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HookedByTheJit.cpp
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/*******************************************************************************
* Copyright IBM Corp. and others 2000
*
* This program and the accompanying materials are made available under
* the terms of the Eclipse Public License 2.0 which accompanies this
* distribution and is available at https://www.eclipse.org/legal/epl-2.0/
* or the Apache License, Version 2.0 which accompanies this distribution and
* is available at https://www.apache.org/licenses/LICENSE-2.0.
*
* This Source Code may also be made available under the following
* Secondary Licenses when the conditions for such availability set
* forth in the Eclipse Public License, v. 2.0 are satisfied: GNU
* General Public License, version 2 with the GNU Classpath
* Exception [1] and GNU General Public License, version 2 with the
* OpenJDK Assembly Exception [2].
*
* [1] https://www.gnu.org/software/classpath/license.html
* [2] https://openjdk.org/legal/assembly-exception.html
*
* SPDX-License-Identifier: EPL-2.0 OR Apache-2.0 OR GPL-2.0-only WITH Classpath-exception-2.0 OR GPL-2.0-only WITH OpenJDK-assembly-exception-1.0
*******************************************************************************/
#include <algorithm>
#include <limits.h>
#if defined(J9VM_OPT_JITSERVER)
#include <string>
#include <unordered_set>
#endif
#ifdef LINUX
#include <malloc.h>
#endif // LINUX
#include <stdarg.h>
#include "bcnames.h"
#include "jithash.h"
#include "jitprotos.h"
#include "j9.h"
#include "j9cfg.h"
#include "j9modron.h"
#include "j9nonbuilder.h"
#include "j9consts.h"
#include "mmhook.h"
#include "mmomrhook.h"
#include "vmaccess.h"
#if JAVA_SPEC_VERSION >= 19
#include "HeapIteratorAPI.h"
#include "ContinuationHelpers.hpp"
#endif /* JAVA_SPEC_VERSION >= 19 */
#include "codegen/CodeGenerator.hpp"
#include "compile/CompilationTypes.hpp"
#include "compile/Method.hpp"
#include "compile/ResolvedMethod.hpp"
#include "control/OptimizationPlan.hpp"
#include "control/OptionsUtil.hpp"
#include "control/Recompilation.hpp"
#include "control/RecompilationInfo.hpp"
#include "control/CompilationController.hpp"
#include "control/CompilationStrategy.hpp"
#include "env/ClassLoaderTable.hpp"
#include "env/CompilerEnv.hpp"
#include "env/DependencyTable.hpp"
#include "env/IO.hpp"
#include "env/J2IThunk.hpp"
#include "env/PersistentCHTable.hpp"
#include "env/PersistentInfo.hpp"
#include "env/jittypes.h"
#include "env/ClassTableCriticalSection.hpp"
#include "env/VMAccessCriticalSection.hpp"
#include "env/VMJ9.h"
#include "env/VerboseLog.hpp"
#include "il/DataTypes.hpp"
#include "ilgen/IlGeneratorMethodDetails_inlines.hpp"
#include "infra/Monitor.hpp"
#include "infra/MonitorTable.hpp"
#include "infra/CriticalSection.hpp"
#include "optimizer/DebuggingCounters.hpp"
#include "optimizer/JProfilingBlock.hpp"
#include "runtime/CodeCacheManager.hpp"
#include "runtime/HookHelpers.hpp"
#include "runtime/MethodMetaData.h"
#include "runtime/RelocationRuntime.hpp"
#include "runtime/asmprotos.h"
#include "runtime/codertinit.hpp"
#include "control/MethodToBeCompiled.hpp"
#include "control/CompilationRuntime.hpp"
#include "control/CompilationThread.hpp"
#include "env/VMJ9.h"
#include "env/j9method.h"
#include "env/ut_j9jit.h"
#include "ilgen/J9ByteCodeIlGenerator.hpp"
#include "ilgen/J9ByteCodeIterator.hpp"
#include "runtime/IProfiler.hpp"
#include "runtime/HWProfiler.hpp"
#include "env/SystemSegmentProvider.hpp"
#if defined(J9VM_OPT_JITSERVER)
#include "control/JITServerHelpers.hpp"
#include "runtime/JITServerAOTDeserializer.hpp"
#include "runtime/JITServerIProfiler.hpp"
#include "runtime/JITServerStatisticsThread.hpp"
#include "runtime/Listener.hpp"
#include "runtime/MetricsServer.hpp"
#endif /* defined(J9VM_OPT_JITSERVER) */
#if defined(J9VM_OPT_CRIU_SUPPORT)
#include "runtime/CRRuntime.hpp"
#endif /* if defined(J9VM_OPT_CRIU_SUPPORT) */
extern "C" {
struct J9JavaVM;
}
#if defined(J9ZOS390) && defined(TR_TARGET_32BIT)
#include <stdlib.h>
#define PSAAOLD 0x224 ///< offset of current ASCB in prefixed save area (located at address 0x0)
#define ASCBLDA 0x30 ///< offset of LDA field in ASCB
#define LDASTRTA 0x3c ///< offset of user region start in LDA
#define LDASIZA 0x40 ///< offset of maximum user region size in LDA
#define LDAESTRA 0x4c ///< offset of extended user region start in LDA
#define LDAESIZA 0x50 ///< offset of maximum extended user region size in LDA
#define LDACRGTP 0x98 ///< offset of user region top in LDA
#define LDAERGTP 0x9c ///< offset of extended user region top in LDA
struct LDA {
uint32_t padding1[15]; ///< Padding
void * strta; ///< User Region Start
uint32_t siza; ///< Max size of the User Region
uint32_t padding2[2]; ///< Padding
void * estra; ///< Extended User Region Start
uint32_t esiza; ///< Max size of the Extended User Region
uint32_t padding3[17]; ///< Padding
void * crgtp; ///< User Region Top
void * ergtp; ///< Extended User Region Top
};
#endif
#ifdef J9VM_JIT_RUNTIME_INSTRUMENTATION
// extern until function is added to oti/jitprotos.h
extern "C" void shutdownJITRuntimeInstrumentation(J9JavaVM *vm);
#endif
/* 1) Regular hooks
* These fire when a normal condition occurs.
