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deoptimization.cpp
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deoptimization.cpp
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/*
* Copyright (c) 1997, 2021, 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 "jvm.h"
#include "classfile/javaClasses.inline.hpp"
#include "classfile/symbolTable.hpp"
#include "classfile/systemDictionary.hpp"
#include "classfile/vmClasses.hpp"
#include "code/codeCache.hpp"
#include "code/debugInfoRec.hpp"
#include "code/nmethod.hpp"
#include "code/pcDesc.hpp"
#include "code/scopeDesc.hpp"
#include "compiler/compilationPolicy.hpp"
#include "interpreter/bytecode.hpp"
#include "interpreter/interpreter.hpp"
#include "interpreter/oopMapCache.hpp"
#include "memory/allocation.inline.hpp"
#include "memory/oopFactory.hpp"
#include "memory/resourceArea.hpp"
#include "memory/universe.hpp"
#include "oops/constantPool.hpp"
#include "oops/method.hpp"
#include "oops/objArrayKlass.hpp"
#include "oops/objArrayOop.inline.hpp"
#include "oops/oop.inline.hpp"
#include "oops/fieldStreams.inline.hpp"
#include "oops/typeArrayOop.inline.hpp"
#include "oops/verifyOopClosure.hpp"
#include "prims/jvmtiDeferredUpdates.hpp"
#include "prims/jvmtiExport.hpp"
#include "prims/jvmtiThreadState.hpp"
#include "prims/vectorSupport.hpp"
#include "prims/methodHandles.hpp"
#include "runtime/atomic.hpp"
#include "runtime/biasedLocking.hpp"
#include "runtime/deoptimization.hpp"
#include "runtime/escapeBarrier.hpp"
#include "runtime/fieldDescriptor.hpp"
#include "runtime/fieldDescriptor.inline.hpp"
#include "runtime/frame.inline.hpp"
#include "runtime/handles.inline.hpp"
#include "runtime/interfaceSupport.inline.hpp"
#include "runtime/jniHandles.inline.hpp"
#include "runtime/keepStackGCProcessed.hpp"
#include "runtime/objectMonitor.inline.hpp"
#include "runtime/osThread.hpp"
#include "runtime/safepointVerifiers.hpp"
#include "runtime/sharedRuntime.hpp"
#include "runtime/signature.hpp"
#include "runtime/stackWatermarkSet.hpp"
#include "runtime/stubRoutines.hpp"
#include "runtime/thread.hpp"
#include "runtime/threadSMR.hpp"
#include "runtime/vframe.hpp"
#include "runtime/vframeArray.hpp"
#include "runtime/vframe_hp.hpp"
#include "utilities/events.hpp"
#include "utilities/macros.hpp"
#include "utilities/preserveException.hpp"
#include "utilities/xmlstream.hpp"
#if INCLUDE_JFR
#include "jfr/jfrEvents.hpp"
#include "jfr/metadata/jfrSerializer.hpp"
#endif
bool DeoptimizationMarker::_is_active = false;
Deoptimization::UnrollBlock::UnrollBlock(int size_of_deoptimized_frame,
int caller_adjustment,
int caller_actual_parameters,
int number_of_frames,
intptr_t* frame_sizes,
address* frame_pcs,
BasicType return_type,
int exec_mode) {
_size_of_deoptimized_frame = size_of_deoptimized_frame;
_caller_adjustment = caller_adjustment;
_caller_actual_parameters = caller_actual_parameters;
_number_of_frames = number_of_frames;
_frame_sizes = frame_sizes;
_frame_pcs = frame_pcs;
_register_block = NEW_C_HEAP_ARRAY(intptr_t, RegisterMap::reg_count * 2, mtCompiler);
_return_type = return_type;
_initial_info = 0;
// PD (x86 only)
_counter_temp = 0;
_unpack_kind = exec_mode;
_sender_sp_temp = 0;
_total_frame_sizes = size_of_frames();
assert(exec_mode >= 0 && exec_mode < Unpack_LIMIT, "Unexpected exec_mode");
}
Deoptimization::UnrollBlock::~UnrollBlock() {
FREE_C_HEAP_ARRAY(intptr_t, _frame_sizes);
FREE_C_HEAP_ARRAY(intptr_t, _frame_pcs);
FREE_C_HEAP_ARRAY(intptr_t, _register_block);
}
intptr_t* Deoptimization::UnrollBlock::value_addr_at(int register_number) const {
assert(register_number < RegisterMap::reg_count, "checking register number");
return &_register_block[register_number * 2];
}
int Deoptimization::UnrollBlock::size_of_frames() const {
// Acount first for the adjustment of the initial frame
int result = _caller_adjustment;
for (int index = 0; index < number_of_frames(); index++) {
result += frame_sizes()[index];
}
return result;
}
void Deoptimization::UnrollBlock::print() {
ttyLocker ttyl;
tty->print_cr("UnrollBlock");
tty->print_cr(" size_of_deoptimized_frame = %d", _size_of_deoptimized_frame);
tty->print( " frame_sizes: ");
for (int index = 0; index < number_of_frames(); index++) {
tty->print(INTX_FORMAT " ", frame_sizes()[index]);
}
tty->cr();
}
// In order to make fetch_unroll_info work properly with escape
// analysis, the method was changed from JRT_LEAF to JRT_BLOCK_ENTRY.
// The actual reallocation of previously eliminated objects occurs in realloc_objects,
// which is called from the method fetch_unroll_info_helper below.
