--- a/src/hotspot/share/runtime/compilationPolicy.cpp Mon Oct 07 16:48:42 2019 +0200
+++ /dev/null Thu Jan 01 00:00:00 1970 +0000
@@ -1,506 +0,0 @@
-/*
- * Copyright (c) 2000, 2019, Oracle and/or its affiliates. All rights reserved.
- * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
- *
- * This code is free software; you can redistribute it and/or modify it
- * under the terms of the GNU General Public License version 2 only, as
- * published by the Free Software Foundation.
- *
- * This code is distributed in the hope that it will be useful, but WITHOUT
- * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
- * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
- * version 2 for more details (a copy is included in the LICENSE file that
- * accompanied this code).
- *
- * You should have received a copy of the GNU General Public License version
- * 2 along with this work; if not, write to the Free Software Foundation,
- * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
- *
- * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
- * or visit www.oracle.com if you need additional information or have any
- * questions.
- *
- */
-
-#include "precompiled.hpp"
-#include "classfile/classLoaderDataGraph.inline.hpp"
-#include "code/compiledIC.hpp"
-#include "code/nmethod.hpp"
-#include "code/scopeDesc.hpp"
-#include "interpreter/interpreter.hpp"
-#include "memory/resourceArea.hpp"
-#include "oops/methodData.hpp"
-#include "oops/method.inline.hpp"
-#include "oops/oop.inline.hpp"
-#include "prims/nativeLookup.hpp"
-#include "runtime/compilationPolicy.hpp"
-#include "runtime/frame.hpp"
-#include "runtime/handles.inline.hpp"
-#include "runtime/stubRoutines.hpp"
-#include "runtime/thread.hpp"
-#include "runtime/tieredThresholdPolicy.hpp"
-#include "runtime/vframe.hpp"
-#include "runtime/vmOperations.hpp"
-#include "utilities/events.hpp"
-#include "utilities/globalDefinitions.hpp"
-
-#ifdef COMPILER1
-#include "c1/c1_Compiler.hpp"
-#endif
-#ifdef COMPILER2
-#include "opto/c2compiler.hpp"
-#endif
-
-CompilationPolicy* CompilationPolicy::_policy;
-
-// Determine compilation policy based on command line argument
-void compilationPolicy_init() {
- #ifdef TIERED
- if (TieredCompilation) {
- CompilationPolicy::set_policy(new TieredThresholdPolicy());
- } else {
- CompilationPolicy::set_policy(new SimpleCompPolicy());
- }
- #else
- CompilationPolicy::set_policy(new SimpleCompPolicy());
- #endif
-
- CompilationPolicy::policy()->initialize();
-}
-
-// Returns true if m must be compiled before executing it
-// This is intended to force compiles for methods (usually for
-// debugging) that would otherwise be interpreted for some reason.
-bool CompilationPolicy::must_be_compiled(const methodHandle& m, int comp_level) {
- // Don't allow Xcomp to cause compiles in replay mode
- if (ReplayCompiles) return false;
-
- if (m->has_compiled_code()) return false; // already compiled
- if (!can_be_compiled(m, comp_level)) return false;
-
- return !UseInterpreter || // must compile all methods
- (UseCompiler && AlwaysCompileLoopMethods && m->has_loops() && CompileBroker::should_compile_new_jobs()); // eagerly compile loop methods
-}
-
-void CompilationPolicy::compile_if_required(const methodHandle& selected_method, TRAPS) {
- if (must_be_compiled(selected_method)) {
- // This path is unusual, mostly used by the '-Xcomp' stress test mode.
-
- // Note: with several active threads, the must_be_compiled may be true
- // while can_be_compiled is false; remove assert
- // assert(CompilationPolicy::can_be_compiled(selected_method), "cannot compile");
- if (!THREAD->can_call_java() || THREAD->is_Compiler_thread()) {
- // don't force compilation, resolve was on behalf of compiler
- return;
- }
- if (selected_method->method_holder()->is_not_initialized()) {
- // 'is_not_initialized' means not only '!is_initialized', but also that
- // initialization has not been started yet ('!being_initialized')
- // Do not force compilation of methods in uninitialized classes.
- // Note that doing this would throw an assert later,
- // in CompileBroker::compile_method.