* Ie: In the case of the "jitHookInitializeSendTarget" hook,
* the VM triggers the event as its initializing the send targets for a class.
* This is part of the normal code flow.
*/
/* 2) Async hooks
* These fire when requested by an outside thread.
* The thread requesting the async event has each thread/requested thread stop at
* its next safepoint to acknowledge the event.
* The interrupted thread runs the handler and then continues its execution.
*/
void
cgOnClassUnloading(void *loaderPtr)
{
#if defined(TR_TARGET_POWER) && defined(TR_HOST_POWER) && defined(TR_TARGET_64BIT)
if (TR::Compiler->target.cpu.isPower())
TR::CodeGenerator::ppcCGOnClassUnloading(loaderPtr);
#endif
}
extern TR::Monitor *assumptionTableMutex;
extern volatile bool shutdownSamplerThread;
#if defined(AOTRT_DLL)
#if defined(J9VM_GC_DYNAMIC_CLASS_UNLOADING)
extern void rtHookClassUnload(J9HookInterface * *, UDATA , void *, void *);
extern void rtHookClassLoaderUnload(J9HookInterface * *, UDATA , void *, void *);
#endif
#endif
#ifdef FIXUP_UNALIGNED
#ifdef J9VM_ENV_LITTLE_ENDIAN
#define BC_OP_U16(bcPtr) (((*(((uint8_t*)(bcPtr))+1))<<8) + (*((uint8_t*)(bcPtr))))
#else
#define BC_OP_U16(bcPtr) (((*((uint8_t*)(bcPtr)))<<8) + (*(((uint8_t*)(bcPtr))+1)))
#endif
#else
#define BC_OP_U16(bcPtr) (*((uint16_t*)(bcPtr)))
#endif
TR::OptionSet *findOptionSet(J9Method *method, bool isAOT)
{
TR::OptionSet *optionSet = NULL;
J9ROMMethod * romMethod = J9_ROM_METHOD_FROM_RAM_METHOD(method);
J9UTF8 *className;
J9UTF8 *name;
J9UTF8 *signature;
getClassNameSignatureFromMethod(method, className, name, signature);
char *methodSignature;
char arr[1024];
int32_t len = J9UTF8_LENGTH(className) + J9UTF8_LENGTH(name) + J9UTF8_LENGTH(signature) + 3;
if (len < 1024)
methodSignature = arr;
else
methodSignature = (char *) TR_Memory::jitPersistentAlloc(len);
if (methodSignature)
{
snprintf(methodSignature, len, "%.*s.%.*s%.*s", J9UTF8_LENGTH(className), utf8Data(className), J9UTF8_LENGTH(name), utf8Data(name), J9UTF8_LENGTH(signature), utf8Data(signature));
TR_FilterBST * filter = 0;
if (TR::Options::getDebug() && TR::Options::getDebug()->getCompilationFilters())
TR::Options::getDebug()->methodSigCanBeCompiled(methodSignature, filter, TR::Method::J9);
int32_t index = filter ? filter->getOptionSet() : 0;
int32_t lineNum = filter ? filter->getLineNumber() : 0;
bool hasBackwardBranches = (J9ROMMETHOD_HAS_BACKWARDS_BRANCHES(romMethod) ? true : false);
optionSet = TR::Options::findOptionSet(index, lineNum, methodSignature, TR::Options::getInitialHotnessLevel(hasBackwardBranches), isAOT);
if (len >= 1024)
TR_Memory::jitPersistentFree(methodSignature);
}
return optionSet;
}
static void reportHook(J9VMThread *curThread, const char *name, const char *format=NULL, ...)
{
J9JITConfig * jitConfig = curThread->javaVM->jitConfig;
TR::CompilationInfo * compInfo = TR::CompilationInfo::get(jitConfig);
if ( TR::Options::getCmdLineOptions()->getVerboseOption(TR_VerboseHooks)
|| TR::Options::getCmdLineOptions()->getVerboseOption(TR_VerboseHookDetails))
{
TR_VerboseLog::CriticalSection vlogLock;
TR_VerboseLog::write(TR_Vlog_HK,"vmThread=%p hook %s ", curThread, name);
if (format)
{
va_list args;
va_start(args, format);
j9jit_vprintf(jitConfig, format, args);
va_end(args);
}
TR_VerboseLog::writeLine("");
}
}
static void reportHookFinished(J9VMThread *curThread, const char *name, const char *format=NULL, ...)
{
J9JITConfig * jitConfig = curThread->javaVM->jitConfig;
TR::CompilationInfo * compInfo = TR::CompilationInfo::get(jitConfig);
if (TR::Options::getCmdLineOptions()->getVerboseOption(TR_VerboseHookDetails))
{
TR_VerboseLog::CriticalSection vlogLock;
TR_VerboseLog::writeLine(TR_Vlog_HD,"vmThread=%p hook %s finished ", curThread, name);
if (format)
{
va_list args;
va_start(args, format);
j9jit_vprintf(jitConfig, format, args);
va_end(args);
}
}
}
static void reportHookDetail(J9VMThread *curThread, const char *name, const char *format, ...)