JRT_BLOCK_ENTRY(Deoptimization::UnrollBlock*, Deoptimization::fetch_unroll_info(JavaThread* thread, int exec_mode))
// fetch_unroll_info() is called at the beginning of the deoptimization
// handler. Note this fact before we start generating temporary frames
// that can confuse an asynchronous stack walker. This counter is
// decremented at the end of unpack_frames().
if (TraceDeoptimization) {
tty->print_cr("Deoptimizing thread " INTPTR_FORMAT, p2i(thread));
}
thread->inc_in_deopt_handler();
if (exec_mode == Unpack_exception) {
// When we get here, a callee has thrown an exception into a deoptimized
// frame. That throw might have deferred stack watermark checking until
// after unwinding. So we deal with such deferred requests here.
StackWatermarkSet::after_unwind(thread);
}
return fetch_unroll_info_helper(thread, exec_mode);
JRT_END
#if COMPILER2_OR_JVMCI
static bool eliminate_allocations(JavaThread* thread, int exec_mode, CompiledMethod* compiled_method,
frame& deoptee, RegisterMap& map, GrowableArray<compiledVFrame*>* chunk,
bool& deoptimized_objects) {
bool realloc_failures = false;
assert (chunk->at(0)->scope() != NULL,"expect only compiled java frames");
JavaThread* deoptee_thread = chunk->at(0)->thread();
assert(exec_mode == Deoptimization::Unpack_none || (deoptee_thread == thread),
"a frame can only be deoptimized by the owner thread");
GrowableArray<ScopeValue*>* objects = chunk->at(0)->scope()->objects();
// The flag return_oop() indicates call sites which return oop
// in compiled code. Such sites include java method calls,
// runtime calls (for example, used to allocate new objects/arrays
// on slow code path) and any other calls generated in compiled code.
// It is not guaranteed that we can get such information here only
// by analyzing bytecode in deoptimized frames. This is why this flag
// is set during method compilation (see Compile::Process_OopMap_Node()).
// If the previous frame was popped or if we are dispatching an exception,
// we don't have an oop result.
bool save_oop_result = chunk->at(0)->scope()->return_oop() && !thread->popframe_forcing_deopt_reexecution() && (exec_mode == Deoptimization::Unpack_deopt);
Handle return_value;
if (save_oop_result) {
// Reallocation may trigger GC. If deoptimization happened on return from
// call which returns oop we need to save it since it is not in oopmap.
oop result = deoptee.saved_oop_result(&map);
assert(oopDesc::is_oop_or_null(result), "must be oop");
return_value = Handle(thread, result);
assert(Universe::heap()->is_in_or_null(result), "must be heap pointer");
if (TraceDeoptimization) {
ttyLocker ttyl;
tty->print_cr("SAVED OOP RESULT " INTPTR_FORMAT " in thread " INTPTR_FORMAT, p2i(result), p2i(thread));
}
}
if (objects != NULL) {
if (exec_mode == Deoptimization::Unpack_none) {
assert(thread->thread_state() == _thread_in_vm, "assumption");
Thread* THREAD = thread;
// Clear pending OOM if reallocation fails and return true indicating allocation failure
realloc_failures = Deoptimization::realloc_objects(thread, &deoptee, &map, objects, CHECK_AND_CLEAR_(true));
deoptimized_objects = true;
} else {
JRT_BLOCK
realloc_failures = Deoptimization::realloc_objects(thread, &deoptee, &map, objects, THREAD);
JRT_END
}
bool skip_internal = (compiled_method != NULL) && !compiled_method->is_compiled_by_jvmci();
Deoptimization::reassign_fields(&deoptee, &map, objects, realloc_failures, skip_internal);
#ifndef PRODUCT
if (TraceDeoptimization) {
ttyLocker ttyl;
tty->print_cr("REALLOC OBJECTS in thread " INTPTR_FORMAT, p2i(deoptee_thread));
Deoptimization::print_objects(objects, realloc_failures);
}
#endif
}
if (save_oop_result) {
// Restore result.
deoptee.set_saved_oop_result(&map, return_value());
}
return realloc_failures;
}
static void eliminate_locks(JavaThread* thread, GrowableArray<compiledVFrame*>* chunk, bool realloc_failures,
frame& deoptee, int exec_mode, bool& deoptimized_objects) {
JavaThread* deoptee_thread = chunk->at(0)->thread();
assert(!EscapeBarrier::objs_are_deoptimized(deoptee_thread, deoptee.id()), "must relock just once");
assert(thread == Thread::current(), "should be");
HandleMark hm(thread);
#ifndef PRODUCT
bool first = true;
#endif
for (int i = 0; i < chunk->length(); i++) {
compiledVFrame* cvf = chunk->at(i);
assert (cvf->scope() != NULL,"expect only compiled java frames");
GrowableArray<MonitorInfo*>* monitors = cvf->monitors();
if (monitors->is_nonempty()) {
bool relocked = Deoptimization::relock_objects(thread, monitors, deoptee_thread, deoptee,
exec_mode, realloc_failures);
deoptimized_objects = deoptimized_objects || relocked;
#ifndef PRODUCT
if (PrintDeoptimizationDetails) {
ttyLocker ttyl;
for (int j = 0; j < monitors->length(); j++) {
MonitorInfo* mi = monitors->at(j);
if (mi->eliminated()) {
if (first) {
first = false;
tty->print_cr("RELOCK OBJECTS in thread " INTPTR_FORMAT, p2i(thread));
}
if (exec_mode == Deoptimization::Unpack_none) {
ObjectMonitor* monitor = deoptee_thread->current_waiting_monitor();
if (monitor != NULL && (oop)monitor->object() == mi->owner()) {
tty->print_cr(" object <" INTPTR_FORMAT "> DEFERRED relocking after wait", p2i(mi->owner()));
continue;
}
}
if (mi->owner_is_scalar_replaced()) {
Klass* k = java_lang_Class::as_Klass(mi->owner_klass());
tty->print_cr(" failed reallocation for klass %s", k->external_name());
} else {
tty->print_cr(" object <" INTPTR_FORMAT "> locked", p2i(mi->owner()));
}
}
}
}
#endif // !PRODUCT
}
}
}
// Deoptimize objects, that is reallocate and relock them, just before they escape through JVMTI.
