMemoryManager.h"
#include "llvm/Function.h"
#include "llvm/GlobalValue.h"
#include "llvm/GlobalVariable.h"
#include "llvm/Module.h"
#include "llvm/ModuleProvider.h"
#include "llvm/Support/IRBuilder.h"
#include "llvm/Target/TargetSelect.h"
#include "llvm/Type.h"
using namespace llvm;
namespace {
Function *makeReturnGlobal(std::string Name, GlobalVariable *G, Module *M) {
std::vector<const Type*> params;
const FunctionType *FTy = FunctionType::get(Type::VoidTy, params, false);
Function *F = Function::Create(FTy, GlobalValue::ExternalLinkage, Name, M);
BasicBlock *Entry = BasicBlock::Create("entry", F);
IRBuilder<> builder(Entry);
Value *Load = builder.CreateLoad(G);
const Type *GTy = G->getType()->getElementType();
Value *Add = builder.CreateAdd(Load, ConstantInt::get(GTy, 1LL));
builder.CreateStore(Add, G);
builder.CreateRet(Add);
return F;
}
// Regression test for a bug. The JIT used to allocate globals inside the same
// memory block used for the function, and when the function code was freed,
// the global was left in the same place. This test allocates a function
// that uses and global, deallocates it, and then makes sure that the global
// stays alive after that.
TEST(JIT, GlobalInFunction) {
LLVMContext context;
Module *M = new Module("<main>", context);
ExistingModuleProvider *MP = new ExistingModuleProvider(M);
JITMemoryManager *MemMgr = JITMemoryManager::CreateDefaultMemManager();
// Tell the memory manager to poison freed memory so that accessing freed
// memory is more easily tested.
MemMgr->setPoisonMemory(true);
std::string Error;
OwningPtr<ExecutionEngine> JIT(ExecutionEngine::createJIT(
MP,
&Error,
MemMgr,
CodeGenOpt::Default,
false)); // This last argument enables the fix.
ASSERT_EQ(Error, "");
// Create a global variable.
const Type *GTy = Type::Int32Ty;
GlobalVariable *G = new GlobalVariable(
*M,
GTy,
false, // Not constant.
GlobalValue::InternalLinkage,
Constant::getNullValue(GTy),
"myglobal");
// Make a function that points to a global.
Function *F1 = makeReturnGlobal("F1", G, M);
// Get the pointer to the native code to force it to JIT the function and
// allocate space for the global.
void (*F1Ptr)();
// Hack to avoid ISO C++ warning about casting function pointers.
*(void**)(void*)&F1Ptr = JIT->getPointerToFunction(F1);
// Since F1 was codegen'd, a pointer to G should be available.
int32_t *GPtr = (int32_t*)JIT->getPointerToGlobalIfAvailable(G);
ASSERT_NE((int32_t*)NULL, GPtr);
EXPECT_EQ(0, *GPtr);
// F1() should increment G.
F1Ptr();
EXPECT_EQ(1, *GPtr);
// Make a second function identical to the first, referring to the same
// global.
Function *F2 = makeReturnGlobal("F2", G, M);
// Hack to avoid ISO C++ warning about casting function pointers.
void (*F2Ptr)();
*(void**)(void*)&F2Ptr = JIT->getPointerToFunction(F2);
// F2() should increment G.
F2Ptr();
EXPECT_EQ(2, *GPtr);
// Deallocate F1.
JIT->freeMachineCodeForFunction(F1);
// F2() should *still* increment G.
F2Ptr();
EXPECT_EQ(3, *GPtr);
}
// TODO(rnk): This seems to only run once for both tests, which is unexpected.
// That works just fine, but we shouldn't duplicate the code.
class JITEnvironment : public testing::Environment {
virtual void SetUp() {
// Required for ExecutionEngine::createJIT to create a JIT.
InitializeNativeTarget();
}
};
testing::Environment* const jit_env =
testing::AddGlobalTestEnvironment(new JITEnvironment);
}