{
J9JITConfig * jitConfig = curThread->javaVM->jitConfig;
TR::CompilationInfo * compInfo = TR::CompilationInfo::get(jitConfig);
if (TR::Options::getCmdLineOptions()->getVerboseOption(TR_VerboseHookDetails))
{
TR_VerboseLog::CriticalSection vlogLock;
TR_VerboseLog::writeLine(TR_Vlog_HD,"vmThread=%p hook %s detail ", curThread, name);
va_list args;
va_start(args, format);
j9jit_vprintf(jitConfig, format, args);
va_end(args);
}
}
extern "C" {
extern void freeJITConfig(J9JITConfig *);
extern void stopSamplingThread(J9JITConfig *);
extern void getOutOfIdleStates(TR::CompilationInfo::TR_SamplerStates expectedState, TR::CompilationInfo *compInfo, const char* reason);
extern void getOutOfIdleStatesUnlocked(TR::CompilationInfo::TR_SamplerStates expectedState, TR::CompilationInfo *compInfo, const char* reason);
//***************************************************************************************
// Hooked by the JIT
//***************************************************************************************
int32_t encodeCount(int32_t count)
{
return (count == -1) ? 0 : (count << 1) + 1;
}
int32_t getCount(J9ROMMethod *romMethod, TR::Options *optionsJIT, TR::Options *optionsAOT)
{
int32_t count;
if (J9ROMMETHOD_HAS_BACKWARDS_BRANCHES(romMethod))
{
count = std::min(optionsJIT->getInitialBCount(), optionsAOT->getInitialBCount());
}
else
{
count = std::min(optionsJIT->getInitialCount(), optionsAOT->getInitialCount());
if (TR::Options::_smallMethodBytecodeSizeThreshold > 0)
{
uint32_t methodSize = TR::CompilationInfo::getMethodBytecodeSize(romMethod);
if ((int32_t)methodSize <= TR::Options::_smallMethodBytecodeSizeThreshold)
{
count = count << 3;
}
}
}
return count;
}
bool sharedCacheContainsProfilingInfoForMethod(J9VMThread *vmThread, TR::CompilationInfo *compInfo, J9ROMMethod * romMethod)
{
J9SharedClassConfig * scConfig = compInfo->getJITConfig()->javaVM->sharedClassConfig;
if(!scConfig)
return false;
unsigned char storeBuffer[1000];
uint32_t bufferLength=1000;
J9SharedDataDescriptor descriptor;
descriptor.address = storeBuffer;
descriptor.length = bufferLength;
descriptor.type = J9SHR_ATTACHED_DATA_TYPE_JITPROFILE;
descriptor.flags = J9SHR_ATTACHED_DATA_NO_FLAGS;
IDATA dataIsCorrupt;
TR_IPBCDataStorageHeader *store = (TR_IPBCDataStorageHeader *)scConfig->findAttachedData(vmThread, romMethod, &descriptor, &dataIsCorrupt);
if (!store)
return false;
if (store != (TR_IPBCDataStorageHeader *)descriptor.address) // a stronger check, as found can be error value
return false;
return true;
}
/// This is a helper function used by jitHookInitializeSendTarget().
/// This function calculates for the hash value for methods using method names.
/// The hash value will be eventually added to variable `count` in `jitHookInitializeSendTarget()` under some conditions.
/// The formula for the hash value is:
///
/// hashValue[0] = HASH_INIT_VALUE;
/// hashValue[i+1] = hashValue[i] * HASH_BASE_VALUE + name[i];
/// hashValue[length(name)] will be used as the hash value
static uint32_t initializeSendTargetHelperFuncHashValueForSpreading(J9Method* method)
{
// extract class name, method name, and signature
J9ROMMethod * romMethod = J9_ROM_METHOD_FROM_RAM_METHOD(method);
J9UTF8 *className;
J9UTF8 *name;
J9UTF8 *signature;
getClassNameSignatureFromMethod(method, className, name, signature);
char *classNameChar = utf8Data(className);
char *nameChar = utf8Data(name);
char *signatureChar = utf8Data(signature);
// set the base and initial value for the hash value
// const uint32_t HASH_BASE_VALUE = 33;
const uint32_t HASH_INIT_VALUE = 5381;
// get options
TR::Options * optionsJIT = TR::Options::getJITCmdLineOptions();
TR::Options * optionsAOT = TR::Options::getAOTCmdLineOptions();
// extract the CAP of the hash value
uint32_t hashValueCap;
if (J9ROMMETHOD_HAS_BACKWARDS_BRANCHES(romMethod))
hashValueCap = std::max(optionsJIT->getMaxSpreadCountLoopy(), optionsAOT->getMaxSpreadCountLoopy());
else
hashValueCap = std::max(optionsJIT->getMaxSpreadCountLoopless(), optionsAOT->getMaxSpreadCountLoopless());
// compute the hash value
uint32_t hashValue = HASH_INIT_VALUE;
for (uint32_t i = 0; i < J9UTF8_LENGTH(className); i++)
hashValue = (hashValue << 5) + hashValue + classNameChar[i];
for (uint32_t i = 0; i < J9UTF8_LENGTH(name); i++)
hashValue = (hashValue << 5) + hashValue + nameChar[i];
for (uint32_t i = 0; i < J9UTF8_LENGTH(signature); i++)
hashValue = (hashValue << 5) + hashValue + signatureChar[i];
hashValue = hashValue % hashValueCap;
return hashValue;
}
static bool highCodeCacheOccupancyThresholdReached = false;
#if defined(J9VM_OPT_JITSERVER)
static int32_t calculateCountForMethodCachedAtServer(J9ROMMethod * romMethod,
TR::Options * optionsJIT,