// The given vframes cover one physical frame.
bool Deoptimization::deoptimize_objects_internal(JavaThread* thread, GrowableArray<compiledVFrame*>* chunk,
bool& realloc_failures) {
frame deoptee = chunk->at(0)->fr();
JavaThread* deoptee_thread = chunk->at(0)->thread();
CompiledMethod* cm = deoptee.cb()->as_compiled_method_or_null();
RegisterMap map(chunk->at(0)->register_map());
bool deoptimized_objects = false;
bool const jvmci_enabled = JVMCI_ONLY(UseJVMCICompiler) NOT_JVMCI(false);
// Reallocate the non-escaping objects and restore their fields.
if (jvmci_enabled COMPILER2_PRESENT(|| (DoEscapeAnalysis && EliminateAllocations))) {
realloc_failures = eliminate_allocations(thread, Unpack_none, cm, deoptee, map, chunk, deoptimized_objects);
}
// Revoke biases of objects with eliminated locks in the given frame.
Deoptimization::revoke_for_object_deoptimization(deoptee_thread, deoptee, &map, thread);
// MonitorInfo structures used in eliminate_locks are not GC safe.
NoSafepointVerifier no_safepoint;
// Now relock objects if synchronization on them was eliminated.
if (jvmci_enabled COMPILER2_PRESENT(|| ((DoEscapeAnalysis || EliminateNestedLocks) && EliminateLocks))) {
eliminate_locks(thread, chunk, realloc_failures, deoptee, Unpack_none, deoptimized_objects);
}
return deoptimized_objects;
}
#endif // COMPILER2_OR_JVMCI
// This is factored, since it is both called from a JRT_LEAF (deoptimization) and a JRT_ENTRY (uncommon_trap)
Deoptimization::UnrollBlock* Deoptimization::fetch_unroll_info_helper(JavaThread* thread, int exec_mode) {
// When we get here we are about to unwind the deoptee frame. In order to
// catch not yet safe to use frames, the following stack watermark barrier
// poll will make such frames safe to use.
StackWatermarkSet::before_unwind(thread);
// Note: there is a safepoint safety issue here. No matter whether we enter
// via vanilla deopt or uncommon trap we MUST NOT stop at a safepoint once
// the vframeArray is created.
//
// Allocate our special deoptimization ResourceMark
DeoptResourceMark* dmark = new DeoptResourceMark(thread);
assert(thread->deopt_mark() == NULL, "Pending deopt!");
thread->set_deopt_mark(dmark);
frame stub_frame = thread->last_frame(); // Makes stack walkable as side effect
RegisterMap map(thread, true);
RegisterMap dummy_map(thread, false);
// Now get the deoptee with a valid map
frame deoptee = stub_frame.sender(&map);
// Set the deoptee nmethod
assert(thread->deopt_compiled_method() == NULL, "Pending deopt!");
CompiledMethod* cm = deoptee.cb()->as_compiled_method_or_null();
thread->set_deopt_compiled_method(cm);
if (VerifyStack) {
thread->validate_frame_layout();
}
// Create a growable array of VFrames where each VFrame represents an inlined
// Java frame. This storage is allocated with the usual system arena.
assert(deoptee.is_compiled_frame(), "Wrong frame type");
GrowableArray<compiledVFrame*>* chunk = new GrowableArray<compiledVFrame*>(10);
vframe* vf = vframe::new_vframe(&deoptee, &map, thread);
while (!vf->is_top()) {
assert(vf->is_compiled_frame(), "Wrong frame type");
chunk->push(compiledVFrame::cast(vf));
vf = vf->sender();
}
assert(vf->is_compiled_frame(), "Wrong frame type");
chunk->push(compiledVFrame::cast(vf));
bool realloc_failures = false;
#if COMPILER2_OR_JVMCI
#if INCLUDE_JVMCI
bool jvmci_enabled = true;
#else
bool jvmci_enabled = false;
#endif
// Reallocate the non-escaping objects and restore their fields. Then
// relock objects if synchronization on them was eliminated.
if (jvmci_enabled COMPILER2_PRESENT( || (DoEscapeAnalysis && EliminateAllocations) )) {
bool unused;
realloc_failures = eliminate_allocations(thread, exec_mode, cm, deoptee, map, chunk, unused);
}
#endif // COMPILER2_OR_JVMCI
// Revoke biases, done with in java state.
// No safepoints allowed after this
revoke_from_deopt_handler(thread, deoptee, &map);
// Ensure that no safepoint is taken after pointers have been stored
// in fields of rematerialized objects. If a safepoint occurs from here on
// out the java state residing in the vframeArray will be missed.
// Locks may be rebaised in a safepoint.