- // We sometimes use the link resolver to do reflective lookups
- // even before classes are initialized.
- return;
- }
- CompileBroker::compile_method(selected_method, InvocationEntryBci,
- CompilationPolicy::policy()->initial_compile_level(),
- methodHandle(), 0, CompileTask::Reason_MustBeCompiled, CHECK);
- }
-}
-
-// Returns true if m is allowed to be compiled
-bool CompilationPolicy::can_be_compiled(const methodHandle& m, int comp_level) {
- // allow any levels for WhiteBox
- assert(WhiteBoxAPI || comp_level == CompLevel_all || is_compile(comp_level), "illegal compilation level");
-
- if (m->is_abstract()) return false;
- if (DontCompileHugeMethods && m->code_size() > HugeMethodLimit) return false;
-
- // Math intrinsics should never be compiled as this can lead to
- // monotonicity problems because the interpreter will prefer the
- // compiled code to the intrinsic version. This can't happen in
- // production because the invocation counter can't be incremented
- // but we shouldn't expose the system to this problem in testing
- // modes.
- if (!AbstractInterpreter::can_be_compiled(m)) {
- return false;
- }
- if (comp_level == CompLevel_all) {
- if (TieredCompilation) {
- // enough to be compilable at any level for tiered
- return !m->is_not_compilable(CompLevel_simple) || !m->is_not_compilable(CompLevel_full_optimization);
- } else {
- // must be compilable at available level for non-tiered
- return !m->is_not_compilable(CompLevel_highest_tier);
- }
- } else if (is_compile(comp_level)) {
- return !m->is_not_compilable(comp_level);
- }
- return false;
-}
-
-// Returns true if m is allowed to be osr compiled
-bool CompilationPolicy::can_be_osr_compiled(const methodHandle& m, int comp_level) {
- bool result = false;
- if (comp_level == CompLevel_all) {
- if (TieredCompilation) {
- // enough to be osr compilable at any level for tiered
- result = !m->is_not_osr_compilable(CompLevel_simple) || !m->is_not_osr_compilable(CompLevel_full_optimization);
- } else {
- // must be osr compilable at available level for non-tiered
- result = !m->is_not_osr_compilable(CompLevel_highest_tier);
- }
- } else if (is_compile(comp_level)) {
- result = !m->is_not_osr_compilable(comp_level);
- }
- return (result && can_be_compiled(m, comp_level));
-}
-
-bool CompilationPolicy::is_compilation_enabled() {
- // NOTE: CompileBroker::should_compile_new_jobs() checks for UseCompiler
- return CompileBroker::should_compile_new_jobs();
-}
-
-CompileTask* CompilationPolicy::select_task_helper(CompileQueue* compile_queue) {
- // Remove unloaded methods from the queue
- for (CompileTask* task = compile_queue->first(); task != NULL; ) {
- CompileTask* next = task->next();
- if (task->is_unloaded()) {
- compile_queue->remove_and_mark_stale(task);
- }
- task = next;
- }
-#if INCLUDE_JVMCI
- if (UseJVMCICompiler && !BackgroundCompilation) {
- /*
- * In blocking compilation mode, the CompileBroker will make
- * compilations submitted by a JVMCI compiler thread non-blocking. These
- * compilations should be scheduled after all blocking compilations
- * to service non-compiler related compilations sooner and reduce the
- * chance of such compilations timing out.
- */
- for (CompileTask* task = compile_queue->first(); task != NULL; task = task->next()) {
- if (task->is_blocking()) {
- return task;
- }
- }
- }
-#endif
- return compile_queue->first();
-}
-
-#ifndef PRODUCT
-void SimpleCompPolicy::trace_osr_completion(nmethod* osr_nm) {
- if (TraceOnStackReplacement) {
- if (osr_nm == NULL) tty->print_cr("compilation failed");
- else tty->print_cr("nmethod " INTPTR_FORMAT, p2i(osr_nm));
- }
-}
-#endif // !PRODUCT
-
-void SimpleCompPolicy::initialize() {
- // Setup the compiler thread numbers
- if (CICompilerCountPerCPU) {
- // Example: if CICompilerCountPerCPU is true, then we get
- // max(log2(8)-1,1) = 2 compiler threads on an 8-way machine.