TR::Options * optionsAOT)
{
int32_t scount = TR_INITIAL_SCOUNT;
if (optionsAOT)
{
scount = optionsAOT->getInitialSCount();
if ((scount == TR_QUICKSTART_INITIAL_SCOUNT) || (scount == TR_INITIAL_SCOUNT))
{
// If scount is not user specified (coarse way due to info being lost
// from options parsing)
scount= std::min(getCount(romMethod, optionsJIT, optionsAOT),
optionsAOT->getInitialSCount());
}
}
return scount;
}
#endif // J9VM_OPT_JITSERVER
static void jitHookInitializeSendTarget(J9HookInterface * * hook, UDATA eventNum, void * eventData, void * userData)
{
J9VMInitializeSendTargetEvent * event = (J9VMInitializeSendTargetEvent *)eventData;
J9VMThread * vmThread = event->currentThread;
J9JITConfig* jitConfig = vmThread->javaVM->jitConfig;
TR::CompilationInfo * compInfo = TR::CompilationInfo::get(jitConfig);
if ((jitConfig->runtimeFlags & J9JIT_DEFER_JIT) != 0)
return; // No need to set counts in this mode
TR_J9VMBase * fe = TR_J9VMBase::get(jitConfig, vmThread);
J9Method * method = event->method;
J9ROMMethod * romMethod = fe->getROMMethodFromRAMMethod(method);
// Allow native and abstract methods to be initialized by the interpreter
if (romMethod->modifiers & (J9AccAbstract | J9AccNative))
{
TR::CompilationInfo::setInitialInvocationCountUnsynchronized(method,0);
return;
}
TR::Options * optionsJIT = TR::Options::getJITCmdLineOptions();
TR::Options * optionsAOT = TR::Options::getAOTCmdLineOptions();
method->methodRunAddress = jitGetCountingSendTarget(vmThread, method);
bool countInOptionSet = false;
if (TR::Options::getJITCmdLineOptions()->anOptionSetContainsACountValue())
{
TR::OptionSet * optionSet = findOptionSet(method, false);
if (optionSet)
{
optionsJIT = optionSet->getOptions();
countInOptionSet = true;
}
}
#if defined(J9VM_OPT_JITSERVER)
bool methodCachedAtServer = false;
PersistentUnorderedSet<std::string> *serverAOTMethodSet =
(PersistentUnorderedSet<std::string> *) jitConfig->serverAOTMethodSet;
if (serverAOTMethodSet != NULL)
{
// Construct a signature
J9UTF8 *className;
J9UTF8 *name;
J9UTF8 *signature;
getClassNameSignatureFromMethod(method, className, name, signature);
// SigLen calculation as used in TRJ9VMBase::printTruncatedSignature
int32_t sigLen = J9UTF8_LENGTH(className) + J9UTF8_LENGTH(name) +
J9UTF8_LENGTH(signature) + 2;
if (sigLen < 1024)
{
char sigC[1024];
snprintf(sigC, sizeof(sigC), "%.*s.%.*s%.*s",
J9UTF8_LENGTH(className), utf8Data(className),
J9UTF8_LENGTH(name), utf8Data(name),
J9UTF8_LENGTH(signature), utf8Data(signature));
// contains
methodCachedAtServer =
(serverAOTMethodSet->find(std::string(sigC)) != serverAOTMethodSet->end());
if (TR::Options::getVerboseOption(TR_VerboseJITServer)
&& TR::Options::getVerboseOption(TR_VerboseCounts))
if (methodCachedAtServer)
TR_VerboseLog::writeLineLocked(TR_Vlog_JITServer,
"Method %s was cached at the server",
sigC);
}
}
#endif // J9VM_OPT_JITSERVER
if (TR::Options::getAOTCmdLineOptions()->anOptionSetContainsACountValue())
{
TR::OptionSet * optionSet = findOptionSet(method, true);
if (optionSet)
{
optionsAOT = optionSet->getOptions();
countInOptionSet = true;
}
}
int32_t count = -1; // means we didn't set the value yet
{
#if defined(J9VM_OPT_CRIU_SUPPORT)
bool cpAllowedAndDebugOnRestoreEnabled
= jitConfig->javaVM->internalVMFunctions->isDebugOnRestoreEnabled(jitConfig->javaVM)
&& jitConfig->javaVM->internalVMFunctions->isCheckpointAllowed(jitConfig->javaVM);
#endif /* defined(J9VM_OPT_CRIU_SUPPORT) */
bool sccCounts =
#if defined(J9VM_OPT_CRIU_SUPPORT)
(cpAllowedAndDebugOnRestoreEnabled && jitConfig->javaVM->sharedClassConfig) ||
#endif /* defined(J9VM_OPT_CRIU_SUPPORT) */
TR::Options::sharedClassCache();
J9ROMClass *declaringClazz = J9_CLASS_FROM_METHOD(method)->romClass;
J9UTF8 * className = J9ROMCLASS_CLASSNAME(declaringClazz);
J9UTF8 * name = J9ROMMETHOD_NAME(romMethod);
if (J9UTF8_LENGTH(className) == 36
&& J9UTF8_LENGTH(name) == 21
&& 0==memcmp(utf8Data(className), "com/ibm/rmi/io/FastPathForCollocated", 36)
&& 0==memcmp(utf8Data(J9ROMMETHOD_NAME(romMethod)), "isVMDeepCopySupported", 21)
)
{
count = 0;
}
else if (J9UTF8_LENGTH(className) == 39
&& J9UTF8_LENGTH(name) == 9
&& 0 == memcmp(utf8Data(className), "java/util/concurrent/ThreadPoolExecutor", 39)
&& 0 == memcmp(utf8Data(J9ROMMETHOD_NAME(romMethod)), "runWorker", 9)
)
{
count = 0;
}
else if (highCodeCacheOccupancyThresholdReached && !countInOptionSet && !TR::Options::getCountsAreProvidedByUser())
{
count = J9ROMMETHOD_HAS_BACKWARDS_BRANCHES(romMethod) ?
TR::Options::getHighCodeCacheOccupancyBCount() :
TR::Options::getHighCodeCacheOccupancyCount();
}
else if (sccCounts)
{
// The default FE may not have TR_J9SharedCache object because the FE may have
// been created before options were processed.