NoSafepointVerifier no_safepoint;
#if COMPILER2_OR_JVMCI
if ((jvmci_enabled COMPILER2_PRESENT( || ((DoEscapeAnalysis || EliminateNestedLocks) && EliminateLocks) ))
&& !EscapeBarrier::objs_are_deoptimized(thread, deoptee.id())) {
bool unused;
eliminate_locks(thread, chunk, realloc_failures, deoptee, exec_mode, unused);
}
#endif // COMPILER2_OR_JVMCI
ScopeDesc* trap_scope = chunk->at(0)->scope();
Handle exceptionObject;
if (trap_scope->rethrow_exception()) {
if (PrintDeoptimizationDetails) {
tty->print_cr("Exception to be rethrown in the interpreter for method %s::%s at bci %d", trap_scope->method()->method_holder()->name()->as_C_string(), trap_scope->method()->name()->as_C_string(), trap_scope->bci());
}
GrowableArray<ScopeValue*>* expressions = trap_scope->expressions();
guarantee(expressions != NULL && expressions->length() > 0, "must have exception to throw");
ScopeValue* topOfStack = expressions->top();
exceptionObject = StackValue::create_stack_value(&deoptee, &map, topOfStack)->get_obj();
guarantee(exceptionObject() != NULL, "exception oop can not be null");
}
vframeArray* array = create_vframeArray(thread, deoptee, &map, chunk, realloc_failures);
#if COMPILER2_OR_JVMCI
if (realloc_failures) {
pop_frames_failed_reallocs(thread, array);
}
#endif
assert(thread->vframe_array_head() == NULL, "Pending deopt!");
thread->set_vframe_array_head(array);
// Now that the vframeArray has been created if we have any deferred local writes
// added by jvmti then we can free up that structure as the data is now in the
// vframeArray
JvmtiDeferredUpdates::delete_updates_for_frame(thread, array->original().id());
// Compute the caller frame based on the sender sp of stub_frame and stored frame sizes info.
CodeBlob* cb = stub_frame.cb();
// Verify we have the right vframeArray
assert(cb->frame_size() >= 0, "Unexpected frame size");
intptr_t* unpack_sp = stub_frame.sp() + cb->frame_size();
// If the deopt call site is a MethodHandle invoke call site we have
// to adjust the unpack_sp.
nmethod* deoptee_nm = deoptee.cb()->as_nmethod_or_null();
if (deoptee_nm != NULL && deoptee_nm->is_method_handle_return(deoptee.pc()))
unpack_sp = deoptee.unextended_sp();
#ifdef ASSERT
assert(cb->is_deoptimization_stub() ||
cb->is_uncommon_trap_stub() ||
strcmp("Stub<DeoptimizationStub.deoptimizationHandler>", cb->name()) == 0 ||
strcmp("Stub<UncommonTrapStub.uncommonTrapHandler>", cb->name()) == 0,
"unexpected code blob: %s", cb->name());
#endif
// This is a guarantee instead of an assert because if vframe doesn't match
// we will unpack the wrong deoptimized frame and wind up in strange places
// where it will be very difficult to figure out what went wrong. Better
// to die an early death here than some very obscure death later when the
// trail is cold.
// Note: on ia64 this guarantee can be fooled by frames with no memory stack
// in that it will fail to detect a problem when there is one. This needs
// more work in tiger timeframe.
guarantee(array->unextended_sp() == unpack_sp, "vframe_array_head must contain the vframeArray to unpack");
int number_of_frames = array->frames();
// Compute the vframes' sizes. Note that frame_sizes[] entries are ordered from outermost to innermost
// virtual activation, which is the reverse of the elements in the vframes array.
intptr_t* frame_sizes = NEW_C_HEAP_ARRAY(intptr_t, number_of_frames, mtCompiler);
// +1 because we always have an interpreter return address for the final slot.
address* frame_pcs = NEW_C_HEAP_ARRAY(address, number_of_frames + 1, mtCompiler);
int popframe_extra_args = 0;
// Create an interpreter return address for the stub to use as its return
// address so the skeletal frames are perfectly walkable
frame_pcs[number_of_frames] = Interpreter::deopt_entry(vtos, 0);
// PopFrame requires that the preserved incoming arguments from the recently-popped topmost
// activation be put back on the expression stack of the caller for reexecution
if (JvmtiExport::can_pop_frame() && thread->popframe_forcing_deopt_reexecution()) {
popframe_extra_args = in_words(thread->popframe_preserved_args_size_in_words());
}
// Find the current pc for sender of the deoptee. Since the sender may have been deoptimized
// itself since the deoptee vframeArray was created we must get a fresh value of the pc rather
// than simply use array->sender.pc(). This requires us to walk the current set of frames
//
frame deopt_sender = stub_frame.sender(&dummy_map); // First is the deoptee frame
deopt_sender = deopt_sender.sender(&dummy_map); // Now deoptee caller
// It's possible that the number of parameters at the call site is
// different than number of arguments in the callee when method
// handles are used. If the caller is interpreted get the real
// value so that the proper amount of space can be added to it's
// frame.
bool caller_was_method_handle = false;
if (deopt_sender.is_interpreted_frame()) {
methodHandle method(thread, deopt_sender.interpreter_frame_method());
Bytecode_invoke cur = Bytecode_invoke_check(method, deopt_sender.interpreter_frame_bci());
if (cur.is_invokedynamic() || cur.is_invokehandle()) {
// Method handle invokes may involve fairly arbitrary chains of
// calls so it's impossible to know how much actual space the
// caller has for locals.
caller_was_method_handle = true;
}
}
//
// frame_sizes/frame_pcs[0] oldest frame (int or c2i)
// frame_sizes/frame_pcs[1] next oldest frame (int)
// frame_sizes/frame_pcs[n] youngest frame (int)
//
// Now a pc in frame_pcs is actually the return address to the frame's caller (a frame
// owns the space for the return address to it's caller). Confusing ain't it.