- // May help big-app startup time.
- _compiler_count = MAX2(log2_int(os::active_processor_count())-1,1);
- // Make sure there is enough space in the code cache to hold all the compiler buffers
- size_t buffer_size = 1;
-#ifdef COMPILER1
- buffer_size = is_client_compilation_mode_vm() ? Compiler::code_buffer_size() : buffer_size;
-#endif
-#ifdef COMPILER2
- buffer_size = is_server_compilation_mode_vm() ? C2Compiler::initial_code_buffer_size() : buffer_size;
-#endif
- int max_count = (ReservedCodeCacheSize - (CodeCacheMinimumUseSpace DEBUG_ONLY(* 3))) / (int)buffer_size;
- if (_compiler_count > max_count) {
- // Lower the compiler count such that all buffers fit into the code cache
- _compiler_count = MAX2(max_count, 1);
- }
- FLAG_SET_ERGO(CICompilerCount, _compiler_count);
- } else {
- _compiler_count = CICompilerCount;
- }
-}
-
-// Note: this policy is used ONLY if TieredCompilation is off.
-// compiler_count() behaves the following way:
-// - with TIERED build (with both COMPILER1 and COMPILER2 defined) it should return
-// zero for the c1 compilation levels in server compilation mode runs
-// and c2 compilation levels in client compilation mode runs.
-// - with COMPILER2 not defined it should return zero for c2 compilation levels.
-// - with COMPILER1 not defined it should return zero for c1 compilation levels.
-// - if neither is defined - always return zero.
-int SimpleCompPolicy::compiler_count(CompLevel comp_level) {
- assert(!TieredCompilation, "This policy should not be used with TieredCompilation");
- if (COMPILER2_PRESENT(is_server_compilation_mode_vm() && is_c2_compile(comp_level) ||)
- is_client_compilation_mode_vm() && is_c1_compile(comp_level)) {
- return _compiler_count;
- }
- return 0;
-}
-
-void SimpleCompPolicy::reset_counter_for_invocation_event(const methodHandle& m) {
- // Make sure invocation and backedge counter doesn't overflow again right away
- // as would be the case for native methods.
-
- // BUT also make sure the method doesn't look like it was never executed.
- // Set carry bit and reduce counter's value to min(count, CompileThreshold/2).
- MethodCounters* mcs = m->method_counters();
- assert(mcs != NULL, "MethodCounters cannot be NULL for profiling");
- mcs->invocation_counter()->set_carry();
- mcs->backedge_counter()->set_carry();
-
- assert(!m->was_never_executed(), "don't reset to 0 -- could be mistaken for never-executed");
-}
-
-void SimpleCompPolicy::reset_counter_for_back_branch_event(const methodHandle& m) {
- // Delay next back-branch event but pump up invocation counter to trigger
- // whole method compilation.
- MethodCounters* mcs = m->method_counters();
- assert(mcs != NULL, "MethodCounters cannot be NULL for profiling");
- InvocationCounter* i = mcs->invocation_counter();
- InvocationCounter* b = mcs->backedge_counter();
-
- // Don't set invocation_counter's value too low otherwise the method will
- // look like immature (ic < ~5300) which prevents the inlining based on
- // the type profiling.
- i->set(i->state(), CompileThreshold);
- // Don't reset counter too low - it is used to check if OSR method is ready.
- b->set(b->state(), CompileThreshold / 2);
-}
-
-//
-// CounterDecay
-//
-// Iterates through invocation counters and decrements them. This
-// is done at each safepoint.
-//
-class CounterDecay : public AllStatic {
- static jlong _last_timestamp;
- static void do_method(Method* m) {
- MethodCounters* mcs = m->method_counters();
- if (mcs != NULL) {
- mcs->invocation_counter()->decay();
- }
- }
-public:
- static void decay();
- static bool is_decay_needed() {
- return (os::javaTimeMillis() - _last_timestamp) > CounterDecayMinIntervalLength;
- }
-};
-
-jlong CounterDecay::_last_timestamp = 0;
-
-void CounterDecay::decay() {
- _last_timestamp = os::javaTimeMillis();
-
- // This operation is going to be performed only at the end of a safepoint
- // and hence GC's will not be going on, all Java mutators are suspended
- // at this point and hence SystemDictionary_lock is also not needed.