TR_J9VMBase *fej9 = TR_J9VMBase::get(jitConfig, vmThread, TR_J9VMBase::AOT_VM);
TR_J9SharedCache *sc = fej9 ? fej9->sharedCache() : NULL;
#if defined(J9VM_INTERP_AOT_COMPILE_SUPPORT) && defined(J9VM_OPT_SHARED_CLASSES) && (defined(TR_HOST_X86) || defined(TR_HOST_POWER) || defined(TR_HOST_S390) || defined(TR_HOST_ARM) || defined(TR_HOST_ARM64))
if (sc && sc->isClassInSharedCache(J9_CLASS_FROM_METHOD(method)))
{
PORT_ACCESS_FROM_JAVAVM(jitConfig->javaVM);
I_64 sharedQueryTime = 0;
if (optionsAOT->getOption(TR_EnableSharedCacheTiming))
sharedQueryTime = j9time_hires_clock(); // may not be good for SMP
bool methodExistsInSCC = jitConfig->javaVM->sharedClassConfig->existsCachedCodeForROMMethod(vmThread, romMethod);
#if defined(J9VM_OPT_CRIU_SUPPORT)
if (methodExistsInSCC && cpAllowedAndDebugOnRestoreEnabled)
compInfo->getCRRuntime()->pushImportantMethodForCR(method);
#endif /* defined(J9VM_OPT_CRIU_SUPPORT) */
if (methodExistsInSCC
#if defined(J9VM_OPT_CRIU_SUPPORT)
&& !cpAllowedAndDebugOnRestoreEnabled
#endif /* defined(J9VM_OPT_CRIU_SUPPORT) */
)
{
if (auto dependencyTable = compInfo->getPersistentInfo()->getAOTDependencyTable())
{
bool dependenciesSatisfied = false;
// TODO: Obey user counts if they are set for this method
//
// TODO: The initial count for unsatisfied dependencies should
// be revisited. It can likely be lower, particularly if AOT
// loads are suppressed if dependencies are unsatisfied,
// though remember that counts can decrease faster in the warm
// run due to sampling.
if (dependencyTable->trackMethod(vmThread, method, romMethod, dependenciesSatisfied))
count = dependenciesSatisfied ? 0 : TR_DEFAULT_INITIAL_COUNT;
}
if (count == -1)
{
int32_t scount = optionsAOT->getInitialSCount();
uint16_t newScount = 0;
if (sc && sc->isHint(method, TR_HintFailedValidation, &newScount))
{
if ((scount == TR_QUICKSTART_INITIAL_SCOUNT) || (scount == TR_INITIAL_SCOUNT))
{ // If scount is not user specified (coarse way due to info being lost from options parsing)
// TODO: Is casting the best thing to do here?
scount= std::min(getCount(romMethod, optionsJIT, optionsAOT), static_cast<int32_t>(newScount) ); // Find what would've been normal count for this method and
// make sure new scount isn't larger than that
if (optionsAOT->getVerboseOption(TR_VerboseSCHints) || optionsJIT->getVerboseOption(TR_VerboseSCHints))
TR_VerboseLog::writeLineLocked(TR_Vlog_SCHINTS,"Found hint in sc, increase scount to: %d, wanted scount: %d", scount, newScount);
}
}
count = scount;
}
compInfo->incrementNumMethodsFoundInSharedCache();
}
// AOT Body not in SCC, so scount was not set
else if (!TR::Options::getCountsAreProvidedByUser() && !countInOptionSet)
{
bool useLowerCountsForAOTCold = false;
if (TR::Options::getCmdLineOptions()->getOption(TR_LowerCountsForAotCold) && compInfo->isWarmSCC() == TR_no)
{
// Because C-interpreter is slower we need to rely more on jitted code
// This means compiling more, but we have to be careful.
// Let's use some smaller than normal counts in the cold run (to avoid
// extra compilations in the warm runs), but only if
//
// 1) The Default SCC isn't used - because we don't want to increase footprint
//
// OR
//
// 1) Quickstart - because we don't risk losing iprofiling info
// 2) GracePeriod - because we want to limit the number of 'extra'
// compilations and short apps are affected more
// 3) Bootstrap - same as above, plus if these methods get into the
// SCC I would rather have non-app specific methods
//
// The danger is that very small applications that don't even get to AOT 200 methods
// may think that the runs are always cold
// J9SHR_RUNTIMEFLAG_ENABLE_CACHE_NON_BOOT_CLASSES is a good proxy for whether the
// Default SCC is set because, when -Xshareclasses option is used, by default non
// bootstrap loaded classes are put into the SCC. However, if the -Xshareclasses
// option isn't used, then the Default SCC only contains bootstrap loaded classes.
if (J9_SHARED_CACHE_DEFAULT_BOOT_SHARING(jitConfig->javaVM) &&
J9_ARE_ALL_BITS_SET(jitConfig->javaVM->sharedClassConfig->runtimeFlags, J9SHR_RUNTIMEFLAG_ENABLE_CACHE_NON_BOOT_CLASSES))
{
useLowerCountsForAOTCold = true;
}
else if (compInfo->getPersistentInfo()->getElapsedTime() <= (uint64_t)compInfo->getPersistentInfo()->getClassLoadingPhaseGracePeriod() &&
TR::Options::isQuickstartDetected() &&
fe->isClassLibraryMethod((TR_OpaqueMethodBlock *)method))
{
useLowerCountsForAOTCold = true;
}
}
if (useLowerCountsForAOTCold)
{
// TODO: modify the function that reads a specified count such that
// if the user specifies a count or bcount on the command line that is obeyed
// and we don't try the following line
count = J9ROMMETHOD_HAS_BACKWARDS_BRANCHES(romMethod) ?