//
// The vframe array can address vframes with indices running from
// 0.._frames-1. Index 0 is the youngest frame and _frame - 1 is the oldest (root) frame.
// When we create the skeletal frames we need the oldest frame to be in the zero slot
// in the frame_sizes/frame_pcs so the assembly code can do a trivial walk.
// so things look a little strange in this loop.
//
int callee_parameters = 0;
int callee_locals = 0;
for (int index = 0; index < array->frames(); index++ ) {
// frame[number_of_frames - 1 ] = on_stack_size(youngest)
// frame[number_of_frames - 2 ] = on_stack_size(sender(youngest))
// frame[number_of_frames - 3 ] = on_stack_size(sender(sender(youngest)))
frame_sizes[number_of_frames - 1 - index] = BytesPerWord * array->element(index)->on_stack_size(callee_parameters,
callee_locals,
index == 0,
popframe_extra_args);
// This pc doesn't have to be perfect just good enough to identify the frame
// as interpreted so the skeleton frame will be walkable
// The correct pc will be set when the skeleton frame is completely filled out
// The final pc we store in the loop is wrong and will be overwritten below
frame_pcs[number_of_frames - 1 - index ] = Interpreter::deopt_entry(vtos, 0) - frame::pc_return_offset;
callee_parameters = array->element(index)->method()->size_of_parameters();
callee_locals = array->element(index)->method()->max_locals();
popframe_extra_args = 0;
}
// Compute whether the root vframe returns a float or double value.
BasicType return_type;
{
methodHandle method(thread, array->element(0)->method());
Bytecode_invoke invoke = Bytecode_invoke_check(method, array->element(0)->bci());
return_type = invoke.is_valid() ? invoke.result_type() : T_ILLEGAL;
}
// Compute information for handling adapters and adjusting the frame size of the caller.
int caller_adjustment = 0;
// Compute the amount the oldest interpreter frame will have to adjust
// its caller's stack by. If the caller is a compiled frame then
// we pretend that the callee has no parameters so that the
// extension counts for the full amount of locals and not just
// locals-parms. This is because without a c2i adapter the parm
// area as created by the compiled frame will not be usable by
// the interpreter. (Depending on the calling convention there
// may not even be enough space).
// QQQ I'd rather see this pushed down into last_frame_adjust
// and have it take the sender (aka caller).
if (deopt_sender.is_compiled_frame() || caller_was_method_handle) {
caller_adjustment = last_frame_adjust(0, callee_locals);
} else if (callee_locals > callee_parameters) {
// The caller frame may need extending to accommodate
// non-parameter locals of the first unpacked interpreted frame.
// Compute that adjustment.
caller_adjustment = last_frame_adjust(callee_parameters, callee_locals);
}
// If the sender is deoptimized the we must retrieve the address of the handler
// since the frame will "magically" show the original pc before the deopt
// and we'd undo the deopt.
frame_pcs[0] = deopt_sender.raw_pc();
assert(CodeCache::find_blob_unsafe(frame_pcs[0]) != NULL, "bad pc");
#if INCLUDE_JVMCI
if (exceptionObject() != NULL) {
thread->set_exception_oop(exceptionObject());
exec_mode = Unpack_exception;
}
#endif
if (thread->frames_to_pop_failed_realloc() > 0 && exec_mode != Unpack_uncommon_trap) {
assert(thread->has_pending_exception(), "should have thrown OOME");
thread->set_exception_oop(thread->pending_exception());
thread->clear_pending_exception();
exec_mode = Unpack_exception;
}
#if INCLUDE_JVMCI
if (thread->frames_to_pop_failed_realloc() > 0) {
thread->set_pending_monitorenter(false);
}
#endif
UnrollBlock* info = new UnrollBlock(array->frame_size() * BytesPerWord,
caller_adjustment * BytesPerWord,
caller_was_method_handle ? 0 : callee_parameters,
number_of_frames,
frame_sizes,
frame_pcs,
return_type,
exec_mode);
// On some platforms, we need a way to pass some platform dependent
// information to the unpacking code so the skeletal frames come out
// correct (initial fp value, unextended sp, ...)
info->set_initial_info((intptr_t) array->sender().initial_deoptimization_info());
if (array->frames() > 1) {
if (VerifyStack && TraceDeoptimization) {
ttyLocker ttyl;
tty->print_cr("Deoptimizing method containing inlining");
}
}
array->set_unroll_block(info);
return info;
}
// Called to cleanup deoptimization data structures in normal case
// after unpacking to stack and when stack overflow error occurs
void Deoptimization::cleanup_deopt_info(JavaThread *thread,
vframeArray *array) {
// Get array if coming from exception
if (array == NULL) {
array = thread->vframe_array_head();
}
thread->set_vframe_array_head(NULL);
// Free the previous UnrollBlock
vframeArray* old_array = thread->vframe_array_last();
thread->set_vframe_array_last(array);
if (old_array != NULL) {
UnrollBlock* old_info = old_array->unroll_block();
old_array->set_unroll_block(NULL);
delete old_info;
delete old_array;
}
// Deallocate any resource creating in this routine and any ResourceObjs allocated
// inside the vframeArray (StackValueCollections)
delete thread->deopt_mark();
thread->set_deopt_mark(NULL);
thread->set_deopt_compiled_method(NULL);
if (JvmtiExport::can_pop_frame()) {
// Regardless of whether we entered this routine with the pending
// popframe condition bit set, we should always clear it now
thread->clear_popframe_condition();
}
// unpack_frames() is called at the end of the deoptimization handler
// and (in C2) at the end of the uncommon trap handler. Note this fact
// so that an asynchronous stack walker can work again. This counter is
// incremented at the beginning of fetch_unroll_info() and (in C2) at
// the beginning of uncommon_trap().