- assert(SafepointSynchronize::is_at_safepoint(), "can only be executed at a safepoint");
- size_t nclasses = ClassLoaderDataGraph::num_instance_classes();
- size_t classes_per_tick = nclasses * (CounterDecayMinIntervalLength * 1e-3 /
- CounterHalfLifeTime);
- for (size_t i = 0; i < classes_per_tick; i++) {
- InstanceKlass* k = ClassLoaderDataGraph::try_get_next_class();
- if (k != NULL) {
- k->methods_do(do_method);
- }
- }
-}
-
-// Called at the end of the safepoint
-void SimpleCompPolicy::do_safepoint_work() {
- if(UseCounterDecay && CounterDecay::is_decay_needed()) {
- CounterDecay::decay();
- }
-}
-
-void SimpleCompPolicy::reprofile(ScopeDesc* trap_scope, bool is_osr) {
- ScopeDesc* sd = trap_scope;
- MethodCounters* mcs;
- InvocationCounter* c;
- for (; !sd->is_top(); sd = sd->sender()) {
- mcs = sd->method()->method_counters();
- if (mcs != NULL) {
- // Reset ICs of inlined methods, since they can trigger compilations also.
- mcs->invocation_counter()->reset();
- }
- }
- mcs = sd->method()->method_counters();
- if (mcs != NULL) {
- c = mcs->invocation_counter();
- if (is_osr) {
- // It was an OSR method, so bump the count higher.
- c->set(c->state(), CompileThreshold);
- } else {
- c->reset();
- }
- mcs->backedge_counter()->reset();
- }
-}
-
-// This method can be called by any component of the runtime to notify the policy
-// that it's recommended to delay the compilation of this method.
-void SimpleCompPolicy::delay_compilation(Method* method) {
- MethodCounters* mcs = method->method_counters();
- if (mcs != NULL) {
- mcs->invocation_counter()->decay();
- mcs->backedge_counter()->decay();
- }
-}
-
-void SimpleCompPolicy::disable_compilation(Method* method) {
- MethodCounters* mcs = method->method_counters();
- if (mcs != NULL) {
- mcs->invocation_counter()->set_state(InvocationCounter::wait_for_nothing);
- mcs->backedge_counter()->set_state(InvocationCounter::wait_for_nothing);
- }
-}
-
-CompileTask* SimpleCompPolicy::select_task(CompileQueue* compile_queue) {
- return select_task_helper(compile_queue);
-}
-
-bool SimpleCompPolicy::is_mature(Method* method) {
- MethodData* mdo = method->method_data();
- assert(mdo != NULL, "Should be");
- uint current = mdo->mileage_of(method);
- uint initial = mdo->creation_mileage();
- if (current < initial)
- return true; // some sort of overflow
- uint target;
- if (ProfileMaturityPercentage <= 0)
- target = (uint) -ProfileMaturityPercentage; // absolute value
- else
- target = (uint)( (ProfileMaturityPercentage * CompileThreshold) / 100 );
- return (current >= initial + target);
-}
-
-nmethod* SimpleCompPolicy::event(const methodHandle& method, const methodHandle& inlinee, int branch_bci,
- int bci, CompLevel comp_level, CompiledMethod* nm, JavaThread* thread) {
- assert(comp_level == CompLevel_none, "This should be only called from the interpreter");
- NOT_PRODUCT(trace_frequency_counter_overflow(method, branch_bci, bci));
- if (JvmtiExport::can_post_interpreter_events() && thread->is_interp_only_mode()) {
- // If certain JVMTI events (e.g. frame pop event) are requested then the
- // thread is forced to remain in interpreted code. This is
- // implemented partly by a check in the run_compiled_code
- // section of the interpreter whether we should skip running
- // compiled code, and partly by skipping OSR compiles for
- // interpreted-only threads.