std::min(optionsJIT->getInitialColdRunBCount(), optionsAOT->getInitialColdRunBCount()) :
std::min(optionsJIT->getInitialColdRunCount(), optionsAOT->getInitialColdRunCount());
}
// Increase counts for methods from non-bootstrap classes to improve throughput
else if (TR::Options::getCmdLineOptions()->getOption(TR_IncreaseCountsForNonBootstrapMethods))
{
if (!fe->isClassLibraryMethod((TR_OpaqueMethodBlock *)method))
count = J9ROMMETHOD_HAS_BACKWARDS_BRANCHES(romMethod) ? TR_DEFAULT_INITIAL_BCOUNT : TR_DEFAULT_INITIAL_COUNT;
}
// We may lower or increase the counts based on TR_HintMethodCompiledDuringStartup
if (count == -1 && // Not yet changed
jitConfig->javaVM->phase != J9VM_PHASE_NOT_STARTUP &&
(TR_HintMethodCompiledDuringStartup & TR::Options::getAOTCmdLineOptions()->getEnableSCHintFlags()) && sc)
{
bool wasCompiledDuringStartup = sc->isHint(method, TR_HintMethodCompiledDuringStartup);
if (wasCompiledDuringStartup)
{
// Lower the counts for any method that doesn't have an AOT body,
// but we know it has been compiled in previous runs.
if (TR::Options::getCmdLineOptions()->getOption(TR_ReduceCountsForMethodsCompiledDuringStartup))
count = TR::Options::getCountForMethodsCompiledDuringStartup();
}
else // method was not compiled during startup
{
if (TR::Options::getCmdLineOptions()->getOption(TR_IncreaseCountsForMethodsCompiledOutsideStartup) &&
TR::Options::startupTimeMatters() == TR_maybe) // For TR_no the counts are already high, for TR_yes we cannot get in here
count = J9ROMMETHOD_HAS_BACKWARDS_BRANCHES(romMethod) ? TR_DEFAULT_INITIAL_BCOUNT : TR_DEFAULT_INITIAL_COUNT;
}
}
}
if (optionsAOT->getOption(TR_EnableSharedCacheTiming))
{
sharedQueryTime = j9time_hires_delta(sharedQueryTime, j9time_hires_clock(), J9PORT_TIME_DELTA_IN_MICROSECONDS);
compInfo->setAotQueryTime(compInfo->getAotQueryTime() + (UDATA)sharedQueryTime);
}
}
else // ROM class not in shared class cache (no space or ineligible - maybe because of implicit SCC)
{
// For an implicit SCC, if there is enough CPU power to compile sooner,
// do so by using lower counts, but only for the classes loaded during startup
if (!TR::Options::getCountsAreProvidedByUser() && !countInOptionSet)
{
if (TR::Options::getCmdLineOptions()->getOption(TR_UseLowerCountsForNonSCCMethodsDuringStartup) &&
J9_ARE_NO_BITS_SET(jitConfig->javaVM->sharedClassConfig->runtimeFlags, J9SHR_RUNTIMEFLAG_ENABLE_CACHE_NON_BOOT_CLASSES) &&
(jitConfig->javaVM->phase != J9VM_PHASE_NOT_STARTUP) &&
TR::Compiler->target.numberOfProcessors() >= TR_NUMPROC_FOR_LARGE_SMP)
{
count = getCount(romMethod, optionsJIT, optionsAOT); // counts are lower when SCC is enabled
}
#if !defined(J9ZOS390) // Do not change the counts on zos at the moment since the
// shared cache capacity is higher on this platform and by
// increasing counts we could end up significantly impacting startup
else
{
if (TR::Options::getCmdLineOptions()->getOption(TR_UseHigherCountsForNonSCCMethods))
count = J9ROMMETHOD_HAS_BACKWARDS_BRANCHES(romMethod) ? TR_DEFAULT_INITIAL_BCOUNT : TR_DEFAULT_INITIAL_COUNT;
}
#endif // !J9ZOS390
}
}
#endif // defined(J9VM_INTERP_AOT_COMPILE_SUPPORT) && defined(J9VM_OPT_SHARED_CLASSES) && (defined(TR_HOST_X86) || defined(TR_HOST_POWER) || defined(TR_HOST_S390) || defined(TR_HOST_ARM) || defined(TR_HOST_ARM64))
} // if (TR::Options::sharedClassCache())
#if defined(J9VM_OPT_JITSERVER)
// If the method is cached at the server side, set the count to the lower number
// regardless of whether the count has been set before
if (methodCachedAtServer)
{
int32_t serverCount =
calculateCountForMethodCachedAtServer(romMethod, optionsJIT, optionsAOT);
if (count == -1)
count = serverCount;
else
count = std::min(count, serverCount);
}
#endif // J9VM_OPT_JITSERVER
if (count == -1) // count didn't change yet
{
if (!TR::Options::getCountsAreProvidedByUser() &&
fe->isClassLibraryMethod((TR_OpaqueMethodBlock *)method))
count = J9ROMMETHOD_HAS_BACKWARDS_BRANCHES(romMethod) ? TR::Options::getCountForLoopyBootstrapMethods() : TR::Options::getCountForLooplessBootstrapMethods();
if (count == -1)
count = getCount(romMethod, optionsJIT, optionsAOT);
// If add-spreading-invocation mode is enabled, add a hash value (hashed from method name) to count
if (optionsAOT->getOption(TR_EnableCompilationSpreading) || optionsJIT->getOption(TR_EnableCompilationSpreading))
{
count += initializeSendTargetHelperFuncHashValueForSpreading(method);
}