thread->dec_in_deopt_handler();
}
// Moved from cpu directories because none of the cpus has callee save values.
// If a cpu implements callee save values, move this to deoptimization_<cpu>.cpp.
void Deoptimization::unwind_callee_save_values(frame* f, vframeArray* vframe_array) {
// This code is sort of the equivalent of C2IAdapter::setup_stack_frame back in
// the days we had adapter frames. When we deoptimize a situation where a
// compiled caller calls a compiled caller will have registers it expects
// to survive the call to the callee. If we deoptimize the callee the only
// way we can restore these registers is to have the oldest interpreter
// frame that we create restore these values. That is what this routine
// will accomplish.
// At the moment we have modified c2 to not have any callee save registers
// so this problem does not exist and this routine is just a place holder.
assert(f->is_interpreted_frame(), "must be interpreted");
}
// Return BasicType of value being returned
JRT_LEAF(BasicType, Deoptimization::unpack_frames(JavaThread* thread, int exec_mode))
// We are already active in the special DeoptResourceMark any ResourceObj's we
// allocate will be freed at the end of the routine.
// JRT_LEAF methods don't normally allocate handles and there is a
// NoHandleMark to enforce that. It is actually safe to use Handles
// in a JRT_LEAF method, and sometimes desirable, but to do so we
// must use ResetNoHandleMark to bypass the NoHandleMark, and
// then use a HandleMark to ensure any Handles we do create are
// cleaned up in this scope.
ResetNoHandleMark rnhm;
HandleMark hm(thread);
frame stub_frame = thread->last_frame();
// Since the frame to unpack is the top frame of this thread, the vframe_array_head
// must point to the vframeArray for the unpack frame.
vframeArray* array = thread->vframe_array_head();
#ifndef PRODUCT
if (TraceDeoptimization) {
ttyLocker ttyl;
tty->print_cr("DEOPT UNPACKING thread " INTPTR_FORMAT " vframeArray " INTPTR_FORMAT " mode %d",
p2i(thread), p2i(array), exec_mode);
}
#endif
Events::log_deopt_message(thread, "DEOPT UNPACKING pc=" INTPTR_FORMAT " sp=" INTPTR_FORMAT " mode %d",
p2i(stub_frame.pc()), p2i(stub_frame.sp()), exec_mode);
UnrollBlock* info = array->unroll_block();
// We set the last_Java frame. But the stack isn't really parsable here. So we
// clear it to make sure JFR understands not to try and walk stacks from events
// in here.
intptr_t* sp = thread->frame_anchor()->last_Java_sp();
thread->frame_anchor()->set_last_Java_sp(NULL);
// Unpack the interpreter frames and any adapter frame (c2 only) we might create.
array->unpack_to_stack(stub_frame, exec_mode, info->caller_actual_parameters());
thread->frame_anchor()->set_last_Java_sp(sp);
BasicType bt = info->return_type();
// If we have an exception pending, claim that the return type is an oop
// so the deopt_blob does not overwrite the exception_oop.
if (exec_mode == Unpack_exception)
bt = T_OBJECT;
// Cleanup thread deopt data
cleanup_deopt_info(thread, array);
#ifndef PRODUCT
if (VerifyStack) {
ResourceMark res_mark;
// Clear pending exception to not break verification code (restored afterwards)
PreserveExceptionMark pm(thread);
thread->validate_frame_layout();
// Verify that the just-unpacked frames match the interpreter's
// notions of expression stack and locals
vframeArray* cur_array = thread->vframe_array_last();
RegisterMap rm(thread, false);
rm.set_include_argument_oops(false);
bool is_top_frame = true;
int callee_size_of_parameters = 0;
int callee_max_locals = 0;
for (int i = 0; i < cur_array->frames(); i++) {
vframeArrayElement* el = cur_array->element(i);
frame* iframe = el->iframe();
guarantee(iframe->is_interpreted_frame(), "Wrong frame type");
// Get the oop map for this bci
InterpreterOopMap mask;
int cur_invoke_parameter_size = 0;
bool try_next_mask = false;
int next_mask_expression_stack_size = -1;
int top_frame_expression_stack_adjustment = 0;
methodHandle mh(thread, iframe->interpreter_frame_method());
OopMapCache::compute_one_oop_map(mh, iframe->interpreter_frame_bci(), &mask);
BytecodeStream str(mh, iframe->interpreter_frame_bci());
int max_bci = mh->code_size();
// Get to the next bytecode if possible
assert(str.bci() < max_bci, "bci in interpreter frame out of bounds");
// Check to see if we can grab the number of outgoing arguments
// at an uncommon trap for an invoke (where the compiler
// generates debug info before the invoke has executed)
Bytecodes::Code cur_code = str.next();
if (Bytecodes::is_invoke(cur_code)) {
Bytecode_invoke invoke(mh, iframe->interpreter_frame_bci());