- if (bci != InvocationEntryBci) {
- reset_counter_for_back_branch_event(method);
- return NULL;
- }
- }
- if (ReplayCompiles) {
- // Don't trigger other compiles in testing mode
- if (bci == InvocationEntryBci) {
- reset_counter_for_invocation_event(method);
- } else {
- reset_counter_for_back_branch_event(method);
- }
- return NULL;
- }
-
- if (bci == InvocationEntryBci) {
- // when code cache is full, compilation gets switched off, UseCompiler
- // is set to false
- if (!method->has_compiled_code() && UseCompiler) {
- method_invocation_event(method, thread);
- } else {
- // Force counter overflow on method entry, even if no compilation
- // happened. (The method_invocation_event call does this also.)
- reset_counter_for_invocation_event(method);
- }
- // compilation at an invocation overflow no longer goes and retries test for
- // compiled method. We always run the loser of the race as interpreted.
- // so return NULL
- return NULL;
- } else {
- // counter overflow in a loop => try to do on-stack-replacement
- nmethod* osr_nm = method->lookup_osr_nmethod_for(bci, CompLevel_highest_tier, true);
- NOT_PRODUCT(trace_osr_request(method, osr_nm, bci));
- // when code cache is full, we should not compile any more...
- if (osr_nm == NULL && UseCompiler) {
- method_back_branch_event(method, bci, thread);
- osr_nm = method->lookup_osr_nmethod_for(bci, CompLevel_highest_tier, true);
- }
- if (osr_nm == NULL) {
- reset_counter_for_back_branch_event(method);
- return NULL;
- }
- return osr_nm;
- }
- return NULL;
-}
-
-#ifndef PRODUCT
-void SimpleCompPolicy::trace_frequency_counter_overflow(const methodHandle& m, int branch_bci, int bci) {
- if (TraceInvocationCounterOverflow) {
- MethodCounters* mcs = m->method_counters();
- assert(mcs != NULL, "MethodCounters cannot be NULL for profiling");
- InvocationCounter* ic = mcs->invocation_counter();
- InvocationCounter* bc = mcs->backedge_counter();
- ResourceMark rm;
- if (bci == InvocationEntryBci) {
- tty->print("comp-policy cntr ovfl @ %d in entry of ", bci);
- } else {
- tty->print("comp-policy cntr ovfl @ %d in loop of ", bci);
- }
- m->print_value();
- tty->cr();
- ic->print();
- bc->print();
- if (ProfileInterpreter) {
- if (bci != InvocationEntryBci) {
- MethodData* mdo = m->method_data();
- if (mdo != NULL) {
- ProfileData *pd = mdo->bci_to_data(branch_bci);
- if (pd == NULL) {
- tty->print_cr("back branch count = N/A (missing ProfileData)");
- } else {
- tty->print_cr("back branch count = %d", pd->as_JumpData()->taken());
- }
- }
- }
- }
- }
-}
-
-void SimpleCompPolicy::trace_osr_request(const methodHandle& method, nmethod* osr, int bci) {
- if (TraceOnStackReplacement) {
- ResourceMark rm;
- tty->print(osr != NULL ? "Reused OSR entry for " : "Requesting OSR entry for ");
- method->print_short_name(tty);
- tty->print_cr(" at bci %d", bci);
- }
-}
-#endif // !PRODUCT
-
-void SimpleCompPolicy::method_invocation_event(const methodHandle& m, JavaThread* thread) {
- const int comp_level = CompLevel_highest_tier;
- const int hot_count = m->invocation_count();
- reset_counter_for_invocation_event(m);
-
- if (is_compilation_enabled() && can_be_compiled(m, comp_level)) {
- CompiledMethod* nm = m->code();
- if (nm == NULL ) {
- CompileBroker::compile_method(m, InvocationEntryBci, comp_level, m, hot_count, CompileTask::Reason_InvocationCount, thread);
- }
- }
-}
-
-void SimpleCompPolicy::method_back_branch_event(const methodHandle& m, int bci, JavaThread* thread) {
- const int comp_level = CompLevel_highest_tier;
- const int hot_count = m->backedge_count();
-
- if (is_compilation_enabled() && can_be_osr_compiled(m, comp_level)) {
- CompileBroker::compile_method(m, bci, comp_level, m, hot_count, CompileTask::Reason_BackedgeCount, thread);
- NOT_PRODUCT(trace_osr_completion(m->lookup_osr_nmethod_for(bci, comp_level, true));)
- }
-}