else if (TR::Options::getCmdLineOptions()->getOption(TR_EnableEarlyCompilationDuringIdleCpu))
{
// Set only a fraction of a count to accelerate compilations
if (count > 20)
count = count * TR::Options::_countPercentageForEarlyCompilation / 100;
// TODO: disable this mechanism after an hour or so to conserve idle time
}
}
}
// Option to display chosen counts to track possible bugs
if (optionsJIT->getVerboseOption(TR_VerboseCounts))
{
char buffer[500];
fe->printTruncatedSignature(buffer, 500, (TR_OpaqueMethodBlock *) method);
TR_VerboseLog::writeLineLocked(TR_Vlog_PERF, "Setting count=%d for %s", count, buffer);
}
TR::CompilationInfo::setInitialInvocationCountUnsynchronized(method,count);
if (TR::Options::getJITCmdLineOptions()->getOption(TR_DumpInitialMethodNamesAndCounts) || TR::Options::getAOTCmdLineOptions()->getOption(TR_DumpInitialMethodNamesAndCounts))
{
bool containsInfo = sharedCacheContainsProfilingInfoForMethod(vmThread, compInfo, romMethod);
char buf[3072];
J9UTF8 * className = J9ROMCLASS_CLASSNAME(J9_CLASS_FROM_METHOD(method)->romClass);
J9UTF8 * name = J9ROMMETHOD_NAME(J9_ROM_METHOD_FROM_RAM_METHOD(method));
J9UTF8 * signature = J9ROMMETHOD_SIGNATURE(J9_ROM_METHOD_FROM_RAM_METHOD(method));
snprintf(buf, sizeof(buf), "%.*s.%.*s%.*s", J9UTF8_LENGTH(className), utf8Data(className), J9UTF8_LENGTH(name), utf8Data(name), J9UTF8_LENGTH(signature), utf8Data(signature));
printf("Initial: Signature %s Count %d isLoopy %d isAOT %" OMR_PRIuPTR " is in SCC %d SCCContainsProfilingInfo %d \n",buf,TR::CompilationInfo::getInvocationCount(method),J9ROMMETHOD_HAS_BACKWARDS_BRANCHES(romMethod),
TR::Options::sharedClassCache() ? jitConfig->javaVM->sharedClassConfig->existsCachedCodeForROMMethod(vmThread, romMethod) : 0,
TR::Options::sharedClassCache() ? TR_J9VMBase::get(jitConfig, vmThread, TR_J9VMBase::AOT_VM)->sharedCache()->isClassInSharedCache(J9_CLASS_FROM_METHOD(method)) : 0,containsInfo) ; fflush(stdout);
}
}
#if defined(J9VM_INTERP_PROFILING_BYTECODES)
static int32_t interpreterProfilingState = IPROFILING_STATE_OFF;
static int32_t interpreterProfilingRecordsCount = 0; // reset when state changes to IPROFILING_STATE_GOING_OFF
static int32_t interpreterProfilingJITSamples = 0;
static int32_t interpreterProfilingINTSamples = 0;
static int32_t interpreterProfilingMonitoringWindow = 0;
static bool interpreterProfilingWasOnAtStartup = false;
/**
* J9 VM hook, called when the profiling bytecode buffer is full.
*/
static void jitHookBytecodeProfiling(J9HookInterface * * hook, UDATA eventNum, void * eventData, void * userData);
static void turnOnInterpreterProfiling(J9JavaVM* javaVM, TR::CompilationInfo * compInfo)
{
if (interpreterProfilingState == IPROFILING_STATE_OFF)
{
TR_J9VMBase * vmj9 = (TR_J9VMBase *)(TR_J9VMBase::get(javaVM->jitConfig, 0));
TR_IProfiler *iProfiler = vmj9->getIProfiler();
if (iProfiler->getProfilerMemoryFootprint() >= TR::Options::_iProfilerMemoryConsumptionLimit)
return;
J9HookInterface ** hook = javaVM->internalVMFunctions->getVMHookInterface(javaVM);
interpreterProfilingRecordsCount = 0;
interpreterProfilingState = IPROFILING_STATE_ON;
interpreterProfilingJITSamples = 0;
PORT_ACCESS_FROM_JAVAVM(javaVM);
if ((*hook)->J9HookRegisterWithCallSite(hook, J9HOOK_VM_PROFILING_BYTECODE_BUFFER_FULL, jitHookBytecodeProfiling, OMR_GET_CALLSITE(), NULL))
{
j9tty_printf(PORTLIB, "Error: Unable to install J9HOOK_VM_PROFILING_BYTECODE_BUFFER_FULL listener\n");
return;
}
else
{
if (TR::Options::getCmdLineOptions()->getOption(TR_VerboseInterpreterProfiling))
{
TR_VerboseLog::writeLineLocked(TR_Vlog_IPROFILER,"t=%6u IProfiler reactivated...", (uint32_t)compInfo->getPersistentInfo()->getElapsedTime());
}
}
}
}
#endif
#if defined(J9VM_JIT_DYNAMIC_LOOP_TRANSFER)
static TR_YesNoMaybe shouldInitiateDLT(J9DLTInformationBlock *dltInfo, int32_t idx, bool *bcRepeats, int32_t *hitCnt)
{
static int32_t triggerCount = -1;
if (triggerCount == -1)
{
static char *envTrigger = feGetEnv("TR_DLTcount");
if (envTrigger == NULL)
{
triggerCount = 3;
}
else
triggerCount = atoi(envTrigger);
}
*bcRepeats = false;
*hitCnt = -1; // -1 means unknown
if (triggerCount <= 1)
return TR_yes;
J9Method *currentMethod = dltInfo->methods[idx];
int32_t hitCount=0, loopCnt=0, bcIdx = dltInfo->bcIndex[idx];
idx = (idx==0)?(J9DLT_HISTORY_SIZE-1):(idx-1);
while (loopCnt < J9DLT_HISTORY_SIZE-1)
{
loopCnt++;
if (dltInfo->methods[idx] == currentMethod)
{
if (dltInfo->bcIndex[idx] >= bcIdx)
*bcRepeats = true;
hitCount++;
}