cur_invoke_parameter_size = invoke.size_of_parameters();
if (i != 0 && !invoke.is_invokedynamic() && MethodHandles::has_member_arg(invoke.klass(), invoke.name())) {
callee_size_of_parameters++;
}
}
if (str.bci() < max_bci) {
Bytecodes::Code next_code = str.next();
if (next_code >= 0) {
// The interpreter oop map generator reports results before
// the current bytecode has executed except in the case of
// calls. It seems to be hard to tell whether the compiler
// has emitted debug information matching the "state before"
// a given bytecode or the state after, so we try both
if (!Bytecodes::is_invoke(cur_code) && cur_code != Bytecodes::_athrow) {
// Get expression stack size for the next bytecode
InterpreterOopMap next_mask;
OopMapCache::compute_one_oop_map(mh, str.bci(), &next_mask);
next_mask_expression_stack_size = next_mask.expression_stack_size();
if (Bytecodes::is_invoke(next_code)) {
Bytecode_invoke invoke(mh, str.bci());
next_mask_expression_stack_size += invoke.size_of_parameters();
}
// Need to subtract off the size of the result type of
// the bytecode because this is not described in the
// debug info but returned to the interpreter in the TOS
// caching register
BasicType bytecode_result_type = Bytecodes::result_type(cur_code);
if (bytecode_result_type != T_ILLEGAL) {
top_frame_expression_stack_adjustment = type2size[bytecode_result_type];
}
assert(top_frame_expression_stack_adjustment >= 0, "stack adjustment must be positive");
try_next_mask = true;
}
}
}
// Verify stack depth and oops in frame
// This assertion may be dependent on the platform we're running on and may need modification (tested on x86 and sparc)
if (!(
/* SPARC */
(iframe->interpreter_frame_expression_stack_size() == mask.expression_stack_size() + callee_size_of_parameters) ||
/* x86 */
(iframe->interpreter_frame_expression_stack_size() == mask.expression_stack_size() + callee_max_locals) ||
(try_next_mask &&
(iframe->interpreter_frame_expression_stack_size() == (next_mask_expression_stack_size -
top_frame_expression_stack_adjustment))) ||
(is_top_frame && (exec_mode == Unpack_exception) && iframe->interpreter_frame_expression_stack_size() == 0) ||
(is_top_frame && (exec_mode == Unpack_uncommon_trap || exec_mode == Unpack_reexecute || el->should_reexecute()) &&
(iframe->interpreter_frame_expression_stack_size() == mask.expression_stack_size() + cur_invoke_parameter_size))
)) {
{
ttyLocker ttyl;
// Print out some information that will help us debug the problem
tty->print_cr("Wrong number of expression stack elements during deoptimization");
tty->print_cr(" Error occurred while verifying frame %d (0..%d, 0 is topmost)", i, cur_array->frames() - 1);
tty->print_cr(" Fabricated interpreter frame had %d expression stack elements",
iframe->interpreter_frame_expression_stack_size());
tty->print_cr(" Interpreter oop map had %d expression stack elements", mask.expression_stack_size());
tty->print_cr(" try_next_mask = %d", try_next_mask);
tty->print_cr(" next_mask_expression_stack_size = %d", next_mask_expression_stack_size);
tty->print_cr(" callee_size_of_parameters = %d", callee_size_of_parameters);
tty->print_cr(" callee_max_locals = %d", callee_max_locals);
tty->print_cr(" top_frame_expression_stack_adjustment = %d", top_frame_expression_stack_adjustment);
tty->print_cr(" exec_mode = %d", exec_mode);
tty->print_cr(" cur_invoke_parameter_size = %d", cur_invoke_parameter_size);
tty->print_cr(" Thread = " INTPTR_FORMAT ", thread ID = %d", p2i(thread), thread->osthread()->thread_id());
tty->print_cr(" Interpreted frames:");
for (int k = 0; k < cur_array->frames(); k++) {
vframeArrayElement* el = cur_array->element(k);
tty->print_cr(" %s (bci %d)", el->method()->name_and_sig_as_C_string(), el->bci());
}
cur_array->print_on_2(tty);
} // release tty lock before calling guarantee
guarantee(false, "wrong number of expression stack elements during deopt");
}
VerifyOopClosure verify;
iframe->oops_interpreted_do(&verify, &rm, false);
callee_size_of_parameters = mh->size_of_parameters();
callee_max_locals = mh->max_locals();
is_top_frame = false;
}
}
#endif /* !PRODUCT */
return bt;
JRT_END
class DeoptimizeMarkedClosure : public HandshakeClosure {
public:
DeoptimizeMarkedClosure() : HandshakeClosure("Deoptimize") {}
void do_thread(Thread* thread) {
JavaThread* jt = thread->as_Java_thread();
jt->deoptimize_marked_methods();
}
};
void Deoptimization::deoptimize_all_marked(nmethod* nmethod_only) {
ResourceMark rm;
DeoptimizationMarker dm;
// Make the dependent methods not entrant
if (nmethod_only != NULL) {
nmethod_only->mark_for_deoptimization();
nmethod_only->make_not_entrant();
} else {
MutexLocker mu(SafepointSynchronize::is_at_safepoint() ? NULL : CodeCache_lock, Mutex::_no_safepoint_check_flag);
CodeCache::make_marked_nmethods_not_entrant();
}
DeoptimizeMarkedClosure deopt;
if (SafepointSynchronize::is_at_safepoint()) {
Threads::java_threads_do(&deopt);
} else {
Handshake::execute(&deopt);
}
}
Deoptimization::DeoptAction Deoptimization::_unloaded_action
= Deoptimization::Action_reinterpret;
#if INCLUDE_JVMCI || INCLUDE_AOT
template<typename CacheType>
class BoxCacheBase : public CHeapObj<mtCompiler> {
protected:
static InstanceKlass* find_cache_klass(Symbol* klass_name, TRAPS) {
ResourceMark rm;
char* klass_name_str = klass_name->as_C_string();
Klass* k = SystemDictionary::find(klass_name, Handle(), Handle(), THREAD);
guarantee(k != NULL, "%s must be loaded", klass_name_str);
InstanceKlass* ik = InstanceKlass::cast(k);
guarantee(ik->is_initialized(), "%s must be initialized", klass_name_str);
CacheType::compute_offsets(ik);
return ik;
}
};
template<typename PrimitiveType, typename CacheType, typename BoxType> class BoxCache : public BoxCacheBase<CacheType> {
PrimitiveType _low;
PrimitiveType _high;
jobject _cache;
protected:
static BoxCache<PrimitiveType, CacheType, BoxType> *_singleton;
BoxCache(Thread* thread) {
InstanceKlass* ik = BoxCacheBase<CacheType>::find_cache_klass(CacheType::symbol(), thread);
objArrayOop cache = CacheType::cache(ik);
assert(cache->length() > 0, "Empty cache");
_low = BoxType::value(cache->obj_at(0));
_high = _low + cache->length() - 1;
_cache = JNIHandles::make_global(Handle(thread, cache));
}
~BoxCache() {
JNIHandles::destroy_global(_cache);
}
public:
static BoxCache<PrimitiveType, CacheType, BoxType>* singleton(Thread* thread) {
if (_singleton == NULL) {
BoxCache<PrimitiveType, CacheType, BoxType>* s = new BoxCache<PrimitiveType, CacheType, BoxType>(thread);
if (!Atomic::replace_if_null(&_singleton, s)) {
delete s;
}
}
return _singleton;
}
oop lookup(PrimitiveType value) {
if (_low <= value && value <= _high) {
int offset = value - _low;
return objArrayOop(JNIHandles::resolve_non_null(_cache))->obj_at(offset);
}
return NULL;
}
oop lookup_raw(intptr_t raw_value) {
// Have to cast to avoid little/big-endian problems.
if (sizeof(PrimitiveType) > sizeof(jint)) {
jlong value = (jlong)raw_value;
return lookup(value);
}
PrimitiveType value = (PrimitiveType)*((jint*)&raw_value);
return lookup(value);
}
};
typedef BoxCache<jint, java_lang_Integer_IntegerCache, java_lang_Integer> IntegerBoxCache;
typedef BoxCache<jlong, java_lang_Long_LongCache, java_lang_Long> LongBoxCache;
typedef BoxCache<jchar, java_lang_Character_CharacterCache, java_lang_Character> CharacterBoxCache;
typedef BoxCache<jshort, java_lang_Short_ShortCache, java_lang_Short> ShortBoxCache;
typedef BoxCache<jbyte, java_lang_Byte_ByteCache, java_lang_Byte> ByteBoxCache;
template<> BoxCache<jint, java_lang_Integer_IntegerCache, java_lang_Integer>* BoxCache<jint, java_lang_Integer_IntegerCache, java_lang_Integer>::_singleton = NULL;
template<> BoxCache<jlong, java_lang_Long_LongCache, java_lang_Long>* BoxCache<jlong, java_lang_Long_LongCache, java_lang_Long>::_singleton = NULL;
template<> BoxCache<jchar, java_lang_Character_CharacterCache, java_lang_Character>* BoxCache<jchar, java_lang_Character_CharacterCache, java_lang_Character>::_singleton = NULL;
template<> BoxCache<jshort, java_lang_Short_ShortCache, java_lang_Short>* BoxCache<jshort, java_lang_Short_ShortCache, java_lang_Short>::_singleton = NULL;
template<> BoxCache<jbyte, java_lang_Byte_ByteCache, java_lang_Byte>* BoxCache<jbyte, java_lang_Byte_ByteCache, java_lang_Byte>::_singleton = NULL;
class BooleanBoxCache : public BoxCacheBase<java_lang_Boolean> {
jobject _true_cache;
jobject _false_cache;
protected:
static BooleanBoxCache *_singleton;
BooleanBoxCache(Thread *thread) {
InstanceKlass* ik = find_cache_klass(java_lang_Boolean::symbol(), thread);
_true_cache = JNIHandles::make_global(Handle(thread, java_lang_Boolean::get_TRUE(ik)));
_false_cache = JNIHandles::make_global(Handle(thread, java_lang_Boolean::get_FALSE(ik)));
}
~BooleanBoxCache() {
JNIHandles::destroy_global(_true_cache);
JNIHandles::destroy_global(_false_cache);
}
public:
static BooleanBoxCache* singleton(Thread* thread) {
if (_singleton == NULL) {
BooleanBoxCache* s = new BooleanBoxCache(thread);
if (!Atomic::replace_if_null(&_singleton, s)) {
delete s;
}
}
return _singleton;
}
oop lookup_raw(intptr_t raw_value) {
// Have to cast to avoid little/big-endian problems.
jboolean value = (jboolean)*((jint*)&raw_value);
return lookup(value);