idx = (idx==0)?(J9DLT_HISTORY_SIZE-1):(idx-1);
if (loopCnt==triggerCount-1 && hitCount==triggerCount-1)
return TR_maybe;
}
*hitCnt = hitCount;
if (hitCount>=triggerCount)
return TR_maybe;
void *extra = TR::CompilationInfo::getPCIfCompiled(currentMethod);
if(extra && !TR::Options::getCmdLineOptions()->getOption(TR_DisableFastDLTOnLongRunningInterpreter))
{
TR_PersistentJittedBodyInfo *bodyInfo = TR::Recompilation::getJittedBodyInfoFromPC(extra);
if (bodyInfo && bodyInfo->isLongRunningInterpreted())
return TR_yes;
}
return TR_no;
}
void *jitLookupDLT(J9VMThread *currentThread, J9Method *method, UDATA bcIndex)
{
J9JITConfig * jitConfig = currentThread->javaVM->jitConfig;
if (!jitConfig)
return 0;
TR::CompilationInfo *compInfo = TR::CompilationInfo::get(jitConfig);
void *dltEntry = compInfo->searchForDLTRecord(method, bcIndex);
if (!dltEntry)
return 0;
J9DLTInformationBlock *dltBlock = &(currentThread->dltBlock);
dltBlock->dltSP = (uintptr_t)CONVERT_TO_RELATIVE_STACK_OFFSET(currentThread, currentThread->sp);
dltBlock->dltEntry = dltEntry;
return (void *)1;
}
static UDATA dltTestIterator(J9VMThread * currentThread, J9StackWalkState * walkState)
{
switch(walkState->framesWalked)
{
case 1 :
if (((UDATA) walkState->pc <= J9SF_MAX_SPECIAL_FRAME_TYPE) || (walkState->pc == walkState->walkThread->javaVM->callInReturnPC))
return J9_STACKWALK_KEEP_ITERATING;
if (walkState->jitInfo!=NULL)
return J9_STACKWALK_STOP_ITERATING;
walkState->userData1 = (void *)1;
return J9_STACKWALK_STOP_ITERATING;
break;
case 2 :
if (((UDATA) walkState->pc <= J9SF_MAX_SPECIAL_FRAME_TYPE) || (walkState->pc == walkState->walkThread->javaVM->callInReturnPC))
return J9_STACKWALK_STOP_ITERATING;
if (walkState->jitInfo!=NULL)
return J9_STACKWALK_STOP_ITERATING;
// We can stop at this point: candidate for sync transfer
walkState->userData1 = (void *)2;
return J9_STACKWALK_STOP_ITERATING;
break;
case 3 : // unused currently
if (walkState->jitInfo!=NULL || ((UDATA) walkState->pc <= J9SF_MAX_SPECIAL_FRAME_TYPE) ||
(walkState->pc == walkState->walkThread->javaVM->callInReturnPC) || (*walkState->bp & J9SF_A0_INVISIBLE_TAG))
return J9_STACKWALK_STOP_ITERATING;
break;
}
return J9_STACKWALK_KEEP_ITERATING;
}
static void emptyJitGCMapCheck(J9VMThread * currentThread, J9StackWalkState * walkState, j9object_t * objectSlot, const void * stackLocation)
{
return;
}
static void jitGCMapCheck(J9VMThread* vmThread, IDATA handlerKey, void* userData)
{
J9StackWalkState walkState;
walkState.flags = J9_STACKWALK_ITERATE_O_SLOTS | J9_STACKWALK_ITERATE_HIDDEN_JIT_FRAMES | J9_STACKWALK_CHECK_I_SLOTS_FOR_OBJECTS;
walkState.objectSlotWalkFunction = emptyJitGCMapCheck;
walkState.maxFrames = 2;
walkState.walkThread = vmThread;
walkState.userData1=0;
static char *verbose = feGetEnv("TR_GCMapCheckVerbose");
if (verbose)
walkState.userData1 = (void*)((uintptr_t) walkState.userData1 | 1);
static char *local = feGetEnv("TR_GCMapCheckLocalScavenge");
if (local)
walkState.userData1 = (void*)((uintptr_t) walkState.userData1 | 2);
static char *global = feGetEnv("TR_GCMapCheckGlobalScavenge");
if (global)
walkState.userData1 = (void*)((uintptr_t) walkState.userData1 | 4);
vmThread->javaVM->walkStackFrames(vmThread, &walkState);
return;
}
void DLTLogic(J9VMThread* vmThread, TR::CompilationInfo *compInfo)
{
#define SIG_SZ 150
char sig[SIG_SZ];
if (!TR::Options::canJITCompile() ||
TR::Options::getCmdLineOptions()->getOption(TR_FullSpeedDebug) ||
TR::Options::getCmdLineOptions()->getOption(TR_DisableDynamicLoopTransfer) )
return;
if (TR::Options::_compilationDelayTime > 0 && // feature enabled
TR::Options::_compilationDelayTime * 1000 > compInfo->getPersistentInfo()->getElapsedTime())
return;
J9StackWalkState walkState;
walkState.maxFrames = 3;
walkState.userData1 = 0;
walkState.walkThread = vmThread;
walkState.frameWalkFunction = dltTestIterator;
walkState.flags = J9_STACKWALK_ITERATE_FRAMES | J9_STACKWALK_COUNT_SPECIFIED | J9_STACKWALK_SKIP_INLINES;
vmThread->javaVM->walkStackFrames(vmThread, &walkState);
uint8_t * startPC = 0;
if (walkState.userData1 == 0)
startPC = (uint8_t *)-1;
J9DLTInformationBlock *dltBlock = &(vmThread->dltBlock);
int32_t idx = dltBlock->cursor + 1;
J9ROMMethod *romMethod = NULL;
bool bcRepeats;
void *extra = NULL;
if (startPC!=(uint8_t *)-1 && walkState.method!=0)
romMethod = J9_ROM_METHOD_FROM_RAM_METHOD(walkState.method);
idx = (idx==J9DLT_HISTORY_SIZE) ? 0 : idx;
dltBlock->cursor = idx;
if (startPC ||